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Sample records for external co-60 gamma

  1. Toxoplasma gondii gamma irradiation using Co-60

    International Nuclear Information System (INIS)

    Serra-Freire, Nicolau Maues

    1996-01-01

    The use of nuclear power through radiation for the destruction of microorganisms which cause food deterioration, infections and toxicosis, is specifically for peaceful purposes. Toxoplasma gondii is a protozoa responsible for illnesses in humans and animals. One of the most common ways of transmission is through raw or poorly cooked meat. There is little information on the resistance of T. gondii to radiation. The objective of this research is to determine the Minimum Lethal Dose (MLD) of gamma radiation for those microorganisms. Suspensions of T. gondii containing approximately one million taquizoites/ml were irradiated with doses between up 0,01 up to 0,15 kGy (Kilogray) and inoculated to mice. The surviving T. gondii were re-irradiated with 0,01 up to 0,16 kGy. The irradiated protozoa were totally destroyed with a 0,15 kGy dose (MLD). Taquizoites issued from live protozoa of 0,14 kGy also were completely destroyed with dose of 0,15 kGy. No increase in resistance was observed regarding the non irradiated protozoa. (author)

  2. Co-60 gamma radiation assisted diffusion of iodine in polypropylene

    Energy Technology Data Exchange (ETDEWEB)

    Mathakari, N.L.; Bhoraskar, V.N. [Microtron Accelerator Laboratory, Department of Physics, University of Pune, Pune, Maharashtra 411007 (India); Dhole, S.D., E-mail: sanjay@physics.unipune.ernet.i [Microtron Accelerator Laboratory, Department of Physics, University of Pune, Pune, Maharashtra 411007 (India)

    2010-09-15

    Thin films of polypropylene having dimensions 50 mm x 15 mm x 350 {mu}m were immersed in 1 N iodine solution and then irradiated with Co-60 gamma radiation for the periods of 48, 96 and 144 h at the doses varying from 14.4 to 43.2 kGy. The films were also kept immersed in iodine solution for similar periods but without irradiation. Furthermore, the films were also directly-irradiated with Co-60 gamma radiation for similar periods and doses. The radiation-iodinated, plain-iodinated and directly-irradiated samples were characterized by using various techniques such as weight gain EDS, SEM, FTIR, UV-visible spectroscopy, contact angle and XRD. Weight gain, EDS and SEM collectively reveal that gamma irradiation enhances iodine intake in polypropylene. FTIR, EDS and contact angle measurements indicate that presence of iodine during irradiation resists radiation induced carbonylation of polypropylene. FTIR also shows presence of HOI (Hypoiodous acid) species instead of expected C-I bonds. UV-visible analysis unambiguously shows that presence of iodine enhances radiation induced band gap reduction process of polypropylene. XRD indicates that iodine decreases the crystallinity of polypropylene.

  3. Eradication of sweet potato weevil using Co-60 gamma radiation

    International Nuclear Information System (INIS)

    Tokunaga, Taizo

    2007-01-01

    Sweet potato weevil which is a harmful insect injuring sweet potatoes was found out at Yoron Island in 1915 for the first time in Kagoshima prefecture, Japan. Here the eradication of sweet potato weevils using cobalt 60 irradiation achieved at Kikai Island is described. The mass-reared male weevils in potatoes are in pasture after sterilized by gamma irradiation. If the sexually sterile male copulates with a wild female, the egg does not incubate. By the repeated sterilization during several generations, the eradication of sweet potato weevils was accomplished. (M.H.)

  4. The primary exposure standard for Co-60 gamma radiation: characteristics and measurements procedures

    International Nuclear Information System (INIS)

    Laitano, R.F.; Toni, M.P.

    1983-01-01

    A description is given of a cavity ionization chamber used, as a primary exposure standard, at the Laboratorio di Metrologia delle Radiazioni Ionizzanti of the ENEA in Italy. The primary standard is designed to make absolute measurements of exposure due to the Co-60 gamma radiation. The procedures for the realizationof the exposure unit are also described. Finally results of some international comparisons are reported

  5. Radiosensitivity of California Wonder pepper variety to Co-60 gamma rays

    International Nuclear Information System (INIS)

    Puertas Arias, Ana Leonor; Gonzalez Nunez, Luis Manuel; Ramirez Fernandez, Ramiro

    1998-01-01

    Seeds of California wonder pepper variety were irradiated with dosages among 100-800 Gy, to intervals of 100 Gy, in a source of Co 60 gamma rays, with the objective of determining its radiosensitivity and to establish the adequate interval of dosage for the mutation breeding. A decrease of the growing indicators, productivity and plant fertility was observed with the increasing of irradiation dosages and the interval among 130-460 Gy was established as the most adequate

  6. Effects of CO-60 gamma radiation on the embryonary development of Biomphalaria Glabrata (Say, 1818)

    International Nuclear Information System (INIS)

    Okazaki, K.

    1988-01-01

    Some aspects of the effects of the ionizing radiation on the embryo and on the genetical material of Biomphalaria glabrata (Mollusca: Gastropoda) are presented. The embryos weresubmitted at various stages of development to doses of 5,10,15,20 and 25 Gy of Co-60 gamma radiation. As a criteia of evaluation of the embryos radiosensitivity, four biological parameters were used: mortality, malformation, hatching and chromossomal aberrations. (M.A.C.) [pt

  7. Functionalization and magnetization of carbon nanotubes using Co-60 gamma-ray irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Chen, C.Y.; Fu, M.J.; Tsai, C.Y. [Division of Isotope Application, Institute of Nuclear Energy Research, Atomic Energy Council, P.O. BOX 3-27 Longtan, Taoyuan County 32546, Taiwan (R.O.C.) (China); Lin, F.H. [Institute of Biomedical Engineering, National Taiwan University, No. 1, Sec. 4, Roosevelt Road, Taipei 10617, Taiwan (R.O.C.) (China); Chen, K.Y., E-mail: chenky@iner.gov.tw [Division of Isotope Application, Institute of Nuclear Energy Research, Atomic Energy Council, P.O. BOX 3-27 Longtan, Taoyuan County 32546, Taiwan (R.O.C.) (China)

    2014-10-01

    Functionalized magnetic carbon nanotubes (CNTs) can be used in the biological and biomedical fields as biosensors, drug delivery systems, etc., which makes research into processes for manufacturing modified CNTs quite important. In this paper, Co-60 gamma irradiation is shown to be an effective tool for fabricating functionalized and magnetized CNTs. After the Co-60 gamma irradiation, the presence of carboxylic functional groups on the CNT walls was confirmed by their Fourier transform infrared spectra, and the presence of Fe{sub 3}O{sub 4} was verified by the X-ray diffraction patterns. The functionalized and magnetized CNTs produced using Co-60 gamma irradiation have excellent dispersion properties. The techniques for functionalizing and magnetizing CNTs are introduced in this paper, and applications of the modified CNTs will be reported after more data are gathered. - Highlights: Dispersion ability of carbon nanotubes (CNTs) was improved by functionalization. CNTs were easily manipulated by precipitation of magnetic nanoparticles. Our product can be used as versatile biosensor substrate for biomarker screening.

  8. Effect of Co-60 irradiation on hyperimmune antimeningococcus globulins-gamma

    International Nuclear Information System (INIS)

    Galguera, M.; Le Riverand, E.; Padron, S.

    1990-01-01

    Globulins-gamma from voluntary blood donors immunized with the Cuban BC antimeningococcus vaccine is now being used in our country for the treatment of the meningococcus disease. This study of the effect of Co-60 irradiation on antimeningococcus globulins-gamma was carried out to try to eliminate the inconvenience shown by the traditionally used sterilization procedures (losses in the filter and persistence of viral contamination). globulins-gamma was obtained by ethanol fractionation and was irradiated at a different dose in solution with different stabilizers and it was also lyophilized. Results of the chemical controls carried out lead to the conclusion that it is possible to use radiosterilization on this product in a lyophilized form. The preservation of bactericidal activity, even after the highest irradiation doses, confirms the above mentioned. 13 refs

  9. Gamma radiation (Co60) effects on active substances and microbe burden of medicinal plants

    International Nuclear Information System (INIS)

    Dall'Agnol, L.

    2001-01-01

    In order to evaluate the effects of radioactivity on active vegetal substances, samples of Fennel (Foeniculum vulgare Miller., fructus), Guarana (Paulinia cupana, Kunth, semen), Gingko (gingko biloba, L., folium), and Kawa-Kawa (Piper methysticum G. Forst, rhizoma), were treated with scaling doses (0 to 25 KGy) of gamma radiation (Co 60 ). The 'blind test' methodology was used. The active substances from each sample were analysed by qualitative and quantitative methods after radiation. There were no significant differences seen between the control sample (0 KGy) and the irradiated samples. Microbe contamination was significantly reduced, about 10000 CFU/g, with the initial 5 KGy dose. It was concluded that gamma radiation can be used as an alternative procedure to reduce microbiologic contamination in medicinal plants. Before this procedure can be extended to other medicinal plants, more specific analytical methods are recommended to verify possible structural alterations in active vegetal molecules. (author)

  10. Calculational methods for estimating skin dose from electrons in Co-60 gamma-ray beams

    International Nuclear Information System (INIS)

    Higgins, P.D.; Sibata, C.H.; Attix, F.H.; Paliwal, B.R.

    1983-01-01

    Several methods have been employed to calculate the relative contribution to skin dose due to scattered electrons in Co-60 gamma-ray beams. Either the Klein-Nishina differential scattering probability is employed to determine the number and initial energy of electrons scattered into the direction of a detector, or a Gaussian approximation is used to specify the surface distribution of initial pencil electron beams created by parallel or diverging photon fields. Results of these calculations are compared with experimental data. In addition, that fraction of relative surface dose resulting from photon interactions in air alone is estimated and compared with data extrapolated from measurements at large source-surface distance (SSD). The contribution to surface dose from electrons generated in air is 50% or more of the total skin dose for SSDs greater than 80 cm

  11. Effect of low doses of gamma radiation of Co-60 (radio-hormesis) in tomato seeds

    International Nuclear Information System (INIS)

    Wiendl, Toni Andreas

    2010-01-01

    Tomato seeds of the Gladiador hybrid were exposed to gamma radiation of Co-60 with the following doses: 0; 2,5; 5; 7,5; 10; 12,5; 15 e 20 Gy. Analysis were performed on germination, seedlings height to cotyledon, seedling total height, seedling fresh and dry weight, plant height, stalk diameter at the root beginning, fresh and dry weight of the 5 th leaf, number of green fruits with diameter higher than 3 cm, number of green, half ripen and ripen fruits, total number of fruits, Brix and pH of fruits, average fruit weight and fruit total production. A variety of stimulation effects were observed on the different plant developing stages. The greatest stimulus for production was observed in the 10 Gy dose. The highest seedling average height and plant average height were observed for the 7,5 Gy dose. The biggest number of green fruits with diameter higher than 3 cm occurred for the 12,5 and 15 Gy treatments. Irradiation also stimulated a higher total number of fruits in all doses, having advantage the 10 Gy dose which produced 88% more fruits than control as well as 86% more weight production. The fruits pH acidified significantly in a dose of 12,5 Gy and higher. Production increased in all treatments comparing to control and the highest stimulus for production observed was for the 10, 12,5 and 15 Gy. The use of low gamma radiation doses of Co-60 applied as pre-sowing treatment in the seeds, efficiently stimulated the development of plants and the tomato production. (author)

  12. Mechanical Property Of Zeolite-PVA Composite Mixture Irradiated By Gamma Ray Of Co-60

    International Nuclear Information System (INIS)

    Darsono; Danu, Sugiarto; Las, Tamzil

    2000-01-01

    Experiment on preparation of zeolite-polyvinyl alcohol composite for absorbance materials have been done by curring using Gamma γ-ray of Co-60. Zeolite with the particles size of 60 mesh was mixed with polyvinyl alcohol (PVA) at the concentration of the mixture were 6,9, and 12% by weight, than they were poured into glass tube (length = 100 mm; diameter = 10 mm) and irradiated at the doses of 10, 20, 30 dan 40 kGy with the dose rate of 7,5 kGy/ hr. Parameters observed were density, compressive strength, and hardness. Experimental results showed that polyvinyl alcohol in the mixture was significant effect to density and compressive strength, where as the irradiation dose was highly significant effect to compressive strength. The effect interaction between dose and polyvinyl alcohol concentration factors had significant effect to density or compressive strength. Almost all samples have pencil hardness of 4 - 5 H, for composite containing 6 % PVA, has pencil hardness of 2 - 3 H

  13. Dosimetric properties of dysprosium doped calcium magnesium borate glass subjected to Co-60 gamma ray

    Energy Technology Data Exchange (ETDEWEB)

    Omar, R. S., E-mail: ratnasuffhiyanni@gmail.com; Wagiran, H., E-mail: husin@utm.my; Saeed, M. A. [Department of Physics, Faculty of Science, Universiti Teknologi Malaysia, 81310 Johor Bahru (Malaysia)

    2016-01-22

    Thermoluminescence (TL) dosimetric properties of dysprosium doped calcium magnesium borate (CMB:Dy) glass are presented. This study is deemed to understand the application of calcium as the modifier in magnesium borate glass with the presence of dysprosium as the activator to be performed as TL dosimeter (TLD). The study provides fundamental knowledge of a glass system that may lead to perform new TL glass dosimetry application in future research. Calcium magnesium borate glass systems of (70-y) B{sub 2}O{sub 3} − 20 CaO – 10 MgO-(y) Dy{sub 2}O{sub 3} with 0.05  mol % ≤ y ≤ 0.7  mol % of dyprosium were prepared by melt-quenching technique. The amorphous structure and TL properties of the prepared samples were determined using powder X-ray diffraction (XRD) and TL reader; model Harshaw 4500 respectively. The samples were irradiated to Co-60 gamma source at a dose of 50 Gy. Dosimetric properties such as annealing procedure, time temperature profile (TTP) setting, optimization of Dy{sub 2}O{sub 3} concentration of 0.5 mol % were determined for thermoluminescence dosimeter (TLD) reader used.

  14. Co60 and Cs137 gamma radiation effects on textured bscco Superconducting fibers

    International Nuclear Information System (INIS)

    Leyva Fabelo, A.; Bouza Dominguez, J.; Cruz Inclan, Crlos M.

    2001-01-01

    Bi2Sr2CaCu2Ox superconducting fibers synthesized by solid state reaction and textured by the method of zonal laser ablation were irradiated with gamma rays of 1.25 MeV and 662 keV and studied the behavior of some of its properties with the exposition dose. The measurements of dynamic magnetic susceptibility were used for the characterization of the samples. It was observed that for the dose of up to 600 kGy in the case of the Co60 and until 500 mGy for the Cs137, the fibers preserve its superconducting intragrain properties. It is an evidence of the high resistance of the material to the radiacional damage. In all the cases were verified that with the increase of the dose the Ton of the transition grows. Two possible mechanisms that play the most important role in this effect are explained in the text. The ac measurements allowed to verified the increasing behavior of the superconducting volume fraction in the sample with the exposition dose

  15. Comparison of W-VC-C composites against Co-60, Se-75 and Sb-125 for gamma radioisotope sources

    Science.gov (United States)

    Demir, Ertugrul; Tugrul, A. Beril; Buyuk, Bulent; Yilmaz, Ozan; Ovecoglu, Lutfi

    2018-02-01

    Tungsten based materials are considered to be the promising materials for nuclear applications due to the good properties. The tungsten composite materials have so many advantages in nuclear technological applications especially fusion reactor systems. In this paper, Tungsten-Vanadium carbide-Graphite (W-VC-C) which include 93% tungsten (W), 6% vanadium carbide (VC) and 1% graphite (C) also which has three different alloying time (6-12-24 hours) were produced by mechanical alloying method. Co-60, Se-75 and Sb-125 gamma radioisotopeswere used as a gamma sources in order to determine behavior of gamma attenuation properties of the composite materials. The experimental results were compared with each other to clarify effects of varying gamma energies on the tungsten based composite materials. The mass attenuation coefficients of the samples were obtained by using XCOM computer code and compared with experimental data. The gamma linear attenuation, the mass attenuation coefficients and half value thickness (HVL) of the samples were evaluated and compared with Co-60, Se-75 and Sb-125 for gamma radioisotopes. Results showed that gamma attenuation coefficients of the samples depend on gamma energies and mechanical alloying time has negatively effect on the gamma shielding properties for the all studied W-VC-C.

  16. Assessment of shielding integrity of Co-60 gamma irradiation-ray scanner at Aflao Border, Ghana

    International Nuclear Information System (INIS)

    Agbemafo, Edwin Capacity

    2016-07-01

    This study examines the current state of the shielding integrity of the 38.7 TBq Co-60 gamma ray scanner with an average energy of 1.25 MeV operated by NICK TC Scan Limited, which has been in use for destination inspection at Aflao Border of Ghana, for the past six years, (2010-2016). The facility uses a high energy ionizing radiation in its operation; therefore continuous adequacy of the installed biological shielding is critical to the protection and safety of the workers and the general public. The workload of the facility has increased since its commissioning, requiring the review of the status of the installed shielding. Theoretical calculations for dose rates and barrier thicknesses based on tenth – value layer (TVL) concept and NCRP 151, 2005 recommendations, were done around the scanning facility using the current operational data. The results were then compared with the measured dose rates and the shielding thickness constituted during the commissioning stage, and international standards. Calculated dose rate at commissioning state ranges from 0.6μSv/hr to 2.4μSv/hr with an average dose rate of 1.43μSv/hr and that of the current operational state ranges from 1.1μSv/hr to 2.6μSv/hr with an average dose rate of 1.54μSv/hr, indicating an increase of 7.9%. Even though the dose rates were all below the recommended dose limit of 20μSvh"-"1 by NCRP, there has been an increase in dose to the staff and the general public. It has been observed that, the workload has increased three-fold from the commissioning stage to current operational state over the past six years. The assessment done on the installed shielding using the current operational data indicates that the shielding is inadequate in providing protection for the general public and the workers against X-ray radiation source of energy of at least 6MeV, and therefore the facility in its current state cannot be used to house a linear accelerator of energy up to 10MeV. (au)

  17. The effects of Co60 gamma rays on the absorption of salicylic natrium orally given to white rats

    International Nuclear Information System (INIS)

    Wiharto, Kunto; Kamal, Zainul; Mulyanto; Muryono, H.

    1982-01-01

    The effects of Co 60 gamma rays on the absorption of salicylic natrium orally taken by white rats after being irradiated were studied. Patients treated with radiation used to be given analgesic drugs to elicit pain. Effects of radiation on the physiology of gastrointestinal tracts of such patients are to be studied. Based on this perception some white rats were irradiated with Co 60 gamma rays at the cumulative doses of 500, 750, and 1000 rads which were fractionated to 5 daily doses of 100, 150, and 200 rads. Salicylate concentration in the rat's blood was measured with spectrophotometer. It was found that the greater the radiation dose was given, the less salicylic natrium was absorbed and at a certain dose saturation point happened. (RUW)

  18. Measurement of Cerenkov Radiation Induced by the Gamma-Rays of Co-60 Therapy Units Using Wavelength Shifting Fiber

    Directory of Open Access Journals (Sweden)

    Kyoung Won Jang

    2014-04-01

    Full Text Available In this study, a wavelength shifting fiber that shifts ultra-violet and blue light to green light was employed as a sensor probe of a fiber-optic Cerenkov radiation sensor. In order to characterize Cerenkov radiation generated in the developed wavelength shifting fiber and a plastic optical fiber, spectra and intensities of Cerenkov radiation were measured with a spectrometer. The spectral peaks of light outputs from the wavelength shifting fiber and the plastic optical fiber were measured at wavelengths of 500 and 510 nm, respectively, and the intensity of transmitted light output of the wavelength shifting fiber was 22.2 times higher than that of the plastic optical fiber. Also, electron fluxes and total energy depositions of gamma-ray beams generated from a Co-60 therapy unit were calculated according to water depths using the Monte Carlo N-particle transport code. The relationship between the fluxes of electrons over the Cerenkov threshold energy and the energy depositions of gamma-ray beams from the Co-60 unit is a near-identity function. Finally, percentage depth doses for the gamma-ray beams were obtained using the fiber-optic Cerenkov radiation sensor, and the results were compared with those obtained by an ionization chamber. The average dose difference between the results of the fiber-optic Cerenkov radiation sensor and those of the ionization chamber was about 2.09%.

  19. Load of Co-60 in large gamma irradiators: a safe proceeding

    International Nuclear Information System (INIS)

    Luca, Gilmara C.; Paquer, Daniela

    2011-01-01

    The inclusion of new Co-60 sources in industrial irradiators is an extra procedure to its operation and extremely critical. The operation requires planning, attention, responsibility and a well trained staff. Radiation level, package contamination and radioactive material escape evaluations are essential as measurement of pre-loading safety. The package transfer for the swimming pool i e the most critical moment of the operation. After sources transfer to the racks, it is necessary the monitoring of tools, package and sources through the scrubbing test. Notwithstanding to be a critical operation, the risk is minimized when it is performed according to safe rules and radiation protection, and in the process performed the individual accumulated doses does not exceed 50 to μSv

  20. Calculational methods for estimating skin dose from electrons in Co-60 gamma-ray beams

    International Nuclear Information System (INIS)

    Higgins, P.D.; Sibata, C.H.; Attix, F.H.; Paliwal, B.R.

    1983-01-01

    Several methods have been employed to calculate the relative contribution to skin dose due to scattered electrons in Co-60 γ-ray beams. Either the Klein--Nishina differential scattering probability is employed to determine the number and initial energy of electrons scattered into the direction of a detector, or a Gaussian approximation is used to specify the surface distribution of initial pencil electron beams created by parallel or diverging photon fields. Results of these calculations are compared with experimental data. In addition, that fraction of relative surface dose resulting from photon interactions in air alone is estimated and compared with data extrapolated from measurements at large source--surface distance (SSD). The contribution to surface dose from electrons generated in air is 50% or more of the total skin dose for SSDs greater than 80 cm

  1. Load of Co-60 in large gamma irradiators: a safe proceeding; Carregamento de Co-60 em irradiadores de grande porte: um procedimento seguro

    Energy Technology Data Exchange (ETDEWEB)

    Luca, Gilmara C.; Paquer, Daniela, E-mail: gilmara@cbesa.com.b, E-mail: daniela@cbesa.com.b [CBE Embrarad, Jarinu, SP (Brazil)

    2011-10-26

    The inclusion of new Co-60 sources in industrial irradiators is an extra procedure to its operation and extremely critical. The operation requires planning, attention, responsibility and a well trained staff. Radiation level, package contamination and radioactive material escape evaluations are essential as measurement of pre-loading safety. The package transfer for the swimming pool i e the most critical moment of the operation. After sources transfer to the racks, it is necessary the monitoring of tools, package and sources through the scrubbing test. Notwithstanding to be a critical operation, the risk is minimized when it is performed according to safe rules and radiation protection, and in the process performed the individual accumulated doses does not exceed 50 to {mu}Sv

  2. Synthesis of gold nano particles with enlargement size by gamma Co-60 irradiation and investigation of anti oxidation effect

    International Nuclear Information System (INIS)

    Nguyen Ngoc Duy; Dang Van Phu; Le Anh Quoc; Nguyen Quoc Hien

    2014-01-01

    Gold nanoparticles (AuNPs) with size in the range of 10-53 nm were synthesized by gamma Co-60 irradiation using water-soluble chitosan (WSC) as stabilizer and size enlargement by seed approach. Absorption wavelength (λ max ) was measured by UV-Vis spectroscopy and particle size was determined from TEM images. Results showed that value of λ max increased from 523 nm (seed particles) to 525, 537 and 549 nm and the size of AuNPs increased from 10 nm (seed particles) to 20, 38 and 53 nm, respectively, for concentration ratio of Au 3+ /Au 0 (seed) of 2.5, 5 and 10. Antioxidant effect of AuNPs with size of 10, 20, 38 and 53 nm was investigated using free radical 2, 2'-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid) (ABTS .+ ). Results indicated that the smaller the particle size was (10 nm) the stronger the antioxidant effect attained. Thus, AuNPs/WSC synthesis by gamma Co-60 irradiation are promising for applications as antioxidants in cosmetics and in other fields as well. (author)

  3. PERUBAHAN KARAKTER KUANTITATIF MUCUNA PRURIENS GENERASI M1 PASCA IRRADIASI SINAR GAMMA CO-60

    Directory of Open Access Journals (Sweden)

    Yustinus Ulung Anggraito

    2015-02-01

    Full Text Available Koro benguk (Mucuna pruriens berpotensi sebagai bahan substitusi kedelai. Keragaman genetik koro benguk termasuk kategori rendah, sehingga perlu ditingkatkan keragaman genetiknya terutama pada faktor-faktor produksi. Tujuan penelitian adalah mendapatkan informasi mutasi mikro pada koro benguk generasi M1 setelah diradiasi dengan sinar gamma dari Cobalt-60. Benih koro benguk diperoleh dari Balai Pengembangan Perbenihan Tanaman Pangan dan Hortikultura (BP2TPH Ngipiksari, Sleman, Yogyakarta. Radiasi sinar gamma dilakukan di PAIR BATAN Pasar Jumat, Jakarta. Dosis radiasi gamma yang digunakan adalah 0; 25 Gy, 50 Gy; 100 Gy; 150 Gy, 200 Gy, dan 250 Gy. Eksperimen dilakukan menggunakan Rancangan Acak Kelompok (RAK. Parameter yang diamati adalah umur berbunga, jumlah polong, jumlah biji, berat 100 biji tanaman generasi M1. Data dianalisis menggunakan Anava, dilanjutkan dengan Uji Beda Nyata Duncan (DMRT. Hasil penelitian menunjukkan bahwa peningkatan dosis radiasi sinar gamma akan memperpanjang hari munculnya bunga dan berat biji, namun menurunkan jumlah polong dan jumlah biji pada tanaman generasi M1.

  4. Electrophysical properties of In P crystals, irradiated with CO-60 gamma quanta

    International Nuclear Information System (INIS)

    Aliyev, M.I.; Guseynova, M.A.; Aliyev, I.M.; Ragimov, S.S.

    2005-01-01

    Full text : n-InP monocrystals were investigated before and after gamma irradiation having a doze about 10 and also within temperature interval from 77 to 320 K. On χ(T) and σ(T) dependences it is revealed that during gamma irradiation p-type antistructural defects are generated in n-InP crystals. It gives an opportunity of receiving of not alloyed semiinsulating indium fosfide [ru

  5. Effects of gamma Co-60 radiation on the growth and development of peppermint (Mentha arvensis L.)

    International Nuclear Information System (INIS)

    Tran Thi Le Minh; Nguyen Truong Giang; Bui Thi Hong Gam; Le Quang Luan

    2015-01-01

    In this study, mints were regenerated from calluses irradiated by γ-rays (Co-60) at doses from 0 to 70 Gy. After 4 times of propagation, the M_1V_4 mints were transferred in a greenhouse for assessments of growth, development and essential oil content. Mint regenerated from calluses irradiated at low doses (0, 3, 4, 6, 8 and 10 Gy) showed no morphological difference compared to the control plants. However, low-dose irradiated mints showed better effect on growth and development, and mints regenerated from 6 Gy-irradiated sample had essential oil content with 1.3 times higher than that of control group. In case of plants irradiated at higher dose (30, 40, 50, 60 and 70 Gy), there were morphological variations such as stem become bigger and color of stem become purple. Especially, samples irradiated at 60 Gy showed better in growth, development and essential oil content (1.34 times higher than the control plants) and these characters were stable in M_1V_4. Among the irradiated mints, purple stem variations had the highest essential oil yield with 1.7 times higher than that of the original plants. (author)

  6. Study On In Vitro Variation Generation Of Cymbidium Labell Anna Belle By Gamma Co-60 Irradiation

    International Nuclear Information System (INIS)

    Nguyen Huynh Phuong Uyen; Vo Thi Thu Ha; Le Quang Luan

    2011-01-01

    Radiation ionization is one of useful methods for mutation breeding of plants. In this study, γ-ray (Co-60) was used for generating morphological variations of Cymbidium Labell Anna Belle. The lethal doses of 50% samples (LD 50 ) after 4 months cultivation were determined at 35.0 Gy for protocorm like bodies (PLBs), 37.4 Gy for in vitro shoot bubs and 70.1 Gy for plantlets. PLBs were found as suitable samples for generation of variation of mentioned Cymbidium. The dose range from 20 to 50 Gy was determined with a high ability of variation on C. Labell Anna Belle. The highest frequency of variation was obtained ca. 3.82 x 10 -3 at the dose of 30 Gy. 157 in vitro variant plantlets were selected in M 1 V 1 generation, among variations, the variations were mainly found with 5 following types: removal of chlorophyll (8 plantlets), the leaves become shorter (64 plantlets), the leaves become longer (64 plantlets), increase of leaf number (11 plantlets) and the colour of pericardium was changed from green into violet (10 plantlets). Twenty one variant lines were selected in M 1 V 2 generation. (author)

  7. Desulfurization of petroleum by Co-60 gamma irradiation and analysis of products using GC-MS

    International Nuclear Information System (INIS)

    Mathuthu, M.; Tshivhase, V.M.; Olobatoke, R.Y.; Gaxela, N.N.

    2014-01-01

    Sulfur is an undesirable hetero-atom that has negative on motor engines if present in quantities between 50 and 180.000 ppm. Research has shown that sour petroleum can be 'sweetened' by gamma irradiation to de-sulfurize the crude oil. In this research we will report experimental results of desulfurizing petroleum locally procured. The objective is to improve the quality of product delivered to the motor market and also reduce the environmental pollution due to SO 2 emissions from engines. The gamma irradiated (de-sulfurized petroleum was chemically analyzed using GC-MS. The preliminary results show that the petroleum is polymerized by gamma radiation to higher molecular mass. The un-irradiated petroleum had a sulfur concentration of 3.24% and 0.020% wt after gamma irradiation. The sulfur content was reduced by a factor of about 160 when dose was increased from zero to 50 kGys. GC-MS Chromatographs are presented for the identified hydrocarbons after gamma irradiation. (authors)

  8. Reliability studies on Si PIN photodiodes under Co-60 gamma radiation

    Energy Technology Data Exchange (ETDEWEB)

    Prabhakara Rao, Y. P. [Integrated Circuits Division, Bharat Electronics Limited, Bangalore, Karnataka-560013 (India) and Department of Studies in Physics, University of Mysore, Manasagangotri, Mysore, Karnataka-570006 (India); Praveen, K. C.; Gnana Prakash, A. P. [Department of Studies in Physics, University of Mysore, Manasagangotri, Mysore, Karnataka-570006 (India); Rani, Y. Rejeena [Integrated Circuits Division, Bharat Electronics Limited, Bangalore, Karnataka-560013 (India)

    2013-02-05

    Silicon PIN photodiodes were fabricated with 250 nm SiO{sub 2} antireflective coating (ARC). The changes in the electrical characteristics, capacitance-voltage characteristics and spectral response after gamma irradiation are systematically studied to estimate the radiation tolerance up to 10 Mrad. The different characteristics studied in this investigation demonstrate that Si PIN photodiodes are suitable for high radiation environment.

  9. Calibration curve to establish the exposure dose at Co60 gamma radiation

    International Nuclear Information System (INIS)

    Guerrero C, C.; Brena V, M.

    2000-01-01

    The biological dosimetry is an adequate method for the dose determination in cases of overexposure to ionizing radiation or doubt of the dose obtained by physical methods. It is based in the aberrations analysis produced in the chromosomes. The behavior of leisure in chromosomes is of dose-response type and it has been generated curves in distinct laboratories. Next is presented the curve for gamma radiation produced in the National Institute of Nuclear Research (ININ) laboratory. (Author)

  10. Effects of Co60 gamma radiation on the immunogenic and antigenic properties of Bothrops jararacussu venom

    International Nuclear Information System (INIS)

    Spencer, Patrick J.; Nascimento, Nanci do; Rogero, Jose R.

    1997-01-01

    Ionizing radiation has been successfully employed to attenuate animals toxins and venoms for immunizing antisera producing animals. However, the radiation effects on antigenicity and immunogenecity have not yet been elucidated. In the present work, we investigated the effects of gamma rays on the antigenic and immunogenicity have not yet been elucidated. In the present work, we investigated the effects of gamma rays on the antigenic and immunogenic behaviour of Bothrops jararacussu venon. Venom samples (2mg/ml in 150 mM NaCl) were irradiated with 500, 1000 and 2000 Gy of 60 Co gamma rays. These samples were submitted to antigen capture ELISA on plates coated with commercial bothropic antiserum. Results suggest a loss of reactivity of the 1000 and 2000 Gy irradiated samples. Antibodies against native and 2000 Gy irradiated venoms were produced in rabbits. Both sera able to bind native venom with a slightly higher titer for anti-irradiated serum. These data suggest that radiation promoted structural modification on the antigen molecules. However since the antibodies produced against irradiated antivenom were able to recognize native venom, there must have been preservation of some antigenic determinants. It has already been demosntrated that irradiation of proteins leads to structural modifications and unfolding of the molecules. Our data suggest that irradiation led to conformational epitopes destruction with preservation of linear epitopes and that the response against irradiated venom may be attributed to these linear antigenic determinants. (author). 8 refs., 3 figs

  11. Biochemical and pharmacological studies of native and irradiated crotamine with gamma radiation of Co60

    International Nuclear Information System (INIS)

    Mitake, M.B.

    2000-01-01

    Ionizing radiation can change the molecular structure and affect the biological properties of biomolecules. This has been employed to attenuate animal toxins. Crotamine is a strongly basic polypeptide from South American rattlesnake venom, composed of 42 amino acid residues. It induces skeletal muscle spasms, leading to a spastic paralysis of hind limbs in mice. The objective was to carry out biochemical and pharmacological studies of native and irradiated crotamine with Co. Crotamine was purified from Crotalus durissus terrificus venom by Sephadex G-100 gel filtration followed by ion exchange chromatography, using a Fast performance Liquid Chromatography (FPLC) system. It was irradiated at 2 mg/ml in 0.15 m NaCl with 2.0 kGy gamma radiation emitted by a Co source. Native and irradiated crotamine were evaluated by biochemical characterization, toxic activity (LD50), and biodistribution. The native and irradiated crotamine were labeled with 29.6 MBq of I using chloramine T method and separated in a Sephadex G-50 column. Male Swiss mice (35 @ 5 g) were injected IP with 0.1 mL (2.4x10 cpm/mouse) of I native crotamine or with 0.4 mL (1.3 x 10 cpm/mouse) of I irradiated crotamine. The animals were sacrificed by ether inhalation at 0.08, 0.25, 0.5,1, 2, 3, 4, 8, 12, and 24 hours. Blood, spleen, liver, kidneys, brain, lungs, heart, and skeletal muscle were collected in order to determine radioactivity content. The results showed that gamma radiation did not change protein concentration, electrophoretic profile, or protein primary structure, although differences could be seen by spectroscopic techniques. Gamma radiation reduced crotamine toxicity, but did not eliminate bioactivity. Biodistribution studies showed that native and irradiated crotamine have hepatic metabolism and renal elimination. Native and irradiated crotamine have an affinity to skeletal muscle and did not cross the blood-brain barrier. (author)

  12. Profitability of an Co 60 semi-industrial irradiator type Gamma Beam 651 Pt

    International Nuclear Information System (INIS)

    Cruz Z, E.

    1997-01-01

    It is described the capacity in volume of processed material by irradiation interesting interesting for the industry and how many laboratory samples can be processed. It is showed the costs of the annual processing, that is, the relation between the volume of sterilized material and his cost, this give us an idea about the profits for this type of gamma irradiators designed for low capacity, where is necessary to define the effective area of sterilization using high dose dosimetry. Also have been compared the maintenance costs, operation and salaries including monetary devaluation in function of the real production of the irradiation processing. Finally, it is remarked the objectives and essential characteristics of this semi-industrial irradiator. (Author)

  13. Effects of Co60 gamma radiation on Biomphalaria glabrata (Say, 1818) Embryo. II. Malformations

    International Nuclear Information System (INIS)

    Okazaki, K.; Kawano, T.

    1990-01-01

    The morphogenetic effects of ionizing radiation were investigated in Biomphalaria glabrata embryos irradiated in the cleavage, blastula, gastrula, young trochophore and trochophore stages with 5 to 25 Gy doses of 60 CO gamma radiation. The number of malformed embryos rapidly increased with increasing radiation dose, reaching a maximum between 5th to 8th day after irradiation in all stages analyzed. Susceptibility to malformation induction was higher the younger than the age of the irradiated embryo. However, for the cleavage stage the frequency of malformed embryos was inversely proportional to radiation dose for the same radiation dose. Several types of morphogenetic malformations were obtained, among then cephalic malformations, exogastrula, shell malformations and embryos with everted stomodeum, unspecific malformations being the most frequent. The results show that the types of malformation induced by radiation probably are not radiation-specific and do not depend on the dose applied [pt

  14. Comparative nephrotoxicity of native or Co-60 gamma rays irradiated crotoxin in mice

    Energy Technology Data Exchange (ETDEWEB)

    Rocha, Andre Moreira; Alves, Glaucie J.; Aires, Raquel da Silva; Turibio, Thompson O.; Thomazi, Gabriela O. Coelho; Spencer, Patrick J.; Nascimento, Nanci do, E-mail: andrerocha@usp.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Nascimento-Rocha, Josefa M.; Magalhaes Filho, Asterio Souza, E-mail: 0304@prof.itpacporto.com.br [Instituto Tocantinense Presidente Antonio Carlos Porto (ITPAC), Porto Nacional, TO (Brazil)

    2015-07-01

    Snake venoms are complex mixtures of proteins and peptides with a wide spectrum of physiological targets such as the blood coagulation and cardiovascular systems and the motor end plate among others. Acute renal failure is a common complication in accidents with the South American rattlesnake. The toxin involved in this pathology is the crotoxin, a major component of the venom in terms of concentration and toxicity. Snake venoms, when irradiated with {sup 60}Co gamma rays present a significant decrease in toxicity while the immunogenic properties of its components are preserved. The use of irradiated venom is an attractive alternative for antisera production since it might reduce the appearance of renal lesions improving the welfare and lifespan of those animals employed on antivenom production. At the present work, we have compared the effects of native and irradiated crotoxin on the mice renal function. Tubular lesions were observed in all the samples from the animal group injected with native crotoxin. Animals injected with the irradiated toxin presented alteration only after 30 minutes and 1 hour after injection. These data suggest that the onset of the renal lesions is delayed and that the severity of the lesions might be lower when using irradiated crotoxin. (author)

  15. DOSKMF2, Dose Rate Distribution in Co60 Gamma Irradiation Plants

    International Nuclear Information System (INIS)

    Remer, M.

    1988-01-01

    1 - Description of program or function: The DOSKMF2 code calculates dose rate distributions in gamma irradiation facilities with 60 Co sources. It has been developed as a tool for the evaluation of research units for the characterization, modification and optimization as well as for the simulation, planning design and evaluation of pilot and industrial facilities. 2 - Method of solution: The basic model of DOSKMF2 contains the computation of the exposure rate, which is dependent on a system of radiation sources (line and/or point sources) at one point of the radiation field. The geometric conditions are described by two coordinate systems. The first is used to arrange the radiation sources and tubes; the second is used to describe the shielding layers in the form of concentric circles. The build-up factor is approximated by Taylor coefficients, also in the case of multi-layer configurations. Calculations of radiation fields in complex irradiation facilities are made by many organizational variants based on the basic model. The interpretation of the results is supported by some statistical calculations. It is possible to store the calculated dose rate values for further processing. 3 - Restrictions on the complexity of the problem: The DOSKMF2 code is presently limited to 40 irradiation tubes and 10 crossed shielding layers. This can be increased by changing dimension statements and input organization

  16. Comparative nephrotoxicity of native or Co-60 gamma rays irradiated crotoxin in mice

    International Nuclear Information System (INIS)

    Rocha, Andre Moreira; Alves, Glaucie J.; Aires, Raquel da Silva; Turibio, Thompson O.; Thomazi, Gabriela O. Coelho; Spencer, Patrick J.; Nascimento, Nanci do; Nascimento-Rocha, Josefa M.; Magalhaes Filho, Asterio Souza

    2015-01-01

    Snake venoms are complex mixtures of proteins and peptides with a wide spectrum of physiological targets such as the blood coagulation and cardiovascular systems and the motor end plate among others. Acute renal failure is a common complication in accidents with the South American rattlesnake. The toxin involved in this pathology is the crotoxin, a major component of the venom in terms of concentration and toxicity. Snake venoms, when irradiated with 60 Co gamma rays present a significant decrease in toxicity while the immunogenic properties of its components are preserved. The use of irradiated venom is an attractive alternative for antisera production since it might reduce the appearance of renal lesions improving the welfare and lifespan of those animals employed on antivenom production. At the present work, we have compared the effects of native and irradiated crotoxin on the mice renal function. Tubular lesions were observed in all the samples from the animal group injected with native crotoxin. Animals injected with the irradiated toxin presented alteration only after 30 minutes and 1 hour after injection. These data suggest that the onset of the renal lesions is delayed and that the severity of the lesions might be lower when using irradiated crotoxin. (author)

  17. Effect of low doses of gamma radiation of Co-60 (radio-hormesis) in tomato seeds; Efeitos de baixas doses de radiacao gama do Co-60 (radio-hormesis) em sementes de tomate

    Energy Technology Data Exchange (ETDEWEB)

    Wiendl, Toni Andreas

    2010-07-01

    Tomato seeds of the Gladiador hybrid were exposed to gamma radiation of Co-60 with the following doses: 0; 2,5; 5; 7,5; 10; 12,5; 15 e 20 Gy. Analysis were performed on germination, seedlings height to cotyledon, seedling total height, seedling fresh and dry weight, plant height, stalk diameter at the root beginning, fresh and dry weight of the 5{sup th} leaf, number of green fruits with diameter higher than 3 cm, number of green, half ripen and ripen fruits, total number of fruits, Brix and pH of fruits, average fruit weight and fruit total production. A variety of stimulation effects were observed on the different plant developing stages. The greatest stimulus for production was observed in the 10 Gy dose. The highest seedling average height and plant average height were observed for the 7,5 Gy dose. The biggest number of green fruits with diameter higher than 3 cm occurred for the 12,5 and 15 Gy treatments. Irradiation also stimulated a higher total number of fruits in all doses, having advantage the 10 Gy dose which produced 88% more fruits than control as well as 86% more weight production. The fruits pH acidified significantly in a dose of 12,5 Gy and higher. Production increased in all treatments comparing to control and the highest stimulus for production observed was for the 10, 12,5 and 15 Gy. The use of low gamma radiation doses of Co-60 applied as pre-sowing treatment in the seeds, efficiently stimulated the development of plants and the tomato production. (author)

  18. A comparison of 4 MeV Proton and Co-60 gamma irradiation induced degradation in the electrical characteristics of N-channel MOSFETs

    Energy Technology Data Exchange (ETDEWEB)

    Anjum, Arshiya; Vinayakprasanna, N.H.; Pradeep, T.M. [Department of Studies in Physics, University of Mysore, Manasagangotri, Mysore 570006 (India); Pushpa, N. [Department of PG Studies in Physics, JSS College, Ooty Road, Mysore 570025 (India); Krishna, J.B.M. [IUC-DAE CSR, Kolkota 700098 (India); Gnana Prakash, A.P., E-mail: gnanaprakash@physics.uni-mysore.ac.in [Department of Studies in Physics, University of Mysore, Manasagangotri, Mysore 570006 (India)

    2016-07-15

    N-channel depletion MOSFETs were irradiated with 4 MeV Proton and Co-60 gamma radiation in the dose range of 100 krad(Si) to 100 Mrad(Si). The electrical characteristics of MOSFET such as threshold voltage (V{sub th}), density of interface trapped charges (ΔN{sub it}), density of oxide trapped charges (ΔN{sub ot}), transconductance (g{sub m}), mobility (μ), leakage current (I{sub L}) and drain saturation current (I{sub D} {sub Sat}) were studied as a function of dose. A considerable increase in ΔN{sub it} and ΔN{sub ot} and decrease in V{sub th,}g{sub m}, μ, and I{sub D} {sub Sat} was observed after irradiation. The results of 4 MeV Proton irradiation were compared with that of Co-60 gamma radiation and it is found that the degradation is more for the devices irradiated with 4 MeV Protons when compared with the Co-60 gamma radiation. This indicates that Protons induce more trapped charges in the field oxide region when compared to the gamma radiation.

  19. Total integrated dose testing of solid-state scientific CD4011, CD4013, and CD4060 devices by irradiation with CO-60 gamma rays

    Science.gov (United States)

    Dantas, A. R. V.; Gauthier, M. K.; Coss, J. R.

    1985-01-01

    The total integrated dose response of three CMOS devices manufactured by Solid State Scientific has been measured using CO-60 gamma rays. Key parameter measurements were made and compared for each device type. The data show that the CD4011, CD4013, and CD4060 produced by this manufacturers should not be used in any environments where radiation levels might exceed 1,000 rad(Si).

  20. Evaluación no destructiva de la patogenicidad de Cercospora agavicola en vitroplántulas de agave azul tequilero irradiadas con rayos gamma Co60

    OpenAIRE

    Ángeles-Espino, A.; Virgen-Calleros, G.; Valencia-Botín, J.; Ramírez-Serrano, C.; Paredes-Gutiérrez, L.; Hurtado-De la Peña, S.

    2016-01-01

    Resumen: El cultivo del agave y el tequila tienen importancia económica y social por los empleos en campo y la industria, además por las divisas de la exportación. El tizón foliar causado por Cercospora agavicola representa un alto riesgo en la zona de Los Altos de Jalisco, debido a que el clima favorece la dispersión y germinación de las esporas. Se inocularon plántulas obtenidas a partir de yemas axilares, mismas que se irradiaron con rayos gamma Co60 a 0 Gy (testigo), 5 Gy, 10 Gy, 15 Gy, 2...

  1. Evaluation through comet assay of DNA damage induced in human lymphocytes by alpha particles. Comparison with protons and Co-60 gamma rays

    International Nuclear Information System (INIS)

    Di Giorgio, M.; Kreiner, A. J.; Schuff, J. A.; Vallerga, M. B.; Taja, M. R.; Lopez, F. O.; Alvarez, D. E.; Saint Martin, G.; Burton, A.; Debray, M. E.; Kesque, J. M.; Somacal, H.; Stoliar, P.; Valda, A.; Davidson, J.; Davidson, M.; Ozafran, M. J.; Vazquez, M. E.

    2004-01-01

    Several techniques with different sensitivity to single-strand breaks and/or double strand breaks were applied to detect DNA breaks generated by high LET particles. Tests that assess DNA damage in single cells might be the appropriate tool to estimate damage induced by particles, facilitating the assessment of heterogeneity of damage in a cell population. The microgel electrophoresis (comet) assay is a sensitive method for measuring DNA damage in single cells. The objective of this work was to evaluate the proficiency of comet assay to assess the effect of high LET radiation on peripheral blood lymphocytes, compared to protons and Co-60 gamma rays. Materials and methods: Irradiations of blood samples were performed at TANDAR laboratory (Argentina). Thin samples of human peripheral blood were irradiated with different doses (0-2.5 Gy) of 20.2 MeV helium-4 particles in the track segment mode, at nearly constant LET. Data obtained were compared with the effect induced by a MeV protons and Co-60 gamma rays. Alkaline comet assay was applied. Comets were quantified by the Olive tail moment. Distribution of the helium-4 particle and protons were evaluated considering Poisson distribution in lymphocyte nuclei. The mean dose per nucleus per particle result 0.053 Gy for protons and 0.178 Gy for helium-4 particles. When cells are exposed to a dose of 0.1 Gy, the hit probability model predicts that 43% of the nuclei should have experienced and alpha traversal while with protons, 85% of the nuclei should be hit. The experimental results show a biphasic response for helium-4 particles (0.1 Gy), indicating the existence of two subpopulations: unhit and hit. Distributions of tail moment as a function of fluence and experimental dose for comets induced by helium-4 particles, protons and Co-60 gamma rays were analyzed. With helium-4 irradiations, lymphocyte nuclei show an Olive tail moment distribution flattened to higher tail moments a dose increase. However, for irradiations with

  2. Effect of Co-60 gamma radiation on optical, dielectric and mechanical properties of strontium L-ascorbate hexahydrate NLO crystal

    Science.gov (United States)

    Dileep, M. S.; Suresh Kumar, H. M.

    2018-04-01

    A potentially useful nonlinear optical semi-organic single crystal of strontium L-ascorbate hexahydrate (SLAH) was grown by solution growth slow evaporation technique at room temperature. The grown crystal is semi transparent, yellowish in color with monoclinic crystal system having space group P21 and is stable up to 198 °C. Further, SLAH crystals were irradiated with gamma rays produced by 60Co with different doses of 10 KGy, 30 KGy and 50 KGy at room temperature and then studied the effect of gamma-rays on dielectric properties, optical absorption, microhardness and SHG efficiency. The absorption study reveals that the absorbance of the grown crystal is appeared to be low throughout the visible region with a lower cutoff wavelength of 277 nm and these parameters are not affected upon gamma irradiation. The luminescence intensity of the crystal is also not affected by the irradiation. There is noticeable changes were observed in dielectric properties and hardness of the materials for different doses of gamma irradiation. The second harmonic generation (SHG) efficiency of the grown crystal is 0.54 times that of the KDP crystal and is decreased moderately by increasing the dosage of gamma irradiation.

  3. Radiation inactivation of Paenibacillus larvae and sterilization of American Foul Brood (AFB) infected hives using Co-60 gamma rays

    Energy Technology Data Exchange (ETDEWEB)

    De Guzman, Zenaida M. [Microbiological Research and Service Laboratory, Atomic Research Division, Philippine Nuclear Research Institute, Diliman, Quezon City (Philippines); Cervancia, Cleofas R. [Institute of Biological Sciences, College of Arts and Sciences, University of the Philippines, Los Banos, Laguna (Philippines); Dimasuay, Kris Genelyn B.; Tolentino, Mitos M.; Abrera, Gina B.; Cobar, Ma. Lucia C. [Microbiological Research and Service Laboratory, Atomic Research Division, Philippine Nuclear Research Institute, Diliman, Quezon City (Philippines); Fajardo, Alejandro C.; Sabino, Noel G.; Manila-Fajardo, Analinda C. [Institute of Biological Sciences, College of Arts and Sciences, University of the Philippines, Los Banos, Laguna (Philippines); Feliciano, Chitho P., E-mail: cpfeliciano@pnri.dost.gov.ph [Microbiological Research and Service Laboratory, Atomic Research Division, Philippine Nuclear Research Institute, Diliman, Quezon City (Philippines); Institute of Biology, College of Science, University of the Philippines, Diliman, Quezon City (Philippines)

    2011-10-15

    The effectiveness of gamma radiation in inactivating the Philippine isolate of Paenibacillus larvae was investigated. Spores of P. larvae were irradiated at incremental doses (0.1, 0.2, 0.4, 0.8 and 1.6 kGy) of gamma radiation emitted by a {sup 60}Co source. Surviving spores were counted and used to estimate the decimal reduction (D{sub 10}) value. A dose of 0.2 kGy was sufficient to inactivate 90% of the total recoverable spores from an initial count of 10{sup 5}-9x10{sup 3} spores per glass plate. The sterilizing effect of high doses of gamma radiation on the spores of P. larvae in infected hives was determined. In this study, a minimum dose (D{sub min}) of 15 kGy was tested. Beehives with sub-clinical infections of AFB were irradiated and examined for sterility. All the materials were found to be free of P. larvae indicating its susceptibility to {gamma}-rays. After irradiation, there were no visible changes in the physical appearance of the hives' body, wax and frames. Thus, a dose of 15 kGy is effective enough for sterilization of AFB-infected materials. - Highlights: > We characterized Paenibacillus larvae and determined its radiation sensitivity. > We investigated the effectiveness of gamma rays in inactivating P. larvae. > Gamma radiation inactivates P. larvae. > 15 kGy is effective for the sterilization of P. larvae-infected hives. > Irradiation produces no visible changes in the hives' body, waxes and frames.

  4. Radiation inactivation of Paenibacillus larvae and sterilization of American Foul Brood (AFB) infected hives using Co-60 gamma rays

    International Nuclear Information System (INIS)

    De Guzman, Zenaida M.; Cervancia, Cleofas R.; Dimasuay, Kris Genelyn B.; Tolentino, Mitos M.; Abrera, Gina B.; Cobar, Ma. Lucia C.; Fajardo, Alejandro C.; Sabino, Noel G.; Manila-Fajardo, Analinda C.; Feliciano, Chitho P.

    2011-01-01

    The effectiveness of gamma radiation in inactivating the Philippine isolate of Paenibacillus larvae was investigated. Spores of P. larvae were irradiated at incremental doses (0.1, 0.2, 0.4, 0.8 and 1.6 kGy) of gamma radiation emitted by a 60 Co source. Surviving spores were counted and used to estimate the decimal reduction (D 10 ) value. A dose of 0.2 kGy was sufficient to inactivate 90% of the total recoverable spores from an initial count of 10 5 -9x10 3 spores per glass plate. The sterilizing effect of high doses of gamma radiation on the spores of P. larvae in infected hives was determined. In this study, a minimum dose (D min ) of 15 kGy was tested. Beehives with sub-clinical infections of AFB were irradiated and examined for sterility. All the materials were found to be free of P. larvae indicating its susceptibility to γ-rays. After irradiation, there were no visible changes in the physical appearance of the hives' body, wax and frames. Thus, a dose of 15 kGy is effective enough for sterilization of AFB-infected materials. - Highlights: → We characterized Paenibacillus larvae and determined its radiation sensitivity. → We investigated the effectiveness of gamma rays in inactivating P. larvae. → Gamma radiation inactivates P. larvae. → 15 kGy is effective for the sterilization of P. larvae-infected hives. → Irradiation produces no visible changes in the hives' body, waxes and frames.

  5. Effect of gamma radiation (Co60) in physic-chemical and sensory properties of aged beans (Phaseolus vulgaris, L.)

    International Nuclear Information System (INIS)

    Nascimento, Lenice Magali do

    1992-01-01

    The objective of this work is to evaluate the efficiency of different doses of gamma radiation as an alternative process to improve the quality of aged beans. Beans of the 'Carioca 80' variety were submitted to an accelerated aging process according to the followings patterns: 30 deg C and 50 or 75% relative humidity and 40 deg C and 50 or 80% relative humidity, during 45 days. After that time samples were submitted to gamma irradiation at doses of 300, 600, 900 and 1200 Krad. At the same time samples of 1989, 1987 and 1983 harvest and submitted to slow aging process, 12 deg C and 50-60% relative humidity, were evaluated to comparison with former accelerated aging. All the samples were analysed on moisture and starch content, cooking time, texture and sensorial evaluation. The results showed that samples submitted to aged faster presented better quality, second the evaluated parameters, as far as irradiation applied was 300 Krad. The same happened to samples of harvest 1989 aged slowly. The 1987 and 1983 harvests, respectively, were the doses that gave better softness to the beans. This work permitted conclude that gamma irradiation is an alternative method of advantage for aged beans, for same decrease the cooking time and improvement the sensory quality of stored grain. (author)

  6. Stromal damage in the mouse small intestine after Co60 gamma or D-T neutron irradiation

    International Nuclear Information System (INIS)

    Carr, K.E.; Hamlet, R.; Nias, A.H.; Boyle, F.C.; Fife, M.G.

    1985-01-01

    Stromal constituents have been examined in mouse small intestine 3 1/2 days after irradiation with either 18-20 Gy gamma rays or 10 Gy neutrons. These doses were chosen for their equivalent effect on the number of intestinal crypts found after treatment. Despite the fact that the topography of the villi, as imaged by scanning electron microscopy, was altered by treatment, with gamma irradiated villi showing lateral or horizontal collapse while neutron irradiation produced conical villi, few changes were seen in the villous stromal compartments. There were, however, ultrastructural changes observed in the stroma of the pericryptal plate. Changes common to both radiation schedules included disorganisation of the subepithelial stroma and an increase in the number of irregular processes. Some changes after irradiation, however, were not identical in the two groups. Gamma irradiation resulted in pale, foamy cytoplasmic vesicles, the separation of smooth muscle cells and changes in the structure of the luminal aspect of arterial blood vessels while neutron irradiation produced dense cytoplasmic vesicles and electron dense bodies within the substance of peripheral nerve twigs. The fact that the variation in the topography of villi after the two types of radiation is matched by changes in the deep stroma rather than within the villi themselves indicates that the stromal pericryptal plate is of importance in the structure of the villus and the extent to which the villi have varied from the normal finger shaped structure

  7. Modifications of structural, chemical, and electrical characteristics of Er2O3/Si interface under Co-60 gamma irradiation

    Science.gov (United States)

    Kaya, Senol; Yilmaz, Ercan

    2018-03-01

    This paper reports the influences of gamma radiation on the structural, electrical, and chemical characteristics of erbium oxide (Er2O3) thin films and the possible mechanisms underlying these irradiation-induced effects. The crystallographic and morphological modifications under gamma irradiation were characterized by X-ray diffraction (XRD) and atomic force microscopy (AFM), respectively, while radiation influences on electrochemical characteristics were analyzed by X-ray photoelectron spectroscopy (XPS). Furthermore, changes in electrical characteristics were analyzed on the basis of capacitance-voltage (C-V) and conductance-voltage (G/ω-V) measurements. The XRD results demonstrated that small atomic displacement was observed and that the grain size of the nanostructure slightly increased. Improvements in surface roughness were observed in AFM measurements. The observed variations in the XRD and AFM measurements can be attributed to the radiation-induced local heating and microscopic atomic mobility. In addition, the XPS analysis obviously demonstrated that the oxygen vacancies increased with irradiation dose because of the breaking of Er2O3 and ErxOy bonds. Significant influences of the generated oxygen vacancies on the electrical measurements were observed, and the radiation-induced hole traps, which caused large flat band shifts, can be attributed to the generated oxygen vacancies. The results show that radiation does not degrade the physical characteristics significantly, but the generation of oxygen vacancies considerably increases the electrical sensitivity of the Er2O3 dielectric.

  8. Effect of Co-60 gamma irradiated chitosan and phosphorus fertilizer on growth, yield and trigonelline content of Trigonella foenum-graecum L.

    Directory of Open Access Journals (Sweden)

    Tariq Ahmad Dar

    2015-07-01

    Full Text Available Natural marine polysaccharides such as chitosan, sodium alginate and carrageenan; after depolymerization by different techniques, have shown promising plant growth promoting and other biological activities. Chitosan after irradiation with Co-60 gamma-rays have proven to be a miraculous plant growth promoter in different plants. Trigonelline; an anti-diabetic compound is obtained mainly from the seeds of Fenugreek (Trigonella foenum-graecum L.. Trigonelline counteracts diabetes mellitus (DM through the operation of the mechanisms of insulin secretion, modulation of β-cell regeneration and stimulation of activity of glucose metabolism related enzymes. Considering the medicinal importance a pot experiment was conducted to investigate the effect of foliar application of Co-60 gamma irradiated chitosan (IC with soil applied phosphorus supplement on growth, biochemical and quality attributes of fenugreek. Four concentrations of irradiated chitosan were used (0, 40, 80 and 120 mg L−1 individually as well as in combination with single dose of phosphorus 40 kg ha−1. Un-irradiated chitosan (UN 40 mg L−1 and de-ionized water were used as control. IC significantly affected almost all the parameters including seed yield, trigonelline content and trigonelline yield. There were 10 treatments and among all, P40 + IC 40 mg L−1 proved to be the best, which increased total alkaloid content by 34.9%, seed yield by 125.4%, and trigonelline content by 17.8%. Contents of photosynthetic pigments and activity of nitrate reductase, carbonic anhydrase enzymes were also significantly enhanced.

  9. The relative biological effectiveness (RBE) of high-energy electrons, x-rays and Co-60 gamma-rays

    International Nuclear Information System (INIS)

    Kiyono, Kunihiro

    1974-01-01

    Linac (Mitsubishi-Shimizu 15 MeV medical linear accelerator) electron beams with actual generated energies of 8, 10, 12 and 15 MeV were compared with X-ray beams having energies of 8 and 10 MV. The RBE values were calculated from 50 percent hatch-ability (LD 50 ) in silk-worm embryos, 30-days lethality (LDsub(50/30)) in ddY mice, and mean lethal dose (Do) in cultured mouse YL cells or human FL cells. To estimate the RBE in clinical experiments, LRD (leukocyte reduction dose) value was calculated for each patient irradiated on the chest or lumbar vertebrae. It was concluded that there is little difference in practical significance between 8 to 10 MV X-rays and 8 to 15 MeV electrons, and that the biological effects of Linac radiations are about 90 to 100 percent of the effect of 60 Co gamma rays. The RBE values gradually decreased, contrary to the elevation of energy between 8 and 15 MeV for electrons and between 8 and 10 MV for X-rays. These values were compared with those of earlier reviews of work in this field, and were briefly discussed. (Evans, J.)

  10. C-188 Co-60 sources installation and source rack loading optimization processes in a gamma irradiation facility

    Energy Technology Data Exchange (ETDEWEB)

    Santos, Paulo de S.; Vasquez, Pablo A.S., E-mail: psantos@ipen.br, E-mail: pavsalva@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2017-11-01

    Since 2004, the Multipurpose Gamma Facility at the Nuclear and Energy Research Institute has been providing services on radiation processing for disinfection and sterilization of health care and disposable medical products as well to support research studies on modification of physical, chemical and biological properties of several materials. Recently, there was an increment in irradiation of the Cultural Heritages. This facility uses C-188 double-encapsulated radioactive Cobalt-60 sources known as pencils from manufactures outside of country. The activity of the cobalt sources decays into a stable nickel isotope with a half-life around 5.27 years, which means a loss of 12.3% annually. Then, additional pencils of Cobalt-60 are added periodically to the source rack to maintain the required capacity or installed activity of the facility. The manufacturer makes shipping of the radioactive sources inside a high density container type B(U) , by sea. This one involves many administrative, transport and radiation safety procedures. Once in the facility, the container is opened inside a deep pool water to remove the pencils. The required source geometry of the facility is obtained by loading these source pencils into predetermined diagram or positions in source modules and distributing these modules over the source rack of the facility. The dose variation can be reduced placing the higher activity source pencils near the periphery of the source rack. In this work are presented the procedures for perform the boiling leaching tests applied to the container, the Cobalt-60 sources installation, the loading processes and the source rack loading optimization. (author)

  11. The Co-60 gamma-ray irradiation effects on the Al/HfSiO4/p-Si/Al MOS capacitors

    Science.gov (United States)

    Lok, R.; Kaya, S.; Karacali, H.; Yilmaz, E.

    2017-12-01

    In this work, the initial interface trap density (Nit) to examine device compability for microelectronics and then the Co-60 gamma irradiation responses of Al/HfSiO4/p-Si/Al (MOS) capacitors were investigated in various dose ranges up to 70 Gy. Pre-irradiation response of the devices was evaluated from high frequency (HF) and low frequency (LF) capacitance method and the Nit was calculated as 9.91 × 1011 cm-2 which shows that the HfSiO4/p-Si interface quality is convenient for microelectronics applications. The irradiation responses of the devices were carried out from flat-band and mid-gap voltage shifts obtained from stretch of capacitance characteristics prior to and after irradiation. The results show that the flat band voltages very slightly shifted to positive voltage values demonstrating the enhancement of negative charge trapping in device structure. The sensitivity of the Al/HfSiO4/p-Si/Al MOS capacitors was found to be 4.41 mV/Gy for 300 nm-thick HfSiO4 gate dielectrics. This value approximately 6.5 times smaller compared to the same thickness conventional SiO2 based MOS devices. Therefore, HfSiO4 exhibits crucial irradiation tolerance in gamma irradiation environment. Consequently, HfSiO4 dielectrics may have significant usage for microelectronic technology as a radiation hard material where radiation field exists such as in space applications.

  12. Multistep carcinogenesis of normal human fibroblasts. Human fibroblasts immortalized by repeated treatment with Co-60 gamma rays were transformed into tumorigenic cells with Ha-ras oncogenes.

    Science.gov (United States)

    Namba, M; Nishitani, K; Fukushima, F; Kimoto, T

    1988-01-01

    Two normal mortal human fibroblast cell strains were transformed into immortal cell lines, SUSM-1 and KMST-6, by treatment with 4-nitroquinoline 1-oxide (4NQO) and Co-60 gamma rays, respectively. These immortalized cell lines showed morphological changes of cells and remarkable chromosome aberrations, but neither of them grew in soft agar or formed tumors in nude mice. The immortal cell line, KMST-6, was then converted into neoplastic cells by treatment with Harvey murine sarcoma virus (Ha-MSV) or the c-Ha-ras oncogene derived from a human lung carcinoma. These neoplastically transformed cells acquired anchorage-independent growth potential and developed tumors when transplanted into nude mice. All the tumors grew progressively without regression until the animals died of tumors. In addition, the tumors were transplantable into other nude mice. Normal human fibroblasts, on the other hand, were not transformed into either immortal or tumorigenic cells by treatment with Ha-MSV or c-Ha-ras alone. Our present data indicate that (1) the chemical carcinogen, 4NQO, or gamma rays worked as an initiator of carcinogenesis in normal human cells, giving rise to immortality, and (2) the ras gene played a role in the progression of the immortally transformed cells to more malignant cells showing anchorage-independent growth and tumorigenicity. In other words, the immortalization process of human cells seems to be a pivotal or rate-limiting step in the carcinogenesis of human cells.

  13. Dosis óptima de irradiación gamma con Co60 para inducción de mutagénesis en pastos

    Directory of Open Access Journals (Sweden)

    Alan Álvarez-Holguín

    2017-01-01

    Full Text Available La dosis letal (DL 50 y reducción media del crecimiento (RC 50 son parámetros utilizados para seleccionar dosis de irradiación adecuadas e inducir mutaciones para realizar mejoramiento genético vegetal. El objetivo fue determinar la DL 50 y RC 50 para conocer la dosis ó p tima de irradiación c on Co 60 en semilla de pasto llorón, buffel, banderita y navajita. Se evaluaron seis dosis de irradiación con Co 60 en semilla : 100, 200, 300, 450, 600 y 900 Gray (Gy y un tratamiento control (T - 0, sin irradiación. Las variables evaluadas fueron : porcentaj e de germinación (%GE, índice de velocidad de germinación (IVG, longitud de plúmula (LP y longitud de radícula (LR. Se realizó análisis de regresión y comparación de medias con la prueba de Dunnett. Mediante la ecuación de regresión se estimó la DL 50 p ara el %GE, así como RC 50 para el resto de las variables. La DL 50 se ponderó con 55%, mientras que la RC 50 se ponderó en 15% para cada una de las tres variables restantes. En general, los valores de las variables disminuyeron (P<0.05 conforme se incremen tó la dosis de irradiación, lo cual permitió determinar la DL 50 y RC 50 para cada especie. La media ponderada se obtuvo a los 628 Gy, 712 Gy, 698 Gy y 411 Gy para pasto llorón, buffel, banderita y navajita, respectivamente. Se recomiendan las dosis plantead as en este estudio, ya que esto permitirá plantear las bases para realizar mejoramiento genético a través de mutagénesis con irradiación gamma en los pastos evaluados.

  14. Re-evaluation of structural shielding designs of X-ray and CO-60 gamma-ray scanners at the Port of Tema, Ghana

    International Nuclear Information System (INIS)

    Ofori, K.

    2011-07-01

    This research work was conducted to re-evaluate the shielding designs of the 6 MeV x-ray and the 1.253 MeV Co-60 gamma ray scanners used for cargo-containerized scanning at the Port of Tema. These scanners utilize ionizing radiation, therefore adequate shielding must be provided to reduce the radiation exposure of persons in and around the facilities to acceptable levels. The purpose of radiation shielding is to protect workers and the general public from the harmful effects of ionizing radiation. Investigations on the facilities indicated that after commissioning, no work had been carried out to re-evaluate the shielding designs. However, workloads have increased over time neccessitating review of the installed shielding. There has been introduction of scanner units with higher radiation energy (as in the case of the x-ray scanner) posibily increasing dose rates at various location requiring review of the shielding. New structures have been dotted around the facilities without particular attention to their distances and locations with respect to the radiation source. Measurements of distances from the source axes to the points of concern for primary and leakage barrier shielding; source to container and container to the points of concern for scattered radiation shielding were taken. The primary and secondary thicknesses required for both scanners were determined based on current operational parameters and compared with the thickness constituted during the construction of the facilities. Calculated and measured dose rate beyond the shielding barriers were used to established the adequacy or otherwise of the shielding employed by the shielding designers. Values obtained fell below the 20 µSv/hr specified by NCRP 151 (2005) which showed that the primary and secondary shields of both facilities were adequate requiring no additional shielding. (author)

  15. Methodology for solving the problem of contamination in pencils of Co-60 from the CNEA (Argentine) for the recharge of the gamma irradiator of the ININ

    International Nuclear Information System (INIS)

    Villarreal B, J.E.; Escobar A, L.; Angeles C, A.; Cruz G, H.S.

    1992-07-01

    Presently report the methodology used to identify the source of contamination detected in a shipment with 5.0 X 10 Bq of Co-60 coming from Argentina is described, as well as the solution outlined to solve the problem. Its are presented by way of conclusion the experiences but outstanding learned in the process. (Author)

  16. Acción protectora de la melatonina sobre células mononucleares de sangre periférica humana sometidas a radiación gamma Co60

    Directory of Open Access Journals (Sweden)

    Martha Mesa-Villanueva

    2009-04-01

    Full Text Available Protective action of melatonin on human peripheral blood mononuclear cells exposed to gamma radiation Co60. Objective: toevaluate the protective effect of melatonin on peripheral blood mononuclear cells (PBMCs exposed in vitro to ionizing radiation. Materialsand methods: PBMCs drawn from healthy volunteers were incubated with 0, 1x10-5, 1x10-6 y 1x10-7 M melatonin for 10 minutes beforebeing exposed to gamma radiation (300 cGy; Co60 source. Afterwards, DNA damage was evaluated with the comet assay. Results:PBMCs pretreated with melatonin showed comet tails shorter than those without the hormone treatment, as well as a lower percentage ofcells with severe DNA damage. Conclusion: melatonin doses of 1x10-5, 1x10-6 and 1x10-7 M provide in vitro protection to PBMCs fromDNA damage (single strand breaks and alkali-labile sites induced by gamma radiation (300 cGy; Co60 source.

  17. Methodology for solving the problem of contamination in pencils of Co-60 from the CNEA (Argentine) for the recharge of the gamma irradiator of the ININ; Metodologia para resolver el problema de contaminacion en lapices de Co-60 procedentes del CONEA (Argentina) para la recarga del irradiador gamma del ININ

    Energy Technology Data Exchange (ETDEWEB)

    Villarreal B, J.E.; Escobar A, L.; Angeles C, A.; Cruz G, H.S

    1992-07-15

    Presently report the methodology used to identify the source of contamination detected in a shipment with 5.0 X 10 Bq of Co-60 coming from Argentina is described, as well as the solution outlined to solve the problem. Its are presented by way of conclusion the experiences but outstanding learned in the process. (Author)

  18. Disinfestation of export oranges and tangerines (Citrus spp) against medfly Ceratitis capitata (Wied., 1824) (Diptera; Tephritidae) by gamma irradiation (Co-60)

    International Nuclear Information System (INIS)

    Costa, N.

    1990-01-01

    A gamma bean 650 cobalt-60 source was utilized for irradiation (0; 10; 50; 100; 200; 300; 400; 500; 750 and 1000 Gy) of fresh ripe fruits artificially interested by immature stages of Ceratitis capitata to determine the sterilizing and lethal doses. The sensorial and chemical analyses did not show any significant differences between the control and irradiated samples. Differences on loss of weight of oranges show that 500 and 1000 Gy doses were responsible for increasing the loss of water content. (author)

  19. Use of gamma radiation (Co60) as quarentenary treatment, to control the moth Opogona sacchari (Bojer, 1856) (Lepidoptera: Tineidade) on banana (Musa sp.) and Dracaena fragans

    International Nuclear Information System (INIS)

    Potenza, Marcos Roberto

    1999-01-01

    This research had the aim at evaluating the physical treatment by gamma radiation as an alternative method to disinfestate bananas and Dracaena fragans stalks without roots, to exportation, infested with the moth Opogona sacchari. The moth rearing was initiated from infested D. fragans originated from Juquia, state of Sao Paulo. Gammacell 220 with Cobalt-60 with activity of 537, 82 Ci was used as an irradiator. Tests on artificial diet, bananas variety Nanicao and D. fragans stalks without roots were done, with doses varying form 5,0 to 500,0 Gy. The doses of of 140,0; 240,0 and 450,0 Gy fitted the rules of absence of adults emergency, affecting eggs with seven days old, twenty two days old larvae and eleven days old pupae, irradiated on artificial diet, respectively. The dose to disinfestate twenty two days old O. sacchari infesting D. fragans stalk sheaves without roots and bananas in bunch, used to exportation, was 300,0 Gy and to eleven days old pupae, in the some conditions, was of 450,0 Gy. The dose of gamma radiation from 50,0 to 500,0 Gy affected sprouting. (author)

  20. A comparison of three materials used in ESR dosimetry: L-α-alanine, DL-α-alanine and standard bone powder. Response to Co-60 gamma radiation

    International Nuclear Information System (INIS)

    Stuglik, Z.; Sadlo, J.

    1995-01-01

    Three solid state materials: L-α-alanine, DL-α-alanine and standard bone powder were irradiated with gamma analyzed with ESR method. It was stated that the G-value of paramagnetic centres in L-α-alanine is practically the same as in DL-alpha-alanine and about 50 times higher than in non-deproteinized bone powder. The sensitivities of investigated materials are proportional to their G-values if double integrals of ESR signals are chosen as a measure of radiation effects. When first derivatives of ESR absorption bands are used to the construction of dose-response curves (peak-to-peak method) the sensitivities of all investigated materials are comparable. (author). 14 refs, 1 fig., 3 tabs

  1. Enhancement of the immunity and body weight gain in broiler by feeding with the brewer yeast β-glucan degraded by gamma Co-60 radiation

    International Nuclear Information System (INIS)

    Le Quang Luan; Nguyen Thanh Long

    2015-01-01

    The insoluble β-glucan extracted from the cell wall of brewer’s yeast was dispersed in deionized water for swelling, then irradiated in order to degrade into water-soluble β-glucan. The results revealed that the water-soluble β-glucan contents in the irradiated samples were increased with radiation dose to 25.89, 49.07 and 66.71%; whereas their molecular weight (Mw) decreased to 48.1, 23.0 and 10.8 kDa by gamma irradiation at 100, 200 and 300 kGy, respectively. The supplementation of poultry feed with the radiation degraded β-glucan enhanced both non-specific (total white blood cells, lymphocytes, neutrocytes) and specific immune components (anti-Newcastle disease, antiGumboro disease virus and anti-infectious bronchitis virus antibodies) in the broilers. In comparison with the control, broiler fed normal poultry foodstuff without β-glucan, the supplementation of radiation degraded β-glucan not only increased the survival rate of the testing broiler about 33.3% and their average body weight of about 24.4%, but also reduced the feed conversion rate from 4.8 to 3.1 kg. The β-glucan oligosaccharides that having Mw of about 25 kDa produced by gamma irradiation at 200 kGy showed the highest effect on the growth performance and immunomodulatory capability in the immune system of the testing broilers. This product is promising to be applied for production of the safe stimulator of immunity for broiler chickens. (author)

  2. AIRGAMMA, External Gamma-Ray Exposure from Radioactive Cloud

    International Nuclear Information System (INIS)

    Hidaka, Akihide; Iijima, Tshinori

    1989-01-01

    1 - Description of program or function: AIRGAMMA calculates quickly the external exposure to gamma rays from a radioactive cloud. 2 - Method of solution: The external exposure is calculated by interpolating the normalized doses providing on the basis of the Gaussian plume model. 3 - Restrictions on the complexity of the problem: Memory requirement is 30 Kbytes

  3. Experience of the accomplishment of dismantling of a radiation gamma facility with Co-60 source; Experiencia de la realizacion de un cierre definitivo de una instalacion de irradiacion gamma con fuente de {sup 60} Co

    Energy Technology Data Exchange (ETDEWEB)

    Perez Reyes, Yolanda; Hernandez Alvarez, Ramon; Sarabia Molina, Igor I.; Jerez Vegueria, Pablo [Centro Nacional de Seguridad Nuclear, La Habana (Cuba)

    2001-07-01

    The present work describes the experience obtained by the specialists of the Cuban Regulatory Authority, as a result of the evaluation of observance, criteria of security and radiological safety, during the stage conducted in the works of dismantling of a gamma irradiator.

  4. Radiography of Co-60 in the lead cube castings

    International Nuclear Information System (INIS)

    Djoli Soembogo; Harun Al Rasyid R; Namad Sianta

    2016-01-01

    Radiography Co-60 on Carbon steel or Stainless steel has been widely applied, but for metal Lead has not yet been applied and has not yet widely known. Lead has a greater density than Carbon steel or Stainless steel and could muffle gamma radiation so it takes a longer exposure time. The result of its film radiography are also not as good as compared to radiography applications on carbon steel or Stainless steel. The study also applied digital radiography using isotope Co-60 sources and used Epson V700 scanner positive film for digitization results of conventional radiographic films. These radiographs using film AGFA D7 to get the contrast medium, medium sensitivity and good image quality. The purpose of radiography Co-60 on the cube castings Lead is to find indications of defective castings cube Lead and digitizing the results using conventional radiographic film with a positive film media scanner to process the data transfer and storage of digital data. Radiographic testing has been carried out using the isotope Co-60 on metal castings Lead with a single thickness of a single shadow method using positive film scanner media and isotope Co-60 with disabilities observation parameter Lead metal castings on radiographic film. Co-60 radiation time exposure is 3,500 hours for the thickness of the metal cube castings Lead 100 mm with the activity of 29 Ci and perpendicular SFD of 840 mm. Radiographic testing on metal cube castings Lead by the method of a single thickness of single image defects produce a parameter indicative for a cube of metal castings Lead of porosity level 2. The density mean of radiographic film was 2.051 and 2.046 for 5 minutes in a developer solution. The result of scanning positive film is in the form of digital radiography which allows for the transfer of digital data or computerized storage of digital data. This status is still within limits acceptable under the standards referred. (author)

  5. Profitability of an Co 60 semi-industrial irradiator type Gamma Beam 651 Pt; Rentabilidad de un irradiador de Cobalto 60 semi-industrial tipo Gamma beam 651 Pt

    Energy Technology Data Exchange (ETDEWEB)

    Cruz Z, E. [Instituto de Ciencias Nucleares, Universidad Nacional Autonoma de Mexico. Apdo. Postal 70-51, 04510 Mexico D.F. (Mexico)

    1997-12-31

    It is described the capacity in volume of processed material by irradiation interesting interesting for the industry and how many laboratory samples can be processed. It is showed the costs of the annual processing, that is, the relation between the volume of sterilized material and his cost, this give us an idea about the profits for this type of gamma irradiators designed for low capacity, where is necessary to define the effective area of sterilization using high dose dosimetry. Also have been compared the maintenance costs, operation and salaries including monetary devaluation in function of the real production of the irradiation processing. Finally, it is remarked the objectives and essential characteristics of this semi-industrial irradiator. (Author)

  6. Quality assurance and accuracy in Co-60 radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Scarlat, F; Rebigan, F

    1995-12-01

    The characteristics of a set of 88 Co-60 sources ONCOBALT, are described. This set of radioactive sources is an original choice of a variety of cobalt sources in point of physical size and activity. It includes 5 activity groups of cells (stainless steel) among 2 and 12 mCi, 5 and 15 mm active length and 2, 2.5 and 3 mm external diameter, 4 activity groups of needle activities between 1.3 and 3.4 mCi, 15 and 20 mm active length, 1.8 mm external diameter. By an appropriate choice of activities, dimensions and geometry of irradiation we can get an error of max.5% as to the receive dose. The radioactive purity of cobalt is 99.9%. To meet the requirements in practical radiotherapy we checked the Co-60 sources by tests: tight test, mechanical test, corrosion test and contamination test that gave us full satisfaction.

  7. Historical estimates of external gamma exposure and collective external gamma exposure from testing at the Nevada Test Site. I. Test series through HARDTACK II, 1958

    Energy Technology Data Exchange (ETDEWEB)

    Anspaugh, L.R.; Church, B.W.

    1985-12-01

    In 1959, the Test Manager's Committee to Establish Fallout Doses calculated estimated external gamma exposure at populated locations based upon measurements of external gamma-exposure rate. Using these calculations and estimates of population, we have tabulated the collective estimated external gamma exposures for communities within established fallout patterns. The total collective estimated external gamma exposure is 85,000 person-R. The greatest collective exposures occurred in three general areas: Saint George, Utah; Ely, Nevada; and Las Vegas, Nevada. Three events, HARRY (May 19, 1953), BEE (March 22, 1955), and SMOKY (August 31, 1957), accounted for over half of the total collective estimated external gamma exposure. The bases of the calculational models for external gamma exposure of ''infinite exposure,'' ''estimated exposure,'' and ''one year effective biological exposure'' are explained. 4 figs., 7 tabs.

  8. Historical estimates of external gamma exposure and collective external gamma exposure from testing at the Nevada Test Site. I. Test series through HARDTACK II, 1958

    International Nuclear Information System (INIS)

    Anspaugh, L.R.; Church, B.W.

    1986-01-01

    In 1959, the Test Manager's Committee to Establish Fallout Doses calculated estimated external gamma exposure at populated locations based upon measurements of external gamma-exposure rate. Using these calculations and estimates of population, we have tabulated the collective estimated external gamma exposures for communities within established fallout patterns. The total collective estimated external gamma exposure is 85,000 person-R. The greatest collective exposures occurred in three general areas: Saint George, UT; Ely, NV; and Las Vegas, NV. Three events, HARRY (19 May 1953), BEE (22 March 1955), and SMOKY (31 August 1957), accounted for more than half the total collective estimated external gamma exposure. The bases of the calculational models for external gamma exposure of infinite exposure, estimated exposure, and 1-yr effective biological exposure are explained

  9. Historical estimates of external gamma exposure and collective external gamma exposure from testing at the Nevada Test Site. I. Test series through HARDTACK II, 1958

    International Nuclear Information System (INIS)

    Anspaugh, L.R.; Church, B.W.

    1985-12-01

    In 1959, the Test Manager's Committee to Establish Fallout Doses calculated estimated external gamma exposure at populated locations based upon measurements of external gamma-exposure rate. Using these calculations and estimates of population, we have tabulated the collective estimated external gamma exposures for communities within established fallout patterns. The total collective estimated external gamma exposure is 85,000 person-R. The greatest collective exposures occurred in three general areas: Saint George, Utah; Ely, Nevada; and Las Vegas, Nevada. Three events, HARRY (May 19, 1953), BEE (March 22, 1955), and SMOKY (August 31, 1957), accounted for over half of the total collective estimated external gamma exposure. The bases of the calculational models for external gamma exposure of ''infinite exposure,'' ''estimated exposure,'' and ''one year effective biological exposure'' are explained. 4 figs., 7 tabs

  10. Shielding of the GERDA experiment against external gamma background

    International Nuclear Information System (INIS)

    Barabanov, I.; Bezrukov, L.; Demidova, E.; Gurentsov, V.; Kianovsky, S.; Knoepfle, K.T.; Kornouhkov, V.; Schwingenheuer, B.; Vasenko, A.

    2009-01-01

    The GERmanium Detector Array (GERDA) experiment will search for neutrinoless double beta decay of 76 Ge and is currently under construction at the INFN Laboratori Nazionali del Gran Sasso (LNGS) in Italy. The basic design of GERDA is the use of cryogenic liquid and water of high purity as a superior shield against the hitherto dominant background from external gamma radiation. In this paper we show by Monte Carlo simulations and analytical calculations how GERDA was designed to suppress this background at Q ββ ( 76 Ge)=2039keV to a level of about 10 -4 cts/(keVkgy).

  11. Contribution of External Gamma Rays to SPND at HANARO

    Energy Technology Data Exchange (ETDEWEB)

    Park, B. G.; Cho, D. K.; Kim, M. S.; Kang, G. D. [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2014-05-15

    Self-Powered Neutron Detectors (SPNDs) have been widely used for monitoring the neutron flux in reactors as well as in irradiation facilities. In its simplest form, the detector operates on the basis of directly measuring the beta decay current following neutron capture. The neutron capture cross-section of {sup 103}Rh, which is used for an emitter of the SPND, is 142.13 barns for thermal neutron (0.0253 eV). After neuron capture of {sup 103}Rh, the compound nuclei of {sup 104}Rh (92.6%) and {sup 104}mRh (7.4%) are produced. The sensitivity of SPND is generally defined as. The influence of water in the irradiation basket on the external gamma rays is determined by calculations of neutron capture reaction and photon interaction rates at various irradiation positions in HANARO. Since it is not easy to correct the contribution of the external gamma rays to the current signal by measurements at the research reactor, it is advantageous to reduce materials such as water at the irradiation position.

  12. External gamma radiation survey for oil wellheads in Saudi Arabia

    International Nuclear Information System (INIS)

    Nassar, Rafat M.; Mously, Khalid A.; Cowie, Michael I.

    2008-01-01

    Naturally occurring radioactive material (NORM) is known to be associated with oil and gas extraction. As part of a comprehensive NORM management strategy, Saudi Aramco needed to determine the extent of NORM contamination associated with their oil and gas operations. As part of that strategy, this study focused on external gamma survey of oil producing wellheads at various locations. The study aimed to: 1-) Identify wellheads with elevated gamma radiation dose rate; 2-) Specify the exact locations of the high dose rates on the wellheads; 3-) Identify the radioisotopes responsible for the high dose rates; and 4-) Propose worker protection requirements during maintenance. The majority (∼92%) of the surveyed wellheads showed no enhanced gamma dose-rate above background level. From the remaining ∼8%, only a few wellheads showed dose rates between 1,000-3,700 n Sv/h. The study revealed that NORM contamination tends to accumulate at turns of the pipes, around pipe diameter changes, the joints, the back of valves, and at the base of the wellhead. Also, for a given location, NORM build up on the interior of pipework varies over time and continues to migrate down stream until it reaches the Gas and Oil Separation Plants (GOSP). There NORM is expected to accumulate and reside in the form of sludge. Gamma spectroscopy analysis revealed that 226 Ra and its progeny are responsible for the high radiation dose rates detected. It was concluded that NORM will not pose significant radiation hazards to workers as long as the tubing and piping are not opened. (author)

  13. Determination of dose factors for external gamma radiation in dwellings

    International Nuclear Information System (INIS)

    Maduar, M.F.; Hiromoto, G.

    2000-01-01

    A significant contribution to the global population exposure to ionizing radiation arises from natural sources, especially from radionuclides present in terrestrial crust. Human activities can eventually increase that exposure to significant levels, from the point of view of radiological protection. The presence of natural radionuclides in building materials may lead to an increment of both external and internal radiation exposure of the population. External exposure in dwellings arises from gamma-emitter radionuclides existing in the walls, floor and ceiling of their rooms. Mathematical models can be used to predict external dose rates inside the room, known the radionuclide concentration activities in dwelling constituents. This paper presents a methodology for theoretical evaluation of external gamma doses due to radionuclides present in the walls of an hypothetical standard room. The room is modeled as three pairs of rectangular sheets with finite thickness. Assessment of doses was performed through the application of photon transport model, taking in account self-absorption and radiation buildup. As the external dose due to a particular radionuclide is proportional to its activity concentration, results are presented as dose factors, defined as a ratio of absorbed dose (nGy.h -1 ) to the activity concentration (Bq.kg -1 ), for each radionuclide. The radionuclides were assumed to be uniformly distributed in the building materials. Calculations were performed for concrete walls and results are presented for 40 K, 226 Ra, and 232 Th, taking in account, for dose calculations, all gamma emitters from 226 Ra and 232 Th decay chains. Sensitivity of the model was estimated by varying four of its input parameters within a reasonable range of applicability, while leaving all other parameters at fixed selected values. The parameters studied and respective ranges of variation were: for thickness, 5 to 60 cm; for density, 0.5 to 4 g.cm -3 ; for the room length, 1.5 to 10 m

  14. TPR Measurement for Co-60 Teletherapy Unit

    International Nuclear Information System (INIS)

    Heru-Prasetio; Nasukha

    2001-01-01

    Dosage delivery to a certain tissue within radiation field should be carefully determined. Although direct measurement is possible to accomplish, calculation is still required. The usage of TPR table in calculation will give benefit in dosage delivery to patients. Before standard TPR table is used, TPR value of Co-60 teletherapy unit should be determined and compared with standard TPR table. Comparison of measured TPR and standard TPR table which is provided by BJR, showed no significant differences for 8 x 8 cm 2 , 10 x 10 cm 2 , 15 x 15 cm 2 , 20 x 20 cm 2 , and 25 x 25 cm 2 square fields, in depth of 1 cm up to 6 cm. All result of new TPR is compared to TPR table in BJR and found differences of less than 1 %. These results is satisfactory and TPR from BJR table can be used as a basis in dose calculation. (author)

  15. Effect of Co-60 single escape peak on detection of Cs-137 in analysis of radionuclide from research reactor

    International Nuclear Information System (INIS)

    Kim, M. S.; Park, S. J.

    2006-01-01

    The effect of the single escape peak of 1173 keV gamma-rays from Co-60 on the detection of Cs-137 activity is analyzed. The single escape peak of 1173 keV gamma-rays from Co-60 is located at the 662 keV, which is very close to the energy of gamma-rays from Cs-137. This single escape peak may be mistaken for the gamma-ray peak from Cs-137 activity in the case of large area of 1173 keV peak. The detection of Cs-137 is very important to the judgment of the contamination or the leakage of the material containing the fission product like reactor pool water and in the several experiments for reactor physics such as burn-up estimation. In this work, the areas of the single escape peak of the 1173 keV gamma-rays from Co-60 are measured with several full energy peak areas by using the HPGe detector. The critical limit by which we can decide whether the net count of 662 keV peak due to Co-60 would be significant or not is deduced. For this detection system, when the area of full energy peak is larger than 4.5 million, the single escape peak of 1173 keV gamma-rays from Co-60 can be regarded as the single significant peak. Therefore, it is confirmed that the detection of the Cs-137 activity is affected by the Co-60 in this case. Conservatively, for this detection system, it is recommended that the area of 1173 keV peak of Co-60 would be less than 2 million for neglecting the effect of Co-60. (authors)

  16. Radiosensitivity of a soybean cultivation to Co-60 gamma rays

    International Nuclear Information System (INIS)

    Rios, H.; Labrada, A.; Rodriguez, R.; Hurtado, E.

    1987-01-01

    For the purpose of determining the effect of radiations on physiological and productive indexes in the G7R-315 soybean variety, experiments under field and laboratory conditions were carried out. The answers to straight-line irradiation doses on the basis of arkose. We reached to the conclusion that the height under laboratory conditions and the survival at the moment of crop bring about adequate indexes to determine dose-50 in the studied material

  17. Calculating concentration of inhaled radiolabeled particles from external gamma counting: External counting efficiency and attenuation coefficient of thorax

    International Nuclear Information System (INIS)

    Langenback, E.G.; Foster, W.M.; Bergofsky, E.H.

    1989-01-01

    We determined the overall external counting efficiency of radiolabeled particles deposited in the sheep lung. This efficiency permits the noninvasive calculation of the number of particles and microcuries from gamma-scintillation lung images of the live sheep. Additionally, we have calculated the attenuation of gamma radiation (120 keV) by the posterior chest wall and the gamma-scintillation camera collection efficiency of radiation emitted from the lung. Four methods were employed in our experiments: (1) by light microscopic counting of discrete carbonized polystyrene particles with a count median diameter (CMD) of 2.85 microns and tagged with cobalt-57, we delineated a linear relationship between the number of particles and the emitted counts per minute (cpm) detected by well scintillation counting; (2) from this conversion relationship we determined the number of particles inhaled and deposited in the lungs by scintillation counting fragments of dissected lung at autopsy; (3) we defined a linear association between the number of particles or microcuries contained in the lung and the emitted radiation as cpm detected by a gamma scintillation camera in the live sheep prior to autopsy; and (4) we compared the emitted radiation from the lungs of the live sheep to that of whole excised lungs in order to calculate the attenuation coefficient (ac) of the chest wall. The mean external counting efficiency was 4.00 X 10(4) particles/cpm (5.1 X 10(-3) microCi/cpm), the camera collection efficiency was 1 cpm/10(4) disintegrations per minute (dpm), and the ac had a mean of 0.178/cm. The external counting efficiency remained relatively constant over a range of particles and microcuries, permitting a more general use of this ratio to estimate number of particles or microcuries depositing after inhalation in a large mammalian lung if a similarly collimated gamma camera system is used

  18. Thyroid doses from external gamma-exposure following the Chernobyl accident

    International Nuclear Information System (INIS)

    Tretyakevich, Sergey; Kukhta, Tatyana; Minenko, Victor; Drozdovitch, Vladimir; Luckyanov, Nickolas; Gavrilin, Yury; Khrouch, Valeri; Shinkarev, Sergey

    2008-01-01

    Full text: An increase of thyroid cancer incidence among children in Belarus has been observed after the Chernobyl accident. The main contributor to the thyroid dose was caused by 131 I intake with fresh milk in 1986. Other contributions to the thyroid dose (external gamma-exposure, short-lived iodine isotopes, internal radiocesium) were small in comparison to the dose from 131 I intakes soon after the accident. However, exposures to external radiation continued for a number of years after the accident. Thyroid doses from external gamma-exposure following the Chernobyl accident were mainly caused by gamma-exposure to 24 nuclides: 95 Zr, 95 Nb, 99 Mo, 99 mTc, 103 Ru, 103m Rh, 106 Ru, 125 Sb, 125m Te, 131m Te, 131 I, 132 Te, 132 I, 133 I, 135 I, 134 Cs, 136 Cs, 137 Cs, 140 Ba, 140 La, 141 Ce, 144 Ce, 144 Pr, 239 Np. Data of personal interview were used to take into account the personal residence history for the time elapsed from the Chernobyl accident until the interview (10 to 15 years later). Cumulative thyroid doses caused by external gamma-exposure during the passage of the radioactive cloud and from the ground contamination following the Chernobyl accident have been reconstructed. The median thyroid dose from external gamma-exposure to ∼11,770 cohort members of an epidemiological study was estimated to be ∼6 mGy. There are ∼3,400 persons with external dose estimates that exceed 20 mGy. Exposure from radionuclides deposited on the ground was the main source of external dose. The contribution from the passing radioactive cloud to external dose was found to be negligible. (author)

  19. Feasibility study on production of Co-60 in PHWR

    Energy Technology Data Exchange (ETDEWEB)

    Park, Kyung Bae; Han, Hyon Soo; Joo, Po Kook

    2000-05-01

    The purpose of this study is to analyze the safeties and the economics for Co-60 production from Wolsung PHWR and to verify the feasibility on the manufacturing of the final Co-60 source for industrial irradiation. The feasibility of reactor conversion was carried out with KEPCO collaboration. Through the site survey on the experience of Gentililly-2 in Canada, a feasibility of plant conversion, changes in design, equipment and tools for Co-60 production was verified. It was estimated that the reactor conversion would not impose adverse impact on plant safety. For the encapsulation of radiation source and storage of the final products, a modification of concrete hot cell at KAERI was primary concerns. The installation and improvement of facilities are needed to avoid cross contamination and extra radiation exposure. Main items for these are pressure gauge, separated HEPA filter the ceiling separation, extra-shielding and ceiling hoist system. At present, storage pool has got admission based on 400 kCi. But it is necessary to seismic analysis and design improvement of shielding to store 10 MCi (Co-60) which is the estimated Co-60 capacity produced by 3 PHWRs. According to present investigation, a production of Co-60 by PHWR and RIPE was seemed to be an economically feasible business and it was also expected that a joint venture will be able to realize by cooperation with MDS Nordion Co.

  20. Feasibility study on production of Co-60 in PHWR

    International Nuclear Information System (INIS)

    Park, Kyung Bae; Han, Hyon Soo; Joo, Po Kook

    2000-05-01

    The purpose of this study is to analyze the safeties and the economics for Co-60 production from Wolsung PHWR and to verify the feasibility on the manufacturing of the final Co-60 source for industrial irradiation. The feasibility of reactor conversion was carried out with KEPCO collaboration. Through the site survey on the experience of Gentililly-2 in Canada, a feasibility of plant conversion, changes in design, equipment and tools for Co-60 production was verified. It was estimated that the reactor conversion would not impose adverse impact on plant safety. For the encapsulation of radiation source and storage of the final products, a modification of concrete hot cell at KAERI was primary concerns. The installation and improvement of facilities are needed to avoid cross contamination and extra radiation exposure. Main items for these are pressure gauge, separated HEPA filter the ceiling separation, extra-shielding and ceiling hoist system. At present, storage pool has got admission based on 400 kCi. But it is necessary to seismic analysis and design improvement of shielding to store 10 MCi (Co-60) which is the estimated Co-60 capacity produced by 3 PHWRs. According to present investigation, a production of Co-60 by PHWR and RIPE was seemed to be an economically feasible business and it was also expected that a joint venture will be able to realize by cooperation with MDS Nordion Co

  1. Response of reptilian live to external gamma irradiation

    International Nuclear Information System (INIS)

    Gupta, M.L.

    1990-01-01

    Adult healthy specimens of Uromastix hardwickii were exposed to three doses (i.e. 2.25, 4.50 and 9.00 Gy) of gamma radiation from a 60 Co source (experimental group). Five animals were sacrificed at each post-irradiation intervals of 1, 2, 3, 7 and 14 days. The liver was fixed in Bouin's fluid and after processing in a routine way, it was examined histologically. Five sham-irradiated animals (control group) were also sacrificed to compare the results. Low dose (i.e. 2.25 Gy) did not produce any apparent radiolesions in the liver. Changes in the form of cytoplasmic degranulation, swollen hepatocytes, pycnosis, increases in bile pigmentation were noticed after 4.50 and 9.00 Gy gamma ray exposure. Hyperaemia, widening of sinusoids and cytoplasmic vacuolation were also noticed in 9.00 Gy group. The liver exhibited normal picture on day 14 after exposure to both the doses. The radiolesions were found dose dependent. (author)

  2. External exposure from gamma radiation in uranium mines

    International Nuclear Information System (INIS)

    Thomson, J.E.

    1982-01-01

    Radiation doses received by workers in a high ore grade uranium mine are compared to those of other radiation workers and the need to be able to calculate the exposure rate from an ore body is indicated. The uranium-238 decay chain is presented and particular reference is made to the main gamma emitters and secular equilibrium of the members of the chain. Difficulties in dealing with a self attenuating volume source, in which scattering is important, are pointed out and traditional methods of solution are mentioned. It is shown that in the special case of an infinite ore body a simple solution may be obtained using the energy conservation principle. A straightforward method for calculating the exposure rate from an arbitrarily shaped ore body is given and corrections due to air attenuation, different soil types and possible lack of secular equilibrium are dealt with. The gamma ray spectrum from the ore is discussed with specific reference to the selection of suitable exposure monitors and the calculation of transmission through shields

  3. External gamma exposure to radon progeny in indoor air

    International Nuclear Information System (INIS)

    Fujimoto, Kenzo

    1985-01-01

    The external γ-exposure from radon progeny uniformly distributed in indoor air was estimated by a computer program that was developed. This program can calculate the fluence rate, exposure rate and average energy for any given point in a room of any given size. As numerical example, the exposure rate normalized to unit airborne activity is presented, together with the fluence-weighted and exposure-weighted average photon energies, for a room of representative geometry containing radon progeny in equilibrium. To cover other conditions encountered in practice, quantitative evaluations are additionally presented of the effect on the exposure brought by changes in certain parameters, such as equilibrium factor, wall thickness, room size and receptor position. The study has quantitatively substantiated the prevailing postulate that the effective dose equivalent due to external exposure resulting from normal indoor concentrations of airborne radon progeny in the room of representative geometry should only amount to 0.04 % of that from the internal exposure from the same sources, and that it should be of similarly negligible order compared with internal exposure also in the case of other room geometries. (author)

  4. Seasonal dynamics of Co60 accumulation by Elodea canadensis Rich

    International Nuclear Information System (INIS)

    Bochenin, V.F.; Chebotina, M.Ya.

    1975-01-01

    The seasonal dynamics of Co 60 accumulation by one of the most widely distributed fresh-water plants, elodea (Elodea canadensis Rich), were studied. Accumulation was shown to vary with the season. A very low coefficient of accumulation (500-700 units) was typical for the summer period (June to August). It increased in the fall, reached its highest values (3500-4000) in mid-winter (January), and dropped sharply in the spring. Radioisotope concentrations in the plant varied similarly. The cumulative capacity of plants for Co 60 may vary by a factor of 6 to 7 during the year. It is suggested that the seasonal changes in Co 60 accumulation may be caused by both differences in the physiological state of the plants at different times of the year, and by seasonal variations in the hydrochemical regime of the water reservoir. Experiments were done to clarify which of these mechanisms is the determining factor. (V.A.P.)

  5. Reconstruction of Co-60 Irradiation Facility No.1

    International Nuclear Information System (INIS)

    Nakamura, Yoshiteru; Takada, Isao; Kaneko, Hirohisa; Hirao, Toshio; Haneda, Noriyuki; Mitomo, Shouichi; Tachibana, Hiroyuki; Yoshida, Kenzou

    1989-01-01

    Cobalt Irradiation Facility No.1 was constructed in 1964 as the first large scale Co-60 irradiation facility equipped a deep water pool for source storage of Co-60 sources. Recently, the reconstruction of the facility was decided because the aging of various parts of the facility became remarkable and new research programs required upgradings of the facility. Important points of upgradings are as follows: A shielding capacity of the source storage and pool is increased to 55.5 PBq from 18.5 PBq. The opening in a floor of the irradiation room which is used for the source lifting in the room, is enlarged in order to utilize a large and high intensity source. Radiation resistance of the irradiation apparatus and installed equipments in the radiation room is increased for a high dose rate irradiation. Basic structure and shape of the facility building such as shielding, pool and building roof is not changed but electrical, mechanical equipments and systems are completely renewed. To increase a reliability, the irradiation apparatus and systems are also replaced with an improved and up-to-date one designed based on operation experiences of Co-60 facilities at TRCRE through many years. In addition, auxiliary equipments such as radiation monitors, manipulators, water treatment system and so on are replaced. This report presents the reconstruction of Co-60 Irradiation Facility No.1 stressing on the replacement and modification of the irradiation apparatus. (author)

  6. Transport of Co-60 from Argentina to abroad

    International Nuclear Information System (INIS)

    Cesario, R.; Pinamonti, M.

    1993-01-01

    The Co-60 bearing wastes from the Embalse Nuclear Power Plant, Argentina are transported to Canada, the United States and Mexico. Ocean transportation, terrestrial transportation, air transportation are applied, and the total activity in bulk material shipped reached 2.96x10 17 Bq. (J.P.N.)

  7. Sorption of Cs-137 and Co-60 in Natural Zeolites

    International Nuclear Information System (INIS)

    Chales Suarez, G.; Moreno Alvarez, D.; Coutin Correa, D.

    1996-01-01

    The sorption of Cs-137 and Co-60 in natural zeolites under different conditions was studied. The behaviour of samples of mineral and rock from different deposit of the country was obtained and the decontamination of radioactive waters containing both radionuclides was performed; as part of the research to determine its application in the treatment of radioactive wastes in the country

  8. Co-60 uptake in some young cereal plants

    International Nuclear Information System (INIS)

    Dumitru, R.O.

    1998-01-01

    The measure of Co-60 uptake by young cereal plants is dependent on the type of soil, plant and growth conditions. Depending on the size of the uptake, a plant can be used for industrial purposes, fodder, foodstuff or for possible decontamination of the soil. Although the requirement for cobalt in higher plants is little, their contamination with Co-60 can be of interest because this radionuclide belongs to the class of the radionuclides with a great radiotoxicity. The soil-to-plant transfer factor (TF) is a measure of the radionuclide uptake in the plant. In this paper the soil-to-plant TFs for Co-60 were determined for the whole aerial part of some young plants in the cereal class that, in this stage of the development, may be used as fodder. To determine soil-to-plant TFs, plants cultivated in pots in laboratory conditions were used. The method used is similar with the plantlet method of Neubauer and Schneider. We have determined some physical, chemical and mineralogical properties of the studied soil, a brown-reddish forest type soil. The soil-to-plant TFs were calculated on the basis of the Co-60 activities determined in plant and soil dried samples. For the vegetal samples the whole aerial part of the plants was measured in millet, wheat, barley and triticale. At harvest, only a few millet plants where flowered. The results of the measurements of soil-to-plant TFs of Co-60 are the following: 0.0315±0.0017 for millet, 0.0260±0.0014 for barley, 0.0140±0.0008 for wheat and 0.0491±0.0022 for triticale. These TFs were corrected for standard conditions and were compared with data from literature. The soil-to-plant TFs for Co-60 found in the aerial part of young cereals are close to those recommended for the fodder. The obtained values prove the strong dependence of the soil-to-plant TFs for Co-60 on the type of soil and plant. (author)

  9. Radiographic Co-60 in component of heavy equipment casting

    International Nuclear Information System (INIS)

    Djoli Soembogo, Harun Al Rasyid R dan Namad Sianta

    2016-01-01

    The application of radiography using isotope Co-60 source has been used on component of heavy equipment such as component of heavy equipment casting. Components of heavy equipment casting made through metal casting of carbon steel. This study tried applying digital radiography are using isotope Co-60 sources and using scanning positive film media of Epson V700 for digitization results of conventional radiographic films. This radiography is using film AGFA D7 and Fuji 100 to obtain a contrast medium, medium sensitivity and image quality is good. The purpose radiographic Co-60 at a component of heavy equipment casting is detecting indications of the shape and type casting defects of component of heavy equipment casting thus fit for use. Radiographic test of Co-60 has been carried out on component of heavy equipment casting with single wall single image method and the results of radiographic films digitization using scanning positive film media of Epson V700 with observation parameters casting defects. Time exposure of Co-60 radiation was 10 and 15 minutes hours for metal castings of carbon steel for thickness 20.00-50.00 mm by using activity 30.05 Ci and the perpendicular distance to the source of the film is 820 mm. Scanner positive film results in the form of digital radiography which allow for the transfer of digital data or digital computerized data storage. Radiographic test results on component of heavy equipment casting with single wall single image method produce the parameter casting defect of component of heavy equipment casting in position of critical area is found shrinkage that should be repaired and in position of safety area is not found defect indication so casting defect of component of heavy equipment casting are not acceptable according to standards referenced. (author)

  10. Historical estimates of external gamma exposure and collective external gamma exposure from testing at the Nevada Test Site. II. Test series after Hardtack II, 1958, and summary

    International Nuclear Information System (INIS)

    Anspaugh, L.R.; Ricker, Y.E.; Black, S.C.; Grossman, R.F.; Wheeler, D.L.; Church, B.W.; Quinn, V.E.

    1990-01-01

    The historical data on the cumulative individual external gamma exposures are tabulated for communities around the Nevada Test Site for the time periods of 1961 to the signing of the Limited Test Ban Treaty on 5 August 1963, and from then until 1975. The collective exposures during the two time periods are calculated to be 610 and 320 person-R, respectively. The total collective external gamma exposure from 1951 through 1975 for these communities s calculated to be 86,000 person-R. The area considered includes the countries of Clark, Lincoln, Nye, and White Pine in Nevada and the countries of Iron and Washington in Utah; inclusion of Salt Lake City would have substantially increased the calculated collective exposure because of the large population. The methods of calculation are reviewed. Also, the historical data on the assessment of dose via ingestion are reviewed with emphasis on the dose to the thyroid of infants living in St. George, UT, at the time of fallout from event HARRY on 19 May 1953

  11. Sorption of Cs-137 and Co-60 in Natural Zeolites; Sorcion de Cs-137 y Co-60 en zeolitas naturales

    Energy Technology Data Exchange (ETDEWEB)

    Chales Suarez, G; Moreno Alvarez, D; Coutin Correa, D [Agencia de Energia Nuclear, La Habana (Cuba)

    1996-07-01

    The sorption of Cs-137 and Co-60 in natural zeolites under different conditions was studied. The behaviour of samples of mineral and rock from different deposit of the country was obtained and the decontamination of radioactive waters containing both radionuclides was performed; as part of the research to determine its application in the treatment of radioactive wastes in the country.

  12. Temporal reduction of the external gamma dose rate due to 137Cs mobility in sandy beaches

    International Nuclear Information System (INIS)

    Rizzotto, M.; Toso, J.; Velasco, H.; Belli, M.; Sansone, U.

    2009-01-01

    In the present paper the contribution to the external gamma dose rate due o 137 Cs in soil as a function of time is presented. Sampling sites were elected along the Calabria and Basilicata Regions coastal beaches (southern art of Italy) to assess the external gamma dose rate in air, 1 m above the round level. A convection-dispersion model, with constant parameters was sed to approximate the radiocesium soil vertical migration. The model was calibrated using the initial 137 Cs activity deposition in this region Chernobyl fallout) and 137 Cs activity concentration down the soil profile, measured 10 years later. The dispersion coefficient and the advection velocity values, were respectively: 2.17 cm 2 y -1 and 0.32 cm -1 . The Radionuclide Software Package (RSP), which uses a Monte Carlo simulation code, was used to determine the primary 137 Cs gamma dose contribution in air 1 m above the ground surface. The resulting 137 Cs external dose rate ranged from 0.42 nGy h -1 in 1986, to 0.05 nGy h -1 in 007. (author)

  13. Verification by the FISH translocation assay of historic doses to Mayak workers from external gamma radiation

    Energy Technology Data Exchange (ETDEWEB)

    Sotnik, Natalia V.; Azizova, Tamara V. [Southern Urals Biophysics Institute (SUBI), Ozyorsk, Chelyabinsk Region (Russian Federation); Darroudi, Firouz [Leiden University Medical Center, Department of Toxicogenetics, Leiden (Netherlands); College of North Atlantic, Department of Health Science, Centre for Human Safety and Environmental Research, Doha (Qatar); Ainsbury, Elizabeth A.; Moquet, Jayne E.; Lloyd, David C.; Hone, Pat A.; Edwards, Alan A. [Public Health England, Chilton, Oxfordshire (United Kingdom); Fomina, Janna [Leiden University Medical Center, Department of Toxicogenetics, Leiden (Netherlands)

    2015-11-15

    The aim of this study was to apply the fluorescence in situ hybridization (FISH) translocation assay in combination with chromosome painting of peripheral blood lymphocytes for retrospective biological dosimetry of Mayak nuclear power plant workers exposed chronically to external gamma radiation. These data were compared with physical dose estimates based on monitoring with badge dosimeters throughout each person's working life. Chromosome translocation yields for 94 workers of the Mayak production association were measured in three laboratories: Southern Urals Biophysics Institute, Leiden University Medical Center and the former Health Protection Agency of the UK (hereinafter Public Health England). The results of the study demonstrated that the FISH-based translocation assay in workers with prolonged (chronic) occupational gamma-ray exposure was a reliable biological dosimeter even many years after radiation exposure. Cytogenetic estimates of red bone marrow doses from external gamma rays were reasonably consistent with dose measurements based on film badge readings successfully validated in dosimetry system ''Doses-2005'' by FISH, within the bounds of the associated uncertainties. (orig.)

  14. External gamma radiation dose studies in the proposed uranium mining areas of Andhra Pradesh, India

    International Nuclear Information System (INIS)

    Reddy, P.; Reddy, K.; Reddy, C.; Reddy, K.

    2006-01-01

    Natural radiation sources contribute the largest component to the total effective dose received by the human population. Among these sources, natural background gamma radiation shares a noteworthy amount. The present study aims at the establishment of baseline environmental gamma radiation data in the environs of proposed uranium mining areas of Andhra Pradesh, India. To this end, a systematic study has been undertaken using Thermoluminescence (T.L.) dosimeters and G.M. (Geiger - Muller) tube based survey meter. These levels are estimated both indoors and outdoors in the study area covering about 23 villages surrounding the proposed mining sites. The estimated external gamma radiation levels (air kerma) varied from 0.605 to 4.39 mGy.y -1 . The mean indoor to outdoor radiation level ratio is found to be 1.1 ± 0.1. The estimated mean equivalent doses due to external background radiation in the villages of the study area range from 1.03 to 2.83 mSv.y -1 with a mean of 2.34 ± 0.39 mSv.y -1 . (authors)

  15. External gamma irradiation-induced effects in early-life stages of zebrafish, Danio rerio

    International Nuclear Information System (INIS)

    Gagnaire, B.; Cavalié, I.; Pereira, S.; Floriani, M.; Dubourg, N.; Camilleri, V.; Adam-Guillermin, C.

    2015-01-01

    Highlights: • The present study aimed to evaluate the effects of gamma rays on zebrafish larvae. • Different techniques were used: gene expression, biochemistry, microscopy and macroscopical observations. • The results showed that gamma irradiation can alter embryo-larval development at several levels of organization. - Abstract: In the general context of validation of tools useful for the characterization of ecological risk linked to ionizing radiation, the effects of an external gamma irradiation were studied in zebrafish larvae irradiated for 96 h with two dose rates: 0.8 mGy/d, which is close to the level recommended to protect ecosystems from adverse effects of ionizing radiation (0.24 mGy/d) and a higher dose rate of 570 mGy/d. Several endpoints were investigated, such as mortality, hatching, and some parameters of embryo-larval development, immunotoxicity, apoptosis, genotoxicity, neurotoxicity and histological alterations. Results showed that an exposure to gamma rays induced an acceleration of hatching for both doses and a decrease of yolk bag diameter for the highest dose, which could indicate an increase of global metabolism. AChE activity decreased with the low dose rate of gamma irradiation and alterations were also shown in muscles of irradiated larvae. These results suggest that gamma irradiation can induce damages on larval neurotransmission, which could have repercussions on locomotion. DNA damages, basal ROS production and apoptosis were also induced by irradiation, while ROS stimulation index and EROD biotransformation activity were decreased and gene expression of acetylcholinesterase, choline acetyltransferase, cytochrome p450 and myeloperoxidase increased. These results showed that ionizing radiation induced an oxidative stress conducting to DNA damages. This study characterized further the modes of action of ionizing radiation in fish.

  16. External gamma irradiation-induced effects in early-life stages of zebrafish, Danio rerio

    Energy Technology Data Exchange (ETDEWEB)

    Gagnaire, B., E-mail: beatrice.gagnaire@irsn.fr [Institut de Radioprotection et de Sureté Nucléaire (IRSN), PRP-ENV/SERIS/LECO, Cadarache, Saint-Paul-lez-Durance 13115 (France); Cavalié, I. [Institut de Radioprotection et de Sureté Nucléaire (IRSN), PRP-ENV/SERIS/LECO, Cadarache, Saint-Paul-lez-Durance 13115 (France); Pereira, S. [Neolys Diagnostics, Lyon 69373 (France); Floriani, M.; Dubourg, N.; Camilleri, V.; Adam-Guillermin, C. [Institut de Radioprotection et de Sureté Nucléaire (IRSN), PRP-ENV/SERIS/LECO, Cadarache, Saint-Paul-lez-Durance 13115 (France)

    2015-12-15

    Highlights: • The present study aimed to evaluate the effects of gamma rays on zebrafish larvae. • Different techniques were used: gene expression, biochemistry, microscopy and macroscopical observations. • The results showed that gamma irradiation can alter embryo-larval development at several levels of organization. - Abstract: In the general context of validation of tools useful for the characterization of ecological risk linked to ionizing radiation, the effects of an external gamma irradiation were studied in zebrafish larvae irradiated for 96 h with two dose rates: 0.8 mGy/d, which is close to the level recommended to protect ecosystems from adverse effects of ionizing radiation (0.24 mGy/d) and a higher dose rate of 570 mGy/d. Several endpoints were investigated, such as mortality, hatching, and some parameters of embryo-larval development, immunotoxicity, apoptosis, genotoxicity, neurotoxicity and histological alterations. Results showed that an exposure to gamma rays induced an acceleration of hatching for both doses and a decrease of yolk bag diameter for the highest dose, which could indicate an increase of global metabolism. AChE activity decreased with the low dose rate of gamma irradiation and alterations were also shown in muscles of irradiated larvae. These results suggest that gamma irradiation can induce damages on larval neurotransmission, which could have repercussions on locomotion. DNA damages, basal ROS production and apoptosis were also induced by irradiation, while ROS stimulation index and EROD biotransformation activity were decreased and gene expression of acetylcholinesterase, choline acetyltransferase, cytochrome p450 and myeloperoxidase increased. These results showed that ionizing radiation induced an oxidative stress conducting to DNA damages. This study characterized further the modes of action of ionizing radiation in fish.

  17. R1800: a new Co 60 sealed source

    International Nuclear Information System (INIS)

    Freijo, Jose L.; Gomez, Gonzalo

    2005-01-01

    The increasing demand of Co 60 sealed sources in the international market has made necessary the development of new models of sealed sources. R 1800 type source up to 65 KCi has a design that allows to accommodate a wide spectrum of capsules with different specific activities. The company Dioxitek has developed the fabrication process and the design specifications needed to obtain the approval of the product. A first shipment of 100 KCi has been made with success to the United Kingdom in October of the current year. (author) [es

  18. UNDERWATER ANALYSIS OF IRRADIATED REACTOR SLUGS FOR Co-60 AND OTHER RADIONUCLIDES AT THE SAVANNAH RIVER SITE

    International Nuclear Information System (INIS)

    CASELLA, VITO

    2004-01-01

    Co-60 was produced in the Savannah River Site (SRS) reactors in the 1970s, and the irradiated cobalt reactor slugs were stored in a reactor basin at SRS. Since the activity rates of these slugs were not accurately known, assaying was required. A sodium iodide gamma detector was placed above a specially designed air collimator assembly, so that the slug was eight to nine feet from the detector and was shielded by the basin water. Also, 18 curium sampler slugs, used to produce Cm-244 from Pu-239, were to be disposed of with the cobalt slugs. The curium slugs were also analyzed with a High Purity Germanium (HPGE) detector in an attempt to identify any additional radionuclides produced from the irradiation. Co-60 concentrations were determined for reactor disassembly basin cobalt slugs and the 18 curium sampler slugs. The total Co-60 activity of all of the assayed slugs in this work summed to 31,783 curies on 9/15/03. From the Co-60 concentrations of the curium sampler slugs, the irradiation flux was determined for the known irradiation time. The amounts of Pu-238,-239,-240,-241,-242; Am-241,-243; and Cm-242,-244 produced were then obtained based on the original amount of Pu-239 irradiated

  19. Evaluation of Radiosensitivity of HeLa Cells Infected with Polio Virus Irradiated by Co 60

    Directory of Open Access Journals (Sweden)

    F Seif

    2008-04-01

    Full Text Available ABSTRACT: Introduction & Objective: The main purpose of radiotherapy is exposing enough doses of radiation to tumor tissue and protecting the normal tissues around it. Tumor dose for each session in radiotherapy will be considered based on radiosensitivity of the tissues. The presence of viral diseases in tumoral area can affect the radiosensitivity of cells. This study aimed to evaluate the radiosensitivity of Hela cells infected with poliomyelitis virus irradiated by Co 60. Materials & Methods: In this study, the radiosensitivity of HeLa cells, with or without the viral infection, after gamma radiation of cobalt 60, was assessed. Results: Results of comparison of the radisensitivity of infected and uninfected cells indicates that after 2 Gy irradiation by Co 60, polio infection in low, moderate and high virus load, increases the cell death by 20-30%, 30-40% and 70-90% respectively. Conclusion : Radiosensitivity of tumoral cells increase when they are infected with viral agents. Results of this study showed that non cancer diseases should be considered when prescribing dose fraction in radiotherapy of cancers.

  20. Improved estimates of external gamma dose rates in the environs of Hinkley Point Power Station

    International Nuclear Information System (INIS)

    Macdonald, H.F.; Thompson, I.M.G.

    1988-07-01

    The dominant source of external gamma dose rates at centres of population within a few kilometres of Hinkley Point Power Station is the routine discharge of 41-Ar from the 'A' station magnox reactors. Earlier estimates of the 41-Ar radiation dose rates were based upon measured discharge rates, combined with calculations using standard plume dispersion and cloud-gamma integration models. This report presents improved dose estimates derived from environmental gamma dose rate measurements made at distances up to about 1 km from the site, thus minimising the degree of extrapolation introduced in estimating dose rates at locations up to a few kilometres from the site. In addition, results from associated chemical tracer measurements and wind tunnel simulations covering distances up to about 4 km from the station are outlined. These provide information on the spatial distribution of the 41-Ar plume during the initial stages of its dispersion, including effects due to plume buoyancy and momentum and behaviour under light wind conditions. In addition to supporting the methodology used for the 41-Ar dose calculations, this information is also of generic interest in the treatment of a range of operational and accidental releases from nuclear power station sites and will assist in the development and validation of existing environmental models. (author)

  1. Estimate on external effective doses received by the Iranian population from environmental gamma radiation sources

    Energy Technology Data Exchange (ETDEWEB)

    Roozitalab, J.; Reza deevband, M.; Rastkhah, N. [National Radiation Protection Dept. Atomic Energy Organization (Iran, Islamic Republic of); Sohrabi, M. [Intenatinal atomic Energy Agency, Vienna (Austria)

    2006-07-01

    Concentration of natural radioactive materials, especially available U 238, Ra 226, Th 232, and K 40 in construction materials and soil, as well as absorb dose from cosmic rays, is the most important source of the people for effective doses from the environment radiation. In order to evaluate external effective dose, it has been carried out more than 1000 measurements in 36 cities by sensitive dosimeters to environmental gamma radiation for indoor and outdoor conditions in residential areas; which its results show that range of gamma exposure for inside of buildings in Iran is 8.7-20.5 {mu}R/h, and outdoor environments of different cities is 7.9-20.6 {mu}R/h, which their mean value are 14.33 and 12.62 {mu}R/h respectively. Meanwhile, it has been estimated that beam-absorbing ratio between indoor and outdoor in measured environments is 1.55, except contribution of cosmic rays. This studies show that average effective dose for each Iranian person from environmental gamma is 96.9 n Sv/h, and annually effective dose for every person is 0.848 mSv. (authors)

  2. Estimate on external effective doses received by the Iranian population from environmental gamma radiation sources

    International Nuclear Information System (INIS)

    Roozitalab, J.; Reza deevband, M.; Rastkhah, N.; Sohrabi, M.

    2006-01-01

    Concentration of natural radioactive materials, especially available U 238, Ra 226, Th 232, and K 40 in construction materials and soil, as well as absorb dose from cosmic rays, is the most important source of the people for effective doses from the environment radiation. In order to evaluate external effective dose, it has been carried out more than 1000 measurements in 36 cities by sensitive dosimeters to environmental gamma radiation for indoor and outdoor conditions in residential areas; which its results show that range of gamma exposure for inside of buildings in Iran is 8.7-20.5 μR/h, and outdoor environments of different cities is 7.9-20.6 μR/h, which their mean value are 14.33 and 12.62 μR/h respectively. Meanwhile, it has been estimated that beam-absorbing ratio between indoor and outdoor in measured environments is 1.55, except contribution of cosmic rays. This studies show that average effective dose for each Iranian person from environmental gamma is 96.9 n Sv/h, and annually effective dose for every person is 0.848 mSv. (authors)

  3. Determining of leakage rate of radionuclides Co-60 and Cs-137 in real conditioning; Odredjivanje brzine procurivanja radionuklida Co-60 i Cs-137 u realnim uslovima

    Energy Technology Data Exchange (ETDEWEB)

    Plecas, I; Peric, A; Kostadinovic, A [Institut za Nuklearne Nauke Boris Kidric, Belgrade (Yugoslavia)

    1989-07-01

    In this paper, results of examination of LEAKAGE rate of radionuclides Co-60 and Cs-137 in real condition are given. Radionuclides Co-60 and Cs-137 were immobilized by cement process and conditioned in concrete containers trying to make similar scenario for repository of radioactive waste materials as in engineering trench systems. Experiments were realized with evaporator bottom concentrate (EB) from Nuclear Power Plant Krsko in which the main radionuclides are Co-60 and Cs-137. (author)

  4. An analytical solution to the shielding of Co 60 teletherapy rooms based on a semiempirical equation of photon attenuation

    International Nuclear Information System (INIS)

    Saez, D.G.; Hernandez, L.; Borroto, M.; Figueredo, M.

    1996-01-01

    A semiempirical equation of polynomial-exponential type is presented to describe the transmission data of Co-60 gamma radiation in finite materials of concrete and lead. This equation and the expression obtained for the relationship of scatter-to-incident exposure made easy the developing in computer of an analytical solution for shielding calculations of Co 60 teletherapy rooms, based on the procedures of the NCRP 49 and Simpkin's method. The standard error in the estimation of parameters is less than 1.7 % except for the attenuation of 150 'o' scattered radiation in concrete that resulted in 6.3 % for one of them. The shielding calculations were compared with the data in NCRP 49 for the same conditions with a correlation better than 99 %

  5. Relative biological effectiveness (R.B.E.) of Cf-252 vs. acute Co-60 and low dose rate Cs-137 irradiation by spleen weight loss

    International Nuclear Information System (INIS)

    Maruyama, Y.; Feola, J.M.; Magura, C.; Beach, J.L.

    1986-01-01

    R.B.E. of Cf-252 on lymphoid tissue was assessed by radiation study of spleen weight loss following acute Co-60, and low dose rate (L.D.R.) Cs-137 and Cf-252 irradiations. Acute Co-60 and L.D.R. Cs-137 dose-response followed two component exponential curves with a 1.3-fold greater effect of L.D.R. Cs-137 vs. acute Co-60 on the first slope and 1.9-fold greater effect for the 2nd slope. L.D.R. Cf-252 response was 1.3 x greater than acute Co-60 but was 1.0 vs. L.D.R. Cs-137 for the first slope indicating a similar effect of Cf-252 mixed neutron/gamma radiation to L.D.R. gamma radiation in producing spleen shrinkage. There was no effect of different sequences and schedules of mixing acute Co-60 with Cf-252 irradiation observed by endogenous CFU-S survival. The R.B.E. of 1.0 - 1.9 indicates that lymphohemopoietic in vivo, presumably well oxygenated, does not respond acutely or as sensitively as hypoxic tumor where R.B.E. is 5 - 7. (author)

  6. A new programmable zone dosimeter for operational monitoring and measurement of external gamma radiation

    International Nuclear Information System (INIS)

    Toledo Acosta, Rene; Arteche Diaz, Raul; Mesa Perez, Guillermo; Fernandez Llanez, Sandra; Tamayo Garcia, Jose Antonio; Alonso Villanueva, Gilberto

    2010-01-01

    The detection and the measurement of the nuclear radiations have turn into an important item in the nuclear detectors application and specifically the Geiger Muller ones. Coming from theirs high detection sensibility, robust construction and relative simplicity of the associated circuit, the Geiger Tubes are still one of the most widely used detectors in all the application areas regarding physics and nuclear investigations A new design instrument is presented to be measures the ambient dose of external (gamma) radiation since 10 mSv/h. It consists of three elements: Geiger-Muller detector, the electronic board for the acquisition and control and the application software. The instrument communicates trough a USB interface to the Personal Computer only for adjust calibration parameters. The software was developed in the C programming language using PICC4, 08 compilers. (author)

  7. High-Resolution Gamma-Ray Imaging Measurements Using Externally Segmented Germanium Detectors

    Science.gov (United States)

    Callas, J.; Mahoney, W.; Skelton, R.; Varnell, L.; Wheaton, W.

    1994-01-01

    Fully two-dimensional gamma-ray imaging with simultaneous high-resolution spectroscopy has been demonstrated using an externally segmented germanium sensor. The system employs a single high-purity coaxial detector with its outer electrode segmented into 5 distinct charge collection regions and a lead coded aperture with a uniformly redundant array (URA) pattern. A series of one-dimensional responses was collected around 511 keV while the system was rotated in steps through 180 degrees. A non-negative, linear least-squares algorithm was then employed to reconstruct a 2-dimensional image. Corrections for multiple scattering in the detector, and the finite distance of source and detector are made in the reconstruction process.

  8. Androgenic function of the adrenal cortex in external gamma-irradiation

    International Nuclear Information System (INIS)

    Kirkov, N.; Jordanov, J.

    1987-01-01

    Urinary 17-ketosteroid (17-KS) excretion served to evaluate the androgenic function of the adrenal cortex and the gonads of male albino Wistar rats, following single external gamma-irradiation ( 137 Cs) with dose 4 Gy. A three-phase undulant dynamics in 17-KS excretion was established after irradiation at a high level of significance (p<0,001): a fall down to 19% during the first two days; a rise on day 15 up to 185% and a second fall down to 70% on day 25. On day 30 urinary 17-KS excretion returned to normal. The reduced 17-KS excretion during the first two days may be due to blocking of androgenic hormone secretion and excretion, to inhibited excretory renal function and to changes in the liver metabolic function

  9. Natural radioactivity and external gamma radiation exposure at the coastal Red Sea in Egypt

    International Nuclear Information System (INIS)

    Harb, S.

    2008-01-01

    Radionuclides which present in different beach sands are sources of external exposure that contribute to the total radiation exposure of human. In this work, superficial samples of beach sand were collected from the Red Sea coastline (Ras Gharib, Hurghada, Safaga, Qusier and Marsa Alam areas) and at 20 km on Qena-Safaga road. The distribution of natural radionuclides in sand beach samples was studied by gamma spectrometry. The activity concentrations of primordial and artificial radionuclides in samples that are collected from the coastal environment of the Red Sea were 19.2 ± 3 Bq kg -1 for 210 Pb, 21.1 ± 1 Bq kg -1 for 226 Ra, 22.7 ± 2 Bq kg -1 for 238 U, 1.0 ± 0.1 Bq kg -1 for 235 U, 11.6 ± 1 Bq kg -1 for 228 Ra, 13.0 ± 1 Bq kg -1 for 228 Th, 12.4 ± 1 Bq kg -1 for 232 Th, 930 ± 32 Bq kg -1 for 40 K and 1.2 ± 0.3 Bq kg -1 for 137 Cs. The mean external gamma-dose rate was 62.5 ± 3.2 nSv h -1 , 54.4 ± 2.8 nGy h -1 Ra equivalent activity (Ra eq ) was 107 ± 5.8 Bq kg -1 , 0.86 ± 0.04 Bq kg -1 for representative level index (Iγ) and effective dose rate was 0.067 ± 0.003 mSv y -1 in beach sand red sea, in air due to naturally occurring radionuclides. (authors)

  10. High-resolution imaging gamma-ray spectroscopy with externally segmented germanium detectors

    Science.gov (United States)

    Callas, J. L.; Mahoney, W. A.; Varnell, L. S.; Wheaton, W. A.

    1993-01-01

    Externally segmented germanium detectors promise a breakthrough in gamma-ray imaging capabilities while retaining the superb energy resolution of germanium spectrometers. An angular resolution of 0.2 deg becomes practical by combining position-sensitive germanium detectors having a segment thickness of a few millimeters with a one-dimensional coded aperture located about a meter from the detectors. Correspondingly higher angular resolutions are possible with larger separations between the detectors and the coded aperture. Two-dimensional images can be obtained by rotating the instrument. Although the basic concept is similar to optical or X-ray coded-aperture imaging techniques, several complicating effects arise because of the penetrating nature of gamma rays. The complications include partial transmission through the coded aperture elements, Compton scattering in the germanium detectors, and high background count rates. Extensive electron-photon Monte Carlo modeling of a realistic detector/coded-aperture/collimator system has been performed. Results show that these complicating effects can be characterized and accounted for with no significant loss in instrument sensitivity.

  11. External dose rates from gamma rays and activity concentrations in foodstuffs and herbage in eastern Europe

    International Nuclear Information System (INIS)

    Wilkins, B.T.; Dodd, N.J.; Bradley, E.J.

    1986-01-01

    The initial scarcity of reliable information in eastern European countries, coupled with the proximity of the Chernobyl installation, resulted in understandable concern among British nationals living in these areas or visiting them on a short-term basis. Accordingly, arrangements were made by the Foreign and Commonwealth Office (FCO) for the appropriate Embassies to send samples of milk, drinking water, grass and available fruit and vegetables to the Board's laboratories at Chilton for analysis. In addition, simple monitoring equipment was supplied to the Embassies for measurements of external dose rates from gamma rays out of doors. The first set of samples was collected in Moscow on May 3rd 1986. Most consignments arrived at Chilton within 24 hours of collection. Speed was important, not only because of the need for information but because vegetation needed to be sufficiently fresh to permit meaningful measurement. By the end of June 1986, the results of systematic monitoring programmes in eastern Europe were being disseminated more freely, so that frequent sampling by the Embassies was no longer considered necessary. Since that time samples have been received only occasionally from those Embassies where concern still persists. This report summarises the results of measurements and samples taken by June 30th 1986. Data for γ-ray emitting radionuclides in foodstuffs were issued to the FCO in a series of Measurement Reports. Here they are presented together with data for actinide element concentrations in a limited number of samples. Measurements of outdoor external dose rates made by the Embassies are also included

  12. External exposure doses due to gamma emitting natural radionuclides in some Egyptian building materials.

    Science.gov (United States)

    Moharram, B M; Suliman, M N; Zahran, N F; Shennawy, S E; El Sayed, A R

    2012-01-01

    Using of building materials containing naturally occurring radionuclides as (238)U, (232)Th and (40)K and their progeny results in an external exposures of the housing of such buildings. In the present study, indoor dose rates for typical Egyptian rooms are calculated using the analytical method and activity concentrations of natural radionuclides in some building materials. Uniform chemical composition of the walls, floor and ceiling as well as uniform mass concentrations of the radionuclides in walls, floor and ceiling assumed. Different room models are assumed to discuss variation of indoor dose rates according to variation in room construction. Activity concentrations of (238)U, (232)Th and (40)K content in eight samples representative Clay soil and different building materials used in most recent Egyptian building were measured using Inductively Coupled Plasma-Mass Spectrometry (ICP-MS). The specific activity for (238)U, (232)Th and (40)K, from the selected samples, were in the range 14.15-60.64, 2.75-84.66 and 7.35-554.4Bqkg(-1), respectively. The average indoor absorbed dose rates in air ranged from 0.005μGyh(-1) to 0.071μGyh(-1) and the corresponding population-weighted annual effective dose due to external gamma radiation varies from 0.025 to 0.345mSv. An outdoor dose rate for typical building samples in addition to some radiological hazards has been introduced for comparison. Copyright © 2011 Elsevier Ltd. All rights reserved.

  13. Dosimetric Consistency of Co-60 Teletherapy Unit- a ten years Study.

    Science.gov (United States)

    Baba, Misba H; Mohib-Ul-Haq, M; Khan, Aijaz A

    2013-01-01

    The goal of the Radiation standards and Dosimetry is to ensure that the output of the Teletherapy Unit is within ±2% of the stated one and the output of the treatment dose calculation methods are within ±5%. In the present paper, we studied the dosimetry of Cobalt-60 (Co-60) Teletherapy unit at Sher-I-Kashmir Institute of Medical Sciences (SKIMS) for last 10 years. Radioactivity is the phenomenon of disintegration of unstable nuclides called radionuclides. Among these radionuclides, Cobalt-60, incorporated in Telecobalt Unit, is commonly used in therapeutic treatment of cancer. Cobalt-60 being unstable decays continuously into Ni-60 with half life of 5.27 years thereby resulting in the decrease in its activity, hence dose rate (output). It is, therefore, mandatory to measure the dose rate of the Cobalt-60 source regularly so that the patient receives the same dose every time as prescribed by the radiation oncologist. The under dosage may lead to unsatisfactory treatment of cancer and over dosage may cause radiation hazards. Our study emphasizes the consistency between actual output and output obtained using decay method. The methodology involved in the present study is the calculations of actual dose rate of Co-60 Teletherapy Unit by two techniques i.e. Source to Surface Distance (SSD) and Source to Axis Distance (SAD), used for the External Beam Radiotherapy, of various cancers, using the standard methods. Thereby, a year wise comparison has been made between average actual dosimetric output (dose rate) and the average expected output values (obtained by using decay method for Co-60.). The present study shows that there is a consistency in the average output (dose rate) obtained by the actual dosimetry values and the expected output values obtained using decay method. The values obtained by actual dosimetry are within ±2% of the expected values. The results thus obtained in a year wise comparison of average output by actual dosimetry done regularly as a part of

  14. Mensuration of equivalent dose with personal dosemeters and instruments of radiological protection in the new operative magnitudes ICRU, for external fields of beta radiation. Part I. Study of the homogeneity of the response personal dosemeters leaves (cards G-1, TLD-100), in radiation fields of Co60

    International Nuclear Information System (INIS)

    Alvarez R, J.T.

    1994-01-01

    A sample of 40 composed personal dosemeters by cards model: G-l, (each card is made up of two TLD-100 crystals encapsulated in teflon), Harshaw trademark; those personal dosemeters present a free window and another with a filter of A1 of 171.7 mg cm -2 of mass thickness.The objective of the work is to select of this sample of 40 personal dosemeters a population with the same stocking and standard deviation. The technique used is that of comparison of stockings, (ANOVA; Variance Analysis, when samples of the same one were had size; and/or GLM, Widespread Lineal Models, when the samples were of different size), by means of the use of those Duncan statistics, SNK, Tukey, Gabriel; the results are validated proving the kindness of adjustment of the experimental data to a Normal distribution by means of the Shapiro-Wilks statistics.The experimental design used consists on a test of two vias: a via is the variable card with two levels, (crystal 1 and 2), the other via is the variable irradiation position with four levels, (LS=left superior, SR= right superior, LI= left Inferior, IR = right inferior). The irradiations carried out in blocks of four personal dosemeters in a gamma radiation beam range of Cobalt 60; carrying out three repetitions of the design. With object of proving the homogeneity of the filter of A1 in those personal dosemeters the experimental design was executed for those cards without personal dosemeters.They were also carried out tests of stockings to the readings of bottom and sensibility of the reader equipment, (Harshaw, model marks 2271), certain that doesn t exist differences for sequence of reading, but if in the stockings of the sensibility, (they were 4 different populations). The responses of the dosemeters were corrected subtracting him the reading correspondence of bottom and by sensibility of the reader equipment before subjecting them to the tests of stockings mentioned. Of the results of the tests of stockings for the cards with and

  15. TLD postal dose quality audit service for Co-60 beams in reference conditions in Cuba

    International Nuclear Information System (INIS)

    Gutierrez Lores, S.; Walwyn Salas, G.; Alonso Villanueva, G.

    2008-01-01

    This report presents the methodology and experience of the Cuban's Secondary Standard Dosimetry Laboratory for the implementation of postal dose quality audits service for Co-60 beams in reference conditions, using TLDs. Under coordinated research project (Contract 10794) were bought (TLD -100) Tl rods type JR 1152F made in China, with dimensions of 6 mm x 1 mm x 1 mm. All of these rods were identified individually with a consecutive number made over one of its sides, using a fine tip of graphite. The method used to determinate the individual sensibility of the TL detectors was: irradiating a group of them, with the same history of irradiation and readout (100 rods approximately), four serial times in the same geometrical conditions, to read them out and to attribute to each of them a sensitivity factor. This sensitivity factor is equal to average for the 4 cycle of irradiation and readout of the quote between the TL readout from dosimeter i and the mean of all values for each cycle. The TLD signal was read using HARSHAW 2000C/B reader. The results obtained in the external verification of the accuracy of the dose determination by the TLD system were performed in cooperation with IAEA Dosimetry Laboratory at Seibersdorf in different years are shown, the results obtained of the quality audits carried out to the different services of radiotherapy of the country are analysed also. The quality audits are an useful tool for the improvement of the accuracy in the dosimetry of clinical beams of radiotherapy with Co-60, contributing this way to the improvement of the life quality to cancer patients of the Cuban system of health. (author)

  16. Modelling population-level consequences of chronic external gamma irradiation in aquatic invertebrates under laboratory conditions

    Energy Technology Data Exchange (ETDEWEB)

    Lance, Emilie [Laboratoire de modelisation pour l' expertise environnementale (LM2E) Institut de Radioprotection et de Surete Nucleaire (IRSN), PRP-ENV, SERIS, Cadarache (France); Alonzo, Frederic, E-mail: frederic.alonzo@irsn.fr [Laboratoire d' ecotoxicologie des radionucleides (LECO) Institut de Radioprotection et de Surete Nucleaire (IRSN), PRP-ENV, SERIS, Cadarache (France); Garcia-Sanchez, Laurent [Laboratoire de biogeochimie, biodisponibilite et transferts des radionucleides (L2BT) Institut de Radioprotection et de Surete Nucleaire (IRSN), PRP-ENV, SERIS, Cadarache (France); Beaugelin-Seiller, Karine; Garnier-Laplace, Jacqueline [Laboratoire de modelisation pour l' expertise environnementale (LM2E) Institut de Radioprotection et de Surete Nucleaire (IRSN), PRP-ENV, SERIS, Cadarache (France)

    2012-07-01

    We modelled population-level consequences of chronic external gamma irradiation in aquatic invertebrates under laboratory conditions. We used Leslie matrices to combine life-history characteristics (duration of life stages, survival and fecundity rates) and dose rate-response curves for hatching, survival and reproduction fitted on effect data from the FREDERICA database. Changes in net reproductive rate R{sub 0} (offspring per individual) and asymptotic population growth rate {lambda} (dimensionless) were calculated over a range of dose rates in two marine polychaetes (Neanthes arenaceodentata and Ophryotrocha diadema) and a freshwater gastropod (Physa heterostropha). Sensitivities in R{sub 0} and {lambda} to changes in life-history traits were analysed in each species. Results showed that fecundity has the strongest influence on R{sub 0}. A delay in age at first reproduction is most critical for {lambda} independent of the species. Fast growing species were proportionally more sensitive to changes in individual endpoints than slow growing species. Reduction of 10% in population {lambda} were predicted at dose rates of 6918, 5012 and 74,131 {mu}Gy{center_dot}h{sup -1} in N. arenaceodentata, O. diadema and P. heterostropha respectively, resulting from a combination of strong effects on several individual endpoints in each species. These observations made 10%-reduction in {lambda} a poor criterion for population protection. The lowest significant changes in R{sub 0} and {lambda} were respectively predicted at a same dose rate of 1412 {mu}Gy h{sup -1} in N. arenaceodentata, at 760 and 716 {mu}Gy h{sup -1} in O. diadema and at 12,767 and 13,759 {mu}Gy h{sup -1} in P. heterostropha. These values resulted from a combination of slight but significant changes in several measured endpoints and were lower than effective dose rates calculated for the individual level in O. diadema and P. heterostropha. The relevance of the experimental dataset (external irradiation rather

  17. Method of suppressing the deposition of Co-60 to primary coolant pipeways in a nuclear reactor

    International Nuclear Information System (INIS)

    Hoshi, Michio; Tachikawa, Enzo; Goto, Satoshi; Sagawa, Chiaki; Yonezawa, Chushiro.

    1987-01-01

    Purpose: To suppress the deposition of Co-60 to primary coolant pipeways in a nuclear reactor. Method: To reduce the accumulation of Co-60 by causing chemical species of extremely similar chemical property with soluble Co-60 to be present together in coolants and replacing the deposition of Co-60 to the primary coolant pipeways in a nuclear reactor with that of the coexistent chemical spacies. Ni or Zn is used as the coexistet chemical spacies of similar chemical property with Co-60. The coexistent amount is from 5 to 10 times of the soluble Co-60 in the primary coolants. Ni or Zn solution adjusted with concentration is poured into and mixed with the coolants from a water feed source by using a high pressure constant volume pump. The amount of Co-60 taken into the pipeways caused by corrosion due to high temperature coolant is reduced to about 1/5 as compared with the case of Co-60 alone if 1 ppb of soluble Co-60 is present in water and 5 ppb of soluble Ni or Zn is added and, reduced to 1/12 if the amount of Ni or Zn is 10 ppb. (Kamimura, M.)

  18. Three-dimensional density field determination by external stationary detectors and gamma sources using selective scattering

    International Nuclear Information System (INIS)

    Kondic, N.; Jacobs, A.; Ebert, D.

    1983-01-01

    In many fields one needs to know the spatial density distribution; two-phase systems are of particular importance. In particular, gas-liquid mixtures play a role in power generation, chemistry, bio-medicine etc. An intrusion into the measured system is frequently undesired or not permitted. Therefore, external, non-invasive instrumentation has definite advantages. Photon-energy discrimination methods, measuring scattered fluxes, can employ stationary equipment; they need partial collimation or only protective shielding. The results are achieved with a higher information/irradiation ratio than is the case with transmission methods. The utilization a mesh of isogonic lines (each of them being characterised by its particular scattering angle) has several advantages when compared with the mesh of straight lines (''pencil beams'') used in tomography. The ultimate experimental arrangement employing Compton scattering has fan/fan beam geometry, i.e., wide angle emitting and receiving of gammas. The direct result of the measurement is a ''scattergram'', i.e., countrate versus scattered energy spectrum. Besides representing the ''signature'' of a two- or three-dimensional density distribution, it also enables the reconstruction of local density values. The report outlines the necessary analysis and presents experimental proof of principle

  19. Environmental external gamma radiation isodose map of Kinta and Batang Padang Districts, Perak

    International Nuclear Information System (INIS)

    Ismail, B.; Monawarah, N.M.Y.; Hng, P.W.; Sharifah Mastura, S.A

    2005-01-01

    The background radiation levels of any area, including those related to having deposit of NORM is important to be mapped out before being developed in order to assess their for potential radiological risk. A study was carried out map the environmental external gammas radiation dose rates in Kinta and Batang Padang Districts, Perak. The interpolation method in GIS was used to produce an isodose map based on prediction made from 13 different geological structure soil type combinations. Actual field measurements were carried using Sodium Iodine detectors. A predicted isodose map was plotted based on 5 dose rate classes, ranging from 0.16-0.57 Sv hr -1 . The area dose rates was increased to 5.00 Sv hr -1 once the dose rates contributed artificially by among plants to the study area was considered. Results also showed that the geosoil combination of steep land and acid intrusive rock areas radiates the highest dose rate levels (90.31 %) and most of these areas are in areas covered by hilly mountain. (Author)

  20. Transfer Factor of Co-60 and Cs-137 from Agricultural Soil to Agricultural Plant of Rice and Beans

    International Nuclear Information System (INIS)

    Suzie, D; Cerdas, T; Susilah, S; Umbara, H

    1996-01-01

    A study to estimate transfer factor of Co-60 and Cs-137 radionuclides from agricultural soil to agricultural plant of beans and rice in Serpong Nuclear Research Center Complex has been carried out. The soil used was that from off site Serpong Nuclear Research Center Complex, the agricultural plant samples were rice with variety of Cisadane, Situgintung, Seratus Malam, and Atomita 4, and for beans were peanut with variety of AH 1781 SI (parent) and A 20 psj (daughter), soybean with variety of Kerinci (parent) and Camar (daughter), and greenbean with variety of Manyar (parent) and Camar (daughter), which obtained from PAIR-BATAN Pasar Jumat. 10 kg of soil was put on the container which layered with plastic. The soil was contaminated with Co-60 and Cs-137 with activity concentration of 10 Bq/kg. Samples were counted with gamma spectrometer. The value of transfer factor was obtained by comparing activity concentration of agricultural plant with that of agricultural soil. The results of transfer factor of Co-60 for rice and beans were 0.12 x 10-2 and 1.05 x 10-2, respectively and the transfer factor of Cs-137 for rice and beans were 0.83 x 10-2 and 2.09 x 10-2, respectively. The gamma emmitter radionuclides counted from the soil of Serpong Nuclear Research Center Complex were Th-228, U-235, Ra-226, Ac-228 and K-40, with activities concentration as background were 35.39 - 101.60; 32.14 - 74.50; 23.37 - 28.57; 20.90 - 31.28 and 5.97 - 8.13 Bq/kg, respectively

  1. Early effects of external gamma irradiation on iodide metabolism in rat thyroid

    International Nuclear Information System (INIS)

    Niatsetskaya, Z.; Nadolnik, L.

    2006-01-01

    Full text of publication follows: The exposure of the thyroid gland to therapeutic doses of external gamma irradiation is frequently associated with thyroid dysfunction. Although late irradiation effects are well documented, little is still known about the early functional alterations in the thyroid subjected to radiation therapy. The aim of this study was to examine the early effect of single external gamma irradiation on iodide metabolism in the thyroid. The Wistar female rats were irradiated using a 60 Co installation with a constant capacity of 0.64 Gy/min. The doses used were 0.25, 0.5, 1, 2, 5 Gy. The animals were sacrificed after 24 hours following the irradiation. T he thyroid organ culture was cultivated during 24 h and than was irradiated with a single dose of 5 Gy. The thyroid tissue was assayed for thyro-peroxidase activity and concentrations of total, free and protein -binding iodide. It was shown that the 0.25 Gy irradiation depressed thyroid iodide uptake, which was manifested in decreasing total iodide by 25%. The same tendency was observed after the 0.5 Gy irradiation. In the 1, 2, 5 Gy groups, the concentrations of total and free iodide increased by 26 -34% and 50-68%, accordingly. The level of protein-binding iodide in these groups was within the control values. However, protein-binding/total iodide and protein binding/ free iodide ratios decreased by 17 -41%, suggesting inhibition of thyroglobulin iodination. Thyro-peroxidase (T.P.O.) plays a key role in thyroid hormone synthesis by catalyzing both the iodination of thyroglobulin and the coupling some of the iodo-tyrosyl residues. After 24 hours on irradiation, a 31.5-54% dose-dependent inhibition of T.P.O. activity was shown in the 1, 2 and 5 Gy groups. The irradiation of the rat thyroid organ culture with a single dose of 5 Gy also led to significant inhibition of T.P.O. by 56.91% after 2 hours. We compared the enzyme kinetics of thyro-peroxidase from thyroid microsomal fraction control and

  2. The effect of the build-up wall at the TLD calibration using Co-60

    International Nuclear Information System (INIS)

    Nariyama, N.

    2000-01-01

    Absorbed dose in thermoluminescent dosimeter (TLD) material at the calibration using Co-60 gamma rays depends on the TLD thickness and the wall material used for electric equilibrium condition. The relation was examined for LiF, BeO and CaF 2 TLDs sandwiched with PMMA, Teflon and Pyrex glass walls using a Monte Carlo transport code and compared with cavity ionization theory calculations. For the mismatched combination of LiF, BeO/Pyrex glass and CaF 2 /PMMA, it was found that the energy deposition did not change monotonously with TLD thickness from small cavity to large cavity value: a depression observed around 1-mm thickness for LiF/Pyrex glass and a peak around 0.6-mm thickness for CaF 2 /PMMA. The phenomena were explained by using different exponential attenuation coefficients β and β' for the weighting functions of cavity theory. Moreover, use of large cavity values was found to lead possibly to 3-5% errors in the calibration of thin TLDs. (author)

  3. Low-level multicounter {beta}/{gamma} systems with external guards in surface and shallow underground laboratories

    Energy Technology Data Exchange (ETDEWEB)

    Theodorsson, P [Iceland Univ. (Iceland). Science Inst.

    1997-03-01

    When weak samples are measured it is important that they can be given ample counting time in order to obtain satisfactory accuracy and that the background count rate can be checked well. This calls for a high counting capacity, which multidetectors can bring us. I will discuss development possibilities of low-level {beta}/{gamma} multidetector systems with an external anticosmic shield that will in many cases be operated in underground laboratories. These simple and low-cost system can frequently help us in increasing the number of detectors. Three concepts are combined in these systems: (1) multidetectors, (2) an external anticosmic (or guard) detector arrangement and (3) overburden shielding. (orig.)

  4. SOILD: A computer model for calculating the effective dose equivalent from external exposure to distributed gamma sources in soil

    International Nuclear Information System (INIS)

    Chen, S.Y.; LePoire, D.; Yu, C.; Schafetz, S.; Mehta, P.

    1991-01-01

    The SOLID computer model was developed for calculating the effective dose equivalent from external exposure to distributed gamma sources in soil. It is designed to assess external doses under various exposure scenarios that may be encountered in environmental restoration programs. The models four major functional features address (1) dose versus source depth in soil, (2) shielding of clean cover soil, (3) area of contamination, and (4) nonuniform distribution of sources. The model is also capable of adjusting doses when there are variations in soil densities for both source and cover soils. The model is supported by a data base of approximately 500 radionuclides. 4 refs

  5. External gamma radiation and mortality from cardiovascular diseases in the German WISMUT uranium miners cohort study, 1946-2008

    Energy Technology Data Exchange (ETDEWEB)

    Kreuzer, M.; Dufey, F.; Sogl, M.; Schnelzer, M.; Walsh, L. [Federal Office for Radiation Protection, Department of Radiation Protection and Health, Neuherberg (Germany)

    2013-03-15

    It is currently unclear whether exposure of the heart and vascular system, at lifetime accumulated dose levels relevant to the general public (<500 mGy), is associated with an increased risk of cardiovascular disease. Therefore, data from the German WISMUT cohort of uranium miners were investigated for evidence of a relationship between external gamma radiation and death from cardiovascular diseases. The cohort comprises 58,982 former employees of the Wismut company. There were 9,039 recorded deaths from cardiovascular diseases during the follow-up period from 1946 to 2008. Exposures to external gamma radiation were estimated using a detailed job-exposure matrix. The exposures were based on expert ratings for the period 1946-1954 and measurements thereafter. The excess relative risk (ERR) per unit of cumulative gamma dose was obtained with internal Poisson regression using a linear ERR model with baseline stratification by age and calendar year. The mean cumulative gamma dose was 47 mSv for exposed miners (86 %), with a maximum of 909 mSv. No evidence for an increase in risk with increasing cumulative dose was found for mortality from all cardiovascular diseases (ERR/Sv = -0.13; 95 % confidence interval (CI): -0.38; 0.12) and ischemic heart diseases (n = 4,613; ERR/Sv = -0.03; 95 % CI: -0.38, 0.32). However, a statistically insignificant increase (n = 2,073; ERR/Sv = 0.44; 95 % CI: -0.16, 1.04) for mortality from cerebrovascular diseases was observed. Data on smoking, diabetes, and overweight are available for subgroups of the cohort, indicating no major correlation with cumulative gamma radiation. Confounding by these factors or other risk factors, however, cannot be excluded. In conclusion, the results provide weak evidence for an increased risk of death due to gamma radiation only for cerebrovascular diseases. (orig.)

  6. Serum Gamma-Glutamyl-Transferase Independently Predicts Outcome After Transarterial Chemoembolization of Hepatocellular Carcinoma: External Validation

    Energy Technology Data Exchange (ETDEWEB)

    Guiu, Boris, E-mail: boris.guiu@chu-dijon.fr; Deschamps, Frederic [Institut Gustave Roussy, Department of Interventional Radiology (France); Boulin, Mathieu [University Hospital, INSERM U866 (France); Boige, Valerie; Malka, David; Ducreux, Michel [Institut Gustave Roussy, Department of Digestive Oncology (France); Hillon, Patrick [University Hospital, INSERM U866 (France); Baere, Thierry de [Institut Gustave Roussy, Department of Interventional Radiology (France)

    2012-10-15

    Purpose: An Asian study showed that gamma glutamyl transpeptidase (GGT) can predict survival after transarterial chemoembolization (TACE) of hepatocellular carcinoma (HCC). This study was designed to validate in a European population this biomarker as an independent predictor of outcome after TACE of HCC and to determine a threshold value for clinical use. Methods: In 88 consecutive patients treated by TACE for HCC, the optimal threshold for GGT serum level was determined by a ROC analysis. Endpoints were time-to-treatment failure (TTTF) and overall survival (OS). All multivariate models were internally validated using bootstrapping (90 replications). Results: Median follow-up lasted 373 days, and median overall survival was 748 days. The optimal threshold for GGT was 165 U/L (sensitivity: 89.3%; specificity: 56.7%; area under the ROC curve: 0.7515). Median TTTF was shorter when GGT was {>=}165 U/L (281 days vs. 850 days; P < 0.001). GGT {>=}165 U/L (hazard ratio (HR) = 2.06; P = 0.02), WHO PS of 2 (HR = 5.4; P = 0.002), and tumor size (HR = 1.12; P = 0.014) were independently associated with shorter TTTF. Median OS was shorter when GGT was {>=}165 U/L (508 days vs. not reached; P < 0.001). GGT {>=} 165 U/L (HR = 3.05; P = 0.029), WHO PS of 2 (HR = 12.95; P < 0.001), alfa-fetoprotein (HR = 2.9; P = 0.01), and tumor size (HR = 1.096; P = 0.013) were independently associated with shorter OS. The results were confirmed by bootstrapping. Conclusions: Our results provide in a European population the external validation of GGT as an independent predictor of outcome after TACE of HCC. A serum level of GGT {>=} 165 U/L is independently associated with both shorter TTTF and OS.

  7. Serum Gamma-Glutamyl-Transferase Independently Predicts Outcome After Transarterial Chemoembolization of Hepatocellular Carcinoma: External Validation

    International Nuclear Information System (INIS)

    Guiu, Boris; Deschamps, Frédéric; Boulin, Mathieu; Boige, Valérie; Malka, David; Ducreux, Michel; Hillon, Patrick; Baère, Thierry de

    2012-01-01

    Purpose: An Asian study showed that gamma glutamyl transpeptidase (GGT) can predict survival after transarterial chemoembolization (TACE) of hepatocellular carcinoma (HCC). This study was designed to validate in a European population this biomarker as an independent predictor of outcome after TACE of HCC and to determine a threshold value for clinical use. Methods: In 88 consecutive patients treated by TACE for HCC, the optimal threshold for GGT serum level was determined by a ROC analysis. Endpoints were time-to-treatment failure (TTTF) and overall survival (OS). All multivariate models were internally validated using bootstrapping (90 replications). Results: Median follow-up lasted 373 days, and median overall survival was 748 days. The optimal threshold for GGT was 165 U/L (sensitivity: 89.3%; specificity: 56.7%; area under the ROC curve: 0.7515). Median TTTF was shorter when GGT was ≥165 U/L (281 days vs. 850 days; P < 0.001). GGT ≥165 U/L (hazard ratio (HR) = 2.06; P = 0.02), WHO PS of 2 (HR = 5.4; P = 0.002), and tumor size (HR = 1.12; P = 0.014) were independently associated with shorter TTTF. Median OS was shorter when GGT was ≥165 U/L (508 days vs. not reached; P < 0.001). GGT ≥ 165 U/L (HR = 3.05; P = 0.029), WHO PS of 2 (HR = 12.95; P < 0.001), alfa-fetoprotein (HR = 2.9; P = 0.01), and tumor size (HR = 1.096; P = 0.013) were independently associated with shorter OS. The results were confirmed by bootstrapping. Conclusions: Our results provide in a European population the external validation of GGT as an independent predictor of outcome after TACE of HCC. A serum level of GGT ≥ 165 U/L is independently associated with both shorter TTTF and OS.

  8. Therapeutic results in ovarian cancer after replacement of conventional radiotherapy by Co-60 irradiation

    International Nuclear Information System (INIS)

    Kucera, H.; Szalay, St.; Weghaupt, K.; Heckenthaler, W.; Vienna Univ.

    1981-01-01

    The use of Co-60 screen and pendular irradiation instead of conventional radiotherapy has brought about an improvement in the 5-year survival rate in patients with more advanced stages of ovarian cancer. Although the general side effects of Co-60 irradiation are considered to be more unpleasant than those of X-ray and radium therapy, severe, reversible or irreversible damage to the urogenital tract and intestinal organs was diminished by accurate planning of Co-60 therapy, so that these complications occurred less frequently than with conventional radiotherapy. (author)

  9. Study on the production mechanism of Co-60 in the primary loop of HTR-10

    International Nuclear Information System (INIS)

    Wang Shouang; Xie Feng; Li Hong; Cao Jianzhu; Li Fu; Wei Liqiang

    2015-01-01

    Co-60 is an activated metallic erosion product, which is very important for waste management and decommissioning work of pressurized water reactor (PWR) power plants. Recent measurement on the samples from the primary loop of HTR-10 indicates the existence of Co-60. In current paper, the preliminary experimental results in HTR-10 will be introduced, and the production mechanism of Co-60 in the pebble bed high temperature gas-cooled reactors will be summarized and compared with that in PWRs and Germany High Temperature Nuclear Reactor (AVR). The further experiments with decomposing the post-irradiation graphite spheres of HTR-10 are put forward, which will promote the further study to testify the production sources of Co-60 and be of great significance in the waste minimization and the decommissioning work of HTR-10. (author)

  10. The comparison of Co-60 and 4MV photons matching dosimetry during half-beam technique

    International Nuclear Information System (INIS)

    Cakir, Aydin; Bilge, Hatice; Dadasbilge, Alpar; Kuecuecuek, Halil; Okutan, Murat; Merdan Fayda, Emre

    2005-01-01

    In this phantom study, we tried to compare matching dosimetry differences between half-blocking of Co-60 and asymmetric collimation of the 4MV photons during craniospinal irradiation. The dose distributions are compared and discussed. Firstly, some gaps with different sizes are left between cranial and spinal field borders. Secondly, the fields are overlapped in the same sizes. We irradiate the films located in water-equivalent solid phantoms with Co-60 and 4MV photon beams. This study indicates that the field placement errors in +/- 1mm are acceptable for both Co-60 and 4MV photon energies during craniospinal irradiation with half-beam block technique. Within these limits the dose variations are specified in +/- 5%. However, the setup errors that are more than 1mm are unacceptable for both asymmetric collimation of 4MV photon and half-blocking of Co-60

  11. The calculation of external gamma-ray doses from airborne and deposited radionuclides in the environmental code NECTAR

    International Nuclear Information System (INIS)

    Corbett, J.O.

    1982-02-01

    A computer program has been developed for the rapid evaluation of external gamma-ray doses from airborne and deposited radionuclide mixtures. Based on a gaussian dispersion model, the program calculates the dose at any position, including points high above ground level or upwind of the source. Meteorological frequency data for wind speed, direction, atmospheric stability and rainfall are fully taken into account. The calculational model assumes that the ground surface is perfectly flat and that gamma-ray paths are entirely in air; the possible errors caused by these and other assumptions are discussed, with suggested correction factors. The program applies various criteria to determine the best approximation or numerical integration method for each target point; execution times (on an IBM 370 machine) thus vary from less than 0.01s to about 0.3s per target point for a single weather category. The program has been incorporated in the environmental release program NECTAR. (author)

  12. Oxygen enhancement ratio (OER) to Neutron and Co-60 γ ray

    International Nuclear Information System (INIS)

    Kim, Mi Sook; Ji, Young Hoon; Lee, Yong Min; Kim Kyeoung Jung

    1997-01-01

    Experiments in vitro, using human cell lines was carried out in order to establish whether or not there was a difference between oxygen enhancement ratio (OER) of neutron and Co-60 γ-ray and to determine OER dependence on radiation dose. MG-63 cell line and H-460 cell line were defined as the most sensitive cell line to neutron among our laboratory holding cell lines through preliminary study. Anoxia as was produced in glove box. The box was flushed for one hour with a mixture of 5 % CO 2 in ultrapure N 2 (total oxygen concentration < 10 ppm) and irradiated with neutron and Co-60 γ-ray. Oxic condition was same as anoxic condition except being irradiated in general air condition. The lower OER was observed in neutron than in Co-60 γ-ray. The dose dependence of OER was observed in neutron and Co-60 γ-ray all. But the dose dependence of the OER is somewhat larger for Co-60 γ-ray than for neutron. In the range of 1 to 8 Gy, the OER for photon and neutron range from 1.54 to 1.94 and 1.23 to 1.26 in MG-63 cell line. In case of H-460 the OER for Co-60 γ-ray and neutron range from 1.24 to 1.60 and 1.06 to 1.07 respectively. (author). 19 refs., 5 tabs., 5 figs

  13. Fertility and fertilizing ability of cotton pollen following γ-radiation (Co60)

    International Nuclear Information System (INIS)

    Filatov, P.S.

    1976-01-01

    The effect of Co 60 gamma radiation on the fertility and fertilizing ability of ripe cotton (Tashkent-2 variety) pollen was studied. Radiation doses were 0.5, 1, 1.5, 2, 3, 4, 5, and 10kR. The generally accepted cross-pollination method was used. The viability of the pollen after irradiation was determined by the Shardakov and aceto-carmine dye method. Determination of the peroxidase activity, which in this case was used as an index of the pollen viability, made it possible to assess its physiological state. Non-irradiated flowers were used as controls. It was shown that the pollen viability depended on the radiation dose. Doses from 0.5 to 2 kR had no effect on the peroxidase activity. Irradiation decreased the percentage of viable pollen somewhat (compared to controls). A similar relation to irradiation was observed in the pollen color in the aceto-carmine test for fertility. Doses of 5-10 kR decreased the percentage of fertility of the pollen. An important factor in evaluating the radiation sensitivity of cotton pollen is the number and type of bound bolls and seeds. Studies showed that the number of bound bolls depends on the radiation dose. With doses of 0.5 and 1.5 kR an average of 78.6% bound bolls formed, compared to 80.0% in the controls. With 1 kR the number of bound rolls formed, compared to 80.0% in the controls. With these doses the shape and size of the bolls did not differ from those in the controls; the average weight was 4.3 g. Doses of 2.3 and 4kR gave an average of 66% bound bolls, i.e., 14% different from the controls. With increase in the radiation dose, the size and shape of the bolls changed significantly. Doses of 5 and 10 kR had a lethal action on formation of filled-out seed; not one filled seed was found. Thus, pollen treated with different gamma radiation doses retains its viability, depending on the radiation dose

  14. Study on Public Exposure and External Radiation Level at Gamma Green House and around MINT Dengkil Complex Boarder

    International Nuclear Information System (INIS)

    Faizal Azrin Abdul Razalim; Ismail Sulaiman; Khairuddin Mohamad Kontol; Ahmad Bazlie Abdul Kadir; Noor Fadilla Ismail; Hassan Sham; Ahmad Zainuri Mohd Dzomir

    2014-01-01

    This paper will discussing on the measurement of external radiation and the dose level which is acceptable to the public around the Gamma Green House and the border between Malaysian Nuclear Agency and housing project developed by Mah Sing Group. This research is made to verify the level of safety, especially for civilians residing in this area and to ensure compliance with the limit that has been set by the authorities, AELB (BSS/2010). Measurement method used in this research by using survey meter, TLD and OSL. (author)

  15. An experimental study on the effects of Co-60 irradiation in the rat periodontium

    Energy Technology Data Exchange (ETDEWEB)

    Park, Dai Hee; Lee, Sang Hee [Dept. of Oral Radiology, Division of Dentistry, Kyung Hee University, Seoul (Korea, Republic of)

    1986-11-15

    It is known that radiation therapy is a kind of treatment choices of the maxillofacial tumors. This study is designed to investigate the irradiation effects on rat's periodontal tissues as functional tissues which relate to tooth-support, hard tissue formation and destruction. 20 rats (Sprague-Dowley branch, male) were devided into control group of 4 and experimental groups of 16. Experimental group was singly expose to Co-60 irradiation with 10 Gy in the head and neck region. Animals were sacrificed on 2 days, 2 weeks after the irradiation. The specimens were ob served by histopathological examination employing H-E stain, van-Gieson stain and PA-ACH fluorescent stain. The results were as follows: 1. Cementoblasts and osteoblasts were gradually lost and rearranged along the external surfaces of the cementum and alveolar bone, but osteoclasts were almost not affected.2. The cell numbers of the periodontal ligament were decreased due to the cellular atrophy and degeneration, but recovered almost normal on the 3rd week after irradiation. 3. The collagen fibers within the periodontal ligament were irregularly oriented, became finer and decreased in num ber. 4. The vessels of the periodontal ligament were decreased at the initial stage but increased again on the 2nd wee k after irradiation, and the hemorrhagic appearances, occurred within the tissues, due to the arterial destruction, were lasted until 3 weeks after irradiation. 5. The glycogen within the the periodontal ligament was gradually increased and stored in the matrices of the cemental side on the 1st week after irradiation, but recovered almost normally on the 3rd week after irradiation.

  16. An experimental study on the effects of Co-60 irradiation in the rat periodontium

    International Nuclear Information System (INIS)

    Park, Dai Hee; Lee, Sang Hee

    1986-01-01

    It is known that radiation therapy is a kind of treatment choices of the maxillofacial tumors. This study is designed to investigate the irradiation effects on rat's periodontal tissues as functional tissues which relate to tooth-support, hard tissue formation and destruction. 20 rats (Sprague-Dowley branch, male) were devided into control group of 4 and experimental groups of 16. Experimental group was singly expose to Co-60 irradiation with 10 Gy in the head and neck region. Animals were sacrificed on 2 days, 2 weeks after the irradiation. The specimens were ob served by histopathological examination employing H-E stain, van-Gieson stain and PA-ACH fluorescent stain. The results were as follows: 1. Cementoblasts and osteoblasts were gradually lost and rearranged along the external surfaces of the cementum and alveolar bone, but osteoclasts were almost not affected.2. The cell numbers of the periodontal ligament were decreased due to the cellular atrophy and degeneration, but recovered almost normal on the 3rd week after irradiation. 3. The collagen fibers within the periodontal ligament were irregularly oriented, became finer and decreased in num ber. 4. The vessels of the periodontal ligament were decreased at the initial stage but increased again on the 2nd wee k after irradiation, and the hemorrhagic appearances, occurred within the tissues, due to the arterial destruction, were lasted until 3 weeks after irradiation. 5. The glycogen within the the periodontal ligament was gradually increased and stored in the matrices of the cemental side on the 1st week after irradiation, but recovered almost normally on the 3rd week after irradiation.

  17. A theoretical study for the real-time assessment of external gamma exposure using equivalent-volume numerical integration

    International Nuclear Information System (INIS)

    Han, Moon Hee

    1995-02-01

    An approximate method for estimating gamma external dose due to an arbitrary distribution of radioactive material has been developed. For the assessment of external gamma dose, the space over which radioactive material is distributed has been assumed to be composed of hexagonal cells. The evaluation of three-dimensional integration over the space is an extremely time-consuming task. Hence, a different approach has been used for the study, i.e., a equivalent-volume spherical approach in which a regular hexahedron is modeled as a equivalent-volume sphere to simplify the integration. For the justification of the current approach, two case studies have been performed: a comparison with a point source approximation and a comparison of external dose rate with the Monte Carlo integration. These comparisons show that the current approach gives reasonable results in a physical sense. Computing times of the developed and Monte Carlo integration method on VAX system have been compared as a function of the number of hexagonal cells. This comparison shows that CPU times for both methods are comparable in the region of small number of cells, but in the region of large number, Monte Carlo integration needs much more computing times. The proposed method is shown to have an accuracy equivalent to Monte Carlo method with an advantage of much shorter calculation time. Then, the method developed here evaluates early off-site consequences of a nuclear accident. An accident consequence assessment model has been integrated using Gaussian puff model which is used to obtain the distribution of radioactive material in the air and on the ground. For this work, the real meteorological data measured at Kori site for 10 years (1976 - 1985) have been statistically analyzed for obtaining site-specific conditions. The short-term external gamma exposures have been assessed for several site-specific meteorological conditions. The results show that the extent and the pattern of short-term external

  18. A New In-core Production Method of Co-60 in CANDU Reactors

    Energy Technology Data Exchange (ETDEWEB)

    Lyu, Jinqi; Kim, Woosong; Kim, Yonghee [KAIST, Daejeon (Korea, Republic of); Park, Younwon [BEES Inc, Daejeon (Korea, Republic of)

    2016-05-15

    This study introduces an innovative method for Co-60 production in the CANDU6 core. In this new scheme, the central fuel element is replaced by a Co-59 target and Co-60 is obtained after the fuel bundle is discharged. It has been shown that the new method can produce significantly higher amount of Co-60 than the conventional Co production method in CANDU6 reactors without compromising the fuel burnup by removing some (<50%) of the adjuster rods in the whole core. The coolant void reactivity is noticeably reduced when a Co-59 target is loaded into the central pin of the fuel bundle. Meanwhile, the peak power in a fuel bundle is just a little higher due to the central Co-59 target than in conventional CANDU6 fuel design. The basic technology for Co-60 producing was developed by MDS Nordion and Atomic Energy of Canada Limited (AECL) in 1946 and the same technology was adapted and applied in CANDU6 power reactors. The standard CANDU6 reactor has 21 adjuster rods which are fully inserted into the core during normal operation. The stainless steel adjuster rods are replaced with neutronically-equivalent Co-59 adjusters to produce Co-60. Nowadays, the roles of the adjuster rods are rather vague since nuclear reactors cannot be quickly restarted after a sudden reactor trip due to more stringent regulations. In some Canadian CANDU6 reactors, some or all the adjuster rods are removed from the core to maximize the uranium utilization.

  19. External Shock in a Multi-bursting Gamma-Ray Burst: Energy Injection Phase Induced by the Later Launched Ejecta

    Science.gov (United States)

    Lin, Da-Bin; Huang, Bao-Quan; Liu, Tong; Gu, Wei-Min; Mu, Hui-Jun; Liang, En-Wei

    2018-01-01

    Central engines of gamma-ray bursts (GRBs) may be intermittent and launch several episodes of ejecta separated by a long quiescent interval. In this scenario, an external shock is formed due to the propagation of the first launched ejecta into the circum-burst medium and the later launched ejecta may interact with the external shock at a later period. Owing to the internal dissipation, the later launched ejecta may be observed at a later time (t jet). In this paper, we study the relation of t b and t jet, where t b is the collision time of the later launched ejecta with the formed external shock. It is found that the relation of t b and t jet depends on the bulk Lorentz factor (Γjet) of the later launched ejecta and the density (ρ) of the circum-burst medium. If the value of Γjet or ρ is low, the t b would be significantly larger than t jet. However, the t b ∼ t jet can be found if the value of Γjet or ρ is significantly large. Our results can explain the large lag of the optical emission relative to the γ-ray/X-ray emission in GRBs, e.g., GRB 111209A. For GRBs with a precursor, our results suggest that the energy injection into the external shock and thus more than one external-reverse shock may appear in the main prompt emission phase. According to our model, we estimate the Lorentz factor of the second launched ejecta in GRB 160625B.

  20. Radon concentration in air and external gamma dose rate. Is there a correlation?

    International Nuclear Information System (INIS)

    Yoshimura, E.M.; Umisedo, N.K.; Marcos Rizzotto; Hugo Velasco; Valladares, D.L.

    2016-01-01

    We checked the existence of correlations between experimentally determined radon concentration in indoor air and gamma dose rate, in different environments: residences, workplaces in subway stations and radiotherapies, and a gold mine. Except for the mine environment, where a linear correlation (r 2 = 0.86) was obtained with statistical significance, we found no correlations between those quantities. Both radiation sources are originated from natural radionuclides, nonetheless the observation of correlations depends on various conditions, as we discuss here. (author)

  1. Calculation of uncertainties in the protocol of dosimetry for Co 60 beams in Radiotherapy

    International Nuclear Information System (INIS)

    Velazquez M, S.; Carrera M, F.; Sanchez S, J.

    1998-01-01

    The objective in this work is to show how the uncertainty is possible to know in the determination of the absorbed dose in Co 60 photon beams and to establish in a rational form, tolerance levels for this. It is took as base the spanish protocol of dosimetry in Radiotherapy. We have been centered in a Co 60 beam. We utilized the statistical theory of little samples. We allowed to suggest a new approach about the treatment of the tolerance levels and the uncertainty of the measurement. After two years of experience in the practical hospitable application we have gotten to put around 1 % uncertainty in the absolute dosimetry of the Co 60 beam. The presented protocol allows to execute the accuracy requirements in the determination of absorbed doses. (Author)

  2. Analytical solution for shielding in teletherapy rooms with Co60 according to semiempirical equation of attenuation

    International Nuclear Information System (INIS)

    Saez, D.G.; Borroto, M.

    1996-01-01

    The paper presents the parameters for a semiempirical equation of an exponential-polynomial type for the description of the transmission data of the different qualities of the Co-60 radiation in finite means of concrete (2350 kg m -3 ) and lead. This equation and the expression obtained for the relationship of scatter-to-incident exposure, help in the development of a computerized analytical solution of the Simpkin's method for shielding calculations in Co-60 teletherapy rooms. The results were compared with the values offered in the NCRP-49 for the same conditions, obtaining an acceptable correlation. (authors). 8 refs., 2 tabs

  3. A simple formula for depth dose calculation for Co-60 teletherapy beam dosimetry

    International Nuclear Information System (INIS)

    Tripathi, U.B.; Kelkar, N.Y.

    1979-01-01

    Knowledge of dose at all points of interest in the plane of tumour is essential for treatment planning. A very simple formula for scatter dose calculation along the central axis of a Co-60 beam has been derived. This formula uses primary dose at depth d, scatter air ratio at the depth of maximum ionisation and the effective depth of the volume, irradiating the medium. The method for calculation of percentage depth dose at any point in the principal plane has been explained in detail. The simple form of the formulation will help in improving the treatment plans for treatments of lesions using Co-60 teletherapy machines. (orig.) [de

  4. Studies on external gamma dose rates in air around Hassan city, Karnataka

    International Nuclear Information System (INIS)

    Shashikumar, T.S.; Gowda, Shivalinge; Chandrashekar; Shivakumar, B.C.

    2017-01-01

    Gamma-ray dose rates in air have been measured in the environment of Hassan City. The measurements were done from 15 locations in and around Hassan city at 1m above from the ground surface using a light weight portable radiation survey meter (Scintillometer) which is suited for radiometric, and environmental surveys. The meter reading fluctuates around a mean value and is proportional to the count rate detected by the unit. This is because of the random nature of radioactivity. The detailed results of the study will be presented. (author)

  5. Molecular level analyses of mechanical properties of PTFE sterilized by Co-60 γ-ray irradiation for clinical use

    Science.gov (United States)

    Furuta, Masakazu; Matsugaki, Aira; Nakano, Takayoshi; Hirata, Isao; Kato, Koichi; Oda, Takashi; Sato, Mamoru; Okazaki, Masayuki

    2017-10-01

    Recently, Co-60 gamma-ray irradiation has become markedly popular for the sterilization of biomedical materials, including expanded PTFE. However, its effect on the properties of PTFE has not been thoroughly examined. In this study, changes in the properties of PTFE before and after irradiation were analyzed physicochemically and discussed crystallographically. The tensile breaking strengths of PTFE decreased markedly on irradiation at 1 kGy, and were maintained at almost one fourth of the original value (44.3±2.5 N/mm2) ranging from 5 to 100 kGy. XPS analysis indicated that the atomic concentrations of carbon (C) and fluorine (F) of PTFE were not different among samples irradiated at various dosages. Raman spectra of PTFE showed a slight increase of the absorption peak intensity at 735 cm-1 in an irradiation dosage-dependent manner. X-ray diffraction showed that the crystal size of PTFE (56.7±1.0 nm) became smaller after radiation at 100 kGy (48.5±0.6 nm). These results are consistent with the above results of Raman analysis. It is suggested that the observed changes in the mechanical properties of PTFE may be due to nano-scale C-C bond scission by gamma ray irradiation, and not due to the formation of micro-scale cracks.

  6. Evaluation of gamma prime volume fractions and lattice misfits in a nickel base superalloy using the external standard X-ray diffraction method

    Energy Technology Data Exchange (ETDEWEB)

    Tiley, J., E-mail: jaimie.tiley@wpafb.af.mil [Air Force Research Laboratory, Materials and Manufacturing Directorate, WPAFB, OH (United States); Viswanathan, G.B. [Air Force Research Laboratory, Materials and Manufacturing Directorate, WPAFB, OH (United States); Hwang, J.Y. [Materials Engineering Department, University of North Texas, Denton, TX (United States); Shiveley, A. [Air Force Research Laboratory, Materials and Manufacturing Directorate, WPAFB, OH (United States); Banerjee, R. [Materials Engineering Department, University of North Texas, Denton, TX (United States)

    2010-11-25

    The unconstrained lattice parameters and volume fractions of {gamma}' for a low misfit nickel based superalloy were evaluated using X-ray diffraction techniques. Extraction techniques were used to provide unconstrained {gamma}' powders for both water quenched and slow cooled samples that were aged at 760 deg. C for 0, 25, 50, 100, and 200 h. The external standard method was used to determine the volume fraction for the unaged water quenched sample and the slow cooled sample aged for 200 h. These two extremes in processing conditions provided an increase in the total volume fraction of {gamma}'.

  7. Co-60 and Ca-45 autoradiography in cerebral ischemia in the rat

    NARCIS (Netherlands)

    Stevens, H; Krop-van Gastel, W; Korf, J

    1998-01-01

    Radioisotopes of divalent Co (Co-57 in Single photon emission tomography (SPECT)and Co-55 in positron emission tomography (PET) have clinically been applied to visualize Ca related brain damage. The cerebral uptake of Ca-45 and Co-60 in a unilateral stroke model in the rat was compared; 100 mu Ci

  8. Soil-plant transfer factors of Co-60 for alfalfa lettuce and spinach

    International Nuclear Information System (INIS)

    Dumitru, Radu Octavian

    1997-01-01

    The transfer of Co-60 from soil into plants is a less studied problem. Soil-plant transfer factors for Co-60 known from literature vary by about four orders of magnitude for each kind of plants. We have calculated the average values and have determined the field of variability of the known transfer factors. These indicated us that alfalfa, lettuce and spinach have in this order the greatest absorption capacity of Co-60 from soil. We have determined the physical, chemical and mineralogical properties of the utilized soil. This is a brown reddish forest type soil. The plants have been cultivated in pots by plantlet method of Neubauer and Schneider. The results of our measurements of soil-to-plant transfer factors of 60-Co are the followings: 0.0612 ± 0.0047 for alfalfa, 0.0960 ± 0.0072 for lettuce and 0.1446 ± 0.0107 for spinach. These values prove the strong dependence of the type of soil and plant of the soil-plant transfer factors for Co-60. (author)

  9. A geostatistical investigation of the spatial variation of external gamma exposure in urban area of Pocos de Caldas Plateau

    International Nuclear Information System (INIS)

    Silva, Nivaldo C.; Macacini, Jose F.; Taddei, Maria H.T.; Montano, Marcelo; Fontes, Aurelio T.

    2008-01-01

    Full text: The Pocos de Caldas Plateau has been recognized as High Level of Natural Radiation Area for a long time. It consists in an alkaline intrusion with some uranium and thorium anomalies, where the first Brazilian uranium mining and milling facilities is located. Due to these facts, the population of Pocos de Caldas city shows a great deal of concern about radiation health effects. This perception of the risks of radiation exposure leads to much confusion among the population that attributes an imaginary excess (without an scientific support) of cancer cases and deformities in newborns in the city to radiation. In order to obtain information for help radiation risks management by government and to explore the spatial variation external gamma exposure a survey in the urban area of Pocos de Caldas city was done. The measurements were performed using a Mobile Radioactivity Measurement System - Mobisys (ESM Eberline model FHT 1376). The system consists of a high-sensitivity 5-liter scintillation detector, an electronic for measurement system that is able to on-line separate natural and artificial gamma radiation (Natural Background Rejection Detector NBR), one compact Global Positioning System GPS and a computer (notebook). Data was collected at approximately 50,000 points spread over all streets of city. The obtained results ranged from 40 nSv.h -1 to 420 nSv.h -1 where the mean value was 112 nSv.h -1 . The spatial distribution of gamma exposure over the city is quite homogeneous with lowest and highest values in western and southern area, respectively. (author)

  10. Calculation of dose conversion factors for doses in the fingernails to organ doses at external gamma irradiation in air

    International Nuclear Information System (INIS)

    Khailov, A.M.; Ivannikov, A.I.; Skvortsov, V.G.; Stepanenko, V.F.; Orlenko, S.P.; Flood, A.B.; Williams, B.B.; Swartz, H.M.

    2015-01-01

    Absorbed doses to fingernails and organs were calculated for a set of homogenous external gamma-ray irradiation geometries in air. The doses were obtained by stochastic modeling of the ionizing particle transport (Monte Carlo method) for a mathematical human phantom with arms and hands placed loosely along the sides of the body. The resulting dose conversion factors for absorbed doses in fingernails can be used to assess the dose distribution and magnitude in practical dose reconstruction problems. For purposes of estimating dose in a large population exposed to radiation in order to triage people for treatment of acute radiation syndrome, the calculated data for a range of energies having a width of from 0.05 to 3.5 MeV were used to convert absorbed doses in fingernails to corresponding doses in organs and the whole body as well as the effective dose. Doses were assessed based on assumed rates of radioactive fallout at different time periods following a nuclear explosion. - Highlights: • Elemental composition and density of nails were determined. • MIRD-type mathematical human phantom with arms and hands was created. • Organ doses and doses to nails were calculated for external photon exposure in air. • Effective dose and nail doses values are close for rotational and soil surface exposures.

  11. Gamma-ray dose-rates to human tissues from natural external sources in Great Britain

    International Nuclear Information System (INIS)

    Spiers, F.W.

    1960-01-01

    The information on environmental gamma radiation given in the last report (Spiers, 1956) was limited by the small amount of experimental data then available. Considerably more information has been accumulated since then and a summary has been published in the Report of the United Nations Scientific Committee on te Effects of Atomic Radiation 1958). The data reported from Austria, France, Sweden and the U.S.A. show that in general dose-rates out-of-doors range from about 0 mrads per year over sedimentary rocks to about 200 mrads per year in granite districts. In houses a similar range of doserates is indicated, the rates in individual houses depending upon the nature of the building materials. In some parts of the world, however, very much higher dose-rates have been observed. On the extensive area of monazite sand in the Kerala State of India dose-rates of up to 4000 mrads per year have been recorded and the mean dose-rate for 10 villages with a total population of 52,000 has been estimated to be 1270 mrads per year. Mean dose-rates of 500 and 1600 mrads per year have also been reported from two localities in Brazil

  12. Gamma-ray dose-rates to human tissues from natural external sources in Great Britain

    Energy Technology Data Exchange (ETDEWEB)

    Spiers, F W

    1960-12-01

    The information on environmental gamma radiation given in the last report (Spiers, 1956) was limited by the small amount of experimental data then available. Considerably more information has been accumulated since then and a summary has been published in the Report of the United Nations Scientific Committee on te Effects of Atomic Radiation 1958). The data reported from Austria, France, Sweden and the U.S.A. show that in general dose-rates out-of-doors range from about 0 mrads per year over sedimentary rocks to about 200 mrads per year in granite districts. In houses a similar range of doserates is indicated, the rates in individual houses depending upon the nature of the building materials. In some parts of the world, however, very much higher dose-rates have been observed. On the extensive area of monazite sand in the Kerala State of India dose-rates of up to 4000 mrads per year have been recorded and the mean dose-rate for 10 villages with a total population of 52,000 has been estimated to be 1270 mrads per year. Mean dose-rates of 500 and 1600 mrads per year have also been reported from two localities in Brazil.

  13. Estimation of remote effects in blood animals after combination action of external acute gamma-radiation and EHF-range radiowave

    International Nuclear Information System (INIS)

    Chudakova, O.V.; Nikolaevich, L.N.

    2004-01-01

    In work the experimental data on study of influence combination action of external acute gamma-radiation and EMR SHF-range on hematological status of animals. It is revealed the stimulating effect of action of EMR on irradiated organism. (Authors)

  14. Tests for removal of Co-60 and Eu-154 from irradiated graphite in the TRIGA Reactor

    International Nuclear Information System (INIS)

    Arsene, Carmen

    2009-01-01

    The irradiated graphite in Romania is mainly generated in the thermal columns of TRIGA and WWER-S research reactors (about 9 tones). It was found that the radionuclide content of the graphite irradiated in the TRIGA research reactor is mainly due to C-14 (103 Bq/g), Eu-152 (600-700 Bq/g) and Co-60 (130-150 Bq/g) and low amounts of Eu-154 and Cs-137, depending on location in the thermal column and on irradiation history. In order to minimize the waste inventory and volume in view of their final disposal, in the present paper we show the results of experiments performed for developing and optimizing methods for the chemical decontamination of the irradiated graphite. These procedures are based on strong alkaline solutions for Eu-152 and strong acid solutions for Co-60. The influence of the process parameters on the decontamination factor is investigated. (authors)

  15. Effect of Rain Acidity Upon Mobility of Cs-134 and Co-60 in Soil

    International Nuclear Information System (INIS)

    Ruangchuay, S.; Harvey, N.W.; Sriyotha, P.

    1998-01-01

    This research was aimed to study the effects of groundwater and acid rain upon the mobility of radionuclides (Cs-134 and Co-60) in contaminated top soil. Clay soil was homogeneously packed in columns with dimension φ.12.5 cm. * 50 cm.. At the top 5 cm. of the columns, soil contaminated with radionuclides was added with the same consistency. Column were kept standing for 4 months in an artificial water table kept at 3 cm. from the bottom. During this period artificial acid rain with pH3, 4.5 and 6 was applied weekly at the top. Soil samples were taken every 30 days for examination of total and extracable radioactivity. It was shown that with the aide of the rain radionuclide movement down the profile was greater, with Co-60 > Cs-134. However acidity of the rain shown no effect on their movement

  16. Absorbed dose modeled for a liquid circulating around a Co-60 irradiator

    International Nuclear Information System (INIS)

    Mangussi, J.

    2013-01-01

    A model for the distribution of the absorbed dose in a volume of liquid circulating into an active tank containing a Co-60 irradiator is presented. The absorbed dose, the stir process and the liquid recirculation into the active tank are modeled. The absorbed dose for different fractions of the volume is calculated. The necessary irradiation times for the achievement of the required absorbed dose are evaluated. (author)

  17. 東海研究所Co-60照射室25年史

    OpenAIRE

    長山 尚; 大久保 隆; 出井 数彦; 辻村 重男

    1984-01-01

    東海研究所・Co-60照射室は昭和33年に完成以来今日に至るまで、所内外の多様なガンマ線照射要求に応え、幅広い照射サービスを実施して来た。この間、建屋、設備の改造修理が数多く行われ、またCo-60線源も数回補充増強された。本報告は、(1)ケーブの遮断の補強、放射線遮断窓の保守交換、線源貯蔵孔の変更など、ケーブ関係設備の保守改造、(2)線源の仕様、組立作業、(3)主要実験装置の概略、(4)建屋増改築、(5)所内外利用者の研究テーマ、試験テーマの推移、について述べたもので、Co-60照射室の25年間に至る活動の記録である。...

  18. EXTERNAL COMPTON SCATTERING IN BLAZAR JETS AND THE LOCATION OF THE GAMMA-RAY EMITTING REGION

    Energy Technology Data Exchange (ETDEWEB)

    Finke, Justin D., E-mail: justin.finke@nrl.navy.mil [U.S. Naval Research Laboratory, Code 7653, 4555 Overlook Ave. SW, Washington, DC, 20375-5352 (United States)

    2016-10-20

    I study the location of the γ -ray emission in blazar jets by creating a Compton-scattering approximation that is valid for all anisotropic radiation fields in the Thomson through Klein–Nishina regimes, is highly accurate, and can speed up numerical calculations by up to a factor of ∼10. I apply this approximation to synchrotron self-Compton, external Compton scattering of photons from the accretion disk, broad line region (BLR), and dust torus. I use a stratified BLR model and include detailed Compton-scattering calculations of a spherical and flattened BLR. I create two dust torus models, one where the torus is an annulus and one where it is an extended disk. I present detailed calculations of the photoabsorption optical depth using my detailed BLR and dust torus models, including the full angle dependence. I apply these calculations to the emission from a relativistically moving blob traveling through these radiation fields. The ratio of γ -ray to optical flux produces a predictable pattern that could help locate the γ -ray emission region. I show that the bright flare from 3C 454.3 in 2010 November detected by the Fermi Large Area Telescope is unlikely to originate from a single blob inside the BLR. This is because it moves outside the BLR in a time shorter than the flare duration, although emission by multiple blobs inside the BLR is possible. Also, γ -rays are unlikely to originate from outside of the BLR, due to the scattering of photons from an extended dust torus, since the cooling timescale would be too long to explain the observed short variability.

  19. Doses of external exposure in Jordan house due to gamma-emitting natural radionuclides in building materials.

    Science.gov (United States)

    Al-Jundi, J; Ulanovsky, A; Pröhl, G

    2009-10-01

    The use of building materials containing naturally occurring radionuclides as (40)K, (232)Th, and (238)U and their progeny results in external exposures of the residents of such buildings. In the present study, indoor dose rates for a typical Jordan concrete room are calculated using Monte Carlo method. Uniform chemical composition of the walls, floor and ceiling as well as uniform mass concentrations of the radionuclides in walls, floor and ceiling are assumed. Using activity concentrations of natural radionuclides typical for the Jordan houses and assuming them to be in secular equilibrium with their progeny, the maximum annual effective doses are estimated to be 0.16, 0.12 and 0.22 mSv a(-1) for (40)K, (232)Th- and (238)U-series, respectively. In a total, the maximum annual effective indoor dose due to external gamma-radiation is 0.50 mSv a(-1). Additionally, organ dose coefficients are calculated for all organs considered in ICRP Publication 74. Breast, skin and eye lenses have the maximum equivalent dose rate values due to indoor exposures caused by the natural radionuclides, while equivalent dose rates for uterus, colon (LLI) and small intestine are found to be the smallest. More specifically, organ dose rates (nSv a(-1)per Bq kg(-1)) vary from 0.044 to 0.060 for (40)K, from 0.44 to 0.60 for radionuclides from (238)U-series and from 0.60 to 0.81 for radionuclides from (232)Th-series. The obtained organ and effective dose conversion coefficients can be conveniently used in practical dose assessment tasks for the rooms of similar geometry and varying activity concentrations and local-specific occupancy factors.

  20. The HYLOCOMIUM SPLENDENS use for research of Ignalina NPP vicinity contamination by Cs 137 and Co 60

    International Nuclear Information System (INIS)

    Kiponas, D.; Marchiulenene, D.

    2002-01-01

    The superficial distribution of Cs 137 and Co 60 and specific activity of these radionuclides in Hylocomium splendens in Ignalina NPP vicinity was investigated. The increase of Cs 137 and Co 60 specific activity in Hylocomium splendens was linked with increasing of these radionuclides activity in atmospheric deposits

  1. Use of TL dosemeters for measuring doses of external gamma radiation in the vicinity of the Dukovany NPP

    International Nuclear Information System (INIS)

    Ohera, M.; Fiala, E.; Valasek, J.

    1992-01-01

    The results of measurement of the photon dose equivalent from external gamma radiation in the surroundings of the Dukovany nuclear power plant are given for 20 sites in southern Moravia over the 1984-1990 period, i.e., one year before starting up the plant and 6 years of its operation. CaSO 4 :Dy TL dosemeters were used, applying filtration with 0.5 mm Pb and 0.2 mm Pb + 0.6 mm Sn. Since 1989, the towns along the borders with Austria (Znojmo, Vranov, Mikulov) have been included, along with the Brno, Trebic, Zakrany, Ivancice and Jaromerice sites, into the national monitoring TL dosimetric network. The elevated doses at some sites come from the bedrock and are not caused by the operation of the plant. The effect of the Chernobyl accident on the dosemeter response is also evaluated. Comparison of the data prior to the Dukovany plant start-up (1984) and during the operation (1985-1990) give evidence that the operation of the power plant did not bring about any increase in the values monitored. (Z.S.). 3 tabs., 8 figs., 9 refs

  2. Tolerance of mango cv. ´Ataulfo' to irradiation with Co-60 vs. hydrothermal phytosanitary treatment

    Science.gov (United States)

    Gómez-Simuta, Y.; Hernández, Emilio; Aceituno-Medina, Marysol; Liedo, Pablo; Escobar-López, Arseny; Montoya, Pablo; Bravo, Bigail; Hallman, Guy J.; Bustos, M. Emilia; Toledo, Jorge

    2017-10-01

    The use of ionizing irradiation or the use of hot water treatment (HWT) has been demonstrated as a successful commercial phytosanitary treatment during the past two decades. Several countries currently use this technology for commercial treatments to meet plant quarantine requirements. However, hydrothermal treatment has been found to significantly affect the firmness of ;Ataulfo; mango fruit, the susceptibility to damage by cold and it also accelerates their maturation. In this study, we focused on the effect of irradiation doses on the sensorial quality and the physiochemical properties of mango cv ;Ataulfo; compared with the traditional hot water treatment. We found that doses of 150 Gy and 300 Gy of gamma radiation can be applied successfully as well as the hot water treatment. There was no significant difference in between irradiation treatments in terms of weight loss, external and internal color, pH, soluble solids, titratable acidity and firmness, and consumer's acceptance. There was no adverse effect of color appearance, odor and flavor, indicating that consumers will have the willingness to buy and consume irradiated mangoes. Irradiation of mangoes can be a successful post-harvest treatment as an alternative to the hot water treatment.

  3. Dose mapping using MCNP code and experiment for SVST-Co-60/B irradiator in Vietnam.

    Science.gov (United States)

    Tran, Van Hung; Tran, Khac An

    2010-06-01

    By using MCNP code and ethanol-chlorobenzene (ECB) dosimeters the simulations and measurements of absorbed dose distribution in a tote-box of the Cobalt-60 irradiator, SVST-Co60/B at VINAGAMMA have been done. Based on the results Dose Uniformity Ratios (DUR), positions and values of minimum and maximum dose extremes in a tote-box, and efficiency of the irradiator for the different dummy densities have been gained. There is a good agreement between simulation and experimental results in comparison and they have valuable meanings for operation of the irradiator. Copyright 2010 Elsevier Ltd. All rights reserved.

  4. A gonadal shield with appropriate wall thicknesses for Co-60-teletherapy

    International Nuclear Information System (INIS)

    Kahlhoefer, J.

    1982-01-01

    A gonadal shield for men has been designed especially for use in Co-60-teletherapy of ventral fields in supine position. It has been made by simple means in the clinical workshop. The thickness of the top, sides, and botton are equal to about 3 half value layers for scattered radiation incident in the respective directions. Radiation dose rate to the testicles during irradiation of a large abdominal field ('inverted Y') was measured in a phantom and was found to be 7.1% of tumour dose rate without shield and 0.9% with gonadal shield. (orig.) [de

  5. Suppressing effects of glucan on micronuclei induced by Co60 in mice

    International Nuclear Information System (INIS)

    Chorvatovicova, D.

    1991-01-01

    The effects of glucan on the frequency of micronuclei in polychromatic erythrocytes of A/Ph mouse bone marrow induced by Co 60 irradiation were examined. Suppressing effect of three glucan derivatives was statistically significant (P 3 substituent (DS 0.89). Intraperitoneal application of glucan has to be done earlier than one hour after irradiation. The suppressive effects of glucans can be explained by their ability to trap OH radicals and so decrease the clastogenic effect of irradiation. The results may be useful for therapeutic application of glucan with radiation therapy. (orig.) [de

  6. Monte Carlo based demonstration of sufficiently dimensioned shielding for a Co-60 testing facility

    International Nuclear Information System (INIS)

    Wind, Michael; Beck, Peter; Latocha, Marcin

    2015-01-01

    The electrical properties of electronic equipment can be changed in an ionized radiation field. The knowledge of these changes is necessary for applications in space, in air traffic and nuclear medicine. Experimental tests will be performed in Co-60 radiation fields in the irradiation facility (TEC facility) of the Seibersdorf Labor GmbH that is in construction. The contribution deals with a simulation that is aimed to calculate the local dose rate within and outside the building for demonstration of sufficient dimensioning of the shielding in compliance with the legal dose rate limits.

  7. Verification of Treatment Planning System (TPS) on Beam Axis of Co-60 Teletherapy

    International Nuclear Information System (INIS)

    Nunung-Nuraeni; Budhy-Kurniawan; Purwanto; Sugiyantari; Heru-Prasetio; Nasukha

    2001-01-01

    Cancer diseases up to now can be able to be treated by using surgery, chemotherapy and radiotherapy. The need of high level precision and accuracy on radiation dose are very important task. One of task is verification of Treatment Planning System (Tps) to the treatment of patients. The research has been done to verify Tps on beam exis of teletherapy Co-60. Result found that the different between Tps and measurements are about -2.682 % to 1.918% for simple geometry and homogeneous material, 5.278 % to 4.990 % for complex geometry, and -3.202 % to -2.090 % for more complex geometry. (author)

  8. Effect of Co60 irradiation on capillary changes in the rat periosteum

    International Nuclear Information System (INIS)

    Hachiya, Hiroshi

    1992-01-01

    There exist considerable literatures on the vascular changes by tolerance dose or over tolerance dose irradiation, but little work has been done to study the effect of under tolerance dose irradiation on capillary changes. The purpose of this study was to observe capillary changes in the periosteum of rats after Co 60 irradiation. The vascularity of the periosteum was observed with vascular resin casts and scanning electron microscope at 3 days to 30 weeks after the heads were exposed to 10 Gy or 20 Gy of Co 60 γ ray. The results were as follows: In rats irradiated with 10 Gy, leakage of resin from the fine blood vessels was observed at 3 weeks. Decrease in the diameter of small blood vessels and decrease of capillary networks were observed at 5 weeks. These changes improved at 7 weeks. In rats irradiated with 20 Gy, leakage of resin and decrease in the diameter of the small blood vessels were observed at 2 weeks. The number of small blood vessels was decreased at 4 weeks. These changes improved at 7 weeks. (author) 60 refs

  9. Evaluation of the Kerma at the entrance of the labyrin thin in facilities with Co-60 HDR brachytherapy

    International Nuclear Information System (INIS)

    Pujades, M. C.; Granero, D.; Ballester, F.; Perez-Calatayud, J.; Vijande, J.

    2013-01-01

    The purpose of this study is to evaluate the kerma's collision at the entrance of the labyrinth adapting the methodology of the NCRP-151 to a bunker of brachytherapy with Co-60, similar to the one carried out in a previous work with HDR Ir-192. To validate the result is simulated using techniques Monte Carlo (MC) two typical designs of HDR with Co-60 bunker. (Author)

  10. Photon beam modelling with Pinnacle3 Treatment Planning System for a Rokus M Co-60 Machine

    International Nuclear Information System (INIS)

    Dulcescu, Mihaela; Murgulet Cristian

    2008-01-01

    The basic relationships of the convolution/superposition dose calculation technique are reviewed, and a modelling technique that can be used for obtaining a satisfactory beam model for a commercially available convolution/superposition-based treatment planning system is described. A fluence energy spectrum for a Co-60 treatment machine obtained from a Monte Carlo simulation was used for modelling the fluence spectrum for a Rokus M machine. In order to achieve this model we measured the depth dose distribution and the dose profiles with a Wellhofer dosimetry system. The primary fluence was iteratively modelled by comparing the computed depth dose curves and beam profiles with the depth dose curves and crossbeam profiles measured in a water phantom. The objective of beam modelling is to build a model of the primary fluence that the patient is exposed to, which can then be used for the calculation of the dose deposited in the patient. (authors)

  11. Preliminary design of betavoltaic battery using Co-60 and Pm-147 with GaAs substrate

    Energy Technology Data Exchange (ETDEWEB)

    Waris, A., E-mail: awaris@fi.itb.ac.id; Basar, K. [Nuclear Physics & Biophysics Research Division, Department of Physics, Faculty of Mathematics and Natural Sciences, Institut Teknologi Bandung, Jl. Ganesa 10 Bandung 40132 (Indonesia); Kusumawati, Y.; Alfarobi, A. S.; Aji, I. K. [Department of Physics, Faculty of Mathematics and Natural Sciences, Institut Teknologi Bandung, Jl. Ganesa 10 Bandung 40132 (Indonesia)

    2016-03-11

    Battery is very important for the present daily life, especially for portable devices. The longer utilization time the better performance of battery. Betavoltaic battery is a device that converts energy from beta decays of radioactive nuclide into electric current. One of merits of the later battery is the life time that can be more than ten years without recharging. To develop the betavoltaic battery for energy source of portable devices we have performed a preliminary simulation design of betavoltaic battery using Pm-147 and Co-60 a beta emitter radionuclides with n-GaAs substrate. From the results we found that the combination of Pm-147 with n-GaAs substrate results in 9.0% of efficiency and higher output current compared to references.

  12. Preliminary design of betavoltaic battery using Co-60 and Pm-147 with GaAs substrate

    International Nuclear Information System (INIS)

    Waris, A.; Basar, K.; Kusumawati, Y.; Alfarobi, A. S.; Aji, I. K.

    2016-01-01

    Battery is very important for the present daily life, especially for portable devices. The longer utilization time the better performance of battery. Betavoltaic battery is a device that converts energy from beta decays of radioactive nuclide into electric current. One of merits of the later battery is the life time that can be more than ten years without recharging. To develop the betavoltaic battery for energy source of portable devices we have performed a preliminary simulation design of betavoltaic battery using Pm-147 and Co-60 a beta emitter radionuclides with n-GaAs substrate. From the results we found that the combination of Pm-147 with n-GaAs substrate results in 9.0% of efficiency and higher output current compared to references.

  13. Assessment Of Co60 Industrial Irradiators According To Basic Design Principles

    Directory of Open Access Journals (Sweden)

    El-Sayed Mohamed El Refaie

    2017-04-01

    Full Text Available Ensuring safe and easy operation providing relative uniform dose in the product and maximizing radiation utilization are the basic design principles for each Co60 industrial irradiator to maintain radiation safety. The study shows an assessment for four industrial irradiators to determine which active results were been maintained by using basic design principles. Different designs elements of the chosen irradiators have been illustrated and studied. The study shows that IRASM and ROBO industrial irradiators satisfy all basic design principles. IAEA-NR3772 irradiator maintains only two of the three basic design principles due to rotating door. Brevion irradiator satisfies only the principle of relative uniform radiation dose in product. Without affecting radiation safety this study proposes a new design of the irradiator to maximize energy utilization by adding a new track for low density products and also a static irradiation for cultural heritage beside the main track of high density products.

  14. SIMULATIONS OF GAMMA-RAY BURST JETS IN A STRATIFIED EXTERNAL MEDIUM: DYNAMICS, AFTERGLOW LIGHT CURVES, JET BREAKS, AND RADIO CALORIMETRY

    Energy Technology Data Exchange (ETDEWEB)

    De Colle, Fabio; Ramirez-Ruiz, Enrico [TASC, Department of Astronomy and Astrophysics, University of California, Santa Cruz, CA 95064 (United States); Granot, Jonathan [Racah Institute of Physics, The Hebrew University, Jerusalem 91904 (Israel); Lopez-Camara, Diego [Instituto de Ciencias Nucleares, Universidad Nacional Autonoma de Mexico, Ap. 70-543, 04510 D.F. (Mexico)

    2012-05-20

    The dynamics of gamma-ray burst (GRB) jets during the afterglow phase is most reliably and accurately modeled using hydrodynamic simulations. All published simulations so far, however, have considered only a uniform external medium, while a stratified external medium is expected around long duration GRB progenitors. Here, we present simulations of the dynamics of GRB jets and the resulting afterglow emission for both uniform and stratified external media with {rho}{sub ext}{proportional_to}r{sup -k} for k = 0, 1, 2. The simulations are performed in two dimensions using the special relativistic version of the Mezcal code. Common to all calculations is the initiation of the GRB jet as a conical wedge of half-opening angle {theta}{sub 0} = 0.2 whose radial profile is taken from the self-similar Blandford-McKee solution. The dynamics for stratified external media (k = 1, 2) are broadly similar to those derived for expansion into a uniform external medium (k = 0). The jet half-opening angle is observed to start increasing logarithmically with time (or radius) once the Lorentz factor {Gamma} drops below {theta}{sup -1}{sub 0}. For larger k values, however, the lateral expansion is faster at early times (when {Gamma} > {theta}{sup -1}{sub 0}) and slower at late times with the jet expansion becoming Newtonian and slowly approaching spherical symmetry over progressively longer timescales. We find that, contrary to analytic expectations, there is a reasonably sharp jet break in the light curve for k = 2 (a wind-like external medium), although the shape of the break is affected more by the viewing angle (for {theta}{sub obs} {<=} {theta}{sub 0}) than by the slope of the external density profile (for 0 {<=} k {<=} 2). Steeper density profiles (i.e., increasing k values) are found to produce more gradual jet breaks while larger viewing angles cause smoother and later appearing jet breaks. The counterjet becomes visible as it becomes sub-relativistic, and for k = 0 this results

  15. Treatment plan quality of tri-Co-60 MR-IGRT system in comparison with that of VMAT

    Energy Technology Data Exchange (ETDEWEB)

    Park, Jong Min; Park, So Yeon; Kim, Jung In [Dept. of Nuclear Engineering, Seoul National University Hospital, Seoul (Korea, Republic of); Kim, Hak Jae; Wu, Hong Gyun [Dept. of Nuclear Engineering, Seoul National University College of Medicine, Seoul (Korea, Republic of)

    2016-04-15

    The ViewRay{sup TM} system combines a 0.35-T MR imaging system and a radiation therapy system using a total of three Co-60 sources. It can perform static intensity-modulated radiation therapy (IMRT) with multi-leaf collimators (MLCs) with leaf widths of 1.05 cm at the plane of isocenter, at source to axis distance (SAD) of 105 cm. Since the tri-Co-60 MR-IGRT system can acquire near-real-time cine sagittal MR images during treatment, automated respiratory gating can be performed based on these cine images, thus, the target margins for lung stereotactic ablative radiotherapy (SABR) could be reduced considerably by comparison with the internal tarvet volume (ITV) approach. we compared lung SABR treatment plans of the tri-Co-60 MR-IGRT system with gross tumor volume (GTV) to those of volumetric modulated arc therapy (VMAT) using TrueBeam STx™ (Varian Medical Systems, Palo Alto, CA) with ITV in this study. The plan quality of the target volume of the VMAT with ITV was better than that of the GTV-based tri-Co-60 MR-IGRT for lung SABR. No significant differences for OARs were observed between the tri-Co-60 MR-IGRT and VMAT. However, the plan quality of the tri-Co-60 MR-IGRT system was clinically acceptable. Despite the relatively poor plan quality of the tri-Co-60 MR-IGRT system, it still has the advantage of real-time monitoring of tumor motion during treatment.

  16. Calculation of uncertainties in the protocol of dosimetry for Co 60 beams in Radiotherapy; Calculo de incertidumbres en el protocolo de dosimetria para haces de Co 60 en Radioterapia

    Energy Technology Data Exchange (ETDEWEB)

    Velazquez M, S.; Carrera M, F.; Sanchez S, J. [Hospital Juan Ramon Jimenez, Ronda Norte s/n 21005 Huelva (Spain)

    1998-12-31

    The objective in this work is to show how the uncertainty is possible to know in the determination of the absorbed dose in Co 60 photon beams and to establish in a rational form, tolerance levels for this. It is took as base the spanish protocol of dosimetry in Radiotherapy. We have been centered in a Co 60 beam. We utilized the statistical theory of little samples. We allowed to suggest a new approach about the treatment of the tolerance levels and the uncertainty of the measurement. After two years of experience in the practical hospitable application we have gotten to put around 1 % uncertainty in the absolute dosimetry of the Co 60 beam. The presented protocol allows to execute the accuracy requirements in the determination of absorbed doses. (Author)

  17. Dose distribution in the area of the operative cicatrice and the problem of local reccurences during postoperative external beam gamma therapy of breast cancer

    International Nuclear Information System (INIS)

    Todorov, Y.; Ivanova, K.; Penchev, V.

    1982-01-01

    Five-year experience is recorded with treatment of 503 patients with breast cancer, who received postoperative external beam gamma therapy, and the developement of local reccurences. Results are reported of dosimetric studies in the irradiated area, especially the thoracic wall, where total focal doses of 50 had been realized. The clinical results of treatment are discussed on this basis. Comparison is made with data available in the literature on the incidence, localization and time of development of local reccurences and the methods of treatment of the basic disease. The need of postoperative radiation treatment, particularly in the later stages of the disease, is pointed out. (authors)

  18. Gamma radiation effects with Co-60 for radurization and radicidation in fillets and fish eggs of the Merluccius Merluccius hubbsi

    International Nuclear Information System (INIS)

    Valdes Rodriguez, E

    1982-01-01

    Part I: theoretical considerations: introduction, methodology in the processing of foods, physical-chemical action of the radiations, microbiologycal aspects, action of the radiation and of the drops temperatures, physiologic aspects, changes taken place in the stored fish, changes taken place by the ionizing radiation in the biological structures. II: Experimental work, generalities of experimental work, objectives, materials and methods of the experimental work, presentation of results, conclusions

  19. An Experimental Study on the Effects of Co-60 Irradiation on the Rat Tongue Tissue

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Seon Kee; Lee, Sang Rae [Dept. of Oral Radiology, College of Dentistry, Kyung Hee University, Seoul (Korea, Republic of)

    1990-02-15

    It is known that radiation therapy is a kind of treatment choices of the maxillofacial tumors. This study is designed to investigate the effects of irradiation on rat's tongue tissues as functional tissues which relate to taste, mastication, and pronunciation. 88 rats (Sprague Dawley branch, male) were divided into control group of 4 and experimental group of 84. Experimental group was singly exposed to Co-60 irradiation with 8, 13, 18 Gy in the head and neck region. Animals were sacrificed on 1 hour, 3 hours, 6 hours, 1 day, 3 days, 7 days, and 28 days after the irradiation. The specimens were observed by histopathological examination employing H-E stain and Van-Gieson stain. The results were follows; 1. The tongue tissue were severely swollen on the 1 hour after irradiation, but gradually decreased in course of time. 2. The basal cells of epithelium of tongue proliferated at initial stage of irradiation, but gradually decreased. The Keratin layer were gradually increased. 4. The tissue changes after irradiation were gradually increased by the degree of irradiation.

  20. Development of semi-empirical equations for In-water dose distribution using Co-60 beams

    International Nuclear Information System (INIS)

    Abdalla, Siddig Abdalla Talha

    2001-08-01

    Knowledge of absorbed dose distribution is essential for the management of cancer using Co-60 teletherapy. Since direct measurement of dose in patient is impossible, indirect assessments are always carried. In this study direct assessments in phantoms were taken for dose distribution data. Mainly we concentrated on central axis dose and isodose curves data, which are essential for treatment planning. We started by development of a semi-empirical method which uses a more restricted number of measurements and uses graphical relation to develop the dose distribution. This method was based on the decrement lines method which was introduced by Orchard (1964) to develop isodose curve. In the beginning the already developed percent depth dose, Pdd, equation was modified and used to plot the Pdd lines for randomly selected field sizes. After that the dose profiles at depths 5, 10, 15 and 20 cm for randomly selected field sizes were plotted from the direct measurement. Then with the help of the PDD's equation, an equation for the slope of decrement lines is developed. From this slope equation a relation that gives the off axial distance was found. Making use of these relations, the iso lines 80%, 50% and 20% were plotted for the field sizes: 6*6 cm 2 , 10*10 cm 2 and 18*18 cm 2 . Finally these plotted lines were compared to their correspondents from the manufacturer and those used in the hospital (Rick). (Author)

  1. Onset of behavioral effects in mice exposed to 10 Gy Co-60 radiation

    International Nuclear Information System (INIS)

    Maier, D.M.; Landauer, M.R.

    1990-01-01

    The effects of 10 Gray (Gy) Co-60 radiation on social behavior, locomotor activity, and body weight were assessed in individually housed male Swiss-Webster mice. In experiment 1, aggressive behavior was evaluated prior to irradiation and for 7 d postirradiation by placing an untreated intruder in the irradiated or sham-irradiated resident's home cage for 5 min. Offensive aggressive behavior was not affected significantly by radiation until day 7 postirradiation, when attack latency increased, the frequency and duration of fighting decreased, and the frequency of bites, lunges, and chases decreased. Untreated intruder mice paired with irradiated resident mice showed a decrease in the duration of defensive upright postures and a decrease in the frequency of defensive upright postures, squeaks, and escapes on day 7 postirradiation. In experiment 2, locomotor activity and body weight were monitored for 7 d postirradiation. Body weight was decreased in irradiated mice beginning 4 d postirradiation. Locomotor activity was suppressed in irradiated animals 90 min after irradiation and remained depressed throughout the 7-d testing period. 25 refs

  2. 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)

  3. Cardiovascular changes in atherosclerotic ApoE-deficient mice exposed to Co60 (γ radiation.

    Directory of Open Access Journals (Sweden)

    Prem Kumarathasan

    Full Text Available BACKGROUND: There is evidence for a role of ionizing radiation in cardiovascular diseases. The goal of this work was to identify changes in oxidative and nitrative stress pathways and the status of the endothelinergic system during progression of atherosclerosis in ApoE-deficient mice after single and repeated exposure to ionizing radiation. METHODS AND RESULTS: B6.129P2-ApoE tmlUnc mice on a low-fat diet were acutely exposed (whole body to Co60 (γ (single dose 0, 0.5, and 2 Gy at a dose rate of 36.32 cGy/min, or repeatedly (cumulative dose 0 and 2 Gy at a dose-rate of 0.1 cGy/min for 5 d/wk, over a period of 4 weeks. Biological endpoints were investigated after 3-6 months of recovery post-radiation. The nitrative stress marker 3-nitrotyrosine and the vasoregulator peptides endothelin-1 and endothelin-3 in plasma were increased (p<0.05 in a dose-dependent manner 3-6 months after acute or chronic exposure to radiation. The oxidative stress marker 8-isoprostane was not affected by radiation, while plasma 8-hydroxydeoxyguanosine and L-3,4-dihydroxyphenylalanine decreased (p<0.05 after treatment. At 2Gy radiation dose, serum cholesterol was increased (p = 0.008 relative to controls. Percent lesion area increased (p = 0.005 with age of animal, but not with radiation treatment. CONCLUSIONS: Our observations are consistent with persistent nitrative stress and activation of the endothelinergic system in ApoE-/- mice after low-level ionizing radiation exposures. These mechanisms are known factors in the progression of atherosclerosis and other cardiovascular diseases.

  4. Exclusive radiation therapy of endometrial carcinoma using HDR Co-60 and Cf-252 sources

    International Nuclear Information System (INIS)

    Inciura, A.; Janulionis, E.; Atkocius, V.

    2000-01-01

    Although the main treatment of endometrial cancer is surgery, the gross spread of carcinoma in pelvis, elderly age of the patients and serious therapeutical diseases do not allow to operate 20% of the patients. For these patients only radical treatment decision is the combined radiation therapy. However, using various modalities of combined radiotherapy, the treatment results are not satisfying: only 52% of patients survive 5 years. There was implemented a new method of combined radiotherapy, using a three-channel applicator with two-positional locating of HDR Co-60 radioactive sources (group I). A new method of brachytherapy for endometrial carcinoma using a HDR Cf 252 sources (group II) was implemented too. For group I the medium total dose of the point A was 77.6 Gy, point I - 69.6 Gy. point 2 - 84.2 Gy, point B - 52.6 Gy, For group II the medium total dose the points A, 3 and 4 was 50 iGy. For group I 1 year overaII survival rate was 85%, 3 year - 73%. The 3 year survival rate for stage I was 79%, for stage II - 89%, for stage III - 33%. 3 year survival for highly virulent tumours - 56% and for low virulent (adenocarcinoma) - 82% was statistically different. The loss of tumour differentiation correlated with the worse prognosis: 3 year survival for G1 and G2 tumours was 92%, for G3 - 45%. Low hemoglobin level was also associated with low survival rate: 2 year survival for Hb≥120g/l was 85% and Hb<120g/l - 23%. 1 year survival rate was 87%, 3 year - 66%, 5 year - 58% for group II, treated with Cf-252. Radiation complications occurred for 13.8% of the patients for group I and 6.2% for group II. Good survival rates and a small number of complications sufficiently proofed treatment method. (author)

  5. Quality of tri-Co-60 MR-IGRT treatment plans in comparison with VMAT treatment plans for spine SABR.

    Science.gov (United States)

    Choi, Chang Heon; Park, So-Yeon; Kim, Jung-In; Kim, Jin Ho; Kim, Kyubo; Carlson, Joel; Park, Jong Min

    2017-02-01

    To investigate the plan quality of tri-Co-60 intensity-modulated radiation therapy (IMRT) plans for spine stereotactic ablative radiotherapy (SABR). A total of 20 patients with spine metastasis were retrospectively selected. For each patient, a tri-Co-60 IMRT plan and a volumetric-modulated arc therapy (VMAT) plan were generated. The spinal cords were defined based on MR images for the tri-Co-60 IMRT, while isotropic 1-mm margins were added to the spinal cords for the VMAT plans. The VMAT plans were generated with 10-MV flattening filter-free photon beams of TrueBeam STx ™ (Varian Medical Systems, Palo Alto, CA), while the tri-Co-60 IMRT plans were generated with the ViewRay ™ system (ViewRay inc., Cleveland, OH). The initial prescription dose was 18 Gy (1 fraction). If the tolerance dose of the spinal cord was not met, the prescription dose was reduced until the spinal cord tolerance dose was satisfied. The mean dose to the target volumes, conformity index and homogeneity index of the VMAT and tri-Co-60 IMRT were 17.8 ± 0.8 vs 13.7 ± 3.9 Gy, 0.85 ± 0.20 vs 1.58 ± 1.29 and 0.09 ± 0.04 vs 0.24 ± 0.19, respectively. The integral doses and beam-on times were 16,570 ± 1768 vs 22,087 ± 2.986 Gy cm 3 and 3.95 ± 1.13 vs 48.82 ± 10.44 min, respectively. The tri-Co-60 IMRT seems inappropriate for spine SABR compared with VMAT. Advances in knowledge: For spine SABR, the tri-Co-60 IMRT is inappropriate owing to the large penumbra, large leaf width and low dose rate of the ViewRay system.

  6. TLD Postal service for quality audits of beams of Co-60 in reference conditions in Cuba

    International Nuclear Information System (INIS)

    Gutierrez L, S.; Walwyn S, G.; Alonso V, G.

    2006-01-01

    Purpose: To describe the methodology and experience of the Secondary Laboratory of Dosimetric Calibration of Cuba in the establishment of the TLD Postal Service for quality audits of beams of Co-60 in reference conditions. Materials and methods: Through the Coordinated Project of Research (Contract 10794) its was bought 200 solid thermoluminescent detectors of LiF: Mg, Ti (TLD-100) in micro bars form with dimensions of 6 x 1 x 1 mm and of the JR 1152F type manufactured in China. All these detectors were identified individually with a serial number on one of its faces, using a graphite fine sheet. Those detectors for its irradiation are introduced in cylindrical plastic capsules developed and used by the International Atomic Energy Agency (IAEA) in the Audit Postal Service of Dose IAEA/WHO, the capsules have one cavity equal to 3 mm for that is necessary to recover this cavity with a fine plastic tube so that the detectors remain immobile during the irradiation. The method used to determine the individual sensitivity of the thermoluminescent detectors is: to irradiate a detectors group (100 micro bars) 4 times in those same geometric conditions, with the same irradiation history and reading, then it is determine for each detector a sensitivity factor equal to the average of those readings obtained for the 4 irradiation cycles for each i detector among the average of all the reading values obtained during the 4 cycles. The thermoluminescent signal is obtained with a Harshaw 2000C/B reader manual. Results: The satisfactory results obtained in the verification of the calibration of the TLD system, using the reference irradiation service of the Seibersdorf Dosimetry Laboratory of the IAEA in three different years are shown. The results of the audits carried out to the different radiotherapy services of the country in different years are also presented. Conclusions: The experience with the detectors acquired in the project demonstrates that with an appropriate

  7. SIMULATIONS OF GAMMA-RAY BURST JETS IN A STRATIFIED EXTERNAL MEDIUM: DYNAMICS, AFTERGLOW LIGHT CURVES, JET BREAKS, AND RADIO CALORIMETRY

    International Nuclear Information System (INIS)

    De Colle, Fabio; Ramirez-Ruiz, Enrico; Granot, Jonathan; Lopez-Camara, Diego

    2012-01-01

    The dynamics of gamma-ray burst (GRB) jets during the afterglow phase is most reliably and accurately modeled using hydrodynamic simulations. All published simulations so far, however, have considered only a uniform external medium, while a stratified external medium is expected around long duration GRB progenitors. Here, we present simulations of the dynamics of GRB jets and the resulting afterglow emission for both uniform and stratified external media with ρ ext ∝r –k for k = 0, 1, 2. The simulations are performed in two dimensions using the special relativistic version of the Mezcal code. Common to all calculations is the initiation of the GRB jet as a conical wedge of half-opening angle θ 0 = 0.2 whose radial profile is taken from the self-similar Blandford-McKee solution. The dynamics for stratified external media (k = 1, 2) are broadly similar to those derived for expansion into a uniform external medium (k = 0). The jet half-opening angle is observed to start increasing logarithmically with time (or radius) once the Lorentz factor Γ drops below θ –1 0 . For larger k values, however, the lateral expansion is faster at early times (when Γ > θ –1 0 ) and slower at late times with the jet expansion becoming Newtonian and slowly approaching spherical symmetry over progressively longer timescales. We find that, contrary to analytic expectations, there is a reasonably sharp jet break in the light curve for k = 2 (a wind-like external medium), although the shape of the break is affected more by the viewing angle (for θ obs ≤ θ 0 ) than by the slope of the external density profile (for 0 ≤ k ≤ 2). Steeper density profiles (i.e., increasing k values) are found to produce more gradual jet breaks while larger viewing angles cause smoother and later appearing jet breaks. The counterjet becomes visible as it becomes sub-relativistic, and for k = 0 this results in a clear bump-like feature in the light curve. However, for larger k values the jet

  8. Simulations of Gamma-Ray Burst Jets in a Stratified External Medium: Dynamics, Afterglow Light Curves, Jet Breaks, and Radio Calorimetry

    Science.gov (United States)

    De Colle, Fabio; Ramirez-Ruiz, Enrico; Granot, Jonathan; Lopez-Camara, Diego

    2012-05-01

    The dynamics of gamma-ray burst (GRB) jets during the afterglow phase is most reliably and accurately modeled using hydrodynamic simulations. All published simulations so far, however, have considered only a uniform external medium, while a stratified external medium is expected around long duration GRB progenitors. Here, we present simulations of the dynamics of GRB jets and the resulting afterglow emission for both uniform and stratified external media with ρextvpropr -k for k = 0, 1, 2. The simulations are performed in two dimensions using the special relativistic version of the Mezcal code. Common to all calculations is the initiation of the GRB jet as a conical wedge of half-opening angle θ0 = 0.2 whose radial profile is taken from the self-similar Blandford-McKee solution. The dynamics for stratified external media (k = 1, 2) are broadly similar to those derived for expansion into a uniform external medium (k = 0). The jet half-opening angle is observed to start increasing logarithmically with time (or radius) once the Lorentz factor Γ drops below θ-1 0. For larger k values, however, the lateral expansion is faster at early times (when Γ > θ-1 0) and slower at late times with the jet expansion becoming Newtonian and slowly approaching spherical symmetry over progressively longer timescales. We find that, contrary to analytic expectations, there is a reasonably sharp jet break in the light curve for k = 2 (a wind-like external medium), although the shape of the break is affected more by the viewing angle (for θobs <= θ0) than by the slope of the external density profile (for 0 <= k <= 2). Steeper density profiles (i.e., increasing k values) are found to produce more gradual jet breaks while larger viewing angles cause smoother and later appearing jet breaks. The counterjet becomes visible as it becomes sub-relativistic, and for k = 0 this results in a clear bump-like feature in the light curve. However, for larger k values the jet decelerates more

  9. External gamma radiation monitoring in the environs of Kaiga Generating Station (KGS), using thermoluminescent dosimeters, during the period 1989-2003

    International Nuclear Information System (INIS)

    Basu, A.S.; Chougaonkar, M.P.; Mayya, Y.S.; Puranik, V.D.; Reji, T.K.; Ravi, P.M.; Hegde, A.G.

    2005-05-01

    This publication reports the results of external gamma radiation monitoring using Thermoluminescent Dosimeters (TLDs), in the environs of Kaiga Generating Station (KGS) during its preoperational survey between October 1989 and June 1998. The report also presents quarterly and annual values of air dose during the operational phase of the station between July 1998 and Dec. 2003 around the environmcnt of KGS. The results of TLD analysis, during the period October 1989-June 1998, indicate that the average annual air dose for the locations monitored, was 502± 91 μGy/a. The general background of the environs around Kaiga during the operational period, i.e. July 1998 and Dec. 2003, between 2.3 km. to 32km. has been found to be 509±74 μGy/a. The report discusses the methodology and different analyses carried out. (author)

  10. Evaluation of personal dose equivalent 'HP(d)' in a external individual monitoring system for X and gamma radiation

    International Nuclear Information System (INIS)

    Santoro, C.; Antonio Filho, J.; Santos, M.A.P.

    2007-01-01

    The good of individual monitoring for external radiation is the assessment of occupational exposure from X and γ radiations in order to assure that the radiological conditions of the workplace are acceptable, safe and satisfactory. The evaluation of radiations doses for workers must not exceed dose limits specified for workers, according to national regulatory agencies. Nowadays, there are two external monitoring systems in use, both based on ICRU definitions. In the conventional system, the workers doses are evaluated in terms of Hx. The personal dosimeter is worn over chest surface and it is calibrated in function of air kerma. In the new system, the workers doses are evaluated in terms of HP(d) and the personal dosimeter is calibrated in function of phantom doses. The aim of this paper is to adapt an external dosimetry laboratory (based on photographic dosimetry) to evaluate the personal dosimeters in terms of HP(d). In this way, a simple methodology, based on linear programming, was utilized. In this adaptation, calibration curves were obtained for radiation qualities (W and N series) described by International Organization for Standardization (ISO 4037-1, 1995). These calibration curves offer a better accuracy on dose determinations and energy below 140 keV, improving the quality of service rendered the society. (author)

  11. Effect of γ-rays Co60 on the fermentation activity of Saccharomyces Vini

    International Nuclear Information System (INIS)

    Talipova, Sh.; Gulyamova, N.; Balasanyan, I.A.

    1978-01-01

    The fermentation activity of the local strains of yeast Saccharomyces vini, irradiated with the doses of 150-200 Krad of Co gamma-rays is studied. The strains effective for viniculture have been selected. It is noted that in irradiated yeast at the dose of 200 krad fermentation activity is enhanced, i.e. the rate and the energy of fermentation are increased. It has been found that irradiated yeast strains will completely ferment grape 24 hours earlier than in the control group. Wine prepared with irradiated strains by organoleptic indices is better than wine made with the Rkatsiteli-6 control industrial race

  12. The effect of gamma ray on growth and anatomy structure of garlic leaf (A. sativum L.)

    International Nuclear Information System (INIS)

    Sumiyarsih, S.; Aliudin

    1990-01-01

    This experiment was conducted in Experimental Garden Banaran, East Java. This experiment used Complete Randomized Design with 10 replications and 7 treatments as followed: garlic seeds were radiated by gamma Co 60, with dosage 0, 2, 4, 6, 8, 10, and 12 krad. The result of this experiment showed that radiated treatment of gamma Co 60 ray decreased growth percentage, plants became dwarf, root growth was short, and dosage 10 and 12 krad resulted in rotten root. Also radiation of gamma Co 60 decreased number of stomata and diameter of trachea became smaller

  13. COASTING EXTERNAL SHOCK IN WIND MEDIUM: AN ORIGIN FOR THE X-RAY PLATEAU DECAY COMPONENT IN SWIFT GAMMA-RAY BURST AFTERGLOWS

    Energy Technology Data Exchange (ETDEWEB)

    Shen Rongfeng; Matzner, Christopher D., E-mail: rfshen@astro.utoronto.ca, E-mail: matzner@astro.utoronto.ca [Department of Astronomy and Astrophysics, University of Toronto, Ontario M5S 3H4 (Canada)

    2012-01-01

    The plateaus observed in about one half of the early X-ray afterglows are the most puzzling feature in gamma-ray bursts (GRBs) detected by Swift. By analyzing the temporal and spectral indices of a large X-ray plateau sample, we find that 55% can be explained by external, forward shock synchrotron emission produced by a relativistic ejecta coasting in a {rho}{proportional_to}r{sup -2}, wind-like medium; no energy injection into the shock is needed. After the ejecta collects enough medium and transitions to the adiabatic, decelerating blast wave phase, it produces the post-plateau decay. For those bursts consistent with this model, we find an upper limit for the initial Lorentz factor of the ejecta, {Gamma}{sub 0} {<=} 46({epsilon}{sub e}/0.1){sup -0.24}({epsilon}{sub B}/0.01){sup 0.17}; the isotropic equivalent total ejecta energy is E{sub iso} {approx} 10{sup 53}({epsilon}{sub e}/0.1){sup -1.3}({epsilon}{sub B}/0.01){sup -0.09}(t{sub b} /10{sup 4} s) erg, where {epsilon}{sub e} and {epsilon}{sub B} are the fractions of the total energy at the shock downstream that are carried by electrons and the magnetic field, respectively, and t{sub b} is the end of the plateau. Our finding supports Wolf-Rayet stars as the progenitor stars of some GRBs. It raises intriguing questions about the origin of an intermediate-{Gamma}{sub 0} ejecta, which we speculate is connected to the GRB jet emergence from its host star. For the remaining 45% of the sample, the post-plateau decline is too rapid to be explained in the coasting-in-wind model, and energy injection appears to be required.

  14. Terrestrial gamma radioactivity levels and their corresponding external exposure of some soil samples from Elba protective area, Southeastern of Egypt

    International Nuclear Information System (INIS)

    El Arabi, A.M.; Ahmed, N.K.; Salahel Din, K.; Tykva, R.

    2007-01-01

    The study of natural gamma radioactivity was made to determine the concentrations of natural radionuclides in soil. Fifty four surface soil samples collected from three different cites (Wadi Daeeb , Wadi Sarara and Wadi Hodein) in Elba protective area, Southeastern of Egypt, were analyzed by Nal(Tl) detector to determine the activity concentrations of 226 Ra, 232 Th and 40 K. The mean activity concentration of radionuclides 226 Ra, 232 Th and 40 K are 20.9±1.6, 13.5 ± 1.1 and 477 ± 24 Bq kg -1 , respectively for Wadi Daeeb soils. The corresponding values for Wadi Sarara and Wadi Hodein soils are 27.8 ± 2.6, 17.8 ± 1.4 and 735.3 ± 29.8 Bq kg -1 and 20.3 ± 1.5, 12 ± 1 and 664.2 ± 20 Bq kg -1 , respectively. In order to evaluate the radiological hazard of the natural radioactivity, the radium equivalent activity (Ra eq ) and gamma activity concentration index (I) have been calculated and compared with the internationally approved values. The average annual effective doses outdoors, indoors and in total are estimated to be 0.046, 0.26 and 0.30 mSv, respectively for Wadi Daeeb soils. For Wadi Sarara and Wadi Hodein soils the corresponding values are 0.066, 0.37 and 0.44 mSv and 0.054, 0.30 and 0.36 mSv, respectively. Also the annual gonadal dose equivalent was calculated and found to be within safe limit

  15. The acid-base balance in women with neoplasmatic process of the genitals and the effect of Co60 therapy

    International Nuclear Information System (INIS)

    Tomaszkiewicz, T.; Markowska, J.; Glogowska, Z.; Simm, S.; Herwichowska, K.

    1980-01-01

    The acid-base balance parameters were determined in 34 women with neoplasmatic process in the genital organs (2 and 3 stage of development) before and after Co 60 therapy. Blood gasometery (capillary blood samples were drawn from the finger, ear-lobe and neoplasm-involved uterine cervix) served as basis for the study. After treatment an increase of the pCo 2 bicarbonates and base reserve values were noted in the capillary blood samples collected from the finger or ear-lobe and a decrease of the hydrogen ions concentration in the capillary blood drawn from the uterine cervix were met. The changes in electroneutrality of organism fluids were tested considering the treatment effects. After Co 60 treatment an increase of the pO 2 was demonstrated in both examined groups. (author)

  16. Cs-137 and Co-60 concentrations in water from the Savannah River and water-treatment plants downstream of SRP

    International Nuclear Information System (INIS)

    1983-01-01

    In preparation for restart of L-Reactor, a comprehensive environmental sampling and analysis program was initiated in March 1983 to determine Cs-137 concentrations in off-site water downstream from Savannah River Plant (SRP). Concentrations of Co-60 also are determined in this sampling and analysis program. This report summarizes the first three months of results. Cesium-137 concentrations are reported for finished water from the Beaufort-Jasper, Port Wentworth and North Augusta water treatment plants for weekly continuous samples during April through June 1983. The very low concentrations of cesium-137 in finished water from downstream water treatment plants showed significant changes during this time. The changes in concentration occurred smoothly and correlate with changes in river flow. No changes in concentration during April through June can be attributed to L-Reactor's only cold water test which occurred June 8 and 9. No Co-60 was observed in any samples

  17. Fireproofing and heat insulating performance improvement of EG/ATH modified intumescent flame retardant coating treated under Co-60 radiation

    Science.gov (United States)

    Zhang, Yuehong; Luan, Weiling; Jiang, Tao

    2017-12-01

    New intumescent flame retardant (IFR) coatings with different fire retardants were prepared in this paper. Expandable graphite (EG) and Aluminium hydroxide (ATH) were respectively added into the conventional IFR coating system, which included ammonium polyphosphate (APP) / pentaerythritol (PER) / melamine (MEL). The fireproofing time and heat insulating properties of the additives acted as fire retardants were investigated via thermogravimetry analysis (TGA) and fire resistance test of homemade big panel test. The morphology of the char layer structure was achieved by scanning electron microscopy (SEM). The highlight of the paper was that the coating samples were pretreated under Co-60 radiation. The influence of radiation on the fire resistance time and char layer height was investigated. The results showed that the prepared IFR coatings can be used in Co-60 radiation for more than 90 min when encountering fire. It would be a reference for radiation shielding in nuclear environment.

  18. Effect of gama irradiation (Co60 in the control of Enterococci spp. and Escherichia coli in chilled chicken (Gallus gallus heart

    Directory of Open Access Journals (Sweden)

    Marta Maria Braga Batista Soares Xavier

    2016-09-01

    Full Text Available The present study aimed to evaluate the efficiency of the irradiation process in the control of Enterococci spp. and Escherichia coli in chilled chicken heart samples acquired in an industry located in the West Zone of Rio de Janeiro, Brazil, using irradiation doses of 1.5 kGy, 3, 0 kGy and 4.5 kGy. These microorganisms are related to fecal contamination, and are indicators of the sanitary processing conditions of the foodstuffs. The bacteriological analyses were conducted applying the methodologies and standards recommended by Brazilian norms resolution no. 12 (BRASIL, 2001 and instruction no. 62 (BRASIL, 2003 Regarding Escherichia coli, no statistically significant difference among the four groups (control, 1.5 kGy, 3.0 kGy and 4.5 kGy was observed (p> 0.05. The Most Probable Number (MPN for Enterococci spp. was not proven in the investigated samples. Thus, the Co60 gamma irradiation process was effective in eliminating Escherichia coli, and the lowest dose, of 1.5 kGy, was enough to abolish this enteropathogen from the evaluated samples.

  19. Predicting corrosion of 316L stainless steel capsule by low level radioactive wastes (Am-241 and Co-60) in underground repository

    International Nuclear Information System (INIS)

    Nunoo, R.

    2013-07-01

    Most of radioactive wastes in Ghana are of low level in activity, (i.e LLRW) and are currently kept under lock in a secured room. The proposed plan by the Ghana Atomic Energy Commission is to seal the LLRW In 316L stainless steel disposal capsule for borehole repository. The research presented in this thesis was aimed at predicting the rate of both uniform and pitting corrosion of the 316L stainless steel disposal capsule by LLRW that will be kept in the capsule as a function of temperature, PH and chloride concentration for a period of up to 1000 years of disposal. The prediction analysis was based on the point defect deterministic model which assumed Schottky defects as the defect of the oxide formed on the surfaces of the disposal capsule. Faradays law and Fick first law of diffusion were used to determine the current across the internal and external surfaces of the capsule used to predict the uniform corrosion rate and corrosion loss of the 316L stainless steel disposal capsule. By imposing chlorine on the external environment of the disposal capsule, pit growth rate and pit depth of capsule were also predicted over a period of 1000 years. The capsule containing disused Am-241 source at activity level of 1.67×10 3 Bq had an average uniform corrosion rate of 3.65×10 -7 m/year and average pit growth rate of 1.79×10 -6 m/year while the corrosion rate and pit growth rate of the capsule containing disused Co-60 with activity level of 2.78×10 8 Bq were 6.9×10 -7 m/year and 2.1×10 -6 m/year respectively at PH value of 8 and repository temperature of 75°C and chloride concentration of 0.5 M. The uniform corrosion rate indicated that at PH=8 and T=75°C, 80.04% of the disposal capsule containing disused Am-241 would remain whiles 62.34% of that containing Co-60 disused source would remain after 1000 years when undergoing uniform corrosion, and an arbitrary position on the disposal capsule will have a pit depth of 1.98×10 -3 m after 100 years. Hence the integrity

  20. Broad band simulation of Gamma Ray Bursts (GRB) prompt emission in presence of an external magnetic field

    Science.gov (United States)

    Ziaeepour, Houri; Gardner, Brian

    2011-12-01

    The origin of prompt emission in GRBs is not yet well understood. The simplest and most popular model is Synchrotron Self-Compton (SSC) emission produced by internal shocks inside an ultra-relativistic jet. However, recent observations of a delayed high energy component by the Fermi-LAT instrument have encouraged alternative models. Here we use a recently developed formulation of relativistic shocks for GRBs to simulate light curves and spectra of synchrotron and self-Compton emissions in the framework of internal shock model. This model takes into account the evolution of quantities such as densities of colliding shells, and fraction of kinetic energy transferred to electrons and to induced magnetic field. We also extend this formulation by considering the presence of a precessing external magnetic field. These simulations are very realistic and present significant improvement with respect to previous phenomenological GRB simulations. They reproduce light curves of separate peaks of real GRBs and variety of spectral slopes at E > Epeak observed by the Fermi-LAT instrument. The high energy emission can be explained by synchrotron emission and a subdominant contribution from inverse Compton. We also suggest an explanation for extended tail emission and relate it to the screening of the magnetic field and/or trapping of accelerated electrons in the electromagnetic energy structure of the plasma in the shock front. Spectral slopes of simulated bursts at E external magnetic field, we show that due to the fast variation of other quantities, its signature in the Power Distribution Spectrum (PDS) is significantly suppressed and only when the duration of the burst is few times longer than the oscillation period it can be detected, otherwise either it is confused with the Poisson noise or with intrinsic variations of the emission. Therefore, low significant oscillations observed in the PDS of GRB 090709a are most probably due to a precessing magnetic field.

  1. A New Paradigm for Gamma Ray Bursts: Long Term Accretion Rate Modulation by an External Accretion Disk

    Science.gov (United States)

    Cannizzo, John; Gehrels, Neil

    2009-01-01

    We present a new way of looking at the very long term evolution of GRBs in which the disk of material surrounding the putative black hole powering the GRB jet modulates the mass flow, and hence the efficacy of the process that extracts rotational energy from the black hole and inner accretion disk. The pre-Swift paradigm of achromatic, shallow-to-steep "breaks" in the long term GRB light curves has not been borne out by detailed Swift data amassed in the past several years. We argue that, given the initial existence of a fall-back disk near the progenitor, an unavoidable consequence will be the formation of an "external disk" whose outer edge continually moves to larger radii due to angular momentum transport and lack of a confining torque. The mass reservoir at large radii moves outward with time and gives a natural power law decay to the GRB light curves. In this model, the different canonical power law decay segments in the GRB identified by Zhang et al. and Nousek et al. represent different physical states of the accretion disk. We identify a physical disk state with each power law segment.

  2. Gamma spectrometry on MANITU 271-01 gamma scan wires

    International Nuclear Information System (INIS)

    Dassel, G.; Buurveld, H.A.; Minkema, J.

    1994-08-01

    A series of irradiation experiments (271-series) is being performed of the sustain programme for material development and characterization of the NET (Next European Torus). In the framework of the first irradiation experiment 271-01, with irradiation up to 0.2 dpa, four gamma scan wires have been examined by gamma scanning. The purpose of the gamma scan wires (GSW) is to get information about the neutron fluence distribution in the capsules during irradiation. In the stainless steel wires the nuclides Co-58, Mu-54, Fe-59 and Co-60 are produced, are characteristic for fast and thermal neutron reactions. (orig./HP)

  3. 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)

  4. Research on securing no bacteria and nonfeverish property for disposable medical appliances. Inactivation of endotoxin by Co-60 γ ray

    International Nuclear Information System (INIS)

    Hosobuchi, Kazunari; Tanamoto, Kenichi; Haijima, Yuji.

    1996-01-01

    The contamination by fever-causing endotoxin has become a large problem in medical treatment field. In the industry manufacturing disposable medical appliances, the method of manufacturing endotoxin-free products is an important subject, and the development of the methods of inactivating and eliminating efficiently endotoxin is desired. As a part of this development, the possibility of inactivating endotoxin with Co-60 γ ray was examined. The sample was the endotoxin originated from E.Coli R3 F653 strain. For the irradiation, the Co-60 γ ray irradiation apparatus of 185 T-Bq in National Institute of Hygienic Sciences was used. The measurement of the activity of endotoxin was carried out by limulus test synthetic substrate method. The activity value of the endotoxin in aqueous solution decreased logarithmically with the increasing irradiation dose, and this decreasing tendency was not affected by the initial concentration of the endotoxin. The experiment of recovering freezing-dried endotoxin from a vial is described. The results of inactivating the endotoxin in dry system by γ ray are reported. (K.I.)

  5. Standard Practice for Minimizing Dosimetry Errors in Radiation Hardness Testing of Silicon Electronic Devices Using Co-60 Sources

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2010-01-01

    1.1 This practice covers recommended procedures for the use of dosimeters, such as thermoluminescent dosimeters (TLD's), to determine the absorbed dose in a region of interest within an electronic device irradiated using a Co-60 source. Co-60 sources are commonly used for the absorbed dose testing of silicon electronic devices. Note 1—This absorbed-dose testing is sometimes called “total dose testing” to distinguish it from “dose rate testing.” Note 2—The effects of ionizing radiation on some types of electronic devices may depend on both the absorbed dose and the absorbed dose rate; that is, the effects may be different if the device is irradiated to the same absorbed-dose level at different absorbed-dose rates. Absorbed-dose rate effects are not covered in this practice but should be considered in radiation hardness testing. 1.2 The principal potential error for the measurement of absorbed dose in electronic devices arises from non-equilibrium energy deposition effects in the vicinity o...

  6. Gamma ray induced fruit quality variations in banana variety Nendran (Musa Paradasiaca L.)

    International Nuclear Information System (INIS)

    Radha Devi, D.S.; Nayer, N.K.

    1992-01-01

    Gamma ray induced fruit quality variation was envisaged to analyse the direct effect of Co 60 gamma rays in banana variety Nendran. Fruit quality analysis showed that the total soluble solids and acidity decreased and total sugar and sugar acid ratio increased with increase in dose of gamma ray exposures. (author). 5 refs., 1 tab

  7. Estimation of Ni63, Pu241, Pu242 and Am243 from Co60, Pu239, and Cm244 activities in groundwater samples

    International Nuclear Information System (INIS)

    Holcomb, H.P.

    1993-01-01

    The Part B Permit for F ampersand H Seepage Basins calls for analysis of several constituents of concern in groundwater monitoring wells. Four of these analytes are the radionuclides Ni 63 , Pu 241 , Pu 242 , and Am 243 . These are currently not being analyzed due to their very difficult, tedious analytical schemes coupled with their relatively low activity values. This report demonstrates how the activity value for Ni 63 , a week beta emitter, can be estimated from that of Co 60 , an easily detectable, high-energy gamma emitter. Similarly, estimates of Pu 241 , a beta emitter, and the alpha-emitting Pu 242 can be made from the activity value of the more easily detected Pu 239 . Am 243 can be estimated from the activity of Cm 244 , which is easier to detect because of a shorter half-life (higher specific activity) and the emission of higher energy alpha particles. These correlations are made under very specific parameters in order to ensure the validity of this approach. Therefore, assumptions must be established setting ground rules for establishing these activity relationships. Bases for these assumptions are explained and/or referenced. Their degree of uncertainty limits the accuracy of the data so that the term ''estimate'' is used. Such soundly-based, conservative estimates for these four rads can provide a tool for evaluating any hazards from their presence over the next several years. Hopefully, during this time, sufficient advances will be made in their radiochemical analyses and in counting techniques so that in the future, their activities may be quantitatively determined more easily and also more cost effectively

  8. Correlation between Co-60 and X-ray exposures on radiation-induced charge buildup in silicon-on-insulator buried oxides

    International Nuclear Information System (INIS)

    Schwank, James R.; Shaneyfelt, Marty R.; Loemker, Rhonda Ann; Draper, Bruce L.; Dodd, Paul E.; Witczak, StevenN C.; Riewe, Leonard Charles; Ferlet-Cavrois, V.; Paillet, P.; Leray, J.-L.; Fleetwood, D.M.

    2000-01-01

    Large differences in charge buildup in SOI buried oxides can result between x-ray and Co-60 irradiations. The effects of bias configuration and substrate type on charge buildup and hardness assurance issues are explored

  9. TH-AB-BRA-02: Automated Triplet Beam Orientation Optimization for MRI-Guided Co-60 Radiotherapy

    International Nuclear Information System (INIS)

    Nguyen, D; Thomas, D; Cao, M; O’Connor, D; Lamb, J; Sheng, K

    2016-01-01

    Purpose: MRI guided Co-60 provides daily and intrafractional MRI soft tissue imaging for improved target tracking and adaptive radiotherapy. To remedy the low output limitation, the system uses three Co-60 sources at 120° apart, but using all three sources in planning is considerably unintuitive. We automate the beam orientation optimization using column generation, and then solve a novel fluence map optimization (FMO) problem while regularizing the number of MLC segments. Methods: Three patients—1 prostate (PRT), 1 lung (LNG), and 1 head-and-neck boost plan (H&NBoost)—were evaluated. The beamlet dose for 180 equally spaced coplanar beams under 0.35 T magnetic field was calculated using Monte Carlo. The 60 triplets were selected utilizing the column generation algorithm. The FMO problem was formulated using an L2-norm minimization with anisotropic total variation (TV) regularization term, which allows for control over the number of MLC segments. Our Fluence Regularized and Optimized Selection of Triplets (FROST) plans were compared against the clinical treatment plans (CLN) produced by an experienced dosimetrist. Results: The mean PTV D95, D98, and D99 differ by −0.02%, +0.12%, and +0.44% of the prescription dose between planning methods, showing same PTV dose coverage. The mean PTV homogeneity (D95/D5) was at 0.9360 (FROST) and 0.9356 (CLN). R50 decreased by 0.07 with FROST. On average, FROST reduced Dmax and Dmean of OARs by 6.56% and 5.86% of the prescription dose. The manual CLN planning required iterative trial and error runs which is very time consuming, while FROST required minimal human intervention. Conclusions: MRI guided Co-60 therapy needs the output of all sources yet suffers from unintuitive and laborious manual beam selection processes. Automated triplet orientation optimization is shown essential to overcome the difficulty and improves the dosimetry. A novel FMO with regularization provides additional controls over the number of MLC segments

  10. TH-AB-BRA-02: Automated Triplet Beam Orientation Optimization for MRI-Guided Co-60 Radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Nguyen, D; Thomas, D; Cao, M; O’Connor, D; Lamb, J; Sheng, K [Department of Radiation Oncology, University of California Los Angeles, Los Angeles, CA (United States)

    2016-06-15

    Purpose: MRI guided Co-60 provides daily and intrafractional MRI soft tissue imaging for improved target tracking and adaptive radiotherapy. To remedy the low output limitation, the system uses three Co-60 sources at 120° apart, but using all three sources in planning is considerably unintuitive. We automate the beam orientation optimization using column generation, and then solve a novel fluence map optimization (FMO) problem while regularizing the number of MLC segments. Methods: Three patients—1 prostate (PRT), 1 lung (LNG), and 1 head-and-neck boost plan (H&NBoost)—were evaluated. The beamlet dose for 180 equally spaced coplanar beams under 0.35 T magnetic field was calculated using Monte Carlo. The 60 triplets were selected utilizing the column generation algorithm. The FMO problem was formulated using an L2-norm minimization with anisotropic total variation (TV) regularization term, which allows for control over the number of MLC segments. Our Fluence Regularized and Optimized Selection of Triplets (FROST) plans were compared against the clinical treatment plans (CLN) produced by an experienced dosimetrist. Results: The mean PTV D95, D98, and D99 differ by −0.02%, +0.12%, and +0.44% of the prescription dose between planning methods, showing same PTV dose coverage. The mean PTV homogeneity (D95/D5) was at 0.9360 (FROST) and 0.9356 (CLN). R50 decreased by 0.07 with FROST. On average, FROST reduced Dmax and Dmean of OARs by 6.56% and 5.86% of the prescription dose. The manual CLN planning required iterative trial and error runs which is very time consuming, while FROST required minimal human intervention. Conclusions: MRI guided Co-60 therapy needs the output of all sources yet suffers from unintuitive and laborious manual beam selection processes. Automated triplet orientation optimization is shown essential to overcome the difficulty and improves the dosimetry. A novel FMO with regularization provides additional controls over the number of MLC segments

  11. In vitro evaluation of 213Bi-rituximab versus external gamma irradiation for the treatment of B-CLL patients: relative biological efficacy with respect to apoptosis induction and chromosomal damage

    International Nuclear Information System (INIS)

    Vandenbulcke, Katia; Lahorte, Christophe; Slegers, Guido; De Vos, Filip; Dierckx, Rudi A.; Offner, Fritz; Philippe, Jan; Apostolidis, Christos; Molinet, Roger; Nikula, Tuomo K.; Bacher, Klaus; De Gelder, Virginie; Vral, Anne; Thierens, Hubert

    2003-01-01

    External source radiotherapy and beta radioimmunotherapy (RIT) are effective treatments for lymphoid malignancies. The development of RIT with alpha emitters is attractive because of the high linear energy transfer (LET) and short path length, allowing higher tumour cell kill and lower toxicity to healthy tissues. We assessed the relative biological efficacy (RBE) of alpha RIT (in vitro) compared to external gamma irradiation with respect to induction of apoptosis in B chronic lymphocytic leukaemia (B-CLL) and induction of chromosomal damage in healthy donor B and T lymphocytes. The latter was measured by a micronucleus assay. 213 Bi was eluted from a 225 Ac generator and conjugated to CD20 antibody (rituximab) with CHX-A''-DTPA as a chelator. B-CLL cells from five patients were cultured for 24 h in RPMI/10% FCS while exposed to 213 Bi conjugated to CD20 antibody or after external 60 Co gamma irradiation. Binding assays were performed in samples of all patients to calculate the total absorbed dose. Apoptosis was scored by flow cytometric analyses of the cells stained with annexin V-FITC and 7-AAD. Apoptosis was expressed as % excess over spontaneous apoptosis in control. Full dose range experiments demonstrated 213 Bi-conjugated CD20 antibody to be more effective than equivalent doses of external gamma irradiation, but showed that similar plateau values were reached at 10 Gy. The RBE for induction of apoptosis in B-CLL was 2 between 1.5 and 7 Gy. The micronucleus yield in lymphocytes of healthy volunteers was measured to assess the late toxicity caused by induction of chromosomal instability. While gamma radiation induced a steady increase in micronucleus yields in B and T cells, the damage induced by 213 Bi was more dramatic, with RBE ranging from 5 to 2 between 0.1 Gy and 2 Gy respectively. In contrast to gamma irradiation, 213 Bi inhibited mitogen-stimulated mitosis almost completely at 2 Gy. In conclusion, high-LET targeted alpha particle exposure killed B

  12. In vitro evaluation of {sup 213}Bi-rituximab versus external gamma irradiation for the treatment of B-CLL patients: relative biological efficacy with respect to apoptosis induction and chromosomal damage

    Energy Technology Data Exchange (ETDEWEB)

    Vandenbulcke, Katia; Lahorte, Christophe; Slegers, Guido [Department of Radiopharmacy, Faculty of Pharmaceutical Sciences, Ghent University, Harelbekestraat 72, 9000, Gent (Belgium); De Vos, Filip; Dierckx, Rudi A. [Division of Nuclear Medicine, Ghent University Hospital (Belgium); Offner, Fritz [Department of Hematology, Ghent University Hospital (Belgium); Philippe, Jan [Department of Clinical Chemistry, Ghent University Hospital (Belgium); Apostolidis, Christos; Molinet, Roger; Nikula, Tuomo K. [European Commission, Joint Research Centre, Institute for Transuranium Elements, Karlsruhe (Germany); Bacher, Klaus; De Gelder, Virginie; Vral, Anne; Thierens, Hubert [Department of Anatomy, Embryology, Histology and Medical Physics, Ghent University (Belgium)

    2003-10-01

    External source radiotherapy and beta radioimmunotherapy (RIT) are effective treatments for lymphoid malignancies. The development of RIT with alpha emitters is attractive because of the high linear energy transfer (LET) and short path length, allowing higher tumour cell kill and lower toxicity to healthy tissues. We assessed the relative biological efficacy (RBE) of alpha RIT (in vitro) compared to external gamma irradiation with respect to induction of apoptosis in B chronic lymphocytic leukaemia (B-CLL) and induction of chromosomal damage in healthy donor B and T lymphocytes. The latter was measured by a micronucleus assay. {sup 213}Bi was eluted from a {sup 225}Ac generator and conjugated to CD20 antibody (rituximab) with CHX-A''-DTPA as a chelator. B-CLL cells from five patients were cultured for 24 h in RPMI/10% FCS while exposed to {sup 213}Bi conjugated to CD20 antibody or after external {sup 60}Co gamma irradiation. Binding assays were performed in samples of all patients to calculate the total absorbed dose. Apoptosis was scored by flow cytometric analyses of the cells stained with annexin V-FITC and 7-AAD. Apoptosis was expressed as % excess over spontaneous apoptosis in control. Full dose range experiments demonstrated {sup 213}Bi-conjugated CD20 antibody to be more effective than equivalent doses of external gamma irradiation, but showed that similar plateau values were reached at 10 Gy. The RBE for induction of apoptosis in B-CLL was 2 between 1.5 and 7 Gy. The micronucleus yield in lymphocytes of healthy volunteers was measured to assess the late toxicity caused by induction of chromosomal instability. While gamma radiation induced a steady increase in micronucleus yields in B and T cells, the damage induced by {sup 213}Bi was more dramatic, with RBE ranging from 5 to 2 between 0.1 Gy and 2 Gy respectively. In contrast to gamma irradiation, {sup 213}Bi inhibited mitogen-stimulated mitosis almost completely at 2 Gy. In conclusion, high

  13. Liver dysfunction following whole-body Co-60 irradiation in gerbil (Meriones hurrianae Jerdon) and house rat (Rattus rattus rufescens)

    International Nuclear Information System (INIS)

    Dixit, V.P.; Agrawal, M.; Gupta, C.

    1976-01-01

    Liver dysfunction following whole-body Co-60 irradiation has been studied in domestic and desert rat species. A significant elevation in the serum transaminases activity was noticed both in gerbil and house rat. Alkaline phosphatase and plasma cholesterol levels were also increased indicating an early radiation impairment of the liver tissue, which was later confirmed by histological studies. A steady fall in liver glycogen in irradiated gerbils was strikingly in contrast to an increase in irradiated house rat. Drastic depletion in liver glycogen, changes in the serum enzyme levels and the severity of the hepatic necrosis in gerbils point out that desert mammalian species are much more sensitive to radiation hazard as compared with domestic ones. (orig.) [de

  14. Monte Carlo dosimetric characterization of the Flexisource Co-60 high-dose-rate brachytherapy source using PENELOPE.

    Science.gov (United States)

    Almansa, Julio F; Guerrero, Rafael; Torres, Javier; Lallena, Antonio M

    60 Co sources have been commercialized as an alternative to 192 Ir sources for high-dose-rate (HDR) brachytherapy. One of them is the Flexisource Co-60 HDR source manufactured by Elekta. The only available dosimetric characterization of this source is that of Vijande et al. [J Contemp Brachytherapy 2012; 4:34-44], whose results were not included in the AAPM/ESTRO consensus document. In that work, the dosimetric quantities were calculated as averages of the results obtained with the Geant4 and PENELOPE Monte Carlo (MC) codes, though for other sources, significant differences have been quoted between the values obtained with these two codes. The aim of this work is to perform the dosimetric characterization of the Flexisource Co-60 HDR source using PENELOPE. The MC simulation code PENELOPE (v. 2014) has been used. Following the recommendations of the AAPM/ESTRO report, the radial dose function, the anisotropy function, the air-kerma strength, the dose rate constant, and the absorbed dose rate in water have been calculated. The results we have obtained exceed those of Vijande et al. In particular, the absorbed dose rate constant is ∼0.85% larger. A similar difference is also found in the other dosimetric quantities. The effect of the electrons emitted in the decay of 60 Co, usually neglected in this kind of simulations, is significant up to the distances of 0.25 cm from the source. The systematic and significant differences we have found between PENELOPE results and the average values found by Vijande et al. point out that the dosimetric characterizations carried out with the various MC codes should be provided independently. Copyright © 2017 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.

  15. A comprehensive study on HDR brachytherapy treatments of cervical cancers: using the first Co-60 BEBIG Multisource Unit in Bangladesh

    Directory of Open Access Journals (Sweden)

    Naheed Rukhsana

    2011-07-01

    Full Text Available Purpose: The report presents an extraordinary synthesis of customer acceptance procedures (CAP, quality assurance tests (QA in the treatment of cervical cancer patients, using the first Co-60 Multisource Unit® in Bangladesh. The QA and commissioning required measurements and emergency tests verifying the functional limits of parameters acceptable for the new HDR afterloader. Acceptable limits were: 1 the deviation between specified and measured source strength: ± 3%; 2 the positional accuracy and uniformity: ± 1 mm; 3 the temporal accuracy (i.e. timer error and linearity and end error: ± 1% or 30 sec.; 4 treatment planning system (digitizer and localization software: ± 3% or 1 mm; 5 the distance from line to first dwell position and all the others: 5 mm and 10 mm (± 1 mm. Material and methods: Till February 2011, 47 patients were treated with HDR with more than 140 insertions applied. Amongst them, 12 patients were in stage IIB and IIIB, 22 were postoperative (IA and IB while the remaining 13 patients were with unknown stage. All the cases with stage IIB and IIIB received concurrent chemo-radiation and brachytherapy. Postoperative patients received EBRT (50 Gy and HDR according to the institutional protocol. CT scans were completed before HDR-plus planning with a good reproducibility (± 2% and were documented in repeating the plan for the same set up of a patient. Absorbed dose (Gy to a point P, at a distance of “r” in centimeters from a source of the Reference Air Kerma Rate (RAKR has been utilized for the QA of the source, where source strength measurement was accomplished. Results: All methods and analysis applicable to the QA and commissioning of Co-60 have been investigated and systematically analyzed, measured and documented before the treatment of a patient. Studies and safety requirements of this HDR remote afterloader were carried out. Acceptance and the QA were imperative to justify functionality and dependability in

  16. A comprehensive study on HDR brachytherapy treatments of cervical cancers: using the first Co-60 BEBIG Multisource Unit in Bangladesh.

    Science.gov (United States)

    Malik, Sadiq R; Banu, Parvin A; Rukhsana, Naheed

    2011-06-01

    The report presents an extraordinary synthesis of customer acceptance procedures (CAP), quality assurance tests (QA) in the treatment of cervical cancer patients, using the first Co-60 Multisource Unit ® in Bangladesh. The QA and commissioning required measurements and emergency tests verifying the functional limits of parameters acceptable for the new HDR afterloader. Acceptable limits were: 1) the deviation between specified and measured source strength: ± 3%; 2) the positional accuracy and uniformity: ± 1 mm; 3) the temporal accuracy (i.e. timer error and linearity and end error): ± 1% or 30 sec.; 4) treatment planning system (digitizer and localization software): ± 3% or 1 mm; 5) the distance from line to first dwell position and all the others: 5 mm and 10 mm (± 1 mm). Till February 2011, 47 patients were treated with HDR with more than 140 insertions applied. Amongst them, 12 patients were in stage IIB and IIIB, 22 were postoperative (IA and IB) while the remaining 13 patients were with unknown stage. All the cases with stage IIB and IIIB received concurrent chemo-radiation and brachytherapy. Postoperative patients received EBRT (50 Gy and HDR) according to the institutional protocol. CT scans were completed before HDR-plus planning with a good reproducibility (± 2%) and were documented in repeating the plan for the same set up of a patient. Absorbed dose (Gy) to a point P, at a distance of "r" in centimeters from a source of the Reference Air Kerma Rate (RAKR) has been utilized for the QA of the source, where source strength measurement was accomplished. All methods and analysis applicable to the QA and commissioning of Co-60 have been investigated and systematically analyzed, measured and documented before the treatment of a patient. Studies and safety requirements of this HDR remote afterloader were carried out. Acceptance and the QA were imperative to justify functionality and dependability in delivering the treatment. Implications of these studies

  17. Results of calculations of external gamma radiation exposure rates from fallout and the related radionuclide compositions. Operation Tumbler-Snapper, 1952

    International Nuclear Information System (INIS)

    Hicks, H.G.

    1981-07-01

    This report presents data on calculated gamma radiation exposure rates and ground deposition of related radionuclides resulting from Events that deposited detectable radioactivity outside the Nevada Test Site complex

  18. An experimental study of the effect of Co-60 irradiation on the healing process of extraction wounds in white rats

    Energy Technology Data Exchange (ETDEWEB)

    You, Young Jun; Ahn, Hyung Kyu [Dept. of Dental Radiology, Graduate School, Seoul National University, Seoul (Korea, Republic of)

    1982-11-15

    Because of the development of rampant caries, osteomyelitis and osteoradionecrosis that occur after radiation therapy of oral cancers, extraction of teeth at or near the malignant lesion has been done in the past. Few, however, have studied the radiation effect on the healing of extraction wounds. The study is concerned with the effect of Co-60 irradiation on the healing process of extraction wounds in rats. Fifty six, male, Sprague-Dawley rats are used. The right first molar of the mandible is extracted from all animals. They are divided into three experimental groups of 14 each and a control group of 14. There experimental groups are irradiated respectively with 200 rad, 400 rad and 600 rad and a pair of rats in each group are killed on days 1, 3, 5, 7, 14, 21 and 28 after irradiation. Two animals from the control group are killed on the day when the experimental rats are killed. The irradiated hemimandibles are fixed in 10% neutral formalin, decalcified in 5% trichloroacetic acid, embedded in paraffin and sectioned. The sections are stained in hematoxylin and eosin, van Gison, Masson's trichrome or silver nitrate. Results show that in general radiation effects on healing extraction wounds are dose dependent; i.e., the higher is the dose, the greater is the histologic changes observed: 1. Irradiation tends to retard blood clot organization and epithelial regeneration. 2. An increase in the number of giant cells and osteoclasts is noted after irradiation. 3. Formation of regenerating connective tissues around and within the extraction site is compromised, and a clear reduction of primitive mesenchymal type connective cells is noted. 4. The healing process begins along the lateral aspect of the extraction socket in the control, while irregular histologic appearances of the trabecular pattern is present in the experimental rats.

  19. Evaluation of small scale laboratory and pot experiments to determine realistic transfer factors for the radionuclides Sr-90, Cs-137, Co-60 and Mn-54

    International Nuclear Information System (INIS)

    Steffens, W.; Fuhr, F.; Mittelstaedt, W.

    1980-01-01

    Lysimeter experiments were undertaken in a controlled experimental field to study the root uptake of Sr-90, Cs-137, Co-60 and Mn-54 under outdoor conditions. Parallel experiments were set up using the Kick - Brauckman experimental pots under greenhouse and the Neubauer cups under growth chamber conditions. The results obtained from the three types of experiments are compared. (H.K.)

  20. Example of dealing with the accident during therapeutical application of Co-60 at one institute of oncology and radiology in Serbia

    International Nuclear Information System (INIS)

    Ilic, Z.; Perisic, J.; Vukcevic, M.; Joksic, G.; Spasojevic-Tisma, V.; Cuknic, O.; Milanovic, S.; Djuric, J.; Konstantinovic, J.; Ilic, Z.)

    2007-01-01

    This article describes an example of dealing with the accident during therapeutical application of Co-60 to a gynaecological patient. The accident happened when the sonde with Ca-60 drop out from the original postament, and was held by nurse and with bare hands storaged into his own special container [sr

  1. TLD Postal service for quality audits of beams of Co-60 in reference conditions in Cuba; Servicio Postal TLD para auditorias de calidad de haces de Co-60 en condiciones de referencia en Cuba

    Energy Technology Data Exchange (ETDEWEB)

    Gutierrez L, S.; Walwyn S, G.; Alonso V, G. [CPHR, Calle 20 No. 4113 e/41 y 47, Playa, C.P. 11300, C. Habana (Cuba)]. e-mail: stefan@cphr.edu.cu

    2006-07-01

    Purpose: To describe the methodology and experience of the Secondary Laboratory of Dosimetric Calibration of Cuba in the establishment of the TLD Postal Service for quality audits of beams of Co-60 in reference conditions. Materials and methods: Through the Coordinated Project of Research (Contract 10794) its was bought 200 solid thermoluminescent detectors of LiF: Mg, Ti (TLD-100) in micro bars form with dimensions of 6 x 1 x 1 mm and of the JR 1152F type manufactured in China. All these detectors were identified individually with a serial number on one of its faces, using a graphite fine sheet. Those detectors for its irradiation are introduced in cylindrical plastic capsules developed and used by the International Atomic Energy Agency (IAEA) in the Audit Postal Service of Dose IAEA/WHO, the capsules have one cavity equal to 3 mm for that is necessary to recover this cavity with a fine plastic tube so that the detectors remain immobile during the irradiation. The method used to determine the individual sensitivity of the thermoluminescent detectors is: to irradiate a detectors group (100 micro bars) 4 times in those same geometric conditions, with the same irradiation history and reading, then it is determine for each detector a sensitivity factor equal to the average of those readings obtained for the 4 irradiation cycles for each i detector among the average of all the reading values obtained during the 4 cycles. The thermoluminescent signal is obtained with a Harshaw 2000C/B reader manual. Results: The satisfactory results obtained in the verification of the calibration of the TLD system, using the reference irradiation service of the Seibersdorf Dosimetry Laboratory of the IAEA in three different years are shown. The results of the audits carried out to the different radiotherapy services of the country in different years are also presented. Conclusions: The experience with the detectors acquired in the project demonstrates that with an appropriate

  2. SU-F-T-28: Evaluation of BEBIG HDR Co-60 After-Loading System for Skin Cancer Treatment Using Conical Surface Applicator

    Energy Technology Data Exchange (ETDEWEB)

    Safigholi, H; Soliman, A; Song, W Y [Department of Medical Physics, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, ON (Canada); Meigooni, A S [Department of Radiation Therapy, Comprehensive Cancer Center of Nevada, Las Vegas, NV (United States); Han, D [Departemt of Radiation Oncology, University of California San Francisco, San Francisco, CA (United States)

    2016-06-15

    Purpose: To evaluate the possibility of utilizing the BEBIG HDR 60Co remote after-loading system for malignant skin surface treatment using Monte Carlo (MC) simulation technique. Methods: First TG-43 parameters of BEBIG-Co-60 and Nucletron Ir-192-mHDR-V2 brachytherapy sources were simulated using MCNP6 code to benchmark the sources against the literature. Second a conical tungsten-alloy with 3-cm diameter of Planning-Target-Volume (PTV) at surface for use with a single stepping HDR source is designed. The HDR source is modeled parallel to treatment plane at the center of the conical applicator with a source surface distance (SSD) of 1.5-cm and a removable plastic end-cap with a 1-mm thickness. Third, MC calculated dose distributions from HDR Co-60 for conical surface applicator were compared with the simulated data using HDR Ir-192 source. The initial calculations were made with the same conical surface applicator (standard-applicator) dimensions as the ones used with the Ir-192 system. Fourth, the applicator wall-thickness for the Co-60 system was increased (doubled) to diminish leakage dose to levels received when using the Ir-192 system. With this geometry, percentage depth dose (PDD), and relative 2D-dose profiles in transverse/coronal planes were normalized at 3-mm prescription-depth evaluated along the central axis. Results: PDD for Ir-192 and Co-60 were similar with standard and thick-walled applicator. 2D-relative dose distribution of Co-60, inside the standard-conical-applicator, generated higher penumbra (7.6%). For thick-walled applicator, it created smaller penumbra (<4%) compared to Ir-192 source in the standard-conicalapplicator. Dose leakage outside of thick-walled applicator with Co-60 source was approximately equal (≤3%) with standard applicator using Ir-192 source. Conclusion: Skin cancer treatment with equal quality can be performed with Co-60 source and thick-walled conical applicators instead of Ir-192 with standard applicators. These conical

  3. Airborne and total gamma absorbed dose rates at Patiala - India

    International Nuclear Information System (INIS)

    Tesfaye, Tilahun; Sahota, H.S.; Singh, K.

    1999-01-01

    The external gamma absorbed dose rate due to gamma rays originating from gamma emitting aerosols in air, is compared with the total external gamma absorbed dose rate at the Physics Department of Punjabi University, Patiala. It has been found out that the contribution, to the total external gamma absorbed dose rate, of radionuclides on particulate matter suspended in air is about 20% of the overall gamma absorbed dose rate. (author)

  4. Results of calculations of external gamma radiation exposure rates from local fallout and the related radionuclide compositions of two hypothetical 1-MT nuclear bursts. Final report

    International Nuclear Information System (INIS)

    Hicks, H.

    1984-12-01

    This report presents data on calculated gamma radiation exposure rates and local surface deposition of related radionuclides resulting from two hypothetical 1-Mt nuclear bursts. Calculations are made of the debris from two types of bombs: one containing 235 U as a fissionable material (designated oralloy), the other containing 238 U (designated tuballoy). 4 references

  5. Procedures for calibration of clinical dosemeters of radiotherapy with gamma radiation Co-60 in the IPEN-CNEN, Sao Paulo, Brazil

    International Nuclear Information System (INIS)

    Damatto, Willian B.; Santos, Gelson P.; Potiens, Maria da Penha A.; Vivolo, Vitor

    2009-01-01

    The periodic calibration of clinic dosimeters is a very important task, because those measurement systems performing the control quality of the radioactive source and for that assure the control quality of the patient dose estimative. This paper shows the calibration procedures and routine improved in the calibration laboratory of IPEN/CNEN-SP to be applied to the clinic dosimeters following international and national recommendations and yet the spend care that the clients should have with the utilization of that measurement systems for control quality of the radiotherapy procedures, for reduce the dose received for patient, and workers, and for increase the confidence level of the measurements.(author)

  6. On some peculiarities of oil-resisting rubbers production from nitrile rubber of different composition by the use of Co60 gamma irradiation

    International Nuclear Information System (INIS)

    Mamedov, Sh.M.; Nelikzade, M.M.; Mamedov, A.A.

    1976-01-01

    The physicomechanical properties and swelling of vulcanizates were studied by means of radiation vulcanization. The test samples were preheated and formed by a press at 154 deg C for 3 min. Irradiation was performed in atmosphere on 60 Co (dosage 0.48 Mrad/hr). Irradiation caused decrease in tensile strength, as well as relative and permanent elongation; at the same time it considerably strengthened rubber hardness. All the rubber samples showed greater strength after irradiation under 5.7-13.8 Mrad. Depending on the dosage (3.6-13.8 Mrad), the relative and permanent elongation of vulcanizates obtained with the aid of altax was found to decrease, while strength and swelling increased. The swelling of rubber samples obtained with thiurad and thiuradaltax compounds decreased. Hence the advisability of using that rubber for manufacture of petroleum-resistant products

  7. Synthesis of Gold Nanoparticles Stabilized in Dextran Solution by Gamma Co-60 Ray Irradiation and Preparation of Gold Nanoparticles/Dextran Powder

    Directory of Open Access Journals (Sweden)

    Phan Ha Nu Diem

    2017-01-01

    Full Text Available Gold nanoparticles (AuNPs in spherical shape with diameter of 6–35 nm stabilized by dextran were synthesized by γ-irradiation method. The AuNPs were characterized by UV-Vis spectroscopy and transmission electron microscopy. The influence of pH, Au3+ concentration, and dextran concentration on the size of AuNPs was investigated. Results indicated that the smallest AuNPs size (6 nm and the largest AuNPs size (35 nm were obtained for pH of 1 mM Au3+/1% dextran solution of 5.5 and 7.5, respectively. The smaller Au3+ concentration favored smaller size and conversely the smaller dextran concentration favored bigger size of AuNPs. AuNPs powders were prepared by spay drying, coagulation, and centrifugation and their sizes were also evaluated. The purity of prepared AuNPs powders was also examined by energy dispersive X-ray (EDX analysis. Thus, the as-prepared AuNPs stabilized by biocompatible dextran in solution and/or in powder form can be potentially applied in biomedicine and pharmaceutics.

  8. Radiorestoration properties of several cytokinin-like substances on the normal tissues of Jerusalem artichoke treated by Co60 gamma-rays

    International Nuclear Information System (INIS)

    Jonard, Robert; Bayonove, Jacqueline

    1976-01-01

    6 cytokinin-like substances, particularly zeatin and isopentenyladenin (IPA) contained in yeast extract and their RNA prove to be effective radiorestorative agents on Jerusalem artichoke tissues cultivated in vitro; and their restorative activity is greater than that of kinetin [fr

  9. Gamma- irradiation to increase crop production

    International Nuclear Information System (INIS)

    Nomai, Matongo

    2000-01-01

    Brief background information on past research activities on the use of Co-60 Gamma Irraditor in production of medical products such as sterilised biological tissue grafts and surgical Gloves and in food preservation.The general results of the application of Radiation Mutation Breeding is discussed from the current research activities involving Beans,Pumpkins,Cotton Seeds,Finger Millet,Wheat,Groundnuts and Rice.The focus is to demonstrate the great potential of the technique in increasing food security

  10. Evaluation of gamma-ray intensities

    International Nuclear Information System (INIS)

    Yoshizawa, Yasukazu; Inoue, Hikaru; Hoshi, Masaharu; Shizuma, Kiyoshi; Iwata, Yosei.

    1978-03-01

    Results of literature survey and evaluation of relative intensities and intensities per decay of gamma rays are presented. Evaluations were made for 22 Na, 24 Na, 46 Sc, 48 Sc, 48 V, 54 Mn, 57 Co, 60 Co, 85 Sr, 88 Y, 95 Nb, 95 Zr, sup(108m)Ag, 134 Cs, 137 Cs, 144 Ce, 144 Pr, 203 Hg, and 207 Bi. For eight of the nuclides, the half-lives were also evaluated. (auth.)

  11. Regional Externalities

    NARCIS (Netherlands)

    Heijman, W.J.M.

    2007-01-01

    The book offers practical and theoretical insights in regional externalities. Regional externalities are a specific subset of externalities that can be defined as externalities where space plays a dominant role. This class of externalities can be divided into three categories: (1) externalities

  12. Co-60線源の分離による照射効率と線量均一度の向上

    OpenAIRE

    星 龍夫

    1986-01-01

    線源を2分割し、適当な間隔をおいて配置すると効率的で均一な照射を行なえることを実証した。またCo-60線状線源を中心におく円筒型照射装置及びCo-60平板線源によって照射するコンベア照射装置の照射性能を高めるため線源間隔の最適地を求めた。

  13. X-ray and gamma radiography devices

    International Nuclear Information System (INIS)

    Abdul Nassir Ibrahim; Azali Muhammad; Ab. Razak Hamzah; Abd. Aziz Mohamed; Mohamad Pauzi Ismail

    2008-01-01

    When we are using this technique, we also must familiar with the device and instrument that used such as gamma projector, crawler, x-ray tubes and others. So this chapter discussed detailed on device used for radiography work. For the x-ray and gamma, their characteristics are same but the source to produce is a big different. X-ray produced from the machine meanwhile, gamma produce from the source such as Co-60 and IR-192. Both are electromagnetic waves. So, the reader can have some knowledge on what is x-ray tube, discrete x-ray and characteristic x-ray, how the machine works and how to control a machine, what is source for gamma emitter, how to handle the projector and lastly difference between x-ray and gamma. Of course this cannot be with the theory only, so detailed must be learned practically.

  14. Verification of the dose in the inspection modules of Co-60 from Mexicali, B.C.N. through thermoluminescent dosimetry; Verificacion de la dosis en los modulos de inspeccion de Co-60 de Mexicali, B.C. mediante dosimetria termoluminiscente

    Energy Technology Data Exchange (ETDEWEB)

    Cruz C, D.; Azorin, J.; Rivera, T. [UAM-I, 09340 Mexico D.F. (Mexico)

    2005-07-01

    On the February and April 2005 months, there entered in operation two inspection modules, in the mexican border city of Mexicali. B.C.N., those which they work based on gamma rays, emitted by sources of {sup 60} Co; this fact generate a concern, on the part of the population of this city. Soon after these events, a group of personages of the local politics, they began a campaign, in favor of closing these modules, based on the supposition, of that the emitted radiation by these sources, represents a danger for health of people that uses the international crossing located to a side of the porter lodge 1, as well as of the population in general. As service to the community border of Mexico specifically to the population of Mexicali, B.C.N. city, inhabitants of this city, municipal, state and federal authorities and, the outstanding preoccupation of the Republic Senate (Commission of Border Affairs), the National Commission of Nuclear Security and Safeguards (CNSNS) they requested the support of the Metropolitan Autonomous University (UAM) and of the National Polytechnic Institute (IPN) to verify the radiation levels in the facilities of the sources of {sup 60} Co of the porter lodges of Mexicali-Calexico proceeding to the monitoring of this facilities in the period of 14-17 June 2005, 17 using thermoluminescent dosemeters elaborated in Mexico. (Au0010th.

  15. Assessment of the radiomodifying effect of the herbal preparation 'Elixir-3' in laboratory animals exposed to external whole-body gamma irradiation

    International Nuclear Information System (INIS)

    Tenchova, V.; Topalova, S.; Stefanova, D.; Kuzova, K.

    2002-01-01

    The study of preparations obtained from natural products, free of any toxic effects on the organism, has important practical implications on the prophylaxis against and correction of eventual sequelae of ionizing radiation. It is the purpose of the study to assay the radiomodifying action of the herbal preparation 'Elixir-3' (E-3) on mice exposed to acute whole-body irradiation with 3 and 7 Gy gamma-rays, using a prophylactic-therapeutic scheme of application over 30 days. E-3 represents alcohol-water extract of basil, hops, briar, nettle, walnut and peppermint. Bone marrow femoral and spleen cellularity, endogenous spleen colony-forming units (E-CFUs), overall plasma oxidation activity and phagocytic activity of neutrophils are evaluated. E-3, administered in a prophylactic-therapeutic scheme, promotes post-radiation recovery of hematopoiesis in mice irradiated with non-lethal and median-lethal gamma ray doses, and exerts a favourable effect on the anti-oxidation status and phagocytic activity of neutrophils in laboratory animals.(authors)

  16. Immediate and long-term effects in the hematopoietic system and the morphology of the respiratory system in experimental animals under chronic combined action of external gamma exposure and inhalation exposure.

    Science.gov (United States)

    Tatarkin, Sergey; Moukhamedieva, Lana; Aleksandr, Shafirkin; Barantseva, Maria; Ivanova, Svetlana

    The need to solve hygiene problems valuation of environmental factors in the implementation of the projected manned interplanetary missions, determined the relevance of studying the effect of external gamma-irradiation with inhalation of mixtures of chemicals on the parameters of major critical body systems: hematopoiesis and respiratory (morphological and morphometric parameters) in the short and long periods. The study conducted on 504 male mice F1 (CBA × C57BL6) under chronic fractional gamma-irradiation (within 10 weeks at a total dose 350sGr) and then under inhalation by mixtures of chemicals in low concentrations. Duration of the experiment (124 days) and 90 -day recovery period. Displaying adaptive reorganization in hematopoietic system, which was characterized by a tension of regulatory systems of animals and by a proliferation of bone marrow cells and by dynamic changes in amount of lymphoid cells in peripheral blood, elevated levels of the antioxidant activity of red blood cells, and morphological manifestations of "incomplete recovery " of the spleen, which are retained in the recovery period. Morphological changes in the respiratory organs of animals testified about immunogenesis activation and development of structural changes as a chronic inflammatory process. Increase of fibrous connective tissue in the walls of the trachea, bronchus and lung, against reduction of loose fibrous connective tissue (more pronounced in respiratory parts of the respiratory system) in experimental animals, which may indicate a reduction of the functional reserves of the body and increase the risk of adverse long-term effects.

  17. Verification of the dose in the inspection modules of Co-60 from Mexicali, B.C.N. through thermoluminescent dosimetry

    International Nuclear Information System (INIS)

    Cruz C, D.; Azorin, J.; Rivera, T.

    2005-01-01

    On the February and April 2005 months, there entered in operation two inspection modules, in the mexican border city of Mexicali. B.C.N., those which they work based on gamma rays, emitted by sources of 60 Co; this fact generate a concern, on the part of the population of this city. Soon after these events, a group of personages of the local politics, they began a campaign, in favor of closing these modules, based on the supposition, of that the emitted radiation by these sources, represents a danger for health of people that uses the international crossing located to a side of the porter lodge 1, as well as of the population in general. As service to the community border of Mexico specifically to the population of Mexicali, B.C.N. city, inhabitants of this city, municipal, state and federal authorities and, the outstanding preoccupation of the Republic Senate (Commission of Border Affairs), the National Commission of Nuclear Security and Safeguards (CNSNS) they requested the support of the Metropolitan Autonomous University (UAM) and of the National Polytechnic Institute (IPN) to verify the radiation levels in the facilities of the sources of 60 Co of the porter lodges of Mexicali-Calexico proceeding to the monitoring of this facilities in the period of 14-17 June 2005, 17 using thermoluminescent dosemeters elaborated in Mexico. (Author)

  18. Radiation breeding researches in gamma field. Results of researches

    International Nuclear Information System (INIS)

    Morishita, Toshikazu

    2006-01-01

    Abstract of radiation breeding researches and outline of gamma field in IRB (Institute of Radiation Breeding) are described. The gamma field is a circular field of 100 m radius with 88.8TBqCo-60 source at the center. The field is surrounded by a shielding dike of 8 m in height. The effects of gamma irradiation on the growing plants, mutant by gamma radiation and plant molecular biological researches using mutant varieties obtained by the gamma field are explained. For examples, Japanese pear, chrysanthemum, Cytisus, Eustoma grandiflorum, Manila grass, tea and rose are reported. The mutant varieties in the gamma field, nine mutant varieties of flower colors in chrysanthemum, evergreen mutant lines in Manila grass, selection of self-compatible mutants in tea plant, and the plants of the gamma field recently are shown. (S.Y.)

  19. Development of a purification technology for treatment of medium- and low-activity radioactive waste of radiochemical production from Co-60 and Cs-137

    Directory of Open Access Journals (Sweden)

    Apalkov Gleb

    2016-01-01

    Full Text Available The technological flowchart of purification of medium- and low-activity waste from Co-60 and Cs-137 is developed and introduced. The developed purification scheme has been successfully tested using genuine medium- and low-level liquid radioactive waste of radiochemical production containing complexing and colloid forming components complexons, surfactants. The optimal conditions of the presented method of purification ensure reduction of the residual specific activity of 60Co and 137Cs radionuclides in the solution to less than 0,9 Bq per litre.

  20. Quantitative modifications of T-lymphocyte subpopulations in inoperable patients irradiated with Co60 in the area of neck and interpleural space

    International Nuclear Information System (INIS)

    Beyer-Enke, S.A.; Strauss, L.G.; Gajzer, S.; Georgi, M.

    1987-01-01

    Several parameters of red and white blood components were determined in twelve patients submitted to Co 60 -irradiations for inoperable tumors in the area of neck and interpleural space. Some statistically significant, dose-dependent modifications were found for leucocytes, thrombocytes and lymphocytes. A considerable radiogenic reduction was demonstrated especially for helper cells, suppressor cells and natural killer cells. A different radiosensitivity could not be proved for these lymphocyte subpopulations. A possible influence of disease-specific endogenous as well as exogenous factors was discussed. (orig.) [de

  1. Background radiation accumulation and lower limit of detection in thermoluminescent beta-gamma dosimeters used by the centralized external dosimetry system

    International Nuclear Information System (INIS)

    Sonder, E.; Ahmed, A.B.

    1991-12-01

    A value for ''average background radiation'' of 0.75 mR/week has been determined from a total of 1680 thermoluminescent dosimeters (TLD's) exposed in 70 houses for periods up to one year. The distribution of results indicates a rather large variation among houses, with a few locations exhibiting backgrounds double the general average. Some discrepancies in the short-term background accumulation of TLD's have been explained as being due to light leakage through the dosimeter cases. In addition the lower limit of detection (L D ) for deep and shallow dose equivalents has been determined for these dosimeters. The L D for occupational exposure depends strongly on the time a dosimeter is exposed to background radiation in the field. The L D can vary from a low of 2.4 mrem for high energy gamma rays when the background accumulation period is less than a few weeks to values as high as 66 mrem for uranium beta particles when background has been allowed to accumulate for more than 21 weeks

  2. Methodological issues in protein and lipidic expressions in brain tissue exposed to Co60 based on DESI/MALDI-MS

    International Nuclear Information System (INIS)

    Soares, Matheus F.; Campos, Tarcísio P.R.; Augusti, Rodinei; Eberlin, Marcos N.; Vendramini, Pedro H.

    2017-01-01

    The present paper attempts to present some issues in the methodology of identifying lipid and protein changes in brain tissue induced by radiation. The goal was to address the analysis of the methodology and to investigate the feasibility of the generation of lipid/protein profiles of irradiated brain tissue, in order to identify radioinduced changes. Lipids and proteins are biomolecules with diverse structures and functionalities that participate in important intracellular processes. Changes in the lipid and the tissue protein profiles may indicate a cellular response to an external stimulus as well as the emergence of neoplasms or neurodegenerative diseases such as Alzheimer's. DESI-MS is a convenient method for identifying lipids and their spatial distribution in tissue beyond analytical quantification. DESI-MS allows the creation of an image of several low lipid m/z classes. MALDI-MS has already been a method used in the study of macromolecules as structural, membrane, hormone, neuromediator and immunological peptides. Through a full-scan matrix scan, with a m/z spectrum between 500-1000 for lipids and with a mass spectrum of 1000-15000 Da for proteins, the molecular profile can be analyzed. Generated pixel shape 2D chemical image. The produced image allows to associate the tissue distribution of the lipids and proteins with their chemical profile identified, allowing the verification of the changes radioinduced. Radiation triggers intense oxidative stress by increasing reactive oxygen species (ROS) and free radicals, causing DNA damage with consequent alterations in proteomics and cellular lipid explaining such changes in the lipid and protein expressions. The cellular morphophysiological changes are responsible for both the clonogenic inhibition and the induction of the apoptotic process. The images's production was directly dependent on the rigorous execution of the methodological procedures. Innumerable interferences could impair the image

  3. Gamma radiation field extremity personal dosimeter. Calibration and implementation

    International Nuclear Information System (INIS)

    Papadopulos, S.B.; Gregori, B.N.; Cruzate, J.A.

    2000-01-01

    The purpose of this paper is to show the extremity dose equivalent-kerma conversion factors obtained theoretical and experimentally in arm and finger for normally incident gamma radiation. Extremity dosemeters, based on termoluminescent dosimeters (TLD) LiF 7 (TLD-700, Harshaw), have been irradiated on designed as finger and arm phantoms. The finger phantom is been characterised as a solid cylinder made of polymethylmethacrylate (PMMA) 19mm diameter and 300mm height. The arm phantom is a cylinder 73mm external diameter with PMMA walls 2.5mm thick filled with water and 300mm height. There were used several radiation sources like Co-60 and Cs-137 from the Regional Reference Dosimetry Centre (CRR) of the National Atomic Energy Commission (CNEA) and from the Nuclear Regulatory Authority (ARN) of Argentina. In the same way RX wide spectrum irradiations were made in the ISO-4037 qualities W60, W110 and W200. At the same time the conversion factors have been theoretically obtained. In order to achieve this, the finger and arm phantoms have been modelled and the photon and electron transport have been done with the Monte Carlo code MCNP-4B. There was a good agreement between the theoretical and experimental results, showing a difference less than 8%. Also the experimental results have been compared with the published data available giving a difference less than 7%. In this work is shown the performance of the extremity dosimeter usually used by the exposed workers of the ARN. It has got a similar energy response in the range of W110-Co-60 (not more than 7%) with respect to the experimental results obtained. The dose equivalent-kerma conversion factors are going to be used in the dose equivalent evaluation of workers mainly hands exposed. Related with the incident energy several applied recommendations have been made. An application is presented in nuclear medicine experiences. In the case of a thyroid treatment with 131 I, the external dose workers have been evaluated

  4. Individual external monitoring system for gamma and X ray evaluation of the individual dose equivalent 'HP(10)', utilizing a photographic dosimetry technique

    International Nuclear Information System (INIS)

    Santoro, Christiana; Filho, Joao Antonio

    2008-01-01

    Full text: Individual monitoring evaluates external sources of ionizing radiation X, γ, β and n, to which workers are occupationally exposed, for ensuring safe and acceptable radiological conditions in their places of employment. The dose received by workers should attend the limits authorized by national regulatory organs. Nowadays, there are two radiometric unit systems, based on resolutions of the National Nuclear Energy Commission (NNEC) and the International Commission on Radiation Units and Measurements (ICRU); in the conventional (NNEC) system, the doses received by workers are evaluated through the individual dose H x , where dosemeters used on surface of thorax are calibrated in terms of air kerma; in the recent system (ICRU), the doses are evaluated through the individual dose equivalent H P (d), where dosemeters are calibrated in terms of dose from phantom. The recent system improves the method of evaluation, by taking into account the scattering effect and absorption of radiation in the human body. This work adapts a photographic dosimetry service to the recent ICRU publications, for evaluation of individual monitoring, in function of the individual dose equivalent H P (10) of strong penetrating radiation. For this, a methodology based on linear programming and determination of calibration curves is used for radiation capacities, wide (W) and narrow (N) spectra, as described by the International Organization for Standardization (ISO 4037-1, 1995). These calibration curves offer better accuracy in the determination of doses and energy, which will improve the quality of the service given to society. The results show that the values of individual dose equivalent, evaluated at intervals of 0.2 to 200 mSv, have lower significant uncertainties (10%) than those recommended by the ICRP 75, for individual monitoring; therefore, the evaluation system for developed doses attends the new recommendations proposed by International Commissions. From what has been

  5. Analytical approaches to and interpretations of data on time, rate, and cause of death of mice exposed to external gamma irradiation

    International Nuclear Information System (INIS)

    Grahn, D.; Sacher, G.A.; Lea, R.A.; Fry, R.J.M.; Rust, J.H.

    1978-01-01

    Young adult male and female mice of inbred strains, A, BALB/c, C57BL/6, and C57L, and B6CF 1 and F 2 hybrids were exposed to daily duration-of-life external 60 Co γ irradiation. Age at death was recorded, and most decedents were necropsied to ascertain occurrence of major types of tumors. Age- and cause-specific mortality or incidence rates were derived, and their regressions on age were fitted with polynomial equations by least-squares procedures. Age-specific and age-adjusted integrated lifetime risk in excess of the control population was expressed as the mortality ratio (irradiated/control). Linear and nonlinear functions and widely different life expectancies can be accommodated by this technique. These basic actuarial statistics provide a means for comparative analysis of dose-response functions, sex and genetic variables, relative vs. absolute risk, protraction or dose-rate factors, and major contributing causes of excess risk. They also provide a basis for extrapolation to man. As examples, life shortening in days per rad (4 days/100 rads accumulated) is generally independent of sex, genotype, and daily dose rate. The integrated average lifetime risk of death related to all tumors (0.025%/rad) is largely independent of sex, genotype and dose-rates <12 rads/day, despite the fact that tumor incidence varies by a factor of 2 to 3 among genotypes. At low exposure rates, tumor-related mortality accounts for 80% of the excess risk, and life shortening is a function only of accumulated dose, independent of dose rate below 12 rads/day. The radiobiological effectiveness for low daily exposure levels is less than that for single exposures by a factor of 5 to 10. Life shortening following low daily exposure rates is induced at the rate of .03 to .06 days/R for the mouse, which extrapolates to about 1 to 2 days/R for man

  6. SU-F-T-31: Shape and Isodose Distributions in Co60 HDR Brachytherapy for Different Utero-Vaginal Time Ratios

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez-Sprinberg, G [Faculty of Sciences, Montevideo, Montevideo (Venezuela, Bolivarian Republic of); Piriz, G [Hospital Pereyra Rossell, Montevideo, Montevideo (Venezuela, Bolivarian Republic of)

    2016-06-15

    Purpose: To optimize the dose in bladder and rectum and show the different shapes of the isodose volumes in Co60-HDR brachytherapy, considering different utero and vaginal sources dwell ratio times (TU:TV). Methods: Besides Ir192-HDR, new Co60-HDR sources are being incorporated. We considered different TU:TV times and computed the dosis in bladder, rectum and at the reference points of the Manchester system. Also, we calculated the isodose volume and shape in each case. We used a EZAG-BEBIG Co0.A86 model with TPS HDRplus3.0.4. and LCT42-7, LCT42-2(R,L) applicators. A reference dose RA= 1.00 Gy was given to the A-right point. We considered the TU:TV dwell time ratios 1:0.25, 1:0.33, 1:0.5, 1:1, 1:2, 1:3, and 1:4. Given TU:TV, the stop time at each dwell position is fixed for each applicator. Results: Increasing TU:TV systematically results in a decreasing of the dose in bladder and rectum, e.g. 9% and 27% reduction were found in 1:0.25 with respect to 1:1, while 12% and 34% increase were found in 1:4 with respect to 1:1. Also, the isodose volume parameters height (h), width (w), thickness (t) and volume (hwt) increased from the 1:0.25 case to the 1:4 value: hwt is 25% lower and 31% higher than the 1:1 reference volume in these cases. Also w decreased for higher TU:TV and may compromise the tumoral volume coverage, decreasing 17% in the 1:0.25 case compared to the 1:1 case. The shape of the isodose volume was obtained for the different TU:TV considered. Conclusion: We obtained the shape of isodose volumes for different TU:TV values in gynecological Co60-HDR. We studied the dose reduction in bladder and rectum for different TU:TV ratios. The volume parameters and hwt are strongly dependent on this ratio. This information is useful for a quantitative check of the TPS and as a starting point towards optimization.

  7. Gamma emitting radionuclides of the Test Reactor Area leaching ponds

    International Nuclear Information System (INIS)

    Millard, J.B.; Whicker, F.W.; Markham, O.D.

    1978-01-01

    Radioactive leaching ponds adjacent to the Test Reactor Area (TRA) located on the Idaho National Engineering Laboratory (INEL) Site were investigated to determine the seasonal distribution and ecological behavior of gamma emitting radionuclides. The potential hazards to man and the environment were considered through the biological export of radioactive materials from the ponds. Both biotic and abiotic pond compartments were sampled. Fall and winter biomass estimates showed that benthic periphyton comprised 52%, macrophytes and littoral vegetation 35%, and seston 10% of the total for all biotic compartments. Concentrations and concentration factors (CFs) for fall and winter are presented for Cr-51, Co-60, Zr-95, I-131, Cs-137, Ba-140, and Ce-141. Concentrations and CFs ranged over seven orders of magnitude for the various nuclides and compartments. Seston and zooplankton had the highest concentrations followed by periphyton, sediment, macrophytes, littoral plants, willow, and filtered water. Arthropods had variable concentrations and CFs. Significant seasonal differences were observed for concentrations and CFs in seston, macrophytes, and littoral vegetation. A compartmental inventory of total gamma emitting activity accounted for 254 Ci (9.25 TBq) of the 731 Ci (24.8 TBq) estimated to remain in the ponds at the time of sampling. Filtered water and surface sediments contained 99% of the total radioactivity, while periphyton and seston had most of the remaining 1%. An estimate of the avian export rate of radioactivity from the TRA ponds showed that potentially harvestable mourning doves had the lowest rate with 0.02 μCi/y. External tissues of migratory waterfowl were found to contribute 90% of the total exported activity for all birds. The total avian export rate was estimated to be 1350 μCi/y during 1975

  8. External dosimetry sources and shielding

    International Nuclear Information System (INIS)

    Calisto, Washington

    1994-01-01

    A definition of external dosimetry r external sources dosimetry,physical and mathematical treatment of the interaction of gamma radiation with a minimal area in that direction. Concept of attenuation coefficient, cumulated effect by polyenergetic sources, exposition rate, units, cumulated dose,shielding, foton shielding, depth calculation, materials used for shielding.Beta shielding, consideration of range and maximum β energy , low stopping radiation by use of low Z shielding. Tables for β energy of β emitters, I (tau) factor, energy-range curves for β emitters in aqueous media, gamma attenuation factors for U, W and Pb. Y factor for bone tissue,muscle and air, build-up factors

  9. SU-E-T-335: Dosimetric Investigation of An Advanced Rotating Gamma Ray System for Imaged Guided Radiation Therapy

    International Nuclear Information System (INIS)

    Ma, C; Eldib, A; Chibani, O; Li, J; Chen, L; Li, C; Mora, G

    2015-01-01

    Purpose: Co-60 beams have unique dosimetric properties for cranial treatments and thoracic cancers. The conventional concern about the high surface dose is overcome by modern system designs with rotational treatment techniques. This work investigates a novel rotational Gamma ray system for image-guided, external beam radiotherapy. Methods: The CybeRT system (Cyber Medical Corp., China) consists of a ring gantry with either one or two treatment heads containing a Gamma source and a multileaf collimator (MLC). The MLC has 60 paired leaves, and the maximum field size is either 40cmx40cm (40 pairs of 0.5cm central leaves, 20 pairs of 1cm outer leaves), or 22cmx40cm (32 pairs of 0.25cm central leaves, 28 pairs of 0.5cm outer leaves). The treatment head(s) can swing 35° superiorly and 8° inferiorly, allowing a total of 43° non-coplanar beam incident. The treatment couch provides 6-degrees-of-freedom motion compensation and the kV cone-beam CT system has a spatial resolution of 0.4mm. Monte Carlo simulations were used to compute dose distributions and compare with measurements. A retrospective study of 98 previously treated patients was performed to compare CybeRT with existing RT systems. Results: Monte Carlo results confirmed the CybeRT design parameters including output factors and 3D dose distributions. Its beam penumbra/dose gradient was similar to or better than that of 6MV photon beams and its isocenter accuracy is 0.3mm. Co-60 beams produce lower-energy secondary electrons that exhibit better dose properties in low-density lung tissues. Because of their rapid depth dose falloff, Co-60 beams are favorable for peripheral lung tumors with half-arc arrangements to spare the opposite lung and critical structures. Superior dose distributions were obtained for head and neck, breast, spine and lung tumors. Conclusion: Because of its accurate dose delivery and unique dosimetric properties of C-60 sources, CybeRT is ideally suited for advanced SBRT as well as

  10. SU-E-T-335: Dosimetric Investigation of An Advanced Rotating Gamma Ray System for Imaged Guided Radiation Therapy

    Energy Technology Data Exchange (ETDEWEB)

    Ma, C; Eldib, A; Chibani, O; Li, J; Chen, L [Fox Chase Cancer Center, Philadelphia, PA (United States); Li, C [Renmin Hospital of Wuhan University, Wuhan (China); Mora, G [Universidade de Lisboa, Codex, Lisboa (Portugal)

    2015-06-15

    Purpose: Co-60 beams have unique dosimetric properties for cranial treatments and thoracic cancers. The conventional concern about the high surface dose is overcome by modern system designs with rotational treatment techniques. This work investigates a novel rotational Gamma ray system for image-guided, external beam radiotherapy. Methods: The CybeRT system (Cyber Medical Corp., China) consists of a ring gantry with either one or two treatment heads containing a Gamma source and a multileaf collimator (MLC). The MLC has 60 paired leaves, and the maximum field size is either 40cmx40cm (40 pairs of 0.5cm central leaves, 20 pairs of 1cm outer leaves), or 22cmx40cm (32 pairs of 0.25cm central leaves, 28 pairs of 0.5cm outer leaves). The treatment head(s) can swing 35° superiorly and 8° inferiorly, allowing a total of 43° non-coplanar beam incident. The treatment couch provides 6-degrees-of-freedom motion compensation and the kV cone-beam CT system has a spatial resolution of 0.4mm. Monte Carlo simulations were used to compute dose distributions and compare with measurements. A retrospective study of 98 previously treated patients was performed to compare CybeRT with existing RT systems. Results: Monte Carlo results confirmed the CybeRT design parameters including output factors and 3D dose distributions. Its beam penumbra/dose gradient was similar to or better than that of 6MV photon beams and its isocenter accuracy is 0.3mm. Co-60 beams produce lower-energy secondary electrons that exhibit better dose properties in low-density lung tissues. Because of their rapid depth dose falloff, Co-60 beams are favorable for peripheral lung tumors with half-arc arrangements to spare the opposite lung and critical structures. Superior dose distributions were obtained for head and neck, breast, spine and lung tumors. Conclusion: Because of its accurate dose delivery and unique dosimetric properties of C-60 sources, CybeRT is ideally suited for advanced SBRT as well as

  11. The gamma-ray radiation preservation technology for files and books

    International Nuclear Information System (INIS)

    Fan Chengfa; Tian Kaizen; Zhang Yunlu; Gan Saohan; Wang Zhengfu; Xiang Jiafang

    1988-01-01

    In this paper, a radiation appliance using CO-60 Gamma-ray to preserve the files and books is introduced. The lump and transport radiation techniques for processing files and books with this radiation appliance is described. The cost of preserving files and books with this method has been estimated. Comparison of this method with other processing techniques has been taken. (author)

  12. Installation of the product transport system and control system for the Co-60 irradiator at the Institute of Investigations of the Alimentary Industry (IIIA), La Havana, Cuba

    International Nuclear Information System (INIS)

    Tran Khac An; Le Minh Tuan; Pham Thi Thu Hong; Nguyen Thanh Cuong; Huynh Dong Phuong; Ha Thanh Viet; Truong Vu Thanh Nhan

    2016-01-01

    Under the protocol of international cooperation in science and technology between Vietnam and Cuba - “Installation of the product transport system and control system for the Cobalt-60 irradiator at the Institute of Investigations of the Alimentary Industry (IIIA)”, the renovation of the irradiator has been started since 2012 and carried out by Research and Development Center for Radiation Technology (VINAGAMMA). The renovation work comprises the installation of the tote box transport system that was designed and constructed by Isotope Institute Budapest, Hungary, the installation of the PLC based control system which were designed and constructed by VINAGAMMA, installations of technological systems and training Cuban irradiator operators. The project has been successfully implemented and the industrial Co-60 irradiator with new control system has been put into operation. (author)

  13. The comparison between the humoral response and the neutralizing capacity of sheep serum inoculated with natural venom and Co60 irradiated venom from Crotalus durissus terrificus (Laurenti, 1768)

    International Nuclear Information System (INIS)

    Netto, D.P.

    2000-01-01

    Crotalus durissus terrificus venom was irradiated with Co 60 to investigate the effects of antigen-irradiation on antivenom production in sheep. Twelve sheep were divided in two groups of 6. One group received irradiated, while the other received natural venom. Three doses of antigen were given at monthly intervals. The toxic activity of the venom was assessed by LD 50 in mice. Weekly blood samples were obtained to evaluate anti-crotalic serum titers by indirect ELISA, neutralization capacity, and serum potency. A complete blood count, plasma protein and fibrinogen concentration, and serum albumin and globulin were also determined. At end of the experiment, the animals were challenged with ovine LD 50 , without clinical abnormalities. (author)

  14. SU-F-T-375: Optimization of a New Co-60 Machine for Intensity Modulated Radiation Therapy: A Monte Carlo Characterization Study

    Energy Technology Data Exchange (ETDEWEB)

    Chibani, O; Fan, J; Tahanout, F; Eldib, A; Ma, C [Fox Chase Cancer Center, Philadelphia, PA (United States)

    2016-06-15

    Purpose: To provide a wide range of dose output for intensity modulation purposes while minimizing the beam penumbra for a new rotating cobalt therapy system. The highest dose rate needs to be maximized as well. Methods: The GEPTS Monte Carlo system is used to calculate the dose distribution from each tested Co-60 head for a wide range of field sizes (1×1 to 40×40 cm2). This includes the transport of photons (and secondary electrons) from the source through the collimation system (primary collimator, Y and × jaws, and MLCs) and finally in the water phantom. Photon transport includes Compton scattering (with electron binding effect), Rayleigh scattering, Photoelectric effect (with detailed simulation of fluorescence x-rays). Calculations are done for different system designs to reduce geometric penumbra and provide dose output modulation. Results: Taking into account different clinical requirements, the choice of a movable head (SAD = 70 to 80 cm) is made. The 120-leaf MLC (6-cm thick) entrance is at 32 cm from the bottom of the source (to reduce penumbra while allowing larger patient clearance). Three system designs (refereed here as S1–3) were simulated with different effective source sizes (2mm, 10mm and 17mm diameter). The effective point source is at mid-height of the 25-mm-long source. Using a 12000-Ci source, the designed Co-60 head can deliver a wide range of dose outputs (0.5 − 4 Gy/mn). A dose output of 2.2 Gy/mn can be delivered for a 10cm × 10cm field size with 1-cm penumbra using a 10mm effective source. Conclusion: A new 60Co-based VMAT machine is designed to meet different clinical requirements in term of dose output and beam penumbra. Outcomes from this study can be used for the design of 60Co machines for which a renewed interest is seen.

  15. Borosilicate glass for gamma irradiation fields

    Science.gov (United States)

    Baydogan, N.; Tugrul, A. B.

    2012-11-01

    Four different types of silicate glass specimens were irradiated with gamma radiation using a Co-60 radioisotope. Glass specimens, with four different chemical compositions, were exposed to neutron and mixed neutron/gamma doses in the central thimble and tangential beam tube of the nuclear research reactor. Optical variations were determined in accordance with standardisation concept. Changes in the direct solar absorbance (αe) of borosilicate glass were examined using the increase in gamma absorbed dose, and results were compared with the changes in the direct solar absorbance of the three different type silicate glass specimens. Solar absorption decreased due to decrease of penetration with absorbed dose. αe of borosilicate increased considerably when compared with other glass types. Changes in optical density were evaluated as an approach to create dose estimation. Mixed/thermal neutron irradiation on glass caused to increse αe.

  16. Effects of gamma radiation in tomato seeds

    Energy Technology Data Exchange (ETDEWEB)

    Wiendl, Toni A.; Wiendl, Fritz W.; Franco, Suely S.H.; Franco, Jose G.; Althur, Valter, E-mail: tawiendl@hotmail.com, E-mail: gilmita@uol.com.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Arthur, Paula B., E-mail: arthur@cena.usp.br [Centro de Energia Nuclear na Agricultura (CENA/USP), Piracicaba, SP (Brazil)

    2013-07-01

    Tomato dry seeds of the hybrid 'Gladiador' F1 were exposed to low doses of gamma radiation from Co-60 source at 0,509 kGy tax rate in order to study stimulation effects of radiation on germination and plant growth. Eight treatments radiation doses were applied as follows: 0 (control); 2,5; 5,0; 7,5; 10,0; 12,5; 15,0; 20,0 Gy. Seed germination as well as green fruits number, harvested fruit number, fruit weight and total production were assessed to identify occurrence of stimulation. Tomato seeds and plants were handled as for usual tomato production in Brazil. Low doses of gamma radiation treatment in the seeds stimulate germination and substantially increase fruit number and total production up to 86% at 10 Gy dose. There are evidences that the use of low doses of gamma radiation can stimulate germination and plant production thus, showing hormetic effects. (author)

  17. Effects of gamma radiation in tomato seeds

    International Nuclear Information System (INIS)

    Wiendl, Toni A.; Wiendl, Fritz W.; Franco, Suely S.H.; Franco, Jose G.; Althur, Valter; Arthur, Paula B.

    2013-01-01

    Tomato dry seeds of the hybrid 'Gladiador' F1 were exposed to low doses of gamma radiation from Co-60 source at 0,509 kGy tax rate in order to study stimulation effects of radiation on germination and plant growth. Eight treatments radiation doses were applied as follows: 0 (control); 2,5; 5,0; 7,5; 10,0; 12,5; 15,0; 20,0 Gy. Seed germination as well as green fruits number, harvested fruit number, fruit weight and total production were assessed to identify occurrence of stimulation. Tomato seeds and plants were handled as for usual tomato production in Brazil. Low doses of gamma radiation treatment in the seeds stimulate germination and substantially increase fruit number and total production up to 86% at 10 Gy dose. There are evidences that the use of low doses of gamma radiation can stimulate germination and plant production thus, showing hormetic effects. (author)

  18. Gamma apparatuses for radiotherapy

    International Nuclear Information System (INIS)

    Sul'kin, A.G.

    1986-01-01

    Scientific and technical achievements in development and application of gamma therapeutic apparatuses for external and intracavity irradiations are generalized. Radiation-physical parameters of apparatuses providing usability of progressive methods in radiotherapy of onclogical patients are given. Optimization of main apparatus elements, ensurance of its operation reliability, reduction of errors of irradiation plan reproduction are considered. Attention is paid to radiation safety

  19. Distillation columns inspection through gamma scanning

    International Nuclear Information System (INIS)

    Garcia, Marco

    1999-09-01

    The application of nuclear energy is very wide and it allows the saving of economic resources since the investigation of a certain process is carried out without stop the plant. The gamma scanning of oil c racking c olumns are practical examples, they allow to determine the hydraulic operation of the inspected columns. A source of Co-60 22mCi and a detector with a crystal of INa(TI) are used. This paper shows the results got from a profile carried out in a column distillation

  20. Comparison of gamma, neutron and proton irradiations of multimode fibers

    International Nuclear Information System (INIS)

    Gingerich, M.E.; Dorsey, K.L.; Askins, C.G.; Friebele, E.J.

    1987-01-01

    The effects of pure gamma, pure proton, and mixed neutron-gamma irradiation fields on a set of both pure and doped silica core multimode fibers have been investigated. Only slight differences are found in the radiation response of pure and doped silica core fibers exposed to gamma or mixed neutron-gamma fields, indicating that Co-60 sources can be used to simulate the effects of the mixed field (except in the case of a pure neutron environment). Although it is noted that neither mix field nor gamma sources adequately simulate the effects of proton irradiation of doped silica core fibers, a good correspondence is found in the case of the pure silica core waveguide. 13 references

  1. Gamma-ray shielding design and performance test of WASTEF

    International Nuclear Information System (INIS)

    Matsumoto, Seiichiro; Aoyama, Saburo; Tashiro, Shingo; Nagai, Shiro

    1984-06-01

    The Waste Safety Testing Facility (WASTEF) was planned in 1978 to test the safety performance of HLW vitrified forms under the simulated conditions of long term storage and disposal, and completed in August 1981. The designed feature of the facility is to treat the vitrified forms contain actual high-level wastes of 5 x 10 4 Ci in maximum with 5 units of concrete shilded hot cells (3 units : Bate-Gamma cells, 2 units : Alpha-Gamma cells) and one units of Alpha-Gamma lead shielded cell, and to store radioactivity of 10 6 Ci in maximum. The safety performance of this facility is fundamentally maintained with confinement of radioactivity and shielding of the radiation. This report describes the method of gamma-ray shielding design, evaluation of the shielding test performed by using sealded gamma-ray sources(Co-60). (author)

  2. SU-F-T-317: Skin Exposure Outside the Treatment Field During Treatment of Breast Cancer with Tri-Co-60 MR-IGRT System

    Energy Technology Data Exchange (ETDEWEB)

    Park, J; Kim, J; Park, S [Seoul National University Hospital, Seoul (Korea, Republic of); Kim, S [Nuclear Safety and Security Commission, Seoul (Korea, Republic of); Shin, K [Seoul National University College of Medicine, Seoul (Korea, Republic of)

    2016-06-15

    Purpose: To investigate exposure outside the treatment field when treating breast cancer with tri-Co-60 magnetic resonance (MR) image guided radiation therapy (IGRT) system. Methods: A total of 7 patients who treated with accelerated partial breast irradiation (APBI) technique were selected prospectively for this study (prescription dose = 38.5 Gy in 10 fractions). Every patient treated with two plans, one was an initial plan and the other was an adaptive plan generated after finishing 5 fractions (a total of 14 plans). Every plan was calculated with and without magnetic field in the treatment planning system. The EBT3 films were attached on the front and the back of 1 cm bolus, and then it was placed on the patient body vertically to cover patient’s jaw and shoulder. After measurements, the maximum point dose and the mean dose of whole area of EBT3 film were acquired. Results: In the treatment plan with magnetic field, low dose stream outside the patient body was observed, almost reaching the patient’s jaw or shoulder, while it was not observed without magnetic field. The average values of the measured maximum and mean doses at the front of bolus were 30.1 ± 11.1 cGy (7.8% of the daily dose) and 14.7 ± 3.3 cGy (3.8%), respectively. At the back of bolus, those values were 6.0 ± 1.9 cGy (1.6%) and 5.1 ± 1.6 cGy (1.3%), respectively. The largest maximum dose at the front was 54.2 cGy (14.1%) while it was 20.7 cGy (5.4%) at the back. The average decrease of the maximum dose by the bolus was 24.0 ± 11.0 cGy. Conclusion: Due to magnetic field, dose stream outside the patient body can be generated during breast cancer treatment with the tri-Co-60 MR-IGRT system. Since this dose stream irradiated skin outside the treatment field, it should be shielded. This work was supported by the National Research Foundation of Korea (NRF) grant funded by the Korea government (MSIP) (No. 2015R1C1A1A01054192).

  3. Dosimetric comparison on tissue interfaces with TLD dosimeters, L-alanine, EDR2 films and Penelope simulation for a Co-60 source and linear accelerator in radiotherapy

    International Nuclear Information System (INIS)

    Vega R, J. L.; Cayllahua, F.; Apaza, D. G.; Javier, H.

    2015-10-01

    Percentage depth dose curves were obtained with TLD-100 dosimeters, EDR2 films and Penelope simulation at the interfaces in an inhomogeneous mannequin, composed by equivalent materials to the human body built for this study, consisting of cylindrical plates of solid water-bone-lung-bone-solid water of 15 cm in diameter and 1 cm in height; plates were placed in descending way (4-2-8-2-4). Irradiated with Co-60 source (Theratron Equinox-100) for small radiation fields 3 x 3 cm 2 and 1 x 1 cm 2 at a surface source distance of 100 cm from mannequin. The TLD-100 dosimeters were placed in the center of each plate of mannequin irradiated at 10 Gy. The results were compared between these measurement techniques, giving good agreement in interfaces better than 97%. This study was compared with the same characteristics of another study realized with other equivalent materials to human body not homogeneous acrylic-bone-cork-bone-acrylic. The percentage depth dose curves were obtained with mini-dosimeters L-alanine of 1 mm in diameter and 3 mm in height and 3.5 to 4.0 mg of mass with spectrometer band K (EPR). The mini-dosimeters were irradiated with a lineal accelerator PRIMUS Siemens 6 MV. The results of percentage depth dose of L-alanine mini-dosimeters show a good agreement with the percentage depth dose curves of Penelope code, better than 97.7% in interfaces of tissues. (Author)

  4. Thermoluminescent response of aluminium oxide thin films subject to gamma irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Arrieta, A.; Escobar A, L.; Camps, E.; Villagran, E.; Gonzalez, P.R

    2006-07-01

    The thermoluminescent (TL) properties of amorphous aluminium oxide thin films (thicknesses as low as 0.3 {mu}m) subjected to gamma (Co-60) irradiation are reported. Aluminium oxide thin films were prepared by laser ablation from an Al{sub 2}O{sub 3} target using a Nd: YAG laser with emission at the fundamental line. The films were exposed to gamma radiation (Co-60) in order to study their TL response. Thermoluminescence glow curves exhibited two peaks at 110 and 176 C. The high temperature peak shows good stability and 30% fading in the first 5 days after irradiation. A linear relationship between absorbed dose and the thermoluminescent response for doses span from 150 mGy to 100 Gy was observed. These results suggest that aluminium oxide thin films are suitable for detection and monitoring of gamma radiation. (Author)

  5. Behavior of the dynamic magnetic susceptibility in ybco bula ceramics irradiated with gamma rays

    International Nuclear Information System (INIS)

    Leyva Fabelo, A.; Bouza Dominguez, J.; Cruz Inclan, Carlos M.

    2001-01-01

    Using measurements of the ac susceptibility, the behavior with the irradiation dose of YBa2Cu3O7- bulk ceramics synthesized by the classic reaction method in solid state, was studied. A Co60 gamma chamber model MPX-G-25M and a Cs137 source were employed as gamma ray sources. The behavior of the beginning temperature of the normal - superconducting state transition with the exposition dose show, independently of the incident gamma energy, a monotonous growth until reaching a threshold dose, after which, observe a fall, more abrupt in the case of the Co60. This behavior can be explained using the model that postulates the ability of the gamma radiation, in certain dose intervals, to stimulate the structural reordering in the oxygen sublattice. When the irradiation process takes place in the Co60 gamma chamber, the behavior of the superconducting volume fraction of the sample characterizes by the initial sharp fall with the dose, followed with an attenuation of the decrement. In the case of Cs137 irradiation, the behavior of the superconducting volume fraction is similar to the behavior of the Ton with the dose

  6. Gamma irradiation technology for composite materials

    International Nuclear Information System (INIS)

    Romero, Guillermo R; Gonzalez, Maria E.

    2003-01-01

    A composite of sugar cane bagasse and low-density polyethylene was prepared. Gamma -radiation of Cobalt-60 (Co 60 ) and reactive additives were used, to make compatible the lignocellulosic fibers with the polymeric matrix. Gamma-radiation was applied in different stages with different purposes: a) Irradiation of cellulosic fibers treated or not with reactive additive, in presence of air, to produce macro radicals increasing their reactivity during extrusion with polyethylene. A homogeneous and fusible material resulted that can be used as raw material in thermoforming processes with cost in between that of its constitutive elements; b) Irradiation of final products, to produce the cross-linking of polymeric chains. The fibers remain trapped in the cross-linked matrix. A homogeneous and infusible material with high mechanical properties was obtained. (author)

  7. Gamma Knife

    Science.gov (United States)

    ... News Physician Resources Professions Site Index A-Z Gamma Knife Gamma Knife® is a radiation therapy that uses computerized ... If you're scheduled for radiation therapy using Gamma Knife®, a treatment team consisting of a radiation ...

  8. Effect of the gamma irradiation on the bio-sorption of Cr (Vi) by orange peel

    International Nuclear Information System (INIS)

    Lugo L, V.; Barrera D, C. E.; Sanchez M, V.; Urena N, F.

    2009-01-01

    The orange peel (Citrus sp.) is a bioadsorbent that contains functional groups able to remove Cr (Vi). To study the effect of gamma irradiation in the sorption capacity, the Nn materials were irradiated with gamma rays using a Co 60 source to dose from 10 to 3500 KGy (Nlγ). The biomass irradiation with gamma rays was successful since it increased the hexavalent chromium removal obtaining a maximum removal percentage of 100%. Sorption isotherms were realized to determine the concentration effect of initial Cr (Vi), the ph effect of the solution and the relationship m/v. (Author)

  9. Conceptual design of gamma irradiator (ISG-500) for preservation of farming product

    International Nuclear Information System (INIS)

    S Budihardjo; Dian F Atmoko; Syamsurijjal Ramja; Sutomo; A Suntoro; Pudjijanto MS; Nada Mamada

    2010-01-01

    A conceptual design of gamma irradiator ISG-500 for a preservation of farming product has been done. The design of gamma irradiator are multi purpose with the activity of radiation source used at 2x250 kCi cobalt-60. This gamma irradiator will be built by using local materials, like as for the building structure construction, the mechanical and electrical systems and for the instrumentation and control systems. The sources of radiation that will be used is Co60 pencil types (C 188 - Nordion), concrete structured building according to BAPETEN rule and the numbers of carriers that will be used are 15 carriers. (author)

  10. SU-F-T-347: An Absolute Dose-Volume Constraint Based Deterministic Optimization Framework for Multi-Co60 Source Focused Radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Liang, B; Liu, B; Li, Y; Guo, B; Xu, X; Wei, R; Zhou, F [Beihang University, Beijing, Beijing (China); Wu, Q [Duke University Medical Center, Durham, NC (United States)

    2016-06-15

    Purpose: Treatment plan optimization in multi-Co60 source focused radiotherapy with multiple isocenters is challenging, because dose distribution is normalized to maximum dose during optimization and evaluation. The objective functions are traditionally defined based on relative dosimetric distribution. This study presents an alternative absolute dose-volume constraint (ADC) based deterministic optimization framework (ADC-DOF). Methods: The initial isocenters are placed on the eroded target surface. Collimator size is chosen based on the area of 2D contour on corresponding axial slice. The isocenter spacing is determined by adjacent collimator sizes. The weights are optimized by minimizing the deviation from ADCs using the steepest descent technique. An iterative procedure is developed to reduce the number of isocenters, where the isocenter with lowest weight is removed without affecting plan quality. The ADC-DOF is compared with the genetic algorithm (GA) using the same arbitrary shaped target (254cc), with a 15mm margin ring structure representing normal tissues. Results: For ADC-DOF, the ADCs imposed on target and ring are (D100>10Gy, D50,10, 0<12Gy, 15Gy and 20Gy) and (D40<10Gy). The resulting D100, 50, 10, 0 and D40 are (9.9Gy, 12.0Gy, 14.1Gy and 16.2Gy) and (10.2Gy). The objectives of GA are to maximize 50% isodose target coverage (TC) while minimize the dose delivered to the ring structure, which results in 97% TC and 47.2% average dose in ring structure. For ADC-DOF (GA) techniques, 20 out of 38 (10 out of 12) initial isocenters are used in the final plan, and the computation time is 8.7s (412.2s) on an i5 computer. Conclusion: We have developed a new optimization technique using ADC and deterministic optimization. Compared with GA, ADC-DOF uses more isocenters but is faster and more robust, and achieves a better conformity. For future work, we will focus on developing a more effective mechanism for initial isocenter determination.

  11. Gamma Irradiation on Growth and Development of Amorphophallus muelleri Blume.

    Directory of Open Access Journals (Sweden)

    Edi Santosa

    2014-09-01

    Full Text Available ABSTRACT Iles-iles (Amorphophallus muelleri Blume produces apomictic seeds lead to low genetic variation. In order to induce genetic variation, germinated seeds were exposed to Gamma irradiation (Co-60 at doses of 10 to 100 Gy. Seed irradiation was conducted at Center for the Application of Isotope and Irradiation Technology -National Nuclear Energy Agency (CAIRT, Indonesia. Morphology and yield of M1 generation were observed. Results showed that irradiation at a dose of 10 Gy close to LD50 with survival rate 56%. Gamma irradiation at a dose of 10 Gy delayed seeds germination.  Germination rates gradually increased and reached maximum at 4 weeks after planting (WAP for control plants, and 14 WAP of irradiated plants. At 16 WAP, germination rate of 10 Gy irradiated plants was 56% and 84% for those of control plants. Irradiation induced chimera as indicated by short petiole, variegated and abnornal shape of leaflets. Some irradiated plants entered dormancy at 8-10 weeks later than control ones. Prolong vegetative periode lead the plants to produce heavier corms. This study revealed the possibility to induce variation of A. muelleri by using gamma irradition. Keywords: Amorphophallus muelleri, gamma irradiation (Co-60, morphological variation, mutation breeding

  12. Gamma and Proton-Induced Dark Current Degradation of 5T CMOS Pinned Photodiode 0.18 mu{m} CMOS Image Sensors

    Science.gov (United States)

    Martin, E.; Nuns, T.; David, J.-P.; Gilard, O.; Vaillant, J.; Fereyre, P.; Prevost, V.; Boutillier, M.

    2014-02-01

    The radiation tolerance of a 0.18 μm technology CMOS commercial image sensor has been evaluated with Co60 and proton irradiations. The effects of protons on the hot pixels and dynamic bias and duty cycle conditions during gamma irradiations are studied.

  13. The possibility of gamma ray sterilization by using ITU TRIGA Mark II reactor

    International Nuclear Information System (INIS)

    Bilge, A.N.; Tugrul, B.; Yavuz, H.

    1988-01-01

    Gamma rays are one of the effective method for sterilization which is preferred for a long time. Generally Co-60 radioisotope sources betatrons or accelerators are used for the sterilization. In this work, it was aimed to find the possibilities of the sterilization by gamma rays obtained in ITU TRIGA Mark-II radial tube. Radiation dosages are measured in the radial tube and several medical products are irradiated. Irradiation is arranged according to the desired dosages. Irradiated sterilized goods (mainly medical products) tested and checked at the Governmental Medical Health Center and results compared with literature. It can be seen that this kind of irradiation is a good tool for sterilization. Unfortunately, because of the stability of the radial tube and impracticality of the system it is rather difficult to compete with industrial system using Co-60 and accelerators. Nevertheless, this type of irradiation is also applicable for the purpose of the sterilization by using ITU TRIGA Mark II. (author)

  14. Hydrogel wound dressing preparation at the laboratory scale by using electron beam and gamma radiation

    International Nuclear Information System (INIS)

    Rapado Raneque, Manuel; Rodriguez Rodriguez, Alejandro; Peniche Covas, Carlos

    2013-01-01

    The present work describes the preparation of hydrogel based on cross-linked networks of poly (N-vinylpirrolidone), PVP, with polyethyleneglicol and agar with 90% water and PVP nancomposites with a synthetic nanoclay, Laponite XLG, for use as burn dressings. These systems were obtained in two ways: using gamma Co-60 and electron beam radiation. The gelation obtained dose was D g = 1.72 kGy. The elastic modulus of hydrogel was independent of the method of irradiation. It was 0.39 MPa for the hydrogel irradiated with gamma Co-60 and 0.38 MPa for electron beam irradiation. The elastic modulus of the nanocomposite membrane was 1.25 MPa, three times higher. These results indicate that the PVP/Laponite XLG nanocomposite hydrogel membrane is the best choice for wound dressing applications due to its high water sorption capacity and its superior mechanical properties.

  15. Comparative effectiveness of gamma-rays and electron beams in food irradiation

    International Nuclear Information System (INIS)

    Hayashi, Toru

    1991-01-01

    Ionizing radiations which can be used for the treatment of foods are gamma-rays from Co-60 and Cs-137, accelerated electrons from a machine at an energy of 10 MeV or lower and X-rays from a machine at an energy of 5 MeV or lower. The Joint FAO/IAEA/WHO Expert Committee on the Wholesomeness of Irradiated Food held in 1980 concluded that the foods irradiated at overall average doses up to 10 kGy with the radiation listed above are wholesome for human consumption. While most of the commercial food irradiations are conducted with gamma-rays from Co-60, accelerated electrons are increasingly utilized for treating foods. An important difference between gamma-rays and accelerated electrons is the penetration capacity in materials. The penetration capacity of gamma-rays is much higher than that of accelerated electrons. Another important difference is the dose rate. The dose rates of gamma-rays from commercial Co-60 sources are 1-100 Gy/min, while those of electron beams from electron accelerators are 10 3 -10 6 Gy/s. Ideally a comparison of the effect of different types of ionizing radiation should be carried out at the same dose rate but this has been difficult due to the design of irradiators. It is very difficult to draw a definite conclusion on the difference in the effectiveness in food irradiation between gamma-rays and electron beams based on published data. This chapter deals with as many reports as possible on the comparative effectiveness of gamma-rays and electron beams and on the effect of dose rate on chemical reactions and living organisms, whether or not they demonstrate any dependency of the effect of irradiation on dose rate and type of radiation. (author)

  16. Dosimetric comparison on tissue interfaces with TLD dosimeters, L-alanine, EDR2 films and Penelope simulation for a Co-60 source and linear accelerator in radiotherapy; Comparacion dosimetrica en interfaces de tejidos con dosimetros TLD, L-alanina, peliculas EDR2 y simulacion Penelope para una fuente de Co-60 y acelerador lineal en radioterapia

    Energy Technology Data Exchange (ETDEWEB)

    Vega R, J. L.; Cayllahua, F.; Apaza, D. G.; Javier, H., E-mail: josevegaramirez@yahoo.es [Universidad Nacional de San Agustin, Departamento de Fisica, Av. Independencia s/n, Arequipa (Peru)

    2015-10-15

    Percentage depth dose curves were obtained with TLD-100 dosimeters, EDR2 films and Penelope simulation at the interfaces in an inhomogeneous mannequin, composed by equivalent materials to the human body built for this study, consisting of cylindrical plates of solid water-bone-lung-bone-solid water of 15 cm in diameter and 1 cm in height; plates were placed in descending way (4-2-8-2-4). Irradiated with Co-60 source (Theratron Equinox-100) for small radiation fields 3 x 3 cm{sup 2} and 1 x 1 cm{sup 2} at a surface source distance of 100 cm from mannequin. The TLD-100 dosimeters were placed in the center of each plate of mannequin irradiated at 10 Gy. The results were compared between these measurement techniques, giving good agreement in interfaces better than 97%. This study was compared with the same characteristics of another study realized with other equivalent materials to human body not homogeneous acrylic-bone-cork-bone-acrylic. The percentage depth dose curves were obtained with mini-dosimeters L-alanine of 1 mm in diameter and 3 mm in height and 3.5 to 4.0 mg of mass with spectrometer band K (EPR). The mini-dosimeters were irradiated with a lineal accelerator PRIMUS Siemens 6 MV. The results of percentage depth dose of L-alanine mini-dosimeters show a good agreement with the percentage depth dose curves of Penelope code, better than 97.7% in interfaces of tissues. (Author)

  17. Effect of gamma radiation on garlic storage under natural conditions

    International Nuclear Information System (INIS)

    Ayyoubi, Zouhair; Sharabi, N.E.

    1993-02-01

    Garlic cloves were exposed to 30, 60, and 100 Gy of gamma radiation using Co 60 as a sources, to study the effect of different doses on the sprout inhibition of garlic. All the doses applied were effective. No sprout occurred in any of the treatments subjected to natural storage conditions. The effect of irradiation was evident in limiting the weight decrease. It reached 12 - 19% in 1987 and 1988 experiments respectively after 320 days of storage. Irradiation had no effect on the garlic consumptive specifications compared to the control. (author). 4 refs., 2 figs., 5 tabs

  18. Conversion of lignocellulosic waste by gamma irradiation and fungal fermentation

    International Nuclear Information System (INIS)

    Le Xuan Tham; Nguyen Duy Hang; Tran Huu Do; Hoang Thi My Linh; Nguyen Duy Lam

    2000-01-01

    Effects of microbial elimination (initially contaminated bacteria and fungi) were confirmed at wide range of irradiation doses (15-30 kGy) with gamma rays of Co-60 for substrates with sawdusts, sugar cane baggasse, rice straw, oil palm fibre and others. Some changes of main components of basic polysaccharides and nitrogen sources in substrates under irradiation and fermentations have been examined to confirm effective conversions and assimilations of inorganic nitrogen into protein, particularly using N-15 tracer techniques. Biomass obtained by fungal fermentations would be used for animal feed and spent compots were useful for biofertilizer production. (author)

  19. Report on salvage of a jammed cobalt-60 source of the gamma beam irradiator at Bangladesh Institute of Nuclear Agriculture (BINA), Mymensingh, Bangladesh

    International Nuclear Information System (INIS)

    Karim, S.M.F.; Awal, K.O.; Ali, M.A.T.

    1997-01-01

    This report is the follow-up of a recovery plan for a Co-60 source that was presented at the proceedings of a symposium at the International Atomic Energy Agency, Vienna during 6-10 November 1989. This report deals mainly with technical measures adopted to salvage the jammed Co-60 source of a gamma irradiator at the Bangladesh Institute of Nuclear Agriculture BINA, Mymensingh, Bangladesh. Different tools and devices were developed to allow the remote recovery of the source. The radiation safety measures taken and the device drawings are given, together with suggestions for future use of the source with the remaining activity for irradiation purposes. (author)

  20. Gamma astronomy

    International Nuclear Information System (INIS)

    Cesarsky, C.; Cesarsky, J.P.

    1986-01-01

    This article overviews the gamma astronomy research. Sources already observed, and what causes to give to them; the galactic radiation and its interpretation; techniques already used and current projects [fr

  1. Gamma Spectroscopy

    NARCIS (Netherlands)

    Niemantsverdriet, J.W.; Butz, Tilman; Ertl, G.; Knözinger, H.; Schüth, F.

    2008-01-01

    No abstract. The sections in this article are 1 Introduction 2 Mössbauer Spectroscopy 3 Time-Differential Perturbed Angular Correlations (TDPAC) 4 Conclusions and Outlook Keywords: Mössbauer spectroscopy; gamma spectroscopy; perturbed angular correlation; TDPAC

  2. 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

  3. Ageing effects in As10Se90 chalcogenide glasses induced by gamma-irradiation

    International Nuclear Information System (INIS)

    Golovchak, R.; Shpotyuk, O.; Shpotyuk, M.; Gorecki, Cz.; Kozdras, A.

    2005-01-01

    The peculiarities of gamma-induced (Co 60 source, 1.85 MGy absorbed dose) ageing phenomena in As 10 Se 90 chalcogenide glasses are investigated for the first time. The analogy between the observed radiation-induced ageing and the thermally induced one in vitreous selenium is emphasized. Like to thermal treatment, gamma-irradiation leads to an increase in the glass transition temperature and the relaxation rate towards a thermodynamic equilibrium of supercooled liquid, the value of this increase being greater in the case of radiation influence

  4. Elaboration of Co-60 sources on gilding vyns, with beta efficiencies 80 % or better and its activity measure by the coincidences method; Elaboracion de fuentes de Co-60 sobre vyns dorado, con eficiencias beta del 80 % o mejor y su medida de actividad por el metodo de coincidencias

    Energy Technology Data Exchange (ETDEWEB)

    Cortes P, A.; Tejera R, A.; Becerril V, A.; Ortiz C, A

    1991-12-15

    The measuring technique of radioactive activity by the coincidences method 4 {pi} {beta}{sup -} {gamma} it requires of the elaboration of radioactive sources on thin supports in order to flows the biggest percentage of beta particles, those of the order of the 80 % or but. In this work a procedure for the elaboration of this type of sources, with gilding Vyns is reported. (Author)

  5. Monte Carlo based demonstration of sufficiently dimensioned shielding for a Co-60 testing facility; Monte-Carlo-basierter Nachweis der ausreichend dimensionierten Abschirmung einer {sup 60}Co-Pruefanlage

    Energy Technology Data Exchange (ETDEWEB)

    Wind, Michael; Beck, Peter; Latocha, Marcin [Seibersdorf Labor GmbH, Radiation Protection Dosimetry, Seibersdorf (Austria)

    2015-07-01

    The electrical properties of electronic equipment can be changed in an ionized radiation field. The knowledge of these changes is necessary for applications in space, in air traffic and nuclear medicine. Experimental tests will be performed in Co-60 radiation fields in the irradiation facility (TEC facility) of the Seibersdorf Labor GmbH that is in construction. The contribution deals with a simulation that is aimed to calculate the local dose rate within and outside the building for demonstration of sufficient dimensioning of the shielding in compliance with the legal dose rate limits.

  6. Comparison of absorbed-dose-to-water units for Co-60 and high-energy x-rays between PTB and LNE-LNHB

    International Nuclear Information System (INIS)

    Delaunay, F.; Gouriou, J.; Le Roy, M.; Ostrowsky, A.; Sommier, L.; Vermesse, D.; Kapsch, R.P.; Illemann, J.; Krauss, A.

    2012-01-01

    During the Euramet project JRP7 'External Beam Cancer Therapy', PTB and LNE-LNHB used primary standards to determine the absorbed dose to water under IMRT conditions (in small fields). PTB used a water calorimeter to determine the absorbed-dose-to-water references in 6 MV and 10 MV beams for field sizes of 10 cm * 10 cm and 3 cm * 3 cm while LNE-LNHB used graphite calorimeters in 6MV and 12MV beams for field sizes of 10 cm * 10 cm, 4 cm * 4 cm and 2 cm * 2 cm. The purpose of this study is to compare PTB and LNE-LNHB new absorbed-dose-to-water references. LNE-LNHB sent an Exradin A1SL ionization chamber traceable to its primary standard to the PTB for calibration in 60 Co and in linac beams and PTB sent a PTW 31010 ionization chamber traceable to its primary standard to LNE-LNHB for calibration in 60 Co and in linac beams. Calculated Sw,air will be used as beam quality specifier for the ionization chamber comparison at different field sizes. The standard uncertainties (k = 1) of PTB and LNE-LNHB calibration coefficients lie respectively between 0.25% ( 60 Co) and 0.40% (linac) and between 0.29% and 0.46%. PTB and LNE-LNHB absorbed-dose-to-water references developed for this project, based respectively on water calorimetry and on graphite calorimetry, agree within 1.5 standard deviations for field size of 10 cm * 10 cm down to 2 cm * 2 cm and for beams of 6 MV to 10 MV. (authors)

  7. Gamma Irradiation Induced Degradation of Orange Peels

    Directory of Open Access Journals (Sweden)

    Jaime Saucedo Luna

    2012-08-01

    Full Text Available In this study, gamma irradiation induced degradation of orange peels (OP was investigated. The lignocellulosic biomass degradation was carried out at doses of 0 (control, 600, 1800 and 3500 kGy using a Co-60 gamma radiation source. The samples were tested for total and reducing sugars. The concentrations of total sugars ranged from 0.530 g∙g−1 in control sample to 0.382 g∙g−1 of dry weight in the sample which received the highest radiation dose. The reducing sugars content varying from 0.018 to 0.184 g∙g−1 of dry weight with the largest rise occurring in the sample irradiated at 3500 kGy. The concentrations of sucrose, glucose and fructose were determined. The changes generated in physico-chemical properties were determined by Fourier Transform Infrared Spectroscopy (FTIR and termogravimetric analysis (TG-DTG. The results show that OP was affected, but not significantly, which suggests that lignocellulose and sugars profiles were partially degraded after gamma irradiation.

  8. Gamma ray irradiation characteristics of SM fibers

    International Nuclear Information System (INIS)

    Ito, Ryuichi; Okano, Hiroaki; Hashiba, Keichi; Nakai, Hisanori

    1987-01-01

    1.3 μm range single mode (SM) optical fibers have been used for wide application of mainly long distance communication. At present, in order to realize the larger capacity and longer distance between relay points, the development of 1.5 μm range SM fibers of low dispersion and small loss has been actively promoted. As for the radiation withstanding property of SM fibers, report is scarce. The authors reported on the gamma ray irradiation characteristics of 1.3 μm range SM fibers, but since 1.5 μm range SM fibers are designed with the different structure from that of 1.3 μm fibers, it is necessary to evaluate from new viewpoint. In this report, mainly on the structure having triangular distribution, the effect that the manufacturing condition and the structural defects of glass exert on the gamma ray irradiation characteristics is described. The specimens were mainly dispersion shift type fibers (DSF), and for comparison, single window, double window and 1.3 μm SM fibers were examined. Co-60 gamma ray was irradiated, and the optical loss and electron spin resonance were measured. By low temperature and low speed drawing, the good result in the optical loss was obtained. The presence of oxygen at the time of sintering materials had no effect. The dependence of the ESR on the drawing condition was not very remarkable. (Kako, I.)

  9. Apparatus for gamma radiography

    International Nuclear Information System (INIS)

    1983-06-01

    The aim of the present standard is to fix the rules for the construction of gamma radiography instrumentation without prejudice to the present regulations. These apparatus have to be fitted with only sealed sources conformable to the experimental standard M 61-002. The present standard agrees with the international standard ISO 3999 of 1977 dealing with the same subject. Nevertheless, it is different on the three main following points: it does not accept the same limits of absorbed dose rates in the air calculated on the external surface of projectors; it precribes tightness, bending, crushing and tensile tests for some components of the gamma radiography it prescribes tests of endurance and resistance to breaking for the locking systems of the gamma radiography apparatus. The present standard also specifies the following points: symbols and indications to put on projectors and on the source-holder; identification of the source contained in the projector; and, accompanying documents. The regulation references are given in annexe [fr

  10. Gamma camera

    International Nuclear Information System (INIS)

    Berninger, W.H.

    1975-01-01

    The light pulse output of a scintillator, on which incident collimated gamma rays impinge, is detected by an array of photoelectric tubes each having a convexly curved photocathode disposed in close proximity to the scintillator. Electronic circuitry connected to outputs of the phototubes develops the scintillation event position coordinate electrical signals with good linearity and with substantial independence of the spacing between the scintillator and photocathodes so that the phototubes can be positioned as close to the scintillator as is possible to obtain less distortion in the field of view and improved spatial resolution as compared to conventional planar photocathode gamma cameras

  11. Effect of gamma irradiation on the protein, amino acids and carbohydrate contents of soya-gari diet

    International Nuclear Information System (INIS)

    Ogbadu, G.H.

    1979-01-01

    Soya-gari diet, prepared by enrichment of gari (Manihot esculanta Cranz) with soya flour, methionine, lysine and salt mixture was irradiated with doses of 62.5, 125, 250 and 500 Krad from a Co 60 γ irradiator. Gamma irradiation of the soya-gari diet with doses as high as 500 Krad had no significant effect on the amino acids, total proteins, soluble carbohydrates, hemicelluloses, cellulose and lignin contents. (author)

  12. Radiation effect on silicon transistors in mixed neutrons-gamma environment

    Science.gov (United States)

    Assaf, J.; Shweikani, R.; Ghazi, N.

    2014-10-01

    The effects of gamma and neutron irradiations on two different types of transistors, Junction Field Effect Transistor (JFET) and Bipolar Junction Transistor (BJT), were investigated. Irradiation was performed using a Syrian research reactor (RR) (Miniature Neutron Source Reactor (MNSR)) and a gamma source (Co-60 cell). For RR irradiation, MCNP code was used to calculate the absorbed dose received by the transistors. The experimental results showed an overall decrease in the gain factors of the transistors after irradiation, and the JFETs were more resistant to the effects of radiation than BJTs. The effect of RR irradiation was also greater than that of gamma source for the same dose, which could be because neutrons could cause more damage than gamma irradiation.

  13. Dosimetry characteristics of the Leksell gamma knife for stereotactic radiosurgery

    International Nuclear Information System (INIS)

    Wu, A.; Lindner, G.; Maitz, A.; Smarra, N.; Turco, R.F.; Kalend, A.M.; Lunsford, L.D.; Flickinger, J.C.; Bloomer, W.D.

    1988-01-01

    Gamma knife radiosurgery refers to the treatment procedure that delivers very high dose to a small brain lesion with 201 highly focused beams of Co-60. The hemispheric array of these multiple sources with the sizes of beams ranging from 4, 8, 14, to 18 mm makes the determination of dosimetry characteristics of the radiation field very complex. This paper describes the structures, operations, and dose characteristics of gamma knife. Dosimetry measurements were made using ion chamber, TLD, diode, and films to calibrate the dose outputs of the combination of 201 beams of 4, 8, 14, or 18 mm in diameter irradiating from various directions. Results of measured isodose distribution and dose profiles for the various diameter beams are also presented

  14. A conceptual gamma shield design using the DRP model computation

    Energy Technology Data Exchange (ETDEWEB)

    Ahmad, E E [Reactor Department, Nuclear Research Center, Atomic Energy Authority, Cairo (Egypt); Rahman, F A [National Center of Nuclear Safety and Radiation Control, Atomic Energy Authority, Cairo (Egypt)

    1997-12-31

    The purpose of this investigation is to assess basic areas of concern in the development of reactor shielding conceptual design calculations. A spherical shield model composed of low carbon steel and lead have been constructed to surround a Co-60 gamma point source. two alternative configurations have been considered in the model computation. The numerical calculations have been performed using both the ANISN code and DRP model computation together with the DLC 75-Bugle 80 data library. A resume of results for deep penetration in different shield materials with different packing densities is presented and analysed. The results showed that the gamma fluxes attenuation is increased with increasing distribution the packing density of the shield material which reflects its importance of considering it as a safety parameter in shielding design. 3 figs.

  15. Pocket PC-based portable gamma-ray spectrometer

    Directory of Open Access Journals (Sweden)

    Kamontip Ploykrachang

    2011-04-01

    Full Text Available A portable gamma-ray spectrometer based on a Pocket PC has been developed. A 12-bit pipeline analog-to-digitalconverter (ADC associated with an implemented pulse height histogram function on field programmable gate array (FPGAoperating at 15 MHz is employed for pulse height analysis from built-in pulse amplifier. The system, which interfaces withthe Pocket PC via an enhanced RS-232 serial port under the microcontroller facilitation, is utilized for spectrum acquisition,display and analysis. The pulse height analysis capability of the system was tested and it was found that the ADC integralnonlinearity of ±0.45% was obtained with the throughput rate at 160 kcps. The overall system performance was tested usinga PIN photodiode-CsI(Tl crystal coupled scintillation detector and gamma standard radioactive sources of Cs-137 andCo-60. Low cost and the compact system size as a result of the implemented logical function are also discussed.

  16. Gamma radiation effects on pequi fruits (Caryocar brasiliense Camb.)

    International Nuclear Information System (INIS)

    Santos, Marcio Ramatiz L.; Arthur, Valter; Salgado, Jocelem M.; Spoto, Marta H. Fillet; Canniatti-Brazaca, Solange G.

    2009-01-01

    The objective of this work was to evaluate the effects of gamma radiation on characteristics of pequi fruits (Caryocar brasiliense Camb.). Just now, they are gained attention of researchers due their nutritional properties, between then is the pequi fruits. Fruits come from Goias State was classified, washed and processed to separate the endocarp (edible part) from pericarp. The endocarps were packing in polyethylene bags with 150 g, labeled and submitted to radiation process (0.0, 0.4, 0.6 and 1.0 kGy doses) on multipurpose irradiator located in IPEN/USP. The samples were analyzed to chemical (pH, trititable acidity, deg Brix, ratio TSS/TTA, lipids, ash, humidity, protein, soluble and insoluble fiber, total carotenoids and antioxidant activity) and physical properties (loss weight, texture and color). The irradiation process using gamma rays from Co 60 was effective to protect pequi fruits in postharvest period. (author)

  17. Slaughterhouse sewage treatment using gamma radiation - economical feasibility study

    International Nuclear Information System (INIS)

    Melo, Rita; Botelho, M. Luisa; Branco, Joaquim

    2005-01-01

    This paper presents preliminary results of a financial viability study for the implementation of gamma radiation technology on a slaughterhouse wastewater treatment industry. Five scenarios were studied, including the current practice, representing different types of treatments and goals, e.g.: water reuse and/or sludge add value as agriculture fertilizers. Cost-benefit analysis, including the net present value (NPV) of each scenario, was used as a technique to compare the relative value of various strategies. Taking in account that the initial investment is amortized after 20 years, the implementation of Co-60 treatment with 20% water reuse and sludge application as agriculture fertilizers represents the most profitable project with the highest NPV. Therefore, the implementation of gamma radiation technology on a slaughterhouse wastewater treatment industry is not only technically viable as well as economically feasible. (author)

  18. Gamma camera

    International Nuclear Information System (INIS)

    Tschunt, E.; Platz, W.; Baer, Ul; Heinz, L.

    1978-01-01

    A gamma camera has a plurality of exchangeable collimators, one of which is replaceably mounted in the ray inlet opening of the camera, while the others are placed on separate supports. Supports are swingably mounted upon a column one above the other

  19. Gamma camera

    International Nuclear Information System (INIS)

    Schlosser, P.A.; Steidley, J.W.

    1980-01-01

    The design of a collimation system for a gamma camera for use in nuclear medicine is described. When used with a 2-dimensional position sensitive radiation detector, the novel system can produce superior images than conventional cameras. The optimal thickness and positions of the collimators are derived mathematically. (U.K.)

  20. External radiation toxicity

    International Nuclear Information System (INIS)

    Fritz, T.E.

    1979-01-01

    The section contains summaries of research on neutron and gamma-ray toxicity in rodents, late effects of low-dose rate, whole-body, protracted exposure to 60 Co gamma rays on young adult beagles, and the effects of protracted, low-dose rate exposure to 60 Co gamma rays on preclinical leukemic phase-related changes in the granulopoietic system of beagles

  1. Scintillation counter, maximum gamma aspect

    International Nuclear Information System (INIS)

    Thumim, A.D.

    1975-01-01

    A scintillation counter, particularly for counting gamma ray photons, includes a massive lead radiation shield surrounding a sample-receiving zone. The shield is disassembleable into a plurality of segments to allow facile installation and removal of a photomultiplier tube assembly, the segments being so constructed as to prevent straight-line access of external radiation through the shield into radiation-responsive areas. Provisions are made for accurately aligning the photomultiplier tube with respect to one or more sample-transmitting bores extending through the shield to the sample receiving zone. A sample elevator, used in transporting samples into the zone, is designed to provide a maximum gamma-receiving aspect to maximize the gamma detecting efficiency. (U.S.)

  2. Gamma radiation influence on Cladonia substellata (lichen) and its effects on limestone rocks

    International Nuclear Information System (INIS)

    Silva, Helena P. de B.; Colaco, Waldeciro; Pereira, Eugenia C.; Silva, Nicacio H. da

    2009-01-01

    The lichens play an important role in decomposition of the rocky substrate, through the chemical weathering of their substances. This work aimed to determine the influence of gamma Ray on usnic acid production of Cladonia substellata and the influence of chelates formation in limestone rocks. Samples with 2.5 g of C. substellata were packed on paper envelopes for irradiation submission to gamma on a Co-60 source. They received 10 different doses: 5, 7, 10, 15, 20, 30, 40, 50, 60 and 80 Gy. Lichen irradiation was conducted on the gamma irradiator (Co-60), and packed over powdered limestone. Lichen samples were analyzed by High Performance Liquid Chromatography (HPLC) and rocky samples by X-Ray Diffractometry. The X-ray diffractogram obtained from the analysis of limestone not subjected to the action of lichen - control sample was compared with limestone subjected to C. substellata irradiated at doses 10, 30 and 80Gy. Increased production of the usnic acid and changes on the rocky samples were noted. We realized that C. substellata increments the usnic acid biosynthesis as the gamma radiation dose is increased, but there is a limit to it. The chelating effect of the usnic acid on limestone was proportional to the produced amount of the substance, which could be extrapolated to natural conditions, where excessive radiation may influence pedogenesis and ecological succession. (author)

  3. Gamma camera

    International Nuclear Information System (INIS)

    Reiss, K.H.; Kotschak, O.; Conrad, B.

    1976-01-01

    A gamma camera with a simplified setup as compared with the state of engineering is described permitting, apart from good localization, also energy discrimination. Behind the usual vacuum image amplifier a multiwire proportional chamber filled with trifluorine bromium methane is connected in series. Localizing of the signals is achieved by a delay line, energy determination by means of a pulse height discriminator. With the aid of drawings and circuit diagrams, the setup and mode of operation are explained. (ORU) [de

  4. Gamma irradiator

    International Nuclear Information System (INIS)

    Simonet, G.

    1986-09-01

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

  5. Gamma teletopography

    International Nuclear Information System (INIS)

    Simonet, G.

    1987-06-01

    The mapping of gamma sources radiation emission in a nuclear plant is an important safety point. A remote gamma ray mapping process was developed in SPS/CEA/SACLAY. It uses the ''pinhole camera'' principle, precursor of photography. It mainly consists of a radiation proof box, with a small orifice, containing sensitive emulsions at the opposite. A first conventional photographic type emulsion photographs the area. A second photographic emulsion shows up the gamma radiations. The superim position of the two shots gives immediate informations of the precise location of each source of radiation in the observed area. To make easier the presentation and to improve the accuracy of the results for radiation levels mapping, the obtained films are digitally processed. The processing assigns a colours scale to the various levels of observed radiations. Taking account physical data and standard parameters, it gets possible to estimate the dose rate. The device is portable. Its compactness and fully independent nature make it suitable for use anywhere. It can be adapted to a remote automatic handling system, robot... so as to avoid all operator exposure when the local dose rate is too high [fr

  6. A modeling of fuzzy logic controller on gamma scanning device

    International Nuclear Information System (INIS)

    Arjoni Amir

    2010-01-01

    Modeling and simulation of controller to set the high position and direction of the source of gamma radiation isotope Co-60 and Nal(TL) detector of gamma scanning device by using fuzzy logic controller FLC have been done. The high positions and in the right direction of gamma radiation and Nal (TI) detector obtained the optimal enumeration. The counting data obtained from gamma scanning device counting system is affected by the instability of high position and direction of the gamma radiation source and Nal(TI) detector or the height and direction are not equal between the gamma radiation source and Nal(TI) detector. Assumed a high position and direction of radiation sources can be fixed while the high position detector h (2, 1,0, -1, -2) can be adjusted up and down and the detector can be changed direction to the left or right angle ω (2, 1 , 0, -1, -2) when the position and direction are no longer aligned with the direction of the source of gamma radiation, the counting results obtained will not be optimal. Movement detector direction towards the left or right and the high detector arranged by the DC motor using fuzzy logic control in order to obtain the amount of output fuzzy logic control which forms the optimal output quantity count. The variation of height difference h between the source position of the gamma radiation detector and change direction with the detector angle ω becomes the input variable membership function (member function) whereas the fuzzy logic for the output variable membership function of fuzzy logic control output is selected scale fuzzy logic is directly proportional to the amount of optimal counting. From the simulation results obtained by the relationship between the amount of data output variable of fuzzy logic controller and the amount of data input variable height h and direction detector ω is depicted in graphical form surface. (author)

  7. Studies on the changes of biologically active complexes of sunflower oil, tard, and butter under gamma irradiation

    International Nuclear Information System (INIS)

    Ivanov, A.; Stamatov, D.

    1976-01-01

    Investigations of changes in the biologically active complex of sunflower oil, lard and butter under the influence of gamma rays: The points examined are the effect of small, medium and large doses (10 4 , 10 6 and 10 7 ) of gamma rays (Co 60 ) and the after-effect on the carotenes, tocopherols, sterols and linoleic acid in sunflower oil, lard and butter. Under these conditions, only the carotenes and tocopherols are subjected to changes to the point of destruction. What was found is a good correlative connection between the changes in the tocopherols and the degree of oxidation of the corresponding fats. (orig.) [de

  8. Quality assurance for gamma knives

    International Nuclear Information System (INIS)

    Jones, E.D.; Banks, W.W.; Fischer, L.E.

    1995-09-01

    This report describes and summarizes the results of a quality assurance (QA) study of the Gamma Knife, a nuclear medical device used for the gamma irradiation of intracranial lesions. Focus was on the physical aspects of QA and did not address issues that are essentially medical, such as patient selection or prescription of dose. A risk-based QA assessment approach was used. Sample programs for quality control and assurance are included. The use of the Gamma Knife was found to conform to existing standards and guidelines concerning radiation safety and quality control of external beam therapies (shielding, safety reviews, radiation surveys, interlock systems, exposure monitoring, good medical physics practices, etc.) and to be compliant with NRC teletherapy regulations. There are, however, current practices for the Gamma Knife not covered by existing, formalized regulations, standards, or guidelines. These practices have been adopted by Gamma Knife users and continue to be developed with further experience. Some of these have appeared in publications or presentations and are slowly finding their way into recommendations of professional organizations

  9. Quality assurance for gamma knives

    Energy Technology Data Exchange (ETDEWEB)

    Jones, E.D.; Banks, W.W.; Fischer, L.E. [Lawrence Livermore National Lab., CA (United States)

    1995-09-01

    This report describes and summarizes the results of a quality assurance (QA) study of the Gamma Knife, a nuclear medical device used for the gamma irradiation of intracranial lesions. Focus was on the physical aspects of QA and did not address issues that are essentially medical, such as patient selection or prescription of dose. A risk-based QA assessment approach was used. Sample programs for quality control and assurance are included. The use of the Gamma Knife was found to conform to existing standards and guidelines concerning radiation safety and quality control of external beam therapies (shielding, safety reviews, radiation surveys, interlock systems, exposure monitoring, good medical physics practices, etc.) and to be compliant with NRC teletherapy regulations. There are, however, current practices for the Gamma Knife not covered by existing, formalized regulations, standards, or guidelines. These practices have been adopted by Gamma Knife users and continue to be developed with further experience. Some of these have appeared in publications or presentations and are slowly finding their way into recommendations of professional organizations.

  10. Luminescence from {gamma}-irradiated humic acid

    Energy Technology Data Exchange (ETDEWEB)

    Goraczko, Wieslaw [Faculty of Chemical Technology, Radio- and Photochemistry Department, Poznan University of Technology, ul. Piotrowo 3, 60-965 Poznan (Poland); Slawinski, Janusz [Institute of Ecotechnology, State Higher Vocational School, ul. Ks. Kard. S.Wyszynskiego 38, 62-200 Gniezno (Poland)

    2008-07-15

    This study was conducted to investigate the ultraweak delayed radiochemiluminescence (RCL) spectra, kinetics and spectroscopic properties of humic acids (HAs) after {gamma}-radiation exposure (absorbed doses of 1-10 kGy, Co-60) in model systems. The kinetics and spectral distribution of RCL (340-650 nm) were measured using the single photon counting (SPC) method and cut-off filters. The intensity of fluorescence ({lambda}{sub ex}=390, 440, 490 and 540 nm) covering the spectral range 400-580 nm was heavily dependent on the {lambda}{sub ex} and slightly increased with the absorbed dose of {gamma}-radiation. Absorption spectra (the range 240-800 nm) and color coefficients E{sub 2.6/4} and E{sub 4/6} of irradiated solutions indicated that post-radiative degradation/polymerization processes take place in the HA, changing their macromolecule size or properties. Comparison of FTIR spectra and elemental analysis proved an increased O and decreased C atoms in irradiated samples. The data indicate on the radiolysis-induced degradation of native HA into fulvic-like acids with higher hydrophilicity and lower molecular size.

  11. Kraft cooking of gamma irradiated wood, (1)

    International Nuclear Information System (INIS)

    Inaba, Masamitsu; Meshitsuka, Gyosuke; Nakano, Junzo

    1979-01-01

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

  12. Structure and content of the galaxy and galactic gamma rays

    Energy Technology Data Exchange (ETDEWEB)

    1976-01-01

    The conference included papers on ..gamma..-ray pulsars, galactic diffuse flux and surveys, radio surveys of external galaxies, galactic distribution of pulsars, and galactic gamma emission. Galactic structure drawing on all branches of galactic astronomy is discussed. New and unpublished material is included. (JFP)

  13. Gamma teletopography

    International Nuclear Information System (INIS)

    Simonet, G.

    1986-09-01

    To set the gamma activity cartography is an important element of safety in numerous cases: intervention in hot cell, search of a radioactive source, examination of radioactive waste circuit followed by a reprocessing definition of decontamination and decommissioning processes and for all other accidents. The device presented here is like a ''black box'' with an aperture and an emulsion photosensitive to the opposite; a classical film takes photography of the place; a X-ray type emulsion gives a spot more or less contrasted and extensive corresponding to each source. Images can be processed with a microprocessor [fr

  14. Regulating multiple externalities

    DEFF Research Database (Denmark)

    Waldo, Staffan; Jensen, Frank; Nielsen, Max

    2016-01-01

    Open access is a well-known externality problem in fisheries causing excess capacity and overfishing. Due to global warming, externality problems from CO2 emissions have gained increased interest. With two externality problems, a first-best optimum can be achieved by using two regulatory instrume......Open access is a well-known externality problem in fisheries causing excess capacity and overfishing. Due to global warming, externality problems from CO2 emissions have gained increased interest. With two externality problems, a first-best optimum can be achieved by using two regulatory...

  15. Gamma knife

    International Nuclear Information System (INIS)

    Kawamoto, Shunsuke; Takakura, Kintomo

    1991-01-01

    As to the gamma knife which is the radiation surgery device developed in Sweden a quarter century ago, its principle, structure, treatment techniques, already established clinical effect and the problems being left for hereafter are described. This treatment means supplements the operation under microscopes, and at present it takes the important position in neurosurgery, but hereafter, by the interdisciplinary cooperation of neurosurgery and clinical radiobiology, the more development can be expected. The method of irradiating the radiation of high dose selectively to a target region and breaking its tissue is called radiosurgery, and the device developed for this purpose is the gamma knife. First, it was applied to functional diseases, but good results were obtained by its application to auditory nerve and brain blood vessels, and it establishes the position as the safe treatment method of the morbid state in the deep part of brains, which is difficult to reach by operation. Accompanying the recent progress of the operation of skull base part, attention is paid to its application to various tumors in skull base. On the other hand, the radiosurgery combining a cyclotron or a linear accelerator with stereotaxic brain surgery is actively tried mainly to the deformation of brain blood vessels. (K.I.)

  16. ExternE National Implementation Finland

    Energy Technology Data Exchange (ETDEWEB)

    Pingoud, K; Maelkki, H; Wihersaari, M; Pirilae, P [VTT Energy, Espoo (Finland); Hongisto, M [Imatran Voima Oy, Vantaa (Finland); Siitonen, S [Ekono Energy Ltd, Espoo (Finland); Johansson, M [Finnish Environment Institute, Helsinki (Finland)

    1999-07-01

    ExternE National Implementation is a continuation of the ExternE Project, funded in part by the European Commission's Joule III Programme. This study is the result of the ExternE National Implementation Project for Finland. Three fuel cycles were selected for the Finnish study: coal, peat and wood-derived biomass, which together are responsible for about 40% of total electricity generation in Finland and about 75% of the non-nuclear fuel based generation. The estimated external costs or damages were dominated by the global warming (GW) impacts in the coal and peat fuel cycles, but knowledge of the true GW impacts is still uncertain. From among other impacts that were valued in monetary terms the human health damages due to airborne emissions dominated in all the three fuel cycles. Monetary valuation for ecosystem impacts is not possible using the ExternE methodology at present. The Meri-Pori power station representing the coal fuel cycle is one of the world's cleanest and most efficient coal-fired power plants with a condensing turbine. The coal is imported mainly from Poland. The estimated health damages were about 4 mECU/kWh, crop damages an order of magnitude lower and damages caused to building materials two orders of magnitude lower. The power stations of the peat and biomass fuel cycles are of CHP type, generating electricity and heat for the district heating systems of two cities. Their fuels are of domestic origin. The estimated health damages allocated to electricity generation were about 5 and 6 mECU/kWh, respectively. The estimates were case-specific and thus an generalisation of the results to the whole electricity generation in Finland is unrealistic. Despite the uncertainties and limitations of the methodology, it is a promising tool in the comparison of similar kinds of fuel cycles, new power plants and pollution abatement technologies and different plant locations with each other. (orig.)

  17. ExternE National Implementation Finland

    International Nuclear Information System (INIS)

    Pingoud, K.; Maelkki, H.; Wihersaari, M.; Pirilae, P.; Hongisto, M.; Siitonen, S.; Johansson, M.

    1999-01-01

    ExternE National Implementation is a continuation of the ExternE Project, funded in part by the European Commission's Joule III Programme. This study is the result of the ExternE National Implementation Project for Finland. Three fuel cycles were selected for the Finnish study: coal, peat and wood-derived biomass, which together are responsible for about 40% of total electricity generation in Finland and about 75% of the non-nuclear fuel based generation. The estimated external costs or damages were dominated by the global warming (GW) impacts in the coal and peat fuel cycles, but knowledge of the true GW impacts is still uncertain. From among other impacts that were valued in monetary terms the human health damages due to airborne emissions dominated in all the three fuel cycles. Monetary valuation for ecosystem impacts is not possible using the ExternE methodology at present. The Meri-Pori power station representing the coal fuel cycle is one of the world's cleanest and most efficient coal-fired power plants with a condensing turbine. The coal is imported mainly from Poland. The estimated health damages were about 4 mECU/kWh, crop damages an order of magnitude lower and damages caused to building materials two orders of magnitude lower. The power stations of the peat and biomass fuel cycles are of CHP type, generating electricity and heat for the district heating systems of two cities. Their fuels are of domestic origin. The estimated health damages allocated to electricity generation were about 5 and 6 mECU/kWh, respectively. The estimates were case-specific and thus an generalisation of the results to the whole electricity generation in Finland is unrealistic. Despite the uncertainties and limitations of the methodology, it is a promising tool in the comparison of similar kinds of fuel cycles, new power plants and pollution abatement technologies and different plant locations with each other. (orig.)

  18. ExternE National Implementation Finland

    Energy Technology Data Exchange (ETDEWEB)

    Pingoud, K.; Maelkki, H.; Wihersaari, M.; Pirilae, P. [VTT Energy, Espoo (Finland); Hongisto, M. [Imatran Voima Oy, Vantaa (Finland); Siitonen, S. [Ekono Energy Ltd, Espoo (Finland); Johansson, M. [Finnish Environment Institute, Helsinki (Finland)

    1999-07-01

    ExternE National Implementation is a continuation of the ExternE Project, funded in part by the European Commission's Joule III Programme. This study is the result of the ExternE National Implementation Project for Finland. Three fuel cycles were selected for the Finnish study: coal, peat and wood-derived biomass, which together are responsible for about 40% of total electricity generation in Finland and about 75% of the non-nuclear fuel based generation. The estimated external costs or damages were dominated by the global warming (GW) impacts in the coal and peat fuel cycles, but knowledge of the true GW impacts is still uncertain. From among other impacts that were valued in monetary terms the human health damages due to airborne emissions dominated in all the three fuel cycles. Monetary valuation for ecosystem impacts is not possible using the ExternE methodology at present. The Meri-Pori power station representing the coal fuel cycle is one of the world's cleanest and most efficient coal-fired power plants with a condensing turbine. The coal is imported mainly from Poland. The estimated health damages were about 4 mECU/kWh, crop damages an order of magnitude lower and damages caused to building materials two orders of magnitude lower. The power stations of the peat and biomass fuel cycles are of CHP type, generating electricity and heat for the district heating systems of two cities. Their fuels are of domestic origin. The estimated health damages allocated to electricity generation were about 5 and 6 mECU/kWh, respectively. The estimates were case-specific and thus an generalisation of the results to the whole electricity generation in Finland is unrealistic. Despite the uncertainties and limitations of the methodology, it is a promising tool in the comparison of similar kinds of fuel cycles, new power plants and pollution abatement technologies and different plant locations with each other. (orig.)

  19. Delignification of Sawdust White Teak (Gmelina arborea Roxb. by Fungi Phanerochaete chrysosporium Irradiated Gamma Ray

    Directory of Open Access Journals (Sweden)

    Nurhasni Nurhasni

    2016-12-01

    Full Text Available Abstrak Biomassa lignoselulosa yang merupakan limbah pemanenan kayu harus dilakukan proses untuk memisahkan selulosa, hemiselulosa dan lignin sehingga dapat termanfaatkan. Penelitian ini bertujuan untuk mengetahui efektivitas inokulan fungi Phanerochaete chrysosporium iradiasi gamma dan pretreatment kimia terhadap percepatan delignifikasi serbuk kayu jati putih (Gmelina arborea Roxb. sehingga dapat dimanfaatkan dalam proses pulping. Pada penelitian ini dilakukan pretreatment substrat kayu jati putih (Gmelina arborea Roxb. menggunakan larutan NaOH 1% dan H2SO4 1% serta iradiasi gamma Co-60, yang mempunyai daya ionisasi kecil, daya tembus yang tinggi serta Co-60 dapat memancarkan sinar gamma dengan waktu paruh pendek. Penelitian ini dilakukan dalam dua tahap, tahap pertama penentuan dosis optimum iradiasi gamma terhadap fungi Phanerochaete chrysosporium (0 Gy, 200 Gy, 400 Gy, 600 Gy, 800 Gy, dan 1000 Gy dan tahap kedua analisis karakteristik substrat kayu jati putih yang telah di pretreatment dengan metode Solid State Fermentation (SSF selama 21 hari. Hasil penelitian menunjukkan bahwa dosis optimum pemberian iradiasi gamma pada fungi Phanerochaete chrysosporium yaitu pada dosis 600 Gy yang dapat meningkatkan aktivitas enzim lignin peroksidase (LiP sebesar 22.18 U/mL. Proses pretreatment kimia dengan menggunakan H2SO4 1% dapat mempercepat proses biodelignifikasi yang menghasilkan efisiensi degradasi lignin tertinggi yaitu sebesar 25.65%.   Kata kunci: Lignoselulosa, delignifikasi, Solid State Fermentation (SSF, Phanerochaete chrysosporium,iradiasi gamma.   Abstract   Lignocellulose biomass is waste wood harvesting should be a process for separating cellulose, hemicellulose and lignin that can be utilized. This study aims to determine the effectiveness of the inoculant fungi Phanerochaete chrysosphorium gamma irradiation and chemical pretreatment to accelerate delignification powder white teak (Gmelina arborea Roxb.. In this research

  20. Electrical characterization of commercial NPN bipolar junction transistors under neutron and gamma irradiation

    Directory of Open Access Journals (Sweden)

    OO Myo Min

    2014-01-01

    Full Text Available Electronics components such as bipolar junction transistors, diodes, etc. which are used in deep space mission are required to be tolerant to extensive exposure to energetic neutrons and ionizing radiation. This paper examines neutron radiation with pneumatic transfer system of TRIGA Mark-II reactor at the Malaysian Nuclear Agency. The effects of the gamma radiation from Co-60 on silicon NPN bipolar junction transistors is also be examined. Analyses on irradiated transistors were performed in terms of the electrical characteristics such as current gain, collector current and base current. Experimental results showed that the current gain on the devices degraded significantly after neutron and gamma radiations. Neutron radiation can cause displacement damage in the bulk layer of the transistor structure and gamma radiation can induce ionizing damage in the oxide layer of emitter-base depletion layer. The current gain degradation is believed to be governed by the increasing recombination current in the base-emitter depletion region.

  1. External Otitis (Swimmer's Ear)

    Science.gov (United States)

    ... otitis. Fungal external otitis (otomycosis), typically caused by Aspergillus niger or Candida albicans, is less common. Boils are ... in the ear. Fungal external otitis caused by Aspergillus niger usually causes grayish black or yellow dots (called ...

  2. ExternE: Externalities of energy Vol. 2. Methodology

    International Nuclear Information System (INIS)

    Berry, J.; Holland, M.; Watkiss, P.

    1995-01-01

    This report describes the methodology used by the ExternE Project of the European Commission (DGXII) JOULE Programme for assessment of the external costs of energy. It is one of a series of reports describing analysis of nuclear, fossil and renewable fuel cycles for assessment of the externalities associated with electricity generation. Part I of the report deals with analysis of impacts, and Part II with the economic valuation of those impacts. Analysis is conducted on a marginal basis, to allow the effect of an incremental investment in a given technology to be quantified. Attention has been paid to the specificity of results with respect to the location of fuel cycle activities, the precise technologies used, and the type and source of fuel. The main advantages of this detailed approach are as follows: It takes full and proper account of the variability of impacts that might result from different power projects; It is more transparent than analysis based on hypothetically 'representative' cases for each of the different fuel cycles; It provides a framework for consistent comparison between fuel cycles. A wide variety of impacts have been considered. These include the effects of air pollution on the natural and human environment, consequences of accidents in the workplace, impacts of noise and visual intrusion on amenity, and the effects of climate change arising from the release of greenhouse gases. Wherever possible we have used the 'impact pathway' or 'damage function' approach to follow the analysis from identification of burdens (e.g. emissions) through to impact assessment and then valuation in monetary terms. This has required a detailed knowledge of the technologies involved, pollutant dispersion, analysis of effects on human and environmental health, and economics. In view of this the project brought together a multi-disciplinary team with experts from many European countries and the USA. The spatial and temporal ranges considered in the analysis are

  3. ASH External Web Portal (External Portal) -

    Data.gov (United States)

    Department of Transportation — The ASH External Web Portal is a web-based portal that provides single sign-on functionality, making the web portal a single location from which to be authenticated...

  4. Gamma camera

    International Nuclear Information System (INIS)

    Tschunt, E.; Platz, W.; Baer, U.; Heinz, L.

    1978-01-01

    A gamma camera has a plurality of exchangeable collimators, one of which is mounted in the ray inlet opening of the camera, while the others are placed on separate supports. The supports are swingably mounted upon a column one above the other through about 90 0 to a collimator exchange position. Each of the separate supports is swingable to a vertically aligned position, with limiting of the swinging movement and positioning of the support at the desired exchange position. The collimators are carried on the supports by means of a series of vertically disposed coil springs. Projections on the camera are movable from above into grooves of the collimator at the exchange position, whereupon the collimator is turned so that it is securely prevented from falling out of the camera head

  5. Kajian Pengaruh Radiasi Sinar Gamma Terhadap Susut Bobot Pada Buah Jambu Biji Merah Selama Masa Penyimpanan

    Directory of Open Access Journals (Sweden)

    M. Akrom

    2014-01-01

    Full Text Available Telah dilakukan radiasi pada sampel jambu biji merah (psidium guajava linn pada variasi dosis 0.2, 0.4, 0.6, 0.8, dan 1 kGy menggunakan sinar gamma dengan sumber isotop Co-60 serta sampel yang tidak diradiasi sebagai sampel kontrol. Penelitian ini bertujuan untuk mengetahui pengaruh radiasi sinar gamma terhadap susut bobot sebagai indikasi dari terjadinya perlambatan proses fisiologis pada buah jambu biji merah selama masa penyimpanan. Sampel jambu biji merah diradiasi sesuai dosis yang ditentukan kemudian disimpan dalam wadah plastik selama 8 hari masa penyimpanan. Hari ke 4 dan ke 8 dilakukan evaluasi terhadap massa sampel untuk mengetahui penyusutan bobot yang terjadi. Hasilnya menunjukkan bahwa sampel yang tidak diradiasi mengalami penyusutan bobot rata-rata 20.27% dan sampel yang diradiasi mengalami penyusutan bobot rata-rata sebesar 1.23 – 5.98%. Perlakuan radiasi gamma mampu memperlambat proses fisiologis dimana terjadi perlambatan penyusutan bobot pada buah jambu biji merah selama masa penyimpanan. The samples of red guava (psidium guajava linn have been irradiated at variation doses of 0.2, 0.4, 0.6, 0.8, and 1 kGy using gamma rays with Co-60 isotope source and un-irradiated samples as control. The purpose of this research was to determine the effect of gamma irradiation on shrinkage weights as indication of slowing in physiological processes on red guava fruit during storage. Red guava fruit samples were irradiated in certain doses then saved in plastic pan during 8 days storage time. The fourth and eighth day sample mass was measured to determine the shrinkage of the weight. The result showed that un-irradiated sample was shrinkage weighted average 20.27% and the samples were irradiated shrinkage weight by an average of 1.23 to 5.98%. Gamma irradiation is able to slow the physiological processes which cause shrinkage weight on red guava fruit during storage.

  6. The induction mutation effects of "6"0Co gamma radiation on physiological growth of tomato

    International Nuclear Information System (INIS)

    Gusti Ngurah Sutapa; I Gde Antha Kasmawan

    2016-01-01

    Almost all types of cuisine in Indonesia are using tomatoes as the base material of manufacture. The nutritional value contained in tomatoes is also quite high, because there is a number of vitamin content required by the human body. In addition, the tomatoes in plants featured national horticultural commodity and priority on a number of provinces in Indonesia. So many benefits of tomatoes indicates that the productivity of tomatoes should be improved. One improvement in terms of quality can be done by means of mutation induction with gamma radiation of Co-60. Induction of mutations are genetic changes caused by human effort, one of them is by using radioactive materials. Gamma rays of Co-60 from the IRPASENA facility was exposed to tomato seeds at doses of 50, 100, 150, 200 and 250 Gy. And then measurements were conducted on the physiological growth of leaf width, plant height, number of fruit and wet weight of tomatoes from week 1 until harvest. The results showed a growth curve of tomato is in accordance with sigmoidal plant physiological growth curve. Optimal physiological growth of tomato plants was obtained at dose of gamma radiation of 100 Gy. At this optimal dose physiological growth of tomato plants is the best (superior) than in doses below and above 100 Gy and control. (author)

  7. Efficiency factor of a chemical nuclear reactor with gamma sources

    International Nuclear Information System (INIS)

    Anguis T, C.

    1975-01-01

    A chemonuclear reactor is simulated in order to calculate the efficiency factor of molecular species in chemical reactions induced by gamma radiation, with the purpose to obtain information for its design and consider the electromagnetic energy as a possible solution to the present problem of energy. The research is based on a mathematical model of succesive Compton processes applied to spherical and cylindrical geometry and corroborated through the absorbed dose and the experimental date of the increase factor, for the radioisotopic sources Co-60 and Cs-137 relating the quantity of energy deposited into various cylinders with the G value, the relation radius/height of the reactor is optimized according to the molecular production. This is illustrated with the radiolysis of a solution of CH 3 OH/H 2 O which forms H 2 and with the obtainment of C 2 H 5 Br that represents and industrial process induced radioactively. The results show a greater energy deposition with Cs-137 but a larger production of H 2 /hr with Co-60, and besides we can find high production values of C 2 H 5 Br. The cylinder with more advantages is that whose relation R/H is of 0.5. It can be concluded that the final selection of the reactor should be made after a more intense study of the used isotope and the source activity. The efficiency factor of H 2 can be increased selecting the appropriate type and concentration of solute of the irradiated aqueous solutions

  8. Gamma-ray effect on sweet potato

    International Nuclear Information System (INIS)

    Ferdes, O.; Ciofu, R.; Stroia, L.; Ghering, A.; Ferdes, M.

    1994-01-01

    The paper presents the results on modification occurred in biochemical properties of sweet potato (Ipomea batatus L.) after gamma irradiation. Two varieties, named Victoria Ianb (a white variety) and Portocaliu (a red variety), were selected and acclimatized for the agrometeorological conditions of Romania. The samples consist of roots from both usual and experimental crops. They were irradiated in batch, one week after harvesting, with a ICPR Co-60 gamma-ray source by approx. 370 TBq, dose range 100-500 Gy, dose rate 100±5 Gy/hour, dose uniformity ±5%, temperature 10 o C, 80±5% relative humidity (rh). The irradiation doses received were checked using the Fricke ferrous sulphate dosimeter procedure. The roots were kept two months at relative darkness, 6-11 o C, 60-75% rh and analyzed from time to time (initial, 5, 7, 14, 30 and 60 days). The following parameters are analyzed by conventional methods: total and reducing sugars (in De equivalent, %, on dry weight basis), starch content and the activities of sugar metabolizing enzymes. The red variety had a better behaviour towards irradiation that the white one. The sugar contents (both total and reducing), as well as starch, varied more in the white variety. The sugar metabolizing enzyme activities were influenced by both irradiation and storage conditions. Their activities were maximal at 200 and 300 Gy, and decreased significantly at higher doses. The activities also decreased in time, their variations being higher at lower doses (100 and 200 Gy). The results showed no significant influence of gamma irradiation on storage life. The modifications induced in sugar contents and enzyme activities had maximal effects at 200-300 Gy. (author)

  9. Storage behavior of an early garlic (Allium sativum L.) subject to gamma-ray radioinhibition

    International Nuclear Information System (INIS)

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

    1990-01-01

    Garlic bulbs of an early cultivar (Rosado Paraguayo) were irradiated with a dose of 50 Gy of Co-60 gamma rays at 30 days after harvest. Experimental lots were stored up to 300 days in a commercial warehouse (6-32 degrees C; R.H. 40-50%). The treatment reduced the weight loss of the bulbs and increased the percentage of both marketable bulbs and cloves without affecting organoleptic properties. The results show that both the raw/fresh market for this early cultivar and the garlic processing industry would profit from the radioinhibition process

  10. Conditioning the gamma spectrometer for activity measurement at very high background

    OpenAIRE

    Yan, Weihua; Zhang, Liguo; Zhang, Zhao; Xiao, Zhigang

    2013-01-01

    The application of a high purity germanium (HPGe) gamma spectrometer in determining the fuel element burnup in a future reactor is studied. The HPGe detector is exposed by a Co60 source with varying irradiation rate from 10 kcps to 150 kcps to simulate the input counting rate in real reactor environment. A Cs137 and a Eu152 source are positioned at given distances to generate certain event rate in the detector with the former being proposed as a labeling nuclide to measure the burnup of fuel ...

  11. Gamma-irradiation induced mutagenesis on some microbial strains of interest in food biotechnologies

    International Nuclear Information System (INIS)

    Ferdes, O.S.; Ferdes, M.; Dumitru, E.; Mencinicopschi, G.

    1993-01-01

    In this paper there were presented the results concerning gamma-ray effects on some microbial strains which are of interest in food biotechnologies. The irradiations are performed to a Co-60 source, under several condition, at dose rates between 0.1-2.0 kGy/h and in a dose range between 0.1-20.0 kGy. The microbial strains are of Bacillus subtilis, Aspergillus niger, Mucor pusillus and Monascus rubens from IFC collection. There were established the survival curves and the optimum irradiation doses for mutagenic effects. There were isolated, analysed and characterised some mutant strains, with better properties in obtaining food enzymes and pigments. (orig.)

  12. A biotechnological project with a gamma radiation source of 100,000 Ci

    International Nuclear Information System (INIS)

    Lombardo, J.H.; Smolko, E.E.

    1990-01-01

    A project for the production of radiovaccines and other bio-medical products is presented which includes a radiation facility provided with a gamma ray source equivalent to 100,000 Ci of Co-60. The whole process incorporates novel basic features in virus production and inactivation steps. The former is carried out in animals previously subjected to immunodepression through electromagnetic radiation. The latter is obtained at low temperatures by using either electromagnetic or particle radiations. A vaccine manufacture process is shown to illustrate the utilization of ionizing radiations to obtain a foot and mouth disease virus (FMDV) vaccine with good antigenic quality and low cost. (author)

  13. In vitro study of dose rate effect on Leksell Gamma Knife Perfexion

    International Nuclear Information System (INIS)

    Pastykova, V.; Novotny, J. jr.; Vachelova, J.; Davidkova, M.; Liscak, R.

    2018-01-01

    The main purpose of the study is to evaluate the radiobiological effect of the dose rate changes in Leksell Gamma Knife (LGK) clinical conditions. In principle there are two reasons why dose rate on LGK is reduced during patient irradiation: 1) Co-60 sources decay with a half-life of 5.26 years and 2) using multiple iso-centers and conformal treatment plans (e.g. with blocked beams). This pilot study is an experimental work performed in vitro with medulloblastoma DAOY cells. Are there effects caused by low dose rate which could negatively influence the clinical outcome of the radiosurgery? (authors)

  14. X-Ray-Driven Gamma Emission

    International Nuclear Information System (INIS)

    Carroll, J. J.; Karamian, S. A.; Rivlin, L. A.; Zadernovsky, A. A.

    2001-01-01

    X-ray-driven gamma emission describes processes that may release nuclear energy in a 'clean' way, as bursts of incoherent or coherent gamma rays without the production of radioactive by-products. Over the past decade, studies in this area, as a part of the larger field of quantum nucleonics, have gained tremendous momentum. Since 1987 it has been established that photons could trigger gamma emission from a long-lived metastable nuclear excited state of one nuclide and it appears likely that triggering in other isotopes will be demonstrated conclusively in the near future. With these experimental results have come new proposals for the creation of collective and avalanche-like incoherent gamma-ray bursts and even for the ultimate light source, a gamma-ray laser. Obviously, many applications would benefit from controlled bursts of gamma radiation, whether coherent or not. This paper reviews the experimental results and concepts for the production of gamma rays, driven by externally produced X-rays

  15. Gamma camera

    International Nuclear Information System (INIS)

    Conrad, B.; Heinzelmann, K.G.

    1975-01-01

    A gamma camera is described which obviates the distortion of locating signals generally caused by the varied light conductive capacities of the light conductors in that the flow of light through each light conductor may be varied by means of a shutter. A balancing of the flow of light through each of the individual light conductors, in effect, collective light conductors may be balanced on the basis of their light conductive capacities or properties, so as to preclude a distortion of the locating signals caused by the varied light conductive properties of the light conductors. Each light conductor has associated therewith two, relative to each other, independently adjustable shutters, of which one forms a closure member and the other an adjusting shutter. In this embodiment of the invention it is thus possible to block all of the light conductors leading to a photoelectric transducer, with the exception of those light conductors which are to be balanced. The balancing of the individual light conductors may then be obtained on the basis of the output signals of the photoelectric transducer. (auth)

  16. Gamma ray generator

    Science.gov (United States)

    Firestone, Richard B; Reijonen, Jani

    2014-05-27

    An embodiment of a gamma ray generator includes a neutron generator and a moderator. The moderator is coupled to the neutron generator. The moderator includes a neutron capture material. In operation, the neutron generator produces neutrons and the neutron capture material captures at least some of the neutrons to produces gamma rays. An application of the gamma ray generator is as a source of gamma rays for calibration of gamma ray detectors.

  17. ExternE: Externalities of energy Vol. 1. Summary

    International Nuclear Information System (INIS)

    Holland, M.; Berry, J.

    1995-01-01

    There is a growing requirement for policy analysts to take account of the environment in their decision making and to undertake the specified cost-benefit analysis. Within the European Union this is reflected in the 5th Environmental Action Programme, and the Commission's White Paper entitled 'Growth, competitiveness, employment and the ways forward to the 21st century'. This has led to a need for evaluation of environmental externalities. The ExternE Project commenced in 1991 as the European part of a collaborative study between the European Commission and the US Department of Energy. It aims to be the first systematic approach to the evaluation of external costs of a wide range of different fuel cycles. The project will result in an operational accounting framework for the quantification and monetarisation of priority environmental and other externalities. This framework will allow the calculation of the marginal external costs and benefits for specific power plants, at specific sites using specified technologies. There are three major phases in the project. Phase 1 was undertaken in collaboration with the US Department of Energy. In this phase the teams jointly developed the conceptual approach and methodology and shared scientific information for application to a number of fuel cycles. On the European side work concentrated on the nuclear and coal fuel cycles which together were expected to raise many of the fundamental issues in fuel cycle analysis. The project is currently nearing completion of Phase 2. During this phase the methodology has been applied to a wide range of different fossil, nuclear and renewable fuel cycles for power generation and energy conservation options. Also a series of National Implementation Programmes is underway in which the methodology and accounting framework are being applied to reference sites throughout Europe. In addition the general methodology is being extended to address the evaluation of externalities associated with

  18. Externalities of fuel cycles 'ExternE' project. Summary report

    International Nuclear Information System (INIS)

    Holland, M.; Berry, J.

    1994-01-01

    There is a growing requirement for policy analysts to take account of the environment in their decision making and to undertake the specified cost-benefit analysis. Within the European Union this is reflected in the 5th Environmental Action Programme, and the Commission's White Paper entitled 'Growth, competitiveness, employment and the ways forward to the 21st century'. This has led to a need for evaluation of environmental externalities. The ExternE Project commenced in 1991 as the European part of a collaborative study between the European Commission and the US Department of Energy. It aims to be the first systematic approach to the evaluation of external costs of a wide range of different fuel cycles. The project will result in an operational accounting framework for the quantification and monetarisation of priority environmental and other externalities. This framework will allow the calculation of the marginal external costs and benefits for specific power plants, at specific sites using specified technologies. There are three major phases in the project. Phase I was undertaken in collaboration with the US Department of Energy. In this phase the teams jointly developed the conceptual approach and methodology and shared scientific information for application to a number of fuel cycles. On the European side work concentrated on the nuclear and coal fuel cycles which together were expected to raise many of the fundamental issues in fuel cycle analysis. The project is currently nearing completion of Phase 2. During this phase the methodology has been applied to a wide range of different fossil, nuclear and renewable fuel cycles for power generation and energy conservation options. Also a series of National Implementation Programmes are underway in which the methodology and accounting framework are being applied to reference sites throughout Europe. In addition the general methodology is being extended to address the evaluation of externalities associated with

  19. Design of device for testing in the gamma irradiator

    International Nuclear Information System (INIS)

    Mariano H, E.

    1991-02-01

    In eves of the recharge of the Gamma Irradiator, JS-6500 it was detected, that there was contamination in the container that housed the pencils of Co-60, coming from Argentina, country to which the ININ buys it recharges. It was determined that the contamination in the container was it interns and after discussing several solution options it was determined to manufacture a device to make a washing of the pencils. It was touch to the Management of Radiological Safety to determine the conceptual design of the device to make the washing and the way of operation of the same one. The Management of Prototypes and Models was responsibility of the mechanical design and its production. (Author)

  20. Synthesis of copper polyacrylate nanocomposites by gamma irradiation

    International Nuclear Information System (INIS)

    Casalme, Loida Olores

    2005-04-01

    This research involves the synthesis of copper nanoparticles with controlled size by the application of gamma radiation with varying polyacrylic acid (PAA) and CuSO 4 concentration. An alternative and convenient method was done which employs Co 60 irradiation of solutions of copper salt and PAA with irradiation dose of 1.6, 3.6, 6.4, and 9.2 MRad. The effect of polymer and copper sulfate's initial concentrations as well as the effect of the presence of alcohol as radical scavenger and the presence of ethylenediaminetetraacetic acid as stabilizer were evaluated. Characterization of nanocomposite properties such as plasmon resonance band, fluorescence, and particle morphology and size were determined. Layer-by-layer assembly of Cu-PAA nanocomposites and polydiallyl dimethyl ammonium chloride (PDDA) was also constructed. Stability of the synthesized copper-PAA nanocomposites in terms of the disappearance of plasmon band with time was evaluated. (Author)

  1. A simple and efficient gamma irradiator for RVNRL

    Energy Technology Data Exchange (ETDEWEB)

    Smolko, E; Ferenaz, G; Docters, E [Comision Nacional de Energia Atomica, Buenos Aires (Argentina); Makuuchi, Keizo [Japan Atomic Energy Research Inst., Takasaki, Gunma (Japan). Takasaki Radiation Chemistry Research Establishment

    1997-12-31

    This work describes a new design of a gamma irradiator for RVNRL which obeys a reliable operation and an efficient economical equation. Our irradiator is of a nobel design according to present requirements of latex industries and to the state of the art of radiation technology. The irradiator is of a wet storage type, where the radioactive sources are fixed in the reactor vessel, permanently submerged in deionized water. Preformulated latex is pumped from a deposited vessel into the reactor vessel and it is recirculated during the irradiation cycle avoiding turbulences and dose inhomogeneities. The irradiation time per one ton batch with a Co-60 charge of 3.5E15 Bq (100 kCi) is of approximately 4 hours

  2. Disinfestation of whole and ground spices by gamma-irradiation

    International Nuclear Information System (INIS)

    Padwal-Desai, S.R.; Sharma, Arun; Amonkar, S.V.

    1987-01-01

    Number of insect species were identified in chilli (Capsicum annum Linn), turmeric (Curcuma longa Linn), ginger (Zingiber officinale Roscoe), pepper (Piper nigrum Linn) and coriander (Coriandrum sativum) and also in two commercial brands of prepacked ground spices. Lasioderma serricorne (Cigarette beetle), Oryzaephilus surinamensis (Saw toothed grain beetle), Rhizopertha dominica (Lesser grain borer), Sitotroga cerealella (Angoumois grain moth) and Tribolium castaneum (Red flour beetle) were the predominant pest species found in these spices. Exposure of spices to Co 60 gamma irradiation at 1 kGy dose level did not show adult emergence of insects in these species during storage at ambient temperature (28-30degC) indicating that the radiation dose (10 kGy) that has been shown to be effective for microbial decontamination of spices destroys insect pests as well. (author). 8 refs

  3. A simple and efficient gamma irradiator for RVNRL

    International Nuclear Information System (INIS)

    Smolko, E.; Ferenaz, G.; Docters, E.; Keizo Makuuchi

    1996-01-01

    This work describes a new design of a gamma irradiator for RVNRL which obeys a reliable operation and an efficient economical equation. Our irradiator is of a nobel design according to present requirements of latex industries and to the state of the art of radiation technology. The irradiator is of a wet storage type, where the radioactive sources are fixed in the reactor vessel, permanently submerged in deionized water. Preformulated latex is pumped from a deposited vessel into the reactor vessel and it is recirculated during the irradiation cycle avoiding turbulences and dose inhomogeneities. The irradiation time per one ton batch with a Co-60 charge of 3.5E15 Bq (100 kCi) is of approximately 4 hours

  4. Performance evaluation of a rectifier column using gamma column scanning

    Directory of Open Access Journals (Sweden)

    Aquino Denis D.

    2017-12-01

    Full Text Available Rectifier columns are considered to be a critical component in petroleum refineries and petrochemical processing installations as they are able to affect the overall performance of these facilities. It is deemed necessary to monitor the operational conditions of such vessels to optimize processes and prevent anomalies which could pose undesired consequences on product quality that might lead to huge financial losses. A rectifier column was subjected to gamma scanning using a 10-mCi Co-60 source and a 2-inch-long detector in tandem. Several scans were performed to gather information on the operating conditions of the column under different sets of operating parameters. The scan profiles revealed unexpected decreases in the radiation intensity at vapour levels between trays 2 and 3, and between trays 4 and 5. Flooding also occurred during several scans which could be attributed to parametric settings.

  5. Decomposition of water and production of H{sub 2} using semiconductor-photocatalytic effect induced by gamma ray from high radioactive waste

    Energy Technology Data Exchange (ETDEWEB)

    Wada, Y; Kawaguchi, K; Myouchin, M [Power Reactor and Nuclear Fuel Development Corp., Tokai, Ibaraki (Japan). Tokai Works

    1996-12-31

    The technology of the radiolytic decomposition of water leading to hydrogen production was demonstrated to explore a new field in the utilization of radiation and radioactive elements. The technology used consisted of a photoassisted catalytic method which has been generally investigated for photocatalysis using a semiconductor and light in an electrochemical study. In our study, gamma radiation from Co-60 was used instead of light, and a significant amount of evolved hydrogen was detected. Our preliminary experiments proved the possibility of converting the energy ionizing radiation (gamma radiation) into chemical energy (hydrogen) using a semiconductor-photocatalytic effect. (author).

  6. External radiation surveillance

    International Nuclear Information System (INIS)

    Antonio, E.J.

    1995-01-01

    This section of the 1994 Hanford Site Environmental Report describes how external radiation was measured, how surveys were performed, and the results of these measurements and surveys. External radiation exposure rates were measured at locations on and off the Hanford Site using thermoluminescent dosimeters (TLD). External radiation and contamination surveys were also performed with portable radiation survey instruments at locations on and around the Hanford Site

  7. External radiation surveillance

    Energy Technology Data Exchange (ETDEWEB)

    Antonio, E.J.

    1995-06-01

    This section of the 1994 Hanford Site Environmental Report describes how external radiation was measured, how surveys were performed, and the results of these measurements and surveys. External radiation exposure rates were measured at locations on and off the Hanford Site using thermoluminescent dosimeters (TLD). External radiation and contamination surveys were also performed with portable radiation survey instruments at locations on and around the Hanford Site.

  8. Design of device for testing in the gamma irradiator; Diseno de dispositivo para pruebas en el irradiador gamma

    Energy Technology Data Exchange (ETDEWEB)

    Mariano H, E

    1991-02-15

    In eves of the recharge of the Gamma Irradiator, JS-6500 it was detected, that there was contamination in the container that housed the pencils of Co-60, coming from Argentina, country to which the ININ buys it recharges. It was determined that the contamination in the container was it interns and after discussing several solution options it was determined to manufacture a device to make a washing of the pencils. It was touch to the Management of Radiological Safety to determine the conceptual design of the device to make the washing and the way of operation of the same one. The Management of Prototypes and Models was responsibility of the mechanical design and its production. (Author)

  9. Effects of gamma radiation on melon read-to-eat

    International Nuclear Information System (INIS)

    Pires, Juliana A.; Polizel, Francine Fernanda; Harder, Marcia N.C.; Silva, Lucia C.A.S.; Arthur, Paula B.; Arthur, Valter

    2013-01-01

    This work comes from the irradiation of Cantaloupe melons (Cucumis melo L.), with the aid of gamma irradiation (Co60) to physical and chemical changes to assess their conservation. The research aimed to evaluate the effects of irradiation on melons, including the possibility of conservation, through pH, acidity, soluble solids and fresh squash. The samples were minimally processed and submitted to gamma radiation Co 60 at doses of 0 (control); 1kGy and 2kGy. Physicochemical analyzes were made in periods of 1, 7 and 14 days after irradiation treatment. On day 1 and day 7, pH levels in irradiated samples had increased compared to control. Since the 14th day, the dose decreased 1kGy equaling the control. Soluble solids showed a statistical gradual decrease according to the increase of dose. The 14th had no significant difference while the 7th the dose was increased. The 1kGy sample decreased in another dose compared to the control. In fresh squash, absent statistics were observed for all samples in the three periods. And for the analysis of titratable acidity, there was observed no significant difference at day 1. There was observed a decrease in the 2kGy and 1kGy dose to 7 days compared to the control. On 14th day, a reduction in the dose of 2kGy and deterioration of 1kGy dose of the sample. Therefore, it demonstrates the irradiation doses of 2kGy, 1kGy physic-chemically alters the Cantaloupe melon pH, soluble solids content and acidity. And the dose of 2kGy is the one that longer preserves samples based on acidity values, greater and smaller values of soluble solids. (author)

  10. ExternE: Externalities of energy Vol. 5. Nuclear

    International Nuclear Information System (INIS)

    Dreicer, M.; Tort, V.; Manen, P.

    1995-01-01

    Since the early 1970s, there has been increased interest in the environmental impacts that are caused by the generation of electricity. The comparative risk assessment studies at that time used mainly deaths and injuries as impact indicators. By the end of the 1980s studies changed to the assessment of the costs imposed on society and the environment that were not included in the market price of the energy produced, the so-called external costs. The preliminary studies that were published set the conceptual basis, grounded in neo-classical economics, for the valuation of the health and environmental impacts that could be assessed. As a consequence of the many questions raised by the methodologies employed by these early studies, Directorate General XII (DG XII) of the Commission of the European Communities established a collaborative research programme with the United States Department of Energy to identify an appropriate methodology for this type of work. Following the completion of this collaboration, the DG XII programme has continued as the ExternE project. The main objective of the work carried out at CEPN was to develop an impact pathway methodology for the nuclear fuel cycle that would be consistent with the methodologies developed for other fuel cycles, without loosing the nuclear-specific techniques required for a proper evaluation. In this way, comparisons between the different fuel cycles would be possible. This report presents the methodology and demonstration of the results in the context of the French nuclear fuel cycle. The United States team at Oak Ridge National Laboratory has previously issued a draft report on the results of their assessment. The French fuel cycle was broken down into 8 separate stages. Reference sites and 1990s technology were chosen to represent the total nuclear fuel cycle, as it exists today. In addition, the transportation of material between the sites was considered. The facilities are assessed for routine operation, except

  11. Gamma irradiation influence on physical properties of milk proteins

    International Nuclear Information System (INIS)

    Ciesla, K.; Salmieri, S.; Lacroix, M.; Le Tien, C.

    2004-01-01

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

  12. Gamma irradiation influence on physical properties of milk proteins

    Energy Technology Data Exchange (ETDEWEB)

    Ciesla, K. E-mail: kciesla@orange.ichtj.waw.pl; Salmieri, S.; Lacroix, M.; Le Tien, C

    2004-10-01

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

  13. Gamma radiation of cotton seeds pre-planting

    International Nuclear Information System (INIS)

    Gulyamov, M-K.; Atadzhanov, M.; Narimov, S.

    1977-01-01

    The study of pre-planting irradiation of the cotton plant seeds with gamma rays is summed up. It is for the first time that for the industrial grades stimulating doses for preplanting gamma irradiation of seeds have been offered depending on the power of a radiation source, time before planting, reproduction and the site of origin of seeds. In the Tashkent area doses stimulating the growth, development, and productivity of the cotton plant G. hirsutum L. for seeds, resting in the dry condition are 0.5-2 krad by Co 60 gamma-rays. The early maturing kinds of the type C-4727 should be irradiated with slightly lowered doses (0.5-1 krad) while the usual types of the kind 108-F require doses nearer to 2 krad. Time from irradiation of the seed to planting influences not only the character of changes in the plants, but also heredity. Study during the vegetation period shows that at a dose of 1 krad a much earlier maturity (by 2 days) is observed for irradiation 10 days before planting. Irradiation 20 days before planting shows considerable delay in maturing and productivity as compared to controls

  14. Development of autonomous gamma dose logger for environmental monitoring

    Energy Technology Data Exchange (ETDEWEB)

    Jisha, N. V.; Krishnakumar, D. N.; Surya Prakash, G.; Kumari, Anju; Baskaran, R.; Venkatraman, B. [Radiological Safety Division, Indira Gandhi Centre for Atomic Research, Kalpakkam 603 102, Tamil Nadu (India)

    2012-03-15

    Continuous monitoring and archiving of background radiation levels in and around the nuclear installation is essential and the data would be of immense use during analysis of any untoward incidents. A portable Geiger Muller detector based autonomous gamma dose logger (AGDL) for environmental monitoring is indigenously designed and developed. The system operations are controlled by microcontroller (AT89S52) and the main features of the system are software data acquisition, real time LCD display of radiation level, data archiving at removable compact flash card. The complete system operates on 12 V battery backed up by solar panel and hence the system is totally portable and ideal for field use. The system has been calibrated with Co-60 source (8.1 MBq) at various source-detector distances. The system is field tested and performance evaluation is carried out. This paper covers the design considerations of the hardware, software architecture of the system along with details of the front-end operation of the autonomous gamma dose logger and the data file formats. The data gathered during field testing and inter comparison with GammaTRACER are also presented in the paper. AGDL has shown excellent correlation with energy fluence monitor tuned to identify {sup 41}Ar, proving its utility for real-time plume tracking and source term estimation.

  15. Development of autonomous gamma dose logger for environmental monitoring.

    Science.gov (United States)

    Jisha, N V; Krishnakumar, D N; Surya Prakash, G; Kumari, Anju; Baskaran, R; Venkatraman, B

    2012-03-01

    Continuous monitoring and archiving of background radiation levels in and around the nuclear installation is essential and the data would be of immense use during analysis of any untoward incidents. A portable Geiger Muller detector based autonomous gamma dose logger (AGDL) for environmental monitoring is indigenously designed and developed. The system operations are controlled by microcontroller (AT89S52) and the main features of the system are software data acquisition, real time LCD display of radiation level, data archiving at removable compact flash card. The complete system operates on 12 V battery backed up by solar panel and hence the system is totally portable and ideal for field use. The system has been calibrated with Co-60 source (8.1 MBq) at various source-detector distances. The system is field tested and performance evaluation is carried out. This paper covers the design considerations of the hardware, software architecture of the system along with details of the front-end operation of the autonomous gamma dose logger and the data file formats. The data gathered during field testing and inter comparison with GammaTRACER are also presented in the paper. AGDL has shown excellent correlation with energy fluence monitor tuned to identify (41)Ar, proving its utility for real-time plume tracking and source term estimation.

  16. Method Validation Procedure in Gamma Spectroscopy Laboratory

    International Nuclear Information System (INIS)

    El Samad, O.; Baydoun, R.

    2008-01-01

    The present work describes the methodology followed for the application of ISO 17025 standards in gamma spectroscopy laboratory at the Lebanese Atomic Energy Commission including the management and technical requirements. A set of documents, written procedures and records were prepared to achieve the management part. The technical requirements, internal method validation was applied through the estimation of trueness, repeatability , minimum detectable activity and combined uncertainty, participation in IAEA proficiency tests assure the external method validation, specially that the gamma spectroscopy lab is a member of ALMERA network (Analytical Laboratories for the Measurements of Environmental Radioactivity). Some of these results are presented in this paper. (author)

  17. [External cephalic version].

    Science.gov (United States)

    Navarro-Santana, B; Duarez-Coronado, M; Plaza-Arranz, J

    2016-08-01

    To analyze the rate of successful external cephalic versions in our center and caesarean sections that would be avoided with the use of external cephalic versions. From January 2012 to March 2016 external cephalic versions carried out at our center, which were a total of 52. We collected data about female age, gestational age at the time of the external cephalic version, maternal body mass index (BMI), fetal variety and situation, fetal weight, parity, location of the placenta, amniotic fluid index (ILA), tocolysis, analgesia, and newborn weight at birth, minor adverse effects (dizziness, hypotension and maternal pain) and major adverse effects (tachycardia, bradycardia, decelerations and emergency cesarean section). 45% of the versions were unsuccessful and 55% were successful. The percentage of successful vaginal delivery in versions was 84% (4% were instrumental) and 15% of caesarean sections. With respect to the variables studied, only significant differences in birth weight were found; suggesting that birth weight it is related to the outcome of external cephalic version. Probably we did not find significant differences due to the number of patients studied. For women with breech presentation, we recommend external cephalic version before the expectant management or performing a cesarean section. The external cephalic version increases the proportion of fetuses in cephalic presentation and also decreases the rate of caesarean sections.

  18. Piezosurgery in External Dacryocystorhinostomy.

    Science.gov (United States)

    Czyz, Craig N; Fowler, Amy M; Dutton, Jonathan J; Cahill, Kenneth V; Foster, Jill A; Hill, Robert H; Everman, Kelly R; Nabavi, Cameron B

    Dacryocystorhinostomy (DCR) can be performed via an external or endoscopic approach. The use of ultrasonic or piezosurgery has been well described for endoscopic DCRs but is lacking for external DCRs. This study presents a case series of external DCRs performed using piezosurgery evaluating results and complications. Prospective, consecutive case series of patients undergoing primary external DCR for lacrimal drainage insufficiency. A standard external DCR technique was used using 1 of 2 piezosurgery systems for all bone incision. All patients received silicone intubation to the lacrimal system. Surgical outcome was measured in terms of patient-reported epiphora as follows: 1) complete resolution, 2) improvement >50%, 3) improvement 50% improvement. There were 4 patients (7%) who had <50% improvement. There was 1 (2%) intraoperative complication and 2 (4%) postoperative complications recorded. Piezourgery is a viable modality for performing external DCRs. The lack of surgical complications shows a potential for decreased soft tissues damage. The surgical success rate based on patient-reported epiphora is similar to those published for mechanical external DCRs. This modality may benefit the novice surgeon in the reduction of soft and mucosal tissue damage.

  19. Cosmic gamma bursts

    International Nuclear Information System (INIS)

    Ehstulin, I.V.

    1980-01-01

    A brief consideration is being given to the history of cosmic gamma burst discovery and modern knowledge of their properties. The time dependence of gamma bursts is described and their possible sources are discussed

  20. Action of fractionated X-irradiation, continuous and a combination of continuous and acute (Co60) γ-irradiation on the catechol-amine content of the cardiac muscle of rats

    International Nuclear Information System (INIS)

    Karpovich, N.V.

    1976-01-01

    Changes in the catechol amine content of the cardiac muscle of white rats have been studied in the course and after the exposure to low-dose X- and gamma radiation. The data obtained show that the changes in the catechol amine content depend not merely on the cumulative dose of the ionizing radiation but also on its type and the time that has passed after irradiation

  1. Effect of Gamma Radiation on Spore Germination and Mycelial Growth of Penicillium Expansum, Post harvest Disease of Apple Fruit

    International Nuclear Information System (INIS)

    Mostafavi, H. A.; Mirmajlessi, S. M.; Mirjalili, S. M.; Fathollahi, H.; Mansouripour, S. M.; Babaei, M.

    2012-01-01

    Blue mold caused by Penicillium expansum causes most of the losses during the storage period in the world. In this study, the inhibition effect of different doses of gamma radiation on spore germination and mycelial growth of Penicillium expansum was investigated. As a result, the Penicillium expansum was recovered from infected apple fruits. In order to evaluate the gamma radiation effect on the spore germination, spore suspension (10 4 spore/ml) exposed to 0, 100, 300 and 600 grey, using Co-60 gamma cell with a dose rate of 0.2 Gy/Sec. Also, a disk of mycelium (0.5 cm 2 ) was removed from the edge of a three-days colony and transferred to PDA plates and irradiated to 0, 1500, 2000, 2500, 3000 and 3500 Gy. The results showed that, the irradiation has completely inhibited the spore germination at 600 Gy. While, a dose of 3000 Gy completely inhibited the mycelial growth of Penicillium expansum.

  2. Effect of gamma irradiation upon the mutation of skin color of the Fuji apple cultivar

    Energy Technology Data Exchange (ETDEWEB)

    Yoshida, Yoshio

    1984-03-01

    The new apple cultivar Fuji was bred at the Morioka Branch, Fruit Tree Research Station, in 1958. Although the quality of the Fuji fruits is high, the skin color is not very attractive. In 1963 and 1964, the Fuji cultivar was irradiated with gamma ray in the growing tree stage and the state of dormant scions. Some promising mutants of the color sport were selected. In 1963, two year old Fuji saplings grafted to Marubakaido were planted in a gamma field of the Institute of Radiation Breeding, and exposed to the dose from a Co-60 source from 200 to 12.5 R per day for 223 days, thereafter they were transplanted in the Morioka Branch in 1964. The dormant scions of the Fuji cultivar were sealed in polyethylene bags, and placed at different distances from a Co-60 source. The treatment in 1963 was at 6000 or 3000 R for one day, and in 1964, at 6000, 3000, 1200 and 600 R for one day, two, five and ten days, respectively, thus the total dose was 6000 R in all cases. Thereafter, they were grafted to Marubakaido. All trees which received over 20,000 R in total died, and those which received less than 5000 R produced no mutant. The scions except 600 R/day x 10 days group produced mutants. 15 color sports and 3 spur type mutants were selected in this experiment. (J.P.N.).

  3. Effect of gamma irradiation upon the mutation of skin color of the 'Fuji' apple cultivar

    International Nuclear Information System (INIS)

    Yoshida, Yoshio

    1984-01-01

    The new apple cultivar ''Fuji'' was bred at the Morioka Branch, Fruit Tree Research Station, in 1958. Although the quality of the Fuji fruits is high, the skin color is not very attractive. In 1963 and 1964, the Fuji cultivar was irradiated with gamma ray in the growing tree stage and the state of dormant scions. Some promising mutants of the color sport were selected. In 1963, two year old Fuji saplings grafted to Marubakaido were planted in a gamma field of the Institute of Radiation Breeding, and exposed to the dose from a Co-60 source from 200 to 12.5 R per day for 223 days, thereafter they were transplanted in the Morioka Branch in 1964. The dormant scions of the Fuji cultivar were sealed in polyethylene bags, and placed at different distances from a Co-60 source. The treatment in 1963 was at 6,000 or 3,000 R for one day, and in 1964, at 6,000, 3,000, 1,200 and 600 R for one day, two, five and ten days, respectively, thus the total dose was 6,000 R in all cases. Thereafter, they were grafted to Marubakaido. All trees which received over 20,000 R in total died, and those which received less than 5,000 R produced no mutant. The scions except 600 R/day x 10 days group produced mutants. 15 color sports and 3 spur type mutants were selected in this experiment. (J.P.N.)

  4. SU-F-303-17: Real Time Dose Calculation of MRI Guided Co-60 Radiotherapy Treatments On Free Breathing Patients, Using a Motion Model and Fast Monte Carlo Dose Calculation

    International Nuclear Information System (INIS)

    Thomas, D; O’Connell, D; Lamb, J; Cao, M; Yang, Y; Agazaryan, N; Lee, P; Low, D

    2015-01-01

    Purpose: To demonstrate real-time dose calculation of free-breathing MRI guided Co−60 treatments, using a motion model and Monte-Carlo dose calculation to accurately account for the interplay between irregular breathing motion and an IMRT delivery. Methods: ViewRay Co-60 dose distributions were optimized on ITVs contoured from free-breathing CT images of lung cancer patients. Each treatment plan was separated into 0.25s segments, accounting for the MLC positions and beam angles at each time point. A voxel-specific motion model derived from multiple fast-helical free-breathing CTs and deformable registration was calculated for each patient. 3D images for every 0.25s of a simulated treatment were generated in real time, here using a bellows signal as a surrogate to accurately account for breathing irregularities. Monte-Carlo dose calculation was performed every 0.25s of the treatment, with the number of histories in each calculation scaled to give an overall 1% statistical uncertainty. Each dose calculation was deformed back to the reference image using the motion model and accumulated. The static and real-time dose calculations were compared. Results: Image generation was performed in real time at 4 frames per second (GPU). Monte-Carlo dose calculation was performed at approximately 1frame per second (CPU), giving a total calculation time of approximately 30 minutes per treatment. Results show both cold- and hot-spots in and around the ITV, and increased dose to contralateral lung as the tumor moves in and out of the beam during treatment. Conclusion: An accurate motion model combined with a fast Monte-Carlo dose calculation allows almost real-time dose calculation of a free-breathing treatment. When combined with sagittal 2D-cine-mode MRI during treatment to update the motion model in real time, this will allow the true delivered dose of a treatment to be calculated, providing a useful tool for adaptive planning and assessing the effectiveness of gated treatments

  5. SU-E-T-94: An Advanced Rotating Gamma Ray System for Stereotactic Radiosurgery

    Energy Technology Data Exchange (ETDEWEB)

    Ma, C; Chibani, O; Li, J; Chen, L [Fox Chase Cancer Center, Philadelphia, PA (United States); Mora, G [Universidade de Lisboa, Codex, Lisboa (Portugal)

    2015-06-15

    Purpose: Co-60 beams have unique dosimetric properties that are ideally suited for cranial treatments. Co-60 sources with cone-shaped collimators provide conformal dose distributions allowing for ablative treatments with rapid dose falloff to spare nearby critical structures. This work investigates a novel, image-guided, rotational Gamma ray system that provides both superior dose conformity/gradient and accurate stereotaxy for stereotactic radiosurgery (SRS). Methods: The SupeRay system (Cyber Medical Corp., China) consists of a rotating source chamber containing 30 gamma sources focusing at the isocenter with 4 collimators measuring 3, 4, 8 and 16mm in diameter. A novel switch design enables the 30 Gamma sources to be turned off at any arbitrarily selected 60° interval in order to avoid critical structures. The 3D treatment couch provides automatic treatment positioning between individual shots and the kV imaging system provides orthogonal images with a spatial resolution of 0.24mm to facilitate target localization. Monte Carlo simulations were used to compute dose distributions and compare with measurements and other Gamma ray SRS systems. Results: Monte Carlo results confirmed the SupeRay design parameters including output factors and 3D dose distributions. Its beam penumbra/dose gradient is similar to or slightly better than that of the Elekta Gamma Knife. The penumbra in the (x,y,z) direction was (7.38mm,7.38mm,3.86mm) for the 16mm collimator, (4.83mm,4.83mm,3.12mm) for the 8mm collimator, and (3.03mm,3.03mm,2.38mm) for the 4mm collimator, respectively, on the SupeRay system while it was (9.5mm,10.0mm,2.9mm), (4.3mm,4.3mm,2.9mm) and (3.2mm,3.2mm,1.9mm) for the same collimator sizes, respectively, on the Perfexion system. The kV imaging system together with a non-invasive relocatable frame provides accurate target localization (<0.5mm) for cases requiring multiple treatment fractions. Conclusion: Because of the unique dosimetric properties of Co-60 sources

  6. Low level GAMMA0 spectrometry by beta-gamma coincidence

    International Nuclear Information System (INIS)

    Grigorescu, E.L.; Luca, A.; Razdolescu, A.C.; Ivan, C.

    1999-01-01

    Low level gamma spectrometry has a wide application, especially in environmental monitoring. Two variants, based on a beta-gamma coincidence technique, were studied. The equipment was composed of a beta detector and a Ge(Li) gamma detector (6% - relative efficiency), with the associated electronics. The gamma rays are recorded by the multichannel analyzer (4096 channels) only if the associated beta particles, which precede the gamma transitions, are registered in coincidence. Two types of beta detectors were used: plastic and liquid scintillators. In both cases, an external lead shield of 5 cm thick was used. The integral gamma background (50-1700 KeV) was reduced about 85 and 50 times, respectively. The corresponding MDA (Minimum Detectable Activity) values decreased about 1.5 and (3-7) times, respectively. The 2π sr plastic beta detector was placed on top the Ge(Li). The sample was inserted between the two detectors. The measurement time was 10 4 s. A 4π sr detector, built of the same material, was also studied, but it proved to be less advantageous because the background was reduced only 16 times; for a MDA reduction similar with that of the 2π sr variant, a longer measurement was needed (3.10 4 s). The other type of beta detector used, was a liquid scintillator. The dissolving of the samples in scintillator ensures a 4π sr measurement geometry. The vials with scintillator (10 ml volume) were placed on top the Ge(Li) and visualised by the photocathode of a phototube. This setup was surrounded by an enclosure which prevent the light penetration. The measurement time was 10 4 s. The only difficulty encountered in this low level measurement method is the accurate determination of the beta efficiency. A limitation is the possibility to measure only small mass samples. These variants are more simple and cheaper than others, previously studied. The advantage of the method is obvious when, instead of low MDA values, shorter measurement times are preferred. The

  7. Metrological aspects of radiochemical methods for determining activity of gamma-emitting nuclides

    International Nuclear Information System (INIS)

    Shcherbakov, B.Y.

    1986-01-01

    The author considers the problem of metrological compatibility of the two stages in the radiochemical method of determining the activity of a gamma-emitting nuclide: chemical isolation of the nuclide and radiometric measurement of its activity. The authors show that preparation of the specimen in liquid form provides for important advantages compared with the traditional application of the solid residue onto a flat substate. The work here is of interest for analytical chemists who are involved with determination of the activity of gamma emitting nuclides such as Ru 103, Rh 106, Sn 113, Cs 134, Cs 137, La 140, Ce 141, Ce 144, Hg 203, Na 24, Mn 54, Fe 59, Co 60, Zn 65, Zr 95, and Nb 95, for example, in waste water or in emissions to the atmosphere, with the goal of protecting the environment

  8. Pollen-gamma irradiation on pineapple and pollination using irradiated pollen

    International Nuclear Information System (INIS)

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

    1997-01-01

    In order to try to induce haploid plants, pineapple (Ananas comosus (L.) ;err.) pollen grains were gamma-rays irradiated with a Co 60 source at rates of doses from 0 to 300 Gy. The effect of gamma-rays on the generative-nucleus division and vitro pollen viability as well as, seed contents and plantlets obtained after pollinations was analysed. The were reducing in the division frequencies of generative nucleus at all assayed doses. The LD50 was achieved among 200 and 250 Gy. There were not differences on pollen viability in the rates of assayed doses. Seed contents were dose-dependent. The percentages of seed full and seed containing only embryos decreases at increasing of irradiation doses. Contrary effect was observed on the seed empty. Some plantlets regenerated from the different irradiation doses showed phenotypes with small and leaves and short inter nodes

  9. Effect of single and combined treatment with gamma rays and some chemical mutagens in rice

    International Nuclear Information System (INIS)

    Lyong Van Hin; Mekhandzhiev, A.; Murzova, P.; Chilikov, I.

    1991-01-01

    Dry rice seeds of 3 cvs and 2 lines have been irradiated (Co 60 , 10 krad) and treated with 0.0012% sodium azide (NaN 3 ) and 0.2% ethylmethanesulfonate (EMS) in definite combinations. It is found that chlorophyll mutations are less frequent after single gamma irradiation. Sodium azide produces a higher percentage of mutations than EMS. Highest mutation frequency has been observed following combined treatment with gamma rays and chemical mutagens. The combined treatment has resulted in a considerably higher mutation effect than the theoretically expected one in the lines Nora and Mega, and in cv. Krasnodarski 424. Highest mutation spectrum has been found in cv. Krasnodarski 424 and in Nora line following combined treatment. 1 tab., 5 figs., 20 refs

  10. Recent results on the effect of gamma radiation on the durability and microstructure of DWPF glass

    International Nuclear Information System (INIS)

    Bibler, N.E.; Tosten, M.H.; Beam, D.C.

    1989-01-01

    The effect of gamma radiation on the durability and microstructure of a simulated nuclear waste glass from the Savannah River Site has been carefully investigated. Three large pieces of glass were irradiated with a Co-60 source to three doses up to a maximum dose of 3.1 x 10 10 rad. Internal samples of the large pieces of irradiated and unirradiated glass were leached in deionized water to investigate durability changes and were examined by transmission electron microscopy (TEM) to investigate microstructure changes. Leach tests were performed in triplicate at 90 degree C with crushed glass samples in deionized water. A statistical analysis of the results indicated to the 95% confidence level that the radiation did not affect the glass durability. Careful examination by TEM indicated no effect of gamma radiation on the microstructure of the glass although severe damage could be induced by the electron beam from the microscope. 19 refs., 2 figs., 3 tabs

  11. Effect of gamma radiation on lipids by the TBARS and NMR

    International Nuclear Information System (INIS)

    Silva, Adriana Cristina de Oliveira; Cortez, Marco Antonio Sloboda; Marsico, Eliane Teixeira; Guimaraes, Carlos Frederico; Jesus, Edgar Francisco Oliveira de

    2011-01-01

    The aim of this work was to study the effect of gamma radiation on lipids by TBARS and NMR. The samples of raw whole milk were subjected to gamma radiation from Co 60 in doses of 1, 2 and 3 kGy and the production of rancidity was studied through Nuclear Magnetic Resonance (NMR) and Thiobarbituric Acid Test (2-TBARS). The TBARS values increased according to the intensity of the radiation dose applied at the samples, demonstrating correlation between the radiation dose and the production of lipid oxidation. This was confirmed by NMR with the formation of peaks of aldehydes and ketones that were small and similar in the doses of 1 and 2 kGy. In the dose of 3 kGy, the total degradation of milk fat was observed. A correlation between the NMR and 2-TBA was detected. (author)

  12. Calculation of reasonable exemption levels for surface contamination by measuring overall gamma ray

    International Nuclear Information System (INIS)

    Ogino, Haruyuki; Hattori, Takatoshi

    2008-01-01

    The present regulation on surface contamination [Bq/cm 2 ] is determined from a simple radiological model for the most hazardous radionuclides (Pu-239 for alpha emitters and Sr-90 for beta emitters) and its extremely conservative model is applied for all other alpha and beta emitters. In this study, reasonable exemption levels for surface contamination are calculated for each radionuclide by adopting an original radiological dose evaluation method for surface contamination that can be applied in radiation safety, transport safety and waste safety. Furthermore, a new concept of judging the exemption by estimating the overall contamination [Bq] on the objects from the measurement of gamma ray has been designed and a reasonable value was derived. We conclude that the overall exemption levels obtained by gamma ray measurement can be one order smaller than those obtained by the conventional method for some radionuclides, such as Mn-54, Co-60, Nb-94, Cs-134, Cs-137, Eu-152 and Eu-154. (author)

  13. Manual on panoramic gamma irradiators (categories 2 and 4). Incorporating: Applications guide, procedures guide, basics guide

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-03-01

    The document is the first revision of a previous one published in 1993 to provide guidance on the safe use and regulation of self-contained gamma irradiators (Co-60 or Cs-137 sources) in different fields of application. It includes three parts: Applications Guide, which describes the main applications of self-contained gamma irradiators, the type of equipment, including safety systems, operation and maintenance, and how to deal with incidents. Procedures Guide, which gives step by step instructions on how to carry out the practice. Basics Guide, which explains the fundamentals of radiation, the system of units, interaction of radiation with matter radiation detection, etc. The manual is aimed primarily at persons handling such radiation sources on a daily routine basis, as well as at the competent authorities for training of workers in radiation protection or for setting up local radiation protection rules.

  14. Manual on panoramic gamma irradiators (categories 2 and 4). Incorporating: Applications guide, procedures guide, basics guide

    International Nuclear Information System (INIS)

    1996-01-01

    The document is the first revision of a previous one published in 1993 to provide guidance on the safe use and regulation of self-contained gamma irradiators (Co-60 or Cs-137 sources) in different fields of application. It includes three parts: Applications Guide, which describes the main applications of self-contained gamma irradiators, the type of equipment, including safety systems, operation and maintenance, and how to deal with incidents. Procedures Guide, which gives step by step instructions on how to carry out the practice. Basics Guide, which explains the fundamentals of radiation, the system of units, interaction of radiation with matter radiation detection, etc. The manual is aimed primarily at persons handling such radiation sources on a daily routine basis, as well as at the competent authorities for training of workers in radiation protection or for setting up local radiation protection rules

  15. Computer program SCAP-BR for gamma-ray streaming through multi-legged ducts

    International Nuclear Information System (INIS)

    Byoun, T.Y.; Babel, P.J.; Dajani, A.T.

    1977-01-01

    A computer program, SCAP-BR, has been developed at Burns and Roe for the gamma-ray streaming analysis through multi-legged ducts. SCAP-BR is a modified version of the single scattering code, SCAP, incorporating capabilities of handling multiple scattering and volumetric source geometries. It utilizes the point kernel integration method to calculate both the line-of-sight and scattered gamma dose rates by employing the ray tracing technique through complex shield geometries. The multiple scattering is handled by a repeated process of the single scatter method through each successive scatter region and collapsed pseudo source meshes constructed on the relative coordinate systems. The SCAP-BR results have been compared with experimental data for a Z-type (three-legged) concrete duct with a Co-60 source placed at the duct entrance point. The SCAP-BR dose rate predictions along the duct axis demonstrate an excellent agreement with the measured values

  16. Gamma ray astronomy

    International Nuclear Information System (INIS)

    Broomhead, Laurent.

    1980-01-01

    The nuclear gamma astronomy is presented, in particular the Gamma Ray Observatory, an enormous eight tonnes machine fitted with gamma telescopes, scheduled for launching around 1985. It is thereby hoped to study the natural nuclear reactions which occur when stars explode [fr

  17. Automated External Defibrillator

    Science.gov (United States)

    ... leads to a 10 percent reduction in survival. Training To Use an Automated External Defibrillator Learning how to use an AED and taking a CPR (cardiopulmonary resuscitation) course are helpful. However, if trained ...

  18. Energy policy and externalities

    International Nuclear Information System (INIS)

    Bertel, E.; Fraser, P.

    2002-01-01

    External costs of energy have been assessed in a number of authoritative and reliable studies based upon widely accepted methodologies such as life cycle analysis (LCA). However, although those costs are recognised by most stakeholders and decision makers, results from analytical work on externalities and LCA studies are seldom used in policy making. The International Energy Agency (IEA) and the Nuclear Energy Agency (NEA) convened a joint workshop in November 2001 to offer experts and policy makers an opportunity to present state-of-the-art results from analytical work on externalities and debate issues related to the relevance of external costs and LCA for policy-making purposes. The findings from the workshop highlight the need for further work in the field and the potential rote of international organisations like the IEA and the NEA in this context. (authors)

  19. Externally Verifiable Oblivious RAM

    Directory of Open Access Journals (Sweden)

    Gancher Joshua

    2017-04-01

    Full Text Available We present the idea of externally verifiable oblivious RAM (ORAM. Our goal is to allow a client and server carrying out an ORAM protocol to have disputes adjudicated by a third party, allowing for the enforcement of penalties against an unreliable or malicious server. We give a security definition that guarantees protection not only against a malicious server but also against a client making false accusations. We then give modifications of the Path ORAM [15] and Ring ORAM [9] protocols that meet this security definition. These protocols both have the same asymptotic runtimes as the semi-honest original versions and require the external verifier to be involved only when the client or server deviates from the protocol. Finally, we implement externally verified ORAM, along with an automated cryptocurrency contract to use as the external verifier.

  20. The effect of vitamin A and vitamin E against Co60 radiationinduced oxidative injury%维生素A和E抗辐射氧化损伤作用的研究

    Institute of Scientific and Technical Information of China (English)

    王欣; 王璐; 陈宏莉; 柏桦; 王钊; 刘江正; 海春旭

    2011-01-01

    OBJECTIVE: To study the antagonistic effects of vitamin A and vitamin E against Co60 radiationinduced oxidative injury. METHOD: Experiment 1: Rats were divided into five groups, including control,radiation, radiation + vitamin A, radiation + vitamin E and radiation + half dose of vitamin A and vitamin E. Beforeexposure to radiation, rats were treated with intragastrically with 30 mg/kg vitamin A, 30 mg/kg vitamin E, or 15 mg/kgvitamin A + 15 mg/kg vitamin E. Experiment 2: Rats were divided into seven groups, including control,radiation, radiation + 30 mg/kg vitamin E, radiation + 30 mg/kg vitamin E + different concentrations of vitaminA, ranging from 2.5 mg/kg to 20 mg/kg. Before the exposure to radiation, rats received intragastrically 30 mg/kg vitaminE, or 30 mg/kg vitamin E + different concentration of vitamin A. At day 7, rats were exposed to 6 Gy Co60 radiation. Atday 10, the rats were sacrificed, and serum and tissues were collected for analysis. RESULTS: Vitamin A and vitaminE alone could protect the rats against the injury induced by radiation. When the concentration of vitamin E was fixed at 30mg/kg, different concentrations of vitamin A resulted in the increase of MDA, the decrease of SOD and CAT activities and the content of vitamin E, in a dose-dependent manner. CONCLUSION: Under certain concentration, vitamin A and vitamin E could produce antagonistic effect.%目的:探讨维生素A(vitamin A,VA)和维生素E(vitamin E,VE)抗辐射氧化损伤的相互作用.方法:实验分为VA、VE抗辐射氧化损伤实验和VA、VE联合应用抗辐射氧化损伤实验.前者设阴性对照组、阳性对照组、VA(30mg/kg)组、VE(30 mg/kg)组及VA+VE半量(均为15 mg/kg)联合用药组.各组大鼠每天用受试物灌胃1次,连续灌胃6d,第7天除阴性对照组外其它各组大鼠均以6Gy的60Co照射,再继续灌胃3 d后处死大鼠,取血、脑和肝组织,测定MDA、SOD、CAT等指标.VA、VE联合应用抗辐射氧化损伤实验设阴性对

  1. Automated TLD system for gamma radiation monitoring

    International Nuclear Information System (INIS)

    Nyberg, P.C.; Ott, J.D.; Edmonds, C.M.; Hopper, J.L.

    1979-01-01

    A gamma radiation monitoring system utilizing a commercially available TLD reader and unique microcomputer control has been built to assess the external radiation exposure to the resident population near a nuclear weapons testing facility. Maximum use of the microcomputer was made to increase the efficiency of data acquisition, transmission, and preparation, and to reduce operational costs. The system was tested for conformance with an applicable national standard for TLD's used in environmental measurements

  2. Reactor gamma spectrometry: status

    International Nuclear Information System (INIS)

    Gold, R.; Kaiser, B.J.

    1979-01-01

    Current work is described for Compton Recoil Gamma-Ray Spectrometry including developments in experimental technique as well as recent reactor spectrometry measurements. The current status of the method is described concerning gamma spectromoetry probe design and response characteristics. Emphasis is given to gamma spectrometry work in US LWR and BR programs. Gamma spectrometry in BR environments are outlined by focussing on start-up plans for the Fast Test Reactor (FTR). Gamma spectrometry results are presented for a LWR pressure vessel mockup in the Poolside Critical Assembly (PCA) at Oak Ridge National Laboratory

  3. Coupling External Radiation Transport Code Results to the GADRAS Detector Response Function

    International Nuclear Information System (INIS)

    Mitchell, Dean J.; Thoreson, Gregory G.; Horne, Steven M.

    2014-01-01

    Simulating gamma spectra is useful for analyzing special nuclear materials. Gamma spectra are influenced not only by the source and the detector, but also by the external, and potentially complex, scattering environment. The scattering environment can make accurate representations of gamma spectra difficult to obtain. By coupling the Monte Carlo Nuclear Particle (MCNP) code with the Gamma Detector Response and Analysis Software (GADRAS) detector response function, gamma spectrum simulations can be computed with a high degree of fidelity even in the presence of a complex scattering environment. Traditionally, GADRAS represents the external scattering environment with empirically derived scattering parameters. By modeling the external scattering environment in MCNP and using the results as input for the GADRAS detector response function, gamma spectra can be obtained with a high degree of fidelity. This method was verified with experimental data obtained in an environment with a significant amount of scattering material. The experiment used both gamma-emitting sources and moderated and bare neutron-emitting sources. The sources were modeled using GADRAS and MCNP in the presence of the external scattering environment, producing accurate representations of the experimental data.

  4. GammaWorkshops Proceedings

    International Nuclear Information System (INIS)

    Ramebaeck, H.; Straelberg, E.; Klemola, S.; Nielsen, Sven P.; Palsson, S.E.

    2012-01-01

    Due to a sparse interaction during the last years between practioners in gamma ray spectrometry in the Nordic countries, a NKS activity was started in 2009. This GammaSem was focused on seminars relevant to gamma spectrometry. A follow up seminar was held in 2010. As an outcome of these activities it was suggested that the 2011 meeting should be focused on practical issues, e.g. different corrections needed in gamma spectrometric measurements. This three day's meeting, GammaWorkshops, was held in September at Risoe-DTU. Experts on different topics relevant for gamma spectrometric measurements were invited to the GammaWorkshops. The topics included efficiency transfer, true coincidence summing corrections, self-attenuation corrections, measurement of natural radionuclides (natural decay series), combined measurement uncertainty calculations, and detection limits. These topics covered both lectures and practical sessions. The practical sessions included demonstrations of tools for e.g. corrections and calculations of the above meantioned topics. (Author)

  5. Improvement of colour strength and colourfastness properties of gamma irradiated cotton using reactive black-5

    International Nuclear Information System (INIS)

    Ahmad Bhatti, Ijaz; Adeel, Shahid; Nadeem, Raziya; Asghar, Toheed

    2012-01-01

    The dyeing behaviour of gamma irradiated cotton fabric using Reactive Black-5 dye powder has been investigated. The mercerized, bleached and plain weaved cotton fabric was irradiated to different absorbed doses of 100, 200, 300, 400, 500 and 600 Gy using Co-60 gamma irradiator. Dyeing was performed using irradiated and un-irradiated cotton with dye solutions. The dyeing parameters such as temperature of dyeing, time of dyeing and pH of dyeing solutions were optimised. The colour strength values of dyed fabrics were evaluated by comparing irradiated and un-irradiated cotton in CIE Lab system using Spectra flash SF650. Methods suggested by International Standard Organisation (ISO) were employed to study the effect of gamma irradiation on the colourfastness properties of dyed fabric. It is found that gamma irradiated cotton dyed with Reactive Black-5 has not only improved the colour strength but also enhanced the rating of fastness properties. - Highlights: ► Optimum absorbed dose for cotton is 500 Gy using un-irradiated Reactive Black-5. ► Optimum dyeing conditions: 60 °C, 30 min and dyeing pH is10. ► At optimum conditions colour strength and fastness properties are enhanced. ► Gamma irradiation can improve dyeing characters of other dyed fabrics.

  6. Quantitative estimations of the efficiency of stabilization and lowering of background in gamma-spectrometry of environment samples

    International Nuclear Information System (INIS)

    Pop, O.M.; Stets, M.V.; Maslyuk, V.T.

    2015-01-01

    We consider a gamma-spectrometric complex of IEP of the NAS of Ukraine, where a passive multilayer external defense is used (complex has been made in 1989). We have developed and investigated a system of stability and lowering of background in the gamma-spectrometric complex. As metrological coefficients, the efficiency factor of defense are considered, the calculation and analysis of which show that their values are different for different energies of gamma-quanta and gamma-active nuclides

  7. Malignant external otitis

    International Nuclear Information System (INIS)

    Dupuch, K.M.; Iryboz, T.; Firat, M.; Levy, C.; Tubiana, J.M.

    1991-01-01

    This paper illustrates the value of CT and MR in early diagnosis and spread of malignant external otitis. The authors retrospectively analyzed 15 patients with proved malignant external otitis examined with postcontrast high-resolution CT (15/15) and MR (6/15) (T1- and T2-weighting). Gallium studies were done in 6/15 patients. Early diagnosis was made when CT demonstrated a soft-tissue mass of the external auditory canal associated with scattered zones of cortical bone erosions (13/15). Spread of the disease was better delineated by MR than CT, especially skull base extension (6/15). Temporomandibular joint involvement with extension into parotid or/and masticator spaces 6/15 was as well detected with CT as with MR. If CT remains the first and best procedure for diagnosis, MR - despite its cost - appears a good procedure to depict exact anatomic spread, allowing therapeutic management

  8. Productivity Change and Externalities

    DEFF Research Database (Denmark)

    Kravtsova, Victoria

    2014-01-01

    This paper contributes to the analysis of the impact of externalities on the host country's total factor productivity by taking into account different dimensions of spillover effects. Namely, engagement in exporting and foreign ownership is generally perceived as being beneficial to individual...... firms and the economy as a whole. The approach used in the current research accounts for different internal as well as external factors that individual firms face and evaluates the effect on changes in productivity, technology as well as the efficiency of domestic firms. The empirical analysis focuses...... on Hungary. While the country leads the group of post-socialist countries in the amount of attracted foreign direct investments (FDI) the effect of this policy on the economy remains unclear. The research finds that different externalities play a different role in productivity, technological and efficiency...

  9. Externality or sustainability economics?

    International Nuclear Information System (INIS)

    Bergh, Jeroen C.J.M. van den

    2010-01-01

    In an effort to develop 'sustainability economics' Baumgaertner and Quaas (2010) neglect the central concept of environmental economics-'environmental externality'. This note proposes a possible connection between the concepts of environmental externality and sustainability. In addition, attention is asked for other aspects of 'sustainability economics', namely the distinction weak/strong sustainability, spatial sustainability and sustainable trade, distinctive sustainability policy, and the ideas of early 'sustainability economists'. I argue that both sustainability and externalities reflect a systems perspective and propose that effective sustainability solutions require that more attention is given to system feedbacks, notably other-regarding preferences and social interactions, and energy and environmental rebound. The case of climate change and policy is used to illustrate particular statements. As a conclusion, a list of 20 insights and suggestions for research is offered. (author)

  10. Metasurface external cavity laser

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Luyao, E-mail: luyaoxu.ee@ucla.edu; Curwen, Christopher A.; Williams, Benjamin S. [Department of Electrical Engineering, University of California, Los Angeles, California 90095 (United States); California NanoSystems Institute, University of California, Los Angeles, California 90095 (United States); Hon, Philip W. C.; Itoh, Tatsuo [Department of Electrical Engineering, University of California, Los Angeles, California 90095 (United States); Chen, Qi-Sheng [Northrop Grumman Aerospace Systems, Redondo Beach, California 90278 (United States)

    2015-11-30

    A vertical-external-cavity surface-emitting-laser is demonstrated in the terahertz range, which is based upon an amplifying metasurface reflector composed of a sub-wavelength array of antenna-coupled quantum-cascade sub-cavities. Lasing is possible when the metasurface reflector is placed into a low-loss external cavity such that the external cavity—not the sub-cavities—determines the beam properties. A near-Gaussian beam of 4.3° × 5.1° divergence is observed and an output power level >5 mW is achieved. The polarized response of the metasurface allows the use of a wire-grid polarizer as an output coupler that is continuously tunable.

  11. beta. and. gamma. -comparative dose estimates on Enewetak Atoll

    Energy Technology Data Exchange (ETDEWEB)

    Crase, K.W.; Gudiksen, P.H.; Robison, W.L. (California Univ., Livermore (USA). Lawrence Livermore National Lab.)

    1982-05-01

    Enewetak Atoll in the Pacific is used for atmospheric testing of U.S. nuclear weapons. Beta dose and ..gamma..-ray exposure measurements were made on two islands of the Enewetak Atoll during July-August 1976 to determine the ..beta.. and low energy ..gamma..-contribution to the total external radiation doses to the returning Marshallese. Measurements were made at numerous locations with thermoluminescent dosimeters (TLD), pressurized ionization chambers, portable NaI detectors, and thin-window pancake GM probes. Results of the TLD measurements with and without a ..beta..-attenuator indicate that approx. 29% of the total dose rate at 1 m in air is due to ..beta..- or low energy ..gamma..-contribution. The contribution at any particular site, however, is reduced by vegetation. Integral 30-yr external shallow dose estimates for future inhabitants were made and compared with external dose estimates of a previous large scale radiological survey. Integral 30-yr shallow external dose estimates are 25-50% higher than whole body estimates. Due to the low penetrating ability of the ..beta..'s or low energy ..gamma..'s, however, several remedial actions can be taken to reduce the shallow dose contribution to the total external dose.

  12. beta- and gamma-Comparative dose estimates on Eniwetok Atoll

    Energy Technology Data Exchange (ETDEWEB)

    Crase, K.W.; Gudiksen, P.H.; Robison, W.L.

    1982-05-01

    Eniwetok Atoll is one of the Pacific atolls used for atmospheric testing of U.S. nuclear weapons. Beta dose and gamma-ray exposure measurements were made on two islands of the Eniwetok Atoll during July-August 1976 to determine the beta and low energy gamma-contribution to the total external radiation doses to the returning Marshallese. Measurements were made at numerous locations with thermoluminescent dosimeters (TLD), pressurized ionization chambers, portable NaI detectors, and thin-window pancake GM probes. Results of the TLD measurements with and without a beta-attenuator indicate that approx. 29% of the total dose rate at 1 m in air is due to beta- or low energy gamma-contribution. The contribution at any particular site, however, is somewhat dependent on ground cover, since a minimal amount of vegetation will reduce it significantly from that over bare soil, but thick stands of vegetation have little effect on any further reductions. Integral 30-yr external shallow dose estimates for future inhabitants were made and compared with external dose estimates of a previous large scale radiological survey (En73). Integral 30-yr shallow external dose estimates are 25-50% higher than whole body estimates. Due to the low penetrating ability of the beta's or low energy gamma's, however, several remedial actions can be taken to reduce the shallow dose contribution to the total external dose.

  13. The External Mind

    DEFF Research Database (Denmark)

    , Extended Mind and Distributed Cognition by Claudio Paolucci pp. 69-96 The Social Horizon of Embodied Language and Material Symbols by Riccardo Fusaroli pp. 97-123 Semiotics and Theories of Situated/Distributed Action and Cognition: a Dialogue and Many Intersections by Tommaso Granelli pp. 125-167 Building......The External Mind: an Introduction by Riccardo Fusaroli, Claudio Paolucci pp. 3-31 The sign of the Hand: Symbolic Practices and the Extended Mind by Massimiliano Cappuccio, Michael Wheeler pp. 33-55 The Overextended Mind by Shaun Gallagher pp. 57-68 The "External Mind": Semiotics, Pragmatism...

  14. PID controller simulator software for DC motor of gamma scanning

    International Nuclear Information System (INIS)

    Arjoni Amir

    2008-01-01

    Mostly PID controller (Proportional-Integral-Derivative) has been used in industry. For certain applications, it can be used as a Proportional (P) model only, or as a Proportional-Integral (PI) model. The aim of this paper is to design a PID controller simulator software for DC motor which is used in gamma scanning system. A DC motor is described as a plant of SISO (Single Input Single Output) which is used for pulling down the load (detector + casing) and gamma radiation source (Co-60 + container) by using sling cable. A DC motor consist of an armature and a rotor, the equivalent circuit of DC motor is shown in a transfer function equation between output parameter (angular speed DC motor) and input parameter (voltage of DC motor). Methods used for the process of PID controller design is to arrange the PID controller parameter (Kc, Ti, Td) so that there are more PID controller transfer function model which are able to control angular speed of DC motor in stable condition, as design criteria requirement is needed. Design criteria requirement for control system are the settling time < 3 second, overshoot < 5%, rise time = 0.25 second, steady state gain = 1 and peak time < 3 second with step response reference 1 rad/second. The result of simulation gives several models of PID controller in function transfer equation which is similar with design criteria requirement in a equation of function transfer of order 2 for numerator and order 1 for denominator. (author)

  15. Gamma scan technique for detecting coupon inside the mother pipeline

    International Nuclear Information System (INIS)

    Rasif Mohd Zain; Roslan Yahya; Mohamad Rabaie Shari; Airwan Affandi Mahmood; Mior Ahmad Khusaini Adnan

    2012-01-01

    Many times a year natural gas transmission and distribution companies need to make new connections to pipelines to expand or modify their existing system through hot tapping procedure. This procedure involves the installation of a new pipeline connection while the pipeline remains in service, flowing natural gas under pressure. The hot tap procedure includes attaching a branch connection and valve on the outside of an operating pipeline, and then cutting out the pipe-line wall within the branch and removing the wall section, which is called object of coupon through the valve. During the hot tapping process a critical problems occurred when a coupon fell into the mother pipeline. To overcome this problem, a gamma-ray absorption technique was chosen whereby a mapping technique will be done to detect the coupon position. The technique is non-destructive as it applies Co-60 (5 mCi) as a radioisotope sealed source to emit gamma radiation and a NaI(Tl) scintillation as detector. The result provided a visible representation of density profile inside pipeline where the coupon location can be located. This paper provides the detail of the technique used and presents the result obtained. (author)

  16. 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)

  17. Use of gamma spectrometry for analysis of three reference materials

    International Nuclear Information System (INIS)

    Kinova, L.

    2004-01-01

    All reference materials (Reference material A: weight = 49.23 g; Reference material B: weight = 36.08 g; Reference material C: weight = 26.18 g) were packed in 50 cm 3 polypropylene vials, sealed and measured consecutively three times at intervals of the average of 25 days. Low background gamma spectrometry system: HPGe detector with high energy resolution (FWHM for 1332 KeV of Co-60 is 1.9 KeV, Relative counting efficiency for the same energy is 21 %) was used. Results: All materials are of low activity and must be measured for a long time.The highest specific activity of a man-made radionuclides Cs-137 and Am-241 is in the material A. An instrumentally measurable activity of Pb-210 also can be observed in this material. Medium values are in the material B. The reference material C according to the specific activity seems to be a low natural radioactivity material with highest activity of natural nuclides Th-232 and Pa-234 (progeny of U-238). Conclusions: Gamma spectrometry is an useful tool for initial measurement of materials with low radioactivity. Such measurements give an orientation for the nuclides content and approximate activity in the material for the following radiochemical determinations

  18. Effect of large dose gamma-ray irradiation on polyimide

    International Nuclear Information System (INIS)

    Morita, Yohsuke; Watanabe, Kiyoshi; Yagyu, Hideki.

    1988-01-01

    In the radiation environment of atomic energy, space and so on, with the heightening of the performance of equipment, the organic materials having the radiation resistance up to several hundreds MGy have been demanded. Polyimide is one of a small number of the polymers which are considered to be applicable to such environment. However, actually the characteristics as the insulator for such large dose radiation environment have not been sufficiently verified. In this study, the gamma-ray of as large dose as 100 MGy was irradiated on the polyimides having different chemical structure in the air and in nitrogen, and the change of their mechanical and electrical characteristics was elucidated, at the same time, the structural change was examined. The four kinds of polyimides used for the experiment were three kinds of thermosetting type and thermoplastic polyether imide. Co-60 gamma-ray was irradiated at the dose rate of 17 kGy/h at room temperature. The tensile properties, volume resistivity, dielectric tangent, gel fraction, glass transition temperature and IR spectra were examined. In the air, the characteristics lowered by large dose irradiation due to the severance of main chains. In nitrogen, the deterioration was extremely slight, and cross-linking occurred. (K.I.)

  19. Large area self-powered gamma ray detector

    International Nuclear Information System (INIS)

    LeVert, F.E.

    1994-01-01

    The purpose of this research was to develop a large area self-powered gamma detector (LASPGD) capable of detecting the movement of sealed radiation sources into and out of industrial radiographic units and to construct a prototype source position monitor (SPM) for these units utilizing the LASPGD. Prototype isotropic and directional LASPGDs, with solid and inert gas dielectrics, were developed and extensively tested using calibrated gamma sources (i.e., Cs-137, and Co-60). The sensitivities of the isotropic detectors, with inert gas dielectrics, were found to be approximately a factor of ten greater than those measured for the solid dielectric LASPGDs. Directionally sensitive self-powered detectors were found to exhibit a forward-to-back hemispherical sensitivity ratio of approximately 2 to 1. Industrial radiographic units containing Ir-192 sources with different activities were used to test the performance of the SPM. The SPM, which utilized a gas dielectric LASPGD, performed as designed. That is, the current generated in the LASPGD was converted to a voltage, amplified and used to control the on/off state of an incandescent lamp. The incandescent lamp, which functions as the source/out warning indicator, flashes at a rate of one flash per second when the source is in use (i.e. out of its shield)

  20. Externalities - an analysis using the EU ExternE-results

    International Nuclear Information System (INIS)

    2003-10-01

    The EU project ExternE quantified the externalities for the different energy technologies. In this work, the ExternE results are used in a MARKAL-analysis for the Nordic countries. The analysis does not go into detail, but gives some interesting indications: The external costs are not fully covered in the Nordic energy systems, the present taxes and charges are not high enough. The emissions from the energy systems would be strongly reduced, if taxes/environmental charges were set at the level ExternE calculate. The emissions from power production would be reduced most. Renewable energy sources and natural gas dominate the energy systems in the ExternE case

  1. Gamma Splines and Wavelets

    Directory of Open Access Journals (Sweden)

    Hannu Olkkonen

    2013-01-01

    Full Text Available In this work we introduce a new family of splines termed as gamma splines for continuous signal approximation and multiresolution analysis. The gamma splines are born by -times convolution of the exponential by itself. We study the properties of the discrete gamma splines in signal interpolation and approximation. We prove that the gamma splines obey the two-scale equation based on the polyphase decomposition. to introduce the shift invariant gamma spline wavelet transform for tree structured subscale analysis of asymmetric signal waveforms and for systems with asymmetric impulse response. Especially we consider the applications in biomedical signal analysis (EEG, ECG, and EMG. Finally, we discuss the suitability of the gamma spline signal processing in embedded VLSI environment.

  2. External costs of electricity

    International Nuclear Information System (INIS)

    Rabl, A.; Spadaro, J.V.

    2005-01-01

    This article presents a synthesis of the ExternE project (External costs of Energy) of the European community about the external costs of power generation. Pollution impacts are calculated using an 'impact pathways' analysis, i.e. an analysis of the emission - dispersion - dose-response function - cost evaluation chain. Results are presented for different fuel cycles (with several technological variants) with their confidence intervals. The environmental impact costs are particularly high for coal: for instance, in France, for coal-fired power plants it is of the same order as the electricity retail price. For natural gas, this cost is about a third of the one for coal. On the contrary, the environmental impact costs for nuclear and renewable energies are low, typically of few per cent of the electricity price. The main part of these costs corresponds to the sanitary impacts, in particular the untimely mortality. In order to avoid any controversy about the cost evaluation of mortality, the reduction of the expectation of life due to the different fuel cycles is also indicated and the risks linked with nuclear energy are presented using several comparisons. (J.S.)

  3. On parabolic external maps

    DEFF Research Database (Denmark)

    Lomonaco, Luna; Petersen, Carsten Lunde; Shen, Weixiao

    2017-01-01

    We prove that any C1+BV degree d ≥ 2 circle covering h having all periodic orbits weakly expanding, is conjugate by a C1+BV diffeomorphism to a metrically expanding map. We use this to connect the space of parabolic external maps (coming from the theory of parabolic-like maps) to metrically expan...

  4. Stochastic Control - External Models

    DEFF Research Database (Denmark)

    Poulsen, Niels Kjølstad

    2005-01-01

    This note is devoted to control of stochastic systems described in discrete time. We are concerned with external descriptions or transfer function model, where we have a dynamic model for the input output relation only (i.e.. no direct internal information). The methods are based on LTI systems...

  5. Gamma-ray lasing by free nuclei and by matter-antimatter beams

    International Nuclear Information System (INIS)

    Rivlin, L.A.

    1997-01-01

    I discuss the possibilities to induce the gamma-ray emission departing from attempts to use the Moessbauer effect. Three separate approaches are considered: (A) Stimulated radiative transitions in deeply cooled nuclear beams with hidden inversion; (B) external two-photon ignition of nuclear lasing accompanied by gamma-ray giant pulse emission; and (C) burst-like radiative annihilation of relativistic beams of electrons and positrons or parapositronium atoms ignited by an external beam of soft photons

  6. Gamma-ray imaging probes

    International Nuclear Information System (INIS)

    Wild, W.J.

    1988-01-01

    External nuclear medicine diagnostic imaging of early primary and metastatic lung cancer tumors is difficult due to the poor sensitivity and resolution of existing gamma cameras. Nonimaging counting detectors used for internal tumor detection give ambiguous results because distant background variations are difficult to discriminate from neighboring tumor sites. This suggests that an internal imaging nuclear medicine probe, particularly an esophageal probe, may be advantageously used to detect small tumors because of the ability to discriminate against background variations and the capability to get close to sites neighboring the esophagus. The design, theory of operation, preliminary bench tests, characterization of noise behavior and optimization of such an imaging probe is the central theme of this work

  7. Gamma ray astronomy

    International Nuclear Information System (INIS)

    Fichtel, C.E.

    1975-01-01

    The first certain detection of celestial high energy gamma rays came from a satellite experiment flown on the third Orbiting Solar Observatory (OSO-111). A Gamma ray spark chamber telescope with substantively greater sensitivity and angular resolution (a few degrees) flown on the second Small Astronomy Satellite (SAS-II) has now provided a better picture of the gamma ray sky, and particularly the galactic plane and pulsars. This paper will summarize the present picture of gamma ray astronomy as it has developed at this conference from measurements made with experiments carried out on balloons, those remaining on the ground, and ones flown on satellites. (orig.) [de

  8. The determination of the thermal neutron and gamma fluxes at the Maryland University Training Reactor using thermoluminescent dosimetry

    International Nuclear Information System (INIS)

    Karceski, Jeffrey David; Ebert, David D.; Munno, Frank J.

    1988-01-01

    Determination of the dose received by a material in a mixed gamma and neutron field is of paramount concern to any research reactor owner. This dose can be separated into three distinguishable parts using standard thermoluminescent dosimetry (TLD) responses: 1) thermal neutron dose, 2) fission gamma dose, and 3) fission product gamma dose. For the Maryland University Training Reactor (MUTR), these respective fluences were determined for each of the associated experimental facilities. Quantifying the magnitude of the gamma and thermal neutron exposures at various reactor power levels was accomplished using Li-6F and Li-7F TLDs, respectively. These two types of dosimetry were chosen given the following considerations: 1) there is no existing standard established for fluence determination in a mixed field, 2) the LiF TLDs have a wide range of sensitivity to radiation, from 0.01 mR to 10,000 R, and 3) LiF TLDs are easy to read given the proper equipment. Standardization of the gamma/neutron doses was accomplished using the 500,000 Rad/hr Co-60 gamma source also located at the University of Maryland. (author)

  9. ExternE transport methodology for external cost evaluation of air pollution

    DEFF Research Database (Denmark)

    Jensen, S. S.; Berkowicz, R.; Brandt, J.

    The report describes how the human exposure estimates based on NERI's human exposure modelling system (AirGIS) can improve the Danish data used for exposure factors in the ExternE Transport methodology. Initially, a brief description of the ExternE Tranport methodology is given and it is summarised...

  10. Pulser injection with subsequent removal for gamma-ray spectrometry

    International Nuclear Information System (INIS)

    Hartwell, J.K.; Goodwin, S.G.; Johnson, L.O.; Killian, E.W.

    1990-01-01

    This patent describes a module for use with a gamma-ray spectroscopy system. The system includes a gamma-ray detector for detecting gamma-ray events and producing a signal representing the gamma-ray events, a converter responsive to the detector and capable of converting the signal to a spectrum, a storage memory responsive to the converter and capable of storing the spectrum at address locations in memory, and a pulser capable of injecting pulses into the signal produced by the detector. The module comprises: means for generating a logic pulse for controlling the pulser, the controlling means adapted for coupling to the pulser; means for generating separation of events logic to isolate the components of a combined gamma-ray---pulse spectrum, the separation of events logic means adapted for coupling to the converter and the storage memory with the capability of storing pulses at address locations in the storage memory separate from the gamma-ray events; means for receiving an imitating signal from the converter to generate a plurality of operations by the module; means for tracking variations in a gamma-ray---pulse spectrum brought on by external parameter changes; and means for interfacing with commercially developed gamma-ray spectrometry equipment

  11. Checklists for external validity

    DEFF Research Database (Denmark)

    Dyrvig, Anne-Kirstine; Kidholm, Kristian; Gerke, Oke

    2014-01-01

    to an implementation setting. In this paper, currently available checklists on external validity are identified, assessed and used as a basis for proposing a new improved instrument. METHOD: A systematic literature review was carried out in Pubmed, Embase and Cinahl on English-language papers without time restrictions....... The retrieved checklist items were assessed for (i) the methodology used in primary literature, justifying inclusion of each item; and (ii) the number of times each item appeared in checklists. RESULTS: Fifteen papers were identified, presenting a total of 21 checklists for external validity, yielding a total...... of 38 checklist items. Empirical support was considered the most valid methodology for item inclusion. Assessment of methodological justification showed that none of the items were supported empirically. Other kinds of literature justified the inclusion of 22 of the items, and 17 items were included...

  12. Gamma tomography apparatus

    International Nuclear Information System (INIS)

    Span, F.J.

    1988-01-01

    The patent concerns a gamma tomography apparatus for medical diagnosis. The apparatus comprises a gamma scintillation camera head and a suspension system for supporting and positioning the camera head with respect for the patient. Both total body scanning and single photon emission tomography can be carried out with the apparatus. (U.K.)

  13. Gamma-sterilization

    International Nuclear Information System (INIS)

    Lindgren, E.

    1974-01-01

    The author makes a survey of his experience in sterilization and sterility control of medical products. At present three different methods are used, steamsterilization, gassterilizing and gammasterilizing. The investments and costs for gamma radiation is presented and a comparison of the costs for gamma- and gassterilization including sterility control is made. (M.S.)

  14. Gamma-ray sources

    International Nuclear Information System (INIS)

    Hermsen, W.

    1980-01-01

    Results are presented from an analysis of the celestial gamma-ray fine-scale structure based on over half of the data which may ultimately be available from the COS-B satellite. A catalogue consisting of 25 gamma-ray sources measured at energies above 100 MeV is presented. (Auth.)

  15. Gamma ray astronomy

    International Nuclear Information System (INIS)

    Hillier, R.

    1984-01-01

    The book reviews the development of gamma ray astronomy over the past twenty five years. A large section of the book is devoted to the problems of background radiation and the design of detectors. Gamma rays from the sun, the galactic disc, the galaxy, and extra galactic sources; are also discussed. (U.K.)

  16. Effects of Gamma Irradiation on Ruminal Degradation of Samurai 1 Sweet Sorghum Bagasse

    Directory of Open Access Journals (Sweden)

    T. Wahyono

    2017-06-01

    Full Text Available The purpose of this study was to investigate the influence of gamma irradiation on dry matter, organic matter, and neutral detergent fiber degradability of Samurai 1 sweet sorghum bagasse, to facilitate its utilization in ruminant diets. Sorghum bagasse was obtained from Samurai 1 sorghum stem by-product after juice extraction. Gamma irradiation was carried out in a cobalt-60 irradiator in the Center for the Application of Isotopes and Radiation. Two polyethylene packages of samples were irradiated in gamma cell (Co-60 at doses of 50 and 100 kGy in the presence of air. Treatments were untreated/unirradiated and  50- and 100-kGy gamma irradiation. Sample were incubated in the rumen for periods of 0, 8, 24, 48, and 72 h with in sacco method. The observed parameters were the degradations of dry matter (DM, organic matter (OM, and neutral detergent fiber (NDF. DM, OM and NDF degradation characteristics were also observed. DM degradation of 50 kGy irradiation dose started higher than untreated samples after 24 hours incubation while OM degradation started higher than untreated samples after 48 hours incubation. DM and OM degradation of 100 kGy irradiation started higher than untreated after 8 hours incubation. Gamma irradiation treatment of 50 kGy and 100 kGy could increase NDF degradation on 8 to 72 hours incubation. Irradiation was also capable to increase NDF degradation rate (c fraction and ruminal effective degradation (ED value on Samurai 1 sweet sorghum bagasse. Gamma Irradiation could break down the lignocellulose materials, break β 1,4 branch chain of cellulose and make it easily digested for rumen bacteria. The best dose of gamma irradiation for processing Samurai 1 sweet sorghum bagasse as a fiber source for ruminants was 100 kGy.Received: 10 December 2015; Revised: 10 October 2016; Accepted: 10 October 2016

  17. MCNP simulation of the influence of the external moisture on low calorific value in the coal quality analysis by neutron

    International Nuclear Information System (INIS)

    Liu Dekun; Zhang Hongyu; Zhang Lihong; Dong Huan; Gu Deshan

    2012-01-01

    An important index in assessment of coal quality is low calorific value. Using neutron to analysis coal quality, the more the coal moisture content, especially the increasing of external moisture will reduce the low calorific value. The principle of coal quality analysis by neutron prompt Gamma-ray is introduced. The influence of the gamma count of the carbon element peak with increasing external moisture in coal samples was simulated using MCNP code. And discussed the reasons how external moisture content influence the calorific value. Simulation results indicate that with the increasing of external moisture in the coal samples, the gamma count of the carbon element peak dwindling, and the low calorific value reducing. The conclusion is : using neutrons method to analysis coal quality, the more external moisture content, the larger error of the measurement results of the carbon element, and will influence the calculation accuracy of the low calorific value. (authors)

  18. Influence of gamma radiation on the colour strength and fastness properties of fabric using turmeric (Curcuma longa L.) as natural dye

    International Nuclear Information System (INIS)

    Bhatti, Ijaz A.; Adeel, Shahid; Jamal, M. Asghar; Safdar, Muhammad; Abbas, Muhammad

    2010-01-01

    The effect of gamma radiation on the dyeing of cotton with extract of turmeric (Curcuma longa L.) powder has been investigated. Cotton fabric and turmeric powder were irradiated to absorbed doses of 1, 2, 3, 4 and 6 kGy using Co-60 gamma irradiator. Dyeing parameters such as temperature, pH and mordant concentration were optimized. Dyeing was performed using un-irradiated and irradiated cotton with the extracts of un-irradiated and irradiated turmeric powder in order to investigate the effect of radiation treatment on the colour strength of dyed fabric. The reported data of un-irradiated and irradiated fabrics dyed with un-irradiated and irradiated dyes were obtained using the spectraflash SF-650. The colourfastness to light, rubbing- and washing-fastness properties showed that gamma irradiation has improved the dyeing characteristics from fair to good.

  19. Influence of gamma radiation on the colour strength and fastness properties of fabric using turmeric (Curcuma longa L .) as natural dye

    Science.gov (United States)

    Bhatti, Ijaz A.; Adeel, Shahid; Jamal, M. Asghar; Safdar, Muhammad; Abbas, Muhammad

    2010-05-01

    The effect of gamma radiation on the dyeing of cotton with extract of turmeric ( Curcuma longa L.) powder has been investigated. Cotton fabric and turmeric powder were irradiated to absorbed doses of 1, 2, 3, 4 and 6 kGy using Co-60 gamma irradiator. Dyeing parameters such as temperature, pH and mordant concentration were optimized. Dyeing was performed using un-irradiated and irradiated cotton with the extracts of un-irradiated and irradiated turmeric powder in order to investigate the effect of radiation treatment on the colour strength of dyed fabric. The reported data of un-irradiated and irradiated fabrics dyed with un-irradiated and irradiated dyes were obtained using the spectraflash SF-650. The colourfastness to light, rubbing- and washing-fastness properties showed that gamma irradiation has improved the dyeing characteristics from fair to good.

  20. Influence of gamma radiation on the colour strength and fastness properties of fabric using turmeric (Curcuma longa L.) as natural dye

    Energy Technology Data Exchange (ETDEWEB)

    Bhatti, Ijaz A., E-mail: ijazchem@yahoo.co [Department of Chemistry, University of Agriculture, Faisalabad 38040 (Pakistan); Adeel, Shahid [Department of Chemistry, University of Agriculture, Faisalabad 38040 (Pakistan); Jamal, M. Asghar [Department of Chemistry, G.C. University, Faisalabad 38040 (Pakistan); Safdar, Muhammad [Department of Chemistry, University of A J and K, Muzaffarabad, Azad Kashmir (Pakistan); Abbas, Muhammad [Haris Dyes and Chemicals, Faisalabad 38040 (Pakistan)

    2010-05-15

    The effect of gamma radiation on the dyeing of cotton with extract of turmeric (Curcuma longa L.) powder has been investigated. Cotton fabric and turmeric powder were irradiated to absorbed doses of 1, 2, 3, 4 and 6 kGy using Co-60 gamma irradiator. Dyeing parameters such as temperature, pH and mordant concentration were optimized. Dyeing was performed using un-irradiated and irradiated cotton with the extracts of un-irradiated and irradiated turmeric powder in order to investigate the effect of radiation treatment on the colour strength of dyed fabric. The reported data of un-irradiated and irradiated fabrics dyed with un-irradiated and irradiated dyes were obtained using the spectraflash SF-650. The colourfastness to light, rubbing- and washing-fastness properties showed that gamma irradiation has improved the dyeing characteristics from fair to good.

  1. Structure and content of the galaxy and galactic gamma rays

    International Nuclear Information System (INIS)

    1976-01-01

    The conference included papers on γ-ray pulsars, galactic diffuse flux and surveys, radio surveys of external galaxies, galactic distribution of pulsars, and galactic gamma emission. Galactic structure drawing on all branches of galactic astronomy is discussed. New and unpublished material is included

  2. Mount makes liquid nitrogen-cooled gamma ray detector portable

    Science.gov (United States)

    Fessler, T. E.

    1966-01-01

    Liquid nitrogen-cooled gamma ray detector system is made portable by attaching the detector to a fixture which provides a good thermal conductive path between the detector and the liquid nitrogen in a dewar flask and a low heat leak path between the detector and the external environment.

  3. Disinfection of Water and Wastewater Using Gamma Irradiation in Isfahan Water and Wastewater Treatment Plants

    Directory of Open Access Journals (Sweden)

    Hassan Hashemi

    2011-01-01

    Full Text Available To investigate the effect of gamma irradiation on the disinfection of water and wastewater, water samples were collected from raw and filtered water and wastewater samples were taken from the effluent of the secondary sedimentation, polished effluent (1-day retention time, and also from filtered (rapid sand filter effluent. The samples were irradiated with gamma collimated beam in a batch system using a Co-60 therapeutic gamma radiation machine with a radioactive source emission rate of 405.38CGy/min at different doses of 20-160 Gy and 80-240 Gy, respectively. The samples were analyzed before and after irradiation for total and fecal coliforms. It was observed that nearly 100% reduction was achieved in total and fecal coliforms in water samples treated with a dose of 160 Gy. Depending on effluent quality, disinfection efficiencies achieved using 240 Gy gamma irradiation for inactivation of total coliforms in wastewater samples were 83, 64, and 56 percent for filtered, clarified, and secondary effluents, respectively. The same values were nearly 81, 58, and 46 percent, respectively, for inactivation of fecal coliforms. At lower doses of 120-240Gy, the coliform bacteria were successfully inactivated. It was concluded that a linear correlation holds between the dose delivered and the inactivation of microorganisms, so that inactivation increases with increasing irradiation time.

  4. Influence of gamma radiation on secondary metabolism in lichens Cladonia substellata and Cladonia verticillaris

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Helena P.B.; Melo, Patryk; Primo, Dario; Vicalvi, Maria Claudia V. [Federal University of Pernambuco (CTG/DEN/UFPE), Recife, PE (Brazil). Graduate Program in Energy Technologies and Nuclear; Maciel, Leonardo N.Q. [First Space Seed, Recife, PE (Brazil); Pereira, Eugenia, E-mail: Eugenia.pereira@cnpq.pq.com.b [Federal University of Pernambuco (CFCH/UFPE), Recife, PE (Brazil). Dept. of Geographic Sciences; Silva, Nicacio [Federal University of Pernambuco (CCB/UFPE), Recife, PE (Brazil). Dept. of Biochemistry; Colaco, Waldeciro, E-mail: wcolaco@ufpe.com.b [Federal University of Pernambuco (CTG/DEN/UFPE), Recife, PE (Brazil). Dept. Nuclear Energy

    2011-07-01

    Lichens are organisms formed from a symbiotic relationship between a fungus and an alga. These when submitted to different doses and types of radiation are encouraged to produce their substances in quantities different from those that would produce without the intervention of radiation. The objective of this research was to determine the influence of gamma rays on the production of usnic acid from Cladonia substellata and on the production of fumarprocetraric acid from Cladonia verticillaris. Lichens samples were submitted to gamma irradiation Co-60 source, receiving different doses (0, 5, 10, 50 and 100 Gy) of gamma irradiator. After six months samples were collected and submitted to the extraction of its phenols. The extracts were subjected to thin-layer chromatography, and read from Biochrom Libra S22 spectrophotometer. The qualitative assessment of the chemical composition of lichens stalks irradiated or not, revealed by thin layer chromatography production of usnic acid and fumarprocetraric throughout the experiment. Regarding the quantification of fumarprocetraric acid was observed a production significantly higher in extracts obtained from irradiated lichens, the largest production obtained by the dose of 50 Gy. As for the production of usnic acid, the highlight was the dose of 10 Gy. Thus we can conclude that the lichens Cladonia verticillaris and Cladonia substellata when submitted to gamma radiation in the laboratory, produce fumarprocetraric acid and usnic acid , respectively, but the radiation dose influences the metabolism and its subsequent biosynthesis. (author)

  5. The influence of gamma irradiation on natural dyeing properties of cotton and flax fabrics

    Science.gov (United States)

    Chirila, Laura; Popescu, Alina; Cutrubinis, Mihalis; Stanculescu, Ioana; Moise, Valentin Ioan

    2018-04-01

    Fabrics made of 100% cotton and 100% flax respectively were exposed at ambient temperature to gamma radiation doses, from 5 to 40 kGy, using a Co-60 research irradiator. After the irradiation treatment the fabrics were subjected to dyeing process with Itodye Nat Pomegranate commercial natural dye. The influence of gamma irradiation treatment on the physical-mechanical properties, dyeing and surface morphology of natural fibres were investigated. Gamma ray treatment of 40 kGy was the most effective in the case of fabrics made from 100% cotton, enhancing the colour strength as evidenced by K/S value. The results obtained from the mechanical properties of fabrics made of 100% flax indicated that the dose of 40 kGy leads to a decrease of tensile strength up of to 41.5%. Infrared spectroscopy was used to monitor chemical and structural changes in cellulosic fibres induced during processing. Crystallinity indices calculated from various bands ratio showed insignificant variations for cotton and small variations in the case of flax. The surface morphology of irradiated cotton fabrics did not show significant changes even at the highest dose of 40 kGy, while the low doses applied on flax fabrics led to an appearance of small changes of surface morphology. The gamma irradiation increased the uptake of natural dyes on natural cellulosic fibres.

  6. Influence of gamma radiation on secondary metabolism in lichens Cladonia substellata and Cladonia verticillaris

    International Nuclear Information System (INIS)

    Silva, Helena P.B.; Melo, Patryk; Primo, Dario; Vicalvi, Maria Claudia V.; Pereira, Eugenia; Silva, Nicacio; Colaco, Waldeciro

    2011-01-01

    Lichens are organisms formed from a symbiotic relationship between a fungus and an alga. These when submitted to different doses and types of radiation are encouraged to produce their substances in quantities different from those that would produce without the intervention of radiation. The objective of this research was to determine the influence of gamma rays on the production of usnic acid from Cladonia substellata and on the production of fumarprocetraric acid from Cladonia verticillaris. Lichens samples were submitted to gamma irradiation Co-60 source, receiving different doses (0, 5, 10, 50 and 100 Gy) of gamma irradiator. After six months samples were collected and submitted to the extraction of its phenols. The extracts were subjected to thin-layer chromatography, and read from Biochrom Libra S22 spectrophotometer. The qualitative assessment of the chemical composition of lichens stalks irradiated or not, revealed by thin layer chromatography production of usnic acid and fumarprocetraric throughout the experiment. Regarding the quantification of fumarprocetraric acid was observed a production significantly higher in extracts obtained from irradiated lichens, the largest production obtained by the dose of 50 Gy. As for the production of usnic acid, the highlight was the dose of 10 Gy. Thus we can conclude that the lichens Cladonia verticillaris and Cladonia substellata when submitted to gamma radiation in the laboratory, produce fumarprocetraric acid and usnic acid , respectively, but the radiation dose influences the metabolism and its subsequent biosynthesis. (author)

  7. External dose estimates for future Bikini Atoll inhabitants

    International Nuclear Information System (INIS)

    Gudiksen, P.H.; Crites, T.R.; Robison, W.L.

    1976-01-01

    To evaluate the potential radiation doses that may be received by the returning Bikinians, we surveyed the residual radioactivity on Bikini and Eneu Islands in June of 1975. An integral part of the survey included measurements of gamma-ray exposure rates which are used to estimate external gamma-ray doses. The survey showed that on Bikini Island the rates are highly variable: values near the shores are generally of the order of 10 to 20 μR/h, while those within the interior average about 40 μR/h with a range of roughly 30 to 100 μR/h. Eneu Island, however, is characterized by more or less uniformly distributed gamma radiation levels of less than 10 μR/h over the entire island. These data, in conjunction with population statistics and expected life styles, allowed us to estimate the potential external gamma-ray doses associated with proposed housing locations along the lagoon road and within the interior portions of Bikini Island as well as along the lagoon side of Eneu Island. As expected, living on Eneu Island results in the lowest doses: 0.12 rem during the first year and 2.9 rem during 30 years. The highest values, 0.28 rem during the first year and 5.9 rem over 30 years, may potentially be received by inhabitants living within the interior of Bikini Island. Other options under consideration produce intermediate values

  8. Manual on self-contained gamma irradiators (categories 1 and 3). Incorporating: Applications guide, procedures guide, basics guide

    International Nuclear Information System (INIS)

    1996-01-01

    The document is the first revision of a previous one published in 1993 to provide guidance on the safe use and regulation of panoramic gamma irradiators (Co-60 or Cs-137 sources) in different fields of application. It includes three parts: Applications Guide, which describes the main applications of panoramic gamma irradiators, the type of equipment, including safety systems, operation and maintenance, and how to deal with incidents. Procedures Guide, which gives step by step instructions on how to carry out the practice. Basics Guide, which explains the fundamentals of radiation, the system of units, interaction of radiation with matter radiation detection, etc. and which is common to all documents in the series. The manual is aimed primarily at persons handling such radiation sources on a daily routine basis, as well as at the competent authorities for training of workers in radiation protection or for setting up local radiation protection rules

  9. Effect of Gamma Ray Energies and Steel Fiber addition by Weight on some Shielding Properties of Limestone Concrete

    International Nuclear Information System (INIS)

    Abd El-Latifa, A.A.; Ikraiam, F.A.; Abd El-Latifa, A.A.; Abd Elazziz, A.; Abd Elazziz, A.

    2010-01-01

    The mass attenuation coefficient , the build up factor , the half value thickness X 1/2 , and tenth value thickness X 1/10 of fiber concrete , 0% , 1% , 2%, 3%, and 4% by weight fiber content were measured at different gamma ray energies in MeV, 0.511,1.274 from Na-22 ,1.17 ,1.33 from Co-60 and 0.662 from Cs-137 . Appreciable variations were noted in the former nuclear parameters, due to the changes in the fiber content and gamma ray energies .A comparison of shielding properties of concrete with fiber content and reference sample(concrete without fiber ) have proven that the addition of steel fibers by weight to concrete have a potential application as a radiation shielding

  10. Induction of mutation on mulberry (morus alba L.) by using in vitro techniques in combination with gamma irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Nguyen Van Vinh [Nuclear Research Institute, Department of Biotechnology, Dalat (Viet Nam)

    2001-03-01

    Mutation induction and selection of desired characters on mulberry will contribute to industrialization and modernization in agricultural development in Vietnam. The objectives are to conduct biochemical and physiological analyses of collected mulberry varieties and to improve techniques for boosting yield and better quality in some mulberry genotypes by using in vitro technique combined with gamma irradiation. Two mulberry varieties named BauDen and VA 186 were used. Cuts of them were treated with gamma rays of Co-60, cultivated in experimental field with use of vitro technique to rapidly isolate mutants in irradiated population and investigated for plantlets, color of leaves, etc 30 days after cultivation. The results on the mutation frequency and spectrum of variation as well as the results of selection and isolation are presented. Eleven mutated clones from the two starting varieties were obtained during 1993-99. Three of them are now being cultivated in LamDong province fields. (S. Ohno)

  11. Induction of mutation on mulberry (morus alba L.) by using in vitro techniques in combination with gamma irradiation

    International Nuclear Information System (INIS)

    Nguyen Van Vinh

    2001-01-01

    Mutation induction and selection of desired characters on mulberry will contribute to industrialization and modernization in agricultural development in Vietnam. The objectives are to conduct biochemical and physiological analyses of collected mulberry varieties and to improve techniques for boosting yield and better quality in some mulberry genotypes by using in vitro technique combined with gamma irradiation. Two mulberry varieties named BauDen and VA 186 were used. Cuts of them were treated with gamma rays of Co-60, cultivated in experimental field with use of vitro technique to rapidly isolate mutants in irradiated population and investigated for plantlets, color of leaves, etc 30 days after cultivation. The results on the mutation frequency and spectrum of variation as well as the results of selection and isolation are presented. Eleven mutated clones from the two starting varieties were obtained during 1993-99. Three of them are now being cultivated in LamDong province fields. (S. Ohno)

  12. Comparison and limitations of three different bulk etch rate measurement methods used for gamma irradiated PM-355 detectors

    Energy Technology Data Exchange (ETDEWEB)

    Fazal-ur-Rehman E-mail: fazalr@kfupm.edu.sa; Abu-Jarad, F.; Al-Jarallah, M.I.; Farhat, M

    2001-06-01

    Samples of Nuclear Track Detectors (PM-355) were exposed to high gamma doses from 1x10{sup 5} Gy (10 Mrad) up to 1.2x10{sup 6} Gy (120 Mrad) at an incremental dose of 1x10{sup 5} Gy (10 Mrad). The gamma source was a 9.03 PBq (244 kCi) Co-60 source used for sterilization of medical syringes. The bulk etch rate (V{sub b}) was measured for various high gamma doses by three different methods: 1--thickness change method; 2--mass change method; 3--fission track diametric method. The study gives a comparison and limitations of these three methods used for bulk etch rate measurements in the detectors as a function of high gamma doses. The track etch rate (V{sub t}) and the sensitivity (V) of the detector were also measured using the fission track diametric method. It was observed that V{sub b} increases with the increase of the gamma absorbed dose at a fixed etching time in each bulk etch measuring method. The bulk etch rate decreases exponentially with the etching time at a fixed gamma absorbed dose in all three methods. The thickness change and mass change methods have successfully been applied to measure V{sub b} at higher gamma doses up to 1.2x10{sup 6} Gy (120 Mrad). The bulk etch rate determined by the mass change and thickness change methods was almost the same at a certain gamma dose and etching time whereas it was quite low in the case of the fission track diametric method due to its limitations at higher doses. Also in this method it was not possible to measure the fission fragment track diameters at higher doses due to the quick disappearance of the fission tracks and therefore the V{sub b} could not be estimated at higher gamma doses.

  13. Studies on Development of Polymeric Materials Using Gamma Irradiation for Contact and Intraocular Lenses

    Directory of Open Access Journals (Sweden)

    Pranshu Chhabra

    2009-01-01

    Full Text Available For the development of materials for contact lenses and intraocular lenses, the selection criteria is based on the (i capacity to absorb and retain water, (ii hydrophilicity and hydrophobicity, (iii refractive index and (iv hardness besides the other essential properties. Various monomers are being studied to develop suitable materials for such applications. Selection of suitable monomers that can be converted into optical materials of desired characteristics is the most essential step. In the present paper, an attempt has been made to develop suitable optical polymers based on 2-hydroxy ethyl methacrylate (HEMA, N-vinyl pyrrolidone (NVP, methyl methacrylate (MMA, methacrylic acid (MAA, and styrene. Compositions were prepared in such a way that polymers of varying hydrophilicity or hydrophobicity could be obtained keeping HEMA as the base (main monomer. For polymerization, gamma irradiation (Co-60 as a source was used. The results of the study showed that: (i an increase in NVP and MAA content brought in an increase in hydrophilicity of polymerized HEMA (pHEMA, while the addition of styrene and MMA decreased hydrophilicity of polymerized HEMA (pHEMA, (ii polymers for contact lenses with water retention capacity as high as >50 wt.% and as low as <10 wt% with varying content of suitable comonomers can be designed, (iii polymeric materials for contact lenses can be made by using radiation processing such as Co-60 and (iv a dose of 40 kGy was found to be ideal for purpose.

  14. A high rate gamma spectroscopy system for activation analysis of short lived isomeric transitions

    Energy Technology Data Exchange (ETDEWEB)

    Westphal, G P [Atominstitut, Vienna (Austria)

    1976-07-01

    A high rate spectroscopy system specially suited for measurement of short-lived isomeric transitions is described, which, as part of a fast activation analysis facility at the TRIGA Mark II reactor, provides for automatic recording and immediate evaluation of gamma spectra taken from nuclides activated at stationary or pulsed reactor power. The system consists of a commercial DC-coupled Ge(Li)-detector of 70 cm{sup 3} modified for recycling operation for input rates in excess of 500,000 c/s Co-60, a time variant trapezoidal shaping section and a fast constant dead-time ADC coupled to a programmed multi-channel analyzer. Novel circuits for efficient pile-up rejection and time variant base line restoration extend the concept of gated integration up to count rates of more than 300,000 c/s Co-60. Time-sequenced recording of spectra is performed by a mini computer operated as a front-end processor of a larger laboratory computer, where final data processing takes place. New concepts for very simple and cost-effective implementation of multi-channel analyzers by means of general purpose small computers are described. (author)

  15. Polyclonal antibody to ovomucoid determination in gamma irradiated laying eggs

    International Nuclear Information System (INIS)

    Harder, Marcia N.C.; Arthur, Valter; Silva, Lucia C.A.S.; Lopes, Tatiana G.G.; Duarte, Keila M.R.; Canniatti-Brazaca, Solange G.; Savino, Vicente J.M.; Coelho, Antonio A.D.

    2009-01-01

    To determine allergenic food proteins, one of the most used tests is the immunoassays such as ELISA (enzyme linked immunosorbent assay), where the antibody recognizes the antigen and this connection is showed by an enzymatic system, in other words, optical density. The aim of this study was to determine the polyclonal antibody efficiency, produced in laboratory, to identify the presence the ovomucoid antigen in treated eggs by gamma irradiation for its inactivation. To evaluate the treatments, polyclonal antibody was produced in female rabbits immunized with bioconjugated ovomucoid. Was used Freund Complete Adjuvant at first immunization and PBS Buffer at four subsequently immunizations every fifteen days, plus a booster 48 hours before the blood retreated. The blood serum was tittered by PTA-ELISA (Plate trapped antigen). All procedures were according to European Norms for ethical and animal welfare. It was used, in nature, commercial laying eggs. So the samples were submitted to the gamma radiation coming from a source of Co 60 , type Multipurpose, under a dose rate of 19.4 and 31.8 Gy/hour, in the doses: 0 (control); 10 KGy; 20 KGy and 30 KGy, in all rates. By the ELISA.s test we can find the egg allergen ovomucoid and the radiation treatment do not showed considerable changes. So we can concluded that the antibody produced is capable of identify the ovomucoid allergenic protein and the gamma irradiation in such rates does not shows changes in that protein, therefore showed some changes in the color and visual viscosity of the egg samples. (author)

  16. Implementation of a system for external audits beam radiation therapy in terms of reference no

    International Nuclear Information System (INIS)

    Alonso Samper, Jose Luis; Dominguez, Lourdes; Alert Silva, Jose; Alfonso Laguardia, Rodolfo; Larrinaga Cortina, Eduardo; Garcia Yip, Fernando; Rodriguez Machado, Jorge; Morales Lopez, Jorge Luis; Silvestre Patallo, Ileana

    2009-01-01

    This paper presents our experience in implementing a external audit system for radiotherapy beam in no reference conditions with the use of CIRS and a summary of the measurements with him made.This paper presents our experience in implementing a external audit system for radiotherapy beam in no reference conditions with the use of CIRS and a summary of the measurements with him made. Centers were audited with external beam high-energy Co-60, 6 MV and 15 MV and were considered 4 treatment planning systems (TPS): AMEPLAN, Theraplan Plus, Precise Plan and MIRS to calculate doses prescribed in each test case. All measurements were acquired by the audit team using the anthropomorphic phantom CIRS, Semiflex chamber PTW 31010 and PTW electrometer STATES. The implementation and development of the external audits of beams radiotherapy in terms of 'no reference' has brought an improvement in both clinical aspects of treatment and the radiation safety and the quality control, has given us greater confidence and for this reason we believe has become essential. (Author)

  17. GammaWorkshops Proceedings

    Energy Technology Data Exchange (ETDEWEB)

    Ramebaeck, H. (ed.) (Swedish Defence Research Agency (Sweden)); Straalberg, E. (Institute for Energy Technology, Kjeller (Norway)); Klemola, S. (Radiation and Nuclear Safety Authority, STUK (Finland)); Nielsen, Sven P. (Technical Univ. of Denmark. Risoe National Lab. for Sustainable Energy, Roskilde (Denmark)); Palsson, S.E. (Icelandic Radiation Safety Authority (Iceland))

    2012-01-15

    Due to a sparse interaction during the last years between practioners in gamma ray spectrometry in the Nordic countries, a NKS activity was started in 2009. This GammaSem was focused on seminars relevant to gamma spectrometry. A follow up seminar was held in 2010. As an outcome of these activities it was suggested that the 2011 meeting should be focused on practical issues, e.g. different corrections needed in gamma spectrometric measurements. This three day's meeting, GammaWorkshops, was held in September at Risoe-DTU. Experts on different topics relevant for gamma spectrometric measurements were invited to the GammaWorkshops. The topics included efficiency transfer, true coincidence summing corrections, self-attenuation corrections, measurement of natural radionuclides (natural decay series), combined measurement uncertainty calculations, and detection limits. These topics covered both lectures and practical sessions. The practical sessions included demonstrations of tools for e.g. corrections and calculations of the above meantioned topics. (Author)

  18. Environmental external effects from wind power based on the EU ExternE methodology

    DEFF Research Database (Denmark)

    Ibsen, Liselotte Schleisner; Nielsen, Per Sieverts

    1998-01-01

    of the Danish part of the project is to implement the framework for externality evaluation, for three different power plants located in Denmark. The paper will focus on the assessment of the impacts of the whole fuel cycles for wind, natural gas and biogas. Priority areas for environmental impact assessment......The European Commission has launched a major study project, ExternE, to develop a methodology to quantify externalities. A “National Implementation Phase”, was started under the Joule II programme with the purpose of implementing the ExternE methodology in all member states. The main objective...

  19. The gamma function

    CERN Document Server

    Artin, Emil

    2015-01-01

    This brief monograph on the gamma function was designed by the author to fill what he perceived as a gap in the literature of mathematics, which often treated the gamma function in a manner he described as both sketchy and overly complicated. Author Emil Artin, one of the twentieth century's leading mathematicians, wrote in his Preface to this book, ""I feel that this monograph will help to show that the gamma function can be thought of as one of the elementary functions, and that all of its basic properties can be established using elementary methods of the calculus."" Generations of teachers

  20. External corners as heat bridges

    Energy Technology Data Exchange (ETDEWEB)

    Berber, J.

    1984-08-01

    The maximum additional heat loss in vertical external corners depending on wall thickness is determined. In order to amire at a low k-value, a much smaller wall thickness is required in externally insulated walls than in monolithic constructions; the greater loss of heat bridge with external insulation stands in contrast to a higher loss in thick, monolithic walls. In relation to total losses, the additional losses through external corners are practically negligible.

  1. [External pancreatic fistulas management].

    Science.gov (United States)

    Stepan, E V; Ermolov, A S; Rogal', M L; Teterin, Yu S

    The main principles of treatment of external postoperative pancreatic fistulas are viewed in the article. Pancreatic trauma was the reason of pancreatic fistula in 38.7% of the cases, operations because of acute pancreatitis - in 25.8%, and pancreatic pseudocyst drainage - in 35.5%. 93 patients recovered after the treatment. Complex conservative treatment of EPF allowed to close fistulas in 74.2% of the patients with normal patency of the main pancreatic duct (MPD). The usage of octreotide 600-900 mcg daily for at least 5 days to decrease pancreatic secretion was an important part of the conservative treatment. Endoscopic papillotomy was performed in patients with major duodenal papilla obstruction and interruption of transporting of pancreatic secretion to duodenum. Stent of the main pancreatic duct was indicated in patients with extended pancreatic duct stenosis to normalize transport of pancreatic secretion to duodenum. Surgical formation of anastomosis between distal part of the main pancreatic duct and gastro-intestinal tract was carried out when it was impossible to fulfill endoscopic stenting of pancreatic duct either because of its interruption and diastasis between its ends, or in the cases of unsuccessful conservative treatment of external pancreatic fistula caused by drainage of pseudocyst.

  2. External exposure from radionuclides in soil: analytical vs. simulation procedures

    International Nuclear Information System (INIS)

    Velasco, Hugo; Rizzotto, Marcos

    2008-01-01

    Full text: The external gamma irradiation resulting from radionuclides deposited on the ground surface can be an important source of radiation exposure. The assessment of this irradiation is extremely complex due to the large number of environmental factors which affect the gamma photon flux in air originating from the ground. The source energy affects the interaction between the radiation and the medium, and the characteristics and the properties of the soil are the most relevant factors to determine the energy and the angular distribution of gamma radiation in air 1 m above the ground surface. From an analytical point of view the calculations are based on the point-kernel integration method and assume that the source concentration at any depth in soil is uniform over an infinite surface parallel to the ground plane. The dose-rate factor is applied to environmental dose assessments by means of the general equation: H(t)= χ (t) x DRF where H is the external dose rate at time t, χ is the source concentration at the location of the exposed individual, and DRF is the dose-rate factor. Dose-rate factors in air at a height of 1 m above ground are tabulated for discrete photon energies between 0.01 and 10 MeV and for source depths in soil between 0 and 300 cm. These factors were determined for sources distributed in a slab of finite thickness and sources which are exponentially distributed with depth. A Monte Carlo algorithm was developed to simulate the gamma photons transport calculation for the soil/air configuration. In this case the soil constituents were assumed to be similar to those on the earth's crust. The model considers the gamma photons source distributed uniformly in the soil profile, from the ground surface to a depth beyond which the soil is considered uncontaminated. Source gamma photons were randomly selected from the contaminated soil zone and their subsequent interactions determined by the probability of occurrence via photoelectric effect, Compton

  3. Basics of Gamma Ray Detection

    Energy Technology Data Exchange (ETDEWEB)

    Stinnett, Jacob [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Venkataraman, Ram [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2017-09-13

    The objective of this training is to explain the origin of x-rays and gamma rays, gamma ray interactions with matter, detectors and electronics used in gamma ray-spectrometry, and features of a gamma-ray spectrum for nuclear material that is safeguarded.

  4. GammaWorkshops Proceedings

    DEFF Research Database (Denmark)

    Strålberg, Elisabeth; Klemola, Seppo; Nielsen, Sven Poul

    to the GammaWorkshops. The topics included efficiency transfer, true coincidence summing corrections, self-attenuation corrections, measurement of natural radionuclides (natural decay series), combined measurement uncertainty calculations, and detection limits. These topics covered both lectures and practical...

  5. FTR europia gamma heating

    International Nuclear Information System (INIS)

    Ward, J.T. Jr.

    1975-01-01

    Calculated and experimental gamma heating rates of europia in the Engineering Mockup Critical Assembly (EMC) were correlated. A calculated to experimental (C/E) ratio of 1.086 was established in validating the theoretical approach and computational technique applied in the calculations. Gamma heat deposition rates in the FTR with Eu 2 O 3 control absorbers were determined from three-dimensional calculations. Maximum gamma heating was found to occur near the tip of a half-inserted row 5 control rod assembly--12.8 watts/gm of europia. Gamma heating profiles were established for a single half-inserted europia absorber assembly. Local heat peaking was found not to alter significantly heating rates computed in the FTR core model, where larger mesh interval sizes precluded examination of spatially-limited heating gradients. These computations provide the basis for thermal-hydraulic analyses to ascertain temperature profiles in the FTR under europia control

  6. Beta and Gamma Gradients

    DEFF Research Database (Denmark)

    Løvborg, Leif; Gaffney, C. F.; Clark, P. A.

    1985-01-01

    Experimental and/or theoretical estimates are presented concerning, (i) attenuation within the sample of beta and gamma radiation from the soil, (ii) the gamma dose within the sample due to its own radioactivity, and (iii) the soil gamma dose in the proximity of boundaries between regions...... of differing radioactivity. It is confirmed that removal of the outer 2 mm of sample is adequate to remove influence from soil beta dose and estimates are made of the error introduced by non-removal. Other evaluations include variation of the soil gamma dose near the ground surface and it appears...... that the present practice of avoiding samples above a depth of 0.3 m may be over-cautious...

  7. Gamma spectrometry today

    International Nuclear Information System (INIS)

    Hemingway, J.

    1990-01-01

    This paper reviews the important advances in gamma spectroscopy made in recent years. Improvements in detectors and other components and the addition of on-line computer control systems is discussed. (UK)

  8. Failure modes and effects analysis (FMEA) for Gamma Knife radiosurgery.

    Science.gov (United States)

    Xu, Andy Yuanguang; Bhatnagar, Jagdish; Bednarz, Greg; Flickinger, John; Arai, Yoshio; Vacsulka, Jonet; Feng, Wenzheng; Monaco, Edward; Niranjan, Ajay; Lunsford, L Dade; Huq, M Saiful

    2017-11-01

    Gamma Knife radiosurgery is a highly precise and accurate treatment technique for treating brain diseases with low risk of serious error that nevertheless could potentially be reduced. We applied the AAPM Task Group 100 recommended failure modes and effects analysis (FMEA) tool to develop a risk-based quality management program for Gamma Knife radiosurgery. A team consisting of medical physicists, radiation oncologists, neurosurgeons, radiation safety officers, nurses, operating room technologists, and schedulers at our institution and an external physicist expert on Gamma Knife was formed for the FMEA study. A process tree and a failure mode table were created for the Gamma Knife radiosurgery procedures using the Leksell Gamma Knife Perfexion and 4C units. Three scores for the probability of occurrence (O), the severity (S), and the probability of no detection for failure mode (D) were assigned to each failure mode by 8 professionals on a scale from 1 to 10. An overall risk priority number (RPN) for each failure mode was then calculated from the averaged O, S, and D scores. The coefficient of variation for each O, S, or D score was also calculated. The failure modes identified were prioritized in terms of both the RPN scores and the severity scores. The established process tree for Gamma Knife radiosurgery consists of 10 subprocesses and 53 steps, including a subprocess for frame placement and 11 steps that are directly related to the frame-based nature of the Gamma Knife radiosurgery. Out of the 86 failure modes identified, 40 Gamma Knife specific failure modes were caused by the potential for inappropriate use of the radiosurgery head frame, the imaging fiducial boxes, the Gamma Knife helmets and plugs, the skull definition tools as well as other features of the GammaPlan treatment planning system. The other 46 failure modes are associated with the registration, imaging, image transfer, contouring processes that are common for all external beam radiation therapy

  9. Dynamic gamma knife radiosurgery

    International Nuclear Information System (INIS)

    Luan Shuang; Swanson, Nathan; Chen Zhe; Ma Lijun

    2009-01-01

    Gamma knife has been the treatment of choice for various brain tumors and functional disorders. Current gamma knife radiosurgery is planned in a 'ball-packing' approach and delivered in a 'step-and-shoot' manner, i.e. it aims to 'pack' the different sized spherical high-dose volumes (called 'shots') into a tumor volume. We have developed a dynamic scheme for gamma knife radiosurgery based on the concept of 'dose-painting' to take advantage of the new robotic patient positioning system on the latest Gamma Knife C(TM) and Perfexion(TM) units. In our scheme, the spherical high dose volume created by the gamma knife unit will be viewed as a 3D spherical 'paintbrush', and treatment planning reduces to finding the best route of this 'paintbrush' to 'paint' a 3D tumor volume. Under our dose-painting concept, gamma knife radiosurgery becomes dynamic, where the patient moves continuously under the robotic positioning system. We have implemented a fully automatic dynamic gamma knife radiosurgery treatment planning system, where the inverse planning problem is solved as a traveling salesman problem combined with constrained least-square optimizations. We have also carried out experimental studies of dynamic gamma knife radiosurgery and showed the following. (1) Dynamic gamma knife radiosurgery is ideally suited for fully automatic inverse planning, where high quality radiosurgery plans can be obtained in minutes of computation. (2) Dynamic radiosurgery plans are more conformal than step-and-shoot plans and can maintain a steep dose gradient (around 13% per mm) between the target tumor volume and the surrounding critical structures. (3) It is possible to prescribe multiple isodose lines with dynamic gamma knife radiosurgery, so that the treatment can cover the periphery of the target volume while escalating the dose for high tumor burden regions. (4) With dynamic gamma knife radiosurgery, one can obtain a family of plans representing a tradeoff between the delivery time and

  10. Dynamic gamma knife radiosurgery

    Energy Technology Data Exchange (ETDEWEB)

    Luan Shuang; Swanson, Nathan; Chen Zhe [Department of Computer Science, University of New Mexico, Albuquerque, NM 87131 (United States); Ma Lijun [Department of Radiation Oncology, University of California San Francisco, San Francisco, CA 94143 (United States)], E-mail: sluan@cs.unm.edu, E-mail: nate@cs.unm.edu, E-mail: zchen@cs.unm.edu, E-mail: lijunma@radonc.ucsf.edu

    2009-03-21

    Gamma knife has been the treatment of choice for various brain tumors and functional disorders. Current gamma knife radiosurgery is planned in a 'ball-packing' approach and delivered in a 'step-and-shoot' manner, i.e. it aims to 'pack' the different sized spherical high-dose volumes (called 'shots') into a tumor volume. We have developed a dynamic scheme for gamma knife radiosurgery based on the concept of 'dose-painting' to take advantage of the new robotic patient positioning system on the latest Gamma Knife C(TM) and Perfexion(TM) units. In our scheme, the spherical high dose volume created by the gamma knife unit will be viewed as a 3D spherical 'paintbrush', and treatment planning reduces to finding the best route of this 'paintbrush' to 'paint' a 3D tumor volume. Under our dose-painting concept, gamma knife radiosurgery becomes dynamic, where the patient moves continuously under the robotic positioning system. We have implemented a fully automatic dynamic gamma knife radiosurgery treatment planning system, where the inverse planning problem is solved as a traveling salesman problem combined with constrained least-square optimizations. We have also carried out experimental studies of dynamic gamma knife radiosurgery and showed the following. (1) Dynamic gamma knife radiosurgery is ideally suited for fully automatic inverse planning, where high quality radiosurgery plans can be obtained in minutes of computation. (2) Dynamic radiosurgery plans are more conformal than step-and-shoot plans and can maintain a steep dose gradient (around 13% per mm) between the target tumor volume and the surrounding critical structures. (3) It is possible to prescribe multiple isodose lines with dynamic gamma knife radiosurgery, so that the treatment can cover the periphery of the target volume while escalating the dose for high tumor burden regions. (4) With dynamic gamma knife radiosurgery, one can

  11. IMEF gamma scanning system

    Energy Technology Data Exchange (ETDEWEB)

    Baek, Sang Yeol; Park, Dae Kyu; Ahn, Sang Bok; Ju, Yong Sun; Jeon, Yong Bum

    1997-06-01

    The gamma scanning system which is installed in IMEF is the equipment obtaining the gamma ray spectrum from irradiated fuels. This equipment could afford the useful data relating spent fuels like as burn-up measurements. We describe the specifications of the equipment and its accessories, and also described its operation procedure so that an operator can use this report as the operation procedure. (author). 1 tab., 11 figs., 11 refs.

  12. IMEF gamma scanning system

    International Nuclear Information System (INIS)

    Baek, Sang Yeol; Park, Dae Kyu; Ahn, Sang Bok; Ju, Yong Sun; Jeon, Yong Bum.

    1997-06-01

    The gamma scanning system which is installed in IMEF is the equipment obtaining the gamma ray spectrum from irradiated fuels. This equipment could afford the useful data relating spent fuels like as burn-up measurements. We describe the specifications of the equipment and its accessories, and also described its operation procedure so that an operator can use this report as the operation procedure. (author). 1 tab., 11 figs., 11 refs

  13. External radiation exposure after deposition of man-made radionuclides

    International Nuclear Information System (INIS)

    Jacob, P.

    1991-01-01

    The first step in assessing the external radiation exposure of the population is the determination of the gamma dose rate over meadows, which are used as reference points for various reasons. The second step is the description of external radiation exposures in urban and rural environments. The relation to the radiation exposure in a meadow is a function of the radionuclide distribution, i.e. the type of deposition. Finally, a simple method of calculating external radiation exposure is developed on the basis of recent findings. The method is compared with the method used in the UNSCEAR report for calculating radiation exposures after Chernobyl and with the method described in the AVV (General Administrative Regulation) of the Radiation Protection Ordinance. (orig./HP) [de

  14. External Measures of Cognition

    Directory of Open Access Journals (Sweden)

    Osvaldo eCairo

    2011-10-01

    Full Text Available The human brain is undoubtedly the most impressive, complex and intricate organ that has evolved over time. It is also probably the least understood, and for that reason, the one that is currently attracting the most attention. In fact, the number of comparative analyses that focus on the evolution of brain size in Homo sapiens and other species has increased dramatically in recent years. In neuroscience, no other issue has generated so much interest and been the topic of so many heated debates as the difference in brain size between socially defined population groups, both its connotations and implications. For over a century, external measures of cognition have been related to intelligence. However, it is still unclear whether these measures actually correspond to cognitive abilities. In summary, this paper must be reviewed with this premise in mind.

  15. Hanford External Dosimetry Program

    International Nuclear Information System (INIS)

    Fix, J.J.

    1990-10-01

    This document describes the Hanford External Dosimetry Program as it is administered by Pacific Northwest Laboratory (PNL) in support of the US Department of Energy (DOE) and its Hanford contractors. Program services include administrating the Hanford personnel dosimeter processing program and ensuring that the related dosimeter data accurately reflect occupational dose received by Hanford personnel or visitors. Specific chapters of this report deal with the following subjects: personnel dosimetry organizations at Hanford and the associated DOE and contractor exposure guidelines; types, characteristics, and procurement of personnel dosimeters used at Hanford; personnel dosimeter identification, acceptance testing, accountability, and exchange; dosimeter processing and data recording practices; standard sources, calibration factors, and calibration processes (including algorithms) used for calibrating Hanford personnel dosimeters; system operating parameters required for assurance of dosimeter processing quality control; special dose evaluation methods applied for individuals under abnormal circumstances (i.e., lost results, etc.); and methods for evaluating personnel doses from nuclear accidents. 1 ref., 14 figs., 5 tabs

  16. Bevalac external beamline optics

    Energy Technology Data Exchange (ETDEWEB)

    Kalnins, J.G.; Krebs, G.F.; Tekawa, M.M.; Alonso, J.R.

    1987-04-01

    This handbook is intended as an aid for tuning the external particle beam (EPB) lines at the Lawrence Berkeley Laboratory's Bevalac. The information contained within will be useful to the Bevalac's Main Control Room and experimenters alike. First, some general information is given concerning the EPB lines and beam optics. Next, each beam line is described in detail: schematics of the beam line components are shown, all the variables required to run a beam transport program are presented, beam envelopes are given with wire chamber pictures and magnet currents, focal points and magnifications. Some preliminary scaling factors are then presented which should aid in choosing a given EPB magnet's current for a given central Bevalac field. Finally, some tuning hints are suggested.

  17. Bevalac external beamline optics

    International Nuclear Information System (INIS)

    Kalnins, J.G.; Krebs, G.F.; Tekawa, M.M.; Alonso, J.R.

    1987-04-01

    This handbook is intended as an aid for tuning the external particle beam (EPB) lines at the Lawrence Berkeley Laboratory's Bevalac. The information contained within will be useful to the Bevalac's Main Control Room and experimenters alike. First, some general information is given concerning the EPB lines and beam optics. Next, each beam line is described in detail: schematics of the beam line components are shown, all the variables required to run a beam transport program are presented, beam envelopes are given with wire chamber pictures and magnet currents, focal points and magnifications. Some preliminary scaling factors are then presented which should aid in choosing a given EPB magnet's current for a given central Bevalac field. Finally, some tuning hints are suggested

  18. Synthesis Of Silver Nanoparticles Supported On Silica Using As Antifungal Agent By Gamma Irradiation

    International Nuclear Information System (INIS)

    Nguyen Thi Kim Lan; Nguyen Tue Anh; Dang Van Phu; Vo Kim Lang; Nguyen Thuy Khanh; Nguyen Quoc Hien

    2011-01-01

    Silver nanoparticles supported on silica (Ag nano/SiO 2 ) were prepared by gamma Co-60 irradiation method. The formation of Ag nano doped on silica particles was confirmed by the UV-Vis spectroscopy. The size of silver nanoparticles was characterized by transmission electron microscopy (TEM), X-ray diffraction (XRD) which showed the particle size of Ag nano to be in range of 15-30 nm for Ag + concentration 10 mM. In addition, antifungal activity of Ag nano/SiO 2 was tested against Aspergillus niger var Tieghn by plate count method. The results indicated that the antifungal efficiency of Ag nano/SiO 2 was about 64, 71, 81, 82 and 96% at the concentrations of Ag nanoparticles of 30, 50, 70, 100 and 150 ppm respectively. (author)

  19. Effect of gamma irradiation on the activity of monoamine oxidase in the hypothalamus of ewes

    International Nuclear Information System (INIS)

    Pastorova, B.; Stanikova, A.

    2008-01-01

    The study investigated changes in monoamine oxidase (MAO) activity in the hypothalamus of ewes in the anoestrous period exposed to a whole body Co-60 irradiation with a total dose of 6.7 Gy for the period of 7 days. The activity of MAO was determined by means of a radiochemical method using C-14 tryptamine as a substrate. Whole body exposure to gamma radiation of total dose of 6.7 Gy increased significantly (P < 0.001) the activity of MAO in the caudal, medial and rostral hypothalamus of the investigated ewes. It may by assumed that an increased degradation of catecholamines caused by MAO is one of the mechanisms responsible for pronounced changes in the level of catecholamines in the hypothalamus of ewes after irradiation. (authors)

  20. Production of polytetrafluoroethylene by means of polymerization induced by gamma radiation

    International Nuclear Information System (INIS)

    Sugao, A.B.

    1986-01-01

    The process of polytetrafluoroethylene (PTFE) production, is studied. The TFE monomer was prepared by pyrolisis of clorodifluoromethane (R-22) and purified by low temperature fractional distillation. The bulk polymerization of tetrafluoroethylene (TFE) induced by gamma rays from a 185 TBq (5000 Ci) Co-60 source was studied at several temperatures (0 0 C, -23 0 C e -78 0 C). The purified monomer was introduced into stainless steel cylindres of 15 and 60 ml under vacuum. Glass cylindres of 10,50 and 700 ml were also used for irradiation at -78 0 C. The polymer was obtained as white agglomerated particles. The I.R. spectra of polymer samples were consistent with those of commercial PTFE. The melting points of samples were between 327 and 331 0 C. (Author) [pt

  1. Ten year experience in operation of a sewage sludge treatment plant using gamma irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Lessel, T [Abwasserverband Ampergruppe, Eichenau/Muenchen (Germany, F.R.); Suess, A [Bayerische Landesanstalt fuer Bodenkultur und Pflanzenbau, Muenchen (Germany, F.R.)

    1984-01-01

    The first sewage sludge gamma irradiation plant in a technical scale, using Co-60 has been successfully working in Geiselbullach near Munich, FRG, since July 1973. More than 250,000 m/sup 3/ of liquid sludge has been disinfected during that time. Very simple plant design, fully automatic operation over 24 hours and high availability proved the practical applicability of such a facility in a sewage water purification plant without any specially skilled personnel. Beside wide investigations for hygienic aspects, changing of the physical sludge characteristics, effect of irradiated sludge on soil and plants the economic considerations were regarded as important. Experiments were undertaken to optimize the flexibility of the plant operation and to reduce the necessary radiation dose for minimizing the operation costs.

  2. Characterization of three digital signal processor systems used in gamma ray spectrometry

    International Nuclear Information System (INIS)

    Reguigui, N.; Morel, J.; Ben Kraiem, H.; Mahjoub, A.

    2002-01-01

    Various manufacturers have recently introduced digital signal processing systems that allow data acquisition in gamma spectrometry at high-input counting rates (several thousand pulses per second). In these systems, the signal digitization is performed immediately following the preamplification stage. This allows digital shaping and filtering of the signal which increases the number of possible combinations in signal shaping and as a consequence, optimizes the resolution as a function of the detector characteristics and the counting rate. Basic characteristic parameters of three digital signal processors that were recently introduced in the market have been studied and compared to those of an analog system. This study is carried out using a hyper-pure coaxial type germanium detector and 57 Co, 60 Co and 137 Cs radioactive sources. Performance parameters such as energy resolution, system throughput, and counting losses that are due to dead time and pile-up effects are presented and discussed

  3. Gamma irradiation of the face fly Musca autumnalis DeGeer (Diptera: Muscidae)

    International Nuclear Information System (INIS)

    Gregory, D.J.

    1974-01-01

    Pupae of the face fly were irradiated at 5 days of age using gamma radiation from a Co-60 source. Experiments were conducted to determine the effect of radiation dose on the fertility and longevity of the resulting adults. An irradiation dose of 2.5 krad induced permanent sterility in both males and females without affecting their longevity significantly. Competitive and mating tests indicated that males irradiated at 2.5 krad were as competitive as normal males. A colony of flies was infected with the nematode parasite, Heterotylenchus autumnalis Nickle. Irradiation of parasitized, 5-day-old pupae, indicated that the parasite was not adversely affected by radiation doses of 1.0 and 2.5 krad. (author)

  4. Regulatory inspection of the egyptian gamma irradiator using a proposed inspection checklist

    International Nuclear Information System (INIS)

    Abdel-Ghani, A.H.

    2000-01-01

    Regulatory inspections are one of the most important elements of a regulatory programme. It shall be performed in all areas of the regulatory responsibility and during all phases of siting, design, construction, commissioning, operation, maintenance and decommissioning of an irradiator facility. The egyptian mega gamma irradiator operating since december 1979 has a Co-60 source of about 400 kilo curies and is used mainly for sterilization of medical supplies and pharmaceuticals and for preservation of some food stuffs. The constructor (Nordion international Inc.) recommended an extensive inspection programme. In accordance with the international and national (2.3) regulations as well as the licensing conditions, the competent authority (NCNSRC) shall perform regulatory inspections both announced and unannounced. In order to facilitate the inspection task and to harmonize the inspection reports a checklist for inspection is proposed which can be used also as an inspection report form

  5. Improvement of plant parameters of the ROBO gamma irradiation facility due to design modification

    International Nuclear Information System (INIS)

    Moussa, A.; Othman, I.; Chu, R.

    1999-01-01

    Two industrial scale, ROBO type Co 60 gamma irradiation facilities have recently been put into operation in Syria and Peru, and the dosimetry commissioning of both plants have been carried out to determine dose distribution with products and to calculate plant parameters such as efficiency, dose uniformity ratio and throughput. There are some design modifications between the two plants in connection with the location of the carriers with respect to the source plaque and also to each other. The effect of these construction modifications on the plant parameters is discussed in the analysis of the dose distribution data measured in the carriers with depth and height among the four irradiation rows on both sides of the source plaque. The plant parameters were also calculated and measured results were compared to each other. (author)

  6. Gamma irradiation effects on larval and pupal stages on the saw toothed grain beetle oryzaephilus

    International Nuclear Information System (INIS)

    Younes, M.W.; Ahmed, M.Y.Y.

    1978-01-01

    Effects of gamma irradiation from Co 60 on larval and pupal stages of the saw-toothed grain beetle. Oryzaephilus surinamensis L. were determined. Larval and pupal sensitivity depended on age at treatment, the older the larvae or pupae, the less susceptible. No adults emerged in the 10- to 12-day larvae and 4-day old pupae when irradiated at 10 and 100 Krad. respectively. Irradiation of larvae and pupae especially at high doses, resulted in reduced percent adult emergence in incomplete emergence, and in structural deformities. The percentage sterility for both sexes at each dosage used were determined. Males and females irradiated asl-d and 4-d-old pupae, then mated with normal unmated adults of the opposite sex laid infertile eggs when irradiated at 12 Krad. Adult mortality from irradiated pupae (1- or 4-d-old) was increased with the increase of the dose

  7. Sterilization of oriental fruit fly by gamma irradiation and its effect on competitiveness

    International Nuclear Information System (INIS)

    Manoto, E.C.; Bautista, R.C.

    1975-01-01

    The Oriental fruit fly, Dacus dorsalis Hendel, was irradiated with 5, 7, or 9 krad of Co-60 gamma rays at one or two days before adult eclosion. It was not clear whether or not male fruit flies were more competitive when irradiated at two days than at one day before adult eclosion. A dose of 5 krad was considered better than the higher doses of 7 or 9 krad because the higher the dosages increased percentage sterility of the male only slightly from 99.8% at 5 krad but considerably reduced male competitiveness from 72% at 5 krad to 52% at 9 krad for flies treated 2 days before emergence. The lowest dose of 5 krad was enough to prevent the female fruit flies from laying any egg. Irradiation at any of the dose levels did not affect the number of adults that emerged and the longevity of the fruit flies up to 38 days after adult eclosion

  8. Influence of gamma-radiation on the biological activity of snake venoms in Peru

    International Nuclear Information System (INIS)

    Yarleque Ch, A.

    1986-03-01

    Effects of Co-60 gamma radiation on enzymatic, haemorragic and necrotic activities of Lachesis muta and Bothrops atrox venoms was studied at several ranges of irradiation lower than 1.0 Mrad. The radiation produced changes on its enzymatic activities. Irradiation at 0.1 Mrad resulted in the partial or complete inactivation of the following enzymes that are listed in order of increasing sensitivity: exonuclease, phospholipase A, caseinolytic enzyme, thrombinolytic enzyme, fibrinolytic enzyme, 5'-nucleotidase and endonuclease. The enzymatic inactivation was increased with 0.5 and 1.0 Mrad although not in a linear manner. Exonuclease was found to be the most radioresistant. The haemorragic activity was decreased to a greater extent than the necrotic activity. The probable mechanism for the changes in the enzymatic, haemorragic and necrotic activities are discussed

  9. Ten year experience in operation of a sewage sludge treatment plant using gamma irradiation

    International Nuclear Information System (INIS)

    Lessel, T.; Suess, A.

    1984-01-01

    The first sewage sludge gamma irradiation plant in a technical scale, using Co-60 has been successfully working in Geiselbullach near Munich, FRG, since July 1973. More than 250,000 m 3 of liquid sludge has been disinfected during that time. Very simple plant design, fully automatic operation over 24 hours and high availability proved the practical applicability of such a facility in a sewage water purification plant without any specially skilled personnel. Beside wide investigations for hygienic aspects, changing of the physical sludge characteristics, effect of irradiated sludge on soil and plants the economic considerations were regarded as important. Experiments were undertaken to optimize the flexibility of the plant operation and to reduce the necessary radiation dose for minimizing the operation costs. (author)

  10. Building Protection Against External Ionizing Fallout Radiation

    Energy Technology Data Exchange (ETDEWEB)

    Dillon, Michael B. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Homann, Steven G. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2016-12-01

    A nuclear explosion has the potential to injure or kill tens to hundreds of thousands of people through exposure to fallout (external gamma) radiation. Existing buildings can protect their occupants (reducing external radiation exposures) by placing material and distance between fallout particles and indoor individuals. This protection is not well captured in current fallout risk assessment models and so the US Department of Defense is implementing the Regional Shelter Analysis methodology to improve the ability of the Hazard Prediction and Assessment Capability (HPAC) model to account for building protection. This report supports the HPAC improvement effort by identifying a set of building attributes (next page) that, when collectively specified, are sufficient to calculate reasonably accurate, i.e., within a factor of 2, fallout shelter quality estimates for many individual buildings. The set of building attributes were determined by first identifying the key physics controlling building protection from fallout radiation and then assessing which building attributes are relevant to the identified physics. This approach was evaluated by developing a screening model (PFscreen) based on the identified physics and comparing the screening model results against the set of existing independent experimental, theoretical, and modeled building protection estimates. In the interests of transparency, we have developed a benchmark dataset containing (a) most of the relevant primary experimental data published by prior generations of fallout protection scientists as well as (b) the screening model results.

  11. Adaptive response of yeast cultures (Saccharomyces Cerevisiae) exposed to low dose of gamma radiation

    International Nuclear Information System (INIS)

    Kulcsar, Agnes; Savu, D.; Petcu, I.; Gherasim, Raluca

    2003-01-01

    The present study was planned as follows: (i) setting up of standard experimental conditions for investigation of radio-induced adaptive response in lower Eucaryotes; (ii) developing of procedures for synchronizing Saccharomyces cerevisiae X 310 D cell cultures and cell cycle stages monitoring; (iii) investigation of gamma (Co-60) and UV irradiation effects on the viability of synchronized and non-synchronized cell cultures of Saccharomyces cerevisiae; the effects were correlated with the cell density and cell cycle stage; (iv) study of the adaptive response induced by irradiation and setting up of the experimental conditions for which this response is optimized. The irradiations were performed by using a Co-60 with doses of 10 2 - 10 4 Gy and dose rates ranging from 2.2 x 10 2 Gy/h to 8.7 x 10 3 Gy/h. The study of radioinduced adaptive response was performed by applying a pre-irradiation treatment of 100-500 Gy, followed by challenge doses of 2-4 kGy delivered at different time intervals, ranging from 1 h to 4 h. The survival rate of synchronized and non-synchronized cultures as a function of exposure dose shows an exponential decay shape. No difference in viability of the cells occurred between synchronized and non-synchronized cultures. The pre-irradiation of cells with 100 and 200 Gy were most efficient to induce an adaptive response for the yeast cells. In this stage of work we proved the occurrence of the adaptive response in the case of synchronized yeast cultures exposed to gamma radiation. The results will be used in the future to investigate the dependence of this response on the cell cycle and the possibility to induce such a response by a low level electromagnetic field. (authors)

  12. Effects of Gamma Irradiation on Quality in the Processing of Low Salted and Fermented Shrimp

    International Nuclear Information System (INIS)

    Shin Myung-Gon; Lee Cherl-Ho

    2000-01-01

    Irradiation technology was applied to develop low salted and fermented shrimp that has better sensory quality and a longer shelf-life without any food additives. Different levels of salt (10, 15, and 20%, w/w) were added to the salted and fermented shrimp and the samples were irradiated at 0, 2.5, 5.0, 7.5, and 10.0 kGy with a gamma source (Co-60). Proximate composition, salinity, water activity (a), pH, total bacterial count, and general acceptance were analyzed during fermentation at 15 degrees after irradiation. The proximate analysis, salinity, and a were not affected by gamma irradiation during fermentation. However, pH and total bacteria, as well as sensory evaluation, were changed variously with processing conditions such as sodium chloride concentration and irradiation dose. The combinations of 15% salt concentration with 10 kGy irradiation dose and 20% with 5 kGy or above were effective for shelf-life enhancement of the salted and fermented shrimp by adequate suppression of microorganisms during fermentation at 15 degrees. The results showed that the sensory quality of the sample was maintained up to 10 weeks after fermentation. Therefore, it was considered that gamma irradiation was effective in processing low salted and fermented shrimp and extending their shelf-life without adding any food additives

  13. TL glow curve analysis of UV, beta and gamma induced limestone collected from Amarnath holy cave

    Directory of Open Access Journals (Sweden)

    Vikas Dubey

    2015-01-01

    Full Text Available The paper reports themoluminescence glow curve analysis of UV (ultraviolet, β (beta and γ (gamma induced limestone collected from Amarnath holy cave. The collected natural sample was characterized by X-ray diffraction (XRD technique and crystallite size calculated by Scherer's formula. Surface morphology and particle size was calculated by transmission electron microscopy (TEM study. Effect of annealing temperature on collected lime stone examined by TL glow curve study. The limestone was irradiated by UV radiation (254 nm source and the TL glow curve recorded for different UV exposure time. For beta irradiation Sr90 source was used and is shows intense peak at 256 °C with a shoulder peak at higher temperature range. For gamma radiation Co60 source and TL glow curve recorded for different doses of gamma. The kinetic parameters calculation was performed for different glow curve by computerized glow curve deconvolution (CGCD technique. The chemical composition of natural limestone was analyzed by energy dispersive X-ray spectroscopy (EDXS.

  14. Radioisotope identification method for poorly resolved gamma-ray spectrum of nuclear security concern

    International Nuclear Information System (INIS)

    Ninh, Giang Nguyen; Phongphaeth, Pengvanich; Nares, Chankow; Hao, Quang Nguyen

    2016-01-01

    Gamma-ray signal can be used as a fingerprint for radioisotope identification. In the context of radioactive and nuclear materials security at the border control point, the detection task can present a significant challenge due to various constraints such as the limited measurement time, the shielding conditions, and the noise interference. This study proposes a novel method to identify the signal of one or several radioisotopes from a poorly resolved gamma-ray spectrum. In this method, the noise component in the raw spectrum is reduced by the wavelet decomposition approach, and the removal of the continuum background is performed using the baseline determination algorithm. Finally, the identification of radioisotope is completed using the matrix linear regression method. The proposed method has been verified by experiments using the poorly resolved gamma-ray signals from various scenarios including single source, mixing of natural uranium with five of the most common industrial radioactive sources (57Co, 60Co, 133Ba, 137Cs, and 241Am). The preliminary results show that the proposed algorithm is comparable with the commercial method

  15. Radioisotope identification method for poorly resolved gamma-ray spectrum of nuclear security concern

    Energy Technology Data Exchange (ETDEWEB)

    Ninh, Giang Nguyen; Phongphaeth, Pengvanich, E-mail: phongphaeth.p@chula.ac.th; Nares, Chankow [Nuclear Engineering Department, Faculty of Engineering, Chulalongkorn University, 254 Phayathai Road, Pathumwan, Bangkok 10330 (Thailand); Hao, Quang Nguyen [Vietnam Atomic Energy Institute, Ministry of Science and Technology, Hanoi (Viet Nam)

    2016-01-22

    Gamma-ray signal can be used as a fingerprint for radioisotope identification. In the context of radioactive and nuclear materials security at the border control point, the detection task can present a significant challenge due to various constraints such as the limited measurement time, the shielding conditions, and the noise interference. This study proposes a novel method to identify the signal of one or several radioisotopes from a poorly resolved gamma-ray spectrum. In this method, the noise component in the raw spectrum is reduced by the wavelet decomposition approach, and the removal of the continuum background is performed using the baseline determination algorithm. Finally, the identification of radioisotope is completed using the matrix linear regression method. The proposed method has been verified by experiments using the poorly resolved gamma-ray signals from various scenarios including single source, mixing of natural uranium with five of the most common industrial radioactive sources (57Co, 60Co, 133Ba, 137Cs, and 241Am). The preliminary results show that the proposed algorithm is comparable with the commercial method.

  16. Effect Of Gamma Irradiation On Microbiological Properties Of Frozen Durian Pulp And Puree

    International Nuclear Information System (INIS)

    Sofian Ibrahim; Cosmos, George; Noor Hasni Mohd Ali; Zarina Mohd Nor; Syuhadah Ramli; Jamilah Karim; Ahsanulkhaliqin Abdul Wahab; Mohd Khairul Azfar Ramli; Mohd Sidek Othman

    2013-01-01

    Studies on effects of gamma irradiation on the frozen Durian fruit (Durio zibethinus Murray) was conducted in MINTec-Sinagama, Malaysian Nuclear Agency, using a Co-60 source. The main aims of the study were to determine the optimum range of gamma irradiation dose can be applied on frozen durian pulp and puree to improve the microbial quality whilst maintaining its flavor. The results showed that the generic gamma radiation dose between 2 kGy until 6 kGy can reduced total plate count (TPC) of the recorded initial TPC values of fresh durian pulp and puree; 6.10 x 10 5 and 3.79 x 10 5 cfu/ g each into the range of 2.54 x 10 5 to 1.58 x 10 3 cfu/ g and 1.18 x 10 5 to 3.08 x 10 3 cfu/ g respectively. In conclusion, the non-thermal irradiation improved the microbial quality of durian whilst maintaining its flavor. (author)

  17. Improving Quality and Microbial Safety of Wheat Flour by Gamma Irradiation

    International Nuclear Information System (INIS)

    Hammad, A.A.; Hassan, M.F.; Soliman, S.M.; Abu-Shady, M.R.

    2017-01-01

    In the present study Egyptian wheat flour extracted from wheat (variety Seds 6 ) were irradiated at a dose of 5.0 kGy using Co-60 gamma source. The influence of this irradiation dose on the aerobic bacterial count, mold and yeast count, aflatoxins and major chemical composition of wheat flour was investigated. The influence of a 5.0 kGy gamma radiation dose on the rheological characteristics of wheat flour as well as on the sensory properties of Balady bread was also investigated. It was found that irradiation greatly reduced aerobic bacterial count and mold and yeast count as well as decreasing aflatoxin B1. The major chemical composition of wheat flour almost had no changes as a result of exposure to gamma radiation. An irradiation dose of 5.0 kGy caused a decrease in dough development time, dough stability time and deformation energy of dough as well as increasing dough water absorption which are all desirable in bread making. On the other hand, sensory properties of bread prepared from irradiated flour were almost similar to that of bread made from non-irradiated flour

  18. Effect of Black Grape Juice against Heart Damage from Acute Gamma TBI in Rats

    Directory of Open Access Journals (Sweden)

    Edson Ramos de Andrade

    2013-09-01

    Full Text Available The aim of this study was to evaluate the potential positive effect of black grape juice (BGJ on lipid peroxidation considering Total Body Irradiation (TBI in Wistar rats. As a potential feasible means of evaluation in situ, blood serum lactate dehydrogenase (LDH levels were evaluated as a marker for heart damage from acute radiation syndrome (ARS. Twenty rats were divided into four groups, two of them being irradiated by gamma-rays from a Co-60 source. Animals were treated by gavage with 2 mL per day of BGJ or placebo for one week before and 4 days after 6 Gy whole body gamma-irradiation, when they were euthanasiated. LDH on serum and lipid peroxidation on heart tissue were evaluated. High concentration of metabolites from lipid peroxidation in heart, and high LDH level on serum were found only in gamma-irradiated group given placebo, mainly at the first 24 h after radiation. Phytochemical analysis of BGJ was performed by determining total phenolics, flavonoids, and tannins followed by a high-performance liquid chromatography (HPLC/DAD analysis, which showed resveratrol as the major constituent. Results suggest that BGJ is a good protective candidate compound against heart damage from ARS and its effects suggest its use as a radiomodifier.

  19. Mutation induction by gamma irradiation in a triploid banana Pisang Berangan

    International Nuclear Information System (INIS)

    Mak, C.; Liew, K.W.

    1995-01-01

    Shoot-tip meristems of triploid banana Pisang Berangan (Intan cultivar) were irradiated at 0, 25, 35, 45 and 60 Gy in gamma cell with a Co-60 source. The explants were in-vitro multiplied to produce M sub 1 V sub 4 plants. Increasing gamma doses caused a reduction of survival rates as well as the average number of buds or shoots produced per explant. On the basis of linear estimate of bud/shoot proliferation to gamma doses, the radiation dose that reduced the growth to 50% of the control treatment, i.e. LD sub 50 was about 38 Gy. Many phenotypic variants in growth, leaf deformation and changes in pigmentation and texture were observed in nursery plants. In addition, field-grown plants also produced various forms of bunch and fruit abnormality. Generally, mutagenic treatments resulted in a 4 to 6 fold increase in the frequency of variant plants. For number of weeks to harvest and plant height, the mean values of irradiated plants did not differ significantly from the control plants. However, mutation induction tended not only to increase the variability of these two quantitative traits but also showed a much higher frequency for plants having early fruiting or shorter plant stature. As in-vitro mutation induction could create genetic variability as well as many undesirable variants, it is highly desirable to integrate in-vitro mutation with a selection system that can screen for large mutagen treated populations

  20. Quarantine treatment in eggs of Stenoma catenifer Walsingham (Lepidoptera: Elachistidae), with gamma radiation of Cobalt-60

    International Nuclear Information System (INIS)

    Silva, L.K.F.; Arthur, V.; Nava, D.E.; Parra, J.R.P.

    2006-01-01

    The objective of this work has been to determine the lethal dose of gamma radiation of Cobalt-60 for the Stenoma catenifer eggs. For the irradiation of the eggs an irradiador Gammacell-220 (CO60) was utilized, (Rate dose: 1.054 kGY/h). The doses were: 0, 25, 50, 75, 100, 125 and 150 Gy, 90 eggs/dose (six repetitions). The number of caterpillars emerged was evaluated, and the survivors growed in seeds of avocado. The adults obtained were coupled with normal insects, growed in boxes with double face paper containing the food (10% honey) and a fruit of avocado. The experimental design was totally random, being the data submitted to the analysis of the varianza and the averages compared by the test of Tukey (P=5%). The emergence of caterpillars from the treated eggs with dose of 0, 25 and 50 Gy was verified. The dose of 50 Gy caused deformation in the caterpillars emerged. The effect of the gamma radiation in the viability of the eggs was proportional to the dose increase. The adults from the eggs dealt with 25 Gy presented non viabilty of 92,85 and 100% for male and female, respectively. A radiation gamma of 75 Gy is recommended for treatment quarantine for avocado fruits infested with of S. catenifer eggs

  1. Embedded gamma spectrometry: new algorithms for spectral analysis

    International Nuclear Information System (INIS)

    Martin-Burtart, Nicolas

    2012-01-01

    Airborne gamma spectrometry was first used for mining prospecting. Three main families were looked for: K-40, U-238 and Th-232. The Chernobyl accident acted as a trigger and for the last fifteen years, a lot of new systems have been developed for intervention in case of nuclear accident or environmental purposes. Depending on their uses, new algorithms were developed, mainly for medium or high energy signal extraction. These spectral regions are characteristics of natural emissions (K-40, U-238 and Th-232 decay chains) and fissions products (mainly Cs-137 and Co-60). Below 400 keV, where special nuclear materials emit, these methods can still be used but are greatly imprecise. A new algorithm called 2-windows (extended to 3), was developed. It allows an accurate extraction, taking the flight altitude into account to minimize false detection. Watching radioactive materials traffic appeared with homeland security policy a few years ago. This particular use of dedicated sensors require a new type of algorithms. Before, one algorithm was very efficient for a particular nuclide or spectral region. Now, we need algorithm able to detect an anomaly wherever it is and whatever it is: industrial, medical or SNM. This work identified two families of methods working under these circumstances. Finally, anomalies have to be identified. IAEA recommend to watch around 30 radionuclides. A brand new identification algorithm was developed, using several rays per element and avoiding identifications conflicts. (author) [fr

  2. Gamma and proton induced degradation in ceramics materials - A proposal

    International Nuclear Information System (INIS)

    Constantinescu, B.

    2001-01-01

    Ceramic materials will play very important roles in developing fusion reactors, where they will be used under heavy irradiation environments (neutrons, gamma-rays, protons, helium and other ions) for substantial periods for the first time. The programme at the Institute of Atomic Physics in Bucharest forms a part of the on going ceramics programmes to assess the suitability of SiO2 based materials for both diagnostic and remote handling application. The authors' proposal focuses on comparison of the ionization and displacement induced damage (influence on the UV and visible optical transmission properties) and on radiation enhanced hydrogen isotope diffusion in these materials; the work is performed in cooperation with CIEMAT Madrid and SCK/CEN Mol. The irradiation facilities are: IRASM - 200 kCi Co-60 source, minimum 2kGy/h, ethanol chlorine benzene and ESR dosimetry; HVEC 8 MV TANDEM - protons up to 16 MeV and 200 nA; and 600 kV DISKTRON - H isotopes up to 600 keV, tens of microamperes. (author)

  3. Influences of the GAMMA radiation on useful life of strawberry

    International Nuclear Information System (INIS)

    Bonilla B, Ligia M.; Sepulveda P, Claudia M.

    1993-01-01

    The present investigation was carried out with the purpose of prolonging the useful life of strawberry (bird variety) by means of gamma radiation, eliminating the causing microorganisms of the deterioration of the fruit partially: aerobic mesophyll, psicrotrophos, molds and yeasts, effect that was controlled by means of the recount of the same ones. In the same way, it was carried out a quantitative analysis of some parameters such organolitics as flavor, color and hardness, to observe the behavior of the strawberry with the different applied treatments. The irradiation process was made with a source of Co-60, provided by the INEA with an activity of 82 kilo curios. The used radiation doses were 0, 1.0, 1.5, 2.0, 2.5 and 3.0 kGy, which were quantified by means of chemical dosimeter : Sulfate cupric ferrous-sulfate. Strawberries were storage under refrigeration with controlled conditions of temperature between 1 and 2 C and relative humidity of 85-90, and periodically, samples were removed for different analyses

  4. Gamma irradiation effect on thermo shrink polyethylene tube: Case study

    International Nuclear Information System (INIS)

    Naurah Mat Isa; Siti Zulaiha Hairaldin; Mohd Yusof Hamzah; Zulkafli Ghazali

    2010-01-01

    The production technology of heat shrinkable tubes is based on the industrial usage of so-called memory effect in some polymers. Many polymers can be rendered heat shrinkable, particularly polyolefins by introducing crosslinking in the polymer backbone. Heat shrinkable tubes and moulded parts provide mechanical and/or chemical and/or electrical protection. . In this work, irradiation from Co-60 was used to impart crosslinking in polymer and thus modify their mechanical and thermal properties. Heat shrinkable or thermo shrink polyethylene (PE) tube with diameter 6.4 mm was selected to evaluate crosslinking behaviour from the gamma irradiation exposure at 5 different doses (120, 140, 160, 200 and 220 kGy). The gel content (%), tensile properties and thermal behavior and stability of the tubes were measured using DSC and TGA. Tubes irradiated at 140 kGy and 160 kGy showed better tensile properties than those at 120, 200 and 220 kGy doses. Maximum percent of crystallization was observed at 160 kGy and temperature required to crystallize is lower than melting temperature due to changes in molecular orientation. Thermal decomposition of the irradiated tubes occurred at 430-450 degree Celsius which is lower than the unirradiated sample. Gel content analysis for samples irradiated at 180-220 kGy yield up to 30 to 40 % gel fraction. Although the gel fractions are higher than other dose, the samples are expected to experience chain scission presumably due to localized gel formation. (author)

  5. Elimination of salmonella from fermented pork by gamma irradiation

    International Nuclear Information System (INIS)

    Noochpramul, K.; Loaharanu, P.

    1974-01-01

    A fermented pork product, locally known as ''Nham'', is usually contaminated with salmonella and occasionally with Trichinella spiralis and Taenea solium. This product is always eaten raw as cooking destroys its delicate flavour. A survey made on the MPN of salmonella revealed that much less than 100 salmonella was found in one gram of the product. Nham was inoculated with S. derby, S. anatum, S. newport, or S. paratyphi B, the most common serotypes of salmonella found in this product, at 10 6 , 10 4 , or 10 2 per gram. The inoculated product was irradiated by the gamma beam-650 Co-60 irradiator at 0, 0.1, 0.2, 0.3 or 0.4 Mrad. Dosage at 0.4 Mrad eliminated salmonella as much as 10 6 per g; 0.3 Mrad eliminated 10 6 /g of S. newport and S. paratyphi B and 10 4 /g of S. derby and S. anatum; and 0.2 Mrad eliminated 10 2 /g of all serotypes of salmonella in the product. No changes in the organoleptic properties of irradiated Nham was found when irradiated at 0.3 Mrad or less. Dosage at 0.2 Mrad appeared to be sufficient for commercial irradiation of Nham for the elimination of salmonella

  6. Modeling and simulation of gamma camera

    International Nuclear Information System (INIS)

    Singh, B.; Kataria, S.K.; Samuel, A.M.

    2002-08-01

    Simulation techniques play a vital role in designing of sophisticated instruments and also for the training of operating and maintenance staff. Gamma camera systems have been used for functional imaging in nuclear medicine. Functional images are derived from the external counting of the gamma emitting radioactive tracer that after introduction in to the body mimics the behavior of native biochemical compound. The position sensitive detector yield the coordinates of the gamma ray interaction with the detector and are used to estimate the point of gamma ray emission within the tracer distribution space. This advanced imaging device is thus dependent on the performance of algorithm for coordinate computing, estimation of point of emission, generation of image and display of the image data. Contemporary systems also have protocols for quality control and clinical evaluation of imaging studies. Simulation of this processing leads to understanding of the basic camera design problems. This report describes a PC based package for design and simulation of gamma camera along with the options of simulating data acquisition and quality control of imaging studies. Image display and data processing the other options implemented in SIMCAM will be described in separate reports (under preparation). Gamma camera modeling and simulation in SIMCAM has preset configuration of the design parameters for various sizes of crystal detector with the option to pack the PMT on hexagon or square lattice. Different algorithm for computation of coordinates and spatial distortion removal are allowed in addition to the simulation of energy correction circuit. The user can simulate different static, dynamic, MUGA and SPECT studies. The acquired/ simulated data is processed for quality control and clinical evaluation of the imaging studies. Results show that the program can be used to assess these performances. Also the variations in performance parameters can be assessed due to the induced

  7. Measurement of background gamma radiation in the northern Marshall Islands.

    Science.gov (United States)

    Bordner, Autumn S; Crosswell, Danielle A; Katz, Ainsley O; Shah, Jill T; Zhang, Catherine R; Nikolic-Hughes, Ivana; Hughes, Emlyn W; Ruderman, Malvin A

    2016-06-21

    We report measurements of background gamma radiation levels on six islands in the northern Marshall Islands (Enewetak, Medren, and Runit onEnewetak Atoll; Bikini and Nam on Bikini Atoll; and Rongelap on Rongelap Atoll). Measurable excess radiation could be expected from the decay of (137)Cs produced by the US nuclear testing program there from 1946 to 1958. These recordings are of relevance to safety of human habitation and resettlement. We find low levels of gamma radiation for the settled island of Enewetak [mean = 7.6 millirem/year (mrem/y) = 0.076 millisievert/year (mSv/y)], larger levels of gamma radiation for the island of Rongelap (mean = 19.8 mrem/y = 0.198 mSv/y), and relatively high gamma radiation on the island of Bikini (mean = 184 mrem/y = 1.84 mSv/y). Distributions of gamma radiation levels are provided, and hot spots are discussed. We provide interpolated maps for four islands (Enewetak, Medren, Bikini, and Rongelap), and make comparisons to control measurements performed on the island of Majuro in the southern Marshall Islands, measurements made in Central Park in New York City, and the standard agreed upon by the United States and the Republic of the Marshall Islands (RMI) governments (100 mrem/y = 1 mSv/y). External gamma radiation levels on Bikini Island significantly exceed this standard (P = <0.01), and external gamma radiation levels on the other islands are below the standard. To determine conclusively whether these islands are safe for habitation, radiation exposure through additional pathways such as food ingestion must be considered.

  8. System for gamma-gamma formation density logging while drilling

    International Nuclear Information System (INIS)

    Paske, W.C.

    1991-01-01

    The patent relates to a system for logging subterranean formations for the determination of formation density by using gamma radiation. Gamma ray source and detection means are disposed within a housing adapted for positioning within a borehole for the emission and detection of gamma rays propagating through earth formations and borehole drilling fluid. The gamma ray detection means comprises first and second gamma radiation sensors geometrically disposed within the housing, the same longitudinal distance from the gamma ray source and diametrically opposed in a common plane. A formation matrix density output signal is produced in proportion to the output signal from each of the gamma ray sensors and in conjunction with certain constants established by the geometrical configuration of the sensors relative to the gamma ray source and the borehole diameter. Formation density is determined without regard to the radial position of the logging probe within the borehole in a measuring while drilling mode. 6 figs

  9. The ExternE project: methodology, objectives and limitations

    International Nuclear Information System (INIS)

    Rabl, A.; Spadaro, J.V.

    2002-01-01

    This paper presents a summary of recent studies on external costs of energy systems, in particular the ExternE (External Costs of Energy) Project of the European Commission. To evaluate the impact and damage cost of a pollutant, one needs to carry out an impact pathway analysis; this involves the calculation of increased pollutant concentrations in all affected regions due to an incremental emission (e.g. μg/m 3 of particles, using models of atmospheric dispersion and chemistry), followed by the calculation of physical impacts (e.g. number of cases of asthma due to these particles, using a dose-response function). The entire so-called fuel chain (or fuel cycle) is evaluated and compared on the basis of delivered end use energy. Even though the uncertainties are large, the results provide substantial evidence that the classical air pollutants (particles, NO x and SO x ) from the combustion of fossil fuels impose a heavy toll, in addition to the cost of global warming. The external costs are especially large for coal; even for 'good current technology' they may be comparable to the price of electricity. For natural gas the external costs are about a third to a half of coal. The external costs of nuclear are small compared to the price of electricity (at most a few %), and so are the external costs of most renewable energy systems. (authors)

  10. Effects of gamma radiation on melon read-to-eat

    Energy Technology Data Exchange (ETDEWEB)

    Pires, Juliana A.; Polizel, Francine Fernanda, E-mail: jujuba_angelo@yahoo.com.br, E-mail: fran_sininho@hotmail.com [Faculdade de Tecnologia em Piracicaba (FATEP), Piracicaba, SP (Brazil); Harder, Marcia N.C.; Silva, Lucia C.A.S.; Arthur, Paula B.; Arthur, Valter, E-mail: mnharder@terra.com.br, E-mail: lcasilva@cena.usp.br, E-mail: paula.arthur@hotmail.com, E-mail: arthur@cena.usp.br [Centro de Energia Nuclear na Agricultura (CENA/USP), Piracicaba, SP (Brazil)

    2013-07-01

    This work comes from the irradiation of Cantaloupe melons (Cucumis melo L.), with the aid of gamma irradiation (Co60) to physical and chemical changes to assess their conservation. The research aimed to evaluate the effects of irradiation on melons, including the possibility of conservation, through pH, acidity, soluble solids and fresh squash. The samples were minimally processed and submitted to gamma radiation Co{sup 60} at doses of 0 (control); 1kGy and 2kGy. Physicochemical analyzes were made in periods of 1, 7 and 14 days after irradiation treatment. On day 1 and day 7, pH levels in irradiated samples had increased compared to control. Since the 14th day, the dose decreased 1kGy equaling the control. Soluble solids showed a statistical gradual decrease according to the increase of dose. The 14th had no significant difference while the 7th the dose was increased. The 1kGy sample decreased in another dose compared to the control. In fresh squash, absent statistics were observed for all samples in the three periods. And for the analysis of titratable acidity, there was observed no significant difference at day 1. There was observed a decrease in the 2kGy and 1kGy dose to 7 days compared to the control. On 14th day, a reduction in the dose of 2kGy and deterioration of 1kGy dose of the sample. Therefore, it demonstrates the irradiation doses of 2kGy, 1kGy physic-chemically alters the Cantaloupe melon pH, soluble solids content and acidity. And the dose of 2kGy is the one that longer preserves samples based on acidity values, greater and smaller values of soluble solids. (author)

  11. 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)

  12. Investigation on the effects of gamma irradiation on bitumen

    International Nuclear Information System (INIS)

    Mello, M.S.; Braz, D.; Motta, L.M.G.

    2011-01-01

    Brazil has more than 218,000 km of asphalt-paved highways. Bitumen is a generic term for natural or manufactured black or dark-colored solid, semisolid, or viscous cementitious materials that are composed mainly of high molecular weight hydrocarbons (90-95%). Several papers have shown that the irradiation process has changed the mechanical behavior in some polymers. This work aims to analyze the behavior of Brazilian irradiated Bitumen (CAP 50-70). In order to provide a preliminary evaluation, bitumen samples and cylindrical specimens of asphaltic mixture were tested. The bitumen samples were irradiated 0.1 to 300 kGy, and asphaltic mixture specimen was irradiated 5 to 300 kGy. The cylindrical asphaltic mixture specimen of 10.16 cm diameter used in this study was molded using an asphalt-aggregate mixture. The specimens were irradiated in LIN/UFRJ/Brazil using a Gamma cell Co 60 source of gamma irradiation with an applied dose rate of 29.7 Gy/min. After irradiated, the bitumen samples were subjected to penetration test and the asphaltic mixtures were subjected to indirect tensile strength test (diametral compression) for determination of the resilient modulus, according to ASTM method D 4123. The results of these experiments for each dose were compared with the control (nonirradiated). As expected, the penetration results showed that the ratio (irradiated/non-irradiated) decreases with increasing of irradiation dose for bitumen samples and the resilient modulus results showed that the ratio (irradiated/non-irradiated) increases with increasing of irradiation dose for asphaltic mixture. (author)

  13. Modular gamma systems

    International Nuclear Information System (INIS)

    Millegan, D.R.; Nixon, K.V.

    1982-01-01

    Nuclear safeguards requires sensitive, easily operated instruments for rapid inspection of personnel and vehicles to ensure that no uranium or plutonium is being diverted. Two portable gamma-ray detection systems have been developed. The Modular Gamma System (MGS) is very sensitive and two or more systems can be connected for even better performance. The multiunit configuration can be deployed by motor vehicle for search of large areas too extensive to search on foot. The Programmable Rate Monitor (PRM) is less sensitive but much smaller and therefore is more suitable for search of vehicles, personnel, or smaller areas. The PRM is programmable, which implements measurement and alarm algorithms for individual applications

  14. Proprioceptive evoked gamma oscillations

    DEFF Research Database (Denmark)

    Arnfred, S.M.; Hansen, Lars Kai; Parnas, J.

    2007-01-01

    A proprioceptive stimulus consisting of a weight change of a handheld load has recently been shown to elicit an evoked potential. Previously, somatosensory gamma oscillations have only been evoked by electrical stimuli. We conjectured that a natural proprioceptive stimulus also would be able...... to evoke gamma oscillations. EEG was recorded using 64 channels in 14 healthy subjects. In each of three runs a stimulus of 100 g load increment in each hand was presented in 120 trials. Data were wavelet transformed and runs collapsed. Inter-trial phase coherence (ITPC) was computed as the best measure...

  15. Gamma-Ray Bursts

    Science.gov (United States)

    Pellizza, L. J.

    Gamma-ray bursts are the brightest transient sources in the gamma-ray sky. Since their discovery in the late 1960s, the investigation of the astrophysical sys- tems in which these phenomena take place, and the physical mechanisms that drive them, has become a vast and prolific area of modern astrophysics. In this work I will briefly describe the most relevant observations of these sources, and the models that describe their nature, emphasizing on the in- vestigations about the progenitor astrophysical systems. FULL TEXT IN SPANISH

  16. Gamma Ray Bursts

    Science.gov (United States)

    Gehrels, Neil; Meszaros, Peter

    2012-01-01

    Gamma-ray bursts (GRBs) are bright flashes of gamma-rays coming from the cosmos. They occur roughly once per day ,last typically lOs of seconds and are the most luminous events in the universe. More than three decades after their discovery, and after pioneering advances from space and ground experiments, they still remain mysterious. The launch of the Swift and Fermi satellites in 2004 and 2008 brought in a trove of qualitatively new data. In this review we survey the interplay between these recent observations and the theoretical models of the prompt GRB emission and the subsequent afterglows.

  17. Hopping conduction in gamma-irradiated InSe and InSe:Sn single crystals

    International Nuclear Information System (INIS)

    MUSTAFAEVA, S.N.; ISMAILOV, A.A.; ASADOV, M.M.

    2010-01-01

    Full text : The semiconductive InSe layer compound is characterized by a strong covalent bond inside the layers and a weak Van der Waals bonding between them. It was shown that across the layers of InSe single crystals at low temperatures (T ≤ 200 K) at direct current (dc) hopping conduction through localized states near the Fermi level takes place. The results of dc-conductivity of gamma-irradiated p-InSe and n-InSe : Sn layer single crystals have been presented in this work. ρ-InSe single crystal specimens grown by the Bridgman method were used in the experiments. Plates of the crystals under study were obtained by cleaving along the layers of single crystal ingots. The single-crystal InSe samples for electric measurements had the form of planar capacitors normal to the C axis of the crystals, with silver-paste electrodes. The thickness of the InSe samples was 300 mkm. Co 60 serves as the source of irradiation with energy of gamma-quantum equal to 1.3 MeV. The electric properties of non-irradiated and gamma-irradiated InSe crystals were measured under the same conditions. It is revealed that InSe and InSe : Sn (0.2 and 0.4 mole percent Sn) single crystals exhibit a variable range hopping conduction along a normal to their natural layers at temperatures T≤200 K in a dc electric field. From experimental data the parameters of localized states of p-InSe and n-InSe : Sn were calculated before and after gamma-irradiation. It is revealed that gamma-irradiation of p-InSe and n-InSe : Sn (0.2 and 0.4 mole percent Sn) single crystals leads to significant change of localized states parameters. After gamma-irradiation the density of states near the Fermi level increased, but their energy spread and the average jump distance decreased. The concentrations of radiated defects were estimated in p-InSe (5.18*10 1 7 sm - 3) and n-InSe : Sn (2.5*10 1 7 - 2.7*10 1 8 sm - 3) single crystals. The present results demonstrate that gamma-irradiation offers the possibility of tuning

  18. Treatment of epidermoid tumors with gamma knife radiosurgery: Case series.

    Science.gov (United States)

    Vasquez, Javier A Jacobo; Fonnegra, Julio R; Diez, Juan C; Fonnegra, Andres

    2016-01-01

    Epidermoid tumors (ETs) are benign lesions that are treated mainly by means of surgical resection, with overall good results. External beam radiotherapy is an alternative treatment for those recurrent tumors, in which a second surgery might not be the best choice for the patient. A little information exists about the effectiveness of gamma knife radiosurgery for the treatment of newly diagnosed and recurrent ETs. We present three cases of ETs treated with gamma knife radiosurgery. Case 1 is a 21-year-old female with an ET located in the left cerebellopontine angle (CPA) with symptoms related to VIII cranial nerve dysfunction. Symptom control was achieved and maintained after single session radiosurgery with gamma knife. Case 2 is a 59-year-old female patient with the history of trigeminal neuralgia secondary to a recurrent ET located in the left CPA. Significant pain improvement was achieved after treatment with gamma knife radiosurgery. Case 3 is a 29-year-old male patient with a CPA ET causing long lasting trigeminal neuralgia, pain relief was achieved in this patient after gamma knife radiosurgery. Long-term symptom relief was achieved in all three cases proving that gamma knife radiosurgery is a good and safe alternative for patients with recurrent or nonsurgically treated ETs.

  19. Self-powered neutron and gamma-ray flux detector

    International Nuclear Information System (INIS)

    Allan, C.J.; Shields, R.B.; Lynch, G.F.; Cuttler, J.M.

    1980-01-01

    A new type of self-powered neutron detector was developed which is sensitive to both the neutron and gamma-ray fluxes. The emitter comprises two parts. The central emitter core is made of materials that generate high-energy electrons on exposure to neutrons. The outer layer acts as a gamma-ray/electron converter, and since it has a higher atomic number and higher back-scattering coefficient than the collector, increases the net outflow or emmission of electrons. The collector, which is around the emitter outer layer, is insulated from the outer layer electrically with dielectric insulation formed from compressed metal-oxide powder. The fraction of electrons given off by the emitter that is reflected back by the collector is less than the fraction of electrons emitted by the collector that is reflected back by the emitter. The thickness of the outer layer needed to achieve this result is very small. A detector of this design responds to external reactor gamma-rays as well as to neutron capture gamma-rays from the collector. The emitter core is either nickel, iron or titanium, or alloys based on these metals. The outer layer is made of platinum, tantalum, osmium, molybdenum or cerium. The detector is particularly useful for monitoring neutron and gamma ray flux intensities in nuclear reactor cores in which the neutron and gamma ray flux intensities are closely proportional, are unltimately related to the fission rate, and are used as measurements of nuclear reactor power. (DN)

  20. GAMMA-CLOUD: a computer code for calculating gamma-exposure due to a radioactive cloud released from a point source

    Energy Technology Data Exchange (ETDEWEB)

    Sugimoto, O [Chugoku Electric Power Co. Inc., Hiroshima (Japan); Sawaguchi, Y; Kaneko, M

    1979-03-01

    A computer code, designated GAMMA-CLOUD, has been developed by specialists of electric power companies to meet requests from the companies to have a unified means of calculating annual external doses from routine releases of radioactive gaseous effluents from nuclear power plants, based on the Japan Atomic Energy Commission's guides for environmental dose evaluation. GAMMA-CLOUD is written in FORTRAN language and its required capacity is less than 100 kilobytes. The average ..gamma..-exposure at an observation point can be calculated within a few minutes with comparable precision to other existing codes.