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1

Martyne Perrot Le monde sous globe  

E-print Network

« enfance du monde » : celle que construisirent, en le parcourant, des voyageurs illustres comme Marco Polo s'invente à chaque pas. Si Marco Polo réunit ses récits de voyage sous le titre Le Livre des mer

Paris-Sud XI, Université de

2

Nappes et sous-varietes. 2.1 Nappes.  

E-print Network

Chapitre 2 Nappes et sous-vari´et´es. 2.1 Nappes. Apr`es les courbes on voudrait ´etudier les`eres. La matrice A d´efinie par A = fi xj (x) 1id 1jd 17 #12;18 CHAPITRE 2. NAPPES ET SOUS-VARI´ET´ES. est

Mounoud, Pierre

3

Topologie et combinatoire des sous-varietes legendriennes  

E-print Network

Topologie et combinatoire des sous-vari´et´es legendriennes Emmanuel FERRAND Institut Math mati`eres Chapitre 1. Introduction : La topologie tautologique n'est pas une tautologie topologique 7,version1-27Feb2009 #12;tel-00364936,version1-27Feb2009 #12;CHAPITRE 1 Introduction : La topologie

Paris-Sud XI, Université de

4

Hypertriglyc?rid?mie majeure sous tamoxif?ne  

PubMed Central

Plusieurs agents pharmacologiques sont incrimins dans les hyperlipidmies. Le tamoxifne fournit un exemple de mdicament hypertriglycridmiant. Nous dcrivons ici le cas ?une patiente atteinte de cancer du sein traite par tamoxifne qui a prsent une hypertriglycridmie svre. Nous prsentons aussi une brve revue de la littrature et discutons les mcanismes sous jacents aux effets hypertriglycridmiants du tamoxifne. PMID:23396984

Khabbal, Youssef; El Ouahabi, Hanane; Bensbaa, Salma; Agerd, Loubna; Brahmi, Sami; El Mesbahi, Omar; Ajdi, Farida

2012-01-01

5

Comportement d'une couche laboure sous des actions de compactage en fonction de son tat  

E-print Network

manifestation was accompanied by an increase of matter flow. The effect of the initial structural state évolution lente et progressive sous l'action du climat, et généralement brutale sous l'action des opérations

Paris-Sud XI, Université de

6

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

E-print Network

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

Michelet, Sophie

2006-01-01

7

Xen V3 sous Scientific Linux V4 Retour d'exprience sur la mise en place d'un  

E-print Network

Xen V3 sous Scientific Linux V4 Retour d'expérience sur la mise en place d'un serveur Xen sous Scientific Linux V4 Dominique CARON Ing´enieur de Recherche CNRS Administrateur Syst`eme UNIX, Universit´e MONTPELLIER II Powered By 'Prosper/ ¢¡ £¤ ¥ ' Xen V3 sous Scientific Linux V4 ­ p.1/13 #12;But de la manip

van Tiggelen, Bart

8

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

E-print Network

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

Paris-Sud XI, Université de

9

Approches exprimentale et thorique du comportement thermomcanique sous chargement multiaxial d'alliages mmoire de forme polycristallins  

Microsoft Academic Search

Depuis une dizaine d'annes, des alliages mmoire de forme (AMF) sont sollicits, en chargement multiaxial, dans le domaine de la pseudolasticit (transformation martensitique ``renversable'' induite sous contrainte) et de la pseudoplasticit (rorientation des plaquettes de martensite sous l'effet des contraintes externes). Les rsultats exprimentaux obtenus montrent que le choix du chemin de chargement multiaxial influe fortement sur la rponse

C. Bouvet; S. Calloch; C. Lexcellent

2002-01-01

10

Actes JFPC 2007 Filtrage pour l'isomorphisme de sous-graphe  

E-print Network

Par Contraintes (PPC), qui fournit un cadre g´en´erique pour la r´esolution de n'importe quel probl´ement formul´e sous la forme de contraintes [15, 16]. Afin de rendre la PPC comp´e- titive avec les approches d´en´eral d'isomorphisme de sous-graphe approxim´e, et a montr´e que la PPC est comp´etitive avec les ap

Deville, Yves

11

DISLOCATIONS PARTIELLES DANS UN CARBURE DE TANTALE SOUS-ST0152CHIOMTRIQUE  

E-print Network

911. DISLOCATIONS PARTIELLES DANS UN CARBURE DE TANTALE SOUS-ST0152CHIOM?TRIQUE Par J. L. MARTIN précédent a révélé l'existence de défauts d'empilement intrinsèques dans un carbure sous-st0153chiométrique carbure a montré que les défauts d'empilement étaient limités par des dislocations de Shockley. Les

Paris-Sud XI, Université de

12

Comment rduire la sous-valuation lors de l'introduction en bourse?  

Microsoft Academic Search

(VF)La valorisation des entreprises introduites en bourse s'opre dans un contexte d'incertitude et d'asymtrie d'information. Il en rsulte frquemment une sous-valuation l'introduction:les metteurs diffusent les actions dans le public un prix plus faible que le \\

Graldine Broye; Alain Schatt

2002-01-01

13

Introduction la base PHILIDOR MERCURE AIRS Sous la direction d'Anne Pijus  

E-print Network

Introduction à la base PHILIDOR « MERCURE AIRS » Sous la direction d'Anne Piéjus Ce corpus « Mercure Airs », accueilli dans la base oeuvres, constitue le premier volet d'une double publication : s'y ajoutera une base « Mercure », quantitativement beaucoup plus importante, qui traitera l

Paris-Sud XI, Université de

14

Prfecture de Police. --Avis de vacance du poste de sous-directeur du Laboratoire Central de la Prfec-  

E-print Network

Pr�fecture de Police. -- Avis de vacance du poste de sous-directeur du Laboratoire Central de la Pr�fec- ture de Police (L.C.P.P.). Le poste de sous-directeur du Laboratoire Central de la Pr�- fecture de Police (L.C.P.P.) sera vacant � compter du 30 octobre 2014. La Pr�fecture de Police organise donc un

van Tiggelen, Bart

15

Sous-Evaluation Des Introductions En Bourse: Application D?une Frontiere Stochastique Sur Le Nouveau Marche  

Microsoft Academic Search

cet article, nous cherchons estimer le degr de sous-valuation des titres introduits sur le Nouveau March de la Bourse de Paris partir d'une frontire stochastique. La mesure du degr de sous-valuation des titres introduits repose sur l'estimation d'une frontire de prix stochastique qui suppose une erreur asymtrique distribue, respectivement, selon la loi normale tronque et la loi exponentielle.

Samy Ben Naceur; Mohamed Goaied

2003-01-01

16

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

E-print Network

-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

Sablik, Mathieu

17

Quality changes during storage of sous vide cooked green beans (Phaseolus vulgaris)  

Microsoft Academic Search

The acceptability and quality of sous vide cooked green beans (Phaseolus vulgaris) were investigated during chilled storage. A suitable heating procedure was established whereby 2.0-kg packages were heat\\u000a processed at 90C for 25 min, corresponding to an average pasteurization value, PV70,10, of 14 min. During storage for up to 25 days at 3C drip loss, pH, colour (Minolta L\\u000a \\u000a *

Susanne Knchel; Randi Vangsgaard; Lone Sholm Johansen

1997-01-01

18

Soutien Des Cours Et Sous-Evaluation Des Introductions Sur Le Nouveau Marche  

Microsoft Academic Search

Cet article a t consacr l'tude du degr de sous-valuation de 135 entreprises introduites sur le Nouveau March de la Bourse de Paris. Une analyse statistique prliminaire, travers les coefficients d'aplatissement et d?asymtrie, indique la prsence d'une politique de soutien des cours par les intermdiaires qui s'affaiblit progressivement partir de la premire semaine. Pour affiner l'analyse, nous

Samy Ben Naceur; Samir Ghazouani

2003-01-01

19

Chapitre paru in Myriam Chimnes (dir.), La vie musicale sous Vichy, Paris, Complexe, 2000.  

E-print Network

« captation » des audiences : elle occupe près des deux tiers des programmes de Radio-Paris, avec une très. C?CILE M?ADEL1 Pauses musicales ou les éclatants silences de Radio-Paris Résumé : Face à une radiodiffusion vichyste immergée dans les ambiguïtés équivoques du Pétainisme, Radio-Paris, placée sous l

Paris-Sud XI, Université de

20

European HDR research programme at Soultz-sous-Forts (France) 19871996  

Microsoft Academic Search

The site at Soultz-sous-Forts (France) has been selected as the future European HDR research site (Garnish, J., Baria, R., Baumgrtner, J., Grard, A., 1994. GRC Trans. 18, 431438; 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

Roy Baria; Jrg Baumgrtner; Andr Grard; Reinhard Jung; John Garnish

1999-01-01

21

SPECTRES LECTRONIQUES DE L'OXYDE AZOTEUX ET DE L'OXYDE AZOTIQUE SOUS DIFFRENTS TATS  

E-print Network

423. SPECTRES ?LECTRONIQUES DE L'OXYDE AZOTEUX ET DE L'OXYDE AZOTIQUE SOUS DIFF?RENTS ?TATS Par Mme (France). Les spectres d'absorption de l'oxyde azoteux et de l'oxyde azotique a 1'6tat vapeur dans l analogue faite a 1'6tat condense. On doit s'attendre a des resultats int6ressants dans le cas de l'oxyde

Boyer, Edmond

22

Absorption du rayonnement 12 et 8 millimtres par les vapeurs de propane sous pression  

E-print Network

Absorption du rayonnement 12 et 8 millimètres par les vapeurs de propane sous pression A. Battaglia des pertes diélectriques (03B5") présentées par le propane gazeux aux fréquences de 24 et 36 GHz, à la Birnbaum. Abstract. 2014 Experimental study of dielectric losses (03B5") presented by gaseous propane

Boyer, Edmond

23

SUR LES ORBITES D'UN SOUS-GROUPE SPHRIQUE DANS LA VARIT DES DRAPEAUX  

E-print Network

'adhérenced'une orbite de G dans Y . Soit V l'adhérence dans Y d'une orbite de B dans G/H. Dans [Bri01, après la of G/H and O be the closure of a G-orbit in Y . Let V be the closure in Y of a B-orbit in G/H. In [Bri Borel de G. Soit H un sous-groupe fermé de G. On suppose que H est sphérique c'est-à-dire (voir [Bri86

Ressayre, Nicolas

24

C^ones limites des sous-groupes discrets des groupes reductifs  

E-print Network

´esum´e Soient K un corps local, G un K-groupe r´eductif et G = G(K). Si est un sous-groupe de G, Y. Benoist a d. Benoist a associ´e `a son c^one limite l : c'est le c^one ferm´e engendr´e par () dans E+ . Il est stable naturellement muni d'une forme ration- nelle et l est `a support rationnel. R´eciproquement, Y. Benoist

Quint, Jean-François

25

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

Microsoft Academic Search

An exhaustive analysis of 3000 macroscopic fractures encountered in the geothermal Hot Dry Rock borehole, EPS-1, located inside the Rhine graben (Soultz-sous-Forts, 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

Albert Genter; Herv Traineau

1996-01-01

26

Sous-modules d'unit'es en th'eorie d'Iwasawa Jean-Robert Belliard  

E-print Network

sa torsion du module des unit'es circulaires de Sinnott ([Si], la d'efinition e* *st rappel'ee en 2 Sous-modules d'unit'es en th'eorie d'Iwasawa Jean partir des unit'es circulaires `a la Sinnott soit libre. On d'etaille ensuite des exemples qu* *i

Belliard, Jean-Robert

27

Sous-vide cooking of traditional meat products: effect on the microbiology of dry-cured pork foreleg  

Microsoft Academic Search

The aim of this work was to assess the effect of sous-vide cooking and storage at different temperatures in the microbiology of a traditional meat product (dry-cured pork foreleg, Lacn gallego) that is usually consumed after it is desalted and boiled. Microbial parameters (total plate counts, Micrococcaceae, Staphylococcus aureus, lactic acid bacteria, Enterobacteriaceae, Clostridia hydrogen sulphide producers and the presence

A. Cobos; O. Diaz

2007-01-01

28

Approches exprimentale et thorique du comportement thermomcanique sous chargement multiaxial d'alliages mmoire de forme polycristallins  

NASA Astrophysics Data System (ADS)

Depuis une dizaine d'annes, des alliages mmoire de forme (AMF) sont sollicits, en chargement multiaxial, dans le domaine de la pseudolasticit (transformation martensitique renversable induite sous contrainte) et de la pseudoplasticit (rorientation des plaquettes de martensite sous l'effet des contraintes externes). Les rsultats exprimentaux obtenus montrent que le choix du chemin de chargement multiaxial influe fortement sur la rponse mcanique de I'AMF. Actuellement, malgr les nombreux modles proposs dans la littrature, la simulation des chargements nonproportionnels n'est pas tout fait opratoire. C'est la raison pour laquelle un modle de comportement des AMF sous chargements proportionnels et nonproportionnels est propos dans ce papier. A cet effet, deux surfaces de transformation directe et inverse, une dformation et une contrainte quivalentes sont introduites dans le cadre de la thermodynamique des processus irrversibles. Pour un Cu-Al-Be polycristallin, la capacit de prdiction du comportement sous sollicitation complexe est bonne avec un nombre faible de paramtres matriau identifier.

Bouvet, C.; Calloch, S.; Lexcellent, C.

2002-12-01

29

Utilisation d'eau basse temprature pour le forage de cultures sous abris. II. Effets du chauffage du sol sur la  

E-print Network

Utilisation d'eau à basse température pour le forçage de cultures sous abris. II. Effets du, pour le lis, dont l'apex reste très peu de temps sous la surface du sol, l'effet du chauffage du sol water for forcing greenhouse crops. II. Effects of soil warming on growth and development of bulbous

Paris-Sud XI, Université de

30

STRESS STATE AT SOULTZ-SOUS-FORTS TO 5 KM DEPTH FROM WELLBORE FAILURE AND HYDRAULIC OBSERVATIONS  

Microsoft Academic Search

Observations of breakouts and drilling-induced tension fractures (DITFs) in two 5 km deep boreholes of the European Enhanced Geothermal Project of Soultz-sous-Forts, France have been combined with the analysis of pressure data from stimulation tests in all 3 deep wells to obtained a description of the state of stress in the granite down to 5 km depth. The orientation of

Benot Valley; Keith F. Evans

2007-01-01

31

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

E-print Network

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

Paris-Sud XI, Université de

32

Sous-modules d'unit es en th eorie d'Iwasawa Jean-Robert Belliard  

E-print Network

#19;e modulo sa torsion du module des unit#19;es circulaires de Sinnott ([Si], la d#19;e#12;nition estSous-modules d'unit#19;es en th#19;eorie d'Iwasawa Jean-Robert Belliard Universit#19;e de Franche�sante, en termes de \\descente galoisienne", pour que le module d'Iwasawa obtenu #18;a partir des unit#19;es

Belliard, Jean-Robert

33

La chirurgie coronaire sous circulation extra-corporelle chez le patient diab?tique  

PubMed Central

Nous rapportons les rsultats de la chirurgie coronaire chez une population de coronariens diabtiques oprs sous circulation extra-corporelle dans le service de chirurgie cardiaque de l'hpital militaire d'instruction Mohammed V de Rabat. C'est une tude rtrospective mene entre Janvier 2008 et Fvrier 2012 (4 ans), portant sur 103 patients diabtiques conscutifs oprs pour pontage coronaire. Lge moyen des patients tait de 618,7ans (37-82ans) avec un sexe ratio (H/F) de 3,9. Tous les patients diabtiques de type 2 et sous traitement anti-diabtique ont t inclus dans cette tude. La stnose du tronc commun gauche tait prsente chez 26,2% des patients et 53,4% taient tritronculaires. Quatre-vingt patients (78,6%) taient insulino-ncessitant, l'Euro-score moyen tait de 1,631% et le nombre moyen de pontage de 2,30,7. Les dures moyennes de la circulation extra-corporelle et du clampage aortique taient respectivement de 134,4 42 min et 76 28 min. La mortalit hospitalire tait de 2 dcs (1,9%), les dures moyennes de ventilation artificielle, du sjour en ranimation et du sjour postopratoire taient respectivement de 7h (5-16h), 48h (42-52h) et 15,6 8,6 jours. Les complications postopratoires taient l'infarctus du myocarde, l'infection de paroi, la mdiastinite et le bas dbit cardiaque chez respectivement 1,9%, 10,7%, 3,9% et 1,9% des patients. Il ressort de notre tude, que les facteurs prdictifs d'infection post opratoire taient la dure de ventilation artificielle (p = 0,002), la dure de la circulation extra-corporelle (p < 0,001) en plus du tabac (p = 0,004) et de l'obsit (p = 0,005). Les patients ont t contacts par tlphone ou lors de la consultation rgulire de contrle. Le taux de suivi a atteint 92,1% et la survie 2 ans tait de 98,9% des patients contrls avec une mortalit tardive de 1% avec un dcs suite un accident vasculaire crbral tendu. Le contrle a montr un cas de r-hospitalisation pour pousse d'insuffisance cardiaque mais aucun cas de rcidive angineuse, d'infarctus du myocarde ou de besoin de revascularisation. La chirurgie coronaire chez le diabtique offre d'excellents rsultats court et moyen terme au dtriment d'une faible morbi-mortalit ce qui en fait le traitement de choix.

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

2014-01-01

34

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

PubMed

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 (74C), cooled in ice water, and stored at 4.4C 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

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

2011-02-01

35

Spoilage of sous vide cooked salmon (Salmo salar) stored under refrigeration.  

PubMed

The spoilage of Sous Vide 'SV' cooked salmon stored under refrigeration was studied. Samples were packaged under vacuum in polyamide-polypropylene pouches, cooked at an oven temperature/time of 80 ()C/45 min, quickly chilled at 3 ()C and stored at 2 ()C for 0, 5 or 10 weeks for catering use. Microbial (aerobic and anaerobic psychrotrophs, lactic acid bacteria, molds and yeasts and Enterobacteriaceae), physical-chemical (pH, water activity, TBARS, acidity, L*a*b* color, texture profile analysis and shear force) and sensory (appearance, odor, flavor, texture and overall quality) parameters were determined. SV processing prevented the growth of aerobic and anaerobic psychrotrophs, lactic acid bacteria, molds and yeasts and Enterobacteriaceae. There were no relevant changes in pH, water activity, TBARS, CIELab color associated with cooked salmon spoilage. Instrumental texture data were contradictory. Slight decrease in lactic acid levels was found. In contrast, the SV cooked salmon suffered considerable sensory deterioration during its refrigerated storage, consisting of severe losses of cooked salmon odor and flavor, slight rancidity, discoloration associated with white precipitation, and moderates softness, and loss of chewiness and juiciness. No acidification, putrefaction or relevant rancidity was detected. The sensory spoilage preceded microbiological and physical-chemical spoilage, suggesting that microbiological quality alone may overestimate the shelf life of SV cooked salmon. PMID:21364043

Daz, P; Garrido, M D; Ban, S

2011-02-01

36

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

NASA Astrophysics Data System (ADS)

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-Forts Enhance Geothermal System (EGS) located in the French part of the Upper Rhine Graben. The Soultz-sous-Forts 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-Forts. 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-Forts 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.

Heimlich, Christine; Masson, Frdric; Gourmelen, Nol

2014-05-01

37

Synthse dans les sels fondus de cristallites d'YBa2CU3O{7-x} et d'HoBa2CU3O{7-x} sous forme de plaquettes bien individualises et orientation sous champ magntique  

NASA Astrophysics Data System (ADS)

We studied the molten salt synthesis of YBa2CU3O{7-x} et HoBa2CU3O{7-x} phases. Best results have been obtained in an equimolar mixture of potassium and sodium chlorides. This technique leads to the formation of plate-shaped finely divided micronic crystallites. We investigated then the preparation of grain-oriented HoBa2CU3O{7-x} superconducting ceramics by a field-induced orientation method. The first results of the magnetic field orientation of a suspension by the slip casting technique are presented. Nous avons tudi la synthse en sel fondu des phases supraconductrices YBa2CU3O{7-x} et HoBa2CU3O{7-x}. Les meilleurs rsultats sont obtenus dans le mlange quimolaire des sels de chlorure de potassium et de sodium. Cette technique conduit la formation de cristallites de dimensions microniques sous forme de plaquettes finement divises. Nous avons ensuite entrepris l'laboration de cramiques supraconductrices orientes de la phase HoBa2CU3O{7-x} par une mthode d'orientation induite par un champ magntique. Nous prsentons les premiers rsultats de l'orientation sous champ magntique d'une barbotine par la technique de coule en moule poreux.

Bermis, P.; Chaudouet, P.; Weiss, F.; Snateur, J. P.; Joubert, J. C.

1991-11-01

38

17 `eme Congr`es Francais de Mecanique Troyes, septembre 2005 Une version sous-structuree de la TVRC pour le traitement de liaisons  

E-print Network

17 `eme Congr`es Franc�ais de M�ecanique Troyes, � septembre 2005 Une version sous-structur�ee de�canique, Troyes : France (2005)" #12;17 `eme Congr`es Franc�ais de M�ecanique Troyes, � septembre 2005 une analyse

39

BIODIVERSIT ET BIOMASSE DE LA FAUNE DU SOL SOUS CLIMAT English title: Biodiversity and biomass of soil fauna in temperate climate  

E-print Network

BIODIVERSIT? ET BIOMASSE DE LA FAUNE DU SOL SOUS CLIMAT TEMP?R?: English title: Biodiversity du sol, biomasse, biodiversité, zone tempérée Abstract and keywords: Forest soil animal biomass, biomass, biodiversity, temperate zones hal-00503100,version1-16Jul2010 Manuscrit auteur, publié dans

Paris-Sud XI, Université de

40

Dimensionnement des actionneurs lectriques aliments frquence variable sous faible tension  

NASA Astrophysics Data System (ADS)

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 premire partie nous avons dvelopp un modle d'analyse pluridisciplinaire qui tablissait les dpendances fonctionnelles entre les variables de conception et les performances magnto-lectro-thermiques d'un moteur brushless aimants permanents. Dans cet article nous dcrivons une procdure de dimensionnement adapte la conception de la machine alimente frquence variable sous faible tension. L'objectif est d'intgrer la dynamique du convertisseur lectronique ds la phase initiale du dimensionnement, au mme titre que les spcifications lectromcaniques et thermiques. La procdure est gre par une mthode d'optimisation dterministe de type Programmation Quadratique Squentielle. Elle intgre l'influence du convertisseur au moyen de deux spcificits : la premire consiste valuer les fonctions du problme d'optimisation sur la base du module d'analyse pluridisciplinaire ; la deuxime permet de contrler l'volution du dimensionnement au travers de variables d'optimisation dont la liste inclut les consignes de la commande en courant du convertisseur. Les difficults d'optimisation lies au mode de fonctionnement discret du convertisseur sont discutes au regard du calcul de la sensibilit du couple lectromagntique envers la consigne de courant du convertisseur ; une mthode est propose pour assurer la robustesse de la procdure en prsence du convertisseur. L'application porte sur le dimensionnement d'un moteur aimants permanents de type brushless trapzodal" destin la traction d'un scooter lectrique ; l'volution de la structure optimale avec le degr de complexit du module d'analyse est mise en vidence.

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

1999-09-01

41

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

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

Rochaix, Jean-David

42

Paru dans Voyager d'un point de vue nomade (sous la dir. de Hlne Claudot-Hawad), Paris, Editions Paris-Mditerrane, 2002, pp. 11-36  

E-print Network

1 Paru dans Voyager d'un point de vue nomade (sous la dir. de Hélène Claudot-Hawad), Paris, Editions Paris-Méditerranée, 2002, pp. 11-36 Noces de vent : épouser le vide ou l'art nomade de voyager par « le séjour, c'est le séjour ; le voyage, c'est le voyage », insiste sur l'opposition de « nature

Paris-Sud XI, Université de

43

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.

44

ion irradiation  

NASA Astrophysics Data System (ADS)

Fine Co and Pt nanoparticles are nucleated when a silica sample is implanted with 400 keV Co+ and 1370 keV Pt+ ions. At the implanted range, Co and Pt react to form small Co x Pt(1- x) nanoparticles during Si+ ion irradiation at 300 C. Thermal annealing of the pre-implanted silica substrate at 1000 C results in the formation of spherical nanoparticles of various sizes. When irradiated with Si+ ions at 300 C, particles in the size range of 5-17 nm undergo rod-like shape transformation with an elongation in the direction of the incident ion beam, while those particles in the size range of 17-26 nm turn into elliptical shape. Moreover, it is suspected that very big nanoparticles (size >26 nm) decrease in size, while small nanoparticles (size <5 nm) do not undergo any transformation. During Si+ ion irradiation, the crystalline nature of the nanoparticles is preserved. The results are discussed in the light of the thermal spike model.

Balaji, S.; Panigrahi, B. K.; Saravanan, K.; David, C.; Amirthapandian, S.; Kalavathi, S.; Nair, K. G. M.; Hbner, Ren

2014-09-01

45

Safer Food with Irradiation  

E-print Network

This publication answers questions about food irradiation and how it helps prevent foodborne illnesses. Included are explanations of how irradiation works and its benefits. Irradiation is a safe method of preserving food quality and ensuring its...

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

2003-01-21

46

Use of Irradiated Foods  

NASA Technical Reports Server (NTRS)

The safety of irradiated foods is reviewed. Guidelines and regulations for processing irradiated foods are considered. The radiolytic products formed in food when it is irradiated and its wholesomeness is discussed. It is concluded that food irradiation processing is not a panacea for all problems in food processing but when properly used will serve the space station well.

Brynjolfsson, A.

1985-01-01

47

Neutron irradiation of semiconductors  

Microsoft Academic Search

Electron irradiated GaAs-and Si-crystals were investigated to identify lattice defects, as a preparation for experiments on neutron irradiated Si and GaAs. The defects occurring after electron irradiation (E = 2MeV) are easier to analyze than after neutron irradiation. Moreover, beta emission from neutron transmutated GaAs and Si show effects which are very similar to the case of electron irradiation. Using

W. Ossau; U. Steigenberger; G. Landewehr; K. Elliott; P. L. Liu

1984-01-01

48

Cin?tique de la troponine Ic et valeurs seuils pour le diagnostic d'infarctus du myocarde apr?s chirurgie cardiaque sous circulation extracorporelle  

PubMed Central

Introduction L'objectif de ce travail tait dtudier la cintique de la Troponine Ic (TnIc) aprs chirurgie cardiaque sous circulation extracorporelle (CEC) et tablir des valeurs seuils de TnIc pour le diagnostic d'infarctus du myocarde (IDM) post opratoire. Il s'agissait d'une tude prospective type cohorte observationnelle. Mthodes Nous avons inclus 37 patients gs de plus de 18 ans proposs pour chirurgie valvulaire ou pontage aorto coronarien sous CEC. Nous avons suivi la cintique de TnIc par des dosages immunoenzymatique sur mini-vidas avant et aprs la CEC, H4 et H12 postopratoire puis tous les jours les 4 premiers jours. Le cutoff pour le diagnostic d'IDM post opratoire a t dfini comme la valeur moyenne de troponine + deux dviations standards des patients indemnes de complications cardiaques. Rsultats Les valeurs de TnIc en propratoire taient toutes infrieures au seuil de dtection de la mthode de dosage (<0,01g/l). Les valeurs de TnIc augmentent en postopratoire immdiat pour atteindre un maximum H4 puis diminuent progressivement pour se normaliser aprs 4 5 jours. Les valeurs seuils ont t dtermines pour H0, H4,H12, H24, H48, H72, H96 et ont t respectivement 1.36, 2.58, 3.1, 3.23, 2.13, 1.53, 1.17 pour la chirurgie coronaire et 3.75, 5.39, 4.22, 3.41, 1.65, 1.3 1.19 pour la chirurgie valvulaire. Conclusion La connaissance de la cintique de TnIc lors de chirurgie cardiaque non complique et la fixation de valeur seuil ou Cutoff permet aux cliniciens de distinguer entre dommage myocardique secondaire la chirurgie et IDM. PMID:23396754

Kallel, Samy; Jarraya, Anwar; Ellouze, Maged; Frikha, Imed; Karoui, Abbdelhamid

2012-01-01

49

Phototherapy irradiation chamber  

Microsoft Academic Search

A phototherapy irradiation chamber having substantial uniformity of irradiance therewithin comprises an array of vertical fluorescent lamps surrounding the irradiation space. Reflectors are located within the array at the top and bottom thereof. The ends of the lamps extend beyond the reflectors. 8 claims.

1978-01-01

50

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

NASA Astrophysics Data System (ADS)

The geothermal power plant of Soultz-sous-Forts 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.

Cal, Marco; Dorbath, Catherine

2013-08-01

51

Using numerical analysis to develop and evaluate the method of high temperature sous-vide to soften carrot texture in different-sized packages.  

PubMed

The high-temperature sous-vide (HTSV) method was developed to prepare carrots with a soft texture at the appropriate degree of pasteurization. The effect of heating conditions, such as temperature and time, was investigated on various package sizes. Heating temperatures of 70, 80, and 90 C and heating times of 10 and 20 min were used to evaluate the HTSV method. A 3-dimensional conduction model and numerical simulations were used to estimate the temperature distribution and the rate of heat transfer to samples with various geometries. Four different-sized packages were prepared by stacking carrot sticks of identical size (9.6 9.6 90 mm) in a row. The sizes of the packages used were as follows: (1) 9.6 86.4 90, (2) 19.2 163.2 90, (3) 28.8 86.4 90, and (4) 38.4 86.4 90 mm. Although only a moderate change in color (L*, a*, and b*) was observed following HTSV cooking, there was a significant decrease in carrot hardness. The geometry of the package and the heating conditions significantly influenced the degree of pasteurization and the final texture of the carrots. Numerical simulations successfully described the effect of geometry on samples at different heating conditions. PMID:24689882

Hong, Yoon-Ki; Uhm, Joo-Tae; Yoon, Won Byong

2014-04-01

52

Thermoluminescence of irradiated foodstuffs  

NASA Astrophysics Data System (ADS)

Measurements have been made of the thermoluminescent response of a number of foodstuffs, namely spices, chicken bone, eggshell and strawberries. From the results, irradiated samples can be clearly distinguished from unirradiated ones for several weeks after irradiation of 5-10 kGy, or in the case of some spices for up to 20 months. It is concluded that measurement of thermoluminescence is a promising technique for detecting the irradiation of foodstuffs.

Oduko, J. M.; Spyrou, N. M.

53

Comminuting irradiated ferritic steel  

DOEpatents

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.

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

1985-01-01

54

Comminuting irradiated ferritic steel  

SciTech Connect

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.

Bauer, R. E.; Chin, B. A.; Straalsund, J. L.

1985-03-26

55

Aseismic motions associated with fluid injections. The case study of the stimulation of GPK2 well at Soultz-sous-Forts, France  

NASA Astrophysics Data System (ADS)

Relationship between seismic and aseismic slips is a fundamental challenge for understanding and controling induced seismicity. In 2000, a large water injection has been conducted in granite through a 5-km-deep borehole at the Enhanced Geothermal System (EGS) site of Soultz-sous-Forts, in the Upper Rhine Graben (France). The microseismicity induced during the hydraulic stimulation was used by Calo' et al. (2011) to carry out a time-dependent P-waves seismic tomography of the stimulated region. Vp anomalies observed during stationary injection conditions are interpreted by the authors as being caused by effective stress variations linked to fluid diffusion, while the fast changes observed concomitantly to changes in flow rate are considered to be caused by non-seismic motions. We present a mechanical model of the stress field variations compatible with the seismic velocities observed during the hydraulic stimulation. The modeling is performed considering a fresh fracture region defined by the seismological information (the seismic cluster). The shear zone is loaded by pore pressure variations following the wellhead pressure trend recorded during the injection test. Results show that the variation of the maximum differential stress (?1 - ?3), in such conditions, reproduces patterns that match well the observed seismic velocity anomalies. Results from laboratory measurements are used for converting the calculated stress field variations into corresponding seismic velocities in order to compare the observed seismic velocities variations with those computed with the model. The proposed model suggests that time-dependent seismic tomography may provide a useful tool for observing the occurrence of large-scale aseismic slips during massive fluid injections.

Calo, M.; Cornet, H.; Dorbath, C.

2012-12-01

56

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

NASA Astrophysics Data System (ADS)

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-Forts (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.

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

2011-12-01

57

The ARBOR irradiation project  

NASA Astrophysics Data System (ADS)

The irradiation project 'ARBOR', for 'Associated Reactor Irradiation in BOR 60', includes 150 mini-tensile/low cycle fatigue specimens and 150 mini-Charpy (KLST) specimens of nine different RAFM steels. Specimens began irradiation on 22 November 2000 in an specially designed irradiation rig in BOR 60, in a fast neutron flux (>0.1 MeV) of 1.810 15 n/cm 2 s and with direct sodium cooling at a temperature less than 340 C. Tensile, low cycle fatigue and Charpy specimens of the following materials are included: EUROFER 97, F82H mod., OPTIFER IVc, EUROFER 97 with different boron contents, ODS-EUROFER 97, as well as EUROFER 97 electron-beam welded and reference bulk material, from NRG, Petten.

Petersen, C.; Shamardin, V.; Fedoseev, A.; Shimansky, G.; Efimov, V.; Rensman, J.

2002-12-01

58

The Birmingham Irradiation Facility  

NASA Astrophysics Data System (ADS)

At the end of 2012 the proton irradiation facility at the CERN PS [1] will shut down for two years. With this in mind, we have been developing a new ATLAS scanning facility at the University of Birmingham Medical Physics cyclotron. With proton beams of energy approximately 30 MeV, fluences corresponding to those of the upgraded Large Hadron Collider (HL-LHC) can be reached conveniently. The facility can be used to irradiate silicon sensors, optical components and mechanical structures (e.g. carbon fibre sandwiches) for the LHC upgrade programme. Irradiations of silicon sensors can be carried out in a temperature controlled cold box that can be scanned through the beam. The facility is described in detail along with the first tests carried out with mini (11 cm2) silicon sensors.

Dervan, P.; French, R.; Hodgson, P.; Marin-Reyes, H.; Wilson, J.

2013-12-01

59

IRRADIATED PETROLEUM RESINS  

Microsoft Academic Search

A method for improving the properties of polymeric material produced by ; the Friedel-Crafts polymerization of light, cracked petroleum fractions is ; presented. The petroleum resins are mixed with a divinyl aromatic and irradiated ; at a dose rate of at least 0.1 equivalent Mr\\/hr until at least 1\\/2 equivalent Mr ; is absorbed. Resinous solids are obtained that have

J. E. Shewmaker; J. F. Nelson

1963-01-01

60

Observations of solar irradiance variability  

Microsoft Academic Search

High-precision measurements of total solar irradiance, made by the active cavity radiometer irradiance monitor on the Solar Maximum Mission satellite, show the irradiance to have been variable throughout the first 153 days of observations. The corrected data resolve orbit-to-orbit variations with uncertainties as small as 0.001 percent. Irradiance fluctuations are typical of a band-limited noise spectrum with high-frequency cutoff near

R. C. Willson; M.. Janssen; H. S. Hudson; G. A. Chapman; S. Bulkis

1981-01-01

61

Solar irradiance since 1874 revisited  

Microsoft Academic Search

We reconstruct the solar irradiance since 1874 employing an evolved version of previously published models and improved sunspot and facular data. A good correlation between reconstructed irradiance and Earth's global air temperature on time scales longer than the solar cycle is obtained and, in contrast to many earlier models, solar irradiance does not on average lag behind global temperature prior

S. K. Solanki; M. Fligge

1998-01-01

62

4, 84398469, 2004 Solar irradiance  

E-print Network

ACPD 4, 8439­8469, 2004 Solar irradiance W. Gurlit et al. Title Page Abstract Introduction-A and visible solar irradiance spectrum: inter-comparison of absolutely calibrated, spectrally medium resolution solar irradiance spectra from balloon- and satellite-borne measurements W. Gurlit1 , H. B¨osch2, * , H

Paris-Sud XI, Université de

63

Irradiated brown dwarfs  

NASA Astrophysics Data System (ADS)

We have observed the post common envelope binary WD0137-349 in the near infrared J, H and K bands and have determined that the photometry varies on the system period (116 min). The amplitude of the variability increases with increasing wavelength, indicating that the brown dwarf in the system is likely being irradiated by its 16500 K white dwarf companion. The effect of the (primarily) UV irradiation on the brown dwarf atmosphere is unknown, but it is possible that stratospheric hazes are formed. It is also possible that the brown dwarf (an L-T transition object) itself is variable due to patchy cloud cover. Both these scenarios are discussed, and suggestions for further study are made.

Casewell, S. L.; Burleigh, M. R.; Lawrie, K. A.; Maxted, P. F. L.; Dobbie, P. D.; Napiwotzki, R.

64

Identification of irradiated foods  

SciTech Connect

A reliable method is needed to determine if foods have been irradiated and are in compliance with respect to the allowable absorbed radiation dose. Several approaches for the identification of irradiated foods are under development worldwide. These include measurement of o-tyrosine, radiolytically generated hydrocarbons from lipids and chemiluminescence or thermoluminescence, and the use of electron spin resonance (ESR) to measure free radicals trapped in calcified tissues. This paper describes the efforts being undertaken at the FDA to develop analytical procedures to monitor and identify foods that have been treated with ionizing radiation. In particular, it focuses on the use of an ESR approach to measure radiation-induced free radicals trapped in calcified tissues and the use of a capillary gas chromatography (GC)-based procedure to determine radiolytically generated hydrocarbons formed by the radiolysis of lipids in various foods.

Morehouse, K.M.

1992-01-01

65

[Radiodiagnosis and irradiated pregnancies].  

PubMed

An X-ray examination can sometimes be performed during the first few days of pregnancy. To prevent these accidental irradiations of the fetus, women must receive specific information about radiation effects, the ten Day Rule must be respected, and the physician must choose a non irradiating technique. X-ray examination may be performed in an emergency, especially if the examination is far from the pelvis. The radiologist must optimize the constants and decrease the number of films. The dose received depends on mAs, but other parameters are necessary for calculation (film source distance, kV, filtration...). For computed tomography, slice thickness, and interval between slices are taken in account. The dose received reaches a maximum after three axial sections, but is higher for a given area, than with conventional radiography. The irradiation effects depend on the fetal dose and the stage of pregnancy. Before implantation, the fetal dose is either ineffective or induces a miscarriage. During organogenesis, between the second and 16th week, doses exceeding 500 mGy can cause death of the fetus, malformations or growth retardation. We consider that when the dose is less than 100 mGy, they are no reasons to terminate the pregnancy. MRI does not seem to be dangerous for the course of pregnancy. No studies have demonstrated any teratogenic effects with intense magnetic fields. PMID:9846441

Foulquier, J N; Le Breton, C

1997-01-01

66

Post-irradiation effects in polyethylenes irradiated under various atmospheres  

NASA Astrophysics Data System (ADS)

If a large amount of polymer free radicals remain trapped after irradiation of polymers, the post-irradiation effects may result in a significant alteration of physical properties during long-term shelf storage and use. In the case of polyethylenes (PEs) some failures are attributed to the post-irradiation oxidative degradation initiated by the reaction of residual free radicals (mainly trapped in crystal phase) with oxygen. Oxidation products such as carbonyl groups act as deep traps and introduce changes in carrier mobility and significant deterioration in the PEs electrical insulating properties. The post-irradiation behaviour of three different PEs, low density polyethylene (LDPE), linear low density polyethylene (LLDPE) and high density polyethylene (HDPE) was studied; previously, the post-irradiation behaviour of the PEs was investigated after the irradiation in air (Suljovrujic, 2010). In this paper, in order to investigate the influence of different irradiation media on the post-irradiation behaviour, the samples were irradiated in air and nitrogen gas, to an absorbed dose of 300 kGy. The annealing treatment of irradiated PEs, which can substantially reduce the concentration of free radicals, is used in this study, too. Dielectric relaxation behaviour is related to the difference in the initial structure of PEs (such as branching, crystallinity etc.), to the changes induced by irradiation in different media and to the post-irradiation changes induced by storage of the samples in air. Electron spin resonance (ESR), differential scanning calorimetry (DSC), infra-red (IR) spectroscopy and gel measurements were used to determine the changes in the free radical concentration, crystal fraction, oxidation and degree of network formation, respectively.

Suljovrujic, E.

2013-08-01

67

Irradiation tests and post-irradiation examinations of DUPIC fuel  

Microsoft Academic Search

The technology of a DUPIC (Direct Use of spent PWR fuel In CANDU Reactors) fuel has been developed at KAERI for 10 years. To identify a robustness of the DUPIC fuel pellet, it has been irradiated for six times since August 1999 in HANARO. Among them, the first irradiation test was carried out with a simulated fuel. Therefore, a maximum

Chang Je Park; Kweon Ho Kang; Ho Jin Ryu; Cheol Yong Lee; In Ha Jung; Je Sun Moon; Joo Hwan Park; Sang Ho Na; Kee Chan Song

2008-01-01

68

Food irradiation and sterilization  

NASA Astrophysics Data System (ADS)

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 70-80C (bacon to 53C) 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 (-40C to -20C). 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.

Josephson, Edward S.

69

Correlation of irradiation data using activation fluences and irradiation temperature.  

NASA Technical Reports Server (NTRS)

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.

Lynch, J. H.

1971-01-01

70

Consumer acceptance of irradiated poultry.  

PubMed

A simulated supermarket setting (SSS) test was conducted to determine whether consumers (n = 126) would purchase irradiated poultry products, and the effects of marketing strategies on consumer purchase of irradiated poultry products. Consumer preference for irradiated poultry was likewise determined using a home-use test. A slide program was the most effective educational strategy in changing consumers' purchase behavior. The number of participants who purchased irradiated boneless, skinless breasts and irradiated thighs after the educational program increased significantly from 59.5 and 61.9% to 83.3 and 85.7% for the breasts and thighs, respectively. Using a label or poster did not increase the number of participants who bought irradiated poultry products. About 84% of the participants consider it either "somewhat necessary" or "very necessary" to irradiate raw chicken and would like all chicken that was served in restaurants or fast food places to be irradiated. Fifty-eight percent of the participants would always buy irradiated chicken if available, and an additional 27% would buy it sometimes. About 44% of the participants were willing to pay the same price for irradiated chicken as for nonirradiated. About 42% of participants were willing to pay 5% or more than what they were currently paying for nonirradiated chicken. Seventy-three percent or more of consumers who participated in the home-use test (n = 74) gave the color, appearance, and aroma of the raw poultry products a minimum rating of 7 (= like moderately). After consumers participated in a home-use test, 84 and 88% selected irradiated thighs and breasts, respectively, over nonirradiated in a second SSS test. PMID:7479506

Hashim, I B; Resurreccion, A V; McWatters, K H

1995-08-01

71

Electric fields in irradiated dielectrics  

NASA Technical Reports Server (NTRS)

An existing model for quantitatively predicting electric field build-up in dielectrics is used to demonstrate the importance of material parameters. Results indicate that electron irradiation will produce 10 to the 6th power V/cm in important materials. Parameters which can alter this build-up are discussed. Comparison to known irradiation induced dielectric charging experiments is discussed.

Frederickson, A. R.

1979-01-01

72

Commercial implementation of food irradiation  

NASA Astrophysics Data System (ADS)

In July 1981, the first specifically designed multi-purpose irradiation facility for food irradiation was put into service by the Radiation Technology, Inc. subsidiary Process Technology, Inc. in West Memphis, Arkansas. The operational experience gained, resulted in an enhanced design which was put into commercial service in Haw River, North Carolina, by another subsidiary, Process Technology (N.C.), Inc. in October 1983. These facilities have enabled the food industry to assess the commercial viability of food irradiation. Further impetus towards commercialization of food irradiation was gained in March 1981 with the filing in the Federal Register, by the FDA, of an Advanced Proposed Notice of Rulemaking for Food Irradiation. Two years later in July 1983, the FDA approved the first food additive regulation involving food irradiation in nineteen years, when they approved the Radiation Technology, Inc. petition calling for the sanitization of spices, onion powder and garlic powder at a maximum dosage of 10 kGy. Since obtaining the spice irradiation approval, the FDA has accepted four additional petitions for filing in the Federal Register. One of the petitions which extended spice irradiation to include insect disinfestation has issued into a regulation while the remaining petitions covering the sanitization of herbs, spice blends, vegetable seasonings and dry powdery enzymes as well as the petition to irradiate hog carcasses and pork products for trichinae control at 1 kGy, are expected to issue either before the end of 1984 or early in 1985. More recently, food irradiation advocates in the United States received another vote of confidence by the announcement that a joint venture food irradiation facility to be constructed in Hawaii by Radiation Technology, is backed by a contractual committment for the processing of 40 million pounds of produce per year. Another step was taken when the Port of Salem, New Jersey announced that the Radiation Technology Model RT-4104-4048(TM) irradiation facility was chosen to interface with the only East Coast grain elevator in the United States. These factors, along with concern over the ban of EDB as a post harvest fumigant, coupled with the expected FDA action to approve the use of irradiation for the insect disinfestation of fruit and vegetables, should finally permit the commercial implementation of food irradiation to take hold in the United States.

Welt, M. A.

73

Proton irradiation of simple gas mixtures: Influence of irradiation parameters  

NASA Technical Reports Server (NTRS)

In order to get information about the influence of irradiation parameters on radiolysis processes of astrophysical interest, methane gas targets were irradiated with 6.5 MeV protons at a pressure of 1 bar and room temperature. Yields of higher hydrocarbons like ethane or propane were found by analysis of irradiated gas samples using gas chromatography. The handling of the proton beam was of great experimental importance for determining the irradiation parameters. In a series of experiments current density of the proton beam and total absorbed energy were shown to have a large influence on the yields of produced hydrocarbons. Mechanistic interpretations of the results are given and conclusions are drawn with regard to the chemistry and the simulation of various astrophysical systems.

Sack, Norbert J.; Schuster, R.; Hofmann, A.

1990-01-01

74

Accelerated partial breast irradiation.  

PubMed

Local therapies to treat newly diagnosed breast cancer include a lumpectomy with radiation therapy or a mastectomy. The 20-year data from studies about the safety and efficacy of lumpectomy with full-breast radiation therapy support the safety of this regimen and its role to decrease the risk of ipsilateral recurrence and increase long-term survivorship of women with breast cancer. Accelerated partial breast irradiation (APBI) provides radiation therapy to the tumor bed but spares the remaining breast tissue. APBI accelerates the time required to complete the therapy regimen, with a range of one intraoperative session to five consecutive days compared to five to seven weeks. Several techniques exist to administer APBI, including the insertion of a balloon into the lumpectomy space. Of interest is the widespread use of APBI in community and academic settings that has preceded outcomes of large, randomized clinical trials. Because of selection bias in a number of small, single-institution, nonrandomized studies, published data are of limited value to ensure APBI as a standard of care. PMID:25253109

Bauer, Elfrida; Lester, Joanne L

2014-10-01

75

(Irradiation creep of graphite)  

SciTech Connect

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.

Kennedy, C.R.

1990-12-21

76

Generic phytosanitary irradiation treatments  

NASA Astrophysics Data System (ADS)

The history of the development of generic phytosanitary irradiation (PI) treatments is discussed beginning with its initial proposal in 1986. Generic PI treatments in use today are 150 Gy for all hosts of Tephritidae, 250 Gy for all arthropods on mango and papaya shipped from Australia to New Zealand, 300 Gy for all arthropods on mango shipped from Australia to Malaysia, 350 Gy for all arthropods on lychee shipped from Australia to New Zealand and 400 Gy for all hosts of insects other than pupae and adult Lepidoptera shipped to the United States. Efforts to develop additional generic PI treatments and reduce the dose for the 400 Gy treatment are ongoing with a broad based 5-year, 12-nation cooperative research project coordinated by the joint Food and Agricultural Organization/International Atomic Energy Agency Program on Nuclear Techniques in Food and Agriculture. Key groups identified for further development of generic PI treatments are Lepidoptera (eggs and larvae), mealybugs and scale insects. A dose of 250 Gy may suffice for these three groups plus others, such as thrips, weevils and whiteflies.

Hallman, Guy J.

2012-07-01

77

Food irradiation and combination processes  

NASA Astrophysics Data System (ADS)

International approval of food irradiation is being given for the use of low and medium doses. Uses are being permitted for different categories of foods with maximum levels being set between 1 and 10 kGy. To maximize the effectiveness of these mild irradiation treatments while minimizing any organoleptic quality changes, combination processes of other technologies with irradiation will be useful. Combinations most likely to be exploited in optimal food processing include the use of heat, low temperature, and modified-atmosphere packaging. Because irradiation does not have a residual effect, the food packaging itself becomes an important component of a successful process. These combination processes provide promising alternatives to the use of chemical preservatives or harsher processing techniques.

Campbell-Platt, G.; Grandison, A. S.

78

Irradiation pretreatment for coal desulfurization  

NASA Technical Reports Server (NTRS)

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.

Hsu, G. C.

1979-01-01

79

Weld repair of irradiated materials  

SciTech Connect

Maintenance of an accelerator for production of tritium will require replacement or modification of components that have been exposed to neutron irradiation. A primary repair option is welding, but conventional repair welding processes produced severe cracking in irradiated stainless steel. Optical metallography, scanning electron microscopy, and transmission electron microscopy have shown that the cracks are: intergranular, primarily in the weld heat-affected zone, characterized by a dimple structure on the crack surface, and associated with helium bubbles that grow during welding. A model has been developed that qualitatively shows the interaction of three primary and three secondary variables producing helium embrittlement cracking. A shallow penetration overlay technique was successfully demonstrated to minimize cracking in irradiated 304 stainless steel that contained 10 appm helium. The overlay technique provides a potential method for repair or modification of accelerator materials exposed to irradiation.

Kanne, W.R. Jr.; Louthan, M.R. Jr.; Rankin, D.T.; Tosten, M.H.

1999-09-01

80

Weld Repair of Irradiated Materials  

SciTech Connect

Maintenance of an accelerator for production of tritium will require replacement or modification of components that have been exposed to neutron irradiation. A primary repair option is welding, but conventional repair welding processes produced severe cracking in irradiated stainless steel. Optical metallography, scanning electron microscopy, and transmission electron microscopy have shown that the cracks are: intergranular, primarily in the weld heat-affected zone, characterized by a dimple structure on the crack surface, and associated with helium bubbles which grow during welding. A model has been developed which qualitatively shows the interaction of three primary and three secondary variables producing helium embrittlement cracking. A shallow penetration overlay technique was successfully demonstrated to minimize cracking in irradiated 304 stainless steel that contained 10 appm helium. The overlay technique provides a potential method for repair or modification of accelerator materials exposed to irradiation.

Kanne, W.R. Jr.

1999-02-24

81

Calculating Irradiance For Photosynthesis In The Ocean  

NASA Technical Reports Server (NTRS)

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.

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

1990-01-01

82

The LASP Interactive Solar IRradiance Datacenter (LISIRD)  

Microsoft Academic Search

The Laboratory for Atmospheric and Space Physics (LASP) has been making space-based measurements of solar irradiance for many decades, and thus has established an extensive catalog of past and ongoing space- based solar irradiance measurements. In order to maximize the accessibility and usability of solar irradiance data and information from multiple missions, LASP is developing the LASP Interactive Solar IRradiance

C. K. Pankratz; D. M. Lindholm; M. Snow; B. Knapp; D. Woodraska; B. Templeman; T. N. Woods; F. G. Eparvier; J. Fontenla; J. Harder; W. E. McClintock

2007-01-01

83

Thermal expansion of irradiated polytetrafluoroethylene  

Microsoft Academic Search

Synopsis The thermal expansion coefficient of gamma-irradiated Polytetrafluoroethylene (FTFE) has been measured in the temperature range 80-340 K by using a three-terminal capacitance technique. The samples are irradiated in air at room temperature with gamma rays from a Cow source at a dose rate of 0.26 Mrad\\/h. The change in crystallinity is measured by an x-ray technique. The expansion coefficient

H. N. Subrahmanyam; S. V. Subramanyam

1987-01-01

84

Irradiation Stability of Carbon Nanotubes  

E-print Network

the tubes and adjust their diameters [11-17]. ____________ This thesis follows the style of Nuclear Instruments & Methods in Physics Research B. 2 As a result of irradiation, formation of unique pentagon/heptagon Stone-Wales defects can occur... the tubes and adjust their diameters [11-17]. ____________ This thesis follows the style of Nuclear Instruments & Methods in Physics Research B. 2 As a result of irradiation, formation of unique pentagon/heptagon Stone-Wales defects can occur...

Aitkaliyeva, Assel

2010-01-14

85

Slag recycling of irradiated vanadium  

SciTech Connect

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.

Gorman, P.K.

1995-04-05

86

Consumer attitudes toward irradiated food  

SciTech Connect

Throughout history, new methods of food preservation have been met with skepticism and fear. Such processes as pasteurization and canning were denounced as being dangerous, detrimental to nutrients, or an excuse for dirty products. Now comes irradiation, and activists argue against this new process for the same reasons. Publicly, the perception is that consumers, distrustful of nuclear power, will never buy or accept irradiated food.

Conley, S. [USDA, Washington, DC (United States)

1994-12-31

87

before and after gamma irradiation  

NASA Astrophysics Data System (ADS)

A series of samples of HoFe1- x Ni x O3 ( x = 0.0, 0.1, 0.3) were prepared using the solid-state reaction technique to understand the structural, dielectric and conductivity properties before and after gamma irradiation of accumulated dose of 625 KGy. The X-ray diffraction confirms that all the samples exist in single-phase orthorhombic structure having space group Pbnm. With increasing dopant Ni, the unit cell volume and lattice parameters undergo small change. X-ray analysis show change in the interplanar spacing and full width at half maximum values after gamma irradiation. The Raman spectra of the samples show modifications after gamma irradiation. It can be easily seen that after gamma irradiation intensity, peak width are completely altered by gamma-absorbed dose. Measurement of dielectric loss and dielectric constant at room temperature was performed before and after gamma irradiation in the frequency range of 20 Hz-1 MHz. It is observed that the value of dielectric constant decreases after irradiation. The ac conductivity is estimated from the dielectric constant and loss tangent. Exposure to gamma radiation results in substantial modification in the physical properties of the Ni-doped Ho-based orthoferrites.

Habib, Zubida; Ikram, M.; Majid, Kowsar; Asokan, K.

2014-09-01

88

Food irradiation: Public opinion surveys  

SciTech Connect

The Canadian government are discussing the legislation, regulations and practical protocol necessary for the commercialization of food irradiation. Food industry marketing, public relations and media expertise will be needed to successfully introduce this new processing choice to retailers and consumers. Consumer research to date including consumer opinion studies and market trials conducted in the Netherlands, United States, South Africa and Canada will be explored for signposts to successful approaches to the introduction of irradiated foods to retailers and consumers. Research has indicated that the terms used to describe irradiation and information designed to reduce consumer fears will be important marketing tools. Marketers will be challenged to promote old foods, which look the same to consumers, in a new light. Simple like or dislike or intention to buy surveys will not be effective tools. Consumer fears must be identified and effectively handled to support a receptive climate for irradiated food products. A cooperative government, industry, health professional, consumer association and retailer effort will be necessary for the successful introduction of irradiated foods into the marketplace. Grocery Products Manufacturers of Canada is a national trade association of more than 150 major companies engaged in the manufacture of food, non-alcoholic beverages and array of other national-brand consumer items sold through retail outlets.

Kerr, S.D.

1987-01-01

89

Helioseismic Limits on Irradiance Variations  

NASA Astrophysics Data System (ADS)

Changes in the frequencies of solar oscillations are the most precise probe of irradiance variations over the solar cycle. Using MDI data, Dziembowski and Goode (2005) showed that f-mode changes arise from the direct effect of the evolving magnetic activity, while p-mode changes are due to small, activity induced changes in convective flows very near to the solar surface (turbulent pressure). The f-modes also sharply limit the allowed field growth with activity, and the limit is consistent with the observations of Lin and Rimmele (1999). Combining MDI data with BBSO Ca II K, we find the Sun is smooth at activity minimum and becomes increasingly corrugated with rising activity. The overall physical picture is one in which the Sun is hottest and smoothest at activity minimum, and becomes cooler, more corrugated and irradiant with rising activity. These results place a lower limit on irradiance variations and are roughly consistent with a picture of Spruit (2000).

Goode, P. R.

2005-05-01

90

Healing in the irradiated wound  

SciTech Connect

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.

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

1990-07-01

91

Irradiation Effects on Substructure Related to Irradiation Softening.  

National Technical Information Service (NTIS)

The evolution of the dislocation microstructure during irradiation of a deformed Fe-2 1/4 Cr-1Mo ferritic alloy was characterized by two competing processes. At low temperature, the dislocation density increased due to loop formation and interaction. At h...

J. L. Brimhall, E. P. Simonen

1985-01-01

92

Antitumor immunity induced after ? irradiation.  

PubMed

Radioimmunotherapy (RIT) is a therapeutic modality that allows delivering of ionizing radiation directly to targeted cancer cells. Conventional RIT uses ?-emitting radioisotopes, but recently, a growing interest has emerged for the clinical development of ? particles. ? emitters are ideal for killing isolated or small clusters of tumor cells, thanks to their specific characteristics (high linear energy transfer and short path in the tissue), and their effect is less dependent on dose rate, tissue oxygenation, or cell cycle status than ? and X rays. Several studies have been performed to describe ? emitter radiobiology and cell death mechanisms induced after ? irradiation. But so far, no investigation has been undertaken to analyze the impact of ? particles on the immune system, when several studies have shown that external irradiation, using ? and X rays, can foster an antitumor immune response. Therefore, we decided to evaluate the immunogenicity of murine adenocarcinoma MC-38 after bismuth-213 ((213)Bi) irradiation using a vaccination approach. In vivo studies performed in immunocompetent C57Bl/6 mice induced a protective antitumor response that is mediated by tumor-specific T cells. The molecular mechanisms potentially involved in the activation of adaptative immunity were also investigated by in vitro studies. We observed that (213)Bi-treated MC-38 cells release "danger signals" and activate dendritic cells. Our results demonstrate that ? irradiation can stimulate adaptive immunity, elicits an efficient antitumor protection, and therefore is an immunogenic cell death inducer, which provides an attractive complement to its direct cytolytic effect on tumor cells. PMID:24862758

Gorin, Jean-Baptiste; Mnager, Jrmie; Gouard, Sbastien; Maurel, Catherine; Guilloux, Yannick; Faivre-Chauvet, Alain; Morgenstern, Alfred; Bruchertseifer, Frank; Chrel, Michel; Davodeau, Franois; Gaschet, Jolle

2014-04-01

93

FFTF utilization for irradiation testing  

Microsoft Academic Search

FFTF utilization for irradiation testing is beginning. Two Fuels Open Test Assemblies and one Vibration Open Test Assembly, both containing in-core contact instrumentation, are installed in the reactor. These assemblies will be used to confirm plant design performance predictions. Some 100 additional experiments are currently planned to follow these three. This will result in an average core loading of about

D. C. Corrigan; L. J. Julyk; C. W. Hoth; J. C. McGuire; W. R. Sloan

1980-01-01

94

sterilization by irradiation Arne Miller  

E-print Network

;4 Equipment characterization (6.2) Description of irradiation facility (6.2) Characteristic parameters Layout Layout #12;13 OQ gamma cont.. Gamma Facility Layout #12;14 Modelling Monte Carlo calculations Wednesday of the facility #12;11 Operational qualification Gamma · dose distribution in reference product(s) · dose

95

Evaluation of irradiation hardening of proton irradiated stainless steels by nanoindentation  

NASA Astrophysics Data System (ADS)

Ion irradiation experiments are useful for investigating irradiation damage. However, estimating the irradiation hardening of ion-irradiated materials is challenging because of the shallow damage induced region. Therefore, the purpose of this study is to prove usefulness of nanoindentation technique for estimation of irradiation hardening for ion-irradiated materials. SUS316L austenitic stainless steel was used and it was irradiated by 1 MeV H+ ions to a nominal displacement damage of 0.1, 0.3, 1, and 8 dpa at 573 K. The irradiation hardness of the irradiated specimens were measured and analyzed by Nix-Gao model. The indentation size effect was observed in both unirradiated and irradiated specimens. The hardness of the irradiated specimens changed significantly at certain indentation depths. The depth at which the hardness varied indicated that the region deformed by the indenter had reached the boundary between the irradiated and unirradiated regions. The hardness of the irradiated region was proportional to the inverse of the indentation depth in the Nix-Gao plot. The bulk hardness of the irradiated region, H0, estimated by the Nix-Gao plot and Vickers hardness were found to be related to each other, and the relationship could be described by the equation, HV = 0.76H0. Thus, the nanoindentation technique demonstrated in this study is valuable for measuring irradiation hardening in ion-irradiated materials.

Yabuuchi, Kiyohiro; Kuribayashi, Yutaka; Nogami, Shuhei; Kasada, Ryuta; Hasegawa, Akira

2014-03-01

96

ELECTRON MICROSCOPE STUDIES OF IRRADIATED BERYLLIUM METAL  

Microsoft Academic Search

When beryllium is irradiated by fast neutrons, helium is produced by the ; (n,2n) and (n, alpha ) transmutation reactions. Electron microscopy techniques ; were used to study the nucleation and distribution of helium bubbles in several ; different grades of beryllium, after irradiation at temperatures in the range 75 ; to 700 deg C. The effect of post-irradiation annealing

Chute

1963-01-01

97

Biological effects of ultraviolet irradiation on bees  

SciTech Connect

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.

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

1995-09-01

98

SIPS: Solar Irradiance Prediction System Stefan Achleitner  

E-print Network

SIPS: Solar Irradiance Prediction System Stefan Achleitner Computer Science and Engineering the variability and dynamics are the largest. We propose SIPS, Solar Irradiance Prediction System, a novel sensing infrastructure using wireless sensor networks (WSNs) to enable sensing of solar irradiance for solar power

Cerpa, Alberto E.

99

Total Solar Irradiance Variability: A Review  

NASA Technical Reports Server (NTRS)

Observations of total solar irradiance from space within the last two decaades convinced the skeptics that total irradiance varies over a wide range of periodicities: from minutes to the 11-year solar activity cycle. Analyses based on these space-borne observations have demonstrated that the irradiance variations are directly related to changes at the photosphere and the solar interior.

Pap, Judit M.

1996-01-01

100

Hepatobiliary kinetics after whole-body irradiation  

SciTech Connect

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.

Durakovic, A.

1986-09-01

101

Analyzing irradiation -induced creep of silicon carbide  

SciTech Connect

Irradiation creep, which is among the major lifetime-limiting mechanisms for nuclear structural materials, is stress-driven anisotropic plastic deformation occurring in excess of thermal creep deformation in radiation environments. In this work, experimental irradiation creep data for beta-phase silicon carbide (SiC) irradiated at intermediate temperatures is analyzed using a kinetic model with an assumed linear-coupling of creep strain rate with the rate of self interstitial atom (SIA) absorption at SIA clusters. The model reasonably explains the experimentally observed time-dependent creep rate of ion-irradiated SiC and swelling evolution of ion- and neutron-irradiated SiC. Bend stress relaxation behavior during irradiation was then simulated using the developed model to examine the experimental data obtained by neutron irradiation experiments. Recommended directions of future experiment are provided to further verify and improve the models and assumptions in this work.

Katoh, Yutai [ORNL; Snead, Lance Lewis [ORNL; Golubov, Stanislav I [ORNL

2007-01-01

102

Future Satellite Observations of Solar Irradiance  

NASA Technical Reports Server (NTRS)

Required solar irradiance measurements for climate studies include those now being made by the Total Irradiance Monitor (TIM) and the Spectral Irradiance Monitor (SIM) onboard the SORCE satellite, part of the Earth Observing System fleet of NASA satellites. Equivalent or better measures of Total Solar Irradiance (TSI) and Spectral Solar Irradiance (SSI, 200 to 2000 nm) are planned for the post-2010 satellites of the National Polar-orbiting Operational Environmental Satellite System ("OESS). The design life of SORCE is 5 years, so a "Solar Irradiance Gap Filler" EOS mission is being planned for launch in the 2007 time frame, to include the same TSI and SSI measurements. Besides avoiding any gap, overlap of the data sources is also necessary for determination of possible multi-decadal trends in solar irradiance. We discuss these requirements and the impacts of data gaps, and data overlaps, that may occur in the monitoring of the critical solar radiative forcing.

Cahalan, R. F.; Rottman, G.; Woods, T.; Lawrence, G.; Harder, J.; McClintock, W.; Kopp, G.

2003-01-01

103

GTL-1 Irradiation Summary Report  

SciTech Connect

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.

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

2012-01-01

104

Food irradiation development in Pakistan  

NASA Astrophysics Data System (ADS)

The large scale trials were held to extend the storage life of potatoes, onions and dry fruits by gamma radiation. It was concluded that radiation preservation of potatoes and onions was much cheaper as compared to conventional methods. A dose of 1 kGy can control the insects in dry fruits and nuts. The consumers' acceptability and market testing performed during the last four years are also conducive to the commercialization of the technology in this country. The Government of Pakistan has accorded clearance for the irradiation of some food items like potatoes, onions, garlic and spices for human consumption. The Pakistan Radiation Services (PARAS), the commercial irradiator (200 Kci) at Lahore, has already started functioning in April, 1987. It is planned to start large scale sterilization of spices by gamma radiation in PARAS shortly.

Khan, I.

105

RERTR-6 Irradiation Summary Report  

SciTech Connect

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.

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

2011-12-01

106

RERTR-8 Irradiation Summary Report  

SciTech Connect

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.

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

2011-12-01

107

RERTR-13 Irradiation Summary Report  

SciTech Connect

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.

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

2012-09-01

108

Licensing a new industrial irradiator.  

PubMed

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

Bates, Nicolas K; Entwistle, Frederick B

2010-02-01

109

Early esophageal carcinoma treated with intracavitary irradiation  

SciTech Connect

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.

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

1985-08-01

110

Thermal analysis applied to irradiated propolis  

NASA Astrophysics Data System (ADS)

Propolis is a resinous hive product, collected by bees. Raw propolis requires a decontamination procedure and irradiation appears as a promising technique for this purpose. The valuable properties of propolis for food and pharmaceutical industries have led to increasing interest in its technological behavior. Thermal analysis is a chemical analysis that gives information about changes on heating of great importance for technological applications. Ground propolis samples were 60Co gamma irradiated with 0 and 10 kGy. Thermogravimetry curves shown a similar multi-stage decomposition pattern for both irradiated and unirradiated samples up to 600C. Similarly, through differential scanning calorimetry , a coincidence of melting point of irradiated and unirradiated samples was found. The results suggest that the irradiation process do not interfere on the thermal properties of propolis when irradiated up to 10 kGy.

Matsuda, Andrea Harumi; Machado, Luci Brocardo; del Mastro, Nlida Lucia

2002-03-01

111

(Irradiation embrittlement of reactor pressure vessels)  

SciTech Connect

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.

Corwin, W.R.

1990-09-24

112

Irradiated food: Is there a need?  

SciTech Connect

Economic, medical, social, and technical issues related to the irradiation of food with nuclear gamma rays from radioactive sources are discussed in this article. Reasons cited for considering food irradiation include food loss due to spoilage and food-borne illnesses. Research studies investigating the effects of irradiation on the formation of carcinogens and radiolytics, and on the nutritional value of food are summarized. The support of international organizations and political aspects in the United States are also discussed in some detail.

Cohen, B.L. [Univ. of Pittsburgh, PA (United States)

1992-06-01

113

Interstitial defects involving boron in irradiated silicon  

Microsoft Academic Search

Silicon containing high concentrations of boron has been irradiated with 2 MeV electrons at room temperature. Initially, substitutional boron atoms are displaced into interstitial sites, but with prolonged irradiation there is a further interaction between B(i) and an intrinsic defect which is believed to be the Si(i). A similar effect is found in n0-irradiated samples. A broad absorption band is

K. Laithwaite; R. C. Newman; D. H. J. Totterdell

1975-01-01

114

Electron spin resonance identification of irradiated fruits  

NASA Astrophysics Data System (ADS)

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.

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

115

Irradiation creep\\/swelling interactions. [SS304  

Microsoft Academic Search

Results of a recent fast flux neutron irradiation experiment in EBR-II designed to determine the effects of high levels of prior irradiation (to 10n\\/cm, E greater than 0.1 MeV) on the irradiation induced deformation rate of 304 SS at 800F are reported. The data are analyzed in terms of a model which includes enhancement of creep with increasing swelling rates.

G. L. Wire; J. L. Straalsund

1975-01-01

116

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

NASA Astrophysics Data System (ADS)

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.

Lappan, Uwe; Geiler, Uwe; Gohs, Uwe; Uhlmann, Steffi

2010-10-01

117

Penile reconstruction in irradiated patient.  

PubMed

Reconstruction of a penis using a modified Gillies technique was performed on a forty-one-year-old man who had a total penectomy, inguinal node dissection, and 6,000 rads of cobalt-60 irradiation for carcinoma of the penis. The three different surgical techniques for reconstructing the penis are discussed in detail. It is our belief that reconstruction of a urethra and placement of a baculum in penile reconstruction after radiation therapy have more disadvantages than advantages. The literature is reviewed. PMID:1265946

Boxer, R J; Miller, T A

1976-04-01

118

Healing burns using atmospheric pressure plasma irradiation  

NASA Astrophysics Data System (ADS)

An experiment testing the effects of plasma irradiation with an atmospheric-pressure plasma (APP) reactor on rats given burns showed no evidence of electric shock injuries upon pathology inspection of the irradiated skin surface. In fact, the observed evidence of healing and improvement of the burns suggested healing effects from plasma irradiation. The quantities of neovascular vessels in the living tissues at 7 days were 9.2 0.77 mm-2 without treatment and 18.4 2.9 mm-2 after plasma irradiation.

Hirata, Takamichi; Kishimoto, Takumi; Tsutsui, Chihiro; Kanai, Takao; Mori, Akira

2014-01-01

119

Le Nigeria sous Obasanjo. Violences et dmocratie  

E-print Network

'Organisation mondiale contre la torture estime que 10 000 personnes seraient décédées au cours de conflits ethniques période 1999-2006. Voir World Organisation against Torture (OMCT) et Centre for Law Enforcement (Cleen

Paris-Sud XI, Université de

120

Famille : Fabaceae Sous-famille : Mimosoideae  

E-print Network

ensuite en phyllode de grande taille (11 à 27 cm de long sur 3 à 10 cm de large) caractérisé par quatre (3 bipennée au phyllode L.S.T.M. Phyllodes de Acacia mangium D.Louppe Coupe dans un nodule de Acacia mangium

Paris-Sud XI, Université de

121

sous la direction de Julian Wiethold  

E-print Network

archéologique européen,et le Centre de Recherches Archéologiques de laVallée de l'Oise (CRAVO),9-12 juin 2005Vallée de l'Oise (CRAVO),9-12 juin 2005,Glux-en-Glenne. Glux-en-Glenne :Bibracte,2011,254 pages,125 ill MATTERNE (UMR 7041,CRAVO,Inrap,Compiègne ­ F) Wilko N?LKEN (doctorant

Jacomet, Stefanie

122

La production industrielle sous la IVe Rpublique  

Microsoft Academic Search

[fre] A partir d'un instrument nouveau, les comptes trimestriels de la priode 1946-1962, cet article essaie de dcrire les fluctuations conomiques du systme productif pendant la quatrime rpublique. Il est centr uniquement sur les branches nergtiques (combustibles minraux solides et gaz, lectricit, ptrole, gaz naturel et carburants) et sur les branches industrielles (mines de fer et sidrurgie, minerais et mtaux

Michel Catinat

1981-01-01

123

Sodium and potassium levels in the serum of acutely irradiated and non-irradiated rats  

E-print Network

SODIUM AND POTASSIUM LEVELS IN THE SERUM OF ACUTELY IRRADIATED AND NON-IRRADIATED RATS A Thesis By DAVID PRESTON SHEPHERD Submitted to the Graduate College of the Texas ARM University in partial fulfillment of the requirements for the degree... of MASTER OF SCIENCE August 1967 Major Subject: Zoology SODIUM AND POTASSIUM LEVELS IN THE SERUM OF ACUTELY IRRADIATED AND NON-IRRADIATED RATS A Thesis By DAVID PRESTON SHEPHERD Approved as to style and content by: (Chairman of Committee) (Head...

Shepherd, David Preston

2012-06-07

124

Comparison of irradiation creep and swelling of an austenitic alloy irradiated in FFTF and PFR  

SciTech Connect

comparative irradiation of identically constructed creep tubes in the Fast Flux Test Facility (FFTF) and the Prototypic Fast Reactor (PFR) shows that differences in irradiation conditions arising from both reactor operation and the design of the irradiation vehicle can have a significant impact on the void swelling and irradiation creep of austenitic stainless steels. In spite of these differences, the derived creep coefficients fall within the range of previously observed values for 316 SS.

Garner, F.A. [Battelle Pacific Northwest Lab., Richland, WA (United States); Toloczko, M.B. [Washington State Univ., Pullman, WA (United States); Munro, B.; Adaway, S. [AEA Technology (United Kingdom); Standring, J. [UKAEA (United Kingdom)

1999-10-01

125

MEASUREMENT OF HIGH TEMPERATURE IRRADIATION CREEP IN GRAPHITE. Project DRAGON  

Microsoft Academic Search

As part of the joint Dragon\\/THTR graphite irradiation programme, experimental techniques have been evolved for measuring the irradiation creep of graphite at high temperatures. The principle of the method is to retrain the irradiation induced dimensional changes to produce a stressed assembly which gives rise to irradiation creep phenomena in the different components. Its main advantage is that little irradiation

Blackstone

1968-01-01

126

Solar Irradiance Data Products at the LASP Interactive Solar IRradiance Datacenter (LISIRD)  

Microsoft Academic Search

The Laboratory for Atmospheric and Space Physics (LASP) has developed the LASP Interactive Solar IRradiance Datacenter (LISIRD) to provide access to a comprehensive set of solar irradiance measurements. LISIRD has recently been updated to serve many new datasets and models, including data from SORCE, UARS-SOLSTICE, SME, and TIMED-SEE, and model data from the Flare Irradiance Spectral Model (FISM). The user

A. Ware Dewolfe; A. Wilson; D. M. Lindholm; C. K. Pankratz; M. A. Snow; T. N. Woods

2010-01-01

127

Fullerene ion irradiation to silicon  

NASA Astrophysics Data System (ADS)

Silicon has been irradiated by singly charged C 60 fullerene ions with an ion dose of up to 1 10 13 ions/cm 2 at room temperature in order to study the damage formation of cluster ion bombardment on solid surfaces. Singly and doubly charged fullerene ions and some daughter ions of fullerene were observed. Mass separation was accomplished by a 90 sector magnet. The maximum current of the mass-separated singly charged C 60 fullerene ion beam was about 10 nA. RBS (Rutherford backscattering spectrometry) channeling measurement of the Si(100) bombarded by 300 keV C 60 ions (i.e. 5.0 keV per carbon atom) shows a remarkable increase in the surface peak of the defects even at the low atomic dose of 6 10 14 atoms/cm 2. The C 60 fullerene ion beam irradiation produced many defects. This is one of the typical non-linear effects of cluster bombardment.

Tanomura, M.; Takeuchi, D.; Matsuo, J.; Takaoka, G. H.; Yamada, I.

1997-01-01

128

A SU-8 dish for cell irradiation  

NASA Astrophysics Data System (ADS)

The objective of the CELLION project is radiation research at low doses. The main cell responses to low dose irradiation are bystander effects, genomic instability and adaptive responses. In order to study these effects it is convenient to make the cells addressable in space and time through locking the cell position. A new alternative dish has been developed for irradiation procedures at the Lund Nuclear Probe. The versatile dish can be used both to cultivate and to hold the cells during the irradiation procedure. The irradiation dish is made of an epoxy-based photopolymer named SU-8 chosen by its flexibility, non-toxicity and biological compatibility to cell attachment. It has been fabricated using a UV lithographic technique. The irradiation dish forms a 2 2 mm 2 grid which contains 400 squares. Each square has 80 ?m side and is separated from neighbouring ones by 20 ?m wide walls. The location of each square is marked by a row letter and column number patterned outside the grid. The Cell Irradiation Facility at the Lund Nuclear Probe utilizes protons to irradiate living cells. A post-cell detection set up is used to control the applied dose, detecting the number of protons after passing through the targeted cell. The transmission requirement is fulfilled by our new irradiation dish. So far, the dish has been used to perform non-targeted irradiation of Hepatoma cells. The cells attach and grow easily on the SU-8 surface. In addition, the irradiation procedure can be performed routinely and faster since the cells are incubated and irradiated in the same surface.

Arteaga-Marrero, N.; Auzelyte, V.; Olsson, M. G.; Pallon, J.

2007-10-01

129

Updates to ISO 21348 (determining solar irradiances)  

NASA Astrophysics Data System (ADS)

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.

Tobiska, W. Kent

2012-07-01

130

Hepatobiliary Kinetics After Whole Body Irradiation.  

National Technical Information Service (NTIS)

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 mC...

A. Durakovic

1986-01-01

131

Aromatic nucleophilic substitutions under microwave irradiation  

Microsoft Academic Search

In order to study the effect of microwave irradiation over aromatic nucleophilic substitutions at atmospheric pressure and in a homogeneous medium, experiments with disubstituted-benzenes and the nucleophiles piperidine and potassium t-butoxide, in refluxing DMSO or DMF, were carried out. The aromatic nucleophilic substitutions under microwave irradiation were 2.7 to 12 times faster than under conventional reflux.

Gean V. Salmoria; Evandro Dall'Oglio; Csar Zucco

1998-01-01

132

Toxicity of irradiated media for Xenorhabdus spp  

Microsoft Academic Search

Bacterial isolates of the genus Xenorhabdus were shown to be extremely sensitive to photoproducts produced in a number of common media irradiated by fluorescent light. Two forms of toxic oxygen, hydrogen peroxide and superoxide radical, were produced in the media upon exposure to fluorescent light. The addition of pyruvate or catalase to the irradiated media eliminated the toxicity. The poor

J. Xu; R. E. Hurlbert

1990-01-01

133

Effects of mediastinal irradiation on oesophageal function.  

PubMed Central

Although it is well recognised that oesophageal symptoms are common during therapeutic mediastinal irradiation of intrathoracic malignant diseases, the effects of mediastinal irradiation on oesophageal function are poorly defined. To clarify the pathogenesis of these sequelae a prospective study was performed to document comprehensively the effects of mediastinal irradiation on oesophageal function. Oesophageal symptoms, barium swallow, endoscopy, and combined radionuclide scintigraphy and oesophageal manometry were evaluated in eight patients with potentially curable intrathoracic malignant disease before treatment, during the last week of mediastinal irradiation, and six to eight weeks after its completion. Before irradiation, structural abnormalities were excluded by barium swallow and endoscopy. All but one patient experienced odynophagia or dysphagia, or both, during mediastinal irradiation (p < 0.001) but endoscopic abnormalities were observed in only three patients and there was no correlation between oesophageal symptoms and endoscopic changes. Irradiation, however, had no significant effect on oesophageal motility or transit. It is concluded that oesophageal symptoms which develop during mediastinal irradiation are not a result of altered oesophageal motility or transit and may reflect increased mucosal sensitivity. PMID:8801191

Yeoh, E; Holloway, R H; Russo, A; Tippett, M; Bermingham, H; Chatterton, B; Horowitz, M

1996-01-01

134

Cherry Irradiation Studies. 1984 annual report  

SciTech Connect

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.

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

135

Solar irradiance variations due to active regions  

Microsoft Academic Search

Questions regarding changes in solar irradiance due to activity are important, since such changes may have a significant effect on the earth's climate. Solar irradiance measurements conducted outside the earth's atmosphere and, therefore, not affected by it have become possible by utilizing for such measurements satellites, such as the Nimbus 7 and the Solar Maximum Mission satellite (ACRIM experiment). The

L. Oster; K. H. Schatten; S. Sofia

1982-01-01

136

The solar spectral irradiance since 1700  

Microsoft Academic Search

The change in the irradiance spectrum of the Sun from 1700 to the last solar minimum is determined and compared to the change in the spectrum between activity minimum and maximum. For this purpose we have used detailed model flux spectra of solar magnetic features. Also, time-series of the solar spectral irradiance since 1700 in different wavelength bands are reconstructed.

M. Fligge; S. K. Solanki

2000-01-01

137

Total Solar Irradiance Satellite Composites and their  

E-print Network

Chapter 12 Total Solar Irradiance Satellite Composites and their Phenomenological Effect on Climate Nicola Scafetta Active Cavity Radiometer Irradiance Monitor (ACRIM) Lab, Coronado, CA 92118, USA, Duke. Phenomenological solar signature on climate 310 9. Conclusion 312 1. INTRODUCTION A contiguoustotal solar

Scafetta, Nicola

138

Thematic Mapper bandpass solar exoatmospheric irradiances  

Microsoft Academic Search

Based on solar irradiance data published by Neckel and Labs (1984) and Iqbal (1983), the solar exoatmospheric irradiances for Thematic Mapper (TM) bands 1, 2, 3 and 4 have been calculated. Results vary by up to 1 per cent from our previously published values which were based on earlier data of Neckel and Labs. For TM bands 5 and 7,

B. L. MARKHAM; J. L. BARKER

1987-01-01

139

Solar ultraviolet irradiance variations - A review  

Microsoft Academic Search

The absolute solar UV spectrum and the magnitude and structure of its temporal variations are examined. Solar magnetic activity and UV irradiance variations over the time scales of the evolution and rotation of solar active regions and over the 11-year solar cycle are studied and described. Data on EUV, Lyman-alpha, far UV, and middle UV irradiances are analyzed. Problems in

Judith Lean

1987-01-01

140

The LASP Interactive Solar IRradiance Datacenter (LISIRD)  

Microsoft Academic Search

LASP has created an online resource for combined solar irradiance datasets from the SORCE, TIMED, UARS, and SME missions. The LASP Interactive Solar IRradiance Datacenter (LISIRD) not only provides unified access to the individual datasets, but also combines them for ease of use by scientists, educators, and the general public. In particular, LISIRD makes available composite spectra and time series.

M. Snow; T. N. Woods; F. G. Eparvier; J. Fontenla; J. Harder; W. E. McClintock; C. Pankratz; E. Richard; A. Windnagel; D. Woodraska

2005-01-01

141

Dissolution of Olivine Promoted by Ion Irradiation  

NASA Astrophysics Data System (ADS)

Recent laboratory simulations of ion irradiation effects on planetary minerals show changes in the surface composition of surfaces that are different depending on whether the analysis is done in-situ (without removing the sample from vacuum) or ex-situ using an electron microscope. We found that olivine samples that have been irradiated by keV ions show preferential loss of magnesium when exposed to water. Irradiations were done with 4 keV argon ions to fluences between 1015 and 1018 ions/cm2. Soak times in high purity water ranged from minutes to days, and exhibit the same degree of Mg depletion, independent of soak time. The concentration of magnesium on the surface of irradiated natural olivine decreases by 40% upon contact with water, as measured with x-ray photoelectron spectroscopy. This finding is important for laboratory simulations of regolith processes and for establishing procedures for the handling of irradiated samples, including those from sample return missions.

Cantando, E. D.; Dukes, C. A.; Baragiola, R. A.

2006-12-01

142

Tensile properties of irradiated surveillance coupons  

SciTech Connect

Tensile testing of austenitic steel and superalloy samples irradiated in the HMO 13 assembly was performed in support of the Fast Flux Test Facility (FFTF) Surveillance Program. Postirradiation yield stress, ultimate tensile stress, uniform elongation, total elongation, and reduction in area of 304 stainless steel (SS), 308 SS weld, 316 SS, A286, In718, and In718 weld were determined. Results showed the strength of austenitic steels increased while the ductility decreased as a result of irradiation. Low irradiation exposure produced little property change in In718. Overall, the tensile properties of HMO 13 surveillance coupons showed a lower magnitude of irradiation-induced property change than was expected based on earlier studies. Results from these tests gave no indications of unexpectedly severe irradiation damage to FFTF components.

Huang, F.H.; Blackburn, L.D.

1994-06-01

143

AGC-1 Irradiation Experiment Test Plan  

SciTech Connect

The Advanced Graphite Capsule (AGC) irradiation test program supports the acquisition of irradiated graphite performance data to assist in the selection of the technology to be used for the VHTR. Six irradiations are planned to investigate compressive creep in graphite subjected to a neutron field and obtain irradiated mechanical properties of vibrationally molded, extruded, and iso-molded graphites for comparison. The experiments will be conducted at three temperatures: 600, 900, and 1200C. At each temperature, two different capsules will be irradiated to different fluence levels, the first from 0.5 to 4 dpa and the second from 4 to 7 dpa. AGC-1 is the first of the six capsules designed for ATR and will focus on the prismatic fluence range.

R. L. Bratton

2006-05-01

144

Significance of primary irradiation creep in graphite  

NASA Astrophysics Data System (ADS)

Traditionally primary irradiation creep is introduced into graphite analysis by applying the appropriate amount of creep strain to the model at the initial time-step. This is valid for graphite components that are subjected to high fast neutron flux fields and constant stress fields, but it does not allow for the effect of movement of stress locations around a graphite component during life, nor does it allow primary creep to be applied rate-dependently to graphite components subject to lower fast neutron flux. This paper shows that a differential form of primary irradiation creep in graphite combined with the secondary creep formulation proposed by Kennedy et al. performs well when predicting creep behaviour in experimental samples. The significance of primary irradiation creep in particular in regions with lower flux is investigated. It is shown that in low flux regions with a realistic operating lifetime primary irradiation creep is significant and is larger than secondary irradiation creep.

Erasmus, Christiaan; Kok, Schalk; Hindley, Michael P.

2013-05-01

145

Decontamination of pancreatin powder by gamma irradiation  

NASA Astrophysics Data System (ADS)

Dehydrated pancreatin, packed in polyethylene bags, was gamma irradiated with doses of 5, 10, 15 and 20 kGy. Control and irradiated samples were stored at 19 4 C and 70 10% RH during 14 months. Microbiological and chemical tests were performed. Samples irradiated with 5 kGy showed two log cycles reduction of sporulated and aerobic mesophilic bacteria, and one log cycle reduction of moulds and yeasts, which fulfilled the microbiological requirements. This situation was maintained throughout the storage period. The irradiation did not significantly affect water content, fat, and total volatile basic nitrogen. Protease and amylase activities decreased with storage time and radiation dose. However, irradiation with 5 and 10 kGy caused no significant alteration on either of these activities as compared with control samples.

Kairiyama, Eulogia; Narvaiz, Patricia

1997-03-01

146

AFIP-1 Irradiation Summary Report  

SciTech Connect

The Advanced Test Reactor (ATR) Full size plate In center flux trap Position (AFIP) experiment AFIP-1 was designed to demonstrate the performance of second-generation dispersion fuels at a prototypic scale with a length of 21.5 inches (54.6 cm), width of 2.25 inches (5.75 cm) and a thickness of 0.050 inch (0.13 cm). The experiment was fabricated using commercially standard practices at BWX Technology, Inc. (BWXT). The U-7Mo fuel particles were supplied by the Korean Atomic Energy Research Institute (KAERI) using equipment intended for commercial supply. Two fuel plates were tested that incorporated two different matrix compositions, Al-2Si and Al-4043.1 The following report summarizes the life of the AFIP-1 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

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

2011-05-01

147

Irradiation performance of metallic fuels  

SciTech Connect

Argonne National Laboratory has been working for the past 5 yr to develop and demonstrate the Integral Fast Reactor concept. The concept involves a closed system for fast reactor power generation and on-site fuel reprocessing, both designed specifically around the use of metallic fuel. The Experimental Breeder Reactor II has used metallic fuel for all of its 25-yr life. In 1985, tests were begun to examine the irradiation performance of advanced-design metallic fuel systems based on U-Zr or U-Pu-Zr fuels. These test have demonstrated the viable performance of these fuel systems to high burnup. The initial testing program is described in this paper. The performance data base to date has shown that metallic fuel systems can perform reliably to high burnups over a wide range of design conditions. The data base is continually being strengthened to support performance modeling efforts and development of advanced reactor systems such as General Electric Company's PRISM.

Pahl, R.G.; Lahm, C.E.; Porter, D.L.; Batte, G.L. (Argonne National Lab., Idaho Falls, ID (USA)); Hofman, G.L. (Argonne National Lab., IL (USA))

1989-01-01

148

[Irradiation in stereotactic conditions: Prerequisites].  

PubMed

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

Maingon, P; Lisbona, A

2014-10-01

149

RERTR-10 Irradiation Summary Report  

SciTech Connect

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.

D. M. Perez

2011-05-01

150

AFIP-2 Irradiation Summary Report  

SciTech Connect

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.

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

2011-05-01

151

AFIP-2 Irradiation Summary Report  

SciTech Connect

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.

Danielle M Perez

2011-04-01

152

Solar Irradiance Variability and Climate  

E-print Network

The brightness of the Sun varies on all time scales on which it has been observed, and there is increasing evidence that it has an influence on climate. The amplitudes of such variations depend on the wavelength and possibly on the time scale. Although many aspects of this variability are well established, the exact magnitude of secular variations (going beyond a solar cycle) and the spectral dependence of variations are under discussion. The main drivers of solar variability are thought to be magnetic features at the solar surface. The climate reponse can be, on a global scale, largely accounted for by simple energetic considerations, but understanding the regional climate effects is more difficult. Promising mechanisms for such a driving have been identified, including through the influence of UV irradiance on the stratosphere and dynamical coupling to the surface. Here we provide an overview of the current state of our knowledge, as well as of the main open questions.

Solanki, S K; Haigh, J D

2013-01-01

153

Endonucleolytic incision of UVB-irradiated DNA  

SciTech Connect

Ultraviolet irradiation of DNA produces a variety of pyrimidine damages. In addition to the well-known photoproducts, pyrimidine dimers and 6-4'-(pyrimidin-2'one)pyrimidines, DNA sequence analysis has shown that purified E. coli endonuclease III incises broad-spectrum UV-irradiated DNA at cytosines and OsO/sub 4/-oxidized DNA at thymines. The wavelength dependence of endonuclease III incision of superhelical DNA irradiated by 250 to 320 nm. monochromatic light was examined. Maximal enzymic cleavage was obtained with substrates irradiated between 265 and 285 nm, with peak activity at 280 nm. Incision of DNA irradiated at 254 nm was reduced. Therefore, these cytosine photoproducts are optimally formed at biologically significant wavelengths and may be involved in actinic carcinogenesis. Enzymic release of modified labeled cytosine into the ethanol-soluble fraction from irradiated poly(dG-dC):poly(dG-dC) was linear with time of reaction, quantity of enzyme protein and exposure of substrate to irradiation. Identification of the cytosine UV photoproduct is currently under investigation.

Weiss, R.B.; Duker, N.J.

1987-05-01

154

Microstructural modifications in swift ion irradiated PET  

NASA Astrophysics Data System (ADS)

Polyethylene terephthalte (PET) was irradiated with carbon (70 MeV) and copper (120 MeV) ions to analyze the induced modifications with respect to optical, structural and thermal properties. In the present investigation, the fluence for carbon irradiation was varied from 110 11 to 110 14 ions cm -2, while that for copper beam was kept in the range of 110 11 to 110 13 ions cm -2. UV-vis, FTIR, XRD and DSC techniques were utilized to study the induced changes. The analysis of UV-vis absorption studies reveals that there is decrease of optical energy gap up to 10% on carbon ion irradiation (at 110 14 ions cm -2), whereas the copper beam (at 110 13 ions cm -2) leads to a decrease of 49%. FTIR analysis indicated the formation of alkyne end groups along with the overall degradation of polymer with copper ion irradiation. X-ray diffraction analysis revealed that the semi-crystalline PET losses its crystallinity on swift ion irradiation. It was found that the carbon beam (110 14 ions cm -2) decreased the crystallite size by 16% whereas this decrease is of 12% in case of the copper ion irradiated PET at 110 13 ions cm -2. The loss in crystallinity on irradiation has been supported by DSC thermograms.

Singh, Ravinder; Singh Samra, Kawaljeet; Kumar, Ramneek; Singh, Lakhwant

2008-05-01

155

Rapid detection of irradiated frozen hamburgers  

NASA Astrophysics Data System (ADS)

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.

Delince, Henry

2002-03-01

156

AGR-1 Irradiation Experiment Test Plan  

SciTech Connect

This document presents the current state of planning for the AGR-1 irradiation experiment, the first of eight planned irradiations for the Advanced Gas Reactor (AGR) Fuel Development and Qualification Program. The objectives of the AGR-1 experiment are: 1. To gain experience with multi-capsule test train design, fabrication, and operation with the intent to reduce the probability of capsule or test train failure in subsequent irradiation tests. 2. To irradiate fuel produced in conjunction with the AGR fuel process development effort. 3. To provide data that will support the development of an understanding of the relationship between fuel fabrication processes, fuel product properties, and irradiation performance. In order to achieve the test objectives, the AGR-1 experiment will be irradiated in the B-10 position of the Advanced Test Reactor (ATR) at the Idaho National Laboratory (INL). The test will contain six independently controlled and monitored capsules. Each capsule will contain a single type, or variant, of the AGR coated fuel. The irradiation is planned for about 700 effective full power days (approximately 2.4 calendar years) with a time-averaged, volume-average temperature of approximately 1050 C. Average fuel burnup, for the entire test, will be greater than 17.7 % FIMA, and the fuel will experience fast neutron fluences between 2.4 and 4.5 x 1025 n/m2 (E>0.18 MeV).

John T. Maki

2009-10-01

157

Neutron irradiation creep in stainless steel alloys  

NASA Astrophysics Data System (ADS)

Irradiation creep elongations were measured in the HFR at Petten on AMCR steels, on 316 CE-reference steels, and on US-316 and US-PCA steels varying the irradiation temperature between 300C and 500C and the stress between 25 and 300 MPa. At the beginning of an irradiation a type of "primary" creep stage is observed for doses up to 3-5 dpa after which dose the "secondary" creep stage begins. The "primary" creep strain decreases in cold-worked steel materials with decreasing stress and decreasing irradiation temperature achieving also negative creep strains depending also on the pre-treatment of the materials. These "primary" creep strains are mainly attributed to volume changes due to the formation of radiation-induced phases, e.g. to the formation of ?-ferrite below about 400C and of carbides below about 700C, and not to irradiation creep. The "secondary" creep stage is found for doses larger than 3 to 5 dpa and is attributed mainly to irradiation creep. The irradiation creep rate is almost independent of the irradiation temperature ( Qirr = 0.132 eV) and linearly dependent on the stress. The total creep elongations normalized to about 8 dpa are equal for almost every type of steel irradiated in the HFR at Petten or in ORR or in EBR II. The negative creep elongations are more pronounced in PCA- and in AMCR-steels and for this reason the total creep elongation is slightly smaller at 8 dpa for these two steels than for the other steels.

Schle, Wolfgang; Hausen, Hermann

1994-09-01

158

Green coffee decontamination by electron beam irradiation  

NASA Astrophysics Data System (ADS)

Microbiological load of green coffee is a real problem considering that it is extremely sensitive to contamination. Irradiation is a decontamination method for a lot of foodstuffs, being a feasible, very effective and environment friendly one. Beans and ground green coffee were irradiated with electron beams up to 40 kGy. Microbial load, rheological behavior, electron paramagnetic resonance (EPR) and visible spectroscopy were carried out. The results show that electron beam irradiation of green coffee could decontaminate it without severe changes in its properties.

Nemtanu, Monica R.; Brasoveanu, Mirela; Grecu, Maria Nicoleta; Minea, R.

2005-10-01

159

Lymphocyte pyknosis following cobalt - 60 gamma irradiation  

E-print Network

groups of six rats each were irradiated with the fir st, group receiving 200 rads and the second, 800 rads. Control animals (6 per group) were mock irradiated. Immediately tail clips were done on all animals. A white blood cell count and a... flushed with the gas mixture and sealed. The third experiment employed methods utilized in experiments I and II. Five animals were irradiated at each dose level: 200 rads and 800 rads. Five controls were employed with each group. Animal one in each...

Lane, Linda Kay

2012-06-07

160

Total body calcium analysis. [neutron irradiation  

NASA Technical Reports Server (NTRS)

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.

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

1974-01-01

161

Solar Cycle Variation in Solar Irradiance  

NASA Astrophysics Data System (ADS)

The correlation between solar irradiance and the 11-year solar activity cycle is evident in the body of measurements made from space, which extend over the past four decades. Models relating variation in solar irradiance to photospheric magnetism have made significant progress in explaining most of the apparent trends in these observations. There are, however, persistent discrepancies between different measurements and models in terms of the absolute radiometry, secular variation and the spectral dependence of the solar cycle variability. We present an overview of solar irradiance measurements and models, and discuss the key challenges in reconciling the divergence between the two.

Yeo, K. L.; Krivova, N. A.; Solanki, S. K.

2014-07-01

162

Solar cycle variation in solar irradiance  

E-print Network

The correlation between solar irradiance and the 11-year solar activity cycle is evident in the body of measurements made from space, which extend over the past four decades. Models relating variation in solar irradiance to photospheric magnetism have made significant progress in explaining most of the apparent trends in these observations. There are, however, persistent discrepancies between different measurements and models in terms of the absolute radiometry, secular variation and the spectral dependence of the solar cycle variability. We present an overview of solar irradiance measurements and models, and discuss the key challenges in reconciling the divergence between the two.

Yeo, K L; Solanki, S K

2014-01-01

163

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

NASA Technical Reports Server (NTRS)

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.

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

164

Bystander responses in low dose irradiated cells treated with plasma from gamma irradiated blood  

Microsoft Academic Search

There are two specific low-dose radiation-induced responses that have been the focus of radiobiologists' interest in recent years. These are the bystander effect in non-irradiated cells and the adaptive response to a challenge dose after prior low dose irradiation. In the present study we have investigated if plasma from irradiated blood can act as a 'challenge dose' on low dose

A. Acheva; R. Georgieva; I. Rupova; R. Boteva; F. Lyng

2008-01-01

165

Selective irradiation of the vascular endothelium  

E-print Network

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 ...

Schuller, Bradley W

2007-01-01

166

10 CFR 36.33 - Irradiator pools.  

...a) For licenses initially issued after July 1, 1993, irradiator pools must either: (1) Have a water-tight stainless steel liner or a liner metallurgically compatible with other components in the pool; or (2) Be constructed...

2014-01-01

167

Total lymphoid irradiation in alloimmunity and autoimmunity  

SciTech Connect

Total lymphoid irradiation has been used as an immunosuppressive regimen in autoimmune disease and organ transplantation. The rationale for its use originated from studies of patients with Hodgkin disease, in whom this radiotherapy regimen was noted to induce profound and long-lasting immune suppression and yet was well tolerated, with few long-term side effects. Total lymphoid irradiation is a unique immunosuppressive regimen that produces a selective (and long-lasting) reduction in the number and function of helper T cells and certain subsets of B cells. Conventional immunosuppressive drugs show little selectivity, and their effects are short-lived. The most important aspect of total lymphoid irradiation is the potential for achieving transplantation tolerance and permanent remissions in autoimmune disease in laboratory animals. Attempts are being made to achieve similar goals in humans given total lymphoid irradiation, so that immunosuppressive drugs can be ultimately withdrawn from transplant recipients and patients with lupus nephritis. 28 references.

Strober, S.

1987-12-01

168

The Solar EUV Irradiance: New Insights  

NASA Astrophysics Data System (ADS)

A key to understanding variability in the Earth's atmosphere is understanding the variability in the solar irradiance that is a primary source of energy into the Earth system. Variations in this input drive variability in different atmospheric regions depending on where solar photons of particular wavelengths are absorbed. Of particular interest to the TIGER community is the solar extreme ultraviolet (EUV) irradiance that creates the ionosphere and heats the thermosphere. The ten-year record of solar spectral irradiance in the extreme ultraviolet (EUV) from Solar EUV Experiment (SEE) on NASA's Thermosphere Ionosphere Mesosphere Energetics and Dynamics (TIMED) mission, now continued at higher spectral and temporal resolution by the EUV Variability Experiment (EVE) on NASA's Solar Dynamics Observatory (SDO) provide us with an excellent set of well-calibrated data with which to study the variability of the important solar EUV spectral irradiance on timescales of the solar cycle, solar rotation, and now flares, and how it impacts the Earth's atmospheric variability.

Eparvier, Francis

2012-07-01

169

Degradation pathways of PCB upon gamma irradiation  

SciTech Connect

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.

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

1990-11-01

170

UV microspot irradiator at Columbia University.  

PubMed

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

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

2013-08-01

171

Correlations of solar cycle 22 UV irradiance  

NASA Technical Reports Server (NTRS)

The solar ultraviolet spectral irradiance monitor (SUSIM) onboard the upper atmosphere research satellite (UARS) is an absolutely calibrated UV spectrometer which has measured the solar spectral irradiance over the wavelengths 115 nm to 410 nm since October 1991. This data set now extends for about six years from near the peak of solar cycle 22, through its minimum, to the initial rise associated with solar cycle 23. Generally, the time series of UV spectral irradiances obtained shows behavior similar to that of other solar activity indices. The conditions on the sun, which can in result in dominant 13.5-day periodicity, are analyzed and illustrated. It is found that any combination of presence or absence of dominant 13.5-day in UV irradiance and solar wind velocity is possible depending entirely on the particular surface distribution and orientation of solar active regions.

Floyd, L.; Brueckner, G.; Crane, P.; Prinz, D.; Herring, L.

1997-01-01

172

He-Ne laser extravascular irradiation therapy  

NASA Astrophysics Data System (ADS)

Based on the study of tissue optics related with the laser irradiation blood therapy, a new treatment method, extravascular low-level laser irradiation therapy (ELLLI) is developed. The veins of 30 patients with cerebrovascular disease combined with diabetes, asthma were treated by He-Ne laser (632.8nm, 25mW) which was delivered by an optics fiber. The fiber was outside the patient's skin and the laser irradiated on the blood vessel perpendicularly. The therapy time was 60 minutes each time and about 7-10 times a course of the treatment. The values of blood sugar, blood- fat and hemorrheology were measured as the effective indexes. After the treatment the effective indexes and the symptoms of the patients were all improved. With the advantages of simplicity and safety (no medical infection), laser extravascular irradiation therapy is likely to be a new medical method for heart brain and other diseases.

Chen, Rong; Chen, Huifang; Xie, Shusen; Chen, Yanjiao; Zhang, Yanrong

2000-10-01

173

UV Microspot Irradiator at Columbia University  

PubMed Central

The Radiological Research Accelerator Facility (RARAF) 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 microspots 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 the live zebrafish embryo. PMID:23708525

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

2013-01-01

174

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...

175

Downscaling of global solar irradiation in R  

E-print Network

A methodology for downscaling solar irradiation from satellite-derived databases is described using R software. Different packages such as raster, parallel, solaR, gstat, sp and rasterVis are considered in this study for improving solar resource estimation in areas with complex topography, in which downscaling is a very useful tool for reducing inherent deviations in satellite-derived irradiation databases, which lack of high global spatial resolution. A topographical analysis of horizon blocking and sky-view is developed with a digital elevation model to determine what fraction of hourly solar irradiation reaches the Earth's surface. Eventually, kriging with external drift is applied for a better estimation of solar irradiation throughout the region analyzed. This methodology has been implemented as an example within the region of La Rioja in northern Spain, and the mean absolute error found is a striking 25.5% lower than with the original database.

Antonanzas-Torres, F; Antonanzas, J; Perpin, O

2013-01-01

176

Electron beam irradiation for structuring of molecular assemblies  

Microsoft Academic Search

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

Victor Erokhin; Tatiana Berzina; M. P. Fontana

2004-01-01

177

A review of the safety of cold pasteurization through irradiation  

Microsoft Academic Search

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

Lester M. Crawford; Eric H. Ruff

1996-01-01

178

ACCEPTANCE OF IRRADIATED BEEF AND ITS EFFECT ON BEEF CONSUMPTION  

Microsoft Academic Search

There is a growing body of scientific evidence at - testing to the effectiveness of irradiation in killing harmful substances such as parasites and bacteria in food. Hence, food irradiation can enhance the safety level of food. Furthermore, if conducted properly, irradiation does not adversely affect the nutritional quality of food. The benefits of food irradiation are well recognized and

Senhui He; Stanley M. Fletcher; Arbindra Rimal

2004-01-01

179

DISCREPANCY IN AEROSOL FORCING OF DIFFUSE DOWNWELLING SHORTWAVE IRRADIANCE  

E-print Network

components Direct Normal Solar Irradiance DNSI Diffuse Downwelling Irradiance DDI SHADED PYRANOMETER #12;DNSI CLOSURE EXPERIMENT Direct Normal Solar Irradiance (DNSI): Measure: Normal incidence pyrheliometer, Active cavity radiometer Model: DNSI = - E d0( )exp( ) E0( ) = solar spectral irradiance at top of atmosphere

Schwartz, Stephen E.

180

Sources of Solar Total Irradiance Variations  

NASA Astrophysics Data System (ADS)

The daily images and magnetograms acquired by MDI are a rich source of information about the contributions of different types of solar regions to variations in the total solar irradiance (TSI). These data have been used to determine the temporal variation of the MDI irradiance, the mean intensity of the solar disk in the continuum at 676.8 nm. The short-term (days to weeks) variations of the MDI irradiance and TSI are in excellent agreement with rms differences of 0.011%. This indicates that MDI irradiance is an excellent proxy for short-term variations of TSI from the competing irradiance contributions of regions causing irradiance increases, such as plages and bright network, and regions causing irradiance decreases, such as sunspots. However, the long-term or solar cycle variation of the MDI proxy and TSI differ over the 11-year period studied. The results indicate that the primary sources of the long-term (several months or more) variations in TSI are regions with magnetic fields between about 80 and 600 G. The results also suggest that the difference in the long-term variations of the MDI proxy and TSI is due to a component of TSI associated with sectors of the solar spectrum where the contrast in intensity between plages and the quiet Sun is enhanced ( e.g., the UV) compared to the MDI proxy. This is evidence that the long-term variation of TSI is due primarily to solar cycle variations of the irradiance from these portions of solar spectrum, a finding consistent with modeling calculations indicating that approximately 60% of the change in TSI between solar minimum and maximum is produced by the UV part of the spectrum shortward of 400 nm (Solanki and Krivova, Space Sci. Rev. 125, 53, 2006).

Withbroe, George L.

2009-06-01

181

An introduction to gamma irradiation center  

NASA Astrophysics Data System (ADS)

Radiation processing status in the Islamic Republic of Iran is reviewed. Gamma Irradiation Center is the only center offering irradiation services to the manufacturers of disposable medical and hygienic supplies in the country. As a promoter of this technology GIC has also assumed a role and developed capacities for quality control, research and development in this expanding field of endeavor. The personnel, physical facilities, operations record, quality control, and research activities of the GIC is presented.

Sohrabpour, M.

182

FTIR analysis of microwave irradiated polymer nanocomposites  

NASA Astrophysics Data System (ADS)

Polymer nanocomposites were prepared in the form of thin films of 30?m by using solution cast method. The samples were prepared with silver nanoparticles and TiO2 nanopowder and dispersed in polycarbonate. These composite polymer films were irradiated by various doses of microwaves at 100 to 750 W for 10 minutes in commercial microwave oven. The FTIR spectra were taken for various samples and compared. The results show the effect of microwave irradiation on polymer nanocomposites.

Acharya, N. K.; Prajapati, A. N.

2010-06-01

183

Effects of ion irradiation in metallic glasses  

Microsoft Academic Search

Application of metallic glasses as structural materials has been limited by their poor ductility. To overcome brittle failure, nanocrystals are intentionally introduced to stabilize the glasses. In this study, we report on the application of ion irradiation to induce nanocrystalization in a Cu50Zr45Ti5 (CZT) alloy. Transmission electron microcopy, microindentation and nanoindentation have been used to characterize the CZT alloy irradiated

Jesse Carter; E. G. Fu; G. Bassiri; B. M. Dvorak; N. David Theodore; Guoqiang Xie; D. A. Lucca; Michael Martin; Mark Hollander; Xinghang Zhang; Lin Shao

2009-01-01

184

Neutron Irradiation Resistance of RAFM Steels  

SciTech Connect

The neutron irradiation resistance of the reduced-activation ferritic/martensitic (RAFM) steel EUROFER97 and international reference steels (F82H-mod, OPTIFER-Ia, GA3X and MANET-I) have been investigated after irradiation in the Petten High Flux Reactor up to 16.3 dpa at different irradiation temperatures (250-450 deg. C). The embrittlement behavior and hardening are investigated by instrumented Charpy-V tests with sub-size specimens. Neutron irradiation-induced embrittlement and hardening of EUROFER97 was studied under different heat treatment conditions. Embrittlement and hardening of as-delivered EUROFER97 steel are comparable to those of reference steels. Heat treatment of EUROFER97 at a higher austenitizing temperature substantially improves the embrittlement behaviour at low irradiation temperatures. Analysis of embrittlement vs. hardening behavior of RAFM steels within a proper model in terms of the parameter C={delta}DBTT/{delta}{sigma} indicates hardening-dominated embrittlement at irradiation temperatures below 350 deg. C with 0.17 {<=} C {<=} 0.53 deg. C/MPa. Scattering of C at irradiation temperatures above 400 deg. C indicates non hardening embrittlement. A role of He in a process of embrittlement is investigated in EUROFER97 based steels, that are doped with different contents of natural B and the separated {sup 10}B-isotope (0.008-0.112 wt.%). Testing on small scale fracture mechanical specimens for determination of quasi-static fracture toughness will be also presented in a view of future irradiation campaigns. (authors)

Gaganidze, Ermile; Dafferner, Bernhard; Aktaa, Jarir [Institute for Materials Research II, Forschungszentrum Karlsruhe GmbH, Eggenstein-Leopoldshafen (Germany)

2008-07-01

185

Polarizations in Irradiated Proton and Deuterated Materials  

NASA Astrophysics Data System (ADS)

Polarizations from a series of irradiations of deuterated and hydrogenous materials are presented. Irradiated deuterated butanol has the best performance with polarizations of 50.5% and -47.6% at 5.0 T, rising to 62.4% and -49.6% at 6.55 T. Deuterated 1-pentanol has a similar performance at 5 T. The results from hydrogenated materials are not as promising, giving values considerably less than obtained with standard chemical doping.

Crabb, D. G.

2007-04-01

186

10 CFR 36.33 - Irradiator pools.  

Code of Federal Regulations, 2010 CFR

...and that could act as siphons must have siphon breakers to prevent the siphoning of pool water. (c) A means must be provided...around or over irradiator pools during normal operation to prevent personnel from accidentally falling into the pool. The barrier...tools or poles are used in irradiator pools, the radiation dose rate on the handling areas of the tools may not......

2010-01-01

187

Neutron irradiation induced amorphization of silicon carbide  

Microsoft Academic Search

This paper provides the properties of bulk stoichiometric silicon carbide which has been amorphized under neutron irradiation. Both high purity single crystal hcp and high purity, highly faulted (cubic) chemically vapor deposited (CVD) SiC were irradiated at approximately 60C to a total fast neutron fluence of 2.61025 n\\/m2. Amorphization was seen in both materials as evidenced by TEM, electron diffraction

L. L Snead; J. C Hay

1999-01-01

188

NUCLEAR IRRADIATION EFFECTS ON FERROMAGNETIC CORE MATERIALS  

Microsoft Academic Search

Effects of nuclear irradiation on the magnetic properties of 14 ; representative core materials were investigated. Measurements before, during, ; and after irradiation were made at a flux level of about 10¹² neutrons\\/ cm\\/; sup 2\\/ sec and for a total integrated neutron flux of ~ 10¹⁸ nvt. The fast ; flux (E) 1 ev) was about 10¹¹ n\\/cm² sec

R. S. Sery; D. I. Gordon

1958-01-01

189

Hyperparathyroidism After Irradiation for Childhood Malignancy  

Microsoft Academic Search

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

Todd McMullen; Greg Bodie; Anthony Gill; Catharina Ihre-Lundgren; Albert Shun; Mary Bergin; Graham Stevens; Leigh Delbridge

2009-01-01

190

COBALT60 Gamma Irradiation of Shrimp  

Microsoft Academic Search

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

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

1993-01-01

191

Evaluation of irradiation effects on concrete structure  

SciTech Connect

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)

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

192

Total lymphoid irradiation and discordant cardiac xenografts  

SciTech Connect

Total lymphoid irradiation can prolong concordant cardiac xenografts. The effects of total lymphoid irradiation in a discordant xenograft model (guinea pig to rat) were studied with and without adjuvant pharmacologic immunosuppression. Inbred Lewis rats were randomly allocated to one of four groups. Group 1 (n = 6) served as a control group and rats received no immunosuppression. Group 2 (n = 5) received triple-drug therapy that consisted of intraperitoneal azathioprine (2 mg/kg), cyclosporine (20 mg/kg), and methylprednisolone (1 mg/kg) for 1 week before transplantation. Group 3 animals (n = 5) received 15 Gy of total lymphoid irradiation in 12 divided doses over a 3-week period. Group 4 (n = 6) received both triple-drug therapy and total lymphoid irradiation as described for groups 2 and 3. Complement-dependent cytotoxicity assay was performed to determine if a correlation between complement-dependent cytotoxicity and rejection-free interval existed. Rejection was defined as cessation of graft pulsation and was confirmed by histologic test results. Only groups 1 and 2 showed a difference in survival (group 1, 6.9 +/- 1.0 minutes; group 2, 14.2 +/- 2.7 minutes, p = 0.02). Although total lymphoid irradiation did decrease complement-dependent cytotoxicity, linear regression revealed no correlation between complement-dependent cytotoxicity and graft survival (coefficient of correlation, 0.30). Unlike concordant cardiac xenografts, total lymphoid irradiation with or without triple-drug therapy does not prolong graft survival.

Kaplan, E.; Dresdale, A.R.; Diehl, J.T.; Katzen, N.A.; Aronovitz, M.J.; Konstam, M.A.; Payne, D.D.; Cleveland, R.J. (Tufts Univ. School of Medicine, Boston, MA (USA))

1990-01-01

193

Irradiation of municipal sludge for agricultural use  

NASA Astrophysics Data System (ADS)

Research has demonstrated that irradiation is an effective means for reducing pathogens in sewage sludge to levels where sludge reuse in public areas meets criteria for protection of the public health. Complementary research has demonstrated the value of the irradiated sludge in both agronomic and animal science applications. The benefits of sludge application to cropland are well documented. The irradiation process does not increase the extractability and plant uptake of a broad range of nutrients and heavy metals from sludge-amended soils. However, it does eliminate the hazards associated with pathogen contamination when applying sludge to agricultural land. Irradiated sludge has also been evaluated as a supplemental foodstuff for cattle and sheep. The data indicate that products derived from raw sewage may have a substantial nutritive value for ruminant animals. Irradiation of sewage sludge is a practical means of sludge disinfection. Where a highly disinfected sludge is required, it should be considered as a viable sludge management alternative. Evaluation of sludge irradiation technology and its associated costs must be done with consideration of other sludge treatment processes to develop an acceptable sludge management system.

Ahlstrom, Scott B.

194

Time resolved observations of irradiated brown dwarfs  

NASA Astrophysics Data System (ADS)

Irradiation of substellar brown dwarfs and hot Jupiters in close binaries can increase their surface temperatures by an order of magnitude, alter their radii and atmospheric structure, and lead to moderate mass loss. In these tidally locked systems, temperature diffences between the 'day' and 'night' sides could lead to strong winds and jet streams transporting heat to the 'night' side. We have discovered two new close white dwarf+brown dwarf binaries. Optical photometry suggests that in both systems the brown dwarfs are being irradiated by their hotter white dwarf companions. We have obtained observations of a similar system, WD0137-349, and determined that the level of irradiation in the IRAC [4.5] micron band is 40% suggesting that the irradiation is significantly affecting the atmosphere. We will obtain time-resolved IRAC photometry for each both targets over an entire orbital period. We will use both IRAC bands for the brighter WD+L dwarf binary, and only [3.6] for the fainter target, which has a longer orbital period. We will use these data to make a detailed investigation of the heating effects on the brown dwarfs' atmosphere. These observations will help us to understand how irradiation affects the atmospheric structure and evolution of very cool, low mass objects, and to develop and test new atmospheric models for irradiated brown dwarfs and hot Jupiters.

Casewell, Sarah; Burleigh, Matt; Steele, Paul; Lawrie, Katherine

2012-12-01

195

Measurement and evaluation of the irradiation test parameters for a specimen in a HANARO material irradiation capsule  

Microsoft Academic Search

A material capsule system has been developed for irradiation tests of nuclear materials in the core region of the High-flux Advanced Neutron Application Reactor (HANARO) and has been actively utilized for the various material irradiation tests requested by numerous users. For an irradiation test in the reactor, nuclear characteristics and irradiation temperature of the capsule parts are basically necessary for

K. N. Choo; B. G. Kim; M. S. Cho; Y. K. Kim; J. J. Ha

2009-01-01

196

Measurement and Evaluation of the Irradiation Test Parameters for a Specimen in a HANARO Material Irradiation Capsule  

Microsoft Academic Search

A material capsule system has been developed for irradiation tests of nuclear materials in the core region of the high-flux advanced neutron application reactor (HANARO) and has been actively utilized for the various material irradiation tests requested by numerous users. For an irradiation test in the reactor, nuclear characteristics and irradiation temperature of the capsule parts are essential for the

K. N. Choo; B. G. Kim; M. S. Cho; Y. K. Kim; J. J. Ha

2010-01-01

197

On the distribution of irradiation intensity in phototherapy. Measurements of effective irradiance in an incubator  

Microsoft Academic Search

Knowledge of the effective irradiation dose is a prerequisite to predicting the efficacy of phototherapy. To gain this information, the field of irradiation of a phototherapy lamp was measured in an incubator. It became apparent that the radiant power is extremely heterogeneously distributed in the incubator. By decreasing the distance from the lamps, the radiant power is increased, with the

P. Eggert; C. Stick; H. Schrder

1984-01-01

198

Unwillingness to Consume Irradiated Beef and Unwillingness to Pay for Beef Irradiation  

Microsoft Academic Search

The benefi ts of food irradiation, such as effectively killing harmful microorganisms, prolonging shelf life of food, and reducing spoilage, have long been recognized by food-safety authorities. Application of food irradiation has been promoted at an inter- national level by the Food and Agricultural Orga- nization (FAO) and the World Health Organization (WHO) of the United Nations. In the United

Senhui He; Stanley M. Fletcher; Arbindra Rimal

2005-01-01

199

Short-term solar irradiance and irradiation forecasts via different time series techniques: A preliminary study  

E-print Network

This communication is devoted to solar irradiance and irradiation short-term forecasts, which are useful for electricity production. Several different time series approaches are employed. Our results and the corresponding numerical simulations show that techniques which do not need a large amount of historical data behave better than those which need them, especially when those data are quite noisy.

Join, Cdric; Fliess, Michel; Muselli, Marc; Nivet, Marie Laure; Paoli, Christophe; Chaxel, Frdric

2014-01-01

200

Embrittlernent of irradiated F82H in the absence of irradiation hardening  

SciTech Connect

Neutron irradiation of 7-12% Cr ferritic/martensitic steels below 425-450 C produces microstructural defects and precipitation that cause an increase in yield stress. This irradiation hardening causes embrittlement, which is observed in a Charpy impact or fracture toughness test as an increase in the ductile-brittle transition temperature. Based on observations that show little change in strength in steels irradiated above 425-450 C, the general conclusion has been that no embrittlement occurs above these temperatures. In a recent study of F82H steel, significant embrittlement was observed after irradiation at 500 C. This embrittlement is apparently due to irradiation-accelerated Laves-phase precipitation. Observations of the embrittlement in the absence of hardening has been examined and analyzed with thermal-aging studies and computational thermodynamics calculations to illuminate and understand the effect.

Klueh, Ronald L [ORNL; Shiba, Kiyoyuki [ORNL; Sokolov, Mikhail A [ORNL

2009-01-01

201

Comparison of irradiation hardening and microstructure evolution in ion-irradiated delta and epsilon hydrides  

NASA Astrophysics Data System (ADS)

A ?-Zr-hydride was irradiated with 6.4 MeV Fe3+ ions to clarify the relationship between hardening and microstructural changes of bulk Zr-hydrides under neutron irradiation. Irradiation hardening was measured by nanoindentation tests. Transmission electron microscope cross-sectional observations showed that the deformation mechanism of the ?-Zr-hydride was both slip and twinning. Dislocation loops were observed in the irradiated hydride matrix. These irradiation-induced defects make slip deformation difficult and consequently promote the twin deformation of ?-Zr-hydride. This work is a continuation of the previous our work (J. Nucl. Mater. 419 (2011) 366-370) focused upon ?-Zr-hydride and we discuss a comparison between the two Zr-hydrides. The deformation mechanism involves both slip and twinning. Cracks were formed in both the irradiated and unirradiated area. epsi;-phase (fct structure): Twinning is the dominant deformation mechanism. Some slip deformation was also observed. Cracks were formed at the Berkovich indentations in the irradiated area. Ion irradiation does not change the deformation mechanism in either phase, although twin deformation and crack formation were more frequently observed in the irradiated regions of ?-phase and ?-phase, respectively. The difference of the deformation mechanism between ?-phase and ?-phase can be explained by the difference in the stacking fault energy between the two phases. According to Udagawa et al. [26] the stacking fault energy in the Zr-hydride decreases with increasing the hydrogen content. This indicates that deformation may occur more easily in the ?-phase than in the ?-phase. For the ?-phase, the deformation mechanism is deduced to be the slip system of calcium fluoride, that is to say, {1 1 1}<1 1 0> slip deformation is dominant [27]. Irradiation-induced defects hinder the dislocation glide causing twinning to dominate the deformation.

Oono, Naoko; Kasada, Ryuta; Higuchi, Toru; Sakamoto, Kan; Nakatsuka, Masafumi; Hasegawa, Akiko; Kondo, Sosuke; Iwata, Noriyuki Y.; Matsui, Hideki; Kimura, Akihiko

2013-11-01

202

Review of recent irradiation-creep results  

SciTech Connect

Materials deform faster under stress in the presence of irradiation by a process known as irradiation creep. This phenomenon is important to reactor design and has been the subject of a large number of experimental and theoretical investigations. The purpose of this work is to review the recent experimental results to obtain a summary of these results and to determine those research areas that require additional information. The investigations have been classified into four subgroups based on the different experimental methods used. These four are: (1) irradiation creep using stress relaxation methods, (2) creep measurements using pressurized tubes, (3) irradiation creep from constant applied load, and (4) irradiation creep experiments using accelerated particles. The similarity and the differences of the results from these methods are discussed and a summary of important results and suggested areas for research is presented. In brief, the important results relate to the dependence of creep on swelling, temperature, stress state and alloying additions. In each of these areas new results have been presented and new questions have arisen which require further research to answer. 65 references.

Coghlan, W.A.

1982-05-01

203

Light scattering studies of irradiated ?- and ?-carrageenan  

NASA Astrophysics Data System (ADS)

The relationships between the molecular weight (Mw) and the characteristic decay time distribution function G( ?) of irradiated kappa ( ?-) and iota ( ?-) carrageenan were studied by static and dynamic light scattering (DLS). Mw and the characteristic decay time ( ?-1) are both steep decreasing exponential function with radiation dose. The dynamic behavior of irradiated ?-carrageenan was compared to irradiated ?-carrageenan by DLS. The intensity correlation function of both carrageenans shifted towards shorter relaxation times with increasing radiation dose. Irradiated ?-carrageenan like ?-carrageenan exhibits power law behavior at 0-50 kGy (at 0.05-0.1M KCl) indicating similar gelation behaviors. The temperature at which transition from coil to helix takes place (conformational transition temperature) decreases with increasing irradiation dose. A new faster relaxation mode appears at around 0.1-1 ms for both carrageenans between 100 and 150 kGy. Maximum peak height for this mode is at 100 kGy which corresponds to the optimum biological activity of ?- and ?-carrageenan.

Abad, L. V.; Nasimova, I. R.; Aranilla, C. T.; Shibayama, M.

2005-05-01

204

Disinfestation of different cereal products by irradiation  

NASA Astrophysics Data System (ADS)

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.

Kovcs, E.; Kiss, I.; Boros, A.; Horvth, Ny.; Tth, J.; Gyulai, P.; Szalma, .

205

ESR spectroscopic properties of irradiated gum Arabic.  

PubMed

Electron spin resonance (ESR) spectra of irradiated gum Arabic with doses between 0.5 and 5 kGy were studied. A linear relationship between the absorbed dose and the intensities of the ESR spectra was observed. ESR spectra of irradiated gum Arabic showed a decay of relative concentrations of free radicals originated by radiation and the production of at least two species of free radicals with half-times: 3.3 and 125.4 h. The results of spectral simulations for these radical groups were giso=2.0046; A=1.2 mT and gx=gy=2.0062, gz=2.0025. Hydration and dehydration of irradiated gum Arabic returns the ESR spectrum to its initial state before irradiation. The results show that ESR can be used as simple and reliable method to detect irradiated gum Arabic up to 60 days after initial radiation with doses on the order of 5 kGy. PMID:23870902

Leonor, S J; Gmez, J A; Kinoshita, A; Calandreli, I; Tfouni, E; Baffa, O

2013-12-01

206

COBALT-60 Gamma Irradiation of Shrimp.  

NASA Astrophysics Data System (ADS)

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 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.

Sullivan, Nancy L. B.

207

Cobalt-60 gamma irradiation of shrimp  

SciTech Connect

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.

Sullivan, N.L.B.

1993-01-01

208

The effect of gamma irradiation on injectable human amnion collagen  

SciTech Connect

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.

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

1989-08-01

209

Dosimetry procedures for an industrial irradiation plant  

NASA Astrophysics Data System (ADS)

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.

Grahn, Ch.

210

Irradiation chemistry in the outer solar system  

NASA Astrophysics Data System (ADS)

The dark, reddish tinged surfaces of icy bodies in the outer solar are usually attributed to the long term irradiation of simple hydrocarbons such as methane leading to the loss of hydrogen and the production of long carbon chains. While 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 possible detections of ethane on more methane-poor Pluto and Quaoar. We have obtained deep high signal-to-noise spectra of Makemake from 1.5 to 2.5 microns in an attempt to trace the radiation chemistry in the outer solar system beyond the initial ethane formation. We present the first astrophysical detections of solid ethylene, acetylene, and possibly propane -- all expected products of the continued irradiation of methane, and use these species to map the chemical pathway from methane to long-chain hydrocarbons.

Brown, Michael E.

2014-11-01

211

Irradiated homologous costal cartilage for augmentation rhinoplasty  

SciTech Connect

Although the ideal reconstructive material for augmentation rhinoplasty continues to challenge plastic surgeons, there exists no report in the literature that confines the use of irradiated homologous costal cartilage, first reported by Dingman and Grabb in 1961, to dorsal nasal augmentation. The purpose of this paper is to present a retrospective analysis of the author's experience using irradiated homologous costal cartilage in augmentation rhinoplasty. Twenty-seven dorsal nasal augmentations were performed in 24 patients between 16 and 49 years of age with a follow-up ranging from 1 to 27 months. Good-to-excellent results were achieved in 83.3% (20 of 24). Poor results requiring revision were found in 16.7% (4 of 24). Complication rates included 7.4% infection (2 of 27) and 14.8% warping (4 of 27). The resorption rate was zero. These results compare favorably with other forms of nasal augmentation. Advantages and disadvantages of irradiated homologous costal cartilage are discussed.

Lefkovits, G. (Lenox Hill Hospital, New York, NY (USA))

1990-10-01

212

Neutrophil myeloperoxidase destruction by ultraviolet irradiation  

SciTech Connect

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.

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

1988-01-01

213

Irradiation creep of vanadium-base alloys.  

SciTech Connect

A study of irradiation creep in vanadium-base alloys is underway with experiments in the Advanced Test Reactor (ATR) and the High Flux Isotope Reactor (HFIR) in the US. Test specimens are thin-wall sealed tubes with internal pressure loading. The results from the initial ATR irradiation at low temperature (200-300 C) to a neutron damage level of 4.7 dpa show creep rates ranging from {approx}0 to 1.2 x 10{sup {minus}5}/dpa/MPa for a 500-kg heat of V-4Cr-4Ti alloy. These rates were generally lower than reported from a previous experiment in BR-10. Because both the attained neutron damage levels and the creep strains were low in the present study, however, these creep rates should be regarded as only preliminary. Substantially more testing is required before a data base on irradiation creep of vanadium alloys can be developed and used with confidence.

Tsai, H.; Matsui, H.; Billone, M. C.; Strain, R. V.; Smith, D. L.

1998-05-18

214

Laboratory for Characterization of Irradiated Graphite  

SciTech Connect

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.

Karen A. Moore

2010-03-01

215

Magnetic phase formation in irradiated austenitic alloys  

NASA Astrophysics Data System (ADS)

Iron-based austenitic alloys are often observed to develop magnetic properties during irradiation, possibly associated with the radiation-induced acceleration of ferrite phase formation. Some of the parametric sensitivities of this phenomenon have been addressed using a series of alloys irradiated in the BOR-60 reactor at 593 K. An increase in magnetic phase amount for all alloys was observed over the 0-12 dpa dose range. However, magnetic phase (ferrite according to TEM results) did not appear to continuously increase at higher doses (above 12 dpa) but did tend to saturate. The formation of a magnetic phase in austenitic stainless steels during irradiation at 593 K appeared to be sensitive to alloy composition. It was found that silicon and manganese accelerated ferrite accumulation in the dose range of 0-12 dpa, whereas carbon and probably molybdenum resisted it. Also, an increase in grain size resisted ferrite formation, but cold work was found to stimulate it.

Gussev, M. N.; Busby, J. T.; Tan, L.; Garner, F. A.

2014-05-01

216

Detection of irradiated wheat by germination  

NASA Astrophysics Data System (ADS)

A 5day germination test was used to identify irradiated wheat. Wheat was irradiated and then germinated in dishes at 25-28C for 5 days. Germination was inhibited with the dose of 3.3 kGy. Almost all grains did not germinate at 10 kGy. The growth of shoots and roots was retarded at 0.33 kGy and seriously inhibited at 0.5 kGy or over. The average lentgh of shoots at 0.5 kGy was about 20 mm and the shoots failed to grow. This effect was irreversible during postirradiation storage. It is a good index for identification of irradiated wheat. The effects of wheat varieties and old seed on germination were studied.

Zhu, S.; Kume, T.; Ishigaki, I.

1993-07-01

217

Growth-irradiance relationships in phytoplankton  

SciTech Connect

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.

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

1985-03-01

218

Enucleation versus plaque irradiation for choroidal melanoma.  

PubMed

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. PMID:3174030

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

1988-07-01

219

Status of food irradiation in the world  

NASA Astrophysics Data System (ADS)

The status of food irradiation in the world in 2005 was investigated using published data, a questionnaire survey and direct visits. The results showed that the quantity of irradiated foods in the world in 2005 was 405,000 ton and comprised 1,86,000 ton (46%) for disinfection of spices and dry vegetables, 82,000 ton (20%) for disinfestation of grains and fruits, 32,000 ton (8%) for disinfection of meat and fish, 88,000 ton (22%) for sprout inhibition of garlic and potato, and 17,000 ton (4%) of other food items that included health foods, mushroom, honey, etc. Commercial food irradiation is increasing significantly in Asia, but decreasing in EU.

Kume, Tamikazu; Furuta, Masakazu; Todoriki, Setsuko; Uenoyama, Naoki; Kobayashi, Yasuhiko

2009-03-01

220

Migration and sensory evaluation of irradiated polymers  

NASA Astrophysics Data System (ADS)

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.

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

2004-09-01

221

Electroslag remelt processing of irradiated vanadium alloys  

NASA Astrophysics Data System (ADS)

This paper describes experimental efforts to investigate the potential of a slag remelting process for reducing radioactivity of irradiated vanadium alloys used in a fusion power production facility. The experiment determined the removal characteristics of four surrogate transmutation isotopes significant to accident safety expected in a V?5Ti?5Cr alloy irradiated under fusion conditions (Ca, Y, to simulate Sc, Mn, and Ar). Removal of these isotopes could decrease the accident risk of reprocessing irradiated vanadium and reusing it in fusion reactors. An electroslag remelt furnace was used in the experiment to melt and react the constituents using a calcium fluoride slag. The process achieved 90% removal of calcium and over 99% removal of yttrium. Analyses indicate that 40% of the manganese has been removed. Argon analysis of the refined ingots indicates that 99% of the argon was removed from the vanadium alloy.

Carmack, W. J.; Smolik, G. R.; McCarthy, K. A.

1996-10-01

222

Irradiation effects on borosilicate waste glasses  

SciTech Connect

The effects of alpha decay on five borosilicate glasses containing simulated nuclear high-level waste oxides were studied. Irradiations carried out at room temperature were achieved by incorporating 1 to 8 wt % /sup 244/Cm/sub 2/O/sub 3/ in the glasses. Density changes and stored-energy build-up saturated at doses less than 2 x 10/sup 21/ alpha decays/kg. Damage manifested by stored energy was completely annealed at 633/sup 0/K. Positive and negative density changes were observed which never exceeded 1%. Irradiation had very little effect on mechanical strength or on chemical durability as measured by aqueous leach rates. Also, no effects were observed on the microstructure for vitreous waste glasses, although radiation-induced microcracking could be achieved on specimens that had been devitrified prior to irradiation.

Roberts, F.P.

1980-06-01

223

Phototoxicity testing by online irradiation and HPLC.  

PubMed

A high-performance liquid chromatography (HPLC) system was developed for the determination of drug photostability and phototoxicity based on an automated column-switching system with aqueous online UV-A irradiation and hyphenated organic separation of the drug and its photoproducts. The photoreactor is built with an poly(ethylene-co-tetrafluoroethylene) (ETFE) reaction coil knitted around a UV-A light source. The chromatographic separation was performed with two special C18 columns, which are also suitable for using with pure water as eluent. Degradation of chlorpromazine (CPZ) by ultraviolet light was investigated at pH 7 and pH 3. Furthermore chlorpromazine was irradiated in the presence of guanosine-5-monophosphate (GMP) in pH 7 buffered solution, leading to a new photoproduct. In the pH 3 irradiation studies of CPZ and GMP, no reaction was detected between the molecules. PMID:17058072

Schrder, Sven; Surmann, J P

2006-11-01

224

Health risk assessment of irradiated topaz  

SciTech Connect

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.

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

1993-01-01

225

Irradiation properties of T0 chopper components  

NASA Astrophysics Data System (ADS)

We investigated the irradiation properties of the components of a T0 chopper. The organic materials in the rotor bearing grease, the magnetic fluids in seals, and the rubber in the timing belt, as well as the semiconductor materials in the rotation sensor and motor encoder, were all irradiated with high-energy ?-rays up to 100 kGy. No significant damage that shortens the lifetime of a T0 chopper was observed for the mechanical components. However, the semiconductor components were damaged by the irradiation. For the rotation sensor system detecting the rotor phase, the signal from a marker on the rotor shaft was transmitted outside the shielding by an optical fiber with radiation-proofing and the electrical circuits were removed from the beamline shielding. The lifetime of the motor encoder possibly meets the requirement for the maintenance period of the T0 chopper.

Itoh, Shinichi; Ueno, Kenji; Ohkubo, Ryuji; Sagehashi, Hidenori; Funahashi, Yoshisato; Yokoo, Tetsuya

2011-10-01

226

BPX insulation irradiation program test results  

SciTech Connect

The toroidal field coil insulation for the Burning Plasma Experiment (BPX) is expected to receive a radiation dose of nearly 10{sup 10} rad and to withstand significant mechanical stresses. An irradiation test program was performed at the Idaho National Engineering Laboratory (INEL) using the Advanced Technology Reactor (ATR) for irradiations to doses on the order of 3 {times} 10{sup 10} rad. The flexure and shear strength with compression of commercially procured sheet material were reported earlier. A second series of tests has been performed to slightly higher dose levels with vacuum impregnated materials, glass strand material, and Spaulrad-S sheet samples. Vacuum impregnation with a Shell 9405 resin and 9470 hardener was used to produce bonded copper squares and flexure samples of both pure resin and resin with S-glass. A new test fixture was developed to test the bonded samples in shear without applied compression. The Spaulrad-S flexure samples demonstrated a loss of strength with irradiation, similar to previous results. The pure resin lost nearly all flexibility, while the S-glass-reinforced samples retained between 30% and 40% of the initial flexure strength. The S-glass strands showed a 30% loss of strength at the higher dose level when tested in tension. The bonded copper squares had a low room-temperature shear strength of approximately 17 MPa before irradiation, which was unchanged in the irradiated samples. Shear testing of unirradiated bonded copper squares with ten different types of surface treatment revealed that the low shear strength resulted from the polyurethane primer used. In the later series of test, the epoxy-based primers and DZ-80 from Ciba-Geigy did much better, with shear strengths on the order of 40 MPa. These samples also demonstrated a resistance to cryogenic shock. One irradiated bonded sample was tested up 10 210 MPa in compression, the limit of the test fixture, without failure.

McManamy, T.J. (Oak Ridge National Lab., TN (United States)); Kanemoto, G. (EG and G Idaho, Inc., Idaho Falls, ID (United States)); Snook, P.G. (Princeton Univ., NJ (United States). Plasma Physics Lab.)

1991-01-01

227

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

NASA Astrophysics Data System (ADS)

The shelf-life of packed minced meat has been increased at least threefold at 4C 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.

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

228

Separation of sodium-22 from irradiated targets  

DOEpatents

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.

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

1996-01-01

229

Heavy-Section Steel Irradiation Program  

SciTech Connect

Maintaining the integrity of the reactor pressure vessel (RPV) in a light-water-cooled nuclear power plant is crucial in preventing and controlling severe accidents that have the potential for major contamination release. Because the RPV is the only key safety-related component of the plant for which a redundant backup system does not exist, it is imperative to fully understand the degree of irradiation-induced degradation of the RPV's fracture resistance that occurs during service. For this reason, the Heavy-Section Steel Irradiation (HSSI) Program has been established.

Rosseel, T.M.

2000-04-01

230

Irradiation effects studies of NERVA materials  

NASA Technical Reports Server (NTRS)

Several materials used in the NERVA project were irradiated at cryogenic temperatures to neutron fluences between 10 to the 17th and 10 to the 19th power newtons per square centimeter. Tensile properties were determined over a temperature range to evaluate the effects of irradiation on the material properties. The expected radiation damage typical of other materials was observed. A general increase in strength and decrease in ductility occurred. The effects at liquid nitrogen temperatures are more pronounced since radiation induced defects are not annealed out.

Demastry, J. A.; Merrick, T. P.

1972-01-01

231

Behavior of lithium in irradiated solar cells.  

NASA Technical Reports Server (NTRS)

The current state of the art in radiation resistant lithium-doped silicon solar cells is reviewed. Fabrication techniques are reviewed. Characteristics of lithium-doped cells are discussed. Behavior of lithium-doped cells during 1 MeV electron irradiation are studied for various types of cells. Effects of variations in lithium and oxygen concentration are shown and discussed. Capacitance measurements at various voltages, frequencies and temperatures are used to detect charges in lithium donor concentration and the formation of defects during irradiation. Physical models to explain the observed effects are presented.

Carter, J. R., Jr.; Downing, R. G.

1971-01-01

232

FMIT - the fusion materials irradiation test facility  

SciTech Connect

A joint effort by the Hanford Engineering Development Laboratory (HEDL) and Los Alamos Scientific Laboratory (LASL) has produced a preliminary design for a Fusion Materials Irradiation Test Facility (FMIT) that uses a high-power linear accelerator to fire a deuteron beam into a high-speed jet of molten lithium. The result is a continuous energy spectrum of neutrons with a 14-MeV average energy which can irradiate material samples to projected end-of-life levels in about 3 years, with a total accumulated fluence of 10/sup 21/ to 10/sup 22/ n/cm/sup 2/.

Liska, D.J.

1980-01-01

233

Schistosoma mansoni: cercarial responses to irradiance changes  

SciTech Connect

Cercariae of Schistosoma mansoni alternate between active swimming and passive drifting. They began swimming in response to either an increase or decrease in irradiance experienced during the passive phase. The number of cercariae reacting to a shadow was proportional to the magnitude of the stimulus. The shadow response may be mediated by the cercaria's ciliary receptors. About half as many cercariae reacted to an irradiance increase as to an equivalent decrease. This report is the first quantitative study of photosensory stimulus-response relationships in schistosome cercariae.

Saladin, K.S.

1982-02-01

234

Radiostability of pharmaceuticals under different irradiation conditions  

NASA Astrophysics Data System (ADS)

In this paper, the products studied are cefazolin, glucagon and dobutamine HCl. The radioresistance of pharmaceuticals may depend on the conditions of irradiation. The best is to irradiate the drugs in solid state and the chemical transformations can be reduced also by lowering the temperature of the liquid. In solid state, the dose rate has no influence on the decomposition for the selected molecules and it should be noted that drug excipients selected for bioavailability reasons are not always radioprotectors. These results are important from a technical point of view in pharmaceutical industry.

Crucq, Anne-Sophie; Deridder, Vronique; Tilquin, Bernard

2005-02-01

235

Long-Term Solar Irradiance Variability  

NASA Technical Reports Server (NTRS)

Measurements of the solar energy throughout the solar spectrum and understanding its variability provide important information about the physical processes and structural changes in the solar interior and in the solar atmosphere...The aim of this paper is to discuss the solar-cycle-related long-term changes in solar total and UV irradiances. The spaceborne irradiance observations are compared to ground-based indices of solar magnetic activity, such as the Photometric Sunspot Index, full disk magnetic flux, and the Mt. Wilson Magnetic Plage Strength Index.

Pap, J. M.

1996-01-01

236

Neutron irradiation of Am-241 effectively produces curium  

NASA Technical Reports Server (NTRS)

Computer study was made on the production of multicurie amounts of highly alpha-active curium 242 from americium 241 irradiation. The information available includes curium 242 yields, curium composition, irradiation data, and production techniques and safeguards.

Anderson, R. W.; Milstead, J.; Stewart, D. C.

1967-01-01

237

10 CFR 36.13 - Specific licenses for irradiators.  

...NUCLEAR REGULATORY COMMISSION LICENSES AND RADIATION SAFETY REQUIREMENTS FOR IRRADIATORS...listed in 36.53 that describes the radiation safety aspects of the procedures. ...managing the irradiator, specifically the radiation safety responsibilities and...

2014-01-01

238

Arrays for Use at the Cobalt Irradiation Facility.  

National Technical Information Service (NTIS)

This report describes current arrays used to hold and position objects for irradiation in the AFRRT 60Co irradiation facility. The arrays are specifically designed for use with nonhuman primates, canines, ferrets, guinea pigs, rats, mice, spores, cells, a...

C. D. Pitcher, J. C. Myska, J. G. Broom, R. C. Bhatt, T. L. Adams

1997-01-01

239

Nonintrusive irradiated fuel inventory confirmation technique  

SciTech Connect

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.

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

1980-01-01

240

Irradiation of superconducting niobium cavities with protons  

Microsoft Academic Search

Electropolished and anodized niobium TE011X-band cavities with Q values up to 2 1010 and critical magnetic flux densities Bacc up to 87 mT were irradiated at room temperature with 1- and 3-MeV protons and fluences up to 1 1016 cm-2. Neither the Q values nor Bacc were influenced by this to any considerable extent.

H. Martens; K. Wholleben

1973-01-01

241

Low energy electron irradiation of an apple  

E-print Network

simulation. A software package, MCNP (Monte Carlo N-Particle), was used to simulate an electron beam irradiation with a 1.0, 1.5 and 2.0 MeV sources on an apple modeled by interconnecting two spheres. The apple radii were 4.4 cm (perpendicular to its axis...

Brescia, Giovanni Batista

2012-06-07

242

Seperation of neptunium from irradiated uranium targets  

Microsoft Academic Search

A new chemical method based in two separation steps was developed to isolate235Np from uranium targets irradiated with charged particles. Neptunium and plutonium are separated from uranium and most of the fission products by ion exchange. Then, neptunium is isolated from plutonium and remaining contaminants by extraction chromatography with tributyl phosphate in hydrochloric acid solution. High decontamination was achieved.

L. F. Bellido; V. J. Robinson; H. E. Sims

1993-01-01

243

Performance validation of an irradiance redistribution guide  

NASA Astrophysics Data System (ADS)

Science Applications International Corporation has used a unique nonimaging-optical global optimization computer code, NICOS, to design an innovative secondary concentrator for the National Renewable Energy Laboratory (NREL). NICOS allows for the optimal design of such devices to achieve a variety of irradiance distributions on a desired target. The case of interest to NREL called for a uniform irradiance of concentrated sunlight over a relatively large area and at a reasonable working distance from the exit of the device. Because the irradiance at the nominal focal point of NREL's High-Flux Solar Furnace (HFSF) was reshaped from a near- Gaussian distribution to a nearly uniform one, the designs generated have been called irradiance redistribution guides (IRG). A design featuring reentrant optics was selected for fabrication and testing. This IRG has been fabricated and tested at the HFSF to compare predicted and measured performance. The IRG's performance is close to the theoretical predictions. Much of the performance difference can be explained by discrepancies between the actual HFSF performance relative to that assumed in the NICOS predictions. This IRG will be useful for applications in which uniform solar concentration at moderate flux is required. In general, the design methodology and resulting devices can provide a new way to satisfy diverse flux tailoring needs.

Lewandowski, Allan; Bingham, Carl; Shatz, Narkis E.; Bortz, John C.

1997-10-01

244

Vol. [VOL], No. [ISS]: 111 Irradiance Rigs  

E-print Network

Vol. [VOL], No. [ISS]: 1­11 Irradiance Rigs Hong Yuan UMass Amherst, Disney Interactive Studios should be evaluated analytically or in a custom rig. This can increase the efficiency of deferred render techniques can be used to efficiently compute the coefficients of a spatial rig model based on the actual

Montréal, Université de

245

Minimizing material damage using low temperature irradiation  

NASA Astrophysics Data System (ADS)

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.

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

2012-08-01

246

Hydrodynamics of Highly Irradiated Planetary Atmospheres  

Microsoft Academic Search

Among the discovered extrasolar planets, a large fraction are close-in giant planets orbiting with periods of only a few days. Unlike Jupiter, intense stellar irradiation and slow rotation due to tidal locking drive unique flow dynamics across the surfaces of these planets. Current and ongoing transit and photometric monitoring campaigns have allowed us an unprecedented look the energy distribution resulting

Ian Dobbs-Dixon

2008-01-01

247

Monitoring pathogens from irradiated agriculture products  

NASA Astrophysics Data System (ADS)

The final food and environmental safety assessment of agriculture product irradiation can only be determined by product history. Product history will be used for future research and development, regulations, commercial practices and implementation of agriculture and food irradiation on a regional basis. The commercial irradiator treats large varieties and amounts of products that are used in various environments. It, in time, will generate a large data base of product history. Field product monitoring begins when food irradiation progresses from the pilot/demonstration phase to the commercial phase. At that time, it is important that there be in place a monitoring system to collect and analyze field data. The systems managers, public health authorities and exotic disease specialists will use this information to assess the reduction of food pathogens on the populace and the environment. The common sources of monitoring data are as follows: 1) Host Monitoring a) Medical Diagnosis b) Autopsy c) Serology Surveys 2) Environmental Monitoring a) Sentinel b) Pest Surveys/Microbial Counts c) Sanitary Inspections 3) Food Industries Quality Assurance Monitoring a) End Product Inspection b) Complaints c) Continual Use of the Product

Butterweck, Joseph S.

248

Heterogeneous oxidative degradation in irradiated polymers  

Microsoft Academic Search

When polymeric materials are irradiated in the presence of air, oxygen-diffusion effects can, depending upon dose rate, lead to oxidative degradation which occurs only near the edges. This report describes the use of several recently developed techniques which are of general use for studying heterogeneous degradation in commerical polymeric materials. The techniques discussed are: optical evaluation of cross-sectioned, polished samples;

R. L. Clough; K. T. Gillen; C. A. Quintana

1984-01-01

249

Fuel testing and post irradiation examination  

Microsoft Academic Search

From international nuclear industries fair; Basel, Switzerland (16 Oct ; 1972). The UKAEA carries out irradiation testing of fuels for gascooled, water-; cooled and fast reactors in the Windscale Advanced Gas Cooled Reactor, the ; Winfrith Steam Generating Heavy Water Reactor and the Dounreay Fast Reactor ; respectively, together with the Materials Testing Reactors DIDO and PLUTO at ; Harwell.

P. W. Mummery; F. J. Barclay; J. S. Nairn

1972-01-01

250

Studies of Solar EUV Irradiance from SOHO  

NASA Technical Reports Server (NTRS)

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.

Floyd, Linton

2002-01-01

251

Hyperparathyroidism After Irradiation for Childhood Malignancy  

SciTech Connect

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.

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

252

Evolutionary Effects of Irradiation in Cataclysmic Variables  

E-print Network

The orbital evolution of cataclysmic variables in which the companion is illuminated by a fraction of the accretion luminosity consists of irradiation-driven limit cycles on thermal timescales, superimposed on a secular evolution toward shorter periods due to systemic angular momentum losses. We show that positive orbital period derivatives during bright phases are a natural consequence of the expansion of the companion during high mass transfer phases in the limit cycle. The irradiation instability may be enhanced by consequential angular momentum losses, CAML, accompanying the limit cycle. We investigate the secular evolution of cataclysmic binaries under the combined effects of irradiation and CAML and show that faster than secular transfer fluctuations that occur during these cycles can account for the observed dispersion in disk luminosities or estimated accretion rates at a given orbital period. If indeed irradiation-driven and CAML--assisted mass transfer fluctuations on timescales faster than secular occur, as discussed in this paper, then we may be able to predict the relative abundances of the different types of cataclysmic variable at a given orbital period. For example this mechanism may explain the relative paucity of dwarf novae with respect to nova-like variables between 3 and 4 hours.

P. McCormick; J. Frank

1998-01-31

253

SOLVENT FREE CHEMICAL TRANSFORMATION USING MICROWAVE IRRADIATION  

EPA Science Inventory

Microwave-expedited solvent-free synthetic processes will be described that involve the exposure of neat reactants to microwave (MW) irradiation in the presence of supported reagents or catalysts on mineral oxides. Recent developments will be presented on the synthetic utility o...

254

Measuring Degradation Rates Without Irradiance Data  

Microsoft Academic Search

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

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

2011-01-01

255

Measuring degradation rates without irradiance data  

Microsoft Academic Search

A method to report photovoltaic (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 using a

Steve Pulver; Daniel Cormode; Alex Cronin; Dirk Jordan; Sarah Kurtz; Ryan Smith

2010-01-01

256

Irradiation effects on fuels for space reactors  

SciTech Connect

A review of irradiation-induced swelling and gas release experience is presented here for the three principal fuels UO/sub 2/, UC, and UN. The primary advantage of UC and UN over UO/sub 2/ is higher thermal conductivity and attendant lower fuel temperature at equivalent pellet diameter and power density, while UO/sub 2/ offers the distinct benefit of well-known irradiation performance. Irradiation test results indicate that at equivalent burnup, temperature, and porosity conditions, UC experiences higher swelling than UO/sub 2/ or UN. Fission gas swelling becomes important at fuel temperatures above 1320 K for UC, and at somewhat higher temperatures for UO/sub 2/ and UN. Evidence exists that at equivalent fuel temperatures and burnups, high density UO/sub 2/ and UN experience comparable swelling behavior; however, differences in thermal conductivity influence overall irradiation performance. The low conductivity of UO/sub 2/ results in higher thermal gradients which contribute to fuel microcracking and gas release. As a result UO/sub 2/ exhibits higher fractional gas release than UN, at least or burnups up to about 3%.

Ranken, W.A.; Cronenberg, A.W.

1984-01-01

257

Health Risk Assessment of Irradiated Topaz  

Microsoft Academic Search

Radiation-produced blue topaz, indistinguishable from natural blue topaz, is produced by several different techniques. Published information on radionuclides present, activity levels, equipment necessary to detect activated nuclides and dosimetric assessment is lacking. Using a 60 megawatt nuclear reactor, fifty-one samples of colorless topaz from Nigeria, Sri Lanka, India and Brazil were irradiated with thermal and fast neutron fluences ranging from

Kevin Lyle Nelson

1991-01-01

258

Sucrose synthesis in gamma irradiated sweet potato  

SciTech Connect

Effect of ..cap alpha..-irradiation carbohydrate metabolism was examined to elucidate mechanism of sucrose accumulation in sweet potato (SP). Enzymes examined were: ..beta..-amylase, phosphorylase, phosphoglucomutase, phosphoglucose isomerase, sucrose phosphate synthetase and sucrose synthetase. Irradiated SP (Red Jewell) sucrose was synthesized to yield 10.7% after 4 d PI. Activities of sugar synthesizing enzymes in irradiated SP were enhanced to different degrees using 100-200 Krad and 3 d PI at 24/sup 0/C. Phosphorylase and phosphoglucomutases specific activities reached 2.4 and 1.8 folds, respectively compared to control SP. ..beta..-amylase, phosphoglucose isomerase, sucrose synthetase and sucrose phosphate synthetase were also affected to yield 1.2, 1.3, 1.3 and 1.2 folds, respectively compared to controls. It is believed that amylase hydrolyzed starch to glucose which is converted to fructose by phosphoglucose isomerase. Sucrose is then formed by sucrose phosphate synthetase and/or sucrose synthetase leading to its accumulation. The irradiated SP was used for alcohol fermentation leading to 500 gal. of 200 proof ethanol/acre (from 500-600 bushels tuber/acre).

Ailouni, S.; Hamdy, M.K.; Toledo, R.T.

1987-01-01

259

Continuous wave laser irradiation of explosives  

SciTech Connect

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.

McGrane, Shawn D.; Moore, David S.

2010-12-01

260

The Sun and Climate Solar Irradiance  

E-print Network

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

Walter, Frederick M.

261

Dynamic nuclear polarization of irradiated targets  

Microsoft Academic Search

We have irradiated and studied dynamic nuclear polarization in ammonia, deuterated ammonia, butanol, borane ammonia, methylamine, ethane and lithium borohydride in order to test these substances for potential use as polarized target materials. These studies were conducted using a polarized target system operating at a temperature of 1K and a magnetic field of 5T. The target system was set up

M. L. Seely; A. Amittay; M. R. Bergstrom; S. K. Dhawan; V. W. Hughes; R. F. Oppenheim; K. P. Schueler; P. A. Souder; K. Kondo; S. Miyashita; K. Morimoto; S. J. St. Lorant; Y.-N. Guo; A. Winnacker

1983-01-01

262

Climatic change due to solar irradiance changes  

Microsoft Academic Search

Solar irradiance reconstructions back to 1874 are used to estimate the effect of the Sun on global-mean temperature. The importance of the history effect of the Sun on global-mean temperature. The importance of the history effect, whereby recent temperature changes may be influenced significantly by past forcing changes, is evaluated. Modelled temperature changes are shown to be relatively insensitive to

T. M. L. Wigley; S. C. B. Raper

1990-01-01

263

Solar UV irradiation and dermal photoaging  

Microsoft Academic Search

The skin is increasingly exposed to ambient UV-irradiation thus increasing risks for photooxidative damage with long-term detrimental effects like photoaging, characterized by wrinkles, loss of skin tone and resilience. Photoaged skin displays alterations in the cellular component and extracellular matrix with accumulation of disorganized elastin and its microfibrillar component fibrillin in the deep dermis and a severe loss of interstitial

Meinhard Wlaschek; Iliana Tantcheva-Por; Lale Naderi; Wenjian Ma; Lars Alexander Schneider; Ziba Razi-Wolf; Jutta Schller; Karin Scharffetter-Kochanek

2001-01-01

264

Irradiated luncheon meat: microbiological, chemical and sensory characteristics during storage  

Microsoft Academic Search

To investigate the effect of gamma irradiation on the shelf-life of luncheon meat, packs were exposed to doses of 0, 1, 2, 3 and 4 kGy in a 60Co package irradiator. Irradiated and non-irradiated samples were stored at refrigeration temperatures (14C). Microbial population, chemical changes and sensory properties were evaluated every 2 weeks during 14 weeks of storage. The results

M Al-Bachir; A Mehio

2001-01-01

265

Radiation effect on PMMA POF under gamma-ray irradiation  

Microsoft Academic Search

An irradiation test was performed for polymethylmethacrylate plastic optical fibers under gamma-ray irradiation in order to use the fiber in low-level radiation environments. Under gamma-ray irradiation at a high dose rate, only a large radiation-induced transmission loss at wavelengths less than 700 nm was observed. Under irradiation at a low dose rate, the loss was small and other two characteristic

K. Toh; S. Nagata; B. Tsuchiya; T. Shikama

2007-01-01

266

Production of seedless watermelon using soft-X-irradiated pollen  

Microsoft Academic Search

A new method for producing seedless watermelon (Citrullus lanatus) in diploid plants using soft-X-irradiated pollen is described. Fruit set at almost the same rate despite soft-X-irradiation. Empty seeds were produced in the watermelon cultivars Benikodama and Fujihikari TR following hand pollination using soft-X-irradiated pollen. Soft-X-irradiation doses of 8001000Gy resulted in small empty seeds in Fujihikari TR, whereas 4001000Gy doses gave

Keita Sugiyama; Masami Morishita

2000-01-01

267

IRRADIATION EFFECTS ON THE PHYSICAL CHARACTERISTICS OF SEWAGE SLUDGE  

SciTech Connect

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.

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

2004-10-05

268

In vitro irradiation system for radiobiological experiments  

PubMed Central

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 20days 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 20Gy 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

2013-01-01

269

Effects and consequences of prenatal irradiation.  

PubMed

After a brief introduction about the historic development of risk estimates and maximum permissible doses of ionizing radiation, the risks of prenatal irradiation are discussed. Experimental data mainly obtained with mice indicate that the most important risk exists during the period of organogenesis and concerns the induction of malformations. Although in man this period lies between about 10 and 80 days after fertilization for most organs, the main development of the brain occurs later, namely between the 8th and 15th week after conception. Data from Japanese victims of the atomic bomb explosions above Hiroshima and Nagasaki indicate that during development the brain is the most sensitive organ to irradiation and maximal sensitivity is found between the 8th and 15th week after fertilization. A dose of one Gray received during this period induces a severe mental retardation in about 45% of the newborns. The dose response relationship is not significantly different from a linear one without a threshold dose. Studies of intelligence and school performance have shown that 1 Gray received during the 8th-15th week causes a shift of the average intelligence of about 30 points. Irradiation before the 8th week and after the 25th week had no effect on intelligence or mental retardation. During the 16th and 25th week sensitivity was about one fourth of that during the 8th-15th week. Although the irradiation of the embryo and fetus should be avoided as much as possible, the new data have led to an abandonment of the so-called 10-day rule. Generally an accidental irradiation of the embryo or fetus of less than 5 cGy is not considered as a medical indication for abortion. Retrospective studies showed that mothers from children who died from leukemia or other childhood tumors, had been subjected to a diagnostic irradiation of the pelvis or lower abdomen more frequently than mothers from children that did not develop a tumor. It has been estimated that prenatal sensitivity for induction of leukemia and tumors is higher than sensitivity after birth. However, it is still in discussion, whether the relationship between prenatal irradiation and a higher incidence of tumors is of a causal nature. PMID:2692643

Vos, O

1989-06-01

270

Irradiation Embritlement in Alloy HT-9  

SciTech Connect

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.

Serrano De Caro, Magdalena [Los Alamos National Laboratory

2012-08-27

271

Void swelling and irradiation creep in austenitic and martensitic stainless steels under cyclic irradiation  

NASA Astrophysics Data System (ADS)

A high purity austenitic FeCrNiMo alloy and DIN 1.4914 martensitic stainless steel were irradiated with 6.2 MeV protons. The pulsed operation of a tokamak fusion reactor was simulated by simultaneous cycling of beam, temperature and stress similar to that anticipated in the NET (Next European Torus) design. Void swelling and irradiation creep of the FeCrNiMo alloy under cyclic and stationary conditions were identical within the experimental error. The martensitic steel showed no swelling at the present low doses (~0.2 dpa). The plastic deformation under continuous and cyclic irradiation was essentially determined by thermal creep. During irradiation the electrical resistivity of FeCrNiMo slightly increased, probably due to swelling, while that of DIN 1.4914 linearly decreased, probably due to segregation effects.

Zhiyong, Zhu; Jung, Peter; Klein, Horst

1993-07-01

272

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...

273

Accessing Solar Irradiance Data Products From the LASP Interactive Solar IRradiance Datacenter (LISIRD)  

Microsoft Academic Search

The Laboratory for Atmospheric and Space Physics (LASP) is enhancing the LASP Interactive Solar IRradiance Datacenter (LISIRD) to provide access to a comprehensive set of solar spectral irradiance measurements. LISIRD has recently been updated to serve many new datasets and models, including sunspot index, photometric sunspot index, Lyman-alpha, and magnesium-II core-to-wing ratio. A new user interface emphasizes web-based interactive visualizations,

A. Ware Dewolfe; A. Wilson; D. M. Lindholm; C. K. Pankratz; M. Snow; T. N. Woods

2009-01-01

274

Modeling Equilibrium Moisture Content of ?-Ray Irradiated Rough Rice  

Microsoft Academic Search

Experimental studies show that gamma irradiation dose affects the values of equilibrium moisture content of grain at the same relative humidity and temperature of ambient. Values of the equilibrium moisture content decreased with increasing dose of ?-ray irradiation during both adsorption and desorption. Factor of irradiation dose was included in three widely used models for equilibrium moisture content; the parameters

Y. Yu; J. Wang

2006-01-01

275

Irradiation Applications in Vegetables and Fruits: A Review  

Microsoft Academic Search

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

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

2009-01-01

276

Pancreatic islet transplantation: Immuno-alteration with ultraviolet irradiation  

Microsoft Academic Search

To circumvent rejection of allogeneic pancreatic islet grafts, we have examined the use of ultraviolet (UV) irradiation to inactivate allostimulatory cells in blood prior to their use for the induction of donor-specific tolerance and to decrease the immunogenicity of pancreatic islets by direct UV irradiation. UVB (280320 nm) irradiation of blood can effectively abrogate lymphocyte stimulatory capacity in an MLC,

Mark A. Hardy; Henry T. Lau; Collin Weber; Keith Reemtsma

1984-01-01

277

EFFECTS OF X IRRADIATION ON ENZYME SYNTHESIS DURING LIVER REGENERATION  

Microsoft Academic Search

Twenty-four different enzymes or enzyme systems were assayed in ; regenerating rat liver from control and irradiated animals at various times after ; partial hepatectomy. X irradiation, either of the whole liver region or of an ; exteriorized liver lobule, interfered with the accumulation of only three of ; these enzymes: deoxycytidylate deaminase, thymidine phosphorylase, and NAD ; pyrophosphorylase. Irradiation

D. K. Myers

1962-01-01

278

Response of Tradescantia albiflora to growth irradiance: Change versus changeability  

Microsoft Academic Search

Most chloroplasts undergo changes in composition, function and structure in response to growth irradiance. However, Tradescantia albiflora, a facultative shade plant, is unable to modulate its light-harvesting components and has the same Chl a\\/Chl b ratios and number of functional PS II and PS I reaction centres on a Chl basis at all growth irradiances. With increasing growth irradiance, Tradescantia

Jan M. Anderson; Wah Soon Chow; Youn-Il Park; Linda A. Franklin; Sharon P.-A. Robinson; Philip R. van Hasselt

2001-01-01

279

Creep behavior of epoxy resin during irradiation at cryogenic temperature  

Microsoft Academic Search

Creep tests of an epoxy resin during bending and irradiation have been carried out to investigate the synergistic effects of radiation and stress on mechanical properties of the resin. Simultaneous application of stress and irradiation on the epoxy resin enhanced creep rates in comparison with the application of stress on an irradiated sample. In order to clarify the mechanism of

Tetsuya Nishiura; Shigehiro Nishijima; Toichi Okada

1999-01-01

280

Phenomenological model of yield strength temperature dependence for irradiated materials  

Microsoft Academic Search

In this work, it is formulated a phenomenological model to describe a yield strength temperature dependence of polycrystalline materials that have undergone irradiation and mechanical experiences in a wide temperature interval including structure levels of plastic deformation. The proposed model shows a good agreement with experimental data of both irradiated and no irradiated materials. Also it is shown that empirical

V. V. Krasil'Nikov; S. E. Savotchenko; A. A. Parkhomenko

2010-01-01

281

Biodosimetry using micronucleus assay in acute partial body therapeutic irradiation  

Microsoft Academic Search

Biological dosimetry provides information on the absorbed dose and its distribution in the body for an early assessment of irradiation consequences in exposed individuals. In this study, an effort has been made to see the applicability of biological dosimetry using micronuclei assay for dose estimation in therapeutic irradiation of cancer patients in acute high dose partial body irradiation. Dose estimation

Srinivasan Senthamizhchelvan; G. S. Pant; G. K. Rath; P. K. Julka; O. Nair

2009-01-01

282

Neutron irradiation effects in GaN-based blue LEDs  

Microsoft Academic Search

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.

Chyishiun Li; S. Subramanian

2003-01-01

283

Relationships of photosynthetically active radiation and shortwave irradiance  

Microsoft Academic Search

Hourly measurements of solar irradiance in the wave band excluding photosynthetically active radiation (PAR) and solar irradiance (SI) were made over a 12-month period at the National Observatory of Athens, for obtaining the ratios of PAR to SI. These irradiance ratios exhibit dependence on sky conditions, with slightly larger values being observed under cloudy skies and seasonal variations, attributable to

G. Papaioannou; N. Papanikolaou; D. Retalis

1993-01-01

284

Large Animal Irradiation J. Daniel Bourland, PhD  

E-print Network

Large Animal Irradiation J. Daniel Bourland, PhD Professor Department of Radiation Oncology · Summary #12;Irradiation Issues same as for humans · Animal size (nominal L x W x H) · Photon energy (to: Total Body Irradiation dose escalation study · 15 animals, matched by sex, weight · Animal handling

285

Dermal grafts to bony defects in irradiated and nonirradiated tissues  

SciTech Connect

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.

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

1984-10-01

286

Total solar irradiance during the Holocene F. Steinhilber,1  

E-print Network

Total solar irradiance during the Holocene F. Steinhilber,1 J. Beer,1 and C. Fro¨hlich2 Received 20 solar irradiance covering 9300 years is presented, which covers almost the entire Holocene. This reconstruction is based on a recently observationally derived relationship between total solar irradiance

Wehrli, Bernhard

287

SPECTRAL SOLAR IRRADIANCE AND ITS ENTROPIC EFFECT ON EARTH'S CLIMATE  

E-print Network

SPECTRAL SOLAR IRRADIANCE AND ITS ENTROPIC EFFECT ON EARTH'S CLIMATE Wei Wu1 , Yangang Liu1 of the spectral solar irradiance (SSI) at the top of the Earth's atmosphere by the Solar Radiation and Climate the total solar irradiance (TSI) at the top of the Earth's atmosphere (TOA) varies little (only about 0

288

SOLAR IRRADIANCE FORECASTING FOR THE MANAGEMENT OF SOLAR ENERGY SYSTEMS  

E-print Network

SOLAR IRRADIANCE FORECASTING FOR THE MANAGEMENT OF SOLAR ENERGY SYSTEMS Detlev Heinemann Oldenburg or progress with respect to the development of solar irradiance forecasting methods. Heck and Takle (1987 presents different state-of-the-art approaches to solar irradiance forecasting in different time scales

Heinemann, Detlev

289

RETHINKING SATELLITE BASED SOLAR IRRADIANCE MODELLING R. W. Mueller  

E-print Network

RETHINKING SATELLITE BASED SOLAR IRRADIANCE MODELLING R. W. Mueller , K.F. Dagestad ¡ , R-German Aerospace Center; 5-Ecole des Mines de Paris ABSTRACT Accurate solar irradiance data are not only Heliosat-3 a new type of solar irradiance scheme is developed. This new type will be based on radiative

Heinemann, Detlev

290

Total solar irradiance trend during solar cycles 21 and 22  

Microsoft Academic Search

Results from Activity Cavity Radiometer Irradiance Monitor (ACRIM) experiments show an upward trend in total solar irradiance of 0.036 percent per decade between the minima of solar cycles 21 and 22. The trend follows the increasing solar activity of recent decades and, if sustained, could raise global temperatures. Trends of total solar irradiance near this rate have been implicated as

R. C. Willson

1997-01-01

291

How the inclination of Earth's orbit affects incoming solar irradiance  

E-print Network

How the inclination of Earth's orbit affects incoming solar irradiance L. E. A. Vieira,1 A. Norton of the evolution of climate. Accurate measurements of total solar irradiance (TSI) variability by instruments to millennia time-scales. Additionally, long- term changes in Earth's orbit modulate the solar irradiance

292

Creation of a composite solar ultraviolet irradiance data set  

Microsoft Academic Search

Characterization of long-term solar ultraviolet (UV) irradiance variations is important for understanding the radiative forcing of Earth's atmosphere. Extending such a characterization to multidecadal timescales requires the merging of multiple satellite data sets. Currently available irradiance data sets show both absolute offsets and time-dependent differences that vary between spectral ranges. We have created a composite spectral UV irradiance data set

Matthew T. DeLand; Richard P. Cebula

2008-01-01

293

LISIRD: Where to go for Solar Irradiance Data  

Microsoft Academic Search

LASP, the Laboratory for Atmospheric and Space Physics, has been providing web access to solar irradiance measurements, reference spectra, composites and model data covering the solar spectrum from .1 to 2400 nm through LISIRD, the LASP Interactive Solar IRradiance Datacenter. No single instrument can measure the solar spectral irradiance from X-rays to the IR, but the ensemble of LASP instruments

A. Wilson; C. K. Pankratz; D. M. Lindholm; M. Snow; B. Knapp; D. Woodraska; B. Templeman; T. Woods; F. Eparvier; J. Fontenla; J. Harder; M. Bill

2008-01-01

294

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

NASA Astrophysics Data System (ADS)

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.

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

2002-03-01

295

Influence of gamma ray irradiation on metakaolin based sodium geopolymer  

NASA Astrophysics Data System (ADS)

Effects of gamma irradiation on metakaolin based Na-geopolymer have been investigated by external irradiation. The experiments were carried out in a gamma irradiator with 60Co sources up to 1000 kGy. Various Na-geopolymer with three H2O/Na2O ratios have been studied in terms of hydrogen radiolytic yield. The results show that hydrogen production increases linearly with water content. Gamma irradiation effects on Na-geopolymer microstructure have been investigated with porosity measurements and X-ray pair distribution function analysis. A change of pore size distribution and a structural relaxation have been found after gamma ray irradiation.

Lambertin, D.; Boher, C.; Dannoux-Papin, A.; Galliez, K.; Rooses, A.; Frizon, F.

2013-11-01

296

Electron beam irradiation effects on ethylene-tetrafluoroethylene copolymer films  

NASA Astrophysics Data System (ADS)

The effects of electron beam irradiation on ethylene-tetrafluoroethylene copolymer (ETFE) films were studied. Samples were irradiated in air at room temperature by a universal electron beam accelerator for doses ranging from 100 to 1200 kGy. Irradiated samples were investigated with respect to their chemical structure, thermal characteristics, crystallinity and mechanical properties using FTIR, differential scanning calorimeter (DSC) and universal mechanical tester. The interaction of electron irradiation with ETFE films was found to induce dose-dependent changes in all the investigated properties. A mechanism for electron-induced reactions is proposed to explain the structure-property behaviour of irradiated ETFE films.

Nasef, Mohamed Mahmoud; Saidi, Hamdani; Dahlan, Khairul Zaman M.

2003-12-01

297

Gamma irradiation influence on physical properties of milk proteins  

NASA Astrophysics Data System (ADS)

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.

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

2004-09-01

298

Irradiation creep in structural materials at ITER operating conditions  

SciTech Connect

Irradiation creep is plastic deformation of a material under the influence of irradiation and stress. Below the regime of thermal creep, there remains a deformation mechanism under irradiation that is weakly temperature dependent and clearly different from thermal creep. This is irradiation creep. Both stress and irradiation are required for irradiation creep. Irradiation creep studies for applications in the past focused mostly on liquid metal fast breeder reactors where temperatures are usually above 400{degrees}C. Fusion reactors, especially nearterm devices such as the ITER will have components operating at temperatures as low as 100{degrees}C exposed to high neutron fluxes. Theories of irradiation creep based on steady-state point defect concentrations do not predict significant irradiation creep deformation at these temperatures; however, data from research reactors show that irradiation creep strains at 60{degrees}C are as high or higher than at temperatures above 300{degrees}C for austenitic stainless steels. Irradiation creep of nickel has also been observed at cryogenic temperatures.

Grossbeck, M.L.

1994-09-01

299

Neurite outgrowth on fluorinated polyimide film micropatterned by ion irradiation  

NASA Astrophysics Data System (ADS)

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.

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

2003-05-01

300

Specificity of proton irradiation effects on polymers  

NASA Astrophysics Data System (ADS)

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.

Briskman, B. A.

2007-12-01

301

EPR study of ?-irradiated cholesteryl methyl carbonate  

NASA Astrophysics Data System (ADS)

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).

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

2014-11-01

302

Atmospheric turbidity determination from irradiance ratios  

SciTech Connect

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.

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

1997-12-31

303

Radiotherapeutic alternatives for previously irradiated recurrent gliomas  

PubMed Central

Re-irradiation for recurrent gliomas has been discussed controversially in the past. This was mainly due to only marginal palliation while being associated with a high risk for side effects using conventional radiotherapy. With modern high-precision radiotherapy re-irradiation has become a more wide-spread, effective and well-tolerated treatment option. Besides external beam radiotherapy, a number of invasive and/or intraoperative radiation techniques have been evaluated in patients with recurrent gliomas. The present article is a review on the available methods in radiation oncology and summarizes results with respect to outcome and side effects in comparison to clinical results after neurosurgical resection or different chemotherapeutic approaches. PMID:17760992

Combs, Stephanie E; Debus, Jurgen; Schulz-Ertner, Daniela

2007-01-01

304

Prediction of Irradiation Spectrum Effects in Pyrochlores  

NASA Astrophysics Data System (ADS)

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.

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

2014-09-01

305

RESTORATION INDUCED BY CATALASE IN IRRADIATED MICROORGANISMS  

E-print Network

Working with the bacterial strain Escherichia coli K-12 which had been irradiated with heavy doses of ultraviolet light, Monod, Torriani, and Jolit (1949) have recently observed a new type of restoration phenomenon. Mter irradiation, the rate of survival, estimated by colony counts on agar plates, seemed to increase with the size of plating, that is with the number of cells plated, as though the dead bacteria contributed some restoring factor. This same factor was found in extracts from various organs of the rabbit. After preliminary investigation, these authors identified the restoring factor as catalase. Ferrous sulfate exerted a similar effect but to a lesser degree. In addition, the restoring action was heavily favored by the administration of some visible light, insufficient in itself for giving a notable restoration. This paper presents results on further development of this study. I

Latarjet; Luis Renato Caldas

306

Response of electrospun CNT composites to irradiation  

NASA Astrophysics Data System (ADS)

In this work, we investigate the suitability of Electrospinning as a manufacturing technique to produce CNT-polymer composites with a response to light. This objective is explored by way of developing a precursor solution comprised of a polymeric blend, suitable of CNT dispersion and further electrospinning. The MWCNTs were dispersed using Sodium dodecyl sulfate (SDS) and added to a polymeric solution consisting of Polydimethylsiloxane (PDMS) and Polymethyl methacrylate (PMMA) in Tetrahydrofuran (THF) and Dimethylformamide (DMF). The dispersion of the CNTs during synthesis was studied using UV-VIs and XRD techniques. Fibers electrospun out of this precursor and their response to irradiation will also be discussed. Fiber morphology was characterized by SEM and the response to irradiation was examined by photoelectric conductivity.

Rosa, S. M.; Crespo, J. P.; Santiago-Avils, J. J.; Ramos, I.; Campo, E. M.

2012-06-01

307

Fractionated total body irradiation for metastatic neuroblastoma  

SciTech Connect

Twelve patients over one year old with neuroblastoma (NBL) metastatic to bone and bone marrow entered a study of adjuvant low-dose, fractionated total body irradiation (TBI). Six children who achieved a ''complete clinical response'' following chemotherapy (cyclophosphamide and adriamycin) and surgical resection of the abdominal primary received TBI (10 rad/fraction to totals of 100-120 rad/10-12 fx/12-25 days). Two children received concurrent local irradiation for residual abdominal tumor. The intervals from cessation of chemotherapy to documented progression ranged from 2-16 months, not substatially different from patients receiving similar chemotherapy and surgery without TBI. Three additional children with progressive NBL received similar TBI (80-120 rad/8-12 fx) without objective response.

Kun, L.E. (Medical Coll. of Wisconsin, Madison); Casper, J.T.; Kline, R.W.; Piaskowski, V.D.

1981-11-01

308

Modification of polyethylene terephthalate by proton irradiation  

NASA Astrophysics Data System (ADS)

Polyethylene terephthalate (PET) films were irradiated with 3 MeV proton beams at different fluences. The microhardness, electrical, thermal and structural studies were carried out using microhardness tester, LCR meter, thermogravimetric analysis (TGA) and FTIR spectroscopy. Vickers' hardness has been observed to increase with the fluence. The true bulk hardness of the film was obtained at loads greater than 400 mN. The AC electrical conductivity is practically unaffected by irradiation up to a frequency of 10 kHz, but it is found to increase exponentially at a frequency of 300 kHz. The loss factor and dielectric constant are observed to change appreciably with the fluence. It is observed that there is no significant change in the stability of the polymer up to the fluence of 1014 ions cm(-2) as revealed by TGA and FTIR spectroscopy.

Singh, N. L.; Shah, N.; Desai, C. F.; Singh, K. P.; Arora, S. K.

2004-08-01

309

Long-term effects of orbital irradiation  

SciTech Connect

This retrospective study is a review of 18 patients who received radiotherapy to the orbit between the ages of 1 month and 10 years. Patients were followed for 7-21 years in an attempt to define the effects of orbital irradiation on a growing child. None of the patients in the study was spared injurious effects on soft tissue or bone, but soft tissue appeared to be more vulnerable to radiation than bone. Orbital irradiation caused soft tissue deficits of the upper face in 100% of the patients. Sixty-seven percent of patients had soft tissue deformities of the midface, and 13% had soft tissue deformities of the lower face. Bony deficits were found in the upper face in 67% of the patients, the midface in 50%, and the lower face in 6%. This study found no correlation between age and time of radiotherapy on the effects of facial growth.

Guyuron, B.; Dagys, A.P.; Munro, I.R.

1987-11-01

310

Exploiting geometrical irradiation possibilities in MRT application  

NASA Astrophysics Data System (ADS)

Microbeam Radiation Therapy (MRT) has the potential to treat infantile brain tumors when other kinds of radiotherapy would be excessively toxic to the developing normal brain. MRT uses extraordinarily high doses of X-rays but provides unusual resistance to radioneurotoxicity, presumably from the rapid migration of regenerative endothelial cells from dose "valleys" into dose "peaks", i.e., into directly irradiated micro-slices of tissues. We will present a novel irradiation geometry which results in a tolerable valley dose for the normal tissue and a decreased peak-to-valley dose ratio (PVDR) in the tumor area by applying an innovative cross-firing technique. We propose an MRT technique to orthogonally crossfire two arrays of parallel, nonintersecting, mutually interspersed microbeams that produces tumoricidal doses with small PVDRs where the arrays meet and tolerable radiation doses to normal tissues between the microbeams proximal and distal to the tumor in the paths of the arrays.

Bruer-Krisch, E.; Requardt, H.; Rgnard, P.; Corde, S.; Siegbahn, E. A.; LeDuc, G.; Blattmann, H.; Laissue, J.; Bravin, A.

2005-08-01

311

Nanodot formation induced by femtosecond laser irradiation  

NASA Astrophysics Data System (ADS)

The femtosecond laser generation of ZnSe nanoscale features on ZnSe surfaces was studied. Irradiation with multiple exposures produces 10-100 nm agglomerations of nanocrystalline ZnSe while retaining the original single crystal structure of the underlying material. The structure of these nanodots was verified using a combination of scanning transmission electron microscopy, scanning electron microscopy, and atomic force microscopy. The nanodots continue to grow hours after irradiation through a combination of bulk and surface diffusion. We suggest that in nanodot formation the result of ultrafast laser induced point defect formation is more than an order of magnitude below the ZnSe ultrafast melt threshold fluence. This unique mechanism of point defect injection will be discussed.

Abere, M. J.; Chen, C.; Rittman, D. R.; Kang, M.; Goldman, R. S.; Phillips, J. D.; Torralva, B.; Yalisove, S. M.

2014-10-01

312

Titanium implants in irradiated dog mandibles  

SciTech Connect

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.

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

1989-08-01

313

Precipitation during irradiation: an experimental example  

SciTech Connect

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.

Gelles, D.S.

1981-01-01

314

Precipitation during irradiation: an experimental example  

SciTech Connect

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.

Gelles, D.S.

1981-01-01

315

Online Irradiation Control by Means of PET  

NASA Astrophysics Data System (ADS)

Positron emission tomography (PET) is a dedicated tool for quality assurance in IBT. By measuring the spatial distribution of positron emitters generated via nuclear interactions between projectiles and atomic nuclei of the tissue during the therapeutic irradiation, conclusions on the accuracy of the dose localization can be drawn. In the following, the physical background as well as the technical realization of PET is depicted. Furthermore, current PET installations for quality assurance of proton and IBT are presented.

Fiedler, Fine; Kunath, Daniela; Priegnitz, Marlen; Enghardt, Wolfgang

316

Commercial food irradiation in the United States  

Microsoft Academic Search

During the first half of the Decade-of-the-90s commercial food irradiation in the U.S., led by disinfection of dry food ingredients, especially spices and seasonings, has been steadily increasing. This is partly because the media, and through it the general public, is now receiving much more accurate information, and, the controversy that raged from the mid-1980s through the early 1990s has

George Giddings

1996-01-01

317

X-ray irradiation of yeast cells  

Microsoft Academic Search

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.

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

1997-01-01

318

Radiation Pneumonitis and Esophagitis in Thoracic Irradiation  

Microsoft Academic Search

Without regard to normal tissue complications, most tumors could likely be eradicated by irradiation through escalating the\\u000a dose. However, normal tissue complications limit our ability to administer the dose necessary for tumor control. Tumor control\\u000a probability (TCP) for a given tumor is represented by a sigmoid curve in which an increase in dose results in greater tumor\\u000a cell kill. Likewise,

Jeffrey Bradley; Benjamin Movsas

319

Biodosimetry estimate for high-LET irradiation  

Microsoft Academic Search

The purpose of this paper is to prepare for an easy and reliable biodosimeter protocol for radiation accidents involving high-linear\\u000a energy transfer (LET) exposure. Human peripheral blood lymphocytes were irradiated using carbon ions (LET: 34.6keV?m?1), and the chromosome aberrations induced were analyzed using both a conventional colcemid block method and a calyculin A\\u000a induced premature chromosome condensation (PCC) method. At

Z. Z. Wang; W. J. Li; D. J. Zhi; X. G. Jing; W. Wei; Q. X. Gao; B. Liu

2007-01-01

320

Behaviour of Dielectric Materials Under Electron Irradiation  

NASA Astrophysics Data System (ADS)

The fundamental aspects of charge trapping in electron irradiated insulators have been investigated by means of a scanning electron microscope (SEM). The technique commonly used to perform charge injection, their transport and trapping ability is based on the absorbed current method and the SEM mirror effect. In this work, we have studied the influence of temperature on the charge trapping/diffusion during injection time at industrial porcelain samples given by S.T.E.G (Tunisian Society of Electricity and Gas).

Hachicha, O.; Ghorbel, N.; Kallel, A.; Fakhfakh, Z.

2007-09-01

321

Low temperature electron irradiation of tellurium  

Microsoft Academic Search

Tellurium single crystal samples with a hole concentration of 3 1014\\/cm2 were irradiated at 10 K with electrons with an energy of 0.6 and 1 MeV. In the range investigated resistivity and Hall-coeficient RH both decreased linearly with the integrated electron flux. The hole generation rate was 0.09 cm-1 and 0.47 cm-1 for 0.6 and 1 MeV electrons, respectively.

E. Gmeljn; R. Stapf; P. Klemt; G. Landwehr; W. Lichtenberg; A. Przybylski

1971-01-01

322

Bound vacancy interstitial pairs in irradiated silicon  

Microsoft Academic Search

Frenkel defects are produced by MeV electron irradiation of Si with an introduction rate of ? 1 cm?1 and we show that defect concentrations as high as 1019 cm?3 can be frozen in at 4 K. From X-ray diffraction we deduce that a large fraction of the defects is stabilized in the form of close Frenkel pairs and that the

H. Zillgen; P. Ehrhart

1997-01-01

323

[Stereotactic irradiation in head and neck cancers].  

PubMed

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

Benham, C; Lapeyre, M; Thariat, J

2014-01-01

324

[Adenosine triphosphate synthesis induced by ultraviolet irradiation].  

PubMed

Effect of UV-irradiation on non-aqueous solutions of adenine nucleotide mixture of the presence of inorganic phosphate was studied. Solutions of ADP sodium salts containing AMP and ATP admixtures and of inorganic phosphate in DMSO and DMPA and ethylene glycol were illuminated with the lamp dPIII-500. It has been shown that along with nucleotide disintegration and complex formation ATP synthesis takes place, which is evidenced by an increase of relative ATP content in experimental specimens. PMID:7260149

Lozinova, T A; Brzhevskaia, O N; Nedelina, O S; Kaiushin, L P

1981-01-01

325

Radiation-induced aperiodicity in irradiated ceramics  

SciTech Connect

The experimental program is designed to reveal details of the metamict (amorphization, or crystal-to-glass) transformation in irradiated ceramics (silica compounds, less-connected lead phosphates). The silica compounds were amorphized using electrons, neutrons, and ions, while the phosphates were amorphized using ions (primarily) and neutrons. Energy-filtered electron microdiffraction, high-resoltuion transmission electron microscopy, and high-performance liquid-phase chromatography are being used.

Hobbs, L.W.

1993-02-01

326

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

SciTech Connect

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.

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

1993-12-31

327

Irradiation response and stability of nanoporous materials  

SciTech Connect

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.

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

328

Local brain heavy ion irradiation induced Immunosuppression  

NASA Astrophysics Data System (ADS)

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.

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

329

Stress modified welding process for irradiated materials  

NASA Astrophysics Data System (ADS)

Prior investigations have shown that catastrophic cracking occurs during the repair welding of irradiated material. This cracking has been linked to minute amounts of helium in the material which are produced during irradiation. Experiments have shown that type 316 stainless steel, containing helium levels greater than 2.5 atomic parts per million (appm), is susceptible to cracking upon cooling when welded using the gas tungsten arc (GTA) process under lateral constraint. The cracking has been hypothesized to be caused by stress-assisted helium bubble growth and repture at grain boundaries. In this study, the effects of stress state on the helium bubble growth process were investigated. Autogenous bead-on-plate welds were produced in type 316 stainless steels, containing 256 appm helium. Welds were produced using normal lateral constraint and compressive lateral constraint. The application of a small compressive constraint suppressed previously observed catastrophic cracking. Detailed examinations conducted after welding showed a dramatic change in helium bubble morphology. Grain boundary bubble growth along directions parallel to the weld was suppressed. The results suggest that stress state modification may be used to suppress or eliminate helium-induced cracking encountered during the joining of irradiated materials.

Wang, C. A.; Chin, B. A.; Grossbeck, M. L.

330

Protein Quality of Irradiated Brazilian Beans  

NASA Astrophysics Data System (ADS)

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. macaar. 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.

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

1998-06-01

331

Electron Irradiation of Interstellar Ice Analogues  

NASA Astrophysics Data System (ADS)

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).

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

2011-05-01

332

Estimating probability distributions of solar irradiance  

NASA Astrophysics Data System (ADS)

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.

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

2014-07-01

333

Repair welding of irradiated 304 stainless steel  

SciTech Connect

The heat-affected zone (HAZ) of repair welds cracked when patches were welded to the tank wall of a nuclear reactor at the Savannah River Site. The cracking was caused by helium embrittlement. The presence of helium generated in irradiated type 304 stainless steel by neutron interaction with boron and nickel impairs weld repair. Welds on material with as little as one part per million helium generated by exposure to a thermal neutron fluence of 1{times}10{sup 21}n/cm{sup 2} developed substantial cracking in the weld heat-affected zone. Evaluation of conventional welds made on type 304 stainless steel containing 1 to 12 appm helium generated by neutron irradiation, or 3 to 220 appm helium generated by tritium decay, demonstrated cracking of the weld heat-affected zones. A newly developed, low penetration, weld overlay technique mitigates cracking by modifying the stress and temperature profile in the weld heat-affected zone. These results demonstrated the potential for a practical welding alternative to mechanical clamping for repair of irradiated material. The helium embrittlement process proceeds with the formation of helium bubbles, followed by agglomeration and growth of bubbles under the influence of the heat and stress of welding. To determine the effect of stress on weld quality in practical situations, a series of test welds with various conditions of mechanical restraint was evaluated. Generally, higher restraint produced greater cracking of the welds.

Kanne, W.R. Jr.; Chandler, G.T.; Franco-Ferreira, E.A.; Rankin, D.T.; Louthan, M.R. Jr. [Westinghouse Savannah River Co., Aiken, SC (United States)

1995-12-31

334

Magnetic phase formation in irradiated austenitic alloys  

SciTech Connect

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.

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

335

Multivariate Analysis of Solar Spectral Irradiance Measurements  

NASA Technical Reports Server (NTRS)

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.

Pilewskie, P.; Rabbette, M.

2001-01-01

336

Lower Limit on Solar Irradiance Variation  

NASA Astrophysics Data System (ADS)

Helioseismic data reveal that the historical Sun cannot be any dimmer than it is now at activity minimum. Changes in the frequencies of solar oscillations are the most precise probe of irradiance variations over the solar cycle. Using MDI data, Dziembowski and Goode (2005) showed that f-mode changes arise from the direct effect of the evolving magnetic activity, while p-mode changes are due to small, activity induced changes in convective flows very near to the solar surface (turbulent pressure). The f-modes also sharply limit the allowed field growth with activity, and the limit is consistent with the observations of Lin and Rimmele (1999). Combining MDI data with BBSO Ca II K, we find the Sun is smooth at activity minimum and becomes increasingly corrugated with rising activity. The overall physical picture is one in which the Sun is hottest and smoothest at activity minimum, and becomes cooler, more corrugated and irradiant with rising activity. Thus, these results place a lower limit on irradiance variations, consistent with current activity minima, and are roughly consistent with a picture of Spruit (2000) and the behavior of faculae as reported by Berger et al. (2005).

Goode, P. R.

2005-12-01

337

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

SciTech Connect

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)

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

338

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

SciTech Connect

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.

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

339

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

SciTech Connect

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.

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

340

[The adaptive response of first generation offsprings irradiated parents].  

PubMed

In offspring's of first generation irradiated inhabitants of Techa river (fathers, mothers and both parents) the spontaneous level of damaged blood lymphocytes, sensitivity of lymphocytes to the additional acute irradiation in dose 1.0 Gy and radioinduced adaptive response after adaptive (5 cGy) and challenge (1.0 Gy) irradiation 5 h after was studied. The micronuclei test with cytochalasin B as a criteria of the effect have been used. It was shown, that descendents of irradiated parents differ from the control group. The main difference is the significant decrease of the adaptive response frequency in the progeny. In the offspring's of the irradiated fathers and mothers there is no one individuals with the adaptive response; in the offspring's of both irradiated parents the frequency of individuals with adaptive response decreases in control from 19.5% to 6.8%. The distribution of descendents according to response on adaptive irradiation differ significantly from the control distribution and from the each other. And the tendency to the radiosensitivity increase after adaptive irradiation was observed. In the whole joint group of progeny the mean spontaneous cell frequency with micronuclei decreased, but the sensitivity of lymphocytes to the additional acute irradiation doesn't differ from the control. The results of the paper permit to suppose that transgenerational genome instability in human can be determined. Earlier discovered decrease of the adaptive response frequency in the Techa river livings is observed in the offspring's of irradiated fathers, mothers and both parents. PMID:18051680

Akleev, A V; Aleshchenko, A V; Gotlib, V Ia; Kudriashova, O V; Semenova, L P; Serebriany?, A M; Khudiakova, O I; Pelevina, I I

2007-01-01

341

Evaluation of Neutron Irradiated Silicon Carbide and Silicon Carbide Composites  

SciTech Connect

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.

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

2007-03-26

342

Effect of Electron Beam Irradiation on Tensile Strength of Polypropylene  

NASA Astrophysics Data System (ADS)

In this paper, the effects of the intensity of electron beam and the variation with time after irradiation of electron beam on the tensile strength of the polypropylene (PP), which is widely used as medicine containers, were investigated. PP with and without colorants were used first and samples irradiated under various intensity of EB. A tensile test on the irradiated samples with elapsed time after the irradiation of the electron beam was carried out. The effects of those factors on the tensile strength were discussed. The following results were obtained (1) The tensile strength of PP decreased due to the influence of the electron beam irradiation, however the rate of the decrease in strength was small compared with the original one. Furthermore, the rate of the decrease in strength was very small owing to the variation with time after the EB irradiation. (2) The tensile rupture strength of PP increased and the rupture strain owing to the influence of the electron beam irradiation compared with the original one. In addition, these rupture strength increased and the rupture strain decreased along with time after the irradiation of the electron beam. (3) The tensile rupture strain energy of PP decreased owing to the influence of the electron beam irradiation compared with the original one. In addition, the strain energy decreases with time after the irradiation of the electron beam. Moreover, the strength characteristics of PP with colorants received greater influence of electron beam compared with the one without colorants.

Yamada, Hiroshi; Ikeda, Masayuki; Shimbo, Minoru; Miyano, Yasushi

343

Physicochemical and sensory properties of irradiated dry-cured ham  

NASA Astrophysics Data System (ADS)

To determine the effect of different irradiation doses on ready-to-eat (RTE) dry-cured shoulder hams, physicochemical and sensory attributes were analyzed during 8 weeks of refrigerated storage. The results show that irradiation reduced the redness value and increased the 2-thiobarbituric acid-reactive substance (TBARS) value as well as the irradiation aroma during storage. However, ham samples irradiated with 2.5 and 5.0 kGy did not show significant changes in lightness values compared to the control sample during 8 weeks of storage. TBARS values were lower in the sample irradiated with 2.5 kGy than in the other irradiated samples. The total plate counts of the 5.0 kGy-irradiated samples were not measured after 0 weeks. Sensory panels found that the 2.5- and 5.0 kGy-irradiated samples had better overall acceptability scores than the other irradiated samples. It was concluded that treatments with lower levels of irradiation (?5.0 kGy) can enhance the microbial safety and sensory acceptance of dry-cured shoulder hams.

Jin, Sang-Keun; Kim, Chul-Wook; Chung, Ki-Hwa; Jo, Kwang-Keun; Jeong, Jin-Yeon; Hur, In-Chul; Jung, Eun-Young; Joo, Seon-Tea; Yang, Han-Sul

2012-02-01

344

Gamma irradiation treatment of cereal grains for chick diets  

SciTech Connect

Wheat (W), triticale (T), hulled barley (HB), hull-less barley (HLB), hulled oats (HO), and hull-less oats (HLO) were gamma irradiated (/sup 60/Co) at 0, 3, 6 and 9 Mrad to study the effect of irradiation on the nutritional value of cereal grains for chicks. A significant curvilinear relationship between radiation dose and 3-wk body weight of chicks fed irradiated cereals was noted for T, HB, HLB, HO and HLO. Chicks fed W or T showed no effect or lower body weight, respectively, while body weights of chicks fed barley or oat samples were higher with irradiation. The improvement tended to be maximal at the 6 Mrad level. Irradiation significantly improved the gain-to-feed ratio for chicks fed either HO or HLO. Apparent fat retention and tibia ash were higher in chicks fed irradiated HLO than in those fed untreated HLO. In a second experiment chick body weight, apparent amino acid and fat retention, tibia ash, and gain-to-feed ratios were lower in chicks fed autoclaved (121 degrees C for 20 min) barley than in those fed untreated barley. Irradiation (6 Mrad) subsequent to autoclaving barley samples eliminated these effects. Irradiation appears to benefit cereals containing soluble or mucilagenous fiber types as typified by beta-glucan of barley and oats. These fibers appear prone to irradiation-induced depolymerization, as suggested by increased beta-glucan solubility and reduced extract viscosity for irradiated barley and oat samples.

Campbell, G.L.; Classen, H.L.; Ballance, G.M.

1986-04-01

345

Crystallographic analysis of the amorphization caused by ion irradiation: Self-irradiation  

NASA Astrophysics Data System (ADS)

We have examined a mechanism of Si amorphization, by a classical molecular-dynamics, paying attention to whether or not the self-interstitial atom (SIA) clusters were a precursor to amorphization, when a crystalline Si was self-irradiated by several keV ions at a low temperature of 100 K. The pixel mapping (PM) analyzed crystallographically a crystalline to amorphous (CA) transition caused by ion irradiation by means of a set of long-range-order parameters. The spatial distribution of SIAs were also counted by PM. Throughout the sequential self-irradiation, the fraction of isolated SIAs was dominant. Although the fractions were small, we found the significant increase of small SIA clusters, e.g. I2-I4, as the crystalline state was being collapsed. We conclude that those small SIA clusters can be the trigger to enhance the production of more SIAs, and results in CA transition.

Nakagawa, S. T.

2003-05-01

346

Post-irradiation-examination of irradiated fuel outside the hot cell  

SciTech Connect

Because of their high radioactivity, irradiated fuels are commonly examined in a hot cell. However, the Idaho National Laboratory (INL) has recently investigated irradiated U-Mo-Al metallic fuel from the Reduced Enrichment for Research and Test Reactors (RERTR) project using a conventional unshielded scanning electron microscope outside a hot cell. This examination was possible because of a two-step sample-preparation approach in which a small volume of fuel was isolated in a hot cell and shielding was introduced during later stages of sample preparation. The resulting sample contained numerous sample-preparation artifacts but allowed analysis of microstructures from selected areas.

Dawn E. Janney; Adam B. Robinson; Thomas P. O'Holleran; R. Paul Lind; Marc Babcock; Laurence C. Brower; Julie Jacobs; Pamela K. Hoggan

2007-09-01

347

Graphitization of polymer surfaces by scanning ion irradiation  

NASA Astrophysics Data System (ADS)

Graphitization of polymer surfaces was performed by low-energy Ar+ and He+ ion irradiation. A method of scanning irradiation was implemented. It was found that by scanning ion irradiation, a significantly higher electrical conductivity in the graphitized layers can be achieved in comparison with a conventional broad-beam irradiation. The enhancement of the conductance becomes more pronounced for narrower and better collimated ion beams. In order to analyze these results in more detail, the temperature dependence of conductance of the irradiated samples was investigated. The results of measurements are discussed in terms of weak localization corrections to conductance in disordered metals. The observed effects can be explained by enlargement of graphitic patches, which was achieved with the scanning ion irradiation method.

Koval, Yuri

2014-10-01

348

The live cell irradiation and observation setup at SNAKE  

NASA Astrophysics Data System (ADS)

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.

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

2009-06-01

349

Ultraviolet irradiated corneal allografts include antigen scientific unresponsiveness  

SciTech Connect

The effect of ultraviolet (UV) irradiation on the immunogenicity of corneal allografts was examined in a mouse model. BALB/c corneal allografts were exposed to 200 mJ/cm{sup 2} of UVB irradiation immediately prior to heterotopic transplantation of C57BL/6 recipients. Analysis of cytotoxic T lymphocyte (CTL) and delayed-type hypersensitivity (DTH) responses revealed profound impairment of both forms of cell-mediated immunity. Mice grafted with UVB irradiated corneal grafts 7 days prior to immunization with nonirradiated, immunogenic corneal grafts failed to mount either allospecific CTL or DTH responses. Suppression of DTH responses was cyclophosphamide sensitive; C57BL/6 hosts treated with cyclophosphamide one day prior to receiving UVB irradiated corneal grafts developed normal DTH responses. Allospecific suppression could be transferred to naive recipients using spleen cells from host grafted with UV irradiated corneal allografts. The results indicated that UVB irradiation not only rendered corneal allografts nonimmunogenic but also tolerogenic.

Niederkorn, J.Y. (Univ. of Texas, Dallas (United States))

1991-03-15

350

Spectroscopic characterization of ion-irradiated multi-layer graphenes  

NASA Astrophysics Data System (ADS)

Low-energy Ar ions (0.5-2 keV) were irradiated to multi-layer graphenes and the damage process, the local electronic states, and the degree of alignment of the basal plane, and the oxidation process upon ion irradiation were investigated by Raman spectroscopy, soft X-ray absorption spectroscopy (XAS) and in situ X-ray photoelectron spectroscopy (XPS). By Raman spectroscopy, we observed two stages similar to the case of irradiated graphite, which should relate to the accumulations of vacancies and turbulence of the basal plane, respectively. XAS analysis indicated that the number of sp2-hybridized carbon (sp2-C) atoms decreased after ion irradiation. Angle-resolved XAS revealed that the orientation parameter (OP) decreased with increasing ion energy and fluence, reflecting the turbulence of the basal plane under irradiation. In situ XPS shows the oxidation of the irradiated multi-layer graphenes after air exposure.

Tsukagoshi, Akira; Honda, Shin-ichi; Osugi, Ryo; Okada, Hiraku; Niibe, Masahito; Terasawa, Mititaka; Hirase, Ryuji; Izumi, Hirokazu; Yoshioka, Hideki; Niwase, Keisuke; Taguchi, Eiji; Lee, Kuei-Yi; Oura, Masaki

2013-11-01

351

NANOSTRUCTURE PATTERNING UNDER ENERGETIC PARTICLE BEAM IRRADIATION  

SciTech Connect

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.

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

2013-01-31

352

The effects of gamma irradiation on Serratia marcescens  

E-print Network

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...

Bartlett, William Thomas

2012-06-07

353

Deuteron irradiation creep of chemically vapor deposited silicon carbide fibers  

Microsoft Academic Search

Irradiation creep tests were conducted on Textron SCS-6 silicon carbide (SiC) fibers during irradiation with 14 MeV deuterons at 450 and 600C. The fibers are produced by a CVD procedure; their microstructure may therefore be representative for the matrix of a SiC composite. There is a significant radiation induced increase in creep deformation. Both quantities, irradiation creep strain and creep

R. Scholz

1998-01-01

354

Metallographic analysis of irradiated RERTR-3 fuel test specimens  

Microsoft Academic Search

The RERTR-3 irradiation test was designed to investigate the irradiation behavior of aluminum matrix U-MO alloy dispersion fuels under high-temperature, high-fission-rate conditions. Initial postirradiation examination of RERTR-3 fuel specimens has concentrated on binary U-MO atomized fuels. The rate of matrix aluminum depletion was found to be higher than predictions based on low temperature irradiation data. Wavelength Dispersive X-ray Spectroscopy (WDS)

M. K. Meyer; G. L. Hofman; R. V. Strain; C. R. Clark; J. R. Stuart

2000-01-01

355

Effects of electron irradiation on single-walled carbon nanotubes  

Microsoft Academic Search

An experimental investigation of the effects of electron irradiation on Single-Walled Carbon Nanotubes (SWNTs) was conducted. The study focused on the modifications induced to the SWNT structure. SWNTs were irradiated at room temperature using a Transmission Electron Microscope (TEM) at 120eV. The effects of irradiation were observed and characterised using electron microscopy and Raman spectroscopy. Samples of SWNTs were observed

Katherine McDonell; Gwnalle Proust; Luming Shen

2010-01-01

356

Phenomenological model of yield strength temperature dependence for irradiated materials  

Microsoft Academic Search

In this work, it is formulated a phenomenological model to describe a yield strength temperature dependence of polycrystalline\\u000a materials that have undergone irradiation and mechanical experiences in a wide temperature interval including structure levels\\u000a of plastic deformation. The proposed model shows a good agreement with experimental data of both irradiated and no irradiated\\u000a materials. Also it is shown that empirical

V. V. Krasilnikov; S. E. Savotchenko; A. A. Parkhomenko

2010-01-01

357

Correlation of Plasma FL Expression with Bone Marrow Irradiation Dose  

PubMed Central

Purpose Ablative bone marrow irradiation is an integral part of hematopoietic stem cell transplantation. These treatment regimens are based on classically held models of radiation dose and the bone marrow response. Flt-3 ligand (FL) has been suggested as a marker of hematopoiesis and bone marrow status but the kinetics of its response to bone marrow irradiation has yet to be fully characterized. In the current study, we examine plasma FL response to total body and partial body irradiation in mice and its relationship with irradiation dose, time of collection and pattern of bone marrow exposure. Materials/Methods C57BL6 mice received a single whole body or partial body irradiation dose of 18 Gy. Plasma was collected by mandibular or cardiac puncture at 24, 48 and 72 hr post-irradiation as well as 13 weeks post-irradiation. FL levels were determined via ELISA assay and used to generate two models: a linear regression model and a gated values model correlating plasma FL levels with radiation dose. Results At all doses between 18 Gy, plasma FL levels were greater than control and the level of FL increased proportionally to the total body irradiation dose. Differences in FL levels were statistically significant at each dose and at all time points. Partial body irradiation of the trunk areas, encompassing the bulk of the hematopoietically active bone marrow, resulted in significantly increased FL levels over control but irradiation of only the head or extremities did not. FL levels were used to generate a dose prediction model for total body irradiation. In a blinded study, the model differentiated mice into dose received cohorts of 1, 4 or 8 Gy based on plasma FL levels at 24 or 72 hrs post-irradiation. Conclusion Our findings indicate that plasma FL levels might be used as a marker of hematopoietically active bone marrow and radiation exposure in mice. PMID:23505536

Sproull, Mary; Avondoglio, Dane; Kramp, Tamalee; Shankavaram, Uma; Camphausen, Kevin

2013-01-01

358

Laser plasma formed by a gamma-irradiated target  

Microsoft Academic Search

An investigation was made of the interaction of neodymium laser radiation (? = 1.06 ?m) with a sample of ?-irradiated n-type crystalline silicon. The irradiation was performed in a flux of ? photons from 60Co with a power of 1.5 kR\\/s at doses of up to between 1 MR and 10 GR. The results of irradiation were studied using optical

M R Bedilov; Kh B Be?sembaeva; S A Karamysheva; M S Sabitov

1988-01-01

359

Fluorine absorption in dental enamel assisted by UV irradiation  

Microsoft Academic Search

SummaryA new method of dental fluorine prophylaxis based on the chemical reaction induced by UV irradiation in dental enamel has\\u000a been presented. Fluorine ions from a gel topic can be retained to the dental apatite in the lamp-irradiated samples at about\\u000a 70% and in the laser-irradiated samples at about 80% of the maximum deposited value. The19F(p,?)16O nuclear reaction was used

G. Majni; L. Torrisi; G. Molinari

1988-01-01

360

Checking ozone amounts by measurements of UV-irradiances  

NASA Technical Reports Server (NTRS)

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.

Seckmeyer, Gunther; Kettner, Christiane; Thiel, Stephen

1994-01-01

361

Dosimetry for the approval of food irradiation processes  

NASA Astrophysics Data System (ADS)

The use of accurate and precise radiation dosimetry to control the food irradiation process for regulatory purposes is discussed. The various procedures required to establish a thorough dosimetric control, such as commissioning the irradiation facility, process validation and routine control are described. It is concluded that, coupled with an administrative inventory control, dosimetry can provide the guarantee that the process has been correctly applied and regulatory release of irradiated food can be based on accurate and reproducible absorbed dose measurements.

Miller, A.; Chadwick, K. H.

362

Solar Irradiance Variations on Active Region Time Scales  

NASA Technical Reports Server (NTRS)

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.

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

1984-01-01

363

Thermally activated deformation of irradiated reactor pressure vessel steel  

NASA Astrophysics Data System (ADS)

Temperature and strain rate change tensile tests were performed on two VVER 1000-type reactor pressure vessel welds with different contents of nickel in unirradiated and irradiated conditions in order to determine the activation parameters of the contribution of the thermally activated deformation. There are no differences of the activation parameters in the unirradiated and the irradiated conditions as well as for the two different materials. This shows that irradiation hardening preferentially results from a friction hardening mechanism by long-range obstacles.

Bhmert, J.; Mller, G.

2002-03-01

364

Interfractional Target Variations for Partial Breast Irradiation  

SciTech Connect

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.

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

365

Solar Irradiance and Thermospheric Airglow Rocket Experiments  

NASA Technical Reports Server (NTRS)

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.

Solomon, Stanley C.

1998-01-01

366

Safety systems in gamma irradiation facilities.  

PubMed

A new electronic device has been developed to guard against individuals gaining entry through the product entry and exit ports into our irradiation facility for industrial sterilization. This device uses the output from electronic sensors and pressure mats to assure that only the transport cabins may pass through these ports. Any intention of personnel trespassing is detected, the process is stopped by the safety system, and the source is placed in safe position. Owing to a simple construction, the new device enables reliable operation, is inexpensive, easy to implement, and improves the existing safety systems. PMID:9228175

Drndarevic, V

1997-08-01

367

Heat generation by irradiated complex composite nanostructures.  

PubMed

Heating of irradiated metallic e-beam generated nanostructures was quantified through direct measurements paralleled by novel model-based numerical calculations. By comparing discs, triangles, and stars we showed how particle shape and composition determines the heating. Importantly, our results revealed that substantial heat is generated in the titanium adhesive layer between gold and glass. Even when the Ti layer is as thin as 2 nm it absorbs as much as a 30 nm Au layer and hence should not be ignored. PMID:24392799

Ma, Haiyan; Tian, Pengfei; Pello, Josselin; Bendix, Poul Martin; Oddershede, Lene B

2014-02-12

368

Total skin electron irradiation techniques: a review  

PubMed Central

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

Milecki, Piotr; Skorska, Malgorzata; Fundowicz, Dorota

2013-01-01

369

Irradiation effects in high-density polyethylene  

NASA Astrophysics Data System (ADS)

Using molecular dynamics simulations, we have studied the irradiation effects in high density polyethylene. We found that the governing reactions were chain scissioning and generation of free radicals, whereas cross-linking and recombination of chain fragments was rare. We also determined the threshold energy for creating defects in the polyethylene lattice as a function of the incident angle. Our analysis on the damage threshold energy shows that it is strongly dependent on the initial recoil direction and on average two times higher for the carbon atoms than for the hydrogen atoms in the polyethylene chain.

Polvi, Jussi; Nordlund, Kai

2013-10-01

370

Total Body Irradiation (TBI) in Pediatric Patients  

Microsoft Academic Search

\\u000a Abstract\\u000a \\u000a \\u000a Purpose:\\u000a To retrospectively analyze patient characteristics, treatment, and treatment outcome of pediatric patients with hematologic\\u000a diseases treated with total body irradiation (TBI) between 1978 and 2006.\\u000a \\u000a \\u000a \\u000a \\u000a \\u000a Patients and Methods:\\u000a 32 pediatric patients were referred to the Department of Radiation-Oncology at the University of Zurich\\u000a for TBI. Records of regular follow-up of 28 patients were available for review. Patient characteristics

Claudia Linsenmeier; Daniel Thoennessen; Laura Negretti; Jean-Pierre Bourquin; Tino Streller; Urs Martin Ltolf; Susanne Oertel

2010-01-01

371

Broadband infrared luminescence in ?-ray irradiated bismuth borosilicate glasses.  

PubMed

The influence of ?-ray irradiation on the optical properties of Bi(2)O(3)-B(2)O(3)-SiO(2) glass has been investigated. Broadband infrared (IR) emission at 1310 nm with a FWHM over 200 nm is observed in the ?-ray irradiated glass. The IR luminescence depends on the ?-ray irradiation dose and the concentration of Bi(2)O(3). The thermal stability of the ?-ray irradiated IR luminescence center is studied, and the origin of the IR luminescence center has been suggested. PMID:23455121

Shen, Wei; Ren, Jing; Baccaro, Stefania; Cemmi, Alessia; Chen, Guorong

2013-02-15

372

Defective bursa regeneration after irradiation of young thymectomized chickens  

SciTech Connect

The ability of the bursa of Fabricius to regenerate after gamma-irradiation and bone marrow reconstitution was examined in chickens thymectomized (TX) immediately after hatching. Irradiation (2 X 500 R) 3 weeks after hatching was followed by impaired bursa regeneration, as judged both by bursa/body weight ratios and by bursa follicle development 3-6 weeks later in TX as compared to control birds. Germinal center formation in the spleen was deficient, and immune responses to sheep erythrocytes (SRBC) and B. abortus (BA) were moderately reduced in the TX as compared to control birds irradiated at 3 weeks but not in TX birds irradiated at 5 weeks of age.

Bhogal, B.S.; Chi, D.S.; Galton, J.E.; Bell, M.K.; Thorbecke, G.J.

1984-08-01

373

Carbon Irradiated SI-GaAs for Photoconductive THz Detection  

E-print Network

We report here a photoconductive material for THz generation and detection with sub-picosecond carrier lifetime made by C12 (Carbon) irradiation on commercially available semi-insulating (SI) GaAs. We are able to reduce the carrier lifetime of SI-GaAs down to sub-picosecond by irradiating it with various irradiation dosages of Carbon (C12) ions. With an increase of the irradiation dose from ~1012 /cm2 to ~1015 /cm2 the carrier lifetime of SI-GaAs monotonously decreases to 0.55 picosecond, resulting in strongly improved THz pulse detection compared with normal SI-GaAs.

Singh, Abhishek; Surdi, Harshad; Prabhu, S S; S., Mathimalar; Nanal, Vandana; Pillay, R G; Dohler, G H

2014-01-01

374

The fourth SINQ Target Irradiation Program, STIP-IV  

NASA Astrophysics Data System (ADS)

The 4th SINQ Target Irradiation Program (STIP-IV) was performed in 2004 and 2005. More than 1000 specimens from about 40 kinds of materials were irradiated up to 27 dpa and 2300 appm He in the temperature range of 80-550 C. The majority of specimens were irradiated in helium gas environment. Some specimens were irradiated in contact with lead and lead-bismuth eutectic. Neutron radiography inspections on specimen and target rods were performed before and after irradiation, which revealed some interesting features of the target rods with thermal couples. Neutronic calculations were performed using the proton distribution profile obtained by ?-mapping on the beam window of the AlMg3 target container after irradiation. Irradiation parameters of the specimens such as proton and neutron spectra and fluxes, heat deposition, irradiation dose in terms of displacement damage (dpa), helium and hydrogen concentrations were calculated. Most of the specimens were retrieved. But, more than 360 tensile and TEM specimens were lost due to a leak in a specimen rod occurred during irradiation.

Dai, Y.; Brun, R.; Gao, W.; Geissmann, K.; Hahl, S.; Hou, H.; Huang, Y.; Linder, H. P.; Long, B.; Spahr, A.; Vontobel, P.; Wagner, W.; Wang, H. L.; Zanini, L.

2012-12-01

375

Persistent photoconductivity in neutron irradiated GaN  

NASA Astrophysics Data System (ADS)

Unintentionally doped GaN films grown by MOCVD were irradiated with neutrons at room temperature. In order to investigate the influence of neutron irradiation on the optical properties of GaN films, persistent photoconductivity (PPC) and low temperature photoluminescence (PL) measurements were carried out. Pronounced PPC was observed in the samples before and after neutron irradiation without the appearance of a yellow luminescence (YL) band in the PL spectrum, suggesting that the origin of PPC and YL are not related. Moreover, PPC phenomenon was enhanced by neutron irradiation and quenched by the followed annealing process at 900 C. The possible origin of PPC is discussed.

Minglan, Zhang; Ruixia, Yang; Naixin, Liu; Xiaoliang, Wang

2013-09-01

376

Food irradiation: Technology transfer in Asia, practical experiences  

NASA Astrophysics Data System (ADS)

Nordion International Inc., in cooperation with the Thai Office of Atomic Energy for Peace (OAEP) and the Canadian International Development Agency (CIDA) recently completed a unique food irradiation technology transfer project in Thailand. This complete food irradiation technology transfer project included the design and construction of an automatic multipurpose irradiation facility as well as the services of construction and installation management and experts in facility operation, maintenance and training. This paper provides an insight into the many events that led to the succesful conclusion of the world's first complete food irradiation technology transfer project.

Kunstadt, Peter; Eng, P.

1993-10-01

377

Food irradiation in Hungary: commercial processing and development work  

NASA Astrophysics Data System (ADS)

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

Kalman, B.; Szikra, L.; Ferencz, P.

2000-03-01

378

Effect of. gamma. -ray irradiation on alcohol production from corn  

SciTech Connect

Cracked corn was irradiated with ..gamma.. rays at 0-100 Mrad and the effects of the irradiation on sugar yield, susceptibility to enzymatic hydrolysis of starch, yeast growth, and alcohol production were studied. Gamma irradiation at 50 Mrad or greater produced a considerable amount of reducing sugar but little glucose. At lower dosages, ..gamma.. irradiation significantly increased the susceptibility of corn starch to enzymatic hydrolysis, but dosages of 50 Mrad or greater decomposed the starch molecules as indicated by the reduction in iodine uptake. About 12.5% reducing sugar was produced by amylase treatment of uncooked, irradiated corn. This amount exceeded the level of sugar produced from cooked (gelatinized) corn by the same enzyme treatment. The yeast numbers in submerged cultivation were lower on a corn substrate that was irradiated at 50 Mrad or greater compared to that on an unirradiated control. About the same level of alcohol was produced on uncooked, irradiated (10/sup 5/ - 10/sup 6/ rad) corn as from cooked (121 degrees C for 30 min) corn. Therefore, the conventional cooking process for gelatinization of starch prior to its saccharification can be eliminated by irradiation. Irradiation also eliminated the necessity of sterilization of the medium and reduced the viscosity of high levels of substrate in the fermentation broth. (Refs. 10).

Han, Y.W.; Cho, Y.K.; Ciegler, A.

1983-11-01

379

Study on sterilization and storage of enzymatic preparations by irradiation  

NASA Astrophysics Data System (ADS)

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.

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

1993-10-01

380

Irradiated test fuel shipment plan for the LWR MOX fuel irradiation test project  

SciTech Connect

This document outlines the responsibilities of DOE, DOE contractors, the commercial carrier, and other organizations participating in a shipping campaign of irradiated test specimen capsules containing mixed-oxide (MOX) fuel from the Idaho National Engineering and Environmental Laboratory (INEEL) to the Oak Ridge National Laboratory (ORNL). The shipments described here will be conducted according to applicable regulations of the US Department of Transportation (DOT), US Nuclear Regulatory Commission (NRC), and all applicable DOE Orders. This Irradiated Test Fuel Shipment Plan for the LWR MOX Fuel Irradiation Test Project addresses the shipments of a small number of irradiated test specimen capsules and has been reviewed and agreed to by INEEL and ORNL (as participants in the shipment campaign). Minor refinements to data entries in this plan, such as actual shipment dates, exact quantities and characteristics of materials to be shipped, and final approved shipment routing, will be communicated between the shipper, receiver, and carrier, as needed, using faxes, e-mail, official shipping papers, or other backup documents (e.g., shipment safety evaluations). Any major changes in responsibilities or data beyond refinements of dates and quantities of material will be prepared as additional revisions to this document and will undergo a full review and approval cycle.

Shappert, L.B.; Dickerson, L.S.; Ludwig, S.B.

1998-10-16

381

Modeling daylight availability and irradiance components from direct and global irradiance  

Microsoft Academic Search

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.

R. Perez; P. Ineichen; R. Seals; J. Michalsky; R. Stewart

1990-01-01

382

Accessing Solar Irradiance Data Products From the LASP Interactive Solar IRradiance Datacenter (LISIRD)  

NASA Astrophysics Data System (ADS)

The Laboratory for Atmospheric and Space Physics (LASP) is enhancing the LASP Interactive Solar IRradiance Datacenter (LISIRD) to provide access to a comprehensive set of solar spectral irradiance measurements. LISIRD has recently been updated to serve many new datasets and models, including sunspot index, photometric sunspot index, Lyman-alpha, and magnesium-II core-to-wing ratio. A new user interface emphasizes web-based interactive visualizations, allowing users to explore and compare this data before downloading it for analysis. The data provided covers a wavelength range from soft X-ray (XUV) at 0.1 nm up to the near infrared (NIR) at 2400 nm, as well as wavelength-independent Total Solar Irradiance (TSI). Combined data from the SORCE, TIMED-SEE, UARS-SOLSTICE, and SME instruments provide almost continuous coverage from 1981 to the present, while Hydrogen Lyman-alpha (121.6 nm) measurements / models date from 1947 to the present. This poster provides an overview of the LISIRD system, summarizes the data sets currently available, describes future plans and capabilities, and provides details on how to access solar irradiance data through LISIRD interfaces at http://lasp.colorado.edu/lisird/.

Ware Dewolfe, A.; Wilson, A.; Lindholm, D. M.; Pankratz, C. K.; Snow, M.; Woods, T. N.

2009-12-01

383

Heterogeneous thermochemical decomposition of a semi-transparent particle under high-flux irradiation: uniform versus non-uniform irradiation  

NASA Astrophysics Data System (ADS)

The effects of a semi-transparent reacting particle irradiation are analysed using a transient combined heat transfer model. Direct uniform irradiation is found to be favourable for particle heating and decomposition, decreasing the total reaction time by a factor of 3.3 as compared to that for non-uniform irradiation. In both cases heat transfer from the surface to the reaction zone is the process limiting mechanism.

Ebner, Pirmin Philipp; Lipi?ski, Wojciech

2014-07-01

384

Excessive irradiance and antioxidant responses of an Antarctic marine diatom exposed to iron limitation and to dynamic irradiance.  

PubMed

The synergistic effects of iron limitation and irradiance dynamics on growth, photosynthesis, antioxidant activity and excessive PAR (400-700 nm) and UV (280-400 nm) sensitivity were investigated for the Antarctic marine diatom Chaetoceros brevis. Iron-limited and iron-replete cultures were exposed to identical daily irradiance levels, supplied as dynamic (20-1350 micromol m(-2) s(-1)) and constant (260 micromol m(-2) s(-1)) irradiance. After acclimation, growth, maximal quantum yield of PSII (F(v)/F(m)), pigment composition, and the activities of the antioxidant enzymes superoxide dismutase (SOD), ascorbate peroxidase (APX) and glutathione reductase (GR) were determined. Then, excessive irradiance sensitivity was assessed by monitoring pigment composition, F(v)/F(m) and viability loss during a single excessive PAR and UV treatment. Iron limitation reduced growth rates, F(v)/F(m) dynamics, and cellular pigments pools. Cellular pigment concentrations were higher under dynamic irradiance than under constant irradiance but this difference was less pronounced under iron limitation compared to iron-replete conditions. SOD and APX activities increased during dynamic irradiance under iron limitation, suggesting increased radical formation around PSII. Despite these physiological differences, no effects on growth were observed between constant and dynamic irradiance cultivation in iron-limited and iron-replete cells. The applied culturing conditions did not affect glutathione reductase activity in C. brevis. F(v)/F(m) and xanthophyll de-epoxidation dynamics during excessive irradiance were not different for iron-limited and replete cells and viability loss was not found during excessive irradiance. This study revealed photoacclimation differences between iron-limited and iron-replete C. brevis cultures that did not affect growth rates and excessive irradiance sensitivity after acclimation to constant and dynamic irradiance. PMID:18948012

van de Poll, Willem H; Janknegt, P J; van Leeuwe, M A; Visser, R J W; Buma, A G J

2009-01-01

385

Excessive irradiance and antioxidant responses of an Antarctic marine diatom exposed to iron limitation and to dynamic irradiance  

Microsoft Academic Search

The synergistic effects of iron limitation and irradiance dynamics on growth, photosynthesis, antioxidant activity and excessive PAR (400700nm) and UV (280400nm) sensitivity were investigated for the Antarctic marine diatom Chaetoceros brevis. Iron-limited and iron-replete cultures were exposed to identical daily irradiance levels, supplied as dynamic (201350?molm?2s?1) and constant (260?molm?2s?1) irradiance. After acclimation, growth, maximal quantum yield of PSII (Fv\\/Fm), pigment

Willem H. van de Poll; P. J. Janknegt; M. A. van Leeuwe; R. J. W. Visser; A. G. J. Buma

2009-01-01

386

Effect of irradiation temperature and oxygen impurity on the yield strength of T(d, n) neutron irradiated niobium  

Microsoft Academic Search

Tensile tests and microstructural examinations have been conducted on niobium wires and foils with differing oxygen contents following T(d,n) neutron irradiation at 300 K, 475 K, and 675 K. The yield strength of the irradiated wires was strongly dependent on both oxygen content and irradiation temperature. Increasing the oxygen content from 185 to 480 wppM produced 1.6 to 2.0 times

E. R. Bradley; R. H. Jones

1986-01-01

387

Microstructure evolution in austenitic Fe-Cr-Ni alloys irradiated with rotons: comparison with neutron-irradiated microstructures  

NASA Astrophysics Data System (ADS)

Irradiation-induced microstructures of high purity and commercial purity austenitic stainless steels were investigated using proton-irradiation. For high purity alloys, Fe-20Cr-9Ni (HP 304 SS), Fe-20Cr-24Ni and Ni-18Cr-9Fe were irradiated using 3.2 MeV protons between 300C and 600C at a dose rate of 710 -6 dpa/ s to doses up to 3.0 dpa. The commercial purity alloys, CP 304 SS and CP 316 SS were irradiated at 360C to doses between 0.3 and 5.0 dpa. The dose, temperature and composition dependence of the number density and size of dislocation loops and voids were characterized. The changes in yield strength due to irradiation were estimated from Vickers hardness measurements and compared to calculations using a dispersed-barrier-hardening (DBH) model. The dose and temperature dependence of proton-irradiated microstructure (loops, voids) and the irradiation hardening are consistent with the neutron-data trend. Results indicate that proton-irradiation can accurately reproduce the microstructure of austenitic alloys irradiated in LWR cores.

Gan, J.; Was, G. S.

2001-08-01

388

Enhanced radiation damage in irradiated and non-irradiated bystander regions by co-exposure to myosmine.  

PubMed

It is important to evaluate the health effects of radiation concurrent exposure to chemicals in our daily life. Myosmine, an alkaloid in tobacco plants and various edibles and staple foods, has been considered as a co-genotoxic agent in vitro. In the present study, the damage induced by radiation concurrent exposure to myosmine was assessed in human primary cell line AG1522. Myosmine at 5 or 10 mM for 3 h treatment induced a significantly dose-dependent increase in micronucleus (MN) frequencies, but not for 1 mM. However, 1 mM myosmine distinctly enhanced MN frequencies in both irradiated and non-irradiated bystander regions after different doses (0.2, 1 and 10 cGy) of alpha-particle irradiation. Treatment with c-PTIO, a nitric oxide (NO) scavenger, the induced fractions of MN frequencies were dramatically inhibited both in 1 cGy alpha-particle irradiated and non-irradiated bystander regions with or without myosmine treatment. Moreover, 1mM myosmine treatment distinctly enhanced gamma-H2AX foci formation in both 1 cGy alpha-particle irradiated and non-irradiated bystander regions. These data indicated that myosmine effectively enhanced the low dose alpha-particle-induced DNA damage in both irradiated and non-irradiated bystander regions and nitric oxide played a very important role in such process. PMID:19007910

Jiang, Erkang; Zhu, Lingyan; Zhao, Ye; Zhao, Guoping; Bao, Linzhi; Chen, Shaopeng; Yang, Gen; Wang, Jun; Xu, An; Wu, Lijun

2009-01-01

389

Heat profiles of laser-irradiated nails  

NASA Astrophysics Data System (ADS)

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 112.4C, 980 nm: 45.8 to 53.5C), as well as the elevation of average temperatures (808 nm: 29.5 to 38.2C, 980 nm: 27.1 to 32.6C) 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.

Paasch, Uwe; Nenoff, Pietro; Seitz, Anna-Theresa; Wagner, Justinus A.; Kendler, Michael; Simon, Jan C.; Grunewald, Sonja

2014-01-01

390

Phase transformations in neutron-irradiated Zircaloys  

SciTech Connect

Microstructural evolution in Zircaloy-2 and -4 spent-fuel cladding specimens after approx.3 years of irradiation in commercial power reactors has been investigated by TEM and HVEM. Two kinds of precipitates induced by the fast-neutron irradiation in the reactors have been identified, i.e., Zr/sub 3/O and cubic-ZrO/sub 2/ particles approximately 2 to 10 nm in size. By means of a weak-beam dark-field ''2-1/2D-microscopy'' technique, the bulk nature of the precipitates and the surficial nature of artifact oxide and hydride phases could be discerned. The Zr(Fe/sub x/,Cr/sub 1-x/)/sub 2/ and Zr/sub 2/(Fe/sub x/,Ni/sub 1-x/) intermetallic precipitates normally present in the as-fabricated material virtually dissolved in the spent-fuel cladding specimens after a fast-neutron fluence of approx.4 x 10/sup 21/ ncm/sup -2/ in the power reactors. The observed radiation-induced phase transformations are compared with predictions based on the currently available understanding of the alloy characteristics. 29 refs.

Chung, H.M.

1986-04-01

391

LISIRD: LASP Interactive Solar Irradiance Data Center  

NASA Astrophysics Data System (ADS)

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.

Lindholm, D. M.; Wilson, A.

2013-12-01

392

Irradiated microstructure of alloy 800H  

NASA Astrophysics Data System (ADS)

Austenitic alloy 800H has the same basic composition as INCOLOY alloy 800 (Fe-20Cr-32Ni) but with significantly higher creep-rupture strength due to a required 60 ?m minimum grain size. It is one of the high temperature candidate alloys being considered for Generation IV nuclear reactor systems. The radiation resistance of 800H has not been previously studied. This work provides information on the microstructural changes in 800H after irradiation using 5.0 MeV Ni ions at 500 C to 5 and 50 dpa. Following irradiation, changes in microstructure and phase stability were studied using transmission electron microscopy (TEM). At a dose of 50 dpa, no voids were found and the density and size of the faulted loops were measured to be 2.3 10 16 cm -3 and 8.4 nm, respectively. There are fine precipitates distributed in 800H with an average size approximately 6 nm and a density greater than 9.1 10 15 cm -3. The high Ni content and the presence of precipitates are believed to be responsible for the resistance to void formation at dose up to 50 dpa.

Gan, J.; Cole, J. I.; Allen, T. R.; Shutthanandan, S.; Thevuthasan, S.

2006-06-01

393

Irradiated microstructure of alloy 800H.  

SciTech Connect

Austenitic alloy 800H has the same basic composition as INCOLOY alloy 800 (Fe-20Cr-32Ni) but with significantly higher creep-rupture strength due to a required 60 {micro}m minimum grain size. It is one of the high temperature candidate alloys being considered for Generation IV nuclear reactor systems. The radiation resistance of 800H has not been previously studied. This work provides information on the microstructural changes in 800H after irradiation using 5.0 MeV Ni ions at 500 C to 5 and 50 dpa. Following irradiation, changes in microstructure and phase stability were studied using transmission electron microscopy (TEM). At a dose of 50 dpa, no voids were found and the density and size of the faulted loops were measured to be 2.3 x 10{sup 16} cm{sup -3} and 8.4 nm, respectively. There are fine precipitates distributed in 800H with an average size approximately 6 nm and a density greater than 9.1 x 10{sup 15} cm{sup -3}. The high Ni content and the presence of precipitates are believed to be responsible for the resistance to void formation at dose up to 50 dpa.

Gan, J.; Cole, J. I.; Allen, T. R.; Shutthanandan, S.; Thevuthasan, S.; Nuclear Technology; Univ. of Wisconsin; PNNL

2006-01-01

394

Irradiated microstructure of alloy 800H  

SciTech Connect

Austenitic alloy 800H has the same basic composition as INCOLOY alloy 800 (Fe?20Cr?32Ni) but with significantly higher creep-rupture strength due to a required 60 lm minimum grain size. It is one of the high temperature candidate alloys being considered for Generation IV nuclear reactor systems. The radiation resistance of 800H has not been previously studied. This work provides information on the microstructural changes in 800H after irradiation using 5.0 MeV Ni ions at 500 *C to 5 and 50 dpa. Following irradiation, changes in microstructure and phase stability were studied using transmission electron microscopy (TEM). At a dose of 50 dpa, no voids were found and the density and size of the faulted loops were measured to be 2.3 ? 1016 cm*3 and 8.4 nm, respectively. There are fine precipitates distributed in 800H with an average size approximately 6 nm and a density greater than 9.1 ? 1015 cm*3. The high Ni content and the presence of precipitates are believed to be responsible for the resistance to void formation at dose up to 50 dpa.

Gan, Jian; Cole, J I.; Allen, T. R.; Shutthanandan, V; Thevuthasan, Suntharampillai

2006-06-01

395

Properties of polymers after cryogenic neutron irradiation  

NASA Astrophysics Data System (ADS)

Organic matrix insulation has been specified for use in fusion reactor superconducting coils due to lower material and fabrication costs compared to other forms of insulation. Glass fabric filled resins are prime candidates since they provide not only electrical insulation, but also the mechanical strength necessary to withstand the high magnetic forces present during coil operation. Two epoxy- and two polyimide-based fiber reinforced materials were irradiated to neutron fluences of 4.1 10 21n/m 2, E > 0.1 MeV at 4.2 K. Post-irradiation testing included flexural (3 pt. bend), as well as DC conductivity and dielectric breakdown strength. Measurements were made at 77 K and 300 K. Flexural strength was observed to decrease for the epoxy-based materials while the polyimide-based materials exhibited essentially no change in strength. Both DC conductivity and dielectric breakdown strength revealed little or no pattern of degradation at all levels of radiation exposure.

Tucker, D. S.; Clinard, F. W.; Hurley, G. F.; Fowler, J. D.

1985-08-01

396

Vaporization of perfluorocarbon droplets using optical irradiation  

PubMed Central

Micron-sized liquid perfluorocarbon (PFC) droplets are currently being investigated as activatable agents for medical imaging and cancer therapy. After injection into the bloodstream, superheated PFC droplets can be vaporized to a gas phase for ultrasound imaging, or for cancer therapy via targeted drug delivery and vessel occlusion. Droplet vaporization has been previously demonstrated using acoustic methods. We propose using laser irradiation as a means to induce PFC droplet vaporization using a method we term optical droplet vaporization (ODV). In order to facilitate ODV of PFC droplets which have negligible absorption in the infrared spectrum, optical absorbing nanoparticles were incorporated into the droplet. In this study, micron-sized PFC droplets loaded with silica-coated lead sulfide (PbS) nanoparticles were evaluated using a 1064 nm laser and ultra-high frequency photoacoustic ultrasound (at 200 and 375 MHz). The photoacoustic response was proportional to nanoparticle loading and successful optical droplet vaporization of individual PFC droplets was confirmed using photoacoustic, acoustic, and optical measurements. A minimum laser fluence of 1.4 J/cm2 was required to vaporize the droplets. The vaporization of PFC droplets via laser irradiation can lead to the activation of PFC agents in tissues previously not accessible using standard ultrasound-based techniques. PMID:21698007

Strohm, Eric; Rui, Min; Gorelikov, Ivan; Matsuura, Naomi; Kolios, Michael

2011-01-01

397

Phytosanitary irradiation of Liriomyza trifolii (Diptera: Agromyzidae).  

PubMed

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

Hallman, Guy J; Guo, Kun; Liu, Tong-Xian

2011-12-01

398

Degradation of dibromophenols by UV irradiation.  

PubMed

We examined the degradation of dibromophenols (DBPs), i.e. 2,4-DBP, 2,6-DBP and 3,5-DBP by ultraviolet (UV) irradiation and estimated the relationship between degradability and molecular orbital properties of each dibromophenol. The removal of DBPs under a UV lamp system was successfully performed in an aqueous solution. After 5 min of irradiation, the initial DBPs concentration of 20 mg/L was decreased to below 1 mg/L, and about 60% of bromide ion was released. A decrease in the concentration of dissolved organic carbon (DOC) suggested the mineralization of DBPs. The mineralization may occur after release of bromide ions because the decrease of DOC was slower than the release of bromide ions. The degradability of 3,5-DBP was slightly lower than 2,6-DBP and 2,4-DBP. Molecular orbital calculation suggested that the electrophilic frontier density and the highest occupied molecular orbital (HOMO) energy may be related to the degradability of DBPs. PMID:25079837

Katayama-Hirayama, Keiko; Toda, Naoki; Tauchi, Akihiko; Fujioka, Atsushi; Akitsu, Tetsuya; Kaneko, Hidehiro; Hirayama, Kimiaki

2014-06-01

399

Evolution of defect cluster distributions during irradiation  

SciTech Connect

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.

Wiedersich, H.

1991-05-01

400

Current status and regulation of food irradiation  

SciTech Connect

It is estimated by the Food and Agricultural Organization (FAO) of the United Nations that 25 to 35 percent of world food production is lost through natural causes such a pests, microbes, and insects. In the ASEAN countries alone, postharvest losses of cereals are estimated at 30 percent, fruits and vegetables at 20 to 40 percent, and up to 50 percent for fish. Some products in Africa suffer postharvest losses as high as 50 percent. One of the best responses to the problem of world hunger is preservation of what has already been grown. If postharvest losses worldwide could be minimized, food supply gains could be made without allocation of additional resources. The problems of food production, processing and storage require a continuing search for effective, technically and economically feasible alternative methods of food preservation. Food irradiation is not a panacea for this problem, however. Alone, it cannot change conditions or solve the problems of world hunger, but it can become a factor in the improvement of conditions where improved human nutrition is an immediate need. Food irradiation has progressed steadily over the past 40 years in terms of research, development, and legislative or regulatory activities.

Sivinski, J.S.

1987-01-01

401

LWRS ATR Irradiation Testing Readiness Status  

SciTech Connect

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

Kristine Barrett

2012-09-01

402

Effects of X irradiation on angiogenesis  

SciTech Connect

We have evaluated the effect of X irradiation on the mesenchymal tissue growth (blood capillaries and stromal cells) in an angiogenesis system in the mouse. This was accomplished by implanting a polyvinyl alcohol sponge disc in the subcutis of the thorax, and quantifying the extent of growth reduction of capillaries and stromal cells following graded doses of X rays. The sponge disc contained a centrally located pellet impregnated with 20 micrograms of epidermal growth factor and coated with a thin film of slow-releasing compound. Total growth of vessels and fibroblasts was determined by morphometric analysis of histologic sections. The incorporation of ({sup 3}H)TdR was measured during a 24-h period. A dose-response relationship was observed when X irradiation was given on Day 11 after implantation, with the disc removed on Day 20. A single dose of 15 Gy reduced both the rate of incorporation of ({sup 3}H)TdR and the total growth area. These and previous observations point to endothelial cells as important targets of ionizing radiation in the stroma, especially during the period of active proliferation of these cells, induced by growth factors.

Prionas, S.D.; Kowalski, J.; Fajardo, L.F.; Kaplan, I.; Kwan, H.H.; Allison, A.C. (Stanford Univ. School of Medicine (USA))

1990-10-01

403

Hafnium radioisotope recovery from irradiated tantalum  

DOEpatents

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.

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

2001-01-01

404

Irradiation induced microstructural changes in Zr-Excel alloy  

NASA Astrophysics Data System (ADS)

The in situ ion irradiation technique has been employed to elucidate irradiation damage in the dual phase Zr-Excel alloy. 1 MeV Kr ion irradiation experiments were conducted at different temperatures ranging from 100 C to 400 C. Damage microstructures have been characterized by transmission electron microscopy in both the alpha (?) and beta (?) phases after a maximum dose of 10 dpa at different temperatures. Several important observations including low temperature -component loop formation, and irradiation induced omega (?) phase precipitation have been reported. In situ irradiation provided an opportunity to observe the nucleation and growth of basal plane -component loops and irradiation induced dissolution of secondary phase precipitates at the same time. It has been shown that under Kr ion irradiation the -component loops start to nucleate and grow above a threshold dose, as has been observed for neutron irradiation. Furthermore, the role of temperature, material composition and pre-irradiation microstructure has been discussed in detail. lt;c>-Component loops nucleate and grow above a threshold dose which has been recorded as 2.5 dpa at 400 C. These loops nucleate in the proximity of secondary phase precipitates and grow as the precipitates shrink due to irradiation induced dissolution. The size of -component loops increases, whereas defect number density decreases with an increase of irradiation temperature. There is a significant difference of the -component loops microstructure in the as-received and heat-treated materials. -component loops seem to be of much larger size in AR material and the density of these loops drops significantly compared to the HT material. Semi-denuded zones are formed at the grain boundaries of the ?-phase, which is attributed to the depletion of Fe on the grain boundary. omega;-Phase precipitation and growth happens at all irradiation temperatures. Aging experiments on unirradiated specimens confirm that at higher temperature there are combined effects from radiation damage and isothermal nucleation; whereas at lower temperature only radiation induced ?-phase formation occurs in the time scales studied. The volume fraction of ?-phase decreases with an increase of irradiation temperature and the precipitate size increases with an increase of irradiation temperature, however in unirradiated material both volume fraction and precipitate size increase with an increase in temperature. This study can be implicated to improve the design of generation IV CANDU-SCWR. Low temperature formation of -component loops and ?-phase precipitation are striking results signifying potential irradiation growth and resultant changes in the mechanical properties of CANDU-SCWR fuel channel designs.

Idrees, Y.; Yao, Z.; Sattari, M.; Kirk, M. A.; Daymond, M. R.

2013-10-01

405

MeV Proton Irradiation Effects on Fullerenes and Graphite  

SciTech Connect

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.

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

406

27Solar Irradiance Changes and the Sunspot Cycle Irradiance (also called insolation) is a measure of the amount of sunlight power  

E-print Network

27Solar Irradiance Changes and the Sunspot Cycle Irradiance (also called insolation) is a measure the solar irradiance and sunspot number since January 1979 according to NOAA's National Geophysical Data climate. The solar irradiance data obtained by the ACRIM satellite, measures the total number of watts

407

Thermal release of volatile fission products from irradiated nuclear fuel  

Microsoft Academic Search

An effective procedure for removing H, Xe and Kr from irradiated fuels was demonstrated using Shippingport UO fuel. The release characteristics of H, Kr, Xe, and I from irradiated nuclear fuel have been determined as a function of temperature and gaseous environment. Vacuum outgassing and a flowing gas stream have been used to vary the gaseous environment. Vacuum outgassing released

L. A. Bray; L. L. Burger; L. G. Morgan; D. L. Baldwin

2011-01-01

408

RETAIL MEAT MANAGERS' PROFITABILITY EXPECTATIONS FOR IRRADIATED RED MEATS  

Microsoft Academic Search

This paper uses data from 40 personal interviews with meat department managers at grocery stores and supermarkets to investigate managers' expectations regarding the profitability potential of irradiated red meats. The study models managers' profitability expectations as function of many attributes and factors, such as the meat manager's or store's characteristics, how familiar the meat manager is with irradiation, and opinions

Joe Gaynor; Kimberly L. Jensen; Edward C. Jaenicke

2002-01-01

409

Recurrence plots of sunspots, solar flux and irradiance  

Microsoft Academic Search

The paper shows the recurrence and cross recurrence plots of three time series, concerning data of the solar activity. The data are the sunspot number and the values of solar radio flux at 10.7 cm and of solar total irradiance, which are known as highly correlated. To compare the series, the radio flux and irradiance values are monthly averaged. Recurrence

Amelia Sparavigna

2008-01-01

410

Partial Breast Irradiation after Breast-Conserving Surgery  

Microsoft Academic Search

Background: The standard technique of postoperative radiotherapy after breast-conserving surgery is percutaneous irradiation of the entire breast to a total dose of 4550 Gy which is usually followed by a tumor bed boost. Since the majority of local recurrencesin selected patients occur close to the former tumor bed, the question arises whether a sole tumor bed irradiation might be a

Georg Sauer; Vratislav Strnad; Christian Kurzeder; Rolf Kreienberg; Rolf Sauer

2005-01-01

411

Influence of ionizing irradiation on the properties of thermoelectric coolers  

NASA Astrophysics Data System (ADS)

Influence of ionizing irradiation of different kinds on the thermoelectrical parameters of the thermoelements on the base of Bi2Te3-Bi2Se3 and Bi2Te3- Sb2Te3 systems solid solutions have been investigated. To ascertain the mechanism of the action of irradiation on thermoelectrical parameters of TEC, previously the influence of this irradiation on the properties of crystals also was studied. The samples investigated were obtained by the oriented crystallization method--Bridgman technique and subjected to action of gamma- irradiation in the range of fluences 106 - 108 R, electron irradiance of 25 MeV energy in fluence range 1013 - 1014 cm-2 and pulse gamma-neutron irradiation in fluence range 1013 - 1014 cm-2. It is shown that irradiation by gamma-neutrons up to fluences 1014 cm-2 leads to increasing of (Delta) Tmax of TEM, as well as efficiency of n- and p- branches of thermoelements. This fact permits to suppose, that such a variations of (Delta) Tmax are due both to decreasing of resistance of transitional contacts and increasing of thermoelectric figure of merit of the thermoelectric material itself. Thus results obtained are indicated that variations of (Delta) Tmax for TEM under irradiation are due both to variations of thermoelement branches parameters and the resistance of transitional contacts.

Askerov, K. A.

1999-06-01

412

The Radiological Accident at the Irradiation Facility in Nesvizh  

Microsoft Academic Search

On 26 October 1991 at an industrial sterilisation facility in Nesvizh, Belarus, an operator entered the irradiation chamber and was exposed to a lethal dose of radiation. This publication, the third to be issued by IAEA on irradiator accidents, describes the events leading up to the accident, the dose received by the operator, the subsequent medical management and the lessons

Richard Paynter

1998-01-01

413

US RERTR FUEL DEVELOPMENT POST IRRADIATION EXAMINATION RESULTS  

Microsoft Academic Search

Post irradiation examinations of irradiated RERTR plate type fuel at the Idaho National Laboratory have led to in depth characterization of fuel behavior and performance. Both destructive and non-destructive examination capabilities at the Hot Fuels Examination Facility (HFEF) as well as recent results obtained are discussed herein. New equipment as well as more advanced techniques are also being developed to

A. B. Robinson; D. M. Wachs; D. E. Burkes; D. D. Keiser

2008-01-01

414

Proton Irradiation Damage Assessment of Carbon Reinforced Composites  

E-print Network

" orientation Irradiation exposure of different specimens shown in mCi #12;How well is our nanometer-irradiation (annealing) behavior !!! 2.70 mCi 7.62 mCi 8.08 mCi 4.62 mCi #12;DILEMMA Is it just the 2D carbon composite

McDonald, Kirk

415

Improved field emission of electrons from ion irradiated carbon  

Microsoft Academic Search

Electron field emission from allotropes of carbon (graphite, diamondlike carbon, and diamond) have been reported many times in the literature. This work explores the use of ion irradiation for improving electron field emission from carbon fibers. Carbon fibers have been irradiated with H, C, Ar, and Xe ions. Field emission characteristics have been measured as a function of ion dose.

K. C. Walter; H. H. Kung; C. J. Maggiore

1997-01-01

416

PARAMAGNETIC RESONANCE ABSORPTION OF GAMMA IRRADIATED SYNTHETIC ZEOLITES  

Microsoft Academic Search

The effect of gamma irradiation of synthetic zeolites was studied. ; Sodium X and sodium Y zeolites and also decationated samples prepared from these ; were irradiated in vacuum at room temperature with doses up to 20 megaroentgens. ; Two types of EPR signals were obtained. For the sodium Y and the sodium X ; zeolite a single line signal

D. N. Stamires; J. Turkevich

1963-01-01

417

Radiation retinopathy after orbital irradiation for Graves' ophthalmopathy  

Microsoft Academic Search

Recent reports indicate that orbital irradiation for Graves' ophthalmopathy is sometimes beneficial, particularly for dysthyroid optic neuropathy, and is not associated with serious complications. We are aware, however, of four patients who were found to have radiation retinopathy after orbital irradiation for Grave's ophthalmopathy. All four patients have decreased central acuity, and three of the four are legally blind in

J. L. Kinyoun; R. E. Kalina; S. A. Brower; R. P. Mills; R. H. Johnson

1984-01-01

418

Backscattering measuring system for optimization of intravenous laser irradiation dose  

NASA Astrophysics Data System (ADS)

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.

Rusina, Tatyana V.; Popov, V. D.; Melnik, Ivan S.; Dets, Sergiy M.

1996-11-01

419

Colloidal assemblies modied by ion irradiation E. Snoeks a  

E-print Network

. The 290 nm and 1.1 lm diameter colloids were deposited on a Si substrate and irradiated at 90 K, using for thin-®lm deposition, and in tuning the optical properties of three-dimensional colloidal crystals. ?Colloidal assemblies modi®ed by ion irradiation E. Snoeks a , A. van Blaaderen a,b , T. van Dillen

Polman, Albert

420

Induction of overproducing alkaline protease Bacillus mutants through UV irradiation  

Microsoft Academic Search

Bacillus pumilus and Bacillus alvei, among alkaline protease producing strains, were used to examine the changes in alkaline protease gene expression following UV irradiation. Induction of mutation in Bacillus mutant strains was carried out by 0, 5, 10, 15 and 20 min. exposure times of UV irradiation and different distances between the treated bacterial cultures and UV source. Results revealed

E. A. M. Solaiman; Wafaa K. Hegazy; Maysa E. Moharam

421

Prolonged Survival of Vascularized Limb Tissue Allografts by Donor Irradiation  

Microsoft Academic Search

The clinical feasibility of transplantation of a vascularized limb tissue allograft depends upon reducing immunosuppression and its associated toxicity for the graft recipient. Donor or allograft irradiation would eradicate allogeneic marrow and provide a possible alternative or beneficial addition to host immunosuppression. The effect of irradiation on survival of limb tissue allograft was investigated in this study. In a rat

W. P. Andrew Lee; Mark A. Randolph; Andrew J. Weiland; Michael J. Yaremchuk

1995-01-01

422

Potential chemical markers for the identification of irradiated sausages.  

PubMed

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

Kwon, Joong Ho; Akram, Kashif; Nam, Ki Chang; Min, Byungrok; Lee, Eun Joo; Ahn, Dong U

2012-09-01

423

Luminescence properties of silver zinc phosphate glasses following different irradiations  

Microsoft Academic Search

We report on exposing a photosensitive zinc phosphate glass containing silver to different radiation (electron, gamma, optical). Laser irradiations using nanosecond ultraviolet (UV) and femtosecond infrared (IR) laser are compared with gamma and electron exposure. All irradiated glasses exhibit absorption maxima around 320nm and 380nm and emission in the visible spectral range. Following exposure, silver clusters are formed. The optical

C. Maurel; T. Cardinal; M. Bellec; L. Canioni; B. Bousquet; M. Treguer; J. J. Videau; J. Choi; M. Richardson

2009-01-01

424

Reflected and Transmitted Irradiance from Area Sources using Vertex Tracing  

E-print Network

illumi- nation from perfectly reflective facets and through refractive objects. For the reflective the approach can be extended to handle reflected irradiance, while Section 4 develops the refraction heuristicReflected and Transmitted Irradiance from Area Sources using Vertex Tracing Michael M. Stark

Utah, University of

425

Retention of Hydrogen Isotopes in Neutron Irradiated Tungsten  

SciTech Connect

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 m 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.

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

426

Cobra-1A copper irradiation experiment in EBR-II  

SciTech Connect

The objective of this effort is to provide data on the radiation response of copper alloys selected as candidates for divertor service in ITER and other fusion devices. Specimen preparation for copper alloys to be irradiated in EBR-II Run 162 in the COBRA irradiation vehicle is complete. Specimens include TEM disks, miniature tensile and miniature fatigue specimens.

Garner, F.A; Hamilton, M.L., [Pacific Northwest Lab., Richland, VA (United States)

1992-12-31

427

SURVEILLANCE OF PHOTOVOLTAIC SOLAR ENERGY SYSTEMS USING METEOSAT DERIVED IRRADIANCES  

E-print Network

SURVEILLANCE OF PHOTOVOLTAIC SOLAR ENERGY SYSTEMS USING METEOSAT DERIVED IRRADIANCES Annette Hammer of a year offering 90 % of the annual solar irradiation. 1 INTRODUCTION Photovoltaic (PV) Systems generate. These checks are done by calculating the estimated output of the PV system with a simulation-model. The model

Heinemann, Detlev

428

Facilities for studing radiation damage in nonmetals during irradiation  

NASA Astrophysics Data System (ADS)

Two facilities were developed for making optical absorption, luminescence and other measurements on a single sample before, during and after irradiation. One facility uses Co-60 gamma rays and the other 0.5 to 3 MeV electrons from an accelerator. Optical relays function as spectrophotometers, luminescence detectors, etc. All radiation sensitive components are outside of walk-in irradiation chambers; all measurement control and data recording is computerized. Irradiations are made at controlled temperatures between 5 K and 900 C. The materials studied include glasses, quartz, alkali halides (especially natural rock salt), organic crystals, etc. As determined from color center measurements the damage formation rate in all materials studied at 25 C or above is strongly temperature dependent. The defect concentration during irradiation is usually much greater than that measured after irradiation. The fraction of defects annealing after irradiation and the annealing rate usually increases as the irradiation temperature increases. The completed studies demonstrate that, in most cases, the extent of maximum damage and the damage formation and annealing kinetics can be determined only by making measurements during irradiation.

Levy, P. W.

1984-08-01

429

The future of irradiation applications on Earth and in space  

NASA Technical Reports Server (NTRS)

What needs to be done to establish food irradiation on a truly commercial basis so that those living on planet Earth can fully realize the benefits of this versatile process? This question is answered in the first part of this paper. The second part covers the potential contributions of irradiated foods to feed humans in space.

Karel, M.

1989-01-01

430

Noise-induced local heatings in beam irradiation  

Microsoft Academic Search

In every kind of beam irradiation, a part of the incident power is eventually dissipated within the irradiated sample, leading to a heating which has to be evaluated, in order to be sure that thermal effects (such as diffusion, phase transitions, etc.) are under control. Expanding on usual thermal estimations based upon the coherent part of the incident power, we

G. Plumereau; P. Aranda; P. Ailloud; P. Berger; D. Boutard; F. Ladieu

1999-01-01

431

Variations in total solar irradiance during solar cycle 22  

Microsoft Academic Search

In this study, we have attempted to model the variations in total solar irradiance from two spacecraft. Specifically, we have modeled the Earth Radiation Budget on the Nimbus 7 spacecraft and the active cavity radiometer irradiance monitor (ACRIM-I) on the Solar Maximum Mission (SMM) spacecraft using ground-based photometry of sunspots and faculae from the San Fernando Observatory (SFO). Additionally, for

G. A. Chapman; A. M. Cookson; J. J. Dobias

1996-01-01

432

A reconstruction of total solar irradiance since 1700  

Microsoft Academic Search

The irradiance of the Sun is reconstructed from 1700 to the present, whereby the contributions of active regions and the quiet Sun are modelled separately. A method is proposed which allows the contribution of active-region faculae and sunspots to irradiance changes to be isolated even when only a single proxy of solar activity, such as sunspot relative number, RZ is

S. K. Solanki; M. Fligge

1999-01-01

433

A discussion of plausible solar irradiance variations, 1700-1992  

Microsoft Academic Search

From satellite observations the solar total irradiance is known to vary. Sunspot blocking, facular emission, and network emission are three identified causes for the variations. In this paper we examine several different solar indices measured over the past century that are potential proxy measures for the Sun's irradiance. These indices are (1) the equatorial solar rotation rate, (2) the sunspot

Douglas V. Hoyt; Kenneth H. Schatten

1993-01-01

434

Measurements of solar total irradiance and its variability  

Microsoft Academic Search

The development of electrically self calibrated cavity pyrheliometric instrumentation that occurred in the early 20th century provided the technological base for experiments to detect variability of the solar total irradiance. Experiments from ground based observatories, aircraft and balloons during the 1st half of the 20th century were unable to achieve sufficient accuracy or long term precision to unambiguously detect irradiance

Richard C. Willson

1984-01-01

435

Long-term downward trend in total solar irradiance  

Microsoft Academic Search

The first 5 years (from 1980 to 1985) of total solar irradiance observations by the first Active Cavity Radiometer Irradiance Monitor (ACRIM I) experiment on board the Solar Maximum Mission spacecraft show a clearly defined downward trends of -0.019% per year. The existence of this trend has been confirmed by the internal self-calibrations of ACRIM I, by independent measurements from

R. C. Willson; H. S. Hudson; C. Frohlich; R. W. Brusa

1986-01-01

436

Fuzzy algorithm for estimation of solar irradiation from sunshine duration  

Microsoft Academic Search

Solar irradiation and sunshine duration are intimately related phenomena and a model involving the relationship between them can best be derived by methods that explicitly take vagueness into account. In this paper, the theory of fuzzy sets, especially fuzzy modeling, is employed to represent solar irradiation and sunshine duration relations as a set of fuzzy rules. A fuzzy logic algorithm

Zekai ?en

1998-01-01

437

Application of Singular Spectrum Analysis to Solar Irradiance Variability  

NASA Technical Reports Server (NTRS)

Studies of solar variability improve our knowledge of the internal structure and dynamical processes taking place within the Sun that lead to solar irradiance changes. Becuase of the astrophysical and climatic significance of irradiance variability, considerable effort has been devoted to model and understand its physical origin.

Pap, Judit M.; Varadi, Ferenc

1995-01-01

438

Susceptibility of irradiated bovine aortic endothelial cells to injury  

SciTech Connect

Using cultured bovine aortic endothelial cells (BAEC), the authors attempted to determine whether prior irradiation would alter the susceptibility of these cells to three known injurious stimuli and, if so, whether the alteration would be related to radiation dose. BAEC were irradiated with 0, 5, or 10 Gy of gamma rays and, on the third postirradiation day, exposed to fibrin, nicotine, or bacterial endotoxin (lipopolysaccharide, LPS). Release of prelabeled 51Cr, representing cell lysis, cell detachment, or a combination of the two, was determined. Significant differences between irradiated and control cells were determined by using paired Student's t-tests. Irradiation did not appear to have altered the sensitivity of BAEC to fibrin-induced injury. Cells irradiated with 10 Gy of gamma rays, but generally not those irradiated with half this dose, showed a heightened susceptibility to nicotine. Contrary to the nicotine results, irradiated cells showed less cell detachment and lysis after exposure to LPS. These results suggest that the susceptibility of irradiated BAEC to harmful stimuli depends largely on the nature of the stimulus as well as the radiation dose.

Zhou, M.H.; Dong, Q.; Ts'ao, C.

1988-11-01

439

Radiation Induced Coloring of Glasses Measured During and after Electron Irradiation.  

National Technical Information Service (NTIS)

The growth of color centers during irradiation, and the decay after irradiation, were studied in two glasses using recently developed equipment for making optical absorption and luminescence measurements during and after electron irradiation. The glasses ...

K. J. Swyler, W. H. Hardy, P. W. Levy

1975-01-01

440

76 FR 5102 - Draft NUREG-0561, Revision 2; Physical Protection of Shipments of Irradiated Reactor Fuel...  

Federal Register 2010, 2011, 2012, 2013

...Protection of Shipments of Irradiated Reactor Fuel; Extension of Comment Period AGENCY...pertaining to the transport of irradiated reactor fuel (for purposes of this rulemaking, the terms ``irradiated reactor fuel'' and ``spent nuclear...

2011-01-28

441

Health Risk Assessment of Irradiated Topaz  

NASA Astrophysics Data System (ADS)

Radiation-produced blue topaz, indistinguishable from natural blue topaz, is produced by several different techniques. Published information on radionuclides present, activity levels, equipment necessary to detect activated nuclides and dosimetric assessment is lacking. Using a 60 megawatt nuclear reactor, fifty-one samples of colorless topaz from Nigeria, Sri Lanka, India and Brazil were irradiated with thermal and fast neutron fluences ranging from 1.8 times 10 13 to 9.2 times 1018 neutrons cm^{-2}. Seventeen MeV electrons produced by a linear accelerator were also used to irradiate 36 colorless topaz from the same countries. Gamma ray or positron-emitting nuclides were identified using calibrated well-type NaI or germanium detectors. For germanium detectors having relative efficiencies of approximately 20 percent, an analysis time of one hour or more was needed. Geiger Mueller (G-M) detectors, scintillators (plastic and liquid), gas flow proportional counters, a ZnS detector and autoradiography techniques were used to measure charged particle activity. Isotopes produced from neutron activation included 182Ta, ^ {59}Fe, 46Sc, 51Cr, 54Mn, 124Sb, ^{32 }P, 77As, ^ {183}Ta, 77Ge, 72Ga, and ^{24 }Na. Possible nuclides produced from 17 MeV electron treatment include ^{68 }Ga, 64Cu, ^ {49}Cr, and 18F. Positive identification of the electron activated nuclides was not possible because of the short half-lives involved (<1 day). Of the possible pure beta emitters activated during neutron bombardment, 32P and 35S are the most likely to be produced. The identification of 32P was made using a three point beta absorption analysis with a G-M detector. Skin and breast cancer risk estimates were calculated for various sized topaz containing NRC exempt concentration levels. When compared to a negligible individual risk level (NIRL) of 10^{-7}, the risk of an irradiated topaz in contact with the skin or three inches from breast tissue was a small fraction of the NIRL. At a risk level of 10^{ -7}, nuclides identified in topaz with a table facet area of greater than approximately 0.5 cm ^2 can be detected at twice background levels using a shielded G-M detector having a window thickness of 1.4 to 2.0 mg cm^{-2}.

Nelson, Kevin Lyle

1991-06-01

442

ACL reconstruction with BPTB autograft and irradiated fresh frozen allograft*  

PubMed Central

Objective: To analyze the clinical outcomes of arthroscopic anterior cruciate ligament (ACL) reconstruction with irradiated bone-patellar tendon-bone (BPTB) allograft compared with non-irradiated allograft and autograft. Methods: All BPTB allografts were obtained from a single tissue bank and the irradiated allografts were sterilized with 2.5 mrad of irradiation prior to distribution. A total of 68 patients undergoing arthroscopic ACL reconstruction were prospectively randomized consecutively into one of the two groups (autograft and irradiated allograft groups). The same surgical technique was used in all operations done by the same senior surgeon. Before surgery and at the average of 31 months of follow-up (ranging from 24 to 47 months), patients were evaluated by the same observer according to objective and subjective clinical evaluations. Results: Of these patients, 65 (autograft 33, irradiated allograft 32) were available for full evaluation. When the irradiated allograft group was compared to the autograft group at the 31-month follow-up by the Lachman test, the anterior drawer test (ADT), the pivot shift test, and KT-2000 arthrometer test, statistically significant differences were found. Most importantly, 87.8% of patients in the autograft group and just only 31.3% in the irradiated allograft group had a side-to-side difference of less than 3 mm according to KT-2000. The failure rate of the ACL reconstruction with irradiated allograft (34.4%) was higher than that with autograft (6.1%). The anterior and rotational stabilities decreased significantly in the irradiated allograft group. According to the overall International Knee Documentation Committee (IKDC), functional and subjective evaluations, and activity level testing, no statistically significant differences were found between the two groups. Besides, patients in the irradiated allograft group had a shorter operation time and a longer duration of postoperative fever. When the patients had a fever, the laboratory examinations of all patients were almost normal. Blood routine was normal, the values of erythrocyte sedimentation rate (ESR) were 5~16 mm/h and the contents of C reactive protein (CRP) were 3~10 mg/L. Conclusion: We conclude that the short term clinical outcomes of the ACL reconstruction with irradiated BPTB allograft were adversely affected. The less than satisfactory results led the senior authors to discontinue the use of irradiated BPTB allograft in ACL surgery and not to advocate using the gamma irradiation as a secondary sterilizing method. PMID:19353750

Sun, Kang; Tian, Shao-qi; Zhang, Ji-hua; Xia, Chang-suo; Zhang, Cai-long; Yu, Teng-bo

2009-01-01

443

Solar Spectral Irradiance variations: the long-term view  

NASA Astrophysics Data System (ADS)

Solar Spectral Irradiance variations: the long-term view S.K. Solanki Max Planck Institute for Solar System Research, Katlenburg-Lindau, Germany The total and spectral irradiance of the Sun are prime candidates for external forcing of the Earth's climate system. Whereas variations of total solar irradiance have been observed and modelled with great success, our corresponding knowledge of the variation of spectral irradi-ance is, by comparison, still in its infancy. Although, on short time-scales multiple measured time series and models are now available, on longer time-scales models are the only source of information. Until recently even the models were rather restricted, being either based purely on proxies, or limited in spectral range. A new generation of models is now available, which goes beyond the limitations of the earlier approaches. An overview of the models and their results is given, with the emphasis being placed on the most recent ones.

Solanki, Sami K.

444

The variability of the solar ultraviolet spectral irradiances  

NASA Technical Reports Server (NTRS)

Available data on the solar spectral irradiances at wavelengths below 3100 A are extremely limited and there are major uncertainties in many of the measurements. In particular, there is major disagreement on the magnitude of the variability of the spectral irradiances over the solar cycle. The effects of different solar features on the ultraviolet spectral irradiances over both the 28 day solar rotation period and over the solar cycle are discussed. It is proposed that any attempt to predict the magnitudes of the ultraviolet spectral irradiances must take into account a long term variability of emission from quiet regions of the solar disk over the solar cycle. The need for direct long term monitoring of the ultraviolet spectral irradiances is emphasized.

Timothy, J. G.

1979-01-01

445

Total lymphoid irradiation for treatment of intractable cardiac allograft rejection  

SciTech Connect

The ability of postoperative total lymphoid irradiation to reverse otherwise intractable cardiac allograft rejection was examined in a group of 10 patients in whom conventional rejection therapy (including pulsed steroids and monoclonal or polyclonal anti-T-cell antibody therapy) had failed to provide sustained freedom from rejection. Follow-up periods range from 73 to 1119 days since the start of total lymphoid irradiation. No patient died or sustained serious morbidity because of the irradiation. Three patients have had no further rejection (follow-up periods, 105 to 365 days). Two patients died--one in cardiogenic shock during the course of total lymphoid irradiation, the other with recurrent rejection caused by noncompliance with his medical regimen. Total lymphoid irradiation appears to be a safe and a moderately effective immunosuppressive modality for 'salvage' therapy of cardiac allograft rejection unresponsive to conventional therapy.

Hunt, S.A.; Strober, S.; Hoppe, R.T.; Stinson, E.B. (Stanford Univ.Medical Center, CA (USA))

1991-03-01

446

Esophageal ulceration induced by intracavitary irradiation for esophageal carcinoma  

SciTech Connect

Twenty-two patients with esophageal carcinoma had no local recurrence after external and intracavitary radiation treatment, but all developed ulcers in the field of intracavitary irradiation. Ten were linear ulcers that appeared 3-12 months after radiation treatment (mean, 5.3 months); the other 12 were the long circumferential type and appeared 1-8 months after irradiation (mean, 3.7 months). Esophagobronchial fistulae developed in two cases in which deep ulcer had been found between the completion of external irradiation and the beginning of intracavitary irradiation. In these cases with deep ulcer, intracavitary irradiation should not be done. For patients receiving intracavitary radiation, the total dosage should be less than 20 Gy.

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

1984-08-01

447

Tuning the electronic band structure of PCBM by electron irradiation  

PubMed Central

Tuning the electronic band structures such as band-edge position and bandgap of organic semiconductors is crucial to maximize the performance of organic photovoltaic devices. We present a simple yet effective electron irradiation approach to tune the band structure of [6, 6]-phenyl-C61-butyric acid methyl ester (PCBM) that is the most widely used organic acceptor material. We have found that the lowest unoccupied molecular orbital (LUMO) level of PCBM up-shifts toward the vacuum energy level, while the highest occupied molecular orbital (HOMO) level down-shifts when PCBM is electron-irradiated. The shift of the HOMO and the LUMO levels increases as the irradiated electron fluence increases. Accordingly, the band-edge position and the bandgap of PCBM can be controlled by adjusting the electron fluence. Characterization of electron-irradiated PCBM reveals that the variation of the band structure is attributed to the molecular structural change of PCBM by electron irradiation. PMID:21970617

2011-01-01

448

Intellectual, educational, and behavioural sequelae after cranial irradiation and chemotherapy.  

PubMed Central

Cognitive and educational sequelae are inconsistently reported in children treated with cranial irradiation for acute lymphoblastic leukaemia. This study investigated differences in these skills after cranial irradiation, controlling the effects of chemotherapy and psychosocial factors. Three groups were evaluated: 100 children diagnosed with acute lymphoblastic leukaemia and treated with cranial irradiation and chemotherapy; 50 children diagnosed with acute lymphoblastic leukaemia or other cancers and treated with chemotherapy alone; and a healthy control group of 100 children. Children in the clinical groups stopped treatment at least two years before evaluation and had no history of relapse. Children were aged between 7 and 16 at the time of assessment. Evaluation included cognitive, educational, and behavioural measures. Analyses found that children receiving cranial irradiation and chemotherapy performed more poorly than non-irradiated groups on intellectual and educational tests, with verbal and attentional deficits most pronounced. Children receiving chemotherapy alone performed similarly to controls, suggesting such treatment is not associated with adverse neurobehavioural sequelae. PMID:8048815

Anderson, V; Smibert, E; Ekert, H; Godber, T

1994-01-01

449

Automated detection of irradiated food with the comet assay.  

PubMed

Food irradiation is the process of exposing food to ionising radiation in order to disinfect, sanitise, sterilise and preserve food or to provide insect disinfestation. Irradiated food should be adequately labelled according to international and national guidelines. In many countries, there are furthermore restrictions to the product-specific maximal dose that can be administered. Therefore, there is a need for methods that allow detection of irradiated food, as well as for methods that provide a reliable dose estimate. In recent years, the comet assay was proposed as a simple, rapid and inexpensive method to fulfil these goals, but further research is required to explore the full potential of this method. In this paper we describe the use of an automated image analysing system to measure DNA comets which allow the discrimination between irradiated and non-irradiated food as well as the set-up of standard dose-response curves, and hence a sufficiently accurate dose estimation. PMID:17921509

Verbeek, F; Koppen, G; Schaeken, B; Verschaeve, L

2008-01-01

450

Tuning the electronic band structure of PCBM by electron irradiation.  

PubMed

Tuning the electronic band structures such as band-edge position and bandgap of organic semiconductors is crucial to maximize the performance of organic photovoltaic devices. We present a simple yet effective electron irradiation approach to tune the band structure of [6, 6]-phenyl-C61-butyric acid methyl ester (PCBM) that is the most widely used organic acceptor material. We have found that the lowest unoccupied molecular orbital (LUMO) level of PCBM up-shifts toward the vacuum energy level, while the highest occupied molecular orbital (HOMO) level down-shifts when PCBM is electron-irradiated. The shift of the HOMO and the LUMO levels increases as the irradiated electron fluence increases. Accordingly, the band-edge position and the bandgap of PCBM can be controlled by adjusting the electron fluence. Characterization of electron-irradiated PCBM reveals that the variation of the band structure is attributed to the molecular structural change of PCBM by electron irradiation. PMID:21970617

Yoo, Seung Hwa; Kum, Jong Min; Cho, Sung Oh

2011-01-01

451

Physical-chemical analyses of irradiated papayas ( Carica papaya L.)  

NASA Astrophysics Data System (ADS)

Papaya is cultivated in Esprito Santo State/Brazil and as it stands up to irradiation, it is important to validate this technology, since it is already being applied in some countries. Penetration energy, ratio (relation between soluble solids and titrable acidity) and skin color were evaluated to verify the influence of four different doses of irradiation (0.0, 0.5, 0.75 and 1.00 kGy) on papayas, during 21 days. As a result for the skin color and the penetration energy, it was found that in the first days after irradiation, these variables increased with increase in radiation dose; however, after a time lapse, the tendency inverted and the irradiated fruits had a slower ripening process. For the ratio, a very important variable that it is responsible for the fruit taste, no difference was found between irradiated and the control fruit. Color and texture measurements are dependent on the storage temperature.

Camargo, R. J.; Tadini, C. C.; Sabato, S. F.

2007-11-01

452

Leydig cell damage after testicular irradiation for lymphoblastic leukemia  

SciTech Connect

The effect of testicular irradiation on Leydig cell function has been studied in a group of boys irradiated between 1 and 5 years earlier for a testicular relapse of acute lymphoblastic leukemia. Six of the seven boys irradiated during prepubertal life had an absent testosterone response to HCG stimulation. Two of the four boys irradiated during puberty had an appropriate basal testosterone level, but the testosterone response to HCG stimulation was subnormal in three of the four. Abnormalities in gonadotropin secretion consistent with testicular damage were noted in nine of the 11 boys. Evidence of severe Leydig cell damage was present irrespective of whether the boys were studied within 1 year or between 3 and 5 years after irradiation, suggesting that recovery is unlikely. Androgen replacement therapy has been started in four boys and will be required by the majority of the remainder to undergo normal pubertal development.

Shalet, S.M.; Horner, A.; Ahmed, S.R.; Morris-Jones, P.H.

1985-01-01

453

Proton irradiation of germanium isotope multilayer structures at elevated temperatures  

NASA Astrophysics Data System (ADS)

Irradiation of germanium (Ge) isotope heterostructures with 2.5 MeV protons have been performed at 550 C. The applied proton flux was varied between 1.0 and 1.5 ?A leading to various rates of Frenkel pair production. After irradiation, concentration profiles of the Ge isotopes were recorded by means of secondary ion mass spectrometry (SIMS). An inhomogeneous broadening of the isotope structure was observed. In addition to the effect of irradiation enhanced self-diffusion, an influence of the formation of microscopic defects on the detected broadening was ascertained. Atomic force and scanning electron microscopy show that the microscopic defects are most probably resulting from an aggregation of vacancies formed during irradiation. Numerical analysis of Ge profiles not disturbed by microdefect formation indicates a significant contribution of self-interstitials to self-diffusion under irradiation.

Schneider, S.; Bracht, H.; Petersen, M. C.; Hansen, J. Lundsgaard; Larsen, A. Nylandsted

2008-02-01

454

Gamma ray irradiation for sludge solubilization and biological nitrogen removal  

NASA Astrophysics Data System (ADS)

This study was conducted to investigate the effects of gamma ray irradiation on the solubilization of waste sewage sludge. The recovery of an organic carbon source from sewage sludge by gamma ray irradiation was also studied. The gamma ray irradiation showed effective sludge solubilization efficiencies. Both soluble chemical oxygen demand (SCOD) and biochemical oxygen demand (BOD 5) increased by gamma ray irradiation. The feasibility of the solubilized sludge carbon source for a biological nitrogen removal was also investigated. A modified continuous bioreactor (MLE process) for a denitrification was operated for 20 days by using synthetic wastewater. It can be concluded that the gamma ray irradiation was useful for the solubilization of sludge and the recovery of carbon source from the waste sewage sludge for biological nitrogen removal.

Kim, Tak-Hyun; Lee, Myunjoo; Park, Chulhwan

2011-12-01

455

Isothermal decomposition of gamma-irradiated palladium acetate  

NASA Astrophysics Data System (ADS)

The isothermal decomposition of un-irradiated (pristine) and pre-gamma-irradiated palladium acetate was studied in the temperature range (498-508 K) and in air using the isothermal thermogravimetric technique. The data were analysed using various solid state reaction models. The results showed that the kinetics of isothermal decomposition of palladium acetate was governed by random nucleation reaction (Erofe'ev equation A(3)). The activation energies of the main decomposition process for un-irradiated and pre-gamma-irradiated samples were calculated. The change in texture and crystal structure of the investigated palladium acetate by gamma-irradiation was studied using electron microscopy and X-ray diffraction techniques.

Mahfouz, R. M.; Alshehri, S. M.; Monshi, M. A. S.; Abd El-Salam, N. M.

2004-06-01

456

Isothermal decomposition of gamma-irradiated dysprosium acetate  

NASA Astrophysics Data System (ADS)

Isothermal decomposition of un-irradiated and pre-gamma-irradiated dysprosium acetate [Dy(CH3COO)(3)] has been investigated at different temperatures between 603-623 K. Irradiation was observed to enhance the rate of decomposition without modifying the mechanism of the thermal decomposition. Thermal decomposition of dysposium acetate is shown to proceed by a nucleation and growth mechanism (Avarmi-Erofe'ev equation) both for un-irradiated and pre-gamma-irradiated samples. The enhancement of the decomposition was found to increase with an increase in the gamma-ray dose applied to the sample and may be attributed to an increase in point defects and formation of additional nucleation centers generated in the host lattice. Thermodynamic values of the main decomposition process were calculated and evaluated.

Mahfouz, R. M.; Al-Shehri, S. M.; Monshi, M. A. S.; Abd El-Salam, N. M.

457

Reconstructing the Solar VUV Irradiance Over the Past 60 Years  

NASA Technical Reports Server (NTRS)

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.

Chamberlin, Phillip C.

2011-01-01

458

Effects of UV-B irradiation on a marine microecosystem.  

PubMed

Purpose of this work was to study the effect of UV irradiation on a microecosystem consisting of several interacting species. The system chosen was of a hypersaline type, where all the species present live at high salt concentration; it comprises different bacteria; a producer, the photosynthetic green alga Dunaliella salina; and a consumer, the ciliated protozoan Fabrea salina, which form a complete food chain. We were able to establish the initial conditions that give rise to a self-sustaining microecosystem, stable for at least 3 weeks. We then determined the effect of UV irradiation on this microecosystem under laboratory-controlled conditions, in particular by measuring the critical UV exposure for the two main components of the microecosystem (algae and protozoa) under UV-B irradiances comparable to those of solar irradiation. In our experiments, we varied irradiance, total dose and spectral composition of the actinic light. The critical doses at irradiances of the order of 56 kJ/m(2) (typical average daily irradiance in a sunny summer day in Pisa), measured for each main component of the microecosystem (algae and ciliates), turned out to be around 70 kJ/m(2) for ciliates and 50 kJ/m(2) for D. salina. By exposing microecosystems to daily UV-B irradiances of the order of 8 kJ/m(2) (typical average daily irradiance in a sunny winter day in Pisa), we found no effect at total doses of the order of the critical doses at high irradiances, showing that the reciprocity law does not hold. We have also measured a preliminary spectral-sensitive curve of the UV effects, which shows an exponential decay with wavelength. PMID:15339218

Marangoni, Roberto; Messina, Nicola; Gioffr, Domenico; Colombetti, Giuliano

2004-01-01

459

Deformation mechanisms of irradiated metallic nanofoams  

NASA Astrophysics Data System (ADS)

It was recently proposed that within a particular window in the parameter space of temperature, ion energy, dose rate, and filament diameter, nanoscale metallic foams could show radiation tolerance [Bringa et al., Nano Lett. 12, 3351 (2012)]. Outside this window, damage appears in the form of vacancy-related stacking fault tetrahedra (SFT), with no effects due to interstitials [Fu et al., Appl. Phys. Lett. 101, 191607 (2012)]. These SFT could be natural sources of dislocations within the ligaments composing the foam and determine their mechanical response. We employ molecular dynamics simulations of cylindrical ligaments containing an SFT to obtain an atomic-level picture of their deformation behavior under compression. We find that plastic deformation originates at the edges of the SFT, at lower stress than needed to create dislocations at the surface. Our results predict that nanoscale foams soften under irradiation, a prediction not yet tested experimentally.

Zepeda-Ruiz, L. A.; Martinez, E.; Caro, M.; Fu, E. G.; Caro, A.

2013-07-01

460

Test results of heavily irradiated Si detectors  

NASA Astrophysics Data System (ADS)

A large use of silicon microstrip detectors is foreseen for the intermediate part of the CMS tracker. A specific research and development program has been carried out with the aim of finding design layouts and technological solutions for allowing silicon microstrip detectors to be reliably used on a high radiation level environment. As a result of this work single sided, AC-coupled, polysilicon biased, 300 ? m thick, p + on n substrate detectors were chosen. Irradiation tests have been performed on prototypes up to fluence 210 14 n/cm 2. The detector performances do not significantly change if the detectors are biased well above the depletion voltage. S/ N is reduced by less than 20%, still enough to insure a good efficiency and space resolution. Multiguard structures has been developed in order to reach high voltage operation (above 500 V).

Albergo, S.; Azzi, P.; Babucci, E.; Bacchetta, N.; Bader, A.; Bagliesi, G.; Bartalini, P.; Basti, A.; Biggeri, U.; Bilei, G. M.; Bisello, D.; Boemi, D.; Bosi, F.; Borrello, L.; Bozzi, C.; Breuker, H.; Bruzzi, M.; Candelori, A.; Caner, A.; Castaldi, R.; Castro, A.; Catacchini, E.; Checcucci, B.; Ciampolini, P.; Civinini, C.; Connotte, J.; Creanza, D.; D'Alessandro, R.; Da Rold, M.; de Palma, M.; Dell'Orso, R.; Della Marina, R.; Eklund, C.; Elliott-Peisert, A.; Feld, L.; Fiore, L.; Focardi, E.; French, M.; Freudenreich, K.; Giassi, A.; Giraldo, A.; Glessing, B.; Gu, W. H.; Hall, G.; Hammerstrom, R.; Hrubec, J.; Huhtinen, M.; Karimaki, V.; Krammer, M.; Lariccia, P.; Lenzi, M.; Loreti, M.; Luebelsmeyer, K.; Lustermann, W.; Maggi, G.; Mannelli, M.; Mantovani, G.; Marchioro, A.; Martignon, G.; Mc Evoy, B.; Meschini, M.; Messineo, A.; My, S.; Paccagnella, A.; Palla, F.; Pandoulas, D.; Parrini, G.; Passeri, D.; Pieri, M.; Piperov, S.; Potenza, R.; Raffaelli, F.; Raso, G.; Raymond, M.; Schmitt, B.; Selvaggi, G.; Servoli, L.; Sguazzoni, G.; Siedling, R.; Silvestris, L.; Skog, K.; Starodumov, A.; Stavitski, I.; Stefanini, G.; Tempesta, P.; Tonelli, G.; Tricomi, A.; Tuuva, T.; Vannini, C.; Verdini, P. G.; Viertel, G.; Xie, Z.; Wang, Y.; Watts, S.; Wittmer, B.

1999-02-01

461

Accuracy of delivered dose in pelvic irradiation  

SciTech Connect

The accuracy of dose delivered to the pelvis in patients undergoing radiation therapy for various pelvic malignancies was checked by the placement of thermoluminescent dosimeters (TLD) in either the rectum or the vagina. The probes were left in place for an entire treatment. Eighty-two measurements in 37 patients were evaluated. The ratio of the TLD measured dose to the calculated dose, D/sub TLD//D/sub calc/, was obtained for each measurement. A perfect match would give a ratio of 1.000. The average dose ratio for the measurements was 1.012, indicating an average accuracy of within 2%. No correlation could be shown between the dose radio and obesity or quantity of pelvic bowel gas. We conclude that pelvic irradiation can be delivered with good precision, and that TLD's are useful in monitoring treatment dose.

Graham, W.J.; Anderson, D.W.; Landry, D.J.

1981-08-01

462

CREEP STRAIN CORRELATION FOR IRRADIATED CLADDING  

SciTech Connect

In an attempt to predict the creep deformation of spent nuclear fuel cladding under the repository conditions, different correlations have been developed. One of them, which will be referred to as Murty's correlation in the following, and whose expression is given in Henningson (1998), was developed on the basis of experimental points related to unirradiated Zircaloy cladding (Henningson 1998, p. 56). The objective of this calculation is to adapt Murty's correlation to experimental points pertaining to irradiated Zircaloy cladding. The scope of the calculation is provided by the range of experimental parameters characterized by Zircaloy cladding temperature between 292 C and 420 C, hoop stress between 50 and 630 MPa, and test time extending to 8000 h. As for the burnup of the experimental samples, it ranges between 0.478 and 64 MWd/kgU (i.e., megawatt day per kilogram of uranium), but this is not a parameter of the adapted correlation.

P. Macheret

2001-01-23

463

Recovery of niobium from irradiated targets  

DOEpatents

A process for selective separation of niobium from proton irradiated molybdenum targets is provided and includes dissolving the molybdenum target in a hydrogen peroxide solution to form a first ion-containing solution, contacting the first ion-containing solution with a cationic resin whereby ions selected form the group consisting of molybdenum, biobium, technetium, selenium, vanadium, arsenic, germanium, zirconium and rubidium remain in a second ion-containing solution while ions selected from the group consisting of rubidium, zinc, beryllium, cobalt, iron, manganese, chromium, strontium, yttrium and zirconium are selectively adsorbed by the cationic resin; adjusting the pH of the second ion-containing solution to within a range of from about 5.0 to about 6.0; contacting the pH adjusting second ion-containing solution with a dextran-based material for a time to selectively separate niobium from the solution and recovering the niobium from the dextran-based material.

Phillips, Dennis R. (Los Alamos, NM); Jamriska, Sr., David J. (Los Alamos, NM); Hamilton, Virginia T. (Los Alamos, NM)

1994-01-01

464

Inactivation of Cryptosporidium parvum by ultrasonic irradiation.  

PubMed

The inactivation of Cryptosporidium parvum was investigated by the use of three different sonicators utilizing the squeeze-film effect, which may occur when ultrasound is irradiated into an extremely thin space and generate intensified pressure in the sample suspension. To expand from the small-scale horn-type sonicator to large-scale cylindrical or cleaning bath sonicators, the inactivation effectwas improved. In the case of the cylindrical sonicator (26.6 kHz, 30 W), 97% of the initial concentration of 2260 oocysts mL(-1) was inactivated at33 mL min(-1) (residence time of approximately 5.2 min). Hundreds of cubic meters of water can be treated per day at several kW using this sonicator. In addition, the simultaneous use of sonication and chlorination showed a beneficial effect on inactivation for C. parvum based on the evaluation of infectivity testing and morphological observation. PMID:16201661

Oyane, I; Furuta, M; Stavarache, C E; Hashiba, K; Mukai, S; Nakanishi, J M; Kimata, I; Maeda, Y

2005-09-15

465

Damage and repair of irradiated mammalian brain  

SciTech Connect

We have demonstrated that focal charged particle irradiation of the rabbit brain can create well-defined lesions which are observable by nuclear magnetic resonance imaging (NMR) and positron emission tomography (PET) imaging techniques. These are similar, in terms of location and characteristic NMR and PET features, to those that occur in the brain of about 10% of clinical research human subjects, who have been treated for intracranial vascular malformations with stereotactic radiosurgery. These lesions have been described radiologically as vasogenic e