Sample records for photomagnetisme sous irradiation

  1. The Effect of Low Dose Irradiation and Grapefruit Extract on C. perfringens Growth from Spores in sous vide Processed Pork-Based Mexican Entrée

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Sous vide, a common cooking method for meat and poultry products is widely used for providing ready-to-eat meals. Traditionally, these products have limited shelf life, ranging from 2 to 3 weeks. However, similar products may be stored for longer periods in the U.S. and other countries, requiring ad...

  2. L'aventure sous-marine. Histoire de la plonge sous-marine de loisir en scaphandre autonome en France (1865-Vianney Mascret.

    E-print Network

    Paris-Sud XI, Université de

    L'aventure sous-marine. Histoire de la plongée sous-marine de loisir en scaphandre autonome en du 7 août 2006) Soutenue publiquement le 22 Octobre 2010 par M. MASCRET VIANNEY L'aventure sous-marine. Histoire de la plongée sous-marine de loisir en scaphandre autonome en France (1865-1985) Sous la direction

  3. Famille : Fabaceae Sous-famille : Mimosoideae

    E-print Network

    Paris-Sud XI, Université de

    Famille : Fabaceae Sous-famille : Mimosoideae Nom scientifique: Acacia mangium Willd. Synonymie : Racosperma mangium (Willd.) Pedley Nom commercial : brown salwood Acacia mangium est un grand arbre pouvant arille à la base. On compte environ 60.000 graines par kg. Acacia mangium L'arbre O.Monteuuis Acacia

  4. La veuve et son gendre dans la stratgie lectoraliste librale sous la Monarchie censitaire

    E-print Network

    Boyer, Edmond

    GAPP La veuve et son gendre dans la stratégie électoraliste libérale sous la Monarchie censitaire libérale sous la monarchie censitaire -- 2 -- halshs-00145863,version1-11May2007 #12;A. Verjus -- 3, spécialement sous la Monarchie de Juillet, 1900 ; S. Kent, Electoral procedure under Louis-Philippe, New

  5. M. Tillier, Prisons et autorits urbaines sous les Abbassides 1 PRISONS ET AUTORITS URBAINES SOUS LES ABBASSIDES

    E-print Network

    Paris-Sud XI, Université de

    M. Tillier, « Prisons et autorités urbaines sous les Abbassides » 1 PRISONS ET AUTORITÉS URBAINES'en offrent qu'une image éclatée et fragmentaire. Grâce à l'étude pionnière d'I. Schneider sur la prison dans'un juriste iraqien comme al-af (m. 261/874) laisse transparaître un schéma bipartite : certaines prisons

  6. TOURNOI DE GOLF Sous la prsidence d'honneur

    E-print Network

    Québec, Université du

    TOURNOI DE GOLF ANNUEL Sous la présidence d'honneur de Monsieur Henri-Paul Martel 13 septembre 2010 Club de golf La Prairie PR�SENT� PAR #12;MOT DU DIRECTEUR G�N�RAL Le tournoi de golf annuel du Fonds de, merci et bon golf! Yves Beauchamp, ing., Ph.D., MACG Directeur général #12;HORAIRE DE LA JOURN�E 9 h 30

  7. JournJournes techno mai 2008es techno mai 2008 11 tude des fluides soustude des fluides sous

    E-print Network

    Paris-Sud 11, Université de

    ), polycarbonate(AZ5GU ou 7075), polycarbonate UsinageUsinage SousSous--traitance (axes rectifitraitance (axes rectifiéés, cellules en polycarbonate)s, cellules en polycarbonate) PrPréé--assemblageassemblage Traitement

  8. Atomic displacements in low temperature irradiated chromium crystals M. Biget, F. Maury, P. Vajda, A. Lucasson (*) and P. Lucasson

    E-print Network

    Paris-Sud XI, Université de

    293 Atomic displacements in low temperature irradiated chromium crystals M. Biget, F. Maury, P interprétation des différentes sous-étapes jusqu'à 40 K. Abstract. 2014 Monocrystalline specimens of chromium potential particular to each metal. Very little is known about low temperature irradiated chromium. To our

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

    NASA Astrophysics Data System (ADS)

    Bouchard, Alexandre

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

  10. Fracture Mapping in the Soultz-sous-Forets Geothermal Field from Microearthquake Relocation

    E-print Network

    Michelet, Sophie

    2006-01-01

    In 2003, a massive hydraulic fracturing experiment was carried out at the European Geothermal Hot Dry Rock site at Soultz-sous-Forêts, France. The two week injection of water generated a high level of microseismic activity. ...

  11. Architecture pour la planification et l'exécution d'une Flotte de véhicules marins et sous-marins

    Microsoft Academic Search

    Assia Belbachir; Simon Lacroix

    2009-01-01

    Nous nous intéressons à l'architecture de robots marins et sous-marins autonomes dans le cadre de missions nécessitant leur coopération. Cette coopération s'avère difficile du fait que la commu- nication (acoustique) est de faible qualité et de faible portée. Afin d'illustrer notre travail, nous nous intéressons à un scénario de localisation d'une source d'eau chaude sous-marine. Pour cela, le véhicule sous

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

    PubMed Central

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

    2014-01-01

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

  13. Mail Irradiation

    MedlinePLUS

    Tobacco Smoke Mail Irradiation Food Irradiation Smoke Detectors Becoming Aware of Radiation Sources: Mail Irradiation In October, the deadly bacterium anthrax was found in mail sent to various news agencies, and to offices of the ...

  14. SOUS VIDE AND COOK-CHILL PROCESSING OF FOODS: CONCEPT DEVELOPMENT AND MICROBIOLOGICAL SAFETY

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Sous vide and cook-chill pasteurized, refrigerated ready-to-eat foods were introduced in about 1970 as a more convenient food option than frozen food for the food market, deli, foodservice kitchen, and home food preparer. Concerns have been expressed about the public-health risks associated with su...

  15. RLE DE LA PESTE PORCINE CLASSIQUE SOUS SA FORME SUB-CLINIQUE OU CHRONIQUE

    E-print Network

    Paris-Sud XI, Université de

    PATHOLOGIE PATHOLOGY RÔLE DE LA PESTE PORCINE CLASSIQUE SOUS SA FORME SUB-CLINIQUE OU CHRONIQUE de Pathologie porcine, I. N. R. A., 78850 Thiverval Grignon *Directeur du Laboratoire des Services'entre eux des foyers de peste porcine sub-clinique ou chronique à l'aide de l'isolement du virus mais

  16. Caractrisation des sous-dynamiques et applications (cole CIMPA Bobo-Dioulaso)

    E-print Network

    Sablik, Mathieu

    -shift de type fini (SFT ) il existe un ensemble fini de motifs F tel que T = T(A,d,F) M. Sablik (LATP]) . Remarque : Par définition, on a: ClFT(FS) = SFT M. Sablik (LATP) Caractérisation des sous { , }Z les blocs de ont une longueur paire} Ainsi SFT ClFact(SFT) M. Sablik (LATP) Caractérisation des

  17. Installation de VPN sous OS X "Jaguar"(10.2.x)

    E-print Network

    Skorobogatiy, Maksim

    Installation de VPN sous OS X "Jaguar"(10.2.x) Lancer d'abord l'application "Internect connect" (dans le répertoire "Applications" Dans le menu "Fichier" (ou "File"), choisir "Nouvelle connection VPN" Choisir "Continuer" Entrer l'adresse du serveur VPN, votre nom d'usager, et votre mot de passe d

  18. Comptes Rendus des JNC 17 -Poitiers 2011 Modlisation du comportement de composite matrice cramique sous

    E-print Network

    Boyer, Edmond

    céramique sous sollicitation de fatigue Modeling of ceramic matrix composite behavior under fatigue loading to determine the lifetime in fatigue of a ceramic matrix composite. This approach is done by coupling a very important role in the lifetime of the composite. Under oxidizing atmosphere, the ceramic matrix

  19. DISTILLATION DES LIQUIDES SOUS L'INFLUENCE DE L'LECTRICIT STATIQUE; PAR M. D. GERNEZ.

    E-print Network

    Paris-Sud XI, Université de

    36I DISTILLATION DES LIQUIDES SOUS L'INFLUENCE DE L'ÉLECTRICITÉ STATIQUE; PAR M. D. GERNEZ. La décharge, la distillation se produit aussitôt en sens in- verse (2). Ce phénomène est extrêmemen t n e sens suivant lequel se produit cette distillation est contraire à celui que sem- bleraient indiquer les

  20. La RSE dans les relations de sous-traitance : déterminants, diffusion et changements

    Microsoft Academic Search

    Dominique Casin

    2011-01-01

    La globalisation de l’économie a conduit les grandes entreprises ces vingt dernières années à recourir à des réseaux étendus de sous-traitants. Parallèlement, depuis les années 90 on assiste au développe-ment de la notion de responsabilité sociale des entreprises (RSE) en réaction aux pressions exercées par les différentes parties prenantes. Face à ces évolutions, le management des entreprises est devenu plus

  1. ETUDE DE LA STABILITE D'ECHANTILLONS D'EAU CONTAMINES EN PESTICIDES SOUS DIFFERENTES CONDITIONS

    E-print Network

    Boyer, Edmond

    1 ETUDE DE LA STABILITE D'ECHANTILLONS D'EAU CONTAMINES EN PESTICIDES SOUS DIFFERENTES CONDITIONS recherche, le prélèvement et la conservation des échantillons d'eaux en vue du dosage des pesticides à l contaminés par 22 pesticides. Différentes modalités de conservation ont été testées. Parallèlement, les

  2. THSE / UNIVERSIT DE RENNES 1 sous le sceau de l'Universit Europenne de Bretagne

    E-print Network

    Paris-Sud XI, Université de

    doctorale MATISSE présentée par Paul Bui Quang préparée à ONERA centre de Palaiseau INRIA Rennes Bretagne Professeur, Université de Rennes 1 / examinateur Nadia Oudjane Ingénieurchercheur, EDF R&D / examinateurANN�E 2013 TH�SE / UNIVERSIT� DE RENNES 1 sous le sceau de l'Université Européenne de Bretagne pour

  3. European HDR research programme at Soultz-sous-Forêts (France) 1987–1996

    Microsoft Academic Search

    Roy Baria; Jörg Baumgärtner; André Gérard; Reinhard Jung; John Garnish

    1999-01-01

    The site at Soultz-sous-Forêts (France) has been selected as the future European HDR research site (Garnish, J., Baria, R., Baumgärtner, J., Gérard, A., 1994. GRC Trans. 18, 431–438; Baria, R., 1990. Proceedings of Camborne School of Mines. International HDR Conference, June 1989, p. 613. Robertson Scientific Publications, London). Since 1987, extensive testing of the underground has been carried out using

  4. Instructions pour installer VPN sous OS-X (Panther) (10.3.1)

    E-print Network

    Skorobogatiy, Maksim

    Instructions pour installer VPN sous OS-X (Panther) (10.3.1) Installer d'abord votre configuration" (dans "Applications". Vérifier l'activité du port désiré. #12;Cliquer ensuite sur "VPN" Le système'installation est terminée. VPN peut être activé et désactivé grâce à l'icone ajouté au menu (voir ci-contre) En

  5. Informations pratiques : Dimanche 2 fvrier, rcitation de 14h 15h30, au sous-sol

    E-print Network

    Genève, Université de

    barre Alexandre le Grand, Jules César, Auguste, ou encore Trajan, sous les commentaires d'un Silène à l Chazaud, enseignant, titulaire d'un Master en histoire antique (Quirinus) M. Guy Le Comte, historien, professeur honoraire d'archéologie classique à l'Université de Genève (L'empereur Auguste) M. Marc Duret

  6. L'eau sous le Sahara : pas si fossile que a

    E-print Network

    N° 431 Mai 2013 L'eau sous le Sahara : pas si fossile que ça Scientific news Actualidad cientifica du Sahara septentrional étaient considérées comme « fossiles », c'est-à-dire non renouvelables, à l'en réalité, les nappes du système aquifère du Sahara septen- trional, de leur nom exact, sont aujourd

  7. Ocanographie / Oceanography Bathymay : la structure sous-marine de Mayotte rvle par l'imagerie multifaisceaux

    E-print Network

    Boyer, Edmond

    Océanographie / Oceanography 1/24 Bathymay : la structure sous-marine de Mayotte révélée par l 338 (2006) 1240-1249" DOI : 10.1016/j.crte.2006.07.010 #12;Océanographie / Oceanography 2/24 Résumé La hal-00870100,version1-28Oct2013 #12;Océanographie / Oceanography 3/24 Abridged English version

  8. Hématome sous capsulaire de foie compliquant une pré-éclampsie: à propos de 6 cas

    PubMed Central

    Mamouni, Nisrine; Derkaoui, Ali; Bougern, Hakima; Bouchikhi, Chehrazad; Chaara, Hikmat; Banani, Abdelaziz; Abdelilah, Melhouf Moulay

    2011-01-01

    L'hématome sous capsulaire du foie (HSCF) est une complication rare mais gravissime de la grossesse. Devant une symptomatologie clinique souvent non spécifique et un tableau biologique retardé, son diagnostic est basé essentiellement sur les moyens de l'imagerie (échographie, TDM, IRM). Son traitement est fonction de l'intégrité ou non de la capsule de Glisson. Nous rapportons les observations de 6 patientes, à travers une étude rétrospective s’étalant sur la période du Janvier 2005 à Octobre 2008, incluant tous les cas de preeclampsie colligés au service de gynécologie obstétrique du CHU Hassan II. Durant la période d’étude, L'incidence de l'hématome sous capsulaire de foie chez les patientes préeclamptiques admises durant la période d’étude est de 1,49 %. Aucune des patientes n'a benificié d'un suivi prénatal au sein de notre formation. La moyenne d’âge des patientes est de 37,6 ans avec des extrêmes allant de 33 à 45 ans. La gestité moyenne était de 4,8 avec une parité moyenne de 4,5.l'hematome sous capsulaire est survenu en post partum chez tous nos cas avec un délai moyen de 4 jours et des extrêmes allant de J0 et J10 du post partum .Toutes les patientes ont présenté un HELLP syndrome concomitant à la survenue de cette complication gravissime.Le diagnostic positif s'est basé sur les données échographiques dans 5 cas (hemoperitoine –HSCF).l’équipe a opté pour une abstention thérapeutique avec surveillance armée chez 2 cas et l'exploration chirurgicale a été indiquée chez quatre patientes en instabilité hemodynamique.Nous avons déploré deux cas de décès maternel. PMID:22145072

  9. Xavier Landrin, `Droite', `gauche', `juste-milieu' : la formalisation politique de l'entre-deux sous la Monarchie de Juillet , communication au colloque Gauche-droite : usages et enjeux d'un clivage

    E-print Network

    Paris-Sud XI, Université de

    'entre-deux sous la Monarchie de Juillet », communication au colloque « Gauche-droite : usages et enjeux d-milieu » : la formalisation politique de l'entre- deux sous la Monarchie de Juillet Xavier LANDRIN Université-milieu' : la formalisation politique de l'entre-deux sous la Monarchie de Juillet », communication au colloque

  10. Évaluation du grade des tumeurs endocrines du pancréas et ponction sous échoendoscopie

    Microsoft Academic Search

    G. Monges; F. Figuereido; M. Giovannini

    2010-01-01

    Résumé\\u000a Introduction  Les tumeurs endocrines du pancréas ont un profil évolutif variable. Le diagnostic de tumeur endocrine peut être obtenu par\\u000a ponction sous échoendoscopie (EUS-FNA). L’évaluation du pronostic à partir de ces échantillons est un vrai challenge, mais\\u000a paraît très important pour la prise en charge thérapeutique des patients. Le but de notre travail a été, sur une série rétrospective,\\u000a d’évaluer

  11. Irradiance Variability

    NASA Astrophysics Data System (ADS)

    Lean, J. L.

    2003-05-01

    From the solar interior emerges magnetic flux that alters the Sun's electromagnetic radiation, producing irradiance variability on a wide range of time scales. The organization, outward extension and expansion of magnetic fields structure the solar atmosphere and cause the entire electromagnetic spectrum to vary in different ways, depending on wavelength. Surface magnetic fields produce variations in near UV, visible and near IR spectra which emerge from the photosphere, and comprise the bulk of total irradiance. Yet the correlation of daily total irradiance and total magnetic field strength is poor; rather, the net effect of two different magnetic features - dark sunspots and bright faculae - better account for the variations observed in total irradiance during the solar cycle. The relationship of UV irradiance with magnetic flux is more direct since bright active regions control the global variations in both these quantities. Connecting X-ray and short wavelength EUV irradiance variations to the solar interior requires the extrapolation of emerging surface magnetic fields to the corona and assumptions about the relationship of their strengths and topologies with coronal pressure. Knowledge of the emergence, evolution, transport and decay of magnetic flux is thus a key to understanding and forecasting solar irradiance variability at all wavelengths. Identification of sizeable magnetic regions on the side of the Sun far from Earth may enable EUV and X-ray irradiance forecasts and subsequent space weather effects on time scales of days to weeks. On multi-decadal time scales improved knowledge of the sub surface dynamo and surface transport processes may help constrain secular solar irradiance evolution, needed for climate change attribution. Also needed is quantification of the association between the closed flux that controls irradiance variability and the open flux that extends into the heliosphere. Although utilized frequently to infer irradiance variability, proxies of long-term solar activity in tree-rings and ice-cores actually reflect heliospheric modulation of galactic cosmic rays. Funded by NASA and ONR.

  12. Analysis of macroscopic fractures in granite in the HDR geothermal well EPS1, Soultz-sous-Forêts, France

    Microsoft Academic Search

    Albert Genter; Hervé Traineau

    1996-01-01

    An exhaustive analysis of 3000 macroscopic fractures encountered in the geothermal Hot Dry Rock borehole, EPS-1, located inside the Rhine graben (Soultz-sous-Forêts, France), was done on a continuous core section over a depth interval from 1420 to 2230 m: 97% of the macroscopic structures were successfully reorientated with a good degree of confidence by comparison between core and acoustic borehole

  13. THESE H.D.R. / Universit de Bretagne-Sud sous le sceau de l'Universit europenne de Bretagne

    E-print Network

    Matheus, Frederic

    obtenir l' HABILITATION � DIRIGER DES RECHERCHES Mention : Mathématiques et interactions des mathématiques´ees sont enti`erement d´ecrites via le bord du groupe libre sous-jacent. La preuve repose sur l'existence d

  14. La rforme des prisons sous la troisime Rpublique Une co-gestion d'acteurs publics et privs.

    E-print Network

    Paris-Sud XI, Université de

    La réforme des prisons sous la troisième République Une co-gestion d'acteurs publics et privés. La France républicaine et les prisons1 Économiquement, socialement, culturellement, la IIIème république est prison est l'objet de nombreuses discussions entre les philanthropes et les hommes politiques. Les élites

  15. Comptes Rendus des JNC 16 Toulouse 2009 Essais et simulations des mes Nomex sous des sollicitations de type

    E-print Network

    Paris-Sud XI, Université de

    Comptes Rendus des JNC 16 Toulouse 2009 Essais et simulations des âmes Nomex sous des sollicitations de type statique et fatigue Experimental tests and prediction of Nomex cores under statique en cisaillement hors plan des âmes nids d'abeilles Nomex® lors de sollicitations de fatigue. La

  16. Sous la direction de Colette Dubois, professeur l'Universit d'Aix-Marseille I Membres du Jury

    E-print Network

    Boyer, Edmond

    Imbert-Vier le 24 novembre 2008 Frontières et limites à Djibouti durant la période coloniale (1884-1977) tel-00736163,version1-27Sep2012 #12;Frontières et limites à Djibouti durant la période coloniale (1884 revisitons l'histoire coloniale de Djibouti sous l'angle de la fabrication des territoires. Nous étudions

  17. Amorphization of ?-Quartz under Irradiation

    NASA Astrophysics Data System (ADS)

    Douillard, L.; Duraud, J. P.

    1996-12-01

    The course of radiation induced damage produced in ?-quartz by neutrons, ions, electrons or photons — commonly known as metamictization — has been re-analyzed by careful comparison of available experimental data. Specific interest was devoted to confront experimental metamict state features with current structural models. It comes out that the metamict state of irradiated quartz should exhibit some structural characteristics of the modulated structure proposed for vitreous silica. The metamictization process is consistent with a structural relaxation process of a highly defective quartz matrix. According to this new point defect analysis, structural relaxation should be triggered by a critical concentration of oxygen vacancy point defects likely to significantly lower the connectivity of the SiO{2} network. Various experimental results are interpreted by incorporating the influence of the SiO{2} crystalline polymorph and the influence of the nature of the irradiating particle to the point defect model. Nous avons étudié les modifications de propriétés et de structures de monocristaux de quartz ?, consécutives à une irradiation sévère par des neutrons, des ions, des électrons ou des photons. Ce phénomène d'altération du quartz sous irradiation porte le nom de métamictisation. Notre travail exploite les recoupements de travaux antérieurs. Une attention particulière a été portée à la confrontation entre les données structurales expérimentales disponibles sur l'état métamicte du quartz et les modèles structuraux proposés. L'état métamicte du quartz présente ainsi les caractéristiques structurales du modèle de structure modulée, avancé pour décrire la structure de la silice thermique. Le mécanisme de métamictisation procéderait par relaxation de la matrice cristalline fortement endommagée. Ce phénomène de relaxation serait initié par l'apparition de concentration critique de défauts ponctuels de type lacunes d'oxygène responsables d'une forte augmentation des degrés de liberté des tétraèdres élémentaires SiO{4} au sein du crystal. Ce modèle de défaut ponctuel permet, par la prise en compte de la nature de la forme cristalline du dioxyde de silicium et la nature du projectile utilisé, de rendre compte de l'essentiel des donnés expérimentales.

  18. Tonsil Irradiation

    Cancer.gov

    A cohort of about 3,000 individuals who were irradiated during childhood for benign head and neck conditions at Michael Reese Hospital was assembled and monitored for the risk of thyroid and other cancers.

  19. (A paratre dans: Saskta-sdhuta: Goodness of Sanskrit. Studies in honour of professor Ashok Aklujkar, sous la direction de Chikafumi Watanabe, Michele Desmairais, et Honda,

    E-print Network

    Paris-Sud XI, Université de

    Aklujkar, sous la direction de Chikafumi Watanabe, Michele Desmairais, et Honda, Yoshichika, New Delhi: DK Ashok Aklujkar, Chikafumi Watanabe, Michele Desmarais, Yoshichika Honda (Ed.) (2012) 311-329" #12;- 2

  20. Irradiance gradients

    SciTech Connect

    Ward, G.J. (Lawrence Berkeley Lab., CA (United States) Ecole Polytechnique Federale, Lausanne (Switzerland)); Heckbert, P.S. (Carnegie-Mellon Univ., Pittsburgh, PA (United States). School of Computer Science Technische Hogeschool Delft (Netherlands). Dept. of Technical Mathematics and Informatics)

    1992-04-01

    A new method for improving the accuracy of a diffuse interreflection calculation is introduced in a ray tracing context. The information from a hemispherical sampling of the luminous environment is interpreted in a new way to predict the change in irradiance as a function of position and surface orientation. The additional computation involved is modest and the benefit is substantial. An improved interpolation of irradiance resulting from the gradient calculation produces smoother, more accurate renderings. This result is achieved through better utilization of ray samples rather than additional samples or alternate sampling strategies. Thus, the technique is applicable to a variety of global illumination algorithms that use hemicubes or Monte Carlo sampling techniques.

  1. Irradiated foods

    MedlinePLUS

    ... and reduces the risk of food poisoning . Food irradiation is used in many countries. It was first approved in the U.S. to prevent sprouts on white potatoes and for the control of insects on wheat and in certain spices and seasonings.

  2. Evolution du taux de saponification d'acides gras d'huile de colza distribus sous forme de savons

    E-print Network

    Boyer, Edmond

    Evolution du taux de saponification d'acides gras d'huile de colza distribués sous forme de savons de dissociation - réassociation de savons d'AG d'huile de colza. L'expérimentation a été réalisée sur produit brut, 2 kg de foin, 1 kg d'aliment concentré du commerce et 600 g de savons calciques d'AG d'huile

  3. Etude de quelques métastannates de métaux bivalents et de leur évolution sous l'action de la chaleur

    Microsoft Academic Search

    Thérèse Dupuis

    1965-01-01

    Résumé L'étude de l'évolution des métastannates de Zn, Cd, Cu, Ni, Co, Mg et Ca sous l'action de la chaleur met en évidence des différences d'un stannate à l'autre. Les sels de cuivre et manganèse se dissocient totalement alors que ceux de cadmium, zinc, cobalt, magnésium et calcium se transforment en orthostannates qui sont identifiés par leur spectre d'absorption infrarouge.

  4. THORIE DU CLAQUAE DE L'ARGON SOUS L'EFFET DU RAYONNEMENT D'UN LASER

    E-print Network

    Paris-Sud XI, Université de

    401. TH�ORIE DU CLAQUA�E DE L'ARGON SOUS L'EFFET DU RAYONNEMENT D'UN LASER Par F. CERNUSCHI, A de l'argon à une pression Pa. Diverses théories essayent d'expliquer le phénomène de rupture, en se théorique des résultats obtenus par Minck [1] pour l'argon, qui donnent les puissances de seuil ou limite du

  5. MESURE DE LA TEMPRATURE DES PARTICULES LOURDES DANS UN JET DE PLASMA D'ARGON SOUS PRESSION (*)

    E-print Network

    Boyer, Edmond

    1187 MESURE DE LA TEMP�RATURE DES PARTICULES LOURDES DANS UN JET DE PLASMA D'ARGON SOUS PRESSION mesurer la tem- pérature atomique T0 d'un plasma d'argon faiblement ionisé (degré d'ionisation ~ 10-4, Ne ionized argon plasma (ionisation degree ~ 10-4, Ne ~ 1014 cm-3, Te ~ 6 000 K) for pressures ranging from 1

  6. Cours de C++ 2008/2009 ELI 5 -Polytech'UPMC La classe TABLE et ses sous-classes

    E-print Network

    Braunstein, Cécile - Fachbereich 3

    Cours de C++ 2008/2009 ELI 5 - Polytech'UPMC TD/TP 5 La classe TABLE et ses sous-classes Récupérer les chiers de la classe table fournis pour ce TP. /home/shared/ELI5_C++/tp5/exo1 Commencer par votre fonction dans le main 1 #12;Cours de C++ 2008/2009 ELI 5 - Polytech'UPMC Exercice 2 Dénition de la

  7. L'agriculture familiale mise sous normes : jusqu'o les producteurs d'ananas du Costa Rica

    E-print Network

    Paris-Sud XI, Université de

    L'agriculture familiale mise sous normes : jusqu'où les producteurs d'ananas du Costa Rica pourront-ils relever le défi ? Family Agriculture under Norms System : Can the pineapple Farmers in Costa Rica Face négatifs sur l'environnement. La production d'ananas dans le Nord du Costa Rica est plus particulièrement

  8. La chirurgie coronaire sous circulation extra-corporelle chez le patient diabétique

    PubMed Central

    Moutakiallah, Younes; Benzaghmout, Khadija; Aithoussa, Mahdi; Atmani, Nourreddine; Amahzoune, Brahim; Hatim, Abdedaim; Drissi, Mohamed; Benyass, Aatif; ElBekkali, Youssef; Boulahya, Abdelatif

    2014-01-01

    Nous rapportons les résultats de la chirurgie coronaire chez une population de coronariens diabétiques opérés sous circulation extra-corporelle dans le service de chirurgie cardiaque de l'hôpital militaire d'instruction Mohammed V de Rabat. C'est une étude rétrospective menée entre Janvier 2008 et Février 2012 (4 ans), portant sur 103 patients diabétiques consécutifs opérés pour pontage coronaire. L’âge moyen des patients était de 61±8,7ans (37-82ans) avec un sexe ratio (H/F) de 3,9. Tous les patients diabétiques de type 2 et sous traitement anti-diabétique ont été inclus dans cette étude. La sténose du tronc commun gauche était présente chez 26,2% des patients et 53,4% étaient tritronculaires. Quatre-vingt patients (78,6%) étaient insulino-nécessitant, l'Euro-score moyen était de 1,63±1% et le nombre moyen de pontage de 2,3±0,7. Les durées moyennes de la circulation extra-corporelle et du clampage aortique étaient respectivement de 134,4 ± 42 min et 76 ± 28 min. La mortalité hospitalière était de 2 décès (1,9%), les durées moyennes de ventilation artificielle, du séjour en réanimation et du séjour postopératoire étaient respectivement de 7h (5-16h), 48h (42-52h) et 15,6 ± 8,6 jours. Les complications postopératoires étaient l'infarctus du myocarde, l'infection de paroi, la médiastinite et le bas débit cardiaque chez respectivement 1,9%, 10,7%, 3,9% et 1,9% des patients. Il ressort de notre étude, que les facteurs prédictifs d'infection post opératoire étaient la durée de ventilation artificielle (p = 0,002), la durée de la circulation extra-corporelle (p < 0,001) en plus du tabac (p = 0,004) et de l'obésité (p = 0,005). Les patients ont été contactés par téléphone ou lors de la consultation régulière de contrôle. Le taux de suivi a atteint 92,1% et la survie à 2 ans était de 98,9% des patients contrôlés avec une mortalité tardive de 1% avec un décès suite à un accident vasculaire cérébral étendu. Le contrôle a montré un cas de ré-hospitalisation pour poussée d'insuffisance cardiaque mais aucun cas de récidive angineuse, d'infarctus du myocarde ou de besoin de revascularisation. La chirurgie coronaire chez le diabétique offre d'excellents résultats à court et à moyen terme au détriment d'une faible morbi-mortalité ce qui en fait le traitement de choix. PMID:25396025

  9. Lipid oxidation stability of omega-3- and conjugated linoleic acid-enriched sous vide chicken meat.

    PubMed

    Narciso-Gaytán, C; Shin, D; Sams, A R; Keeton, J T; Miller, R K; Smith, S B; Sánchez-Plata, M X

    2011-02-01

    Lipid oxidation is known to occur rather rapidly in cooked chicken meat containing relatively high amounts of polyunsaturated fatty acids. To assess the lipid oxidation stability of sous vide chicken meat enriched with n-3 and conjugated linoleic acid (CLA) fatty acids, 624 Cobb × Ross broilers were raised during a 6-wk feeding period. The birds were fed diets containing CLA (50% cis-9, trans-11 and 50% trans-10, cis-12 isomers), flaxseed oil (FSO), or menhaden fish oil (MFO), each supplemented with 42 or 200 mg/kg of vitamin E (dl-?-tocopheryl acetate). Breast or thigh meat was vacuum-packed, cooked (74°C), cooled in ice water, and stored at 4.4°C for 0, 5, 10, 15, and 30 d. The lipid oxidation development of the meat was estimated by quantification of malonaldehyde (MDA) values, using the 2-thiobarbituric acid reactive substances analysis. Fatty acid, nonheme iron, moisture, and fat analyses were performed as well. Results showed that dietary CLA induced deposition of cis-9, trans-11 and trans-10, cis-12 CLA isomers, increased the proportion of saturated fatty acids, and decreased the proportions of monounsaturated and polyunsaturated fatty acids. Flaxseed oil induced higher deposition of C18:1, C18:2, C18:3, and C20:4 fatty acids, whereas MFO induced higher deposition of n-3 fatty acids, eicosapentaenoic acid (C20:5), and docosahexaenoic acid (C22:6; P < 0.05). Meat lipid oxidation stability was affected by the interaction of either dietary oil or vitamin E with storage day. Lower (P < 0.05) MDA values were found in the CLA treatment than in the MFO and FSO treatments. Lower (P < 0.05) MDA values were detected in meat samples from the 200 mg/kg of vitamin E than in meat samples from the 42 mg/kg of vitamin E. Nonheme iron values did not affect (P > 0.05) lipid oxidation development. In conclusion, dietary CLA, FSO, and MFO influenced the fatty acid composition of chicken muscle and the lipid oxidation stability of meat over the storage time. Supranutritional supplementation of vitamin E enhanced the lipid oxidation stability of sous vide chicken meat. PMID:21248346

  10. Irradiation Information

    NSDL National Science Digital Library

    The Food Safety Consortium (FSC) is a federally created consortium consisting of researchers from the University of Arkansas, Iowa State University and Kansas State University. The FSC conducts research in poultry, beef, and pork production. This site contains summary articles from the FDA, the Washington Times, the Los Angeles Times, the Chicago Tribune, and newsletter articles from the FSC. Previously approved for use on poultry and fruits and vegetables in the US, irradiation can kill disease-causing bacteria like Salmonella and Escherichia coli 0157:H7 (discussed in the Scout Report for Science and Engineering's In the News section, September 17, 1997), and molds and funguses that cause rot. With recent US Food and Drug Administration (FDA) approval, irradiation can now be used to process red meat (e.g., beef, pork, lamb, and byproducts). The process involves exposing food to a source of radiation such as gamma rays from radioactive cobalt 60, cesium 137, or x-rays. No radioactive material is added to the product, and the technique is routinely used on grains and spices, as well as for sterilizing disposable medical devices. In spite of a number of tests conducted over the last 30 years substantiating its safety, irradiation has not gained widespread public acceptance in the US. This is largely due to the public's general fear of processes utilizing radiation. Supporters of the technology claim that it will virtually eliminate food-borne illness in the US, while skeptics feel that technology such as steam treatment can accomplish adequate sterilization without the purported risks and public concern associated with irradiation.

  11. Évolution de leucémies myéloïdes chroniques sous nilotinib après échec a l'imatinib

    PubMed Central

    Sawadogo, Salifo; Hien, Francis Michel; Ouédraogo, Macaire Sampawendé; Drabo, Youssouf Joseph

    2014-01-01

    C'est une étude observationnelle prospective ouverte: quatre leucémies myéloïdes chroniques résistant ou intolérant à l'Imatinib ont été traitées par le Nilotinib. Elles ont été incluses dans le programme GIPAP et suivies selon les recommandations de “European LeukemiaNet”. Trois ont un score de Sokal de haut risque et une de bas risque. Deux étaient hypertendues. Mises sous Nilotinib, il y a eu deux rémissions cytogénétiques complètes et deux échecs. Le traitement a été interrompu chez les deux rémissions complètes, l'un pour effet secondaire du Nilotinib et l'autre pour changement de pays. Les deux échecs sont dus à des résistances. Le Nilotinib réduisant la fréquence des mutations des leucémies myéloïdes chroniques à haut risque et risque intermédiaire, il serait judicieux d'utiliser ce produit en première intention dans ces cas - ci pour réduire la charge des examens complémentaires. Les pays à bas revenu confrontés à des problèmes de survie ont besoin de la solidarité mondiale pour prendre en charge les leucémies myéloïdes chroniques. PMID:25419280

  12. Injection coaxiale de poudres sous faisceau laser pour la réalisation de revêtements : problèmes physiques associés

    NASA Astrophysics Data System (ADS)

    Pelletier, J. M.; Sallamand, P.

    1995-03-01

    Laser leading is an attractive technique for surface treatment ; by injecting an appropriated powder into the laser beam, various coatings can be achieved : metallic, ceramic or metal matrix composites (MMC), on many substrates. In the present work, a physical analysis of the different phenomena occurring during the powder-laser interaction is reported, especially the energy absorption and the resulting temperature evolution. An experimental agreement is observed with experimental results obtained in MMC coatings, manufactured by using a coaxial nozzle. La technique d'injection de poudre sous un faisceau laser est une technique de traitement de surface qui permet la réalisation de revêtements métalliques, céramiques, composites à matrice métallique (CMM), ..., sur les matériaux les plus divers. Dans cette étude, nous analysons les phénomènes physiques intervenant lors de l'interaction laser-poudre et conduisant à l'absorption de l'énergie et donc à une évolution thermique. Pour valider notre modélisation simplifiée, différents revêtements, notamment CMM, sont réalisés à l'aide d'une buse coaxiale : l'accord est satisfaisant.

  13. Geodetic monitoring strategy at the geothermal sites of Soultz-sous-Forêts and Rittershoffen (Upper Rhine Graben, France)

    NASA Astrophysics Data System (ADS)

    Heimlich, Christine; Masson, Frédéric; Gourmelen, Noël

    2014-05-01

    The European Cenozoic rift system, and in particular the Upper Rhine Graben offers a high potential of deep geothermal energy due to the well known geothermal anomaly and to the number of subsurface temperature data from oil exploration in the Upper Rhine Graben. One example is the Soultz-sous-Forêts Enhance Geothermal System (EGS) located in the French part of the Upper Rhine Graben. The Soultz-sous-Forêts EGS started in 1987 as a deep geothermal research site. The wells are drilled in naturally fractured and altered granites from 3200 to 5260 m depth located in the vicinity of quasi North-South faults. It is the first EGS site connected to the electric network, its electric production capacity is of 1.5MWe. A second EGS site, ECOGI, is in development near the village of Rittershoffen located at 7 km from Soultz-sous-Forêts. The objective of ECOGI is to produce 24MWth energy for an industrial use with a doublet configuration of wells at depths around 2500 and 3000 meters. Both EGS sites benefit of the natural circulation of geothermal water. Some challenges in geothermal power plant are to understand the long-term behavior of the geothermal system and the induced seismicity. In the Soultz-sous-Forêts plant, borehole measures give evidences of aseismic slip (Bailleux et al., 2013). And previous geodetic monitoring studies of other deep geothermal plants show subsidence and horizontal displacements due to geothermal exploitation (e.g. Massonnet et al., 1997; Nishijima et al., 2005; Fialko and Simons, 2000). The ability of geodesy tools to provide information about dynamic behaviour and the change in the local stress field around the geothermal site make them a suitable method to meet these challenges. Therefore, we establish a long-term geodetic monitoring system of the two geothermal sites. This work presents the monitoring strategy and the preliminary results. We install a network of continuous GNSS and INSAR data are in acquisition. Our aim is to monitor local surface displacement in natural, in stimulation and production states of the geothermal plants. GNSS and INSAR are two spatial geodetic methods with millimeter accuracy. The GNSS provides information about the absolute 3D displacement at some point location. And the INSAR method gives high spatial (meters) information of relative displacement.

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

    PubMed

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

    2010-07-14

    The effect of blanching (95 +/- 3 degrees C) followed by sous vide (SV) processing (90 degrees C for 10 min) on levels of two polyacetylenes in parsnip disks immediately after processing and during chill storage was studied and compared with the effect of water immersion (WI) processing (70 degrees C for 2 min.). Blanching had the greatest influence on the retention of polyacetylenes in sous vide processed parsnip disks resulting in significant decreases of 24.5 and 24% of falcarinol (1) and falcarindiol (2) respectively (p < 0.05). Subsequent SV processing did not result in additional significant losses in polyacetylenes compared to blanched samples. Subsequent anaerobic storage of SV processed samples resulted in a significant decrease in 1 levels (p < 0.05) although no change in 2 levels was observed (p > 0.05). 1 levels in WI processed samples were significantly higher than in SV samples (p

  15. Monarchie et patriciats municipaux en Castille sous Charles II Le prsent travail traite des rapports de la monarchie et des patriciats

    E-print Network

    Paris-Sud XI, Université de

    1 Monarchie et patriciats municipaux en Castille sous Charles II Le présent travail traite des rapports de la monarchie et des patriciats municipaux en Castille à propos d'une affaire précise: le par elles au roi1 . Cet état de fait oblige la monarchie à demander la "prorrogation", indispensable à

  16. -Interprtation / organisation des donnes provenant d'appareils de mesure et de contrle fonctionnant sous des protocoles de communication diffrents (Bluetooth, Zigbee, WiFi, KNX...)

    E-print Network

    Boyer, Edmond

    fonctionnant sous des protocoles de communication différents (Bluetooth, Zigbee, WiFi, KNX...) - Unification fil IEE802.15.4/Zigbee et de noeuds mobiles (robots) Réseaux hétérogènes avec des capteurs'eau - Zigbee : présence sur les chaises, lit, température, lumière, mouvement - WiFi : caméras, robots

  17. tude des conditions de dmarrage d'un propulseur sous-marin vis d'Archimde en appui sur une argile

    E-print Network

    Boyer, Edmond

    'Archimède entraînée par un moteur à courant continu et prévue pour la portance et la propulsion d'un vecteur sous water content. An equation is given to describe the behaviour of the screw, using the coefficient,11]. Certains de ces travaux sont effectués à vitesses lentes et nécessitent une grande force de propulsion

  18. Le syndrome de Down, plus communment connu sous l'appellation de trisomie 21 s'accompagne trs souvent de pathologies que l'on

    E-print Network

    Rochaix, Jean-David

    Le syndrome de Down, plus communément connu sous l'appellation de «trisomie 21» s'accompagne très les personnes atteintes d'un syndrome de Down. L'étude ciblée et spécifique du chromosome 21 a révélé toute la population. La cardiopathie est un trouble fréquent du syndrome de Down. Si la présence d

  19. Congrs SHF : Energies Marines Renouvelables -EMR 2013, Brest, 9-10 octobre 2013 Olaya et al. Modle temporel pour houlognrateur MODLE TEMPOREL SOUS FORME DE REPRSENTATION

    E-print Network

    Brest, Université de

    is extracted from the incoming wave by a gearbox and a permanent magnet synchronous generator. According to [Yu permettant ainsi d'entraîner une génératrice synchrone à aimants permanents. Sous l'hypothèse de la théorie and the excitation forces due to heave motion in finite depth water. Given a frequency response for both radiation

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

    NASA Astrophysics Data System (ADS)

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

    1999-09-01

    In Part I we present a multidisciplinary analysis model for the prediction of functional connections between the design variables and the electromagnetical, electrical and thermal performances of a brushless permanent magnet motor. In this paper we have elaborated a design methodology for electrical motors supplied from a variable-frequency low-voltage source. The objective is to take into account the influence of the inverter's dynamics from the beginning of the design, for the same reasons as we do for electromechanical and thermal constraints. The procedure is based on a Sequential Quadratic Programming optimization method. Two techniques are used to take into account the influence of the inverter: the first one develops the performance analysis with the multidisciplinary model; the second one considers the inverter's current reference as a supplementary optimization variable for the control of the design. Optimization difficulties linked to the chopping of the converter are discuted in connection with a sensitivity analysis of the torque, with respect to the inverter's current reference; a method is proposed to enhance the performances of the algorithm. The method has been applied to the design of a permanent magnet brushless DC motor used in the propulsion system of an electrical scooter; evolution of the design with the complexity level of analysis model is evidenced. Dans une première partie nous avons développé un modèle d'analyse pluridisciplinaire qui établissait les dépendances fonctionnelles entre les variables de conception et les performances magnéto-électro-thermiques d'un moteur brushless à aimants permanents. Dans cet article nous décrivons une procédure de dimensionnement adaptée à la conception de la machine alimentée à fréquence variable sous faible tension. L'objectif est d'intégrer la dynamique du convertisseur électronique dès la phase initiale du dimensionnement, au même titre que les spécifications électromécaniques et thermiques. La procédure est gérée par une méthode d'optimisation déterministe de type Programmation Quadratique Séquentielle. Elle intègre l'influence du convertisseur au moyen de deux spécificités : la première consiste à évaluer les fonctions du problème d'optimisation sur la base du module d'analyse pluridisciplinaire ; la deuxième permet de contrôler l'évolution du dimensionnement au travers de variables d'optimisation dont la liste inclut les consignes de la commande en courant du convertisseur. Les difficultés d'optimisation liées au mode de fonctionnement discret du convertisseur sont discutées au regard du calcul de la sensibilité du couple électromagnétique envers la consigne de courant du convertisseur ; une méthode est proposée pour assurer la robustesse de la procédure en présence du convertisseur. L'application porte sur le dimensionnement d'un moteur à aimants permanents de type “brushless trapézoïdal" destiné à la traction d'un scooter électrique ; l'évolution de la structure optimale avec le degré de complexité du module d'analyse est mise en évidence.

  1. Dimensionnement des actionneurs électriques alimentés à fréquence variable sous faible tension: I. Analyse du problème couplé magnétique, thermique, électrique

    NASA Astrophysics Data System (ADS)

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

    1998-07-01

    In this paper, the autors present a model for the multidisciplinary operation analysis of a variable frequency electrical drive, in the case of low voltage supply. This model takes into account the coupling between the electromagnetic, thermal and electrical phenomena. It allows to evaluate the performances under permanent or transient thermal conditions, as we can find in the working cycles of electrical vehicles with on board energy supply. This model is a part of an optimal design procedure, which will be described in an other article. For this reason, this paper is devoted to explain the dependences between the design variables and the performances. The proposed model is applied to a permanent magnet brushless DC motor. The performances are evaluated for the S1 and S2 duty-cycling operations. The influence of the driving parameters of the converter is also examined. L'objectif de cet article est de présenter la synthèse d'un modèle d'analyse pluridisciplinaire adapté à la caractérisation des performances d'un entraînement électrique alimenté à fréquence variable sous faible tension. Le modèle prend en compte le couplage entre les phénomènes électromagnétique, thermique et électrique. Il permet d'étudier le fonctionnement sous les conditions de régime thermique permanent ou transitoire qui interviennent dans la définition des cycles de travail des engins de traction à énergie embarquée. Ce modèle d'analyse constitue un élément d'une procédure de dimensionnement optimal qui sera développée dans un article séparé; aussi l'exposé est-il conduit en explicitant les dépendances fonctionnelles entre les paramètres de dimensionnement et les performances. La procédure d'analyse est appliquée à l'étude d'un moteur à aimants permanents périphériques alimenté suivant le mode “brushless trapézoïdal"; les performances sont évaluées pour deux types de cycle de travail: le cycle S1 en régime permanent, et le cycle S2 en régime thermique transitoire; l'influence des paramètres de commande du convertisseur est examinée.

  2. Dcentralisation, systme Barbet et protection sociale des alins en Seine-Infrieure: dbats autour de la loi de 1838 sous la Monarchie de Juillet.

    E-print Network

    Boyer, Edmond

    autour de la loi de 1838 sous la Monarchie de Juillet. En 1830, les trois glorieuses portèrent à la tête de France à la fin de la Monarchie de Juillet. En 1844, Henry Barbet fut propulsé à la présidence du institutionnel et politique voir VIGIER (Ph.), La Monarchie de Juillet, Paris, 1965, 127p. ; BERTIER DE SAUVIGNY

  3. Classification de mines sous-marines partir de l'image sonar brute : caractrisation du contour de l'ombre porte par algorithme gntique

    E-print Network

    Paris-Sud XI, Université de

    1 Classification de mines sous-marines à partir de l'image sonar brute : caractérisation du contour de l'ombre portée par algorithme génétique Mine classification based on raw sonar data: shadow'approche classique est séquentielle : l'image sonar est tout d'abord segmentée afin d'obtenir une image binaire

  4. L'innovation dans les services publics Aprs une longue phase de mconnaissance et de sous-estimation, la question de l'innovation

    E-print Network

    Paris-Sud XI, Université de

    : organisation, process, produit, concept, innovation sociale, etc.). Il est également caractérisé par sonFaridah DJELLAL Faïz GALLOUJ L'innovation dans les services publics Après une longue phase de méconnaissance et de sous-estimation, la question de l'innovation dans les services est désormais prise au

  5. Source mechanisms of micro-earthquakes induced in hydraulic fracturing experiment at the HDR site Soultz-sous-Forêts (Alsace) in 2003 and their temporal and spatial variations

    Microsoft Academic Search

    J. Horálek; L. Dorbath; Z. Jechumtálová; J. Sílený

    2009-01-01

    We have investigated source mechanisms of microearthquakes induced in the 2003 hydrofracturing experiment in the GPK3 borehole of the Soultz-sous-Forêts Hot Dry Rock facility (located in the Rhine Graben) and their time and space distribution. During this massive hydrofatcturing a total of 34000m3 fluids with the wellhead pressure up to18 MPa were injected and about 5000 microearthquakes in the magnitude

  6. PROTONS, DEUTONS, TRITONS ET NOYAUX D'HLIUM MIS PAR 197Au SOUS L'ACTION DE PROTONS DE 154 MeV

    E-print Network

    Boyer, Edmond

    615. PROTONS, DEUTONS, TRITONS ET NOYAUX D'H�LIUM �MIS PAR 197Au SOUS L'ACTION DE PROTONS DE 154 Me spectres d'énergie des protons, deutons et tritons au-dessus de 30 MeV environ ont été mesurés à 15°, 30, deuterons and tritons above 30 MeV were measured at 15°, 30° and 60° and are compared with those obtained

  7. Safer Food with Irradiation

    E-print Network

    Thompson, Britta; Vestal, Andy; Van Laanen, Peggy

    2003-01-21

    material by C.M. Bruhn at the University of California-Davis Center for Consumer Marketing. is reduced when eggs are irradiated. These dif- ferences are so small that there is no effect on the American diet. What are the benefits of food irradiation... of Agriculture (USD A), and health organizations such as the W orld Health Organization, the American MedicalA ssociation, and the American Dietetic A ssociation ha v e endorsed the safety of irradi- ated food . Does irradiation cause cancer orother health...

  8. Ondes de surface transverses sous un réseau de bandes métalliques ou de sillons gravés sur substrats piézoélectriques

    NASA Astrophysics Data System (ADS)

    Gavignet, E.; Ballandras, S.; Bigler, E.

    1995-07-01

    This study is devoted to the theoretical calculation of the propagation characteristics of shear horizontal waves trapped in surface transverse wave (STW) resonators. The model implemented takes piezoelectricity into account and provides the principal parameters of the acoustic wave (propagation and attenuation coefficients, velocity, etc.) propagating under shallow groove or thin metal strip gratings. A numerical method has been used to resolve the equations of the problem. The results obtained are in good agreement with previous results without piezoelectricity. Calculation results are presented for delay lines designed with metal strip gratings deposited on AT-cut of quartz. On se propose dans cette étude de déterminer théoriquement les caractéristiques de propagation des ondes de cisaillement horizontal utilisées dans les résonateurs à ondes de surface transverses. Le modèle mis en œuvre prend en compte la piézoélectricité du substrat et permet de prédire les principales propriétés physiques de l'onde élastique (constante de propagation, atténuation, vitesse, etc.) sous une série périodique de bandes métalliques ou de sillons gravés. La méthode de résolution est numérique et basée sur une méthode dite de la sécante. Elle donne des résultats en accord avec ceux de la littérature obtenus grâce à des modèles sans piézoélectricité. Les calculs développés correspondent au cas de lignes à retard constituées d'un réseau de fines bandes métalliques déposées sur une coupe AT de quartz.

  9. Observations et Asteroseismologie de sous-naines de type B: Une nouvelle classe d'etoiles pulsantes

    NASA Astrophysics Data System (ADS)

    Billeres, Malvina

    Ce memoire recapitule les efforts d'exploration mis en place au cours des quatre dernieres annees dans la recherche de sous-naines de type B (sdB) pulsantes. Base sur des predictions theoriques definissant une bande d'instabilite centree autour de Teff ˜ 35000 K et log g ˜ 5.7, ce releve systematique dans l'hemisphere Nord avait pour objectifs: (1) de decouvrir des objets montrant des variations lumineuses, (2) de delimiter l'ampleur de ce phenomene dans le plan Teff - log g, (3) de determiner le degre de purete de la zone d'instabilite predite. Nous explicitons ici la strategie d'observation mise en place, la methode utilisee (photometrie rapide et presentons les resultats obtenus dont notamment la deconcerte de quatre sdB pulsantes oit EC 14026: PG 1047+003, KPD 2109+4401, KPD 1930+2752 et PG 0014+067. L'analyse des donnees recoltees nous permet tout d'abord de poser les bases d'une etude globale unique des caracteristiques de la classe des EC 14026 et, d'un autre cote, d'amorcer leur etude asteroseismologique.

  10. Geochemical modelling of fluid-rock interactions in the context of the Soultz-sous-Forêts geothermal system

    NASA Astrophysics Data System (ADS)

    Fritz, Bertrand; Jacquot, Emmanuel; Jacquemont, Benoit; Baldeyrou-Bailly, Armelle; Rosener, Michel; Vidal, Olivier

    2010-07-01

    The development of the Enhanced Geothermal System (EGS) at Soultz-sous-Forêts (France) has given to scientists an interesting opportunity for the application of geochemical modelling of water-rock interactions, combining theoretical studies with field and experimental data. The main results of four successive and complementary studies are summarized: geochemical modelling of fluid-rock interactions with prediction of dissolution/precipitation of minerals, feed-back effects on the mineralogy and petrography of the rock (major role of silicates in the geological past and of carbonates in the near future of the exploitation), experimental control of the dynamics of silicates under thermal gradient and relation between the evolution of the petrophysics of the rocks and the heat and mass transfers. The thermal cycle of the fluid, between 200 °C and 65 °C in the geothermal loop, may be responsible for dissolution/precipitation of minerals which modify the porosity and permeability of the granite, as it happened in the geological past, in relation with hydrothermal circulations in the Rhine Graben.

  11. Problems in food irradiation

    Microsoft Academic Search

    Gerner

    1972-01-01

    Within the framework of a report on a meeting of the study group Berlin ; of the GDCh task group on Food Chemistry and Forensic Chemistry'', a lecture ; given-by Guenter E. Mueller on Problems in Food Irradiation'' is reviewed. The ; lecture gives a brief survey of the development and present state of food ; irradiation, particularly discussing the

  12. Comminuting irradiated ferritic steel

    DOEpatents

    Bauer, Roger E. (Kennewick, WA); Straalsund, Jerry L. (Kennewick, WA); Chin, Bryan A. (Auburn, AL)

    1985-01-01

    Disclosed is a method of comminuting irradiated ferritic steel by placing the steel in a solution of a compound selected from the group consisting of sulfamic acid, bisulfate, and mixtures thereof. The ferritic steel is used as cladding on nuclear fuel rods or other irradiated components.

  13. Irradiator apparatus and method

    Microsoft Academic Search

    Woodbridge

    1984-01-01

    An irradiator of the type using a radioactive material as a source of radiation is combined with a gaseous liquid contact chamber. The irradiator has a casing having an input and output therefrom and a plurality of connected chambers formed in the casing and separated by walls having an opening therethrough. A plurality of gamma radiation sources are located in

  14. Irradiation Creep in Graphite

    SciTech Connect

    Ubic, Rick; Butt, Darryl; Windes, William

    2014-03-13

    An understanding of the underlying mechanisms of irradiation creep in graphite material is required to correctly interpret experimental data, explain micromechanical modeling results, and predict whole-core behavior. This project will focus on experimental microscopic data to demonstrate the mechanism of irradiation creep. High-resolution transmission electron microscopy should be able to image both the dislocations in graphite and the irradiation-induced interstitial clusters that pin those dislocations. The team will first prepare and characterize nanoscale samples of virgin nuclear graphite in a transmission electron microscope. Additional samples will be irradiated to varying degrees at the Advanced Test Reactor (ATR) facility and similarly characterized. Researchers will record microstructures and crystal defects and suggest a mechanism for irradiation creep based on the results. In addition, the purchase of a tensile holder for a transmission electron microscope will allow, for the first time, in situ observation of creep behavior on the microstructure and crystallographic defects.

  15. Irradiation-Induced Nanostructures

    SciTech Connect

    Birtcher, R.C.; Ewing, R.C.; Matzke, Hj.; Meldrum, A.; Newcomer, P.P.; Wang, L.M.; Wang, S.X.; Weber, W.J.

    1999-08-09

    This paper summarizes the results of the studies of the irradiation-induced formation of nanostructures, where the injected interstitials from the source of irradiation are not major components of the nanophase. This phenomena has been observed by in situ transmission electron microscopy (TEM) in a number of intermetallic compounds and ceramics during high-energy electron or ion irradiations when the ions completely penetrate through the specimen. Beginning with single crystals, electron or ion irradiation in a certain temperature range may result in nanostructures composed of amorphous domains and nanocrystals with either the original composition and crystal structure or new nanophases formed by decomposition of the target material. The phenomenon has also been observed in natural materials which have suffered irradiation from the decay of constituent radioactive elements and in nuclear reactor fuels which have been irradiated by fission neutrons and other fission products. The mechanisms involved in the process of this nanophase formation are discussed in terms of the evolution of displacement cascades, radiation-induced defect accumulation, radiation-induced segregation and phase decomposition, as well as the competition between irradiation-induced amorphization and recrystallization.

  16. Alaskan Commodities Irradiation Project

    SciTech Connect

    Zarling, J.P.; Swanson, R.B.; Logan, R.R.; Das, D.K.; Lewis, C.E.; Workman, W.G.; Tumeo, M.A.; Hok, C.I.; Birklid, C.A.; Bennett, F.L.

    1988-12-01

    The ninety-ninth US Congress commissioned a six-state food irradiation research and development program to evaluate the commercial potential of this technology. Hawaii, Washington, Iowa, Oklahoma and Florida as well as Alaska have participated in the national program; various food products including fishery products, red meats, tropical and citrus fruits and vegetables have been studied. The purpose of the Alaskan study was to review and evaluate those factors related to the technical and economic feasibility of an irradiator in Alaska. This options analysis study will serve as a basis for determining the state's further involvement in the development of food irradiation technology. 40 refs., 50 figs., 53 tabs.

  17. Why the seismicity induced in Soultz-sous-Forêts and Gross Schoenebeck enhanced geothermal fields are so different? (Invited)

    NASA Astrophysics Data System (ADS)

    Gaucher, E.; Kohl, T.

    2013-12-01

    In enhanced geothermal systems, hydraulic fracturing and hydraulic stimulation are techniques used to increase the reservoir permeability. Their secondary effect, the induced seismicity, is a unique means to image the fault network created or reactivated by the operations. The interpretation of the results for this latter application is however limited by the capabilities of the seismic network and by our understanding of the involved physical processes. Here, we propose to highlight systematic behaviors of the seismicity induced in enhanced geothermal reservoirs. This is performed through the analysis of two EGS sites which appear to behave very differently in terms of induced seismicity: the Soultz-sous-Forêts (France) and the Gross Schoenebeck (Germany) fields. Several physics-based models have been tested for these fields and these observations should be used to calibrate them and the underlying physical assumptions. The Soultz-sous-Forêts (France) geothermal field is located in the Upper Rhine valley. Over the development of this EGS, four wells have been drilled into the granitic basement, up to 5 km depth, and eight major stimulations were carried out to create the heat exchanger. Several major observations based on the large induced seismicity database have been made and can apply on other EGS. Hence, it was noticed that a) the induced seismicity mainly occurs along planar features, b) during stimulation, the induced seismicity becomes stronger over time and this is still observed after shut-in. Most often, the largest magnitude microearthquake occurs following shut-in, c) over a certain overpressure threshold, seismicity can be induced and also a clear Kaiser effect can be observed for already stimulated volumes, d) the stimulation and the circulation periods induce different seismic responses. At Gross Schoenebeck (Germany), the Dethlingen sandstones and the underlying andesitic volcanic rocks of the Rotliegend formation of the North German Basin constitute the target reservoirs. Six major stimulations of the well doublet carried out around or deeper than 4.2 km created hydrofractures. The three seismically monitored operations highlighted very weak seismic responses in terms of energy and quantity. Only 78 microearthquakes were identified during the major operation which involved ~13,000 m3 of injected water and which is a volume comparable to that injected at Soultz. Such seismogenic behavior is consistent with the creation of hydrofractures and with a mechanism of dilatant shear. Interestingly, the strongest microearthquakes (Mw ? -1) occurred on a pre-existing fault and similar observations were already made in hydrofractured oil and gas reservoir. Seemingly, the sudden increase of the seismic moment of the microearthquakes and the decrease of the b-value are indicators of the reactivation of pre-existing fractures from the newly created one. As underlined by these case studies where fluid stimulation was always involved, the observation of induced seismicity may drastically change; and we will try to identify the reasons of these differences and propose directions to get better understanding.

  18. Food irradiation in perspective

    NASA Astrophysics Data System (ADS)

    Henon, Y. M.

    1995-02-01

    Food irradiation already has a long history of hopes and disappointments. Nowhere in the world it plays the role that it should have, including in the much needed prevention of foodborne diseases. Irradiated food sold well wherever consumers were given a chance to buy them. Differences between national regulations do not allow the international trade of irradiated foods. While in many countries food irradiation is still illegal, in most others it is regulated as a food additive and based on the knowledge of the sixties. Until 1980, wholesomeness was the big issue. Then the "prerequisite" became detection methods. Large amounts of money have been spent to design and validate tests which, in fact, aim at enforcing unjustified restrictions on the use of the process. In spite of all the difficulties, it is believed that the efforts of various UN organizations and a growing legitimate demand for food safety should in the end lead to recognition and acceptance.

  19. Nasopharyngeal Radium Irradiation (NRI)

    MedlinePLUS

    ... received this treatment may experience delayed adverse health effects. In September 1995, we convened a workshop on "The Public Health Response to Nasopharyngeal Radium Irradiation." It brought together a diverse group of more ...

  20. Stability of ?-Irradiated Carmine

    NASA Astrophysics Data System (ADS)

    Cosentino, Hélio M.; Fontenele, Rinaldo S.; DelMastro, Nélida L.

    2005-01-01

    Carmine is a dye used mainly for coloring food products and galenicals but also in inks. As food irradiation is becoming a regular treatment for food preservation, it is desirable to have a proper knowledge about the radiation sensitivity of additives that can be included in the food formula. The aim of this work was to establish the radiation stability of carmine against Co-60 gamma radiation. Samples of 50% pure carmine powder as well as 50%, 10% and 5% aqueous solutions were irradiated in a Gammacell 220, dose rate of about 5.2 kGy/h, with doses of 0, 1, 2, 4, 8, 16 and 32 kGy. Spectrophotometric readings at 494 nm show a slight decrease of the absorbance as a function of dose: Samples irradiated with 4 and 32 kGy retained 95% and 90% of absorbance of the unirradiated samples respectively. These results indicate a rather good stability of carmine against ?-irradiation.

  1. Blood irradiation: Rationale and technique

    SciTech Connect

    Lewis, M.C. (Savannah Regional Center for Cancer Care, Memorial Medical Center, GA (USA))

    1990-01-01

    Upon request by the local American Red Cross, the Savannah Regional Center for Cancer Care irradiates whole blood or blood components to prevent post-transfusion graft-versus-host reaction in patients who have severely depressed immune systems. The rationale for blood irradiation, the total absorbed dose, the type of patients who require irradiated blood, and the regulations that apply to irradiated blood are presented. A method of irradiating blood using a linear accelerator is described.

  2. Andre MARQUET-HAVELANGE, L'eau au travers des cellules vgtales : un parcours sous haute surveillance ! Printemps des Sciences consacr au thme de l'Eau -Observatoire du Monde des Plantes -UniversitdeLige-21-29mars2001

    E-print Network

    Liège, Université de

    Andrée MARQUET-HAVELANGE, L'eau au travers des cellules végétales : un parcours sous haute -UniversitédeLiège-21-29mars2001 1/2 Module « Observatoire du Monde des Plantes » L'eau au travers des cellules végétales : un parcours sous haute surveillance ! Cellule végétale La cellule végétale est entourée d

  3. Profil de l'hémogramme chez les enfants paludéens de 0 à 5 ans sous quinine, cas de la République Démocratique du Congo

    PubMed Central

    Kabamba, Arsène Tshikongo; Lukumwena, Zet Kalala; Longanga, Albert Otshudi

    2014-01-01

    Le paludisme constitue un des problèmes de santé publique majeur en République Démocratique du Congo (RDC) à cause d'une part des risques d’épidémies dans certaines zones du pays et d'autre part à cause du nombre des malades et des décès qu'il provoque. Cette étude expose les aspects hématologiques liés à la prise de la quinine au cours du paludisme grave chez l'enfant. Pour ce faire, les prises de sang ont été effectuées à deux groupes d'enfants, dans différents centres hospitaliers de Lubumbashi: le premier groupe est constitué d'enfants gravement impaludés et sous traitement à la quinine; tandis que le second groupe, composé d'enfants impaludés aussi mais sans traitement à la quinine et sert de groupe témoin. Ces prélèvements ont été analysés pour une exploration de l'hémogramme par un dosage sérique des paramètres hématologiques ci-après: les globules rouges, l'hémoglobine, l'hématocrite et le volume globulaire moyen. Les résultats obtenus montrent une différence statistiquement significative entre les deux groupes d'enfants examinés. En effet, dans la majorité des cas, une augmentation des taux plasmatiques des paramètres hématologiques analysés a été observée dans le groupe d'enfants impaludés sous traitement à la quinine, traduisant ainsi l'apport de la quinine sur la stabilisation de l'hémogramme au cours d'un paludisme grave chez l'enfant de moins de cinq ans. PMID:25722768

  4. ORNL irradiation creep facility

    SciTech Connect

    Reiley, T.C.; Auble, R.L.; Beckers, R.M.; Bloom, E.E.; Duncan, M.G.; Saltmarsh, M.J.; Shannon, R.H.

    1980-09-01

    A machine was developed at ORNL to measure the rates of elongation observed under irradiation in stressed materials. The source of radiation is a beam of 60 MeV alpha particles from the Oak Ridge Isochronous Cyclotron (ORIC). This choice allows experiments to be performed which simulate the effects of fast neutrons. A brief review of irradiation creep and experimental constraints associated with each measurement technique is given. Factors are presented which lead to the experimental choices made for the Irradiation Creep Facility (ICF). The ICF consists of a helium-filled chamber which houses a high-precision mechanical testing device. The specimen to be tested must be thermally stabilized with respect to the temperature fluctuations imposed by the particle beam which passes through the specimen. Electrical resistance of the specimen is the temperature control parameter chosen. Very high precision in length measurement and temperature control are required to detect the small elongation rates relevant to irradiation creep in the test periods available (approx. 1 day). The apparatus components and features required for the above are presented in some detail, along with the experimental procedures. The damage processes associated with light ions are discussed and displacement rates are calculated. Recent irradiation creep results are given, demonstrating the suitability of the apparatus for high resolution experiments. Also discussed is the suitability of the ICF for making high precision thermal creep measurements.

  5. Interstitial irradiation for craniopharyngioma.

    PubMed

    Barlas, O; Bayindir, C; Can, M

    2000-01-01

    The results of interstitial irradiation treatment for craniopharyngioma in two patients with six year follow-ups are presented. Stereotactic interstitial irradiation with Iodine-125 sources as sole therapy was employed in two adult patients who refused surgical resection. The diagnoses were confirmed by stereotactic biopsy. The first tumour which underwent interstitial irradiation was solid and 4 cm in diameter, and the second, 2.7 cm in diameter, had both cystic and solid components. The implanted Iodine-125 seeds delivered 67 Gy and 60 Gy to tumour periphery at the rate of 12 and 14 cGy/h, respectively, were removed at the end of designated radiation periods. Tumour shrinkage and central hypodensity, first observed 3 months after irradiation, continued until one tumour shrank to less than 1 cm at 12 months, and the other disappeared completely at 24 months. In both cases functional integrity was restored, and neither radiation induced toxicity nor recurrence has occurred six years after treatment. The results in these two cases suggest that solid craniopharyngiomas are sensitive to interstitial irradiation. PMID:10883334

  6. [in Le Mythe :pratiques,rcits,thories,sous la dir. de M. Boccara, P. Catala et M. Zafiropoulos, Anthropos/Economica, Paris, 2004 (vol. II, pp. 255-274)

    E-print Network

    Paris-Sud XI, Université de

    [in Le Mythe :pratiques,récits,théories,sous la dir. de M. Boccara, P. Catala et M. Zafiropoulos dans un mythe lacandon (Chiapas, Mexique). PatrickPérez MAP, UMR 694 CNRS et MC Ecole Nationale2008 Manuscrit auteur, publié dans "Le mythe : pratiques, récits, théories - vol.2 (2004) 255-274" #12

  7. Neutron irradiation therapy machine

    Microsoft Academic Search

    Nunan

    1978-01-01

    In a neutron irradiation therapy machine for treating patients with a beam of high energy neutrons, a gantry is provided which supports a non-superconducting cyclotron proton accelerator and target for generating a neutron beam and which permits rotation of the accelerator and neutron beam around an axis of revolution coaxial with a patient treatment zone. A counter-weight is carried from

  8. Market trials of irradiated chicken

    NASA Astrophysics Data System (ADS)

    Fox, John A.; Olson, Dennis G.

    1998-06-01

    The potential market for irradiated chicken breasts was investigated using a mail survey and a retail trial. Results from the mail survey suggested a significantly higher level of acceptability of irradiated chicken than did the retail trial. A subsequent market experiment involving actual purchases showed levels of acceptability similar to that of the mail survey when similar information about food irradiation was provided.

  9. Low temperature irradiation tests on

    E-print Network

    McDonald, Kirk

    irradiated) Wire EDM Irradiation sample · 5N aluminum + Cu, Mg with 10 % cold work · RRR=450 ·1.35m@RT, 3 @10] #12;Irradiation sample Aluminum stabilizer sample from the superconductor by wire electrical wire resistance measurement by nano-voltmeter CERNOX CX-1050-SD close to sample temperature (also

  10. Irradiation Stability of Carbon Nanotubes

    E-print Network

    Aitkaliyeva, Assel

    2010-01-14

    was revealed by Raman spectroscopy study of irradiated carbon buckypapers. The deviations from linear relationship were observed for the samples irradiated to very high fluence values. Annealing of irradiated samples was able to reduce the value of ID/IG ratio...

  11. Etude du comportement et de la modélisation viscoplastique du zircaloy 4recristallisé sous chargements monotones et cycliques uni et multiaxes

    NASA Astrophysics Data System (ADS)

    Delobelle, P.; Robinet, P.

    1994-08-01

    The results of experiment performed on a recrystallized zircaloy 4 alloy in the intermediate temperature domain 20 leqslant T leqslant 400 ^{circ}C are presented. To characterize the anisotropy, especially at 350 ^{circ}C, the tests were made under both monotonic and cyclic uni- and bidirectional loadings, i.e. tension-compression, tension-torsion and tension-internal pressure tests. The different anisotropy coefficients and especially R^p = \\varepsilon^p_{??} /\\varepsilon^ p _ {{^-_-}{^-_-} } seem to be temperature independent. An important feature of the behavior of this alloy in the neighbourhood of 300 ^{circ}C is attributed to the dislocations-point defects interactions (dynamic strain aging), phenomena often observed in the solid solutions. For the 2D cyclic non proportional loadings it is shown that a weak supplementary hardening appears, which is a function of the degree of the phase lag. We propose to particularize and to apply a unified viscoplastic model with internal variables to the considered alloy, as the model as already been developed and identified elsewhere for other isotropic materials. From a general point of view the introduction of the anisotropy in the model is made by four tensors of rank 4 ; [ M] is assigned to the flow directions, [ N] to the linear parts of the kinematical hardening variables and [ Q] , [ R] respectively to the dynamic and static recoveries of these tensorial variables. This phenomenological formulation leads to a correct representation of the set of the experimental results presented at 350 ^{circ}C, which provides an a posteriori confirmation of the formalism used. On étudie, entre 20 et 400 ^{circ}C, à l'aide d'essais sous chargements multiaxiaux monotones et cycliques (traction, torsion et pression interne) les propriétés viscoplastiques anisotropes de tube de zircaloy 4 recristallisé. A la température de 350 ^{circ}C, l'anisotropie a été quantifiée de façon détaillée. Les quelques résultats obtenus à la température ambiante ainsi que l'indépendance du rapport R^p = \\varepsilon^p_{??}/\\varepsilon^ p_{{^-_-}{^-_-} } avec la température laissent supposer que l'ensemble des coefficients d'anisotropie ne dépendent pas de la température. Par contre, la fluidité de cet alliage présente un minimum très marqué au voisinage de 300 ^{circ}C. Ce comportement est imputable au vieillissement dynamique fréquemment observé dans les solutions solides d'insertion. Lors d'un chargement cyclique hors phase (traction-torsion déphasée à 90^{circ}) ce matériau présente un léger durcissement supplémentaire. On propose l'extension au cas du zircaloy 4 de la formulation d'un modèle viscoplastique unifié développé et identifié par ailleurs sur d'autres matériaux initialement isotropes. D'une manière générale, l'introduction de l'anisotropie dans ce modèle s'effectue par l'intermédiaire de quatre tenseurs d'ordre 4 affectant les directions d'écoulement [ M] , les parties linéaires des écrouissages cinématiques [ N] , ainsi que les restaurations dynamiques [ Q] et statiques [ R] de ces mêmes variables d'écrouissage. L'identification de ce modèle est discutée et réalisée à 350 ^{circ}C. On montre l'adéquation du formalisme à appréhender l'ensemble des caractéristiques mécaniques de cet alliage.

  12. Hydrothermal convection beneath an inclined basement-sediment interface : application to the Rhine graben and its Soultz-sous-Forêts temperature anomaly

    NASA Astrophysics Data System (ADS)

    Guillou-Frottier, L.; Carré, C.; Bourgine, B.; Bouchot, V.; Genter, A.

    2012-12-01

    Geothermal anomalies in sedimentary basins are strongly controlled by fluid circulation within permeable zones. Exploration of new targets requires the understanding of how and why hydrothermal circulation patterns establish in a particular zone. This study presents a new compilation of newly corrected bottom-hole temperature data in the French part of the Upper Rhine Graben, where the Soultz-sous-Forêts temperature anomaly is locked beneath a local horst structure. After a geostatistically constrained interpolation procedure, maps and cross-sections are extracted from the 3D thermal block, together with the associated standard deviations. Thermal anomalies are preferentially associated with the thickest zones of the permeable fractured Buntsandstein (sandstones) formation, in apparent contradiction with previous models where two major fault zones were suggested to control fluid flow. The underlying fractured granitic basement hosts fluid circulation patterns which are apparently controlled at large-scale by the inclined basement-sediments interface. Based on these observations, numerical models of hydrothermal convection including an inclined basement-sediments interface, a local horst structure, and realistic petrophysical properties have been carried out. The depth-decrease of permeability, the inclination of the interface and the fixed heat flow condition at the base of the model, explain why only a few upwellings can be triggered. Thermal anomalies and a measured temperature profile can be reproduced when fault permeability equals 10^-14 m^2. Interestingly, structure of convective patterns also exhibits a second hotter upwelling, 8 km east of the Soultz-sous-Forêts upwelling zone, where another geothermal exploration project is now underway. The understanding of hydrothermal convection with realistic fluid and rock properties clearly appears as a predictive tool for geothermal exploration strategies.

  13. FDA perspective on food irradiation

    SciTech Connect

    Pauli, G.H.

    1994-12-31

    The Center for Food Safety and Applied Nutrition (CFSAN) monitors the safety of food irradiation. A few limited uses are regulated, and occasionally CFSAN receives a petition for a new use. Despite extensive studies (more than 400) showing the safety of food irradiation, a cloud of suspicion continues to hang over this issue in the mind of the public. People perceive food irradiation and direct body irradiation as having similar implications. Food irradiation is banned in two states in the United States. Food is irradiated for the following purposes: delay of ripening, prevention of sprouting, eradication of pests and sterilization, and allowing commodities to be stored unrefrigerated for long periods of time. The dosage depends on the purpose of the irradiation. Radiolytic products are formed during irradiation and during storage afterward. Most of these products are also formed during conventional preservation. In 1980, CFSAN, then the Bureau of Foods, introduced the term unique radiolytic products for compounds not identified in foods after conventional processing. Although the existence of URPs was never proven chemically, the term has caused anxiety. Irradiation of foods in the commercially useful range does not generate radioactivity above natural background. Because radiolytic products formed from beef, chicken, and pork are primarily the same, irradiated foods of similar food groups may be evaluated generically.

  14. Food irradiation and the consumer

    NASA Astrophysics Data System (ADS)

    A Thomas, P.

    The poster presents a review of research work undertaken on the perception and understanding that consumers have of food irradiation. Food irradiation is not a revolutionary new food processing technique, in fact it is probably one of the most investigated methods presently available. Many countries such as Belgium, France, Denmark, Italy, Spain, the Netherlands and the United States of America permit food irradiation. In Britain it is presently banned although this is currently under review. Awareness of food irradiation by the general public in Britain, although not extensively researched would appear to be increasing, especially in the light of recent media coverage. New quantitative and qualitative work indicates that the general public are concerned about the safety and effectiveness of food irradiation. Research has shown that a large proportion of consumers in Britain, if given the opportunity to purchase irradiated food, would not do so. Further exploration into this response revealed the fact that consumers are confused over what food irradiation is. In addition, there is concern over the detection of irradiated food. The views presented in this paper, of the consumer reaction to irradiated food are of great importance to those involved in the food industry and industries allied to it, which are ultimately dependent on the consumer for their commercial survival.

  15. Food irradiation and sterilization

    NASA Astrophysics Data System (ADS)

    Josephson, Edward S.

    Radiation sterilization of food (radappertization) requires exposing food in sealed containers to ionizing radiation at absorbed doses high enough (25-70 kGy) to kill all organisms of food spoilage and public health significance. Radappertization is analogous to thermal canning is achieving shelf stability (long term storage without refrigeration). Except for dry products in which autolysis is negligible, the radappertization process also requires that the food be heated to an internal temperature of 70-80°C (bacon to 53°C) to inactivate autolytic enzymes which catalyze spoilage during storage without refrigeration. To minimize the occurence of irradiation induced off-flavors and odors, undesirable color changes, and textural and nutritional losses from exposure to the high doses required for radappertization, the foods are vacuum sealed and irradiated frozen (-40°C to -20°C). Radappertozed foods have the characteristic of fresh foods prepared for eating. Radappertization can substitute in whole or in part for some chemical food additives such as ethylene oxide and nitrites which are either toxic, carcinogenic, mutagenic, or teratogenic. After 27 years of testing for "wholesomeness" (safety for consumption) of radappertized foods, no confirmed evidence has been obtained of any adverse effecys of radappertization on the "wholesomeness" characteristics of these foods.

  16. Source mechanisms of micro-earthquakes induced in a fluid injection experiment at the HDR site Soultz-sous-Forêts (Alsace) in 2003 and their temporal and spatial variations

    Microsoft Academic Search

    Josef Horálek; Zuzana Jechumtálová; Louis Dorbath; Jan Sílený

    2010-01-01

    We have inverted the peak amplitudes of direct P waves of 45 micro-earthquakes with magnitudes between M = 1.4 and 2.9, which occurred during and after the 2003 massive fluid injection in the GPK3 borehole of the Soultz-sous-Forêts Hot Dry Rock facility. These events were recorded by a surface seismic network of 15 stations operated by the Ecole et Observatoire

  17. In : Un ethnologue entre Sahara, Kabylie et Ymen. Hommage Marceau Gast (sous la dir. de Salem CHAKER et Hlne CLAUDOT-HAWAD), Peeters, Louvain/Paris, 2013, 187-204

    E-print Network

    Paris-Sud XI, Université de

    1 In : Un ethnologue entre Sahara, Kabylie et Yémen. Hommage à Marceau Gast (sous la dir. de Salem, partager est, au Sahara, une véritable règle de vie. De ce comportement, Marceau a lui-même fait un art de travers Marceau, je découvrais deux univers : d'un côté, celui du Sahara, des Berbères, de l'Afrique de l

  18. George Sand et le thtre de Nohant : l'intimit de la cration dramatique Tout au long de sa vie, George Sand s'intresse au thtre sous toutes ses formes

    E-print Network

    Paris-Sud XI, Université de

    1 George Sand et le théâtre de Nohant : l'intimité de la création dramatique Tout au long de sa vie, George Sand s'intéresse au théâtre sous toutes ses formes et en particulier à ses formes marginales questions esthétiques, philosophiques et psychologiques que s'est posées George Sand pendant toute sa vie 2

  19. Correlation of irradiation data using activation fluences and irradiation temperature.

    NASA Technical Reports Server (NTRS)

    Lynch, J. H.

    1971-01-01

    Nil-ductility transition temperature data for A302-B ferritic steel were analyzed by using multiple regression. Four independent variables were used - i.e., specimen temperature during irradiation, and time-integrated specific activations (activation fluences) of fast-, intermediate-, and thermal-neutron detectors. The results of these analyses were predictive equations having the increase in transition temperature as the dependent variable. For a reference point, a similar analysis was also performed using the flux integral above 1 MeV and the irradiation temperature as independent variables. Also, the effect of excluding irradiation temperature from these analyses was studied. The results of the analyses showed that excellent correlation was achieved by using activation fluences and irradiation temperature as the independent variables. Irradiation temperature was found to account for from 29 to 46% of the data variability depending on the model used.

  20. Gamma irradiation of Sennae Folium

    Microsoft Academic Search

    H. Van Doorne; E. H. Bosch; J. H. Zwaving; E. T. Elema

    1988-01-01

    The effect of different doses of gamma irradiation on senna leaves was studied. No changes in sennoside content and composition were observed after irradiation with 25 kGy. It was demonstrated that a minimum dose of 10 kGy was necessary to obtain a product of good microbiological quality. Cold maceration of senna leaves has to be discouraged, because of unavoidable microbial

  1. Craniospinal Axis Irradiation in Children

    Microsoft Academic Search

    Dirk Rades; Ralf Holtzhauer; Rolf Baumann; Martin Leuwer; Johann Hinrich Karstens

    1999-01-01

    Purpose: For craniospinal axis irradiation in young children sometimes anesthesia is required. In order to minimize risks from the anesthesist's point of view supine position would be preferable to standard prone position. In case of irradiation in supine position verification of the 3-field junction in the cervical region causes problems, because there is no direct visual control. For such situations

  2. Food Irradiation for Produce Safety

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A research priority for the produce industry is the development of an effective, safe and commercially applicable kill step. Irradiation is a nonthermal process that has been shown to inactivate human pathogens from fruits and vegetables. Irradiation treatment at 1.0 kGy can reduce the surface popul...

  3. Investigation of fluid flow paths within granitic batholiths: the Soultz-sous-Forêts 'Enhanced Geothermal System' and the Catalan Coastal Ranges examples

    NASA Astrophysics Data System (ADS)

    Place, Joachim; Geraud, Yves; Diraison, Marc; Le Garzic, Edouard; Sausse, Judith

    2010-05-01

    Geothermal exploitation of deep and hot rocks at industrial scale requires an accurate assessment of the available resource. In particular, temperature, porosity, connected porosity, fluids path, permeability, rock volume attainable by drainage, have to be constrained to forecast the potential of an area, and to further manage the heat resource during exploitation. We will present our work devoted to structural controls on fluid circulations in deep granitic basements. The first example is the current Soultz-sous-Forêts EGS being developed for over 20 years in the hot granite of the Upper Rhine Graben. Depth levels of naturally flowing deformation zones are known at well positions, but the fluid flow paths between the boreholes are still poorly understood. Our new developments of Vertical Seismic Profiling methods provide mapping of these permeable structures between the boreholes in 3D, below the sedimentary filling of the graben in the 1500-3500 depth range. As typical hercynian strike directions are identified, this study demonstrates the major role of inherited structures in the control of fluid flow paths. 3D representation with gOcad allows to build a reservoir model from various data. Such 3D approach is of major importance to identify the structural relations between the faults populations, especially their intersections and connectivity. The second example is also located within the European Cenozoic Rift System. Outcropping granites of the Catalan Coastal Ranges allow to access their structures in 3D with a comprehensive set of methods. Multi-scalar fractures have been identified from Digital Elevation Model to field analysis. Carbonate fillings are observed in fractures of specific orientations. They illustrate old fluid flow paths occurring in natural conditions. Conditions of their emplacement are provided by geochemical signatures. The geometry of the veins (orientations and connections) and their distribution illustrate how a rock mass volume can be drained by fluids. In addition, intragranitic faults are investigated by seismic, electric, radar and petrophysical methods in order to characterize their control on fluid transfers. These two granitic massifs currently present similar thermal anomalies, seismic and geothermal (hot springs) activities, and evidences of hydrothermal alteration. As the Soultz-sous-Forêts granitic basement is covered by thick sediments (1500 m), the indirect characterization led on the analogue outcropping batholith provides information about scaling of faults and fractures, and network of fluid circulations. In the two examples the reactivation of inherited structures is obvious. Periods of fault initiation and further activations are key elements to investigate the granite history. A conceptual model for the drainage of a granitic mass is proposed from regional to fracture scales.

  4. Time-resolved seismic tomography at the EGS geothermal reservoir of Soultz-Sous-Forêts (France) during hydraulic stimulations. A comparison between different injection tests

    NASA Astrophysics Data System (ADS)

    Dorbath, C.; Calo, M.; Cornet, F.; Frogneux, M.

    2011-12-01

    One major goal of monitoring seismicity accompanying hydraulic fracturing of a reservoir is to recover the seismic velocity field in and around the geothermal site. Several studies have shown that the 4D (time dependent) seismic tomographies are very useful to illustrate and study the temporal variation of the seismic velocities conditioned by injected fluids. However, only an appropriate separation of the data in subsets and a reliable tomographic method allow studying representative variations of the seismic velocities during and after the injection periods. We present here new 4D seismic tomographies performed using datasets regarding some stimulation tests performed at the Enhanced Geothermal System (EGS) site of Soultz-sous-Forêts (Alsace, France). The data used were recorded during the stimulation tests occurred in 2000, 2003 and 2004 that involved the wells GPK2, GPK3 and GPK4. For each set of events, the subsetting of the data was performed by taking into account the injection parameters of the stimulation tests (namely the injected flow rate and the wellhead pressure). The velocity models have been obtained using the Double-Difference tomographic method (Zhang and Thurber 2003) and further improved with the post-processing WAM technique (Calo' et al., 2009, 2011). This technique resulted very powerful because combines high resolution and reliablity of the seismic velocity fields calculated even with small datasets. In this work we show the complete sequence of the time-lapse tomographies and their variations in time and between different stimulation tests.

  5. Effect of the addition of conventional additives and whey proteins concentrates on technological parameters, physicochemical properties, microstructure and sensory attributes of sous vide cooked beef muscles.

    PubMed

    Szerman, N; Gonzalez, C B; Sancho, A M; Grigioni, G; Carduza, F; Vaudagna, S R

    2012-03-01

    Beef muscles submitted to four enhancement treatments (1.88% whey protein concentrate (WPC)+1.25% sodium chloride (NaCl); 1.88% modified whey protein concentrate (MWPC)+1.25%NaCl; 0.25% sodium tripolyphosphate (STPP)+1.25%NaCl; 1.25%NaCl) and a control treatment (non-injected muscles) were sous vide cooked. Muscles with STPP+NaCl presented a significantly higher total yield (106.5%) in comparison to those with WPC/MWPC+NaCl (94.7% and 92.9%, respectively), NaCl alone (84.8%) or controls (72.1%). Muscles with STPP+NaCl presented significantly lower shear force values than control ones; also, WPC/MWPC+NaCl added muscles presented similar values than those from the other treatments. After cooking, muscles with STPP+NaCl or WPC/MWPC+NaCl depicted compacted and uniform microstructures. Muscles with STPP+NaCl showed a pink colour, meanwhile other treatment muscles presented colours between pinkish-grey and grey-brown. STPP+NaCl added samples presented the highest values of global tenderness and juiciness. The addition of STPP+NaCl had a better performance than WPC/MWPC+NaCl. However, the addition of WPC/MWPC+NaCl improved total yield in comparison to NaCl added or control ones. PMID:22112522

  6. Procedure to construct three-dimensional models of geothermal areas using seismic noise cross-correlations: application to the Soultz-sous-Forêts enhanced geothermal site

    NASA Astrophysics Data System (ADS)

    Calò, Marco; Kinnaert, Xavier; Dorbath, Catherine

    2013-09-01

    The aim of this work is to assess the feasibility of the noise-cross correlation tomography method for imaging and detecting potential geothermal reservoirs even in highly urbanised areas. We tested the noise correlation method to reconstruct the shape of the Soutlz-sous-Forêts enhanced geothermal system (northern Alsace, France). We inverted Rayleigh waves (RWs) reconstructed from cross-correlations of 15 months of ambient seismic noise recorded by a seismic array installed around the Soutlz geothermal power plant. By correlating noise records between 22 receivers, we reconstructed RWs with sufficient signal-to-noise ratio for 231 interstation paths. The reconstructed waveforms were used to estimate group velocity dispersion curves at periods between 1.0 and 5.0 s. The results were inverted for 2-D group velocity maps, and finally for a 3-D S-wave velocity model from 0 to 5.2 km depth. Our results clearly show the presence of low velocity bodies in the crystalline basement below the Soultz power plant at depth of 4-5 km, and at shallower depth (2.5-3.5 km) beneath the Rittershoffen and Woerth villages. These observations, in agreement with some previous studies, confirm that our procedure is suitable for geothermal exploration. Furthermore, the model presented here provides some suggestions to improve the existing geothermal power plant and inferences for further explorations in the area.

  7. Different behaviours of the seismic velocity field at Soultz-sous-Forêts revealed by 4-D seismic tomography: case study of GPK3 and GPK2 injection tests

    NASA Astrophysics Data System (ADS)

    Calò, Marco; Dorbath, Catherine

    2013-08-01

    The geothermal power plant of Soultz-sous-Forêts in Northeastern France consists of three boreholes (GPK2, GPK3, GPK4) reaching a depth of about 5 km. All the wells were stimulated through hydraulic injections. In this study, we present the results of a time-dependent (4-D) seismic tomography obtained with the P-wave arrival times of seismic events recorded in 2003 during the stimulation of the GPK3 well. The method combines double-difference tomography with the Weighted Average Model post-processing that corrects for parameter dependence effects. In light of additional processing of the continuous seismic records of 23 surface stations, some 4728 precisely located events were selected and separated into 13 subsets to examine periods defined with respect to the injection scheme. Particular attention is given to changes in injected flow rates, periods of stationary injection conditions, periods of dual stimulation with the GPK2 well and post-injection periods. Results confirm that significant structures crossing the well have controlled the evolution of the seismicity and have played a fundamental role in the distribution and amplitude of the seismic anomalies. Furthermore, the evolution of the seismic velocity field, together with the representation of the relocated seismicity, have been compared with the results of the 4-D tomography of the GPK2 well, which is located at only 600 m from the stimulated well.

  8. AFIP-4 Irradiation Summary Report

    SciTech Connect

    Danielle M Perez; Misti A Lillo; Gray S. Chang; Glenn A Roth; Nicolas Woolstenhulme; Daniel M Wachs

    2011-09-01

    The Advanced Test Reactor (ATR) Full size plate In center flux trap Position (AFIP) experiment AFIP-4 was designed to evaluate the performance of monolithic uranium-molybdenum (U-Mo) fuels at a scale prototypic of research reactor fuel plates. The AFIP-4 test further examine the fuel/clad interface and its behavior under extreme conditions. After irradiation, fission gas retention measurements will be performed during post irradiation (PIE). The following report summarizes the life of the AFIP-4 experiment through end of irradiation, including a brief description of the safety analysis, as-run neutronic analysis results, hydraulic testing results, and thermal analysis results.

  9. AFIP-4 Irradiation Summary Report

    SciTech Connect

    Danielle M Perez; Misti A Lillo; Gray S. Chang; Glenn A Roth; Nicolas Woolstenhulme; Daniel M Wachs

    2012-01-01

    The Advanced Test Reactor (ATR) Full size plate In center flux trap Position (AFIP) experiment AFIP-4 was designed to evaluate the performance of monolithic uranium-molybdenum (U-Mo) fuels at a scale prototypic of research reactor fuel plates. The AFIP-4 test further examine the fuel/clad interface and its behavior under extreme conditions. After irradiation, fission gas retention measurements will be performed during post irradiation (PIE)1,2. The following report summarizes the life of the AFIP-4 experiment through end of irradiation, including a brief description of the safety analysis, as-run neutronic analysis results, hydraulic testing results, and thermal analysis results.

  10. Calculating Irradiance For Photosynthesis In The Ocean

    NASA Technical Reports Server (NTRS)

    Collins, Donald J.; Davis, Curtiss O.; Booth, C. Rockwell; Kiefer, Dale A.; Stallings, Casson

    1990-01-01

    Mathematical model predicts available and usable irradiances. Yields estimates of irradiance available for photosynthesis (Epar) and irradiance usable for photosynthesis (Epur) as functions of depth in ocean. Describes Epur and Epar in terms of spectral parameters measured remotely (from satellites or airplanes). These irradiances useful in studies of photosynthetic productivity of phytoplankton in euphotic layer.

  11. Irradiation pretreatment for coal desulfurization

    NASA Technical Reports Server (NTRS)

    Hsu, G. C.

    1979-01-01

    Process using highly-penetrating nuclear radiation (Beta and Gamma radiation) from nuclear power plant radioactive waste to irradiate coal prior to conventional desulfurization procedures increases total extraction of sulfur.

  12. Lithium Irradiation Experiment

    SciTech Connect

    Leveling, A.F.; /Fermilab

    2000-08-22

    The subject of tritium production in the Antiproton Source Collection lens was raised in the mid-1980s during the design phase of the pbar source. Interest in it has recurred during development of the proton lens and in recent investigations to determine the feasibility of liquid lithium collection lenses for the pbar source and a muon collider project. Calculations for tritium and beryllium 7 production on lithium suffer from a lack of information on medium and high energy cross section data. In addition, knowledge of the energy spectrum within the target vault is based upon calculations. Knowledge of the low energy spectrum, important for tritium production on lithium, is limited, if not non-existent. For Collider Run II, effort is to be applied to improve the performance of the solid lithium lens. Historically, examination of failed lithium lenses has not been pursued because they have been fairly radioactive and because they are thought to contain significant quantities of the radionuclides tritium and beryllium 7. The development of methods to examine failed lithium lenses may be desirable so that the specific causes of failure can be discovered. From such studies, design improvements can be incorporated with the goal of achieving lens performances goals related to Collider Run II. The purpose of the lithium irradiation experiment is to determine the production rates of radioisotopes tritium and beryllium 7 within the lithium lens in its operating in its operating environment.

  13. (Irradiation creep of graphite)

    SciTech Connect

    Kennedy, C.R.

    1990-12-21

    The traveler attended the Conference, International Symposium on Carbon, to present an invited paper, Irradiation Creep of Graphite,'' and chair one of the technical sessions. There were many papers of particular interest to ORNL and HTGR technology presented by the Japanese since they do not have a particular technology embargo and are quite open in describing their work and results. In particular, a paper describing the failure of Minor's law to predict the fatigue life of graphite was presented. Although the conference had an international flavor, it was dominated by the Japanese. This was primarily a result of geography; however, the work presented by the Japanese illustrated an internal program that is very comprehensive. This conference, a result of this program, was better than all other carbon conferences attended by the traveler. This conference emphasizes the need for US participation in international conferences in order to stay abreast of the rapidly expanding HTGR and graphite technology throughout the world. The United States is no longer a leader in some emerging technologies. The traveler was surprised by the Japanese position in their HTGR development. Their reactor is licensed and the major problem in their graphite program is how to eliminate it with the least perturbation now that most of the work has been done.

  14. Slag recycling of irradiated vanadium

    SciTech Connect

    Gorman, P.K.

    1995-04-05

    An experimental inductoslag apparatus to recycle irradiated vanadium was fabricated and tested. An experimental electroslag apparatus was also used to test possible slags. The testing was carried out with slag materials that were fabricated along with impurity bearing vanadium samples. Results obtained include computer simulated thermochemical calculations and experimentally determined removal efficiencies of the transmutation impurities. Analyses of the samples before and after testing were carried out to determine if the slag did indeed remove the transmutation impurities from the irradiated vanadium.

  15. Neutron irradiation on carbon nanocapsules

    Microsoft Academic Search

    A. Kasuya; H. Takahashi; Y. Saito; T. Mitsugashira; T. Shibayama; Y. Shiokawa; I. Satoh; M. Fukushima; Y. Nishina

    1996-01-01

    Carbon nanocapsules containing nanometer-size particles of molybdenum carbide have been irradiated by neutrons of flux 1014 N cm?2 s?1 for 6 days. The ?-ray spectrometry shows 1010 Bq g?1 of Mo-99 which is transformed from Mo-89 and decays into Tc-99. Our investigation by transmission electron microscopy indicates that the nanocapsule is robust against our neutron irradiation and used as a

  16. Proton irradiation effect on SCDs

    E-print Network

    Yan-Ji Yang; Jing-Bin Lu; Yu-Sa Wang; Yong Chen; Yu-Peng Xu; Wei-Wei Cui; Wei Li; Zheng-Wei Li; Mao-Shun Li; Xiao-Yan Liu; Juan Wang; Da-Wei Han; Tian-Xiang Chen; Cheng-Kui Li; Jia Huo; Wei Hu; Yi Zhang; Bo Lu; Yue Zhu; Ke-Yan Ma; Di Wu; Yan Liu; Zi-Liang Zhang; Guo-He Yin; Yu Wang

    2014-04-19

    The Low Energy X-ray Telescope is a main payload on the Hard X-ray Modulation Telescope satellite. The swept charge device is selected for the Low Energy X-ray Telescope. As swept charge devices are sensitive to proton irradiation, irradiation test was carried out on the HI-13 accelerator at the China Institute of Atomic Energy. The beam energy was measured to be 10 MeV at the SCD. The proton fluence delivered to the SCD was $3\\times10^{8}\\mathrm{protons}/\\mathrm{cm}^{2}$ over two hours. It is concluded that the proton irradiation affects both the dark current and the charge transfer inefficiency of the SCD through comparing the performance both before and after the irradiation. The energy resolution of the proton-irradiated SCD is 212 eV@5.9 keV at $-60\\,^{\\circ}\\mathrm{C}$, while it before irradiated is 134 eV. Moreover, better performance can be reached by lowering the operating temperature of the SCD on orbit.

  17. Proton irradiation effect on SCDs

    NASA Astrophysics Data System (ADS)

    Yang, Yan-Ji; Lu, Jing-Bin; Wang, Yu-Sa; Chen, Yong; Xu, Yu-Peng; Cui, Wei-Wei; Li, Wei; Li, Zheng-Wei; Li, Mao-Shun; Liu, Xiao-Yan; Wang, Juan; Han, Da-Wei; Chen, Tian-Xiang; Li, Cheng-Kui; Huo, Jia; Hu, Wei; Zhang, Yi; Lu, Bo; Zhu, Yue; Ma, Ke-Yan; Wu, Di; Liu, Yan; Zhang, Zi-Liang; Yin, Guo-He; Wang, Yu

    2014-08-01

    The Low Energy X-ray Telescope is one of the main payloads on the Hard X-ray Modulation Telescope satellite. Swept charge devices (SCDs) are selected as detectors for the Low Energy X-ray Telescope. As SCDs are sensitive to proton irradiation, irradiation tests were carried out on the HI-13 accelerator at the China Institute of Atomic Energy. The beam energy was measured to be 10 MeV at the SCD. The proton fluence delivered to the SCD was 3×108protons/cm2 over two hours. By comparing the performance before and after irradiation, it is concluded that proton irradiation affects both the dark current and the charge transfer inefficiency of the SCD. The energy resolution of the proton-irradiated SCD is 212 eV@5.9 keV at -60°C, while it before irradiated is 134 eV. Moreover, better performance can be reached by lowering the operating temperature of the SCD in orbit.

  18. Seismic velocity variations at the EGS geothermal reservoir of Soultz-Sous-Forêts (France): Some observations for understanding stress regime changes during hydraulic stimulations using 4D tomography

    NASA Astrophysics Data System (ADS)

    Calo, M.; Dorbath, C.; Cornet, F.; Cuenot, N.

    2011-12-01

    During the last decade three deep wells (GPK2, GPK3, and GPK4) were drilled to a depth of about 5000 m at the Enhanced Geothermal System (EGS) site of Soultz-sous-Forêts (Alsace, France). All the wells were stimulated through high-pressure hydraulic injections. Several thousands of micro-earthquakes with Duration Magnitude ranging from -0.9 to 2.9 were produced. The induced earthquakes were located by downhole and surface seismic stations. The wells behaved differently during and after the stimulations, as shown by several authors. We present here a comparison between new 4D seismic tomographies performed for the above mentioned stimulation tests. The velocity models have been obtained using the Double-Difference tomographic method (Zhang and Thurber 2003) and have been further improved with the post-processing WAM technique (Calo' et al., 2009, 2011). For each stimulation test, the subsetting of the data was performed by taking into account injection parameters (the injected flow rate and the wellhead pressure). In this work we discuss some important steps observed during and after the injections. A first observation is that low velocity anomalies were centered around the wells when stimulations started and then disappeared just after strong changes in the injected flow rate. We interpret these changes in seismic properties as transient changes in the stress regime during the stimulations. Furthermore, as shown by the seismic velocity models, pre-existing fracture network played a fundamental role on the intensity and distribution of the observed velocity anomalies. Indeed we observe that low velocity anomalies are much less evident and moved away from the well when documented large pre-exiting fractures cross the openhole part of the well. In particular, we observed this pattern for the models calculated with the data of the GPK3 stimulation. Thanks to the improvement and the reliability of these new velocity models, new discussions about the mechanical processes that occurred during the stimulations has been opened.

  19. Prospects of international trade in irradiated foods

    NASA Astrophysics Data System (ADS)

    Loaharanu, P.

    Irradiation is gaining recognition as a physical process for reducing food losses, enhancing hygienic quality of food and facilitating food trade. At present, 36 countries have approved the use of irradiation for processing collectively over 40 food items either on an unconditional or restricted basis. Commercial use of irradiated foods and food ingredients is being carried out in 22 countries. Technology transfer on food irradiation is being intensified to local industry in different regions. worldwide, a total of 40 commercial/demonstration irradiators available for treating foods have been or are being constructed. Acceptance and control of international trade in irradiated foods were discussed at the International Conference on the Acceptance, Control of and Trade in Irradiated Food, jointly convened by FAO, IAEA, WHO and ITC-UNCTAD/GATT in Geneva, Switzerland, 12-16 December 1988. An "International Document on Food Irradiation" was adopted by consensus at this Conference which will facilitate wider acceptance and control of international trade in irradiated foods.

  20. Investigation of irradiated soil byproducts.

    PubMed

    Brey, R R; Rodriguez, R; Harmon, J F; Winston, P

    2001-01-01

    The high dose irradiation of windblown soil deposited onto the surface of spent nuclear fuel is of concern to long-term fuel storage stability. Such soils could be exposed to radiation fields as great as 1.08 x 10(-3) C/kg-s (15,000 R/hr) during the 40-year anticipated period of interim dry storage prior to placement at the proposed national repository. The total absorbed dose in these cases could be as high as 5 x 10(7) Gy (5 x 10(9) rads). This investigation evaluated the potential generation of explosive or combustible irradiation byproducts during this irradiation. It focuses on the production of radiolytic byproducts generated within the pore water of surrogate clays that are consistent with those found on the Idaho National Engineering and Environmental Laboratory. Synthesized surrogates of localized soils containing combinations of clay, water, and aluminum samples, enclosed within a stainless steel vessel were irradiated and the quantities of the byproducts generated measured. Two types of clays, varying primarily in the presence of iron oxide, were investigated. Two treatment levels of irradiation and a control were investigated. An 18-Mev linear accelerator was used to irradiate samples. The first irradiation level provided an absorbed dose of 3.9 x 10(5)+/-1.4 x 10(5)Gy (3.9 x 10(7)+/-1.4 x 10(7) rads) in a 3-h period. At the second irradiation level, 4.8 x 10(5)+/-2.0 x 10(5)Gy (4.8 x 10(7)+/-2.0 x 10(7) rads) were delivered in a 6-h period. When averaged over all treatment parameters, irradiated clay samples with and without iron (III) oxide (moisture content = 40%) had a production rate of hydrogen gas that was a strong function of radiation-dose. A g-value of 5.61 x 10(-9)+/-1.56 x 10(-9) mol/J (0.054+/-0.015 molecules/100-eV) per mass of pore water was observed in the clay samples without iron (III) oxide for hydrogen gas production. A g-value of 1.07 x 10(-8)+/-2.91 x 10(-9) mol/J (0.103+0.028 molecules/100-eV) per mass of pore water was observed in the iron (III) oxide containing clay samples for hydrogen gas production. This value was noticeably larger when the samples were spiked with both KCl and KNO3 salts. The ratio of oxygen to nitrogen gas was observed to increase as a function of absorbed dose particularly in the presence of both KCl and KNO3 salts. The creation of radiolytic byproducts produced an observable but small increase in headspace pressure. Temperature increases during irradiation were not observed. Additionally, KCl and KNO3 salts added to the clays enhanced nitrite production as a function of radiation-dose and the type of clay considered. The addition of aluminum to these samples had no statistically discernable impact at the alpha = 0.05 level. Generation of the irradiation products, hydrogen peroxide and hydrogen gas also depended upon the type of clay irradiated and the presence of both KCl and KNO3 salts and the total dose received. PMID:11478625

  1. Healing in the irradiated wound

    SciTech Connect

    Miller, S.H.; Rudolph, R. (Univ. of California, San Diego (USA))

    1990-07-01

    Poor or nonhealing of irradiated wounds has been attributed to progressive obliterative endarteritis. Permanently damaged fibroblasts may also play an important part in poor healing. Regardless of the cause, the key to management of irradiated skin is careful attention to prevent its breakdown and conservative, but adequate, treatment when wounds are minor. When wounds become larger and are painful, complete excision of the wound or ulcer is called for and coverage should be provided by a well-vascularized nonparasitic distant flap.16 references.

  2. Irradiated icecreams for immunosuppressed patients

    NASA Astrophysics Data System (ADS)

    Adeil Pietranera, M. S.; Narvaiz, P.; Horak, C.; Kairiyama, E.

    2003-04-01

    Vanilla, raspberry, peach and milk jam icecreams were gamma irradiated with 3, 6 and 9 kGy doses in order to achieve microbial decontamination. Microbiological, sensory and some chemical analysis (acidity, peroxides, ultraviolet and visible absorption, thin-layer chromatography and sugar determination) were performed. Water-based icecreams (raspberry and peach) were more resistant to gamma radiation than cream-based ones (vanilla and milk jam). Gamma irradiation with 3 kGy reduced remarkably the microbial load of these icecreams without impairing the quality of the icecreams.

  3. Solar Irradiance: Observations, Proxies, and Models (Invited)

    NASA Astrophysics Data System (ADS)

    Lean, J.

    2013-12-01

    Solar irradiance has been measured from space for more than thirty years. Variations in total (spectrally integrated) solar irradiance associated with the Sun's 11-year activity cycle and 27-day rotation are now well characterized. But the magnitude, and even the sign, of spectral irradiance changes at near ultraviolet, visible and near infrared wavelengths, remain uncertain on time scales longer than a few months. Drifts in the calibration of the instruments that measure solar irradiance and incomplete understanding of the causes of irradiance variations preclude specification of multi-decadal solar irradiance variations with any confidence, including whether, or not, irradiance levels were lower during the 2008-2009 anomalously low solar activity minimum than in prior minima. The ultimate cause of solar irradiance variations is the Sun's changing activity, driven by a sub-surface dynamo that generates magnetic features called sunspots and faculae, which respectively deplete and enhance the net radiative output. Solar activity also alters parameters that have been measured from the ground for longer periods and with greater stability than the solar irradiance datasets. The longest and most stable such record is the Sun's irradiance at 10.7 cm in the radio spectrum, which is used frequently as a proxy indicator of solar irradiance variability. Models have been developed that relate the solar irradiance changes - both total and spectral - evident in extant databases to proxies chosen to best represent the sunspot darkening and facular brightening influences. The proxy models are then used to reconstruct solar irradiance variations at all wavelengths on multi-decadal time scales, for input to climate and atmospheric model simulations that seek to quantity the Sun's contribution to Earth's changing environment. This talk provides an overview of solar total and spectral irradiance observations and their relevant proxies, describes the formulation and construction of proxy models of solar irradiance variability, compares the observed and modeled irradiance variations on multiple time scales, and illustrates terrestrial applications of solar irradiance variability models.

  4. Statistical criteria for characterizing irradiance time series.

    SciTech Connect

    Stein, Joshua S.; Ellis, Abraham; Hansen, Clifford W.

    2010-10-01

    We propose and examine several statistical criteria for characterizing time series of solar irradiance. Time series of irradiance are used in analyses that seek to quantify the performance of photovoltaic (PV) power systems over time. Time series of irradiance are either measured or are simulated using models. Simulations of irradiance are often calibrated to or generated from statistics for observed irradiance and simulations are validated by comparing the simulation output to the observed irradiance. Criteria used in this comparison should derive from the context of the analyses in which the simulated irradiance is to be used. We examine three statistics that characterize time series and their use as criteria for comparing time series. We demonstrate these statistics using observed irradiance data recorded in August 2007 in Las Vegas, Nevada, and in June 2009 in Albuquerque, New Mexico.

  5. TOXICOLOGICAL SAFETY OF IRRADIATED FOODS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Irradiation of food and agricultural products is allowed in over 60 countries around the world, and has only been allowed only after extensive testing for toxicological safety. Studies conducted over a 50 year period found no detectable increases in the risk of cancer or birth defects associated wi...

  6. [Ovarian irradiation in recurrent endometriosis].

    PubMed

    Kochbati, L; Chaari, N; Néji, K; Ben Romdhane, N-K; Ben Amara, F; Besbes, M; Maalej, M

    2005-09-01

    We describe a case of a young woman with a history of an aplastic anaemia in which pelvic radiotherapy was used successfully in the management of a recurrent and inoperable endometriosis. The use of therapeutic pelvic or ovarian irradiation in endometriosis may be considered, when surgical and medical treatments have been exhausted and have failed. PMID:16176883

  7. Irradiation enhancement of biomass conversion

    NASA Astrophysics Data System (ADS)

    Smith, G. S.; Kiesling, H. E.; Galyean, M. L.; Bader, J. R.

    The vast supply of cellulosic agricultural residues and industrial by-products that is produced each year is a prospective resource of biomass suitable for conversion to useful products such as feedstock for the chemicals industry and feedstuffs for the livestock industry. Conversions of such biomass is poor at present, and utilization is inefficient, because of physio-chemical barriers to biological degradation and (or) anti-quality components such as toxicants that restrict biological usages. Improvements in biodegradability of ligno-cellulosic materials have been accomplished by gamma-ray and electron-beam irradiation at intermediate dosage (˜ 50 Mrad; .5 MGy); but applications of the technology have been hampered by questionable interpretations of results. Recent research with organic wastes such as sewage sludge and straw suggests opportunity for important applications of irradiation technology in enhancement of biomass conversion. Data from experiments using irradiated straw as feed for ruminants are presented and discussed in relation to research on prospective usage of sewage products as feed for ruminants. Findings are discussed in regard to prospective applications in industrial fermentation processes. Possible usage of irradiation technology for destruction of toxicants in exotic plants is considered in regard to prospective new feedstuffs.

  8. Food irradiation: regulations and acceptance

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Food irradiation is an effective technology for reducing harmful pathogens and insect pests on meats, poultry, seafood and fruits and vegetables. Although it is one of the most extensively researched nonthermal food processing technologies, its commercial adoption remains relatively limited. Regulat...

  9. Food Irradiation Research and Technology

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Food Irradiation is a safe and effective U.S. Food and Drug Administration (FDA) approved process that can be used to disinfest or delay the maturation of fruits and vegetables, improve the microbiological safety of shellfish, eggs, raw meat and poultry, spices, and seeds used for sprouting. FDA ap...

  10. Food Irradiation: Solution or Threat?

    NSDL National Science Digital Library

    1997-01-01

    This Consumers International Briefing Paper presents a less positive view of the process. CI is "a worldwide non-profit federation of consumer organisations." Previously approved for use on poultry and fruits and vegetables in the US, irradiation can kill disease-causing bacteria like Salmonella and Escherichia coli 0157:H7 (discussed in the Scout Report for Science and Engineering's In the News section, September 17, 1997), and molds and funguses that cause rot. With recent US Food and Drug Administration (FDA) approval, irradiation can now be used to process red meat (e.g., beef, pork, lamb, and byproducts). The process involves exposing food to a source of radiation such as gamma rays from radioactive cobalt 60, cesium 137, or x-rays. No radioactive material is added to the product, and the technique is routinely used on grains and spices, as well as for sterilizing disposable medical devices. In spite of a number of tests conducted over the last 30 years substantiating its safety, irradiation has not gained widespread public acceptance in the US. This is largely due to the public's general fear of processes utilizing radiation. Supporters of the technology claim that it will virtually eliminate food-borne illness in the US, while skeptics feel that technology such as steam treatment can accomplish adequate sterilization without the purported risks and public concern associated with irradiation.

  11. IMPROVEMENT OF PLASTICS BY IRRADIATION

    Microsoft Academic Search

    Lamm

    1960-01-01

    The improvement of plastics by irradiation depends on various mechanisms ; which are briefly described. Reticulation and polymerization, which are ascribed ; principally to the formation of radicals and subsequent chain reactions, are ; discussed. As concrete examples, polyethylene reticulation with its advantages ; (for example, improvement of the heat resistance), rubber vulcanization with its ; problems (attainment of a

  12. Food irradiation research and technology

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Food Irradiation is a safe and effective U.S. Food and Drug Administration (FDA) approved process that can be used to disinfest or delay the maturation of fruits and vegetables, improve the microbiological safety of shellfish, eggs, raw meat and poultry, spices, and seeds used for sprouting. FDA ap...

  13. MFR PAPER 1135 Irradiation of

    E-print Network

    rancidity in peanut oil. Although some work has been done on the development of radiation- sterilized fish irradiation processing even at low doses. The present inves- tigation was made , therefore, to study process. MATERIALS AND METHODS Fresh, headless, white shrimp, Penaeus setiferus, of commercial size (26

  14. Multispecimen dual-beam irradiation damage chamber

    Microsoft Academic Search

    N. H. Packan; R. A. Buhl

    1980-01-01

    An irradiation damage chamber that can be used to rapidly simulate fast neutron damage in fission or fusion materials has been designed and constructed. The chamber operates in conjunction with dual Van de Graaff accelerators at ORNL to simulate a wide range of irradiation conditions, including pulsed irradiation. Up to six experiments, each with up to nine 3-mm disk specimens,

  15. Irradiation-induced phenomena in carbon

    E-print Network

    Krasheninnikov, Arkady V.

    Chapter 1 Irradiation-induced phenomena in carbon nanotubes To appear in "Chemistry of Carbon@acclab.helsinki.fi 1 #12;2CHAPTER 1. IRRADIATION-INDUCED PHENOMENA IN CARBON NANOTUBES #12;Contents 1 Irradiation-induced phenomena in carbon nanotubes 1 1.1 Introduction

  16. Biological effects of ultraviolet irradiation on bees

    SciTech Connect

    Es`kov, E.K. [Ryazan` State Pedagogical Univ. (Russian Federation)

    1995-09-01

    The influence of natural solar and artificial ultraviolet irradiation on developing bees was studied. Lethal exposures to irradiation at different stages of development were determined. The influence of irradiation on the variability of the morphometric features of bees was revealed. 5 refs., 1 fig.

  17. Irradiation hardening of reduced activation martensitic steels

    NASA Astrophysics Data System (ADS)

    Kimura, A.; Morimura, T.; Narui, M.; Matsui, H.

    1996-10-01

    Irradiation response on the tensile properties of 9Cr?2W steels has been investigated following FFTF/MOTA irradiations at temperatures between 646 and 873 K up to doses between 10 and 59 dpa. The largest irradiation hardening accompanied by the largest decrease in the elongation is observed for the specimens irradiated at 646 K at doses between 10 and 15 dpa. The irradiation hardening appears to saturate at a dose of around 10 dpa at the irradiation temperature. No hardening but softening was observed in the specimens irradiated at above 703 K to doses of 40 and 59 dpa. Microstructural observation by transmission electron microscope (TEM) revealed that the dislocation loops with the a<100> type Burgers vector and small precipitates which were identified to be M 6C type carbides existed after the irradiation at below 703 K. As for the void formation, the average size of voids increased with increasing irradiation temperature from 646 to 703 K. No voids were observed above 703 K. Irradiation softening was attributed to the enhanced recovery of martensitic structure under the irradiation. Post-irradiation annealing resulted in hardening by the annealing at 673 K and softening by the annealing at 873 K.

  18. Calculation of direct normal irradiation from global horizontal irradiation

    NASA Astrophysics Data System (ADS)

    Rodrigo, Pedro; Pérez-Higueras, Pedro J.; Almonacid, Florencia; Hontoria, Leocadio; Fernández, Eduardo F.; Rus, Catalina; Fernández, Juan I.; Gómez, Pedro; Almonacid, Gabino

    2012-10-01

    Concentrator Photovoltaic (CPV) systems only work with the Direct Normal Irradiance (DNI), so a knowledge of DNI data is required for the design and evaluation of these kinds of systems. DNI is not always measured at ground meteorological stations due to equipment costs. In recent years, several spatial databases that estimate DNI from satellite data have been developed. These databases are a very useful tool for CPV applications. However, the databases present uncertainty and provide different values of DNI. This lack of DNI data and the uncertainty of available data contrast with the availability of reliable global horizontal irradiation data, which is easy to find or measure. In this paper, a simple procedure for estimating DNI from global horizontal irradiation is presented. It does not try to improve the existing methods, but meets the basic requirements for the analysis of CPV systems. The method can be easily implemented in a spreadsheet or in computer programs in renewable energy and its accuracy is similar than that of the existing databases.

  19. Hepatobiliary kinetics after whole-body irradiation

    SciTech Connect

    Durakovic, A.

    1986-09-01

    The purpose of this investigation was to study hepatobiliary kinetics after whole-body gamma irradiation. Two groups of nine male beagle dogs were irradiated with a single whole body dose of 4- and 8-Gy cobalt-60 photons. Each animal was injected with 2 mCi Tc-99m DISIDA and scintigraphic studies were obtained with a gamma camera with a parallel hole multipurpose collimator. The parameters studied included: peak activity of the liver and gall bladder and gall bladder and intestinal visualization from the time of Tc-99m DISIDA administration. Total and indirect bilirubin, LDH, SGOT, and SGPT determined as baseline studies before irradiation and at different time intervals after irradiation were not changed in irradiated animals. Whole body Co-60 irradiation with 4 and 8 Gy produced no significant changes in the Tc-99m DISIDA visualization of the gall bladder or in the peak activity in the gall bladder or the liver 1 and 7 days after irradiation. Intestinal visualization occurred significantly earlier in 8 Gy Co-60 irradiated animals on both day 1 and day 7 post irradiation, compared to baseline values where it was never observed before 195.0 minutes. Gall bladder emptying is significantly accelerated after 8 Gy but not after 4-Gy Co-60 gamma irradiation. These observations suggest that gamma irradiation stimulates gall bladder contractility without modifying intrahepatic biliary kinetics.

  20. Lyra Irradiation Experiments:. Neutron Metrology and Dosimetry

    NASA Astrophysics Data System (ADS)

    Acosta, B.; Debarberis, L.

    2009-08-01

    LYRA is a dedicated rig for materials irradiation in the High Flux Reactor in Petten, the Netherlands. The LYRA facility is located at the HFR's Pool Side Facility. The irradiation rig comprises a tungsten gamma shielding, and the irradiation capsule itself. The capsule is foreseen of a heater box that, forming a small oven, allows for irradiation of large number of samples at very low thermal gradients and if required in-pile annealing. LYRA has been designed for the purpose of studying the irradiation damage of nuclear reactor pressure vessel materials. LYRA began its operation in 1997 and has been now operated for 10 years, holding already 10 irradiation campaigns. In this paper the different LYRA irradiation experiments, their results from the neutron metrology as well as the doses build-up point of view are presented.

  1. Solar spectral irradiance at ground level

    NASA Technical Reports Server (NTRS)

    Mecherikunnel, A. T.; Richmond, J. C.

    1978-01-01

    Available quantitative data on solar total and spectral irradiance is examined in the context of utilization of solar irradiance for terrestrial applications of solar energy. A brief review is given on the extraterrestrial solar total and spectral irradiance values. Computed values of solar spectral irradiance at ground level for different air mass values and various levels of atmospheric pollution or turbidity are also presented. Wavelengths are given for computation of solar absorptance, transmittance and reflectance by the 100-selected-ordinate method and by the 50-selected-ordinate method from air mass two solar spectral irradiance for the four degrees of atmospheric pollution. Total solar spectral irradiance measured with a prism monochromator is examined to evaluate the direct solar spectral irradiance for a surface normal to the sun's rays and to compare the computed spectrum with the experimentally observed one.

  2. GTL-1 Irradiation Summary Report

    SciTech Connect

    D. M. Perez; G. S. Chang; N. E. Woolstenhulme; D. M. Wachs

    2012-01-01

    The primary objective of the Gas Test Loop (GTL-1) miniplate experiment is to confirm acceptable performance of high-density (i.e., 4.8 g-U/cm3) U3Si2/Al dispersion fuel plates clad in Al-6061 and irradiated under the relatively aggressive Booster Fast Flux Loop (BFFL) booster fuel conditions, namely a peak plate surface heat flux of 450 W/cm2. As secondary objectives, several design and fabrication variations were included in the test matrix that may have the potential to improve the high-heat flux, high-temperature performance of the base fuel plate design.1, 2 The following report summarizes the life of the GTL-1 experiment through end of irradiation, including as-run neutronic analysis, thermal analysis and hydraulic testing results.

  3. Surface ultraviolet irradiance from OMI

    Microsoft Academic Search

    Aapo Tanskanen; Nickolay A. Krotkov; Jay R. Herman; Antti Arola

    2006-01-01

    The Ozone Monitoring Instrument (OMI) onboard the NASA Earth Observing System (EOS) Aura spacecraft is a nadir-viewing spectrometer that measures solar reflected and backscattered light in a selected range of the ultraviolet and visible spectrum. The instrument has a 2600-km-wide viewing swath, and it is capable of daily, global contiguous mapping. We developed and implemented a surface ultraviolet (UV) irradiance

  4. RERTR-6 Irradiation Summary Report

    SciTech Connect

    D. M. Perez; M. A. Lillo; G. S. Chang; G. A. Roth; N. E. Woolstenhulme; D. M. Wachs

    2011-12-01

    The Reduced Enrichment for Research and Test Reactor (RERTR) experiment RERTR-6 was designed to evaluate several modified fuel designs that were proposed to address the possibility of breakaway swelling due to porosity within the (U. Mo) Al interaction product observed in the full-size plate tests performed in Russia and France1. The following report summarizes the life of the RERTR-6 experiment through end of irradiation, including as-run neutronic analyses, thermal analyses and hydraulic testing results.

  5. RERTR-8 Irradiation Summary Report

    SciTech Connect

    D. M. Perez; M. A. Lillo; G. S. Chang; G. A. Roth; N. E. Woolstenhulme; D. M. Wachs

    2011-12-01

    The Reduced Enrichment for Research and Test Reactor (RERTR) experiment RERTR-8, was designed to test monolithic mini-fuel plates fabricated via hot isostatic pressing (HIP), the effect of molybdenum (Mo) content on the monolithic fuel behavior, and the efficiency of ternary additions to dispersion fuel particles on the interaction layer behavior at higher burnup. The following report summarizes the life of the RERTR-8 experiment through end of irradiation, including as-run neutronic analysis, thermal analysis and hydraulic testing results.

  6. RERTR-13 Irradiation Summary Report

    SciTech Connect

    D. M. Perez; M. A. Lillo; G. S. Chang; D. M. Wachs; G. A. Roth; N. E. Woolstenhulme

    2012-09-01

    The Reduced Enrichment for Research and Test Reactor (RERTR) experiment RERTR-13 was designed to assess performance of different types of neutron absorbers that can be potentially used as burnable poisons in the low enriched uranium-molybdenum based dispersion and monolithic fuels.1 The following report summarizes the life of the RERTR-13 experiment through end of irradiation, including as-run neutronic analysis results, thermal analysis results and hydraulic testing results.

  7. Licensing a new industrial irradiator.

    PubMed

    Bates, Nicolas K; Entwistle, Frederick B

    2010-02-01

    After nearly three decades of medical product sterilization, 3M launched a major new project to build and license an irradiator facility. 3M Corporate Health Physics was responsible for the licensing aspect of this project. The licensing process consisted of six amendments, over 30 submissions to the U.S. Nuclear Regulatory Commission (U.S. NRC) and four U.S. NRC site visits. It took approximately 22 months to complete. The six license amendments are reviewed and several of the submissions are discussed. These include 3M's response to the U.S. NRC's interest in the shielding calculations used for the bioshield, the development of a protocol of radiation safety system test methods, and an analysis to show that a dropped cask during loading operations would not fall on sealed sources. A number of lessons were learned during the course of licensing the new irradiator. Among these were the importance of understanding the U.S. NRC license reviewer's perspective, the need to thoroughly review the irradiator manufacturer's licensing package during project negotiations, the benefits of leaving the Health Physics Office and meeting with the non-health physicists involved in the project, and the necessity of maintaining the solid relationships that already existed with the site Radiation Safety Officer and Sterilization Engineer. PMID:20065665

  8. Source mechanisms of micro-earthquakes induced in hydraulic fracturing experiment at the HDR site Soultz-sous-Forêts (Alsace) in 2003 and their temporal and spatial variations

    NASA Astrophysics Data System (ADS)

    Horálek, J.; Dorbath, L.; Jechumtálová, Z.; Šílený, J.

    2009-04-01

    We have investigated source mechanisms of microearthquakes induced in the 2003 hydrofracturing experiment in the GPK3 borehole of the Soultz-sous-Forêts Hot Dry Rock facility (located in the Rhine Graben) and their time and space distribution. During this massive hydrofatcturing a total of 34000m3 fluids with the wellhead pressure up to18 MPa were injected and about 5000 microearthquakes in the magnitude range of -0.9 ? M ? 2.9 were recorded by the surface local network. Depths of induced events varied between 3.5 km and 5.5 km. Seismic activity continued ten days after the injection shut in, during this period the largest events occurred. A peculiarity of the 2003-seismicity was a relatively high rate of larger microearthquakes which occurred during whole experiment. We investigated set of 45 microearthquakes of magnitudes M ? 1.6 to 2.9 covering the whole injection both in time and space. Unconstrained moment tensor (MT) expression of the mechanism was applied, allowing description of a general system of dipoles, i.e. both double-couple (DC) and non-DC sources like tensile fractures. Each of the resultant moment tensors was tested for stability to the reduction of the stations used, incorrectness of the amplitude readings due to distortion by noise, and structure mismodelling. The resultant moment tensors indicate dominance of the double-couple components - mostly larger than 90%, minor non-double-couple parts were found to be insignificant; this implies that all the larger microearthquakes were nearly pure shear slips. The focal mechanisms show fairly large variability and are of a normal dip-slip, oblique normal to strike-slip types. The T-axes are fairly stable, being concentrated sub-horizontally roughly in the E-W direction. On the contrary, P-axes plunge varies largely from horizontal to vertical being well constrained in the N-S direction. This points out that the Soultz upper crust is the extension stress regime (similar magnitudes of the maximum and the medium stresses, 1 and 2), in which the normal dip-slip, oblique normal and strike slip faulting is possible. The temporal and spatial distribution of events investigated indicates a link of induced seismicity to two fault segments, I and II in our notation, showing different source mechanism pattern. Segment I located close to the GPK3-borehole was active during the whole experiments while segment II only after the GP3-shut in. The largest events occurred within both segments, a few days after the GPK3 shut in. This however shows that the 2003-Soultz seismic activity developed to a great extent independently of the injection strategy. Injected fluids acts only to decrease the Coulomb friction by reducing the normal stress on the fractures and to 'lubricate' the fault walls, enhancing a shear slip along the pre-existing fractures. In this respect the 2003-Soultz seismic activity resembles tectonic foreshock-mainshock-aftershock earthquake sequence. Furthermore we infer that general assumption that highly pressurized fluids generate tensile fracturing of the rock mass need not be correct. It holds only if the injection pressure is higher than the tensile strength of the material.

  9. 2-alkylcyclobutanones as irradiation dose indicators in irradiated ground beef patties.

    PubMed

    Gadgil, Priyadarshini; Hachmeister, Kathleen A; Smith, J Scott; Kropf, Donald H

    2002-09-25

    Alkylcyclobutanones have been recognized as chemical markers of irradiated lipid-containing foods since 1970. They are important because they are produced solely as a result of irradiation and not any other processing method. This study investigated the formation of 2-dodecylcyclobutanone (2-DCB) and 2-tetradec-5'-enylcyclobutanone (2-TDCB) in irradiated ground beef patties from commercial and noncommercial sources. Patties were irradiated using a (60)C source (gamma-irradiation) and electron beam irradiation, at five targeted absorbed doses of 0.5, 1.0, 2.5, 5.0, and 7.0 kGy. Commercially available irradiated patties were also studied. A supercritical fluid extraction (SFE) procedure was optimized and used for the extraction and isolation of the alkylcyclobutanones. Samples can be used for extraction without a prior cleanup step, which makes this procedure rapid and convenient to use. Identification and quantitation of the cyclobutanones were done by gas chromatography-mass spectroscopy. 2-DCB was detected in all of the irradiated samples (including commercial patties), and its concentration increased linearly with the irradiation dose. Electron beam irradiation produced a greater amount of 2-DCB compared to gamma-irradiation at dose levels >2.5 kGy. 2-TDCB was detected only at the two higher irradiation doses, whereas both marker compounds were not detected in the non-irradiated samples. PMID:12236709

  10. Irradiation preservation of seafood: Literature review

    SciTech Connect

    Molton, P.M.

    1987-10-01

    The application of gamma-irradiation for extending the shelf life of seafood has been of interest for many years. This report reviews a number of studies on seafood irradiation conducted over the past several years. Topics covered include seafood irradiation techniques and dosages, species applicability and differences, the effects of packaging on seafood preservation, and changes in organoleptic acceptability as a result of irradiation. Particular attention is given to radiation effects (likely and unlikely) of concern to the public. These include the potential for generation of toxic chemical products, botulinum toxin production, and other health concerns. No scientifically defensible evidence of any kind was found for any harmful effect of irradiation of seafoods at the doses being considered (less than 300 krad), and all indications are that irradiation is an acceptable and needed additional tool for seafood preservation. 49 refs., 14 figs., 14 tabs.

  11. Irradiation creep in simple binary alloys

    SciTech Connect

    Nagakawa, J.; Sethi, V.K.; Turner, A.P.L.

    1981-07-01

    Creep enhancement during 21-MeV deuteron irradiation was examined at 350/sup 0/C for two simple binary alloys with representative microstructures, i.e., solid-solution (Ni - 4 at. % Si) and precipitation-hardened (Ni - 12.8 at. % Al) alloys. Coherent precipitates were found to be very effective in suppressing irradiation-enhanced creep. Si solute atoms depressed irradiation creep moderately and caused irradiation hardening via radiation-induced segregation. The stress-dependence of irradiation creep in Ni - 4 at. % Si should a transition, which seems to reflect a change of mechanism from dislocation climb due to stress-induced preferential absorption (SIPA) to climb-controlled dislocation glide enhanced by irradiation.

  12. (Irradiation embrittlement of reactor pressure vessels)

    SciTech Connect

    Corwin, W.R.

    1990-09-24

    The traveler served as a member of the two-man US Nuclear Regulatory Commission sponsored team who visited the Prometey Complex in Leningrad to assess the potential for expanded cooperative research concerning integrity of the primary pressure boundary in commercial light-water reactors. The emphasis was on irradiation embrittlement, structural analysis, and fracture mechanics research for reactor pressure vessels. At the irradiation seminar in Cologne, presentations were made by German, French, Finnish, Russian, and US delegations concerning many aspects of irradiation of pressure vessel steels. The traveler made presentations on mechanisms of irradiation embrittlement and on important aspects of the Heavy-Section Steel Irradiation Program results of irradiated fracture mechanics tests.

  13. Early esophageal carcinoma treated with intracavitary irradiation

    SciTech Connect

    Hishikawa, Y.; Tanaka, S.; Miura, T.

    1985-08-01

    Five patients with early esophageal carcinoma were treated by 6-12 Gy of intracavitary irradiation following 50-60 Gy of external irradiation as a boost therapy. Surgery was not performed in these cases. None of the patients had local recurrence after radiation therapy, as demonstrated by esophagography and endoscopy. Three patients have been alive for 1-3 years 10 months. Esophageal ulceration induced by intracavitary irradiation has occurred in three of the five patients; however, intracavitary irradiation is still a beneficial treatment because of its efficacy in controlling local lesions and because radiation ulceration can eventually be cured. Intracavitary irradiation is recommended to follow external irradiation as a boost therapy for the treatment of early esophageal carcinoma.

  14. Electron spin resonance identification of irradiated fruits

    NASA Astrophysics Data System (ADS)

    Raffi, Jacques J.; Agnel, Jean-Pierre L.

    The electron spin resonance spectrum of achenes, pips, stalks and stones from irradiated fruits (strawberry, raspberry, red currant, bilberry, apple, pear, fig, french prune, kiwi, water-melon and cherry) always displays, just after ?-treatment, a weak triplet ( aH?30 G) due to a cellulose radical; its left line (lower field) can be used as an identification test of irradiation, at least for strawberries, rapsberries, red currants or bilberries irradiated in order to improve their storage time.

  15. Ion irradiation-induced anisotropic plastic deformation

    E-print Network

    Polman, Albert

    in silica made by ion irradiation of core-shell colloidal particles 114 9.7 Conclusions 116 Summary 118.3 This thesis 14 2 Anisotropic plastic deformation of colloidal silica particles under 4 MeV Xe ion irradiation.3.1 Silica colloids 31 3.3.2 Other materials 34 3.4 Conclusions 37 4. Ion irradiation-induced anisotropic

  16. Grafting of styrene into pre-irradiated fluoropolymer films: Influence of base material and irradiation temperature

    NASA Astrophysics Data System (ADS)

    Lappan, Uwe; Geißler, Uwe; Gohs, Uwe; Uhlmann, Steffi

    2010-10-01

    In this study, the influence of irradiation temperature on mechanical properties of three fluoropolymers and on grafting of styrene into the polymers by the pre-irradiation method was investigated. Electron paramagnetic resonance spectroscopy and infrared spectroscopy were used to characterize the irradiated polymers regarding trapped radical species and changes in the chemical structure, respectively. For poly(tetrafluoroethylene-co-perfluoropropyl vinyl ether) (PFA) the irradiation temperature was found to be an important factor for tensile strength and elongation at break of the pre-irradiated film. No strong effect of irradiation temperature on the mechanical properties was noticed for poly(tetrafluoroethylene-co-ethylene) (ETFE); however the yield of grafting drops at high irradiation temperatures. Finally, mechanical properties of poly(tetrafluoroethylene) (PTFE) were found to be dramatically altered, even if the film was irradiated at elevated temperature.

  17. Irradiation Testing of Ultrasonic Transducers

    SciTech Connect

    Daw, Joshua; Tittmann, Bernhard; Reinhardt, Brian; Kohse, Gordon E.; Ramuhalli, Pradeep; Montgomery, Robert O.; Chien, Hual-Te; Villard, Jean-Francois; Palmer, Joe; Rempe, Joy

    2013-12-01

    Ultrasonic technologies offer the potential for high accuracy and resolution in-pile measurement of a range of parameters, including geometry changes, temperature, crack initiation and growth, gas pressure and composition, and microstructural changes. Many Department of Energy-Office of Nuclear Energy (DOE-NE) programs are exploring the use of ultrasonic technologies to provide enhanced sensors for in-pile instrumentation during irradiation testing. For example, the ability of single, small diameter ultrasonic thermometers (UTs) to provide a temperature profile in candidate metallic and oxide fuel would provide much needed data for validating new fuel performance models. Other efforts include an ultrasonic technique to detect morphology changes (such as crack initiation and growth) and acoustic techniques to evaluate fission gas composition and pressure. These efforts are limited by the lack of existing knowledge of ultrasonic transducer material survivability under irradiation conditions. For this reason, the Pennsylvania State University (PSU) was awarded an Advanced Test Reactor National Scientific User Facility (ATR NSUF) project to evaluate promising magnetostrictive and piezoelectric transducer performance in the Massachusetts Institute of Technology Research Reactor (MITR) up to a fast fluence of at least 1021 n/cm2 (E> 0.1 MeV). The goal of this research is to characterize magnetostrictive and piezoelectric transducer survivability during irradiation, enabling the development of novel radiation tolerant ultrasonic sensors for use in Material and Test Reactors (MTRs). As such, this test will be an instrumented lead test and real-time transducer performance data will be collected along with temperature and neutron and gamma flux data. The current work bridges the gap between proven out-of-pile ultrasonic techniques and in-pile deployment of ultrasonic sensors by acquiring the data necessary to demonstrate the performance of ultrasonic transducers.

  18. Analytical screening studies on irradiated food packaging.

    PubMed

    Driffield, M; Bradley, E L; Leon, I; Lister, L; Speck, D R; Castle, L; Potter, E L J

    2014-01-01

    Foods may be irradiated in their final packaging and this process may affect the composition of the packaging and in turn affect the migration of substances into food. Headspace and liquid injection GC-MS and HPLC with time-of-flight MS have been used to identify and estimate levels of radiolytic products in irradiated finished plastic packaging materials. Fifteen retail packaging materials were studied. Investigations were carried out into the effect of different irradiation types (gamma and electron beam), irradiation doses (1, 3, 7 and 10 kGy) and dose rates (5 kGy s(-1) for electron beam and 0.4 and 1.85 kGy h(-1) for gamma) on the radiolytic products. Any differences seen in comparing the two ionising radiation types were attributed largely to the very different dose rates; for electron beam a 10 kGy dose was delivered in just 2 s whereas using gamma it took 5.4 h. Differences were also seen when comparing the same samples irradiated at different doses. Some substances were not affected by irradiation, others decreased in concentration and others were formed upon increasing doses of irradiation. These results confirm that irradiation-induced changes do occur in substances with the potential to migrate and that the safety of the finished packaging material following irradiation should be assessed. PMID:24215551

  19. Data on total and spectral solar irradiance

    NASA Technical Reports Server (NTRS)

    Mecherikunnel, A. T.; Gatlin, J. A.; Richmond, J. C.

    1983-01-01

    This paper presents a brief survey of the data available on solar constant and extraterrestrial solar spectral irradiance. The spectral distribution of solar radiation at ground surface, computed from extraterrestrial solar spectral irradiance for several air mass values and for four levels of atmospheric pollution, is also presented. The total irradiance at ground level is obtained by integration of the area under the spectral irradiance curves. It is significant that, as air mass increases or as turbidity increases, the amount of energy in the infrared relative to the total increases and that the energy in the UV and visible decreases.

  20. Food irradiation and airline catering

    SciTech Connect

    Preston, F.S.

    1988-04-01

    Food poisoning from contaminated airline food can produce serious consequences for airline crew and passengers and can hazard flight. While irradiation of certain foodstuffs has been practised in a number of countries for some years, application of the process has not been made to complete meals. This paper considers the advantages, technical considerations, costs and possible application to airline meals. In addition, the need to educate the public in the advantages of the process in the wake of incidents such as Chernobyl is discussed.

  1. Thymus irradiation for myasthenia gravis

    SciTech Connect

    Currier, R.D.; Routh, A.; Hickman, B.T.; Douglas, M.A.

    1983-01-01

    Twenty-eight patients with progressive myasthenia gravis without thymoma received treatment of 3000 rads (30 Gy) to the anterior mediastinum, and a followup was conducted for five to 18 years. Twenty-four patients had generalized myasthenia, and four had ocular myasthenia gravis. Twenty patients with generalized myasthenia survived the several month post-treatment period and improved, but four died during that period. The improvement lasted a median of 1.5 years, and older patients had longer remissions than younger patients. The four patients who had ocular myasthenia did not change after treatment. Mediastinal irradiation produces a temporary remission in generalized myasthenia.

  2. AFIP-6 Irradiation Summary Report

    SciTech Connect

    Danielle M Perez; M. A. Lillo; G. S. Chang; G. A. Roth; N. E. Woolstenhulme; D. M. Wachs

    2011-09-01

    The Advanced Test Reactor (ATR) Full size plate In center flux trap Position (AFIP) experiment AFIP-6 was designed to evaluate the performance of monolithic uranium-molybdenum (U-Mo) fuels at a length prototypic to that of the ATR fuel plates (45 inches in length). The AFIP-6 test was the first test with plates in a swaged condition with longer fuel zones of approximately 22.5 inches in length1,2. The following report summarizes the life of the AFIP-6 experiment through end of irradiation, including a brief description of the safety analysis, as-run neutronic analysis results, hydraulic testing results, and thermal analysis results.

  3. Food irradiation and airline catering.

    PubMed

    Preston, F S

    1988-04-01

    Food poisoning from contaminated airline food can produce serious consequences for airline crew and passengers and can hazard flight. While irradiation of certain foodstuffs has been practised in a number of countries for some years, application of the process has not been made to complete meals. This paper considers the advantages, technical considerations, costs and possible application to airline meals. In addition, the need to educate the public in the advantages of the process in the wake of incidents such as Chernobyl is discussed. PMID:3370047

  4. Irradiation distribution diagrams and their use for estimating collectable energy

    Microsoft Academic Search

    M Rönnelid; B Karlsson

    1997-01-01

    A method for summarising annual or seasonal solar irradiation data in irradiation distribution diagrams including both direct and diffuse irradiation is outlined. The practical use of irradiation distribution diagrams is discussed in the paper. Examples are given for the calculation of collectable irradiation on flat plate collectors or trough-like concentrators like the compound parabolic concentrator (CPC), and for the calculation

  5. Myeloablative Irradiation in Nonhuman Primates

    PubMed Central

    Watts, Korashon L.; Beard, Brian C.; Wood, Brent L.; Kiem, Hans-Peter

    2009-01-01

    Purpose We used total body irradiation (TBI) as conditioning for cord blood transplantation studies in pigtailed macaques. In these studies, different doses of TBI were explored to obtain optimal myelosuppression with acceptable radiation-related side effects. Methods Four macaques received TBI ranging from 800 to 1320 cGy, followed by standard post-transplant care. Hematopoietic recovery was monitored by CBC and donor contribution by VNTR analysis. Results Animals receiving 800 or 1020 cGy TBI tolerated the irradiation well with autologous recovery of neutrophils within 24 days. At a dose of 1200 cGy, neither autologous recovery nor extramedullary toxicity was observed. A fourth animal received 1320 cGy of TBI and suffered significant toxicity necessitating termination of the study. Conclusions We conclude that previously considered myeloablative doses of TBI allowed for autologous recovery in the pigtailed macaque, and that a dose of 1200 cGy may be most appropriate, providing both myeloablation and acceptable nonhematopoietic toxicities. PMID:19638102

  6. Updates to ISO 21348 (determining solar irradiances)

    NASA Astrophysics Data System (ADS)

    Tobiska, W. Kent

    2012-07-01

    The ISO 21348 (Determining Solar Irradiances) International Standard is going through a document update. A consensus solar spectrum, solar indices/proxies descriptions, solar model descriptions, and solar measurement descriptions are among the Annexes that are proposed to the standard. These topics will be reviewed and described. The International Standards Organization (ISO) published IS 21348 in 2007 after 7 years of development by the international scientific community. In ISO, documents are reviewed on a regular basis and reaffirmed, updated, or deleted according to the votes of national delegations represented in ISO. IS 21348 provides guidelines for specifying the process of determining solar irradiances. Solar irradiances are reported through products such as measurement sets, reference spectra, empirical models, theoretical models and solar irradiance proxies or indices. These products are used in scientific and engineering applications to characterize within the natural space environment solar irradiances that are relevant to space systems and materials. Examples of applications using input solar irradiance energy include the determination of atmospheric densities for spacecraft orbit determination, attitude control and re-entry calculations, as well as for debris mitigation and collision avoidance activity. Direct and indirect pressure from solar irradiance upon spacecraft surfaces also affects attitude control separately from atmospheric density effects. Solar irradiances are used to provide inputs for a) calculations of ionospheric parameters, b) photon-induced radiation effects, and c) radiative transfer modeling of planetary atmospheres. Input solar irradiance energy is used to characterize material properties related to spacecraft thermal control, including surface temperatures, reflectivity, absorption and degradation. Solar energy applications requiring a standard process for determining solar irradiance energy include i) solar cell power simulation, ii) material degradation, and iii) the development of lamps and filters for terrestrial solar simulators. A solar irradiance product certifies compliance with this process-based standard by following compliance criteria that are described in this International Standard.

  7. Hybridizability of gamma-irradiated lactic dehydrogenase

    Microsoft Academic Search

    1976-01-01

    The hybridizabilities of the gamma-irradiated chicken heart and pig muscle lactic dehydrogenases were estimated by hybridizing the irradiated enzymes with the unirradiated pig heart lactic dehydrogenase. The disc gel electrophoretic patterns of the inter- and intraspecific hybrids showed that the LDH activity of the pig heart isozyme band increased as a function of dose. This observation was analyzed upon the

  8. Immune reactivity after high-dose irradiation

    SciTech Connect

    Gassmann, W.; Wottge, H.U.; von Kolzynski, M.; Mueller-Ruchholtz, W.

    1986-03-01

    Immune reactivity after total-body irradiation was investigated in rats using skin graft rejection as the indicator system. After sublethal irradiation with 10.5 Gy (approximately 50% lethality/6 weeks) the rejection of major histocompatibility complex allogeneic skin grafts was delayed significantly compared with nonirradiated control animals (28 versus 6.5 days). In contrast, skin grafts were rejected after 7.5 days in sublethally irradiated animals and 7 days in lethally irradiated animals if additional skin donor type alloantigens--namely, irradiated bone marrow cells--were given i.v. either simultaneously or with a delay of not more than 24 hr after the above conditioning regimen. These reactions were alloantigen-specific. They were observed in six different strain combinations with varying donors and recipients. Starting on day 2 after irradiation, i.v. injection of bone marrow gradually lost its effectivity and skin grafts were no longer rejected with uniform rapidity; skin donor marrow given on days 4 or 8 did not accelerate skin graft rejection at all. These data show that for approximately 1-2 days after high-dose total-body irradiation rats are still capable of starting a vigorous immune reaction against i.v.-injected alloantigens. The phenomenon of impaired rejection of skin grafted immediately after high-dose irradiation appears to result from the poor accessibility of skin graft alloantigens during the early postirradiation phase when vascularization of the grafted skin is insufficient.

  9. Cherry Irradiation Studies. 1984 annual report

    SciTech Connect

    Eakin, D.E.; Hungate, F.P.; Tingey, G.L.; Olsen, K.L.; Fountain, J.B.; Burditt, A.K. Jr.; Moffit, H.R.; Johnson, D.A.; Lunden, J.D.

    1985-04-01

    Fresh cherries, cherry fruit fly larvae, and codling moth larvae were irradiated using the PNL cobalt-60 facility to determine the efficacy of irradiation treatment for insect disinfestation and potential shelf life extension. Irradiation is an effective disinfestation treatment with no significant degradation of fruit at doses well above those required for quarantine treatment. Sufficient codling moth control was achieved at projected doses of less than 25 krad; cherry fruit fly control, at projected doses of less than 15 krad. Dose levels up to 60 krad did not adversely affect cherry quality factors tested. Irradiation above 60 krad reduced the firmness of cherries but had no significant impact on other quality factors tested. Irradiation of cherries below 80 krad did not result in any significant differences in sensory evaluations (appearance, flavor, and firmness) in tests conducted at OSU. Irradiation up to 200 krad at a temperature of about 25/sup 0/C (77/sup 0/F) did not measurably extend shelf life. Irradiation at 500 krad at 25/sup 0/C (77/sup 0/F) increased mold and rotting of cherries tested. There is no apparent advantage of irradiation over low-temperature fumigation.

  10. Identification of irradiated apples for phytosanitary purposes

    NASA Astrophysics Data System (ADS)

    Horak, Celina I.; Di Giorgio, Marina; Kairiyama, Eulogia

    2009-07-01

    The irradiation treatment of fresh fruits and vegetables for phytosanitary purposes is a satisfactory alternative method to others like fumigation and cold and hot treatments. Its use is increasing in several countries, and at present its approval is under revision by the National Regulatory Authorities. To verify the control process, apart from irradiation and dosimetry certificates, National Authorities require complementary evidence to show the efficacy of this treatment, especially when the documentation is not clear. The irradiation of fresh fruits produces single and double fragmentation in the DNA molecule, which can be measured using the microgel electrophoresis of individual cell (comet assay). The purpose of this work was to evaluate if it is possible to identify the irradiated apples for phytosanitary purposes from the others that were not treated. The possibility to estimate the absorbed dose was also evaluated. The methodology was carried out on the cell suspension obtained from irradiated seed cells with incremental doses (100, 200 and 300 Gy). The irradiation treatment for phytosanitary purposes to avoid emergency of codling moth ( Cydia pomonella) is 200 Gy. The fragmentation produced in the irradiated samples was proportional with the incremental doses applied. These results show that with this methodology it can be determined if the apple was irradiated or not. This comet assay is a simple, economical and interesting method that can be used, in case of necessity, by the National Authorities.

  11. IRRADIATION FOR POSTHARVEST CONTROL OF QUARANTINE INSECTS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Interest in the use of irradiation as a phytosanitary treatment for agricultural commodities is growing worldwide, particularly since international IPPC and CODEX standards now endorse and facilitate trade based on this disinfestation method. Irradiation is broadly effective against insects and mite...

  12. Mechanical response of proton beam irradiated nitinol

    NASA Astrophysics Data System (ADS)

    Afzal, Naveed; Ghauri, I. M.; Mubarik, F. E.; Amin, F.

    2011-01-01

    The present investigation deals with the study of mechanical behavior of proton beam irradiated nitinol at room temperature. The specimens in austenitic phase were irradiated over periods of 15, 30, 45 and 60 min at room temperature using 2 MeV proton beam obtained from Pelletron accelerator. The stress-strain curves of both unirradiated and irradiated specimens were obtained using a universal testing machine at room temperature. The results of the experiment show that an intermediate rhombohedral (R) phase has been introduced between austenite and martensite phase, which resulted in the suppression of direct transformation from austenite to martensite (A-M). Stresses required to start R-phase ( ?RS) and martensitic phase ( ?MS) were observed to decrease with increase in exposure time. The hardness tests of samples before and after irradiation were also carried out using Vickers hardness tester. The comparison reveals that the hardness is higher in irradiated specimens than that of the unirradiated one. The increase in hardness is quite sharp in specimens irradiated for 15 min, which then increases linearly as the exposure time is increased up to 60 min. The generation of R-phase, variations in the transformation stresses ?RS and ?MS and increase in hardness of irradiated nitinol may be attributed to lattice disorder and associated changes in crystal structure induced by proton beam irradiation.

  13. Emerging issues in food irradiation research

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Ionizing radiation is used on a global basis to improve the phytosanitary and microbial safety and shelf-life of foods. In recent years progress has been made in the commercial application of irradiation to sterilize destructive invasive insects and to irradiate produce to improve its microbiologica...

  14. Generic Irradiation Quarantine Treatments: The Next Steps

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In 2006, USDA-APHIS published a landmark rule providing generic irradiation quarantine treatments. The rule approved irradiation doses of 150 Gy for any tephritid fruit fly and 400 Gy for all other insects except the pupa and adult stages of Lepidoptera. Therefore, if a pest risk assessment demonstr...

  15. Effect of gamma-irradiation on ripening papaya pectin

    Microsoft Academic Search

    Min Zhao; James Moy; Robert E. Paull

    1996-01-01

    Papaya (Carica papaya, L., var. Sunset) at three initial ripeness stages were irradiated with 0.25, 0.50, 0.75, 1.0, or 1.5 kGy gamma-irradiation and pectin changes during ripening determined. A significant linear relationship was found between irradiation dose and firmness immediately after irradiation. Irradiation had no effect on fruit skin or flesh color of papaya fruit irradiated at the 5 to

  16. Metabolic profiling by (1)H NMR of ground beef irradiated at different irradiation doses.

    PubMed

    Zanardi, Emanuela; Caligiani, Augusta; Palla, Luigi; Mariani, Mario; Ghidini, Sergio; Di Ciccio, Pierluigi Aldo; Palla, Gerardo; Ianieri, Adriana

    2015-05-01

    This work describes a metabolic profiling study of non-irradiated and irradiated beef (at 2.5, 4.5 and 8 kGy) using (1)H NMR and chemometrics. The assignment of all major NMR signals of the aqueous/methanolic extracts was performed. A comprehensive multivariate data analysis proved the ability to distinguish between the irradiated and non-irradiated beef. Classification trees revealed that three metabolites (glycerol, lactic acid esters and tyramine or a p-substituted phenolic compound) are important biomarkers for classification of the irradiated and non-irradiated beef samples. Overall, the achieved metabolomic results show that the changes in the metabolic profile of meat provide a valuable insight to be used in detecting irradiated beef. The use of the NMR-based approach simplifies sample preparation and decrease the time required for analysis, compared to available official analytical procedures. PMID:25637742

  17. Production of modified starches by gamma irradiation

    NASA Astrophysics Data System (ADS)

    Kang, Il-Jun; Byun, Myung-Woo; Yook, Hong-Sun; Bae, Chun-Ho; Lee, Hyun-Soo; Kwon, Joong-Ho; Chung, Cha-Kwon

    1999-04-01

    As a new processing method for the production of modified starch, gamma irradiation and four kinds of inorganic peroxides were applied to commercial corn starch. The addition of inorganic peroxides without gamma irradiation or gamma irradiation without the addition of inorganic peroxides effectively decreased initial viscosity, but did not sufficiently keep viscosity stable. The combination of adding ammonium persulfate (APS) and gamma irradiation showed the lowest initial viscosity and the best stability out of the tested four kinds of inorganic peroxides. Among the tested mixing methods of APS, soaking was found to be more effective than dry blending or spraying. Therefore, the production of modified starch with low viscosity as well as with sufficient viscosity stability became feasible by the control of gamma irradiation dose levels and the amount of added APS to starch.

  18. RERTR-7 Irradiation Summary Report

    SciTech Connect

    D. M. Perez; M. A. Lillo; G. S. Chang; G. A. Roth; N. E. Woolstenhulme; D. M. Wachs

    2011-12-01

    The Reduced Enrichment for Research and Test Reactor (RERTR) experiment RERTR-7A, was designed to test several modified fuel designs to target fission densities representative of a peak low enriched uranium (LEU) burnup in excess of 90% U-235 at peak experiment power sufficient to generate a peak surface heat flux of approximately 300 W/cm2. The RERTR-7B experiment was designed as a high power test of 'second generation' dispersion fuels at peak experiment power sufficient to generate a surface heat flux on the order of 230 W/cm2.1 The following report summarizes the life of the RERTR-7A and RERTR-7B experiments through end of irradiation, including as-run neutronic analyses, thermal analyses and hydraulic testing results.

  19. [Irradiation in stereotactic conditions: prerequisites].

    PubMed

    Maingon, P; Lisbona, A

    2014-10-01

    Indications of treatment by stereotactic body radiotherapy are dramatically increasing due to new potential indications. The conditions associated with the treatment delivery are multiple. The first step of the process is crucial. It is related to the validation of the indication proposed during the multidisciplinary meeting as regard the evidence-based proof of the concept. These emerging techniques mainly extracranial stereotactic body irradiation do not benefit from long-term evaluation in terms of efficiency as well as normal tissue late toxicities. Priority should be given to prospective independent clinical trials, validated by an independent scientific committee, performed under a relevant and well dedicated multicentric quality assurance program aiming to improve knowledge and selection of indications. The SFRO is still working with others professionals on the definition of the conditions for the implementation of such treatments and actively collaborates with the authorities to define the appropriate conditions to preserve the quality of the treatment delivery under these specific conditions. PMID:25179251

  20. AFIP-3 Irradiation Summary Report

    SciTech Connect

    Danielle M Perez; M. A. Lillo; G. S. Chang; G. A. Roth; N. E. Woolstenhulme; D. M. Wachs

    2012-03-01

    The Advanced Test Reactor (ATR) Full size plate In center flux trap Position (AFIP) experiment AFIP-3 was designed to evaluate the performance of monolithic fuels at a prototypic scale of 2.25 inches x 21.5 inches x 0.050 inches (5.75 cm x 54.6 cm x 0.13cm). The AFIP-3 experiment was fabricated by hot isostatic pressing (HIP) and consists of two plates, one with a zirconium (Zr) diffusion barrier and one with a silicon (Si) enhanced fuel/clad interface1,2. The following report summarizes the life of the AFIP-3 experiment through end of irradiation, including a brief description of the safety analysis, as-run neutronic analysis results, hydraulic testing results, and thermal analysis results.

  1. AFIP-3 Irradiation Summary Report

    SciTech Connect

    Danielle M Perez; M. A. Lillo; G. S. Chang; G. A. Roth; N. E. Woolstenhulme; D. M. Wachs

    2011-05-01

    The Advanced Test Reactor (ATR) Full size plate In center flux trap Position (AFIP) experiment AFIP-3 was designed to evaluate the performance of monolithic fuels at a prototypic scale of 2.25 inches x 21.5 inches x 0.050 inches (5.75 cm x 54.6 cm x 0.13cm). The AFIP-3 experiment was fabricated by hot isostatic pressing (HIP) and consists of two plates, one with a zirconium (Zr) diffusion barrier and one with a silicon (Si) enhanced fuel/clad interface1,2. The following report summarizes the life of the AFIP-3 experiment through end of irradiation, including a brief description of the safety analysis, as-run neutronic analysis results, hydraulic testing results, and thermal analysis results.

  2. AFIP-3 Irradiation Summary Report

    SciTech Connect

    Danielle M Perez

    2011-04-01

    The Advanced Test Reactor (ATR) Full size plate In center flux trap Position (AFIP) experiment AFIP-3 was designed to evaluate the performance of monolithic fuels at a prototypic scale of 2.25 inches x 21.5 inches x 0.050 inches (5.75 cm x 54.6 cm x 0.13cm). The AFIP-3 experiment was fabricated by hot isostatic pressing (HIP) and consists of two plates, one with a zirconium (Zr) diffusion barrier and one with a silicon (Si) enhanced fuel/clad interface1,2. The following report summarizes the life of the AFIP-3 experiment through end of irradiation, including a brief description of the safety analysis, as-run neutronic analysis results, hydraulic testing results, and thermal analysis results.

  3. AFIP-2 Irradiation Summary Report

    SciTech Connect

    Danielle M Perez

    2011-04-01

    The Advanced Test Reactor (ATR) Full size plate In center flux trap Position (AFIP) experiment AFIP-2 was designed to evaluate the performance of monolithic fuels at a prototypic scale of 2.25 inches x 21.5 inches x 0.050 inches (5.75 cm x 54.6 cm x 0.13cm). The AFIP-2 experiment was fabricated by friction bond (FB) and consists of two plates, one with a zirconium (Zr) diffusion barrier and one with a silicon (Si) enhanced fuel/clad interface1,2. The following report summarizes the life of the AFIP-2 experiment through end of irradiation, including a brief description of the safety analysis, as-run neutronic analysis results, hydraulic testing results, and thermal analysis results. The safety analyses performed for AFIP-2 are summarized in Table 5 of the following report.

  4. Intraluminal irradiation in bronchogenic carcinoma

    SciTech Connect

    Nori, D.; Hilaris, B.S.; Martini, N.

    1987-10-01

    Endobronchial tumors present a difficult therapeutic problem. Most often these patients have primary lung cancer and present with endobronchial disease following a definitive course of surgery and/or irradiation. The most common methods of treatment include transbronchial excision of tumor or laser coagulation. The improvement obtained from these procedures is usually limited to 2 or 3 months, and repeated treatments become more difficult and less effective. A number of brachytherapy radiation techniques have been developed to deliver localized radiation in higher doses without exceeding surrounding normal tissue tolerance. Intraluminal radiation with brachytherapy techniques consists of implantation of radioactive pellets into the tumor through a rigid or flexible bronchoscope or the use of afterloading removable implants with remote afterloading techniques. These procedures can be combined with laser therapy to obtain effective palliation and long-term tumor control. Initial results appear promising.

  5. RERTR-10 Irradiation Summary Report

    SciTech Connect

    D. M. Perez

    2011-05-01

    The Reduced Enrichment for Research and Test Reactor (RERTR) experiment RERTR-10 was designed to further test the effectiveness of modified fuel/clad interfaces in monolithic fuel plates. The experiment was conducted in two campaigns: RERTR-10A and RERTR-10B. The fuel plates tested in RERTR-10A were all fabricated by Hot Isostatic Pressing (HIP) and were designed to evaluate the effect of various Si levels in the interlayer and the thickness of the Zr interlayer (0.001”) using 0.010” and 0.020” nominal foil thicknesses. The fuel plates in RERTR-10B were fabricated by Friction Bonding (FB) with two different thickness Si layers and Nb and Zr diffusion barriers.1 The following report summarizes the life of the RERTR-10A/B experiment through end of irradiation, including as-run neutronic analysis results, thermal analysis results and hydraulic testing results.

  6. Irradiation growth in zirconium and its alloys

    NASA Astrophysics Data System (ADS)

    Rogerson, A.

    1988-10-01

    The UKAEA Northern Research Laboratories (Risley) have recently completed an underlying research study on irradiation growth in zirconium and its alloys. During this study, irradiation growth measurements have been made on a range of well-characterized single-crystal and polycrystalline iodide zirconium, commercial alloys Zircaloy-2 and Zr-2.5 wt% Nb, and high-purity zirconium-tin alloys in different metallurgical conditions following irradiation in the DIDO reactor at AERE Harwell. Irradiations were performed in three rigs operating at irradiation temperatures between 353 and 673 K. An important feature of the experimental programme was the capability to perform repeat length measurements on individual growth specimens at intervals during their irradiation programme. This facility has allowed accurate monitoring of the growth phenomenon and changes in growth behaviour induced by the combined effects of irradiation temperature and accumulated fast neutron dose over large dose ranges. This paper reviews the main experimental results from this programme and discusses them in terms of current understanding of the growth process. Thus, it has been observed that, in annealed Zircaloy-2 at temperatures between 553 and 673 K, a transition from saturating growth to accelerating growth rates occurs with increasing dose. The dose above which this "growth breakaway" takes place is seen to be inversely dependent on irradiation temperature in mis temperature range. The well-documented difference in growth behaviour between annealed and cold-worked Zircaloy-2 observed at relatively low irradiation temperatures, in which cold-worked material grows at a high linear rate over large dose ranges, is not observed at 673 K. Comparison is made with reported results on similar material irradiated in other irradiation facilities. The growth data are interpreted in terms of recent theories regarding the development during fast neutron irradiation of a cold-worked microstructure consisting of < a>- and < c>-type dislocations. Irradiation growth behaviour of annealed polycrystalline iodide zirconium between 353 and 673 K contrasts strongly with that in annealed Zircaloy-2 with low irradiation growth rates being observed over a large dose and temperature range. The influence of key irradiation parameters on the growth process have been examined in a series of studies initiated as part of a collaborative programme with AECL Chalk River Nuclear Labs. Final results from the studies on annealed and deformed single-crystal zirconium are reported here. They show that growth saturates rapidly at low dose in annealed single-crystal material irradiated at 353 and 553 K but that a gradual increase in growth strain is observed on irradiation to high dose at 553 K. Single-crystal specimens heavily swaged prior to irradiation at 353 K and given different pre-irradiation heat-treatments exhibit high near-linear or accelerating growth rates. These growth data are interpreted in terms of the importance of grain boundaries and twin boundaries as sinks for point defects which allow point defect separation and hence growth to continue to high dose. Finally, the results of growth experiments performed on Zr-0.1% Sn and Zr-1.5% Sn alloys at 353 and 553 K are reviewed. These experiments confirm the important role played by alloying additions and impurities on the growth process in zirconium and Zircaloy-2.

  7. Irradiation exposure modulates central opioid functions

    SciTech Connect

    Dougherty, P.M.; Dafny, N.

    1987-11-01

    Exposure to low doses of gamma irradiation results in the modification of both the antinociceptive properties of morphine and the severity of naloxone-precipitated withdrawal in morphine-dependent rats. To better define the interactions between gamma irradiation and these opiate-mediated phenomena, dose-response studies were undertaken of the effect of irradiation on morphine-induced antinociception, and on the naloxone-precipitated withdrawal syndrome of morphine-dependent rats. In addition, electrophysiologic studies were conducted in rats after irradiation exposure and morphine treatment correlating with the behavioral studies. The observations obtained demonstrated that the antinociceptive effects of morphine as well as naloxone-precipitated withdrawal were modified in a dose-dependent manner by irradiation exposure. In addition, irradiation-induced changes in the evoked responses obtained from four different brain regions demonstrated transient alterations in both baseline and morphine-treated responses that may reflect the alterations observed in the behavioral paradigms. These results suggest that the effects of irradiation on opiate activities resulted from physiologic alterations of central endogenous opioid systems due to alterations manifested within peripheral targets.

  8. Rheological changes in irradiated chicken eggs

    NASA Astrophysics Data System (ADS)

    Ferreira, Lúcia F. S.; Del Mastro, Nélida L.

    1998-06-01

    Pathogenic bacteria may cause foodborne illnesses. Humans may introduce pathogens into foods during production, processing, distribution and or preparation. Some of these microorganisms are able to survive conventional preservation treatments. Heat pasteurization, which is a well established and satisfactory means of decontamination/disinfection of liquid foods, cannot efficiently achieve a similar objective for solid foods. Extensive work carried out worldwide has shown that irradiation is efficient in eradicating foodborne pathogens like Salmonella spp. that can contaminate poultry products. In this work Co-60 gamma irradiation was applied to samples of industrial powder white, yolk and whole egg at doses between 0 and 25 kGy. Samples were rehydrated and the viscosity measured in a Brookfield viscosimeter, model DV III at 5, 15 and 25°C. The rheological behaviour among the various kinds of samples were markedly different. Irradiation with doses up to 5 kGy, known to reduced bacterial contamination to non-detectable levels, showed almost no variation of viscosity of irradiated egg white samples. On the other hand, whole or yolk egg samples showed some changes in rheological properties depending on the dose level, showing the predominance of whether polimerization or degradation as a result of the irradiation. Additionally, irradiation of yolk egg powder reduced yolk color as a function of the irradiation exposure implemented. The importance of these results are discussed in terms of possible industrial applications.

  9. Influence of microwave irradiation on enzyme kinetics

    NASA Astrophysics Data System (ADS)

    Pavelki?, V. M.; Stanisavljev, D. R.; Gop?evi?, K. R.; Beljanski, M. V.

    2009-09-01

    The in vitro effect of 2.45 GHz microwave irradiation on porcine pepsin activity under controlled temperature and absorbed microwave power via kinetic parameters was evaluated. Kinetic study with respect of time of irradiation demonstrated the existence of an inactivation effect of microwaves at pH 2 on pepsin molecule. Bovine serum albumin (BSA)-bromphenol blue (BPB) complex was used as substrate for the assay of pepsin by kinetic method. Depending on absorbed microwave dose, the degree of caused inactivation varies from 39.11 to 45.91% for 5 and 20 min of pepsin MW irradiation, respectively. The V maxapp and K mapp were calculated for low (5 min of MW irradiation) and higher specific absorbed dose (20 min of MW irradiation), as well as for untreated enzyme, from double reciprocal Lineweaver-Burk plot. The effect of microwaves on substrate (BSA-BPB complex) was also investigated. For reaction performed with MW irradiated substrate for 5 min the reaction rate was decreased for 15.15%, while for 20 min of substrate irradiation reaction rate was decreased for 25.52% compared to the control reaction.

  10. Reconstruction of solar UV irradiance since 1974

    NASA Astrophysics Data System (ADS)

    Krivova, N. A.; Solanki, S. K.; Wenzler, T.; Podlipnik, B.

    2009-09-01

    Variations of the solar UV irradiance are an important driver of chemical and physical processes in the Earth's upper atmosphere and may also influence global climate. Here we reconstruct solar UV irradiance in the range 115-400 nm over the period 1974-2007 by making use of the recently developed empirical extension of the Spectral And Total Irradiance Reconstruction (SATIRE) models employing Solar Ultraviolet Spectral Irradiance Monitor (SUSIM) data. The evolution of the solar photospheric magnetic flux, which is a central input to the model, is described by the magnetograms and continuum images recorded at the Kitt Peak National Solar Observatory between 1974 and 2003 and by the Michelson Doppler Imager instrument on SOHO since 1996. The reconstruction extends the available observational record by 1.5 solar cycles. The reconstructed Ly-? irradiance agrees well with the composite time series by Woods et al. (2000). The amplitude of the irradiance variations grows with decreasing wavelength and in the wavelength regions of special interest for studies of the Earth's climate (Ly-? and oxygen absorption continuum and bands between 130 and 350 nm) is 1-2 orders of magnitude stronger than in the visible or if integrated over all wavelengths (total solar irradiance).

  11. Dental Implants Installed in Irradiated Jaws

    PubMed Central

    Chambrone, L.; Mandia, J.; Shibli, J.A.; Romito, G.A.; Abrahao, M.

    2013-01-01

    The aim of this study was to assess the survival rate of titanium implants placed in irradiated jaws. MEDLINE, EMBASE, and CENTRAL were searched for studies assessing implants that had been placed in nongrafted sites of irradiated patients. Random effects meta-analyses assessed implant loss in irradiated versus nonirradiated patients and in irradiated patients treated with hyperbaric oxygen (HBO) therapy. Of 1,051 potentially eligible publications, 15 were included. A total of 10,150 implants were assessed in the included studies, and of these, 1,689 (14.3%) had been placed in irradiated jaws. The mean survival rate in the studies ranged from 46.3% to 98.0%. The pooled estimates indicated a significant increase in the risk of implant failure in irradiated patients (risk ratio: 2.74; 95% confidence interval: 1.86, 4.05; p < .00001) and in maxillary sites (risk ratio: 5.96; 95% confidence interval: 2.71, 13.12; p < .00001). Conversely, HBO therapy did not reduce the risk of implant failure (risk ratio: 1.28; 95% confidence interval: 0.19, 8.82; p = .80). Radiotherapy was linked to higher implant failure in the maxilla, and HBO therapy did not improve implant survival. Most included publications reported data on machined implants, and only 3 studies on HBO therapy were included. Overall, implant therapy appears to be a viable treatment option for reestablishing adequate occlusion and masticatory conditions in irradiated patients. PMID:24158336

  12. [Near infrared light irradiator using halogen lamp].

    PubMed

    Ide, Yasuo

    2012-07-01

    The practical electric light bulb was invented by Thomas Alva Edison in 1879. Halogen lamp is the toughest and brightest electric light bulb. With light filter, it is used as a source of near infrared light. Super Lizer and Alphabeam are made as near infrared light irradiator using halogen lamp. The light emmited by Super Lizer is linear polarized near infrared light. The wave length is from 600 to 1,600 nm and strongest at about 1,000 nm. Concerning Super Lizer, there is evidence of analgesic effects and normalization of the sympathetic nervous system. Super Lizer has four types of probes. SG type is used for stellate ganglion irradiation. B type is used for narrow area irradiation. C and D types are for broad area irradiation. The output of Alphabeam is not polarized. The wave length is from 700 to 1,600 nm and the strongest length is about 1,000nm. Standard attachment is used for spot irradiation. Small attachment is used for stellate ganglion irradiation. Wide attachment is used for broad area irradiation. The effects of Alphabeam are thought to be similar to that of Super Lizer. PMID:22860296

  13. Influence of irradiation on stored platelets

    SciTech Connect

    Moroff, G.; George, V.M.; Siegl, A.M.; Luban, N.L.

    1986-09-01

    Platelet concentrates intended for transfusion to immunosuppressed patients are irradiated to minimize transfusion-induced graft-versus-host disease. Because few reports describe how irradiation influences stored platelets, the authors studied whether 5000 rad of gamma irradiation, the maximum dose currently used clinically, altered platelets in vitro. Platelet concentrates were stored for either 1 day or 5 days in plastic (PL 732) containers before gamma irradiation. One unit of a pair of identical platelet concentrates was irradiated; the second unit served as a control. Irradiation did not alter platelet morphology, mean platelet volume, expression of platelet-factor-3 activity, response to hypotonic stress, extent of discharge of lactate dehydrogenase, release of beta-thromboglobulin, formation of thromboxane B2, nor the ability to undergo synergistic aggregation. The lack of any substantial change was observed whether the platelet concentrates were stored initially for either 1 day or 5 days. These results suggest that stored platelets are not altered deleteriously by irradiation with 5000 rad.

  14. Rapid detection of irradiated frozen hamburgers

    NASA Astrophysics Data System (ADS)

    Delincée, Henry

    2002-03-01

    DNA comet assay can be employed as a rapid and inexpensive screening test to check whether frozen ground beef patties (hamburgers) have been irradiated as a means to increase their safety by eliminating pathogenic bacteria, e.g. E. coli O157:H7. Such a detection procedure will provide an additional check on compliance with existing regulations, e.g. enforcement of labelling and rules in international trade. Frozen ready prepared hamburgers from the market place were `electron irradiated' with doses of 0, 1.3, 2.7, 4.5 and 7.2kGy covering the range of potential commercial irradiation. DNA fragmentation in the hamburgers was made visible within a few hours using the comet assay, and non-irradiated hamburgers could be easily discerned from the irradiated ones. Even after 9 months of frozen storage, irradiated hamburgers could be identified. Since DNA fragmentation may also occur with other food processes (e.g. temperature abuse), positive screening tests shall be confirmed using a validated method to specifically prove an irradiation treatment, e.g. EN 1784 or EN 1785.

  15. AGC-1 Post Irradiation Examination Status

    SciTech Connect

    David Swank

    2011-09-01

    The Next Generation Nuclear Plant (NGNP) Graphite R&D program is currently measuring irradiated material property changes in several grades of nuclear graphite for predicting their behavior and operating performance within the core of new Very High Temperature Reactor (VHTR) designs. The Advanced Graphite Creep (AGC) experiment consisting of six irradiation capsules will generate this irradiated graphite performance data for NGNP reactor operating conditions. All six AGC capsules in the experiment will be irradiated in the Advanced Test Reactor (ATR), disassembled in the Hot Fuel Examination Facility (HFEF), and examined at the INL Research Center (IRC) or Oak Ridge National Laboratory (ORNL). This is the first in a series of status reports on the progress of the AGC experiment. As the first capsule, AGC1 was irradiated from September 2009 to January 2011 to a maximum dose level of 6-7 dpa. The capsule was removed from ATR and transferred to the HFEF in April 2011 where the capsule was disassembled and test specimens extracted from the capsules. The first irradiated samples from AGC1 were shipped to the IRC in July 2011and initial post irradiation examination (PIE) activities were begun on the first 37 samples received. PIE activities continue for the remainder of the AGC1 specimen as they are received at the IRC.

  16. RERTR-12 Insertion 2 Irradiation Summary Report

    SciTech Connect

    D. M. Perez; G. S. Chang; D. M. Wachs; G. A. Roth; N. E. Woolstenhulme

    2012-09-01

    The Reduced Enrichment for Research and Test Reactor (RERTR) experiment RERTR-12 was designed to provide comprehensive information on the performance of uranium-molybdenum (U-Mo) based monolithic fuels for research reactor applications.1 RERTR-12 insertion 2 includes the capsules irradiated during the last three irradiation cycles. These capsules include Z, Y1, Y2 and Y3 type capsules. The following report summarizes the life of the RERTR-12 insertion 2 experiment through end of irradiation, including as-run neutronic analysis results, thermal analysis results and hydraulic testing results.

  17. Irradiation Is it Consumer-Friendly?

    NSDL National Science Digital Library

    Swamy Anantheswaran

    2000-01-01

    “Leo Altamari,” CEO of Kutztown Meat Packing Corporation, has just come back from his Monday morning staff meeting, where the major agenda item was a discussion about the irradiation of meat products.  Leo must decide whether his company should pursue meat irradiation, weighing the expense of the technology and the wariness of many consumers, even though research has shown it to be an effective means of eliminating E. coli contamination in meat products.  Developed for an introductory food science course, the case introduces students to consumer perceptions and beliefs about food irradiation and teaches them how the food industry evaluates new processing technologies from a business perspective.

  18. Effects of irradiation on grafted skin

    SciTech Connect

    Sumi, Y.; Ueda, M.; Kaneda, T.; Eto, K.

    1983-09-01

    The reaction of grafted skin to irradiation was studied in the rat and the optimum time for irradiation postoperatively was determined. There was a close correlation between the radiosensitivity and the vascularity of the graft and its recipient bed. Grafts showed different reactions depending on the time of irradiation after grafting. Those in the early hypovascular stage showed reactions similar to those of normal control skin. Severe reactions were observed in the hypervascular stage. Grafts in the late hypovascular stage showed more moderate reactions.

  19. Total body calcium analysis. [neutron irradiation

    NASA Technical Reports Server (NTRS)

    Lewellen, T. K.; Nelp, W. B.

    1974-01-01

    A technique to quantitate total body calcium in humans is developed. Total body neutron irradiation is utilized to produce argon 37. The radio argon, which diffuses into the blood stream and is excreted through the lungs, is recovered from the exhaled breath and counted inside a proportional detector. Emphasis is placed on: (1) measurement of the rate of excretion of radio argon following total body neutron irradiation; (2) the development of the radio argon collection, purification, and counting systems; and (3) development of a patient irradiation facility using a 14 MeV neutron generator. Results and applications are discussed in detail.

  20. Pulsed ion irradiated microstructures in molybdenum

    NASA Astrophysics Data System (ADS)

    Brimhall, J. L.; Simonen, E. P.; Charlot, L. A.

    1984-05-01

    Pulsed irradiation of molybdenum in the temperature range from 1025-1225 K primarily retarded void nucleation. The reduction in nucleation rate could be attributed to a throttling effect caused by annealing out of subcritical void embryos. The more rapid development of the dislocation microstructure during pulsing also contributed to a reduction in void nucleation rate. Once nucleation was complete, microstructural development was not affected by pulsed irradiation compared to steady irradiation. Little pulsing effect on total void swelling or swelling rate was observed. A proposed increase in swelling caused by disintegration of depleted zones during pulsed annealing periods was not observed.

  1. Measuring Degradation Rates Without Irradiance Data

    SciTech Connect

    Pulver, S.; Cormode, D.; Cronin, A.; Jordan, D.; Kurtz, S.; Smith, R.

    2011-02-01

    A method to report PV system degradation rates without using irradiance data is demonstrated. First, a set of relative degradation rates are determined by comparing daily AC final yields from a group of PV systems relative to the average final yield of all the PV systems. Then, the difference between relative and absolute degradation rates is found from a statistical analysis. This approach is verified by comparing to methods that utilize irradiance data. This approach is significant because PV systems are often deployed without irradiance sensors, so the analysis method described here may enable measurements of degradation using data that were previously thought to be unsuitable for degradation studies.

  2. The studies of irradiation assisted stress corrosion cracking on reactor internals stainless steel under Xe irradiation

    NASA Astrophysics Data System (ADS)

    Wang, Rong-shan; Xu, Chao-liang; Liu, Xiang-bing; Huang, Ping; Chen, Yu

    2015-02-01

    Specimens of Chinese domestic reactor internals stainless steel were irradiated with 6 MeV Xe ions for three peak displacement damage of 2, 7 and 15 dpa at room temperature. The slow strain rate tests (SSRT), grazing incidence X-ray diffraction (GIXRD) and nano-indentation tests were carried out to study the IASCC properties, phase transition and nano-hardness variations. The SSRT results indicate that the IASCC susceptibility increases with irradiation damage. Ion irradiation accelerates the stress corrosion cracking (SCC). A new ferrite phase diffraction peak of ?(1 1 0) after irradiated to 7 dpa and another two ? phase of ?(2 0 0) and ?(2 1 1) after irradiated to 15 dpa were observed by GIXRD, which may be due to localized deformation. A similar trend of irradiation hardening and IASCC susceptibility was observed, which suggests an essential connection between them.

  3. Surface Irradiances Consistent With CERES-Derived Top-of-Atmosphere Shortwave and Longwave Irradiances

    NASA Technical Reports Server (NTRS)

    Kato, Seiji; Loeb, Norman G.; Rose, Fred G.; Doelling, David R.; Rutan, David A.; Caldwell, Thomas E.; Yu, Lisan; Weller, Robert A.

    2013-01-01

    The estimate of surface irradiance on a global scale is possible through radiative transfer calculations using satellite-retrieved surface, cloud, and aerosol properties as input. Computed top-of-atmosphere (TOA) irradiances, however, do not necessarily agree with observation-based values, for example, from the Clouds and the Earth's Radiant Energy System (CERES). This paper presents amethod to determine surface irradiances using observational constraints of TOA irradiance from CERES. A Lagrange multiplier procedure is used to objectively adjust inputs based on their uncertainties such that the computed TOA irradiance is consistent with CERES-derived irradiance to within the uncertainty. These input adjustments are then used to determine surface irradiance adjustments. Observations by the Atmospheric Infrared Sounder (AIRS), Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observations (CALIPSO), CloudSat, andModerate Resolution Imaging Spectroradiometer (MODIS) that are a part of the NASA A-Train constellation provide the uncertainty estimates. A comparison with surface observations from a number of sites shows that the bias [root-mean-square (RMS) difference] between computed and observed monthlymean irradiances calculated with 10 years of data is 4.7 (13.3) W/sq m for downward shortwave and 22.5 (7.1) W/sq m for downward longwave irradiances over ocean and 21.7 (7.8) W m22 for downward shortwave and 21.0 (7.6) W/sq m for downward longwave irradiances over land. The bias andRMS error for the downward longwave and shortwave irradiances over ocean are decreased from those without constraint. Similarly, the bias and RMS error for downward longwave over land improves, although the constraint does not improve downward shortwave over land. This study demonstrates how synergetic use of multiple instruments (CERES,MODIS, CALIPSO, CloudSat, AIRS, and geostationary satellites) improves the accuracy of surface irradiance computations.

  4. Electron beam irradiation for structuring of molecular assemblies

    Microsoft Academic Search

    Victor Erokhin; Tatiana Berzina; M. P. Fontana

    2004-01-01

    Nontraditional applications of electron beam irradiation for patterning of molecular assemblies are considered. The electron beam can have the following effects on molecular layers: destruction of molecular structure under e-beam irradiation with a successive formation of new molecular system when the irradiation is stopped; variation of the properties of the layer after e-beam irradiation; crosslinking of molecules in the layer

  5. Large Animal Irradiation J. Daniel Bourland, PhD

    E-print Network

    : Total Body Irradiation dose escalation study · 15 animals, matched by sex, weight · Animal handling on randomization (depending on study design) #12;Total Body Irradiation Geometry table subject 120 cm 6 MV x ray, matched by sex, weight · Animal handling and irradiation logistics ­ After-hours irradiations · Whole body

  6. A review of the safety of cold pasteurization through irradiation

    Microsoft Academic Search

    Lester M. Crawford; Eric H. Ruff

    1996-01-01

    Perhaps no food process has been researched and reviewed more than food irradiation. The scientific basis and mechanisms of food irradiation are as thoroughly understood by the scientific community and regulatory agencies as traditional food processes. While irradiation provides many benefits, it cannot replace proper food handling as the single most critical food safety measure. Irradiation does not prevent contamination

  7. Plant improvement In vitro pollen tube division of irradiated

    E-print Network

    Boyer, Edmond

    Plant improvement In vitro pollen tube division of irradiated and non-irradiated apple pollen MP) Summary — Apple pollen irradiated at 200 and 500 Gy, used to induce haploidy by parthenogenesis, was sown in liq- uid medium to study pollen tube germination and division. Although the irradiated pollen

  8. Thermoluminescence properties of irradiated chickpea and corn

    NASA Astrophysics Data System (ADS)

    Necmeddin Yazici, A.; Bedir, Metin; Bozkurt, Halil; Bozkurt, Hüseyin

    2008-02-01

    A study was carried out to establish a detection method for irradiated chickpea and corn by thermoluminescence (TL) method. The leguminous were packed in polyethylene bags and then the packets were irradiated at room temperature at different doses by 60Co gamma source at 1, 4, 8 and 10 kGy. Minerals extracted from the leguminous were deposited onto a clean aluminum disc and TL intensities of the minerals were measured by TL. It was observed that the extracted samples from both leguminous exhibit good TL Intensity and the TL intensity of glow curves of them increased proportionally to irradiation doses. The TL glow curve of both irradiated leguminous presents a single broad peak below 400 °C. The TL trapping parameters glow peaks were estimated by the additive dose (AD), Tm( Ea)- Tstop and computerized glow curve deconvolution (CGCD) methods. The fading characteristics of glow curves were also recorded up to 6 months.

  9. Argon laser irradiation of the otolithic organ

    SciTech Connect

    Okuno, T.; Nomura, Y.; Young, Y.H.; Hara, M. (Univ. of Tokyo (Japan))

    1990-12-01

    An argon laser was used to irradiate the otolithic organs of guinea pigs and cynomolgus monkeys. After stapedectomy, the argon laser (1.5 W x 0.5 sec/shot) irradiated the utricle or saccule without touching the sensory organs. The stapes was replaced over the oval window after irradiation. The animals used for acute observation were killed immediately for morphologic studies; those used for long-term observation were kept alive for 2, 4, or 10 weeks. Acute observation revealed that sensory and supporting cells were elevated from the basement membrane only in the irradiated area. No rupture of the membranous labyrinth was observed. Long-term observation revealed that the otolith of the macula utriculi had disappeared in 2-week specimens. The entire macula utricili had disappeared in 10-week specimens. No morphologic changes were observed in cochlea, semicircular canals, or membranous labyrinth. The saccule showed similar changes.

  10. Hydrogen trapping in neutron-irradiated graphite

    NASA Astrophysics Data System (ADS)

    Atsumi, H.; Muhaimin, A.; Tanabe, T.; Shikama, T.

    2009-04-01

    Bulk hydrogen retention and the analysis of absorption kinetics have been studied on three brands of graphite irradiated with neutrons at various fluences. Two kinds of hydrogen trapping sites may exist and be additionally produced during irradiation: interstitial cluster loop edge sites (trap 1) and carbon dangling bonds at edge surfaces of crystallites (trap 2). Neutron irradiation preferably creates trap 2 sites at lower fluences and trap 1 sites at a higher fluence above 0.017 dpa. Trap 2 tends to be annealed out at high temperatures, although trap 1 is hardly decreased even at 1873 K. Diffusion coefficients of hydrogen are reduced for 1-2 orders of magnitude after neutron irradiation at 0.047 dpa, although the activation energy of hydrogen diffusion is kept nearly the same level to unirradiated samples.

  11. UV microspot irradiator at Columbia University.

    PubMed

    Bigelow, Alan W; Ponnaiya, Brian; Targoff, Kimara L; Brenner, David J

    2013-08-01

    The Radiological Research Accelerator Facility at Columbia University has recently added a UV microspot irradiator to a microbeam irradiation platform. This UV microspot irradiator applies multiphoton excitation at the focal point of an incident laser as the source for cell damage, and with this approach, a single cell within a 3D sample can be targeted and exposed to damaging UV. The UV microspot's ability to impart cellular damage within 3D is an advantage over all other microbeam techniques, which instead impart damage to numerous cells along microbeam tracks. This short communication is an overview, and a description of the UV microspot including the following applications and demonstrations of selective damage to live single cell targets: DNA damage foci formation, patterned irradiation, photoactivation, targeting of mitochondria, and targeting of individual cardiomyocytes in a live zebrafish embryo. PMID:23708525

  12. Food Irradiation: Is It Safe and Wholesome?

    ERIC Educational Resources Information Center

    Rebus, Shirley

    1990-01-01

    Addresses some of the major issues of food irradiation with respect to safety and wholesomeness, including formation of radiolytic products, effects on nutrients, prevention of food-borne illness, development of radiation-resistant bacteria, and formation of afaltoxins. (Author)

  13. Selective irradiation of the vascular endothelium

    E-print Network

    Schuller, Bradley W

    2007-01-01

    We developed a unique methodology to selectively irradiate the vascular endothelium in vivo to better understand the role of vascular damage in causing normal tissue radiation side-effects.The relationship between vascular ...

  14. EFFECT OF DIETHYLHYDROXYLAMINE ON SMOG CHAMBER IRRADIATIONS

    EPA Science Inventory

    The addition of diethylhydroxylamine (DEHA) to the urban atmosphere had been suggested as a means of preventing photochemical smog. Smog chamber studies were carried out to investigate the photochemical smog formation characteristics of irradiated hydrocarbon-nitrogen oxides - DE...

  15. Degradation pathways of PCB upon gamma irradiation

    SciTech Connect

    Lepine, F. (Institut Armand-Frappier, Laval, Quebec (Canada)); Masse, R. (Institut National de la Recherche Scientifique, Pointe-Claire, Quebec (Canada))

    1990-11-01

    In order to understand the modifications of the chromatographic profile of Aroclor 1260 upon gamma irradiation, a total of 14 pure polychlorinated biphenyl (PCB) congeners were separately irradiated in solution. Dechlorination was observed, and the generated products were investigated by gas chromatography and mass spectrometry. Degradation proceeds more rapidly in methanol/water mixture than in petroleum ether, but the relative amount of ortho-dechlorinated congeners formed upon irradiation was smaller in the former solvent Ortho chlorines are preferentially lost in petroleum ether except when they are involved in a 2,5 (or 3,6) substitution pattern, in which case para dechlorination becomes predominant. The precursors of some toxicologically important congeners such as congeners 77, 118, 167, and 189 have been identified. These data are useful to rationalize the modifications of the chromatographic profile of PCB complex mixture upon gamma irradiation.

  16. 10 CFR 36.33 - Irradiator pools.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ...pool water level is below the normal low water level or above the normal high water level. (e) Irradiator pools must be equipped with a purification system designed to be capable of maintaining the water during normal operation at a...

  17. 10 CFR 36.33 - Irradiator pools.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ...pool water level is below the normal low water level or above the normal high water level. (e) Irradiator pools must be equipped with a purification system designed to be capable of maintaining the water during normal operation at a...

  18. 10 CFR 36.33 - Irradiator pools.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ...pool water level is below the normal low water level or above the normal high water level. (e) Irradiator pools must be equipped with a purification system designed to be capable of maintaining the water during normal operation at a...

  19. 10 CFR 36.33 - Irradiator pools.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ...pool water level is below the normal low water level or above the normal high water level. (e) Irradiator pools must be equipped with a purification system designed to be capable of maintaining the water during normal operation at a...

  20. Degradation of monochlorophenols by ?-irradiation

    NASA Astrophysics Data System (ADS)

    Schmid, S.; Krajnik, P.; Quint, R. M.; Solar, S.

    1997-11-01

    The degradation of aqueous 5 × 10 -4 mol dm -3 2-, 3- and 4-chlorophenol (2-CIP, 3-CIP, 4-CIP) under reducing and oxidizing conditions has been studied by steady state ?-radiolysis. The reaction with e aq- leads to reductive dechlorination which equals the degradation of the chlorophenols. Solely phenol is the major organic compound formed. In N 2O saturated solutions the dehalogenation is much less effective. In the case of 4-CIP 40% and in that of 2- and 3-CIP only 20% of the decomposed substrates are resulting in chlorine free organic compounds. From these pyrocatechol for 2-CIP and hydroquinone for 4-CIP could be identified in minor amounts. Main products are the hydroxylated substrates originating from the primarily formed ortho- and para OH-adducts. These are for 2-CIP: chlorohydroquinone and 3-chlorocatechol, for 3-CIP: chlorohydroquinone, 3- and 4-chlorocatechol and for 4-CIP: 4-chlorocatechol. In the presence of oxygen, where the OH-adducts are converted into peroxyl radicals, the degradation yield of the substrates corresponds to that of OH radicals up to doses of 0.5 kGy. The dechlorination process in this dose range is 50% for 4-CIP, and 33% for 2- and 3-CIP. The position of chlorine on the aromatic ring strongly influences the dehalogenation and degradation process. A pronounced dependency of the dose/yield curves on the oxygen concentration was observed. This indicates that for an efficient degradation process of chlorophenols oxygen supply is necessary during irradiation.

  1. Unilateral lung hyperlucency after mediastinal irradiation

    SciTech Connect

    Wencel, M.L.; Sitrin, R.G.

    1988-04-01

    A 39-yr-old woman developed progressive exertional dyspnea 13 yr after receiving mediastinal irradiation for Hodgkin's disease. Chest roentgenogram showed a hyperlucent right lung. Pulmonary blood flow was markedly reduced on the right by ventilation-perfusion scanning. Pulmonary angiography showed attenuation and diffuse atrophy of the right pulmonary artery and its branches. This case represents a late and uncommon complication of mediastinal irradiation manifesting as a unilateral hyperlucent lung.

  2. Radiolytic characteristics of nitrite by gamma irradiation

    Microsoft Academic Search

    Hyun-Joo Ahn; Jae-Hyun Kim; Cheorun Jo; Hong-Sun Yook; Myung-Woo Byun

    2003-01-01

    The characteristics of nitrite radiolysis by gamma rays were investigated. Sodium nitrite in deionized distilled water was irradiated at 0, 5, 10, 15, 20, 25, 30 and 40 kGy, and the degradation rate constant was calculated. The sodium nitrite was significantly reduced by irradiation in a dose-dependent manner (P<0.05). The degradation rate of sodium nitrite fitted a first-order model; a

  3. COBALT60 Gamma Irradiation of Shrimp

    Microsoft Academic Search

    Nancy L. B. Sullivan; N. L. B

    1993-01-01

    Meta- and ortho-tyrosine were measured using high performance liquid chromatography (HPLC) in conjunction with electrochemical detection in shrimp irradiated using cobalt-60 gamma radiation in the absorbed dose range 0.8 to 6.0 kGy, in nonirradiated shrimp, and in bovine serum albumin (BSA) irradiated in dilute aqueous solution at 25.0 kGy. Ortho-tyrosine was measured in nonirradiated BSA. Para-, meta-, and ortho-tyrosine were

  4. Gamma irradiation effects in W films

    SciTech Connect

    Claro, Luiz H. [Instituto de Estudos Avancados - IEAv, Rod. dos Tamoios, km 5,5, CEP: 12228-840, Sao Jose dos Campos, SP (Brazil) and Faculdade de Tecnologia Sao Francisco - FATESF, Av. Siqueira Campos, 1174, CEP: 12207-000, Jacarei (Brazil); Santos, Ingrid A. [Instituto de Estudos Avancados - IEAv, Rod. dos Tamoios, km 5,5, CEP: 12228-840, Sao Jose dos Campos, SP (Brazil); Silva, Cassia F. [Faculdade de Tecnologia Sao Francisco - FATESF, Av. Siqueira Campos, 1174, CEP: 12207-000, Jacarei, SP (Brazil)

    2013-05-06

    Using the van Der Pauw methodology, the surface resistivity of irradiated tungsten films deposited on Silicon substrate was measured. The films were exposed to {gamma} radiation using a isotopic {sup 60}Co source in three irradiation stages attaining 40.35 kGy in total dose. The obtained results for superficial resistivity display a time annealing features and their values are proportional to the total dose.

  5. Blue irradiance intercomparison in the medical field

    NASA Astrophysics Data System (ADS)

    Ferreira, Antonio F. G.

    2012-10-01

    This work presents the results of a blue irradiance intercomparison among industrial laboratories of medical devices companies. This intercomparison aims to support the metrological issues of medical equipment manufactures regarding the blue irradiance infant phototherapy equipment requirements on the international standard IEC 60601-2-50:2000. The results showed a low agreement of participants' measurements according to normalized error criterion. The major explanation for this result is associated to an incorrect equipment choice and long recalibration period.

  6. Thermoluminscence of irradiated herbs and spices

    NASA Astrophysics Data System (ADS)

    Mamoon, A.; Abdul-Fattah, A. A.; Abulfaraj, W. H.

    1994-07-01

    Several types of herbs and spices from the local market were irradiated with different doses of ? radiations. Doses varied from a few kilograys to 10 kilograys. Thermoluminescence of the irradiated samples and their controls was investigated. For the same type of herb or spice glow curves of different magnitudes, corresponding somewhat to the doses given, were obtained from the irradiated samples. Most control samples gave little or insignificant glow. Glow curves from different herbs and spices irradiated with the same doses were not similar in the strength of the glow signal given. Samples of the black pepper obtained from different packages sometimes give glow curves of very different intensities. Samples from irradiated black pepper were found to show little fading of their glow curves even at 9 months postirradiation. All irradiations were done under the same experimental conditions and at a dose rate of approximately 1 kGy h-1. The glow curves were obtained using a heating rate of about 9°C s-1 and a constant nitrogen flow rate.

  7. The effects of irradiation on blood components

    SciTech Connect

    Button, L.N.; DeWolf, W.C.; Newburger, P.E.; Jacobson, M.S.; Kevy, S.V.

    1981-01-01

    The functional properties of formed elements of whole blood were studied following irradiation doses of 500 to 20,000 rads. Irradiated lymphocytes retained only 1.5 per cent of their 3H thymidine uptake after a 5,000-rad exposure and none after 7,500 rads. Red blood cells stored for 21 days and then irradiated with 5,000 rads had the same survival as nonirradiated controls. In contrast, 5,000 rads reduced platelet yields. However, transfused irradiated platelets produced the expected increases in platelet counts and controlled hemostasis in thrombocytopenic patients. After 5,000 rads, granulocytes had normal bacterial killing capacity, chemotactic mobility, and normal superoxide production after high-dose stimulation. Nitroblue tetrazolium reduction and ingestion stimulated by complement opsonized oil droplets were not diminished by 5,000- and 10,000-rad irradiation. The functional qualities of cellular blood components other than lymphocytes are not compromised by 5,000 rads. This irradiation dose may be an effective means of controlling incidence of graft-vs-host disease in immunosuppressed patients.

  8. Wettability inversion induced by weak electron irradiation

    SciTech Connect

    Aronov, Daniel; Molotskii, Michel [Department of Physical Electronics, School of Electrical Engineering, Tel Aviv University, Tel Aviv 69978 (Israel)

    2008-12-01

    We investigate a wettability modification of ultrathin dielectric films induced by an electron irradiation. The effect of wettability inversion, transition from hydrophobic to hydrophilic state, is predicted for low irradiation doses. It is supposed that the inversion is caused by a change in the basic mechanism of the influence of an electron irradiation on the interface free energy. For high irradiation doses, the effect of the decrease in wettability under electron irradiation is caused by the interactions of an excess charge in the film with its image charges. At low doses, the mechanism is referred to the interaction of surface charges, which function as hydrophilic adsorption centers, with water molecules. The predicted effect of the wettability inversion has been experimentally verified with electron irradiation of silicon dioxide ultrathin films. A dramatic reduction in water drop surface tension on the liquid/vapor interface has been observed. Such reduction is explained by drop charging as a result of carriers tunneling from semiconductor through ultrathin oxide layer.

  9. Operating plan for capsule HRB-21 irradiation

    SciTech Connect

    Packan, N.H.; Kania, M.J.; Thoms, K.R.; Clemmer, E.D.

    1989-12-01

    Irradiation capsule HRB-21 is a test capsule designed to provide modular high-temperature gas-cooled reactor (MHTGR) coated-particle fuel-performance data under test reactor conditions representative, at the end of the irradiation, of normal MHTGR operation. The irradiated fuel will be used in postirradiation tests to validate performance models simulating specific licensing basis events. The accelerated irradiation is to take place in the High-Flux Isotope Reactor at ORNL. This report identifies the procedures to be followed in carrying out the irradiation of HRB-21. Included is a description of the capsule with emphasis on the provisions for monitoring neutron fluence and controlling the irradiation temperature. The arrangements of the sweep gas circuit and gas analysis system are discussed, because on-line detection of fission gases released from individual failed fuel particles is a critical aspect of this test. The required data and measurements are specified, both at reactor startup and at particular intervals for the duration of the experiment. Documentation and quality assurance requirements are described, and the report concludes with a tentative schedule for the HRB-21 experiment. 7 refs., 7 figs., 1 tab.

  10. Evaluation of irradiation effects on concrete structure

    SciTech Connect

    Kontani, O.; Ishizawa, A. [Kajima Corporation, Nuclear Power Dept., 6-5-11 Akasaka, Minato-ku, Tokyo, 107-8348 (Japan); Maruyama, I. [Nagoya Univ., Graduate School of Environmental Studies, Furocho, Chikusa-ku, Nagoya , 464-8603 (Japan); Takizawa, M.; Sato, O. [Mitsubishi Research Inst. Inc., Science and Safety Policy Research Div., Nuclear Energy Systems Group, 2-10-3 Nagatacho, Chiyoda-ku, Tokyo 100-8141 (Japan)

    2012-07-01

    In assessing the soundness of irradiated concrete of nuclear power plants operated for more than 30 years, reference levels are employed: 1x10{sup 20} n/cm{sup 2} for fast neutrons and 2x10{sup 10} rad (2x10{sup 5} kGy) for gamma rays. Concrete structures are regarded as sound when the estimated irradiance levels after 60 years of operation are less than the reference levels. The reference levels were obtained from a paper by Hilsdorf. It was found, however, that the test conditions in which data were obtained by the researchers referred in that paper are very different from the irradiation and heat conditions usually found in a Light Water Reactor (LWR), and therefore aren't appropriate for assessing the soundness of irradiated concrete of an LWR. This paper investigates the interactions between radiation and concrete and presents the results of gamma ray irradiation tests on cement paste samples in order to provide a better understanding of the irradiation effects on concrete. (authors)

  11. Investigation of the effect of some irradiation parameters on the response of various types of dosimeters to electron irradiation

    Microsoft Academic Search

    K. Farah; F. Kuntz; O. Kadri; L. Ghedira

    2004-01-01

    Several undyed and dyed polymer films are commercially available for dosimetry in intense radiation fields, especially for radiation processing of food and sterilisation of medical devices. The effects of temperature during irradiation and post-irradiation stability, on the response of these dosimeters are of importance to operators of irradiation facilities. The present study investigates the effects of temperature during irradiation by

  12. Investigation of the effect of some irradiation parameters on the response of various types of dosimeters to electron irradiation

    NASA Astrophysics Data System (ADS)

    Farah, K.; Kuntz, F.; Kadri, O.; Ghedira, L.

    2004-09-01

    Several undyed and dyed polymer films are commercially available for dosimetry in intense radiation fields, especially for radiation processing of food and sterilisation of medical devices. The effects of temperature during irradiation and post-irradiation stability, on the response of these dosimeters are of importance to operators of irradiation facilities. The present study investigates the effects of temperature during irradiation by 2.2 MeV electrons beam accelerator and post irradiation storage on the response of several types of dosimeter films. All dosimeters showed a significant effect of temperature during irradiation and post-irradiation storage.

  13. Étude au canon à gaz léger à deux étages des propriétés sous choc de l'alliage de fer Z2 CN18-10 et de l'alliage d'uranium UCr_5Ti_4

    NASA Astrophysics Data System (ADS)

    Lezaud, J.-M.; Chaissé, F.

    1993-02-01

    Using a two stage light gas gun, we study under shock-loading two metallic alloys behaviours. Compression and release isentrope are determined. For this purpose, impedance matching method associated with electronic time-arrival measurement is used. We note a linear relationship U(u) [shock velocity versus material velocity] for the two metallic alloys. The Griineisen parameter and sound velocity behind the shock jump are expressed versus the parameters A and B governing the relationship U(u). The experimental data are in good agreement with the analysis proposed. A l'aide d'un canon à gaz léger à deux étages, on étudie les propriétés sous choc d'un alliage de fer et d'un alliage d'uranium. La polaire de choc et l'isentrope de détente sont déterminées en utilisant la méthode d'adaptation d'impédance à laquelle est associée une chronométrie électronique. Nous notons une relation linéaire U(u) [célérité de l'onde de choc saut de vitesse matérielle] pour les deux alliages. Le coefficient de Grüneisen et la célérité du son à l'aval du choc sont exprimés en fonction des paramètres A et B de la relation U(u). Les résultats expérimentaux sont en accord avec l'analyse proposée.

  14. Comparison of Deuterium Retention for Ion-irradiated and Neutron-irradiated Tungsten

    SciTech Connect

    Yasuhisa Oya; Masashi Shimada; Makoto Kobayashi; Takuji Oda; Masanori Hara; Hideo Watanabe; Yuji Hatano; Pattrick Calderoni; Kenji Okuno

    2011-12-01

    The behavior of D retention for Fe{sup 2+}-irradiated tungsten with a damage of 0.025-3 dpa was compared with that for neutron-irradiated tungsten with 0.025 dpa. The D{sub 2} thermal desorption spectroscopy (TDS) spectra for Fe{sup 2+}-irradiated tungsten consisted of two desorption stages at 450 and 550 K, while that for neutron-irradiated tungsten was composed of three stages and an addition desorption stage was found at 750 K. The desorption rate of the major desorption stage at 550K increased as the displacement damage increased due to Fe{sup 2+} irradiation increasing. In addition, the first desorption stage at 450K was found only for damaged samples. Therefore, the second stage would be based on intrinsic defects or vacancy produced by Fe{sup 2+} irradiation, and the first stage should be the accumulation of D in mono-vacancy and the activation energy would be relatively reduced, where the dislocation loop and vacancy is produced. The third one was found only for neutron irradiation, showing the D trapping by a void or vacancy cluster, and the diffusion effect is also contributed to by the high full-width at half-maximum of the TDS spectrum. Therefore, it can be said that the D{sub 2} TDS spectra for Fe{sup 2+}-irradiated tungsten cannot represent that for the neutron-irradiated one, indicating that the deuterium trapping and desorption mechanism for neutron-irradiated tungsten is different from that for the ion-irradiated one.

  15. Quality of gamma ray-irradiated iceberg lettuce and treatments to minimize irradiation-induced disorders

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Irradiation of Iceberg lettuce was recently approved by the FDA to enhance microbial safety and to extend shelf-life at doses up to 4 kGy. However, the radiation tolerance of whole head lettuce is unclear. The present study was conducted to investigate the effects of irradiation on the quality of he...

  16. Electric properties of non-irradiated and gamma-irradiated bone

    Microsoft Academic Search

    Ewa Marzec; Leszek Kubisz

    2002-01-01

    Dielectric spectroscopy has been applied to study the effect of water and ?-irradiation on bone. Measurements were performed in the electric field frequency range of 101–105 Hz and at temperatures from 22 to 240 °C. The bone samples contained about 3% water by mass at room temperature. The doses of ?-irradiation were 5, 50, 100, 300 and 1000 kGy. The

  17. Removal of carbon-14 from irradiated graphite

    NASA Astrophysics Data System (ADS)

    Dunzik-Gougar, Mary Lou; Smith, Tara E.

    2014-08-01

    Approximately 250,000 tonnes of irradiated graphite waste exists worldwide and that quantity is expected to increase with decommissioning of Generation II reactors and deployment of Generation IV gas-cooled, graphite moderated reactors. This situation indicates the need for a graphite waste management strategy. On of the isotopes of great concern for long-term disposal of irradiated graphite is carbon-14 (14C), with a half-life of 5730 years. Study of irradiated graphite from some nuclear reactors indicates 14C is concentrated on the outer 5 mm of the graphite structure. The aim of the research presented here is to develop a practical method by which 14C can be removed. In parallel with these efforts, the same irradiated graphite material is being characterized to identify the chemical form of 14C in irradiated graphite. A nuclear-grade graphite, NBG-18, and a high-surface-area graphite foam, POCOFoam®, were exposed to liquid nitrogen (to increase the quantity of 14C precursor) and neutron-irradiated (1013 neutrons/cm2/s). During post-irradiation thermal treatment, graphite samples were heated in the presence of an inert carrier gas (with or without the addition of an oxidant gas), which carries off gaseous products released during treatment. Graphite gasification occurs via interaction with adsorbed oxygen complexes. Experiments in argon only were performed at 900 °C and 1400 °C to evaluate the selective removal of 14C. Thermal treatment also was performed with the addition of 3 and 5 vol% oxygen at temperatures 700 °C and 1400 °C. Thermal treatment experiments were evaluated for the effective selective removal of 14C. Lower temperatures and oxygen levels correlated to more efficient 14C removal.

  18. Tolerance of bile duct to intraoperative irradiation

    SciTech Connect

    Sindelar, W.F.; Tepper, J.; Travis, E.L.

    1982-09-01

    In order to determine the effects of intraoperative radiation therapy of the bile duct and surrounding tissues, seven adult dogs were subjected to laparotomy and intraoperative irradiation with 11 MeV electrons. Two animals were treated at each dose level of 2000, 3000, and 4500 rads. A single dog which received a laparotomy and sham irradiation served as a control. The irradiation field consisted of a 5 cm diameter circle encompassing the extrahepatic bile duct, portal vein, hepatic artery, and lateral duodenal wall. The animals were followed clinically for mor than 18 months after treatment, and autopsies were performed on dogs that died to assess radiation-induced complications or tissue damage. All dogs developed fibrosis and mural thickening of the common duct, which appeared by 6 weeks following irradiation and which was dose-related, being mild at low doses and more severe at high doses. Hepatic changes were seen as early as 6 weeks after irradiation, consisting of periportal inflammation and fibrosis. The hepatic changes appeared earliest at the highest doses. Frank biliary cirrhosis eventually developed at all dose levels. Duodenal fibrosis appeared in the irradiation portal, being most severe at the highest doses and in some animals resulting in duodenal obstruction. No changes were observed in irradiated portions of portal vein and hepatic artery at any dose level. It was concluded that intraoperative radiation therapy delivered to the region of the common duct leads to ductal fibrosis, partial biliary obstruction with secondary hepatic changes, and duodenal fibrosis if bowel wall is included in the field. Clinical use of intraoperative radiation therapy to the bile duct in humans may require routine use of biliary and duodenal bypass to prevent obstructive complications.

  19. The volume effect in irradiated mouse colorectum

    NASA Astrophysics Data System (ADS)

    Skwarchuk, Mark William

    1997-11-01

    Damage of the colorectum is the dose-limiting normal tissue complication following radiotherapy of prostate and cervical cancers. One approach for decreasing complications is to physically reduce the treatment volume. Mathematical models have been previously developed to describe the change in associated toxicity with a change in irradiated volume, i.e. the 'volume effect', for serial-type normal tissues including the colorectum. The first goal of this thesis was to test the hypothesis that there would not be a threshold length in the development of obstruction after irradiation of mouse colorectum, as predicted by the Probability model of the volume effect. The second goal was to examine if there were differences in the threshold and in the incidence of colorectal obstruction after irradiation of two mouse strains, C57B1/6 (C57) and C3Hf/Kam (C3H), previously found to be fibrosis-prone and-resistant, respectively, after lung irradiation due, in part, to genetic differences. The hypothesis examined was that differences in incidence between strains were due to the differential expression of the fibrogenic cytokines TGF/beta and TNF/alpha. Various lengths of C57 and C3H mouse colorectum were irradiated and the incidence of colorectal obstruction was followed up to 15 months. A threshold length was observed for both mouse strains, in contradiction of model predictions. The mechanism of the threshold was epithelial regeneration after irradiation. C57 mice had significantly higher incidence of colorectal obstruction compared to C3H mice, especially at smaller irradiated lengths. Colorectal tissue was obtained at various times after irradiation and prepared for histology, immunohistochemistry and RNase protection assay for measurement of TGF/beta 1, 2, 3 and TNF/alpha mRNA. Distinct strain differences in the histological time of appearance and spatial locations of fibrosis were observed. However, there were no consistent strain difference in mRNA levels or immunolocalization for any of the cytokines examined. The data indicate the need for volume effect models that account for biologically important processes, such as the effect of epithelial regeneration after irradiation. As well, changes in fibrogenic cytokines at the mRNA level do not contribute to the strain difference in radiation-induced colorectal obstruction.

  20. Irradiation Effects on Diagnostic Components for ITER

    NASA Astrophysics Data System (ADS)

    Nishitani, Takeo; Shikama, Tatsuo; Reichel, Roger; Sugie, Tatsuo; Kakuta, Tsunemi; Kasai, Satoshi; Ishitsuka, Etsuo; Yamamoto, Shin

    Irradiation tests on many diagnostic components have been carried out as a part of the R&D program of the ITER Engineering Design Activities (EDA). Five kinds of ITER round robin fibers were irradiated in JMTR and60Co ?-rays. Induced transmission loss of those fibers are much smaller than that of pure SiO2 core fiber. Especially, KU-H2G from Russian Federation and F-doped fibers from Japan have rather good radiation hardness even in the visible range. Those fibers might be available in the diagnostic port of ITER. The transmissivity of KU-1 quartz, which is a candidate of the window material for UV and visible spectroscopy in ITER, was measured under the irradiation of 14 MeV neutrons and ?-rays in the UV range (200 - 400 nm). Significant transmission loss was observed in the wavelength range of 200-300 nm. The Mica substrate bolometer was irradiated in JMTR during three irradiation cycles. Total neutron fluence was about 1×1024 n/m2 which was equivalent to 0.1 dpa. Significant increase in the meander resistance was observed, which was causedby the nuclear transmutation of gold into mercury. The use of gold meanders might be problematic in ITER.

  1. Carotid artery disease following external cervical irradiation

    SciTech Connect

    Elerding, S.C.; Fernandez, R.N.; Grotta, J.C.; Lindberg, R.D.; Causay, L.C.; McMurtrey, M.J.

    1981-01-01

    A retrospective study of 910 patients surviving at least five years after cervical irradiation for Hodgkin's disease, non-Hodgkin's lymphoma, or primary head an neck neoplasms showed the incidence of stroke following cervical irradiation was 63 of 910 patients (6.3%) during a mean period of observation of nine years. This represents a trend toward an increased risk for this population observed over the same period of time (p . 0.39). A prospective study of 118 similar patients currently living five years after cervical radiotherapy was performed to determine the incidence of carotid artery disease occurring as a consequence of neck irradiation. Abnormal carotid phonangiograms (CPA) were found in 25% of the patients and abnormal oculoplethysmographs (OPG) were found in 17%. These studies represent significant carotid lesions that are not expected in such a population. It is concluded that the carotid stenoses demonstrated are most likely a consequence of prior irradiation. Patients that are five-year survivors of cervical irradiation should have noninvasive vascular laboratory studies performed as part of their routine follow-up examinations in order to detect these carotid lesions while they are occult.

  2. Disinfestation of different cereal products by irradiation

    NASA Astrophysics Data System (ADS)

    Kovács, E.; Kiss, I.; Boros, A.; Horváth, Ny.; Tóth, J.; Gyulai, P.; Szalma, Á.

    The sensitivity of overlineTribolium confusum - small flour beetle - to radiation was studied in a dose range of 0-0.8 kGy. We found that the insect egg was the most sensitive to radiation, then larvae and pupae followed it. 0.2 kGy dose of irradiation kills these forms or their further development is inhibited. Imagoes do not immediately die after 0.8 kGy dose of irradiation; the young imagoes are more sensitive to radiation than the aged ones. 0.4 kGy average dose of irradiation is a suitable protection against overlineTribolium confusum. Disinfestation experiments were performed with wheat-germ and wheat-bran and parallelly the most important ingredients of the two products were analysed. The vitamin E content and the rate of lipid-oxidation of wheat germ were determined. The vitamin E content decreased after radiation treatment, however, during storage of at least 6 months, it remained at a level specified by food quality standards (higher than 10 mg%). Carbohydrate content of wheat-bran (water soluble carbohydrate content, crude-fibre and dietary fibre content) did not change at all. Storability of radiation disinfested wheat-germ was 8 months, wheat-bran 3-4 months. On the base of the results 2-2 tons of wheat-germ and wheat-bran were irradiated and trial marked in 1985. In 1986 the irradiation of 10 tons of wheat-germ is planned.

  3. Effects of irradiation on platelet function

    SciTech Connect

    Rock, G.; Adams, G.A.; Labow, R.S.

    1988-09-01

    Current medical practice involves the irradiation of blood components, including platelet concentrates, before their administration to patients with severe immunosuppression. The authors studied the effect of irradiation on in vitro platelet function and the leaching of plasticizers from the bag, both immediately and after 5 days of storage. The platelet count, white cell count, pH, glucose, lactate, platelet aggregation and release reaction, and serotonin uptake were not altered by the irradiation of random-donor or apheresis units with 2000 rads carried out at 0 and 24 hours and 5 days after collection. The leaching of di(2-ethylhexyl)phthalate from the plastic bags followed by the conversion to mono(2-ethylhexyl)phthalate was not increased by irradiation. Therefore, it is possible to irradiate platelet concentrates on the day of collection and subsequently store them for at least 5 days while maintaining in vitro function. This procedure could have considerable benefit for blood banks involved in the provision of many platelet products.

  4. Cobalt-60 gamma irradiation of shrimp

    SciTech Connect

    Sullivan, N.L.B.

    1993-01-01

    Meta- and ortho-tyrosine were measured using high performance liquid chromatography (HPLC) in conjunction with electrochemical detection in shrimp irradiated using cobalt-60 gamma radiation in the absorbed dose range 0.8 to 6.0 kGy, in nonirradiated shrimp, and in bovine serum albumin (BSA) irradiated in dilute aqueous solution at 25.0 kGy. Ortho-tyrosine was measured in nonirradiated BSA. Para-, meta-, and ortho-tyrosine was measured using HPLC in conjunction with uv-absorption detection in dilute aqueous solutions of phenylalanine irradiated in the absorbed dose range 16.0 to 195.0 kGy. The measured yields of tyrosine isomers were approximately linear as a function of absorbed dose in shrimp, and in irradiated solutions of phenylalanine up to 37.0 kGy. The occurrence of meta- and ortho-tyrosine, which had formerly been considered unique radiolytic products, has not previously been reported in nonirradiated shrimp or BSA. The conventional hydrolyzation and analytical techniques used in the present study to measure meta- and ortho-tyrosine may provide the basis for a method to detect and determine the dose used in food irradiation.

  5. The effect of gamma irradiation on injectable human amnion collagen

    SciTech Connect

    Liu, B.C.; Harrell, R.; Davis, R.H.; Dresden, M.H.; Spira, M. (Institute of Occupational Medicine, Beijing (China))

    1989-08-01

    The effect of gamma irradiation on the physicochemical properties of injectable human amnion collagen was investigated. Pepsin-extracted human amnion collagen was purified, reconstituted, and irradiated with varying doses of gamma irradiation (0.25 Mrads to 2.5 Mrads). Gamma irradiation had a significant impact on the physical characteristics of the collagen. The neutral solubility of collagen in PBS at 45{degrees}C was decreased from 100% for the nonirradiated control sample to 16% for the 2.5 Mrads irradiated sample. SDS polyacrylamide gel electrophoresis also demonstrated the dose-dependent effect of gamma irradiation on collagen cross-links. Electron microscopic observation revealed that even at low irradiation dose (0.25 Mrads), collagen fibril diameter increased. The average diameter was 50 nm for nonirradiated control fibrils, while 4.4% of the irradiated collagen fibrils had a diameter greater than 100 nm. Irradiated collagen showed little evidence of damage. Well-preserved cross-striations were found in collagen fibrils at all doses of irradiation. Native amnion collagen irradiated with gamma rays demonstrated a slight increase in resistance to collagenase degradation compared with nonirradiated native collagen samples. Increased resistance to collagenase did not correlate with increasing irradiation dose. After 30 min of incubation at 37{degrees}C, both irradiated and nonirradiated collagen was completely digested by collagenase. However, gamma-irradiated collagen did become more sensitive to hydrolysis by trypsin. The higher the irradiation doses used, the greater sensitivity to trypsin was observed. At 0.25 Mrads irradiation only a slight increase was found. No marked differences in amino acid composition were noted among the high dose irradiated, low dose irradiated and control amnion collagen.

  6. Investigation on radiation degradation of carboxymethylcellulose by ionizing irradiation.

    PubMed

    Lee, Hee-Sub; Choi, Jong-Il; Kim, Jae-Hun; Lee, Kwang-Won; Chung, Young-Jin; Shin, Mee-Hye; Byun, Myung-Woo; Shin, Myung-Gon; Lee, Ju-Woon

    2009-01-01

    This study was done to compare the effects of irradiations with gamma-rays and electron beams, on the viscosity of the carboxymethylcellulose (CMC), on the functional groups of CMC, and on the production of radicals. It was observed that the relative viscosities decreased as the irradiation doses increased, but the decrease was more significant when irradiation with gamma rays. FT-IR spectra showed no significant difference between the gamma-ray and the electron beam irradiated samples. ESR spectra showed that the gamma-ray irradiation produced more radicals than electron beam irradiation in CMC. PMID:19285875

  7. Photoluminescence study on irradiated yttria stabilized zirconia

    NASA Astrophysics Data System (ADS)

    Halder, R.; Sengupta, Pranesh; Sudarsan, V.; Ghosh, A.; Ghosh, A.; Bhukta, A.; Sharma, G.; Samajdar, I.; Dey, G. K.

    2015-01-01

    The structural variations within monoclinic, tetragonal and cubic zirconia pellets with different amounts of yttria doping and its subsequent exposure to various proton, silver ion and gamma irradiation fluxes were investigated using photoluminescence spectroscopy. Upon ion irradiation color centers were produced at doses >1015 ions/cm2 resulting in purple coloration. The decrease in photoluminescence intensity was observed for proton irradiated pellets except for tetragonal zirconia (6YSZ: 6 mol% Y2O3 doped ZrO2). The anomalous behaviour in case of tetragonal zirconia may result from short range ordering of oxygen vacancies around Zr ions occurring in order to relieve the stress/lattice distortions associated with proton impingement.

  8. Health risk assessment of irradiated topaz

    SciTech Connect

    Nelson, J.W.; Baum, J.W. [Brookhaven National Lab., Upton, NY (United States)

    1993-01-01

    Irradiated topaz gemstones are currently processed for color improvement by subjecting clear stones to neutron or high-energy electron irradiations, which leads to activation of trace elements in the stones. Assessment of the risk to consumers required the identification and quantification of the resultant radionuclides and the attendant exposure. Representative stones from Brazil, India, Nigeria, Sri Lanka were irradiated and analyzed for gamma ray and beta particle emissions, using sodium iodide and germanium spectrometers; and Geiger-Muller, plastic and liquid scintillation, autoradiography, and thermoluminescent-dosimetry measurement techniques. Based on these studies and other information derived from published literature, dose and related risk estimates were made for typical user conditions. New criteria and methods for routine assays for acceptable release, based on gross beta and gross photon emissions from the stones, were also developed.

  9. Growth and shrinkage of precipitates under irradiation

    NASA Astrophysics Data System (ADS)

    Abyzov, A. S.; Slezov, V. V.; Tanatarov, L. V.

    1994-06-01

    The growth of second phase precipitates from the supersaturated solid solution under irradiation is investigated taking into account a new mechanism of precipitate dissolution. This mechanism is of a purely diffusion origin, i.e. it is based on diffusion outfluxes of point defects produced by irradiation within the precipitates into the host matrix, provided that the interface boundary is transparent for the point defects. The point defect production rate within a precipitate is proportional to its volume while the total diffusion influx of substitutional impurity atoms is proportional to its radius meaning that there exists a maximum size at which the precipitate growth rate equals the rate of its radiation-induced dissolution. This size is shown to be a stable one implying that under irradiation a stationary state can be achieved far away from the thermodynamic equilibrium.

  10. Migration and sensory evaluation of irradiated polymers

    NASA Astrophysics Data System (ADS)

    Stoffers, Niels H.; Linssen, Jozef P. H.; Franz, Roland; Welle, Frank

    2004-09-01

    The effects on ionising irradiation on polymer additives, monomers and polymers themselves have been investigated. Changes of initial concentrations of certain additives and monomers, a change in their specific migration as well as sensory changes of the polymers were examined. Polymer stabilizers such as Irganox 1076 and Irgafos 168 used in polyethylene were found to be degraded by ionising radiation. Decreased concentrations of stabilisers in polyolefins led to lower specific migration, however, not to lower overall migration into food simulants. Irganox 1076 levels in polystyrene did not change up to irradiation doses of 54 kGy. Sensory properties of LDPE, HDPE, PA6 and PA12 worsened, while sensory properties of PS improved with increasing irradiation doses.

  11. Enucleation versus plaque irradiation for choroidal melanoma

    SciTech Connect

    Straatsma, B.R.; Fine, S.L.; Earle, J.D.; Hawkins, B.S.; Diener-West, M.; McLaughlin, J.A.

    1988-07-01

    The Collaborative Ocular Melanoma Study (COMS) is an international, multicenter-controlled study. The organization includes an Executive Committee, Steering Committee, 6 Central Units, 32 Clinical Centers, and a Data and Safety Monitoring Committee. Scientifically, the COMS consists of (1) a randomized trial of patients with medium choroidal melanoma treated with enucleation versus iodine-125 plaque irradiation, (2) a randomized trial of patients with large choroidal melanoma treated with enucleation versus preenucleation external beam irradiation and enucleation, and (3) a prospective observational study of patients with small choroidal melanoma to determine whether a randomized trial of treatment is appropriate. In design and conduct of the COMS, special consideration is given to biostatistics and sample size considerations, iodine-125 plaque irradiation of choroidal melanoma, and coordinated ocular melanoma research. Recruitment is in progress. However, the pool of eligible patients is limited and the COMS needs the continued support and cooperation of ophthalmologists throughout the United States and Canada.

  12. Neutrophil myeloperoxidase destruction by ultraviolet irradiation

    SciTech Connect

    Hanker, J.; Giammara, B.; Strauss, G.

    1988-01-01

    The peroxidase activity of enriched leukocyte preparations on coverslips was determined cytochemically with a newly developed method. The techniques utilizes diaminobenzidine medium and cupric nitrate intensification and is suitable for analysis with light microscopy, SEM, and TEM. Blood specimens from control individuals were studied with and without in vitro UV irradiation and compared with those from psoriasis patients exposed therapeutically to various types of UV in phototherapy. All UV irradiated samples showed diminished neutrophil myeloperoxidase (MP) activity although that of the principal eosinophil peroxidase was unaffected. The SEMs supported the contention that decreased neutrophil MP activity might be related to UV induced degranulation. It is believed to be possible, eventually, to equate the observed MP degranulation effect after UV irradiation with diminished ability to fight bacterial infections.

  13. Horizontal modular dry irradiated fuel storage system

    DOEpatents

    Fischer, Larry E. (Los Gatos, CA); McInnes, Ian D. (San Jose, CA); Massey, John V. (San Jose, CA)

    1988-01-01

    A horizontal, modular, dry, irradiated fuel storage system (10) includes a thin-walled canister (12) for containing irradiated fuel assemblies (20), which canister (12) can be positioned in a transfer cask (14) and transported in a horizontal manner from a fuel storage pool (18), to an intermediate-term storage facility. The storage system (10) includes a plurality of dry storage modules (26) which accept the canister (12) from the transfer cask (14) and provide for appropriate shielding about the canister (12). Each module (26) also provides for air cooling of the canister (12) to remove the decay heat of the irradiated fuel assemblies (20). The modules (26) can be interlocked so that each module (26) gains additional shielding from the next adjacent module (26). Hydraulic rams (30) are provided for inserting and removing the canisters (12) from the modules (26).

  14. Growth-irradiance relationships in phytoplankton

    SciTech Connect

    Falkowski, P.G.; Dubinsky, Z.; Wyman, K.

    1985-03-01

    The steady state growth rates of three species of marine phytoplankton, Thalassiosira weisflogii, Isochrysis galbana, and Prorocentrum micans, were followed in turbidostat culture. At each growth irradiance, photosynthesis and respiration were measured by following changes in oxygen. Together with measurements of optical absorption cross sections, cellular chlorophyll, carbon and nitrogen, and excretion rates as well as knowledge of the quantum flux, the quantum requirement for growth and photosynthesis were calculated. Our results suggest that variations in growth rate caused by changes in irradiance may be related to changes in respiration rates relative to growth as well as changes in optical absorption cross sections for a given species. Interspecific differences in growth rate at a given irradiance are not related to changes in respiration however, but are primarily attributable to differences in optical absorption cross sections normalized to chlorophyll and differences in chlorophyll:carbon ratios.

  15. Neutron irradiation effects in uranium monosulfide

    NASA Astrophysics Data System (ADS)

    Matsui, H.; Nakashima, S.; Katori, K.; Tamaki, M.; Kirihara, T.

    1982-10-01

    Uranium monosulfide (US) was irradiated to investigate the effects of fission damage. Post-irradiation examinations were done by measuring the electrical resistivity, and partly the magnetic properties, at low temperature. The lattice parameter and the electrical resistivity measured at room temperature just after the irradiations showed an increase starting at a fission dose of 1 × 10 16 fissions/cm 3 and attaining a maximum at 3 × 10 16 fissions/cm 3. After that, a saturation of both increases persiste until 3 × 10 17 fissions/cm 3. The low-temperature electrical resistivity in the magnetic ordered state (ferromagnetic transition, T c, at about 180 K) increased remarkably, while decreasing drastically in the magnetization, with increasing fission dose, apparently corresponding to the lattice expansion. In addition, the Curie point ( T c) shifted to lower temperatures with accumulating fission damage.

  16. Alkali ion exchange in ?-irradiated glasses

    NASA Astrophysics Data System (ADS)

    Ojovan, Michael I.; Lee, William E.

    2004-12-01

    The alkali ion exchange of ?-irradiated glasses was investigated using the structural energy barrier model for ion exchange of glasses. It is shown that rates of alkali ion exchange have a non-Arrhenius behaviour depending both on irradiation dose and dose rate. For this reason some effects cannot be simulated by external irradiation and require in situ measurements. Higher doses and dose rates of ?-radiation lead to increased ion exchange rates. Significant changes occur in the activation energies demonstrating a many times decrease depending on glass composition. Radiation-induced changes are higher at relatively low temperatures being diminished by increased glass temperature. Numerical estimations show that changes in alkali ion exchange kinetics occur below the glass network damaging doses.

  17. Heavy ion irradiation of crystalline water ice

    E-print Network

    Dartois, E; Boduch, P; Brunetto, R; Chabot, M; Domaracka, A; Ding, J J; Kamalou, O; Lv, X Y; Rothard, H; da Silveira, E F; Thomas, J C

    2015-01-01

    Under cosmic irradiation, the interstellar water ice mantles evolve towards a compact amorphous state. Crystalline ice amorphisation was previously monitored mainly in the keV to hundreds of keV ion energies. We experimentally investigate heavy ion irradiation amorphisation of crystalline ice, at high energies closer to true cosmic rays, and explore the water-ice sputtering yield. We irradiated thin crystalline ice films with MeV to GeV swift ion beams, produced at the GANIL accelerator. The ice infrared spectral evolution as a function of fluence is monitored with in-situ infrared spectroscopy (induced amorphisation of the initial crystalline state into a compact amorphous phase). The crystalline ice amorphisation cross-section is measured in the high electronic stopping-power range for different temperatures. At large fluence, the ice sputtering is measured on the infrared spectra, and the fitted sputtering-yield dependence, combined with previous measurements, is quadratic over three decades of electronic ...

  18. Laboratory for Characterization of Irradiated Graphite

    SciTech Connect

    Karen A. Moore

    2010-03-01

    The newly completed Idaho National Laboratory (INL) Carbon Characterization Laboratory (CCL) is located in Labs C19 and C20 of the Idaho National Laboratory Research Center (IRC). The CCL was established under the Next Generation Nuclear Plant (NGNP) Project to support graphite and ceramic composite research and development activities. The research is in support of the Advanced Graphite Creep (AGC) experiment — a major material irradiation experiment within the NGNP Graphite program. The CCL is designed to characterize and test low activated irradiated materials such as high purity graphite, carbon-carbon composites, and silicon-carbide composite materials. The laboratory is fully capable of characterizing material properties for both irradiated and nonirradiated materials.

  19. Photoluminescence character of Xe ion irradiated sapphire

    NASA Astrophysics Data System (ADS)

    Yin, Song; Xie, Er-qing; Zhang, Chong-hong; Wang, Zhi-guang; Zhou, Li-hong; Ma, Yi-Zhong; Yao, Cun-feng; Zang, Hang; Liu, Chun-bao; Sheng, Yan-bin; Gou, Jie

    2008-06-01

    In the present work the photoluminescence (PL) character of sapphire implanted with 180 keV Xe and irradiated with 308 MeV Xe ions was studied. The virgin, implanted and irradiated samples were investigated by PL and Fourier transform infrared (FTIR) spectra measurements. The obtained PL spectra showed the maximum emission bands at 2.75, 3.0 and 3.26 eV for the implanted fluence of 1.0 × 10 15 ions/cm 2 and at 2.4 and 3.47 eV for the irradiated fluence of 1.0 × 10 13 ions/cm 2. The FTIR spectra showed a broaden absorption band between 460 and 630 cm -1, indicating that strong damaged region formed in Al 2O 3.

  20. Dosimetry procedures for an industrial irradiation plant

    NASA Astrophysics Data System (ADS)

    Grahn, Ch.

    Accurate and reliable dosimetry procedures constitute a very important part of process control and quality assurance at a radiation processing plant. ?-Dose measurements were made on the GBS 84 irradiator for food and other products on pallets or in containers. Chemical dosimeters wre exposed in the facility under conditions of the typical plant operation. The choice of the dosimeter systems employed was based on the experience in chemical dosimetry gained over several years. Dose uniformity information was obtained in air, spices, bulbs, feeds, cosmetics, plastics and surgical goods. Most products currently irradiated require dose uniformity which can be efficiently provided by pallet or box irradiators like GBS 84. The radiation performance characteristics and some dosimetry procedures are discussed.

  1. Biological effects of millimeter-wave irradiation

    SciTech Connect

    Furia, L.

    1986-01-01

    Millimeter waves (mm-waves) have been reported to influence various biological functions, including growth of Escherichia coli and Saccharomyces cerevisiae, induction of lambda phage and colicin in E. coli, DNA and RNA synthesis. Many reports were characterized by a strong frequency dependence and the low power needed to induce the effect. Many of the reported effects, however, have not been confirmed by independent investigations. In this thesis the potential effects of mm-wave irradiation on biological systems have been assessed. The published literature has been reviewed in detail. Contrasting reports have been compared, and possible causes of discrepancies pointed out. In order to verify if the growth rate of yeast is dependent on the irradiation frequency, cultures of Sacch. cerevisiae have been irradiated for four hours with cw mm-waves stabilized in frequency to +/-10 Hz. The growth rate was determined optically and plate counts were performed at the end of each experiment. No variations larger than +/-4% were detected between the growth rates of irradiated and sham-irradiated cultures, and these differences were not significant at the 95% confidence limit. These results correlated favorably with the plate counts. An extensive comparison of the results with the previous, contrasting, reports is given. A model of cell membranes has been used in attempt to identify a possible site of interaction of mm-waves. Raman spectroscopy was used to determine if mm-wave irradiation affects the conformational state of phospholipids in liposomes. This investigation adds to a growing list of studies showing that mm-waves are not able to induce detectable effects in a variety of eukaryotic and prokaryotic microorganisms.

  2. Irradiation of meat products, chicken and use of irradiated spices for sausages

    NASA Astrophysics Data System (ADS)

    Kiss, I. F.; Beczner, J.; Zachariev, Gy.; Kovács, S.

    The shelf-life of packed minced meat has been increased at least threefold at 4°C by applying a 2 kGy dose. Results have been confirmed by detailed quatitative microbiological examinations. Sensory evaluations show no significant difference between the unirradiated samples. The optimal average dose was 4 kGy for packed-frosen chicken. The number of mesophilic aerobic microbes was reduced by 2, that of psychrotolerant by 2-3 and that of Enterbacteriaceae by 3-4 orders of magnitude by 4 kGy. S. aureus and Salmonella could not be detected in the irradiated samples. In sensory evaluations there was no significant difference between untreated and irradiated samples. In 1984-1985 5100 kg irradiated chickens were marketed labelled as radiation treated. Irradiated spices (5 kGy) were used in the production of sausages (heat-treated and non-heat-treated) under industrial conditions. The microbiological contamination of irradiated spices was lower than that of ethylene oxide treated ones. The cell count in products made with irradiated spices was lower than in those made with unirradiated spices. The sausages proved to be of very good quality. In accordance with the permission, products were marketed and because of the low ratio of spices there was no need to declare them as using irradiated spices.

  3. Dyeing of ?-irradiated cotton with natural flavonoid dye extracted from irradiated onion shells (Allium cepa) powder

    NASA Astrophysics Data System (ADS)

    Rehman, Fazal-ur; Adeel, Shahid; Shahid, Muhammad; Bhatti, Ijaz Ahmad; Nasir, Faiza; Akhtar, Nasim; Ahmad, Zulfiqar

    2013-11-01

    Powder of Onion shells as a source of natural flavonoid dye (Quercetin) and cotton fabrics were exposed to absorbed doses of 2, 4, 6, 8 and 10 kGy using Cs-137 gamma irradiator. Irradiated and un-irradiated dye powder was used for extraction of quercetin as well as antibacterial, hemolytic and antioxidant activities were also determined to observe the effect of radiation. Furthermore, color strength and colourfastness of irradiated fabrics were improved by using pre and post-mordants such as alum and iron. It is found that 4 kGy is the optimal absorbed dose for extraction of natural quercetin extracted from onion shells while maximum color strength and acceptable fastness properties are obtained on dyeing of irradiated fabric at 60 °C keeping M:L of 1:30 using 10% alum as pre-mordant and 6% alum as post-mordant. Gamma irradiation has not only improved the color strength of the dye using irradiated cotton but also that of colourfastness properties.

  4. Low-temperature thermally-activated deformation and irradiation softening in neutron-irradiated molybdenum

    NASA Astrophysics Data System (ADS)

    Li, Meimei; Byun, T. S.; Snead, L. L.; Zinkle, S. J.

    2008-07-01

    The effect of neutron irradiation on low-temperature deformation of Mo in two heat treatments, i.e. annealed and stress-relieved, was investigated. Specimens were irradiated at reactor coolant temperature (˜80 °C) to doses ranging from 7.2 × 10 -5 to 0.28 dpa in the High Flux Isotope Reactor. Tensile tests were carried out between -50 and 100 °C at strain rates of 1 × 10 -5-1 × 10 -2 s -1. Thermal activation analysis based on tensile data was performed to understand the low-temperature deformation mechanism. Irradiation softening and reduced dependence on test temperature and strain rate of the yield stress was observed in the annealed Mo after low-dose neutron irradiation (<˜0.003 dpa). Higher dose neutron irradiation caused athermal hardening only. The stress-relieved Mo showed a weaker dependence on test temperature and strain rate of the yield stress than the annealed Mo, and the dependence of the yield stress of the stress-relieved Mo was nearly unchanged after irradiation. Comparison of the experimental values of activation parameters with the theoretical predictions of dislocation models indicates that the Fleischer model of interactions of dislocations with tetragonal strains gave a better description of the activation process than the double-kink model, which implies a scavenging effect. The reduced test temperature and strain rate dependence following irradiation may be explained by the decreased effective stress due to trapping of interstitial solute species by neutron-produced defects.

  5. Separation of sodium-22 from irradiated targets

    DOEpatents

    Taylor, Wayne A. (Los Alamos, NM); Jamriska, David (Los Alamos, NM)

    1996-01-01

    A process for selective separation of sodium-22 from an irradiated target including dissolving an irradiated target to form a first solution, contacting the first solution with hydrated antimony pentoxide to selectively separate sodium-22 from the first solution, separating the hydrated antimony pentoxide including the separated sodium-22 from the first solution, dissolving the hydrated antimony pentoxide including the separated sodium-22 in a mineral acid to form a second solution, and, separating the antimony from the sodium-22 in the second solution.

  6. Electron beam irradiation of fluoropolymers containing polyethers

    Microsoft Academic Search

    E. Bucio; G. Burillo; F. Tapia; E. Adem; G. Cedillo; P. E. Cassidy

    2009-01-01

    A highly fluorinated monomer, 1,3-bis(1,1,1,3,3,3-hexafluoro-2-pentafluorophenyl methoxy-2-propyl)benzene (12F-FBE) was polymerized with some diphenols by polycondensation and then was electron beam irradiated between 100 and 1000kGy to determine degradation radiochemistry yield (Gs) by gel permeation chromatography (GPC). The samples were characterized after irradiation by DSC, FTIR, and nuclear magnetic resonance (NMR). The fluoropolymers show apparent degradation in mechanical properties at 300kGy, except

  7. Gamma irradiation of the prenatal mouse dentition

    E-print Network

    Kerley, Michael Auston

    1969-01-01

    of the developing tooth, or the appearance of the dental papil!a. It was concluded that ccntinuous gamma irradiation at the dos= rate used iti this study has no effect on the developing dentition of the mouse embryo. ACKiiONLEDGEh1ENTS The author expresses...~lARY AND CONCLUSIONS LIST OF REFERENCES I3 16 44 47 VITA 54 LIST OP TABLES Table I. Radiation Dose Received by the Irradiated Anima I s Page 11 LIST OF FIGURES Figure Page 12 &lay fetal mouse. Frontal section through dental lamina of lower first molar...

  8. Extrasolar Giant Planets under Strong Stellar Irradiation

    NASA Astrophysics Data System (ADS)

    Seager, S.; Sasselov, D. D.

    1998-08-01

    We investigate irradiation of extrasolar giant planets (EGPs) by treating the radiative transfer in detail, so that the flux from the parent star interacts with all relevant depths of the planetary atmosphere with no need for a preassumed albedo. Rayleigh scattering (in dust-free models) increases the EGP's flux by orders of magnitude shortward of the Ca II H and K doublet (3930 Å), and the spectral features of the parent star are exactly reflected. The inclusion of dust increases the reflected flux in the blue. In the optical and near-IR, the thermal absorption of the planet takes over, but the absorption features are changed by the irradiation.

  9. The puridec range of gamma irradiation plants

    NASA Astrophysics Data System (ADS)

    Reuter, G. W.

    1995-02-01

    In 1992 Amersham International plc. and NUKEM GmbH agreed to cooperate in the field of industrial gamma irradiation plants. Consequently the brand "PURIDEC" was founded, to handle the common business worldwide. Amersham Int. plc. has been a leading company in manufacturing and transport of Co60 sources for more than 30 years while NUKEM looks back to three decades of experience in engineering and realization of nuclear plants and installations. Based on this vast experience a range of industrial irradiation plants has been developed that satisfies the individual demands of our customers. This paper gives an overview of PURIDEC's range of plants including those with dry and twin pool source storage.

  10. Determination of irradiation dose and distinguishing between irradiated and non irradiated fish meat by real-time PCR.

    PubMed

    ?akalar, Ergün; Mol, Sühendan

    2015-09-01

    In this study, the effects of gamma irradiation on the DNA of fish (Oncorhynchus mykiss) by real-time PCR were studied. Fish (O. mykiss) were exposed to radiation doses of 0.250, 0.500, 1, 3, 5, 7, and 9kGy in a gamma cell. Primers were designed for regions with different lengths of both nuclear and mitochondrial DNA, and each primer was used to amplify the DNA from irradiated samples. The amplicon curves for mitochondrial and nuclear DNA, and the correlations among the curves, were obtained. The Ct values for a 519bp region of the 18S RNA gene on nuclear DNA correlated appropriately. Radiation doses applied to the fillets were estimated using the standard curve data obtained from the correlation values, and the DNA damage caused by each dose was calculated. As a consequence, a molecular methodology to analyze irradiated fish meat qualitatively and also for the estimation of administered dose was developed. This method allowed analysis of irradiated fish, which had been stored for up to 3months with a dose limit of approximately 0.5kGy. PMID:25842321

  11. Understanding the Irradiation Behavior of Zirconium Carbide

    SciTech Connect

    Motta, Arthur; Sridharan, Kumar; Morgan, Dane; Szlufarska, Izabela

    2013-10-11

    Zirconium carbide (ZrC) is being considered for utilization in high-temperature gas-cooled reactor fuels in deep-burn TRISO fuel. Zirconium carbide possesses a cubic B1-type crystal structure with a high melting point, exceptional hardness, and good thermal and electrical conductivities. The use of ZrC as part of the TRISO fuel requires a thorough understanding of its irradiation response. However, the radiation effects on ZrC are still poorly understood. The majority of the existing research is focused on the radiation damage phenomena at higher temperatures (>450{degree}C) where many fundamental aspects of defect production and kinetics cannot be easily distinguished. Little is known about basic defect formation, clustering, and evolution of ZrC under irradiation, although some atomistic simulation and phenomenological studies have been performed. Such detailed information is needed to construct a model describing the microstructural evolution in fast-neutron irradiated materials that will be of great technological importance for the development of ZrC- based fuel. The goal of the proposed project is to gain fundamental understanding of the radiation-induced defect formation in zirconium carbide and irradiation response (ZrC) by using a combination of state-of-the-art experimental methods and atomistic modeling. This project will combine (1) in situ ion irradiation at a specialized facility at a national laboratory, (2) controlled temperature proton irradiation on bulk samples, and (3) atomistic modeling to gain a fundamental understanding of defect formation in ZrC. The proposed project will cover the irradiation temperatures from cryogenic temperature to as high as 800{degree}C, and dose ranges from 0.1 to 100 dpa. The examination of this wide range of temperatures and doses allows us to obtain an experimental data set that can be effectively used to exercise and benchmark the computer calculations of defect properties. Combining the examination of radiation-induced microstructures mapped spatially and temporally, microstructural evolution during post-irradiation annealing, and atomistic modeling of defect formation and transport energetics will provide new, critical understanding about property changes in ZrC. The behavior of materials under irradiation is determined by the balance between damage production, defect clustering, and lattice response. In order to predict those effects at high temperatures so targeted testing can be expanded and extrapolated beyond the known database, it is necessary to determine the defect energetics and mobilities as these control damage accumulation and annealing. In particular, low-temperature irradiations are invaluable for determining the regions of defect mobility. Computer simulation techniques are particularly useful for identifying basic defect properties, especially if closely coupled with a well-constructed and complete experimental database. The close coupling of calculation and experiment in this project will provide mutual benchmarking and allow us to glean a deeper understanding of the irradiation response of ZrC, which can then be applied to the prediction of its behavior in reactor conditions.

  12. Low dose rate proton irradiation of quartz crystal resonators

    Microsoft Academic Search

    R. Koga; M. D. Looper; S. D. Pinkerton; W. J. Stapor; P. T. McDonald

    1996-01-01

    Quartz crystal resonators were systematically irradiated with 65 MeV protons to characterize low dose rate radiation-induced degradation. Results indicate: (1) test samples that exhibit large frequency shifts during testing tend to show large frequency shifts prior to irradiation, or during off-irradiation periods; (2) for radiation-sensitive samples, short-term effects seem to decrease after each irradiation on\\/off cycle (moreover, those devices in

  13. IRRADIATION EFFECTS ON THE PHYSICAL CHARACTERISTICS OF SEWAGE SLUDGE

    SciTech Connect

    Lee, M-J.; Lee, J-K.; Yoo, D-H.; Ho, K.

    2004-10-05

    The radiation effects on the physical characteristic of the sewage sludge were studied in order to obtain information which will be used for study on the enhancement of the sludge's dewaterability. Water contents, capillary suction time, zeta potential, irradiation dose, sludge acidity, total solid concentration, sludge particle size and microbiology before and after irradiation were investigated. Irradiation gave an effect on physical characteristics sludge. Water content in sludge cake could be reduced by irradiation at the dose of 10kGy.

  14. Enhanced variance of irradiance from target glint

    Microsoft Academic Search

    C. M. McIntyre; J. R. Kerr; M. H. Lee; J. H. Churnside

    1979-01-01

    The enhanced variance of detector irradiance in a turbulent atmosphere from a laser-illuminated target exhibiting a glint that is small relative to the illuminating beam rather than one-way or entirely diffuse reflection is examined. Light propagation from the transmitter to the target and back to the receiver after scattering by an appropriate target model was analyzed and the variance of

  15. Irradiation Processing Department monthly report, June 1962

    SciTech Connect

    Not Available

    1992-07-13

    This document details activities of the Irradiation Processing Department during the month of June, 1962. A general summary is included at the start of the report, after which the report is divided into the following sections: Research and Engineering Operations; Production and Reactor Operations; Facilities Engineering Operation; and NPR Project.

  16. New pallet irradiation for Gammaster International

    NASA Astrophysics Data System (ADS)

    Möhlmann, Mr. J. H. F.

    1993-07-01

    State of the art technology offers many opportunities to improve production process with ionizing radiation. Also the requirements to this process become more and more stringent; who was aware of the ISO-9000 Standards? Now it is a necessary concept? Internal and external audits, in particular by Regulatory Bodies such as the FDA and DHSS/MCA, are necessary and commonplace requirements when operating in the Healthcare and Pharmaceutical sectors. Efficiency is a major requirement for industry and also for our radiation business. With all the above mentioned items in mind, Gammaster International B.V. in close cooperation with Nordion International Inc. has developed and built a new type Pallet Irradiator. In this new concept, our 22 years experience in gamma processing and the expertise gained in 10 years of operation of pallet irradiators was incorporated. For this irradiator Gammaster International designed and built a new process control console, incorporating state of the art technology such as: - A well-balanced safety system - A control panel, with status indication for all essential operating and safety parameters - Advances warning for necessary maintenance work - Automatic timer-setting control in addition to an automatic timer setting modification - Clear indication of the position of the product inside the unit and its status - Fully automatic product information generated when the product leaves the irradiation unit - Visual process control with the help of a color monitor - Incremental dose-control - Fault identification

  17. X-ray irradiation of yeast cells

    NASA Astrophysics Data System (ADS)

    Masini, Alessandra; Batani, Dimitri; Previdi, Fabio; Conti, Aldo; Pisani, Francesca; Botto, Cesare; Bortolotto, Fulvia; Torsiello, Flavia; Turcu, I. C. Edmond; Allott, Ric M.; Lisi, Nicola; Milani, Marziale; Costato, Michele; Pozzi, Achille; Koenig, Michel

    1997-10-01

    Saccharomyces Cerevisiae yeast cells were irradiated using the soft X-ray laser-plasma source at Rutherford Laboratory. The aim was to produce a selective damage of enzyme metabolic activity at the wall and membrane level (responsible for fermentation) without interfering with respiration (taking place in mitochondria) and with nuclear and DNA activity. The source was calibrated by PIN diodes and X-ray spectrometers. Teflon stripes were chosen as targets for the UV laser, emitting X-rays at about 0.9 keV, characterized by a very large decay exponent in biological matter. X-ray doses to the different cell compartments were calculated following a Lambert-Bouguet-Beer law. After irradiation, the selective damage to metabolic activity at the membrane level was measured by monitoring CO2 production with pressure silicon detectors. Preliminary results gave evidence of pressure reduction for irradiated samples and non-linear response to doses. Also metabolic oscillations were evidenced in cell suspensions and it was shown that X-ray irradiation changed the oscillation frequency.

  18. Heavy ion irradiation of thin gate oxides

    Microsoft Academic Search

    M. Ceschia; A. Paccagnella; M. Turrini; A. Candelori; G. Ghidini; J. Wyss

    2000-01-01

    We have studied the gate leakage current after heavy ion irradiation of MOS capacitors with thin gate oxides. In 3-nm and 4-nm oxides radiation-induced soft breakdown (RSB) occurs even after ion fluences as small as 100 ion hits on the device surface. The RSB conductive paths likely reproduce the ion hit distribution: some of them can drive a substantial fraction

  19. Mantle irradiation of the major salivary glands

    SciTech Connect

    Kaplan, P.

    1985-11-01

    Radiation given to the mantle field for treatment of Hodgkin's disease impinges on the submandibular and parotid glands at levels that have been both measured and calculated to be the complete tumor dose. This dosage is above the level of irradiation that has been shown to cause partial or complete loss of salivary gland function.

  20. Interactive Caustics Using Local Precomputed Irradiance

    E-print Network

    Wyman, Chris

    Interactive Caustics Using Local Precomputed Irradiance Chris Wyman*# Charles Hansen# Peter Shirley# *University of Iowa #University of Utah #12;What is a Caustic? Light focused by reflection off or refraction through specular objects #12;What is a Caustic? · Focusing implies integration ­ Over all points

  1. Pyroelectrochemical process for reprocessing irradiated nuclear fuels

    Microsoft Academic Search

    G. Brambilla; A. Sartorelli

    1981-01-01

    In a method for reprocessing irradiated nuclear fuels, the fuel to be reprocessed is dissolved in a fused-salt bath while absolute sulfuric acid is added dropwise to said bath, plutonium sulfate is thermally converted into the corresponding oxide, the uranium oxide is electrolytically deposited from the fused-salt bath as the electrolyte, the melted salts are recycled to the starting end

  2. Physiological measurements during radio-frequency irradiation.

    PubMed

    Frei, M; Jauchem, J; Heinmets, F

    1988-01-01

    Conventional techniques for monitoring physiological parameters are not suitable for use during RFR exposure. This research note describes transduction methods involving the use of fluorocarbon leads and a pneumatic pressure transducer for reliable measurement of the ECG and respiratory rate in anesthetized or restrained rats during radiofrequency irradiation. PMID:3193340

  3. Hyperparathyroidism After Irradiation for Childhood Malignancy

    SciTech Connect

    McMullen, Todd; Bodie, Greg [University of Sydney Endocrine Surgical Unit, Sydney, NSW (Australia); Gill, Anthony [Department of Anatomical Pathology, Royal North Shore Hospital and University of Sydney, Sydney, NSW (Australia); Ihre-Lundgren, Catharina [University of Sydney Endocrine Surgical Unit, Sydney, NSW (Australia); Shun, Albert [Department of Surgery, Children's Hospital at Westmead, Sydney (Australia); Bergin, Mary [Late Effects Oncology Clinic, Children's Hospital at Westmead, Sydney (Australia); Stevens, Graham [Oncology Service, Auckland Hospital, Auckland (New Zealand); Delbridge, Leigh [University of Sydney Endocrine Surgical Unit, Sydney, NSW (Australia)], E-mail: leighd@med.usyd.edu.au

    2009-03-15

    Purpose: To examine the occurrence of hyperparathyroidism in a cohort of patients undergoing combined parathyroid and thyroid surgery after previous head-and-neck irradiation for childhood malignancy. Methods and Materials: This is a retrospective cohort study for the years 1996 to 2007. The study group comprised patients undergoing surgery in University of Sydney Endocrine Surgical Unit who had received previous head-and-neck irradiation in childhood and who were identified as having pathologic thyroid and parathyroid characteristics. Results: A total of 53 patients were identified in whom head-and-neck irradiation for the treatment of childhood malignancy had been documented. In each of the cases, thyroid disease was the primary reason for referral for surgery. Five of these patients (10%) were found to exhibit coexisting hyperparathyroidism. The latency period for hyperparathyroidism was less than 20 years in 4 of the 5 cases. There were four conventional parathyroid adenomas and one parathyroid lipoadenoma. All patients exhibited a significant decrease in postoperative calcium levels after surgery. Conclusions: To our knowledge, this is the first study to document the significant risk of hyperparathyroidism after radiation exposure for childhood malignancy. The timeframe for development of disease is much shorter than that published for individuals who have undergone irradiation for benign diseases. High doses of therapeutic radiation at a young age make childhood survivors of malignancy at especially high risk for developing hyperparathyroidism.

  4. Migration and sensory evaluation of irradiated polymers

    Microsoft Academic Search

    Niels H Stoffers; Jozef P. H Linssen; Roland Franz; Frank Welle

    2004-01-01

    The effects on ionising irradiation on polymer additives, monomers and polymers themselves have been investigated. Changes of initial concentrations of certain additives and monomers, a change in their specific migration as well as sensory changes of the polymers were examined. Polymer stabilizers such as Irganox 1076 and Irgafos 168 used in polyethylene were found to be degraded by ionising radiation.

  5. The irradiation facility at the AGOR cyclotron

    NASA Astrophysics Data System (ADS)

    Brandenburg, Sytze; Ostendorf, Reint; Hofstee, Mariet; Kiewiet, Harry; Beijers, Hans

    2007-08-01

    The KVI is conducting radiobiology research using protons up to 190 MeV from the superconducting AGOR cyclotron in collaboration with the University Medical Center Groningen (UMCG) since 1998. Using the same set-up, we have started irradiations for radiation hardness studies of detectors and components for the European Space Agency (ESA) and industrial parties. For these irradiations, we use either mono-energetic protons or a simulated solar flare energy spectrum with fluxes up to 5 × 10 8 protons cm -2 s -1. Furthermore, tests of radiation effects such as single event upsets, are being performed with intensities down to a few particles/s. Different energies are achieved by degrading the primary beam energy. We are currently developing the capability for heavy ion irradiations in air with beams up to Xe at beam energies between 15 and 45 MeV per nucleon. Performing the irradiations in air simplifies handling and monitoring of the device under test. The high energy allows penetration to the active layer of electronic devices, without modifications to the chip housing. The different ions provide a wide range in LET.

  6. Solar Forecasting System and Irradiance Variability Characterization

    E-print Network

    .1 Photovoltaic Systems: Report 3 Development of data base allowing managed access to statewide PV and insolation. It also presents details of HNEI-developed statistical techniques for characterizing irradiance September 2014 HAWAI`I NATURAL ENERGY INSTITUTE School of Ocean & Earth Science & Technology ­ University

  7. Low energy electron irradiation of an apple

    E-print Network

    Brescia, Giovanni Batista

    2002-01-01

    is the need to achieve a uniform dose over the entire surface of convoluted shapes. The main goal of this research was to calculate the dose distribution produced by low energy electron irradiation of a typical complex shape, an apple, using Monte Carlo...

  8. Thymic irradiation and chronic myelogenous leukemia

    Microsoft Academic Search

    K. Shimaoka; J. E. Sokal

    1977-01-01

    Two cases of Ph positive chronic myelogenous leukemia with a history of thymic irradiation are presented. Both patients received radiation therapy from low voltage x-ray equipment at two to three months of age. Leukemia developed 18 and 22 years later. Presentation, response to antileukemic therapy, and clinical course did not differ from that of other patients with this disease treated

  9. Irradiated gases transferred without contamination or dilution

    NASA Technical Reports Server (NTRS)

    Bonn, J. L.; Kern, W.

    1967-01-01

    Vacuum chamber apparatus opens sealed canisters of irradiated gases and transfers the contents without contaminating the surrounding area, and without diluting or polluting the contained gases. The apparatus consists of the chamber, a valved piping manifold, and a special drill and sealed drilling access.

  10. Minimizing material damage using low temperature irradiation

    NASA Astrophysics Data System (ADS)

    Craven, E.; Hasanain, F.; Winters, M.

    2012-08-01

    Scientific advancements in healthcare driven both by technological breakthroughs and an aging and increasingly obese population have lead to a changing medical device market. Complex products and devices are being developed to meet the demands of leading edge medical procedures. Specialized materials in these medical devices, including pharmaceuticals and biologics as well as exotic polymers present a challenge for radiation sterilization as many of these components cannot withstand conventional irradiation methods. The irradiation of materials at dry ice temperatures has emerged as a technique that can be used to decrease the radiation sensitivity of materials. The purpose of this study is to examine the effect of low temperature irradiation on a variety of polymer materials, and over a range of temperatures from 0 °C down to -80 °C. The effectiveness of microbial kill is also investigated under each of these conditions. The results of the study show that the effect of low temperature irradiation is material dependent and can alter the balance between crosslinking and chain scission of the polymer. Low temperatures also increase the dose required to achieve an equivalent microbiological kill, therefore dose setting exercises must be performed under the environmental conditions of use.

  11. The Sun and Climate Solar Irradiance

    E-print Network

    Walter, Frederick M.

    The Sun and Climate #12;Solar Irradiance The Solar Constant f = 1.4 x 106 erg/cm2/s. Over is higher when the Sun is more magnetically active. ·The Sun was magnetically active, and the climate the Sun Drive Climate? #12;The Temperature's Rising #12;Sunspots and CO2 What is Cause and What is Effect

  12. Strain engineering in graphene by laser irradiation

    NASA Astrophysics Data System (ADS)

    Papasimakis, N.; Mailis, S.; Huang, C. C.; Al-Saab, F.; Hewak, D. W.; Luo, Z.; Shen, Z. X.

    2015-02-01

    We demonstrate that the Raman spectrum of graphene on lithium niobate can be controlled locally by continuous exposure to laser irradiation. We interpret our results in terms of changes to doping and mechanical strain and show that our observations are consistent with light-induced gradual strain relaxation in the graphene layer.

  13. Extrasolar Giant Planets under Strong Stellar Irradiation

    Microsoft Academic Search

    S. Seager; D. D. Sasselov

    1998-01-01

    We investigate irradiation of extrasolar giant planets (EGPs) by treating the radiative transfer in detail, so that the flux from the parent star interacts with all relevant depths of the planetary atmosphere with no need for a preassumed albedo. Rayleigh scattering (in dust-free models) increases the EGP's flux by orders of magnitude shortward of the Ca II H and K

  14. The sea transport of irradiated nuclear fuel

    SciTech Connect

    Miller, M.L.

    1995-12-31

    The paper describes the development of a transport system dedicated to the sea transport of irradiated nuclear fuel. It reviews the background to why shipments were required and the establishment of a specialist shipping company, Pacific Nuclear Transport Limited. A description of the ships, flasks and other equipment utilized is provided, together with details of key procedures implemented to ensure safety and customer satisfaction.

  15. SIPS: Solar Irradiance Prediction System Stefan Achleitner

    E-print Network

    Cerpa, Alberto E.

    -scaling capacities of renewable energy sources such as wind and solar. However, variability and uncertainty in power potentially limit the impact of fluctuations in solar power generation, specifically in cloudy days when infrastructure using wireless sensor networks (WSNs) to enable sensing of solar irradiance for solar power

  16. Nonintrusive irradiated fuel inventory confirmation technique

    SciTech Connect

    Dowdy, E.J.; Nicholson, N.; Caldwell, J.T.

    1980-01-01

    Successful tests showing correlation between the intensity of the Cerenkov glow surrounding irradiated fuel assemblies in water-filled spent fuel storage ponds and the exposure and cooling times of assemblies have been concluded. Fieldable instruments used in subsequent tests confirmed that such measurements can be made easily and rapidly, without fuel assembly movement or the introduction of apparatus into the storage ponds.

  17. Water hydraulic polymer components under irradiation

    Microsoft Academic Search

    Teresa Hernández; Eric R. Hodgson

    2007-01-01

    Polymers will be used as different sealing and glide components in the hydraulic remote handling systems for lifting and moving activities in ITER. The degradation of the polymer materials does not depend only on the radiation dose but also on the irradiation environment, and for remote handling hydraulic applications the components have to work in high humidity or water. In

  18. Studies of Solar EUV Irradiance from SOHO

    NASA Technical Reports Server (NTRS)

    Floyd, Linton

    2002-01-01

    The Extreme Ultraviolet (EUV) irradiance central and first order channel time series (COC and FOC) from the Solar EUV Monitor aboard the Solar and Heliospheric observatory (SOHO) issued in early 2002 covering the time period 1/1/96-31/1201 were analyzed in terms of other solar measurements and indices. A significant solar proton effect in the first order irradiance was found and characterized. When this effect is removed, the two irradiance time series are almost perfectly correlated. Earlier studies have shown good correlation between the FOC and the Hall core-to-wing ratio and likewise, it was the strongest component of the COC. Analysis of the FOC showed dependence on the F10.7 radio flux. Analysis of the CDC signals showed additional dependences on F10.7 and the GOES x-ray fluxes. The SEM FOC was also well correlated with thein 30.4 nm channel of the SOHO EUV Imaging Telescope (EIT). The irradiance derived from all four EIT channels (30.4 nm, 17.1 nm, 28.4 nm, and 19.5 nm) showed better correlation with MgII than F10.7.

  19. Studies of Solar EUV Irradiance from SOHO

    NASA Astrophysics Data System (ADS)

    Floyd, Linton

    2002-06-01

    The Extreme Ultraviolet (EUV) irradiance central and first order channel time series (COC and FOC) from the Solar EUV Monitor aboard the Solar and Heliospheric observatory (SOHO) issued in early 2002 covering the time period 1/1/96-31/1201 were analyzed in terms of other solar measurements and indices. A significant solar proton effect in the first order irradiance was found and characterized. When this effect is removed, the two irradiance time series are almost perfectly correlated. Earlier studies have shown good correlation between the FOC and the Hall core-to-wing ratio and likewise, it was the strongest component of the COC. Analysis of the FOC showed dependence on the F10.7 radio flux. Analysis of the CDC signals showed additional dependences on F10.7 and the GOES x-ray fluxes. The SEM FOC was also well correlated with thein 30.4 nm channel of the SOHO EUV Imaging Telescope (EIT). The irradiance derived from all four EIT channels (30.4 nm, 17.1 nm, 28.4 nm, and 19.5 nm) showed better correlation with MgII than F10.7.

  20. MECHANISM OF DISCOLORATION OF IRRADIATED POLYVINYL CHLORIDE

    Microsoft Academic Search

    Shun-Ichi Ohnishi; Yoshiharu Nakajima; Isamu Nitta

    1962-01-01

    The radiation chemical process in polyvinyl chloride was studied by ; means of electron spin resonance, optical spectroscopy, and measurement of gas ; evolution. The chief technique was to irradiate sampies at - 196 deg C and then ; follow the change or changes with rising temperature. primary radicals, such as --; CHâ--CH--CHâ-- and -- CHCl -- CH-- CHCl--, were

  1. Continuous wave laser irradiation of explosives

    SciTech Connect

    McGrane, Shawn D.; Moore, David S.

    2010-12-01

    Quantitative measurements of the levels of continuous wave (CW) laser light that can be safely applied to bare explosives during contact operations were obtained at 532 nm, 785 nm, and 1550 nm wavelengths. A thermal camera was used to record the temperature of explosive pressed pellets and single crystals while they were irradiated using a measured laser power and laser spot size. A visible light image of the sample surface was obtained before and after the laser irradiation. Laser irradiation thresholds were obtained for the onset of any visible change to the explosive sample and for the onset of any visible chemical reaction. Deflagration to detonation transitions were not observed using any of these CW laser wavelengths on single crystals or pressed pellets in the unconfined geometry tested. Except for the photochemistry of DAAF, TATB and PBX 9502, all reactions appeared to be thermal using a 532 nm wavelength laser. For a 1550 nm wavelength laser, no photochemistry was evident, but the laser power thresholds for thermal damage in some of the materials were significantly lower than for the 532 nm laser wavelength. No reactions were observed in any of the studied explosives using the available 300 mW laser at 785 nm wavelength. Tables of laser irradiance damage and reaction thresholds are presented for pressed pellets of PBX9501, PBX9502, Composition B, HMX, TATB, RDX, DAAF, PETN, and TNT and single crystals of RDX, HMX, and PETN for each of the laser wavelengths.

  2. Metal reflectance changes during intense laser irradiation

    Microsoft Academic Search

    W. T. Walter

    1979-01-01

    Measurements of specular and total reflectances of copper, aluminum, and brass surfaces in vacuum during laser irradiation by a Q-switched ruby laser pulse are presented. The thermal history of the metal surface was calculated during and following the laser pulse; results of the specular reflectance measurements show that it is a sensitive indicator of surface deformation. They also show that

  3. Calibration of the Odyssey Photosynthetic Irradiance Recorder for Absolute Irradiance Measures

    EPA Science Inventory

    Researchers are increasingly interested in measuring hotosynthetically active radiation (PAR) because of its importance in determining the structure and function of lotic ecosystems. The Odyssey Photosynthetic Irradiance Recorder is an affordable PAR meter gaining popularity am...

  4. In vitro irradiation system for radiobiological experiments

    PubMed Central

    2013-01-01

    Background Although two-dimensional (2-D) monolayer cell cultures provide important information on basic tumor biology and radiobiology, they are not representative of the complexity of three-dimensional (3-D) solid tumors. In particular, new models reproducing clinical conditions as closely as possible are needed for radiobiological studies to provide information that can be translated from bench to bedside. Methods We developed a novel system for the irradiation, under sterile conditions, of 3-D tumor spheroids, the in vitro model considered as a bridge between the complex architectural organization of in vivo tumors and the very simple one of in vitro monolayer cell cultures. The system exploits the same equipment as that used for patient treatments, without the need for dedicated and highly expensive instruments. To mimic the passage of radiation beams through human tissues before they reach the target tumor mass, 96-multiwell plates containing the multicellular tumor spheroids (MCTS) are inserted into a custom-built phantom made of plexiglass, the material most similar to water, the main component of human tissue. Results The system was used to irradiate CAEP- and A549-derived MCTS, pre-treated or not with 20 ?M cisplatin, with a dose of 20 Gy delivered in one session. We also tested the same treatment schemes on monolayer CAEP and A549 cells. Our preliminary results indicated a significant increment in radiotoxicity 20 days after the end of irradiation in the CAEP spheroids pre-treated with cisplatin compared to those treated with cisplatin or irradiation alone. Conversely, the effect of the radio- chemotherapy combination in A549-derived MCTS was similar to that induced by cisplatin or irradiation alone. Finally, the 20 Gy dose did not affect cell survival in monolayer CAEP and A549 cells, whereas cisplatin or cisplatin plus radiation caused 100% cell death, regardless of the type of cell line used. Conclusions We set up a system for the irradiation, under sterile conditions, of tumor cells grown in 3-D which allows for the use of the same dose intensities and schedules utilized in clinical practice. This irradiation system, coupled with 3-D cell cultures, has the potential to generate information that could be used to individually tailor radiotherapy. PMID:24180359

  5. Irradiation Embritlement in Alloy HT-­9

    SciTech Connect

    Serrano De Caro, Magdalena [Los Alamos National Laboratory

    2012-08-27

    HT-9 steel is a candidate structural and cladding material for high temperature lead-bismuth cooled fast reactors. In typical advanced fast reactor designs fuel elements will be irradiated for an extended period of time, reaching up to 5-7 years. Significant displacement damage accumulation in the steel is expected (> 200 dpa) when exposed to dpa-rates of 20-30 dpa{sub Fe}/y and high fast flux (E > 0.1 MeV) {approx}4 x 10{sup 15} n/cm{sup 2}s. Core temperatures could reach 400-560 C, with coolant temperatures at the inlet as low as 250 C, depending on the reactor design. Mechanical behavior in the presence of an intense fast flux and high dose is a concern. In particular, low temperature operation could be limited by irradiation embrittlement. Creep and corrosion effects in liquid metal coolants could set a limit to the upper operating temperature. In this report, we focus on the low temperature operating window limit and describe HT-9 embrittlement experimental findings reported in the literature that could provide supporting information to facilitate the consideration of a Code Case on irradiation effects for this class of steels in fast reactor environments. HT-9 has an extensive database available on irradiation performance, which makes it the best choice as a possible near-term candidate for clad, and ducts in future fast reactors. Still, as it is shown in this report, embrittlement data for very low irradiation temperatures (< 200 C) and very high radiation exposure (> 150 dpa) is scarce. Experimental findings indicate a saturation of DBTT shifts as a function of dose, which could allow for long lifetime cladding operation. However, a strong increase in DBTT shift with decreasing irradiation temperature could compromise operation at low service temperatures. Development of a deep understanding of the physics involved in the radiation damage mechanisms, together with multiscale computer simulation models of irradiation embrittlement will provide the basis to derive trendlines and quantitative engineering predictions.

  6. Dermal grafts to bony defects in irradiated and nonirradiated tissues

    SciTech Connect

    Lambert, P.M.; Patel, M.; Gutman, E.; Campana, H.A.

    1984-10-01

    Coverage of intraoral ablative defects presents many different problems. Free dermal grafts have been used to cover exposed mandibular bone in dogs. Grafts were placed in animals both before and after irradiation. Grafts were uniformly successful in animals not previously irradiated but failed when placed after irradiation.

  7. Strengthening of Carbon Fibres by Fast Neutron Irradiation

    Microsoft Academic Search

    B. F. Jones; I. D. Peggs

    1972-01-01

    To assess the effect of fast neutron irradiation on its structure and mechanical properties, a polyacrylonitrile (PAN) based fibre, manufactured by Rolls Royce Limited, was irradiated in the test facilities of the WR1 organic cooled nuclear reactor at temperatures in the range 400°-700° C. Mechanical tests were made at room temperature on the fibres before and after irradiation using a

  8. Ion irradiation effects in natural garnets: Comparison with zircon

    E-print Network

    Utsunomiya, Satoshi

    Ion irradiation effects in natural garnets: Comparison with zircon S. Utsunomiya, L.M. Wang, R ; Z ¼ 8) under ion-beam irradiation was investigated in order to compare its radiation susceptibility during the ion irradiation at high temperature. This behavior may be related to the phase relations

  9. Irradiation Applications in Vegetables and Fruits: A Review

    Microsoft Academic Search

    Ioannis S. Arvanitoyannis; Alexandros Ch. Stratakos; Panagiotis Tsarouhas

    2009-01-01

    There is an increasing trend both in advanced countries and many developing countries to centrally process fresh fruits and vegetables, properly packaged, for distribution and marketing. Irradiation technology proved to be effective in reducing post-harvest losses, and controlling the stored product insects and the microorganisms. Gamma irradiation was employed to restrain potato sprouting and kill pests in grain. Irradiation proved

  10. Modeling the Thermal Response of Porcine Cartilage to Laser Irradiation

    E-print Network

    Aguilar, Guillermo

    Modeling the Thermal Response of Porcine Cartilage to Laser Irradiation Sergio H. Díaz characterization of the thermal response of porcine cartilage to laser irradiation (Nd:YAG). The surface the temperature distribution in a slab of porcine nasal cartilage during laser irradiation. This model

  11. Effects of fast neutron irradiation on zirconium carbide

    NASA Astrophysics Data System (ADS)

    Snead, Lance L.; Katoh, Yutai; Kondo, Sosuke

    2010-04-01

    High-purity zone refined zirconium carbide has been fast neutron irradiated in the dose and temperature range of 1-10 × 10 25 N/m 2 ( E > 0.1 MeV) and 635-1480 °C, respectively. Non-irradiated and as-irradiated properties were measured including the lattice parameter, hardness and elastic modulus as determined through nano-indentation, thermal conductivity, and indentation fracture toughness. The effects of neutron irradiation on the microstructure were also determined though using transmission electron microscopy. The general finding of this paper, limited to this particular zone refined ZrC of nominal C/Zr ratio of 0.93, is that this ceramic is quite stable under neutron irradiation in the temperature and dose range studied. Measurement of lattice parameter before and after irradiation indicated a lack of significant crystalline strain due to irradiation. Only modest changes were observed in the mechanical properties of hardness, elastic modulus, and indentation fracture toughness. The thermal conductivity underwent a slight reduction near 1000 °C irradiation, though was essentially unchanged for 1300-1480 °C irradiation. Transmission electron microscopy revealed black-spot-type defects (likely Frank or other small loops) for irradiation at 670 °C, maturing to faulted Frank loops at 1280 °C. As the irradiation temperature increased from 1280 °C to the highest irradiation temperature, of 1496 °C, a transition to prismatic loops occurs.

  12. Raman spectroscopy of ion-irradiated astrophysically relevant materials

    Microsoft Academic Search

    G. A. Baratta; R. Brunetto; G. Leto; M. E. Palumbo; F. Spinella; G. Strazzulla

    2008-01-01

    Solid objects in space (interstellar grains, comets, interplanetary dust particles, etc.) are continuously exposed to energetic processes, such as cosmic ion irradiation, that influence their evolution. In this paper we present an experimental study, carried out by Raman spectroscopy, of the effects induced by ion irradiation on frozen ices and refractory materials. If the irradiated ice mixture contains a relevant

  13. Investigation on radiation degradation of carboxymethylcellulose by ionizing irradiation

    Microsoft Academic Search

    Hee-Sub Lee; Jong-Il Choi; Jae-Hun Kim; Kwang-Won Lee; Young-Jin Chung; Mee-Hye Shin; Myung-Woo Byun; Myung-Gon Shin; Ju-Woon Lee

    2009-01-01

    This study was done to compare the effects of irradiations with gamma-rays and electron beams, on the viscosity of the carboxymethylcellulose (CMC), on the functional groups of CMC, and on the production of radicals. It was observed that the relative viscosities decreased as the irradiation doses increased, but the decrease was more significant when irradiation with gamma rays. FT-IR spectra

  14. Neutron irradiation effects in GaN-based blue LEDs

    Microsoft Academic Search

    Chyishiun Li; S. Subramanian

    2003-01-01

    The neutron irradiation effects in GaN-based double heterojunction (DH) light-emitting diodes (LEDs) are investigated. Both optical and electrical properties showed significant degradation after neutron irradiation. The basic mechanisms responsible for both electrical and optical degradation are discussed. Some optical and electrical recovery due to an injection-enhanced annealing effect is observed in our irradiated LEDs.

  15. Resistance Capability of Irradiation Room by Explosive Load

    Microsoft Academic Search

    Liu Jinhui; Dou Jinlong

    2010-01-01

    Like nuclear power station, once the irradiation room was damaged, nuclear radiation accident will occur, causing the serious nuclear panic. Therefore, a typical structure of irradiation room was presented for an example in this paper to establish a method on evaluating the resistance capability of irradiation room by explosive load. Worrying about explosives under the radical source, the greatest explosives

  16. SHORT COMMUNICATION Microbeam irradiation of C. elegans nematode in microfluidic

    E-print Network

    Brenner, David Jonathan

    immobiliza- tion and imaging for irradiation of several whole living samples on a single clamp, here we show To perform high-throughput studies on the biological effects of ionizing radiation in vivo, we have Microbeam irradiation with microfluidic devices Á C. elegans microbeam irradiation Á Small animal microbeam

  17. Innovations — potential applications for an irradiator for pumpable liquids

    Microsoft Academic Search

    R. Langley; G. Reuter

    1998-01-01

    The successful operation of the irradiator built by PURIDEC\\/NUKEM for the Malaysian Institute of Technology for the radiation vulcanisation of natural rubber latex indicates that similar designs of irradiation plant might find application in other processes involving pumpable liquids. The authors review these applications and describe the benefits offered by the new irradiator design.

  18. Innovations — potential applications for an irradiator for pumpable liquids

    NASA Astrophysics Data System (ADS)

    Langley, R.; Reuter, G.

    1998-06-01

    The successful operation of the irradiator built by PURIDEC/NUKEM for the Malaysian Institute of Technology for the radiation vulcanisation of natural rubber latex indicates that similar designs of irradiation plant might find application in other processes involving pumpable liquids. The authors review these applications and describe the benefits offered by the new irradiator design.

  19. Sensitivity of ultrasonic nonlinearity to irradiated, annealed, and re-irradiated microstructure changes in RPV steels

    NASA Astrophysics Data System (ADS)

    Matlack, K. H.; Kim, J.-Y.; Wall, J. J.; Qu, J.; Jacobs, L. J.; Sokolov, M. A.

    2014-05-01

    The planned life extension of nuclear reactors throughout the US and abroad will cause reactor vessel and internals materials to be exposed to more neutron irradiation than was originally intended. A nondestructive evaluation (NDE) method to monitor radiation damage would enable safe and cost-effective continued operation of nuclear reactors. Radiation damage in reactor pressure vessel (RPV) steels causes microstructural changes that leave the material in an embrittled state. Nonlinear ultrasound is an NDE technique quantified by the measurable acoustic nonlinearity parameter, which is sensitive to microstructural changes in metallic materials such as dislocations, precipitates and their combinations. Recent research has demonstrated the sensitivity of the acoustic nonlinearity parameter to increasing neutron fluence in representative RPV steels. The current work considers nonlinear ultrasonic experiments conducted on similar RPV steel samples that had a combination of irradiation, annealing, re-irradiation, and/or re-annealing to a total neutron fluence of 0.5-5 × 1019 n/cm2 (E > 1 MeV) at an irradiation temperature of 290 °C. The acoustic nonlinearity parameter generally increased with increasing neutron fluence, and consistently decreased from the irradiated to the annealed state over different levels of neutron fluence. Results of the measured acoustic nonlinearity parameter are compared with those from previous measurements on other RPV steel samples. This comprehensive set of results illustrates the dependence of the measured acoustic nonlinearity parameter on neutron fluence, material composition, irradiation temperature and annealing.

  20. Detection of low amount of irradiated ingredients in non-irradiated precooked meals

    NASA Astrophysics Data System (ADS)

    Marchioni, Eric; Horvatovich, Peter; Ndiaye, Bara; Miesch, Michel; Hasselmann, Claude

    2002-03-01

    The application of the European Standards for the detection of irradiated food by thermoluminescence of silicates, electron-spin resonance spectroscopy of bones or gas chromatography-mass spectrometry of 2-alkylcyclobutanones does not allow the detection of irradiated ingredients included in small quantity in the matrix of a food which has not been irradiated, but which could be subjected to various processing technologies such as cooking, freezing or storage. The use of an enzymatic food hydrolysis carried out at moderated temperature, for the extraction of the food-contaminating silicate minerals and bone fragments, followed by a purification of the extracts by a high-density aqueous solution of sodium polytungstate, allows a simultaneous detection of weak inclusions (0.1% m:m) of irradiated spices and mechanically deboned turkey meat (MRM) included in various precooked foods. Moreover, the use of a supercritical fluid extraction procedure for the 2-alkylcyclobutanones or an additional purification step of the lipid extracts made it possible to lower the detection limit of the 2-alkylcyclobutanones radiation-induced from triglycerides. Using gas chromatography-mass spectrometry, down to 0.5% (m:m) of irradiated MRM included in non-irradiated chicken quenelles could be detected.

  1. Sensitivity of ultrasonic nonlinearity to irradiated, annealed, and re-irradiated microstructure changes in RPV steels

    SciTech Connect

    Matlack, Katie [Georgia Institute of Technology, Atlanta] [Georgia Institute of Technology, Atlanta; Kim, J-Y. [Georgia Institute of Technology, Atlanta] [Georgia Institute of Technology, Atlanta; Wall, J.J. [Electric Power Research Institute (EPRI)] [Electric Power Research Institute (EPRI); Jacobs, L.J. [Georgia Institute of Technology, Atlanta] [Georgia Institute of Technology, Atlanta; Sokolov, Mikhail A [ORNL] [ORNL

    2014-01-01

    The planned life extension of nuclear reactors throughout the US and abroad will cause reactor vessel and internals materials to be exposed to more neutron irradiation than was originally intended. A nondestructive evaluation (NDE) method to monitor radiation damage would enable safe and cost-effective continued operation of nuclear reactors. Radiation damage in reactor pressure vessel (RPV) steels causes microstructural changes that leave the material in an embrittled state. Nonlinear ultrasound is an NDE technique quantified by the measurable acoustic nonlinearity parameter, which is sensitive to microstructural changes in metallic materials such as dislocations, precipitates and their combinations. Recent research has demonstrated the sensitivity of the acoustic nonlinearity parameter to increasing neutron fluence in representative RPV steels. The current work considers nonlinear ultrasonic experiments conducted on similar RPV steel samples that had a combination of irradiation, annealing, re-irradiation, and/or re-annealing to a total neutron fluence of 0.5 5 1019 n/cm2 (E > 1 MeV) at an irradiation temperature of 290 C. The acoustic nonlinearity parameter generally increased with increasing neutron fluence, and consistently decreased from the irradiated to the annealed state over different levels of neutron fluence. Results of the measured acoustic nonlinearity parameter are compared with those from previous measurements on other RPV steel samples. This comprehensive set of results illustrates the dependence of the measured acoustic nonlinearity parameter on neutron fluence, material composition, irradiation temperature and annealing.

  2. Advances in the Hopkinson bar testing of irradiated/non-irradiated nuclear materials and large specimens.

    PubMed

    Albertini, Carlo; Cadoni, Ezio; Solomos, George

    2014-05-13

    A brief review of the technological advances of the Hopkinson bar technique in tension for the study of irradiated/non-irradiated nuclear materials and the development of this technology for large specimens is presented. Comparisons are made of the dynamic behaviour of non-irradiated and irradiated materials previously subjected to creep, low cycle fatigue and irradiation (2, 10 and 30 displacements per atom). In particular, complete results of the effect of irradiation on the dynamic mechanical properties of AISI304L steel, tested at 20, 400 and 550°C are presented. These high strain rate tests have been performed with a modified Hopkinson bar (MHB), installed inside a hot cell. Examples of testing large nuclear steel specimens with a very large Hopkinson bar are also shown. The results overall demonstrate the capability of the MHB to efficiently reproduce the material stress conditions in case of accidental internal and external dynamic loadings in nuclear reactors, thus contributing to the important process of their structural assessment. PMID:24711490

  3. Anterior cruciate ligament reconstruction with BPTB autograft, irradiated versus non-irradiated allograft: a prospective randomized clinical study

    Microsoft Academic Search

    Kang Sun; Shaoqi Tian; Jihua Zhang; Changsuo Xia; Cailong Zhang; Tengbo Yu

    2009-01-01

    The effect of using gamma irradiation to sterilize bone-patellar tendon-bone (BPTB) allograft on the clinical outcomes of\\u000a anterior cruciate ligament (ACL) reconstruction with irradiated allograft remains controversial. Our study was aimed to analyze\\u000a the clinical outcomes of arthroscopic ACL reconstruction with irradiated BPTB allograft compared with non-irradiated allograft\\u000a and autograft. All BPTB allografts were obtained from a single tissue bank

  4. ?-Irradiation of PEGd,lPLA and PEG-PLGA Multiblock Copolymers: I. Effect of Irradiation Doses

    Microsoft Academic Search

    R. Dorati; C. Colonna; M. Serra; I. Genta; T. Modena; F. Pavanetto; P. Perugini; B. Conti

    2008-01-01

    To evaluate the effects of different gamma irradiation doses on PEGd,lPLA and PEG-PLGA multiblock copolymers. The behaviour\\u000a of the multiblock copolymers to irradiation was compared to that of PLA, PLGA polymers. PEGd,lPLA, PEG-PLGA, PLA and PLGA\\u000a polymers were irradiated by using a 60Co irradiation source at 5, 15, 25 and 50 kGy total dose. Characterization was performed on all samples before

  5. Topographic correction algorithm for remotely sensed data accounting for indirect irradiance

    Microsoft Academic Search

    Wanchang Zhang; Yongnian Gao

    2011-01-01

    The solar irradiance incidents upon terrain surface are composed of three parts, i.e. direct solar irradiance, diffuse sky irradiance and reflected irradiance from the adjacent surface, respectively. Most of the topographic correction models only account for the topographic effect induced from direct solar irradiance, and few models take the topographic effects from the last two components of solar irradiance into

  6. Advanced irradiation protocols for the microbeam The microbeam was originally developed for irradiating cellular nuclei. Since then its uses have

    E-print Network

    Advanced irradiation protocols for the microbeam The microbeam was originally developed is no longer the only modality available for microbeam users. This demo showcases some of the modalities available to our microbeam users. Nuclear irradiation In nuclear irradiations, the cells are stained

  7. Analysis of the severe complications of irradiation of carcinoma of the uterine cervix: treatment with intracavitary radium and parametrial irradiation

    Microsoft Academic Search

    Abdurrahman Unal; Arthur D. Hamberger; Jan C. Seski; Gilbert H. Fletcher

    1981-01-01

    Between January 1967 and December 1974, 254 patients with carcinoma of the uterine cervix were treated with either intracavitary radium and parametrial irradiation or 2000 rad whole pelvis irradiation followed by intracavitary radium and parametrial irradiation. In general, these patients had tumors of relatively limited volume and vaginal and uterine anatomy that was favorable for intracavitary radium. Not all patients

  8. Development of radiation indicators to distinguish between irradiated and non-irradiated herbal medicines using HPLC and GC-MS.

    PubMed

    Kim, Min Jung; Ki, Hyeon A; Kim, Won Young; Pal, Sukdeb; Kim, Byeong Keun; Kang, Woo Suk; Song, Joon Myong

    2010-09-01

    The effects of high dose ?-irradiation on six herbal medicines were investigated using gas chromatography-mass spectrometry (GC/MS) and high-performance liquid chromatography (HPLC). Herbal medicines were irradiated at 0-50 kGy with (60)Co irradiator. HPLC was used to quantify changes of major components including glycyrrhizin, cinnamic acid, poncirin, hesperidin, berberine, and amygdalin in licorice, cinnamon bark, poncirin immature fruit, citrus unshiu peel, coptis rhizome, and apricot kernel. No significant differences were found between gamma-irradiated and non-irradiated samples with regard to the amounts of glycyrrhizin, berberine, and amygdalin. However, the contents of cinnamic acid, poncirin, and hesperidin were increased after irradiation. Volatile compounds were analyzed by GC/MS. The relative proportion of ketone in licorice was diminished after irradiation. The relative amount of hydrocarbons in irradiated cinnamon bark and apricot kernel was higher than that in non-irradiated samples. Therefore, ketone in licorice and hydrocarbons in cinnamon bark and apricot kernel can be considered radiolytic markers. Three unsaturated hydrocarbons, i.e., 1,7,10-hexadecatriene, 6,9-heptadecadiene, and 8-heptadecene, were detected only in apricot kernels irradiated at 25 and 50 kGy. These three hydrocarbons could be used as radiolytic markers to distinguish between irradiated (>25 kGy) and non-irradiated apricot kernels. PMID:20623272

  9. Structural changes of polytetrafluoroethylene during irradiation in oxygen

    NASA Astrophysics Data System (ADS)

    Liu, Shuling; Fu, Congli; Gu, Aiqun; Yu, Zili

    2015-04-01

    To study the effect of irradiation on PTFE structure and prepare modified PTFE micropowder, PTFE was irradiated with dose up to 4 MGy in oxygen at room temperature. The structures of both irradiated and unirradiated PTFE samples were comparatively characterized by IR, XPS, Raman spectra and XRD measurement. The results showed that new groups of acyl fluoride (COF), carboxylic acid (COOH) and trifluoromethyl (CF3) were formed under heavy radiation exposure in oxygen. In addition, the expansion of crystallite size or crystal lattice was first reported for the irradiated PTFE. The formation of new chemical groups and the expansion of crystallite size were elucidated by structural changes occurring in irradiation.

  10. Application of gamma irradiation for inhibition of food allergy

    NASA Astrophysics Data System (ADS)

    Byun, Myung-Woo; Lee, Ju-Woon; Yook, Hong-Sun; Jo, Cheorun; Kim, Hee-Yun

    2002-03-01

    This study was carried out to evaluate the application of food irradiation technology as a method for reducing food allergy. Milk ?-lactoglobulin, chicken egg albumin, and shrimp tropomyosin were used as model food allergens for experiments on allergenic and molecular properties by gamma irradiation. The amount of intact allergens in an irradiated solution was reduced by gamma irradiation depending upon the dose. These results showed that epitopes on the allergens were structurally altered by radiation treatment and that the irradiation technology can be applied to reduce allergenicity of allergic foods.

  11. Physical and chemical properties of ?-irradiated EVOH film

    NASA Astrophysics Data System (ADS)

    Jae Byun, Young; Hong, S. I.; Kim, K. B.; Jeon, D. H.; Kim, J. M.; Whiteside, W. S.; Jin Park, Hyun

    2007-06-01

    The effects of ?-irradiation on ethylene vinyl alcohol copolymer (EVOH) were investigated. Oxygen permeability decreased as irradiation dose increased in non-oriented (EF-CR), biaxially oriented (EF-XL) EVOH, and nylon/EVOH/PP. Irradiation increased tensile strength (TS) and elongation at break (% E) of EF-CR; whereas, TS of EF-XL was not significantly changed and % E of EF-XL decreased. Irradiation had no effect on TS and % E of nylon/EVOH/PP. Four volatile compounds, ?-caprolactam, 2-propyldecanol, 2-butyloctanol, and 2,3-diethyl-2,3-dimethyl-1,4-butanediol, were detected after irradiation. Optical properties were not changed.

  12. Gamma irradiation influence on physical properties of milk proteins

    NASA Astrophysics Data System (ADS)

    Cie?la, K.; Salmieri, S.; Lacroix, M.; Tien, C. Le

    2004-09-01

    Gamma irradiation was found to be an effective method for the improvement of both barrier and mechanical properties of the edible films and coatings based on calcium and sodium caseinates alone or combined with some globular proteins. Our current studies concern gamma irradiation influence on the physical properties of calcium caseinate-whey protein isolate-glycerol (1:1:1) solutions and gels, used for films preparation. Irradiation of solutions was carried out with Co-60 gamma rays applying 0 and 32 kGy dose. The increase in viscosity of solutions was found after irradiation connected to induced crosslinking. Lower viscosity values were detected, however, after heating of the solutions irradiated with a 32 kGy dose than after heating of the non-irradiated ones regarding differences in the structure of gels and resulting in different temperature-viscosity curves that were recorded for the irradiated and the non-irradiated samples during heating and cooling. Creation of less stiff but better ordered gels after irradiation arises probably from reorganisation of aperiodic helical phase and ?-sheets, in particular from increase of ?-strands, detected by FTIR. Films obtained from these gels are characterised by improved barrier properties and mechanical resistance and are more rigid than those prepared from the non-irradiated gels. The route of gel creation was investigated for the control and the irradiated samples during heating and the subsequent cooling.

  13. Microarchitecture of irradiated bone: comparison with healthy bone

    NASA Astrophysics Data System (ADS)

    Bléry, Pauline; Amouriq, Yves; Guédon, Jeanpierre; Pilet, Paul; Normand, Nicolas; Durand, Nicolas; Espitalier, Florent; Arlicot, Aurore; Malard, Olivier; Weiss, Pierre

    2012-03-01

    The squamous cell carcinomas of the upper aero-digestive tract represent about ten percent of cancers. External radiation therapy leads to esthetic and functional consequences, and to a decrease of the bone mechanical abilities. For these patients, the oral prosthetic rehabilitation, including possibilities of dental implant placement, is difficult. The effects of radiotherapy on bone microarchitecture parameters are not well known. Thus, the purpose of this study is to assess the effects of external radiation on bone micro architecture in an experimental model of 25 rats using micro CT. 15 rats were irradiated on the hind limbs by a single dose of 20 Grays, and 10 rats were non irradiated. Images of irradiated and healthy bone were compared. Bone microarchitecture parameters (including trabecular thickness, trabecular number, trabecular separation, connectivity density and tissue and bone volume) between irradiated and non-irradiated bones were calculated and compared using a Mann and Whitney test. After 7 and 12 weeks, images of irradiated and healthy bone are different. Differences on the irradiated and the healthy bone populations exhibit a statistical significance. Trabecular number, connectivity density and closed porosity are less important on irradiated bone. Trabecular thickness and separation increase for irradiated bone. These parameters indicate a decrease of irradiated bone properties. Finally, the external irradiation induces changes on the bone micro architecture. This knowledge is of prime importance for better oral prosthetic rehabilitation, including implant placement.

  14. Irradiation of Anastrepha obliqua (Diptera: Tephritidae) revisited: optimizing sterility induction.

    PubMed

    Toledo, Jorge; Rull, Juan; Oropeza, Azucena; Hernández, Emilio; Liedo, Pablo

    2004-04-01

    The effects of irradiation doses increasing from 0 to 100 Gy (1 Gy is energy absorbed in J kg(-1) of irradiated material) on fertility, flight ability, survival, and sterile male mating performance were evaluated for mass-reared Anastrepha obliqua (Macquart). High sterility values (> 98.2%) for irradiated males were obtained for doses as low as 25 Gy. Egg hatch was inhibited for irradiated males crossed with irradiated females at a low dose of 20 Gy. However, we estimated that to achieve 99.9% sterility (standard goal of many sterile insect technique programs), irradiation doses had to be increased to a dose between 50 and 75 Gy. At doses of 25 Gy and greater, we observed a decreasing trend in adult flight ability and an increasing trend in adult mortality. Such differences were greater for pupae irradiated at a young age compared those irradiated 24 h before emergence. Our single most relevant finding was that sterility induction (i.e., oviposition of nonfertilized eggs) was two times greater for males irradiated at low doses (40 Gy) than for males irradiated at high doses (80 Gy) when used at a 3:1:1 sterilized male to fertile male to fertile female ratio. Males irradiated at high doses may have been outcompeted by unirradiated males when courting unirradiated females. Implications of our findings for sterile insect technique programs are discussed. PMID:15154459

  15. Post-irradiation stability of polyvinyl chloride at sterilizing doses

    NASA Astrophysics Data System (ADS)

    Naimian, F.; Katbab, A. A.; Nazokdast, H.

    1994-12-01

    Post-irradiation stability of plasticized PVC irradiated by 60Co gamma ray at sterilizing doses has been studied. Effects of irradiation upon chemical structure, mechanical properties and rheological behaviour of samples contained different amounts of Di(2-ethylhexyl)phthalate as plasticizer have been investigated. Formation of conjugated double bonds, carbonyl and hydroxyl groups have been followed by UV and FTIR spectrometers up to 6 months after irradiation. FTIR spectra of irradiated samples showed no significant changes in carbonyl and hydroxyl groups even 6 months after irradiation. However, changes in UV-visible spectra was observed for the irradiated samples up to 6 months post-irradiation. This has been attributed to the formation of polyenes which leads to the discoloration of this polymer. Despite a certain degree of discoloration, it appears that the mechanical properties of PVC are not affected by irradiation at sterilizing doses. No change in the melt viscosity of the irradiated PVC samples with post-irradiation was observed, which is in consistent with the IR results.

  16. Neurite outgrowth on fluorinated polyimide film micropatterned by ion irradiation

    NASA Astrophysics Data System (ADS)

    Okuyama, Y.; Sato, M.; Nagaoka, S.; Kawakami, H.; Suzuki, Y.; Iwaki, M.

    2003-05-01

    In this study, we investigated neurite outgrowth on a fluorinated polyimide film micropatterned by ion irradiation. We used the fluorinated polyimide because of its excellent thermal and mechanical properties and biocompatibility. Rattus norvegicus chromaphin (PC12) cells were used for in vitro studies. The polyimide films were irradiated with He +, Ne + or Kr + at 1 × 10 14 ions/cm 2 using an ion-beam mask. The lines in the mask were 120 and 160 ?m wide and 120-160 ?m apart. PC12 cells were selectively adhered on the polyimide film micropatterned by Kr +-irradiation. However, the neurite length on the film irradiated by Kr + was shorter than that determined in the film irradiated by He +. On the other hand, neurite outgrowth on the polyimide film micropatterned by He +-irradiation was at least 100 ?m in length. This initial study indicated the enhanced outgrowth of PC12 cells on the fluorinated polyimide film micropatterned by ion irradiation.

  17. Irradiation creep and swelling of various austenitic alloys irradiated in PFR and FFTF

    SciTech Connect

    Garner, F.A.; Toloczko, M.B. [Pacific Northwest National Lab., Richland, WA (United States)] [and others

    1996-10-01

    In order to use data from surrogate neutron spectra for fusion applications, it is necessary to analyze the impact of environmental differences on property development. This is of particular importance in the study of irradiation creep and its interactions with void swelling, especially with respect to the difficulty of separation of creep strains from various non-creep strains. As part of an on-going creep data rescue and analysis effort, the current study focuses on comparative irradiations conducted on identical gas-pressurized tubes produced and constructed in the United States from austenitic steels (20% CW 316 and 20% CW D9), but irradiated in either the Prototype Fast Reactor (PFR) in the United Kingdom or the Fast Flux Test Facility in the United States. In PFR, Demountable Subassemblies (DMSA) serving as heat pipes were used without active temperature control. In FFTF the specimens were irradiated with active ({+-}{degrees}5C) temperature control. Whereas the FFTF irradiations involved a series of successive side-by-side irradiation, measurement and reinsertion of the same series of tubes, the PFR experiment utilized simultaneous irradiation at two axial positions in the heat pipe to achieve different fluences at different flux levels. The smaller size of the DMSA also necessitated a separation of the tubes at a given flux level into two groups (low-stress and high-stress) at slightly different axial positions, where the flux between the two groups varied {le}10%. Of particular interest in this study was the potential impact of the two types of separation on the derivation of creep coefficients.

  18. Quantification of biologically effective environmental UV irradiance

    NASA Astrophysics Data System (ADS)

    Horneck, G.

    To determine the impact of environmental UV radiation on human health and ecosystems demands monitoring systems that weight the spectral irradiance according to the biological responses under consideration. In general, there are three different approaches to quantify a biologically effective solar irradiance: (i) weighted spectroradiometry where the biologically weighted radiometric quantities are derived from spectral data by multiplication with an action spectrum of a relevant photobiological reaction, e.g. erythema, DNA damage, skin cancer, reduced productivity of terrestrial plants and aquatic foodweb; (ii) wavelength integrating chemical-based or physical dosimetric systems with spectral sensitivities similar to a biological response curve; and (iii) biological dosimeters that directly weight the incident UV components of sunlight in relation to the effectiveness of the different wavelengths and to interactions between them. Most biological dosimeters, such as bacteria, bacteriophages, or biomolecules, are based on the UV sensitivity of DNA. If precisely characterized, biological dosimeters are applicable as field and personal dosimeters.

  19. Specificity of proton irradiation effects on polymers

    NASA Astrophysics Data System (ADS)

    Briskman, B. A.

    2007-12-01

    Protons affect the polymers mainly through scission and cross-linking of macromolecule chains. Ionization processes at proton non-elastic scattering define these effects. One of the most important problems of radiation physics and chemistry of polymers is the dependence of radiation effects on polymers on the kind of ionizing radiation or the LET problem. Analyze of such dependence for protons and some other kinds of radiation is presented. A detailed examination of 100 MeV proton collisions in polyethyleneterephtalate (PETP, trade mark Mylar) with negligible quantity of additive, on the base of the sample heat conductivity behavior revealed an important role of atomic displacements resulting from elastic nuclear scattering of low energy ions. Such damage of polymer molecules was not obtained for other examined types of radiation, in particular, for recoil nuclei at reactor neutron irradiation and for 60Co ?-irradiation.

  20. EPR study of ?-irradiated cholesteryl methyl carbonate

    NASA Astrophysics Data System (ADS)

    Aras, Erdal; I?lek, Yasemin; Karata?, Ozgul; Abbass, Hind Kh; Birey, Mehmet; Kiliç, Ahmet

    2014-11-01

    The electron paramagnetic resonance (EPR) of ?-irradiated single crystals of cholesteryl methyl carbonate (C29H48O3) has been studied for different orientations of the crystals in a magnetic field. EPR spectra of cholesteryl methyl carbonate (C29H48O3irradiated by 60Co-? were recorded between 125 K and 300 K for different orientations of the crystal in the magnetic field. The spectra were found to be temperature independent. In C29H48O3 single crystal, the radiation damage centers caused by a 60Co-? source were determined as CH?3CH2CH radical. For CH?3CH2CH radical, a value of spectroscopic splitting factor g was calculated and experimentally results were supported by simulation program (WinEPR).

  1. Titanium implants in irradiated dog mandibles

    SciTech Connect

    Schweiger, J.W. (Memorial Sloan-Kettering Cancer Center, New York, NY (USA))

    1989-08-01

    The use of osseointegrated titanium implants has been a great benefit to selected cancer patients who otherwise would not be able to wear conventional and/or maxillofacial prostheses. Cognizant of the risk of osteoradionecrosis, we used an animal model to seek experimental evidence for successful osseointegration in bone irradiated to tumoricidal levels. Five healthy male beagle dogs received 60 gray to a previously edentulated and healed area of the right hemimandible. The left hemimandible was kept as a nonirradiated control. After 9 months, titanium implants were placed and allowed an additional 5 1/2 months to osseointegrate. At that time, block specimens were obtained, radiographed, photographed, and analyzed histologically. Although statistical significance cannot be attached to the results, osseointegration was achieved in half of the irradiated specimens.

  2. Prediction of Irradiation Spectrum Effects in Pyrochlores

    NASA Astrophysics Data System (ADS)

    Uberuaga, B. P.; Jiang, C.; Stanek, C. R.; Sickafus, K. E.; Scott, C.; Smith, R.

    2014-12-01

    The formation energy of cation antisites in pyrochlores (A2B2O7) has been correlated with the susceptibility to amorphize under irradiation, and thus, density functional theory calculations of antisite energetics can provide insights into the radiation tolerance of pyrochlores. Here, we show that the formation energy of antisite pairs in titanate pyrochlores, as opposed to other families of pyrochlores (B = Zr, Hf, or Sn), exhibits a strong dependence on the separation distance between the antisites. Classical molecular dynamics simulations of collision cascades in Er2Ti2O7 show that the average separation of antisite pairs is a function of the primary knock-on atom energy that creates the collision cascades. Together, these results suggest that the radiation tolerance of titanate pyrochlores may be sensitive to the irradiation conditions and might be controllable via the appropriate selection of ion beam parameters.

  3. Irradiation of germanium nanocrystals with reactor neutrons

    NASA Astrophysics Data System (ADS)

    Shlimak, Issai; Levy, Shai; Lu, Tiecheng; Ionov, A. N.

    2012-11-01

    The effect of reactor neutron irradiation on the structure of germanium nanocrystals ion-implanted into an amorphous silicon dioxide film was studied using laser Raman scattering, high-resolution transmission electron microscopy, and X-ray photoelectron spectroscopy. The sample irradiation with a high dose of fast reactor neutrons resulted in lattice destruction and amorphization of a part of nanocrystals, leaving off a significant part well retained. Thus indicating that this nano-based material may have potential for the fabrication of devices operating under extreme conditions. Radiation defect annealing and full restoration of the nanocrystal structure were observed at 800°C; however, the average size of nanocrystals and their spatial distribution were changed.

  4. Atmospheric turbidity determination from irradiance ratios

    SciTech Connect

    Gueymard, C. [Florida Solar Energy Center, Cocoa, FL (United States); Vignola, F. [Univ. of Oregon, Eugene, OR (United States). Physics Dept.

    1997-12-31

    A semi-physical method is proposed to evaluate turbidity from broadband irradiance measurements and other atmospheric parameters. An error analysis and various tests against measured data show that this method can predict accurate turbidities provided that the sky is perfectly cloudless and the diffuse irradiance data are very accurate. Yet, this method is insensitive to errors in input data such as precipitable water and ozone amount. Applications of this method to the quality control of radiation data are discussed. Tests with actual data from Florida and Oregon show good agreement with other methods. Evaluation of the model required a detailed discussion of the accuracy and cosine error of pyranometers, and the uncertainty in precipitable water estimates.

  5. Irradiation effects in simplified nuclear waste glasses

    NASA Astrophysics Data System (ADS)

    Boizot, Bruno; Ollier, Nadège; Olivier, Florent; Petite, Guillaume; Ghaleb, Dominique; Malchukova, Euguenia

    2005-10-01

    The structural evolution of simplified nuclear waste glasses under ?-irradiation (2.5 MeV) has been studied up to cumulated doses of the order of 10 9 Gy. A rapid saturation of the point defect creation is observed at a very low level (in large contrast with what is observed on pure silica). At large doses, we also observe an increase of the polymerization of the vitreous lattice, and the appearance of dissolved molecular oxygen, which however does not coalesce into bubbles. These evolutions can be linked with the diffusion of alkaline ions in the material. The effects of the glass composition (mixed alkali effect, specific role of some particular cations, which are known to block the structural evolution) have been also investigated in order to study the possibility of decreasing alkaline mobility under irradiation.

  6. Precipitation during irradiation: an experimental example

    SciTech Connect

    Gelles, D.S.

    1981-01-01

    Neutron damage can significantly alter the process of precipitation from supersaturated solid solution. This is demonstrated by a series of experiments using a precipitation strengthened superalloy, Nimonic PE16 irradiated with fast neutrons over the temperature 400 to 650/sup 0/C. In disagreement with earlier predictions, precipitate development is found to be controlled by the competing processes of Ostwald coarsening and solute segregation due to drag by point defects to point defect sinks. Analysis of the kinetics of Ostwald coarsening reveals significant enhancement of diffusion rates due to irradiation in agreement with predictions and involving an activation energy on the order of one quarter that of thermal diffusion. Unusual precipitate morphologies were observed such as void shells, linear precipitate arrays and Archimedes' screw configurations. However, predicted temperature dependencies for solute segregation are not obeyed.

  7. Precipitation during irradiation: an experimental example

    SciTech Connect

    Gelles, D.S.

    1981-01-01

    Neutron damage can significantly alter the process of precipitation from supersaturated solid solution. This is demonstrated by a series of experiments using a precipitation strengthened superalloy, Nimonic PE16 irradiated with fast neutrons over the temperature 400 to 650/sup 0/C. In disagreement with earlier predictions, precipitate development is found to be controlled by the competing processes of Ostwald coarsening and solute segregation due to drag by point defects to point defect sinks. Analysis of the kinetics of Ostwald coarsening reveals significant enhancement of diffusion rates due to irradiation in agreement with predictions and involving an activation energy on the order of one quarter that of thermal diffusion. Unusual precipitate morphologies were observed such as void shells, linear precipitate arrays and Archimedes' screw configurations. However, predicted temperature dependencies for solute segregation are not obeyed. An explanation is presented involving the coupling of the Ostwald coarsening mechanism with the solute segregation process.

  8. UVA system for human cornea irradiation

    NASA Astrophysics Data System (ADS)

    Pereira, Fernando R. A.; Stefani, Mario; Otoboni, José A.; Richter, Eduardo H.; Rossi, Giuliano; Mota, Alessandro D.; Ventura, Liliane

    2009-02-01

    According to recent studies, an increase in corneal stiffness is a promising alternative for avoiding ectasias and for stagnating keratoconus of grades 1 and 2. The clinical treatment consists essentially of instilling Riboflavin (vitamin B2), in the cornea and then irradiating the corneal tissue, with UVA (365nm) radiation at 3mW/cm2 for 30min. This procedure provides collagen cross-linking in the corneal surface, increasing its stiffness. This work presents a system for UVA irradiation of the corneas at a peak wavelength of 365nm with adjustable power up to 5mW. The system has closed loop electronics to control the emitted power with 20% precision from the sated power output. The system is a prototype for performing corneal cross-linking and has been clinically tested. The closed loop electronics is a differential from the equipments available on the market.

  9. Development of microstructural features during irradiation

    SciTech Connect

    Wiedersich, H.

    1980-01-01

    During elevated temperature irradiation with energetic neutrons, ions or electrons, the microstructure of alloys undergoes significant changes accompanied by corresponding changes in physical properties. The microstructural development is caused by the defect production throughout the material and the concurrent annihilation of the mobile point defects and small defect clusters on spatially discrete sinks such as dislocations, grain boundaries and voids. We review here the present understanding of the development of the radiation microstructure beyond the nucleation stage of stable defect clusters. After a short characterization of the dynamic state of a crystalline material during elevated temperature irradiation we discuss (a) the void swelling phenomenon; (b) radiation-enhanced, diffusion controlled processes such as precipitate coarsening; and (c) radiation-induced processes such as radiation-induced precipitation and spatial redistribution of phases in multiphase alloys.

  10. TEM study of neutron-irradiated iron

    SciTech Connect

    Horton, L.L.; Bentley, J.; Farrell, K.

    1981-01-01

    Results of a transmission electron microscopy study of the defect structure in iron neutron-irradiated to low fluences (less than or equal to 1 dpa) at temperatures of 455 to 1013/sup 0/K are presented. The dislocation microstructures coarsen with increasing irradiation temperature from decorated dislocations, through clusters of dislocation loops, to near-edge, interstitial dislocation loops with b = a<100>, and network segments. Significant cavity formation occurred only at 548 to 723/sup 0/K, with homogeneous distributions found only at 623 and 673/sup 0/K. The maximum swelling of 0.07% occurred at 673/sup 0/K. Large cavities had a truncated octahedral shape with (111) facets and (100) truncations. Damage halos were observed around boron-containing precipitates. The effects of interstitial impurities on microstructural development and the differences in the observed microstructures compared to those in refractory bcc metals are discussed. 8 figures, 6 tables.

  11. Survival after total body irradiation: Effects of irradiation of exteriorized small intestine. (Reannouncement with new availability information)

    SciTech Connect

    Vriesendorp, H.M.; Vigneulle, R.M.; Kitto, G.; Pelky, T.; Taylor, P.

    1993-12-31

    Rats receiving lethal irradiation to their exteriorized small intestine with pulsed 18 MVp bremsstrahlung radiation live about 4 days longer than rats receiving a dose of total-body irradiation (TBI) causing intestinal death. The LD50 for intestinal irradiation is approximately 6 Gy higher than the LD50 for intestinal death after TBI. Survival time after exteriorized intestinal irradiation can be decreased, by adding abdominal irradiation. Adding thoracic or pelvic irradiation does not alter survival time. Shielding of large intestine improves survival after irradiation of the rest of the abdomen while the small intestine is also shielded. The kinetics of histological changes in small intestinal tissues implicate the release of humoral factors after irradiation of the abdomen. Radiation injury develops faster in the first (proximal) 40 cm of the small intestine and is expressed predominantly as shortening in villus height. In the last (distal) 40 cm of the small intestine, the most pronounced radiation effect is a decrease in the number of crypts per millimeter. Irradiation (20 Gy) of the proximal small intestine causes 92 % mortality (median survival 10 days). Irradiation (20 Gy) of the distal small intestine causes 27% mortality (median survival > 30 days). In addition to depletion of crypt stem cells in the small intestine, other issues (humoral factors, irradiated subsection of the small intestine and shielding of the large intestine) appear to influence radiation-induced intestinal mortality.

  12. Cutaneous Angiosarcoma Arising in an Irradiated Breast

    Microsoft Academic Search

    Carlo Tomasini; Marcella Grassi; Mario Pippione

    2004-01-01

    Angiosarcoma (AS) is a rare, aggressive tumour of endothelial origin occurring in various clinical settings, including idiopathic AS on the head and neck in elderly people, lymphoedema-associated AS, post-irradiation AS, soft-tissue AS, and various others. Despite the widespread use of radiation therapy in the treatment of breast carcinoma, AS developing in the wake of a radiation therapy is extremely infrequent.

  13. [Stereotactic irradiation in head and neck cancers].

    PubMed

    Benhaïm, C; Lapeyre, M; Thariat, J

    2014-01-01

    Stereotactic radiotherapy is increasingly used in head and neck tumours, either as a boost for dose escalation/early salvage, or in the reirradiation setting. We aimed to assess the level of evidence for each clinical setting and to discuss the different dose and frationation regimens. A search of the French and English literature was performed on PubMed until December 2013. Stereotactic reirradiation of locally recurrent squamous cell carcinomas can be performed with overall survival rates of about 12 months with good quality of life, and acceptable toxicity, based on several phase 2 trials and retrospective studies. Nasopharyngeal carcinomas may be irradiated with even better control rates. Late severe toxicities yield up to 20-30%. Patient and tumour selection criteria (limited volume) and dose constraints to the carotids (cumulative dose 110 Gy or less, to avoid the risk of potentially lethal carotid blowout) must be carefully chosen. Fractionated regimens (at least five fractions) should be preferred (30 Gy in five fractions to 36 Gy in six fractions). Methods derived from stereotactic, intensity-modulated radiotherapy (IMRT) may be used with conventional fractionation for larger tumours. Stereotactic irradiation may be associated with cetuximab; data with chemotherapy or other targeted therapies are still lacking. Stereotactic irradiation is also used as a boost after 46 Gy IMRT in several institutions or for early salvage (8 to 10 weeks following full dose irradiation with evidence of residual tumour) in squamous or nasopharyngeal carcinomas. Such indications should be evaluated prospectively in clinical trials. Data in salivary gland and sinonasal neoplasms are still scarce. In conclusion, stereotactic body radiation therapy has the potential as a boost or in the reirradiation setting to improve local control in head and neck tumours. Careful hypofractionation with planning caring for the dose to the main vessels is highly recommended. Prospective studies with prolonged follow-up (at least 2 years) should be encouraged. PMID:25059767

  14. Post irradiation examination of thermal reactor fuels

    NASA Astrophysics Data System (ADS)

    Sah, D. N.; Viswanathan, U. K.; Ramadasan, E.; Unnikrishnan, K.; Anantharaman, S.

    2008-12-01

    The post irradiation examination (PIE) facility at the Bhabha Atomic Research Centre (BARC) has been in operation for more than three decades. Over these years this facility has been utilized for examination of experimental fuel pins and fuels from commercial power reactors operating in India. In a program to assess the performance of (U,Pu)O 2 MOX fuel prior to its introduction in commercial reactors, three experimental MOX fuel clusters irradiated in the pressurized water loop (PWL) of CIRUS up to burnup of 16 000 MWd/tU were examined. Fission gas release from these pins was measured by puncture test. Some of these fuel pins in the cluster contained controlled porosity pellets, low temperature sintered (LTS) pellets, large grain size pellets and annular pellets. PIE has also been carried out on natural UO 2 fuel bundles from Indian PHWRs, which included two high burnup (˜15 000 MWd/tU) bundles. Salient investigations carried out consisted of visual examination, leak testing, axial gamma scanning, fission gas analysis, microstructural examination of fuel and cladding, ?, ? autoradiography of the fuel cross-section and fuel central temperature estimation from restructuring. A ThO 2 fuel bundle irradiated in Kakrapar Atomic Power Station (KAPS) up to a nominal fuel burnup of ˜11 000 MWd/tTh was also examined to evaluate its in-pile performance. The performance of the BWR fuel pins of Tarapur Atomic Power Stations (TAPS) was earlier assessed by carrying out PIE on 18 fuel elements selected from eight fuel assemblies irradiated in the two reactors. The burnup of these fuel elements varied from 5000 to 29 000 MWd/tU. This paper provides a brief review of some of the fuels examined and the results obtained on the performance of natural UO 2, enriched UO 2, MOX, and ThO 2 fuels.

  15. Total lymphoid irradiation for multiple sclerosis

    SciTech Connect

    Devereux, C.K.; Vidaver, R.; Hafstein, M.P.; Zito, G.; Troiano, R.; Dowling, P.C.; Cook, S.D.

    1988-01-01

    Although chemical immunosuppression has been shown to benefit patients with chronic progressive multiple sclerosis (MS), it appears that chemotherapy has an appreciable oncogenic potential in patients with multiple sclerosis. Accordingly, we developed a modified total lymphoid irradiation (TLI) regimen designed to reduce toxicity and applied it to a randomized double blind trial of TLI or sham irradiation in MS. Standard TLI regimens were modified to reduce dose to 1,980 rad, lowering the superior mantle margin to midway between the thyroid cartilage and angle of the mandible (to avert xerostomia) and the lower margin of the mantle field to the inferior margin of L1 (to reduce gastrointestinal toxicity by dividing abdominal radiation between mantle and inverted Y), limiting spinal cord dose to 1,000 rad by custom-made spine blocks in the mantle and upper 2 cm of inverted Y fields, and also protecting the left kidney even if part of the spleen were shielded. Clinical efficacy was documented by the less frequent functional scale deterioration of 20 TLI treated patients with chronic progressive MS compared to to 20 sham-irradiated progressive MS patients after 12 months (16% versus 55%, p less than 0.03), 18 months (28% versus 63%, p less than 0.03), and 24 months (44% versus 74%, N.S.). Therapeutic benefit during 3 years follow-up was related to the reduction in lymphocyte count 3 months post-irradiation (p less than 0.02). Toxicity was generally mild and transient, with no instance of xerostomia, pericarditis, herpes zoster, or need to terminate treatment in TLI patients. However, menopause was induced in 2 patients and staphylococcal pneumonia in one.

  16. Spallation of metals under laser irradiation

    Microsoft Academic Search

    V. E. Fortov; V. V. Kostin; S. Eliezer

    1991-01-01

    Laser-driven shock-wave loading enables the study of ultrahigh strain rates (107 s?1). A damage model for the spallation process has been included in a two-dimensional finite-difference hydrodynamic elastoplastic code using Lagrangian coordinates in order to calculate the laser-induced spall phenomena. The damage was investigated using shock waves induced by a short-pulsed laser in copper and aluminum foils. Laser irradiation intensities

  17. Metal fuel manufacturing and irradiation performance

    SciTech Connect

    Pedersen, D.R.; Walters, L.C.

    1992-06-01

    The advances in metal fuel by the Integral Fast Reactor Program at Argonne National Laboratory are the subject of this paper. The Integral Fast Reactor (IFR) is an advanced liquid-metal-cooled reactor concept being developed at Argonne National Laboratory. The advances stressed in the paper include fuel irradiation performance, and improved passive safety. The goals and the safety philosophy of the Integral Fast Reactor Program are stressed.

  18. Lymphocyte pyknosis following cobalt - 60 gamma irradiation

    E-print Network

    Lane, Linda Kay

    1971-01-01

    Major Subject: Biophysics (Health Physics) LYMPHOCYTE PYKNOSIS FOLLOWING COBALT ? 60 GAMMA IRRADIATION A Thesis by LINDA KAY LANE Approved as to style and content by: (C airman of Co tee) z MzD'P, ; (Head 'of Department) (Member) (Member...' lymphoid cells. Thus, the response of lymphocytes to a general stimulus (indirect), the action on individual cells causing their removal (direct), or a combination of the above effects may be possible reasons for the rapid de- crease in circulating...

  19. Models of Irradiated Extrasolar Giant Planets

    E-print Network

    Adam Burrows; David Sudarsky

    2002-07-23

    We review some of the characteristics of irradiated extrasolar giant planets (EGPs), in anticipation of their direct detection from the ground and from space. Spectral measurements are the key to unlocking their structural and atmospheric characteristics and to determining the true differences between giant planets and brown dwarfs. In this spirit, the theoretical spectral and atmospheric calculations we summarize here are in support of the many searches for EGPs to be conducted in the coming decade by astronomers from around the world.

  20. Spectral Irradiance Measurements Based on Detector

    NASA Astrophysics Data System (ADS)

    Lima, M. S.; Menegotto, T.; Duarte, I.; Ferreira da Silva, T.; Alves, L. C.; Alvarenga, A. D.; Almeida, G. B.; Teixeira, R. N.; Couceiro, I. B.

    2015-01-01

    This paper presents the preliminary results of the realization of absolute spectral irradiance scale at INMETRO in the ultraviolet, visible and infrared regions using filter radiometers as secondary standards. In the construction of these instruments are used, at least, apertures, interference filters and a trap detector. In the assembly of the trap detectors it was necessary to characterize several photocells in spatial uniformity and shunt resistance. All components were calibrated and these results were analyzed to mount the filter radiometer.

  1. The puridec range of gamma irradiation plants

    Microsoft Academic Search

    G. W. Reuter

    1995-01-01

    In 1992 Amersham International plc. and NUKEM GmbH agreed to cooperate in the field of industrial gamma irradiation plants. Consequently the brand “PURIDEC” was founded, to handle the common business worldwide.Amersham Int. plc. has been a leading company in manufacturing and transport of Co60 sources for more than 30 years while NUKEM looks back to three decades of experience in

  2. Radiobiological speculations on therapeutic total body irradiation

    Microsoft Academic Search

    H. M. Vriesendorp

    1990-01-01

    Unexpected total body irradiation (TBI) of human beings, involved in nuclear warfare or in accidents in nuclear reactors can be lethal. In the 1950s, bone marrow transplantation was discovered as a potentially life saving procedure after TBI in the dose range of 5.0 to 12.0 Gy. Since that time, deliberate or therapeutic TBI has been used to condition patients with

  3. Protein Quality of Irradiated Brazilian Beans

    NASA Astrophysics Data System (ADS)

    Delincée, Henry; Villavicencio, Anna-Lucia C. H.; Mancini-Filho, Jorge

    1998-06-01

    Beans are a major source of dietary protein in Brazil. However, high losses due to insect infestation occur after each harvest. To combat these losses, radiation processing of beans offers promise as an alternative to chemical treatment, provided the nutritional quality of beans is not impaired by the radiation treatment. Conflicting results have been published about the effect of radiation on the biological value of legume proteins. Therefore, two varieties of Brazilian beans were studied: 1) Phaseolus vulgaris L., var. carioca and 2) Vigna unguiculata (L.) Walp, var. macaçar. The beans were irradiated with doses of 0, 0.5, 1.0, 2.5, 5.0 and 10 kGy. Since irradiated beans will be consumed after appropriate storage, the beans under study were stored for 6 months at ambient temperature. Protein quality was measured by a biological assay employing the nitrogen balance approach in weanling rats. The animals were fed with optimally cooked beans, which were the only source of protein (˜10%). Nitrogen contents of legumes, diets, animal urine and faeces were determined by Kjeldahl analysis. The indices for apparent protein quality: net protein utilisation, digestibility and biological value were not influenced by irradiation. Thus, radiation treatment of Brazilian beans offers considerable promise as an effective insect disinfection process, without impairing the biological quality of the valuable bean protein.

  4. Irradiation effects on polymer-model compounds

    NASA Astrophysics Data System (ADS)

    Seguchi, Tadao; Katsumura, Yosuke; Hayashi, Nariyuki; Hayakawa, Naohiro; Tamura, Naoyuki; Tabata, Yoneho

    Irradiation effects on n-paraffins and squalane, used as models of polymers, were investigated by product analysis. Four n-paraffins, C 20H 42, C 21H 44, C 23H 48 and C 24H 50, and squalane (C 30H 62) were ?-irradiated under vacuum in liquid, crystalline and glassy states. The evolved gases were analyzed by gas chromatography and changes in molecular weight were analyzed by liquid chromatography and mass spectroscopy. G-values for crosslinking of n-paraffins were 1.2 for crystalline states (at 25°C) and 1.7 for liquid states (at 55°C), and showed no difference between odd and even carbon numbers. The G-value of liquid squalane was 1.7; it was 1.3 for the glassy state at low temperature (-77°C). Double bonds were common in the crosslinked products, especially after liquid-phase irradiation. The probability of chain scission was estimated as being negligible, though a small number of chain-scission products (which were products of scission at chain-ends or side chains) were observed by gas analysis.

  5. Dosimetry of biological irradiations using radiochromic films.

    PubMed

    Aldelaijan, S; Nobah, A; Alsbeih, G; Moftah, B; Aldahlawi, I; Alzahrany, A; Tomic, N; Devic, S

    2013-05-21

    Delivering accurate radiation dose to blood specimens during biological irradiations is essential in quantifying damage of ionizing radiation. To estimate dose to blood samples as accurately as possible, pieces of EBT2 model GAFCHROMIC™ film were placed within an approximately 10 mm finely ground rice layer that was used to simulate test specimens inside 40 mL plastic flasks. Irradiations of flasks were carried out using an X-RAD 320 irradiator with a beam quality of 320 kVp and a measured half value layer of 1.12 mm Cu, in air and in a full scattering setup which consisted of either rice or Solid Water™ (SW) surrounding flasks, filled to the same level at top of the flasks, together with a 5 cm thick SW slab beneath them. Outputs, per cent depth doses and beam profiles at different depths were measured and compared between setups. For the same setting, the dose delivered to the middle flask under the full scattering setup is 22% larger than with the in-air setup at the depth of the specimen and 9.2% more homogeneous across the specimen thickness of 10 mm (2.3% variation in comparison to the surface). Rice showed a fairly similar performance to SW within 1% at the same depth of 10 mm. Experimental setup based on full scattering conditions was shown to provide faster, more homogenous and fairly uniform dose delivery to biological specimens in comparison to conventionally used in-air setups. PMID:23603810

  6. Irradiation response and stability of nanoporous materials

    SciTech Connect

    Fu, Engang [Los Alamos National Laboratory; Wang, Yongqiang [Los Alamos National Laboratory; Serrano De Caro, Magdalena [Los Alamos National Laboratory; Caro, Jose A. [Los Alamos National Laboratory; Zepeda-Ruiz, L [Lawrence Livermore national Laboratory; Bringa, E. [CONICET, Universidad de Cuyo, Argentina; Nastasi, Mike [University of Nebraska, Lincoln, NE; Baldwin, Jon K. [Los Alamos National Laboratory

    2012-08-28

    Nanoporous materials consist of a regular organic or inorganic framework supporting a regular, porous structure. Pores are by definition roughly in the nanometre range, that is between 0.2 nm and 100 nm. Nanoporous materials can be subdivided into 3 categories (IUPAC): (1) Microporous materials - 0.2-2 nm; (2) Mesoporous materials - 2-50 nm; and (3) Macroporous materials - 50-1000 nm. np-Au foams were successfully synthesized by de-alloying process. np-Au foams remain porous structure after Ne ion irradiation to 1 dpa. Stacking Fault Tetrahedra (SFTs) were observed in RT irradiated np-Au foams under the highest and intermediate fluxes, but not under the lowest flux. SFTs were not observed in LNT irradiated np-Au foams under all fluxes. The vacancy diffusivity in Au at RT is high enough so that the vacancies have enough time to agglomerate and then collapse to form SFTs. The high ion flux creates more damage per unit time; vacancies don't have enough time to diffuse or recombine. As a result, SFTs were formed at high ion fluxes.

  7. NOTE: Validation of blood product irradiation doses

    NASA Astrophysics Data System (ADS)

    Cheung, T.; Butson, M.; Yu, P. K. N.

    2001-10-01

    Dosimetry of blood irradiation using x-ray beams on a medical linear accelerator has been studied to evaluate the accuracy of a diode detector and the delivery achievable. Variations in applied doses for a standard dual field 6 MV x-ray are measured with a commercial diode detector. Results show that the diode detector measured applied in vitro doses to within 5.4% (2 standard deviations (2 SD)) of those calculated with a collapsed-cone convolution treatment-planning computer for a sample of 100 blood irradiations. Experiments involving the packing procedure of the blood products in the blood box were performed. It was found that a large proportion of the variation in the predicted and measured dose was due to the compacting of the scatter material at the base of the blood box (over a 6 month period) producing a higher density below the blood than originally scanned; hence an overall reduction of delivered dose was observed. The diode measurements (which provide an immediate printout) are recommended in conjunction with a film dosimeter such as radiochromic film, which still provides a back-up dose monitor and a visual reminder that the blood has been irradiated. It is also recommended that the blood box be completely evacuated of all scatter material every month and the base be carefully repacked to provide uniform scatter material.

  8. Irradiation Products On Dwarf Planet Makemake

    NASA Astrophysics Data System (ADS)

    Brown, M. E.; Schaller, E. L.; Blake, G. A.

    2015-03-01

    The dark, reddish tinged surfaces of icy bodies in the outer solar system are usually attributed to the long term irradiation of simple hydrocarbons leading to the breaking of C–H bonds, loss of hydrogen, and the production of long carbon chains. While the simple hydrocarbon methane is stable and detected on the most massive bodies in the Kuiper Belt, evidence of active irradiation chemistry is scant except for the presence of ethane on methane-rich Makemake and the possible detections of ethane on more methane-poor Pluto and Quaoar. We have obtained deep high signal-to-noise spectra of Makemake from 1.4 to 2.5 ?m in an attempt to trace the radiation chemistry in the outer solar system beyond the initial ethane formation. We present the first astrophysical detection of solid ethylene and evidence for acetylene and high-mass alkanes—all expected products of the continued irradiation of methane, and use these species to map the chemical pathway from methane to long-chain hydrocarbons.

  9. Advanced lymphosarcoma treated by total body irradiation.

    PubMed Central

    Chaffey, J. T.; Rosenthal, D. S.; Pinkus, F.; Hellman, S.

    1975-01-01

    Twenty-five cases of clinical Stage III and Stage IV lymphosarcoma primarily treated by total body irradiation (TBI) are reported. Fifteen cases demonstrated nodular histology and 10 demonstrated diffuse histology by the Rappaport criteria. Treatments were 15 rad given twice weekly, calculated to midpelvis, to a total dose of 150 rad. Toxicity was confined to thrombocytopenia, one-third of patients requiring interruptions in the treatment course to allow platelet count recovery. Five patients had additional local irradiation. Complete responses were seen in 80% of patients and partial responses in 20%. Sixteen patients (64%) have been in continuous, unmaintained remission since treatments for variable periods to 39 months. Of 9 patients with clinically recurrent disease, 3 received further TBI and are in remission, 3 are in remission on chemotherapy, one patient has died, failing on all therapy, and 2 have not been treated. One patient died of pneumonia at 12 months, without clinical evidence of disease. Overall, actuarial survival is 87% at 2 years and compares well with survival in a sequential combination drug treated group of patients matched for age, sex, and histology, though differences are not statistically significant in these small groups. Total body irradiation is an effective systemic agent in the management of advanced lymphosarcoma and should be considered in treating this disease. PMID:810155

  10. Estimating probability distributions of solar irradiance

    NASA Astrophysics Data System (ADS)

    Voskrebenzev, A.; Riechelmann, S.; Bais, A.; Slaper, H.; Seckmeyer, G.

    2015-02-01

    In the presence of clouds the ability to calculate instantaneous spectral irradiance values is limited by the ability to acquire appropriate input parameters for radiative transfer solvers. However, the knowledge of the statistical characteristics of spectral irradiance as a function of season and time of the day is relevant for solar energy and health applications. For this purpose a method to derive the wavelength dependent probability density functions (PDFs) and its seasonal site variability is presented. In contrast to the UVB range, the derived PDFS at three stations in Europe (Bilthoven, Garmisch-Partenkirchen and Thessaloniki) show only minor wavelength dependence above 315 nm. But there are major differences of the PDFs that are attributed to the site specific cloud climatology at these stations. Furthermore the results suggest that the previously described relationship between air mass and bimodality is the consequence of seasonal cloud variations. For Thessaloniki it is shown that the pyranometer sample spread around the cloudless value is proportional to the secant of the solar zenith angle and therefore scales according to air mass. Cloud amount observations are utilized to associate the local maxima of the multimodal PDFs with rough cloudiness states confirming the already established interpretation of broadband data for spectral data as well. As one application example the likelihood of irradiance enhancements over the clear sky case due to clouds is assessed.

  11. Proton irradiation of various resistivity silicon detectors

    SciTech Connect

    Bates, S.J.; Dezillie, B.; Furetta, C.; Glaser, M.; Lemeilleur, F. [CERN, Geneva (Switzerland)] [CERN, Geneva (Switzerland); Leon-Florian, E. [Univ. de Montreal, Quebec (Canada)] [Univ. de Montreal, Quebec (Canada)

    1996-06-01

    Future high energy physics experiments at CERN`s Large Hadron Collider will use high precision silicon detectors for tracking purposes. The hadronic component of the radiation received threatens the lifetime of these detectors and it is vital to choose the silicon starting material to maximize the performance and lifetime. Ion-implanted silicon detectors with various initial resistivities and germanium concentrations have been irradiated with high energy protons up to a fluence of 10{sup 14} cm{sup {minus}2}. The change in leakage current and full depletion voltage have been studied both as a function of fluence and of time after irradiation. Measurements were made up to 100 days post-irradiation at room temperature and then using heating techniques to accelerate processes up to the equivalent of over 10 years at room temperature. The leakage-current damage constant is shown to be independent of the starting material while the conduction type inversion point and the long-term annealing of the depletion voltage are sensitive to the initial resistivity and impurity concentrations.

  12. Electron beam irradiation of fluoropolymers containing polyethers

    NASA Astrophysics Data System (ADS)

    Bucio, E.; Burillo, G.; Tapia, F.; Adem, E.; Cedillo, G.; Cassidy, P. E.

    2009-02-01

    A highly fluorinated monomer, 1,3-bis(1,1,1,3,3,3-hexafluoro-2-pentafluorophenyl methoxy-2-propyl)benzene (12F-FBE) was polymerized with some diphenols by polycondensation and then was electron beam irradiated between 100 and 1000 kGy to determine degradation radiochemistry yield ( Gs) by gel permeation chromatography (GPC). The samples were characterized after irradiation by DSC, FTIR, and nuclear magnetic resonance (NMR). The fluoropolymers show apparent degradation in mechanical properties at 300 kGy, except 12F-FBE polymerized with biphenol and bisphenol A, when they did not show any apparent physical change up to 300 kGy; and continue to be flexible and transparent, with a radiochemical yield scission ( Gs) of 0.75, 0.53, 0.88, and 0.38 for 12F-FBE/SDL aliphatic, 12F-FBE/biphenol, 12F-FBE/bisphenol A, and 12F-FBE/bisphenol O, respectively. The number average molecular weights for three of the polymers decrease upon 1000 kGy irradiation to 10% of their original values; however, the polymer from bisphenol A is much more stable and its Mn decreases to only 24% of original.

  13. Hodgkin's disease: thyroid dysfunction following external irradiation

    SciTech Connect

    Tamura, K.; Shimaoka, K.

    1981-01-01

    The thyroid gland is commonly included in the field of radiation therapy for patients with malignant lymphoma and with head and neck tumors. The radiation dose for malignant diseases varies considerably depending on the purpose of treatment and the institutional policies. A substantial number of these patients are developing subclinical and clinical hypothyroidism. The risk of developing hypothyroidism after a moderate radiation dose of 2000 to 4500 rads has been reported to be 10 to 20 percent. In addition, subclinical hypothyroidism is induced further in one third of the patients. There are also suggestions that external irradiation of the thyroid gland in patients with malignant lymphomas, as well as internal irradiation with radioiodine of the normal and hyperthyroid human thyroid glands, would induce elevations of serum antithyroid autoantibody titers. However, only a few cases of Graves disease following irradiation to the thyroid gland have been reported. We encountered a young woman who received radiation therapy to the mantle field for her Hodgkin's disease and developed hypothyroxinemia without overt signs and symptoms of hypothyroidism, followed by appearance of nodular goiter and then full-blown Graves disease.

  14. Irradiation growth of zirconium single crystals

    NASA Astrophysics Data System (ADS)

    Carpenter, G. J. C.; Murgatroyd, R. A.; Rogerson, A.; Watters, J. F.

    1981-10-01

    Irradiation growth of zirconium single crystals has been studied during neutron irradiation at 353 K and 553 K at fluences up to 2× 10 25 n/m 2. The results may be summarized as follows: (a) there was an expansion parallel to the a-axis and a c-axis contraction; (b) the growth strains were small (~10 -4), (c) growth saturated at fluences less than ~5× 10 24 n/m 2, (d) the growth behaviour was only weakly dependent on temperature for the range studied, (e) there was a calculated volume increase of the same order as the growth strain, and (f) single crystals prepared from stock of iodide and zone-refined purity showed similar growth behaviour at 553 K. The a-axis expansion is attributed to the annihilation of an excess of interstitials at < a>-type dislocations and interstitial loops. The c-axis contraction may be caused by: (1) elastic relaxation around vacancies or small vacancy clusters, (2) non-linear elastic effects at the dislocation cores of small < a>-type loops, or (3) sub-microscopic vacancy loops with < c>-component Burgers vectors. Comparison with data from polycrystalline zirconium confirms that grain boundaries can play an important role in the irradiation growth of zirconium.

  15. Local brain heavy ion irradiation induced Immunosuppression

    NASA Astrophysics Data System (ADS)

    Lei, Runhong; Deng, Yulin; Huiyang Zhu, Bitlife.; Zhao, Tuo; Wang, Hailong; Yu, Yingqi; Ma, Hong; Wang, Xiao; Zhuang, Fengyuan; Qing, Hong

    Purpose: To investigate the long term effect of acute local brain heavy ion irradiation on the peripheral immune system in rat model. Methodology: Only the brain of adult male Wistar rats were radiated by heavy ions at the dose of 15 Gy. One, two and three months after irradiation, thymus and spleen were analyzed by four ways. Tunel assay was performed to evaluate the percentage of apoptotic cells in thymus and spleen, level of Inflammatory cytokines (IL-2, IL-6, SSAO, and TNF-?) was detected by ELISA assay, the differentiation of thymus T lymphocyte subsets were measured by flow cytometry and the relative expression levels of genes related to thymus immune cell development were measured by using quantitative real-time PCR. Results: Thymus and spleen showed significant atrophy from one month to three months after irradiation. A high level of apoptosis in thymus and spleen were obtained and the latter was more vulnerable, also, high level of inflammatory cytokines were found. Genes (c-kit, Rag1, Rag2 and Sca1) related to thymus lymphocytes’ development were down-regulated. Conclusion: Local area radiation in the rat brain would cause the immunosuppression, especially, the losing of cell-mediated immune functions. In this model, radiation caused inflammation and then induced apoptosis of cells in the immune organs, which contributed to immunosuppression.

  16. Total scalp irradiation using helical tomotherapy

    SciTech Connect

    Orton, Nigel [Department of Human Oncology, University of Wisconsin, Madison, WI (United States)]. E-mail: nporton@facstaff.wisc.edu; Jaradat, Hazim [Department of Human Oncology, University of Wisconsin, Madison, WI (United States); Welsh, James [Department of Human Oncology, University of Wisconsin, Madison, WI (United States); Tome, Wolfgang [Department of Human Oncology, University of Wisconsin, Madison, WI (United States); Department of Medical Physics, University of Wisconsin, Madison, WI (United States)

    2005-09-30

    Homogeneous irradiation of the scalp poses technical and dosimetric challenges due to the extensive, superficial, curved treatment volume. Conventional treatments on a linear accelerator use multiple matched electron fields or a combination of electron and photon fields. Problems with these techniques include dose heterogeneity in the target due to varying source-to-skin distance (SSD) and angle of beam incidence, significant dose to the brain, and the potential for overdose or underdose at match lines between the fields. Linac-based intensity-modulated radiation therapy (IMRT) plans have similar problems. This work presents treatment plans for total scalp irradiation on a helical tomotherapy machine. Helical tomotherapy is well-suited for scalp irradiation because it has the ability to deliver beamlets that are tangential to the scalp at all points. Helical tomotherapy also avoids problems associated with field matching and use of more than one modality. Tomotherapy treatment plans were generated and are compared to plans for treatment of the same patient on a linac. The resulting tomotherapy plans show more homogeneous target dose and improved critical structure dose when compared to state-of-the-art linac techniques. Target equivalent uniform dose (EUD) for the best tomotherapy plan was slightly higher than for the linac plan, while the volume of brain tissue receiving over 30 Gy was reduced by two thirds. Furthermore, the tomotherapy plan can be more reliably delivered than linac treatments, because the patient is aligned prior to each treatment based on megavoltage computed tomography (MVCT)

  17. Dosimetry of biological irradiations using radiochromic films

    NASA Astrophysics Data System (ADS)

    Aldelaijan, S.; Nobah, A.; Alsbeih, G.; Moftah, B.; Aldahlawi, I.; Alzahrany, A.; Tomic, N.; Devic, S.

    2013-05-01

    Delivering accurate radiation dose to blood specimens during biological irradiations is essential in quantifying damage of ionizing radiation. To estimate dose to blood samples as accurately as possible, pieces of EBT2 model GAFCHROMIC™ film were placed within an approximately 10 mm finely ground rice layer that was used to simulate test specimens inside 40 mL plastic flasks. Irradiations of flasks were carried out using an X-RAD 320 irradiator with a beam quality of 320 kVp and a measured half value layer of 1.12 mm Cu, in air and in a full scattering setup which consisted of either rice or Solid Water™ (SW) surrounding flasks, filled to the same level at top of the flasks, together with a 5 cm thick SW slab beneath them. Outputs, per cent depth doses and beam profiles at different depths were measured and compared between setups. For the same setting, the dose delivered to the middle flask under the full scattering setup is 22% larger than with the in-air setup at the depth of the specimen and 9.2% more homogeneous across the specimen thickness of 10 mm (2.3% variation in comparison to the surface). Rice showed a fairly similar performance to SW within 1% at the same depth of 10 mm. Experimental setup based on full scattering conditions was shown to provide faster, more homogenous and fairly uniform dose delivery to biological specimens in comparison to conventionally used in-air setups.

  18. Evaporation of solids by pulsed laser irradiation

    NASA Astrophysics Data System (ADS)

    Stafast, H.; Von Przychowski, M.

    The focused beam of a KrF laser (248 nm) has been applied to irradiate targets of Al 2O 3, SiC, graphite, Pb, Ni, Cr, quartz, and NaCl at variable laser energy flux is the range 0-13 J/cm 2. The amount of target material ejected into the vacuum (background pressure about 8 × 10 -4 Torr) was determined from the target weight before and after laser irradiation. The average number of particles (formula weight) evaporated per laser pulse and per unit of irradiated target area is non-linearly dependent on the laser energy flux. The evaporation of Al 2O 3, SiC, and graphite is showing a well-defined flux threshold while the vaporization of Pb, Ni and Cr is rising smoothly with increasing flux. With both groups of materials laser evaporation is monotonically increasing with the laser energy flux. NaCl and quartz, on the other hand, are showing an intermediate maximum in the laser vaporization efficiency.

  19. Industrial irradiator radiation safety program assessments

    NASA Astrophysics Data System (ADS)

    Smith, Mark A.

    2000-03-01

    Considerable attention is typically given to radiation safety in the design of irradiators and initially establishing the program. However, one component that may not receive enough attention is applying the continuous improvement philosophy to the radiation safety program. Periodic total program assessments of radiation safety can ensure that the design and implementation of the program continues to be applicable to the operations. The first step in the process must be to determine what is to be covered in the program assessment. While regulatory compliance audits are a component, the most useful evaluation will extend beyond looking only at compliance and determine whether the radiation safety program is the most appropriate for the particular operation. Several aspects of the irradiator operation, not all of which may routinely be considered "radiation safety", per se, should be included: Design aspects of the irradiator and operating system, system controls, and maintenance procedures, as well as the more traditional radiation safety program components such as surveys, measurements and training.

  20. Electron Irradiation of Interstellar Ice Analogues

    NASA Astrophysics Data System (ADS)

    Nair, B. G.; Mason, N. J.

    2011-05-01

    Molecular synthesis in the Universe primarily occurs in the icy mantles on dust grains in dense interstellar dust clouds. The interaction of photons, electrons and cosmic rays with these ice mantles triggers complex chemical synthesis leading to the formation of complex molecules. Such molecular reactions can only be understood by systematic laboratory studies. In our experiments astrophysical environments are recreated in the laboratory using an ultra high vacuum chamber (UHV) capable of reaching pressures of the order of 10 -10 mBar containing a liquid helium cryostat capable of attaining a temperature of 20 K. Ice films are deposited on a ZnSe substrate (cooled by cryostat) by background deposition and irradiated with electrons of 1KeV energy. Chemical changes induced by electron irradiation were monitored by an infrared spectrometer. By varying the temperature, we also investigate the temperature dependence on the kinetics of the reactions. In this poster we will present the first results of electron irradiation of simple organic molecules like formamide (HCONH2) and allyl alcohol (CH2CHCH2OH).

  1. Magnetic phase formation in irradiated austenitic alloys

    SciTech Connect

    Gussev, Maxim N [ORNL] [ORNL; Busby, Jeremy T [ORNL] [ORNL; Tan, Lizhen [ORNL] [ORNL; Garner, Francis A. [Radiation Effects Consulting, Richland, WA] [Radiation Effects Consulting, Richland, WA

    2014-01-01

    Austenitic alloys are often observed to develop magnetic properties during irradiation, possibly associated with radiation-induced acceleration of the ferrite phase. Some of the parametric sensitivities of this phenomenon have been addressed using a series of alloys irradiated in the BOR-60 reactor at 593K. The rate of development of magnetic phase appears to be sensitive to alloy composition. To the first order, the largest sensitivities to accelerate ferrite formation, as explored in this experiment, are associated with silicon, carbon and manganese and chromium. Si, C, and Mn are thought to influence diffusion rates of point defects while Cr plays a prominent role in defining the chromium equivalent and therefore the amount of ferrite at equilibrium. Pre-irradiation cold working was found to accelerate ferrite formation, but it can play many roles including an effect on diffusion, but on the basis of these results the dominant role or roles of cold-work cannot be identified. Based on the data available, ferrite formation is most probably associated with diffusion.

  2. Sequential half-body irradiation in childhood

    SciTech Connect

    Jenkin, R.D.T.; Berry, M.P.

    1983-12-01

    Single-dose half-body irradiation (HBI), introduced for the palliation of pain from widespread bone metastases in adults, has proved to be successful. The dose-limiting toxicity has proved to be acute radiation pneumonitis, with bone marrow tolerance of lesser importance, in spite of the fact that many patients received previous local irradiation and/or chemotherapy. Palliative HBI has not become a valuable treatment in pediatric malignancies, because of a shorter metastatic phase. Results are described in selected institutions, where HBI has been used in the treatment of pediatric malignancies. A single institution plot study was undertaken at the Princess Margaret Hospital involving 17 patients with Ewing's sarcoma of bone, without overt metastases at diagnosis. Results to date have not been obviously different from overall survival in the first intergroup Ewing's sarcoma study. Overall, the treatment has been shown to be well tolerated and can be given entirely on an out-patient basis. When compared on a historical basis with a previous single dose total body irradiation study, the one year survival rate was increased. HBI appears to be tolerable treatment, when given concurrently with or sequential to local and systemic treatment.

  3. Multivariate Analysis of Solar Spectral Irradiance Measurements

    NASA Technical Reports Server (NTRS)

    Pilewskie, P.; Rabbette, M.

    2001-01-01

    Principal component analysis is used to characterize approximately 7000 downwelling solar irradiance spectra retrieved at the Southern Great Plains site during an Atmospheric Radiation Measurement (ARM) shortwave intensive operating period. This analysis technique has proven to be very effective in reducing a large set of variables into a much smaller set of independent variables while retaining the information content. It is used to determine the minimum number of parameters necessary to characterize atmospheric spectral irradiance or the dimensionality of atmospheric variability. It was found that well over 99% of the spectral information was contained in the first six mutually orthogonal linear combinations of the observed variables (flux at various wavelengths). Rotation of the principal components was effective in separating various components by their independent physical influences. The majority of the variability in the downwelling solar irradiance (380-1000 nm) was explained by the following fundamental atmospheric parameters (in order of their importance): cloud scattering, water vapor absorption, molecular scattering, and ozone absorption. In contrast to what has been proposed as a resolution to a clear-sky absorption anomaly, no unexpected gaseous absorption signature was found in any of the significant components.

  4. Irradiation Environment of the Materials Test Station

    SciTech Connect

    Pitcher, Eric John [Los Alamos National Laboratory

    2012-06-21

    Conceptual design of the proposed Materials Test Station (MTS) at the Los Alamos Neutron Science Center (LANSCE) is now complete. The principal mission is the irradiation testing of advanced fuels and materials for fast-spectrum nuclear reactor applications. The neutron spectrum in the fuel irradiation region of MTS is sufficiently close to that of fast reactor that MTS can match the fast reactor fuel centerline temperature and temperature profile across a fuel pellet. This is an important characteristic since temperature and temperature gradients drive many phenomena related to fuel performance, such as phase stability, stoichiometry, and fission product transport. The MTS irradiation environment is also suitable in many respects for fusion materials testing. In particular, the rate of helium production relative to atomic displacements at the peak flux position in MTS matches well that of fusion reactor first wall. Nuclear transmutation of the elemental composition of the fusion alloy EUROFER97 in MTS is similar to that expected in the first wall of a fusion reactor.

  5. Recycling of irradiated high-density polyethylene

    NASA Astrophysics Data System (ADS)

    Navratil, J.; Manas, M.; Mizera, A.; Bednarik, M.; Stanek, M.; Danek, M.

    2015-01-01

    Radiation crosslinking of high-density polyethylene (HDPE) is a well-recognized modification of improving basic material characteristics. This research paper deals with the utilization of electron beam irradiated HDPE (HDPEx) after the end of its lifetime. Powder of recycled HDPEx (irradiation dose 165 kGy) was used as a filler into powder of virgin low-density polyethylene (LDPE) in concentrations ranging from 10% to 60%. The effect of the filler on processability and mechanical behavior of the resulting mixtures was investigated. The results indicate that the processability, as well as mechanical behavior, highly depends on the amount of the filler. Melt flow index dropped from 13.7 to 0.8 g/10 min comparing the lowest and the highest concentration; however, the higher shear rate the lower difference between each concentration. Toughness and hardness, on the other hand, grew with increasing addition of the recycled HDPEx. Elastic modulus increased from 254 to 450 MPa and material hardness increased from 53 to 59 ShD. These results indicate resolving the problem of further recycling of irradiated polymer materials while taking advantage of the improved mechanical properties.

  6. Repair of nonreplicating UV-irradiated DNA

    SciTech Connect

    Martin, S.J.; Hays, J.B.

    1986-05-01

    Repair of irradiated phage lambda DNA in E. coli has been studied by a repressed-infection system: superinfection of homoimmune lysogenic bacteria; assay for restoration of transcribility to phage-encoded lac genes; extraction of DNA and assay for infectivity in transfection of uvrB/sup -/ recA/sup -/ recB/sup -/ spheroplasts, and for removal of cyclobutane pyrimidine dimers (CBP-dimers) by UV-endonuclease treatment and alkaline sedimentation. In uvr/sup +/ repressed infections with 254-nm irradiated phages (60 J/m/sup 2/) lac transcription was rapidly returned to undamaged levels, concomitant with restoration of infectivity and removal of CBP-dimers. In uvrD/sup -/ cells, the frequency of phage gene inactivation corresponded to the estimated frequency of CBP-dimers per gene. In uvrA/sup -/ bacteria, however, lac expression was only 1/10 to 1/3 of that predicted by the expected frequency of gene inactivation, as if damage elsewhere affected transcription; recovery of infectivity and removal of CBP-dimers was almost completely inhibited. lac/sup +/ and lacUV5 phages, expected to respond oppositely to changes in superhelical density, were constructed as probes for topological changes during DNA repair. The assays for transfection infectivity and CBP-dimer-removal have been extended to studies of repair of UV-irradiated phage DNA injected into oocytes of the frog Xenopus laevis.

  7. METAPHIX-1 non destructive post irradiation examinations in the irradiated elements cell at Phenix

    SciTech Connect

    Breton, Laurent; Masson, M.; Garces, E.; Desjardins, S.; Fontaine, B. [Commissariat a l'Energie Atomique - CEA, Centrale Phenix, 30200 Bagnols Sur Ceze (France); Lacroix, B.; Martella, T.; Loubet, L. [Commissariat a l'Energie Atomique - CEA, Centre de Cadarache, 13108 Saint-Paul-Lez-Durance cedex (France); Ohta, H.; Yokoo, T. [Central Research Institute of Electric Power Industry - CRIEPI, 2-11-1 Iwado-kita, Komae, Tokyo 201-8511 (Japan); Ougier, M.; Glatz, J.P. [European Commission Joint Research, Institute for Transuranium Elements - JRC-ITU, Postfach 2340, D-76125 Karlsruhe (Germany)

    2007-07-01

    Central Research Institute of Electric Power Industry (CRIEPI) has been developing minor actinide (MA) transmutation technology in homogeneous loading mode by use of metal fuel fast reactors in cooperation with Institute for Transuranium Elements (ITU) and Commissariat a l'Energie Atomique (CEA). Fast reactor metal fuel pins of Uranium- Plutonium-Zirconium (U-Pu-Zr) alloy containing 2 wt% MAs and 2 wt% rare earth elements (REs), 5 wt% MAs, and 5 wt% MAs and 5 wt% REs were irradiated in the PHENIX French fast reactor as METAPHIX experiments. In these METAPHIX experiments, three rigs each consisting of three metal fuel experimental pins and sixteen oxide fuel driver pins were irradiated. The target burnup of the three rigs is 2.4 at%, 7 at% and 11 at% which corresponds to 120, 360 and 600 equivalent full power days (EFPD) in terms of irradiation periods, respectively. The low burnup rig of 2.4 at%, METAPHIX-1, was discharged from the core in August 2004. After cooling, the non-destructive post irradiation examinations (PIEs) of the rig (visual examination, measurement of rig length and deformation) and of the metal fuel pins (visual examination, measurement of pin length and deformation, {gamma}-spectrometry and neutron radiography) were conducted in the Irradiated Elements Cell (IEC) at PHENIX. (authors)

  8. Plant responses to UV-B irradiation are modified by UV-A irradiation

    SciTech Connect

    Middleton, E.M.; Teramura, A.H. (NASA/Goddard Space Flight Center, Greenbelt, MD (United States) Univ. of Maryland, College Park (United States))

    1993-06-01

    The increasing UV-B radiation (0.28-0.32 [mu]m) reaching the earth's surface is an important concern. Plant response in artificial UV-B irradiation studies has been difficult to assess, especially regarding photosynthetic pigments, because the fluorescent lamps also produce UV-A (0.32-0.40[mu]m) radiation which is involved with blue light in pigment synthesis. Both UV-A and UV-B irradiances were controlled in two glasshouse experiments conducted under relatively high PPFD (> 1300[mu]mol m[sup [minus]2] s[sup [minus]1]) at two biologically effective daily UV-B irradiances (10.7 and 14.1 kJ m[sup [minus]2]); UV-A irradiances were matched in Controls ([approximately]5, 9 kJ m[sup [minus]2]). Normal, chlorophyll-deficient, and flavonoid-deficient isolines of soybean cultivar, Clark, were utilized. Many growth/ pigment variables exhibited a statistically significant interaction between light quality and quantity: in general, UV-A radiation moderated the damaging effects of UV-B radiation. Regression analyses demonstrated that a single negative function related photosynthetic efficiency to carotenoid Content (r[sup 2] =0.73, P[le]0.001), implying a [open quotes]cost[close quotes] in maintaining carotenoids for photoprotection. A stomatal limitation to photosynthesis was verified and carotenoid content was correlated with UV-B absorbing compound levels, in UV-B irradiated plants.

  9. Analyzing UV-B narrowband solar irradiance: comparison with erythemal and vitamin D production irradiances.

    PubMed

    Sola, Yolanda; Lorente, Jerónimo; Ossó, Albert

    2012-12-01

    The heliotherapy and the phototherapy are mainly focused on taking benefit of the therapeutic effects of the ultraviolet (UV) irradiance on different skin diseases. The use of UV-B narrowband lamps, with emissions centered at 311 nm, has spread out among the dermatologist community because of its high therapeutic effect in comparison with its low erythema dose. For cloudless sun exposure, the balance of solar erythemal and solar narrowband (NB)-equivalent irradiances depends on several factors such as the solar zenith angle (SZA), the total ozone column (TOC) and the altitude. For SZA below 55°, the ratio of solar UV-B narrowband and erythemal irradiances increases with the SZA whereas the ratio of vitamin D production and erythemal irradiances decreases with the SZA with the maximum around midday. Furthermore, the solar NB ratio also increases with the TOC because the shorter wavelengths of the erythemal action spectrum are more affected by the ozone absorption processes. Considering the daily variations of the ratio between narrowband and erythemal irradiance, sun exposures avoiding midday hours are recommended in order to prevent negative side-effects. However to accumulate great NB doses and sufficient vitamin D in winter months is difficult because the time exposures may be longer than the day duration. PMID:23092623

  10. Comparison of structural properties of pristine and gamma irradiated single-wall carbon nanotubes: Effects of medium and irradiation dose

    SciTech Connect

    Kleut, D. [Vinca Institute of Nuclear Sciences, P.O.B. 522, University of Belgrade, 11001 Belgrade (Serbia)] [Vinca Institute of Nuclear Sciences, P.O.B. 522, University of Belgrade, 11001 Belgrade (Serbia); Jovanovic, S., E-mail: svetlanajovanovic@vinca.rs [Vinca Institute of Nuclear Sciences, P.O.B. 522, University of Belgrade, 11001 Belgrade (Serbia); Markovic, Z.; Kepic, D.; Tosic, D. [Vinca Institute of Nuclear Sciences, P.O.B. 522, University of Belgrade, 11001 Belgrade (Serbia)] [Vinca Institute of Nuclear Sciences, P.O.B. 522, University of Belgrade, 11001 Belgrade (Serbia); Romcevic, N. [Insitute of Physics, P.O.B. 68, University of Belgrade, 11001 Belgrade (Serbia)] [Insitute of Physics, P.O.B. 68, University of Belgrade, 11001 Belgrade (Serbia); Marinovic-Cincovic, M.; Dramicanin, M. [Vinca Institute of Nuclear Sciences, P.O.B. 522, University of Belgrade, 11001 Belgrade (Serbia)] [Vinca Institute of Nuclear Sciences, P.O.B. 522, University of Belgrade, 11001 Belgrade (Serbia); Holclajtner-Antunovic, I. [Faculty of Physical Chemistry, P.O.B. 47, University of Belgrade, 11158 Belgrade (Serbia)] [Faculty of Physical Chemistry, P.O.B. 47, University of Belgrade, 11158 Belgrade (Serbia); Pavlovic, V. [Faculty of Agriculture, P.O.B. 127, University of Belgrade, 11080 Belgrade (Serbia)] [Faculty of Agriculture, P.O.B. 127, University of Belgrade, 11080 Belgrade (Serbia); Drazic, G. [Jozef Stefan Institute, Jamova 39, 1000 Ljubljana (Slovenia)] [Jozef Stefan Institute, Jamova 39, 1000 Ljubljana (Slovenia); Milosavljevic, M.; Todorovic Markovic, B. [Vinca Institute of Nuclear Sciences, P.O.B. 522, University of Belgrade, 11001 Belgrade (Serbia)] [Vinca Institute of Nuclear Sciences, P.O.B. 522, University of Belgrade, 11001 Belgrade (Serbia)

    2012-10-15

    A systematic study of the gamma irradiation effects on single wall carbon nanotube (SWCNT) structure was conducted. Nanotubes were exposed to different doses of gamma irradiation in three media. Irradiation was carried out in air, water and aqueous ammonia. Thermogravimetric analysis (TGA), Fourier transform infrared spectroscopy (FTIR), elemental analysis (EA) and Raman spectroscopy confirmed the changes in the SWCNT structure. TGA measurements showed the highest percentage of introduced groups for the SWCNTs irradiated with 100 kGy. FTIR spectroscopy provided evidence for the attachment of hydroxyl, carboxyl and nitrile functional groups to the SWCNT sidewalls. Those groups were confirmed by EA. All irradiated SWCNTs had hydroxyl and carboxyl groups irrelevant to media used for irradiation, but nitrile functional groups were only identified in SWCNTs irradiated in aqueous ammonia. Raman spectroscopy indicated that the degree of disorder in the carbon nanotube structure correlates with the irradiation dose. For the nanotubes irradiated with the dose of 100 kGy, the Raman I{sub D}/I{sub G} ratio was three times higher than for the pristine ones. Atomic force microscopy showed a 50% decrease in nanotube length at a radiation dose of 100 kGy. Scanning and transmission electron microscopies showed significant changes in the morphology and structure of gamma irradiated SWCNTs. - Highlights: Black-Right-Pointing-Pointer Gamma irradiation causes SWCNT covalent functionalization. Black-Right-Pointing-Pointer Type of covalently attached groups to SWCNT surface depends on irradiation medium. Black-Right-Pointing-Pointer The SWCNT shortening level increases with applied irradiation dose. Black-Right-Pointing-Pointer The average length of carbon nanotubes decreased by 50% at the highest dose. Black-Right-Pointing-Pointer The diameter of SWCNT bundles becomes small as irradiation dose rises.

  11. The spectral irradiance traceability chain at PTB

    NASA Astrophysics Data System (ADS)

    Sperfeld, P.; Pape, S.; Nevas, S.

    2013-05-01

    Spectral irradiance is a fundamental radiometric unit. Its application to measurement results requires qualified traceability to basic units of the international system of units (Système international d'unités, SI). The Physikalisch-Technische Bundesanstalt (PTB) is amongst other national metrological institutes (NMIs) responsible for the realization, maintenance and dissemination of various radiometric and photometric units based on and traceable to national standards. The unit of spectral irradiance is realized and represented by a blackbody-radiator as the national primary standard of the PTB. Based on Planck's radiation law, the irradiance is calculated and realized for any wavelength taking into account the exact knowledge of the radiation temperature and the geometrical parameters. Using a double-monochromator-based spectroradiometer system, secondary standard lamps can be calibrated by direct comparison to the blackbody-radiator (substitution method). These secondary standard lamps are then used at the PTB to calibrate standard lamps of customers. The customers themselves use these so-called transfer standards to calibrate their working standard lamps. These working standards are then used to calibrate own spectroradiometers or sources. This rather complex calibration chain is a common procedural method that for the customers generally leads to satisfying measurement results on site. Nevertheless, the standard lamps in use have to fulfill highest requirements concerning stability and reproducibility. Only this allows achieving comparably low transfer measurement uncertainties, which occur at each calibration step. Thus, the PTB is constantly investigating the improvement and further development of transfer standards and measurement methods for various spectral regions. The realization and dissemination of the spectral irradiance using the blackbody-radiator at the PTB is accomplished with worldwide approved minimized measurement uncertainties confirmed by international intercomparisons among NMIs. Ultimately, the spectral irradiance can be realized with expanded measurement uncertainties of far less than 1 % over a wide spectral range. Thus, for customers with high demands on low measurement uncertainties, it is possible to calibrate their working standards directly against the blackbody-radiator, taking into account the higher necessary effort. In special cases it is possible to calibrate the customer's spectroradiometric facilities directly in front of the blackbody-radiator. In the context of the European Metrology Research Project Traceability for surface spectral solar ultraviolet radiation, the traceability chain will be improved and adapted.

  12. EFFECTS OF GAMMA IRRADIATION ON EPDM ELASTOMERS

    SciTech Connect

    Clark, E.

    2011-09-22

    Two formulations of EPDM elastomer, one substituting a UV stabilizer for the normal antioxidant in this polymer, and the other the normal formulation, were synthesized and samples of each were exposed to gamma irradiation in initially pure deuterium gas to compare their radiation stability. Stainless steel containers having rupture disks were designed for this task. After 130 MRad dose of cobalt-60 radiation in the SRNL Gamma Irradiation Facility, a significant amount of gas was created by radiolysis; however the composition indicated by mass spectroscopy indicated an unexpected increase in the total amount deuterium in both formulations. The irradiated samples retained their ductility in a bend test. No change of sample weight, dimensions, or density was observed. No change of the glass transition temperature as measured by dynamic mechanical analysis was observed, and most of the other dynamic mechanical properties remained unchanged. There appeared to be an increase in the storage modulus of the irradiated samples containing the UV stabilizer above the glass transition, which may indicate hardening of the material by radiation damage. Polymeric materials become damaged by exposure over time to ionizing radiation. Despite the limited lifetime, polymers have unique engineering material properties and polymers continue to be used in tritium handling systems. In tritium handling systems, polymers are employed mainly in joining applications such as valve sealing surfaces (eg. Stem tips, valve packing, and O-rings). Because of the continued need to employ polymers in tritium systems, over the past several years, programs at the Savannah River National Laboratory have been studying the effect of tritium on various polymers of interest. In these studies, samples of materials of interest to the SRS Tritium Facilities (ultra-high molecular weight polyethylene (UHMW-PE), polytetrafluoroethylene (PTFE, Teflon{reg_sign}), Vespel{reg_sign} polyimide, and the elastomer ethylene propylene diene monomer (EPDM)) have been exposed in closed containers to tritium gas initially at 1 atmosphere pressure. These studies have demonstrated the degradation of properties when exposed to tritium gas. Also, the radiolytic production of significant amounts of hydrogen has been observed for UHMW-PE and EPDM. The study documented in this report exposes two similar formulations of EPDM elastomer to gamma irradiation in a closed container backfilled with deuterium. Deuterium is chemically identical to protium and tritium, but allows the identification of protium that is radiolytically produced from the samples. The goal of this program is to compare and contrast the response of EPDM exposure to two different types of ionizing radiation in a similar chemical environment.

  13. Germination test for identification of gamma-irradiated wheat

    NASA Astrophysics Data System (ADS)

    Kawamura, Yoko; Suzuki, Naomi; Uchiyama, Sadao; Saito, Yukio

    The germination of wheat provides a reliable test for the identification of wheat that has been subjected to irradiation. Germination success of non-irradiated wheat is not affected by storage time and temperature. Root and shoot lengths are more sensitive to ?-irradiation than the germination percentages. The critical dose that inhibits root elongation varies from 0.15 to 0.5 kGy for imported cultivars and from 0.3 to 1.0 kGy for domestic cultivars. Germination percentage is reduced above 5.0 kGy. The difference in radiosensitivity between imported and domestic cultivars may be the result of differences in moisture content. In addition, storage periods of up to 12 months have little effect on irradiation-induced reduction of root length. Fumigation with methyl bromide inhibits root growth, but this inhibition can be distinguished from ?-irradiation effects by the germination pattern. Most imported wheat samples that were irradiated above 0.5 kGy exhibit root growths of less than 20 mm after 4 days of culturing under the specified conditions. The same behavior was noted in domestic wheat samples that were irradiated at or above 1.0 kGy. This test can thus discriminate between irradiated and non-irradiated wheat even 12 months after ?-irradiation.

  14. Evaluation of Neutron Irradiated Silicon Carbide and Silicon Carbide Composites

    SciTech Connect

    Newsome G, Snead L, Hinoki T, Katoh Y, Peters D

    2007-03-26

    The effects of fast neutron irradiation on SiC and SiC composites have been studied. The materials used were chemical vapor deposition (CVD) SiC and SiC/SiC composites reinforced with either Hi-Nicalon{trademark} Type-S, Hi-Nicalon{trademark} or Sylramic{trademark} fibers fabricated by chemical vapor infiltration. Statistically significant numbers of flexural samples were irradiated up to 4.6 x 10{sup 25} n/m{sup 2} (E>0.1 MeV) at 300, 500 and 800 C in the High Flux Isotope Reactor at Oak Ridge National Laboratory. Dimensions and weights of the flexural bars were measured before and after the neutron irradiation. Mechanical properties were evaluated by four point flexural testing. Volume increase was seen for all bend bars following neutron irradiation. Magnitude of swelling depended on irradiation temperature and material, while it was nearly independent of irradiation fluence over the fluence range studied. Flexural strength of CVD SiC increased following irradiation depending on irradiation temperature. Over the temperature range studied, no significant degradation in mechanical properties was seen for composites fabricated with Hi-Nicalon{trademark} Type-S, while composites reinforced with Hi-Nicalon{trademark} or Sylramic fibers showed significant degradation. The effects of irradiation on the Weibull failure statistics are also presented suggesting a reduction in the Weibull modulus upon irradiation. The cause of this potential reduction is not known.

  15. Microstructural changes induced by post-irradiation annealing of neutron-irradiated austenitic stainless steels

    NASA Astrophysics Data System (ADS)

    Cole, J. I.; Allen, T. R.

    2000-12-01

    Irradiated EBR-II hexagonal 'hex' duct material fabricated from 304 stainless steel (SS) is characterized prior to and following in situ annealing in the transmission electron microscope (TEM) at temperatures between 400°C and 600°C for various lengths of time. The hex duct samples were irradiated at temperatures between 375°C and 389°C to doses up to 29 dpa over a range of dose rates. The pre-annealed microstructure of the irradiated hex ducts exhibited substantial radiation-induced dislocation development (networks and loops) and cavity formation (bubbles and voids). Following annealing at all temperatures, dislocation loop densities decrease significantly and the dislocation network density increases. Annealing at 500°C and 600°C led to the shrinking or disappearance of many larger faceted voids. In addition to shrinkage of larger voids, small spherical bubbles formed leading to an increase in the overall cavity density and a decrease in the average cavity size.

  16. The irradiation facility KORPUS for irradiation of the reactor structure materials

    SciTech Connect

    Brodkin, E.B.; Egorov, A.L.; Zaritsky, S.M. [Kurchatov Inst., Moscow (Russian Federation). Russian Research Centre; Golovanov, V.N.; Markina, N.V.; Raetsky, V.M.; Sulaberidze, V.S.; Tsikanov, V.A. [Research Inst. of Atomic Reactors, Dimitrovgrad (Russian Federation)

    1994-12-31

    The results concerning the irradiation embrittlement of WWER vessel materials prove the necessity of organizing experiments in controllable and adjustable conditions ensuring the unequivocal interpretation of the change of material properties under irradiation. The KORPUS facility for RBT-6 reactor was designed and made for the realization of controllable irradiation with the possibility of a simulation of reactor WWER vessel materials working conditions. The KORPUS design and technical characteristics are considered in this paper. Its experimental possibilities from the point of view of material testing and reactor dosimetry execution are discussed. The precomputation results indicative of possible simulation of vessel material working conditions are presented. The proposals on creating dosimetry experimental conditions are formulated.

  17. Development of microstructure and irradiation hardening of Zircaloy during low dose neutron irradiation at nominally 377-440 °C

    NASA Astrophysics Data System (ADS)

    Cockeram, B. V.; Leonard, K. J.; Byun, T. S.; Snead, L. L.; Hollenbeck, J. L.

    2014-06-01

    Neutron irradiation of wrought Zircaloy-2 and Zircaloy-4 was performed in the Advanced Test Reactor (ATR) at irradiation temperatures of nominally 377-440 °C to relatively low neutron fluences between 3 and 31 × 1024 n/m2 (E >1 MeV). The irradiation hardening was measured using tensile testing. For this relatively high application temperature (377-440 °C) saturation of hardening was observed at the relatively low dose of 3 and 8 × 1024 n/m2, but the magnitude of irradiation hardening is much less than reported in the literature for lower irradiation temperatures of 260-326 °C. Examinations of microstructure were used to show that a lower number density of loops is present that results in the lower level of irradiation hardening. The lower irradiation hardening for the higher irradiation temperature is consistent with literature data. The amorphization of Zr(Fe,Cr)2 precipitates and resulting change in precipitate composition during irradiation is characterized, and the potential role of these effects on loop and loop formation and irradiation hardening is discussed.

  18. Ion irradiated graphite exposed to fusion-relevant deuterium plasma

    NASA Astrophysics Data System (ADS)

    Deslandes, Alec; Guenette, Mathew C.; Corr, Cormac S.; Karatchevtseva, Inna; Thomsen, Lars; Ionescu, Mihail; Lumpkin, Gregory R.; Riley, Daniel P.

    2014-12-01

    Graphite samples were irradiated with 5 MeV carbon ions to simulate the damage caused by collision cascades from neutron irradiation in a fusion environment. The ion irradiated graphite samples were then exposed to a deuterium plasma in the linear plasma device, MAGPIE, for a total ion fluence of ?1 × 1024 ions m-2. Raman and near edge X-ray absorption fine structure (NEXAFS) spectroscopy were used to characterize modifications to the graphitic structure. Ion irradiation was observed to decrease the graphitic content and induce disorder in the graphite. Subsequent plasma exposure decreased the graphitic content further. Structural and surface chemistry changes were observed to be greatest for the sample irradiated with the greatest fluence of MeV ions. D retention was measured using elastic recoil detection analysis and showed that ion irradiation increased the amount of retained deuterium in graphite by a factor of four.

  19. Safety evaluation of irradiated foods in China: A condensed report

    SciTech Connect

    Yin, D. (Institute of Food Safety Control and Inspection, Beijing (China))

    1989-03-01

    Eight trials, with 439 human volunteers who consumed irradiated foods including rice, potatoes, mushrooms, peanuts, and Chinese sausages, as well as diets composed of multiple irradiated foods (irradiated at dosages of 0.2 to 8 kGy) that accounted for 60-66% of the entire diet, were carried out for 2-3 months according to a unified protocol. No adverse effects on body weight, blood pressure, ECG, hematology, blood enzyme activities, serum lipids or blood or urine 17-hydroxycortisol contents and no chromosomal aberration of peripheral blood lymphocytes were found. It is especially worthwhile to note that there was no change in the polyploidy after consumption of irradiated diets. On the basis of these results and a comprehensive analysis of the physical and chemical characteristics of irradiated foods, temporary hygienic standards for irradiated rice, potatoes, onions, garlic, Chinese sausages, peanuts, and mushrooms were promulgated by the Chinese Ministry of Public Health.

  20. Modelling rotational and cyclical spectral solar irradiance variations

    NASA Astrophysics Data System (ADS)

    Unruh, Yvonne

    Solar irradiance changes are highly wavelength dependent: solar-cycle variations in the UV can be on the order of tens of percent, while changes in the visible are typically only of the order of one or two permille. With the launch of a number of instruments to measure spectral solar irradiance, we are now for a first time in a good position to explore the changing solar irradiance over a large range of wavelengths and to test our irradiance models as well as some of their underlying assumptions. I will introduce some of the current modelling approaches and present model-data comparisons, using the SATIRE irradiance model and SORCE/SIM measurements as an example. I will conclude by highlighting a number of outstanding questions regarding the modelling of spectral irradiance and current approaches to address these.

  1. The live cell irradiation and observation setup at SNAKE

    NASA Astrophysics Data System (ADS)

    Hable, V.; Greubel, C.; Bergmaier, A.; Reichart, P.; Hauptner, A.; Krücken, R.; Strickfaden, H.; Dietzel, S.; Cremer, T.; Drexler, G. A.; Friedl, A. A.; Dollinger, G.

    2009-06-01

    We describe a new setup at the ion microprobe SNAKE ( Superconducting Nanoscope for Applied nuclear ( Kern-) physics Experiments) at the Munich 14 MV Tandem accelerator that facilitates both living cell irradiation with sub micrometer resolution and online optical imaging of the cells before and after irradiation by state of the art phase contrast and fluorescence microscopy. The cells are kept at standard cell growth conditions at 37 °C in cell culture medium. After irradiation it is possible to switch from single ion irradiation conditions to cell observation within 0.5 s. First experiments were performed targeting substructures of a cell nucleus that were tagged by TexasRed labeled nucleotides incorporated in the cellular DNA by 55 MeV single carbon ion irradiation. In addition we show first online sequences of short time kinetics of Mdc1 protein accumulation in the vicinity of double strand breaks after carbon ion irradiation.

  2. Commercialization of food irradiation in the U.S.A.

    NASA Astrophysics Data System (ADS)

    Cottee, Jim; Kunstadt, Peter; Fraser, Frank

    1995-02-01

    Commercializing food irradiation in the United States has been a major marketing and business challenge. This paper begins by examining the situation before America's first food irradiator was established, in 1992. With the Vindicator irradiator in place, beneficial changes and market offerings took place, amidst perceived activist threats and disinterest from the food industry. Initial efforts to market irradiated foods were made by independents in the food business, as part of their attempts to differentiate themselves from large food companies and grocery chains. Special tactics were needed to launch products into sensitive and fearful market-places. The brisk sales of irradiated foods in small, initial markets, has been an unexpected success. This paper discusses the methods used to promote positive awareness of irradiated foods nationally, building on small local successes.

  3. Esophageal fistula associated with intracavitary irradiation for esophageal carcinoma

    SciTech Connect

    Hishikawa, Y.; Tanaka, S.; Miura, T.

    1986-05-01

    Fifty-three patients with esophageal carcinoma were treated with high-dose-rate intracavitary irradiation following external irradiation. Ten patients developed esophageal fistula. Perforations were found in the bronchus (four), major vessels (four), pericardium (one), and mediastinum (one). The frequency of fistula occurrence in these patients was not remarkably different from that in 30 other patients treated only with greater than or equal to 50 Gy external irradiation. From the time of the development of esophageal fistula, intracavitary irradiation did not seem to accelerate the development of fistula. The fistulas in our ten patients proved to be associated with tumor, deep ulcer (created before intracavitary irradiation), chemotherapy, infection, and trauma rather than the direct effect of intracavitary irradiation.

  4. Up-to-date status of food irradiation

    NASA Astrophysics Data System (ADS)

    Ahmed, Mainuddin

    1993-07-01

    The last decade has witnessed significant advancement of the acceptance of food irradiation processing. At present 37 countries have approved one or more food items for human consumption and 25 countries have commercialized this process. More developing countries are showing keen interest to introduce irradiation processing in order to reduce post-harvest food losses, to increase export potentials and to ensure safety of food to their people. Although progress towards acceptance of food irradiation by the industry is slow, actual market trials have shown that once consumers have understood this technology, they are willing to buy irradiated foods. This paper deals with the latest developments in the field of food irradiation with particular reference to legislation, consumer acceptance, commercialization and potential application in developing countries. This paper also deals with the role played by the International Organizations, aimed at facilitating the acceptance of food irradiation.

  5. Thermal analysis of the FSP-1RR irradiation test

    SciTech Connect

    Webb, R.H.; Lyon, W.F. III

    1992-10-14

    The thermal analysis of four unirradiated fuel pins to be tested in the FSP-1RR fuels irradiation experiment was completed. This test is a follow-on experiment in the series of fuel pin irradiation tests conducted by the SP-100 Program in the Fast Flux Test Facility. One of the pins contains several meltwire temperature monitors within the fuel and the Li annulus. A post-irradiation examination will verify the accuracy of the pre-irradiation thermal analysis. The purpose of the pre-irradiation analysis was to determine the appropriate insulating gap gas compositions required to provide the design goal cladding operating temperatures and to ensure that the meltwire temperature ranges in the temperature monitored pin bracket peak irradiation temperatures. This paper discusses the methodology and summarizes the results of the analysis.

  6. Model for UV irradiance on arbitrarily oriented surfaces

    NASA Astrophysics Data System (ADS)

    Mech, M.; Koepke, P.

    Erythemal weighted solar UV irradiances, responsible for damage to human skin, need to be known for arbitrarily oriented surfaces, since human skin has various orientations to the sun. A model for determining such irradiances is presented with the results in good agreement with measurements. The model gives spectral or biologically weighted irradiances for any user-defined orientation of a flat receiver and for selectable atmospheric and surface conditions.

  7. The effects of gamma irradiation on Serratia marcescens

    E-print Network

    Bartlett, William Thomas

    1969-01-01

    ABSTRACT The Effects of Gamma Irradiation on Serratia Marcescens (August 1969) William T. Bartlett, B. A. , Austin College M. S. , Texas AFM University Directed by: Dr. R. D. Neff The effects of Co gamma radiation on the production of the red pigment... to to gamma radiation. 10 Pigment production of Serratia marcescens post-irradiation and 66 hours incubation. . . 13 OBJECTIVE The effects of gamma irradiation on Serratia marcescens were studied by the use of the following methods: a) measurement of a...

  8. Behavior of Thin Film Materials Under ? Irradiation for Astronomical Optics

    NASA Astrophysics Data System (ADS)

    di Sarcina, Ilaria; Piegari, Angela; Cecilia, Angelica

    2006-04-01

    A set of optical coating materials for astronomical and space applications were submitted to ? irradiation at the 60Co radioisotope source (ENEA-Casaccia Research Center) in order to simulate the hostile radiation environment in which optical instrumentation is working. Firstly, samples were submitted to 50 Gy irradiation dose, typical of Low Earth Orbit missions. Successively, coatings were irradiated at doses between 1000-8400 Gy characterizing interplanetary mission expositions.

  9. Effect of gamma irradiation on trichromatic values of spices

    Microsoft Academic Search

    J. Horváthová; M. Suhaj; M. Polovka

    2007-01-01

    The effect of ?-irradiation on trichromatic color values L*, a*, and b* was determined in black pepper, oregano, and allspice samples irradiated at average doses from 5 kGy to 30 kGy. Trichromatic\\u000a values a* measured in methanol extracts of treated spices immediately after the irradiation process were significantly changed, but\\u000a the subsequent storage of allspice and oregano caused much more

  10. Amino Acids from Ion-Irradiated Nitrile-Containing Ices

    Microsoft Academic Search

    Reggie L. Hudson; Marla H. Moore; Jason P. Dworkin; Mildred P. Martin; Zachary D. Pozun

    2008-01-01

    Solid CH3CN and solid H2OCH3CN were ion irradiated near 10 K to initiate chemical reactions thought to occur in extraterrestrial ices. The infrared spectra of these samples after irradiation revealed the synthesis of new molecules. After the irradiated ices were warmed to remove volatiles, the resulting residual material was extracted and analyzed. Both unhydrolyzed and acid-hydrolyzed residues were examined by

  11. EFFECTS OF ELECTRON BEAM IRRADIATION ON BOVINE PERICARDIUM TISSUE

    Microsoft Academic Search

    Roberta Polak; Andrea C. D. Rodas; Yasko Kodama; Olga Z. Higa; Luci D. B. Machado; Ronaldo N. M. Pitombo

    In this work, electron beam irradiation was studied as a way for bovine pericardium (BP) tissue crosslinking. BP samples were irradiated in an electron beam accelerator at different doses (12.5 and 25 kGy), at three different dose ratios (4.67, 9.34 kGy\\/s), in the presence and absence of oxygen. Irradiated samples were analyzed by Differential Scanning Calorimetry (DSC), Thermogravimetry (TGA), Scanning

  12. Solar Irradiance Variations on Active Region Time Scales

    NASA Technical Reports Server (NTRS)

    Labonte, B. J. (editor); Chapman, G. A. (editor); Hudson, H. S. (editor); Willson, R. C. (editor)

    1984-01-01

    The variations of the total solar irradiance is an important tool for studying the Sun, thanks to the development of very precise sensors such as the ACRIM instrument on board the Solar Maximum Mission. The largest variations of the total irradiance occur on time scales of a few days are caused by solar active regions, especially sunspots. Efforts were made to describe the active region effects on total and spectral irradiance.

  13. On the ?T 41 criterion for irradiation shift

    Microsoft Academic Search

    I. J. O'Donnell; R. Crombie

    1996-01-01

    Current methodologies for assessing the effects of neutron irradiation on the ductile to brittle transition in reactor pressure vessel steels include the use of the Charpy-based ?T41 irradiation shift criterion. This criterion is commonly used in the assessment of irradiation shift for setting limits to the pressure\\/temperature operating diagram and in defect assessment methodologies. In both of these cases the

  14. Radiolysis of biogenic amines in model system by gamma irradiation

    Microsoft Academic Search

    Jae Hyun Kim; Hyun Joo Ahn; Cheorun Jo; Hyun Jin Park; Young Jin Chung; Myung Woo Byun

    2004-01-01

    Irradiation effects on nine kinds of biogenic amine (BA) standards, putrescine, cadaverine, ?-phenylethylamine, spermidine, spermine, tryptamine, histamine, tyramine, and agmatine were investigated. The standards were dissolved in distilled water with a concentration of 10 mg%, and gamma-irradiated at 2.5, 5, 10, 20, or 25 kGy. Gamma-irradiation destroyed 5–100% of the BAs. Significant degradation of putrescine, spermidine, and spermine occurred in

  15. Post-irradiation stability of polyvinyl chloride at sterilizing doses

    Microsoft Academic Search

    F. Naimian; A. A. Katbab; H. Nazokdast

    1994-01-01

    Post-irradiation stability of plasticized PVC irradiated by 60Co gamma ray at sterilizing doses has been studied. Effects of irradiation upon chemical structure, mechanical properties and rheological behaviour of samples contained different amounts of Di(2-ethylhexyl)phthalate as plasticizer have been investigated. Formation of conjugated double bonds, carbonyl and hydroxyl groups have been followed by UV and FTIR spectrometers up to 6 months

  16. Checking ozone amounts by measurements of UV-irradiances

    NASA Technical Reports Server (NTRS)

    Seckmeyer, Gunther; Kettner, Christiane; Thiel, Stephen

    1994-01-01

    Absolute measurements of UV-irradiances in Germany and New Zealand are used to determine the total amounts of ozone. UV-irradiances measured and calculated for clear skies and for solar zenith angles less than 60 deg generally show a good accordance. The UVB-irradiances, however, show that the actual Dobson values are about 5 percent higher in Germany and about 3 percent higher in New Zealand compared to those obtained by our method. Possible reasons for these deviations are discussed.

  17. NANOSTRUCTURE PATTERNING UNDER ENERGETIC PARTICLE BEAM IRRADIATION

    SciTech Connect

    Wang, Lumin [Regents of the University of Michigan; Lu, Wei [Regents of the University of Michigan

    2013-01-31

    Energetic ion bombardment can lead to the development of complex and diverse nanostructures on or beneath the material surface through induced self-organization processes. These self-organized structures have received particular interest recently as promising candidates as simple, inexpensive, and large area patterns, whose optical, electronic and magnetic properties are different from those in the bulk materials [1-5]. Compared to the low mass efficiency production rate of lithographic methods, these self-organized approaches display new routes for the fabrication of nanostructures over large areas in a short processing time at the nanoscale, beyond the limits of lithography [1,4]. Although it is believed that surface nanostructure formation is based on the morphological instability of the sputtered surface, driven by a kinetic balance between roughening and smoothing actions [6,7], the fundamental mechanisms and experimental conditions for the formation of these nanostructures has still not been well established, the formation of the 3-D naopatterns beneath the irradiated surface especially needs more exploration. During the last funding period, we have focused our efforts on irradiation-induced nanostructures in a broad range of materials. These structures have been studied primarily through in situ electron microscopy during electron or ion irradiation. In particular, we have performed studies on 3-D void/bubble lattices (in metals and CaF2), embedded sponge-like porous structure with uniform nanofibers in irradiated semiconductors (Ge, GaSb, and InSb), 2-D highly ordered pattern of nanodroplets (on the surface of GaAs), hexagonally ordered nanoholes (on the surface of Ge), and 1-D highly ordered ripple and periodic arrays (of Cu nanoparticles) [3,8-11]. The amazing common feature in those nanopatterns is the uniformity of the size of nanoelements (nanoripples, nanodots, nanovoids or nanofibers) and the distance separating them. Our research focuses on the understanding of fundamental scientific basis for the irradiation-induced self-organization processes. The fundamental physical mechanisms underlying ordered pattern formation, which include defect production and migration, ion sputtering, redeposition, viscous flow and diffusion, are investigated through a combination of modeling and in situ and ex-situ observations [3,9,11]. In addition, these nanostructured materials exhibit considerable improvement of optical properties [9,12,13]. For example, patterned Ge with a hexagonally ordered, honeycomb-like structure of nanoscale holes possesses a high surface area and a considerably blue-shifted energy gap [9], and oxidation of ordered Ga droplets shows noticeable enhancement of optical transmission [12]. This research has addressed nanopattern formation in a variety of materials under ion bombardment and provided a fundamental understanding of the dynamic mechanisms involved. In addition, have also stared to systematically investigate pattern formation under ion irradiation for more systems with varied experimental conditions and computation, including the collaboration with Dr. Veena Tikare of Sandia National Laboratory with a hybrid computation method at the ending this grant. A more detailed relationship between nanostructure formation and experimental conditions will be revealed with our continued efforts.

  18. A Simplified Shuttle Irradiation Facility for ATR

    SciTech Connect

    Palmer, Alma Joseph; Laflin, S. T.

    1999-09-01

    During the past fifteen years there has been a steady increase in the demand for radioisotopes in nuclear medicine and a corresponding decline in the number of reactors within the U.S. capable of producing them. The Advanced Test Reactor (ATR) is the largest operating test reactor in the U.S., but its isotope production capabilities have been limited by the lack of an installed isotope shuttle irradiation system. A concept for a simple “low cost” shuttle irradiation facility for ATR has been developed. Costs were reduced (in comparison to previous ATR designs) by using a shielded trough of water installed in an occupiable cubicle as a shielding and contamination control barrier for the send and receive station. This shielding concept also allows all control valves to be operated by hand and thus the need for an automatic control system was eliminated. It was determined that 4 – 5 ft of water would be adequate to shield the isotopes of interest while shuttles are transferred to a small carrier. An additional feature of the current design is a non-isolatable by-pass line, which provides a minimum coolant flow to the test region regardless of which control valves are opened or closed. This by-pass line allows the shuttle facility to be operated without bringing reactor coolant water into the cubicle except for send and receive operations. The irradiation position selected for this concept is a 1.5 inch “B” hole (B-11). This position provides neutron fluxes of approximately: 1.6 x 1014 (<0.5 eV) and 4.0 x 1013 (>0.8 MeV) n/cm2*sec.

  19. Solar Irradiance and Thermospheric Airglow Rocket Experiments

    NASA Technical Reports Server (NTRS)

    Solomon, Stanley C.

    1998-01-01

    This report describes work done in support of the Solar Irradiance and Thermospheric Air-glow Rocket Experiments at the University of Colorado for NASA grant NAG5-5021 under the direction of Dr. Stanley C. Solomon. (The overall rocket program is directed by Dr. Thomas N. Woods, formerly at the National Center for Atmospheric Research, and now also at the University of Colorado, for NASA grant NAG5-5141.) Grant NAG5-5021 provided assistance to the overall program through analysis of airglow and solar data, support of two graduate students, laboratory technical services, and field support. The general goals of the rocket program were to measure the solar extreme ultraviolet spectral irradiance, measure the terrestrial far-ultraviolet airglow, and analyze their relationship at various levels of solar activity, including near solar minimum. These have been met, as shown below. In addition, we have used the attenuation of solar radiation as the rocket descends through the thermosphere to measure density changes. This work demonstrates the maturity of the observational and modeling methods connecting energetic solar photon fluxes and airglow emissions through the processes of photoionization and photoelectron production and loss. Without a simultaneous photoelectron measurement, some aspects of this relationship remain obscure, and there are still questions pertaining to cascade contributions to molecular and atomic airglow emissions. However, by removing the solar irradiance as an "adjustable parameter" in the analysis, significant progress has been made toward understanding the relationship of far-ultraviolet airglow emissions to the solar and atmospheric conditions that control them.

  20. ESR investigation of gamma irradiated sulbactam sodium.

    PubMed

    Yurus, Sevgi; Ozbey, Turan; Korkmaz, Mustafa

    2004-09-01

    In the present work, radiolysis of gamma irradiated sulbactam sodium (SS) was investigated through detailed ESR studies performed at low and at high temperatures on the radiolytic products induced in this drug after gamma irradiation in the dose range of 3-15 kGy. While unirradiated SS presented no ESR signal, irradiated SS exhibited an ESR spectrum with many resonance peaks. Variations of the spectrum pattern and of the intensities of resonance peaks with microwave power, applied radiation dose, storage time and temperature were followed. A radical with unpaired electron localised on the carbon atom of five membered ring directly attached to two CH(3) groups and SO(2)(-) ionic radical called as species A and B, respectively, were found to be produced after gamma radiolysis of SS. The characteristic spectral and kinetic features of these species were determined by spectrum simulation calculation and by curve fitting techniques using experimental signal intensity data as input. Although, species A was fairly unstable at room and especially at high temperatures, species B were observed to be relatively stable even at high temperatures having activation energies of E(A) (+/-4)kJ/mol and E(B) (+/-3)kJ/mol, respectively, at room temperature. Four different mathematical functions were tried to explore the dosimetric features of SS and a linear function of applied dose described best the dose-response data obtained for stable species, that is, radical B, in the dose range of 0-10 kGy. An accuracy of 4% in the dose measurements was concluded to be achievable through back-projection dose calculations if SS were used as a dosimetric material. PMID:15336344

  1. Interfractional Target Variations for Partial Breast Irradiation

    SciTech Connect

    Ahunbay, Ergun E., E-mail: eahunbay@mcw.edu [Department of Radiation Oncology, Medical College of Wisconsin, Milwaukee, WI (United States); Robbins, Jared; Christian, Robert; Godley, Andrew; White, Julia; Li, X. Allen [Department of Radiation Oncology, Medical College of Wisconsin, Milwaukee, WI (United States)

    2012-04-01

    Purpose: In this work, we quantify the interfractional variations in the shape of the clinical target volume (CTV) by analyzing the daily CT data acquired during CT-guided partial breast irradiation (PBI) and compare the effectiveness of various repositioning alignment strategies considered to account for the variations. Methods and Materials: The daily CT data for 13 breast cancer patients treated with PBI in either prone (10 patients) or supine (3 patients) with daily kV CT guidance using CT on Rails (CTVision, Siemens, Malvern, PA) were analyzed. For approximately 25 points on the surface of the CTV, deformation vectors were calculated by means of deformable image registration and verified by visual inspection. These were used to calculate the distances along surface normals (DSN), which directly related to the required margin expansions for each point. The DSN values were determined for seven alignment methods based on volumetric imaging and also two-dimensional projections (portal imaging). Results: The margin expansion necessary to cover 99% of all points for all days was 2.7 mm when utilizing the alignment method based on deformation field data (the best alignment method). The center-of-mass based alignment yielded slightly worse results (a margin of 4.0 mm), and shifts obtained by operator placement (7.9 mm), two-dimensional-based methods (7.0-10.1 mm), and skin marks (13.9 mm) required even larger margin expansions. Target shrinkage was evident for most days by the negative values of DSN. Even with the best alignment, the range of DSN values could be as high as 7 mm, resulting in a large amount of normal tissue irradiation, unless adaptive replanning is employed. Conclusion: The appropriate alignment method is important to minimize the margin requirement to cover the significant interfractional target deformations observed during PBI. The amount of normal tissue unnecessarily irradiated is still not insignificant, and can be minimized if adaptive radiotherapy is applied.

  2. Control of fouling formation in membrane ultrafiltration by ultrasound irradiation.

    PubMed

    Naddeo, Vincenzo; Belgiorno, Vincenzo; Borea, Laura; Secondes, Mona Freda N; Ballesteros, Florencio

    2015-05-01

    The increasing application of membrane filtration in water and wastewater treatment necessitates techniques to improve performance, especially in fouling control. Ultrasound is one promising technology for this purpose as cavitational effects facilitate continuous cleaning of the membrane. This research studied the ultrafiltration of lake water in systems with constant permeate flux under medium frequency (45?kHz) ultrasound irradiation. Fouling was investigated by monitoring transmembrane pressure (TMP) using continuous or intermittent ultrasound irradiation and dead-end or crossflow operation. Best performance was observed with continuous ultrasound irradiation in crossflow mode. Intermittent irradiation reduced the rate of TMP build-up but nevertheless allowed irreversible fouling to develop. PMID:25384626

  3. Health protection and food preservation by gamma irradiation

    NASA Technical Reports Server (NTRS)

    1976-01-01

    Results of several major studies on food systems for space missions beginning with Apollo 12 through Apollo-Soyuz and investigations of the application of irradiation to food for manned space flight are reported. The study of flight food systems involved the application of radurization (pasteurizing levels) doses of gamma irradiation to flour and bread supplied by Pepperidge Farms in advance of the missions. All flights from Apollo 12 through 17 carried irradiated fresh bread. On Apollo 17, cooperation with Natick Laboratories permitted the introduction of a ham sandwich using irradiated bread and irradiated sterile ham. Investigations centered on irradiated bread were conducted during the course of these missions. Studies were applied to the concept of improving fresh bread from the point of view of mold inhibition. The studies considered how irradiation could best be applied at what levels and on a variety of bread types. Throughout the studies of the application of gamma irradiation the emphasis was placed upon using low levels of irradiation in the pasteurizing or radurizing doses--under a Megarad. The primary goal was to determine if a public health benefit could be demonstrated using radurization along with food preservation and food quality improvements. The public health benefit would be parallel to that of pasteurization of milk as a concept. Publications are included providing the details of these observations, one dealing with the flour characteristics and the other dealing with the influence on fresh bread types. These demonstrate the major findings noted during the period of the studies examining bread.

  4. Antimicrobial properties of natural substances in irradiated fresh poultry

    NASA Astrophysics Data System (ADS)

    Mahrour, A.; Lacroix, M.; Nketsa-Tabiri, J.; Calderon, N.; Gagnon, M.

    1998-06-01

    This study was undertaken to determine if a combined treatment (marinating in natural plant extracts or vacuum) with irradiation could have a synergetic effect, in order to reduce the dose required for complete elimination of Salmonella on fresh poultry. The effect of these combined treatments on the shelf-life extension was also evaluated. The fresh chicken legs were irradiated at 0, 3 and 5 kGy. The poultry underwent microbial analysis(mesophilic and Salmonella detection). For each treatment, the total microbial count decreased with increase of irradiation dose. The marinating treatment have a synergistic effect with irradiation treatment to reduce the total microbial count and controlling the proliferation during storage at 4°C. Irradiation of fresh chicken pieces with a dose of 3 kGy appears to be able to extend the microbial shelf-life by a factor of 2. When the chicken is marinating and irradiated at 3 kGy or when irradiated at 5 kGy without marinating, the microbial shelf-life is extended by a factor of 7 to 8. No Salmonella was found during all the experiment in the chicken in air and marinated. However, a presence of Salmonella was found in samples irradiated at 5 kGy under vacuum, in unirradiated samples and samples irradiated at 3kGy in air and under vacuum.

  5. Effect of gamma-irradiation on degradation of alginate.

    PubMed

    Lee, Dong Wook; Choi, Won Seok; Byun, Myung Woo; Park, Hyun Jin; Yu, Yong-Man; Lee, Chong M

    2003-07-30

    The aqueous solution of alginate was irradiated by 60Co gamma-rays in the dose range of 10-500 kGy. To assess the effect of irradiation on the degradation of alginate, the irradiation-induced changes in the viscosity, molecular weight, color, monomer composition, and sequence were measured. The molecular weight of raw alginate was reduced from 300000 to 25000 when irradiated at 100 kGy. The degradation rate decreased and the chain breaks per molecule increased with increasing irradiation dose. The viscosity of irradiated alginate solution reached a near minimum as low as at 10 kGy. No appreciable color changes were observed in the samples irradiated at up to 100 kGy, but intense browning occurred beyond 200 kGy. The 13C NMR spectra showed that homopolymeric blocks, MM and GG, increased and the M/G ratio decreased with irradiation. Considering both the level of degradation and the color change of alginate, the optimum irradiation dose was found to be 100 kGy. PMID:14705918

  6. Study on sterilization and storage of enzymatic preparations by irradiation

    NASA Astrophysics Data System (ADS)

    Dengyi, Xu; Guangzheng, Liu; Yunsen, Long; Xiaoping, Liu; Fengxin, Yi; Xiaqdong, Zhao

    1993-10-01

    Effects of irradiation with cobalt-60 ?-rays on sterilization, storage and enzymes activity of four kinds of biological enzymatic preparations, namely trypsin, pepsin, amylase and liquid carbohydrase, were investigated. The results showed that these enzymes have different sensitivity to irradiation, amylase being the most sensitive. The enzyme activity and enzyme effect of amylase were lowered with irradiation dose higher than 7 KGY. With irradiation doses between 7-10 KGY, enzyme activity of trypsin and pepsin were stable. Liquid carbohydrase can be stored more than half a year under a natural temperature with a stable enzyme activity without molding.

  7. Revascularization of autogenous skin grafts placed on irradiated tissue

    SciTech Connect

    Ueda, M.; Torii, S.; Kaneda, T.; Oka, T.

    1982-08-01

    Vascular changes in rat skin after irradiation were examined microangiographically. Revascularization of the skin transplanted during the chronic stage after irradiation was also studied. The results obtained through these examinations revealed higher vascular densities at the acute and the subacute stages, and low values at the chronic stages compared with those of the control. Furthermore, when the skin grafts were transplanted to the irradiated beds in the chronic stage, primary revascularization was scant, and the inhibited capillary proliferation in the recipient sites prevented new vessel penetration. This explains why grafts transplanted to previously irradiated beds fail to survive.

  8. Amorphous molecular junctions produced by ion irradiation on carbon nanotubes

    NASA Astrophysics Data System (ADS)

    Wang, Zhenxia; Yu, Liping; Zhang, Wei; Ding, Yinfeng; Li, Yulan; Han, Jiaguang; Zhu, Zhiyuan; Xu, Hongjie; He, Guowei; Chen, Yi; Hu, Gang

    2004-04-01

    Experiments and molecular dynamics have demonstrated that electron irradiation could create molecular junctions between crossed single-wall carbon nanotubes. Recently molecular dynamics computation predicted that ion irradiation could also join single-walled carbon nanotubes. Employing carbon ion irradiation on multi-walled carbon nanotubes, we find that these nanotubes evolve into amorphous carbon nanowires, more importantly, during the process of which various molecular junctions of amorphous nanowires are formed by welding from crossed carbon nanotubes. It demonstrates that ion-beam irradiation could be an effective way not only for the welding of nanotubes but also for the formation of nanowire junctions.

  9. Emulation of reactor irradiation damage using ion beams

    SciTech Connect

    G. S. Was; Z. Jiao; E. Beckett; A. M. Monterrosa; O. Anderoglu; B. H. Sencer; M. Hackett

    2014-10-01

    The continued operation of existing light water nuclear reactors and the development of advanced nuclear reactor depend heavily on understanding how damage by radiation to levels degrades materials that serve as the structural components in reactor cores. The first high dose ion irradiation experiments on a ferritic-martensitic steel showing that ion irradiation closely emulates the full radiation damage microstructure created in-reactor are described. Ferritic-martensitic alloy HT9 (heat 84425) in the form of a hexagonal fuel bundle duct (ACO-3) accumulated 155 dpa at an average temperature of 443°C in the Fast Flux Test Facility (FFTF). Using invariance theory as a guide, irradiation of the same heat was conducted using self-ions (Fe++) at 5 MeV at a temperature of 460°C and to a dose of 188 displacements per atom. The void swelling was nearly identical between the two irradiations and the size and density of precipitates and loops following ion irradiation are within a factor of two of those for neutron irradiation. The level of agreement across all of the principal microstructure changes between ion and reactor irradiations establishes the capability of tailoring ion irradiations to emulate the reactor-irradiated microstructure.

  10. Proton irradiation of malignant melanoma of the ciliary body.

    PubMed Central

    Gragoudas, E S; Goitein, M; Koehler, A; Wagner, M S; Verhey, L; Tepper, J; Suit, H D; Schneider, R J; Johnson, K N

    1979-01-01

    This is our first case of malignant melanoma of the ciliary body treated with proton beam irradiation, a technique that we developed for irradiating choroidal melanomas. After 21 months of follow-up no growth of the tumour has been observed, and shrinkage of the tumour was noted on the follow-up photographs and by ultrasonography. The 32P uptake test, which was positive before treatment, turned negative 14 months after irradiation. The described technique of proton beam irradiation might offer an alternative for the treatment of ciliary body melanomas when the present techniques of iridocyclectomy cannot be applied because of the size of the lesion. Images PMID:106873

  11. Preparation and characterization of DNA films induced by UV irradiation.

    PubMed

    Yamada, Masanori; Kato, Kozue; Nomizu, Motoyoshi; Sakairi, Nobuo; Ohkawa, Kousaku; Yamamoto, Hiroyuki; Nishi, Norio

    2002-03-15

    Large amounts of DNA-enriched materials, such as salmon milts and shellfish gonads, are discarded as industrial waste. We have been able to convert the discarded DNA to a useful material by preparing novel DNA films by UV irradiation. When DNA films were irradiated with UV light, the molecular weight of DNA was greatly increased. The reaction was inhibited by addition of the radical scavenger galvinoxyl suggesting that the DNA polymerization with UV irradiation proceeded by a radical reaction. Although this UV-irradiated DNA film was water-insoluble and resistant to hydrolysis by nuclease, the structure of the DNA film in water was similar to non-irradiated DNA and maintained B-form structure. In addition, the UV-irradiated DNA film could effectively accumulate and condense harmful DNA-intercalating compounds, such as ethidium bromide and acridine orange, from diluted aqueous solutions. The binding constant and exclusion number of ethidium bromide for UV-irradiated DNA were determined to be 6.8 +/- 0.3 x 10(4) M(-1) and 1.6 +/- 0.2, respectively; these values are consisted with reported results for non-irradiated DNA. The UV-irradiated DNA films have potential uses as a biomaterial filter for the removal of harmful DNA intercalating compounds. PMID:11921224

  12. Pretransfusion blood irradiation: Clinical rationale and dosimetric considerations

    SciTech Connect

    Masterson, M.E.; Febo, R. (Department of Medical Physics, Memorial Sloan-Kettering Cancer Center, 1275 York Avenue, New York 10021 (United States))

    1992-05-01

    The irradiation of blood before transfusion into immunosuppressed patients is an increasingly common technique used to prevent graft-versus-host disease. A technical procedure is described for the calibration of blood irradiators, including the determination of absolute dose rate and relative dose distribution over the blood volume. Results of dose rate measurements on commercially available irradiators indicate differences of +5% to {minus}13% with manufacturer-supplied calibrations and variations in the relative dose rate over the irradiation volume from 70% to 180%. The clinical implications of these findings and the need for accurate dosimetry are discussed.

  13. Practical dosimetric aspects of blood and blood product irradiation

    SciTech Connect

    Fearon, T.C.; Luban, N.L.

    1986-09-01

    The method of choice to reduce susceptibility to transfusion-transmitted graft-versus-host disease is irradiation of allogenic blood and blood products for transfusion to immunosuppressed recipients. Optimal irradiation requires delivery of a known and homogeneous absorbed dose. The use of absorbed dose in air measured at the center of the irradiation volume without proper compensation for sample absorption can lead to approximately 20 percent underexposure. A lucite cylinder was used to provide the delivery of a homogeneous irradiation dose to blood products of different volumes by allowing rotation of the product.

  14. EPR study on gamma-irradiated fruits dehydrated via osmosis

    NASA Astrophysics Data System (ADS)

    Yordanov, N. D.; Aleksieva, K.

    2007-06-01

    The shape and time stability of the electron paramagnetic resonance (EPR) spectra of non- and ?-irradiated papaya, melon, cherry and fig samples dehydrated via osmosis are reported. It is shown that non-irradiated samples are generally EPR silent whereas ?-irradiated exhibit "sugar-like" EPR spectra. The recorded EPR spectra are monitored for a period of 7 months after irradiation (stored at low humidity and in the dark). The results suggest longer period of unambiguous identification of the radiation processing of osmose dehydrated fruits. Therefore, the Protocol EN 13708,2001 issued by CEN is fully applicable for the studied fruit samples.

  15. Gamma irradiation reduces the immunological toxicity of doxorubicin, anticancer drug

    NASA Astrophysics Data System (ADS)

    Kim, Jae-Hun; Sung, Nak-Yun; Raghavendran, H. Balaji; Yoon, Yohan; Song, Beom-Seok; Choi, Jong-il; Yoo, Young-Choon; Byun, Myung-Woo; Hwang, Young-Jeong; Lee, Ju-Woon

    2009-07-01

    Doxorubicin (DOX) is a widely used anticancer agent, but exhibits some immunological toxicity to patients during chemotherapy. The present study was conducted to evaluate the effect of gamma irradiation on the immunological response and the inhibition activity on in vivo tumor mass of DOX. The results showed that DOX irradiated at 10 and 20 kGy reduce the inhibition of mouse peritoneal macrophage proliferation and induce the release of cytokines (TNF-? and IL-6) when compared with non-irradiated DOX. The cytotoxicity against human breast (MCF-7), murine colon adenocarcinoma (Colon 26) and human monocytic (THP-1) tumor cell were not significantly different between non-irradiated and irradiated DOX ( P<0.05). In vivo study on the tumor mass inhibition, gamma-irradiated DOX showed a considerable inhibition of tumor mass and this effect was statistically non-significant as compared with non-irradiated DOX. In conclusion, gamma irradiation could be regarded as a potential method for reducing the immunological toxicity of DOX. Further researches is needed to reveal the formation and activity of radiolysis products by gamma irradiation.

  16. Food irradiation in Hungary: commercial processing and development work

    NASA Astrophysics Data System (ADS)

    Kalman, B.; Szikra, L.; Ferencz, P.

    2000-03-01

    The result of an experiment with irradiated frozen poultry meat is presented. The purpose of the experiment was to prove the benefit of irradiation treatment for elimination of pathogenic bacteria such as Salmonella and Campylobacter. We found that an average dose of 4.5 kGy kills the bacteria in the meat. Agroster was involved in an EU project on the identification of irradiation treatment of spices and data from this project are presented. Commercial irradiation of spices has been used for more than 15 years in Hungary, proving the benefit of this technology

  17. Radicals in {gamma}-irradiated wool

    SciTech Connect

    Baeva, N.N.; Sadova, S.F.; Sharpatyi, V.A.

    1992-01-01

    Radicals were identified in wool fiber {gamma}-irradiated at 77 K by EPR: products of reaction of an electron e and H atom with amino acid residues and a polypeptide chain, and their partial yields at 77 K and the reactivity scale of e with respect to the individual fragments of the protein molecule were determined: [RSSR]: [>C=O{sub p.b.}]:[NH{sub 3}{sup +}-R]:[aromatic ring] = 4:3: > 1:1. 10 refs., 1 fig., 1 tab.

  18. Medical waste irradiation study. Final report

    SciTech Connect

    Adler, R.J.; Stein, J. [North Star Research Corp., Albuquerque, NM (United States); Nygard, J. [Advance Bio-Control (United States)

    1998-07-25

    The North Star Research Corporation Medical Waste project is described in this report, with details of design, construction, operation, and results to date. The project began with preliminary design of the accelerator. The initial design was for a single accelerator chamber with a vacuum tube cavity driver built into the chamber itself, rather than using a commercial tube separate from the RF accelerator. The authors believed that this would provide more adjustability and permit better coupling to be obtained. They did not have sufficient success with that approach, and finally completed the project using a DC accelerator with a unique new scanning system to irradiate the waste.

  19. Total skin electron irradiation techniques: a review

    PubMed Central

    Milecki, Piotr; Skórska, Ma?gorzata; Fundowicz, Dorota

    2013-01-01

    Total skin electron irradiation (TSEI) has been employed as one of the methods of mycosis fungoides treatment since the mid-twentieth century. In order to improve the effects and limit the complications following radiotherapy, a number of varieties of the TSEI method, frequently differing in the implementation mode have been developed. The paper provides a systematic review of the different varieties of TSEI. The discussed differences concerned especially: (i) technological requirements and geometric conditions, (ii) the alignment of the patient, (iii) the number of treatment fields, and (iv) dose fractionation scheme. PMID:24278046

  20. Effect of irradiation spectrum on the microstructure of ion-irradiated Al{sub 2}O{sub 3}

    SciTech Connect

    Zinkle, S.J. [Oak Ridge National Lab., TN (United States). Metals and Ceramics Div.

    1994-12-31

    Polycrystalline samples of alpha-alumina have been irradiated with various ions ranging from 3.6 MeV Fe{sup +} to 1 MeV H{sup +} ions at 650 C. Cross-section transmission electron microscopy was used to investigate the depth-dependent microstructure of the irradiated specimens. The microstructure following irradiation was observed to be dependent on the irradiation spectrum. In particular, defect cluster nucleation was effectively suppressed in specimens irradiated with light ions such as 1 MeV H{sup +} ions. On the other hand, light ion irradiation tended to accelerate the growth rate of dislocation loops. The microstructural observations are discussed in terms of ionization enhanced diffusion processes.

  1. Modeling daylight availability and irradiance components from direct and global irradiance

    Microsoft Academic Search

    R. Perez; P. Ineichen; R. Seals; J. Michalsky; R. Stewart

    1990-01-01

    This paper presents the latest versions of several models developed by the authors to predict short time-step solar energy and daylight availability quantities needed by energy system modelers or building designers. The modeled quantities are global, direct and diffuse daylight illuminance, diffuse irradiance and illuminance impinging on tilted surfaces of arbitrary orientation, sky zenith luminance and sky luminance angular distribution.

  2. Irradiation dose detection of irradiated milk powder using visible and near-infrared spectroscopy and chemometrics.

    PubMed

    Kong, W W; Zhang, C; Liu, F; Gong, A P; He, Y

    2013-08-01

    The objective of this study was to examine the possibility of applying visible and near-infrared spectroscopy to the quantitative detection of irradiation dose of irradiated milk powder. A total of 150 samples were used: 100 for the calibration set and 50 for the validation set. The samples were irradiated at 5 different dose levels in the dose range 0 to 6.0 kGy. Six different pretreatment methods were compared. The prediction results of full spectra given by linear and nonlinear calibration methods suggested that Savitzky-Golay smoothing and first derivative were suitable pretreatment methods in this study. Regression coefficient analysis was applied to select effective wavelengths (EW). Less than 10 EW were selected and they were useful for portable detection instrument or sensor development. Partial least squares, extreme learning machine, and least squares support vector machine were used. The best prediction performance was achieved by the EW-extreme learning machine model with first-derivative spectra, and correlation coefficients=0.97 and root mean square error of prediction=0.844. This study provided a new approach for the fast detection of irradiation dose of milk powder. The results could be helpful for quality detection and safety monitoring of milk powder. PMID:23769357

  3. YANKEE IRRADIATION PROGRAM. SUMMARY REPORT, PART I. YANKEE INPILE LOOP IRRADIATION TEST

    Microsoft Academic Search

    Bullington

    1962-01-01

    An in-pile loop test program is described for evaluation of stainless ; steel-clad UOâ behavior in pressurized water at 600 deg F under irradiation. ; The corrosion behavior of Zircaloy-2, 304 stainless steel, and Ag-In-Cd control ; rod material was also tested in a similar environment. The hideout behavior of ; lithiated boric acid at Yankee operating conditions of temperature,

  4. Irradiation-induced effects of proton irradiation on zirconium carbides with different stoichiometries

    SciTech Connect

    Y. Huang; B.R. Maier; T.R. Allen

    2014-10-01

    Zirconium carbide (ZrC) is being considered for utilization in deep burn TRISO fuel particles for hightemperature, gas-cooled reactors. Zirconium carbide has a cubic B1 type crystal structure along with a very high melting point (3420 ?C), exceptional hardness and good thermal and electrical conductivities. Understanding the ZrC irradiation response is crucial for establishing ZrC as an alternative component in TRISO fuel. Until now, very few studies on irradiation effects on ZrC have been released and fundamental aspects of defect evolution and kinetics are not well understood although some atomistic simulations and phenomenological studies have been performed. This work was carried out to understand the damage evolution in float-zone refined ZrC with different stoichiometries. Proton irradiations at 800 ?C up to doses of 3 dpa were performed on ZrCx (where x ranges from 0.9 to 1.2) to investigate the damage evolution. The irradiation-induced defects, such as density of dislocation loops, at different stoichiometries and doses which were characterized by transmission electron microscopy (TEM) is presented and discussed.

  5. In-situ high temperature irradiation setup for temperature dependent structural studies of materials under swift heavy ion irradiation

    NASA Astrophysics Data System (ADS)

    Kulriya, P. K.; Kumari, Renu; Kumar, Rajesh; Grover, V.; Shukla, R.; Tyagi, A. K.; Avasthi, D. K.

    2015-01-01

    An in-situ high temperature (1000 K) setup is designed and installed in the materials science beam line of superconducting linear accelerator at the Inter-University Accelerator Centre (IUAC) for temperature dependent ion irradiation studies on the materials exposed with swift heavy ion (SHI) irradiation. The Gd2Ti2O7 pyrochlore is irradiated using 120 MeV Au ion at 1000 K using the high temperature irradiation facility and characterized by ex-situ X-ray diffraction (XRD). Another set of Gd2Ti2O7 samples are irradiated with the same ion beam parameter at 300 K and simultaneously characterized using in-situ XRD available in same beam line. The XRD studies along with the Raman spectroscopic investigations reveal that the structural modification induced by the ion irradiation is strongly dependent on the temperature of the sample. The Gd2Ti2O7 is readily amorphized at an ion fluence 6 × 1012 ions/cm2 on irradiation at 300 K, whereas it is transformed to a radiation-resistant anion-deficient fluorite structure on high temperature irradiation, that amorphized at ion fluence higher than 1 × 1013 ions/cm2. The temperature dependent ion irradiation studies showed that the ion fluence required to cause amorphization at 1000 K irradiation is significantly higher than that required at room temperature irradiation. In addition to testing the efficiency of the in-situ high temperature irradiation facility, the present study establishes that the radiation stability of the pyrochlore is enhanced at higher temperatures.

  6. Allograft tolerance in pigs after fractionated lymphoid irradiation. I. Skin grafts after partial lateral irradiation and bone marrow cell grafting

    SciTech Connect

    Vaiman, M.; Daburon, F.; Remy, J.; Villiers, P.A.; de Riberolles, C.; Lecompte, Y.; Mahouy, G.; Fradelizi, D.

    1981-05-01

    Experiments with pigs have been performed to establish bone marrow chimerism and skin graft tolerance between SLA genotyped animals. Recipients were conditioned by means of fractionated partial irradiation from lateral cobalt sources (partial lateral irradiation (PLI)). The head, neck, and lungs were protected with lead, the rest of the body being irradiated including the thymus, the majority of lymphoid organs with spleen, and most of the bone marrow sites.

  7. The hematological response and survival of acutley irradiated rats previously exposed to continuous and fractionated, low intensity gamma irradiation

    E-print Network

    Hooper, John Anderson

    1964-01-01

    cylindex' to the center of tho snnulsx source, where they were subjected to gamma raya at s rate of 710 r per minute Bach animal waa restrained in a polyethylene carton during the irradiation. A description of this irradiation facility is also included... the full 52 days postirradiatien had an average bone marrow lymphocyte lovel of 26. 5 per cent (eight animals). individuals which succombed very early after acute irradiation were fouad to possess few cells (including lymphocytes) of any discernable typo...

  8. La production industrielle sous la IVe République

    Microsoft Academic Search

    Michel Catinat

    1981-01-01

    [fre] A partir d'un instrument nouveau, les comptes trimestriels de la période 1946-1962, cet article essaie de décrire les fluctuations économiques du système productif pendant la quatrième république. Il est centré uniquement sur les branches énergétiques (combustibles minéraux solides et gaz, électricité, pétrole, gaz naturel et carburants) et sur les branches industrielles (mines de fer et sidérurgie, minerais et métaux

  9. Irradiation hardening of ODS ferritic steels under helium implantation and heavy-ion irradiation

    NASA Astrophysics Data System (ADS)

    Zhang, Hengqing; Zhang, Chonghong; Yang, Yitao; Meng, Yancheng; Jang, Jinsung; Kimura, Akihiko

    2014-12-01

    Irradiation hardening of ODS ferritic steels after multi-energy He-ion implantation, or after irradiation with energetic heavy ions including Xe and Bi-ions was investigated with nano-indentation technique. Three kinds of high-Cr ODS ferritic steels including the commercial MA956 (19Cr-3.5Al), the 16Cr-0.1Ti and the 16Cr-3.5Al-0.1Zr were used. Data of nano-hardness were analyzed with an approach based on Nix-Gao model. The depth profiles of nano-hardness can be understood by the indentation size effect (ISE) in specimens of MA956 implanted with multi-energy He-ions or irradiated with 328 MeV Xe ions, which produced a plateau damage profile in the near-surface region. However, the damage gradient overlaps the ISE in the specimens irradiated with 9.45 Bi ions. The dose dependence of the nano-hardness shows a rapid increase at low doses and a slowdown at higher doses. An 1/2-power law dependence on dpa level is obtained. The discrepancy in nano-hardness between the helium implantation and Xe-ion irradiation can be understood by using the average damage level instead of the peak dpa level. Helium-implantation to a high dose (7400 appm/0.5 dpa) causes an additional hardening, which is possibly attributed to the impediment of motion dislocations by helium bubbles formed in high concentration in specimens.

  10. Hafnium radioisotope recovery from irradiated tantalum

    DOEpatents

    Taylor, Wayne A. (Los Alamos, NM); Jamriska, David J. (Los Alamos, NM)

    2001-01-01

    Hafnium is recovered from irradiated tantalum by: (a) contacting the irradiated tantalum with at least one acid to obtain a solution of dissolved tantalum; (b) combining an aqueous solution of a calcium compound with the solution of dissolved tantalum to obtain a third combined solution; (c) precipitating hafnium, lanthanide, and insoluble calcium complexes from the third combined solution to obtain a first precipitate; (d) contacting the first precipitate of hafnium, lanthanide and calcium complexes with at least one fluoride ion complexing agent to form a fourth solution; (e) selectively adsorbing lanthanides and calcium from the fourth solution by cationic exchange; (f) separating fluoride ion complexing agent product from hafnium in the fourth solution by adding an aqueous solution of ferric chloride to obtain a second precipitate containing the hafnium and iron; (g) dissolving the second precipitate containing the hafnium and iron in acid to obtain an acid solution of hafnium and iron; (h) selectively adsorbing the iron from the acid solution of hafnium and iron by anionic exchange; (i) drying the ion exchanged hafnium solution to obtain hafnium isotopes. Additionally, if needed to remove residue remaining after the product is dried, dissolution in acid followed by cation exchange, then anion exchange, is performed.

  11. A Simplified Shuttle Irradiation Facility for ATR

    SciTech Connect

    A. J. Palmer; S. T. Laflin

    1999-08-01

    During the past fifteen years there has been a steady increase in the demand for radioisotopes in nuclear medicine and a corresponding decline in the number of reactors within the U.S. capable of producing them. The Advanced Test Reactor (ATR) is the largest operating test reactor in the U.S., but its isotope production capabilities have been limited by the lack of an installed isotope shuttle irradiation system. A concept for a simple "low cost" shuttle irradiation facility for ATR has been developed. Cost were reduced (in comparison to previous ATR designs) by using a shielded trough of water installed in an occupiable cubicle as a shielding and contamination control barrier for the send and receive station. This shielding concept also allows all control valves to be operated by hand and thus the need for an automatic control system was eliminated. It was determined that 4-5 ft of water would be adequate to shield the isotopes of interest while shuttles are transferred to a small carrier. An additional feature of the current design is a non-isolatable by-pass line, which provides a minimum coolant flow to the test region regardless of which control valves are opened or closed. This by-pass line allows the shuttle facility to be operated without bringing reactor coolant water into the cubicle except for send and receive operations.

  12. Phytosanitary irradiation of Liriomyza trifolii (Diptera: Agromyzidae).

    PubMed

    Hallman, Guy J; Guo, Kun; Liu, Tong-Xian

    2011-12-01

    Agromyzid leafminers are economic and quarantine pests of a variety of vegetables, flowers, and ornamental foliage. Methyl bromide fumigation is often used as a phytosanitary treatment when quarantined agromyzids are found in shipped commodities; alternative treatments are sought. Ionizing radiation is a viable alternative that is increasing in use worldwide. A dose of 400 Gy is accepted by USDA-APHIS for all insects (except Lepidoptera pupae and adults) on all commodities. Efforts to lower this dose and make it acceptable to other countries involve determining radiotolerance of families of major quarantine pests. Agromyzidae is one such family for which no useful information on radiotolerance exists. This research sought to determine the dose required to control a major agromyzid pest, Liriomyza trifolii (Burgess) and was performed on L. trifolii collected in Weslaco, TX, reared on Phaseolus vulgaris L. and Capsicum annuum L. and irradiated in the late puparial stage. The measure of efficacy was prevention of F1 mine formation. Puparia collected from Gossypium hirsutum L. and reared on P. vulgaris were more radiotolerant than those collected and reared on C. annuum. A dose of 214 Gy may prevent F1 mine formation of L. trifolii. This research used a variation of probit analysis where the direct response of the treated individual is not measured, but the response of the F1 generation is. This type of analysis is useful in phytosanitary irradiation research where the measure of efficacy often involves a response of the F1 generation. PMID:22299344

  13. Heat profiles of laser-irradiated nails.

    PubMed

    Paasch, Uwe; Nenoff, Pietro; Seitz, Anna-Theresa; Wagner, Justinus A; Kendler, Michael; Simon, Jan C; Grunewald, Sonja

    2014-01-01

    Onychomycosis is a worldwide problem with no tendency for self-healing, and existing systemic treatments achieve disease-free nails in only 35 to 76% of cases. Recently, treatment of nail fungus with a near-infrared laser has been introduced. It is assumed that fungal eradication is mediated by local heat. To investigate if laser treatment has the potential to eradicate fungal hyphae and arthrospores, laser heat application and propagation needs to be studied in detail. This study aimed to measure nail temperatures using real-time videothermography during laser irradiation. Treatment was performed using 808- and 980-nm linear scanning diode lasers developed for hair removal, enabling contact-free homogeneous irradiation of a human nail plate in one pass. Average and peak temperatures increased pass by pass, while the laser beam moved along the nail plates. The achieved mean peak temperatures (808 nm: 74.1 to 112.4°C, 980 nm: 45.8 to 53.5°C), as well as the elevation of average temperatures (808 nm: 29.5 to 38.2°C, 980 nm: 27.1 to 32.6°C) were associated with pain that was equivalent to that of hair removal procedures and was not significantly different for various wavelengths. The linear scanning laser devices provide the benefits of contact-free homogeneous heating of the human nail while ensuring adequate temperature rises. PMID:24407504

  14. Evolution of defect cluster distributions during irradiation

    SciTech Connect

    Wiedersich, H.

    1991-05-01

    Defects produced by irradiation are often strongly spatially correlated. Energetic primary recoil atoms produce cascades with vacant lattice sites predominantly in the central regions, and interstitial atoms at the periphery. A fraction of the defects produced form clusters during cascade events. Because of their spatial distribution more mobile interstitial atoms than vacancies are released into the matrix following the cascade events. Populations of vacancy and interstitial clusters evolve towards quasi-steady-state distributions. As long as vacancy clusters are thermally moderately stable, i.e., at temperatures below rapid self diffusion, an excess interstitial flux persists in the matrix; as a consequence, vacancy clusters formed in cascades shrink, and interstitial clusters grow. We examine the evolution of these cluster distributions, and their effects on sink strength and radiation-enhanced diffusion, as function of dose for irradiations at moderate temperatures. At temperatures at which thermal evaporation from vacancy clusters, can be neglected, the evolution of the cluster densities is characteristic of the primary recoil spectrum, but is independent of temperature or dose rate. The sink strength, radiation-enhanced diffusion, as well as other consequences of the evolving distributions such as the imbalance of the interstitial and vacancy fluxes in the matrix, approach slowly-changing quasi-steady-state values in a fraction of one displacement per atom, although certain details of the cluster distributions, e.g., the development of large interstitial loops, require several dpa's to approach steady state values. 22 refs., 6 figs.

  15. Absorption spectra of irradiated XRCT radiochromic film.

    PubMed

    Butson, Martin J; Cheung, Tsang; Yu, Peter K N

    2006-06-21

    Gafchromic XRCT radiochromic film is a self-developing high sensitivity radiochromic film product which can be used for assessment of delivered radiation doses which could match applications such as computed tomography (CT) dosimetry. The film automatically changes colour upon irradiation changing from a yellow to green/brown colour. The absorption spectra of Gafchromic XRCT radiochromic film as measured with reflectance spectrophotometry have been investigated to analyse the dosimetry characteristics of the film. Results show two main absorption peaks produced from irradiation located at 636 nm and 585 nm. This is similar to EBT Gafchromic film. A high level of sensitivity is found for this film with a 1 cGy applied dose producing an approximate net optical density change of 0.3 at 636 nm. This high sensitivity combined with its relatively energy independent nature around the 100 kVp to 150 kVp x-ray energy range provides a unique enhancement in dosimetric measurement capabilities over currently available dosimetry films for CT applications. PMID:16757865

  16. Absorption spectra of irradiated XRCT radiochromic film

    NASA Astrophysics Data System (ADS)

    Butson, Martin J.; Cheung, Tsang; Yu, Peter K. N.

    2006-06-01

    Gafchromic XRCT radiochromic film is a self-developing high sensitivity radiochromic film product which can be used for assessment of delivered radiation doses which could match applications such as computed tomography (CT) dosimetry. The film automatically changes colour upon irradiation changing from a yellow to green/brown colour. The absorption spectra of Gafchromic XRCT radiochromic film as measured with reflectance spectrophotometry have been investigated to analyse the dosimetry characteristics of the film. Results show two main absorption peaks produced from irradiation located at 636 nm and 585 nm. This is similar to EBT Gafchromic film. A high level of sensitivity is found for this film with a 1 cGy applied dose producing an approximate net optical density change of 0.3 at 636 nm. This high sensitivity combined with its relatively energy independent nature around the 100 kVp to 150 kVp x-ray energy range provides a unique enhancement in dosimetric measurement capabilities over currently available dosimetry films for CT applications.

  17. Heat profiles of laser-irradiated nails

    NASA Astrophysics Data System (ADS)

    Paasch, Uwe; Nenoff, Pietro; Seitz, Anna-Theresa; Wagner, Justinus A.; Kendler, Michael; Simon, Jan C.; Grunewald, Sonja

    2014-01-01

    Onychomycosis is a worldwide problem with no tendency for self-healing, and existing systemic treatments achieve disease-free nails in only 35 to 76% of cases. Recently, treatment of nail fungus with a near-infrared laser has been introduced. It is assumed that fungal eradication is mediated by local heat. To investigate if laser treatment has the potential to eradicate fungal hyphae and arthrospores, laser heat application and propagation needs to be studied in detail. This study aimed to measure nail temperatures using real-time videothermography during laser irradiation. Treatment was performed using 808- and 980-nm linear scanning diode lasers developed for hair removal, enabling contact-free homogeneous irradiation of a human nail plate in one pass. Average and peak temperatures increased pass by pass, while the laser beam moved along the nail plates. The achieved mean peak temperatures (808 nm: 74.1 to 112.4°C, 980 nm: 45.8 to 53.5°C), as well as the elevation of average temperatures (808 nm: 29.5 to 38.2°C, 980 nm: 27.1 to 32.6°C) were associated with pain that was equivalent to that of hair removal procedures and was not significantly different for various wavelengths. The linear scanning laser devices provide the benefits of contact-free homogeneous heating of the human nail while ensuring adequate temperature rises.

  18. Solar variability in irradiance and oscillations

    NASA Technical Reports Server (NTRS)

    Kuhn, Jeff R.

    1995-01-01

    The signature of the solar cycle appears in helioseismic frequencies and splittings. It is known that the changing outer superadiabatic region of the sun is responsible for this. The deeper solar-cycle mechanism from the surface changes, and, in particular, how magnetic fields perturb the global modes, the solar irradiance and the luminosity, is discussed. The irradiance and helioseismic changes are described. The interpretation of seismic and photometric data is discussed, considering current one-dimensional models and phenomenology. It is discussed how the long term solar-cycle luminosity effect could be caused by changes occurring near the base of the convection zone (CZ). It is shown that a thin toroidal flux sheath at the top of the radiative zone changed the thermal stratification immediately below the CZ over a solar-cycle timescale in two ways: the temperature of the magnetized fluid becomes hotter than the surrounding fluid, and the temperature gradient steepens above the magnetized region. The testing of CZ dynamics and extension of numerical experiments to global scales are considered.

  19. LISIRD: LASP Interactive Solar Irradiance Data Center

    NASA Astrophysics Data System (ADS)

    Lindholm, D. M.; Wilson, A.

    2013-12-01

    The Laboratory for Atmospheric and Space Physics (LASP) at the University of Colorado Boulder has been involved in numerous space-borne missions to directly measure and understand the variability of the Sun's energy output and its impact on global climate change. The LASP Interactive Solar Irradiance Data Center (LISIRD) provides a web site with interactive graphics to explore, subset, and download these and other solar related datasets. The LISIRD collections include observations of total and spectral irradiance with coverage from the X-ray to the infrared from projects such as SME, UARS SOLSTICE, SNOE, TIMED SEE, SORCE, and SDO EVE plus a growing number of related data products, proxies, and models. The LISIRD data services are backed by the LaTiS data server which presents a unified RESTful web service interface to slice, dice, and perform select server-side operations as the data are dynamically streamed to files of your desired format or directly into your code or analysis tools. Come see the data products and services that LISIRD has available and help us to improve them to better meet your needs.

  20. LWRS ATR Irradiation Testing Readiness Status

    SciTech Connect

    Kristine Barrett

    2012-09-01

    The Light Water Reactor Sustainability (LWRS) Program was established by the U.S. Department of Energy Office of Nuclear Energy (DOE-NE) to develop technologies and other solutions that can improve the reliability, sustain the safety, and extend the life of the current reactors. The LWRS Program is divided into four R&D Pathways: (1) Materials Aging and Degradation; (2) Advanced Light Water Reactor Nuclear Fuels; (3) Advanced Instrumentation, Information and Control Systems; and (4) Risk-Informed Safety Margin Characterization. This report describes an irradiation testing readiness analysis in preparation of LWRS experiments for irradiation testing at the Idaho National Laboratory (INL) Advanced Test Reactor (ATR) under Pathway (2). The focus of the Advanced LWR Nuclear Fuels Pathway is to improve the scientific knowledge basis for understanding and predicting fundamental performance of advanced nuclear fuel and cladding in nuclear power plants during both nominal and off-nominal conditions. This information will be applied in the design and development of high-performance, high burn-up fuels with improved safety, cladding integrity, and improved nuclear fuel cycle economics

  1. MeV Proton Irradiation Effects on Fullerenes and Graphite

    SciTech Connect

    Mathew, S. [Institute of Physics, Sachivalaya Marg, Bhubaneswar-751005 (India); Dev, B. N. [Indian Association for the Cultivation of Science, 2A and 2B Raja S. C. Mullick Road, Jadavpur, Kolkota 700 032 (India)

    2008-10-23

    Ion irradiation of graphite and other carbon allotropes is a versatile tool for manipulating their physical, chemical and even magnetic properties. Fullerene films, when irradiated with 2 MeV protons, display soft-ferromagnetic ordering at 5 K. At 300 K both pristine and irradiated films show diamagnetic behaviour.Magnetisation data in the temperature range of 2-300 K, in 1 T applied field, for the irradiated film show much stronger temperature dependence compared to a pristine film. The ion irradiation study has been further extended to the graphite system. Poly-crystalline graphite samples were irradiated with 2.25MeV protons at a fluence of 2x10{sup 17} ions/cm2.Magnetic ordering in highly oriented pyrolytic graphite samples have been reported earlier under similar irradiation conditions [Esquinazi et. al. Phys. Rev. Lett. 91 (2003) 227201]. In that study, the authors attribute the observed irradiation induced magnetic ordering to the formation of a mixed sp{sup 2}-sp{sup 3} hybridized carbon atoms. Here we present Raman and X-ray photoelectron spectroscopic studies on pristine and irradiated graphite samples. Irradiated samples are found to show an increased number of sp3 hybridized carbon atoms. However, the Raman spectrum, specially the second order data, do indicate that the nature of the graphene lattice structure has been preserved in the irradiated samples. The formation of a mixed sp{sup 2}-sp{sup 3} hybridization in graphite structure, which might be responsible for magnetism,will be discussed.

  2. Hyperbaric oxygen therapy: can it prevent irradiation-induced necrosis?

    PubMed

    Kuffler, Damien P

    2012-06-01

    Radiosurgery is an important non-invasive procedure for the treatment of tumors and vascular malformations. However, in addition to killing target tissues, cranial irradiation induces damage to adjacent healthy tissues leading to neurological deterioration in both pediatric and adult patients, which is poorly understood and insufficiently treatable. To minimize irradiation damage to healthy tissue, not the optimal therapeutic irradiation dose required to eliminate the target lesion is used but lower doses. Although the success rate of irradiation surgery is about 95%, 5% of patients suffer problems, most commonly neurological, that are thought to be a direct consequence of irradiation-induced inflammation. Although no direct correlation has been demonstrated, the appearance and disappearance of inflammation that develops following irradiation commonly parallel the appearance and disappearance of neurological side effects that are associated with the neurological function of the irradiated brain regions. These observations have led to the hypothesis that brain inflammation is causally related to the observed neurological side effects. Studies indicate that hyperbaric oxygen therapy (HBOT) applied after the appearance of irradiation-induced neurological side effects reduces the incidence and severity of those side effects. This may result from HBOT reducing inflammation, promoting angiogenesis, and influencing other cellular functions thereby suppressing events that cause the neurological side effects. However, it would be significantly better for the patient if rather than waiting for neurological side effects to become manifest they could be avoided. This review examines irradiation-induced neurological side effects, methods that minimize or resolve those side effects, and concludes with a discussion of whether HBOT applied following irradiation, but before manifestation of neurological side effects may prevent or reduce the appearance of irradiation-induced neurological side effects. PMID:22465460

  3. Source mechanisms of micro-earthquakes induced in a fluid injection experiment at the HDR site Soultz-sous-Forêts (Alsace) in 2003 and their temporal and spatial variations

    NASA Astrophysics Data System (ADS)

    Horálek, Josef; Jechumtálová, Zuzana; Dorbath, Louis; Šílený, Jan

    2010-06-01

    We have inverted the peak amplitudes of direct P waves of 45 micro-earthquakes with magnitudes between M = 1.4 and 2.9, which occurred during and after the 2003 massive fluid injection in the GPK3 borehole of the Soultz-sous-Forêts Hot Dry Rock facility. These events were recorded by a surface seismic network of 15 stations operated by the Ecole et Observatoire des Sciences de la Terre, University of Strasbourg. The unconstrained moment tensor (MT) expression of the mechanism was applied, allowing the description of a general system of dipoles, that is, both double-couple (DC) and non-DC sources, as tensile fractures. The mechanisms of all but one event are dominantly DCs with a few per cent additional components at the most. We have checked carefully the reliability of the MT retrieval in bootstrap trials eliminating some data, by simulating the mislocation of the hypocentre and by applying simplified velocity models of the area in constructing Green's functions. In some of the trials non-DC components amounting to several tens of per cent appear, but the F-test classifies them as insignificant. Even the only micro-earthquake with an exceptionally high non-DC mechanism cannot be classified unambiguously-the F-test assigns similar significance to the pure DC solution. The massive dominance of the DC indicates the shear-slip as the mechanism of the micro-earthquakes investigated. The mechanisms display large variability and are of normal dip-slip, oblique normal to strike-slip types. The T-axes are fairly stable, being concentrated subhorizontally roughly in the E-W direction. On the contrary, the P-axes are ill constrained varying in the N-S direction from nearly vertical to nearly horizontal, which points to heterogeneous stress in the Soultz injected volume. This is in agreement with the stress pattern from in situ measurements: the minimum stress axis is well constrained to E-W, whereas the maximum and intermediate stress values are close to one another, enabling the ambiguity of the P-axis direction. We found no significant dependence of source mechanisms either on magnitudes or depths. The time-space distribution of the events analysed suggests that the injection activated two segments of the natural faults existing in the area (I and II in our notation) showing different source mechanism patterns. The dip-slip regime is characteristic of fault segment I where the seismicity occurred during and also after injection, whereas the strike-slip regime prevails in segment II where the seismicity was triggered only after the injection shut in. This indicates that the tensile fractures, which are assumed to be created during injection, may have occurred on a smaller scale than the pure shear micro-earthquakes investigated.

  4. Morphological changes in the skin in response to external ?-irradiation

    Microsoft Academic Search

    F. L. Leites; N. Pospelova; I. G. Rufanov

    1959-01-01

    The author studied the changes occurring in the skin of the rabbit in external alpha-irradiation. The latter has a pronounced injurious effect, the morphological manifestations of which are analogous to those observed in the action of other types of ionizing radiation. Besides this, the reaction of the alpha-irradiated tissue has a specific feature in the form of a sharp contrast

  5. Progress of food irradiation in the United States

    Microsoft Academic Search

    Donald D. Derr

    1996-01-01

    Irradiated foods have not yet made a significant impact in the United States marketplace. Some progress has occurred, however, to make them more accessible in the marketplace. Activity in U.S. regulatory agencies and other government agencies also may be an indicator of further commercial expansion of food irradiation in the U.S. in the near future. Several regulatory agencies are involved

  6. Tropical crop quality after quarantine treatment using irradiation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Many horticultural commodites intended for export must receive an approved quarantine treatment before shipment. Irradiation is becoming an acceptable option for meeting phytosanitary requirements of fresh produce traded internationally. Irradiation at doses up to 1000 Gy have been approved by the F...

  7. ORIGIN OF THE HYDROGEN INVOLVED IN IRON CORROSION UNDER IRRADIATION

    E-print Network

    Boyer, Edmond

    1 ORIGIN OF THE HYDROGEN INVOLVED IN IRON CORROSION UNDER IRRADIATION S. Lapuertaa,b , N. Millard geological storage, high level nuclear wastes will be overpacked in low carbon steel containers % concentration range, hydrogen diffuse from the air/Fe interface through the foil an irradiation experiment

  8. Bilateral internuclear ophthalmoplegia after intrathecal chemotherapy and cranial irradiation

    SciTech Connect

    Lepore, F.E.; Nissenblatt, M.J.

    1981-12-01

    A 26-year-old man developed transient bilateral internuclear ophthalmoplegia with exotropia after cranial irradiation and intrathecal administration of methotrexate for lymphoma. Resolution of the ophthalmoplegia and the decrease in abnormally high levels of cerebrospinal fluid myelin basic protein after discontinuation of intrathecal medication suggested demyelination from chemotherapy and irradiation.

  9. Physiologic consequences of local heart irradiation in rats

    SciTech Connect

    Geist, B.J.; Lauk, S.; Bornhausen, M.; Trott, K.R. (Institut fuer Strahlenbiologie, GSF, Neuherberg (Germany, F.R.))

    1990-05-01

    Noninvasive methods have been used to study the long-term cardiovascular and pulmonary functional changes at rest and after exercise in adult rats following local heart irradiation with single x-ray doses of 15, 17.5 or 20 Gy, and in non-irradiated control animals. Rats that had undergone a chronic exercise program were compared with untrained cohorts. The earliest dysfunction detected was an increased respiratory rate (f) at 10 weeks after irradiation in the highest dose group. In contrast, both telemetric heart-rate (HR) and rhythm and indirect systolic blood pressure measurements performed at rest only revealed changes starting at 43 weeks after irradiation with 20 Gy, up to which point the rats showed no clinical signs of heart failure. However, the number of minutes required for the recovery of the HR to pre-exercise levels following the implementation of a standardized exercise challenge was elevated in untrained rats compared with their trained cohorts at 18 weeks after irradiation with 20 Gy. Increases in recovery times were required in the two lowest dose groups, starting at 26 weeks after irradiation. It was concluded that the reserve capacity of the cardiopulmonary system masks functional decrements at rest for many months following local heart irradiation, necessitating the use of techniques which reveal reductions in reserve capacities. Further, the influence of local irradiation to the heart and lungs deserves closer scrutiny due to mutual interactions.

  10. Reactivity-flooding effect of the MNSR inner irradiation sites

    Microsoft Academic Search

    I Khamis; K Khattab

    1999-01-01

    For the purpose of safety assessments, evaluation of the reactivity effects of inner irradiation sites, being flooded with water in the MNSR reactor was conducted both numerically and experimentally. Measured and calculated effect of different combination of inner irradiation sites being flooded with water was evaluated numerically and experimentally. Good agreement between measurement and calculated results were obtained.

  11. The pros and cons of using irradiation for phytosanitary treatments

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Irradiation is increasingly being used as a phytosanitary treatment in Asia, Australia and the Americas, but the process is not being used or promoted in the European Union. However, under the current regulatory framework it is possible for food commodities irradiated to prevent the spread of alien...

  12. Some Radiation Techniques Used in the GU-3 Gamma Irradiator

    NASA Astrophysics Data System (ADS)

    Dodbiba, Andon; Ylli, Ariana; Stamo, Iliriana; Kongjika, Efigjeni

    2007-04-01

    Different radiation techniques, measurement of dose and its distibution throughout the irradiated materials are the main problems treated in this paper. The oscillometry method combined with the ionization chamber, as an absolute dosimeter, is used for calibration of routine ECB dosimeters. The dose uniformity, for the used radiation techniques in our GU-3 Gamma Irradiator with Cs-137, is from 93% up to 99%.

  13. Irradiation effects in high-density polyethylene Jussi Polvia

    E-print Network

    Nordlund, Kai

    Irradiation effects in high-density polyethylene Jussi Polvia , Kai Nordlunda a simulations, we have studied the irradiation effects in high density polyethylene. We determined the threshold energy for creating defects in the polyethylene lattice as a function of the incident angle. We found

  14. Retention of Hydrogen Isotopes in Neutron Irradiated Tungsten

    SciTech Connect

    Yuji Hatano; Masashi Shimada; Yasuhisa Oya; Guoping Cao; Makoto Kobayashi; Masanori Hara; Brad J. Merrill; Kenji Okuno; Mikhail A. Sokolov; Yutai Katoh

    2013-03-01

    To investigate the effects of neutron irradiation on hydrogen isotope retention in tungsten, disk-type specimens of pure tungsten were irradiated in the High Flux Isotope Reactor in Oak Ridge National Laboratory followed by exposure to high flux deuterium (D) plasma in Idaho National Laboratory. The results obtained for low dose n-irradiated specimens (0.025 dpa for tungsten) are reviewed in this paper. Irradiation at coolant temperature of the reactor (around 50 degrees C) resulted in the formation of strong trapping sites for D atoms. The concentrations of D in n-irradiated specimens were ranging from 0.1 to 0.4 mol% after exposure to D plasma at 200 and 500 degrees C and significantly higher than those in non-irradiated specimens because of D-trapping by radiation defects. Deep penetration of D up to a depth of 50-100 µm was observed at 500 degrees C. Release of D in subsequent thermal desorption measurements continued up to 900 degrees C. These results were compared with the behaviour of D in ion-irradiated tungsten, and distinctive features of n-irradiation were discussed.

  15. Blood lipid fractions of rats after cumulative gamma irradiation

    NASA Astrophysics Data System (ADS)

    El-Salam, Soad Abd; Yousri, R. M.; Sallam, T.

    1994-07-01

    Triglycerides, cholesterol, total lipids and phospholipids levels were investigated in the serum of rats after cumulative whole body ? irradiation at doses from 2.5 to 10 Gy.Hyperlipidemia was observed after irradiation doses of 7.5 and 10 Gy. Different mechanisms were postulated for the radiation induced changes in the levels of serum lipid.

  16. The pros and cons of using irradiation for phytosanitary treatments

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Irradiation is increasingly being used as a phytosanitary treatment in Asia, Australia and the Americas, but the process is not being used or promoted in the European Union. However, under the current regulatory framework it is possible for food commodities irradiated to prevent the spread of alien ...

  17. Irradiation Effects in Strain-aged Pressure Vessel Steel

    Microsoft Academic Search

    M. Grounes; H. P. Myers

    1962-01-01

    BOTH neutron irradiation and normal ageing phenomena may separately cause deterioration in the properties of mild steels by increasing the brittle-ductile transition temperature. In the case of reactor pressure vessels, the effects of neutron irradiation alone may increase this transition temperature to values well above room temperature. For purposes of reactor design, as well as for estimating the permissible service-life

  18. Kuiper objects: simulation of space weathering by ion irradiation

    Microsoft Academic Search

    J. Paillet; R. Brunetto; M. A. Barucci; E. Dotto; G. Strazulla

    2003-01-01

    Waiting for direct investigation of Kuiper Belt Objects surfaces, laboratory experiments are essential to understand mechanisms of space weathering. We present results of laboratory experiments on methane irradiation performed at Catania Observatory. Frozen methane at 16 K was irradiated by hundreds of keV Ar++ ions. Reflectance spectra from 0.65 \\\\micron to 2.7 \\\\micron have been taken ``in situ\\

  19. Backscattering measuring system for optimization of intravenous laser irradiation dose

    NASA Astrophysics Data System (ADS)

    Rusina, Tatyana V.; Popov, V. D.; Melnik, Ivan S.; Dets, Sergiy M.

    1996-11-01

    Intravenous laser blood irradiation as an effective method of biostimulation and physiotherapy becomes a more popular procedure. Optimal irradiation conditions for each patient are needed to be established individually. A fiber optics feedback system combined with conventional intravenous laser irradiation system was developed to control of irradiation process. The system consists of He-Ne laser, fiber optics probe and signal analyzer. Intravenous blood irradiation was performed in 7 healthy volunteers and 19 patients with different diseases. Measurements in vivo were related to in vitro blood irradiation which was performed in the same conditions with force-circulated venous blood. Comparison of temporal variations of backscattered light during all irradiation procedures has shown a strong discrepancy on optical properties of blood in patients with various health disorders since second procedure. The best cure effect was achieved when intensity of backscattered light was constant during at least five minutes. As a result, the optical irradiation does was considered to be equal 20 minutes' exposure of 3 mW He-Ne laser light at the end of fourth procedure.

  20. Potential chemical markers for the identification of irradiated sausages.

    PubMed

    Kwon, Joong Ho; Akram, Kashif; Nam, Ki Chang; Min, Byungrok; Lee, Eun Joo; Ahn, Dong U

    2012-09-01

    Hydrocarbons, gas compounds, and off-odor volatiles were determined for irradiated (0 or 5 kGy) commercial sausages with different fat contents (16% and 29%) during a 60-d storage period at 4 °C. Total of 4 hydrocarbons (C14:1, C15:0, C16:2, and C17:1) were detected only in irradiated sausages: the amount of C16:2 was the highest, followed by C17:1, C14:1, and C15:0. The concentrations of hydrocarbons decreased significantly (P < 0.05) with storage, but were still detectable at the end of 60-d storage. Irradiated sausages produced significantly higher amounts of CO than the nonirradiated ones. CH(4) was detected only in irradiated sausages. Dimethyl disulfide was detected only in irradiated sausages and its concentration decreased significantly (P < 0.05) with storage. Fat content of sausages showed a significant effect on the production and retention of hydrocarbons, gas compounds, and sulfur volatiles in irradiated sausages during storage. Some hydrocarbons (C16:2, C17:1, C14:1, and C15:0), CH(4) , and dimethyl disulfide were only found in irradiated sausages indicating that these compounds can be used as potential markers for irradiated sausages. PMID:22897432

  1. THE EFFECT OF CHRONIC GAMMA IRRADIATION ON MOUSE OVARIES

    Microsoft Academic Search

    Kopylova

    1958-01-01

    strain 57 (black), a quantitative decrease of all groups of follicles, ; in the body cavity. This is particularly apparent in the group of mice ; irradiated with the largest daily dosc of 0.4 r. Despite vast tissue injury ; individual ovaries contained a small number of cavity developing and primordial ; follicles of normal structure. Chronic irradiation did not

  2. Aging-like changes in the transcriptome of irradiated microglia.

    PubMed

    Li, Matthew D; Burns, Terry C; Kumar, Sunny; Morgan, Alexander A; Sloan, Steven A; Palmer, Theo D

    2015-05-01

    Whole brain irradiation remains important in the management of brain tumors. Although necessary for improving survival outcomes, cranial irradiation also results in cognitive decline in long-term survivors. A chronic inflammatory state characterized by microglial activation has been implicated in radiation-induced brain injury. We here provide the first comprehensive transcriptional profile of irradiated microglia. Fluorescence-activated cell sorting was used to isolate CD11b+ microglia from the hippocampi of C57BL/6 and Balb/c mice 1 month after 10 Gy cranial irradiation. Affymetrix gene expression profiles were evaluated using linear modeling and rank product analyses. One month after irradiation, a conserved irradiation signature across strains was identified, comprising 448 and 85 differentially up- and downregulated genes, respectively. Gene set enrichment analysis demonstrated enrichment for inflammation, including M1 macrophage-associated genes, but also an unexpected enrichment for extracellular matrix and blood coagulation-related gene sets, in contrast previously described microglial states. Weighted gene coexpression network analysis confirmed these findings and further revealed alterations in mitochondrial function. The RNA-seq transcriptome of microglia 24-h postradiation proved similar to the 1-month transcriptome, but additionally featured alterations in apoptotic and lysosomal gene expression. Reanalysis of published aging mouse microglia transcriptome data demonstrated striking similarity to the 1-month irradiated microglia transcriptome, suggesting that shared mechanisms may underlie aging and chronic irradiation-induced cognitive decline. GLIA 2015;63:754-767. PMID:25690519

  3. Commercialization of irradiation on fresh fruits and vegetables

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This book chapter describes current applications of irradiation on fresh fruits and vegetables. Major applications of irradiation around the world include disinfestation of fresh fruits to eliminate pests and reduction of tuber crop losses by inhibiting sprouting. In recent years, a number of irrad...

  4. Physica B 308310 (2001) 612615 Irradiation effects in semiconducting diamonds

    E-print Network

    Chen, Reuven

    2001-01-01

    Physica B 308­310 (2001) 612­615 Irradiation effects in semiconducting diamonds N. Kristianpoller irradiation on semiconducting diamonds (type IIb) were studied and compared with those induced at the same conditions in natural (type Ia) and in synthetic diamonds. Methods of optical absorption, of X-ray and light

  5. EFFECT OF ION BEAM IRRADIATION ON HARDNESS OF POLYETHYLENE TEREPHTHALATE

    Microsoft Academic Search

    N. L. Singh; C. F. Desai; N. Shah; P. H. Soni; V. Shrinet; D. K. Avasthi

    2002-01-01

    Ion beam irradiation as one of the effective methods of polymer modification has been used on the PET films. The ion beam used was Li(50 MeV) of various fluences. The Vickers' hardness of the films irradiated at different ion fluences was measured. The hardness tests on each film were carried out at different loads. The true bulk hardness of the film

  6. A small size continuous run industrial gamma irradiator

    Microsoft Academic Search

    Wilson A. P. Calvo; Paulo R. Rela; Francisco E. Springer; Fábio E. Da Costa; Nelson M. Omi; Leonardo G. A. E. Silva

    2004-01-01

    A new small size gamma irradiator is being set up at Instituto de Pesquisas Energeticas e Nucleares (IPEN-CNEN\\/SP), Brazil, with a revolutionary design. The developed technology for this facility consists of continuous tote box transport system, comprising a single concrete vault, where the automated transport system of products inside and outside of the irradiator utilizes a rotating door, integrated with

  7. Irradiation and heating effects in amethyst crystals from brazil

    Microsoft Academic Search

    Clemencio Teodoro Dotto; Sadao Isotani

    1991-01-01

    In this work we report optical absorption spectroscopy study of thermal and irradiation effects on samples of amethyst from Minas Gerais and Rio Grande do Sul, Brazil. Three bands were studied: 10500 cm?1 (k), 18300 cm?1 (?) and 28000 cm?1 (?). Thermal and irradiation effects shows that the ? and ? bands belongs to a same center and the k

  8. Reconstruction of solar irradiance since 1610: Implications for climate change

    Microsoft Academic Search

    Judith Lean; Juerg Beer; Raymond Bradley

    1995-01-01

    Solar total and ultraviolet (UV) irradiances are reconstructed annually from 1610 to the present. This epoch includes the Maunder Minimum of anomalously low solar activity (circa 1645-1715) and the subsequent increase to the high levels of the present Modern Maximum. In this reconstruction, the Schwabe (11-year) irradiance cycle and a longer term variability component are determined separately, based on contemporary

  9. Food irradiation: The past fifty years as prologue to tomorrow

    Microsoft Academic Search

    Urbain

    1989-01-01

    Food Irradiation is a process ready for use. Backing that statement are more than four decades of research and development that have provided the extensive knowledge necessary to proceed confidently with its utilization. Research done since 1943 has demonstrated that treating foods with irradiation can provide considerable advantages: preserves foods; decontaminates food; controls maturation; alters chemical composition for quality improvement;

  10. Raman Microscopic Characterization of Proton-Irradiated Polycrystalline Diamond Films

    NASA Technical Reports Server (NTRS)

    Newton, R. L.; Davidson, J. L.; Lance, M. J.

    2004-01-01

    The microstructural effects of irradiating polycrystalline diamond films with proton dosages ranging from 10(exp 15) to 10(exp 17) H(+) per square centimeter was examined. Scanning Electron Microscopy and Raman microscopy were used to examine the changes in the diamond crystalline lattice as a function of depth. Results indicate that the diamond lattice is retained, even at maximum irradiation levels.

  11. Materials for cold neutron sources: Cryogenic and irradiation effects

    Microsoft Academic Search

    1990-01-01

    Materials for the construction of cold neutron sources must satisfy a range of demands. The cryogenic temperature and irradiation create a severe environment. Candidate materials are identified and existing cold sources are briefly surveyed to determine which materials may be used. Aluminum- and magnesium-based alloys are the preferred materials. Existing data for the effects of cryogenic temperature and near-ambient irradiation

  12. Bystander Effects Induced by Medium From Irradiated Cells: Similar Transcriptome Responses in Irradiated and Bystander K562 Cells

    SciTech Connect

    Herok, Robert; Konopacka, Maria [Department of Experimental and Clinical Radiobiology, Maria Sklodowska-Curie Memorial Cancer Center and Institute of Oncology, Gliwice (Poland); Polanska, Joanna; Swierniak, Andrzej [System Engineering Group, Institute of Automatic Control, Silesian University of Technology, Gliwice (Poland); Rogolinski, Jacek [Department of Experimental and Clinical Radiobiology, Maria Sklodowska-Curie Memorial Cancer Center and Institute of Oncology, Gliwice (Poland); Jaksik, Roman [System Engineering Group, Institute of Automatic Control, Silesian University of Technology, Gliwice (Poland); Hancock, Ronald [Laval University Cancer Research Centre, Hotel-Dieu Hospital, Quebec, QC (Canada); Rzeszowska-Wolny, Joanna, E-mail: jwolny@io.gliwice.p [Department of Experimental and Clinical Radiobiology, Maria Sklodowska-Curie Memorial Cancer Center and Institute of Oncology, Gliwice (Poland); System Engineering Group, Institute of Automatic Control, Silesian University of Technology, Gliwice (Poland)

    2010-05-01

    Purpose: Cells exposed to ionizing radiation release factors that induce deoxyribonucleic acid damage, chromosomal instability, apoptosis, and changes in the proliferation rate of neighboring unexposed cells, phenomena known as bystander effects. This work analyzes and compares changes in global transcript levels induced by direct irradiation and by bystander effects in K562 (human erythroleukemia) cells. Methods and Materials: Cells were X-irradiated with 4 Gy or transferred into culture medium collected from cells 1 h after irradiation (irradiation-conditioned medium). Global transcript profiles were assessed after 36 h of growth by use of Affymetrix microarrays (Affymetrix, Santa Clara, CA) and the kinetics of change of selected transcripts by quantitative reverse transcriptase-polymerase chain reaction. Results: The level of the majority (72%) of transcripts changed similarly (increase, decrease, or no change) in cells grown in irradiation-conditioned medium or irradiated, whereas only 0.6% showed an opposite response. Transcript level changes in bystander and irradiated cells were significantly different from those in untreated cells grown for the same amount of time and were confirmed by quantitative reverse transcriptase-polymerase chain reaction for selected genes. Signaling pathways in which the highest number of transcripts changed in both conditions were found in the following groups: neuroactive ligand-receptor, cytokine-cytokine receptor interaction, Janus Kinase-Signal Transducers and Activators of Transcription (JAK-STAT) and Mitogen-Activated Protein Kinase (MAPK) In control cells more transcripts were downregulated than in irradiated and bystander cells with transcription factors YBX1 and STAT5B, heat shock protein HSPA1A, and ribonucleic acid helicase DDX3X as examples. Conclusions: The transcriptomes of cells grown in medium from X-irradiated cells or directly irradiated show very similar changes. Signals released by irradiated cells may cause changes in the transcriptome of neighboring cells that sustain their survival.

  13. Kinetic analysis of the thermal decomposition of gamma-irradiated nickel oxalate

    Microsoft Academic Search

    R. M. Mahfouz; M. M. M. Abd-El-Wahab

    1994-01-01

    The isothermal decomposition of un-irradiated and pre-gamma-irradiated dehydrated nickel oxalate has been studied in the temperature range 250-365°C. Irradiation appears to increase the number of potential nuclei-forming sites without modification of the mechanism both for un-irradiated and has been shown to proceed by a nucleation and growth mechanism both for un-irradiated and pre-gamma-irradiated samples of nickel oxalate. Application of Vand-Primak

  14. Effects of electron-beam irradiation on conducting polypyrrole nanowires

    SciTech Connect

    Hong, Young Ki; Park, Dong Hyuk; Park, Se Hee; Park, Soung Kyu; Joo, Jinsoo [Department of Physics and Hybrid Nanostructure Research Laboratory, Korea University, Seoul 136-713 (Korea, Republic of)

    2009-02-02

    Conducting polypyrrole (PPy) nanowires (NWs) were irradiated by a relatively high energy (300 keV-2 MeV) electron-beam (e-beam) generated from a linear electron accelerator in an atmospheric environment. From the current-voltage characteristics of pristine and 2 MeV e-beam irradiated PPy NWs, we observed a dramatic variation in resistance from 8.0x10{sup 2} to 1.45x10{sup 8} {omega}, that is, we observed a transition from conducting states to nonconducting states through the e-beam irradiation. To discern conformational changes and the doping states of PPy NWs through the e-beam irradiation, we measured Raman and ultraviolet-visible absorption spectra for the PPy NWs. As the energy of the e-beam irradiation increased, we observed that the PPy NWs were changed from doping states to dedoping states with conformational modification including the variation in {pi}-conjugation length.

  15. Defects and microstructural evolution of proton irradiated titanium carbide

    NASA Astrophysics Data System (ADS)

    Dickerson, Clayton; Yang, Yong; Allen, Todd R.

    2012-05-01

    Titanium carbide has been identified as a candidate material for advanced coated nuclear fuel components, however little is known about the response of TiC to particle irradiation at elevated temperatures. To understand the radiation effects in TiC, proton irradiations were conducted to three doses (0.17, 0.34, and 0.80 dpa) at three temperatures (600 °C, 800 °C, and 900 °C), and post irradiation examination was performed with a number of TEM techniques to evaluate the irradiated microstructures. The predominant irradiation induced aggregate defects found by high resolution TEM and diffraction contrast TEM were interstitial Frank-type loops, while unfaulted loops were also identified. By monitoring the loop sizes and densities and accounting for the interstitials which formed the loops, a marked increase in vacancy point defect mobility was observed around 800 °C.

  16. Effect of green laser irradiation on hydrogen production

    NASA Astrophysics Data System (ADS)

    Bidin, Noriah; Razak, Siti Noraiza A.; Radiana Azni, Siti; Nguroho, Waskito; Mohsin, Ali Kamel; Abdullah, Mundzir; Krishnan, Ganesan; Bakhtiar, Hazri

    2014-06-01

    The effect of green laser irradiation on hydrogen production via water electrolysis was investigated. Diode pumped solid-state laser operating in second harmonic generation was employed as a source of irradiation. The hydrogen production system was also irradiated by a conventional light, a halogen source, for comparison. The best catalyst was identified by mixing distilled water with two types of salt: NaCl and Na2SO4. Optimization of hydrogen production from water electrolysis was realized by using NaCl and green laser irradiation. The power of green laser irradiation and the concentration of NaCl in water contribute to hydrogen production. The hydrogen yield also depends on the distance and direction of the green beam to the electrode.

  17. Reconstructing the Solar VUV Irradiance Over the Past 60 Years

    NASA Technical Reports Server (NTRS)

    Chamberlin, Phillip C.

    2011-01-01

    Actual observations of the solar spectral irradiance are extremely limited on climate time scales; therefore, various empirical models use solar proxies to reconstruct the actual output of the Sun over long time scales. The Flare Irradiance Spectral Model (FISM) is an empirical model of the solar irradiance spectrum from 0.1 to 190 nm at 1 nm spectral resolution and on a I-minute time cadence. The goal of FISM is to provide accurate solar spectral irradiances over the vacuum ultraviolet (VUV: 0-200 nm) range as input for ionospheric and thermospheric. A brief overview of the proxies used in the FISM model will be given, and also discussed is how the Solar Dynamics Observatory (SDO) EUV Variability Experiment (EVE) will contribute to improving FISM estimates and its accuracies. Also presented will be a discussion of other solar irradiance proxies and measurements, and their associated uncertainties, used for solar spectral reconstructions.

  18. A reconstruction of solar irradiance using a flux transport model

    NASA Astrophysics Data System (ADS)

    Dasi Espuig, Maria; Krivova, Natalie; Solanki, Sami K.; Jiang, Jie

    2012-07-01

    Solar irradiance is one of the important drivers of the Earth's global climate, but it has only been measured for the past 33 years. Its reconstructions are therefore crucial to study longer term variations relevant to climate timescales. Most successful in reproducing the measured irradiance variations have being the models that are based on the assumption that irradiance changes are caused by the evolution of the photospheric magnetic field. Our SATIRE-S model is one of these, which uses solar full-disc magnetograms as an input, and these are available for less than four decades. To reconstruct the irradiance back to times when no observed magnetograms are available, we combine the SATIRE-S model with synthetic magnetograms, produced using a surface flux transport model. The model is fed with daily, observed or modelled statistically, records of sunspot positions, areas, and tilt angles. The concept of overlapping ephemeral region cycles is used to describe the secular change in the irradiance.

  19. Modelling total solar irradiance using a flux transport model

    NASA Astrophysics Data System (ADS)

    Dasi Espuig, Maria; Jiang, Jie; Krivova, Natalie; Solanki, Sami

    2014-05-01

    Reconstructions of solar irradiance into the past are of considerable interest for studies of solar influence on climate. Models based on the assumption that irradiance changes are caused by the evolution of the photospheric magnetic field have been the most successful in reproducing the measured irradiance variations. Our SATIRE-S model is one of these. It uses solar full-disc magnetograms as an input, and these are available for less than four decades. Thus, to reconstruct the irradiance back to times when no observed magnetograms are available, we combine the SATIRE-S model with synthetic magnetograms, produced using a surface flux transport model. The model is fed with daily, observed or modelled statistically, records of sunspot positions, areas, and tilt angles. To describe the secular change in the irradiance, we used the concept of overlapping ephemeral region cycles. With this technique TSI can be reconstructed back to 1700.

  20. A reconstruction of solar irradiance using a flux transport model

    NASA Astrophysics Data System (ADS)

    Dasi Espuig, Maria; Jiang, Jie; Krivova, Natalie; Solanki, Sami

    2013-04-01

    Reconstructions of solar irradiance into the past are of considerable interest for studies of solar influence on climate. Models based on the assumption that irradiance changes are caused by the evolution of the photospheric magnetic field have been the most successful in reproducing the measured irradiance variations. Our SATIRE-S model is one of these. It uses solar full-disc magnetograms as an input, and these are available for less than four decades. Thus, to reconstruct the irradiance back to times when no observed magnetograms are available, we combine the SATIRE-S model with synthetic magnetograms, produced using a surface flux transport model. The model is fed with daily, observed or modelled statistically, records of sunspot positions, areas, and tilt angles. To describe the secular change in the irradiance, we used the concept of overlapping ephemeral region cycles. With this technique TSI can be reconstructed back to 1610.