Reheat cracking in austenitic stainless steels; Fissuration en relaxation des aciers inoxydables austenitiques

Energy Technology Data Exchange (ETDEWEB)

Auzoux, Q.; Allais, L. [CEA Saclay, Dept. des Materiaux pour le Nucleaire, DMN, 91 - Gif sur Yvette (France); Pineau, A.; Gourgues, A.F. [Centre des Materiaux Pierre-Marie Fourt UMR CNRS 7633, 91 - Evry (France)

2002-07-01

Intergranular cracking can occur in heat-affected zones (HAZs) of austenitic stainless steel welded joints when reheated in the temperature range from 500 to 700 deg C. At this temperature, residual stresses due to welding relax by creep flow. HAZ may not sustain this small strain if its microstructure has been sufficiently altered during welding. In order to precise which particular microstructure alteration causes such an intergranular embrittlement, type 316L(N) HAZs were examined by transmission electron microscopy. A marked increase in the dislocation density, due to plastic strain during the welding process, was revealed, which caused an increase in Vickers hardness. Type 316L(N) HAZ were then simulated by the following thermal-mechanical process: annealing treatment and work hardening (pre-strain). Creep rupture tests on smooth specimens were also carried out at 600 deg C on both base metal and simulated HAZ. Pre-straining increased creep strength but reduced ductility. Slow strain rate tests on CT specimens confirmed this trend as well as did relaxation tests on CT specimens, which led to intergranular crack propagation in the pre-strained material only. Metallography and fractography showed no qualitative difference between base metal and HAZs in the creep cavitation around intergranular carbides. Although quantitative study of damage development is not achieved yet, experiments suggest that uniaxial creep strain smaller than one percent could lead to cavity nucleation when the material is pre-strained. Pre-strain as well as stress triaxiality reduce therefore creep ductility and enhance the reheat cracking risk. (authors)

Évolution des contraintes résiduelles dans la couche de diffusion d’un acier modèle Fe-Cr-C nitruré

DEFF Research Database (Denmark)

Jegou, Sébastien; Barrallier, Laurent; Somers, Marcel A. J.

2011-01-01

Limiter la fatigue et la corrosion des pièces est possible grâce à une nitruration. Des contraintes résiduelles en découlent. Le rôle de la diffusion du carbone sur le développement de ces contraintes a été étudié sur un acier modèle Fe-3%m.Cr-0.35%m.C.......Limiter la fatigue et la corrosion des pièces est possible grâce à une nitruration. Des contraintes résiduelles en découlent. Le rôle de la diffusion du carbone sur le développement de ces contraintes a été étudié sur un acier modèle Fe-3%m.Cr-0.35%m.C....

Oxidation of steel heated in CO{sub 2} medium under pressure; Oxydation d'un acier ordinaire chauffe dans le gaz carbonique sous pression

Energy Technology Data Exchange (ETDEWEB)

Darras, R; Leclercq, D; Bunard, C [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

1958-07-01

Behaviour of low-alloyed steels heated in CO{sub 2} medium under pressure is reported. Tests are carried out in the range of erature reached in the CO{sub 2} cooled reactors (vessel, thermal shield, pipes). The observed weight increases are small, even after more than a thousand hours of heating at 350 deg. C, but oxidation curve looks like progressing linearly. Furthermore, the oxide formed under a pressure of 15 kg/cm{sup 2} is undoubtedly more compact and adherent than the one formed under a pressure of 1 kg/cm{sup 2}. Finally, for practical use, CO{sub 2} steel pipes surface has to be sand blast and pickled. A following phosphatizing protects it from atmospheric corrosion during assembling, but these treatments have no influence on the behaviour of these steels heated in CO{sub 2}. (author)Fren. [French] On etudie le comportement d'aciers au carbone faiblement allies, chauffes dans le gaz carbonique sous pression, aux temperatures atteintes dans les reacteurs refroidis par ce gaz (caisson, bouclier thermique, canalisations). Les augmentations de poids observees sont faibles, meme apres plus de 1000 heures de chauffage a 350 deg. C, mais l'oxydation semble se poursuivre lineairement. De plus, l'oxyde forme dans le gaz carbonique sous pression de 15 kg/cm{sup 2} est nettement plus compact et adherent que celui forme sous pression atmospherique de gaz carbonique. Enfin, dans la pratique, les surfaces d'acier du circuit de gaz carbonique sont necessairement sablees ou decapees; une phosphatation ulterieure le protege de la corrosion atmospherique pendant le montage. Ces traitements sont sans influence sur le comportement de ces aciers dans le gaz carbonique a chaud. (auteur)

CORROSION LOCALISEE DES ACIERS API 5L-X52 DE LA LIGNE ASR/MP SOLLICITE EN SOL ALGERIEN

OpenAIRE

BENDJEBBOUR, Amina

2011-01-01

L'étude porte sur les défaillances par corrosion localisée dans les aciers API de grade X52 de la ligne de pipelines ASR/MP acheminant les produits pétroliers sollicités en sol corrosif après échec des systèmes de protection anticorrosion (AC) à base de liants hydrocarbonés ou encore à base d'un système en multicouche complétée par une protection cathodique.

Iodine-131 production by a dry method using reactor-irradiated elementary tellurium. Part 1 - Conditions for obtaining iodine emanation and its capture. Part 2 - comparative study of preparation conditions using Pyrex, stainless steel and alumina equipment. Part 3 - production on a semi-industrial scale; Production de l'iode 131 par voie seche a partir de tellure elementaire irradie a la pile. 1ere partie - Etudes des conditions pour obtenir l'emanation de l'iode et le capter. 2eme partie - Etude comparee des conditions pour effectuer cette preparation avec des appareils en Pyrex, en acier inoxydable et en alumine. 3eme partie - production a l'echelle semi-industrielle

Energy Technology Data Exchange (ETDEWEB)

Bardy, A; Beydon, J; Murthy, T S; Doyen, J B; Lefrancois, J [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

1967-04-15

A previous report has described how iodine 131 can be prepared from elementary tellurium by a dry method which consists in treating irradiated tellurium at 400 degrees in argon. The possibility of carrying out this treatment in a stainless steel or alumina apparatus has been considered. The behavior of gaseous iodine 131 towards these materials has thus been studied. If the adsorption of iodine on stainless steel is superficial desorption is rapid at 250 degrees in oxygen or 400 degrees in argon. If the adsorption is chemical in nature it becomes necessary to heat to higher temperatures. Adsorption of iodine on alumina is very weak and the iodine can be desorbed rapidly. With these materials tests have been carried out on 300 gms of tellurium containing 41 curies of iodine 131; the yields were very satisfactory ( 98 per cent). (author) [French] La methode de preparation de l iode 131 par voie seche a partir de tellure elementaire decrite dans un precedent rapport consiste a traiter le tellure irradie a 400 degres sous argon. Nous avons examine la possibilite d effectuer ce traitement dans un appareil en acier inoxidable ou en alumine. Le comportement de l iode 131 gazeux vis a vis de ces materiaux a donc ete etudie. Si l adsorption de l iode sur l acier inoxidable est superficielle la desorption est rapide a 250 degres sous oxygene ou 400 degres sous argon. Si la fixation est de nature chimique il est necessaire de chauffer a des temperatures plus elevees. L adsorption de l iode sur l alumine est res faible et l iode peut etre desorbe rapideemnt. En employant ces materiaux des essais ont ete obtenus sur 300 g de tellure contenant 41 curies d iode 131 avec un bon rendement (98 pour cent). (auteur00.

Oxidation of steel heated in CO{sub 2} medium under pressure; Oxydation d'un acier ordinaire chauffe dans le gaz carbonique sous pression

Energy Technology Data Exchange (ETDEWEB)

Darras, R.; Leclercq, D.; Bunard, C. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

1958-07-01

Behaviour of low-alloyed steels heated in CO{sub 2} medium under pressure is reported. Tests are carried out in the range of erature reached in the CO{sub 2} cooled reactors (vessel, thermal shield, pipes). The observed weight increases are small, even after more than a thousand hours of heating at 350 deg. C, but oxidation curve looks like progressing linearly. Furthermore, the oxide formed under a pressure of 15 kg/cm{sup 2} is undoubtedly more compact and adherent than the one formed under a pressure of 1 kg/cm{sup 2}. Finally, for practical use, CO{sub 2} steel pipes surface has to be sand blast and pickled. A following phosphatizing protects it from atmospheric corrosion during assembling, but these treatments have no influence on the behaviour of these steels heated in CO{sub 2}. (author)Fren. [French] On etudie le comportement d'aciers au carbone faiblement allies, chauffes dans le gaz carbonique sous pression, aux temperatures atteintes dans les reacteurs refroidis par ce gaz (caisson, bouclier thermique, canalisations). Les augmentations de poids observees sont faibles, meme apres plus de 1000 heures de chauffage a 350 deg. C, mais l'oxydation semble se poursuivre lineairement. De plus, l'oxyde forme dans le gaz carbonique sous pression de 15 kg/cm{sup 2} est nettement plus compact et adherent que celui forme sous pression atmospherique de gaz carbonique. Enfin, dans la pratique, les surfaces d'acier du circuit de gaz carbonique sont necessairement sablees ou decapees; une phosphatation ulterieure le protege de la corrosion atmospherique pendant le montage. Ces traitements sont sans influence sur le comportement de ces aciers dans le gaz carbonique a chaud. (auteur)

Thermal fatigue cracking of austenitic stainless steels; Fissuration en fatigue thermique des aciers inoxydables austenitiques

Energy Technology Data Exchange (ETDEWEB)

Fissolo, A

2001-07-01

This report deals with the thermal fatigue cracking of austenitic stainless steels as AISI 316 LN and 304 L. Such damage has been clearly observed for some components used in Fast Breeder reactors (FBR) and Pressure Water Reactor (PWR). In order to investigate thermal fatigue, quasi-structural specimen have been used. In this frame, facilities enforcing temperature variations similar to those found under the operation conditions have been progressively developed. As for components, loading results from impeded dilatation. In the SPLASH facility, the purpose was to establish accurate crack initiation conditions in order to check the relevance of the usual component design methodology. The tested specimen is continuously heated by the passage of an electrical DC current, and submitted to cyclic thermal down shock (up to 1000 deg C/s) by means of periodical spraying of water on two opposite specimen faces. The number of cycles to crack initiation N{sub i} is deduced from periodic examinations of the quenched surfaces, by means of optical microscopy. It is considered that initiation occurs when at least one 50{mu}m to 150{open_square}m long crack is observed. Additional SPLASH tests were performed for N >> N{sub i}, with a view to investigate the evolution of a surface multiple cracking network with the number of cycles N. The CYTHIA test was mainly developed for the purpose of assessing crack growth dynamics of one isolated crack in thermal fatigue conditions. Specimens consist of thick walled tubes with a 1 mm circular groove is spark-machined at the specimen centre. During the test, the external wall of the tube is periodically heated by using a HF induction coil (1 MHz), while its internal wall is permanently cooled by flowing water. Total crack growth is derived from post-mortem examinations, whereby the thermal fatigue final rupture surface is oxidized at the end of the test. The specimen is broken afterwards under mechanical fatigue at room temperature. All the tests confirm that usual approaches are adapted in used conditions ( 280 {<=} T{sub max} {<=} 550 deg C, 100 {<=} {open_square}T {<=} 300 deg C): they are simply based on thermal loading mechanical loading equivalence. However, they appear not to be well adapted when additional factors exist such as roughness, residual stresses... Furthermore, Scanning Electron Microscopy observations show that damage is initiated well before the 'engineer initiation', as previously detected using optical microscopy on SPLASH specimen. First stage damage evolutions are thus a new task. Strain and stress fields generated during test are estimated thanks to finite element method computations (FEM), using CASTEM-2000 CEA software. Information coming from these FEM computations monitor lower-scale modelling: Discrete dislocation Dynamics (MICROMEGAS software). In order to continue that task, a new specimen has been adapted to the CYTHIA facility. Specimens consist of removable disks in which different and well-controlled conditions may be enforced. In order to estimate propagation of long crack, conventional fracture mechanic approach seems to be well adapted. The effective Stress Intensity Factor calculation takes into account of plastic strain. Furthermore, it is assumed that crack is opened during 60 % of cyclic loading. Shielding effect is clearly underlined by all the observations: on surface, on cross side section, and after sub-surface step-by-step removal. Multiple crack propagation (in the depth direction) is simulated using the previous single crack modelling. An auto-adaptative meshing allows simulating growth of 10 cracks up to 35,000 cycles. Two-development tasks are now in progress. The first task is oriented on the multiple crack growth and stability after an additional mechanical loading. The second task deals with the first damage stage up to the 'engineer crack initiation'. (author)

Etude des mécanismes d'interaction, au cours du procédé d'emboutissage à chaud, entre les surces atmosphériques d'hydrogène et les aciers à haute résistance revêtus d'Al-Si

OpenAIRE

Mandy, Mélodie; Jacques, Pascal; Georges, Cédric; Journée Jeunes Chercheurs 2015 - Commission "Corrosion sous contrainte / Fatigue-Corrosion"

2015-01-01

Dans l’industrie automobile, le défi permanent d’allègement en vue de diminuer la consommation de carburant est profitable tant au niveau économique qu’écologique. Pour permettre cette diminution de masse sans compromettre pour autant la sécurité des passagers, il est donc essentiel de développer des nuances d’aciers toujours plus résistantes. Néanmoins, ces aciers doivent également garder une certaine ductilité nécessaire à leur mise en forme, mais aussi fondamentale pour la sécurité des pas...

Évolution de la surface de plasticité sous chargement biaxial dans un acier inoxydable duplex

Science.gov (United States)

Aubin, V.; Quaegebeur, P.; Degallaix, S.

2002-12-01

Nous proposons une méthodologie de mesure automatique de la surface de plasticité pendant des chargements cycliques biaxiaux. La surface de plasticité est mesurée de manière discrète avec un faible offset de déformation plastique (2 10^{-5}) et des paramètres de mesure optimisés. La méthode est appliquée à un acier inoxydable duplex soumis à un trajet de chargement non-proportionnel. Les résultats montrent une distorsion et une translation de la surface de plasticité sans changement de taille. La méthode présentée permet également de vérifier la normalité de la vitesse d'écoulement plastique par rapport à la surface de plasticité.

Influence de la protection cathodique sur le comportement électrochimique des couches de corrosion d'acier au carbone

OpenAIRE

Tran Tron Long , Mai; Sutter , Eliane; Tribollet , Bernard

2013-01-01

11 pages, www.mattech-journal.org; International audience; Les propriétés électrochimiques de la couche de dépôts de corrosion formée à la surface des coupons d'acier E24 immergés pendant plusieurs années dans l'eau de mer sous différentes conditions de protection cathodique ont éteé'tudiées à l'aide de la spectroscopie d'impédance électrochimique et de mesures globale et locale de courant. Les résultats obtenus montrent que la couche de dépôts dont le comportement est déterminé par sa sous-c...

ECHAUFFEMENT ET EVOLUTION STRUCTURALE D’UN ACIER XC 42 LORS D’UN ESSAI DE TORSION A 700 °C

Directory of Open Access Journals (Sweden)

R BENSAHA

2001-12-01

Full Text Available Ce travail a pour but de montrer qu'il est possible d’apprécier la température et de développer un modèle simple de calcul de la recrudescence de la température en cours de déformation pour un acier XC 42 à une température d'essai  de 700°C et pour deux vitesses de déformation généralisées différentes de 5s-1 et 30s-1.                 Cette étude prend en considération, d'une part l'enthalpie  du changement de phase a®g  qui se libère au cours de la déformation dans l'intervalle de température A1-A3, et d'autre part, des mécanismes thermiquement activées (restauration et recristallisation dynamique mis en jeu lors de la déformation du matériau. Comme nos essais étaient pratiqués à la température de 700°C, proche de celle du point de transformation A1, les structures obtenues après trempe rapide montrent bien que pendant la déformation le matériau a subi la transformation de phase a®g, provoquée par l'auto échauffement de l'acier XC42. Le degré d'austénitisation est donc fonction de l'auto échauffement du matériau qui, à grande vitesse de déformation (227°C, est plus important qu'à faible vitesse (142°C.

Influence of plastic strain localization on the stress corrosion cracking of austenitic stainless steels; Influence de la localisation de la deformation plastique sur la CSC d'aciers austenitiques inoxydables

Energy Technology Data Exchange (ETDEWEB)

Cisse, S.; Tanguy, B. [CEA Saclay, DEN, SEMI, 91 - Gif-sur-Yvette (France); Andrieu, E.; Laffont, L.; Lafont, M.Ch. [Universite de Toulouse. CIRIMAT, UPS/INPT/CNRS, 31 - Toulous (France)

2010-03-15

The authors present a research study of the role of strain localization on the irradiation-assisted stress corrosion cracking (IASCC) of vessel steel in PWR-type (pressurized water reactor) environment. They study the interaction between plasticity and intergranular corrosion and/or oxidation mechanisms in austenitic stainless steels with respect to sublayer microstructure transformations. The study is performed on three austenitic stainless grades which have not been sensitized by any specific thermal treatment: the A286 structurally hardened steel, and the 304L and 316L austenitic stainless steels

Dynamical recrystallization of high purity austenitic stainless steels; Recristallisation dynamique d'aciers inoxydables austenitiques de haute purete

Energy Technology Data Exchange (ETDEWEB)

Gavard, L

2001-01-01

The aim of this work is to optimize the performance of structural materials. The elementary mechanisms (strain hardening and dynamical regeneration, germination and growth of new grains) occurring during the hot working of metals and low pile defect energy alloys have been studied for austenitic stainless steels. In particular, the influence of the main experimental parameters (temperature, deformation velocity, initial grain size, impurities amount, deformation way) on the process of discontinuous dynamical recrystallization has been studied. Alloys with composition equal to those of the industrial stainless steel-304L have been fabricated from ultra-pure iron, chromium and nickel. Tests carried out in hot compression and torsion in order to cover a wide range of deformations, deformation velocities and temperatures for two very different deformation ways have allowed to determine the rheological characteristics (sensitivity to the deformation velocity, apparent activation energy) of materials as well as to characterize their microstructural deformations by optical metallography and electron back-scattered diffraction. The influence of the initial grain size and the influence of the purity of the material on the dynamical recrystallization kinetics have been determined. An analytical model for the determination of the apparent mobility of grain boundaries, a semi-analytical model for the dynamical recrystallization and at last an analytical model for the stationary state of dynamical recrystallization are proposed as well as a new criteria for the transition between the refinement state and the state of grain growth. (O.M.)

Sub-micron indent induced plastic deformation in copper and irradiated steel; Deformation plastique induite par l'essai d'indentation submicronique, dans le cuivre et l'acier 316L irradie

Energy Technology Data Exchange (ETDEWEB)

Robertson, Ch

1999-07-01

In this work we aim to study the indent induced plastic deformation. For this purpose, we have developed a new approach, whereby the indentation curves provides the mechanical behaviour, while the deformation mechanisms are observed thanks to Transmission Electron Microscopy (TEM). In order to better understand how an indent induced dislocation microstructure forms, numerical modeling of the indentation process at the scale of discrete dislocations has been worked out as well. Validation of this modeling has been performed through direct comparison of the computed microstructures with TEM micrographs of actual indents in pure Cu (001]. Irradiation induced modifications of mechanical behaviour of ion irradiated 316L have been investigated, thanks to the mentioned approach. An important hardening effect was reported from indentation data (about 50%), on helium irradiated 316L steel. TEM observations of the damage zone clearly show that this behaviour is associated with the presence of He bubbles. TEM observations of the indent induced plastic zone also showed that the extent of the plastic zone is strongly correlated with hardness, that is to say: harder materials gets a smaller plastic zone. These results thus clearly established that the selected procedure can reveal any irradiation induced hardening in sub-micron thick ion irradiated layers. The behaviour of krypton irradiated 316L steel is somewhat more puzzling. In one hand indeed, a strong correlation between the defect cluster size and densities on the irradiation temperature is observed in the 350 deg. C - 600 deg. C range, thanks to TEM observations of the damage zone. On the other hand, irradiation induced hardening reported from indentation data is relatively small (about 10%) and shows no dependence upon the irradiation temperature (within the mentioned range). In addition, it has been shown that the reported hardening vanishes following appropriate post-irradiation annealing, although most of the TEM

TRANSFORMATION ISOTHERME D'UN ACIER A HAUTE RESISTANCE 40 CDV 13

Directory of Open Access Journals (Sweden)

A BOUTEFNOUCHET

2001-06-01

Full Text Available L'étude dilatométrique du comportement de l'austénite en condition isotherme d'un acier ternaire, à haute résistance mécanique de nuance 40 CDV 13, nous a permis de tracer son diagramme TTT. L'austénitisation a été réalisée pendant 10 minutes à  qg = 950°C (utilisée dans  l'industrie. Les températures de maintien sont comprises entre Ac1 = 810°C et Ms  = 310°C. Dans ce diagramme TTT, on distingue deux domaines de transformation isotherme de l'austénite. Le domaine I (625°C £  qiso < Ac1 = 810°C dans lequel l'austénite se transforme en ferrite et en perlite, et le domaine II (325°C  £  qiso £ 475°C où l'austénite se transforme en bainite ou en ferrite probainitique. Ces transformations sont précédées pour toutes les températures de maintien isotherme d'une précipitation de carbures. En outre, ces deux domaines de transformation de l'austénite sont séparés par une large zone de stabilité de l'austénite comprise entre 500°C et 600°C. L'analyse approfondie des courbes dilatométriques enregistrées durant le maintien isotherme et le refroidissement final jusqu'à l'ambiante, nous a permis de déterminer qualitativement et quantitativement les phase mises en jeu par ces transformations isothermes de l'austénite.

Welding hot cracking in an austenitic stainless steel; Fissuration a chaud en soudage d'un acier inoxydable austenitique

Energy Technology Data Exchange (ETDEWEB)

Kerrouault, N

2001-07-01

The occurrence of hot cracking is linked to several conditions, in particular, the composition of the material and the local strains due to clambering. The aim of this study is to better analyse the implied mechanisms and to lead to a local thermomechanical criterion for hot cracking. The example studied is an AISI 321-type stainless steel (X10CrNiTi18-12) strongly prone to cracking. Two weldability tests are studied: - the first one consists in carrying out a fusion line by the TIG process on a thin sheet. In the case of the defect occurrence, the crack is longitudinal and follows the back of the molten bath. The influence of the operating conditions welding (speed, welding heat input, width test sample) is studied. - the second one is the Varestraint test. It is widely used to evaluate the sensitivity of a material to hot cracking. It consists in loading the material by bending during a fusion line by the TIG process and in characterising the defects quantity (length, number). Various thermal and mechanical instrumentation methods were used. The possibilities of a local instrumentation instrumentation being limited because of the melting, the experimental results were complemented by a numerical modelling whose aim is to simulate the thermomechanical evolution of the loading thanks to the finite element analysis code ABAQUS. First, the heat input for thermal simulation is set by the use of an inverse method in order to optimise the energy deposit mode during welding in the calculation. Then, the mechanical simulation needs the input of a constitutive law that fits the mechanical behaviour over a wide temperature range from ambient to melting temperature. Thus, a mechanical characterization is performed by selecting strain values and strain rates representative of what the material undergoes during the tests. The results come from tensile and compressive tests and allow to settle an elasto-visco-plastic constitutive law over temperatures up to liquidus. Once validated, the thermomechanical simulation brings new interpretations of the tests observations and instrumentation results. The comparison of experimental and numerical results make it possible to determine a thermomechanical welding hot cracking criterion during solidification. This criterion simultaneously considers mechanical (strain and strain rates threshold) and thermal (temperature range, thermal gradient) parameters which give the position and orientation of the first crack initiation. The criterion precision are in good agreement with the observations on the two considered weldability tests. (author)

Contribution to the study of influences in emission spectrography on solutions. Application to a general analysis method for stainless steels (1961); Contribution a l'etude des influences en spectographie d'emission sur solution. Application a une methode generale d'analyse des aciers inoxydables (1961)

Energy Technology Data Exchange (ETDEWEB)

Baudin, G [Commissariat a l' Energie Atomique, Grenoble (France). Centre d' Etudes Nucleaires

1961-11-15

In order to establish a general method of analysis of stainless steels, by means of spark spectroscopy on solutions, a systematic study has been made of the factors involved. The variations in acidity of the solutions, or in the ratio of concentrations of two acids at constant pH, lead to a displacement of the calibration curve. Simple relations have been established between the concentration of the extraneous elements, and the effects produced, for the constituents Fe, Ti, Ni, Cr, Mn; a general method using abacus is proposed for steels containing only these elements. The interactions in the case of the elements Mo, Nb, Ta, W, were more complex, so that the simultaneous separation was studied with the help of ion-exchange resins. A general method of analysis is proposed for stainless steels. (author) [French] En vue d'etablir une methode generale d'analyse des aciers inoxydables par spectrographie d'etincelles sur solution, on a effectue une etude systematique des influences. Les variations de l'acidite des solutions ou du rapport des concentrations de deux acides a pH constant, entrainent un deplacement des courbes d'etalonnage. On a etabli des relations simples entre la teneur des tiers elements et les effets produits pour les constituants Fe, Ti, Ni, Cr, Mn; une methode generale avec abaques est proposee pour les aciers contenant ces seuls elements. Les influences dans le cas des elements Mo, Nb, Ta, W etant plus complexes, on eut a etudier la separation simultanee a l'aide de resines echangeuses d'ions. On propose une methode generale d'analyse des aciers inoxydables. (auteur)

Etude théorique et expérimentale de l’effet d’inhibition de la corrosion d’un acier au carbone par les dérivées de base de Schiff en milieu acide chlorhydrique

OpenAIRE

Khenadeki, Amine

2014-01-01

Dans cette étude,l'effet de l'addition de certais composés organique de dérivées de basses de schiff sur la corrosion d'un acier au carbone en milieu acide chlorhydrique a été étudié à l'aide des méthodes électrochimiques(courbes de polarisation et spectroscopie d'impédance électrochimique) et gravimétriques.........

Etude métallurgique du soudage par friction malaxage sur un acier à haute limite élastique destiné à la construction navale : le 80 HLES Metallurgical study of friction stir welding on a steel high yield for shipbuilding: The 80 HLES

Directory of Open Access Journals (Sweden)

Allart Marion

2013-11-01

Full Text Available Le soudage par friction malaxage est un procédé de soudage relativement récent (début des années 90. Il est aujourd'hui utilisé couramment sur des alliages légers mais ne l'est que depuis peu sur les aciers. L'objectif de nos travaux est de chercher à caractériser la microstructure métallurgique et l'état de déformation et de contrainte après soudage par friction malaxage sur des échantillons d'aciers à haute limite élastique utilisés dans l'industrie navale. Nous chercherons à comprendre les phénomènes métallurgiques qui interviennent en cours de soudage. The friction stir welding is a welding process relatively recent (early 90s. It is now commonly used on light alloys but is only recently on steels. The objective of our work is to try to characterize the metallurgical microstructure and state of stress and strain after friction stir welding on samples of high strength steels used in the shipbuilding industry. We seek to understand the metallurgical phenomena that occur during welding.

Wear studies in the shearing process by means of irradiated tools; Etudes d'usure dans les operations de cisaillement, au moyen d'outils irradies; Issledovaniya problemy iznosa v protsesse skalyvaniya posredstvom obluchennykh instrumentov; Estudios de desgaste en las operaciones de cizallamiento, realizados con ayuda de herramientas irradiadas

Energy Technology Data Exchange (ETDEWEB)

Sata, Toshio; Abe, Kunio; Nakajima, Kiyoshi [Institute of Physical and Chemical Research, Komagome, Bunkyo-Ku, Tokyo (Japan)

1962-01-15

Tool wear in the shearing of sheet metals was studied with punches and dies of high-speed steel irradiated in an atomic pile. Circular discs 10 mm in diameter were punched from 0.5-mm-thick low-carbon steel, stainless steel and silicon steel in dry and lubricated states. After punching, the radioactivity of the discs and the holes was measured. When the radioactive die was replaced by a non-active one, little radioactivity was detected on the discs, while the radioactivity of the holes scarcely varied. This proved that the wear of the die can be found from the radioactivity of the discs, and that of the punch from the radioactivity of the holes. By this method the wear of the punch and die was followed by using different lubricants and sheet metals with the following results: (1) At the beginning of punching, the wear rates of both punch and die are very large but rapidly decrease, becoming eventually stationary after punching about four to five hundred pieces. (2) The wear rate of the punch is about 20% greater than that of the die. (3) Lubricants with extreme pressure additives, such as chlorine, phosphorus or sulphur, reduce tool wear, while refined mineral oils give little improvement. (4) The heaviest tool wear occurs when punching the harder sheet metals. Tool wear for stainless steel is about three times, and for silicon steel about six times, as large as for low-carbon steel. (author) [French] On a etudie l'usure des outils utilises pour le cisaillement de plaques de metal en se servant de poincons et de matrices en acier rapide irradies dans line pile atomique. Des pastilles de 10 mm de diametre ont ete decoupees, a sec et avec lubrifiants, dans des toles de 0,5 mm d'epaisseur d'acier pauvre en carbone, d'acier inoxydable et d'acier riche en silicium. Apres le poinconnage, on a mesure la radioactivite des pastilles et des trous. Lorsqu'on remplacait la matrice radioactive par une autre non radioactive, on ne detectait guere de radioactivite sur les

Crack growth in an austenitic stainless steel at high temperature; Propagation de fissure a haute temperature dans un acier inoxydable austenitique

Energy Technology Data Exchange (ETDEWEB)

Polvora, J.P

1998-12-31

This study deals with crack propagation at 650 deg C on an austenitic stainless steel referenced by Z2 CND 17-12 (316L(NN)). It is based on an experimental work concerning two different cracked specimens: CT specimens tested at 650 deg C in fatigue, creep and creep-fatigue with load controlled conditions (27 tests), tube specimens containing an internal circumferential crack tested in four points bending with displacement controlled conditions (10 tests). Using the fracture mechanics tools (K, J and C* parameters), the purpose here is to construct a methodology of calculation in order to predict the evolution of a crack with time for each loading condition using a fracture mechanics global approach. For both specimen types, crack growth is monitored by using a specific potential drop technique. In continuous fatigue, a material Paris law at 650 deg C is used to correlate crack growth rate with the stress intensity factor range corrected with a factor U(R) in order to take into account the effects of crack closure and loading ratio R. In pure creep on CT specimens, crack growth rate is correlated to the evolution of the C* parameter (evaluated experimentally) which can be estimated numerically with FEM calculations and analytically by using a simplified method based on a reference stress approach. A modeling of creep fatigue growth rate is obtained from a simple summation of the fatigue contribution and the creep contribution to the total crack growth. Good results are obtained when C* parameter is evaluated from the simplified expression C*{sub s}. Concerning the tube specimens tested in 4 point bending conditions, a simulation based on the actual A 16 French guide procedure proposed at CEA. (authors) 104 refs.

Crack initiation at high temperature on an austenitic stainless steel; Amorcage de fissure a haute temperature dans un acier inoxydable austenitique

Energy Technology Data Exchange (ETDEWEB)

Laiarinandrasana, L

1994-11-25

The study deals with crack initiation at 600 and 650 degrees Celsius, on an austenitic stainless steel referenced by Z2 CND 17 12. The behaviour laws of the studied plate were update in comparison with existing data. Forty tests were carried out on CT specimens, with continuous fatigue with load or displacement controlled, pure creep, pure relaxation, creep-fatigue and creep-relaxation loadings. The practical initiation definition corresponds to a small crack growth of about the grain size. The time necessary for the crack to initiate is predicted with fracture mechanics global and local approaches, with the helps of microstructural observations and finite elements results. An identification of a `Paris`law` for continuous cyclic loading and of a unique correlation between the initiation time and C{sup *}{sub k} for creep tests was established. For the local approach, crack initiation by creep can be interpreted as the reaching of a critical damage level, by using a damage incremental rule. For creep-fatigue tests, crack growth rates at initiation are greater than those of Paris`law for continuous fatigue. A calculation of a transition time between elastic-plastic and creep domains shows that crack initiation can be interpreted whether by providing Paris`law with an acceleration term when the dwell period is less than the transition time, or by calculating a creep contribution which relies on C{sup *}{sub k} parameter when the dwell period and/or the initiation times are greater than the transition time. Creep relaxation tests present crack growth rates at initiation which are less than those for `equivalent` creep-fatigue tests. These crack growth rates when increasing hold time, but also when temperature decreases. Though, for hold times which are important enough and at lower temperature, there is no effect of the dwell period insofar as crack growth rate is equal to continuous fatigue Paris law predicted ones. (Abstract Truncated)

MODÉLISATION DES FLUX DE CHALEUR GÉNÉRÉS PAR FROTTEMENT GLISSANT DANS UN CONTACT CUIVRE-ACIER TRAVERSÉ PAR UN COURANT ÉLECTRIQUE

Directory of Open Access Journals (Sweden)

A BOUCHOUCHA

2001-06-01

Full Text Available Le problème de la conduction de la chaleur dans un contact électrique glissant cuivre–acier est étudié. Le couple fonctionne dans des conditions atmosphériques et est donc refroidi par convection naturelle à travers les faces latérales. En utilisant l'équation de la chaleur, un modèle de calcul de la température interfaciale a été élaboré. A l'aide de la méthode des volumes finis, les résultats de la température en fonction de la charge normale, la vitesse de glissement et le courant électrique sont donnés. Une comparaison avec la méthode d'Archard est faite. Les résultats montrent une bonne concordance. Une discussion globale du modèle élaboré et son application dans les contacts électriques glissants a été dégagée.

EFFET DES TRAITEMENTS THERMIQUES SUR LA REACTION ENTRE DES COUCHES MINCES DE TITANE ET DES SUBSTRATS EN ACIER

Directory of Open Access Journals (Sweden)

D Slimani

2015-06-01

Full Text Available Des couches minces du titane pur ont été déposées avec la méthode de pulvérisation cathodique sur des substrats en acier, type FF80 K-1 contenants ~1% mass. en carbone. La réaction entre les deux parties du système substrat-couche mince est activée avec des traitements thermiques sous vide dans l’intervalle de températures de 400 à900°Cpendant 30 minutes. Les Spectres de diffraction de rayons x confirment l’inter- diffusion des éléments  chimiques du système résultants la formation et la croissance des nouvelles phases en particulier le carbure binaire TiC ayant des caractéristiques thermomécaniques importantes. L’analyse morphologique des échantillons traités  avec le microscope électronique à balayage (MEB montre l’augmentation du flux de diffusion atomique avec la température de recuit, notamment la diffusion du manganèse et du fer vers la surface libre des échantillons aux températures élevées provoquant la dégradation des propriétés mécaniques des revêtements contrairement au premiers stades d’interaction où on a obtenu des bonnes valeurs de la microdureté.

Stress relief cracking by relaxation in austenitic stainless steels welded junctions; Fissuration differee par relaxation des jonctions soudes en aciers inoxydables austenitiques

Energy Technology Data Exchange (ETDEWEB)

Allais, L.; Auzoux, Q.; Chabaud-Reytier, M

2003-07-01

During service at high temperature (450 to 650 C), austenitic stainless steels are well known to present a risk of cracking near the welded junctions for times under the service life. This intergranular cracking in affected zones has been identified on titanium stabilized steels and is known as relief cracking by relaxation or reheat cracking. In order to control this cracking of welded junctions on titanium stabilized stainless steel AISI 321, a simulation of the affected zone has been realized. The results have been extended to non stabilized steels. (A.L.B.)

Device for recovering radioactive waste; Dispositif de recuperation d'effluents radioactifs

Energy Technology Data Exchange (ETDEWEB)

Mas, R [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

1965-07-01

The previous system which consisted in the use of metallic reservoirs placed in a concrete-lined pit gave rise to certain incidents due to corrosion or overflowing followed by contamination with serious consequences. The new system presented consists essentially of a standard 3 m{sup 3} reservoir of stainless steel which is fixed in a concrete-lined well, is tubed with stainless steel. Each reservoir has a standard lid on which are placed all the accessory devices, themselves standardized. The new reservoirs offer thus a great degree of security, and are interchangeable; the wells are easy to decontaminate and it is possible to work in a well without any danger of the personnel being irradiated by neighbouring reservoirs. (author) [French] L'ancien systeme de cuves metalliques disposees dans une fosse betonnee a donne lieu a des incidents par corrosion ou debordements suivis de contamination ayant de grosses consequences. Le nouveau systeme presente comporte essentiellement une cuve standard de 7 m{sup 3} en acier inoxydable mise en place et ancree dans un puits betonne et cuvele en acier inoxydable. Chaque cuve comporte un couvercle standard sur lequel sont rassembles tous les dispositifs annexes standardises eux aussi. Les nouvelles cuves sont donc sures, interchangeables, les puits sont faciles a decontaminer et le travail dans un puits est possible sans crainte d'irradiation du personnel par les cuves voisines. (auteur)

Soudage hybride Laser-MAG d'un acier Hardox® Hybrid Laser Arc Welding of a Hardox® steel

Directory of Open Access Journals (Sweden)

Chaussé Fabrice

2013-11-01

Full Text Available Le soudage hybride laser-MAG est un procédé fortement compétitif par rapport aux procédés conventionnels notamment pour le soudage de fortes épaisseurs et les grandes longueurs de soudure. Il connait de ce fait un développement important dans l'industrie. La présente étude s'est portée sur la soudabilité de l'acier Hardox® par ce procédé. Un large panel de techniques de caractérisation a été employé (mesures thermiques, radiographie X, duretés Vickers, macrographie…. L'objectif étant de déterminer l'influence des paramètres du procédé sur la qualité de la soudure et d'étendre notre compréhension des phénomènes se déroulant lors de ce type de soudage. Hybrid Laser Arc Welding (HLAW technology is a highly competitive metal joining process especially when high productivity is needed and for the welding of thick plates. It is a really new technology but its implementation in industry accelerates thanks to recent improvements of high power laser equipment and development of integrated hybrid welding heads. This study focuses on weldability of Hardox® 450 steel by HLAW. Welding tests were conducted by making critical process parameters vary. Then a large panel of characterization techniques (X-Ray radiography, macroscopic examination and hardness mapping was used to determine process parameters influence on weldability of Hardox 450® Steel.

Atom probe study of the microstructural evolution induced by irradiation in Fe-Cu ferritic alloys and pressure vessel steels; Etude a la sonde atomique de l`evolution microstructurale sous irradiation d`alliages ferritiques Fe-Cu et d`aciers de cuve REP

Energy Technology Data Exchange (ETDEWEB)

Pareige, P

1996-04-01

Pressure vessel steels used in pressurized water reactors are low alloyed ferritic steels. They may be prone to hardening and embrittlement under neutron irradiation. The changes in mechanical properties are generally supposed to result from the formation of point defects, dislocation loops, voids and/or copper rich clusters. However, the real nature of the irradiation induced-damage in these steels has not been clearly identified yet. In order to improve our vision of this damage, we have characterized the microstructure of several steels and model alloys irradiated with electrons and neutrons. The study was performed with conventional and tomographic atom probes. The well known importance of the effects of copper upon pressure vessel steel embrittlement has led us to study Fe-Cu binary alloys. We have considered chemical aging as well as aging under electron and neutron irradiations. The resulting effects depend on whether electron or neutron irradiations ar used for thus. We carried out both kinds of irradiation concurrently so as to compare their effects. We have more particularly considered alloys with a low copper supersaturation representative of that met with the French vessel alloys (0.1% Cu). Then, we have examined steels used on French nuclear reactor pressure vessels. To characterize the microstructure of CHOOZ A steel and its evolution when exposed to neutrons, we have studied samples from the reactor surveillance program. The results achieved, especially the characterization of neutron-induced defects have been compared with those for another steel from the surveillance program of Dampierre 2. All the experiment results obtained on model and industrial steels have allowed us to consider an explanation of the way how the defects appear and grow, and to propose reasons for their influence upon steel embrittlement. (author). 3 appends.

Prediction du profil de durete de l'acier AISI 4340 traite thermiquement au laser

Science.gov (United States)

Maamri, Ilyes

Les traitements thermiques de surfaces sont des procedes qui visent a conferer au coeur et a la surface des pieces mecaniques des proprietes differentes. Ils permettent d'ameliorer la resistance a l'usure et a la fatigue en durcissant les zones critiques superficielles par des apports thermiques courts et localises. Parmi les procedes qui se distinguent par leur capacite en terme de puissance surfacique, le traitement thermique de surface au laser offre des cycles thermiques rapides, localises et precis tout en limitant les risques de deformations indesirables. Les proprietes mecaniques de la zone durcie obtenue par ce procede dependent des proprietes physicochimiques du materiau a traiter et de plusieurs parametres du procede. Pour etre en mesure d'exploiter adequatement les ressources qu'offre ce procede, il est necessaire de developper des strategies permettant de controler et regler les parametres de maniere a produire avec precision les caracteristiques desirees pour la surface durcie sans recourir au classique long et couteux processus essai-erreur. L'objectif du projet consiste donc a developper des modeles pour predire le profil de durete dans le cas de traitement thermique de pieces en acier AISI 4340. Pour comprendre le comportement du procede et evaluer les effets des differents parametres sur la qualite du traitement, une etude de sensibilite a ete menee en se basant sur une planification experimentale structuree combinee a des techniques d'analyse statistiques eprouvees. Les resultats de cette etude ont permis l'identification des variables les plus pertinentes a exploiter pour la modelisation. Suite a cette analyse et dans le but d'elaborer un premier modele, deux techniques de modelisation ont ete considerees, soient la regression multiple et les reseaux de neurones. Les deux techniques ont conduit a des modeles de qualite acceptable avec une precision d'environ 90%. Pour ameliorer les performances des modeles a base de reseaux de neurones, deux

Study of structural modifications induced by ion implantation in austenitic stainless steel; Etude des modifications structurales induites par implantation ionique dans les aciers austenitiques

Energy Technology Data Exchange (ETDEWEB)

Dudognon, J

2006-12-15

Ion implantation in steels, although largely used to improve the properties of use, involves structural modifications of the surface layer, which remain still prone to controversies. Within this context, various elements (N, Ar, Cr, Mo, Ag, Xe and Pb) were implanted (with energies varying from 28 to 280 keV) in a 316LVM austenitic stainless steel. The implanted layer has a thickness limited to 80 nm and a maximum implanted element concentration lower than 10 % at. The analysis of the implanted layer by grazing incidence X ray diffraction highlights deformations of austenite lines, appearance of ferrite and amorphization of the layer. Ferritic phase which appears at the grain boundaries, whatever the implanted element, is formed above a given 'threshold' of energy (produced of fluency by the energy of an ion). The formation of ferrite as well as the amorphization of the implanted layer depends only on energy. In order to understand the deformations of austenite diffraction lines, a simulation model of these lines was elaborated. The model correctly describes the observed deformations (broadening, shift, splitting) with the assumption that the expansion of the austenitic lattice is due to the presence of implanted element and is proportional to the element concentration through a coefficient k'. This coefficient only depends on the element and varies linearly with its radius. (author)

Influence of localized deformation on A-286 austenitic stainless steel stress corrosion cracking in PWR primary water; Influence de la localisation de la deformation sur la corrosion sous contrainte de l'acier inoxydable austenitique A-286 en milieu primaire des REP

Energy Technology Data Exchange (ETDEWEB)

Savoie, M

2007-01-15

Irradiation-assisted stress corrosion cracking (IASCC) of austenitic stainless steels is known to be a critical issue for structural components of nuclear reactor cores. The deformation of irradiated austenitic stainless steels is extremely heterogeneous and localized in deformation bands that may play a significant role in IASCC. In this study, an original approach is proposed to determine the influence of localized deformation on austenitic stainless steels SCC in simulated PWR primary water. The approach consists in (i) performing low cycle fatigue tests on austenitic stainless steel A-286 strengthened by {gamma}' precipitates Ni{sub 3}(Ti,Al) in order to shear and dissolve the precipitates in intense slip bands, leading to a localization of the deformation within and in (ii) assessing the influence of these {gamma}'-free localized deformation bands on A-286 SCC by means of comparative CERT tests performed on specimens with similar yield strength, containing or not {gamma}'-free localized deformation bands. Results show that strain localization significantly promotes A-286 SCC in simulated PWR primary water at 320 and 360 C. Moreover, A-286 is a precipitation-hardening austenitic stainless steel used for applications in light water reactors. The second objective of this work is to gain insights into the influence of heat treatment and metallurgical structure on A-286 SCC susceptibility in PWR primary water. The results obtained demonstrate a strong correlation between yield strength and SCC susceptibility of A-286 in PWR primary water at 320 and 360 C. (author)

Propagation of thermal neutrons in mock-up screw-shaped steel elements with water protection; Propagation des neutrons thermiques dans des fausses cartouches d'acier en helice dans une protection d'eau. Programme tournesol 3

Energy Technology Data Exchange (ETDEWEB)

Devillers, C L; Lanore, J M [Commissariat a l' Energie Atomique, Fontenay-aux-Roses (France). Centre d' Etudes Nucleaires

1967-07-01

This report treats the streaming of thermal neutrons in a cylindrical duct in light water. The duct contains a spiral iron shield. Transmission and reflection matrices are used to describe the probabilities for the thermal neutrons to be absorbed or to be scattered on the surfaces. The neutron paths across the void are represented by geometrical matrices. The numerical resolution is performed by the Monte-Carlo method. (authors) [French] Dans ce rapport on traite un probleme de fuites de neutrons thermiques dans un canal cylindrique plonge dans l'eau et obture par un ecran helicoidal en acier. On utilise des matrices de transmission-reflexion pour decrire les probabilites d'absorption et de diffusion des neutrons sur les parois et l'helicoide et des matrices de correspondance geometrique pour representer la propagation dans le vide. La resolution numerique se fait par une methode de Monte-Carlo. (auteur)

Prévision de l'épaisseur du film passif d'un acier inoxydable 316L soumis au fretting corrosion grâce au Point Defect Model, PDM Predicting the steady state thickness of passive films with the Point Defect Model in fretting corrosion experiments

Directory of Open Access Journals (Sweden)

Geringer Jean

2013-11-01

Full Text Available Les implants orthopédiques de hanche ont une durée de vie d'environ 15 ans. Par exemple, la tige fémorale d'un tel implant peut être réalisée en acier inoxydable 316L ou 316LN. Le fretting corrosion, frottement sous petits déplacements, peut se produire pendant la marche humaine en raison des chargements répétés entre le métal de la prothèse et l'os. Plusieurs investigations expérimentales du fretting corrosion ont été entreprises. Cette couche passive de quelques nanomètres, à température ambiante, est le point clef sur lequel repose le développement de notre civilisation, selon certains auteurs. Ce travail vise à prédire les épaisseurs de cette couche passive de l'acier inoxydable soumis au fretting corrosion, avec une attention spécifique sur le rôle des protéines. Le modèle utilisé est basé sur le Point Defect Model, PDM (à une échelle microscopique et une amélioration de ce modèle en prenant en compte le processus de frottement sous petits débattements. L'algorithme génétique a été utilisé pour optimiser la convergence du problème. Les résultats les plus importants sont, comme démontré avec les essais expérimentaux, que l'albumine, la protéine étudiée, empêche les dégradations de l'acier inoxydable aux plus faibles concentrations d'ions chlorure ; ensuite, aux plus fortes concentrations de chlorures, un temps d'incubation est nécessaire pour détruire le film passif. Some implants have approximately a lifetime of 15 years. The femoral stem, for example, should be made of 316L/316LN stainless steel. Fretting corrosion, friction under small displacements, should occur during human gait, due to repeated loadings and un-loadings, between stainless steel and bone for instance. Some experimental investigations of fretting corrosion have been practiced. As well known, metallic alloys and especially stainless steels are covered with a passive film that prevents from the corrosion and degradation

Development of novel protective high temperature coatings on heat exchanger steels and their corrosion resistance in simulated coal firing environment

OpenAIRE

Rohr, Valentin

2005-01-01

Afin d'augmenter leur rendement, les centrales thermiques sont amenées à élever leur température de fonctionnement. Ceci nécessite une amélioration de la résistance à la corrosion des matériaux constitutifs des échangeurs de chaleur. Ainsi, l'objet de cette étude est de développer des revêtements anticorrosion à partir du procédé de cémentation activée. Deux types d'aciers pour échangeurs de chaleur ont été étudiés : un acier austénitique contenant 17% Cr et 13% Ni, et trois aciers ferrito-ma...

Formation mechanism of solute clusters under neutron irradiation in ferritic model alloys and in a reactor pressure vessel steel: clusters of defects; Mecanismes de fragilisation sous irradiation aux neutrons d'alliages modeles ferritiques et d'un acier de cuve: amas de defauts

Energy Technology Data Exchange (ETDEWEB)

Meslin-Chiffon, E

2007-11-15

The embrittlement of reactor pressure vessel (RPV) under irradiation is partly due to the formation of point defects (PD) and solute clusters. The aim of this work was to gain more insight into the formation mechanisms of solute clusters in low copper ([Cu] = 0.1 wt%) FeCu and FeCuMnNi model alloys, in a copper free FeMnNi model alloy and in a low copper French RPV steel (16MND5). These materials were neutron-irradiated around 300 C in a test reactor. Solute clusters were characterized by tomographic atom probe whereas PD clusters were simulated with a rate theory numerical code calibrated under cascade damage conditions using transmission electron microscopy analysis. The confrontation between experiments and simulation reveals that a heterogeneous irradiation-induced solute precipitation/segregation probably occurs on PD clusters. (author)

RPV-1: a first virtual reactor to simulate irradiation effects in light water reactor pressure vessel steels; RPV-1: un premier reacteur virtuel pour simuler les effets d'irradiation dans les aciers de cuve des reacteurs a eau legere

Energy Technology Data Exchange (ETDEWEB)

Jumel, St

2005-01-15

The presented work was aimed at building a first VTR (virtual test reactor) to simulate irradiation effects in pressure vessel steels of nuclear reactor. It mainly consisted in: - modeling the formation of the irradiation induced damage in such steels, as well as their plasticity behavior - selecting codes and models to carry out the simulations of the involved mechanisms. Since the main focus was to build a first tool (rather than a perfect tool), it was decided to use, as much as possible, existing codes and models in spite of their imperfections. - developing and parameterizing two missing codes: INCAS and DUPAIR. - proposing an architecture to link the selected codes and models. - constructing and validating the tool. RPV-1 is made of five codes and two databases which are linked up so as to receive, treat and/or transmit data. A user friendly Python interface facilitates the running of the simulations and the visualization of the results. RPV-1 relies on many simplifications and approximations and has to be considered as a prototype aimed at clearing the way. According to the functionalities targeted for RPV-1, the main weakness is a bad Ni and Mn sensitivity. However, the tool can already be used for many applications (understanding of experimental results, assessment of effects of material and irradiation conditions,....). (O.M.)

Effects of hydrogen on the tensile strength characteristics of stainless steels; Effets de l'hydrogene sur les caracteristiques de rupture par traction d'aciers inoxydables

Energy Technology Data Exchange (ETDEWEB)

Blanchard, R; Pelissier, J; Pluchery, M [Commissariat a l' Energie Atomique, Grenoble (France).Centre d' Etudes Nucleaires; Commissariat a l' Energie Atomique, Saclay (France).Centre d' Etudes Nucleaires

1961-07-01

This paper deals with the effects of hydrogen on stainless steel, that might possibly be used as a canning material in hydrogen-cooled reactors. Apparent ultimate-tensile strength is only 80 per cent of initial value for hydrogen content about 50 cc NTP/ 100 g, and reduction in area decreases from 80 to 55 per cent. A special two-stage replica technique has been developed which allows fracture surface of small tensile specimens (about 0.1 mm diam.) to be examined in an electron microscope. All the specimens showed evidence of ductile character throughout the range of hydrogen contents investigated, but the aspect of the fracture surfaces gradually changes with increasing amounts. (author) [French] On etudie les effets de l'hydrogene sur des aciers inoxydables, qui sont des materiaux de gainage possibles pour des reacteurs utilisant l'hydrogene comme gaz de refroidissement. On montre que la charge apparente de rupture a la traction n'est plus que 80 pour cent de sa valeur initiale lorsque la teneur en hydrogene atteint 50 cc TPN/ 100 g, et que la striction passe dans ces conditions de 80 a 55 pour cent. L'examen microfractographique qui a ete effectue avec succes par une technique de double replique malgre la petitesse des echantillons (0,3 mm de diametre environ), revele que tout en gardant un caractere ductile, l'aspect des surfaces de rupture evolue notablement avec la teneur en hydrogene. (auteur)

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African Journals Online (AJOL)

Vol 32 (2016), Comportement à l'usure des forets hélicoïdaux en acier rapide lors du perçage de l' acier C18, Abstract PDF. Nacer Mokas, Lakhdar Boulanouar. Vol 24 (2015), Comportement d'un béton à hautes performances à base de laitier en milieu sulfatique, Abstract PDF. R Chaid, A Bali, R Jauberthie, A Talah.

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African Journals Online (AJOL)

Boulanouar, Lakhdar. Vol 32 (2016) - Articles Comportement à l'usure des forets hélicoïdaux en acier rapide lors du perçage de l' acier C18 Abstract PDF. ISSN: 2352-9717. AJOL African Journals Online. HOW TO USE AJOL... for Researchers · for Librarians · for Authors · FAQ's · More about AJOL · AJOL's Partners · Terms ...

Study of stress relief cracking in titanium stabilized austenitic stainless steel; Etude de la fissuration differee par relaxation d'un acier inoxydable austenitique stabilise au titane

Energy Technology Data Exchange (ETDEWEB)

Chabaud-Reytier, M

1999-07-01

The heat affected zone (HAZ) of titanium stabilised austenitic stainless steel welds (AISI 321) may exhibit a serious form of intercrystalline cracking during service at high temperature. This type of cracking, called 'stress relief cracking', is known to be due to work hardening but also to ageing: a fine and abundant intragranular Ti(C,N) precipitation appears near the fusion line and modifies the mechanical behaviour of the HAZ. This study aims to better know the accused mechanism and to succeed in estimating the risk of such cracking in welded junctions of 321 stainless steel. To analyse this embrittlement mechanism, and to assess the lifetime of real components, different HAZ are simulated by heat treatments applied to the base material which is submitted to various cold rolling and ageing conditions in order to reproduce the HAZ microstructure. Then, we study the effects of work hardening and ageing on the titanium carbide precipitation, on the mechanical (tensile and creep) behaviour of the resulting material and on its stress relief cracking sensitivity. It is shown that work hardening is the main parameter of the mechanism and that ageing do not favour crack initiation although it leads to titanium carbide precipitation. The role of this precipitation is also discussed. Moreover, a creep damage model is identified by a local approach to fracture. Materials sensitive to stress relief cracking are selected. Then, creep tests are carried out on notched bars in order to quantify the intergranular damage of these different materials; afterwards, these measurements are combined with calculated mechanical fields. Finally, it is shown that the model gives good results to assess crack initiation for a compact tension (CT) specimen during relaxation tests, as well as for a notched tubular specimen tested at 600 deg. C under a steady torque. (author)

Detection of irradiated spice in blend of irradiated and un-irradiated spices using thermoluminescence method

International Nuclear Information System (INIS)

Goto, Michiko; Yamazaki, Masao; Sekiguchi, Masayuki; Todoriki, Setsuko; Miyahara, Makoto

2007-01-01

Five blended spice sample were prepared by mixing irradiated and un-irradiated black pepper and paprika at different ratios. Blended black pepper containing 2%(w/w) of 5.4 kGy-irradiated black pepper showed no maximum at glow1. Irradiated black pepper samples, mixed to 5 or 10%(w/w), were identified as 'irradiated' or 'partially irradiated' or 'un-irradiated'. All samples with un-irradiated pepper up to 20%(w/w) were identified as irradiated'. In the case 5.0 kGy-irradiated paprika were mixed with un-irradiated paprika up to 5%(w/w), all samples were identified as irradiated'. The glow1 curves of samples, including irradiated paprika at 0.2%(w/w) or higher, exhibited a maximum between 150 and 250degC. The results suggest the existence of different critical mixing ratio for the detection of irradiation among each spices. Temperature range for integration of the TL glow intensity were compared between 70-400degC and approximate 150-250degC, and revealed that the latter temperature range was determined based on the measurement of TLD100. Although TL glow ratio in 150-250degC was lower than that of 70-400degC range, identification of irradiation was not affected. Treatment of un-irradiated black pepper and paprika with ultraviolet rays had no effect on the detection of irradiation. (author)

Results of the irradiation of mixed UO{sub 2} - PuO{sub 2} oxide fuel elements; Resultats d'irradiation d'elements combustibles en oxyde mixte UO{sub 2} - PuO{sub 2}

Energy Technology Data Exchange (ETDEWEB)

Mikailoff, H; Mustelier, J P; Bloch, J; Ezran, L; Hayet, L [Commissariat a l' Energie Atomique, Fontenay-aux-Roses (France). Centre d' Etudes Nucleaires

1966-07-01

In order to study the behaviour of fuel elements used for the first charge of the reactor Rapsodie, a first batch of eleven needles was irradiated in the reactor EL3 and then examined. These needles (having a shape very similar lo that of the actual needles to be used) were made up of a stack of sintered mixed-oxide pellets: UO{sub 2} containing about 10 per cent of PuO{sub 2}. The density was 85 to 97 per cent of the theoretical, value. The diametral gap between the oxide and the stainless steel can was between 0,06 and 0,27 mm. The specific powers varied from 1230 to 2700 W/cm{sup 3} and the can temperature was between 450 and 630 C. The maximum burn-up attained was 22000 MW days/tonne. Examination of the needles (metrology, radiography and {gamma}-spectrography) revealed certain macroscopic changes, and the evolution of the fuel was shown by micrographic studies. These observations were used, together with flux measurements results, to calculate the temperature distribution inside the fuel. The volume of the fission gas produced was measured in some of the samples; the results are interpreted taking into account the temperature distribution in the oxide and the burn-up attained. Finally a study was made both of the behaviour of a fuel element whose central part was molten during irradiation, and of the effect of sodium which had penetrated into some of the samples following can rupture. (author) [French] Afin d'etudier le comportement des elements combustibles destines a la premiere charge du reacteur Rapsodie, une premiere serie de onze aiguilles a ete irradiee dans le reacteur EL3 et examinee apres irradiation. Ces aiguilles (aux caracteristiques geometriques tres proches de celles des aiguilles definitives) etaient constituees d'un empilement de pastilles frittees en oxyde mixte UO{sub 2} a 10 pour cent environ de PuO{sub 2}, dont la densite etait comprise entre 85 et 97 pour cent de la densite theorique. Le jeu diametral entre l'oxyde et la gaine en acier

Irradiation probe and laboratory for irradiated material evaluation

International Nuclear Information System (INIS)

Smutny, S.; Kupca, L.; Beno, P.; Stubna, M.; Mrva, V.; Chmelo, P.

1975-09-01

The survey and assessment are given of the tasks carried out in the years 1971 to 1975 within the development of methods for structural materials irradiation and of a probe for the irradiation thereof in the A-1 reactor. The programme and implementation of laboratory tests of the irradiation probe are described. In the actual reactor irradiation, the pulse tube length between the pressure governor and the irradiation probe is approximately 20 m, the diameter is 2.2 mm. Temperature reaches 800 degC while the pressure control system operates at 20 degC. The laboratory tests (carried out at 20 degC) showed that the response time of the pressure control system to a stepwise pressure change in the irradiation probe from 0 to 22 at. is 0.5 s. Pressure changes were also studied in the irradiation probe and in the entire system resulting from temperature changes in the irradiation probe. Temperature distribution in the body of the irradiation probe heating furnace was determined. (B.S.)

Chapter 2: Irradiators

Energy Technology Data Exchange (ETDEWEB)

NONE

2018-04-01

The chapter 2 presents the subjects: 1) gamma irradiators which includes: Category-I gamma irradiators (self-contained); Category-II gamma irradiators (panoramic and dry storage); Category-III gamma irradiators (self-contained in water); Category-IV gamma irradiators (panoramic and wet storage); source rack for Category-IV gamma irradiators; product transport system for Category-IV gamma irradiators; radiation shield for gamma irradiators; 2) accelerators which includes: Category-I Accelerators (shielded irradiator); Category-II Accelerators (irradiator inside a shielded room); Irradiation application examples.

Food irradiation

International Nuclear Information System (INIS)

Sato, Tomotaro; Aoki, Shohei

1976-01-01

Definition and significance of food irradiation were described. The details of its development and present state were also described. The effect of the irradiation on Irish potatoes, onions, wiener sausages, kamaboko (boiled fish-paste), and mandarin oranges was evaluated; and healthiness of food irradiation was discussed. Studies of the irradiation equipment for Irish potatoes in a large-sized container, and the silo-typed irradiation equipment for rice and wheat were mentioned. Shihoro RI center in Hokkaido which was put to practical use for the irradiation of Irish potatoes was introduced. The state of permission of food irradiation in foreign countries in 1975 was introduced. As a view of the food irradiation in the future, its utilization for the prevention of epidemics due to imported foods was mentioned. (Serizawa, K.)

Food irradiation

Energy Technology Data Exchange (ETDEWEB)

Gruenewald, T

1985-01-01

Food irradiation has become a matter of topical interest also in the Federal Republic of Germany following applications for exemptions concerning irradiation tests of spices. After risks to human health by irradiation doses up to a level sufficient for product pasteurization were excluded, irradiation now offers a method suitable primarily for the disinfestation of fruit and decontamination of frozen and dried food. Codex Alimentarius standards which refer also to supervision and dosimetry have been established; they should be adopted as national law. However, in the majority of cases where individual countries including EC member-countries so far permitted food irradiation, these standards were not yet used. Approved irradiation technique for industrial use is available. Several industrial food irradiation plants, partly working also on a contractual basis, are already in operation in various countries. Consumer response still is largely unknown; since irradiated food is labelled, consumption of irradiated food will be decided upon by consumers.

Results of the irradiation of mixed UO{sub 2} - PuO{sub 2} oxide fuel elements; Resultats d'irradiation d'elements combustibles en oxyde mixte UO{sub 2} - PuO{sub 2}

Energy Technology Data Exchange (ETDEWEB)

Mikailoff, H.; Mustelier, J.P.; Bloch, J.; Ezran, L.; Hayet, L. [Commissariat a l' Energie Atomique, Fontenay-aux-Roses (France). Centre d' Etudes Nucleaires

1966-07-01

gaine en acier inoxydable etait compris entre 0,06 et 0,27 mm. Les puissances specifiques ont varie de 1230 a 2700 W/cm{sup 3} et la temperature de la gaine etait situee entre 450 et 630 C, Le taux de combustion maximal atteint a ete de 22000 MWj/t. L'examen des aiguilles (metrologie, radiographie et spectrographie {gamma}) a revele certaines modifications macroscopiques, et l'evolution du combustible a ete mise en evidence par la micrographie. On a utilise ces observations, avec les resultats des mesures de flux, pour calculer la repartition des temperatures a l'interieur du combustible. Le volume des gaz de fission degages a ete mesure dans certaines aiguilles: les resultats sont interpretes en liaison avec la repartition des temperatures dans l'oxyde et le taux de combustion atteint. Enfin on a examine d'une part, le comportement d'un element combustible dont la partie centrale etait fondue pendant l'irradiation, et d'autre part, l'action du sodium entre dans certaines aiguilles dont la gaine s'etait rompue. (auteur)

Food irradiation

International Nuclear Information System (INIS)

Lindqvist, H.

1996-01-01

This paper is a review of food irradiation and lists plants for food irradiation in the world. Possible applications for irradiation are discussed, and changes induced in food from radiation, nutritional as well as organoleptic, are reviewed. Possible toxicological risks with irradiated food and risks from alternative methods for treatment are also brought up. Ways to analyze weather food has been irradiated or not are presented. 8 refs

Irradiation proctitis

International Nuclear Information System (INIS)

Minami, Akira

1977-01-01

Literatures on late rectal injuries are discussed, referring to two patients with uterine cervical cancer in whom irradiation proctitis occurred after telecobalt irradiation following uterine extirpation. To one patients, a total of 5000 rads was irradiated, dividing into 250 rads at one time, and after 3 months, irradiation with a total of 2000 rads, dividing into 200 rads at one time, was further given. In another one patient, two parallel opposing portal irradiation with a total of 6000 rads was given. About a year after the irradiation, rectal injuries and cystitis, accompanying with hemorrhage, were found in both of the patients. Rectal amputation and proctotoreusis were performed. Cystitis was treated by cystic irradiation in the urological department. Pathohistological studies of the rectal specimen revealed atrophic mucosa, and dilatation of the blood vessels and edema in the colonic submucosa. Incidence of this disease, term when the disease occurs, irradiation dose, type of the disease, treatment and prevention are described on the basis of the literatures. (Kanao, N.)

Irradiation proctitis

Energy Technology Data Exchange (ETDEWEB)

Minami, A [Osaka Kita Tsishin Hospital (Japan)

1977-06-01

Literatures on late rectal injuries are discussed, referring to two patients with uterine cervical cancer in whom irradiation proctitis occurred after telecobalt irradiation following uterine extirpation. To one patients, a total of 5000 rads was irradiated, dividing into 250 rads at one time, and after 3 months, irradiation with a total of 2000 rads, dividing into 200 rads at one time, was further given. In another one patient, two parallel opposing portal irradiation with a total of 6000 rads was given. About a year after the irradiation, rectal injuries and cystitis, accompanying with hemorrhage, were found in both of the patients. Rectal amputation and proctotoreusis were performed. Cystitis was treated by cystic irradiation in the urological department. Pathohistological studies of the rectal specimen revealed atrophic mucosa, and dilatation of the blood vessels and edema in the colonic submucosa. Incidence of this disease, term when the disease occurs, irradiation dose, type of the disease, treatment and prevention are described on the basis of the literatures.

Diffusion welding; Soudage par diffusion

Energy Technology Data Exchange (ETDEWEB)

Daniault, J; Gillet, R [Commissariat a l' Energie Atomique, Grenoble (France). Centre d' Etudes Nucleaires

1969-07-01

After a brief recall of the principle, and of the advantages of the method, we give some examples of metallic bonding in a first part where we describe preliminary trials: Ta-Mo, Zr-Zr, Zr-Nb, Nb-stainless steel, Mo-stainless steel, aluminium-aluminium (A5-A5). The second part of the note is devoted to trials on construction elements: on tubular elements for bonding between Mo or Nb on one hand, and stainless steel on the other hand (We indicate in what conditions the bonding are tight and what are their mechanical strength and their resistance to thermic cycles). We indicate, in this chapter, a method to obtain radiation windows in Be welded on an element made of stainless steel. (authors) [French] pres un bref rappel du principe, et des avantages de la methode, on donne quelques exemples de liaisons metalliques dans une premiere partie qui traite d'essais preliminaires: Ta - Mo, Zr - Zr, Zr - Nb, Nb - acier inoxydable, molybdene - acier inoxydable, aluminium - aluminium (A5-A5). La deuxieme partie de la note est consacree a des essais sur elements de construction: sur des elements tabulaires, pour des liaisons entre molybdene ou niobium d'une part, et acier inoxydable d'autre part. On indique dans quelles conditions les liaisons sont etanches et quelles sont leurs resistances mecaniques et aux chocs thermiques. On indique, dans ce meme chapitre, une methode pour l'obtention de fenetres en beryllium soudees sur un support en acier inoxydable. (auteurs)

Food irradiation

International Nuclear Information System (INIS)

Soothill, R.

1987-01-01

The issue of food irradiation has become important in Australia and overseas. This article discusses the results of the Australian Consumers' Association's (ACA) Inquiry into food irradiation, commissioned by the Federal Government. Issues discussed include: what is food irradiation; why irradiate food; how much food is consumer rights; and national regulations

Evaluation of irradiation hardening of proton irradiated stainless steels by nanoindentation

International Nuclear Information System (INIS)

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

2014-01-01

Ion irradiation experiments are useful for investigating irradiation damage. However, estimating the irradiation hardening of ion-irradiated materials is challenging because of the shallow damage induced region. Therefore, the purpose of this study is to prove usefulness of nanoindentation technique for estimation of irradiation hardening for ion-irradiated materials. SUS316L austenitic stainless steel was used and it was irradiated by 1 MeV H + ions to a nominal displacement damage of 0.1, 0.3, 1, and 8 dpa at 573 K. The irradiation hardness of the irradiated specimens were measured and analyzed by Nix–Gao model. The indentation size effect was observed in both unirradiated and irradiated specimens. The hardness of the irradiated specimens changed significantly at certain indentation depths. The depth at which the hardness varied indicated that the region deformed by the indenter had reached the boundary between the irradiated and unirradiated regions. The hardness of the irradiated region was proportional to the inverse of the indentation depth in the Nix–Gao plot. The bulk hardness of the irradiated region, H 0 , estimated by the Nix–Gao plot and Vickers hardness were found to be related to each other, and the relationship could be described by the equation, HV = 0.76H 0 . Thus, the nanoindentation technique demonstrated in this study is valuable for measuring irradiation hardening in ion-irradiated materials

Post irradiation test report of irradiated DUPIC simulated fuel

International Nuclear Information System (INIS)

Yang, Myung Seung; Jung, I. H.; Moon, J. S. and others

2001-12-01

The post-irradiation examination of irradiated DUPIC (Direct Use of Spent PWR Fuel in CANDU Reactors) simulated fuel in HANARO was performed at IMEF (Irradiated Material Examination Facility) in KAERI during 6 months from October 1999 to March 2000. The objectives of this post-irradiation test are i) the integrity of the capsule to be used for DUPIC fuel, ii) ensuring the irradiation requirements of DUPIC fuel at HANARO, iii) performance verification in-core behavior at HANARO of DUPIC simulated fuel, iv) establishing and improvement the data base for DUPIC fuel performance verification codes, and v) establishing the irradiation procedure in HANARO for DUPIC fuel. The post-irradiation examination performed are γ-scanning, profilometry, density, hardness, observation the microstructure and fission product distribution by optical microscope and electron probe microanalyser (EPMA)

Facts about food irradiation: Irradiated foods and the consumer

International Nuclear Information System (INIS)

1991-01-01

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 shown no reluctance to buy irradiated food products. 4 refs

Food irradiation

International Nuclear Information System (INIS)

Matsuyama, Akira

1990-01-01

This paper reviews researches, commentaries, and conference and public records of food irradiation, published mainly during the period 1987-1989, focusing on the current conditions of food irradiation that may pose not only scientific or technologic problems but also political issues or consumerism. Approximately 50 kinds of food, although not enough to fill economic benefit, are now permitted for food irradiation in the world. Consumerism is pointed out as the major factor that precludes the feasibility of food irradiation in the world. In the United States, irradiation is feasible only for spices. Food irradiation has already been feasible in France, Hollands, Belgium, and the Soviet Union; has under consideration in the Great Britain, and has been rejected in the West Germany. Although the feasibility of food irradiation is projected to increase gradually in the future, commercial success or failure depends on the final selection of consumers. In this respect, the role of education and public information are stressed. Meat radicidation and recent progress in the method for detecting irradiated food are referred to. (N.K.) 128 refs

Gamma Irradiation does not Cause Carcinogenesis of Irradiated Herbs

International Nuclear Information System (INIS)

Thongphasuk, Jarunee; Thongphasuk, Piyanuch; Eamsiri, Jarurut; Pongpat, Suchada

2009-07-01

Full text: Microbial contamination of medicinal herbs can be effectively reduced by gamma irradiation. Since irradiation may cause carcinogenicity of the irradiated herbs, the objective of this research is to study the effect of gamma irradiation (10 and 25 kGy) from cobalt-60 on carcinogenicity. The herbs studied were Pueraria candollei Grah., Curcuma longa Linn. Zingiber montanum, Senna alexandrina P. Miller, Eurycoma Longifolia Jack, Gymnostema pentaphylum Makino, Ginkgo biloba, Houttuynia cordata T., Andrographis paniculata, Thunbergia laurifolia L., Garcinia atroviridis G., and Cinnamomum verum J.S.Presl. The results showed that gamma irradiation at the dose of 10 and 25 kGy did not cause carcinogenicity of the irradiated herbs

Food irradiation

International Nuclear Information System (INIS)

Duchacek, V.

1989-01-01

The ranges of doses used for food irradiation and their effect on the processed foods are outlined. The wholesomeness of irradiated foods is discussed. The present food irradiation technology development in the world is described. A review of the irradiated foods permitted for public consumption, the purposes of food irradiaton, the doses used and a review of the commercial-scale food irradiators are tabulated. The history and the present state of food processing in Czechoslovakia are described. (author). 1 fig., 3 tabs., 13 refs

Irradiated foods

International Nuclear Information System (INIS)

Darrington, Hugh

1988-06-01

This special edition of 'Food Manufacture' presents papers on the following aspects of the use of irradiation in the food industry:- 1) an outline view of current technology and its potential. 2) Safety and wholesomeness of irradiated and non-irradiated foods. 3) A review of the known effects of irradiation on packaging. 4) The problems of regulating the use of irradiation and consumer protection against abuse. 5) The detection problem - current procedures. 6) Description of the Gammaster BV plant in Holland. 7) World outline review. 8) Current and future commercial activities in Europe. (U.K.)

Study of a design criterion for 316L irradiated represented by a strain hardened material; Etude d'un critere de dimensionnement d'un acier 316L irradie represente par un materiau ecroui

Energy Technology Data Exchange (ETDEWEB)

Gouin, H

1999-07-01

The aim of this study is to analyse the consequence of radiation on different structure submitted to imposed displacement loading and for damages due to plastic instability or rupture. The main consequence of radiation is a material hardening with a ductility decrease. This effect is similar to initial mechanical hardening: the mechanical properties (determined on smooth tensile specimen) evolve in the same way while irradiation or mechanical hardening increase. So in this study, radiation hardening is simulated by mechanical hardening (swaging). Tests were carried out for which two damages were considered: plastic instability and rupture. These two damages were studied with initial mechanical hardening (5 tested hammering rate 0, 15, 25, 35 and 45% on 316L stainless steel). Likewise two types of loading were studied: tensile or bending loading on specimens with or without geometrical singularities (notches). From tensile tests, two deformation criteria are proposed for prevention against the two quoted damages. Numerical study is carried out allowing to confirm hypothesis made at the time of the tensile test result interpretation and to validate the rupture criterion by applying on bending test. (author)

Storage tests with irradiated and non-irradiated onions

International Nuclear Information System (INIS)

Gruenewald, T.; Rumpf, G.; Troemel, I.; Bundesforschungsanstalt fuer Ernaehrung, Karlsruhe

1978-07-01

The results of several test series on the storage of irradiated and non-irradiated German grown onion are reported. Investigated was the influence of the irradiation conditions such as time and dose and of the storage conditions on sprouting, spoilage, browning of the vegetation centres, composition of the onions, strength and sensorial properties of seven different onion varieties. If the onions were irradiated during the dormancy period following harvest, a dose of 50 Gy (krad) was sufficient to prevent sprouting. Regarding the irradiated onions, it was not possible by variation of the storage conditions within the limits set by practical requirements to extend the dormancy period or to prevent browning of the vegetation centres, however. (orig.) 891 MG 892 RSW [de

Food irradiation

International Nuclear Information System (INIS)

Anon.

1985-01-01

The article explains what radiation does to food to preserve it. Food irradiation is of economic importance to Canada because Atomic Energy of Canada Limited is the leading world supplier of industrial irradiators. Progress is being made towards changing regulations which have restricted the irradiation of food in the United States and Canada. Examples are given of applications in other countries. Opposition to food irradiation by antinuclear groups is addressed

Mechanical and irradiation properties of zirconium alloys irradiated in HANARO

International Nuclear Information System (INIS)

Kwon, Oh Hyun; Eom, Kyong Bo; Kim, Jae Ik; Suh, Jung Min; Jeon, Kyeong Lak

2011-01-01

These experimental studies are carried out to build a database for analyzing fuel performance in nuclear power plants. In particular, this study focuses on the mechanical and irradiation properties of three kinds of zirconium alloy (Alloy A, Alloy B and Alloy C) irradiated in the HANARO (High-flux Advanced Neutron Application Reactor), one of the leading multipurpose research reactors in the world. Yield strength and ultimate tensile strength were measured to determine the mechanical properties before and after irradiation, while irradiation growth was measured for the irradiation properties. The samples for irradiation testing are classified by texture. For the irradiation condition, all samples were wrapped into the capsule (07M-13N) and irradiated in the HANARO for about 100 days (E > 1.0 MeV, 1.1 10 21 n/cm 2 ). These tests and results indicate that the mechanical properties of zirconium alloys are similar whether unirradiated or irradiated. Alloy B has shown the highest yield strength and tensile strength properties compared to other alloys in irradiated condition. Even though each of the zirconium alloys has a different alloying content, this content does not seem to affect the mechanical properties under an unirradiated condition and low fluence. And all the alloys have shown the tendency to increase in yield strength and ultimate tensile strength. Transverse specimens of each of the zirconium alloys have a slightly lower irradiation growth tendency than longitudinal specimens. However, for clear analysis of texture effects, further testing under higher irradiation conditions is needed

Characterization of Irradiated and Non-Irradiated Rubber from Automotive Scrap Tires

Science.gov (United States)

Souza, Clécia Moura; Silva, Leonardo G.

The aim of this work was to characterize the samples of irradiated and non-irradiated rubber from automotive scrap tires. Rubber samples from scrap tires were irradiated at irradiation doses of 200, 400 and 600kGy in an electron beam accelerator. Subsequently, both the irradiated and non-irradiated samples were characterized by thermogravimetry (TG), differential scanning calorimetry (DSC), tensile strength mechanical test, and Fourier transform infrared (FTIR) spectrophotometry.

Consumer opinions in Argentina on food irradiation: irradiated onions

International Nuclear Information System (INIS)

Curzio, O.A.; Croci, C.A.

1998-01-01

Two surveys were carried out in Buenos Aires of consumer attitudes towards irradiated onions [no data given]. The first investigated the general level of consumer knowledge concerning food irradiation, whilst the second (which covered consumers who had actually bought irradiated onions) examined reasons for purchase and consumer satisfaction. Results reveal that more than 90% of consumers surveyed had a very limited knowledge of food irradiation

Reheat cracking of austenitic stainless steels - pre-strain effect on intergranular damage; Fissuration en relaxation des aciers inoxydables austenitiques - influence de l'ecrouissage sur l'endommagement intergranulaire

Energy Technology Data Exchange (ETDEWEB)

Auzoux, Q

2004-01-01

Welding process induces strain in 316 stainless steel affected zones. Their microstructure was reproduce by rolling of three different steels (316L, 316L(N) et 316H). Traction, creep and relaxation tests were performed at 550 deg C and 600 deg C on smooth, notched and pre-cracked specimens. Pre-strain by rolling increases the hardness and the creep resistance because of the high dislocation density but decreases ductility because of the fast development of intergranular damage. This embrittlement leads to crack propagation during relaxation tests on pre-strained steels without distinction in respect to their carbon or nitrogen content. A new intergranular damage model was built using local micro-cracks measurements and finite elements analysis. Pre-strain effect and stress triaxiality ratio effect are reproduced by the modelling so that the reheat cracking risk near welds can now be estimated. (author)

Facts about food irradiation: Chemical changes in irradiated foods

International Nuclear Information System (INIS)

1991-01-01

This fact sheet addresses the safety of irradiated food. The irradiation process produces very little chemical change in food, and laboratory experiments have shown no harmful effects in animals fed with irradiated milk powder. 3 refs

Radiation Effect on Secondary Cancerization by Tumour Cell Grafts. Take of Irradiated Tumour Cells in Irradiated and Non-Irradiated Animals

Energy Technology Data Exchange (ETDEWEB)

Costachel, O.; Sandru, Gh.; Kitzulescu, I. [Oncological Institute, Bucharest (Romania)

1969-11-15

This study was designed to determine the ability of haemocytoblastoma, SME and Jensen tumours, which had been irradiated in vitro, to take in C{sub 57}BL/6 mice or Wistar rats that were whole-body irradiated at 0.4 kR and 0.6 kR respectively. It was found-that the take of tumour cell grafts irradiated in vitro increased in whole-body irradiated mice and rats but not in non-irradiated ones. When Wistar rats, that had been whole-body irradiated with 0.7 and 0.8 kR 1 - 7 months earlier and survived after treatment, were grafted with Jensen tumour cells irradiated in vitro with 3 kR they were found to develop tumours and lung metastases (in contrast to non-irradiated rats). A cross resistance against non-irradiated Jensen tumour cells was obtained in non- irradiated Wistar rats by grafting irradiated Jensen tumour cells. Chromosomal analysis showed two supplementary giant markers in the Jensen tumour cells that had been irradiated in vitro before grafting. (author)

Food irradiation

International Nuclear Information System (INIS)

Beyers, M.

1977-01-01

The objectives of food irradiation are outlined. The interaction of irradiation with matter is then discussed with special reference to the major constituents of foods. The application of chemical analysis in the evaluation of the wholesomeness of irradiated foods is summarized [af

Oxidation of iron and steels by carbon dioxide under pressure (1962); Oxydation du fer et des aciers par l'anhydride carbonique sous pression (1962)

Energy Technology Data Exchange (ETDEWEB)

Colombie, M [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

1962-07-01

After having developed one of the first thermo-balances to operate under pressure, we have studied the influence of the pressure on the corrosion of iron and steels by carbon dioxide. The corrosion was followed by three different methods simultaneously: by the oxidation kinetics, by micrographs, and by radiocrystallography. We have been able to show that the influence of the pressure is not negligible and we have provided much experimental evidence: oxidation kinetics, micrographic aspects, surface precipitation of carbon, metal carburization, the texture of the magnetite layer. All these phenomena are certainly modified by changes in the carbon dioxide pressure. In order to interpret most of our results we have been led to believe that the phenomenon of corrosion by CO{sub 2} depends on secondary reactions localised at the oxide-gas interface. This would constitute a major difference between the oxidation by CO{sub 2} and that by oxygen. (author) [French] Apres avoir etudie et mis au point une des premieres thermobalances fonctionnant sous pression, nous avons etudie l'influence de la pression sur la corrosion du fer et des aciers par l'anhydride carbonique. Notre etude a ete conduite simultanement sur trois plans differents: etude des cinetiques d'oxydation, etude micrographique et etude radiocristallographique. Nous avons pu montrer que l'influence de la pression n'etait pas negligeable et nous en avons fourni un faisceau de preuves experimentales important: cinetiques d'oxydation, aspect micrographique, precipitation superficielle de carbone, carburation du metal, texture de la couche de magnetite. Tous ces phenomenes sont sans aucun doute modifies par une variation de pression du gaz carbonique. Pour interpreter la plupart de nos resultats, nous avons ete conduits a penser que le phenomene de corrosion par CO{sub 2} etait tributaire de reactions secondaires localisees a l'interface oxyde-gaz. Ce serait la une des differences fondamentales entre l'oxydation par

Food irradiation

International Nuclear Information System (INIS)

Macklin, M.

1987-01-01

The Queensland Government has given its support the establishment of a food irradiation plant in Queensland. The decision to press ahead with a food irradiation plant is astonishing given that there are two independent inquiries being carried out into food irradiation - a Parliamentary Committee inquiry and an inquiry by the Australian Consumers Association, both of which have still to table their Reports. It is fair to assume from the Queensland Government's response to date, therefore, that the Government will proceed with its food irradiation proposals regardless of the outcomes of the various federal inquiries. The reasons for the Australian Democrats' opposition to food irradiation which are also those of concerned citizens are outlined

Rapid differentiation between gamma-irradiated and non irradiated potato tubers

International Nuclear Information System (INIS)

Jona, R.; Fronda, A.

1990-01-01

The use of gamma irradiation as commercial method for the preservation of fruits and vegetables calls for methods of differentiation between irradiated and non-irradiated foodstuffs. In a previous research, the polysaccharidic content of cell walls of irradiated tissue has been investigated, but it required rather long time to reach the result. A method devised to ascertain the vitality of cells has been applied to distinguish irradiated from non-irradiated potato tubers. 500 mg of tissue excised from tubers have been infiltrated with tetrazolium chloride 0.6% in phosphate buffer, pH 7.4. After 15 hrs of incubation at 30 0 C the treated tissues have been extracted with 95% ethanol whose O.D. has been measured at 530 mμ wavelength. The colour intensity of the alcohol allowed a very clearcut recognition of the irradiated tubers. (author)

Gamma irradiator

International Nuclear Information System (INIS)

Simonet, G.

1986-09-01

Fiability of devices set around reactors depends on material resistance under irradiation noticeably joints, insulators, which belongs to composition of technical, safety or physical incasurement devices. The irradiated fuel elements, during their desactivation in a pool, are an interesting gamma irradiation device to simulate damages created in a nuclear environment. The existing facility at Osiris allows to generate an homogeneous rate dose in an important volume. The control of the element distances to irradiation box allows to control this dose rate [fr

Foodstuff irradiation

International Nuclear Information System (INIS)

1982-01-01

Report written on behalf of the Danish Food Institute summarizes national and international rules and developments within food irradiation technology, chemical changes in irradiated foodstuffs, microbiological and health-related aspects of irradiation and finally technological prospects of this conservation form. Food irradiatin has not been hitherto applied in Denmark. Radiation sources and secondary radiation doses in processed food are characterized. Chemical changes due to irradiation are compared to those due to p.ex. food heating. Toxicological and microbiological tests and their results give no unequivocal answer to the problem whether a foodstuff has been irradiated. The most likely application fields in Denmark are for low radiation dosis inhibition of germination, riping delay and insecticide. Medium dosis (1-10 kGy) can reduce bacteria number while high dosis (10-50 kGy) will enable total elimination of microorganisms and viruses. Food irradiation can be acceptable as technological possibility with reservation, that further studies follow. (EG)

Estimation of irradiation temperature within the irradiation program Rheinsberg

CERN Document Server

Stephan, I; Prokert, F; Scholz, A

2003-01-01

The temperature monitoring within the irradiation programme Rheinsberg II was performed by diamond powder monitors. The method bases on the effect of temperature on the irradiation-induced increase of the diamond lattice constant. The method is described by a Russian code. In order to determine the irradiation temperature, the lattice constant is measured by means of a X-ray diffractometer after irradiation and subsequent isochronic annealing. The kink of the linearized temperature-lattice constant curves provides a value for the irradiation temperature. It has to be corrected according to the local neutron flux. The results of the lattice constant measurements show strong scatter. Furthermore there is a systematic error. The results of temperature monitoring by diamond powder are not satisfying. The most probable value lays within 255 C and 265 C and is near the value estimated from the thermal condition of the irradiation experiments.

Austin: austenitic steel irradiation E 145-02 Irradiation Report

International Nuclear Information System (INIS)

Genet, F.; Konrad, J.

1987-01-01

Safety measures for nuclear reactors require that the energy which might be liberated in a reactor core during an accident should be contained within the reactor pressure vessel, even after very long irradiation periods. Hence the need to know the mechanical properties at high deformation velocity of structure materials that have received irradiation damage due to their utilization. The stainless steels used in the structures of reactors undergo damage by both thermal and fast neutrons, causing important changes in the mechanical properties of these materials. Various austenitic steels available as structural materials were irradiated or are under irradiation in various reactors in order to study the evolution of the mechanical properties at high deformation velocity as a function of the irradiation damage rate. The experiment called AUSTIN (AUstenitic STeel IrradiatioN) 02 was performed by the JRC Petten Establishment on behalf of Ispra in support of the reactor safety programme

Irradiation of goods

International Nuclear Information System (INIS)

Huebner, G.

1992-01-01

The necessary dose and the dosage limits to be observed depend on the kind of product and the purpose of irradiation. Product density and density distribution, product dimensions, but also packaging, transport and storage conditions are specific parameters influencing the conditions of irradiation. The kind of irradiation plant - electron accelerator or gamma plant - , its capacity, transport system and geometric arrangement of the radiation field are factors influencing the irradiation conditions as well. This is exemplified by the irradiation of 3 different products, onions, deep-frozen chicken and high-protein feed. Feasibilities and limits of the irradiation technology are demonstrated. (orig.) [de

Comparison of deuterium retention for ion-irradiated and neutron-irradiated tungsten

International Nuclear Information System (INIS)

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

2014-01-01

The behavior of D retentions for Fe 2+ irradiated tungsten with the damage of 0.025-3 dpa was compared with that for neutron irradiated tungsten with 0.025 dpa. The D 2 TDS spectra for Fe 2+ irradiated tungsten consisted of two desorption stages at 450 K and 550 K although that for neutron irradiated tungsten was composed of three stages and addition desorption stage was found around 750 K. The desorption rate of major desorption stage at 550 K increased as the number of dpa by Fe 2+ irradiation increased. In addition, the first desorption stage at 450 K was only found for the damaged samples, indicating that the second stage would be based on intrinsic defects or vacancy produced by Fe 2+ irradiation and the first stage should be the accumulation of D in mono vacancy leading to the lower activation energy, where the dislocation loop and vacancy was produced. The third one was only found for the neutron irradiation, showing the D trapping by void or vacancy cluster and the diffusion effect is also contributed due to high FWHM of TDS spectrum. It can be said that the D 2 TDS spectra for Fe 2+ -irradiated tungsten could not represent that for neutron-irradiated one, showing that the deuterium trapping and desorption mechanism for neutron-irradiated tungsten has a difference from that for ion-irradiated one. (author)

Response of irradiated diet fed rats to whole body X irradiation

International Nuclear Information System (INIS)

Hasan, S.S.; Kushwaha, A.K.S.

1985-01-01

The response to whole body X irradiation has been studied in the brain of rats fed both on a normal diet (consisting of equal parts of wheat and gram flour) and on a low protein irradiated diet (consisting of a part of normal diet and three parts of wheat). The activity of enzymes related to the glucose metabolism (glucose 6-phosphate dehydrogenase and fructose diphosphate aldolase) is reduced, while that of peroxidant enzymes (catalase and lipid peroxidase) increased in the brain of rats that received a diet poor in proteins and irradiated diets (normal or hypoproteic). DNA and RNA levels and protein content show a significant reduction in the brain of rats with hypoproteic and irradiated diets. The total body irradiation causes serious alterations in the brain in animals with a hypoproteic malnutritions due both to a low protein and an irradiated diet. The brain of rats fed on a low protein and irradiated diet exhibits after whole body irradiation damages more severe than those in rats fed on a normal irradiated diet

Identification of irradiated foods prospects for post-irradiation estimate of irradiation dose in irradiated dry egg products

International Nuclear Information System (INIS)

Katusin-Raxem, B.; Mihaljievic, B.; Razem, D.

2002-01-01

Radiation-induced chemical changes in foods are generally very small at the usual processing doses. Some exception is radiation degradation of lipids, which are the components most susceptible to oxidation. A possible use of lipid hydroperoxides (LOOH) as indicators of irradiation is described for whole egg and egg yolk powders. A sensitive and reproducible spectrophotometric method for LOOH measurement based on feric thiocyanate, as modified in our laboratory, was applied. This method enabled the determination of LOOH, including oleic acid hydroperoxides, which is usually not possible with some other frequently used methods. The lowest limit of 0.05 mmol LOOH/kg lipid could be measured. The measurements were performed in various batches of whole egg and egg yolk powders by the same producer, as well as in samples supplied by various producers. Baseline level in unirradiated egg powder 0.110 ± 0.067 mmol LOOH /kgL was established. The formation of LOOH with dose, as well as the influence of age, irradiation conditions, storage time and storage conditions on LOOH were investigated. The irradiation of whole egg and egg yolk powders in the presence of air revealed an initially slow increase of LOOH, caused by an inherent antioxidative capacity, followed by a fast linear increase after the inhibition dose (D o ). In all investigated samples D o of 2 kGy was determined. Hydroperoxides produced in irradiated materials decay with time. In whole egg and egg yolk powders, after an initially fast decay, the level of LOOH continued to decrease by the first-order decay. Nevertheless, after a six months storage it was still possible to unambiguously identify samples which had been irradiated with 2 kGy in the presence of air. Reirradiation of these samples revealed a significant reduction of D o to 1 kGy. In samples irradiated with 4 kGy and kept under the same conditions, the shortening of D o to 0.5 kGy was determined by reirradiation. This offers a possibility for the

Post-irradiation examination and R and D programs using irradiated fuels at KAERI

International Nuclear Information System (INIS)

Chun, Yong Bum; Min, Duck Kee; Kim, Eun Ka and others

2000-12-01

This report describes the Post-Irradiation Examination(PIE) and R and D programs using irradiated fuels at KAERI. The objectives of post-irradiation examination (PIE) for the PWR irradiated fuels, CANDU fuels, HANARO fuels and test fuel materials are to verify the irradiation performance and their integrity as well as to construct a fuel performance data base. The comprehensive utilization program of the KAERI's post-irradiation examination related nuclear facilities such as Post-Irradiation Examination Facility (PIEF), Irradiated Materials Examination Facility (IMEF) and HANARO is described

Post-irradiation examination and R and D programs using irradiated fuels at KAERI

International Nuclear Information System (INIS)

Chun, Yong Bum; So, Dong Sup; Lee, Byung Doo; Lee, Song Ho; Min, Duck Kee

2001-09-01

This report describes the Post-Irradiation Examination(PIE) and R and D programs using irradiated fuels at KAERI. The objectives of post-irradiation examination (PIE) for the PWR irradiated fuels, CANDU fuels, HANARO fuels and test fuel materials are to verify the irradiation performance and their integrity as well as to construct a fuel performance data base. The comprehensive utilization program of the KAERI's post-irradiation examination related nuclear facilities such as Post-Irradiation Examination Facility (PIEF), Irradiated Materials Examination Facility (IMEF) and HANARO is described

Irradiation creep under 60 MeV alpha irradiation

International Nuclear Information System (INIS)

Reiley, T.C.; Shannon, R.H.; Auble, R.L.

1980-01-01

Accelerator-produced charged-particle beams have advantages over neutron irradiation for studying radiation effects in materials, the primary advantage being the ability to control precisely the experimental conditions and improve the accuracy in measuring effects of the irradiation. An apparatus has recently been built at ORNL to exploit this advantage in studying irradiation creep. These experiments employ a beam of 60 MeV alpha particles from the Oak Ridge Isochronous Cyclotron (ORIC). The experimental approach and capabilities of the apparatus are described. The damage cross section, including events associated with inelastic scattering and nuclear reactions, is estimated. The amount of helium that is introduced during the experiments through inelastic processes and through backscattering is reported. Based on the damage rate, the damage processes and the helium-to-dpa ratio, the degree to which fast reactor and fusion reactor conditions may be simulated is discussed. Recent experimental results on the irradiation creep of type 316 stainless steel are presented, and are compared to light ion results obtained elsewhere. These results include the stress and temperature dependence of the formation rate under irradiation. The results are discussed in relation to various irradiation creep mechanisms and to damage microstructure as it evolves during these experiments. (orig.)

Food irradiation: An update

International Nuclear Information System (INIS)

Morrison, Rosanna M.

1984-01-01

Recent regulatory and commercial activity regarding food irradiation is highlighted. The effects of irradiation, used to kill insects and microorganisms which cause food spoilage, are discussed. Special attention is given to the current regulatory status of food irradiation in the USA; proposed FDA regulation regarding the use of irradiation; pending irradiation legislation in the US Congress; and industrial applications of irradiation

U-turn type continuous irradiation method and device for radiation-irradiated capsule

International Nuclear Information System (INIS)

Kikuchi, Takayuki.

1997-01-01

A capsule to be irradiated is moved while being rotated in one of conveying shafts disposed in a reactor to conduct irradiation treatment. Then, the irradiated capsule is made U-turn in the reactor, inserted to the other conveying shaft and moved while being rotated to conduct irradiation treatment again, and then transported out of the reactor. The device comprises a rotational conveying shaft for moving the irradiated capsule while rotating it, a conveying gear for U-turning the irradiated capsule in the reactor and inserting it to the conveying shaft and a driving mechanism for synchronously rotating the conveying gear relative to the conveying shaft at a constant ratio. Mechanical time loss and manual operation time loss can be reduced upon loading and taking up of the irradiated capsule. Then, the amount of irradiation treatment per unit time is increased, and an optional neutron irradiation amount can be obtained thereby enabling to reduce operator's radiation exposure. (N.H.)

Modelling property changes in graphite irradiated at changing irradiation temperature

CSIR Research Space (South Africa)

Kok, S

2011-01-01

Full Text Available A new method is proposed to predict the irradiation induced property changes in nuclear; graphite, including the effect of a change in irradiation temperature. The currently used method; to account for changes in irradiation temperature, the scaled...

Irradiation of foodstuffs

International Nuclear Information System (INIS)

Sjoeberg, A.M.

1993-01-01

Foodstuffs are irradiated to make them keep better. The ionizing radiation is not so strong as to cause radioactivity in the foodstuffs. At least so far, irradiation has not gained acceptance among consumers, although it has been shown to be a completely safe method of preservation. Irradiation causes only slight chemical changes in food. What irradiation does, however, is to damage living organisms, such as bacteria, DNA and proteins, thereby making the food keep longer. Irradiation can be detected from the food afterwards; thus it can be controlled effectively. (orig.)

Tissue irradiator

International Nuclear Information System (INIS)

Hungate, F.P.; Riemath, W.F.; Bunnell, L.R.

1975-01-01

A tissue irradiator is provided for the in-vivo irradiation of body tissue. The irradiator comprises a radiation source material contained and completely encapsulated within vitreous carbon. An embodiment for use as an in-vivo blood irradiator comprises a cylindrical body having an axial bore therethrough. A radioisotope is contained within a first portion of vitreous carbon cylindrically surrounding the axial bore, and a containment portion of vitreous carbon surrounds the radioisotope containing portion, the two portions of vitreous carbon being integrally formed as a single unit. Connecting means are provided at each end of the cylindrical body to permit connections to blood-carrying vessels and to provide for passage of blood through the bore. In a preferred embodiment, the radioisotope is thulium-170 which is present in the irradiator in the form of thulium oxide. A method of producing the preferred blood irradiator is also provided, whereby nonradioactive thulium-169 is dispersed within a polyfurfuryl alcohol resin which is carbonized and fired to form the integral vitreous carbon body and the device is activated by neutron bombardment of the thulium-169 to produce the beta-emitting thulium-170

Food irradiation

International Nuclear Information System (INIS)

Migdal, W.

1995-01-01

A worldwide standard on food irradiation was adopted in 1983 by codex Alimentarius Commission of the Joint Food Standard Programme of the Food and Agriculture Organization (FAO) of the United Nations and The World Health Organization (WHO). As a result, 41 countries have approved the use of irradiation for treating one or more food items and the number is increasing. Generally, irradiation is used to: food loses, food spoilage, disinfestation, safety and hygiene. The number of countries which use irradiation for processing food for commercial purposes has been increasing steadily from 19 in 1987 to 33 today. In the frames of the national programme on the application of irradiation for food preservation and hygienization an experimental plant for electron beam processing has been established in Inst. of Nuclear Chemistry and Technology. The plant is equipped with a small research accelerator Pilot (19 MeV, 1 kW) and industrial unit Electronika (10 MeV, 10 kW). On the basis of the research there were performed at different scientific institutions in Poland, health authorities have issued permissions for irradiation for; spices, garlic, onions, mushrooms, potatoes, dry mushrooms and vegetables. (author)

Food irradiation

International Nuclear Information System (INIS)

1991-01-01

Processing of food with low levels of radiation has the potential to contribute to reducing both spoilage of food during storage - a particular problem in developing countries - and the high incidence of food-borne disease currently seen in all countries. Approval has been granted for the treatment of more than 30 products with radiation in over 30 countries but, in general, governments have been slow to authorize the use of this new technique. One reason for this slowness is a lack of understanding of what food irradiation entails. This book aims to increase understanding by providing information on the process of food irradiation in simple, non-technical language. It describes the effects that irradiation has on food, and the plant and equipment that are necessary to carry it out safely. The legislation and control mechanisms required to ensure the safety of food irradiation facilities are also discussed. Education is seen as the key to gaining the confidence of the consumers in the safety of irradiated food, and to promoting understanding of the benefits that irradiation can provide. (orig.) With 4 figs., 1 tab [de

Irradiation damage

International Nuclear Information System (INIS)

Howe, L.M.

2000-01-01

There is considerable interest in irradiation effects in intermetallic compounds from both the applied and fundamental aspects. Initially, this interest was associated mainly with nuclear reactor programs but it now extends to the fields of ion-beam modification of metals, behaviour of amorphous materials, ion-beam processing of electronic materials, and ion-beam simulations of various kinds. The field of irradiation damage in intermetallic compounds is rapidly expanding, and no attempt will be made in this chapter to cover all of the various aspects. Instead, attention will be focused on some specific areas and, hopefully, through these, some insight will be given into the physical processes involved, the present state of our knowledge, and the challenge of obtaining more comprehensive understanding in the future. The specific areas that will be covered are: point defects in intermetallic compounds; irradiation-enhanced ordering and irradiation-induced disordering of ordered alloys; irradiation-induced amorphization

Irradiation damage

Energy Technology Data Exchange (ETDEWEB)

Howe, L.M

2000-07-01

There is considerable interest in irradiation effects in intermetallic compounds from both the applied and fundamental aspects. Initially, this interest was associated mainly with nuclear reactor programs but it now extends to the fields of ion-beam modification of metals, behaviour of amorphous materials, ion-beam processing of electronic materials, and ion-beam simulations of various kinds. The field of irradiation damage in intermetallic compounds is rapidly expanding, and no attempt will be made in this chapter to cover all of the various aspects. Instead, attention will be focused on some specific areas and, hopefully, through these, some insight will be given into the physical processes involved, the present state of our knowledge, and the challenge of obtaining more comprehensive understanding in the future. The specific areas that will be covered are: point defects in intermetallic compounds; irradiation-enhanced ordering and irradiation-induced disordering of ordered alloys; irradiation-induced amorphization.

Hemibody irradiation

International Nuclear Information System (INIS)

Schen, B.C.; Mella, O.; Dahl, O.

1992-01-01

In a large number of cancer patients, extensive skeletal metastases or myelomatosis induce vast suffering, such as intolerable pain and local complications of neoplastic bone destruction. Analgetic drugs frequently do not yield sufficient palliation. Irradiation of local fields often has to be repeated, because of tumour growth outside previously irradiated volumes. Wide field irradiation of the lower or upper half of the body causes significant relief of pain in most patients. Adequate pretreatment handling of patients, method of irradiation, and follow-up are of importance to reduce side effects, and are described as they are carried out at the Department of Oncology, Haukeland Hospital, Norway. 16 refs., 2 figs

Bakery products from irradiated and non-irradiated eggs - analytical problems associated with the detection of irradiation in processed foods

International Nuclear Information System (INIS)

Grabowski, H.U. von; Pfordt, J.

1993-01-01

In spring and early summer 1992, a number of irradiated egg products were illegally imported into Germay. To prove the irradiation of these egg products, mainly combined gas chromatography-mass spectrometry was applied. With this present study we wanted to answer the question if we were also able to detect the use of irradiated eggs in processed foods. The processed food we chose to produce and to investigate was a tart layer. For this product, dilution effects are of minor importance as no extra fat was added. Thus, the layers' fat almost exclusively came from the eggs. To study the influence of emulsifiers, we produced batters both with and without adding an emulsifer. The unsaturted hydrocarbons C14:1, C16:3, C16:2, C17:2, and C17:1 served as markers for an irradiation. In the non-irradiated egg samples and in the tart layers produced from them, these compounds could not be detected (or in some cases only in small amounts). They were, however, detectable in all irradiated samples. DCB could be found in all irradiated egg samples and in the tart layers that were baked from irradiated eggs. It was not present in non-irradiated eggs and in tart layers produced from them. (orig./Vhe)

Embrittlement of irradiated ferritic/martensitic steels in the absence of irradiation hardening

Energy Technology Data Exchange (ETDEWEB)

Klueh, R.L. [Oak Ridge Noational Laboratory, TN (United States); Shiba, K. [Japan Atomic Energy Agency, Tokai-mura, Naga-gun, Ibaraki-ken (Japan); Sokolov, M. [Oak Ridge National Laboratory, Materials Science and Technology Div., TN (United States)

2007-07-01

Full text of publication follows: Neutron irradiation of 9-12% Cr ferritic/martensitic steels below 425-450 deg. C produces microstructural defects that cause an increase in yield stress and ultimate tensile strength. This irradiation hardening causes embrittlement, which is observed in Charpy impact and toughness tests as an increase in ductile-brittle transition temperature (DBTT). Based on observations that show little change in strength in these steels irradiated above 425-450 deg. C, the general conclusion has been that no embrittlement occurs above this irradiation-hardening temperature regime. In a recent study of F82H steel irradiated at 300, 380, and 500 deg. C, irradiation hardening-an increase in yield stress-was observed in tensile specimens irradiated at the two lower temperatures, but no change was observed for the specimens irradiated at 500 deg. C. As expected, an increase in DBTT occurred for the Charpy specimens irradiated at 300 and 380 deg. C. However, there was an unexpected increase in the DBTT of the specimens irradiated at 500 deg. C. The observed embrittlement was attributed to the irradiation-accelerated precipitation of Laves phase. This conclusion was based on results from a detailed thermal aging study of F82H, in which tensile and Charpy specimens were aged at 500, 550, 600, and 650 deg. C to 30,000 h. These studies indicated that there was a decrease in yield stress at the two highest temperatures and essentially no change at the two lowest temperatures. Despite the strength decrease or no change, the DBTT increased for Charpy specimens irradiated at all four temperatures. Precipitates were extracted from thermally aged specimens, and the amount of precipitate was correlated with the increase in transition temperature. Laves phase was identified in the extracted precipitates by X-ray diffraction. Earlier studies on conventional elevated-temperature steels also showed embrittlement effects above the irradiation-hardening temperature

Neutron Flux Characterization of Irradiation Holes for Irradiation Test at HANARO

Directory of Open Access Journals (Sweden)

Yang Seong Woo

2016-01-01

Full Text Available The High flux Advanced Neutron Application ReactOr (HANARO is a unique research reactor in the Republic of Korea, and has been used for irradiation testing since 1998. To conduct irradiation tests for nuclear materials, the irradiation holes of CT and OR5 have been used due to a high fast-neutron flux. Because the neutron flux must be accurately calculated to evaluate the neutron fluence of irradiated material, it was conducted using MCNP. The neutron flux was measured using fluence monitor wires to verify the calculated result. Some evaluations have been conducted, however, more than 20% errors have frequently occurred at the OR irradiation hole, while a good agreement between the calculated and measured data was shown at the CT irradiation hole.

Behavior of high Tc-superconductors and irradiated defects under reactor irradiation

International Nuclear Information System (INIS)

Atobe, Kozo; Honda, Makoto; Fukuoka, Noboru; Yoshida, Hiroyuki.

1991-01-01

It has been well known that the lattice defects of various types are introduced in ceramics without exception, and exert large effect to the function of these materials. Among oxides, the electronic materials positively using oxygen defect control have been already put in practical use. Also in the oxide high temperature superconductors which are Perovskite type composite oxides, the superconductive characteristics are affected largely by the concentration of the oxygen composing them. This is regarded as an important factor for causing superconductivity, related with the oxygen cavities arising at this time and the carriers bearing superconductivity. In this study, the irradiation effect with relatively low dose, the measurement under irradiation, the effect of irradiation temperature, and the effect of radiation quality were evaluated by the irradiation of YBCO, EBCO and LBCO. The experimental method, and the irradiation effect at low temperature and normal temperature, the effect of Co-60 gamma ray irradiation instead of reactor irradiation are reported. (K.I.)

Electron beam irradiating device

Energy Technology Data Exchange (ETDEWEB)

Shinohara, K

1969-12-20

The efficiency of an electron beam irradiating device is heightened by improving the irradiation atmosphere and the method of cooling the irradiation window. An irradiation chamber one side of which incorporates the irradiation windows provided at the lower end of the scanner is surrounded by a suitable cooling system such as a coolant piping network so as to cool the interior of the chamber which is provided with circulating means at each corner to circulate and thus cool an inert gas charged therewithin. The inert gas, chosen from a group of such gases which will not deleteriously react with the irradiating equipment, forms a flowing stream across the irradiation window to effect its cooling and does not contaminate the vacuum exhaust system or oxidize the filament when penetrating the equipment through any holes which the foil at the irradiation window may incur during the irradiating procedure.

Food irradiation

International Nuclear Information System (INIS)

Kobayashi, Yasuhiko; Kikuchi, Masahiro

2009-01-01

Food irradiation can have a number of beneficial effects, including prevention of sprouting; control of insects, parasites, pathogenic and spoilage bacteria, moulds and yeasts; and sterilization, which enables commodities to be stored for long periods. It is most unlikely that all these potential applications will prove commercially acceptable; the extend to which such acceptance is eventually achieved will be determined by practical and economic considerations. A review of the available scientific literature indicates that food irradiation is a thoroughly tested food technology. Safety studies have so far shown no deleterious effects. Irradiation will help to ensure a safer and more plentiful food supply by extending shelf-life and by inactivating pests and pathogens. As long as requirement for good manufacturing practice are implemented, food irradiation is safe and effective. Possible risks of food irradiation are not basically different from those resulting from misuse of other processing methods, such as canning, freezing and pasteurization. (author)

Facts about food irradiation: Microbiological safety of irradiated food

International Nuclear Information System (INIS)

1991-01-01

This fact sheet considers the microbiological safety of irradiated food, with especial reference to Clostridium botulinum. Irradiated food, as food treated by any ''sub-sterilizing'' process, must be handled, packaged and stored following good manufacturing practices to prevent growth and toxin production of C. botulinum. Food irradiation does not lead to increased microbiological hazards, nor can it be used to save already spoiled foods. 4 refs

Total body irradiation: current indications; L`irradiation corporelle totale: les indications actuelles

Energy Technology Data Exchange (ETDEWEB)

Giraud, P.; Danhier, S.; Dubray, B.; Cosset, J.M. [Institut Curie, 75 - Paris (France)

1998-05-01

The choice of dose and fractionation for total body irradiation is made difficult by the large number of considerations to be taken into account. The outcome of bone marrow transplantation after total body irradiation can be understood in terms of tumor cell killing, engraftment, and normal tissue damage, each of these endpoints being influenced by irradiation-, disease-, transplant-, and patient- related factors. Interpretation of clinical data is further hampered by the overwhelming influence of logistic constraints, the small numbers of randomized studies, and the concomitant variations in total dose and fraction size or dose rate. So far, three cautious conclusions can be drawn in order to tentatively adapt the total body irradiation schedule to clinically-relevant situations. Firstly, the organs at risk for normal tissue damage (lung, liver, lens, kidney) are protected by delivering small doses per fraction at low dose rate. This suggests that, when toxicity is at stake (e.g. in children), fractionated irradiation should be preferred, provided that inter-fraction intervals are long enough. Secondly, fractionated irradiation should be avoided in case of T-cell depleted transplant, given the high risk of graft rejection in this setting. An alternative would be to increase total (or fractional) dose of fractionated total body irradiation, but this approach is likely to induce more normal tissue toxicity. Thirdly, clinical data have shown higher relapse rates in chronic myeloid leukemia after fractionated or low dose rate total body irradiation, suggesting that fractionated irradiation should not be recommended, unless total (or fractional) dose is increased. Total body irradiation-containing regimens, primarily cyclophosphamide / total body irradiation, are either equivalent to or better than the chemotherapy-only regimens, primarily busulfan / cyclophosphamide. Busulfan / cyclophosphamide certainly represents a reasonable alternative, especially in patients who

Food irradiation

International Nuclear Information System (INIS)

Paganini, M.C.

1991-06-01

Food treatment by means of ionizing energy, or irradiation, is an innovative method for its preservation. In order to treat important volumes of food, it is necessary to have industrial irradiation installations. The effect of radiations on food is analyzed in the present special work and a calculus scheme for an Irradiation Plant is proposed, discussing different aspects related to its project and design: ionizing radiation sources, adequate civil work, security and auxiliary systems to the installations, dosimetric methods and financing evaluation methods of the project. Finally, the conceptual design and calculus of an irradiation industrial plant of tubercles is made, based on the actual needs of a specific agricultural zone of our country. (Author) [es

Biology of food irradiation

International Nuclear Information System (INIS)

Murray, D.R.

1990-01-01

The author presents his arguments for food scientists and biologists that the hazards of food irradiation outweigh the benefits. The subject is discussed in the following sections: introduction (units, mutagenesis, seed viability), history of food irradiation, effects of irradiation on organoleptic qualities of staple foods, radiolytic products and selective destruction of nutrients, production of microbial toxins in stored irradiated foods and loss of quality in wheat, deleterious consequences of eating irradiated foods, misrepresentation of the facts about food irradiation. (author)

DAMAGE IN MOLYBDENUM ASSOCIATED WITH NEUTRON IRRADIATION AND SUBSEQUENT POST-IRRADIATION ANNEALING

Energy Technology Data Exchange (ETDEWEB)

Mastel, B.

1963-07-23

Molybdemum containing carbon was studied in an attempt to establish the combined effect of impurity content and neutron irradiation on the properties and structure of specific metals. Molybdenum foils were punched into discs and heat treated in vacuum. They were then slow-cooled and irradiated. After irradiation and subsequent decay of radioactivity to a low level the foils were subjected to x-ray diffraction measurements. Cold-worked foils with less than 10 ppm carbon showed no change in microstructure due to irradiation. Molybdenum foils that were annealed prior to irradiation showed spot defects. In foils containing up to 500 ppm carbon, it was concluded that the small loops present after irradiation are due to the clustering of point defects at interstitial carbon atoms, followed by collapse to form a dislocation loop. The amount of lattice expansion after irradiation was strongly dependent on impurity content. Neutron irradiation was found to reduce the number of active slip systems. (M.C.G.)

Perspective on food irradiation

International Nuclear Information System (INIS)

Newsome, R.L.

1987-01-01

A brief review summarizes current scientific information on the safety and efficacy of irradiation processing of foods. Attention is focused on: specifics of the irradiation process and its effectiveness in food preservation; the historical development of food irradiation technology in the US; the response of the Institute of Food Technologists to proposed FDA guidelines for food irradiation; the potential uses of irradiation in the US food industry; and the findings of the absence of toxins and of unaltered nutrient density (except possibly for fats) in irradiated foods. The misconceptions of consumers concerning perceived hazards associated with food irradiation, as related to consumer acceptance, also are addressed

Fabrication of irradiation capsule for IASCC irradiation tests (2). Irradiation capsule for crack propagation test (Joint research)

International Nuclear Information System (INIS)

Ide, Hiroshi; Matsui, Yoshinori; Kawamata, Kazuo; Taguchi, Taketoshi; Kanazawa, Yoshiharu; Onuma, Yuichi; Watanabe, Hiroyuki; Inoue, Shuichi; Izumo, Hironobu; Ishida, Takuya; Saito, Takashi; Ishitsuka, Etsuo; Kawamura, Hiroshi; Kaji, Yoshiyuki; Ugachi, Hirokazu; Tsukada, Takashi

2008-03-01

It is known that irradiation Assisted Stress Corrosion Cracking (IASCC) occurs when austenitic stainless steel components used for light water reactor (LWR) are irradiated for a long period. In order to evaluate the high aging of the nuclear power plant, the study of IASCC becomes the important problem. The specimens irradiated in the reactor were evaluated by post irradiation examination in the past study. For the appropriate evaluation of IASCC, it is necessary to test it under the simulated LWR conditions; temperature, water chemistry and irradiation conditions. In order to perform in-pile SCC test, saturated temperature capsule (SATCAP) was developed. There are crack growth test, crack propagation test and so on for in-pile SCC test. In this report, SATCAP for crack propagation test is reported. (author)

Fabrication of irradiation capsule for IASCC irradiation tests (1). Irradiation capsule for crack growth test (Joint research)

International Nuclear Information System (INIS)

Ide, Hiroshi; Matsui, Yoshinori; Kawamata, Kazuo; Taguchi, Taketoshi; Kanazawa, Yoshiharu; Onuma, Yuichi; Watanabe, Hiroyuki; Inoue, Shuichi; Izumo, Hironobu; Ishida, Takuya; Saito, Takashi; Ishitsuka, Etsuo; Kawamura, Hiroshi; Kaji, Yoshiyuki; Ugachi, Hirokazu; Tsukada, Takashi

2008-03-01

It is known that Irradiation Assisted Stress Corrosion Cracking (IASCC) occurs when austenitic stainless steel components used for light water reactor (LWR) are irradiated for a long period. In order to evaluate the high aging of the nuclear power plant, the study of IASCC becomes the important problem. The specimens irradiated in the reactor were evaluated by post irradiation examination in the past study. For the appropriate evaluation of IASCC, it is necessary to test it under the simulated LWR conditions; temperature, water chemistry and irradiation conditions. In order to perform in-pile SCC test, saturated temperature capsule (SATCAP) was developed. There are crack growth test, crack propagation test and so on for in-pile SCC test. In this report, SATCAP for crack growth test is reported. (author)

Irradiation of foodstuffs

International Nuclear Information System (INIS)

Bugyaki, L.

1977-01-01

The author studies the criteria for the harmlessness of irradiation as a food-preservation process. The glucose and proteins of bacto-tryptone, irradiated at 5 Mrads, do not increase the Escherichia Coli C 600 lysogenous bacteriophages, compared to the induction produced by direct irradiation of the strain or to the exposition to nitrogenous yperite. The possible mutagenic effect is therefore different. Wheat flour freshly irradiated at 5 Mrads shows physico-chemical changes. When given to mice as 50% of their ration, it leads to a higher incidence of tumours and a greater number of meiotic chromosome alteration (besides some discreet physio-pathological changes in fertility and longevity). Immunoelectrophoresis in agar or agarose gel does not allow any detection of irradiation of meat, fish or eggs. A vertical electrophoresis in starch gel can lead to a differentiation between frozen or chilled meat and the one that is irradiated at 0.5 or 5 Mrads, but the same thing can't be said for fish or eggs. Lastly an irradiated mushroom shows every sign of freshness but, when planted in a suitable medium, its cuttings do not present any cell proliferation which could give a rapid and simple method of detecting the irradiation. (G.C.)

Blood irradiation

International Nuclear Information System (INIS)

Chandy, Mammen

1998-01-01

Viable lymphocytes are present in blood and cellular blood components used for transfusion. If the patient who receives a blood transfusion is immunocompetent these lymphocytes are destroyed immediately. However if the patient is immunodefficient or immunosuppressed the transfused lymphocytes survive, recognize the recipient as foreign and react producing a devastating and most often fatal syndrome of transfusion graft versus host disease [T-GVHD]. Even immunocompetent individuals can develop T-GVHD if the donor is a first degree relative since like the Trojan horse the transfused lymphocytes escape detection by the recipient's immune system, multiply and attack recipient tissues. T-GVHD can be prevented by irradiating the blood and different centers use doses ranging from 1.5 to 4.5 Gy. All transfusions where the donor is a first degree relative and transfusions to neonates, immunosuppressed patients and bone marrow transplant recipients need to be irradiated. Commercial irradiators specifically designed for irradiation of blood and cellular blood components are available: however they are expensive. India needs to have blood irradiation facilities available in all large tertiary institutions where immunosuppressed patients are treated. The Atomic Energy Commission of India needs to develop a blood irradiator which meets international standards for use in tertiary medical institutions in the country. (author)

Study of the recrystallisation of irradiated uranium; Etude sur l'uranium irradie

Energy Technology Data Exchange (ETDEWEB)

Bloch, J; Mustelier, J P; Bussy, P; Blin, J [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

1958-07-01

1- Study of the recrystallisation of irradiated uranium. The recrystallisation of uranium irradiated to a burnup level of 220 MWj/t, at a temperature of the order of 350 deg. C, has been investigated. The observations were made chiefly by means of micrography an hardness measurements. If the irradiated metal is compared with a cold-drawn metal showing the same shearing of the twinned crystals, and therefore the same rate of plastic deformation, as the irradiated metal, it is noted that the restoring of the irradiated metal takes place at a considerably higher temperature than that of the cold-drawn metal. Pre-crystallisation is very much delayed. Only, a passage of the {alpha}-{beta} transformation point quickly wipes out irradiation effect. 2- Hardening of uranium by irradiation. Using hardness measurements we have studied more especially the effect of very weak irradiations on uranium (integrated flux < 10{sup 16} nvt). The hardness does not increase linearly with the flux, but a period of incubation is observed probably representing the time necessary for saturation of the dislocations. (author)Fren. [French] 1- Etude de la recristallisation de l'uranium irradie. On a etudie la recristallisation d'uranium irradie jusqu'a un taux de combustion de 220 MWj/t a une temperature de l'ordre de 350 deg. C. Les observations ont ete faites principalement a l'aide de la micrographie et de la durete. Si l'on compare le metal irradie avec un metal ecroui presentant le meme cisaillement des macles, donc le meme taux de deformation plastique que le metal irradie, on constate que la restauration du metal irradie se fait a une temperature notablement superieure a celle du metal ecroui. La recristallisation est tres retardee. Seul, un passage du point de transformation {alpha}-{beta} efface rapidement l'effet de l'irradiation. 2- Durcissement de l'uranium par irradiation. Nous avons, a l'aide de la durete, etudie plus particulierement l'effet de tres faibles irrtions sur l

Property changes in graphite irradiated at changing irradiation temperature

International Nuclear Information System (INIS)

Price, R.J.; Haag, G.

1979-07-01

Design data for irradiated graphite are usually presented as families of isothermal curves showing the change in physical property as a function of fast neutron fluence. In this report, procedures for combining isothermal curves to predict behavior under changing irradiation temperatures are compared with experimental data on irradiation-induced changes in dimensions, Young's modulus, thermal conductivity, and thermal expansivity. The suggested procedure fits the data quite well and is physically realistic

Process and apparatus for irradiating film, and irradiated film

International Nuclear Information System (INIS)

1981-01-01

A process for irradiating film is described, which consists of passing the film through an electron irradiation zone having an electron reflection surface disposed behind and generally parallel to the film; and disposing within the irradiation zone adjacent the edges of the film a lateral reflection member for reflecting the electrons toward the reflection surface to further reflect the reflected electrons towards the adjacent edges of the film. (author)

Irradiation enhanced diffusion and irradiation creep tests in stainless steel alloys

International Nuclear Information System (INIS)

Loelgen, R.H.; Cundy, M.R.; Schuele, W.

1977-01-01

A review is given of investigations on the rate of phase changes during neutron and electron irradiation in many different fcc alloys showing either precipitation or ordering. The diffusion rate was determined as a function of the irradiation flux, the irradiation temperature and the irradiation dose. It was found that the radiation enhanced diffusion in all the investigated alloys is nearly temperature independent and linearly dependent on the flux. From these results conclusions were drawn concerning the properties of point defects and diffusion mechanisms rate determining during irradiation, which appears to be of a common nature for fcc alloys having a similar structure to those investigated. It has been recognized that the same dependencies which are found for the diffusion rate were also observed for the irradiation creep rate in stainless steels, as reported in literature. On the basis of this observation a combination of measurements is suggested, of radiation enhanced diffusion and radiation enhanced creep in stainless steel alloys. The diffusion tests will be performed at the Euratom Joint Research Centre in Ispra, Italy, and the irradiation creep tests will be carried out in the High Flux Reactor /9/ of the Euratom Joint Research Centre in Petten, The Netherlands. In order to investigate irradiation creep on many samples at a time two special rigs were developed which are distinguished only by the mode of stress applied to the steel specimens. In the first type of rig about 50 samples can be tested uniaxially under tension with various combinations of irradiation temperature and stress. The second type of rig holds up to 70 samples which are tested in bending, again with various combinations of irradiation temperature and stress

Technical review on irradiation tests and post-irradiation examinations in JMTR

International Nuclear Information System (INIS)

2017-07-01

The Japan Materials Testing Reactor (JMTR) has been contributing to various R and D activities in the nuclear research such as the fundamental research of nuclear materials/ fuels, safety research and development of power reactors, radio isotope (RI) production since its beginning of the operation in 1968. Irradiation technologies and post irradiation examination (PIE) technologies are the important factors for irradiation test research. Moreover, these technologies induce the breakthrough in area of nuclear research. JMTR has been providing unique capabilities for the irradiation test research for about 40 years since 1968. In future, any needs for irradiation test research used irradiation test reactors will continue, such as R and D of generation 4 power reactors, fundamental research of materials/fuels, RI production. Now, decontamination and new research reactor construction are common issue in the world according to aging. This situation is the same in Japan. This report outlines irradiation and PIE technologies developed at JMTR in 40 years to contribute to the technology transfer and human resource development. We hope that this report will be used for the new research rector design as well as the irradiation test research and also used for the human resource development of nuclear engineers in future. (author)

Effect of medium and post-irradiation storage on rooting of irradiated onions

International Nuclear Information System (INIS)

Singh, Rita

2000-01-01

Rooting test for detection of irradiation in onion bulbs was studied. Onions were exposed to different dose levels of 30, 60, 90, 120 and 150 Gy. The effects of irradiation dose, cultivar difference, rooting medium and post-irradiation storage on the rooting were investigated. The number and the length of the roots formed in onions were found to decrease on irradiation. The effect was more at higher doses. The effect of irradiation on rooting was also evident after 120 days of storage. (author)

Irradiation and flavor

International Nuclear Information System (INIS)

Reineccius, G.A.

1992-01-01

Flavor will not be a significant factor in determining the success of irradiated foods entering the U.S. market. The initial applications will use low levels of irradiation that may well result in products with flavor superior to that of products from alternative processing techniques (thermal treatment or chemical fumigation). The success of shelf-stable foods produced via irradiation may be much more dependent upon our ability to deal with the flavor aspects of high levels of irradiation

Dosimetry and irradiation methods for the ANSTO gamma technology research irradiator (GATRI)

International Nuclear Information System (INIS)

Izard, M.E.

1988-07-01

The Australian Nuclear Science and Technology Organisation's gamma technology research irradiator (GATRI) at Lucas Heights, New South Wales, has been modified for use as a research and small-scale commercial irradiation facility to be available to government agencies and private industry for the technical and economic evaluation of irradiation processing. The new source rack was designed around existing mechanical components to optimise the limited space available within the irradiation cell. Irradiation parameters investigated during commissioning included the effect of source-to-target distance on relative dose rates within targets of the same density; effect of density on dose-rate distribution within targets irradiated at the same distance from the source; and the contribution of transit dose to low absorbed doses as the source is raised and lowered. The efficiency of the irradiator was determined for various target densities and overdose ratios

The influence of late-stage pupal irradiation and increased irradiated: un-irradiated male ratio on mating competitiveness of the malaria mosquito Anopheles arabiensis Patton.

Science.gov (United States)

Helinski, M E H; Knols, B G J

2009-06-01

Competitiveness of released males in genetic control programmes is of critical importance. In this paper, we explored two scenarios to compensate for the loss of mating competitiveness after pupal stage irradiation in males of the malaria mosquito Anopheles arabiensis. First, competition experiments with a higher ratio of irradiated versus un-irradiated males were performed. Second, pupae were irradiated just prior to emergence and male mating competitiveness was determined. Males were irradiated in the pupal stage with a partially or fully-sterilizing dose of 70 or 120 Gy, respectively. Pupae were irradiated aged 20-26 h (young) as routinely performed, or the pupal stage was artificially prolonged by cooling and pupae were irradiated aged 42-48 h (old). Irradiated males competed at a ratio of 3:1:1 to un-irradiated males for mates in a large cage design. At the 3:1 ratio, the number of females inseminated by males irradiated with 70 Gy as young pupae was similar to the number inseminated by un-irradiated males for the majority of the replicates. At 120 Gy, significantly fewer females were inseminated by irradiated than by un-irradiated males. The irradiation of older pupae did not result in a significantly improved male mating competitiveness compared to the irradiation of young pupae. Our findings indicate that the loss of competitiveness after pupal stage irradiation can be compensated for by a threefold increase of irradiated males, but only for the partially-sterilizing dose. In addition, cooling might be a useful tool to facilitate handling processes of large numbers of mosquitoes in genetic control programmes.

New Methods and Facilities for the Measurement of Physical Properties of Reactor Components and Irradiated Materials; Nouveaux Procedes et Instruments de Mesure des Proprietes Physiques des Elements de Reacteur et des Matieres Irradiees; Novye metody i sredstva izmereniya fizicheskikh s vojstv komponentov reaktora i obluchennykh materialov; Nuevos Metodos y Equipos para Medir Propiedades Fisicas de Componentes de Reactor y de Materiales Irradiados

Energy Technology Data Exchange (ETDEWEB)

Foerster, F.; Mueller, P. [Institut Dr. Foerster, Reutlingen, Federal Republic of Germany (Germany)

1965-09-15

direct reading of the permeability and stainless- steel components. The correlation between permeability and {Delta} ferrite content is explained. Measurements of the {Delta} ferrite percentage across welds in stainless-steel tubes and measurements of the {Delta} ferrite precipitations as a function of the plastic strain are discussed (hammer-forging of reactor fuel-elements). (author) [French] Les auteurs decrivent un instrument permettant de mesurer et d'enregistrer automatiquement le module de Young, le module de cisaillement et la capacite d'amortissement en fonction de la temperature et du temps. On mesure le module de Young en excitant des specimens de diverses dimensions a leur frequence propre. On mesure la capacite d'amortissement d'apres la libre decroissance de la vibration ou la largeur a mi-hauteur de la courbe de resonance. Le memoire donne des exemples de mesures de la guerison apres irradiation et apres deformation inelastique, ainsi que des exemples du degre de graphitisation. Les auteurs demontrent que l'on peut detecter des defauts et des variations de densite dans les banes de graphite. Ils expliquent, en outre, une methode d'etude de la fixation de pastilles d' UO{sub 2} sur des tubes en acier austenitique a parois minces. Us decrivent un four special pour l'etude du comportement elastique ou inelastique de specimens 'chauds ' a des temperatures variant entre 20 et 1000 Degree-Sign C. Les auteurs discutent le controle de la qualite de metaux non ferreux par mesure de ia conductivite electrique au moyen de courants de Foucault et decrivent un instrument permettant de mesurer sans aucun contact la conductivite electrique de metaux non ferreux. Ils expliquent la correlation entre la conductivite electrique et l'allongement sous l'effet des contraintes dans le cas de metaux et d'alliages non ferreux. Ils s'attachent particulierement a la mesure d'echantillons de petites dimensions. Ils decrivent un dispositif pour la mesure directe a distance dans la

Irradiation device

International Nuclear Information System (INIS)

Suzuki, Toshimitsu.

1989-01-01

In an irradiation device for irradiating radiation rays such as electron beams to pharmaceuticals, etc., since the distribution of scanned electron rays was not monitored, the electron beam intensity could be determined only indirectly and irradiation reliability was not satisfactory. In view of the above, a plurality of monitor wires emitting secondary electrons are disposed in the scanning direction near a beam take-out window of a scanning duct, signals from the monitor wires are inputted into a display device such as a cathode ray tube, as well as signals from the monitor wires at the central portion are inputted into counting rate meters to measure the radiation dose as well. Since secondary electrons are emitted when electron beams pass through the monitor wires and the intensity thereof is in proportion with the intensity of incident electron beams, the distribution of the radiation dose can be monitored by measuring the intensity of the emitted secondary electrons. Further, uneven irradiation, etc. can also be monitored to make the radiation of irradiation rays reliable. (N.H.)

Sensory properties of irradiated foods

International Nuclear Information System (INIS)

Plestenjak, A.

1997-01-01

Food irradiation is a simple and effective preservation technique. The changes caused by irradiation depend on composition of food, on the absorbed dose, the water content and temperature during and after irradiation. In this paper the changes of food components caused by irradiation, doses for various food irradiation treatments, foods and countries where the irradiation is allowed, and sensory properties of irradiated food are reviewed

Irradiation-Induced Nanostructures

Energy Technology Data Exchange (ETDEWEB)

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

1999-08-09

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

The compatibility of chromium-aluminium steels with high pressure carbon dioxid at intermediate- temperatures; Compatibilite des aciers au chrome-aluminium avec le gaz carbonique sous pression aux temperatures moyennes

Energy Technology Data Exchange (ETDEWEB)

Leclercq, D; Loriers, H; David, R; Darras, E [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

1964-07-01

With a view to their use in the exchangers of nuclear reactors of the graphite-gas or heavy water-gas types, the behaviour of chromium-aluminium steels containing up to 7 per cent chromium and 1.5 per cent aluminium has been studied in the presence of high-pressure carbon dioxide at temperatures of between 400 and 700 deg. C. The two most interesting grades of steel (2 per cent Cr - 0.35 per cent Al - 0.35 per cent Mo and 7 per cent Cr - 1.5 per cent Al - 0.6 per cent Si) are still compatible with carbon dioxide up to 550 and 600 deg. C respectively. A hot dip aluminised coating considerably increases resistance to oxidation of the first grade and should make possible its use up to temperatures of at least 600 deg. C. (authors) [French] Dans l'optique de leur emploi dans les echangeurs de reacteurs nucleaires des filieres graphite-gaz ou eau lourde-gaz, le comportement en presence de gaz carbonique sous pression d'aciers au chrome-aluminium, contenant jusqu'a 7 pour cent de chrome et 1,5 pour cent d'aluminium a ete etudie entre 400 et 700 deg. C. Les deux nuances les plus interessantes (2 pour cent Cr - 0,35 pour cent Al - 0,35 pour cent Mo et 7 pour cent Cr - 1,5 pour cent Al - 0,6 pour cent Si) restent compatibles avec le gaz carbonique jusqu'a 550 et 600 deg. C respectivement. Un revetement d'aluminium, effectue par immersion dans un bain fondu, ameliore notablement la resistance a l'oxydation de la premiere et doit permettre son empioi jusqu'a 600 deg. C au moins. (auteurs)

Decontamination tests using an electrolytic method on NS 22 S stainless steel discs (1963); Essais de decontamination par voie electrolytique de plaquettes en acier inoxydable NS 22 S (1963)

Energy Technology Data Exchange (ETDEWEB)

Boutot, P; Schipfer, P [Commissariat a l' Energie Atomique, Centre de Production de Plutonium, Marcoule (France). Centre d' Etudes Nucleaires

1963-07-01

These tests were carried out with a view to observing the results obtained by using electrolytic polishing for the decontamination operations. The experimental equipment consists essentially of a current rectifier and adjuster, and of an electrolytic cell fitted with an automatic system for thermal regulation and agitation. The samples made of type NS 22 S stainless steel are contaminated with an active solution of fission products. The activity of the discs is measured before and after each treatment using a bell counter. For each electrolyte, the parameters studied are: - the time, - the reactant concentration, - the temperature, - the current density, - the corrosion. Taking into account the necessity of transforming as little as possible the surface of the part to be treated, the best results are generally obtained using intermediate concentrations of the reactant, low temperatures, and high current densities. (authors) [French] Ces essais ont ete effectues dans le but d'observer les resultats obtenus en utilisant le procede de polissage electrolytique pour les operations de decontamination. Le dispositif experimental consiste essentiellement en un redresseur-variateur de courant et en une cellule electrolytique munie d'un systeme automatique de regulation thermique et d'agitation. Les echantillons en acier inoxydable du type NS 22 S sont contamines par une solution active de produits de fission. L'activite des plaquettes est mesuree avant et apres chaque traitement au moyen d'un compteur cloche. Pour chaque electrolyte, les parametres etudies sont: - le temps, - la concentration du reactif, - la temperature, - la densite de courant, - la corrosion. En tenant compte de la necessite de transformer au minimum l'etat de surface de la piece a traiter, les resultats les meilleurs sont generalement obtenus pour des concentrations moyennes de reactif, des temperatures basses et des densites de courant elevees. (auteurs)

Food irradiation

International Nuclear Information System (INIS)

Luecher, O.

1979-01-01

Limitations of existing preserving methods and possibilities of improved food preservation by application of nuclear energy are explained. The latest state-of-the-art in irradiation technology in individual countries is described and corresponding recommendations of FAO, WHO and IAEA specialists are presented. The Sulzer irradiation equipment for potato sprout blocking is described, the same equipment being suitable also for the treatment of onions, garlic, rice, maize and other cereals. Systems with a higher power degree are needed for fodder preserving irradiation. (author)

Food irradiation

International Nuclear Information System (INIS)

Anon.

1984-01-01

Food preservation by irradiation is one part of Eisenhower's Atoms for Peace program that is enjoying renewed interest. Classified as a food additive by the Food, Drug, and Cosmetic Act of 1958 instead of a processing technique, irradiation lost public acceptance. Experiments have not been done to prove that there are no health hazards from gamma radiation, but there are new pressures to get Food and Drug Administration approval for testing in order to make commercial use of some radioactive wastes. Irradiation causes chemical reactions and nutritional changes, including the destruction of several vitamins, as well as the production of radiolytic products not normally found in food that could have adverse effects. The author concludes that, lacking epidemiological evidence, willing buyers should be able to purchase irradiated food as long as it is properly labeled

Facts about food irradiation: Packaging of irradiated foods

International Nuclear Information System (INIS)

1991-01-01

This fact sheet considers the effects on packaging materials of food irradiation. Extensive research has shown that almost all commonly used food packaging materials toted are suitable for use. Furthermore, many packaging materials are themselves routinely sterilized by irradiation before being used. 2 refs

Cost-benefit analysis of irradiation of vegetables and fruits at the Shanghai irradiation centre

International Nuclear Information System (INIS)

Xu Zhicheng; Sha Zhenyuan

1993-01-01

Differences between the developing and the developed countries in development and application of food irradiation are discussed, including the objectives of irradiation, scale, and the operation and control of facilities. These represent the chief problems of development of food irradiation in the developing countries. A proposal concerning the economic benefit of a gamma irradiation facility is discussed. In the light of many years' operating experience at the Shanghai Irradiation Centre, the operation cost per hour and coefficient of economic benefit are presented. These data can be used to estimate the economic benefit of gamma irradiated products at any time, and are useful for directing the daily operation of gamma irradiation facilities. From examples of cost-benefit analysis of irradiated garlic and apples it is shown that to improve the benefit of gamma irradiation facilities the annual hours of operation must be increased, so as to reduce the cost of operation. Food irradiated with a low dose provides more economic benefit than other irradiated products; the coefficients of economic benefit will increase as the irradiated processing throughput increases. Practical examples are given relating to garlic and apples, showing the economic benefit to wholesalers and retailers. (author). 4 refs, 3 figs, 7 tabs

Detection of irradiated strawberries by identifying ESR peak of irradiated cellulose component

International Nuclear Information System (INIS)

Goto, Michiko; Tanabe, Hiroko

2002-01-01

The method of detecting low-dose irradiated strawberries by identifying ESR peak of irradiated cellulose component was studied. Ratio of peak height (S) of high magnetic field cellulose component, and noise width (N) of either irradiated or unirradiated seeds of strawberries were compared. In this study, sample was identified to be irradiated when S/N ratio of ESR spectrum of 4 min. sweep time was above 0.7. In the case of S/N ratio below 0.7, when the S/N ratio of integrated ESR spectrum, obtained from measuring 10 times with 1 min. sweep time was above 1.0, the sample was identified to be irradiated. The result suggests that S/N ratio is a good marker to detect the irradiation. The strawberries irradiated above 0.5kGy was able to be detected after 3 days storage at room temperature, after 21 days refrigeration and after 60 days freezing, respectively. (author)

Irradiation and Post-Irradiation Storage of Chicken: Effects on Fat and Proteins

International Nuclear Information System (INIS)

Abou-Tarboush, H.M.; Al-Kahtani, H.A.; Abou-Arab, A.A.; Atia, M.; Bajaber, A.S.; Ahmed, M.A.; El-Mojaddidi, M.A.

1997-01-01

Chicken were subjected to gamma irradiation doses of 2.5, 5.0, 7.5 and 10.0 KGy and post-irradiation storage of 21 days at 4±2º. The effects on fat and protein of chicken were studied. Rate of formation of total volatile basic-nitrogen was less in irradiated samples particularly in samples treated with 5.0KGy during the entire storage. Fatty acid profiles of chicken lipids were not significantly (P≤ 0.05) affected by irradiation especially at doses of 5.0 KGy. However, irradiation caused a large increase in thiobarbituric acid (TBA) values which continued gradually during storage. Changes in amino acids were minimal. Irradiated and unirradiated samples showed the appearance of protein subunits with molecular weights in the range of 10.0 to 88.0 and 10.0 to 67.0 KD, respectively. No changes were observed in the sarcoplasmic protein but the intensity of bands in all irradiated samples decreased after 21 days of storage

Food irradiation: fiction and reality

International Nuclear Information System (INIS)

1991-01-01

The International Consultative Group on Food Irradiation (IGCFI), sponsored by World Health Organization (WHO), Food and Agriculture Organization (FAO) and the International Atomic Energy Agency (IAEA), with the intention to provide to governments, especially those of developing countries, scientifically correct information about food irradiation, decided to organize a file and questions of general public interest. The document is composed by descriptive files related with the actual situation and future prospective, technical and scientific terms, food irradiation and the radioactivity, chemical transformations in irradiated food, genetic studies, microbiological safety of irradiated food, irradiation and harmlessness, irradiation and additives, packing, irradiation facilities control, process control, irradiation costs and benefits as well as consumers reaction

Irradiation of food

International Nuclear Information System (INIS)

Lindell, B.; Danielsson-Tham, M.L.; Hoel, C.

1983-01-01

A committee has on instructions from the swedish government made an inquiry into the possible effects on health and working environment from irradition of food. In this report, a review is presented on the known positiv and negative effects of food irradiation Costs, availabilty, shelf life and quality of irradiated food are also discussed. According to the report, the production of radiolysis products during irradiation is not easily evaluated. The health risks from irradiation of spices are estimated to be lower than the risks associated with the ethenoxid treatment presently used. (L.E.)

Facts about food irradiation: Food irradiation costs

International Nuclear Information System (INIS)

1991-01-01

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 also bring consumer benefits in terms of availability, storage life and improved hygiene. 2 refs

Facts about food irradiation: Nutritional quality of irradiated foods

International Nuclear Information System (INIS)

1991-01-01

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

Saturation behavior of irradiation hardening in F82H irradiated in the HFIR

Energy Technology Data Exchange (ETDEWEB)

Hirose, T. [Blanket Engineering Group, Japan Atomic Energy Agency, Naka, Ibaraki (Japan); Shiba, K.; Tanigawa, H.; Ando, M. [Japan Atomic Energy Agency, Tokai-mura, Naga-gun, Ibaraki-ken (Japan); Klueh, R.L. [Oak Ridge National Laboratory, TN (United States); Stoller, R. [ORNL - Oak Ridge National Laboratory, Materials Science and Technology Div., Oak Ridge, AK TN (United States)

2007-07-01

Full text of publication follows: Post irradiation tensile tests on reduced activation ferritic/martensitic steel, F82H have been conducted over the past two decades using Japan Materials Testing Reactor (JMTR) of JAEA, and Fast Flux Testing Facility (FFTF) of PNNL and High Flux Isotope Reactor (HFIR) of ORNL, USA, under Japan/US collaboration programs. According to these results, F82H does not demonstrate irradiation hardening above 673 K up to 60 dpa. The current study has been concentrated on hardening behavior at temperature around 573 K. A series of low temperature irradiation experiment has been conducted at the HFIR under the international collaborative research between JAEA/US-DOE. In this collaboration, the irradiation condition is precisely controlled by the well matured capsule designing and instrumentation. This paper summarizes recent results of the irradiation experiments focused on F82H and its modified steels compared with the irradiation properties database on F82H. Post irradiation tensile tests have been conducted on the F82H and its modified steels irradiated at 573 K and the dose level was up to 25 dpa. According to these results, irradiation hardening of F82H is saturated by 9 dpa and the as-irradiated 0.2 % proof stress is less than 1 GPa at ambient temperature. The deterioration of total elongation was also saturated by 9 dpa irradiation. The ductility of some modified steels which showed larger total elongation than that of F82H before irradiation become the same level as that of standard F82H steel after irradiation, even though its magnitude of irradiation hardening is smaller than that of F82H. This suggests that the more ductile steel demonstrates the more ductility loss at this temperature, regardless to the hardening level. The difference in ductility loss behavior between various tensile specimens will be discussed as the ductility could depend on the specimen dimension. (authors)

16-rod-bundle: Irradiation in the MZFR and post-irradiation examinations

International Nuclear Information System (INIS)

Manzel, R.

1979-04-01

In the course of the irradiation of a 16-rod prototype bundle, the basis has been established for the irradiation of experimental fuel assemblies containing full-length PWR fuel rods in standard positions of the MZFR. The prototype bundle was discharged after an irradiation time of 284 full power days and a burnup of 11400 MWd/tU. The overall performance of the prototype bundle was highly satisfactory. Detailed post-irradiation examinations confirmed the good conditions of bundle structures and fuel rods. (orig.) [de

Mechanical properties of irradiated and non-irradiated Zr1%Nb and Zircaloy claddings

International Nuclear Information System (INIS)

Griger, Agnes

2004-01-01

The mechanical properties of irradiated and non-irradiated Zr1%Nb were determined and they were compared with the analogous properties of Zircaloy-4 to establish connections between the evolution of mechanical parameters of Zr1%Nb and Zircaloy-4 cladding materials and the measure of irradiation. Samples were irradiated in the vertical channels of the Budapest Research Reactor for different time periods at 50-65 C temperature. The measure of irradiation (fluent) for different samples was estimated by means of flux measurement and using the effective irradiation time. Post irradiation uniaxial tension tests in transverse direction were carried out on ring specimens. The mechanical parameters of the Zr1%Nb alloy significantly improve due to the effect of irradiation. However, the values of mechanical parameters do not further increase when the fluent increases above 10 20 n/cm 2 . These results are in good accordance with the Russian ones [1]. Contrary to the behaviour of Zr1%Nb alloy, the mechanical parameters of the Zircaloy practically do not change on the effect of irradiation. The originally high values of ultimate tensile strength and yield stress change only slightly with the increasing fluent in the investigated fluent-region. (Author)

Irradiation enhanced diffusion and irradiation creep tests in stainless steel alloys

International Nuclear Information System (INIS)

Loelgen, R.H.; Cundy, M.R.; Schuele, W.

1977-01-01

A review is given of investigations on the rate of phase changes during neutron and electron irradiation in many different fcc alloys showing either precipitation or ordering. The diffusion rate was determined as a function of the irradiation flux, the irradiation temperature and the irradiation dose. It was found that the radiation enhanced diffusion in all the investigated alloys is nearly temperature independent and linearly dependent on the flux. From these results conclusions were drawn concerning the properties of point defects and diffusion mechanisms rate determining during irradiation, which appears to be of a common nature for fcc alloys having a similar structure to those investigated. It has been recognized that the same dependencies which are found for the diffusion rate were also observed for the irradiation creep rate in stainless steels, as reported in literature. On the basis of this obervation a combination of measurements is suggested, of radiation enhanced diffusion and radiation enhanced creep in stainless steel alloys. Measurements of radiation enhanced diffusion are less time consuming and expensive than irradiation creep tests and information on this property can be obtained rather quickly, prior to the selection of stainless steel alloys for creep tests. In order to investigate irradiation creep on many samples at a time two special rigs were developed which are distinguished only by the mode of stress applied to the steel specimens. Finally, a few uniaxial tensile creep tests will be performed in fully instrumented rigs. (Auth.)

Food irradiation

International Nuclear Information System (INIS)

Hetherington, M.

1989-01-01

This popular-level article emphasizes that the ultimate health effects of irradiated food products are unknown. They may include vitamin loss, contamination of food by botulism bacteria, mutations in bacteria, increased production of aflatoxins, changes in food, carcinogenesis from unknown causes, presence of miscellaneous harmful chemicals, and the lack of a way of for a consumer to detect irradiated food. It is claimed that the nuclear industry is applying pressure on the Canadian government to relax labeling requirements on packages of irradiated food in order to find a market for its otherwise unnecessary products

Irradiation Facilities at CERN

CERN Document Server

Gkotse, Blerina; Carbonez, Pierre; Danzeca, Salvatore; Fabich, Adrian; Garcia, Alia, Ruben; Glaser, Maurice; Gorine, Georgi; Jaekel, Martin, Richard; Mateu,Suau, Isidre; Pezzullo, Giuseppe; Pozzi, Fabio; Ravotti, Federico; Silari, Marco; Tali, Maris

2017-01-01

CERN provides unique irradiation facilities for applications in many scientific fields. This paper summarizes the facilities currently operating for proton, gamma, mixed-field and electron irradiations, including their main usage, characteristics and information about their operation. The new CERN irradiation facilities database is also presented. This includes not only CERN facilities but also irradiation facilities available worldwide.

Isolation of chlamydia in irradiated and non-irradiated McCoy cells

International Nuclear Information System (INIS)

Johnson, L.; Harper, I.A.

1975-01-01

Specimens from eye and genital tract were cultured in parallel in irradiated and non-irradiated McCoy cells and the frequency of isolation of chlamydia using these culture methods was compared. There was a significant difference between the frequencies of isolation; irradiated McCoy cells produced a greater number of positive results. (author)

Study of inclusions and segregation in metals by autoradiography; Etude autoradiographic des inclusions et de la segregation dans les metaux; Izuchenie primesej i usadki metalla s pomoshch'yu avtoradiografii; Estudio autoradiografico de las inclusiones y de la segregacion en los metales

Energy Technology Data Exchange (ETDEWEB)

Makin, S M [Wantage Research Laboratory, Wantage, Berks (United Kingdom)

1962-01-15

Three applications of radioisotope techniques to metallurgy are described. During the course of this work, new autoradiographic techniques are developed. These include the irradiation and autoradiography of extraction replicas, similar to those used in electron microscopy, and a two-colour dye-transfer process in which colour prints of autoradiographs are shown with the corresponding micrographs superposed. These methods are applied to the study of inclusions in steel and uranium and to an investigation of the segregation of sulphur and phosphorus in welds in stainless steel. (author) [French] Le memoire decrit trois applications des radioisotopes en metallurgie. Au cours de ces travaux, l'auteur a mis au point de nouvelles techniques d'autoradiographie. Celles-ci comportent l'irradiation d'empreintes pour autoradiographie et d'empreintes d'extraction, semblables a celles qui sont employees dans la microscopie electronique, et font appel a un procede de transfert en deux couleurs dans lequel on superpose des autoradiographies en couleur et les microphotographies correspondantes. Ces methodes sont appliquees a l'etude des inclusions dans l'acier et l'uranium ainsi qu'aux recherches sur la segregation du soufre et du phosphore dans les pieces soudees en acier inoxydable. (author) [Spanish] Se describen tres aplicaciones de las tecnicas de los radioisotopes en la metalurgia. En el curso de los experimentos se han perfeccionado nuevas tecnicas autorradiograficas, que comprenden la irradiacion de replicas de autorradiografia y extraccion, analogas a las utilizadas en la microscopia electronica y un procedimiento de impresion a dos colores que permite obtener autorradiografias superpuestas a las correspondientes micrografias. Estos metodos se aplican al estudio de inclusiones en el acero y el uranio y a una investigacion de la segregacion del azufre y del fosforo en soldaduras hechas en acero inoxidable. (author) [Russian] Daetsya opisanie trekh sposobov primeneniya

Rhéologie des alliages de fer pur. Lois de comportement a chaud avec recristallisation dynamique

OpenAIRE

Belkebir , Abdellah

1994-01-01

pas de résumé en anglais; Le comportement rhéologique des aciers, élabores a partir de fer de haute pureté, a été caractérisé par compression a chaud. Pour mettre en évidence l'influence individuelle ou conjointe des phénomènes de ségrégation et de précipitation, trois nuances d'acier ont été étudiées. L'influence de la vitesse et de la température de déformation sur le comportement de ces alliages a été examinée a travers les variations des paramètres rhéologiques (coefficient de sensibilité...

HRB-22 capsule irradiation test for HTGR fuel. JAERI/USDOE collaborative irradiation test

Energy Technology Data Exchange (ETDEWEB)

Minato, Kazuo; Sawa, Kazuhiro; Fukuda, Kousaku [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment; and others

1998-03-01

As a JAERI/USDOE collaborative irradiation test for high-temperature gas-cooled reactor fuel, JAERI fuel compacts were irradiated in the HRB-22 irradiation capsule in the High Flux Isotope Reactor at the Oak Ridge National Laboratory (ORNL). Postirradiation examinations also were performed at ORNL. This report describes 1) the preirradiation characterization of the irradiation samples of annular-shaped fuel compacts containing the Triso-coated fuel particles, 2) the irradiation conditions and fission gas releases during the irradiation to measure the performance of the coated particle fuel, 3) the postirradiation examinations of the disassembled capsule involving visual inspection, metrology, ceramography and gamma-ray spectrometry of the samples, and 4) the accident condition tests on the irradiated fuels at 1600 to 1800degC to obtain information about fuel performance and fission product release behavior under accident conditions. (author)

Radiation therapy in leukemia (total body irradiation excluded); Irradiations pour leucemie a l`exclusion de l`irradiation corporelle totale

Energy Technology Data Exchange (ETDEWEB)

Peiffert, D.; Hoffstetter, S. [Centre Alexis-Vautrin, 54 - Vandoeuvre-les-Nancy (France). Dept. de Radiotherapie

1999-03-01

Radiation techniques and indications in leukemias have been described in detail, yet prophylactic cranial irradiation in acute leukemia still has few indications. Cerebrospinal and testicular irradiation are reserved for relapsing disease. Radiation usually results in rapid functional improvement when used in neurologic emergencies and symptomatic neurologic or gross tumors relapses. Nevertheless, the improvements recently obtained by systemic chemotherapy have resulted in the reduction in the use of irradiation, especially in children, where it was considered deleterious with neuropsychological sequelae. Splenic irradiation remains useful for symptomatic myelo-proliferative syndrome. (authors)

Planning of irradiation

Energy Technology Data Exchange (ETDEWEB)

Caha, A; Krystof, V [Vyzkumny Ustav Klinicke a Experimentalni Onkologie, Brno (Czechoslovakia)

1979-07-01

The principles are discussed of the planning of irradiation, ie., the use of the various methods of location of a pathological focus and the possibility of semiautomatic transmission of the obtained data on a two-dimensional or spatial model. An efficient equipment is proposed for large irradiation centres which should cooperate with smaller irradiation departments for which also a range of apparatus is proposed. Irradiation planning currently applied at the Research Institute of Clinical and Experimental Oncology in Brno is described. In conclusion, some of the construction principles of semi-automatic operation of radiotherapy departments are discussed.

Economics of gamma irradiation processing

International Nuclear Information System (INIS)

Tani, Toshio

1980-01-01

The gamma-ray irradiation business started at the Takasaki Laboratory of Japan Atomic Energy Research Institute. The irradiation facilities were constructed thereafter at various sites. The facilities must accept various types of irradiation, and must be constructed as multi-purpose facilities. The cost of irradiation consists of the cost of gamma sources, construction expense, personnel expense, management expense, and bank interest. Most of the expenses are considered to be fixed expense, and the amount of irradiation treatment decides the original costs of work. The relation between the irradiation dose and the construction expense shows the larger facility is more economical. The increase of amount of treatment reduces the original cost. The utilization efficiency becomes important when the amount of treatment and the source intensity exceed some values. The principal subjects of gamma-ray irradiation business are the sterilization of medical tools and foods for aseptic animals, the improvement of quality of plastic goods, and the irradiation of foods. Among them, the most important subject is the sterilization of medical tools. The cost of gamma irradiation per m 3 in still more expensive than that by ethylene oxide gas sterilization. However, the demand of gamma-ray irradiation is increasing. For the improvement of quality of plastic goods, electron irradiation is more favourable than the gamma irradiation. In near future, the economical balance of gamma irradiation can be achieved. (Kato, T.)

Development of irradiation rig in HTTR and dosimetry method. I-I type irradiation equipment

Energy Technology Data Exchange (ETDEWEB)

Shibata, Taiju; Kikuchi, Takayuki [Japan Atomic Energy Research Inst., Oarai, Ibaraki (Japan). Oarai Research Establishment; Miyamoto, Satoshi; Ogura, Kazutomo [Japan Atomic Power Co., Tokyo (Japan)

2002-12-01

The High Temperature Engineering Test Reactor (HTTR) is a graphite-moderated, helium gas-cooled test reactor with a maximum power of 30 MW. The HTTR aims not only to establish and upgrade the technological basis for the HTGRs but also to perform the innovative basic research on high temperature engineering with high temperature irradiation fields. It is planned that the HTTR is used to perform various engineering tests such as the safety demonstration test, high temperature test operation and irradiation test with large irradiation fields at high temperatures. This paper describes the design of the I-I type irradiation equipment developed as the first irradiation rig for the HTTR and does the planned dosimetry method at the first irradiation test. It was developed to perform in-pile creep test on a stainless steel with large standard size specimens in the HTTR. It can give great loads on the specimens stably and can control the irradiation temperature precisely. The in-core creep properties on the specimens are measured by newly developed differential transformers and the irradiation condition in the core is monitored by thermocouples and self-powered neutron detectors (SPNDs), continuously. The irradiated neutron fluence is assessed by neutron fluence monitors of small metallic wires after the irradiation. The obtained data at the first irradiation test can strongly be contributed to upgrade the technological basis for the HTGRs, since it is the first direct measurement of the in-core irradiation environments of the HTTR. (author)

Advanced disassembling technique of irradiated driver fuel assembly for continuous irradiation of fuel pins

International Nuclear Information System (INIS)

Ichikawa, Shoichi; Haga, Hiroyuki; Katsuyama, Kozo; Maeda, Koji; Nishinoiri, Kenji

2012-01-01

It was necessary to carry out continuous irradiation tests in order to obtain the irradiation data of high burn-up fuel and high neutron dose material for FaCT (Fast Reactor Cycle Technology Development) project. There, the disassembling technique of an irradiated fuel assembly was advanced in order to realize further continuous irradiation tests. Although the conventional disassembling technique had been cutting a lower end-plug of a fuel pin needed to fix fuel pins to an irradiation vehicle, the advanced disassembling technique did not need cutting a lower end-plug. As a result, it was possible to supply many irradiated fuel pins to various continuous irradiation tests for FaCT project. (author)

Food irradiation: Activities and potentialities

Science.gov (United States)

Doellstaedt, R.; Huebner, G.

After the acceptance of food irradiation up to an overall average dose of 10 kGy recommended by the Joint FAO/IAEA/WHO Expert Committee on the Wholesomeness of Irradiated Food in October 1980, the G.D.R. started a programme for the development of techniques for food irradiation. A special onion irradiator was designed and built as a pilot plant for studying technological and economic parameters of the irradiation of onions. The new principle of bulk-cargo irradiation allows the integration of this technology into the usual harvest technology for onions on the way from field to storage. Scientific and applied research work has been carried out in the past 3 yr on the irradiation of spices, potatoes, eviscerated chicken, animal feeds, fodder yeast, drugs and vaccines. In connection with the irradiation of eviscerated chicken, fodder yeast and animal feeds the basis of an antisalmonella programme has been discussed. Germ-count-reduced spices were employed for the production of test charges of preserves and tinned products. The results have led to the decision to design and build a new multipurpose irradiator for food irradiation. In order to cover the legal aspects of food irradiation the Ministry of Health issued regulations concerning the recommendation of irradiated food in the G.D.R.

Food Irradiation in Japan

Energy Technology Data Exchange (ETDEWEB)

Kawabata, T.

1981-09-15

Since 1967 research activities on food irradiation in Japan have been carried out under the National Food Irradiation Programme by the Japanese Atomic Energy Commission. The programme has been concentrated on the technological and economical feasibility and wholesomeness testings of seven irradiated food items of economic importance to the country, i.e. potatoes, onions, wheat, rice, 'kamaboko' (fish-paste products), 'Vienna' sausages and mandarin oranges. By now most studies, including wholesomeness testings of these irradiated food items, have been completed. In Japan, all foods or food additives for sale are regulated by the Food Sanitation Law enforced in 1947. Based on studies made by the national programme, irradiated potatoes were given 'unconditional acceptance' for human consumption in 1972. At present, irradiated potatoes are the only food item which has so far been approved by the Minister of Health and Welfare. Unless the Minister of Health and Welfare has declared that items are not harmful to human health on obtaining comments from the Food Sanitation Investigation Council, no irradiated food can be processed or sold. In addition, the import of irradiated foodstuffs other than potatoes from foreign countries is prohibited by law.

Irradiated foods and allergy. From a perspective of irradiation chemistry of proteins

International Nuclear Information System (INIS)

Miyahara, Makoto

2003-01-01

A change of protein in irradiated food has been known. There are a few reports on change of allergy of irradiated foods. Two kinds of allergy such as the immediate allergy (I type) and delayed allergy (IV type) are taken ill by foods. I type is related to irradiated foods. Allergen enters body through digestive tract. Anti body (IgE) is protein with from 10,000 to 100,000 molecular weight. Allergic disease is originated mainly by egg, milk, wheat, buckwheat, peanut and shrimp. When food is irradiated, the proteins are decomposed and produced higher and lower molecular compounds at the same time. Change of the viscosity and the sedimentation coefficient and deactivation of enzymes of β-lactoglobulin, cow albumin, egg albumin and casein were investigated. There is no report of increasing allergy by irradiation. However, some paper indicated that immunogenicity of protein was decreased by irradiation. (S.Y.)

Development of food irradiation technology and consumer attitude toward irradiated food in Korea

International Nuclear Information System (INIS)

Kwon, Joong-Ho; Byun, Myung-Woo; Cho, Han-Ok

1992-01-01

In Korea, the well-integrated research of biological effects of radiation has been launched from the late 1960s. As research activities, the following food items have been dealt with: sprouting foods, fruits, mushrooms, grains, spices or mixed condiments, fish or fishery products, meat or meat products, and fermented foods. The usage of gamma radiation from 60 Co source is now authorized for food irradiation of the following items: potato, onion, garlic, chestnut, mushroom, dried mushroom, dried spices (including red pepper, garlic, black pepper, onion, ginger, and green onion), dried meat, powdered fish and shellfish, soybean paste powder, hot pepper paste powder, soybean sauce powder, and starch. Since the authorization of food irradiation in 1985, consumers' acceptance has been considered the most important. The survey evaluating the basic perception and attitule toward food irradiation revealed the following results. Consumers' awareness of food irradiation was 82%, with significantly higher in radiation workers than the general public (p<0.0001). Seventy-five percent distinguished the contaminated food by radionuclides from irradiated food. In purchasing irradiated foods, 50.9% required more information. The contribution of irradiated foods to wholesomeness was suspicious in 51%, acceptable in 33%, and uncertain in 16%. If information about the benefits of irradiation is provided to consumers, positive response was increased to 60%. The most critical impediment in the commercial application of food irradiation was found to have resulted from the general consumers' slow acceptance; however, consumers' attitude to irradiated food became positive if they understood the safety and advantages of this technology. The most important task is to overcome consumers' psychological resistance and transporting matters of the products to be irradiated. (N.K.)

Development of detection methods for irradiated foods; development of immunological identification of irradiated foods

Energy Technology Data Exchange (ETDEWEB)

Lee, Kyong Ae; Lee, Yoon Jin; Choi, Yoon Jung; Han, Su Kyong [Soonchunhyang University, Asan (Korea)

2002-04-01

Enzyme-linked Immunosorbent assay systems for the identification of irradiated egg, pork and chicken was developed. Eggs were irradiated in their shells to 0.5{approx}7kGy. Pork was irradiated to 0.5{approx}3kGy and chicken irradiated to 0.5kGy{approx}5kGy. The most sensitive proteins to irradiation were screened by SDS-PAGE and purified. Ovalbumin from egg, salt soluble protein(p) from pork, and salt soluble protein(c) from chicken showed the most sensitivity to irradiation. To investigate for a practical use in identifying of irradiated egg, pork and chicken, competitive ELISA was performed. The binding activity of ovalbumin to anti-ovalbumin IgG was reduced in a dose-dependent manner by irradiating up to 7kGy, and considerably lowered after irradiating at 7kGy. The concentration of 50% inhibition of ovalbumin to IgG was increased to 1.5(0.5kGy){approx}3.7(7kGy) times in an dose-dependent relationship. The binding activity of salt soluble protein(p) to anti-salt soluble protein IgG (anti-SSPp IgG)was also reduced in a dose-dependent manner by irradiating up to 3kGy, and considerably lowered after irradiating at 3kGy. The concentration of 50% inhibition of salt soluble protein to IgG was increased to 1.1(0.5kGy){approx}5.2(3kGy) times in a dose-dependent relationship. On the other hand, the binding activity of salt soluble protein(c) to anti-salt soluble protein IgG(anti-SSPc IgG) was reduced in a dose-dependent manner by irradiating up to 5kGy, too, and considerably lowered after irradiating at 5kGy. The concentration of 50% inhibition of salt soluble protein to IgG was increased to 1.1{approx}2.3 times in a dose-dependent relationship. SDS-PAGE of the irradiation sensitive proteins showed the partial breakdown of it was induced by irradiation. So, the lowering of binding activity was probably due to the partial breakdown of ovalbumin by irradiation. 25 refs., 12 figs., 5 tabs. (Author)

Irradiation of onions with the commercial potato irradiator

International Nuclear Information System (INIS)

Aoki, Shohei; Kawashima, Koji; Hayasi, Toru

1983-01-01

Three varieties of onion harvested in Hokkaido were irradiated with the Shohoro Potato Irradiator on 29th September, 1981. One ton of each of the varieties, Kitamiki (KI), Ohohtsuku (OH) and Furanui (FU), was used in this investigation. Onions had longer dormancy period in the order of FU>OH>KI. Higher sprouting percentage was obtained in the unirradiated onions, while they were stored at a higher temperature or stored for a longer period. Generally, unirradiated onions sprouted before they were deteriorated. Thus the number of deteriorated bulbs in the unirradiated onions was superficially less than that in the irradiated ones. When the onions which were taken from warehouses on 26th March, 1982 were stored at room temperature, the percentage of wholesome bulbs was higher in KI and OH than FU. Small buds in some of the irradiated onions turned dark after a long storage time. Quantitative estimation of this phenomena is left to be resolved. There was little relationship between the weight loss and the number of wholesome onions. (author)

Irradiation of goods

International Nuclear Information System (INIS)

Lunt, R.E.

1987-01-01

Mechanical handling apparatus is adapted to handle goods, such as boxed fruit, during a process of irradiation, in palletized form. Palletized goods are loaded onto wheeled vehicles in a loading zone. Four vehicles are wheeled on a track into an irradiation zone via a door in a concrete shield. The vehicles are arranged in orthogonal relationship around a source of square section. Turntables are positioned at corners of the square shaped rail truck around the source selectively to turn the vehicles to align then with track sections. Mechanical manipulating devices are positioned in the track sections opposed to sides of the source. During irradiation, the vehicles and their palletized goods are cylically moved toward the source to offer first sides of the goods for irradiation and are retraced from the source and are pivoted through 90 0 to persent succeeding sides of the goods for irradiation

Chemical changes after irradiation and post-irradiation storage in tilapia and Spanish mackerel

International Nuclear Information System (INIS)

Al-Kahtani, H.A.; Abu-Tarboush, H.M.; Bajaber, A.S.; Atia, M.; Abou-Arab, A.A.; El-Mojaddidi, M.A.

1996-01-01

Influence of gamma irradiation (1.5-10 kGy) and post-irradiation storage up to 20 days at 2 +/- 2 degrees C on some chemical criteria of tilapia and spanish mackerel were studied. Total volatile basic nitrogen formation was lower in irradiated fish than in the unirradiated. Irradiation also caused a larger increase in thiobarbituric acid values which continued gradually during storage. Some fatty acids decreased by irradiation treatments at all doses. Thiamin loss was more severe at higher doses (greater than or equal to 4.5 kGy), whereas riboflavin was not affected. Alpha and gamma tocopherols of tilapia and alpha, beta, gamma, and delta tocopherols, in Spanish mackerel, decreased with increased dose and continued to decrease during 20-day post-irradiation storage

Compatibility problems of canning materials with carbon dioxide at high temperatures; Problemes de comptabilite des materiaux de gainage avec le gaz carbonique aux temperatures elevees

Energy Technology Data Exchange (ETDEWEB)

Darras, R; Loriers, H [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

1964-07-01

and iron-aluminium alloys should increase as a result of the research carried out with a view to improving their technological and mechanical properties. (authors) [French] L'adoption, en France, du gaz carbonique sous pression comme fluide caloporteur dans les reacteurs avances des filieres graphite-gaz et eau lourde-gaz, a impose la recherche de materiaux de gainage susceptibilite prendre la releve des alliages de magnesium. En effet, ces derniers deviennent inutilisables au dessus de 500 C environ, en raison de la proximite de leur point de fusion et de leurs proprietes mecaniques alors defaillantes, quoique leur compatibilite avec le gaz carbonique reste relativement bonne. Le beryllium, particulierement seduisant en raison de sa faible section de capture pour les neutrons thermiques, presente, entre autres, un inconvenient grave: son utilisation dans le gaz carbonique n'est possible, des 600 C, que si ce gaz est rigoureusement desseche, la pression partielle de vapeur d'eau etant le facteur determinant imposant une dessication d'autant plus poussee que la pression nominale est plus elevee. Dans le cas contraire, apres une courte periode d'incubation, l'oxydation s'accelere, conduisant a une corrosion intergranulaire rapidement destructrice. Neanmoins, les alliages beryllium-calcium ou beryllium-magnesium, a 0,5 pour cent environ d'element d'addition, permettent de surmonter cette difficulte; ils restent utilisables en presence de quelques centaines de vpm de vapeur d'eau jusqu'a 700 C au moins. Les problemes metallurgiques lies a la mise en oeuvre du beryllium ou de ses alliages ont cependant conduit a envisager provisoirement l'utilisation d'aciers inoxydables austenitiques. Ces materiaux sont intrinsequement tres resistants a l'oxydation; mais, comme ils ne peuvent etre employes qu'en faible epaisseur, etant donne leur section de capture importante, il y a lieu de choisir les nuances comparativement les moins oxydables. Au dessus de 600 C, les nuances

New facility for post irradiation examination of neutron irradiated beryllium

International Nuclear Information System (INIS)

Ishitsuka, Etsuo; Kawamura, Hiroshi

1995-01-01

Beryllium is expected as a neutron multiplier and plasma facing materials in the fusion reactor, and the neutron irradiation data on properties of beryllium up to 800 degrees C need for the engineering design. The acquisition of data on the tritium behavior, swelling, thermal and mechanical properties are first priority in ITER design. Facility for the post irradiation examination of neutron irradiated beryllium was constructed in the hot laboratory of Japan Materials Testing Reactor to get the engineering design data mentioned above. This facility consist of the four glove boxes, dry air supplier, tritium monitoring and removal system, storage box of neutron irradiated samples. Beryllium handling are restricted by the amount of tritium;7.4 GBq/day and 60 Co;7.4 MBq/day

Gamma irradiation devices

International Nuclear Information System (INIS)

Foeldiak, Gabor; Stenger, Vilmos.

1983-01-01

The main parameters and the preparation procedures of the gamma radiation sources frequently applied for irradiation purposes are discussed. In addition to 60 Co and 137 Cs sources also the nuclear power plants offer further opportunities: spent fuel elements and products of certain (n,γ) reactions can serve as irradiation sources. Laboratory scale equipments, pilot plant facilities for batch or continuous operation, continuous industrial irradiators and special multipurpose, mobile and panorama type facilities are reviewed including those in Canada, USA, India, the Soviet Union, Hungary, UK, Japan and Australia. For irradiator design the source geometry dependence of the spatial distribution of dose rates can be calculated. (V.N.)

Parametric relationships for gamma dose and irradiation homogeneity in a sewage sludge irradiator

International Nuclear Information System (INIS)

Krishnamurthy, K.

1986-01-01

A study on the inter-relationships between factors governing γ dose and irradiation homogeneity in a sewage sludge irradiator is presented here. The analysis involves a 60 Co irradiator of cylindrical irradiation geometry with batchwise operation for hygienisation of liquid sludge. The influence of the parameters such as the source-target geometry, strength of 60 Co sources in the irradiator, hygienisation dose and rheological and hydraulic characteristics of sewage sludge on the selection of the three critical factors viz. the pumping rate (P) required to maintain turbulent flow regime in the irradiation zone; the mininum re-circulation time (Tsub(m)) essential to achieve a certain degree of homogeneity of dose absorption in the fluid; and the irradiation time (Tsub(i)) required to impart the necessary dose for the desired hygienisation effect in the sludge has been discussed in detail and inter-relationships among these three factors have been worked out. The applicability of the relationships to a typical operating plant has also been elucidated. (author)

Food irradiation - now

International Nuclear Information System (INIS)

Basson, R.A.

1989-01-01

Food irradiation technology in South Africa is about to take its rightful place next to existing food preservation methods in protecting food supplies. This is as a result of several factors, the most important of which is the decision by the Department of Health and Population Development to introduce compulsory labelling of food irradiation. The factors influencing food irradiation technology in South Africa are discussed

Facts about food irradiation: Irradiation and food safety

International Nuclear Information System (INIS)

1991-01-01

This fact sheet focusses on the question of whether irradiation can be used to make spoiled food good. No food processing procedures can substitute for good hygienic practices, and good manufacturing practices must be followed in the preparation of food whether or not the food is intended for further processing by irradiation or any other means. 3 refs

Irradiated film material and method of the irradiation

International Nuclear Information System (INIS)

1978-01-01

The irradiation of polymer film material is a strengthening procedure. To obtain a substantial uniformity in the radiation dosage profile, the film is irradiated in a trough having lateral deflection blocks adjacent to the film edges. These deflect the electrons towards the surface of the trough bottom for further deflection towards the film edge. (C.F.)

Food irradiation and consumer values

International Nuclear Information System (INIS)

Bruhn, C.M.; Schutz, H.G.; Sommer, R.

1988-01-01

A mail survey technique was used to determine if value hierarchy, locus of control, innovativeness, and demographic parameters could distinguish between subjects expressing different levels of concern and willingness to buy irradiated food. Concern toward irradiated food was lower than concern for other food safety issues, probably because many expressed uncertainty regarding irradiation. Those ranking the value “an ecologically balanced world” expressed the greatest irradiation concern. Factors which could predict high irradiation concern were being highly concerned about the use of chemical sprays on food, completing more formal education and being female; those believing that life was controlled by luck were less concerned. Irradiation concern was a principal factor determining willingness to buy irradiated foods. Innovative consumers were more likely to try irradiated foods than noninnovative. Implications for consumer education are presented

Irradiation, annealing, and reirradiation research in the ORNL heavy-section steel irradiation program

International Nuclear Information System (INIS)

Nanstad, R.K.; Iskander, S.K.; McCabe, D.E.; Sokolov, M.A.

1997-01-01

One of the options to mitigate the effects of irradiation on reactor pressure vessels (RPV) is to thermally anneal them to restore the toughness properties that have been degraded by neutron irradiation. This paper summarizes experimental results from work performed as part of the Heavy-Section Steel Irradiation (HSSI) Program managed by Oak Ridge National Laboratory (ORNL) for the U.S. Nuclear Regulatory Commission. The HSSI Program focuses on annealing and re-embrittlement response of materials which are representative of those in commercial RPVs and which are considered to be radiation-sensitive. Experimental studies include (1) the annealing of materials in the existing inventory of previously irradiated materials, (2) reirradiation of previously irradiated/annealed materials in a collaborative program with the University of California, Santa Barbara (UCSB), (3) irradiation/annealing/reirradiation of U.S. and Russian materials in a cooperative program with the Russian Research Center-Kurchatov Institute (RRC-KI), (4) the design and fabrication of an irradiation/anneal/reirradiation capsule and facility for operation at the University of Michigan Ford Reactor, (5) the investigation of potential for irradiation-and/or thermal-induced temper embrittlement in heat-affected zones (HAZs) of RPV steels due to phosphorous segregation at grain boundaries, and (6) investigation of the relationship between Charpy impact toughness and fracture toughness under all conditions of irradiation, annealing, and reirradiation

Food irradiation makes progress

International Nuclear Information System (INIS)

Kooij, J. van

1984-01-01

In the past fifteen years, food irradiation processing policies and programmes have been developed both by a number of individual countries, and through projects supported by FAO, IAEA and WHO. These aim at achieving general acceptance and practical implementation of food irradiation through rigorous investigations of its wholesomeness, technological and economic feasibility, and efforts to achieve the unimpeded movement of irradiated foods in international trade. Food irradiation processing has many uses

KEY RESULTS FROM IRRADIATION AND POST-IRRADIATION EXAMINATION OF AGR-1 UCO TRISO FUEL

Energy Technology Data Exchange (ETDEWEB)

Demkowicz, Paul A.; Hunn, John D.; Petti, David A.; Morris, Robert N.

2016-11-01

The AGR-1 irradiation experiment was performed as the first test of tristructural isotropic (TRISO) fuel in the US Advanced Gas Reactor Fuel Development and Qualification Program. The experiment consisted of 72 right cylinder fuel compacts containing approximately 3×105 coated fuel particles with uranium oxide/uranium carbide (UCO) fuel kernels. The fuel was irradiated in the Advanced Test Reactor for a total of 620 effective full power days. Fuel burnup ranged from 11.3 to 19.6% fissions per initial metal atom and time average, volume average irradiation temperatures of the individual compacts ranged from 955 to 1136°C. This paper focuses on key results from the irradiation and post-irradiation examination, which revealed a robust fuel with excellent performance characteristics under the conditions tested and have significantly improved the understanding of UCO coated particle fuel irradiation behavior within the US program. The fuel exhibited a very low incidence of TRISO coating failure during irradiation and post-irradiation safety testing at temperatures up to 1800°C. Advanced PIE methods have allowed particles with SiC coating failure to be isolated and meticulously examined, which has elucidated the specific causes of SiC failure in these specimens. The level of fission product release from the fuel during irradiation and post-irradiation safety testing has been studied in detail. Results indicated very low release of krypton and cesium through intact SiC and modest release of europium and strontium, while also confirming the potential for significant silver release through the coatings depending on irradiation conditions. Focused study of fission products within the coating layers of irradiated particles down to nanometer length scales has provided new insights into fission product transport through the coating layers and the role various fission products may have on coating integrity. The broader implications of these results and the application of

Reactivation of UV- and γ-irradiated herpes virus in UV- and X-irradiated CV-1 cells

International Nuclear Information System (INIS)

Takimoto, K.; Niwa, O.; Sugahara, T.

1982-01-01

Enhanced reactivation of UV- and γ-irradiated herpes virus was investigated by the plaque assay on CV-1 monkey kidney monolayer cells irradiated with UV light or X-rays. Both UV- and X-irradiated CV-1 cells showed enhancement of survival of UV-irradiated virus, while little or no enhancement was detected for γ-irradiated virus assayed on UV- or X-irradiated cells. The enhanced reactivation of UV-irradiated virus was greater when virus infection was delayed 24 or 48 h, than for infection immediately following the irradiation of cells. Thus the UV- or X-irradiated CV-1 cells are able to enhance the repair of UV damaged herpes virus DNA, but not of γ-ray damaged ones. (author)

Ingestion and digestion of erythrocytes by non-irradiated and irradiated macrophages

Energy Technology Data Exchange (ETDEWEB)

Vorbrodt, A; Grabska, A; Krzyzowska-Gruca, S; Gruca, S

1975-01-01

The effect of x rays (1300 R) and gamma irradiation (3000 R) on phagocytic activity of mouse peritoneal macrophages cultivated in vitro was studied using human glutaraldehyde-fixed red blood cells. The peroxidative activity of haemoglobin was cytochemically detected by the DAB method. The obtained results indicate that the applied dose of x irradiation does not affect the phagocytic activity of macrophages. On the contrary, the gamma irradiation (3000 R) causes acceleration of phagocytic activity of macrophages with concomitant impairment of intracellular digestion of ingested material. Weakened cytochemical reaction for acid phosphatase suggests that sufficiently high doses of irradiation cause some disturbances in the biosynthesis of lysosomal enzymes in exposed macrophages.

Irradiation behavior evaluation of oxide dispersion strengthened ferritic steel cladding tubes irradiated in JOYO

Energy Technology Data Exchange (ETDEWEB)

Yamashita, Shinichiro, E-mail: yamashita.shinichiro@jaea.go.jp; Yano, Yasuhide; Ohtsuka, Satoshi; Yoshitake, Tsunemitsu; Kaito, Takeji; Koyama, Shin-ichi; Tanaka, Kenya

2013-11-15

Irradiation behavior of ODS steel cladding tubes was evaluated for the further progress in understanding of the neutron-irradiation effects on ODS steel. Two types of ODS (9Cr–ODS{sub F}/M, 12Cr–ODS{sub F}) steel cladding tubes with differences in basic compositions and matrix phases were irradiated in JOYO. Post-irradiation examination data concerning hardness, ring tensile property, and microstructure were obtained. Hardness measurement after irradiation showed that there was an apparent irradiation temperature dependence on hardness for 9Cr–ODS{sub F}/M steel whereas no distinct temperature dependence for 12Cr–ODS{sub F} steel. Also, there was no significant change in tensile strengths after irradiation below 923 K, but those above 1023 K up to 6.6 × 10{sup 26} n/m{sup 2} (E > 0.1 MeV) were decreased by about 20%. TEM observations showed that the radiation-induced defect cluster formation during irradiation was suppressed because of high density sink site for defect such as initially-existed dislocation, and precipitate interfaces. In addition, oxide particles were stable up to the maximum doses of this irradiation test.

Effect of irradiation spectrum on the microstructure of ion-irradiated Al2O3

International Nuclear Information System (INIS)

Zinkle, S.J.

1994-01-01

Polycrystalline samples of alpha-alumina have been irradiated with various ions ranging from 3.6 MeV Fe + to 1 MeV H + ions at 650 C. Cross-section transmission electron microscopy was used to investigate the depth-dependent microstructure of the irradiated specimens. The microstructure following irradiation was observed to be dependent on the irradiation spectrum. In particular, defect cluster nucleation was effectively suppressed in specimens irradiated with light ions such as 1 MeV H + ions. On the other hand, light ion irradiation tended to accelerate the growth rate of dislocation loops. The microstructural observations are discussed in terms of ionization enhanced diffusion processes

Alloys under irradiation

International Nuclear Information System (INIS)

Martin, G.; Bellon, P.; Soisson, F.

1997-01-01

During the last two decades, some effort has been devoted to establishing a phenomenology for alloys under irradiation. Theoretically, the effects of the defect supersaturation, sustained defect fluxes and ballistic mixing on solid solubility under irradiation can now be formulated in a unified manner, at least for the most simple cases: coherent phase transformations and nearest-neighbor ballistic jumps. Even under such restrictive conditions, several intriguing features documented experimentally can be rationalized, sometimes in a quantitative manner and simple qualitative rules for alloy stability as a function of irradiation conditions can be formulated. A quasi-thermodynamic formalism can be proposed for alloys under irradiation. However, this point of view has limits illustrated by recent computer simulations. (orig.)

Preliminary irradiation test results from the Yankee Atomic Electric Company reactor vessel test irradiation program

International Nuclear Information System (INIS)

Biemiller, E.C.; Fyfitch, S.; Campbell, C.A.

1993-01-01

The Yankee Atomic Electric Company test irradiation program was implemented to characterize the irradiation response of representative Yankee Rowe reactor vessel beltline plate materials and to remove uncertainties in the analysis of existing irradiation data on the Yankee Rowe reactor vessel steel. Plate materials each containing 0.24 w/o copper, but different nickel contents at 0.63 w/o and 0.19 w/o, were heat treated to simulate the Yankee vessel heat treatment (austenitized at 1800 deg F) and to simulate Regulatory Guide 1.99 database materials (austenitized at 1600 deg. F). These heat treatments produced different microstructures so the effect of microstructure on irradiation damage sensitivity could be tested. Because the nickel content of the test plates varied and the copper level was constant, the effect of nickel on irradiation embrittlement was also tested. Correlation monitor material, HSST-02, was included in the program to benchmark the Ford Nuclear Reactor (U. of Michigan Test Reactor) which had never been used for this type of irradiation program. Materials taken from plate surface locations (vs. 1/4T) were included to test whether or not the improved toughness properties of the plate surface layer, resulting from the rapid quench, is maintained after irradiation. If the improved properties are maintained, pressurized thermal shock calculations could utilize this margin. Finally, for one experiment, irradiations were conducted at two irradiation temperatures (500 deg. F and 550 deg. F) to determine the effect of irradiation temperature on embrittlement. The preliminary results of the irradiation program show an increase in T 30 shift of 69 deg. F for a decrease in irradiation temperature of 50 deg. F. The results suggest that for nickel bearing steels, the superior toughness of plate surface material is maintained after irradiation and for the copper content tested, nickel had no apparent effect on irradiation response. No apparent microstructure

Some physical properties of irradiated and non-irradiated oxide glasses containing uranium

International Nuclear Information System (INIS)

Simon, V.; Ardelean, I.; Simon, S.; Cozar, O.; Milea, I.; Lupsa, I.; Mih, V.

1995-01-01

The x U O 3 (1-x) [2 P 2 O 5 · Na 2 O] non-irradiated and gamma irradiated glasses (0 3+ , U 4+ and U 5+ ions. The gamma irradiation induces paramagnetic defects around the glass network forming sites occupied by phosphorous atoms. The non-irradiated samples are weak paramagnetic up to x = 0.1. For higher U O 3 concentration (0.1 < x ≤ 0.2) the magnetic measurements indicated a larger number of paramagnetic ions which are magnetically isolated and exhibit a Curie type behaviour. (author) 5 figs., 14 refs

Market Trials of Irradiated Spices

International Nuclear Information System (INIS)

Charoen, Saovapong; Eemsiri, Jaruratana; Sajjabut, Surasak

2009-07-01

Full text: The objectives of the experiment were to disseminate irradiated retail foods to the domestic publics and to test consumer acceptance on irradiated ground chilli and ground pepper. Market trials of irradiated ground chilli and ground pepper were carried out at 2 local markets and 4 in Bangkok and Nontaburi in 2005-2007. Before the start of the experiment, processing room, gamma irradiation room and labels of the products were approved by Food and Drug Administration, Thailand. 50 grams of irradiated products were packaged in plastic bags for the market trials. 688 and 738 bags of ground chilli and ground pepper were sold, respectively. Questionnaires distributed with the products were commented by 59 consumers and statistically analyzed by experimental data pass program. 88.1 and 91.4 percents of the consumers were satisfied with the quality and the price, respectively. 79.7% of the consumers chose to buy irradiated ground chilli and ground pepper because they believed that the quality of irradiated products were better than that of non-irradiated ones. 91.5% of the consumers would certainly buy irradiated chilli and pepper again. Through these market trials, it was found that all of the products were sold out and the majority of the consumers who returned the questionnaires was satisfied with the irradiated ground chilli and ground pepper and also had good attitude toward irradiated foods

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

International Nuclear Information System (INIS)

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

1990-01-01

The shelf-life of packed minced meat has been increased at least threefold at 4 0 C by applying a 2 kGy dose. Results have been confirmed by detailed quantitative microbiological examinations. Sensory evaluations show no significant difference between the unirradiated and irradiated samples. The optimal average dose was 4 kGy for packed-frozen chicken. The number of mesophilic aerobic microbes was reduced by 2, that of psychrotolerant by 2-3 and that of Enterobacteriaceae by 3-4 orders of magnitude by 4 kGy. S. aureus and Salmonella could not be detected in the 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. (author)

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

Energy Technology Data Exchange (ETDEWEB)

Kiss, I.F.; Beczner, J.; Zachariev, Gy. (Central Food Research Inst., Budapest (Hungary)); Kovacs, S. (Veterinary and Food Control Centre, Budapest (Hungary))

1990-01-01

The shelf-life of packed minced meat has been increased at least threefold at 4{sup 0}C by applying a 2 kGy dose. Results have been confirmed by detailed quantitative microbiological examinations. Sensory evaluations show no significant difference between the unirradiated and irradiated samples. The optimal average dose was 4 kGy for packed-frozen chicken. The number of mesophilic aerobic microbes was reduced by 2, that of psychrotolerant by 2-3 and that of Enterobacteriaceae by 3-4 orders of magnitude by 4 kGy. S. aureus and Salmonella could not be detected in the 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. (author).

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

Science.gov (United States)

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

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

Food irradiation 2009

International Nuclear Information System (INIS)

Narvaiz, Patricia

2009-01-01

Food irradiation principles; its main applications, advantages and limitations; wholesomeness, present activities at Ezeiza Atomic Centre; research coordinated by the International Atomic Energy Agency; capacity building; and some aspects on national and international regulations, standards and commercialization are briefly described. At present 56 countries authorize the consumption of varied irradiated foods; trade is performed in 32 countries, with about 200 irradiation facilities. Argentina pioneered nuclear energy knowledge and applications in Latin America, food irradiation included. A steady growth of food industrial volumes treated in two gamma facilities can be observed. Food industry and producers show interest towards new facilities construction. However, a 15 years standstill in incorporating new approvals in the Argentine Alimentary Code, in spite of consecutive request performed either by CNEA or some food industries restricts, a wider industrial implementation, which constitute a drawback to future regional commercialization in areas such as MERCOSUR, where Brazil since 2000 freely authorize food irradiation. Besides, important chances in international trade with developed countries will be missed, like the high fresh fruits and vegetables requirements United States has in counter-season, leading to convenient sale prices. The Argentine food irradiation facilities have been designed and built in the country. Argentina produces Cobalt-60. These capacities, unusual in the world and particularly in Latin America, should be protected and enhanced. Being the irradiation facilities scarce and concentrated nearby Buenos Aires city, the possibilities of commercial application and even research and development are strongly limited for most of the country regions. (author) [es

Consumer acceptance of irradiated foods

International Nuclear Information System (INIS)

Feenstra, M.H.; Scholten, A.H.

1991-01-01

Although the first experiments on food irradiation were carried out in 1916 in Sweden, food irradiation, is for consumers, a relatively new technology. From the sixties food irradiation has been applied more and more, so that the consumer movement has become alert to this technology. Since then a lot of controversies have arisen in the literature about wholesomeness, safety, effects, etc. Food irradiation is currently permitted on a small scale in about 30 countries; in some countries or states food irradiation has been put under a ban (e.g. Australia, New Zealand, New Jersey). The World Health Organization (WHO) and the Food and Agriculture Organization of the United Nations (FAO) have, however, chosen food irradiation as a safe and sound method for preserving and improving the safety of food. Reactions on the part of the consumer organizations of many countries are however not in favour of or are even opposed to food irradiation. In this chapter consumer acceptance related to technological developments is described, then the convergence of the consumer movement on public opinion and concern on food irradiation is discussed. The need for labelling of irradiated food products is discussed and finally recommendations are given of ways to change consumers attitudes to food irradiation. (author)

Food irradiation development in Japan

International Nuclear Information System (INIS)

Kawabata, T.

1981-01-01

In Japan, the first food irradiation research was carried out on the preservation of fish and fishery products. In 1966, the Atomic Energy Commission of the Japanese Government (JAEC) decided to promote the National Project on Food Irradiation and, in 1967, the Steering Committee on food irradiation research in the Atomic Energy Bureau, Science and Technology Agency, selected the following food items as of economic importance to the country, i.e., potatoes, onions, rice, wheat, ''Vienna'' sausage, ''kamaboko'' (fish meat jelly products) and mandarin oranges. The National Project is expected to finish at the end of the 1981 fiscal year. Based on the studies by the National Project, irradiated potatoes were given ''unconditional acceptance'' for human consumption in 1972. Already in 1973, a commercial potato irradiator was built at Shihoro, Hokkaido. In 1980, the Steering Committee submitted a final report on the effectiveness and wholesomeness studies on irradiated onions to the JAEC. This paper gives a brief explanation of the legal aspects of food irradiation in Japan, and the present status of wholesomeness studies on the seven items of irradiated foods. In addition, topics concerning food irradiation research on ''kamaboko'', especially on the effectiveness and a new detecting method for the irradiation treatment of these products, are outlined. (author)

Mechanical Design and Manufacturing Preparation of Loading Unloading Irradiation Facility in Reflector Irradiation Position

International Nuclear Information System (INIS)

Hasibuan, Djaruddin

2004-01-01

Base on planning to increase of the irradiation service quality in Multi purpose Reactor-GAS, the mechanical design and manufacturing of the (n,γ) irradiation facility has been done. The designed of (n,γ) irradiation facility is a new facility in Multi purpose Reactor-GAS. The design doing by design of stringer, guide bar and hanger. By the design installation, the continuous irradiation service of non fission reaction will be easy to be done without reactor shut down. The design of the facility needs 3 pieces Al pipe by 36 x 1.5 mm, a peace of Al round bar by 80 mm diameter and a piece of Al plate by 20 x 60 x 0.2 mm for the stringer and guide bar manufacturing. By the building of non fission irradiation facility in the reflector irradiation position, will make the irradiation service to be increased. (author)

Irradiation sequels of retinoblastomas. Sequelles de l'irradiation externe des retinoblastomes

Energy Technology Data Exchange (ETDEWEB)

Benk, V; Habrand, J L; Bloch Michel, E; Soussaline, M; Sarrazin, D [Centre de Lutte Contre le Cancer Gustave-Roussy, 94 - Villejuif (France)

1993-01-01

From 1975 to 1985, 34 children with a non-metastatic retinoblastoma were irradiated at the Institut Gustave-Roussy. After enucleation, 19 bilateral tumors were irradiated by two lateral opposed fields and 15 unilateral tumors by one lateral and anterior field, in the case of optic nerve being histologically positive. Dose was 45 Gy, 1.8 Gy per fraction. The 10-year-survival rate for unilateral and bilateral retinoblastomas was 79%. Long term sequels were available for 25 patients: 88% retained one functional eye. Three children with bilateral retinoblastomas developed a cataract in the residual eye between 2 and 5 years after irradiation, none with unilateral tumor. Nine patients (36%), seven with unilateral and two with bilateral tumor developed a cosmetical problem that required multiple surgical rehabilitation between 3 and 14 years after irradiation. Nine children (36%), five with unilateral and four with bilateral tumors developed growth hormone deficit between 2 and 8 years after irradiation that required hormone replacement. Their pituitary gland received 22 to 40 Gy. No osteosarcoma occurred in this population. Among long-term sequels, following irradiation for retinoblastoma, cosmetical deformities represent disabling sequels that could justify new approaches in radiotherapy, as protontherapy combined with 3-D-treatment planning.

Craniospinal Irradiation for Trilateral Retinoblastoma Following Ocular Irradiation

Energy Technology Data Exchange (ETDEWEB)

Marks, Lawrence B.; Bentel, Gunilla; Sherouse, George W.; Spencer, David P.; Light, Kim

2015-01-15

A case study is presented. Craniospinal radiotherapy and a three-field pineal boost for trilateral retinoblastoma were delivered to a patient previously irradiated for ocular retinoblastoma. The availability of CT-based three-dimensional treatment planning provided the capability of identifying the previously irradiated volume as a three-dimensional anatomic structure and of designing a highly customized set of treatment beams that minimized reirradiation of that volume.

Facts about food irradiation: Safety of irradiation facilities

International Nuclear Information System (INIS)

1991-01-01

This fact sheet considers the safety of industrial irradiation facilities. Although there have been accidents, none of them has endangered public health or environmental safety, and the radiation processing industry is considered to have a very good safety record. Gamma irradiators do not produce radioactive waste, and the radiation sources at the facilities cannot explode nor in any other way release radioactivity into the environment. 3 refs

Food irradiation

International Nuclear Information System (INIS)

Mercader, J.P.; Emily Leong

1985-01-01

The paper discusses the need for effective and efficient technologies in improving the food handling system. It defines the basic premises for the development of food handling. The application of food irradiation technology is briefly discussed. The paper points out key considerations for the adoption of food irradiation technology in the ASEAN region (author)

Gamma-irradiation of tomatoes

International Nuclear Information System (INIS)

Tencheva, S.; Todorov, S.

1975-01-01

The influence of gamma-ray on tomatoes picked in a pink-red ripening stage, good for consumption, is studied. For that purpose tomatoes of ''Pioneer 2'' variety packed in perforated 500 g plastic bags were irradiated on a gamma device (Cobalt-60) at a dose power of 1900 rad/min with doses 200 or 300 krad. Samples were stored after irradiation at room temperature (20 - 22sup(o)C). Microbiological studies demonstrated that 44 resp. 99.96 per cent of the initial number of microorganisms was destroyed after irradiation with 200 resp. 300 krad. The time required for the number of microorganisms to be restored was accordingly increased. Irradiation delayed tomato ripening by 4 to 6 days, demonstrable by the reduced content of the basic staining substances - carotene and licopine. Immediately after irradiation the ascorbic acid content was reduced by an average of 13 per cent. After 18 days the amount of ascorbic acid in irradiated tomatoes was increased to a higher than the starting level, this is attributed to reductone formation during irradiation. The elevated total sugar content shown to be invert sugar was due to further tomato ripening. (Ch.K.)

food irradiation: activities and potentialities

International Nuclear Information System (INIS)

Doellstaedt, R.; Huebner, G.

1985-01-01

After the acceptance of food irradiation up to an overall average dose of 10 kGy recommended by the Joint FAO/IAEA/WHO Expert Committee on the Wholesomeness of Irradiated Food in October 1980, the G.D.R. started a programme for the development of techniques for food irradiation. A special onion irradiator was designed and built as a pilot plant for studying technological and economic parameters of the irradiation of onions. (author)

Blood irradiation: Rationale and technique

International Nuclear Information System (INIS)

Lewis, M.C.

1990-01-01

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

Irradiated produce reaches Midwest market

International Nuclear Information System (INIS)

Pszczola, D.E.

1992-01-01

In March 1992, the Chicago-area store gave its shoppers a choice between purchasing irradiated and nonirradiated fruits. The irradiated fruits were treated at Vindicator Inc., the first U.S. food irradiation facility (starting up on January 10, 1992). The plant, located in Mulberry, Fla., then shipped the fruits in trucks to the store where they were displayed under a hand-lettered sign describing the irradiated fruits and showing the irradiation logo

Ion irradiation to simulate neutron irradiation in model graphites: Consequences for nuclear graphite

Science.gov (United States)

Galy, N.; Toulhoat, N.; Moncoffre, N.; Pipon, Y.; Bérerd, N.; Ammar, M. R.; Simon, P.; Deldicque, D.; Sainsot, P.

2017-10-01

Due to its excellent moderator and reflector qualities, graphite was used in CO2-cooled nuclear reactors such as UNGG (Uranium Naturel-Graphite-Gaz). Neutron irradiation of graphite resulted in the production of 14C which is a key issue radionuclide for the management of the irradiated graphite waste. In order to elucidate the impact of neutron irradiation on 14C behavior, we carried out a systematic investigation of irradiation and its synergistic effects with temperature in Highly Oriented Pyrolitic Graphite (HOPG) model graphite used to simulate the coke grains of nuclear graphite. We used 13C implantation in order to simulate 14C displaced from its original structural site through recoil. The collision of the impinging neutrons with the graphite matrix carbon atoms induces mainly ballistic damage. However, a part of the recoil carbon atom energy is also transferred to the graphite lattice through electronic excitation. The effects of the different irradiation regimes in synergy with temperature were simulated using ion irradiation by varying Sn(nuclear)/Se(electronic) stopping power. Thus, the samples were irradiated with different ions of different energies. The structure modifications were followed by High Resolution Transmission Electron Microscopy (HRTEM) and Raman microspectrometry. The results show that temperature generally counteracts the disordering effects of irradiation but the achieved reordering level strongly depends on the initial structural state of the graphite matrix. Thus, extrapolating to reactor conditions, for an initially highly disordered structure, irradiation at reactor temperatures (200 - 500 °C) should induce almost no change of the initial structure. On the contrary, when the structure is initially less disordered, there should be a "zoning" of the reordering: In "cold" high flux irradiated zones where the ballistic damage is important, the structure should be poorly reordered; In "hot" low flux irradiated zones where the ballistic

Dosimetry for Crystals Irradiation

CERN Document Server

Lecomte, Pierre

2005-01-01

Before shipment to CMS, all PbWO4 crystals produced in China are irradiated there with 60 Co , in order to insure that the induced absorption coefficient is within specifications. Acceptance tests at CERNand at ENEA also include irradiation with gamma rays from 60 Co sources. There were initially discrepancies in quoted doses and doserates as well as in induced absorption coefficients. The present work resolves the discrepancies in irradiation measurements and defines common dosimetry methods for consistency checks between irradiation facilities.

Monte Carlo studies for irradiation process planning at the Portuguese gamma irradiation facility

International Nuclear Information System (INIS)

Oliveira, C.; Salgado, J.; Botelho, M.L.M. Luisa; Ferreira, L.M.

2000-01-01

The paper describes a Monte Carlo study for planning the irradiation of test samples for microbiological validation of distinct products in the Portuguese Gamma Irradiation Facility. Three different irradiation geometries have been used. Simulated and experimental results are compared and good agreement is observed. It is shown that Monte Carlo simulation improves process understanding, predicts absorbed dose distributions and calculates dose uniformity in different products. Based on these results, irradiation planning of the product can be performed

Influence of irradiation conditions on the gamma irradiation effect in polyethylene

International Nuclear Information System (INIS)

Kacarevic-Popovic, Z.; Gal, O.; Novakovic, L.J.; Secerov, B.

2002-01-01

Complete text of publication follows. The radiation cross-linking of polyethylene, due to its high cross-linking yield, has resulted in the radiation technology that has found application in radiation production of heat shrinkable structures and in improvement of mechanical and thermo-physical properties of oriented polyethylene objects. It is observed that the cross-linking efficiency decreases when the irradiation is carried out in the presence of oxygen. In order to estimate the conditions that improve cross-linking efficiency, gamma irradiation effect in two types of polyethylene, irradiated in water and air was investigated. The polyethylene samples used were the low density (LDPE) Lotrene CdF 0302 with 45% crystallinity and the high density (HDPE) Hiplex EHM 6003 with 73% crystallinity. Both kinds of samples, fixed in the Pyrex glass tubes, were simultaneously irradiated with 60 Co gamma rays in distilled water and air, at a doses rate of 9,5 kGy/h (determined by the Fricke dosimeter) at room temperature. Radiation induced oxidative degradation was followed through oxygen containing group formation by the carbonyl group band (1720 cm -1 ) and transvinylene group formation by the band at 966 cm -1 in the infrared spectra. Cross-linking efficiency was determined by gel content using the procedure of the extraction in xylene. The monitored effects of gamma irradiation in water and air point to the conclusion that irradiation in water leads to the lower oxidative degradation and higher cross-linking compared with the effects measured after irradiation in air

Neutron irradiation facility and its characteristics

International Nuclear Information System (INIS)

Oyama, Yukio; Noda, Kenji

1995-01-01

A neutron irradiation facility utilizing spallation reactions with high energy protons is conceived as one of the facilities in 'Proton Engineering center (PEC)' proposed at JAERI. Characteristics of neutron irradiation field of the facility for material irradiation studies are described in terms of material damage parameters, influence of the pulse irradiation, irradiation environments other than neutronics features, etc., comparing with the other sorts of neutron irradiation facilities. Some perspectives for materials irradiation studies using PEC are presented. (author)

Structure and properties of UV-irradiated LLDPE and alloy of PA66 and the irradiated LLDPE

International Nuclear Information System (INIS)

Ran Qianping; Zou Hua; Wu Shishan; Shen Jian

2006-01-01

Some oxygen-containing groups such as C=O, C-O and -OH were introduced onto linear low-density polyethylene (LLDPE) chains by UV irradiation in air. Their concentration increased with the irradiation time. Crystal shape of the irradiated LLDPE remained an orthorhombic structure, while space of the crystalline plane kept unchanged. The melting temperature and crystallinity decreased due to the LLDPE chain scission into small molecules compound and crystalline defects caused by UV irradiation. Compared with pristine LLDPE, hydrophilicity of the irradiated LLDPE increased due to the introduction of polar oxygen-containing groups, but the tensile strength decreased due to the LLDPE chain degradation and reduction of crystallinity. The temperature of initial weight loss of the irradiated LLDPE was lower than that of pristine LLDPE. An alloy of PA66 and the irradiated LLDPE (irradiated PA66/LLDPE) was prepared by melting blend at 260-270 degree C. Compared to non-irradiated PA66/LLDPE alloy, dispersion of LLDPE particles in the irradiated PA66/LLDPE alloy and interfacial interactions between the components were markedly improved. Therefore, tensile strength and impact strength of the irradiated PA66/ LLDPE were higher than those of the control. (authors)

Nuclear irradiation parameters of beryllium under fusion, fission and IFMIF irradiation conditions

International Nuclear Information System (INIS)

Fischer, U.; Chen, Y.; Leichtle, D.; Simakov, S.; Moeslang, A.; Vladimirov, P.

2004-01-01

A computational analysis is presented of the nuclear irradiation parameters for Beryllium under irradiation in typical neutron environments of fission and fusion reactors, and of the presently designed intense fusion neutron source IFMIF. The analysis shows that dpa and Tritium production rates at fusion relevant levels can be achieved with existing high flux fission reactors while the achievable Helium production is too low. The resulting He-Tritium and He/dpa ratios do not meet typical fusion irradiation conditions. Irradiation simulations in the medium flux test modules of the IFMIF neutron source facility were shown to be more suitable to match fusion typical irradiation conditions. To achieve sufficiently high production rates it is suggested to remove the creep-fatigue testing machine together with the W spectra shifter plate and move the tritium release module upstream towards the high flux test module. (author)

Dose Distribution of Gamma Irradiators

International Nuclear Information System (INIS)

Park, Seung Woo; Shin, Sang Hun; Son, Ki Hong; Lee, Chang Yeol; Kim, Kum Bae; Jung, Hai Jo; Ji, Young Hoon

2010-01-01

Gamma irradiator using Cs-137 have been widely utilized to the irradiation of cell, blood, and animal, and the dose measurement and education. The Gamma cell 3000 Elan (Nordion International, Kanata, Ontario, Canada) irradiator was installed in 2003 with Cs-137 and dose rate of 3.2 Gy/min. And the BioBeam 8000 (Gamma-Service Medical GmbH, Leipzig, Germany) irradiator was installed in 2008 with Cs-137 and dose rate of 3.5 Gy/min. Our purpose was to evaluate the practical dosimetric problems associated with inhomogeneous dose distribution within the irradiated volume in open air state using glass dosimeter and Gafchromic EBT film dosimeter for routine Gamma irradiator dosimetry applications at the KIRAMS and the measurements were compared with each other. In addition, an user guideline for useful utilization of the device based on practical dosimetry will be prepared. The measurement results of uniformity of delivered dose within the device showed variation more than 14% between middle point and the lowest position at central axis. Therefore, to maintain dose variation within 10%, the criteria of useful dose distribution, for research radiation effects, the irradiated specimen located at central axis of the container should be placed within 30 mm from top and bottom surface, respectively. In addition, for measurements using the film, the variations of dose distribution were more then 50% for the case of less than 10 second irradiation, mostly within 20% for the case of more than 20 second irradiation, respectively. Therefore, the irradiation experiments using the BioBeam 8000 irradiator are recommended to be used for specimen required at least more than 20 second irradiation time.

Detection methods for irradiated foods

International Nuclear Information System (INIS)

Dyakova, A.; Tsvetkova, E.; Nikolova, R.

2005-01-01

In connection with the ongoing world application of irradiation as a technology in Food industry for increasing food safety, it became a need for methods of identification of irradiation. It was required to control international trade of irradiated foods, because of the certain that legally imposed food laws are not violated; supervise correct labeling; avoid multiple irradiation. Physical, chemical and biological methods for detection of irradiated foods as well principle that are based, are introducing in this summary

Studies of blood irradiator application

International Nuclear Information System (INIS)

Li Wenhong; Lu Yangqiao

2004-01-01

Transfusion is an important means for medical treatment, but it has many syndromes such as transfusion-associated graft-versus-host disease, it's occurrence rate of 5% and above 90% death-rate. Now many experts think the only proven method is using blood irradiator to prevent this disease. It can make lymphocyte of blood product inactive, so that it can not attack human body. Therefore, using irradiation blood is a trend, and blood irradiator may play an important role in medical field. This article summarized study of blood irradiator application, including the meaning of blood irradiation, selection of the dose for blood irradiation and so on

Irradiation of packaged food

International Nuclear Information System (INIS)

Kilcast, D.

1990-01-01

Food irradiation is used to improve the safety of food by killing insects and microorganisms, to inhibit sprouting in crops such as onions and potatoes and to control ripening in agricultural produce. In order to prevent re-infestation and re-contamination it is essential that the food is suitably packed. Consequently, the packaging material is irradiated whilst in contact with the food, and it is important that the material is resistant to radiation-induced changes. In this paper the nature of the irradiation process is reviewed briefly, together with the known effects of irradiation on packaging materials and their implications for the effective application of food irradiation. Recent research carried out at the Leatherhead Food RA on the possibility of taint transfer into food is described. (author)

Issues in food irradiation

International Nuclear Information System (INIS)

Mills, S.

1987-04-01

This discussion paper has two goals: first, to raise public awareness of food irradiation, an emerging technology in which Canada has the potential to build a new industry, mainly oriented to promising overseas markets; and second, to help build consensus among government and private sector decision makers about what has to be done to realize the domestic and export potential. The following pages discuss the potential of food irradiation; indicate how food is irradiated; outline the uses of food irradiation; examine questions of the safety of the equipment and both the safety and nutritional value of irradiated food; look at international commercial developments; assess the current and emerging domestic scene; and finally, draw some conclusions and offer suggestions for action

The effect of γ-irradiation on changes of blood chemistry in RC-MAP after irradiation

International Nuclear Information System (INIS)

Hirose, Tetsuhito; Katayama, Norifumi; Okamoto, Yukiharu; Tsuda, Tadaaki; Ota, Kiichiro; Nishioka, Shingo; Tsumura, Michiyo; Yukawa, Mariko

1997-01-01

Irradiation to transfused blood is obligated to prevent from post transfusion graft-versus-host disease (PT-GVHD) by inactivation of lymphocytes. The rule of irradiated dose was not determined, it's dose being ranged from 15 to 50 Gy, but it's dose was done by each institute. We investigated an adequate dose of irradiation to blood on effects of plasma Na, potassium (K), Chloride (Cl), LDH, GOT, BUN and total protein (T.P) after irradiation of transfused blood. By comparison of plasma Na and K in non-irradiated blood, plasma K was increased and decreased in a parallelism of period of stored irradiated blood, two days after it's irradiation. Effects of Na and K levels were dose dependent. LDH level was increased in a time-dependency, but not by it's dose plasma Cl, LDH, GOT, BUN and T.P levels were not influenced. Our results indicated that the mechanism of RBC permeability after irradiation seemed to be inactivated Na-K ATPase activity in RBC cell membrane. (author)

Gemstone dedicated gamma irradiation development

Energy Technology Data Exchange (ETDEWEB)

Omi, Nelson M.; Rela, Paulo R. [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)]. E-mails: nminoru@ipen.br; prela@ipen.br

2007-07-01

The gemstones gamma irradiation process to enhance the color is widely accepted for the jewelry industry. These gems are processed in conventional industrial gamma irradiation plant which are optimized for other purposes, using underwater irradiation devices with high rejection rate due to its poor dose uniformity. A new conception design, which states the working principles and manufacturing ways of the device, was developed in this work. The suggested device's design is based on the rotation of cylindrical baskets and their translation in circular paths inside and outside a cylindrical source rack as a planetary system. The device is meant to perform the irradiation in the bottom of the source storage pool, where the sources remain always shielded by the water layer. The irradiator matches the Category III IAEA classification. To verify the physical viability of the basic principle, tests with rotating cylindrical baskets were performed in the Multipurpose Irradiator constructed in the CTR, IPEN. Also, simulations using the CADGAMMA software, adapted to simulate underwater irradiations, were performed. With the definitive optimized irradiator, the irradiation quality will be enhanced with better dose control and the production costs will be significantly lower than market prices due to the intended treatment device's optimization. This work presents some optimization parameters and the expected performance of the irradiator. (author)

Vitamin A in irradiated foodstuffs

International Nuclear Information System (INIS)

Diehl, J.F.

1979-01-01

Vitamin A losses induced by 10 MeV electrons in cream cheese, calf liver sausage, pig liver, whole egg powder and margarine continued to increase during storage for 4-8 weeks in presence of air. Thus, vitamin A loss in sausage irradiated with 5 Mrad was 22% on the day after irradiation, 61% after 4 weeks. Irradiation and storage at 0 0 C instead of at ambient temperature reduced these losses considerably. Exclusion of air (vacuum, nitrogen) or irradiation on dry ice (approx. -80 0 C) were even more effective in preventing destruction of vitamin A. After 4 weeks of storage, cream cheese irradiated at 5 Mrad had lost 60% when irradiated and stored in air at ambient temperature, 20% in nitrogen atmosphere, 5% in vacuum package, and 5% when irradiated on dry ice and stored at ambient temperture. (orig.) [de

Vitamin A in irradiated foodstuffs

International Nuclear Information System (INIS)

Diehl, J.F.

1979-01-01

Vitamin A losses induced by 10 MeV electrons in cream cheese, calf liver sausage, pig liver, whole egg powder and magarine continued to increase during storage for 4-8 weeks in presence of air. Thus, vitamin A loss in sausage irradiated with 5 Mrad was 22% on the day after irradiation, 61% after 4 weeks. Irradiation and storage at 0 0 C instead of ambient temperature reduced these losses considerably. Exclusion of air (vacuum, nitrogen) or irradiation on dry ice (approx. -80 0 C) were even more effective in preventing destruction of vitamin A. After 4 weeks of storage, cream cheese irradiated at 5 Mrad had lost 60% when irradiated and stored in air at ambient temperature, 20% in nitrogen atmosphere, 5% in vacuum package, and 5% when irradiated on dry ice and stored at ambient temperature. (orig.) [de

Vitamin A in irradiated foodstuffs

Energy Technology Data Exchange (ETDEWEB)

Diehl, J F [Bundesforschungsanstalt fuer Ernaehrung, Karlsruhe (Germany, F.R.)

1979-01-01

Vitamin A losses induced by 10 MeV electrons in cream cheese, calf liver sausage, pig liver, whole egg powder and margarine continued to increase during storage for 4-8 weeks in presence of air. Thus, vitamin A loss in sausage irradiated with 5 Mrad was 22% on the day after irradiation, 61% after 4 weeks. Irradiation and storage at 0/sup 0/C instead of at ambient temperature reduced these losses considerably. Exclusion of air (vacuum, nitrogen) or irradiation on dry ice (approx. -80/sup 0/C) were even more effective in preventing destruction of vitamin A. After 4 weeks of storage, cream cheese irradiated at 5 Mrad had lost 60% when irradiated and stored in air at ambient temperature, 20% in nitrogen atmosphere, 5% in vacuum package, and 5% when irradiated on dry ice and stored at ambient temperature.

Vitamin A in irradiated foodstuffs

Energy Technology Data Exchange (ETDEWEB)

Diehl, J F [Bundesforschungsanstalt fuer Ernaehrung, Karlsruhe (Germany, F.R.)

1979-01-01

Vitamin A losses induced by 10 MeV electrons in cream cheese, calf liver sausage, pig liver, whole egg powder and magarine continued to increase during storage for 4-8 weeks in presence of air. Thus, vitamin A loss in sausage irradiated with 5 Mrad was 22% on the day after irradiation, 61% after 4 weeks. Irradiation and storage at 0/sup 0/C instead of ambient temperature reduced these losses considerably. Exclusion of air (vacuum, nitrogen) or irradiation on dry ice (approx. -80/sup 0/C) were even more effective in preventing destruction of vitamin A. After 4 weeks of storage, cream cheese irradiated at 5 Mrad had lost 60% when irradiated and stored in air at ambient temperature, 20% in nitrogen atmosphere, 5% in vacuum package, and 5% when irradiated on dry ice and stored at ambient temperature.

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

Science.gov (United States)

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

2002-03-01

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

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

International Nuclear Information System (INIS)

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

2002-01-01

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

A study on UV irradiated HDPE

International Nuclear Information System (INIS)

Sang Haibo; Liu Zimin; Wu Shishan; Shen Jian

2006-01-01

The structure and properties of HDPE irradiated by ultraviolet (UV) in ozone atmosphere were studied by FT-IR, XPS, gel, and water contact angle test. The oxygen-containing groups such as C=O, C-O and C(=O)O were introduced onto high density polyethylene (HDPE) chains through ultraviolet irradiation in ozone atmosphere, their content increased with the UV irradiation time. Under the same UV irradiation conditions, amount of the oxygen-containing groups introduced in ozone atmosphere was more than that in air atmosphere, indicating that the speed of oxygen-containing groups introduced through UV irradiation in ozone atmosphere was faster than that in air. Therefore, HDPE could be quickly functionalized through UV irradiation in ozone atmosphere. There was no gel formed in the HDPE irradiated in ozone atmosphere. After UV irradiation, the water contact angle of HDPE decreased, and its hydrophilicity was improved, suggesting that the compatibility between the irradiated HDPE and polar polymer or inorganic fillers may be better. Compared with HDPE, the temperature of initial weight loss for irradiated HDPE decreased. The structure and properties of irradiated HDPE/CaCO 3 blend were also investigated. The results showed that the compatibility and interfacial action of the irradiated HDPE/CaCO 3 blend were improved compared to that of HDPE/CaCO 3 blend. The mechanical properties of irradiated HDPE/CaCO 3 blend increased with increasing irradiation time. (authors)

Detection methods of irradiated foodstuffs

Energy Technology Data Exchange (ETDEWEB)

Ponta, C C; Cutrubinis, M; Georgescu, R [IRASM Center, Horia Hulubei National Institute for Physics and Nuclear Engineering, PO Box MG-6, RO-077125 Magurele-Bucharest (Romania); Mihai, R [Life and Environmental Physics Department, Horia Hulubei National Institute for Physics and Nuclear Engineering, PO Box MG-6, RO-077125 Magurele-Bucharest (Romania); Secu, M [National Institute of Materials Physics, Bucharest (Romania)

2005-07-01

Full text: Food irradiation has, in certain circumstances, an important role to play both in promoting food safety and in reducing food losses. The safety and availability of nutritious food are essential components of primary health care. WHO actively encourages the proper use of food irradiation in the fight against foodborne diseases and food losses. To this end, it collaborates closely with FAO and IAEA. Food irradiation can have a number of beneficial effects, including delay of ripening and prevention of sprouting; control of insects, parasites, helminths, pathogenic and spoilage bacteria, moulds and yeasts; and sterilization, which enables commodities to be stored unrefrigerated for long periods. The 1990s witnessed a significant advancement in food irradiation processing. As a result, progress has been made in commercialization of the technology, culminating in greater international trade in irradiated foods and the implementation of differing regulations relating to its use in many countries. Codex General Standard for Irradiated Foodstuffs and Recommended International Code of Practice for the Operation of Irradiation Facilities Used for the Treatment of Foods regulate food irradiation at international level. At European Union level there are in power Directive 1999/2/EC and Directive1999/3/EC. Every particular country has also its own regulations regarding food irradiation. In Romania, since 2002 the Norms Regarding Foodstuffs and Food Ingredients Treated by Ionizing Radiation are in power. These Norms are in fact the Romanian equivalent law of the European Directives 1999/2/EC and 1999/3/EC. The greater international trade in irradiated foods has led to the demand by consumers that irradiated food should be clearly labeled as such and that methods capable of differentiating between irradiated and nonirradiated products should be available. Thus a practical basis was sought to allow consumers to exercise a free choice as to which food they purchase. If a

Containers in food irradiation

International Nuclear Information System (INIS)

Bolumen, S.; Espinosa, R.

1997-01-01

The preservation of food by irradiation is promising technology which increases industrial application. Packaging of irradiated foods is an integral part of the process. Judicious selection of the package material for successful trade is essential. In this paper is presented a brief review of important aspects of packaging in food irradiation [es

Nutritional aspects of irradiated shrimp

International Nuclear Information System (INIS)

Shamsuzzaman, K.

1989-11-01

Data available in the literature on the nutritional aspects of irradiated shrimp are reviewed and the indication is that irradiation of shrimp at doses up to about 3.2 kGy does not significantly affect the levels of its protein, fat, carbohydrate and ash. There are no reports on the effect of irradiation of shrimp above 3.2 kGy on these components. Limited information available indicates that there are some minor changes in the fatty acid composition of shrimp as a result of irradiation. Irradiation also causes some changes in the amino acid composition of shrimp; similar changes occur due to canning and hot-air drying. Some of the vitamins in shrimp, such as thiamine, are lost as a result of irradiation but the loss is less extensive than in thermally processed shrimp. Protein quality of shrimp, based on the growth of rats as well as that of Tetrahymena pyriformis, is not affected by irradiation. No adverse effects attributed to irradiation were found either in short-term or long-term animal feeding tests

The present situation of irradiation services

International Nuclear Information System (INIS)

Hironiwa, Takayuki

2014-01-01

The present state of food irradiation in Japan is presented from a point of view of a trustee for irradiation business. Radiation sprout inhibition of potatoes, only approved by Government, and spice treatment, now being applied for, are explained. Existing establishments capable of entrusting irradiation services as business in Japan are outlined including Co-60 gamma ray and X-ray irradiation and electron beam irradiation. Principles of irradiation-induced physical and chemical effects in irradiated materials specifically organic polymers and brief explanation of facilities together with safety devices are also explained. (S. Ohno)

Commercial food irradiation in practice

International Nuclear Information System (INIS)

Leemhorst, J.G.

1990-01-01

Dutch research showed great interest in the potential of food irradiation at an early stage. The positive research results and the potential applications for industry encouraged the Ministry of Agriculture and Fisheries to construct a Pilot Plant for Food Irradiation. In 1967 the Pilot Plant for Food Irradiation in Wageningen came into operation. The objectives of the plant were: research into applications of irradiation technology in the food industry and agricultural industry; testing irradiated products and test marketing; information transfer to the public. (author)

Food irradiation: progress in Canada

International Nuclear Information System (INIS)

Wilson, B.K.

1985-01-01

The subject is discussed under the headings: food irradiation regulatory situation in Canada; non-regulatory developments (poultry irradiation; fish irradiation; Government willingness to fund industry initiated projects; Government willingness to establish food irradiation research and pilot plant facilities; food industry interest is increasing significantly; Canadian Consumers Association positive response; the emergence of new consulting and entrepreneurial firms). (U.K.)

Food irradiation and the consumer

International Nuclear Information System (INIS)

Thomas, P.A.

1990-01-01

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

Dosimetry of blood irradiator - 2000

International Nuclear Information System (INIS)

Mhatre, Sachin G.V.; Shinde, S.H.; Bhat, R.M.; Rao, Suresh; Sharma, D.N.

2008-01-01

Full text: Blood transfusion to an immunodeficient or immunosuppressed patient has a high risk involved due to occurrence of Transfusion Graft Versus Host Disease (T-GVHD). In order to eliminate this problem, blood is routinely exposed to ionizing radiation (gamma) prior to transfusion. Doses ranging from 15 Gy to 50 Gy can prevent T-GVHD. Aim of the present work was to perform dosimetry of 60 Co Blood Irradiator-2000 developed by Board of Radiation and isotope Technology (BRIT), India; using FBX dosimetric system. Dose-rate measured by FBX dosimeter was intercompared with Fricke dosimeter, which is a Reference Standard dosimeter. Experiments included measurement of dose-rate at the centre of irradiation volume, dose mapping in the central vertical plane within the irradiation volume and measurement of average dose received by blood sample using blood bags filled with FBX dosimeter by simulating actual irradiation conditions. During irradiation, the sample chamber is retracted into a cylindrical source cage, so that the sample is irradiated from all sides uniformly. Blood irradiator-2000 has sample rotation facility for increasing the dose uniformity during irradiation. The performance of this was investigated by measuring the central vertical plane dose profile in stationary state as well in rotation using the sample rotation facility (60 rpm). FBX being an aqueous dosimetric system fills container of irregular shape being irradiated hence can be used to integrate the dose over the volume. Dose-rate measured by FBX dosimeter was intercompared with Fricke dosimeter, which was in good agreement. Average dose-rate at the centre of irradiation volume and within the blood bag was measured by FBX and Fricke dosimeters. It was observed that dose profiles measured by FBX and Fricke dosimeters agreed within ± 2%. Dose uniformity within the irradiation volume was found to reduce from 21% to 17% when the sample rotation facility was used. Thus, it is suggested by the

The response of previously irradiated mouse skin to heat alone or combined with irradiation: influence of thermotolerance

International Nuclear Information System (INIS)

Wondergem, J.; Haveman, J.

1983-01-01

The effect of previous x-irradiation on the response to hyperthermia (44 0 C), x-irradiation, and irradiation combined with hyperthermia (43 0 C or 44 0 C) was studied in mouse foot skin. Irradiation of mice feet 90 days before, with 20 Gy, increased the subsequent response to heat alone, or combined with irradiation, as well as to irradiation alone. It had little effect on the thermal enhancement ratios for both acute and late skin reactions. Memory of the previous irradiation treatment could be masked when the temperature of the subsequent heat treatment alone, or combined with irradiation, was 44 0 C. Priming heat treatment induced resistance to a subsequent heat treatment and to a subsequent combined irradiation-heat treatment in normal as well as previously irradiated skin. When late skin reaction was considered, a larger 'memory' of the previous irradiation treatment was always evident, compared to acute skin reaction: the 'remembered' dose in the late skin reaction was about twice the 'remembered' dose in the acute reaction. (U.K.)

IAEA and food irradiation

International Nuclear Information System (INIS)

Machi, Sueo

1995-01-01

IAEA was founded in 1957. 122 countries take part in it. It is operated with the yearly ordinary budget of about 20 billion yen and the technical cooperation budget of about 6 billion yen and by 2200 personnel. Its two important roles are the promotion of the peaceful utilization of atomic energy and the prevention of nuclear proliferation. The activities of IAEA are shown. The cooperation with developing countries and the international research cooperation program are the important activities. The securing of foods is an urgent subject, and the utilization of radiation and isotopes has been promoted, aiming at sustaining agriculture. The necessity of food irradiation is explained, and at present, commercial food irradiation is carried out in 28 countries including Japan. The irradiation less than 10 kGy does not cause poisonous effect in any food, according to JECFI. The new international agreement is expected to be useful for promoting the international trade of irradiated foods. The international cooperation for the spread of food irradiation and the public acceptance of food irradiation are reported. (K.I.)

Food irradiation in Japan

International Nuclear Information System (INIS)

Ito, Hitoshi

1995-01-01

The basic research on food irradiation in Japan was begun around 1955 by universities and national laboratories. In 1967, food irradiation was designated to the specific general research on atomic energy, and the national project on large scale was continued until 1983. As the result, the treatment of germination prevention for potatoes was approved by the Ministry of Health and Welfare in 1972. The Co-60 gamma ray irradiation facility of Shihoro Agricultural Cooperative is famous as the facility that succeeded in the practical use of food irradiation for the first time in the world. But the practical use of food irradiation stagnates and the research activities were reduced in Japan due to the circumstances thereafter. The effect of radiation to foods and living things is explained. The features of the radiation treatment of foods are small temperature rise, large transmissivity, no residue, the small loss of nutrition and large quantity, continuous treatment. The safety of irradiated foods is explained. The subjects for hereafter are discussed. (K.I.)

The wholesomeness of irradiated food

International Nuclear Information System (INIS)

Elias, P.S.; Matsuyama, A.

1978-01-01

It is apparent that there is a need for protection of the consumer and a need for governmental authorities to insure a safe and wholesome food supply for the population. Based on objective and scientific evidence regarding the safety of food irradiation, national and international health authorities are able to determine whether irradiated food is acceptable for human consumption. Following a thorough review of all available data, the Joint FAO/IAEA/WHO Expert Committee unconditionally approved wheat and ground wheat products and papaya irradiated for disingestation at a maximum dose of 100 krad, potatoes irradiated for sprout control at a maximum dose not exceeding 15 krad, and chicken irradiated at a maximum dose of 700 krad to reduce microbiological spoilage. Lastly, it unconditionally approved strawberries irradiated at a maximum dose of 300 krad to prolong storage. Onions at irradiated for sprout control at a maximum dose of 15 krad were temporarily approved, subject to preparation of further data on multigeneration reproduction studies on rats. Codfish and redfish eviscerated after irradiation at a maximum dose of 220 krad to reduce microbiological spoilage were also approved, based on the results of various studies in progress. Temporary, conditional approval of rice irradiated for insect disinfestation at a maximum dose of 100 krad was based on results of long-term studies on rats and monkies, available in the next review. Due to insufficient data, no decision regarding irradiated mushrooms was made. (Bell, E.)

Materials irradiation research in neutron science

Energy Technology Data Exchange (ETDEWEB)

Noda, Kenji; Oyama, Yukio [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

1997-11-01

Materials irradiation researches are planned in Neutron Science Research Program. A materials irradiation facility has been conceived as one of facilities in the concept of Neutron Science Research Center at JAERI. The neutron irradiation field of the facility is characterized by high flux of spallation neutrons with very wide energy range up to several hundred MeV, good accessibility to the irradiation field, good controllability of irradiation conditions, etc. Extensive use of such a materials irradiation facility is expected for fundamental materials irradiation researches and R and D of nuclear energy systems such as accelerator-driven incineration plant for long-lifetime nuclear waste. In this paper, outline concept of the materials irradiation facility, characteristics of the irradiation field, preliminary technical evaluation of target to generate spallation neutrons, and materials researches expected for Neutron Science Research program are described. (author)

Kraft cooking of gamma irradiated wood, (1). Effect of alcohol additives on pre-irradiation

Energy Technology Data Exchange (ETDEWEB)

Inaba, M; Meshitsuka, G; Nakano, J [Tokyo Univ. (Japan). Faculty of Agriculture

1979-12-01

Studies have been made of kraft cooking of gamma irradiated wood. Beech (Fagus crenata Blume) wood meal suspended in aqueous alkaline alcohol was irradiated up to 1.5 KGy (0.15 Mrad) with gamma rays from a Co-60 source in the presence or absence of oxygen. The irradiated wood meals were washed thoroughly with fresh water, air dried and cooked under the ordinary cooking conditions. The results are summarized as follows: (1) Pre-irradiation in aqueous alkali have negligible effect on kraft cooking. (2) In the case of ethanol addition (50 g/l), pre-irradiation in vacuo shows acceleration of delignification and stabilization of carbohydrates during kraft cooking. Cooked yield gain by pre-irradiation was about 1.2 in all, over the range of delignification from 80 to 90%. Aqueous ethanol without alkali also shows positive but smaller effect than that with alkali. (3) Propanol, iso-propanol and butanol show positive but smaller effects than ethanol. However, methanol does not show any positive effect. (4) Irradiation in the presence of oxygen does not show any attractive effect on kraft cooking.

Consumer acceptance of irradiated poultry

International Nuclear Information System (INIS)

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

1995-01-01

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

Consumer acceptance of irradiated poultry.

Science.gov (United States)

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

1995-08-01

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

Total lymphoid irradiation

International Nuclear Information System (INIS)

Sutherland, D.E.; Ferguson, R.M.; Simmons, R.L.; Kim, T.H.; Slavin, S.; Najarian, J.S.

1983-01-01

Total lymphoid irradiation by itself can produce sufficient immunosuppression to prolong the survival of a variety of organ allografts in experimental animals. The degree of prolongation is dose-dependent and is limited by the toxicity that occurs with higher doses. Total lymphoid irradiation is more effective before transplantation than after, but when used after transplantation can be combined with pharmacologic immunosuppression to achieve a positive effect. In some animal models, total lymphoid irradiation induces an environment in which fully allogeneic bone marrow will engraft and induce permanent chimerism in the recipients who are then tolerant to organ allografts from the donor strain. If total lymphoid irradiation is ever to have clinical applicability on a large scale, it would seem that it would have to be under circumstances in which tolerance can be induced. However, in some animal models graft-versus-host disease occurs following bone marrow transplantation, and methods to obviate its occurrence probably will be needed if this approach is to be applied clinically. In recent years, patient and graft survival rates in renal allograft recipients treated with conventional immunosuppression have improved considerably, and thus the impetus to utilize total lymphoid irradiation for its immunosuppressive effect alone is less compelling. The future of total lymphoid irradiation probably lies in devising protocols in which maintenance immunosuppression can be eliminated, or nearly eliminated, altogether. Such protocols are effective in rodents. Whether they can be applied to clinical transplantation remains to be seen

Post-irradiation diarrhea

International Nuclear Information System (INIS)

Meerwaldt, J.H.

1984-01-01

In radiotherapy of pelvic cancers, the X-ray dose to be delivered to the tumour is limited by the tolerance of healthy surrounding tissue. In recent years, a number of serious complications of irradiation of pelvic organs were encountered. Modern radiotherapy necessitates the acceptance of a calculated risk of complications in order to achieve a better cure rate. To calculate these risks, one has to know the radiation dose-effect relationship of normal tissues. Of the normal tissues most at risk when treating pelvic tumours only the bowel is studied. In the literature regarding post-irradiation bowel complications, severe and mild complications are often mixed. In the present investigation the author concentrated on the group of patients with relatively mild symptoms. He studied the incidence and course of post-irradiation diarrhea in 196 patients treated for carcinoma of the uterine cervix or endometrium. The aims of the present study were: 1) to determine the incidence, course and prognostic significance of post-irradiation diarrhea; 2) to assess the influence of radiotherapy factors; 3) to study the relation of bile acid metabolism to post-irradiation diarrhea; 4) to investigate whether local factors (reservoir function) were primarily responsible. (Auth.)

Microstructure and mechanical properties of neutron irradiated OFHC-copper before and after post-irradiation annealing

International Nuclear Information System (INIS)

Singh, B.N.; Edwards, D.J.; Toft, P.

2001-02-01

Tensile specimens of OFHC-copper were irradiated with fission neutrons in the DR-3 reactor at Risoe National Laboratory at 100 deg. C to different displacement dose levels in the range of 0.01 to 0.3 dpa (NRT). Some of the specimens were tensile tested in the as-irradiated condition at 100 deg. C whereas other were given a post-irradiation annealing at 300 deg. C for 50 h and subsequently tested at 100 deg. C. Transmission electron microscopy was used to characterize the microstructure of specimens in the as-irradiation as well as irradiation and annealed conditions both before and after tensile deformation. The results show that while the interstitial loop microstructure coarsens with irradiation dose, no significant changes are observed in the population of stacking fault tetrahedra. The results also illustrates that the post-irradiation annealing leads to only a partial recovery and that the level of recovery depends on the irradiation dose level. However, the post-irradiation annealing eliminates the problem of yield drop and reinstates enough uniform elongation to render the material useful again. These results are discussed in terms of the cascade induced source hardening (CISH) and the dispersed barrier hardening (DBH) models. Both technological and scientific implications of these results are considered. (au)

New multipurpose gamma-irradiation facility

Energy Technology Data Exchange (ETDEWEB)

Huebner, G

1985-01-01

In the past 3 years much work has been done in the G.D.R. on food irradiation. The experiments have shown that this treatment gives favourable results in many products such as spices, onions, potatoes, chicken, animal feeds, fodder yeast, drugs and vaccines. Economic aspects of food irradiation require the effective use of an irradiation plant and cobalt-60. Therefore, a new multipurpose irradiation facility was developed, applicable as an onion irradiator with a capacity of about 15 ton/h and for the simultaneous irradiation of different products (spices, animal feed, chicken, etc.) in closed product boxes with a size of 1.2 m x 1.0 m x 1.2 m. A microcomputer controls the transport of product boxes around the gamma sources.

Status of irradiation capsule design

International Nuclear Information System (INIS)

Nagata, Hiroshi; Yamaura, Takayuki; Nagao, Yoshiharu

2013-01-01

For the irradiation test after the restart of JMTR, further precise temperature control and temperature prediction are required. In the design of irradiation capsule, particularly sophisticated irradiation temperature prediction and evaluation are urged. Under such circumstance, among the conventional design techniques of irradiation capsule, the authors reviewed the evaluation method of irradiation temperature. In addition, for the improvement of use convenience, this study examined and improved FINAS/STAR code in order to adopt the new calculation code that enables a variety of analyses. In addition, the study on the common use of the components for radiation capsule enabled the shortening of design period. After the restart, the authors will apply this improved calculation code to the design of irradiation capsule. (A.O.)

Fish irradiation

International Nuclear Information System (INIS)

Kovacs, J.; Tengumnuay, C.; Juangbhanich, C.

1970-01-01

Chub-mackerel was chosen for the study because they are the most common fish in Thailand. Preliminary investigations were conducted to determine the maximum radiation dose of gamma-rays by organoleptic tests. The samples were subjected to radiation at various doses up to 4 Mrad. Many experiments were conducted using other kinds of fish. The results showed that 1 Mrad would be the maximum acceptable dose for fish. Later, the influence of the radiation dose from 0.1-1 Mrad was studied in order to find the optimum acceptable dose for preservation of fish without off-flavour. For this purpose, the Hedonic scale was used. It was found that 0.2 and 0.5 Mrad gave the best result on Chub mackerel. The determinations of optimum dose, organoleptic, microbiological and trimethylamine content changes were done. The results showed that Chub mackerel irradiated at 0.2, 0.5 and 1 Mrad stored at 3 0 C for 71 days were still acceptable, on the contrary the untreated samples were found unacceptable at 14 days. The trimethylamine increment was significantly higher in the untreated samples. At 15 days storage, trimethylamine in the non-irradiated Chub-mackerel was about 10 times higher than the irradiated ones. At 51 and 79 days storage, about 13 times higher in the control samples than the irradiated samples except 0.1 Mrad. Only 2 times higher was found for the 0.1 Mrad. The microbiological results showed that the irradiation above 0.2 Mrad gave favorable extension of shelf-life of fish

Immunocytoadherence and sublethal irradiation

International Nuclear Information System (INIS)

Beaumariage, M.L.; Hiesche, K.; Revesz, L.; Haot, J.

1975-01-01

In sublethally irradiated CBA mice, the relative and absolute numbers of spontaneous rosette forming cells against sheep erythrocytes are markedly decreased in bone marrow. The decrease of the absolute number of spontaneous RFC is also important in the spleen in spite of an increase of the RFC relative number above the normal values between the 8th and 12th day after irradiation. The graft of normal bone marrow cells immediately after irradiation or the shielding of a medullary area during irradiation promotes the recovery of the immunocytoadherence capacity of the bone marrow cells but not of the spleen cells [fr

e-Learning Course on Food Irradiation

International Nuclear Information System (INIS)

Hénon, Yves

2016-01-01

Since May 2015, an online, interactive, multi-media and self-study course on Food Irradiation - Technology, Applications and Good Practices has been made available by the Food and Environmental Protection Section. This e-learning Course on Food Irradiation was initiated during a project (RAS/05/057) of the Regional Cooperative Agreement (RCA) Implementing Best Practices of Food Irradiation for Sanitary and Phytosanitary Purposes. Each module contains: • A lesson, largely based on the Manual of Good Practice in Food except for the first part (Food Irradiation) for which expanding the contents and addressing frequently asked questions seemed necessary. The latest chapters will help operators of irradiation facilities to appreciate and improve their practices. • A section called ‘Essentials’ that summarizes the key points. • A quiz to assess the knowledge acquired by the user from the course material. The quiz questions take a variety of forms: answer matching, multiple choice, true or false, picture selection, or simple calculation. Videos, Power Point presentations, pdf files and pictures enrich the contents. The course includes a glossary and approximately 80 downloadable references. These references cover safety of irradiated food, effects of irradiation on the nutritional quality of food, effects of irradiation on food microorganisms, insects and parasites, effects of irradiation on parasites, sanitary and phytosanitary applications of irradiation, packaging of irradiated food, food irradiation standards and regulations, history of food irradiation, and communication aspects.

Fruit irradiation

International Nuclear Information System (INIS)

Anon.

1977-01-01

Food spoilage is a common problem when marketing agricultural products. Promising results have already been obtained on a number of food irradiating applications. A process is described in this paper where irradiation of sub-tropical fruits, especially mangoes and papayas, combined with conventional heat treatment results in effective insect and fungal control, delays ripening and greatly improves the quality of fruit at both export and internal markets

Comparative study on disinfection potency of spore forming bacteria by electron-beam irradiation and gamma-ray irradiation

International Nuclear Information System (INIS)

Takizawa, Hironobu; Suzuki, Satoru; Suzuki, Tetsuya; Takama, Kozo; Hayashi, Toru; Yasumoto, Kyoden.

1990-01-01

Along with gamma-ray irradiation, electron-beam irradiation (EB) is a method to disinfect microorganisms which cause food decomposition and food-poisoning. The present study was undertaken to compare sterilization efficacy of EB and gamma-ray irradiation on bacterial spores and vegetative cells under various conditions. Spores of Bacillus pumilus, a marker strain for irradiation study, and Bacillus stearothermophilus known as a thermophilic bacteria were irradiated by electron-beam and gamma-ray separately at irradiation dose of 0 to 10 kGy on combination of wet/dry and aerobic/anaerobic conditions. Sterilization effect of irradiation on spores was evaluated by colony counting on agar plates. Results showed that both EB and gamma-ray irradiation gave sufficient sterilization effect on spores, and the sterilization effect increased exponentially with irradiation dose. The sterilization effect of gamma-ray irradiation was higher than that of EB in all cases. Higher disinfection effect was observed under aerobic condition. The present study suggests that oxygen supply in EB is more important than gamma-ray irradiation. No results suggesting that chlorine ion at 0.1 ppm (as available chlorine concentration) enhanced the sterilization efficacy of either EB or gamma-ray irradiation was obtained under any conditions examined. (author)

Comparative study on disinfection potency of spore forming bacteria by electron-beam irradiation and gamma-ray irradiation

Energy Technology Data Exchange (ETDEWEB)

Takizawa, Hironobu; Suzuki, Satoru; Suzuki, Tetsuya; Takama, Kozo [Hokkaido Univ., Hakodate (Japan). Faculty of Fisheries; Hayashi, Toru; Yasumoto, Kyoden

1990-10-01

Along with gamma-ray irradiation, electron-beam irradiation (EB) is a method to disinfect microorganisms which cause food decomposition and food-poisoning. The present study was undertaken to compare sterilization efficacy of EB and gamma-ray irradiation on bacterial spores and vegetative cells under various conditions. Spores of Bacillus pumilus, a marker strain for irradiation study, and Bacillus stearothermophilus known as a thermophilic bacteria were irradiated by electron-beam and gamma-ray separately at irradiation dose of 0 to 10 kGy on combination of wet/dry and aerobic/anaerobic conditions. Sterilization effect of irradiation on spores was evaluated by colony counting on agar plates. Results showed that both EB and gamma-ray irradiation gave sufficient sterilization effect on spores, and the sterilization effect increased exponentially with irradiation dose. The sterilization effect of gamma-ray irradiation was higher than that of EB in all cases. Higher disinfection effect was observed under aerobic condition. The present study suggests that oxygen supply in EB is more important than gamma-ray irradiation. No results suggesting that chlorine ion at 0.1 ppm (as available chlorine concentration) enhanced the sterilization efficacy of either EB or gamma-ray irradiation was obtained under any conditions examined. (author).

Effect of neutron irradiation and post-irradiation annealing on microstructure and mechanical properties of OFHC-copper

International Nuclear Information System (INIS)

Singh, B.N.; Edwards, D.J.; Toft, P.

2001-01-01

Specimens of oxygen-free high conductivity (OFHC) copper were irradiated in the DR-3 reactor at Risoe at 100 deg. C to doses in the range 0.01-0.3 dpa (NRT). Some of the specimens were tensile tested in the as-irradiated condition at 100 deg. C whereas others were given a post-irradiation annealing treatment at 300 deg. C for 50 h and subsequently tested at 100 deg. C. The microstructure of specimens was characterized in the as-irradiated as well as irradiated and annealed conditions both before and after tensile deformation. While the interstitial loop microstructure coarsens with irradiation dose, no significant changes were observed in the population of stacking fault tetrahedra (SFT). The post-irradiation annealing leads to only a partial recovery and the level of recovery depends on the irradiation dose level. However, the post-irradiation annealing eliminates the yield drop and reinstates enough uniform elongation to render the material useful again. These results are discussed in terms of the cascade-induced source hardening (CISH) model

Effect of neutron irradiation and post-irradiation annealing on microstructure and mechanical properties of OFHC-copper

Energy Technology Data Exchange (ETDEWEB)

Singh, B.N. E-mail: bachu.singh@risoe.dk; Edwards, D.J.; Toft, P

2001-12-01

Specimens of oxygen-free high conductivity (OFHC) copper were irradiated in the DR-3 reactor at Risoe at 100 deg. C to doses in the range 0.01-0.3 dpa (NRT). Some of the specimens were tensile tested in the as-irradiated condition at 100 deg. C whereas others were given a post-irradiation annealing treatment at 300 deg. C for 50 h and subsequently tested at 100 deg. C. The microstructure of specimens was characterized in the as-irradiated as well as irradiated and annealed conditions both before and after tensile deformation. While the interstitial loop microstructure coarsens with irradiation dose, no significant changes were observed in the population of stacking fault tetrahedra (SFT). The post-irradiation annealing leads to only a partial recovery and the level of recovery depends on the irradiation dose level. However, the post-irradiation annealing eliminates the yield drop and reinstates enough uniform elongation to render the material useful again. These results are discussed in terms of the cascade-induced source hardening (CISH) model.

Effect of neutron irradiation and post-irradiation annealing on microstructure and mechanical properties of OFHC-copper

Science.gov (United States)

Singh, B. N.; Edwards, D. J.; Toft, P.

2001-12-01

Specimens of oxygen-free high conductivity (OFHC) copper were irradiated in the DR-3 reactor at Risø at 100 °C to doses in the range 0.01-0.3 dpa (NRT). Some of the specimens were tensile tested in the as-irradiated condition at 100 °C whereas others were given a post-irradiation annealing treatment at 300 °C for 50 h and subsequently tested at 100 °C. The microstructure of specimens was characterized in the as-irradiated as well as irradiated and annealed conditions both before and after tensile deformation. While the interstitial loop microstructure coarsens with irradiation dose, no significant changes were observed in the population of stacking fault tetrahedra (SFT). The post-irradiation annealing leads to only a partial recovery and the level of recovery depends on the irradiation dose level. However, the post-irradiation annealing eliminates the yield drop and reinstates enough uniform elongation to render the material useful again. These results are discussed in terms of the cascade-induced source hardening (CISH) model.

Food package irradiator-a landmark of operational safety and food irradiation research

International Nuclear Information System (INIS)

Jain, M.P.; Sanyal, Bhaskar; Ghosh, Sunil K.

2017-01-01

Food irradiation in India has been undertaken for preservation of food for safe consumption, security of food for round the year and export of the food commodities to earn foreign exchange. Therefore, an irradiation plant known as Food Package Irradiator (FPI) was set-up in the year 1967 in BARC. This plant utilizes gamma radiation from "6"0Co source that has a maximum allowable activity of 100 kCi. It is a multipurpose facility where a wide range of products like onion for sprout inhibition to spices for microbial decontamination can be carried out. In short, the design of irradiator has been considered based on obtaining variable throughputs and variable dose rates

Heavy ion irradiation induces autophagy in irradiated C2C12 myoblasts and their bystander cells

International Nuclear Information System (INIS)

Hino, Mizuki; Tajika, Yuki; Hamada, Nobuyuki

2010-01-01

Autophagy is one of the major processes involved in the degradation of intracellular materials. Here, we examined the potential impact of heavy ion irradiation on the induction of autophagy in irradiated C2C12 mouse myoblasts and their non-targeted bystander cells. In irradiated cells, ultrastructural analysis revealed the accumulation of autophagic structures at various stages of autophagy (id est (i.e.) phagophores, autophagosomes and autolysosomes) within 20 min after irradiation. Multivesicular bodies (MVBs) and autolysosomes containing MVBs (amphisomes) were also observed. Heavy ion irradiation increased the staining of microtubule-associated protein 1 light chain 3 and LysoTracker Red (LTR). Such enhanced staining was suppressed by an autophagy inhibitor 3-methyladenine. In addition to irradiated cells, bystander cells were also positive with LTR staining. Altogether, these results suggest that heavy ion irradiation induces autophagy not only in irradiated myoblasts but also in their bystander cells. (author)

Food irradiation: contaminating our food

International Nuclear Information System (INIS)

Piccioni, R.

1988-01-01

The nuclear industry has promoted food irradiation as an effective and safe means of preserving food at minimum risk to the public. However, wide-scale food irradiation programmes such as that approved in the United States of America would have an adverse impact on public health in the following ways: through the consumption of carcinogenic substances generated in irradiated foods, through the use of irradiation to mask bacteriological contamination of spoiled food, through the replacement of fresh foods with nutritionally depleted foods, through accidents with leaks or mishandling of the radiation sources used and through the environmental damage resulting from reactor operation or spent fuel reprocessing necessary to produce the required isotopes for food irradiation. The food irradiation market is potentially enormous, requiring a large number of facilities and isotopes, some, such as caesium-137, would come from the production of nuclear weapons. Evidence of the presence of carcinogenic or mutagenic activity in irradiated foods is discussed. Although the US Federal Drug Administration (FDA) has approved a food irradiation programme it would actually be against the FDA's legal obligation which is to protect the health and safety of the American people. (UK)

Integrity Assessment of HANARO Irradiation Capsule for Long-Term Irradiation Testing

Energy Technology Data Exchange (ETDEWEB)

Choo, Kee Nam; Cho, Man Soon; Yang, Sung Woo; Shin, Yoon Taek; Park, Seng Jae; Yang, Tae Ho; Jun, Byung Hyuk; Kim, Myong Seop [KAERI, Daejeon (Korea, Republic of); Hong, Sang Hyun [Chungnam University, Daejeon (Korea, Republic of)

2016-05-15

The capsule technology was basically developed for irradiation testing under a commercial reactor operation environment. Most irradiation testing using capsules has been performed at around 300 .deg. C within four reactor operation cycles (about 100 days equivalent to 1.5 dpa (displacement for atom)) at HANARO. Based on the accumulated experience as well as the sophisticated requirements of users, HANARO has recently been required to support national R and D projects requiring much higher neutron fluence. To scope the user requirements for higher neutron irradiation fluence, several efforts using an instrumented capsule have been applied at HANARO. In this paper, the applied stresses on the capsule are estimated because the capsule was suspected to be susceptible to fatigue failure during irradiation testing. In addition, the on-going design improvements of the irradiation capsule for higher neutron irradiation fluence at HANARO are described. The applied stresses on the rod tip were analyzed using the ANSYS program. The applied stresses on the rod tip can be classified into stresses by the designed bottom spring, by the upward flowing coolant, by the capsule vibration, and by the welding residual stress. The maximal stresses due to the first three factors were estimated as 5.4 MPa, 132.9 MPa, and 161 MPa, respectively. These stresses do not exceed the known fatigue strength of stainless steels (∼300 MPa). Residual stress by welding is another possible stress and it is known to occur at up to about 300 MPa.

Food irradiation development: Malaysian perspective

International Nuclear Information System (INIS)

Zainon Othman

1997-01-01

Malaysia recognised the potential of food irradiation as a technology that can contribute to solving some preservation problems associated with local agricultural produce. Research studies in this technology were initiated in late 1970s and since 1985, all activities pertaining to R and D applications, adoption and technology transfer of food irradiation were coordinated by The National Working Committee on Food Irradiation which comprises of members from research institutes, universities, regulatory agencies and consumer association. To date, technical feasibility studies conducted on 7 food items / agricultural commodities of economic importance demonstrated the efficacy of irradiation in extending shelf-life, improving hygienic quality and overcoming quarantine barriers in trade. Presently, 1 multipurpose Co-60 irradiator (I MCi), 2 gammacells and an electron beam machine (3 MeV) are available at MINT for research and commercial runs. The Malaysian Standards on Guidelines for Irradiation of Food was formulated in 1992 to facilitate application by local food industries. However, Malaysia has not yet commercially adopt the technology. Among many factors contributing to the situation is the apparent lack of interest by food industries and consumers. Consumer attitude study indicated majority of consumers are still unaware of the benefits of the technology and expressed concern for the safety of process and irradiated products due to limited knowledge and adverse publicity by established consumer groups. Although the food processors indicate positive attitude towards food irradiation, there remain many factors delaying its commercial application such as limited knowledge, cost-benefit, logistics and consumer acceptance. On the regulatory aspect, approval is required from the Director-General of Ministry of Health prior to application of irradiation on food and sale of irradiated food but efforts are being geared towards approving irradiation of certain food

The wholesomeness of irradiated food

International Nuclear Information System (INIS)

Elias, P.S.

1976-01-01

The acceptance of food irradiation as a safe process of preservation by national authorities concerned with the safety of foodstuffs has hitherto made slow progress. The technology has existed for some 25 years but the general attitude towards official acceptance of the process has been marred by irrational and unscientific fears. As may have been mentioned by previous speakers,'the basic process of food irradiation does not differ in the physical sense from any other food processing techniques which involve the application of radiation energy to food. The energy level used in food irradiation is too low ever to lead to any production of radioactivity in the irradiated food, hence wholesomeness considerations can totally exclude this aspect. The uniqueness of food irradiation rests inherently on the particular type of energy employed and has aroused special attention because of this fact. The wholesomeness of food treated by heat or microwaves has not been questioned to the same extent, yet the very same question has been raised in relation to treatment by gamma rays and electron beams. Being a new process it requires not only a toxicological but also a microbiological as well as nutritional approach to the assessment of the wholesomeness of irradiated food. Studies on the radiation chemistry of proteins, lipids and carbohydrates, the main constituents of foods, when irradiated in the Mrad range, have yielded information which shows that these substances react in a reasonably uniform manner to irradiation. Many of the irradiation-induced compounds identified in irradiated foods can also be found in various non-irradiated foods. For those products that have been identified, the quantities found are in the parts per million range or less. Available data on the structures of radiation chemical products in food and the very low concentrations at which they occur, suggest the general conclusion that the health hazard they might represent is negligible

Food irradiation: advantages and limitations

International Nuclear Information System (INIS)

Hernandes, N.K.; Vital, H. de C.; Sabaa-Srur, A.U.O.

2003-01-01

Food irradiation is a physical method of processing food (e.g. freezing, canning). It has been thoroughly researched over the last four decades and is recognized as a safe and wholesome method. It has the potential both of disinfesting dried food to reduce storage losses and disinfesting fruits and vegetables to meet quarantine requirements for export trade. Low doses of irradiation inhibit spoilage losses due to sprouting of root and tuber crops. Food- borne diseases due to contamination by pathogenic microorganisms and parasites of meat, poultry, fish, fishery products and spices are on the increase. Irradiation of these solid foods can decontaminate them of pathogenic organisms and thus provide safe food to the consumer. Irradiation can successfully replace the fumigation treatment of cocoa beans and coffee beans and disinfest dried fish, dates, dried fruits, etc. One of the most important advantages of food irradiation processing is that it is a coldprocess which does not significantly alter physico-chemical characters of the treated product. It can be applied to food after its final packaging. Similar to other physical processes of food processing, (e.g. canning, freezing), irradiation is a capital intensive process. Thus, adequate product volume must be made available in order to maximize the use of the facility and minimize the unit cost of treatment. Lack of harmonization of regulations among the countries which have approved irradiated foods hampers the introduction of this technique for international trade. Action at the international level has to be taken in order to remedy this situation. One of the important limitations of food irradiation processing is its slow acceptance by consumers, due inter alia to a perceived association with radioactivity. The food industry tends to be reluctant to use the technology in view of uncertainties regarding consumer acceptance of treated foods. Several market testing and consumer acceptance studies have been carried

Comparison of electron-irradiation and gamma-irradiation as a decontamination treatment of spices

International Nuclear Information System (INIS)

Hayashi, Toru; Todoriki, Setsuko; Mamun.

1993-01-01

Electron-irradiation at 10 kGy decontaminated all the eight kinds of spices (black pepper, white pepper, nutmeg, red pepper, parsley, paprika, laurel and onion powder) to the microbial levels lower than 10 2 /g. Similar sterilization effects by the irradiation were observed on heat-resistant bacterial spores. The 10 kGy irradiation did not significantly affect the contents of essential oils and colors of the spices. These results indicate that electron-irradiation at 10 kGy effectively decontaminates spices without notable adverse effect on the qualities. The disinfecting effect of electron beams on spices was smaller than that of gamma-rays. (author)

International document on food irradiation

International Nuclear Information System (INIS)

1990-06-01

This international document highlights the major issues related to the acceptance of irradiated food by consumers, governmental and intergovernmental activities, the control of the process, and trade. The conference recognized that: Food irradiation has the potential to reduce the incidence of foodborne diseases. It can reduce post-harvest food losses and make available a larger quantity and a wider variety of foodstuffs for consumers. Regulatory control by competent authorities is a necessary prerequisite for introduction of the process. International trade in irradiated foods would be facilitated by harmonization of national procedures based on internationally recognized standards for the control of food irradiation. Acceptance of irradiated food by the consumer is a vital factor in the successful commercialization of the irradiation process, and information dissemination can contribute to this acceptance

Food irradiation scenario in India

International Nuclear Information System (INIS)

Thomas, Paul

1998-01-01

Over 3 decades of research and developmental effort in India have established the commercial potential for food irradiation to reduce post-harvest losses and to ensure food safety. Current regulations permit irradiation of onions, potatoes and spices for domestic consumption and operation of commercial irradiators for treatment of food. In May 1997 draft rules have been notified permitting irradiation of several additional food items including rice, wheat products, dry fruits, mango, meat and poultry. Consumers and food industry have shown a positive attitude to irradiated foods. A prototype commercial irradiator for spices set up by Board of Radiation and Isotope Technology (BRIT) is scheduled to commence operation in early 1998. A commercial demonstration plant for treatment of onions is expected to be operational in the next 2 years in Lasalgaon, Nashik district. (author)

Food irradiation: chemistry and applications

International Nuclear Information System (INIS)

Thakur, B.R.; Singh, R.K.

1994-01-01

Food irradiation is one of the most extensively and thoroughly studied methods of food preservation. Despite voluminous data on safety and wholesomeness of irradiated foods, food irradiation is still a “process in waiting.” Although some countries are allowing the use of irradiation technology on certain foods, its full potential is not recognized. Only 37 countries worldwide permit the use of this technology. If used to its full potential, food irradiation can save millions of human lives being lost annually due to food‐borne diseases or starvation and can add billions of dollars to the world economy. This paper briefly reviews the history and chemistry of food irradiation along with its main applications, impediments to its adoption, and its role in improving food availability and health situation, particularly in developing countries of the world

Origin of irradiations by ionizing radiations

International Nuclear Information System (INIS)

Metivier, H.

1998-01-01

Irradiations by ionizing radiations proceed from two main sources: the natural radiations from the environment and the sources of 'human' origin, i.e. linked with modern technology. In most countries the irradiation by natural sources remains the most important. The irradiations for medical purposes comes in second position and depends on the degree of technological evolution of the country, and in the last position are the irradiations linked with nuclear industry. The inventory of these irradiations is regularly updated by the Scientific Committee of the United Nations for the study of ionizing radiation effects (UNSCEAR). In France the mean individual irradiation due to natural radioactivity is of 2 mSv per year of efficient dose and can vary with a factor 3 from one region to the other. Irradiation of medical diagnosis origin is of about 1 mSv per year. This paper presents successively: the natural irradiation sources (cosmic radiation, cosmic rays and cosmogenic radionuclides, the Earth's radiations, primary radionuclides and radon), the natural sources modified by the technology (extraction industries, fossil fuels and phosphated ores, aerial transports and space activities, consumer products), the irradiation sources of technological origin (nuclear weapons, electric power production, major accidents, occupational irradiations), and the medical irradiations (diagnosis techniques, radiology, nuclear medicine and therapeutic uses). (J.S.)

Damage study of an austenitic stainless steel in high cycle multiaxial fatigue regime;Etude de l'endommagement d'un acier inoxydable austenitique par fatigue multiaxiale a grand nombre de cycles

Energy Technology Data Exchange (ETDEWEB)

Poncelet, M. [CEA Saclay, DEN, SRMA, 91 - Gif-sur-Yvette (France); Barbier, G.; Raka, B.; Vincent, L.; Desmorat, R. [LMT Cachan, ENS Cachan/CNRS/UPMC/PRES Univ. Sud Paris, 94 - Cachan (France); Barbier, G. [EDF R and D / LaMSID, 92 - Clamart (France)

2010-02-15

Biaxial fatigue tests are performed up to 1 000 000 cycles at room temperature. Cross specimens of 304L steel thinned in their centre to initiate crack, are loaded by a biaxial testing machine. The strain at the centre of the sample is measured during loading using a stroboscopic Digital Image Correlation (DIC) technique, and crack initiation on the whole gauge zone is early detected by a second DIC-based measurement. A special optical assembly is designed to allow for simultaneous measurements. Three types of loadings are performed: equi-biaxial with a loading ratio R = 0.1, equi-biaxial with loading ratio R = -1, pseudo uniaxial (cyclic loading at R 0.1 in one direction and constant loading in the other). First results are commented. (authors)

Antibacterial activity of irradiated and non-irradiated chitosan and chitosan derivatives against Escherichia coli growth

International Nuclear Information System (INIS)

Tg Ahbrizal Farizal Tg Ahmad; Norimah Yusof; Kamarudin Bahari; Kamaruddin Hashim

2006-01-01

Samples of chitosan and four chitosan derivatives [ionic chitosan, chitosan lactate, carboxymethyl chitosan (C) and carboxymethyl chitosan (L)] were studied for their antibacterial activities against Escherichia coli growth. Chitosan and chitosan derivatives were prepared at concentrations 20, 100, 1000, 10000 ppm and 250, 1000, 5000, 10000, 20000 ppm, respectively. Each of the samples was tested before and after irradiation with electron beam at 25 kGy. The turbidity of bacterial growth media was measured periodically at 0, 0.5, 1, 2, 4, 6 and 24 h after inoculation using the optical density method. The results indicated that non- irradiated chitosan inhibited E. coli growth at 20 and 100 ppm. Meanwhile, irradiated chitosan at 100 and 1000 ppm concentration inhibited E. coli growth. Both irradiated and non-irradiated ionic chitosan inhibited E. coli growth at all concentrations used. Chitosan lactate was found to inhibit E. coli at concentration as low as 5000 ppm for both irradiated and non-irradiated samples. E. coli growth was not inhibited by carboxymethyl chitosan (C) and carboxymethyl chitosan (L), before and after irradiation. The findings suggested that chitosan has greater antibacterial activity as compared to the chitosan derivative samples. (Author)

Food irradiation in Malaysia

International Nuclear Information System (INIS)

Mohd Ghazali Hj Abd Rahman.

1985-01-01

Food irradiation has recently been visited as a technology that can contribute to the solution of problems associated with food preservation of Malaysia's agriculture produce and products thereby improving the economic status of the rural sector. However, the history of food irradiation in Malaysia is very recent. Research carried out on food irradiation only began in 1974 as a result of the installation of a 60 Co facility (initially 10,000 Ci) at the National University of Malaysia. Since its installation several studies have been carried out pertaining to the food irradiation. Presently its development has been slow. Research in this area has been confined to laboratory scale and purely academic. This limitation is due to a number of reasons, among others are: a) limited number of facilities; b) lack of expertise to conduct its research; c) other preservation methods can be improved with lower capital output. An important step towards its development was made when Malaysia actively participated in the RCA/IAEA food irradiation project, viz. the irradiation of pepper which was carried out at the National University of Malaysia in the 80's. As a result of this venture, research and development activities in food irradiation have been geared toward semi-plot scale with the view ot commercialization in the future. In 1982, a group of researchers was formed to conduct feasibility studies using irradiation techniques in trying to overcome several problems associated with our local paddy and rice. Another group is being organized by the National University of Malaysia to look into the problems associated with the preservation of frozen shrimps. (author)

Irradiating strand material

International Nuclear Information System (INIS)

Austin, J.R.; Brown, M.J.; Loan, L.D.

1975-01-01

Conductors covered with insulation which is to be irradiated are passed between two groups of coaxial sheaves mounted rotatably individually. Successive sections of the conductors are advanced past the window of one accelerator head, around the associated sheave or sheaves, and then past the window of another accelerator head. The accelerators face in substantially opposite directions and are staggered along the paths of the conductors to avoid any substantial overlap of the electron beams associated therewith. The windows extend vertically to encompass all the generally horizontal passes of the conductors as between the two groups of sheaves. Preferably, conductors are strung-up between the sheaves in a modified figure eight pattern. The pattern is a figure eight modified to intermittently include a pass between the sheaves which is parallel to a line joining the axes of the two groups of sheaves. This reverses the direction of travel of the conductors and optimizes the uniformity of exposure of the cross sectional area of the insulation of the conductors to irradiation. The use of a figure eight path for the conductors causes the successive sections of the conductor to turn about the longitudinal axes thereof as they are advanced around the sheaves. In this way the insulation is more uniformly irradiated. In a preferred embodiment, twisted conductor pairs may be irradiated. The twist accentuates the longitudinal turning of the conductor pair. The irradiation of twisted pairs achieves obvious manufacturing economies while avoiding the necessity of having to twist irradiation cross-linked conductors

Preliminary irradiation test results from the Yankee Atomic Electric Company reactor vessel test irradiation program

International Nuclear Information System (INIS)

Biemiller, E.C.; Fyfitch, Stephen; Campbell, C.A.

1994-01-01

The Yankee Atomic Electric Company test irradiation program was implemented to characterize the irradiation response of representative Yankee Rowe reactor vessel beltline plate materials and to remove uncertainties in the analysis of existing irradiation data on the Yankee Rowe reactor vessel steel. Plate materials each containing 0.24 w/o copper, but different nickel contents at 0.63 w/o and 0.19 w/o, were heat treated to simulate the Yankee vessel heat treatment (austenitized at 982 o C (1800 o F)) and to simulate Regulatory Guide 1.99 database materials (austenitized at 871 o C (1600 o F)). These heat treatments produced different microstructures so the effect of microstructure on irradiation damage sensitivity could be tested. Because the nickel content of the test plates varied and the copper level was constant, the effect of nickel on irradiation embrittlement was also tested. Correlation monitor material, HSST-02, was included in the program to benchmark the Ford Nuclear Reactor (University of Michigan Test Reactor) which had never been used before for this type of irradiation program. Materials taken from plate surface locations (versus 1/4 T) were included to test whether or not the improved toughness properties of the plate surface layer, resulting from the rapid quench, are maintained after irradiation. If the improved properties are maintained, pressurized thermal shock calculations could utilize this margin. Finally, for one experiment, irradiations were conducted at two irradiation temperatures (260 o C and 288 o C) to determine the effect of irradiation temperature on embrittlement. (Author)

Fluorescence of irradiated hydrocarbons

International Nuclear Information System (INIS)

Gulis, I.G.; Evdokimenko, V.M.; Lapkovskij, M.P.; Petrov, P.T.; Gulis, I.M.; Markevich, S.V.

1977-01-01

A visible fluorescence has been found out in γ-irradiated aqueous of carbohydrates. Two bands have been distinguished in fluorescence spectra of the irradiated solution of dextran: a short-wave band lambdasub(max)=140 nm (where lambda is a wave length) at lambdasub(β)=380 nm and a long-wave band with lambdasub(max)=540 nm at lambdasub(β)=430 nm. A similar form of the spectrum has been obtained for irradiated solutions of starch, amylopectin, lowmolecular glucose. It has been concluded that a macromolecule of polysaccharides includes fluorescent centres. A relation between fluorescence and α-oxiketon groups formed under irradiation has been pointed out

Do you know 'food irradiation'?. A survey of consumer status toward food irradiation in Japan

International Nuclear Information System (INIS)

Furuta, Masakazu

1998-01-01

In Japan potatoes have been irradiated for the purpose of sprout inhibition for more than 20 years and more than ten thousand irradiated potatoes are circulated in Japanese market in recent years. Nevertheless, there are few surveys about the consumer status toward food irradiation in Japan. We have been held 'Radiation Fair -- The relationship between daily life and radiation--' during summer vacation season in August for more than 10 years in Osaka, the largest city of western Japan, for the purpose of public education and information transfer of radiation and radiation-related technology especially to school kids. We displayed 200 kg of irradiated potatoes together with explanatory panels. We distributed questionnaires to the senior high school students (16 years old) and upward visitor for recent 3 years to inquire their status toward radiation and irradiated products including irradiated potatoes as well as impression toward the displays. According to the survey results in 1997, the ratio of respondents who had heard of irradiated potatoes was 51% of 228 answers. This value was smaller than those of the Gallop survey conducted in the United States (73%). After viewing the display and description of irradiated potatoes, almost half of the respondents indicated a positive feeling for tasting the irradiated potatoes. Most of the respondents chose one of the following issues, Freshness' (37%), 'Open date' (13%), or 'Food additives' (34%) as the major concerns about food safety. Interestingly, 'Pesticide' and/or 'Foodborne pathogen' highly were chosen by only 15% of the respondents in total even though these issue were highly ranked in the US surveys. These results indicate that original methodology is necessary for distributing the information related food irradiation related food irradiation efficiently. (J.P.N)

Effect of irradiation temperature on microstructural changes in self-ion irradiated austenitic stainless steel

Science.gov (United States)

Jin, Hyung-Ha; Ko, Eunsol; Lim, Sangyeob; Kwon, Junhyun; Shin, Chansun

2017-09-01

We investigated the microstructural and hardness changes in austenitic stainless steel after Fe ion irradiation at 400, 300, and 200 °C using transmission electron microscopy (TEM) and nanoindentation. The size of the Frank loops increased and the density decreased with increasing irradiation temperature. Radiation-induced segregation (RIS) was detected across high-angle grain boundaries, and the degree of RIS increases with increasing irradiation temperature. Ni-Si clusters were observed using high-resolution TEM in the sample irradiated at 400 °C. The results of this work are compared with the literature data of self-ion and proton irradiation at comparable temperatures and damage levels on stainless steels with a similar material composition with this study. Despite the differences in dose rate, alloy composition and incident ion energy, the irradiation temperature dependence of RIS and the size and density of radiation defects followed the same trends, and were very comparable in magnitude.

Practical design of gamma irradiation facility

International Nuclear Information System (INIS)

Sugimoto, Sen-ichi

1976-01-01

In this report, it is intended to describe mainly the multi-purpose irradiation facilities which carry out the consigned irradiation for the sterilization of medical apparatuses, which is most of the demand of gamma irradiation in Japan. Gamma irradiation criterion is summed up to that ''Apply the specified dose properly and uniformly to product cases and be economic.'' Though the establishment of the design standard for irradiation facilities is not easy and is not solve simply, the factors to be considered in the design are as follows: (1) mechanism safety, (2) multipurpose irradiation structure, (3) irradiation criteria and practice, (4) efficiency of radiation source utilization and related problems, and (5) economical merit. Irradiation facilities are generally itemized as follows: irradiation equipments, radiation source-storing facility, package carrier, radiation source-driving equipments, facilities for safety and operational management and others. Examples and their characteristics are reported for the facilities of Japan Radio-isotope Irradiation Cooperative Association and Radie Industries Ltd. Expenses for construction, processing and radiation sources are shown on the basis of a few references, and the cost trially calculated under a certain presumptive condition is given. (Wakatsuki, Y.)

Identification of irradiated chicken

International Nuclear Information System (INIS)

Spiegelberg, A.; Heide, L.; Boegl, K.W.

1990-01-01

Frozen chicken and chicken parts were irradiated at a dose of 5 kGy with Co-60. The irradiated chicken and chicken parts were identified by determination of three radiation-induced hydrocarbons from the lipid fraction. Isolation was carried out by high-vacuum distillation with a cold-finger apparatus. The detection of the hydrocarbons was possible in all irradiated samples by gaschromatography/mass spectrometry. (orig.) [de

Irradiation - who needs it?

International Nuclear Information System (INIS)

Scoular, C.

1994-01-01

In this paper the public's attitudes to the irradiation of food to ensure it is bacteria free and to prolong shelf-life are considered. The need to label irradiated food and to educate the public about its implications are emphasised. The opinions of the large food retailers who maintain that high standards in food processing, hygiene and refrigeration eliminate the need for food irradiation are discussed. (UK)

Investigation of food irradiation technology for application to plant quarantine. Working group report of food irradiation technology

Energy Technology Data Exchange (ETDEWEB)

Sunaga, Hiromi; Ito, Hitoshi; Takatani, Yasuyuki; Takizawa, Haruki; Yotsumoto, Keiichi; Tanaka, Ryuichi [Japan Atomic Energy Research Inst., Takasaki, Gunma (Japan). Takasaki Radiation Chemistry Research Establishment; Hirano, Tsuyoshi; Tokunaga, Okihiro

1999-06-01

The commercialization of food irradiation in Japan was started in 1973 for the sprout inhibition of potatoes as the first successful food irradiation facility in the world. Since approval of potato irradiation, no items has been commercialized in Japan. However, international agreement for phase out of methyl bromide after 2005 and increasing incidences of foodborn diseases such as by Escherichia coli O157:H7 are forcing to have interesting to food irradiation. Takasaki Radiation Chemistry Research Establishment has long experiences on research of irradiation effect and engineering of food irradiation in Japan. From these back ground, working group of food irradiation was organized at August 1997 by some members of Department of Radiation Research for Environment and Resources and Advanced Technology Center for supporting technically on commercialization of food irradiation. This report presents the result of discussion in working group on generalization up to date researches of food irradiation, application fields and items, technical problems and future prospects of this technology in Japan. (author)

Apparatus for irradiation with electron beam

International Nuclear Information System (INIS)

Uehara, K.; Ito, A.; Nishimune, K.; Fujita, K.

1976-01-01

An irradiation apparatus with high energy electrons is disclosed in which a wire shaped or linear object to be irradiated is moved back and forth many times under an electron window so as to irradiate it with an electron beam. According to one feature of the invention, an electron beam, which leaks through gaps between the objects to be irradiated or which penetrates the objects to be irradiated, is reversed by a magnetic field approximately perpendicular to the scanning face of the electron beam by means of a magnet which is disposed under the objects to be irradiated, and the reversed electron beam is thereby again applied to the objects to be irradiated. A high utilization rate of the electron beam is accomplished, and the objects can be thereby uniformly irradiated with the electron beam. 4 claims, 6 drawing figures

Dose distribution of non-coplanar irradiation

Energy Technology Data Exchange (ETDEWEB)

Fukui, Toshiharu; Wada, Yoichi; Takenaka, Eiichi

1987-02-01

Non-coplanar irradiations were applied to the treatment of brain tumor. The dose distribution around the target area due to non-coplanar irradiation was half less than the dose when coplanar irradiation used. Integral volume dose due to this irradiation was not always less than that due to conventional opposing or rotational irradiation. This irradiation has the better application to the following;as a boost therapy, glioblastoma multiforme;as a radical therapy, recurrent brain tumor, well differentiated brain tumor such as craniopharyngioma, hypophyseal tumor etc and AV-malformation.

Societal benefits of food irradiation

International Nuclear Information System (INIS)

Prakash, Anuradha

2013-01-01

Food irradiation has a direct impact on society by reducing the occurrence of food-borne illness, decreasing food spoilage and waste, and facilitating global trade. Food irradiation is approved in 40 countries around the world to decontaminate food of disease and spoilage causing microorganisms, sterilize insect pests, and inhibit sprouting. A recent estimate suggests that 500,000 metric of food is currently irradiated worldwide, primarily to decontaminate spices. Since its first use in the 1960s the use of irradiation for food has grown slowly, but it remains the major technology of choice for certain applications. The largest growth sector in recent years has been phytosanitary irradiation of fruit to disinfest fruit intended for international shipment. For many countries which have established strict quarantine standards, irradiation offers as an effective alternative to chemical fumigants some of which are being phased out due to their effects on the ozone layer. Insects can be sterilized at very low dose levels, thus quality of fruit can be maintained. Irradiation is also highly effective in destroying microbial pathogens such as Salmonella spp., E. coli, and Listeria, hence its application for treatment of spices, herbs, dried vegetables, frozen seafood, poultry, and meat and its contribution to reducing foodborne illnesses. Unfortunately the use of irradiation for improving food safety has been under-exploited. This presentation will provide details on the use, benefits, opportunities, and challenges of food irradiation. (author)

Consumer attitude toward food irradiation

International Nuclear Information System (INIS)

Bruhn, C.M.M.

1986-01-01

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

Phytosanitary irradiation - Development and application

Science.gov (United States)

Hallman, Guy J.; Loaharanu, Paisan

2016-12-01

Phytosanitary irradiation, the use of ionizing radiation to disinfest traded agricultural commodities of regulated pests, is a growing use of food irradiation that has great continued potential for increase in commercial application. In 2015 approximately 25,000 t of fresh fruits and vegetables were irradiated globally for phytosanitary purposes. Phytosanitary irradiation has resulted in a paradigm shift in phytosanitation in that the final burden of proof of efficacy of the treatment has shifted from no live pests upon inspection at a port of entry (as for all previous phytosanitary treatments) to total dependence on certification that the treatment for target pests is based on adequate science and is commercially conducted and protected from post-treatment infestation. In this regard phytosanitary irradiation is managed more like a hazard analysis and critical control point (HACCP) approach more consistent with food safety than phytosanitation. Thus, phytosanitary irradiation offers a more complete and rigorous methodology for safeguarding than other phytosanitary measures. The role of different organizations in achieving commercial application of phytosanitary irradiation is discussed as well as future issues and applications, including new generic doses.

Irradiation of fruit and vegetables

International Nuclear Information System (INIS)

O'Beirne, David

1987-01-01

There is likely to be less economic incentive to irradiate fruits and vegetables compared with applications which increase the safety of foods such as elimination of Salmonella or decontamination of food ingredients. Of the fruit and vegetable applications, irradiation of mushrooms may offer the clearest economic benefits in North-Western Europe. The least likely application appears to be sprout inhibition in potatoes and onions, because of the greater efficiency and flexibility of chemical sprout inhibitors. In the longer-term, combinations between irradiation/MAP/other technologies will probably be important. Research in this area is at an early stage. Consumer attitudes to food irradiation remain uncertain. This will be a crucial factor in the commercial application of the technology and in the determining the balance between utilisation of irradiation and of technologies which compete with irradiation. (author)

Longevity of irradiated burros

International Nuclear Information System (INIS)

Lushbaugh, C.C.; Brown, D.G.; Frome, E.L.

1986-01-01

During the course of external radiation exposures of burros to establish a dose-response curve for acute mortality after total irradiation, some of the animals at the three lowest exposures to gamma photons survived. These groups of 10, 9, and 10 burros were exposed to 320, 425, and 545 R, respectively. There were 10 unirradiated controls. In 1953, 20 burros were exposed to 375 R (gamma) in 25-R/week increments without acute mortality and were added to the life-span study. In 1957, 33 burros were exposed to mixed neutron-gamma radiation from nuclear weapons, and 14 controls were added. The total number of irradiated burros in the study was increased to 88 by the addition of 6 animals irradiated with 180 rads of neutron and gamma radiation (4:1) in a Godiva-type reactor in 1959. In this experiment two acute deaths occurred which were not included in the analysis. In the first 4 years after the single gamma exposures, there were deaths from pancytopenia and thrombocytopenia, obviously related to radiation-induced bone-marrow damage. After that period, however, deaths were from common equine diseases; no death has resulted from a malignant neoplasm. Of the original 112 burros, 15 survive (10 irradiated and 5 controls). Survival curves determined for unirradiated and neutron-gamma- and gamma-irradiated burros showed significant differences. The mean survival times were: controls, 28 years; gamma irradiation only, 26 years; and neutron-gamma irradiation, 23 years. 3 refs., 4 figs., 1 tab

Irradiation effects in superconductor oxides. Effets d'irradiation dans les oxydes supraconducteurs

Energy Technology Data Exchange (ETDEWEB)

Rullier-Albenque, F; Konczykowski, M [CEA-Ecole Polytechnique, 91 - Palaiseau (France). Lab. d' Etudes des Solides Irradies

1993-01-01

Several effects of irradiation on the 92 K - oxide superconductor YBa[sub 2]Cu[sub 3]O[sub 7] are reported. Whatever irradiation type, the critical temperature T[sub c] is found to decrease and the resistivity to increase. At sufficiently high damage levels, YBa[sub 2]Cu[sub 3]O[sub 7] is no longer superconducting and even displays a semiconducting-like behaviour. The alterations of superconducting properties are clearly related to oxygen defects - in the CuO[sub 2] planes or CuO chains... but we have shown experimentally that copper defects are also important. Magnetic properties of YBa[sub 2]Cu[sub 3]O[sub 7] in mixed state are also very sensitive to irradiation. By pinning the flux lines, irradiation defects can considerably increase the critical current density j[sub c]. At present, irradiations by highly energetic heavy ions (6 GeV Pb for instance), which produce cylindrical tubes of amorphous material (latent tracks) throughout the whole thickness of the samples, are probably the most efficient way to enhance j[sub c]. (Author). 18 refs., 7 figs.

Food irradiation

International Nuclear Information System (INIS)

Beishon, J.

1991-01-01

Food irradiation has been the subject of concern and controversy for many years. The advantages of food irradiation include the reduction or elimination of dangerous bacterial organisms, the control of pests and insects which destroy certain foods, the extension of the shelf-life of many products, for example fruit, and its ability to treat products such as seafood which may be eaten raw. It can also replace existing methods of treatment which are believed to have hazardous side-effects. However, after examining the evidence produced by the proponents of food irradiation, the author questions whether it has any major contribution to make to the problems of foodborne diseases or world food shortages. More acceptable solutions, he suggests, may be found in educating food handlers to ensure that hygienic conditions prevail in the production, storage and serving of food. (author)

Development of an irradiation system for a small size continuous run multipurpose gamma irradiator

International Nuclear Information System (INIS)

Calvo, W.A.P.; Rela, P.R.; Napolitano, C.M.; Kodama, Y.; Omi, N.M.; Costa, F.E. da; Andradee Silva, L.G. de

2009-01-01

The Radiation Technology Center from IPEN-CNEN/SP, Brazil, developed a revolutionary design and national technology, a small-sized continuous run and multipurpose industrial gamma irradiator, to be used as a demonstration facility for manufacturers and contract service companies, which need economical and logistical in-house irradiation system alternatives. Also, to be useful for supporting the local scientific community on development of products and process using gamma radiation, assisting the traditional and potential users on process validation, training and qualification of operators and radioprotection officers. The developed technology for this facility consists of a continuous tote box transport system, comprising a single concrete vault, where the automated transport system of products inside and outside of the irradiator utilizes a rotating door, integrated with the shielding, avoiding the traditional maze configuration. Covering 76 m 2 of floor area, the irradiator design is a product overlap sources and the maximum capacity of cobalt-60 wet sources is 37 PBq. The performed qualification program of this multipurpose irradiator was based on AAMI/ISO 11137 standard, which recommends the inclusion of the following elements: installation and process qualification. The initial load of the multipurpose irradiator was 3.4 PBq with 13 cobalt-60 sources model C-188, supplied by MDS Nordion - Canada. For irradiator dose optimization, the source distribution was done using the software Cadgamma developed by IPEN-CNEN/SP. The polymethylmetacrylate (PMMA) dosimeter system, certified by the International Dose Assurance Service (IDAS) of the International Atomic Energy Agency (IAEA) was used for irradiator dose mapping. The economic analysis, performance concerning with dose uniformity and cobalt-60 utilization efficiency were calculated and compared with other commercial gamma irradiators available on the market. (authors)

Process for irradiation of polyethylene

International Nuclear Information System (INIS)

White, George.

1983-01-01

Irradiation of polyethylene affects its processabiltiy in the fabrication of products and affects the properties of products already fabricated. The present invention relates to a process for the irradiation of polyethylene, and especially to a process for the irradiation of homopolymers of ethylene and copolymers of ethylene and higher α-olefins, in the form of granules, with low levels of electron or gamma irradiation in the presence of an atomsphere of steam

Potato irradiation technology in Japan

International Nuclear Information System (INIS)

Takehisa, M.

1981-01-01

After the National research program on potato irradiation, the public consumption of potatoes irradiated to a maximum of 15 krad was authorized by the Ministry of Welfare. Shihoro Agricultural Cooperative Association, one of the largest potato producers in Japan with an annual production of 200,000 tons, intended an application of the irradiation to their potato storage system. This paper describes the technological background of the potato irradiation facility and operational experience. (author)

Electron beam irradiation facility for low to high dose irradiation applications

International Nuclear Information System (INIS)

Petwal, V.C.; Wanmode, Yashwant; Verma, Vijay Pal; Bhisikar, Abhay; Dwivedi, Jishnu; Shrivastava, P.; Gupta, P.D.

2013-01-01

Electron beam based irradiation facilities are becoming more and more popular over the conventional irradiator facilities due to many inherent advantages such as tunability of beam energy, availability of radiation both in electron mode and X-ray mode, wide range of the dose rate, control of radiation from a ON-OFF switch and other safety related merits. A prototype experimental facility based on electron accelerator has been set-up at RRCAT to meet the low-dose, medium dose and high-dose requirements for radiation processing of food, agricultural and medical products. The facility can be operated in the energy range from 7-10 MeV at variable power level from 0.05-3 kW to meet the dose rate requirement of 100 Gy to kGy. The facility is also equipped with a Bremsstrahlung converter optimized for X-ray irradiation at 7.5 MV. Availability of dose delivery in wide range with precision control and measurement has made the facility an excellent tool for researchers interested in electron/X-ray beam irradiation. A precision dosimetry lab based on alanine EPR and radiochromic film dosimetry system have been established to characterize the radiation field and precise dose measurements. Electron beam scattering technique has been developed to achieve low dose requirement for EB irradiation of various seeds such as groundnut, wheat, soybeans, moong beans, black gram etc. for mutation related studies. This paper describes various features of the facility together with the dosimetric measurements carried out for qualification of the facility and recent irradiation experiments carried out using this facility. (author)

Food irradiation now

International Nuclear Information System (INIS)

1982-01-01

From the start the Netherlands has made an important contribution to the irradiation of food through microbiological and toxicological research as well as through the setting-up of a pilot plant by the government and through the practical application of 'Gammaster' on a commercial basis. The proceedings of this tenth anniversary symposium of 'Gammaster' present all aspects of food irradiation and will undoubtedly help to remove the many misunderstandings. They offer information and indicate to the potential user a method that can make an important contribution to the prevention of decay and spoilage of foodstuffs and to the exclusion of food-borne infections and food poisoning in man. The book includes 8 contributions and 4 panel discussions in the field of microbiology; technology; legal aspects; and consumer aspects of food irradiation. As an appendix, the report 'Wholesomeness of irradiated food' of a joint FAO/IAEA/WHO Expert Committee has been added. (orig./G.J.P.)

Shipboard-irradiation of haddock

International Nuclear Information System (INIS)

Ehlermann, D.; Reinacher, E.; Antonacopoulos, N.

1977-01-01

Haddock caught during the 183rd and 185th voyage of the RV 'Anton Dohrn' off Faeroeer was gutted, washed and packed under vacuum in polyethylene pouches. The samples were irradiated with the onboard X-ray source. During one series of experiments a minimum dose of 65 krad and a maximum dose of 130 krad was used. During further series the minimal dose was set to 100 krad, resulting in maximum values of 140 krad and 180 krad. As judged by taste panel evaluation of steam-cooked, unseasoned filets, quality preservation of all samples during the first 16 days of iced storage did not depend on irradiation. After that period the fish had lost prime quality. At this time, irradiated samples were rated slightly better than unirradiated ones. Base on our results, the shipboard-irradiation of prepacked haddock cannot be recommended. This does not exclude that under different conditions (e.g. fishfilets in retail packages) beneficial effects of irradiation may be observed. (orig.) [de

Irradiation Creep in Graphite

Energy Technology Data Exchange (ETDEWEB)

Ubic, Rick; Butt, Darryl; Windes, William

2014-03-13

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

Shipboard-irradiation of haddock

International Nuclear Information System (INIS)

Ehlermann, D.; Reinacher, E.; Antonacopoulos, N.

1977-01-01

Haddock caught during the 183rd and 185th voyage of the RV 'Anton Dohrn' off Faeroer was gutted, washed and packed under vacuum in polythylene pouches. The samples were irradiated with the onboard X-ray source. During one series of experiments a minimum dose of 65 krad and a maximum dose of 130 krad was used. During further series the minimal dose was set to 100 krad, resulting in maximum values of 140 krad and 180 krad. As judged by taste panel evalution of steam-cooked, unseasoned filets, quality preservation of all samples during the first 16 days of iced storage did not depend on irradiation. After that period the fish had lost prime quality. At this time, irradiated samples were rated slightly better than unirradiated ones. On the basis of these results, the shipboard-irradiation of prepacked haddock cannot be recommended. This does not exclude that under different conditions (e.g. fishfilets in retail packages) beneficial effects of irradiation may be observed. (orig.) [de

Extracorporeal irradiation -Physicist perspective

International Nuclear Information System (INIS)

Vijayaprabhu, N.; Saravanan, K.S.; Gunaseelan; Vivekanandam, S.; Reddy, K.S.; Parthasarathy; Mourougan, S.; Elangovan, K.

2008-01-01

Extracorporeal irradiation (ECI) involves irradiation of body tissues, particularly malignant bones of the extremities, outside the body. This involves en bloc resection of the tumour, extracorporeal irradiation of the bone segment with a single dose of 50 Gy or more, and reimplantation of the irradiated bone with fixation devices. Bone tumours like Ewing's Sarcoma, Chondrosarcoma and Oesteosarcoma; in the involved sites like femur, tibia, humerus, ilium and sacrum can be treated with ECI. The reimplanted bone simply acts as a framework for appositional bone growth from surrounding healthy bones. The conventional indications for postoperative irradiation are still applied. The major advantages of ECI are the precise anatomic fit of the reimplanted bone segment, preservation of joint mobility and its potential in avoiding the growth discrepancy commonly seen in prosthetic replacement. The use of ECI was first described in 1968 and practiced in Australia since 1996. In our center, we have completed six ECIs

Crystalline plasticity constitutive equations for BCC steel at low temperature; Loi de comportement en plasticite cristalline pour acier a basse temperature

Energy Technology Data Exchange (ETDEWEB)

Monnet, G. [EDF RD, MMC, Avenue des Renardieres, Ecuelles, 77818 Moret-sur-Loing Cedex (France); Vincent, L. [CEA Saclay, DEN, SRMA, 91191 Gif-sur-Yvette Cedex (France)

2011-07-01

The prediction of the irradiation-induced evolution of the ductile-fragile transition curve of pressure vessel steels is a major research topic in the nuclear industry. Multi-scale approaches starting from ab initio scale up to macroscopic continuum mechanics are currently investigated through the European project PERFORM60. At the intermediate level of crystal plasticity, several effects need to be described accurately before considering the introduction of irradiation hardening mechanisms, such as the thermal activity of dislocations slip, the different mobilities between screw and edge dislocations at low temperature. These effects should be introduced in a crystal plasticity law used in finite-element simulations of polycrystalline aggregates. Accordingly, a new crystal plasticity law is proposed in this paper based on a critical analysis of previous numerical results obtained with a discrete dislocations dynamics code. (authors)

Development of blood irradiators

International Nuclear Information System (INIS)

Anon.

1981-01-01

This project is designed to improve the techniques of blood irradiation through the development of improved and portable blood irradiators. A portable blood irradiator, consisting of a vitreous carbon body and thulium-170 radiation source, was attached to dogs via a carotid-jugular shunt, and its effects on the immune system measured. The device has demonstrated both significant suppression of circulating lymphocytes and prolonged retention of skin allografts

Irradiation-enhanced and-induced mass transport

International Nuclear Information System (INIS)

Rehn, L.E.

1989-01-01

Irradiation can be used to enhance diffusion, that is, to increase the rate at which equilibrium is attained, as well as to induce nonequilibrium changes. The main factors influencing whether irradiation will drive a material toward or away from equilibrium are the initial specimen microstructure and geometry, irradiation temperature, and primary recoil spectrum. This paper summarizes known effects of irradiation temperature and primary recoil spectrum on mass transport during irradiation. In comparison to either electron or heavy-ion irradiation, it is concluded that relatively low-energy, light-ion bombardment at intermediate temperatures offers the greatest potential to enhance the rate at which equilibrium is attained. The greatest departures from equilibrium can be expected from irradiation with similar particles at very low temperatures

In situ transmission electron microscope studies of ion irradiation-induced and irradiation-enhanced phase changes

International Nuclear Information System (INIS)

Allen, C.W.

1992-01-01

Motivated at least initially by materials needs for nuclear reactor development, extensive irradiation effects studies employing transmission electron microscopes (TEM) have been performed for several decades, involving irradiation-induced and irradiation-enhanced microstructural changes, including phase transformations such as precipitation, dissolution, crystallization, amorphization, and order-disorder phenomena. From the introduction of commercial high voltage electron microscopes (HVEM) in the mid-1960s, studies of electron irradiation effects have constituted a major aspect of HVEM application in materials science. For irradiation effects studies two additional developments have had particularly significant impact; the development of TEM specimen holder sin which specimen temperature can be controlled in the range 10-2200 K and the interfacing of ion accelerators which allows in situ TEM studies of irradiation effects and the ion beam modification of materials within this broad temperature range. This paper treats several aspects of in situ studies of electron and ion beam-induced and enhanced phase changes and presents two case studies involving in situ experiments performed in an HVEM to illustrate the strategies of such an approach of the materials research of irradiation effects

Sewage sludge irradiation with electrons

International Nuclear Information System (INIS)

Tauber, M.

1976-01-01

The disinfection of sewage sludge by irradiation has been discussed very intensively in the last few months. Powerful electron accelerators are now available and the main features of the irradiation of sewage sludge with fast electrons are discussed and the design parameters of such installations described. AEG-Telefunken is building an irradiation plant with a 1.5 MeV, 25 mA electron accelerator, to study the main features of electron irradiation of sewage sludge. (author)

Independent Laboratory for Detection of Irradiated Foods. Detection of the irradiated food in the INCT

International Nuclear Information System (INIS)

Stachowicz, W.

2007-01-01

Lecture shows different methods applied for detection of irradiated foods. Structure and equipment of the Independent Laboratory for Detection of Irradiated Foods operating in the INCT is described. Several examples of detection of food irradiation are given in details

Market testing of irradiated food

International Nuclear Information System (INIS)

Duc, Ho Minh

2001-01-01

Viet Nam has emerged as one of the three top producers and exporters of rice in the world. Tropical climate and poor infrastructure of preservation and storage lead to huge losses of food grains, onions, dried fish and fishery products. Based on demonstration irradiation facility pilot scale studies and marketing of irradiated rice, onions, mushrooms and litchi were successfully undertaken in Viet Nam during 1992-1998. Irradiation technology is being used commercially in Viet Nam since 1991 for insect control of imported tobacco and mould control of national traditional medicinal herbs by both government and private sectors. About 30 tons of tobacco and 25 tons of herbs are irradiated annually. Hanoi Irradiation Centre has been continuing open house practices for visitors from school, universities and various different organizations and thus contributed in improved public education. Consumers were found to prefer irradiated rice, onions, litchi and mushrooms over those nonirradiated. (author)

High-dose irradiation of food

International Nuclear Information System (INIS)

Diehl, J.F.

1999-01-01

Studies performed on behalf of the International Project on Food Irradiation in the period from 1971 until 1980 resulted in the concluding statement that ''.the irradiation of any food commodity up to an overall average dose of 10 kGy presents no toxicological hazard; hence, toxicological testing of foods so treated is no longer required.'' Since then, licenses for food irradiation have been restricted to this maximum dose in any country applying this technology. Further testing programmes have been carried out investigating the wholesomeness or hazards of high-dose irradiation, but there has been little demand so far by the food industry for licensing of high-dose irradiation, as there is only a small range of products whose irradiation at higher doses offers advantages for given, intended use. These include eg. spices, dried herbs, meat products in flexible pouch packagings for astronauts, or patients with immune deficiencies. (orig./CB) [de

Irradiation creep models - an overview

International Nuclear Information System (INIS)

Matthews, J.R.; Finnis, M.W.

1988-01-01

The modelling of irradiation creep is now highly developed but many of the basic processes underlying the models are poorly understood. A brief introduction is given to the theory of cascade interactions, point defect clustering and dislocation climb. The range of simple irradiation creep models is reviewed including: preferred nucleation of interstitial loops; preferred absorption of point defects by dislocations favourably orientated to an applied stress; various climb-enhanced glide and recovery mechanisms, and creep driven by internal stresses produced by irradiation growth. A range of special topics is discussed including: cascade effects; creep transients; structural and induced anisotropy; and the effect of impurities. The interplay between swelling and growth with thermal and irradiation creep is emphasized. A discussion is given on how irradiation creep theory should best be developed to assist the interpretation of irradiation creep observations and the requirements of reactor designers. (orig.)

Irradiated ready-to-eat spinach leaves: How information influences awareness towards irradiation treatment and consumer's purchase intention

Science.gov (United States)

Finten, G.; Garrido, J. I.; Agüero, M. V.; Jagus, R. J.

2017-01-01

This article aims to clarify and supply further information on food irradiation acceptance, with particular focus on Argentina and irradiated ready-to-eat (RTE) spinach leaves through an open web-online survey. Results showed that half of respondents did not know food irradiation, but the other half demonstrated uncertainty despite they declared they had knowledge about it; thus, confirming little awareness towards this technology. Respondents who believed in the misleading myth about food irradiation represented 39%, while roughly the same number was doubtful. On the other hand, after supplying informative material, respondents were positively influenced and an increase in acceptance by 90% was found. Finally, 42% of respondents were willing to consume/purchase irradiated RTE spinach leaves, and 35% remained doubtful. Respondents who did not exclude to accept irradiated spinach could be considered potential consumers if intensive campaigns about the benefits of food irradiation were carried out by reliable actors. If the Argentinean RTE market grew, following the world consumption trend towards these products, irradiated spinach leaves could be successfully introduced by making better efforts to inform consumers about food irradiation.

Irradiation sequels of retinoblastomas

International Nuclear Information System (INIS)

Benk, V.; Habrand, J.L.; Bloch Michel, E.; Soussaline, M.; Sarrazin, D.

1993-01-01

From 1975 to 1985, 34 children with a non-metastatic retinoblastoma were irradiated at the Institut Gustave-Roussy. After enucleation, 19 bilateral tumors were irradiated by two lateral opposed fields and 15 unilateral tumors by one lateral and anterior field, in the case of optic nerve being histologically positive. Dose was 45 Gy, 1.8 Gy per fraction. The 10-year-survival rate for unilateral and bilateral retinoblastomas was 79%. Long term sequels were available for 25 patients: 88% retained one functional eye. Three children with bilateral retinoblastomas developed a cataract in the residual eye between 2 and 5 years after irradiation, none with unilateral tumor. Nine patients (36%), seven with unilateral and two with bilateral tumor developed a cosmetical problem that required multiple surgical rehabilitation between 3 and 14 years after irradiation. Nine children (36%), five with unilateral and four with bilateral tumors developed growth hormone deficit between 2 and 8 years after irradiation that required hormone replacement. Their pituitary gland received 22 to 40 Gy. No osteosarcoma occurred in this population. Among long-term sequels, following irradiation for retinoblastoma, cosmetical deformities represent disabling sequels that could justify new approaches in radiotherapy, as protontherapy combined with 3-D-treatment planning

Comportement des poteaux composites en profils creux en acier remplis de béton Behavior of composite columns in hollow steel section filled with concrete

Directory of Open Access Journals (Sweden)

Othmani N.

2012-09-01

Full Text Available Le but de cet article, est la determination des rigidites flexionnelles EIx et EIy d’fune section mixte acier beton et plus precisement d’fun poteau en tube d’facier de section rectangulaire, remplie de beton, sollicitee a la flexion bi-axiale (N, Mx et My. L’festimation des rigidites sera faite a partir d’fune approche theorique par une analyse du poteau en elements finis (element barre a 4 degres de liberte, basee sur les conditions d’fequilibres a mi-portee en utilisant la relation moment-courbure (M–Φ de l’felement deforme par application de l’fequation suivante: EI=M/Φ. Le comportement des materiaux est celui comme adopte par les reglements Eurocode 2 et 3, respectivement pour le beton et l’facier. Afin de valider l’fapproche theorique utilisee dans cette etude, deux comparaisons ont ete faites : une premiere permettant de comparer les resultats des rigidites determinees par les relations moments courbures et celles calculees par l’fEurocode 4 et une deuxieme comparaison entre les charges de ruines de deux poteaux de grandeurs natures avec ceux testes au laboratoire [2]. Au vu des resultats obtenus, nous pouvons conclure que l’approche théorique utilisée dans cette étude ainsi que les modèles de comportement des matériaux sont adéquats pour ce genre de problèmes. The purpose of this paper is the determination of flexural stiffness EIx and EIy of a concrete filled rectangular cross section of a composite steel column, under biaxial bending (N, Mx and My. The rigidities will be estimated from a theoretical approach using a finite element analysis (element bar with 4 degrees of freedom, based on the equilibrium conditions at mid-span using the moment-curvature relationships (M–Φ of the deformed element by applying the following equation: EI=M/Φ. The material behavior is the one adopted by Eurocode 2 and 3, respectively, for concrete and steel. To validate the theoretical approach used, two comparisons

Assessing Nutrients Availability of Irradiated and Non-Irradiated Biosolids for the Agriculture Re-use

Energy Technology Data Exchange (ETDEWEB)

Magnavacca, Cecilia; Sanchez, Monica

2003-07-01

Irradiation provides a fast and reliable means to disinfect biosolids generated by municipal wastewater treatment processes. The chemical integrity of some substances may be altered thus change the availability of plant nutrients. Chemical analyses on the biosolids showed a release of mineral forms of Nitrogen while Phosphorus chemical forms were not altered. Higher amounts of mineralized N were indirectly demonstrated in soils with irradiated biosolids by a respiration experiment, and higher nitrate concentrations were measured in the irradiated biosolids amended soils at field experiments. Crop field experiments (lettuce and sugarcane) confirmed that irradiated biosolids have higher fertilizing capability than equal amounts of non-irradiated biosolids. Maximum dose rate had no additive effect but a depleted result, thus marking the importance of the use of moderate biosolids rates. (author)

Safer food means food irradiation

International Nuclear Information System (INIS)

Steele, J.H.

2000-01-01

In this article the author presents the sanitary advantages that are brought by food irradiation. OMS experts state that this technique is safe and harmless for any average global dose between 10 KGy and 100 KGy. Whenever a seminar is held on the topic, it is always concluded that food irradiation should be promoted and favoured. In France food irradiation is authorized for some kinds of products and exceptionally above a 10 KGy dose. Historically food irradiation has been hampered in its development by its classification by American Authorities as food additives in 1958 (Delanay clause). The author draws a parallel between food irradiation and pasteurization or food deep-freezing in their beginnings. (A.C.)

Food irradiation: the 'experts' choice

International Nuclear Information System (INIS)

Watts, P.

1990-01-01

The UK Government has decided to lift the ban on food irradiation. The proponents of food irradiation claim it is an effective and safe means of preserving food, at minimum risk to the public. However, the prospect of irradiated food being on the shelves has created considerable opposition from environmental, consumer, public health groups and trade unions. The long list of unanswered health and safety questions means the public could be exposed to a whole new range of risks. The consumer is justified as saying ''if food has to be irradiated, what was wrong with it, good food does not need irradiating''. The answer to food contamination is improved hygiene and training in farm, factory and shop. (author)

The return of food irradiation

International Nuclear Information System (INIS)

Hammerton, K.

1992-01-01

In discussing the need for food irradiation the author examines the problems that arise in processing foods of different kinds: spices, meat, fruits and vegetables. It is demonstrated that the relatively low dose of radiation required to eliminate the reproductive capacity of the pest can be tolerated by most fruits and vegetables without damage. Moreover the safety of irradiated food is acknowledged by major national and international food organizations and committees. The author agreed that when food irradiation has been approved by a country, consumers should be able to choose between irradiated and non-irradiated food. To enable the choice, clear and unambiguous labelling must be enforced. 13 refs., 1 tab., ills

X-ray irradiation of RC-MAP pre-stored for various numbers of days. Effect of X-ray irradiation on RC-MAP and reuse of RC-MAP after irradiation

International Nuclear Information System (INIS)

Yamada, Naotomo; Nagumo, Fumio; Kawasaki, Seiji; Matsuzaki, Miwako; Tadano, Jutaro

1995-01-01

X-ray irradiation is currently in wide use as a means of preventing post-transfusion graft-versus-host disease (PT-GVHD). In this study, we evaluated the effects of X-ray irradiation on RC-MAP pre-stored for various numbers of days, and assessed how long irradiated RC-MAP can be stored. RC-MAP was irradiated at a dosage of 15 Gy at 1, 7, 14, 21 or 28 days after blood collection. These specimens were referred to as group I, II, III, IV and V (X-ray-irradiated groups), respectively. Non-irradiated RC-MAP was used as the control. Results showed that plasma K concentration increased after X-ray irradiation. It is therefore advisable that RC-MAPs be used immediately in infants and in renal failure. However, to maximize the efficiency of blood product use, it seemed possible that groups I and II could be used within two weeks after irradiation, and group III within one week. On the basis of this increase in K concentration, however, groups IV and V plasma should be used immediately after irradiation. (author)

Sensorial evaluation of irradiated mangoes

International Nuclear Information System (INIS)

Broisler, Paula Olhe; Cruz, Juliana Nunes da; Sabato, Susy Frey

2007-01-01

Mango (Mangifera indica L.) is a tropical fruit of great economical relevance in the world, mainly for tropical countries like Brazil. It consists in the second tropical fruit more important grown in the world. On the other hand it is a very perishable fruit and its delivery to distant points is restricted due to short shelf life at environmental temperature. Food irradiation process is applied to fruits for their preservation, once it promotes disinfestation and even maturation retard, among other mechanisms. The Brazilian legislation permits the food irradiation and does not restrict the doses to be delivered. In order to verify eventual changes, sensorial evaluation is very important to study how irradiation affects the quality of the fruit and its acceptability. Mangoes were irradiated in a Cobalto-60 source, from the Radiation Technology Center, CTR, of IPEN/CNEN-SP at doses 0,5 kGy e 0,75 kGy. The sensorial evaluation was measured through Acceptance Test where irradiated samples were offered together with control sample to the tasters who answered their perception through hedonic scale. The parameters Color, Odor, Flavor and Texture were analyzed. Statistical analysis showed that only Odor parameter was different from control (sample irradiated at 0.5 kGy). Few tasters indicated that irradiated mangoes had fewer odors in relation to non-irradiated samples. (author)

Sensorial evaluation of irradiated mangoes

Energy Technology Data Exchange (ETDEWEB)

Broisler, Paula Olhe; Cruz, Juliana Nunes da; Sabato, Susy Frey [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)]. E-mails: paulabroisler@hotmail.com; juliananc@ig.com.br; sfsabato@ipen.br

2007-07-01

Mango (Mangifera indica L.) is a tropical fruit of great economical relevance in the world, mainly for tropical countries like Brazil. It consists in the second tropical fruit more important grown in the world. On the other hand it is a very perishable fruit and its delivery to distant points is restricted due to short shelf life at environmental temperature. Food irradiation process is applied to fruits for their preservation, once it promotes disinfestation and even maturation retard, among other mechanisms. The Brazilian legislation permits the food irradiation and does not restrict the doses to be delivered. In order to verify eventual changes, sensorial evaluation is very important to study how irradiation affects the quality of the fruit and its acceptability. Mangoes were irradiated in a Cobalto-60 source, from the Radiation Technology Center, CTR, of IPEN/CNEN-SP at doses 0,5 kGy e 0,75 kGy. The sensorial evaluation was measured through Acceptance Test where irradiated samples were offered together with control sample to the tasters who answered their perception through hedonic scale. The parameters Color, Odor, Flavor and Texture were analyzed. Statistical analysis showed that only Odor parameter was different from control (sample irradiated at 0.5 kGy). Few tasters indicated that irradiated mangoes had fewer odors in relation to non-irradiated samples. (author)

Irradiation and pregnancy

Energy Technology Data Exchange (ETDEWEB)

Chouraqui, A; Creuzillet, C; Barrat, J [Hopital Saint-Antoine, 75 - Paris (France)

1985-04-21

Every single person is exposed to natural (7 rads) or artificail (7.25 rads) irradiation throughout life. To which must be added, for many, irradiation from radiological examinations, which may cause malformations, genetic defects or cancer. The management of irradiated pregnant women depends on the dose received and on the age of pregnancy and requires, when the patient is seen, close co-operation between genetician, radiologist and gynaecologist. A radiological examination may be irreplaceable for diagnostic purposes, but the benefits to be expected from it should not lead to problems, particularly human problems, that are extremely difficult to solve. Non-urgent X-ray examinations should be performed outside pregnancy.

Facts about food irradiation. A series of fact sheets from the International Consultative Group on Food Irradiation

Energy Technology Data Exchange (ETDEWEB)

NONE

1991-12-01

The safety and benefits of foods processed by ionizing radiation are well documented. In an effort to provide governments, especially those of developing countries, with scientifically accurate information on issues of general interest to the public, the International Consultative Group on Food Irradiation (ICGFI), which was established under the aegis of the Food and Agriculture Organization of the United Nations (FAO), the World Health Organization (WHO), and the IAEA, decided at its 7th Annual Meeting in Rome, Italy, on October 1990, to issue a series of ''Fact Sheets'' on the subject. ICGFI, an inter-governmental body with a membership of 37 governments, has as one of its mandates the function to provide information to Member States of the FAO, WHO, and IAEA and to the three organizations themselves on the safe and proper use of food irradiation technology. The Fact Sheets included here cover issues relating to: status and trends; scientific and technical terms; food irradiation and radioactivity; chemical changes in irradiated food; nutritional quality of irradiated foods; genetic studies; microbiological safety of irradiated food; irradiation and food safety; irradiation and food additives and residues; packaging of irradiated foods; safety of irradiation facilities; controlling the process; food irradiation costs; and irradiated foods and the consumer. The Fact Sheets have been separately indexed and included in the INIS Database under Reference Numbers 23011206-23011217, 23011319 and 23012743. The Fact Sheets were first issued by the ICGFI Secretariat (Joint FAO/IAEA Division of Nuclear Techniques in Food and Agriculture, Vienna, Austria) in May 1991.

Facts about food irradiation. A series of fact sheets from the International Consultative Group on Food Irradiation

International Nuclear Information System (INIS)

1991-12-01

The safety and benefits of foods processed by ionizing radiation are well documented. In an effort to provide governments, especially those of developing countries, with scientifically accurate information on issues of general interest to the public, the International Consultative Group on Food Irradiation (ICGFI), which was established under the aegis of the Food and Agriculture Organization of the United Nations (FAO), the World Health Organization (WHO), and the IAEA, decided at its 7th Annual Meeting in Rome, Italy, on October 1990, to issue a series of ''Fact Sheets'' on the subject. ICGFI, an inter-governmental body with a membership of 37 governments, has as one of its mandates the function to provide information to Member States of the FAO, WHO, and IAEA and to the three organizations themselves on the safe and proper use of food irradiation technology. The Fact Sheets included here cover issues relating to: status and trends; scientific and technical terms; food irradiation and radioactivity; chemical changes in irradiated food; nutritional quality of irradiated foods; genetic studies; microbiological safety of irradiated food; irradiation and food safety; irradiation and food additives and residues; packaging of irradiated foods; safety of irradiation facilities; controlling the process; food irradiation costs; and irradiated foods and the consumer. The Fact Sheets have been separately indexed and included in the INIS Database under Reference Numbers 23011206-23011217, 23011319 and 23012743. The Fact Sheets were first issued by the ICGFI Secretariat (Joint FAO/IAEA Division of Nuclear Techniques in Food and Agriculture, Vienna, Austria) in May 1991

Development of an irradiation system for a small size continuous run multipurpose gamma irradiator

International Nuclear Information System (INIS)

Calvo, Wilson Aparecido Parejo

2005-01-01

The Radiation Technology Center from Instituto de Pesquisas Energeticas e Nucleares (IPEN-CNEN/SP), Brazil, developed with a revolutionary design and national technology, a small size continuous run and multipurpose industrial gamma irradiator, to be used as a demonstration facility for manufacturers and contract service companies, which need economical and logistical in-house irradiation system alternatives. Also, to be useful for supporting the local scientific community on development of products and process using gamma radiation, assisting the traditional and potential users on process validation, training and qualification of operators and radioprotection officers. The developed technology for this facility consists of continuous tote box transport system, comprising a single concrete vault, where the automated transport system of products inside and outside of the irradiator utilizes a rotate door, integrated with the shielding, avoiding the traditional maze configuration. Covering 76 m 2 of floor area, the irradiator design is product overlap sources and the maximum capacity of cobalt-60 wet sources is 37 P Bq (1 MCi). The performed quantification program of this multipurpose irradiator was based on AAMI/ISO 11137 standard, which recommends the inclusion of the following elements: installation and process quantification. The initial load of the multipurpose irradiator was 3.4 P Bq (92.1 k Ci) with 13 cobalt-60 sources model C-188, supplied by MDS Nordion Ion Technologies - Canada. For irradiator dose optimization, the source distribution was done using the software Cadgamma developed by IPEN-CNEN/SP. The poly-methylmethacrylate (PMMA) dosimeters system, certified by the International Dose Assurance Service (IDAS) of the International Atomic Energy Agency (IAEA) was used for irradiator dose mapping. The economic analysis, performance concerning to dose uniformity and cobalt-60 utilization efficiency were calculated and compared with other commercial gamma

Positive ion irradiation facility

International Nuclear Information System (INIS)

Braby, L.A.

1985-01-01

Many questions about the mechanisms of the response of cells to ionizing radiation can best be investigated using monoenergetic heavy charged particle beams. Questions of the role of different types of damage in the LET effect, for example, are being answered by comparing repair kinetics for damage induced by electrons with that produced by helium ions. However, as the models become more sophicated, the differences between models can be detected only with more precise measurements, or by combining high- and low-LET irradiations in split-dose experiments. The design of the authors present cell irradiation beam line has limited the authors to irradiating cells in a partial vacuum. A new way to mount the dishes and bring the beam to the cells was required. Several means of irradiating cells in mylar-bottom dishes have been used at other laboratories. For example at the RARAF Facility, the dual ion experiments are done with the dish bottom serving as the beam exit window but the cells are in a partial vacuum to prevent breaking the window. These researchers have chosen instead to use the dish bottom as the beam window and to irradiate the entire dish in a single exposure. A special, very fast pumping system will be installed at the end of the beam line. This system will make it possible to irradiate cells within two minutes of installing them in the irradiation chamber. In this way, the interaction of electron and ion-induced damage in Chlamydomonas can be studied with time between doses as short as 5 minutes

Vinca irradiator

International Nuclear Information System (INIS)

Eymery, R.

1976-10-01

The development programme of the VINCA radiosterilisation centre involves plans for an irradiator capable of working in several ways. Discontinuous operation. The irradiator is loaded for a certain period then runs automatically until the moment of unloading. This method is suitable as long as the treatment capacity is relatively small. Continuous operation with permanent batch loading and unloading carried out either manually or automatically (by means of equipment to be installed later). Otherwise the design of the apparatus is highly conventional. The source is a vertical panel submersible in a pool. The conveyor is of the 'bucket' type, with 4 tiers to each bucket. The batches pass successively through all possible irradiation positions. Transfert into and out of the cell take place through a maze, which also provides access to the cell when the sources are in storage at the bottom of the pool [fr

Irradiation preservation of Korean shellfish

International Nuclear Information System (INIS)

Chung, J.R.; Kim, S.I.; Lee, M.C.

1976-01-01

Pacific oyster, hard clam and mussel were irradiated at doses up to 0.5 Mrad, the optimum dose rather than the maximum permissible was sought for in each species and post-irradiation storage characteristics studied at 0 0 and 5 0 C. No shellfish meat irradiated at doses as high as 0.5 Mrad produced any adverse odor. However the organoleptic quality of each sample irradiated at lower doses was superior to those irradiated at the higher during the early storage period. The optimum dose was determined to be 0.2 Mrad for Pacific oyster and mussel and 0.1 Mrad for hard clam. By irradiating at the optimum dose, the storage life of Pacific oyster could be extended from less than 14 days to 35 days at 0 0 C and from only 3 days to 21 days at 5 0 C. A similar storage extension was observed from 7 days to 14 days at 0 0 C and from 3 days to 12 days at 5 0 C. The hard clam meats were particularly susceptible to tissue softening by irradiation; an earlier onset and more extensive softening were observed with increasing dose. (author)

Detection of some irradiated foods

International Nuclear Information System (INIS)

NASR, E.H.A

2009-01-01

This study was performed to investigate the possibility of using two rapid methods namely Supercritical Fluid Extraction (SFE) and Direct Solvent Extraction (DSE) methods for extraction and isolation of 2-dodecylcyclobutanone (2-DCB) followed by detecting this chemical marker by Gas chromatography technique and used this marker for identification of irradiated some foods containing fat (beef meat, chicken, camembert cheese and avocado) post irradiation, during cold and frozen storage. Consequently, this investigation was designed to study the following main points:- 1- The possibility of applying SFE-GC and DSE-GC rapid methods for the detection of 2-DCB from irradiated food containing fat (beef meat, chicken, camembert cheese and avocado fruits) under investigation.2-Studies the effect of gamma irradiation doses on the concentration of 2-DCB chemical marker post irradiation and during frozen storage at -18 degree C of chicken and beef meats for 12 months.3-Studies the effect of gamma irradiation doses on the concentration of 2-DCB chemical marker post irradiation and during cold storage at 4±1 degree C of camembert cheese and avocado fruits for 20 days.

How to improve the irradiation conditions for the International Fusion Materials Irradiation Facility

CERN Document Server

Daum, E

2000-01-01

The accelerator-based intense D-Li neutron source International Fusion Materials Irradiation Facility (IFMIF) provides very suitable irradiation conditions for fusion materials development with the attractive option of accelerated irradiations. Investigations show that a neutron moderator made of tungsten and placed in the IFMIF test cell can further improve the irradiation conditions. The moderator softens the IFMIF neutron spectrum by enhancing the fraction of low energy neutrons. For displacement damage, the ratio of point defects to cascades is more DEMO relevant and for tritium production in Li-based breeding ceramic materials it leads to a preferred production via the sup 6 Li(n,t) sup 4 He channel as it occurs in a DEMO breeding blanket.

Wholesomeness and safety of irradiated foods

International Nuclear Information System (INIS)

Swallow, A.J.

1991-01-01

Irradiation with gamma-rays, X-rays or fast electrons can be used to change foodstuffs in beneficial ways or to destroy harmful organisms. Gamma rays do not induce radioactivity in foods, but X-rays and fast electrons can induce short lived radioactivity if sufficiently energetic. This imposes limitations on the energies which can be used, and a short wait between irradiation and consumption may be advisable. Irradiation produces chemical changes in foodstuffs, and some foods are unsuitable for irradiation. With appropriate foods, trials with animals and human volunteers generally show that the product is safe. Some loss in nutritional quality can take place, which could be significant for some individuals, but are unlikely to be important for those on a balanced diet. Irradiation does not eliminate all risk from microbial contamination. Foods to be irradiated should be good quality, and need to be kept under proper conditions after irradiation. Irradiated foods should be appropriately labelled. Tests for radiation would help to enforce necessary controls. If the process is properly carried out on appropriate foods, and all due precautions are taken, irradiated foods are wholesome and safe. 52 references

Electron irradiation of dry food products

Energy Technology Data Exchange (ETDEWEB)

Gruenewald, Th [Bundesbahn-Zentralamt, Minden (Germany, F.R.)

1983-01-01

The interest of the industrial food producer is increasing in having the irradiation facility installed in the food processing chain. The throughput of the irradiator should be high and the residence time of the product in the facility should be short. These conditions can be accomplished by electron irradiators. To clarify the irradiation conditions spices taken out of the industrial process, food grade salt, sugar, and gums as models of dry food products were irradiated. With a radiation dose of 10 kGy microbial load can be reduced on 10**4 microorganisms/g. The sensory properties of the spices were not changed in an atypical way. For food grade salt and sugar changes of colour were observed which are due to lattice defects or initiated browning. The irradiation of several gums led only in some cases to an improvement of the thickness properties in the application below 50 deg C, in most cases the thickness effect was reduced. The products were packaged before irradiation. But it would be possible also to irradiate the products without packaging moving the product through the irradiation field in a closed conveyor system.

Electron irradiation of dry food products

International Nuclear Information System (INIS)

Gruenewald, Th.

1983-01-01

The interest of the industrial food producer is increasing in having the irradiation facility installed in the food processing chain. The throughput of the irradiator should be high and the residence time of the product in the facility should be short. These conditions can be accomplished by electron irradiators. To clarify the irradiation conditions spices taken out of the industrial process, food grade salt, sugar, and gums as models of dry food products were irradiated. With a radiation dose of 10 kGy microbial load can be reduced on 10**4 microorganisms/g. The sensory properties of the spices were not changed in an atypical way. For food grade salt and sugar changes of colour were observed which are due to lattice defects or initiated browning. The irradiation of several gums led only in some cases to an improvement of the thickness properties in the application below 50 deg C, in most cases the thickness effect was reduced. The products were packaged before irradiation. But it would be possible also to irradiate the products without packaging moving the product through the irradiation field in a closed conveyor system. (author)

Detection of hydrocarbons in irradiated foods

International Nuclear Information System (INIS)

Miyahara, Makoto; Maitani, Tamio; Saito, Akiko; Kamimura, Tomomi; Nagasawa, Taeko; Kobayashi, Yasuo; Ito, Hitoshi

2003-01-01

The hydrocarbon method for the detection of irradiated foods is now recognized as the international technique. This method is based on radiolysis of fatty acids in food to give hydrocarbons. In order to expand this technique's application, ten foods (butter, cheese, chicken, pork, beef, tuna, dry shrimp, avocado, papaya, and mango) were irradiated in the range from 0.5 to 10 kGy and the hydrocarbons in them were detected. Recoveries of the hydrocarbons from most foods were acceptable (38-128%). Some hydrocarbons were found in non-irradiated foods, particularly, in butter, cheese, tuna, and shrimp. Seven irradiated foods, butter, cheese, chicken, beef, pork, tuna, dry shrimp, and avocado were detectable at their practical doses by measuring the appropriate marker hydrocarbons. In most case, marker hydrocarbon will be 1,7-hexadecadiene. However, the marker hydrocarbons produced only in irradiated foods varied from food to food; therefore, it is necessary to check a specific irradiated food for marker hydrocarbons. On the other hand, two irradiated foods (papaya and mango which were irradiated at their practical doses) were difficult to distinguish from non-irradiated foods using this method. (author)

Detection of hydrocarbons in irradiated foods

Energy Technology Data Exchange (ETDEWEB)

Miyahara, Makoto; Maitani, Tamio [National Inst. of Health Sciences, Tokyo (Japan); Saito, Akiko; Kamimura, Tomomi; Nagasawa, Taeko [Kitasato Univ., Sagamihara, Kanagawa (Japan). School of Allied Health Sciences; Kobayashi, Yasuo; Ito, Hitoshi [Japan Atomic Energy Research Inst., Takasaki, Gunma (Japan). Takasaki Radiation Establishment

2003-06-01

The hydrocarbon method for the detection of irradiated foods is now recognized as the international technique. This method is based on radiolysis of fatty acids in food to give hydrocarbons. In order to expand this technique's application, ten foods (butter, cheese, chicken, pork, beef, tuna, dry shrimp, avocado, papaya, and mango) were irradiated in the range from 0.5 to 10 kGy and the hydrocarbons in them were detected. Recoveries of the hydrocarbons from most foods were acceptable (38-128%). Some hydrocarbons were found in non-irradiated foods, particularly, in butter, cheese, tuna, and shrimp. Seven irradiated foods, butter, cheese, chicken, beef, pork, tuna, dry shrimp, and avocado were detectable at their practical doses by measuring the appropriate marker hydrocarbons. In most case, marker hydrocarbon will be 1,7-hexadecadiene. However, the marker hydrocarbons produced only in irradiated foods varied from food to food; therefore, it is necessary to check a specific irradiated food for marker hydrocarbons. On the other hand, two irradiated foods (papaya and mango which were irradiated at their practical doses) were difficult to distinguish from non-irradiated foods using this method. (author)

Changes of lipids in irradiated chickens

International Nuclear Information System (INIS)

Moersel, J.T.; Wende, I.; Schwarz, K.

1991-01-01

Chickens were irradiated in a 6 deg Co gamma irradiation source. The irradiation has been done to reduce or eliminate Salmonella. The experiments were done to test this decontamination method of chickens if changes of lipids take place. It was to be seen, that peroxidation of lipids was more rapidly as in control. The time of storage of irradiated chickens has to be shorter because of changes in lipids. After irradiation the chickens had trade quality. (orig.) [de

Dose rate distribution for products irradiated in a semi-industrial irradiation plant. 1st stage

International Nuclear Information System (INIS)

Mangussi, J.

2005-01-01

The model of the bulk product absorbed dose rate distribution in a semi industrial irradiation plant is presented. In this plant the products are subject to a dynamic irradiation process: single-plaque, single-direction, four-passes. The additional two passes, also one on each side of the plaque, serve to minimize the lateral dose variation as well as the depth-dose non-uniformity. The first stage of this model takes only into account the direct absorbed dose rate; the model outputs are the depth-dose distribution and the lateral-dose distribution. The calculated absorbed dose in the bulk product and its uniformity-ratio after the dynamic irradiation process for different products is compared. The model results are in good agreement with the experimental measurements in a bulk of irradiated product; and the air absorbed dose rate in the irradiation chamber behind the product subject to the dynamic irradiation process. (author) [es

Flux effect on neutron irradiation embrittlement of reactor pressure vessel steels irradiated to high fluences

International Nuclear Information System (INIS)

Soneda, N.; Dohi, K.; Nishida, K.; Nomoto, A.; Iwasaki, M.; Tsuno, S.; Akiyama, T.; Watanabe, S.; Ohta, T.

2011-01-01

Neutron irradiation embrittlement of reactor pressure vessel (RPV) steels is of great concern for the long term operation of light water reactors. In particular, the embrittlement of the RPV steels of pressurized water reactors (PWRs) at very high fluences beyond 6*10 19 n/cm 2 , E > 1 MeV, needs to be understood in more depth because materials irradiated in material test reactors (MTRs) to such high fluences show larger shifts than predicted by current embrittlement correlation equations available worldwide. The primary difference between the irradiation conditions of MTRs and surveillance capsules is the neutron flux. The neutron flux of MTR is typically more than one order of magnitude higher than that of surveillance capsule, but it is not necessarily clear if this difference in neutron flux causes difference in mechanical properties of RPV. In this paper, we perform direct comparison, in terms of mechanical property and microstructure, between the materials irradiated in surveillance capsules and MTRs to clarify the effect of flux at very high fluences and fluxes. We irradiate the archive materials of some of the commercial reactors in Japan in the MTR, LVR-15, of NRI Rez, Czech Republic. Charpy impact test results of the MTR-irradiated materials are compared with the data from surveillance tests. The comparison of the results of microstructural analyses by means of atom probe tomography is also described to demonstrate the similarity / differences in surveillance and MTR-irradiated materials in terms of solute atom behavior. It appears that high Cu material irradiated in a MTR presents larger shifts than those of surveillance data, while low Cu materials present similar embrittlement. The microstructural changes caused by MTR irradiation and surveillance irradiation are clearly different

Significance of postoperative irradiation for breast cancer

International Nuclear Information System (INIS)

Murai, Nobuko; Ogami, Koji; Nishikawa, Kiyoshi; Koga, Kenji; Waki, Norio; Higashi, Hidefumi; Hayashi, Asami; Shibata, Koichiro; Watanabe, Katsuji

1986-01-01

From 1978 through 1983, 27 patients were treated with surgery followed by irradiation (irradiated group) and 29 with surery alone (non-irradiated group). In the irradiated group, 10 had stage II and 17 stage III; in the non-irradiated group, 25 had stage II and 4 stage III. The most common histology was medullary tubular carcinoma (MTC). There was no significant difference in survivals at 3 years and 5 years between the groups. Similarly, no significant difference was seen among stage II patients. Patients with MTC tended to have worse survivals in the irradiated group than in the non-irradiated group, with no statistically significant difference. Among stage II patients, no major differences in local recurrence were seen between the groups; the incidence of distant metastases tended to be high in the irradiated group. The incidence of both local recurrence and distant metastases for stage III patients showed a tendency to be higher in the irradiated group than in the non-irradiated group. The results indicated no apparent benifit of postoperative irradiation for breast cancer. A randomized clinical trial is needed for the evaluation of postoperative irradiation for breast cancer. (Namekawa, K.)

Food problems and food irradiation, recent trend

International Nuclear Information System (INIS)

1990-01-01

Food irradiation is to contribute to the stable security of foodstuffs which is the fundamental condition of human survival by improving the preservation of foodstuffs and food sanitation utilizing the biological effect due to irradiation. The research and development have been carried out internationally since 1950s, but after the safety declaration of irradiated foods in 1980 by the international organ concerned, the permission and practical use for foods in various foreign countries, the technology transfer to developing countries and so on have been advanced. At present, food irradiation is permitted in 38 countries, and the practical irradiation is carried out in 24 countries. In Japan, the irradiation of potatoes to prevent germination was permitted in 1972, and the practical irradiation on potatoes of yearly 15,000 t is carried out. In the near future, irradiated foods will appear in international foodstuff market, and Japan which imports foodstuffs must cope with them. Foodstuffs and the safety, food irradiation, the soundness of irradiated foods, food irradiation in various foreign countries and Japan, the trend of international organs and the criticism of food irradiation are reported. (K.I.)

Irradiation creep in simple binary alloys

International Nuclear Information System (INIS)

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

1981-07-01

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

Gamma irradiation service in Mexico

International Nuclear Information System (INIS)

Liceaga C, G.; Martinez A, L.; Mendez T, D.; Ortiz A, G.; Olvera G, R.

1997-01-01

In 1980 it was installed in Mexico, on the National Institute of Nuclear Research, an irradiator model J S-6500 of a canadian manufacture. Actually, this is the greatest plant in the Mexican Republic that offers a gamma irradiation process at commercial level to diverse industries. However, seeing that the demand for sterilize those products were not so much as the irradiation capacity it was opted by the incursion in other types of products. During 17 years had been irradiated a great variety of products grouped of the following form: dehydrated foods, disposable products for medical use, cosmetics, medicaments, various. Nowadays the capacity of the irradiator is saturated virtue of it is operated the 24 hours during the 365 days of the year and only its operation is suspended by the preventive and corrective maintenance. However, the fresh food market does not be attended since this irradiator was designed for doses greater than 10 kGy (1.0 Mrad)

Fracture toughness of irradiated beryllium

International Nuclear Information System (INIS)

Beeston, J.M.

1978-01-01

The fracture toughness of nuclear grade hot-pressed beryllium upon irradiation to fluences of 3.5 to 5.0 x 10 21 n/cm 2 , E greater than 1 MeV, was determined. Procedures and data relating to a round-robin test contributing to a standard ASTM method for unirradiated beryllium are discussed in connection with the testing of irradiated specimens. A porous grade of beryllium was also irradiated and tested, thereby enabling some discrimination between the models for describing the fracture toughness behavior of porous beryllium. The fracture toughness of unirradiated 2 percent BeO nuclear grade beryllium was 12.0 MPa m/sup 1 / 2 /, which was reduced 60 percent upon irradiation at 339 K and testing at 295 K. The fracture toughness of a porous grade of beryllium was 13.1 MPa m/sup 1 / 2 /, which was reduced 68 percent upon irradiation and testing at the same conditions. Reasons for the reduction in fracture toughness upon irradiation are discussed

Cytologic studies on irradiated gestric cancer cells

Energy Technology Data Exchange (ETDEWEB)

Isono, S; Takeda, T; Amakasu, H; Asakawa, H; Yamada, S [Miyagi Prefectural Adult Disease Center, Natori (Japan)

1981-06-01

The smears of the biopsy and resected specimens obtained from 74 cases of irradiated gastric cancer were cytologically analyzed for effects of irradiation. Irradiation increased the amount of both necrotic materials and neutrophils in the smears. Cancer cells were decreased in number almost in inverse proportion to irradiation dose. Clusters of cancer cells shrank in size and cells were less stratified after irradiation. Irradiated cytoplasms were swollen, vacuolated and stained abnormally. Irradiation with less than 3,000 rads gave rise to swelling of cytoplasms in almost all cases. Nuclei became enlarged, multiple, pyknotic and/or stained pale after irradiation. Nuclear swelling was more remarkable in cancer cells of differentiated adenocarcinomas.

TU-H-CAMPUS-TeP2-02: FLASH Irradiation Improves the Therapeutic Index Following GI Tract Irradiation

International Nuclear Information System (INIS)

Schueler, E; Trovati, S; King, G; Lartey, F; Rafat, M; Loo, B; Maxim, P

2016-01-01

Purpose: To investigate and characterize the radiobiological effectiveness of very high dose rate radiotherapy (FLASH) compared to conventional irradiation in an in vivo model. Methods: The gastrointestinal (GI) tract of C57BL/6 mice were irradiated with doses ranging between 10 and 18 Gy using a custom stereotactic jig. A Varian Clinac 21EX was modified to allow dose rates ranging from 0.05 to 240 Gy/s at the position of the mirror. With the gantry at 180 degrees, the jig holding the individual animals was placed above the mirror to take advantage of the reduced source to target distance. Mice were irradiated with 20MeV electrons. Following irradiation, the mice were monitored twice daily for morbidity and daily for weight changes. Results: Mice irradiated with FLASH irradiation had lower weight loss compared to the mice receiving conventional irradiation. Following FLASH irradiation, a maximum weight loss of ∼20% was observed at day 6 with subsequent recovery, while following conventional irradiation, higher weight losses was observed with fewer instances of recovery. Concerning survival, all mice in the conventionally irradiated groups had a 100% mortality in the range of 15.5–18 Gy, while the mice irradiated with FLASH irradiation had a 100% survival in the same range. Conclusion: These results have demonstrated proof of principle that FLASH irradiations have a dramatic impact on the overall survival of mice following GI tract irradiations. If the increase in the therapeutic window can be validated and understood, this would revolutionize the field of radiation oncology and lead to increased cure rates with reduced side effects following treatment, resulting in increased quality of life for cancer survivors. Funding: DoD, Award#:W81XWH-14-1-0014, Weston Havens Foundation, Bio-X (Stanford University), the Office of the Dean of the Medical School, the Office of the Provost (Stanford University), and the Swedish Childhood Cancer Foundation; BL and PM are

TU-H-CAMPUS-TeP2-02: FLASH Irradiation Improves the Therapeutic Index Following GI Tract Irradiation

Energy Technology Data Exchange (ETDEWEB)

Schueler, E; Trovati, S; King, G; Lartey, F; Rafat, M; Loo, B; Maxim, P [Stanford University School of Medicine, Palo Alto, California (United States)

2016-06-15

Purpose: To investigate and characterize the radiobiological effectiveness of very high dose rate radiotherapy (FLASH) compared to conventional irradiation in an in vivo model. Methods: The gastrointestinal (GI) tract of C57BL/6 mice were irradiated with doses ranging between 10 and 18 Gy using a custom stereotactic jig. A Varian Clinac 21EX was modified to allow dose rates ranging from 0.05 to 240 Gy/s at the position of the mirror. With the gantry at 180 degrees, the jig holding the individual animals was placed above the mirror to take advantage of the reduced source to target distance. Mice were irradiated with 20MeV electrons. Following irradiation, the mice were monitored twice daily for morbidity and daily for weight changes. Results: Mice irradiated with FLASH irradiation had lower weight loss compared to the mice receiving conventional irradiation. Following FLASH irradiation, a maximum weight loss of ∼20% was observed at day 6 with subsequent recovery, while following conventional irradiation, higher weight losses was observed with fewer instances of recovery. Concerning survival, all mice in the conventionally irradiated groups had a 100% mortality in the range of 15.5–18 Gy, while the mice irradiated with FLASH irradiation had a 100% survival in the same range. Conclusion: These results have demonstrated proof of principle that FLASH irradiations have a dramatic impact on the overall survival of mice following GI tract irradiations. If the increase in the therapeutic window can be validated and understood, this would revolutionize the field of radiation oncology and lead to increased cure rates with reduced side effects following treatment, resulting in increased quality of life for cancer survivors. Funding: DoD, Award#:W81XWH-14-1-0014, Weston Havens Foundation, Bio-X (Stanford University), the Office of the Dean of the Medical School, the Office of the Provost (Stanford University), and the Swedish Childhood Cancer Foundation; BL and PM are

Flux and energy deposition distribution studies inside the irradiation room of the portuguese 60Co irradiation facility

International Nuclear Information System (INIS)

Portugal, Luis; Oliveira, Carlos

2008-01-01

Full text: In December 2003 the irradiator of the Portuguese 60 Co irradiation facility, UTR, was replenished. Eighteen new sources were loaded and the older ones (156) were rearranged. The result was an irradiator with about 10.2 P Bq of total activity. The active area of the irradiator has also increased. Now it uses twenty five of the thirty tubes of the source rack, nine more than in the previous geometry. This facility was designed mainly for sterilisation of medical devices. However it is also used for the irradiation of other products such as cork stoppers, plastics and a limited number of food and feed. The purpose of this work is to perform dosimetric studies inside the irradiation room of a 60 Co irradiation facility, particularly, the flux and energy deposition distributions. The MCNPX code was used for the simulation of the facility. The track average mesh tally capabilities of MCNPX were used to plot the photon flux and energy deposition distributions. This tool provides a fast way for flux and energy deposition mapping. The absorbed dose distribution near the walls of the irradiation room was also calculated. Instead of using meshtallys as before, the average absorbed dose inside boxes lined with the walls was determined and afterwards a plot of its distribution was made. The absorbed dose rates obtained ranged from 5 to 500 Gy.h -1 depending on material being irradiated in process and the location on the wall. These positions can be useful for fixed irradiation purposes. Both dosimetric studies were done considering two different materials being irradiated in the process: cork stoppers and water, materials with quite different densities (0.102 and 1 g.cm-3, respectively). These studies showed some important characteristics of the radiation fields inside the irradiation room, namely its spatial heterogeneity. Tunnelling and shadow effects were enhanced when the product boxes increases its density. Besides a deeper dosimetric understanding of the

Similarity between the effects of carbon-ion irradiation and X-irradiation on the development of rat brain

International Nuclear Information System (INIS)

Inouye, Minoru; Hayasaka, Shizu; Murata, Yoshiharu; Takahashi, Sentaro; Kubota, Yoshihisa

2000-01-01

The effects of carbon-ion irradiation and X-irradiation on the development of rat brain were compared. Twenty pregnant rats were injected with bromodeoxyuridine (BrdU) at 9 pm on day 18 pregnancy and divided into five groups. Three hours after injection (day 19.0) one group was exposed to 290 MeV/u carbon-ion radiation by a single dose of 1.5 Gy. Other groups were exposed to X-radiation by 1.5, 2.0 or 2.5 Gy, or sham-treated, respectively. Fetuses were removed from one dam in each group 8 h after exposure and examined histologically. Extensive cell death was observed in the brain mantle from the irradiated groups. The cell death after 1.5 Gy carbon-ion irradiation was remarkably more extensive than that after 1.5 Gy X-irradiation, but comparable to that after 2.0 Gy or 2.5 Gy X-irradiation. The remaining rats were allowed to give birth and the offspring were sacrificed at 6 weeks of age. All of the irradiated offspring manifested microcephaly. The size of the brain mantle exposed to 1.5 Gy carbon-ion radiation was significantly smaller than that exposed to 1.5 Gy X-radiation and larger than that exposed to 2.5 Gy X-radiation. A histological examination of the cerebral cortex revealed that cortical layers II-IV were malformed. The defect by 1.5 Gy carbon-ion irradiation was more severe than that by the same dose of X-irradiation. Although the BrdU-incorporated neurons were greatly reduced in number in all irradiated groups, these cells reached the superficial area of the cortex. These findings indicated that the effects of both carbon-ion irradiation and X-irradiation on the development of rat brain are similar in character, and the effect of 1.5 Gy carbon-ion irradiation compares to that of 2.0-2.5 Gy X-irradiation. (author)

Simulation of gamma-ray irradiation of lettuce leaves in a 137Cs irradiator using MCNP

International Nuclear Information System (INIS)

Kim, Jongsoon; Moreira, Rosana G.; Braby, Leslie A.

2010-01-01

Ionizing radiation effectively reduces the number of common microbial pathogens in fresh produce. However, the efficacy of the process for pathogens internalized into produce tissue is unknown. The objective of this study was to understand gamma irradiation of lettuce leaf structure exposed in a 137 Cs irradiator using MCNP. The simulated 137 Cs irradiator is a self-shielded device, and its geometry and sources are described in the MCNP input file. When the irradiation chamber is filled with water, lower doses are found at the center of the irradiation volume and the dose uniformity ratio (maximum dose/minimum dose) is 1.76. For randomly oriented rectangular lettuce leaf segments in the irradiation chamber, the dose uniformity ratio is 1.25. It shows that dose uniformity in the Cs irradiator is strongly dependent of the density of the sample. To understand dose distribution inside the leaf, we divided a lettuce leaf into a low density (flat) region (0.72 g/cm 3 ) and high density (rib) region (0.86 g/cm 3 ). Calculated doses to the rib are 61% higher than doses to the flat region of the leaf. This indicates that internalized microorganisms can be inactivated more easily than organisms on the surface. This study shows that irradiation can effectively reduce viable microorganism internalized in lettuce. (author)

The ARBOR irradiation project

International Nuclear Information System (INIS)

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

2002-01-01

The irradiation project 'ARBOR', for 'Associated Reactor Irradiation in BOR 60', includes 150 mini-tensile/low cycle fatigue specimens and 150 mini-Charpy (KLST) specimens of nine different RAFM steels. Specimens began irradiation on 22 November 2000 in an specially designed irradiation rig in BOR 60, in a fast neutron flux (>0.1 MeV) of 1.8x10 15 n/cm 2 s and with direct sodium cooling at a temperature less than 340 deg. C. Tensile, low cycle fatigue and Charpy specimens of the following materials are included: EUROFER 97, F82H mod., OPTIFER IVc, EUROFER 97 with different boron contents, ODS-EUROFER 97, as well as EUROFER 97 electron-beam welded and reference bulk material, from NRG, Petten

Evaluation of spaghetti prepared from irradiated and non-irradiated semolina flour, defatted soybean and wheat germ

International Nuclear Information System (INIS)

Nassef, A.E.; Assem, N.H.

2005-01-01

The aim of the present investigation was to produce spaghetti from semolina flour supplemented with 5, 7.5 and 10% wheat germ and 5, 7.5 and 10% defatted soybean flours and gamma irradiated at 5 and 10 KGy to improve its nutritive value. Part of the blend was left without irradiation to serve as control. All samples of spaghetti were analyzed for chemical composition, color, cooking properties, sensory evaluation and amino acids contents. The results of chemical composition showed high protein and fat contents by increasing the percentage of addition for wheat germ and defatted soybean, which irradiated and non-irradiated, in spaghetti. Sensory evaluation and cooking properties for spaghetti supplemented with 5 and 7.5% non-irradiated or irradiated (5 KGy) defatted soybean gave the best values comparing with supplementation by 10% non-irradiated and irradiated with 10 KGy. The best treatments, based on sensory evaluation results, were analyzed for amino acids. Essential and non-essential amino acid levels were found to be higher in samples supplemented with wheat germ and defatted soybean when compared with control, which was prepared from semolina only

Development of Irradiation Procedure for Gamma Irradiation Chamber Bio beam GM 8000

International Nuclear Information System (INIS)

Shuhaimi Shamsudin; Affrida Abu Hassan; Zaiton Ahmad; Abdul Rahim Harun; Ahmad Zainuri Mohd Dzomir

2015-01-01

Bio Beam GM 8000 gamma irradiation chamber obtained a conditional approval to operate on March 27, 2012, and later acquired a full approval on December 13, 2012. The objective for the procurement of this gamma chamber is to develop an acute irradiation facility for biological samples, including plants tissues, insects, pupae, microorganisms, as well as animal and human cells. To ensure a smooth and efficient operation, irradiation procedures were developed and improved over time. This paper discusses the operation and management of the Bio Beam GM 8000 facility, including irradiation procedures and sample preparation, application for services through online e-client system, consultancy, quality assurance and information dissemination to internal as well as external clients. In addition, this paper also discusses the potential, constraints and improvement measures taken to optimize the use of this facility in order to meet its objectives. (author)

Decommissioning of an Irradiator MPX-γ - 25M and a neutron Irradiator

International Nuclear Information System (INIS)

Soguero, Dania; Guerra, Mercedes; Prieto, Enrique; Desdin, Luis

2013-01-01

In this paper a technology is developed with its procedures in radiation protection to ensure the safety of the process of decommissioning of two irradiators. Both processes are described, the process of decommissioning of a neutron Irradiator 4. 44·10 11 Bq, employed in the vegetal radio mutagenesis, and disassembling of an installation of gamma irradiation of 3.33 * 10 12 Bq, self-shielded of category I, model MPX - γ - 25 M. The specific objectives are: a) identify aspects of the contractual assurance, of human and technical resources, b) to evaluate the radiological situation of the process and c) analyze the potential radiological extraordinary events in each of the steps of the process, ensuring the right answers. Evaluation of radiological successful events described can be considered as reference to address the process of disassembling of other similar irradiators

EPR measurements in irradiated polyacetylene

International Nuclear Information System (INIS)

Hola, O.; Foeldesova, M.

1990-01-01

The influence of γ-irradiation on the paramagnetic properties of polyacetylene, and the dependence of the EPR spectra on the radiation dose in samples of irradiated polyacetylene were studied. The measurements show that no essential changes of the spin mobility occurred during irradiation. (author) 3 refs.; 2 figs

Bakery products from irradiated and unirradiated eggs - detection of irradiation in a processed food

International Nuclear Information System (INIS)

Pfordt, J.; Grabowski, H.U. von

1995-01-01

The detection of radiation-specific degradation products in fat has become an established method which has successfully been applied to egg products. This study is making evident the detectability of irradiated eggs as an ingredient of specified processed foods. Tart layers were produced from both irradiated and non-irradiated liquid whole egg. When the fat components were isolated from the tart layers and investigated by GC/MS, the presence of irradiated eggs could clearly be shown. While the radiation-induced hydrocarbons and 2-alkylcyclobutanones could not be found in unirradiated samples, tart layers from irradiated eggs contained these substances. Especially for the hydrocarbons a satisfying correlation between radiation dose and concentration could be observed. The concentrations of radiation-induced compounds were generally lower in the tart layers than in the liquid egg samples they had been produced from. (orig.) [de

Status of food irradiation worldwide

International Nuclear Information System (INIS)

Loaharanu, P.

1992-01-01

The past four decades have witnessed the steady development of food irradiation technology - from laboratory-scale research to full-scale commercial application. The present status of this technology, approval for processing food items in 37 countries and commerical use of irradiated food in 24 countries, will be discussed. The trend in the use of irradiation to overcome certain trade barriers such as quarantine and hygiene will be presented. Emphasis will be made on the use of irradiation as an alternative to chemical treatments of food. (orig.) [de

Consumer acceptance of irradiated food

Energy Technology Data Exchange (ETDEWEB)

Loaharanu, P [Head, Food Preservation Section, Joint FAO/ IAEA Division of Nuclear Techniques in Food and Agriculture, Wagramerstr. 5, A-1400, Vienna (Austria)

1998-12-31

There was a widely held opinion during the 1970`s and 1980`s that consumers would be reluctant to purchase irradiated food, as it was perceived that consumers would confuse irradiated food with food contaminated by radionuclides. Indeed, a number of consumer attitude surveys conducted in several western countries during these two decades demonstrated that the concerns of consumers on irradiated food varied from very concerned to seriously concerned.This paper attempts to review parameters conducting in measuring consumer acceptance of irradiated food during the past three decades and to project the trends on this subject. It is believed that important lessons learned from past studies will guide further efforts to market irradiated food with wide consumer acceptance in the future. (Author)

Consumer acceptance of irradiated food

Energy Technology Data Exchange (ETDEWEB)

Loaharanu, P. [Head, Food Preservation Section, Joint FAO/ IAEA Division of Nuclear Techniques in Food and Agriculture, Wagramerstr. 5, A-1400, Vienna (Austria)

1997-12-31

There was a widely held opinion during the 1970`s and 1980`s that consumers would be reluctant to purchase irradiated food, as it was perceived that consumers would confuse irradiated food with food contaminated by radionuclides. Indeed, a number of consumer attitude surveys conducted in several western countries during these two decades demonstrated that the concerns of consumers on irradiated food varied from very concerned to seriously concerned.This paper attempts to review parameters conducting in measuring consumer acceptance of irradiated food during the past three decades and to project the trends on this subject. It is believed that important lessons learned from past studies will guide further efforts to market irradiated food with wide consumer acceptance in the future. (Author)

Consumer acceptance of irradiated food

International Nuclear Information System (INIS)

Loaharanu, P.

1997-01-01

There was a widely held opinion during the 1970's and 1980's that consumers would be reluctant to purchase irradiated food, as it was perceived that consumers would confuse irradiated food with food contaminated by radionuclides. Indeed, a number of consumer attitude surveys conducted in several western countries during these two decades demonstrated that the concerns of consumers on irradiated food varied from very concerned to seriously concerned.This paper attempts to review parameters conducting in measuring consumer acceptance of irradiated food during the past three decades and to project the trends on this subject. It is believed that important lessons learned from past studies will guide further efforts to market irradiated food with wide consumer acceptance in the future. (Author)

Analysis of Low Dose Irradiation Damages in Structural Ferritic/Martensitic Steels by Proton Irradiation and Nanoindentation

International Nuclear Information System (INIS)

Waseem, Owais A.; Ryu, Ho Jin; Park, Byong Guk; Jeong, Jong Ryul; Maeng, Cheol Soo; Lee, Myoung Goo

2016-01-01

As a result, ferritic-martensitic steels find applications in the in-core and out-of-core components which include ducts, piping, pressure vessel and cladding, etc. Due to ferromagnetism of F/M steel, it has been successfully employed in solenoid type fuel injector. Although the irradiation induced degradation in ferritic martensitic steels is lower as compare to (i) reduced activation steels, (ii) austenitic steels and (iii) martensitic steels, F/M steels are still prone to irradiation induced hardening and void swelling. The irradiation behavior may become more sophisticated due to transmutation and production of helium and hydrogen. The ductile to brittle transition temperature of F/M steels is also expected to increase due to irradiation. These irradiation induced degradations may deteriorate the integrity of F/M components. As a result of these investigations, it has found that the F/M steels experience no irradiation hardening above 400 .deg. C, but below this temperature, up to 350 .deg. C, weak hardening is observed. The irradiation hardening becomes more pronounced below 300 .deg. C. Moreover, the irradiation hardening has also found dependent upon radiation damage. The hardening was found increasing with increasing dose. Due to pronounced irradiation hardening below 300 .deg. C and increasing radiation damage with increasing dose (even at low dpa), it is required to investigate the post irradiation mechanical properties of F/M steel, in order to confirm its usefulness in structural and magnetic components which experience lifetime doses as low as 1x10"-"5 dpa.

Analysis of Low Dose Irradiation Damages in Structural Ferritic/Martensitic Steels by Proton Irradiation and Nanoindentation

Energy Technology Data Exchange (ETDEWEB)

Waseem, Owais A.; Ryu, Ho Jin; Park, Byong Guk [KAIST, Daejeon (Korea, Republic of); Jeong, Jong Ryul [Chungnam University, Daejeon (Korea, Republic of); Maeng, Cheol Soo; Lee, Myoung Goo [KEPCO, Daejeon (Korea, Republic of)

2016-05-15

As a result, ferritic-martensitic steels find applications in the in-core and out-of-core components which include ducts, piping, pressure vessel and cladding, etc. Due to ferromagnetism of F/M steel, it has been successfully employed in solenoid type fuel injector. Although the irradiation induced degradation in ferritic martensitic steels is lower as compare to (i) reduced activation steels, (ii) austenitic steels and (iii) martensitic steels, F/M steels are still prone to irradiation induced hardening and void swelling. The irradiation behavior may become more sophisticated due to transmutation and production of helium and hydrogen. The ductile to brittle transition temperature of F/M steels is also expected to increase due to irradiation. These irradiation induced degradations may deteriorate the integrity of F/M components. As a result of these investigations, it has found that the F/M steels experience no irradiation hardening above 400 .deg. C, but below this temperature, up to 350 .deg. C, weak hardening is observed. The irradiation hardening becomes more pronounced below 300 .deg. C. Moreover, the irradiation hardening has also found dependent upon radiation damage. The hardening was found increasing with increasing dose. Due to pronounced irradiation hardening below 300 .deg. C and increasing radiation damage with increasing dose (even at low dpa), it is required to investigate the post irradiation mechanical properties of F/M steel, in order to confirm its usefulness in structural and magnetic components which experience lifetime doses as low as 1x10{sup -5} dpa.

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

Energy Technology Data Exchange (ETDEWEB)

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

1996-10-01

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

HANARO fuel irradiation test(II)

Energy Technology Data Exchange (ETDEWEB)

Sohn, D. S.; Kim, H. R.; Chae, H. T.; Lee, B. C.; Lee, C. S.; Kim, B. G.; Lee, C. B.; Hwang, W

2001-04-01

In order to fulfill the requirement to prove HANARO fuel integrity when irradiated at a power greater than 112.8 kW/m, which was imposed during HANARO licensing, and to verify the irradiation performance of HANARO fuel, the in-pile irradiation test of HANARO fuel has been performed. Two types of test fuel, the un-instrumented Type A fuel for higher burnup irradiation in shorter period than the driver fuel and the instrumented Type B fuel for higher linear heat rate and precise measurement of irradiation conditions, have been designed and fabricated. The test fuel assemblies were irradiated in HANARO. The two Type A fuel assemblies were intended to be irradiated to medium and high burnup and have been discharged after 69.9 at% and 85.5 at% peak burnup, respectively. Type B fuel assembly was intended to be irradiatied at high power with different instrumentations and achieved a maximum power higher than 120 kW/m without losing its integrity and without showing any irregular behavior. The Type A fuel assemblies were cooled for about 6 months and transported to the IMEF(Irradiated Material Examination Facility) for consequent evaluation. Detailed non-destructive and destructive PIE (Post-Irradiation Examination), such as the measurement of burnup distribution, fuel swelling, clad corrosion, dimensional changes, fuel rod bending strength, micro-structure, etc., has been performed. The measured results have been analysed/compared with the predicted performance values and the design criteria. It has been verified that HANARO fuel maintains proper in-pile performance and integrity even at the high power of 120 kw/m up to the high burnup of 85 at%.

Interstitial irradiation for craniopharyngioma

International Nuclear Information System (INIS)

Barlas, O.; Bayindir, C.; Can, M.

2000-01-01

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

Food irradiation in China

International Nuclear Information System (INIS)

Zhu Jiang

1994-01-01

In this paper, the author discussed the recent situation of food irradiation in China, its history, facilities, clearance, commercialization, and with emphasis on market testing and public acceptance of irradiated food. (author)

Heavy-Section Steel Irradiation Program

International Nuclear Information System (INIS)

Corwin, W.R.

1990-08-01

The primary goal of the Heavy-Section Steel Irradiation Program is to provide a thorough, quantitative assessment of the effects of neutron irradiation on the material behavior (particularly the fracture toughness properties) of typical pressure-vessel steels as they relate to light-water-reactor pressure-vessel integrity. The program includes direct continuation of irradiation studies previously conducted by the Heavy-Section Steel Technology Program augmented by enhanced examinations of the accompanying microstructural changes. Effects of specimen size; material chemistry; product form and microstructure; irradiation fluence, flux, temperature, and spectrum; and postirradiation annealing are examined on a wide range of fracture properties. Detailed statistical analyses of the fracture data on K Ic shift of high-copper welds were performed. Analysis of the first phase of irradiated crack-arrest testing on high-copper welds was completed. Final analysis and publication of the results of the second phase of the irradiation studies on stainless steel weld-overlay cladding were completed. Determinations were made of the variations in chemistry and unirradiated RT NDT of low upper-shelf weld metal from the Midland reactor. Final analyses were performed on the Charpy impact and tensile data from the Second and Third Irradiation series on low upper-shelf welds, and the report on the series was drafted. A detailed survey of existing data on microstructural models and data bases of irradiation damage was performed, and initial development of a reaction-rate-based model was completed. 40 refs., 7 figs., 4 tabs

Research on food irradiation in Indonesia

International Nuclear Information System (INIS)

Hilmy, N.; Maha, M.; Chosdu, R.

1986-01-01

Studies on various aspects of food irradiation have been done in Indonesia since 1968, mainly at the Centre for the Application of Isotopes and Radiation, National Atomic Energy Agency of Indonesia. Three irradiation facilities available at the Centre are gamma cell-220, panoramic batch irradiator, and latex irradiator with the present source capacities of about 1.1, 40, and 163.8 kCi Co-60, respectively. In this paper, the present status of research and development on irradiation is presented, covering (1) spices and medicinal plants, (2) rice, wheat flour and coffee bean, (3) fish and fishery products, (4) animal feed, and (5) ongoing projects including fresh fruits, cacao beans, and cashew nut. The Sub-Committee for the Control of Irradiation of Food and Medical Products, set up in August 1984, has prepared the draft of recommendations regarding the regulation for application of food irradiation in Indonedia and the draft of Regulation for the Control of and Trade in Irradiated Food and Traditional Drug to be issued by the government. (Namekawa, K.)

Research to connect the ozone monitor into irradiation system at Hanoi Irradiation Centre

International Nuclear Information System (INIS)

Le Van Huy; Pham Duy Duong; Nguyen Dinh Hung; Vu Quoc Dat

2013-01-01

Since 2006, in order to develop radiation technology, Vietnam Atomic Energy Institute has supported Hanoi Irradiation Centre a Project titled: Upgrading the irradiation facility. According to the Project, equipment have been replaced by a new one so that the facility could be suitable for treatment of products. The facility was designed and produced by the former Russia experts. Under normal operating conditions, we are protected by shielding, detection systems, and safety procedures. A system of interlocks prevents unauthorized entry into the radiation chamber when the source is exposed. However, interlocks system have not been warning and preventing ozone gas that can affect human health. So we are having an upgrade as connecting the ozone monitor into irradiation system at Hanoi Irradiation Centre. (author)

Legislations the field of food irradiation

International Nuclear Information System (INIS)

1987-05-01

An outline is given of the national legislation in 39 countries in the field of food irradiation. Where available the following information is given for each country: form of legislation, object of legislation including information on the irradiation treatment, the import and export trade of irradiated food, the package labelling and the authorization and control of the irradiation procedures

Gemstone enhancing dedicated gamma irradiator development

International Nuclear Information System (INIS)

Omi, Nelson Minoru

2006-01-01

The gemstones gamma irradiation process to enhance the color is widely accepted for the jewelry industry. These gems are processed in conventional industrial gamma irradiation plant which are optimized for other purposes, using underwater irradiation devices with high rejection rate due to it's poor dose uniformity. A new conception design, which states the working principles and manufacturing ways of the device, was developed in this work. The suggested device's design is based on the rotation of cylindrical baskets and their translation in circular paths inside and outside a cylindrical source rack as a planetary system. The device is meant to perform the irradiation in the bottom of the source storage pool, where the sources remain always shielded by the water layer. The irradiator matches the Category III IAEA classification. To verify the physical viability of the basic principle, tests with rotating cylindrical baskets were performed in the Multipurpose Irradiator raised in the CTR, IPEN. Also, simulations using the CADGAMMA software, adapted to simulate underwater irradiations were performed. With the definitive irradiator, the irradiation quality will be enhanced with better dose control and the production costs will be significantly lower than market prices due to the intended treatment device's optimization. (author)

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

International Nuclear Information System (INIS)

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

2004-01-01

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

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

Energy Technology Data Exchange (ETDEWEB)

Farah, K. E-mail: k.farah@cnstn.rnrt.tn; Kuntz, F.; Kadri, O.; Ghedira, L

2004-10-01

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

Effectiveness of thermoluminescence analysis to detect low quantity of gamma-irradiated component in non-irradiated mushroom powders

International Nuclear Information System (INIS)

Akram, Kashif; Ahn, Jae-Jun; Shahbaz, Hafiz Muhammad; Jo, Deokjo; Kwon, Joong-Ho

2013-01-01

Gamma-irradiated (0–10 kGy) dried mushrooms (Lentinus edodes) powders were mixed at different ratios (1–10%) in the non-irradiated samples and investigated using photostimulated-luminescence (PSL), electron spin resonance (ESR) and thermoluminescence (TL) techniques. The PSL results were negative for all samples at 1% mixing ratio, whereas intermediate results were observed for the samples containing 5% or 10% irradiated component with the exception (positive) of 10% mixing of 10 kGy-irradiated sample. The ESR analysis showed the presence of crystalline sugar radicals in the irradiated samples but the radiation-specific spectral features were absent in the mixed samples. TL analysis showed the radiation-specific TL glow curves; however, the complicated results were observed at 1% mixing of 2 and 5 kGy-irradiated samples, which required careful evaluations to draw the final conclusion about the irradiation status of the samples. TL ratios could only confirm the results of samples with 5% and 10% mixing of 10 kGy, and 10% mixing of 5 kGy-irradiated components. SEM-EDX analysis showed that feldspar and quartz were major contaminating minerals, responsible for the radiation-specific luminescence characteristics. -- Highlights: ► Detection of irradiated food is important to enforce the applied regulations. ► The effectiveness of TL analysis was investigated to detect irradiated component. ► The TL results were compared with those from PSL and ESR analysis. ► TL analysis was most effective to characterize the irradiation status of samples. ► SEM-EDX analysis showed feldspar and quartz as the main source of TL properties

Effectiveness of thermoluminescence analysis to detect low quantity of gamma-irradiated component in non-irradiated mushroom powders

Energy Technology Data Exchange (ETDEWEB)

Akram, Kashif [School of Food Science and Biotechnology, Kyungpook National University, Daegu 702-701 (Korea, Republic of); Institute of Food Science and Nutrition, University of Sargodha, Sargodha 40100 (Pakistan); Ahn, Jae-Jun [School of Food Science and Biotechnology, Kyungpook National University, Daegu 702-701 (Korea, Republic of); Shahbaz, Hafiz Muhammad [School of Food Science and Biotechnology, Kyungpook National University, Daegu 702-701 (Korea, Republic of); Institute of Food Science and Nutrition, University of Sargodha, Sargodha 40100 (Pakistan); Jo, Deokjo [School of Food Science and Biotechnology, Kyungpook National University, Daegu 702-701 (Korea, Republic of); Kwon, Joong-Ho, E-mail: jhkwon@knu.ac.kr [School of Food Science and Biotechnology, Kyungpook National University, Daegu 702-701 (Korea, Republic of)

2013-04-15

Gamma-irradiated (0–10 kGy) dried mushrooms (Lentinus edodes) powders were mixed at different ratios (1–10%) in the non-irradiated samples and investigated using photostimulated-luminescence (PSL), electron spin resonance (ESR) and thermoluminescence (TL) techniques. The PSL results were negative for all samples at 1% mixing ratio, whereas intermediate results were observed for the samples containing 5% or 10% irradiated component with the exception (positive) of 10% mixing of 10 kGy-irradiated sample. The ESR analysis showed the presence of crystalline sugar radicals in the irradiated samples but the radiation-specific spectral features were absent in the mixed samples. TL analysis showed the radiation-specific TL glow curves; however, the complicated results were observed at 1% mixing of 2 and 5 kGy-irradiated samples, which required careful evaluations to draw the final conclusion about the irradiation status of the samples. TL ratios could only confirm the results of samples with 5% and 10% mixing of 10 kGy, and 10% mixing of 5 kGy-irradiated components. SEM-EDX analysis showed that feldspar and quartz were major contaminating minerals, responsible for the radiation-specific luminescence characteristics. -- Highlights: ► Detection of irradiated food is important to enforce the applied regulations. ► The effectiveness of TL analysis was investigated to detect irradiated component. ► The TL results were compared with those from PSL and ESR analysis. ► TL analysis was most effective to characterize the irradiation status of samples. ► SEM-EDX analysis showed feldspar and quartz as the main source of TL properties.

AGC-2 Irradiation Report

Energy Technology Data Exchange (ETDEWEB)

Rohrbaugh, David Thomas [Idaho National Lab. (INL), Idaho Falls, ID (United States); Windes, William [Idaho National Lab. (INL), Idaho Falls, ID (United States); Swank, W. David [Idaho National Lab. (INL), Idaho Falls, ID (United States)

2016-06-01

The Next Generation Nuclear Plant (NGNP) will be a helium-cooled, very high temperature reactor (VHTR) with a large graphite core. In past applications, graphite has been used effectively as a structural and moderator material in both research and commercial high temperature gas cooled reactor (HTGR) designs.[ , ] Nuclear graphite H 451, used previously in the United States for nuclear reactor graphite components, is no longer available. New nuclear graphites have been developed and are considered suitable candidates for the new NGNP reactor design. To support the design and licensing of NGNP core components within a commercial reactor, a complete properties database must be developed for these current grades of graphite. Quantitative data on in service material performance are required for the physical, mechanical, and thermal properties of each graphite grade with a specific emphasis on data related to the life limiting effects of irradiation creep on key physical properties of the NGNP candidate graphites. Based on experience with previous graphite core components, the phenomenon of irradiation induced creep within the graphite has been shown to be critical to the total useful lifetime of graphite components. Irradiation induced creep occurs under the simultaneous application of high temperatures, neutron irradiation, and applied stresses within the graphite components. Significant internal stresses within the graphite components can result from a second phenomenon—irradiation induced dimensional change. In this case, the graphite physically changes i.e., first shrinking and then expanding with increasing neutron dose. This disparity in material volume change can induce significant internal stresses within graphite components. Irradiation induced creep relaxes these large internal stresses, thus reducing the risk of crack formation and component failure. Obviously, higher irradiation creep levels tend to relieve more internal stress, thus allowing the

Method of detecting irradiated pepper

International Nuclear Information System (INIS)

Doumaru, Takaaki; Furuta, Masakazu; Katayama, Tadashi; Toratani, Hirokazu; Takeda, Atsuhiko

1989-01-01

Spices represented by pepper are generally contaminated by microorganisms, and for using them as foodstuffs, some sterilizing treatment is indispensable. However, heating is not suitable to spices, accordingly ethylene oxide gas sterilization has been inevitably carried out, but its carcinogenic property is a problem. Food irradiation is the technology for killing microorganisms and noxious insects which cause the rotting and spoiling of foods and preventing the germination, which is an energy-conserving method without the fear of residual chemicals, therefore, it is most suitable to the sterilization of spices. In the irradiation of lower than 10 kGy, the toxicity test is not required for any food, and the irradiation of spices is permitted in 20 countries. However, in order to establish the international distribution organization for irradiated foods, the PR to consumers and the development of the means of detecting irradiation are the important subjects. The authors used pepper, and examined whether the hydrogen generated by irradiation remains in seeds and it can be detected or not. The experimental method and the results are reported. From the samples without irradiation, hydrogen was scarcely detected. The quantity of hydrogen generated was proportional to dose. The measuring instrument is only a gas chromatograph. (K.I.)

Special irradiation techniques

International Nuclear Information System (INIS)

Colomez, Gerard; Veyrat, J.F.

1981-01-01

Irradiation trials conducted on materials-testing reactors should provide a better understanding of the phenomena which characterize the working and evolution in time of electricity-generating nuclear reactors. The authors begin by outlining the objectives behind experimental irradiation (applied to the various nuclear chains) and then describe the special techniques deployed to achieve these objectives [fr

Food irradiation newsletter. Vol. 15, no. 2

International Nuclear Information System (INIS)

1991-10-01

This newsletter contains brief summaries of three coordinated research meetings held in 1991: irradiation in combination with other processes for improving food quality; application of irradiation technique for food processing in Africa; and food irradiation programme for Middle East and European countries. The first Workshop on Public Information on Food Irradiation is summarized, and a Coordinated Research Programme on Irradiation as a Quarantine Treatment of Mites, Nematodes and Insects other than Fruit Fly is announced. This issue also contains a report on the status of food irradiation in China, and a supplement lists clearances of irradiated foods. Tabs

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

NARCIS (Netherlands)

Marchioni, E; Horvatovich, P; Ndiaye, B; Miesch, M; Hasselmann, C

The application of the European Standards for the detection of irradiated food by thermo luminescence 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

Sterilization by gamma irradiation

International Nuclear Information System (INIS)

Reyes Frias, L.

1992-01-01

Since 1980 the National Institute of Nuclear Research counts with an Industrial Gamma Irradiator, for the sterilization of raw materials and finished products. Through several means has been promoted the use of this technology as alternative to conventional methods of sterilization as well as steam treatment and ethylene oxide. As a result of the made promotion this irradiator has come to its saturation limit being the sterilization irradiation one of the main services that National Institute of Nuclear Research offers to producer enterprises of disposable materials of medical use also of raw materials for the elaboration of cosmetic products and pharmaceuticals as well as dehydrated foods. It is presented the trend to the sterilization service by irradiation showed by the compilation data in a survey made by potential customers. (Author)

The ARBOR irradiation project

Energy Technology Data Exchange (ETDEWEB)

Petersen, C. E-mail: claus.petersen@imf.fzk.de; Shamardin, V.; Fedoseev, A.; Shimansky, G.; Efimov, V.; Rensman, J

2002-12-01

The irradiation project 'ARBOR', for 'Associated Reactor Irradiation in BOR 60', includes 150 mini-tensile/low cycle fatigue specimens and 150 mini-Charpy (KLST) specimens of nine different RAFM steels. Specimens began irradiation on 22 November 2000 in an specially designed irradiation rig in BOR 60, in a fast neutron flux (>0.1 MeV) of 1.8x10{sup 15} n/cm{sup 2} s and with direct sodium cooling at a temperature less than 340 deg. C. Tensile, low cycle fatigue and Charpy specimens of the following materials are included: EUROFER 97, F82H mod., OPTIFER IVc, EUROFER 97 with different boron contents, ODS-EUROFER 97, as well as EUROFER 97 electron-beam welded and reference bulk material, from NRG, Petten.

Food Irradiation Technology in the Philippines

International Nuclear Information System (INIS)

De Guzman, Zenaida M.

2015-01-01

The applications of ionizing radiation for the preservation of food and agricultural products by delaying ripening, destruction of insect pests and pathogenic microorganisms have shown great promise in the country. For more than 30 years, the Philippine Nuclear Research Institute (PNRI) in collaboration with other government and private sectors, has undertaken research and development studies and pilot and semi-commercial scale irradiation of foods. Some of the foods found to be benefit from the use of irradiation technology are mangoes and papayas for disinfestations and delay ripening; onions and garlic for inhibition of sprouting; spices and dehydrated products for reduction of microbial growth and rice and corn for insect and shelf-life extension. Two regulations approved by the Department of Health and the Bureau of Plant Industry are in place creating an enabling environment for food safety and trade of irradiated food. The conduct of awareness program in various parts of the country provided knowledge and information about the food irradiation technology. The Institute has been part of the international projects (IAEA and USDA) on the use of irradiation for sanity and phytosanitary treatment of food. The projects not only established the potential benefits of food irradiation for socio-economic development of the country but also built considerable capacity to properly treat foods. Some of the recent developments in the area of food irradiation include publication of Philippine National Standard (PNS) on Food Irradiation: Code of Good Irradiation Practices which will serve as a guide for stakeholders to irradiate food, a newly-established Electron Beam Facility to demonstrate the potential use of EB and a feasibility study of putting-up a commercial irradiation facility in the country. (author)

Effect of gamma irradiated parenchyma on the growth of irradiated potato tuber buds

International Nuclear Information System (INIS)

Fernandez Gonzalez, J.; Garcia Collantes, M. A.

1976-01-01

The development of buds greffed on irradiated potato parenchyma was studied. The irradiated parenchyma does not influence the sprouting capacity of buds, but it affects the way they develop. (Author) 9 refs

Effect of irradiation on carbohydrates content

International Nuclear Information System (INIS)

Chantharasakul, S.

1971-01-01

Effect of gamma radiation on vitamin C and total acidity contents of Hom Tong banana was described. There was a slight decrease in vitamin C contents in both irradiated and non-irradiated banana during storage. No difference was detected in term of vitamin C contents between irradiated and non-irradiated banana at any storage time. The total acidity of the banana increased with increasing time of storage owing to the ripening effect of the fruit. Higher total acidity content of non-irradiated banana during storage indicated the faster rate of ripening of the fruit

Lack of appetite for food irradiation

International Nuclear Information System (INIS)

Tacey, Elisabeth

1989-01-01

The British government has approved food irradiation in Britain on a much wider scale than has taken place previously. The implications for one of the companies currently offering a gamma irradiation service are explored. Irradiation is by a large Cobalt 60 source. Currently the customers are medical, cosmetic and packaging firms. It does not yet have the facilities necessary for large-scale food irradiation, nor does it expect a huge demand for food irradiation as customer resistance is strong. However some dry spices and herbs may be treated next year. (UK)

Control of food irradiation in Denmark

International Nuclear Information System (INIS)

Leth, T.

1996-01-01

In Denmark food irradiation is not allowed. However, with the consideration within EEC about directives regulating food irradiation and the development of methods for detection, it has been found necessary to ascertain that illegally irradiated foods are not found on the Danish market. Irradiation of spices is allowed in many countries even without being declared in the foods. It thus seemed logical to begin the control of food irradiation by screening a number of spices. This resulted in 1992 in the assessment of 105 samples and in 1993 of 48 samples. (author)

The post-irradiated examination of CANDU type fuel irradiated in the Institute for Nuclear Research TRIGA reactor

International Nuclear Information System (INIS)

Tuturici, I.L.; Parvan, M.; Dobrin, R.; Popov, M.; Radulescu, R.; Toma, V.

1995-01-01

This post-irradiation examination work has been done under the Research Contract No. 7756/RB, concluded between the International Atomic Energy Agency and the Institute for Nuclear Research. The paper contains a general description of the INR post-irradiation facility and methods and the relevant post-irradiation examination results obtained from an irradiated experimental CANDU type fuel element designed, manufactured and tested by INR in a power ramp test in the 100 kW Pressurised Water Irradiation Loop of the TRIGA 14 MW(th) Reactor. The irradiation experiment consisted in testing an assembly of six fuel elements, designed to reach a bumup of ∼ 200 MWh/kgU, with typical CANDU linear power and ramp rate. (author)

Irradiation effects on perfluorinated polymers

International Nuclear Information System (INIS)

Lappan, U.; Geissler, U.; Haeussler, L.; Pompe, G.; Scheler, U.; Lunkwitz, K.

2002-01-01

Complete text of publication follows. High-energy radiation affects the properties of polymers by chain scission and crosslinking reactions. Both types of reaction occur simultaneously in irradiated polymers. However, one process will usually predominate, depending on the chemical structure of the polymer and the irradiation conditions such as temperature and atmosphere. Polytetrafluoroethylene (PTFE) undergoes predominantly chain scission, if the irradiation is performed at room temperature. This shortcoming is exploited by converting PTFE into low molecular weight micropowders. The use of PTFE micropowders functionalized with COOH groups as additive in polyamides to improve the sliding properties of the materials has been studied. During the compounding process in a twin screw extruder the COOH groups of the irradiated PTFE react with the polyamides. For these studies, it became necessary to investigate the content of end groups in irradiated PTFE by FTIR and 19 F solid-state NMR. These date were used to calculate number-average molecular weights. The ratios of COOH groups to CF 3 groups are discussed in terms of the mechanism of PTFE degradation. If PTFE is irradiated at temperatures above its crystalline melting point in an oxygen-free atmosphere, branching and crosslinking occur. The dependence of radiation effects on perfluorinated copolymers (FEP, PFA) on temperature has been studied. Melt flow index measurements have shown that branching and crosslinking predominate over chain scission with increasing irradiation temperature both in FEP and in PFA. Quantitative analysis of 19 F solid-state NMR data has shown that the content of branching groups (>CF-) exceeds the content of end groups in the case of PFA irradiated above its crystalline melting point. The formation of COF and COOH groups in the irradiated PFA is interpreted as a result of partial degradation of perfluorovinyl ether comonomer units

Irradiation's potential for preserving food

International Nuclear Information System (INIS)

Morrison, R.M.

1986-01-01

The first experimental studies on the use of ionizing radiation for the preservation of foods were published over thirty years ago (1, 2) . After a period of high expectations and perhaps exaggerated optimism a series of disappointments occurred in the late '60s .The first company specifically created to operate a food irradiation plant, Newfield Products Inc, ran into financial difficulties and had to close its potato irradiation facility in 1966. The irradiator, designed to process 15,000t of potatoes per month for inhibition of sprouting, was in operation during one season only. In 1968 the US Food an Drug Administration refused approval for radiation-sterilisation of ham and withdrew the approval it had granted in 1963 for irradiated bacon. An International Project on the Irradiation of Fruit and Fruit juices, created in 1965 at Seibersdorf, Austria, with the collaboration or 9 countries, ended with general disappointment after three years. The first commercial grain irradiator, built in the Turkish harbour town of Iskenderun by the International Atomic Energy Agency with funds from the United Nations Development Program, never received the necessary operating licence from the Turkish Government and had to be dismantled in 1968. The US Atomic Energy Commission terminated its financial support to all research programmes on food irradiation in 1970. For a number of years, little chance seemed to remain that the new process would ever be practically used. However, research and development work was continued in a number of laboratories all over the world, and it appears that the temporary setbacks now have been overcome. Growing quantities of irradiated foods are being marketed in several countries and indications are that irradiated foods will eventually be as generally accepted as are frozen, dried or heatsterilised foods

China's move to food irradiation

International Nuclear Information System (INIS)

Wedekind, L.H.

1986-01-01

The Chinese officials outlined China's past and future directions at a recent international food irradiation seminar in Shanghai sponsored by the FAO and IAEA. The meeting was attended by about 170 participants from China and 22 other countries, primarily from the Asian and Pacific region. Three food irradiation plants currently are operating in the region and 14 more are planned over the next 5 years. It was reported that China continues to suffer high food losses, up to 30% for some commodities, primarily due to preservation and storage problems. In January 1986, the first of five regional irradiation facilities planned in China officially opened in Shanghai. The Shanghai irradiation centre plans to process up to 35,000 tons of vegetables a year, as well as some spices, fruits, and non-food products. The Ministry of Public Health has approved seven irradiated foods as safe human diets: rice, potatoes, onions, garlic, peanuts, mushrooms and pork sausages; approval for apples is expected shortly. The Chinese officials at the Shanghai meeting stressed their openness to foreign participation and cooperation in food irradiation's development

Identification methods for irradiated wheat

International Nuclear Information System (INIS)

Zhu Shengtao; Kume, Tamikazu; Ishigaki, Isao.

1992-02-01

The effect of irradiation on wheat seeds was examined using various kinds of analytical methods for the identification of irradiated seeds. In germination test, the growth of sprouts was markedly inhibited at 500Gy, which was not affected by storage. The decrease in germination percentage was detected at 3300Gy. The results of enzymatic activity change in the germ measured by Vita-Scope germinator showed that the seeds irradiated at 10kGy could be identified. The content of amino acids in ungerminated and germinated seeds were analyzed. Irradiation at 10kGy caused the decrease of lysine content but the change was small which need very careful operation to detect it. The chemiluminescence intensity increased with radiation dose and decreased during storage. The wheat irradiated at 10kGy could be identified even after 3 months storage. In the electron spin resonance (ESR) spectrum analysis, the signal intensity with the g value f 2.0055 of skinned wheat seeds increased with radiation dose. Among these methods, germination test was the most sensitive and effective for identification of irradiated wheat. (author)

Design of YCF-1 mobile γ irradiator

International Nuclear Information System (INIS)

Zhang Hehu; Wang Chuanzhen

1993-01-01

YCF-1 mobile irradiator has been designed by Beijing Institute of Nuclear Engineering of China and has been put into use in Jilin province. It can play an important role in extending irradiation technology in food irradiation, disinfestation, sterilization and quarantine. This paper describes the features and design considerations of a mobile irradiator. The irradiator uses a Cesium-137 source, the design loading capacity of the source is 9.25 PBq (250 kCi). The half-life of Cs-137 is 30.2 years and the source does not need replacing. The dose rate on the surface is 0.0025 mSv/h in accordance with national standards. The shielding of the irradiation room is a steel shell filled with lead. The thickness of lead is 18 cm. The irradiator is installed on a special flat truck. The weight of the irradiator is more than 80 tons. The main components and parts of the irradiator are: source, source racks and hoist, irradiation chamber, storage source chamber, the product's transport system, dose monitoring system, ventilation system and safety interlock system. (author)

Food Irradiation In Vietnam And Japan

International Nuclear Information System (INIS)

Tamikazy Kume

2011-01-01

In 2008, Japan Atomic Energy Commission of Cabinet Office performed the study of current status of food irradiation in the world. The results showed that the total quantity of irradiated foods in 2005 was 405,000 tons. Seven main countries for food irradiation were China, USA, Ukraine, Brazil, South Africa, Vietnam and Japan. In Japan, only the potato irradiation for sprout inhibition is continued more than 35 years since 1974 but the quantity is decreasing. On the other hand, the food irradiation of Vietnam has been developed rapidly in a short time to export the frozen seafood and fruit. This paper shows the status of food irradiation in Vietnam and Japan, and the progress in both countries after 2005. (author)

Promotion of food irradiation in Japan

International Nuclear Information System (INIS)

Kondo, Shunsuke; Tanaka, Shunichi; Tada, Mikitaro; Furuta, Masakazu; Kume, Tamikazu; Hayashi, Toru; Yamamoto, Kazuko

2007-01-01

Atomic Energy Commission of Japan has organized special symposia inviting citizens and consumers on food irradiation based on the report presented by expert members meeting discussing about food irradiation in various countries as well as in Japan. This document summarizes the lectures and talks presented at the symposia: usefulness of food irradiation, one of the most effective means of sterilization to ensure sanitary supplies and to prevent loss from spoilage, activities of the subcommittee consisting of experts of this field, a report of the open forum with public participants on food irradiation, present status of detection techniques for the irradiated foods, the role of phyto-sanitary measures in plant protection, and how to realize the consumer's free choices for irradiated foods. (S. Ohno)

Intercomparison of graphite irradiations

Energy Technology Data Exchange (ETDEWEB)

Hering, H; Perio, P; Seguin, M [Commissariat a l' Energie Atomique, Saclay (France).Centre d' Etudes Nucleaires

1959-07-01

While fast neutrons only are effective in damaging graphite, results of irradiations are more or less universally expressed in terms of thermal neutron fluxes. This paper attempts to correlate irradiations made in different reactors, i.e., in fluxes of different spectral compositions. Those attempts are based on comparison of 1) bulk length change and volume expansion, and 2) crystalline properties (e.g., lattice parameter C, magnetic susceptibility, stored energy, etc.). The methods used by various authors for determining the lattice constants of irradiated graphite are discussed. (author)

In-situ high temperature irradiation setup for temperature dependent structural studies of materials under swift heavy ion irradiation

International Nuclear Information System (INIS)

Kulriya, P.K.; Kumari, Renu; Kumar, Rajesh; Grover, V.; Shukla, R.; Tyagi, A.K.; Avasthi, D.K.

2015-01-01

An in-situ high temperature (1000 K) setup is designed and installed in the materials science beam line of superconducting linear accelerator at the Inter-University Accelerator Centre (IUAC) for temperature dependent ion irradiation studies on the materials exposed with swift heavy ion (SHI) irradiation. The Gd 2 Ti 2 O 7 pyrochlore is irradiated using 120 MeV Au ion at 1000 K using the high temperature irradiation facility and characterized by ex-situ X-ray diffraction (XRD). Another set of Gd 2 Ti 2 O 7 samples are irradiated with the same ion beam parameter at 300 K and simultaneously characterized using in-situ XRD available in same beam line. The XRD studies along with the Raman spectroscopic investigations reveal that the structural modification induced by the ion irradiation is strongly dependent on the temperature of the sample. The Gd 2 Ti 2 O 7 is readily amorphized at an ion fluence 6 × 10 12 ions/cm 2 on irradiation at 300 K, whereas it is transformed to a radiation-resistant anion-deficient fluorite structure on high temperature irradiation, that amorphized at ion fluence higher than 1 × 10 13 ions/cm 2 . The temperature dependent ion irradiation studies showed that the ion fluence required to cause amorphization at 1000 K irradiation is significantly higher than that required at room temperature irradiation. In addition to testing the efficiency of the in-situ high temperature irradiation facility, the present study establishes that the radiation stability of the pyrochlore is enhanced at higher temperatures

Irradiation-induced amorphization process in graphite

Energy Technology Data Exchange (ETDEWEB)

Abe, Hiroaki [Japan Atomic Energy Research Inst., Takasaki, Gunma (Japan). Takasaki Radiation Chemistry Research Establishment

1996-04-01

Effects of the element process of irradiation damage on irradiation-induced amorphization processes of graphite was studied. High orientation thermal decomposed graphite was cut about 100 nm width and used as samples. The irradiation experiments are carried out under the conditions of electronic energy of 100-400 KeV, ion energy of 200-600 KeV, ionic species Xe, Ar, Ne, C and He and the irradiation temperature at from room temperature to 900 K. The critical dose ({phi}a) increases exponentially with increasing irradiation temperature. The displacement threshold energy of graphite on c-axis direction was 27 eV and {phi}a{sup e} = 0.5 dpa. dpa is the average number of displacement to atom. The critical dose of ion irradiation ({phi}a{sup i}) was 0.2 dpa at room temperature, and amorphous graphite was produced by less than half of dose of electronic irradiation. Amorphization of graphite depending upon temperature is discussed. (S.Y.)

Anticipated consumer reaction to irradiated foods

International Nuclear Information System (INIS)

Young, M.

1983-01-01

The reaction on first hearing of food irradiation is horror, revulsion, and disbelief that we could seriously anticipate such a thing. Ignorance coupled with fear of anything to do with the nuclear industry is the reason for such extreme reaction. Before anyone rushes into marketing irradiated foods, a lot of careful preparation must be done. A consumer education program is essential. The consumers must be told why it is proposed to irradiate food, what benefits it will bring to the public. Enough need will have to be demonstrated to overcome the supposed risk factor. Symbol on all irradiated foods must not be used to alert or alarm the consumer but rather as a piece of information. It will be necessary to be ever vigilant, to keep up the diligent training of food irradiators, food handlers and food inspectors. Irradiation is not a substitute for good manufacturing practice. So by using a different name or symbol, irradiated foods will soon be a part of our lives

Onion irradiation - a case study

International Nuclear Information System (INIS)

Huebner, G.

1988-01-01

The irradiation of onions (Allium cepa L.) serves to prevent sprouting associated with long-term storage or transport and storage of onions in climatic conditions which stimulate sprouting. JECFI the Joint Expert Committee for Food Irradiation of FAO/IAEA/WHO, recommended the application of an irradiation dose of up to 150 Gy for sprout inhibition with onions. (author)

Canadian perspectives on food irradiation

International Nuclear Information System (INIS)

Kunstadt, P.

1988-01-01

Canada has been in the forefront of irradiation technology for some 30 years. Nearly 90 of the 140 irradiators used worldwide are Canadian-built, yet Canadian food processors have been very slow to use the technology. The food irradiation regulatory situation in Canada, the factors that influence it, and some significant non-regulatory developments are reviewed. (author)

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

International Nuclear Information System (INIS)

Middleton, E.M.; Teramura, A.H.

1993-01-01

The increasing UV-B radiation (0.28-0.32 μm) 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 (0.32-0.40μm) 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 (> 1300μmol m -2 s -1 ) at two biologically effective daily UV-B irradiances (10.7 and 14.1 kJ m -2 ); UV-A irradiances were matched in Controls (∼5, 9 kJ m -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 2 =0.73, P≤0.001), implying a open-quotes costclose 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

Cherry Irradiation Studies. 1984 annual report

International Nuclear Information System (INIS)

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

1985-04-01

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

Neutron irradiation damage in transition metal carbides

International Nuclear Information System (INIS)

Matsui, Hisayuki; Nesaki, Kouji; Kiritani, Michio

1991-01-01

Effects of neutron irradiation on the physical properties of light transition metal carbides, TiC x , VC x and NbC x , 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 TiC x irradiated with fusion neutrons. Two other carbides (VC x and NbC x ) were irradiated with fission reactor neutrons. The irradiation effects on VC x were not so simple, because of the complex irradiation behavior of 'ordered' phases. For instance, complete disordering was revealed in an ordered phase, 'V 8 C 7 ', after an irradiation dose of 10 25 n/m 2 . (orig.)

Prospects of international trade in irradiated foods

International Nuclear Information System (INIS)

Loaharanu, P.

1990-01-01

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

Effect of gamma irradiation on drugs

International Nuclear Information System (INIS)

Crucq, A.S.; Deridder, V.; Engalytcheff, A.; Slegers, C.; Tilquin, P.

2005-01-01

Several drugs (ceftazidime, vancomycin, glucagon, erythromycin and dobutamine) were studied in order to determine their radiostability. The methods used to measure the degradation of the drug were the potency and the colour change after irradiation. Electron spin resonance (ESR) is currently being used to detect irradiated foodstuffs and may be a promising technique to detect irradiated drugs. Trapped radicals in cefazolin sodium were studied and quantified by ESR for this purpose. It is proposed that the trapped radicals play an important role in the formation of the final radiolytic compounds. The potency of ceftazidime was not significantly modified after an irradiation of 25 kGy, whereas the potency of erythromycin and dobutamine decreased slightly. Glucagon was revealed to be radiosensitive with a significant decrease in its potency after irradiation. The visible spectra of glucagon and dobutamine did not change significantly after irradiation. The absorbance of erythromycin and vancomycin increased after irradiation. According to European Pharmacopoeia standards, the colour change of ceftazidime is unacceptable. The ESR spectra reveal that the trapped radicals in cefazolin sodium are characteristic of an irradiation. The radical concentration is dependent on the irradiation dose and decays over time. Radical concentration in cefazolin sodium was reduced by 99% after 100 days of storage. These radicals are responsible for about 13% of the measured final radiolytic product. Ionic reactions could also lead to final radiolytic products. (author)

International Developments of Food Irradiation

Energy Technology Data Exchange (ETDEWEB)

Loaharanu, P. [Head, Food Preservation Section, Joint FAO/IAEA Division of Nuclear Techniques in Food and Agriculture, Wagramerstr. 5, A-1400, Vienna (Austria)

1997-12-31

Food irradiation is increasingly accepted and applied in many countries in the past decade. Through its use, food losses and food-borne diseases can be reduced significantly, and wider trade in many food items can be facilitated. The past five decades have witnessed a positive evolution on food irradiation according to the following: 1940`s: discovery of principles of food irradiation; 1950`s: initiation of research in advanced countries; 1960`s: research and development were intensified in some advanced and developing countries; 1970`s: proof of wholesomeness of irradiated foods; 1980`s: establishment of national regulations; 1990`s: commercialization and international trade. (Author)

Spices, irradiation and detection methods

International Nuclear Information System (INIS)

Sjoeberg, A.M.; Manninen, M.

1991-01-01

This paper is about microbiological aspects of spices and microbiological methods to detect irradiated food. The proposed method is a combination of the Direct Epifluorescence Filter Technique (DEFT) and the Aerobic Plate Count (APC). The evidence for irradiation of spices is based on the demonstration of a higher DEFT count than the APC. The principle was first tested in our earlier investigation in the detection of irradiation of whole spices. The combined DEFT+APC procedure was found to give a fairly reliable indication of whether or not a whole spice sample had been irradiated. The results are given (8 figs, 22 refs)

Commercial implementation of food irradiation

International Nuclear Information System (INIS)

Welt, M.A.

1985-01-01

Recent positive developments in regulatory matters involving food irradiation appear to be opening the door to commercial implementation of the technology. Experience gained over five years in operating multi-purpose food irradiation facilities in the United States have demonstrated the technical and economic feasibility of the radiation preservation of food for a wide variety of purposes. Public education regarding food irradiation has been intensified especially with the growing favorable involvement of food trade associations, the USDA, and the American Medical Association. After 41 years of development effort, food irradiation will become a commercial reality in 1985. (author)

International Developments of Food Irradiation

Energy Technology Data Exchange (ETDEWEB)

Loaharanu, P [Head, Food Preservation Section, Joint FAO/IAEA Division of Nuclear Techniques in Food and Agriculture, Wagramerstr. 5, A-1400, Vienna (Austria)

1998-12-31

Food irradiation is increasingly accepted and applied in many countries in the past decade. Through its use, food losses and food-borne diseases can be reduced significantly, and wider trade in many food items can be facilitated. The past five decades have witnessed a positive evolution on food irradiation according to the following: 1940`s: discovery of principles of food irradiation; 1950`s: initiation of research in advanced countries; 1960`s: research and development were intensified in some advanced and developing countries; 1970`s: proof of wholesomeness of irradiated foods; 1980`s: establishment of national regulations; 1990`s: commercialization and international trade. (Author)

International Developments of Food Irradiation

International Nuclear Information System (INIS)

Loaharanu, P.

1997-01-01

Food irradiation is increasingly accepted and applied in many countries in the past decade. Through its use, food losses and food-borne diseases can be reduced significantly, and wider trade in many food items can be facilitated. The past five decades have witnessed a positive evolution on food irradiation according to the following: 1940's: discovery of principles of food irradiation; 1950's: initiation of research in advanced countries; 1960's: research and development were intensified in some advanced and developing countries; 1970's: proof of wholesomeness of irradiated foods; 1980's: establishment of national regulations; 1990's: commercialization and international trade. (Author)

Food irradiation control

International Nuclear Information System (INIS)

Ley, F.J.

1988-01-01

A brief review is given of the control and monitoring of food irradiation with particular emphasis on the UK situation. After describing legal aspects, various applications of food irradiation in different countries are listed. Other topics discussed include code of practice for general control for both gamma radiation and electron beam facilities, dose specification, depth dose distribution and dosimetry. (U.K.)

Development of an apparatus for measuring the thermal conductivity of irradiated or non-irradiated graphite; Realisation d'un appareil de mesure de la conductibilite thermique du graphite irradie ou non irradie

Energy Technology Data Exchange (ETDEWEB)

Bocquet, M; Micaud, G

1962-07-01

An apparatus was developed for measuring the thermal conductivity coefficient K of irradiated or non-irradiated graphite. The measurement of K at around room temperature with an accuracy of about 6% is possible. The study specimen is placed in a vacuum between a hot and a cold source which create a temperature gradient {delta}{theta}/ {delta}x in the steady state. The amount of heat transferred, Q, is deduced from the electrical power dissipated at the hot source, after allowing for heat losses. The thermal conductivity coefficient is defined as: K = Q/S. {delta}x/{delta}{theta}, S being the cross section of the sample. Systematic studies have made it possible to determine the mean values of the thermal conductivity. (authors) [French] Un appareil de mesure du coefficient de conductibilite thermique K du graphite irradie ou non irradie a ete realise. Utilisant le principe du transfert de chaleur, il permet de mesurer K au voisinage de la temperature ambiante avec une precision de 6 pour cent environ. L'echantillon de graphite etudie est place sous vide entre une source chaude et une source froide qui creent en regime permanent un gradient de temperature {delta}{theta}/{delta}x La quantite de chaleur transferee Q est deduite de la puissance electrique dissipee dans la source chaude en deduisant les pertes thermiques. Le coefficient de conductibilite thermique est defini par: K = Q/S. {delta}x/{delta}{theta} S designant la section de l'echantillon. Des etudes systematiques ont permis de determiner pour differents graphites non irradies les valeurs moyennes des coefficients de conductibilite thermique. Ces etudes ont mis en evidence pour un type de graphite donne, l'influence de la densite apparente sur le coefficient de conductibilite thermique. A partir de mesures effectuees sur des echantillons de graphite irradies preleves par carottage dans les empilements des reacteurs a moderateur de graphite les variations du rapport K0/Ki en fonction de la dose et de la

Development of data base on food irradiation

International Nuclear Information System (INIS)

Ito, Hitoshi; Kume, Tamikazu; Hashimoto, Shoji; Izumi, Fumio.

1995-12-01

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 institutes relating to this field. For this reason, data base of food irradiation has been completed together with the systems necessary for input the data using computer. In this data base, about 630 data with full reports were inputted in computer in the field of wholesomeness studies, irradiation effects on food, radiation engineering, detection methods of irradiated food and Q and A of food irradiation for easy understanding. Many of these data are inputted by Japanese language. Some English reports on wholesomeness studies are also included which were mainly obtained from international projects of food irradiation. Many of data on food irradiation are responsible in the fields of food science, dietetics, microbiology, radiation biology, molecular biology, medical science, agricultural science, radiation chemistry, radiation engineering and so on. Data base of food irradiation contains many useful data which can apply to many other fields of radiation processing not only on food irradiation but also on sterilization of medical equipments, upgrading of agricultural wastes and others. (author)

Development of data base on food irradiation

Energy Technology Data Exchange (ETDEWEB)

Ito, Hitoshi; Kume, Tamikazu; Hashimoto, Shoji [Japan Atomic Energy Research Inst., Takasaki, Gunma (Japan). Takasaki Radiation Chemistry Research Establishment; Izumi, Fumio

1995-12-01

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 institutes relating to this field. For this reason, data base of food irradiation has been completed together with the systems necessary for input the data using computer. In this data base, about 630 data with full reports were inputted in computer in the field of wholesomeness studies, irradiation effects on food, radiation engineering, detection methods of irradiated food and Q and A of food irradiation for easy understanding. Many of these data are inputted by Japanese language. Some English reports on wholesomeness studies are also included which were mainly obtained from international projects of food irradiation. Many of data on food irradiation are responsible in the fields of food science, dietetics, microbiology, radiation biology, molecular biology, medical science, agricultural science, radiation chemistry, radiation engineering and so on. Data base of food irradiation contains many useful data which can apply to many other fields of radiation processing not only on food irradiation but also on sterilization of medical equipments, upgrading of agricultural wastes and others. (author).

Effect of irradiation on the streptococcus mutans

International Nuclear Information System (INIS)

Ahn, Ki Dong; Kim, Gyu Tae; Choi, Yong Suk; Hwang, Eui Hwan

2007-01-01

To observe direct effect of irradiation on cariogenic Streptococcus mutans. S. mutans GS5 was exposed to irradiation with a single absorbed dose of 10, 20, 30, and 40 Gy. Viability and changes in antibiotic sensitivity, morphology, transcription of virulence factors, and protein profile of bacterium after irradiation were examined by pour plate, disc diffusion method, Transmission electron microscopy. RT-PCR, and SDS-PAGE, respectively. After irradiation with 10 and 20 Gy, viability of S. mutans was reduced. Further increase in irradiation dose, however, did not affect the viability of the remaining cells of S. mutans. Irradiated S. mutans was found to have become sensitive to antibiotics. In particular, the bacterium irradiated with 40 Gy increased its susceptibility to cefotaxime, penicillin, and tetracycline. Under the transmission electron microscope, number of morphologically abnormal cells was increased as the irradiation dose was increased. S. mutans irradiated with 10 Gy revealed a change in the cell wall and cell membrane. As irradiation dose was increased. a higher number of cells showed thickened cell wall and cell membrane and lysis, and appearance of ghost cells was noticeable. In RT-PCR, no difference was detected in expression of gtfB and spaP between cells with and without irradiation of 40 Gy. In SDS-PAGE, proteins with higher molecular masses were gradually diminished as irradiation dose was increased. These results suggest that irradiation affects the cell integrity of S. mutans, as observed by SDS-PAGE, and as manifested by the change in cell morphology, antibiotic sensitivity, and eventually viability of the bacterium

Effect of irradiation on the streptococcus mutans

Energy Technology Data Exchange (ETDEWEB)

Ahn, Ki Dong; Kim, Gyu Tae; Choi, Yong Suk; Hwang, Eui Hwan [Kyung Hee Univ., Seoul (Korea, Republic of)

2007-03-15

To observe direct effect of irradiation on cariogenic Streptococcus mutans. S. mutans GS5 was exposed to irradiation with a single absorbed dose of 10, 20, 30, and 40 Gy. Viability and changes in antibiotic sensitivity, morphology, transcription of virulence factors, and protein profile of bacterium after irradiation were examined by pour plate, disc diffusion method, Transmission electron microscopy. RT-PCR, and SDS-PAGE, respectively. After irradiation with 10 and 20 Gy, viability of S. mutans was reduced. Further increase in irradiation dose, however, did not affect the viability of the remaining cells of S. mutans. Irradiated S. mutans was found to have become sensitive to antibiotics. In particular, the bacterium irradiated with 40 Gy increased its susceptibility to cefotaxime, penicillin, and tetracycline. Under the transmission electron microscope, number of morphologically abnormal cells was increased as the irradiation dose was increased. S. mutans irradiated with 10 Gy revealed a change in the cell wall and cell membrane. As irradiation dose was increased. a higher number of cells showed thickened cell wall and cell membrane and lysis, and appearance of ghost cells was noticeable. In RT-PCR, no difference was detected in expression of gtfB and spaP between cells with and without irradiation of 40 Gy. In SDS-PAGE, proteins with higher molecular masses were gradually diminished as irradiation dose was increased. These results suggest that irradiation affects the cell integrity of S. mutans, as observed by SDS-PAGE, and as manifested by the change in cell morphology, antibiotic sensitivity, and eventually viability of the bacterium.

Basic design requirements for indigenous irradiator

International Nuclear Information System (INIS)

Anwar Abd Rahman; Rosli Darmawan; Mohd Arif Hamzah; Fadil Ismail; Muhd Nor Atan

2007-01-01

Most of the irradiators owned by Nuclear Malaysia are imported from other countries. The irradiators are used for various applications such as Research and Development, agriculture and industry. There is a plan to develop locally made multi-purpose gamma irradiator in 9th Malaysia Plan which equipped with better safety features. This paper will discuss the basic requirements for the design of the irradiator. (Author)

Histochemical differentiation between unirradiated and gamma-irradiated tissue in commercial use of some irradiated vegetables

International Nuclear Information System (INIS)

Foa, E.

1978-01-01

The use of gamma irradiation as a commercial method for the preservation of fruits and vegetables calls for methods of differentiation between unirradiated and irradiated products. A new approach to studying the influence of gamma irradiation on vegetable tissue at the cellular level by histochemical techniques has been developed by the authors and already applied to a number of fruits and vegetables. The possibility of evidencing radiation effects in the polysaccharide components of the cell wall suggested that these detected differences could be applied to differentiate irradiated from unirradiated tomatoes and potatoes. Some work done to determine changes in the cell wall polysaccharides of gamma-irradiated potatoes and tomatoes and to relate these changes to some other factors, such as storage time and vegetable variety, is reported here. While significant differences have been found in the optical densities of the total polysaccharides of the cell wall as a function of irradiation and of the other variables mentioned, it is not yet possible to use these values as a means of reliable differentiation. (author)

Selection of irradiator for potato preservation

Energy Technology Data Exchange (ETDEWEB)

Kinsara, A R; Melaibari, A G; Abulfaraj, W H; Mamoon, A M; Kamal, S E [Nuclear Engineering Department, Faculty of Engineering, King Abdulaziz University P.O.Box 9027, Jeddah-21413, (Saudi Arabia)

1997-12-31

A formal decision methodology is a sound approach for assisting in decision making needed for the selection of irradiators for Potato preservation. A formal analysis is preferred over an informal intuitive analysis which has limitations. This will focus on substantial issues and provide the basis for a compromise between conflicting objectives. All critical issues in selection of irradiators for Potato preservation can be addressed within the decision analysis framework. Of special significance is the treatment of the uncertainly associated with consequences of a decision and the preferences of the experts. A decision theory is employed in providing a strategy for implementation of the irradiator selection for food preservation for Saudi Arabia. To select a suitable decision methodology for the present case, a detailed survey of available decision methods was conducted. These methods have been developed and applied with varying degrees of success to many diverse areas of interest. Based on detailed surveys, the Analytic Hierarchy process (AHP) was selected to evaluate the various irradiators for Potato irradiation. These are electron accelerators, X-ray irradiators, and gamma irradiators. The purpose was to determine the optimal. The set of factors impacting irradiator selection were developed and defined to provide comprehensive and realistic variables that judge the represented irradiator alternatives. The factors developed are economic considerations, technical considerations, safety aspects, and compatibility with local environment. The AHP computer program was developed to computerize the tedious complicated computations towards implementing the AHP systematic procedures to solve the present problem. The program was developed using FOXPRO. Based upon the available data, and employing the APH computer program, the results show superiority of {sup 60} Co gamma-ray irradiator over other irradiators for saudi arabia`s present circumstances. 2 figs.,7 tabs.

HANARO fuel irradiation test (II): revision

Energy Technology Data Exchange (ETDEWEB)

Sohn, D. S.; Kim, H.; Chae, H. T.; Lee, C. S.; Kim, B. G.; Lee, C. B

2001-04-01

In order to fulfill the requirement to prove HANARO fuel integrity when irradiated at a power greater than 112.8 kW/m, which was imposed during HANARO licensing, and to verify the irradiation performance of HANARO fuel, the in-pile irradiation test of HANARO fuel has been performed. Two types of test fuel, the un-instrumented Type A fuel for higher burnup irradiation in shorter period than the driver fuel and the instrumented Type B fuel for higher linear heat rate and precise measurement of irradiation conditions, have been designed and fabricated. The test fuel assemblies were irradiated in HANARO. The two Type A fuel assemblies were intended to be irradiated to medium and high burnup and have been discharged after 69.9 at% and 85.5 at% peak burnup, respectively. Type B fuel assembly was intended to be irradiated at high power with different instrumentations and achieved a maximum power higher than 120 kW/m without losing its integrity and without showing any irregular behavior. The Type A fuel assemblies were cooled for about 6 months and transported to the IMEF(Irradiated Material Examination Facility) for consequent evaluation. Detailed non-destructive and destructive PIE (Post-Irradiation Examination), such as the measurement of burnup distribution, fuel swelling, clad corrosion, dimensional changes, fuel rod bending strength, micro-structure, etc., has been performed. The measured results have been analysed/compared with the predicted performance values and the design criteria. It has been verified that HANARO fuel maintains proper in-pile performance and integrity even at the high power of 120 kw/m up to the high burnup of 85 at%. This report is the revision of KAERI/TR-1816/2001 on the irradiation test for HANARO fuel.

Irradiation as a quarantine treatment

International Nuclear Information System (INIS)

Burditt, A.K. Jr.

1991-01-01

The use of irradiation as an alternative treatment for commodities subject to infestation by pests of quarantine importance is outlined in this article. A dose of 300 Gy or less has been found to prevent adult emergence when insect eggs or larvae are irradiated and research has shown that such doses will not affect the quality of most commodities. The use of gamma rays from cobalt-60 or caesium-137 sources, as well as electrons or X-rays from linear accelerators, has been approved for food irradiation. Irradiation facilities must meet regulations promulgated by nuclear, health and agricultural quarantine agencies with regard to location, facility design, sources, operation, personnel, dosimetry and other requirements. Education of industry operators and the general public is needed in order to gain acceptance of irradiation as a quarantine treatment. (author). 21 refs, 1 tab

Food irradiation receives international acceptance

Energy Technology Data Exchange (ETDEWEB)

Beddoes, J M [Atomic Energy of Canada Ltd., Ottawa, Ontario. Commercial Products

1982-04-01

Irradiation has advantages as a method of preserving food, especially in the Third World. The author tabulates some examples of actual use of food irradiation with dates and tonnages, and tells the story of the gradual acceptance of food irradiation by the World Health Organization, other international bodies, and the U.S. Food and Drug Administration (USFDA). At present, the joint IAEA/FAO/WHO standard permits an energy level of up to 5 MeV for gamma rays, well above the 1.3 MeV energy level of /sup 60/Co. The USFDA permits irradiation of any food up to 10 krad, and minor constituents of a diet may be irradiated up to 5 Mrad. The final hurdle to be cleared, that of economic acceptance, depends on convincing the food processing industry that the process is technically and economically efficient.

Irradiation Behavior and Post-Irradiation Examinations of an Acoustic Sensor Using a Piezoelectric Transducer

International Nuclear Information System (INIS)

Lambert, T.; Zacharie-Aubrun, I.; Hanifi, K.; Valot, Ch.; Fayette, L.; Rosenkantz, E.; Ferrandis, J.Y.; Tiratay, X.

2013-06-01

The development of advanced instrumentation for in-pile experiments in Material Testing Reactor constitutes a main goal for the improvement of the nuclear fuel behavior knowledge. In the framework of high burn-up fuel experiments under transient operating conditions, an innovative sensor based on acoustic method was developed by CEA and IES (Southern Electronic Institute).This sensor is used to determine the on-line composition of the gases located in fuel rodlet free volume and thus, allows calculating the molar fractions of fission gases and helium. The main principle of the composition determination by acoustic method consists in measuring the time of flight of an acoustic signal emitted and reflected in a specific cavity. A piezoelectric transducer, driven by a pulse generator, generates the acoustic wave in the cavity. The piezoelectric transducer is a PZT ceramic disk, mainly consisting of lead, zirconium and titanium. This acoustic method was tested with success during a first experiment called REMORA 3, and the results were used to differentiate helium and fission gas release kinetics under transient operating conditions. However, during the irradiation test, acoustic signal degradation was observed, mainly due to irradiation effect but also due to the increasing of the gas temperature. Despite this acoustic signal degradation, the time of flight measurements were carried out with good accuracy throughout the test, thanks to the development of a more efficient signal processing. After experiment, neutronic calculations were performed in order to determine neutron fluence at the level of the piezoelectric transducer. In order to have a better understanding of the acoustic sensor behavior under irradiation, Post Irradiation Examination program was done on piezoelectric transducer and on acoustic coupling material too. These examinations were also realized on a non-irradiated acoustic sensor built in the same conditions and with the same materials and the same

Food irradiation and its biological effects

International Nuclear Information System (INIS)

Shah, Alok; Nanjappa, C.; Chauhan, O.P.

2014-01-01

Irradiation of foods drew attention mostly in 1960s for disinfestation of food grains, spices and sprout inhibition in mainly potato and onion. γ-irradiation at 0.25 to 1 kGy dosage levels are usually used for irradiating grains, legumes, spices and sprout-prone vegetables. Irradiation of foods with in permissible dosage levels of 0.25 to 5 kGy is usually considered fairly safe from human consumption point of view not withstanding usual health concerns about its usage in foods. Irradiation of foods, in mostly solid or semi-solid form, at 5 kGy levels of γ-irradiation can achieve radicidation or, radiation equivalent of pasteurization and, if γ-irradiation is used at 10 kGy, it can achieve radappertization or, radiation equivalent of thermal commercial sterilization. However, the food industry uses γ-irradiation at 0.25 to 2 kGy only for mostly disinfestation of food grains/legumes, spices, sprout inhibition in potato and onion and, for surface sanitation of frozen fish, poultry and meat. Exposure to irradiation creates free radicals in foods that are capable of destroying some of the spoilage and pathogenic microflora but the same can also damage vitamins and enzymes besides creating some new harmful new chemical species, called unique radiolytic products (URPs), by combining with certain chemicals that a food may be laced with (like pesticides/fungicides). Exposure to high-energy electron beams are also known to create deleterious biological effects which may even lead to detection of trace amounts of radioactivity in the food. Some possible causes delineated for such harmful biological effects of irradiation include: irradiation induced vitamin deficiencies, the inactivity of enzymes in the foods, DNA damage and toxic radiolytic products in the foods. Irradiation, a non-thermal food preservation technique, has a role in salvaging enormous post harvest losses (25-30%) in developing economies to increase the per capita availability of foods. (author)

Economics of food irradiation

International Nuclear Information System (INIS)

Deitch, J.

1982-01-01

This article examines the cost competitiveness of the food irradiation process. An analysis of the principal factors--the product, physical plant, irradiation source, and financing--that impact on cost is made. Equations are developed and used to calculate the size of the source for planned product throughput, efficiency factors, power requirements, and operating costs of sources, radionuclides, and accelerators. Methods of financing and capital investment are discussed. A series of tables show cost breakdowns of sources, buildings, equipment, and essential support facilities for both a cobalt-60 and a 10-MeV electron accelerator facility. Additional tables present irradiation costs as functions of a number of parameters--power input, source size, dose, and hours of annual operation. The use of the numbers in the tables are explained by examples of calculations of the irradiation costs for disinfestation of grains and radicidation of feed

Packing for food irradiation

Energy Technology Data Exchange (ETDEWEB)

Chmielewski, A G [Institute of Nuclear Chemistry and Technology, Warsaw (Poland)

2006-07-01

Joint FAO/IAEA/WHO Expert Committee approved the use of radiation treatment of foods. Nowadays food packaging are mostly made of plastics, natural or synthetic, therefore effect of irradiation on these materials is crucial for packing engineering for food irradiation technology. By selecting the right polymer materials for food packaging it can be ensured that the critical elements of material and product performance are not compromised. When packaging materials are in contact with food at the time of irradiation that regulatory approvals sometimes apply. The review of the R-and-D and technical papers regarding material selection, testing and approval is presented in the report. The most information come from the USA where this subject is well elaborated, the International Atomic Energy Agency (IAEA) reports are reviewed as well. The report can be useful for scientists and food irradiation plants operators. (author)

Packing for food irradiation

International Nuclear Information System (INIS)

Chmielewski, A.G.

2006-01-01

Joint FAO/IAEA/WHO Expert Committee approved the use of radiation treatment of foods. Nowadays food packaging are mostly made of plastics, natural or synthetic, therefore effect of irradiation on these materials is crucial for packing engineering for food irradiation technology. By selecting the right polymer materials for food packaging it can be ensured that the critical elements of material and product performance are not compromised. When packaging materials are in contact with food at the time of irradiation that regulatory approvals sometimes apply. The review of the R-and-D and technical papers regarding material selection, testing and approval is presented in the report. The most information come from the USA where this subject is well elaborated, the International Atomic Energy Agency (IAEA) reports are reviewed as well. The report can be useful for scientists and food irradiation plants operators. (author)

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

Science.gov (United States)

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

2013-11-01

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

Irradiation Creep of Ferritic-Martensitic Steels EP-450, EP-823 and EI-852 Irradiated in the BN-350 Reactor over Wide Ranges of Irradiation Temperature and Dose

International Nuclear Information System (INIS)

Porollo, S.I.; Konobeev, Y.V.; Ivanov, A.A.; Shulepin, S.V.; Garner, F.

2007-01-01

Full text of publication follows: Ferritic/martensitic (F/M) steels appear to be the most promising materials for advanced nuclear systems, especially for fusion reactors. Their main advantages are higher resistance to swelling and lower irradiation creep rate as has been repeatedly demonstrated in examinations of these materials after irradiation. Nevertheless, available experimental data on irradiation resistance of F/M steels are insufficient, with the greatest deficiency of data for high doses and for both low and high irradiation temperatures. From the very beginning of operation the BN-350 fast reactor has been used for irradiation of specimens of structural materials, including F/M steels. The most unique feature of BN-350 was its low inlet sodium temperature, allowing irradiation at temperatures over a very wide range of temperatures compared with the range in other fast reactors. In this paper data are presented on swelling and irradiation creep of three Russian F/M steels EP-450, EP-823 and EI-852, irradiated in experimental assemblies of the BN-350 reactor at temperatures in the range of 305-700 deg. C to doses ranging from 20 to 89 dpa. The investigation was performed using gas-pressurized creep tubes with hoop stresses in the range of 0 - 294 MPa. (authors)

Pollen-gamma irradiation on pineapple and pollination using irradiated pollen

International Nuclear Information System (INIS)

Benega, R.; Cisneros, A.; Martinez, J.; Arias, E.; Yabor, L.; Isidron, M.; Castillo, E.; Fernandez, J.