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1

Le combustible nucléaire : contraintes de conception, évolutions sous irradiation et impacts sur la fin de cycle  

NASA Astrophysics Data System (ADS)

Nuclear fuel is the material in which the fission reactions occur. As such, it has to support many constraints induced by heat generation, fission product creation, as well as interaction with the coolant. These constraints are taken into account and fulfilled by the design. However, during irradiation, many changes are known to occur. Among them, irradiation damage, OD oxidation and changes in chemical or physical characteristics are to be considered. In addition, intermediate storage adds new constraints that the fuel has to support. With emphasis on the water reactor fuels, by far the most important group, a review will be given of major points, focusing on a few specific areas. To cite this article: C. Lemaignan, C. R. Physique 3 (2002) 763-772.

Lemaignan, Clément

2002-10-01

2

Hypertriglyc?rid?mie majeure sous tamoxif?ne  

PubMed Central

Plusieurs agents pharmacologiques sont incriminés dans les hyperlipidémies. Le tamoxifène fournit un exemple de médicament hypertriglycéridémiant. Nous décrivons ici le cas ?une patiente atteinte de cancer du sein traitée par tamoxifène qui a présenté une hypertriglycéridémie sévère. Nous présentons aussi une brève revue de la littérature et discutons les mécanismes sous jacents aux effets hypertriglycéridémiants du tamoxifène.

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

2012-01-01

3

Clostridium perfringens growth from spore inocula in sous-vide processed pork-based Mexican entrée.  

PubMed

The combined effect of Citricidal wih irradiation on Clostridium perfringens growth from spores in a sous-vide processed marinated pork meat Mexican entrée was investigated. Citricidal was added at 200 or 800 ppm after mixing pork meat with tomatillo sauce and inoculated with 3 log(10) CFU/g of C. perfringens spores. Samples were irradiated at either 0 or 2 kGy, heated to an internal temperature of 71 degrees C, and stored at 4 degrees C for 28 d, 15 degrees C for 45 d, and 25 degrees C for 26 h. To simulate the conditions that may occur during transportation, distribution, storage, or handling in supermarkets or by consumers, the effect of static temperature abuse on C. perfringens growth was assessed by transferring samples stored at 4 to 25 degrees C for 13 and 15 h. Total C. perfringens populations were determined by plating diluted samples on tryptose-sulfite-cycloserine agar. Growth was not observed up to 45 d of storage at 15 degrees C in samples supplemented with 800 ppm of Citricidal. At 25 degrees C, no significant differences (P > 0.05) on the lag phase duration due to antimicrobial treatments was observed. The temperature abuse of refrigerated products for up to 15 h did not lead to C. perfringens growth to high infective dose levels of 1 million cells required to cause food poisoning. The results suggest that 800 ppm Citricidal can have significant bacteriostatic activity against C. perfringens and may provide a degree of protection against this pathogen in sous-vide processed marinated pork meat Mexican entrée, under mild temperature abuse (

Miguel-Garcia, Denise Y; Juneja, Vijay K; Valenzuela-Melendrez, Martin; Díaz-Cinco, Martha E; Thippareddi, H; Aida Peña-Ramos, E

2009-01-01

4

Chômage et sous-emploi dans les DOM  

Microsoft Academic Search

[fre] Les problèmes d'emploi dans les départements d'outre-mer ne se limitent pas au chômage. Il faut y ajouter le sous-emploi, c'est-à-dire les faibles durées du travail de certains actifs, ou la perception de ressources insuffisantes.- Pour sa part, le chômage stricto sensu est très élevé dans les DOM : entre 25 et 30 % de la population active en Martinique,

Jean-Pierre Guengant; Hervé Domenach

1981-01-01

5

The effect of freezing compared with chilling on selected physico-chemical and sensory properties of sous vide cooked carrots  

Microsoft Academic Search

Sous vide is increasingly used to process convenience foods including ready-meals as it is reputed to give superior quality because of the mild process and the absence of oxygen in the pack. The potential for temperature abuse is greater for sous vide ready-meals than for sous vide catered items as the distribution and retailing chain for the former is usually

Fergal Tansey; Ronan Gormley; Francis Butler

2010-01-01

6

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

NASA Astrophysics Data System (ADS)

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

Bouchard, Alexandre

7

Photoconductivité et photoémission de diamant(s) sous irradiation XUV femtoseconde  

NASA Astrophysics Data System (ADS)

Nous décrivons une étude des propriétés de photoconductivité (PC) induite dans différents types de diamants (monocristaux de type IIa et couches CVD) par des impulsions femtosecondes XUV (jusqu'à l'harmonique 19 du laser titane/saphir). En complément de ces études, les spectres de photoémission de ces échantillons ont aussi été étudiés (harmoniques 13 à 27). En fonction de l'ordre de l'harmonique, on constate que le signal de PC augmente tout d'abord (harmoniques 9 à 13) puis diminue au delà. Si l'augmentation s'interprète aisément comme résultant de phénomènes de multiplication par collisions inélastiques, la diminution ultérieure n'a pas pour le moment d'explication. Les mesures de spectre de photoémission suggèrent un effet important de la relaxation par émission de plasmons. Enfin, nous avons réalisé le premier calcul ab-initio de la durée de vie des porteurs tenant compte des interactions électron-électron, à l'aide d'une approche de théorie quantique à plusieurs corps de type GW. Au voisinage du gap, on observe un comportement proche de celui d'un liquide de Fermi. A plus haute énergie on observe des déviations à ce comportement, provenant d'effets de structure de bande d'une part, et d'excitations de plasmons d'autre part.

Gaudin, J.; Geoffroy, G.; Guizard, S.; Esnouf, S.; Olevano, V.; Petite, G.; Klimentov, S. M.; Pivovarov, P. A.; Garnov, S. V.; Carre, B.; Martin, P.; Belsky, A.

2005-06-01

8

Detecteur optique de phase liquide dans un disjoncteur au SF6 sous pression  

NASA Astrophysics Data System (ADS)

In this paper, we present a device allowing us to detect gas-liquid or liquid-gas transition in an pressurized cell. This phase detector can be implemented in high voltage system. Dans cet article, on présente un dispositif permettant de détecter localement la transition liquide-gaz ou gaz-liquide dans une enceinte sous pression. Ce détecteur de phase peut etre installé dans des systèmes portés à potentiel élevé.

Buret, F.; Beroual, A.

1991-04-01

9

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

Microsoft Academic Search

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

Dominique Casin

2011-01-01

10

Observation d'un réseau de paraboles focales sous cisaillement dans un smectique A  

Microsoft Academic Search

On sait que, lorsqu'on dilate fortement un échantillon smectique homéotrope, à l'instabilité d'ondulation des couches succède la formation d'un treillis de paraboles focales. Nous montrons que ce même mécanisme subsiste sous cisaillement, l'effet de ce dernier étant de fixer l'orientation de l'instabilité initiale et de conduire à un treillis ordonné. On a étudié l'evolution de ce réseau de paraboles focales

Par P. Oswald; J. Béhar; M. Kléman

1982-01-01

11

Sedimentological and Logging Characteristics of the Dogger in the Geothermal Drilling Operation of Aulnay-Sous-Bois.  

National Technical Information Service (NTIS)

The present report gives the results of the ''core drilling/logging'' operation carried out on the reservoir of the DOGGER in the geothermal production well of Aulnay-sous-Bois. The aim of this study was to establish a methodology to get a better sediment...

D. Giot J. Rojas

1981-01-01

12

Approches expérimentale et théorique du comportement thermomécanique sous chargement multiaxial d'alliages à mémoire de forme polycristallins  

NASA Astrophysics Data System (ADS)

Depuis une dizaine d'années, des alliages à mémoire de forme (AMF) sont sollicités, en chargement multiaxial, dans le domaine de la pseudoélasticité (transformation martensitique “renversable” induite sous contrainte) et de la pseudoplasticité (réorientation des plaquettes de martensite sous l'effet des contraintes externes). Les résultats expérimentaux obtenus montrent que le choix du chemin de chargement multiaxial influe fortement sur la réponse mécanique de I'AMF. Actuellement, malgré les nombreux modèles proposés dans la littérature, la simulation des chargements nonproportionnels n'est pas tout à fait opératoire. C'est la raison pour laquelle un modèle de comportement des AMF sous chargements proportionnels et nonproportionnels est proposé dans ce papier. A cet effet, deux surfaces de transformation directe et inverse, une déformation et une contrainte équivalentes sont introduites dans le cadre de la thermodynamique des processus irréversibles. Pour un Cu-Al-Be polycristallin, la capacité de prédiction du comportement sous sollicitation complexe est bonne avec un nombre faible de paramètres matériau à identifier.

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

2002-12-01

13

Quality and safety of fish curry processed by sous vide cook chilled and hot filled technology process during refrigerated storage.  

PubMed

Fish curry, a traditional Indian dish was prepared from farmed fish Cobia (Rachycentron canadum), packaged by two different cook-chill processes namely, sous vide cook chilled and hot filled technology and held at 2?°C. Biochemical composition revealed that fish curry contained 5% protein and 6% fat. Omega-3 fatty acids, eicosapentaenoic acid (EPA) retained 55.44% while docosahexaenoic acid (DHA) retained 29% during cook-chilling process. The major fatty acids in fish curry were C18:2, C12:0, C16:0 and C18:1. Shelf-life of sous vide cook chilled and hot filled technology processed fish curry were 8 and 12 weeks, respectively. Total bacterial counts were detected after 4 weeks and 12 weeks in sous vide cook chilled and hot filled technology processes, respectively. Total staphylococci were detected in sous vide cook chilled and hot filled technology processed cobia fish curry after 4 and 12 weeks, respectively. Total bacilli, anaerobic sulfite reducing clostridia, Salmonella, and lactic acid bacteria were absent. Hot filled technology process was more efficient and could be applied for chilled fish curry preservation for 12 weeks without any safety problems. PMID:22701059

Shakila, R Jeya; Raj, B Edwin; Felix, N

2012-06-01

14

Integral modeling and financial impact of the geothermal situation and power plant at Soultz-sous-Forêts  

NASA Astrophysics Data System (ADS)

The science about deep Enhanced Geothermal Systems (EGS) is still an emerging process and for further spreading economics is the key of the technology. To understand the financial situation, a program for economic evaluation was developed. This software (Euronaut) is completely modularized and considers all cash flows. Projects like an EGS are wrapped into tree-like structures. Based on the results which were gained at Soultz-sous-Forêts, two configurations were designed. The first EGS configuration consists of a simplified two well (doublet) system where the dependencies of all components (mainly the reservoir, wells, pumps and the heat-to-power conversion unit) are physically and economically linked together. The realization of these dependencies and their complex interactions enable a sensitivity analysis of the borehole depth and reservoir depth, respectively. As a result, depth dependent effective costs and revenues of an EGS plant with the geohydrological characteristics of Soultz-sous-Forêts are determined. As a future development, the second configuration will adapt the actual situation at Soultz-sous-Forêts with the individual features of all four wells (GPK1 - GPK4). Then, this model can be used for all kinds of sensitivity analyses to clarify the impact of certain components or to optimize the operation scheme; e.g. the flow rates.

Heidinger, Philipp

2010-07-01

15

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 (74°C), cooled in ice water, and stored at 4.4°C for 0, 5, 10, 15, and 30 d. The lipid oxidation development of the meat was estimated by quantification of malonaldehyde (MDA) values, using the 2-thiobarbituric acid reactive substances analysis. Fatty acid, nonheme iron, moisture, and fat analyses were performed as well. Results showed that dietary CLA induced deposition of cis-9, trans-11 and trans-10, cis-12 CLA isomers, increased the proportion of saturated fatty acids, and decreased the proportions of monounsaturated and polyunsaturated fatty acids. Flaxseed oil induced higher deposition of C18:1, C18:2, C18:3, and C20:4 fatty acids, whereas MFO induced higher deposition of n-3 fatty acids, eicosapentaenoic acid (C20:5), and docosahexaenoic acid (C22:6; P < 0.05). Meat lipid oxidation stability was affected by the interaction of either dietary oil or vitamin E with storage day. Lower (P < 0.05) MDA values were found in the CLA treatment than in the MFO and FSO treatments. Lower (P < 0.05) MDA values were detected in meat samples from the 200 mg/kg of vitamin E than in meat samples from the 42 mg/kg of vitamin E. Nonheme iron values did not affect (P > 0.05) lipid oxidation development. In conclusion, dietary CLA, FSO, and MFO influenced the fatty acid composition of chicken muscle and the lipid oxidation stability of meat over the storage time. Supranutritional supplementation of vitamin E enhanced the lipid oxidation stability of sous vide chicken meat. PMID:21248346

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

2011-02-01

16

Étude expérimentale des transformations de phase dans un gradient thermique : application au granite de Soultz-sous-Forêts, FranceExperimental study of phase transformations in a thermal gradient: application to the Soultz-sous-Forêts granite (France)  

NASA Astrophysics Data System (ADS)

The circulation of an injected fluid in the deep granite of the Soultz-sous-Forêts HDR ('Hot Dry Rock') site causes important textural and mineralogical modifications. In order to determine the potential crystallization sequences along the fluid pathway, several experiments under thermal gradient were conducted at 600 bar (between 300 and 200 °C). After 40 days, the observed sequences of the newly formed products along the thermal gradient are always as follows, from high to low temperatures: quartz, feldspars, and finally interstratified clays, this implying a significant mobility of aluminium in the solution. To cite this article: A. Baldeyrou et al., C. R. Geoscience 335 (2003).

Baldeyrou, Armelle; Vidal, Olivier; Fritz, Bertrand

2003-04-01

17

Un indice d'endommagement local pour l'évaluation de murs en maçonnerie confinée sous chargement latéral cyclique  

Microsoft Academic Search

Résumé  Dans cet article, il est proposé un indice d'endommagement pour des murs en maçonnerie confinée par des éléments en béton\\u000a armé, sous chargement latéral cyclique. L'indice en question, basé sur la dégradation de la raideur latérale, est fonction\\u000a du niveau de déformation du mur.\\u000a \\u000a Une méthodologie simplifiée permet d'estimer le comportement des murs, avec l'utilisation de la méthode des éléments

M. Lafuente; M. Cruz; C. Genatios

1998-01-01

18

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

Heimlich, Christine; Masson, Frédéric; Gourmelen, Noël

2014-05-01

19

Synthèse dans les sels fondus de cristallites d'YBa2CU3O{7-x} et d'HoBa2CU3O{7-x} sous forme de plaquettes bien individualisées et orientation sous champ magnétique  

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 étudié la synthèse en sel fondu des phases supraconductrices YBa2CU3O{7-x} et HoBa2CU3O{7-x}. Les meilleurs résultats sont obtenus dans le mélange équimolaire des sels de chlorure de potassium et de sodium. Cette technique conduit à la formation de cristallites de dimensions microniques sous forme de plaquettes finement divisées. Nous avons ensuite entrepris l'élaboration de céramiques supraconductrices orientées de la phase HoBa2CU3O{7-x} par une méthode d'orientation induite par un champ magnétique. Nous présentons les premiers résultats de l'orientation sous champ magnétique d'une barbotine par la technique de coulée en moule poreux.

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

1991-11-01

20

Diagnostic X de la zone proche injecteur d'un jet cryogénique d'azote sous haute pression  

NASA Astrophysics Data System (ADS)

Une source impulsionnelle de rayons X, compacte produisant des photons d'énergie comprise entre 5 et 50keV, a été spécialement conçue au GREMI afin de pouvoir caractériser l'écoulement proche d'injecteurs cryogéniques (20premiers mm) sur l'installations M51 du DLR à Lampoldhausen à des pressions comprises entre 10 et 60bars et des températures allant de 100 à 130K. Pour la première fois, des radiographies d'un jet cryogénique d'azote pur sous haute pression en sortie d'injecteur ont été réalisées sans ajout de traceur. Les données obtenues (cônes d'expansion, densité) ont pu être comparées à celles mesurées par d'autres systèmes (ombroscopie, thermocouple) et présentent la radiographie comme particulièrement sensible et bien adaptée à ce genre de problématique.

Métay, B.; Robert, E.; Viladrosa, R.; Cachoncinlle, C.; Pouvesle, J. M.; Mayer, W.; Schneider, G.

2003-06-01

21

Effect of different temperature-time combinations on physicochemical, microbiological, textural and structural features of sous-vide cooked lamb loins.  

PubMed

Lamb loins were subjected to sous-vide cooking at different combinations of temperature (60, 70, and 80 °C) and time (6, 12, and 24 h). Different physicochemical, histological and structural parameters were studied. Increasing cooking temperatures led to higher weight losses and lower moisture contents, whereas the effect of cooking time on these variables was limited. Samples cooked at 60 °C showed the highest lightness and redness, while increasing cooking temperature and cooking time produced higher yellowness values. Most textural variables in a texture profile analysis showed a marked interaction between cooking temperature and time. Samples cooked for 24h showed significantly lower values for most of the studied textural parameters for all the temperatures considered. Connective tissue granulation at 60 °C and gelation at 70 °C were observed in the SEM micrographs. The sous-vide cooking of lamb loins dramatically reduced microbial population even with the less intense heat treatment studied (60 °C-6 h). PMID:23273466

Roldán, Mar; Antequera, Teresa; Martín, Alberto; Mayoral, Ana Isabel; Ruiz, Jorge

2013-03-01

22

The Influence Of Hydrothermal Alteration And Weathering On Rock Magnetic Properties Of Granites From The Eps1 Drilling (soultz-sous-forÊts \\/ France)  

Microsoft Academic Search

The EPS-1 drilling in Soultz-sous-Forêts (Rhinegraben, France) recovered a core pro- file of Tertiary to Permo-Mesozoic sediments deposited on a Variscan granitic base- ment. Magnetic susceptibility (k) measurements on the core material revealed a con- tinous increase from the basement\\/cover boundary (kmean 0.4 x 10-3 SI) into the magnetite-bearing granite (kmean 13 x 10-3 SI) over a depth range of

J. Just; A. Schleicher; A. Kontny; H. de Wall

2002-01-01

23

Tonsil Irradiation  

Cancer.gov

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

24

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

NASA Astrophysics Data System (ADS)

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

Gaucher, E.; Kohl, T.

2013-12-01

25

Gamma irradiators  

SciTech Connect

The commercial use of gamma radiation to sterilize medical equipment and supplies began in the late 1950s. This article describes the basic technology and design aspects of commercial irradiation facilities. It explains the safety features and interlocks which protect workers, the public, and the environment from radiation and radioactive material.

Cuda, J.; McKinnon, R.G. (Nordion International Inc. (US)); Baker, P.G. (Baxter/Convertors (US))

1989-02-01

26

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.

27

Irradiation Information  

NSDL National Science Digital Library

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

1997-01-01

28

Detection of fractures within the Soultz-sous-Forêts EGS geothermal reservoir by processing of Vertical Seismic Profile data  

NASA Astrophysics Data System (ADS)

The 4 component multi-source/multi-offset VSP (Vertical Seismic Profile) conducted at the Soultz-sous-Forêts EGS (Enhanced Geothermal System) site in 2007 provides records of seismic waves recorded in the fractured granite basement within wells GPK3 and GPK4. Waves generated at 26 surface positions, located at distances between 500m and 5km from the well head in different azimuths, are recorded by 3 component geophones at depths between 5000m and 3000m with a 20m depth interval. The seismic source is a vibrator emitting a 16s long sweep with frequencies varying linearly between 8 and 88 Hz. Two shot locations were simultaneously recorded, one with an upsweep [8 to 88Hz], the other with a downsweep [88 to 8Hz]. Successive correlation with the two sweeps allows retrieving distinct seismograms for each shot from the mixed raw uncorrelated records. Most records show clear downgoing P and S waves. Detecting waves reflected or diffracted by fractures intersecting the wells requires extracting low amplitude upgoing waves from the dominant downgoing wavefield. However, the up to 30° inclination of the well relative to the vertical and the 60 to 90° dips of the fracture zones make the separation of the different waves complex. The wavefield separation of the vertical geophone component is done in the frequency-wavenumber Fourier domain which separates waves according to their apparent velocity across the receiver antenna. Picking of the first arrival times and shifting times allows aligning predominant P wave downgoing wavefield at constant times, or infinite apparent velocity in Fourier domain. Filtering the infinite apparent velocity attenuates all the waves having the same apparent velocity as the first arrivals. A second filtering at the downgoing S waves velocities is then applied, providing two downgoing wavefields, one for the P waves and the other for the S waves. The residuals correspond to the upgoing wavefield. To reduce the reverberations in the upgoing wavefield, we apply a Wiener deconvolution. Faint coherent waves that may originate from fractures are observed in restricted depth intervals. In order to model the arrival times of the extracted reflections/diffractions at the different shot positions, we need a velocity model of the 1400m thick sedimentary cover. P velocities from VSP data of one shot recorded in well GPK4 in sediments and structural information from geological logs and interpreted surface seismic profiles are used to build an initial 3D model with 3 layers separated by dipping plane interfaces. 3D ray tracing is used to compute first arrival times and adjust our model to the data, by modifying the dip of the interfaces. It is then possible to adjust the upgoing waves arrival times to reflections or diffractions on fractures in the reservoir.

Lubrano Lavadera, P.; Marthelot, J. M.; Zillmer, M.; Cornet, F.

2012-04-01

29

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

NASA Astrophysics Data System (ADS)

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

Delobelle, P.; Robinet, P.

1994-08-01

30

Effet laser à température ambiante sous pompage optique continu d'un VCSEL en cavité externe émettant à 1,55 ?m  

NASA Astrophysics Data System (ADS)

Nous présentons l'obtention du fonctionnement laser en continu à température ambiante à 1,55 ?m d'un laser semiconducteur à émission par la surface en cavité verticale et externe sous pompage optique. La structure est réalisée en une seule étape d'épitaxie par EPVOM sur un substrat d'InP. Les seuils observés sont inférieurs à 8,5 kW/cm2 à 20circC, et la puissance émise atteint 4 mW à 0circC. Une modélisation du comportement thermique de la structure nous a permis d'estimer sa résistance thermique à environ 470 K/W, et de simuler la variation de puissance émise pour différentes températures de fonctionnement.

Symonds, C.; Sagnes, I.; Oudar, J.-L.; Bouchoule, S.; Strassner, M.

2004-11-01

31

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 était d’étudier la cinétique de la Troponine Ic (TnIc) après chirurgie cardiaque sous circulation extracorporelle (CEC) et établir des valeurs seuils de TnIc pour le diagnostic d'infarctus du myocarde (IDM) post opératoire. Il s'agissait d'une étude prospective type cohorte observationnelle. Méthodes Nous avons inclus 37 patients âgés de plus de 18 ans proposés pour chirurgie valvulaire ou pontage aorto coronarien sous CEC. Nous avons suivi la cinétique de TnIc par des dosages immunoenzymatique sur mini-vidas® avant et après la CEC, à H4 et H12 postopératoire puis tous les jours les 4 premiers jours. Le cutoff pour le diagnostic d'IDM post opératoire a été défini comme la valeur moyenne de troponine + deux déviations standards des patients indemnes de complications cardiaques. Résultats Les valeurs de TnIc en préopératoire étaient toutes inférieures au seuil de détection de la méthode de dosage (<0,01µg/l). Les valeurs de TnIc augmentent en postopératoire immédiat pour atteindre un maximum à H4 puis diminuent progressivement pour se normaliser après 4 à 5 jours. Les valeurs seuils ont été déterminées pour H0, H4,H12, H24, H48, H72, H96 et ont été 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 cinétique de TnIc lors de chirurgie cardiaque non compliquée et la fixation de valeur seuil ou Cutoff permet aux cliniciens de distinguer entre dommage myocardique secondaire à la chirurgie et IDM.

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

2012-01-01

32

Safety Evaluation of Sous Vide-Processed Products with Respect to Nonproteolytic Clostridium botulinum by Use of Challenge Studies and Predictive Microbiological Models  

PubMed Central

Sixteen different types of sous vide-processed products were evaluated for safety with respect to nonproteolytic group II Clostridium botulinum by using challenge tests with low (2.0-log-CFU/kg) and high (5.3-log-CFU/kg) inocula and two currently available predictive microbiological models, Food MicroModel (FMM) and Pathogen Modeling Program (PMP). After thermal processing, the products were stored at 4 and 8°C and examined for the presence of botulinal spores and neurotoxin on the sell-by date and 7 days after the sell-by date. Most of the thermal processes were found to be inadequate for eliminating spores, even in low-inoculum samples. Only 2 of the 16 products were found to be negative for botulinal spores and neurotoxin at both sampling times. Two products at the high inoculum level showed toxigenesis during storage at 8°C, one of them at the sell-by date. The predictions generated by both the FMM thermal death model and the FMM and PMP growth models were found to be inconsistent with the observed results in a majority of the challenges. The inaccurate predictions were caused by the limited number and range of the controlling factors in the models. Based on this study, it was concluded that the safety of sous vide products needs to be carefully evaluated product by product. Time-temperature combinations used in thermal treatments should be reevaluated to increase the efficiency of processing, and the use of additional antibotulinal hurdles, such as biopreservatives, should be assessed.

Hyytia-Trees, Eija; Skytta, Eija; Mokkila, Mirja; Kinnunen, Arvo; Lindstrom, Miia; Lahteenmaki, Liisa; Ahvenainen, Raija; Korkeala, Hannu

2000-01-01

33

Gamma -ray irradiation head for panoramic irradiation  

SciTech Connect

The invention relates to a gamma -ray irradiation head for panoramic irradiation comprising a tungsten target revolving about an axis, and means for deflecting electrons around the same axis for producing photons in several directions either successively or simultaneously. When the beam of electrons is deflected in its entirety and when the impact zone moves on the target about the axis, the axis of the radiation lobe moves in the same way and permits irradiation according to a variable azimuth.

Azam, G.; Bensussan, A.

1980-10-21

34

Soybean, palm kernel, and animal-vegetable oils and vitamin E supplementation effect on lipid oxidation stability of sous vide chicken meat.  

PubMed

There is an increasing demand in precooked chicken meat products for restaurants and catering services. Because cooked chicken meat develops lipid oxidation relatively fast, sous vide chicken meat was studied to assess its shelf-life. Six hundred Cobb x Ross broilers were fed for 6 wk with a basal corn-soybean meal diet including soybean, palm kernel, or animal-vegetable oil, each supplemented with 33 or 200 mg/kg of dl-alpha-tocopheryl acetate. Broilers were randomly assigned into 6 treatments and 4 repetitions with 25 birds each. Boneless breast or thigh muscle pieces were dissected into 5 x 5 x 5 cm cubes, vacuum-packed, cooked in water bath (until 74 degrees C internal temperature), chilled, and stored at 4 degrees C for 1, 5, 10, 25, and 40 d. For each storage day, each pouch contained 3 pieces of meat, either breast or thigh. Thiobarbituric acid reactive substances analysis, to quantify malonaldehyde (MDA) values, was conducted to estimate the lipid oxidation development. Nonheme iron values of cooked meat were analyzed. Fatty acid methyl esters analysis was performed in chicken muscle to determine its fatty acid composition. There was no interaction between dietary fat and vitamin E level in all of the variables studied except in nonheme iron. Dietary fat significantly influenced the fatty acid composition of the muscle (P < 0.01), but it did not affect the MDA values, regardless of differences in the muscle fatty acid composition between treatments. Supplementation of the high level of vitamin E significantly reduced the MDA values in both breast and thigh meat (P < 0.01). The maximum MDA values were observed at d 40 of storage in thigh and breast meat in animal-vegetable and soybean oil treatments with the low levels of vitamin E, 0.91 and 0.70 mg/kg, respectively. Nonheme iron values in thigh meat differed between treatments at 1 or 25 d of storage but not in breast meat. In conclusion, refrigerated sous vide chicken meat has a prolonged shelf-life, which is enhanced by dietary supranutritional supplementation of vitamin E. PMID:20308404

Narciso-Gaytán, C; Shin, D; Sams, A R; Bailey, C A; Miller, R K; Smith, S B; Leyva-Ovalle, O R; Sánchez-Plata, M X

2010-04-01

35

Facts about food irradiation: Food irradiation costs.  

National Technical Information Service (NTIS)

This fact sheet gives the cost of a typical food irradiation facility (US $1 million to US $3 million) and of the food irradiation process (US $10-15 per tonne for low-dose applications; US $100-250 per tonne for high-dose applications). These treatments ...

1991-01-01

36

Solar Irradiation over Zambia.  

National Technical Information Service (NTIS)

Angstroem-Page linear regression equation between global irradiation and sunshine duration is fitted for five Zambian locations for which the direct measured values of the global irradiation exist. Excellent correlation is found to exist for all the five ...

P. C. Jain

1983-01-01

37

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

38

Main characteristics of the deep geothermal brine (5 km) at Soultz-sous-Forêts (France) determined using geochemical and tracer test data  

NASA Astrophysics Data System (ADS)

Three deep wells (5000 m) have been drilled into a fractured granite basement at Soultz-sous-Forêts, within the Tertiary Rhine Graben, in order to develop a heat exchanger and produce electricity after the creation of an EGS reservoir. Very few analyses representative of the deep geothermal fluids are available because of frequent contamination by drilling fluids or injected waters. These indicate similar chemical and isotopic compositions (NaCl fluids) and high salinities (about 100 g/l) suggesting a common sedimentary origin and identical water-rock interaction processes at equilibrium temperatures close to 230 °C in a sedimentary rather than a granite reservoir. The latter would be situated closer to the Graben centre where the Triassic Buntsandstein formation is deepest and hottest. Tracer tests conducted after 2000 show that the deep native geothermal brine is omnipresent in the fluids discharged during the production and circulation tests. Its natural convective flux was estimated at 1-1.2 m 3/h.

Sanjuan, Bernard; Millot, Romain; Dezayes, Chrystel; Brach, Michel

2010-07-01

39

Physico-chemical, textural and structural characteristics of sous-vide cooked pork cheeks as affected by vacuum, cooking temperature, and cooking time.  

PubMed

This paper describes the influence of different factors on sous-vide cooked pork. Pork cheeks were cooked at different combinations of temperature (60°C or 80°C), time (5 or 12h) and vacuum (vacuum or air packaged). Weight losses were lower and moisture content higher in samples cooked for a shorter time (P=0.054) and at a lower temperature (P<0.001). Samples cooked at 60°C showed more lightness (L*) and redness (a*) (P<0.001). Lipid oxidation showed an interaction between cooking time and temperature (P=0.007), with higher TBARs values for samples cooked for 12h at 60°C and lower for those cooked for 12h at 80°C. Samples cooked at 80°C for 12h showed lower (P<0.05) values for most textural parameters than all the other types of samples. Vacuum packaging showed no influence on any of the studied variables. For the treatments evaluated, cooking temperature×time combination seems to be more important than vacuum packaging in the textural and colour parameters of pork cheeks. PMID:22154568

Sánchez Del Pulgar, José; Gázquez, Antonio; Ruiz-Carrascal, Jorge

2012-03-01

40

The Influence Of Hydrothermal Alteration And Weathering On Rock Magnetic Properties Of Granites From The Eps-1 Drilling (soultz-sous-forÊts / France)  

NASA Astrophysics Data System (ADS)

The EPS-1 drilling in Soultz-sous-Forêts (Rhinegraben, France) recovered a core pro- file of Tertiary to Permo-Mesozoic sediments deposited on a Variscan granitic base- ment. Magnetic susceptibility (k) measurements on the core material revealed a con- tinous increase from the basement/cover boundary (kmean 0.4 x 10-3 SI) into the magnetite-bearing granite (kmean 13 x 10-3 SI) over a depth range of 1417 U 1555 m. Rock magnetic and mineralogic studies were performed for the fresh granite, the hydrothermally altered granite near a fault zone and the altered granite from the fossil land surface near the basement/cover boundary. The decrease in susceptibility can be correlated with a gradual decomposition of magnetite to hematite and an alteration of the matrix minerals feldspars, biotite and hornblende to clay minerals and carbon- ates. Along with this transition, characteristic rock magnetic signatures can be dis- criminated for different degrees of alteration. While temperature-dependent magnetic susceptibility k(T)-curves in fresh granites indicate a typical multidomain magnetite course with good reversibility, different types of irreversible courses are observed for the altered granite. However, hematite could not be identified in the k(T)-curves. Al- tered granite shows relatively weak magnetic behaviour in AF-demagnetisation exper- iments, untypical for hematite. The alteration of the fresh granite also causes a change in magnetic fabric parameter, especially of the anisotropy factor. The magnetic min- eralogy from the altered granite in respect to the changes in rock magnetic properties will be discussed.

Just, J.; Schleicher, A.; Kontny, A.; de Wall, H.

41

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

NASA Astrophysics Data System (ADS)

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

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

2002-07-01

42

Facts about food irradiation: Irradiated foods and the consumer.  

National Technical Information Service (NTIS)

This fact sheet discusses market testing of irradiate food, consumer response to irradiated products has always been positive, and in some countries commercial quantities of some irradiated food items have been sold on a regular basis. Consumers have show...

1991-01-01

43

Alaskan Commodities Irradiation Project  

SciTech Connect

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

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

1988-12-01

44

Combustible caramel pour reacteurs de recherche: Experience acquise en fabrication, controles et irradiation du coeur d'osiris  

NASA Astrophysics Data System (ADS)

L'un des aboutissements des différentes actions menées en France concernant la conception, la fabrication et le développement des combustibles nucléaires a été la mise au point par le CEA d'un combustible de type plaque (combustible CARAMEL) susceptible d'être adapté a différentes catégories de réacteurs à eau (réacteur de puissance, propulsion navale, chauffage urbain, pile de recherche). Ces travaux ont été couronnés par la réalisation de tout un coeur et des recharges du réacteur de recherche à hautes performances, Osiris, à Saclay. L'ancien combustible en alliage U Al fortement enrichi a eté remplacé par un combustible caramel de faible enrichissement (7%), non proliférant. Ce nouveau coeur fonctionne avec satisfaction, depuis janvier 1980. Après une brève description des caractéristiques du combustible caramel et de ses principaux avantages, on présente sa fabrication ainsi que l'ensemble des contrôles de qualité auxquels il est soumis. Le programme de qualification ainsi que les principaux résultáts qui en ont été tirés sont exposés. On décrit également le programme de suivi du combustible en pile dont le but est de s'assurer du bon comportement du combustible sous irradiation. Le bon fonctionnement d'Osiris, qui a terminé 11 cycles d'irradiation le 21 avril 1981, a permis de montrer le bien fondé des choix effectués et l'excellent comportement de l'élément combustible dans les conditions pourtant sévères d'un réacteur de recherche à hautes performances.

de Contenson, Ghislain; Foulquier, Henri; Trotabas, Maria; Vignesoult, Nicole; Cerles, Jean-Marie; Delafosse, Jacques

1982-04-01

45

Interfaces under Laser Irradiation.  

National Technical Information Service (NTIS)

This lecture deals with structural and chemical changes in binary samples induced by short laser pulses, typically pulses in the ns regime. The reaction of a composite sample to irradiation by a short laser pulse is, conceptually and experimentally, much ...

M. F. von Allmen

1982-01-01

46

Stability of ?-Irradiated Carmine  

NASA Astrophysics Data System (ADS)

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

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

2005-01-01

47

Interdiffusion de puits quantiques controlee par irradiation laser excimere pour l'integration de composants photoniques  

NASA Astrophysics Data System (ADS)

L'integration de composants discrets sur un systeme unique, tel une puce electronique, augmente les performances totales du systeme, fait apparaitre de nouvelles fonctionnalites et diminue les couts associes a la fabrication des dispositifs. Ces ameliorations, appliquees au secteur de la microelectronique, sont grandement responsables des avancements importants qu'ont connus les technologies de l'information et des communications au cours des dernieres annees. Puisque la fabrication de circuits photoniques integres necessite l'integration de structures ayant des bandes interdites differentes a partir d'une meme puce semiconductrice, leur niveau d'integration est bien inferieur que celui atteint pour un microprocesseur standard. Parmi les techniques ayant le potentiel de fabriquer des circuits photoniques integres monolithiquement, l'interdiffusion de puits quantique post-expitaxial controlee spatialement augmente la bande interdite d'une heterostructure semiconductrice a l'interieur de regions definies. Le processus d'interdiffusion, active thermiquement, est accelere par la diffusion d'impuretes et de defauts ponctuels tels que les lacunes et les interstitiels. L'hypothese de depart de mes travaux de doctorat suppose que la radiation laser ultra-violette module la diffusion et la generation de defauts ponctuels dans les heterostructures reposant sur les technologies a base de GaAs et d'InP et, consequemment, controle spatialement l'interdiffusion de puits quantiques. Nous avons demontre que lorsque appliquee sur des heterostructures a base de GaAs, l'irradiation laser excimere l'interdiffusion en favorisant la croissance d'un stresseur de surface qui empeche la diffusion des defauts ponctuels vers les puits quantiques. Nous avons souligne l'influence de la vapeur d'eau physisorbee sur la croissance du stresseur et avons determine la resolution spatiale de la technique. Dans les heterostructures basees sur les technologies InP, meme sous le seuil d'ablation, l'absorption des impulsions laser UV favorise la desorption des atomes de surface ce qui genere des defauts ponctuels en concentration excedentaire. Lors d'un recuit thermique, ces defauts ponctuels augmentent la vitesse de l'interdiffusion sous les regions irradiees. Mots cles : Interdiffusion de puits quantique, integration potonique, laser excimere, semiconducteur, InP, GaAs.

Genest, Jonathan

48

ORNL irradiation creep facility  

SciTech Connect

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

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

1980-09-01

49

Étude expérimentale du comportement cyclique d'un acier du type 316 L sous chargement multiaxial complexe en traction-torsion-pressions interne et externe  

NASA Astrophysics Data System (ADS)

This paper is concerned with the experimental determination of the behaviour of a 316 L austenitic stainless steel at room temperature and under non proportional cyclic strainings in tension-torsion- internal and external pressures. The two or three sinusoïdal strains were applied both in and out-of-phase and the main investigations deal with the additional hardening due to multiaxiality of the loadings. Typical stabilized hysteresis loops are presented. With respect to the maximum additional hardening the different tests can be classified as follows : in phase tests, out-of-phase internal-external pressures tests, out-of-phase tension-torsion tests and finally tension-torsion-pressure with significant phase angles A device is presented which allows cyclic tests to be performed on tubes for loadings in tension-torsion-internal and external pressures. It is composed of a medium pressure chamber enclosing the gage length of the test specimen, directly fixed on the specimen and connected to two pressure regulators. The specimen is also fastened to the jaws of a hydraulic tensile-torsion machine through two extension rods. The entire device is controlled with the help of strain gauges set directly on the gage zone of the test specimen. Different tests have been performed at ambient temperature on an austenitic stainless steel which has the particularity of presenting a strong supplementary hardening connected to the non-radiality of the loadings. The influence of the phase shift parameters, namely the angles ? and \\varphi (?: tension-torsion, \\varphi: tension-pressures) for two or three cyclic sinusoïdal components and for a total equivalent strain amplitude level imposed at 0.4% was studied. The ratios of the maximum strain amplitudes were respectively fixed at r_2 = 1 and r_1 = ± 1 (r_2: tension-torsion and r_1: tension-pressures). These tests allowed both the hypotheses made in stress calculations and the whole of the experimental set up to be validated. They are very rich in informations and lead to classify the different types of loading, with two or three cyclic components, with respect to the observed supplementary hardening. This classification was established as follows: i) The in-phase tests with two or three components (? = \\varphi = 0^circ); no supplementary hardening is observed. ii) The tension-pressure tests such as r_1 = 1, \\varphi = 90^circ and r_1 = - 1, \\varphi = 60^circ, the hardening is slightly inferior to that of tension-torsion tests. iii) The tension-torsion tests such as r_2 = 1 and ? = 90^circ, where a substantial additionnal hardening takes place. iv) The tension-torsion-pressure tests where the three components are strongly shifted, namely: r_1 = r_2 = 1, ? = 90^circ and \\varphi = 60^circ, and r_2 = 1, r_1 = -1, ? = 41.4^circ and \\varphi = 82.8^circ. The hardening is slightly superior to the one recorded in tension-torsion. A more thorough study is in preparation which considers all the possible combinations in tension-torsion-pressures, and will be performed on the same material. The early results tend to validate the observations presented in this article. Cette étude réside dans la détermination expérimentale du comportement à la température ambiante de l'acier inoxydable 316 L sous chargement cyclique non proportionnel en traction-torsion-pressions interne et externe. Les deux ou trois déformations sinusoïdales appliquées sont soit en phase, soit hors-phase et l'on étudie l'amplitude du durcissement supplémentaire en fonction du degré de multiaxialité. On présente quelques boucles stabilisées typiques. Par rapport au durcissement supplémentaire maximal, les différents essais peuvent être classés comme suit: essais en phase (pas de durcissement supplémentaire), essais de traction-pressions hors-phase, essais de traction-torsion hors phase et essais de traction-torsion-pressions avec déphasages conséquents.

Bocher, L.; Delobelle, P.

1997-09-01

50

Facts about food irradiation: Nutritional quality of irradiated foods.  

National Technical Information Service (NTIS)

This fact sheet briefly considers the nutritional value of irradiated foods. Micronutrients, especially vitamins, are sensitive to any food processing method, but irradiation does not cause any special nutritional problems in food. 4 refs. (Atomindex cita...

1991-01-01

51

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

52

Update on meat irradiation  

SciTech Connect

The irradiation of meat and poultry in the United States is intended to eliminate pathogenic bacteria from raw product, preferably after packaging to prevent recontamination. Irradiation will also increase the shelf life of raw meat and poultry products approximately two to three times the normal shelf life. Current clearances in the United States are for poultry (fresh or frozen) at doses from 1.5 to 3.0 kGy and for fresh pork at doses from 0.3 to 1.0 kGy. A petition for the clearance of all red meat was submitted to the Food and Drug Administration (FDA) in July 1994. The petition is for clearances of fresh meat at doses from 1.5 to 4.5 kGy and for frozen meat at {approximately}2.5 to 7.5 kGy. Clearance for red meat is expected before the end of 1997. There are 28 countries that have food irradiation clearances, of which 18 countries have clearances for meat or poultry. However, there are no uniform categories or approved doses for meat and poultry among the countries that could hamper international trade of irradiated meat and poultry.

Olson, D.G. [Iowa State Univ., Ames, IA (United States)

1997-12-01

53

Energy and Food Irradiation.  

National Technical Information Service (NTIS)

This paper shows that significant energy savings can be obtained by use of irradiation preservation. The energy used in food systems in the US amounts to about 16.5% of the total energy. An analysis of the energy used in the many steps of the food irradia...

A. Brynjolfsson

1978-01-01

54

Combination processes in food irradiation  

Microsoft Academic Search

Irradiation is emerging as a potential method of food preservation. It is being used to extend the shelf life of raw and processed foods in many countries worldwide. Like all other methods of food preservation, irradiation has a number of limitations. Irradiation, when used alone, can cause the development of undesirable sensory and chemical changes in some foods, depending on

B. R. Thakur; R. K. Singh

1995-01-01

55

INDUCED CONDUCTIVITIES IN IRRADIATED POLYETHYLENE  

Microsoft Academic Search

Induced conductivities in irradiated polyethylene were observed as ; functions of dose rate and applied voltage. Irradiated polyethylenes were ; prepared with electron beams from a Van de Graaff Generator. The total doses of ; radiation were from about 10⁷ rad to 10⁸ rad. The experiments on ; induced conductivities were carried out under gamma irradiation from Co⁶°. ; The

K. Yahagi; K. Shinohara; K. Mori; E. Fukada

1963-01-01

56

Irradiation direction from texture.  

PubMed

We present a theory of image texture resulting from the shading of corrugated (three-dimensional textured) surfaces, Lambertian on the micro scale, in the domain of geometrical optics. The derivation applies to isotropic Gaussian random surfaces, under collimated illumination, in normal view. The theory predicts the structure tensors from either the gradient or the Hessian of the image intensity and allows inferences of the direction of irradiation of the surface. Although the assumptions appear prima facie rather restrictive, even for surfaces that are not at all Gaussian, with the bidirectional reflectance distribution function far from Lambertian and vignetting and multiple scattering present, we empirically recover the direction of irradiation with an accuracy of a few degrees. PMID:14570101

Koenderink, Jan J; Pont, Sylvia C

2003-10-01

57

HSC senescence upon irradiation.  

PubMed

In this issue of Blood, Shao et al report that a side effect of total body irradiation (TBI) is long-term bone marrow injury and thus dysfunctional hematopoiesis caused by the induction of hematopoietic stem cell (HSC) senescence. Interestingly and unexpectedly, however, this happens in a manner independent of the cell-cycle regulators Ink4a and Arf, which play a major role in senescence in other cell systems. PMID:24832936

Geiger, Hartmut

2014-05-15

58

Irradiation of blood products  

SciTech Connect

The method of treating white blood cells is described comprising irradiating a thin film of blood product containing white blood cells with ultraviolet radiation predominantly of a wavelength of 280 to 320 nanometers at an intensity of 4 to 15 milliwatts per square cm., to provide a total energy exposure of 800 to 2800 millijoules per square cm. of ultraviolet radiation for a sufficient time. The white blood cells substantially lose their capability to set off an immune reaction in an alloimmunized patient.

Miripol, J.E.; Bilstad, A.; Foley, J.; Glash, D.

1988-02-23

59

Hyperparathyroidism after neck irradiation.  

PubMed

A retrospective review of 1550 cases of hyperparathyroidism (HPT) treated surgically over a 30-year period reveals a past history of exposure to neck irradiation in 10 cases (0.7 per cent). The indication for radiotherapy was benign disease in nine and papillary thyroid carcinoma in one case. The mean interval between radiation exposure and the detection of HPT was 32 years (range 3-63 years). Patients treated with radioactive iodine alone developed HPT after a mean of 5 years while the interval for those treated with external beam therapy alone was a mean of 44 years. The parathyroid histology was adenoma in six cases, carcinoma in three cases and nodular hyperplasia in one case. All patients had coincident benign thyroid disease apart from one that had previously had papillary carcinoma and another with follicular carcinoma. Neck irradiation has been shown to confer an increased risk of HPT due to parathyroid adenoma and carcinoma. Radiotherapy for benign disease has generally been abandoned and these cases demonstrate a further contra-indication for the use of neck irradiation. PMID:3179662

Christmas, T J; Chapple, C R; Noble, J G; Milroy, E J; Cowie, A G

1988-09-01

60

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

61

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

62

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

NASA Astrophysics Data System (ADS)

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

Lezaud, J.-M.; Chaissé, F.

1993-02-01

63

Post-irradiation pituitary sarcoma  

Microsoft Academic Search

A fibrosarcoma developed in the pituitary fossa of a patient who had been irradiated 13 years previously for treatment of pituitary adenoma. The tumor was a large aggressively growing spindle cell neoplasm which eroded adjacent structures, causing increased intracranial pressure, and eventual cerebellar tonsillar herniation. In common with previously described post-irradiation sarcomas of the pituitary, this lesion developed in the

H. C. Powell; L. F. Marshall; R. J. Ignelzi

1977-01-01

64

Consumer attitude toward food irradiation  

SciTech Connect

Consumer attitudes toward food irradiation were evaluated. The influence of educational efforts on consumer concern for the safety of irradiated products and willingness to buy irradiated foods were measured. Demographic and psychological factors were studied in relation to attitudes. An educational leaflet describing current scientific information regarding the safety, advantages, and disadvantages of food irradiation was developed and used in two studies evaluating attitude change. In the first study, attitude change among two groups of consumers with different philosophic orientations was measured. In a second study, the effectiveness of an educational leaflet received through the mail and a poster display were examined. In a third study response to food irradiation was related to value hierarchy, locus of control, innovativeness, and demographic parameters. Initially, subjects showed a higher concern for other areas of food safety, particularly the use of chemicals and sprays on food, than toward food irradiation. After educational efforts, conventional consumers expressed minor concern toward irradiation whereas ecologically sensitive alternative consumers obtained from a food cooperative expressed major concern. A knowledgeable discussion leader lowered irradiation concern among conventional consumers. In contrast, concern among alternative consumers did not diminish when given the opportunity to discuss safety issues with a knowledgeable person.

Bruhn, C.M.M.

1986-01-01

65

Operation of the Irradiation Facilities.  

National Technical Information Service (NTIS)

In 1984, 72 companies utilized the 100kCi Co-60 irradiation facility for sterilization of medical products such as surgical gloves, cotton tips etc., or for preservation of food products. A total of 45,491 cartons of 46 different items were irradiated wit...

Y. S. Yoo H. W. Chung J. H. Jin S. C. Park

1985-01-01

66

Solar irradiance spectrum at Madrid  

NASA Astrophysics Data System (ADS)

An experimental study of the spectrum of direct solar irradiance in Madrid on dear days has been made. The expression I(?) = (1/S)I 0(?)exp(-?)sec? s){(cos? s)[1 + sec? s(0.13 ?/? 1.5)]} is proposed to describe more realistically the real direct solar spectral irradiance in Madrid.

Pons, A.; Corróns, A.

67

Development of data base on food irradiation.  

National Technical Information Service (NTIS)

For the exact understanding on food irradiation in Japan, it is important to provide information of food irradiation to consumers, industries and government offices. However, many of information on food irradiation are only restricted in a few experts or ...

H. Ito T. Kume S. Hashimoto F. Izumi

1995-01-01

68

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.

69

Modifications de l'expression des gènes GST-? et p53 dans des lignées tumorales cellulaires humaines O.R.L. après irradiation gamma : induction, études cellulaires et moléculaires  

NASA Astrophysics Data System (ADS)

Cell sub-populations surviving to high radiation doses were selected. The KBm survival part was obtained by exposure to a mutagenic agent and irradiation, FaDum results of a progressive irradiation of FaDu. A semi-quantitative RT-PCR analysis revealed a significant overexpression of GST-? and p53 genes for KBm and FaDum cell lines that remained stable for 18 months. The SF2, ?, ?, and MID parameters, determined by clonogenic assays, show no modifications of radiosensitivity. The variations of expression observed are not correlated to a radiosensitivity variation. The overexpression of GST-? and p53 does not seem to be a radiosensitivity marker. Nous avons isolé des sous-populations de 2 lignées cellulaires humaines (KB et FaDu) de carcinomes des voies aéro-digestives supérieures survivant à de fortes doses d'irradiation. La fraction survivante KBm a été obtenu après exposition à un agent mutagène et à une irradiation, FaDum résulte de l'irradiation progressive de FaDu. Une analyse par RT-PCR semi-quantitative nous a permis de mettre en évidence une surexpression significative des gènes GST-? et p53 pour les souches KBm et FaDum analysées après 18 mois de culture. Les paramètres, ?, ?, SF2, MID, déterminés par essais clonogéniques, n'indiquent pas de modification de la radiosensibilité. Les variations d'expression observées ne sont donc pas corrélées à une variation de radiosensibilité. La surexpression des gènes GST-? et p53 ne semble pas constituer un marqueur de radiosensibilité.

Dubessy, C.; Merlin, J. L.; Marchal, C.

1998-04-01

70

AFIP-4 Irradiation Summary Report  

SciTech Connect

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

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

2011-09-01

71

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

72

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.

73

Irradiation of Northwest agricultural products  

SciTech Connect

Irradiation of food for disinfestation and preservation is increasing in importance because of increasing restrictions on various chemical treatments. Irradiation treatment is of particular interest in the Northwest because of a growing supply of agricultural products and the need to develop new export markets. Several products have, or could potentially have, significant export markets if stringent insect control procedures are developed and followed. Due to the recognized potential benefits of irradiation, Pacific Northwest Laboratory (PNL) is conducting this program to evaluate the benefits of using irradiation on Northwest agricultural products under the US Department of Energy (DOE) Defense Byproducts Production and Utilization Program. Commodities currently included in the program are cherries, apples, asparagus, spices, hay, and hides.

Eakin, D.E.; Tingey, G.L.

1985-02-01

74

Coal Investigations Using Laser Irradiation.  

National Technical Information Service (NTIS)

Conditions necessary to obtain optimum yield of useful products when coal is rapidly heated to extreme temperatures by laser irradiation were determined. Product distribution and yield were investigated as functions of several variables. Low-rank coals wi...

F. S. Karn A.G. Sharkey A.F. Logar R. A. Friedel

1970-01-01

75

Food Preservation (Except by Irradiation).  

National Technical Information Service (NTIS)

The bibliography lists 213 reports and translations on food preservation (except by irradiation) added to the CFSTI collection from June 1962 through February 1965. It includes research on additives, sterilization, pasteurization, biochemical treatment, s...

1965-01-01

76

Nutritional Quality of Irradiated Foods.  

National Technical Information Service (NTIS)

The review presents representative data on the nutritional quality of irradiated foods and brings into focus some of the possible problem areas. Radappertization at low temperatures greatly improves the nutritional quality in regard to the micronutrients ...

J. Scott N. Raica W. Nielsen

1972-01-01

77

Infrared Spectroscopic Study of ?-Irradiated Cotton Linters  

Microsoft Academic Search

Cotton linters is irradiated by Co-60 source with different doses (5 … 52 Mrad). The effect of ?-irradiation on the grafting of cotton linters with methylmethacrylate monomer (MMA) is clarified, crystallinity index (CrI) of irradiated samples decreases by increasing the radiation dose. A new hand appeared at 1715 cm (C=O) after irradiation. On the other hand, band intensities of some

A. A. Shabaka; A. M. El-Agramy; A. M. A. Nada

1991-01-01

78

Gamma-irradiated dry fruits  

Microsoft Academic Search

EPR spectra of dry, sugar containing fruits—raisins, sultanas, figs, dates, peaches, blue plums and chokeberry recorded before and after irradiation with gamma-rays, are reported. It is shown that weak singlet EPR line with 2.0031±0.0005 can be recorded before irradiation of seeds, stones or skin of chokeberry, figs and raisins as well as flesh of blue plum, raisins and peaches. EPR

Nicola D. Yordanov; Zdravka Pachova

2006-01-01

79

Irradiation induced creep of graphite  

NASA Astrophysics Data System (ADS)

The status of graphite irradiation induced creep strain prediction is reviewed and major creep models are described. The ability of the models to quantitatively predict the irradiation induced creep strain of graphite is reported. Potential mechanisms of in-crystal creep are reviewed as are mechanisms of pore generation under stress. The case for further experimental work is made and the need for improved creep models across multi-scales is highlighted.

Burchell, T. D.; Murty, K. L.; Eapen, J.

2010-09-01

80

Restenosis after pulsed laser irradiation  

NASA Astrophysics Data System (ADS)

This study was designed to assess the depth and extent of chronic lesions induced by clinically relevant doses of excimer or Ho:YAG laser irradiation in an animal model of normal arterial wall. Normal iliac arteries of 14 male New Zealand rabbits were irradiated with excimer laser and 7 contralateral sites were irradiated with Ho:YAG laser. The lasers were coupled to a 1.4 and 1.5 mm multifiber wire guided catheter for excimer and Ho:YAG laser, respectively. The catheter was introduced through the carotid artery and positioned coaxially over the guide wire into the common iliac artery. After 28 days the irradiated sites were excised for light microscopy. Arterial wall lesions were assessed at the site of irradiation and at 30 mm antegrade to the site of intervention. (1) Excimer and Ho:YAG induce chronic arterial wall damage, which may result in accelerated restenosis. (2) Ho:YAG results in deeper and more extensive lesions than excimer. (3) Both lasers induce an initial vasodilation in the irradiated vessel which disappears at follow-up.

Kvasnicka, Jan; Geschwind, Herbert J.; Nakamura, Fumitaka; Asada, Masakatsu; Levame, Micheline; Bousbaa, Hassan

1993-06-01

81

Proton irradiation on materials  

NASA Technical Reports Server (NTRS)

A computer code is developed by utilizing a radiation transport code developed at NASA Langley Research Center to study the proton radiation effects on materials which have potential application in NASA's future space missions. The code covers the proton energy from 0.01 Mev to 100 Gev and is sufficient for energetic protons encountered in both low earth and geosynchronous orbits. With some modification, the code can be extended for particles heavier than proton as the radiation source. The code is capable of calculating the range, stopping power, exit energy, energy deposition coefficients, dose, and cumulative dose along the path of the proton in a target material. The target material can be any combination of the elements with atomic number ranging from 1 to 92, or any compound with known chemical composition. The generated cross section for a material is stored and is reused in future to save computer time. This information can be utilized to calculate the proton dose a material would receive in an orbit when the radiation environment is known. It can also be used to determine, in the laboratory, the parameters such as beam current of proton and irradiation time to attain the desired dosage for accelerated ground testing of any material. It is hoped that the present work be extended to include polymeric and composite materials which are prime candidates for use as coating, electronic components, and structure building. It is also desirable to determine, for ground testing these materials, the laboratory parameters in order to simulate the dose they would receive in space environments. A sample print-out for water subject to 1.5 Mev proton is included as a reference.

Chang, C. Ken

1993-01-01

82

Status of irradiations performed by testing and irradiation services for BNW as of August 13, 1967.  

National Technical Information Service (NTIS)

This report itemizes the irradiations performed by Testing and Irradiation Services for Battelle-Northwest. It lists the material being irradiated, awaiting disposition and material shipped during the month of August 1967.

L. V. Barker

1967-01-01

83

Status of irradiations performed by testing and irradiation services for BNW as of August 13, 1967  

Microsoft Academic Search

This report itemizes the irradiations performed by Testing and Irradiation Services for Battelle-Northwest. It lists the material being irradiated, awaiting disposition and material shipped during the month of August 1967.

1967-01-01

84

Status of irradiations performed by testing and irradiation services for BNW as of October 15, 1967.  

National Technical Information Service (NTIS)

This report itemizes the irradiations performed by Testing and Irradiation Services for Battelle-Northwest. It lists the materials being irradiated, awaiting disposition and materials shipped during the month of October 1967.

L. V. Barker

1967-01-01

85

Status of irradiations performed by testing and irradiation services for BNW as of October 15, 1967  

Microsoft Academic Search

This report itemizes the irradiations performed by Testing and Irradiation Services for Battelle-Northwest. It lists the materials being irradiated, awaiting disposition and materials shipped during the month of October 1967.

1967-01-01

86

Status of irradiations performed by testing and irradiation services for BNW as of March 10, 1968.  

National Technical Information Service (NTIS)

This report itemizes the irradiations performed by Testing and Irradiation Services for Battelle-Northwest. It lists the material being irradiated, awaiting disposition and material shipped during the report period. Specific data given is TISR No., Reques...

L. V. Barker

1968-01-01

87

Status of irradiations performed by Testing and Irradiation Services for BNW as of July 31, 1969.  

National Technical Information Service (NTIS)

This report itemizes the irradiations performed by Testing and Irradiation Services for Battelle-Northwest. It lists the material being irradiated, awaiting disposition and material shipped during the report period. Data are given in table form. Informati...

L. V. Barker

1969-01-01

88

Plasmodium falciparum: attenuation by irradiation  

SciTech Connect

The effect of irradiation on the in vitro growth of Plasmodium falciparum was investigated. The cultured malarial parasites at selected stages of development were exposed to gamma rays and the sensitivity of each stage was determined. The stages most sensitive to irradiation were the ring forms and the early trophozoites; late trophozoites were relatively insensitive. The greatest resistance was shown when parasites were irradiated at a time of transition from the late trophozoite and schizont stages to young ring forms. The characteristics of radiosensitive variation in the parasite cycle resembled that of mammalian cells. Growth curves of parasites exposed to doses of irradiation upto 150 gray had the same slope as nonirradiated controls but parasites which were exposed to 200 gray exhibited a growth curve which was less steep than that for parasites in other groups. Less than 10 organisms survived from the 10(6) parasites exposed to this high dose of irradiation; the possibility exists of obtaining radiation-attenuated P. falciparum.

Waki, S.; Yonome, I.; Suzuki, M.

1983-12-01

89

Irradiation Resistance of Multicomponent Alloys  

NASA Astrophysics Data System (ADS)

High-entropy alloys (HEAs) are characterized not only by high values of entropy but also by high atomic-level stresses originating from mixing of elements with different atomic sizes. Particle irradiation on solids produces atomic displacements and thermal spikes. The high atomic-level stresses in HEAs facilitate amorphization upon particle irradiation, followed by local melting and re-crystallization due to thermal spikes. We speculate that this process will leave much less defects in HEAs than in conventional alloys. For this reason, they may be excellent candidates as new nuclear materials. We discuss initial results of computer simulation on model binary alloys and an electron microscopy study on Zr-Hf-Nb alloys, which demonstrate extremely high irradiation resistance of these alloys against electron damage to support this speculation.

Egami, T.; Guo, W.; Rack, P. D.; Nagase, T.

2014-01-01

90

Gas retention in irradiated beryllium  

SciTech Connect

Helium (an inert gas) with low solubility in beryllium is trapped in irradiated beryllium at low temperatures (<100{degree}C) while the tritium generated may have some mobility and be released. The subject of tritium retention in irradiated beryllium within fusion reactor blankets is of considerable interest in their conceptual design. Results from experiments on three sets of irradiated beryllium specimens are examined in this paper. The beryllium specimens were irradiated at abut 75{degree}C in capsules to protect them from the cooling water. One set of samples was irradiated to {approximately}3 {times} 10{sup 22} n/cm{sup 2} (E > 1 MeV). In these samples the calculated helium generated was {approximately} 14,000 appm. They are described in terms of swelling, annealing, microstructure, and helium bubble behavior (size, density and mobility). A second sample was irradiated to {approximately}5 {times} 10{sup 22} n/cm{sup 2} (E > 1 MeV). In that one the calculated helium and tritium generated were {approximately}24,000 appm He and {approximately}3720 appm, and tritium content was examined in a dissolution experiment. Most of the tritium was released as gas to the glovebox indicating the generated tritium was retained in the helium bubbles. In a third set of experiments a specimen was examined by annealing at a succession of temperatures to more than 600{degree}C for tritium release. In the temperature range of 300--500{degree}C little release (0.01--0.4%) occurred, but there was a massive release at just over 600{degree}C. Theories of swelling appear to adequately describe bubble behavior with breakaway release occurring at high helium contents and at large bubble diameters. 8 refs., 6 figs.

Beeston, J.M.; Miller, L.G.; Longhurst, G.R. (EG and G Idaho, Inc., Idaho Falls, ID (USA)); Causey, R.A. (Sandia National Labs., Albuquerque, NM (USA))

1990-06-01

91

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

92

Irradiated icecreams for immunosuppressed patients  

NASA Astrophysics Data System (ADS)

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

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

2003-04-01

93

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

NASA Astrophysics Data System (ADS)

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

Lean, J.

2013-12-01

94

Hydrodésazotation de la pyridine sous pression atmosphérique catalysée par des oxynitrures de Ni, Mo, et des oxynitrures mixtes MoNi, MoPNi, AlNi et AlPNi  

NASA Astrophysics Data System (ADS)

Hydrodenitrogenation of pyridine has been realised, under atmospheric pressure, in the presence of oxynitride catalysts of molybdenum, nickel and their solid solutions as well as on mixed catalysts MoNi, MoPNi, AlNi and AlPNi. In all cases, the main reaction products are n-pentane and N-pentylpiperidine, at any conversion. Kinetic results suggest that the conversion of pyridine, on nickel oxynitride, proceeds through successive steps with hydrogenation as rate-limiting. Molybdenum oxynitride and Mo-Ni-N solid solutions tested in the temperature range 500 circC-450 circC, showed a good structural and catalytic stability, but a low catalytic activity. On the other hand, nickel oxynitride catalyst yielded higher activity at much lower temperatures (190 circC-250 circC). X-rays analysis indicates that the used catalyst was entirely reduced to metallic nickel, which is the active phase. Under the same experimental conditions, mixed catalysts are relatively less active but more selective than nickel oxynitride into n-pentane formation. La réaction d'hydrodésazotation de la pyridine a été réalisée, sous pression atmosphérique, en présence de catalyseurs oxynitrures de molybdène, de nickel et leurs solutions solides ainsi que sur les catalyseurs mixtes MoNi, MoPNi, AlNi et AlPNi. Dans tous les cas, les principaux produits de réaction observés sont le n-pentane et la N- pentylpipéridine, quel que soit le taux de conversion. Les résultats cinétiques obtenus en régime intégral, en présence de l'oxynitrure de nickel, suggèrent un schéma réactionnel successif où l'hydrogénation de la pyridine serait l'étape limitante. L'oxynitrure de molybdène et les solutions solides Mo-Ni-N, testés à des températures supérieures ou égales à 500 circC, ont montré une bonne stabilité catalytique et structurale mais une faible activité catalytique. En revanche, l'oxynitrure de nickel présente une activité catalytique plus importante à des températures de réaction beaucoup plus basses (190 circC 250 circC). Cependant, l'analyse aux rayons X du catalyseur usagé, indique qu'il est entièrement réduit à l'état métallique; ceci laisse supposer que le nickel métallique est la phase active. Dans les mêmes conditions expérimentales, les catalyseurs mixtes sont relativement moins actifs que l'oxynitrure de nickel, mais plus sélectifs vis-à-vis de la formation du n-pentane.

Elkamel, K.; Elidrissi, M.; Yacoubi, A.; Nadiri, A.; Abouarnadasse, S.

1998-11-01

95

Neutron irradiation damage in transition metal carbides  

NASA Astrophysics Data System (ADS)

Effects of neutron irradiation on the physical properties of light transition metal carbides, TiCx, VCx and NbCx, were examined, emphasizing the characterization of irradiation induced defects in the nonstoichiometric composition. TiC x irradiated with 14 MeV (fusion) neutrons showed higher damage rates with increasing C/Ti ( x) ratio. A brief discussion is made on "cascade damage" in TiCx irradiated with fusion neutrons. Two other carbides ( VCx and NbCx) were irradiated with fission reactor neutrons. The irradiation effects on VCx were not so simple, because of the complex irradiation behavior of "ordered" phases. For instance, complete disordering was revealed in an ordered phase, "V 8C 7", after an irradiation dose of 10 25 n/m 2.

Matsui, Hisayuki; Nesaki, Kouji; Kiritani, Michio

1991-03-01

96

Statistical criteria for characterizing irradiance time series.  

SciTech Connect

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

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

2010-10-01

97

Sterilization of Human Bone by Irradiation.  

National Technical Information Service (NTIS)

Over the years, irradiation sterilization has been the most widely used sterilization method and one of the most acceptable methods of decontaminating human tissue. It is the purpose of chapter to discuss what is known about the methodology of irradiation...

R. W. Bright J. D. Smarsh V. M. Gambill

1983-01-01

98

Food Irradiation Newsletter. V.13, no. 1.  

National Technical Information Service (NTIS)

The International Conference on the Acceptance, Control of, and Trade in Irradiated Food, jointly sponsored by FAO, IAEA, WHO and ITC-UNCTAD/GATT, Geneva, Switzerland, December 1988, recognized that (1) food irradiation has the potential to reduce the inc...

1989-01-01

99

Food Irradiation: What You Need to Know  

MedlinePLUS

... extend the shelf life of foods. Control of Insects – irradiation can be used to destroy insects in or on tropical fruits imported into the United States. Irradiation also decreases the need for other pest-control ...

100

Irradiation Softening in Pure Iron Single Crystals.  

National Technical Information Service (NTIS)

The characteristics of irradiation softening in Fe were studied. Results show that irradiation softening effect can be explained by the intrinsic mechanism, namely, the interaction of screw dislocations with randomly dispersed interstitials. At least some...

M. Meshii

1975-01-01

101

Pathological Effects of Thyroid Irradiation.  

National Technical Information Service (NTIS)

Therapeutic doses of X-rays to the thyroid region of children have been followed after some years by the development of thyroid neoplasms. Whereas the percent of cases of malignant neoplasms is small, the proportion of persons irradiated who develop nodul...

1966-01-01

102

Operation of the Irradiation Facilities.  

National Technical Information Service (NTIS)

In 1982, 48 companies utilized the 100kCi Co-60 irradiation facility for sterization of their medical products and food products such as gauze sponges, absorbent cotton, ginseng powder and etc. A total of 12,411 cartons of 44 different items of medical pr...

Y. S. Yoo H. W. Chung J. H. Jin S. C. Park H. S. Chang

1983-01-01

103

Food Irradiation: Solution or Threat?  

NSDL National Science Digital Library

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

1997-01-01

104

Fractionated Stereotactic Irradiation: Technical Implications  

Microsoft Academic Search

The biological rationale for fractionated radiotherapy treatment and the development of noninvasive head fixation systems have led to the increased use of fractionated stereotactic irradiation for intracranial lesions, especially with curative intent. The authors present an overview of the most common immobilization systems with special reference to the evaluation procedures to determine the precision of repositioning. For the different noninvasive

Martine Delannes; Jacques Bonnet; Sharon Beesley; Nicolas Daly-Schveitzer

1999-01-01

105

STRUCTURAL DEGRADATION OF IRRADIATED PROTEIN  

Microsoft Academic Search

Irradiated protein systems contain molecules in various stages of ; structurnl degradation Some of these degraded molecules are insoluble at their ; isoelectric point and on the basis of the conventional criterion will be ; described as denatured. Molecules in more moderately injured configrations can ; be detected since they denature more easily than the native. In order to study

C. A. Leone; H. Fricke

1958-01-01

106

Microwave Irradiation and Multicomponent Reactions  

Microsoft Academic Search

A common theme throughout drug discovery and process development is speed. With the emergence of combinatorial chemistry and high-speed parallel synthesis, multicomponent reactions (MCRs) have seen a resurgence of interest. MCRs are therefore becoming increasingly popular since they provide the possibility to introduce a large degree of chemical diversity in only one step! Microwave irradiation under controlled conditions has been

Jitender B. Bariwal; Jalpa C. Trivedi; Erik V. van der Eycken

2010-01-01

107

Ionic Conductivity in Irradiated KCl.  

National Technical Information Service (NTIS)

The ionic conductivity of X and gamma irradiated KCl single crystals has been studied between room temperature and 600 deg C. The radiation induced damage resulting in a decrease of the conductivity heals by thermal annealing in two steps which are at abo...

J. Vignolo Rubio

1979-01-01

108

[Ovarian irradiation in recurrent endometriosis].  

PubMed

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

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

2005-09-01

109

Solar Spectral Irradiance and Climate  

NASA Technical Reports Server (NTRS)

Spectrally resolved solar irradiance is recognized as being increasingly important to improving our understanding of the manner in which the Sun influences climate. There is strong empirical evidence linking total solar irradiance to surface temperature trends - even though the Sun has likely made only a small contribution to the last half-century's global temperature anomaly - but the amplitudes cannot be explained by direct solar heating alone. The wavelength and height dependence of solar radiation deposition, for example, ozone absorption in the stratosphere, absorption in the ocean mixed layer, and water vapor absorption in the lower troposphere, contribute to the "top-down" and "bottom-up" mechanisms that have been proposed as possible amplifiers of the solar signal. New observations and models of solar spectral irradiance are needed to study these processes and to quantify their impacts on climate. Some of the most recent observations of solar spectral variability from the mid-ultraviolet to the near-infrared have revealed some unexpected behavior that was not anticipated prior to their measurement, based on an understanding from model reconstructions. The atmospheric response to the observed spectral variability, as quantified in climate model simulations, have revealed similarly surprising and in some cases, conflicting results. This talk will provide an overview on the state of our understanding of the spectrally resolved solar irradiance, its variability over many time scales, potential climate impacts, and finally, a discussion on what is required for improving our understanding of Sun-climate connections, including a look forward to future observations.

Pilewskie, P.; Woods, T.; Cahalan, R.

2012-01-01

110

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; Ménager, Jérémie; Gouard, Sébastien; Maurel, Catherine; Guilloux, Yannick; Faivre-Chauvet, Alain; Morgenstern, Alfred; Bruchertseifer, Frank; Chérel, Michel; Davodeau, François; Gaschet, Joëlle

2014-04-01

111

Neutron Irradiation of LPE Bubble Domain Garnets  

Microsoft Academic Search

Five LPE iron garnets were irradiated in two steps to a total of 2 × 1015 n\\/cm2 (En > 10 keV). Samples included GdEr-, GdY-, GdYTm-, GdYYb- and GdYLa-IG's. Pre- and post-irradiation measurements were made of l, 4piMs, Ho, Hk and muw. A pre-irradiation simulation of ambient reactor conditions showed that the properties were not affected by these influences. Post-irradiation

R. S. Sery; H. R. Irons

1974-01-01

112

Neutron Irradiation of LPE Bubble Domain Garnets  

Microsoft Academic Search

Five LPE iron garnets were irradiated in two steps to a total of 2 × 1015 n?cm2 (En > 10 keV). Samples included GdEr-, GdY-, GdYTm-, GdYYb- and GdYLa-IG's. Pre- and post-irradiation measurements were made of ℓ, 4?Ms, Ho, Hk and ?w. A pre-irradiation simulation of ambient reactor conditions showed that the properties were not affected by these influences. Post-irradiation

R. S. Sery; H. R. Irons

1974-01-01

113

AGC1 Post Irradiation Examination Status  

Microsoft Academic Search

The Next Generation Nuclear Plant (NGNP) Graphite R&D program is currently measuring irradiated material property changes in several grades of nuclear graphite for predicting their behavior and operating performance within the core of new Very High Temperature Reactor (VHTR) designs. The Advanced Graphite Creep (AGC) experiment consisting of six irradiation capsules will generate this irradiated graphite performance data for NGNP

David Swank

2011-01-01

114

Mechanical response of proton beam irradiated nitinol  

Microsoft Academic Search

The present investigation deals with the study of mechanical behavior of proton beam irradiated nitinol at room temperature. The specimens in austenitic phase were irradiated over periods of 15, 30, 45 and 60 min at room temperature using 2 MeV proton beam obtained from Pelletron accelerator. The stress-strain curves of both unirradiated and irradiated specimens were obtained using a universal

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

2011-01-01

115

Research trends with food irradiation in Japan  

Microsoft Academic Search

Potatoes and onions are irradiated to prevent their germination for 8 ; months after harvest. Twenty-seven tons of potatoes were exposed to ⁶°Co ; gamma irradiation at a dose rate of 7 x 10⁴ R\\/hr. Potatoes irradiated with ; a dose of 7 to 15 Krads were stored for 8 months at room temperature, and were ; suitable market produce.

1973-01-01

116

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

117

Effect of microwave irradiation on TATB explosive.  

PubMed

Finished TATB (1,3,5-triamino-2,4,6-trinitrobenzene) explosive safety under 800W microwave irradiation was experimented. No burning, deflagration and detonation were observed during 30-min continuous irradiation and no remarkable change were observed after irradiation according to HPLC, particles size analysis, and differential thermal analysis. Wet TATB sampled from synthesis line was irradiated with microwave vacuum method and irradiated TATB was measured to accord with military standard specifications including appearance, moisture and volatile, chloride content, HPLC, mean particle size, DTA exothermic peak, ash, acetone soluble content, PH value, etc. Microwave vacuum desiccation was deemed laborsaving, energy-efficient, and practicable compared to conventional processing method. PMID:19324496

Yu, Weifei; Zhang, Tonglai; Huang, Yigang; Yang, Li; Li, Gang; Li, Haibo; Li, Jinshan; Huang, Hui

2009-09-15

118

Calculation of direct normal irradiation from global horizontal irradiation  

NASA Astrophysics Data System (ADS)

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

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

2012-10-01

119

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

120

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

121

Hydrazine degradation by ultrasonic irradiation.  

PubMed

The influence of pH on the degradation of hydrazine with a concentration of 0.1mmol/L was investigated under the stirring (300rpm) and ultrasonic irradiation conditions (200kHz, 200W) in the pH range of 1-9. It was found that the hydrazine degradation depended greatly upon pH under the ultrasonic irradiation condition, while it did not take place over the whole pH range under the stirring condition. Although it has been known that OH radicals and hydrogen peroxide are sonochemically formed from water, it was considered that the OH radicals played an important role of the hydrazine degradation, but not hydrogen peroxide. The pH dependence of the hydrazine degradation was discussed in terms of the relationship between the chemical structure and the basic dissociation constants of hydrazine. PMID:17513042

Nakui, Hiroyuki; Okitsu, Kenji; Maeda, Yasuaki; Nishimura, Rokurou

2007-07-31

122

Calculated strength of irradiated ferritics  

NASA Astrophysics Data System (ADS)

Effects of irradiation on dislocation recovery kinetics and strengthening have been calculated and compared to reported responses in Fe-2 14Cr-lMo steels. The analysis indicates that predicted interstitial loop growth causes increases in strength at 673 K that are comparable to measure increases in strength at 10 dpa. With increasing temperature, radiation softening was predicted as expected from experimental observations. The transition from hardening to softening was predicted to occur at temperatures about 50 K above the measured transition. A strong hardening effect was predicted from depleted zone accumulation at 673 K, but only when depleted zones were assumed to be unbiased microvoids. Radiation enhanced growth of Mo 2C precipitates were predicted to have an influence on hardening that was less than predicted for hardening caused by loop growth. At later stages of carbide evolution, irradiation softening may occur because of reduction in solid solution hardening and enhancement in carbide coarsening.

Simonen, E. P.

1985-08-01

123

Microwave Irradiation and Multicomponent Reactions  

NASA Astrophysics Data System (ADS)

A common theme throughout drug discovery and process development is speed. With the emergence of combinatorial chemistry and high-speed parallel synthesis, multicomponent reactions (MCRs) have seen a resurgence of interest. MCRs are therefore becoming increasingly popular since they provide the possibility to introduce a large degree of chemical diversity in only one step! Microwave irradiation under controlled conditions has been shown to be an invaluable technology since it often allows to dramatically reduce reaction times from days or hours to minutes or even seconds. Compound libraries can be rapidly synthesized in either a parallel or sequential way using this new, enabling technology. The current chapter highlights the application of microwave irradiation for MCRs during the last 4 years. More than 110 recent literature reports have been covered.

Bariwal, Jitender B.; Trivedi, Jalpa C.; van der Eycken, Erik V.

124

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

125

Overlay welding irradiated stainless steel  

NASA Astrophysics Data System (ADS)

An overlay technique developed for welding irradiated stainless steel may be important for repair or modification of fusion reactor materials. Helium, present due to (n,alpha) reactions, is known to cause cracking using conventional welding methods. Stainless steel impregnated with 3 to 220 appm helium by decay of tritium was used to develop a welding process that could be used for repair. The result was a gas metal arc weld overlay technique with low-heat input and low-penetration into the helium-containing material. Extensive metallurgical and mechanical testing of this technique demonstrated substantial reduction of helium embrittlement damage. The overlay technique was applied to irradiated 304 stainless steel containing 10 appm helium. Surface cracking, present in conventional welds made on the same steel at lower helium concentrations, was eliminated. Underbead cracking, although greater than for tritium charged and aged material, was minimal compared to conventional welding methods.

Kanne, W. R.; Chandler, G. T.; Nelson, D. Z.; Franco-Ferreira, E. A.

126

Learning Disabilities Following CNS Irradiation  

Microsoft Academic Search

Thirteen elementary school age children with acute leukemia who had received cranial irradiation with dosages between 1,800 and 4,800 rads a mean of 6.3 years earlier were evaluated for the presence of learning disorders. The authors utilized both psychometric and educational tests. The results were analyzed according to a graduated regressed standard score procedure and yielded the following diagnoses: mental

Kathryn Fogarty; Victoria Volonino; Jefferies Caul; Jan Rongey; Barbara Whitman; Dennis OConnor; Pasquale Accardo

1988-01-01

127

SORCE Solar Irradiance Data Products  

NASA Astrophysics Data System (ADS)

The Laboratory for Atmospheric and Space Physics (LASP) at the University of Colorado manages the SOlar Radiation and Climate Experiment (SORCE) Science Data System. This data processing system routinely produces Total Solar Irradiance (TSI) and Spectral Solar Irradiance (SSI) data products, which are formulated using measurements from the four primary instruments on board the SORCE spacecraft. The TIM instrument provides measurements of the TSI, whereas the SIM, SOLSTICE, and XPS instruments collectively provide measurements of the solar irradiance spectrum from 1 nm to 2400 nm (excluding 31-115 nm, which is measured by the SEE instrument on NASA's TIMED mission). Derived products, such as the Magnesium II Core-to-Wing Index which can be used for space weather applications, are also produced. The SORCE Science Data System utilizes raw spacecraft and instrument telemetry, calibration data, and other ancillary information to produce a variety of solar irradiance data products that have been corrected for all known instrumental and operational factors. Since launch of the SORCE spacecraft in January 2003, science processing algorithms have continued to mature, instrument calibrations (e.g. degradation corrections) have improved, and regularly updated versions of data products have been released. "Level 3" data products (time-averaged over daily and six-hourly periods and/or spectrally re-sampled onto uniform wavelength scales) are routinely produced and delivered to the public via the SORCE web site (http://lasp.colorado.edu/sorce/data/), and are archived at the Goddard Earth Sciences (GES) Data and Information Services Center (DISC). Native resolution "Level 2" products are also available for scientific studies. This poster provides an overview of the SORCE data processing system, summarizes the present state of the processing algorithms, describes the quality of the current SORCE data products, provides details on how to access SORCE science data, and presents future plans.

Lindholm, D. M.; Pankratz, C. K.; Knapp, B. G.; Meisner, R.; Fontenla, J.; Harder, J. W.; McClintock, W. E.; Kopp, G.; Snow, M.; Woods, T. N.

2008-12-01

128

Microwave Irradiation and Multicomponent Reactions  

Microsoft Academic Search

\\u000a \\u000a Abstract  A common theme throughout drug discovery and process development is speed. With the emergence of combinatorial chemistry and\\u000a high-speed parallel synthesis, multicomponent reactions (MCRs) have seen a resurgence of interest. MCRs are therefore becoming\\u000a increasingly popular since they provide the possibility to introduce a large degree of chemical diversity in only one step!\\u000a Microwave irradiation under controlled conditions has been

Jitender B. Bariwal; Jalpa C. Trivedi; Erik V. Van der Eycken

129

Total and spectral irradiance variations  

NASA Astrophysics Data System (ADS)

The Sun's electromagnetic radiation is the dominant energy input to the Earth system. It heats the land and ocean, maintains our atmosphere, generates clouds, and cycles the planet's water. Most physical processes connecting the Sun's radiation to the terrestrial environment are strongly wavelength dependent. Detailed knowledge of the Sun's spectral irradiance, including its wavelength dependent variability, is required to fully understand the solar influence on the Earth's atmosphere and climate. The Sun varies on all time scales from fractions of a second to months and years, and perhaps to millennia. Observations indicate that the variations are only a fraction of one percent in the visible and near infrared, but much larger in the ultraviolet and X-rays. These findings are compatible with a very stable photosphere, but with a solar atmosphere --- chromosphere, transition region and corona --- disturbed and activated by ever changing magnetic fields. This talk will review observations of total solar irradiance and spectral irradiance obtained during the past twenty-five years.

Rottman, G.

130

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

131

Proton Irradiation Study of GFR Candidate Ceramics  

SciTech Connect

This work investigated the microstructural response of ZrC, ZrN, TiN, and SiC irradiated with 2.6 MeV protons at 800ºC to a single dose in the range of 1.5 to 3.0 displacement per atom (dpa), depending on the material. The change of lattice constant evaluated using HOLZ patterns is not observed and is small when measured using XRD for the irradiated samples up to 1.5 dpa for 6H-SiC, and up to 3.0 dpa for ZrC and ZrN. In comparison to Kr ion irradiation at 800ºC to 10 dpa from the previous studies, the proton-irradiated ceramics at 3.0 dpa show less irradiation damage to the lattice structure. The irradiated ZrC exhibits faulted loops which are not observed in the Kr ion irradiated sample. The irradiated ZrN shows the least microstructural change from proton irradiation. The microstructure of 6H-SiC irradiated to 3.0 dpa consists of a black dot defect type at high density.

Jian Gan; Yong Yang; Clayton Dickson; Todd Allen

2009-05-01

132

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

PubMed

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

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

2002-09-25

133

Conformational changes of myosin by gamma irradiation  

NASA Astrophysics Data System (ADS)

Conformational and decompositional changes of bovine skeletal muscle myosin caused by gamma irradiation were studied for understanding the effects of irradiation treatment on myofibrillar proteins. Myosin solution and beef cuts were irradiated 0, 1, 3, 5 and 10 kGy. Competitive indirect enzyme linked immunosorbent assay (Ci-ELISA) showed that subunits of myosin were structurally modified with different patterns. Binding abilities of anti-myosin whole molecule and anti heavy meromyosin S-1 IgG, which were produced from rabbits, with irradiated myosin decreased in the same tendency depending upon the dose. Anti-light meromyosin IgG appeared to have the highest binding ability at 3 kGy. Irradiated beef cuts (?5 kGy) could be identified by Ci-ELISA. Myosin solution became increasingly turbid with increasing dose. Hydrophobicity of myosin solution also increased by irradiation. Electrophoretic patterns showed that the myosin heavy chain disappeared and new bands were generated at higher molecular weight ranges.

Lee, Ju.-Woon; Yook, Hong.-Sun; Lee, Kyong.-Haeng; Kim, Jae.-Hun; Kim, Woo.-Jung; Byun, Myung.-Woo

2000-05-01

134

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 600°C. 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, Nélida Lucia

2002-03-01

135

EPR Investigation of Irradiated Curry Powder  

NASA Astrophysics Data System (ADS)

Gamma-ray irradiated curry powder, a well priced oriental spice was investigated in order to establish the ability of EPR to detect the presence and time stability of free irradiation free-radicals. Accordingly, curry powder aliquots were irradiated with gradually increasing absorbed doses up to 11.3 kGy. The EPR spectra of all irradiated samples show the presence of al last two different species of free radicals, whose concentration increased monotonously with the absorbed doses. A 100° C isothermal annealing of irradiated samples has shown a differential reduction of amplitude of various components of the initial spectra, but even after 3.6 h of thermal treatment, the remaining amplitude represents no less then 30% of the initial ones. The same peculiarities have been noticed after more than one year storage at room temperature, all of them being very useful in establishing the existence of any previous irradiation treatment.

Duliu, O. G.; Ali, S. I.; Georgescu, R.

2007-04-01

136

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

137

(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

138

Enhanced oxygen precipitation in electron irradiated silicon  

Microsoft Academic Search

The precipitation of oxygen has been investigated for 2 MeV electron irradiated silicon samples, with irradiation doses 1015–1018 cm?2, at an annealing temperature of 900 °C for up to 444 h. The samples initially contained either different concentrations of the vacancy-oxygen (VO) center created at the irradiation, or the vacancy-dioxygen (VO2) center created by annealing at 350 °C after the

Tomas Hallberg; J. Lennart Lindström

1992-01-01

139

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.

140

Irradiation Testing of Ultrasonic Transducers  

SciTech Connect

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

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

2013-12-01

141

Safety Assurance for ATR Irradiations  

SciTech Connect

The Advanced Test Reactor (ATR) located at the Idaho National Laboratory (INL) is the world’s premiere test reactor for performing high fluence, large volume, irradiation test programs. The ATR has many capabilities and a wide variety of tests are performed in this truly one of a kind reactor, including isotope production, simple self-contained static capsule experiments, instrumented/controlled experiments, and loop testing under pressurized water conditions. Along with the five pressurized water loops, ATR may also have gas (temperature controlled) lead experiments, fuel boosted fast flux experiments, and static sealed capsules all in the core at the same time. In addition, any or all of these tests may contain fuel or moderating materials that can affect reactivity levels in the ATR core. Therefore the safety analyses required to ensure safe operation of each experiment as well as the reactor itself are complex. Each test has to be evaluated against stringent reactor control safety criteria, as well as the effects it could have on adjacent tests and the reactor as well as the consequences of those effects. The safety analyses of each experiment are summarized in a document entitled the Experiment Safety Assurance Package (ESAP). The ESAP references and employs the results of the reactor physics, thermal, hydraulic, stress, seismic, vibration, and all other analyses necessary to ensure the experiment can be irradiated safely in the ATR. The requirements for reactivity worth, chemistry compatibilities, pressure limitations, material issues, etc. are all specified in the Technical Safety Requirements and the Upgraded Final Safety Analysis Report (UFSAR) for the ATR. This paper discusses the ESAP process, types of analyses, types of safety requirements and the approvals necessary to ensure an experiment can be safely irradiated in the ATR.

S. Blaine Grover

2006-10-01

142

Irradiation effects in ferritic steels  

NASA Astrophysics Data System (ADS)

Since 1979 the Alloy Development for Irradiation Performance (ADIP) task funded by the US Department of Energy has been studying the 2-12Cr class of ferritic steels to establish the feasibility of using them in fusion reactor first wall/breeding blanket (FW/B) applications. The advantages of ferritic steels include superior swelling resistance, low thermal stresses compared to austenitic stainless steels, attractive mechanical properties up to 600°C. and service histories exceeding 100 000 h. These steels are commonly used in a range of microstructural conditions which include ferritic, martensitic. tempered martensitic, bainitic etc. Throughout this paper where the term "ferritic" is used it should be taken to mean any of these microstructures. The ADIP task is studying several candidate alloy systems including 12Cr-1MoWV (HT-9), modified 9Cr-1MoVNb, and dual-phased steels such as EM-12 and 2 {1}/{4}Cr-Mo. These materials are ferromagnetic (FM), body centered cubic (bcc), and contain chromium additions between 2 and 12 wt% and molybdenum additions usually below 2%. The perceived issues associated with the application of this class of steel to fusion reactors are the increase in the ductile-brittle transition temperature (DBTT) with neutron damage, the compatibility of these steels with liquid metals and solid breeding materials, and their weldability. The ferromagnetic character of these steels can also be important in reactor design. It is the purpose of this paper to review the current understanding of these bcc steels and the effects of irradiation. The major points of discussion will be irradiation-induced or -enhanced dimensional changes such as swelling and creep, mechanical properties such as tensile strength and various measurements of toughness, and activation by neutron interactions with structural materials.

Lechtenberg, Thomas

1985-08-01

143

Fuel and materials irradiation test program and post irradiation examination facilities in PNC  

Microsoft Academic Search

The current status of Japanese irradiation programs for fast reactor ; fuel and materials is described for the JOYO'' experimental fast reactor and ; MUNJU'' proto type fast reactor. The current status of PNC's post irradiation ; examination facilities are also described. (auth);

K. Uematsu; Y. Ishida; H. Kashihara; T. Kawata

1973-01-01

144

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

2010-10-01

145

Extraterrestrial Spectral Solar Irradiance Data for Modeling Spectral Solar Irradiance at the Earth's Surface.  

National Technical Information Service (NTIS)

This report describes the extraterrestrial (air mass zero, AMO) spectral solar irradiance data used by the Solar Energy Research Institute's Resource Assessment Branch in models to calculate spectral solar irradiance at the earth's surface. The report con...

C. Riordan

1987-01-01

146

The irradiation effects on zirconium alloys  

NASA Astrophysics Data System (ADS)

Pressure tube samples were irradiated under helium atmosphere in the TRIGA Steady State Research and Material Test Reactor of the Romanian Institute for Nuclear Research (INR). These samples are made of the Zr-2.5%Nb alloy used as structural material for the CANDU Romanian power reactors. After irradiation, mechanical tests were performed in the Post Irradiation Examination Laboratory (PIEL) to study the influence of irradiation on zirconium alloys mechanical behaviour. The tensile test results were used for structural integrity assessment. Results of the tests are presented. The paper presents, also, pressure tube structural integrity assessment.

Negut, Gh.; Ancuta, M.; Radu, V.; Ionescu, S.; Stefan, V.; Uta, O.; Prisecaru, I.; Danila, N.

2007-05-01

147

ISO 21348 - Process for determining solar irradiances  

NASA Astrophysics Data System (ADS)

A new international standard is being published by the International Standards Organization ISO The document ISO 21348 Space Environment natural and artificial -- Process for determining solar irradiances describes the process for representing solar irradiances We report on the content of the final version of this new standard Because solar irradiance measurements and modeling are constantly evolving through improved instrumentation measurement techniques and modeling capabilities the new standard has been written as a process-based standard to encourage development in solar irradiance determination The standard covers all representations of solar irradiances and is applicable to measurements reference spectra empirical models physics-based models as well as solar proxies and indices The purpose of the standard is to provide a common specification for all solar irradiances for use by space systems materials and environment users A solar irradiance product or specification is compliant with the standard if four criteria are followed First solar irradiances are reported at the minimum in SI units of Watts per square meter corrected to 1 AU Second the method of determining irradiances is documented for data collection processing archiving validation accuracy precision methodology and algorithm information Where applicable a description of proxies and independent data sets used in the derivation of empirical models including the rationale for proxy selection and the mathematical formulation for numerical models is

Tobiska, W.; Nusinov, A.

148

Data on total and spectral solar irradiance  

NASA Technical Reports Server (NTRS)

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

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

1983-01-01

149

Analytical screening studies on irradiated food packaging.  

PubMed

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

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

2014-01-01

150

Post irradiation testing of samples from the irradiation experiments PARIDE 3 and PARIDE 4  

Microsoft Academic Search

In order to study the influence of fast neutrons on the behaviour of high heat flux components for ITER, miniaturized samples have been neutron irradiated. Neutron fluences were 0.2 dpa in carbon\\/0.15 dpa in tungsten (irradiation campaign PARIDE 3) and 1 dpa in carbon\\/0.6 dpa in tungsten (irradiation campaign PARIDE 4). Irradiation temperatures were 200 °C approximately for all samples.

M. Roedig; W. Kuehnlein; J. Linke; D. Pitzer; M. Merola; E. Rigal; B. Schedler; E. Visca

2004-01-01

151

Progress of food irradiation in the United States  

Microsoft Academic Search

Irradiated foods have not yet made a significant impact in the United States marketplace. What progress has occurred to facilitate their commercialization? Irradiated produce has been sold in small quantities since 1992 and irradiated poultry was introduced in the marketplace in 1993. Federal inspection of irradiated commodities has settled into a regular routine.What must occur to further expand irradiated foods

D. D. Derr; D. L. Engeljohn; R. L. Griffin

1995-01-01

152

Short-term irradiation and post-irradiation examination of thermionic emitters  

Microsoft Academic Search

The technological adequacy of the thermionic emitters of the incore ; thermionic reactor (ITR) was tested in an irradiation program in the reactor FR ; 2, Karlsruhe. The irradiation capsule developed for this purpose is described in ; some detail. It was tested in a short-term irradiation experiment in which the ; emitters were exposed to a temperature of 1,860

Huebner

1973-01-01

153

Study on the surface performance of carbon fibres irradiated by ?-ray under different irradiation dose  

Microsoft Academic Search

The technology of high-energy irradiation is widely used in the field of material interface modification because of its high efficiency, energy conservation and environment friendliness. In this paper, ?-ray irradiation graft technology was used in order to enhance the surface performance of the carbon fibre (CF). The surface chemical elements and functional groups of untreated and irradiated CF were observed

Jun-Qing Li; Yu-Dong Huang; Shao-Yun Fu; Li-Hui Yang; Hai-tao Qu; Guang-shun Wu

2010-01-01

154

Correlations Between Total Solar Irradiance and Spectral Irradiances Using SORCE Measurements  

Microsoft Academic Search

The SOlar Radiation and Climate Experiment (SORCE) was launched in January 2003 to measure both total solar irradiance (TSI) and spectral solar irradiance (SSI). The available spectral irradiances are contiguous from 115 nm to 1600 nm with nearly daily coverage, providing useful inputs to climate models since the Earth's atmospheric response is highly wavelength dependent. By correlating these relatively recent

G. Kopp

2006-01-01

155

Charge dynamics in irradiated polymers  

NASA Astrophysics Data System (ADS)

Recent progress in the field of charge storage and charge transport in polymers irradiated with partially penetrating electron beams is discussed. The analytical model used to describe these phenomena takes the following physical parameters and processes into consideration: charge and energy deposition profiles, ohmic relaxation due to the radiation-induced conductivity, charge drift due to a finite carrier mobility, deep trapping without release, and trap filling due to a finite trap density. The model calculations show the effect of the various parameters on the shape of the charge distribution and on its motion. Experiments with the laser-induced pressure-pulse method on several high-resistivity polymers yield the location of the peak of the charge layers and their shape as function of injected charge density, time, and annealing conditions. The experimental results are interpreted with an analytical model and realistic values of the required physical parameters. Finally, conclusions about charge dynamics in irradiated polymers are drawn and compared with those of earlier investigations.

Sessler, G. M.

1992-10-01

156

Effect of re-irradiation by neutrons on mechanical properties of un-irradiated/irradiated SS316LN weldments  

NASA Astrophysics Data System (ADS)

Stainless steel of type SS316LN-IG (ITER Grade) is used for the branch pipeline connecting of the module coolant system and for other structures of ITER. One of the most important requirements for the branch pipeline connection is to recover various defects by welding. In the present study, characteristics of irradiated weldments were evaluated. SS316LN-IG specimens irradiated to helium contents of 3 and 10 appm He were prepared by the first neutron irradiation. Thereafter, the SS316LN-IG specimens with three different combinations of un-irradiation and irradiation were welded by a tungsten inert-gas (TIG) welding method. These weldments were re-irradiated at 150 °C up to a fast neutron fluence of about 7.5 × 10 24 n/m 2 ( E > 1 MeV). Tensile tests of the weldments and the base material were carried out at 20 and 150 °C after the re-irradiation. The results of the comparison before and after the re-irradiation showed that tensile properties of all weldment specimens with the different combinations were almost the same as those of the base materials.

Tsuchiya, K.; Shimizu, M.; Kawamura, H.; Kalinin, G.

2008-02-01

157

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

158

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

159

Irradiation effects on meat flavor: A review.  

PubMed

Irradiating fresh meat, even at low doses, can result in off-odors and flavors which have been described as rotten egg, bloody, fishy, barbecued corn, burnt, sulfur, metallic, alcohol or acetic acid. The odors vary with the type of meat, temperature during irradiation, oxygen exposure during and/or after the irradiation process, packaging and presence of antioxidative substances. Irradiation can induce formation of isooctane-soluble carbonyl compounds in the lipid fraction and low molecular weight, acid-soluble carbonyls in the protein fraction of meat. Increasing irradiation dose increases these compounds however, cooking reduces them. Among the volatile components, 1-heptene and 1-nonene are influenced most by irradiation dose, and aldehydes (propanal, pentanal, hexanal) are influenced most by packaging type (aerobic vs vacuum). Sulfur-containing volatiles formed from sulfur-containing compounds (primarily amino acids) also contribute to irradiation odor. Dimethyltrisulfide is one of the most potent off-odor compounds, contributing fishy, putrid odors, followed by bismethylthiomethane (sulfurous). Reducing the temperature during the irradiation process reduces the effects on odor/flavor because free radical generation and dispersion are reduced. Ultimately, radiolysis of water into free radical species (OH,H, H(3)0(+), e(aq)(-)) may be the initiators of both lipid oxidation breakdown products and sulfur-containing volatiles responsible for irradiation odor. Methods to decrease the detrimental effects of irradiation include oxygen exclusion (vacuum packaging), replacement with inert gases (nitrogen), addition of protective agents (antioxidants), and post-irradiation storage to allow flavor to return to near-normal levels (re-packaging or double packaging in oxygen permeable film). PMID:22063956

Brewer, M S

2009-01-01

160

Low Dose Irradiation Growth in Zirconium.  

National Technical Information Service (NTIS)

Low dose neutron irradiation growth in textured and recrystallized zirconium, is studied, at the Candu Reactors Calandria temperature (340 K) and at 77 K. It was necessary to design and build 1: A facility to irradiate at high temperatures, which was inst...

A. M. Fortis

1987-01-01

161

JMTR (Japan Materials Testing Reactor) Irradiation Handbook.  

National Technical Information Service (NTIS)

A wide variety of nuclear irradiation and post-irradiation experiments are available using the JMTR (Japan Materials Testing Reactor, 50 MW) and the multi-cell hot laboratory associated with the JMTR. In this Handbook, an application manual for conducting...

1983-01-01

162

METHODS OF POST-IRRADIATION EXAMINATION  

Microsoft Academic Search

The problems of planning and organization of an irradiation experiment ; are briefly discussed and then general technical problems are mentioned which ; arise from the necessity of handling irradiated highly radioactive specimens in ; heavily shielded cells. Special techniques and working methods, which are used ; for hot cell manipulation, are described in connection with some operations of ;

H. Schumacher; M. Stauffer

1963-01-01

163

Irradiation effects in high temperature superconductors.  

National Technical Information Service (NTIS)

Irradiation effects on T1- and Y-based high temperatures superconductors (HTS) are compared. Ion irradiation can enhance the critical current density (J(sub c)) at low fluences through the interaction of defects with the flux lattice, and at higher fluenc...

J. C. Barbour E. L. Venturini D. S. Ginley J. F. Kwak

1991-01-01

164

Microstructural evolution of proton irradiated T91  

Microsoft Academic Search

Understanding radiation effects in ferritic martensitic alloys is critical for their success in advanced reactor and transmutation systems. The objective of this work is to evaluate the microstructural and mechanical property changes in irradiated ferritic martensitic alloy T91. Irradiations were conducted with 2.0 MeV protons to doses of 3, 7, and 10 dpa at a dose rate of 2 ×

G. Gupta; Z. Jiao; A. N. Ham; J. T. Busby

2006-01-01

165

EPR Spectra of Some Irradiated Polycrystalline Perrhenates.  

National Technical Information Service (NTIS)

An EPR study of the paramagnetic centers formed by gamma , electron and neutron irradiation of the NaReO sub 4 and KReO sub 4 was made. In the EPR spectra of the powder samples irradiated gamma , with electrons and neutrons, the presence of three types of...

N. G. Zaitseva M. Constantinescu R. Georgescu O. Constantinescu

1978-01-01

166

Tensile Properties of Irradiated Tzm and Tungsten.  

National Technical Information Service (NTIS)

The effect of neutron irradiation on the elevated temperature tensile properties of TZM and tungsten has been experimentally determined. Specimens were irradiated at a temperature of approximately 720 exp 0 F to fluences of 0.4 and 0.9 x 10 exp 22 n/cm ex...

J. M. Steichen

1975-01-01

167

Positron Trapping in Heavily Irradiated Semiconductors.  

National Technical Information Service (NTIS)

Vacancy processes are studied in several heavily irradiated semiconductors. Specimens are ZnTe, CdTe, CdTe (In), InP, InP (Cr), InP (Zn) and Ge. Irradiations are made at 20 K using a 3 MeV Van de Graaff electron accelerator. Doses are 4 x 10 sup 18 e sup ...

P. Moser J. L. Pautrat C. Corbel P. Hautojarvi

1985-01-01

168

AFRRI Cobalt Whole-Body Irradiator.  

National Technical Information Service (NTIS)

The AFRRI cobalt irradiator contains two sets of sources, allowing for either unilateral or simultaneous bilateral irradiation of large animals or objects. With a loading of 25 kCi of 60Co, exposure rates up to 400 R/minute are possible. The exposure rate...

D. M. Verrelli R. E. Carter

1973-01-01

169

TSIS: The Total Solar Irradiance Sensor  

NASA Astrophysics Data System (ADS)

The Total Solar Irradiance Sensor (TSIS) is a dual-instrument package that will acquire solar irradiance in the next decade on the National Polar-orbiting Operational Environmental Satellite System (NPOESS). Originally de-manifested during the 2006 NPOESS restructuring, TSIS was restored following a decision by the NPOESS Executive Committee earlier this year because of its critical role in determining the natural forcings of the climate system and the high priority given it by the 2007 Earth Science Decadal Survey. TSIS is comprised of the Total Irradiance Monitor, or TIM, which measures the total solar irradiance (TSI) that is incident at the boundaries of the atmosphere; and the Spectral Irradiance Monitor, or SIM, which measures solar spectral irradiance (SSI) from 200 nm to 2400 nm (96 percent of the TSI). The TSIS TIM and SIM are heritage instruments to those currently flying on the NASA Solar Irradiance and Climate Experiment (SORCE). Both were selected as part of the TSIS because of their unprecedented measurement accuracy and stability, and because both measurements are essential to constraining the energy input to the climate system and interpreting the response of climate to external forcing. This paper will describe those attributes of TSIS which uniquely define its capability to continue the 30-year record of TSI and to extend the new 5-year record of SSI. The role of the solar irradiance data record in the present climate state, as well as in past and future climate change, will also be presented.

Sparn, T.; Pilewskie, P.; Harder, J.; Kopp, G.; Richard, E.; Fontenla, J.; Woods, T.

2008-12-01

170

Physical modeling of spectral irradiance variations  

Microsoft Academic Search

In this paper we introduce the Solar Radiation Physical Modeling (SRPM) methods and show its application to the modeling of spectral irradiance variations observed by the Spectral Irradiance Monitor (SIM) onboard SORCE. For the modeling we produce a set of seven physical models for features observed on the solar atmosphere. These models account for the available mid spatial and temporal-resolution

J. Fontenla; G. Harder

2005-01-01

171

Rethinking satellite-based solar irradiance modelling  

Microsoft Academic Search

Accurate solar irradiance data are not only of particular importance for the assessment of the radiative forcing of the climate system, but also absolutely necessary for efficient planning and operation of solar energy systems. Within the European project Heliosat-3, a new type of solar irradiance scheme is developed. This new type will be based on radiative transfer models (RTM) using

R. W. Mueller; K. F. Dagestad; P. Ineichen; M. Schroedter-Homscheidt; S. Cros; D. Dumortier; R. Kuhlemann; J. A. Olseth; G. Piernavieja; C. Reise; L. Wald; D. Heinemann

2004-01-01

172

RETHINKING SATELLITE BASED SOLAR IRRADIANCE MODELLING  

Microsoft Academic Search

Accurate solar irradiance data are not only of particular importance for the assessment of the radiative forcing of the climate system, but also absolutely necessary for an efficient planning and operation of solar energy systems. Within the European project Heliosat-3 a new type of solar irradiance scheme is developed. This new type will be based on radiative transfer models (RTM)

R. W. Mueller; K. F. Dagestad; R. Kuhlemann; J. A. Olseth; C. Reise; M. Schroedter; L. Wald; D. Heinemann

173

Luminescence in Electron Irradiated Cadium Sulphide.  

National Technical Information Service (NTIS)

Electron irradiation induced changes in both the photo- and cathodo-luminescence spectra of high purity CdS platelets have been monitored over a wave-length range from 4800A to 2 micrometers. The irradiations were all performed near 10K using beam energie...

C. N. Elsby J. M. Meese

1974-01-01

174

Identification of irradiated apples for phytosanitary purposes  

NASA Astrophysics Data System (ADS)

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

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

2009-07-01

175

Irradiation Effects on Reactor Structural Materials.  

National Technical Information Service (NTIS)

This report, covering research for the period 1 November 1964 - 31 January 1965, includes the following: (1) results of simultaneous irradiation of five heavy section plates of A302-B steel, (2) comparative irradiation of Charpy-V specimens of weld heat a...

L. E. Steele J. R. Hawthorne C. Z. Serpan E. P. Klier H. E. Watson

1965-01-01

176

Irradiation in combination with other preservation techniques  

Microsoft Academic Search

Irradiation has the potential to improve the microbiological safety and quality of many foods. However the dose which can be applied, and hence the extent of microbial kill, can be limited by undesirable changes in flavour, appearance and texture. Low dose irradiation in combination with other preservation techniques can be a practical solution in these cases and some would argue

Margaret Patterson

1996-01-01

177

Fundamental irradiation studies on vanadium alloys  

SciTech Connect

A joint experiment on the irradiation response of simple vanadium alloys has been initiated under the auspices of the DAFS and BES progams. Specimen fabrication is nearly complete and the alloys are expected to be irradiated in lithium in FFTF-MOTA Cycles 7 and 8.

Loomis, B.A.; Garner, F.A.; Ermi, A.M.

1985-05-01

178

Mechanical response of proton beam irradiated nitinol  

NASA Astrophysics Data System (ADS)

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

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

2011-01-01

179

Hafnium radioisotope recovery from irradiated tantalum  

Microsoft Academic Search

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

Wayne A. Taylor; David J. Jamriska

2001-01-01

180

Spectral Irradiance of Daylight at Durban.  

National Technical Information Service (NTIS)

An apparatus and method used to measure the spectral irradiance of daylight on a horizontal plane in the 295-775 nm wavelength region are described. Both global and diffuse sky irradiances were measured over a period of approximately 12 months. The result...

C. J. Kok A. N. Chalmers

1978-01-01

181

Virological Investigations on Irradiated Sewage Sludge.  

National Technical Information Service (NTIS)

The virusinactivating activity of a Co sub 60 -irradiation pilot plant at Geiselbullach/Munich was to be examined. We investigated 16 impure sewage water, 15 purified sewage water, 32 raw sladge samples, 62 digested sludge samples before irradiation, 52 d...

C. Epp

1980-01-01

182

Thermoluminscence of irradiated herbs and spices  

Microsoft Academic Search

Several types of herbs and spices from the local market were irradiated with different doses of gamma radiations. Doses varied from a few kilograys to 10 kilograys. Thermoluminescence of the irradiated samples and their controls was investigated. For the same type of herb or spice glow curves of different magnitudes, corresponding somewhat to the doses given, were obtained from the

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

1994-01-01

183

Irradiation creep in structural materials at ITER operating conditions.  

National Technical Information Service (NTIS)

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 fro...

M. L. Grossbeck

1994-01-01

184

21 CFR 179.25 - General provisions for food irradiation.  

Code of Federal Regulations, 2010 CFR

... true General provisions for food irradiation. 179.25 Section 179.25 Food...FOR HUMAN CONSUMPTION (CONTINUED) IRRADIATION IN THE PRODUCTION, PROCESSING AND HANDLING...179.25 General provisions for food irradiation. For the purposes of §...

2010-01-01

185

21 CFR 179.25 - General provisions for food irradiation.  

Code of Federal Regulations, 2010 CFR

... false General provisions for food irradiation. 179.25 Section 179.25 Food...FOR HUMAN CONSUMPTION (CONTINUED) IRRADIATION IN THE PRODUCTION, PROCESSING AND HANDLING...179.25 General provisions for food irradiation. For the purposes of §...

2009-04-01

186

Recovery process of neutron-irradiated vanadium alloys in post-irradiation annealing treatment  

NASA Astrophysics Data System (ADS)

Experiments to determine the influence of post-irradiation annealing on the mechanical properties and microstructures of neutron-irradiated V-4Cr-4Ti alloys were conducted. Two groups of specimens (as-irradiated specimens and specimens which underwent the post-irradiation annealing treatment) were subjected to tensile tests at room temperature and 773 K. Post-irradiation annealing experiments carried out over periods of up to 50 h were used to restore strength and ductility. As annealing time was extended, ductility was recovered up to 5% at 50 h anneal; however irradiation hardening was not recovered completely. Microstructural changes due to post-irradiation annealing corresponded to the amount that yield stress increased in tensile behavior in the irradiated specimen. The recovery in ductility was likely caused by the dissolution of interstitial impurities from defect clusters and dislocation cores produced by neutron irradiation during post-irradiation anneal treatment. A 3% elongation recovery in V-4Cr-4Ti alloys was achieved by annealing at 773 K for 20 h in a vacuum for neutron-irradiated samples at low temperature.

Fukumoto, K.; Iwasaki, M.; Xu, Q.

2013-11-01

187

Microbiological decontamination of natural honey by irradiation  

NASA Astrophysics Data System (ADS)

Degree of microbiological decontamination, organoleptic and physico-chemical properties of natural honeys were investigated after radiation treatment. Seven kinds of honeys were irradiated with the beams of 10 MeV electrons from a 10 kW linear accelerator "Elektronika 10-10" at the dose 10 kGy. It was shown, that after irradiation, the total count of aerobic and anaerobic bacteria and moulds decrease by 99%. The antibiotic value in investigated honeys increased in turn from 1.67 to 2.67 after irradiation. Such factors and parameters of investigated honeys as their consistency, content of water and saccharose, acidity, the diastase and 5-HMF values were not changed significantly after irradiation. Decontamination by irradiation is a process which allows us to obtain high microbiological purity of honeys. It is especially needed, when honeys are used in surgical treatment of injuries and in nutrition of babies with food deficiency.

Migda?, W.; Owczarczyk, H. B.; K ?dzia, B.; Ho?derna-K ?dzia, E.; Madajczyk, D.

2000-03-01

188

Relief of vasospasm by intravascular ultraviolet irradiation  

NASA Astrophysics Data System (ADS)

We investigated the photovasorelaxation with intravascular transluminal irradiation using in vivo model. A 2.5 Fr. catheter was inserted in the femoral artery of a rabbit under anesthesia. A 400 micrometers diameter quartz fiber was inserted through the catheter. The catheter was withdrawn from the distal end to the proximal end of the exposed femoral artery without laser irradiation in order to observe the mechanical dilation by the procedure. The femoral artery lumen was irradiated by a Helium-Cadmium(He-Cd) laser (wavelength; 325 nm) with 8 mW through the fiber during 30 s. We carried out that the laser irradiation produced vasorelaxation (185% on the average) compared with mechanical vasodilation (150% on the average) with angiography. The results suggest that intravascular transluminal irradiation with low-power UV laser might be applicable to the relief of acute arterial vasospasm.

Nakai, Kanji; Morimoto, Yuji; Ito, Hirotaka; Kominami, Kimito; Matsuo, Hirotaka; Arai, Tsunenori; Kikuchi, Makoto

1998-05-01

189

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

190

Emulation of neutron irradiation effects with protons: validation of principle  

Microsoft Academic Search

This paper presents the results of the irradiation, characterization and irradiation assisted stress corrosion cracking (IASCC) behavior of proton- and neutron-irradiated samples of 304SS and 316SS from the same heats. The objective of the study was to determine whether proton irradiation does indeed emulate the full range of effects of in-reactor neutron irradiation: radiation-induced segregation (RIS), irradiated microstructure, radiation hardening

J. T Busby; T. Allen; E. A Kenik; A. Jensson; S. M Bruemmer; J. Gan; A. D Edwards; P. M Scott; P. L Andreson

2002-01-01

191

Effect of gamma-irradiation on ripening papaya pectin  

Microsoft Academic Search

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

Min Zhao; James Moy; Robert E. Paull

1996-01-01

192

Historical Variations in Solar UV Irradiance  

NASA Astrophysics Data System (ADS)

Satellite measurements of solar UV variability have been made by at least fifteen different instruments since 1978. While it is difficult to keep a single UV irradiance instrument operating throughout a complete solar cycle, many of these instruments (Nimbus-7 SBUV, SME, NOAA-9 SBUV/2, NOAA-11 SBUV/2, UARS SUSIM, UARS SOLSTICE) were able to observe both maximum and minimum irradiance levels during either rising or declining phases of solar activity. Comparisons of these published results for solar cycles 21, 22, and 23 show consistent solar cycle irradiance changes at key wavelengths for terrestrial effects (e.g. 205 nm, 240 nm) within instrumental uncertainties. All historical data sets also show the same relative spectral dependence in the ultraviolet for both short-term (rotational) and long-term (solar cycle) variations. Empirical solar irradiance models that employ multiple proxy data sets to represent spectral irradiance produce long-term solar UV variations that are in good agreement with merged observational data through 2005. Recent UV irradiance data from the SORCE mission covering the declining phase of Cycle 23 present a different picture of long-term solar variations, with significantly larger temporal changes and different spectral dependence. We present comparisons of the SORCE irradiance data with previous solar UV observations and current model predictions. Scaling factors for use with solar UV proxy indexes have been derived from SORCE SIM and SORCE SOLSTICE data during 2004-2005. These scale factors, based on short-term irradiance variations, agree very well with results derived from concurrent NOAA-17 SBUV/2 and UARS SUSIM measurements. The 2004-2005 scale factors are consistent with previously derived scale factors that produce calculated long-term irradiance changes in good agreement with observations. The SORCE long-term solar UV irradiance results, corresponding to the early part of the mission, are consistent with undercorrection of instrument response changes during the first few years of SORCE measurements.

DeLand, M. T.

2011-12-01

193

RERTR-7 Irradiation Summary Report  

SciTech Connect

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

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

2011-12-01

194

Status of irradiations performed by fuel and target irradiation technology for BNW as of August 31, 1969.  

National Technical Information Service (NTIS)

This report itemizes the irradiations performed by Testing and Irradiation Services for Battelle-Northwest. It lists the materials being irradiated, awaiting disposition and material shipped during the report period. The data are given in table form. Info...

L. V. Barker

1969-01-01

195

Irradiation growth in zirconium and its alloys  

NASA Astrophysics Data System (ADS)

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

Rogerson, A.

1988-10-01

196

Influence of microwave irradiation on enzyme kinetics  

NASA Astrophysics Data System (ADS)

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

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

2009-09-01

197

Physical modeling of spectral irradiance variations  

NASA Astrophysics Data System (ADS)

In this paper we introduce the Solar Radiation Physical Modeling (SRPM) methods and show its application to the modeling of spectral irradiance variations observed by the Spectral Irradiance Monitor (SIM) onboard SORCE. For the modeling we produce a set of seven physical models for features observed on the solar atmosphere. These models account for the available mid spatial and temporal-resolution observations of the main quiet-Sun and active-region features at visible and IR wavelengths. The computed, very high spectral resolution, spectra from each of these models at ten different positions on the disk are used together with image analysis of Precision Solar Photometric Telescope (PSPT) images to produce an image mask and the absolute spectral irradiance that corresponds to each set of PSPT images. After convolving the spectra with the specific instrumental profile one can directly compare these synthetic spectra with spectral irradiance observations. The combination of the models matches the observed solar irradiance measured by SOLSPEC within the combined observational and computational accuracy, but it is on the high side. Also, the spectral irradiance visible and IR are computed and convolved to SIM resolution for comparison or irradiance variations.

Fontenla, J.; Harder, G.

198

Organic chemistry by irradiation in space  

NASA Astrophysics Data System (ADS)

The irradiation of grains and/or ices by particles from solar or stellar winds, as well as cosmic rays, induces the synthesis of molecular species. The authors have shown by in-situ infrared spectroscopy of irradiated samples that this chemistry may be responsible for the presence of organic compounds in a large variety of astrophysical sites such as: lunar and asteroidal regoliths, cometary nuclei, rings and satellites of outer planets, circumstellar shells, interstellar clouds. The authors present their experimental results concerning the nature and efficiency of C and N irradiation chemistry, and give plausible astrophysical implications.

Bibring, J.-P.; Rocard, F.

199

Hyperparathyroidism following head and neck irradiation  

SciTech Connect

A history of head and neck irradiation in childhood or adolescence was found in 22 of 130 patients with primary hyperparathyroidism compared with only 12 of 400 control patients. Among 200 patients with a known history of childhood irradiation, biochemical or surgical evidence of hyperparathyroidism was found in ten, a prevalence of 5%. This is at least 30 times the prevalence of hyperparathyroidism in the general population. The data indicate that head and neck irradiation should be regarded as an important risk factor in the subsequent development of hyperparathyroidism.

Rao, S.D.; Frame, B.; Miller, M.J.; Kleerskoper, M.; Block, M.A.; Parfitt, A.M.

1980-02-01

200

Oxygen intake in ion irradiated fullerene films  

NASA Astrophysics Data System (ADS)

The present work reports the change in the oxygen content in energetic ion irradiated fullerene films. The oxygen contents in irradiated films have been studied using on-line elastic recoil detection analysis (ERDA) and off-line X-ray photo electron emission (XPS) and nuclear reaction analysis (NRA) techniques. The XPS and NRA techniques show that the oxygen content increases with ion fluence, whereas on-line ERDA measurements reveal that the oxygen content decreases with ion fluence. These experiments give clear evidence that oxygen content in irradiated films increases after exposure to the atmospheric oxygen.

Kumar, Amit; Khan, S. A.; Kumar, Manvendra; Agarwal, D. C.; Singh, Fouran; Tripathi, A.; Govind; Shivaprasad, S. M.; Salomon, J.; Pichon, L.; Pivin, J. C.; Avasthi, D. K.

2008-04-01

201

RERTR-12 Insertion 2 Irradiation Summary Report  

SciTech Connect

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

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

2012-09-01

202

Measuring Degradation Rates Without Irradiance Data  

SciTech Connect

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

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

2011-02-01

203

Technique of Locoregional Irradiation in Breast Cancer  

PubMed Central

In medicine, one modality of treatment cannot be replaced by another unless the new method is equal, if not superior, to the existing one. Currently, much is heard about using irradiation alone for the treatment of early breast cancer. Uniform irradiation of the breast, underlying chest wall, and the regional lymph nodes is a complex procedure and unless done properly, a geographical miss of the tumor and/or unnecessary irradiation of adjacent normal structures can occur, leading to inferiority of the treatment method. ImagesFigure 1Figure 2Figure 3Figure 6Figure 7Figure 8

Kumar, P. Pradeep; Henschke, Ulrich K.

1977-01-01

204

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

205

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

206

Tensile properties of irradiated nuclear grade pressure vessel welds for the third HSST irradiation series  

SciTech Connect

The Heavy Section Steel Technology (HSST) Program conducted a series of experiments to investigate the effect of neutron irradiation on the fracture toughness of nuclear pressure vessel materials. Four welds of A 508 class 2 steel were examined in this Third HSST Irradiation Series. The welds were fabricated according to ''early'' (pre-1972) light-water reactor weld practice (i.e., copper-coated electrodes). As part of this study, tensile properties were measured after irradiation to 2 to 10 x 10/sup 22/ neutrons/m/sup 2/ (E > 1 MeV) at temperatures between 250 and 290/sup 0/C. Strength properties of all four welds increased with exposure to irradiation. Yield strength was more sensitive to irradiation than was ultimate strength. Tensile ductility was not affected significantly by exposure to irradiation.

McGowan, J.J.

1985-03-01

207

Swelling in previously neutron-irradiated commercial Fe-Cr-Ni based alloys under electron irradiation  

NASA Astrophysics Data System (ADS)

In order to avoid the artifacts which result because void swelling and precipitate stability are not accelerated to the same degree during radiation damage simulation experiments, a series of electron irradiation experiments were performed on commercial alloy specimens which were first irradiated in-reactor. This procedure is intended to establish a microstructure typical of in-reactor behavior which is then irradiated at accelerated rates in order to provide prediction of behavior to high fluence in-reactor on a reduced time scale. Neutron-irradiated specimens of fully-aged and solution treated Nimonic ? PE16, 20% cold-worked AISI 310 stainless steel and aged A-286 were electron irradiated at 500-700°C in the HVEM to determine the effect of reactor-conditioning on the simulation of void swelling at high neutron fluences. For aged PE16 it was found that the swelling behavior under electron irradiation was unaffected by prior neutron irradiation. Specimens from four different reactor temperature/fluence conditions showed the same temperature-dependent swelling rates in the HVEM irradiations. The swelling behavior of aged PE16. A-286 and cold-worked 310 was also consistent with previous results on specimens which were not previously neutron irradiated. However, reactor conditioning did alter the swelling response of solution-treated PE16 under electron irradiation, and this effect is attributed to the irradiaton-enhanced precipitation of ?' which occurs in-reactor. It is concluded that void and dislocation substructures generated in-reactor exert only second order control over void swelling during electron irradiation. Reactor conditioning expriments can be better described as temperature change experiments, providing that the alloy in question remains stable during neutron irradiation.

Gelles, D. S.; Thomas, L. E.; Laidler, J. J.

1982-08-01

208

Processing Irradiated Beryllium For Disposal  

SciTech Connect

The purpose of this research was to develop a process for decontaminating irradiated beryllium that will allow it to be disposed of through normal radwaste channels. Thus, the primary objectives of this ongoing study are to remove the transuranic (TRU) isotopes to less than 100 nCi/g and remove {sup 60}Co, and {sup 137}Cs, to levels that will allow the beryllium to be contact handled. One possible approach that appears to have the most promise is aqueous dissolution and separation of the isotopes by selected solvent extraction followed by precipitation, resulting in a granular form for the beryllium that may be fixed to prevent it from becoming respirable and therefore hazardous. Beryllium metal was dissolved in nitric and fluorboric acids. Isotopes of {sup 241}Am, {sup 239}Pu, {sup 85}Sr, and {sup 137}Cs were then added to make a surrogate beryllium waste solution. A series of batch contacts was performed with the spiked simulant using chlorinated cobalt dicarbollide (CCD) and polyethylene glycol diluted with sulfone to extract the isotopes of Cs and Sr. Another series of batch contacts was performed using a combination of octyl (phenyl)-N,N-diisobutylcarbamoylmethylphosphine oxide (CMPO) in tributyl phosphate (TBP) diluted with dodecane for extracting the isotopes of Pu and Am. The results indicate that greater than 99.9% removal can be achieved for each isotope with only three contact stages.

T. J. Tranter; R. D. Tillotson; N. R. Mann; G. R. Longhurst

2005-11-01

209

Irradiation Effects on Reactor Structural Materials.  

National Technical Information Service (NTIS)

The report, covering research for the period 1 November 1972 - 31 January 1973, includes: (1) postirradiation notch ductility assessments of austenitic stainless steel weldments, (2) studies of fatigue resistance of neutron irradiated cold worked Type 304...

L. E. Steele

1973-01-01

210

Neutron irradiation effects on YBCO single crystals.  

National Technical Information Service (NTIS)

Fast neutron irradiation of YBCO single crystals has proved to result in significant increases of magnetization hysteresis and consequently an enhancement of critical current densities. In addition, shifts of the irreversibility line have been observed. B...

F. M. Sauerzopf H. P. Wiesinger H. W. Weber G. W. Crabtree

1991-01-01

211

Microstructural development in irradiated vanadium alloys  

SciTech Connect

Three simple vanadium alloys, V-5Al, V-1Ni, and V-2Ti-1Ni have been examined to determine the effects of fast neutron irradiation on microstructural evolution. Specimens were irradiated in EBR II at temperatures in the range 425 to 600{degrees}C to doses of 15 and 31 dpa. Each alloy responded very differently to irradiation. All V-5Al specimens were generally void-free and contained high densities of coherent precipitates, and moderate densities of network dislocations. Swelling was much higher in V-1Ni. Voids were uniformly distributed, but with widely varying shape and size. Precipitation of two types also developed. The response in V-2Ti-1Ni was intermediate to that of the other two alloys. Irradiation produced extensive precipitation of thin rods and a moderate density of large voids often associated with much larger precipitate particles. The dislocation structure strongly interacted with the rod precipitate particles.

Gelles, D.S. [Pacific Northwest Lab., Richland, WA (United States); Stubbins, J.F. [Illinois Univ., Urbana, IL (United States)

1993-09-01

212

Food Irradiation: Is It Safe and Wholesome?  

ERIC Educational Resources Information Center

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

Rebus, Shirley

1990-01-01

213

Thermoluminescence properties of irradiated chickpea and corn  

NASA Astrophysics Data System (ADS)

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

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

2008-02-01

214

Effect of Diethylhydroxylamine on Smog Chamber Irradiations.  

National Technical Information Service (NTIS)

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 hydroca...

L. T. Cupitt E. W. Corse

1979-01-01

215

Swift heavy ion irradiation of diamond powder  

NASA Astrophysics Data System (ADS)

Sub-micrometer sized diamond powder was irradiated with 1.4 GeV uranium ions at fluences of 5 × 1012, 1 × 1013 and 8 × 1013 ions/cm2. The resulting structure of the irradiated diamond powder was investigated by synchrotron X-ray diffraction (XRD), Raman scattering and transmission electron microscopy. The high-resolution XRD measurements show that the diamond unit cell parameter increases with irradiation, and the unit cell volume increases by about 1.3‰ for the highest fluence. However, no peak broadening was observed and an ion-induced sharpening was evident after irradiation. Raman, TEM and EELS analysis confirmed that the diamond undergoes a radiation-induced transformation to a graphite-like carbon.

Zhang, Fuxiang; Lang, Maik; Zhang, Jiaming; Ewing, Rodney C.

2012-09-01

216

Spermatogonial Stem Cell Renewal Following Irradiation.  

National Technical Information Service (NTIS)

The spermatogonial cell renewal system can maintain function and a steady level of cell population for relatively long periods of continuous low-level irradiation indicating that there does not appear to be a serious accumulation, over many generations, o...

J. I. Fabrikant

1979-01-01

217

Irradiation Growth of Zircaloy (LWBR Development Program).  

National Technical Information Service (NTIS)

A model of irradiation growth of Zircaloy is presented based on two new mechanisms: (1) the direct production of interstitial dislocation loops accompanied by Seeger zones in the primary damage event, and (2) accelerated, nonrecoverable strain due to the ...

H. J. Willard

1982-01-01

218

Irradiation Effects on Reactor Structural Materials.  

National Technical Information Service (NTIS)

The report includes the following: (1) properties of steels irradiated in the reactors having significantly different neutron moderating characteristics, (2) development and verification of a damage function for correlation of radiation embrittlement in s...

L. E. Steele J. R. Hawthorne C. Z. Serpan H. E. Watson R. A. Gray

1969-01-01

219

Wear-resistant polytetrafluoroethylene via electron irradiation  

SciTech Connect

The sliding wear and friction behavior of irradiation-modified PTFE (by 10 MeV electrons in ambient air) against polished stainless steel is studied. Steady-state wear rate is shown to decrease monotonically by more than three orders of magnitude as the dose of the irradiation is increased from 0 to 30 Mrad. Friction initially increases with increasing dose, reaching a miximum value at 5 Mrad, then decreases with subsequent increases in dose, attaining a value similar to that of unirradiated PTFE at 30 Mrad. Hardness monotonically increases with increasing dose; however, irradiated PTFE was not found to abrasively damage the steel countersurface as many wear-resistant particle-filled PTFE composites do. Wear reduction is accomplished as debris production transforms from that of numerous large plate-like debris for unirradiated PTFE to that of very fine debris for irradiated PTFE. 26 refs., 6 figs.

Blanchet, T.A.; Peng, Y.L. [Aeronautical Engineering and Mechanics, Troy, NY (United States)

1996-06-01

220

Nitrogen vacancy complexes in nitrogen irradiated metals.  

National Technical Information Service (NTIS)

Gas desorption and positron annihilation techniques have been employed to study the evolution of nitrogen associated defects in nitrogen irradiated metals: Fe, Ni, Mo and W. Nitrogen in these metals has a rather high affinity to vacancy type defects. The ...

A. Veen K. T. Westerduin H. Schut E. J. E. Melker B. J. Thijsse

1996-01-01

221

FMIT - The Fusion Materials Irradiation Test Facility.  

National Technical Information Service (NTIS)

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...

D. J. Liska

1980-01-01

222

Effectiveness of Irradiation in Killing Pathogens.  

National Technical Information Service (NTIS)

United States Environmental Protection Agency regulations include gamma ray irradiation of sludge as an approved Process to Further Reduce Pathogens (PFRP) prior to land application. Research at Sandia National Laboratories on pathogen inactivation in slu...

J. G. Yeager, R. L. Ward

1980-01-01

223

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

224

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

225

Irradiation processing of potatoes, onions and garlic.  

National Technical Information Service (NTIS)

In this report, studies have been conducted on irradiation preservation of potatoes, onions and garlic involving different varieties, harvesting season and storage life. As a result of these investigations, optimum conditions were established for each cro...

M. Jan A. Starr M. Wahid A. Ahmad I. Khan

1992-01-01

226

Low Cycle Fatigue of Irradiated LMFBR Materials.  

National Technical Information Service (NTIS)

A review of low cycle fatigue data on irradiated LMFBR materials was conducted and extensive graphical representations of available data are presented. Representative postirradiation tensile properties of annealed 304 and 316 SS are selected and employed ...

L. D. Blackburn

1976-01-01

227

Applicability of the Sunna dosimeter for food irradiation control  

Microsoft Academic Search

The quick development concerning the commercial application of food irradiation in the USA recently resulted in growing marketing of irradiated red meat as well as irradiated fresh and dried fruits. These gamma and electron irradiation technologies require specific dosimetry systems for process control. The new version of the Sunna dosimeter has been characterized in gamma, electron and bremsstrahlung radiation fields

A. Kovács; M. Baranyai; L. Wojnárovits; S D. Miller; Mark K. Murphy; William L. Mclaughlin; I. Slezsák

2002-01-01

228

Workload foreseen for the IFMIF Post Irradiation Examination Facility  

Microsoft Academic Search

The workload for the Post Irradiation Examination Facility during the operation of IFMIF is evaluated in this paper based on the users’ specifications. The foreseen irradiation and Post Irradiation Examination programmes presented in this paper are based on the IFMIF specifications proposed by IFMIF users’ community, available irradiation volumes in the test modules and materials properties required to compile the

J. Molla; M. Yamamoto; A. Polato; M. Soldaini; H. Takeuchi; E. Wakai

2011-01-01

229

Irradiation tests report of the 30th cycle in 'JOYO'.  

National Technical Information Service (NTIS)

This report summarizes the operating and irradiation data of the experimental reactor 'JOYO' 30th cycle, and estimates the 31st cycle irradiation condition. Irradiation tests in the 30th cycle are as follows: (1) B-type irradiation rig (B9). (a) High burn...

1998-01-01

230

Irradiation tests report of the 31st cycle in 'JOYO'.  

National Technical Information Service (NTIS)

This report summarizes the operating and irradiation data of the experimental reactor 'JOYO' 31st cycle, and estimates the 32nd cycle irradiation condition. Irradiation tests in the 31st cycle are as follows: (1) B-type irradiation rig (B9). (a) High burn...

1998-01-01

231

Validation of gamma irradiator controls for quality and regulatory compliance  

Microsoft Academic Search

Since 1978 the U.S. Food and Drug Administration (FDA) has had both the legal authority and the Current Good Manufacturing Practice (CGMP) regulations in place to require irradiator owners who process medical devices to produce evidence of Irradiation Process Validation. One of the key components of Irradiation Process Validation is the validation of the irradiator controls. However, it is only

Rorry B. Harding; Francis J. A. Pinteric

1995-01-01

232

Control of stored-product pests by irradiation  

Microsoft Academic Search

The present review deals with the effects of irradiation on some aspects of the biology of major stored-product pests, namely mortality, stages of development, reproductive organs and reproductive potential, histology of the gut, factors influencing irradiation and the synergism of irradiation with other control agents. It also reports on the irradiation effects on stored commodities. Further guidelines for future research

MAHBUB Hasan; Ataur Rahman Khan

1998-01-01

233

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

234

Irradiation Creep Behavior of Vanadium Alloys during Neutron Irradiation in a Liquid Metal Environment  

NASA Astrophysics Data System (ADS)

The manufacturing process of creep specimens and an irradiation technique in a liquid metal environment for in-pile and creep measurements of irradiated samples are established for highly purified V-4Cr-4Ti, NIFS-HEAT alloys. Irradiation experiments with sodium-enclosed irradiation capsules in JOYO and lithiumenclosed irradiation capsules in HFIR-17J were conducted using pressurized creep tubes. From thermal creep experiments, the activation energy of creep deformation using pressurized creep tubes was determined to be 210 kJ/mol·K, the creep stress factor was 4.9 for an 800°C creep test, and its mechanism was determined to be a climb-assisted glide of dislocation motion. It was found that the creep strain rate exhibited a linear relationship with effective stress up to 150 MPa from 425 to 600°C under JOYO and HFIR irradiation. The activation energy of irradiation creep was estimated to be 46 kJ/mol·K. No significant difference in irradiation creep behavior between the liquid sodium and liquid lithium environments was observed. A set of essential physical data of irradiation creep properties was obtained for V-4Cr-4Ti alloys.

Fukumoto, Kenichi; Narui, Minoru; Matsui, Hideki; Nagasaka, Takuya; Muroga, Takeo

235

Post-irradiation soft tissue sarcoma  

Microsoft Academic Search

From 1975 to 1993, 11 of 375 patients treated for soft tissue sarcoma presented with post-irradiation sarcoma. The mean time interval between irradiation therapy and onset of the second neoplasm was 15.8 years (4–31 years). The total radiation dosage ranged from 12 to 60 Gy with a mean of 40 Gy. All patients had complete staging including CT or MRI

C. Bloechle; M. Peiper; R. Schwarz; S. Schroeder; C. Zornig

1995-01-01

236

Effects of hadron irradiation on scintillating fibers  

Microsoft Academic Search

Trackers based on scintillating-fiber technology are being considered by the Solenoidal Detector Collaboration at SSC and the DO collaboration at Fermilab. Some 600 fibers in the Fermilab Tevatron CO area were irradiated, thereby obtaining a hadronic irradiation at realistic rates. Four-meter-long samples of ten Bicron polystyrene-based fibre types, maintained in air, dry nitrogen, argon, and vacuum atmospheres within stainless-steel tubes,

B. Abbott; D. Adams; T. Armstrong; M. Atac; A. Baumbaugh; B. Baumbaugh; M. Binkley; S. Bird; J. Bishop; N. Biswas; A. D. Bross; C. Buchanan; N. Cason; R. Chaney; D. Chrisman; M. Chung; D. Cline; G. Collins; M. Corcoran; D. Davis; R. Davies; J. Elias; H. Fenker; E. Fenyves; D. Finley; G. W. Foster; H. Goldberg; H. Hammack; A. Hasan; S. Heppelmann; J. Jaques; R. Jesik; J. Kauffman; R. Kehoe; C. Kelley; M. Keely; V. Kenney; R. Kephart; C. Kim; D. Koltick; J. Kolonko; J. Kubic; R. A. Lewis; J. Losecco; B. Lowery; J. Marchant; R. McIlwain; S. Margulies; H. Mendez; H. Miettenen; R. Moore; B. Oh; J. Orgeron; J. Passaneau; A. Pla-Dalmau; C. Rivetta; R. Ruchti; R. Scalise; J. Schmitz; W. Shephard; E. Shibata; J. Skeens; G. A. Smith; J. Solomon; J. Thomas; S. Tkaczyk; W. Toothacker; F. Vaca; D. Vandergriff; R. Wagner; J. Warchol; M. Wayne; J. Whitmore

1993-01-01

237

Phase transformations in neutron-irradiated Zircaloys  

Microsoft Academic Search

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., ZrâO and cubic-ZrOâ particles approximately 2 to 10 nm in size. By means of a weak-beam dark-field ''2-1\\/2D-microscopy'' technique,

Chung

1986-01-01

238

Microstructural evolution of proton irradiated T91  

Microsoft Academic Search

Understanding radiation effects in ferritic–martensitic alloys is critical for their success in advanced reactor and transmutation systems. The objective of this work is to evaluate the microstructural and mechanical property changes in irradiated ferritic–martensitic alloy T91. Irradiations were conducted with 2.0MeV protons to doses of 3, 7, and 10dpa at a dose rate of 2×10?5dpa\\/s and at temperatures of 400°C,

G. Gupta; Z. Jiao; A. N. Ham; J. T. Busby

2006-01-01

239

Temperature distribution in tissue during laser irradiation  

Microsoft Academic Search

Summary During irradiation with an Ar+- and Kr+-laser the temperature rise in living and dead tissue was measured in various depths. The contribution of the blood flow to the heat transport during irradiation was found to be small. The influence of the different depths of penetration and backscattering at the blue-green Ar+- and the red Kr+-radiation was investigated. The measurements

J. Eichler; J. Knof; H. Lenz; J. Salk; G. Schäfer

1978-01-01

240

Determinants of skin sensitivity to solar irradiation  

Microsoft Academic Search

Background: Acute effects of UV irradiation include UV-induced erythema. Sunlight plays an important role in the development of skin cancer. Several predictive factors of UV-induced erythema could also be predictive for skin cancer.Objective: Our objective was to quantitatively assess phenotypical and nutritional determinants of sensitivity to UV irradiation, as assessed by the minimal erythema dose (MED).Design: We conducted a cross-sectional

W M R Broekmans; A. A. Vink; E. Boelsma; W. A. A. Klöpping-Ketelaars; L. B. M. Tijburg; P van't Veer; G van Poppel; A. F. M. Kardinaal; AFM Kardinaal

2003-01-01

241

Unilateral lung hyperlucency after mediastinal irradiation  

SciTech Connect

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

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

1988-04-01

242

[Total body irradiation: techniques and main indications].  

PubMed

The radiotherapy department at Salah Azaïz institute had started, in March 2000, a new sophisticated technique of irradiation consisting in total body irradiation (TBI). TBI is used in many preparative regimens before bone marrow transplantation in the treatment of haematological malignancies. TBI aims to destroy immunocompetent tissues in order to avoid graft rejection and to eradicate residual tumor cells. In this article, we review different TBI techniques and its main indications. We also describe the acute and late effects of TBI. PMID:16370205

Kochbati, Lotfi; Besbes, Mounir; Frikha, Hatem; Sellami, Dalila; Gargouri, Walid; Ben Ammar, Chiraz Nasr; Ben Aissia, Ridha; Benna, Farouk; Damak, Hedi; Maalej, Mongi

2005-10-01

243

Current status of accelerated partial breast irradiation  

Microsoft Academic Search

Accelerated partial breast irradiation (APBI) is a radiotherapy method used in breast-conserving therapy. In APBI, the tumor\\u000a bed is topically irradiated over a short period after breast-conserving surgery. The fundamental concept underlying APBI is\\u000a that more than 70% of ipsilateral breast tumor recurrence occurs in the neighborhood of the original tumor, and that hypofractionated\\u000a radiotherapy can be applied safely when

Michihide Mitsumori; Masahiro Hiraoka

2008-01-01

244

Fission Reactor Irradiation Tests of Bolometer  

NASA Astrophysics Data System (ADS)

A Bolometer, which is a calorimeter to measure energy deposition rate on its surface, and is composed of a gold meander on Muscovite mica thin plate, was irradiated in a Japan Materials Testing Reactor (JMTR), up to 0.1dpa, below 150C. Performance of the bolometer was evaluated in-situ during JMTR irradiation. Also, post-irradiation examination was carried out on the irradiated bolometer. The swelling of Muscovite was less than 0.3% after irradiation up to 2.2×1023n/m2 fast neutron fluence. No explicit deformation of the thin plates was recognized. The bolometer showed good performance under irradiation, but a large increase of electrical resistance of the gold meander was observed. This could be explained by introduction of about 50% mercury (Hg) atoms in the gold meander by nuclear transmutation, which made gold thin film brittle and also introduced a strong internal stress in the gold film, resulting in the exfoliation of the gold film from its Muscovite mica substrate.

Narui, M.; Yamasaki, M.; Shikama, T. T.; Nishitani, T.; Reichle, R.; Yamamoto, S.; Kasai, S.; Hodgson, E. R.

2003-06-01

245

Measurement and analysis of diffuse solar irradiance  

NASA Astrophysics Data System (ADS)

Measurements of the diffuse irradiance on a horizontal surface using a continuous tracking occulting disc and a pyranometer have been examined for cloudless days. The part of the diffuse component that is blocked by the occulting disc (circumsolar component) is analyzed with respect to the aerosol optical depth at a wavelength of 500 nanometers, solar zenith angle, and precipitable water. The magnitude of the circumsolar component is determined from the direct normal irradiance measured with a pyrheliometer, aerosol optical depth and precipitable water measured with a Volz sun photometer, and direct normal irradiance calculated from a direct beam model. The model was used to estimate only the direct beam over the same spectral interval as measured by the pyrheliometer. The computed component is subtracted from the measured direct normal irradiance and multiplied by the cosine of the solar zenith angle. The difference is an approximate value of the circumsolar irradiance on a horizontal surface. It is found that the circumsolar irradiance is a maximum for a small solar zenith angles, low aerosol optical depths, and small amounts of precipitable water.

Baker, C. B.

246

Measurement and analysis of diffuse solar irradiance  

SciTech Connect

Measurements of the diffuse irradiance on a horizontal surface using a continuous tracking occulting disc and a pyranometer have been examined for cloudless days. The part of the diffuse component that is blocked by the occulting disc (circumsolar component) is analyzed with respect to the aerosol optical depth at a wavelength of 500 nanometers, solar zenith angle, and precipitable water. The magnitude of the circumsolar component is determined from the direct normal irradiance measured with a pyrheliometer, aerosol optical depth and precipitable water measured with a Volz sun photometer, and direct normal irradiance calculated from a direct beam model. The pyrheliometer measures the direct beam as well as the circumsolar component. The model was used to estimate only the direct beam over the same spectral interval as measured by the pyrheliometer. The computed component is subtracted from the measured direct normal irradiance and multiplied by the cosine of the solar zenith angle. The difference is an approximate value of the circumsolar irradiance on a horizontal surface. It is found that the circumsolar irradiance is a maximum for small solar zenith angles, low aerosol optical depths, and small amounts of precipitable water. The largest change occurred for an increase in aerosol optical depth from .153 to .337, a solar zenith angle of 35/sup 0/, and 0.5 precipitable centimeters of water. The circumsolar component decreased by 17% and the measured diffuse increased by 50%.

Baker, C.B.

1983-01-01

247

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.

248

Inert matrix fuel behaviour in test irradiations  

NASA Astrophysics Data System (ADS)

Among others, three large irradiation tests on inert matrix fuels have been performed during the last five years: the two irradiation tests IFA-651 and IFA-652 in the OECD Halden Material Test Reactor and the OTTO irradiation in the High Flux Reactor in Petten. While the OTTO irradiation is already completed, the other two irradiations are still ongoing. The objectives of the experiments differ: for OTTO, the focus was on the comparison of different concepts of IMF, i.e. homogeneous fuel versus different types of heterogeneous fuel. In IFA-651, single phase yttria stabilized zirconia (YSZ) doped with Pu is compared with MOX. In IFA-652, the potential of calcia stabilized zirconia (CSZ) as a matrix with and without thoria is evaluated. The design of the three experiments is explained and the current status is reviewed. The experiments show that the homogeneous, single phase YSZ-based or CSZ-based fuel show good and stable irradiation behaviour. It can be said that homogeneous stabilized zirconia based fuel is the most promising IMF concept for an LWR environment. Nevertheless, the fuel temperatures were relatively high due to the low thermal conductivity, potentially leading to high fission gas release, and must be taken into account in the fuel design.

Hellwig, Ch.; Streit, M.; Blair, P.; Tverberg, T.; Klaassen, F. C.; Schram, R. P. C.; Vettraino, F.; Yamashita, T.

2006-06-01

249

Thermoluminscence of irradiated herbs and spices  

NASA Astrophysics Data System (ADS)

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

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

1994-07-01

250

Improvement of physical properties of soybeans by gamma irradiation  

NASA Astrophysics Data System (ADS)

Physical properties of gamma-irradiated soybeans were evaluated at different temperatures by determining water absorption pattern and cooking characteristics of the sample. Irradiation at 2.5-10 kGy caused the reduction of soaking time in soybeans by 2-5 hours and the increase of hydration capacity of 10-20%, respectively, compared to the non-irradiated control at 20°C. The activation energy for water absorption was lower in irradiated soybeans than in the non-irradiated control. Irradiation at 2.5-10 kGy caused the reduction of cooking time in soybeans by 30-60% compared to the non-irradiated control and the cooking rate constant of irradiated samples was higher about 2 times than that of the non-irradiated control. The irradiation efficacy on physical quality improvement was also recognized in the stored soybeans for one year at room temperature.

Byun, Myung-Woo; Kwon, Joong-Ho; Mori, Tomohiko

1993-07-01

251

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

SciTech Connect

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

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

2011-12-01

252

Removal of carbon-14 from irradiated graphite  

NASA Astrophysics Data System (ADS)

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

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

2014-08-01

253

POST-IRRADIATION EXAMINATION OF APPR FUEL ELEMENT IRRADIATION PROGRAM SPECIMENS  

Microsoft Academic Search

APPR-type dispersion fuel element specimens containing temperature to ; respective burnups of approximately 50, 20, and 20% of uranium with no evidence ; of gross dimensional changes or loss of structural integrity. Blistering and\\/or ; core cracking has occurred when sections of 17.9 wt.% UOâ specimens ; irradiated to burnups over 40% of uranium were subjected to post-irradiation ; annealing

Richt

1959-01-01

254

Post-irradiation experiments on physical, thermal and microstructural properties on neutron-irradiated ceramics.  

National Technical Information Service (NTIS)

This summary report describes the post-irradiation experiments of physical, thermal and microstructural properties of neutron-irradiated various ceramics, which are expected to be applied to the in-core materials of an Advanced Fast Breeder Reactor in nea...

T. Yano

1998-01-01

255

Simultaneous measurement of irradiation, temperature and reflectivity on hot irradiated surfaces  

NASA Astrophysics Data System (ADS)

Conversion of solar energy into chemical fuels has been a field of intense research for many years. It is usually attempted as a thermochemical reaction under highly concentrated solar irradiation, e.g. in a solar furnace. Special interest has been addressed to the question of whether concentrated light drives the reaction differently than heat. One effect of irradiation might be a decrease of the reaction temperature. To observe such an influence it is important to monitor the chemical process and the surface temperature of the sample under irradiation. In this paper we propose a method to measure the temperature, the irradiation and the reflectivity/emissivity distribution on an irradiated sample surface simultaneously. We first outline the computational background of the method and discuss its accuracy. We then report on laboratory measurements as well as on experiments performed in a solar furnace.

Schubnell, M.; Tschudi, H. R.

1995-06-01

256

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

257

Irradiation effect of yttria-stabilized zirconia by high dose dual ion beam irradiation  

NASA Astrophysics Data System (ADS)

Yttria-stabilized zirconia (YSZ) is irradiated with 2.0-MeV Au2+ ions and 30-keV He+ ions. Three types of He, Au, Au + He (successively) ion irradiation are performed. The maximum damage level of a sequential dual ion beam implanted sample is smaller than single Au ion implanted sample. A comparable volume swelling is found in a sequential dual ion beam irradiated sample and it is also found in a single Au ion implanted sample. Both effects can be explained by the partial reorganization of the dislocation network into weakly damaged regions in the dual ion beam implanted YSZ. A vacancy-assisted helium trapping/diffusion mechanism in the dual ion beam irradiated condition is discussed. No phase transformation or amorphization behavior happens in all types of ion irradiated YSZ.

Zhang, Yan-Wen; Wang, Xu; Liu, Shi-Yi; Tang, Mei-Xiong; Zhao, Zi-Qiang; Zhang, Peng; Wang, Bao-Yi; Cao, Xing-Zhong

2014-06-01

258

The volume effect in irradiated mouse colorectum  

NASA Astrophysics Data System (ADS)

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

Skwarchuk, Mark William

1997-11-01

259

Mutation induced with ion beam irradiation in rose  

NASA Astrophysics Data System (ADS)

The effects of mutation induction by ion beam irradiation on axillary buds in rose were investigated. Axillary buds were irradiated with carbon and helium ion beams, and the solid mutants emerged after irradiation by repeated cutting back. In helium ion irradiation, mutations were observed in plants derived from 9 buds among 56 irradiated buds in 'Orange Rosamini' and in plants derived from 10 buds among 61 irradiated buds in 'Red Minimo'. In carbon ion, mutations were observed in plants derived from 12 buds among 88 irradiated buds in 'Orange Rosamini'. Mutations were induced not only in higher doses but also in lower doses, with which physiological effect by irradiation was hardly observed. Irradiation with both ion beams induced mutants in the number of petals, in flower size, in flower shape and in flower color in each cultivar.

Yamaguchi, H.; Nagatomi, S.; Morishita, T.; Degi, K.; Tanaka, A.; Shikazono, N.; Hase, Y.

2003-05-01

260

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; Gómez, J A; Kinoshita, A; Calandreli, I; Tfouni, E; Baffa, O

2013-12-01

261

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

262

Neoplasms in young dogs after perinatal irradiation  

SciTech Connect

For a study of the life-time effects of irradiation during development, 1,680 beagles were given single, whole-body exposures to /sup 60/Co gamma-radiation at one of three prenatal (preimplantation, embryonic, and fetal) or at one of three postnatal (neonatal, juvenile, and young adult) ages. Mean doses were 0, 0.16, or 0.83 Gy. For comparison with data on childhood cancer after prenatal irradiation, examination was made of tumors occurring in young dogs in this life-span experiment. Up to 4 years of age, 18 dogs had neoplasms diagnosed, 2 of these being in controls. Four dogs that were irradiated in the perinatal (late fetal or neonatal) period died of cancers prior to 2 years of age. This risk was of significant increase compared to the risks for other experimental groups and for the canine population in general. Overall, 71% (5 of 7) of all cancers and 56% (10 of 18) of all benign and malignant neoplasms seen in the first 4 years of life occurred in 29% (480 of 1680) of the dogs irradiated in the perinatal period. These data suggest an increased risk for neoplasia after perinatal irradiation in dogs.

Benjamin, S.A.; Lee, A.C.; Angleton, G.M.; Saunders, W.J.; Miller, G.K.; Williams, J.S.; Brewster, R.D.; Long, R.I.

1986-08-01

263

Carotid artery disease following external cervical irradiation.  

PubMed Central

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

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

1981-01-01

264

Irradiation induced field fluctuations in graphite  

NASA Astrophysics Data System (ADS)

In irradiated porous medium, the presence of voids drastically reduces the electrical and mechanical strength of the system, as strong load enhancements occur following charge accumulation near the voids, leading to field emission or electric breakdown. The present work examines the charge accumulation and electric field distribution throughout charged particles irradiated porous matrix. Our objective is to show in a simple, but a quantitative manner, how hot spots develop in flawed sample with a possibility for coupling the heat enhancement produced under conditions where static electric fields are present back to problems of a safety concern such as the sudden release of the energy stored in neutron irradiated graphite. Spatial fluctuations of the local electric fields developed in graphite, following particle irradiation, are studied numerically using suitable Monte Carlo calculations. The present method is different from the conventionally used methods to realistically describe electric breakdown formation through charge inhomogeneities that we believe to be the most important physical implications. It is shown that the spatial distributions of the fields exhibit sharp peaks and strong fluctuations. Compared to unflawed material, field intensity enhancement reaches several orders of magnitude. The irradiated graphite seems to develop configurations typical of percolating composite materials where excess fields develop nonlinear susceptibilities that lead to new physical effects.

Salah, H.; Benouali, N.

2013-03-01

265

Effect of neutron irradiation on vanadium alloys  

SciTech Connect

Neutron-irradiated vanadium alloys were evaluated for their susceptibility to irradiation hardening, helium embrittlement, swelling, and residual radioactivity, and the results were compared with those for the austenitic and ferritic stainless steels. The VANSTAR-7 and V-15Cr-5Ti alloys showed the greatest hardening between 400 and 600/sup 0/C while V-3Ti-1Si and V-20Ti had lower values that were comparable to those of ferritic steels. The V-15Cr-5Ti and VANSTAR-7 alloys were susceptible to helium embrittlement caused by the combination of weakened grain boundaries and irradiation-hardened grain matrices. Specimen fractures were entirely intergranular in the most severe instances of embrittlement. The V-3Ti-1Si and V-20Ti alloys were more resistant to helium embrittlement. Except for VANSTAR-7 irradiated to 40 dpa at 520/sup 0/C, all of the vanadium alloys exhibited low swelling that was similar to the ferritic steels. Swelling was greater in specimens that were preimplanted with helium using the tritium trick. The vanadium alloys clearly exhibit lower residual radioactivity after irradiation than the ferrous alloys.

Braski, D.N.

1986-01-01

266

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

267

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

268

Pathogenesis of irradiation-induced cognitive dysfunction.  

PubMed

Neurocognitive dysfunction is a common sequela of cranial irradiation that is especially severe in young children. The underlying mechanisms of this disorder have not been described. The present review describes the role of the hippocampus and the anatomically related cortex in memory function and its marked susceptibility to ischemic and hypoxic injury. Based on studies of animal models of human amnesia and histopathological findings in the irradiated brain, the neurocognitive sequela of cranial irradiation can be seen to be mediated through vascular injury, resulting in ischemia and hypoxia in the hippocampal region. Recognition of the site and mechanisms of this injury may lead to the development of techniques to minimize the risks. PMID:8938210

Abayomi, O K

1996-01-01

269

Neutron irradiated beryllium: tensile strength and swelling  

NASA Astrophysics Data System (ADS)

Four different species of beryllium: S-200F (vacuum hot pressed, 1.2 wt% BeO), S-200FH (hot isostatic pressed, 0.9 wt% BeO); S-65 (vacuum hot pressed, 0.6 wt% BeO) and S-65H (hot isostatic pressed, 0.5 wt% BeO) are fabricated by Brush Wellman. Three batches of the berylliums are investigated, a neutron irradiated batch, a thermal control batch and a reference batch. Neutron irradiation is performed at nominal temperature conditions of 200, 400 and 600°C up to a fluence of 1.5 × 10 25 n m -2 ( En ? 1 MeV). Based on the tensile tests results, the S-65 VHP and the S-200 HIP show slightly higher elongation and strength after irradiation. Based on the swelling determination, S-200 swells less than S-65. In conclusion, the S-200 HIP might tentatively be selected.

Moons, Frans; Sannen, Leo; Rahn, August; Van De Velde, José

1996-10-01

270

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

Schröder, Sven; Surmann, J P

2006-11-01

271

Irradiation Is it Consumer-Friendly?  

NSDL National Science Digital Library

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

Anantheswaran, Swamy

2000-01-01

272

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

273

Irradiation behavior of pyrolytic silicon carbide. [HTGR  

SciTech Connect

Fuel particles for the High-Temperature Gas-Cooled Reactor (HTGR) contain a layer of pyrolytic silicon carbide to act as a miniature pressure vessel and primary fission-product barrier. Optimization of the SiC with respect to fuel performance involves four areas of study: characterization of as-deposited SiC coatings; thermodynamics and kinetics of chemical reactions between SiC and fission products; irradiation behavior of SiC in the absence of fission products; and combined effects of irradiation and fission products. This paper reports the behavior of SiC deposited on inert microspheres and irradiated to fast-neutron fluences typical of HTGR fuel at end-of-life.

Lauf, R.J.

1983-01-01

274

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

275

Microbeam analysis of irradiated nuclear fuel  

NASA Astrophysics Data System (ADS)

Microbeam analysis is widely used in the nuclear power industry. It is used to characterise the as-fabricated fuel, for routine post-irradiated examination and for research into the mechanisms of phenomena that limit the energy production of the fuel. The techniques most commonly used are wavelength-dispersive electron probe microanalysis, scanning electron microscopy and secondary ion mass spectrometry. Other microbeam analysis techniques that have been successfully applied to irradiated nuclear fuel are transmission and replica electron microscopy, X-ray fluorescence and micro X.-ray diffraction. Specific examples illustrating the past and present use of microbeam analysis in nuclear research establishments are presented with emphasis on the unique results they provide. As an aid to understanding, some basic facts about nuclear fuel rods and their irradiation are first given. This is followed by a description of features that set apart the microbeam analysis of high radioactive materials from standard practice.

Walker, C. T.; Brémier, S.; Pöml, P.; Papaioannou, D.; Bottomley, P. W. D.

2012-03-01

276

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

277

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.

278

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

279

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

280

Measurement and Analysis of Diffuse Solar Irradiance.  

NASA Astrophysics Data System (ADS)

Measurements of the diffuse irradiance on a horizontal surface using a continuous tracking occulting disc and a pyranometer have been examined for cloudless days. The part of the diffuse component that is blocked by the occulting disc (circumsolar component) is analyzed with respect to the aerosol optical depth at a wavelength of 500 nanometers, solar zenith angle, and precipitable water. The magnitude of the circumsolar component is determined from the direct normal irradiance measured with a pyrheliometer, aerosol optical depth and precipitable water measured with a Volz sun photometer, and direct normal irradiance calculated from a direct-beam model (Bird, 1982). The pyrheliometer measures the direct beam as well as the circumsolar component. The model was used to estimate only the direct beam over the same spectral interval as measured by the pyrheliometer. The computed component is subtracted from the measured direct normal irradiance and multiplied by the cosine of the solar zenith angle. The difference is an approximate value of the circumsolar irradiance on a horizontal surface. It is found that the circumsolar irradiance is a maximum for a small solar zenith angles, low aerosol optical depths, and small amounts of precipitable water. The total diffuse component is a minimum for these conditions. The magnitude of the portion blocked is within 10% of the measured diffuse. In general, for a given solar zenith angle and low precipitable water, the correction to the measured diffuse decreases with an increase in aerosol optical depth; the diffuse component for these conditions increases while the circumsolar component decreases. The largest change occurred for an increase in aerosol optical depth from .153 to .337, a solar zenith angle of 35 degrees, and 0.5 precipitable centimeters of water. The circumsolar component decreased by 17% and the measured diffuse increased by 50%. This corresponded to a 33% reduction in the multiplying factor applied to the measured diffuse to obtain agreement with the measured diffuse plus the circumsolar component.

Baker, Clifford Bruce

281

Heavy Ion Irradiation Effects in Zirconium Nitride  

SciTech Connect

Polycrystalline zirconium nitride (ZrN) samples were irradiated with He{sup +}, Kr{sup ++}, and Xe{sup ++} ions to high (>1.10{sup 16} ions/cm{sup 2}) fluences at {approx}100 K. Following ion irradiation, transmission electron microscopy (TEM) and grazing incidence X-ray diffraction (GIXRD) were used to analyze the microstructure and crystal structure of the post-irradiated material. For ion doses equivalent to approximately 200 displacements per atom (dpa), ZrN was found to resist any amorphization transformation, based on TEM observations. At very high displacement damage doses, GIXRD measurements revealed tetragonal splitting of some of the diffraction maxima (maxima which are associated with cubic ZrN prior to irradiation). In addition to TEM and GIXRD, mechanical property changes were characterized using nano-indentation. Nano-indentation revealed no change in elastic modulus of ZrN with increasing ion dose, while the hardness of the irradiated ZrN was found to increase significantly with ion dose. Finally, He{sup +} ion implanted ZrN samples were annealed to examine He gas retention properties of ZrN as a function of annealing temperature. He gas release was measured using a residual gas analysis (RGA) spectrometer. RGA measurements were performed on He-implanted ZrN samples and on ZrN samples that had also been irradiated with Xe{sup ++} ions, in order to introduce high levels of displacive radiation damage into the matrix. He evolution studies revealed that ZrN samples with high levels of displacement damage due to Xe implantation, show a lower temperature threshold for He release than do pristine ZrN samples. (authors)

Egeland, G.W.; Bond, G.M. [New Mexico Institute of Mining and Technology, Socorro, NM 87801 (United States); Valdez, J.A.; Swadener, J.G.; McClellan, K.J.; Maloy, S.A.; Sickafus, K.E. [Los Alamos National Lab (United States); Oliver, B. [Pacific Northwest National Lab (United States)

2004-07-01

282

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

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

283

Electron irradiation of modern solar cells  

NASA Technical Reports Server (NTRS)

A number of modern solar cell types representing 1976 technology (as well as some older types) were irradiated with 1 MeV electrons (and a limited number with 2 MeV electrons and 10 MeV protons). After irradiation, the cells were annealed, with I-V curves measured under AMO at 30 C. The purpose was to provide data to be incorporated in the revision of the solar cell radiation handbook. Cell resistivities ranged from 2 to 20 ohm-cm, and cell thickness from 0.05 to 0.46 mm. Cell types examined were conventional, shallow junction, back surface field (BSF), textured, and textured with BSF.

Anspaugh, B. E.; Miyahira, T. F.

1977-01-01

284

Processing of diamond by laser beam irradiation  

NASA Astrophysics Data System (ADS)

YAG and ArF excimer laser beams, of which wavelengths are 1.06 micrometers and 193 nm respectively, have been applied to processing of a variety of diamonds. Cutting and smoothing of natural, CVD and sintered diamonds have been performed. CVD diamond films were prepared by arc discharge plasma jet CVD and microwave plasma CVD, and sintered diamonds contain metallic or ceramic binder have been used. Fundamental removal processes of diamond with YAG and ArF excimer laser have been investigated using natural single crystal and CVD diamonds in various atmospheres changing laser irradiation conditions such as average power, energy density and pulse repetition rates. Cutting of natural and CVD diamonds with YAG laser proceeds at higher peal power that occurs at lower pulse repetition rates. Smooth surfaces are obtained by excimer laser irradiation at the incident angle of 80 percent. In the cases of the processing with YAG laser, the effect of local heating by laser beam irradiation mainly assists the diamond processing, and diamond appears to be removed after graphitization and oxidization following vaporization in the atmosphere contains oxygen. The temperature measurement was carried out at backside of irradiation surface, and increase of temperature when YAG laser beam was irradiated was larger than that when excimer laser was irradiated. On the contrary, the detection of C, C2, C+, O2 and CO from the emission at the irradiation area with ArF excimer laser beam suggest that processing partly proceeds by the separation of carbon atoms from the surface of diamond after braking bonds between carbon atoms caused by laser beam. Cutting of sintered diamond with metallic binder was difficult because metallic binder remains in the groove while ceramic binder was easily removed. Processing technique using laser beams has been applied to surface planing, chip preparation and edge formation of CVD diamond and curved surface formation on sintered diamond. Surface planing was carried out by directing the YAG laser beam parallel to the surface of diamond films and diamond chips were prepared by the combination of cutting and surface planing techniques. A sharp edge was formed between the surfaces which cut by laser beam and mechanically polished. Round nose was formed by gradually rotating the sintered diamond following YAG laser beam irradiation.

Yoshikawa, Masanori; Hirata, Atsushi

1998-10-01

285

Agglomeration defects on irradiated carbon nanotubes  

SciTech Connect

Aligned carbon nanotubes (CNT) were irradiated in the longitudinal and perpendicular directions, with low energy carbon and helium ions in order to observe the formation of defects in the atomic structure. Analysis through Raman spectroscopy and scanning electron microscopy indicated bundle rupture and ion track formation on nanotube bundles. Aligned CNT presented a kind of defect comprising ravine formation and tube agglomeration on top of the substrate. The latter structure is possibly caused by static charge accumulation induced by the incoming ions. Fluence plays a role on the short range order. Higher fluence irradiation transforms CNT into amorphous carbon nanowires.

Steini Moura, Cassio [Faculty of Physics, Pontificia Universidade Catolica do Rio Grande do Sul, 90619-900, Porto Alegre, RS (Brazil); Balzaretti, Naira Maria; Amaral, Livio [Institute of Physics, Universidade Federal do Rio Grande do Sul, C.P.: 15051, 91501-070, Porto Alegre, RS (Brazil); Gribel Lacerda, Rodrigo; Pimenta, Marcos A. [Universidade Federal de Minas Gerais, C.P.: 702, 31270-901, Belo Horizonte, MG (Brazil)

2012-03-15

286

Strengthening the security of gamma irradiators  

NASA Astrophysics Data System (ADS)

Recently, the United States has seen an increasing emphasis on security as related to potential terrorist threats. One aspect that has received attention is the radiological dispersal device ("dirty bomb"), in particular the possibility of obtaining radioactive material for producing such devices. As a result, the security of US gamma irradiators has been the focus of industry efforts to reinforce protection of high-activity sources. This paper presents approaches that may be used to improve security at gamma irradiation facilities, including increased vigilance, education and awareness, and physical changes to the facility. As each method has been or is being implemented, employee involvement is a critical factor to success.

Young, J.; Smith, M.

2004-09-01

287

Evaluation of 2-dodecylcyclobutanone as an irradiation dose indicator in fresh irradiated ground beef.  

PubMed

Alkylcyclobutanones (2-ACBs) are radiolytic products formed when fatty acids are irradiated. These cyclobutanones are unique irradiation byproducts and therefore may serve as indicators of irradiation exposure. As only limited information exists about 2-ACB formation in retail meat products, reliable methods that can quantify 2-ACBs and thus estimate irradiation dose in commercial meat products are desired. The cyclobutanone studied in this experiment was 2-dodecylcyclobutanone (2-DCB), which is formed from palmitic acid. The formation of 2-DCB was evaluated in fresh irradiated ground beef patties at two fat levels. Patties containing 15% and 25% fat were irradiated by electron beam at 1.0, 2.0, 3.0, and 4.5 kGy. Commercially available 1-lb irradiated ground beef chubs with different fat levels were analyzed in order to estimate dose absorbed by these samples. The 2-DCB was extracted using supercritical fluid extraction (SFE) and analyzed by gas chromatography-mass spectroscopy (GC-MS) and was detected in all the irradiated samples. The concentration of 2-DCB increased linearly with dose with R2 = 0.9646 for 25% fat samples and R2 = 0.9444 for 15% fat samples. Further, there was no significant difference in 2-DCB concentrations between the two fat levels. The estimated doses applied to the commercial samples ranged between 1.38 and 1.55 kGy, values consistent with doses normally used in the industry (1.0-2.0 kGy). Our results show that 2-DCB can be used to monitor fresh irradiated beef and approximate the absorbed dose. PMID:15769109

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

2005-03-23

288

NBS (National Bureau of Standards) Measurement Services: Spectral Irradiance Calibrations.  

National Technical Information Service (NTIS)

The report describes the measurement methods and instrumentation used in realization and transfer of the NBS scale of spectral irradiance. The basic measurement equation for the irradiance realization is derived. The spectral responsivity function, linear...

J. H. Walker R. D. Saunders J. K. Jackson D. A. McSparron

1987-01-01

289

Heavy ion irradiation of U Mo/Al dispersion fuel  

NASA Astrophysics Data System (ADS)

The usage of high-density U-Mo/Al dispersion fuel for high burn up in research and test reactors seems to be limited by the unfavourable interdiffusion layer between the fuel and the Al-matrix, which develops during irradiation. This interdiffusion layer was observed up to now only after costly and time consuming in-pile irradiation and could not be created in out-of-pile experiments. This paper presents a new approach of creating such an interdiffusion layer out-of-pile by irradiation with heavy ions. An appropriate choice of heavy-ion irradiation simulates irradiation damage and deposition of fission fragments as it happens during in-pile irradiation and induces a diffusion process between the fuel and the Al matrix. An irradiation experiment and post-irradiation examinations are presented.

Wieschalla, N.; Bergmaier, A.; Böni, P.; Böning, K.; Dollinger, G.; Großmann, R.; Petry, W.; Röhrmoser, A.; Schneider, J.

2006-10-01

290

Irradiation of White Potatoes, for Sprout Inhibition, with Cobalt-60.  

National Technical Information Service (NTIS)

Irradiation at the described level will increase the utilization of stored tubers. The treatment will, in effect, reduce losses that occur during storage through inhibition of sprouting. Treatment with minimum sprout inhibition levels of gamma irradiation...

1964-01-01

291

Prevention of browning of depolymerized chitosan obtained by gamma irradiation.  

PubMed

In this paper, effect of oxygen and pH on the browning of chitosan exposed to gamma radiation was investigated. It was found that oxygen and pH value could play important roles in the inhibiting browning of irradiated chitosan. When the pH value of chitosan solution was below 3.0, sufficient oxygen could inhibit browning of irradiated chitosan in aqueous solution. As a result of irradiation of chitosan solution (pH<3) with sufficient oxygen, the irradiated chitosan solutions obtained were colorless and pellucid. FT-IR, (13)C NMR, and UV-vis spectra confirmed that the irradiation in the presence of oxygen cannot result in chemical modification of irradiated chitosan. An effective technology was developed for the inhibition of browning of irradiated chitosan during depolymerization of chitosan by gamma irradiation. PMID:24299848

Yue, Wu

2014-01-30

292

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

293

TEM Examination of Advanced Alloys Irradiated in ATR.  

National Technical Information Service (NTIS)

Successful development of materials is critical to the deployment of advanced nuclear power systems. Irradiation studies of candidate materials play a vital role for better understanding materials performance under various irradiation environments of adva...

B. A. Hilton J. Gan

2007-01-01

294

Irradiation performances of the Superphenix type absorber element.  

National Technical Information Service (NTIS)

Several aspects of irradiation behaviour of the SUPERPHENIX type absorber element are presented in this paper. A large programme of irradiation tests was performed in PHENIX to assess and to improve the absorber pin design whose main characteristics for t...

B. Kryger D. Gosset J. M. Escleine

1995-01-01

295

Irradiation Creep Induced Anisotropy in a/2 Dislocation Populations.  

National Technical Information Service (NTIS)

The contribution of anisotropy in Burgers vector distribution to irradiation creep behavior has been largely ignored in irradiation creep models. However, findings on Frank loops suggest that it may be very important. Procedures are defined to identify th...

D. S. Gelles

1984-01-01

296

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

PubMed Central

To evaluate the effects of different gamma irradiation doses on PEGd,lPLA and PEG-PLGA multiblock copolymers. The behaviour of the multiblock copolymers to irradiation was compared to that of PLA, PLGA polymers. PEGd,lPLA, PEG-PLGA, PLA and PLGA polymers were irradiated by using a 60Co irradiation source at 5, 15, 25 and 50 kGy total dose. Characterization was performed on all samples before and after irradiation, by nuclear magnetic resonance (NMR), infrared absorption spectrophotometry (FTIR) and gel permeation chromatography (GPC). The effect of gamma irradiation on polymer stability was also evaluated. Results of NMR and FTIR suggest an increase in -OH and -COOH groups, attributed to scission reactions induced by irradiation treatment. Data of GPC analysis showed that the weight average molecular weight (Mw) of polymer samples decreased with increasing irradiation dose. The extent of Mw degradation expressed as percentage of Mw reduction was more prominent for polymers with high molecular weight as PEGd,lPLA and PLA. The dominant effect of gamma-irradiation on both polymer samples was chain scission. The multiblock copolymer PEGd,lPLA presented higher sensitivity to irradiation treatment with respect to PLA, likely due to the presence of PEG in the matrix. The effect of gamma irradiation continues over a much longer period of time after gamma irradiation has been performed. It is suggested that the material reacts with oxygen to form peroxyl free radicals, which may further undergo degradation reactions during storage after irradiation.

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

2008-01-01

297

OMEGA: a 24 beam uv irradiation facility  

SciTech Connect

We report the recent completion of the uv upconversion (351 nm) of all 24 beams of the OMEGA laser which provides a unique short wavelength symmetrical irradiation facility for direct drive laser fusion experiments. Details of the characterization of illumination uniformity and initial implosion experiments will be described.

Richardson, M.C.; Beich, W.; Delettrez, J.; Dunn, M.; Folnsbee, L.; Hutchison, R.J.; Jacobs, S.A.; Keck, R.; Kessler, T.; Lampeter, W.

1985-01-01

298

Metallographic examination in irradiated materials examination facility.  

National Technical Information Service (NTIS)

It is very important to have equipment of metallographic examination in hot- cell to observe the micro-structure of nuclear fuels and materials irradiated at nuclear power and/or research reactor. Those equipment should be operated by master-slave manipul...

Y. S. Choo K. S. Lee D. G. Park S. B. Ahn B. O. Yoo

1998-01-01

299

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

300

Post irradiation examination of thermal reactor fuels  

Microsoft Academic Search

The post irradiation examination (PIE) facility at the Bhabha Atomic Research Centre (BARC) has been in operation for more than three decades. Over these years this facility has been utilized for examination of experimental fuel pins and fuels from commercial power reactors operating in India. In a program to assess the performance of (U,Pu)O2 MOX fuel prior to its introduction

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

2008-01-01

301

Irradiation Effects on Reactor Structural Materials.  

National Technical Information Service (NTIS)

This report, covering research for the period 1 August 1964 - 31 October 1964, includes the following: (1) simultaneous irradiation of six heavy plate structural steels at 700F and of A350-LF3 and A212-B steels at 500F, (2) effect of nuclear environment o...

L. E. Steele J. R. Hawthorne C. Z. Serpan

1964-01-01

302

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

303

Irradiation of Lithium Aluminate and Tritium Extraction.  

National Technical Information Service (NTIS)

After preselection of the preparation procedures, following short irradiations, gamma LiAlO sub 2 samples submitted to 2.10 exp 19 fast neutrons cm exp -2 and 1.5 10 exp 20 thermal neutrons cm exp -2 fluences experienced no apparent damage. Post-irradiati...

E. Roth F. Botter J. J. Abassin M. Briec P. Chenebault

1984-01-01

304

Susceptibility of irradiated steels to hydrogen embrittlement  

NASA Technical Reports Server (NTRS)

Investigation determined whether irradiated pressure-vessel steels 4340 and 212-B are susceptible to hydrogen embrittlement and to catastrophic failure. Hydrogen-charging conditions which completely embrittled 4340 steel had negligible effect on 212-B steel in tensile and delayed-failure tests.

Rossin, A. D.

1968-01-01

305

Charge Deposition Profiles near Irradiated Material Interfaces  

Microsoft Academic Search

Charge deposition profiles in thin planar layers of aluminum, tin and tantalum next to various combinations of thick layers of aluminum, copper, tin and lead have been measured under cobalt 60 irradiation. The gamma ray beam is collimated and its energy spectrum is measured. The gamma intensity is accurately determined so that the absolute charge deposition can be related to

A. R. Frederickson

1976-01-01

306

Theoretical assessment of irradiation swelling in beryllium  

NASA Astrophysics Data System (ADS)

Current models of irradiation swelling in beryllium are based on the assumption that the swelling arises from bubble growth rather than void growth. However, the factors governing cavity formation in beryllium are more complex than those in cubic metals which are based on elastic interaction difference (EID) between vacancies and self-interstitial atoms. Beryllium belongs to the set of hexagonal close-packed metals where diffusion has been shown to be anisotropic. Diffusional anisotropy difference (DAD) between point defects changes the cavity bias for their absorption and leads to dependence of the dislocation bias on the distribution of dislocations over crystallographic directions. This results in new critical quantities for the bubble—void transition that controls transition from low-dose to high-dose irradiation effects. In the present paper, we show how the critical parameters controlling irradiation swelling in beryllium depend on the distribution of dislocations over crystallographic directions taking into account an anomalously high anisotropy of self-diffusion in beryllium. The latter is shown to be in agreement with experimentally observed resistance of beryllium to void swelling at early stages of irradiation when a-type dislocations prevail over c-type dislocations. However, a mechanism of radiation-induced production of c-type dislocation loops is proposed that can lead to a subsequent transition of bubbles to voids.

Dubinko, V. I.; Barabash, V. R.

1996-10-01

307

Durability of Polymeric Coatings: UV-Irradiation  

Microsoft Academic Search

Durability of polymeric coatings is investigated by using positron annihilation spectrscopy and gloss measurements in a variety of commercial coatings and model polyurethane under UV irradiation of both accelerated and natural weathering conditions. Significant variations of sub-nanometer defect parameters determined from PAS results are observed as a function of depth, of exposure time, and of weathering conditions. The loss of

Ying Li; Renwu Zhang; Chia-Ming Huang; Junjie Zhang; Peter Mallon; R. Suzuki; Y. Y. Huang; T. C. Sandreczki; Q. Peng; J. R. Richardson; T. Ohdaira; Y. C. Jean

2001-01-01

308

Raman spectroscopy of C-irradiated graphite.  

National Technical Information Service (NTIS)

Highly oriented pyrolytic graphite samples were irradiated with C(sup +) ions at 35 keV in a direction normal to the basal plane and subsequently annealed up to 1373 K. Substantial surface topography changes were observed at fluences of 5 (times) 10(sup 1...

D. M. Hembree D. F. Pedraza G. R. Romanoski S. P. Withrow B. K. Annis

1994-01-01

309

Neck irradiation, carotid injury and its consequences.  

PubMed

Carotid stenosis is a major sequela of head and neck irradiation that has not received the attention it deserves. Its impact on the quality of life of patients can be substantial. This review discusses the incidence, pathogenesis and consequences of radiation-induced carotid stenosis following head and neck irradiation. This review is based on literature search (Medline and Pub Med) and cross-referencing. The incidence of significant carotid stenosis following head and neck irradiation range from 30% to 50%. Patients with carotid stenosis are at increased risk for stroke. Factors such as hypertension, diabetes, smoking and obesity increase the risk. Increased attention to the clinical signs of carotid stenosis and evaluation of these patients with appropriate imaging studies, together with strict implementation of management of hypertension and diabetes and, counseling on obesity and smoking have the potential to reduce the incidence of this sequela of head and neck irradiation. Those patients with severe carotid stenosis can be managed with endarterectomy or carotid artery stenting. PMID:15380164

Abayomi, Olubunmi K

2004-10-01

310

Variability of UV Irradiance in Europe  

Microsoft Academic Search

The diurnal and annual variability of solar UV radiation in Europe is described for different latitudes, seasons and different biologic weighting functions. For the description of this variability under cloudless skies the widely used one- dimensional version of the radiative transfer model UVSPEC is used. We reconfirm that the major factor influencing the diurnal and annual variability of UV irradiance

Gunther Seckmeyer; Darius Pissulla; Merle Glandorf; Diamantino Henriques; Bjorn Johnsen; Ann Webb; Anna-Maria Siani; Alkis Bais; Berit Kjeldstad; Colette Brogniez; Jacqueline Lenoble; Brian Gardiner; Peter Kirsch; Tapani Koskela; Jussi Kaurola; Beate Uhlmann; Harry Slaper; Peter den Outer; Michal Janouch; Peter Werle; Julian Grobner; Bernhard Mayer; Alain de la Casiniere; Stana Simic; Fernanda Carvalho

2008-01-01

311

Association between primary hyperparathyroidism and previous irradiation  

SciTech Connect

The association between primary hyperparathyroidism and previous irradiation was investigated in two study groups. Among 36 patients with hyperparathyroidism, 4 (11%) knew of having received radiation therapy. In the second group of 323 patients with a history of radiation exposure and nodular thyroid disease, 4 (1%), thus far, were found to have hyperparathyroidism.

Tamura, K.; Shimaoka, K.; Spaulding, S.; Shedd, D.

1982-04-01

312

Theoretical assessment of irradiation swelling in beryllium  

Microsoft Academic Search

Current models of irradiation swelling in beryllium are based on the assumption that the swelling arises from bubble growth rather than void growth. However, the factors governing cavity formation in beryllium are more complex than those in cubic metals which are based on elastic interaction difference (EID) between vacancies and self-interstitial atoms. Beryllium belongs to the set of hexagonal close-packed

V. I. Dubinko; V. R. Barabash

1996-01-01

313

Effects of hadron irradiation on scintillating fibers  

SciTech Connect

Trackers based on scintillating-fiber technology are being considered by the Solenoidal Detector Collaboration at SSC and the D[phi] collaboration at Fermilab. An important issue is the effect of the radiation existing in the detector cores on fiber properties. Most studies of radiation damage in scintillators have irradiated small bulk samples rather than fibers, and have used X-rays, [sup 60]Co gammas, or electron beams, often at accelerated rates. The authors have irradiated some 600 fibers in the Fermilab Tevatron C[phi] area, thereby obtaining a hadronic irradiation at realistic rates. Four-meter-long samples of ten Bicron polystyrene-based fiber types, maintained in air, dry nitrogen, argon, and vacuum atmospheres within stainless-steel tubes, were irradiated for seven weeks at various distances from the accelerator beam pipes. Maximum doses, measured by thermoluminescence detectors, were about 80 Krad. Fiber properties, particularly light yield and attenuation length, have been measured over a one-year period. A description of the work together with the results is presented. At the doses achieved, corresponding to a few years of actual fiber-tracking detector operation, little degradation is observed. In addition, recovery after several days' exposure to air has been noted. Properties of unirradiated samples kept in darkness show no changes after one year.

Atac, M. (Univ. of California, Los Angeles, CA (United States) Fermi National Accelerator Lab., Batavia, IL (United States)); Buchanan, C.; Chrisman, D.; Cline, D.; Kolonko, J.; Kubic, J.; Park, J. (Univ. of California, Los Angeles, CA (United States)); Baumbaugh, A.; Binkley, M.; Bross, A.D.; Finley, D.; Elias, J.; Foster, G.W.; Kephart, R.; Kephart, R.; Kim, C.; Park, H.; Pla-Dalmau, A.; Rivetta, C.; Tkaczyk, S.; Wagner, R. (Fermi National Accelerator Lab., Batavia, IL (United States)); Chung, M.; Goldberg, H.; Jeskik, R.; Margulies, S.; Mendez, H.; Solomon, J.; Vaca, F. (Univ. of Illinois, Chicago, IL (United States)); Kelley, C. (Massachusetts College of Pharmacy and Allied Health Sciences, Boston, MA (United States)); Baumbaugh, B.; Bishop, J.; Biswas, N.; Cason, N.; Jacques, J.; Kehoe, R.; Kelly, M.; Kenney, V.; LoSecco, J.; Ruchti, R.; Shephard, W.; Warchol, J.; Wayne, M.; Marchant, J.; Mountain, R.J. (Univ. of Notre Dame, IN (United States)); Davis, D.; Vandergriff, D. (O

1993-08-01

314

IRRADIATION INDUCED EFFECTS IN MAGNESIUM OXIDE CATALYSTS  

Microsoft Academic Search

An attempt was made to find a model system in which to study irradiation ; effects on heterogeneous catalysts. Preirradiation with gamma rays from Co\\/sup ; 60\\/ enhanced the rate of hydrogen conversion over MgO catalysts, especially when ; the oxide was pretreated with oxygen at elevated temperature. No correlation ; could be found between the catalytic activity and the

J. Hoigne; D. Ballantine

1961-01-01

315

Tolerance of normal tissue to therapeutic irradiation  

Microsoft Academic Search

The importance of knowledge on tolerance of normal tissue organs to irradiation by radiation oncologists cannot be overemphasized. Unfortunately, current knowledge is less than adequate. With the increasing use of 3-D treatment planning and dose delivery, this issue, particularly volumetric information, will become even more critical. As a part of the NCI contract N01 CM-47316, a task force, chaired by

B. Emami; J. Lyman; A. Brown; L. Coia; M. Goitein; J. E. Munzenrider; B. Shank; L. J. Solin; M. Wesson

1991-01-01

316

Responses of hyperthermophilic crenarchaea to UV irradiation  

Microsoft Academic Search

BACKGROUND: DNA damage leads to cellular responses that include the increased expression of DNA repair genes, repression of DNA replication and alterations in cellular metabolism. Archaeal information processing pathways resemble those in eukaryotes, but archaeal damage response pathways remain poorly understood. RESULTS: We analyzed the transcriptional response to UV irradiation in two related crenarchaea, Sulfolobus solfataricus and Sulfolobus acidocaldarius. Sulfolobus

Dorothee Götz; Sonia Paytubi; Stacey Munro; Magnus Lundgren; Rolf Bernander; Malcolm F White

2007-01-01

317

Dynamics of a Laser-Irradiated Adatom.  

National Technical Information Service (NTIS)

The dynamics of an adsorbed atom irradiated by an IR laser in resonance with a single pair of states of the vibrational adbond is studied. Using a non-perturbative treatment for the laser adbond interaction, a master equation is derived, which governs the...

S. van Smaalen A. Peremans H. F. Arnoldus T. F. George

1986-01-01

318

Determination of Nitride Nitrogen in Irradiated Materials.  

National Technical Information Service (NTIS)

A method for determining nitride nitrogen was adapted for analyses of irradiated samples in a hot cell. Sections of stainless steel cladding material or fuel are dissolved remotely using various combinations of H sub 2 SO sub 4 , HCl, and HF. The nitrogen...

M. A. Maez

1979-01-01

319

Management of mucositis in oral irradiation  

Microsoft Academic Search

Mucositis significantly affects quality of life and tolerance of treatment in oral irradiation. Effective management of this complication is therefore very important. However, there is a scarcity of up-to-date oral care protocols, with most centres using ritualized regimens. The literature on oral rinses in radiation mucositis is at best inconclusive and at worst confusing. In this study, patients undergoing radical

T. Feber

1996-01-01

320

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

321

Mantle irradiation of the major salivary glands  

SciTech Connect

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

Kaplan, P.

1985-11-01

322

Sterilisation of skin allograft with gamma irradiation.  

PubMed

The primary surgical requirement of skin allografts within the UK is for cryopreserved viable allografts as these engraft to the wound bed and gain a vascular supply, thus providing true wound closure and a superior clinical performance. Consequently the only disinfection treatment the skin receives is exposure to an antibiotic cocktail. However, antibiotic treatment does not reliably decontaminate skin allografts and 22% of cryopreserved skin fails microbial acceptance criteria and cannot be used clinically. We describe here a study which was carried out to determine a means of saving and using the microbiologically failed skin. Four different treatment regimens were investigated; treatment with 20%, 50% and 85% glycerol followed by 25 kGy irradiation at -80 degrees C, and treatment with 85% glycerol at ambient (30-40 degrees C) temperature and irradiation. Following treatment, the grafts were evaluated for their histological structure, in vitro cytotoxicity and handling properties. The radioprotective effects of the different glycerol concentrations and temperatures on microorganisms were also determined. The data indicate that 25 kGy irradiation of deep-frozen skin in 20% glycerol sterilised the tissue without any histological, cytotoxicological or physical alterations compared to normal cryopreserved skin. In contrast, irradiation of all other glycerol concentrations elicited some cytotoxicity and/or histological effect. These non-viable grafts can be made available for surgical use when cryopreserved viable grafts are not available or required. PMID:18226461

Rooney, P; Eagle, M; Hogg, P; Lomas, R; Kearney, J

2008-08-01

323

Irradiation Effects on Reactor Structural Materials.  

National Technical Information Service (NTIS)

The report, covering research for the period 1 May - 31 July 1969, includes the following: (1) irradiation response of A543 steel to different thermal/fast neutron fluxes, (2) mechanical property and neutron spectrum analyses of the Big Rock Point Reactor...

L. E. Steele C. Z. Serpan R. A. Gray H. E. Watson F. A. Smidt

1969-01-01

324

Food irradiation newsletter. V.18, no.1.  

National Technical Information Service (NTIS)

This newsletter contains a report on the 10th Annual Meeting of the International Consultative Group on Food Irradiations, summaries of the Second Research Co-ordination Meetings(RCMs) and Final RCM of the Asian Regional Co-operative Project on Food Irrad...

1994-01-01

325

Reconstructing Tumour Defects: Lyophilised, Irradiated Bone Allografts  

Microsoft Academic Search

Tumour excision leaves behind large defects. Allografts provide an excellent alternative to autografts without donor site morbidity and are especially useful in large defects or in children where the quantity of available autograft is limited. In this paper we discuss our experience with indigenously procured and processed lyophilised, irradiated bone allografts. Bone allografts were used in 41 patients. They were

A. Lobo Gajiwala; M. Agarwal; A. Puri; C. D'Lima; A. Duggal

2003-01-01

326

Compositional profiles of ?-irradiated cashew nuts  

Microsoft Academic Search

Cashew nuts, an important export item from India, contribute to about 7% of the national exchequer. Insect infestation of the cashew nut, leading to economic losses is a frequently encountered problem. The present work aims to combat this problem by using low dose ?-irradiation and evaluating the effect of such treatment on the physico-chemical properties of cashew nuts. Cashew nuts,

Paramita Bhattacharjee; Rekha S Singhal; Achyut S Gholap; Prasad S Variyar; Dilip R Bongirwar

2003-01-01

327

Hard ormosils prepared with ultrasonic irradiation  

Microsoft Academic Search

Organically modified silicates (ormosils) of high hardness were prepared by the reaction of TEOS (tetraethoxysilane) and PDMS (polydimethylsiloxane) aided by ultrasonic irradiation, which was chosen as the method for concentration of the solutions. The mechanisms leading to the hard ormosil formation were examined by liquid state 29Si NMR spectroscopy. PDMS chains were found to be broken into shorter chains and\\/or

Takashi Iwamoto; John D. Mackenzie

1995-01-01

328

Performance of irradiated CMS forward pixel detector  

Microsoft Academic Search

The performance of a module of the CMS forward pixel detector irradiated up to a maximum dose of 45 Mrad was investigated at a beam test at Fermilab. The conclusion is that the CMS forward pixel detector can easily tolerate this radiation dose without any impact on the CMS physics performance.

S. Taroni

2010-01-01

329

THE IRRADIATION OF ION EXCHANGERS IN JEEP  

Microsoft Academic Search

Several organic and inorganic ion exchanger materials were irradiated in ; JEEP. Radiation effects are dcscribed and dependence on dose rate and quality of ; the radiation is discussed. By comparing the action of different kinds of ; ionizing radiation, possible reaction mechanisms are discussed. (authl;

Nater

1959-01-01

330

EFFECT OF GAMMA IRRADIATION UPON CELLULOSE  

Microsoft Academic Search

The purified cotton linter and purified wood pulp were irradiated by ; gamma radiation at various doses, and the number-average degree of polymerization ; (DP) of each sample was determined according to the method worked out by Immergut ; et al. by the measurements of intrinsic viscosity. The log-log plots of the ; difference between the reciprocal of DP of

M. Horio; R. Imamura; H. Mizukami

1963-01-01

331

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

332

Amphytrion: Example of a high capacity irradiator  

NASA Astrophysics Data System (ADS)

SGN recently built a pallet irradiator for the AMPHYTRION Company which incorporates new technological features. After a short review of the design criteria, the major mechanical equipment is described (source-holder, conveyor, automatic warehouse system), together with the ventilation/air conditioning system and the control/management architecture. Information is given on the new technical aspects and the performance of the facility.

Keraron(SGN-France), Y.; Santos(Amphytrion-France), P. L.

333

Irradiation corporelle totale : présent et avenir  

Microsoft Academic Search

Total body irradiation (TBI) has an established role as preparative regimen for bone-marrow transplantation in the treatment of hematological malignancies. Many randomized trials demonstrated that the clinical outcomes obtained from the association of TBI and cyclophosphamide are equivalent, or, sometimes, better than those based on chemotherapeutic agents. Despite the therapeutic progress of the last years, and the consequent improvement in

T. Zilli; R. Miralbell; M. Ozsahin

2009-01-01

334

An efficient representation for irradiance environment maps  

Microsoft Academic Search

We consider the rendering of diffuse objects under distant illumination, as specified by an environment map. Using an analytic expression for the irradiance in terms of spherical harmonic coefficients of the lighting, we show that one needs to compute and use only 9 coefficients, corresponding to the lowest-frequency modes of the illumination, in order to achieve average errors of only

Ravi Ramamoorthi; Pat Hanrahan

2001-01-01

335

Aspheric surface testing by irradiance transport equation  

NASA Astrophysics Data System (ADS)

In this paper a method for aspheric surface testing is presented. The method is based on solving the Irradiance Transport Equation (ITE).The accuracy of ITE normally depends on the amount of the pick to valley of the phase distribution. This subject is investigated by a simulation procedure.

Shomali, Ramin; Darudi, Ahmad; Nasiri, Sadollah; Asgharsharghi Bonab, Armir

2010-05-01

336

Antitumor Immunity Induced after ? Irradiation123  

PubMed Central

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 (213Bi) 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 213Bi-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.

Gorin, Jean-Baptiste; Menager, Jeremie; Gouard, Sebastien; Maurel, Catherine; Guilloux, Yannick; Faivre-Chauvet, Alain; Morgenstern, Alfred; Bruchertseifer, Frank; Cherel, Michel; Davodeau, Francois; Gaschet, Joelle

2014-01-01

337

Irradiation-Induced Swelling in Commercial Alloys.  

National Technical Information Service (NTIS)

Examination of a wide range of commercial alloys indicates that a minimum in swelling occurs at 40 to 50% nickel. Swelling in these alloys was measured after irradiation to peak fluences of 14.7 x 10 exp 22 n/cm exp 22 (E > 0.1 MeV) at temperatures rangin...

J. F. Bates R. W. Powell

1980-01-01

338

ESR analysis of irradiated frogs' legs and fishes.  

PubMed

Electron spin resonance (ESR) spectral analysis of different parts (bones, scales, jaw, etc.) from ionized (irradiated) frozen frogs' legs and fishes (brown trout and sardine) were recorded. There is always present, after treatment, a signal due to the irradiation. ESR and ENDOR experiments lead us to assign it to h1 centers from hydroxyapatite, as in the case of other irradiated meat bones. The use of ESR to prove whether one of these foods has been irradiated or not is discussed. PMID:2559057

Raffi, J; Evans, J C; Agnel, J P; Rowlands, C C; Lesgards, G

1989-01-01

339

Effects of residual stress on irradiation hardening in stainless steels  

Microsoft Academic Search

Effects of residual stress on irradiation hardening were studied in advance for predicting irradiation assisted stress corrosion cracking. The specimens of SUS316 and SUS316L with several % plastic strains, which correspond to weld residual stress, were prepared by bending and keeping deformation under irradiation. Ion irradiations of 12MeV Ni3+ were performed at 330, 400 and 550oC to 45dpa. No bended

N. Okubo; Y. Miwa; K. Kondo; Y. Kaji

2009-01-01

340

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 800–1000Gy resulted in small empty seeds in ‘Fujihikari TR’, whereas 400–1000Gy doses gave

Keita Sugiyama; Masami Morishita

2000-01-01

341

Comparisons of modeled and measured spectral solar irradiance data  

SciTech Connect

This report contains comparisons of modeled and measured spectral solar irradiance data made at the Solar Energy research Institute (SERI). The modeled data were generated using a simple, spectral solar irradiance model developed at SERI; measured data were obtained with LI-COR model LI-1800 portable spectroradiometers specially modified at SERI. This work is part of a continuing endeavor to verify spectral irradiance models and to generate spectral irradiance data for different locations and climates.

Riordan, C.J.

1986-02-01

342

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

343

Behavior of Helium Gas Bubbles in Neutron-Irradiated Beryllium  

Microsoft Academic Search

Transmission electron microscopic observations were made on hot-rolled Be sheet prepared from cast ingots irradiated to about 5 × 10 nvt(fast) in JRR-2.The aim of the study was to elucidate the effect of irradiation on changes in microstructure and the effect of pre-irradiation heat treatment on the formation of He gas bubbles during post-irradiation annealing.The formation and growth of He

Ryukichi NAGASAKI; Shozo OHASHI; Satoru KAWASAKI; Yoichi KARITA; Nobuo TSUNO

1971-01-01

344

Irradiation of ‘Boufeggous’ dates: Effects on chemical composition during storage  

Microsoft Academic Search

Moroccan dates Phoenix dactylifera L. cv. Boufeggous were treated with 0.6, 0.9 and 1.8kGy of gamma irradiation and subsequently stored at ambient temperatures. Chemical properties were evaluated for irradiated and non-irradiated dates immediately after the treatment, 4 and 8 months of storage. No significant changes were noted in dry matter, total lipid and protein contents. Irradiation at higher doses (0.9

Khalid Azelmat; Driss ElGarrouj; Mohammed Mouhib; Fouad Sayah

2006-01-01

345

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...

346

Post irradiation examination of irradiated americium oxide and uranium dioxide in magnesium aluminate spinel  

Microsoft Academic Search

To study MgAl2O4 spinel as inert matrix material for the transmutation of minor actinides, two capsules were irradiated at the high flux reactor in Petten, containing 12.5 wt% micro-dispersed 241AmOx in spinel and 25 wt% micro-dispersed enriched UO2 in spinel. During irradiation, the initially present 241Am was converted for 99.8% to fission products (50%), plutonium (30%), curium (16%) and 243Am

F. C Klaassen; K Bakker; R. P. C Schram; R Klein Meulekamp; R Conrad; J Somers; R. J. M Konings

2003-01-01

347

Gamma-ray irradiation and post-irradiation responses of high dose range RADFETs  

Microsoft Academic Search

Gamma-ray irradiation and post-irradiation responses have been studied for the two types of radiation sensitive p-channel MOSFETs (RADFETs) from different manufacturers. In addition to, in dosimetric applications standard, threshold voltage measurements at a single specified current, transistor I-V and charge-pumping characteristics have been monitored. This has been shown to be useful in providing a more detailed insight into processes that

A. Jaksic; G. Ristic; M. Pejovic; A. Mohammadzadeh; C. Sudre

2002-01-01

348

Gamma-ray irradiation and post-irradiation responses of high dose range RADFETs  

Microsoft Academic Search

Gamma-ray irradiation and post-irradiation responses have been studied for the two types of radiation sensitive p-channel MOSFETs (RADFETs) from different manufacturers. In addition to, in dosimetric applications standard, threshold voltage measurements at a single specified current, transistor I-V and charge-pumping characteristics have been monitored. This has been shown to be useful in providing a more detailed insight into processes that

A. Jaksic; G. Ristic; M. Pejovic; A. Mohammadzadeh; C. Sudre

2001-01-01

349

Tensile properties of irradiated nuclear grade pressure vessel welds for the third HSST irradiation series  

Microsoft Academic Search

The Heavy Section Steel Technology (HSST) Program conducted a series of experiments to investigate the effect of neutron irradiation on the fracture toughness of nuclear pressure vessel materials. Four welds of A 508 class 2 steel were examined in this Third HSST Irradiation Series. The welds were fabricated according to ''early'' (pre-1972) light-water reactor weld practice (i.e., copper-coated electrodes). As

McGowan

1985-01-01

350

Stereotactic irradiation without whole-brain irradiation for single brain metastasis  

Microsoft Academic Search

Purpose: The effectiveness of stereotactic irradiation (STI) alone without whole-brain irradiation (WBI) for a single metastatic brain tumor was analyzed retrospectively.Methods and Materials: Forty-four patients this condition were treated using radiosurgery (RS) alone or fractionated stereotactic radiotherapy (FSR) without WBI.Results: The initial response rate was 92% and the overall local control rate was 84% (37 of 44 patients). A total

Hiroki Shirato; Akio Takamura; Masayoshi Tomita; Keishiro Suzuki; Takashi Nishioka; Toyohiko Isu; Tsutomu Kato; Yutaka Sawamura; Keikichi Miyamachi; Hiroshi Abe; Kazuo Miyasaka

1997-01-01

351

Threonine-FX dosimeter for food irradiation  

NASA Astrophysics Data System (ADS)

A detailed study for the spectrophotometric readout method for L-threonine powder, [CH 3CH(OH)CH(NH 2)COOH], was done. In this method, 400 mg unirradiated/irradiated L-threonine powder was dissolved in 10 ml of a solution which contains 3×10 -4 mol dm -3 ferrous ammonium sulphate and 1.7×10 -4 mol dm -3 xylenol orange (XO) in aerated aqueous 0.17 mol dm -3 sulphuric acid (FX). The peroxy radicals produced from irradiated threonine oxidize ferrous ions and XO forms a complex with ferric ions as well as controls the chain length of ferrous ion oxidation. The plot of absorbance at 556 nm against dose is linear in the dose range 20-400 Gy and doses down to about 1 Gy can be measured using 10-cm path cells. Response of the dosimeter is independent of irradiation temperature above 20. A dose of 50 Gy-10 kGy can be measured dissolving 50 mg threonine powder in 10 ml of a solution which contains 3×10 -4 mol dm -3 ferrous ammonium sulphate and 1.3×10 -4 mol dm -3 XO in aerated aqueous 0.06 mol dm -3 sulphuric acid (FX). The plot of absorbance at 552 nm against dose is non-linear. However dosimeter shows linear dose response up to 1000 Gy. Irradiated threonine powder is stable for about 3 months. The reproducibility of the method is better than ±2%. This dosimeter is very useful as transfer dosimeter for food irradiation programme.

Nilekani, S. R.; Gupta, B. L.

2004-08-01

352

Ionospheric Change and Solar EUV Irradiance  

NASA Astrophysics Data System (ADS)

The ionosphere has been quantitatively monitored for the past six solar cycles. The past few years of observations are showing trends that differ from the prior cycles! Our good statistical relationships between the solar radio flux index at 10.7 cm, the solar EUV Irradiance, and the ionospheric F-layer peak density are showing indications of divergence! Present day discussion of the Sun-Earth entering a Dalton Minimum would suggest change is occurring in the Sun, as the driver, followed by the Earth, as the receptor. The dayside ionosphere is driven by the solar EUV Irradiance. But different components of this spectrum affect the ionospheric layers differently. For a first time the continuous high cadence EUV spectra from the SDO EVE instrument enable ionospheric scientists the opportunity to evaluate solar EUV variability as a driver of ionospheric variability. A definitive understanding of which spectral components are responsible for the E- and F-layers of the ionosphere will enable assessments of how over 50 years of ionospheric observations, the solar EUV Irradiance has changed. If indeed the evidence suggesting the Sun-Earth system is entering a Dalton Minimum periods is correct, then the comprehensive EVE solar EUV Irradiance data base combined with the ongoing ionospheric data bases will provide a most fortuitous fiduciary reference baseline for Sun-Earth dependencies. Using the EVE EUV Irradiances, a physics based ionospheric model (TDIM), and 50 plus years of ionospheric observation from Wallops Island (Virginia) the above Sun-Earth ionospheric relationship will be reported on.

Sojka, J. J.; David, M.; Jensen, J. B.; Schunk, R. W.

2011-12-01

353

Experimental plan for irradiation experiment HRB-21  

SciTech Connect

Irradiation experiment HRB-21 is the first in a series of test capsules that are designed to provide a fuel-performance data base to be used for the validation of modular high-temperature gas-cooled reactor (MHTGR) coated-particle fuel performance models under MHTGR normal operating conditions and specific licensing basis events. Capsule HRB-21 will contain an advanced TRISO-P UCO/ThO{sub 2} - coated-particle fuel system with demonstrated low defective-particle fraction ({le}5 {times} 10{sup {minus}5}) and a heavy metal-contamination fraction ({le}1 {times} 10{sup {minus}5}) that meets MHTGR quality specifications. The coated particles and fuel compacts were fabricated in laboratory-scale facilities using MHTGR reference procedures at General Atomics (GA). Nearly 150,000 fissile and fertile particles will be irradiated in capsule HRB-21 at a mean volumetric fuel temperature of 975{degree}C and will achieve a peak fissile burnup of 26% fissions per initial metal atom (FIMA) while accumulating a fast neutron fluence of about 4.5 {times} 10{sup 25} neutrons/m{sup 2}. This experiment is a cooperative effort between the US Department of Energy (DOE) and the Japan Atomic Energy Research Institute (JAERI). The participants are the Oak Ridge National Laboratory (ORNL), GA, and the Tokai Research Establishment. Capsule HRB-21 will contain the US MHTGR fuel specimens, and a companion capsule, HRB-22, will contain the JAERI fuel. The irradiation will take place in the removable beryllium reflector facility of the High Flux Isotope Reactor (HFIR) at ORNL. The performance of the fuel during irradiation will be closely monitored through on-line fission gas release measurements. Detailed postirradiation examination and conduction cooldown simulation testing will be performed on the irradiated fuel compacts from both the HRB-21 and HRB-22 capsules. 5 refs., 9 figs., 6 tabs.

Goodin, D. T. [General Atomics, San Diego, CA (United States); Kania, M. J.; Patton, B. W. [Oak Ridge National Lab., TN (United States)

1989-04-01

354

A Study of the Irradiation of Bacterial Spores By a Combined Gamma Irradiation-Heat Treatment in Different Leguminous Media; ETUDE DE L'IRRADIATION DES SPORES BACTERIENNES PAR UN TRAITEMENT COMBINE IRRADIATION GAMMACHALEUR DANS DIFFERENTS MILIEUX DE LEGUMES  

Microsoft Academic Search

The combined influence of gamma irradiation and thermal treatment on ihe ; inactivation of Clostridium sporogenes PA 3679 spores was confirmed. The gamma ; irradiation appreciably increases the spore sensitivity to heat. The effect of ; preheating followed by irradiation is less important but is not negligible. The ; spores of this organism are affected in a similar way in

M. De Proost; R. Pierard

1960-01-01

355

Effect of vitamin E on post irradiation death in mice  

Microsoft Academic Search

Summary The 30-day survival after exposure to 800 Rad60Co gamma radiation has been compared for female mice maintained on vitamin E deficient, vitamin E supplemented or regular lab rations before and\\/or after irradiation. Pre- or post-irradiation dietary supplementation had no effect on survival; however, injection ofa-tocopherol immediately after irradiation significantly reduced radiation lethality.

M. A. Malick; R. M. Roy; J. Sternberg

1978-01-01

356

?-Irradiation of Seeds and Productivity of Coriander, Coriandrum sativum L  

Microsoft Academic Search

Plant productivity and essential oil quality of coriander (Coriandrum sativuum L. cv. Alekseevsky 247) grown from ?-irradiated seeds was field tested in Bulgaria. The seeds, irradiated with 500 to 1500 rads using Co as the ?-irradiation source, produced plants yielding 14 to 25 percent more seed and 12 to 28 percent more oil than control plants grown from unirradiated seed.

E. A. Jeliazkova; L. E. Craker; V. D. Zheljazkov

1998-01-01

357

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

358

Void nucleation and phase stability in heavy ion irradiated materials  

Microsoft Academic Search

The response of a material to a fusion environment is one of the most important questions in fusion technology. Heavy ion irradiation can be used to further understanding of the microstructural evolution of an irradiated metal. Two aspects of heavy ion irradiation damage will be addressed: void nucleation and phase stability. A steady state void nucleation model was developed for

Plumton

1985-01-01

359

Tissue optics related with laser irradiation blood therapy  

Microsoft Academic Search

This paper introduces the research on the tissue optics related with the laser irradiation blood therapy. The optical parameters of Chinese blood and vascular tissue have been measured, including absorption coefficient, total attenuation coefficient, scattering coefficient and mean cosine of scattering angle. The model of intravascular low level laser irradiation therapy (ILLLI) and extravascular low level laser irradiation therapy (ELLLI)

Rong Chen; Yanjiao Chen; Shusen Xie; Buhong Li; Wei Zeng; Aizhen Ling; Qi Jin; Liting Ling; Shaofeng Xu

2000-01-01

360

Destabilization of olivine by 10kV electron irradiation  

Microsoft Academic Search

Mineral phases in the interplanetary medium are subjected to the solar wind irradiation. Irradiation induces fractional volatilization of chemical elements in silicates; if large scale directional flow occurs, such as predicted by numerous models in the early solar system, then large scale chemical fractionnations occur. Electron irradiation experiments were performed using a 30 keV electron beam on single crystals of

L. Lemelle; L. Beaunier; S. Borensztajn; M. Fialin; F. Guyot

2003-01-01

361

Sprout inhibition and radiomimetic properties in irradiated potatoes  

Microsoft Academic Search

Potato tubers of the up-to-date variety were irradiated with 20 krads of ; gamma rays using a 200-C Co⁶° source. The irradiated tubers were cold ; stored and then allowed to sprout. Sprouting was completely inhibited. Both ; irradiated and unirradiated tubers were used for the preparation of mash on which ; germinating barley embryos were planted. In root meristems

V. L. Chopra; M. S. Swaminathan

1963-01-01

362

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

363

Survival After Total Body Irradiation: Effects of Irradiation of Exteriorized Small Intestine. (Reannouncement with New Availability Information).  

National Technical Information Service (NTIS)

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 irrad...

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

1993-01-01

364

Utilization of Irradiation on Food Preservation. Preservation of Kimchi and Mixed Condiments for Convenience Food Processing by Irradiation.  

National Technical Information Service (NTIS)

The present project was intended to ascertain the efficacy of irradiation both in the decontamination and storeability of mixed condiments for convenience food and in the long-term preservation of a Kimchi. Based upon the preliminary studies, irradiated s...

H. O. Cho M. W. Byun J. H. Kwon S. W. Kim J. S. Yang

1987-01-01

365

Status of irradiations performed by fuel and target irradiation technology for BNW as of September 30, 1969.  

National Technical Information Service (NTIS)

This report itemizes the irradiations performed by Testing and Irradiation Services for Battelle-Northwest. It lists the material being awaiting disposition and material shipped during the report period. Information consists of: TISR No.; request number; ...

L. V. Barker

1969-01-01

366

Studies on safety and efficacy of gamma-irradiated ginseng -Development of irradiation techniques for quality improvement of ginseng products-.  

National Technical Information Service (NTIS)

Gamma irradiation was applied to red ginseng powder for improving microbiological and physicochemical quality. Irradiation at 5-10 kGy was effective for sterilizing all contaminated microorganisms of red ginseng powder. At the dose levels, major physicoch...

H. O. Cho M. W. Byun S. K. Cho I. J. Kand H. S. Yook

1995-01-01

367

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

SciTech Connect

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

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

2014-01-01

368

Irradiation creep of various ferritic alloys irradiated at ˜400°C in the PFR and FFTF reactors  

NASA Astrophysics Data System (ADS)

Irradiation creep of three ferritic alloys at ˜400 ?C has been studied. Specimens were in the form of pressurized tubes. In a joint US/UK creep study, two identical sets of creep specimens constructed from one heat of HT9 were irradiated in fast reactors, one in the Prototypic Fast Reactor (PFR) and the other in the Fast Flux Test Facility (FFTF). The specimens in PFR were irradiated to a dose of ˜50 dpa, whereas the specimens in FFTF were irradiated to a dose of 165 dpa. The observed swelling and creep behavior were very different in the two reactors. Creep specimens constructed from D57, a developmental alloy ferritic alloy, were also irradiated in PFR to a dose of ˜50 dpa. Creep behavior typical of previous studies on ferritic alloys was observed. Finally, creep specimens constructed from MA957, a Y 2O 3 dispersion-hardened ferritic alloy, were irradiated in FFTF to a dose of ˜110 dpa. This alloy exhibited a large amount of densification, and the creep behavior was different than observed in more conventional ferritic or ferritic-martensitic alloys.

Toloczko, M. B.; Garner, F. A.; Eiholzer, C. R.

1998-10-01

369

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

370

Irradiation resistance properties studies on helium ions irradiated MAX phase Ti3AlC2  

NASA Astrophysics Data System (ADS)

The study presents an investigation of irradiation resistance properties of Ti3AlC2 under 500 keV He ions irradiation with the doses ranging from 5.0 × 1016 to 1.0 × 1018 ions cm?2 at certain temperatures, like room temperature (RT), 300 and 500 °C. X-ray diffraction (XRD) and Transmission electron microscopy (TEM) are used to study the evolution of structural damage and the behavior of deposited He ions respectively. XRD analysis reveals that for the highest dose irradiation (˜52 dpa at peak), no amorphization occurs. And the structural recovery of Ti3AlC2 is more significant accompanied with the gradual disappearance of the irradiation-induced TiC phase as the temperature rises from RT to 300 and to 500 °C with the same dose irradiation. TEM observations show that He bubbles appear in the shapes of sphere, string and platelet but no big bubbles are formed for all irradiations. Moreover, no large cracks form in the sample implanted with the highest helium concentration of ˜6.4 × 105 appm.

Song, Peng; Sun, Jianrong; Wang, Zhiguang; Cui, Minghuan; Shen, Tielong; Li, Yuanfei; Pang, Lilong; Zhu, Yabin; Huang, Qing; Lü, Jinjun

2014-05-01

371

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

NASA Astrophysics Data System (ADS)

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

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

2014-05-01

372

The influence of fast neutron irradiation and irradiation temperature on the tensile properties of wrought LCAC and TZM molybdenum  

Microsoft Academic Search

The effects of irradiation temperature on embrittlement are evaluated by the irradiation of wrought low carbon arc cast (LCAC) and TZM molybdenum in the High Flux Isotope Reactor at 294–1100°C to neutron doses between 0.6 and 13.1dpaMo. Irradiation at 300°C is shown to result in elevation of the ductile to brittle transition temperature (DBTT) from a pre-irradiated value of ?100

B. V. Cockeram; R. W. Smith; L. L. Snead

2005-01-01

373

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

PubMed

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

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

2010-09-01

374

Stage III and localized stage IV breast cancer: irradiation alone vs irradiation plus surgery  

SciTech Connect

One hundred forty-seven patients with non-inflammatory, Stage III and IV breast cancer were treated with irradiation alone (54 patients) or with a combination of irradiation and mastectomy (93 patients). In the T/sub 3/ category, the local failure rate was 45% (5/11) for the irradiation alone patients vs 12% (3/25) for the irradiation plus surgery patients; in the T/sub 4/ category these figures were 65% (28/43) vs 13% (9/68), respectively. Corresponding local failure rates by size of primary tumor were 50% (2/4) vs 15% (5/29) for tumors 0-5 cm, 43% (0/21) vs 14% (6/45) for 5-8 cm tumors, and 75% (22/29) vs 5% (1/20) for tumors greater than or equal to8 cm. The rates of regional failure for the two treatment methods were compared according to N stage; they were 9% (2/23) for irradiation alone vs 11% (8/76) for irradiation plus surgery in the N/sub 0//sub -//sub 1/ category, and 58% (18/31) vs 18% (3/17), respectively, for the N/sub 2//sub -//sub 3/ category. A dose response analysis for patients with tumors greater than 5 cm treated with irradiation alone did not show a decrease in local failure rate with increasing total tumor dose over a range of 4000 to 7000 rad, suggesting that doses in this range are too low for these large tumors. Since a significant late complication rate has been reported with doses higher than this, patients with non-inflammatory, but large (>5 cm) tumors, should be treated with a combination of surgery and irradiation whenever possible to achieve maximum local-regional control with a minimum probability of complications. In 36 patients with inflammatory carcinoma, the rates of local and regional failure were 52% (15/29) and 38% (11/29), respectively, for patients treated with irradiation alone, and 14% (1/7) and 29% (2/7), respectively, for patients receiving irradiation plus surgery.

Bedwinek, J.; Rao, V.; Perez, C.; Lee, J.; Fineberg, B.

1981-01-01

375

Application of gamma irradiation for inhibition of food allergy  

NASA Astrophysics Data System (ADS)

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

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

2002-03-01

376

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

377

VUV irradiation studies of plasmid DNA in aqueous solution  

NASA Astrophysics Data System (ADS)

Interactions of VUV light and DNA samples in aqueous solutions are reported. The damage induced by such radiation is quantified by monitoring both loss of supercoiled DNA and formation of single and double strand breaks using agarose gel electrophoresis. Irradiations were performed using synchrotron VUV photons of 130, 150, 170 and 190 nm. VUV irradiation experiments revealed enhanced damage upon irradiation with 170 nm photons as compared with irradiations with photons of 150 nm and 130 nm. Irradiations carried at 190 nm caused the least damage.

?mialek, M. A.; Hoffmann, S. V.; Folkard, M.; Prise, K. M.; Shuker, D. E. G.; Braithwaite, N. S.; Mason, N. J.

2008-02-01

378

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

379

Low-fluence CO 2 laser irradiation decreases enamel solubility  

Microsoft Academic Search

This study investigated whether subablative-pulsed CO2 laser (10.6 ?m) irradiation, using fluences lower than 1 J\\/cm2, was capable of reducing enamel acid solubility. Fifty-one samples of bovine dental enamel were divided into three groups:\\u000a control group, which was not irradiated (CG); group laser A (LA) irradiated with 0.3 J\\/cm2; and group laser B (LB) irradiated with 0.7 J\\/cm2. After irradiation,

M. Esteves-Oliveira; C. Apel; N. Gutknecht; W. F. Velloso; M. E. B. Cotrim; C. P. Eduardo; D. M. Zezell

2008-01-01

380

Tissue optics related with laser irradiation blood therapy  

NASA Astrophysics Data System (ADS)

This paper introduces the research on the tissue optics related with the laser irradiation blood therapy. The optical parameters of Chinese blood and vascular tissue have been measured, including absorption coefficient, total attenuation coefficient, scattering coefficient and mean cosine of scattering angle. The model of intravascular low level laser irradiation therapy (ILLLI) and extravascular low level laser irradiation therapy (ELLLI) were developed. The light distribution in the vessel and blood of ILLLI is obtained by using Monte Carlo modeling calculation. Based on the light transmission of ELLLI, the optimum irradiation method and laser parameters are presented. This research is useful to the study of laser irradiation blood therapy and tissue optics.

Chen, Rong; Chen, Yanjiao; Xie, Shusen; Li, Buhong; Zeng, Wei; Lin, Aizhen; Jin, Qi; Ling, Liting; Xu, Shaofeng

2000-10-01

381

Spectral irradiance standard for the ultraviolet - The deuterium lamp  

NASA Technical Reports Server (NTRS)

A set of deuterium lamps is calibrated as spectral irradiance standards in the 200-350-nm spectral region utilizing both a high accuracy tungsten spectral irradiance standard and a newly developed argon mini-arc spectral radiance standard. The method which enables a transfer from a spectral radiance to a spectral irradiance standard is described. The following characteristics of the deuterium lamp irradiance standard are determined: sensitivity to alignment; dependence on input power and solid angle; reproducibility; and stability. The absolute spectral radiance is also measured in the 167-330-nm region. Based upon these measurements, values of the spectral irradiance below 200 nm are obtained through extrapolation.

Saunders, R. D.; Ott, W. R.; Bridges, J. M.

1978-01-01

382

Precipitate evolution in ion-irradiated HCM12A  

NASA Astrophysics Data System (ADS)

Precipitate evolution in HCM12A following proton irradiations to 3, 7 and 10 dpa at 400 °C, or following Fe++ irradiations to 100 and 500 dpa at 500 °C was studied. Ni/Si/Mn-rich precipitates were irradiation-induced and their nucleation was closely related to the local enrichment of Ni, Si and Mn at sinks such as dislocations due to radiation induced segregation. The composition of Ni/Si/Mn-rich precipitates evolved with irradiation dose and was different from that of the G-phase reported in irradiated ferritic-martensitic alloys. Nucleation of Cu-rich precipitates saturated after 3 dpa at 400 °C and coarsened at higher dose. Irradiation enhanced the precipitation of Cu-rich precipitates at 400 °C but suppressed the nucleation at 500 °C. Partial dissolution of Cu-rich precipitates must have occurred at 500 dpa at 500 °C as the volume fraction was smaller at 500 dpa than that at 100 dpa. Cr-rich precipitates were irradiation enhanced and were observed under irradiation at 400 °C but not observed at 500 °C due to the increase in Cr solubility with temperature. The evolution of Cr-rich precipitates with irradiation dose was likely related to the complex redistribution of Cr among chromium carbides, grain boundaries and matrix under irradiation. Radiation-induced Cr-rich carbides were observed following Fe++ irradiation to 500 dpa at 500 °C.

Jiao, Z.; Was, G. S.

2012-06-01

383

Emulation of neutron irradiation effects with protons: validation of principle  

NASA Astrophysics Data System (ADS)

This paper presents the results of the irradiation, characterization and irradiation assisted stress corrosion cracking (IASCC) behavior of proton- and neutron-irradiated samples of 304SS and 316SS from the same heats. The objective of the study was to determine whether proton irradiation does indeed emulate the full range of effects of in-reactor neutron irradiation: radiation-induced segregation (RIS), irradiated microstructure, radiation hardening and IASCC susceptibility. The work focused on commercial heats of 304 stainless steel (heat B) and 316 stainless steel (heat P). Irradiation with protons was conducted at 360 °C to doses between 0.3 and 5.0 dpa to approximate those by neutron irradiation at 275 °C over the same dose range. Characterization consisted of grain boundary microchemistry, dislocation loop microstructure, hardness as well as stress corrosion cracking (SCC) susceptibility of both un-irradiated and irradiated samples in oxygenated and de-oxygenated water environments at 288 °C. Overall, microchemistry, microstructure, hardening and SCC behavior of proton- and neutron-irradiated samples were in excellent agreement. RIS analysis showed that in both heats and for both irradiating particles, the pre-existing grain boundary Cr enrichment transformed into a `W' shaped profile at 1.0 dpa and then into a `V' shaped profile between 3.0 and 5.0 dpa. Grain boundary segregation of Cr, Ni, Si, and Mo all followed the same trends and agreed well in magnitude. The microstructure of both proton- and neutron-irradiated samples was dominated by small, faulted dislocation loops. Loop size distributions were nearly identical in both heats over a range of doses. Saturated loop size following neutron irradiation was about 30% larger than that following proton irradiation. Loop density increased with dose through 5.0 dpa for both particle irradiations and was a factor of 3 greater in neutron-irradiated samples vs. proton-irradiated samples. Grain boundary denuded zones were only observed in neutron-irradiated samples. No cavities were observed for either irradiating particle. For both irradiating particles, hardening increased with dose for both heats, showing a more rapid increase and approach to saturation for heat B. In normal oxygenated water chemistry (NWC) at 288 °C, stress corrosion cracking in the 304 alloy was first observed at about 1.0 dpa and increased with dose. The 316 alloy was remarkably resistant to IASCC for both particle types. In hydrogen treated, de-oxygenated water (HWC), proton-irradiated samples of the 304 alloy exhibited IG cracking at 1.0 dpa compared to about 3.0 dpa for neutron-irradiated samples, although differences in specimen geometry, test condition and test duration can account for this difference. Cracking in heat P in HWC occurred at about 5.0 dpa for both irradiating particles. Thus, in all aspects of radiation effects, including grain boundary microchemistry, dislocation loop microstructure, radiation hardening and SCC behavior, proton-irradiation results were in good agreement with neutron-irradiation results, providing validation of the premise that the totality of neutron-irradiation effects can be emulated by proton irradiation of appropriate energy.

Was, G. S.; Busby, J. T.; Allen, T.; Kenik, E. A.; Jensson, A.; Bruemmer, S. M.; Gan, J.; Edwards, A. D.; Scott, P. M.; Andreson, P. L.

2002-02-01

384

Stability of an injectable disulfiram formulation sterilized by gamma irradiation  

SciTech Connect

Stability of an injectable disulfiram suspension sterilized by gamma(gamma) irradiation was tested. Single doses of disulfiram powder in plastic syringes were subjected to 50,000 rads of gamma radiation. Culture media were inoculated with the irradiated drug to test for growth of bacteria, fungi, and mycobacteria. The irradiated drug and nonirradiated controls were analyzed by high-performance liquid chromatography (HPLC) for disulfiram and its major degradation product, diethyldithiocarbamate (DDC). Ultraviolet absorption spectra of irradiated and nonirradiated disulfiram were obtained. No organisms grew in any of the culture media. HPLC analysis indicated that disulfiram content of the irradiated specimens was not reduced, and DDC was not detected. There were no important differences between the ultraviolet spectra of the irradiated and nonirradiated samples. Disulfiram can be sterilized by gamma irradiation without chemical degradation.

Phillips, M.; Agarwal, R.P.; Brodeur, R.J.; Garagusi, V.F.; Mossman, K.L.

1985-02-01

385

Present status of refurbishment and irradiation technologies in JMTR  

NASA Astrophysics Data System (ADS)

The Japan Materials Testing Reactor (JMTR) of the Japan Atomic Energy Agency is a testing reactor for various neutron irradiation tests on nuclear fuels and materials, as well as for radioisotope production. The operation of JMTR stopped temporarily in August 2006 for refurbishment and improvement. The renewed JMTR will resume operation in Japanese fiscal year 2011. The renewal of aged reactor components, the preparation of new irradiation facilities, and the development of irradiation technologies have been carried out for the resumption of the new JMTR. The new JMTR with the new irradiation facilities and the irradiation technologies will be utilized for the research and development of fission and fusion reactor fuels and materials. This paper describes the present status of the refurbishment and the irradiation technologies focused on instrumentation such as the multi-paired thermocouple which is applicable to irradiation temperature control and a ceramic oxygen sensor in JMTR.

Inaba, Yoshitomo; Ishihara, Masahiro; Niimi, Motoji; Kawamura, Hiroshi

2011-10-01

386

Identification of gamma-irradiated papaya, melon and watermelon  

NASA Astrophysics Data System (ADS)

Ionizing radiation can be used to control spoilage microorganisms and to increase the shelf life of fresh fruits and vegetables in replacement for the treatment with chemical fumigants. In order to enforce labelling regulations, methods for detecting the irradiation treatment directly in the produce are required. Recently, a number of detection methods for irradiated food have been adopted by the Codex Comission. A rapid screening method for qualitative detection of irradiation is the DNA Comet Assay. The applicability of the DNA Comet Assay for distinguishing irradiated papaya, melon, and watermelon was evaluated. The samples were treated in a 60Co facility at dose levels of 0.0, 0.5, 0.75, and 1.0kGy. The irradiated samples showed typical DNA fragmentation whereas cells from non-irradiated ones appeared intact. In addition to the DNA Comet Assay also the half-embryo test was applied in melon and watermelon to detect the irradiation treatment.

Marín-Huachaca, Nélida S.; Mancini-Filho, Jorge; Delincée, Henry; Villavicencio, Anna Lúcia C. H.

2004-09-01

387

[Dosimetric comparison of external partial breast irradiation with whole breast irradiation and partial breast brachytherapy].  

PubMed

Different techniques exist for the delivery of radiotherapy after breast conserving surgery. The conventional method is whole breast irradiation. However, in selected patients partial breast irradiation can be performed, either with external beams or brachytherapy. In the current study three irradiation techniques are compared regarding dosimetric aspects. Treatment plans of thirty women treated with external beam conformal partial breast irradiation (CONF) were evaluated using dose-volume histograms. For the same patients whole breast irradiation plans (WBI) were made and compared with the CONF ones. Breast and lung of both sides, and heart at left sided lesions were contoured as organs at risk. After this, dose plans of another thirty patients treated with interstitial brachytherapy (IBT) were analyzed and compared with the CONF plans. According to our results the 90% isodose curve covered at least 97% of the target volume at all three techniques, and this value was 100% for CONF. The maximal dose within target volume was 106% in CONF and 115% in WBI plans. Volume of ipsilateral breast receiving the prescribed dose was 66%, 15% and 13% in the WBI, CONF and IBT plans, respectively. The dose to the contralateral breast was less for CONF compared to WBI. Volume of the ipsilateral lung receiving 30% of the prescribed dose was 15%, 8% and 1%, the maximal dose was 105%, 94% and 47% in the WBI, CONF and IBT plans, respectively. In the same order the maximal dose to the heart was 82%, 49% and 25%, while the dose irradiated to 5% of the heart volume was 27%, 19% and 14% at left sided lesions. Regarding target coverage, the conformal technique was the best, and the dose was more homogeneous than at WBI. With respect to dose to organs at risk the partial breast irradiation techniques were much more favorable than WBI, and the lowest doses occurred in the IBT treatment plans. PMID:25010759

Bodács, István; Polgár, Csaba; Major, Tibor

2014-07-01

388

Low-Temperature Thermally-Activated Deformation and Irradiation Softening in Neutron-irradiated Molybdenum  

SciTech Connect

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

Li, Meimei [ORNL; Byun, Thak Sang [ORNL; Snead, Lance Lewis [ORNL; Zinkle, Steven J [ORNL

2008-01-01

389

Stress relaxation of vitreous silica on irradiation  

SciTech Connect

The radiation-induced stress relaxation which is observed on ion bombardment of vitreous silica is described as a viscoelastic behavior in which the apparent viscosity is reduced to approx.10/sup 14/ Poise during irradiation and then increases rapidly by 4 or 5 orders of magnitude on cessation or interruption of irradiation. The bombarded layer appears to possess a viscosity approx.10/sup 19/ Poise, lower than would be expected for normal vitreous silica. On electron bombardment the viscosity is also reduced, but not as greatly as an ion bombardment, yet sufficiently to result in the whole radiation-induced volume contraction being realized perpendicularly to the surface, as has been found for ion bombardment. The maximum elastic stored energy which can be realized is but a fraction of a calorie per gram, hence the reported values of 200 cal/g would seem to be associated with the fragmentation of the network responsible for the reduced viscosity.

Primak, W.

1982-11-01

390

A Modal Analysis of the Irradiation Instability  

NASA Astrophysics Data System (ADS)

The irradiation instability is a disk instability caused by the radiation pressure cast by a central source onto an optically thick disk. The criterion for this instability depends on a sharp transition from an optically thin inner disk to an optically thick outer disk. The quickly diminishing radiation pressure in this transition region creates a radially compressing effect, which is in many ways similar to the effects of self-gravity. In this modal analysis, we demonstrate that a disk marginally stable to irradiation can develop global modes, with growth rates being of order the dynamical timescale of the disk. The non-linear evolution of the our model shows the formation of vortices near the transition region and spiral structures propagating into the optically thick region. Consequently the scale-height of our disk's inner edge becomes time-variable and can likely be observed as a variation in its infrared flux.

Fung, Jeffrey; Artymowicz, Pawel

2014-01-01

391

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

392

UVA system for human cornea irradiation  

NASA Astrophysics Data System (ADS)

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

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

2009-02-01

393

Solar Irradiance, Plage and SOHO UV Images  

NASA Astrophysics Data System (ADS)

Calcium K and H alpha plage and sunspot area have been monitored using Big Bear Observatory images on the INTERNET since November of 1992. The purpose of the project is to determine the correlation of changing plage area and solar irradiance changes. We also monitor changes in the K2 spec- tral index provided daily from Sacramento Peak. With the recent launching of the SOHO satellite, we are able to monitor the plage in the He II 304 Angstroms UV image. This image is near the top of the chromosphere nar or just under the transition region. The images show limb brightening as expected. Since it is widely believed that short time scale changes in the UV may be the dominant cause for low amplitude solar irradiance changes, the comparison of the "plage" ara in these UV images to those in conventional visible images should prove instructive.

Lopresto, James C.; Manross, Kevin

1996-05-01

394

Laser Assisted Cancer Immunotherapy: Surface Irradiation  

NASA Astrophysics Data System (ADS)

Experiments in our laboratory incorporate a non-invasive approach to treat superficial tumors in animal models. Based on the concept of Laser Assisted Cancer Immunotherapy, surface irradiation provides good information to compare to invasive alternatives. The procedure involves injecting an immunoadjuvant (Glycated Chitosan) as well as a light absorbing dye (Indocyanine Green) directly into the tumor (5 to 7 mm in diameter). The temperature of the tumor is raised using an infrared diode laser operating at 804 nm, with a silica fiber tip placed a set distance away from the surface of the tumor. We monitor the surface temperature using non-invasive (infrared detector probe) as well as the internal temperature of the tumor using invasive (micro thermocouples) methods. This study aims at the success of the surface irradiation mode to treat solid tumors. * This work is supported by a grant from The National Institute of Health.

Wilson, Joshua; Chen, Hsin-Wei; Bandyopadhyay, Pradip

2006-03-01

395

Breast irradiation and lactation: a review.  

PubMed

The incidence of breast cancer in premenopausal women is increasing and many of them still remain fertile after treatment. Allied to the current tendency to postpone pregnancy, it is expected that an increasing number of patients undergoing conservative treatment for breast cancer will get pregnant. Anatomical and histopathological aspects and the probability of lactation and breast feeding after breast irradiation are reviewed in this article. Lactation is possible after radiotherapy, present in at least 50% of the patients, but in reduced volume. This perspective is more correlated to the type of surgery and radiation dose used. Biochemical changes were observed in irradiated breast milk. Breastfeeding in the contralateral breast is not affected. PMID:23406557

Leal, Sarah Campos; Stuart, Silvia Radwanski; Carvalho, Heloisa de Andrade

2013-02-01

396

Remote Monitoring and Control of Irradiation Experiments  

SciTech Connect

As computer technology plays an increasing important role in particle accelerator facilities, instrumentation systems can be expected to include web connections and other remote capability features. The Michigan Ion Beam Laboratory at the University of Michigan in Ann Arbor has developed remote monitor and control capability by using a combination of commercial software packages and in-house software development. Irradiation parameters such as ion current on the samples and apertures, sample temperature read from an optical pyrometer, and chamber pressure can all be accessed and monitored remotely through a web site, as can ion source parameters such as power supply currents and voltages or feed gas pressure. With administrator permission, the control parameters of the ion source or the readouts from the irradiation stage can be modified in real time during an experiment. A description will be given of the various ways in which this type of remote monitoring and control has been accomplished at the Michigan Ion Beam Laboratory.

Toader, O.; Rotberg, V.H.; Was, G.S. [Michigan Ion Beam Laboratory, Department of Nuclear Engineering and Radiological Sciences, University of Michigan, Ann Arbor, MI 48109 (United States)

2003-08-26

397

Forward and reverse characteristics of irradiated MOSFETs  

SciTech Connect

pMOSFETs biased with V{sub gs} < V{sub gd} during Co{sup 60} {gamma} irradiation have shown substantial differences between the forward and reverse subthreshold characteristics, induced by a non-uniform charge distribution in the gate oxide. Correspondingly, modest differences have been observed in the over-threshold I-V characteristics. After irradiation, the forward subthreshold curves can shift at higher or lower gate voltages than the reverse ones. The former behavior has been observed in long-channel devices, in agreement with the classical MOS theory and numerical simulations. The latter result has been obtained in short-channel devices, and it has been correlated to a parasitic punch-through conduction mechanism.

Paccagnella, A.; Ceschia, M. [Univ. di Padova (Italy). Dipt. di Elettronica e Informatica] [Univ. di Padova (Italy). Dipt. di Elettronica e Informatica; Verzellesi, G.; Dalla Betta, G.F.; Soncini, G. [Univ. di Trento, Mesiano (Italy). Dipt. di Ingegneria dei Materiali] [Univ. di Trento, Mesiano (Italy). Dipt. di Ingegneria dei Materiali; Bellutti, P. [IRST, Povo (Italy)] [IRST, Povo (Italy); Fuochi, P.G. [CNR FRAE, Bologna (Italy)] [CNR FRAE, Bologna (Italy)

1996-06-01

398

Polyethylene welding by pulsed visible laser irradiation  

NASA Astrophysics Data System (ADS)

Laser welding of plastics is a relatively new process that induces locally a fast polymer heating. For most applications, the process involves directing a pulsed beam of visible light at the weld joint by going through one of the two parts. This is commonly referred to as "through transmission visible laser welding". In this technique, the monochromatic visible light source uses a power ns pulsed laser in order to irradiate the joint through one part and the light is absorbed in the vicinity of the other part. In order to evaluate the mechanical resistance of the welded joint, mass quadrupole spectrometry, surface profilometry, microscopy techniques and mechanical shear tests were employed. The welding effect was investigated as a function of the laser irradiation time, nature of the polyethylene materials and temperature.

Torrisi, L.; Caridi, F.; Visco, A. M.; Campo, N.

2011-01-01

399

Helium diffusion in irradiated boron carbide. [LMFBR  

SciTech Connect

Boron carbide has been internationally adopted as the neutron absorber material in the control and safety rods of large fast breeder reactors. Its relatively large neutron capture cross section at high neutron energies provides sufficient reactivity worth with a minimum of core space. In addition, the commercial availability of boron carbide makes it attractive from a fabrication standpoint. Instrumented irradiation experiments in EBR-II have provided continuous helium release data on boron carbide at a variety of operating temperatures. Although some microstructural and compositional variations were examined in these experiments most of the boron carbide was prototypic of that used in the Fast Flux Test Facility. The density of the boron carbide pellets was approximately 92% of theoretical. The boron carbide pellets were approximately 1.0 cm in diameter and possessed average grain sizes that varied from 8 to 30 ..mu..m. Pellet centerline temperatures were continually measured during the irradiation experiments.

Hollenberg, G.W.

1981-03-01

400

Electron irradiation damage in austenitic stainless steels  

NASA Astrophysics Data System (ADS)

Standard and Ti- and Nb-modified 316 SS specimens were irradiated with electrons in a high voltage electron microscope (HVEM) up to a dose of 40 dpa at 823 K. Void growth and carbide precipitate processes during irradiation were observed in situ and photographed. The experiment showed that 0.53% Ti-modified 316 SS had good resistance to void swelling, which is due to the small void size and low growth rate. The cold work did not increase the void swelling. In contrast, 0.49% and 0.78% Nb-modified 316 SS showed much higher void swelling than the others studied. However, the cold working of Nb-modified steels suppressed void swelling.

Sun, Jiguang; Qian, Jiapu; Zhao, Zhuoyong; Chen, Jiming; Xu, Zengyu

1991-03-01

401

Nanohardness and brittleness of irradiated spinel ceramics  

NASA Astrophysics Data System (ADS)

The influence of the size of crystalline regions on mechanical properties of irradiated oxides has been studied using magnesium aluminate spinel MgAl2O4. The samples characterized by different dimensions of crystalline domains, from sintered ceramics with grains of few micrometers in size up to single crystals, were used in the experiments. The samples were irradiated at room temperature with 320 keV Ar2+ ions up to fluences reaching 5 × 1016 cm-2. Nanomechanical properties were measured by using a nanoindentation technique and the resistance to crack formation by measurement of the total crack lengths made by Vickers indenter. The results revealed: correlation of nanohardness with accumulated damage, radiation-induced hardness increase in grain-boundary region and significant improvement of material resistance to crack formation.

Jagielski, J.; Aubert, P.; Maciejak, O.; Piatkowska, A.; Labdi, S.; Jozwik-Biala, I.; Jozwik, P.; Wajler, A.

2012-09-01

402

TEM study of neutron-irradiated iron  

SciTech Connect

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

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

1981-01-01

403

Laryngeal acinic cell carcinoma following thyroid irradiation  

SciTech Connect

Only three examples of acinic cell carcinoma of the larynx or trachea are found in the recent literature. A case of acinic cell carcinoma of the subglottic larynx and trachea was diagnosed and treated at the University of Virginia Medical Center. To our knowledge this is the first such case with a prior history of radiation to the neck. The patient is a 56-year-old woman who was irradiated for hyperthyroidism 46 years ago. When seen she also had parathyroid hyperplasia and multiple thyroid adenomas, conditions that frequently follow irradiation of the thyroid in children. These findings in this case support the concept that radiation may be responsible for inducing this tumor, which otherwise rarely occurs in this location. The use of electron microscopy was extremely useful in the diagnosis of this tumor. She was treated with total laryngectomy and right neck dissection and is now free of disease one year after surgery.

Reibel, J.F.; McLean, W.C.; Cantrell, R.W.

1981-01-01

404

Fall 2010 Total Solar Irradiance Calibration Workshop  

NASA Astrophysics Data System (ADS)

As part of a NASA-Sponsored program to understand the differences in Total Solar Irradiance (TSI) results reported by various space-based radiometers, the Naval Research Laboratory is hosting a Total Solar Irradiance Calibration Workshop. This workshop is a follow-on meeting to a similar workshop hosted by the National Institute for Standards and Technology in 2005. These workshops have been attended by many of the PI teams of the past and current TSI measuring instruments. The discussions at these workshops have addressed calibration methods and the numerous instrumental differences that need to be understood in order to bring the complete ensemble of results onto a common scale. In this talk we will present an overview of the NRL Calibration Workshop which will include results of recent calibration studies at various laboratories and have involved several TSI instruments.

Morrill, J. S.; Socker, D. G.; Willson, R. C.; Kopp, G.

2010-12-01

405

Swelling in neutron-irradiated titanium alloys  

SciTech Connect

Immersion density measurements have been performed on a series of titanium alloys irradiated in EBR-II to a fluence of 5 x 10/sup 22/n/cm/sup 2/ (E > 0.1 MeV) at 450 and 550/sup 0/C. The materials irradiated were the near-alpha alloys Ti-6242S and Ti-5621S, the alpha-beta alloy Ti-64, and the beta alloy Ti-38644. Swelling was observed in all alloys with the greater swelling being observed at 550/sup 0/C. Microstructural examination revealed the presence of voids in all alloys. Ti-38644 was found to be the most radiation resistant. Ti-6242S and Ti-5621S also displayed good radiation resistance, whereas considerable swelling and precipitation were observed in Ti-64 at 550/sup 0/C.

Peterson, D.T.

1982-04-01

406

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

407

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

408

Histologic changes in previously irradiated thyroid glands  

SciTech Connect

Thyroid tissue from 90 patients with a history of therapeutic irradiation to the head and neck in childhood and adolescence was examined microscopically. In addition to the well-known observation that these individuals have an increased incidence of primary thyroid carcinoma, it was also demonstrated that they have an increased incidence of benign histologic changes. These changes represent a spectrum from nonspecific hyperplastic lesions to benign neoplasis and thyroidltis.

Valdiserri, R.O.; Borochovitz, D.

1980-03-01

409

Operational solar irradiances for satellite drag applications  

Microsoft Academic Search

We report on major improvements to operational solar energy inputs for use in Jacchia-type empirical thermospheric density models to significantly improve Low Earth Orbit (LEO) satellite drag estimation. Three solar indices, compared to only one in the original Jacchia-type and MSIS-type models, best represent the complex interaction between a) the solar emission source (photosphere, chromosphere, corona), b) the irradiances' penetration

S. Bouwer; W. Tobiska

2006-01-01

410

Simulation of electron transport during beta irradiation  

Microsoft Academic Search

Optimisation of the laboratory beta irradiation for luminescence dosimetry requires a detailed understanding of the processes involved. For this purpose, we have developed a Monte-Carlo transport based model of the 90Sr\\/90Y source used on Risø TL\\/OSL readers. Here, we test this model against experimental data for an unshielded source. It is shown to be able to represent well the general

Steffen Greilich; Andrew S. Murray; Lars Bøtter-Jensen

2008-01-01

411

Irradiation behavior of pyrolytic silicon carbide. [HTGR  

Microsoft Academic Search

Fuel particles for the High-Temperature Gas-Cooled Reactor (HTGR) contain a layer of pyrolytic silicon carbide to act as a miniature pressure vessel and primary fission-product barrier. Optimization of the SiC with respect to fuel performance involves four areas of study: characterization of as-deposited SiC coatings; thermodynamics and kinetics of chemical reactions between SiC and fission products; irradiation behavior of SiC

Lauf

1983-01-01

412

Defect production rates in electron irradiated aluminium  

Microsoft Academic Search

The cross section for atomic displacement has been determined at 7.5°K by means of electrical resistivity measurements in electron irradiated aluminium up to transferred energies of 1100 eV. These data and those from the literature have been evaluated with respect to the displacement function (DF). Below 200 eV the DF could be derived from the data with sufficient accuracy by

J. Wurm; F. Dworschak; H. Schuster; H. Wollenberger

1970-01-01

413

Microstructural Self-Organization in Irradiated Systems  

Microsoft Academic Search

Irradiated metals and alloys are examples of open, dissipative systems far away from thermal equilibrium. In several cases they show self-organization of the microstructure resulting from non-linear reactions of the migrating point defects, i.e. vacancies and interstitials. In this review, the various published theoretical approaches to radiation-induced self-organization are discussed using a rate equation description. Two different mechanisms of defect

C. Abromeit

1989-01-01

414

Total lymphoid irradiation for multiple sclerosis  

SciTech Connect

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

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

1988-01-01

415

Post irradiation examination of thermal reactor fuels  

NASA Astrophysics Data System (ADS)

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

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

2008-12-01

416

Femoral neck fracture following groin irradiation  

Microsoft Academic Search

Purpose: The incidence and risk factors are evaluated for femoral rneck fracture following groin irradiation for gynecologic malignancies.Methods and Materials: The radiation therapy records of 1313 patients with advanced and recurrent cancer of the vagina, vulva, cervix, and endometrium, treated at the mallinckrodt Institute of Radiology from 1954 to 1992, were reviewed. Median follow-up was 12.7 years. From this group,

Perry W. Grigsby; Heidi L. Roberts; Carlos A. Perez

1995-01-01

417

Rotational Variability in Ultraviolet Solar Spectral Irradiance  

NASA Astrophysics Data System (ADS)

There are currently many observations and models of the Solar Spectral Irradiance (SSI) in the ultraviolet (UV). The models and the observations are often in agreement, but sometimes have significant differences. Using the decline of solar cycle 23 and the rise of solar cycle 24 as a test case, we will investigate the systematic differences between the short term SSI variation observed by satellite instruments and the predictions of proxy models.

Snow, M. A.; Richard, E. C.; Harder, J. W.; Thuillier, G. O.

2011-12-01

418

A CANDU-Based Fast Irradiation Reactor  

Microsoft Academic Search

A new steady-state fast neutron reactor is needed to satisfy the testing needs of Generation IV reactors, the Space Propulsion Program, and the Advanced Fuel Cycle Initiative. This paper presents a new concept for a CANDU-based fast irradiation reactor that is horizontal in orientation, with individual pressure tubes running the entire length of the scattering-medium tank (Calandria) filled with Lead-Bismuth-Eutectic

Shatilla

2006-01-01

419

Modeling structural metastability of irradiated thin films  

Microsoft Academic Search

The nucleation of crystalline or amorphous phases in irradiated binary metallic, as well as non-metallic compound thin films is interpreted using the atomistic interface migration-charge transfer (IMCT) model. The space and time evolution of dense collision cascades, which form upon ion bombardment of the target, lead to non-equilibrium compositional and electronic density profiles at the interface between each cascade and

P. M. Ossi

2004-01-01

420

Solute segregation in metals under irradiation  

Microsoft Academic Search

A kinetic model has been designed to study substitutional solute segregation during irradiation in facecentered-cubic metals. The model includes a split interstitial binding to impurities to second-neighbor distances, vacancy binding to impurities to first-neighbor distances, and the possibility of migration of the bound complexes. Also taken into account are the effects of vacancy and interstitial diffusional encounters with impurities and

Robert A. Johnson; Nghi Q. Lam

1976-01-01

421

Irradiation Modification of PVC\\/NBR Blend  

Microsoft Academic Search

Electron beam initiated cross-linking on the 50\\/50 poly(vinyl chloride), PVC\\/acrylonitrile butadiene rubber, NBR blend was studied in the absence and presence of 4 phr trimethylolpropane triacrylate (TMPTA). The 50\\/50 NBR\\/PVC blend was prepared by mixing in a Brabender Plasticoder at 170°C. The blend was then irradiated by using a 3.0 MeV electron beam machine at doses ranging from 0 to 200 kGy in

Chantara Thevy Ratnam; Sabariah Kamaruddin; Zahid Abdullah

2011-01-01

422

High-irradiance 248-nm laser system  

NASA Astrophysics Data System (ADS)

A laser system that routinely generates irradiances of 8 x 10 to the 17th W/sq cm is described. Pulses from a mode-locked visible dye laser are heterodyned to 248 nm and amplified in two KrF amplifiers. The output is 25-30 mJ in a 700-fsec pulse that can be focused to 5 sq microns.

Roberts, J. P.; Taylor, A. J.; Lee, P. H. Y.; Gibson, R. B.

1988-09-01

423

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

424

Proton irradiation of various resistivity silicon detectors  

SciTech Connect

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

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

1996-06-01

425

Stress modified welding process for irradiated materials  

SciTech Connect

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. (Auburn Univ., AL (United States)); Grossbeck, M.L. (Oak Ridge National Lab., TN (United States))

1992-01-01

426

Industrial irradiator radiation safety program assessments  

NASA Astrophysics Data System (ADS)

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

Smith, Mark A.

2000-03-01

427

Total scalp irradiation using helical tomotherapy  

SciTech Connect

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

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

2005-09-30

428

Dosimetry of biological irradiations using radiochromic films  

NASA Astrophysics Data System (ADS)

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

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

2013-05-01

429

Sequential half-body irradiation in childhood  

SciTech Connect

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

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

1983-12-01

430

Variability of UV irradiance in Europe.  

PubMed

The diurnal and annual variability of solar UV radiation in Europe is described for different latitudes, seasons and different biologic weighting functions. For the description of this variability under cloudless skies the widely used one-dimensional version of the radiative transfer model UVSPEC is used. We reconfirm that the major factor influencing the diurnal and annual variability of UV irradiance is solar elevation. While ozone is a strong absorber of UV radiation its effect is relatively constant when compared with the temporal variability of clouds. We show the significant role that clouds play in modifying the UV climate by analyzing erythemal irradiance measurements from 28 stations in Europe in summer. On average, the daily erythemal dose under cloudless skies varies between 2.2 kJ m(-2) at 70 degrees N and 5.2 kJ m(-2) at 35 degrees N, whereas these values are reduced to 1.5-4.5 kJ m(-2) if clouds are included. Thus clouds significantly reduce the monthly UV irradiation, with the smallest reductions, on average, at lower latitudes, which corresponds to the fact that it is often cloudless in the Mediterranean area in summer. PMID:18173717

Seckmeyer, Gunther; Pissulla, Darius; Glandorf, Merle; Henriques, Diamantino; Johnsen, Bjorn; Webb, Ann; Siani, Anna-Maria; Bais, Alkis; Kjeldstad, Berit; Brogniez, Colette; Lenoble, Jacqueline; Gardiner, Brian; Kirsch, Peter; Koskela, Tapani; Kaurola, Jussi; Uhlmann, Beate; Slaper, Harry; den Outer, Peter; Janouch, Michal; Werle, Peter; Gröbner, Julian; Mayer, Bernhard; de la Casiniere, Alain; Simic, Stana; Carvalho, Fernanda

2008-01-01

431

Diode laser irradiation treatment of thromboangitis obliterans  

NASA Astrophysics Data System (ADS)

The optical parameters for the treatment of thromboangitis obliterans were presented. The penetration characteristics of 650nm laser diode interaction with human vessel and blood were also studied respectively. The extra-vascular irradiation instrumentation using 650nm diode laser was developed based on the above investigation, and it can be applied for the treatment of thromboangitis obliterans and other diseases. In clinical application, out of the 10 patients, including 7 males and 3 females that suffered from throbmoangitis obliterans were treated with the extra- vascular irradiation instrumentation. 2 patients were suffered from upper limb, while the others were suffered from lower limb. Patient received 10 times treatment as a course, and the laser power for the first half-course was 20mW and ranged from 40mW to 80mW for the successively half- course. The total effective rate was 70 percent. A male patient in the third stage vasculitis of right foot without any improvement after treatment with traditional therapy but cured with diode laser irradiation after a course of treatment. The treatment mechanism of thromboangitis obliterans with diode laser was also briefly discussed.

Chen, Rong; Ye, Meiyun; Lin, Huiyun; Xu, Lanqing

2002-09-01

432

Dosimetry of biological irradiations using radiochromic films.  

PubMed

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

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

2013-05-21

433

Heavy ion irradiation of astrophysical ice analogs  

NASA Astrophysics Data System (ADS)

Icy grain mantles consist of small molecules containing hydrogen, carbon, oxygen and nitrogen atoms (e.g. H2O, CO, CO2, NH3). Such ices, present in different astrophysical environments (giant planets satellites, comets, dense clouds, and protoplanetary disks), are subjected to irradiation of different energetic particles: UV radiation, ion bombardment (solar and stellar wind as well as galactic cosmic rays), and secondary electrons due to cosmic ray ionization of H2. The interaction of these particles with astrophysical ice analogs has been the object of research over the last decades. However, there is a lack of information on the effects induced by the heavy ion component of cosmic rays in the electronic energy loss regime. The aim of the present work is to simulate of the astrophysical environment where ice mantles are exposed to the heavy ion cosmic ray irradiation. Sample ice films at 13K were irradiated by nickel ions with energies in the 1-10 MeV/u range and analyzed by means of FTIR spectrometry. Nickel ions were used because their energy deposition is similar to that deposited by iron ions, which are particularly abundant cosmic rays amongst the heaviest ones. In this work the effects caused by nickel ions on condensed gases are studied (destruction and production of molecules as well as associated cross sections, sputtering yields) and compared with respective values for light ions and UV photons.

Duarte, Eduardo Seperuelo; Domaracka, Alicja; Boduch, Philippe; Rothard, Hermann; Balanzat, Emmanuel; Dartois, Emmanuel; Pilling, Sergio; Farenzena, Lucio; da Silveira, Enio Frota

434

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

435

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

436

Hydrogen retention in ion irradiated steels  

SciTech Connect

In the future 1--5 MW Spallation Neutron Source, target radiation damage will be accompanied by high levels of hydrogen and helium transmutation products. The authors have recently carried out investigations using simultaneous Fe/He,H multiple-ion implantations into 316 LN stainless steel between 50 and 350 C to simulate the type of radiation damage expected in spallation neutron sources. Hydrogen and helium were injected at appropriate energy and rate, while displacement damage was introduced by nuclear stopping of 3.5 MeV Fe{sup +}, 1 {micro}m below the surface. Nanoindentation measurements showed a cumulative increase in hardness as a result of hydrogen and helium injection over and above the hardness increase due to the displacement damage alone. TEM investigation indicated the presence of small bubbles of the injected gases in the irradiated area. In the current experiment, the retention of hydrogen in irradiated steel was studied in order to better understand its contribution to the observed hardening. To achieve this, the deuterium isotope ({sup 2}H) was injected in place of natural hydrogen ({sup 1}H) during the implantation. Trapped deuterium was then profiled, at room temperature, using the high cross-section nuclear resonance reaction with {sup 3}He. Results showed a surprisingly high concentration of deuterium to be retained in the irradiated steel at low temperature, especially in the presence of helium. There is indication that hydrogen retention at spallation neutron source relevant target temperatures may reach as high as 10%.

Hunn, J.D.; Lewis, M.B.; Lee, E.H.

1998-11-01

437

Intermittency and variability of daily solar irradiation  

NASA Astrophysics Data System (ADS)

This paper deals the study of variability and intermittency of solar irradiation using an analogy with the turbulence and thus making use of some methodologies used in the study of intermittency of the turbulence. An analysis of the shape of the PDFs corresponding to the increments in the clearness and transmittance indexes, for direct and global radiations, is presented. In addition a study of the relations between the scaling exponents of the structure functions of the clearness and transmittance indexes and the orders of these structure functions has been carried out. According to the study, the range of relative variability is due to changes in the atmospheric components that play a role in the attenuation of solar irradiation. This range of variability is higher in the case of the global irradiation than in the case of the direct. Moreover, the multifractality is showed more intense in sites where, due to local effects, sharper variations in the radiation can be expected, as the case of deserts.

Vindel, J. M.; Polo, J.

2014-06-01

438

Raman spectroscopy of irradiated organic matter  

NASA Astrophysics Data System (ADS)

Raman spectroscopy of a range of irradiated and nonirradiated natural terrestrial bitumens has revealed that radiolytic alteration is generally associated with an increase in structural disorganisation. An interpretational methodology designed to overcome the considerable difficulties in obtaining reproducible, meaningful parameters of structural disorganisation is also presented, and should prove useful for future Raman applications. Raman investigation of a set of bitumens reported to have formed by the radiolytic polymerisation of light hydrocarbons, such as methane, has revealed excessive structural disorganisation, relative to biogenic complex-hydrocarbon-derived bitumens of similar radioelement concentrations, which may indicate the importance of precursor materials on the organic products of irradiation. Variations in the R1 ratio (D1/G band intensity) are found to be the best guide to variations in structural organisation. Comparisons of Raman spectra of the same sample, but produced by different exciting wavelengths, reveal the importance of the selection of a suitable laser wavelength. The results are discussed in terms of analyses of irradiated organic matter in the solar system, especially cometary nuclei and carbonaceous chondrites.

Court, Richard W.; Sephton, Mark A.; Parnell, John; Gilmour, Iain

2007-05-01

439

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

440

Flux and composition dependence of irradiation creep of austenitic alloys irradiated in PFR at ˜420°C  

NASA Astrophysics Data System (ADS)

Swelling and irradiation creep of five austenitic stainless steel alloys irradiated at ˜420°C in the Prototypic Fast Reactor (PFR) were examined. The specimens were in the form of pressurized creep tubes, constructed in the USA and irradiated in PFR in a joint USA/UK experiment. The alloy compositions varied greatly, with the greatest elemental variation in the nickel content, which ranged from 15% to 40% over the five alloys. For each alloy, at least two identical sets of tubes were constructed. Each tube-set was irradiated at a different neutron flux level. Swelling was observed to vary with both alloy composition and flux. Irradiation creep was examined from the perspective of the overlineB= ?¯?/ overline?=B 0+D ? creep model. The values of both creep coefficients, B0 and D, were typical for austenitic stainless steels and were found to be insensitive to flux over the range of fluxes in this experiment. However, the creep coefficients may be mildly sensitive to alloy composition.

Toloczko, M. B.; Garner, F. A.; Standring, J.; Munro, B.; Adaway, S.

1998-10-01

441

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

442

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

NASA Astrophysics Data System (ADS)

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 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 continuous coverage from 1981 to the present, while Lyman-alpha measurements, FISM daily data, and TSI models date from the 1940s to the present. LISIRD will also host Glory TSI data as part of the SORCE data system. 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’s interfaces.

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

2010-12-01

443

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

444

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

445

Evaluation of neutron irradiated silicon carbide and silicon carbide composites  

NASA Astrophysics Data System (ADS)

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™ Type-S, Hi-Nicalon™ or Sylramic™ fibers fabricated by chemical vapor infiltration. A statistically significant population of flexural samples were irradiated up to 4.6 × 10 25 n/m 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. The 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™ Type-S, while composites reinforced with Hi-Nicalon™ 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, George; Snead, Lance L.; Hinoki, Tatsuya; Katoh, Yutai; Peters, Dominic

2007-09-01

446

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

447

Effects of residual stress on irradiation hardening in stainless steels  

NASA Astrophysics Data System (ADS)

Effects of residual stress on irradiation hardening were studied in advance for predicting irradiation assisted stress corrosion cracking. The specimens of SUS316 and SUS316L with several % plastic strains, which correspond to weld residual stress, were prepared by bending and keeping deformation under irradiation. Ion irradiations of 12 MeV Ni 3+ were performed at 330, 400 and 550 oC to 45 dpa. No bended specimen was simultaneously irradiated with the bended specimen. The residual stress was estimated by X-ray residual stress measurements before and after the irradiation. The micro-hardness was measured by using nanoindenter. The residual stress did not relax even for the case of the higher temperature aging at 500 oC for the same time of irradiation. The residual stress after ion irradiation up to high dpa, however, relaxed at these experimental temperatures. The irradiation hardening of stressed specimen was obviously lower than that of un-stressed one in case of SUS316L irradiated at 300 oC to 12 dpa.

Okubo, N.; Miwa, Y.; Kondo, K.; Kaji, Y.

2009-04-01

448

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

NASA Astrophysics Data System (ADS)

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 irradiated reporter epithelial cells (HaCaT cell line). The main aim was to evaluate the overall effect of low dose irradiation (0.05 Gy) of reporter cells and the influence of bystander factors in plasma from 0.5 Gy gamma irradiated blood on these cells. The effects were estimated by clonogenic survival of the reporter cells. We also investigated the involvement of reactive oxygen species (ROS) as potential factors involved in the bystander signaling. Calcium fluxes and mitochondrial membrane potential (MMP) depolarization were also examined as a marker for initiation of apoptosis in the reporter cells. The results show that there are large individual differences in the production of bystander effects and adaptive responses between different donors. These may be due to the specific composition of the donor plasma. The observed effects generally could be divided into two groups: adaptive responses and additive effects. ROS appeared to be involved in the responses of the low dose pretreated reporter cells. In all cases there was a significant decrease in MMP which may be an early event in the apoptotic process. Calcium signaling also appeared to be involved in triggering apoptosis in the low dose pretreated reporter cells. The heterogeneity of the bystander responses makes them difficult to be modulated for medical uses. Specific plasma characteristics that cause these large differences in the responses would need to be identified to make them useful for radiotherapy.

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

2008-02-01

449

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

NASA Astrophysics Data System (ADS)

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

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

2014-06-01

450

Results of irradiation quality assurance of CMS silicon microstrip detectors  

NASA Astrophysics Data System (ADS)

The Large Hadron Collider (LHC) at CERN is a proton-proton collider with a maximum luminosity of 1034/cm2 s and will be working for 10 years. The Compact Muon Solenoid (CMS) will be one of the two general purpose detectors. In order to guarantee the functionality of the 24 328 single-sided silicon sensors in the heavy irradiation environment of the LHC a fraction of all sensors have been irradiated in the two Irradiation Qualification Centers (IQC) in Karlsruhe (Germany) and Louvain-la-Neuve (Belgium). In Karlsruhe the sensors are irradiated with 26 MeV protons and in Louvain-la-Neuve they are irradiated with a neutron spectrum with an average energy of 20 MeV. The following sections show observed coupling capacitances, bias resistances and interstrip capacitances before and after irradiation and after varying annealing times at 60C.

Furgeri, Alexander J.; de Boer, W.; Hartmann, F.

2007-04-01

451

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.; Krücken, R.; Strickfaden, H.; Dietzel, S.; Cremer, T.; Drexler, G. A.; Friedl, A. A.; Dollinger, G.

2009-06-01

452

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

453

Laser annealing of neutron irradiated boron-10 isotope doped diamond  

SciTech Connect

10B isotope doped p-type diamond epilayer grown by chemical vapor deposition on (110) oriented type IIa diamond single crystal substrate was subjected to neutron transmutation at a fluence of 2.4 9 1020 thermal and 2.4 9 1020 fast neutrons. After neutron irradiation, the epilayer and the diamond substrate were laser annealed using Nd YAG laser irradiation with wave length, 266 nm and energy, 150 mJ per pulse. The neutron irradiated diamond epilayer and the substrate were characterized before and after laser annealing using different techniques. The characterization techniques include optical microscopy, secondary ion mass spectrometry, X-ray diffraction, Raman, photoluminescence and Fourier Transform Infrared spectroscopy, and electrical sheet conductance measurement. The results indicate that the structure of the irradiation induced amorphous epilayer changes to disordered graphite upon laser annealing. The irradiated substrate retains the (110) crystalline structure with neutron irradiation induced defects.

Jagannadham, K. [North Carolina State University; Butler, J. E. [North Carolina State University

2011-01-01

454

Safety evaluation of irradiated foods in China: A condensed report  

SciTech Connect

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

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

1989-03-01

455

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

NASA Astrophysics Data System (ADS)

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

Cottee, Jim; Kunstadt, Peter; Fraser, Frank

1995-02-01

456

Long-term variations in total solar and UV irradiances  

NASA Technical Reports Server (NTRS)

The variations of total solar and UV irradiances during solar cycles 21 and 22 are compared. The total solar irradiance data used were obtained by the SMM/active cavity radiometer irradiance monitoring (ACRIM) 1, upper atmosphere research satellite (UARS)/ACRIM 2 and ERBS experiments. The space-based irradiance observations are compared to the Mount Wilson Magnetic Plage and Photometric Sunspot Index, which is derived from the area and position of sunspots published by the NOAA World Data Center Solar Geophysical Data Catalog. It is found that the variations in solar UV