Irradiation monitoring of spices by chemiluminescence method

International Nuclear Information System (INIS)

Bhatti, K.A.; Khan, H.M.; Sattar, A.; Ahmad, A.

2001-01-01

Some spices (cumin, coriander, black pepper and red pepper), commonly used due to their specific aroma and nutritional value were studied using chemiluminescence (CL) method to test whether the food has been irradiated or not. The spices were ground to different mesh sizes and subjected to gamma ray doses of 2.5, 5.0, 7.5 and 10 Kgy. The effect of radiation doses and particle size on the CL response of irradiated and un-irradiated samples was checked using luminol and lucigenin sensitizers. The storage experiment was also performed for all spices with both the sensitizers in order to pick the suitable sensitizer for CL study. During this study Co-60 gamma ray source and Bio-orbit 1250 luminometer were used after precise calibration

Meso-scale magnetic signatures for nuclear reactor steel irradiation embrittlement monitoring

Energy Technology Data Exchange (ETDEWEB)

Suter, J. D., E-mail: pradeep.ramuhalli@pnnl.gov; Ramuhalli, P., E-mail: pradeep.ramuhalli@pnnl.gov; Hu, S.; Li, Y.; Jiang, W.; Edwards, D. J.; Schemer-Kohrn, A. L.; Johnson, B. R. [Pacific Northwest National Laboratory, 902 Battelle Blvd, Richland, WA 99352 (United States); McCloy, J. S., E-mail: john.mccloy@wsu.edu; Xu, K., E-mail: john.mccloy@wsu.edu [Washington State University, PO Box 642920, Pullman, WA 99164 (United States)

2015-03-31

Verifying the structural integrity of passive components in light water and advanced reactors will be necessary to ensure safe, long-term operations of the existing U.S. nuclear fleet. This objective can be achieved through nondestructive condition monitoring techniques, which can be integrated with plant operations to quantify the “state of health” of structural materials in real-time. While nondestructive methods for monitoring many classes of degradation (such as fatigue or stress corrosion cracking) are relatively advanced, this is not the case for degradation caused by irradiation. The development of nondestructive evaluation technologies for these types of degradation will require advanced materials characterization techniques and tools that enable comprehensive understanding of nuclear reactor material microstructural and behavioral changes under extreme operating environments. Irradiation-induced degradation of reactor steels causes changes in their microstructure that impacts their micro-magnetic properties. In this paper, we describe preliminary results of integrating advanced material characterization techniques with meso-scale computational models. In the future, this will help to provide an interpretive understanding of the state of degradation in structural materials. Microstructural data are presented from monocrystalline Fe and are correlated with variable-field magnetic force microscopy and micro-magnetic measurements. Ongoing research is focused on extending the measurements and models on thin films to gain insights into the structural state of irradiated materials and the resulting impact on magnetic properties. Preliminary conclusions from these correlations are presented, and next steps described.

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.

Method for monitoring irradiated nuclear fuel using cerenkov radiation

International Nuclear Information System (INIS)

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

1983-01-01

A method is provided for monitoring irradiated nuclear fuel inventories located in a water-filled storage pond wherein the intensity of the cerenkov radiation emitted from the water in the vicinity of the nuclear fuel is measured. This intensity is then compared with the expected intensity for nuclear fuel having a corresponding degree of irradiation exposure and time period after removal from a reactor core. Where the nuclear fuel inventory is located in an assembly having fuel pins or rods with intervening voids, the cerenkov light intensity measurement is taken at selected bright spots corresponding to the water-filled interstices of the assembly in the water storage, the waterfilled interstices acting as cerenkov light channels so as to reduce cross-talk. On-line digital analysis of an analog video signal is possible, or video tapes may be used for later measurement using a video editor and an electrometer. Direct measurement of the cerenkov radiation intensity also is possible using spot photometers pointed at the assembly

Neutron monitoring measurements for the CIT [Compact Ignition Tokamak] materials irradiations in the ATR I1 position

International Nuclear Information System (INIS)

Rogers, J.W.; Anderl, R.A.

1989-12-01

Measurements were performed to help characterize the neutron environments in which the Compact Ignition Tokamak (CIT) materials were irradiated. These materials were irradiated in a lead shield plug assembly at the ATR I1 position. Neutron monitor materials were placed in the capsules in proximity with the CIT specimens. The neutron monitors sensed the neutrons through reactions that have different neutron energy region responses. By measuring the radioactivity of the neutron monitors it was possible to determine the neutron fluence rates (n/cm 2 /sec) and fluences (n/cm 2 ) at the locations of the monitors. It was also possible to determine the axial and radial gradients of the neutron environments near the specimens. This report presents the results obtained from these measurements for both the CIT number-sign 1 (ORNL 64-2) and CIT number-sign 2 (ORNL 64-1) capsules. In general, ASTM methods and procedures were used in all neutron monitoring associated activities. 7 refs., 9 figs., 10 tabs

Development of absolute intensity monitors and homogeneous irradiation system for synchrotron radiation at SPring-8

International Nuclear Information System (INIS)

Nariyama, N.; Taniguchi, S.; Kishi, N.; Ohnishi, S.; Odano, N.

2003-01-01

At SPring-8 of 8-GeV synchrotron radiation facility in Japan, high-intense monoenergetic photon beam up to hundred keV are available. For biological and medical researches, the absolute intensity monitor and homogeneous irradiation system are necessary. In this study, as intensity monitor two sizes of parallel-plate free-air ionization chambers were developed: plate distance of 8.5 cm for high-energy photons up to 190 keV and that of 0.42 cm for low-energy high-intense photons from undulator. Sizes of the larger chamber were determined considering electron loss using a Monte Carlo electron-photon transport code EGS4. For homogeneous irradiation method, a rotational linear-scanning method was proposed. An experiment was carried out at bending-magnet beamlines BL20B2 and 38B1 for high-energy photons. Dose measured with the chamber was compared to that of another free-air ionization chamber with 5-cm plate separation and a Si-PIN photodiode, which have been calibrated with a calorimeter. Agreement was confirmed from 30 keV up to 150 keV with a discrepancy less than 3%, which were independent of the beam size, intensity and injection position of the chamber. For intense photons from undulator, saturation measurement was made using the smaller chamber at BL46XU. Saturation was confirmed at 3 kV for 15- and 20-keV photons up to 10 12 photons/s. Using the larger chamber, fixed and Xθ -scanning irradiation methods were compared by irradiating thermoluminescent dosimeters at BL20B2, which can provide broad beam. As a function of the estimated exposure, all the signal data points became on the same straight line. Consequently, the Xθ -scanning method was found to be effective

Assessment of necessary regularity of internal irradiation monitoring on the basis of direct and indirect methods of dosimetry

International Nuclear Information System (INIS)

Malykhin, V.M.; Ivanova, N.I.

1981-01-01

It is shown that when assessing the necessary periodicity of internal irradiation monitoring, it is required to take account of the nature (rhythm) of radionuclide intake to the organism during the monitoring period, the effective period of radionuclide biological half-life, its activity in the organism, sensitivity of the technique applied and the labour-consumig character of the monitoring method [ru

Study of TileCal scintillator irradiation using the minimum bias integrators

CERN Document Server

AUTHOR|(INSPIRE)INSPIRE-00387867; The ATLAS collaboration

2016-01-01

The Tile Calorimeter (TileCal) is the central hadronic calorimeter of the ATLAS experiment at the LHC. It provides precise energy measurements of hadrons, jets, taus and missing transverse energy. The monitoring and calibration of the calorimeter response at each stage of the signal development is done by a movable $^{137}$Cs radioactive source, a laser calibration system and a charge injection system. Moreover, during LHC data taking, an integrator-based readout provides the signals coming from inelastic proton-proton collisions at predominantly low momentum transfer (minimum bias events) and allows monitoring of the instantaneous ATLAS luminosity as well as the response of calorimeter cells. The integrator currents have been used to detect and quantify the effect of TileCal scintillator irradiation using the data taken in 2012 and 2015 that correspond to about 22 fb$^{−1}$ and 4 fb$^{−1}$ of integrated luminosity, respectively. Finally, the response variation for an irradiated cell has been studied comb...

Effects of synchronous irradiance monitoring and correction of current-voltage curves on the outdoor performance measurements of photovoltaic modules

Science.gov (United States)

Hishikawa, Yoshihiro; Doi, Takuya; Higa, Michiya; Ohshima, Hironori; Takenouchi, Takakazu; Yamagoe, Kengo

2017-08-01

Precise outdoor measurement of the current-voltage (I-V) curves of photovoltaic (PV) modules is desired for many applications such as low-cost onsite performance measurement, monitoring, and diagnosis. Conventional outdoor measurement technologies have a problem in that their precision is low when the solar irradiance is unstable, hence, limiting the opportunity of precise measurement only on clear sunny days. The purpose of this study is to investigate an outdoor measurement procedure, that can improve both the measurement opportunity and precision. Fast I-V curve measurements within 0.2 s and synchronous measurement of irradiance using a PV module irradiance sensor very effectively improved the precision. A small standard deviation (σ) of the module’s maximum output power (P max) in the range of 0.7-0.9% is demonstrated, based on the basis of a 6 month experiment, that mainly includes partly sunny days and cloudy days, during which the solar irradiance is unstable. The σ was further improved to 0.3-0.5% by correcting the curves for the small variation of irradiance. This indicates that the procedure of this study enables much more reproducible I-V curve measurements than a conventional usual procedure under various climatic conditions. Factors that affect measurement results are discussed, to further improve the precision.

Irradiation capsule design capable of continuously monitoring the creepdown of Zircaloy fuel cladding

International Nuclear Information System (INIS)

Thoms, K.R.; Dodd, C.V.; van der Kaa, T.; Hobson, D.O.

1978-01-01

An irradiation capsule which permits continuous monitoring of the creepdown of Zircaloy tubing has been designed and given preliminary tests. This design effort is the major element of a cooperative research program between the United States Nuclear Regulatory Commission and the Netherlands Energy Research Foundation (ECN) and is a part of the NRC-sponsored Zircaloy creepdown program. The purpose of the Zircaloy creepdown program is to provide data on the deformation characteristics of Zircaloy tubes, typical of LWR fuel element cladding, under combined axial and tangential compressive stresses. These data will be used to verify and improve the material behavior codes that are used for the description of fuel pin behavior. The first capsule of this series contains a mockup test specimen which was machined with three different diameters, nominally 10.92-mm, 10.54-mm and 11.30-mm (.430-in., .415-in., and .445-in.). This test specimen can be moved axially thereby varying the lift-off and serving as a calibration device for the eddy-current deformation monitoring probes. Fabrication of this capsule has been completed and during out-or-reactor checkout we were able to obtain a resolution of better than 0.01-mm (0.0004-in.). The capsule is scheduled for installation in the HFR on February 8, 1978, for a 26 day irradiation test. The first pressurized capsule, and therefore the first one to monitor in-reactor cladding deformation, will be installed in the HFR on May 3, 1978

Determination of cross sections of nuclear reactions to use Al as monitoring foil in heavy ion irradiation with 20Ne projectile

International Nuclear Information System (INIS)

Chowdhury, D.P.; Datta, J.; Guin, R.; Verma, R.

2009-01-01

The beam current is generally accurately measured using monitoring foils during the irradiation of thick samples by high energy ion beams. The cross sections of many nuclear reactions induced by light particles are available in literature for use as monitoring foil. However, such cross sections of heavy ion induced reactions are not reported much for their use in applied works. We have determined cross sections of two nuclear reactions, 27 Al ( 20 Ne,2p2n) 43 Sc and 27 Al ( 20 Ne, 2pn) 44m Sc, to use Al as monitoring foil for the irradiation with 20 Ne heavy ion beam. (author)

Positron lifetime studies of electron irradiated copper

International Nuclear Information System (INIS)

Hadnagy, T.D.

1976-01-01

Single-crystal copper was irradiated with 4.5-MeV electrons producing simple Frenkel defects as well as a significant concentration of divacancies. Mean positron lifetime characteristics, which are sensitive to the presence of vacancies and multivacancies in copper, was monitored after isochronal anneals between 80 and 800 0 K to determine the relative change of characteristic mean lifetimes and their associated intensities. Also a study of the dependence of the mean positron lifetime on the total electron fluence was made and compared with existing theories relating these lifetimes to vacancy or multivacancy concentrations. Numerical data from curve fitting procedures using a conventional trapping model for defect-induced changes in positron lifetimes indicate that upon irradiation with 4.5-MeV electrons at 80 0 K, about 8 percent of the defects produced are divacancy units. Divacancy units appear to be several times more effective in trapping positrons than are monovacancies. Further, the experimental data suggest that the stage III annealing processes in electron-irradiated copper most probably involve the motion and removal of both monovacancies and divacancies. A conglomerate (multivacancy) unit appears to exist as a stable entity even after annealing procedures are carried out at temperatures slightly above the stage III region. Such a stable unit could serve as a nucleation center for the appearance of voids

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

Kinetics of the radicals induced in gamma irradiated sulfafurazole: an EPR study

International Nuclear Information System (INIS)

Colak, S.; Korkmaz, M.

2004-01-01

The spectroscopic and kinetic features of the radiolytic intermediates produced in gamma irradiated sulfafurazole (SFZ) were investigated at different temperatures in the dose range 5-50 kGy using EPR and IR techniques. The imodiation produced two species (A, B) in SFZ. The heights of the peaks were used to monitor the temperature, time dependent and kinetic features of the radical species contributing to the EPR spectrum. The applicability of EPR technique for monitoring radiosterilization of SFZ is discussed. The radiation yield of solid SFZ was found to be very low (G=0.16), and basing on this it was concluded that SFZ and SFZ containing drugs can be safely sterilized by radiation. The EPR data were used to characterize the contributing radicals produced in gamma irradiated SFZ. No definite difference was observed between unirradiated and irradiated IR spectra of SFZ. (orig.)

Towards a Unified Environmental Monitoring, Control and Data Management System for Irradiation Facilities: the CERN IRRAD Use Case

CERN Document Server

Gkotse, Blerina; Jouvelot, Pierre; Matli, Emanuele; Pezzullo, Giuseppe; Ravotti, Federico

2017-01-01

The qualification of materials, electronic components and equipment for the CERN High Energy Physics experiments and beyond requires testing against possible radiation effects. These quite complex tests are performed by specialized teams working in irradiation facilities such as IRRAD, the Proton Irradiation Facility at CERN. Building upon the details of the overall irradiation control, monitoring, and logistical systems of IRRAD as a use case, we introduce the motivations for and general architecture of its new data management framework, currently under development at CERN. This infrastructure is intended to allow for the seamless and comprehensive handling of IRRAD irradiation experiments and to help manage all aspects of the facility. Its architecture, currently focused on the specific requirements of the IRRAD facility, is intended to be upgraded to a general framework that could be used in other irradiation facilities within the radiation effects community, as well as for other applications.

An irradiation facility with a horizontal beam for radiobiological studies

International Nuclear Information System (INIS)

Czub, J.; Adamus, T.; Banas, D.

2006-01-01

A facility with a horizontal beam for radiobiological experiments with heavy ions has been designed and constructed at the Heavy Ion Laboratory in Warsaw University. The facility is optimal to investigate the radiobiological effects of charged heavy particles on a cellular or molecular level as the plateau of the Bragg curve as well as in the Bragg peak. The passive beam spread out by a thin scattering foil provides a homogeneous irradiation field over an area of at least 1 x 1 cm 2 . For in vitro irradiation of biological samples the passive beam spreading combined with the x - y mechanical scanning of the irradiated sample was found to be an optimum solution. Using x - y step motor, the homogenous beam of ions with the energy loss range in the cells varied from 1 MeV/μm to 200 keV/μm is able to cover a 6 cm in diameter Petri dish that holds the biological samples. Moreover on-line fluence monitoring based on single-particle counting is performed to determine the dose absorbed by cells. Data acquisition system for dosimetry and ion monitoring based on a personal computer is described. (author)

Monitoring free radicals in γ-irradiated food

International Nuclear Information System (INIS)

Hunter, C.R.; Hutton, D.R.

1988-01-01

Irradiation of various food products, including vegetables, fruits, meats, seafoods, herbs, spices and seeds by appropriate doses by γ rays has for many years been suggested as a means of killing bacteria, viruses and pests and so preserving the foods. The position of food irradiation is under review in Australia through consumer organisations (Australian Consumers Association 1987) and by a current Federal Government inquiry. From these reviews and inquiries recommendations for irradiation, packaging, etc., are emerging, with for example, recommended maximum dose of 10 kGy for Australia, with 6 kGy being a minimum dose for grains and spices

XRD monitoring of α self-irradiation in uranium-americium mixed oxides.

Science.gov (United States)

Horlait, Denis; Lebreton, Florent; Roussel, Pascal; Delahaye, Thibaud

2013-12-16

The structural evolution under (241)Am self-irradiation of U(1-x)Am(x)O(2±δ) transmutation fuels (with x ≤ 0.5) was studied by X-ray diffraction (XRD). Samples first underwent a preliminary heat treatment performed under a reducing atmosphere (Ar/H2(4%)) aiming to recover the previously accumulated structural defects. Over all measurements (carried out over up to a full year and for integrated doses up to 1.5 × 10(18) α-decay events·g(-1)), only fluorite U(1-x)Am(x)O(2±δ) solid solutions were observed. Within a few days after the end of the heat treatment, each of the five studied samples was slowly oxidized as a consequence of their move to air atmosphere, which is evidenced by XRD by an initial sharp decrease of the unit cell parameter. For the compounds with x ≤ 0.15, this oxidation occurred without any phase transitions, but for U0.6Am0.4O(2±δ) and U0.5Am0.5O(2±δ), this process is accompanied by a transition from a first fluorite solid solution to a second oxidized one, as the latter is thermodynamically stable in ambient conditions. In the meantime and after the oxidation process, (241)Am α self-irradiation caused a structural swelling up to ∼0.8 vol %, independently of the sample composition. The kinetic constants of swelling were also determined by regression of experimental data and are, as expected, dependent on x and thus on the dose rate. The normalization of these kinetic constants by sample α-activity, however, leads to very close swelling rates among the samples. Finally, evolutions of microstrain and crystallite size were also monitored, but for the considered dose rates and cumulated doses, α self-irradiation was found, within the limits of the diffractometer used, to have almost no impact on these characteristics. Microstrain was found to be influenced instead by the americium content in the materials (i.e., by the impurities associated with americium starting material and the increase of cationic charge heterogeneity with

Effect of irradiation on functional properties of Gum Tragacanth

Directory of Open Access Journals (Sweden)

Neda Mollakhalili meybodi

2017-03-01

Full Text Available Background and objective: irradiation is a physical treatment in which products are exposed to ionized radiation such as gamma and x rays to improve the security and quality. Hydrocolloids are components that are used in food science to improve texture properties. Exposing to irradiation treatment may change structural and functional properties. By regard to the importance of irradiation on decontaminating of hydrocolloids in food application, the aim of this study is studying the effect of irradiation at different doses on functional properties of Gum Tragacanth in food application. Material and methods: effect of irradiation treatment was studied on the rheological properties, zeta potential, particle size distribution and surface tension of dispersion systems contained 0/5% w/ w gum tragacanth that is irradiated at different doses (0, 0.75. 3, 5 kGy. The effect of irradiation on rheological properties was monitored by rheometer. In order to monitor the effect of irradiation treatment on particle size distribution, zeta potential and surface tension, particle sizer, Brookhaven zeta plus and tensiometer sere used respectively. All treatments were performed three times and the data were analyzed by one way ANOVA. Significant differences between means were identified (P values < 0.05 using Duncan test. Results: Irradiation, change rheologiacal properties and particle size distribution of dispersion contained gum tragacanth. Irradiation treatment up to 0.75 kGy increase zeta potential, but irradiating at higher doses decrease it again. Results of studying parameters showed that irradiation changes the functional properties by affecting on structure. These changes depend on irradiation dose Conclusion: Gum tragacanth irradiation may improve the functional properties by affecting on structure.

Infrared absorption studies of the annealing of irradiated diamonds

International Nuclear Information System (INIS)

Woods, G.S.

1984-01-01

Natural (types Ia and IIa) and synthetic (type Ib) diamonds have been irradiated with energetic electrons and neutrons and then heated at temperatures up to 1400 deg C. Attendant changes in the infrared absorption spectra, especially above the Raman frequency (1332 cm -1 ), have been monitored. The most prominent absorption to develop in the infrared region proper, on annealing both type Ia and type Ib specimens, whether electron- or neutron-irradiated is the H1a line at 1450 cm -1 . Measurements taken of neutron-irradiated type Ia specimens show that the strength of this line is specimen-dependent, and that it is a linear function of radiation dose. Isochronal annealing studies show that the onset of the line occurs during heating at 250 deg C for type Ia specimens and at 650 deg C for type Ib specimens. The absorption begins to weaken during heating at 1100 deg C, but it is very persistent, surviving an anneal of 4 hours at 1400 deg C, albeit with diminished intensity. Three other weaker lines at 1438, 1358 and 1355 cm -1 develop with the 1450 cm -1 line, but differ from it and from each other in subsequent annealing behaviour. Other lines were observed; these are reported and discussed. (author)

Echographic monitoring of response of extraocular muscles to irradiation in graves' ophthalmopathy

International Nuclear Information System (INIS)

Erickson, Beth A.; Harris, Gerald J.; Lewandowski, Michael F.; Murray, Kevin J.; Massaro, Bruce M.

1995-01-01

Purpose: Confirmation of the efficacy of orbital irradiation in Graves' ophthalmopathy is needed due to the unpredictable natural history of the disease, the variation in individual clinical presentations, the contribution of other simultaneous treatments, and the lack of controlled studies using objective criteria to classify and assess response over time. Orbital echography before and at select intervals following orbital irradiation is proposed as an objective parameter of tissue response to orbital irradiation over time. Methods and Materials: From January, 1983 to September, 1993, 55 patients with progressive Graves' ophthalmopathy underwent 20 Gy retrobulbar irradiation. On retrospective review, standardized orbital echography was performed randomly prior to irradiation in 37 of the 55 patients to assess the acoustic characteristics of the extraocular muscles and to quantitate their individual and summed diameters. Twenty-one patients had at least one follow-up echographic evaluation at random intervals of 0 to 27.5 months following completion of irradiation. Twelve patients received steroids before or during irradiation, which were tapered in proximity to completion of radiation. Follow-up ranged from 2 to 65 months with the majority followed at least 6 months (18 patients). Results: Of the 21 patients with serial studies, 18 showed an interval decrease in individual and summed muscle size over time and return of symmetry. Interval improvement was documented as early as the 1 month follow-up study, with continued improvement seen during the 3-9 month studies, with stability typically achieved within 12 months. One patient had further changes between the 21 and 27.5 month follow-up studies. Exacerbation of disease was, however, echographically demonstrated in three patients at 6.5, 8.5, and 13 months. Follow-up studies in two of these patients again revealed improvement, one following tapered steroids. The third patient required orbital decompression

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)

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

Infrared irradiation of skin for the development of non-invasive health monitoring technologies

Science.gov (United States)

Abdussamad Abbas, Hisham; Triplett, Gregory

2015-06-01

Infrared radiation was employed to study the optical transmission properties of pigskin and the factors that influence transmission at room temperature. The skin samples from the forehead of piglets were irradiated using an infrared-pulsed source by varying the beam properties such as optical power, power density, duty cycle, as well as sample thickness. Because infrared radiation in select instances can penetrate through thick-fleshy skin more easily than visible radiation, temperature fluctuations observed within the skin samples stemming from exposure-dependent absorption revealed interesting transmission properties and the limits of optical exposure. Pigskin was selected for this study since its structure most closely resembles that of human skin. Furthermore, the pulsed beam technique compared to continuous operation offers more precise control of heat generation within the skin. Through this effort, the correlated pulsed-beam parameters that influence infrared transmission were identified and varied to minimize the internal absorption losses through the dermis layers. The two most significant parameters that reduce absorption losses were frequency and duty cycle of the pulsed beam. Using the Bouger-Beer-Lambert Law, the absorption coefficient from empirical data is approximated, while accepting that the absorption coefficient is neither uniform nor linear. Given that the optical source used in this study was single mode, the infrared spectra obtained from irradiated samples also reveal characteristics of the skin structure. Realization of appropriate sample conditions and exposure parameters that reduce light attenuation within the skin and sample degradation could give way to novel non-invasive measuring techniques for health monitoring purposes.

ESR (Electronic Spin Resonance Spectroscopy) study of irradiated paper for biomedical material wrapping

International Nuclear Information System (INIS)

Huarte, Monica; Rubin de Celis, Emilio; Kairiyama, Eulogia; Zapata, Miguel; Santoro, Natalia; Magnavacca, Cecilia

2009-01-01

Ionising radiation treatments are used for sterilization, microbiological decontamination, disinfection, insect disinfestation and food preservation. This ionising radiation generates free radicals (FR) in matter, which can be detected by Electronic Spin Resonance Spectroscopy (ESR). For this work it had analysed different kind of irradiated package papers of syringes, surgical gloves and dressings by ESR. These were irradiated with doses between 20 and 35 kGy of gamma radiation (Cobalt 60). The processed samples were measured in a Bruker ECS 106 spectrometer. The obtained results were: 1-) The irritated samples showed a central peak and two satellites induced by the applied radiation; 2-) The non-irradiated samples did not show the characteristic satellite peaks of the irritated ones; 3-) A linear relationship between the signal heights per unit mass and the applied doses was found; and 4-) The signals were highly stable, with half-time values between 240 and 370 days for 20 and 30 kGy, permitting more than one year of monitoring proceedings. In conclusion, the ESR allows the detection, quantification and time monitoring processes of this kind of irradiated materials. (author) [es

Fuel irradiation experience at Halden

International Nuclear Information System (INIS)

Vitanza, Carlo

1996-01-01

The OECD Halden Reactor Project is an international organisation devoted to improved safety and reliability of nuclear power station through an user-oriented experimental programme. A significant part of this programme consists of studies addressing fuel performance issues in a range of conditions realised in specialised irradiation. The key element of the irradiation carried out in the Halden reactor is the ability to monitor fuel performance parameters by means of in-pile instrumentation. The paper reviews some of the irradiation rigs and the related instrumentation and provides examples of experimental results on selected fuel performance items. In particular, current irradiation conducted on high/very high burn-up fuels are reviewed in some detail

Comprehensive studies on irradiated single-crystal diamond sensors

Energy Technology Data Exchange (ETDEWEB)

Stegler, Martin [DESY, Zeuthen (Germany)

2015-07-01

Single-crystal diamond sensors are used as part of the Beam and Radiation Instrumentation and Luminosity (BRIL) projects of the CMS experiment. Due to an upgrade of the Fast Beam Conditions Monitor (BCM1F) these diamond sensors are exchanged and the irradiated ones are now used for comprehensive studies. Current over voltage (IV), current over time (CT) and charge collection efficiency (CCE) measurements were performed for a better understanding of the radiation damage incurred during operation and to compensate in the future. The effect of illumination with various light sources on the charge collection efficiency was investigated and led to interesting results. Intensity and wavelength of the light were varied for deeper insight of polarization effects.

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

Study of the recrystallisation of irradiated uranium

International Nuclear Information System (INIS)

Bloch, J.; Mustelier, J.P.; Bussy, P.; Blin, J.

1958-01-01

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 α-β 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 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) [fr

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)

Basic requirements to the methods of personnel monitoring

International Nuclear Information System (INIS)

Keirim-Markus, I.B.

1981-01-01

Requirements to methods of personnel monitoring (PMM) depending on irradiation conditions are given. The irradiation conditions determine subjected to monitoring types of irradiation, measurement ranges, periodicity of monitoring, operativeness of obtaining results and required accuracy. The PMM based on the photographic effect of ionizing radiation is the main method of the mass monitoring [ru

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

Study of irradiation damage by fast neutrons in samples of Portland cement

International Nuclear Information System (INIS)

Lucki, G.; Rosa Junior, A.A.

1984-01-01

The effect of neutron irradiation in samples of Portland cement was evaluated, using the resonance frequency method and pulse velocity of ultra-sound techniques. The samples were divided in three groups: 1) monitoring samples; 2) samples submitted to gamma heating; 3) Irradiated samples. In the sample preparation, it was used the Portland Santa Rita CP 320 cement, and water-cement rate of 0.40 l/Kg. The irradiation was done in the research reactor IEA-R1, at IPEN - CNEN/SP, with an integrated flux of 7.2 x 10 18 n/cm 2 (E approx. 1 MeV). Some damage were detected, due to the neutron flux, and by the thermal effect of gamma heating. (E.G.) [pt

Thermoluminescent and impedimetric studies on irradiated foodstuffs

International Nuclear Information System (INIS)

Mamoon, A.M.

2000-01-01

Several brands of different spices and milk powders were irradiated with relatively high doses of gamma radiation. Glow curves were produced upon heating these irradiated foodstuffs only. Study of the obtained spices glow curves revealed that the magnitude of these curves depends upon the dose received while the shape of the curves remains generally the same for the different doses and for the different spices. Previous studies had shown that the obtained thermoluminescence (TL) is due to dust particles carried by the spices. The TL studies show, furthermore, that different brands of the same spice are apparently contaminated with different amounts of dust or soil. The obtained TL from irradiated milk powders is apparently due to its mineral content. Different milk powders gave TL curves of different magnitudes for the same dose depending upon the milk brand. Impedimetric studies carried out irradiated potatoes show changes in impedance amplitude and phase angle. The results support earlier work on the use of TL to differentiate between irradiated and control foodstuffs, to assess the extent of spices contamination with soil-which perhaps reflects hygienic care-and that impedimetric measurements can distinguish irradiated from control potatoes

Study of irradiation effect on curcuma polyphenols

International Nuclear Information System (INIS)

Rejeb, Imen

2008-01-01

The present study was carried out to evaluate the effect of gamma irradiation on curcumin (Curcuma Longa rhizome) component, particularly the polyphenolic fraction. Powdered rhizome was irradiated at 0, 5, 10 and 15 KGy (dose rate of 6 KGy / H). Polyphenolics were extracted and total polyphenols conent (TPC) was quantified using the Folin-Ciocalteau method. The irradiation effect was also evaluated by the HPLC technique. The chromatographic analysis showed that the irradiated and non-irradiated curcumin spectrum gave similar data. The antioxidant and antibacterial activities of the phenolic extracts were also assessed. the anti oxidative potential of the sample was evaluated using two radical scavenging methods with DPPH and ABTS. The antimicrobial analysis showed that the phenolic extracts of curcumin inhibited the growth of the studied microorganisms. Our results showed that irradiated samples were not affected in terms of polyphenols content and characteristics. (Author)

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.

10 CFR 36.55 - Personnel monitoring.

Science.gov (United States)

2010-01-01

... 10 Energy 1 2010-01-01 2010-01-01 false Personnel monitoring. 36.55 Section 36.55 Energy NUCLEAR REGULATORY COMMISSION LICENSES AND RADIATION SAFETY REQUIREMENTS FOR IRRADIATORS Operation of Irradiators § 36.55 Personnel monitoring. (a) Irradiator operators shall wear a personnel dosimeter that is...

A study of positron irradiated porous silicon

International Nuclear Information System (INIS)

Huang Yuanming; Xue Qing; Zhai Baogai; Xu Aijun; Liu Shewen; Yu Weizhong

1998-01-01

The effect of positron irradiation on photoluminescence (PL) of porous silicon has been studied. After four hour positron irradiation, the red PL spectrum of porous silicon blue shifts into greenish spectral region, and a higher energy luminescence band is introduced into this blueshifted spectrum. The fourier transform infrared absorption experiment shows that the positron irradiation can cause further oxidization of porous silicon. A possible mechanism causing this change of PL spectra after positron irradiation is suggested

Assessment of population external irradiation doses with consideration of Rospotrebnadzor bodies equipment for monitoring of photon radiation dose

Directory of Open Access Journals (Sweden)

I. P. Stamat

2016-01-01

Full Text Available This paper provides review of equipment and methodology for measurement of photon radiation dose; analysis of possible reasons for considerable deviation between the Russian Federation population annual effective external irradiation doses and the relevant average global value. Data on Rospotrebnadzor bodies dosimetry equipment used for measurement of gamma radiation dose are collected and systematized. Over 60 kinds of dosimeters are used for monitoring of population external irradiation doses. Most of dosimeters used in the country have gas-discharge detectors (Geiger-Mueller counters, minor biochemical annunciators, etc. which have higher total values of own background level and of space radiation response than the modern dosimeters with scintillation detectors. This feature of dosimeters is apparently one of most plausible reasons of a bit overstating assessment of population external irradiation doses. The options for specification of population external irradiation doses assessment are: correction of gamma radiation dose measurement results with consideration of dosimeters own background level and space radiation response, introduction of more up-to-date dosimeters with scintillation detectors, etc. The most promising direction of research in verification of population external irradiation doses assessment is account of dosimetry equipment.

Standard irradiation facilities for use in TRIGA reactors

International Nuclear Information System (INIS)

Kolbasov, B.N.; Luse, R.A.

1972-01-01

The standard neutron irradiation facility (SNIP) was developed under IAEA and FAO co-ordinated research program for the standardization of neutron irradiation facilities for radiobiological research, resulting in the possibility to use fast neutrons from pool-type reactors for radiobiological studies. The studies include irradiation of seeds for crop improvement, of Drosophila for genetic studies, and of microorganisms for developing industrially useful mutants, as well as fundamental studies in radiation biology. The facilities, located in the six pool-type reactors (in Austria, Bulgaria, India, Philippines, Thailand and Taiwan), have been calibrated and utilized to compare the response to fast neutrons of barley seeds (variety Himalaya CI 000620) which were selected as a standard biological monitor by which to estimate neutron fluxes in different reactors. These comparative irradiation studies showed excellent agreement and reproducibility

Heavy ions amorphous semiconductors irradiation study

International Nuclear Information System (INIS)

Benmalek, M.

1978-01-01

The behavior of amorphous semiconductors (germanium and germanium and arsenic tellurides) under ion bombardment at energies up to 2 MeV was studied. The irradiation induced modifications were followed using electrical parameter changes (resistivity and activation energy) and by means of the transmission electron microscopy observations. The electrical conductivity enhancement of the irradiated samples was interpreted using the late conduction theories in amorphous compounds. In amorphous germanium, Electron Microscopy showed the formations of 'globules', these defects are similar to voids observed in irradiated metals. The displacement cascade theory was used for the interpretation of the irradiation induced defects formation and a coalescence mechanism of growth was pointed out for the vacancy agglomeration [fr

Studies on some irradiated food products

International Nuclear Information System (INIS)

Mohammed, H.M.B.

1998-01-01

The aim of this investigation was to study the possibility of using some doses of gamma irradiation and cold storage (4+1 C) for improving the hygienic quality and shelf-life of some meat products ( beef luncheon, processed minced beef and fresh beef sausage). luncheon meat samples were irradiated at doses of 4,6,8,10 and 12 k Gy, while beef and sausage samples were subjected to 4,6 and 8 KGy gamma rays doses and the effects of irradiation on the organoleptic properties, microbiological aspects and the chemical composition were studied during cold storage (4+1 C) of samples. Attention was focussed on the changes occurred in the organoleptic properties of these products by the evaluation of sensory scores for appearance, color and odor of samples post irradiation and during cold storage (4+1 C). In addition, the effects of treatments and cold storage on the microbiological quality by the determination of total bacterial count, total psychropilic bacteria, total coliforms, total molds and yeasts, staphylococcus aureus, streptococcus faecalis as well as the detection of salmonellae were studied

Study of irradiation creep of vanadium alloys

Energy Technology Data Exchange (ETDEWEB)

Tsai, H.; Strain, R.V.; Smith, D.L. [Argonne National Lab., IL (United States)] [and others

1997-08-01

Thin-wall tubing was produced from the 832665 (500 kg) heat of V-4 wt.% Cr-4 wt.% Ti to study its irradiation creep behavior. The specimens, in the form of pressurized capsules, were irradiated in Advanced Test Reactor and High Flux Isotope Reactor experiments (ATR-A1 and HFIR RB-12J, respectively). The ATR-A1 irradiation has been completed and specimens from it will soon be available for postirradiation examination. The RB-12J irradiation is not yet complete.

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).

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.)

Irradiation preservation processing study of strawberry

International Nuclear Information System (INIS)

Xu Shihong; Zhu Zhaodi

1992-01-01

Radiation preservation processing of strawberry was studied. The results show that single seal processing or combining with irradiation processing under given doses is of no practical value, but only combining with chill processing can promote lengthening period of fresh keeping. Single irradiation processing under given doses provides not only good initial state, but also the beginning of bad development at top speed on microorganism. The composite processing of irradiation, chill and seal can supply extended shelf lifetime with optimum value of dual synergetic effect

An experimental study on the change of bone mineral metabolism after irradiation

International Nuclear Information System (INIS)

Chin, Hae Yun; Lee, Sang Rae

1988-01-01

Irradiation is widely used for the treatment of malignant diseases, and possibly cause the osteoporosis. The bone densitometry and bone scintigraphy and valuable when used to monitor the patients longitudinally to access the progression of osteoporosis and risk of osteoradionecrosis. To evaluate the osteoporosis after irradiation of cobalt-60 gamma ray on the lumbar spines of New Zealand white rabbits, bone densitometry by dual photon absorptiometry and bone scintigraphy were performed weekly. The decrease of bone density began at the first week after irradiation, and were in the nadir at 4-6th week. The osteoblastic activity measured by bone scintigraphy decreased in the first week, and was in the nadir at 4-6th week. The severity of these changes were related to the radiation dose. In conclusion, the osteoporosis before presentation of the osteoradionecrosis can be developed at low dose irradiation and confirmed by bone densitometry, bone scanning, and histopathology.

Study on the irradiation port for wide spread use of carbon cancer therapy

International Nuclear Information System (INIS)

Komori, Masataka; Yonai, Shunsuke; Kanai, Tatsuaki

2006-01-01

A compact irradiation port for wide spread use of carbon radiotherapy is designed. The port length will be reduced to 5.5 m, which equal to half-length of Heavy Ion Medical Accelerator in Chiba (HIMAC). The broad beam method will be used to produce an irradiation field up to 220 mm in diameter and 250 mm in depth. We propose an amplitude-modulation wobbler method, so called spiral wobbler method, to produce the large irradiation field using a small radius beam. The system has an advantage that the residual range at an iso-center is longer than that produced by a conventional wobbler-scatterer method. An accurate dose estimation system will be introduced instead of measuring a calibration factor of dose monitor for each patient. In this project, we verify the design of the irradiation port and the dose estimation system. (author)

The Next Spaceflight Solar Irradiance Sensor: TSIS

Science.gov (United States)

Kopp, Greg; Pilewskie, Peter; Richard, Erik

2016-05-01

The Total and Spectral Solar Irradiance Sensor (TSIS) will continue measurements of the solar irradiance with improved accuracies and stabilities over extant spaceflight instruments. The two TSIS solar-observing instruments include the Total Irradiance Monitor (TIM) and the Spectral Irradiance Monitor (SIM) for measuring total- and spectral- solar-irradiance, respectively. The former provides the net energy powering the Earth’s climate system while the latter helps attribute where that energy is absorbed by the Earth’s atmosphere and surface. Both spaceflight instruments are assembled and being prepared for integration on the International Space Station. With operations commencing in late 2017, the TSIS is intended to overlap with NASA’s ongoing SOlar Radiation and Climate Experiment (SORCE) mission, which launched in 2003 and contains the first versions of both the TIM and SIM instruments, as well as with the TSI Calibration Transfer Experiment (TCTE), which began total solar irradiance measurements in 2013. We summarize the TSIS’s instrument improvements and intended solar-irradiance measurements.

AGC-4 Experiment Irradiation Monitoring Data Qualification Interim Report

International Nuclear Information System (INIS)

Hull, Laurence Charles

2016-01-01

The Graphite Technology Development Program is running a series of six experiments to quantify the effects of irradiation on nuclear grade graphite. The fourth experiment, Advanced Graphite Creep 4 (AGC 4), began with Advanced Test Reactor (ATR) cycle 157D on May 30, 2015, and has been irradiated for two cycles. The capsule was removed from the reactor after ATR cycle 158A, which ended on January 2, 2016, due to interference with another experiment. Irradiation will resume when the interfering experiment is removed from the reactor. This report documents qualification of AGC 4 experiment irradiation monitoring data for use by the Advanced Reactor Technologies (ART) Technology Development Office (TDO) Program for research and development activities required to design and license the first HTR nuclear plant. Qualified data meet the requirements for use as described in the experiment planning and quality assurance documents. Failed data do not meet the requirements and provide no useable information. Trend data may not meet all requirements, but still provide some useable information. Use of Trend data requires assessment of how any deficiencies affect a particular use of the data. All thermocouples (TCs) have functioned throughout the AGC-4 experiment. All temperature data are Qualified for use by the ART TDO Program. Argon, helium, and total gas flow data were within expected ranges and are Qualified for use by the ART TDO Program. Discharge gas line moisture values were consistently low during cycle 157D. At the start of cycle 158A, gas moisture briefly spiked to over 600 ppmv and then declined throughout the cycle. Moisture values are within the measurement range of the instrument and are Qualified for use by the ART TDO Program. Graphite creep specimens were subjected to one of three loads, 393, 491, or 589 lbf. For a brief period during cycle 157D between 12:19 on June 2, 2015 and 08:23 on June 11, 2015 the load cells were wired incorrectly resulting in missing

AGC-4 Experiment Irradiation Monitoring Data Qualification Interim Report

Energy Technology Data Exchange (ETDEWEB)

Hull, Laurence Charles [Idaho National Lab. (INL), Idaho Falls, ID (United States)

2016-08-01

The Graphite Technology Development Program is running a series of six experiments to quantify the effects of irradiation on nuclear grade graphite. The fourth experiment, Advanced Graphite Creep 4 (AGC 4), began with Advanced Test Reactor (ATR) cycle 157D on May 30, 2015, and has been irradiated for two cycles. The capsule was removed from the reactor after ATR cycle 158A, which ended on January 2, 2016, due to interference with another experiment. Irradiation will resume when the interfering experiment is removed from the reactor. This report documents qualification of AGC 4 experiment irradiation monitoring data for use by the Advanced Reactor Technologies (ART) Technology Development Office (TDO) Program for research and development activities required to design and license the first HTR nuclear plant. Qualified data meet the requirements for use as described in the experiment planning and quality assurance documents. Failed data do not meet the requirements and provide no useable information. Trend data may not meet all requirements, but still provide some useable information. Use of Trend data requires assessment of how any deficiencies affect a particular use of the data. All thermocouples (TCs) have functioned throughout the AGC-4 experiment. All temperature data are Qualified for use by the ART TDO Program. Argon, helium, and total gas flow data were within expected ranges and are Qualified for use by the ART TDO Program. Discharge gas line moisture values were consistently low during cycle 157D. At the start of cycle 158A, gas moisture briefly spiked to over 600 ppmv and then declined throughout the cycle. Moisture values are within the measurement range of the instrument and are Qualified for use by the ART TDO Program. Graphite creep specimens were subjected to one of three loads, 393, 491, or 589 lbf. For a brief period during cycle 157D between 12:19 on June 2, 2015 and 08:23 on June 11, 2015 the load cells were wired incorrectly resulting in missing

Cerenkov methodology for monitoring irradiated reactor fuel

International Nuclear Information System (INIS)

Nicholson, N.; Dowdy, E.J.

1984-01-01

Attribute measurement methods for confirming declared irradiated fuel inventories at nuclear installations under safeguards surveillance are of significant interest to inspectors. High-gain measurements of the intensity of the Cerenkov glow from exposed assemblies in water-filled storage ponds are promising for this purpose because the measured intensities depend on cooling times and burnup. We have developed a Cerenkov Measuring Device, a hand-held instrument that examines irradiated fuel assemblies in water-filled storage ponds and measures the intensity of the associated Cerenkov glow. In addition, we have developed a method for making such high-gain measurements in the presence of intense ambient light

Irradiation Embrittlement Monitoring Programs of RPV's in the Slovak Republic NPP's

International Nuclear Information System (INIS)

Kupca, Ludovik

2006-01-01

Four types of surveillance programs were (are) realized in Slovak NPP's: 'Standard Surveillance Specimen Program' (SSSP) was finished in Jaslovske Bohunice V-2 Nuclear Power Plant (NPP) Units 3 and 4, 'Extended Surveillance Specimen Program' (ESSP), was prepared for Jaslovske Bohunice NPP V-2 with aim to validate the SSSP results, For the Mochovce NPP Unit 1 and 2 was prepared completely new surveillance program 'Modern Surveillance Specimen Program' (MSSP), based on the philosophy that the results of MSSP must be available during all NPP service life, For the Bohunice V-1 NPP was finished 'New Surveillance Specimen Program' (NSSP) coordinated by IAEA, which gave arguments for prolongation of service life these units for minimum 20 years, New Advanced Surveillance Specimen Program (ASSP) for Bohunice V-2 NPP (units 3 and 4) and Mochovce NPP (units 1, 2) is approved now. ASSP is dealing with the irradiation embrittlement of heat affected zone (HAZ) and RPV's austenitic cladding, which were not evaluated till this time in surveillance programs. SSSP started in 1979 and was finished in 1990. ESSP program started in 1995 and will be finished in 2007, was prepared with aim of: increasing of neutron fluence measurement accuracy, substantial improvement the irradiation temperature measurement, fixed orientation of samples to the centre of the reactor core, minimum differences of neutron dose for all the Charpy-V notch and COD specimens, the dose rate effect evaluation. In the year 1996 was started the new surveillance specimen program for the Mochovce RPV's unit-1 and 2, based on the fundamental postulate - to provide the irradiation embrittlement monitoring till the end of units operation. The 'New Surveillance Specimen Program' (NSSP) prepared in the year 1999 for the Bohunice V-1 NPP was finished in the year 2004. Main goal of this program was to evaluate the weld material properties degradation due to the irradiation and recovery efficiency by annealing too. The

Investigations of food irradiation technology in Japan

International Nuclear Information System (INIS)

2009-01-01

All Nippon Spice Assoc. (ANSA) requested the approval in the Ministry of Health Labour and Welfare (MHLW) of radiation irradiation of their products for sterilization and pesticide in 2000. Problems of food irradiation (FI) which started from this ANSA request have been investigated by concerned Japanese administrations and associations with reference to trends in foreign countries, and of which outline till Aug., 2009 is described in this paper. On ANSA petition, AEC (Atomic Energy Committee) required the investigation of the safety problem in FI as it matched AEC policy and there have been background problems of Japanese people who have been having refusal response to radiation themselves. In 2003, Food Safety Committee (FSC) started, and AEC radiation expert committee investigated the trend and detection methodology of irradiated foods. Next year, FSC approved the irradiation of potato to prevent budding; MHLW began to study the detection methodology; and AEC mentioned to consider the FI problem in the Cabinet meeting and set up its expert committee (2005). MHLW reported the above decision in Councils of food/drug and of food hygiene (2006), published the methodology (thermoluminescence method) and started to monitor spices; and FSC discussed about FI problems with World Health Organization (WHO) experts (2007). During these years, the administrations trusted various investigations like foreign trends, safety and assessment of FI. In 2009, MHLW published results of their trusted investigations, based on which food hygienic and standardization sections began to investigate the problems; and FSC, the toxicity study of alkylcyclobutanone. During the period later than 2007, not only spices but also other foods like dried vegetables, tea, certain farm and marine products have been subject to monitoring (MHLW). Thus, MHLW has taken a leading role in actual approval of irradiated potato and in monitoring of imported foods. (K.T.)

Neutron self-shielding with k0-NAA irradiations

International Nuclear Information System (INIS)

Chilian, C.; Chambon, R.; Kennedy, G.

2010-01-01

A sample of SMELS Type II reference material was mixed with powdered Cd-nitrate neutron absorber and analysed by k 0 NAA for 10 elements. The thermal neutron self-shielding effect was found to be 34.8%. When flux monitors were irradiated sufficiently far from the absorbing sample, it was found that the self-shielding could be corrected accurately using an analytical formula and an iterative calculation. When the flux monitors were irradiated 2 mm from the absorbing sample, the calculations over-corrected the concentrations by as much as 30%. It is recommended to irradiate flux monitors at least 14 mm from a 10 mm diameter absorbing sample.

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

Facilities for studying radiation damage in nonmetals during irradiation

International Nuclear Information System (INIS)

Levy, P.W.

1984-08-01

Two facilities have been developed for making optical absorption, luminescence and other measurements on a single sample before, during and after irradiation. One facility uses 60 Co gamma rays and the other 0.5 to 3 MeV electrons from an accelerator. Optical relays function as spectrophotometers, luminescenc detectors, etc. All radiation sensitive components are outside of walk-in irradiation chambers; all measurement control and data recording is computerized. Irradiations are made at controlled temperatures between 5K and 900 0 C. The materials studied include glasses, quartz, alkali halides (especially natural rock salt), organic crystals, etc. As determined from color center measurements the damage formation rate in all materials studied at 25 0 C or above is strongly temperature dependent. The defect concentration during irradiation is usually much greater than that measured after irradiation. The fraction of defects annealing after irradiation and the annealing rate usually increases as the irradiation temperature increases. The completed studies demonstrate that, in most cases, the extent of maximum damage and the damage formation and annealing kinetics can be determined only by making measurements during irradiation

Wholesomeness studies in the International Food Irradiation Project

Energy Technology Data Exchange (ETDEWEB)

Elias, P S [International Food Irradiation Project, Federal Research Centre for Nutrition

1980-01-01

Despite more than 25 years of history as an effective food preservation method, food irradiation is still subject to strict legislative control in many countries and scientific investigations are required to provide reassurance as to the safety of irradiated food. The International Food Irradiation Project was set up on October 14, 1970 to facilitate the objective evaluation of the wholesomeness of irradiated foodstuffs. Its major activities are; (1) wholesomeness testing of irradiated foods, (2) research on and investigations into the methodology of wholesomeness testing, (3) dissemination of information, and (4) assisting national and international authorities in their consideration of acceptance of irradiated food. In particular, the project over the past nine years had been devoted to the provision of data to national health authorities and international bodies. Up to now, 23 studies were and are being carried out for the project under contract. Subjects for the studies include wheat, wheat flour, potatoes, fish, rice, mango, spices, dried dates, onions and cocoa beans.

Wholesomeness studies in the International Food Irradiation Project

International Nuclear Information System (INIS)

Elias, P.S.

1980-01-01

Despite more than 25 years history as an effective food preservation method, food irradiation is still subject to strict legislative control in many countries and it is required to carry out scientific investigations to reassure the safety of irradiated food. The International Food Irradiation Project was set up on October 14, 1970 to facilitate the objective evaluation of the wholesomeness of irradiated foodstuffs. Its major activities are; (1) wholesomeness testing of irradiated foods, (2) research on and investigations into the methodology of wholesomeness testing, (3) dissemination of information, and (4) assisting national and international authorities in their consideration of acceptance of irradiated food. In particular, the project over the past nine years had been devoted to the provision of data to national health authorities and international bodies. Up to now, 23 studies were and are being carried out for the project under contract. Subject to the studies include wheat, wheat flour, potatoes, fish, rice, mango, spices, dried dates, onions and cocoa beans. (Kitajima, A.)

Study for the identification of irradiated carbohydrate containing food

International Nuclear Information System (INIS)

Scherz, H.

1991-01-01

The study was undertaken to find radiation specific substances of carbohydrates and methods to detect those ones in irradiated food. Deoxycompounds have been found by irradiation of carbohydrates. It could be stated, that the formation of these substances was radiation specific. The irradiation of wheat for desinfestation was high actual at the moment of this study and therefore it was tried to find these deoxycompounds in irradiated potato starch and wheat flour. These substances were isolated and one of them was identified as w-hydroxymaltol. This substance was also found in irradiated wheat flour. The dependence between the amount of w-hydroxymaltol and the irradiation dosage was determined for both materials. (7 refs, 2 figs)

Electron microscope study of irradiated beryllium oxide

International Nuclear Information System (INIS)

Bisson, A.A.

1965-06-01

The beryllium oxide is studied first by fractography, before and after irradiation, using sintered samples. The fractures are examined under different aspects. The higher density sintered samples, with transgranular fractures are the most interesting for a microscopic study. It is possible to mark the difference between the 'pores' left by the sintering process and the 'bubbles' of gases that can be produced by former thermal treatments. After irradiation, the grain boundaries are very much weakened. By annealing, it is possible to observe the evolution of the gases produced by the reaction (n, 2n) and (n. α) and gathered on the grain boundaries. The irradiated beryllium oxide is afterwards studied by transmission. For that, a simple method has been used: little chips of the crushed material are examined. Clusters of point defects produced by neutrons are thus detected in crystals irradiated at the three following doses: 6 x 10 19 , 9 x 10 19 and 2 x 10 20 n f cm -2 at a temperature below 100 deg. C. For the irradiation at 6 x 10 19 n f cm -2 , the defects are merely visible, but at 2 x l0 20 n f cm -2 the crystals an crowded with clusters and the Kikuchi lines have disappeared from the micro-diffraction diagrams. The evolution of the clusters into dislocation loops is studied by a series of annealings. The activation energy (0,37 eV) calculated from the annealing curves suggests that it must be interstitials that condense into dislocation loops. Samples irradiated at high temperatures (650, 900 and 1100 deg. C) are also studied. In those specimens the size of the loops is not the same as the equilibrium size obtained after out of pile annealing at the same temperature. Those former loops are more specifically studied and their Burgers vector is determined by micro-diffraction. (author) [fr

Study on cytotoxicities induced by alpha particle irradiation combined with NNK treatment

International Nuclear Information System (INIS)

Li Ping; Yang Zhihua; Pan Xiujie; Cao Zhenshan; Mi Na; Chen Zhongmin; Liu Gang; Wei Han; Li Huiyin; Zhu Maoxiang

2006-01-01

Objective: To investigate cytotoxicities of alpha-particle irradiation combined with NNK treatment. Methods: Exponentially growing immortalized human bronchial epithelial cells were divided into normal control group (NC), alpha particle irradiation group (α), NNK administration group (NNK), NNK administration (100 μg/ml) followed by alpha particle irradiation group (NNK + α), and alphaparticle irradiation followed by NNK administration (100 μg/ml) group (α + NNK). Cell survival fractions were measured by cloning rate of low-density plating cell. Ethidium bromide and 2', 7'-dichlorofluorescein, fluorescent products of the membrane-permeable dyes hydroethine and 2', 7'-dichloroflurescindiacetate were used to monitor the inarticulate reactive oxygen species (ROS) . Damage to membrane permeability was evaluated through testing LDH activity in medium. Results: In the groups exposed to both alpha particles and NNK, the survival rates were significantly lower than that of the groups administrated with the same dose of alpha particles or NNK alone. The levels of intracellular ROS and the activity of LDH in medium were significantly higher than that of the groups administrated with the same dose of alpha particles or NNK alone. Subtracted the NNK effect, the survival rates of the groups received both alpha particle irradiation and NNK treatment were significantly lower than that of alpha particle irradiated only group. However, the intracellular ROS level and the activity of LDH in medium were significantly higher than that of alpha-particle irradiated only group. In addition, the survival rates of the cells in groups exposed to alpha particle irradiation followed by NNK administration were significantly lower than that of cells treated with NNK administration followed by alpha particle irradiation. Conclusions: Alpha particle irradiation and NNK administration had synergisticity in cytotoxicity, and furthermore different schedules of the administration resulted in

Monitoring, genomic study and control of patulin producing fungi in Korean fruits

International Nuclear Information System (INIS)

Kim, Dongho; Lim, Sangyong; Joe, Minho; Yun, Hyejung; Kim, Suhyun; Park, Jongchun

2008-07-01

This study was intended to apply irradiation technology for the degradation of patulin from apples and apple juices by investigating their physical, mechanical, biological, and pharmacochemical properties in view of potential uses in the bio-industry. The patulin producing fungi was separated from in Korean apples. Totally, 16 morphological types of fungi were isolated from the apples and a patulin producing fungi was identified. The isolated patulin producing fungus was found to a represent species of Penicillium crustosum. The patulin, dissolved in distilled water at a concentration of 50 ppm was practically degraded by the gamma irradiation at the dose of 1.0 kGy, while 33% of the patulin was remained at apple juice. In conclusion, it was suggested that 1 kGy of gamma irradiation (recommended radiation doses for radicidation and/or quarantine in fruits) is effective for the reduction of patulin, but the nutritional elements should be considered because the radio-degradation effects are environment dependant. The effects of a gamma irradiation on the physiochemical and physical characteristics of apple was investigated during a post-irradiation storage at 4 and 25. Gamma irradiation dose not affect stability of the nutritional contents, functional properties and physical characteristics of apples, especially in the condition of a cold storage after a radiation treatment. The degradation condition characteristics of patulin in apple juice and functional properties of corresponding condition were monitored by response surface methodology (RSM)

Monitoring, genomic study and control of patulin producing fungi in Korean fruits

Energy Technology Data Exchange (ETDEWEB)

Kim, Dongho; Lim, Sangyong; Joe, Minho; Yun, Hyejung [KAERI, Daejeon (Korea, Republic of); Kim, Suhyun [KBSI, Daejeon (Korea, Republic of); Park, Jongchun [Seonam Univ., Asan (Korea, Republic of)

2008-07-15

This study was intended to apply irradiation technology for the degradation of patulin from apples and apple juices by investigating their physical, mechanical, biological, and pharmacochemical properties in view of potential uses in the bio-industry. The patulin producing fungi was separated from in Korean apples. Totally, 16 morphological types of fungi were isolated from the apples and a patulin producing fungi was identified. The isolated patulin producing fungus was found to a represent species of Penicillium crustosum. The patulin, dissolved in distilled water at a concentration of 50 ppm was practically degraded by the gamma irradiation at the dose of 1.0 kGy, while 33% of the patulin was remained at apple juice. In conclusion, it was suggested that 1 kGy of gamma irradiation (recommended radiation doses for radicidation and/or quarantine in fruits) is effective for the reduction of patulin, but the nutritional elements should be considered because the radio-degradation effects are environment dependant. The effects of a gamma irradiation on the physiochemical and physical characteristics of apple was investigated during a post-irradiation storage at 4 and 25. Gamma irradiation dose not affect stability of the nutritional contents, functional properties and physical characteristics of apples, especially in the condition of a cold storage after a radiation treatment. The degradation condition characteristics of patulin in apple juice and functional properties of corresponding condition were monitored by response surface methodology (RSM)

Study of inhibition on lipid oxidation of irradiated pork

International Nuclear Information System (INIS)

Ha Yiming

2006-03-01

It was studied that the effect factors of irradiation dose, preservation temperature, oxygen content and antioxidant on lipid oxidation of irradiated pork. A mechanism was explained on lipid oxidation of irradiated pork. The results showed that irradiation might aggravate lipid oxidation of pork and that decreased preservation temperature and oxygen content of the packaging, added antioxidant also could effectively inhibit lipid oxidation of irradiated pork. (authors)

Performance studies of the vibration wire monitor on the test stand with low energy electron beam

International Nuclear Information System (INIS)

Okabe, Kota; Yoshimoto, Masahiro; Kinsho, Michikazu

2015-01-01

In the high intensity proton accelerator as the Japan Proton Accelerator Research Complex (J-PARC) accelerators, serious radiation and residual dose is induced by a small beam loss such a beam halo. Therefore, diagnostics of the beam halo formation is one of the most important issues to control the beam loss. For the beam halo monitor, the vibration wire monitor (VWM) has a potential for investigating the beam halo and weak beam scanning. The VWM has a wide dynamic range, high resolution and the VWM is not susceptible to secondary electrons and electric noises. We have studied the VWM features as a new beam-halo monitor on the test stand with low energy electron gun. The frequency shift of the irradiated vibration wire was confirmed about wire material and the electron beam profile measured by using the VWM was consistent with the results of the Faraday cup measurement. Also we calculated a temperature distribution on the vibration wire which is irradiated by the electron beam with the numerical simulation. The simulations have been fairly successful in reproducing the transient of the irradiated vibration wire frequency measured by test stand experiments. In this paper, we will report a result of performance evaluation for the VWM on the test stands and discuss the VWM for beam halo diagnostic. (author)

Biochemical and Tissue Studies on Post Irradiation Recovery in Mammals

International Nuclear Information System (INIS)

Abdou, M.I.M.

2004-01-01

three main studies were performed in this thesis, namely, mortality and survival study, biochemical studies, and studies on tissue alterations cobalt-60 gamma irradiation for low let was used for the external whole body irradiation of the irradiated animal groups. a total number of animals of 722 virgin female adult wister rats of approximately the same age and weight were used for the three studies that were performed, including the control and irradiated animal groups. the animals were housed and kept with special care at fixed temperature, humidity and diet. the study on mortality and survival included 370 animals divided into control and groups irradiated with 4,5,6,7,8 and 9 Gy. this study was followed up for one year to record the number and date of animal deaths for the different irradiated groups. for the 8 and 9 Gy irradiated groups the follow up ended after 12 weeks and 11 days respectively when animal mortality reached 100%. the maximum percent mortality was noted at the second week (3.3,8,14 and 29%) for the 4,5,6 and 7 Gy irradiated groups respectively. for the 8 and 9 Gy irradiated groups, the maximum percent mortality was noted at the first week (42.9 and 90% respectively). regression equations were applied for the percent of mortality of the 5-8 Gy irradiated groups to estimate the LD 50/30, which was found to be 6.4 Gy

Consumer acceptance of irradiated food products: an apple marketing study

International Nuclear Information System (INIS)

Terry, D.E.; Tabor, R.L.

1990-01-01

This study was exploratory in nature, with emphasis on initial purchases and not repeat purchases or long-term loyalties to either irradiated or non-irradiated produce. The investigation involved the actual sale of irradiated and non-irradiated apples to consumers. Limited information about the process was provided, and apples were sold at roadside stands. Prices for the irradiated apples were varied while the price for the non-irradiated apples was held constant. Of these 228 West-Central Missouri shoppers, 101 (44%) bought no irradiated apples, 86 (38%) bought only irradiated apples, and 41 (18%) bought some of both types, Results of probit regressions indicated three significant independent variables. There was an inverse relationship between the price of irradiated apples and the probability of purchasing irradiated apples. There was a positive relationship between the purchasers’ educational level and the probability of purchasing irradiated apples. Predicted probabilities for belonging to categories in probit models were computed. Depending on particular equation specification, correctly placed were approximately 70 percent of the purchasers of the two categories--bought only non-irradiated apples, or bought some of both irradiated and non-irradiated apples or only irradiated apples. This study suggests that consumers may be interested in food irradiation as a possible alternative or supplement to current preservation techniques

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

AGC-3 Experiment Irradiation Monitoring Data Qualification Final Report

Energy Technology Data Exchange (ETDEWEB)

Laurence Hull

2014-10-01

The Graphite Technology Development Program will run a series of six experiments to quantify the effects of irradiation on nuclear grade graphite. The third experiment, Advanced Graphite Creep 3 (AGC 3), began with Advanced Test Reactor (ATR) Cycle 152B on November 27, 2012, and ended with ATR Cycle 155B on April 23, 2014. This report documents qualification of AGC 3 experiment irradiation monitoring data for use by the Very High Temperature Reactor (VHTR) Technology Development Office (TDO) Program for research and development activities required to design and license the first VHTR nuclear plant. Qualified data meet the requirements for data collection and use as described in the experiment planning and quality assurance documents. Failed data do not meet the requirements. Trend data may not meet the requirements, but may still provide some useable information. All thermocouples (TCs) functioned throughout the AGC 3 experiment. There was one interval between December 18, 2012, and December 20, 2012, where 10 NULL values were reported for various TCs. These NULL values were deleted from the Nuclear Data Management and Analysis System database. All temperature data are Qualified for use by the VHTR TDO Program. Argon, helium, and total gas flow data were within expected ranges and are Qualified for use by the VHTR TDO Program. Total gas flow was approximately 50 sccm through the AGC 3 experiment capsule. Helium gas flow was briefly increased to 100 sccm during ATR shutdowns. At the start of the AGC 3 experiment, moisture in the outflow gas line was stuck at a constant value of 335.6174 ppmv for the first cycle (Cycle 152B). When the AGC 3 experiment capsule was reinstalled in ATR for Cycle 154B, a new moisture filter was installed. Moisture data from Cycle 152B are Failed. All moisture data from the final three cycles (Cycles 154B, 155A, and 155B) are Qualified for use by the VHTR TDO Program.

Study on the Long Term Effects of Radiation on Irradiated Manawthukha Rice Grain (Mahsuri-M)

International Nuclear Information System (INIS)

Aye Aye Mar; Aye Aye Mon; Hnin Hnin Than; Ba Han; Tin Tin; Myint U

2008-03-01

Radioactivity monitoring of first and second generations Manawthukha paddy grain before cultivations were carried out. It was found out that there were no induced activity. Therefore it can be concluded that similarly it will be the same for third generation rice. The second generation rice was obtained from cultivation and harvesting of first generation [(i) non-irradiated (control), (ii) gamma-irradiated, (iii) neutron-one hour irradiated, (iv) neutron one-day irradiated rice]. Agronomical characteristics of three different types of generation of rice were studied. Morphological characteristics studies such as plant height, leaf width and panicle length,there was no large variation between three generations of rice. Phenotypes were found to be stable. Yield improvement was calculated. Nutritional values of rice generation were studied. They were (i) element analysis by different methods (NAA, EDXRF and AAS), vitamin determination and protein percent determination. There was no distinctive difference between first, second and third generation rice. In element analysis, eleven elements such as Mg, Mn, Na, K, Cl, Al, Ca, Fe, Zn, P and Cu were observed by NAA, AAS and EDXRF methods. Vitamin content (B1, B2) and protein content were also studied. Determination of amylose content, gel consistency and gelatinization temperature were involved in grain quality study. There was no large variation in three generations. Surface texture of first, second and third generation Manawthukha rice were studied by Scanning Electron Microscope (SEM). It was observed that the change of texture from generation to generation tend to become more distinctive in third generation.

1H-MR spectroscopy of the rat hippocampus after whole brain irradiation: an in vivo study

International Nuclear Information System (INIS)

Ding Weijun; Yang Haihua; Wang Xufeng; Hu Wei; Lei Hao; Li Chunxia; Fang Fang; Fang Zhouxi

2008-01-01

Objective: To study the relationships between dynamic changes of the hippocampus metabolites, cognitive impairment and ultrastructural changes of hippocampus in rats during the initial 4 weeks after 6 MV X-ray whole-brain irradiation. Methods: 65 rats were randomly divided into foul groups as sham control (n=5), 10 Gy, 20 Gy and 30 Gy groups (n=20). The learning and memory ability was measured with the Y maze test 4, 8 weeks, 2, 6 months after irradiation. 1 H-MRS was performed after 2 or 4 weeks' brain irradiation. The ultrastructural changes of the hippocampus were observed by electronic microscope. Results: The learning and memorizing ability of irradiation groups was significantly different from that of control group. Compared with control group, the NAA/Ct and Cho/Cr ratio in the left hippocampus in 10 Gy, 20 Gy and 30 Gy groups at 2 weeks and 4 weeks decreased significantly. Neuronal mitochondria edema, endothelial cells swelling and lamina dissociation in myelin sheath were demonstrated in various degrees by electromicroscope at 4 weeks following whole brain irradiation. Conclusions: 1 H-MRS can be used to non-invasively monitor the metabolic changes, both quantitatively and dynamically, of the irradiated rat brain, 1 H-MRS is superior to MRI in detecting early abnormality of the brain. The NAA/Cr and Cho/Cr ratio in irradiated hippocampus could reflect the severity of the brain injury to some extent. (authors)

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

Studies on potato irradiation in the G.D.R

International Nuclear Information System (INIS)

Luther, Th.; Huebner, G.; Grahn, Ch.; Doellstaedt, R.

1990-01-01

The studies of potato irradiation have been conducted in the framework of the National Food Irradiation Research Project for 4 years. Although in the G.D.R. the use of chemical sprout inhibitors is allowed, potato irradiation can be an alternative technique for potato processing. Before irradiation a wound healing period of approx. 2 weeks is absolutely necessary to protect the potatoes from Fusarium. The method that presents the minimum risk of damage is irradiation in containers. Economic evaluations for the irradiation of potatoes are also made. (author)

Cost/benefit study on date disinfestation by gamma irradiation in Algeria

International Nuclear Information System (INIS)

Mahlous, M.

2002-01-01

To establish the irradiation technology, one must have a holistic approach to the technology of food irradiation in order to assure a maximum utilization rate of the facility. The assumptions in this study are based on a free standing multipurpose irradiation facility, the throughput of which is expressed in t·kGy/year, and the unit cost of the treatment in US $/t·kGy. These values may then be applied for the calculation of the treatment cost of any food commodity, according to the irradiation dose needed. The study showed that irradiation treatment of dates is profitable and that the cost of irradiation does not exceed 1.6% of the selling price of the product. Post harvest losses may be considerably reduced thanks to irradiation treatment. A comparative study between irradiation and cold storage showed that irradiation will cost 30% less than cold storage. This study is completed by an evaluation of consumer acceptance of irradiated food products. (author)

An Experimental Study on the Change of Bone Mineral Metabolism After Irradiation

International Nuclear Information System (INIS)

Hong, Sung Woon; Lim, Sang Moo; Jang, Ja June; Lee, Jin Oh; Kang, Tae Woong

1990-01-01

Irradiation is widely used for the treatment of malignant diseases, and possibly cause the osteoporosis. The densitometry and bone scintigraphy are valuable when used to monitor the patients longitudinally to access the progression of osteoporosis and risk of osteoradionecrosis. To evaluate the osteoporosis after irradiation of Cobalt-60 gamma ray on the lumbar spines of New Zealand white rabbits, bone densitometry by dual photon absorptiometry and bone scintigraphy were performed weekly. The decrease of bone density began at the first week after irradiation, and were in the nadir at 4-6th week. The osteoblastic activity measured by bone scintigraphy decreased in the first week, and was in the nadir at 4-6th week. The severity of these changes were related to the radiation dose. In conclusion, the osteoporosis before the presentation of the osteoradionecrosis can be diagnosed early with the dual photon absorptiometry and bone scintigraphy.

Study on determination method of identifying irradiated chicken

International Nuclear Information System (INIS)

Guo Liping; Yu Xuejun; Yu Menghong; Fu Junjie; Zhang Shimin; Bao Jinsong

2003-01-01

The effects of gamma irradiation on the activities of aleipsis, peroxidase, perhydrol catalase and the peroxide values in chicken oil and effects of different storage time on self-oxidation of fat and lipa in irradiated chicken were studied. The results showed that the activities of aleipsis and perhydrol catalase in irradiated chicken decreased with increasing doses, and the peroxide activity and peroxide value of lipa increased with increase of doses. No significant effect of storage time on peroxide value was observed in the irradiated chicken

Some wholesomeness studies on irradiated Iraqi dates

International Nuclear Information System (INIS)

Al Rawi, A.M.; Hamoudi, H.I.

1981-01-01

Iraqi dates (Zahdi and Khestawi) were irradiated at different dose levels (0 to 1500 krad) to extend their shelf-lives. Samples irradiated at 150 krad showed no change in the behaviour studies of tested Swiss albino mice. Fungi were found to have a constant rate of growth on the syrup irradiated dates. Chemical products such as malondialdehyde, deoxy sugars, acids and reducing sugars were quantified. In conclusion, 150 krad is a convenient dose to extend the shelf-lives of the tested dates and is therefore recommended. (author)

Structural and optical studies of 100 MeV Au irradiated thin films of tin oxide

Science.gov (United States)

Jaiswal, Manoj Kumar; Kanjilal, D.; Kumar, Rajesh

2013-11-01

Thin films of tin(IV) oxide (SnO2) of 100 nm thickness were grown on silicon (1 0 0) matrices by electron beam evaporation deposition technique under high vacuum. The thicknesses of these films were monitored by piezo-sensor attached to the deposition chamber. Nanocrystallinity is achieved in these thin films by 100 MeV Au8+ using 1 pnA current at normal incidence with ion fluences varying from 1 × 1011 ions/cm2 to 5 × 1013 ions/cm2. Swift Heavy Ion beam irradiation was carried out by using 15 UD Pelletron Accelerator at IUAC, New Delhi, India. Optical studies of pristine and ion irradiated thin films were characterized by UV-Visible spectroscopy and Fourier Transform Infrared (FTIR) spectroscopy. Prominent peak at 610 cm-1 in FTIR spectrum confirmed the O-Sn-O bonding of tin(IV) oxide. For Surface topographical studies and grain size calculations, these films were characterized by Atomic Force Microscope (AFM) using Nanoscope III-A. Crystallinity and phase transformation due to irradiation of pristine and irradiated films were characterized by Glancing Angle X-ray Diffraction (GAXRD) using Brucker-D8 advance model. GAXRD results show improvement in crystallinity and phase transformation due to swift heavy ion irradiation. Grain size distribution was verified by AFM and GAXRD results. Swift heavy ion induced modifications in thin films of SnO2 were confirmed by the presence of prominent peaks at 2θ values of 30.65°, 32.045°, 43.94°, 44.96° and 52.36° in GAXRD spectrum.

[Alaskan commodities irradiation project: An options analysis study

International Nuclear Information System (INIS)

Zarling, J.P.; Swanson, R.B.; Logan, R.R.

1989-09-01

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

Development of Photostimulated Luminescence Technique for Detecting Irradiated Food

International Nuclear Information System (INIS)

Ros Anita Ahmad Ramli; Ahmad Zainuri Mohd Dzomir; Zainon Othman; Wan Saffiey Wan Abdullah; Muhamad Samudi Yasir

2015-01-01

The exposure of food to ionizing radiation is being progressively used in many countries to inactivate food pathogens, to eradicate pests and to extend shelf-life of food. To ensure free consumer choice, irradiated food will be labeled. The availability of a reliable method to detect irradiated food is important to enforce legal controls on labeling requirements, ensure proper distribution and increase consumer confidence. This paper reports on the preliminary application of photostimulated luminescence technique (PSL) as a potential method to detect irradiated food and perhaps be used for monitoring irradiated food on sale locally in the near future. Thus this study will be beneficial and relevant for application of food irradiation towards improving food safety and security in Malaysia. (author)

Study on silk yellowing induced by gamma-irradiation

International Nuclear Information System (INIS)

Tsukada, Masuhiro; Aoki, Akira

1985-01-01

The changes in the yellow color of silk threads with total dose of irradiation applied were described and studied by a colorimetric method and by monochrome photography. The change into a yellow color of the specimen in the course of irradiation was clearly detected in photographs using filters, 2B and SC 56 under light conditions at the wavelength of 366 nm. The b/L value measured by colorimetry in undegummed and degummed silk fibers sharply increased in the early stage of irradiation. Yellow color indices (b/L) of the specimen subjected to gamma-irradiation continued to increase and the yellow color of the silk threads became more pronounced above a total dose of irradiation of 21 Mrad. The b/L value of the undegummed silk fiber which had deen irradiated was about 2 times that of the degummed silk fiber. (author)

Real-time electron-beam dose monitoring

International Nuclear Information System (INIS)

McKeown, J.

1995-01-01

A new technique to monitor the integrated dose that a product receives in an irradiation facility is determined by collecting the charge that passes through the product. The technique allows the absorbed dose to be monitored as the irradiation is taking place, i.e. on-line and in real time. The procedure will also provide a means of directly measuring the electron energy, independent of the accelerator control system. The irradiation plant operator can immediately detect a problem of inadequate electron energy and take appropriate action. Examples taken on the IMPELA trademark accelerator at the Iotron Irradiation Facility in Vancouver are presented

Study of an automatized experimental device for the irradiation of a radioactive target

International Nuclear Information System (INIS)

Claverie, G.

1996-01-01

In order to solve the enigma of solar neutrinos, a team of physicians of the nuclear research center of Bordeaux-Gradignan and of the center of nuclear spectroscopy and mass spectroscopy of Orsay (France) decided to measure again the cross section of the beryllium-proton nuclear reaction at the lowest possible energies. This measurement requires the design of an automatized experimental device to irradiate in a specific way a beryllium target with an accelerated proton beam. The aim of this work is the study of such a device for an energy range of 800 to 300 KeV. This device comprises a particle multi-detector and a shutter for the irradiation of the target and the counting of the reaction products according to a programmable time sequence. The advantage of this setup is to allow an important bombardment of the target and to ensure its cooling. This device is automatically controlled thanks to a micro-controller, actuators (step motors and electrostatic deflector). It includes some beam diagnosis elements controlled by step motors and a target temperature monitoring system controlling a safety valve. The management of the experiment cell vacuum has led to the design of a vacuum monitor allowing the precise follow up of the vacuum and the control of the safety valves of the device. The nuclear instrumentation necessary to be implemented for this measurement is also presented. (J.S.)

Electron spin resonance studies of some irradiated pharmaceuticals

International Nuclear Information System (INIS)

Gibella, M.; Crucq, A-S.; Tilquin, B.; Stocker, P.; Lesgards, G.; Raffi, J.

2000-01-01

Five antibiotics belonging to the cephalosporins and penicillins groups have been irradiated: anhydrous ampicilline acid, amoxicilline acid trihydrate, cefuroxime sodium salt, cloxacilline sodium salt monohydrate and ceftazidime pentahydrate. ESR studies have been carried out, showing the influence of irradiation and storage parameters on the nature and concentration of the free radicals trapped. These results may be used to detect an irradiation treatment on such pharmaceuticals. (author)

Pristine and γ-irradiated halloysite reinforced epoxy nanocomposites - Insight study

Science.gov (United States)

Saif, Muhammad Jawwad; Naveed, Muhammad; Zia, Khalid Mahmood; Asif, Muhammad

2016-10-01

The present study focuses on development of epoxy system reinforced with naturally occurring halloysite nanotubes (HNTs). A comparative study is presented describing the performance of pristine and γ-irradiated HNTs in an epoxy matrix. The γ-irradiation treatment was used for structural modification of natural pristine HNTs under air sealed environment at different absorbed doses and subsequently these irradiated HNTs were incorporated in epoxy resin with various wt% loadings. The consequences of γ-irradiation on HNTs were studied by FTIR and X-ray diffraction analysis (XRD) in terms of changes in functional groups and crystalline characteristics. An improvement is observed in mechanical properties and crack resistance of composites reinforced with γ-irradiated HNTs. The irradiated HNTs imparted an improved flexural and tensile strength/modulus along with better thermal performance.

Study on biologically active substances in irradiated apple juice

International Nuclear Information System (INIS)

Tencheva, S.

1975-01-01

The radiochemical changes proceeding by irradiation of foodstuffs rich in carbohydrates are studied. For the purpose pure solutions of D-glucose, D-fructose and sucrose and fresh apple juice, irradiated with 0,5 and 1,0 Mrad are investigated. Changes set in UV-spectra of the irradiated foodstuffs, the specific reaction of malonic dialdehyde formation with 2-thiobarbituric acid and the formation of carbonyl compounds reacting with 2,4-dinitro phenylhydrazine are studied. Results show that in the irradiated sample solutions of sugars and apple juice two peaks are formed. The malonic dialdehyde formation depends on the dose of irradiation applied. The newly formed carbonyl compounds both in the sample solutions and in the juice are 8 to 9 in number. (author)

Study of boron carbide evolution under neutron irradiation

International Nuclear Information System (INIS)

Simeone, D.

1999-01-01

Owing to its high neutron efficiency, boron carbide (B 4 C) is used as a neutron absorber in control rods of nuclear plants. Its behaviour under irradiation has been extensively studied for many years. It now seems clear that brittleness of the material induced by the 10 B(n,α) 7 Li capture reaction is due to penny shaped helium bubbles associated to a high strain field around them. However, no model explains the behaviour of the material under neutron irradiation. In order to build such a model, this work uses different techniques: nuclear microprobe X-ray diffraction profile analysis and Raman and Nuclear Magnetic Resonance Spectroscopy to present an evolution model of B 4 C under neutron irradiation. The use of nuclear reactions produced by a nuclear microprobe such as the 7 Li(p,p'γ) 7 Li reaction, allows to measure lithium profile in B 4 C pellets irradiated either in Pressurised Water Reactors or in Fast Breeder Reactors. Examining such profiles enables us to describe the migration of lithium atoms out of B 4 C materials under neutron irradiation. The analysis of X-ray diffraction profiles of irradiated B 4 C samples allows us to quantify the concentrations of helium bubbles as well as the strain fields around such bubbles.Furthermore Raman spectroscopy studies of different B 4 C samples lead us to propose that under neutron irradiation. the CBC linear chain disappears. Such a vanishing of this CBC chain. validated by NMR analysis, may explain the penny shaped of helium bubbles inside irradiated B 4 C. (author)

Study of irradiation damage structures in austenitic stainless steels

Energy Technology Data Exchange (ETDEWEB)

Hamada, Shozo [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

1997-08-01

The irradiation damage microstructures in austenitic stainless steels, which have been proposed to be a candidate of structural materials of a fusion reactor, under ions and neutrons irradiation have been studied. In ion irradiation experiments, cross-sectional observation of the depth distribution of damage formed due to ion irradiation became available. Comparison and discussion between experimental results with TEM and the calculated ones in the depth profiles of irradiation damage microstructures. Further, dual-phase stainless steels, consisted of ferritic/austenitic phases, showed irradiation-induced/enhanced precipitation during ion irradiation. High Flux Isotope Reactor with high neutron fluxes was employed in neutron-irradiation experiments. Swelling of 316 steel showed irradiation temperature dependence and this had strong correlation with phase instability under heavy damage level. Swelling resistance of Ti-modified austenitic stainless steel, which has good swelling resistance, decreased during high damage level. This might be caused by the instability of Ti-carbide particles. The preparation method to reduce higher radioactivity of neutron-irradiated TEM specimen was developed. (author). 176 refs.

Study of irradiation damage structures in austenitic stainless steels

International Nuclear Information System (INIS)

Hamada, Shozo

1997-08-01

The irradiation damage microstructures in austenitic stainless steels, which have been proposed to be a candidate of structural materials of a fusion reactor, under ions and neutrons irradiation have been studied. In ion irradiation experiments, cross-sectional observation of the depth distribution of damage formed due to ion irradiation became available. Comparison and discussion between experimental results with TEM and the calculated ones in the depth profiles of irradiation damage microstructures. Further, dual-phase stainless steels, consisted of ferritic/austenitic phases, showed irradiation-induced/enhanced precipitation during ion irradiation. High Flux Isotope Reactor with high neutron fluxes was employed in neutron-irradiation experiments. Swelling of 316 steel showed irradiation temperature dependence and this had strong correlation with phase instability under heavy damage level. Swelling resistance of Ti-modified austenitic stainless steel, which has good swelling resistance, decreased during high damage level. This might be caused by the instability of Ti-carbide particles. The preparation method to reduce higher radioactivity of neutron-irradiated TEM specimen was developed. (author). 176 refs

Pre- and post-irradiation fading effect for LiF:Mg,Ti and LiF:Mg,Cu,P materials used in routine monitoring

International Nuclear Information System (INIS)

Carinou, E.; Askounis, P.; Dimitropoulou, F.; Kiranos, G.; Kyrgiakou, H.; Nirgianaki, E.; Papadomarkaki, E.; Kamenopoulou, V.

2011-01-01

LiF is a well-known thermoluminescent (TL) material used in individual monitoring, and its fading characteristics have been studied for years. In the present study, the fading characteristics (for a period of 150 d) of various commercial LiF materials with different dopants have been evaluated. The materials used in the study are those used in routine procedures by the Personal Dosimetry Dept. of Greek Atomic Energy Commission and in particular, LiF:Mg,Ti (MTS-N, TL Poland), LiF:Mg,Cu,P (MCP-N, TL Poland), LiF:Mg,Cu,P (MCP-Ns, thin active layer detector, TL Poland) and LiF:Mg,Cu,P (TLD100H, Harshaw). The study showed that there is a sensitivity loss in signal of up to 20 % for the MTS-N material for a 150-d period in the pre-irradiation fading phase. The MCP-N has a stable behaviour in the pre-irradiation fading phase, but this also depends on the readout system. As far as the post-irradiation fading effect is concerned, a decrease of up to 20 % for the MTS-N material is observed for the same time period. On the other hand, the LiF:Mg,Cu,P material presents a stable behaviour within ±5 %. These results show that the fading effect is different for each material and should be taken into account when estimating doses from dosemeters that are in use for >2 months. (authors)

10 μ m-thick four-quadrant transmissive silicon photodiodes for beam position monitor application: electrical characterization and gamma irradiation effects

Science.gov (United States)

Rafí, J. M.; Pellegrini, G.; Quirion, D.; Hidalgo, S.; Godignon, P.; Matilla, O.; Juanhuix, J.; Fontserè, A.; Molas, B.; Pothin, D.; Fajardo, P.

2017-01-01

Silicon photodiodes are very useful devices as X-ray beam monitors in synchrotron radiation beamlines. Owing to Si absorption, devices thinner than 10 μ m are needed to achieve transmission over 90% for energies above 10 keV . In this work, new segmented four-quadrant diodes for beam alignment purposes are fabricated on both ultrathin (10 μ m-thick) and bulk silicon substrates. Four-quadrant diodes implementing different design parameters as well as auxiliary test structures (single diodes and MOS capacitors) are studied. An extensive electrical characterization, including current-voltage (I-V) and capacitance-voltage (C-V) techniques, is carried out on non-irradiated and gamma-irradiated devices up to 100 Mrad doses. Special attention is devoted to the study of radiation-induced charge build-up in diode interquadrant isolation dielectric, as well as its impact on device interquadrant resistance. Finally, the devices have been characterized with an 8 keV laboratory X-ray source at 108 ph/s and in BL13-XALOC ALBA Synchroton beamline with 1011 ph/s and energies from 6 to 16 keV . Sensitivity, spatial resolution and uniformity of the devices have been evaluated.

Irradiation tests of ATLAS liquid argon forward calorimeter (FCAL) electronics components

CERN Document Server

Leroy, C; Golikov, V; Golubyh, S M; Kukhtin, V; Kulagin, E; Luschikov, V; Merkulov, L; Minashkin, V F; Shalyugin, A N

2002-01-01

FCAL resistors, capacitors, and transformers together with capacitors and sintimid disks of the purity monitor have been irradiated in liquid argon to study their possible lead to argon pollution at a maximal neutron fluence of 1016 n cm-2 at the IBR-2 reactor of JINR, Dubna. The results of charge collection measurements before and after irradiation are reported. Electrical measurement on these FCAL capacitors, resistors and transformers were also performed after irradiation. In general, the results of resistance, capacitance, impedance, leakage current and high voltage breakdown measurements after irradiation show minor changes of value only for some parameters from nominal values or values measured before irradiation.

Food irradiation studies at the Institute of Nuclear Energy Research, Taiwan, Rep. of China

International Nuclear Information System (INIS)

Fu, Y.-K.; Tsai, C.-M.; Wu, W.-S.; Chang, M.-S.; Chang, Y.-N.; Shu, S.-L.

1981-01-01

The use of radiation to inhibit sprouting of potatoes, onions, gingers and garlic was studied at the Institute of Nuclear Energy Research. The sprout inhibition doses were found to be, 10, 5, 2.5, 7.5 Krads, respectively. Changes in the content of moisture, ash, reducing sugars, total sugars, lipids, proteins, fiber etc. were monitored in various agricultural foodstuffs both with and without γ-irradiation at various doses. Fungicides did not prevent potatoes from decaying at 10 or 25 0 C with or without gamma radiation. Onions treated with any fungicides have significantly more healthy tissues than controls at 10 0 C but not 25 0 C after 30 and 60 days storage, regardless of the presence or absence of gamma radiation. Insect pests have been causing great damage to stored rice in Taiwan. The four most harmful insects are: Sitophilus Zeamais Mostschulsky, Rhyzopertha dominica, Tribolitum custaneum Herbst and Sitotroga cerealella Oliver. Adults, eggs or larvae of these insect pests were irradiated by 60 Co gamma rays. The results show that 40 Krads of gamma-irradiation could completely control these four species of pests in stored rice. (author)

SORCE Level 3 Total Solar Irradiance Daily Average V016

Data.gov (United States)

National Aeronautics and Space Administration — The Total Solar Irradiance (TSI) data set SOR3TSID contains the total solar irradiance (a.k.a solar constant) data collected by the Total Irradiance Monitor (TIM)...

Feeding Studies of Irradiated Foods with Insects

Energy Technology Data Exchange (ETDEWEB)

Loaharanu, Srisan

1978-06-15

Insects are of value to man in many scientific studies. Microsomal detoxication systems exist in both insects and mammals. In the preliminary investigations it was found that irradiated cocoa beans and white and red kidney beans (Phaseolus spp.) did not significantly change the percentage of egg-hatch in the insects tested. In more detailed investigations food samples that are susceptible to insect spoilage and are representatives of widely consumed human foods were fed to various insect species. The development, sex distortion and reproductivity of the insects were investigated. Cytogenetic aberrations as related to dominant lethality were studied in insects with reasonably clear chromosomal patterns. The meiosis stage was examined, using the squash technique and Aceto-orcein staining. Black beans, Phaseolus spp., irradiated with up to 200 krad of gamma rays did not apparently change the percentage of survival and the sex ratio of the bean weevil, Zabrotes subfasciatus. Dominant lethality in the German cockroach, Blatella germanica, fed on irradiated black beans did not apparently occur when considering the results of cytological investigation and the number of offspring obtained. Dried sardine samples irradiated with up to 400 krad of gamma rays neither apparently affected the survival nor caused sex distortion in the cheese skipper, Piophila casei. This irradiated product apparently did not induce dominant lethality in the German cockroach as tested. Coffee processed from coffee beans that had been irradiated with up to 100 krad of gamma rays did not apparently cause adverse effects on the experimental insects. (author)

Feeding studies of irradiated foods with insects

International Nuclear Information System (INIS)

Loaharanu, S.

1978-01-01

Insects are of value to man in many scientific studies. Microsomal detoxication systems exist in both insects and mammals. In the preliminary investigations it was found that irradiated cocoa beans and white and red kidney beans (Phaseolus spp.) did not significantly change the percentage of egg-hatch in the insects tested. In more detailed investigations food samples that are susceptible to insect spoilage and are representatives of widely consumed human foods were fed to various insect species. The development, sex distortion and reproductivity of the insects were investigated. Cytogenetic aberrations as related to dominant lethality were studied in insects with reasonably clear chromosomal patterns. The meiosis stage was examined, using the squash technique and Aceto-orcein staining. Black beans, Phaseolus spp., irradiated with up to 200 krad of gamma rays did not apparently change the percentage of survival and the sex ratio of the bean weevil, Zabrotes subfasciatus. Dominant lethality in the German cockroach, Blatella germanica, fed on irradiated black beans did not apparently occur when considering the results of cytological investigation and the number of offspring obtained. Dried sardine samples irradiated with up to 400 krad of gamma rays neither apparently affected the survival nor caused sex distortion in the cheese skipper, Piophila casei. This irradiated product apparently did not induce dominant lethality in the German cockroach as tested. Coffee processed from coffee beans that had been irradiated with up to 100 krad of gamma rays did not apparently cause adverse effects on the experimental insects. (author)

Pristine and γ-irradiated halloysite reinforced epoxy nanocomposites – Insight study

International Nuclear Information System (INIS)

Saif, Muhammad Jawwad; Naveed, Muhammad; Zia, Khalid Mahmood; Asif, Muhammad

2016-01-01

The present study focuses on development of epoxy system reinforced with naturally occurring halloysite nanotubes (HNTs). A comparative study is presented describing the performance of pristine and γ-irradiated HNTs in an epoxy matrix. The γ-irradiation treatment was used for structural modification of natural pristine HNTs under air sealed environment at different absorbed doses and subsequently these irradiated HNTs were incorporated in epoxy resin with various wt% loadings. The consequences of γ-irradiation on HNTs were studied by FTIR and X-ray diffraction analysis (XRD) in terms of changes in functional groups and crystalline characteristics. An improvement is observed in mechanical properties and crack resistance of composites reinforced with γ-irradiated HNTs. The irradiated HNTs imparted an improved flexural and tensile strength/modulus along with better thermal performance. - Highlights: • The γ-irradiation was used for structural modification of halloysite nanotubes. • Composite materials with irradiated HNTs showed improved mechanical properties. • The γ-irradiation treatment is a promising surface modification method.

Modelling infrared temperature measurements: implications for laser irradiation and cryogen cooling studies

International Nuclear Information System (INIS)

Choi, B.; Pearce, J.A.; Welch, A.J.

2000-01-01

The use of thermographic techniques has increased as infrared detector technology has evolved and improved. For laser-tissue interactions, thermal cameras have been used to monitor the thermal response of tissue to pulsed and continuous wave irradiation. It is important to note that the temperature indicated by the thermal camera may not be equal to the actual surface temperature. It is crucial to understand the limitations of using thermal cameras to measure temperature during laser irradiation of tissue. The goal of this study was to demonstrate the potential difference between measured and actual surface temperatures in a quantitative fashion using a 1D finite difference model. Three ablation models and one cryogen spray cooling simulation were adapted from the literature, and predictions of radiometric temperature measurements were calculated. In general, (a) steep superficial temperature gradients, with a surface peak, resulted in an underestimation of the actual surface temperature, (b) steep superficial temperature gradients, with a subsurface peak, resulted in an overestimation, and (c) small gradients led to a relatively accurate temperature estimate. (author)

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)

Study of irradiation defects in GaAs

International Nuclear Information System (INIS)

Loualiche, S.

1982-11-01

Characterization techniques: C(V) differential capacity, DLTS deep level transient spectroscopy, DDLTS double deep level transient spectroscopy and DLOS deep level optical spectroscopy are studied and theoretical and experimental fundamentals are re-examined. In particular the centres created by ionic or electronic bombardment of p-type GaAs. New quantitative theoretical bases for the C(V) method are obtained. Study of the optical properties of traps due to irradiation using DLOS. The nature of irradiation defects are discussed [fr

Structural and optical studies of 100 MeV Au irradiated thin films of tin oxide

Energy Technology Data Exchange (ETDEWEB)

Jaiswal, Manoj Kumar [University School of Basic and Applied Sciences, Guru Gobind Singh Indraprastha University, New Delhi 110 078 (India); Kanjilal, D. [Inter University Accelerator Centre, Aruna Asaf Ali Marg, New Delhi 110 067 (India); Kumar, Rajesh, E-mail: rajeshkumaripu@gmail.com [University School of Basic and Applied Sciences, Guru Gobind Singh Indraprastha University, New Delhi 110 078 (India)

2013-11-01

Thin films of tin(IV) oxide (SnO{sub 2}) of 100 nm thickness were grown on silicon (1 0 0) matrices by electron beam evaporation deposition technique under high vacuum. The thicknesses of these films were monitored by piezo-sensor attached to the deposition chamber. Nanocrystallinity is achieved in these thin films by 100 MeV Au{sup 8+} using 1 pnA current at normal incidence with ion fluences varying from 1 × 10{sup 11} ions/cm{sup 2} to 5 × 10{sup 13} ions/cm{sup 2}. Swift Heavy Ion beam irradiation was carried out by using 15 UD Pelletron Accelerator at IUAC, New Delhi, India. Optical studies of pristine and ion irradiated thin films were characterized by UV–Visible spectroscopy and Fourier Transform Infrared (FTIR) spectroscopy. Prominent peak at 610 cm{sup −1} in FTIR spectrum confirmed the O–Sn–O bonding of tin(IV) oxide. For Surface topographical studies and grain size calculations, these films were characterized by Atomic Force Microscope (AFM) using Nanoscope III-A. Crystallinity and phase transformation due to irradiation of pristine and irradiated films were characterized by Glancing Angle X-ray Diffraction (GAXRD) using Brucker-D8 advance model. GAXRD results show improvement in crystallinity and phase transformation due to swift heavy ion irradiation. Grain size distribution was verified by AFM and GAXRD results. Swift heavy ion induced modifications in thin films of SnO{sub 2} were confirmed by the presence of prominent peaks at 2θ values of 30.65°, 32.045°, 43.94°, 44.96° and 52.36° in GAXRD spectrum.

Studies on preservation of agricultural products by irradiation

International Nuclear Information System (INIS)

Chung, K.H.; Kwon, S.H.; Lee, Y.I.; Chae, J.C.; Shin, I.C.

1981-01-01

This study was attempted to develop and establish the preservation techniques of agricultural products by irradiation through ascertainment of the optimum irradiation doses for sprout inhibition of white potato and chestnut, and for disinfestation of rice insects during storage

Irradiation temperature measurements in the surveillance program

International Nuclear Information System (INIS)

Pav, T.; Krhounek, V.

1991-01-01

Evaluation of the diamond monitor method for the determination of the irradiation temperature in the surveillance programme of WWER-440 reactors is discussed. One of the difficulties with the practical application of the method is that the measured values of irradiation temperature are unlikely high. Using a thermodynamical model of the processes in the annealing of the irradiated diamond crystals, it was shown that experimental difficulties came from the principles of the method used. An analysis was performed of the thermal field inside the capsule of the surveillance chain in operational conditions, using the finite element method. The diamond monitor method was suggested to be eliminated from the surveillance programme and the use was proposed of the value of 273+-3 degC (as the most likely value) for the irradiation temperature of surveillance samples in WWER-440 reactors. (Z.S.). 3 tabs., 6 figs., 4 refs

Development of photo stimulated luminescence technique for detecting irradiated food

International Nuclear Information System (INIS)

Ros Anita Ahmad Ramli; Ahmad Zainuri Mohd Dzomir; Zainon Othman; Wan Saffiey Wan Abdullah

2012-01-01

The exposure of food to ionizing radiation is being progressively used in many countries to inactivate food pathogens, to eradicate pests and to extend shelf-life of food. To ensure free consumer choice, irradiated food will be labeled. The availability of a reliable method to detect irradiated food is important to enforce legal controls on labeling requirements, ensure proper distribution and increase consumer confidence. This paper reports on the preliminary application of photo stimulated luminescence technique (PSL) as a potential method to detect irradiated food and perhaps be used for monitoring irradiated food on sale locally in the near future. Thus this study will be beneficial and relevant for application of food irradiation towards improving food safety and security in Malaysia. (author)

Monitoring longitudinal changes in irradiated head and neck cancer xenografts using diffuse reflectance spectroscopy

Science.gov (United States)

Vishwanath, Karthik; Jiang, Shudong; Gunn, Jason R.; Marra, Kayla; Andreozzi, Jacqueline M.; Pogue, Brian W.

2016-02-01

Radiation therapy is often used as the preferred clinical treatment for control of localized head and neck cancer. However, during the course of treatment (6-8 weeks), feedback about functional and/or physiological changes within impacted tissue are not obtained, given the onerous financial and/or logistical burdens of scheduling MRI, PET or CT scans. Diffuse optical sensing is well suited to address this problem since the instrumentation can be made low-cost and portable while still being able to non-invasively provide information about vascular oxygenation in vivo. Here we report results from studies that employed an optical fiber-based portable diffuse reflectance spectroscopy (DRS) system to longitudinally monitor changes in tumor vasculature within two head and neck cancer cell lines (SCC-15 and FaDu) xenografted in the flanks of nude mice, in two separate experiments. Once the tumor volumes were 100mm3, 67% of animals received localized (electron beam) radiation therapy in five fractions (8Gy/day, for 5 days) while 33% of the animals served as controls. DRS measurements were obtained from each animal on each day of treatment and then for two weeks post-treatment. Reflectance spectra were parametrized to extract total hemoglobin concentration and blood oxygen-saturation and the resulting time-trends of optical parameters appear to be dissimilar for the two cell-lines. These findings are also compared to previous animal experiments (using the FaDu line) that were irradiated using a photon beam radiotherapy protocol. These results and implications for the use of fiber-based DRS measurements made at local (irradiated) tumor site as a basis for identifying early radiotherapy-response are presented and discussed.

Progresses in studies on 2-alkylcyclobutanones in irradiated lipid-containing foods

International Nuclear Information System (INIS)

Zhang Haiwei; Ha Yiming; Wang Feng

2007-01-01

When foods are irradiated, the free fatty acids and triacylglycerides in the food are decomposed to 2-alkylcyclobutanones (2-ACBs), which have been one of the focuses in food irradiation studies since they were dis- covered in irradiated lipid-containing foods. As specific markers, 2-ACBs could be used to detect irradiated food. The production and stability of 2-ACBs are affected strongly by the irradiation does and temperature and preservation conditions, etc. On the other hand, potential health hazard assessments of 2-ACBs have been studied extensively. Re- cent progresses in 2-ACBs detecting methods from irradiated food, toxicological studies on 2-ACBs, and factors affecting production and stability of 2-ACBs are reviewed in this paper. (authors)

Facts about food irradiation: Genetic studies

International Nuclear Information System (INIS)

1991-01-01

Results published in the mid-1970s from the National Institute of Nutrition (NIN) in India showed increased numbers of polyploid cells in rats, mice, monkeys and malnourished children fed irradiated wheat products. This fact sheet considers the validity of these results. A large number of independent studies have been subsequently performed, and in none of these have results been obtained that support the NIN findings. The conclusion is that there is no evidence to link the consumption of irradiated food with any mutagenic effect. 3 refs

Techno-economic studies on transportable moving-bed onion irradiator

International Nuclear Information System (INIS)

Krishnamurthy, K.; Sharma, K.S.S.; Deshmukh, V.P.; Bongirwar, D.R.; Nair, K.V.V.; Patil, K.B.

1984-01-01

The paper presents the optimisation studies and the design features of a transportable irradiator evolved to demonstrate the techno-economic advantage of the irradiation process at village level. A brief outline is also given of the computer programme generated and employed to optimise the source-target configuration based on a narrow plane source moving-bed irradiation concept that aimed at achieving a simplified product handling system and cost effective design of the biological shield and controls for the irradiator. The engineering features of the irradiator along with a summary of the analysis of the economics of the application of the process are also given. (author)

Forecasting of the lethality in cases of nonuniform accidental irradiation (experimental studies at external gamma irradiation of rats)

International Nuclear Information System (INIS)

Ingilizova, K.

1983-01-01

A model is suggested that enables the prediction of death probability for the body (L) within the whole lethality dose range (DL 0 -DL 100 ), on the basis of predetermined physical characteristics: in cases of uneven external wholebody irradiation. Some biological effects of 4 variants of uneven irradiation have been studied, i.e. ventro-dorsal (V-D), dorso-ventral (D-V), cranio-caudal (Cr-Ca) and caudo-cranial (Ca-Cr). The following basic conclusions have been drawn: 1. The study of the biological effects of uneven irradiation, when estimated by the lethality factor, points out the lower efficiency of the former, if compared to even irradiation. 2. The even irradiation lethality in the conducted experiments, according to the ALE data and the postradiation mortality dynamics, is determined basically by the damage of the bloodforming tissue and the animals die of bone marrow syndrome. 3. The uneven irradiation, estimated by the total weight factor, is of lower efficiency than the even one. 4. The radiation-induced hypoplasia of the studied organs is exponential in character. 5. An original model for predicting radiation mortality in cases of uneven irradiation has been constructed. The model gives the possibility of relating the alterations in the index of biological efficiency reduction to the wholebody irradiation factor, as well as to the two systems with highest radiosensitivity: red bone marrow and the small intestine. The model helps determining the numerical value of death probability, depending on the average body irradiation doses and the integral unevenness factors for RBM. (author)

An AES Study of the Room Temperature Surface Conditioning of Technological Metal Surfaces by Electron Irradiation

OpenAIRE

Scheuerlein, C; Hilleret, Noël; Taborelli, M; Brown, A; Baker, M A

2002-01-01

The modifications to technological copper and niobium surfaces induced by 2.5 keV electron irradiation have been investigated in the context of the conditioning process occurring in particle accelerator ultra high vacuum systems. Changes in the elemental surface composition have been found using Scanning Auger Microscopy (SAM) by monitoring the carbon, oxygen and metal Auger peak intensities as a function of electron irradiation in the dose range 10-6 to 10-2 C mm-2. The surface analysis resu...

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

Characterization and performances of a monitoring ionization chamber dedicated to IBA-universal irradiation head for Pencil Beam Scanning

Energy Technology Data Exchange (ETDEWEB)

Courtois, C. [LPC (IN2P3-ENSICAEN-UNICAEN), 6 Boulevard Maréchal Juin, 14050 Caen (France); Boissonnat, G., E-mail: boissonnat@lpccaen.in2p3.fr [LPC (IN2P3-ENSICAEN-UNICAEN), 6 Boulevard Maréchal Juin, 14050 Caen (France); Brusasco, C. [IBA, 3 Chemin du Cyclotron, 31348 Louvain-la-Neuve (Belgium); Colin, J.; Cussol, D.; Fontbonne, J.M. [LPC (IN2P3-ENSICAEN-UNICAEN), 6 Boulevard Maréchal Juin, 14050 Caen (France); Marchand, B.; Mertens, T.; Neuter, S. de [IBA, 3 Chemin du Cyclotron, 31348 Louvain-la-Neuve (Belgium); Peronnel, J. [LPC (IN2P3-ENSICAEN-UNICAEN), 6 Boulevard Maréchal Juin, 14050 Caen (France)

2014-02-01

Every radiotherapy center has to be equipped with real-time beam monitoring devices. In 2008, we developed an ionization chamber in collaboration with the IBA (Ion Beam Applications) company. This monitoring device called IC2/3 was developed to be used in IBA universal irradiation head for Pencil Beam Scanning (PBS). Here we present the characterization of the IC2/3 monitor in the energy and flux ranges used in protontherapy. The equipment has been tested with an IBA cyclotron able to deliver proton beams from 70 to 230 MeV. This beam monitoring device has been validated and is now installed at the Westdeutsches Protonentherapiezentrum Essen protontherapy center (WPE, Germany). The results obtained in both terms of spatial resolution and dose measurements are at least equal to the initial specifications needed for PBS purposes. The detector measures the dose with a relative uncertainty lower than 1% in the range from 0.5 Gy/min to 8 Gy/min while the spatial resolution is better than 250μm. The technology has been patented and five IC2/3 chambers were delivered to IBA. Nowadays, IBA produces the IC2/3 beam monitoring device as a part of its Proteus 235 product.

Study on the sterilization of egg white powder by irradiation

International Nuclear Information System (INIS)

Fu Lixin; Meng Lifen; Zhao Xiaonan; Xu Dechun; Hu Shaoxin; Chen Changdong; Wang Zhidong

2013-01-01

The sterilizing effect, influence on main essential nutrient and sensory qualities of egg white powder treated with 60 Co γ-ray irradiation were studied. The microorganism index of egg white powder samples treated with 4 kGy irradiation could meet the government food sanitation standard, and the sterilization rate could reach 100%. The irradiation doses from 4 to 10 kGy had little influence on egg white powder protein, crude fiber and amino acidscontent, and the sensory quality such as color, luster, and scent changed little below 6 kGy irradiation. Considering the result of this study, the optimal irradiation dose for egg white powder sterilization was 4 to 6 kGy. (authors)

Study irradiation damage by fast neutrons in Portland cement by means of ultra-sound

International Nuclear Information System (INIS)

Rosa Junior, A.A.

1988-01-01

The effect of neutron irradiation in samples of Portland cement paste was evaluated, using the resonance frequency method and pulse velocity of ultra-sound technique. The samples were divide in three groups: 1) Monitoring samples; 2) Samples to gamma heating simulation; 3) Fast neutron irradiated samples in reactor core. Santa Rita Portland cement was utilized for samples preparation with water-cement rate of 0,40 l/kg. The irradiation was performed in the research reactor IEA-R1, at IPEN-CNEN/SP, with an integrated flux of 7,2 X 10 sup(18) n/cm sup(2) (E approx. 1 Mev). The samples of group 2 were submitted to special micro-waves heat treatment-with the same number of cycles of the reactor-which allowed the detection of fast neutron radiation effects within the predominant thermal effects. (author)

Pathological study about two autopsy cases of bilateral irradiation pneumonitis induced by unilateral irradiation

International Nuclear Information System (INIS)

Yamauchi, Noriko; Tajima, Yo; Iio, Masaaki; Oshima, Takeo; Iino, Koichi.

1978-01-01

The first case is a 73-year-old man with left lung cancer. Seven days after completion of radiotherapy 7,000 rad, a chest roentgenogram showed diffuse bilateral pneumonia. The second case is a 61-year-old woman with right lung cancer and about one month after completion of radiotherapy 2,600 rad, a chest roentgenogram showed bilateral pneumonia. Pathological findings, all lobes of both lungs of these cases showed acute interstitial pneumonitis. The pathogenesis of irradiation pneumonitis is poorly understood. Several investigators thought that the pathogenesis of irradiation pneumonitis was caused by autoimmune mechanism, they carried out sero-pathological studies and demonstrated the bilateral pneumonia caused by unilateral irradiation. (author)

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.

Study On Irradiated Vietnam Java Rambutan Fruit Which Was Postharvested Treatment To Prolong The Shelflife For Export Purposes

International Nuclear Information System (INIS)

Nguyen Thuy Khanh; Nguyen Thi Ly; Doan Thi The; Cao Van Chung; Nguyen Van Phong

2014-01-01

The research - Study on irradiated Vietnam Java rambutan fruit which was postharvested treatment to prolong the shelflife for export purposes - was conducted at Research and Development Center for Radiation Technology and Southern Horticultural Research Institute for 12 months. On the one hand, the theme was to study the effects of low-dose radiation in the range (200-500 Gy) combined with two types of packaging: carton boxes and carton boxes + PE perforated cover 0.5% of the area bags. After 13 days monitoring in 13 o C, RH= 85-90% the results showed that Java rambutan fruit which was packed in carton boxes combined PE bags then irradiated at 300 Gy dose could limit the browning pericarp, dehydration through the rate of browning, browning level and the percentage of weight loss. Irradiated ramtuban also remains their pulp quality when testing the soluble solids, the titratable acidity and the ascorbic acid content. Irradiation did not affect the cell structure of pericarp and pulp by investigating the total ion leakage. On the other hand, the topics also examined the influence of some postharvest handling and low-dose radiation on Java rambutan. The results showed that pre-irradiation processing: hot water treatment at 43 o C in 6 minute, dipping in cloruacalxi 0.4% + citric acid 0.5% solution in 3 minutes, packed in carton boxes + PE bags and irradiated at 300 Gy dose capable of maintaining the quality which extends the shelflife of Java rambutan more 4 days when kept under conditions of 13 o C, RH= 85-90%. (author)

NMR studies of defects created by irradiation in metals

International Nuclear Information System (INIS)

Minier, M.; Minier, C.

1983-06-01

Nuclear Magnetic Resonance has been rarely used to study point defects created by irradiation in metals. Information obtained in this field using N.M.R. are shown. Some results are also described: characterization of migrating defects in electron irradiated copper; mobility of the complex interstitial-impurity in Al with 150 ppm of chromium; interstitial structure in irradiated aluminum and autodiffusion in metals [fr

Surface study of irradiated sapphires from Phrae Province, Thailand using AFM

Science.gov (United States)

Monarumit, N.; Jivanantaka, P.; Mogmued, J.; Lhuaamporn, T.; Satitkune, S.

2017-09-01

The irradiation is one of the gemstone enhancements for improving the gem quality. Typically, there are many varieties of irradiated gemstones in the gem market such as diamond, topaz, and sapphire. However, it is hard to identify the gemstones before and after irradiation. The aim of this study is to analyze the surface morphology for classifying the pristine and irradiated sapphires using atomic force microscope (AFM). In this study, the sapphire samples were collected from Phrae Province, Thailand. The samples were irradiated by high energy electron beam for a dose of ionizing radiation at 40,000 kGy. As the results, the surface morphology of pristine sapphires shows regular atomic arrangement, whereas, the surface morphology of irradiated sapphires shows the nano-channel observed by the 2D and 3D AFM images. The atomic step height and root mean square roughness have changed after irradiation due to the micro-structural defect on the sapphire surface. Therefore, this study is a frontier application for sapphire identification before and after irradiation.

Spectroscopic study of gamma irradiated bovine hemoglobin

International Nuclear Information System (INIS)

Maghraby, Ahmed Mohamed; Ali, Maha Anwar

2007-01-01

In the present study, the effects of ionizing radiation of Cs-137 and Co-60 from 4.95 to 743.14 Gy and from 40 Gy to 300 kGy, respectively, on some bovine hemoglobin characteristics were studied. Such an effect was evaluated using electron paramagnetic resonance (EPR) spectroscopy, and infra-red (IR) spectroscopy. Bovine hemoglobin EPR spectra were recorded and analyzed before and after irradiation and changes were explained in detail. IR spectra of unirradiated and irradiated Bovine hemoglobin were recorded and analyzed also. It was found that ionizing radiation may lead to the increase of free radicals production, the decrease in α-helices contents, which reflects the degradation of hemoglobin molecular structure, or at least its incomplete performance. Results also show that the combined application of EPR and FTIR spectroscopy is a powerful tool for determining structural modification of bovine hemoglobin samples exposed to gamma irradiation

Study on irradiation preservation of frozen shelled shrimps

International Nuclear Information System (INIS)

Liu Chunquan; Zhu Jiating; Zhao Yongfu; Yu Gang; Zhang Weidong; Jin Yudong; Ji Ping

2004-01-01

The effect of irradiaiton preservation of frozen shelled shrimps for export was studied. The microbial indexd, nutritional ingredient, physico-chemical index for irradiation frozen shelled shrimps were detected. The results showed that 3-5 kGy irradiation dose could kill more than 99% of all kinds of microorganisms in frozen shelled shrimps, the content of most amino acids in shelled shrimps increased, after being irradiated by 1-9 kGy dose, the total amino acids had been obvisouly higher than CK, the increased range was 0.33%-24.6%, the content of the total volatile basic nitrogen (TVBN) decreased. Compared with the CK, the content of the heavy metal elements etc had no obvious change, the presrvation duration of irradiated shelled shrimp was twelve months longer than that of CK when storage temperature was under -7 degree C soft frozen, Compared with -18 degree C the effect of irradiation preservation had no obvious change. (authors)

Studies on apple preservation by 60 -gamma irradiation

International Nuclear Information System (INIS)

Wang Chuanyao; Jiang Mengyue; Gao Meixu

1992-01-01

Studies on '60'Co-gamma irradiation of Golden Delicious apple have been carried out. The results showed that the optimum irradiation dosage for stored apple was ranged from 0.3-0.5 k Gy, with this dosage, the contents of vitamin c and titratalbe acidity in these apples had no significant change compared with unirradiated apples. The respiratory rate and the amount of ethylene release were decreased after irradiation. The mortality of the verticillate pathogenic fungi was 97% at the dose of 0.5 k Gy

Uses of AES and RGA to study neutron-irradiation-enhanced segregation to internal surfaces

International Nuclear Information System (INIS)

Gessel, G.R.; White, C.L.

1980-01-01

The high flux of point defects to sinks during neutron irradiation can result in segregation of impurity or alloy additions to metals. Such segregants can be preexisting or produced by neutron-induced transmutations. This segregation is known to strongly influence swelling and mechanical properties. Over a period of years, facilities have been developed at ORNL incorporating AES and RGA to examine irradiated materials. Capabilities of this system include in situ tensile fracture at elevated temperatures under ultrahigh vacuum 10 -10 torr and helium release monitoring. AES and normal incidence inert ion sputtering are exploited to examine segregation at the fracture surface and chemical gradients near the surface

Studies on the safety and consumer acceptance of gamma irradiated meats

Energy Technology Data Exchange (ETDEWEB)

Kang, Il Jun [Hallym University, Kangwon (Korea); Lee, Cherl Ho [Korea University, Seoul (Korea); Kim, Jung Hee [Seoul Women' s University, Seoul (Korea)

1999-04-01

Gamma irradiation was applied to beefs (0-5 kGy) and porks (0-30 kGy) for evaluation of their possible genotoxicity, acute toxicity and four-week oral toxicity. The results were negative in the bacterial reversion assay with S. typhimurium TA98, TA100, TA1535, TA1537. Clastogenic effects of the irradiated samples tested were not shown in vivo mouse micronucleus assay. In an acute toxicity test, the maximal dose of 5,000 mg/kg did not change any toxic parameter examined in this study. In four-week oral toxicity study, no significant differences were found between the control and treatment groups. In the study of rat hepatocarcinogenesis, the consumption of gamma irradiated beef and pork not only does not affect the formation of lipid peroxide and membrane stability but also has a possibility to inhibit hepatocarcinogenesis. Also, the consumption of {gamma} - irradiated beef and pork does not affect antioxidative defense system. In the study of the biological safety of korean red pepper, no difference was found on microbial growth between pepper extract alone or irradiated pepper extract. In the preservation study of korean traditional rice-cake(garedok), irradiation dose below 10kGy had no influence on typical sensory characteristics. The shelf-life in rice-cakes with different conditions was the longest on 10kGy treatment than 5kGy. In investigation of the consumer attitude toward irradiated foods, the main reason for the concern about irradiated foods is that compounds in the products formed by irradiation. Therefore, regulatory authorities must be encouraged to permit the sale of irradiated items when wholesomeness is established. (author). 94 refs.,31 figs., 62 tabs.

The Advanced Test Reactor Irradiation Facilities and Capabilities

International Nuclear Information System (INIS)

S. Blaine Grover; Raymond V. Furstenau

2007-01-01

The Advanced Test Reactor (ATR) is one of the world's premiere test reactors for performing long term, high flux, and/or large volume irradiation test programs. The ATR is a very versatile facility with a wide variety of experimental test capabilities for providing the environment needed in an irradiation experiment. These different capabilities include passive sealed capsule experiments, instrumented and/or temperature-controlled experiments, and pressurized water loop experiment facilities. The ATR has enhanced capabilities in experiment monitoring and control systems for instrumented and/or temperature controlled experiments. The control systems utilize feedback from thermocouples in the experiment to provide a custom blended flowing inert gas mixture to control the temperature in the experiments. Monitoring systems have also been utilized on the exhaust gas lines from the experiment to monitor different parameters, such as fission gases for fuel experiments, during irradiation. ATR's unique control system provides axial flux profiles in the experiments, unperturbed by axially positioned control components, throughout each reactor operating cycle and over the duration of test programs requiring many years of irradiation. The ATR irradiation positions vary in diameter from 1.6 cm (0.625 inches) to 12.7 cm (5.0 inches) over an active core length of 122 cm (48.0 inches). Thermal and fast neutron fluxes can be adjusted radially across the core depending on the needs of individual test programs. This paper will discuss the different irradiation capabilities available and the cost/benefit issues related to each capability. Examples of different experiments will also be discussed to demonstrate the use of the capabilities and facilities at ATR for performing irradiation experiments

Study of the optical monitoring system of the scintillating crystal involved in the electromagnetic calorimeter of CMS experiment

International Nuclear Information System (INIS)

Geleoc, M.

1998-01-01

The prospect of the experimental discovery of the Higgs boson is one of the motivations to build the large hadron collider (LHC). Proton beams will collide and the emitted particles will be detected by ATLAS and CMS equipment. In each detector the electromagnetic calorimeter will allow the characterisation of the 2 photons coming from one of the disintegration channels of the Higgs boson. CMS collaboration has chosen an homogeneous calorimeter fitted with PbWO 4 crystals. Each crystal with its photodetector and its electronic device forms one detection channel. The resolution of the detection channels should not deteriorate all along the operating time. The optical monitoring system of the crystals logs then controls the response of each detection channel in order to allow an accurate calibration of the calorimeter. The optical properties, the resistance to irradiation of PbWO 4 crystals and the modelling of light collection are investigated in this work. The description of the different components of the optical monitoring system highlights the technical difficulties we had to challenge. An experimental testing bench has been set up to study the coupling between the scintillation signal and the signal that feeds the monitoring system, this coupling has been studied under irradiation in the conditions of CMS operating. (A.C.)

Performance studies under high irradiation of resistive bulk-micromegas chambers at the CERN Gamma Irradiation Facility

CERN Document Server

Sidiropoulou, Ourania; Bortfeldt, J; Farina, E; Iengo, P; Longo, L; Sidiropoulou, O; Wotschack, J

2017-01-01

Radiation studies on several resistive bulk-Micromegas chambers produced at CERN will be viewed in this document. Two resistive bulk-Micromegas chambers have been installed at the CERN Gamma Irradiation Facility (GIF++) exposed to an intense gamma irradiation with the aim of evaluating the detector behaviour under high irradiation and carrying out a long-term age- ing study. The chambers under study have an active area of 10 x 10 cm 2 , a strip pitch of 400 m m , an ampli- fication gap of 128 m m , and a drift gap of 5 mm. The results on the detector performance as a function of the photon flux up to 44 MHz/cm 2 will be shown as well as the ageing properties as function of the integrated charge and the current intensity and its stability with time. In addition, the results of the efficiency measurements before, during, and after the irradiation will also be presented as a function of the amplification voltage at which the chambers are operated.

Stereophotogrammetric study of surface topography in ion irradiated silver

International Nuclear Information System (INIS)

Sokolov, V.N.; Fayazov, I.M.

1993-01-01

The irradiated surface topography of polycrystalline silver was studied using the stereophotogrammetric method. The surface of silver was irradiated with 30 keV argon ions at variation for the ion incidence angle in interval of 0-80 deg relative to a surface normal. The influence of the inclination angle of the sample in the SEM on the cone shape of a SEM-picture of the irradiated surface is discussed. The parameters of cones on the irradiated surface of silver were measured by the SEM-stereomethod. The measurements of the sample section perpendicular to the incidence plane are also carried out

Preliminary study on sterilization effect of irradiation on dry vegetable

International Nuclear Information System (INIS)

Zhai Jianqing; Bao Jianzhong; Cao Hong; Wang Jinrong; Chen Xiulan

2004-01-01

The number of surviving germs relationship to irradiation dose for several species dry vegetable was studied, and the original value D 10 of the dry vegetable was given. The value will provide a theoretical reference to ascertain the appropriate irradiation dose in the irradiation process of the dry vegetable

Irradiation Testing of TRISO-Coated Particle Fuel in Korea

International Nuclear Information System (INIS)

Kim, Bong Goo; Yeo, Sunghwan; Jeong, Kyung-Chai; Eom, Sung-Ho; Kim, Yeon-Ku; Kim, Woong Ki; Lee, Young Woo; Cho, Moon Sung; Kim, Yong Wan

2014-01-01

In Korea, coated particle fuel is being developed to support development of a VHTR. At the end of March 2014, the first irradiation test in HANARO at KAERI to demonstrate and qualify TRISO-coated particle fuel for use in a VHTR was terminated. This experiment was conducted in an inert gas atmosphere without on-line temperature monitoring and control, or on-line fission product monitoring of the sweep gas. The irradiation device contained two test rods, one has nine fuel compacts and the other five compacts and eight graphite specimens. Each compact contains about 260 TRISO-coated particles. The duration of irradiation testing at HANARO was about 135 full power days from last August 2013. The maximum average power per particle was about 165 mW/particle. The calculated peak burnup of the TRISO-coated fuel was a little less than 4 atom percent. Post-irradiation examination is being carried out at KAERI’s Irradiated Material Examination Facility beginning in September of 2014. This paper describes characteristics of coated particle fuel, the design of the test rod and irradiation device for this coated particle fuel, and discusses the technical results of irradiation testing at HANARO. (author)

Irradiation creep of candidate materials for advanced nuclear plants

Energy Technology Data Exchange (ETDEWEB)

Chen, J., E-mail: jiachao.chen@psi.ch; Jung, P.; Hoffelner, W.

2013-10-15

In the present paper, irradiation creep results of an intermetallic TiAl alloy and two ferritic oxide dispersion strengthened (ODS) steels are summarized. In situ irradiation creep measurements were performed using homogeneous implantation with α- and p-particles to maximum doses of 0.8 dpa at displacement damage rates of 2–8 × 10{sup −6} dpa/s. The strains of miniaturized flat dog-bone specimens were monitored under uniaxial tensile stresses ranging from 20 to 400 MPa at temperatures of 573, 673 and 773 K, respectively. The effects of material composition, ODS particle size, and bombarding particle on the irradiation creep compliance was studied and results are compared to literature data. Evolution of microstructure during helium implantation was investigated in detail by TEM and is discussed with respect to irradiation creep models.

Irradiation testing of coated particle fuel at Hanaro

International Nuclear Information System (INIS)

Goo Kim, Bong; Sung Cho, Moo; Kim, Yong Wan

2014-01-01

TRISO-coated particle fuel is developing to support development of VHTR in Korea. From August 2013, the first irradiation testing of coated particle fuel was begun to demonstrate and qualify TRISO fuel for use in VHTR in the HANARO at KAERI. This experiment is currently undergoing under the atmosphere of a mixed inert gas without on-line temperature monitoring and control combined with on-line fission product monitoring of the sweep gas. The irradiation device contains two test rods, one contains nine fuel compacts and the other five compacts and eight graphite specimens. Each compact has 263 coated particles. After a peak burn-up of about 4 at% and a peak fast neutron fluence of about 1.7 x 10 21 n/cm 2 , PIE will be carried out at KAERI's Irradiated Material Examination Facility. This paper is described characteristics of coated particle fuel, the design of test rod and irradiation device for coated particle fuel, discusses the technical results for irradiation testing at HANARO. (authors)

A history of studies on safety of irradiated foods

International Nuclear Information System (INIS)

Miyahara, Makoto

2003-01-01

This report explained a history of studies on safety of irradiated foods in the United States. The army of USA had begun an experiment of irradiated foods in 1953. The toxic tests consisted of three phase, the phase I (1954 to 1959), phase II (1956 to 1965) and phase III (1971 to 1978). In the phase I, the short period toxic tests (90days) of 54 kinds of foods were carried out using high and low irradiation. The Swift and Company Laboratories reported detailed animal tests of 2685 albino rat, chickens and human. The animal tests showed many kinds of nutrition disorder, but the human test no problem. On phase II, 22 kinds of foods were tested for long period using rat, dog and mouse. Dog showed many kinds of symptom, for example, low birthrate, short life time, low growth rate, increasing spleen weight and thyroid disease. On phase III, two companies carried out the toxic test and Ralston Purina Company report is only data to be used now. Atomic Energy Commission (AEC) (1960 to 1970), Department of Commerce (1965 to 1976) and Department of Agriculture (1961 to 1966) studied safety of irradiated foods. Food and Drug Administration (FDA) determined that the irradiated foods belonged to under the category of food additive in 1958. FDA tests safety of irradiated foods using the determination tree and permitted many kinds of irradiated foods. (S.Y.)

Physic-chemical Study of Starch Extracted from Irradiated Corn Flour

International Nuclear Information System (INIS)

Pozo Sanchez, R. del; Alvarez Gil, M.

1986-01-01

The effects of gamma irradiation on starch extracted from irradiated samples of corn flour were studied in the range 0,6 kGy-1,0 kGy. Amylographic properties, solubility and swelling powder of starch samples were determined immediately after irradiation and at 75 days storage at environment conditions (16 0 C-31 0 C, 55%-97% H.R.). Diffraction patterns of crystalline starch were also obtained by X-rays. Gelatinization temperature, swelling powder and diffraction patterns did not change upon irradiation, but a decrease in viscosity and an increase in starch solubility were observed within the dose-range and storage time studied. (author)

Study on irradiation treatment to drunk crab

International Nuclear Information System (INIS)

Cao Hong; Chen Xiulan; Zhai Jianqing; Bao Jianzhong; Wang Jinrong

2002-01-01

For guaranteeing the quality of irradiated drunk crab, manufacture method of the dosimeter, sample setting and taking position, irradiation time, asymmetry degree of irradiation dose, contrast of the dosimeter are discussed and some reference datum to commercialization of drunk crab's irradiation are provided

Development status of irradiation devices and instrumentation for material and nuclear fuel irradiation tests in HANARO

Energy Technology Data Exchange (ETDEWEB)

Kim, Bong Goo; Sohn, Jae Min; Choo, Kee Nam [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

2010-04-15

The High flux Advanced Neutron Application ReactOr (HANARO), an open-tank-in-pool type reactor, is one of the multi-purpose research reactors in the world. Since the commencement of HANARO's operations in 1995, a significant number of experimental facilities have been developed and installed at HANARO, and continued efforts to develop more facilities are in progress. Owing to the stable operation of the reactor and its frequent utilization, more experimental facilities are being continuously added to satisfy various fields of study and diverse applications. The irradiation testing equipment for nuclear fuels and materials at HANARO can be classified into capsules and the Fuel Test Loop (FTL). Capsules for irradiation tests of nuclear fuels in HANARO have been developed for use under the dry conditions of the coolant and materials at HANARO and are now successfully utilized to perform irradiation tests. The FTL can be used to conduct irradiation testing of a nuclear fuel under the operating conditions of commercial nuclear power plants. During irradiation tests conducted using these capsules in HANARO, instruments such as the thermocouple, Linear Variable Differential Transformer (LVDT), small heater, Fluence Monitor (F/M) and Self-Powered Neutron Detector (SPND) are used to measure various characteristics of the nuclear fuel and irradiated material. This paper describes not only the status of HANARO and the status and perspective of irradiation devices and instrumentation for carrying out nuclear fuel and material tests in HANARO but also some results from instrumentation during irradiation tests

Preliminary study on irradiation breeding of ornamental lotus

International Nuclear Information System (INIS)

Chen Xiulan; Bao Jianzhong; Liu Chungui; Cao Hong; Zhai Jianqing

2004-01-01

The effects of γ-ray irradiation on seeds and stems of ornamental lotus were studied. The results show that the mutation rate of seeds is higher than that of stems, and 30-60 Gy is the appropriate irradiation dose. The varieties with red or multi-color flower are more mutable than those with white flower. Two varieties were selected

In vivo skin leptin modulation after 14 MeV neutron irradiation: a molecular and FT-IR spectroscopic study

Energy Technology Data Exchange (ETDEWEB)

Cestelli Guidi, M.; Mirri, C.; Marcelli, A. [Laboratori Nazionali di Frascati - INFN, Frascati, Rome (Italy); Fratini, E.; Amendola, R. [ENEA, UT BIORAD-RAB, Rome (Italy); Licursi, V.; Negri, R. [Universita La Sapienza, Dip. Biologia e Biotecnologie ' ' Charles Darwin' ' , Rome (Italy)

2012-09-15

This paper discusses gene expression changes in the skin of mice treated by monoenergetic 14 MeV neutron irradiation and the possibility of monitoring the resultant lipid depletion (cross-validated by functional genomic analysis) as a marker of radiation exposure by high-resolution FT-IR (Fourier transform infrared) imaging spectroscopy. The irradiation was performed at the ENEA Frascati Neutron Generator (FNG), which is specifically dedicated to biological samples. FNG is a linear electrostatic accelerator that produces up to 1.0 x 10{sup 11} 14-MeV neutrons per second via the D-T nuclear reaction. The functional genomic approach was applied to four animals for each experimental condition (unirradiated, 0.2 Gy irradiation, or 1 Gy irradiation) 6 hours or 24 hours after exposure. Coregulation of a subclass of keratin and keratin-associated protein genes that are physically clustered in the mouse genome and functionally related to skin and hair follicle proliferation and differentiation was observed. Most of these genes are transiently upregulated at 6 h after the delivery of the lower dose delivered, and drastically downregulated at 24 h after the delivery of the dose of 1 Gy. In contrast, the gene coding for the leptin protein was consistently upregulated upon irradiation with both doses. Leptin is a key protein that regulates lipid accumulation in tissues, and its absence provokes obesity. The tissue analysis was performed by monitoring the accumulation and the distribution of skin lipids using FT-IR imaging spectroscopy. The overall picture indicates the differential modulation of key genes during epidermis homeostasis that leads to the activation of a self-renewal process at low doses of irradiation. (orig.)

In vivo skin leptin modulation after 14 MeV neutron irradiation: a molecular and FT-IR spectroscopic study.

Science.gov (United States)

Cestelli Guidi, M; Mirri, C; Fratini, E; Licursi, V; Negri, R; Marcelli, A; Amendola, R

2012-09-01

This paper discusses gene expression changes in the skin of mice treated by monoenergetic 14 MeV neutron irradiation and the possibility of monitoring the resultant lipid depletion (cross-validated by functional genomic analysis) as a marker of radiation exposure by high-resolution FT-IR (Fourier transform infrared) imaging spectroscopy. The irradiation was performed at the ENEA Frascati Neutron Generator (FNG), which is specifically dedicated to biological samples. FNG is a linear electrostatic accelerator that produces up to 1.0 × 10(11) 14-MeV neutrons per second via the D-T nuclear reaction. The functional genomic approach was applied to four animals for each experimental condition (unirradiated, 0.2 Gy irradiation, or 1 Gy irradiation) 6 hours or 24 hours after exposure. Coregulation of a subclass of keratin and keratin-associated protein genes that are physically clustered in the mouse genome and functionally related to skin and hair follicle proliferation and differentiation was observed. Most of these genes are transiently upregulated at 6 h after the delivery of the lower dose delivered, and drastically downregulated at 24 h after the delivery of the dose of 1 Gy. In contrast, the gene coding for the leptin protein was consistently upregulated upon irradiation with both doses. Leptin is a key protein that regulates lipid accumulation in tissues, and its absence provokes obesity. The tissue analysis was performed by monitoring the accumulation and the distribution of skin lipids using FT-IR imaging spectroscopy. The overall picture indicates the differential modulation of key genes during epidermis homeostasis that leads to the activation of a self-renewal process at low doses of irradiation.

Real-time beam monitoring in scanned proton therapy

Science.gov (United States)

Klimpki, G.; Eichin, M.; Bula, C.; Rechsteiner, U.; Psoroulas, S.; Weber, D. C.; Lomax, A.; Meer, D.

2018-05-01

When treating cancerous tissues with protons beams, many centers make use of a step-and-shoot irradiation technique, in which the beam is steered to discrete grid points in the tumor volume. For safety reasons, the irradiation is supervised by an independent monitoring system validating cyclically that the correct amount of protons has been delivered to the correct position in the patient. Whenever unacceptable inaccuracies are detected, the irradiation can be interrupted to reinforce a high degree of radiation protection. At the Paul Scherrer Institute, we plan to irradiate tumors continuously. By giving up the idea of discrete grid points, we aim to be faster and more flexible in the irradiation. But the increase in speed and dynamics necessitates a highly responsive monitoring system to guarantee the same level of patient safety as for conventional step-and-shoot irradiations. Hence, we developed and implemented real-time monitoring of the proton beam current and position. As such, we read out diagnostic devices with 100 kHz and compare their signals against safety tolerances in an FPGA. In this paper, we report on necessary software and firmware enhancements of our control system and test their functionality based on three exemplary error scenarios. We demonstrate successful implementation of real-time beam monitoring and, consequently, compliance with international patient safety regulations.

Studies on Post-Irradiation DNA Degradation in Micrococcus Radiodurans, Strain RII51

DEFF Research Database (Denmark)

Auda, H.; Emborg, C.

1973-01-01

The influence of irradiation condition on post-irradiation DNA degradation was studied in a radiation resistant mutant of M. radiodurans, strain ${\\rm R}_{{\\rm II}}5$. After irradiation with 1 Mrad or higher more DNA is degraded in cells irradiated in wet condition than in cells irradiated with t...

Satellite estimation of surface spectral ultraviolet irradiance using OMI data in East Asia

Science.gov (United States)

Lee, H.; Kim, J.; Jeong, U.

2017-12-01

Due to a strong influence to the human health and ecosystem environment, continuous monitoring of the surface ultraviolet (UV) irradiance is important nowadays. The amount of UVA (320-400 nm) and UVB (290-320 nm) radiation at the Earth surface depends on the extent of Rayleigh scattering by atmospheric gas molecules, the radiative absorption by ozone, radiative scattering by clouds, and both absorption and scattering by airborne aerosols. Thus advanced consideration of these factors is the essential part to establish the process of UV irradiance estimation. Also UV index (UVI) is a simple parameter to show the strength of surface UV irradiance, therefore UVI has been widely utilized for the purpose of UV monitoring. In this study, we estimate surface UV irradiance at East Asia using realistic input based on OMI Total Ozone and reflectivity, and then validate this estimated comparing to UV irradiance from World Ozone and Ultraviolet Radiation Data Centre (WOUDC) data. In this work, we also try to develop our own retrieval algorithm for better estimation of surface irradiance. We use the Vector Linearized Discrete Ordinate Radiative Transfer (VLIDORT) model version 2.6 for our UV irradiance calculation. The input to the VLIDORT radiative transfer calculations are the total ozone column (TOMS V7 climatology), the surface albedo (Herman and Celarier, 1997) and the cloud optical depth. Based on these, the UV irradiance is calculated based on look-up table (LUT) approach. To correct absorbing aerosol, UV irradiance algorithm added climatological aerosol information (Arola et al., 2009). The further study, we analyze the comprehensive uncertainty analysis based on LUT and all input parameters.

S3 targets monitoring with an electron gun

Science.gov (United States)

Kallunkathariyil, J.; Stodel, Ch.; Marry, C.; Frémont, G.; Bastin, B.; Piot, J.; Clément, E.; Le Moal, S.; Morel, V.; Thomas, J.-C.; Kamalou, O.; Spitaëls, C.; Savajols, H.; Vostinar, M.; Pellemoine, F.; Mittig, W.

2018-05-01

The monitoring of targets under irradiation was investigated using a 20 keV electron beam. An integrated and automated electron beam deflection was developed allowing a monitoring over the whole surface of target materials. Thus, local defects could be identified on-line during an experiment performed at GANIL involving different materials irradiated with a focused krypton beam at 10.5 MeV/u. Performances of this target monitoring system are presented in this paper.

Study on innocent irradiation treatment of Trichinella spiralis pork

International Nuclear Information System (INIS)

Zhao Guang; Guo Anxi; Xu Zhaomei

1992-01-01

The effects of 60 Co gamma rays on pork Trichinella spiralis and nutritional hygiene evaluation of irradiated Trichinella spiralis pork were studied by using animal infestation test and artificial gastric juice digestion method. The results showed that when mouse was infested by Trichinella spiralis pork irradiated with a dose of 0.04 kGy, the number of the second generation larvae and the parasitism in the muscle were reduced. 0.08 kGy irradiation could render the intestine Trichinella spiralis sterile. 0.1 kGy blocked the growth of Trichinella spiralis, which were excreted from the body four days after infestation. 0.2-0.8 kGy irradiation could severely block the growth of Trichinella spiralis, which were excreted completely from the body within forth-eight hours when irradiated with 7 kGy and 8 kGy, the Trichinella spiralis body was not found in the intestine within twenty-four hours. 0.3 kGy and 1 kGy irradiation had no harmful effect on nutrition and wholesomeness of Trichinella spiralis pork. Innocent irradiation treatment of Trichinella spiralis pork is practicable, and the lowest dose should be 0.3 kGy

SORCE and Future Satellite Observations of Solar Irradiance

Science.gov (United States)

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

2003-01-01

With solar activity just passing the maximum of cycle 23, SORCE is beginning a 5 year mission to measure total solar irradiance (TSI) with unprecedented accuracy using phase-sensitive detection, and to measure spectral solar irradiance (SSI) with unprecedented spectral coverage, from 1 to 2000 nm. The new Total Irradiance Monitor (TIM) has 4 active cavity radiometers, any one of which can be used as a fixed-temperature reference against any other that is exposed to the Sun via a shutter that cycles at a rate designed to minimize noise at the shutter frequency. The new Spectral Irradiance Monitor (SIM) is a dual Fery prism spectrometer that can employ either prism as a monochromatic source on the other prism, thus monitoring its transmission during the mission lifetime. Either prism can measure SSI from 200 to 2000 nm, employing the same phase-sensitive electrical substitution strategy as TIM. SORCE also carries dual SOLSTICE instruments to cover the spectral range 100-320 nm, similar to the instruments onboard UARS, and also an XUV Photometer System (XPS) similar to that on TIMED. SSI has now been added to TSI as a requirement of EOS and NPOESS, because different spectral components drive different components of the climate system - UV into upper atmosphere and stratospheric ozone, IR into tropospheric water vapor and clouds, and Visible into the oceans and biosphere. Succeeding satellite missions being planned for 2006 and 2011 will continue to monitor these critical solar variables.

Prospective study of nutritional support during pelvic irradiation

International Nuclear Information System (INIS)

Kinsella, T.J.; Malcolm, A.W.; Bothe, A. Jr.; Valerio, D.; Blackburn, G.L.

1981-01-01

A prospective study of nutritional support during pelvic irradiation was carried out in 32 patients with a primary pelvic malignancy and prior weight loss. Both curative and palliative patients were eligible for the study. Seventeen patients were randomized to receive intravenous hyperalimentation (IVH) and fifteen patients served as controls who were maintained on their regular diet. Patients were stratified by percent body weight loss. Tolerance to therapy was assessed by evaluation of functional status and by using nutritional parameters of body weight change, change in serum protein levels, and response to delayed hypersensitivity skin tests. The curative IVH group tolerated therapy well by both functional and nutritional measurements. All curative IVH patients completed the planned radiation therapy without a treatment break and were fully active following treatment. Patients gained an average of 4.0 kg body weight during irradiation, which was significantly different from the curative control patients. They demonstrated a significant increase in serum transferrin reflecting an improvement in visceral protein. In addition, all showed a positive response to delayed hypersensitivity skin tests at the completion of irradiation. The palliative IVH patients often did poorly because of progression of disease and demonstrated only an elevation of serum transferrin during treatment. The results in the curative IVH group suggest a potential adjunctive role for intravenous hyperalimentation in the malnourished cancer patient undergoing pelvic irradiation. Clearly, further study of nutritional support during pelvic irradiation is needed using curative patients with a single tumor type and significant prior weight loss

In vitro study of morphological and chemical modification threshold of bovine dental enamel irradiated by the holmium laser

International Nuclear Information System (INIS)

Eduardo, Patricia Lerro de Paula

2001-01-01

The aim of this study is to investigate the Ho:YLF laser effects on the dental enamel surface with regards to its morphology, thermal variations during its irradiation in the pulp chamber and its increased resistance to demineralization through quantitative analysis of calcium and phosphorous atoms reactive concentrations in samples. Twenty samples of bovine enamel were used and divided in four groups: control - acidulated phosphate fluoride (APF) application followed by demineralization treatment with lactic acid; irradiation with Ho:YLF laser (100 J/cm 2 ) followed by APF topic application and demineralization treatment with lactic acid; irradiation with Ho:YLF laser (350 J/cm 2 ) followed by APF topic application and demineralization treatment with lactic acid: and irradiation with Ho:YLF laser ( 450 J/cm 2 ) followed by APF topic application and demineralization treatment with lactic acid. Ali samples were quantified according to their calcium and phosphorous atoms relative concentrations before and after the treatments above. X-Ray fluorescence spectrochemical analysis and scanning electron microscopy were carried out. It was observed an increase on the calcium and phosphorous atoms concentration ratio and therefore the enamel demineralization reduction as a result of the lactic acid treatment in the samples irradiated with the holmium laser followed by the APF application. In order to evaluate the feasibility of this study for clinical purposes, morphological changes caused by the holmium laser irradiation were analyzed. Such modifications were characterized by melted and re-solidified regions of the enamel with consequent changes on its permeability and solubility. Temperature changes of ten human pre-molars teeth irradiated with 350 J/cm 2 and 450 J/cm 2 were also monitored in the pulp chamber in real time. Temperature increases over 4,20 C did not occur. The results obtained from this study along with the results from previous researches developed at

Study on identification of irradiated food containing cellulose by ESR

International Nuclear Information System (INIS)

Wan Xiaojuan; Dou Daying; Xu Gang; Jiao Zheng; Wang Jia; Zheng Jianfei; Jiao Zheng; Wu Minghong; Ding Guoji

2008-01-01

The fast development and application of food irradiation technology signify the necessity and urgency to research on effective detection method for irradiated food. In this paper, we report a preliminary study in this area with dried chili powder, peanuts and strawberry seeds. The food samples were irradiated to 0.5, 1.0, 3.0, 5.0 and 10.0 kGy by 60 Co gamma rays. The relation between ESR intensity and irradiation dose, and correlation R 2 , were studied. The results showed that the ESR signal intensity is positively related with the dose. ESR intensity of the strawberry increased the slowest with the dose, and the chili powder had the most accurate calculation. Accurate dose-effect curves, however, require repeating tests and further studies are needed to verify the ESR results. (authors)

An ESR study of radicals induced in irradiated fresh mango

International Nuclear Information System (INIS)

Kikuchi, Masahiro; Hussain, Mohammed S.; Morishita, Norio; Kobayashi, Yasuhiko; Ukai, Mitsuko; Shimoyama, Yuhei

2009-01-01

An electron spin resonance (ESR) spectroscopic study was performed on the radicals induced irradiated fresh mangoes. Fresh Philippine mangoes were irradiated by the γ-rays, lyophilized and powdered. The ESR spectrum of the dry specimen showed a strong main peak at g=2.004 and a pair of peaks at both magnetic fields of the main peak. The main peak detected from flesh and skin specimens faded away in a few days after the irradiation. On the other hand, the side peaks showed a well-defined dose response even 9 days after the irradiation. The side-peak is a useful mean to define the irradiation on fresh mangoes. (author)

Determination of burn-up of irradiated nuclear fuels using mass spectrometry

International Nuclear Information System (INIS)

Jagadish Kumar, S.; Telmore, V.M.; Shah, R.V.; Sasi Bhushan, K.; Paul, Sumana; Kumar, Pranaw; Rao, Radhika M.; Jaison, P.G.

2017-01-01

Burn-up defined as the atom percent fission, is a vital parameter used for assessing the performance of nuclear fuel during its irradiation in the reactor. Accurate data on the actinide isotopes are also essential for the reliable accountability of nuclear materials and for nuclear safeguards. Both destructive and non-destructive methods are employed in the post-irradiation analysis for the burn-up measurements. Though non-destructive methods are preferred from the point view of remote handling of irradiated fuels with high radioactivity, they do not provide the high accuracy as achieved by the chemical analysis methods. Thus destructive radiochemical and chemical analyses are still the established reference methods for accurate and reliable burn-up determination of irradiated nuclear fuels. In the destructive method, burn-up of irradiated nuclear fuel is determined by correlating the amount of a fission product formed during irradiation with that of heavy elements. Thus the destructive experimental determination of burn-up involves the dissolution of irradiated fuel samples followed by the separation and determination of heavy elements and fission product(s) to be used as burn-up monitor(s). Another approach for the experimental determination of burn-up is based on the changes in the abundances of the heavy element isotopes. A widely accepted method for burn-up determination is based on stable "1"4"8Nd and "1"3"9La as burn-up monitors. Several properties such as non-volatility, nearly same yields for thermal fissions of "2"3"5U and "2"3"9Pu etc justifies the selection of "1"4"8Nd as a burn-up monitor

Gamma irradiation treatment of secondary sewage effluent

International Nuclear Information System (INIS)

Vajdic, A.H.

The operation and monitoring of a pilot scale Co-60 gamma irradiation unit treating secondary sewage effluent is described. The disinfecting efficiency of the unit is compared to that of an experimental 'ideal' chlorination unit and to the plant chlorination process. A cost estimate for disinfection by gamma irradiation on a full plant scale is included. (author)

Synthetic study of reactor irradiation for medical use

International Nuclear Information System (INIS)

An, Shigehiro; Furuhashi, Akira; Kanda, Keiji; Sumita, Kenji; Kakihana, Hidetake.

1978-01-01

This report is described on the results of the study on the reactor irradiation for medical use shared by the Nuclear Engineering Research Laboratory, Faculty of Engineering, University of Tokyo, and other seventeen facilities. Boron neutron-capturing therapy developed in Japan is extremely significant treating method for tumors by destroying tumor cells of encephaloma, etc. selectively. This is the synthetic study for promoting the above therapeutic method. Two existing reactors were reconstructed into the thermal neutron reactors for boron neutron-capturing therapy. The various preparatory and physical researches were made with the reconstruction, and the therapy was tried on eleven cases. Further experiments were made on the following points: (1) To promote treatment on encephaloma by boron neutron-capturing therapy. (2) To develop its application to malignant tumors other than encephaloma. (3) Animal irradiation experiments. (4) The basic experiments on the cellular level. (5) The study of remote controlled anesthesia. (6) To control irradiated dose. (7) To improve boron compounds. (8) To condense radioisotopes. (Kobatake, H.)

Using Gamma Irradiation to Modify Properties of Polysaccharides (Guar Gum)

International Nuclear Information System (INIS)

Sayed, H.

2015-01-01

Radiation processing of material is one of most recent technology used in modification of material properties. The aim of this work was to determine the effect of gamma irradiation on the Polysaccharides Viscosity and Molecular Weight, as definition of Guar Gum. Its series of glactomanene (glactos + manose). (1-2-,3). Guar Gum powder was the main material and Co-60 irradiator facility as main technique. For gamma–ray source of required doses, 2.5, 5, 7.5, 10, 20, 30, 40 and 50 kGy. Viscosity of the aqueous suspensions of irradiated Guar Gum at different concentrations (0.1–0.5%) was measured, also it measured for solutions made of irradiated powder. Results used to calculate the difference occur in molecular weight, in order to determine the irradiation effect in the material. The monitored rheological parameters showed (non-Newtonian Behavior) of the samples which processed by gamma irradiation. The decrease tendency of the viscosity by irradiation of samples under study (different concentrations) and compared with control also for irradiated powder decrease of the concentration as well has been noticed. From results evaluation concluded that the viscosity values for all studied concentrations decreased by irradiation. This aspect suggests a depolymerization phenomenon of the aqueous Guar Gum solutions. This study contributes to the knowledge of the viscoelastic properties of Guar Gum as powder or aqueous solution, with application for food, agriculture, medical products, Petroleum and construction. (author)

Color formation study of irradiated polymers by electron beam

International Nuclear Information System (INIS)

Nardi, Daniela Teves

2004-01-01

Color formation on national and commercial polymers (polymethyl methacrylate, polystyrene and polycarbonate) irradiated by electrons beam was investigated by colorimetry (CIELab), electron spectroscopy resonance (ESR), photoacoustic infrared spectroscopy (FTIR-PAS) and differential exploratory calorimetry (DSC). The heat effect on colorimetric properties was investigated after heating (110 deg C for 1 hour) of irradiated polymers at 150 kGy. The rule of oxygen in colorimetric properties of irradiated polycarbonate was investigated in the air presence and absence (p = 10 -3 mmHg). The visual aspect did not agree with colorimetric parameters only for polycarbonate. Yellow color and darkness were induced by radiation for all studied polymers varying only the intensity and behavior in function of post-irradiation time and heating. Polymethyl methacrylate and polystyrene ESR spectra showed that radicals could be responsible by yellow color centers. Wherever, in polycarbonate, color centers were not due radical species. The nature of color centers for any studied polymer was not study by FTIR-PAS because there were no changes in FTIR-PAS spectra neither in function of dose nor heating. Polycarbonate was the most radiosensible and polystyrene was the most radioresistant of all studied polymers in concern of colorimetric properties. (author)

Structural and functional changes in the intenstine of irradiated and hypothermic irradiated rats : a scanning and transmission electron microscopic study

International Nuclear Information System (INIS)

Chaudhuri, S.; Chaudhuri, Swapna; Roy, Bijon

1982-01-01

Severe destructive changes in the intestine of rats following whole body exposure to gamma rays (832 rads) were observed by light microscope, scanning and transmission electron microscope studies. Hypothermia (15deg C rectal temperature) induced prior to irradiation protected the intestinal mucosa from destruction. A simultaneous study showed that glucose absorption decreased significantly in irradiated rats, whereas it was increased in hypothermic irradiated animals. (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)

75 MeV boron ion irradiation studies on Si PIN photodiodes

Energy Technology Data Exchange (ETDEWEB)

Prabhakara Rao, Y.P.; Praveen, K.C. [Department of Studies in Physics, University of Mysore, Manasagangotri, Mysore 570006 (India); Rejeena Rani, Y. [Integrated Circuits Division, Bharat Electronics Limited, Bangalore 560013, Karnataka (India); Tripathi, Ambuj [Inter University Accelerator Centre, Aruna Asaf Ali Marg, New Delhi 110067 (India); Gnana Prakash, A.P., E-mail: gnanap@hotmail.com [Department of Studies in Physics, University of Mysore, Manasagangotri, Mysore 570006 (India)

2013-12-01

The highly sensitive silicon PIN photodiodes were fabricated to use in radiation environments. The Si PIN photodiodes are coated with 150 nm silicon dioxide (SiO{sub 2}) as anti-reflective (AR) coating. The presence of AR coating on the performance of irradiated PIN photodiodes is studied up to a total dose of 10 Mrad. The effects of 75 MeV boron (B{sup 5+}) ions and {sup 60}Co gamma radiation on the I–V, C–V and spectral responses of PIN photodiodes were studied systematically to understand the radiation tolerance of the devices. The 75 MeV B{sup 5+} irradiation results are compared with {sup 60}Co gamma irradiated results in the same dose range for 1 mm × 1 mm and 10 mm × 10 mm active area PIN photodiodes. The irradiation results show that the ion irradiated PIN photodiodes show more degradation when compared {sup 60}Co gamma irradiated devices. The irradiation results are presented in this paper and the possible mechanism behind the degradation of photodiodes is also discussed in the paper.

Monitoring PAI-1 and VEGF Levels in 6 Human Squamous Cell Carcinoma Xenografts During Fractionated Irradiation

International Nuclear Information System (INIS)

Bayer, Christine; Kielow, Achim; Schilling, Daniela; Maftei, Constantin-Alin; Zips, Daniel; Yaromina, Ala; Baumann, Michael; Molls, Michael; Multhoff, Gabriele

2012-01-01

Purpose: Previous studies have shown that the plasminogen activator inhibitor type-1 (PAI-1) and vascular endothelial growth factor (VEGF) are regulated by hypoxia and irradiation and are involved in neoangiogenesis. The aim of this study was to determine in vivo whether changes in PAI-1 and VEGF during fractionated irradiation could predict for radiation resistance. Methods and Materials: Six xenografted tumor lines from human squamous cell carcinomas (HSCC) of the head and neck were irradiated with 0, 3, 5, 10, and 15 daily fractions of 2 Gy. The PAI-1 and VEGF antigen levels in tumor lysates were determined by enzyme-linked immunosorbent assay kits. The amounts of PAI-1 and VEGF were compared with the dose to cure 50% of tumors (TCD 50 ). Colocalization of PAI-1, pimonidazole (hypoxia), CD31 (endothelium), and Hoechst 33342 (perfusion) was examined by immunofluorescence. Results: Human PAI-1 and VEGF (hVEGF) expression levels were induced by fractionated irradiation in UT-SCC-15, UT-SCC-14, and UT-SCC-5 tumors, and mouse VEGF (msVEGF) was induced only in UT-SCC-5 tumors. High hVEGF levels were significantly associated with radiation sensitivity after 5 fractions (P=.021), and high msVEGF levels were significantly associated with radiation resistance after 10 fractions (P=.007). PAI-1 staining was observed in the extracellular matrix, the cytoplasm of fibroblast-like stroma cells, and individual tumor cells at all doses of irradiation. Colocalization studies showed PAI-1 staining close to microvessels. Conclusions: These results indicate that the concentration of tumor-specific and host-specific VEGF during fractionated irradiation could provide considerably divergent information for the outcome of radiation therapy.

Dose monitoring in nuclear emergency

International Nuclear Information System (INIS)

Nan Hongjie; Yang Zhongping; Lei Xin

2012-01-01

In order to protect people from irradiation sickness and rebuild the radiation filed in nuclear emergency, personal and environmental dose need to be monitored. The application of TLD in dose monitoring is discussed in this paper. (authors)

Irradiation mucositis and oral flora

International Nuclear Information System (INIS)

Spijkervet, F.K.L.

1989-01-01

This study, which is motivated by the substantial morbidity of local signs of mucositis and generalized symptoms that result from mucositis induced by therapeutic irradiation, has the following objectives: To investigate if it is possible to prevent irradiation mucositis via oral flora elimination, and, if it is true that flora plays a role in irradiation mucositis, what fraction of the oral flora may be involved; to evaluate oral Gram-negative bacillary carriage; to investigate the possibility to eradicate Gram-negative bacilli from the oral cavity; to evaluate oral yeast carriage; to investigate the possibility to eradicate yeasts stomatitis and the 'selectivity' of elimination of flora. Two methods are described for monitoring alterations of mucositis of the oral cavity and changes in oral flora. Chlorhexidine has been tested as the commonly used prophylaxis. The effect of chlorhexidine 0.1% rinses on oral flora and mucositis has been studied in a prospective placebo controlled double blind randomized programme. The results of the influence of saliva on the antimicrobial activity of chlorhexidine and the results of selective elimination of oral flora in irradiated patients who have head and neck cancer are reported. Salivary inactivation of the topical antimicrobials used for selective elimination of oral flora has been studied and the results are reported. Finally, the objectives that have been achieved (or not) are delineated. The significance of the results of the study are discussed in terms of published information and further lines of research are suggested. (author). 559 refs.; 29 figs.; 20 tabs

Thermogravimetric study of γ-irradiated lanthanum oxalate

International Nuclear Information System (INIS)

Nayak, H.; Bhatta, D.

2000-01-01

Thermogravimetric study of La 2 (C 2 O 4 ) 3 , exposed to different doses (5.0 - 50.0 x 10 -2 MGy) of γ-rays has been carried out. Marginal effect is observed at lower doses which is prominent at higher dose (5.0 x 10 -1 MGy). The radiolytic damaged entities, generated by irradiation favours the reaction by creating new potential nucleation centres in the lattice. The solid product, La 2 O 3 formed by irradiation also acts as a heterogeneous catalyst and brings out changes in the reactivity of the solid. (author)

Economic Feasibility Study for Using Irradiation Technology in Preservation of Animalism Foods

International Nuclear Information System (INIS)

El Gameel, E.A.

2011-01-01

The present study discus the economic feasibility for the preservation animalism foods by using irradiation technology. This study has included the technical data, regression foretelling for the throughput, determination of irradiators types and radiation sources activity. This study comprises the financial analysis for the establishment animalism foods irradiation facilities (types: tote box, pallet conveyor) and the national return

Study on process control and acceptability of irradiated seasonings

International Nuclear Information System (INIS)

Chen Qixun; Xu Peishu; Chen Hao; Chen Lihua; Dong Shaobin

1993-01-01

This paper studied the process control and quality control of irradiated seasonings for commercial purposes, market test and consumers' acceptability. The results showed that the rate of relative deviation of dose was less than 2 and the uniformity was better than 1.31 and the number of microbes decreased by 3-4 orders of magnitude after treatment with 8 kGy. No pathogenic bacteria were discovered and sensory evaluation as well as quality analysis were not changed. 110 tons of irradiated seasonings have been supplied to domestic markets and stores since 1990. The statistic data of 2045 consumers investigated showed that 67% of consumers heard about food irradiation. 72% of persons and 67% of families were willing to buy irradiated seasonings. (author)

Studies of electron-beam irradiation on ethylene-styrene interpolymers

CERN Document Server

Liu, I C

2002-01-01

Electron-beam irradiation-induced structural and properties changes on ethylene-styrene interpolymers (ESI) have been studied at electron doses ranging from 0 to 200 kGy. The amounts of species generated by irradiation such as hydroxyls, hydroperoxides, carbonyls and unsaturated double bonds have been analyzed using ATR-FTIR. While the structural changes are minimal for ESI69 comprising 69 wt.% styrene regardless of the dose level, the changes for ESI40 comprising 40 wt.% styrene are dose dependent and reaches a maximum at a dose of 100 kGy. Gel permeation chromatography analysis indicates that macromolecular chain scission occurs at low irradiation dose and crosslinking dominates at high irradiation doses. The average molecular weights between crosslinks, M sub C 's, have been calculated using the Flory-Rehner equation based on data collected from solvent extraction experiments. The M sub C 's of ESI40 samples are much smaller than those of ESI69 samples. Irradiated ESI samples have higher glass transition t...

Facility effluent monitoring plan for the 327 Facility

International Nuclear Information System (INIS)

1994-11-01

The 327 Facility [Post-Irradiation Testing Laboratory] provides office and laboratory space for Pacific Northwest Laboratory (PNL) scientific and engineering staff conducting multidisciplinary research in the areas of post-irradiated fuels and structural materials. The facility is designed to accommodate the use of radioactive and hazardous materials in the conduct of these activities. This report summarizes the airborne emissions and liquid effluents and the results of the Facility Effluent Monitoring Plan (FEMP) determination for the facility. The complete monitoring plan includes characterization of effluent streams, monitoring/sampling design criteria, a description of the monitoring systems and sample analysis, and quality assurance requirements

Study on quality control of Chinese herb medicine irradiation

International Nuclear Information System (INIS)

Yang Dongqing; En Lihua; Deng Wenmin

2010-01-01

6-8 kGy γ-ray irradiation dosage treatment can reduce the bacteria, mildew effectively from 105 CFU/g to 102 CFU/g and eliminate the parasite in 4 kind of Chinese herb medicine, enhance their quality of sanitation observably. In the other hand, irradiation doesn't influence the medicinal component and therapy effect. Storage study has improved that the 4 kind of Chinese herb medicine treated by γ-ray irradiation can be preserved over one year in the room temperature with high quality of sanitation and steady medicinal component. (authors)

Study on the sterilization of egg white powder by irradiation

International Nuclear Information System (INIS)

Fu Lixin; Meng Lifen; Zhao Xiaonan; Xu Dechun; Hu Shaoxin; Chen Changdong; Pei Ying

2012-01-01

The article studied the killing microorganism result, the influence of main essential nutrient and sense organ of egg white powder by Co-60 γ-ray irradiation. The microorganism index of the egg white powder samples can meet the government food sanitation standard by 4 kGy irradiation, and the killing microorganism rare can reach 100%. The irradiation dose from 4 to 10 kGy has little influence to the egg white powder protein, crude fiber and amino acids contras ting to comparison, and the sensory quality such as color and luster, scent has little change below 6 kGy irradiation. Synthesizing the results of physical chemistry and sense organ, the optimal irradiation dose of egg white powder killing microorganism is 4 to 6 kGy. (authors)

Study on the sterilization of egg white powder by irradiation

International Nuclear Information System (INIS)

Fu Lixin; Meng Lifen; Zhao Xiaonan; Xu Dechun; Hu Shaoxin; Chen Changdong; Pei Ying

2011-01-01

The article studied the killing microorganism result, the influence of main essential nutrient and sense organ of egg white powder by Co-60 γ-ray irradiation. The microorganism index of the egg white powder samples can meet the government food 1 sanitation standard by 4 kGy irradiation, and the killing microorganism rare can reach 100%. The irradiation dose from 4 to 10 kGy has little influence to the egg white powder protein, crude fiber and amino acids contrasting to comparison, and the sensory quality such as color and luster, scent has little change below 6 kGy irradiation. Compositing the result of physical chemistry and sense organ, the optimal irradiation dose of egg white powder killing microorganism is 4 to 6 kGy. (authors)

Moessbauer study of defects in molybdenum and chromium irradiated with ions

International Nuclear Information System (INIS)

Troyan, V.A.; Bogdanov, V.V.; Ivanyushkin, E.M.; Pen'kov, Yu.P.

1980-01-01

Effects of ion irradiation of monocrystalline molybdenum and polycrystalline chromium with Co-57 impurity were studied by Moessbauer effect. Molybdenum specimens were irradiated by He + ions at accelerators with 40 keV energy. Chromium specimens were irradiated by hydrogen ions with 1.2 MeV energy up to integral 2x10 17 -2x10 19 ion/cm 2 doses. It is shown, that defect introduction into the source matrix by irradiation results in change of gamma-resonance line form and effect value. The observed effects of defect influence on spectrum parameters are discussed. It is concluded, that study of Moessbauer spectra parameters of diluted Co-57 solutions in matrices of different metals permits to determine dynamics of movement of impurity atoms and defects in metals irradiated with ions [ru

Electron microscope study of irradiated beryllium oxide; Etude au microscope electronique de l'oxyde de beryllium irradie

Energy Technology Data Exchange (ETDEWEB)

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

1965-06-01

The beryllium oxide is studied first by fractography, before and after irradiation, using sintered samples. The fractures are examined under different aspects. The higher density sintered samples, with transgranular fractures are the most interesting for a microscopic study. It is possible to mark the difference between the 'pores' left by the sintering process and the 'bubbles' of gases that can be produced by former thermal treatments. After irradiation, the grain boundaries are very much weakened. By annealing, it is possible to observe the evolution of the gases produced by the reaction (n, 2n) and (n. {alpha}) and gathered on the grain boundaries. The irradiated beryllium oxide is afterwards studied by transmission. For that, a simple method has been used: little chips of the crushed material are examined. Clusters of point defects produced by neutrons are thus detected in crystals irradiated at the three following doses: 6 x 10{sup 19}, 9 x 10{sup 19} and 2 x 10{sup 20} n{sub f} cm{sup -2} at a temperature below 100 deg. C. For the irradiation at 6 x 10{sup 19} n{sub f} cm{sup -2}, the defects are merely visible, but at 2 x l0{sup 20} n{sub f} cm{sup -2} the crystals an crowded with clusters and the Kikuchi lines have disappeared from the micro-diffraction diagrams. The evolution of the clusters into dislocation loops is studied by a series of annealings. The activation energy (0,37 eV) calculated from the annealing curves suggests that it must be interstitials that condense into dislocation loops. Samples irradiated at high temperatures (650, 900 and 1100 deg. C) are also studied. In those specimens the size of the loops is not the same as the equilibrium size obtained after out of pile annealing at the same temperature. Those former loops are more specifically studied and their Burgers vector is determined by micro-diffraction. (author) [French] L'oxyde de beryllium est d'abord etudie, par une methode fractographique, avant et apres irradiation, en

EPR spin probe investigation of irradiated wheat, rice and sunflower seeds

Energy Technology Data Exchange (ETDEWEB)

Paktas, Dilek Dadayl [Department of Physics, Faculty of Art and Science, Zonguldak Karaelmas University, 67100 Zonguldak (Turkey)]. E-mail: dadayli@karaelmas.edu.tr; Suennetcioglu, M. Maral [Department of Physics Engineering, Hacettepe University, 06532 Beytepe, Ankara (Turkey)

2007-01-15

TEMPO and 4-nitro-TEMPO spin probes were used to monitor dose-dependent changes in the EPR spectra of irradiated wheat and rice embryos and sunflower embryo parts. Rice embryos were studied in the 233-293 K temperature range using 4-nitro-TEMPO. TEMPAMINE, TEMPYO and DTBN spin probes were also studied for their applicability in the determination of irradiated seeds. All the recorded spectra were simulated, and spectral parameters and partition of the probes among various domains were determined. Despite the contribution of the signal from extracellular regions, it was possible to detect the changes in the water/lipid ratios with dose. The hydrophilic character of the probe alone was not sufficient to distinguish the different doses of irradiation. Line widths and rotational correlation times of various domains within embryo also play an important role. Partition after dehydration was another measure in the selection of the suitable probes for irradiation studies. Better results were obtained in dehydrated embryos for the probes preferring lipid bodies.

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

Economic feasibility study of potato preservation by irradiation in saudi arabia

Energy Technology Data Exchange (ETDEWEB)

Kinsara, A A; Abulfaraj, W H; Mamoon, A M; Kamal, S E [Nuclear Engineering Department, Faculty of Engineering, King Abdulaziz University, Jeddah (Saudi Arabia)

1997-12-31

Comprehensive studies were carried out to investigate the economic feasibility of the preservation of potato crop by cobalt-60 gamma irradiation sprout inhibition by potato irradiation was approved by international organization and concerned authorities in many countries. The dose level range authorized for potato sprout inhibition extends from about 80-150 Gy depending on potato variety, time of irradiation after harvest, and post irradiation storage temperature. Sprout inhibition is most effective by irradiation after harvest, and after healing of any inflicted injuries, that when the potatoes are dormant. Irradiation at the recommended doses minimizes storage losses of potatoes that are refrigerated or stored on shelves. Despite the limited data available, an attempt was made to quantify the monetary value of preserving potato by irradiation. With economy scale taken in consideration, potato preservation by irradiation is economically feasible since at the local consumption rates there will be lot of potatoes that ned storage for off season use. 5 tabs.

Study on the storage properties of irradiated ginger

International Nuclear Information System (INIS)

Wang Shoujing; Yu Zihou; Sun Shouyi; Zou Jiwan; Zhang Qizhi; Sun Hongchun; Lv Tiexin; Liu Xiaoyong

2004-01-01

The γ-ray irradiation could cause the loss of Vc during the early stage of storage, however, after 150 days' storage there were no significant differences of Vc content between irradiated and non-irradiated samples. The content of reduced sugar was increased by irradiation especially with 150 and 250 Gy. When ginger were irradiated with 250 Gy and stored at room temperature for 120 days, the content of Met and Arg decreased obviously, but the contents of other 16 amino acids were not affected. The respiration rate of irradiated ginger reached its peak at 7-9 days of storage, and from then it kept lower level for the rest storage time. The electrolyte permeability increased slightly after γ-irradiation. Irradiation with 80-400 Gy had no effects on lipid isoenzyme zymogram

Study of the stability of the tragacanto rubber irradiated

International Nuclear Information System (INIS)

Rodriguez, M.; Romero, M.; Montes de Oca, N.

2001-01-01

Presently work was studied the processing by radiations of the tragacanto rubber powdered, with ends of achieving its sterilization. For the irradiation, the envelopes were placed in aluminum containers to reason of an envelope for container. The material underwent analysis of its viscosity and microbiological tests. They got ready solutions, according to the British pharmacopoeia, starting from the material irradiated with dose of D0-0, D1-5, D2-7.5, and D3-10 kGy. The smaller than the applied doses (5kGy) it produced a variation of 72% in the viscosity of the solutions, in comparison with the rubber without irradiating. They were carried out tests of sterility to the material irradiated with inferior dose of 5 kGy, being contaminated in all the cases

Studies On Quality Criteria For Irradiated Breaded Chicken Breast Fillets

International Nuclear Information System (INIS)

HASSAN, I.M.; IBRAHIM, M.T.; MAHMOUD, A.A.; SHAMS EL DIN, N.M.M.; MOHAMMAD, M.K.

2010-01-01

Quality criteria of irradiated breaded chicken breast fillets were studied. Fresh boneless and skinless breaded chicken breast meats samples were divided into four separate batches and packed in plastic bags and sealed by an impulse sealer. Samples in plastic bags were exposed to different doses of gamma irradiation (2.5, 5 and 7 kGy) at ambient temperature. Just after irradiation, the samples were stored at 4 ±1 0 C. All samples were evaluated for microbiological, chemical and sensorial properties after irradiation and throughout the storage periods. During storage, the total bacterial count was significantly increased (P<0.05) in all samples with higher rates of increase in non-irradiated samples. In all irradiated samples, Staphylococcus aureus did not detected up to 6 days then detected after 22 days in samples treated with 2.5 kGy as well as 31 days in samples treated with 5 kGy. On the other hand, Staphylococcus aureus was detected after 45 days in samples treated with 7 kGy. Salmonella sp., Listeria monocytogenes and Campylobacter jejuni could not detected in untreated and treated samples. The protein content showed significant decrease immediately after irradiation and during the refrigerated storage. The TVN values for non-irradiated samples were significantly higher (P<0.05) than irradiated samples. The present data showed significant decrease (P<0.05) in protein solubility percentages of irradiated samples at day 0 and 6 of refrigerated storage. The observed decrease was related to the increase of radiation dose. At the end of storage period (62 days), 2.5 kGy samples were significantly higher in TBA values than other irradiated samples. On the other hand, irradiation was significantly reduced (P<0.05) the amount of major mono unsaturated and poly unsaturated fatty acids. Sensory attributes of breaded chicken breast fillets did not affected by irradiation. It could be concluded that irradiation dose of 5 kGy can be used in chicken samples stored in

Development of radiation safety monitoring system at gamma greenhouse gamma facility

International Nuclear Information System (INIS)

Hairul Nizam Idris; Azimawati Ahmad, Ahmad Zaki Hussain; Ahmad Fairuz Mohd Nasir

2009-01-01

This paper is discussing about installation of radiation safety monitoring system at Gamma Greenhouse Gamma facility, Agrotechnology and Bioscience Division (BAB). This facility actually is an outdoor type irradiation facility, which first in Nuclear Malaysia and the only one in Malaysia. Source Cs-137 (801 Curie) was use as radiation source and it located at the centre of 30 metres diameter size of open irradiation area. The radiation measurement and monitoring system to be equipped in this facility were required the proper equipment and devices, specially purpose for application at outside of building. Research review, literature study and discussion with the equipment manufacturers was being carried out, in effort to identify the best system should be developed. Factors such as tropical climate, environment surrounding and security were considered during selecting the proper system. Since this facility involving with panoramic radiation type, several critical and strategic locations have been fixed with radiation detectors, up to the distance at 200 meter from the radiation source. Apart from that, this developed system also was built for capable to provide the online real-time reading (using internet). In general, it can be summarized that the radiation safety monitoring system for outdoor type irradiation facility was found much different and complex compared to the system for indoor type facility. Keyword: radiation monitoring, radiation safety, Gamma Greenhouse, outdoor irradiation facility, panoramic radiation. (Author)

Positron annihilation studies on reactor irradiated and thermal annealed ferrocene

International Nuclear Information System (INIS)

Marques Netto, A.; Carvalho, R.S.; Magalhaes, W.F.; Sinisterra, R.D.

1996-01-01

Retention and thermal annealing following (n, γ) reaction in solid ferrocene, Fe(C 5 H 5 ) 2 , were studied by positron annihilation lifetime spectroscopy (PAL). Positronium (Ps) formation was observed in the non-irradiated compound with a probability or intensity (I 3 ) of 30%. Upon irradiation of the compound with thermal neutrons in a nuclear reactor, I 3 decreases with increasing irradiation time. Thermal treatment again increases I 3 values from 16% to 25%, revealing an important proportion of molecular reformation without variation of the ortho-positronium lifetime (τ 3 ). These results point out the major influence of the electronic structure as determining the Ps yields in the pure complex. In the irradiated and non irradiated complexes the results are satisfactorily explained on the basis of the spur model. (orig.)

Thermal Decompositon Studies Of Pre-Irradiated Nickel (II) Azides ...

African Journals Online (AJOL)

The effect of pre-irradiation on the thermal decomposition of three samples of nickel (II) azide was studied. It was found that the rates of thermal decomposition of Ni(OH)N3 increased substantially with increase in pre-irradiation dosage. The initial reaction rates change from time-dependant nucleation law for the unirradiated ...

Experimental and theoretical study of solid solution stability under irradiation

International Nuclear Information System (INIS)

Cauvin, Richard.

1981-08-01

The behavior of dilute alloys (Al-Zn, Al-Ag, Al-Si, Al-Ge and Al-Mg) under 1 MeV electron irradiation has been studied in a high voltage electron microscope. A phenomenon of homogeneous precipitation induced by irradiation in undersaturated solid solutions (Al-Zn, Al-Ag and Al-Si) has been discovered; the observed precipitates are either coherent or incoherent, but never associated with point defect sinks. The solubility limit is a function of irradiation temperature and flux; but, under irradiation, it does not behave as a true thermal solubility limit (without irradiation). The existing theories (kinetic or strictly thermodynamic) do not account for this phenomenon. It is shown that the irreversibility of the mutual recombination between trapped vacancies and mixed interstitials is the driving force of this homogeneous precipitation. Using a dilute solid solution model, we show that, under irradiation, the homogeneous stationary state, stable from a strictly thermodynamic point of view, can be unstable when the recombination reaction is taken into account. The solubility limit under irradiation is calculated with a nucleation-growth model taking account for this effect; it is proportional to the thermal solubility limit without irradiation. This model explains all the experimental observations [fr

Damage studies on tungsten due to helium ion irradiation

International Nuclear Information System (INIS)

Dutta, N.J.; Buzarbaruah, N.; Mohanty, S.R.

2014-01-01

Highlights: • Used plasma focus helium ion source to study radiation induced damage on tungsten. • Surface analyses confirm formation of micro-crack, bubbles, blisters, pinholes, etc. • XRD patterns confirm development of compressive stress due to thermal load. • Reduction in hardness value is observed in the case of exposed sample. - Abstract: Energetic and high fluence helium ions emitted in a plasma focus device have been used successfully to study the radiation induced damage on tungsten. The reference and irradiated samples were characterized by optical microscopy, field emission scanning electron microscopy, X-ray diffraction and by hardness testers. The micrographs of the irradiated samples at lower magnification show uniform mesh of cracks of micrometer width. However at higher magnification, various types of crystalline defects such as voids, pinholes, bubbles, blisters and microcracks are distinctly noticed. The prominent peaks in X-ray diffraction spectrum of irradiated samples are seen shifted toward higher Bragg angles, thus indicating accumulation of compressive stress due to the heat load delivered by helium ions. A marginal reduction in hardness of the irradiated sample is also noticed

EPR study on non- and gamma-irradiated herbal pills

Energy Technology Data Exchange (ETDEWEB)

Aleksieva, K., E-mail: katerina_bas@abv.b [Institute of Catalysis, Bulgarian Academy of Sciences, 1113 Sofia (Bulgaria); Lagunov, O. [Institute of Catalysis, Bulgarian Academy of Sciences, 1113 Sofia (Bulgaria); Dimov, K. [Institute of Cryobiology and Food Technologies, 1162 Sofia (Bulgaria); Yordanov, N.D. [Institute of Catalysis, Bulgarian Academy of Sciences, 1113 Sofia (Bulgaria)

2011-06-15

The results of EPR studies on herbal pills of marigold, hawthorn, yarrow, common balm, tutsan, nettle and thyme before and after gamma-irradiation are reported. Before irradiation all samples exhibit one weak singlet EPR line with a g-factor of 2.0048{+-}0.0005. After irradiation herbal pills could be separated in two groups according to their EPR spectra. Radiation-induced free radicals in pills of marigold, yarrow, nettle, tutsan and thyme could be attributed mainly to saccharide excipients. Tablets of hawthorn and common balm show 'cellulose-like' EPR spectrum, superimposed on partly resolved carbohydrate spectrum, due to the active part (herb) and inulin, which is present in the pills as an excipient. Fading study of the radiation-induced EPR signals confirms that sugar radicals are more stable than cellulose species. The reported results show that the presence of characteristic EPR spectra of herbal pills due to excipients or active part can be used as unambiguous proof of radiation processing within 35 or more days after irradiation.

Experimental study on active specific immunotherapy modified with irradiation

International Nuclear Information System (INIS)

Imanaka, Kazufumi; Ogawa, Yasuhiro; Gose, Kyuhei; Imajo, Yoshinari; Kumura, Shuji

1982-01-01

We have already reported that the effectiveness of active specific immunotherapy using irradiated tumor cells and infiltrating mononuclear cells which were separated from the topical tumor tissue 7 days after irradiation of 2,000 rad in experimental study. The present study was designed to investigate the effect of non-specific immunopotentiator PS-K combined with active specific immunotherapy. Female C3H/He mice aged 12 weeks were inoculated 4 x 10 6 MM 46 tumor cells in the right hind paws and received local electron irradiation with the dose of 3,000 rad on the 5th day after irradiation. Active specific immunotherapy was performed on the 12th day, and daily dose of 200 mg/kg of PS-K was injected intraperitoneally from the 6th day to the 10th day. The inhibition of the tumor growth and the elongation of survival period were noted in the group which received active specific immunotherapy combined with non-specific immunopotentiator, PS-K compared with the active specific immunotherapy alone. (author)

EPR study on non- and gamma-irradiated herbal pills

International Nuclear Information System (INIS)

Aleksieva, K.; Lagunov, O.; Dimov, K.; Yordanov, N.D.

2011-01-01

The results of EPR studies on herbal pills of marigold, hawthorn, yarrow, common balm, tutsan, nettle and thyme before and after gamma-irradiation are reported. Before irradiation all samples exhibit one weak singlet EPR line with a g-factor of 2.0048±0.0005. After irradiation herbal pills could be separated in two groups according to their EPR spectra. Radiation-induced free radicals in pills of marigold, yarrow, nettle, tutsan and thyme could be attributed mainly to saccharide excipients. Tablets of hawthorn and common balm show 'cellulose-like' EPR spectrum, superimposed on partly resolved carbohydrate spectrum, due to the active part (herb) and inulin, which is present in the pills as an excipient. Fading study of the radiation-induced EPR signals confirms that sugar radicals are more stable than cellulose species. The reported results show that the presence of characteristic EPR spectra of herbal pills due to excipients or active part can be used as unambiguous proof of radiation processing within 35 or more days after irradiation.

EPR study on non- and gamma-irradiated herbal pills

Science.gov (United States)

Aleksieva, K.; Lagunov, O.; Dimov, K.; Yordanov, N. D.

2011-06-01

The results of EPR studies on herbal pills of marigold, hawthorn, yarrow, common balm, tutsan, nettle and thyme before and after gamma-irradiation are reported. Before irradiation all samples exhibit one weak singlet EPR line with a g-factor of 2.0048±0.0005. After irradiation herbal pills could be separated in two groups according to their EPR spectra. Radiation-induced free radicals in pills of marigold, yarrow, nettle, tutsan and thyme could be attributed mainly to saccharide excipients. Tablets of hawthorn and common balm show "cellulose-like" EPR spectrum, superimposed on partly resolved carbohydrate spectrum, due to the active part (herb) and inulin, which is present in the pills as an excipient. Fading study of the radiation-induced EPR signals confirms that sugar radicals are more stable than cellulose species. The reported results show that the presence of characteristic EPR spectra of herbal pills due to excipients or active part can be used as unambiguous proof of radiation processing within 35 or more days after irradiation.

Serum protein concentration in low-dose total body irradiation of normal and malnourished rats

International Nuclear Information System (INIS)

Viana, W.C.M.; Lambertz, D.; Borges, E.S.; Neto, A.M.O.; Lambertz, K.M.F.T.; Amaral, A.

2016-01-01

Among the radiotherapeutics' modalities, total body irradiation (TBI) is used as treatment for certain hematological, oncological and immunological diseases. The aim of this study was to evaluate the long-term effects of low-dose TBI on plasma concentration of total protein and albumin using prematurely and undernourished rats as animal model. For this, four groups with 9 animals each were formed: Normal nourished (N); Malnourished (M); Irradiated Normal nourished (IN); Irradiated Malnourished (IM). At the age of 28 days, rats of the IN and IM groups underwent total body gamma irradiation with a source of cobalt-60. Total protein and Albumin in the blood serum was quantified by colorimetry. This research indicates that procedures involving low-dose total body irradiation in children have repercussions in the reduction in body-mass as well as in the plasma levels of total protein and albumin. Our findings reinforce the periodic monitoring of total serum protein and albumin levels as an important tool in long-term follow-up of pediatric patients in treatments associated to total body irradiation. - Highlights: • Low-dose total body irradiation (TBI) in children have repercussions in their body-mass. • Long-term total protein and albumin levels are affected by TBI. • The monitoring of total protein and albumin levels are useful in the follow-up of TBI pediatric patients.

Studies in mice fed a diet containing irradiated fish

International Nuclear Information System (INIS)

1979-01-01

Three groups of mice were observed in utero and for eighty (80) weeks thereafter to study growth, food consumption, hematology, blood chemistry and survival with particular interest in carcinogenic potential. Group I received only Purina Mouse Chow, Group II received a diet composed of 45% non-irradiated fish and 55% Purina Mouse Chow, and Group III received a diet composed of 45% gamma irradiated fish and 55% Purina Mouse Chow. Differences observed in body weights between control and fish treated diets were due to the incorporation of fish into the diet and not the results of fish being treated with gamma irradiation. Differences observed in food consumption between control and fish treated diets were due to the incorporation of fish into the diet and not the result of fish being treated with gamma irradiation. No daily observations were made which could be attributed to the treatment of fish with gamma irradiation. No observations were made at any time interval for hematology which could be attributed to the treatment of fish with gamma irradiation. No observations were made at any time interval for clinical chemistry which could be attributed to the treatment of fish with gamma irradiation. Palpable mass data did not reveal any trends which could be related to the treatment of fish with gamma irradiation. Gross observations at necropsy were limited to spontaneously occurring lesions or artifacts of necropsy technique commonly associated with animals of this species and age. Organ weight data did not reveal any trends which could be related to the treatment of fish with gamma irradiation. Pathological findings were limited to spontaneously occurring lesions or artifacts of necropsy technique commonly associated with animals of this species and age. (orig.)

Some conclusions of studies on irradiation of whole fish aboard fishing vessels

International Nuclear Information System (INIS)

Reinacher, E.; Ehlermann, D.A.E.

1978-01-01

Studies were conducted on irradiation of whole redfish and haddock (at 100 krad) and subsequent storage of the irradiated fish for up to approx. 30 days in ice. The fish were organoleptically evaluated at intervals during storage. The results show no significant difference in organoleptic quality between irradiated and non-irradiated samples during storage for [de

Study on neutron irradiation behavior of beryllium as neutron multiplier

Energy Technology Data Exchange (ETDEWEB)

Ishitsuka, Etsuo [Japan Atomic Energy Research Inst., Oarai, Ibaraki (Japan). Oarai Research Establishment

1998-03-01

More than 300 tons beryllium is expected to be used as a neutron multiplier in ITER, and study on the neutron irradiation behavior of beryllium as the neutron multiplier with Japan Materials Testing Reactor (JMTR) were performed to get the engineering data for fusion blanket design. This study started as the study on the tritium behavior in beryllium neutron reflector in order to make clear the generation mechanism on tritium of JMTR primary coolant since 1985. These experiences were handed over to beryllium studies for fusion study, and overall studies such as production technology of beryllium pebbles, irradiation behavior evaluation and reprocessing technology have been started since 1990. In this presentation, study on the neutron irradiation behavior of beryllium as the neutron multiplier with JMTR was reviewed from the point of tritium release, thermal properties, mechanical properties and reprocessing technology. (author)

Application of radiophotoluminescence dosemeters for environmental monitoring

International Nuclear Information System (INIS)

Mihara, A.; Tamura, T.; Mochizuki, T.; Numakunai, T.; Yoshida, Y.; Ohi, Y.

1993-01-01

Feasibility study has been made on the radiofluorescence glass (RPL) dosemeters for environmental radiation monitoring. Main items in the laboratory tests are batch uniformities of pre-dose and sensitivity, build-up characteristics of RPL intensity, energy and angular responses, stabilities for RPL reading, anneal cycling and climatic conditional changes. We have determined self-irradiation dose and cosmic ray contribution. Radiation monitoring field test for the RPL dosemeters has been conducted in comparison with the present TLD systems. A procedure manual for the environmental monitoring by the use of RPL dosemeters is in preparation

Comparison of neutron and gamma irradiation effects on KU1 fused silica monitored by electron paramagnetic resonance

Energy Technology Data Exchange (ETDEWEB)

Bravo, D. [Department Fisica de Materiales, Universidad Autonoma de Madrid, E-28049 Madrid (Spain)], E-mail: david.bravo@uam.es; Lagomacini, J.C. [Department Fisica de Materiales, Universidad Autonoma de Madrid, E-28049 Madrid (Spain); Leon, M.; Martin, P. [Materiales para Fusion, CIEMAT, Avda. Complutense 22, E-28040 Madrid (Spain); Martin, A. [Department Fisica e Instalaciones, ETS Arquitectura UPM, E-28040 Madrid (Spain); Lopez, F.J. [Department Fisica de Materiales, Universidad Autonoma de Madrid, E-28049 Madrid (Spain); Ibarra, A. [Materiales para Fusion, CIEMAT, Avda. Complutense 22, E-28040 Madrid (Spain)

2009-06-15

Electron paramagnetic resonance (EPR) studies have been carried out on KU1 fused silica irradiated with neutrons at fluences 10{sup 21} and 10{sup 22} n/m{sup 2}, and gamma-ray doses up to 12 MGy. The effects of post-irradiation thermal annealing treatments, up to 850 deg. C, have also been investigated. Paramagnetic oxygen-related defects (POR and NBOHC) and E'-type defects have been identified and their concentration has been measured as a function of neutron fluence, gamma dose and post-irradiation annealing temperature. It is found that neutrons at the highest fluence generate a much higher concentration of defects (mainly E' and POR, both at concentrations about 5 x 10{sup 18} spins/cm{sup 3}) than gamma irradiations at the highest dose (mainly E' at a concentration about 4 x 10{sup 17} spins/cm{sup 3}). Moreover, for gamma-irradiated samples a lower treatment temperature (about 400 deg. C) is required to annihilate most of the observed defects than for neutron-irradiated ones (about 600 deg. C)

The preliminary study on peculiar flavor from irradiated dried duck

International Nuclear Information System (INIS)

Li Zongju; Chen Zongdao; Xu Denyi

1992-01-01

Peculiar flavor may be induced from irradiative preservation of meat with higher dose. The study on the irradiation of dried duck indicated that peculiar flavor is produced by a threshold of 1.5 kGy and intensifies with the increase of dose. The flavor primarily comes from muscle of dried duck especially from its water soluble protein. With the increase of dose, volatile carbonyl compounds, amines and sulfur compounds increased significantly. Paper chromatography analysis shows that two new volatile carbonyl compounds (R f =0.23 and 0.28) and a new volatile amine-propamine are induced by irradiation. This compounds may be the source of peculiar flavor in irradiated dried duck

Report of the safety and wholesomeness of irradiated foods by the advisory committee on irradiated and novel foods

International Nuclear Information System (INIS)

1986-01-01

Following the conclusions of the Joint Expert Committee on the wholesomeness of Irradiated Foods(JECFI) an Advisory Committee on Irradiated and Novel Foods (ACINF) was set up to review the position relating to the irradiation of food and to report and advise on its findings to the Ministries of Health and Agriculture, with a view to changing legislation in the U.K. The advisory committee concluded that there were no justifications, on public health grounds, for the present U.K. regulations not to be amended and that the irradiation of foods up to an overall average dose of 10 Gy by X-rays and γ-rays up to 5 MeV, or for electrons up to 10 MeV, should be permitted. The committee recommended that food irradiation procedures and consumption patterns should be monitored. (UK)

Studies on irradiated BNFL culture medium for decontamination and longer storage

International Nuclear Information System (INIS)

Singh, Antaryami; Malodia, P.; Jain, S.K.; Ram Gopal

2001-01-01

The feasibility of gamma radiation for microbial decontamination and shelf-life extension of culture medium was studied. Changes in total viable count, coliform count and fungal count on exposure to 5, 10, 15, 20 and 25 kGy of gamma radiation were examined. The total viable counts were reduced on irradiation. Complete destruction of bacterial and fungal contamination was observed at 20 kGy. Studies were conducted to examine the changes in microbial contamination of the medium during storage. There was no post irradiation proliferation of microorganisms. Also, no significant change in the efficiency of the irradiated culture medium was observed. Thus, irradiation is extremely useful for longer storage and quality-assurance. (author)

Irradiation-related amorphization and crystallization: In situ transmission electron microscope studies

International Nuclear Information System (INIS)

Allen, C.W.

1994-01-01

Interfacing an ion accelerator to a transmission electron microscope (TEM) allows the analytical functions of TEM imaging and diffraction to be employed during ion-irradiation effects studies. At present there are twelve such installations in Japan, one in France and one in the US. This paper treats several aspects of in situ studies involving electron and ion beam induced and enhanced phase transformations and presents results of several in situ experiments to illustrate the dynamics of this approach in the materials science of irradiation effects. The paper describes the ion- and electron-induced amorphization of CuTi; the ion-irradiation-enhanced transformation of TiCr 2 ; and the ion- and electron-irradiation-enhanced crystallization of CoSi 2

Preliminary study on detection of irradiated foodstuffs from the Romanian market

International Nuclear Information System (INIS)

Cutrubinis, Mihalis; Chirita, Daniel; Savu, Diana; Elisabeta Secu, Corina; Mihai, Radu; Secu, Mihai; Ponta, Corneliu

2007-01-01

In order to fulfil the European task for market survey in food irradiation the first Romanian laboratory for detection of irradiated foodstuffs was established at IRASM Irradiation Centre. In this preliminary study, a wide range of Romanian food samples (spices, vegetables and meat) gamma irradiated at IRASM have been studied using different detection methods: (1) DNA comet assay, (2) thermoluminescence (TL) and (3) electron spin resonance (ESR) for foodstuffs containing bone or cellulose. The results suggest that there is no general available detection method and there is no perfect detection method. In conclusion, in order to carry out a correct identification of radiation treatment of a food sample it is recommended to use at least two standardised detection methods

Positron lifetime study of copper irradiated by energetic protons or energetic neutrons

International Nuclear Information System (INIS)

Howell, R.H.

1979-03-01

Positron lifetime measurements of pure copper damaged by irradiation with energetic protons and neutrons are presented. Lifetime determinations of the bulk material and various traps were made, and the dependence of the trapping rate on dose and irradiation energy were investigated. The results from the neutron- and proton-irradiated samples point to the existence of traps with similar but distinct lifetime parameters, not varying greatly from values reported in deformation studies. Also, a trap with long lifetime is seen for some proton irradiations, but is never seen for the neutron irradiations. The trapping rate of the short-lifetime trap is a linear function of dose for proton-irradiated samples and nearly so for the neutron irradiation. 1 figure

Ozone generation by nuclear irradiation of oxygen and oxygen-sulfur hexafluoride mixtures

International Nuclear Information System (INIS)

Elsayed-Ali, H.E.; Miley, G.H.

1984-01-01

A series of experimental measurements of 0/sub 3/ yield in nuclear induced 0/sub 2/ and 0/sub 2/-SF/sub 6/ discharges has been accomplished. The discharges were formed by irradiation with high-energy (MeV) He and Li ions created by neutron-induced nuclear reactions in Boron-10. Two experimental apparatus were utilized for this study; a flowing gas and a static in-core apparatus. In the former, 0/sub 2/ and 0/sub 2/-SF/sub 6/ mixtures were allowed to flow inside the irradiation cell for a known period of time. The irradiated mixture was then transported outside the reactor shielding where ozone concentrations were determined by measuring its absorption at 253.7nm. This set-up was used to study continuous irradiation with irradiation times varying from 0.1 to 0.7 seconds at dose rates of 10/sup 18/ - 10/sup 20/ eV g/sup -1/s/sup -1/. An in-core static system was utilized to monitor ozone buildup for continuous irradiation and to study yields when the reactor was pulsed giving a peak dose rate of 10/sup 24/ eV g/sup -1/s/sup -1/

Monitoring of gluconeogenesis in rats following chronic irradiation

Energy Technology Data Exchange (ETDEWEB)

Paulikova, E.; Sedlakova, A.; Praslicka, M. (Univerzita P.J. Safarika, Kosice (Czechoslovakia). Katedra Vseobecnej Biologie)

1984-01-01

A dose dependent cumulation of liver glycogen with the maximum on the day 120 was observed as was an increased incorporation of /sup 14/C-alanine in liver glycogen (statistically nonsignificant changes). The contribution of /sup 14/C-acetate to gluconeogenesis was negligible. The results showed increased gluconeogenesis in rats following chronic gamma irradiation with small daily dose rates (0.0957 Gy).

Monitoring of gluconeogenesis in rats following chronic irradiation

International Nuclear Information System (INIS)

Paulikova, E.; Sedlakova, A.; Praslicka, M.

1984-01-01

A dose dependent cumulation of liver glycogen with the maximum on the day 120 was observed as was an increased incorporation of 14 C-alanine in liver glycogen (statistically nonsignificant changes). The contribution of 14 C-acetate to gluconeogenesis was negligible. The results showed increased gluconeogenesis in rats following chronic gamma irradiation with small daily dose rates (0.0957 Gy)

Neutron irradiation effects in pressure vessel steels and weldments

Energy Technology Data Exchange (ETDEWEB)

Ianko, L [International Atomic Energy Agency, Vienna (Austria). Div. of Nuclear Power; Davies, L M

1994-12-31

This paper deals with the effects of neutron irradiation on the steel and welds used for the pressure vessels which house the reactor cores in light water reactors: irradiation effects on mechanical properties and the shift in ductile-brittle transition temperature, importance of the knowledge of the neutron fluence and of the monitoring and surveillance programmes; empirical and mechanistic modelling of irradiation effects and the necessity of data extension to new operational limits; consequences on the manufacturing and structural design of materials and structures; mitigation of irradiation effects by annealing; international activities and programmes in the field of neutron irradiation effects on PV steels and welds. 37 refs., 22 figs.

Vacancy defects in electron irradiated RPV steels studied by positron lifetime

Energy Technology Data Exchange (ETDEWEB)

Moser, P; Li, X H [CEA Centre d` Etudes de Grenoble, 38 (France). Dept. de Recherche Fondamentale sur la Matiere Condensee; Akamatsu, M; Van Duysen, J C [Electricite de France (EDF), 77 - Ecuelles (France)

1994-12-31

Specimens of French RPV (reactor pressure vessels) steels at different rates of segregation have been irradiated at 150 and 288 deg C with 3 MeV electrons (irradiation dose: 4*10{sup 19} e-/cm{sup 2}). Vacancy defects are studied by positron lifetime measurements before and after irradiation and at each step of isochronal annealing. After 150 deg C irradiation, a recovery step is observed in both specimens, for annealing treatments in the range 220-370 deg C and is attributed to the dissociation of vacancy-impurity complexes. The size of vacancy clusters never overcome 10 empty atomic volumes. If ``fresh`` dislocations are created just before irradiation, big vacancy clusters could be formed. After 288 deg C irradiation, small vacancy cluster of 4-10 empty atomic volumes are observed. (authors). 3 figs., 7 refs.

Development of a novel preclinical pancreatic cancer research model: bioluminescence image-guided focal irradiation and tumor monitoring of orthotopic xenografts.

Science.gov (United States)

Tuli, Richard; Surmak, Andrew; Reyes, Juvenal; Hacker-Prietz, Amy; Armour, Michael; Leubner, Ashley; Blackford, Amanda; Tryggestad, Erik; Jaffee, Elizabeth M; Wong, John; Deweese, Theodore L; Herman, Joseph M

2012-04-01

We report on a novel preclinical pancreatic cancer research model that uses bioluminescence imaging (BLI)-guided irradiation of orthotopic xenograft tumors, sparing of surrounding normal tissues, and quantitative, noninvasive longitudinal assessment of treatment response. Luciferase-expressing MiaPaCa-2 pancreatic carcinoma cells were orthotopically injected in nude mice. BLI was compared to pathologic tumor volume, and photon emission was assessed over time. BLI was correlated to positron emission tomography (PET)/computed tomography (CT) to estimate tumor dimensions. BLI and cone-beam CT (CBCT) were used to compare tumor centroid location and estimate setup error. BLI and CBCT fusion was performed to guide irradiation of tumors using the small animal radiation research platform (SARRP). DNA damage was assessed by γ-H2Ax staining. BLI was used to longitudinally monitor treatment response. Bioluminescence predicted tumor volume (R = 0.8984) and increased linearly as a function of time up to a 10-fold increase in tumor burden. BLI correlated with PET/CT and necropsy specimen in size (P < .05). Two-dimensional BLI centroid accuracy was 3.5 mm relative to CBCT. BLI-guided irradiated pancreatic tumors stained positively for γ-H2Ax, whereas surrounding normal tissues were spared. Longitudinal assessment of irradiated tumors with BLI revealed significant tumor growth delay of 20 days relative to controls. We have successfully applied the SARRP to a bioluminescent, orthotopic preclinical pancreas cancer model to noninvasively: 1) allow the identification of tumor burden before therapy, 2) facilitate image-guided focal radiation therapy, and 3) allow normalization of tumor burden and longitudinal assessment of treatment response.

Studies on mating competition of irradiated melon flies

International Nuclear Information System (INIS)

Limohpasmanee, W.

1994-01-01

Mating competition is the key factor for fruit flies control by using sterile insect technique project. Mass rearing and irradiation can reduce the mating competition of fruit flies. This experiment has purpose to evaluate the mating competition of the irradiated melon fly. The results show that mating competition values of irradiated melon flies were 0.36 and 0.24 when they mated with normal and irradiated females. Both normal male and female can mate more frequency than irradiated flies. (Z=1.322, P<0.05; Z=1.851, P<0.05). The results show that quality of mass rearing and irradiated melon fly was lower than the normal flies. So that quality of irradiated fly must be improved and the number of released flies as less must be higher than natural flies 6 time

Effect of gamma irradiation on nylon 6 films : swelling study

International Nuclear Information System (INIS)

Singh, L.P.; Chaudhuri, N.K.

1980-01-01

This paper reports on swelling studies of γ-irradiated nylon 6 films undertaken to investigate the effects of γ-irradiation in finer details. Benzyl alcohol has been used as the swelling agent. The kinetics of weight swelling of γ-irradiated nylon 6 films in benzyl alcohol was studied at different irradiation doses in the range 0 - 28.8 Mrad. It is observed that with increasing irradiation dose upto 14.4 Mrad the swelling, and hence the diffusion process are retarded; moreover, the sigmoidal nature of the percentage weight swelling vs (time)sup(1/2) plot is augmented. Above this critical dose the swelling and diffusion processes are accelerated. Besides, the sigmoidal behaviour recedes and is converted into linear behaviour at 28.8 Mrad. This behaviour indicates that a relaxation-controlled non-Fickian diffusion process is at work below 28.8 Mrad while at 28.8 Mrad a Fickian process is established. A significant effect on the equilibrium swelling in benzyl alcohol is observed. The plot of equilibrium weight swelling vs irradiation dose at 23deg C shows an initial decrease of swelling upto 3.6 Mrad at which swelling starts decreasing at accelerated rate in the dose range 3.6 - 7.6 Mrad. The rate slows down appreciably between 7.00 and 14.4 Mrad, above which there is a rapid fall. The results are correlated with scission and crosslinking processes through relative viscosity determination of formic acid solutions of the irradiated samples. It is established by combining viscosity data with kinetics and equilibrium swelling data that, besides scission, crosslinking processes are also at work in nylon 6 in the irradiation dose range 0 - 3.6 Mrad. It has been possible to bring out this point because the swelling technique seems to be preferentially sensitive towards crosslinking. (author)

Procedures for operational monitoring of the environmental equivalent doses in cobalt therapy

International Nuclear Information System (INIS)

Perez Velasquez, Reytel; Gonzalez Lopez, Nadia; Perez Tamayo, Luis

2009-01-01

It took as its object of study environmental equivalent dose rates of field radiation they face radiophysicists technicians and medical physicists in the irradiation site of the radiation department of Lenin Hospital in Holguin, and the public that travels or remains in premises and areas surrounding the campus. It A review of national and international publications as well as technical documents to study the state of the art of the methodological existing monitoring of those dose rates and the valuation of impact in the context of an environmental management system. Since no detailed instructions and to perform the above-mentioned monitoring was proposed structure should contain a procedure to regulate the steps for this monitoring in the radiotherapy department of the Lenin Hospital Holguin, for which we studied the guidelines of NC ISO 14000 , and was conducted wide experiment whose led to: illustrate the level of doses required workers exposed occupationally exposed to radiation and the public compare these levels with natural radiation sources, assess the effectiveness of shielding the site of irradiation and the points of greatest risk within and outside the enclosure irradiation.Also assessed the impact it can have on the health of people exposed to such doses. Finally, we proposed a procedure for conducting subsequent monitoring and made recommendations to reduce levels radiation determined the lowest level reasonably achievable. (author)

Experimental studies on prevention of trichinosis by food irradiation (Co60)

International Nuclear Information System (INIS)

Shimazu, Kimitaka

1993-01-01

A systemic study was performed to elucidate the effects of 60 Co irradiation on maturation or fecundity of Trichinella spiralis by assessing from parasitological, morphological and immunological points of view. Pieces of muscle tissue of mice infected with T. spiralis were irradiated with 60 Co at doses of 50, 75, 100, 150 and 200 Gy. These irradiated tissue (Experimental group) and non-irradiated tissues (Control group) were fed to healthy mice. Half of the mice were sacrificed 6 days after the ingestion. The number of adult worms were counted and subjected to statistical analysis, which disclosed a good correlation between the dose of 60 Co irradiation and worm damage; the higher the dose the more damage parasites had, and no adults were recovered if the tissue had been irradiated with more than 150 Gy prior to infection. The same tendency was true for the histopathology of the intenstines of host mice; the higher the dose the less tissue damage. Circulating antigens of T. spiralis and antibodies against T. spiralis were detected in every serum examined by ELISA. The remaining mice were sacrificed 30 days after the ingestion. The numbers of muscle larvae were counted and subjected to statistical analysis, which disclosed a good correlation between th dose of 60 Co irradiation and worm damage, and no larvae were recovered if the tissue had been irradiated with more than 75Gy. Higher concentrations of circulating antigens of T. spiralis and antibodies against T. spiralis were detected in the serum samples taken with muscle larvae. Thus this study established that 60 Co irradiation of more than 150 Gy caused complete damage on maturation, and that irradiation of more than 75 Gy caused complete damage on the fecundity of T. spimalis. (author)

Preliminary Studies for the Application of Irradiated-Food to Food Service Industry

Energy Technology Data Exchange (ETDEWEB)

Lee, Ju-Woon; Byun, Myung-Woo; Kim, Jae-Hun; Choi, Jong-Il; Song, Beom-Seok; Kim, Dong-Ho; Seo, Min-Won

2008-04-15

This study is to investigate ways to improve the marketability of irradiated food materials, through examining reports on toxicological safety and public acceptance of irradiated food materials. Many studies have reaffirmed the mutagenic, genotoxicological, microbiological, and nutritional safety of food irradiation, and consider it an important tool to reduce loss of food due to spoilage and pests. Although food irradiation could provide an opportunity to replace certain pesticides and food additives, there is ambivalence among consumers on whether or not the technology provides a real benefit. An easy and inexpensive tool to identify irradiation trace residue in foods, public trust building in industry through educating consumers with the benefit and uses of irradiation process are thought to be key elements for a successful market for irradiated food. Gamma irradiation at 50 kGy was applied to food materials for institutional food-service to evaluate their possible genotoxicity. The genotoxicity of 12 kinds of food materials irradiated at 50 kGy for institutional food-service was evaluated by Salmonella typhimurium reversion assay, chromosomal aberration test and in vivo micronucleus assay. The results of bacterial reversion assay with S. typhimurium TA98, TA100, TA1535 and TA1537 were negative in the 12 kinds of food materials irradiated at 50 kGy. No mutagenicity was detected in the assay with and without metabolic activation. In chromosomal aberration tests with CHL cells and in vivo mouse micronucleus assay, no significant difference in the incidences of chromosomal aberration and micronuclei was observed between non-irradiated and 50 kGy-irradiated food materials. These results indicate that food materials irradiated at 50 kGy for institutional food-service did not show any genotoxic effects under these experimental conditions.

Preliminary Studies for the Application of Irradiated-Food to Food Service Industry

International Nuclear Information System (INIS)

Lee, Ju-Woon; Byun, Myung-Woo; Kim, Jae-Hun; Choi, Jong-Il; Song, Beom-Seok; Kim, Dong-Ho; Seo, Min-Won

2008-04-01

This study is to investigate ways to improve the marketability of irradiated food materials, through examining reports on toxicological safety and public acceptance of irradiated food materials. Many studies have reaffirmed the mutagenic, genotoxicological, microbiological, and nutritional safety of food irradiation, and consider it an important tool to reduce loss of food due to spoilage and pests. Although food irradiation could provide an opportunity to replace certain pesticides and food additives, there is ambivalence among consumers on whether or not the technology provides a real benefit. An easy and inexpensive tool to identify irradiation trace residue in foods, public trust building in industry through educating consumers with the benefit and uses of irradiation process are thought to be key elements for a successful market for irradiated food. Gamma irradiation at 50 kGy was applied to food materials for institutional food-service to evaluate their possible genotoxicity. The genotoxicity of 12 kinds of food materials irradiated at 50 kGy for institutional food-service was evaluated by Salmonella typhimurium reversion assay, chromosomal aberration test and in vivo micronucleus assay. The results of bacterial reversion assay with S. typhimurium TA98, TA100, TA1535 and TA1537 were negative in the 12 kinds of food materials irradiated at 50 kGy. No mutagenicity was detected in the assay with and without metabolic activation. In chromosomal aberration tests with CHL cells and in vivo mouse micronucleus assay, no significant difference in the incidences of chromosomal aberration and micronuclei was observed between non-irradiated and 50 kGy-irradiated food materials. These results indicate that food materials irradiated at 50 kGy for institutional food-service did not show any genotoxic effects under these experimental conditions

The preliminary study on peculiar flavor from irradiated dried duck

Energy Technology Data Exchange (ETDEWEB)

Zongju, Li; Zongdao, Chen; Denyi, Xu [Southwest Agricultural Univ., Chongqing, SC (China)

1992-11-01

Peculiar flavor may be induced from irradiative preservation of meat with higher dose. The study on the irradiation of dried duck indicated that peculiar flavor is produced by a threshold of 1.5 kGy and intensifies with the increase of dose. The flavor primarily comes from muscle of dried duck especially from its water soluble protein. With the increase of dose, volatile carbonyl compounds, amines and sulfur compounds increased significantly. Paper chromatography analysis shows that two new volatile carbonyl compounds (R[sub f] =0.23 and 0.28) and a new volatile amine-propamine are induced by irradiation. This compounds may be the source of peculiar flavor in irradiated dried duck.

Wholesomeness study of irradiated salted and dried mackerel in rats

International Nuclear Information System (INIS)

Anukarahanonta, T.; Temcharoen, P.; Nagara, B.N.; Chudhabuddhi, C.; Bhamarapravati, N.

1981-01-01

A long-term multigeneration study was performed of the wholesomeness of irradiated salted and dried mackerel fed to the rats of Wistar strain and revealed no significant evidence that would impose a hazard attributable to irradiation with respect to the longevity, carcinogenecity, teratogenicity, dominant lethal, reproductive function and biophysiological function. Some abnormalities that were noted could be explained on the basis of differences in food quality due to the addition of fish protein and minerals rather than the irradiation effect

Preliminary study of killing the larva of plodia interpunella by irradiation

International Nuclear Information System (INIS)

Wang Jide; Ma Xiaoping

1994-01-01

The results of killing the larva of plodia interpunella in the fruit by 60 Co γ-irradiation are described. The lowest effective dose for killing larva by irradiation is ca. 2000 Gy; the effective dose for immediately killing larva is 3000 Gy. The method is simple and easy and also suitable for the study of commercial irradiation of dry-fruit

Studies on the irradiated solids

International Nuclear Information System (INIS)

Lesueur, D.

1988-01-01

The 1988 progress report of the Irradiated Solids laboratory (Polytechnic School, France), is presented. The Laboratory activities concern the investigations on disordered solids (chemical or structural disorder). The disorder itself, its effects on the material physical properties and the particle-matter interactions, are investigated. The research works are performed in the following fields: solid state physics, irradiation and stoechiometric defects, and nuclear materials. The scientific reviews, the congress communications and the thesis are listed [fr

Thermal studies on unirradiated and γ-irradiated polymer of allyl diglycol carbonate

International Nuclear Information System (INIS)

Kalsi, P.C.; Pandey, A.K.; Iyer, R.H.; Singh Mudher, K.D.

1995-01-01

The thermal decomposition of unirradiated and γ-irradiated (5.93-15.5 MRad dose range) allyl diglycol carbonate polymer (trade name, CR-39) was studied by thermogravimetry (TG) and differential thermal analysis (DTA). These studies indicate four main decomposition steps in CR-39 polymer in air. Assessment of the influence of radiation dose on the above range shows that while the 5.93 MRad γ-irradiated polymer CR-39 degrades in three steps, the 15.5 MRad γ-irradiated polymer degrades in only two steps. The kinetics of the different stages of degradation were also evaluated from the TG curves. Irradiation enhances the decomposition rate and the effect increases further with increasing radiation dose. The activation energy values calculated for all the decomposition stages decrease on irradiation

Study on the physiological activities of gamma-irradiated seafood cooking drips

International Nuclear Information System (INIS)

Jo, Eu Ri; Kim, Yeon Joo; Choi, Jong Il; Sung, Nak Yun; Jung, Pil Moon; Kim, Jae Hun; Song, Beom Seok; Yoon, Yo Han; Lee, Ju Woon; Lee, Ju Yeoun

2010-01-01

Cooking drips which were obtained as by-product after seafood processing in the food industries, still contain lost of proteins, carbohydrates, and other functional materials. This study was conducted to investigate the effect of gamma irradiation on the biological activities of seafood cooking drips. When the cooking drips of Hizikia fusiformis, Enteroctopus dofleini and Thunnus thynnus were irradiated, the antioxidant activities, whitening effect, and angiotensin I converting enzyme inhibition activity of the ethanol extract from seafood cooking drips were all increased by gamma irradiation. This was because of the increased extraction efficiency of available compounds by irradiation. These results suggested that the seafood cooking drips, wasted as by-products, can be used as functional compounds with gamma irradiation treatment

Study on the physiological activities of gamma-irradiated seafood cooking drips

Energy Technology Data Exchange (ETDEWEB)

Jo, Eu Ri; Kim, Yeon Joo; Choi, Jong Il; Sung, Nak Yun; Jung, Pil Moon; Kim, Jae Hun; Song, Beom Seok; Yoon, Yo Han; Lee, Ju Woon [Korea Atomic Energy Research Institute, Jeongeup (Korea, Republic of); Lee, Ju Yeoun [Chonbuk National University, Jeonju (Korea, Republic of)

2010-03-15

Cooking drips which were obtained as by-product after seafood processing in the food industries, still contain lost of proteins, carbohydrates, and other functional materials. This study was conducted to investigate the effect of gamma irradiation on the biological activities of seafood cooking drips. When the cooking drips of Hizikia fusiformis, Enteroctopus dofleini and Thunnus thynnus were irradiated, the antioxidant activities, whitening effect, and angiotensin I converting enzyme inhibition activity of the ethanol extract from seafood cooking drips were all increased by gamma irradiation. This was because of the increased extraction efficiency of available compounds by irradiation. These results suggested that the seafood cooking drips, wasted as by-products, can be used as functional compounds with gamma irradiation treatment.

Genetic efficiency of low-dose chronic irradiation in mammals and fish

International Nuclear Information System (INIS)

Goncharova, R.; Ryabokon, N.; Smolich, I.; Slukvin, A.

2001-01-01

The problem of biological effects of low-dose chronic irradiation is central radiobiological problem and seems to be very important for human monitoring and risk assessment Since 1986 we are engaged in studying genetic effects of low-dose chronic irradiation in natural populations of small mammals (bank vole - Clethrioiiomys glareolus) inhabiting radiocontaminated monitoring sites, in laboratory hybrid mice CBA*C57BI/6 j exposed to chronic irradiation at radiocontaminated sites, as well as in pond carp (Cyprinus carpio) reared in fish farms in areas contaminated due to the Chernobyl accident. The mean ground depositions in monitoring sites were 8-2330 kBq/m 2 and the mean bottom depositions in ponds were 52-3235 Bq/kg for Cs 137. We used conventional cytogenetics and genetics tests [1-3] and the following approaches in studying on genetic effects of low-dose chronic irradiation: Radiation exposures from external γ- and internal α, β, γ-irradiation from incorporated radionuclides were estimated for each specimen tested. Regression analysis of dose-effect relationships based on comparison of individual genetic end-points with individual absorbed doses was carried out We observed statistically significant changes in the frequencies of genetic end-points, which have been studied in somatic and germ cells, as well as in embryos of irradiated mammals and fish. So, the frequencies of chromosome aberrations in bank vole populations had up to 7-fold increase in comparison with background and pre-accident levels. It is of great importance to emphasize high radio-sensitivity of fertilized eggs (zygotes) and pond carp, embryos produced by chronically irradiated parents. Regression analysis allowed to reveal dependence of the studied parameters' frequencies on radiation exposure namely on the concentrations of basic dose forming radionuclides, absorbed dose rate and whole body absorbed dose. In most cases, dose-effect relationships were better approximated by non

Autonomous monitoring unit, signs and registration for Cobalt-60 irradiator safety system

Energy Technology Data Exchange (ETDEWEB)

Baldaconi, Ricardo H.; Costa, Fabio E. da, E-mail: ricardohovacker@hotmail.com, E-mail: fecosta@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

2015-07-01

The Cobalt-60 irradiator of IPEN / CNEN, a category IV facility, has a security system for inter locking doors or exposure of radioactive sources made simultaneously by a programmable logic controller (PLC) model S7- 200 from Siemens and a relay logic. From a set of information, the both systems work together opening doors or exposing the sources. All incoming and outgoing information are sent serially via EIA232 communication to a personal computer with Windows® platform for a supervisory program which provides besides a monitoring the entire process by a synoptic table on the computer screen, also keeps records of all events on the computer's hard drive. The electronic management has proven to be efficient and has not produced any failure that had compromised the safety. The PLC along with the relay logic has always taken the right decisions ensuring proper radiation protection of operators and the integrity of radioactive sources, but it presented over the years of operation (beginning in 2004) less than a dozen flaws in system event log. The deficiency was found between the process of sending events via serial communication (EIA232) to the supervisory program. When failure occurs in a very short time, the PLC always took the right decision, but the registration process that had to go through the Windows® timeshare lost the information. This work aimed to build a standalone electronics connect the inputs and outputs of the security system, fully optocoupled to avoid any interference to the security system. It records each event on a memory card, waits for the right decision of the security system and in case of an incorrect decision an independent alarm notifies its own synoptic picture, and sends a text message to a group of defined cell phones. The circuit uses two microcontrollers called 'main' and 'secondary'. The main is responsible for the control and monitoring of peripheral inputs and outputs of the security system. The main is

Autonomous monitoring unit, signs and registration for Cobalt-60 irradiator safety system

International Nuclear Information System (INIS)

Baldaconi, Ricardo H.; Costa, Fabio E. da

2015-01-01

The Cobalt-60 irradiator of IPEN / CNEN, a category IV facility, has a security system for inter locking doors or exposure of radioactive sources made simultaneously by a programmable logic controller (PLC) model S7- 200 from Siemens and a relay logic. From a set of information, the both systems work together opening doors or exposing the sources. All incoming and outgoing information are sent serially via EIA232 communication to a personal computer with Windows® platform for a supervisory program which provides besides a monitoring the entire process by a synoptic table on the computer screen, also keeps records of all events on the computer's hard drive. The electronic management has proven to be efficient and has not produced any failure that had compromised the safety. The PLC along with the relay logic has always taken the right decisions ensuring proper radiation protection of operators and the integrity of radioactive sources, but it presented over the years of operation (beginning in 2004) less than a dozen flaws in system event log. The deficiency was found between the process of sending events via serial communication (EIA232) to the supervisory program. When failure occurs in a very short time, the PLC always took the right decision, but the registration process that had to go through the Windows® timeshare lost the information. This work aimed to build a standalone electronics connect the inputs and outputs of the security system, fully optocoupled to avoid any interference to the security system. It records each event on a memory card, waits for the right decision of the security system and in case of an incorrect decision an independent alarm notifies its own synoptic picture, and sends a text message to a group of defined cell phones. The circuit uses two microcontrollers called 'main' and 'secondary'. The main is responsible for the control and monitoring of peripheral inputs and outputs of the security system. The main is

Improving quality of some types of cheese by gamma irradiation

International Nuclear Information System (INIS)

Sallam, E.M.E.A

2010-01-01

The use of ionizing radiation as a food preservation technique has been recognized for many years as a means to reduce food losses, improve food safety, and extend shelf life. Furthermore, irradiation can be an effective way of reducing the incidence of food borne disease and treating a variety of potential problems in food supplies. The treatment of food with ionizing radiation is one of the most thoroughly researched techniques available to the food processing industry. In view of the afore mentioned the objective of this study were to study the effect of irradiation time and dose on Ras cheese quality, investigate the effect of irradiation after ripening on cheese quality and possibility of prolonging the shelf-life of Ras cheese, study the effect of irradiation dose on Kareish cheese quality and its shelf- life and to monitor the chemical, microbiological and sensory changes during ripening and storage of Ras and Kareish cheeses .The results of this study will be presented in three parts: Part I: Effect of irradiation dose and time on some properties of Ras cheese:Part II: Effect of irradiation on some properties during storage of ripened Ras cheese.Part III: Effect of irradiation on the quality and shelf-life of Kareish cheese: It could be concluded that irradiation caused a significant reduction of cheese ripening indices, and count of total viable,proteolytic, lipolytic bacteria and mould and yeast. Using irradiation doses of 3 and 4 kGy were able to stop the ripening factors and these safety dose were used to prevent the ripened Ras cheese irradiation of ripened Ras cheese has been prolonged the shelf-life of Ras cheese to about 32 months compared with control cheese, which showed only 18 months. The obtained results revealed that the best irradiation treatment was at the end of ripening period. Also safety irradiation of Kareish cheese has been prolonged the shelf-life of Kareish cheese to about 54 days compared with 12 days only control cheese.

The Next Generation Nuclear Plant/Advanced Gas Reactor Fuel Irradiation Experiments in the Advanced Test Reactor

International Nuclear Information System (INIS)

Grover, S. Blaine

2009-01-01

The United States Department of Energy's Next Generation Nuclear Plant (NGNP) Program will be irradiating eight separate low enriched uranium (LEU) tri-isotopic (TRISO) particle fuel (in compact form) experiments in the Advanced Test Reactor (ATR) located at the Idaho National Laboratory (INL). The ATR has a long history of irradiation testing in support of reactor development and the INL has been designated as the new United States Department of Energy's lead laboratory for nuclear energy development. The ATR is one of the world's premiere test reactors for performing long term, high flux, and/or large volume irradiation test programs. These irradiations and fuel development are being accomplished to support development of the next generation reactors in the United States, and will be irradiated over the next ten years to demonstrate and qualify new particle fuel for use in high temperature gas reactors. The goals of the irradiation experiments are to provide irradiation performance data to support fuel process development, to qualify fuel for normal operating conditions, to support development and validation of fuel performance and fission product transport models and codes, and to provide irradiated fuel and materials for post irradiation examination (PIE) and safety testing. The experiments, which will each consist of at least six separate capsules, will be irradiated in an inert sweep gas atmosphere with individual on-line temperature monitoring and control of each capsule. The sweep gas will also have on-line fission product monitoring on its effluent to track performance of the fuel in each individual capsule during irradiation. The first experiment (designated AGR-1) started irradiation in December 2006, and the second experiment (AGR-2) is currently in the design phase. The design of test trains, as well as the support systems and fission product monitoring system that will monitor and control the experiment during irradiation will be discussed. In

Study of gamma irradiation effect on commercial TiO2 photocatalyst

International Nuclear Information System (INIS)

Bello Lamo, M.P.; Williams, P.; Reece, P.; Lumpkin, G.R.; Sheppard, L.R.

2014-01-01

The aim of this work is to understand the effect of gamma irradiation on commercial TiO 2 photocatalyst for water treatment applications. Previous studies concluded that gamma-irradiation is able to modify the electronic properties of TiO 2 based photocatalysts and consequently their photocatalytic performance. However, there are some discrepancies in the literature where on one hand a significant enhancement of the material properties is reported and on the other hand only a weak effect is observed. In this study a surface effect on TiO 2 is confirmed by using low and medium gamma irradiation doses. - Highlights: • Gamma irradiated TiO 2 is investigated for photocatalytic water treatment. • By low gamma doses, no change in surface properties is observed. • However, a surface defect is found for gamma irradiated TiO 2 at higher doses. • XPS measurements showed an increase of hydroxyl groups. • That may cause a variation of its adsorption capacity

Multigeneration feeding studies with an irradiated whole diet

International Nuclear Information System (INIS)

Aravindakshan, M.; Chaubey, R.C.; Chauhan, P.S.; Sundaram, K.

1978-01-01

Multigeneration feeding studies have been carried out to investigate the effects of long-term feeding of an irradiated whole diet in Wistar rats. The parent and the four successive generations were fed on a nutritionally adequate test diet exposed to either 0.2 or 2.5Mrad gamma radiation and the effects, if any, on various parameters of animal health were assessed. In addition to an unirradiated test control, a historical control group fed on stock laboratory rations was also employed for comparison. The test diet consisted of various components including some of the basic ingredients of human diet in India. Exposure of the test diet to 0.2 or 2.5Mrad did not affect the food efficiency ratio and there were no significant differences in the growth rates of animals fed on unirradiated or irradiated diets. Reproductive performance of the rats fed on irradiated or unirradiated diets belonging to the parent, first, second or third generations were also comparable. Mortality rates and reproductive function in relation to age were also not altered due to feeding of irradiated whole diets. The haematological profile and the serum enzymes of the animals of all the generations fed irradiated diets were within normal limits. Though some differences were observed in the relative weights of some organs, these effects were limited to a particular generation, did not show any definite pattern and could not be related to the ingestion of irradiated diets. First-generation rats examined at 100-104 weeks for gross pathological manifestations including tumour incidence also did not indicate any significant differences among groups. (author)

Defect studies in electron-irradiated ZnO and GaN

International Nuclear Information System (INIS)

Tuomisto, F.; Look, D.C.; Farlow, G.C.

2007-01-01

We present experimental results obtained with positron annihilation spectroscopy in room-temperature electron-irradiated n-type ZnO and GaN. The cation vacancies act as important compensating centers in 2 MeV electron-irradiated samples, even though their introduction rates are different by 2 orders of magnitude. In addition, negatively charged non-open volume defects that also compensate the n-type conductivity are produced together with the cation vacancies at similar introduction rates. The low introduction rates of compensating defects in ZnO demonstrate the radiation hardness of the material. Isochronal thermal annealings were performed to study the dynamics of the irradiation-induced defects. In 2 MeV electron-irradiated ZnO, all the defects introduced in the irradiation disappear already at 600 K, while 1100 K is needed in GaN. Several separate annealing stages of the defects are observed in both materials, the first at 400 K

Defect studies in electron-irradiated ZnO and GaN

Energy Technology Data Exchange (ETDEWEB)

Tuomisto, F. [Laboratory of Physics, Helsinki University of Technology, 02015 TKK Espoo (Finland)], E-mail: filip.tuomisto@tkk.fi; Look, D.C. [Semiconductor Research Center, Wright State University, Dayton, OH 45435 (United States); Materials and Manufacturing Directorate, Air Force Research Laboratory, Wright-Patterson Air Force Base, OH 45433 (United States); Farlow, G.C. [Physics Department, Wright State University, Dayton, OH 45435 (United States)

2007-12-15

We present experimental results obtained with positron annihilation spectroscopy in room-temperature electron-irradiated n-type ZnO and GaN. The cation vacancies act as important compensating centers in 2 MeV electron-irradiated samples, even though their introduction rates are different by 2 orders of magnitude. In addition, negatively charged non-open volume defects that also compensate the n-type conductivity are produced together with the cation vacancies at similar introduction rates. The low introduction rates of compensating defects in ZnO demonstrate the radiation hardness of the material. Isochronal thermal annealings were performed to study the dynamics of the irradiation-induced defects. In 2 MeV electron-irradiated ZnO, all the defects introduced in the irradiation disappear already at 600 K, while 1100 K is needed in GaN. Several separate annealing stages of the defects are observed in both materials, the first at 400 K.

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)

Positron annihilation and Moessbauer studies of neutron irradiated reactor pressure vessel steels

International Nuclear Information System (INIS)

Brauer, G.; Matz, W.; Liszkay, L.; Molnar, B.

1990-11-01

Positron annihilation (lifetime, Doppler broadening) and Moessbauer studies on unirradiated, neutron irradiated and neutron irradiated plus annealed reactor pressure vessel steels (Soviet type 15Kh2NMFA) are presented. The role of microstructural properties and the formation of irradiation-induced precipitates is discussed. (orig.) [de

Comparative study of thermoluminescence detection methods for irradiated spices

International Nuclear Information System (INIS)

Kawamura, Y.; Kojima, K.; Sugita, T.; Yamada, T.; Saito, Y.

1995-01-01

The thermoluminescence (TL) detection methods for irradiated spices were compared using spice samples obtained on the Japanese market, irradiated at doses of 1, 5, 10 and 30 kGy and stored for 1 year before analysis. The TL intensities of irradiated spices were stable for 1 year after irradiation. Measurement with whole samples failed to identify irradiated samples. Minerals were separated from spices in sodium tungstate saturated solution and/or sodium polytungstate solution. The TL intensity of minerals which had undergone irradiation was significantly increased for all samples. However, the ranges of TL intensity of irradiated and unirradiated samples overlapped. Clear discrimination has been obtained between the TL ratios of irradiated and unirradiated spices by using normalized measurement with reirradiation. The detection limit in terms of irradiation dose is 1 kGy even in a sample that has been irradiated 1 year prior to analysis. Normalization is the best technique currently available for thermoluminescence analysis to identify irradiated spices

Study on the irradiation decontamination of traditional Chinese medicines

International Nuclear Information System (INIS)

Wang, B.; Shi, S.; Li, B.; Wang, G.

2005-01-01

Traditional Chinese Medicines (TCMs) are natural products prepared from plants, minerals and animals, it is easy for contamination by microorganisms to occur; thus causing problems in complying with the requirements laid down for passing microbial limit tests. We selected some kinds of TCMs, including unprocessed materia medica, traditional Chinese patent medicine (TCPMs) and chemical constituents for irradiation by 60 Co gamma ray and investigating the results in terms of microbiology, chemistry, pharmacology and toxicology. We found no evidence of changes in most of the tested items, which indicates that the irradiation method could be employed for decontamination of TCMs. However, some chemical constituents of unprocessed materia medica, such as gentiopicrin in Radix Gentianae Macrophyllae and 2,3,5,4'-tetrahydroxystilbene-2-O-β-D-glucoside in Radix Polygoni Multiflori, decomposed when these crude materials were irradiated with dose of 5kGy. Further study revealed that although the medicinal were altered by irradiation, the monomers of some of these chemical constituents were not affected. In addition to investigation of the items described above, the doses of irradiation were selected experimentally to ensure that, after irradiation, the TCMs passed the microbial limit tests described in the Chinese Pharmacopoeia. The lowest possible doses were used in order to avoid any impairment of the quality and clinical efficacy of the effective ingredients of the TCMs. (author)

Fundamental irradiation studies on vanadium alloys

International Nuclear Information System (INIS)

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

1985-05-01

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

Studies on combination effects of peplomycin and x-ray irradiation

International Nuclear Information System (INIS)

Munenaga, Yasuichi

1984-01-01

In order to study effects and methods of combination of peplomycin (PEP) and x-ray irradiation, inhibitory effects on DNA synthesis were investigated with synchronized cells from the parotid gland of mice treated with isoproterenol (IPR) and inhibitory effects on cell proliferation were investigated with Ehrlich solid tumor cells. PEP had dose-dependent effects on the inhibition of DNA synthesis and on the prolongation of cell cycles in the IPR-treated mouse cells. When 3.0 and 5.0 mg/kg of PEP were combined with 200 rad of x-ray irradiation at the early phase of G 1 , synergistic effects on the inhibition of DNA synthesis were seen. This was most noted in the group with PEP 30 minutes before irradiation. PEP had also dose-dependent inhibitory effects on the proliferation of Ehrlich solid tumor cells. This was increased when x-ray irradiation was combined with PEP. Inhibitory effects on the proliferation of tumor cells were greater when PEP was given before x-ray irradiation than after x-ray irradiation, regardless of the amount. The greatest effect was seen in the group with PEP 30 minutes before irradiation, as well as in the experiment with IPR-treated mouse cells. (Namekawa, K.)

Caramel fuel for research reactors: experience acquired in the fabrication, monitoring and irradiation of Osiris core

International Nuclear Information System (INIS)

Contenson, Ghislain de; Foulquier, Henri; Trotabas, Maria; Vignesoult, Nicole; Cerles, J.-M.; Delafosse, Jacques.

1981-06-01

A plate type nuclear fuel (Caramel fuel) has been developed in France in the framework of the various activities pursued in the design, fabrication and development of nuclear fuels by the CEA. This fuel can be adapted to various different categories of water cooled reactor (power reactors, marine propulsion reactors, urbain heating reactors, research reactors). The successful work conducted in this field led the realization of a complete core and reloads for the high performance research reactor, Osiris, at Saclay. The existing highly enriched U-Al alloy fuel was replaced by a non-proliferating low enrichment (7%) caramel fuel. This new core has been operating successfully since january 1980. A brief description of Caramel and its main advantages is given. The way in which it is fabricated is described together with the quality controls to which it is subjected. The qualification program and the main results deduced from it are also presented. The program used to monitor its in-pile behavior is described. The essential purpose of this program is to ensure the high performance of the fuel under irradiation. The successful operation of Osiris, which terminated 11 irradiation cycles on the 21st of April 1981 confirmed the correctness of the decisions made and the excellent performance that could be achieved with these fuel elements under the severe conditions encountered in a high performance research reactor [fr

Irradiation Effects of Electron Beam on Optical Fibers

Energy Technology Data Exchange (ETDEWEB)

Kim, Jin Kyu; Cho, Gyu Seong [KAIST, Daejeon (Korea, Republic of); Choi, Hong Gu; Oh, Kyung Hwan [Yonsei University, Seoul (Korea, Republic of); Cho, Ho Jin [Nucron Co. Ltd., Seoul (Korea, Republic of)

2009-10-15

The surveillance or monitoring systems used in space station, nuclear power plant and nuclear waste repository, are often equipped with optical fibers to remotely locating expensive camera systems so as to protect them from direct irradiation. Especially in nuclear power plant and nuclear waste repository, irradiation by gamma-ray and beta-ray are most concerned. The effective life-time of such surveillance system may depend on the soundness of the optical fiber because it is the component to be exposed the high intensity of radiation field by purpose. Though the degradation of mechanical properties such as hardness and elasticity may occur but the degradation of the optical property such as spectral transmittance is the most possible cause of the effective life-time limitation. Generally 30 % reduction of light signal transmittance is considered as the life-time threshold point of such optical systems. In this paper, we studied irradiation effects on spectral transparency of various commonly-used optical fibers with high energy electron beam to conveniently simulate the both gamma-ray and beta-ray irradiation situation.

Total and Spectral Solar Irradiance Sensor (TSIS) Project Status

Science.gov (United States)

Carlisle, Candace

2018-01-01

TSIS-1 studies the Sun's energy input to Earth and how solar variability affects climate. TSIS-1 will measure both the total amount of light that falls on Earth, known as the total solar irradiance (TSI), and how that light is distributed among ultraviolet, visible and infrared wavelengths, called solar spectral irradiance (SSI). TSIS-1 will provide the most accurate measurements of sunlight and continue the long-term climate data record. TSIS-1 includes two instruments: the Total Irradiance Monitor (TIM) and the Spectral Irradiance Monitor (SIM), integrated into a single payload on the International Space Station (ISS). The TSIS-1 TIM and SIM instruments are upgraded versions of the two instruments that are flying on the Solar Radiation and Climate Experiment (SORCE) mission launched in January 2003. NASA Goddard's TSIS project responsibilities include project management, system engineering, safety and mission assurance, and engineering oversight for TSIS-1. TSIS-1 was installed on the International Space Station in December 2017. At the end of the 90-day commissioning phase, responsibility for TSIS-1 operations transitions to the Earth Science Mission Operations (ESMO) project at Goddard for its 5-year operations. NASA contracts with the University of Colorado Laboratory for Atmospheric and Space Physics (LASP) for the design, development and testing of TSIS-1, support for ISS integration, science operations of the TSIS-1 instrument, data processing, data evaluation, calibration and delivery to the Goddard Earth Science Data and Information Services Center (GES DISC).

Studying the destruction of various fluoropolymers caused by gamma - irradiation and MeV protons

International Nuclear Information System (INIS)

Allayarov, S.R.; Ol'khov, Yu.A.; Gordon, D.A.; Muntele, C.I.; Muntele, I.C.; Ila, D.; Dixon, D.A.; Kispert, L.D.; Nikolskij, V.G.

2007-01-01

While fluoropolymers are normally used as anti-adherent coating, they are intensely investigated for potential use in various radiation dosimeter applications as well as space technology. In order to understand the discrepancy between high chemical and thermal stability and low radiation stability of various fluoropolymers, we are bombarding them with 1 MeV protons to fluences up to 2·10 15 protons/cm 2 as well as subjected some of them to gamma-irradiation by dose of 10 kGy. During bombardment we are monitoring the emission of chemical species with a residual gas analyzer. Gamma-irradiated samples were tested by radio thermoluminescence method. The results we present here are a good indicator that material damage happens much earlier than 2·10 15 protons/cm 2 and that further work should be addressed at much smaller exposures. Radio thermoluminescence also can be used at small doses of irradiation (10-30 kGy). The thermomechanical curve of radiation-free polyvinyledenefluoride (PVDF) is characteristic for topologically di-block amorphous polymer of quasi-crossing structure. In the temperature range of from 173 K up to 228 K polymer is vitrified. The vitrification temperature of PVDF is 228 K. All molecular-relaxation and quantitative characteristics of PVDF were determined before and after its irradiation by protons. Protons caused significant changes in PVDF. From di-block amorphous it transformed in to amorphous-crystalline structure. An appreciable influence of dose at proton irradiation of polymer was revealed both on topological level and on molecular-relaxation one. (authors)

Biophysical studies of irradiated thymocytes. 1. Surface changes

Energy Technology Data Exchange (ETDEWEB)

Sungurov, A Yu; Tokalov, S V; Petrov, Yu P; Sharlaeva, T M

1985-08-15

In order to study postirradiation changes in thymus lymphocyte surface, a number of biophysical analytical methods was used: the cell two-partition method, the physical adhesion method, fluorescence intensity and binding parameters of negatively charged ANS probe. Reduction of cell distribution factor in two-phase system and adhesion of thymocytes to cotton 1 hour after irradiation, as well as abrupt change in parameters of binding the probe in the interval of 3-4 hours after X-ray irradiation at the dose of 4 Gy are demonstrated.

Conceptual design for real time monitoring of electron microbeam

International Nuclear Information System (INIS)

Kim, Ji Seok; Kim, Hyun Ki; Jang, Mee; Choi, Chang Woon; Sun, Gwang Min; Lee, Jai Ki

2008-01-01

It is recognized that the microbeam is powerful system to understand the interaction of ionizing radiation with cells. Especially, electron microbeam system is useful to investigate the effect of low-LET radiation for cells. Electron microbeam has been developed in KIRAMS. It can irradiate the small volume in cell level by collimator and electromagnetic field and give local dose to individual cell by controlling the number of electrons. When the electron microbeam irradiates the individual cell, however, there is a possibility to change the current and intended trajectory of electron beam. Because this possibility introduces the uncertainty of dose, it is necessary to monitor the trajectory and current of electron beam. This study deals with development of real time monitoring device to confirm beam quality and to control if necessary during experiment. Consequently we designed dual monitoring device to solve various factors. And we optimize the design by simulation. (author)

Models of Solar Irradiance Variations: Current Status Natalie A ...

Indian Academy of Sciences (India)

Abstract. Regular monitoring of solar irradiance has been carried out since 1978 to show that solar total and spectral irradiance varies at different time scales. Whereas variations on time scales of minutes to hours are due to solar oscillations and granulation, variations on longer time scales are driven by the evolution of the ...

Solar ultraviolet irradiance measurements, instrumentation, intercomparisons and interpretations

International Nuclear Information System (INIS)

Thorseth, Trond Morten

2000-01-01

The thesis reports studies of stabile instruments that are capable of detecting small alterations in ultraviolet irradiation over a long period. A central theme in the work has been to improve the measuring systems for continuous research based monitoring of natural variations in the ultraviolet irradiation from the sun. Methods for controlling the stability and continually secure the quality of the collected data. The causes of measuring errors are mapped and methods for the correction of collected data are developed. The methods and measuring systems for collecting the data have been adapted to the Norwegian climate and geography. The work has lead to an increased understanding of the natural variation in the ultraviolet radiation from the sun and what factors in the atmosphere that influences the process. The collected data and the developed methods for the quality control have increased the understanding of the ultraviolet irradiation climate in Europe

Solar ultraviolet irradiance measurements, instrumentation, intercomparisons and interpretations

Energy Technology Data Exchange (ETDEWEB)

Thorseth, Trond Morten

2000-07-01

The thesis reports studies of stabile instruments that are capable of detecting small alterations in ultraviolet irradiation over a long period. A central theme in the work has been to improve the measuring systems for continuous research based monitoring of natural variations in the ultraviolet irradiation from the sun. Methods for controlling the stability and continually secure the quality of the collected data. The causes of measuring errors are mapped and methods for the correction of collected data are developed. The methods and measuring systems for collecting the data have been adapted to the Norwegian climate and geography. The work has lead to an increased understanding of the natural variation in the ultraviolet radiation from the sun and what factors in the atmosphere that influences the process. The collected data and the developed methods for the quality control have increased the understanding of the ultraviolet irradiation climate in Europe.

About the study of irradiation effects on in-core instrumentation

International Nuclear Information System (INIS)

Angelino, G.

1972-01-01

The knowledge of in-core instrumentation performances is a very important item when irradiations of technological interest are concerned. When measurement of small changes in mechanical or thermal properties is of major importance, the effect of neutron and gamma irradiation on various transducers must be thoroughly evaluated. A rig mock-up was irradiated in the Triga Mark II Reactor of the Pavia University to assess the possibility of carrying out a study on irradiation effects on in-core instrumentation. Data on neutron flux distribution and γ-heating effect were collected from this preliminary experiment; at the same time a complete check was performed on rig assembling procedure, on the behaviour under operating conditions, and on the reactor loading and unloading operations. (author)

Detection of Listeria species in Gamma irradiated Fishes during Storage periods

International Nuclear Information System (INIS)

Mohamed, W.S.

2011-01-01

This investigation was carried out to detect the post irradiation recovery and growth of Listeria species encountered in frozen whole Tilapia fishes ,Tilapia fillet and frozen Hamour fillets fishes (-18 degree C) irradiated at 1, 2, 2.5 and 3 kGy. The pathogen was eliminated at a dose of 2.5 kGy of gamma radiation. The presence of the microorganism was monitored for sex months on appropriate selective media. The ability of recovery of the organism from irradiation damage was not influenced by the kind of fish. No increased counts of the organism in irradiated fishes at 2.5 kGy of gamma radiation was noticed during 6 months of freezing storage at -18 degree C. This study also aimed to evaluate the effect of different enrichment procedures on the detection of Listeria species in fishes

An AES Study of the Room Temperature Surface Conditioning of Technological Metal Surfaces by Electron Irradiation

CERN Document Server

Scheuerlein, C; Taborelli, M; Brown, A; Baker, M A

2002-01-01

The modifications to technological copper and niobium surfaces induced by 2.5 keV electron irradiation have been investigated in the context of the conditioning process occurring in particle accelerator ultra high vacuum systems. Changes in the elemental surface composition have been found using Scanning Auger Microscopy (SAM) by monitoring the carbon, oxygen and metal Auger peak intensities as a function of electron irradiation in the dose range 10-6 to 10-2 C mm-2. The surface analysis results are compared with electron dose dependent secondary electron and electron stimulated desorption yield measurements. Initially the electron irradiation causes a surface cleaning through electron stimulated desorption, in particular of hydrogen. During this period both the electron stimulated desorption and secondary electron yield decrease as a function of electron dose. When the electron dose exceeds 10-4 C mm-2 electron stimulated desorption yields are reduced by several orders of magnitude and the electron beam indu...

Irradiation of carbon nanotubes with carbon projectiles: A molecular dynamics study

Energy Technology Data Exchange (ETDEWEB)

Denton, Cristian D. [Departamento de Fisica Aplicada, Universidad de Alicante, 03080 Alicante (Spain); Heredia-Avalos, Santiago; Moreno-Marin, Juan Carlos [Departamento de Fisica, Ingenieria de Sistemas y Teoria de la Senal, Universidad de Alicante, 03080 Alicante (Spain)

2013-04-15

The irradiation of carbon based nanostructures with ions and electrons has been shown to be an appropriate tool to tailor their properties. The defects induced in the nanostructures during irradiation are able to modify their mechanical and electronic properties. Here we simulate the irradiation of carbon nanotubes with carbon ions using a molecular dynamics code. We use the Tersoff potential joined smoothly to the Universal Ziegler-Biersack-Littmark potential at short distances. We study the number of defects produced after irradiation with a single carbon ion finding a saturation with its energy at {proportional_to} 3 keV. We observe, after continuum irradiation with low energy ions, the formation of bumps in the irradiated region. For larger energy ions we find that the diameter of the nanotube shrinks as shown in previous works. (copyright 2013 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

Irradiation combined with SU5416: Microvascular changes and growth delay in a human xenograft glioblastoma tumor line

International Nuclear Information System (INIS)

Schuuring, Janneke; Bussink, Johan; Bernsen, Hans; Peeters, Wenny; Kogel, Albert J. van der

2005-01-01

Purpose: The combination of irradiation and the antiangiogenic compound SU5416 was tested and compared with irradiation alone in a human glioblastoma tumor line xenografted in nude mice. The aim of this study was to monitor microenvironmental changes and growth delay. Methods and materials: A human glioblastoma xenograft tumor line was implanted in nude mice. Irradiations consisted of 10 Gy or 20 Gy with and without SU5416. Several microenvironmental parameters (tumor cell hypoxia, tumor blood perfusion, vascular volume, and microvascular density) were analyzed after imunohistochemical staining. Tumor growth delay was monitored for up to 200 days after treatment. Results: SU5416, when combined with irradiation, has an additive effect over treatment with irradiation alone. Analysis of the tumor microenvironment showed a decreased vascular density during treatment with SU5416. In tumors regrowing after reaching only a partial remission, vascular characteristics normalized shortly after cessation of SU5416. However, in tumors regrowing after reaching a complete remission, permanent microenvironmental changes and an increase of tumor necrosis with a subsequent slower tumor regrowth was found. Conclusions: Permanent vascular changes were seen after combined treatment resulting in complete remission. Antiangiogenic treatment with SU5416 when combined with irradiation has an additive effect over treatment with irradiation or antiangiogenic treatment alone

Monte Carlo studies of the Portuguese gamma irradiation facility. The irradiator geometry and its influence on process parameters

International Nuclear Information System (INIS)

Oliveira, C.; Ferreira, L.; Salgado, J.

2001-01-01

The paper describes a Monte Carlo study of dose distributions, minimum dose and uniformity ratio for the Portuguese Gamma Irradiation Facility. These process parameters are calculated using the MCNP code for several irradiator geometries. The comparison of the simulated results with the experimental results carried out using Amber Perspex dosimeters in a routine process of the gamma facility for a given material composition and density reveals good agreement. The results already obtained allow to conclude that the dose uniformity is not very sensitive to the irradiator geometry for density value ρ = 0.1 and for a dynamic process. (orig.)

Pilotscale studies of dried fish irradiation. Part of a coordinated programme in Asian Regional Cooperative Project on Food Irradiation

International Nuclear Information System (INIS)

Maha, M.

1983-03-01

Pilot scale experiments on irradiation of semi-dried mackerel with regard to shelf-life extension, packaging, transportation and cost-analysis were carried out. The results showed that dipping mackerel in saturated brine for 5 hours and then soaking it in 2% potassium sorbate before sun-drying to approximately 40% moisture content produced a good quality product. Sorbate treatment was effective in controlling mould growth while irradiation with 2 kGy was effective in reducing the bacterial load. Carton boxes were found most suitable as packaging material for irradiated dried fish from the point of view of strength, convenience for irradiation and better dose uniformity ratio than polypropylene bags which have ununiform configuration. Irradiation with doses up to 10 kGy has no significant effect on physical properties of the packaging materials tested. Carton boxes of 20 kg capacity provided with strapping bands are durable for land or sea transportation of dried fish. A radiation dose of 0.5 kGy was sufficient to control insect damage and reduce mould growth on dried fish. Irradiated dried fish can be marketed for 3-4 months at ambient conditions in Jakarta. Small scale consumer studies of irradiated samples using employees of the institute showed no negative reactions. Using the small pilot irradiator at CAIR and assuming 1 kGy minimum dose for dried fish, the total cost of irradiation and packaging was estimated to be approximately 10 U.S. cents/kg of fish, which is about 2-3% of the cost of the product

Experience with a pilot plant for the irradiation of sewage sludge: Bacteriological and parasitological studies after irradiation

International Nuclear Information System (INIS)

Wizigmann, I.; Wuersching, F.

1975-01-01

Comparative bacteriological studies of sewage sludge in a sewage plant have demonstrated that mechanical-biological sewage treatment reduced the total bacterial count and those of Enterococces by 2 log and the Enterobacteriaceae by 3-4 log. Frequently Salmonella could be isolated from sewage sludge. A further reduction of viable micro-organisms could be achieved by irradiation of sewage sludge ( 60 Co, gamma-radiation, 260 krad, 210 min). This reduction amounted to an average of 2 log with Enterococces and total bacterial count, and to 5 log with Enterobacteriaceae. Out of 40 samples investigated after irradiation, two contained Salmonella. The hygienic effects of the irradiation unit were demonstrated by means of a model experiment with bacterial pure cultures. Micro-organisms of different species as well as strains of the same species differ in their sensitivity to irradiation. Parasitological experiments with eggs of Ascaris suum were carried out to test the inhibitory or killing ability of the gamma rays on the developing stages of parasites

Transportation and storage studies on irradiated Alphonso mangoes

International Nuclear Information System (INIS)

Farkas, J.; Dharkar, S.D.; Sreenivasan, A.

1972-01-01

Control as well as skin coated (6% ''Myvacet'') and/or irradiated (25 to 35 krad) mangoes were packed in baskets in dry paddy straw and shipped by rail. After a storage at a temperature of 25 to 32 0 C for a period of 8 days, the baskets were shipped back. After receipt in the laboratory the fruits were kept under observation for 5 more days and then scored for ripening and marketability as assessed by appearance, skin gloss and typical flavour. 100 per cent of fruits skin-coated and irradiated were marketable at the end of the experiment. None of the unirradiated control fruits were saleable by this time, while 66%, of the irradiated fruits were in acceptable condition. In further experiments one dozen mangoes each from control, irradiated and skin-coated and irradiated groups were wrapped individually in tissue paper and packed tightly in a plyweed box. This consignment was air-lifted from Bombay to Budapest, a distance of about 5600 kilometers. The time interval between irradiation and their receipt in Hungary was 4 days. The mangoes were assessed for their storage characteristics by various parameters that included physiological loss in weight, puncture resistance of the skin, pulp texture, carotenoids, acidity and organoleptic attributes, at various periods during storage. It was found that ripening and senescence are strikingly delayed in mangoes by skin-coating and radiation treatment. The treated mangoes retained their skin-resistance while the disappearance of chlorophyl and formation of carotenoids were substantially delayed. Weight loss in storage was lower and reduction of acidity and formation of sugars in the fruit flesh took place later. Organoleptically, the fruits subjected to the combination treatment were good. These studies point to the feasibility of the combination treatment in prolonging the shelf life of fruits significantly to enable their transport to distant countries. (F.G.)

A study on the irradiation effect of reactor materials using a cyclotron

Energy Technology Data Exchange (ETDEWEB)

Hong, Joon Hwa; Ji, Se Hwan; Kang, Yung Hwan; Park, Duk Keun; Park, Jong Man; Lee, Bong Sang; Oh, Jong Myung [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of)

1994-12-01

The objectives of the present study are to develop the simulation techniques of neutron irradiation through ion irradiation using a Cyclotron and small specimen techniques and to evaluate radiation effects of reactor materials. Effects of proton or neutron irradiation on domestic 12Cr-1MoV and SA508-3 steels were evaluated by small scale specimen test techniques, i.e, small punch and miniaturized tensile test. In order to study the radiation damage mechanism, irradiation effects of the steels were investigated by means of property change tests such as microstructure, physical and thermal properties. Feasibility study on application of a magnetic non-destructive methods to evaluate radiation effects on RPV materials was performed. 109 figs, 12 tabs, 102 refs. (Author).

A study on the irradiation effect of reactor materials using a cyclotron

International Nuclear Information System (INIS)

Hong, Joon Hwa; Ji, Se Hwan; Kang, Yung Hwan; Park, Duk Keun; Park, Jong Man; Lee, Bong Sang; Oh, Jong Myung

1994-12-01

The objectives of the present study are to develop the simulation techniques of neutron irradiation through ion irradiation using a Cyclotron and small specimen techniques and to evaluate radiation effects of reactor materials. Effects of proton or neutron irradiation on domestic 12Cr-1MoV and SA508-3 steels were evaluated by small scale specimen test techniques, i.e, small punch and miniaturized tensile test. In order to study the radiation damage mechanism, irradiation effects of the steels were investigated by means of property change tests such as microstructure, physical and thermal properties. Feasibility study on application of a magnetic non-destructive methods to evaluate radiation effects on RPV materials was performed. 109 figs, 12 tabs, 102 refs. (Author)

Swedish studies on irradiation effect in structural materials

Energy Technology Data Exchange (ETDEWEB)

Grounes, M; Myers, H P

1962-12-15

A brief description of work in hand at AB Atomenergi concerning the effects of neutron irradiation on structural materials is given. Some recent data is listed for the following pressure vessel steels 2103/R3 as used in the Aagesta reactor, SIS 142103, NO345, Fortiweld and weld metal OK 54 P. Zircaloy-2 has been studied regarding the combined effects of neutron irradiation and hydrogen content on tensile properties. The difficulties associated with determination of neutron dose and the correlation of damage with dose and neutron energy spectrum are discussed.

Swedish studies on irradiation effect in structural materials

International Nuclear Information System (INIS)

Grounes, M.; Myers, H.P.

1962-12-01

A brief description of work in hand at AB Atomenergi concerning the effects of neutron irradiation on structural materials is given. Some recent data is listed for the following pressure vessel steels 2103/R3 as used in the Aagesta reactor, SIS 142103, NO345, Fortiweld and weld metal OK 54 P. Zircaloy-2 has been studied regarding the combined effects of neutron irradiation and hydrogen content on tensile properties. The difficulties associated with determination of neutron dose and the correlation of damage with dose and neutron energy spectrum are discussed

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

High-temperature annealing of proton irradiated beryllium – A dilatometry-based study

Energy Technology Data Exchange (ETDEWEB)

Simos, Nikolaos, E-mail: simos@bnl.gov [Brookhaven National Laboratory, Upton, NY, 11973 (United States); Elbakhshwan, Mohamed; Zhong, Zhong; Ghose, Sanjit [Brookhaven National Laboratory, Upton, NY, 11973 (United States); Savkliyildiz, Ilyas [Rutgers University (United States)

2016-08-15

S−200 F grade beryllium has been irradiated with 160 MeV protons up to 1.2 10{sup 20} cm{sup −2} peak fluence and irradiation temperatures in the range of 100–200 °C. To address the effect of proton irradiation on dimensional stability, an important parameter in its consideration in fusion reactor applications, and to simulate high temperature irradiation conditions, multi-stage annealing using high precision dilatometry to temperatures up to 740 °C were conducted in air. X-ray diffraction studies were also performed to compliment the macroscopic thermal study and offer a microscopic view of the irradiation effects on the crystal lattice. The primary objective was to qualify the competing dimensional change processes occurring at elevated temperatures namely manufacturing defect annealing, lattice parameter recovery, transmutation {sup 4}He and {sup 3}H diffusion and swelling and oxidation kinetics. Further, quantification of the effect of irradiation dose and annealing temperature and duration on dimensional changes is sought. The study revealed the presence of manufacturing porosity in the beryllium grade, the oxidation acceleration effect of irradiation including the discontinuous character of oxidation advancement, the effect of annealing duration on the recovery of lattice parameters recovery and the triggering temperature for transmutation gas diffusion leading to swelling.

Study of microstructural evolutions of the 6061-T6 aluminium alloy under irradiation

International Nuclear Information System (INIS)

Flament, Camille

2015-01-01

The 6061-T6 Aluminium alloy, whose microstructure contains Al(Fe,Mn,Cr)Si dispersoids and hardening needle-shaped β'' precipitates (Mg, Si), has been chosen as the structural material for the core vessel of the Material Testing Jules Horowitz Nuclear Reactor. Because it will be submitted to high neutron flux at a temperature around 50 C, it is necessary to study microstructural evolutions induced by irradiation and especially the stability of the second phase particles. In this work, an analytical study by in-situ and ex-situ electron and ion irradiations has been performed, as well as a study under neutron irradiation. The precipitate characterization by Transmission Electron Microscopy demonstrates that Al(Fe,Mn,Cr)Si dispersoids are driven under irradiation towards their equilibrium configuration, consisting of a core/shell structure, enhanced by irradiation, with a (Fe, Mn) enriched core surrounded by a Cr-enriched shell. In contrast, the (Mg,Si) β'' precipitates are destabilized by irradiation. They dissolve under ion irradiation in favor of a new precipitation of (Mg,Si,Cu,Cr,Al) rich clusters resulting in an increase of the alloy's hardness. β'' precipitates tend towards a transformation to cubic precipitates under neutron irradiation. (author) [fr

Deterioration in lung function following hemithorax irradiation for pleural mesothelioma

International Nuclear Information System (INIS)

Maasilta, P.

1991-01-01

Thirty-four patients receiving high-dose hemithorax irradiation as part of the treatment for pleural mesothelioma were studied with regard to changes in lung function following irradiation, and these changes were correlated with the radiologically-assessed lung injury. The latter was scored from 0 to 500 and found to be severe by 6 months (mean score 360), very severe by 9 months (mean score 430), and nearly total by 12 months (mean score 480) after treatment. Forced vital capacity and diffusing capacity both showed a significant decline at 1.5-2 months following the end of radiotherapy and thereafter up to the end of the 1 year follow-up period. Neither of these variables could be correlated consistently with the radiologically-assessed changes. Hypoxemia and pathological physiological shunting increased transiently 1-2 months after irradiation in 2 of the 6 patients monitored. The observed radiologically-assessed final effects of high-dose hemithorax irradiation are compatible with a total loss of lung function on the irradiated side. Before this form of treatment is used, lung function should be evaluated as for pneumonectomy

An ultrastructural and irradiation study of diffuse and localised kinetochore

International Nuclear Information System (INIS)

Bokhari, F.S.

1979-05-01

An electron microscope study of plant types Luzula nivea and Cyperus eragrostis with diffuse kinetochores and Crepis neglecta with localised kinetochore showed that Luzula has a rather different kinetochore organisation from Cyperus, with features approaching the localised type of Crepis. These studies included an examination of the ultrastructure of the kinetochore at metaphase at low magnification in control and irradiated material of Luzula; the chromosomal ultrastructure at high magnification at interphase and all stages of mitosis in Luzula, Cyperus and Crepis; and the ultrastructure of the nucleolus in Luzula, Cyperus and Crepis. Light microscopic studies were also performed showing the effects of irradiation on first mitotic division in Cyperus, Luzula and Crepis, mitotic aberrations in Cyperus and Crepis and meiosis in Cyperus. Finally, the survival with the diffuse as opposed to the localised kinetochore in M 1 and M 2 generations following seed irradiation was studied. (U.K.)

Study of irradiation induced defects and phase instability in β phase of Zr Excel alloy with in-situ heavy ion irradiation

International Nuclear Information System (INIS)

Yu, H.; Yao, Z.; Kirk, M.A.; Daymond, M.R.

2015-01-01

In situ heavy ion irradiation with 1 MeV Kr"2"+ was carried out to study irradiation induced phase change and atomic lattice defects in theβ phase of Zr Excel alloy. No decomposition of β-Zr was observed under irradiation at either 200 "oC or 450 "oC. However, ω-Zr particles experienced shape change and shrinkage associated enrichment of Fe in the β/ω interface at 200 "oC irradiation but not at 450 "oC. The defect evolution in the β-phase was examined with single phase Zr-20Nb alloy. It was found that dislocation loops with Burgers vector 1/2 and both present in β-Zr under room temperature irradiation. (author)

X- and Q-band EPR studies on fine powders of irradiated plants. New approach for detection of their radiation history by using Q-band EPR spectrometry

International Nuclear Information System (INIS)

Yordanov, Nicola D.; Aleksieva, Katerina

2004-01-01

X- and Q-band EPR studies after γ-irradiation of some dry spices and aromatic herbs are reported. Before irradiation all samples show only one singlet line in X-band EPR, whereas the Q-band EPR spectrum of the same samples is a superposition of two individual spectra--one corresponding to the above EPR signal, with an anisotropic spectrum, and a second one consisting of six lines due to the Mn 2+ naturally present in plants. The radiation induced EPR signal due to cellulose free radicals was not detected after γ-irradiation, but only the increase of the natural signal present before the irradiation. The fading kinetic of this EPR signal was monitored in three cases--when samples were kept in plastic bags without any special conditioning after irradiation, when samples were covered with paraffin before irradiation and when samples were dried at 60 deg. C for 1 h before irradiation. The studies show that stability of radiation induced EPR signals decreases in the order of: paraffin covered > heated before irradiation > kept at room conditions. The two EPR spectra in the Q-band--one with radiation dependent intensity and a second due to Mn 2+ , which is radiation independent allow identification of previous radiation treatment based on the fact that Mn 2+ quantity in the sample is constant whereas the quantity of radiation-induced free radicals is temperature dependent. It was found that for irradiated samples the ratio between EPR intensity of the free radicals and that of Mn 2+ before and after heating decreases with 50-60% whereas for non-irradiated samples it is ca. 10-15%

Low cycle fatigue behaviour of neutron irradiated copper alloys at 250 and 350 deg. C

DEFF Research Database (Denmark)

Singh, B.N.; Stubbins, J.F.; Toft, P.

2000-01-01

V) to influence levels of 1.0 - 1.5 x 1024 n/m2 (E> 1 MeV) at 250 and 350 deg. C. These irradiations were carried out in temperature controlled rigs where the irradiation temperature was monitored and controlledcontinuously throughout the whole irradiation experiment. Both unirradiated and irradiated speciments...

Experimental study of selective irradiation to the kidneys

Energy Technology Data Exchange (ETDEWEB)

Nishimori, I; Tsuda, N; Moriyama, N; Miyagawa, N; Fuzikawa, K [Nagasaki Univ. (Japan). School of Medicine

1976-03-01

In order to examine the effects of a massive irradiation on the kidney, 4,000 R of x-ray was irradiated to both kidneys of rats. Renal atrophy was observed 1, 2 and 3 weeks after the irradiation, and this alteration was severe especially in the left kidney. Light microscopic examination revealed dilatation of the renal tubules, swelling of the tubular epithelial cells, granular degeneration and cylindrialization 1 and 2 weeks after the irradiation. However, there was no remarkable alteration in the glomeruli. Lobulation of the glomeruli appeared in addition to alteration in the renal tubules 3 weeks after the irradiation. Hyalinosis of the glomeruli, degerenation of the renal tubules, cylindrialization, thickening of the vascular wall, fibroid necrosis, and proliferation of the interstitial cells appeared 25 weeks after the irradiation. Electron microscopic examination revealed reduction of the nuclei in the tubular epithelial cells, differentiation and thickening of dense bodies and the basement membrane, dilatation of capillaries and swelling of the endothelial cells 1 week after the irradiation. Obliteration of capillaries of the glomeruli, thickening of the basement membrane, deposit of collagen and swelling of the epithelial cells were observed 25 weeks after the irradiation. Cellular infiltration was observed in the interstitial tissue. The increase of blood pressure, vascular lesion and hyalinosis of the glomeruli, which appeased 25 weeks after the irradiation, are considered to be caused secondarily by an increase of the interstitial cells.

Fabrication and mount of a multisource irradiation systems

International Nuclear Information System (INIS)

Mariano-Heredia, E.

1990-01-01

Conception of this equipment was born of the necessity for a system suitalbe for optimizing the methods employed up to the present in ININ, for calibrating portalbe gamma radiation monitors for radiological protection of the need for a national level reference laboratory. The equipment parts are: a multisource irradiator, a system for the transport and positioning of radiation monitors, an aerial conveyor ANS a control panel. The multisource irradiator, which is shielded container, houses five Cs-137 and Co-60 different activity radiative sources. The transport and positioning radiation monitor system places the monitors for calibration at the required distance and height. The instrument source distance can be selected from the control panel. The instrument source distance and detector readings can be verified by means of a closed TV circuit. The activity of the radiation sources, using varying combinations of instrument source distances, has been characterized for each of the radiative sources and all the calibration parameters of the radiation beam central axis are known to a precision of within 3.0 % error. (Author)

EPR study on tomatoes before and after gamma-irradiation

International Nuclear Information System (INIS)

Aleksieva, K.; Georgieva, L.; Tzvetkova, E.; Yordanov, N.D.

2009-01-01

The results from the EPR studies on fresh, air-dried and lyophilized tomato samples before and after gamma-irradiation are reported. Before irradiation fresh and air-dried tomatoes exhibit one singlet EPR line characterized with common g-factor of 2.0048±0.0005, whereas freeze-dried tomato does not show any EPR spectrum. After irradiation, a typical 'cellulose-like' triplet EPR spectrum appears in all samples, attributed to cellulose free radicals, generated by gamma-irradiation. It consists of intense central line with g=2.0048±0.0005 and two weak satellite lines separated ca. 3 mT left and right of it. In air-dried and lyophilized tomatoes the 'cellulose-like' EPR spectrum is superimposed by an additional partly resolved carbohydrate spectrum. Fading measurements of the radiation-induced EPR signals indicate that the intensity of the EPR spectra of air-dried and freeze-dried tomato are reduced to about 50% after 50 days, whereas those of fresh irradiated tomatoes kept at 4 o C fade completely in 15 days. The reported results unambiguously show that the presence of two satellite lines in the EPR 'cellulose-like' spectra of tomato samples can be used for identification of radiation processing.

Study on prediction model of irradiation embrittlement for reactor pressure vessel steel

International Nuclear Information System (INIS)

Wang Rongshan; Xu Chaoliang; Huang Ping; Liu Xiangbing; Ren Ai; Chen Jun; Li Chengliang

2014-01-01

The study on prediction model of irradiation embrittlement for reactor pres- sure vessel (RPV) steel is an important method for long term operation. According to the deep analysis of the previous prediction models developed worldwide, the drawbacks of these models were given and a new irradiation embrittlement prediction model PMIE-2012 was developed. A corresponding reliability assessment was carried out by irradiation surveillance data. The assessment results show that the PMIE-2012 have a high reliability and accuracy on irradiation embrittlement prediction. (authors)

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

Experimental study associated to irradiation of FBR structural material, (4)

International Nuclear Information System (INIS)

1976-01-01

The study presents one of the bases to evaluate the results of the post-irradiation tests to conduct the thermal control tests related to the second JMTR irradiation (70M-61P) of the demestic austenitic stainless steels for the structural material of the FBR performed by Power Reactor and Nuclear Fuel Development Corporation. The thermal control specimens were given the temperature history which simulated that of the irradiation temperature in vacuum by the electrical furnance, and then the tensile, fatigue and Charpy impact tests were performed. The changes of the material properties caused by the thermal history were investigated. (auth.)

Crystallographic study of the tempering by irradiation of cold-worked uranium (1960); Etude cristallographique du revenu de l'uranium ecroui par irradiation (1960)

Energy Technology Data Exchange (ETDEWEB)

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

1960-07-01

We have studied the phenomenon of the tempering of cold-worked uranium under the action of irradiation by observing the narrowing of the (114) and (133) X-ray diffraction lines as a function of the irradiation level. Simultaneously we have studied the broadening of the 114 line of a recrystallised uranium as a function of the irradiation level. The irradiation temperature was always less than 60 deg. C. Of these two processes, the first is the fastest. We have observed a saturation of the irradiation tempering for a flux of 10{sup 18} n/cm{sup 2}; we deduce from this the dimensions of the volume perturbed by one fission atom to be 10{sup -17} cm{sup 3}. (author) [French] Nous avons etudie le phenomene de revenu par irradiation d'echantillons d'uranium ecroui, en observant l'affinement des raies de diffraction de rayons X (114) et (133) en fonction du taux d'irradiation. Parallelement nous avons etudie l'elargissement de la raie (114 ) d'un uranium recristallise en fonction du taux d'irradiation. La temperature d'irradiation est toujours restee inferieure a 60 deg. C. De ces deux processus le premier est le plus rapide. Nous avons observe une saturation du revenu par irradiation pour un flux de 10{sup 18} n/cm{sup 2}; on en deduit une valeur du volume de la perturbation creee par un atome de fission egale a 10{sup -17} cm{sup 3}. (auteur)

Comparative study of native and irradiated crotoxin. Biochemical and pharmacological effects

International Nuclear Information System (INIS)

Nascimento, N. do.

1991-01-01

Ionizing radiation is able to detoxify several venoms, including snake venom, without affecting significantly their antigenic and immunogenic properties. In order to elucidate this phenomena, we conceived a comparative biochemical and pharmacological study between native and gamma irradiated (2000Gy) crotoxin, main toxin of south american rattlesnake Crotalus durissus terrificus. Crotoxin was isolated and purified from crude venom by molecular exclusion chromatography, pI precipitation and then irradiated. Immunodiffusion, electrophoresis and gel filtration showed that the molecular integrity was preserved after irradiation with some higher molecular weight aggregate formation and maintenance of its antigenic capacity. The antibodies induced by irradiated toxin had a similar titer to the antibodies induced by native crotoxin; however with higher protective effects in mice. Crotoxin toxicity became 15 times lower after irradiation, as determined by LD sub(50) in mice. Native and irradiated crotoxin biodistribution occurred with a similar general pattern, with renal elimination. In contrast to irradiated crotoxin, the native crotoxin is initially retained in kidneys. A later concentration (2-3hs) occurs in phagocyticmononuclear cells rich organs (liver and spleen) and neural junctions rich organs (muscle and brain). (author)

Studies on mutagenic activity of 60Co γ-ray irradiated rape pollen

International Nuclear Information System (INIS)

He Weishun; Liu Aihua; Lin Shiying; Xiong Xikun

1989-01-01

In the present study on disinfection, the rape pollen was irradiated with 2.5 kGy 60 Co γ-ray. Micronuclei, sister chromatid exchanges (SCE) of bone marrow cells and chromosomal aberrations of meiotic cells in mice were used as an indicater of chromosomal damage to study the mutagenicity of irradiated rape pollen. The results are as follows: (1) The frequency of micronuclei in polychromatic erythrocytes is 2.00 per mille; nucleated cells is 0.8 per mille in control group. In the numbers of polychromatic erythrocytes and nucleated cells with micronuclei, there is no obviously difference in irradiated and unirradiated groups. (2) SCE incidence of control group is 2.01 ± 0.12/cell. No significant difference in the frequency of SCE exists between non-irradiated rape pollen and the control groups. But the frequency of SCE in irradiated rape pollen group (3000 mg/kg/day x 7) is 2.36 ± 0.12/cell; high dose group (6000 mg/kg/day x 7) is 2.96 ± 0.14/cell. In comparison with control group, there is a significant difference. (3) The chromatid breaks, fragments, and univalents in primary spermatocytes have been obseved. The frequencies of chromosomal aberration showed no obviously difference among irradiated and non-irradiated rape pollen groups

Study of irradiation induced defects and phase instability in β phase of Zr Excel alloy with in-situ heavy ion irradiation

Energy Technology Data Exchange (ETDEWEB)

Yu, H.; Yao, Z., E-mail: 12hy1@queensu.ca [Queen' s University, Department of Mechanical and Materials Engineering, Kingston, ON (Canada); Kirk, M.A. [Argonne National Laboratory, Materials Science Division, Argonne, IL (United States); Daymond, M.R. [Queen' s University, Department of Mechanical and Materials Engineering, Kingston, ON (Canada)

2015-07-01

In situ heavy ion irradiation with 1 MeV Kr{sup 2+} was carried out to study irradiation induced phase change and atomic lattice defects in theβ phase of Zr Excel alloy. No decomposition of β-Zr was observed under irradiation at either 200 {sup o}C or 450 {sup o}C. However, ω-Zr particles experienced shape change and shrinkage associated enrichment of Fe in the β/ω interface at 200 {sup o}C irradiation but not at 450 {sup o}C. The defect evolution in the β-phase was examined with single phase Zr-20Nb alloy. It was found that dislocation loops with Burgers vector 1/2<111> and <001> both present in β-Zr under room temperature irradiation. (author)

Integrated studies of irradiated Philippine mangoes. Part of coordinated programme in Asian Regional Cooperative Project on Food Irradiation

International Nuclear Information System (INIS)

Manalo, J.A.

1985-09-01

Effects of combined treatment of hot water dip (50 deg. C for 5 min.) and irradiation (0.65 kGy) on technological and sensory qualities of Carabao mangoes were investigated. Mangoes that ripen to the yellow green stage during transport may be subjected to irradiation of combined hot water dip at 50 deg. C for 5 minutes and irradiation at 0.65 kGy. When stored at the low temperature of 12-15 deg. C, shelf life is extended further. Time interval between hot water dip and irradiation must be as short as possible and fruits must be stored at ambient temperature prior to irradiation to prevent discoloration. Shelf life studies show that green fruits subjected to combined treatment and stored at ambient temperature extended shelf life by 6 days, 50% of yellow green mangoes subjected to combined treatment exhibited shelf life extension by four days. Mangoes stored at cold temperature, whether immediately after irradiation or after ripening showed considerable reduction in bacterial decay, regardless of fruit maturity, thus extending their shelf life considerably. Results of sensory evaluation showed no marked differences in color, aroma, appearance, and acceptability were observed by the taste panelists and although controls were always rated higher than the treated samples, scores higher than 5 given to the treated samples showed that they were also generally acceptable

Study of homing patterns of x-irradiated murine lymphoid cells

International Nuclear Information System (INIS)

Crouse, D.A.

1974-01-01

Effects of in vitro x-ray exposure of murine lymphoid cells on their subsequent in vivo homing patterns were studied. The homing of lymphoid cells to various tissues and organs was followed by using radio-labeled cell preparations or by following the distribution of cells with a specific immunological memory. X irradiation of 51 Cr-labeled spleen, lymph node, bone marrow, or thymus cells was found to significantly alter their subsequent in vivo distribution. Irradiated cells demonstrated an increased distribution to the liver and a significantly lower retention in the lungs. Cells going to the lymph nodes of Peyer's patches showed a significant exposure dependent decrease in homing following irradiation. Irradiated lymph node cells homed in greater numbers to the spleen and bone marrow, while irradiated cells from other sources showed a decrease or no change indistribution to the same tissues. Lymph node cell suspensions from dinitrophenyl-bovine gamma globulin (DNP-BGG) immune LBN rats were prepared, irradiated (0 and 200 R) and injected into intermediate (LBN) hosts and controls. Irradiated memory cells provided a secondary antibody response, which was delayed but not suppressed when compared to unirradiated cells. Alteration in homing of lymphocytes caused by various physical and chemical agents was a result of effects on cell membrane characteristics which controlled some aspects of the phenomenon. Radiation (100 to 200 R) may have had a similar effect or it may have resulted in the selective elimination of a population of cells. (U.S.)

Solubility and IR studies of gamma-irradiated arabinoxylan

International Nuclear Information System (INIS)

Ebringerova, A.; Kacurakova, M.; Hromadkova, Z.; Pruzinec, J.

1989-01-01

The structural and solubility changes of a water-insoluble arabinoxylan with a low degree of branching was studied after γ-irradiation by IR spectroscopy and chemical analysis of the polysaccharide and its polymeric fractions. New functional groups like hydroperoxidic, carbonylic and endiolic ones were found after irradiation. The IR spectra shows that the structural changes involved by radiolytic treatment are reflected in the shape of the IR spectra of both polymeric fractions. The ratio of absorbance of the peaks at 1725 and 2920 cm -1 increased with radiation dose. (author) 17 refs.; 2 figs.; 2 tabs

Biochemical studies on irradiated onions, potatoes and mushrooms

International Nuclear Information System (INIS)

Matkovics, B.

1985-01-01

The activities of the antioxidant enzymes: superoxide dismutase, peroxidase and catalase and the quantitative values of some other important components of irradiated foodstuffs were studied. It was found that the activities of the examined antioxidant enzymes and the value of lipid peroxidation vary from species to species, but also depend on the variety within the species. Dynamic changes of the smaller molecules, lasting for various periods of time, can also be well observed following irradiation. This indicates that radiation treatment changes the physiological processes of the examined basic foodstuffs and give rise to new equilibria in these processes. (author)

High-dose irradiation: Wholesomeness of food irradiated with doses above 10 kGy. Report of a joint FAO/IAEA/WHO study group

International Nuclear Information System (INIS)

1999-01-01

This report presents the recommendations of an international group of experts convened by the World Health Organization, in association with the Food and Agriculture Organization of the United Nations and the International Atomic Energy Agency, to consider the implications of food irradiated to doses higher than those recommended in 1980 by the Joint Expert Committee on the Wholesomeness of Irradiated Food. Irradiation ensures the hygienic quality of food and extends shelf-life. The public perception of the safety of food irradiation has generally precluded its widespread use. However, current applications of food irradiation to doses over 10 kGy have been in the development of high-quality shelf-stable convenience foods for specific target groups such as immunosuppressed individuals and those under medical care, astronauts and outdoor enthusiasts. The Study Group reviewed data relating to the toxicological, nutritional, radiation chemical and physical aspects of food irradiated to doses above 10kGy from a wide range and number of studies carried out over the last forty years. This report presents a comprehensive summary, along with references, of the effectiveness and safety of the irradiation process. It concludes that foods treated with doses greater than 10kGy can be considered safe and nutritionally adequate when produced under established Good Manufacturing Practice

Autoradiographic study of gamma-irradiated mouse spleen during primary immune response

International Nuclear Information System (INIS)

Gitsov, L.G.; Kyncheva, L.S.; Burneva, V.G.; Martinova, J.Sh.; Viklichka, S.

1978-01-01

Study on the kinetics of the cells in the mouse spleen during the primary immune response against thymusdependent antigen after sublethal irradiation was carried out. For this purpose the animals were immunized with sheep erythrocytes one day after their irradiation with 700 r gamma rays. On the 5th day after the immunization, tritium labelled thymidine was injected three times at two hourly intervals. Mice were killed two hours after the third injection for preparation of routine histological samples and autoradiographs. Immunized, but not irradiated mice were utilized as controls. Extensive zones of lymphocyte destruction were observed in the spleen of the irradiated mice - accumulation of picnotic lymphocyte nuclei, surrounded by reticulo-histocyte elements. The number of the labelled cells and the intensity of labelled are lower than that of the germinal centres in control animal. There is no marked cell destruction in the periarteriolar zone nor labelled cells, whereas in the controls there is a considerable number of labelled blast cells. In the red pulp of the irradiated animals islands of erythroblasts were found, whereas in the controls - parallely to the erythroblast islands, there are islands of proliferating lymphocytes and plasmocytes. The decrease of lymphocyte number in irradiated mice is connected with their destruction and with the altered lymphocytopoiesis in the red pulp. It is assumed that the observed preservation of the periarteriolar lymphatic sheaths in an expression of a higher radioresistance of the T-cells as compared to the B-cells in the white pulp. This study contributes for elucidation of the irradiation immunosuppressive effect. It points out also that the post-irradiation lymphopaenia is due not only to the cell death but also to the exclusion of part of the T-lymphocytes from the circulation and their selective deposition in the thymus-dependent zones of the peripheral lymphoid organs. (A.B.)

Study of the Effect of Swelling on Irradiation Assisted Stress Corrosion Cracking

Energy Technology Data Exchange (ETDEWEB)

Teysseyre, Sebastien Paul [Idaho National Lab. (INL), Idaho Falls, ID (United States)

2016-09-01

This report describes the methodology used to study the effect of swelling on the crack growth rate of an irradiation-assisted stress corrosion crack that is propagating in highly irradiated stainless steel 304 material irradiated to 33 dpa in the Experimental Breeder Reactor-II. The material selection, specimens design, experimental apparatus and processes are described. The results of the current test are presented.

Contribution to the investigation of phase transitions induced by irradiation in insulating crystalline ceramics

International Nuclear Information System (INIS)

Simeone, D.

2003-01-01

The author gives a rather detailed overview of his research activities on the behaviour of ceramics subjected to irradiations by charged or not-charged particles. He reports the development of a new application of low incidence X ray diffraction to assess the evolutions within irradiated solids. Coupling this technique with Raman spectroscopy studies enabled the monitoring of order parameter evolution in these solids. He shows that, in some oxides, irradiation effects entail order-disorder type transitions and, more surprisingly, displacive phase transitions. From this experimental work, he developed a modelling of these phase transitions induced by irradiation. Quantitative data obtained on the evolutions of order parameters enabled these phase transitions to be explained within the frame of the thermodynamics of off-equilibrium phenomena

Experimental studies on anti-oxidants reducing lipid peroxidation of irradiated mice

International Nuclear Information System (INIS)

Du Zeji; Liu Keliang; Su Liaoyuan

1993-08-01

The free radical plays an important role in the irradiation damage. The irradiation damage would be reduced if anti-oxidants is used, because anti-oxidants can scavenge free radicals and suppress lipid peroxidation. In the study, a fluoro-spectrophotometer was used to determine the changes of MDA levels in mice tissues and serum after irradiation and the protective effect of anti-oxidants of Vit E and DMSO on damage caused by free radicals. The results are as follows: (1) The highest MDA level was at 12 to 24 hours after irradiation dose of 3.0 Gy. (2) The MDA level is increasing with the increasing of irradiation dose. It means the MDA level can indicate the extent of irradiation damage. (3) Both Vit E and DMSO had a powerful effect on reducing MDA level, but the effect of DMSO was stronger than Vit E. The optimum doses of them were 0.25 mg/g body weight and 10 mg/g body weight respectively. (4) The best effect obtained was to use Vit E and DMSO simultaneously

In vivo dosimetry study of semi-conductors EPD-20 in total body irradiation technique; Etude de la dosimetrie in vivo par semi-conducteurs EPD-20 dans les conditions de l'irradiation corporelle totale

Energy Technology Data Exchange (ETDEWEB)

Besbes, M.; Kochbati, L.; Ben Abdennabi, A.; Abdessaied, S.; Salem, L.; Frikha, H.; Nasr Ben Ammar, C.; Hentati, D.; Gargouri, W.; Messai, T.; Benna, F.; Maalej, M. [Institut Salah-Azaiz, Service de radiotherapie oncologique, Tunis (Tunisia); Mahjoubi, H. [Institut superieur des technologies medicales de Tunis, Dept. de biophysique, Tunis (Tunisia); Farhat, L. [CHU Habib-Bourguiba, Service de radiotherapie oncologique, Sfax (Tunisia)

2010-01-15

Purpose: The objective of this work was the study of in vivo dosimetry performed in a series of 54 patients receiving total body irradiation (T.B.I.) at the Salah-Azaiz Institute of Tunis since 2004. In vivo dosimetry measurements were compared to analytically calculated doses from monitor units delivered. Patients and method: The irradiation was conducted by a linear accelerator (Clinac 1800, Varian, Palo Alto, USA) using nominal X-rays energies of 6 MV and 18 MV, depending on the thickness of the patient at the abdomen. The dose was measured by semi-conductors p-type E.P.D.-20. These diodes were calibrated in advance with an ionization chamber 'P.T.W. Farmer' type of 0.6 cm{sup 3} and were placed on the surface of plexiglas phantom in the same T.B.I. conditions. A study of dosimetric characteristics of semi-conductors E.P.D.-20 was carried out as a function of beam direction and temperature. Afterwards, we conducted a comparative analysis of doses measured using these detectors during irradiation to those calculated retrospectively from monitor units delivered to each patient conditioned by T.B.I.. Results: Experience showed that semi-conductors are sensitive to the angle of beam radiation (0-90 degrees) and the temperature (22-40 Celsius degrees). The maximum variation is respectively 5 and 7%, but in our irradiation conditions these correction factors are less than 1%. The analysis of the results of the in vivo dosimetry had shown that the ratio of the average measured doses and analytically calculated doses at the abdomen, mediastinum, right lung and head are 1.005, 1.007, 1.0135 and 1.008 with a standard deviation 'type A' respectively of 3.04, 2.37, 7.09 et 4.15%. Conclusion: In vivo dosimetry by semi-conductors is in perfect agreement with dosimetry by calculation. However, in vivo dosimetry using semiconductors is the only technique that can reflect the dose actually received instantly by the patient during T.B.I. given the many factors

FTIR studies of swift silicon and oxygen ion irradiated porous silicon

International Nuclear Information System (INIS)

Bhave, Tejashree M.; Hullavarad, S.S.; Bhoraskar, S.V.; Hegde, S.G.; Kanjilal, D.

1999-01-01

Fourier Transform Infrared Spectroscopy has been used to study the bond restructuring in silicon and oxygen irradiated porous silicon. Boron doped p-type (1 1 1) porous silicon was irradiated with 10 MeV silicon and a 14 MeV oxygen ions at different doses ranging between 10 12 and 10 14 ions cm -2 . The yield of PL in porous silicon irradiated samples was observed to increase considerably while in oxygen irradiated samples it was seen to improve only by a small extent for lower doses whereas it decreased for higher doses. The results were interpreted in view of the relative intensities of the absorption peaks associated with O-Si-H and Si-H stretch bonds

A history of study on safety of irradiated foods (2). Clostridium botulinum in irradiated seafood from the reports by the United States Atomic Energy Commission

International Nuclear Information System (INIS)

Miyahara, Makoto

2004-01-01

This review is a part of ''history of study on the wholesomeness of irradiated foods''. Clostridium botulinum in irradiated seafood have been of great concern at the beginning of development of irradiated food. This review describes the studies on Clostridium botulinum by US. Atomic Energy Commission in 1960's with their data and what they recognized it as a risk factor of irradiated foods. In 1999 FAO/IAEA/WHO reported that Clostridium botulinum type A and B spors are apparently the most resistant and thus of great concern in the radiation sterilization of food, whereas the less radiation-resistant type E spores are important in low dose irradiation of foods, particularly fishery products. This review also describes current break-through application by NASA and Canadian irradiator. (author)

Wholesomeness studies on irradiated foods. Past and future research within the Soviet Union

Energy Technology Data Exchange (ETDEWEB)

Zaytsev, A.N.; Shillinger, Yu.I.; Kamaldinova, Z.M.

1975-11-01

The concept of wholesomeness is based on the absence of induced radioactivity, conservation of the nutritive value of food, and absence of toxicological or mutagenic effects. The possible occurrence of Clostridium botulinum toxin in irradiated fish products is discussed. Evaluation of the nutritive value of irradiated food is discussed with regard to proteins and vitamins. Toxicity and mutagenicity studies are described. Feeding studies on the wholesomeness of irradiated food were conducted in the Soviet Union using potatoes, grain, dried fruits, meat, poultry, and fish. The need for further investigations on the biological value of irradiated foods is pointed out. (HLW)

Irradiation of Polystyrene and Polypropylene to study NIH 3T3 fibroblasts adhesion

International Nuclear Information System (INIS)

Arbeitman, C.R.; Grosso, M.F. del; Ibanez, I.; Garcia Bermudez, G.; Duran, H.; Chappa, V.C.; Mazzei, R.; Behar, M.

2010-01-01

When polymers are irradiated with heavy ions new chemical groups are created in a few microns of the material. The irradiation changed the polarity and wettability on the surface so that could enhance the biocompatibility of the modified polymer. The study of chemistry and nanoscale topography of the biomaterial is important in determining its potential applications in medicine and biotechnology, because their strong influence on cell function, adhesion and proliferation. In this study, thin films of Polystyrene and Polypropylene samples were modified by irradiation with low energy ion beams (30-150 keV) and swift heavy ions both with various fluences and energies. The changes were evaluated with different methods. Adhesion of NIH 3T3 fibroblasts onto unirradiated and irradiated surfaces has been studied by in vitro techniques. The correlations between physicochemical properties as a function of different irradiations parameters were compared with cell adhesion on the modified polymer surface.

The ageing kidney: biochemical and morphological study after irradiation

International Nuclear Information System (INIS)

Franciolini, F.; Becciolini, A.; Torcini, G.; Lanini, A.

1982-01-01

The behaviour of some activities of the kidney was studied both in young-adult and in adult rats exposed to an 8-Gy dose of γ-rays and killed at various intervals after irradiation (both in the morning and in the evening). Brush border and lysosomal enzymes did not show marked differences among control rats of the same age even if adult animals showed levels of maltase, alkaline phosphatase and LAP activities higher than the young-adult group. Moreover, irradiation did not induce typical modifications of the same enzyme activities in young-adult and adult rats. Adult animals showed a reduction in the brush border enzyme activities at 120 hours after irradiation while, at the same interval, lysosomal activities underwent an increase both in young and in adult animals. (orig.) [de

Kinetic study of UV-irradiated amorphous sulfur by EPR spectroscopy

International Nuclear Information System (INIS)

El Mkami, H.; Smith, G.M.

2005-01-01

Electron paramagnetic resonance (EPR) spectroscopy is used to investigate UV-irradiation damage in amorphous sulfur by examining post-irradiation kinetics as a function of UV-exposure time. The kinetic study is described by first-order concurrent reactions where the sulfur, as reactant, undergoes two parallel processes leading to the formation of two distinct defects called S 1 * and S 2 *. The temperature dependence of the EPR intensities of the signals, related to these defects, is used in the kinetic study

Topography of π--irradiated volumes

International Nuclear Information System (INIS)

Bueche, G.

1976-02-01

The charge exchange reaction π - p → π 0 n and the radiative capture of negative pions π - p → nγ can be used to control the range of π - in matter like human tissue. The calculations reported in this paper demonstrate that it is possible to construct range monitors which allow the radiation therapist immediate control of the π - beam setting with respect to the tumor volume. This monitoring of range can be achieved from outside the body within short times compared to irradiation times which are typical in therapy. (orig.) [de

X-ray irradiation of yeast cells

Science.gov (United States)

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

1997-10-01

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

Yeast cell metabolism investigated by CO{_2} production and soft X-ray irradiation

Science.gov (United States)

Masini, A.; Batani, D.; Previdi, F.; Milani, M.; Pozzi, A.; Turcu, E.; Huntington, S.; Takeyasu, H.

1999-01-01

Results obtained using a new technique for studying cell metabolism are presented. The technique, consisting in CO2 production monitoring, has been applied to Saccharomyces cerevisiae yeast cells. Also the cells were irradiated using the soft X-ray laser-plasma source at Rutherford Appleton Laboratory with the aim of producing a damage of metabolic processes at the wall level, responsible for fermentation, without great interference with respiration, taking place in mitochondria, and DNA activity. The source was calibrated with PIN diodes and X-ray spectrometers and used Teflon stripes as target, emitting X-rays at about 0.9 keV, with a very low penetration in biological material. X-ray doses delivered to the different cell compartments were calculated following a Lambert-Bouguet-Beer law. Immediately after irradiation, the damage to metabolic activity was measured again by monitoring CO2 production. Results showed a general reduction in gas production by irradiated samples, together with non-linear and non-monotone response to dose. There was also evidence of oscillations in cell metabolic activity and of X-ray induced changes in oscillation frequency.

Tube closure device, especially for sample irradiation

International Nuclear Information System (INIS)

Klahn, F.C.; Nolan, J.H.; Wills, C.

1979-01-01

Device for closing the outlet of a bore and temporarily locking components in this bore. Specifically, it concerns a device for closing a tube containing a set of samples for monitoring irradiation in a nuclear reactor [fr

Review of recent studies on neutron irradiation embrittlement in light water reactor pressure vessel steels

International Nuclear Information System (INIS)

Sudo, Akira; Miyazono, Shohachiro

1983-06-01

Recent studies in foreign countries (USA, France, FRG and UK) on neutron irradiation embrittlement have been reviewed. These studies are classified into four areas, such as 1) effect of chemical composition on irradiation embrittlement sensitivity, 2) postirradiation heat treatment for embrittlement relief, 3) fracture toughness evaluation of irradiated materials based on fracture mechanics analysis, and 4) effect of irradiation on fatigue crack propagation behavior. The first area mainly includes the studies related to the effects of copper, phosphorus impurities and nickel alloying and synergistic effect of these components, and furthermore, evaluation of Regulatory Guide 1.99 Rev.l. Studies in the second area show the effects of annealing condition (temperature and time) and metallugical condition on embrittlement relief, and evaluation of periodic annealing in the period of irradiation as a promising method for embrittlement control. Studies in the third area show the correlation between fracture toughness and Cv notch ductility changes with neutron irradiation, and J-R curves of irradiated materials based on the elasto-plastic fracture mechanics. In the forth area, most of studies are investigated in air condition but a few studies in reactor-grade water at high temperature and pressure. (author)

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

Spectroscopic studies of irradiated glasses: Application in nuclear dosimetry

International Nuclear Information System (INIS)

Farah, Khaled

2010-01-01

The present work aims to study the effects of ionizing radiation on silicate glasses in order to develop a new dosimetry system simple, precise, stable and inexpensive. Indeed, changes in mechanical properties, optical and paramagnetic glasses when subjected to ionizing radiation. The prediction of long-term behavior, physical aging under irradiation, the glass is paramount. many studies have brought many ways to avoid obscuring glass windows used in nuclear reactors or hot cells and optical devices. Recently, much work has concentrated on the application of the color induced by irradiation for developing a recyclable glass in the glass industry is of great interest economically and environmentally.

Development of a Novel Preclinical Pancreatic Cancer Research Model: Bioluminescence Image-Guided Focal Irradiation and Tumor Monitoring of Orthotopic Xenografts1

Science.gov (United States)

Tuli, Richard; Surmak, Andrew; Reyes, Juvenal; Hacker-Prietz, Amy; Armour, Michael; Leubner, Ashley; Blackford, Amanda; Tryggestad, Erik; Jaffee, Elizabeth M; Wong, John; DeWeese, Theodore L; Herman, Joseph M

2012-01-01

PURPOSE: We report on a novel preclinical pancreatic cancer research model that uses bioluminescence imaging (BLI)-guided irradiation of orthotopic xenograft tumors, sparing of surrounding normal tissues, and quantitative, noninvasive longitudinal assessment of treatment response. MATERIALS AND METHODS: Luciferase-expressing MiaPaCa-2 pancreatic carcinoma cells were orthotopically injected in nude mice. BLI was compared to pathologic tumor volume, and photon emission was assessed over time. BLI was correlated to positron emission tomography (PET)/computed tomography (CT) to estimate tumor dimensions. BLI and cone-beam CT (CBCT) were used to compare tumor centroid location and estimate setup error. BLI and CBCT fusion was performed to guide irradiation of tumors using the small animal radiation research platform (SARRP). DNA damage was assessed by γ-H2Ax staining. BLI was used to longitudinally monitor treatment response. RESULTS: Bioluminescence predicted tumor volume (R = 0.8984) and increased linearly as a function of time up to a 10-fold increase in tumor burden. BLI correlated with PET/CT and necropsy specimen in size (P < .05). Two-dimensional BLI centroid accuracy was 3.5 mm relative to CBCT. BLI-guided irradiated pancreatic tumors stained positively for γ-H2Ax, whereas surrounding normal tissues were spared. Longitudinal assessment of irradiated tumors with BLI revealed significant tumor growth delay of 20 days relative to controls. CONCLUSIONS: We have successfully applied the SARRP to a bioluminescent, orthotopic preclinical pancreas cancer model to noninvasively: 1) allow the identification of tumor burden before therapy, 2) facilitate image-guided focal radiation therapy, and 3) allow normalization of tumor burden and longitudinal assessment of treatment response. PMID:22496923

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.)

Gemstone color enhancement by electron beam irradiation-A preliminary study

International Nuclear Information System (INIS)

Sarada Idris; Zulkafli Ghazali; Shamshad Ahmad; Mohd Suhaimi Jusoh

2010-01-01

Treatment of gemstones has been going on for hundreds of years for enhancing color and clarity of gems devoid of these attributes. Whereas previous practices included fraudulent or otherwise processes to achieve the color enhancement, the ionizing radiation has proven to be a reliable and reproducible technique. Three types of irradiation processes include exposure to gamma radiation, electron beam irradiation and the nuclear power plants. Electron Beam Irradiation of Gemstone is a technique in which a gemstone is exposed to highly ionizing radiation electron beam to knock off electrons to generate color centers culminating in introduction of deeper colors. The color centers may be stable or unstable. Below 9 MeV, normally no radioactivity is introduced in the exposed gems. A study was conducted at Electron Beam Irradiation Centre (Alurtron) for gemstone color enhancement by using different kind of precious gemstones mined in Pakistan and elsewhere. The study shows that EB Irradiation not only enhances the color but also improves the clarity of the gemstones. The treated stones included kunzite tourmaline topaz quartz aquamarine and cultured pearls. Doses ranging from 25 kGy to 200 kGy were employed to assess the influence of doses on color and clarity and to select the optimum doses. The samples used included both the rough and the faceted gems. It is concluded that significant revenue generation is associated with the enhancement of the color in clarity of gemstones which are available at very cheap price in the world market. (author)

In vivo genetic toxicity studies in Chinese hamsters fed irradiated or unirradiated foodstuffs

International Nuclear Information System (INIS)

Altmann, H.

1982-01-01

Two in vivo genetic toxicity studies were performed in Chinese hamsters fed irradiated or unirradiated diets of chicken, fish or dates in order to detect possible mutagenic effects caused by irradiating these foodstuffs. The tests selected for study were: 1. Chromosomal analysis of bone narrow cells and 2. DNA metabolism in spleen cells. Chicken, fish and dates were irradiated with doses of 7, 2.5 and 1 kGy respectively. These investigations were subsequently extended to include the effects of irradiated dried onions, pulses and cocoa beans on DNA metabolism in Chinese hamster spleen cells only. Dried onions were irradiated with doses of 0.15, 9 and 15 kGy, pulses with 10 kGy and cocoa beans with 3.2 to 5 kGy. In addition, a fumigated cocoa bean group was included. No significant differences in chromosomal aberration rate were detected between groups fed irradiated or unirradiated diets. Dried dates, whether irradiated or not, showed some evidence of genetic toxicity in their effect on DNA metabolism in the spleen cells of Chinese hamsters. Both date diets caused more strand breaks DNA than are usual for Chinese hamster spleen cells, but DNA repair was not adversely affected. Chicken, both irradiated and unirradiated, was found to enhance replicative DNA synthesis but had no effect on the DNA repair process. Irradiated fish, however, caused enhanced DNA synthesis compared to unirradiated fish, but also had no adverse effect on DNA repair. Irradiated white beans also enhanced DNA synthesis compared to controls whereas unirradiated samples inhibited synthesis. (orig./MG)

A study of the physiological changes and the nutritional qualities of irradiated apples and the effect of irradiation on apples stored at room temperature

International Nuclear Information System (INIS)

Wang Chuanyao; Jiang Mengyue; Gao Meixu; Ma Xiuye; Zhang Shufen; Liu Shucheng

1993-01-01

The effects of γ-irradiation on the metabolism and nutritional qualities of Golden Delicious apples and on the lethality of pathogenic fungi have been studied. The storage effect of irradiation on apples at room temperature has been observed. Results showed that the respiratory intensity of irradiated apple at 0.3-0.5 kGy was near or lower than that of unirradiated apple after 15 days irradiation. The amount of ethylene release was obviously inhibited when fruits were irradiated with 0.3-0.7 kGy. The flesh firmness of apples irradiated with 0.3-0.9 kGy was higher than that of unirradiated apple with increased storage time. The negative correlations between the flesh firmness and the activities of pectinesterase (PE), polygalacturonase (PG) were observed when the dosage was lower than 1.5 kGy. The 2.0 kGy irradiation damaged the ultrastructure of cells, induced the softening of apple. When apples were irradiated with 0.7-2.0 kGy, the contents of 4 important volatile components of apple would be decreased. However, this dose had no effects on the pure chemicals. Studies showed that there was no significant effect of irradiation with 0.3-2.0 kGy on the nutritional qualities of apples and this dose range could effectively control the verticillate pathogenic fungi. The result of storage experiment showed that rotting of fruits decreased by 0.3-0.9 kGy irradiation. (author)

On the ultrasonic irradiation in the photosynthetic activity of aquatic lirium (Eichornia crassipes)

Energy Technology Data Exchange (ETDEWEB)

Calderon, A.; Cardona, A.; Juarez G, A. G.; Marin, E.; Munoz H, R. A.; Diaz G, J. A., E-mail: jcalderona@ipn.mx [IPN, Centro de Investigacion en Ciencia Aplicada y Tecnologia Avanzada, Calz. Legaria No. 694, Col. Irrigacion, 11500 Mexico D. F. (Mexico)

2012-10-15

We report, for the first time, the application of the photoacoustic technique for monitoring the photosynthesis evolution in aquatic lirium (Eichornia crassipes), before and after it was exposed to ultrasonic irradiations. We obtained the disappearance of the phototobaric contribution in the Pa signal measured for the irradiated samples with ultrasound of 17 khz, and therefore of a possible damage in the centers producing the photosynthesis, due to the irradiation. These results show the utility of the ultrasonic irradiation, as well as, of the photosynthesis monitoring by means of the photoacoustic technique, for the elaboration and establishment of methodologies in the control of this aquatic plant, whose propagation causes many consequences extremely unfavorable for the environment, as well as for the diverse human activities that are developed in the bodies of water in the tropical and sub-tropical regions of the world. (Author)

On the ultrasonic irradiation in the photosynthetic activity of aquatic lirium (Eichornia crassipes)

International Nuclear Information System (INIS)

Calderon, A.; Cardona, A.; Juarez G, A. G.; Marin, E.; Munoz H, R. A.; Diaz G, J. A.

2012-10-01

We report, for the first time, the application of the photoacoustic technique for monitoring the photosynthesis evolution in aquatic lirium (Eichornia crassipes), before and after it was exposed to ultrasonic irradiations. We obtained the disappearance of the phototobaric contribution in the Pa signal measured for the irradiated samples with ultrasound of 17 khz, and therefore of a possible damage in the centers producing the photosynthesis, due to the irradiation. These results show the utility of the ultrasonic irradiation, as well as, of the photosynthesis monitoring by means of the photoacoustic technique, for the elaboration and establishment of methodologies in the control of this aquatic plant, whose propagation causes many consequences extremely unfavorable for the environment, as well as for the diverse human activities that are developed in the bodies of water in the tropical and sub-tropical regions of the world. (Author)

Verification of neutron irradiation on S/G tube materials

International Nuclear Information System (INIS)

Kang, Byoung Hwi; Lee, S. K.; Jang, D. Y.; Jo, K. H.

2010-12-01

The fluence monitors were fabricated with metal wires of the purity ≥ 99.9%, whose dimensions were 0.1mm diameter, about 3mm length, and around 150-200 μg mass range. Three wire samples (Fe, Ni, Ti) were prepared for one irradiation aluminum capsule. Five capsules were irradiated in the OR5 hole of the HANARO reactor at 30 MW power for about 25 days. The reaction rates were calculated by using the measured radiation activity data, and then neutron fluence were obtained from the reaction rates and the weighted neutron cross section with calculated neutron spectrum at the fluence monitor position. The measured neutron fluences were compared to the calculated ones. (Errors ≤ 35%)

Monitoring for fuel sheath defects in three shipments of irradiated CANDU nuclear fuel

International Nuclear Information System (INIS)

Johnson, H.M.

1978-01-01

Analyses of radioactive gases within the Pegase shipping flask were performed at the outset and at the completion of three shipments of irradiated nuclear fuel from the Douglas Point Generating Station to Whiteshell Nuclear Research Establishment. No increases in the concentration of active gases, volatiles or particulates were observed. The activity of the WR-1 bay water rose only marginally due to the storage of the fuel. Other tests indicated that minimal surface contamination was present. These data established that defects in fuel element sheaths did not arise during the transport or the handling of this irradiated fuel. The observation has significance for the prospect of irradiated nuclear fuel transfer and handling in preparation for storage or disposal. (author)

A comparative study of standard intensity-modulated radiotherapy and RapidArc planning techniques for ipsilateral and bilateral head and neck irradiation

Energy Technology Data Exchange (ETDEWEB)

Pursley, Jennifer, E-mail: jpursley@mgh.harvard.edu [Department of Radiation Oncology, Dana-Farber Cancer Institute/Brigham and Women' s Hospital, Boston, MA (United States); Department of Radiation Oncology, Massachusetts General Hospital, Boston, MA (United States); Damato, Antonio L.; Czerminska, Maria A.; Margalit, Danielle N. [Department of Radiation Oncology, Dana-Farber Cancer Institute/Brigham and Women' s Hospital, Boston, MA (United States); Sher, David J. [Department of Radiation Oncology, Dana-Farber Cancer Institute/Brigham and Women' s Hospital, Boston, MA (United States); Department of Radiation Oncology, UT Southwestern Medical Center, Dallas, TX (United States); Tishler, Roy B. [Department of Radiation Oncology, Dana-Farber Cancer Institute/Brigham and Women' s Hospital, Boston, MA (United States)

2017-04-01

The purpose of this study was to investigate class solutions using RapidArc volumetric-modulated arc therapy (VMAT) planning for ipsilateral and bilateral head and neck (H&N) irradiation, and to compare dosimetric results with intensity-modulated radiotherapy (IMRT) plans. A total of 14 patients who received ipsilateral and 10 patients who received bilateral head and neck irradiation were retrospectively replanned with several volumetric-modulated arc therapy techniques. For ipsilateral neck irradiation, the volumetric-modulated arc therapy techniques included two 360° arcs, two 360° arcs with avoidance sectors around the contralateral parotid, two 260° or 270° arcs, and two 210° arcs. For bilateral neck irradiation, the volumetric-modulated arc therapy techniques included two 360° arcs, two 360° arcs with avoidance sectors around the shoulders, and 3 arcs. All patients had a sliding-window-delivery intensity-modulated radiotherapy plan that was used as the benchmark for dosimetric comparison. For ipsilateral neck irradiation, a volumetric-modulated arc therapy technique using two 360° arcs with avoidance sectors around the contralateral parotid was dosimetrically comparable to intensity-modulated radiotherapy, with improved conformity (conformity index = 1.22 vs 1.36, p < 0.04) and lower contralateral parotid mean dose (5.6 vs 6.8 Gy, p < 0.03). For bilateral neck irradiation, 3-arc volumetric-modulated arc therapy techniques were dosimetrically comparable to intensity-modulated radiotherapy while also avoiding irradiation through the shoulders. All volumetric-modulated arc therapy techniques required fewer monitor units than sliding-window intensity-modulated radiotherapy to deliver treatment, with an average reduction of 35% for ipsilateral plans and 67% for bilateral plans. Thus, for ipsilateral head and neck irradiation a volumetric-modulated arc therapy technique using two 360° arcs with avoidance sectors around the contralateral parotid is

Systematic Study of the PbWO4 Crystal Short Term Instalibity Under Irradiation

CERN Document Server

Annenkov, Alexander; Chipaux, Rémi; Drobychev, Gleb; Fedorov, Andrey; Géléoc, Marie; Golubev, Nikolai; Korzhik, Mikhail; Lecoq, Paul; Ligun, A B; Missevitch, Oleg; Pavlenko, V B; Peigneux, Jean-Pierre; Singovsky, Alexander

1997-01-01

The effect of the irradiation on the lead tungstate ( PWO) scintillator properties has been studied at different irradiation facilities. Lead tungstate crystals grown with the tuning of oxides content in the melt to the stoichiometry of pure sheelite or sheelite-like type crystals and doped with heterovalent, trivalent and pentavalent impurities have been studied in order to optimize their resistance to irradiation. A combination of a selective cleaning of raw materials, a tuning of the melt from crystallization to crystallisation, and a destruction or compensation of the point structure defects has been used to minimize the short-term instability of PWO parameters under irradiation.

Irradiation-induced precipitates in a neutron irradiated 304 stainless steel studied by three-dimensional atom probe

Energy Technology Data Exchange (ETDEWEB)

Toyama, T., E-mail: ttoyama@imr.tohoku.ac.jp [International Research Center for Nuclear Materials Science, Institute for Materials Research, Tohoku University, Narita-cho 2145-2, Oarai, Ibaraki 311-1313 (Japan); Nozawa, Y. [International Research Center for Nuclear Materials Science, Institute for Materials Research, Tohoku University, Narita-cho 2145-2, Oarai, Ibaraki 311-1313 (Japan); Van Renterghem, W. [SCK-CEN, Nuclear Materials Science Institute, Boeretang 200, 2400 Mol (Belgium); Matsukawa, Y.; Hatakeyama, M.; Nagai, Y. [International Research Center for Nuclear Materials Science, Institute for Materials Research, Tohoku University, Narita-cho 2145-2, Oarai, Ibaraki 311-1313 (Japan); Al Mazouzi, A. [EDF R and D, Avenue des Renardieres Ecuelles, 77818 Moret sur Loing Cedex (France); Van Dyck, S. [SCK-CEN, Nuclear Materials Science Institute, Boeretang 200, 2400 Mol (Belgium)

2011-11-15

Highlights: > Irradiation-induced precipitates in a 304 stainless steel were investigated by three-dimensional atom probe. > The precipitates were found to be {gamma}' precipitates (Ni{sub 3}Si). > Post-irradiation annealing was performed to discuss the contribution of the precipitates to irradiation-hardening. - Abstract: Irradiation-induced precipitates in a 304 stainless steel, neutron-irradiated to a dose of 24 dpa at 300 deg. C in the fuel wrapper plates of a commercial pressurized water reactor, were investigated by laser-assisted three-dimensional atom probe. A high number density of 4 x 10{sup 23} m{sup -3} of Ni-Si rich precipitates was observed, which is one order of magnitude higher than that of Frank loops. The average diameter was {approx}10 nm and the average chemical composition was 40% Ni, 14% Si, 11% Cr and 32% Fe in atomic percent. Over a range of Si concentrations, the ratio of Ni to Si was {approx}3, close to that of {gamma}' precipitate (Ni{sub 3}Si). In some precipitates, Mn enrichment inside the precipitate and P segregation at the interface were observed. Post-irradiation annealing was performed to discuss the contribution of the precipitates to irradiation-hardening.

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.)

Studies of Sterile Irradiation Effects on the White-striped Fruit Fly

International Nuclear Information System (INIS)

Limohpasmanee, Wanitch; Tannarin, Thodsapol; Khongratarpon, Titima; Segsarnviriya, Suchada

2011-06-01

Full text: In general, sterile irradiation can affect vigor and mating competitiveness of the fruit flies. The objective of the experiments was to study the effects of sterile irradiation on the white-striped oriental fruit fly, Bactrocera dorsalis (Hendel), developed for sterile fly detection. A day before adult emergence, the pupae were irradiated at the dose of 90 Grays. No effects on adult emergence and flight ability were observed. However, it induced complete sterility in both sexes. Also, it decreased male mating competitiveness significantly, while increasing sexual competitiveness significantly

Study of damages by neutron irradiation in lithium aluminates

International Nuclear Information System (INIS)

Palacios G, O.

1999-01-01

Lithium aluminates proposed to the production of tritium in fusion nuclear reactors, due to the thermal stability that they present as well as the behavior of the aluminium to the irradiation. As a neutron flux with profile (≅ 14 Mev) of a fusion reactor is not available. A irradiation experiment was designed in order to know the micro and nano structure damages produced by fast and thermal neutrons in two irradiation positions of the fusion nuclear reactor Triga Mark III: CT (Thermal Column) and SIFCA (System of Irradiation Fixed of Capsules). In this work samples of lithium aluminate were characterized by XRD (X-Ray Diffraction), TEM (Transmission Electron Microscopy) and SEM (Scanning Electron Microscopy). Two samples were prepared by two methods: a) coalition method and b) peroxide method. This characterization comprised original and irradiated samples. The irradiated sample amounted to 4 in total: one for each preparation method and one for each irradiation position. The object of this analysis was to correlate with the received neutron dose the damages suffered by the samples with the neutron irradiation during long periods (440 H), in their micro and nano structure aspects; in order to understand the changes as a function of the irradiation zone (with thermal and fast neutron flux) and the preparation methods of the samples and having as an antecedent the irradiation in SIFCA position by short times (2h). The obtained results are referred to the stability of γ -aluminate phase, under given conditions of irradiation and defined nano structure arrangement. They also refer to the proposals of growth mechanism and nucleation of new phases. The error associated with the measurement of neutron dose is also discussed. (Author)

Monitoring of releases from an irradiated fuel reprocessing plant

International Nuclear Information System (INIS)

Fitoussi, L.

1978-01-01

At its UP 2 plant, the La Hague facility reprocesses irradiated fuel by the PUREX process. The fuel stems from graphite/gas, natural-uranium reactors and pressurized or boiling water enriched-uranium reactors. The gaseous effluents are collected and purified by high-efficiency washing and filtration. After purification the gas stream is discharged into the atmosphere by a single stack, 100m high and 6m in diameter, located at a high point on the site (184m). The radionuclides released into the air are: krypton-85, iodine-129 and -131, and tritium. The liquid effluents are collected by drainage systems, which transfer them to the effluent treatment station in the case of active or suspect solutions. Active solutions undergo treatment by chemical and physical processes. After purification the waste water is released into the sea by an underwater drainage system 5km long, which brings the outlet point into the middle of a tidal current 2km offshore. The radionuclides contained in the purified waste water are fission products originating from irradiated fuels in only slightly variable proportions, in which ruthenium-rhodium-106 predominates. Traces of the transuranium elements are also found in these solutions

Genetic monitoring of irradiated Drosophila populations treated with antimutagen melanine

International Nuclear Information System (INIS)

Mosseh, I.B.; Savchenko, V.K.; Lyakh, I.P.

1986-01-01

It was shown that viability of irradiated Drosophila is, on an average, lower than in intact populations. The fertility first decreases then increases exceeding the control level. Melanine added to the diet increases fertility and viability of both exposed and intact Drosophila populations

Personnel monitoring in geologic fields

International Nuclear Information System (INIS)

Romanova, I.N.; Seredin, Yu.V.

1981-01-01

State of radiation safety for the personnel of geologic crews carrying out neutron logging of wells using Po-Be sources has been evaluated. Given are results of development of methods for the evaluation of individual radiation loads for personnel when working with Po-Be neutron sources useful for the application in practice by a geologic logging crew as well as a quantitative evaluation of profissional radiation loads during this kind of work. The following methods are recommended for personnel monitoring: 1) calculation of whole-body irradiation doses and hands from averaged values of radiation dose rate; 2) calculational tabulated determination of irradiation doses during recharging of shanks of well instruments. Personnel monitoring by means of instrumental methods is not necessary in the considered case [ru

Experimental studies on the effect of perfluorochemicals in tumor irradiation

International Nuclear Information System (INIS)

Shinoda, Jun; Iwai, Tomohiko; Hattori, Tatsuaki; Kondo, Hiroaki; Sakai, Noboru; Yamada, Hiroshi

1984-01-01

The effects of radiation therapy with Fluosol-DA on rat mammary tumors were studied. The tissue oxygen tension values of tumors in breathing mixed gas (5% carbon dioxide and 95% oxygen) with Fluosol-DA (25 ml/kg, i.v.) were significantly higher than those in room air without Fluosol-DA. The rats were divided into three groups: Group I received Fluosol-DA but no irradiation, Group II was treated with 1000 rads of irradiation using 60 Co without Fluosol-DA in room air and Group III received the same irradiation and Fluosol-DA in breathig mixed gas. In the latter group we observed a prolongation of the survival time and suppression of the tumor growth. (author)

Toxicological studies on irradiated food and food constituents

International Nuclear Information System (INIS)

Schubert, J.

1978-01-01

Selected aspects of the genotoxicology and chemistry of irradiated foods and food components are critically examined and compared with other food processing operations such as cooking, and intentional use of food additives. For example, it is estimated that if 10% of an average daily diet contained irradiated (<1.0Mrad) foods, the daily consumption of radiolytic products would be 2-20mg/d compared with a total of approximately 4000mg/d of intentional food additives and approximately 80mg/d of toxic inorganic and organic environmentally derived contaminants. Several recommendations for the genotoxicological testing of irradiated foods are given, including: (1) that feeding tests include a control diet consisting of food processed by one of the standard methods such as thermalization; (2) that more use be made of positive controls so as to have a 'built-in' measure of sensitivity and responsiveness; (3) that a battery of in vitro and in vivo short-term mutagenicity tests be performed prior to the carrying out of the long-term feeding tests; and (4) that an irradiated food be tested after it is cooked in the manner normally consumed, which may, of course, include the raw or uncooked state as well. An outline of current genetic-toxicological testing schemes is provided and examined. Emphasis is given to a modification in the protocols for the Ames mutagenicity tests leading to a reduction in the evidence of false positives and false negatives. Also described is a procedure for systematically studying combined or interactive effects, acute or chronic, which requires no more effort than that needed for testing a single agent and which yields complete dose-response curves. It is concluded that food irradiation, as a physical process, appears more advantageous from the genotoxicological, chemical, and pollution aspects than well-accepted, but actually rarely tested, physical processes such as canning. (author)

Self-shielding and burn-out effects in the irradiation of strongly-neutron-absorbing material

International Nuclear Information System (INIS)

Sekine, T.; Baba, H.

1978-01-01

Self-shielding and burn-out effects are discussed in the evaluation of radioisotopes formed by neutron irradiation of a strongly-neutron-absorbing material. A method of the evaluation of such effects is developed both for thermal and epithermal neutrons. Gadolinium oxide uniformly mixed with graphite powder was irradiated by reactor-neutrons together with pieces of a Co-Al alloy wire (the content of Co being 0.475%) as the neutron flux monitor. The configuration of the samples and flux monitors in each of two irradiations is illustrated. The yields of activities produced in the irradiated samples were determined by the γ-spectrometry with a Ge(Li) detector of a relative detection efficiency of 8%. Activities at the end of irradiation were estimated by corrections due to pile-up, self-absorption, detection efficiency, branching ratio, and decay of the activity. Results of the calculation are discussed in comparison with the observed yields of 153 Gd, 160 Tb, and 161 Tb for the case of neutron irradiation of disc-shaped targets of gadolinium oxide. (T.G.)

Electron microscopic study of the spilt irradiation effects on the rat parotid ductal cells

International Nuclear Information System (INIS)

Kim, Sung Soo; Lee, Sang Rae

1988-01-01

This study was designed to investigate the effects of split irradiation on the salivary ductal cells, especially on the intercalated cells of the rat parotid glands. For this study, 24 Sprague-Dawley strain rats were irradiated on the head and neck region with two equal split doses of 9 Gy for a 4 hours interval by Co-60 teletherapy unit, Picker's mode l 4M 60. The conditions of irradiation were that field size, dose rate, SSD and depth were 12 X 5 cm, 222 cGy/min, 50 cm and 1 cm, respectively. The experimental animals were sacrificed 1, 2, 3, 6, 12, hours and 1, 3, 7, days after the irradiation and the changes of the irradiated intercalated cells of the parotid glands were examined under light and electron microscope. The results were as follows: 1. By the split irradiation, the degenerative changes of intercalated cells of the parotid glands appeared at 3 hours after irradiation and the most severe cellular degeneration observed at 6 hours after irradiation. The repair processes began from 12 hours after irradiation and have matured progressively. 2. Under electron microscope, loss of nuclear membrane, microvilli and secretory granules, derangement of chromosomes, degeneration of cytoplasm, atrophy or reduction of intracytoplasmic organelles were observed in the intercalated ductal cells after split irradiation. 3. Under light microscope, derangement of ductal cells, widening of cytoplasms and nuclei, hyperchromatism and proliferation of ductal cells were observed in intercalated ducts after split irradiation.

Studies on the preservation of Korean Ginseng by irradiation

International Nuclear Information System (INIS)

Sung, H.S.; Park, M.H.; Lee, K.S.; Cho, H.O.

1982-01-01

In order to evaluate the feasibility for the sterilization of Korean red and white ginseng powder by irradiation, red and white ginseng powder (120 mesh) was irradiated by 0.1, 0.3, 0.5, 0.7, 1.0 and 2.0 Mrad with 60 Co irradiator (dose rate: 4000 rad/h). Extraction rate of crude saponins by buthanol and by 50% ethanol were slightly increased according to the irradiation dose (buthanol ex. 1.7%, 50% ethanol ex. 2.6%) at 1.0 Mrad irradiation. There are no remarkable changes in HPLC patterns of crude saponins by radiation. It was found that irradiation up to 1 Mrad on Korean ginseng products have no significant effect on proximate component, reducing sugar and amino nitrogen of ginseng powder and on the color density of ginseng extract with 50% ethanol. Irradiation up to 1 Mrad could be utilized for the sterilization of Korean ginseng powder without changes of physicochemical properties. (Author)

Positron annihilation study of defects in electron-irradiated single crystal zinc oxide

Science.gov (United States)

To, C. K.; Yang, B.; Beling, C. D.; Fung, S.; Ling, C. C.; Gong, M.

2011-01-01

Pressurized melt grown zinc oxide (ZnO) single crystals purchased from Cermet Inc. were irradiated by 2MeV electrons with fluence of 6x1017cm-2. Isochronal annealing from 100°C-800°C was performed on the crystals under argon and air ambience. Variable Energy Doppler Broadening Spectroscopy (VEDBS) was carried out on both the as-grown and the irradiated samples at each annealing step. The migration, agglomeration and annealing of grown-in and irradiated-introduced defects were studied. It was observed that the grown-in vacancy-type defects concentration decreased at 300°C and 600 °C. For the irradiated sample annealed in argon, the positron trapping vacancy-type defect concentration decreased at 300°C and 600°C. Further annealing the as-grown and irradiated samples in argon increased the S parameter further. For the irradiated sample annealed in air, the vacancy-type defect concentration decreases at 300°C and 700°C.

Positron annihilation study of defects in electron-irradiated single crystal zinc oxide

Energy Technology Data Exchange (ETDEWEB)

To, C K; Yang, B; Beling, C D; Fung, S; Ling, C C [Department of Physics, University of Hong Kong (Hong Kong); Gong, M, E-mail: sfung@hkucc.hku.h, E-mail: edwardto04@yahoo.com.h [Department of Physics, Sichuan University, Chengdu (China)

2011-01-01

Pressurized melt grown zinc oxide (ZnO) single crystals purchased from Cermet Inc. were irradiated by 2 MeV electrons with fluence of 6x10{sup 17}cm{sup -2}. Isochronal annealing from 100 deg. C - 800 deg. C was performed on the crystals under argon and air ambience. Variable Energy Doppler Broadening Spectroscopy (VEDBS) was carried out on both the as-grown and the irradiated samples at each annealing step. The migration, agglomeration and annealing of grown-in and irradiated-introduced defects were studied. It was observed that the grown-in vacancy-type defects concentration decreased at 300 deg. C and 600 deg. C. For the irradiated sample annealed in argon, the positron trapping vacancy-type defect concentration decreased at 300 deg. C and 600 deg. C. Further annealing the as-grown and irradiated samples in argon increased the S parameter further. For the irradiated sample annealed in air, the vacancy-type defect concentration decreases at 300 deg. C and 700 deg. C.

Positron annihilation study of defects in electron-irradiated single crystal zinc oxide

International Nuclear Information System (INIS)

To, C K; Yang, B; Beling, C D; Fung, S; Ling, C C; Gong, M

2011-01-01

Pressurized melt grown zinc oxide (ZnO) single crystals purchased from Cermet Inc. were irradiated by 2 MeV electrons with fluence of 6x10 17 cm -2 . Isochronal annealing from 100 deg. C - 800 deg. C was performed on the crystals under argon and air ambience. Variable Energy Doppler Broadening Spectroscopy (VEDBS) was carried out on both the as-grown and the irradiated samples at each annealing step. The migration, agglomeration and annealing of grown-in and irradiated-introduced defects were studied. It was observed that the grown-in vacancy-type defects concentration decreased at 300 deg. C and 600 deg. C. For the irradiated sample annealed in argon, the positron trapping vacancy-type defect concentration decreased at 300 deg. C and 600 deg. C. Further annealing the as-grown and irradiated samples in argon increased the S parameter further. For the irradiated sample annealed in air, the vacancy-type defect concentration decreases at 300 deg. C and 700 deg. C.

Study of the irradiation defects in 3C-SiC

International Nuclear Information System (INIS)

Lefevre, J.

2007-01-01

This work deals with the study of the irradiation defects in the cubic polytype 3C of the n type silicon carbide. Low temperature photoluminescence and electron spin resonance techniques have been used. In situ photoluminescence measurements after irradiation at 10 K by electrons have shown that the nature of the defects induced is identical to those observed after irradiation at ambient temperature with electrons, protons or carbon ions. No regeneration of these defects has been revealed after in situ annealings until 300 K. The electrons Van de Graff accelerator of the Irradiated Solid Laboratory has allowed to irradiate sample of 3C in a range of energies between 190 keV and 1 MeV. It has then been possible to estimate the appearance threshold of the irradiation defects but especially to be able to determine the displacement threshold energy of silicon in this SiC polytype. The found value of 25 eV is in good agreement with the first experimental result proposed by X. Kerbiriou with the use of the ESR. Annealings in the range of high temperatures have been carried out. The evolution of the irradiation defects has been followed in photoluminescence and in ESR. The results show that, in one part, the vacancy of the silicon negatively charged is essentially the only compensating defect in 3C-SiC of n type and that, in another part, the majority of the defects are annealed below 1200 C. Only the D1 defect remains after annealings until 1600 C. The D1 center is in fact a native defect in SiC; indeed, it has been identified alone in non irradiated samples. A systematic study of these last samples show the absence of D1 in samples strongly compensated. The compared results of photoluminescence and of positons annihilation are in good agreement for the possible attribution of D1 to the bi-vacancy V C -V Si . One of the most interesting result of this last work has been obtained using the ESR technique under excitation with a neodymium laser. The measurements, carried

Effect of γ-irradiation on the volatile compounds of medicinal herb, Paeoniae Radix

International Nuclear Information System (INIS)

Shim, Sung-Lye; Hwang, In-Min; Ryu, Keun-Young; Jung, Min-Seok; Seo, Hye-young; Kim, Hee-Yeon; Song, Hyun-Pa; Kim, Jae-Hun; Lee, Ju-Woon; Byun, Myung-Woo; Kwon, Joong-Ho; Kim, Kyong-Su

2009-01-01

A study was carried out to find the effect of γ-irradiation on contents of volatile compounds from medicinal herb, Paeoniae Radix (Paenia albiflora Pallas var. trichocarpa Bunge). The volatile compounds of control, 1, 3, 5 and 10 kGy irradiated samples were extracted by simultaneous steam distillation and extraction (SDE) method and analyzed by gas chromatograph-mass spectrometer. The major volatile compounds were paeonol, (E)-carveol, (E,E)-2,4-octadienal, methyl salicylate, myrtanol and eugenol acetate. Volatile compounds belonging to chemical classes of acids, alcohols, aldehydes, esters, hydrocarbons and miscellaneous were identified in all experimental samples. The types of volatile compounds in irradiated samples were similar to those of non-irradiated sample and the concentrations of these compounds differed between treatments. 1,3-Bis (1,1-dimethylethyl)-benzene was identified by using the selected ion monitoring (GC/MS-SIM) mode. The concentration of this compound increased with the increase of irradiation dose level. These results suggest that it could be used as the base data for the effect of γ-irradiation on medicinal herb.

Effect of {gamma}-irradiation on the volatile compounds of medicinal herb, Paeoniae Radix

Energy Technology Data Exchange (ETDEWEB)

Shim, Sung-Lye; Hwang, In-Min; Ryu, Keun-Young; Jung, Min-Seok [Department of Food and Nutrition, Chosun University (Korea, Republic of); Seo, Hye-young [Korea Food Research Institute (Korea, Republic of); Kim, Hee-Yeon [Korea Food and Drug Administration (Korea, Republic of); Song, Hyun-Pa; Kim, Jae-Hun; Lee, Ju-Woon; Byun, Myung-Woo [Advanced Radiation Technology Institute, KAERI, Jeongeup 580-185 (Korea, Republic of); Kwon, Joong-Ho [Department of Food Science and Technology, Kyungpook National University (Korea, Republic of); Kim, Kyong-Su [Korea Food Research Institute (Korea, Republic of)], E-mail: kskim@chosun.ac.kr

2009-07-15

A study was carried out to find the effect of {gamma}-irradiation on contents of volatile compounds from medicinal herb, Paeoniae Radix (Paenia albiflora Pallas var. trichocarpa Bunge). The volatile compounds of control, 1, 3, 5 and 10 kGy irradiated samples were extracted by simultaneous steam distillation and extraction (SDE) method and analyzed by gas chromatograph-mass spectrometer. The major volatile compounds were paeonol, (E)-carveol, (E,E)-2,4-octadienal, methyl salicylate, myrtanol and eugenol acetate. Volatile compounds belonging to chemical classes of acids, alcohols, aldehydes, esters, hydrocarbons and miscellaneous were identified in all experimental samples. The types of volatile compounds in irradiated samples were similar to those of non-irradiated sample and the concentrations of these compounds differed between treatments. 1,3-Bis (1,1-dimethylethyl)-benzene was identified by using the selected ion monitoring (GC/MS-SIM) mode. The concentration of this compound increased with the increase of irradiation dose level. These results suggest that it could be used as the base data for the effect of {gamma}-irradiation on medicinal herb.

Study of energetic-particle-irradiation induced biological effect on Rhizopus oryzae through synchrotron-FTIR micro-spectroscopy

Science.gov (United States)

Liu, Jinghua; Qi, Zeming; Huang, Qing; Wei, Xiaoli; Ke, Zhigang; Fang, Yusheng; Tian, Yangchao; Yu, Zengliang

2013-01-01

Energetic particles exist ubiquitously and cause varied biological effects such as DNA strand breaks, lipid peroxidation, protein modification, cell apoptosis or death. An emerging biotechnology based on ion-beam technique has been developed to serve as an effective tool for mutation breeding of crops and microbes. In order to improve the effectiveness of ion-beam biotechnology for mutation breeding, it is indispensible to gain a better understanding of the mechanism of the interactions between the energetic ions and biological systems which is still elusive. A new trend is to conduct more comprehensive research which is based on micro-scaled observation of the changes of the cellular structures and compositions under the interactions. For this purpose, advanced synchrotron FTIR (s-FTIR) microscopy was employed to monitor the cellular changes of single fungal hyphae under irradiation of α-particles from 241Am. Intracellular contents of ROS, MDA, GSSG/GSH and activities of CAT and SOD were measured via biochemical assay. Ion-irradiation on Rhizopus oryzae causes localized vacuolation, autolysis of cell wall and membrane, lipid peroxidation, DNA damage and conformational changes of proteins, which have been clearly revealed by the s-FTIR microspectroscopy. The different changes of cell viability, SOD and CAT activities can be explained by the ROS-involved chemical reactions. Evidently, the elevated level of ROS in hyphal cells upon irradiation plays the key role in the caused biological effect. This study demonstrates that s-FTIR microspectroscopy is an effective tool to study the damage of fungal hyphae caused by ionizing radiation and it facilitates the exploit of the mechanism for the interactions between the energetic ions and biological systems.

Study of irradiation effects in austenitic stainless steels

Energy Technology Data Exchange (ETDEWEB)

Etienne, A. [GPM UMR CNRS 6634, Universite et INSA de Rouen (France); Material Department, University of California, Santa Barbara (United States); Pareige, P.; Radiguet, B. [GPM UMR CNRS 6634, Universite et INSA de Rouen (France); Cunningham, N.J.; Odette, G.O. [Material Department, University of California, Santa Barbara (United States); Pokor, C. [EDF RD, departement MMC, site des Renardieres, Moret-sur-Loing (France)

2011-07-01

Chemical analyses using Atom Probe Tomography were performed on a bolt made of cold worked 316 austenitic stainless steel, extracted from the internal structures of a pressurized water reactor after seventeen years of reactor service. The irradiation temperature of these samples was 633 K and the irradiation dose was estimated to 12 dpa. These analyses have shown that neutron irradiation has a strong effect on the intragranular distribution of solute atoms. A very high number density (6.10{sup 23} m{sup -3}) of Ni-Si enriched and Cr-Fe depleted clusters was detected after irradiation. In order to bring complementary experimental results and to determine the mechanism of formation of these Ni-Si nano-clusters, Fe{sup 5+} ion irradiations have been performed on a 316 austenitic stainless steel. As after neutron irradiation, the formation of solute enriched features is observed. Linear features and two kinds of clusters, rounded and torus shaped, are present. Considering that solute enriched features are probably formed by radiation induced segregation on point defect sinks, these different shapes are due to the nature of the sinks where segregation occurs. (authors)

Neutron metrology in the HFR. Steel irradiation. R139-801 (SINAS)

International Nuclear Information System (INIS)

Ketema, D.J.

1999-02-01

The R139-80 series irradiation experiments is part of the NRG materials test programme to evaluate the irradiation behaviour of several types of austenitic stainless steel. Within this programme five R139-80 specimen holders were irradiated in the HFR Petten to different dose levels. This report presents the final metrology results obtained from activation monitors in a specimen holder, coded as R139-801, containing 12 Compact Tension (CT-10 mm) specimens made from the austenitic stainless steel types 308LSXB/TIG and 304-SXB. The R139-801 assembly was irradiated in channel 1 of a TRIO type facility placed in HFR core-position F8. The aim of this irradiation of specimen holder R139-801 was to reach a minimum target damage level of 7.5 dpa for the specimens at a temperature of 335C. The monitor sets are used to calculate the thermal and fast neutron fluences, displacements per atom and the generated helium content. Additionally detailed information concerning an estimation of the fluence and damage doses received by each specimen and its temperature during irradiation are presented. The main results of the thermal and fast neutron fluence measurements are presented. The results indicate that the obtained damage levels in the steel specimens loaded in this specimen holder vary from 5.8 to 7.9 dpa. The temperatures of the specimens during irradiation varied between 304 and 337C. 14 refs

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

The effects of gamma irradiation on the fate of hindered phenol antioxidants in food contact polymers. Analytical and 14C-labelling studies

International Nuclear Information System (INIS)

Allen, D.W.; Leathard, D.A.; Smith, C.

1991-01-01

The extractable levels of two hindered phenol antioxidants (Irganox 1076 and Irganox 1010) present in PVC, polyethylene and polypropylene have been monitored by HPLC techniques following progressive exposure of the polymers to 60 Co(gamma) radiation. There is a gradual diminution in the extractable levels of each antioxidant as irradiation progresses as a result of transformation of the antioxidants in the oxidation reactions ensuing during irradiation. Experiments involving the use of a 14 C-labelled sample of Irganox 1076 in polyolefins have provided evidence of covalent binding of antioxidant degradation products to the polymer following gamma irradiation. However, there is also evidence of the formation of extractable degradation products, the identity of which is as yet unknown. (author)

The effects of gamma irradiation on the fate of hindered phenol antioxidants in food contact polymers. Analytical and 14C-labelling studies

Science.gov (United States)

Allen, David W.; Leathard, David A.; Smith, Christine

The extractable levels of two hindered phenol antioxidants (Irganox 1076 and Irganox 1010) present in PVC, polyethylene and polypropylene, have been monitored by HPLC techniques following progressive exposure of the polymers to 60Co γ radiation. There is a gradual diminution in the extractable levels of each antioxidant as irradiation progresses as a result of transformation of the antioxidants in the oxidation reactions ensuing during irradiation. Experiments involving the use of a 14C-labelled sample of Irganox 1076 in polyolefins have provided evidence of covalent binding of antioxidant degradation products to the polymer following gamma irradiation. However, there is also evidence of the formation of extractable degradation products, the identity of which is as yet unknown.

Morphological studies on the healing process of extraction wound in irradiated rats

International Nuclear Information System (INIS)

Iizuka, Tadashi

1984-01-01

The present studies were performed to investigate the healing process of the extraction wound in irradiated rats and to clarify the effect of irradiation on bone formation and resorption. 282 Wistar rats of about 100g body weight were used. The region of the left upper molars of experimental rats was exposed to 1000 rad or 2000 rad of 60 Co. On the 7th day after irradiation, the left upper first molar of each rat was extracted. The rats were sacrificed at intervals of from 1 day to 28 days after extraction. Control rats were sacrificed at same intervals after extraction. The maxillary bone including the extraction wound was examined histologically, histometrically, histochemically and ultrastructurally. In irradiated rats, the healing process of extraction wound was disturbed. The osteoblastic new bone formation following production of granulation tissue and periosteal new bone formation was interfered. Histochemical examination revealed that the osteoblasts of irradiated rats reduced enzymatic activity compared with control rats. Ultrastructurally, the cytoplasmic organellae were poorly developed in the osteoblasts of irradiated rats and osteoid formation was reduced. In irradiated rats, the osteoclasts in the interradicular alveolar bone were more numerous and increased more rapidly as compared with control rats, whereas, histometrically, there was no significant difference in the amount of bone loss between control and irradiated rats. Histochemically, there was no distinct difference in the enzymatic activity in osteoclasts between control and irradiated rats. Ultrastructurally, the cytoplasmic organellae and ruffled border were poorly developed in the osteoclasts of irradiated rats. The findings suggest that irradiation induced cytological changes in not only oseoblasts but also osteoclasts and these changes resulted in the delayed healing of extraction wound. (author)

Study of LAXS Profile of Hemoglobin from Irradiated Blood

International Nuclear Information System (INIS)

Selim, N.S.; Desouky, O.S.; Elshemey, W.M.

2006-01-01

The present work aims to move a step forward towards a deeper understanding of the scattering of x-ray, from lyophilized biological samples. Comparative study has been performed using low angle x-ray scattering (LAXS) and UV-visible spectrophotometry for monitoring the dose response characteristics of the hemoglobin molecule of irradiated blood. Blood samples were exposed to gamma rays, at doses ranging from 5 up to 100 Gy. Diluted hemoglobin solution was scanned in the UV-visible range (200-700 nm), and lyophilized hemoglobin was prepared for LAXS measurement. The radiation-induced changes in the hemoglobin structure have been evaluated. The LAXS profile of hemoglobin molecule is characterized by the presence of 2 peaks in the forward direction of scattering. These peaks were found to be sensitive to the variations in the molecular structure of a given sample. The obtained results suggest that the 1st peak, recorded at 4.65O (equivalent to momentum transfer, x= 0.526 nm-1), is sensitive to the tertiary and quaternary structure of the globin part, while the major peak, recorded at 10.5O (equivalent to momentum transfer, x= 1.189 nm-1), appeared to be related to its primary and secondary structure

Low energy helium ion irradiation induced nanostructure formation on tungsten surface

International Nuclear Information System (INIS)

Al-Ajlony, A.; Tripathi, J.K.; Hassanein, A.

2017-01-01

We report on the low energy helium ion irradiation induced surface morphology changes on tungsten (W) surfaces under extreme conditions. Surface morphology changes on W surfaces were monitored as a function of helium ion energy (140–300 eV), fluence (2.3 × 10 24 –1.6 × 10 25 ions m −2 ), and flux (2.0 × 10 20 –5.5 × 10 20 ion m −2 s −1 ). All the experiments were performed at 900° C. Our study shows significant effect of all the three ion irradiation parameters (ion flux, fluence, and energy) on the surface morphology. However, the effect of ion flux is more pronounced. Variation of helium ion fluence allows to capture the very early stages of fuzz growth. The observed fuzz growth and morphology changes were understood in the realm of various possible phenomena. The study has relevance and important impact in the current and future nuclear fusion applications. - Highlights: •Reporting formation of W nanostructure (fuzz) due to low energy He ion beam irradiation. •Observing the very early stages for the W-Fuzz formation. •Tracking the surface morphological evolution during the He irradiation. •Discussing in depth our observation and drawing a possible scenario that explain this phenomenon. •Studying various ions irradiation parameters such as flux, fluence, and ions energy.

Experimental studies of free defect generation during irradiation: Implications for reactor environments

International Nuclear Information System (INIS)

Rehn, L.E.; Birtcher, R.C.

1993-01-01

Over the past several years, systematic experiments have revealed that irradiations which generate energetically dense cascades are much less effective than light-ion, MeV electron, or thermal neutron irradiations at producing freely-migrating defects. In this paper, the systematic results on freely-migrating defect production from ion irradiation studies are briefly summarized. Difficulties with applying a simple extrapolation of the ion-irradiation results to neutron environments are discussed. This discussion, coupled with our existing knowledge of neutron-induced property changes, indicates that Compton scattering, and the (n,γ), (n,He) and (n,p) nuclear reactions, are considerably more important for producing freely-migrating defects than was previously realized

Development of system for product tracking and data acquisition of data irradiation process in large gamma irradiators

International Nuclear Information System (INIS)

Soares, Jose Roberto

2010-01-01

The sterilization of medical care products using ionizing radiation is a consolidated technique. In Brazil there are in operation gamma irradiators with capacity between 0.37 PBq (10kCi) 185 PBq (5 MCi) using radioisotopes 60 Co as radiation source. The developed work provides an accurate control and a data acquisition for the application of Good Manufacturing Practices during all phases of an irradiation process, required by the standards of ANVISA, ISO and IAEA technical recommendations for the treatment of foods and medical products. All the steps involved in the irradiation treatment are mapped into process flow (work flow), where each agent (participant) has its systematized tasks. The data acquisition process, monitoring and control, are based on a set of tools (free software licenses) integrated by a network of efficient communication, including the use of Web resources. Using the Gamma Irradiator Multipurpose IPEN/CNEN/USP all the development was performed to be applied in irradiators facilities operating in industrial scale. The system enables a complete traceability of the process, in real time, for any participant and also the storage of the corresponding records to be audited. (author)

Development of system for product tracking and data acquisition of data irradiation process in large gamma irradiators

International Nuclear Information System (INIS)

Soares, Jose R.; Rela, Paulo R.; Costa, Fabio E.

2011-01-01

The sterilization of medical care products using ionizing radiation is a consolidated technique. In Brazil there are in operation gamma irradiators with capacity between 0.37 PBq (10kCi) 185 PBq (5 MCi) using radioisotopes 60 Co as radiation source. The developed work provides an accurate control and data acquisition for the application of good manufacturing practices during all phases of an irradiation process, required by the standards of ANVISA, technical ISO and IAEA recommendations for the treatment of foods and medical products. All the steps involved in the irradiation treatment are mapped into process flow (work flow), where each agent (participant) has its systematized tasks. The automatic data process acquisition using wireless ZigBee technology, monitoring and control, are based on a set of tools (free software licenses) integrated by a network of efficient communication, including the use of Web resources. Using the Gamma Irradiator Multipurpose IPEN/CNEN-SP all the development was performed to be applied in irradiators' facilities operating in industrial scale. The system enables a complete traceability of the process, in real time, for any participant and also the storage of the corresponding records to be audited. (author)

Development of system for product tracking and data acquisition of data irradiation process in large gamma irradiators

Energy Technology Data Exchange (ETDEWEB)

Soares, Jose R., E-mail: joseroberto.soares@mackenzie.br [Universidade Presbiteriana Mackenzie. Escola de Engenharia. Sao Paulo, SP (Brazil); Rela, Paulo R.; Costa, Fabio E., E-mail: prela@ipen.br, E-mail: fecosta@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

2011-07-01

The sterilization of medical care products using ionizing radiation is a consolidated technique. In Brazil there are in operation gamma irradiators with capacity between 0.37 PBq (10kCi) 185 PBq (5 MCi) using radioisotopes {sup 60}Co as radiation source. The developed work provides an accurate control and data acquisition for the application of good manufacturing practices during all phases of an irradiation process, required by the standards of ANVISA, technical ISO and IAEA recommendations for the treatment of foods and medical products. All the steps involved in the irradiation treatment are mapped into process flow (work flow), where each agent (participant) has its systematized tasks. The automatic data process acquisition using wireless ZigBee technology, monitoring and control, are based on a set of tools (free software licenses) integrated by a network of efficient communication, including the use of Web resources. Using the Gamma Irradiator Multipurpose IPEN/CNEN-SP all the development was performed to be applied in irradiators' facilities operating in industrial scale. The system enables a complete traceability of the process, in real time, for any participant and also the storage of the corresponding records to be audited. (author)

White spot syndrome virus inactivation study by using gamma irradiation

Science.gov (United States)

Heidareh, Marzieh; Sedeh, Farahnaz Motamedi; Soltani, Mehdi; Rajabifar, Saeed; Afsharnasab, Mohammad; Dashtiannasab, Aghil

2014-09-01

The present study was conducted to investigate the effect of gamma irradiation on white spot syndrome virus (WSSV). White spot syndrome virus is a pathogen of major economic importance in cultured penaeid shrimp industries. White spot disease can cause mortalities reaching 100% within 3-10 days of gross signs appearing. During the period of culture, immunostimulant agents and vaccines may provide potential methods to protect shrimps from opportunistic and pathogenic microrganisms. In this study, firstly, WSSV was isolated from infected shrimp and then multiplied in crayfish. WSSV was purified from the infected crayfish haemolymph by sucrose gradient and confirmed by transmission electron microscopy. In vivo virus titration was performed in shrimp, Penaeus semisulcatus. The LD50 of live virus stock was calculated 10 5.4/mL. Shrimp post-larvae (1-2 g) were treated with gamma-irradiated (different doses) WSSV (100 to 10-4 dilutions) for a period of 10 days. The dose/survival curve for irradiated and un-irradiated WSSV was drawn; the optimum dose range for inactivation of WSSV and unaltered antigenicity was obtained 14-15 kGy. This preliminary information suggests that shrimp appear to benefit from treatment with gammairradiated WSSV especially at 14-15 KGy.

Experimental studies of the reimplantation of irradiated lung in dogs

Energy Technology Data Exchange (ETDEWEB)

Kondo, T; Fujimura, S; Sohara, Y; Kawakami, M; Okaniwa, G [Tohoku Univ., Sendai (Japan). Research Inst. for Tuberculosis and Cancer

1978-02-01

In order to treat the patients with lung cancer who have impaired cardiopulmonary function, a new method is designed, which includes the following steps; 1) pneumonectomy, 2) resection of tumor-bearing lobe, 3) /sup 60/Co irradiation to the remaining lobe, and 4) orthotopic reimplantation of the irradiated lung. The purpose of present study is to clarify the feasibility to use this method clinically. Using adult mongreal dogs, left lung was excised, irradiated and reimplanted. Radiation was carried out from 2,000 rad to 4,000 rad. Viability and function of reimplanted lungs were evaluated by their survival time, serial chest x-ray films, sup(99m)Tc-MAA perfusion scanning, unilateral pulmonary artery occlusion test and histologic examinations. Of 17 animals, 12 survived postoperative period and following results were obtained; 1) no dogs developed pulmonary edema, 2) only one dog was considered to die from acute radiation pneumonitis, 3) serial perfusion scanning showed a gradual decrease in flow distribution to the transplanted lung, 4) the right pulmonary occlusion test done in the dog irradiated with 2,000 rad revealed well reserved pulmonary function 2 months after the operation, and 5) histologically, most irradiated lungs revealed so-called ''late reaction'' of lung fibrosis, but there was the case with nearly normal findings after 6 months from the operation. Although many reports concerning to the radiation pneumonitis are published, there have not been any such reports as the present study. From our experiment, it may be indicated that there is a feasibility to use this new method clinically.

An experimental study of the irradiation effects on rat parotid gland

International Nuclear Information System (INIS)

Lee, Kyu Chan; Lee, Sang Rae

1986-01-01

This study was designed to investigate the irradiation effects on the rat parotid gland, applied to the head and neck region. For this experiment, twenty-four rat, feeded under the even condition, were used as experimental animals. Twenty rat were used for experimental group and the rest were assigned to the control group. The experimental group was singly irradiated with 10 Gray through Cobalt-60 radiotherapy device, Pickre model 4M 60 (Field size; 12x5 cm, SSD; 50 cm, Depth; 1 cm). The experimental animals of both group were sacrificed each four animals in 2 days, 1 week, 2 weeks, 3 weeks and 4 weeks after irradiation. The specimens were examined through the light microscope using the H-E stain and H stain by routine procedure. The other specimens were observed under the fluorescence microscope using the B-O dichroic mirror and Y 45 5 barrier filter after PA-ACH stain. The results of this study were obtained as follows: 1. The parotid acini were severely degenerated and intraacinar space were widened. Within the acini, retained secretory granules and increased fibrosis were observed. Also the shape and the size of the acini showed very irregular atrophic degeneration. 2. The nuclei showed severe pyknosis, displacement and irregular aggregated appearance. 3. The tissue changes of the parotid acini were initiated after 2 days of irradiation and most severely appeared at the second week of irradiation, but almost returned to normal. 4. The salivary ducts of the parotid gland were severely atrophied, discontinued but initiated to regenerated after 3 weeks of irradiation.

Design considerations and operating experience with wet storage of Ontario Hydro's irradiated fuel

International Nuclear Information System (INIS)

Frost, C.R.; Naqvi, S.J.; McEachran, R.A.

1987-01-01

The characteristics of Ontario Hydro's fuel and at-reactor irradiated fuel storage water pools (or irradiated fuel bays) are described. There are two types of bay known respectively as primary bays and auxiliary bays, used for at-reactor irradiated fuel storage. Irradiated fuel is discharged remotely from Ontario Hydro's reactors to the primary bays for initial storage and cooling. The auxiliary bays are used to receive and store fuel after its initial cooling in the primary bay, and provide additional storage capacity as needed. The major considerations in irradiated fuel bay design, including site-specific requirements, reliability and quality assurance, are discussed. The monitoring of critical fuel bay components, such as bay liners, the development of high storage density fuel containers, and the use of several irradiated fuel bays at each reactor site have all contributed to the safe handling of the large quantities of irradiated fuel over a period of about 25 years. Routine operation of the irradiated fuel bays and some unusual bay operational events are described. For safety considerations, the irradiated fuel in storage must retain its integrity. Also, as fuel storage is an interim process, likely for 50 years or more, the irradiated fuel should be retrievable for downstream fuel management phases such as reprocessing or disposal. A long-term experimental program is being used to monitor the integrity of irradiated fuel in long-term wet storage. The well characterized fuel, some of which has been in wet storage since 1962 is periodically examined for possible deterioration. The evidence from this program indicates that there will be no significant change in irradiated fuel integrity (and retrievability) over a 50 year wet storage period

AGR-1 Irradiation Test Final As-Run Report, Rev. 3

Energy Technology Data Exchange (ETDEWEB)

Collin, Blaise P. [Idaho National Lab. (INL), Idaho Falls, ID (United States)

2015-01-01

This document presents the as-run analysis of the AGR-1 irradiation experiment. AGR-1 is the first of eight planned irradiations for the Advanced Gas Reactor (AGR) Fuel Development and Qualification Program. Funding for this program is provided by the US Department of Energy (DOE) as part of the Next-Generation Nuclear Plant (NGNP) project. The objectives of the AGR-1 experiment are: 1. To gain experience with multi-capsule test train design, fabrication, and operation with the intent to reduce the probability of capsule or test train failure in subsequent irradiation tests. 2. To irradiate fuel produced in conjunction with the AGR fuel process development effort. 3. To provide data that will support the development of an understanding of the relationship between fuel fabrication processes, fuel product properties, and irradiation performance. In order to achieve the test objectives, the AGR-1 experiment was irradiated in the B-10 position of the Advanced Test Reactor (ATR) at the Idaho National Laboratory (INL) for a total duration of 620 effective full power days of irradiation. Irradiation began on December 24, 2006 and ended on November 6, 2009 spanning 13 ATR cycles and approximately three calendar years. The test contained six independently controlled and monitored capsules. Each capsule contained 12 compacts of a single type, or variant, of the AGR coated fuel. No fuel particles failed during the AGR-1 irradiation. Final burnup values on a per compact basis ranged from 11.5 to 19.6 %FIMA, while fast fluence values ranged from 2.21 to 4.39 x 10²⁵ n/m² (E >0.18 MeV). We’ll say something here about temperatures once thermal recalc is done. Thermocouples performed well, failing at a lower rate than expected. At the end of the irradiation, nine of the originally-planned 19 TCs were considered functional. Fission product release-to-birth (R/B) ratios were quite low. In most capsules, R/B values at the end of the irradiation were at or below

Study of irradiation effects in non-metallic conductors

International Nuclear Information System (INIS)

Atobe, Kozo; Fukuoka, Noboru; Honda, Makoto; Kondo, Tadashi; Morishima, Kouichi; Okada, Moritami; Nakagawa, Masuo

1998-01-01

The production of point defects induced by reactor and the thermal behavior of defects in sintered AlN and c-BN have been investigated using the optical absorption and electron spin resonance (ESR) methods. The absorption band at 370 nm (AlN) and the structureless absorption over the visible region are observed. These specimens also show ESR signals with g-value 2.007 (AlN), 2.006 (BN), which are probably caused by N vacancies with a trapped electron. In addition to these experiments, the difference of the photoluminescence(PL) lines on neutron irradiated CZ-Si and FZ-Si has been also studied. The models of the defect associated with neutron irradiation are discussed. (author)

Study by internal friction of curing low temperature irradiation defects in graphite

International Nuclear Information System (INIS)

Rouby, Dominique.

1974-01-01

Micromechanical properties and anelastic effects of neutrons irradiated graphites at 300 and 77 0 K are investigated by internal friction analysis and elasticity modulus variations. Defects created by irradiation are studied and evolution versus dose and annealing is followed [fr

Histopathological studies on the effects of preoperative irradiation for cancer of the esophagus

International Nuclear Information System (INIS)

Goseki, Narihide

1979-01-01

Though a criterion for histopathological changes by radiotherapy was determined by the study group of esophageal diseases, this criterion is not always compatible with clinical findings and prognosis of each patient. To review this point again, degenerative changes in esophageal cancer cells due to irradiation and the distribution of cancer cells in the esophageal wall were observed. To evaluate the Ef classification of esophageal cancer, histopathological studies of resected en bloc specimens from 36 patients with advanced esophageal cancer who had received preoperative irradiation were performed. Cancer cells with slight degeneration distributed around the cancer lesions in 29 cases (81%). This result indicates that it is not accurate to evaluate the effect of radiation histopathologically, based upon the Ef classification, unless the en bloc segmented specimens are prepared. Histopathological evaluation of effects of irradiation indicated that effective rate of irradiation were significantly higher when total dose of over 4,000 rad was irradiated and the intervals between irradiation and surgery were within 20 days. In 16 of 20 patients in whom cancer cells with slight degeneration (d 1 ) were observed, cancer cells with degenerative changes of d 1 grade still remained in the adventitia, and expected improvement of a-factor by irradiation was observed in less cases than previously reported. (Tsunoda, M.)

In Vitro UV-Visible Spectroscopy Study of Yellow Laser Irradiation on Human Blood

Science.gov (United States)

Fuad, Siti Sakinah Mohd; Suardi, N.; Mustafa, I. S.

2018-04-01

This experimental study was performed to investigate the effect of low level yellow laser of 589nm wavelength with various laser irradiation time. Human blood samples with random diseases are irradiated with yellow laser of power density of 450mW/cm2 from 10 minutes to 60 minutes at 10 minutes intervals. The morphology of the red blood cell were also observed for different irradiation time. The result shows that there is a significant different in the absorption of light with varying laser irradiation time (p<0.01). The maximum absorption recorded at 40 minutes of irradiation at 340nm peak. Blood smear of the samples reveals that there are observable changes in the morphology of the red blood cell at 40 minutes and 60 minutes of irradiation.

Studies on Microbiological and Biological Methods for Detection of Irradiated Food

International Nuclear Information System (INIS)

Ibrahim, H.M.A.

2013-01-01

The main aim of this study is to evaluate a microbiological and biological methods used for the detection of irradiated foods in Egypt. The microbiological methods included were shift in microflora load and direct epifluroescent filter technique compared with aerobic plate count (DEFT/APC), while the biological method was DNA comet assay. The selected foods were black, strawberry, fresh-and frozen-de boned chicken. The samples of these foods were exposed to different doses of gamma radiation according to the purpose of irradiation for each food. The results indicated that the characteristics of microbial population of all irradiated samples have been changed. The very lower count of viable bacterial count (APC) and mold and yeasts counts in the samples than the reported normal count as well as the absence of Gram- negative bacteria and Enterobacteriaceae group from these samples could be used as an indication for radiation treatment of these foods. The large difference between microbial counts obtained by DEFT test and that obtained by APC test could also be used for screening radiation treatment of these foods. Photographic and image analysis of DNA comet assay showed that irradiation of these foods caused damage to the food cells DNA (fragmentation) at different levels according to the doses used and kind of foods. This DNA damage can be followed or described by DNA comet assay test. On the basis of comet assay, the discrimination between unirradiated and irradiated food samples was very possible. In general the results showed that DEFT/APC method had the potential to detect irradiated food samples either at zero time of storage or throughout the storage period post- irradiation. DNA comet assay as a rapid, simple and inexpensive screening test approved to be successful for detection of irradiated food samples under investigation. Determination of rough applied irradiation dose is possible if photographic analysis is combined with image analysis

A Study on Structural Strength of Irradiated Spacer Grid for PWR Fuel

Energy Technology Data Exchange (ETDEWEB)

Jin, Y. G.; Baek, S. J.; Kim, D. S.; Yoo, B. O.; Ahn, S. B.; Chun, Y. B. [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of); Kim, J. I.; Kim, Y. H.; Lee, J. J. [KEPCO NF, Daejeon (Korea, Republic of)

2014-10-15

A fuel assembly consists of an array of fuel rods, spacer grids, guide thimbles, instrumentation tubes, and top and bottom nozzles. In PWR (Pressurized light Water Reactor) fuel assemblies, the spacer grids support the fuel rods by the friction forces between the fuel rods and springs/dimples. Under irradiation, the spacer grids supporting the fuel rods absorb vibration impacts due to the reactor coolant flow, and also bear static and dynamic loads during operation inside the nuclear reactor and transportation for spent fuel storage. Thus, it is important to understand the characteristics of deformation behavior and the change in structural strength of an irradiated spacer grid.. In the present study, the static compression test of a spacer grid was conducted to investigate the structural strength of the irradiated spacer grid in a hot cell at IMEF (Irradiated Materials Examination Facility) of KAERI. To evaluate the structural strength of an irradiated spacer grid, hot cell tests were carried out at IMEF of KAERI. The fuel assembly was dismantled and the irradiated spacer grid was obtained for the compression test. The apparatus for measuring the compression strength of the irradiated spacer grid was developed and installed successfully in the hot cell.

Studies on the improvement of irradiation process

International Nuclear Information System (INIS)

Kim, Ki Yup; Pyun, Hyung Chick; Yoon, Byung Mok; Nho, Young Chang; Lee, Young Keun; Park, Soon Chul; Na, Bong Joo; Yoo, Young Soo

1991-01-01

On the basis of analysis and examination for efficient maintenance and operation of the facility, the method of improving irradiation process was discussed so that we may extend the applicability of irradiation technique to various materials and accelerate nation-wide propagation of radiation processing technology. Preparations have been made for transfer, installation, and operation of the irradiation facilities in radiation application building which will be completed at the headquarter site by the end of 1992. The qualification testing apparatus for nuclear power station cables was conceptually designed to investigate the degradation behavior of the cables under a simulated LOCA(Loss of Coolant Accident) environments. (Author)

Irradiation effect on antifungal potential Myristica fragrans (nutmeg) essential oil, a preliminary study

International Nuclear Information System (INIS)

Duarte, Renato C.; Fanaro, Gustavo B.; Koike, Amanda C.R.; Villavicencio, Anna Lucia C.H.

2011-01-01

The Myristica fragrans (nutmeg) is any of several species of trees in genus Myristica. The most important commercial species is Myristica fragrans, an evergreen tree indigenous to the Banda Islands in the Moluccas of Indonesia, or Spice Islands. Widely used as a food condiment and flavoring, used in perfumery and medicine. The nutmeg has many biological properties as analgesic, antiseptic, antispasmodic, aphrodisiac, astringent, carminative, haemostatic, insecticidal and parasiticide. Previous research has revealed interesting antimicrobial effect of nutmeg essential oil. Spices irradiation is a worldwide process used and this technique is an effective pathogenic microorganisms control providing consumers food security. By the fact nutmeg not only used in food, but also as an essential oil raw material this study investigated the nutmeg different irradiation doses influence on the possible antimicrobial potential oil. The aim of this study was evaluate the antifungal potential oil from unirradiated and irradiated nutmeg in the fungus Guignardia citricarpa that causes serious damage in orange plantations. The Myristica fragrans samples were irradiated in 60 Co irradiator at doses of 5.0 and 10.0 kGy. The oil was used in 50 and 100% of concentration (irradiated and not irradiated). The essential oil in high concentration could be a good substitute for the pesticides used to control the fungus Guignardia citricarpa, the nutmeg irradiation treatment with the doses 5.0 and 10.0 kGy did not changed the results in the essential oil effectiveness. It is clear that is necessary others studies with others doses to verify the radiation ionizing influence in the essential oil activity and the oil application efficiency in the field against the fungus. (author)

Irradiation effect on antifungal potential Myristica fragrans (nutmeg) essential oil, a preliminary study

Energy Technology Data Exchange (ETDEWEB)

Duarte, Renato C.; Fanaro, Gustavo B.; Koike, Amanda C.R.; Villavicencio, Anna Lucia C.H., E-mail: gbfanaro@ipen.b, E-mail: amandaramos@usp.b, E-mail: villavic@ipen.b [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

2011-07-01

The Myristica fragrans (nutmeg) is any of several species of trees in genus Myristica. The most important commercial species is Myristica fragrans, an evergreen tree indigenous to the Banda Islands in the Moluccas of Indonesia, or Spice Islands. Widely used as a food condiment and flavoring, used in perfumery and medicine. The nutmeg has many biological properties as analgesic, antiseptic, antispasmodic, aphrodisiac, astringent, carminative, haemostatic, insecticidal and parasiticide. Previous research has revealed interesting antimicrobial effect of nutmeg essential oil. Spices irradiation is a worldwide process used and this technique is an effective pathogenic microorganisms control providing consumers food security. By the fact nutmeg not only used in food, but also as an essential oil raw material this study investigated the nutmeg different irradiation doses influence on the possible antimicrobial potential oil. The aim of this study was evaluate the antifungal potential oil from unirradiated and irradiated nutmeg in the fungus Guignardia citricarpa that causes serious damage in orange plantations. The Myristica fragrans samples were irradiated in {sup 60}Co irradiator at doses of 5.0 and 10.0 kGy. The oil was used in 50 and 100% of concentration (irradiated and not irradiated). The essential oil in high concentration could be a good substitute for the pesticides used to control the fungus Guignardia citricarpa, the nutmeg irradiation treatment with the doses 5.0 and 10.0 kGy did not changed the results in the essential oil effectiveness. It is clear that is necessary others studies with others doses to verify the radiation ionizing influence in the essential oil activity and the oil application efficiency in the field against the fungus. (author)

Commercial scale irradiation for insect disinfestation preserves peach quality

International Nuclear Information System (INIS)

McDonald, Heather; McCulloch, Mary; Caporaso, Fred; Winborne, Ian; Oubichon, Michon; Rakovski, Cyril; Prakash, Anuradha

2012-01-01

Irradiation is approved as a generic quarantine treatment by the US Department of Agriculture, Animal and Plant Health Inspection Service. Due to the effectiveness of irradiation in controlling insects on commodities, there is a growing need to understand the effects of low dose irradiation on fruit quality. The goal of this study was to determine the sensitivity of peaches (Prunus persica) to irradiation, and secondly, to determine the effect of commercial scale treatment on shelf-life, overall quality and consumer liking. Six varieties of peaches were irradiated in small batches at 0.29, 0.49, 0.69 and 0.90 kGy to observe the sensitivity of peaches at different dose levels. Changes in quality were evaluated by 8 trained panelists using descriptive analysis. Sensory characteristics (color, smoothness, aroma, touch firmness, mouth firmness, graininess, overall flavor and off-flavor) were evaluated at 2–4 day intervals and untreated samples served as control. To simulate commercial treatment, peaches were irradiated in pallet quantities at a target dose level of 0.4 kGy. The average absorbed dose was 0.66 kGy with an average dose uniformity ratio of 1.57. Commercially treated peaches were evaluated by 40–80 untrained consumers for acceptability routinely throughout the shelf life. Titratable acidity, Brix, texture and weight loss were also monitored for both commercial and small scale irradiated peaches. There was no dose effect on TA, Brix and weight loss due to irradiation. Peaches irradiated at 0.69 and 0.90 kGy were darker in flesh color, more juicy and less firm as determined by the trained panel and analytical pressure tests. Commercial scale irradiation did not adversely affect shelf life but was seen to enhance ripening. This, however, was perceived as a positive change by consumers. Overall, consumers rated the acceptability of irradiated peaches higher than untreated peaches. Statistical analysis was performed using linear mixed models to find

Physicochemical studies for detection of irradiated dry date fruits

International Nuclear Information System (INIS)

Farag, S.E.A.; El-Salhy, F.T.; Nassef, A.E.; El-beltagy, A.E.; Moharram, H.A.

2005-01-01

The kinetic of the water absorption properties of a selected varieties from the Egyptian dry date fruits were carried out. Sakoti, shamia bida, sokaria, candela and malkabee varieties were used to get an idea about their water absorption properties. Malkabee variety was selected for irradiation at different doses of 0.5, 1, 2, 3, 4 and 5 KGy. In order to obtain a fast, reliable and easy techniques for detecting irradiated dates, several physico-chemical and ultrastructural properties were elucidated in this investigation. Regarding to water absorption, the statistical analysis of the water absorption data revealed that, the amount of water absorption (g water/g dry solid) was decreased with increasing the irradiation doses. This phenomena was confirmed when SEM technique was applied, since irradiation caused shrinkage and reduction in the inner cells. The colour indices were measured by colour analyzer (hunter colorimeter). An inversely proportional relationship was observed between the hue angle and the progress in the irradiation dose, In contrast, direct proportional relationship is strongly observed when the color combination a/b was measured. From the chemical analysis point of view, it was observed that irradiation lowered the amount of total sugars by enhanced reducing sugars. From elucidating the physico-chemical properties of the irradiation date palm, it is now possible to establish a stainable fast, reliable and cheap detection method that could be used to distinguish between the irradiated and non-irradiated dry date fruits

Studies on sprout inhibition of onions by gamma irradiation

International Nuclear Information System (INIS)

Thomas, P.; Srirangarajan, A.N.; Limaye, S.P.

1975-01-01

Sprout inhibition of onions by gamma irradiation was found to be influenced by the physiological state of the bulbs at the time of irradiation, radiation dose and the storage temperature after irradiation. Sprouting was minimal during storage at ambient temperature (26 to 32 0 C) while exposure to low temperature (4 to 20 0 C) or widely fluctuating diernal temperature (20 0 C min to 30 0 C max) accelerated it. Six to nine Krad inhibited sprouting during storage under the above conditions only if the bulbs were irradiated within a fortnight of harvest when they were in the dormant state. Twenty-five Krad caused a transient stimulation of sprouting regardless of the time of irradiation while 6 to 12 Krad only stimulated sprouting when the time interval between harvest and irradiation exceeded three weeks. Irradiation at all dose levels cause discoloration of the growth centre, the extent of which was minimal in bulbs exposed to low doses soon after harvest and in those stored at ambient temperature. (author)

Photo irradiation Systems for In-Vitro Cultured Cells Phototherapy and Photobiology Experiments

International Nuclear Information System (INIS)

Serrano Navarro, Joel; Morales Lopez, Orestes M.; Hernandez Quintanas, Luis F.; Lopez Silva, Y.; Fabila Bustos, Diego A.; De la Rosa Vazquez, Jose M.; Valor Reed, Alma; Stolik Isakina, Suren; Brodin, Patrik N.; Guha, Chandan; Tome, Wolfgang A.

2016-01-01

The increase in research and application of various phototherapy methods, especially photodynamic therapy (PDT) has created the need to study in depth the mechanisms of interaction of light with biological tissue using a photosensitizing drug in order to increase the therapeutic effectiveness. In this issue, two systems for controlled irradiation of in-vitro cell culture and temperature monitoring of the culture are presented. The first system was designed to irradiate 24 wells in a 96-well microplate. The second one was constructed for the irradiation and control of a 24-well microplate using larger volumes of cultured cells. Both systems can independently irradiate and control the temperature of each well. The systems include a module for contactless measurement of the temperature in each well. Light sources are located in an interchangeable module, so that it can be replaced to irradiate with different wavelengths. These prototypes count with various operation modes, controlled by a computer, which permits establishing specific settings in accordance with the desired experiment. The systems allow the automated experiment execution with precise control of dosimetry, irradiation and temperature, which reduces the sample-handling while, saves time. (Author)

Microbiological studies for the detection of irradiated food

International Nuclear Information System (INIS)

Abd-Elbary, N.A.

2001-01-01

the exposure of food to ionizing radiation is being progressively used in many countries to inactivate food pathogens, to eradicate pests, and to extend shelf life, thereby contributing to a safer and more plentiful food supply. to ensure free consumer choice, irradiated food will be labeled as such, and to enforce labeling, analytical methods to detect the irradiation treatment in the food product itself are desirable, in particular, there is a need for simple and rapid screening methods for the control of irradiated food.this investigation has been carried out in an effect to design reliable methods for detecting whether or not a food has been irradiated . attempts have been made to apply microbiological and biological form measurement

Experimental study of swelling of irradiated solid methane during annealing

International Nuclear Information System (INIS)

Shabalin, E.; Fedorov, A.; Kulagin, E.; Kulikov, S.; Melikhov, V.; Shabalin, D.

2008-01-01

Solid methane, notwithstanding its poor radiation properties, is still widely in use at pulsed neutron sources. One of the specific problems is radiolytic hydrogen gas pressure on the walls of a methane chamber during annealing of methane. Results of experimental study of this phenomenon under fast neutron irradiation with the help of a specially made low temperature irradiation rig at the IBR-2 pulsed reactor are presented. Peak pressure on the wall of the experimental capsule during heating of a sample irradiated at 23-35 K appeared to have a maximum of 27 bar at the absorbed dose 20 MGy, and then falls down with higher doses. Pressure always reached its peak value within the temperature range 72-79 K. Generally, three phases of methane swelling during heating can be distinguished, each characterized by proper rate and intensity. Results of this study were accounted for in design of the solid methane moderator of the second target station of the ISIS facility (England)

Fusion neutron irradiation of Ni(Si) alloys at high temperature

International Nuclear Information System (INIS)

Huang, J.S.; Guinan, M.W.; Hahn, P.A.

1987-09-01

Two Ni-4% Si alloys, with different cold work levels, are irradiated with 14 MeV fusion neutrons at 623 K, and their Curie temperatures are monitored during irradiation. The results are compared to those of an identical alloy irradiated by 2 MeV electrons. The results show that increasing dislocation density increases the Curie temperature change rate. At the same damage rate, the Curie temperature change rate for the alloy irradiated by 14 MeV fusion neutrons is only 6 to 7% of that for an identical alloy irradiated by 2 MeV electrons. It is well known that the migration of radiation induced defects contributes to segregation of silicon atoms at sinks in this alloy, causing the Curie temperature changes. The current results imply that the relative free defect production efficiency decreases from one for the electron irradiated sample to 6 to 7% for the fusion neutron irradiated sample. 17 refs., 4 figs., 1 tab

Fusion neutron irradiation of Ni(Si) alloys at high temperature

Energy Technology Data Exchange (ETDEWEB)

Huang, J.S.; Guinan, M.W.; Hahn, P.A.

1987-09-01

Two Ni-4% Si alloys, with different cold work levels, are irradiated with 14 MeV fusion neutrons at 623 K, and their Curie temperatures are monitored during irradiation. The results are compared to those of an identical alloy irradiated by 2 MeV electrons. The results show that increasing dislocation density increases the Curie temperature change rate. At the same damage rate, the Curie temperature change rate for the alloy irradiated by 14 MeV fusion neutrons is only 6 to 7% of that for an identical alloy irradiated by 2 MeV electrons. It is well known that the migration of radiation induced defects contributes to segregation of silicon atoms at sinks in this alloy, causing the Curie temperature changes. The current results imply that the relative free defect production efficiency decreases from one for the electron irradiated sample to 6 to 7% for the fusion neutron irradiated sample. 17 refs., 4 figs., 1 tab.

Linear accelerator calibration monitor with a memory

International Nuclear Information System (INIS)

Dixon, R.L.; Ekstrand, K.E.

1979-01-01

A calibration monitor has been designed for measuring the constancy of linear accelerator or cobalt unit output between full calibrations. This monitor is battery-operated, light-weight, and slides into the shadow tray attachment on a linear accelerator or cobalt unit for easy setup. It provides a digital readout of the dose delivered, and a consistency check can be made in less than two minutes. The precision of the monitor, determined by cobalt-60 irradiations over a 2 1/2 month period, is +- 0.6% (standard deviation). The monitor also retains the dose reading in a CMOS digital counter indefinitely, hence it can be used in the same fashion as mailed thermoluminescent dosimeters (TLD) for calibration checks at remote facilities without the complicated readout procedures associated with TLD. The monitor can be mailed to a remote facility, positioned without ambiguity, and irradiated; and the reading can be verified on return to the originating center simply by pressing a switch. The monitor can easily be set up to carry out a ''blind'' check in which the reading obtained is not known to the remote facility

Experimental study on an active specific immunotherapy modified with irradiation, 1

International Nuclear Information System (INIS)

Ogawa, Yasuhiro; Takashima, Hitoshi; Imanaka, Kazufumi

1982-01-01

Active specific immunotherapy using low-dose-irradiated tumor cells and activated mononuclear cells was studied on the transplanted MM 46 tumor of female C3H/He mice aged 12 weeks, after radiotherapy was performed. Local irradiation with the dose of 3,000 rads by high energy electron beam was performed on the fifth day after 5 x 10 6 tumor cells were inoculated in the right hind paws. Tumor cells and mononuclear cells were separated from the tumor tissue which was irradiated with the dose of 2,000 rads on the fifth day and were injected subcutaneously into the left hind paws of the tumor burden mice on the eleventh day. Anti-tumor effect was evaluated by the changes of the tumor volume and survival curves. Tumor growth was significantly inhibited in the group which received irradiation combined with active specific immunotherapy compared with the control group (p < 0.01). Survival rate was significantly higher in the group which received irradiation combined with active specific immunotherapy than the control group (p < 0.025). (author)

Evaluation of gamma irradiation of teas

Energy Technology Data Exchange (ETDEWEB)

Gerolis, Luanai G.L.; Lameiras, Fernando S.; Menezes, Maria A.B.C.; Leal, Alexandre S., E-mail: luanaigraz@yahoo.com.br [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil); Krambrock, Klaus, E-mail: klaus@fisica.ufmg.br [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil). Dept. de Fisica. Lab. de Ressonancia Paramagnetica Eletronica

2013-07-01

There is a growing interest in the determination of non-essential traces elements in agroindustrial products. The continuous ingestion and accumulation in the organism of such elements, that may be toxic, can cause hazards to the human health in the long term. Reliable analytical techniques are necessary to monitor such products, including teas. In this work, the neutron activation technique is being employed to determine the trace elements in teas, due to its high sensibility and the possibility to perform a multi-elementary analysis. The gamma irradiation of teas is also being studied, because the shelf life can be extended and no chemical product is added to the teas. There is a concern related to the formation of free radicals in the teas, which is being accessed with electronic paramagnetic resonance. The results of the gamma irradiation up to 20 kGy of Camelia sinensis, Ilex paraguariensis, and Matricaria recutita are presented. (author)

Evaluation of gamma irradiation of teas

International Nuclear Information System (INIS)

Gerolis, Luanai G.L.; Lameiras, Fernando S.; Menezes, Maria A.B.C.; Leal, Alexandre S.; Krambrock, Klaus

2013-01-01

There is a growing interest in the determination of non-essential traces elements in agroindustrial products. The continuous ingestion and accumulation in the organism of such elements, that may be toxic, can cause hazards to the human health in the long term. Reliable analytical techniques are necessary to monitor such products, including teas. In this work, the neutron activation technique is being employed to determine the trace elements in teas, due to its high sensibility and the possibility to perform a multi-elementary analysis. The gamma irradiation of teas is also being studied, because the shelf life can be extended and no chemical product is added to the teas. There is a concern related to the formation of free radicals in the teas, which is being accessed with electronic paramagnetic resonance. The results of the gamma irradiation up to 20 kGy of Camelia sinensis, Ilex paraguariensis, and Matricaria recutita are presented. (author)

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.

An experimental studies of skin autograft in irradiated bed

International Nuclear Information System (INIS)

Ueda, Minoru

1981-01-01

Effects of irradiation to revascularization and skin grafting were studied. Wistar rats were irradiated with 1000, 2000, and 3000 rad of x-ray. One 2, 4, 6, 8, 12, and 24 weeks after irradiation each group, consisted of 10 rats, was compared with that of 34 untreated rats. A new score system of skin reaction was proposed. The highest moist skin reaction was observed after 2 weeks in 3 irradiated groups. In the 2000 and 3000 rad groups, the acute reaction appeared with 1 week latent period and recovered in 8 weeks followed by marked skin atrophy and epilation, while in the 1000 rad group complete recovery was observed in 3 weeks without late squlae. In order to carry out microangiography, a new device to inject the contrast medium at constant temperature and pressure was used. Marked inflammation was observed in 4 weeks, began to recover in 4 weeks, and hypovascular area appeared in 8 weeks. As for the blood area density, no variation was found for the 1000 rad group. However, in the 2000 and 3000 rad groups, the highest density was observed in 2 weeks and decreased after 8 weeks to that lower than the control. Revascularization after the skin grafting was followed by microangiography. In the control group, primary and secondary revascularization was observed one and 3 days after transplantation. As for the 3000 rad groups both revascularizations were hardly recognized when transplanted 8 weeks after irradiation. The optimum time for skin grafting was found to be acute or subacute period of the vascular damage. (Nakanishi, T.)

Stability Studies of Certain Chemotherapeutic Agents Following Gamma Irradiation and Silver Nanoparticles Conjugation

International Nuclear Information System (INIS)

El-Sayyad, Gh.E.S.M.

2014-01-01

The Chemical stability of drug is of great importance since it becomes less effective as it undergoes degradation in case of applied of gamma irradiation process. The application of gamma irradiation for different chemotherapeutic agents Such as (ofloxacin, sodium ampicillin, sodium cefotaxime, gentamycin and amoxicillin) and studying the effect of applied doses on chemical structure and biological activity of the irradiated antibiotics compared to unirradiated ones was studied by ultraviolet-Visible spectrophotometer (UV-Visible), Fourier transform infrared spectroscopy measurements (FTIR spectra) and high performance liquid chromatography (HPLC) in addition to microbiological assay were run before and after irradiation to probe any change after irradiation. The results showed that all of the irradiated compounds remain stable and radio resistant; retaining their structure and activity unchanged up to 25 KGy. The radiation-induced AgNPs synthesis is a simple, clean which involves radiolysis of aqueous solution that provides an efficient method to reduce metal ions. Also, in this study, Bacillus megaterium was found to be an effective biological tool for the extracellular biosynthesis of stable AgNPs which are highly stable and this method has advantages over other methods as the organism used here is safe. This study would therefore lead to an easy procedure for producing silver nanoparticles with the added advantage of bio safety. The Synthesized AgNPs exhibit remarkable antimicrobial activity against both Gram-positive and Gram negative bacterial strains regardless of their drug-resistant mechanisms. The bactericidal activity have proved that AgNPs kill bacteria at such low concentrations (units of ppm), which Stability Studies of Certain Chemotherapeutic Agents Following Gamma Irradiation and Silver Nanoparticles Conjugation. do not reveal acute toxic effects on human cell, in addition to overcoming resistance, and lowering cost when compared to conventional

Performance of silicon pad detectors after mixed irradiations with neutrons and fast charged hadrons

Energy Technology Data Exchange (ETDEWEB)

Kramberger, G. [Jozef Stefan Institute, Department of Physics, University of Ljubljana, Jamova 39, SI-1000 Ljubljana (Slovenia)], E-mail: Gregor.Kramberger@ijs.si; Cindro, V.; Dolenc, I.; Mandic, I.; Mikuz, M.; Zavrtanik, M. [Jozef Stefan Institute, Department of Physics, University of Ljubljana, Jamova 39, SI-1000 Ljubljana (Slovenia)

2009-10-11

A large set of silicon pad detectors produced on MCz and FZ wafer of p- and n-type was irradiated in two steps, first by fast charged hadrons followed by reactor neutrons. In this way the irradiations resemble the real irradiation fields at LHC. After irradiations controlled annealing started in steps during which the evolution of full depletion voltage, leakage current and charge collection efficiency was monitored. The damage introduced by different irradiation particles was found to be additive. The most striking consequence of that is a decrease of the full depletion voltage for n-type MCz detectors after additional neutron irradiation. This confirms that effective donors introduced by charged hadron irradiation are compensated by acceptors from neutron irradiation.

Performance of silicon pad detectors after mixed irradiations with neutrons and fast charged hadrons

International Nuclear Information System (INIS)

Kramberger, G.; Cindro, V.; Dolenc, I.; Mandic, I.; Mikuz, M.; Zavrtanik, M.

2009-01-01

A large set of silicon pad detectors produced on MCz and FZ wafer of p- and n-type was irradiated in two steps, first by fast charged hadrons followed by reactor neutrons. In this way the irradiations resemble the real irradiation fields at LHC. After irradiations controlled annealing started in steps during which the evolution of full depletion voltage, leakage current and charge collection efficiency was monitored. The damage introduced by different irradiation particles was found to be additive. The most striking consequence of that is a decrease of the full depletion voltage for n-type MCz detectors after additional neutron irradiation. This confirms that effective donors introduced by charged hadron irradiation are compensated by acceptors from neutron irradiation.

Study of irradiated bone: Part III. /sup 99m/Tc pyrophosphate autoradiographic changes

International Nuclear Information System (INIS)

King, M.A.; Corriveau, O.; Casarett, G.W.; Weber, D.A.

1978-01-01

The macroautoradiographic and microautoradiographic localization of /sup 99m/Tc-pyrophosphate (/sup 99m/TcPPi) was studied in x-irradiated bone of rabbits up to one year post-irradiation. In cortical bone, /sup 99m/TcPPi was concentrated on bone surfaces near vasculature. Both forming and resorbing bone surfaces were comparably labeled at 2 hrs post-injection. Uptake on the surface of sites of haversian bone remodeling was observed to be at least part of the increased /sup 99m/TcPPi observed in irradiated bone in camera images. In irradiated trabecular bone 12 months following irradiation, a patchy decrease in /sup 99m/TcPPi uptake was correlated with localized decreases in vasculature

Irradiation chamber and sample changer for biological samples

International Nuclear Information System (INIS)

Kraft, G.; Daues, H.W.; Fischer, B.; Kopf, U.; Liebold, H.P.; Quis, D.; Stelzer, H.; Kiefer, J.; Schoepfer, F.; Schneider, E.

1980-01-01

This paper describes an irradiaton system with which living cells of different origin are irradiated with heavy ion beams (18 <- Z <- 92) at energies up to 10 MeV/amu. The system consists of a beam monitor connected to the vacuum system of the accelerator and the irradiation chamber, containing the biological samples under atmospheric pressure. The requirements and aims of the set up are discussed. The first results with saccharomyces cerevisiae and Chinese Hamster tissue cells are presented. (orig.)

New temperature monitoring devices for high-temperature irradiation experiments in the high flux reactor Petten

Energy Technology Data Exchange (ETDEWEB)

Laurie, M.; Futterer, M. A.; Lapetite, J. M. [European Commission Joint Research Centre, Institute for Energy, P.O. Box 2, NL-1755 ZG Petten (Netherlands); Fourrez, S. [THERMOCOAX SAS, BP 26, Planquivon, 61438 Flers Cedex (France); Morice, R. [Laboratoire National de Metrologie et d' Essais, 1 rue Gaston Boissier, 75724 Paris (France)

2009-07-01

Within the European High Temperature Reactor Technology Network (HTR-TN) and related projects a number of HTR fuel irradiations are planned in the High Flux Reactor Petten (HFR), The Netherlands, with the objective to explore the potential of recently produced fuel for even higher temperature and burn-up. Irradiating fuel under defined conditions to extremely high burn-ups will provide a better understanding of fission product release and failure mechanisms if particle failure occurs. After an overview of the irradiation rigs used in the HFR, this paper sums up data collected from previous irradiation tests in terms of thermocouple data. Some research and development work for further improvement of thermocouples and other on-line instrumentation will be outlined. (authors)

Study on the cytogenetic activity of freshly irradiated potatoes

International Nuclear Information System (INIS)

Zajtsev, A.N.; Osipova, I.N.

1978-01-01

Cytogenetic activity of potatoes, subjected to gamma irradiation in the dose of 10 Krad, feeding the animals in a day after irradiation, has been investigated. The frequency of chromosomal aberrations in bone marrow cells of mice, who obtained newly irradiated raw or baked potatoes, has no substantial difference from the analogous mutageneity index of mice from the control group. The data obtained are of practical importance when considering the problem of using gamma-irradiated potatoes in the people nourishment

Polarization of electron-beam irradiated LDPE films: contribution to charge generation and transport

Science.gov (United States)

Banda, M. E.; Griseri, V.; Teyssèdre, G.; Le Roy, S.

2018-04-01

Electron-beam irradiation is an alternative way to generate charges in insulating materials, at controlled position and quantity, in order to monitor their behaviour in regard to transport phenomena under the space charge induced electric field or external field applied. In this study, low density polyethylene (LDPE) films were irradiated by a 80 keV electron-beam with a flux of 1 nA cm‑2 during 10 min in an irradiation chamber under vacuum conditions, and were then characterized outside the chamber using three experimental methods. The electrical behaviour of the irradiated material was assessed by space charge measurements using the pulsed electro-acoustic (PEA) method under dc stress. The influence of the applied electric field polarity and amplitude has been tested in order to better understand the charge behaviour after electron-beam irradiation. Fourier transform infra-red spectroscopy (FTIR) and photoluminescence (PL) measurements were performed to evaluate the impact of the electron beam irradiation, i.e. deposited charges and energy, on the chemical structure of the irradiated samples. The present results show that the electrical behaviour in LDPE after irradiation is mostly driven by charges, i.e. by physical process functions of the electric field, and that changes in the chemical structure seems to be mild.

Electron spin resonance intercomparison studies on irradiated foodstuffs

Energy Technology Data Exchange (ETDEWEB)

Raffi, J [CEA Centre d` Etudes de Cadarache, 13 - Saint-Paul-lez-Durance (FR)

1992-07-01

The results of intercomparison studies organized by the Community Bureau of Reference on the use of electron spin resonance spectroscopy for the identification of irradiated food are presented. A qualitative intercomparison was carried out using beef and trout bones, sardine scales, pistachio nut shells, dried grapes and papaya. A quantitative intercomparison involving the use of poultry bones was also organized. There was no difficulty in identifying meat bones, dried grapes and papaya. In the case of fish bones there is a need for further kinetic studies using different fish species. The identification of pistachio nut shells is more complicated and further research is needed prior to the organization of a further intercomparison. Laboratories were able to distinguish between chicken bones irradiated in the range 1 to 3 KGy or 7 to 10 KGy although there was a partial overlap between the results from different laboratories.

Electron spin resonance intercomparison studies on irradiated foodstuffs

International Nuclear Information System (INIS)

Raffi, J.

1992-01-01

The results of intercomparison studies organized by the Community Bureau of Reference on the use of electron spin resonance spectroscopy for the identification of irradiated food are presented. A qualitative intercomparison was carried out using beef and trout bones, sardine scales, pistachio nut shells, dried grapes and papaya. A quantitative intercomparison involving the use of poultry bones was also organized. There was no difficulty in identifying meat bones, dried grapes and papaya. In the case of fish bones there is a need for further kinetic studies using different fish species. The identification of pistachio nut shells is more complicated and further research is needed prior to the organization of a further intercomparison. Laboratories were able to distinguish between chicken bones irradiated in the range 1 to 3 KGy or 7 to 10 KGy although there was a partial overlap between the results from different laboratories

Studies on the preservation of food by gamma irradiation

International Nuclear Information System (INIS)

Kim, S.K.; Umeda, K.

1979-01-01

This work was conducted to investigate the effects of ionizing radiation on the preservation of potato. The Irish Cobbler potato tubers were irradiated at the doses of 7 krad and 15 krad of gamma ray of Co-60 at room temperature. When the potato tubers were stored under various conditions, the freshness and preservability of irradiated potato tubers were remarkably extended by 20, June. The results of this work are summarized as follows: The potato tubers applied with 15 krad of gamma ray were observed freshness without any shrinkage and defects. The potato tubers of control rotted and sprouted completely on 3, March. All tubers of them were cured at 7 0 C and relative humidity of 90% for a month before irradiation and they were treated at 18-20 0 C and RH 80% for 2 weeks after irradiation. They were stored at the above mentioned conditions. Reducing Sugar content of irradiated potato tubers was negligibly changed such as non-irradiated potato tubers along with an extended storage period, when they, as pre-and post-irradiation, were stored at 7 0 C and RH 90%. If they were treated at 18-20 0 C and RH 80% for 2 weeks after irradiation, reducing sugar content of the potato tubers was temporarily increased and then it was decreased as much as the former. As the result of microscopic test for the wound-peridom formation of potato tubers, the dark brown cork layer of wounded tuber of control was perfectly built up at about 2 weeks of the post wound, and starch particles have disappeared almost. The cork layer of irradiated potato tuber was formed at 3-4 weeks after wounded and also starch particles were not watched. The layers irradiated potato was observed the same as cork layer of sound potato. (author)

A study on the composition of off-odor volatiles in irradiated pork

International Nuclear Information System (INIS)

Lin Ruotai; Geng Shengrong; Zhang Jinmu; Chen Yuxia; Liu Yangmin; Wang Liping; Wang Hong; Xu Ying; Yao Side

2006-01-01

The purpose of this study was to lay a foundation on generation mechanisms and removal method of off-odor of irradiated meat products. Vacuum-package and refrigerated raw pork samples were irradiated with 60 Co γ-rays. Off-odor volatiles from the irradiated pork samples were taken in by a vacuum system and were collected by a cooled vial in liquid nitrogen. At the same time, the source of off-odor generation was investigated. Main compositions of off-odor volatiles of the irradiated pork were analyzed with gas chromatograph mass spectrometry (GC-MS). The results showed that main compositions of the off-odor volatiles were dimethyl disulfide, dimethyl sulfide, dimethyl trisulfide, methanethiol and S-methyl thioacetate, and the off-odor volatiles came from sulfide-containing amino acid and thiamin of the irradiated pork. Sulfide-containing compounds increased with the dose in the range of 0-3 kGy, and decreased with the refrigeration time, but changed from different kinds of the package. The non-irradiated samples, however, contained just a little sulfide-containing compounds of dimethyl sulfide and vangardbt. (authors)