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Sample records for 106ru 141ce 144ce

  1. An experimental study of the time dependence of uptake from soil of 137Cs, 106Ru, 144Ce and 99Tc into green vegetables, wheat and potatoes

    International Nuclear Information System (INIS)

    In this study the experimental data were analysed using the CEGB's dynamic foodchain model, and were used to validate the relevant part of the model structure, to produce model-specific input data and to identify possible future improvements to the model structure. The root uptake of the specified radionuclides was studied and the concentration levels measured. The data were analysed using a simplified version of the general model. The compartment system incorporated within the model was shown to be capable of reproducing the data for 137Cs, 106Ru and 144Ce to an extent sufficient to justify its use in ingestion radiological dose assessments, but to be less successful in fitting the 99Tc data. The analysis resulted in the production of a well validated set of model-specific input data relevant to UK conditions and agricultural practice differing significantly from values obtained from global literature surveys. Possible future improvements to the model structure were also identified, aimed at providing improved estimates of crop contamination levels for timescales in excess of those considered in this study. (U.K.)

  2. The 144Ce source for SOX

    Science.gov (United States)

    Durero, M.; Vivier, M.; Agostini, M.; Altenmüller, K.; Appel, S.; Bellini, G.; Benziger, J.; Berton, N.; Bick, D.; Bonfini, G.; Bravo, D.; Caccianiga, B.; Calaprice, F.; Caminata, A.; Cavalcante, P.; Chepurnov, A.; Choi, K.; Cribier, M.; D'Angelo, D.; Davini, S.; Derbin, A.; Di Noto, L.; Drachnev, I.; Etenko, A.; Farinon, S.; Fischer, V.; Fomenko, K.; Franco, D.; Gabriele, F.; Gaffiot, J.; Galbiati, C.; Ghiano, C.; Giammarchi, M.; Goeger-Neff, M.; Goretti, A.; Gromov, M.; Hagner, C.; Houdy, T.; Hungerford, E.; Ianni, Aldo; Ianni, Andrea; Jonqueres, N.; Jedrzejczak, K.; Kaiser, M.; Kobychev, V.; Korablev, D.; Korga, G.; Kornoukhov; Kryn, D.; Lachenmaier, T.; Lasserre, T.; Laubenstein, M.; Lehnert, B.; Link, J.; Litvinovich, E.; Lombardi, F.; Lombardi, P.; Ludhova, L.; Lukyanchenko, G.; Machulin, I.; Manecki, S.; Maneschg, W.; Marcocci, S.; Maricic, J.; Mention, G.; Meroni, E.; Meyer, M.; Miramonti, L.; Misiaszek, M.; Montuschi, M.; Muratova, V.; Musenich, R.; Neumair, B.; Oberauer, L.; Obolensky, M.; Ortica, F.; Pallavicini, M.; Papp, L.; Perasso, L.; Pocar, A.; Ranucci, G.; Razeto, A.; Re, A.; Romani, A.; Roncin, R.; Rossi, N.; Schönert, S.; Scola, L.; Semenov, D.; Simgen, H.; Skorokhvatov, M.; Smirnov, O.; Sotnikov, A.; Sukhotin, S.; Suvorov; Tartaglia, R.; Testera, G.; Thurn, J.; Toropova, M.; Veyssiére, C.; Unzhakov, E.; Vogelaar, R. B.; von Feilitzsch, F.; Wang, H.; Weinz, S.; Winter, J.; Wojcik, M.; Wurm, M.; Yokley, Z.; Zaimidoroga, O.; Zavatarelli, S.; Zuber, K.; Zuzel, G.

    2016-02-01

    The SOX (Short distance neutrino Oscillations with BoreXino) project aims at testing the light sterile neutrino hypothesis. To do so, two artificials sources of antineutrinos and neutrinos respectively will be consecutively deployed at the Laboratori Nazionali del Gran Sasso (LNGS) in close vicinity to Borexino, a large liquid scintillator detector. This document reports on the source production and transportation. The source should exhibit a long lifetime and a high decay energy, a requirement fullfilled by the 144Ce-144Pr pair at secular equilibrium. It will be produced at FSUE “Mayak” PA using spent nuclear fuel. It will then be shielded and packed according to international regulation and shipped to LNGS across Europe. Knowledge of the Cerium antineutrino generator (CeANG) parameters is crucial for SOX as it can strongly impact the experiment sensitivity. Several apparatuses are being used or designed to characterize CeANG activity, radioactive emission and content. An overview of the measurements performed so far is presented here.

  3. Absolute standardization of 106Ru by anti-coincidence method

    International Nuclear Information System (INIS)

    The system of absolute standardization activity of radionuclide by anti-coincidence counting and live-time techniques was implemented at LNMRI in 2008 to reduce the impacts of some influence factors in the determination of the activity with coincidence counting technique used for decades in the lab, for example, the measurement time. With the anti-coincidence system, the variety of radionuclides that can be calibrated by LNMRI was increased, in relation to the type of decay. The objective of this work is the standardization of 106Ru by the method of counting anti-coincidence and estimate its measurement uncertainties. (author)

  4. Clinical quality assurance for 106Ru ophthalmic applicators

    International Nuclear Information System (INIS)

    Background and purpose: Episcleral brachytherapy using 106Ru/106Rh ophthalmic applicators is a proven method of therapy of uveal melanomas sparing the globe and in many cases sparing the vision. In the year 2001, an internal clinical quality assurance procedure revealed that part of the ophthalmic applicators leaked and that the calibration was erroneous. Consequently, the producer modernized its production procedures and, in May 2002, introduced a dose rate calibration that is traceable to the NIST standard. This NIST calibration confirmed that the previous calibration had been incorrect. In order to study the effects of the producer's new internal quality assurance procedures on the ophthalmic applicators, applicators of this new generation were submitted to a newly improved internal clinical acceptance test. Patients and methods: The internal clinical acceptance test consists of a leakage test and a dosimetric test of the ophthalmic applicators. The leakage test simulates contact of the ophthalmic applicators with chloride containing body fluid. The dosimetric tests measure depth dose curves and dose rate with a plastic scintillator dosimetric system and compare them with the indications in the producer's certificate. Furthermore, the depth dose profile of the most frequently used applicator (type CCB) was compared with published data. Results: The internal clinical leakage test showed that all of the tested ophthalmic applicators belonging to the new generation (n=17) were tight and not contaminated. The dosimetric acceptance tests applied to seven different types of applicators revealed that the relative depth dose profiles in the therapeutically relevant range (up to a depth of ≤7 mm) deviate from the producer's indications only by -2.7 to +3.2%. The acceptance test of the dose rate values of the ophthalmic applicators at a distance of 2 mm from the surface of the applicators resulted in a coefficient of variation of 1.7% (n=17). In the evaluation of the

  5. Toxicity of 144Ce inhaled in a relatively insoluble form by immature Beagle dogs. XVII

    International Nuclear Information System (INIS)

    Immature Beagle dogs (3-mo old) received a single, brief inhalation exposure to 144Ce in fused aluminosilicate particles as part of a series of studies designed to study the effects of age on dose response relationships for inhaled radionuclides. Forty-nine dogs inhaled graded levels of 144Ce that resulted in initial lung burdens ranging from 0.004-140 μCi/kg 0.15-5200 kBq/kg) body weight. Five control dogs inhaled nonradioactive fused aluminosilicate particles. Forty-one of the 144Ce-exposed dogs have died: 11 with lung tumors 4 with tumors of the tracheobronchial lymph nodes, with a nasal cavity tumor, and 9 with non neoplastic diseases of the respiratory tract. Observations are continuing on the 8 144Ce-exposed dogs that are surviving at this time. (author)

  6. Numerical calculation of relative dose rates from spherical 106Ru beta sources used in ophthalmic brachytherapy

    Science.gov (United States)

    de Paiva, Eduardo

    Concave beta sources of 106Ru/106Rh are used in radiotherapy to treat ophthalmic tumors. However, a problem that arises is the difficult determination of absorbed dose distributions around such sources mainly because of the small range of the electrons and the steep dose gradients. In this sense, numerical methods have been developed to calculate the dose distributions around the beta applicators. In this work a simple code in Fortran language is developed to estimate the dose rates along the central axis of 106Ru/106Rh curved plaques by numerical integration of the beta point source function and results are compared with other calculated data.

  7. Shortcomings of the industrial quality assurance of 106Ru ophthalmic plaques

    International Nuclear Information System (INIS)

    Background: Beta emitting 106Ru applicators manufactured by Bebig GmbH (Berlin, Germany) are widely used to treat intraocular tumors. The applicators are fixed to the bulbus and removed after several days. The following therapy relevant defects have been detected by an internal clinical acceptance test: risk of leakage and inconsistent dose-rate specifications by the manufacturer. In the meantime, components of the internal clinical acceptance test have been adopted successfully by the manufacturer of the 106Ru ophthalmic plaques. Material and Method: 106Ru ophthalmic plaques were tested with the following internal clinical acceptance tests: visual inspection, surface contamination, leakage, and dose-rate verification. The surface contamination test consists of a wet wipe test at moderate pressure. For the leakage test of the 106Ru ophthalmic plaques a clinically relevant scenario was developed in which the contact of the applicator with human tissue is simulated. In the course of it the applicator is inserted into Ringer's solution for several days. The certified energy dose-rate statements of the manufacturer are examined with a 1 mm3 plastic scintillator for consistency. (orig.)

  8. Internal clinical acceptance test of the dose rate of 106Ru/106Rh ophthalmic applicators

    International Nuclear Information System (INIS)

    For the last forty years or so, episcleral brachytherapy using 106Ru/106Rh ophthalmic applicators has been a proven method of therapy for uveal melanomas, sparing the globe and in many cases conserving the vision. In episcleral brachytherapy, a radioactive 106Ru/106Rh ophthalmic applicator (BEBIG Co., Berlin, Germany) is temporarily fixed on the surface of the bulbus oculi, whereby the intraocular tumour gets irradiated protractedly through the sclera. 106Ru/106Rh ophthalmic applicators are primarily beta sources, i.e. they generate a local dose escalation both in the vessels supplying the tumour and in the tumour itself, while simultaneously sparing the risk structures. In its certificates, BEBIG, the manufacturer of the product, indicates a dose rate for the 106Ru/106Rh ophthalmic applicators at a dose specification reference point which ensures traceability to the NIST standard (12/2001). The dose specification reference point is situated at a distance of 2 mm from the middle of the inner (concave) surface of the applicators, and the dose rate was measured with a scintillation detector (diameter 1 mm, height 0.5 mm). The manufacturer indicates for this dose rate at the dose specification reference point a relative measurement uncertainty of ±20% within the 95% confidence interval. Since the introduction of the NIST calibration, the quality of the calibration passed on by BEBIG to the user has been examined for n=45 ophthalmic applicators

  9. Absolute standardization of {sup 106}Ru by anti-coincidence method; Padronizacao absoluta do {sup 106}Ru pelo metodo de anticoincidencia

    Energy Technology Data Exchange (ETDEWEB)

    Silva, C.J. da; Poledna, R.; Tahuata, L., E-mail: eduarda.rezende@ifrj.edu.br [Instituto de Radioprotecao e Dosimetria (IRD/CNEN-RJ/LNMRI), Rio de Janeiro, RJ (Brazil). Lab. Nacional de Metrologia das Radiacoes Ionizantes; Rezende, E.A.; Lopes, R.T. [Coordenacao dos Programas de Pos-Graducacao em Engenharia (LIN/PEN/COPPE/UFRJ), Rio de Janeiro, RJ (Brazil)

    2015-07-01

    The system of absolute standardization activity of radionuclide by anti-coincidence counting and live-time techniques was implemented at LNMRI in 2008 to reduce the impacts of some influence factors in the determination of the activity with coincidence counting technique used for decades in the lab, for example, the measurement time. With the anti-coincidence system, the variety of radionuclides that can be calibrated by LNMRI was increased, in relation to the type of decay. The objective of this work is the standardization of {sup 106}Ru by the method of counting anti-coincidence and estimate its measurement uncertainties. (author)

  10. Internal Clinical Acceptance Test of the Dose Rate of 106Ru/106Rh Ophthalmic Applicators

    International Nuclear Information System (INIS)

    Episcleral brachytherapy using 106Ru/106Rh ophthalmic applicators is a proven method of therapy for uveal melanomas, sparing the globe and in many cases, conserving vision. In its certificates, Bebig, the manufacturer of the product, indicates a dose rate for the 106Ru/106Rh ophthalmic applicators which ensures traceability to the NIST standard (12/2001). Since the introduction of the NIST calibration, the quality of the calibration provided by Bebig to the clinical user has been examined for 45 ophthalmic applicators with a plastic scintillator measurement system. Of these, 20 ophthalmic applicators had a dose rate at the dose specification reference point that exceeded the dose rate stated in the manufacturer's certificate by up to 23%. (author)

  11. The uptake of 90Sr, 137Cs and 144Ce by leaves of spring wheat and rape

    International Nuclear Information System (INIS)

    The distribution and accumulation of 90Sr, 137Cs, 144Ce through the leaf surface into the plant have been studied. The results show that the uptake rate of 137Cs by crop plant is about 53%, while the uptake rate for 90Sr and 144Ce is about 0.4%. However 90Sr is absorbed in significant amount from soil whereas 137Cs is absorbed in negligible amount

  12. Development of a phantom and assessment of (141)Ce as a surrogate radionuclide for flood field uniformity testing of gamma cameras.

    Science.gov (United States)

    Saxena, Sanjay Kumar; Kumar, Yogendra; Malpani, Basant; Rakshit, Sutapa; Dash, Ashutosh

    2016-06-01

    This paper describes an indigenous method for development and deployment of rechargeable liquid filled phantom with newly proposed radionuclide (141)Ce for determination of extrinsic uniformity of gamma cameras. Details about design of phantom, neutron irradiation of cerium targets, chemical processing of (141)Ce, charging of phantom with (141)Ce solution and their performance evaluation are presented. Suitability of (141)Ce in quality assurance of gamma cameras used in in-vivo diagnostic imaging procedures has been amply demonstrated. PMID:27031297

  13. Conceptus uptake of the sup 106 RuNO-nitro complex in relation to gestational stages

    Energy Technology Data Exchange (ETDEWEB)

    Nishimura, Yoshikazu; Inaba, Jiro; Watari, Kazuo (National Inst. of Radiological Sciences, Chiba (Japan)); Matsusaka, Naonori

    1990-03-01

    {sup 106}RuNO-nitro complex was administered intravenously to pregnant rats to study uptake of the radioruthenium complex by the conceptus in relation to gestational stages. Each conceptus was sampled periodically with respect to its placenta, fetal membrane, fetal fluid and fetus. Perceptible radioactivity in the fetus was detected only in the later stage of gestation and its relative concentration, defined as the ratio radioactivity per unit weight in the body tissue at sacrifice to that in the whole-body at dosing, was very low compared with other tissues. The average number of fetuses in one litter was 13 and the transfer rate of nitro complex into the fetuses 24 hr after injection to rats on the 20th day of gestation was about 1% of initial maternal dose. The relative concentration in the placenta and fetal membrane was much higher than in the fetus and decreased with time after injection. These results indicate that the placenta and fetal membrane play significant roles as barriers to the transfer of {sup 106}RuNO-nitro complex into the fetus. (author).

  14. On the actual state of industrial quality assurance procedures with regard to 106Ru ophthalmic plaques

    International Nuclear Information System (INIS)

    In the year 2002, Bebig updated, among other things, the ASMW (GDR) calibration of the dose rate of the 106Ru ophthalmic plaques from the years 1987-1989 by a calibration of the NIST (USA). The current NIST calibration, together with the new equipment for the measurement of the depth dose curves, led to the consequence that the new NIST 2001 dose rate values show, in the mean, a deviation of 0.75 times (plaque type CCC) up to 2.06 times (plaque types CCX, CCY, and CCZ) compared to the dose rate values that had been indicated so far in Bebig's certificate, based on the ASMW 1987 calibration. For the 95% confidence interval, Bebig estimated the measurement uncertainty to be ± 25%. If one takes into consideration the minimal and maximal values in such 95% confidence intervals, it follows that the new NIST 2001 dose rate values deviate between 0.56 times (plaque type CCC) and 2.58 times (plaque types CCX, CCY, and CCZ) from the Bebig certificate (ASMW calibration 1987). As regards leakage, no objections arose in the case of the 106Ru ophthalmic plaques produced according to the new quality standards. (orig.)

  15. Effects of inhaled 144Ce on cardiopulmonary function and histopathology of the dog

    International Nuclear Information System (INIS)

    Twelve dogs inhaled single doses of relatively insoluble particles containing 144Ce and six dogs inhaled particles containing stable cerium as controls. Pulmonary function, clinical, and radiographic evaluations were performed serially. The dogs developed progressive radiation pneumonitis and pulmonary fibrosis similar to that previously reported for whole-lung irradiation from internal or external sources. Focal histologic changes in bronchioles and alveoli were detected functionally during treadmill and tube-breathing stresses at a time when the dogs' clinical and radiographic appearances were normal. Moderate functional impairment was associated with more severe inflammatory and proliferative changes in airways and alveoli. Severe impairment resulted from progressive fibrosis and scarring. These were several strong correlations between functional indices and histological scores. There was a nonlinear relationship between cumulative radiation dose and effects, and once the functional alterations became clinically evident, the disease progressed with little further increase in dose

  16. Assessment, modelization and analysis of 106 Ru experimental transfers through a freshwater trophic system

    International Nuclear Information System (INIS)

    Experiments are carried out in order to study 106 RU transfers through a freshwater ecosystem including 2 abiotic compartments (water and sediment) and 3 trophic levels (10 species). Experimental results are expressed mathematically so as they can be included into a global model which is then tested in two different situations. The comparison of the available data concerning the in situ measured concentrations to the corresponding calculated ones validates the whole procedure. Analysis of the so validated results lightens ruthenium distribution process in the environment. The rare detection of this radionuclide in organisms living in areas contaminated by known meaningful releases can be explained by a relativity high detection limit and by a slight role of the sediment as a secondary contamination source. (author). 78 figs., 18 tabs

  17. Responses of different dosemeters in beta dosimetry of 106Ru/106Rh ophthalmic applicators

    International Nuclear Information System (INIS)

    This work presents the TL response of three kinds of dosimeters from different manufacturing characteristics under irradiation of 106 Ru / 106 Rh sealed sources used in ophthalmic brachytherapy. They are: Ca SO4:Dy + teflon (D- Ca SO4:Dy -0,4), LiF:Mg, Ti (TLD-100) and Ca SO4:Dy (TLD-900). Some of reports accepted by scientific community (NCS report 14 e ICRU report 72) as reference in the quality control of beta applicators dosimetry recommend that the absorbed dose standard uncertainties can be kept below 20%. The TLD Ca SO4:Dy + teflon presented proper sensibility and high precision comparing with the others. Considering the similar dimensions of ophthalmic tumors and aside critical structures it is relevant to reduce undesirable effects due to the irradiation of these structures. Therefore, the quality control in the beta dosimetry using this kind of source is a constant challenge. (author)

  18. Monte Carlo calculation of dose to water of a 106Ru COB-type ophthalmic plaque

    International Nuclear Information System (INIS)

    The concave eye applicators with 106Ru/106Rh or 90Sr/90Y beta-ray sources are worldwide used in brachytherapy for treating intraocular tumors. It raises the need to know the exact dose delivered by beta radiation to tumors but measurement of the dose to water (or tissue) is very difficult due to short range of electrons. The Monte Carlo technique provides a powerful tool for calculation of the dose and dose distributions which helps to predict and determine the doses from different shapes of various types of eye applicators more accurately. The Monte Carlo code MCNPX has been used to calculate dose distributions from a COB-type 106Ru/106Rh ophthalmic applicator manufactured by Eckert and Ziegler BEBIG GmbH. This type of a concave eye applicator has a cut-out whose purpose is to protect the eye nerve which makes the dose distribution more complicated. Several calculations have been performed including depth dose along the applicator central axis and various dose distributions. The depth dose along the applicator central axis and the dose distribution on a spherical surface 1 mm above the plaque inner surface have been compared with measurement data provided by the manufacturer. For distances from 0.5 to 4 mm above the surface, the agreement was within 2.5% and from 5 mm the difference increased from 6% up to 25% at 10 mm whereas the uncertainty on manufacturer data is 20% (2s). It is assumed that the difference is caused by nonuniformly distributed radioactivity over the applicator radioactive layer

  19. Process optimization for effective column separation of 106Ru from aqueous waste associated with spent reprocessing solvent in storage tanks

    International Nuclear Information System (INIS)

    The present work deals with another waste stream resulting from reprocessing operations, viz. the aqueous solution present in substantial quantities as the bottom layer in tanks storing spent TBP-dodecane solvent. The effective separation of 106Ru from aqueous waste streams generated during reprocessing of spent nuclear fuel is difficult because of its complex aqueous chemistry

  20. Effect of fasting on the transit time of 144Ce in the mouse gut

    International Nuclear Information System (INIS)

    Our work with G.I. absorption of actinide elements indicates greater absorption by fasted animals than by animals on regular diets (Weiss and Walburg, undated). Residence time of a metallic compound in the gut may be an important factor influencing G.I. absorption. Cerium-144 (III) chloride was administered by gavage to fasted mice and to mice on regular feed. The G.I. tract was excised, cut into sections, and the activity of each section determined as a function of time after dosing. Our results indicate rapid transit of 144CeCl3 along the empty mouse gut. One hour after dosing, about half the Ce is in the cecal contents; about 40% remains in stomach contents. Twelve hours after dosing, only about 2% remains in the cecum; by 16 hours, almost the entire dose has been cleared from the intestine. Transit times in mice with stomach and intestines containing food were 12 hours longer than in fasted mice. These results lead to the conclusion that factors other than G.I. residence time determine G.I. absorption of actinides in mice

  1. 129I, 60Co, and 106Ru measurements on water samples from the Hanford project environs

    International Nuclear Information System (INIS)

    Groundwater flow and contamination patterns beneath the Hanford project reservation have been studied since the early days of the project. The measurement of radioactive materials at concentrations much below those required for radiation protection are useful for tracing groundwater movement and detection of potential contamination problems before they are apt to occur. Groundwater samples from a number of wells on or near the Hanford reservation have been analyzed for 129I by neutron activation analysis and for gamma radioactivity by low-level coincidence gamma-ray spectrometry. The major radionuclides in addition to natural radioactivity detected in the underground waters by gamma-ray spectrometry were 106Ru and 60Co. Local river and rain water samples were also analyzed for 129I and long-lived radionuclides. Special sample collection methods were developed to prevent contamination of the water samples during collection. Anions travel farther than cations in underground water systems since soils are primarily cation exchangers and retain the cations. Anion exchange techniques were used in the field and the laboratory to recover the desired radionuclides. Sample sizes ranged up to several thousand liters. This paper discusses the sample collection methods,analysis methods, and results obtained. The methods used were found to provide high sensitivity for groundwater studies. (auth)

  2. 134Cs: 137Cs and 106Ru: 137Cs ratios in intertidal sediments from the Cumbria and Lancashire coasts England

    Science.gov (United States)

    Stanners, D. A.; Aston, S. R.

    1981-10-01

    The distributions of 134Cs, 137Cs and 106Ru in intertidal surface sediments from the coasts of Cumbria and Lancashire, north-west England, are reported. The ratios of 134Cs: 137Cs and 106Ru: 137Cs activities have been used together with the isotopic composition of the Windscale radioactive effluents to examine the contamination history of sediments. Distinct differences between the activities and time of contamination of muds, silts and sands are found, and the apparent lag times of transport of radioactive wastes to different sediment localities are estimated. The relatively high activities in fine sediments reflect recent discharges indicating a rapid response to discharge, while the sands contain low levels of older contamination. Apparent lag times of up to 6 years are estimated for the study area; the transport to the south is generally more rapid than to the north. These results have consequences for the operation and interpretation of radiological monitoring in coastal areas.

  3. Assessment of ocular beta radiation dose distribution due to 106Ru/106Rh brachytherapy applicators using MCNPX Monte Carlo code

    Directory of Open Access Journals (Sweden)

    Nilseia Aparecida Barbosa

    2014-08-01

    Full Text Available Purpose: Melanoma at the choroid region is the most common primary cancer that affects the eye in adult patients. Concave ophthalmic applicators with 106Ru/106Rh beta sources are the more used for treatment of these eye lesions, mainly lesions with small and medium dimensions. The available treatment planning system for 106Ru applicators is based on dose distributions on a homogeneous water sphere eye model, resulting in a lack of data in the literature of dose distributions in the eye radiosensitive structures, information that may be crucial to improve the treatment planning process, aiming the maintenance of visual acuity. Methods: The Monte Carlo code MCNPX was used to calculate the dose distribution in a complete mathematical model of the human eye containing a choroid melanoma; considering the eye actual dimensions and its various component structures, due to an ophthalmic brachytherapy treatment, using 106Ru/106Rh beta-ray sources. Two possibilities were analyzed; a simple water eye and a heterogeneous eye considering all its structures. Two concave applicators, CCA and CCB manufactured by BEBIG and a complete mathematical model of the human eye were modeled using the MCNPX code. Results and Conclusion: For both eye models, namely water model and heterogeneous model, mean dose values simulated for the same eye regions are, in general, very similar, excepting for regions very distant from the applicator, where mean dose values are very low, uncertainties are higher and relative differences may reach 20.4%. For the tumor base and the eye structures closest to the applicator, such as sclera, choroid and retina, the maximum difference observed was 4%, presenting the heterogeneous model higher mean dose values. For the other eye regions, the higher doses were obtained when the homogeneous water eye model is taken into consideration. Mean dose distributions determined for the homogeneous water eye model are similar to those obtained for the

  4. Assessment, modelization and analysis of {sup 106} Ru experimental transfers through a freshwater trophic system; Evaluation, modelisation et analyse des transferts experimentaux du {sup 106}Ru au sein d`un reseau trophique d`eau douce

    Energy Technology Data Exchange (ETDEWEB)

    Vray, F.

    1994-11-24

    Experiments are carried out in order to study {sup 106} RU transfers through a freshwater ecosystem including 2 abiotic compartments (water and sediment) and 3 trophic levels (10 species). Experimental results are expressed mathematically so as they can be included into a global model which is then tested in two different situations. The comparison of the available data concerning the in situ measured concentrations to the corresponding calculated ones validates the whole procedure. Analysis of the so validated results lightens ruthenium distribution process in the environment. The rare detection of this radionuclide in organisms living in areas contaminated by known meaningful releases can be explained by a relativity high detection limit and by a slight role of the sediment as a secondary contamination source. (author). 78 figs., 18 tabs.

  5. Responses of different dosemeters in beta dosimetry of {sup 106}Ru/{sup 106}Rh ophthalmic applicators;Respostas de diferentes dosimetros termoluminescentes na dosimetria beta de aplicadores oftalmicos de {sup 106}Ru/{sup 106}Rh

    Energy Technology Data Exchange (ETDEWEB)

    Ferreira, D.F.P.; Daros, K.A.C.; Segreto, R.A.; Medeiros, R.B. [Universidade Federal de Sao Paulo (UNIFESP), Sao Paulo, SP (Brazil)

    2009-07-01

    This work presents the TL response of three kinds of dosimeters from different manufacturing characteristics under irradiation of 106 Ru / 106 Rh sealed sources used in ophthalmic brachytherapy. They are: Ca SO{sub 4}:Dy + teflon (D- Ca SO{sub 4}:Dy -0,4), LiF:Mg, Ti (TLD-100) and Ca SO{sub 4}:Dy (TLD-900). Some of reports accepted by scientific community (NCS report 14 e ICRU report 72) as reference in the quality control of beta applicators dosimetry recommend that the absorbed dose standard uncertainties can be kept below 20%. The TLD Ca SO{sub 4}:Dy + teflon presented proper sensibility and high precision comparing with the others. Considering the similar dimensions of ophthalmic tumors and aside critical structures it is relevant to reduce undesirable effects due to the irradiation of these structures. Therefore, the quality control in the beta dosimetry using this kind of source is a constant challenge. (author)

  6. Process for the removal of 106Ru traces from NH4NO3 effluent generated during recycling of sintered depleted uranium fuel pellets

    International Nuclear Information System (INIS)

    Several chemical treatment formulations were tested for the effective removal of very low levels of 106Ru activity from NH4NO3 effluent generated during wet processing of rejected sintered depleted uranium (DU) fuel pellets. Based on the results, a simple process involving precipitation of cobalt sulphide along with ferric hydroxide was selected and further optimization of process variables was carried out. The optimized process has been found to be highly efficient in reducing 106Ru activity down to extremely low levels. (author)

  7. Energy deposition by a 106Ru/106Rh eye applicator simulated using LEPTS, a low-energy particle track simulation

    International Nuclear Information System (INIS)

    The present study introduces LEPTS, an event-by-event Monte Carlo programme, for simulating an ophthalmic 106Ru/106Rh applicator relevant in brachytherapy of ocular tumours. The distinctive characteristics of this code are the underlying radiation-matter interaction models that distinguish elastic and several kinds of inelastic collisions, as well as the use of mostly experimental input data. Special emphasis is placed on the treatment of low-energy electrons for generally being responsible for the deposition of a large portion of the total energy imparted to matter. - Highlights: → We present the Monte Carlo code LEPTS, a low-energy particle track simulation. → Carefully selected input data from 10 keV to 1 eV. → Application to an electron emitting Ru-106/Rh-106 plaque used in brachytherapy.

  8. Biological alterations resulting from chronic lung irradiation. I. The pulmonary lipid composition, physiology, and pathology after inhalation by beagle dogs of 144Ce-labeled fused clay aerosols

    International Nuclear Information System (INIS)

    Three groups of four beagle dogs inhaled a 144Ce-labeled fused clay aerosol; two additional dogs per group, exposed to a stable cerium-labeled fused clay aerosol, were used as controls. At monthly intervals, one diaphragmatic lobe of each of two dogs exposed to 144Ce and one control animal from each group was lavaged with isotonic saline. The recovered lavage solutions were centrifuged to isolate lung cells (mostly macrophages) and surfactant for lipid analyses. The groups were sacrificed at 2, 4, and 6 mo after exposure, when the lungs of the dogs exposed to 144Ce had average cumulative radiation doses of 23, 36, and 59 krad, respectively. Chronic irradiation of the lung resulted in a progressive radiation pneumonitis which was assessed clinically and pathologically at various intervals. At sacrifice, the lungs were analyzed for 144Ce and the right apical and diaphragmatic lobes were minced and lyophilized and the lipids were extracted. Total lipids from all lung samples were determined gravimetrically and individual compounds were identified, isolated, and quantitated. The quantities of lipid in lung tissue, in pulmonary cells, and in surfactant increased as a function of time and radiation dose. Neutral lipids (sterol esters and triglycerides) accounted for most of the increase. (U.S.)

  9. Multidimensional dosimetry of {sup 106}Ru eye plaques using EBT3 films and its impact on treatment planning

    Energy Technology Data Exchange (ETDEWEB)

    Heilemann, G., E-mail: gerd.heilemann@meduniwien.ac.at; Kostiukhina, N. [Department of Radiation Oncology/Comprehensive Cancer Center, Medical University of Vienna/AKH Vienna, Vienna 1090 (Austria); Nesvacil, N.; Georg, D. [Department of Radiation Oncology/Comprehensive Cancer Center, Medical University of Vienna/AKH Vienna, Vienna 1090, Austria and Christian Doppler Laboratory for Medical Radiation Research for Radiation Oncology, Vienna 1090 (Austria); Blaickner, M. [Health and Environment Department Biomedical Systems, Austrian Institute of Technology GmbH, Vienna 1220 (Austria)

    2015-10-15

    Purpose: The purpose of this study was to establish a method to perform multidimensional radiochromic film measurements of {sup 106}Ru plaques and to benchmark the resulting dose distributions against Monte Carlo simulations (MC), microdiamond, and diode measurements. Methods: Absolute dose rates and relative dose distributions in multiple planes were determined for three different plaque models (CCB, CCA, and COB), and three different plaques per model, using EBT3 films in an in-house developed polystyrene phantom and the MCNP6 MC code. Dose difference maps were generated to analyze interplaque variations for a specific type, and for comparing measurements against MC simulations. Furthermore, dose distributions were validated against values specified by the manufacturer (BEBIG) and microdiamond and diode measurements in a water scanning phantom. Radial profiles were assessed and used to estimate dosimetric margins for a given combination of representative tumor geometry and plaque size. Results: Absolute dose rates at a reference depth of 2 mm on the central axis of the plaque show an agreement better than 5% (10%) when comparing film measurements (MCNP6) to the manufacturer’s data. The reproducibility of depth-dose profile measurements was <7% (2 SD) for all investigated detectors and plaque types. Dose difference maps revealed minor interplaque deviations for a specific plaque type due to inhomogeneities of the active layer. The evaluation of dosimetric margins showed that for a majority of the investigated cases, the tumor was not completely covered by the 100% isodose prescribed to the tumor apex if the difference between geometrical plaque size and tumor base ≤4 mm. Conclusions: EBT3 film dosimetry in an in-house developed phantom was successfully used to characterize the dosimetric properties of different {sup 106}Ru plaque models. The film measurements were validated against MC calculations and other experimental methods and showed a good agreement with

  10. Determination of 106Ru, 134/137Cs, and 241Am concentrations and Action Level in the Foodstuffs Consumed by Inhabitants of Iraq

    Directory of Open Access Journals (Sweden)

    *H. N. Majeed

    2013-03-01

    Full Text Available The specific activity concentrations of (106Ru, 134/137Cs, and 241Am nuclides in 40 imported foodstuffs which collected randomly in January 2012 from all Iraqi cities markets were studied. The rang of specific activity concentrations of 106Ru varies from (37.930±6.16 Bq kg-1 (S No. :17: Turkey Kidney bean to 99.735±9.99 Bq kg-1 (S No.:32: Egypt Broad bean, with average value 71.667±8.47 Bq kg-1. For 134Cs varies from 0.200±0.45 Bq kg-1 (S No. :19 : Ukraine Chick-pea to 2.365±1.54 Bq kg-1 (S No. :33 : Peru Broad bean with average value (0.988±0.99 Bq kg-1.The activity concentrations of 137Cs varies from 0.164±0.40 Bq kg-1 (S No.:19 : Ukraine Chick-pea to 5.291±2.30 Bq kg-1 ( S No.: 39: Uzbekistan Mung bean with average value 1.460±1.21, then for 241Am the activity concentrations varies from 0.029±0.17 Bq kg-1 (S No.:23 : Iran Chick-pea to 1.248±1.12 Bq kg-1 (S No.:40: Canada Green peas with average value 0.399±0.63. All the values were less than the World average concentrations [15,17]. The high contributor for 106Ru, 134/137Cs, and 241Am radionuclides were in Broad bean and other foodstuffs (which contained Brown grit, White grit, Mung bean and Green peas as a 12%, Broad bean as 14%, corn as a 19% and other foodstuffs with 15% respectively The lowest contributor of 106Ru, 134/137Cs, and 241Am radionuclides in the studied foodstuffs were 6% in cowpea, 7% in semolina, 5% in lentil and 4% in lentil respectively. The action level of the 106Ru, 134/137Cs, and 241Am radionuclide’s for three age groups have been calculated and the foodstuffs were within the range permitted and free of any radiation and thus there was no seriousness in dealing with.

  11. Evolution of gamma artificial radioactivity in coastal sediments of the English Channel during the years 1976, 1977 and 1978

    International Nuclear Information System (INIS)

    During 1976-1977, a state of equilibrium was found to prevail for 106Ru and 144Ce, especially in the North-West Cotentin and the Norman-Breton gulf, where reconcentration of both radionuclides was observed with preferential enrichment of the latter over the former. Levels of 125Sb and 137Cs were found to be low but were difficult to interpret, because of the particular physico-chemical behavior of 125Sb and the long half-life of 137Cs. The results obtained for 103Ru, 141Ce, 95Zr may be explained entirely by the contribution of atmospheric fallout. 144Ce and 106Ru levels in the Norman-Breton gulf may be for the most part ascribed to La Hague disposals, radionuclide dispersal from the emissary being characterized by an eastward transfer of the soluble fraction and a westward transfer of the particulate fraction, with transit times which may last up to 2 years. The boundary between the areas submitted respectively to the twofold impact of fallout and industrial waste, and to fallout alone would appear to lie between the mouth of the Trieux river and Morlaix Bay. From a graphic representation of the relationship between radionuclides, empiric distribution laws for 106Ru and 137Cs were established from 144Ce level parameters characteristic of the areas considered (years 1976-1977)

  12. Nondestructive analysis of RA reactor fuel burnup, Program for burnup calculation base on relative yield of 106Ru, 134Cs and 137Cs in the irradiated fuel

    International Nuclear Information System (INIS)

    Burnup of low enriched metal uranium fuel of the RA reactor is described by two chain reactions. Energy balance and material changes in the fuel are described by systems of differential equations. Numerical integration of these equations is base on the the reactor operation data. Neutron flux and percent of Uranium-235 or more frequently yield of epithermal neutrons in the neutron flux, is determined by iteration from the measured contents of 106Ru, 134Cs and 137Cs in the irradiated fuel. The computer program was written in FORTRAN-IV. Burnup is calculated by using the measured activities of fission products. Burnup results are absolute values

  13. Quantitative analysis of fission products by γ spectrography

    International Nuclear Information System (INIS)

    The activity of the fission products present in treated solutions of irradiated fuels is given as a function of the time of cooling and of the irradiation time. The variation of the ratio (144Ce + 144Pr activity)/ 137Cs activity) as a function of these same parameters is also given. From these results a method is deduced giving the 'age' of the solution analyzed. By γ-scintillation spectrography it was possible to estimate the following elements individually: 141Ce, 144Ce + 144Pr, 103Ru, 106Ru + 106Rh, 137Cs, 95Zr + 95Nb. Yield curves are given for the case of a single emitter. Of the various existing methods, that of the least squares was used for the quantitative analysis of the afore-mentioned fission products. The accuracy attained varies from 3 to 10%. (author)

  14. Energy deposition by a {sup 106}Ru/{sup 106}Rh eye applicator simulated using LEPTS, a low-energy particle track simulation

    Energy Technology Data Exchange (ETDEWEB)

    Fuss, M.C. [Instituto de Fisica Fundamental, Consejo Superior de Investigaciones Cientificas (CSIC), Serrano 113-bis, 28006 Madrid (Spain); Munoz, A.; Oller, J.C. [Centro de Investigaciones Energeticas, Medioambientales y Tecnologicas (CIEMAT), Avenida Complutense 22, 28040 Madrid (Spain); Blanco, F. [Departamento de Fisica Atomica, Molecular y Nuclear, Universidad Complutense de Madrid, Avenida Complutense, 28040 Madrid (Spain); Williart, A. [Departamento de Fisica de los Materiales, Universidad Nacional de Educacion a Distancia, Senda del Rey 9, 28040 Madrid (Spain); Limao-Vieira, P. [Laboratorio de Colisoes Atomicas e Moleculares, Departamento de Fisica, CEFITEC, FCT-Universidade Nova de Lisboa, Quinta da Torre, 2829-516 Caparica (Portugal); Borge, M.J.G.; Tengblad, O. [Instituto de Estructura de la Materia, Consejo Superior de Investigaciones Cientificas (CSIC), Serrano 113-bis, 28006 Madrid (Spain); Huerga, C.; Tellez, M. [Hospital Universitario La Paz, Paseo de la Castellana 261, 28046 Madrid (Spain); Garcia, G., E-mail: g.garcia@iff.csic.es [Instituto de Fisica Fundamental, Consejo Superior de Investigaciones Cientificas (CSIC), Serrano 113-bis, 28006 Madrid (Spain); Departamento de Fisica de los Materiales, Universidad Nacional de Educacion a Distancia, Senda del Rey 9, 28040 Madrid (Spain)

    2011-09-15

    The present study introduces LEPTS, an event-by-event Monte Carlo programme, for simulating an ophthalmic {sup 106}Ru/{sup 106}Rh applicator relevant in brachytherapy of ocular tumours. The distinctive characteristics of this code are the underlying radiation-matter interaction models that distinguish elastic and several kinds of inelastic collisions, as well as the use of mostly experimental input data. Special emphasis is placed on the treatment of low-energy electrons for generally being responsible for the deposition of a large portion of the total energy imparted to matter. - Highlights: > We present the Monte Carlo code LEPTS, a low-energy particle track simulation. > Carefully selected input data from 10 keV to 1 eV. > Application to an electron emitting Ru-106/Rh-106 plaque used in brachytherapy.

  15. CeLAND: search for a 4th light neutrino state with a 3 PBq 144Ce-144Pr electron antineutrino generator in KamLAND

    CERN Document Server

    Gando, A; Hayashida, S; Ikeda, H; Inoue, K; Ishidoshiro, K; Ishikawa, H; Koga, M; Matsuda, R; Matsuda, S; Mitsui, T; Motoki, D; Nakamura, K; Oki, Y; Otani, M; Shimizu, I; Shirai, J; Suekane, F; Suzuki, A; Takemoto, Y; Tamae, K; Ueshima, K; Watanabe, H; Xu, B D; Yamada, S; Yamauchi, Y; Yoshida, H; Cribier, M; Durero, M; Fischer, V; Gaffiot, J; Jonqueres, N; Kouchner, A; Lasserre, T; Leterme, D; Letourneau, A; Lhuillier, D; Mention, G; Rampal, G; Scola, L; Veyssiere, Ch; Vivier, M; Yala, P; Berger, B E; Kozlov, A; Banks, T; Dwyer, D; Fujikawa, B K; Han, K; Kolomensky, Yu G; Mei, Y; O'Donnell, T; Decowski, P; Markoff, D M; Yoshida, S; Kornoukhov, V N; Gelis, T V M; Tikhomirov, G V; Learned, J G; Maricic, J; Matsuno, S; Milincic, R; Karwowski, H J; Efremenko, Y; Detwiler, A; Enomoto, S

    2013-01-01

    The reactor neutrino and gallium anomalies can be tested with a 3-4 PBq (75-100 kCi scale) 144Ce-144Pr antineutrino beta-source deployed at the center or next to a large low-background liquid scintillator detector. The antineutrino generator will be produced by the Russian reprocessing plant PA Mayak as early as 2014, transported to Japan, and deployed in the Kamioka Liquid Scintillator Anti-Neutrino Detector (KamLAND) as early as 2015. KamLAND's 13 m diameter target volume provides a suitable environment to measure the energy and position dependence of the detected neutrino flux. A characteristic oscillation pattern would be visible for a baseline of about 10 m or less, providing a very clean signal of neutrino disappearance into a yet-unknown, sterile neutrino state. This will provide a comprehensive test of the electron dissaperance neutrino anomalies and could lead to the discovery of a 4th neutrino state for Delta_m^2 > 0.1 eV^2 and sin^2(2theta) > 0.05.

  16. A Brief Review of Past INL Work Assessing Radionuclide Content in TMI-2 Melted Fuel Debris: The Use of 144Ce as a Surrogate for Pu Accountancy

    Energy Technology Data Exchange (ETDEWEB)

    D. L. Chichester; S. J. Thompson

    2013-09-01

    This report serves as a literature review of prior work performed at Idaho National Laboratory, and its predecessor organizations Idaho National Engineering Laboratory (INEL) and Idaho National Engineering and Environmental Laboratory (INEEL), studying radionuclide partitioning within the melted fuel debris of the reactor of the Three Mile Island 2 (TMI-2) nuclear power plant. The purpose of this review is to document prior published work that provides supporting evidence of the utility of using 144Ce as a surrogate for plutonium within melted fuel debris. When the TMI-2 accident occurred no quantitative nondestructive analysis (NDA) techniques existed that could assay plutonium in the unconventional wastes from the reactor. However, unpublished work performed at INL by D. W. Akers in the late 1980s through the 1990s demonstrated that passive gamma-ray spectrometry of 144Ce could potentially be used to develop a semi-quantitative correlation for estimating plutonium content in these materials. The fate and transport of radioisotopes in fuel from different regions of the core, including uranium, fission products, and actinides, appear to be well characterized based on the maximum temperature reached by fuel in different parts of the core and the melting point, boiling point, and volatility of those radioisotopes. Also, the chemical interactions between fuel, fuel cladding, control elements, and core structural components appears to have played a large role in determining when and how fuel relocation occurred in the core; perhaps the most important of these reaction appears to be related to the formation of mixed-material alloys, eutectics, in the fuel cladding. Because of its high melting point, low volatility, and similar chemical behavior to plutonium, the element cerium appears to have behaved similarly to plutonium during the evolution of the TMI-2 accident. Anecdotal evidence extrapolated from open-source literature strengthens this logical feasibility for

  17. Studies on treatment of low level radioactive liquid waste for removal of anionic species of 125Sb, 99Tc and 106Ru. Contributed Paper RD-14

    International Nuclear Information System (INIS)

    The treatment of intermediate level waste at Waste Immobilization Plant generates low level radioactive waste which would require further management before discharge to sea. This waste is expected to contain polymeric oxo anions of 125Sb, 99Tc, 106Ru in addition to cationic species like 137Cs, 90Sr etc. Chemical treatment takes care of the major contributors to radioactivity viz 137Cs, 90Sr etc but traces of activity due to anionic species remain in the treated waste effluent. Novel composite anionic exchanger namely Polyurethane foam coated with Hydrous Zirconium Oxide was developed for removal of these anionic species. This material was successfully employed for removal of anionic 125Sb from radioactive waste effluent at Waste Management Division, Trombay. Based on our experience with Sb removal using the above material it was decided to assess the ability of the exchanger in removal of other anionic species bearing Ru and Tc. It was observed that in addition to complete removal of Sb, 50% Ru removal and 40% Tc could also be removed using this material from radioactive waste effluents. In lab experiments, similar results were obtained with simulated low level waste bearing inactive Ru. Among several hydrous oxides tried in a batch study, Hydrous Zirconium Oxide showed a maximum removal of 40% for Tc in actual waste generated from reprocessing plant. Based on the above it has been planned to set up an anion exchange column with Hydrous Zirconium Oxide coated Polyurethane foam for final treatment of chemically treated waste effluent prior to discharge as a prime step towards achieving our goal of minimum discharge to Sea. (author)

  18. Determination of absorbed dose distribution in water for COC ophthalmic applicator of {sup 106}Ru/{sup 106}Rh using Monte Carlo code-MCNPX; Determinacao da distribuicao de dose absorvida na agua para o aplicador oftalmico COC de {sup 106}Ru/{sup 106}Rh utilizando o codigo de Monte Carlo - MCNPX

    Energy Technology Data Exchange (ETDEWEB)

    Barbosa, Nilseia A.; Rosa, Luiz A. Ribeiro da, E-mail: nilseia@ird.gov.br, E-mail: lrosa@ird.gov.br [Instituto de Radioprotecao e Dosimetria (IRD/CNEN-RJ),Rio de Janeiro, RJ (Brazil); Braz, Delson, E-mail: delson@nuclear.ufrj.br [Coordenacao dos programas de Pos-Graduacao em Engenharia (PEN/COPPE/UFRJ), Rio de Janeiro, RJ (Brazil). Programa de Engenharia Nuclear

    2014-07-01

    The COC ophthalmic applicators using beta radiation source of {sup 106}Ru/{sup 106}Rh are used in the treatment of intraocular tumors near the optic nerve. In this type of treatment is very important to know the dose distribution in order to provide the best possible delivery of prescribed dose to the tumor, preserves the optic nerve region extremely critical, that if damaged, can compromise the patient's visual acuity, and cause brain sequelae. These dose distributions are complex and doctors, who will have the responsibility on the therapy, only have the source calibration certificate provided by the manufacturer Eckert and Ziegler BEBIG GmbH. These certificates provide 10 absorbed dose values at water depth along the central axis applicator with the uncertainties of the order of 20% isodose and in a plane located 1 mm from the applicator surface. Thus, it is important to know with more detail and precision the dose distributions in water generated by such applicators. To this end, the Monte Carlo simulation was used using MCNPX code. Initially, was validated the simulation by comparing the obtained results to the central axis of the applicator with those provided by the certificate. The different percentages were lower than 5%, validating the used method. Lateral dose profile was calculated for 6 different depths in intervals of 1 mm and the dose rates in mGy.min{sup -1} for the same depths.

  19. Appendix to Health and Safety Laboratory environmental quarterly, March 1, 1976--June 1, 1976. [Tabulated data on content of lead in surface air and /sup 7/Be, /sup 95/Zr, /sup 137/Cs, /sup 144/Ce, and /sup 90/Sr in surface air, milk, drinking water, and foods sampled in USA

    Energy Technology Data Exchange (ETDEWEB)

    Hardy, E.P. Jr.

    1976-07-01

    Tabulated data are presented on: the monthly deposition of /sup 89/Sr and /sup 90/Sr at some 100 world land sites; the content of lead and /sup 7/Be, /sup 95/Zr, /sup 137/Cs, and /sup 144/Ce in samples of surface air from various world sites; and the content of /sup 90/Sr in samples of milk, drinking water, and animal and human diets collected at various locations throughout the USA. (CH)

  20. Standard test method for gamma energy emission from fission products in uranium hexafluoride and uranyl nitrate solution

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2005-01-01

    1.1 This test method covers the measurement of gamma energy emitted from fission products in uranium hexafluoride (UF6) and uranyl nitrate solution. It is intended to provide a method for demonstrating compliance with UF6 specifications C 787 and C 996 and uranyl nitrate specification C 788. 1.2 The lower limit of detection is 5000 MeV Bq/kg (MeV/kg per second) of uranium and is the square root of the sum of the squares of the individual reporting limits of the nuclides to be measured. The limit of detection was determined on a pure, aged natural uranium (ANU) solution. The value is dependent upon detector efficiency and background. 1.3 The nuclides to be measured are106Ru/ 106Rh, 103Ru,137Cs, 144Ce, 144Pr, 141Ce, 95Zr, 95Nb, and 125Sb. Other gamma energy-emitting fission nuclides present in the spectrum at detectable levels should be identified and quantified as required by the data quality objectives. 1.4 This standard does not purport to address all of the safety concerns, if any, associated with its us...

  1. Reconstruction of the composition of the Chernobyl radionuclide fallout and external radiation absorbed doses to the population in areas of Russia

    International Nuclear Information System (INIS)

    The results of reconstruction of the radionuclide composition of the Chernobyl fallout in the territories of Russia is presented. Reconstruction has been carried out by means of statistical analysis of the gamma spectrometry data on 2867 soil samples collected in the territories of Ukraine, Byelarus and Russia from 1986 to 1988. To verify the data, aggregated estimates of the fuel composition of the 4th block at the moment of the accident (available from the literature) have been used, as well as the estimates of activity released to the atmosphere. As a result, correlation and regression dependences have been obtained between the activities of the radionuclides most contributing to the dose (137Cs, 134Cs, 131I, 140Ba, 140La, 95Zr, 95Nb, 103Ru, 106Ru, 141Ce, 144Ce, 125Sb). Statistically significant regression relations between different pairs of radionuclides (including analysis of the 'noise' contribution to the data) depending on the distance between the point of sample collection and the power station are presented for the 'north-east track' - the northern part of the 30 km zone and southern part of the Gomel 'district (Byelarus) and the Briansk, Kaluga, Tula and Orel districts (Russia). A methodology is also described for reconstructing space-time characteristics of the contamination of the territories by major dose-forming radionuclides released from the Chernobyl NPP 4th unit. (Author)

  2. Biological effects of radiation: The induction of malignant transformation and programmed cell death

    International Nuclear Information System (INIS)

    In the Chernobyl explosions and fire, powderized nuclear fuel was released from the reactor core, causing an unexpected fallout. X-ray analysis and scanning electron microscopy showed that the isolated single particles were essentially pure uranium. These uranium aerosols contained all of the nonvolatile fission products, including the b-emitters, 95Zr, 103Ru, 106Ru, 141Ce, and 144Ce. The hot particles are extremely effective in inducing malignant transformation in mouse fibroblast cells in vitro. The major factor responsible for this effect is focus promotion caused by a wound-mediated permanent increase in cell proliferation (mitogenesis associated with mutagenesis). Transformed foci were analysed for the activation of c-abl, c-erb-A, c-erb-B, c-fms, c-fos, c-myb, c-myc, c-Ha-ras, c-Ki-ras, c-sis, and c-raf oncogenes at the transcriptional level. The pattern of oncogene activation was found to vary from focus to focus. Long interspersed repeated DNA (L1 or LINE makes up a class of mobile genetic elements which can amplify in the cell genome by retroposition. This element is spontaneously transcriptionally activated at a critical population density and later amplified in rat chloroleukaemia cells. UV light and ionizing radiation induce this activation prematurely, and the activation is followed by programmed cell death (apoptosis) in a sequence of events identical to that seen in LIRn activation occurring spontaneously

  3. Pollution of atmospheric air with toxic and radioactive particulate matter investigated by means of nuclear techniques

    International Nuclear Information System (INIS)

    The application of spectrometric methods of nuclear techniques to the investigations of atmospheric air pollution by toxic and radioactive elements and results of these investigations conducted in the highly industrialized and urbanized regions of Poland have been presented. The method of precipitation of the samples, the measurements and analysis of radiation spectra of alpha and gamma radiation emitted by isotopes present in the samples have been described. The concentrations of toxic metal dust in the air have been evaluated by neutron activation and X-ray fluorescence analysis. Appropriate methods of measurement, calibration of instrument and the discussion of results have been presented. The work presents the results of investigations performed in Siersza within the years 1973-1974 and in Warsaw in the period of 1975-1977, which have permitted to estimate the mean monthly values of concentration in the atmospheric air of the following radioisotopes: 7Be, 54Mn, 95Zr, 103Ru, 106Ru, 125Sb, 131I, 137Cs, 140Ba, 141Ce, 144Ce, 226Ra, Th-nat, U-nat and the following stable elements: Sc, Cr, Fe, Co, Zn, As, Se, Sb, W, Pb. The analysis of changes in concentration of each particular artificial radioisotope in the air for the region of Poland in connection with Chinese nuclear explosions have been given. On the basis of the performed environmental investigations the method of analysis of relations between the concentrations of particular elements present in the dust has been discussed. The applications of this method have been presented. The hazard to the population and the environment caused by the radioactive and toxic dust present in the atmospheric air has been estimated. (author)

  4. Yield-Energy Dependence for 147Nd and 144Ce Under Strong Neutron Field

    Institute of Scientific and Technical Information of China (English)

    QIAN; Jing; LIU; Ting-jin; SUN; Zheng-jun; SHU; Neng-chuan

    2012-01-01

    <正>The data of the fission product yield play an important role in the nuclear science technology and nuclear engineering because they are the key data in the calculation of the decay heat, shield design, nuclear verification, radiochemistry reprocessing and nuclear safety, etc. Especially, it is the essential data in fission power estimation for a fission device. It is well known that there exists a consecutive neutron spectrum with the energy from 1 keV to 15 MeV for a fission-fusion device. So in order to estimate the

  5. Sorption of radionuclides from Pb-Bi melt. Report 1

    International Nuclear Information System (INIS)

    Results of laboratory investigations of sorption and interfacial distribution of 54Mn, 59Fe, 60Co, 106Ru, 125Sb, 137Cs, 144Ce, 154,155Eu and 235,238U radionuclides in the system Pb-Bi melt - steel surface are analyzed. It is shown that 106Ru and 125Sb are concentrated in Pb-Bi melt and other radionuclides with higher oxygen affinity are sorbed on oxide deposits on structural materials. Temperature dependences of sorption efficiency of radionuclides are studied. It is shown that there is sharp increase of this value for all radionuclides near the temperature range 350-400 deg C. Recommendations are given on the use of 106Ru and 125Sb as a reference for fuel element rupture detection system with radiometric monitoring of coolant melt samples and 137Cs, 134Cs, 134mCs with radiometric monitoring of sorbing samples

  6. Radionuclides contamination of fungi after accident on the Chernobyl NPP

    Energy Technology Data Exchange (ETDEWEB)

    Zarubina, Nataliia E.; Zarubin, Oleg L. [Institute for Nuclear Research of National Academy of Sciense, 03680, pr-t Nauki, 47, Kiev (Ukraine)

    2014-07-01

    Accumulation of radionuclides by the higher fungi (macromycetes) after the accident on the Chernobyl atomic power plant in 1986 has been studied. Researches were spent in territory of the Chernobyl alienation zone and the Kiev region. Our research has shown that macromycetes accumulate almost all types of radionuclides originating from the accident ({sup 131}I, {sup 140}Ba /{sup 140}La, {sup 103}Ru, {sup 106}Ru, {sup 141}Ce, {sup 144}Ce, {sup 95}Nb, {sup 95}Zr, {sup 137}Cs and {sup 134}Cs). They accumulate the long-living {sup 90}Sr in much smaller (to 3 - 4 orders) quantities than {sup 137}Cs. We have established existence of two stages in accumulation of {sup 137}Cs by higher fungi after the accident on the Chernobyl NPP: the first stage resides in the growth of the concentration, the second - in gradual decrease of levels of specific activity of this radionuclide. Despite reduction of {sup 137}Cs specific activity level, the content of this radionuclide at testing areas of the 5-km zone around the Chernobyl NPP reaches 1,100,000 Bq/kg of fresh weight in 2013. We investigated dynamics of accumulation of Cs-137 in higher fungi of different ecological groups. One of the major factors that influence levels of accumulation of {sup 137}Cs by fungi is their nutritional type (ecological group). Fungi that belong to ecological groups of saprotrophes and xylotrophes accumulate this radionuclide in much smaller quantities than symbio-trophic fungi. As a result of the conducted research it has been established that symbio-trophic fungi store more {sup 137}Cs than any other biological objects in forest ecosystems. Among the symbio-trophic fungi species, species showing the highest level of {sup 137}Cs contamination vary in different periods of time after the deposition. It is connected with variability of quantities of these radio nuclides accessible for absorption at the depth of localization of the main part of mycelium of each species in a soil profile. Soil contamination

  7. Fission product release from ZrC-coated fuel particles during postirradiation heating at 1600 C

    International Nuclear Information System (INIS)

    Release behavior of fission products from ZrC-coated UO2 particles was studied by a postirradiation heating test at 1600 C (1873 K) for 4500 h and subsequent postheating examinations. The fission gas release monitoring and the postheating examinations revealed that no pressure vessel failure occurred in the test. Ceramographic observations showed no palladium attack and thermal degradation of ZrC. Fission products of 137Cs, 134Cs, 106Ru, 144Ce, 154Eu and 155Eu were released from the coated particles through the coating layers during the postirradiation heating. Diffusion coefficients of 137Cs and 106Ru in the ZrC coating layer were evaluated from the release curves based on a diffusion model. 137Cs retentiveness of the ZrC coating layer was much better than that of the SiC coating layer. ((orig.))

  8. Measurement of leaching from simulated nuclear-waste glass using radiotracers

    International Nuclear Information System (INIS)

    The use of radiotracer spiking as a method of measuring the leaching from simulated nuclear-waste glass is shown to give results comparable with other analytical detection methods. The leaching behavior of 85Sr, 106Ru, 133Ba, 137Cs, 141Ce, 152Eu, and other isotopes is measured for several defense waste glasses. These tests show that radiotracer spiking is a sensitive, multielement technique that can provide leaching data, for actual waste elements, that are difficult to obtain by other methods. Additionally, a detailed procedure is described that allows spiked glass to be prepared with a suitable distribution of radionuclides

  9. Three-dimensional plume dynamics in the vadose zone: PORFLO-3 modeling of a defense waste leak at Hanford

    International Nuclear Information System (INIS)

    In 1973, approximately 450 m3 of liquid containing radioactive and chemical wastes leaked from the 241-T-106 single-shell tank into the vadose zone at the US Department of Energy's Hanford Site in south-central Washington State. The extent of the 137Cs, 144Ce, and 106Ru contaminant plumes in the vadose zone was estimated in 1973 and 1978 by gamma spectrometry in monitoring wells. Using site data and the PORFLO-3 computer model, a three-dimensional, transient plume migration model was developed for 106Ru and 137Cs. The model was calibrated to the 1973 measured plumes of 106Ru and 137Cs. The calibrated model was then used to study plume migration up to 1990. The simulated 106Ru distribution for 1978 extended deeper than reported values. The simulated distribution of 137Cs for 1978 approximated the measured distribution; the 1973 and 1978 137Cs distributions are similar because of the long half-life and high sorption coefficient of 137Cs. 8 figs., 15 refs

  10. Gamma emitting fission products in surface sediments of the Ravenglass estuary

    Energy Technology Data Exchange (ETDEWEB)

    Aston, S.R.; Stanners, D.A. (Lancaster Univ. (UK))

    1982-04-01

    The occurrence of some fission products from the Sellafield (formerly Windscale) nuclear fuel reprocessing facility has been determined for surface sediments from forty locations in the Ravenglass estuary, North-West England. The influence of the silt-sized fraction in the sediments on the geographic distribution of /sup 137/Cs is clearly important, and to a lesser extent also influences the distributions of /sup 106/Ru, /sup 134/Cs + /sup 95/Zr/Nb and /sup 144/Ce. The data are compared with recently published results reported by the Ministry of Agriculture, Fisheries and Food for a monitoring site in this estuary.

  11. Dynamics of contents and organic forms of radionuclide compounds in the liquid phase of forest soils in the zone of contamination from the Chernobyl Nuclear Power Plant

    International Nuclear Information System (INIS)

    In the profile of forest soils in a 30-km zone around the Chernobyl nuclear power plant (NPP), in areas characterized by different positions in relation to the source of emission, the authors determined the relative contents of long-lived radionuclides 106Ru, 134,137Cs, and 144Ce in soil solutions (as of 1987). On the example of 137Cs, they consider the dynamics (1987-1990) of relative contents and forms in which the radionuclide is found in the liquid phase of soils in the zone of radioactive contamination from the Chernobyl NPP

  12. Silviculture-ecological consequences of forest pollution due to radioactive effluents

    International Nuclear Information System (INIS)

    Radioactive contamination effect on the forest areas of Pripyat' Polessie is considered. Radiation processes in damaged pinetree plantations are characterized. Radionuclide migration dependent on soil types and tree stocks is analyzed. The data analysis has shown the evidence of 144Ce, 1'37Cs, 134Cs, 106Ru in 3 years after radioactive contamination in the controlled area. By the end of the third year a significant radionuclide migration had occurred between the forest floor and lower aquifers. refs. 2; figs. 2; tabs. 8

  13. Behaviour of solid fission products in the HTGR coated fuel particles

    International Nuclear Information System (INIS)

    Results of profile measurements for volume concentrations of 134,137Cs, 144Ce, 155Eu, 106Ru and fissionable material in the HTGR coated fuel particles which have been subjected to standard tests in the temperature range of 1273-2133 K and at burnup up to 17% fima are presented. Values of the effective coefficients of cesium diffusion in kern and protective coating of fuel particles which were subjected to standard in-pile tests in spherical fuel elements at the temperature of 1273 K and the burnup up to 15% fima as well as the value of relative release of solid fission products from the samples studied are given

  14. 1. Quarterly progress report 1984

    International Nuclear Information System (INIS)

    This report of the SCPRI exposes an interpretation of the principal results concerning the surveillance of radioactivity in the environment: atmospheric dusts, rainwater, surface water, underground water, sewage water, drinking water, food chain, sea water around nuclear plant sites and other sites. The activities of various radioisotopes are presented in tables (7Be, 54Mn, 58Co, 60Co, 90Sr, 95Nb, 106Ru, 110Ag, 125Sb, 131I, 134Cs, 137Cs, 144Ce, 226Ra, U, K, T and Rn). This report exposes also the state of surveillance and assistance operations on work sites and, the state of incidents along the three months; a bibliographic selection is also presented

  15. Characterization of Inner Tracker silicon prototype sensors using a 106 Ru-source and a 1083 nm laser system

    CERN Document Server

    Bauer, C; Pugatch, V; Schmelling, M; Schwingenheuer, B; Sievers, P

    2001-01-01

    Silicon strip sensors will be used as technology for the LHCb Inner Tracker. The signal-to-noise ratio (S/N) and the charge division among two neighbouring strips are important sensor parameters. In order to investigate the charge sharing between two adjacent strips, measurements with a 1083 nm laser were performed. Minimum ionizing electrons from a ruthenium-source were used to study the S/N-performance of the silicon sensors. The S/N-measurements were also performed with sensors after irradiation with 24 GeV protons up to a fluence of 1.7*10^14 cm^-2, corresponding to more than 10 years of LHCb Inner Tracker operation in the most irradiated zones.

  16. A Dosimetry of 106-Ru - 106- Rh Electron-Photon Field with LiF TLD-100 'Microcubes'

    International Nuclear Information System (INIS)

    Background and purpose: Ru-Rh eye applicators are used for the radiotherapy of eye malignancies such as melanomas. The producer (BEBIG GmbH) declares ±30% dose uncertainty in the applicator certificate. There is an obvious need to overcome this large imprecision. Our goal is to establish a method that is fast and reliable and which reduces dose uncertainty to below ±10%. Materials and methods: A pleksiglas phantom containing spherical calottes was constructed for this purpose. It allows measurements of surface homogeneity, absolute surface dose rates and depth doses in 2 mm steps, on and off the symmetry axis. Very small, 1x1x1 mm3 thermoluminescent dosimeters (TLD) were chosen as dosimeters. They have to be calibrated adequately for Ru-Rh dosimetry. To do that, 60Co/electron field response ratio of TLDs was investigated and correction factors were established. Doses to the base of optic nerve were considered. Results: The 60Co/electron beam response ratio of TLDs is in agreement with measured and calculated results reported by other authors (for LiF TLD-100 of different dimensions). The measurements of surface dose rate homogeneity show deviations of up to 15% of the mean surface dose rate. However, surface inhomogeneities average out deeper in the phantom. Absolute surface dose rates were found lower than those declared by the producer by 6.2%, averaged over 8 applicators investigated. On and off axis depth doses are highly uniform over angle θ=40 degrees from symmetry axis, up to 6 mm in depth. Therefore, depth doses form spherical isodose surfaces within stated angle, spanning at least 1.47 steradians. Depth dose functions were interpolated to the measured data for practical routine use. Conclusions: The method developed here has overall combined uncertainty <±6%, and therefore reduces significantly uncertainty declared by the producer. Also, it proved to be stable on repeated measurements. (author)

  17. Measurement of dose rate from 106Ru/106Rh ophthalmic applicators by means of alanine-polymer foils

    International Nuclear Information System (INIS)

    Ophthalmic applicators are used in radiotherapy for the treatment of malignant choroidal melanomas. The applicators are positioned on the eye at the base of the tumor for a period of a few days up to 2 weeks. They are commercially available in the form of caps of a spherical radius of 12 or 13 mm. Two or three fixing lugs are used for suturing the applicator to the eye. The applicators are made of silver. The active layer is covered with 0.1 mm silver in the concave direction, and 0.9 mm silver in the convex direction. The β-radiation emitted from the concave side may be used for treatment, to a depth up to 5 mm. Measurements of dose rate by means of ESR/alanine dosimetry and TLD are described. It is concluded that ESR/dosimetry and TLD are well suited for this application. (author)

  18. Concentration and depuration of some radionuclides present in a chronically exposed population of mussels (Mytilus edulis)

    Energy Technology Data Exchange (ETDEWEB)

    Clifton, R.J.; Stevens, H.E.; Hamilton, E.I.

    1983-03-01

    Factors are described which affect the concentration (p Ci g/sup -1/ dry wt) and loss of /sup 241/ Am, /sup 239 +240/Pu, /sup 238/Pu, /sup 144/Ce, /sup 137/Cs, /sup 134/Cs, /sup 106/Ru, /sup 95/Zr and /sup 95/Nb in an exposed population of mussels Mytilus edulis L. from Ravenglass on the Esk estuary, Cumbria, UK which receives radioeffluents from the British Nuclear Fuels Ltd. (BNFL) plant at Sellafield, some 10 km to the north. Tidal position and mussel body size have a negligible influence on the concentration of /sup 241/Am, /sup 137/Cs and /sup 106/Ru in the total soft tissue, but variation in soft tissue weight throughout the year has a considerable influence on the apparent concentration and depuration times of these radionuclides. Apart from the clearance (tsub(1/2) biol, 1 to 3 h) of sediment-associated activity from the digestive tract, the depuration rate profiles follow a single component clearance curve with a biological half-life in excess of 200 d for /sup 241/ Am, /sup 239 +240/Pu, /sup 238/Pu and /sup 144/Ce, and of 40 d for /sup 137/Cs. The clearance of /sup 106/Ru is more complex and consists of a 3 component depuration profile with biological half-lives of 6 h, 12 d and 260 d. The depuration profiles presented in this work are for chronically ingested isotopes under natural conditions; acute exposure will most likely result in different profiles, especially those derived from laboratory spiking experiments. Isotope ratio data support the hypothesis that the main route of entry into the mussel for the majority of the radionuclides studied is from the water.

  19. Calculated activities of some isotopes in the RA reactor highly enriched fuel significant for possible environmental contamination - Operational report

    International Nuclear Information System (INIS)

    This report contains calculation basis and obtained results of activities for three groups of isotopes in the RA reactor 80% enriched fuel element. The following isotopes are included: 1) 85mKr, 87Kr, 88Kr, 131J, 132J, 133J, 134J, 135J, 133Xe, 138Xe i 138Cs, 2) 89Sr, 90Sr, 91Sr, 92Sr, 95Zr, 97Zr, 103Ru, 105Ru, 106Ru, 129mTe, 134Cs, 137Cs, 140Ba, 144Ce, kao i 3) 238Pu, 239Pu i 240Pu. It was estimated that the fuel is exposed to mean neutron flux. The periodicity of reactor operation is taken into account. Calculation results are given dependent on the time of exposure. These results are to be used as source data for Ra reactor safety analyses

  20. The Chernobyl fallout in Greece and its effects on the dating of archaeological materials

    International Nuclear Information System (INIS)

    The effects of the fallout from the nuclear reactor accident at Chernobyl have been monitored at various sites in Greece. Here we present the first estimates of gamma dose rates, an essential parameter in the dating of archaeological materials by thermoluminescence (TL) and ESR methods. The dose rates are derived from the long-lived radionuclides of 137Cs, 134Cs, 106Ru and 144Ce (with t1/2 ≥ 1 yr). The present dose rates vary between 30 and 60 mrad/yr, but maximum values of around 811 mrad/yr have also been recorded, for ground-surface exposures. These dose rate values must be regarded as very significant to TL and ESR dating of samples from now on and a correction factor should be applied. (orig.)

  1. Critical pathway studies for selected radionuclides. Part of a coordinated programme on environmental monitoring for radiological protection in Asia and the Far East

    International Nuclear Information System (INIS)

    The programme carried out critical pathway studies for selected radionuclides (60Co, 63Ni, 59Fe, 54Mn, sup(110m)Ag, 106Ru and 144Ce) and assessed population exposure in the vicinity of Tarapur Atomic Power Station. The following topics are covered under the programme. (i) Demographic study of dietary habits and consumption data for Tarapur population. (ii) Concentration and accumulation of radionuclides in food products. (iii) Determination of radionuclides in sea water, silt, marine algae and marine organisms at Tarapur Atomic Power Station (TAPS) Site. (iv) Behaviour of radionuclides released to marine environment. (v) Evaluation of critical exposure pathway. (vi) Population exposure in the vicinity of Tarapur Atomic Power Station

  2. Specific processes in solvent extractiotn of radionuclide complexes

    International Nuclear Information System (INIS)

    The doctoral thesis discusses the consequences of the radioactive beta transformation in systems liquid-liquid and liquid-ion exchanger, and the effect of the chemical composition of liquid-liquid systems on the distribution of radionuclide traces. A model is derived of radiolysis in two-phase liquid-liquid systems used in nuclear chemical technology. The obtained results are used to suggest the processing of radioactive wastes using the Purex process. For solvent extraction the following radionuclides were used: 59Fe, 95Zr-95Nb, 99Mo, sup(99m)Tc, 99Tc, 103Pd, 137Cs, 141Ce, 144Ce-144Pr, 234Th, and 233Pa. Extraction was carried out at laboratory temperature. 60Co was used as the radiation source. Mainly scintillation spectrometry equipment was used for radiometric analysis. (E.S.)

  3. The accumulation of radionuclides by Dreissena polymorpha molluscs - The Accumulation of Radionuclides from Water and Food in the Dreissena polymorpha Mollusks

    Energy Technology Data Exchange (ETDEWEB)

    Jefanova, O.; Marciulioniene, D. [Nature Research Centre, Akademijos str. 2, LT-08412 Vilnius, Lietuva (Lithuania)

    2014-07-01

    The specific activity of {sup 137}Cs, {sup 60}Co, {sup 54}Mn, {sup 90}Sr was measured in mollusks Dreissena polymorpha samples from lake Drukshiai that is the cooling pond of the Ignalina NPP. Item the accumulation of {sup 137}Cs, {sup 90}Sr, {sup 144}Ce, {sup 106}Ru in the mollusks from water and from phytoplankton which is a part of their diet was evaluated under laboratory conditions. The data of long-term (1991-2009) studies conducted at six monitoring stations of lake Drukshiai show that in 1991 {sup 137}Cs in mollusks Dreissena polymorpha was found only in that lake's area which was influenced by the effluent that got into lake from the industrial drainage channel of Ignalina NPP. In later periods of the investigation the {sup 137}Cs specific activity was detected in mollusks samples which had been collected at other monitoring stations (the aquatory of lake Drukshiai). Meanwhile {sup 60}Co and {sup 54}Mn in Dreissena polymorpha were detected only in that lake's area which was impacted by the industrial drainage channel. The data of long-term investigation show that the major amount of radionuclides has come into lake Drukshiai through the industrial drainage system of Ignalina NPP. Albeit {sup 137}Cs, {sup 90}Sr, {sup 144}Ce, {sup 106}Ru get into the mollusks through a large amount of the water rather than from the food (phytoplankton), therefore the food can also be the main source of radionuclides in the organism of these mollusks in aquatic environment when there are low levels of specific activities of these radionuclides. (authors)

  4. Studies of environmental radioactivity in Cumbria

    International Nuclear Information System (INIS)

    Five stations collecting samples of atmospheric deposition were set up in north Cumbria along a line running inland from the coast for about 17 km. Sampling was continuous from September 1980 to September 1981. Monthly samples were analysed for 106Ru, 137Cs, 144Ce, 238Pu, sup(239,240)Pu, 241Am, 7Be and stable Na, Cl and Al. The objective of the work was to measure the deposition of radionuclides as a function of distance from the sea. By estimating the contributions to the deposition of nuclear weapon test material and of the atmospheric discharges from the British Nuclear Fuels plc works at Sellafield, the effects of the transfer to air and land of radionuclides in the sea could be established. The marine radionuclides were due to the discharges to sea from the Sellafield works. The measurements showed that the deposition was largely due to the sea-to-land transfer process. The highest depositions observed were at 20 m from high water mark, the annual values (rounded, in Bq m-2) being 106Ru, 500; 137Cs, 650; plutonium, 70; 241Am, 30. The highest concentrations in rainwater for the radionuclides studied were less than 3 per cent of the fresh water limits (drinking only) GDL values. The highest estimated accumulations in soil due to atmospheric deposition were less than 1 per cent of the limits. (author)

  5. Release behavior of metallic fission products from pyrocarbon-coated uranium-dioxide particles at extremely high temperatures

    Energy Technology Data Exchange (ETDEWEB)

    Hayashi, Kimio; Fukuda, Kousaku (Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment)

    1990-04-01

    Uranium-dioxide particles coated by pyrocarbon (BISO), which were irradiated at 1,300 {approx} 1,400degC to burnups of ca. 1% FIMA, were heated isochronally and isothermally at temperatures between 1,600 and 2,300degC. Release fractions of {sup 137}Cs, {sup 155}Eu and {sup 106}Ru were larger than 10{sup -2} after heating at 2,000degC for 2 h; the results were in contrast to much smaller release fractions from TRISO particles with intact silicon-carbide (SiC) coating. The release of {sup 137}Cs and {sup 144}Ce from the BISO particle was controlled by diffusion in the dense pyrocarbon layer at temperatures between 1,600 and 2,300degC, while that of {sup 155}Eu and {sup 106}Ru was controlled by diffusion in the fuel kernel above 1,800degC. These results can be used as reference data on release behavior of the fission products from TRISO particles with defective SiC layers. (author).

  6. Release behavior of metallic fission products from pyrocarbon-coated uranium-dioxide particles at extremely high temperatures

    International Nuclear Information System (INIS)

    Uranium-dioxide particles coated by pyrocarbon (BISO), which were irradiated at 1,300 ∼ 1,400degC to burnups of ca. 1% FIMA, were heated isochronally and isothermally at temperatures between 1,600 and 2,300degC. Release fractions of 137Cs, 155Eu and 106Ru were larger than 10-2 after heating at 2,000degC for 2 h; the results were in contrast to much smaller release fractions from TRISO particles with intact silicon-carbide (SiC) coating. The release of 137Cs and 144Ce from the BISO particle was controlled by diffusion in the dense pyrocarbon layer at temperatures between 1,600 and 2,300degC, while that of 155Eu and 106Ru was controlled by diffusion in the fuel kernel above 1,800degC. These results can be used as reference data on release behavior of the fission products from TRISO particles with defective SiC layers. (author)

  7. Transfer of radionuclides to man from greylag geese Anser anser and wigeon Anas penelope grazing the saltmarshes at Ravenglass

    Energy Technology Data Exchange (ETDEWEB)

    Lowe, V.P.W.; Horrill, A.D.

    1986-01-01

    The greylag goose and wigeon are both traditional quarry of wildfowlers. Populations of these birds in the Ravenglass estuary feed and roost on saltmarshes containing radioactivity originating from the Sellafield reprocessing plant. There is therefore, via the meat, a potential pathway for the transfer of radionuclides to man. The birds' intake of gamma-emitting fission and activation products, including /sup 60/Co, /sup 95/Nb, /sup 95/Zr, /sup 106/Ru, /sup 144/Ce, /sup 134/Cs, /sup 137/Cs, /sup 154/Eu, /sup 155/Eu and /sup 241/Am, was investigated by examining their concentrations in vegetation from the feeding areas and in their faeces. Muscle and liver tissues were also analysed. Only /sup 134/Cs and /sup 137/Cs were detected and quantified in breast muscle. Estimated transfer coefficients for /sup 137/Cs were very similar for both species. A single person would have had to consume in excess of the total number of wigeon shot or the total population of geese to obtain even 1% of his or her Annual Limit on Intake.

  8. Chernobyl radionuclides in a Black Sea sediment trap.

    Science.gov (United States)

    Buesseler, K O; Livingston, H D; Honjo, S; Hay, B J; Manganini, S J; Degens, E; Ittekkot, V; Izdar, E; Konuk, T

    The Chernobyl nuclear power station accident released large quantities of vaporized radionuclides, and, to a lesser extent, mechanically released small (less than 1-10 micron) aerosol particles. The total release of radioactivity is estimated to be out of the order of 1-2 x 10(18) Bq (3-5 x 10(7) Ci) not allowing for releases of the xenon and krypton gases. The 137Cs releases of 3.8 x 10(16) Bq from Chernobyl can be compared to 1.3 x 10(18) Bq 137Cs released due to atmospheric nuclear weapons testing. Chernobyl-derived radionuclides can be used as transient tracers to study physical and biogeochemical processes. Initial measurements of fallout Chernobyl radionuclides from a time-series sediment trap at 1,071 m during June-September 1986 in the southern Black Sea are presented. The specific activities of 137Cs, 144Ce and 106Ru in the trap samples (0.5-2, 4-12 and 6-13 Bq g-1) are independent of the particle flux while their relative activities reflect their rates of scavenging in the order Ce greater than Ru greater than Cs. PMID:3670387

  9. Extrapolation of experimental data on late effects of low-dose radionuclides in man

    International Nuclear Information System (INIS)

    The situation of living of population on radionuclide contamination areas was simulated in the experimental study using white strainless rats of different ages. The significance of age for late stochastic effects of internal radionuclide contamination with low doses of 131I, 137Cs, 144Ce and 106Ru was studied. Some common regularities and differences in late effects formation depending on age were found. Results of the study showed that the number of tumors developed increased in groups of animals exposed at the youngest age. The younger animal at the moment of internal radionuclide contamination, the higher percentage of malignant tumors appeared. It was especially so for tumors of endocrine glands (pituitary, suprarenal,- and thyroid). Differences in late effects formation related to different type of radionuclide distribution within the body were estimated. On the base of extrapolation the conclusion was made that human organism being exposed at early postnatal or pubertal period could be the most radiosensitive (1.5-2.0 or sometimes even 3-5 times higher than adults). Data confirmed the opinion that children are the most critical part of population even in case of low dose radiation exposure. (author)

  10. Determination of gamma-emitting radionuclides in the inter-tidal sediments off Balochistan (Pakistan) Coast, Arabian Sea.

    Science.gov (United States)

    Akram, M; Qureshi, Riffat M; Ahmad, Nasir; Solaija, Tariq Jamal

    2007-01-01

    Natural radionuclide contents of 226Ra, 228Ra and (40)K were studied for inter-tidal sediments collected from selected locations off the745 km long Balochistan Coast using HPGe detector based gamma-spectrometry system. The sampling zone extends from the beaches of Sonmiani (near Karachi metropolis) through Jiwani (close to the border of Iran). The natural radioactivity levels detected in various sediment samples range from 14.4 +/- 2.5 to 36.6 +/- 3.8 Bq kg(-1) for 226Ra, 9.8 +/- 1.2 to 35.2 +/- 2.0 Bq kg(-1) for (228)Ra and 144.6 +/- 9.4 to 610.5 +/- 23.9 Bq kg(-1) for (40)K. No artificial radionuclide was detected in any of the marine coastal sediment samples. 137Cs, (60)Co, 106Ru and 144Ce contents in sediment samples were below the limit of detection. The measured radioactivity levels are compared with those reported in the literature for coastal sediments in other parts of the world. The information presented in this paper will serve as the first ever local radioactivity database for the Balochistan/Makran Coastal belt of Pakistan. The presented data will also contribute to the IAEA's, Asia-Pacific Marine Radioactivity Database (ASPAMARD) and the Global Marine Radioactivity Database (GLOMARD).

  11. Burn-up determination of irradiated uranium oxide by means of direct gama spectrometry and by radiochemical method

    International Nuclear Information System (INIS)

    The burn-up of thermal neutrons irradiated U3O8 (natural uranium) samples has been determined by using both direct gamma spectrometry and radiochemical methods and the results obtained were compared. The fission products 144Ce, 103Ru, 106Ru, 137Cs and 95Zr were chosen as burn-up monitors. In order to isolate the radioisotopes chosen as monitors, a radiochemical separation procedure has been established, in which the solvent extraction technique was used to separate cerium, cesium and ruthenium one from the other and all of them from uranium. The separation between zirconium and niobium and of both elements from the other radioisotopes and uranium was accomplished by means of adsorption on a silica-gel column, followed by selective elution of zirconium and of niobium. When use was made of the direct gamma-ray spectrometry method, the radioactivity of each nuclide of interest was measured in presence of all others. For this purpose use was made of gamma-ray spectrometry and of a Ge-Li detector. Comparison of burn-up values obtained by both methods was made by means of Student's 't' test, and this showed that results obtained in each case are statistically equal. (Author)

  12. Interaction of radionuclides with geomedia associated with the Waste Isolation Pilot Plant (WIPP) site in New Mexico

    International Nuclear Information System (INIS)

    A survey of the potential of geological media from the vicinity of the Waste Isolation Pilot Plant site in Southeastern New Mexico for retardation of radionuclide migration in an aqueous carrier was conducted. The survey included the measurement of sorption coefficients (Kd) for twelve radionuclides between three natural water simulants and ten samples from various geological strata. The nuclides included 137Cs, 85Sr, 131I, 99Tc, 125Sb, 144Ce, 152Eu, 153Gd, 106Ru, 243Am, 244Cm, and 238Pu. The compositions of the simulant solutions were those expected of water in contact with potash minerals or halite deposits in the area and in a typical groundwater found in the Delaware Basin. The geological samples were obtained from potential aquifers above and below the proposed repository horizons and from bedded salt deposits in the repository horizons. In brine solutions, Tc and I were not significantly adsorbed by any of the minerals and Cs and Sr showed minimal adsorption (Kd's 103 and Ru and Sb Kd's varied in the range of 25 to > 103. In the groundwater simulant, Tc and I showed the same behavior, but the Kd's of the other nuclides were generally higher. Some initial parametric studies involving pH, trace organic constituents in the simulant solutions, and radionuclide concentrations were carried out. Significant differences in the observed Kd's can result from varying one or more of these solution parameters

  13. Neutron cross sections of 28 fission product nuclides adopted in JENDL-1

    International Nuclear Information System (INIS)

    This is the final report concerning the evaluated neutron cross sections of 28 fission product nuclides adopted in the first version of Japanese Evaluated Nuclear Data Library (JENDL-1). These 28 nuclides were selected as being most important for fast reactor calculations, and are 90Sr, 93Zr, 95Mo, 97Mo, 99Tc, 101Ru, 102Ru, 103Rh, 104Ru, 105Pd, 106Ru, 107Pd, 109Ag, 129I, 131Xe, 133Cs, 135Cs, 137Cs, 143Nd, 144Ce, 144Nd, 145Nd, 147Pm, 147Sm, 149Sm, 151Sm, 153Eu and 155Eu. The status of the experimental data was reviewed over the whole energy range. The present evaluation was performed on the basis of the measured data with the aid of theoretical calculations. The optical and statical models were used for evaluation of the smooth cross sections. An improved method was developed in treating the multilevel Breit-Wigner formula for the resonance region. Various physical parameters and the level schemes, adopted in the present work are discussed by comparing with those used in the other evaluations such as ENDF/B-IV, CEA, CNEN-2 and RCN-2. Furthermore, the evaluation method and results are described in detail for each nuclide. The evaluated total, capture and inelastic scattering cross sections are compared with the other evaluated data and some recent measured data. Some problems of the present work are pointed out and ways of their improvement are suggested. (author)

  14. Biokinetics and dose assessment of radionuclides in juveniles

    International Nuclear Information System (INIS)

    In the aftermath of the Chernobyl accident, it becomes evident that dose coefficients for members of the public are necessary. International Commission on Radiological Protection (ICRP) established a task group of Committee 2 charged with the assessment of dose coefficients as a function of an individual's age. However, little data is available on the biokinetics of radionuclides in juvenile and there is a need to develop age-dependent biokinetic models, such as for the gastrointestinal tract. The present paper reviewed an outline on characteristics of biokinetics of radionuclides in juvenile animals focusing on the previous experimental data. The following radionuclides are discussed: 54Mn, 60Co, 65Zn, 75Se, 106Ru, 110mAg, 115mCd, 125Sb, 137Cs, 141Ce, 203Hg and 3H. Generally, intestinal absorption and whole-body retention of radionuclides in juveniles were higher than that of adult. In the case of sucklings, it is very important to study how radionuclides are transferred through the placenta and milk. The transfer rate of radionuclides through the placenta and milk is dependent on the period of gestation at the time of dosing. The IDES(Internal Dose Estimation System) which is based on the ICRP model was used for dose calculation. We modified the IDES using the biokinetic data which was gained animal experiment. The IDES is flexible because the absorbed dose can be calculated by substituting arbitrary physical and physiological parameters and also substituting ingested dose coefficients not only for the ICRP Reference Man, but also for Japanese of 1 year old, 5 years old, 10 years old, 15 years old and the adult, respectively. (author)

  15. Passive gamma analysis of the boiling-water-reactor assemblies

    Science.gov (United States)

    Vo, D.; Favalli, A.; Grogan, B.; Jansson, P.; Liljenfeldt, H.; Mozin, V.; Schwalbach, P.; Sjöland, A.; Tobin, S.; Trellue, H.; Vaccaro, S.

    2016-09-01

    This research focused on the analysis of a set of stationary passive gamma measurements taken on the spent nuclear fuel assemblies from a boiling water reactor (BWR) using pulse height analysis data acquisition. The measurements were performed on 25 different BWR assemblies in 2014 at Sweden's Central Interim Storage Facility for Spent Nuclear Fuel (Clab). This study was performed as part of the Next Generation of Safeguards Initiative-Spent Fuel project to research the application of nondestructive assay (NDA) to spent fuel assemblies. The NGSI-SF team is working to achieve the following technical goals more easily and efficiently than in the past using nondestructive assay (NDA) measurements of spent fuel assemblies: (1) verify the initial enrichment, burnup, and cooling time of facility declaration; (2) detect the diversion or replacement of pins, (3) estimate the plutonium mass, (4) estimate the decay heat, and (5) determine the reactivity of spent fuel assemblies. The final objective of this project is to quantify the capability of several integrated NDA instruments to meet the aforementioned goals using the combined signatures of neutrons, gamma rays, and heat. This report presents a selection of the measured data and summarizes an analysis of the results. Specifically, trends in the count rates measured for spectral lines from the following isotopes were analyzed as a function of the declared burnup and cooling time: 137Cs, 154Eu, 134Cs, and to a lesser extent, 106Ru and 144Ce. From these measured count rates, predictive algorithms were developed to enable the estimation of the burnup and cooling time. Furthermore, these algorithms were benchmarked on a set of assemblies not included in the standard assemblies set used by this research team.

  16. Transfer of nuclides from the water phase to the sediments during normal and extraordinary hydrological cycles

    International Nuclear Information System (INIS)

    Atucha I and Atucha II nuclear power plants are located on the right margin of the Parana de las Palmas river. This river belongs to the Cuenca del Plata, whose 1982-1983 hydrologic cycle registered the greatest freshets of the century. Works and studies previously fixed had to be altered and investigations were adapted to the possibilities and the particular hydric conditions verified. Considerations on the transfer of nuclides between water and sediments are presented. The floods reduce the water-sediments contact time on the bed of the river. In outer areas, the waters labelled by the nuclear power plant effluent discharge favor the infiltration in alluvial soils, as well as the exchange with the sediments. The investigations carried out for the phase near to the discharge of liquid effluents (related to the critical group) made possible to prove the characteristics of the path of the liquid wastes released, the distribution coefficient and the fixation or penetrability of some nuclides in soils of the floody valley. In this manner, a balance of radioactive nuclides incorporated to soils and sediments from the neighbourhood of Atucha and the water-course of Parana de las Palmas river is obtained. The presence of 60Co and 137Cs in the floody soils on the right margin of this river was detected and measured during the greatest flood of the century. On the other hand, 144Ce, 51Cr, 106Ru and 90Sr have not been detected. The detection of artificial radioisotopes turns out to be impossible in normal hydrological years, even in the sorroundings of the nuclear power plant or the critical group (from the point of view of the surface waters, The Fishing Club, 3 km down stream). (M.E.L.)

  17. Radioactive contamination of bottom sediments in the upper reaches of the Techa river: analysis of the data obtained in 1950 and 1951.

    Science.gov (United States)

    Mokrov, Yury G

    2003-10-01

    A stationary sorption model has been developed for re-evaluating and analysing archive data from 1950-1951 on the radioactive contamination of Techa river bottom sediments close to the site of liquid radioactive waste discharge. In general, good agreement was obtained between calculations and measurements, which substantiates further the assumptions and conclusions in two preceding articles, on the radionuclide composition of discharged liquid radioactive waste. Estimates on the effective liquid radioactive waste discharges given here are significantly different from those deduced in the 1950s, i.e. in summer 1950 and October 1951. The results are discussed in relation to the Techa River Dosimetry System 2000 (TRDS-2000) that has recently been presented to serve as a means for estimating doses to the Techa river residents. Parameter values describing the exponential decrease of bottom sediment contamination along the river due to short-lived radionuclides, such as (106)Ru, and (144)Ce, agree reasonably with those used in TRDS-2000. However, for other radionuclides, such as (95)Zr, (95)Nb, (91)Y, (90)Sr and (137)Cs, substantial differences are found. It is demonstrated that water flow rate, width of the river, and surface area of bottom sediments are important parameters which were not adequately taken into account in TRDS-2000. Also, the stirring-up of contaminated bottom sediments and their subsequent transport by the water flow are seen to be an important mechanism that governs the radionuclide transport downstream. This mechanism was not included in the TRDS-2000 model. It is concluded that the sorption model used in TRDS-2000 for the reconstruction of radioactive contamination of water and bottom sediments of the Techa river in 1949-1951, is subject to considerable errors. While the present paper is focussed on details of the dosimetric modelling, the implications for the Techa river dosimetry are major. They will be further elucidated in a forthcoming paper

  18. Determining initial enrichment, burnup, and cooling time of pressurized-water-reactor spent fuel assemblies by analyzing passive gamma spectra measured at the Clab interim-fuel storage facility in Sweden

    Science.gov (United States)

    Favalli, A.; Vo, D.; Grogan, B.; Jansson, P.; Liljenfeldt, H.; Mozin, V.; Schwalbach, P.; Sjöland, A.; Tobin, S. J.; Trellue, H.; Vaccaro, S.

    2016-06-01

    The purpose of the Next Generation Safeguards Initiative (NGSI)-Spent Fuel (SF) project is to strengthen the technical toolkit of safeguards inspectors and/or other interested parties. The NGSI-SF team is working to achieve the following technical goals more easily and efficiently than in the past using nondestructive assay measurements of spent fuel assemblies: (1) verify the initial enrichment, burnup, and cooling time of facility declaration; (2) detect the diversion or replacement of pins; (3) estimate the plutonium mass [which is also a function of the variables in (1)]; (4) estimate the decay heat; and (5) determine the reactivity of spent fuel assemblies. Since August 2013, a set of measurement campaigns has been conducted at the Central Interim Storage Facility for Spent Nuclear Fuel (Clab), in collaboration with Swedish Nuclear Fuel and Waste Management Company (SKB). One purpose of the measurement campaigns was to acquire passive gamma spectra with high-purity germanium and lanthanum bromide scintillation detectors from Pressurized Water Reactor and Boiling Water Reactor spent fuel assemblies. The absolute 137Cs count rate and the 154Eu/137Cs, 134Cs/137Cs, 106Ru/137Cs, and 144Ce/137Cs isotopic ratios were extracted; these values were used to construct corresponding model functions (which describe each measured quantity's behavior over various combinations of burnup, cooling time, and initial enrichment) and then were used to determine those same quantities in each measured spent fuel assembly. The results obtained in comparison with the operator declared values, as well as the methodology developed, are discussed in detail in the paper.

  19. Revascularization of calvarial, mandibular, tibial, and iliac bone grafts in rats

    DEFF Research Database (Denmark)

    Pinholt, E M; Solheim, E; Talsnes, O;

    1994-01-01

    area of harvest of bone graft is important regarding early revascularization, but the results do not support the theory that different embryological mode of development is the cause since mandibula (high 141Ce index) and calvaria (low 141Ce index) are of membranous origin and iliac bone (high 141Ce...... index) and tibia (low 141Ce index) are of endochondral origin. The difference in revascularization between the different grafts may be explained by differences in quantity of cancellous bone since cancellous bone is revascularized faster than cortical bone....

  20. Reconstruction of radionuclide contamination of the Techa River caused by liquid waste discharge from radiochemical production at the Mayak Production Association

    International Nuclear Information System (INIS)

    , rather than relying on a more uncertain reconstruction of quantities released at the point of discharge. Radionuclides considered include 90Sr, 106Ru, 137Cs, and 144Ce. Estimated concentrations of selected radionuclides at various times are presented

  1. Reconstruction of radionuclide contamination of the Techa River caused by liquid waste discharge from radiochemical production at the Mayak Production Association

    Energy Technology Data Exchange (ETDEWEB)

    Mokrov, Y.; Glagolenko, Y.; Napier, B.

    2000-07-01

    river, rather than relying on a more uncertain reconstruction of quantities released at the point of discharge. Radionuclides considered include {sup 90}Sr, {sup 106}Ru, {sup 137}Cs, and {sup 144}Ce. Estimated concentrations of selected radionuclides at various times are presented.

  2. Reconstruction of radionuclide contamination of the Techa River caused by liquid waste discharge from radiochemical production at the Mayak Production Association.

    Science.gov (United States)

    Mokrov, Y; Glagolenko, Y; Napier, B

    2000-07-01

    than relying on a more uncertain reconstruction of quantities released at the point of discharge. Radionuclides considered include 90Sr, 106Ru, 137Cs, and 144Ce. Estimated concentrations of selected radionuclides at various times are presented. PMID:10855774

  3. Influence of variations in dose and dose rates on biological effects of inhaled beta-emitting radionuclides

    International Nuclear Information System (INIS)

    The biological effects of inhaled β-emitting radionuclides, 90Y, 91Y, 144Ce and 90Sr, are being investigated in beagle dogs that received single acute exposures at 12 to 14 months of age. The aerosols studied have included 91YC13,144CeC13, 90SrC12, and 90Y, 91Y, 144Ce or 90Sr in aluminosilicate particles. Thus, 91YCl3, 144CeCl3 and the aluminosilicate containing radionuclide particles all resulted in significant exposures to lung; 91YC13, 144CeC13 an 90SrC12 resulted in significant exposures to bone; 91YC13 and 144 CeC13 resulted in significant exposures to liver. The higher initial doserate exposures have been more effective than low dose-rate exposures on a per-rad basis in producing early effects. To date (144CeO2, it was observed that, on a μCi initial lung burden per kilogram body weight basis, mice did not develop pulmonary tumours whereas beagle dogs did. To fid out the reason for this observation mice have been repeatedly exposed by inhalation to 144CeO2 to maintain lung burdens of 144Ce that resulted in radiation dose rates similar to that observed in beagle dogs. Several of the repeatedly exposed mice developed malignant pulmonary tumours. Thus, with similar dose rates and cumulative doses to the lung, mice and dogs responded in a similar manner to chronic β radiation

  4. Separation and recovery of ruthenium from radioactive liquid waste for specific medical applications - wealth from waste

    International Nuclear Information System (INIS)

    In recent past, 106Ru has emerged as one of the promising β- emitting radionuclide used in brachytherapy for the treatment of choroidal melanoma and retinoblastoma due to its favorable nuclear decay characteristics. A plaque with low amount of 106Ru activity of the order of 12 - 26 MBq (0.3 - 0.7 mCi ) is suitable for the above treatment and can be used for an adequate duration of 1-2 years due to suitable half-life (T1/2 = 1.02 y). In order to undertake the preparation of 106Ru plaque, an indigenous availability of this radionuclide with acceptable purity was explored from radioactive liquid waste having wide spectrum of fission products in line with wealth from waste strategy. Process methodology has been developed and standardized at Process Control Laboratory of Waste Immobilization Plant (WIP), Trombay for separation of 106Ru from radioactive liquid waste for intended medical application. (author)

  5. Patterns of Cs-137 and Sr-90 distribution in conjugated landscape systems

    Science.gov (United States)

    Korobova, E.

    2012-04-01

    The main goal of the study was to reveal spatial patterns of 137Cs and 90Sr distribution in soils and plants of conjugated landscapes and to use 137Cs as a tracer for natural migration and accumulation processes in the environment. The studies were based on presumptions that: 1) the environment consisted of interrelated bio- and geochemical fields of hierarchical structure depending on the level and age of factors responsible for spatial distribution of chemical elements; 2)distribution of technogenic radionuclides in natural landscapes depended upon the location and type of the initial source and radionuclide involvement in natural pathways controlled by the state and mobility of the typomorphic elements and water migration. Case studies were undertaken in areas subjected to contamination after the Chernobyl accident and in the estuary zones of the Yenisey and Pechora rivers. First observations in the Chernobyl remote zone in 1987-1989 demonstrated relation between the dose rate, 137Cs, 134Cs, 144Ce, 106Ru, 125Sb in soil cover and the location of the measured plot in landscape toposequence. Later study of 137Cs and 90Sr concentration and speciation confirmed different patterns of their distribution dependent upon the radioisotope, soil features and vegetation cover corresponding to the local landscape and landuse structure. Certain patterns in distribution and migration of 137Cs and 90Sr in soils and local food chain were followed in private farms situated in different landscape position [1]. Detailed study of 137Cs activity in forested site with a pronounced relief 20 and 25 years after the Chernobyl accident showed its stable polycentric structure in soils, mosses and litter which was sensitive to meso- and micro-relief features [2]. Radionuclide contamination of the lower Yenisey and Pechora studied along meridian landscape transects proved both areas be subjected to global 137Cs pollution while the Yenisey floodplain received additional regional contamination

  6. Accumulation of transuranic elements in the aquatic biota of the Belarusian sector of contaminated area near the Chernobyl nuclear power plant - Accumulation of transuranic elements in aquatic biota of Belarusian sector of contaminated area of Chernobyl nuclear power plant

    Energy Technology Data Exchange (ETDEWEB)

    Golubev, Alexander; Mironov, Vladislav [International Sakharov Environmental University. Box 220070, 23 Dolgobrodskaya Street, Minsk, 220070 (Belarus)

    2014-07-01

    The evolution of nuclear contamination of Belarus territory after Chernobyl accident includes the four stages: 1. Iodine-neptunium stage, caused mainly by short-lived radionuclides {sup 131}I, {sup 239}Np and others with a half-life period of several weeks; II. Intermediate stage, caused by radionuclides with a half-life period of a year ({sup 144}Ce, {sup 106}Ru, {sup 134}Cs, etc.); III. Strontium-cesium stage, caused by {sup 90}Sr and {sup 137}Cs with a half-life period of about 30 years; IV. Plutonium-americium, caused by long-lived α-emitting radionuclides {sup 241}Am (period of half-life of 432 years) and {sup 239+240}Pu, having high radio and chemo-toxicity. According to forecasts, activity of {sup 241}Am to 2050 year will increase by 2.5 times and it will be the most important dose-related factor for the aquatic biota within the Chernobyl accident zone. In 2002 - 2008 years we have studied the accumulation of trans-uranic elements (TUE, {sup 241}Am, {sup 239+240}Pu) in basic components of water body ecosystems within the Chernobyl zone - non-flowing Perstok Lake, weak-flowing Borschevka flooding and small Braginka River. Among investigated components are water, bottom sediments, submerged macrophytes (Ceratophyllum submersum, Hydrocharis morsus-ranae, Lemna minor, Nuphar lutea, Stratiotes aloides), emergent macrophytes (Typha spp.), shellfish and fish. In the soil cover in the vicinity of the Perstok Lake activity of {sup 241}Am at present is equivalent to 300 - 600 Bq.kg{sup -1}, that is the basic source of its income to the lake. Radionuclides mobility in the water environment is higher than in the soil, that facilitates the rapid incorporation of {sup 241}Am to the trophic nets of water bodies and its removal by near-water animals in the terrestrial biotopes, including outside Chernobyl zone. Thus, the activity of {sup 241}Am in bottom sediments in the Perstok Lake and Borschevka flooding in 2008 year reach respectively 324 and 131 Bq.kg{sup -1}, and the

  7. Langzeitergebnisse bei Aderhautmelanom nach 106Ruthenium-Brachytherapie

    OpenAIRE

    Krause, Nona

    2015-01-01

    Introduction: 106Ruthenium-brachytherapy (106Ru-brachytherapy) is an established therapy for small and medium-sized uveal melanomas. The aim of this study was to examine the long-time results in regard to recurrence rate, complication rate, ocular preservation, metastasis rate and survival with malignant uveal and ciliary body melanoma, as well as relevant prognosis factors, subsequent to 106Ru-brachytherapy. Methodology: In this retrospective study of all cases with uveal or with ciliary ...

  8. Toxicity studies of inhaled beta-emitting radionuclides: status report

    International Nuclear Information System (INIS)

    The influence of total dose and dose rate on the effects of inhaled beta-emitting radionuclides is being studied in laboratory animals. The radionuclides are inhaled either in a relatively soluble form (90SrCl2, 144CeCl3, 91YCl3 or 137CsCl) or in a relatively insoluble form in fused aluminosilicate particles. The organs affected depend on the solubility and chemical characteristics of the radio isotopes. Studies with young adult dogs are complemented with comparable studies in other species (mice, rats and Syrian hamsters), with animals of different ages and with animals repeatedly exposed to 144Ce

  9. Toxicity studies of inhaled beta-emitting radionuclides - status report

    International Nuclear Information System (INIS)

    The influence of total dose and dose rate pattern on the effects of inhaled β-emitting radionuclides is being studied in laboratory animals. The inhaled radionuclides were either in a relatively soluble form (90SrCl2, 144CeCl3, 91YCl3, or 137CsCl), or in a relatively insoluble form in fused aluminosilicate particles. The organs affected depend on the solubility and chemical characteristics of the radionuclides. Studies with young adult dogs are complemented by comparable studies in other species (mice, rats, and Syrian hamsters), with animals of different ages and animals repeatedly exposed to 144Ce. 12 references, 2 figures, 2 tables

  10. Revascularisation of fresh compared with demineralised bone grafts in rats

    DEFF Research Database (Denmark)

    Solheim, E; Pinholt, E M; Talsnes, O;

    2001-01-01

    Revascularisation of bone grafts is influenced by both the anatomical origin and the pre-implantation processing of the graft. We investigated the revascularisation by entrapment of 141Ce (cerium)-labelled microspheres in large, fresh and demineralised syngeneic grafts of predominantly cancellous...

  11. Separation of cerium from high level waste solution of Purex origin

    International Nuclear Information System (INIS)

    A simple solvent extraction procedure for the separation of 144Ce from Purex high level waste (HLW) is described. 2-ethylhexyl 2-ethylhexyl phosphonic acid (KSM-17) has been used as extractant. About 10 mCi of cerium was separated from HLW using this technique. This method is amenable for automation and scale up. (author)

  12. Radiation-induced liver lesions in beagle dogs

    International Nuclear Information System (INIS)

    The risk for liver disease from internally deposited beta-emitting radionuclides is unknown because there are no human populations exposed to hepatotropic beta-emitting radionuclides available for study. In this report, we discuss the hepatic lesion in dogs exposed to a beta-emitting radionuclide, 144CeCl3, and held for their life spans

  13. Comparison of the effects of inhaled alpha- and beta-emitting radionuclides on pulmonary function in the dog

    International Nuclear Information System (INIS)

    Alterations of pulmonary function in representative groups of dogs developing nonneoplastic lung disease, after single inhalation exposures to cerium-144 or plutonium-238 in relatively insoluble particulate forms, were compared. The inhaled particles had similar aerodynamic diameters and effective half-lives of retention in the lung. The mean initial lung burdens of the 144Ce- and 238Pu-exposed groups were 51 and 0.65 μCi/kg of body weight, respectively. Because of the respective ranges of the beta emissions from 144Ce and the alpha emissions from 238Pu, the lungs of the 144Ce-exposed dogs were relatively uniformly irradiated, whereas only approximately 6% of the lung tissue of rates to the 238Pu-exposed dogs was irradiated. The calculated average dose rates to the irradiated tissue were similar for both radionuclides. Pulmonary function was measured serially without sedation. Both groups developed progressive, restrictive lung disease, which ended in death from pulmonary failure. Dogs that inhaled 144Ce had an early reduction of CO diffusing capacity followed by a progressive mechanical and gas-exchange impairment similar to that reported for dogs and men exposed to external irradiation. Dogs that inhaled 238Pu had increased respiratory frequencies which often persisted for months before mechanical and gas-exchange abnormalities became evident

  14. Calculation of beta-ray dose distributions from ophthalmic applicators and comparison with measurements in a model eye

    International Nuclear Information System (INIS)

    Dose distributions throughout the eye, from three types of beta-ray ophthalmic applicators, were calculated using the EGS4, ACCEPT 3.0, and other Monte Carlo codes. The applicators were those for which doses were measured in a recent international intercomparison [Med. Phys. 28, 1373 (2001)], planar applicators of 106Ru-106Rh and 90Sr-90Y and a concave 106Ru-106Rh applicator. The main purpose was to compare the results of the various codes with average experimental values. For the planar applicators, calculated and measured doses on the source axis agreed within the experimental errors (106Ru-106Rh and 5 mm for 90Sr-90Y. At greater distances the measured values are larger than those calculated. For the concave 106Ru-106Rh applicator, there was poor agreement among available calculations and only those calculated by ACCEPT 3.0 agreed with measured values. In the past, attempts have been made to derive such dose distributions simply, by integrating the appropriate point-source dose function over the source. Here, we investigated the accuracy of this procedure for encapsulated sources, by comparing such results with values calculated by Monte Carlo. An attempt was made to allow for the effects of the silver source window but no corrections were made for scattering from the source backing. In these circumstances, at 6 mm depth, the difference in the results of the two calculations was 14%-18% for a planar 106Ru-106Rh applicator and up to 30% for the concave applicator. It becomes worse at greater depths. These errors are probably caused mainly by differences between the spectrum of beta particles transmitted by the silver window and those transmitted by a thickness of water having the same attenuation properties

  15. The relationship between revascularisation and osteogenesis in fresh or demineralised bone grafts

    DEFF Research Database (Denmark)

    Solheim, E; Pinholt, E M; Talsnes, O;

    2001-01-01

    .50, p = 0.001), no correlation could be demonstrated in demineralised grafts (r = 0.09, p = 0.6). The results may indicate differences in the mechanisms of vascularisation and osteogenesis in the grafts used fresh or after demineralization but are, at present, difficult to fully explain.......Bone formation generally depends on adequate blood flow. Failure of bone grafts has been attributed to delayed revascularisation of the graft. We compared the relationship between revascularisation and osteogenesis, evaluated as entrapment of (141)Ce-labelled microspheres and uptake of (85)Sr......, respectively, in fresh or demineralised syngeneic bone grafts 3 weeks after heterotopic implantation in rats. Whereas a moderately high linear correlation between (85)Sr and (141)Ce radioactivity was found both in the (intact) host iliac bone (r = 0.75, p = 0.0001) and implanted fresh syngeneic grafts (r = 0...

  16. 2. Quarterly progress report, 1983

    International Nuclear Information System (INIS)

    This quarterly report of the SCPRI exposes an interpretation of the principal results concerning the surveillance of radioactivity in the environment: atmospheric dusts, rainwater, surface water, underground water, irrigation water, drinking water, food chain, sea water around nuclear plant sites and other sites. The activities of various radioisotopes are presented in tables (7Be, 58Co, 60Co, 134Cs, 137Cs, 90Sr, 106Ru, K, 54Mn, U and T). A bibliographic selection is also presented

  17. Decontamination of a radioactive process waste water by adsorbing colloid flotation

    International Nuclear Information System (INIS)

    As a part of a research programme on the treatment of a radioactive process waste water by foam separation techniques, adsorbing colloid flotation was tested to remove 144Ce, 60Co, 65Zn and 89Sr from the waste water. Potassium oleate was used as the collector, and Fe(III) hydroxide, Al(III) hydroxide or Co(II) hydroxide as the coprecipitant. Under the optimal conditions; removals exceeding 99% could be achieved for 65Zn with any of the tested coprecipitants, for 144Ce with Fe(III) and Co(II) hydroxides and for 60Co with only Co(II) hydroxide. For 89Sr removals > 90% could be achieved with only Fe(III) hydroxide. The adsorbing colloid flotation process was compared with both chemical precipitation and ion exchange, and advantages of adsorbing colloid flotation were enumerated. (author)

  18. Decontamination of radioactive process waste water by adsorbing colloid flotation

    International Nuclear Information System (INIS)

    Adsorbing colloid flotation was tested to remove 144Ce, 60Co, 65Zn, and 89Sr from radioactive process waste water. Potassium oleate was used as the collector, and Fe(III) hydroxide, Al(III) hydroxide or Co(II) hydroxide as the coprecipitant. Under optimal conditions, removals exceeding 99% could be achieved for 65Zn with any of the tested coprecipitants, for 144Ce with Fe(III) and Co(II) hydroxides and for 60Co with only Co(II) hydroxide. For 89Sr removals of 90% could be achieved only with Fe(III) hydroxide. The adsorbing colloid flotation process was compared with both chemical precipitation and ion exchange. Advantages of adsorbing colloid flotation are discussed. (author)

  19. Development of A phantom for ophthalmic beta source applicator quality control using TL dosimetry

    Science.gov (United States)

    Barbosa, N. A.; da Rosa, L. A. R.; Braz, D.

    2015-11-01

    Concave eye applicators with 90Sr/90Y and 106Ru/106Rh beta ray sources are usually used in brachytherapy for the treatment of superficial intraocular tumors as uveal melanoma with thickness up to 5 mm. The calculation of the dose delivered to the eye is carried out based on the data present in the beta source calibration certificate. Therefore, it would be interesting to have a system that could evaluate that dose. In this work, an eye phantom to be used with 106Ru/106Rh betatherapy applicators was developed in solid water. This phantom can hold nine micro-cube thermoluminescent (TL) dosimeters, TLD-100. The characteristics of the TL response of the dosimeters, namely reproducibility and individual sensitivity, were determined for a 60Co source. Using Monte Carlo code MCNPX, the dose to a water eye was determined at different depths. Exposing the eye phantom with TL dosimeters to the 106Ru/106Rh applicator, it is possible to assess calibration factors using the dose values obtained by Monte Carlo simulation to each depth. Using mean calibration factors, dose values obtained by TL dosimetry were compared to the data present in the applicators certificate. Mean differences for both applicators were lower than ±10%, maximum value 17% and minimum value 0.08%. Considering that the certificate values present an uncertainty of ±20%, the calibration procedure and the developed phantom are validated and can be applied.

  20. Electrochemical investigation of rare earth amalgams

    International Nuclear Information System (INIS)

    Using the method of filtration of heterogeneous samarium amalgams, containing radioactive isotopes sup(144)Ce and sup(152)Eu, it has been shown that cerium is inserted into the solid phase of samarium amalgam, whereas europium does not cocrystallize with samarium. The solubility of praseodymium, neodymium, and gadolinium in mercury has been determined on the basis of the curves current VS time of decomposition of heterogeneous amalgams of these metals

  1. Pulmonary carcinogenesis and chronic beta irradiation of lung

    International Nuclear Information System (INIS)

    Light water nuclear power reactor fuel cycles at various stages contain substantial quantities of β-emitting radionuclides. Thus, in the event of an accident, there is potential for inhalation exposure of man to various types and forms of β-emitting radionuclides. In order to study the biological effects of such potential exposures, a series of life span studies have been initiated in which beagle dogs have been exposed to inhalation to achieve graded lung burdens of a relatively insoluble fused clay form of β-emitting radionuclides. The specific radionuclides, 90Y, 91Y, 144Ce, or 90Sr, were selected on the basis of physical half-life to produce a variety of radiation-dose patterns to the lung. Early effects have been the development of radiation pneumonitis and progressive pulmonary fibrosis. In general, dogs which receive high- and rapidly-declining dose-rate exposure from 90Y or 91Y die earlier and at lower cumulative doses than dogs exposed to 144Ce or 90Sr. By contrast, the incidence of later-occurring malignant lung tumors and the degree of inflammatory response is greater in dogs which received protracted low dose-rate exposure associated with 144Ce and 90Sr. Of particular note is the nature of the lung tumors thus far observed

  2. Comparison of the effects of inhaled alpha- and beta-emitting radionuclides on pulmonary function of the dog

    International Nuclear Information System (INIS)

    Pulmonary function changes of representative dogs after inhalation of a relatively insoluble form of 144Ce in fused aluminosilicate particles and 238PuO2 were compared. Both radionuclide forms had approximately the same effective half-life, but the 238PuO2 irradiated 11 percent of the lung while the 144Ce irradiated 100 percent. Both groups developed restrictive lung disease progressing to pulmonary failure but the sequence of functional changes differed. The first change in dogs that inhaled 144Ce was a reduced CO diffusing capacity followed later by changes in breathing pattern, lung compliance and alveolar-capillary O2 exchange. The first change in dogs that inhaled 238PuO2 was an increase in respiratory frequency which persisted for several months before nearly simultaneous changes in diffusing capacity, compliance and gas mixing. An impairment in alveolar-capillary O2 exchange occurred later in dogs that inhaled 238PuO2. Functional alterations of both groups in pulmonary failure were similar. The differences in the pattern of functional changes were thought to be related to differences in dose pattern, but the exact relationships are unknown

  3. Hodoscope module with miniature photomultipliers

    International Nuclear Information System (INIS)

    The experimental Scintillation Magnetic Spectrometer (SMS) installation, whose main element is an extended hodoscope system, is being built for the accelerator of the High Energy Laboratory of the Joint Institute for Nuclear Research. The authors describe the scintillation hodoscope of the SMS installation and present the applicable amplitude and time characteristics of several types of miniature photomultipliers (FEU-58, FEU-60, FEU-114-1, FEU-147-1, and R-1635 (Hamamatsu, Japan)), which were obtained with a 106Ru radioactive source and standard plastic scintillators of two types, based on oxazoles in polystyrene and in polymethylmethacrylate

  4. PMT signal increase using a wavelength shifting paint

    CERN Document Server

    Allada, K; Ou, L; Schmookler, B; Shahinyan, A; Wojtsekhowski, B

    2015-01-01

    We report a 1.65 times increase of the PMT signal and a simple procedure of application of a new wavelength shifting (WLS) paint for PMTs with non-UV-transparent windows. Samples of four different WLS paints, made from hydrocarbon polymers and organic fluors, were tested on a 5-inch PMT (ET 9390KB) using Cherenkov radiation produced in fused silica disks by $^{106}$Ru electrons on a `table-top' setup. The best performing paint was employed on two different types of 5-inch PMTs (ET 9390KB and XP4572B), installed in atmospheric pressure CO$_2$ gas Cherenkov detectors, and tested using GeV electrons.

  5. Solidification and storage of Savannah River Plant radioactive waste

    International Nuclear Information System (INIS)

    A conceptual process for solidification of SRP aqueous waste into high-integrity, low-leachable forms was developed. The process separates about 99.9 percent of the biological hazard from approximately 97 percent of the waste. The major biological hazard remaining in the residual salt is 106Ru, which has a 369-day half-life. Sludge and zeolite can be solidified into concrete or glass. Cost-risk analyses are being made to determine which of these forms is preferred for SRP waste. Also, studies on other parts of the conceptual process are in progress. (auth)

  6. Monthly progress report

    International Nuclear Information System (INIS)

    This monthly report of the SCPRI exposes an interpretation of the principal results concerning the surveillance of radioactivity in the environment: atmospheric dusts(air at ground level, high altitude air), rainwater, surface water, underground water, irrigation water, drinking water, food chain (milk, plants, cattle, fish), sea water around nuclear plant sites and other sites. The activities of various radioisotopes are presented in tables (7Be, 95Zr and 95Nb, 103Ru, 131I, 137Cs, 140Ba and 140La, 90Sr, 106Ru and 106Rh, 226Ra, 54Mn, U and T). A monthly bibliographic selection is also presented

  7. Monthly progress report

    International Nuclear Information System (INIS)

    This monthly report of the SCPRI exposes an interpretation of the principal results concerning the surveillance of radioactivity in the environment: atmospheric dusts (air at ground level, high altitude air), rainwater, surface water, underground water, irrigation water, drinking water, food chain (milk, plants, cattle, fish), sea water around nuclear plant sites and other sites. The activities of various radioisotopes are presented in tables (7Be, 95Zr and 95Nb, 103Ru, 131I, 137Cs, 140Ba and 140La, 90Sr, 106Ru and 104Rh, 226Ra, 54Mn, U and T). A monthly bibliographic selection is also presented

  8. Monthly progress report

    International Nuclear Information System (INIS)

    This monthly report of the SCPRI exposes an interpretation of the principal results concerning the surveillance of radioactivity in the environment: atmospheric dusts (air at ground level, high altitude air), rainwater, surface water, underground water, irrigation water, drinking water, food chain (milk, plants, cattle, fish), sea water around nuclear plant sites and other sites. The activities of various radioisotopes are presented in tables (7Be, 95Zr and 95Nb, 103Ru, 131I, 137Cs, 140Ba and 140La, 90Sr, 106Ru and 106Rh, 226Ra, 54Mn, U and T). A monthly bibliographic selection is also presented

  9. Deposition and retention of radioactive aerosols on desert vegetation

    International Nuclear Information System (INIS)

    Deposition velocities and retention times were obtained for submicron aerosols of 134Cs and 141Ce on a shrub species (Artemisia tridentata) and a grass (Elymus elimoides) in a natural desert environment. Submicron aerosols of these two nuclides were artificially generated and released over a sagebrush community in southeast Idaho during each of three seasons: spring, summer and winter, to determine the effects of weathering and plant development on aerosol deposition and retention. Information on friction velocities, roughness lengths, and particle size was also obtained

  10. Chelating agents in pharmacology, toxicology and therapeutics

    International Nuclear Information System (INIS)

    The proceedings contain 71 abstracts of papers. Fourteen abstracts were inputted in INIS. The topics covered include: the effects of chelating agents on the retention of 63Ni, 109Cd, 203Hg, 144Ce, 95Nb and the excretion of 210Po, 63Ni, 48V, 239Pu, 241Am, 54Mn; the applications of tracer techniques for studies of the efficacy of chelation therapy in patients with heart and brain disorders; and the treatment of metal poisoning with chelating agents. (J.P.)

  11. Appendix to Health and Safety Laboratory environmental quarterly report. [Fallout radionuclides deposited and in surface air at various world sites; /sup 137/Cs and /sup 90/Sr in milk and drinking water in New York City; and stable Pb in surface air

    Energy Technology Data Exchange (ETDEWEB)

    Hardy, E.P. Jr.

    1977-07-01

    Tabulated data are presented on the deposition of fallout /sup 89/Sr and /sup 90/Sr at various world land sites through 1976; the ..gamma.. spectra and content of /sup 7/Be, /sup 95/Zr, /sup 137/Cs, /sup 144/Ce, /sup 90/Sr, /sup 210/Pb, /sup 238/Pu, /sup 239/Pu, and stable Pb in samples of surface air collected during 1966 at various world sites; and the content of fallout /sup 137/Cs and /sup 90/Sr in samples of drinking water and milk collected in New York City through 1976. (CH)

  12. Radionuclide volatilization during plasmachemical reprocessing of radioactive wastes

    International Nuclear Information System (INIS)

    Volatilization of 137Cs, 60Co, 90Sr, 144Ce and α-active radionuclides under high temperature utilization of solid and liquid low- and intermediate level radioactive wastes is studied. Low temperature plasma of arc plasmatroned was used as a heat carrier in the laboratory conditions and on experimental installation with shaft furnace and direct flow plasma-chemical reactor. The lowest radionuclides lost (1-2%) was observed from the shaft furnace due to the presence of radionuclides sorbiting layer of wastes

  13. Separation of 90Sr from PUREX HLLW using N,N,N',N'-tetra (2-ethylhexyl)diglycolamide

    International Nuclear Information System (INIS)

    This paper describes the separation of 90Sr from PUREX-HLLW employing separation techniques viz. solvent extraction and precipitation. In the first step, PUREX-HLLW was subjected to solvent extraction using TBP (30% in n-dodecane) to remove residual uranium and plutonium. In the subsequent step the raffinate was treated with N,N,N',N'-tetra (2-ethylhexyl) diglycolamide (TEHDGA, 0.20M in 30% isodecyl alcohol and n-dodecane) for the bulk separation of trivalent actinides and lanthanides. The raffinate from this step containing major activity of 90Sr and other fission products such as 137Cs and 106Ru etc. forms ideal feed for 90Sr recovery. Strontium from this non alpha bearing HLLW was extracted using 0.30M TEHDGA in 5% isodecyl alcohol and n-dodecane and stripped with 0.01M HNO3. Recovery of 90Sr was found to be quantitative which was further purified from trace impurities such as 106Ru etc. and concentrated using radiochemical precipitation technique employing Fe scavenging as hydroxide followed by carbonate precipitation after adding natural Fe and Sr as carriers

  14. Monte Carlo-based Bragg-Gray tissue-to-air mass-collision-stopping power ratios for ISO beta sources

    International Nuclear Information System (INIS)

    Quantity of interest in external beta radiation protection is the absorbed dose rate to tissue at a depth of 7 mg/cm2 Dt (7 mg/cm2) in a 4-element ICRU (International Commission for Radiation Units and Measurements) unit density tissue phantom. ISO (International Organization for Standardization) 6980-2 provides guidelines to establish this quantity for beta emitters using an extrapolation chamber as a primary standard. ISO 6980-1 proposes two series of beta reference radiation fields, namely, series 1 and series 2. Series 1 covers 90Sr/90Y, 85Kr, 204Tl and 147Pm sources used with beam flattening filter and Series 2 covers 14C and 106Ru/106Rh sources used with beam flattening filter. Dt (7 mg/cm2) is realized based on measured current and set of corrections including Bragg-Gray tissue-to-air mass-stopping power ratio, (S/ρ)t,a. ISO provides (S/ρ)t,a values which are based on approximate methods. The present study is aimed at calculating (S/ρ)t,a for 90Sr/90Y, 85Kr, 106Ru/106Rh and 147Pm sources using the Monte Carlo (MC) methods and compare the same against the ISO values. By definition, (S/ρ)t,a should be independent of cavity length of the chamber which was verified in the work

  15. Monte Carlo-based Spencer-Attix and Bragg-Gray tissue-to-air stopping power ratios for ISO beta sources

    International Nuclear Information System (INIS)

    Spencer-Attix (SA) and Bragg-Gray (BG) mass-collision-stopping-power ratios of tissue-to-air are calculated using a modified version of EGSnrc-based SPRRZnrc user-code for the International Organization for Standardization (ISO) beta sources such as 147Pm, 85Kr, 90Sr/90Y and 106Ru/106Rh. The ratios are calculated at 5 and 70 μm depths along the central axis of the unit density ICRU-4-element tissue phantom as a function of air-cavity lengths of the extrapolation chamber l = 0.025-0.25 cm. The study shows that the BG values are independent of l and agree well with the ISO-reported values for the above sources. The overall variation in the SA values is ∼0.3 % for all the investigated sources, when l is varied from 0.025 to 0.25 cm. As energy of the beta increases the SA stopping-power ratio for a given cavity length decreases. For example, SA values of 147Pm are higher by ∼2 % when compared with the corresponding values of 106Ru/106Rh source. SA stopping-power ratios are higher than the BG stopping-power ratios and the degree of variation depends on type of source and the value of l. For example, the difference is up to 0.7 % at l = 0.025 cm for the 90Sr/90Y source. (authors)

  16. Long-term variations of man-made radionuclide concentrations in a bio-indicator Mytilus galloprovincialis from the French Mediterranean coast

    Energy Technology Data Exchange (ETDEWEB)

    Charmasson, S. [Institut de Protection et de Surete Nucleaire, Departement de Protection de l' Environnement, Base IFREMER, BP 330, 83507 La Seyne/mer Cedex (France); Barker, E.; Calmet, D. [Institut de Protection et de Surete Nucleaire, Departement de Protection de l' Environnement, Bois des Rames, Bt 501, 91400 Orsay (France); Pruchon, A.S.; Thebault, H. [Institut de Protection et de Surete Nucleaire, Departement de Protection de l' Environnement, Base IFREMER, BP 330, 83507 La Seyne/mer Cedex (France)

    1999-09-30

    Results from a 14-year monitoring (1984-1997) of man-made radionuclide (137Cs and 106Ru) levels in Mytilus galloprovincialis collected monthly on the French Mediterranean coast are presented. In this area sources of man-made radionuclides are on the one hand atmospheric fallout from both the past nuclear testings and the Chernobyl accident and on the other hand discharges from nuclear installations located on the Rhone River banks, especially those from the spent nuclear fuel reprocessing plant in Marcoule. Long-term variations of radionuclide concentrations in Mytilus demonstrated seasonal variations which are linked to the reproductive cycle of these organisms as well as to variations in land-based inputs of man-made radionuclides. A comparative study of these seasonal variations has been carried out with the aid of spectral analysis. Due to differences in released activities and discharge patterns, flow rates appear to govern mainly the 137Cs variations in the Rhone waters, whereas 106Ru variations are driven by the discharges. In the area under the influence of the Rhone outflow, 137Cs variations in mussels are characterized by seasonal variations which are themselves inversely correlated with variations of 137Cs concentrations in Rhone waters. This cyclic component seems to be closely linked to the mussel reproductive cycle. The possible influence of other parameters is discussed.

  17. The design and the dosimetry of bi-nuclide radioactive ophthalmic applicators

    International Nuclear Information System (INIS)

    A novel type of applicator for the treatment of intra-ocular tumors has been developed, based on the two radionuclides 106Ru/106Rh and 125I. The dose distribution of this ophthalmic plaque combines advantageous features of both radionuclides and can be optimally adapted to a tumor thickness in the range 6.5-9 mm, a size which is beyond the dosimetric limitations of the 106Ru/106Rh plaque therapy. Compared with 125I plaques a bi-nuclide plaque allows to maintain the tumor dosage while the dose in the irradiated volume outside of the target volume is significantly reduced. Consequently, radiosensitive structures within the eye can be spared more effectively. Dedicated methods have been developed for the dosimetry of this plaque. These methods are based on our own extensive dosimetric investigations with plastic scintillators. The precondition was the availability, developed in recent years, of a more accurate determination of the absolute dose rate to water of beta- and low energy emitters

  18. Dosimetry of beta-ray ophthalmic applicators: Comparison of different measurement methods

    International Nuclear Information System (INIS)

    An international intercomparison of the dosimetry of three beta particle emitting ophthalmic applicators was performed, which involved measurements with radiochromic film, thermoluminescence dosimeters (TLDs), alanine pellets, plastic scintillators, extrapolation ionization chambers, a small fixed-volume ionization chambers, a diode detector and a diamond detector. The sources studied were planar applicators of 90Sr-90Y and 106Ru-106Rh, and a concave applicator of 106Ru-106Rh. Comparisons were made of absolute dosimetry determined at 1 mm from the source surface in water or water-equivalent plastic, and relative dosimetry along and perpendicular to the source axes. The results of the intercomparison indicate that the various methods yield consistent absolute dosimetry results at the level of 10%-14% (one standard deviation) depending on the source. For relative dosimetry along the source axis at depths of 5 mm or less, the agreement was 3%-9% (one standard deviation) depending on the source and the depth. Crucial to the proper interpretation of the measurement results is an accurate knowledge of the detector geometry, i.e., sensitive volume and amount of insensitive covering material. From the results of these measurements, functions which describe the relative dose rate along and perpendicular to the source axes are suggested

  19. Hair as an indicator of the body burden of metals in relation to age

    International Nuclear Information System (INIS)

    Many factors influencing metal deposition in hair are still unknown. Animal experiments were performed to obtain data on the mechanism of transfer of elements into hair and to estimate whether hair retention is influenced by age, sex and chelating agent treatment. Experiments were performed on albino rats (Wistar strain) of different age and sex. Whole body hair (skin included) and organ retention of various elements was determined at different periods of time after intraperitoneal administration of the radioactive isotopes 115mCd, 203Hg, 54Mn, 59Fe, 65Zn, 141Ce, 137Cs, 203Pb and 85Sr. In some experiments DTPA was used for reducing body retention of 155mCd and 141Ce and DMPS for reducing 203Hg retention. Results show that hair and organ retention of elements in rats varies with age, sex and chelation treatment and such changes are specific for each element and can not be generalized. Age as a factor influencing hair retention of metals is likely to be more important for some elements than for others. In kinetic studies we found that due to differences in element distribution and kinetics, the relationship between hair and organ retention at various time intervals varies both with age and the element concerned. Sex influences not only hair but also metal retention and distribution in other organs. (author). 4 refs

  20. Passage of chromium-mordanted and rare earth-labeled fiber: time of dosing kinetics

    International Nuclear Information System (INIS)

    Coastal bermudagrass hay was labeled with Cr by the Cr-mordant procedure and with 177Lu applied to the same fiber. Neutral detergent fiber prepared from the same Coastal bermudagrass hay was labeled with Yb, 169Yb, Tb and 160Tb by soaking overnight following by thorough washing and drying. Wood chips were similarly labeled with Sm or La, and Solka Floc was labeled with 147Nd and 141Ce. The carriers, labels and times of administration to cattle were: bermudagrass fiber with both Cr and 177Lu, bermudagrass fiber with 169Yb and Solka Floc labeled with 147Nd at 0 h; bermudagrass fiber with Yb, Solka Floc with 141Ce and wood chips with Sm at 24 h; wood chips with La at 48 h; and bermudagrass fiber labeled with 160Tb at the beginning and labeled with Tb at the end of a meal. Fecal collection followed and passage characteristics were determined with a two-compartment, age-dependent model. Markers labeling the different fiber sources had different (P less than .01) passage rates (Solka Floc greater than Coastal bermudagrass greater than wood chips), but there was no difference within fiber source for rare earth passage. There also was no difference between the passage characteristics of Cr-mordant and 177Lu. However, passage rate of particles administered at the beginning of the meal (160Tb) was 42% higher than for particles at the end of the meal (Tb)

  1. Distribution of fission products in graphite sleeves and blocks of the ninth and tenth OGL-1 fuel assemblies

    International Nuclear Information System (INIS)

    Distribution of fission products in graphite sleeves and blocks of the ninth and tenth OGL-1 fuel assemblies was measured by gamma spectrometry with lathe sectioning. The assemblies were loaded with HTGR fuel compacts, which had been produced by a scaled-up facility for the High Temperature Engineering Test Reactor (HTTR) being developed by JAERI; and they were irradiated in an in-pile gas loop, OGL-1. Fission products detected in the sleeves were 137Cs, 134Cs, 155Eu, 154Eu, 144Ce, 125Sb and 110mAg. The last nuclide, however, may have been produced by activation of a stable isotope, 109Ag, contained as impurity. Effective retention capability of the sleeve was observed for 155Eu, 154Eu, 144Ce and 125Sb; while, not for 137Cs and 134Cs. Concentration of 137Cs in the graphite blocks was markedly higher at the downstream side than at the upstream side of the coolant. This was ascribed to migration of the nuclide with the coolant flow and its subsequent sorption on the surface of the block. (author)

  2. Ruthenium-106 brachytherapy for thick uveal melanoma: reappraisal of apex and base dose radiation and dose rate

    Science.gov (United States)

    Jaberi, Ramin; Sedaghat, Ahad; Azma, Zohreh; Nojomi, Marzieh; Falavarjani, Khalil Ghasemi; Nazari, Hossein

    2016-01-01

    Purpose To evaluate the outcomes of ruthenium-106 (106Ru) brachytherapy in terms of radiation parameters in patients with thick uveal melanomas. Material and methods Medical records of 51 patients with thick (thickness ≥ 7 mm and < 11 mm) uveal melanoma treated with 106Ru brachytherapy during a ten-year period were reviewed. Radiation parameters, tumor regression, best corrected visual acuity (BCVA), and treatment-related complications were assessed. Results Fifty one eyes of 51 consecutive patients including 25 men and 26 women with a mean age of 50.5 ± 15.2 years were enrolled. Patients were followed for 36.1 ± 26.5 months (mean ± SD). Mean radiation dose to tumor apex and to sclera were 71 (± 19.2) Gy and 1269 (± 168.2) Gy. Radiation dose rates to tumor apex and to sclera were 0.37 (± 0.14) Gy/h and 6.44 (± 1.50) Gy/h. Globe preservation was achieved in 82.4%. Preoperative mean tumor thickness of 8.1 (± 0.9) mm decreased to 4.5 (± 1.6) mm, 3.4 (± 1.4) mm, and 3.0 (± 1.46) mm at 12, 24, and 48 months after brachytherapy (p = 0.03). Four eyes that did not show regression after 6 months of brachytherapy were enucleated. Secondary enucleation was performed in 5 eyes because of tumor recurrence or neovascular glaucoma. Tumor recurrence was evident in 6 (11.8%) patients. Mean Log MAR (magnification requirement) visual acuity declined from 0.75 (± 0.63) to 0.94 (± 0.5) (p = 0.04). Best corrected visual acuity of 20/200 or worse was recorded in 37% of the patients at the time of diagnosis and 61.7% of the patients at last exam (p = 0.04). Non-proliferative and proliferative radiation-induced retinopathy was observed in 20 and 7 eyes. Conclusions Thick uveal melanomas are amenable to 106Ru brachytherapy with less than recommended apex radiation dose and dose rates. PMID:26985199

  3. Determination of burnup balance for nuclear reactor fuel on the basis of γ-spectrometric determination of fission products

    International Nuclear Information System (INIS)

    Results are given of experimental investigations in one of the versions of the method for determination of the balance of nuclear fuel burnup process by means of the γ-spectrometry of fission products. In the version being considered a balance of the burnup process was determined on the base of 106Ru, 134Cs.Activity was measured by means of a γ-spectrometer with Ge counter. Investigations were done on the natural uranium metal fuel from the heavy-water moderated reactor of the first Czechoslovakian nuclear power plant A1 in Yaslovske Bohunice. Possibility was checked of determination of the fuel burnup depth as well as of the isotope ratio and content of plutonium. Results were compared with the control data which had been obtained on the base of the mass-spectrometry of U, Pu and Nd. The reasors for deviations were estimated in the cases when they were greater tan error in the control data

  4. Recent studies related to head-end fuel processing at the Hanford PUREX plant

    Energy Technology Data Exchange (ETDEWEB)

    Swanson, J.L.

    1988-08-01

    This report presents the results of studies addressing several problems in the head-end processing (decladding, metathesis, and core dissolution) of N Reactor fuel elements in the Hanford PUREX plant. These studies were conducted over 2 years: FY 1986 and FY 1987. The studies were divided into three major areas: 1) differences in head-end behavior of fuels having different histories, 2) suppression of /sup 106/Ru volatilization when the ammonia scrubber solution resulting from decladding is decontaminated by distillation prior to being discharged, and 3) suitability of flocculating agents for lowering the amount of transuranic (TRU) element-containing solids that accompany the decladding solution to waste. 16 refs., 43 figs.

  5. Application of a Monte Carlo Penelope code at diverse dosimetric problems in radiotherapy

    International Nuclear Information System (INIS)

    In the present communication it is presented the results of the simulation utilizing the Penelope code (Penetration and Energy loss of Positrons and Electrons) in several applications of radiotherapy which can be the radioactive sources simulation: 192 Ir, 125 I, 106 Ru or the electron beams simulation of a linear accelerator Siemens KDS. The simulations presented in this communication have been on computers of type Pentium PC of 100 throughout 300 MHz, and the times of execution were from some hours until several days depending of the complexity of the problem. It is concluded that Penelope is a very useful tool for the Monte Carlo calculations due to its great ability and its relative handling facilities. (Author)

  6. Intercomparison of radionuclides measurements in marine cockle flesh sample IAEA-134

    International Nuclear Information System (INIS)

    The results of an intercomparison exercise on a cockle flesh sample from Irish Sea, IAEA-134, designed for the determination of artificial and natural radionuclide levels, are reported. The data from 134 laboratories representing 49 countries have been evaluated. The following are the recommended values, with confidence intervals, for 40K, 60Co, 137Cs, and 239+240Pu (Reference date: 1 January 1992). Information values for 90Sr, 106Ru, 125Sb, 134Cs, 154Eu, 155Eu, 210Pb, 210Po, 226Ra, 228Ra, 228Th, 230Th, 232Th, 234U, 235U, 238U, 238Pu and 241Am are also reported. All the following values are expressed in Bq kg-1 (dry weight). (author)

  7. Intercomparison of radionuclide measurements in marine sediment sample IAEA-135

    International Nuclear Information System (INIS)

    The results of an intercomparison exercise on a marine sediment from Irish Sea, IAEA-135, designed for the determination of artificial and natural radionuclides levels, are reported. The data from 151 laboratories representing 51 countries have been evaluated. The following are the recommended values, with confidence intervals, for 40K, 60Co, 134Cs, 137Cs, 154Eu, 155Eu, 226Ra, 228Ra, 232Th,238Pu, 239+240Pu (Reference date: 1 January 1992). Information values for 57Co, 90Sr, 106Ru, 125Sb, 210Pb, 210Po, 228Th, 230Th, 234U, 235U, 238U and 241Am are also reported. All values are expressed in Bq kg-1 dry weight. (author)

  8. Chromatographic decontamination of medium-activity waste concentrates

    International Nuclear Information System (INIS)

    The chromatographic decontamination of a MAW concentrate was carried out in a laboratory plant in 1-l-batches in the following way: In order to purify the nitric MAW concentrate from its solid and organic contamination products, it is passed through a filter and an absorber (SM7) for organic species. Subsequently the purified solution runs on-line through all following columns. First the main activity carrier cesium (137Cs, 134Cs) is transferred to ammonium molybdate phosphate (AMP-1) by means of a newly developed fluidized bed process. In the further course, 125Sb is separated on metal oxides (Sb2O5, MnO2) and the three-valued actinides/lanthanides on an extraction-chromatographic CMPO column. Finally the remaining 106Ru and 60Co activities are separated on dimethylglyoximes (DMG) coated on active carbon. (orig./RB)

  9. Development of destructive methods of burn-up determination and their application on WWER type nuclear fuels

    International Nuclear Information System (INIS)

    Results are described of a cooperation between the Central Institute of Nuclear Research Rossendorf and the Radium Institute 'V.G. Chlopin' Leningrad in the field of destructive burn-up determination. Laboratory methods of burn-up determination using the classical monitors 137Cs, 106Ru, 148Nd and isotopes of heavy metals (U, Pu) as well as the usefulness of 90Sr, stable isotopes of Ru and Mo as monitors are dealt with. The analysis of the fuel components uranium (spectrophotometry, potentiometric titration, mass-spectrometric isotope dilution) and plutonium (spectrophotometry, coulometric titration, mass- and alpha-spectrometric isotope dilution) is fully described. Possibilities of increasing the reproducibility (automatic adjusting of measurement conditions) and the sensibility (ion impuls counting) of mass-spectrometric measurements are proposed and applied to a precise determination of Am and Cm isotopic composition. The methods have been used for burn-up analysis of spent WWER (especially WWER-440) fuel. (author)

  10. Application of a Monte Carlo Penelope code at diverse dosimetric problems in radiotherapy; Aplicacion del codigo Monte Carlo Penelope a diversos problemas dosimetricos en radioterapia

    Energy Technology Data Exchange (ETDEWEB)

    Sanchez, R.A.; Fernandez V, J.M.; Salvat, F. [Servicio de Oncologia Radioterapica. Hospital Clinico de Barcelona. Villarroel 170 08036 Barcelona (Spain)

    1998-12-31

    In the present communication it is presented the results of the simulation utilizing the Penelope code (Penetration and Energy loss of Positrons and Electrons) in several applications of radiotherapy which can be the radioactive sources simulation: {sup 192} Ir, {sup 125} I, {sup 106} Ru or the electron beams simulation of a linear accelerator Siemens KDS. The simulations presented in this communication have been on computers of type Pentium PC of 100 throughout 300 MHz, and the times of execution were from some hours until several days depending of the complexity of the problem. It is concluded that Penelope is a very useful tool for the Monte Carlo calculations due to its great ability and its relative handling facilities. (Author)

  11. Radioecological Impact of the French Nuclear Power Plants on the Marine Environment

    International Nuclear Information System (INIS)

    Since the end of the 1970s a global method has been developed and improved to characterise the radioecological impact of French nuclear power plants (PWRs) on the marine ecosystems. The environment of every nuclear plant is examined yearly, in addition to special studies carried out before plant operations begin and after each period of ten years. Three nuclear power plants are situated on the Channel coast (Flamanville, Paluel, Penly) and one on the North Sea coast (Gravelines). Near the power plants local radioecological impact is measurable and is essentially due to 58Co, 60Co and 110Agm. The monitoring of artificial gamma-emitter radioactivity in bioindicators (Fucus sp.) reveals the overall decline in releases from the four power stations in question (58Co, 60Co and 110Agm) as well as the more marked decrease in relation to the reprocessing plant at La Hague (106Ru, 60Co, 125Sb, 241Am). (author)

  12. A case of nevus of Ota associated with choroidal malignant melanoma%太田痣并发脉络膜黑素瘤

    Institute of Scientific and Technical Information of China (English)

    孙青苗; 蔡林; 张建中

    2010-01-01

    报告1例太田痣并发脉络膜黑素瘤.患者女,58岁.因右眼前黑影飘动、视物遮挡感伴视力下降6个月就诊.患者自14岁起右眼睑下方渐出现一淡青灰色斑片,随年龄增长而缓慢扩大,近5年来颜色明显加深.荧光素眼底血管造影及CT检查符合脉络膜黑素瘤表现,诊断为太田痣并发脉络膜黑素瘤.行~(106)Ru(钌)放射敷贴器置入术治疗.

  13. Study of the performance of ATLAS prototype detectors using analogue LHC front-end electronics

    CERN Document Server

    Riedler, P; Kaplon, J; Weilhammer, Peter

    2002-01-01

    The silicon strip detectors in the ATLAS experiment at LHC will be exposed to very high hadron fluences. In order to study the radiation damage effects ATLAS prototype detectors and small test detectors were irradiated to a fluence of 3 * 10/sup 14/ 24 GeV protons/cm/sup 2/. After irradiation, the detectors were annealed at 25 degrees C to simulate the damage foreseen after 10 years of ATLAS operation. The detectors were then connected to the SCT32A analogue front-end chips and tested with a /sup 106/Ru source. The performance of the irradiated detectors was compared to non-irradiated detectors from the same batch. The charge collection efficiency is discussed taking into account the electronic response of the readout chip and the ballistic deficit. (10 refs).

  14. Diffusion coefficients of fission products in the UO sub 2 kernel and pyrocarbon layer of BISO-coated fuel particles at extremely high temperatures

    Energy Technology Data Exchange (ETDEWEB)

    Hayashi, Kimio; Fukuda, Kousaku (Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan))

    1990-11-01

    Release of metal fission products from pyrocarbon (PyC) coated UO{sub 2} particles was studied by post-irradiation annealing at temperatures from 1600 to 2300deg C. Release of {sup 106}Ru and {sup 155}Eu was controlled by diffusion in the kernel at temperatures above 1800deg C, and their reduced diffusion coefficients in the kernel were very close to each other. The diffusion coefficient of Cs, D{sub Cs} (m{sup 2}/s), in the PyC layer was determined from the fractional release, as follows: D{sub Cs}=1.2x10{sup -3} exp(-4.12x10{sup 5} (J/mol)/RT), which was larger than that of Ce by an order of magnitude. The diffusion coefficients of fission products in the PyC layer was discussed in terms of their ionic radii and stability of their carbides. (orig.).

  15. Diffusion coefficients of fission products in the UO2 kernel and pyrocarbon layer of BISO-coated fuel particles at extremely high temperatures

    International Nuclear Information System (INIS)

    Release of metal fission products from pyrocarbon (PyC) coated UO2 particles was studied by post-irradiation annealing at temperatures from 1600 to 2300deg C. Release of 106Ru and 155Eu was controlled by diffusion in the kernel at temperatures above 1800deg C, and their reduced diffusion coefficients in the kernel were very close to each other. The diffusion coefficient of Cs, DCs (m2/s), in the PyC layer was determined from the fractional release, as follows: DCs=1.2x10-3 exp[-4.12x105 (J/mol)/RT], which was larger than that of Ce by an order of magnitude. The diffusion coefficients of fission products in the PyC layer was discussed in terms of their ionic radii and stability of their carbides. (orig.)

  16. Trace elements retained in washed nuclear fuel reprocessing solvents

    International Nuclear Information System (INIS)

    Analysis of purified TBP extractant from solvent extraction processes at Savannah River Plant showed several stable elements and several long-lived radioisotopes. Stable elements Al, Na, Br, Ce, Hg, and Sm are found in trace quantities in the solvent. The only stable metallic element consistently found in the solvent was Al, with a concentration which varies from about 30 ppM to about 10 ppM. The halogens Br and Cl appear to be found in the solvent systems as organo halides. Radionuclides found were principally 106Ru, 129I, 3H, 235U, and 239Pu. The 129I concentration was about 1 ppM in the first solvent extraction cycle of each facility. In the other cycles, 129I concentration varied from about 0.1 to 0.5 ppM. Both 129I and 3H appear to be in the organic solvent as a result of exchange with hydrogen

  17. Evaluation of artificial radioactivity of the north Western mediterranean sea and evaluation of the sanitary consequences

    International Nuclear Information System (INIS)

    The results of radiological measurements of the north west mediterranean observation network outline the level of artificial radionuclides coming from industrial seewages, 106Ru and from atmospheric fall out, 137Cs and sup(239+240)Pu measured on 3 differents types of bioindicators: Mytilus sp., Posidonia oceanica (L.) Del. and demersal fishes as Solea sp., Anguilla anguilla L., Conger conger L. Mytilus sp. is quite a perfect bioindicator of radionuclides contamination but must be linked with fishes sampling which muscles concentrate Cesium at higher level. The sanitary consequences for the waterside population involved by molluscs and fishes ingestion contamined by these 3 radionuclides lead to a fraction (10-5) of the annual dose limit recommanded by the ICRP 26

  18. A gauge for measuring the dose rate and activity of ophthalmic applicators

    International Nuclear Information System (INIS)

    A gauge is developed for determining the dose rate distribution and surface activity of ophthalmic brachytherapy applicators, particularly 106Ru applicators. A plastic Φ2x2 mm scintillator is used as the radiation detector, featuring a high pulse count rate, which results in a law 0.5% random error, due to good counting statistics. Automatic gain control of the photomultiplier tube (PMT) is achieved using a LED as the reference light source. The PMT operates in pulse mode. Long term gain variation due to fatigue of the PMT or ambient temperature variation is thus compensated for. The count rate error due to inaccurate setting of the high voltage supply of the PMT is 0.4%, and the instability error over 7 hours of continuous operation does not exceed 102%, peak-to-peak. (author)

  19. An iterative approach for TRIGA fuel burn-up determination using nondestructive gamma-ray spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Wang Tienko E-mail: tkw@faculty.nthu.edu.tw; Peir Jinnjer

    2000-01-01

    The purpose of this work is to establish a method for evaluating the burn-up values of the rod-type TRIGA spent fuel by using gamma-ray spectrometry of the short-lived fission products {sup 97}Zr/{sup 97}Nb, {sup 132}I, and {sup 140}La. Fuel irradiation history is not needed in this method. Short-lived fission-product activities were established by re irradiating the spent fuels in a nuclear reactor. Based on the measured activities, {sup 235}U burn-up values can be deduced by iterative calculations. The complication caused by {sup 239}Pu production and fission is also discussed in detail. The burn-up values obtained by this method are in good agreement with those deduced from the conventional method based on long-lived fission products {sup 137}Cs, {sup 134}Cs/{sup 137}Cs ratio and {sup 106}Ru/{sup 137}Cs ratio.

  20. An iterative approach for TRIGA fuel burn-up determination using nondestructive gamma-ray spectrometry

    International Nuclear Information System (INIS)

    The purpose of this work is to establish a method for evaluating the burn-up values of the rod-type TRIGA spent fuel by using gamma-ray spectrometry of the short-lived fission products 97Zr/97Nb, 132I, and 140La. Fuel irradiation history is not needed in this method. Short-lived fission-product activities were established by re irradiating the spent fuels in a nuclear reactor. Based on the measured activities, 235U burn-up values can be deduced by iterative calculations. The complication caused by 239Pu production and fission is also discussed in detail. The burn-up values obtained by this method are in good agreement with those deduced from the conventional method based on long-lived fission products 137Cs, 134Cs/137Cs ratio and 106Ru/137Cs ratio

  1. An iterative approach for TRIGA fuel burn-up determination using nondestructive gamma-ray spectrometry.

    Science.gov (United States)

    Wang, T K; Peir, J J

    2000-01-01

    The purpose of this work is to establish a method for evaluating the burn-up values of the rod-type TRIGA spent fuel by using gamma-ray spectrometry of the short-lived fission products 97Zr/97Nb, 132I, and 140La. Fuel irradiation history is not needed in this method. Short-lived fission-product activities were established by reirradiating the spent fuels in a nuclear reactor. Based on the measured activities, 235U burn-up values can be deduced by iterative calculations. The complication caused by 239Pu production and fission is also discussed in detail. The burn-up values obtained by this method are in good agreement with those deduced from the conventional method based on long-lived fission products 137Cs, 134Cs/137Cs ratio and 106Ru/137Cs ratio. PMID:10670930

  2. Determination of rare earth and uranium in reference biological materials certified by the method of neutron activation analysis; Determinacao de terras raras e de uranio em materiais biologicos de referencia certificados pelo metodo de analise por ativacao com neutrons

    Energy Technology Data Exchange (ETDEWEB)

    Pereira, Lais H.P.; Saiki, Mitiko, E-mail: laispaciulli@gmail.com, E-mail: mitiko@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2013-07-01

    The objective of this study was to evaluate the precision and accuracy of the determinations of Sc, La, Ce, Nd, Sm, Eu, Tb, Yb, Lu and U in certified reference materials (CRMs). To solve the problem of interference from fission products of U in the determination of lanthanides were obtained correction factors for this interference for {sup 140}La, {sup 141}Ce, {sup 143}Ce, {sup 153}Sm and {sup 147}Nd. The experimental procedure of Neutron Activation Analysis consisted of irradiating aliquots of each of the CRMs with synthetic standards of elements under thermal neutron flux of the IEA-R1 nuclear reactor, followed by gamma-ray spectrometry using a high-resolution hyperpurity GE detector. The analyzes of CRMs indicate good accuracy and precision of results, demonstrating the feasibility of applying of established procedure in NAA of elements studied in organic vegetable matrices.

  3. Nuclear Decay Data for the International Reactor Dosimetry Library for Fission and Fusion (IRDFF: Updated Evaluations of the Half-Lives and Gamma Ray Intensities

    Directory of Open Access Journals (Sweden)

    Chechev Valery P.

    2016-01-01

    Full Text Available Updated evaluations of the half-lives and prominent gamma ray intensities have been presented for 20 radionuclides – dosimetry reaction residuals. The new values of these decay characteristics recommended for the IRDFF library were obtained using the approaches and methodology adopted by the working group of the Decay Data Evaluation Project (DDEP cooperation. The experimental data published up to 2014 were taken into account in updated evaluations. The list of radionuclides includes 3H, 18F, 22Na, 24Na, 46Sc, 51Cr, 54Mn, 59Fe, 57Co, 60Co, 57Ni, 64Cu, 88Y, 132Te, 131I, 140Ba, 140La, 141Ce, 182Ta, 198Au.

  4. Solvent extraction using tetracycline as complexing agent Pt. 14

    International Nuclear Information System (INIS)

    The behaviour of tetracycline as an extracting agent for Sr, I, Ba, Mo, Tc, Zr, Nb, Cs, Ru, Te and U was studied and the influence of the acidity of the aqueous phase upon extraction of the elements mentioned was examined. Experiments were made to determine whether the species extracted into the organic phase is the complex formed between tetracycline and the elements considered and to determine the time of shaking necessary so that the equilibrium between the phases is attained. As a practical application, the possibility of using the tetracycline-benzyl alcohol system for separating the fission products sup(137)Cs, sup(140)La, sup(141)Ce, sup(103)Ru, sup(95)Nb from each other and from uranium is presented. The same study was made for sup(131)I, sup(99m)Tc, sup(99)Mo, sup(132)Te, sup(239)Np and uranium and the steps necassary for the separation of these elements are proposed. (author)

  5. Development of a cosmic veto gamma-spectrometer

    International Nuclear Information System (INIS)

    Cosmic radiation contributes significantly towards the background radiation measured by a gamma-spectrometer. A novel cosmic veto gamma-spectrometer has been developed that provides a mean background reduction of 54.5%. The system consists of plastic scintillation plates operated in time-stamp mode to detect coincident muon interactions within an HPGe gamma-spectrometer. The instrument is easily configurable and provides improved sensitivity for radionuclides indicative of nuclear weapons tests and reactor incidents, including 140Ba, 95Zr, 99Mo, 141Ce, 147Nd, 131I, 134Cs and 137Cs. This has been demonstrated for Comprehensive Nuclear-Test-Ban Treaty applications to obtain the required 140Ba MDA of 24 mBq within 2 days counting. Analysis of an air filter sample collected during the Fukushima incident indicates improved sensitivity compared to conventional gamma-spectrometers. (author)

  6. Counting efficiency for radionuclides decaying by beta and gamma-ray emission

    International Nuclear Information System (INIS)

    In this paper, counting efficiency vs figure of merit for beta and gamma-ray emitters has been computed. It is assumed that the decay scheme has only a gamma level and the beta-ray emission may be coincident with the gamma-rays or the internal-conversion electrons. The radionuclides tabulated are: 20O, 20F, 28Al, 35P,41Ar, 42K, 47Se, 62Fe, 66Cu, 81Ge, 86Rb, 104Rh, 108Ru, 112Pd, 121Sn(m), 122In, 129I, 141Ce, 142Pr, 151Sm, 170Tm, 171Tm, 194Os, 203Hg, 205Hg, 210Pb, 225Ra, 244Am(m). It has been assumed that the liquid is a toluene based scintillator solution in standard glass vials containing 10 cm3. (Author)

  7. Determination of critical assembly absolute power using post-irradiation activation measurement of week-lived fission products.

    Science.gov (United States)

    Košťál, Michal; Švadlenková, Marie; Milčák, Ján; Rypar, Vojtěch; Koleška, Michal

    2014-07-01

    The work presents a detailed comparison of calculated and experimentally determined net peak areas of longer-living fission products after 100 h irradiation on a reactor with power of ~630 W and several days cooling. Specifically the nuclides studied are (140)Ba, (103)Ru, (131)I, (141)Ce, (95)Zr. The good agreement between the calculated and measured net peak areas, which is better than in determination using short lived (92)Sr, is reported. The experiment was conducted on the VVER-1000 mock-up installed on the LR-0 reactor. The Monte Carlo approach has been used for calculations. The influence of different data libraries on results of calculation is discussed as well.

  8. Studies on inner bremsstrahlung from a few β-emitting isotopes

    International Nuclear Information System (INIS)

    Past experimental studies on the inner bremsstrahlung (IB) emission from the forbidden β transitions have shown marked deviations from the theoretical calculations of Lewis and Ford, Ford and Martin, Chang and Falkoff, Madansky and Gebhardt. In this paper we have re-analysed the data of IB emissions from four β-emitting isotopes, namely 89Sr, 141Ce, 111Ag and 99Tc, whose transitions are classified as forbidden. The raw experimental data already available in the literature are critically examined in the light of relevant statistics in order to arrive at meaningful conclusions. The unfolding of the IB spectra was done following the step-by-step procedure of Liden and Starfelt. The results obtained were different from those reported in the literature. (author)

  9. Seasonal variations in deposition and retention of cerium-141 and cesium-134 in cool desert vegetation

    International Nuclear Information System (INIS)

    Deposition velocities and retention half-times were measured for 141Ce and 134Cs aerosols on big sagebrush (Artemisia tridentata) and squirreltail bottlebrush (Elymus elymoides). These aerosols were released over a native community in southeast Idaho during each of three seasons -spring, summer, and winter -to study the effects of plant development and growth on deposition velocity and retention. Air concentrations during the release and vegetation concentration after the release were measured to determine deposition velocity. Friction velocity, roughness length, and particle size were measured to determine retention half-time. There was no significant difference between nuclides for deposition velocity and retention half-time. Species differences were significant (P -1 in spring, summer and winter, respectively. Big sagebrush values were 1.6, 1.6, and 1.0 mm s-1. Retention data indicated a rapid initial loss (half-times of 1-2 d) followed by a slower loss (half-times of several weeks). (Author)

  10. Distribution of gamma-emitting radionuclides in surface subtidal sediments near the Sellafield plant

    Energy Technology Data Exchange (ETDEWEB)

    Jones, D.G.; Roberts, P.D.; Miller, J.M.

    1988-08-01

    Detailed distributions of total gamma activity, /sup 137/Cs, /sup 106/Ru and /sup 95/Zr + /sup 95/Nb in surface seabed sediments near the Sellafield plant are presented. The results are derived from a towed seabed gamma-ray spectrometer survey in September, 1982. All the distributions are similar, with contours of equal activity parallel to the coast defining a 'ridge' of higher activity which is displaced northwards relative to the outfall. Nuclide concentrations decrease with increasing distance from Sellafield; rates of decrease being in the order Zr + Nb > Ru > Cs. This can be related to the levels of the nuclides discharged, their sorption characteristics and their half lives. The pattern of seabed activity seems to have been fairly stable over the period 1978-85, but there is evidence of a small northward shift. Concentrations of /sup 137/Cs and /sup 106/Ru in 1985 were considerably lower than in 1978 or 1982. This is explicable in terms of the fall in discharge levels allied, in the case of Ru, to its short half life and, for Cs, the desorption observed in laboratory experiments. Nuclide ratios in sediment samples yield apparent transit times for the transport of nuclides in the survey area of 1.7-3.7 years. These times are generally greater than those obtained from sediments in the more distant Solway Firth and Ravenglass Estuary. It is suggested that they reflect fairly intense bioturbation causing mixing of relatively recent effluent with that from earlier discharges. This is supported by structures observed in X-radiographs of box cores, an abundant burrowing benthos and by interpretations of nuclide profiles and radiocarbon dating of sediment cores by other workers. A lag effect, of up to two years across the survey area, appears to be superimposed on that due to mixing.

  11. Medical physics aspects of ophthalmic brachytherapy

    International Nuclear Information System (INIS)

    Intraocular melanoma is the most common primary malignancy of the eye. Radiation therapy using ophthalmic plaque has proved successful in the management of various ocular lesions. Although a few centres were using 90Sr/90Y plaques for shallow turtlours some years ago, eye plaque therapy was not a common practice in India. A revived interest in the use of eye plaque therapy and very high cost of imported sources has led to the development and production of 125I seed sources by the Radiopharmaceuticals Division, BARC. This report presents a brief description on the clinical, dosimetry and radiation safety aspects of 90Sr/90Y and 106Ru/106Rh beta ray and 125I gamma ray eye plaque applicators. This report has been divided in five Sections. Section I presents general introduction of ophthalmic brachytherapy including the structure of a human eye, types of ophthalmic plaques and characteristics of radioisotopes commonly used in such applications. A brief review of sources, applicators and dosimetry of 90Sr/90Y and 106Ru/106Rh beta and 125I gamma ophthalmic plaques are given in Section II and Section III, respectively. Section IV contains the single seed dosimetry data of BARC OcuProsta 125I seed as well as dosimetry data of typical eye plaques loaded with BARC OcuProsta 125I seed. Quality assurance and radiation safety aspects of these eye applicators are described in Section V. A proforma of the application required to be filled in by the user institution for obtaining regulatory consent to start eye plaque therapy has also been appended to this report. (author)

  12. The Influence of Body Size and Food Preparation Practices on the Uptake and Loss of Radionuclides in Cumbrian Winkles

    International Nuclear Information System (INIS)

    It has been suggested that larger winkles may show higher concentrations of radioactivity and that critical group members, when providing MAFF with sub-samples of winkles they have collected, retain the largest organisms for consumption. If both these hypotheses are true, this could imply higher doses than typically estimated. Conversely, it is assumed that winkles are consumed immediately following collection, without gut clearance, which may overestimate the consumption dose. Results obtained in this study indicate the following. (1) Inverse correlations are observed between concentration and body size for 106Ru and 241Am. A positive relationship is observed for 60Co. Although concentrations of 137Cs decrease with increasing body size the negative correlation is not significant, while 110Agm concentration is independent of body size. (2) There is no evidence that critical group consumers retain larger organisms. In any case, consuming larger or smaller winkles, over the size range tested, probably does not affect dose uptake by more than 10%. (3) Concentrations of plutonium and americium decline to 50% of original by soaking winkles for 18 h. Concentrations of caesium are also reduced. (4) Concentrations of 106Ru, 110Agm and 60Co are not reduced by soaking. Overall, current approaches to deriving consumption doses are not likely to suffer from selection bias. Overnight soaking of winkles in saline solution could decrease radiation doses to consumers by a factor of nearly 2; provided that the fractional gut transfer of activity remaining is unaffected. This last assumption, however is questionable and the current approach should provide a 'reasonably conservative' dose estimate appropriate to critical group studies. (author)

  13. Retrospective dosimetry of an accidental intake case of radioruthenium-106 at the Tokai reprocessing plant

    International Nuclear Information System (INIS)

    On November 30, 1978, two workers in the acid recovery cell of the nuclear spent fuel reprocessing plant of JAEA-NFCEL were involved in an accident in which they became unconscious due to lack of oxygen. They were rescued immediately by other workers and were given artificial respiration to restore their normal breathing. Subsequent measurements by the whole-body counter showed that they were contaminated internally with 106Ru. Prolonged lung monitoring was carried out for one of them. A significantly high activity of 106Ru was obtained in the lung monitoring on the day of the accident. The physicochemical characteristics of the incorporated radioactive materials were not observed. In order to perform more reasonable internal dose assessment, the interpretation of the bioassay datasets of the worker was made based on the guideline demonstrated in the EU project IDEAS. The effective half-life of the materials in the lungs was determined to be 140 days which leads to the default Type S absorption type in the HRTM and the f1 value was estimated to be less than 0.005 which is one-tenth of the default value. Simultaneous intakes via inhalation and ingestion were also suggested from several pieces of evidence although pure inhalation was assumed for internal dose assessment at the time of the accident. The aerosol size of the materials was not determined due to a lack of information if assuming simultaneous intakes; however, the resulting committed effective dose was about 1 mSv and its variation was small against the aerosol size ranging from 1 μm to 20 μm. (author)

  14. Germanium junction detectors. Theoretical and practical factors governing their use in radiation spectrometry; Detecteurs a jonction au germanium. Elements theoriques et pratiques pour l'utilisation en spectrometrie de rayonnements

    Energy Technology Data Exchange (ETDEWEB)

    Hors, M.; Philis, C. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1967-07-01

    Semi-conductor detectors have recently greatly increased the possibilities available to nuclear spectroscopists for the study of {alpha}, {beta} and {gamma} radiations. Their use in radio-chemistry has encouraged us to study their principle, their mechanism and also the conditions under which they can be used. The first part, which is theoretical, consists of a summary of what should be known concerning the best use of junction detectors, in particular Ge (Li) detectors. The second part, which is experimental, summarizes the laboratory work carried out over a period of one year on Ge (Li) detectors. Stress is laid on the possibilities presented by the use of these detectors as photo-electric spectrometers, and also on the precautions required. Amongst the numerous results presented, the resolution of 2.52 keV obtained for the {gamma} radiation of 145.5 keV for {sup 141}Ce may be particularly noted. (authors) [French] Les detecteurs a semi-conducteurs ont recemment accru les possibilites offertes aux spectroscopistes nucleaires pour l'etude des radiations {alpha}, {beta}, {gamma}. Leurs utilisations en radiochimie nous ont incite a en etudier le principe, le mecanisme et d'autre part les conditions d'emploi. La premiere partie, theorique, rappelle l'essentiel de ce qu'il est utile de connaitre pour une utilisation optimale des detecteurs a jonctions et en particulier des detecteurs Ge (Li). La deuxieme partie, experimentale, resume les travaux realises au laboratoire pendant un an avec des detecteurs Ge (Li). Nous insistons sur les possibilites offertes et les precautions a prendre dans l'utilisation de ces detecteurs comme spectrometres photoelectriques. Parmi les nombreux resultats presentes, citons la resolution de 2,52 keV obtenue pour le rayonnement {gamma} de 145 f5 keV du {sup 141}Ce. (auteurs)

  15. Improved estimate of the cross section for inverse beta decay

    CERN Document Server

    Ankowski, Artur M

    2016-01-01

    The hypothesis of the conserved vector current, relating the vector weak and isovector electromagnetic currents, plays a fundamental role in quantitative description of neutrino interactions. Despite being experimentally confirmed with great precision, it is not fully implemented in existing calculations of the cross section for inverse beta decay, the dominant mechanism of antineutrino scattering at energies below a few tens of MeV. In this article, I estimate the corresponding cross section and its uncertainty, ensuring conservation of the vector current. While converging to previous calculations at energies of several MeV, the obtained result is appreciably lower and predicts more directional positron production near the reaction threshold. These findings suggest that in the current estimate of the flux of geologically produced antineutrinos the 232Th and 238U components may be underestimated by 6.1 and 3.7%, respectively. The proposed search for light sterile neutrinos using a 144Ce--144Pr source is predi...

  16. Measurement by γ spectrometry of specific activities of radioisotopes present in vegetal ashes. Study of variations of the ambient radioactivity level in the Grenoble transverse valley from March 1966 to August 1968

    International Nuclear Information System (INIS)

    The first part of this report addresses the dosimetry of γ emitting radio-elements which are present in vegetal samples. The dose measurements were performed by spectrometry and results were processed by using a least square method. The second part reports works performed in the Grenoble transverse valley by using the same techniques. Radioactivity fluctuations of various radio-elements (40K, 54Mn, 95Zr + 95Nb, 103Ru + 106Rh, 137Cs, 137Ba, 140Ba + 140La, 144Ce + 144Pr) in various vegetal species, in water and in sediments have been monitored in seven points of the Isere river banks, upstream and downstream the city of Grenoble, from March 1966 to August 1968. Fluctuations observed for each radio-element are explained by comparison with physiologic, hydrologic and atmospheric climate conditions. The principles of a systematic control of a site for the detection of possible radioactive pollutions are then defined

  17. A high precision calorimeter for the SOX experiment

    Science.gov (United States)

    Papp, L.; Agostini, M.; Altenmüller, K.; Appel, S.; Caminata, A.; Cereseto, R.; Di Noto, L.; Farinon, S.; Musenich, R.; Neumair, B.; Oberauer, L.; Pallavicini, M.; Schönert, S.; Testera, G.; Zavatarelli, S.

    2016-07-01

    The SOX (Short distance neutrino Oscillations with BoreXino) experiment is being built to discover or reject eV-scale sterile neutrinos by observing short baseline oscillations of active-to-sterile neutrinos [1]. For this purpose, a 100 kCi 144Ce-144Pr antineutrino generator (CeSOX) will be placed under the BOREXINO detector at the Laboratori Nazionali del Gran Sasso. Thanks to its large size and very low background, BOREXINO is an ideal detector to discover or reject eV-scale sterile neutrinos. To reach the maximal sensitivity, we aim at determining the neutrino flux emitted by the antineutrino generator with a calorimeter, which is designed to measure the source-generated heat with high accuracy.

  18. The SOX experiment in the neutrino physics

    Science.gov (United States)

    Di Noto, L.; Agostini, M.; Althenmüller, K.; Bellini, G.; Benziger, J.; Berton, N.; Bick, D.; Bonfini, G.; Bravo-Berguño, D.; Caccianiga, B.; Cadonati, L.; Calaprice, F.; Caminata, A.; Cavalcante, P.; Chavarria, A.; Chepurnov, A.; Cribier, M.; DAngelo, D.; Davini, S.; Derbin, A.; Durero, M.; Empl, A.; Etenko, A.; Farinon, S.; Fischer, V.; Fomenko, K.; Franco, D.; Gabriele, F.; Gaffiot, J.; Galbiati, C.; Gazzana, S.; Ghiano, C.; Giammarchi, M.; Göger-Neff, M.; Goretti, A.; Grandi, L.; Gromov, M.; Hagner, C.; Houdy, Th.; Hungerford, E.; Ianni, Al.; Ianni, An.; Jonquères, N.; Kobychev, V.; Korablev, D.; Korga, G.; Kryn, D.; Lasserre, T.; Laubenstein, M.; Lehnert, T.; Lewke, T.; Litvinovich, E.; Lombardi, F.; Lombardi, P.; Ludhova, L.; Lukyanchenko, G.; Machulin, I.; Manecki, S.; Maneschg, W.; Marcocci, S.; Maricic, J.; Meindl, Q.; Mention, G.; Meroni, E.; Meyer, M.; Miramonti, L.; Misiaszek, M.; Montuschi, M.; Mosteiro, P.; Musenich, R.; Muratova, V.; Oberauer, L.; Obolensky, M.; Ortica, F.; Otis, K.; Pallavicini, M.; Papp, L.; Perasso, L.; Perasso, S.; Pocar, A.; Ranucci, G.; Razeto, A.; Re, A.; Romani, A.; Rossi, N.; Saldanha, R.; Salvo, C.; Schönert, S.; Scola, L.; Simgen, H.; Skorokhvatov, M.; Smirnov, O.; Sotnikov, A.; Sukhotin, S.; Suvorov, Y.; Tartaglia, R.; Testera, G.; Veyssière, C.; Vivier, M.; Vogelaar, R. B.; von Feilitzsch, F.; Wang, H.; Winter, J.; Wojcik, M.; Wright, A.; Wurm, M.; Zaimidoroga, O.; Zavatarelli, S.; Zuber, K.; Zuzel, G.

    2015-01-01

    SOX (Short distance neutrino Oscillations with BoreXino) is a new experiment that takes place at the Laboratori Nazionali del Gran Sasso (LNGS) and it exploits the Borexino detector to study the neutrino oscillations at short distance. In different phases, by using two artificial sources 51Cr and 144Ce-144Pr, neutrino and antineutrino fluxes of measured intensity will be detected by Borexino in order to observe possible neutrino oscillations in the sterile state. In this paper an overview of the experiment is given and one of the two calorimeters that will be used to measure the source activity is described. At the end the expected sensitivity to determine the neutrino sterile mass is shown.

  19. Measurement of leached hulls

    International Nuclear Information System (INIS)

    Leached hulls are the short lengths of fuel rod cladding and fuel element hardware which constitute a major waste product of a reprocessing plant employing a chop-and-leach head-end process. The small, undissolved fuel residue (0.1 to 1.0% of original fuel content) which is discarded with this waste must be measured for safeguards, material accountability, and process control reasons. This report gives a critical analysis of hull measurement techniques involving the analysis of fission product gamma rays, spontaneous fission neutrons from curium, and delayed neutron activation. Major emphasis is given to the measurement of 2186-keV gamma rays from 144Ce--144Pr. A detailed description of typical leached hull characteristics is presented at the beginning of the report. An extensive review of experience gained from existing hull measurement systems in the United Kingdom, France, Japan, Germany, Italy, and the United States is presented

  20. Source self-attenuation in ionization chamber measurements of (57)Co solutions.

    Science.gov (United States)

    Cessna, Jeffrey T; Golas, Daniel B; Bergeron, Denis E

    2016-03-01

    Source self-attenuation for solutions of (57)Co of varying density and carrier concentration was measured in nine re-entrant ionization chambers maintained at NIST. The magnitude of the attenuation must be investigated to determine whether a correction is necessary in the determination of the activity of a source that differs in composition from the source used to calibrate the ionization chamber. At our institute, corrections are currently made in the measurement of (144)Ce, (109)Cd, (67)Ga, (195)Au, (166)Ho, (177)Lu, and (153)Sm. This work presents the methods used as recently applied to (57)Co. A range of corrections up to 1% were calculated for dilute to concentrated HCl at routinely used carrier concentrations.

  1. Lifetime tumor risk coefficients for beagle dogs that inhaled cerium-144 chloride

    Energy Technology Data Exchange (ETDEWEB)

    Boecker, B.B.; Hahn, F.F.; Griffith, W.C. [and others

    1995-12-01

    Reported here is one of the life-span radionuclide toxicology studies being conducted at ITRI in Beagle dogs. These studies are examining the life-span health risks of inhaled {Beta}-, {gamma}- and {alpha}-emitting radionuclides to expand available knowledge on these risks especially for the many cases for which human data are not available. The outcomes of these studies are providing important information on dosimetry and dose-response relationships for these inhaled radionuclides and the relative importance of a broad range of dose- and effect-modifying factors. A number of these studies are currently coming to completion. Much of the ITRI effort is being directed to final reviews of the dosimetric, clinical, and pathologic results and writing summary manuscripts. Radiation doses and effects in tissues adjacent to bone, specifically those of epithelial or marrow origin, should be considered when determining risks from internally deposited, bone-seeking radionuclides such as {sup 144}Ce.

  2. Radionuclides in plankton from the South Pacific Basin

    International Nuclear Information System (INIS)

    We have initiated an investigation of the utility of marine plankton as bioconcentrating samplers of low-level marine radioactivity in the southern hemisphere. A literature review has shown that both freshwater and marine plankton have trace element and radionuclide concentration factors (relative to water) of up to 104. We participated in Operations Deepfreeze 1981 and 1982, collecting a total of 48 plankton samples from the USCGC Glacier on its Antarctic cruises. Battelle Pacific Northwest Laboratories sampled air, water, rain, and fallout. We were able to measure concentrations in plankton of the naturally-occurring radionuclides 7Be, 40K, and the U and Th series, and we believe that we have detected low levels of 144Ce and 95Nb in seven samples ranging as far south as 680. Biological identification of the plankton suggests a possible correlation between radionuclide concentration and the protozoa content of the samples. 7 references, 5 figures

  3. Identification of levels in neutron-rich 145Ce and 147Ce nuclei

    International Nuclear Information System (INIS)

    High-spin structures in the neutron-rich nuclei 145Ce and 147Ce produced in the spontaneous fission of 252Cf have been investigated by prompt γ-ray spectroscopy. A collective band structure in 145Ce is identified. Several sidebands along with the new high-spin states in 147Ce are also identified. Particle-plus-rotor model calculations indicate that the yrast bands in 145Ce and 147Ce most probably originate from coupling of the νi13/2 orbital to the ground states of 144Ce and 146Ce. The ground state configurations of 145,147Ce are (νh9/2+νf7/2) and νh9/2, respectively. (c) 1999 The American Physical Society

  4. Radiocaesium forms in soil - problems of experimental determination

    International Nuclear Information System (INIS)

    A method for determining Cs form in soil is proposed based on the comparison of the experimental data on desorption of Cs radionuclide from the soil contaminated as a result of the Chernobyl accident and from the soil samples on which Cs was absorbed in laboratory (Cs was introduced in ionic form in solution). The data obtained on desorption of Cs from different soils show that Cs radionuclide is present in the soil contaminated as a result of the Chernobyl accident predominantly in an ionic form (sorbed on the different soil fractions). It has also been found that the ratio of 144Ce/137Cs radionuclides is much higher in solution than in the soil. At the same time the data on sorption of Cs and Ce radionuclides on different soils from solution 0.1M HCI + 0.1M KCI + 0.1M FeCI3 show that the sorption ability of Cs is higher than the sorption ability of Ce for all the soil types investigated. Hence, it can be assumed that the mechanism of the radionuclides extraction is desorption rather than dissolution of the matrix particles, since in the letter case extraction value of the radionuclides would not be different. The fact that the ratio of 144Ce/137Cs radionuclides in solution remains higher than in soil independent on the distance from the Chernobyl NPP indicates that the form of the radionuclides does not change with the distance from the reactor. In order to determine what type of molecules Cs radionuclide can be bound to in soil the experiments on sorption of Cs on sandy soil in the presence of humic acid in solution has been carried out. The data obtained show that the presence of humic acids has none or little effect on the sorption of Cs. This indicates that interaction of Cs radionuclides with humic acid is week and these molecules can not be responsible for binding Cs in soil. (author)

  5. EML Surface Air Sampling Program, 1990--1993 data

    International Nuclear Information System (INIS)

    Measurements of the concentrations of specific atmospheric radionuclides in air filter samples collected for the Environmental Measurements Laboratory's Surface Air Sampling Program (SASP) during 1990--1993, with the exception of April 1993, indicate that anthropogenic radionuclides, in both hemispheres, were at or below the lower limits of detection for the sampling and analytical techniques that were used to collect and measure them. The occasional detection of 137Cs in some air filter samples may have resulted from resuspension of previously deposited debris. Following the April 6, 1993 accident and release of radionuclides into the atmosphere at a reprocessing plant in the Tomsk-7 military nuclear complex located 16 km north of the Siberian city of Tomsk, Russia, weekly air filter samples from Barrow, Alaska; Thule, Greenland and Moosonee, Canada were selected for special analyses. The naturally occurring radioisotopes that the authors measure, 7Be and 210Pb, continue to be detected in most air filter samples. Variations in the annual mean concentrations of 7Be at many of the sites appear to result primarily from changes in the atmospheric production rate of this cosmogenic radionuclide. Short-term variations in the concentrations of 7Be and 210Pb continued to be observed at many sites at which weekly air filter samples were analyzed. The monthly gross gamma-ray activity and the monthly mean surface air concentrations of 7Be, 95Zr, 137Cs, 144Ce, and 210Pb measured at sampling sites in SASP during 1990--1993 are presented. The weekly mean surface air concentrations of 7Be, 95Zr, 137Cs, 144Ce, and 210Pb for samples collected during 1990--1993 are given for 17 sites

  6. Toxicity of inhaled beta-emitting radionuclides: an experimental approach

    International Nuclear Information System (INIS)

    An experimental approach to evaluation of the toxicity of inhaled beta-emitting radionuclides in laboratory animals is described. These radionuclides are being studied in both relatively soluble (90SrCl2, 144CeCl3, 91YCl3 or 137CsCl) and relatively insoluble aerosol forms (90Y, 91Y, 144Ce or 90Sr in fused aluminosilicate particles). Initial lung or whole-body radionuclide burdens were selected to result in early deaths due to severe lesions at the highest exposure levels, and more subtle changes, such as neoplasia, at the lower levels. The organs affected vary depending on the solubility and chemical characteristics of the isotope. For radionuclides inhaled in relatively soluble forms, long-term effects have been seen in the liver, skeleton, respiratory tract and other tissues. In contrast, long-term effects seen in the dogs exposed to relatively insoluble forms have been mainly associated with the lung and contiguous tissues. In all experiments, emphasis is placed on an evaluation of the influence of radiation dose rate and total dose on the resulting dose-response relationship. Over the mid-range of exposure levels, it will be possible to compare the radiation dose and biological response relationships for the several radioactive aerosols with their different radiation dose patterns. These studies with young adult dogs are complemented with comparable studies in other species (mice, rats and Syrian hamsters) and with animals of different ages (immature, aged). This basic approach, with emphasis on factors that alter the resulting radiation dose pattern, offers the maximum likelihood of meeting the continuing, and not always predictable, needs for information on the toxicity of inhaled beta-emitting radionuclides that may be encountered in nuclear industry operations

  7. Toxicity of inhaled beta-emitting radionuclides: an experimental approach

    International Nuclear Information System (INIS)

    An experimental approach to evaluation of the toxicity of inhaled beta-emitting radionuclides in experimental animals is described. Graded levels of these radionuclides are being studied in both relatively soluble (90SrCl2, 144CeCl3, 91YCl3, 137CsCl) and relatively insoluble forms (90Y, 91Y, 144Ce and 90Sr in fused clay particles). Initial lung or whole-body activity burdens were selected to result in early deaths due to severe lesions at the highest levels, deaths at later times with moderate to marked pathologic changes and more subtle changes such as neoplasia at the lower levels. The organs affected vary depending on the solubility and chemical characteristics of the isotope. For radionuclides inhaled in relatively soluble forms, long-term effects have been seen in the liver, skeleton, and other tissues in addition to some pulmonary effects. In contrast, long-term effects seen in the dogs exposed to relatively insoluble forms have been mainly associated with the lung and contiguous tissues. In the latter experiments, emphasis is placed on an evaluation of the influence of radiation dose rate and total dose on the resulting dose-response relationship. Over the mid-range of the relationship between radiation dose and biological response, it will be possible to compare the relationships for the several radioactive aerosols with their different radiation dose patterns. These studies with young adult dogs are complemented with comparable studies in other species (mice, Syrian hamsters) and with animals of different ages (immature, aged). This basic approach, with emphasis on factors that alter the resulting radiation dose pattern, offers the maximum likelihood of meeting the continuing, and not always predictable, needs for information on the toxicity of inhaled beta-emitting radionuclides that may be encountered in nuclear industry operations. (U.S.)

  8. EML Surface Air Sampling Program, 1990--1993 data

    Energy Technology Data Exchange (ETDEWEB)

    Larsen, R.J.; Sanderson, C.G.; Kada, J.

    1995-11-01

    Measurements of the concentrations of specific atmospheric radionuclides in air filter samples collected for the Environmental Measurements Laboratory`s Surface Air Sampling Program (SASP) during 1990--1993, with the exception of April 1993, indicate that anthropogenic radionuclides, in both hemispheres, were at or below the lower limits of detection for the sampling and analytical techniques that were used to collect and measure them. The occasional detection of {sup 137}Cs in some air filter samples may have resulted from resuspension of previously deposited debris. Following the April 6, 1993 accident and release of radionuclides into the atmosphere at a reprocessing plant in the Tomsk-7 military nuclear complex located 16 km north of the Siberian city of Tomsk, Russia, weekly air filter samples from Barrow, Alaska; Thule, Greenland and Moosonee, Canada were selected for special analyses. The naturally occurring radioisotopes that the authors measure, {sup 7}Be and {sup 210}Pb, continue to be detected in most air filter samples. Variations in the annual mean concentrations of {sup 7}Be at many of the sites appear to result primarily from changes in the atmospheric production rate of this cosmogenic radionuclide. Short-term variations in the concentrations of {sup 7}Be and {sup 210}Pb continued to be observed at many sites at which weekly air filter samples were analyzed. The monthly gross gamma-ray activity and the monthly mean surface air concentrations of {sup 7}Be, {sup 95}Zr, {sup 137}Cs, {sup 144}Ce, and {sup 210}Pb measured at sampling sites in SASP during 1990--1993 are presented. The weekly mean surface air concentrations of {sup 7}Be, {sup 95}Zr, {sup 137}Cs, {sup 144}Ce, and {sup 210}Pb for samples collected during 1990--1993 are given for 17 sites.

  9. The distribution of gamma-emitting radionuclides in surface subtidal sediments near the Sellafield plant

    Science.gov (United States)

    Jones, D. G.; Roberts, P. D.; Miller, J. M.

    1988-08-01

    Detailed distributions of total gamma activity, 137Cs, 106Ru and 95Zr + 95Nb in surface seabed sediments near the Sellafield plant are presented. The results are derived from a towed seabed gamma-ray spectrometer survey in September, 1982. All the distributions are similar, with contours of equal activity parallel to the coast defining a 'ridge' of higher activity which is displaced northwards relative to the outfall. This pattern appears to be largely a response to the transport of particle-associated radioeffluent modified in places by the type of seabed sediment present. At greater distance from Sellafield, the uptake of nuclides from solution seems to be more important. Nuclide concentrations decrease with increasing distance from Sellafield; rates of decrease being in the order Zr + Nb > Ru > Cs. This can be related to the levels of the nuclides discharged, their sorption characteristics and their half lives. The pattern of seabed activity seems to have been fairly stable over the period 1978 - 1985, but there is evidence of a small northward shift. Concentrations of 137Cs and 106Ru in 1985 were considerably lower than in 1978 or 1982. This is explicable in terms of the fall in discharge levels allied, in the case of Ru, to its short half life and, for Cs, the desorption observed in laboratory experiments. Nuclide ratios in sediment samples yield apparent transit times for the transport of nuclides in the survey area of 1·7 - 3·7 years. These times are generally greater than those obtained from sediments in the more distant Solway Firth and Ravenglass Estuary. It is suggested that they reflect fairly intense bioturbation causing mixing of relatively recent effluent with that from earlier discharges. This is supported by structures observed in X-radiographs of box cores, an abundant burrowing benthos and by interpretations of nuclide profiles and radiocarbon dating of sediment cores by other workers. A lag effect, of up to two years across the survey area

  10. Volatility of ruthenium-106, technetium-99, and iodine-129, and the evolution of nitrogen oxide compounds during the calcination of high-level, radioactive nitric acid waste

    International Nuclear Information System (INIS)

    The nitrate anion is the predominant constituent in all high-level nuclear wastes. Formic acid reacts with the nitrate anion to yield noncondensable, inert gases (N2 or N2O), which can be scrubbed free of 106Ru, 129I, and 99Tc radioactivities prior to elimination from the plant by passing through HEPA filters. Treatment of a high-level authentic radioactive waste with two moles of formic acid per mole of nitrate anion leads to a low RuO4 volatility of about 0.1%, which can be reduced to an even lower level of 0.007% on adding a 15% excess of formic acid. Without pretreatment of the nitrate waste with formic acid, a high RuO4 volatility of approx. 35% is observed on calcining a 4.0 N HNO3 solution in quartz equipment at 3500C. The RuO4 volatility falls to approx. 1.0% on decreasing the initial HNO3 concentration to 1.0 N or lower. It is postulated that thermal denitration of a highly nitrated ruthenium complex leads to the formation of volatile RuO4, while decarboxylation of a ruthenium-formate complex leads to the formation of nonvolatile RuO2. Wet scrubbing with water is used to remove RuO4 from the off-gas stream. In all glass equipment, small amounts of particulate RuO2 are formed in the gas phase by decomposition of RuO4. The 99Tc volatility was found to vary from 0.2 to 1.4% on calcining HNO3 and HCOOH (formic acid) solutions over the temperature range of 250 to 6000C. These unexpectedly low volatilities of 99Tc are correlated to the high thermal stability limits of various metal pertechnetates and technetates. Iodine volatilities were high, varying from a low of 30% at 3500C to a high of 97% at 6500C. It is concluded that with a proper selection of pretreatment and operating conditions the 106Ru and 99Tc activities can be retained in the calcined solid with recycle of the wet scrubbing solution

  11. Exposure of the population of countries within the European Union to radioactivity in the mediterranean sea: Project MARINA-MED

    International Nuclear Information System (INIS)

    The discharges examined in the Project MARINA-MED were from nuclear installations in France, Italy and Spain, over the period 1980-1991; those from the Marcoule fuel reprocessing plant were found to contribute most of the collective dose arising from radioactivity in the Mediterranean Sea. Over 90% of beta-gamma discharges were of tritium and the remainder comprised some 80% 106Ru + 106Rh, 7% 90Sr + 90Y, 6% 137Cs, and 1% each of 134Cs, 58Co and 54Mn. The alpha emitters were dominated by 241Am, 239+240Pu and natural uranium, each representing 30% of the total. The contribution from Chernobyl had largely disappeared by 1990, except in the northern Aegean Sea, where continuing input came from the Black Sea. The corresponding exposure of the critical group in the Mediterranean Sea area from 137Cs (for an annual consumption of 73 kg fish and 35 kg shellfish) was estimated to be 7.5 μSv in 1990; the exposure of the critical group in the Black Sea area would have been about 40 μSv. These values are much lower than that estimated for 210Po, which corresponds to about 0.5 mSv. Data were obtained on catches and consumption rates of fish, crustaceans and molluscs for the relevant countries within the European Union, including import and export. Using data from the Food and Agriculture Organization of the United Nations, it was possible to extend the data to other countries bordering the Mediterranean Sea. Peak annual collective doses were estimated at less than 0.2 man·Sv for the period considered. For discharges over the entire period (1980-1991) the total collective dose commitment, truncated at 500 years, was estimated to be about 2 man·Sv. The most significant radionuclides, especially in the first few years, were found to be 106Ru (0.76 man·Sv) and 241Am (0.25 man·Sv). (author). 7 refs, 3 tabs

  12. Chromatographic purification of neutron capture molybdenum-99 from cross-contaminant radionuclides

    International Nuclear Information System (INIS)

    Technetium-99m is called the work horse, for many reasons, in nuclear medicine diagnostic purposes. It is produced as the β-decay of 99Mo radionuclide. Molybdenum-99 gel type generators are considered as a suitable alternative of the conventional chromatographic alumina columns loaded with fission molybdenum-99. 99Mo neutron-capture is cross-contaminated with radionuclides originated from activation of chemical impurities in the Mo target such 60C0, 65Zn, 95Zr, 175Hf, 181Hf, 86Rb, 134Cs, 141Ce, 152Eu, 140La,51Cr, 124Sb,46Sc, 54Mn, 59Fe and / or fast neutrons interactions with the stable isotopes of molybdenum such as 92mNb, 95Nb and 95Zr. To prevent contamination of the eluted 99mTc, successive purification methods were made. After complete dissolution of the irradiated target wrapped with thin Al foil in 5 M NaOH solution, hydrogen peroxide was added to start precipitation of Fe(OH)3. The formed Fe (III) minerals allow complete elimination of some radio contaminants from the molybdate solute such as 152Eu, 140La,141Ce, 45Mn and 92mNb in addition to partial elimination of 46Sc, 60Co and 59Fe radionuclides. The remaining supernatant was acidified by concentrated nitric acid to ph 9.5 for precipitation of Al(OH)3 with complete elimination of radio contaminants such as 95Zr 175Hf, 181Hf, 65Zn, 124Sb, 51Cr, 46Sc, 60Co and 59Fe. 134Cs and 86Rb radionuclides were not affected by precipitation of Fe(OH)3 or Al(OH)3. Chromatographic column of potassium nickel hexacyanoferrate (II) (KNHCF) has high affinity towards elimination of 134Cs and 86Rb radionuclides. Highly pure molybdate-99Mo solution was processed for preparation of zirconium molybdate gel generator with 99mTc eluate of high radionuclidic, radiochemical and chemical purity suitable for use in medical purposes.

  13. Implications of sedimentological and hydrological processes on the distribution of radionuclides: The example of a salt marsh near Ravenglass, Cumbria

    Science.gov (United States)

    Carr, A. P.; Blackley, M. W. L.

    1986-05-01

    This paper summarizes sedimentological and hydrological studies at a salt marsh site on the north bank of the River Esk near Ravenglass which have a bearing on the fate of the low-level radioactive effluent from the reprocessing facility at Sellafield, Cumbria. A range of techniques has been used including electromagnetic distance measurement (EDM) and pore water pressure studies. The results show that: (a) Over a two-year period there were no significant net changes in salt marsh creek level, although shorter-term (probably seasonal) fluctuations, of the order of 2 cm, occurred. These were attributed to expansion of clay particles during the winter months. Nearby, however, there were vertical changes of the order of 1 m due to erosion. (b) Pore water pressures indicated a dynamic situation with very rapid responses both to tidal fluctuations and to rainfall. During neap tides there was clear evidence for water seeping upwards from the underlying clay/sand interface. Shortlived radionuclides ( 95Zr/95Nb and 106Ru) were detected in this zone. (c) Soil polygons, once initiated by desiccation, thereafter provide preferential routes for water (and radionuclides) to the sub-surface sediment. These, and other results, are discussed in the context of previous studies. It is concluded that the complexity of the estuarine environment results in most data being site specific.

  14. Distribution of radionuclides in mussels, winkles and prawns: Pt. 1; Study of organisms under environmental conditions using conventional radio-analytical techniques

    Energy Technology Data Exchange (ETDEWEB)

    McDonald, P. (Scottish Research Reactor Centre, East Kilbride (United Kingdom)); Baxter, M.S.; Fowler, S.W. (International Atomic Energy Agency, Monaco (Monaco). Marine Environment Lab.)

    1993-01-01

    Mussels (Mytilus edulis) and winkles (Littorina littorea), collected from Ravenglass, Cumbria, England in the vicinity of the British Nuclear Fuels plc nuclear reprocessing plant at Sellafield, and prawns (Palaemon serratus), landed nearby at Whitehaven, have been investigated to determine the distributions of [alpha]-emitting ([sup 210]Po, [sup 238]Pu, [sup 239] [sup +] [sup 240]Pu, [sup 241]Am) and [gamma]-emitting ([sup 95]Nb, [sup 95]Zr, [sup 103]Ru, [sup 106]Ru, [sup 137]Cs, [sup 241]Am) radionuclides in their tissues and organs. Previous studies have attempted to determine the principal nuclide source to marine organisms by comparing nuclide activity ratios in their tissues, sea water and particulate material. From the environmental samples studied here, no single transport medium appears to dominate uptake. The primary radiological implantation of the observed radionuclide concentrations in Ravenglass mussels and winkles is that, from seafood ingestion, the critical group receives only a small percentage (ca. 10%) of the ICRP-recommended subsidiary dose limit. Dose contributions from [sup 210]Po are higher than those from [sup 239] + [sup 240]Pu in mussels but are less than those from [sup 239] [sup +] [sup 240]Pu in winkles. (Author).

  15. Implications of sedimentological and hydrological processes on the distribution of radionuclides: the example of a salt marsh near Ravenglass, Cumbria

    Energy Technology Data Exchange (ETDEWEB)

    Carr, A.P.; Blackley, M.W.L.

    1986-05-01

    This paper summarizes sedimentological and hydrological studies at a salt marsh site on the north bank of the River Esk near Ravenglass which have a bearing on the fate of the low-level radioactive effluent from the reprocessing facility at Sellafield, Cumbria. A range of techniques has been used including electromagnetic distance measurement (EDM) and pore water pressure studies. The results show that: (a) Over a two-year period there were no significant net changes in salt marsh creek level, although shorter-term (probably seasonal) fluctuations, of the order of 2 cm, occurred. These were attributed to expansion of clay particles during the winter months. Nearby, however, there were vertical changes of the order of 1 m due to erosion. (b) Pore water pressures indicated a dynamic situation with very rapid responses both to tidal fluctuations and to rainfall. During neap tides there was clear evidence for water seeping upwards from the underlying clay/sand interface. Shortlived radionuclides (/sup 95/Zr//sup 95/Nb and /sup 106/Ru) were detected in this zone. (c) soil polygons, once initiated by desiccation, thereafter provide preferential routes for water (and radionuclides) to the sub-surface sediment. These, and other results, are discussed in the context of previous studies. It is concluded that the complexity of the estuarine environment results in most data being site specific.

  16. Radioactivity in food crops

    International Nuclear Information System (INIS)

    Published levels of radioactivity in food crops from 21 countries and 4 island chains of Oceania are listed. The tabulation includes more than 3000 examples of 100 different crops. Data are arranged alphabetically by food crop and geographical origin. The sampling date, nuclide measured, mean radioactivity, range of radioactivities, sample basis, number of samples analyzed, and bibliographic citation are given for each entry, when available. Analyses were reported most frequently for 137Cs, 40K, 90Sr, 226Ra, 228Ra, plutonium, uranium, total alpha, and total beta, but a few authors also reported data for 241Am, 7Be, 60Co, 55Fe, 3H, 131I, 54Mn, 95Nb, 210Pb, 210Po, 106Ru, 125Sb, 228Th, 232Th, and 95Zr. Based on the reported data it appears that radioactivity from alpha emitters in food crops is usually low, on the order of 0.1 Bq.g-1 (wet weight) or less. Reported values of beta radiation in a given crop generally appear to be several orders of magnitude greater than those of alpha emitters. The most striking aspect of the data is the great range of radioactivity reported for a given nuclide in similar food crops with different geographical origins

  17. Study of the ruthenium fission-product behavior in the containment, in the case of a nuclear reactor severe accident

    International Nuclear Information System (INIS)

    Ruthenium tetroxide is an extremely volatile and highly radio-toxic species. During a severe accident with air ingress in the reactor vessel, ruthenium oxides may reach the reactor containment building in significant quantities. Therefore, a better understanding of the RuO4(g) behaviour in the containment atmosphere is of primary importance for the assessment of radiological consequences, in the case of potential releases of this species into the environment. A RuO4(g) decomposition kinetic law was determined. Steam seems to play a catalytic role, as well as the presence of ruthenium dioxide deposits. The temperature is also a key parameter. The nature of the substrate, stainless steel or paint, did not exhibit any chemical affinities with RuO4(g). This absence of reactivity was confirmed by XPS analyses, which indicate the presence of the same species in the Ru deposits surface layer whatever the substrates considered. It has been concluded that RuO4(g) decomposition corresponds to a bulk gas phase decomposition. The ruthenium re-volatilization phenomenon under irradiation from Ru deposits was also highlighted. An oxidation kinetic law was determined. The increase of the temperature and the steam concentration promote significantly the oxidation reaction. The establishment of Ru behavioural laws allowed making a modelling of the Ru source term. The results of the reactor calculations indicate that the values obtained for 106Ru source term are closed to the reference value considered currently by the IRSN, for 900 MWe PWR safety analysis. (author)

  18. Extraction of certain radionuclides from aqueous schungite solutions

    International Nuclear Information System (INIS)

    The sorption of 90Sr, 106Ru, 137Cs, and 238Pu from aqueous solutions over a wide pH range was studied. Swelled schungite chips (Nigozero, Kondopozhsk region) (1) and schungite (Onezhsk lake) (2) were tested as sorbents. The minerals were used both untreated and after oxidation (HNO3, 1:1, contact time 1 day). The oxidation, judging from the literature, facilitates the formation of carboxylic and phenolic functional groups on the surface of the carbon-containing sorbents. The presence of such groups is responsible for the high selectivity of the sorbents for multicharged cations. Futhermore, the hydrophobicity of the schungites enormously decreases after the oxidation. The studied sorbents had an average particle size of 0.08-0.1 mm. The schungite was contacted with the solution under static conditions with periodic stirring in order to establish equilibrium. The concentration of the radionuclides was 2-4 MBq/liter. The solution volumes were 10 ml. The sorbent content was 0.01 g. The required pH was set by adding HCl or NaOH

  19. Correction factors for the ISO rod phantom, a cylinder phantom, and the ICRU sphere for reference beta radiation fields of the BSS 2

    International Nuclear Information System (INIS)

    The International Organization for Standardization (ISO) requires in its standard ISO 6980 that beta reference radiation fields for radiation protection be calibrated in terms of absorbed dose to tissue at a depth of 0.07 mm in a slab phantom (30 cm x 30 cm x 15 cm). However, many beta dosemeters are ring dosemeters and are, therefore, irradiated on a rod phantom (1.9 cm in diameter and 30 cm long), or they are eye dosemeters possibly irradiated on a cylinder phantom (20 cm in diameter and 20 cm high), or area dosemeters irradiated free in air with the conventional quantity value (true value) being defined in a sphere (30 cm in diameter, made of ICRU tissue (International Commission on Radiation Units and Measurements)). Therefore, the correction factors for the conventional quantity value in the rod, the cylinder, and the sphere instead of the slab (all made of ICRU tissue) were calculated for the radiation fields of 147Pm, 85Kr, 90Sr/90Y, and, 106Ru/106Rh sources of the beta secondary standard BSS 2 developed at PTB. All correction factors were calculated for 0° up to 75° (in steps of 15°) radiation incidence. The results are ready for implementation in ISO 6980-3 and have recently been (partly) implemented in the software of the BSS 2

  20. Thermal stability of the C106 dye in robust electrolytes

    DEFF Research Database (Denmark)

    Lund, Torben; Phuong, Nguyen Tuyet; Pechy, Peter;

    degradation was the only loss mechanism in a DSC during thermal treatment the reduction in the DSC efficiency after long term thermal treatment may be estimated to 12%[3]. The dye stability therefore does not seem to be the limiting factor in full filling the requirements of the IEC 1215 standard thermal......Thermal stability of the C106 dye in robust electrolytes. We have investigated the thermal stability and degradation chemistry of the ruthenium dye C106 (Figure 1) at 80 ◦C in the “robust” electrolyte “B” comprised of 1.0 M DMII, 0.03 M I2, 0.5 M NBB, and 0.1 M GuNCS in 3-methoxypropionitrile (3......-MPN) introduced by Gao et al. in 2008. [1]. Figure 1 Thermal degradation of C106 bound to TiO2 at 80 ºC in dark as a function of heating time. ● C106 = RuLL´(NCS)2 ■ RuLL´(NCS)(NBB)+ ▲ RuLL´(NCS)(3-MPN)+ The C106 dye was attached to the surface of TiO2 nano-particles and stable colloidal solutions...

  1. Assessment of Cesium, Iodine, Strontium and Ruthenium isotopes behaviour in urban areas, after contamination from accidental release

    International Nuclear Information System (INIS)

    The exposures of urban populations to the radiation derived from the deposition, after accidental atmospheric releases, of 137 Cs, 134 Cs, 129 I, 131 I, 133 I, 89 Sr, 103 Ru and 106 Ru were assessed, using the integrated system for the evaluation of environmental radiological impact in emergency situations, developed by the Instituto de Radioprotecao e Dosimetria (IRD)/Comissao Nacional de Energia Nuclear (CNEN). These radionuclide are fission products likely to be emitted in the occurrence of severe nuclear reactor accidents. Their environmental behaviour in urban areas, due to their deposition in soil, in urban surfaces and in vegetable-garden food products, such as leafy and non-leafy vegetables, were analyzed, and dose assessments at the short, medium and long terms were performed, with an without the application of protective measures for reduction of doses. Simulations of unitary initial deposition for each radionuclide and of two different potential accidents involving water reactors (PWR), with different source terms and distinct deposition for each radionuclide, were performed. Results were analyzed on the basis of relative relevance of radionuclides and pathways for the exposure of members of the public, as a function of age and time after the release. It was also performed an assessment of the effectiveness of protective measures as a function of the moment of their implementation. (author)

  2. Electrochemical treatment of liquid wastes

    Energy Technology Data Exchange (ETDEWEB)

    Hobbs, D.T. [Savannah River Technology Center, Aiken, SC (United States)

    1997-10-01

    Under this task, electrochemical treatment processes are being evaluated and developed for the destruction of organic compounds and nitrates/nitrites and the removal of other hazardous species from liquid wastes stored throughout the DOE complex. This technology targets the (1) destruction of nitrates, nitrites and organic compounds; (2) removal of radionuclides; and (3) removal of RCRA metals. The development program consists of five major tasks: (1) evaluation of electrochemical reactors for the destruction and removal of hazardous waste components, (2) development and validation of engineering process models, (3) radioactive laboratory-scale tests, (4) demonstration of the technology in an engineering-scale reactor, and (5) analysis and evaluation of test data. The development program team is comprised of individuals from national laboratories, academic institutions, and private industry. Possible benefits of this technology include: (1) improved radionuclide separation as a result of the removal of organic complexants, (2) reduction in the concentrations of hazardous and radioactive species in the waste (e.g., removal of nitrate, mercury, chromium, cadmium, {sup 99}Tc, and {sup 106}Ru), (3) reduction in the size of the off-gas handling equipment for the vitrification of low-level waste (LLW) by reducing the source of NO{sub x} emissions, (4) recovery of chemicals of value (e.g. sodium hydroxide), and (5) reduction in the volume of waste requiring disposal.

  3. Response of ionization chamber based pocket dosimeter to beta radiation.

    Science.gov (United States)

    Kumar, Munish; Gupta, Anil; Pradhan, S M; Bakshi, A K; Chougaonkar, M P; Babu, D A R

    2013-12-01

    Quantitative estimate of the response of ionization chamber based pocket dosimeters (DRDs) to various beta sources was performed. It has been established that the ionization chamber based pocket dosimeters do not respond to beta particles having energy (Emax)1 MeV, the DRDs exhibit measureable response and the values are ~8%, ~14% and ~27% per mSv for natural uranium, (90)Sr/(90)Y and (106)Ru/(106)Rh beta sources respectively. As the energy of the beta particles increases, the response also increases. The response of DRDs to beta particles having energy>1 MeV arises due to the fact that the thickness of the chamber walls is less than the maximum range of beta particles. This may also be one of the reasons for disparity between doses measured with passive/legal dosimeters (TLDs) and DRDs in those situations in which radiation workers are exposed to mixed field of gamma photons and beta particles especially at uranium processing plants, nuclear (power and research) reactors, waste management facilities and fuel reprocessing plants etc. The paper provides the reason (technical) for disparity between the doses recorded by TLDs and DRDs in mixed field of photons and beta particles.

  4. Air radioactivity levels following the Fukushima reactor accident measured at the Laboratoire Souterrain de Modane, France.

    Science.gov (United States)

    Loaiza, P; Brudanin, V; Piquemal, F; Reyss, J-L; Stekl, I; Warot, G; Zampaolo, M

    2012-12-01

    The radioactivity levels in the air of the radionuclides released by the Fukushima accident were measured at the Laboratoire Souterrain de Modane, in the South-East of France, during the period 25 March-18 April 2011. Air-filters from the ventilation system exposed for one or two days were measured using low-background gamma-ray spectrometry. In this paper we present the activity concentrations obtained for the radionuclides (131)I, (132)Te, (134)Cs, (137)Cs, (95)Nb, (95)Zr, (106)Ru, (140)Ba/La and (103)Ru. The activity concentration of (131)I was of the order of 100 μBq/m(3), more than 100 times higher than the activities of other fission products. The highest activities of (131)I were measured as a first peak on 30 March and a second peak on 3-4 April. The activity concentrations of (134)Cs and (137)Cs varied from 5 to 30 μBq/m(3). The highest activity concentration recorded for Cs corresponded to the same period as for (131)I, with a peak on 2-3 April. The results of the radioactivity concentration levels in grass and mushrooms exposed to the air in the Modane region were also measured. Activity concentrations of (131)I of about 100 mBq/m(2) were found in grass.

  5. Assessment of the potential for radionuclide migration from a nuclear-explosion cavity

    International Nuclear Information System (INIS)

    The source term for radionuclides in the region of the Cambric nuclear explosion has been determined. Drillback cores were obtained and analyzed, and water was pumped from several vertical zones and analyzed. Most of the radioactivity produced in the test was found to be retained in the fused debris with only low concentrations in the water which had been in contact with the debris for nearly ten years. Most of the radioactivity and the highest specific activities of all radionuclides were found to be in the region of the original explosion cavity. No activity was found 50 m below the cavity. Water from the region of highest radioactivity at the bottom of the cavity contained only tritium and 90Sr at levels higher than the recommended concentration guides for drinking water in uncontrolled areas. During nearly six years of pumping from a satellite well located 91 m from the Cambric cavity, only tritium 85Kr have been positively identified in water removed from this well, although there is some evidence for the possible migration of minute amounts of 106Ru. These results are consistent with laboratory studies which indicate that, in general, radionuclide sorption is sufficiently high to preclude the migration of such nuclides from the original cavity to the satellite well in the near future

  6. Field and model investigations of external gamma dose rates along the Cumbrian coast, NW England.

    Science.gov (United States)

    McDonald, P; Bryan, S E; Hunt, G J; Baldwin, M; Parker, T G

    2005-03-01

    A survey of the contribution to external dose from gamma rays originating from intertidal sediments in the vicinity of the British Nuclear Group Sellafield site showed that the major anthropogenic contributions were due to (137)Cs and (60)Co. At some sites, traces of other anthropogenic radionuclides were detected, namely (106)Ru, (125)Sb, and (154)Eu. The proportions of fine grained material (Drigg Barn Scar and Whitehaven Coal Sands sites, which had their own unique characteristics. The highest (60)Co activity concentrations in this study were detected at Drigg Barn Scar. These relatively high activity concentrations of (60)Co were due to the presence of (60)Co in mussels and barnacles, hence upsetting the fine sediment relationships used in previous dose calculations. Whitehaven Coal Sands was unusual in that it contained higher levels of radionuclides than would be expected in sandy sediment. The mineralogy of these sediments was the controlling factor on (137)Cs binding, rather than the proportion of fine grained material. By adjusting the effective fine grained sediment proportions for calculations involving (60)Co and (137)Cs at Drigg Barn Scar and Whitehaven Coal Sands respectively, the CUMBRIA77/DOSE77 model predictions could be improved upon significantly for these sites. This work highlights the influence of particle size and sediment composition on external dose rate calculations, as well as the potential for external dose contributions from biota. PMID:15798279

  7. Field and model investigations of external gamma dose rates along the Cumbrian coast, NW England

    International Nuclear Information System (INIS)

    A survey of the contribution to external dose from gamma rays originating from intertidal sediments in the vicinity of the British Nuclear Group Sellafield site showed that the major anthropogenic contributions were due to 137Cs and 60Co. At some sites, traces of other anthropogenic radionuclides were detected, namely 106Ru, 125Sb, and 154Eu. The proportions of fine grained material (60Co activity concentrations in this study were detected at Drigg Barn Scar. These relatively high activity concentrations of 60Co were due to the presence of 60Co in mussels and barnacles, hence upsetting the fine sediment relationships used in previous dose calculations. Whitehaven Coal Sands was unusual in that it contained higher levels of radionuclides than would be expected in sandy sediment. The mineralogy of these sediments was the controlling factor on 137Cs binding, rather than the proportion of fine grained material. By adjusting the effective fine grained sediment proportions for calculations involving 60Co and 137Cs at Drigg Barn Scar and Whitehaven Coal Sands respectively, the CUMBRIA77/DOSE77 model predictions could be improved upon significantly for these sites. This work highlights the influence of particle size and sediment composition on external dose rate calculations, as well as the potential for external dose contributions from biota

  8. Study of charge collection and noise in non-irradiated and irradiated silicon detectors

    CERN Document Server

    Leroy, C; Dezillie, B; Glaser, M; Lemeilleur, F; Trigger, I

    1996-01-01

    The large collection and noise were studied in non-irradiated and irradiated silicon detectors as a function of temperature (T), shaping time (0) and fluence , up to about 1,2 x 10(14) protons per cm2 for minimum-ionizing electrons yielded by a 106 Ru source. The noise of irradiated detectors is found to be dominted for short shaping times (¾50ns) by a series noise compo- nent, while for longer shaping times („80ns) a parallel noise component (correlated with the reverse current) prevails. For non-irradiated detectors, where the reverse current is three orders of magnetude smaller compared with irradiated detectors, the series noises dominates over the whole range of shaping times investigated (20-150ns). A signal degradation is observed for irradiated detectors. However, the signal ca be distinguished from noise, even after a fluence of about 1.2 x10(14) protons per cm2, at a temperature of 6øC and with a shaping time tipical of rge LHC inter-bunch crossing time (20-30ns). The measurements of the signal a...

  9. Study of charge collection and noise in non-irradiated and irradiated silicon detectors

    Energy Technology Data Exchange (ETDEWEB)

    Leroy, C. [Montreal Univ., PQ (Canada); Bates, S. [CERN, ECP, CH-1211 Geneva (Switzerland); Dezillie, B. [CERN, ECP, CH-1211 Geneva (Switzerland); Glaser, M. [CERN, ECP, CH-1211 Geneva (Switzerland); Lemeilleur, F. [CERN, ECP, CH-1211 Geneva (Switzerland); Trigger, I. [Montreal Univ., PQ (Canada)

    1997-04-01

    Charge collection and noise were studied in non-irradiated and irradiated silicon detectors as a function of temperature (T), shaping time ({theta}) and fluence ({Phi}), up to about 1.2 x 10{sup 14} protons cm{sup -2}, for minimum ionizing electrons yielded by a {sup 106}Ru source. The noise of irradiated detectors is found dominated for short shaping times ({theta}{<=}50 ns) by a series noise component while for longer shaping time ({theta}{>=}80 ns) a parallel noise component (correlated with the reverse current) prevails. For non-irradiated detectors, where the reverse current is three orders of magnitude smaller compared with irradiated detectors, the series noise dominates over the whole range of shaping times investigated (20-150 ns). A signal degradation is observed for irradiated detectors. However, the signal can be distinguished from noise, even after a fluence of about 1.2 x 10{sup 14} protons cm{sup -2}, at a temperature of 6 C and with a shaping time typical of LHC inter-bunch crossing time (20-30 ns). The measurement of the signal as a function of voltage shows that irradiated detectors depleted at 50% of the full depletion voltage can still provide a measurable signal-to-noise ratio. (orig.).

  10. Development of a method for analyzing traces of ruthenium in plant materials and determination of the transfer factors soil/plant for ruthenium compounds from reprocessing plants

    International Nuclear Information System (INIS)

    In an artificial humous and sandy soil spiked with 106Ru as RuO2 and RuCl3, pasture grass was grown under artificial illumination in our laboratory. The amounts of ruthenium taken up by the plants were determined by γ-spectrometry. For open-air investigations with pasture grass, wheat and potatoes inactive ruthenium(III) chloride and ruthenium nitrosylchloride were used. Ruthenium was determined by electrothermal atomic absorption spectrometry (ETAAS) after destroying the organic material and concentrating the solution. The concentration and chemical form of the ruthenium exert an unimportant influence on the transfer factor. For the pasture-grass, the stems of wheat and the weed of potatoes it amounts to 0.00005 to 0.0015, for the ear of wheat to about 0.00005. In peeled potatoes there was no ruthenium detectable, therefore the limit of detection leads to a transfer factor ≤ 0.00001. So it is evident that ruthenium is little available for the roots of the plants. In the event of an accident in a nuclear plant the uptake of radioactive ruthenium by roots has only negligible radioecological consequences. This applies even if 50 years of ruthenium enrichment in the soil are assumed. (orig./RB)

  11. Radiation Protection in Brachytherapy. Report of the SEFM Task Group on Brachytherapy; Proteccion radiologica en Braquiterapia. Informe del grupo de trabajo de Braquiterapia de la SEFM

    Energy Technology Data Exchange (ETDEWEB)

    Perez-Calatayud, J.; Corredoira Silva, E.; Crispin Contreras, V.; Eudaldo Puell, T.; Frutos Baraja, J. de; Pino Sorroche, F.; Pujades Claumarchirant, M. C.; Richart Sancho, J.

    2015-07-01

    This document presents the report of the Brachytherapy Task Group of the Spanish Society of Medical Physics. It is dedicated to the radiation protection aspects involved in brachytherapy. The aim of this work is to include the more relevant aspects related to radiation protection issues that appear in clinical practice, and for the current equipment in Spain. Basically this report focuses on the typical contents associated with high dose rate brachytherapy with {sup 1}92Ir and {sup 6}0Co sources, and permanent seed implants with {sup 1}25I, {sup 1}03Pd and {sup 1}31Cs, which are the most current and widespread modalities. Ophthalmic brachytherapy (COMS with {sup 1}25I, {sup 1}06Ru, {sup 9}0Sr) is also included due to its availability in a significant number of spanish hospitals. The purpose of this report is to assist to the medical physicist community in establishing a radiation protection program for brachytherapy procedures, trying to solve some ambiguities in the application of legal requirements and recommendations in clinical practice. (Author)

  12. Electrochemical treatment of liquid wastes

    International Nuclear Information System (INIS)

    Under this task, electrochemical treatment processes are being evaluated and developed for the destruction of organic compounds and nitrates/nitrites and the removal of other hazardous species from liquid wastes stored throughout the DOE complex. This technology targets the (1) destruction of nitrates, nitrites and organic compounds; (2) removal of radionuclides; and (3) removal of RCRA metals. The development program consists of five major tasks: (1) evaluation of electrochemical reactors for the destruction and removal of hazardous waste components, (2) development and validation of engineering process models, (3) radioactive laboratory-scale tests, (4) demonstration of the technology in an engineering-scale reactor, and (5) analysis and evaluation of test data. The development program team is comprised of individuals from national laboratories, academic institutions, and private industry. Possible benefits of this technology include: (1) improved radionuclide separation as a result of the removal of organic complexants, (2) reduction in the concentrations of hazardous and radioactive species in the waste (e.g., removal of nitrate, mercury, chromium, cadmium, 99Tc, and 106Ru), (3) reduction in the size of the off-gas handling equipment for the vitrification of low-level waste (LLW) by reducing the source of NOx emissions, (4) recovery of chemicals of value (e.g. sodium hydroxide), and (5) reduction in the volume of waste requiring disposal

  13. The Cambric migration experiment: A summary report

    International Nuclear Information System (INIS)

    The Cambric migration experiment was undertaken in 1974 to provide data concerning the migration of radionuclides away from the site of a nuclear test where there is an induced hydraulic gradient. First, the distribution of radioactive isotopes around the site of the Cambric explosion was investigated by analysis of samples recovered from a hole drilled through the nuclear debris. Then water was pumped from a well, located 91 m away, to induce flow from the nuclear explosion site. Analyses of water samples showed that the migration velocity of tritium, 16Cl, 85Kr, 99Tc, 106Ru, and 129I was nearly the same as that of the moving water, from the explosion site to the pumped well. Less than 0.5% of the total 90Sr and 0.0003% of the total 137Cs accompanied the tritium to the pumped well, although both isotopes appear to have migrated away from the source zone to some extent. The concentration of 239Pu at the pumped well was below the detection limit of 106 atoms/m ell in water collected at the time of peak tritium concentration. Peak tritium concentration in the pumped water occurred when 5,000,000 m3 had been pumped

  14. A study of gamma-emitting radionuclides present into the sediments and algae of the ''Baie de l'Orne'' (Central Normandy Coast) collecting during the years 1980 - 1982

    International Nuclear Information System (INIS)

    The present status of some environmental effects of existing sources of gamma-emitting radionuclides, along the Central part of the Normandy Coast (Calvados shores and river Orne mouth) was determined. A systematic study was made on the behaviour of the marine sediments and brown alga 'Laminaria digitata' with regard to their properties as indicators of radioactive contamination. Marine sediments were collected into the river Orne at fixed locations and into the sea in and around the estuary from 1977 to 1982. Algae samples were picked up along the coast from 1980 to 1982, mostly on the western part of the Orne estuary. Dosimetry techniques employed have produced accurate and reliable results, despite the very low levels of activity involved. Gamma-emitting radionuclides present in the environment (chiefly 106Ru, 137Cs, 95Zr) were identified and measured. Their behaviour into the marine sediments and into Laminaria Digitata were determined. This study provides evidence on the presence of numerous gamma-emitting radionuclides into the marine environment of the Central part of the Normandy coast, but, altogether with very low levels of radioactivity

  15. Radioactivity in food crops

    Energy Technology Data Exchange (ETDEWEB)

    Drury, J.S.; Baldauf, M.F.; Daniel, E.W.; Fore, C.S.; Uziel, M.S.

    1983-05-01

    Published levels of radioactivity in food crops from 21 countries and 4 island chains of Oceania are listed. The tabulation includes more than 3000 examples of 100 different crops. Data are arranged alphabetically by food crop and geographical origin. The sampling date, nuclide measured, mean radioactivity, range of radioactivities, sample basis, number of samples analyzed, and bibliographic citation are given for each entry, when available. Analyses were reported most frequently for /sup 137/Cs, /sup 40/K, /sup 90/Sr, /sup 226/Ra, /sup 228/Ra, plutonium, uranium, total alpha, and total beta, but a few authors also reported data for /sup 241/Am, /sup 7/Be, /sup 60/Co, /sup 55/Fe, /sup 3/H, /sup 131/I, /sup 54/Mn, /sup 95/Nb, /sup 210/Pb, /sup 210/Po, /sup 106/Ru, /sup 125/Sb, /sup 228/Th, /sup 232/Th, and /sup 95/Zr. Based on the reported data it appears that radioactivity from alpha emitters in food crops is usually low, on the order of 0.1 Bq.g/sup -1/ (wet weight) or less. Reported values of beta radiation in a given crop generally appear to be several orders of magnitude greater than those of alpha emitters. The most striking aspect of the data is the great range of radioactivity reported for a given nuclide in similar food crops with different geographical origins.

  16. Ac, La, and Ce radioimpurities in {sup 225}Ac produced in 40-200 MeV proton irradiations of thorium

    Energy Technology Data Exchange (ETDEWEB)

    Engle, Jonathan W.; Ballard, Beau D. [Los Alamos National Laboratory, NM (United States); Weidner, John W. [Air Force Institute of Technology, Wright Patterson Air Force Base, OH (United States); and others

    2014-10-01

    Accelerator production of {sup 225}Ac addresses the global supply deficiency currently inhibiting clinical trials from establishing {sup 225}Ac's therapeutic utility, provided that the accelerator product is of sufficient radionuclidic purity for patient use. Two proton activation experiments utilizing the stacked foil technique between 40 and 200 MeV were employed to study the likely co-formation of radionuclides expected to be especially challenging to separate from {sup 225}Ac. Foils were assayed by nondestructive γ-spectroscopy and by α-spectroscopy of chemically processed target material. Nuclear formation cross sections for the radionuclides {sup 226}Ac and {sup 227}Ac as well as lower lanthanide radioisotopes {sup 139}Ce, {sup 141}Ce, {sup 143}Ce, and {sup 140}La whose elemental ionic radii closely match that of actinium were measured and are reported. The predictions of the latest MCNP6 event generators are compared with measured data, as they permit estimation of the formation rates of other radionuclides whose decay emissions are not clearly discerned in the complex spectra collected from {sup 232}Th(p,x) fission product mixtures. (orig.)

  17. Activation cross-section measurement of deuteron induced reactions on cerium for biomedical applications and for development of reaction theory

    Energy Technology Data Exchange (ETDEWEB)

    Tárkányi, F.; Takács, S. [Institute for Nuclear Research, Hungarian Academy of Sciences (ATOMKI), 4026 Debrecen (Hungary); Ditrói, F., E-mail: ditroi@atomki.hu [Institute for Nuclear Research, Hungarian Academy of Sciences (ATOMKI), 4026 Debrecen (Hungary); Csikai, J. [Institute for Nuclear Research, Hungarian Academy of Sciences (ATOMKI), 4026 Debrecen (Hungary); Hermanne, A. [Cyclotron Laboratory, Vrije Universiteit Brussel (VUB), Laarbeeklaan 103, 1090 Brussels (Belgium); Ignatyuk, A.V. [Institute of Physics and Power Engineering (IPPE), Obninsk 249020 (Russian Federation)

    2013-12-01

    Highlights: • Excitation function measurement of deuteron induced reactions on natural Ce up to 50 MeV. • Model code calculations with EMPIRE-D, ALICE-D and TALYS (TENDL-2012). • Integral production yield calculation. • Discussion of medically relevant radioisotopes {sup 143}Pr, {sup 142}Pr, {sup 141}Ce and {sup 139}Ce. -- Abstract: In the frame of a systematic study of deuteron induced nuclear reactions on lanthanides we have measured the excitation functions on natural cerium for production of {sup 142,139,138m,137}Pr, {sup 143,141,139,137m,137,135}Ce and {sup 140}La up to 50 MeV deuteron energy using the activation method with stacked-foil irradiation technique and high-resolution γ-ray spectrometry. The cross-sections of the investigated reactions were calculated using the modified pre-compound model codes ALICE-IPPE-D and EMPIRE-II-D. A comparison was made also with the data retrieved from the TENDL-2012 library, based on the latest version of the TALYS code system. The measured cross-section data are important for further improvement of nuclear reaction models and for practical applications in nuclear medicine and other labeling and activation studies.

  18. The full structure of the KLL Auger spectrum of La observed in the radioactive decay of {sup 139}Ce in a solid matrix

    Energy Technology Data Exchange (ETDEWEB)

    Inoyatov, A.Kh., E-mail: inoyatov@nusun.jinr.ru [Laboratory of Nuclear Problems, JINR, Dubna, Moscow Region (Russian Federation); Institute of Applied Physics, National University, Tashkent (Uzbekistan); Perevoshchikov, L.L. [Laboratory of Nuclear Problems, JINR, Dubna, Moscow Region (Russian Federation); Kovalík, A. [Laboratory of Nuclear Problems, JINR, Dubna, Moscow Region (Russian Federation); Nuclear Physics Institute of the ASCR, Řež near Prague (Czech Republic); Filosofov, D.V. [Laboratory of Nuclear Problems, JINR, Dubna, Moscow Region (Russian Federation); Zhdanov, V.S. [Institute of Nuclear Physics, Almaty (Kazakhstan); Lubashevskiy, A.V. [Laboratory of Nuclear Problems, JINR, Dubna, Moscow Region (Russian Federation); Hons, Z. [Nuclear Physics Institute of the ASCR, Řež near Prague (Czech Republic)

    2013-04-15

    Highlights: •The KLL Auger spectrum of Ce measured for the first time in detail. •Energies and relative intensities of the all nine basic spectrum components determined. •An influence of the “atomic structure effect” on the absolute KLL energies indicated. •A perceptible influence of the relativistic effects on the KLL spectrum found. -- Abstract: For the first time, the KLL Auger spectrum of La (Z = 57) following the electron capture decay of radioactive {sup 139,141}Ce in a solid source was measured. The all nine basic spectrum components were resolved and their energies and relative intensities were determined and compared with theoretical expectations. The absolute energy of 27 383.8 ± 2.2 eV derived for the dominant KL{sub 2}L{sub 3}({sup 1}D{sub 2}) transition was found to be higher by 7.7 ± 2.2 eV (i.e. more than 3σ) than a value predicted by the widely used relativistic semi-empirical calculations by Larkins. The possible reasons for this discrepancy are discussed. Despite of less accuracy of some measured data, the predicted strong influence of the relativistic effects on the KL{sub 1}L{sub 2}({sup 3}P{sub 0}) transition intensity was nevertheless proved.

  19. Inorganic oxides as alternative in the separation of non fissioned residual uranium

    International Nuclear Information System (INIS)

    The Al2O3, SiO2 and SnO2 as well as vegetable carbon have been studied for its possible use as sorbent in the concentration and separation of non fissioned residual uranium of some fission products such as: 141 Ce, 134 Cs, 125 Sb, 103 Ru, 95 Zr, 95 Nb of alkaline aqueous systems. The separation efficiency has been evaluated using natural uranium and radionuclides in static and dynamic processes, through liquid scintillation and gamma spectrometry. Therefore Al2O3, SiO2, SnO2 and carbon were pre-treated thermic and chemically and characterized through the technique of Nitrogen absorption analysis, X-ray diffraction and IR spectroscopy. By means of the p H determination and the aqueous system potential the present hydrolysis products were determined. The inorganic oxides show structural and surface changes due to the treatment. The adsorption process is realized by different mechanism depending of the sorbent. The results show that the retention capacity is a dependence of the oxides pre-treatment and of the hydrolysis products in the aqueous system, as well as of the experimental conditions. Not in this way for carbon in which the results show the treatment and the experimental conditions significantly have not influence in its adsorption capacity. (Author)

  20. Inorganic oxides as alternative in the separation of non fissioned residual uranium; Oxidos inorganicos como alternativa en la separacion del uranio residual no fisionado

    Energy Technology Data Exchange (ETDEWEB)

    Baca G, A

    1997-07-01

    The Al{sub 2}O{sub 3}, SiO{sub 2} and SnO{sub 2} as well as vegetable carbon have been studied for its possible use as sorbent in the concentration and separation of non fissioned residual uranium of some fission products such as: {sup 141} Ce, {sup 134} Cs, {sup 125} Sb, {sup 103} Ru, {sup 95} Zr, {sup 95} Nb of alkaline aqueous systems. The separation efficiency has been evaluated using natural uranium and radionuclides in static and dynamic processes, through liquid scintillation and gamma spectrometry. Therefore Al{sub 2}O{sub 3}, SiO{sub 2}, SnO{sub 2} and carbon were pre-treated thermic and chemically and characterized through the technique of Nitrogen absorption analysis, X-ray diffraction and IR spectroscopy. By means of the p H determination and the aqueous system potential the present hydrolysis products were determined. The inorganic oxides show structural and surface changes due to the treatment. The adsorption process is realized by different mechanism depending of the sorbent. The results show that the retention capacity is a dependence of the oxides pre-treatment and of the hydrolysis products in the aqueous system, as well as of the experimental conditions. Not in this way for carbon in which the results show the treatment and the experimental conditions significantly have not influence in its adsorption capacity. (Author)

  1. Blood flow in transplantable bladder tumors treated with hematoporphyrin derivative and light

    Energy Technology Data Exchange (ETDEWEB)

    Selman, S.H.; Kreimer-Birnbaum, M.; Klaunig, J.E.; Goldblatt, P.J.; Keck, R.W.; Britton, S.L.

    1984-05-01

    Following hematoporphyrin derivative (HPD) photochemotherapy, blood flow to transplantable N-(4-(5-nitro-2-furyl)-2-thia-zolyl) formamide-induced urothelial tumors was determined by a radioactive microsphere technique using either /sup 103/Ru or /sup 141/Ce. Two tumors were implanted s.c. on the abdominal wall of Fischer 344 weanling rats. HPD (10 mg/kg body weight) was administered 24 hr prior to phototherapy (red light, greater than 590 nm; 360 J/sq cm). One of the two tumors was shielded from light exposure and served as an internal control. Blood flows were determined in control animals that received no treatment (Group 1), HPD only (Group 2), or light only (Group 3). In Groups 4 and 5, animals received the combination of HPD and light but differed in the time interval between treatment and blood flow determinations (10 min and 24 hr, respectively). Only blood flow to tumors treated with HPD and light showed a significant decrease (p less than 0.05) when compared with their internal controls both at 10 min (Group 4) and 24 hr (Group 5) after completion of phototherapy. These studies suggest that disruption of tumor blood flow may be an important mechanism of action of this method of cancer therapy.

  2. Transfer of radionuclides from maternal food to the fetus and nursing infants of minipigs

    Energy Technology Data Exchange (ETDEWEB)

    Timmermans, R.; Van Hees, M.; Vandecasteele, C.H.; Vankerkom, J.; Gerber, G.B. (Centre d' Etude de l' Energie Nucleaire, Mol (Belgium))

    1992-01-01

    Transfer of {sup 110m}Ag, {sup 58}Co, {sup 59}Fe, {sup 141}Ce, {sup 103}Ru, {sup 88}Y, {sup 85}Sr, {sup 51}Mn, {sup 134}Cs, {sup 152}Eu, {sup 95m}Tc, {sup 75}Se, {sup 65}Zn and {sup 133}Gd was investigated in utero and during lactation in minipigs given the radioactive material added to food from day 50 of pregnancy until the end of lactation. The paper presents selected results on Ag, Co, Fe, Sr, Mn, Cs, Ru and Y and Tc. Transfer was highest for Cs and, in haemopoietic tissues, for Fe. Lower transfer was found for Ag, Fe, Mn with some preference for certain tissues (Ag in brain and liver, Mn in pancreas). Sr accumulated almost exclusively in bone and Tc in thyroid with higher concentrations in fetal and infant tissues than in maternal tissues. Lanthanides, Ru and Y were all close to detection limits or below in most maternal or fetal or infant tissues and could be found in bone and, less consistently, in kidney and liver. (author).

  3. Determination of uranium fission products interference factors in neutron activation analysis; Determinacao de fatores de interferencia de produtos de fissao de uranio na analise por ativacao neutronica

    Energy Technology Data Exchange (ETDEWEB)

    Ribeiro Junior, Ibere Souza

    2014-09-01

    Neutron activation analysis is a method used in the determination of several elements in different kinds of matrices. However, when the sample contains high U levels the problem of {sup 235}U fission interference occurs. A way to solve this problem is to perform the correction using the interference factor due to U fission for the radionuclides used on elemental analysis. In this study was determined the interference factor due to U fission for the radioisotopes {sup 141}Ce, {sup 143}Ce, {sup 140}La, {sup 99}Mo, {sup 147}Nd, {sup 153}Sm and {sup 95}Zr in the research nuclear reactor IEA-R1 on IPEN-CNEN/SP. These interference factors were determined experimentally, by irradiation of synthetic standards for 8 hours in a selected position in the reactor, and theoretically, determining the epithermal to neutron fluxes ratio in the same position where synthetic standards were irradiated and using reported nuclear parameters on the literature. The obtained interference factors were compared with values reported by other works. To evaluate the reliability of these factors they were applied in the analysis of studied elements in the certified reference materials NIST 8704 Buffalo River Sediment, IRMM BCR- 667 Estuarine Sediment e IAEA-SL-1 Lake Sediment. (author)

  4. Influence of gamma irradiation on conductivity of YBa2Cu3O7

    Science.gov (United States)

    Manjunatha, H. C.

    2015-08-01

    We report a study on influence of gamma irradiation on conductivity of YBa2Cu3O7. We have measured the mass attenuation coefficient, effective atomic number, electron density and electrical conductivity for various gamma sources of energy ranging from 0.084 MeV to 1.330 MeV (170Tm, 57Co, 141Ce, 203Hg, 51Cr, 113Sn, 22Na, 137Cs, 60Co, 22Na and 60Co). The measured values agree with the theoretical values. The values of these parameters have been found to change with energy and interaction of gamma. We find evidence for a variation of the electrical conductivity of YBa2Cu3O7 with the irradiated photon energy and this variation is shown in figures up to 105 MeV. The variations of effective atomic number and electron density with energy are shown graphically for all photon interactions. Conductivity found to vary with the energy of the irradiated gamma radiation and interaction process of gamma. This kind of studies is important in the field of superconductivity.

  5. Feasibility of the instrumental neutron activation analysis of entire archaeological pottery. Part 1: Precision of the results and radiological safety of the process

    International Nuclear Information System (INIS)

    The feasibility of the instrumental neutron activation analysis of entire pieces of archaeological pottery, using low thermal neutron fluxes, is examined. The study takes into account the chemical elements relevant for archaeological investigations, as well as the degree of accuracy required for such kind of research. It is shown that after irradiation of a typical pottery sample of about 1 kg during 45 minutes, at a thermal flux of about 109 n.cm-2.s-1, analytical signals are obtained, by gamma spectrometry, with counting statistics better than 1%, for 76As, 131Ba, 141Ce, 60Co, 134Cs, 181Hf, 140La, 24Na, 122Sb, 46Sc, 153Sm and 233Pa, whereas 51Cr, 152Eu, 42K, 86Rb, 175Yb and 65Zn can be detected with counting statistics within 1% and 2%. On the other hand, the statistics of measurement are relatively poor (orders of 3% - 10%) for 177Lu, 147Nd, 239Np, 160Tb and 181Ta. The feasibility of accomplishment reliable quantitative determinations, taking into account the complexity of the analysis of entire pieces of archaeological pottery is discussed, which involves factors such as high masses, as well as asymmetric and variable shapes. (orig.)

  6. A seasonal comparison of deposition velocities and retention half-times for Cs-134 and Ce-141 on cool desert vegetation

    International Nuclear Information System (INIS)

    Due to a scarcity of reliable deposition velocity estimates for radionuclides (particularly those in the submicron range) pooled estimates have been used to predict population doses resulting from atmospheric releases of radioactive particulates. The use of these estimates has led to large uncertainties in whole body dose estimates. Deposition velocities and retention half-times were therefore determined for submicron aerosols of 141Ce (biologically inactive) and 134Cs (biologically active) on sagebrush dominated desert vegetation in SE Idaho. Approximately 250 mCi (9.3 GBq) of each radionuclide were released over stands of Artemisia tridentata (big sagebrush) and bottlebrush grass (Sitanion hystrix) during three stages of plant development - spring vegetative growth, seed development, and plant dormancy. Air filters and vegetation samples were collected immediately following each release for use in deposition velocity calculations. Vegetation sampling was continued for a period of three months to obtain retention data. Deposition velocity values were 0.20 cm/s for sagebrush and 0.025 cm/s for grass. The loss of activity on the vegetation seemed to best fit a two component exponential loss function. Short component half-times were 1 to 2 days for both species. Long component half-times were two to three weeks for the shrub species and one to two weeks for the grass species. No significant difference was observed between nuclides. (author)

  7. A probable radiation-induced epidermal carcinoma in a sheep

    International Nuclear Information System (INIS)

    The sheep discussed in this report was one of 12 wether lambs given daily doses of 144Ce-144Pr to investigate the effect of radionuclides on the alimentary tract. The sheep received 20 mCi daily over a 16 day period when treatment was discontinued due to the development of sever diarrhea and later anorexia. Changes in the sheep reported (alopecia, ulceration, disappearance of adnexa, and fibrous replacement of the dermal collagen) indicate a radiation dose in excess of that used in previous experiments. About 4.5 yr after dosing, a firm enlargement was noticed in the right ventrolateral coccygeal region. As the enlargement increased in size, ulceration and bacterial infection occurred. The sheep was killed 59 months after initial treatment and a necropsy performed. The findings were consistent with the diagnosis of locally invasive squamouscell carcinoma. The authors feel that the relative rarity of epidermal carcinomas in sheep, exposure of the coccygeal area to large doses of irradiation, and the carcinogenic effect of radiation indicates a probable cause-and-effect relationship of radiation and tumour development. (U.K.)

  8. Animal metabolism

    International Nuclear Information System (INIS)

    Studies on placental transport included the following: clearance of tritiated water as a baseline measurement for transport of materials across perfused placentas; transport of organic and inorganic mercury across the perfused placenta of the guinea pig in late gestation; and transport of cadmium across the perfused placenta of the guinea pig in late gestation. Studies on cadmium absorption and metabolism included the following: intestinal absorption and retention of cadmium in neonatal rats; uptake and distribution of an oral dose of cadmium in postweanling male and female, iron-deficient and normal rats; postnatal viability and growth in rat pups after oral cadmium administration during gestation; and the effect of calcium and phosphorus on the absorption and toxicity of cadmium. Studies on gastrointestinal absorption and mineral metabolism included: uptake and distribution of orally administered plutonium complex compounds in male mice; gastrointestinal absorption of 144Ce in the newborn mouse, rat, and pig; and gastrointestinal absorption of 95Nb by rats of different ages. Studies on iodine metabolism included the following: influence of thyroid status and thiocyanate on iodine metabolism in the bovine; effects of simulated fallout radiation on iodine metabolism in dairy cattle; and effects of feeding iodine binding agents on iodine metabolism in the calf

  9. An interspecies comparison of the biological effects of an inhaled, relatively insoluble beta emitter

    International Nuclear Information System (INIS)

    Mice, rats, Syrian hamsters, and beagle dogs were exposed by inhalation to graded levels of 144Ce in relatively insoluble forms to demonstrate species similarities and differences regarding patterns of deposition, fate, dosimetry, and dose-response relationships. All animals were serially evaluated to determine lung burdens, held for life-span observation, necropsied at death, and examined histopathologically to characterize the lesions present and to determine the cause of death. The primary malignant lung tumors observed in rodents were predominantly squamous-cell carcinomas and adenocarcinomas, whereas those in dogs at earlier times were primarily hemangiosarcomas and those in dogs that died at later times were pulmonary carcinomas. The relationship between the incidence of lung cancer and absorbed beta dose to the lung differed among species. The results of modeling these data provide a better understanding of how the choice of species can influence the outcome of a life-span study. The data are used to estimate the risk of lung cancer in man from an inhaled beta-emitting radionuclide. 26 refs., 5 figs., 6 tabs

  10. Probing new physics with underground accelerators and radioactive sources

    International Nuclear Information System (INIS)

    New light, weakly coupled particles can be efficiently produced at existing and future high-intensity accelerators and radioactive sources in deep underground laboratories. Once produced, these particles can scatter or decay in large neutrino detectors (e.g. Super-K and Borexino) housed in the same facilities. We discuss the production of weakly coupled scalars ϕ via nuclear de-excitation of an excited element into the ground state in two viable concrete reactions: the decay of the 0+ excited state of 16O populated via a (p,α) reaction on fluorine and from radioactive 144Ce decay where the scalar is produced in the de-excitation of 144Nd⁎, which occurs along the decay chain. Subsequent scattering on electrons, e(ϕ,γ)e, yields a mono-energetic signal that is observable in neutrino detectors. We show that this proposed experimental setup can cover new territory for masses 250 keV≤mϕ≤2me and couplings to protons and electrons, 10−11≤gegp≤10−7. This parameter space is motivated by explanations of the “proton charge radius puzzle”, thus this strategy adds a viable new physics component to the neutrino and nuclear astrophysics programs at underground facilities

  11. Determination of plutonium americium and curium in soil samples by solvent extraction with trioctylphosphine oxide

    International Nuclear Information System (INIS)

    A method of Pu, Am and Cm determination in soil samples, which was developed for analyzing samples from territories subjected to radioactive contamination as a result of the Chernobyl accident is described. After preliminary treatment the samples were leached by solution of 7 mol/l HNO23+0.3 mol/l KBrO3 during heating. Pu was isolated by extraction with 0.05 mol TOPO from 7 mol/l HNO3. 144Ce and partially remaining in water phase isotopes of Zr, U and Th were isolated in an extraction-chromatographic column with TOPO and PbO2. Then Am and Cm were extracted by 0.2 mol/l TOPO from solution 1 mol/l HLact+0.07 mol/l DTPA+1 mol/l Al(NO3)3. Alpha-activity of both extracted products was determined in liquid scintillation counter. Chemical yield of plutonium counted to 85±10%, that of americium and curium -75±10%. 17 refs

  12. Assay of long-lived radionuclides in low-level wastes from power reactors

    International Nuclear Information System (INIS)

    The 10 CFR Part 61 waste classification system includes several nuclides which are difficult to assay without expensive radiochemical methods. In order for waste generators to classify wastes practically, NRC Staff has recommended the use of correlation factors to scale the difficult-to-measure nuclides with nuclides which can be measured more easily (i.e., gamma emitters such as 60Co or 137Cs). In this study, Science Applications International Corporation (SAIC) performed complete radiochemical assays for all the 10 CFR Part 61 waste classification nuclides on over 100 samples. These data, along with almost 800 other samples in the SAIC data base, were used to assess the validity of correlation factors suggested for use in nuclear power plant wastes. Specific generic correlation factors are recommended with other approaches to correlate nuclides for which generic scaling factors are not defensible. The primary nuclide correlations studied were 14C, 55Fe, 59Ni, 63Ni, and 94Nb, with 60Co; 90Sr, 99Tc, 129I, 135Cs, and /sup 239, 240/Pu with 137Cs; 238Pu, /sup 239, 240/Pu, 241Pu, 241Am, 242Cm, and /sup 243, 244/Cm with 144Ce; and 238Pu, 241Pu, 241Am, 242Cm and /sup 243, 244/Cm with /sup 239, 240/Pu

  13. TMI-2 Reactor Building source term measurements: surfaces and basement water and sediment

    International Nuclear Information System (INIS)

    Presented in this report are the results of radiochemical and elemental analyses performed on samples collected from the Three Mile Island Unit 2 Reactor Building from August 1979 to December 1983. The quantities of fission products and core materials that were measured on the external surfaces in the Reactor Building or in the water and sediment in its basement are summarized. Recent analysis results for access panels removed from the air cooling assembly and for liquid and particulate samples collected from the Reactor Building sump and reactor coolant drain tank are included in the report. Measurements show that 59% of the 3H, 2.7% of the 90Sr, 15% of the 129I, 20% of the 131I, and 42% of the 137Cs originally in the core at the time of the accident could be accounted for outside the core in the Reactor Building. With the exceptions of 90Sr and 144Ce, the vast majority of each radionuclide released was found dispersed in the water and sediment in the basement

  14. Tumorigenic responses from single or repeated inhalation exposures to relatively insoluble aerosols of Ce-144

    International Nuclear Information System (INIS)

    Human occupational or environmental inhalation exposures may involve repeated or chronic exposures, but most laboratory studies of inhaled radionuclides have involved single exposures. This study was designed to compare the biological effects of repeated inhalation exposures of dogs to a relatively insoluble form of 144Ce with existing data for singly-exposed dogs that had the same cumulative dose to the lungs two years after exposure. To date, the biological effects observed in these repeatedly-exposed dogs have been substantially different from those seen in singly-exposed dogs, particularly during the first 5 years after the initial exposure. Although pulmonary hemangiosarcoma was the prominent biological effect seen in singly-exposed dogs between 2 and 4 years after exposure, no lung tumors were seen during the 5 years after the first of the repeated exposures. This response plus other clinical observations are discussed in relation to the patterns of dose rate and cumulative dose for the different exposure conditions. (H.K.)

  15. TMI-2 Reactor Building source term measurements: surfaces and basement water and sediment

    Energy Technology Data Exchange (ETDEWEB)

    McIsaac, C V; Keefer, D G

    1984-10-01

    Presented in this report are the results of radiochemical and elemental analyses performed on samples collected from the Three Mile Island Unit 2 Reactor Building from August 1979 to December 1983. The quantities of fission products and core materials that were measured on the external surfaces in the Reactor Building or in the water and sediment in its basement are summarized. Recent analysis results for access panels removed from the air cooling assembly and for liquid and particulate samples collected from the Reactor Building sump and reactor coolant drain tank are included in the report. Measurements show that 59% of the /sup 3/H, 2.7% of the /sup 90/Sr, 15% of the /sup 129/I, 20% of the /sup 131/I, and 42% of the /sup 137/Cs originally in the core at the time of the accident could be accounted for outside the core in the Reactor Building. With the exceptions of /sup 90/Sr and /sup 144/Ce, the vast majority of each radionuclide released was found dispersed in the water and sediment in the basement.

  16. Radionuclide migration experiments in a natural fracture in a quarried block of granite

    International Nuclear Information System (INIS)

    A radionuclide migration experiment was performed over a distance of 1 m in a natural fracture in a quarried block of granite. The fracture in the block was characterized hydraulically by measuring the pressure drop in borehole-to-borehole pump tests. The effective fracture volume in the block was ∼100 mL. A silicone coating was applied to the exterior, and the block was immersed in a tank of water to which hydrazine was added to provide a chemically reducing barrier. Migration experiments were performed at a flow rate of 2.2 mL h-1 using 85Sr, 131I,137Cs, 144Ce, 152Eu, 237Np and 238Pu. A total of 9.5 L of groundwater was pumped through the fracture, corresponding to ∼95 fracture volumes. Only 85Sr, 131I, 137Cs, 237Np and 238Pu were observed in the eluent. Scanning of the fracture surface at the end of the migration experiment showed limited mobility of α-emitting radionuclides and of the rare-earth elements, consistent with static sorption data obtained on representative fracture surface material. The mobility of 137Cs was higher than that of the rare-earth elements, but it was lower than that of 85Sr. When samples of fracture-coating material were separated into fractions with different specific gravity, there was a clear indication of radionuclide association with mineral groups. (author)

  17. Radionuclide migration experiments in a natural fracture in a quarried block of granite

    Science.gov (United States)

    Vandergraaf, Tjalle T.; Drew, Douglas J.; Masuda, Sumio

    1996-02-01

    A radionuclide migration experiment was performed over a distance of 1 m in a natural fracture in a quarried block of granite. The fracture in the block was characterized hydraulically by measuring the pressure drop in borehole-to-borehole pump tests. The effective fracture volume in the block was ˜ 100 mL. A silicone coating was applied to the exterior, and the block was immersed in a tank of water to which hydrazine was added to provide a chemically reducing barrier. Migration experiments were performed at a flow rate of 2.2 mL h -1 using 85Sr, 131I, 137Cs, 144Ce, 152Eu, 237Np and 238Pu. A total of 9.5 L of groundwater was pumped through the fracture, corresponding to ˜95 fracture volumes. Only 85Sr, 131I, 137Cs, 237Np and 238Pu were observed in the eluent. Scanning of the fracture surface at the end of the migration experiment showed limited mobility of α-emitting radionuclides and of the rare-earth elements, consistent with static sorption data obtained on representative fracture surface material. The mobility of 137Cs was higher than that of the rare-earth elements, but it was lower than that of 85Sr. When samples of fracture-coating material were separated into fractions with different specific gravity, there was a clear indication of radionuclide association with mineral groups.

  18. Study of the behaviour of transuranics and possible chemical homologues in Lake Michigan water and biota

    International Nuclear Information System (INIS)

    Concentration factors for Pu, Am and U in Lake Michigan biota are compared to those of a number of stable trace elements that have short residence times in Lake Michigan water. The relative order of uptake for these nuclides in Lake Michigan biota is Am>Pu much>U. Evidence is summarized which suggests that the predominant oxidation state of 239, 240Pu in Lake Michigan water is 4+. Concentrations of 239, 240Pu in net plankton, filterable particulate matter, sediment trap, and benthic floc samples indicate that sorption by biogenic detritus, and settling of this material, can account for the reduced concentration of 239, 240Pu observed in surface waters during summer stratification, but that deposition into the sediments is primarily non-biological. Concentrations of 7Be, 144Ce and 137Cs in sediment trap samples show the effect of spring convective mixing and demonstrate the resuspension of mineral-rich surficial sediments during the summer months. The effect on the concentration of dissolved plutonium in the water column, of varying degrees of resuspension of sedimentary floc, is described using a simple mass-action model. A radiochemical method for the determination of americium and uranium in Lake Michigan environmental samples is also presented. (author)

  19. Calibration of Ge(Li) semiconductor detector by method using agar volume source

    International Nuclear Information System (INIS)

    The Ge(Li) semiconductor detector was calibrated for measurements of environmental samples. The radioisotopes used for standard sources are 22Na, 51Cr, 56Co, 57Co, 133Ba, 137Cs, 144Ce and 241Am. These are mixed with hot agar aqueous solution and fixed uniformly in a cylindrical plastic case in cooling. The agar volume source is advantageous in handling over the fluid aqueous source. The prepared cylindrical standard sources are in diameters 6 and 8 cm and thicknesses 1, 5, 10, 20, 30 and 40 mm (only for 8 cm diameter). The radioactivities of prepared standard sources are between 0.03 μCi and 0.2 μCi. It takes only a week to make the calibration except data processing. The obtained full energy peak efficiency curves include 5 - 10% error due to preparation of agar source, reference radioactivity data of purchased standard solutions, reference data of branching ratio of gamma-ray and sum effect. The efficiency curves, however, are sufficient for quantitative analysis of environmental samples. (author)

  20. Long-lived radionuclides in low-level waste

    International Nuclear Information System (INIS)

    In July 1982, the Low-Level Waste Licensing Branch of the NRC, anticipating the impact of the proposed Part 61 to 10 CFR, funded a two-year project by SAI to study the radionuclide contents of LWR generated in low-level waste. The objectives of the study are: (1) to analyze, using verified techniques, 150 archived samples for specified beta- and x-ray-emitting nuclides that had not previously been analyzed; (2) to analyze twenty new samples obtained from operating plants for all relevant nuclides and compare them to previous data to ascertain trends; (3) to develop empirical scaling factors through the use of which concentrations of hard-to-analyze nuclides can be estimated from analyses of the gamma-ray emitting nuclides. The new samples are analyzed and the results are summarized and interpreted. Over fifty archived samples have also been analyzed. We discuss scaling factor development. Factors are presented that relate 63Ni and 59Ni to 60Co for PWRs and to 58Co for BWRs, 90Sr to 137Cs for BWRs and 241Pu, 239Pu, 241Am, and 244Cm to 144Ce for all LWRs. 8 figures, 3 tables

  1. Marine plankton as an indicator of low-level radionuclide contamination in the Southern Ocean

    International Nuclear Information System (INIS)

    We have initiated an investigation of the utility of marine plankton as bioconcentrating samplers of low-level marine radioactivity in the southern hemisphere. A literature review shows that both freshwater and marine plankton have trace element and radionuclide concentration factors (relative to water) of up to 104. In the years 1956-1958, considerable work was done on the accumulation and distribution of a variety of fission and activation products produced by the nuclear tests in the Marshall Islands. Since then, studies have largely been confined to a few selected radionuclides, and by far most of this work has been done in the northern hemisphere. We participated in Operation Deepfreeze 1981, collecting 32 plankton samples from the U.S. Coast Guard Cutter Glacier on its Antarctic cruise, while Battelle Pacific Northwest Laboratories concurrently sampled air, water, rain and fallout. We were able to measure concentrations of the naturally occurring radionuclides 7Be, 40K and the U and th series, and we believe that we have detected low levels of 144Ce and 95Nb in seven samples ranging as far south as 680. There is a definite association between the radionuclide content of plankton and air filters, suggesting that aerosol resuspension of marine radioactivity may be occurring. Biological identification of the plankton suggests a possible correlation between radionuclide concentration and foraminifera content of the samples. 38 references, 7 figures, 3 tables

  2. Fission-Product Development Laboratory cell-decommissioning project plan

    International Nuclear Information System (INIS)

    The Fission Product Development Laboratory (FPDL) at Oak Ridge National Laboratory (ORNL) was a full-scale processing facility for separating megacurie quantities of 90Sr, 137Cs, and 144Ce for a variety of source applications, operating at full capacity from 1958 to 1975. Since facility shutdown, the inactive portions of the FPDL have been maintained in a protective storage mode as part of the ORNL Surplus Facilities Management Program (SFMP). Due to the significant radio-nuclide inventory remaining in the facility, the high surveillance and maintenance costs necessary to assure radionuclide containment, and the potential for reuse of the facility by other programs, the decommissioning of the inactive portions of the FPDL has been given a high priority by the SFMP. In response to this program direction, plans are being made for initiation of these activities in late FY 1983. This project plan has been prepared to satisfy the program documentation requirements for SFMP project planning. The plan outlines the scope of the proposed effort, describes the proposed methods of project accomplishment, and provides estimates of the project resource needs and schedule

  3. Classification of hot particles from the Chernobyl accident and nuclear weapons detonations by non-destructive methods

    International Nuclear Information System (INIS)

    Both after the Chernobyl accident and nuclear weapon detonations, agglomerates of radioactive material, so-called hot particles, were released or formed which show a behaviour in the environment quite different from the activity released in gaseous or aerosol form. The differences in their characteristic properties, in the radionuclide composition and the uranium and actinide contents are described in detail for these particles. While nuclear bomb hot particles (both from fission and fusion bombs) incorporate well detectable trace amounts of 60Co and 152Eu, these radionuclides are absent in Chernobyl hot particles. In contrast, Chernobyl hot particles contain 125Sb and 144Ce which are absent in atomic bomb HPs. Obvious differences are also observable between fusion and fission bombs' hot particles (significant differences in 152Eu/155Eu, 154Eu/155Eu and 238Pu/239Pu ratios) which facilitate the identification of HPs of unknown provensence. The ratio of 239Pu/240Pu in Chernobyl hot particles could be determined by a non-destructive method at 1:1.5. A non-destructive method to determine the content of non-radioactive elements by Kα-emission measurements was developed by which inactive Zr, Nb, Fe and Ni could be verified in the particles

  4. Linear free energy correlations for fission product release from the Fukushima-Daiichi nuclear accident.

    Science.gov (United States)

    Abrecht, David G; Schwantes, Jon M

    2015-03-01

    This paper extends the preliminary linear free energy correlations for radionuclide release performed by Schwantes et al., following the Fukushima-Daiichi Nuclear Power Plant accident. Through evaluations of the molar fractionations of radionuclides deposited in the soil relative to modeled radionuclide inventories, we confirm the initial source of the radionuclides to the environment to be from active reactors rather than the spent fuel pool. Linear correlations of the form In χ = −α ((ΔGrxn°(TC))/(RTC)) + β were obtained between the deposited concentrations, and the reduction potentials of the fission product oxide species using multiple reduction schemes to calculate ΔG°rxn (TC). These models allowed an estimate of the upper bound for the reactor temperatures of TC between 2015 and 2060 K, providing insight into the limiting factors to vaporization and release of fission products during the reactor accident. Estimates of the release of medium-lived fission products 90Sr, 121mSn, 147Pm, 144Ce, 152Eu, 154Eu, 155Eu, and 151Sm through atmospheric venting during the first month following the accident were obtained, indicating that large quantities of 90Sr and radioactive lanthanides were likely to remain in the damaged reactor cores. PMID:25675358

  5. Linear free energy correlations for fission product release from the Fukushima-Daiichi nuclear accident.

    Science.gov (United States)

    Abrecht, David G; Schwantes, Jon M

    2015-03-01

    This paper extends the preliminary linear free energy correlations for radionuclide release performed by Schwantes et al., following the Fukushima-Daiichi Nuclear Power Plant accident. Through evaluations of the molar fractionations of radionuclides deposited in the soil relative to modeled radionuclide inventories, we confirm the initial source of the radionuclides to the environment to be from active reactors rather than the spent fuel pool. Linear correlations of the form In χ = −α ((ΔGrxn°(TC))/(RTC)) + β were obtained between the deposited concentrations, and the reduction potentials of the fission product oxide species using multiple reduction schemes to calculate ΔG°rxn (TC). These models allowed an estimate of the upper bound for the reactor temperatures of TC between 2015 and 2060 K, providing insight into the limiting factors to vaporization and release of fission products during the reactor accident. Estimates of the release of medium-lived fission products 90Sr, 121mSn, 147Pm, 144Ce, 152Eu, 154Eu, 155Eu, and 151Sm through atmospheric venting during the first month following the accident were obtained, indicating that large quantities of 90Sr and radioactive lanthanides were likely to remain in the damaged reactor cores.

  6. Benefits and risks of bronchopulmonary lavage: a review

    International Nuclear Information System (INIS)

    Studies were conducted in beagle dogs and baboons over a period of 20 years to determine the efficiency of treatment by lung lavage after inhalation of insoluble radioactive particles. The radionuclides tested were 144Ce in fused clay, 238Pu, 239Pu, 241Am, Pu-TBP, Pu02, UO2, and (Pu,U)02. After inhalation of any of these radionuclides, a single lavage of the two lungs removed almost a quarter of the intitial lung burden (ILB) in the two species. When lavage was repeated five times, it removed up to half of the ILB. However, the individual variation was large. For the same radionuclide, lavage efficiency was independent of the ILB. Particle removal was better and continued longer for particles with a long retention half-time. The use of lavage can be combined with that of chelating agents like DTPA. The removal of radioactive particles lenghtened survival time and reduced the severity of pathology. The lavage in itself is safe, and does not induce permanent or progressive pathology. The biomedical risk of the lavage mainly depends on the risks inherent in anaesthesia and the health status of the patient. (author)

  7. Speciation and transport of radionuclides in ground water

    International Nuclear Information System (INIS)

    Studies of the chemical speciation of a number of radionuclides migrating in a slightly contaminated ground water plume are identifying the most mobile species and providing an opportunity to test and/or validate geochemical models of radionuclide transport in ground waters. Results to date have shown that most of the migrating radionuclides are present in anionic or nonionic forms. These include anionic forms of 55Fe, 60Co, /sup 99m/Tc, 106Ru, 131I, and nonionic forms of 63Ni and 125Sb. Strontium-70 and a small fraction of the mobile 60Co are the only cationic radionuclides which have been detected moving in the ground water plume beyond 30 meters from the source. A comparison of the observed chemical forms with the predicted species calculated from modeling thermodynamic data and ground water chemical parameters has indicated a good agreement for most of the radioelements in the system, including Tc, Np, Cs, Sr, Ce, Ru, Sb, Zn, and Mn. The discrepancies between observed and calculated solutions species were noted for Fe, Co, Ni and I. Traces of Fe, Co, and Ni were observed to migrate in anionic or nonionic forms which the calculations failed to predict. These anionic/nonionic species may be organic complexes having enhanced mobility in ground waters. The radioiodine, for example, was shown to behave totally as an anion but further investigation revealed that 49-57% of this anionic iodine was organically bound. The ground water and aqueous extracts of trench sediments contain a wide variety of organic compounds, some of which could serve as complexing agents for the radionuclides. These results indicate the need for further research at a variety of field sites in defining precisely the chemical forms of the mobile radionuclide species, and in better understanding the role of dissolved organic materials in ground water transport of radionuclides

  8. Kinetics of ruthenium in humans

    International Nuclear Information System (INIS)

    The fission products 103Ru and 106Ru may represent a radiological hazard for the population in case of their release in the environment and transfer to the food chain; considerable amounts of these radionuclides were indeed found in the fall-out of the Chernobyl accident and also after nuclear weapon tests. As for many other radionuclides, the biokinetic model for ruthenium currently recommended by ICRP is mainly based on animal data. In order to obtain valuable information directly in humans, a technique based on stable isotopes administration and analytical methods such as activation analysis with charged particles and inductively coupled mass spectrometry has been purposely developed. A total of six investigations were conducted on two healthy volunteers by administration of given amounts of isotopically enriched ruthenium. Blood samples were withdrawn at fixed intervals in the first 6 hours after administration, and the total renal excretion in the first two days collected. Tracer concentration in the biological samples were determined using the analytical methods introduced above. The results show that the kinetics in plasma and the urinary pattern present several deviation from the behaviour described by the current ICRP model. The intestinal absorption proceeds at a faster rate, however the fraction absorbed dose not differ greatly from the value of 0.05 recommended. The excretion in the urine is on the contrary greatly reduced, which could suggest that Ru radionuclides may be retained more efficiently in the body. These differences could have significant impact on the calculation of dose coefficient after incorporation of Ru radionuclides. (author)

  9. Study of the ruthenium fission-product behavior in the containment, in the case of a nuclear reactor severe accident; Etude du comportement du produit de fission ruthenium dans l'enceinte de confinement d'un reacteur nucleaire, en cas d'accident grave

    Energy Technology Data Exchange (ETDEWEB)

    Mun, Ch

    2007-03-15

    Ruthenium tetroxide is an extremely volatile and highly radio-toxic species. During a severe accident with air ingress in the reactor vessel, ruthenium oxides may reach the reactor containment building in significant quantities. Therefore, a better understanding of the RuO{sub 4}(g) behaviour in the containment atmosphere is of primary importance for the assessment of radiological consequences, in the case of potential releases of this species into the environment. A RuO{sub 4}(g) decomposition kinetic law was determined. Steam seems to play a catalytic role, as well as the presence of ruthenium dioxide deposits. The temperature is also a key parameter. The nature of the substrate, stainless steel or paint, did not exhibit any chemical affinities with RuO{sub 4}(g). This absence of reactivity was confirmed by XPS analyses, which indicate the presence of the same species in the Ru deposits surface layer whatever the substrates considered. It has been concluded that RuO{sub 4}(g) decomposition corresponds to a bulk gas phase decomposition. The ruthenium re-volatilization phenomenon under irradiation from Ru deposits was also highlighted. An oxidation kinetic law was determined. The increase of the temperature and the steam concentration promote significantly the oxidation reaction. The establishment of Ru behavioural laws allowed making a modelling of the Ru source term. The results of the reactor calculations indicate that the values obtained for {sup 106}Ru source term are closed to the reference value considered currently by the IRSN, for 900 MWe PWR safety analysis. (author)

  10. Off-gas treatment and characterization for a radioactive in situ vitrification test

    International Nuclear Information System (INIS)

    Effluents released to the off gas during the in situ vitrification (ISV) of a test site have been characterized. The site consisted of a 19 L waste package of soil containing 600 nCi/g transuranic and 30,000 nCi/g mixed fission products surrounded by uncontaminated soil. Radioactive isotopes present in the package were 241Am, /sup 238/239/Pu, 137Cs, 106Ru, 90Sr, and 60Co. The ISV process melted the waste package and surrounding soil and immobilized the radionuclides in place, producing a durable, 8.6 metric ton glass and crystalline monolith. The test successfully demonstrated that the process provides containment of radioactive material. No release to the environment was detected during processing or cooldown. Due to the high temperatures during processing, some gases were released into the off-gas hood that was placed over the test site. The hood was maintained at a light negative pressure to contain any volatile or entrained material during processing. Gases passed from the hood to an off-gas treatment system where they were treated using a venturi-ejector scrubber, a tandem nozzle gas cleaner scrubber followed by a condenser, heater, and two stages of HEPA filters. The off-gas treatment system is located in the semi-trailer to allow transport of the process to other potential test sites. Retention of all radionuclides by the vitrified zone was greater than 99%. Soil-to-off-gas decontamination factors (DFs) for transuranic elements averaged greater than 4000 and for fission products, DFs ranged from 130 for 137Cs to 3100 for 90Sr

  11. The potentialities of the complexation ultrafiltration technique for the decontamination of fission product contaminated aqueous effluents

    International Nuclear Information System (INIS)

    Many nuclear researchers and industrial operators lay emphasis on improving the back end of the fuel cycle. A major problem concerns the liquid wastes generated by the reprocessing plant at La Hague, discharged into the sea after treatment in the Effluent Treatment Station (STE) 3), and which have become crucial matter. The activity of these wastes is well below the current legal limits, and is constantly decreasing these last years. To bring it close to zero, and ambitious goal, entails innovative new reprocessing techniques. We accordingly investigated the possibilities of complexation-ultrafiltration, a technique that uses water-soluble macromolecules to complex the target elements to be separated. We first achieved the strontium (II) separation with poly-acrylic and poly-sulfonic acids. The effects of pH and NaNO3 concentration influence on Sr (II) complexation were studied. The Sr (II) complexation and concentration phases, followed by cation de-complexation to recover the polymer, were also taken into account. This research, combined with a potentiometric study of the polymers, offered a close understanding of the chemical systems involved, and of the operating conditions and limits of complexation-ultrafiltration. The laboratory results were also validated on a tangential ultrafiltration pilot plant. We then used complexation-ultrafiltration to treat a real effluent generated bu La Hague's STE 3 plant. This experiment demonstrated minimum 90 % decontamination of Sr (II) (with polyacrylate complexing agent), and also for 134-137Cs (with simple ultrafiltration). The use of two polyamides allowed partial decontamination of the effluent for 60Co and 106Ru. This work therefore offers a global approach to complexation-ultrafiltration, from laboratory to pilot scale, on real and simulated effluents. The future of this technique relies chiefly on the ability to solve the problem of polymer recovery. In other respect, complexation-ultrafiltration clearly offers a

  12. The potentialities of the complexation ultrafiltration technique for the decontamination of fission product contaminated aqueous effluents; Potentialites de la complexation - ultrafiltration a la decontamination d`effluents radioactifs en produits de fission

    Energy Technology Data Exchange (ETDEWEB)

    Thibert, V.

    1995-07-01

    Many nuclear researchers and industrial operators lay emphasis on improving the back end of the fuel cycle. A major problem concerns the liquid wastes generated by the reprocessing plant at La Hague, discharged into the sea after treatment in the Effluent Treatment Station (STE) (3), and which have become crucial matter. The activity of these wastes is well below the current legal limits, and is constantly decreasing these last years. To bring it close to zero, and ambitious goal, entails innovative new reprocessing techniques. We accordingly investigated the possibilities of complexation-ultrafiltration, a technique that uses water-soluble macromolecules to complex the target elements to be separated. We first achieved the strontium (II) separation with poly-acrylic and poly-sulfonic acids. The effects of pH and NaNO{sub 3} concentration influence on Sr (II) complexation were studied. The Sr (II) complexation and concentration phases, followed by cation de-complexation to recover the polymer, were also taken into account. This research, combined with a potentiometric study of the polymers, offered a close understanding of the chemical systems involved, and of the operating conditions and limits of complexation-ultrafiltration. The laboratory results were also validated on a tangential ultrafiltration pilot plant. We then used complexation-ultrafiltration to treat a real effluent generated bu La Hague`s STE 3 plant. This experiment demonstrated minimum 90 % decontamination of Sr (II) (with polyacrylate complexing agent), and also for {sup 134-137}Cs (with simple ultrafiltration). The use of two polyamides allowed partial decontamination of the effluent for {sup 60}Co and {sup 106}Ru. This work therefore offers a global approach to complexation-ultrafiltration, from laboratory to pilot scale, on real and simulated effluents. The future of this technique relies chiefly on the ability to solve the problem of polymer recovery. (Abstract Truncated)

  13. Urban radionuclide contamination studied in sewage water and sludge from Lund and Gothenburg

    International Nuclear Information System (INIS)

    The concentrations of various radionuclides have been measured in the sewage treatment plant serving the town of Lund in southern Sweden. The incoming water, the outgoing water and the sludge have been studied. The measurements started already in 1983 and have gone on since then, which means both before and after the Chernobyl accident. After the accident the concentration of radionuclides was also measured at Gothenburg in western Sweden. The total deposition of the various radionuclides was almost the same 2 kBq/m2 at Lund and Gothenburg although the temporal distribution was somewhat different. The activity concentration measured in the sludge reached a peak value of 87.1 kBq/kg (d.w) for 106Ru and 3.8 kBq/kg for 137Cs at Gothenburgh and of 15.4 and 12.1 k/Bq/kg respectively at Lund. These activity concentrations were measured about 2-3 days after at Lund. The differences in the delays are due to differences in the construction of the plants. The close investigation of the sewage treatment plant at Lund makes it possible to state that about 50 per cent of the incoming 137Cs leaves the plant with the outgoing sludge. It is reasonable to believe that 50 per cent also is valid for the plant at Gothenburg. At Lund the total yearly outgoing activity of 137Cs has fallen exponentially from 900 MBq in 1986 to 100 MBq in 1989. An extrapolation reveals that the activity concentration will be back to pre-Chernobyl levels in 1992/93. But of the original deposition of 12.400 MBq 2/3 or 8.200 MBq will still be left. The same retention factor most probably goes for Gothenburg too. (authors)

  14. Effect of uncertainty in nasal airway deposition of radioactive particles on effective dose

    Energy Technology Data Exchange (ETDEWEB)

    Guilmette, R.A.; Birchall, A.; Jarvis, N.S

    1998-07-01

    In the current ICRP human respiratory tract (RT) model (ICRP Publication 66), the deposition of particles in various regions of the RT during natural breathing is modelled by considering the RT as a series of filters, resulting in deposition probabilities for distal portions of the RT being dependent on those of the proximal segments. Thus, uncertainties in regional deposition in proximal segments of the RT are reflected or propagated in uncertainties in deposition in the distal segments of the lung. Experimental data on aerosol particle deposition have demonstrated significant variability in nasal airway (NA) deposition for different individuals studied. This report summarises the impact of introducing variability in NA deposition efficiency on the calculation of effective doses using the ICRP 66 model for selected radionuclides. The computer software LUDEP, modified for this purpose, was used to customise deposition patterns, and effective doses were calculated for several radionuclides ({sup 111}In, {sup 106}Ru, {sup 60}Co, {sup 210}Po, {sup 238}U and {sup 239}Pu) chosen to represent isotopes with various decay schemes and half-lives. The results indicated significant but particle-size-specific effects of assumed NA deposition efficiencies on the calculated effective doses, which varied typically by factors of five to six. The majority of the variability was associated with direct effects on deposition patterns, but in some cases, alterations of radiation dose distribution within the various target organs also contributed to the variability. These results provide a basis for evaluating uncertainties due to inter-individual differences in deposition patterns for radiation protection and risk analysis. (author)

  15. Field and model investigations of external gamma dose rates along the Cumbrian coast, NW England

    Energy Technology Data Exchange (ETDEWEB)

    McDonald, P [Environmental Sciences, Westlakes Scientific Consulting Limited, Westlakes Science and Technology Park, Moor Row, Cumbria CA24 3LN (United Kingdom); Bryan, S E [Environmental Sciences, Westlakes Scientific Consulting Limited, Westlakes Science and Technology Park, Moor Row, Cumbria CA24 3LN (United Kingdom); Hunt, G J [Centre for Environment, Fisheries and Aquaculture Science, CEFAS Lowestoft Laboratory, Pakefield Road, Lowestoft, Suffolk NR33 0HT (United Kingdom); Baldwin, M [Centre for Environment, Fisheries and Aquaculture Science, CEFAS Lowestoft Laboratory, Pakefield Road, Lowestoft, Suffolk NR33 0HT (United Kingdom); Parker, T G [British Nuclear Group, Sellafield, Seascale, Cumbria CA20 1PG (United Kingdom)

    2005-03-01

    A survey of the contribution to external dose from gamma rays originating from intertidal sediments in the vicinity of the British Nuclear Group Sellafield site showed that the major anthropogenic contributions were due to {sup 137}Cs and {sup 60}Co. At some sites, traces of other anthropogenic radionuclides were detected, namely {sup 106}Ru, {sup 125}Sb, and {sup 154}Eu. The proportions of fine grained material (<63 {mu}m) were used to improve model predictions of dose contribution due to external exposure to gamma rays, using the CUMBRIA77/DOSE77 model. Model dose predictions were compared to those directly measured in the field. Using the new proportions of fine grained material (1-17.5%) in conjunction with field gamma-ray spectra, model predictions were improved considerably for most sites. Exceptions were at Drigg Barn Scar and Whitehaven Coal Sands sites, which had their own unique characteristics. The highest {sup 60}Co activity concentrations in this study were detected at Drigg Barn Scar. These relatively high activity concentrations of {sup 60}Co were due to the presence of {sup 60}Co in mussels and barnacles, hence upsetting the fine sediment relationships used in previous dose calculations. Whitehaven Coal Sands was unusual in that it contained higher levels of radionuclides than would be expected in sandy sediment. The mineralogy of these sediments was the controlling factor on {sup 137}Cs binding, rather than the proportion of fine grained material. By adjusting the effective fine grained sediment proportions for calculations involving {sup 60}Co and {sup 137}Cs at Drigg Barn Scar and Whitehaven Coal Sands respectively, the CUMBRIA77/DOSE77 model predictions could be improved upon significantly for these sites. This work highlights the influence of particle size and sediment composition on external dose rate calculations, as well as the potential for external dose contributions from biota.

  16. Preparation, characterisation and evaluation of nano MnO2 for uptake of alpha contaminants from radioactive liquid waste

    International Nuclear Information System (INIS)

    Radioactive liquid waste is generated during reprocessing of spent nuclear fuel, which is classified as, low level liquid waste (LLW), intermediate level waste (ILW) and high level waste (HLW) based on radioactivity concentration. The strategy for management of LLW and ILW lies in the development and deployment of innovative processes having volume reduction as one of the important parameter. For achieving volume reduction, methodologies based on separation science such as ion exchange, adsorption, extraction etc. are used. Effluents generated during such treatment of LLW will have small concentration of radionuclides like 137Cs, 90Sr, 106Ru, 238U, 239Pu, 241Am etc. These waste streams require treatment to further reduce their activity content following near zero discharge approach. Nano-materials based on the mineral oxides of Si, Al, Ti, Mn, etc., are used as sorbents for heavy metal ions present in waste waters. Oxidative nature of MnO2 has been shown to regulate the concentration of some of the toxic metal ions, viz., Cr, Pb, in estuarine waters. Keeping these properties of MnO2 in mind, in the present study, nanocrystalline manganese oxide was prepared by hydrolysis of potassium permanganate by ethanol. A FT-IR spectrum of the powder was recorded to ensure that there is no organic impurity in the sample due to the alcoholic hydrolysis process. The oxide obtained was characterized for phase analysis and crystallite size estimation using X-ray diffraction technique. The average crystallite size calculated from the Scherrer's formula was found to be ∼ 4 to 8 nm, which is further confirmed from the TEM micrographs. The nano MnO2was evaluated for the sorption characteristics of Pu

  17. Laboratory development of methods for centralized treatment of liquid low-level waste at Oak Ridge National Laboratory

    International Nuclear Information System (INIS)

    Improved centralized treatment methods are needed in the management of liquid low-level waste (LLLW) at Oak Ridge National Laboratory (ORNL). LLLW, which usually contains radioactive contaminants at concentrations up to millicurie-per-liter levels, has accumulated in underground storage tanks for over 10 years and has reached a volume of over 350,000 gal. These wastes have been collected since 1984 and are a complex mixture of wastes from past nuclear energy research activities. The waste is a highly alkaline 4-5 M NaNO3 solution with smaller amounts of other salts. This type of waste will continue to be generated as a consequence of future ORNL research programs. Future LLLW (referred to as newly generated LLLW or NGLLLW) is expected to a highly alkaline solution of sodium carbonate and sodium hydroxide with a smaller concentration of sodium nitrate. New treatment facilities are needed to improve the manner in which these wastes are managed. These facilities must be capable of separating and reducing the volume of radioactive contaminants to small stable waste forms. Treated liquids must meet criteria for either discharge to the environment or solidification for onsite disposal. Laboratory testing was performed using simulated waste solutions prepared using the available characterization information as a basis. Testing was conducted to evaluate various methods for selective removal of the major contaminants. The major contaminants requiring removal from Melton Valley Storage Tank liquids are 90Sr and 137Cs. Principal contaminants in NGLLLW are 9OSr, 137Cs, and 106Ru. Strontium removal testing began with literature studies and scoping tests with several ion-exchange materials and sorbents

  18. Relation between physicomechanical properties and diffusion phenomena in composite materials

    International Nuclear Information System (INIS)

    One of the procedures for storing low and medium activity nuclear waste consists of coating the contaminated material in a thermosetting resin. The drums thus constitued are stored in concreted underground trenches, then covered with cement, bitumen or clayey soil. Although the risk of water circulation is low, this element represents on the one hand the major cause of natural deterioration of the polymer, and on the other hand the most likely vehicle for conveying the radioactive ions confined in the drums. It is for this reason that the study of the behaviour of polyester or epoxide-based macromolecular materials with regard to water constitutes the first stage of this work. The second part of the thesis is directed towards the study of compound materials. Indeed, the charges are represented in the first case by the nuclear waste itself; in the second case, they are introduced into the polymer beforehand, on the one hand to reduce costs, and on the other hand to give the mixture suitable mechanical and rheological properties. In this study, three types of mineral charge are added in an epoxide resin: glass balls surface-treated or not, and sand. Various techniques are implemented in order to assess and characterize the interfacial adhesion, in the different systems. The strongest polymer-charge bonds are sought in order to resist natural deterioration. Finally, the object of the confinement process, is to avoid dispersion of low and medium activity substances (137Cs, 90Sr, 60Co, 106Ru..) in the environment. The final stage of this work therefore consists in assessing the barrier qualities of pure or charged polymers with regard to radioactive ion diffusion. We will show in particular that the use of fine resin membranes enables the diffusion coefficient of the 137Cs to be calculated

  19. Data summary report for fission product release test VI-4

    International Nuclear Information System (INIS)

    This was the fourth in a series of high-temperature fission product release tests in a vertical test apparatus. The test specimen, a 15.2-cm-long section of a fuel rod from the BR3 reactor in Belgium, had been irradiated to a burnup of 47 MWd/kg. In simulation of a severe accident in a light-water reactor, it was heated in hydrogen in a hot cell-mounted test apparatus to a maximum test temperature of 2400 K for a period of 20 min. The released fission products were collected on components designed to facilitate sampling and analysis. On-line radioactivity measurements and posttest inspection revealed that the fuel had partially collapsed at about the time the cladding melted. Based on fission product inventories measured in the fuel or calculated by ORIGEN2, analyses of test components showed total releases from the fuel of 85% for 85Kr, 106Ru, 3.9% for 125Sb, 96% for both 134Cs and 137Cs, and 13% for 154Eu. Large fractions of the released fission products (up to 96% of the 154Eu) were retained in the furnace. Small release fractions for several other fission products -- Rb, Br, Sr, Te, I, and Ba -- were detected also. In addition, very small amounts of fuel material -- uranium and plutonium -- were released. Total mass release from the furnace to the collection system, which included fission products, fuel material, and structural materials, was 0.40g, with 40% of this material being deposited as vapor and 60% of it being collected as aerosols. The results from this test were compared with previous tests in this series and with an in-pile test at similar conditions at Sandia National Laboratories. There was no indication that the mode of heating (fission heat vs radiant heat) significantly affected fission product release. 24 refs., 25 figs., 14 tabs

  20. Off-gas treatment and characterization for a radioactive in situ vitrification test

    International Nuclear Information System (INIS)

    Effluents released to the off gas during the in situ vitrification (ISV) of a test site have been characterized by Pacific Northwest Laboratory. The site consisted of a 19 L waste package of soil containing 600 nCi/g transuranic and 30,000 nCi/g mixed fission products surrounded by uncontaminated soil. Radioactive isotopes present in the package were 241Am, 238/239Pu, 137Cs, 106Ru, 90Sr, and 60Co. The ISV process melted the waste package and surrounding soil and immobilized the radionuclides in place, producing a durable, 8.6 metric ton glass and crystalline monolith. The test successfully demonstrated that the process provides containment of radioactive material. No release to the environment was detected during processing of cooldown. Due to the high temperature during processing, some gases were released into the off-gas hood that was over the test site. The hood was maintained at a slight negative pressure to contain any volatile or entrained material during processing. Gases passed from the hood to an off-gas treatment system where they were treated using a venturi-ejector scrubber, a tandem nozzle gas cleaner scrubber followed by a condenser, heater, and two stages of HEPA filters. The off-gas treatment system is located in the semi-trailer to allow transport of the process to other potential test sites. Retention of all radionuclides by the vitrified zone was greater than 99%. Soil-to-off-gas decontamination factors (DFs) for transuranic elements averaged greater than 4000 and for fission products, DFs ranged from 130 for 137Cs to 3100 for 90Sr. 7 references, 15 figures, 4 tables

  1. Determination of the Ce142(γ,n) cross section using quasi-monoenergetic Compton backscattered γ rays

    Science.gov (United States)

    Sauerwein, A.; Sonnabend, K.; Fritzsche, M.; Glorius, J.; Kwan, E.; Pietralla, N.; Romig, C.; Rusev, G.; Savran, D.; Schnorrenberger, L.; Tonchev, A. P.; Tornow, W.; Weller, H. R.

    2014-03-01

    Background: Knowing the energy dependence of the (γ,n) cross section is mandatory to predict the abundances of heavy elements using astrophysical models. The data can be applied directly or used to constrain the cross section of the inverse (n,γ) reaction. Purpose: The measurement of the reaction Ce142(γ,n)141Ce just above the reaction threshold amends the existing experimental database in that mass region for p-process nucleosynthesis and helps to understand the s-process branching at the isotope Ce141. Method: The quasi-monoenergetic photon beam of the High Intensity γ-ray Source (HIγS), TUNL, USA, is used to irradiate naturally composed Ce targets. The reaction yield is determined afterwards with high-resolution γ-ray spectroscopy. Results: The experimental data are in agreement with previous measurements at higher energies. Since the cross-section prediction of the Ce142(γ,n) reaction is exclusively sensitive to the γ-ray strength function, the resulting cross-section values were compared to Hauser-Feshbach calculations using different γ-ray strength functions. A microscopic description within the framework of the Hartree-Fock-BCS model describes the experimental values well within the measured energy range. Conclusions: The measured data show that the predicted (γ,n) reaction rate is correct within a factor of 2 even though the closed neutron shell N =82 is approached. This agreement allows us to constrain the (n,γ) cross section and to improve the understanding of the s-process branching at Ce141.

  2. Influence of fentanyl and morphine on intestinal circulation

    Energy Technology Data Exchange (ETDEWEB)

    Tverskoy, M.; Gelman, S.; Fowler, K.C.; Bradley, E.L.

    1985-06-01

    The influence of fentanyl and morphine on the intestinal circulation was evaluated in an isolated loop preparation in 37 dogs anesthetized with pentobarbital intravenously. Selected intestinal segments were pumped with aortic blood at a constant pressure of 100 mm Hg. A mixture of /sup 86/Rb and 9-micron spheres labeled with /sup 141/Ce was injected into the arterial cannula supplying the intestinal loop, while mesenteric venous blood was collected for activity counting. A strong correlation was found between the clearances of rubidium and microspheres (r = 0.97, P less than 0.0001), suggesting that the shunting of 9-micron spheres through the intestines reflects the shunting of blood through nonnutritive vessels. Intravenous fentanyl decreased oxygen uptake (O/sub 2/up), and vascular resistance (VR), and increased blood flow (BF), rubidium and microsphere clearances (Cl-Rb, Cl-Sph, respectively), and permeability--surface area product (PS) in a dose-related fashion. Intravenous morphine in a dose of 1 mg X kg-1 increased Cl-Rb (nutritive BF) without changes in total (nutritive and nonnutritive) BF. This increase in nutritive BF is probably related to morphine-induced histamine release. Morphine in a dose of 5 mg X kg-1 was accompanied by vasoconstriction that was completely abolished by alpha-adrenoceptor blockade. The data suggest that morphine-induced intestinal vasoconstriction is mediated via a release of epinephrine, apparently from the adrenal medulla. It is concluded that changes in the intestinal circulation during anesthesia with narcotics might play a certain role in the cardiovascular homeostasis during anesthesia and surgery. An increase in oxygen content in portal venous blood, resulting from a decrease in intestinal oxygen uptake, should facilitate hepatic oxygenation.

  3. The measurement of radioactive microspheres in biological samples

    International Nuclear Information System (INIS)

    Measurements of the distribution of radioactive microspheres are used in investigations of regional coronary blood flow, but the size and shape of the heart varies for different test animals, and the organ is frequently divided into smaller pieces for studies of regional perfusion. Errors are introduced by variations in the distribution of the radioactive source and the amount of Compton scatter in different samples. A technique has therefore been developed to allow the counting of these tissue samples in their original form, and correction factors have been derived to inter-relate the various counting geometries thus encountered. Dogs were injected with microspheres labelled with 141Ce, 51Cr or 85Sr. The tissue samples did not require remodelling to fit a standard container, and allowance was made for the inhomogeneous distribution in the blood samples. The activities in the centrifuged blood samples were correlated with those from the tissue samples by a calibration procedure involving comparisons of the counts from samples of microspheres embedded in sachets of gelatine, and similar samples mixed with blood and then centrifuged. The calibration data have indicated that 51Cr behaves anomalously, and its use as a label for microspheres may introduce unwarranted errors. A plane cylindrical 10 x 20 cm NaI detector was used, and a 'worst case' correction of 20% was found to be necessary for geometry effects. The accuracy of this method of correlating different geometries was tested by remodelling the same tissue sample into different sizes and comparing the results, and the validity of the technique was supported by agreement of the final results with previously published data. (U.K.)

  4. Experimental Fission Gas Release Determination at High Burnup by Means of Gamma Measurements on Fuel Rods in OL2

    International Nuclear Information System (INIS)

    This article presents the results from the gamma measurements performed on a selection of fuel rods from two SVEA-96 Optima fuel assemblies in Olkiluoto unit 2 (OL2) during February 2008. The measurements were funded by Teollisuuden Voima Oyj (TVO) and carried out by Westinghouse Electric Sweden AB (WSE). The goal of the measurements was to obtain plant specific fission gas release data from OL2 which will later be used to support TVO's burnup increase. The measurements were performed by means of detecting and recording information on gamma rays emanating from radioactive fission products within the fuel rods. A fuel assembly under operation in the reactor will be subject to fission gas release, meaning that gaseous fission products in the fuel matrix will leak out into the fuel rod free volumes, including the upper fuel rod plenum. The magnitude of fission gas release is closely related to the operation conditions, such as burnup and the pellet power/temperature history. Fission gas which is released into the plenum leads to an increased pressure within the fuel rod. Since the gas plenum is a volume free of fuel pellets, radioactive gases present here are therefore relatively easy to measure. A suitable gaseous radioactive fission product is 85Kr which has a gamma energy of 514 keV, and a half life of 10.8 years. Measuring the amount of 85Kr can then be used to quantify the amount of fission gases release during operation. Other sources of gamma rays in the plenum with similar energies are the β+-emitting 58Co and the 106Ru. The half lives of 58Co and 106Ru are 71 days and 372 days, respectively, with corresponding gamma ray energies of 511 keV and 512 keV, respectively. In total, three different gamma rays with similar energies must be resolved by the detector system. In order to perform the measurements, 58Co must have decayed to an extent that allows the 514 keV line to be resolved from the 511 keV positron annihilation gamma ray. The 106Ru is, on the other

  5. Irradiated-Microsphere Gamma Analyzer (IMGA): an integrated system for HTGR coated particle fuel performance assessment

    Energy Technology Data Exchange (ETDEWEB)

    Kania, M.J.; Valentine, K.H.

    1980-02-01

    The Irradiated-Microsphere Gamma Analyzer (IMGA) System, designed and built at ORNL, provides the capability of making statistically accurate failure fraction measurements on irradiated HTGR coated particle fuel. The IMGA records the gamma-ray energy spectra from fuel particles and performs quantitative analyses on these spectra; then, using chemical and physical properties of the gamma emitters it makes a failed-nonfailed decision concerning the ability of the coatings to retain fission products. Actual retention characteristics for the coatings are determined by measuring activity ratios for certain gamma emitters such as /sup 137/Cs//sup 95/Zr and /sup 144/Ce//sup 95/Zr for metallic fission product retention and /sup 134/Cs//sup 137/Cs for an indirect measure of gaseous fission product retention. Data from IMGA (which can be put in the form of n failures observed in N examinations) can be accurately described by the binomial probability distribution model. Using this model, a mathematical relationship between IMGA data (n,N), failure fraction, and confidence level was developed. To determine failure fractions of less than or equal to 1% at confidence levels near 95%, this model dictates that from several hundred to several thousand particles must be examined. The automated particle handler of the IMGA system provides this capability. As a demonstration of failure fraction determination, fuel rod C-3-1 from the OF-2 irradiation capsule was analyzed and failure fraction statistics were applied. Results showed that at the 1% failure fraction level, with a 95% confidence level, the fissile particle batch could not meet requirements; however, the fertile particle exceeded these requirements for the given irradiation temperature and burnup.

  6. RESULTS FOR THE SECOND QUARTER 2010 TANK 50 WAC SLURRY SAMPLE: CHEMICAL AND RADIONUCLIDE CONTAMINANT RESULTS

    Energy Technology Data Exchange (ETDEWEB)

    Reigel, M.; Bibler, N.

    2010-08-04

    This report details the chemical and radionuclide contaminant results for the characterization of the 2010 Second Quarter sampling of Tank 50 for the Saltstone Waste Acceptance Criteria (WAC).1 Information from this characterization will be used by Liquid Waste Operations (LWO) to support the transfer of low-level aqueous waste from Tank 50 to the Salt Feed Tank in the Saltstone Facility in Z-Area, where the waste will be immobilized. This information is also used to update the Tank 50 Waste Characterization System. The following conclusions are drawn from the analytical results provided in this report: (1) The concentrations of the reported chemical and radioactive contaminants were less than their respective WAC targets or limits unless noted in this section. (2) The reported detection limits for {sup 94}Nb and {sup 144}Ce are above both the established and requested limits from References 4 and 6. (3) The reported detection limits for {sup 247}Cm and {sup 249}Cf are above the requested limits from Reference 4. However, they are below the limits established in Reference 6. (4) The reported detection limit for Isopar L is greater than the limit from Table 3 of the WAC. (5) A measurable concentration of Norpar 13 is present in the sample. The reported concentration is greater than the requested limit from Table 4 and Attachment 8.2 of the WAC. (6) Isopar L and Norpar 13 have limited solubility in aqueous solutions making it difficult to obtain consistent and reliable sub-samples. The values reported in this memo are the concentrations in the sub-sample as detected by the GC/MS; however, the results may not accurately represent the concentrations of the analytes in Tank 50. (7) The detection limit for isopropanol has been lowered from 0.5 mg/L to 0.25 mg/L{sup 7}. This revised limit now satisfies the limit in Table 4 of the WAC.

  7. Dose assessment for the Metlino and Muslyumovo populations who lived along the Techa river from 1949 to 1954.

    Science.gov (United States)

    Mokrov, Yuri G

    2004-09-01

    In the period from 1949 to 1956, liquid radioactive waste was routinely and accidentally discharged by the Mayak Production Association, Southern Urals, Russia, into the Techa river. Based on a novel approach, the contamination of the Techa river water, the bottom sediments and the adjacent flood plains was modelled, and internal and external doses were estimated for two villages located downstream of the site of liquid radioactive waste release. Altogether, 11 radionuclides that occurred in the liquid radioactive waste were included in the calculations. The results suggest significantly higher doses than previously assumed, with the major contribution in the year 1951. Radionuclides with half-lives of less than 1 year, such as 89Sr, 131I, 95Zr+95Nb, 103Ru+103mRh, 140Ba+140La, and 144Ce+144Pr, represent the major sources and, in contrast, long-lived radionuclides, such as 90Sr and 137Cs that have so far been assumed to be most important, did not dominate the doses. For adults from the village Metlino, located 7 km downstream of the site of liquid radioactive waste discharge, the committed effective doses due to intake of radionuclides were calculated to be about 2.3 Sv, while the external doses were between about 1.2 Sv and 6.9 Sv. On the other hand, for adults from Muslyumovo, located 75 km downstream, the committed effective doses due to intake of radionuclides were calculated to be about 0.5 Sv, while the external doses were between 0.5 Sv and 2.0 Sv. The values for the skin doses to the Metlino and Muslyumovo populations were about 7.1 Sv and 1.3 Sv, respectively. It is concluded that the current dose estimates for the residents of the Techa river need, therefore, reevaluation. PMID:15378312

  8. Lichen (sp. Cladonia) as a deposition indicator for transuranium elements investigated with the Chernobyl fallout

    Energy Technology Data Exchange (ETDEWEB)

    Paatero, Jussi; Jaakkola, Timo; Kulmala, Seija [Helsinki Univ., Radiochemistry Lab., Helsinki (Finland)

    1998-06-01

    The feasibility of employing carpet-forming lichens (sp. Cladonia) as a measure for the deposition of transuranium elements was investigated with the Chernobyl fallout. In Finland, the deposition of these elements after the accident was very uneven. The highest deposition values for {sup 238}Pu, {sup 239,240}Pu, {sup 241}Am, {sup 242}Cm and {sup 243,244}Cm were 5.7, 3.0, 1.3, 98 and 0.025 Bq m{sup -2}, respectively. The amount of deposited {sup 239,240}Pu was, however, only some percent of the fallout of the nuclear test explosions of the 1950s and the 1960s. Instead, practically no {sup 242}Cm was released into the environment during the weapons` testing. The correlation between the refractory nuclides {sup 238}Pu, {sup 239,240}Pu, {sup 241}Am, {sup 242}Cm, {sup 95}Zr and {sup 144}Ce in lichen was high (r = 0.709-0.979), but the correlation between the transuranium elements and volatile {sup 137}Cs was much lower (r = 0.227-0.276). The calculated biological half-lives of Pu and Am in lichen were 730 and 320 days, respectively. The {sup 238}Pu/{sup 239,240}Pu activity ratio in the top parts of lichen samples was 0.54 ``+`` 0.02 corresponding to a burn-up value of 12 MWd kg{sup -1}. The {sup 238}Pu/{sup 239,240}Pu activity ratios of 0.43 and 0.69 measured from two isolated hot particles correspond to burn-up values of 10 and 14 MWd kg{sup -1}, respectively. (author).

  9. Lovelace ITRI studies on the toxicity of inhaled radionuclides in beagle dogs

    International Nuclear Information System (INIS)

    This paper reviews 19 studies conducted by the Lovelace ITRI on the toxicity of inhaled radionuclides in beagle dogs. These studies provide information to estimate potential health effects in accidentally exposed people. Specific radionuclides (90Sr, 90Y, 91Y, 137Cs, 144Ce, 238Pu, and 239Pu), chemical forms, and particle sizes were selected for study because they are abundant in nuclear operations and deliver a wide range of radiation dose patterns. Depending upon the aerosol, one or more of the following organs or tissues received the significant irradiation: lung, nasal cavity, lung-associated lymph nodes, whole body, liver, or skeleton, with the radiation dose delivered over durations of time ranging from a few days to several years. In eight studies monodisperse particles of either 238PuO2 or 239PuO2 were used to evaluate the influence of particle number and total dose on lung cancer induction. Most studies involved single, brief exposures of young adult dogs, but two studies used immature dogs, two used aged dogs, and two studies involved repeated brief exposures. For each aerosol two types of studies were conducted. One was used to evaluate the time course of retention of radioactivity in various tissues of the body for calculating radiation doses. The second was used to determine health effects in animals exposed to achieve different initial lung burdens and observed for the remainder of their life spans. Initial lung burdens were selected to produce early morbidity and mortality at the highest levels and an excess of late-occurring diseases such as cancer at the lowest levels. The latter dogs have had an excess incidence of cancer, especially of the lung, lung-associated lymph nodes, nasal cavity, skeleton, and liver. Relationships between radiation doses to various tissues and effects have been evaluated for individual studies

  10. Feasibility study of passive gamma spectrometry of molten core material from Fukushima Daiichi Nuclear Power Station unit 1, 2, and 3 cores for special nuclear material accountancy - low-volatile FP and special nuclear material inventory analysis and fundamental characteristics of gamma-rays from fuel debris

    International Nuclear Information System (INIS)

    The technologies applied to the analysis of the Three Mile Island accident were examined in a feasibility study of gamma spectrometry of molten core material from the Fukushima Daiichi Nuclear Power Station unit 1, 2, and 3 cores for special nuclear material accountancy. The focus is on low-volatile fission products and heavy metal inventory analysis, and the fundamental characteristics of gamma-rays from fuel debris with respect to passive measurements. The inventory ratios of the low-volatile lanthanides, 154Eu and 144Ce, to special nuclear materials were evaluated by the entire core inventories in units 1, 2, and 3 with an estimated uncertainty of 9%-13% at the 1σ level for homogenized molten fuel material. The uncertainty is expected to be larger locally owing to the use of the irradiation cycle averaging approach. The ratios were also evaluated as a function of burnup for specific fuel debris with an estimated uncertainty of 13%-25% at the 1σ level for units 1 and 2, and most of the fuels in unit 3, although the uncertainty regarding the separated mixed oxide fuel in unit 3 would be significantly higher owing to the burnup dependence approach. Source photon spectra were also examined and cooling-time-dependent data sets were prepared. The fundamental characteristics of high-energy gamma-rays from fuel debris were investigated by a bare-sphere model transport calculation. Mass attenuation coefficients of fuel debris were evaluated to be insensitive to its possible composition in a high-energy region. The leakage photon ratio was evaluated using a variety of parameters, and a significant impact was confirmed for a certain size of fuel debris. Its correlation was summarized with respect to the leakage photopeak ratio of source 154Eu. Finally, a preliminary study using a hypothetical canister model of fuel debris based on the experience at Three Mile Island was presented, and future plans were introduced. (author)

  11. Destructive radiochemical analysis of uraniumsilicide fuel for burnup determination

    Energy Technology Data Exchange (ETDEWEB)

    Gysemans, M.; Bocxstaele, M. van; Bree, P. van; Vandevelde, L.; Koonen, E.; Sannen, L. [SCK-CEN, Boeretang, Mol (Belgium); Guigon, B. [CEA, Centre de Cadarache, Saint Paul lez Durance (France)

    2004-07-01

    During the design phase of the French research reactor Jules Horowitz (RJH) several types of low enriched uranium fuels (LEU), i.e. <20% {sup 235}U enrichment, are studied as possible candidate fuel elements for the reactor core. One of the LEU fuels that is taken into consideration is an uraniumsilicide based fuel with U{sub 3}Si{sub 2} dispersed in an aluminium matrix. The development and evaluation of such a new fuel for a research reactor requires an extensive testing and qualification program, which includes destructive radiochemical analysis to determine the burnup of irradiated fuel with a high accuracy. In radiochemistry burnup is expressed as atom percent burnup and is a measure for the number of fissions that have occurred per initial 100 heavy element atoms (%FIMA). It is determined by measuring the number of heavy element atoms in the fuel and the number of atoms of selected key fission products that are proportional to the number of fissions that occurred during irradiation. From the few fission products that are suitable as fission product monitor, the stable Nd-isotopes {sup 143}Nd, {sup 144}Nd, {sup 145}Nd, {sup 146}Nd, {sup 148Nd}, {sup 150}Nd and the gamma-emitters {sup 137}Cs and {sup 144}Ce are selected for analysis. Samples form two curved U{sub 3}Si{sub 2} plates, with a fuel core density of 5.1 and 6.1 g U/cm{sup 3} (35% {sup 235}U) and being irradiated in the BR2 reactor of SCK x CEN{sup [1]}, were analyzed. (orig.)

  12. Ruthenium release modelling in air under severe accident conditions using the MAAP4 code

    Energy Technology Data Exchange (ETDEWEB)

    Beuzet, E.; Lamy, J.S. [EDF R and D, 1 avenue du General de Gaulle, F-92140 Clamart (France); Perron, H. [EDF R and D, Avenue des Renardieres, Ecuelles, F-77818 Moret sur Loing (France); Simoni, E. [Institut de Physique Nucleaire, Universite de Paris Sud XI, F-91406 Orsay (France)

    2010-07-01

    In a nuclear power plant (NPP), in some situations of low probability of severe accidents, an air ingress into the vessel occurs. Air is a highly oxidizing atmosphere that can lead to an enhanced core degradation affecting the release of Fission Products (FPs) to the environment (source term). Indeed, Zircaloy-4 cladding oxidation by air yields 85% more heat than by steam. Besides, UO{sub 2} can be oxidised to UO{sub 2+x} and mixed with Zr, which may lead to a decrease of the fuel melting temperature. Finally, air atmosphere can enhance the FPs release, noticeably that of ruthenium. Ruthenium is of particular interest for two main reasons: first, its high radiotoxicity due to its short and long half-life isotopes ({sup 103}Ru and {sup 106}Ru respectively) and second, its ability to form highly volatile compounds such as ruthenium gaseous tetra-oxide (RuO{sub 4}). Considering that the oxygen affinity decreases between cladding, fuel and ruthenium inclusions, it is of great need to understand the phenomena governing fuel oxidation by air and ruthenium release as prerequisites for the source term issues. A review of existing data on ruthenium release, controlled by fuel oxidation, leads us to implement a new model in the EDF version of MAAP4 severe accident code (Modular Accident Analysis Program). This model takes into account the fuel stoichiometric deviation and the oxygen partial pressure evolution inside the fuel to simulate its oxidation by air. Ruthenium is then oxidised. Its oxides are released by volatilisation above the fuel. All the different ruthenium oxides formed and released are taken into consideration in the model, in terms of their particular reaction constants. In this way, partial pressures of ruthenium oxides are given in the atmosphere so that it is possible to know the fraction of ruthenium released in the atmosphere. This new model has been assessed against an analytical test of FPs release in air atmosphere performed at CEA (VERCORS RT8). The

  13. Analysis of Radionuclide Migration Through a 200-m Vadose Zone Following a 16-Year Infiltration Event

    Energy Technology Data Exchange (ETDEWEB)

    Tompson, A F B; Smith, D K; Hudson, G B

    2002-01-31

    The CAMBRIC nuclear test was conducted beneath Frenchman Flat at the Nevada Test Site on May 14, 1965. The nuclear device was emplaced in heterogeneous alluvium, approximately 70 m beneath the ambient water table, which is itself 220 m beneath the ground surface. Approximately 10 years later, groundwater adjacent to the test was pumped steadily for 16 years to elicit information on radionuclide migration in the saturated zone. The pumping well effluent--containing mostly soluble radionuclides such as tritium, {sup 14}C, {sup 36}Cl, {sup 85}Kr, {sup 129}I, and {sup 106}Ru--was monitored, discharged to an unlined ditch, and allowed to flow towards Frenchman Lake just over one kilometer away. Water discharged into the ditch infiltrated into the ground during flow along the ditch. This created an unexpected and remarkable second experiment in which the migration of the effluent through the 220 meters of unsaturated media, or ''vadose zone'', back to the water table, could be studied. In this paper, the pumping and effluent data are being utilized in conjunction with a series of geologic data, new radionuclide measurements, isotopic age-dating estimates, and vadose zone flow and transport models to better understand the movement of radionuclides between the ditch and the water table. Measurements of radionuclide concentrations in water samples produced from a water table monitoring well 100m away from the ditch indicate rising levels of tritium since 1993. The detection of tritium in the monitoring well occurs approximately 16 years after its initial discharge into the ditch. Modeling and tritium age dating have suggested 3 to 5 years of this 16-year transit time occurred solely in the vadose zone. They also suggest considerable recirculation of the pumping well discharge back into the original pumping well. Surprisingly, no {sup 14}C was observed at the water table, suggesting its preferential retention, possibly due to precipitation or other

  14. Inorganic, radioisotopic and organic analysis of 241-AP-101 tank waste

    International Nuclear Information System (INIS)

    Battelle received five samples from Hanford waste tank 241-AP-101, taken at five different depths within the tank. No visible solids or organic layer were observed in the individual samples. Individual sample densities were measured, then the five samples were mixed together to provide a single composite. The composite was homogenized and representative sub-samples taken for inorganic, radioisotopic, and organic analysis. All analyses were performed on triplicate sub-samples of the composite material. The sample composite did not contain visible solids or an organic layer. A subsample held at 10 C for seven days formed no visible solids. The characterization of the 241-AP-101 composite samples included: (1) Inductively-coupled plasma spectrometry for Ag, Al, Ba, Bi, Ca, Cd, Cr, Cu, Fe, K, La, Mg, Mn, Na, Nd, Ni, P, Pb, Pd, Ru, Rh, Si, Sr, Ti, U, Zn, and Zr (Note: Although not specified in the test plan, As, B, Be, Co, Li, Mo, Sb, Se, Sn, Tl, V, W, and Y were also measured and reported for information only) (2) Radioisotopic analyses for total alpha and total beta activities, 3H, 14C, 60Co, 79Se, 90Sr, 99Tc as pertechnetate, 106Ru/Rh, 125Sb, 134Cs, 137Cs, 152Eu, 154Eu, 155Eu, 238Pu, 239+240Pu, 241Am, 242Cm, and 243+244Cm; (3) Inductively-coupled plasma mass spectrometry for 237Np, 239Pu, 240Pu, 99Tc, 126Sn, 129I, 231Pa, 233U, 234U, 235U, 236U, 238U, 241AMU, 242AMU, 243AMU, As, B, Be, Ce, Co, Cs, Eu, I, Li, Mo, Pr, Rb, Sb, Se, Ta, Te, Th, Tl, V, and W; (4) total U by kinetic phosphorescence analysis; (5) Ion chromatography for Cl, F, NO2, NO3, PO4, SO4, acetate, formate, oxalate, and citrate; (6) Density, inorganic carbon and organic carbon by two different methods, mercury, free hydroxide, ammonia, and cyanide. The 241-AP-101 composite met all contract limits (molar ratio of analyte to sodium or ratio of becquerels of analyte to moles of sodium) defined in Specification 7 for Envelope A. Except for a few cases, the characterization results met or surpassed the

  15. IMITATION OF STANDARD VOLUMETRIC ACTIVITY METAL SAMPLES

    Directory of Open Access Journals (Sweden)

    A. I. Zhukouski

    2016-01-01

    Full Text Available Due to the specific character of problems in the field of ionizing radiation spectroscopy, the R&D and making process of standard volumetric activity metal samples (standard samples for calibration and verification of spectrometric equipment is not only expensive, but also requires the use of highly qualified experts and a unique specific equipment. Theoretical and experimental studies performed have shown the possibility to use imitators as a set of alternating point sources of gamma radiation and metal plates and their use along with standard volumetric activity metal samples for calibration of scintillation-based detectors used in radiation control in metallurgy. Response functions or instrumental spectra of such spectrometer to radionuclides like 137Cs, 134Cs, 152Eu, 154Eu, 60Co, 54Mn, 232Th, 226Ra, 65Zn, 125Sb+125mTe, 106Ru+106Rh, 94Nb, 110mAg, 233U, 234U, 235U and 238U are required for calibration in a given measurement geometry. Standard samples in the form of a probe made of melt metal of a certain diameter and height are used in such measurements. However, the production of reference materials is costly and even problematic for such radionuclides as 94Nb, 125Sb+125mTe, 234U, 235U  etc. A recognized solution to solve this problem is to use the Monte-Carlo simulation method. Instrumental experimental and theoretical spectra obtained by using standard samples and their imitators show a high compliance between experimental spectra of real samples and the theoretical ones of their Monte-Carlo models, between spectra of real samples and the ones of their imitators and finally, between experimental spectra of real sample imitators and the theoretical ones of their Monte-Carlo models. They also have shown the adequacy and consistency of the approach in using a combination of metal scattering layers and reference point gamma-ray sources instead of standard volumetric activity metal samples. As for using several reference point gamma-ray sources

  16. Results of 1999 Spectral Gamma-Ray and Neutron Moisture Monitoring of Boreholes at Specific Retention Facilities in the 200 East Area, Hanford Site

    Energy Technology Data Exchange (ETDEWEB)

    DG Horton; RR Randall

    2000-01-18

    Twenty-eight wells and boreholes in the 200 East Are% Hanford Site, Washington were monitored in 1999. The monitored facilities were past-practice liquid waste disposal facilities and consisted of six cribs and nineteen ''specific retention'' cribs and trenches. Monitoring consisted of spectral gamma-ray and neutron moisture logging. All data are included in Appendix B. The isotopes {sup 137}Cs, {sup 60}Co, {sup 235}U, {sup 238}U, and {sup 154}Eu were identified on spectral gamma logs from boreholes monitoring the PUREX specific retention facilities; the isotopes {sup 137}Cs, {sup 60}Co, {sup 125}Sb, and {sup 154}Eu were identified on the logs from boreholes at the BC Controlled Area cribs and trenches; and {sup 137}Cs, {sup 60}Co, and {sup 125}Sb were, identified on the logs from boreholes at the BX specific retention trenches. Three boreholes in the BC Controlled Area and one at the BX trenches had previous spectral gamma logs available for comparison with 1999 logs. Two of those logs showed that changes in the subsurface distribution of {sup 137}CS and/or {sup 60}Co had occurred since 1992. Although the changes are not great, they do point to continued movement of contaminants in the vadose zone. The logs obtained in 1999 create a larger baseline for comparison with future logs. Numerous historical gross gamma logs exist from most of the boreholes logged. Qualitative comparison of those logs with the 1999 logs show many substantial changes, most of which reflect the decay of deeper short-lived isotopes, such as {sup 106}Ru and {sup 125}Sb, and the much slower decay of shallower and longer-lived isotopes such as {sup 137}Cs. The radionuclides {sup 137}Cs and {sup 60}Co have moved in two boreholes since 1992. Given the amount of movement and the half-lives of the isotopes, it is expected that they will decay to insignificant amounts before reaching groundwater. However, gamma ray logging cannot detect many of the contaminants of interest such

  17. Problems in shallow land disposal of solid low-level radioactive waste in the united states

    Science.gov (United States)

    Stevens, P.R.; DeBuchananne, G.D.

    1976-01-01

    Disposal of solid low-level wastes containing radionuclides by burial in shallow trenches was initiated during World War II at several sites as a method of protecting personnel from radiation and isolating the radionuclides from the hydrosphere and biosphere. Today, there are 11 principal shallow-land burial sites in the United States that contain a total of more than 1.4 million cubic meters of solid wastes contaminated with a wide variety of radionuclides. Criteria for burial sites have been few and generalized and have contained only minimal hydrogeologic considerations. Waste-management practices have included the burial of small quantities of long-lived radionuclides with large volumes of wastes contaminated with shorter-lived nuclides at the same site, thereby requiring an assurance of extremely long-time containment for the entire disposal site. Studies at 4 of the 11 sites have documented the migration of radionuclides. Other sites are being studied for evidence of containment failure. Conditions at the 4 sites are summarized. In each documented instance of containment failure, ground water has probably been the medium of transport. Migrating radionuclides that have been identified include90Sr,137Cs,106Ru,239Pu,125Sb,60Co, and3H. Shallow land burial of solid wastes containing radionuclides can be a viable practice only if a specific site satisfies adequate hydrogeologic criteria. Suggested hydrogeologic criteria and the types of hydrogeologic data necessary for an adequate evaluation of proposed burial sites are given. It is mandatory that a concomitant inventory and classification be made of the longevity, and the physical and chemical form of the waste nuclides to be buried, in order that the anticipated waste types can be matched to the containment capability of the proposed sites. Ongoing field investigations at existing sites will provide data needed to improve containment at these sites and help develop hydrogeologic criteria for new sites. These

  18. Inorganic, radioisotopic and organic analysis of 241-AP-101 tank waste

    Energy Technology Data Exchange (ETDEWEB)

    SK Fiskum; PR Bredt; JA Campbell; LR Greenwood; OT Farmer; GJ Lumetta; GM Mong; RT Ratner; CZ Soderquist; RG Swoboda; MW Urie; JJ Wagner

    2000-06-28

    Battelle received five samples from Hanford waste tank 241-AP-101, taken at five different depths within the tank. No visible solids or organic layer were observed in the individual samples. Individual sample densities were measured, then the five samples were mixed together to provide a single composite. The composite was homogenized and representative sub-samples taken for inorganic, radioisotopic, and organic analysis. All analyses were performed on triplicate sub-samples of the composite material. The sample composite did not contain visible solids or an organic layer. A subsample held at 10 C for seven days formed no visible solids. The characterization of the 241-AP-101 composite samples included: (1) Inductively-coupled plasma spectrometry for Ag, Al, Ba, Bi, Ca, Cd, Cr, Cu, Fe, K, La, Mg, Mn, Na, Nd, Ni, P, Pb, Pd, Ru, Rh, Si, Sr, Ti, U, Zn, and Zr (Note: Although not specified in the test plan, As, B, Be, Co, Li, Mo, Sb, Se, Sn, Tl, V, W, and Y were also measured and reported for information only) (2) Radioisotopic analyses for total alpha and total beta activities, {sup 3}H, {sup 14}C, {sup 60}Co, {sup 79}Se, {sup 90}Sr, {sup 99}Tc as pertechnetate, {sup 106}Ru/Rh, {sup 125}Sb, {sup 134}Cs, {sup 137}Cs, {sup 152}Eu, {sup 154}Eu, {sup 155}Eu, {sup 238}Pu, {sup 239+240}Pu, {sup 241}Am, {sup 242}Cm, and {sup 243+244}Cm; (3) Inductively-coupled plasma mass spectrometry for {sup 237}Np, {sup 239}Pu, {sup 240}Pu, {sup 99}Tc, {sup 126}Sn, {sup 129}I, {sup 231}Pa, {sup 233}U, {sup 234}U, {sup 235}U, {sup 236}U, {sup 238}U, {sup 241}AMU, {sup 242}AMU, {sup 243}AMU, As, B, Be, Ce, Co, Cs, Eu, I, Li, Mo, Pr, Rb, Sb, Se, Ta, Te, Th, Tl, V, and W; (4) total U by kinetic phosphorescence analysis; (5) Ion chromatography for Cl, F, NO{sub 2}, NO{sub 3}, PO{sub 4}, SO{sub 4}, acetate, formate, oxalate, and citrate; (6) Density, inorganic carbon and organic carbon by two different methods, mercury, free hydroxide, ammonia, and cyanide. The 241-AP-101 composite met all

  19. Environmental radiation measurement in CTBT verification system

    International Nuclear Information System (INIS)

    This paper introduces the technical requirements of the Comprehensive Nuclear-Test-Ban Treaty (CTBT) Radionuclide Stations, the CTBT-related activities carried out by the Japan Atomic Energy Research Institute (JAERI), and the ripple effects of such acquired radionuclide data on general researches. The International Monitoring System (IMS), which is one of the CTBT verification regime. Consists of 80 radionuclide air monitoring stations (of those, 40 stations monitor noble gas as well) and 16 certified laboratories that support these stations throughout the world. For radionuclide air monitoring under the CTBT, the stations collect particulates in the atmosphere on a filter and determine by gamma-ray spectrometry the presence or absence of any radionuclides (e.g. 140Ba, 131I, 99Mo, 132Te, 103Ru, 141Ce, 147Nd, 95Zr, etc.) that offer clear evidence of possible nuclear explosion. Minimum technical requirements are stringently set for the radionuclide air monitoring stations: 500 m3/h air flow rate, 24-hour acquisition time, 10 to 30 Bq/m3 of detection sensitivity for 140Ba, and less than 7 consecutive days, or total of 15 days, a year of shutdown at the stations. For noble gas monitoring, on the other hand, the stations separate Xe from gas elements in the atmosphere and, after purifying and concentrating it, measure 4 nuclides, 131mXe, 133Xe, 133mXe, and 135Xe, by gamma-ray spectrometry or beta-gamma coincidence method. Minimum technical requirements are also set for the noble gas measurement: 0.4 m3/h air flow rate, a full capacity of 10 m3, and 1 Bq/m3 of detection sensitivity for 133Xe, etc. On the request of the Ministry of Education, Culture, Sports and Technology, the JAERI is currently undertaking the establishment of the CTBT radionuclide monitoring stations at both Takasaki (both particle and noble gas) and Okinawa (particle), the certified laboratory at JAERI Tokai, and the National Data Center (NDC 2) at JAERI Tokai, which handles radionuclide data, as

  20. Deposition of Chernobyl-derived transuranium nuclides and short- lived radon-222 progeny in Finland

    International Nuclear Information System (INIS)

    In this study the atmospheric deposition of radionuclides was investigated from two different viewpoints. The Chernobyl nuclear power plant accident in April 1986 caused a widely spread plume of radionuclides, including transuranium elements. The regional deposition of these elements in Finland was assessed based on lichen and peat samples. Unlike the deposition of transuranium elements from the weapons tests in the 1950's and 1960's, the deposition from the Chernobyl accident was very unevenly distributed in Finland. Also, the Chernobyl-derived deposition of 299,240Pu even in the most contaminated regions in Finland was still only some 10 per cent of the global fallout from weapons tests. On the other hand, the measured activity concentrations of 241Pu in the upper parts of lichen samples are comparable to those found in samples comparable during the heaviest weapons-test fallout in the early 1960's. The observed average 241Pu/239,240Pu activity ratio in the upper parts of lichen, 95, can be expected to lead at its maximum in the year 2059 to 241Am/239,240Pu activity ratio of 2.8 in the Chernobyl-derived deposition, exclusive of the 241Am present in the original deposition in 1986. The deposition pattern of transuranium elements observed in this work resembles that of refractory gamma-emitting nuclides such as 95Zr and 141Ce. The sampling area of this investigation does not cover the northern part of Finland. However, the fallout pattern of 95Zr would suggest that the deposition of transuranium nuclides north of the 65th latitude was very low. Biological half-lives of 730 d and 320 d for Pu and Am, respectively, were obtained in lichen in this study. The second part of this work is concerned with the factors affecting the wet deposition efficiency of the natural short-lived radon-222 progeny. This was studied with two methods: using recordings of external gamma radiation in central Finland, and using an automatic precipitation gamma analyser in northern Finland

  1. Expeditious method to determine uranium in the process control samples of chemical plant separating (233)U from thoria irradiated in power reactors.

    Science.gov (United States)

    Kedari, C S; Kharwandikar, B K; Banerjee, K

    2016-11-01

    Analysis of U in the samples containing a significant proportion of (232)U and high concentration of Th is of great concern. Transmutation of Th in the nuclear power reactor produces a notable quantity of (232)U (half life 68.9 years) along with fissile isotope (233)U. The decay series of (232)U is initiated with (228)Th (half life 1.9 year) and it is followed by several short lived α emitting progenies, (224)Ra, (220)Rn, (216)Po, (212)Bi and (212)Po. Even at the smallest contamination of (228)Th in the sample, a very high pulse rate of α emission is obtained, which is to be counted for the radiometric determination of [U]. A commercially available anionic type of extractant Alamine®336 is used to obtain the selective extraction of U from other alpha active elements and fission products present in the sample. Experimental conditions of liquid-liquid extraction (LLE) are optimized for obtaining maximum decontamination and recovery of U in the organic phase. The effect of some interfering ionic impurities in the sample on the process of separation is investigated. Depending on the level of the concentration of U in the samples, spectrophotometry or radiometry methods are adopted for its determination after separation by LLE. Under optimized experimental conditions, i.e. 5.5M HCl in the aqueous phase and 0.27M Alamin®336 in the organic phase, the recovery of U is about 100%, the decontamination factor with respect to Th is >2000 and the extraction of fission products like (90)Sr, (144)Ce and (134,137)Cs is negligible. The detection limit for [U] using α radiometry is 10mg/L, even in presence of >100g/L of Th in the sample. Accuracy and precision for the determination of U is also assessed. Reproducibility of results is within 5%. This method shows very good agreement with the results obtained by mass spectrometry.

  2. Organization of radio-ecological monitoring of the areas of the Russian Federation contaminated due to the accident at the Chernobyl NPP (on example of the Bryansk region)

    Science.gov (United States)

    Linnik, Vitaly; Korobova, Elena; Vakulovsky, Sergey

    2013-04-01

    A severe accident at the Chernobyl NPP on April 26th, 1986 has led to radioactive contamination of many regions of the former USSR, now belonging to the Ukraine, the Republic of Belarus and the Russian Federation. Both natural and arable ecosystems have been subjected to fallout of radioactive isotopes. However both the distribution of radionuclides that define radioecological situation has depended not only on the initial contamination density but also on the landscape geochemical features of the areas controlling biogenic and abiogenic factors of radionuclide migration. To study and monitor peculiarities of migration of the most radioecologically significant radionuclides of Cs-137 and Sr-90 in different natural landscapes the Russian Scientific and Practical Experimental Center of the former State Chernobyl Committee has organized in 1992 a network of experimental plots in the most contaminated western part of the Bryansk region. It included 19 plots 100 m x 100 m in size which characterized 8 meadow and 11 forested catenas in the basin of the Iput' river. Cs-137 contamination level of the plots varied in 1992 from 740 kBq/m2 to 1850 kBq/m2. Although the study site has been located in the remote zone and the contamination was of condensation type the sampling performed at 11 plots registered some refractory radionuclides (144Ce, 154Eu, 238,239,240Pu and 90Sr) that proved the presence of fuel particles in fallout as far as 200 km from the damaged reactors. The sampling and monitoring scheme was organized to determine: the isotopic composition and contamination density of the plots; 2) estimation of radionuclide vertical and lateral migration; 3) evaluation of radionuclide inventories in different soil horizons; 4) calculation of radionuclide transfer in soil-plant system. Radiation measurements included field gamma-spectrometry using collimated gamma spectrometer "Corad" developed in the Kurchatov Institute and laboratory spectrometry the soil and plant samples

  3. Expeditious method to determine uranium in the process control samples of chemical plant separating (233)U from thoria irradiated in power reactors.

    Science.gov (United States)

    Kedari, C S; Kharwandikar, B K; Banerjee, K

    2016-11-01

    Analysis of U in the samples containing a significant proportion of (232)U and high concentration of Th is of great concern. Transmutation of Th in the nuclear power reactor produces a notable quantity of (232)U (half life 68.9 years) along with fissile isotope (233)U. The decay series of (232)U is initiated with (228)Th (half life 1.9 year) and it is followed by several short lived α emitting progenies, (224)Ra, (220)Rn, (216)Po, (212)Bi and (212)Po. Even at the smallest contamination of (228)Th in the sample, a very high pulse rate of α emission is obtained, which is to be counted for the radiometric determination of [U]. A commercially available anionic type of extractant Alamine®336 is used to obtain the selective extraction of U from other alpha active elements and fission products present in the sample. Experimental conditions of liquid-liquid extraction (LLE) are optimized for obtaining maximum decontamination and recovery of U in the organic phase. The effect of some interfering ionic impurities in the sample on the process of separation is investigated. Depending on the level of the concentration of U in the samples, spectrophotometry or radiometry methods are adopted for its determination after separation by LLE. Under optimized experimental conditions, i.e. 5.5M HCl in the aqueous phase and 0.27M Alamin®336 in the organic phase, the recovery of U is about 100%, the decontamination factor with respect to Th is >2000 and the extraction of fission products like (90)Sr, (144)Ce and (134,137)Cs is negligible. The detection limit for [U] using α radiometry is 10mg/L, even in presence of >100g/L of Th in the sample. Accuracy and precision for the determination of U is also assessed. Reproducibility of results is within 5%. This method shows very good agreement with the results obtained by mass spectrometry. PMID:27591623

  4. Nuclear fuel cycle and marine environment. Behavior of the Rhone river effluents in the mediterranean sea and of wastes dumped in the northeast atlantic; Cycle du combustible nucleaire et milieu marin. Devenir des effluents rhodaniens en mediterranee et des dechets immerges en atlantique nord-est

    Energy Technology Data Exchange (ETDEWEB)

    Charmasson, S

    1998-07-01

    Man-made radionuclides released into the marine environment by the installations from the nuclear fuel cycle are used as tracers of various bio-geochemical processes. Several installations belonging to the whole nuclear fuel cycle, except the uranium mining, are set up on the Rhone River Banks. The sea disposal of low and intermediate level radioactive waste has never been authorized in the Mediterranean sea but several sites have been used in the North-East especially in abyssal waters. Radionuclides released by the Rhone river installations are used in order to study the dynamics of the Rhone inputs into the Mediterranean Sea. In the river, freshwater samples reflect quite accurately the discharge composition with a predominance of {sup 106}Ru, a radionuclide mostly released by the spent nuclear fuel reprocessing plant in Marcoule. Conversely, at the Rhone mouth, in the sediment compartment {sup 106}Ru yields to caesium isotopes ({sup 134}Cs and {sup 137}Cs) in importance. As these two isotopes demonstrate very different half-lives (30,2 and 2,1 years respectively), the temporal evolution of their ratio acts as a chronometer enabled to date sediment accumulation near the river mouth. Mean accumulation rates greater than 35 cm y{sup -1} have been determined in the pro-deltaic zone near the Roustan buoys over the period 1983-1991. Accumulation rates decrease rapidly with distance from the mouth and therefore most of the {sup 137}Cs inventory in this part of the Gulf of Lions is limited to the pro-deltaic area. A first study about the part the different {sup 137}Cs sources in the Mediterranean Sea play in this inventory has been carried out. Direct (atmospheric) and indirect (fluviatile) inputs due to fallout from both past nuclear tests and the Chernobyl accident could contribute to this inventory at the highest to 40 % while the industrial releases could contribute at the lowest to 60 %. The last site used for the dumping of low and intermediate level radioactive

  5. Nuclear fuel cycle and marine environment. Behavior of the Rhone river effluents in the mediterranean sea and of wastes dumped in the northeast atlantic; Cycle du combustible nucleaire et milieu marin. Devenir des effluents rhodaniens en mediterranee et des dechets immerges en atlantique nord-est

    Energy Technology Data Exchange (ETDEWEB)

    Charmasson, S

    1998-07-01

    Man-made radionuclides released into the marine environment by the installations from the nuclear fuel cycle are used as tracers of various bio-geochemical processes. Several installations belonging to the whole nuclear fuel cycle, except the uranium mining, are set up on the Rhone River Banks. The sea disposal of low and intermediate level radioactive waste has never been authorized in the Mediterranean sea but several sites have been used in the North-East especially in abyssal waters. Radionuclides released by the Rhone river installations are used in order to study the dynamics of the Rhone inputs into the Mediterranean Sea. In the river, freshwater samples reflect quite accurately the discharge composition with a predominance of {sup 106}Ru, a radionuclide mostly released by the spent nuclear fuel reprocessing plant in Marcoule. Conversely, at the Rhone mouth, in the sediment compartment {sup 106}Ru yields to caesium isotopes ({sup 134}Cs and {sup 137}Cs) in importance. As these two isotopes demonstrate very different half-lives (30,2 and 2,1 years respectively), the temporal evolution of their ratio acts as a chronometer enabled to date sediment accumulation near the river mouth. Mean accumulation rates greater than 35 cm y{sup -1} have been determined in the pro-deltaic zone near the Roustan buoys over the period 1983-1991. Accumulation rates decrease rapidly with distance from the mouth and therefore most of the {sup 137}Cs inventory in this part of the Gulf of Lions is limited to the pro-deltaic area. A first study about the part the different {sup 137}Cs sources in the Mediterranean Sea play in this inventory has been carried out. Direct (atmospheric) and indirect (fluviatile) inputs due to fallout from both past nuclear tests and the Chernobyl accident could contribute to this inventory at the highest to 40 % while the industrial releases could contribute at the lowest to 60 %. The last site used for the dumping of low and intermediate level radioactive

  6. Nuclear fuel cycle and marine environment. Behavior of the Rhone river effluents in the mediterranean sea and of wastes dumped in the northeast atlantic

    International Nuclear Information System (INIS)

    Man-made radionuclides released into the marine environment by the installations from the nuclear fuel cycle are used as tracers of various bio-geochemical processes. Several installations belonging to the whole nuclear fuel cycle, except the uranium mining, are set up on the Rhone River Banks. The sea disposal of low and intermediate level radioactive waste has never been authorized in the Mediterranean sea but several sites have been used in the North-East especially in abyssal waters. Radionuclides released by the Rhone river installations are used in order to study the dynamics of the Rhone inputs into the Mediterranean Sea. In the river, freshwater samples reflect quite accurately the discharge composition with a predominance of 106Ru, a radionuclide mostly released by the spent nuclear fuel reprocessing plant in Marcoule. Conversely, at the Rhone mouth, in the sediment compartment 106Ru yields to caesium isotopes (134Cs and 137Cs) in importance. As these two isotopes demonstrate very different half-lives (30,2 and 2,1 years respectively), the temporal evolution of their ratio acts as a chronometer enabled to date sediment accumulation near the river mouth. Mean accumulation rates greater than 35 cm y-1 have been determined in the pro-deltaic zone near the Roustan buoys over the period 1983-1991. Accumulation rates decrease rapidly with distance from the mouth and therefore most of the 137Cs inventory in this part of the Gulf of Lions is limited to the pro-deltaic area. A first study about the part the different 137Cs sources in the Mediterranean Sea play in this inventory has been carried out. Direct (atmospheric) and indirect (fluviatile) inputs due to fallout from both past nuclear tests and the Chernobyl accident could contribute to this inventory at the highest to 40 % while the industrial releases could contribute at the lowest to 60 %. The last site used for the dumping of low and intermediate level radioactive waste in the North-East Atlantic has been

  7. Ruthenium release modelling in air and steam atmospheres under severe accident conditions using the MAAP4 code

    International Nuclear Information System (INIS)

    Highlights: ► We developed a new modelling of fuel oxidation and ruthenium release in the EDF version of the MAAP4 code. ► We validated this model against some VERCORS experiments. ► Ruthenium release prediction quantitatively and qualitatively well reproduced under air and steam atmospheres. - Abstract: In a nuclear power plant (NPP), a severe accident is a low probability sequence that can lead to core fusion and fission product (FP) release to the environment (source term). For instance during a loss-of-coolant accident, water vaporization and core uncovery can occur due to decay heat. These phenomena enhance core degradation and, subsequently, molten materials can relocate to the lower head of the vessel. Heat exchange between the debris and the vessel may cause its rupture and air ingress. After lower head failure, steam and air entering in the vessel can lead to degradation and oxidation of materials that are still intact in the core. Indeed, Zircaloy-4 cladding oxidation is very exothermic and fuel interaction with the cladding material can decrease its melting temperature by several hundred of Kelvin. FP release can thus be increased, noticeably that of ruthenium under oxidizing conditions. Ruthenium is of particular interest because of its high radio-toxicity due to 103Ru and 106Ru isotopes and its ability to form highly volatile compounds, even at room temperature, such as gaseous ruthenium tetra-oxide (RuO4). It is consequently of great need to understand phenomena governing steam and air oxidation of the fuel and ruthenium release as prerequisites for the source term issues. A review of existing data on these phenomena shows relatively good understanding. In terms of oxygen affinity, the fuel is oxidized before ruthenium, from UO2 to UO2+x. Its oxidation is a rate-controlling surface exchange reaction with the atmosphere, so that the stoichiometric deviation and oxygen partial pressure increase. High temperatures combined with the presence of

  8. Natural and anthropogenic radionuclides in Brazilian commercial dog food: preliminary results

    Energy Technology Data Exchange (ETDEWEB)

    Cavalcante, Fernanda; Pecequilo, Brigitte R.S. [Instituto de Pesquisas Energeticas e Nucleares - IPEN, Av. Professor Lineu Prestes 2242, 05508-000 Sao Paulo (Brazil)

    2014-07-01

    spigot. These samples, after resting for 30 days to ensure secular equilibrium, were placed in an extended range high-purity germanium detector with 40% relative efficiency, and the acquired spectra are analyzed using the InterWinner 6.0 software. The results have shown no concentrations of artificial radionuclides, such as Cs-137, Co-60, Ru-106, Ru-103, I-131 and Am-241, whilst the concentrations of natural radionuclides varied from 1.17 ± 0.31 up to 5.01 ± 0.38 Bq/kg for Ra-226; from 1.20 ± 0.50 up to 8.07 ± 0.96 for Th-232 and from 212.90 ± 10.80 up to 377.00 ± 17.78 for K-40. Further, the study will be extended to a larger number of dog food brands and also to cat food brands available in Brazil and eventual radiological consequences of absorbed dose will be assessed. (authors)

  9. Saltstone Vault Classification Samples Modular Caustic Side Solvent Extraction Unit/Actinide Removal Process Waste Stream April 2011

    International Nuclear Information System (INIS)

    Savannah River National Laboratory (SRNL) was asked to prepare saltstone from samples of Tank 50H obtained by SRNL on April 5, 2011 (Tank 50H sampling occurred on April 4, 2011) during 2QCY11 to determine the non-hazardous nature of the grout and for additional vault classification analyses. The samples were cured and shipped to Babcock and Wilcox Technical Services Group-Radioisotope and Analytical Chemistry Laboratory (B and W TSG-RACL) to perform the Toxic Characteristic Leaching Procedure (TCLP) and subsequent extract analysis on saltstone samples for the analytes required for the quarterly analysis saltstone sample. In addition to the eight toxic metals - arsenic, barium, cadmium, chromium, mercury, lead, selenium and silver - analytes included the underlying hazardous constituents (UHC) antimony, beryllium, nickel, and thallium which could not be eliminated from analysis by process knowledge. Additional inorganic species determined by B and W TSG-RACL include aluminum, boron, chloride, cobalt, copper, fluoride, iron, lithium, manganese, molybdenum, nitrate/nitrite as Nitrogen, strontium, sulfate, uranium, and zinc and the following radionuclides: gross alpha, gross beta/gamma, 3H, 60Co, 90Sr, 99Tc, 106Ru, 106Rh, 125Sb, 137Cs, 137mBa, 154Eu, 238Pu, 239/240Pu, 241Pu, 241Am, 242Cm, and 243/244Cm. B and W TSG-RACL provided subsamples to GEL Laboratories, LLC for analysis for the VOCs benzene, toluene, and 1-butanol. GEL also determines phenol (total) and the following radionuclides: 147Pm, 226Ra and 228Ra. Preparation of the 2QCY11 saltstone samples for the quarterly analysis and for vault classification purposes and the subsequent TCLP analyses of these samples showed that: (1) The saltstone waste form disposed of in the Saltstone Disposal Facility in 2QCY11 was not characteristically hazardous for toxicity. (2) The concentrations of the eight RCRA metals and UHCs identified as possible in the saltstone waste form were present at levels below the UTS. (3) Most

  10. SALTSTONE VAULT CLASSIFICATION SAMPLES MODULAR CAUSTIC SIDE SOLVENT EXTRACTION UNIT/ACTINIDE REMOVAL PROCESS WASTE STREAM APRIL 2011

    Energy Technology Data Exchange (ETDEWEB)

    Eibling, R.

    2011-09-28

    Savannah River National Laboratory (SRNL) was asked to prepare saltstone from samples of Tank 50H obtained by SRNL on April 5, 2011 (Tank 50H sampling occurred on April 4, 2011) during 2QCY11 to determine the non-hazardous nature of the grout and for additional vault classification analyses. The samples were cured and shipped to Babcock & Wilcox Technical Services Group-Radioisotope and Analytical Chemistry Laboratory (B&W TSG-RACL) to perform the Toxic Characteristic Leaching Procedure (TCLP) and subsequent extract analysis on saltstone samples for the analytes required for the quarterly analysis saltstone sample. In addition to the eight toxic metals - arsenic, barium, cadmium, chromium, mercury, lead, selenium and silver - analytes included the underlying hazardous constituents (UHC) antimony, beryllium, nickel, and thallium which could not be eliminated from analysis by process knowledge. Additional inorganic species determined by B&W TSG-RACL include aluminum, boron, chloride, cobalt, copper, fluoride, iron, lithium, manganese, molybdenum, nitrate/nitrite as Nitrogen, strontium, sulfate, uranium, and zinc and the following radionuclides: gross alpha, gross beta/gamma, 3H, 60Co, 90Sr, 99Tc, 106Ru, 106Rh, 125Sb, 137Cs, 137mBa, 154Eu, 238Pu, 239/240Pu, 241Pu, 241Am, 242Cm, and 243/244Cm. B&W TSG-RACL provided subsamples to GEL Laboratories, LLC for analysis for the VOCs benzene, toluene, and 1-butanol. GEL also determines phenol (total) and the following radionuclides: 147Pm, 226Ra and 228Ra. Preparation of the 2QCY11 saltstone samples for the quarterly analysis and for vault classification purposes and the subsequent TCLP analyses of these samples showed that: (1) The saltstone waste form disposed of in the Saltstone Disposal Facility in 2QCY11 was not characteristically hazardous for toxicity. (2) The concentrations of the eight RCRA metals and UHCs identified as possible in the saltstone waste form were present at levels below the UTS. (3) Most of the

  11. Natural and anthropogenic radionuclides in Brazilian commercial dog food: preliminary results

    International Nuclear Information System (INIS)

    spigot. These samples, after resting for 30 days to ensure secular equilibrium, were placed in an extended range high-purity germanium detector with 40% relative efficiency, and the acquired spectra are analyzed using the InterWinner 6.0 software. The results have shown no concentrations of artificial radionuclides, such as Cs-137, Co-60, Ru-106, Ru-103, I-131 and Am-241, whilst the concentrations of natural radionuclides varied from 1.17 ± 0.31 up to 5.01 ± 0.38 Bq/kg for Ra-226; from 1.20 ± 0.50 up to 8.07 ± 0.96 for Th-232 and from 212.90 ± 10.80 up to 377.00 ± 17.78 for K-40. Further, the study will be extended to a larger number of dog food brands and also to cat food brands available in Brazil and eventual radiological consequences of absorbed dose will be assessed. (authors)

  12. Instrumental neutron activation analysis of some fossil samples from Romanian palaeolontologic sites

    International Nuclear Information System (INIS)

    During the fossilization process, elemental contents of the buried materials are modified by different physical, chemical and biological factors, such as ground water flow and degree of aeration, chemical composition of the soil, bacterial activity, the process being influenced by the climatical conditions. Bone tissue, by the calcium phosphate mineral (hydroxyapatite) in the external part and organic component (fat and collagen) in the inner part, has proved to be a proper substrate for minor elements accumulation. The uniform increasing of certain elemental concentrations during the fossilization process is generally used in palaeoscience for the age dating. Instrumental neutron activation analysis (INAA) method was used by us to determine Al, As, Au, Ba, Br, Ca, Co, Cr, Cs, Fe, Hf, K, Mg, Mn, Na, Ni, Rb, Sb, Sc, Se, Sr, Th, U, V, Zn, and of the rare earth elements Ce, Eu, La, Lu, Nd, Sm, Tb, Yb contents of two different fossil materials discovered in Romania during 1995-1996: Elephas primigenius mammoth mandible bone (1.5-2 million years age) and Pecten solarium shell (20-25 million years age). Mammoth mandible bone samples were taken both from the external and the internal part of the bone. Shell fragments were taken in association with the surrounding rock samples. Irradiations were carried out at the WWR-S reactor in Bucharest (neutron fluence rate 2.3 x 1012 cm-2 s-1 and at the TRIGA reactor in Pitesti (neutron fluence rate 5 x 1013 cm-2 s-1. For the mammoth mandible bone (relative high contents of U and P) corrections were done for the uranium fission and (n,γ)β- contribution to Ce, La, Nd and Sm concentrations, and for the phosphorus interference in Al determination. It was taken into account that 141 Ce, 140 La, 147 Nd, 153 Sm isotopes are originated not only by the neutron activation reactions of these elements, but also from the beta- decay chains of the uranium fission products; for 153 Sm, spectral interference with 103.65 keV X-ray of 239 Pu (by

  13. ZZ MATXSLIBJ33, JENDL-3.3 based, 175 N-42 photon groups (VITAMIN-J) MATXS library for discrete ordinates multi-group

    International Nuclear Information System (INIS)

    1 - Description of program or function: JENDL-3.3 based, 175 neutron-42 photon groups (VITAMIN-J) MATXS library for discrete ordinates multi-group transport codes. Format: MATXS. Number of groups: 175 neutron, 42 gamma-ray. Nuclides: 337 nuclides contained in JENDL-3.3: H-1, H-2, He-3, He-4, Li-6, Li-7, Be-9, B-10, B-11, C-Nat, N-14, N-15, O-16, F-19, Na-23, Mg-24, Mg-25, Mg-26, Al-27, Si-28, Si-29, Si-30, P-31, S-32, S-33, S-34, S-36, Cl-35, Cl-37, Ar-40, K-39, K-40, K-41, Ca-40, Ca-42, Ca-43, Ca-44, Ca-46, Ca-48, Sc-45, Ti-46, Ti-47, Ti-48, Ti-49, Ti-50, V-Nat, Cr-50, Cr-52, Cr-53, Cr-54, Mn-55, Fe-54, Fe-56, Fe-57, Fe-58, Co-59, Ni-58, Ni-60, Ni-61, Ni-62, Ni-64, Cu-63, Cu-65, Ga-69, Ga-71, Ge-70, Ge-72, Ge-73, Ge-74, Ge-76, As-75, Se-74, Se-76, Se-77, Se-78, Se-79, Se-80, Se-82, Br-79, Br-81, Kr-78, Kr-80, Kr-82, Kr-83, Kr-84, Kr-85, Kr-86, Rb-85, Rb-87, Sr-86, Sr-87, Sr-88, Sr-89, Sr-90, Y-89, Y-91, Zr-90, Zr-91, Zr-92, Zr-93, Zr-94, Zr-95, Zr-96, Nb-93, Nb-94, Nb-95, Mo-92, Mo-94, Mo-95, Mo-96, Mo-97, Mo-98, Mo-99, Mo-100, Tc-99, Ru-96, Ru-98, Ru-99, Ru-100, Ru-101, Ru-102, Ru-103, Ru-104, Ru-106, Rh-103, Rh-105, Pd-102, Pd-104, Pd-105, Pd-106, Pd-107, Pd-108, Pd-110, Ag-107, Ag-109, Ag-110m, Cd-106, Cd-108, Cd-110, Cd-111, Cd-112, Cd-113, Cd-114, Cd-116, In-113, In-115, Sn-112, Sn-114, Sn-115, Sn-116, Sn-117, Sn-118, Sn-119, Sn-120, Sn-122, Sn-123, Sn-124, Sn-126, Sb-121, Sb-123, Sb-124, Sb-125, Te-120, Te-122, Te-123, Te-124, Te-125, Te-126, Te-127m, Te-128, Te-129m, Te-130, I-127, I-129, I-131, Xe-124, Xe-126, Xe-128, Xe-129, Xe-130, Xe-131, Xe-132, Xe-133, Xe-134, Xe-135, Xe-136, Cs-133, Cs-134, Cs-135, Cs-136, Cs-137, Ba-130, Ba-132, Ba-134, Ba-135, Ba-136, Ba-137, Ba-138, Ba-140, La-138, La-139, Ce-140, Ce-141, Ce-142, Ce-144, Pr-141, Pr-143, Nd-142, Nd-143, Nd-144, Nd-145, Nd-146, Nd-147, Nd-148, Nd-150, Pm-147, Pm-148, Pm-148m, Pm-149, Sm-144, Sm-147, Sm-148, Sm-149, Sm-150, Sm-151, Sm-152, Sm-153, Sm-154, Eu-151, Eu-152, Eu-153, Eu-154, Eu-155, Eu

  14. Opening remarks: Preface

    International Nuclear Information System (INIS)

    was the beginning of a new scientific era of opportunity and discovery using the radionuclides injected into the environment from weapons tests as a tool for studying such phenomena as atmospheric chemistry and ecological transfer processes and for developing new methods for the measurement and analysis of low levels of radioactive materials in environmental samples. Webb (1949), of the Eastman Kodak Company of Rochester, New York, was the first to report an occurrence of long-range fallout. He observed 'a new type of radioactive contaminant' in paper packing materials used to separate sensitive photographic films. This observation was made shortly after the first nuclear detonation on 16 July 1945 at Alamogordo, New Mexico, and the two events were immediately linked. During the war years Kodak had encountered radium-contaminated paper, caused by paper and cardboard salvaged and recycled from war plants where radium instrument dials were prepared. The company had therefore instigated a radiation-monitoring program. The paper contaminated by fallout was discovered in August 1945 in paper material that had been produced in Indiana from corn stalks grown in Iowa, some 1,600 km distant from the New Mexico test location. The contamination, identified as 141Ce, had originated from dust particles deposited from the atmosphere, transferred to river water, and filtered out onto the paper raw material. Even though fallout was detected far from New Mexico as a result of the Trinity test, the systematic monitoring of long-range fallout did not begin until February 1951, 50 y ago. At that time, the testing of nuclear weapons in the atmosphere began in earnest and it was first recognized that fallout formed in the tests could become widely distributed downrange of the test site. Thus, it seemed appropriate for the NCRP at their 2001 annual meeting to mark this 50 y since the initiation of the global fallout monitoring and research programs by providing a forum to look back at the

  15. A study on the Methodology for Integrated Safety Assessment for Accidental Analysis on LILW managed in Temporary Storage Facility (TSF) at NPP

    Energy Technology Data Exchange (ETDEWEB)

    Ahn, Min Ho; Lee, Kun Jai [Korea Advanced Institute of Science and Technology, 335 Gwahak-ro, yuseong-gu, Daejeon 305-701 (Korea, Republic of); Choi, Kyung Woo [Korea Institute of Nuclear Safety, 34 Gwahak-ro, yuseong-gu, Daejeon 305-338 (Korea, Republic of)

    2010-07-01

    dose assessment were considered: {sup 3}H, {sup 14}C, {sup 55}Fe, {sup 58}Co, {sup 60}Co, {sup 59}Ni, {sup 63}Ni, {sup 90}Sr, {sup 94}Nb, {sup 99}Tc, {sup 129}I, {sup 137}Cs, and {sup 144}Ce. According to the U.S. NRC Regulatory Guide 1.145, the atmospheric dispersion factors (?/Q) for workers and public were derived by meteorological data measured in Kori NPP: wind speed, wind direction, and atmospheric stability. For the evaluation of internal exposure, the breathing rate (m{sup 3}/sec) described in U.S. NRC Regulatory Guide 1.8 was considered. In conclusion: Based on the MLD method, the dropping of drums and fire were used to evaluate the exposure dose by arbitrary accidents originating in the TSF for LILW management. For the exposure dose assessment, a variety of parameters were considered: the amount of radionuclides released (Bq), the atmospheric dispersion factor for workers and public (sec/m{sup 3}), the breathing rate for internal exposure (m{sup 3}/sec), and the dose conversion factor for internal and external exposure (mSv/Bq, mSv/hr per Bq/m{sup 3}). Furthermore, an exposure dose assessment was conducted in terms of the effective dose and the thyroid equivalent dose for workers and public, considering the release rates of the radionuclides stemming from the dropping of drums and fire. The number of damaged drums was taken as 2 for the dropping of drums and 40 for fire relative to each waste stream. Seven waste streams were considered: the general DAW (200 L), the shielded DAW (200 L), the concentrated waste solidified by cement (200 L), the concentrated waste stabilized by paraffin (200 L), the general spent resin (200 L), the spent resin solidified by cement (200 L), and the general spent filter (200 L). The effective doses resulted from the dropping of drums were in the range of 4.95 E-15 to 2.19 E- 7 mSv for workers and 9.21 E-17 to 1.34 E-9 mSv for public. Also the thyroid equivalent doses originating from the dropping of drums were in the range of 3

  16. ZZ FSXJ32, MCNP nuclear data library based on JENDL-3.2. ZZ FSXLIBJ33, MCNP nuclear data library based on JENDL-3.3

    International Nuclear Information System (INIS)

    -103, Rh-105, Pd-102, Pd-104, Pd-105, Pd-106, Pd-107, Pd-108, Pd-110, Ag-107, Ag-109, Ag-110m,Cd-106, Cd-108, Cd-110, Cd-111, Cd-112, Cd-113, Cd-114, Cd-116, In-113, In-115, Sn-112, Sn-114, Sn-115, Sn-116, Sn-117, Sn-118, Sn-119, Sn-120, Sn-122, Sn-123, Sn-124, Sn-126, Sb-121, Sb-123, Sb-124, Sb-125, Te-120, Te-122, Te-123, Te-124, Te-125, Te-126, Te-127m,Te-128, Te-129m,Te-130, I -127, I -129, I -131, Xe-124, Xe-126, Xe-128, Xe-129, Xe-130, Xe-131, Xe-132, Xe-133, Xe-134, Xe-135, Xe-136, Cs-133, Cs-134, Cs-135, Cs-136, Cs-137, Ba-130, Ba-132, Ba-134, Ba-135, Ba-136, Ba-137, Ba-138, Ba-140, La-138, La-139, Ce-140, Ce-141, Ce-142, Ce-144, Pr-141, Pr-143, Nd-142, Nd-143, Nd-144, Nd-145, Nd-146, Nd-147, Nd-148, Nd-150, Pm-147, Pm-148, Pm-148m,Pm-149, Sm-144, Sm-147, Sm-148, Sm-149, Sm-150, Sm-151, Sm-152, Sm-153, Sm-154, Eu-151, Eu-152, Eu-153, Eu-154, Eu-155, Eu-156, Gd-152, Gd-154, Gd-155, Gd-156, Gd-157, Gd-158, Gd-160, Tb-159, Er-162, Er-164, Er-166, Er-167, Er-168, Er-170, Hf-174, Hf-176, Hf-177, Hf-178, Hf-179, Hf-180, Ta-181, W-182, W-183, W-184, W-186, Hg-196, Hg-198, Hg-199, Hg-200, Hg-201, Hg-202, Hg-204, Pb-204, Pb-206, Pb-207, Pb-208, Bi-209, Ra-223, Ra-224, Ra-225, Ra-226, Ac-225, Ac-226, Ac-227, Th-227, Th-228, Th-229, Th-230, Th-232, Th-233, Th-234, Pa-231, Pa-232, Pa-233, U-232, U-233, U-234, U-235, U-236, U-237, U-238, Np-235, Np-236, Np-237, Np-238, Np-239, Pu-236, Pu-237, Pu-238, Pu-239, Pu-240, Pu-241, Pu-242, Pu-244, Pu-246, Am-241, Am-242, Am-242m, Am-243, Am-244, Am-244m, Cm-240, Cm-241, Cm-242, Cm-243, Cm-244, Cm-245, Cm-246, Cm-247, Cm-248, Cm-249, Cm-250, Bk-247, Bk-249, Bk-250, Cf-249, Cf-250, Cf-251, Cf-252, Cf-254, Es-254, Es-255, Fm-255 Temperatures: 300 K. Origin: JENDL-3.3. Thermal scattering: Free gas model Kerma factors are provided. The original JENDL-3.3 has two problems in Am-241 data. One is the missing of MF/MT=4/18, and the other is the incorrect neutron spectra for MT=18 below 500 keV. The updated data have been produced as JENDL-3