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Sample records for 240pu 243am 209bi

  1. Fabrication of 12% {sup 240}Pu calorimetry standards

    Energy Technology Data Exchange (ETDEWEB)

    Long, S.M.; Hildner, S.; Gutierrez, D.; Mills, C.; Garcia, W.; Gurule, C.

    1995-08-01

    Throughout the DOE complex, laboratories are performing calorimetric assays on items containing high burnup plutonium. These materials contain higher isotopic range and higher wattages than materials previously encountered in vault holdings. Currently, measurement control standards have been limited to utilizing 6% {sup 240}Pu standards. The lower isotopic and wattage value standards do not complement the measurement of the higher burnup material. Participants of the Calorimetry Exchange (CALEX) Program have identified the need for new calorimetric assay standards with a higher wattage and isotopic range. This paper describes the fabrication and verification measurements of the new CALEX standard containing 12% {sup 240}Pu oxide with a wattage of about 6 to 8 watts.

  2. Radiationless transition probabilities in muonic 209Bi

    International Nuclear Information System (INIS)

    The probability for non-radiative (n.r.) excitations in muonic 209Bi was determined from a (μ-, γγ)-measurement by comparing the intensities of muonic X-ray transitions in single and coincidence spectra. The values of Pn.r.(3p→1s)=(17.9±2.0)% and Pn.r.(3d→1s)=(3.0±2.2)% were measured for the first time. The strength of the n.r. decay of the 2p-level was found to be (4.2±2.2)%. The n.r. transition probabilities of two subcomplexes of the (2p→1s)-transition leading to different mean excitation energies are (3.2±1.8)% and (5.0±2.0)%, respectively. (orig.)

  3. Vertical distributions of radionuclides ((239+240)Pu, (240)Pu/(239)Pu, and (137)Cs) in sediment cores of Lake Bosten in Northwestern China.

    Science.gov (United States)

    Liao, Haiqing; Bu, Wenting; Zheng, Jian; Wu, Fengchang; Yamada, Masatoshi

    2014-04-01

    Artificial radionuclides ((137)Cs, (239+240)Pu, (241)Pu, (241)Am) deposited in lacustrine sediments have been used for dating as well as radionuclide source identification. In the present work, we investigated the vertical distributions of (239+240)Pu and (137)Cs activities, (240)Pu/(239)Pu atom ratios, and (239+240)Pu/(137)Cs activity ratios in sediment cores collected from Lake Bosten, which is the lake closest to the Lop Nor Chinese Nuclear Weapon Test site in northwestern China. Uniformly high concentrations of (239+240)Pu and (137)Cs were found in the upper layers deposited since 1964 in the sediment cores, and these were controlled by the resuspension of soil containing radionuclides from the nearby land surface. As the Chinese nuclear tests varied remarkably in yield, the mixing of the tropospheric deposition from these tests and the stratospheric deposition of global fallout has led to a (240)Pu/(239)Pu atom ratio that is similar to that of global fallout and to a (239+240)Pu/(137)Cs activity ratio that is slightly higher than that of global fallout. However, a low (240)Pu/(239)Pu atom ratio of 0.080 and high (239+240)Pu/(137)Cs activity ratio of 0.087, significantly different from the global fallout values, were observed in one sediment core (07BS10-2), indicating the inhomogenous tropospheric deposition from the Chinese nuclear tests in Lake Bosten during 1967-1973. These results are important to understand the influence of the CNTs on the radionuclide contamination in Lake Bosten.

  4. Concentrations of sup(239,240)Pu and 241Am in drinking water and organic fertilizer

    International Nuclear Information System (INIS)

    As part of an investigation of the chemistry and aquatic distribution of fallout-derived sup(239,240)Pu and 241Am in the aquatic environment a study has been made of the concentration of these nuclides in the drinking water and organic fertilizer, distributed to the populace of the Chicago area. The results clearly indicate that the concentration of sup(239,240)Pu is always lower in the water which has been treated at the Chicago Central Water Filtration Plant than in the raw water before treatment. Raw water levels are consistent with normal levels of sup(239,240)PU found in Lake Michigan waters which are approx 6 orders of magnitude below the maximum permissible concentration standard for drinking water. An additional possible source of sup(239,240)Pu and 241Am to humans can be through the distribution of the organic fertilizer, 'Nu Earth', by the Metropolitan Sanitary District, free of charge, for the use in home gardens. 'Nu Earth' consists primarily of sediment from an Imhoff Process which has been air-dried and aged in large, open-air piles. Samples of this organic fertilizer were analysed for sup(239,240)Pu and 241Am. The results indicate that there is little evidence to indicate that sup(239,240)Pu in drinking water or sup(239,240)Pu and 241Am from organic sludge will be health hazards in the Chicago area under current conditions. (U.K.)

  5. Worldwide data on fluxes of 239,240Pu, 238Pu to the oceans

    International Nuclear Information System (INIS)

    According to measurements (GEOSECS) the world's oceans contain approximately 16 PBq 239,240Pu, of which one-fourth is in the Atlantic and three-fourths in the Pacific Ocean. The expected inventory (from nuclear weapons testing) in the world's oceans is 12 PBq 239,240Pu including local fallout at the test sites. In the Irish Sea a local contamination of 0.3 PBq 239,240Pu from the Sellafield reprocessing plant resides in the sediments. No other sources than fallout and reprocessing add significantly to the 239,240Pu inventories in the oceans. The discrepancy between measurements and expectations are assumed to be due to an underestimate of the rainfall and dry fallout (seaspray) and thus of the Pu-deposition over the oceans, but may also to some degree be due to inadequate sampling

  6. Plutonium isotopes 238Pu, 239+240Pu, 241Pu and 240Pu/239Pu atomic ratios in the southern Baltic Sea ecosystem

    Directory of Open Access Journals (Sweden)

    Dagmara I. Strumińska-Parulska

    2010-09-01

    Full Text Available The paper summarizes the results of plutonium findings in atmospheric fallout samples and marine samples from the southern Baltic Sea during our research in 1986-2007. The activities of 238Pu and 239+240Pu isotopes were measured with an alpha spectrometer. The activities of 241Pu were calculated indirectly by 241Am activity measurements 16-18 years after the Chernobyl accident. The 240Pu/239Pu atomic ratios were measured using accelerator mass spectrometry (AMS. The 241Pu activities indicate that the main impact of the Chernobyl accident was on the plutonium concentration in the components of the Baltic Sea ecosystem examined in this work. The highest 241Pu/239+240Pu activity ratio was found in sea water (140 ± 33. The AMS measurements of atmospheric fallout samples collected during 1986 showed a significant increase in the 240Pu/239Pu atomic ratio from 0.29 ± 0.04 in March 1986 to 0.47 ± 0.02 in April 1986.

  7. Multinucleon photonuclear reactions on {sup 209}Bi: Experiment and evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Belyshev, S.S.; Kurilik, A.S. [Lomonosov Moscow State University, Department of Physics, Moscow (Russian Federation); Filipescu, D.M.; Tesileanu, O. [Extreme Light Infrastructure - Nuclear Physics/Horia Hulubei National Institute for R and D in Physics and Nuclear Engineering, Bucharest-Magurele (Romania); Gheoghe, I. [Extreme Light Infrastructure - Nuclear Physics/Horia Hulubei National Institute for R and D in Physics and Nuclear Engineering, Bucharest-Magurele (Romania); University of Bucharest, Faculty of Physics, Bucharest-Magurele (Romania); Ishkhanov, B.S. [Lomonosov Moscow State University, Department of Physics, Moscow (Russian Federation); Skobeltsyn Institute of Nuclear Physics, Lomonosov Moscow State University, Moscow (Russian Federation); Khankin, V.V.; Kuznetsov, A.A.; Orlin, V.N.; Peskov, N.N.; Stopani, K.A.; Varlamov, V.V. [Skobeltsyn Institute of Nuclear Physics, Lomonosov Moscow State University, Moscow (Russian Federation)

    2015-06-15

    Photon activation technique using bremsstrahlug with end-point energy 55.6 MeV is used to induce photonuclear reactions in a {sup 209}Bi target. Absolute yields and integrated cross sections of multiparticle reactions (γ, 2n-6n), (γ, 4n1p), and (γ, 5n1p) are obtained. The results are compared to predictions of statistical models using systematical and microscopic description of photoabsorption and to the result of evaluation of the partial photoneutron reaction cross sections. Based on a comparison with existing experimental photoneutron cross sections and model calculations, we make a conclusion that neutron multiplicity assignment in available photoneutron cross sections on {sup 209}Bi can be corrected and evaluated cross sections of (γ, 1n) and (γ, 2n) are obtained that are in an agreement with the obtained experimental results. (orig.)

  8. Extension of 239+240Pu sediment geochronology to coarse-grained marine sediments

    Science.gov (United States)

    Kuehl, Steven A.; Ketterer, Michael E.; Miselis, Jennifer L.

    2012-01-01

    Sediment geochronology of coastal sedimentary environments dominated by sand has been extremely limited because concentrations of natural and bomb-fallout radionuclides are often below the limit of measurement using standard techniques. ICP-MS analyses of 239+240Pu from two sites representative of traditionally challenging (i.e., low concentration) environments provide a "proof of concept" and demonstrate a new application for bomb-fallout radiotracers in the study of sandy shelf-seabed dynamics. A kasten core from the New Zealand shelf in the Southern Hemisphere (low fallout), and a vibracore from the sandy nearshore of North Carolina (low particle surface area) both reveal measurable 239+240Pu activities at depth. In the case of the New Zealand site, independently verified steady-state sedimentation results in a 239+240Pu profile that mimics the expected atmospheric fallout. The depth profile of 239+240Pu in the North Carolina core is more uniform, indicating significant sediment resuspension, which would be expected in this energetic nearshore environment. This study, for the first time, demonstrates the utility of 239+240Pu in the study of sandy environments, significantly extending the application of bomb-fallout isotopes to coarse-grained sediments, which compose the majority of nearshore regions.

  9. Modeling and production of 240Am by deuteron-induced activation of a 240Pu target

    International Nuclear Information System (INIS)

    A novel reaction pathway for production of 240Am is reported. Models of reaction cross-sections in EMPIRE II suggest that deuteron-induced activation of a 240Pu target produces maximum yields of 240Am from 11.5 MeV incident deuterons. This activation had not been previously reported in the literature. A 240Pu target was activated under the modeled optimum conditions to produce 240Am. The modeled cross-section for the 240Pu(d, 2n)240Am reaction is on the order of 20–30 mbarn, but the experimentally estimated value is 5.6 ± 0.2 mbarn. We discuss reasons for the discrepancy as well as production of other Am isotopes that contaminate the final product

  10. Modeling and production of 240Am by deuteron-induced activation of a 240Pu target

    Energy Technology Data Exchange (ETDEWEB)

    Finn, Erin C.; McNamara, Bruce K.; Greenwood, Lawrence R.; Wittman, Richard S.; Soderquist, Chuck Z.; Woods, Vincent T.; VanDevender, Brent A.; Metz, Lori A.; Friese, Judah I.

    2015-02-01

    A novel reaction pathway for production of 240Am is reported. Models of reaction cross-sections in EMPIRE II suggests that deuteron-induced activation of a 240Pu target produces maximum yields of 240Am from 11.5 MeV incident deuterons. This activation had not been previously reported in the literature. A 240Pu target was activated under the modeled optimum conditions to produce 240Am. The modeled cross-section for the 240Pu(d, 2n)240Am reaction is on the order of 20-30 mbarn, but the experimentally estimated value is 5.3 ± 0.2 mbarn. We discuss reasons for the discrepancy as well as production of other Am isotopes that contaminate the final product.

  11. Preparation and high intensity heavy ion irradiation tests of intermetallic 243Am/Pd targets

    International Nuclear Information System (INIS)

    Previously reported preparation method for Pd-based intermetallic targets (Usoltsev, et al., 2012) [1] has been successfully applied for producing two stationary 243Am/Pd targets. Both targets have been irradiated at the U-400 cyclotron at Flerov Laboratory of Nuclear Reactions Dubna (Russian Federation) using high intensity beams (up to 0.83 μApart) of 48Ca18+. Alpha-particle spectroscopy and light microscopy allowed for a comprehensive characterization of the intermetallic targets before and after irradiation. A natNd/Pd intermetallic target and a solely electroplated 243Am/Ti target were similarly investigated for comparison

  12. Repolarization of Negative Muons by Polarized $^{209}$Bi Nuclei

    CERN Document Server

    Kadono, R; Ishikawa, T; Nishiyama, K; Nagamine, K; Yamazaki, T; Bosshard, A; Döbeli, M; van Elmbt, L; Schaad, M; Truöl, P; Bay, A; Perroud, J P; Deutsch, J; Tasiaux, B; Hagn, E

    2016-01-01

    A large $\\mu^-$ polarization was achieved in muonic Bi atoms with the help of the strong hyperfine field in a polarized nuclear target. Using $^{209}$Bi nuclei polarized to ($59\\pm9$)% in ferromagnetic BiMn, we observed a $\\mu$-$e$ decay asymmetry of ($13.1\\pm3.9$)%, which gives $\\mu^-$ polarization per nuclear polarization equal to $-1.07\\pm 0.35$. This value is almost consistent with $-0.792$ calculated for nuclei with spin $I= \\frac{9}{2}$ and a positive magnetic moment under the assumption that the hyperfine interaction becomes effective in the lowest muonic states.

  13. Presence of plutonium isotopes, {sup 239}Pu and {sup 240}Pu, in soils from Chile

    Energy Technology Data Exchange (ETDEWEB)

    Chamizo, E., E-mail: echamizo@us.es [Centro Nacional de Aceleradores, Avda. Thomas Alba Edison, 7, 41092 Sevilla (Spain); Garcia-Leon, M., E-mail: manugar@us.es [Departamento de Fisica Atomica, Molecular y Nuclear, Universidad de Sevilla, Avda. Reina Mercedes sn, 41012 Seville (Spain); Peruchena, J.I., E-mail: jiperuchena@gmail.com [Centro Nacional de Aceleradores, Avda. Thomas Alba Edison, 7, 41092 Sevilla (Spain); Cereceda, F., E-mail: francisco.cereceda@usm.cl [Laboratorio de Quimica Ambiental, Centro de Tecnologias Ambientales (CETAM), Universidad Tecnica Federico Santa Maria, Casilla 110-V, Valparaiso (Chile); Vidal, V., E-mail: victor.vidal@usm.cl [Laboratorio de Quimica Ambiental, Centro de Tecnologias Ambientales (CETAM), Universidad Tecnica Federico Santa Maria, Casilla 110-V, Valparaiso (Chile); Pinilla, E., E-mail: epinilla@unex.es [Departamento de Quimica Analitica, Facultad de Ciencias, Universidad de Extremadura, Avda. de Elvas sn, 06071 Badajoz (Spain); Miro, C., E-mail: cmiro@unex.es [Departamento de Fisica Aplicada, Universidad de Extremadura, Avda. de la Universidad sn, 10071 Caceres (Spain)

    2011-12-15

    Plutonium is present in every environmental compartment, due to a variety of nuclear activities. The Southern Hemisphere has received about 20% of the global {sup 239}Pu and {sup 240}Pu environmental inventory, with an important contribution of the so-called tropospheric fallout from both the atmospheric nuclear tests performed in the French Polynesia and in Australia by France and United Kingdom, respectively. In this work we provide new data on the impact of these tests to South America through the study of {sup 239}Pu and {sup 240}Pu in soils from different areas of Northern, Central and Southern Chile. The obtained results point out to the presence of debris from the French tests in the 20-40 Degree-Sign Southern latitude range, with {sup 240}Pu/{sup 239}Pu atomic ratios quite heterogeneous and ranging from 0.02 to 0.23. They are significantly different from the expected one for the global fallout in the Southern Hemisphere for the 30-53 Degree-Sign S latitude range (0.185 {+-} 0.047), but they follow the same trend as the reported values by the Department of Energy of United States for other points with similar latitudes. The {sup 239+240}Pu activity inventories show as well a wider variability range in that latitude range, in agreement with the expected heterogeneity of the contamination.

  14. Evaluation both level and 239+240Pu spatial contamination of the Lira object and the neighbouring areas

    International Nuclear Information System (INIS)

    In the work the generalization of considerable data collection for revealing of 239+240Pu content range discriminative for Lira object and neighbouring areas is carried out. 239+240Pu mean specific activity in the soil cover surface and in the Berezovka River bottom sedimentations are determined. The correlation dependence between 239+240Pu artificial radionuclides and 137Cs is revealed. The general source of artificial radionuclide origination for examined isotopes is shown up, and it is related with global radioactive fallout

  15. Prompt fission γ -ray spectrum characteristics from 240Pu(sf ) and 242Pu(sf )

    Science.gov (United States)

    Oberstedt, S.; Oberstedt, A.; Gatera, A.; Göök, A.; Hambsch, F.-J.; Moens, A.; Sibbens, G.; Vanleeuw, D.; Vidali, M.

    2016-05-01

    In this paper we present first results for prompt fission γ -ray spectra (PFGS) characteristics from the spontaneous fission (sf) of 240Pu and 242Pu. For 242Pu(sf ) we obtained, after proper unfolding of the detector response, an average energy per photon ɛ¯γ=(0.843 ±0.012 ) MeV, an average multiplicity M¯γ=(6.72 ±0.07 ) , and an average total γ -ray energy release per fission E¯γ ,tot = (5.66 ± 0.06) MeV. The 240Pu(sf ) emission spectrum was obtained by applying a so-called detector-response transformation function determined from the 242Pu spectrum measured in exactly the same geometry. The results are an average energy per photon ɛ¯γ=(0.80 ±0.07 ) MeV, the average multiplicity M¯γ = (8.2 ± 0.4), and an average total γ -ray energy release per fission E¯γ ,tot = (6.6 ± 0.5) MeV. The PFGS characteristics for 242Pu(sf ) are in very good agreement with those from thermal-neutron-induced fission on 241Pu and scales well with the corresponding prompt neutron multiplicity. Our results in the case of 240Pu(sf ), although drawn from a limited number of events, show a significantly enhanced average multiplicity and average total energy, but may be understood from a different fragment yield distribution in 240Pu(sf ) compared to that of 242Pu(sf ).

  16. Measurement of the ${240}$Pu(n,f) reaction cross-section

    CERN Multimedia

    Following proposal CERN-INTC-2010-042 / INTC-P-280 (“Measurement of the fission cross-section of $^{240}$Pu and $^{242}$Pu at CERN’s n_TOF Facility”), the parallel measurement of the $^{240}$Pu(n,f) and $^{242}$Pu(n,f) reaction cross-sections was carried out at n_TOF EAR-1. While the $^{242}$Pu measurement was successful, unexpected sample-induced damage to the detectors caused by the high α-activity of the 240Pu samples resulted in a deterioration of the detector performance over the data taking period of several months, which compromised the measurement. This obstacle can be eliminated by performing the measurement in EAR-2, where the higher neutron flux will allow collecting data in a much shorter time, thus preventing the degradation of the detectors. In addition to this obvious advantage, the measurement would also benefit from the stronger suppression of the sample-induced α-background, due to the shorter times-of-flight involved.

  17. Background distributions of 239+240Pu and 137Cs of upland soil in Rokkasho, Japan

    International Nuclear Information System (INIS)

    The background distributions of Pu and 137Cs in soil were investigated in Rokkasho, Aomori Prefecture, where the first commercial nuclear fuel reprocessing plant in Japan is now being constructed. Soil core samples to 1 m depth were collected at 13 upland fields in Rokkasho and control sites in Hachinohe and Hirosaki. Since fields under yam (Dioscorea babatus) cultivation, which is a common crop in Rokkasho, were dug to approximately 1 m depth at harvesting, depth profiles of fallout radionuclides are heavily disturbed for most fields in Rokkasho. The mean inventories of 239+240Pu and 137Cs in three fields with no yam cultivation history were 116 Bq m-2 and 3.4 kBq m-2, respectively and similar to values in Hachinohe. However, the inventories were approximately a half of those in Hirosaki. The mean ratio of 239Pu/240Pu for all studied fields was 0.18±0.04, and similar to that of global fallout. The Pu concentrations correlate very well with 137Cs (r=0.97) in spite of heavy disturbance of soil, and the ratio of 239+240Pu/137Cs was 0.037±0.007, which is a typical value for global fallout. (author)

  18. Neutron inelastic-scattering cross sections of 232Th, 233U, 235U, 238U, 239Pu and 240Pu

    International Nuclear Information System (INIS)

    Differential-neutron-emission cross sections of 232Th, 233U, 235U, 238U, 239Pu and 240Pu are measured between approx. = 1.0 and 3.5 MeV with the angle and magnitude detail needed to provide angle-integrated emission cross sections to approx. 232Th, 233U, 235U and 238U inelastic-scattering values, poor agreement is observed for 240Pu, and a serious discrepancy exists in the case of 239Pu

  19. Measurements of neutron cross section of the {sup 243}Am(n,{gamma}){sup 244}Am reaction

    Energy Technology Data Exchange (ETDEWEB)

    Hatsukawa, Yuichi; Shinohara, Nobuo; Hata, Kentaro [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    1998-03-01

    The effective thermal neutron cross section of {sup 243}Am(n,{gamma}){sup 244}Am reaction was measured by the activation method. Highly-purified {sup 243}Am target was irradiated in an aluminum capsule by using a research reactor JRR-3M. The tentative effective thermal neutron cross sections are 3.92 b, and 84.44 b for the production of {sup 244g}Am and {sup 244m}Am, respectively. (author)

  20. A multi-radionuclide approach to evaluate the suitability of (239+240)Pu as soil erosion tracer.

    Science.gov (United States)

    Meusburger, Katrin; Mabit, Lionel; Ketterer, Michael; Park, Ji-Hyung; Sandor, Tarjan; Porto, Paolo; Alewell, Christine

    2016-10-01

    Fallout radionuclides have been used successfully worldwide as tracers for soil erosion, but relatively few studies exploit the full potential of plutonium (Pu) isotopes. Hence, this study aims to explore the suitability of the plutonium isotopes (239)Pu and (240)Pu as a method to assess soil erosion magnitude by comparison to more established fallout radionuclides such as (137)Cs and (210)Pbex. As test area an erosion affected headwater catchment of the Lake Soyang (South Korea) was selected. All three fallout radionuclides confirmed high erosion rates for agricultural sites (>25tha(-1)yr(-1)). Pu isotopes further allowed determining the origin of the fallout. Both (240)Pu/(239)Pu atomic ratios and (239+240)Pu/(137)Cs activity ratios were close to the global fallout ratio. However, the depth profile of the (239+240)Pu/(137)Cs activity ratios in undisturbed sites showed lower ratios in the top soil increments, which might be due to higher migration rates of (239+240)Pu. The activity ratios further indicated preferential transport of (137)Cs from eroded sites (higher ratio compared to the global fallout) to the depositional sites (smaller ratio). As such the (239+240)Pu/(137)Cs activity ratio offered a new approach to parameterize a particle size correction factor that can be applied when both (137)Cs and (239+240)Pu have the same fallout source. Implementing this particle size correction factor in the conversion of (137)Cs inventories resulted in comparable estimates of soil loss for (137)Cs and (239+240)Pu. The comparison among the different fallout radionuclides highlights the suitability of (239+240)Pu through less preferential transport compared to (137)Cs and the possibility to gain information regarding the origin of the fallout. In conclusion, (239+240)Pu is a promising soil erosion tracer, however, since the behaviour i.e. vertical migration in the soil and lateral transport during water erosion was shown to differ from that of (137)Cs, there is a clear

  1. A multi-radionuclide approach to evaluate the suitability of (239+240)Pu as soil erosion tracer.

    Science.gov (United States)

    Meusburger, Katrin; Mabit, Lionel; Ketterer, Michael; Park, Ji-Hyung; Sandor, Tarjan; Porto, Paolo; Alewell, Christine

    2016-10-01

    Fallout radionuclides have been used successfully worldwide as tracers for soil erosion, but relatively few studies exploit the full potential of plutonium (Pu) isotopes. Hence, this study aims to explore the suitability of the plutonium isotopes (239)Pu and (240)Pu as a method to assess soil erosion magnitude by comparison to more established fallout radionuclides such as (137)Cs and (210)Pbex. As test area an erosion affected headwater catchment of the Lake Soyang (South Korea) was selected. All three fallout radionuclides confirmed high erosion rates for agricultural sites (>25tha(-1)yr(-1)). Pu isotopes further allowed determining the origin of the fallout. Both (240)Pu/(239)Pu atomic ratios and (239+240)Pu/(137)Cs activity ratios were close to the global fallout ratio. However, the depth profile of the (239+240)Pu/(137)Cs activity ratios in undisturbed sites showed lower ratios in the top soil increments, which might be due to higher migration rates of (239+240)Pu. The activity ratios further indicated preferential transport of (137)Cs from eroded sites (higher ratio compared to the global fallout) to the depositional sites (smaller ratio). As such the (239+240)Pu/(137)Cs activity ratio offered a new approach to parameterize a particle size correction factor that can be applied when both (137)Cs and (239+240)Pu have the same fallout source. Implementing this particle size correction factor in the conversion of (137)Cs inventories resulted in comparable estimates of soil loss for (137)Cs and (239+240)Pu. The comparison among the different fallout radionuclides highlights the suitability of (239+240)Pu through less preferential transport compared to (137)Cs and the possibility to gain information regarding the origin of the fallout. In conclusion, (239+240)Pu is a promising soil erosion tracer, however, since the behaviour i.e. vertical migration in the soil and lateral transport during water erosion was shown to differ from that of (137)Cs, there is a clear

  2. {sup 239+240}Pu in the Barents Sea Regions. Sources and radioecological assessment

    Energy Technology Data Exchange (ETDEWEB)

    Iosjpe, Mikhail [Norwegian Radiation Protection Authority, P.O. Box 55, N-1332 Oesteraas (Norway)

    2014-07-01

    The radioecological assessment for {sup 239+240}Pu in the Barents sea regions was made using the compartment modelling approach. The following sources of radioactive contamination were under consideration: global fallout from atmospheric testing of nuclear weapons, transport of {sup 239+240}Pu from the Sellafield and La Hauge nuclear plants and underwater testing of nuclear weapons in Chernaya Bay, Novaya Zemlya. The box model developed at NRPA uses a modified approach for compartmental modeling, which takes into account the dispersion of radionuclides over time. The box structures for surface, mid-depth and deep water layers have been developed based on the description of polar, Atlantic and deep waters in the Arctic Ocean and the Northern Seas, as well as site-specific information for the boxes. The volume of the three water layers in each box has been calculated using detailed bathymetry together with Geographical Information Systems. The box model includes the processes of advection of radioactivity between compartments, sedimentation, diffusion of radioactivity through pore water in sediments, resuspension, mixing due to bioturbation, particle mixing and a burial process for radionuclides in deep sediment layers. Radioactive decay is calculated for all compartments. The contamination of biota is further calculated from the known radionuclide concentrations in filtered seawater in the different water regions. Doses to man are calculated on the basis of seafood consumptions, in accordance with available data for seafood catches and assumptions about human diet in the respective areas. Dose to biota are determined on the basis of calculated radionuclide concentrations in marine organisms, water and sediment, using dose conversion factors. Results of the calculations show that atmospheric deposition is the dominant source for the Barents Sea, except for the Chernaya Bay region. It is also demonstrated that the impact of the Sellafield nuclear facilities has

  3. Microscopic modeling of mass and charge distributions in the spontaneous fission of 240Pu

    Science.gov (United States)

    Sadhukhan, Jhilam; Nazarewicz, Witold; Schunck, Nicolas

    2016-01-01

    We propose a methodology to calculate microscopically the mass and charge distributions of spontaneous fission yields. We combine the multidimensional minimization of collective action for fission with stochastic Langevin dynamics to track the relevant fission paths from the ground-state configuration up to scission. The nuclear potential energy and collective inertia governing the tunneling motion are obtained with nuclear density functional theory in the collective space of shape deformations and pairing. We obtain a quantitative agreement with experimental data and find that both the charge and mass distributions in the spontaneous fission of 240Pu are sensitive both to the dissipation in collective motion and to adiabatic fission characteristics.

  4. Microscopic modeling of mass and charge distributions in the spontaneous fission of 240Pu

    CERN Document Server

    Sadhukhan, Jhilam; Schunck, Nicolas

    2016-01-01

    In this letter, we outline a methodology to calculate microscopically mass and charge distributions of spontaneous fission yields. We combine the multi-dimensional minimization of collective action for fission with stochastic Langevin dynamics to track the relevant fission paths from the ground-state configuration up to scission. The nuclear potential energy and collective inertia governing the tunneling motion are obtained with nuclear density functional theory in the collective space of shape deformations and pairing. We obtain a quantitative agreement with experimental data and find that both the charge and mass distributions in the spontaneous fission of 240Pu are sensitive both to the dissipation in collective motion and to adiabatic characteristics.

  5. Annular cylinders experimental programme containing plutonium solutions at different 240Pu contents

    International Nuclear Information System (INIS)

    From 1963 to 1976, 730 critical experiments dealing with annular cylinders containing plutonium nitrate solutions were conducted on Valduc critical facility, called 'Apparatus B'. They aimed at validating critical configurations encountered in the fuel cycle, especially in storage and also at validating the 240Pu cross-sections in thermal neutron spectrum. It is to be noticed that these experiments validate criticality codes either in configurations with reactor-grade plutonium coming from the reprocessing cycle or with weapon-grade plutonium coming from the decommissioning of nuclear weapons. (authors)

  6. Evaluation of 239+240Pu, 137Cs and natural 210Pb fallout in agricultural upland fields in Rokkasho, Japan

    International Nuclear Information System (INIS)

    The background distributions of 239+240Pu and 137Cs fallout in agricultural soil were investigated in Rokkasho where Japan's first commercial nuclear fuel reprocessing plant is now being constructed. The mean inventories of 239+240Pu and 137Cs in three fields with non-yam-cultivation history were 116 Bq x m-2 and 3.4 kBq x m-2, respectively. The mean atomic ratio of 240Pu/239Pu for all studied fields was 0.18±0.04, and was similar to that of global fallout. The 239+240Pu concentrations correlated very well with 137Cs (r = 0.97) in spite of heavy disturbance of the soil, and the activity ratio of 239+240Pu/137Cs was 0.037 ± 0.007, which is a typical value for global fallout. These results showed that the nuclides had similar behavior in agricultural upland fields in Rokkasho. Since 210Pb is steadily deposited from the atmosphere to the land, this nuclide could be an index for the degree of disturbance of a field and of soil lost from the field. The ratio of excess 210Pb inventory in the soil to the equivalent inventory of atmospheric 210Pb deposition was 96%, and indicated that soil was not lost from the cultivated fields. (author)

  7. Transuranic concentrations in reef and pelagic fish from the Marshall Islands. [/sup 239/Pu, /sup 240/Pu

    Energy Technology Data Exchange (ETDEWEB)

    Noshkin, V.E.; Eagle, R.J.; Wong, K.M.; Jokela, T.A.

    1980-09-01

    Concentrations of /sup 239 + 240/Pu are reported in tissues of several species of reef and pelagic fish caught at 14 different atolls in the northern Marshall Islands. Several regularities that are species dependent are evident in the distribution of /sup 239 + 240/Pu among different body tissues. Concentrations in liver always exceeded those in bone and concentrations were lowest in the muscle of all fish analyzed. A progressive discrimination against /sup 239 + 240/Pu was observed at successive trophic levels at all atolls except Bikini and Enewetak, where it was difficult to conclude if any real difference exists between the average concentration factor for /sup 239 + 240/Pu among all fish, which include bottom feeding and grazing herbivores, bottom feeding carnivores, and pelagic carnivores from different atoll locations. The average concentration of /sup 239 + 240/Pu in the muscle of surgeonfish from Bikini and Enewetak was not significantly different from the average concentrations determined in these fish at the other, lesser contaminated atolls. Concentrations among all 3rd, 4th, and 5th trophic level species are highest at Bikini where higher environmental concentrations are found. The reasons for the anomalously low concentrations in herbivores from Bikini and Enewetak are not known.

  8. Alpha-particle emission probabilities in the decay of {sup 240}Pu

    Energy Technology Data Exchange (ETDEWEB)

    Sibbens, G., E-mail: goedele.sibbens@ec.europa.e [European Commission, Joint Research Centre, Institute for Reference Materials and Measurements, Retieseweg 111, B-2440 Geel (Belgium); Pomme, S.; Altzitzoglou, T. [European Commission, Joint Research Centre, Institute for Reference Materials and Measurements, Retieseweg 111, B-2440 Geel (Belgium); Garcia-Torano, E. [Laboratorio de Metrologia de Radiaciones Ionizantes, CIEMAT, Avda. Complutense 22, 28040 Madrid (Spain); Janssen, H.; Dersch, R.; Ott, O. [Physikalisch-Technische Bundesanstalt (PTB), Bundesallee 100, 38116 Braunschweig (Germany); Martin Sanchez, A. [Departamento de Fisica, Universidad de Extremadura, Badajoz, E-06071 (Spain); Rubio Montero, M.P. [Departamento de Fisica Aplicada, Universidad de Extremadura, Merida, Badajoz, E-06800 (Spain); Loidl, M. [Laboratoire National Henri Becquerel, LNE/CEA-LIST, 91191 Gif-sur-Yvette (France); Coron, N.; Marcillac, P. de [Institut d' Astrophysique Spatiale, CNRS, 91405 Orsay Campus (France); Semkow, T.M. [Wadsworth Center, New York State Department of Health, Albany, NY 12201 (United States)

    2010-07-15

    Sources of enriched {sup 240}Pu were prepared by vacuum evaporation on quartz substrates. High-resolution alpha-particle spectrometry of {sup 240}Pu was performed with high statistical accuracy using silicon detectors and with low statistical accuracy using a bolometer. The alpha-particle emission probabilities of six transitions were derived from the spectra and compared with literature values. Additionally, some alpha-particle emission probabilities were derived from {gamma}-ray intensity measurements with a high-purity germanium detector. The alpha-particle emission probabilities of the three main transitions at 5168.1, 5123.6 and 5021.2 keV were derived from seven aggregate spectra analysed with five different fit functions and the results were compatible with evaluated data. Two additional weak peaks at 4863.5 and 4492.0 keV were fitted separately, using the exponential of a polynomial function to represent the underlying tailing of the larger peaks. The peak at 4655 keV could not be detected by alpha-particle spectrometry, while {gamma}-ray spectrometry confirms that its intensity is much lower than expected from literature.

  9. Modeling and production of {sup 240}Am by deuteron-induced activation of a {sup 240}Pu target

    Energy Technology Data Exchange (ETDEWEB)

    Finn, Erin C., E-mail: Erin.Finn@pnnl.gov; McNamara, Bruce, E-mail: Bruce.McNamara@pnnl.gov; Greenwood, Larry, E-mail: Larry.Greenwood@pnnl.gov; Wittman, Richard, E-mail: Richard.Wittman@pnnl.gov; Soderquist, Charles, E-mail: Chuck.Soderquist@pnnl.gov; Woods, Vincent, E-mail: Vincent.Woods@pnnl.gov; VanDevender, Brent, E-mail: Brent.Vandevender@pnnl.gov; Metz, Lori, E-mail: Lori.Metz@pnnl.gov; Friese, Judah, E-mail: Judah.Friese@pnnl.gov

    2015-04-15

    A novel reaction pathway for production of {sup 240}Am is reported. Models of reaction cross-sections in EMPIRE II suggest that deuteron-induced activation of a {sup 240}Pu target produces maximum yields of {sup 240}Am from 11.5 MeV incident deuterons. This activation had not been previously reported in the literature. A {sup 240}Pu target was activated under the modeled optimum conditions to produce {sup 240}Am. The modeled cross-section for the {sup 240}Pu(d, 2n){sup 240}Am reaction is on the order of 20–30 mbarn, but the experimentally estimated value is 5.6 ± 0.2 mbarn. We discuss reasons for the discrepancy as well as production of other Am isotopes that contaminate the final product.

  10. Precision of gamma-ray measurements of the effective specific power and effective {sup 240}Pu fraction of plutonium

    Energy Technology Data Exchange (ETDEWEB)

    Sampson, T.E.

    1992-05-01

    This paper uses gamma-ray spectrometry data from replicate measurements on 40 plutonium-bearing samples to examine the repeatability of the effective {sup 240}Pu fraction ({sup 240}Pu{sub eff}) and the effective specific power (P{sub eff}) calculated from the isotopic distribution analyzed with gamma-ray spectrometry codes. The measurements were used to identify the error component arising from repeatability in the determination of the isotopic composition of plutonium in the sample and the contribution of the error component to the uncertainty in total plutonium mass measurements from neutron coincidence counting ({sup 240}Pu{sub eff}) and calorimetry (P{sub eff}). The 40 samples had {sup 240}Pu{sub eff} percentages ranging from 2 to 39% and P{sub eff} values ranging from 2 to 16 mW/g Pu. Four different gamma-ray spectrometry codes (FRAM, MGA, Blue Box, and PUJRC) were used to analyze the data (not all samples were analyzed with each code). All analyses showed that the % relative standard deviation of P{sub eff} was smaller than that of {sup 240}Pu{sub eff}. This result coupled with a cursory examination of uncertainties in coincidence counting of well-characterized samples and water-bath calorimetry errors for the same types of samples lead to the conclusion that smaller uncertainties will be present in the total plutonium mass determined by the combination of calorimetry/gamma-ray spectrometry than in the mass determined by coincidence counting/gamma-ray spectrometry. An additional examination of the biases arising from the {sup 240}Pu correlation used in the gamma-ray spectrometry codes also supported this conclusion. 17 refs.

  11. ZPR-6 assembly 7 high {sup 240}Pu core experiments : a fast reactor core with mixed (Pu,U)-oxide fuel and a centeral high{sup 240}Pu zone.

    Energy Technology Data Exchange (ETDEWEB)

    Lell, R. M.; Morman, J. A.; Schaefer, R.W.; McKnight, R.D.; Nuclear Engineering Division

    2009-02-23

    ZPR-6 Assembly 7 (ZPR-6/7) encompasses a series of experiments performed at the ZPR-6 facility at Argonne National Laboratory in 1970 and 1971 as part of the Demonstration Reactor Benchmark Program (Reference 1). Assembly 7 simulated a large sodium-cooled LMFBR with mixed oxide fuel, depleted uranium radial and axial blankets, and a core H/D near unity. ZPR-6/7 was designed to test fast reactor physics data and methods, so configurations in the Assembly 7 program were as simple as possible in terms of geometry and composition. ZPR-6/7 had a very uniform core assembled from small plates of depleted uranium, sodium, iron oxide, U{sub 3}O{sub 8} and Pu-U-Mo alloy loaded into stainless steel drawers. The steel drawers were placed in square stainless steel tubes in the two halves of a split table machine. ZPR-6/7 had a simple, symmetric core unit cell whose neutronic characteristics were dominated by plutonium and {sup 238}U. The core was surrounded by thick radial and axial regions of depleted uranium to simulate radial and axial blankets and to isolate the core from the surrounding room. The ZPR-6/7 program encompassed 139 separate core loadings which include the initial approach to critical and all subsequent core loading changes required to perform specific experiments and measurements. In this context a loading refers to a particular configuration of fueled drawers, radial blanket drawers and experimental equipment (if present) in the matrix of steel tubes. Two principal core configurations were established. The uniform core (Loadings 1-84) had a relatively uniform core composition. The high {sup 240}Pu core (Loadings 85-139) was a variant on the uniform core. The plutonium in the Pu-U-Mo fuel plates in the uniform core contains 11% {sup 240}Pu. In the high {sup 240}Pu core, all Pu-U-Mo plates in the inner core region (central 61 matrix locations per half of the split table machine) were replaced by Pu-U-Mo plates containing 27% {sup 240}Pu in the plutonium

  12. The inflow of 238Pu and 239+240Pu from the Vistula River catchment area to the Baltic Sea

    International Nuclear Information System (INIS)

    The aim of the work was to estimate plutonium inflow from the Vistula River's catchments area to the Baltic Sea. There were differences in plutonium activities depending on season and sampling site. The highest activities of 238Pu and 239+240Pu were transported from the Vistula River watershed to the Baltic Sea in spring and the lowest in summer. Annually, the southern Baltic Sea is enriched via the Vistula River with 10.3 MBq of 238Pu and 89.0 MBq of 239+240Pu. The enhanced concentration of plutonium in water from the Vistula River is the result of its runoff from the Vistula drainage area, mostly from snowmelt, enhanced rainfalls and leached materials from river bed. - Highlights: → We estimated plutonium inflow from the Vistula River catchment area to the Baltic Sea. → We found differences in Pu activities depending on season and sampling site. → The highest amount of 239 + 240Pu was transported in spring and the lowest in summer. → Annually, the southern Baltic Sea is enriched with 89.0 MBq of 239 + 240Pu. → Enhanced Pu amount in water came from snowmelt, rainfalls and leached materials.

  13. Measurement and analysis of the $^{243}$Am neutron capture cross section at the n_TOF facility at CERN

    CERN Document Server

    Mendoza, E; Guerrero, C; Berthoumieux, E; Abbondanno, U; Aerts, G; Alvarez-Velarde, F; Andriamonje, S; Andrzejewski, J; Assimakopoulos, P; Audouin, L; Badurek, G; Balibrea, J; Baumann, P; Becvar, F; Belloni, F; Calvino, F; Calviani, M; Capote, R; Carrapico, C; Carrillo de Albornoz, A; Cennini, P; Chepel, V; Chiaveri, E; Colonna, N; Cortes, G; Couture, A; Cox, J; Dahlfors, M; David, S; Dillmann, I; Dolfini, R; Domingo-Pardo, C; Dridi, W; Duran, I; Eleftheriadis, C; Ferrant†, L; Ferrari, A; Ferreira-Marques, R; Fitzpatrick, L; Frais-Koelbl, H; Fujii, K; Furman, W; Goncalves, I; Gonz alez-Romero, E; Goverdovski, A; Gramegna, F; Griesmayer, E; Gunsing, F; Haas, B; Haight, R; Heil, M; Herrera-Martinez, A; Igashira, M; Isaev, S; Jericha, E; Kappeler, F; Kadi, Y; Karadimos, D; Karamanis, D; Ketlerov, V; Kerveno, M; Koehler, P; Konovalov, V; Kossionides, E; Krticka, M; Lampoudis, C; Leeb, H; Lindote, A; Lopes, I; Lossito, R; Lozano, M; Lukic, S; Marganiec, J; Marques, L; Marrone, S; Martınez, T; Massimi, C; Mastinu, P; Mengoni, A; Milazzo, P M; Moreau, C; Mosconi, M; Neves, F; Oberhummer, H; O’Brien, S; Oshima, M; Pancin, J; Papachristodoulou, C; Papadopoulos, C; Paradela, C; Patronis, N; Pavlik, A; Pavlopoulos, P; Perrot, L; Pigni, M T; Plag, R; Plompen, A; Plukis, A; Poch, A; Praena, J; Pretel, C; Quesada, J; Rauscher, T; Reifarth, R; Rosetti, M; Rubbia, C; Rudolf, G; Rullhusen, P; Salgado, J; Santos, C; Sarchiapone, L; Savvidis, I; Stephan, C; Tagliente, G; Tain, J L; Tassan-Got, L; Tavora, L; Terlizzi, R; Vannini, G; Vaz, P; Ventura, A; Villamarin, D; Vicente, M C; Vlachoudis, V; Vlastou, R; Voss, F; Walter, S; Wendler, H; Wiescher, M; Wisshak, K

    2014-01-01

    Background:The design of new nuclear reactors and transmutation devices requires to reduce the present neutron cross section uncertainties of minor actinides. Purpose: Reduce the $^{243}$Am(n,$\\gamma$) cross section uncertainty. Method: The $^{243}$Am(n,$\\gamma$) cross section has been measured at the n_TOF facility at CERN with a BaF$_{2}$ Total Absorption Calorimeter, in the energy range between 0.7 eV and 2.5 keV. Results: The $^{243}$Am(n,$\\gamma$) cross section has been successfully measured in the mentioned energy range. The resolved resonance region has been extended from 250 eV up to 400 eV. In the unresolved resonance region our results are compatible with one of the two incompatible capture data sets available below 2.5 keV. The data available in EXFOR and in the literature has been used to perform a simple analysis above 2.5 keV. Conclusions: The results of this measurement contribute to reduce the $^{243}$Am(n,$\\gamma$) cross section uncertainty and suggest that this cross section is underestimate...

  14. Measurement of fallout radionuclides, (239)(,240)Pu and (137)Cs, in soil and creek sediment: Sydney Basin, Australia.

    Science.gov (United States)

    Smith, B S; Child, D P; Fierro, D; Harrison, J J; Heijnis, H; Hotchkis, M A C; Johansen, M P; Marx, S; Payne, T E; Zawadzki, A

    2016-01-01

    Soil and sediment samples from the Sydney basin were measured to ascertain fallout radionuclide activity concentrations and atom ratios. Caesium-137 ((137)Cs) was measured using gamma spectroscopy, and plutonium isotopes ((239)Pu and (240)Pu) were quantified using accelerator mass spectrometry (AMS). Fallout radionuclide activity concentrations were variable ranging from 0.6 to 26.1 Bq/kg for (137)Cs and 0.02-0.52 Bq/kg for (239+240)Pu. Radionuclides in creek sediment samples were an order of magnitude lower than in soils. (137)Cs and (239+240)Pu activity concentration in soils were well correlated (r(2) = 0.80) although some deviation was observed in samples collected at higher elevations. Soil ratios of (137)Cs/(239+240)Pu (decay corrected to 1/1/2014) ranged from 11.5 to 52.1 (average = 37.0 ± 12.4) and showed more variability than previous studies. (240)Pu/(239)Pu atom ratios ranged from 0.117 to 0.165 with an average of 0.146 (±0.013) and an error weighted mean of 0.138 (±0.001). These ratios are lower than a previously reported ratio for Sydney, and lower than the global average. However, these ratios are similar to those reported for other sites within Australia that are located away from former weapons testing sites and indicate that atom ratio measurements from other parts of the world are unlikely to be applicable to the Australian context.

  15. Measurement of fallout radionuclides, (239)(,240)Pu and (137)Cs, in soil and creek sediment: Sydney Basin, Australia.

    Science.gov (United States)

    Smith, B S; Child, D P; Fierro, D; Harrison, J J; Heijnis, H; Hotchkis, M A C; Johansen, M P; Marx, S; Payne, T E; Zawadzki, A

    2016-01-01

    Soil and sediment samples from the Sydney basin were measured to ascertain fallout radionuclide activity concentrations and atom ratios. Caesium-137 ((137)Cs) was measured using gamma spectroscopy, and plutonium isotopes ((239)Pu and (240)Pu) were quantified using accelerator mass spectrometry (AMS). Fallout radionuclide activity concentrations were variable ranging from 0.6 to 26.1 Bq/kg for (137)Cs and 0.02-0.52 Bq/kg for (239+240)Pu. Radionuclides in creek sediment samples were an order of magnitude lower than in soils. (137)Cs and (239+240)Pu activity concentration in soils were well correlated (r(2) = 0.80) although some deviation was observed in samples collected at higher elevations. Soil ratios of (137)Cs/(239+240)Pu (decay corrected to 1/1/2014) ranged from 11.5 to 52.1 (average = 37.0 ± 12.4) and showed more variability than previous studies. (240)Pu/(239)Pu atom ratios ranged from 0.117 to 0.165 with an average of 0.146 (±0.013) and an error weighted mean of 0.138 (±0.001). These ratios are lower than a previously reported ratio for Sydney, and lower than the global average. However, these ratios are similar to those reported for other sites within Australia that are located away from former weapons testing sites and indicate that atom ratio measurements from other parts of the world are unlikely to be applicable to the Australian context. PMID:26344369

  16. Suitability of 239+240Pu and 137Cs as tracers for soil erosion assessment in mountain grasslands.

    Science.gov (United States)

    Alewell, Christine; Meusburger, Katrin; Juretzko, Gregor; Mabit, Lionel; Ketterer, Michael E

    2014-05-01

    Anthropogenic radionuclides have been distributed globally due to nuclear weapons testing, nuclear accidents, nuclear weapons fabrication, and nuclear fuel reprocessing. While the negative consequences of this radioactive contamination are self-evident, the ubiquitous fallout radionuclides (FRNs) distribution form the basis for the use as tracers in ecological studies, namely for soil erosion assessment. Soil erosion is a major threat to mountain ecosystems worldwide. We compare the suitability of the anthropogenic FRNs, 137Cs and 239+240Pu as soil erosion tracers in two alpine valleys of Switzerland (Urseren Valley, Canton Uri, Central Swiss Alps and Val Piora, Ticino, Southern Alps). We sampled reference and potentially erosive sites in transects along both valleys. 137Cs measurements of soil samples were performed with a Li-drifted Germanium detector and 239+240Pu with ICP-MS. Our data indicates a heterogeneous deposition of the 137Cs, since most of the fallout origins from the Chernobyl April/May 1986 accident, when large parts of the European Alps were still snow-covered. In contrast, 239+240Pu fallout originated mainly from 1950s to 1960s atmospheric nuclear weapons tests, resulting in a more homogenous distribution and thus seems to be a more suitable tracer in mountainous grasslands. Soil erosion assessment using 239+240Pu as a tracer pointed to a huge dynamic and high heterogeneity of erosive processes (between sedimentation of 1.9 and 7 t ha(-1) yr(-1) and erosion of 0.2-16.4 t ha(-1) yr(-1) in the Urseren Valley and sedimentation of 0.4-20.3 t ha(-1) yr(-1) and erosion of 0.1-16.4 t ha(-1) yr(-1) at Val Piora). Our study represents a novel and successful application of 239+240Pu as a tracer of soil erosion in a mountain environment. PMID:24374184

  17. Pion-Induced Fission of 209Bi and 119Sn:. Measurements, Calculations, Analyses and Comparison

    Science.gov (United States)

    Rana, Mukhtar Ahmed; Sher, Gul; Manzoor, Shahid; Shehzad, M. I.

    Cross-sections for the π--induced fission of 209Bi and 119Sn have been measured using the most sensitive CR-39 solid-state nuclear track detector. In experiments, target-detector stacks were exposed to negative pions of energy 500, 672, 1068, and 1665 MeV at the Brookhaven National Laboratory, USA. An important aspect of the present paper is the comparison of pion-induced fission fragment spectra of above mentioned nuclei with the spontaneous fission fragment spectra of 252Cf. This comparison is made in terms of fission fragment track lengths in the CR-39 detectors. Measurement results are compared with calculations of Monte Carlo and statistical weight functions methods using the computer code CEM95. Agreement between measurements and calculations is fairly good for 209Bi target nuclei whereas it is indigent for the case of 119Sn. The possibilities of the trustworthy calculations, using the computer code CEM95, comparable with measurements of pion-induced fission in intermediate and heavy nuclei are explored by employing various systematics available in the code. Energy dependence of pion-induced fission in 119Sn and 209Bi is analyzed employing a newly defined parameter geometric-size-normalized fission cross-section (χfg). It is found that the collective nuclear excitations, which may lead to fission, become more probable for both 209Bi and 119Sn nuclei with increasing energy of negative pions from 500 to 1665 MeV.

  18. Radioecologycal study of {sup 239/240}Pu in Bangka Island and Muria Peninsula: Determination of {sup 239/240}Pu in marine sediment and seawater as part of baseline data collecting for sitting of candidates of first Indonesia NPP

    Energy Technology Data Exchange (ETDEWEB)

    Suseno, Heny, E-mail: henis@batan.go.id [Radioactive Waste Technology Center - The Indonesian National Nuclear Energy Agency (Indonesia); Wisnubroto, Djarot S. [The Indonesian National Nuclear Energy Agency (Indonesia)

    2014-03-24

    Radioisotope Pu-239/240 are alpha emitting nuclides important indicators of radioactive contamination of the marine environment. Global fallout is the main source of plutonium in the marine environment. There are very limited study on {sup 239/240}Pu in Indonesia coastal environments. The data of this radioisotopes is needed for baseline data of nuclear power plant (NPP) site candidates both in Bangka Island and Muria Peninsula. Bottom sediments play an important role in radioecological studies of the marine environment because a large proportion of radioactive substances entering the sea is adsorbed over time onto suspended particulate matter and deposited in sediments. Plutonium is particle reactive and deposited in marine sediment. Radioisotope {sup 239/240}Pu was determinated by alpha spectrometry after radiochemical procedure that was performed in both water and marine sediment from Bangka Island and Muria Peninsula. The sediment baseline of concentration {sup 239/240}Pu in Bangka Island and Muria Peninsula were range from 0.013 to 0.021 Bq.kg{sup −1} and 0.018 to 0.024 Bq.kg{sup −1} respectively. The water baseline concentration this isotope were range from 2.73 to 4.05 mBq.m{sup −3} and 2.98 to 4.50 mBq.m{sup −3}.

  19. Assessment of 238Pu and 239+240Pu, in marine sediments of the oceans Atlantic and Pacific of Guatemala

    International Nuclear Information System (INIS)

    In this investigation samples of marine sediments were taken from 14 places representatives of the oceans coast of Guatemala. For the assesment of 238Pu and 239+240Pu in sediments a radiochemical method was used to mineralize sediments and by ionic interchange it was separated from other elements, after that an electrodeposition of plutonium was made in metallic discs. The radioactivity of plutonium was measured by alpha spectrometry system and the alpha spectrums were obtained. The levels of plutonium are not higher than other countries that shown contamination. The contamination of isotope of 239+240Pu is higher than 238Pu and the contamination by two isotopes of plutonium is higher in the Atlantic than the Pacific ocean

  20. Comparison of evaluations for 235U, 239Pu, 240Pu, 241Pu and 242Pu with integral measurements

    International Nuclear Information System (INIS)

    The evaluations for 235U, 239Pu, 240Pu, 241Pu and 242Pu are considered. Intercomparison is made of the neutron cross section data from INDL/A, ENDL-84, ENDF/B-5 and ENDF/B-6 (where applicable). Integral measurements of the spectrum averaged cross sections are compared to the values derived from evaluated data libraries. (author). 40 refs, 49 figs, 11 tabs

  1. The influence of impurities for cross section measurement of {sup 241,243}Am(n,f) reactions

    Energy Technology Data Exchange (ETDEWEB)

    Kai, Tetsuya; Kobayashi, Katsuhei; Yamamoto, Shuji; Fujita, Yoshiaki; Kimura, Itsuro; Miyoshi, Mitsuharu; Yamamoto, Hideki [Kyoto Univ. (Japan); Shinohara, Nobuo

    1997-03-01

    The influence of the impurities on the fission cross section measurements for {sup 241}Am and {sup 243}Am has been investigated with the practical results. Following cases have been considered as the influence of impurities; (a) experiments with the {sup 241}Am sample that contains impurities originally, and (b) experiments with the {sup 243}Am sample that contains impurities produced by {alpha}, {beta} decays after the chemical purification. The present study has demonstrated the usefulness of pure samples by the comparison of the experiments using the sample on the market with those using the pure sample processed by the authors. Particularly on the case (b), the correction of the impurity through the periodical measurements was experimentally performed (about 18% around 0.3 eV in 4 weeks after the chemical purification). (author)

  2. Distribution and source of 129I, 239,240Pu, 137Cs in the environment of Lithuania

    DEFF Research Database (Denmark)

    Ezerinskis, Z.; Hou, Xiaolin; Druteikiene, R.;

    2016-01-01

    Fifty five soil samples collected in the Lithuania teritory in 2011 and 2012 were analyzed for 129I, 137Cs and Pu isotopes in order to investigate the level and distribution of artificial radioactivity in Lithuania. The activity and atomic ratio of 238Pu/239,240Pu, 129I/127I and 131I/137Cs were...... used to identify the origin of these radionuclides. The 238Pu/239þ240Pu and 240Pu/239Pu ratios in the soil samples analyzed varied in the range of 0.02e0.18 and 0.18e0.24, respectively, suggesting the global fallout as the major source of Pu in Lithuania. The values of 109 to 106 for 129I/127I atomic....... No correlation of the 137Cs and Pu isotopes with 129I was observed, indicating their different sources terms. Results demonstrate uneven distribution of these radionuclides in the Lithuanian territory and several sources of contamination i.e. Chernobyl accident, reprocessing releases and global fallout....

  3. Determination of plutonium isotopes (238Pu, 239Pu, 240Pu, 241Pu) in environmental samples using radiochemical separation combined with radiometric and mass spectrometric measurements

    DEFF Research Database (Denmark)

    Xu, Yihong; Qiao, Jixin; Hou, Xiaolin;

    2014-01-01

    This paper reports an analytical method for the determination of plutonium isotopes (238Pu, 239Pu, 240Pu, 241Pu) in environmental samples using anion exchange chromatography in combination with extraction chromatography for chemical separation of Pu. Both radiometric methods (liquid scintillation......, this is critical for the measurement of plutonium isotopes using mass spectrometric technique. Although the chemical yield of Pu in the entire procedure is about 55%, the analytical results of IAEA soil 6 and IAEA-367 in this work are in a good agreement with the values reported in the literature or reference...... values, revealing that the developed method for plutonium determination in environmental samples is reliable. The measurement results of 239+240Pu by alpha spectrometry agreed very well with the sum of 239Pu and 240Pu measured by ICP-MS. ICP-MS can not only measure 239Pu and 240Pu separately but also 241...

  4. Pu-239 and Pu-240 inventories and Pu-240/ Pu-239 atom ratios in the water column off Sanriku, Japan.

    Science.gov (United States)

    Yamada, Masatoshi; Zheng, Jian; Aono, Tatsuo

    2013-04-01

    A magnitude 9.0 earthquake and subsequent tsunami occurred in the Pacific Ocean off northern Honshu, Japan, on 11 March 2011 which caused severe damage to the Fukushima Dai-ichi Nuclear Power Plant. This accident has resulted in a substantial release of radioactive materials to the atmosphere and ocean, and has caused extensive contamination of the environment. However, no information is available on the amounts of radionuclides such as Pu isotopes released into the ocean at this time. Investigating the background baseline concentration and atom ratio of Pu isotopes in seawater is important for assessment of the possible contamination in the marine environment. Pu-239 (half-life: 24,100 years), Pu-240 (half-life: 6,560 years) and Pu-241 (half-life: 14.325 years) mainly have been released into the environment as the result of atmospheric nuclear weapons testing. The atom ratio of Pu-240/Pu-239 is a powerful fingerprint to identify the sources of Pu in the ocean. The Pu-239 and Pu-240 inventories and Pu-240/Pu-239 atom ratios in seawater samples collected in the western North Pacific off Sanriku before the accident at Fukushima Dai-ichi Nuclear Power Plant will provide useful background baseline data for understanding the process controlling Pu transport and for distinguishing additional Pu sources. Seawater samples were collected with acoustically triggered quadruple PVC sampling bottles during the KH-98-3 cruise of the R/V Hakuho-Maru. The Pu-240/Pu-239 atom ratios were measured with a double-focusing SF-ICP-MS, which was equipped with a guard electrode to eliminate secondary discharge in the plasma and to enhance overall sensitivity. The Pu-239 and Pu-240 concentrations were 2.07 and 1.67 mBq/m3 in the surface water, respectively, and increased with depth; a subsurface maximum was identified at 750 m depth, and the concentrations decreased with depth, then increased at the bottom layer. The total Pu-239+240 inventory in the entire water column (depth interval 0

  5. Characterization of ^{239,240}Pu Radionuclide Adsorption to Soil Particles and Mineral Dust Aerosols

    Science.gov (United States)

    Tatro, D. P.; Arimoto, R.; McMillan, N. J.; Barnes, M.

    2006-12-01

    The release of ^{239,240}Pu into the environment by nuclear weapons testing 50 years ago initiated the cyclic mobilization of Pu-contaminated soil particles via the resuspension of dust resulting in a widespread distribution of Pu and other radionuclides. It is unclear what enables the aeolian transport of Pu in the environment; plausible hypotheses of Pu binding to dust and soil particles include Pu adsorption to iron oxides/hydroxides, organic acids, or silicate minerals such as clays. To investigate the connections between surface soils, dust and radionuclides, samples of soil and/or dust were collected from the Project Gnome Site in Eddy County, NM, the Jemez Mountains near Los Alamos, NM, and two 50-year old attics and wind-blown dust in Big Spring, TX. This study tests the hypothesis that Pu is adsorbed onto Fe oxides and hydroxides that coat dust/soil particles. The samples are generally low in organic carbon (0.2 - 4.8%, except for the unburned Los Alamos sample at 9.4%), as measured by LOI (Loss On Ignition) at 360 °C. The citrate-bicarbonate-dithionite method (CDB) of Fe oxide removal, first proposed by Mehra and Jackson in 1960, was used to selectively extract Fe oxides from the samples while leaving silicate Fe intact. Chemical digestion of each sample creates two fractions, the extracted supernatant and a solid pellet residue. If the Pu were associated with Fe oxides, then Fe and Pu should both be selectively removed from the bulk sample during the CBD process, leaving the pellet depleted in Fe and Pu and the supernatant enriched. For Fe, this was confirmed by scanning electron microscope and petrographic analyses. Preliminary radiochemical analyses of Pu activity also verify this hypothesis. Pu activity is significantly lower in pellets than bulk samples (Pu activitypellet/Pu activitybulk average = 0.07, range 0.02-0.12); Pu activity in supernatants is significantly higher than in bulk samples (Pu activitysupernatant/Pu activitybulk average = 4

  6. Study of neutron-deficient isotopes of Fl in the 239Pu, 240Pu + 48Ca reactions

    Science.gov (United States)

    Voinov, A. A.; Utyonkov, V. K.; Brewer, N. T.; Oganessian, Yu Ts; Rykaczewski, K. P.; Abdullin, F. Sh; Dmitriev, S. N.; Grzywacz, R. K.; Itkis, M. G.; Miernik, K.; Polyakov, A. N.; Roberto, J. B.; Sagaidak, R. N.; Shirokovsky, I. V.; Shumeiko, M. V.; Tsyganov, Yu S.; Subbotin, V. G.; Sukhov, A. M.; Sabelnikov, A. V.; Vostokin, G. K.; Hamilton, J. H.; Stoyer, M. A.; Strauss, S. Y.

    2016-07-01

    The results of the experiments aimed at the synthesis of Fl isotopes in the 239Pu + 48Ca and 240Pu + 48Ca reactions are presented. The experiment was performed using the Dubna gas-filled recoil separator at the U400 cyclotron. In the 239Pu+48Ca experiment one decay of spontaneously fissioning 284Fl was detected at 245-MeV beam energy. In the 240Pu+48Ca experiment three decay chains of 285Fl were detected at 245 MeV and four decays were assigned to 284Fl at the higher 48Ca beam energy of 250 MeV. The α-decay energy of 285Fl was measured for the first time and decay properties of its descendants 281Cn, 277Ds, 273Hs, 269Sg, and 265Rf were determined more precisely. The cross section of the 239Pu(48Ca,3n)284Fl reaction was observed to be about 20 times lower than those predicted by theoretical models and 50 times less than the value measured in the 244Pu+48Ca reaction. The cross sections of the 240Pu(48Ca,4-3n)284,285Fl at both 48Ca energies are similar and exceed that observed in the reaction with lighter isotope 239Pu by a factor of 10. The decay properties of the synthesized nuclei and their production cross sections indicate rapid decrease of stability of superheavy nuclei with departing from the neutron number N=184 predicted to be the next magic number.

  7. Precision laser spectroscopy of the ground state hyperfine splitting of hydrogenlike ^209 Bi^82+

    OpenAIRE

    Klaft, Ingo; Borneis, Stefan; Engel, Thomas; Fricke, Burkhard; Grieser, Ralf; HUBER, GERHARD; Kühl, Thomas; Marx, Dieter; Neumann, Reinhard; Schröder, Sönke; Seelig, Peter; Völker, Lothar

    1994-01-01

    The first direct observation of a hyperfine splitting in the optical regime is reported. The wavelength of the M1 transition between the F = 4 and F = 5 hyperfine levels of the ground state of hydrogenlike ^209 Bi^82+ was measured to be \\lamda_0 = 243.87(4) nm by detection of laser induced fluorescence at the heavy-ion storage ring ESR at GSI. In addition, the lifetime of the laser excited F = 5 sublevel was determined to be \\tau_0 = 0.351(16) ms. The method can be applied to a number of othe...

  8. Migration of 137Cs, 90Sr, and 239+240Pu in Mediterranean forests: influence of bioavailability and association with organic acids in soil

    International Nuclear Information System (INIS)

    The understanding of downward migration of anthropogenic radionuclides in soil is a key factor in the assessment of their environmental behavior. There are several factors that can affect this process, such as the radionuclide source, their chemical form, soil and environmental characteristics, etc. Two Mediterranean pinewood ecosystems in Spain, which were affected mainly by global fallout, were selected to assess the migration of 137Cs, 90Sr, and 239+240Pu. Using auxiliary modeling (diffusion–convection equation and compartmental model), it followed from field observations that the migration velocities of 90Sr and 239+240Pu were similar and higher than that of 137Cs. The downward migration of radionuclides can be considered a consequence of their association with soil particles. A sequential speciation procedure also confirmed that 90Sr was the most bioavailable radionuclide followed by 239+240Pu and 137Cs. Although this can explain the different velocity of 90Sr and 137Cs, bioavailability could not explain by itself the similar velocities of 239+240Pu and 90Sr. The presence of organic acids in the soil can also influence the migration of radionuclides attached to them, which decreased in the order: 239+240Pu > 90Sr > 137Cs. Thus, the joint consideration of bioavailable and humic + fulvic acid fractions can explain the observed differences in the downward velocities. - Highlights: • Downward migration velocities of 137Cs, 90Sr and 239+240Pu in two Mediterranean forests were determined. • Downward migration velocities: 90Sr ≈ 239+240Pu > 137Cs. • Bioavailability by itself (90Sr > 239+240Pu > 137Cs) does not explain differences in migration velocities. • Humic + Fulvic acids: 239+240Pu > 90Sr > 137Cs. • Humic + Fulvic acids and bioavailable fraction can explain the downward migration velocities

  9. Migration of (137)Cs, (90)Sr, and (239+240)Pu in Mediterranean forests: influence of bioavailability and association with organic acids in soil.

    Science.gov (United States)

    Guillén, J; Baeza, A; Corbacho, J A; Muñoz-Muñoz, J G

    2015-06-01

    The understanding of downward migration of anthropogenic radionuclides in soil is a key factor in the assessment of their environmental behavior. There are several factors that can affect this process, such as the radionuclide source, their chemical form, soil and environmental characteristics, etc. Two Mediterranean pinewood ecosystems in Spain, which were affected mainly by global fallout, were selected to assess the migration of (137)Cs, (90)Sr, and (239+240)Pu. Using auxiliary modeling (diffusion-convection equation and compartmental model), it followed from field observations that the migration velocities of (90)Sr and (239+240)Pu were similar and higher than that of (137)Cs. The downward migration of radionuclides can be considered a consequence of their association with soil particles. A sequential speciation procedure also confirmed that (90)Sr was the most bioavailable radionuclide followed by (239+240)Pu and (137)Cs. Although this can explain the different velocity of (90)Sr and (137)Cs, bioavailability could not explain by itself the similar velocities of (239+240)Pu and (90)Sr. The presence of organic acids in the soil can also influence the migration of radionuclides attached to them, which decreased in the order: (239+240)Pu > (90)Sr > (137)Cs. Thus, the joint consideration of bioavailable and humic + fulvic acid fractions can explain the observed differences in the downward velocities.

  10. Distribution and source of (129)I, (239)(,240)Pu, (137)Cs in the environment of Lithuania.

    Science.gov (United States)

    Ežerinskis, Ž; Hou, X L; Druteikienė, R; Puzas, A; Šapolaitė, J; Gvozdaitė, R; Gudelis, A; Buivydas, Š; Remeikis, V

    2016-01-01

    Fifty five soil samples collected in the Lithuania teritory in 2011 and 2012 were analyzed for (129)I, (137)Cs and Pu isotopes in order to investigate the level and distribution of artificial radioactivity in Lithuania. The activity and atomic ratio of (238)Pu/((239,24)0)Pu, (129)I/(127)I and (131)I/(137)Cs were used to identify the origin of these radionuclides. The (238)Pu/(239+240)Pu and (240)Pu/(239)Pu ratios in the soil samples analyzed varied in the range of 0.02-0.18 and 0.18-0.24, respectively, suggesting the global fallout as the major source of Pu in Lithuania. The values of 10(-9) to 10(-6) for (129)I/(127)I atomic ratio revealed that the source of (129)I in Lithuania is global fallout in most cases though several sampling sites shows a possible impact of reprocessing releases. Estimated (129)I/(131)I ratio in soil samples from the southern part of Lithuania shows negligible input of the Chernobyl fallout. No correlation of the (137)Cs and Pu isotopes with (129)I was observed, indicating their different sources terms. Results demonstrate uneven distribution of these radionuclides in the Lithuanian territory and several sources of contamination i.e. Chernobyl accident, reprocessing releases and global fallout. PMID:26476410

  11. Distribution and source of (129)I, (239)(,240)Pu, (137)Cs in the environment of Lithuania.

    Science.gov (United States)

    Ežerinskis, Ž; Hou, X L; Druteikienė, R; Puzas, A; Šapolaitė, J; Gvozdaitė, R; Gudelis, A; Buivydas, Š; Remeikis, V

    2016-01-01

    Fifty five soil samples collected in the Lithuania teritory in 2011 and 2012 were analyzed for (129)I, (137)Cs and Pu isotopes in order to investigate the level and distribution of artificial radioactivity in Lithuania. The activity and atomic ratio of (238)Pu/((239,24)0)Pu, (129)I/(127)I and (131)I/(137)Cs were used to identify the origin of these radionuclides. The (238)Pu/(239+240)Pu and (240)Pu/(239)Pu ratios in the soil samples analyzed varied in the range of 0.02-0.18 and 0.18-0.24, respectively, suggesting the global fallout as the major source of Pu in Lithuania. The values of 10(-9) to 10(-6) for (129)I/(127)I atomic ratio revealed that the source of (129)I in Lithuania is global fallout in most cases though several sampling sites shows a possible impact of reprocessing releases. Estimated (129)I/(131)I ratio in soil samples from the southern part of Lithuania shows negligible input of the Chernobyl fallout. No correlation of the (137)Cs and Pu isotopes with (129)I was observed, indicating their different sources terms. Results demonstrate uneven distribution of these radionuclides in the Lithuanian territory and several sources of contamination i.e. Chernobyl accident, reprocessing releases and global fallout.

  12. A modelling study on {sup 137}Cs and {sup 239,240}Pu behaviour in the Alboran Sea, western Mediterranean

    Energy Technology Data Exchange (ETDEWEB)

    Perianez, R. [Departamento Fisica Aplicada I, E.U. Ingenieria Tecnica Agricola, Universidad de Sevilla, Ctra., Utrera km 1, 41013 Sevilla (Spain)], E-mail: rperianez@us.es

    2008-04-15

    A model for simulating the dispersion processes of {sup 137}Cs and {sup 239,240}Pu in the Alboran Sea is described. The model consists of two hydrodynamic models: a 2D depth-averaged model and a two-layer model which provide tidal and geostrophic currents, respectively; a sediment transport model which provides suspended particle concentrations and sedimentation rates over the domain; and the radionuclide dispersion model including interactions of dissolved radionuclides with suspended particles and bed sediments. These processes are formulated using kinetic transfer coefficients. The hydrodynamic and sediment models are run and validated in advance, and their results are then used to simulate the dispersion of {sup 137}Cs and {sup 239,240}Pu, which are introduced from atmospheric fallout. Radionuclide concentrations in the water column and distributions in bed sediments have been compared with measurements in the sea. Both set of data are, in general, in agreement. The model has also been applied to calculate radionuclide fluxes through the Strait of Gibraltar. These computed fluxes have been compared with previous estimations as well.

  13. Coulomb breakup effects on the elastic cross section of $^6$He+$^{209}$Bi scattering near Coulomb barrier energies

    CERN Document Server

    Matsumoto, T; Iseri, Y; Kamimura, M; Ogata, K; Yahiro, M

    2006-01-01

    We accurately analyze the $^6$He+$^{209}$Bi scattering at 19 and 22.5 MeV near the Coulomb barrier energy, using the continuum-discretized coupled-channels method (CDCC) based on the $n$+$n$+$^4$He+$^{209}$Bi four-body model. The three-body breakup continuum of $^6$He is discretized by diagonalizing the internal Hamiltonian of $^6$He in a space spanned by the Gaussian basis functions. The calculated elastic and total reaction cross sections are in good agreement with the experimental data, while the CDCC calculation based on the di-neutron model of $^6$He, i.e., the $^2n$+$^{4}$He+$^{209}$Bi three-body model, does not reproduce the data.

  14. Pertubation in the 240Pu/239Pu global fallout ratio in local sediments following the nuclear accidents at Thule (Greenland) and Palomares (Spain)

    DEFF Research Database (Denmark)

    Mitchell, P.I.; León Vintró, L.; Dahlgaard, H.;

    1997-01-01

    It is well established that the main source of the plutonium found in marinesediments throughout the Northern Hemisphere is global stratospheric fallout, characterized by a typical Pu-240/Pu-239 atom ratio of similar to 0.18. Measurement of perturbations in this ratio at various sites which had...... been subjected to close-in fallout, mainly from surface-based testing (e.g. Bikini Atoll, Nevada test site, Mururoa Atoll), has confirmed the feasibility of using this ratio to distinguish plutonium from different fallout sources. In the present study, the Pu-240/Pu-239 ratio has been examined...... in samples of sediment (and soil) collected at Thule (Greenland) and Palomares (Spain), where accidents involving the release and dispersion of plutonium from fractured nuclear weapons occurred in 1968 and 1966, respectively. The Pu-240/Pu-239 ratio was measured by high-resolution alpha spectrometry...

  15. Measurement of the fission cross-section of $^{240}$Pu and $^{242}$Pu at CERN's n_TOF Facility

    CERN Multimedia

    Pavlik, A F; Gonzalez romero, E M

    The n_TOF Collaboration proposes to continue the fission program, already started in 2002-2004, taking advantage of the newly constructed Work Sector Type A, with the measurement of the two isotopes : $^{240}$ Pu and $^{242}$ Pu. They are both of major importance for reactor physics applications and are included in the Nuclear Energy Agency (NEA) High Priority List [1], in the NEA WPEC Subgroup 26 Report on the accuracy of nuclear data for advanced reactor designe [2] and in the EU 6$^{th}$ Framework Programme IP-EUROTRANS/NUDATRA reports [3]. Based on those requests, the measurement of the fission cross-section of the two Pu isotopes is one of the objectives of the project ANDES of the FP7 EURATOM program [4].

  16. Polonium 210Po, uranium (234U, 238U and plutonium (238Pu, 239+240Pu bioaccumulation in marine birds

    Directory of Open Access Journals (Sweden)

    Strumińska-Parulska D. I.

    2013-04-01

    Full Text Available The aim of this work was the determination of 210Po, 234U, 238U, 238Pu and 239+240Pu concentration in marine birds which permanently or temporally live in the southern Baltic Sea coast. We chose 11 species of seabirds: three species permanently residing at southern Baltic Sea, four species of wintering birds and three species of migrating birds. The results show that analyzed radionuclides are non-uniformly distributed in the marine birds. The highest activities of 210Po were observed in feathers, muscles and liver. The highest uranium content was found in liver, rest of viscera and feathers, while plutonium in the digestion organs and feathers. Omnivore seabirds accumulated more polonium, plutonium than species that feed on fish, while herbivore seabirds accumulated more uranium than carnivore.

  17. References to Studies of 137Cs, 90Sr and 239+240Pu in the Pacific Ocean a Bibliography

    Energy Technology Data Exchange (ETDEWEB)

    Noshkin, V.E.

    2001-02-01

    This report contains a listing of publications known to this author on reported concentrations, reviews and discussions of {sup 137}Cs, {sup 90}Sr and {sup 239+240}Pu in seawater, sediment and the biota from parts of the North and South Pacific Ocean. Each reference has been assigned an accession number consisting of the first three letters of the first author's last name followed by the first letter of the first name, the year of the publication and an assigned number. Studies in both the coastal areas and the open ocean are included as well as those providing data within lagoons of coral atolls. Some references to the radionuclides in the Indian Ocean are also provided.

  18. Bioturbation depths, rates and processes in Massachusetts Bay sediments inferred from modeling of 210Pb and 239 + 240Pu profiles

    Science.gov (United States)

    Crusius, John; Bothner, Michael H.; Sommerfield, Christopher K.

    2004-01-01

    Profiles of 210Pb and 239 + Pu from sediment cores collected throughout Massachusetts Bay (water depths of 36-192 m) are interpreted with the aid of a numerical sediment-mixing model to infer bioturbation depths, rates and processes. The nuclide data suggest extensive bioturbation to depths of 25-35 cm. Roughly half the cores have 210Pb and 239 + 240Pu profiles that decrease monotonically from the surface and are consistent with biodiffusive mixing. Bioturbation rates are reasonably well constrained by these profiles and vary from ~0.7 to ~40 cm2 yr-1. As a result of this extensive reworking, however, sediment ages cannot be accurately determined from these radionuclides and only upper limits on sedimentation rates (of ~0.3 cm yr-1) can be inferred. The other half of the radionuclide profiles are characterized by subsurface maxima in each nuclide, which cannot be reproduced by biodiffusive mixing models. A numerical model is used to demonstrate that mixing caused by organisms that feed at the sediment surface and defecate below the surface can cause the subsurface maxima, as suggested by previous work. The deep penetration depths of excess 210Pb and 239 + 240Pu suggest either that the organisms release material over a range of >15 cm depth or that biodiffusive mixing mediated by other organisms is occurring at depth. Additional constraints from surficial sediment 234Th data suggest that in this half of the cores, the vast majority of the present-day flux of recent, nuclide-bearing material to these core sites is transported over a timescale of a month or more to a depth of a few centimeters below the sediment surface. As a consequence of the complex mixing processes, surface sediments include material spanning a range of ages and will not accurately record recent changes in contaminant deposition.

  19. Measurements of high-energy neutron-induced fission ofnatPb and 209Bi

    Directory of Open Access Journals (Sweden)

    Couture A.

    2010-10-01

    Full Text Available The CERN Neutron Time-Of-Flight (n_TOF facility is well suited to measure low cross sections as those of neutron-induced fission in subactinides. The cross section ratios of natPb and 209Bi relative to 235U and 238U were measured using PPAC detectors and a fragment coincidence method that allows us to identify the fission events. The present experiment provides first results for neutron-induced fission up to 1 GeV. Good agreement is found with previous experimental data below 200 MeV. The comparison with proton-induced fission indicates that the limiting regime where neutron-induced and proton-induced fission reach equal cross sections is close to 1 GeV.

  20. Deposition of [sup 210]Pb, [sup 137]Cs, [sup 239+240]Pu, [sup 238]Pu, and [sup 241]Am in the Antarctic peninsula area

    Energy Technology Data Exchange (ETDEWEB)

    Roos, P.; Holm, E.; Persson, R.B.R. (Lund Univ. (Sweden). Dept. of Radiation Physics); Aarkrog, A.; Nielsen, S.P. (Risoe National Lab., Roskilde (Denmark))

    1994-01-01

    [sup 210]Pb, [sup 137]Cs, [sup 239+240]Pu, [sup 238]Pu, and [sup 241]Am were analysed in lichen, moss, grass and soil samples, as well as in lake sediments, from the South Shetland Islands, the Antarctic, in order to evaluate the flux and deposition of these elements. Average inventories of the analysed radionuclides in 1988 are given. The ratios [sup 238]Pu/[sup 239+240]Pu and [sup 241]Am/[sup 239+240]Pu of 0.21 [+-] 0.04 and 0.35 [+-] 0.08 respectively agree well with expected values in this area. A significant difference in [sup 137]Cs/[sup 239+240]Pu ratios between lichens and moss/grass/soil is observed which may be an effect of submerging and melt water altering radionuclide ratios. From one of three lakes studied it is possible to perform [sup 210]Pb dating with reasonable accuracy showing an average annual sediment accumulation in this lake of about 45 g m[sup -2]. (author).

  1. Perturbation in the 240Pu/239Pu global fallout ratio in local sediment following the nuclear accidents at Thule (Greenland) and Palomares (Spain)

    International Nuclear Information System (INIS)

    It is well established that the main source of the plutonium found in marine sediments throughout the Northern Hemisphere is global stratospheric fallout, characterized by a typical 240Pu/239Pu atom ratio of ∼0.18. Measurements of perturbations in this ratio at various sites which had been subjected to close-in fallout, mainly from surface-based testing, has confirmed the feasibility of using this ratio to distinguish plutonium from different fallout sources. In the present study, the 240Pu/239Pu ratio has been examined in samples of sediment collected at Thule (Greenland) and Palomares (Spain), where accidents involving the release and dispersion of plutonium from fractured nuclear weapons occurred in 1968 and 1966, respectively. The 240Pu/239Pu ratio was measured by high-resolution alpha spectrometry and spectral deconvolution. The analytical results showed that at Thule the mean 240Pu/239Pu atom ratio was 0.033±0.004, while at Palomares the equivalent ratio appeared to be significantly higher at 0.056±0.003. Both ratios are consistent with those reported for soils samples at the Nevada site and Nagasaki, and are clearly indicative of weapons-grade plutonium. 27 refs., 1 fig., 2 tabs

  2. Determination of plutonium isotopes (238Pu, 239Pu, 240Pu, 241Pu) in environmental samples using radiochemical separation combined with radiometric and mass spectrometric measurements.

    Science.gov (United States)

    Xu, Yihong; Qiao, Jixin; Hou, Xiaolin; Pan, Shaoming; Roos, Per

    2014-02-01

    This paper reports an analytical method for the determination of plutonium isotopes ((238)Pu, (239)Pu, (240)Pu, (241)Pu) in environmental samples using anion exchange chromatography in combination with extraction chromatography for chemical separation of Pu. Both radiometric methods (liquid scintillation counting and alpha spectrometry) and inductively coupled plasma mass spectrometry (ICP-MS) were applied for the measurement of plutonium isotopes. The decontamination factors for uranium were significantly improved up to 7.5 × 10(5) for 20 g soil compared to the level reported in the literature, this is critical for the measurement of plutonium isotopes using mass spectrometric technique. Although the chemical yield of Pu in the entire procedure is about 55%, the analytical results of IAEA soil 6 and IAEA-367 in this work are in a good agreement with the values reported in the literature or reference values, revealing that the developed method for plutonium determination in environmental samples is reliable. The measurement results of (239+240)Pu by alpha spectrometry agreed very well with the sum of (239)Pu and (240)Pu measured by ICP-MS. ICP-MS can not only measure (239)Pu and (240)Pu separately but also (241)Pu. However, it is impossible to measure (238)Pu using ICP-MS in environmental samples even a decontamination factor as high as 10(6) for uranium was obtained by chemical separation. PMID:24401459

  3. Speciation analysis of 129I, 137Cs, 232Th, 238U, 239Pu and 240Pu in environmental soil and sediment

    DEFF Research Database (Denmark)

    Qiao, Jixin; Hansen, Violeta; Hou, Xiaolin;

    2012-01-01

    The environmental mobility and bioavailability of radionuclides are related to their physicochemical forms, namely species. We here present a speciation analysis of important radionuclides including 129I (also 127I), 137Cs, 232Th, 238U and plutonium isotopes (239Pu and 240Pu) in soil (IAEA-375...

  4. Determination of plutonium isotopes (238Pu, 239Pu, 240Pu, 241Pu) in environmental samples using radiochemical separation combined with radiometric and mass spectrometric measurements.

    Science.gov (United States)

    Xu, Yihong; Qiao, Jixin; Hou, Xiaolin; Pan, Shaoming; Roos, Per

    2014-02-01

    This paper reports an analytical method for the determination of plutonium isotopes ((238)Pu, (239)Pu, (240)Pu, (241)Pu) in environmental samples using anion exchange chromatography in combination with extraction chromatography for chemical separation of Pu. Both radiometric methods (liquid scintillation counting and alpha spectrometry) and inductively coupled plasma mass spectrometry (ICP-MS) were applied for the measurement of plutonium isotopes. The decontamination factors for uranium were significantly improved up to 7.5 × 10(5) for 20 g soil compared to the level reported in the literature, this is critical for the measurement of plutonium isotopes using mass spectrometric technique. Although the chemical yield of Pu in the entire procedure is about 55%, the analytical results of IAEA soil 6 and IAEA-367 in this work are in a good agreement with the values reported in the literature or reference values, revealing that the developed method for plutonium determination in environmental samples is reliable. The measurement results of (239+240)Pu by alpha spectrometry agreed very well with the sum of (239)Pu and (240)Pu measured by ICP-MS. ICP-MS can not only measure (239)Pu and (240)Pu separately but also (241)Pu. However, it is impossible to measure (238)Pu using ICP-MS in environmental samples even a decontamination factor as high as 10(6) for uranium was obtained by chemical separation.

  5. 137Cs, 239,240Pu and 241Am in boreal forest soil and their transfer into wild mushrooms and berries

    International Nuclear Information System (INIS)

    Profiles of podzolic soil from boreal forests were sampled from eight sites in Finland and the distribution of 137Cs in the soil layers was determined. In addition, 239,240Pu and 241Am were determined from two soil profiles taken at one sampling site. Inventories of 137Cs in the soil profiles varied between 1.7 kBq/m2 and 42 kBq/m2, reflecting known variation in 137Cs fallout from the Chernobyl accident. The highest proportions of the radionuclides were found in the organic layer at a depth of less than 5 cm, which on average contained 47% of 137Cs, 76% of 239,240Pu and 79% of 241Am. In the litter, clearly higher proportions of 137Cs were found compared to 239,240Pu and 241Am, probably indicating its more effective recycling from the organic layer back to the surface. Only very minor proportions of 137Cs were recorded below 20 cm. The concentration of 137Cs in the soil profiles could be approximated with a declining logarithmic trend. The activity concentrations of 137Cs were determined for six wild mushroom species and three wild berry species at two sites, as well as the aggregated transfer factors and the distribution of 137Cs between their various parts. In addition, 239,240Pu and 241Am were determined in one mushroom and three berry species at one site. Very high concentrations of 137Cs, up to 20 kBq/kg (d.w.), were found in mushrooms, and their transfer factors were between 0.1 m2/kg and 1.0 m2/kg. In berries, the transfer factors were an order of magnitude lower. 137Cs accumulated more in the caps of mushrooms and in the fruits of berries than in other parts. Transfer factors for 239,240Pu and 241Am were two to three orders of magnitude lower than those of 137Cs. - Highlights: ► 137Cs, 239,240Pu and 241Am mainly concentrated in organic layer in podzolic soil. ► Distribution of 137Cs in the upper 20 cm soil follows exponential declining trend. ► 137Cs concentrates into mushrooms but varies considerably between species. ► 137Cs concentrates in mushroom

  6. Using 239+240Pu atmospheric deposition and a simplified mass-balance model to re-estimate the soil erosion rate. A case study of Liaodong Bay in China

    International Nuclear Information System (INIS)

    By using the mass balance model of 137Cs and introducing 239+240Pu atmospheric deposition, a simplified mass balance model of 239+240Pu was developed and the soil erosion rate was re-estimated. The results indicated that the reference inventory of 239+240Pu was estimated to be 88.4 Bq/m2 in Liaodong Bay. In addition, the atomic ratios of 240Pu/239Pu in all core samples were approximately 0.18, which indicated that the major source of Pu was the global fallout. Statistical analysis of the erosion rates derived from the model demonstrates that the 239+240Pu atmospheric deposition is a feasible way to estimate the soil erosion rate and further improve tracer technique to assess the soil erosion rate. (author)

  7. Plutonium concentration and (240)Pu/(239)Pu atom ratio in biota collected from Amchitka Island, Alaska: recent measurements using ICP-SFMS.

    Science.gov (United States)

    Bu, Kaixuan; Cizdziel, James V; Dasher, Douglas

    2013-10-01

    Three underground nuclear tests, including the Unites States' largest, were conducted on Amchitka Island, Alaska. Monitoring of the radiological environment around the island is challenging because of its remote location. In 2008, the Department of Energy (DOE) Office of Legacy Management (LM) became responsible for the long term maintenance and surveillance of the Amchitka site. The first DOE LM environmental survey occurred in 2011 and is part of a cycle of activities that will occur every 5 years. The University of Alaska Fairbanks, a participant in the 2011 study, provided the lichen (Cladonia spp.), freshwater moss (Fontinalis neomexicanus), kelp (Eualaria fistulosa) and horse mussel (Modiolus modiolus) samples from Amchitka Island and Adak Island (a control site). These samples were analyzed for (239)Pu and (240)Pu concentration and (240)Pu/(239)Pu atom ratio using inductively coupled plasma sector field mass spectrometry (ICP-SFMS). Plutonium concentrations and (240)Pu/(239)Pu atom ratios were generally consistent with previous terrestrial and marine studies in the region. The ((239)+)(240)Pu levels (mBq kg(-1), dry weight) ranged from 3.79 to 57.1 for lichen, 167-700 for kelp, 27.9-148 for horse mussel, and 560-573 for moss. Lichen from Adak Island had higher Pu concentrations than Amchitka Island, the difference was likely the result of the higher precipitation at Adak compared to Amchitka. The (240)Pu/(239)Pu atom ratios were significantly higher in marine samples compared to terrestrial and freshwater samples (t-test, p Pu occurred into the North Pacific Ocean, likely from the Marshall Island high yield nuclear tests, but other potential sources, such as the Kamchatka Peninsula Rybachiy Naval Base and Amchitka Island underground nuclear test site cannot be ruled out.

  8. Transference of particles in the fusion process of {sup 6}He + {sup 209}Bi; Transferencia de particulas en el proceso de fusion de {sup 6}He + {sup 209}Bi

    Energy Technology Data Exchange (ETDEWEB)

    Lizcano, D.; Aguilera, E.F.; Martinez Q, E. [Instituto Nacional de Investigaciones Nucleares, A.P. 18-1027, 11801 Mexico D.F. (Mexico)

    2000-07-01

    In a recent work were reported measurements done to energy which was to the Coulomb barrier for the {sup 6} He + {sup 209} Bi system. The fusion excitation function measured for this system shows a strong enhancement with respect to the predictions of the penetration model of unidimensional barrier at minor energies to the Coulombian barrier. In basis with the results obtained for different degrees of freedom it was determined with the CCDEF code, that the transfer of 2 neutrons of {sup 6} He to binding states to {sup 209} Bi, producing {sup 211} Bi, is the mechanism looked as the best candidate for explain the great enhancement in the fusion excitation function of this system at energies under Coulomb barrier. It is corroborated what was affirmed by others authors about the strength value at 1.5 MeV as a typical value for the transference of two particles between the projectile and the target. (Author)

  9. Preliminary results on ^241,243Am and ^235U (n,γ) cross sections measured at DANCE

    Science.gov (United States)

    Jandel, M.; Bredeweg, T. A.; Fowler, M. M.; Bond, E. M.; O'Donnell, J. M.; Reifarth, R.; Rundberg, R. S.; Ullmann, J. L.; Vieira, D. J.; Wilhelmy, J. B.; Wouters, J. M.; Macri, R. A.; Wu, C.-Y.; Becker, J. A.

    2006-10-01

    The Detector for Advanced Neutron Capture Experiments (DANCE) at Los Alamos National Laboratory (LANL) was used for neutron capture cross sections measurements. Its high granularity of 160 BaF2 detectors allows for highly efficient detection of prompt gamma-rays following a neutron capture. DANCE is located on the 20.26 m neutron flight path 14 at the Manuel Lujan Jr. Neutron Scattering Center at the Los Alamos Neutron Science Center (LANSCE). The moderated production target provides neutrons in the 0.02 eV - 500 keV energy range. An analysis of neutron capture measurements on ^241,243Am and ^235U targets will be presented. The experiments were carried out using a customized Parallel-Plate Avalanche Counter (PPAC) detector installed in the center of the DANCE array. The PPAC was used as a fission-tagging detector to separate (n,γ) from (n,fission) events. Preliminary results of (n,γ) cross sections will be presented and compared with the available evaluated data for neutron energies from 0.02 eV to 1 keV. Additional neutron capture measurements with DANCE will be briefly discussed.

  10. Neutron capture cross section measurements of $^{238}$U, $^{241}$Am and $^{243}$Am at n_TOF

    CERN Multimedia

    Koehler, P E; Plag, R

    The increase of the world energy demand and the need of low carbon energy sources have triggered the renaissance and/or enhancement of nuclear energy in many countries. Fundamental nuclear physics can contribute in a practical way to the sustainability and safety of the nuclear energy production and the management of the nuclear waste. There exists a series of recent studies which address the most relevant isotopes, decay data, nuclear reaction channels and energy ranges which have to be investigated in more detail for improving the design of different advanced nuclear systems [1] and nuclear fuel cycles [2]. In this proposal, we aim at the measurement of the neutron capture cross sections of $^{238}$U, $^{241}$Am and $^{243}$Am. All three isotopes are listed in the NEA High Priority Request List [37], are recommended for measurements [1] and play an important role in the nuclear energy production and fuel cycle scenarios. The measurements will provide as well valuable nuclear structure data necessary for the...

  11. Simultaneous description of CF, ICF and TF data of 6,7Li + 209Bi reaction using new ICF mode

    International Nuclear Information System (INIS)

    The systematic behavior of the fusion suppression factors and ICF probability as a function of target mass is not well understood, despite the CF experimental data being available for a number of projectile-target systems. In our recent paper, a new method was proposed to calculate the ICF probability which is based on absorption cross sections obtained from the CDCC calculations. In continuation of this work, we have also carried out similar calculations for 6,7Li + 209Bi where the experimental data of CF and ICF is available. In the recent paper by Marta et al., the semi-classical model calculations were attempted to understand CF and ICF data for 6,7Li + 209Bi, which was not explaining the data quite well. Here, we have demonstrated the use of quantum mechanical treatment for simultaneous explanation of CF, ICF and TF over a large energy range

  12. (236)U and (239,)(240)Pu ratios from soils around an Australian nuclear weapons test site.

    Science.gov (United States)

    Tims, S G; Froehlich, M B; Fifield, L K; Wallner, A; De Cesare, M

    2016-01-01

    The isotopes (236)U, (239)Pu and (240)Pu are present in surface soils as a result of global fallout from nuclear weapons tests carried out in the 1950's and 1960's. These isotopes potentially constitute artificial tracers of recent soil erosion and sediment movement. Only Accelerator Mass Spectrometry has the requisite sensitivity to measure all three isotopes at these environmental levels. Coupled with its relatively high throughput capabilities, this makes it feasible to conduct studies of erosion across the geographical extent of the Australian continent. In the Australian context, however, global fallout is not the only source of these isotopes. As part of its weapons development program the United Kingdom carried out a series of atmospheric and surface nuclear weapons tests at Maralinga, South Australia in 1956 and 1957. The tests have made a significant contribution to the Pu isotopic abundances present in the region around Maralinga and out to distances ∼1000 km, and impact on the assessment techniques used in the soil and sediment tracer studies. Quantification of the relative fallout contribution derived from detonations at Maralinga is complicated owing to significant contamination around the test site from numerous nuclear weapons safety trials that were also carried out around the site. We show that (236)U can provide new information on the component of the fallout that is derived from the local nuclear weapons tests, and highlight the potential of (236)U as a new fallout tracer.

  13. Determination of 90Sr, 137Cs and (239+240)Pu in waters with use of preliminary concentration

    International Nuclear Information System (INIS)

    A method for the simultaneous determination of artificial radionuclides (90Sr, 137Cs and (239+240)Pu) in water samples is described. The following preconcentration steps are used: co-precipitation of cesium on copper ferrocyanide; co-precipitation of plutonium on iron hydroxide; and precipitation of strontium in the carbonate form. The chemical yield is determined by using the tracers: 88Y, 85Sr, 134Cs and 236Pu or 242Pu. The method was applied to the determination of artificial radionuclides in water sources at nuclear test sites - the former Semipalatinsk nuclear test site and the 'Azgir' and 'Lira' test sites. The volume of water samples was 0.5 - 30.0 l, and the mineralization ranged from 0.1g/l to 100 g/l. The determination limits were: < 1 mBq/l for cesium-137; 0.02 mBq/l for plutonium-(239+240); and 1.5 mBq/l for strontium-90. The chemical yield was 60 - 90%

  14. (236)U and (239,)(240)Pu ratios from soils around an Australian nuclear weapons test site.

    Science.gov (United States)

    Tims, S G; Froehlich, M B; Fifield, L K; Wallner, A; De Cesare, M

    2016-01-01

    The isotopes (236)U, (239)Pu and (240)Pu are present in surface soils as a result of global fallout from nuclear weapons tests carried out in the 1950's and 1960's. These isotopes potentially constitute artificial tracers of recent soil erosion and sediment movement. Only Accelerator Mass Spectrometry has the requisite sensitivity to measure all three isotopes at these environmental levels. Coupled with its relatively high throughput capabilities, this makes it feasible to conduct studies of erosion across the geographical extent of the Australian continent. In the Australian context, however, global fallout is not the only source of these isotopes. As part of its weapons development program the United Kingdom carried out a series of atmospheric and surface nuclear weapons tests at Maralinga, South Australia in 1956 and 1957. The tests have made a significant contribution to the Pu isotopic abundances present in the region around Maralinga and out to distances ∼1000 km, and impact on the assessment techniques used in the soil and sediment tracer studies. Quantification of the relative fallout contribution derived from detonations at Maralinga is complicated owing to significant contamination around the test site from numerous nuclear weapons safety trials that were also carried out around the site. We show that (236)U can provide new information on the component of the fallout that is derived from the local nuclear weapons tests, and highlight the potential of (236)U as a new fallout tracer. PMID:26141189

  15. Fission fragment angular distributions in proton-induced fission of 209 Bi(p,t and 197 Au(p,f

    Directory of Open Access Journals (Sweden)

    S. S.

    2001-12-01

    Full Text Available   The fission fragment angular distributions have been measured for proton-induced fission of 209Bi and 197Au nuclei using surface barrier detectors at several energies between 25 MeV and 30 MeV. The experimental anisotropies are found to be in agreement with the predictions of the Standard Saddle-Point Statistical Model (SSPSM. The fission cross sections of 209Bi 197Au nuclei were also measured and compared with the previous works.

  16. Life time of the HFS transition in Li-like {sup 209}Bi{sup 80+}

    Energy Technology Data Exchange (ETDEWEB)

    Geppert, C.; Noertershaeuser, W. [Institut fuer Kernchemie, Uni Mainz (Germany); GSI, Darmstadt (Germany); Hannen, V.; Joehren, R.; Ortjohann, H.W.; Vollbrecht, J.; Weinheimer, C. [Institut fuer Kernphysik, Uni Muenster (Germany); Kuehl, T. [Institut fuer Kernchemie, Uni Mainz (Germany); GSI, Darmstadt (Germany); Helmholtz Institut Jena (Germany); S' anchez, R.; Winters, D. [GSI, Darmstadt (Germany); Stoehlker, T. [Institut fuer Kernchemie, Uni Mainz (Germany); GSI, Darmstadt (Germany); Helmholtz Institut Jena (Germany); Uni Jena (Germany)

    2014-07-01

    Measuring the hyperfine splitting of heavy, highly charged ions enables tests of QED in strong fields. HFS calculations have a relative uncertainty of more than 10{sup -3} due to the distribution of the magnetic moment (Bohr-Weisskopf-Effekt). With an appropriate comparison of H- and Li-like ions this nuclear structure contribution can be suppressed. Bismuth is a suitable element for these studies, as the HFS splitting for both configurations are in a wavelength range suitable for laser spectroscopy. For this purpose the two ion species were stored in the Experimental Storage Ring at GSI at a velocity of β = 0.71. To efficiently collect the forward emitted photons a specially developed movable detector system was used. Thereby the HFS of Li-like {sup 209}Bi{sup 80+} was successfully measured for the first time. Besides the determination of the transition energy it was possible to extract the lifetime of the transition out of the collected data. The corresponding analysis and the results are presented on this poster.

  17. Estimates of /sup 239-240/Pu + 241Am inventory, spatial pattern, and soil tonnage for removal at nuclear site-201, NTS

    International Nuclear Information System (INIS)

    Estimates of /sup 239-240/Pu + 241Am inventory and spatial pattern in surface soil are given for Nuclear Site (NS)-201 in Area 18 on the Nevada Test Site (NTS). These estimates were obtained using Kriging techniques and the estimated average /sup 239-240/Pu to 241Am ratio of 7.5. (Henceforth, Pu and Am refer to /sup 239-240/Pu and 241Am.) Estimated concentration contours, 68% confidence bands on contours, and estimated average concentrations in 100- x 100-foot blocks are given. The total Pu + Am inventory estimated to be in the top 5 cm of soil over the defined area is approximately 9.4 curies. Lower and upper limits on this inventory estimate are 4 and 30 curies. It is estimated that about 33 acres (approx. = 13 hectares) of land are contaminated at levels greater than 160 pCi/g and about 51 acres (approx. = 21 hectares) to levels greater than 40 pCi/g. Approximately 23,000 tons of soil would need to be removed (to 15-cm depth) to clean up all areas with estimated concentrations greater than or equal to 160 pCi/g. About 36,000 tons would require removal at the 40- pCi/g level. The above estimates will be updated when additional data become available early in Calender Year 1980. 10 references, 7 figures, 1 table

  18. Spatial distributions of {sup 137}Cs and {sup 239+240}Pu in surface seawater within the Exclusive Economic Zone of East Coast Peninsular Malaysia

    Energy Technology Data Exchange (ETDEWEB)

    Ahmad, Zaharudin, E-mail: zahar@nuclearmalaysia.gov.m [Radiochemistry and Environmental Group, Malaysian Nuclear Agency (Nuclear Malaysia), Bangi, 43000 Kajang (Malaysia); Mei-Wo, Yii; Abu Bakar, Ahmad Sanadi; Shahar, Hidayah [Radiochemistry and Environmental Group, Malaysian Nuclear Agency (Nuclear Malaysia), Bangi, 43000 Kajang (Malaysia)

    2010-09-15

    The studies of {sup 137}Cs and {sup 239+240}Pu distributions in surface seawater at South China Sea within the Exclusive Economic Zone (EEZ) of Peninsular Malaysia were carried out in June 2008. The analysis results will serve as additional information to the expanded baseline data for Malaysia's marine environment. Thirty locations from extended study area were identified in the EEZ from which large volumes of surface seawater samples were collected. Different co-precipitation techniques were employed to concentrate cesium and plutonium separately. A known amount of {sup 134}Cs and {sup 242}Pu tracers were used as yield determinant. The precipitate slurry was collected and oven dried at 60 {sup o}C for 1-2 days. Cesium precipitate was fine-ground and counted using gamma-ray spectrometry system at 661.62 keV, while plutonium was separated from other radionuclides using anion exchange, electrodeposited and counted using alpha spectrometry. The activity concentrations of {sup 137}Cs and {sup 239+240}Pu were in the range of 3.40-5.89 Bq/m{sup 3} and 2.3-7.9 mBq/m{sup 3}, respectively. The {sup 239+240}Pu/{sup 137}Cs ratios indicate that there are no new inputs of these radionuclides into the area.

  19. Spatial distributions of (137)Cs and (239+240)Pu in surface seawater within the Exclusive Economic Zone of East Coast Peninsular Malaysia.

    Science.gov (United States)

    Ahmad, Zaharudin; Mei-Wo, Yii; Abu Bakar, Ahmad Sanadi; Shahar, Hidayah

    2010-09-01

    The studies of (137)Cs and (239+240)Pu distributions in surface seawater at South China Sea within the Exclusive Economic Zone (EEZ) of Peninsular Malaysia were carried out in June 2008. The analysis results will serve as additional information to the expanded baseline data for Malaysia's marine environment. Thirty locations from extended study area were identified in the EEZ from which large volumes of surface seawater samples were collected. Different co-precipitation techniques were employed to concentrate cesium and plutonium separately. A known amount of (134)Cs and (242)Pu tracers were used as yield determinant. The precipitate slurry was collected and oven dried at 60(o)C for 1-2 days. Cesium precipitate was fine-ground and counted using gamma-ray spectrometry system at 661.62keV, while plutonium was separated from other radionuclides using anion exchange, electrodeposited and counted using alpha spectrometry. The activity concentrations of (137)Cs and (239+240)Pu were in the range of 3.40-5.89Bq/m(3) and 2.3-7.9mBq/m(3), respectively. The (239+240)Pu/(137)Cs ratios indicate that there are no new inputs of these radionuclides into the area. PMID:20430636

  20. Examining (239+240)Pu, (210)Pb and historical events to determine carbon, nitrogen and phosphorus burial in mangrove sediments of Moreton Bay, Australia.

    Science.gov (United States)

    Sanders, Christian J; Santos, Isaac R; Maher, Damien T; Breithaupt, Joshua L; Smoak, Joseph M; Ketterer, Michael; Call, Mitchell; Sanders, Luciana; Eyre, Bradley D

    2016-01-01

    Two sediment cores were collected in a mangrove forest to construct geochronologies for the previous century using natural and anthropogenic radionuclide tracers. Both sediment cores were dated using (239+240)Pu global fallout signatures as well as (210)Pb, applying both the Constant Initial Concentration (CIC) and the Constant Rate of Supply (CRS) models. The (239+240)Pu and CIC model are interpreted as having comparable sediment accretion rates (SAR) below an apparent mixed region in the upper ∼5 to 10 cm. In contrast, the CRS dating method shows high sediment accretion rates in the uppermost intervals, which is substantially reduced over the lower intervals of the 100-year record. A local anthropogenic nutrient signal is reflected in the high total phosphorus (TP) concentration in younger sediments. The carbon/nitrogen molar ratios and δ(15)N values further support a local anthropogenic nutrient enrichment signal. The origin of these signals is likely the treated sewage discharge to Moreton Bay which began in the early 1970s. While the (239+240)Pu and CIC models can only produce rates averaged over the intervals of interest within the profile, the (210)Pb CRS model identifies elevated rates of sediment accretion, organic carbon (OC), nitrogen (N), and TP burial from 2000 to 2013. From 1920 to 2000, the three dating methods provide similar OC, N and TP burial rates, ∼150, 10 and 2 g m(-2) year(-1), respectively, which are comparable to global averages. PMID:26004816

  1. A study on artificial radionuclides ({sup 134}Cs, {sup 137}Cs and {sup 239+240}Pu) distribution in the sediment form lake euiam

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Seung Hwan; Lee, Sang Han; Oh, Jung Suk; Choi, Jong Ki [Korea Research Institute of Standards and Science, Daejeon (Korea, Republic of); Kang, Tae Gu [National Institute of Environmental Research, Sejong (Korea, Republic of)

    2015-12-15

    The objective of this study is to identify the radionuclide distribution in public water by carrying out the analysis of artificial radionuclides(({sup 134}Cs, {sup 137}Cs, {sup 239+240}Pu), natural radionuclide({sup 210}Pb) and TOC in the lake Euiam sediment in Chuncheon, South Korea. The {sup 134}Cs concentration in all lake sediments showed below MDA values, and the {sup 137}Cs concentration in lake sediment were ranged from MDA to 8.79 Bq · kg{sup -1}-dry. The {sup 137}Cs concentrations in surface sediment were reported to be 2.4 to 4.2 Bq · kg{sup -1}-dry. The lowest concentration of {sup 137}Cs was reported at St. 4 and the highest concentration was reported at St. 3, respectively. The {sup 239+240}Pu concentration in lake sediment were ranged from 0.049 to 0.47 Bq · kg{sup -1}-dry. The lowest concentration of was reported at St. 2 and the highest concentration was reported at St. 3. The correlation(r) between the {sup 239+240}Pu concentration and {sup 137}Cs concentration in lake sediment presented higher values (0.54 to 0.97) and this suggests the behavior and origin of {sup 137}Cs is identical to the {sup 239+240}Pu in the sediment. The {sup 134}Cs concentration below MDA value and the {sup 239+240}Pu/{sup 134}Cs ratio(mean value of 0.041) indicated that the artificial radionuclides in the sediment were originated from global fallout by the atmospheric testing of nuclear weapons conducted by former USSR and U.S.A, but not from the Fukushima Daiichi NPP accident. The sedimentation rate derived from {sup 2}'1{sup 0}Pb age-dating method at St. 2 is calculated to be 0.31±0.06 cm · y{sup -1}. This value is similar to the value (0.41±0.05 cm · y{sup -1}) estimated from the {sup 137}Cs maximum peak produced from early 1960's. The content of TOC in lake Euiam sediments varied from 0.20 to 13.01%. While the highest correlation between TOC and {sup 137}Cs concentration in the sediment were found at St. 1, the others presented the low correlation.

  2. Experimental Cross Sections for Reactions of Heavy Ions and 208Pb, 209Bi, 238U, and 248Cm Targets

    Energy Technology Data Exchange (ETDEWEB)

    Patin, Joshua B.

    2002-05-24

    The study of the reactions between heavy ions and {sup 208}Pb, {sup 209}Bi, {sup 238}U, and {sup 248} Cm targets was performed to look at the differences between the cross sections of hot and cold fusion reactions. Experimental cross sections were compared with predictions from statistical computer codes to evaluate the effectiveness of the computer code in predicting production cross sections. Hot fusion reactions were studied with the MG system, catcher foil techniques and the Berkeley Gas-filled Separator (BGS). 3n- and 4n-exit channel production cross sections were obtained for the {sup 238}U({sup 18}O,xn){sup 256-x}Fm, {sup 238}U({sup 22}Ne,xn){sup 260-x}No, and {sup 248}Cm({sup 15}N,xn){sup 263-x}Lr reactions and are similar to previous experimental results. The experimental cross sections were accurately modeled by the predictions of the HIVAP code using the Reisdorf and Schaedel parameters and are consistent with the existing systematics of 4n exit channel reaction products. Cold fusion reactions were examined using the BGS. The {sup 208}Pb({sup 48}Ca,xn){sup 256-x}No, {sup 208}Pb({sup 50}Ti,xn){sup 258-x}Rf, {sup 208}Pb({sup 51}V,xn){sup 259-x}Db, {sup 209}Bi({sup 50}Ti,xn){sup 259-x}Db, and {sup 209}Bi({sup 51}V,xn){sup 260-x}Sg reactions were studied. The experimental production cross sections are in agreement with the results observed in previous experiments. It was necessary to slightly alter the Reisdorf and Schaedel parameters for use in the HIVAP code in order to more accurately model the experimental data. The cold fusion experimental results are in agreement with current 1n- and 2n-exit channel systematics.

  3. Determination of the {sup 209}Bi(n,{gamma}){sup 210}Bi and {sup 209}Bi(n,{gamma}){sup 210m,g}Bi reaction cross sections in a cold neutron beam

    Energy Technology Data Exchange (ETDEWEB)

    Borella, A. [European Commission, Joint Research Centre, Institute for Reference Materials and Measurements, B-2440 Geel (Belgium); SCK-CEN, Boeretang 200, B-2400 Mol (Belgium); Belgya, T. [Institute of Isotope, Hungarian Academy of Sciences, POB 77, H-1525 Budapest (Hungary); Kopecky, S. [European Commission, Joint Research Centre, Institute for Reference Materials and Measurements, B-2440 Geel (Belgium); Gunsing, F. [CEA/Saclay, DSM/Irfu, F-91191 Gif-sur-Yvette (France); Moxon, M. [Hyde Copse 3, Marcham (United Kingdom); Rejmund, M. [GANIL, F-14076 Caen (France); Schillebeeckx, P., E-mail: peter.schillebeeckx@ec.europa.e [European Commission, Joint Research Centre, Institute for Reference Materials and Measurements, B-2440 Geel (Belgium); Szentmiklosi, L. [Institute of Isotope, Hungarian Academy of Sciences, POB 77, H-1525 Budapest (Hungary)

    2011-01-15

    Gamma-ray transitions following neutron capture in {sup 209}Bi have been studied at the cold neutron beam facility of the Budapest Neutron Centre. Measurements have been performed using a coaxial HPGe detector with Compton suppression. Partial capture cross sections at a velocity of 2200 m/s (or a neutron energy of 25.3 meV) have been deduced relatively to the one for the 4055 keV transition after thermal neutron capture in {sup 209}Bi. This partial cross section of (8.07 {+-} 0.14) mb has in turn been obtained from measurements with a bismuth nitrate target relatively to the cross section for the 1884 keV transition after thermal neutron capture in {sup 14}N. Shell model calculations have been performed to deduce the half-life of the 3rd excited state at 320 keV and to assign the M1 multipolarity of the 320 keV transition to the ground state. Lower limits of (21.4 {+-} 0.8) mb and (18.2 {+-} 0.7) mb for the cross sections to the ground state and to the isomeric state, respectively, have been deduced from the data for the gamma rays feeding these states. The results obtained in this work are in good agreement with experimental data reported in the literature. The thermal total capture cross section has been compared with the contribution due to observed s-wave resonances.

  4. Evaluation of fission cross sections and covariances for {sup 233}U, {sup 235}U, {sup 238}U, {sup 239}Pu, {sup 240}Pu, and {sup 241}Pu

    Energy Technology Data Exchange (ETDEWEB)

    Kawano, Toshihiko [Kyushu Univ., Fukuoka (Japan); Matsunobu, Hiroyuki [Data Engineering, Inc. (Japan); Murata, Toru [AITEL Corporation, Tokyo (JP)] [and others

    2000-02-01

    A simultaneous evaluation code SOK (Simultaneous evaluation on KALMAN) has been developed, which is a least-squares fitting program to absolute and relative measurements. The SOK code was employed to evaluate the fission cross sections of {sup 233}U, {sup 235}U, {sup 238}U, {sup 239}Pu, {sup 240}Pu, and {sup 241}Pu for the evaluated nuclear data library JENDL-3.3. Procedures of the simultaneous evaluation and the experimental database of the fission cross sections are described. The fission cross sections obtained were compared with evaluated values given in JENDL-3.2 and ENDF/B-VI. (author)

  5. {sup 238}Pu, {sup 239+240}Pu and {sup 241}Am levels in the terrestrial and aquatic environment of the Loire and Garonne rivers basins (France)

    Energy Technology Data Exchange (ETDEWEB)

    Rousseau, G.; Mokili, M.B.; Le Roy, C.; Pagano, V. [SUBATECH/IN2P3 (France); Gontier, G.; Boyer, C. [EDF-DPI-DIN-CIDEN (France); Chardon, P. [CNRS/IN2P3 (France); Hemidy, P.Y. [EDF-DPN-UNIE-GPRE-IEV (France)

    2014-07-01

    Plutonium and americium long-lived alpha emitter isotopes can be found in the environment because of atmospheric global fallout due to thermonuclear tests performed between 1945 and 1980, to the American SNAP 9A satellite explosion in 1964, to the Chernobyl nuclear power plant accident,... In France, the nuclear safety authority does not allow the release of artificial alpha emitters from nuclear power plants. Thus, monitoring is performed to verify the absence of these alpha emitters in liquid discharges to respect the limits set by the regulations. These thresholds ensure a very low dosimetric impact to the population compared to other radionuclides. With the objective of environmental monitoring around nuclear facilities, activity measurements of long-lived alpha emitters are carried out to detect the traces of these radionuclides. Analysis of low activity by alpha spectrometry after chemical steps were performed and used to determine the {sup 238}Pu, {sup 239+240}Pu and {sup 241}Am activities on a large set of environmental solid samples likely to be encountered in environmental monitoring as soils, sediments, terrestrial and aquatic bio-indicators. The samples collected in the terrestrial and aquatic environment of the Loire and Garonne rivers basins (France) was investigated for the 2009-2014 period. It was found that the mean activity concentration of the most frequently detected was for the radionuclide {sup 238}Pu: from <0.00031 to 0.0061 Bq/kg dry in terrestrial samples and from <0.00086 to 0.011 Bq/kg dry in aquatic samples; for the radionuclide {sup 239+240}Pu: from 0.00041 to 0.150 Bq/kg dry in terrestrial samples and from 0.0023 to 0.240 Bq/kg dry in aquatic samples and for the radionuclide {sup 241}Am: from <0.00086 to 0.087 Bq/kg dry in terrestrial samples and from 0.0022 to 0.120 Bq/kg dry in aquatic samples. {sup 238}Pu/{sup 239+240}Pu and {sup 241}Am/{sup 239+240}Pu ratios determined are in accordance with an environmental contamination due to

  6. Model testing of radioactive contamination by {sup 90}Sr, {sup 137}Cs and {sup 239,240}Pu of water and bottom sediments in the Techa River (Southern Urals, Russia)

    Energy Technology Data Exchange (ETDEWEB)

    Kryshev, I.I. [Scientific and Production Association ' Typhoon' , 82 Lenin Ave., Obninsk, Kaluga Region, 249038 (Russian Federation)], E-mail: ecomod@obninsk.com; Boyer, P.; Monte, L.; Brittain, J.E.; Dzyuba, N.N.; Krylov, A.L.; Kryshev, A.I.; Nosov, A.V.; Sanina, K.D.; Zheleznyak, M.I. [Scientific and Production Association ' Typhoon' , 82 Lenin Ave., Obninsk, Kaluga Region, 249038 (Russian Federation)

    2009-03-15

    This paper presents results of testing models for the radioactive contamination of river water and bottom sediments by {sup 90}Sr, {sup 137}Cs and {sup 239,240}Pu. The scenario for the model testing was based on data from the Techa River (Southern Urals, Russia), which was contaminated as a result of discharges of liquid radioactive waste into the river. The endpoints of the scenario were model predictions of the activity concentrations of {sup 90}Sr, {sup 137}Cs and {sup 239,240}Pu in water and bottom sediments along the Techa River in 1996. Calculations for the Techa scenario were performed by six participant teams from France (model CASTEAUR), Italy (model MARTE), Russia (models TRANSFER-2, CASSANDRA, GIDRO-W) and Ukraine (model RIVTOX), all using different models. As a whole, the radionuclide predictions for {sup 90}Sr in water for all considered models, {sup 137}Cs for MARTE and TRANSFER-2, and {sup 239,240}Pu for TRANSFER-2 and CASSANDRA can be considered sufficiently reliable, whereas the prediction for sediments should be considered cautiously. At the same time the CASTEAUR and RIVTOX models estimate the activity concentrations of {sup 137}Cs and {sup 239,240}Pu in water more reliably than in bottom sediments. The models MARTE ({sup 239,240}Pu) and CASSANDRA ({sup 137}Cs) evaluated the activity concentrations of radionuclides in sediments with about the same agreement with observations as for water. For {sup 90}Sr and {sup 137}Cs the agreement between empirical data and model predictions was good, but not for all the observations of {sup 239,240}Pu in the river water-bottom sediment system. The modelling of {sup 239,240}Pu distribution proved difficult because, in contrast to {sup 137}Cs and {sup 90}Sr, most of models have not been previously tested or validated for plutonium.

  7. Measurement of the neutron-induced fission cross-section of {sup 243}Am relative to {sup 235}U from 0.5 to 20 MeV

    Energy Technology Data Exchange (ETDEWEB)

    Belloni, F.; Milazzo, P.M.; Abbondanno, U.; Fujii, K.; Moreau, C. [Istituto Nazionale di Fisica Nucleare, Trieste (Italy); Calviani, M. [Laboratori Nazionali di Legnaro, Istituto Nazionale di Fisica Nucleare, Legnaro (Italy); CERN, Geneva (Switzerland); Colonna, N.; Barbagallo, M.; Marrone, S.; Meaze, M.H.; Tagliente, G.; Terlizzi, R. [Istituto Nazionale di Fisica Nucleare, Bari (Italy); Mastinu, P.; Gramegna, F. [Lab. Nazionali di Legnaro, Istituto Nazionale di Fisica Nucleare, Legnaro (Italy); Aerts, G.; Andriamonje, S.; Berthoumieux, E.; Dridi, W.; Gunsing, F.; Pancin, J.; Perrot, L.; Plukis, A. [Irfu, CEA, Gif-sur-Yvette (France); Alvarez, H.; Cano-Ott, D.; Duran, I.; Embid-Segura, M.; Gonzalez-Romero, E.; Paradela, C.; Tarrio, D. [Univ. de Santiago de Compostela, Galicia (Spain); Alvarez-Velarde, F.; Guerrero, C.; Martinez, T.; Villamarin, D.; Vincente, M.C. [Centro de Investigaciones Energeticas Medioambientales y Technologicas, Madrid (Spain); Andrzejewski, J.; Marganiec, J. [Univ. of Lodz (Poland); Audouin, L.; Dillmann, I.; Heil, M.; Kaeppeler, F.; Mosconi, M.; Plag, R.; Voss, F.; Walter, S.; Wisshak, K. [Karlsruhe Inst. of Technology, Eggenstein-Leopoldshafen (Germany). Inst. fuer Kernphysik; Badurek, G.; Jericha, E.; Leeb, H.; Oberhummer, H. [Technische Univ. Wien, Atominstitut der Oesterreichischen Universitaeten, Wien (Austria); Baumann, P.; David, S.; Kerveno, M.; Lukic, S.; Rudolf, G. [IReS, Centre National de la Recherche Scientifique/IN2P3, Strasbourg (France); Becvar, F.; Krticka, M. [Charles Univ., Faculty of Mathematics and Physics, Prague (Czech Republic); Calvino, F.; Cortes, G.; Poch, A.; Pretel, C. [Univ. Politecnica de Catalunya, Barcelona (Spain); Capote, R. [NAPC/Nuclear Data Section, International Atomic Energy Agency, Vienna (Austria); Univ. de Sevilla (Spain); Carrapico, C.; Goncalves, I.; Salgado, J.; Santos, C.; Tavora, L.; Vaz, P. [Inst. Tecnologico e Nuclear, Lisbon (Portugal)] [and others

    2011-12-15

    The ratio of the neutron-induced fission cross-sections of {sup 243}Am and {sup 235}U was measured in the energy range from 0.5 to 20 MeV with uncertainties of {approx} 4%. The experiment was performed at the CERN n{sub T}OF facility using a fast ionization chamber. With the good counting statistics that could be achieved thanks to the high instantaneous flux and the low backgrounds, the present results are useful for resolving discrepancies in previous data sets and are important for future reactors with improved fuel burn-up. (orig.)

  8. Neutron-induced fission cross sections of 233U and 243Am in the energy range 0.5 Mev En 20 MeV @ n_TOF

    CERN Document Server

    Belloni, F; Milazzo, P M; Calviani, M; Colonna, N; Mastinu, P; Abbondanno, U; Aerts, G; Álvarez, H; Álvarez-Velarde, F; Andriamonje, S; Andrzejewski, J; Assimakopoulos, P; Audouin, L; Badurek, G; Baumann, P; Becvár, F; Berthoumieux, E; Calviño, F; Cano-Ott, D; Capote, R; Carrapiço, C; Cennini, P; Chepel, V; Chiaveri, E; Cortes, G; Couture, A; Cox, J; Dahlfors, M; David, S; Dillmann, I; Domingo-Pardo, C; Dridi, W; Duran, I; Eleftheriadis, C; Embid-Segura, M; Ferrant, L; Ferrari, A; Ferreira-Marques, R; Fujii, K; Furman, W; Goncalves, I; González-Romero, E; Gramegna, F; Guerrero, C; Gunsing, F; Haas, B; Haight, R; Heil, M; Herrera-Martinez, A; Igashira, M; Jericha, E; Käppeler, F; Kadi, Y; Karadimos, D; Karamanis, D; Kerveno, M; Koehler, P; Kossionides, E; Krticka, M; Lampoudis, C; Leeb, H; Lindote, A; Lopes, I; Lozano, M; Lukic, S; Marganiec, J; Marrone, S; Martínez, T; Massimi, C; Mengoni, A; Moreau, C; Mosconi, M; Neves, F; Oberhummer, H; O'Brien, S; Pancin, J; Papachristodoulou, C; Papadopoulos, C; Paradela, C; Patronis, N; Pavlik, A; Pavlopoulos, P; Perrot, L; Pigni, M T; Plag, R; Plompen, A; Plukis, A; Poch, A; Praena, J; Pretel, C; Quesada, J; Rauscher, T; Reifarth, R; Rubbia, C; Rudolf, G; Rullhusen, P; Salgado, J; Santos, C; Sarchiapone, L; Savvidis, I; Stephan, C; Tagliente, G; Tain, J L; Tassan-Got, L; Tavora, L; Terlizzi, R; Vannini, G; Vazl, P; Ventura, A; Villamarin, D; Vincente, M C; Vlachoudis, V; Vlastou, R; Voss, F; Walter, S; Wiescher, M; Wisshak, K

    2011-01-01

    Neutron-induced fission cross-sections of actinides have been recently measured at the neutron time of flight facility n_TOF at CERN in the frame of a research project involving isotopes relevant for nuclear astrophysics and nuclear technologies. Fission fragments are detected by a gas counter with good discrimination between nuclear fission products and background events. Neutron-induced fission cross-sections of 233U and 243Am were determined relative to 235U. The present paper reports the results obtained at neutron energies between 0.5 and 20 MeV.

  9. The neutron capture cross sections of {sup 237}Np(n,{gamma}) and {sup 240}Pu(n,{gamma}) and its relevance in the transmutation of nuclear waste

    Energy Technology Data Exchange (ETDEWEB)

    Guerrero, C.; Abbondanno, U.; Aerts, G.; Alvarez, H.; Alvarez-Velarde, F.; Andriamonje, S.; Andrzejewski, J.; Assimakopoulos, P.; Audouin, L.; Badurek, G.; Baumann, P.; Becvar, F.; Berthoumieux, E.; Calvino, F.; Calviani, M.; Cano-Ott, D.; Capote, R.; Carrapico, C.; Cennini, P.; Chepel, V.; Chiaveri, E.; Colonna, N.; Cortes, G.; Couture, A.; Cox, J.; Dahlfors, M.; David, S.; Dillmann, I.; Domingo-Pardo, C.; Dridi, W.; Duran, I.; Eleftheriadis, C.; Embid-Segura, M.; Ferrant, L.; Ferrari, A.; Ferreira-Marques, R.; Fujii, K.; Furman, W.; Goncalves, I.; Gonzalez-Romero, E.; Gramegna, F.; Gunsing, F.; Haas, B.; Haight, R.; Heil, M.; Herrera-Martinez, A.; Igashira, M.; Jericha, E.; Kappeler, F.; Kadi, Y.; Karadimos, D.; Karamanis, D.; Kerveno, M.; Koehler, P.; Kossionides, E.; Krticka, M.; Lampoudis, C.; Leeb, H.; Lindote, A.; Lopes, I.; Lozano, M.; Lukic, S.; Marganiec, J.; Marrone, S.; Martinez, T.; Massimi, C.; Mastinu, P.; Mengoni, A.; Milazzo, P.M.; Moreau, C.; Mosconi, M.; Neves, F.; Oberhummer, H.; O' Brien, S.; Pancin, J.; Papachristodoulou, C.; Papadopoulos, C.; Paradela, C.; Patronis, N.; Pavlik, A.; Pavlopoulos, P.; Perrot, L.; Pigni, M.T.; Plag, R.; Plompen, A.; Plukis, A.; Poch, A.; Praena, J.; Pretel, C.; Quesada, J.; Rauscher, T.; Reifarth, R.; Rubbia, C.; Rudolf, G.; Rullhusen, P.; Salgado, J.; Santos, C.; Sarchiapone, L.; Savvidis, I.; Stephan, C.; Tagliente, G.; Tain, J.L.; Tassan-Got, L.; Tavora, L.; Terlizzi, R.; Vannini, G.; Vaz, P.; Ventura, A.; Villamarin, D.; Vincente, M.C.; Vlachoudis, V.; Vlastou, R.; Voss, F.; Walter, S.; Wiescher, M.; Wisshak, K

    2008-07-01

    Neutron capture cross sections of actinides are of great relevance for the Transmutation of Nuclear Waste in Accelerator Driven Systems (ADS) and Generation-IV reactors. The neutron capture cross sections of {sup 237}Np and {sup 240}Pu in the range of 1 eV to 2 keV were measured at the n-TOF facility with a Total Absorption Calorimeter. The data have been analyzed with the SAMMY code. The corresponding covariance matrices have been generated. The final cross sections are presented and compared to the previously existing ones.The n-TOF {sup 237}Np {sigma}(n,{gamma}) is in agreement with the evaluated data files below 300 eV and its is lower by 10 to 15% up to 2 keV. This discrepancy with the evaluated data files is also observed in the capture cross section derived from the transmission measurements of Gressier et al. In the case of the {sup 240}Pu {sigma}(n,{gamma}), the n-TOF {sigma}(n,{gamma}) agrees within uncertainties with JENDL-3.3 and JEFF-3.1, except for a group of resonances around 800 eV. Endf/B-VII data are lower than n-TOF and the mentioned evaluations, with differences that increase with neutron energy up to 15-20 per cent.

  10. Measurement of the 240Pu/239Pu mass ratio using a transition-edge-sensor microcalorimeter for total decay energy spectroscopy.

    Science.gov (United States)

    Hoover, Andrew S; Bond, Evelyn M; Croce, Mark P; Holesinger, Terry G; Kunde, Gerd J; Rabin, Michael W; Wolfsberg, Laura E; Bennett, Douglas A; Hays-Wehle, James P; Schmidt, Dan R; Swetz, Daniel; Ullom, Joel N

    2015-04-01

    We have developed a new category of sensor for measurement of the (240)Pu/(239)Pu mass ratio from aqueous solution samples with advantages over existing methods. Aqueous solution plutonium samples were evaporated and encapsulated inside of a gold foil absorber, and a superconducting transition-edge-sensor microcalorimeter detector was used to measure the total reaction energy (Q-value) of nuclear decays via heat generated when the energy is thermalized. Since all of the decay energy is contained in the absorber, we measure a single spectral peak for each isotope, resulting in a simple spectral analysis problem with minimal peak overlap. We found that mechanical kneading of the absorber dramatically improves spectral quality by reducing the size of radioactive inclusions within the absorber to scales below 50 nm such that decay products primarily interact with atoms of the host material. Due to the low noise performance of the microcalorimeter detector, energy resolution values of 1 keV fwhm (full width at half-maximum) at 5.5 MeV have been achieved, an order of magnitude improvement over α-spectroscopy with conventional silicon detectors. We measured the (240)Pu/(239)Pu mass ratio of two samples and confirmed the results by comparison to mass spectrometry values. These results have implications for future measurements of trace samples of nuclear material. PMID:25723106

  11. Thermal neutron capture cross-section measurements of 243Am and 242Pu using the new mini-INCA α- and γ-spectroscopy station

    International Nuclear Information System (INIS)

    In the framework of the Mini-INCA project, dedicated to the study of Minor Actinide transmutation process in high neutron fluxes, an α- and γ-spectroscopy station has been developed and installed at the High Flux Reactor of the Laue-Langevin Institut. This set-up allows short irradiations as well as long irradiations in a high quasi-thermal neutron flux and post-irradiation spectroscopy analysis. It is well suited to measure precisely, in reference to 59Co cross-section, neutron capture cross-sections, for all the actinides, in the thermal energy region. The first measurements using this set-up were done on 243Am and 242Pu isotopes. Cross-section values, at En=0.025eV, were found to be (81.8+/-3.6)b for 243Am and (22.5+/-1.1)b for 242Pu. These values differ from evaluated data libraries by a factor of 9% and 17%, respectively, but are compatible with the most recent measurements, validating by the way the experimental apparatus

  12. The use of isotopic correlation technique for determination of sup(241)Am and sup(243)Am concentration in nuclear irradiated fuels

    International Nuclear Information System (INIS)

    In the last years the isotopic correlation technique is emerging as a powerful tool for the determination of concentration and isotopic composition of heavy nuclides in the nuclear fuel cycle. Accordingly, this technique has gained significant importance for the safeguard of the nuclear materials as well as for the accounting and build up of actinides elements in the irradiated nuclear fuels. In this work 42 isotopic correlations between the nuclides sup(241)Am and sup(243)Am and post irradiation isotopic data of 7 samples from fuel element BE-124 and 1 sample from fuel element BE-120 from the Obrigheim pressurized water nuclear power reactor, Federal Republic of Germany, were proposed. These isotopic correlations allowed to estimate the isotopic concentrations of sup(241)Am and sup(243)Am with an average deviation, relative to the experimental data obtained from isotopic dilution mass spectrometry technique, of 10%. These results are more precise than those found using the computer code ORIGEN 2 demonstrating the great potential of this technique for the determination of isotopic concentration and build up of those nuclides in irradiated nuclear fuels. The analytical and other experimental aspects of the post irradiation isotopic analysis of nuclear fuels are also discussed. (author)

  13. Complete and incomplete fusion cross sections for 6Li+209Bi reaction in multi-body classical molecular dynamical model

    International Nuclear Information System (INIS)

    Using the multi-body Classical Molecular Dynamics simulation of 6Li+209Bi reaction it is shown that: (i) the breakup of a projectile fragment near the barrier leads to substantial increase in the ICF probabilities; (ii) the expected increase in σCF on relaxation of the rigid-body (RB) constraint on the projectile is compensated by reduction in the flux leading to CF, due to ICF events; (iii) the breakup probability increases with ECM and, for given ECM it also increases as b increases and peaks around some b>0, while cross sections σCF and σTF were calculated for b=0 only Therefore, we present the results of σCF (Complete Fusion) and σTF (Total Fusion) calculations which are obtained at critical impact parameter, bcr, where many ICF channels open up and compare with the calculations performed at b=0 only, where only few ICF channels open up

  14. Study of viscosity on the fission dynamics of the excited nuclei 228U produced in 19F + 209Bi reactions

    International Nuclear Information System (INIS)

    A two-dimensional (2D) dynamical model based on Langevin equations was applied to study the fission dynamics of the compound nuclei 228U produced in 19F + 209Bi reactions at intermediate excitation energies. The distance between the centers of masses of the future fission fragments was used as the first dimension and the projection of the total spin of the compound nucleus onto the symmetry axis, K, was considered as the second dimension in Langevin dynamical calculations. The magnitude of post-saddle friction strength was inferred by fitting measured data on the average pre-scission neutron multiplicity for 228U. It was shown that the results of calculations are in good agreement with the experimental data by using values of the post-saddle friction equal to 6–8 × 1021s-1. (author)

  15. Role of natural organic matter on iodine and (239)(,240)Pu distribution and mobility in environmental samples from the northwestern Fukushima Prefecture, Japan.

    Science.gov (United States)

    Xu, Chen; Zhang, Saijin; Sugiyama, Yuko; Ohte, Nobuhito; Ho, Yi-Fang; Fujitake, Nobuhide; Kaplan, Daniel I; Yeager, Chris M; Schwehr, Kathleen; Santschi, Peter H

    2016-03-01

    In order to assess how environmental factors are affecting the distribution and migration of radioiodine and plutonium that were emitted from the Fukushima Dai-ichi Nuclear Power Plant (FDNPP) accident, we quantified iodine and (239,240)Pu concentration changes in soil samples with different land uses (urban, paddy, deciduous forest and coniferous forest), as well as iodine speciation in surface water and rainwater. Sampling locations were 53-63 km northwest of the FDNPP within a 75-km radius, in close proximity of each other. A ranking of the land uses by their surface soil (forest > deciduous forest > urban > paddy, and (239,240)Pu concentrations ranked as deciduous forest > coniferous forest > paddy ≥ urban. Both were quite distinct from that of (134)Cs and (137)Cs: urban > coniferous forest > deciduous forest > paddy, indicating differences in their sources, deposition phases, and biogeochemical behavior in these soil systems. Although stable (127)I might not have fully equilibrated with Fukushima-derived (129)I, it likely still works as a proxy for the long-term fate of (129)I. Surficial soil (127)I content was well correlated to soil organic matter (SOM) content, regardless of land use type, suggesting that SOM might be an important factor affecting iodine biogeochemistry. Other soil chemical properties, such as Eh and pH, had strong correlations to soil (127)I content, but only within a given land use (e.g., within urban soils). Organic carbon (OC) concentrations and Eh were positively, and pH was negatively correlated to (127)I concentrations in surface water and rain samples. It is also noticeable that (127)I in the wet deposition was concentrated in both the deciduous and coniferous forest throughfall and stemfall water, respectively, comparing to the bulk rainwater. Further, both forest throughfall and stemflow water consisted exclusively of organo-iodine, suggesting all inorganic iodine in the original bulk deposition (∼ 28.6% of total iodine) have

  16. Simultaneous measurement of 239Pu, 240Pu, 241Pu, and 242Pu by high resolution inductively coupled plasma mass spectrometer (HR ICP-MS) in marine sediments

    International Nuclear Information System (INIS)

    Transuranics elements are of particular interest in radioecological studies because of their radiotoxicity and their potential use to decipher source fingerprints and transport processes. The simultaneous measurement of 239Pu, 240Pu, 241Pu, and 242Pu in environmental samples requires a specific chemical procedure. This work deals with an analytical procedure which yields a very high grade of purification of Pu suitable for ultra low level detection by HR ICP-MS, from marine sediments. After the elimination of major elements (Fe, Al, Mg...) by a first chromatographic separation, a new device of purification by solvent extraction and concentration by a second chromatographic separation is used to obtain a concentrated and high purified solution of plutonium. The chemical procedure have been validated on IAEA certified sediment samples and on sediment samples collected in the roads of Cherbourg which had been previously analysed by other techniques (a spectrometry and thermo-ionisation mass spectrometer). (author)

  17. Spatial distribution of (241)Am, (137)Cs, (238)Pu, (239,240)Pu and (241)Pu over 17 year periods in the Ravenglass saltmarsh, Cumbria, UK.

    Science.gov (United States)

    Oh, J-S; Warwick, P E; Croudace, I W

    2009-01-01

    Ninety five surface scrape samples were collected at the Ravenglass saltmarsh and analysed for radionuclides by alpha spectrometry ((238)Pu and (239,240)Pu), gamma spectrometry ((241)Am and (137)Cs) and liquid scintillation counting ((241)Pu). Both (241)Am and (137)Cs activities are compared with those reported by Horrill [1983. Concentrations and spatial distribution of radioactivity in an ungrazed saltmarsh. In: Coughtrey, P.J. (Ed.), Ecological Aspects of Radionuclide Release. British Ecological Society Special Publication No. 3. Blackwell, Oxford, pp. 119-215.] Significant decreases in activities for both radionuclides were observed which is caused by the declining levels of discharges from the Sellafield nuclear reprocessing plant since the 1980s. It has been concluded that the spatial distribution of these radionuclides are controlled by the tidal currents and the clay contents in the sediments. There is evidence of surface erosion of the saltmarsh and redistribution of radionuclides in the saltmarsh using isotopic ratios of measured Pu.

  18. Studying of distribution of 137Cs, 90Sr, 239+240Pu, 241Am and 244Cm according to the organic acids fractions of the alienation zone soils

    International Nuclear Information System (INIS)

    The paper deals with data of research on the distribution of the radionuclides 137Cs, 90Sr, 239+240Pu, 241Am and 244Cm of ''the Chornobyl rains'' by the fractions of the organic matters of derno-podzolic sandy, derno-meadow and peat soils sampled in the alienation zone of the Chornobyl NPP. Functioning of organic matters was carried according to Tyurin's method. It is stressed that, independently on soil type, 137Cs is connected with the mineral contituent by 80-95%. It is found out that, independently on the soil type, 50-70% 137Sr and 15-45% 241Am are associated with fulvic acid fractions. The 241Am and 244Cm distribution according to organic acids taking into account deviations while carrying out determinations is unambiguous. It is found out that in all the soils tested the main quality of 239+24Pu is connected with humic acids

  19. Fission Cross-section Measurements of (233)U, (245)Cm and (241,243)Am at CERN n_TOF Facility

    CERN Document Server

    Calviani, M; Andriamonje, S; Chiaveri, E; Vlachoudis, V; Colonna, N; Meaze, M H; Marrone, S; Tagliente, G; Terlizzi, R; Belloni, F; Abbondanno, U; Fujii, K; Milazzo, P M; Moreau, C; Aerts, G; Berthoumieux, E; Dridi, W; Gunsing, F; Pancin, J; Perrot, L; Plukis, A; Alvarez, H; Duran, I; Paradela, C; Alvarez-Velarde, F; Cano-Ott, D; Gonzalez-Romero, E; Guerrero, C; Martinez, T; Villamarin, D; Vicente, M C; Andrzejewski, J; Marganiec, J; Assimakopoulos, P; Karadimos, D; Karamanis, D; Papachristodoulou, C; Patronis, N; Audouin, L; David, S; Ferrant, L; Isaev, S; Stephan, C; Tassan-Got, L; Badurek, G; Jericha, E; Leeb, H; Oberhummer, H; Pigni, M T; Baumann, P; Kerveno, M; Lukic, S; Rudolf, G; Becvar, F; Krticka, M; Calvino, F; Capote, R; Carrillo De Albornoz, A; Marques, L; Salgado, J; Tavora, L; Vaz, P; Cennini, P; Dahlfors, M; Ferrari, A; Gramegna, F; Herrera-Martinez, A; Kadi, Y; Mastinu, P; Praena, J; Sarchiapone, L; Wendler, H; Chepel, V; Ferreira-Marques, R; Goncalves, I; Lindote, A; Lopes, I; Neves, F; Cortes, G; Poch, A; Pretel, C; Couture, A; Cox, J; O'brien, S; Wiescher, M; Dillman, I; Heil, M; Kappeler, F; Mosconi, M; Plag, R; Voss, F; Walter, S; Wisshak, K; Dolfini, R; Rubbia, C; Domingo-Pardo, C; Tain, J L; Eleftheriadis, C; Savvidis, I; Frais-Koelbl, H; Griesmayer, E; Furman, W; Konovalov, V; Goverdovski, A; Ketlerov, V; Haas, B; Haight, R; Reifarth, R; Igashira, M; Koehler, P; Kossionides, E; Lampoudis, C; Lozano, M; Quesada, J; Massimi, C; Vannini, G; Mengoni, A; Oshima, M; Papadopoulos, C; Vlastou, R; Pavlik, A; Pavlopoulos, P; Plompen, A; Rullhusen, P; Rauscher, T; Rosetti, M; Ventura, A

    2011-01-01

    Neutron-induced fission cross-sections of minor actinides have been measured using the n_TOF white neutron source at CERN, Geneva, as part of a large experimental program aiming at collecting new data relevant for nuclear astrophysics and for the design of advanced reactor systems. The measurements at n_TOF take advantage of the innovative features of the n_TOF facility, namely the wide energy range, high instantaneous neutron flux and good energy resolution. Final results on the fission cross-section of 233U, 245Cm and 243Am from thermal to 20 MeV are here reported, together with preliminary results for 241Am. The measurement have been performed with a dedicated Fast Ionization Chamber (FIC), a fission fragment detector with a very high efficiency, relative to the very well known cross-section of 235U, measured simultaneously with the same detector.

  20. Interaction at the barrier in the systems 9,10,11Be+209Bi: Well-established facts and open questions

    International Nuclear Information System (INIS)

    The experimental data relative to the interaction for the systems 9,10,11Be+209Bi at the Coulomb barrier are critically discussed and compared also with present theories. The break-up (BU) of the two loosely bound projectiles, 9,11Be, seems to influence the fusion process by ''hindering'' the fusion cross-sections; but, contrary to expectations, the 11Be halo structure has no influence, since no ''enhancement'' is evident from the existing data. Attempt to describe simultaneously all the 9Be+209Bi system data: fusion, elastic scattering and BU, within a coupled-channel (CC) approach is only partly successful. It is important, from a theoretical viewpoint, to include in the CC formalism as well as possible the BU process both to continuum states as well as to unbound resonances. More accurate and well-focused experiments are also necessary to pin down this problem. (orig.)

  1. Calculations of Branching Ratios for Radiative-Capture, One-Proton, and Two-Neutron Channels in the Fusion Reaction $^{209}$Bi+$^{70}$Zn

    CERN Document Server

    Ichikawa, Takatoshi; 10.1143/JPSJ.79.074201

    2010-01-01

    We discuss the possibility of the non-one-neutron emission channels in the cold fusion reaction $^{70}$Zn + $^{209}$Bi to produce the element Z=113. For this purpose, we calculate the evaporation-residue cross sections of one-proton, radiative-capture, and two-neutron emissions relative to the one-neutron emission in the reaction $^{70}$Zn + $^{209}$Bi. To estimate the upper bounds of those quantities, we vary model parameters in the calculations, such as the level-density parameter and the height of the fission barrier. We conclude that the highest possibility is for the 2n reaction channel, and its upper bounds are 2.4$%$ and at most less than 7.9% with unrealistic parameter values, under the actual experimental conditions of [J. Phys. Soc. Jpn. {\\bf 73} (2004) 2593].

  2. Study of the di-nuclear system $^{A}$Rb + $^{209}$Bi (Z$_{1}$ + Z$_{2}$ = 120)

    CERN Multimedia

    The exact location of the next spherical shell closures beyond Z = 82, N = 126 is still an open question. According to model predictions shell closures are expected at Z = 114 or 120 or 126 and N = 184. Also experimental data cannot yet give a definite answer. Known nuclei with Z = 114 are too neutron‐deficient with respect to the N = 184 shell and nuclei with Z = 120 and beyond are still unknown. An option for studying reactions of super-heavy systems at Z = 120 and neutron numbers up to 184 becomes possible with the use of $^{209}$Bi targets and neutron‐rich beams. By studying quasi-fission and fusion‐fission reactions, which have significantly larger production cross‐sections than the evaporation residues, a possible influence of shell closures at Z = 120, N = 184 can be explored. Well suitable for such studies will be neutron‐rich rubidium beams at energies of about 5 MeV/u delivered by the HIE‐ISOLDE facility.

  3. Fission cross section calculations for 209Bi target nucleus based on fission reaction models in high energy regions

    Directory of Open Access Journals (Sweden)

    Kaplan Abdullah

    2015-01-01

    Full Text Available Implementation of projects of new generation nuclear power plants requires the solving of material science and technological issues in developing of reactor materials. Melts of heavy metals (Pb, Bi and Pb-Bi due to their nuclear and thermophysical properties, are the candidate coolants for fast reactors and accelerator-driven systems (ADS. In this study, α, γ, p, n and 3He induced fission cross section calculations for 209Bi target nucleus at high-energy regions for (α,f, (γ,f, (p,f, (n,f and (3He,f reactions have been investigated using different fission reaction models. Mamdouh Table, Sierk, Rotating Liquid Drop and Fission Path models of theoretical fission barriers of TALYS 1.6 code have been used for the fission cross section calculations. The calculated results have been compared with the experimental data taken from the EXFOR database. TALYS 1.6 Sierk model calculations exhibit generally good agreement with the experimental measurements for all reactions used in this study.

  4. Thick target yield measurement of {sup 211}At through the nuclear reaction {sup 209}Bi({alpha}, 2n)

    Energy Technology Data Exchange (ETDEWEB)

    Alfarano, A [Institute for Health and Consumer Protection, IHCP, Joint Research Centre, via E. Fermi 1, 21020 Ispra, Varese (Italy); Abbas, K [Institute for Health and Consumer Protection, IHCP, Joint Research Centre, via E. Fermi 1, 21020 Ispra, Varese (Italy); Holzwarth, U [Institute for Health and Consumer Protection, IHCP, Joint Research Centre, via E. Fermi 1, 21020 Ispra, Varese (Italy); Bonardi, M [Universita degli Studi di Milano and INFN-Milano, LASA, Radiochemistry Laboratory, via F.lli Cervi 201, 20090 Segrate, Milan (Italy); Groppi, F [Universita degli Studi di Milano and INFN-Milano, LASA, Radiochemistry Laboratory, via F.lli Cervi 201, 20090 Segrate, Milan (Italy); Alfassi, Z [Department of Nuclear Engineering, Ben Gurion University, 84105 Beer Sheva (Israel); Menapace, E [ENEA, Applied Physics Division, Bologna (Italy); Gibson, P N [Institute for Health and Consumer Protection, IHCP, Joint Research Centre, via E. Fermi 1, 21020 Ispra, Varese (Italy)

    2006-05-15

    Radionuclide Therapy (RNT) and Radioimmunotherapy (RIT) are potentially of great interest for cancer therapy. In many therapeutic applications alpha emitters should be much more effective than already-approved beta emitters due to the short range and high linear energy transfer of alpha particles. {sup 213}Bi is an important alpha emitter already used in clinical trials but the half-life of this radioisotope is short (46 minutes) and so its use is limited for certain therapies. {sup 211}At is potentially very interesting for medical purposes because of its longer half-life of 7.2 hours, and suitable decay scheme. We have studied the cyclotron-based production of {sup 211}At via the reaction {sup 209}Bi({alpha}, 2n), this production route probably being the most promising in the long term. The energy dependence of thick target yields and the reaction cross sections for the production of {sup 211}At and {sup 210}At were determined and found to be in good agreement with literature. The best energy to produce {sup 211}At is 28-29 MeV. The possible production of the undesired, highly radiotoxic, and long-lived alpha-emitting {sup 210}Po (138.38 days), which is produced from decay of {sup 210}At, is also discussed.

  5. Exploring contributions from incomplete fusion in $^{6,7}$Li+$^{209}$Bi and $^{6,7}$Li+$^{198}$Pt reactions

    CERN Document Server

    Parkar, V V; Kailas, S

    2016-01-01

    We use the breakup absorption model to simultaneously describe the measured cross-sections of the Complete fusion (CF), Incomplete fusion (ICF), and Total fusion (TF) in nuclear reactions induced by weakly bound nuclei $^{6,7}$Li on $^{209}$Bi and $^{198}$Pt targets. The absorption cross-sections are calculated using the Continuum Discretized Coupled Channels (CDCC) method with different choices of short range imaginary potentials to get the ICF, CF and TF cross-sections. It is observed that the cross-sections for deuteron-ICF/deuteron-capture are of similar magnitude as the $\\alpha$-ICF/$\\alpha$-capture, in case of $^{6}$Li projectile, while the cross-sections for triton-ICF/triton-capture is more dominant than $\\alpha$-ICF/$\\alpha$-capture in case of $^{7}$Li projectile. Both these observations are also corroborated by the experimental data. The ratio of ICF to TF cross-sections, which defines the value of fusion suppression factor is found to be in agreement with the data available from the literature. The...

  6. Exploring contributions from incomplete fusion in Li,76+209Bi and Li,76+198Pt reactions

    Science.gov (United States)

    Parkar, V. V.; Jha, V.; Kailas, S.

    2016-08-01

    We use the breakup absorption model to simultaneously describe the measured cross sections of complete fusion (CF), incomplete fusion (ICF), and total fusion (TF) in nuclear reactions induced by weakly bound nuclei Li,76 on 209Bi and 198Pt targets. The absorption cross sections are calculated using the continuum discretized coupled channels (CDCC) method with different choices of short-range imaginary potentials to get the ICF, CF, and TF cross sections. It is observed that the cross sections for deuteron ICF / deuteron capture and α ICF / α capture are of similar magnitude, in the case of the 6Li projectile, while the cross sections for the triton ICF / triton capture is more dominant than that of α ICF / α capture in the case of the 7Li projectile. Both these observations are also corroborated by the experimental data. The ratio of ICF to TF cross sections, which defines the value of fusion suppression factor, is found to be in agreement with the data available from the literature. The cross-section ratios of CF/TF and ICF/TF show opposite behavior at below-barrier energies the former decreases while the latter increases as the energy is lowered, which shows the dominance of ICF at below-barrier energies. We have also studied the correlation of the ICF cross sections with the noncapture breakup (NCBU) cross sections as a function of energy, which shows that the NCBU is more significant than ICF at below-barrier energies.

  7. Radionuclides 137Cs, 90Sr, 241Am and 239+240Pu in vegetation cover of the former Semipalatinsk test site

    International Nuclear Information System (INIS)

    The Semipalatinsk Test Site (STS) is one of the largest testing grounds for nuclear weapons. Diverse nuclear explosions were carried out on its territory: 340 underground tests (sites 'Degelen', 'Balapan' and 'Sary-Uzen'), 30 surface and 86 nuclear air explosions (site for radioactive warfare agent (RWA) and 'Experimental Field'). Since the STS was shutdown a large amount of information about current radiological situation in its territory has been collected. In recent years, one of the main problems is gradual transfer of its lands for national economy. Under these conditions, an essential element for prediction of radioactive contamination levels of food products is radionuclides redistribution parameters in soil-plant system used in calculation of doses to the population living within STS territory. Until recently, matter of radionuclides migration from soil to plants has been poorly studied. Individual researches, more or less devoted to this issue occurred in the past, but have virtually no information about accumulation of transuranic radionuclides in plants. More regular studies in this direction have been initiated recently. Between 2007 and 2013 features of artificial radionuclides accumulation in certain plant species under radioactive tunnel watercourses at 'Degelen' site were studied. We've obtained statistically reliable data characterizing accumulation of radionuclides, including 239+240Pu and 241Am, in steppe plants at 'Experimental field' site. The content of radionuclides in plants was researched at the RWA site. Comprehensive ecological survey in order to release the lands to the national economic turnover investigated parameters of radionuclides accumulation in steppe grasses at conditionally 'background' areas of STS and some parts of radioactive trace plume caused by the explosion in 1953. To date, all the findings have been generalized. We present an integrated picture about accumulation of artificial radionuclides 137Cs, 90Sr, 239+240Pu and

  8. Statistical activities during 1976 and the design and initial analysis of nuclear site studies. [/sup 241/Am, /sup 137/Cs, /sup 239/Pu, /sup 240/Pu

    Energy Technology Data Exchange (ETDEWEB)

    Gilbert, R O; Essington, E H; Brady, D N; Doctor, P G; Eberhardt, L L

    1977-05-01

    Statistical design and analysis activities for the Nevada Applied Ecology Group (NAEG) during 1976 are briefly outlined. This is followed by a description of soil data collected thus far at nuclear study sites. Radionuclide concentrations in surface soil collected along a transect from ground zero (GZ) along the main fallout pattern are given for Nuclear Site (NS) 201. Concentrations in soil collected at 315 locations on a grid system at 200 foot spacings are also given for this site. The /sup 241/Am to /sup 137/Cs ratios change over NS 201 depending on location relative to GZ. They range from less than one where /sup 241/Am is at low levels, to more than fifty where /sup 241/Am levels are high (near GZ). The estimated median /sup 239/ /sup 240/Pu to /sup 241/Am ratio is 11 and appears to be relatively constant over the area (the 95 percent lower and upper limits on the true median ratio are about 8 and 14).

  9. Sequential leaching extraction of 239,240Pu, 238Pu, 241Pu and 241Am from a mud sample: An intercomparison study

    International Nuclear Information System (INIS)

    Full text: The determination of the association percentages of transuranics to different sediment phases could define their fate once they have been deposited onto the marine floor and their possible reactivity at the sediment/sea water interphase. Nowadays, there is a wide variety of leaching methods to extract transuranics from the different geochemical compounds conforming the sediments. Nevertheless, a general controversy is extended in the scientific world due to the extreme difficulty in testing their reliability, since the standards of transuranics linked to a certain sedimentary phase are not commercially available. Two mud subsamples taken from a storage container were analysed employing the same sequential extraction method, but with small handling differences.The following fractions were isolated: (1) Readily available (2) Carbonate bound and specifically adsorbed (3) Organically bound (4) Oxide and hydroxides bound and (5) residual. The 239,240Pu, 238Pu and 241Am extracted in each phase were analysed using standard radiochemical procedures. 241Pu was determined by both direct scintillation counting and through the 241Am in-growth up on the old disks containing Plutonium. The procedure for uncertainty calculations has been also included. (author)

  10. Sequential leaching extraction of 239,240Pu, 238Pu, 241Pu, 237Np and 241Am from a mud sample: An intercomparison study

    International Nuclear Information System (INIS)

    The transuranics content of a mud sample taken from a nuclear waste storage container was analysed employing two different sequential extraction methods. The following fractions were isolated: (1)Water soluble (2) Readily available (3) Carbonate bound and specifically adsorbed (4) Organically bound (5) Oxide and hydroxides bound and (6) residual. Both methods differ in the reagents employed, the extraction sequence applied as well as the temperature and means of extraction. The 239,240Pu, 238Pu, 237Np and 241Am extracted in each phase were determined using standard radiochemical procedures. 241Pu was analysed through the 241Am in-growth on just one old disk of the residual fraction containing plutonium. Plutonium was mainly associated to organic-oxides fractions (89-92 %). The percentage extracted in each fraction depended on the method and the extraction sequence used. The soluble fraction of plutonium was less than 13%. Neptunium seemed to be the more soluble than the other transuranics (27%) and the americium showed a tendency to be associated to carbonates (30%). (author)

  11. Updated estimates of /sup 239-240/Pu + 241Am inventory, spatial pattern, and soil tonnage for removal at nuclear site-201, NTS

    International Nuclear Information System (INIS)

    These new estimates are based on 712 241Am soil concentrations including 185 data values not previously available. Estimates were obtained using essentially the same kriging techniques and the estimated average /sup 239-240/Pu to 241Am ratio of 7.5 used to obtain previous results. The total Pu + Am inventory estimated to be in the top 5 cm of soil over the 109 hectare study is approximately 16.3 curies. Lower and upper limits on this inventory estimate are about 6.7 and 45.6 curies, respectively. It is estimated that about 58 acres (approx. = 23 hectares) of land in the study are contaminated at levels greater than 40 pCi/g which includes about 40 acres (approx. = 16 hectares) at levels greater than 160 pCi/g. Approximately 28,000 tons of soil would need to be removed (to 15-cm depth) to clean up all areas with estimated concentrates greater than or equal to 160 pCi/g. About 41,000 tons would require removal at the 40 pCi/g level. 5 references, 6 figures, 2 tables

  12. Estimation of covariances of {sup 10}B, {sup 11}B, {sup 55}Mn, {sup 240}Pu and {sup 241}Pu neutron nuclear data in JENDL-3.2

    Energy Technology Data Exchange (ETDEWEB)

    Shibata, Keiichi [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment; Nakajima, Yutaka; Murata, Toru

    1998-08-01

    Covariances of nuclear data have been estimated for 5 nuclides contained in JENDL-3.2. The nuclides considered are {sup 10}B, {sup 11}B, {sup 55}Mn, {sup 240}Pu, and {sup 241}Pu, which are regarded as important for the nuclear design study of fast reactors. The physical quantities for which covariances are deduced are cross sections, resolved and unresolved resonance parameters, and the first order Legendre-polynomial coefficient for the angular distribution of elastically scattered neutrons. The covariances were estimated by using the same methodology that had been used in the JENDL-3.2 evaluation in order to keep a consistency between mean values and their covariances. The least-squares fitting code GMA was used in estimating covariances for reactions of which JENDL-3.2 cross sections had been evaluated by taking account of measurements. Covariances of nuclear model calculations were deduced by the KALMAN system. The covariance data obtained were compiled in the ENDF-6 format, and will be put into the JENDL-3.2 Covariance File which is one of JENDL special purpose files. (author)

  13. Retention and translocation of foliar applied {sup 239,240}Pu and {sup 241}Am, as compared to {sup 137}Cs and {sup 85}Sr, into bean plants (Phaseolus vulgaris)

    Energy Technology Data Exchange (ETDEWEB)

    Henner, P. [Institute for Radioprotection and Nuclear Safety, Environment and Emergency Operations Division, Department for the Study of Radionuclides Behaviour in Ecosystems, Laboratory of Radioecology and Ecotoxicology, IRSN/DPRE/SECRE/LRE, Cadarache Centre, Building 186, BP 3, 13115 Saint-Paul-lez-Durance (France)]. E-mail: pascale.henner@irsn.fr; Colle, C. [Institute for Radioprotection and Nuclear Safety, Environment and Emergency Operations Division, Department for the Study of Radionuclides Behaviour in Ecosystems, Laboratory of Radioecology and Ecotoxicology, IRSN/DPRE/SECRE/LRE, Cadarache Centre, Building 186, BP 3, 13115 Saint-Paul-lez-Durance (France); Morello, M. [Institute for Radioprotection and Nuclear Safety, Environment and Emergency Operations Division, Department for the Study of Radionuclides Behaviour in Ecosystems, Laboratory of Radioecology and Ecotoxicology, IRSN/DPRE/SECRE/LRE, Cadarache Centre, Building 186, BP 3, 13115 Saint-Paul-lez-Durance (France)

    2005-07-01

    Foliar transfer of {sup 241}Am, {sup 239,240}Pu, {sup 137}Cs and {sup 85}Sr was evaluated after contamination of bean plants (Phaseolus vulgaris) at the flowering development stage, by soaking their first two trifoliate leaves into contaminated solutions. Initial retentions of {sup 241}Am (27%) and {sup 239,240}Pu (37%) were higher than those of {sup 137}Cs and {sup 85}Sr (10-15%). Mean fraction of retained activity redistributed among bean organs was higher for {sup 137}Cs (20.3%) than for {sup 239,240}Pu (2.2%), {sup 241}Am (1%) or {sup 85}Sr (0.1%). Mean leaf-to-pod translocation factors (Bq kg{sup -1}dry weight pod/Bq kg{sup -1}dry weight contaminated leaves) were 5.0 x 10{sup -4} for {sup 241}Am, 2.7 x 10{sup -6} for {sup 239,240}Pu, 5.4 x 10{sup -2} for {sup 137}Cs and 3.6 x 10{sup -4} for {sup 85}Sr. Caesium was mainly recovered in pods (12.8%). Americium and strontium were uniformly redistributed among leaves, stems and pods. Plutonium showed preferential redistribution in oldest bean organs, leaves and stems, and very little redistribution in forming pods. Results for americium and plutonium were compared to those of strontium and caesium to evaluate the consistency of the attribution of behaviour of strontium to transuranium elements towards foliar transfer, based on translocation factors, as stated in two radioecological models, ECOSYS-87 and ASTRAL.

  14. Retrospective determination of 238Pu, 239,240Pu and 90Sr activities in the outer bark of Norway spruce (Picea abies (L.) Karst.) collected at various sites in the Czech Republic

    International Nuclear Information System (INIS)

    The activity concentrations of 238Pu, 239,240Pu and 90Sr were determined in 25 archived spruce outer bark samples collected in coniferous forests across the Czech Republic in 1995. At three sampling sites the radionuclide activity concentrations were determined in forest soil. Data was provided on the cumulative deposition and vertical distribution of 238Pu, 239,240Pu and 90Sr in forest soil. The median activity concentration of 238Pu in the spruce bark samples was 0.009 Bq kg-1. The median activity concentration of 239,240Pu was 0.212 Bq kg-1, and the median activity concentration of 90Sr was 10.6 Bq kg-1. The radionuclide activity concentration distribution was not significantly explained by the local long-term (1961-2000) mean annual precipitation totals, by site elevation, by bark acidity, by soil moisture and soil texture. The activity concentrations of the radionuclides in bark were found to be higher than or comparable with the published and measured figures for radionuclide activity concentrations in cultivated and uncultivated soils (0-20 cm layer) in the Czech Republic and abroad. The activity concentration ratio of 90Sr/239,240Pu in the investigated spruce bark samples was higher than in the relevant soil samples. We assume that the crucial radioactive contamination loads in bark occurred in the first half of the 1960s, when the concentration of the investigated radionuclides in the air was highest. Spruce trunk bark has preserved relatively high activity concentrations of these radionuclides. The mechanism governing the long-term radionuclide activity concentrations in outer bark proportional to the local radioactive fallout rates is not correctly known. Our results indicate the suitability of spruce bark for use as an effective monitor of radioactive plume fallout loads even several decades after the contamination episode. (author)

  15. Ultra-trace determination of (90)Sr, (137)Cs, (238)Pu, (239)Pu, and (240)Pu by triple quadruple collision/reaction cell-ICP-MS/MS: Establishing a baseline for global fallout in Qatar soil and sediments.

    Science.gov (United States)

    Amr, Mohamed A; Helal, Abdul-Fattah I; Al-Kinani, Athab T; Balakrishnan, Perumal

    2016-03-01

    The development of practical, fast, and reliable methods for the ultra-trace determination of anthropogenic radionuclides (90)Sr, (137)Cs, (238)Pu, (239)Pu, and (240)Pu by triple quadruple collision/reaction cell inductively coupled plasma mass spectrometry (CRC-ICP-MS/MS) were investigated in term of its accuracy and precision for producing reliable results. The radionuclides were extracted from 1 kg of the environmental soil samples by concentrated nitric and hydrochloric acids. The leachate solutions were measured directly by triple quadrupole CRC-ICP-MS/MS. For quality assurance, a chemical separation of the concerned radionuclides was conducted and then measured by single quadrupole-ICP-MS. The developed methods were next applied to measure the anthropogenic radionuclides (90)Sr, (137)Cs, (238)Pu, (239)Pu, and (240)Pu in soil samples collected throughout the State of Qatar. The average concentrations of (90)Sr, (137)Cs, (238)Pu, (239)Pu, and (240)Pu were 0.606 fg/g (3.364 Bq/kg), 0.619 fg/g (2.038 Bq/kg), 0.034 fg/g (0.0195 Bq/kg), 65.59 fg/g (0.150 Bq/kg), and 12.06 fg/g (0.103 Bq/kg), respectively.

  16. Simultaneous determination of radiocesium ((135)Cs, (137)Cs) and plutonium ((239)Pu, (240)Pu) isotopes in river suspended particles by ICP-MS/MS and SF-ICP-MS.

    Science.gov (United States)

    Cao, Liguo; Zheng, Jian; Tsukada, Hirofumi; Pan, Shaoming; Wang, Zhongtang; Tagami, Keiko; Uchida, Shigeo

    2016-10-01

    Due to radioisotope releases in the Fukushima Dai-ichi Nuclear Power Plant (FDNPP) accident, long-term monitoring of radiocesium ((135)Cs and (137)Cs) and Pu isotopes ((239)Pu and (240)Pu) in river suspended particles is necessary to study the transport and fate of these long-lived radioisotopes in the land-ocean system. However, it is expensive and technically difficult to collect samples of suspended particles from river and ocean. Thus, simultaneous determination of multi-radionuclides remains as a challenging topic. In this study, for the first time, we report an analytical method for simultaneous determination of radiocesium and Pu isotopes in suspended particles with small sample size (1-2g). Radiocesium and Pu were sequentially pre-concentrated using ammonium molybdophosphate and ferric hydroxide co-precipitation, respectively. After the two-stage ion-exchange chromatography separation from the matrix elements, radiocesium and Pu isotopes were finally determined by ICP-MS/MS and SF-ICP-MS, respectively. The interfering elements of U ((238)U(1)H(+) and (238)U(2)H(+) for (239)Pu and (240)Pu, respectively) and Ba ((135)Ba(+) and (137)Ba(+) for (135)Cs and (137)Cs, respectively) were sufficiently removed with the decontamination factors of 1-8×10(6) and 1×10(4), respectively, with the developed method. Soil reference materials were utilized for method validation, and the obtained (135)Cs/(137)Cs and (240)Pu/(239)Pu atom ratios, and (239+240)Pu activities showed a good agreement with the certified/information values. In addition, the developed method was applied to analyze radiocesium and Pu in the suspended particles of land water samples collected from Fukushima Prefecture after the FDNPP accident. The (135)Cs/(137)Cs atom ratios (0.329-0.391) and (137)Cs activities (23.4-152Bq/g) suggested radiocesium contamination of the suspended particles mainly originated from the accident-released radioactive contaminates, while similar Pu contamination of suspended

  17. Simultaneous determination of radiocesium ((135)Cs, (137)Cs) and plutonium ((239)Pu, (240)Pu) isotopes in river suspended particles by ICP-MS/MS and SF-ICP-MS.

    Science.gov (United States)

    Cao, Liguo; Zheng, Jian; Tsukada, Hirofumi; Pan, Shaoming; Wang, Zhongtang; Tagami, Keiko; Uchida, Shigeo

    2016-10-01

    Due to radioisotope releases in the Fukushima Dai-ichi Nuclear Power Plant (FDNPP) accident, long-term monitoring of radiocesium ((135)Cs and (137)Cs) and Pu isotopes ((239)Pu and (240)Pu) in river suspended particles is necessary to study the transport and fate of these long-lived radioisotopes in the land-ocean system. However, it is expensive and technically difficult to collect samples of suspended particles from river and ocean. Thus, simultaneous determination of multi-radionuclides remains as a challenging topic. In this study, for the first time, we report an analytical method for simultaneous determination of radiocesium and Pu isotopes in suspended particles with small sample size (1-2g). Radiocesium and Pu were sequentially pre-concentrated using ammonium molybdophosphate and ferric hydroxide co-precipitation, respectively. After the two-stage ion-exchange chromatography separation from the matrix elements, radiocesium and Pu isotopes were finally determined by ICP-MS/MS and SF-ICP-MS, respectively. The interfering elements of U ((238)U(1)H(+) and (238)U(2)H(+) for (239)Pu and (240)Pu, respectively) and Ba ((135)Ba(+) and (137)Ba(+) for (135)Cs and (137)Cs, respectively) were sufficiently removed with the decontamination factors of 1-8×10(6) and 1×10(4), respectively, with the developed method. Soil reference materials were utilized for method validation, and the obtained (135)Cs/(137)Cs and (240)Pu/(239)Pu atom ratios, and (239+240)Pu activities showed a good agreement with the certified/information values. In addition, the developed method was applied to analyze radiocesium and Pu in the suspended particles of land water samples collected from Fukushima Prefecture after the FDNPP accident. The (135)Cs/(137)Cs atom ratios (0.329-0.391) and (137)Cs activities (23.4-152Bq/g) suggested radiocesium contamination of the suspended particles mainly originated from the accident-released radioactive contaminates, while similar Pu contamination of suspended

  18. Calculation of neutron cross sections for 90Zr, 208Pb and 209Bi in the energy range of 0.5-25 MeV by using the optical model potentials

    International Nuclear Information System (INIS)

    Neutron total cross sections and differential elastic scattering cross sections for the nuclides 90Zr, 208Pb and 209Bi were calculated using different global spherical optical potential (SOP) parameter sets at neutron energies from 0.5-25 MeV. Calculated cross sections for the corresponding nuclides were compared with their experimental data obtained by the EXFOR file to select the best fit parameter sets. It is found that the parameter sets of Ferer Rapaport for 90Zr and Bechetti and Greenless for 208Pb and 209Bi are the best fitted set to obtain the experimental data of total cross sections and angular distributions of these nuclides. (author)

  19. Seasonal and spatial variability of {sup 210}Po, {sup 238}U and {sup 239+240}Pu levels in the river catchment area assessed by application of neural-network based classification

    Energy Technology Data Exchange (ETDEWEB)

    Skwarzec, Bogdan [University of Gdansk, Faculty of Chemistry, Chair of Analytical Chemistry, 18/19 Sobieskiego Street, 80-952 Gdansk (Poland)], E-mail: bosk@chem.univ.gda.pl; Kabat, Krzysztof [University of Gdansk, Faculty of Chemistry, Chair of Analytical Chemistry, 18/19 Sobieskiego Street, 80-952 Gdansk (Poland); Astel, Aleksander [Pomeranian Academy, Biology and Environmental Protection Institute, Environmental Chemistry Research Unit, 22a Arciszewskiego Street, 76-200 Slupsk (Poland)

    2009-02-15

    The present study deals with the application of self-organizing maps (SOM) in order to model, classify and interpret seasonal and spatial variability of {sup 210}Po, {sup 238}U and {sup 239+240}Pu levels in the Vistula river basin. The data set represents concentration values for 3 alpha emitters ({sup 210}Po, {sup 238}U and {sup 239+240}Pu) measured in surface water samples collected at 19 different sampling locations (8 in major Vistula stream while 11 in right or left Vistula tributaries) during four seasons (winter, spring, summer and autumn) in the framework of a one-year quality monitoring study. The advantages of an SOM algorithm, its classification and visualization ability for environmental data sets, are stressed. The neural-network based classification made it possible to reveal specific patterns related to both seasonal and spatial variability. In the middle and upper part of Vistula catchment as well as in the right-shore tributaries, concentrations of {sup 210}Po and {sup 238}U during summer and winter are the lowest. Concentrations of {sup 210}Po and {sup 238}U increase significantly during spring and autumn in the Vistula river catchment, especially in the delta of Vistula river. High concentration of anthropogenic originated {sup 239+240}Pu indicates 'site-specific' character of pollution in two large left-shore tributaries located in the middle part of the Vistula drainage area. Efficient classification of sampling locations could lead to an optimization of river radiochemical sampling networks and to a better tracing of natural and anthropogenic changes along Vistula river stream.

  20. The damping of the single-particle proton strengths in 1isub(11/2) and 1jsub(15/2) states of 209Bi

    International Nuclear Information System (INIS)

    15 proton states have been mixed with the low-lying vibrational states as well as the vibrational states arising from the giant resonances in 208Pb to search for the broad fragmentations of the 1 'one' j15/2 and 'one' i11/2 states as observed in the most recent (α,t) reaction on 208Pb. The distribution of the shell-model strengths of these two high-spin states can be explained on the basis of the core polarisation effect on these two proton states of 209Bi. Knowledge of the altered shell-model energies of the proton states of 208Pb is necessary for the search for magicity in the superheavy nuclei. (author)

  1. Neutron-induced fission cross section of (nat)Pb and (209)Bi from threshold to 1 GeV: An improved parametrization

    CERN Document Server

    Tarrio, D; Audouin, L; Berthier, B; Duran, I; Ferrant, L; Isaev, S; Le Naour, C; Paradela, C; Stephan, C; Trubert, D; Abbondanno, U; Aerts, G; Alvarez-Velarde, F; Andriamonje, S; Andrzejewski, J; Assimakopoulos, P; Badurek, G; Baumann, P; Becvar, F; Belloni, F; Berthoumieux, E; Calvino, F; Calviani, M; Cano-Ott, D; Capote, R; Carrapico, C; Carrillo de Albornoz, A; Cennini, P; Chepel, V; Chiaveri, E; Colonna, N; Cortes, G; Couture, A; Cox, J; Dahlfors, M; David, S; Dillmann, I; Dolfini, R; Domingo-Pardo, C; Dridi, W; Eleftheriadis, C; Embid-Segura, M; Ferrari, A; Ferreira-Marques, R; Fitzpatrick, L; Frais-Koelbl, H; Fujii, K; Furman, W; Goncalves, I; Gonzalez-Romero, E; Goverdovski, A; Gramegna, F; Griesmayer, E; Guerrero, C; Gunsing, F; Haas, B; Haight, R; Heil, M; Herrera-Martinez, A; Igashira, M; Jericha, E; Kadi, Y; Kappeler, F; Karadimos, D; Karamanis, D; Kerveno, M; Ketlerov, V; Koehler, P; Konovalov, V; Kossionides, E; Krticka, M; Lampoudis, C; Leeb, H; Lederer, C; Lindote, A; Lopes, I; Losito, R; Lozano, M; Lukic, S; Marganiec, J; Marques, L; Marrone, S; Martinez, T; Massimi, C; Mastinu, P; Mendoza, E; Mengoni, A; Milazzo, P.M; Moreau, C; Mosconi, M; Neves, F; Oberhummer, H; O'Brien, S; Oshima, M; Pancin, J; Papachristodoulou, C; Papadopoulos, C; Patronis, N; Pavlik, A; Pavlopoulos, P; Perrot, L; Pigni, M.T; Plag, R; Plompen, A; Plukis, A; Poch, A; Praena, J; Pretel, C; Quesada, J; Rauscher, T; Reifarth, R; Rosetti, M; Rubbia, C; Rudolf, G; Rullhusen, P; Salgado, J; Santos, C; Sarchiapone, L; Sarmento, R; Savvidis, I; Tagliente, G; Tain, J.L; Tavora, L; Terlizzi, R; Vannini, G; Vaz, P; Ventura, A; Villamarin, D; Vlachoudis, V; Vlastou, R; Voss, F; Walter, S; Wendler, H; Wiescher, M; Wisshak, K

    2011-01-01

    Neutron-induced fission cross sections for (nat)Pb and (209)Bi were measured with a white-spectrum neutron source at the CERN Neutron Time-of-Flight (n\\_TOF) facility. The experiment, using neutrons from threshold up to 1 GeV, provides the first results for these nuclei above 200 MeV. The cross sections were measured relative to (235)U and (238)U in a dedicated fission chamber with parallel plate avalanche counter detectors. Results are compared with previous experimental data. Upgraded parametrizations of the cross sections are presented, from threshold energy up to 1 GeV. The proposed new sets of fitting parameters improve former results along the whole energy range.

  2. Comparison of reactions for the production of 258,257Db: 208Pb(51V,xn) and 209Bi(50Ti,xn)

    OpenAIRE

    Gates, Jacklyn M.

    2008-01-01

    Excitation functions for the 1n and 2n exit channels of the 208Pb(51V,xn)259-xDb reaction were measured. A maximum cross section of the 1n exit channel of 2070+1100/-760 pb was measured at an excitation energy of 16.0 +- 1.8 MeV. For the 2n exit channel, a maximum cross section of 1660+450/-370 pb was measured at 22.0 +- 1.8 MeV excitation energy. The 1n excitation function for the 209Bi(50Ti,n)258Db reaction was remeasured, resulting in a cross section of 5480+1750/-1370 pb at an excitati...

  3. Dynamical decay process of {sup 219,} {sup 220}Ra{sup *} formed in {sup 10,} {sup 11}B+{sup 209}Bi reactions

    Energy Technology Data Exchange (ETDEWEB)

    Sawhney, G.; Sharma, M.K. [Thapar University, School of Physics and Materials Science, Punjab (India)

    2012-05-15

    The excitation functions for both the evaporation residue and fission have been calculated for {sup 10}B +{sup 209}Bi and {sup 11}B+{sup 209}Bi reactions forming compound systems {sup 219,220}Ra{sup *}, using the dynamical cluster-decay model (DCM) with effects of deformations and orientations of the nuclei included in it. In addition to this, the excitation functions for complete fusion (CF) are obtained by summing the fission cross-sections, neutron evaporation and charged particle evaporation residue cross-sections produced through the {alpha}xn and pxn (x = 2, 3, 4) emission channels for the {sup 219}Ra system at various incident centre-of-mass energies. Experimentally the CF cross-sections are suppressed and the observed suppression is attributed to the low binding energy of {sup 10,11}B which breaks up into charged fragments. The reported complete fusion (CF) and incomplete fusion (ICF) excitation functions for the {sup 219}Ra system are found to be nicely fitted by the calculations performed in the framework of DCM, without invoking a significant contribution from quasi-fission. Although DCM has been applied for a number of compound nucleus decay studies in the recent past, the same is being used here in reference to ICF and subsequent decay processes along with the CF process. Interestingly the main contribution to complete fusion cross-section comes from the fission cross-section at higher incident energies, which in DCM is found to consist of an asymmetric fission window, shown to arise due to the deformation and orientation effects of formation and decay fragments. (orig.)

  4. Measurement of the Neutron Capture Cross Sections of $^{233}$U, $^{237}$Np, $^{240,242}$Pu, $^{241,243}$Am and $^{245}$Cm with a Total Absorption Calorimeter at n_TOF

    CERN Multimedia

    Beer, H; Wiescher, M; Cox, J; Rapp, W; Embid, M; Dababneh, S

    2002-01-01

    Accurate and reliable neutron capture cross section data for actinides are necessary for the poper design, safety regulation and precise performance assessment of transmutation devices such as Fast Critical Reactors or Accelerator Driven Systems (ADS). The goal of this proposal is the measurement of the neutron capture cross sections of $^{233}$U, $^{237}$Np, $^{240,242}$Pu, $^{241,243}$Am and $^{245}$Cm at n_TOF with an accuracy of 5~\\%. $^{233}$U plays an essential role in the Th fuel cycle, which has been proposed as a safer and cleaner alternative to the U fuel cycle. The capture cross sections of $^{237}$Np,$^{240,242}$Pu, $^{241,243}$Am and $^{245}$Cm play a key role in the design and optimization of a strategy for the Nuclear Waste Transmutation. A high accuracy can be achieved at n_TOF in such measurements due to a combination of features unique in the world: high instantaneous neutron fluence and excellent energy resolution of the facility, innovative Data Acquisition System based on flash ADCs and t...

  5. Determination of the neutron resonance parameters for 206Pb and of the thermal neutron capture cross section for 206Pb and 209Bi

    International Nuclear Information System (INIS)

    Chapter 1 describes the motivation of the measurements (accelerator driven systems, stellar nucleosynthesis, neutron induced reactions on 206Pb), the present status of the neutron capture data for 206Pb and 209Bi and the structure of this work. In Chapter 2 the basic reaction theory underlying this work is described. The neutron induced reaction mechanism and formalism are explained. The parameterisation of the cross section in terms of R-matrix theory is discussed and we put particular emphasis on the statistical behaviour of the resonance parameters and the impact of the angular distribution of gamma rays following neutron capture. The relation between experimental observables and the resonance parameters is discussed together with general comments related to resonance shape analysis. Chapter 3 is focused on the determination of resonance parameters for 206Pb. We performed high-resolution transmission and capture measurements at the Time-Of-Flight (TOF) facility GELINA of the IRMM at Geel (B) and determined the resonance parameters. For nuclei like 206Pb, where the total width is dominated by Γn, the capture area allows to determine G. Transmission measurements were carried out to determine Γn, and the statistical factor g of resonances. Before performing a Resonance Shape Analysis (RSA) on the transmission and capture data, we verified the neutron flux and resolution at GELINA. We also compared the characteristics of GELINA with those of the n-TOF facility at CERN. A special emphasis is placed on the total energy detection technique using C6D6 detectors. This technique was applied for the determination of the capture cross section. To reduce systematic bias effects on the capture cross section, the response of the detectors was determined by Monte Carlo simulations, which has been validated by experiments. Using these response functions the partial capture cross sections for individual resonances of 206Pb have been deduced, by unfolding the response of the C6D

  6. Seasonal variations in activity concentrations of 137Cs, 40K, 7Be, 228Ac, 99Tc, 90Sr, and 239/240Pu in Fucus vesiculosus and Ascophyllum nodosum from the South-Eastern coast of Norway

    International Nuclear Information System (INIS)

    Brown algae have been proven to be useful indicator organisms for heavy metals and radionuclides in the marine environments due to their ability to concentrate elements from the ambient water. There is quite a lot of data available on 137Cs in brown algae, especially for Fucus Vesiculosus. Fucus Vesiculosus is also commonly used to monitor the impact of the releases of 99Tc from the reprocessing plant in Sellafield. There is however a lack of data for other long-lived anthropogenic nuclides as 90Sr and Pu, and for natural occurring radionuclides. There is also a need for more knowledge about the mechanisms for uptake and accumulation of the different elements, and about different factors influencing the uptake. In this study activity concentrations of 137Cs, 40K, 7Be, 228Ac, 99Tc, 90Sr and 239/240Pu are measured in whole plants of Fucus vesiculosus and Ascophyllum nodosum collected over a period of one year from the south-eastern coast of Norway. Significant differences between the two species have been found. For 137Cs, 40K, 7Be, 228Ra and 239/240Pu, the activity concentrations were significantly higher in Fucus vesiculosus than in Ascophyllum nodosum, whereas for 99Tc the activity concentrations were higher in Ascophyllum nodosum than in Fucus vesiculosus. There were great seasonal variations in the concentrations of the measured radionuclides. For 99Tc there was also a difference in the temporal pattern for the two species. Possible uptake mechanisms will be discussed based on the results and on the known physiological differences between the two species. (author)

  7. Excitation functions of residual nuclei production from 40–2600 MeV proton-irradiated 206,207,208,natPb and 209Bi

    Indian Academy of Sciences (India)

    Yu E Titarenko; V F Batyaev; V M Zhivun; V O Kudryashov; K A Lipatov; A V Ignatyuk; S G Mashnik

    2007-02-01

    The work is aimed at experimental determination of the independent and cumulative yields of radioactive residual nuclei produced in intermediate-energy proton-irradiated thin targets made of highly isotopic enriched and natural lead (206,207,208,natPb) and 209Bi. 5972 radioactive product nuclide yields have been measured in 55 thin targets induced by 0.04, 0.07, 0.10, 0.15, 0.25, 0.6, 0.8, 1.2, 1.4, 1.6 and 2.6 GeV protons extracted from the ITEP U-10 proton synchrotron. The measured data have been compared with data obtained at other laboratories as well as with theoretical simulations by seven codes. We found that the predictive power of the tested codes is different but is satisfactory for most of the nuclides in the spallation region, though none of the codes agree well with the data in the whole mass region of product nuclides and all should be improved further.

  8. Modes of transference and rupture of the nucleus with neutron halos 6 He on 209 Bi near of the Coulomb barrier

    International Nuclear Information System (INIS)

    In recent experiments, the fusion of the exotic radioactive nucleus 6 He with 209 Bi has been studied for the first time at energies above and below the Coulomb barrier. A considerable enhancement in the fusion was observed, which implies a reduction of about 25% in the nominal fusion barrier. Some previous theoretical works suggest that this striking effect may be caused by the coupling to neutron transfer channels with a positive Q-value which would lead to a neutron flow and the consequent formation of a neck between the projectile and the target. Later, in the current work, we ran two new experiments on the same reaction using the FN Tandem Van de Graaff (10 MV) accelerator and the dual superconducting TwinSol system, both of them belonging to the University of Notre Dame, USA. This time, the purpose was to study one- and two-neutron transfer and the 6 He projectile breakup at laboratory energies of 14.7, 16.2, 17.9, 19.0 and 22.5 MeV. A strong group of 4 He was observed (with an effective Q-value about .5 MeV) whose integrated cross section results exceptionally high, exceeding the fusion cross section both above and below the barrier. The simultaneously measured elastic scattering angular distribution required high total cross sections so that this yield is confirmed. Preliminary coupled channels calculations sing the computer program called Fresco developed at the University of Surrey (England) suggested that the reaction mechanisms may be better described as a direct nuclear breakup and two-neutron transfer to unbound states in 211 Bi. These calculations predicted also an enhancement in the fusion cross section below the barrier due to the transfer and breakup channel coupling, which strongly suggests that this channel is the 'doorway state' that explains the fusion barrier reduction observed in previous experiments. It was found that the 4 He group fully dominates the total reaction cross section at the measured energies and we show evidence that a new

  9. Spatial distribution of {sup 241}Am, {sup 137}Cs, {sup 238}Pu, {sup 239,240}Pu and {sup 241}Pu over 17 year periods in the Ravenglass saltmarsh, Cumbria, UK

    Energy Technology Data Exchange (ETDEWEB)

    Oh, J.-S. [GAU-Radioanalytical, School of Ocean and Earth Science, National Oceanography Centre, Southampton SO14 3ZH (United Kingdom)], E-mail: jsoh@noc.soton.ac.uk; Warwick, P.E. [GAU-Radioanalytical, School of Ocean and Earth Science, National Oceanography Centre, Southampton SO14 3ZH (United Kingdom)], E-mail: pew@noc.soton.ac.uk; Croudace, I.W. [GAU-Radioanalytical, School of Ocean and Earth Science, National Oceanography Centre, Southampton SO14 3ZH (United Kingdom)], E-mail: iwc@noc.soton.ac.uk

    2009-07-15

    Ninety five surface scrape samples were collected at the Ravenglass saltmarsh and analysed for radionuclides by alpha spectrometry ({sup 238}Pu and {sup 239,240}Pu), gamma spectrometry ({sup 241}Am and {sup 137}Cs) and liquid scintillation counting ({sup 241}Pu). Both {sup 241}Am and {sup 137}Cs activities are compared with those reported by Horrill [1983. Concentrations and spatial distribution of radioactivity in an ungrazed saltmarsh. In: Coughtrey, P.J. (Ed.), Ecological Aspects of Radionuclide Release. British Ecological Society Special Publication No. 3. Blackwell, Oxford, pp. 119-215.] Significant decreases in activities for both radionuclides were observed which is caused by the declining levels of discharges from the Sellafield nuclear reprocessing plant since the 1980s. It has been concluded that the spatial distribution of these radionuclides are controlled by the tidal currents and the clay contents in the sediments. There is evidence of surface erosion of the saltmarsh and redistribution of radionuclides in the saltmarsh using isotopic ratios of measured Pu.

  10. Accumulation of polonium 210Po, uranium (234U and 238U and plutonium (238Pu and 239+240Pu in tissues and organs of deer Carvidae from northern Poland

    Directory of Open Access Journals (Sweden)

    Strumińska-Parulska D. I.

    2013-04-01

    Full Text Available Livers, kidneys and muscles of large herbivorous animals: roe deer (Capreolus capreolus, red deer (Cervus elaphus and fallow deer (Dama dama, collected in northern Poland, were the subject of the investigation. Polonium, uranium and plutonium activities were measured using alpha spectrometry along with relevant radiochemical procedures. The average concentrations of 210Po ranged between 0.02±0.01 Bq kg−1 ww in muscles and 7.15±0.12 Bq kg−1 ww in kidneys. The concentration of 238U ranged widely between 2.49±0.18 and 69.37±5.45 mBq kg−1 ww. The average concentrations of 239+240Pu ranged between 0.18±0.04 mBq kg−1 ww in muscle and 2.77±0.60 mBq kg−1 ww in kidneys. Statistical analysis showed that the sampling location, sex, age and species did not influence on the radioisotope activities in the analyzed samples.

  11. Modes of transference and rupture of the nucleus with neutron halos {sup 6} He on {sup 209} Bi near of the Coulomb barrier; Modos de transferencia y rompimiento del nucleo con halo neutronico {sup 6} He sobre {sup 209} Bi cerca de la barrera de Coulomb

    Energy Technology Data Exchange (ETDEWEB)

    Lizcano C, D

    2003-07-01

    In recent experiments, the fusion of the exotic radioactive nucleus {sup 6} He with {sup 209} Bi has been studied for the first time at energies above and below the Coulomb barrier. A considerable enhancement in the fusion was observed, which implies a reduction of about 25% in the nominal fusion barrier. Some previous theoretical works suggest that this striking effect may be caused by the coupling to neutron transfer channels with a positive Q-value which would lead to a neutron flow and the consequent formation of a neck between the projectile and the target. Later, in the current work, we ran two new experiments on the same reaction using the FN Tandem Van de Graaff (10 MV) accelerator and the dual superconducting TwinSol system, both of them belonging to the University of Notre Dame, USA. This time, the purpose was to study one- and two-neutron transfer and the {sup 6} He projectile breakup at laboratory energies of 14.7, 16.2, 17.9, 19.0 and 22.5 MeV. A strong group of {sup 4} He was observed (with an effective Q-value about .5 MeV) whose integrated cross section results exceptionally high, exceeding the fusion cross section both above and below the barrier. The simultaneously measured elastic scattering angular distribution required high total cross sections so that this yield is confirmed. Preliminary coupled channels calculations sing the computer program called Fresco developed at the University of Surrey (England) suggested that the reaction mechanisms may be better described as a direct nuclear breakup and two-neutron transfer to unbound states in {sup 211} Bi. These calculations predicted also an enhancement in the fusion cross section below the barrier due to the transfer and breakup channel coupling, which strongly suggests that this channel is the 'doorway state' that explains the fusion barrier reduction observed in previous experiments. It was found that the {sup 4} He group fully dominates the total reaction cross section at the

  12. Measurements of delayed neutrons yields and time spectra from 1 GeV protons interacting with thick {sup nat}Pb, {sup 209}Bi and {sup nat}Fe targets

    Energy Technology Data Exchange (ETDEWEB)

    Ridikas, D.; Blideanu, V.; David, J.C.; Dore, D.; Prevost, A. [CEA Saclay, Dept. d' Astrophysique, de Physique des Particules de Physique Nucleaire et de l' Instrumentation Associee, 91- Gif sur Yvette (France); Ledoux, X. [CEA Bruyeres-le-Chatel (CEA/DIF, DPTA/SPN), 91 (France); Barzakh, A.; Fedorov, D.; Moroz, F.; Panteleev, V.; Shcherbakov, O.; Vorobyev, A. [Petersburg Nuclear Physics Institute, Leningrad district (Russian Federation); Plukiene, R.; Plukis, A. [Institute of Physics, Vilnius (Lithuania)

    2008-07-01

    This paper presents the experimental results on the delayed neutrons (DN) yields and time spectra from 1 GeV protons interacting with natural lead, {sup 209}Bi and natural iron targets of variable thicknesses from 5 cm to 55 cm. Both absolute yields and time constants were obtained. In parallel, the MCNPX and PHITS codes were used to predict the DN precursors and construct the theoretical DN tables. Different model parameters are examined and show significant dependence on the choice of the intra-nuclear cascade and fission-evaporation models used. These data and modelling are of great importance for the new generation spallation neutron sources based on liquid metal technologies. Finally, the above experiment allowed the determination of the production cross sections of a number of delayed neutrons precursors as, {sup 87}Br, {sup 88}Br and {sup 17}N. For the 3 targets the emission of delayed neutrons is dominated by light reaction products such as {sup 9}Li and {sup 17}N during decay times from 0 to 20-30 s. In the case of fissile targets after longer decay times the fission fragments such as {sup 88}Br and {sup 87}Br are the major contributors. These results permit the examination of two different reaction mechanisms, namely fission and fragmentation, implemented in high energy transport codes. (authors)

  13. Simultaneous measurement of {sup 239}Pu, {sup 240}Pu, {sup 241}Pu, and {sup 242}Pu by high resolution inductively coupled plasma mass spectrometer (HR ICP-MS) in marine sediments; Mesure des isotopes du plutonium des sediments marins par spectrometrie de masse a plasma couple inductivement haute resolution (HR ICP-MS)

    Energy Technology Data Exchange (ETDEWEB)

    Bruneau, F

    1999-07-01

    Transuranics elements are of particular interest in radioecological studies because of their radiotoxicity and their potential use to decipher source fingerprints and transport processes. The simultaneous measurement of {sup 239}Pu, {sup 240}Pu, {sup 241}Pu, and {sup 242}Pu in environmental samples requires a specific chemical procedure. This work deals with an analytical procedure which yields a very high grade of purification of Pu suitable for ultra low level detection by HR ICP-MS, from marine sediments. After the elimination of major elements (Fe, Al, Mg...) by a first chromatographic separation, a new device of purification by solvent extraction and concentration by a second chromatographic separation is used to obtain a concentrated and high purified solution of plutonium. The chemical procedure have been validated on IAEA certified sediment samples and on sediment samples collected in the roads of Cherbourg which had been previously analysed by other techniques (a spectrometry and thermo-ionisation mass spectrometer). (author)

  14. Seasonal variations in activity concentrations of {sup 137}Cs, {sup 40}K, {sup 7}Be, {sup 228}Ac, {sup 99}Tc, {sup 90}Sr, and {sup 239/240}Pu in Fucus vesiculosus and Ascophyllum nodosum from the South-Eastern coast of Norway

    Energy Technology Data Exchange (ETDEWEB)

    Raaum, A.; Christensen, G.C. [Institute for Energy Technology, Health and Safety Dept., Kjeller (Norway)

    2004-07-01

    Brown algae have been proven to be useful indicator organisms for heavy metals and radionuclides in the marine environments due to their ability to concentrate elements from the ambient water. There is quite a lot of data available on {sup 137}Cs in brown algae, especially for Fucus Vesiculosus. Fucus Vesiculosus is also commonly used to monitor the impact of the releases of {sup 99}Tc from the reprocessing plant in Sellafield. There is however a lack of data for other long-lived anthropogenic nuclides as {sup 90}Sr and Pu, and for natural occurring radionuclides. There is also a need for more knowledge about the mechanisms for uptake and accumulation of the different elements, and about different factors influencing the uptake. In this study activity concentrations of {sup 137}Cs, {sup 40}K, {sup 7}Be, {sup 228}Ac, {sup 99}Tc, {sup 90}Sr and {sup 239/240}Pu are measured in whole plants of Fucus vesiculosus and Ascophyllum nodosum collected over a period of one year from the south-eastern coast of Norway. Significant differences between the two species have been found. For {sup 137}Cs, {sup 40}K, {sup 7}Be, {sup 228}Ra and {sup 239/240}Pu, the activity concentrations were significantly higher in Fucus vesiculosus than in Ascophyllum nodosum, whereas for {sup 99}Tc the activity concentrations were higher in Ascophyllum nodosum than in Fucus vesiculosus. There were great seasonal variations in the concentrations of the measured radionuclides. For {sup 99}Tc there was also a difference in the temporal pattern for the two species. Possible uptake mechanisms will be discussed based on the results and on the known physiological differences between the two species. (author)

  15. Motivation for New Measurements on 241, 242, 243Am Isotopes

    International Nuclear Information System (INIS)

    The initial objective of this work was an updated review on the Am isotopes data since the next official release (3.1) of the JEFF3 evaluated data file is foreseen around June 2005. Alternatively, this work searches for the possible reasons of the observed discrepancies between differential and integral measurement results. In particular, strong differences are encountered on σγth values and epithermal branching ratio values for the 241Am. Although the JEF2.2 validation is used as guide in parallel with a systematic study of all differential and integral results available, the need for new measurements clearly shows up. This paper finally draws up a list of desired and feasible new differential and integral measurements on the Am isotopes

  16. 232Th、233U、238Pu、240Pu、242Pu、241Am、242Cm、243Cm和244Cm的裂变释放热能研究%Thermal Energy Released in Fission of 232 Th,233 U,238 Pu, 240 Pu,242 Pu,241 Am,242 Cm,243 Cm and 244 Cm

    Institute of Scientific and Technical Information of China (English)

    赵艳飞; 马续波; 陈义学

    2013-01-01

    In the nuclear reactor design ,the precise calculation of thermal fission energy is of great significance .In the pressurized water reactor ,high energy neutron-induced fission rarely occurs ,the isotopes including 233 U ,241 Am and 243 Cm are mostly induced by thermal neutrons ,while the other isotopes such as 232Th ,238Pu ,240Pu ,242Pu ,242Cm and 244 Cm are by fast neutron . In order to carry out this work , the nuclear data extracted from the latest evaluated nuclear data file (ENDF/B-Ⅶ ) were adopted ,and the energy-conservation law for the calculation of total fission energy were used , meanw hile ,with the consideration of capture energy and the correction of βand γ ,the thermal fission energy of nine isotopes was obtained .Compared with the data excerpted from IAEA issued WIMS-D database ,the results are reasonable .The thermal fission energy and its uncertainties of the nine isotopes are :(193.939 ± 0.176) MeV for 232 Th , (200.063 ± 0.084) MeV for 233 U ,(208.786 ± 1.133 ) MeV for 238 Pu ,(211.266 ± 0.220 ) MeV for 240 Pu ,(213.862 ± 0.299 ) MeV for 242 Pu ,(215.077 ± 0.210 ) MeV for 241 Am ,(218.821 ± 0.159) MeV for 242Cm ,(218.525 ± 0.388) MeV for 243Cm ,and (220.067 ± 0.131) MeV for 244 Cm ,respectively .%在核反应堆设计中,对每次裂变释放热能进行精确计算具有重要意义。在压水堆内,高能中子诱发核裂变份额很小,233 U、241 Am、243 Cm主要由热中子诱发裂变,232 T h、238 Pu、240 Pu、242 Pu、242 Cm、244 Cm主要由快中子诱发裂变。本文采用最新的核评价数据库 ENDF/B-Ⅶ,利用质量守恒法计算裂变释放总能,同时研究了中微子带走的能量,中子俘获能及β、γ修正项,最终给出了9种核素裂变释放热能。与IAEA颁布的WIMS-D格式数据库中的裂变释放热能数据的对比表明,本文所用方法计算结果合理。9种核素每次裂变释放热能分别为:232 Th ,(193.939±0.176) MeV ;233 U ,(200.063

  17. 239 240Pu in Lake Michigan: 1971 to 1978

    International Nuclear Information System (INIS)

    The plutonium concentration data presented previously have consisted primarily of results from studies of short-term variations, i.e., the annual plutonium cycle conducted at Lake Michigan station ANL-5, 12 km SW of Grand Haven, Michigan. In this report, mean annual concentrations of total plutonium in unfiltered water from far off-shore (> 30 km) stations for the period 1971 through 1977, and from station ANL-5 (1975 through 1978) are summarized to establish the long-term trend in plutonium concentration in Lake Michigan. The results presented show that the mean annual concentration in the water column is similar at ANL-5 and at offshore stations and has decreased at the rate of only 6% per year during the period 1972 through 1978. The nearly constant concentration indicates that steady-state equilibria exist between plutonium inputs to the lake and the loss of plutonium from the water column. Observations suggest the existence of an active redox cycle for Pu in Lake Michigan. In this cycle, Pu IV atoms in solution are continually taken up by particulate materials but may be oxidized within microzones of the particles such as freshly deposited manganese coatings and also in solution by agents such as dissolved oxygen. In turn, the concentration of Pu VI in solution may be limited by reaction with reducing constituents of the coloidal-sized fraction (or decomposer organisms such as bacteria or fungi, which might have been present after filtration) and with planktonic organisms in the environment to produce Pu IV and thus maintain the cycle

  18. Laser spectroscopy of the ground state hyperfine splittings of $^{209}$Bi$^{82+}$ and $^{209}$Bi$^{80+}$

    CERN Document Server

    Lochmann, Matthias; Geppert, Christopher; Andelkovic, Zoran; Anielski, Denis; Botermann, Benjamin; Bussmann, Michael; Dax, Andreas; Frömmgen, Nadja; Hammen, Michael; Hannen, Volker; Kühl, Thomas; Litvinov, Yuri A; López-Coto, Rubén; Stöhlker, Thomas; Thompson, Richard C; Vollbrecht, Jonas; Volotka, Andrey; Weinheimer, Christian; Wen, Weiqiang; Will, Elisa; Winters, Danyal; Sánchez, Rodolfo; Nörtershäuser, Wilfried

    2014-01-01

    We performed a laser spectroscopic determination of the $2s$ hyperfine structure (HFS) splitting of lithiumlike $^{209}\\text{Bi}^{80+}$ for the first time and repeated the measurement of the $1s$ HFS splitting of hydrogenlike $^{209}\\text{Bi}^{82+}$. Both ion species were subsequently stored in the Experimental Storage Ring at GSI and cooled with an electron cooler at a velocity of $\\approx 0.71\\,c$. Pulsed laser excitation of the M1 HFS-transition was performed in anticollinear and collinear geometry for $^{209}\\text{Bi}^{82+}$ and $^{209}\\text{Bi}^{80+}$, respectively, and observed by fluorescence detection. We obtain $\\Delta E^{(1s)}= 5086.3(11)\\,\\textrm{meV}$ for $^{209}\\text{Bi}^{82+}$ and $\\Delta E^{(2s)}= 797.50(18)\\,\\textrm{meV}$ for $^{209}\\text{Bi}^{80+}$. A specific difference between the two splitting energies can be used to test QED calculations in the strongest static magnetic fields available in the laboratory independent of nuclear structure effects. Our results confirm the large relativistic ...

  19. New measurement of neutron capture resonances of 209Bi

    CERN Document Server

    Domingo-Pardo, C; Abbondanno, U; Aerts, G; Alvarez-Pol, H; Alvarez-Velarde, F; Andriamonje, Samuel A; Andrzejewski, J; Assimakopoulos, Panayiotis; Audouin, L; Badurek, G; Baumann, P; Becvar, F; Berthoumieux, E; Calviño, F; Cano-Ott, D; Capote, R; Carrillode Albornoz, A; Cennini, P; Chepel, V; Chiaveri, Enrico; Colonna, N; Cortés, G; Couture, A; Cox, J; Dahlfors, M; David, S; Dillman, I; Dolfini, R; Dridi, W; Durán, I; Eleftheriadis, C; Embid-Segura, M; Ferrant, L; Ferrari, A; Ferreira-Marques, R; Fitzpatrick, L; Frais-Kölbl, H; Fujii, K; Furman, W; Gallino, R; Gonçalves, I; Gonzalez-Romero, E; Goverdovski, A; Gramegna, F; Griesmayer, E; Guerrero, C; Gunsing, F; Haas, B; Haight, R; Heil, M; Herrera-Martínez, A; Igashira, M; Isaev, S; Jericha, E; Kadi, Y; Kappeler, F; Karamanis, D; Karadimos, D; Kerveno, M; Ketlerov, V; Köhler, P; Konovalov, V; Kossionides, E; Krticka, M; Lamboudis, C; Leeb, H; Lindote, A; Lopes, I; Lozano, M; Lukic, S; Marganiec, J; Marques, L; Marrone, S; Mastinu, P; Mengoni, A; Milazzo, P M; Moreau, C; Mosconi, M; Neves, F; Oberhummer, Heinz; Oshima, M; O'Brien, S; Pancin, J; Papachristodoulou, C; Papadopoulos, C; Paradela, C; Patronis, N; Pavlik, A; Pavlopoulos, P; Perrot, L; Plag, R; Plompen, A; Plukis, A; Poch, A; Pretel, C; Quesada, J; Rauscher, T; Reifarth, R; Rosetti, M; Rubbia, Carlo; Rudolf, G; Rullhusen, P; Salgado, J; Sarchiapone, L; Savvidis, I; Stéphan, C; Tagliente, G; Taín, J L; Tassan-Got, L; Tavora, L; Terlizzi, R; Vannini, G; Vaz, P; Ventura, A; Villamarín, D; Vincente, M C; Vlachoudis, V; Vlastou, R; Voss, F; Walter, S; Wendler, H; Wiescher, M; Wisshak, K

    2006-01-01

    The neutron capture cross section of Bi209 has been measured at the CERN n TOF facility by employing the pulse-height-weighting technique. Improvements over previous measurements are mainly because of an optimized detection system, which led to a practically negligible neutron sensitivity. Additional experimental sources of systematic error, such as the electronic threshold in the detectors, summing of gamma-rays, internal electron conversion, and the isomeric state in bismuth, have been taken into account. Gamma-ray absorption effects inside the sample have been corrected by employing a nonpolynomial weighting function. Because Bi209 is the last stable isotope in the reaction path of the stellar s-process, the Maxwellian averaged capture cross section is important for the recycling of the reaction flow by alpha-decays. In the relevant stellar range of thermal energies between kT=5 and 8 keV our new capture rate is about 16% higher than the presently accepted value used for nucleosynthesis calculations. At th...

  20. ZPR-6 assembly 7 high {sup 240} PU core : a cylindrical assemby with mixed (PU, U)-oxide fuel and a central high {sup 240} PU zone.

    Energy Technology Data Exchange (ETDEWEB)

    Lell, R. M.; Schaefer, R. W.; McKnight, R. D.; Tsiboulia, A.; Rozhikhin, Y.; Nuclear Engineering Division; Inst. of Physics and Power Engineering

    2007-10-01

    Over a period of 30 years more than a hundred Zero Power Reactor (ZPR) critical assemblies were constructed at Argonne National Laboratory. The ZPR facilities, ZPR-3, ZPR-6, ZPR-9 and ZPPR, were all fast critical assembly facilities. The ZPR critical assemblies were constructed to support fast reactor development, but data from some of these assemblies are also well suited to form the basis for criticality safety benchmarks. Of the three classes of ZPR assemblies, engineering mockups, engineering benchmarks and physics benchmarks, the last group tends to be most useful for criticality safety. Because physics benchmarks were designed to test fast reactor physics data and methods, they were as simple as possible in geometry and composition. The principal fissile species was {sup 235}U or {sup 239}Pu. Fuel enrichments ranged from 9% to 95%. Often there were only one or two main core diluent materials, such as aluminum, graphite, iron, sodium or stainless steel. The cores were reflected (and insulated from room return effects) by one or two layers of materials such as depleted uranium, lead or stainless steel. Despite their more complex nature, a small number of assemblies from the other two classes would make useful criticality safety benchmarks because they have features related to criticality safety issues, such as reflection by soil-like material. The term 'benchmark' in a ZPR program connotes a particularly simple loading aimed at gaining basic reactor physics insight, as opposed to studying a reactor design. In fact, the ZPR-6/7 Benchmark Assembly (Reference 1) had a very simple core unit cell assembled from plates of depleted uranium, sodium, iron oxide, U3O8, and plutonium. The ZPR-6/7 core cell-average composition is typical of the interior region of liquid-metal fast breeder reactors (LMFBRs) of the era. It was one part of the Demonstration Reactor Benchmark Program,a which provided integral experiments characterizing the important features of demonstration-size LMFBRs. As a benchmark, ZPR-6/7 was devoid of many 'real' reactor features, such as simulated control rods and multiple enrichment zones, in its reference form. Those kinds of features were investigated experimentally in variants of the reference ZPR-6/7 or in other critical assemblies in the Demonstration Reactor Benchmark Program.

  1. Electrochemical oxidation of 243Am(III) in nitric acid by a terpyridyl-derivatized electrode

    Energy Technology Data Exchange (ETDEWEB)

    Dares, C. J.; Lapides, A. M.; Mincher, B. J.; Meyer, T. J.

    2015-11-05

    A high surface area, tin-doped indium oxide electrode surface-derivatized with a terpyridine ligand has been applied to the oxidation of trivalent americium to Am(V) and Am(VI) in nitric acid. Potentials as low as 1.8 V vs. the saturated calomel electrode are used, 0.7 V lower than the 2.6 V potential for one-electron oxidation of Am(III) to Am(IV) in 1 M acid. This simple electrochemical procedure provides, for the first time, a method for accessing the higher oxidation states of Am in non-complexing media for developing the coordination chemistries of Am(V) and Am(VI) and, more importantly, for separation of americium from nuclear waste streams.

  2. Semi-empirical Calculation for Yield of 240Pu Spontaneous Fission

    Institute of Scientific and Technical Information of China (English)

    SHU; Neng-chuan; LIU; Li-le; CHEN; Xiao-song; LIU; Ting-jin; SUN; Zheng-jun; CHEN; Yong-jing; QIAN; Jing

    2012-01-01

    <正>The spontaneous fission yield has important implication in the nuclear engineering. This work used semi-empirical model to calculate its chain yield, the result shows good agreement with the measured data. There are only 3 sets of measured data, and only too gave the chain yields and cumulative yields, covering 17 chains. It is not enough to satisfy the requirement of users. So it is needed to use theoretical model to calculate the chain yield without measured data.

  3. CALORIMETER-BASED ADJUSTMENT OF MULTIPLICITY DETERMINED 240PU EFF KNOWN-A ANALYSIS FOR THE ASSAY OF PLUTONIUM

    Energy Technology Data Exchange (ETDEWEB)

    Dubose, F.

    2012-02-21

    In nuclear material processing facilities, it is often necessary to balance the competing demands of accuracy and throughput. While passive neutron multiplicity counting is the preferred method for relatively fast assays of plutonium, the presence of low-Z impurities (fluorine, beryllium, etc.) rapidly erodes the assay precision of passive neutron counting techniques, frequently resulting in unacceptably large total measurement uncertainties. Conversely, while calorimeters are immune to these impurity effects, the long count times required for high accuracy can be a hindrance to efficiency. The higher uncertainties in passive neutron measurements of impure material are driven by the resulting large (>>2) {alpha}-values, defined as the ({alpha},n):spontaneous fission neutron emission ratio. To counter impurity impacts for high-{alpha} materials, a known-{alpha} approach may be adopted. In this method, {alpha} is determined for a single item using a combination of gamma-ray and calorimetric measurements. Because calorimetry is based on heat output, rather than a statistical distribution of emitted neutrons, an {alpha}-value determined in this way is far more accurate than one determined from passive neutron counts. This fixed {alpha} value can be used in conventional multiplicity analysis for any plutonium-bearing item having the same chemical composition and isotopic distribution as the original. With the results of single calorimeter/passive neutron/gamma-ray measurement, these subsequent items can then be assayed with high precision and accuracy in a relatively short time, despite the presence of impurities. A calorimeter-based known-{alpha} multiplicity analysis technique is especially useful when requiring rapid, high accuracy, high precision measurements of multiple plutonium bearing items having a common source. The technique has therefore found numerous applications at the Savannah River Site. In each case, a plutonium (or mixed U/Pu) bearing item is divided into multiple containers. A single item from that batch is then selected for both neutron and calorimetric measurements; all remaining items undergo a neutron measurement only. Using the technique mentioned above, the 'true' {alpha} value determined from the first (calorimeter and passive neutron measured) item is used in multiplicity analysis for all other items in the batch. The justification for using this {alpha} value in subsequent calculations is the assumption that the chemical composition and isotopic distribution of all batch items are the same, giving a constant ({alpha},n):spontaneous fission ratio. This analysis method has been successfully applied to the KIS Facility, significantly improving measurement uncertainties and reducing processing times for numerous items. Comprehensive plans were later developed to extend the use of this method to other applications, including the K-Area Shuffler and the H-Area Pu-Blending Project. While only the feasibility study for the Shuffler has been completed, implementation of the method in the H-Area Pu-Blending Project is currently in progress and has been successfully applied to multiple items. This report serves to document the details of this method in order to serve as a reference for future applications. Also contained herein are specific examples of the application of known-{alpha} multiplicity analysis.

  4. Determination of 238Pu and 239+240Pu in soils of different agricultural regions of Guatemala

    International Nuclear Information System (INIS)

    This study allowed to determine the concentration of radioactivity alpha, due to contamination for plutonium in cultivated soils of different regions of Guatemala. They were carried out samplings for convenience in cultivated soils of 15 departments of the republic, determined in each soils sample, the activity concentration for plutonium 238Plutonium and 239+240Plutonium expressed in mili-becquerel by kilogram (mBq/Kg), which has been caused from all over the world by the different provoked liberations or accidents of radioactive particles to the atmosphere

  5. 242Pu as tracer for simultaneous determination of 237Np and 239,240Pu in environmental samples

    DEFF Research Database (Denmark)

    Chen, Q.J.; Dahlgaard, H.; Nielsen, S.P.;

    2002-01-01

    A procedure has been developed using Pu-242 as tracer for simultaneous determination of Np-237 and Pu-239,Pu-240 in environmental samples. The validity of the method has been demonstrated by ICPMS and alpha-spectroscopy for up to 10 gram soil and sediment, seawater up to 200 litres. The paper...... describes a suitable chemical procedure for Np and Pu including a quantitative pre-concentration of neptunium and plutonium, preparation of Np4+ and Pu4+, NP(NO3)(6)(2-) and Pu(NO3)(6)(2-), The ratio of Np-237/Pu-242 (or Np-237/Pu-239) before and after the procedure has been determined using 10 g soil (free...... from Np and Pu) R-before/R-after = 1.004 +/- 3.3% (S.D n = 20) and 1 litre seawater R-before/R-after = 1.019+/-1.9% (S.D., n = 12). Results from the intercomparison samples LAEA-135, LAEA-381 and from environmental samples are presented....

  6. Procedures for determination of 239,240Pu, 241Am, 237Np, 234,238U, 2

    DEFF Research Database (Denmark)

    Chen, Q.J.; Aarkrog, Asker; Nielsen, Sven Poul;

    2001-01-01

    Since 1987, the Department of Nuclear Safety Research, Risø National Laboratory has developed procedures for analysis of low-level amounts of radioactivity in large samples of 200 liters seawater, 10 gram sediment, soil and other environmental materials.These analytical procedures provide high ch...

  7. Measurement of neutron total cross-sections of 209Bi at the Pohang Neutron Facility

    CERN Document Server

    Wang, Tao-Feng; Kim, Guinyun

    2014-01-01

    Measurements of neutron total cross-sections of natural bismuth in the neutron energy region from 0.1 eV to 100 eV have been performed by using the time-of-flight method at the Pohang Neutron Facility, which consists of an electron linear accelerator, a water-cooled tantalum target with a water moderator, and a 12-m-long time-of-flight path. A 6Li-ZnS(Ag) scintillator with a diameter of 12.5 cm and a thickness of 1.6 cm is employed as a neutron detector, and a piece of high purity natural bismuth metallic plates with a thickness of 3 mm is used for the neutron transmission measurement. The present results were compared with the evaluated data from ENDF/B VII.1 and other previous reported experimental data.

  8. Fission fragment mass distribution studies for 28Si + 197Au, 209Bi, 235U reactions

    International Nuclear Information System (INIS)

    In reactions with heavy ions, complete fusion and quasi-fission are the competing processes at energies above the Coulomb barrier. The quasi-fission process, in which the system reseparates before reaching a compact compound nucleus, is a major hurdle in forming heavy and superheavy evaporation residues (ER) in heavy-ion reactions. Fission fragment mass distribution for the fully equilibrated compound nucleus is decided at the scission point due to a long descent from saddle to scission. At higher excitation energies, the shell effects are washed out and the mass distribution is expected to be symmetric. The width of the distribution strongly depends on the entrance channel properties, such as mass asymmetry, deformation of interacting nuclei, collision energy, and the Coulomb factor Z1 Z2. Any sudden change in the width of the mass distribution would indicate departure from full equilibration, while onset of mass asymmetry or a sudden increase in width would be a strong signal of quasi fission

  9. Determination of 236U and transuranium elements in depleted uranium ammunition by α-spectrometry and ICP-MS

    International Nuclear Information System (INIS)

    It is well known that ammunition containing depleted uranium (DU) was used by NATO during the Balkan conflict. To evaluate the origin of DU (the enrichment of natural uranium or the reprocessing of spent nuclear fuel) it is necessary to directly detect the presence of activation products (236U, 239Pu, 240Pu, 241Am, and 237Np) in the ammunition. In this work the analysis of actinides by α-spectrometry was compared with that by inductively coupled plasma mass spectrometry (ICP-MS) after selective separation of ultratraces of transuranium elements from the uranium matrix. 242Pu and 243Am were added to calculate the chemical yield. Plutonium was separated from uranium by extraction chromatography, using tri-n-octylamine (TNOA), with a decontamination factor higher than 106; after elution plutonium was determined by ICP-MS (239Pu and 240Pu) and α-spectrometry (239+240Pu) after electroplating. The concentration of Pu in two DU penetrator samples was 7 x 10-12 g g-1 and 2 x 10-11 g g-1. The 240Pu/239Pu isotope ratio in one penetrator sample (0.12±0.04) was significantly lower than the 240Pu/239Pu ratios found in two soil samples from Kosovo (0.35±0.10 and 0.27±0.07). 241Am was separated by extraction chromatography, using di(2-ethylhexyl)phosphoric acid (HDEHP), with a decontamination factor as high as 107. The concentration of 241Am in the penetrator samples was 2.7 x 10-14 g g-1 and -15 g g-1. In addition 237Np was detected at ultratrace levels. In general, ICP-MS and α-spectrometry results were in good agreement.The presence of anthropogenic radionuclides (236U, 239Pu,240Pu, 241Am, and 237Np) in the penetrators indicates that at least part of the uranium originated from the reprocessing of nuclear fuel. Because the concentrations of radionuclides are very low, their radiotoxicological effect is negligible. (orig.)

  10. Determination of {sup 238}Pu, {sup 239+240}Pu, {sup 241}Pu and {sup 241}Am in radioactive waste from IPEN reactor

    Energy Technology Data Exchange (ETDEWEB)

    Geraldo, Bianca; Taddei, Maria Helena T.; Cheberle, Sandra M.; Ferreira, Marcelo T., E-mail: bgeraldo@cnen.gov.b, E-mail: mhtaddei@cnen.gov.b, E-mail: scsantos@cnen.gov.b, E-mail: ferreira@cnen.gov.b [Brazilian Nuclear Energy Commission (LAPOC/CNEN-MG), Pocos de Caldas, MG (Brazil). Lab. of Pocos de Caldas; Marumo, Julio T., E-mail: jtmarumo@ipen.b [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2011-07-01

    Ion exchange resin is a common type of radioactive waste arising from treatment of coolant water of the main circuit of research and nuclear power reactors. This waste contains high concentrations of fission and activation products. The management of this waste includes its characterization in order to determine and quantify specific radionuclides including those known as difficult-to-measure radionuclides (RDM). The analysis of RDMs generally involves expensive and time-consuming complex radiochemical analysis for purification and separation of the radionuclides. The objective of this work is to show an easy methodology for quantifying plutonium and americium isotopes in spent ion exchange resin, used for purification of the cooling water of the IEA-R1 reactor located at the Nuclear and Energy Research Institute, IPEN-CNEN/SP. The resins were destroyed by acid digestion, followed by purification and separation of the Pu and Am isotopes with anionic and chromatographic resins. {sup 238}Pu, {sup 239}+{sup 24}'0Pu, and {sup 24}'1Am isotopes were analyzed in an alpha spectrometer equipped with surface barrier detectors. {sup 241}Pu isotope was analyzed by liquid scintillation counting. Chemical recovery yield ranged from 73 to 98% for Pu and 77 to 98% for Am, demonstrating that the methodology is suitable for identification and quantification of the isotopes studied in spent resins. (author)

  11. Evidence for Hydroxamate Siderophores and Other N-Containing Organic Compounds Controlling (239,240)Pu Immobilization and Remobilization in a Wetland Sediment.

    Science.gov (United States)

    Xu, Chen; Zhang, Saijin; Kaplan, Daniel I; Ho, Yi-Fang; Schwehr, Kathleen A; Roberts, Kimberly A; Chen, Hongmei; DiDonato, Nicole; Athon, Matthew; Hatcher, Patrick G; Santschi, Peter H

    2015-10-01

    Pu concentrations in wetland surface sediments collected downstream of a former nuclear processing facility in F-Area of the Savannah River Site (SRS), USA, were ∼2.5 times greater than those measured in the associated upland aquifer sediments; similarly, the Pu concentration solid/water ratios were orders of magnitude greater in the wetland than in the low-organic matter content aquifer soils. Sediment Pu concentrations were correlated to total organic carbon and total nitrogen contents and even more strongly to hydroxamate siderophore (HS) concentrations. The HS were detected in the particulate or colloidal phases of the sediments but not in the low molecular weight fractions (water extract") via an isoelectric focusing experiment (IEF). An electrospray ionization Fourier-transform ion cyclotron resonance ultrahigh resolution mass spectrometry (ESI FTICR-MS) spectral comparison of the IEF extract and a siderophore standard (desferrioxamine; DFO) suggested the presence of HS functionalities in the IEF extract. This study suggests that while HS are a very minor component in the sediment particulate/colloidal fractions, their concentrations greatly exceed those of ambient Pu, and HS may play an especially important role in Pu immobilization/remobilization in wetland sediments. PMID:26313339

  12. Artificial radioactivity and marine environment. Study of 238Pu, 239Pu+240Pu, 241Pu and 241Am in the Mediterranean sea

    International Nuclear Information System (INIS)

    This paper is in two parts. Part one is about the methods for analyzing transuranium elements particularly the development of an analytical process for plutonium and for perfecting an Americium analyzing method, capable of treating samples of 200 litres of sea water, 100 grams of sediment and 100 grams of biological matter. Part two concerns the in situ determinations carried out within the scope of the study on the distribution and behaviour of transuranium elements in the Mediterranean sea. The high sea studies concerned the effects of atmospheric fall out and the vertical distribution of Pu and Am. Studies along the coasts enabled a quantitative study to be made of the contribution of rivers to the Mediterranean and to study the distribution of Pu along the French Mediterranean coast line

  13. PLANTS AS BIO-MONITORS FOR 137CS, 238PU, 239, 240PU AND 40K AT THE SAVANNAH RIVER SITE

    Energy Technology Data Exchange (ETDEWEB)

    Caldwell, E.; Duff, M.; Ferguson, C.

    2010-12-16

    The nuclear fuel cycle generates a considerable amount of radioactive waste, which often includes nuclear fission products, such as strontium-90 ({sup 90}Sr) and cesium-137 ({sup 137}Cs), and actinides such as uranium (U) and plutonium (Pu). When released into the environment, large quantities of these radionuclides can present considerable problems to man and biota due to their radioactive nature and, in some cases as with the actinides, their chemical toxicity. Radionuclides are expected to decay at a known rate. Yet, research has shown the rate of elimination from an ecosystem to differ from the decay rate due to physical, chemical and biological processes that remove the contaminant or reduce its biological availability. Knowledge regarding the rate by which a contaminant is eliminated from an ecosystem (ecological half-life) is important for evaluating the duration and potential severity of risk. To better understand a contaminants impact on an environment, consideration should be given to plants. As primary producers, they represent an important mode of contamination transfer from sediments and soils into the food chain. Contaminants that are chemically and/or physically sequestered in a media are less likely to be bio-available to plants and therefore an ecosystem.

  14. The effect of permafrost on soil erosion using meteoric 10Be, 137Cs and 239+240Pu in the Eastern Swiss Alps

    Science.gov (United States)

    Pichler, Barbara; Brandovà, Dagmar; Alewell, Christine; Ivy-Ochs, Susan; Kubik, Peter W.; Kneisel, Christof; Meusburger, Katrin; Ketterer, Michael; Egli, Markus

    2013-04-01

    Permafrost ecosystems are highly sensitive to climate warming. The expected changes in the thermal and hydrological soil regime might have crucial consequences on soil erosion processes. Therefore, the determination of erosional activities on the long- (since the beginning of soil formation) and mid-term (last 50-60 yr) using cosmogenic and anthropogenic radionuclides can provide important information on past and ongoing processes. Permafrost soils in the Alps and their behaviour with climate change are only rarely studied. The expected new insights will lead to a better understanding of the processes of high mountain soils and are a further step towards improving climate-related modelling of fast warming scenarios and increasing system disequilibria. Our aim is to quantify soil erosion processes in permafrost soils and nearby unfrozen soils in the Alpine (sites at 2700 m asl) and the sub-Alpine (sites 1800 m asl) range of the Swiss Alps (Upper Engadine). We hypothesise that permafrost soils differ distinctly in their long- and mid-term soil erosion rates due to different water retention capacities. Long-term soil erosion was assessed using meteoric 10Be. Meteoric 10Be in a soil profile was estimated assuming that it is has been deposited as a function of precipitation and adsorbed in the fine earth fraction (

  15. Combined procedure using radiochemical separation of plutonium, americium and uranium radionuclides for alpha-spectrometry

    International Nuclear Information System (INIS)

    Radiochemical separation of Pu, Am and U was tested from synthetic solutions and evaporator concentrate samples from nuclear power plants for isolation of each of them for alpha-spectrometry analysis. The separation was performed by anion-exchange chromatography, extraction chromatography, using TRU resin, and precipitation techniques. The aim of the study was to develop a sensitive analytical procedure for the sequential determination of 242Pu, 238Pu, 239+240Pu, 241Am and 235,238U in radioactive wastes. 238Pu, 242Pu, 243Am and 232U were used as tracers. The measurements of α emitting radionuclides were performed by semiconductor detector that is used especially when spectrometric information is needed. For synthetic solutions the chemical recovery was based on associated iron concentration and was about 93%. (author)

  16. {sup 90}Sr, {sup 238}U, {sup 234}U, {sup 137}Cs, {sup 40}K and {sup 239/240}Pu in Emmental type cheese produced in different regions of Western Europe

    Energy Technology Data Exchange (ETDEWEB)

    Froidevaux, P. E-mail: pascal.froidevaux@inst.hospvd.ch; Geering, J.-J.; Pillonel, L.; Bosset, J.-O.; Valley, J.-F

    2004-07-01

    A method is presented for the determination of {sup 90}Sr and uranium in Emmental type cheese collected in dairy plants from different European countries. Results display a significant correlation (r=0.708, Student t-test=6.02) between the {sup 90}Sr content of the cheese and the altitude of grazing. The highest {sup 90}Sr activity is 1.13 Bq kg{sup -1} of cheese and the lowest is 0.29 Bq kg{sup -1}. Uranium activity is very low with a highest {sup 238}U value of 27 mBq kg{sup -1}. In addition, {sup 234}U/{sup 238}U ratio shows a large enrichment in {sup 234}U for every location. Without any significant indication of the geographic origin of the cheese, this enrichment is believed to be due to the geological features of the pasture, soil and underground water. These results tend to prove that the contamination of milk by uranium originates principally from the water that the cows drink instead of the forage. This finding may have a great importance in models dealing with dairy food contamination by radionuclides following a nuclear accident. Also, the {sup 90}Sr content and to a lesser extent the {sup 234}U/{sup 238}U ratio could be used to trace the authenticity of the origin of the cheese. {sup 137}Cs activity is lower than the detection limit of 0.1 Bq kg{sup -1} in all the samples collected (n=20). Based on natural {sup 40}K activity in cheese (15-21 Bq kg{sup -1}), the decontamination factor for the alkaline cations from milk to cheese is about 20. Plutonium activity stays below the detection limit of 0.3 mBq kg{sup -1}.

  17. A method of measurement of (239)Pu, (240)Pu, (241)Pu in high U content marine sediments by sector field ICP-MS and its application to Fukushima sediment samples.

    Science.gov (United States)

    Bu, Wenting; Zheng, Jian; Guo, Qiuju; Aono, Tatsuo; Tazoe, Hirofumi; Tagami, Keiko; Uchida, Shigeo; Yamada, Masatoshi

    2014-01-01

    An accurate and precise analytical method is highly needed for the determination of Pu isotopes in marine sediments for the long-term marine environment monitoring that is being done since the Fukushima Dai-ichi Nuclear Power Plant accident. The elimination of uranium from the sediment samples needs to be carefully checked. We established an analytical method based on anion-exchange chromatography and SF-ICP-MS in this work. A uranium decontamination factor of 2 × 10(6) was achieved, and the U concentrations in the final sample solutions were typically below 4 pg mL(-1), thus no extra correction of (238)U interferences from the Pu spectra was needed. The method was suitable for the analysis of (241)Pu in marine sediments using large sample amounts (>10 g). We validated the method by measuring marine sediment reference materials and our results agreed well with the certified and the literature values. Surface sediments and one sediment core sample collected after the nuclear accident were analyzed. The characterization of (241)Pu/(239)Pu atom ratios in the surface sediments and the vertical distribution of Pu isotopes showed that there was no detectable Pu contamination from the nuclear accident in the marine sediments collected 30 km off the plant site.

  18. Procedures for determination of 239,240Pu, 241Am, 237Np, 234,238U, 228,230,232Th, 99Tc and 210Pb-210Po in environmental material

    International Nuclear Information System (INIS)

    Since 1987, the Department of Nuclear Safety Research, Risoe National Laboratory has developed procedures for analysis of low-level amounts of radioactivity in large samples of 200 liters seawater, 10 gram sediment, soil and other environmental materials. These analytical procedures provide high chemical yields, good resolution and excellent decontamination factors for large environmental samples analysed by alpha spectrometry and mass spectrometry (ICPMS). The procedures have been checked through practical analysis work and are used in Norway, the Netherlands, Germany, Spain, France and Denmark. (au)

  19. Fast neutron capture in actinide isotopes: recent results from Karlsruhe

    International Nuclear Information System (INIS)

    Capture gamma-ray spectra of 241Am, 240Pu, 242Pu 238U and 197Au were calculated in the framework of the spherical optical model and the statistical model. These spectra were used to correct experimental data for the capture cross sections of 240242Pu and 241Am from relative measurements using a Moxon Rae-detector with graphite converter and 197Au as well as 238U as standards. This correction is required to take into account that the detector efficiency is not exactly proportional to gamma-ray energy. The resulting correction factors proved to be negligible for measurements relative to 238U, whereas they are approx. 3% if gold is used as a standard. The capture cross section of 243Am has been measured in the energy range 10 to 250 keV using kinematically collimated neutrons from the 7Li(p,n) and T(p,n) reaction. The samples are positioned at flight paths of 5 to 7 cm and gold was used as a standard. Capture events were detected by two Moxon-Rae detectors with graphite and bismuth-graphite converters shielded by 0.5 to 2 cm of lead. Fission events were detected by a NE213 liquid scintillator. The present status of the experiment and some preliminary results will be presented

  20. Sequential isotopic determination of plutonium, thorium, americium and uranium in the air filter and drinking water samples around the WIPP site

    International Nuclear Information System (INIS)

    The simultaneous determination of actinides in air filter and water samples around the WIPP site have been demonstrated. The analytical method is based on the selective separation and purification by anion exchange and Eichrome-TEVA, TRU and DGA-resin followed by determination of actinides by alpha spectrometry. Counting sources for alpha spectrometric measurements were prepared by microcoprecipitation on neodymium fluoride (NdF3). Radiochemical yields were determined using 242Pu, 229Th, 243Am and 232U as tracers. The validation of the method is performed through the analysis of reference materials or participating in laboratory intercomparison programs. The plutonium concentrations in aerosols varied seasonally, being highest in spring and summer due to the spring-time enhanced wind-storm transportation of radioactive aerosols from the stratosphere to the troposphere. The 238Pu/239+240Pu activity ratio in the aerosol samples is typically close to that of global fallout from historic above-ground nuclear weapons testing. The results presented here indicate that the source of plutonium in the WIPP environment results mainly from global nuclear fallout and there is no evidence of increases in radiological contaminants in the region that could be attributed to releases from the WIPP. (author)

  1. ANSI/ANS-8.15-1981(R87): Nuclear criticality control of special actinide elements

    International Nuclear Information System (INIS)

    The American National Standard, open-quotes Nuclear Criticality Safety in Operations with Fissionable Materials Outside Reactotorsclose quotes American National Standards Institute/American Nuclear Society (ANSI/ANS)-8.1-1983(R88) provides guidance for the nuclides 233U, 235U, and 239Pu. These three nuclides are of primary interest in out-of-reactor criticality safety since they are the most commonly encountered in the vast majority of operations. However, some operations can involve nuclides other than 233U, 235U, and 239Pu in sufficient quantities that their effect on criticality safety could be of concern. ANSI/ANS-8.15-1981(R87) open-quotes Nuclear Criticality Control of Special Actinide Elements,close quotes provides guidance for 15 such nuclides. The standard was approved for use on November 9, 1981. When it received its first 5-yr review, no changes were made, and it was reaffirmed effective October 30, 1987. The standard was again reviewed and reaffirmed without changes in December 1995. The next 5-yr review of the standard is due in December 2000. The affected nuclides are 237Np, 238Pu, 240Pu, 242Pu, 241Am, 243Am, 244Cm, 239Pu, 241Pu, 242mAm, 243Cm, 245Cm, 247Cm, 249Cf, and 251Cf

  2. Behavior of actinides in the Integral Fast Reactor fuel cycle

    Energy Technology Data Exchange (ETDEWEB)

    Courtney, J.C. [Louisiana State Univ., Baton Rouge, LA (United States). Nuclear Science Center; Lineberry, M.J. [Argonne National Lab., Idaho Falls, ID (United States). Technology Development Div.

    1994-06-01

    The Integral Fast Reactor (IFR) under development by Argonne National Laboratory uses metallic fuels instead of ceramics. This allows electrorefining of spent fuels and presents opportunities for recycling minor actinide elements. Four minor actinides ({sup 237}Np, {sup 240}Pu, {sup 241}Am, and {sup 243}Am) determine the waste storage requirements of spent fuel from all types of fission reactors. These nuclides behave the same as uranium and other plutonium isotopes in electrorefining, so they can be recycled back to the reactor without elaborate chemical processing. An experiment has been designed to demonstrate the effectiveness of the high-energy neutron spectra of the IFR in consuming these four nuclides and plutonium. Eighteen sets of seven actinide and five light metal targets have been selected for ten day exposure in the Experimental Breeder Reactor-2 which serves as a prototype of the IFR. Post-irradiation analyses of the exposed targets by gamma, alpha, and mass spectroscopy are used to determine nuclear reaction-rates and neutron spectra. These experimental data increase the authors` confidence in their ability to predict reaction rates in candidate IFR designs using a variety of neutron transport and diffusion programs.

  3. Characterization of actinide physics specimens for the US/UK joint experiment in the Dounreay Prototype Fast Reactor

    International Nuclear Information System (INIS)

    The United States and the United Kingdom are engaged in a joint research program in which samples of the higher actinides are irradiated in the Dounreay Prototype Fast Reactor in Scotland. The purpose of the porogram is (1) to study the materials behavior of selected higher actinide fuels and (2) to determine the integral cross sections of a wide variety of the higher actinide isotopes. Samples of the actinides are incorporated in fuel pins inserted in the core. For the fuel study, the actinides selected are 241Am and 244Cm in the form of Am2O3, Cm2O3, and Am6Cm(RE)7O21, where (RE) represents a mixture of lanthanides. For the cross-section determinations, the samples are milligram quantities of actinide oxides of 248Cm, 246Cm, 244Cm, 243Cm, 243Am, 241Am, 244Pu, 242Pu, 241Pu, 240Pu, 239Pu, 238Pu, 237Np, 238U, 236U, 235U, 234U, 233U, 232Th, 230Th, and 231Pa encapsulated in vanadium. Coincident with the irradiations, neutron flux and energy spectral measurements are made with vanadium-encapsulated dosimeter materials located within the same fuel pins

  4. Preparation of actinide specimens for the US/UK joint experiment in the Dounreay Prototype Fast Reactor

    International Nuclear Information System (INIS)

    A joint research program involving the United States and the United Kingdom was initiated about four years ago for the purpose of studying the fuel behavior of higher actinides using in-core irradiation in the fast reactor at Dounreay, Scotland. Simultaneously, determination of integral cross sections of a wide variety of higher actinide isotopes (physics specimens) was proposed. Coincidental neutron flux and energy spectral measurements were to be made using vanadium encapsulated dosimetry materials in the immediate region of the fuel pellets and physics samples. The higher actinide samples chosen for the fuel study were 241Am and 244Cm in the forms of Am2O3, Cm2O3, and Am6Cm(RE)7O21, where (RE) represents a mixture of lanthanides. Milligram quantities of actinide oxides of 248Cm, 246Cm, 244Cm, 243Cm, 243Am, 241Am, 244Pu, 242Pu, 241Pu, 240Pu, 239Pu, 238Pu, 237Np, 238U, 236U, 235U, 234U, 233U, 232Th, 230Th, and 231Pa were encapsulated to obtain nuclear cross section and reaction rate data for these materials

  5. Artificial radionuclides in the atmosphere over Lithuania

    International Nuclear Information System (INIS)

    Systematic observations of radionuclide composition and concentration in the atmosphere have been carried out at the Institute of Physics in Vilnius since 1963. An increase in activity concentration of radionuclides in the atmosphere was observed after nuclear weapon tests and the Chernobyl NPP accident. At present the radiation situation in Lithuania is determined by two main sources of radionuclides, forest fire and resuspension products transferred from highly polluted region of the Ukraine and Belarus. During forest fires the increase in activity concentration of 137Cs in the atmosphere was registered in many countries and in Lithuania as well. This work summarizes the experimental data on transport of cesium, plutonium, americium from the highly contaminated territories after the Chernobyl accident. The activity concentrations of 137Cs were measured in two - three days samples while plutonium and americium in monthly samples. In addition, the analyses of the events of the increase activity concentration, meteorological situation, speciation of radionuclides and mechanisms of formation and transformation of aerosol carriers of radionuclides are presented. Aerosols were sampled on perchlorvinyl filters and the large volume air samplers with a flow rate from 2400 m3/h to about 6000 m3/h were used. The radiochemical analyses of monthly samples of aerosol ashes (about 30 g) were performed. For separation of Pu isotopes the TOPO/cyclohexane extraction and radiochemical purification using UTEVA resin were performed, Am was separated after TOPO/cyclohexane extraction using TRU and TEVA resins (100-150 μm). 242Pu and 243Am were used as tracers in the separation procedure. The alpha spectrometry measurements of Pu and Am isotopes deposited on a stainless steel disc were carried out with the Alphaquattro (Silena) spectrometer. 137Cs was determined by gamma-ray spectrometry using the high purity HPGe detector (resolution - 1.9 keV/1.33 Mev, efficiency - 42%). Accuracy

  6. Distribution of the Pu and Am isotopes in the BOMARC missile site soil

    International Nuclear Information System (INIS)

    Full text: The activity concentrations as well as the activity and atomic ratios of the Pu and Am isotopes in different sizes of the soil sampled around BOMARC Missile Site were obtained by radiochemical analysis. The association pattern between the actinides and soil particles was investigated using a spherical model of a particle size with a variable radius. From the activity and atomic ratios of Pu and Am, the origin of the Pu and Am isotopes was identified in the BOMARC Missile Site soil. Plutonium is one of the transuranic elements which is primarily present in the environment as a result of human activity, namely as the fallout from nuclear weapon testings during the late 1940s through to the early 1960s, and accidental releases due to military mishaps. One particular mishap occurred in 1960 at McGuire Air Force Base in New Jersey, when a Boeing Michigan Aeronautical Research Center (BOMARC) missile caught fire and the warhead was partially melted by the fire. Although the missile did not explode, subsequent fire fighting activities contributed to the dispersion of weapons grade plutonium into the local environment. Soil samples around BOMARC site were taken to a depth of 2 inches by the U.S. Air Force Institute for Environment. The soil samples were blended and homogenized in a soil tumbler, and subdivided into approximately 20-gram samples. Grain size fractions were determined with sieves. Determination of 239,240Pu, 238Pu, 241Pu, 241Am and 239U was performed using a radiochemical method. After adding 242Pu, 243Am and 232U tracers, a total of a 2 g ashed soil sample was dissolved with concentrated HNO3 and HF and evaporated to dryness. Dissolution in HNO3/HF was repeated and again evaporated to dryness. The residue was dissolved in 9 M HCl. After filtration, the solution was passed over an anion exchange column (chloride form) to which the Pu was sorbed. The columns were washed with 9 M HCl followed by 8 M HNO3. This effluent was evaporated to dryness and

  7. Distribution of Pu and Am isotopes in BOMARC missile site soil

    International Nuclear Information System (INIS)

    Full text: The activity concentrations as well as the activity and atomic ratios of the Pu and Am isotopes in different sizes of the soil sampled around BOMARC Missile Site were obtained by radiochemical analysis. The association pattern between the actinides and soil particles was investigated using a spherical model of a particle size with a variable radius. From the activity and atomic ratios of Pu and Am, the origin of the Pu and Am isotopes was identified in the BOMARC Missile Site soil. Plutonium is one of the transuranic elements which is primarily present in the environment as a result of human activity, namely as the fallout from nuclear weapon testings during the late 1940s through to the early 1960s, and accidental releases due to military mishaps. One particular mishap occurred in 1960 at McGuire Air Force Base in New Jersey, when a Boeing Michigan Aeronautical Research Center (BOMARC) missile caught fire and the warhead was partially melted by the fire. Although the missile did not explode, subsequent fire fighting activities contributed to the dispersion of weapons grade plutonium into the local environment. Soil samples around BOMARC site were taken to a depth of 2 inches by the U.S. Air Force Institute for Environment. The soil samples were blended and homogenized in a soil tumbler, and subdivided into approximately 20-gram samples. Grain size fractions were determined with sieves. Determination of 239,240Pu, 238Pu, 241Pu, 241Am and 238U was performed using a radiochemical method. After adding 242Pu, 243Am and 232U tracers, a total of a 2 g ashed soil sample was dissolved with concentrated HNO3 and HF and evaporated to dryness. Dissolution in HNO3/HF was repeated and again evaporated to dryness. The residue was dissolved in 9 M HCl. After filtration, the solution was passed over an anion exchange column (chloride form) to which the Pu was sorbed. The columns were washed with 9 M HCl followed by 8 M HNO3. This effluent was evaporated to dryness and

  8. OSMOSE program : statistical review of oscillation measurements in the MINERVE reactor R1-UO2 configuration.

    Energy Technology Data Exchange (ETDEWEB)

    Stoven, G.; Klann, R.; Zhong, Z.; Nuclear Engineering Division

    2007-08-28

    The OSMOSE program is a collaboration on reactor physics experiments between the United States Department of Energy and the France Commissariat Energie Atomique. At the working level, it is a collaborative effort between the Argonne National Laboratory and the CEA Cadarache Research Center. The objective of this program is to measure very accurate integral reaction rates in representative spectra for the actinides important to future nuclear system designs, and to provide the experimental data for improving the basic nuclear data files. The main outcome of the OSMOSE measurement program will be an experimental database of reactivity-worth measurements in different neutron spectra for the heavy nuclides. This database can then be used as a benchmark to verify and validate reactor analysis codes. The OSMOSE program (Oscillation in Minerve of isotopes in Eupraxic Spectra) aims at improving neutronic predictions of advanced nuclear fuels through oscillation measurements in the MINERVE facility on samples containing the following separated actinides: {sup 232}Th, {sup 233}U, {sup 234}U, {sup 235}U, {sup 236}U, {sup 238}U, {sup 237}Np, {sup 238}Pu, {sup 239}Pu, {sup 240}Pu, {sup 241}Pu, {sup 242}Pu, {sup 241}Am, {sup 243}Am, {sup 244}Cm, and {sup 245}Cm. The first part of this report provides an overview of the experimental protocol and the typical processing of a series of experimental results which is currently performed at CEA-Cadarache. In the second part of the report, improvements to this technique are presented, as well as the program that was created to process oscillation measurement results from the MINERVE facility in the future.

  9. Highly enriched isotope samples of uranium and transuranium elements for scientific investigation

    Science.gov (United States)

    Vesnovskii, Stanislav P.; Polynov, Vladimir N.; Danilin, Lev. D.

    1992-02-01

    The paper describes the production of highly enriched isotopes of uranium, plutonium, americium and curium by electromagnetic separation for scientific and applied researches in physics, chemistry, geology, medicine, biology and other fields. Using the equipment described, the isotopes are produced in quantities sufficient to set up nuclear physical experiments, to produce nuclear reference materials and standard sources for calibration of radiometrical and mass spectrometrical equipment, in radionuclide metrology, etc. For the following isotopes the indicated degrees of isotopic enrichment were achieved: 233U - 99.97%; 235U - 99.97%; 236U - 98.0%; 238U - 99.997%; 238Pu - 99.6%; 239Pu - 99.9977%; 240Pu - 99.9-100%; 241Pu - 96.998%; 242Pu - 97.8-99.96%; 244Pu - 96.7%; 241Am - 99.6%; 242Am - 73.6%; 243Am - 99.2-99.94%; 243Cm - 99.99%; 245Cm - 99.998%; 246Cm - 99.8%; 247Cm - 90%; 248Cm - 97%. Methods for preparing layers of highly enriched isotopes on various substances are presented: - electrochemical deposition of transuranic elements from aqueous-organic and organic media and vacuum spraying: - the method of foil and coating formation via compounds in the vapour phase; - the method of fabrication of layers of transuranic elements on superthin (1-2 μm) metal substrates with additional isolating polymer-metal coatings (0.2-0.4 μm), that substantially decrease material transfer from the active layer and increase safety of product handling.

  10. Fabrication and characterization of MCC approved testing material: ATM-9 glass

    International Nuclear Information System (INIS)

    The Materials Characterization Center ATM-9 glass is designed to be representative of glass to be produced by the Defense Waste Processing Facility at the Savannah River Plant, Aiken, South Carolina. ATM-9 glass contains all of the major components of the DWPF glass and corresponds to a waste loading of 29 wt %. The feedstock material for this glass was supplied by Savannah River Laboratory, Aiken, SC, as SRL-165 Black Frit to which was added Ba, Cs, Md, Nd, Zr, as well as 99Tc, depleted U, 237Np, 239+240Pu, and 243Am. The glass was produced under reducing conditions by the addition of 0.7 wt % graphite during the final melting process. Three kilograms of the glass were produced from April to May of 1984. On final melting, the glass was formed into stress-annealed rectangular bars of two sizes: 1.9 x 1.9 x 10 cm and 1.3 x 1.3 x 10 cm. Seventeen bars of each size were made. The analyzed composition of ATM-9 glass is listed. Examination by optical microscopy of a single transverse section from one bar showed random porosity estimated at 0.36 vol % with nominal pore diameters ranging from approx. 5 μm to 200 μm. Only one distinct second phase was observed and it was at a low concentraction level in the glass matrix. The phase appeared as spherical metallic particles. X-ray diffraction analysis of this same sample did not show any diffraction peaks from crystalline components, indicating that the glass contained less than 5 wt % of crystalline devitrification products. The even shading on the radiograph exposure indicated a generally uniform distribution of radioactivity throughout the glass matrix, with no distinct high-concentration regions

  11. Safe handling of kilogram amounts of fuel-grade plutonium and of gram amounts of plutonium-238, americium-241 and curium-244

    International Nuclear Information System (INIS)

    During the past 10 years about 600 glove-boxes have been installed at the Institute for Transuranium Elements at Karlsruhe. About 80% of these glove-boxes have been designed and equipped for handling 100-g to 1-kg amounts of 239Pu containing 8-12% 240Pu (low-exposure plutonium). A small proportion of the glove-boxes is equipped with additional shielding in the form of lead sheet or lead glass for work with recycled plutonium. In these glove-boxes gram-amounts of 241Am have also been handled for preparation of Al-Am targets using tongs and additional shielding inside the glove-boxes themselves. Water- and lead-shielded glove-boxes equipped with telemanipulators have been installed for routine work with gram-amounts of 241Am, 243Am and 244Cm. A prediction of the expected radiation dose for the personnel is difficult and only valid for a preparation procedure with well-defined preparation steps, owing to the fact that gamma dose-rates depend strongly upon proximity and source seize. Gamma radiation dose measurements during non-routine work for 241Am target preparation showed that handling of gram amounts leads to a rather high irradiation dose for the personnel, despite lead or steel glove-box shielding and shielding within the glove-boxes. A direct glove-hand to americium contact must be avoided. For all glove-handling of materials with gamma radiation an irradiation control of the forearms of the personnel by, for example, thermoluminescence dosimeters is necessary. Routine handling of americium and curium should be executed with master-slave equipment behind neutron and gamma shielding. (author)

  12. New radiochemical methods for determination of 237Np a 241Pu using extraction chromatography (Presentation)

    International Nuclear Information System (INIS)

    Thesis was focused on the development of a new methodology for the separation of anthropogenic transuranium radionuclides 237Np a 241Pu from different kinds of matrices. The analytical methods used in this study were based on extraction chromatography and were optimized according to the sample type. The proposed radiochemical procedure is a combination of two algorithms, which represent the separation of radionuclides by using extraction chromatographic sorbents TEVA resin and TRU resin supplied by Eichrom Technologies LLC. 239Np a 237Np were selectively captured on sorbent TEVA resin in oxidation state 4+. TRU resin was used for purification of plutonium fraction from interfering americium radionuclide. 242Pu and 239Np radionuclides as tracers have been used to monitor the radiochemical yields of separation. Before every radiochemical separation tracer radionuclide 239Np was obtained by separation from the parent radionuclide 243Am, which is in radioactive equilibrium to 239Np. The average yield of chemical separation was 69,3% for 239Np at 277 keV energy line and 65,9% at 228 keV energy line. The NPL AH-B08069 (2008) samples which consist of the mixture of alpha-radionuclides were used for the modification and optimization of separation method used for separation of Np and Pu in model samples. This method provided high radiochemical yields of 239,240Pu (95,0 ± 3,5)% and 237Np (87,9 ± 3,0)%.. Reliability of the method was verified by applying our modified separation procedures on reference materials IAEA-375 and IAEA-414 supplied by International Atomic Energy Agency. A good agreement between the results is obtained by this procedure and the certified values were found. Samples of contaminated soils from the area of Nuclear power plant A-1 Jaslovske Bohunice which is stored temporarily before disposal were analyzed using developed separation procedure. Specific activity of investigated radionuclides was determined in these samples. (author)

  13. New radiochemical methods for determination of 237Np a 241Pu using extraction chromatography

    International Nuclear Information System (INIS)

    Thesis was focused on the development of a new methodology for the separation of anthropogenic transuranium radionuclides 237Np a 241Pu from different kinds of matrices. The analytical methods used in this study were based on extraction chromatography and were optimized according to the sample type. The proposed radiochemical procedure is a combination of two algorithms, which represent the separation of radionuclides by using extraction chromatographic sorbents TEVA resin and TRU resin supplied by Eichrom Technologies LLC. 239Np a 237Np were selectively captured on sorbent TEVA resin in oxidation state 4+. TRU resin was used for purification of plutonium fraction from interfering americium radionuclide. 242Pu and 239Np radionuclides as tracers have been used to monitor the radiochemical yields of separation. Before every radiochemical separation tracer radionuclide 239Np was obtained by separation from the parent radionuclide 243Am, which is in radioactive equilibrium to 239Np. The average yield of chemical separation was 69,3% for 239Np at 277 keV energy line and 65,9% at 228 keV energy line. The NPL AH-B08069 (2008) samples which consist of the mixture of alpha-radionuclides were used for the modification and optimization of separation method used for separation of Np and Pu in model samples. This method provided high radiochemical yields of 239,240Pu (95,0 ± 3,5)% and 237Np (87,9 ± 3,0)%.. Reliability of the method was verified by applying our modified separation procedures on reference materials IAEA-375 and IAEA-414 supplied by International Atomic Energy Agency. A good agreement between the results is obtained by this procedure and the certified values were found. Samples of contaminated soils from the area of Nuclear power plant A-1 Jaslovske Bohunice which is stored temporarily before disposal were analyzed using developed separation procedure. Specific activity of investigated radionuclides was determined in these samples. (author)

  14. Simultaneous photon and neutron interrogation using an electron accelerator in order to quantify actinides in encapsulated radioactive wastes

    International Nuclear Information System (INIS)

    Measuring out alpha emitters, such as (234,235,236,238U 238,239,240,242,244Pu, 237Np 241,243Am...), in solid radioactive waste, allows us to quantify the alpha activity in a drum and then to classify it. The SIMPHONIE (SIMultaneous PHOton and Neutron Interrogation Experiment) method, developed in this Ph.D. work, combines both the Active Neutron Interrogation and the Induced Photofission Interrogation techniques simultaneously. Its purpose is to quantify in only one measurement, fissile (235U, 239,241Pu...) and fertile (236,238U, 238,240Pu...) elements separately. In the first chapter of this Ph.D. report, we present the principle of the Radioactive Waste Management in France. The second chapter deals with the physical properties of neutron fission and of photofission. These two nuclear reactions are the basis of the SIMPHONIE method. Moreover, one of our purposes was to develop the ELEPHANT (ELEctron PHoton And Neutron Transport) code in view to simulate the electron, photon and neutron transport, including the (γ, n), (γ, 2n) and (γ, f) photonuclear reactions that are not taken into account in the MCNP4 (Monte Carlo N-Particle) code. The simulation codes developed and used in this work are detailed in the third chapter. Finally, the fourth chapter gives the experimental results of SIMPHONIE obtained by using the DGA/ETCA electron linear accelerators located at Arcueil, France. Fissile (235U, 239Pu) and fertile (238U) samples were studied. Furthermore, comparisons between experimental results and calculated data of photoneutron production in tungsten, copper, praseodymium and beryllium by using an electron LINear Accelerator (LINAC) are given. This allows us to evaluate the validity degree of the ELEPHANT code, and finally the feasibility of the SIMPHONIE method. (author)

  15. Simultaneous photon and neutron interrogation using an electron accelerator in order to quantify actinides in encapsulated radioactive wastes; Double interrogation simultanee neutrons et photons utilisant un accelerateur d'electrons pour la caracterisation separee des actinides dans les dechets radioactifs enrobes

    Energy Technology Data Exchange (ETDEWEB)

    Jallu, F

    1999-09-24

    Measuring out alpha emitters, such as ({sup 234,235,236,238}U {sup 238,239,240,242,}2{sup 44P}u, {sup 237}Np {sup 241,243}Am...), in solid radioactive waste, allows us to quantify the alpha activity in a drum and then to classify it. The SIMPHONIE (SIMultaneous PHOton and Neutron Interrogation Experiment) method, developed in this Ph.D. work, combines both the Active Neutron Interrogation and the Induced Photofission Interrogation techniques simultaneously. Its purpose is to quantify in only one measurement, fissile ({sup 235}U, {sup 239,241}Pu...) and fertile ({sup 236,238}U, {sup 238,240}Pu...) elements separately. In the first chapter of this Ph.D. report, we present the principle of the Radioactive Waste Management in France. The second chapter deals with the physical properties of neutron fission and of photofission. These two nuclear reactions are the basis of the SIMPHONIE method. Moreover, one of our purposes was to develop the ELEPHANT (ELEctron PHoton And Neutron Transport) code in view to simulate the electron, photon and neutron transport, including the ({gamma}, n), ({gamma}, 2n) and ({gamma}, f) photonuclear reactions that are not taken into account in the MCNP4 (Monte Carlo N-Particle) code. The simulation codes developed and used in this work are detailed in the third chapter. Finally, the fourth chapter gives the experimental results of SIMPHONIE obtained by using the DGA/ETCA electron linear accelerators located at Arcueil, France. Fissile ({sup 235}U, {sup 239}Pu) and fertile ({sup 238}U) samples were studied. Furthermore, comparisons between experimental results and calculated data of photoneutron production in tungsten, copper, praseodymium and beryllium by using an electron LINear Accelerator (LINAC) are given. This allows us to evaluate the validity degree of the ELEPHANT code, and finally the feasibility of the SIMPHONIE method. (author)

  16. PRELIMINARY CROSS SECTION AND NU-BAR COVARIANCES FOR WPEC SUBGROUP 26

    Energy Technology Data Exchange (ETDEWEB)

    ROCHMAN,D.

    2007-01-31

    We report preliminary cross section covariances developed for the WPEC Subgroup 26 for 45 out of 52 requested materials. The covariances were produced in 15- and 187-group representations as follows: (1) 36 isotopes ({sup 16}O, {sup 19}F, {sup 23}Na, {sup 27}Al, {sup 28}Si, {sup 52}Cr, {sup 56,56}Fe, {sup 58}Ni, {sup 90,91,92,94}Zr, {sup 166,167,168,170}Er, {sup 206,207,208}Pb, {sup 209}Bi, {sup 233,234,236}U, {sup 237}Np, {sup 238,240,241,242}Pu, {sup 241,242m,243}Am, {sup 242,243,244,245}Cm) were evaluated using the BNL-LANL methodology. For the thermal region and the resolved and unresolved resonance regions, the methodology has been based on the Atlas-Kalman approach, in the fast neutron region the Empire-Kalman method has been used; (2) 6 isotopes ({sup 155,156,157,158,160}Gd and {sup 232}Th) were taken from ENDF/B-VII.0; and (3) 3 isotopes ({sup 1}H, {sup 238}U and {sup 239}Pu) were taken from JENDL-3.3. For 6 light nuclei ({sup 4}He, {sup 6,7}Li, {sup 9}Be, {sup 10}B, {sup 12}C), only partial cross section covariance results were obtained, additional work is needed and they do not report the results here. Likewise, the cross section covariances for {sup 235}U, which they recommend to take from JENDL-3.3, will be included once the multigroup processing is successfully completed. Covariances for the average number of neutrons per fission, total {nu}-bar, are provided for 10 actinides identified as priority by SG26. Further work is needed to resolve some of the issues and to produce covariances for the full set of 52 materials.

  17. Identification of the contamination source of plutonium in environmental samples with isotopic ratios determined by inductively coupled plasma mass spectrometry and alpha-spectrometry

    International Nuclear Information System (INIS)

    Concentrations of 239+249Pu in environmental samples were determined by ICP-MS and α spectrometry, showing consistent results, which suggests an applicability of ICP-MS to 239Pu and 240Pu measurement. The activity ratios of 238Pu/239+240Pu and 240Pu/239Pu were significantly different in samples from the general environment and near Sellafield reprocessing plants, indicating the usefulness of these ratios for identification of the Pu contamination source. (author)

  18. Rapid analytical technique to identify alpha emitting isotopes in water, air-filters, urine, and solid matrices using a Frisch Grid detector.

    Science.gov (United States)

    Scarpitta, Salvatore C; Miltenberger, Robert P; Gaschott, Robert; Carte, Nina

    2003-04-01

    A 5-inch-diameter Frisch Grid gas-proportional ionization chamber was utilized at Brookhaven National Laboratory (BNL) to rapidly characterize and quantify alpha-emitting actinides in unprocessed water, soil, air-filter, urine, and solid matrices. Instrument calibrations for the various matrices were performed by spiking representative samples with National Institute of Standards and Technology traceable isotopes of 230Th, 232U, 236Pu, and 243Am. Detection efficiencies were typically 15-20% for solid matrices (soil, concrete, filters, dry urine) and 45% for mass-less water samples. Instrument background over a 512-channel alpha-energy range of 3-8 MeV is very low at 0.01 cps. At optimum efficiency, minimum detectable levels of 0.56 mBq Kg(-1), 74 mBq L(-1) and 14.8 mBq filter(-1) were achievable for 40 x 10(-6) Kg soil, 1 x 10(-3) L tap water (or urine), and 4.5 cm diameter air-filter samples, respectively, each counted for 60 min. Data and spectra are presented showing the quality of results obtained using untreated samples obtained from the BNL Graphite Research Reactor Decommissioning Project. These samples contained Bq to MBq per gram amounts of (239,240)Pu, 241Am, and/or (234,235/238)U (as well as other beta/gamma emitters). Data and spectra are also presented for a very finely pulverized and homogeneous U.S. DOE/RESL soil reference standard (spiked with 239Pu, 241Am, and 233U) that was used to assess precision, accuracy, and reproducibility. Although this technique has its limitations, the advantages are (1) minimal sample preparation, (2) no separation chemistry required, (3) no chemical or hazardous waste generated, and (4) ability to immediately characterize and quantify alpha-emitting nuclides in most matrices. The benefits of this technique to the BNL/DOE Project Managers were rapid (1-2 d) turn-around times coupled with significant cost savings, as compared to commercial off-site analyses. PMID:12705448

  19. Plutonium in Soils from Northeast China and Its Potential Application for Evaluation of Soil Erosion

    DEFF Research Database (Denmark)

    Xu, Yihong; Qiao, Jixin; Hou, Xiaolin;

    2013-01-01

    Surface and soil core samples from northeast China were analyzed for Pu isotopes. The measured 240Pu/239Pu atomic ratios and 239 1 240Pu/137Cs activity ratios revealed that the global fallout is the dominant source of Pu and 137Cs at these sites. Migration behavior of Pu varying with land type an...

  20. Determination of plutonium isotopes in seawater reference materials using isotope-dilution ICP-MS.

    Science.gov (United States)

    Zheng, Jian; Yamada, Masatoshi

    2012-09-01

    We analyzed the activities of (239)Pu, (240)Pu, (239+240)Pu, (241)Pu, the ratio of number of atoms (atom ratio) for (240)Pu/(239)Pu, and the activity ratio of (241)Pu/(239+240)Pu in seawater reference materials, IAEA-443 and IAEA-381, using a highly sensitive isotope dilution sector field inductively coupled plasma mass spectrometry method. With a mean chemical yield of 65% determined with (242)Pu as a tracer, we found that the experimentally established values in IAEA-443 for (239)Pu, (240)Pu, (241)Pu and (239+240)Pu activities are almost the same as those in IAEA-381. Regarding the (239+240)Pu activity, we provided the most precise and accurate result among the twelve laboratories, which participated in the interlaboratory comparison. In addition, for the (240)Pu/(239)Pu atom ratio, our results for IAEA-381 (0.2315±0.0008) and IAEA-443 (0.2325±0.0008) are in good agreement with the IAEA information value (0.229±0.006), but have much smaller uncertainty. Since the new seawater reference material, IAEA-443, is commercially available, it can be used not only for method validation for seawater plutonium isotope ratio and activity analysis, but also for more general use as a plutonium isotope standard for mass discrimination correction for other environmental samples.

  1. Intercalibration of selected anthropogenic radionuclides for the GEOTRACES Program

    DEFF Research Database (Denmark)

    Kenna, Timothy C.; Masqué, Pere; Mas, Jose Luis;

    2012-01-01

    As part of the GEOTRACES Program, six laboratories participated in an intercalibration exercise on several anthropogenic radionuclides of interest. The effort was successful for 239,240Pu activity, 240Pu/239Pu isotope ratio, and 137Cs activity measured in filtered seawater samples from the Bermuda...

  2. A pore water study of plutonium in a seasonally anoxic lake

    International Nuclear Information System (INIS)

    Data are presented on the distribution of sup(239,240)Pu in the pore waters of two cores taken from a seasonally anoxic lake. The pore water sup(239,240)Pu profile exhibits a subsurface activity maximum of 230 +- 30 μBq kg-1 in the 3-6 cm interval in June, as compared to an activity of 5 +- 3 μBq kg-1 in the overlying water. The pore water sup(239,240)Pu profile in June follows the solid phase distribution pattern of sup(239,240)Pu and also the pore water distributions of Fe and Mn. Under more reducing conditions in August, pore water sup(239,240)Pu activities drop off to undetectable levels at all depths. This rapid change in the pore water sup(239,240)Pu activity reflects the dynamic nature of Pu diagenesis in these sediments. Potential diffusional fluxes of sup(239,240)Pu into the lake's hypolimnion in June are calculated to be on the order of 2.5 μBq cm-2 y-1. This flux would not be significant in altering the solid phase sup(239,240)Pu inventory (2.8 x 104 μBq cm-2). (author)

  3. Distribution characteristics of ¹³⁷Cs, Pu isotopes and ²⁴¹Am in soil in Korea.

    Science.gov (United States)

    Lee, S H; Oh, J S; Lee, J M; Lee, K B; Park, T S; Lujaniene, G; Valiulis, D; Sakalys, J

    2013-11-01

    Cesium-137, Plutonium isotopes and (241)Am were studied in soil samples collected from Korea between 2006 and 2008 to provide information on the distribution and origin of Pu isotopes and (241)Am. The vertical profiles of radionuclides showed higher activity concentrations at the surface layer and then gradually decreased with depth. A good correlation between (137)Cs and (239,240)Pu was observed, whereas a poor relationship between (137)Cs and (241)Am was found. The (238)Pu/(239,240)Pu, (241)Am/(239,240)Pu and (239,240)Pu/(137)Cs activity ratios were concordant to those of the global fallout ratios. Furthermore, the atomic ratios of (240)Pu/(239)Pu in the samples provided the information of Pu depositional history and the origin of Pu isotopes in Korea.

  4. Fallout Radioactivity in Some Egyptian Lakes Bottom Sediments

    International Nuclear Information System (INIS)

    As a part of the Egyptian environmental radioactivity monitoring program, the fallout radioactivity levels in Qarun, Bardawill and Ed ku lakes bottom sediments have been measured. The specific activities of 137Cs were measured using gamma ray spectrometer based on Hyper pure germanium detector. The specific activities of plutonium isotopes(238Pu, 239+240Pu and 241Pu) were measured using alpha spectrometry based on surface battier detectors and liquid scintillation spectrometry after radiochemical separation. The activity ratios 239+240Pu/137Cs, 239+240Pu/241Pu, and 238Pu/ 239+240Pu were calculated. The results seemed to confirm that fallout radioactivity is mainly due to nuclear weapons testing fallout

  5. Plutonium isotope ratio variations in North America

    Energy Technology Data Exchange (ETDEWEB)

    Steiner, Robert E [Los Alamos National Laboratory; La Mont, Stephen P [Los Alamos National Laboratory; Eisele, William F [Los Alamos National Laboratory; Fresquez, Philip R [Los Alamos National Laboratory; Mc Naughton, Michael [Los Alamos National Laboratory; Whicker, Jeffrey J [Los Alamos National Laboratory

    2010-12-14

    Historically, approximately 12,000 TBq of plutonium was distributed throughout the global biosphere by thermo nuclear weapons testing. The resultant global plutonium fallout is a complex mixture whose {sup 240}Pu/{sup 239}Pu atom ratio is a function of the design and yield of the devices tested. The average {sup 240}Pu/{sup 239}Pu atom ratio in global fallout is 0.176 + 014. However, the {sup 240}Pu/{sup 239}Pu atom ratio at any location may differ significantly from 0.176. Plutonium has also been released by discharges and accidents associated with the commercial and weapons related nuclear industries. At many locations contributions from this plutonium significantly alters the {sup 240}Pu/{sup 239}Pu atom ratios from those observed in global fallout. We have measured the {sup 240}Pu/{sup 239}Pu atom ratios in environmental samples collected from many locations in North America. This presentation will summarize the analytical results from these measurements. Special emphasis will be placed on interpretation of the significance of the {sup 240}Pu/{sup 239}Pu atom ratios measured in environmental samples collected in the Arctic and in the western portions of the United States.

  6. Radionuclide concentrations in bivalves collected along the coastal United States

    International Nuclear Information System (INIS)

    In 1990, the National Oceanic and Atmospheric Administration's National Status and Trends Program initiated a study of artificial radionuclides (241Am, 239+240Pu, 238Pu, 137Cs, 110Ag, 90Sr, 65Zn, 60Co, and 58Co) in oysters and mussels collected along the coastal US. The results of this study show that activation products 110Ag, 65Zn, 60Co and 58Co are sometimes present close to nuclear facilities. In addition, based on a nonparametric Kruskal-Wallis statistical test, it appears that 241Am and 137Cs concentrations as well as 241Am/239+240Pu and 137Cs/40K activity ratios are highest along the West Coast of the US. For 238Pu, 239+240Pu, and 90Sr activities and the other ratios, the differences observed in the distribution of the radionuclides between the various coasts are not statistically significant. There is also a statistical difference between the values of the 239+240Pu/90Sr ratio in oysters vs mussels collected along the East Coast and of the 241Am/239+240Pu ratio between two species of mussels collected along the West Coast. Finally, when the NOAA results for 241Am, 239+240Pu, and 137Cs are compared with those of an earlier (1976-1978) Mussel Watch Program sponsored by the Environmental Protection Agency, the statistical Sign Test generally shows a significant decrease in the concentrations between the mid-1970s and the early 1990s. (author)

  7. Determination of cross-section starting from a decay curve composed of two halves lives; Determinacion de la seccion eficaz a partir de una curva de decaimiento compuesta de dos vidas medias

    Energy Technology Data Exchange (ETDEWEB)

    Martinez Q, E.; Aguilera, E.F. [Instituto Nacional de Investigaciones Nucleares, Departamento del Acelerador, A.P. 18-1027, 11801 Mexico D.F. (Mexico)

    1998-07-01

    It is presented a method developed to determine the cross section of 3n channel of the fusion reaction {sup 6} He + {sup 209} Bi which is based in the {alpha} decay curve of residual nucleus, {sup 212} At. (Author)

  8. Table of radionuclides (Vol. 5 - A = 22 to 244)

    Energy Technology Data Exchange (ETDEWEB)

    Be, M.M.; Chiste, V.; Dulieu, C.; Mougeot, X.; Browne, E.; Chechev, V.; Kuzmenko, N.; Kondev, F.; Luca, A.; Galan, M.; Arinc, A.; Huang, X.

    2010-07-01

    have agreed on the methodologies to be used and the CD-ROM included with this monograph contains the evaluators' comments for each radionuclide in addition to the data tables included in the monograph. This volume includes the evaluation of the following radionuclides: {sup 22}Na, {sup 40}K, {sup 75}Se, {sup 124}Sb, {sup 207}Bi, {sup 211}Bi, {sup 217}At, {sup 222}Ra, {sup 225}Ac, {sup 228}Ra, {sup 231}Th, {sup 232}Th, {sup 233}Th, {sup 233}Pa, {sup 234}Th, {sup 235}U, {sup 237}U, {sup 238}Pu, {sup 240}Pu, {sup 241}Am, {sup 242}Pu, {sup 242}Am, {sup 243}Am, {sup 244}Am, {sup 244}Am{sup m}. Primary recommended data comprise half-lives, decay modes, X-rays, gamma-rays, electron emissions, alpha -and beta- particle transitions and emissions, and their uncertainties

  9. Experimental test of a new neutron threshold detector and its application

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The possibility of using 209Bi as a new threshold detector to measurc high-energy neutrons was investigated for the first time. At the same time the experiment measured successfully the emitted neutron fiuence rate, energy spectrum and dose equivalent rate distributions in the heavy ion target area using a detector complex including 209Bi, 115In, 27A1, 19F and 12C samples.

  10. Role of projectile breakup in {sup 6}He and {sup 6}Li induced fusion reactions around barrier energies

    Energy Technology Data Exchange (ETDEWEB)

    Kumari, Anju; Kharab, Rajesh, E-mail: kharabrajesh@rediffmail.com

    2015-09-15

    The influence of projectile breakup on fusion cross section for {sup 6}He + {sup 209}Bi, {sup 6}He + {sup 64}Zn, {sup 6}Li + {sup 209}Bi and {sup 6}Li + {sup 64}Zn reactions at near barrier energies is studied within the framework of quantum diffusion approach. The breakup does not affect the fusion induced by {sup 6}He, whereas a significant suppression for {sup 6}Li induced reaction is observed in below barrier energy region.

  11. Plutonium Attribute Estimation From Passive NMIS Measurements at VNIIEF

    International Nuclear Information System (INIS)

    Currently, the most relevant application of NMIS for plutonium attribute estimation stems from measurements performed jointly by Oak Ridge National Laboratory (ORNL) and Russian Federal Nuclear Center, All-Russia Scientific Research Institute of Experimental Physics (RFNC-VNIIEF) personnel at RFNC-VNIIEF facilities in Sarov, Russia in June and July 2000. During these measurements at VNIIEF, NMIS was applied in its passive mode to eight unclassified plutonium spherical shells. The shells' properties spanned the following ranges: Composition: (delta)-phase plutonium-metal, constant; Relative 240Pu-content (f240Pu): f240Pu = 1.77% (g 240Pu/g Pu), constant; Inner radius (r1): 10.0 mm (le) r1 (le) 53.5 mm, mean r1 33.5 mm; Outer radius (r2): 31.5 mm (le) r2 (le) 60.0 mm, mean r2 = 46.6 mm; Radial thickness (Δr): 6.4 mm (le) Δr (le) 30.2 mm, mean Δr = 13.1 mm; and Plutonium mass (mPu): 1829 g (le) mPu (le) 4468 g, mean mPu = 3265 g. The features of these measurements were analyzed to extract the attributes of each plutonium shell. Given that the samples measured were of constant composition, geometry, and relative 240Pu-content, each shell is completely described by any two of the following four properties: Inner radius r1; Outer radius r2; Mass m, one of 239Pu mass m239Pu, 240Pu mass m240Pu, or total Pu mass mPu; and Radial thickness Δr. Of these, generally only mass is acknowledged as an attribute of interest; the second property (whichever is chosen) can be considered to be a parameter of the attribute-estimation procedure, much as multiplication is a parameter necessary to accurately estimate fissile mass via most neutron measurements

  12. Aerial deposition of plutonium in mixed forest stands from nuclear fuel reprocessing

    International Nuclear Information System (INIS)

    Concentrations of 238Pu and 239,240Pu were determined in bark, organic matter, and soil samples collected in the summer of 1975 from pine (Pinus taeda) and hardwood (Quercus falcata; Carya tormentosa) stands near a nuclear fuel reprocessing plant at the U.S. Energy Res. and Dev. Admin.'s Savannah River Plant near Aiken, S.C. The results indicated that tree crowns intercepted fallout Pu (Pu-bearing particles) and produced higher Pu concentrations in the organic matter and soil under tree crowns. Higher 239,240Pu concentrations were found under pines than under hardwoods. Plutonium concentrations in the O1 (litter, A00) and O2 (organic matter, A0) layers were higher than those in mineral soil, but most of the Pu was contained in the mineral soil. Higher contents of 239,240Pu were observed near the tree stems than in locations outside of the tree crowns. In pines these values were 163 and 80 nCi 239,240Pu/m2, and in hardwoods, 122 and 80 nCi 239,240Pu/m2, for the respective locations, from the litter to the 15-cm depth. The proportion of 238Pu contained in foliage, litter, and organic matter was greater than for 239,240Pu. However, the latter radionuclides had a greater proportion contained in the mineral soil. This observation is consistent with the more recent releases containing a higher percentage of 238Pu from reprocessing operation. Plutonium concentrations in the 5 to 15 cm depth indicated limited Pu mobility in soil, but 238,240Pu concentrations at this depth were higher near tree stems, suggesting greater mobility perhaps as a result of stem flow

  13. Distributions of Pu isotopes in seawater and bottom sediments in the coast of the Japanese archipelago before and soon after the Fukushima Dai-ichi Nuclear Power Station accident.

    Science.gov (United States)

    Oikawa, Shinji; Watabe, Teruhisa; Takata, Hyoe

    2015-04-01

    A radioactivity measurement survey was carried out from 24 April 2008 to 3 June 2011 to determine the levels of plutonium isotopes and (240)Pu/(239)Pu atom ratios in the marine environments off the sites of commercial nuclear power stations around the Japanese islands; the sampling period extended to two months after the Fukushima Dai-ichi Nuclear Power Station accident. In our previous study (Oikawa et al., 2015), data on Pu isotopes and (241)Am in sediments have already been reported. In this study, we report those on Pu isotopes in seawater as well as sediments, and the characteristics of sediments in addition (e.g., ignition loss and biogenic opals). Concentrations of (239+240)Pu in seawater and bottom sediments remained nearly constant at all sampling locations during the survey period. In addition, no regional differences were observed in the (239+240)Pu concentrations in surface waters. Higher (239+240)Pu concentrations were found in bottom waters at deeper sampling locations, but the (240)Pu/(239)Pu atom ratios were nearly constant regardless of the water depth. Higher (239+240)Pu concentrations were also found in bottom sediments at deeper sampling locations, but vice versa for (240)Pu/(239)Pu atom ratios as reported in the previous report. The sediments samples from deeper locations showed the higher percentage of ignition loss as well as the higher content of biogenic opal. There was likely to be some driving force participating in the transfer of Pu isotopes associated with biogenic substances to the deeper seabed. The present survey showed that the accident at the Fukushima Dai-ichi Nuclear Power Station did not contribute much to the inventory of Pu isotopes in the adjacent sea area.

  14. 239+240pn as a dating marker in lake sediments: An example from Lake Chenghai, China%239+240Pu作为湖泊沉积物计年时标:以云南程海为例

    Institute of Scientific and Technical Information of China (English)

    万国江; 吴丰昌; J Zheng; 万恩源; 廖海清; Y Masatoshi; 王长生

    2011-01-01

    137 CS time mark combined with210Pb dating has been widely applied to recent sedimentation. The 137Cs specific activity is, however, hard to detect after decay for two half-lifes. Due to its comparatively long - term half - life, plutonium from global fallout is expected to provide a dating mark for sedimentation. In the present work, we discuss the vertical distribution of 239 + 240Pu and 137 Cs specific activities, and the 240 pu/239 Pu atom ratio in a sediment core of Lake Chenghai. The distribution pattern of 239 +240pu was similar to those of 137Cs specific activities( decay corrected to deposition time)in the sediment core, and also corresponded well with the annual deposition of 137Cs in the northern hemisphere. These results demonstrate that the 239 +240pu specific activity is available to construct recent chronology for lacustrine sediment. In the examined sediment core, the values of 0. 016 for average 239 +24Opu/137Cs activity ratio and 0.012 for ∑239+240Pu/∑ 137Cs, are close to that of global fallout. The vertical variation of 239+240Pu/137Cs activity ratio indicated that the postdepositional transport of plutonium is much less than radiocesium. The average 240Pu/239 Pu atom ratio is 0. 195 ±0. 021, which means plutonium in Lake Chenghai originated from global fallout. The abnormal distribution of 239+240Pu and 137Cs at 8 cm in the sediment core may be explained by the influence of Chernobyl-source radionuclides.%在近代沉积作用领域137Cs时标与210Pb计年结合,获得了广泛而有效的应用.然而,137Cs经过两个半衰期的衰变已难于辩识.环境中的Pu核素具有相对较长的半衰期,也随全球大气扩散而散落于地球表面,可望作为沉积计年的时间标志.通过程海沉积物柱芯中239+240Pu比活度、240Pu/239Pu原子比率及校正到沉积年代的137Cs比活度的对比研究表明:二者比活度的垂直剖面基本相似、239+240pu比活度与北半球137Cs逐年沉降量之间也具有很

  15. Distributions of Pu isotopes in seawater and bottom sediments in the coast of the Japanese archipelago before and soon after the Fukushima Dai-ichi Nuclear Power Station accident

    International Nuclear Information System (INIS)

    A radioactivity measurement survey was carried out from 24 April 2008 to 3 June 2011 to determine the levels of plutonium isotopes and 240Pu/239Pu atom ratios in the marine environments off the sites of commercial nuclear power stations around the Japanese islands; the sampling period extended to two months after the Fukushima Dai-ichi Nuclear Power Station accident. In our previous study (Oikawa et al., 2015), data on Pu isotopes and 241Am in sediments have already been reported. In this study, we report those on Pu isotopes in seawater as well as sediments, and the characteristics of sediments in addition (e.g., ignition loss and biogenic opals). Concentrations of 239+240Pu in seawater and bottom sediments remained nearly constant at all sampling locations during the survey period. In addition, no regional differences were observed in the 239+240Pu concentrations in surface waters. Higher 239+240Pu concentrations were found in bottom waters at deeper sampling locations, but the 240Pu/239Pu atom ratios were nearly constant regardless of the water depth. Higher 239+240Pu concentrations were also found in bottom sediments at deeper sampling locations, but vice versa for 240Pu/239Pu atom ratios as reported in the previous report. The sediments samples from deeper locations showed the higher percentage of ignition loss as well as the higher content of biogenic opal. There was likely to be some driving force participating in the transfer of Pu isotopes associated with biogenic substances to the deeper seabed. The present survey showed that the accident at the Fukushima Dai-ichi Nuclear Power Station did not contribute much to the inventory of Pu isotopes in the adjacent sea area. - Highlights: • Pu concentration off the Japan coast before and after FDNPS accident was measured. • No regional differences were observed in 239+240Pu concentrations in surface waters. • 240Pu/239Pu atom ratios were also nearly identical in seawaters. • There were no significant

  16. Artificial radionuclides in the atmosphere over Lithuania

    Energy Technology Data Exchange (ETDEWEB)

    Lujaniene, G. [Institute of Physics, Nuclear and Environmental Radioactivity Research Laboratory, Savanoriu 231, LT-02300 Vilnius (Lithuania)], E-mail: lujaniene@ar.fi.lt; Aninkevicius, V. [Semiconductor Physics Institute, A. Gostauto 11, LT-01108 Vilnius (Lithuania); Lujanas, V. [Institute of Physics, Nuclear and Environmental Radioactivity Research Laboratory, Savanoriu 231, LT-02300 Vilnius (Lithuania)

    2009-02-15

    Measurements of airborne radioactive aerosol concentration were carried out on the basis of 1-3 days samples after the Chernobyl disaster and during the period of 1992-2003. Transport of 'hot' particles of different composition resulted in the high activity concentrations of {sup 137}Cs, {sup 238}Pu, {sup 239,240}Pu and {sup 241}Am in the atmosphere in Vilnius at the end of April 1986. The {sup 240}Pu/{sup 239}Pu atom ratio showed clear evidence of non-global plutonium originating from the Chernobyl accident in the atmosphere over Lithuania. The {sup 240}Pu/{sup 239}Pu atom ratio ranged from 0.14 to 0.40 in monthly samples in Vilnius in 1995-2003. An increase in activity concentration of {sup 137}Cs by a factor of 100 (up to 300 {mu}Bq/m{sup 3}) was found following forest fires in the Ukraine and Belarus. However, no transport of the Chernobyl plutonium was observed and the {sup 240}Pu/{sup 239}Pu atom ratio in samples collected during the forest fires was found to be 0.229 and 0.185, respectively. The exponential decrease in the {sup 240}Pu/{sup 239}Pu atom ratio from 0.30 to 0.19 (mean values) was observed in 1995-2003.

  17. Almost twenty years' search of transuranium isotopes in effluents discharged to air from nuclear power plants with VVER reactors.

    Science.gov (United States)

    Hölgye, Z; Filgas, R

    2006-04-01

    Airborne effluents of 5 stacks (stacks 1-5) of three nuclear power plants, with 9 pressurized water reactors VVER of 4,520 MWe total power, were searched for transuranium isotopes in different time periods. The search started in 1985. The subject of this work is a presentation of discharge data for the period of 1998-2003 and a final evaluation. It was found that 238Pu, 239,240Pu, 241Am, 242Cm, and 244Cm can be present in airborne effluents. Transuranium isotope contents in most of the quarterly effluent samples from stacks 2, 4 and 5 were not measurable. Transuranium isotopes were present in the effluents from stack l during all 9 years of the study and from stack 3 since the 3rd quarter of 1996 as a result of a defect in the fuel cladding. A relatively high increase of transuranium isotopes in effluents from stack 3 occurred in the 3rd quarter of 1999, and a smaller increase occurred in the 3rd quarter of 2003. In each instance 242Cm prevailed in the transuranium isotope mixtures. 238Pu/239,240Pu, 241Am/239,240Pu, 242Cm/239,240Pu, and 244Cm/239,240Pu ratios in fuel for different burn-up were calculated, and comparison of these ratios in fuel and effluents was performed.

  18. Transport of (137)Cs, (241)Am and Pu isotopes in the Curonian Lagoon and the Baltic Sea.

    Science.gov (United States)

    Lujanienė, G; Remeikaitė-Nikienė, N; Garnaga, G; Jokšas, K; Šilobritienė, B; Stankevičius, A; Šemčuk, S; Kulakauskaitė, I

    2014-01-01

    Activities of (137)Cs, (241)Am and (239,240)Pu were analyzed with special emphasis on better understanding of radionuclide transport from land via the Neman River estuaries to the Baltic Sea and behavior in the marine environment. Although activity concentrations of (137)Cs in water samples collected the Baltic Sea were almost 100 times higher as compared to the Curonian Lagoon, its activities in the bottom sediments were found to be comparable. Activity (238)Pu/(239,240)Pu and atom (240)Pu/(239)Pu ratios indicated a different contribution of the Chernobyl-originated Pu to the suspended particulate matter (SPM) and bottom sediments. The largest amount of the Chernobyl-derived Pu was found in the smallest suspended matter particles of 0.2-1 μm in size collected in the Klaipeda Strait in 2011-2012. The decrease of characteristic activity (238)Pu/(239,240)Pu and atom (240)Pu/(239)Pu ratios towards the global fallout ones in surface soil and the corresponding increase of plutonium (Pu) ratios in the suspended particulate matter and bottom sediments have indicated that the Chernobyl-derived Pu, primarily deposited on the soil surface, was washed out and transported to the Baltic Sea. Behavior of (241)Am was found to be similar to that of Pu isotopes.

  19. Current levels of Pu isotopes and {sup 137}Cs at the former Soviet Union`s Semipalantisk nuclear test site

    Energy Technology Data Exchange (ETDEWEB)

    Yamamoto, M. [Kanazawa Univ., Ishikawa (Japan). Low Level Radioactivity Laboratory; Tsumura, A. [National Inst. of Agro-Environmental Sciences, Ibaraki (Japan); Tsukatani, T. [Kyoto Univ. (Japan). Kyoto Institute of Economic Research

    1998-10-01

    This paper is a report on our survey of residual radioactivity in the soil of the Semipalatinsk nuclear test site in the former USSR. The soil was sampled at approximately 30 sites along the roads connecting Kurchatov City, ground zero for the first USSR nuclear test, Balapan, Degelen Mountain and Salzhal settlement. The radioactivity levels of {sup 137}Cs, {sup 238}Pu and {sup 239,240}Pu as well as the {sup 240}Pu/{sup 239}Pu atomic ratios in the soil were determined. Although {sup 137}Cs was within typical environmental levels except for an area near ground zero, {sup 239,240}Pu was at elevated levels contaminated with weapons-grade plutonium in all areas we visited. (orig.)

  20. Estimation of the solubility of radioactive aerosol particles in biological liquids

    International Nuclear Information System (INIS)

    Solubility of aerosol 'hot' particles sampled in 1987 in the town of Pripyat in the simulated lung fluid (SLF) (Gamble or Ringer solution) and in 0.1 M HCl was studied under static conditions. Leaching of radionuclides from the 'hot' particles in SFL decreases in the order 137Cs > 90Sr >> 239+240Pu > 241Am, and in 0.1 M HCl in the order 90Sr > 241Am >> 137Cs > 239+240Pu. The degree of passing into 0.1 M HCl solution for 90Sr and 241Am was estimated at 3.3-21 and 2.7-17%, respectively. Depending on the particle size, 0.06-2.2% of 241Am and 0.2-1.8% of 239+240Pu passes into SLF within 28 days

  1. The study of solubility Chernobyl 'hot' particles in simulated lung fluid

    International Nuclear Information System (INIS)

    The solubility of the aerosol 'hot' particles selected at Pripyat region in 1987 in simulated lung fluid (SLF - Gamble's or Pinger's solutions) and 0,1 M HCl was studied statistically. The result showed that leaching of the radionuclides in SLF decrease in line 137Cs > 90Sr >> 239+240Pu ≥ 241Am and in 0,1 M HCl 90Sr >241Am>> 137Cs ≥ 239+240Pu. In dissolution experiments with 0,1 M HCl estimated the soluble portion of the 90Sr and 241Am as 1,4 - 21,0 and 0,9 - 17,0 % correspondingly. In accordance with the size of the 'hot' particles 0,01 - 0,4 % 241Am and 0,02 - 0,3 % 239+240Pu were dissolve in the SLF during seven days

  2. Spatial statistical analysis of contamination level of 241Am and 239Pu, Thule, North-West Greenland

    Energy Technology Data Exchange (ETDEWEB)

    Strodl Andersen, J. (JSA EnviroStat (Denmark))

    2011-10-15

    A spatial analysis of data on radioactive pollution on land at Thule, North-West Greenland is presented. The data comprises levels of 241Am and 239,240Pu on land. Maximum observed level of 241Am is 2.8x105 Bq m-2. Highest levels were observed near Narsaarsuk. This area was also sampled most intensively. In Groennedal the maximum observed level of 241Am is 1.9-104 Bq m-2. Prediction of the overall amount of 241Am and 239,240Pu is based on grid points within the range from the nearest measurement location. The overall amount is therefore highly dependent on the model. Under the optimal spatial model for Narsaarsuk, within the area of prediction, the predicted total amount of 241Am is 45 GBq and the predicted total amount of 239,240Pu is 270 GBq. (Author)

  3. Fallout of cesium-137 on a forest ecosystem in the vicinity of a nuclear fuel reprocessing plant

    International Nuclear Information System (INIS)

    Forest canopies intercepted airborne radionuclide-bearing particles released by a nuclear fuel reprocessing plant at the Savannah River Plant producing higher concentrations and accumulations of 137Cs, 238Pu and sup(239,240)Pu in the forest litter and mineral soil. This impact resulted in 137Cs contents usually more than double that for the control samples not influenced by the plant release. The variations in accumulation and distribution patterns of 137Cs, 238Pu and sup(239,240)Pu were caused by the apparent greater mobility of 137Cs in the soil profile and the time of deposition of the Pu isotopes. The use of 137Cs as an environmental analog for Pu appears questionable as indicated by inconsistent relationships in samples between 137Cs and 238Pu or 137Cs and sup(239,240)Pu. However, its use looks promising in situations elsewhere where erosional transport mechanism determines the mobility of these radionuclides. (author)

  4. Spatial statistical analysis of contamination level of 241Am and 239Pu, Thule, North-West Greenland

    DEFF Research Database (Denmark)

    Strodl Andersen, Jens

    A spatial analysis of data on radioactive pollution on land at Thule, North-West Greenland is presented. The data comprises levels of 241Am and 239,240Pu on land. Maximum observed level of 241Am is 2.8×105 Bq m-2. Highest levels were observed near Narsaarsuk. This area was also sampled most...... intensively. In Grønnedal the maximum observed level of 241Am is 1.9×104 Bq m-2. Prediction of the overall amount of 241Am and 239,240Pu is based on grid points within the range from the nearest measurement location. The overall amount is therefore highly dependent on the model. Under the optimal spatial...... model for Narsaarsuk, within the area of prediction, the predicted total amount of 241Am is 45 GBq and the predicted total amount of 239,240Pu is 270 GBq....

  5. Plutonium, cesium and uranium series radionuclides in the Hudson River estuary and other environments. Annual technical progress report, December 1, 1979-November 30, 1980

    Energy Technology Data Exchange (ETDEWEB)

    Simpson, H. J.; Trier, R. M.; Olsen, C. R.

    1980-01-01

    Radionuclide activities were measured in a large number of sediment cores and suspended particle samples throughout the salinity range of the Hudson River estuary. Activities of /sup 137/Cs, /sup 134/Cs and /sup 60/Co determined by gamma spectrometry and /sup 239/ /sup 240/Pu and /sup 238/Pu determined by alpha spectrometry indicate reasonably rapid accumulation rates in the sediments of marginal cove areas, and very rapid deposition in the harbor region adjacent to New York City, resulting in /sup 239/ /sup 240/Pu accumulations there more than an order of magnitude greater than the fallout delivery rate. Measurable amounts of reactor-derived /sup 134/Cs and /sup 60/Co are found in nearly al sediment samples containing appreciable /sup 137/Cs between 15 km upstream of Indian Point and the downstream extent of our sampling about 70 km south of the reactor. Fallout /sup 239/ /sup 240/Pu reaching the Hudson appears to be almost completely retained within the systems by particle deposition, while 70 to 90% of the /sup 137/Cs derived from both reactor releases and fallout has been exported to the coastal waters in solution. Activity levels of /sup 239/ /sup 240/Pu in New York harbor sediments indicate a significant source in addition to suspended particles carried down the Hudson. The most likely cause appears to be transport into the estuary of particles from offshore waters having higher specific activities of /sup 239/ /sup 240/Pu. Measurements of fallout /sup 239/ /sup 240/Pu in a saline lake with a high carbonate ion concentration yielded water column activities about two orders of magnitude greater than has been found for fallout plutonium in other continental waters, indicating extensive mobility in some natural water environments. Experiments using lake water suggest that carbonate ion may indeed be a critical factor in regulating plutonium solubility and that low molecular weight complexes are primarily responsible for enhanced plutonium solubility.

  6. Plutonium in the WIPP environment: its detection, distribution and behavior.

    Science.gov (United States)

    Thakur, P; Ballard, S; Nelson, R

    2012-05-01

    The Waste Isolation Pilot Plant (WIPP) is the only operating deep underground geologic nuclear repository in the United States. It is located in southeastern New Mexico, approximately 655 m (2150 ft) below the surface of the Earth in a bedded Permian evaporite salt formation. This mined geologic repository is designed for the safe disposal of transuranic (TRU) wastes generated from the US defense program. Aerosol and soil samples have been collected near the WIPP site to investigate the sources of plutonium in the WIPP environment since the late 1990s, well before WIPP received its first shipment. Activities of (238)Pu, (239+240)Pu and (241)Am were determined by alpha spectrometry following a series of chemical separations. The concentrations of Al and U were determined in a separate set of samples by inductively coupled plasma mass spectrometry. The annual airborne concentrations of (239+240)Pu during the period from 1998 to 2010 show no systematic interannual variations. However, monthly (239+240)Pu particulate concentrations show a typical seasonal variation with a maximum in spring, the time when strong and gusty winds frequently give rise to blowing dust. Resuspension of soil particles containing weapons fallout is considered to be the predominant source of plutonium in the WIPP area. Further, this work characterizes the source, temporal variation and its distribution with depth in a soil profile to evaluate the importance of transport mechanisms affecting the fate of these radionuclides in the WIPP environment. The mean (137)Cs/(239+240)Pu, (241)Am/(239+240)Pu activity ratio and (240)Pu/(239)Pu atom ratio observed in the WIPP samples are consistent with the source being largely global fallout. There is no evidence of any release from the WIPP contributing to radionuclide concentrations in the environment. PMID:22549140

  7. Ultra-trace plutonium determination in small volume seawater by sector field inductively coupled plasma mass spectrometry with application to Fukushima seawater samples.

    Science.gov (United States)

    Bu, Wenting; Zheng, Jian; Guo, Qiuju; Aono, Tatsuo; Tagami, Keiko; Uchida, Shigeo; Tazoe, Hirofumi; Yamada, Masatoshi

    2014-04-11

    Long-term monitoring of Pu isotopes in seawater is required for assessing Pu contamination in the marine environment from the Fukushima Dai-ichi Nuclear Power Plant accident. In this study, we established an accurate and precise analytical method based on anion-exchange chromatography and SF-ICP-MS. This method was able to determine Pu isotopes in seawater samples with small volumes (20-60L). The U decontamination factor was 3×10(7)-1×10(8), which provided sufficient removal of interfering U from the seawater samples. The estimated limits of detection for (239)Pu and (240)Pu were 0.11fgmL(-1) and 0.08fgmL(-1), respectively, which corresponded to 0.01mBqm(-3) for (239)Pu and 0.03mBqm(-3) for (240)Pu when a 20L volume of seawater was measured. We achieved good precision (2.9%) and accuracy (0.8%) for measurement of the (240)Pu/(239)Pu atom ratio in the standard Pu solution with a (239)Pu concentration of 11fgmL(-1) and (240)Pu concentration of 2.7fgmL(-1). Seawater reference materials were used for the method validation and both the (239+240)Pu activities and (240)Pu/(239)Pu atom ratios agreed well with the expected values. Surface and bottom seawater samples collected off Fukushima in the western North Pacific since March 2011 were analyzed. Our results suggested that there was no significant variation of the Pu distribution in seawater in the investigated areas compared to the distribution before the accident.

  8. High-level neutron-coincidence-counter (HLNCC) implementation: assay of the plutonium content of mixed-oxide fuel assemblies

    International Nuclear Information System (INIS)

    The portable High-Level Neutron Coincidence Counter is used to assay the 240Pu-effective loading of a reference mixed-oxide fuel assembly by neutron coincidence counting. We have investigated the effects on the coincidence count rate of the total fuel loading (UO2 + PuO2), the fissile loading, the fuel rod diameter, and the fuel rod pattern. The coincidence count rate per gram of 240Pu-effective per centimeter is primarily dependent on the total fuel loading of the assembly; the higher the loading, the higher the coincidence count rate. Detailed procedures for the assay of mixed-oxide fuel assemblies are developed

  9. A certified reference material for radionuclides in the water sample from Irish Sea (IAEA-443)

    DEFF Research Database (Denmark)

    Pham, M.K.; Betti, M.; Povinec, P.P.;

    2011-01-01

    A new certified reference material (CRM) for radionuclides in sea water from the Irish sea (IAEA-443) is described and the results of the certification process are presented. Ten radionuclides (3H, 40K, 90Sr, 137Cs, 234U, 235U, 238U, 238Pu, 239+240Pu and 241Am) have been certified, and information...... values on massic activities with 95% confidence intervals are given for four radionuclides (230Th, 232Th, 239Pu and 240Pu). Results for less frequently reported radionuclides (99Tc, 228Th, 237Np and 241Pu) are also reported. The CRM can be used for quality assurance/quality control of the analysis...

  10. Certified Reference Material IAEA-446 for radionuclides in Baltic Sea seaweed

    DEFF Research Database (Denmark)

    Pham, M.K.; Benmansour, M.; Carvalho, F.P.;

    2014-01-01

    A Certified Reference Material (CRM) for radionuclides in seaweed (Fucus vesiculosus) from the Baltic Sea (IAEA-446) is described and the results of the certification process are presented. The 40K, 137Cs, 234U and 239þ240Pu radionuclides were certified for this material, and information values...... for 12 other radionuclides (90Sr, 99Tc, 210Pb (210Po), 226Ra, 228Ra, 228Th, 230Th, 232Th, 235U, 238U, 239Pu and 240Pu) are presented. The CRM can be used for Quality Assurance/Quality Control of analysis of radionuclides in seaweed and other biota samples, as well as for development and validation...

  11. Transport process of Pu isotope in marginal seas of the western North Pacific Ocean

    Energy Technology Data Exchange (ETDEWEB)

    Yamada, Masatoshi [Department of Radiation Chemistry, Institute of Radiation Emergency Medicine, Hirosaki University, Hirosaki, 036-8564, Aomori (Japan); Zheng, Jian [Research Center for Radiation Protection, National Institute of Radiological Sciences, 4-9-1 Anagawa, Inage, 263-8555, Chiba (Japan)

    2014-07-01

    Significant quantities of Pu isotopes have been released into the marine environment as the result of atmospheric nuclear weapons testing. Most radionuclides globally dispersed in atmospheric nuclear weapons testing were released into the environment during the 1950's and 1960's. In the western North Pacific Ocean, the principal source can be further distinguished as two distinct sources of Pu: close-in tropospheric fallout from nuclear weapons testing at the Pacific Proving Grounds (PPG) in the Marshall Islands and global stratospheric fallout. Since the {sup 240}Pu/{sup 239}Pu atom ratio is characteristic for the Pu emission source, information on Pu isotopic signature is very useful to better understand the transport process in the oceans and to identify the sources of Pu. The mean atom ratio of {sup 240}Pu/{sup 239}Pu from the global stratospheric fallout is 0.180 ±0.014 based on soil sample data, whereas that from close-in tropospheric fallout from the PPG is 0.33 - 0.36. The {sup 240}Pu/{sup 239}Pu atom ratios in seawater samples collected in marginal seas of the western North Pacific Ocean will provide important and useful data for understanding the process controlling Pu transport and for distinguishing future Pu sources. The objectives of this study were to measure the {sup 239+240}Pu concentrations and {sup 240}Pu/{sup 239}Pu atom ratios in seawater from the Sea of Okhotsk, Japan Sea, South China Sea and Sulu Sea and to discuss the transport process of Pu. Large-volume seawater samples (250 L each) were collected from the surface to the bottom in marginal seas of the western North Pacific Ocean with acoustically triggered quadruple PVC sampling bottles during the R/V Hakuho-Maru cruise. The {sup 239}Pu and {sup 240}Pu concentrations and {sup 240}Pu/{sup 239}Pu atom ratios were measured with a double-focusing SF-ICP-MS, which was equipped with a guard electrode to eliminate secondary discharge in the plasma and to enhance overall sensitivity. In

  12. High-energy neutron-induced fission cross sections of natural lead and bismuth-209

    OpenAIRE

    Calviño Tavares, Francisco; Cortés Rossell, Guillem Pere; Poch Parés, Agustí; Pretel Sánchez, Carme

    2011-01-01

    The CERN Neutron Time-Of-Flight (n TOF) facility is well suited to measure small neutron- induced ssion cross sections, as those of subactinides. The cross section ratios of natPb and 209Bi relative to 235U and 238U were measured using PPAC detectors. The fragment coincidence method allows to unambiguously identify the ssion events. The present experiment provides the rst results for neutron-induced ssion up to 1 GeV for natPb and 209Bi. A good agreement with previous exper...

  13. Discharge patterns of radionuclides and the influence of early diagenesis in a salt-marsh of the Ribble Estuary, NW England

    International Nuclear Information System (INIS)

    Routine discharges of low level liquid radioactive waste from British Nuclear Fuels plc (BNFL) at Sellafield and Springfield have resulted in enhanced levels of radionuclides in sediments of the Ribble Estuary, NW England, UK. The variations in radionuclide concentrations (137Cs, 230Th, 232Th, 238U, 239,240Pu and 241Am) with depth were analysed in order to investigate historical discharge trends. The influence of early diagenesis in terms of radionuclide mobility was established by considering geochemical associations of radionuclides through the depth profile. A core from Longton Marsh was analysed by gamma-spectrometry and alpha-spectrometry. Major/trace metal and total organic carbon determinations were also made. Sequential extractions were employed in order to specify radionuclide phase associations. Distinct subsurface maxima were present for 137Cs, 241Am and 239,240Pu with activities as high as 4500 Bq kg-1 for 137Cs and 800 Bq kg-1 for 241Am. Thorium-230 and 238U exhibited complex activity profiles with depth. 137Cs was found associated predominantly with the residual phase at all depths. Thorium-230 and 239,240Pu were mainly associated with the organic and sesquioxide phases with some evidence to suggest that plutonium had undergone a phase redistribution below the sediment surface. Caesium-137, 230Th and 239,240Pu were deemed useful in terms of establishing core chronologies. (author)

  14. Distribution of Pu isotopes and {sup 137}Cs in and around the former soviet union`s Semipalatinsk nuclear test site

    Energy Technology Data Exchange (ETDEWEB)

    Yamamoto, Masayoshi [Kanazawa Univ., Tatsunokuchi, Ishikawa (Japan). Low Level Radioactivity Laboratory; Hoshi, Masaharu; Takada, Jun; Tsukatani, Tsuneo; Sekerbaev, A.Kh.; Busev, B.I.

    1999-03-01

    This paper is a report on our survey of residual radioactivity, Pu isotopes and {sup 137}Cs, within and without the territory of the Semipalatinsk nuclear test site. Soil samples within the test site were collected at approximately 30 sites along the roads connecting Kurchatov City, ground zero for the first USSR nuclear test, Balapan, Degelen Mountain and Salzhal settlement. Furthermore, outside the test site, the soil was sampled at about 20 sites, including some settlements (Mostik, Dolon, Tchagan, etc.), forest and pasture areas, along the roads from Semipalatinsk City to Kurchatov City and north Korosteli settlement. The contamination levels of long-lived radionuclides, {sup 137}Cs, {sup 238}Pu and {sup 239,240}Pu as well as {sup 240}Pu/{sup 239}Pu atomic ratio in the soil were determined by non-destructive {gamma}-spectrometric method and radiochemical separation followed by {alpha}-spectrometric and/or ICP-MS methods, respectively. The results showed that although {sup 137}Cs was within typical environmental levels except for an areas near ground zero and Balapan, {sup 239,240}Pu was elevated levels contaminated with weapons-grade plutonium in all area we visited. From the stepwise leaching of Pu from the soil, 50-80% of total {sup 239,240}Pu in most samples was found to be tightly incorporated into the soil components which might have been melted at time of detonation. (author)

  15. Depositional behaviors of plutonium and thorium isotopes at Tsukuba and Mt. Haruna in Japan indicate the sources of atmospheric dust.

    Science.gov (United States)

    Hirose, K; Igarashi, Y; Aoyama, M; Inomata, Y

    2010-02-01

    Monthly plutonium and thorium depositions at Tsukuba (28m asl) and Mt. Haruna (1370m asl) were measured during 2006 and 2007 (Jan 2006-Dec 2007 at Tsukuba, Nov 2006-Dec 2007 at Mt. Haruna). The monthly (239,240)Pu depositions ranged from 0.044 to 2.67mBq m(-2) at Tsukuba and from 0.05 to 0.9mBq m(-2) at Mt. Haruna during the measurement periods. Monthly (239,240)Pu deposition did not differ markedly between the two sites except in April 2007. Seasonal pattern of monthly (239,240)Pu depositions at both sites showed high in spring and low in summer, and typical of seasonal variations in northeastern Asia. Thorium deposition at Tsukuba was higher than that at Mt. Haruna except in May and June 2007. (230)Th/(232)Th activity ratios were used to partition deposition samples into locally and remotely derived fractions. The results revealed that a major proportion of total (239,240)Pu and Th deposits are derived from remote sources, especially in spring. PMID:19804923

  16. Radioecological observations in the trace-measurement and dosimetric evaluation of radioactive traces in the air; Radiooekologische Beobachtungen bei der Spurenmessung und dosimetrische Bewertung radioaktiver Spuren in der Luft

    Energy Technology Data Exchange (ETDEWEB)

    Walther, Clemens [Leibniz Univ. Hannover (Germany). Inst. fuer Radiooekologie und Strahlenschutz; Wershofen, Herbert [Physikalisch-Technische Bundesanstalt (PTB), Braunschweig (Germany). Arbeitsgruppe Umweltradioaktivitaet

    2014-03-15

    The following topics are dealt with: Weekly measurement of {sup 137}Cs and {sup 40}K, long-time measurement series, natural radioactive nuclides, artificial radioactive nuclides, {sup 85}Kr, {sup 133}Xe, {sup 90}Sr, {sup 137}Cs, and {sup 238-240}Pu, the radioecology of {sup 129}I, dosimetric evaluation of radioactive traces in air. (HSI)

  17. Plutonium and cesium radionuclides in the Hudson River Estuary. Annual technical progress report, December 1, 1974--November 30, 1975

    International Nuclear Information System (INIS)

    We have obtained a large set of gravity cores from the Hudson Estuary through much of the ambient salinity range. A number of core sections have been analyzed for 137Cs, 134Cs, 60Co, and 40K by direct gamma counting, and for 239,240Pu by alpha-spectrometry. The distribution of both 137Cs and 239,240Pu indicates rapid accumulation in marginal cove areas and in the harbor region adjacent to New York City. The distribution of both 137Cs and 239,240Pu in the sediments is quite similar in surface sediments, and the trends with depth in cores are also similar. The ratio of sediment 239,240Pu to 137Cs throughout the sampled salinity range (0-20 0/00) approximates that in fallout, except near the nuclear reactor at Indian Point where releases of 137Cs result in a ratio lower (0.004 to 0.008) than typical of fallout (0.015). Measurement amounts of reactor-derived 134Cs, 60Co, and 54Mn are found in nearly all of the samples containing appreciable 137Cs. These samples were between 15 km upstream of Indian Point reactor site and the downstream extent of our sampling, 70 km south of the reactor

  18. Certified reference material for radionuclides in fish flesh sample IAEA-414 (mixed fish from the Irish Sea and North Sea)

    DEFF Research Database (Denmark)

    Pham, M.K.; Sanchez-Cabeza, J.A.; Povinec, P.P.;

    2006-01-01

    certified for this material. Information on massic activities with 95% confidence intervals is given for six other radionuclides (Sr-90, Pb-210(Po-210), Ra-226, Pu-239, Pu-240 Pu-241). Less frequently reported radionuclides (Tc-99, I-129, Th-228, Th-230 and Np-217) and information on some activity and mass...

  19. Fractionation of plutonium in environmental and bio-shielding concrete samples using dynamic sequential extraction

    DEFF Research Database (Denmark)

    Qiao, Jixin; Hou, Xiaolin

    2010-01-01

    Fractionation of plutonium isotopes (238Pu, 239,240Pu) in environmental samples (i.e. soil and sediment) and bio-shielding concrete from decommissioning of nuclear reactor were carried out by dynamic sequential extraction using an on-line sequential injection (SI) system combined with a specially...... to the treatment and disposal of nuclear waste from decommissioning....

  20. Rapid Determination of Plutonium Isotopes in Environmental Samples Using Sequential Injection Extraction Chromatography and Detection by Inductively Coupled Plasma Mass Spectrometry

    DEFF Research Database (Denmark)

    Qiao, Jixin; Hou, Xiaolin; Roos, Per;

    2009-01-01

    This article presents an automated method for the rapid determination of 239Pu and 240Pu in various environmental samples. The analytical method involves the in-line separation of Pu isotopes using extraction chromatography (TEVA) implemented in a sequential injection (SI) network followed by det...

  1. Further Studies of Plutonium and Americium at Thule, Greenland

    DEFF Research Database (Denmark)

    Aarkrog, Asker; Dahlgaard, Henning; Nilsson, Karen Kristina;

    1984-01-01

    Eleven years after the accidental loss of nuclear weapons in 1968, the fourth scientific expedition to Thule occurred. The estimated inventory of 1 TBq 239,240Pu in the marine sediments was unchanged when compared with the estimate based on the 1974 data. Plutonium from the accident had moved...

  2. Analysis Method of 241Pu Radioactivity by Isotope Dilution-Extraction Liquid Scintillation Spectrometer

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    <正>241Pu is the only pure β emitter with the maximum energy of 20.81 keV in plutonium isotopes of 238Pu, 239Pu, 240Pu and 242Pu, in which 241Pu is mostly specific radioactivity because its half-life is 14.29 a.

  3. Evaluation of the neutron cross sections for Pu-240

    International Nuclear Information System (INIS)

    The present evaluation is proposed to supersede the ENDF/B-V, Revision 2 file for 240Pu. In this work, resonance parameters, cross sections, energy distributions, and angular distributions have been modified. These changes are outlined in detail and appropriate references included. 37 refs., 21 figs., 2 tabs

  4. Sector field inductively coupled plasma mass spectrometry in the elemental and isotopic analysis of lanthanides and actinides

    International Nuclear Information System (INIS)

    Plutonium is one element which is indispensable in identifying the source and for estimating the hazardous effects of rad. The isotopic ratios of plutonium (240Pu/239Pu) and its total concentration in environmental samples were also precisely estimated by high resolution inductively coupled plasma mass spectrometry

  5. Excess plutonium in soil near the Nevada Test Site, USA

    Energy Technology Data Exchange (ETDEWEB)

    Turner, Mary; Rudin, Mark; Cizdziel, James; Hodge, Vernon

    2003-09-01

    Cs and Pu are retained for decades in the upper few centimetres of soil in the Nevada desert. - Two soil profiles were collected from undisturbed areas near the Nevada Test Site (NTS). The activity of {sup 137}Cs in the surface layer of the downwind Queen City Summit profile is three times higher than at the upwind site at Searchlight, NV (41.1{+-}0.6 mBq/g vs. 13.0{+-}0.4 mBq/g), and the {sup 239,240}Pu activity is 100 times greater (51{+-}2 mBq/g vs. 0.52{+-}0.03 mBq/g). An examination of the literature suggests that the {sup 137}Cs/{sup 239,240}Pu and the {sup 239,240}Pu/{sup 238}Pu activity ratios in soils and sediments from the northern hemisphere, due to fallout from atmospheric atomic weapons testing, have generalized values of 36{+-}4 and 30{+-}4, respectively (as of 1 July 1995). Deviations from these values may indicate possible contamination by sources other than fallout. Data from the surface soil of the downwind Queen City Summit profile yield a {sup 137}Cs/{sup 239,240}Pu ratio of 0.81{+-}0.02 and a {sup 239,240}Pu/{sup 238}Pu ratio of 78{+-}6. Clearly, an increase in {sup 239,240}Pu relative to {sup 137}Cs or {sup 238}Pu can account for these observations. There is compelling evidence that this 'excess' {sup 239,240}Pu came from activities at the NTS during the aboveground testing of nuclear devices, more than likely from safety tests, some 40 years ago, and/or during the interim by the wind-driven resuspension of contaminated surface soil on the NTS and its transport off-site. Moreover, the two concentration profiles show that high percentages of both of these elements are retained for decades in the upper few centimeters of soil in Nevada's desert environment.

  6. Accumulation of plutonium from fallout in southern Finns and Lapps

    International Nuclear Information System (INIS)

    The body burden of 239,240Pu and 238Pu from fallout in southern Finns and Lapps was determined by ion exchange and alpha-spectrometry through analyses of autopsy tissue samples. Comparing the body burden against the inhalation and ingestion intake of plutonium of these population groups the fractional absorption factor for plutonium from the human gastrointestinal tract and lungs was estinated. In addition, the determined tissue values were compared with those computed with the aid of the ICRP lung model and plutonium content of surface air in the Helsinki area. The 239,240Pu concentrations per wet weight of tissue descended in the order liver>lymph nodes>bone>lung>testes>muscle. A dependence of plutonium content of tissues on the amount of air inhaled by the person during the fallout period and, thus, on the age of the person, was shown. The skeletal distribution of plutonium in man was roughly similar to that reported for animals. The ratio of 239,240Pu content in vertebrae to that in ribs was 1.4, on the average, and the rib/femur ratio 1.0. The average body burden of 239,240Pu in adult southern Finn and Lapp males was estimated to be 1.2 pCi (44.4 mBq), of which about 51 per cent was located in liver and 40 per cent in skeleton. The estimates for the ingestion and inhalation intake of 239,240Pu during the period 1945-78 were 36 and 18 pCi (1.3, 0.67 Bq) and 540 and 13 pCi (19.9, 0.48 Bq) for southern Finn and Lapp males, respectively. The estimated fractional absorption factor of plutonium in humn GI-tract was of the order (6-9)x10-4 and in lungs (7.5-8.5)x10-2. (author)

  7. 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).

  8. Polonium, uranium and plutonium radionuclides in aquatic and land ecosystem of Poland.

    Science.gov (United States)

    Skwarzec, Bogdan; Strumińska-Parulska, Dagmara I; Boryło, Alicja; Kabat, Krzysztof

    2012-01-01

    This article presents the results of study about distribution, inflow and accumulation of polonium, uranium and plutonium in aquatic and land environment of Poland and the southern Baltic Sea. Radionuclides of (210)Po, (234)U and (238)U as well as (239+240)Pu and (241)Pu are strongly accumulated in Baltic organisms and plants and transferred through the trophic chain. The values of bioconcentration factor (BCF) in Baltic plants and animals are higher for polonium and plutonium in comparison with uranium. The principal source of radionuclides in the southern Baltic Sea is their inflow with rivers. Total annual runoff of polonium, uranium and plutonium from the Vistula and the Odra as well as the Pomeranian rivers were calculated at 95 GBq of (210)Po, 750 GBq of (234+238)U and 160 MBq of (238+239+240)Pu. Seasonal and spatial variability of (210)Po, (238)U and (239+240)Pu levels in the Vistula and the Odra drainage basins were assessed by application of neural-network based classification, especially cluster analysis (CA), principal component analysis (PCA) and self-organizing maps (SOM). The result for the Vistula river indicated correlation between polonium and plutonium as well as polonium and uranium. In the Odra drainage basin, the biggest differences were observed in the case of (238)U. To assess if there are statistically significant differences in mean concentration values of (210)Po, (238)U and (239+240)Pu for the Vistula and the Odra rivers drainage basins were obtained by used of the non-parametric tests. Comparing to the Vistula catchment area, statistically differences concentration of (210)Po and (239+240)Pu in all year was observed for river samples collected on the Odra drainage basin.

  9. 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)

    -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. Weighting spectrum: -- iwt=11 for NJOY-99. Legendre expansion: P6. Thermal scattering: free gas model. Self shielding: sigma-0, infinity, 10000, 1000, 300, 100, 30, 10, 1, 0.1, 1. E-5. Kerma factors are provided. NEA-1707/03: Corrections were made to the continuous inelastic scattering matrices (MT=91), for all nuclides for which this channel is open. This replaces the previous version. 2 - Methods: The nuclear data processing system NJOY-99.67 was used to produce MATXSLIBJ33. It can be further processed using TRANSX-2.15. 3 - Restrictions on the complexity of the problem: Accuracy of pointwise cross-section reconstruction: 0.1%; Upper limit of thermal region: 4.6 eV

  10. A Proposed Reaction Channel for the Synthesis of the Superheavy Nucleus Z=109

    Institute of Scientific and Technical Information of China (English)

    WANG Kun; MA Yu-Gang; MA Guo-Liang; WEI Yi-Bin; CAI Xiang-Zhou; CHEN Jin-Gen; GUO Wei; ZHONG Chen; SHEN Wen-Qing

    2004-01-01

    @@ We apply a statistical-evaporation model (HIVAP) to calculate the cross sections of superheavy elements, mainly about actinide targets and compare with some available experimental data. A reaction channel 30Si + 243Am is proposed for the synthesis of the element Z = 109 and the cross section is estimated.

  11. First results on 236U levels in global fallout.

    Science.gov (United States)

    Sakaguchi, A; Kawai, K; Steier, P; Quinto, F; Mino, K; Tomita, J; Hoshi, M; Whitehead, N; Yamamoto, M

    2009-07-01

    The global fallout (236)U level in soil was deduced from measurements of (236)U, (239+240)Pu and (137)Cs in surface soils which are solely influenced by global fallout. A total of 12 soil cores from the depths of 0-10, 0-20 and 0-30 cm were collected at a flat forest area in Japan. Concentrations of (239+240)Pu and (238)U were determined by alpha-particle spectrometry, while the (236)U/(238)U ratio was measured with accelerator mass spectrometry (AMS). Consistent (236)U/(239)Pu ratios between 0.212 and 0.253 were found. Using this ratio, the total global fallout of (236)U on the earth is estimated to be as much as ca. 900 kg. This knowledge will contribute to the promotion of research on U isotopes, including (236)U, for the fields of geo-resources, waste management and geochemistry. PMID:19406452

  12. Off-Site Radiation Exposure Review Project: Phase 2 soils program

    Energy Technology Data Exchange (ETDEWEB)

    McArthur, R.D.; Miller, F.L. Jr.

    1989-12-01

    To help estimate population doses of radiation from fallout originating at the Nevada Test Site, soil samples were collected throughout the western United States. Each sample was prepared by drying and ball-milling, then analyzed by gamma-spectrometry to determine the amount of {sup 137}Cs it contained. Most samples were also analyzed by chemical separation and alpha-spectrometry to determine {sup 239 + 240}Pu and by isotope mass spectroscopy to determine the ratios of {sup 240}Pu to {sup 239}Pu and {sup 241}Pu to {sup 239}Pu. The total inventories of cesium and plutonium at 171 sites were computed from the results. This report describes the sample collection, processing, and analysis, presents the analytical results, and assesses the quality of the data. 10 refs., 9 figs., 12 tabs.

  13. Determination of plutonium content in TRR spent fuel by nondestructive neutron counting

    Science.gov (United States)

    Chen, Yen-Fu; Sheu, Rong-Jiun; Chiao, Ling-Huan; Yuan, Ming-Chen; Jiang, Shiang-Huei

    2010-07-01

    For the nuclear safeguard purpose, this work aims to nondestructively determine the plutonium content in the Taiwan Research Reactor (TRR) spent fuel rods in the storage pool before the stabilization process, which transforms the metal spent fuel rods into oxide powder. A SPent-fuel-Neutron-Counter (SPNC) system was designed and constructed to carry out underwater scan measurements of neutrons emitting from the spent fuel rod, from which the 240Pu mass in the fuel rod will be determined. The SAS2 H control module of the SCALE 5.1 code package was applied to calculate the 240Pu-to-Pu mass ratio in the TRR spent fuel rod according to the given power history. This paper presents the methodology and design of our detector system as well as the measurements of four TRR spent fuel rods in the storage pool and the comparison of the measured results with the facility declared values.

  14. Methodical supply and results of the radionuclide analysis of natural waters of various Kazakhstan regions, involved in nuclear tests

    International Nuclear Information System (INIS)

    In operation the procedure for determination of the content of artificial radionuclides (239+240)Pu, 90Sr, 137Cs, in natural waters by a method of pre-concentrating with using tracers 236Pu (240Pu), 85Sr, 88Y, 134Cs for determination of a chemical yield is introduced. The concentrating will be carried out from one probe of water of volume up to 30 l. With use of model solutions the optimal requirements of concentrating and metrological parameters are spotted. The procedure utilised for determination of the content of artificial radionuclides in waters of nuclear tests places and contiguous at Kazakhstan territories (Semipalatinsk Nuclear Test Site, Azgir, Lira etc.). The limit of definition of synthetic radionuclides is at a level mBq/l. (author)

  15. Alpha-activities in environmental samples

    International Nuclear Information System (INIS)

    Determination of 239Pu(240Pu) in human lungs from autopsies show for the period 1961 - 1965 lung burdens between 150 - 600 fCi and about 50 fCi/organ for the years 1978/79. In some cases also 241Am and 234U/238U contents were analyzed. Air concentration measurements concerning 239Pu(240Pu) and uranium isotopes were carried out using air filters taken between 1962 - 1979 at a sampling station in Vienna. Additionally performed investigations about the α-activity of typical food stuffs allow a rough estimation of the intake for the general population. Based on statistical data and the results of activity measurements especially of 210Po, 226Ra, 232Th and U(nat) in coals and the ashes, emissions from coal fired stationary sources are discussed. (Author)

  16. Plutonium age dating (production date measurement) by inductively coupled plasma mass spectrometry

    International Nuclear Information System (INIS)

    This paper describes rapid methods for the determination of the production date (age dating) of plutonium (Pu) materials by inductively coupled plasma mass spectrometry (ICP-MS) for nuclear forensic and safeguards purposes. One of the presented methods is a rapid, direct measurement without chemical separation using 235U/239Pu and 236U/240Pu chronometers. The other method comprises a straightforward extraction chromatographic separation, followed by ICP-MS measurement for the 234U/238Pu, 235U/239Pu, 236U/240Pu and 238U/242Pu chronometers. Age dating results of two plutonium certified reference materials (SRM 946 and 947, currently distributed as NBL CRM 136 and 137) are in good agreement with the archive purification dates. (author)

  17. The use of curium neutrons to verify plutonium in spent fuel and reprocessing wastes

    International Nuclear Information System (INIS)

    For safeguards verification of spent fuel, leached hulls, and reprocessing wastes, it is necessary to determine the plutonium content in these items. We have evaluated the use of passive neutron multiplicity counting to determine the plutonium content directly and also to measure the 240Pu/244Cm ratio for the indirect verification of the plutonium. Neutron multiplicity counting of the singles, doubles, and triples neutrons has been evaluated for measuring 240Pu, 244Cm, and 252Cf. We have proposed a method to establish the plutonium to curium ratio using the hybrid k-edge densitometer x-ray fluorescence instrument plus a neutron coincidence counter for the reprocessing dissolver solution. This report presents the concepts, experimental results, and error estimates for typical spent fuel applications

  18. Certified Reference Material IAEA-446 for radionuclides in Baltic Sea seaweed

    International Nuclear Information System (INIS)

    A Certified Reference Material (CRM) for radionuclides in seaweed (Fucus vesiculosus) from the Baltic Sea (IAEA-446) is described and the results of the certification process are presented. The 40K, 137Cs, 234U and 239+240Pu radionuclides were certified for this material, and information values for 12 other radionuclides (90Sr, 99Tc, 210Pb (210Po), 226Ra, 228Ra, 228Th, 230Th, 232Th, 235U, 238U, 239Pu and 240Pu) are presented. The CRM can be used for Quality Assurance/Quality Control of analysis of radionuclides in seaweed and other biota samples, as well as for development and validation of analytical methods, and for training purposes

  19. Determination of plutonium content in TRR spent fuel by nondestructive neutron counting

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Y.-F. [Department of Engineering and System Science, National Tsing Hua University, 101, Sec. 2, Kung Fu Road, Hsinchu 30013, Taiwan (China); Sheu, R.-J. [National Synchrotron Radiation Research Center, 101 Hsin-Ann Road, Hsinchu Science Park, Hsinchu 30076, Taiwan (China); Chiao, L.-H.; Yuan, M.-C. [Institute of Nuclear Energy Research, 1000, Wenhua Road, Jiaan Village, Longtan Township, Taoyuan County 32546, Taiwan (China); Jiang, S.-H., E-mail: shjiang@mx.nthu.edu.t [Department of Engineering and System Science, National Tsing Hua University, 101, Sec. 2, Kung Fu Road, Hsinchu 30013, Taiwan (China); Institute of Nuclear Engineering and Science, National Tsing Hua University, 101, Sec. 2, Kung Fu Road, Hsinchu 30013, Taiwan (China)

    2010-07-21

    For the nuclear safeguard purpose, this work aims to nondestructively determine the plutonium content in the Taiwan Research Reactor (TRR) spent fuel rods in the storage pool before the stabilization process, which transforms the metal spent fuel rods into oxide powder. A SPent-fuel-Neutron-Counter (SPNC) system was designed and constructed to carry out underwater scan measurements of neutrons emitting from the spent fuel rod, from which the {sup 240}Pu mass in the fuel rod will be determined. The SAS2 H control module of the SCALE 5.1 code package was applied to calculate the {sup 240}Pu-to-Pu mass ratio in the TRR spent fuel rod according to the given power history. This paper presents the methodology and design of our detector system as well as the measurements of four TRR spent fuel rods in the storage pool and the comparison of the measured results with the facility declared values.

  20. Sources and Spatial Distribution of Metal Pollutants in Soils near the El Paso Smelter: A Forensic Study with Pb and Pu Isotopes.

    Science.gov (United States)

    Ketterer, Michael; Moan, Matthew; Gremillion, Paul

    2010-05-01

    Lead and copper smelting has been conducted at El Paso since the late 1800's, and as a result, environmental media near the smelter have become contaminated. A study has been conducted to investigate the sources and spatial distribution of metal pollutants (Pb, Cd, Zn, Hg, As, Cu) and concomitant tracers (Ag, In, Sb, Bi) in soils from the smelter vicinity. Sampled locations were residential and non-residential locations in El Paso (Texas, USA), Anapra (New Mexico, USA) and Ciudad Juarez (Chihuahua, Mexico). Lead isotope studies indicate that the soil Pb is derived from smelting, and is consistent with two-component mixing between lead ores from Chihuahua (northern Mexico) having 206Pb/204Pb of 18.6 - 18.8 and ores from the Hanover, New Mexico (USA) mining district with 206Pb/204Pb of ~ 17.6. The Pb isotope results also exclude other common anthropogenic Pb sources such as paint and gasoline emissions as being major contributors. Concentrations of Hg and Pb of up to 10 and 11,000 ppm were found in surface soils within 1 km of the smelter. The metal concentration results clearly indicate that soils near the smelter ( 10 km distant). A general trend of decreasing concentrations vs. distance from the smelter was also observed. However, the results indicate that metal concentrations vary widely even at a fixed distance from the smelter point source. This phenomenon results from a combination of natural and anthropogenic processes that disturb and re-distribute soils in the surface environment. The site conditions consist of a very arid environment with little vegetation cover that is frequently disturbed by high winds and severe episodic rainfall. To study these effects, we have investigated stratospheric fallout plutonium (239+240Pu) as a proxy measure of disturbed vs. undisturbed soil conditions. The premise is that 'undisturbed' locations will have high 239+240Pu activities, and hence contain most or all of the cumulative deposition inventory of smelter pollutants

  1. Ultratrace and isotope ratios analyses of some radionuclides by ICP-MS

    Energy Technology Data Exchange (ETDEWEB)

    Helal, A.I.; Zahran, N.F.; Abd El-Lateef, A.M.; Mohsen, H.T. [Central Lab. for Elemental and Isotopic Analysis, N.R.C. Atomic Energy Authority, Cairo (Egypt); Amr, M.A. [Central Lab. for Elemental and Isotopic Analysis, N.R.C. Atomic Energy Authority, Cairo (Egypt); Nuclear Physics Dept., N.R.C., Atomic Energy Authority, Cairo (Egypt); Bashter, I.I. [Physics Dept., Faculty of Science, Zagazig Univ. (Egypt); Abbas, Y. [Physics Dept., Faculty of Science, Suez Canal Univ., Ismailia (Egypt)

    2004-07-01

    Extensive work is under way using high resolution-ICP-MS for {sup 90}Sr, {sup 234}U, {sup 235}U, {sup 238}U, {sup 239}Pu, {sup 240}Pu, and {sup 241}Am detection. Sample preparation procedures based on liquid-liquid extraction and ion exchange chromatography were developed. Sr, U, Pu, and Am were separated from their matrix and concentrated to improve the power of detection in the mass spectrometer. A microconcentric nebulizer with a desolvation introduction system (Ardius) is used. Instrumental limits of detection using Sr and U standard solutions are 0.01 ppt and 0.006 ppt for Sr and U, respectively. A study is presented on the mass interferences for the specified radionuclides. In the environmental samples investigated the {sup 90}Sr/{sup 86}Sr isotope ratio is 6.02 x 10{sup -9} and for {sup 240}Pu/{sup 239}Pu the isotope ratio is 0.17. (orig.)

  2. Thule-2003 - Investigation of radioactive contamination

    DEFF Research Database (Denmark)

    Nielsen, Sven Poul; Roos, Per

    2006-01-01

    Analyses of marine and terrestrial samples collected in August 2003 from Bylot Sound at Thule, Northwest Greenland, show that plutonium from nuclear weapons in the American B52 plane, which crashed on the sea ice in January 1968, persists in theenvironment. The highest concentrations of plutonium...... are found in the marine sediments under the location where the plane crashed. The distribution of plutonium in the marine sediment is very inhomogeneous and associated with hot particles withactivities found up to 1500 Bq 239,240Pu. Sediment samples collected in Wolstenholme Fjord north of the accident site...... show plutonium concentrations, which illustrates the redistribution of plutonium after the accident. The total plutonium inventory inthe sediments has been assessed based on systematic analyses considering hot particles. The inventory of 239,240Pu in the sediments within a distance of 17 km from...

  3. Environmental Behaviour of Plutonium Accidentally Released at Thule, Greenland

    DEFF Research Database (Denmark)

    Aarkrog, Asker

    1977-01-01

    The environmental contamination resulting from the B-52 accident in 1968 at Thule was studied by scientific expeditions in 1968, 1970 and 1974. The contamination was mainly confined to the marine environment, where plutonium was preferentially located in the sediments and the benthic fauna....... Plutonium concentrations down through the sediment layers decayed exponentially with a half-depth of 1-2 cm. The horizontal distribution of the plutonium may be described by an exponential expression: mCi 239,240Pn km-2 = 460e-0.28R or by a power function: mCl 239,240Pu km-2 = 370 R-1.2, where R....... From 1968 to 1970 the 239,240Pu concentrations in the biota decreased by an order of magnitude, since 1970 the decrease has been less evident. In 1970 and 1974 there were no indications of increased plutonium concentrations in surface seawater or in sea plants or zooplankton. Higher animals...

  4. Estimated inventory of plutonium and uranium radionuclides for vegetation in aged fallout areas

    International Nuclear Information System (INIS)

    Data are presented pertinent to the contamination of vegetation by plutonium and other radionuclides in aged fallout areas on the Nevada Test Site (NTS) and the Tonopah Test Range (TTR). The standing biomass of vegetation estimated by nondestructive dimensional methods varied from about 200 to 600 g/m2 for the different fallout areas. Estimated inventories of 238Pu, 239Pu, 240Pu, and 235U in plants and their biological effects are discussed

  5. High-level neutron coincidence counter (HLNCC): users' manual

    International Nuclear Information System (INIS)

    This manual describes the portable High-Level Neutron Coincidence Counter (HLNCC) developed at the Los Alamos Scientific Laboratory (LASL) for the assay of plutonium, particularly by inspectors of the International Atomic Energy Agency (IAEA). The counter is designed for the measurement of the effective 240Pu mass in plutonium samples which may have a high plutonium content. The following topics are discussed: principle of operation, description of the system, operating procedures, and applications

  6. Uptake of natural and anthropogenic actinides in vegetable crops grown on a contaminated lake bed

    International Nuclear Information System (INIS)

    Activity concentrations and plant/soil concentration ratios (CRs) of 239,240Pu, 241Am, 244Cm, 232Th, and 238U were determined for three vegetable crops grown on an exposed, contaminated lake bed of a former reactor cooling reservoir in South Carolina, USA. The crops included greens and tubers of turnips (Brassica rapa var. white-globe), bush beans (Phaseolus vulgaris), and husks and kernels of sweet corn (Zea mays var. silver queen). Although all plots were fertilized, some received K2SO4, while others received no K2SO4. The K2SO4 fertilizer treatment generally lowered activity concentrations for 241Am, 244Cm, 232Th and 238U, but differences were statistically significant for 241Am and 244Cm only. Highly significant differences occurred in activity concentrations among actinides and among crops. In general, turnip greens exhibited the highest uptake for each of the actinides measured, while corn kernels had the least. For turnip greens, geometric mean CRs ranged from 2.3×10-3 for 239,240Pu to 5.3×10-2 for 241Am (no K2SO4 fertilizer). For corn kernels, geometric mean CRs ranged from 2.1×10-5 for 239,240Pu and 232Th to 1.5×10-3 for 244Cm (no K fertilizer). In general, CRs across all crops for the actinides were in the order: 244Cm>241Am>238U>232Th >239,240Pu. Lifetime health risks from consuming crops contaminated with anthropogenic actinides were similar to the risks from naturally occurring actinides in the same crops (total ∼2×10-6); however, these risks were only ∼0.3% of the risk from consuming the same crops contaminated with 137Cs. (author)

  7. Accumulation of atmospheric radionuclides and heavy metals in cryoconite holes on an Arctic glacier.

    Science.gov (United States)

    Łokas, Edyta; Zaborska, Agata; Kolicka, Małgorzata; Różycki, Michał; Zawierucha, Krzysztof

    2016-10-01

    Surface of glaciers is covered by mineral and organic dust, together with microorganisms forming cryoconite granules. Despite fact that glaciers and ice sheets constitute significance part of land surface, reservoir of freshwater, and sites of high biological production, the knowledge on the cryoconite granules still remain unsatisfactory. This study presents information on radionuclide and heavy metal contents in cryoconites. Cryoconites collected from the Hans Glacier in SW Spitsbergen reveal high activity concentrations of anthropogenic ((238,239,240)Pu, (137)Cs, (90)Sr) and natural ((210)Pb) radionuclides. The (238)Pu/(239+240)Pu activity ratios in these cryoconites significantly exceed the mean global fallout ratio (0.025). The (238)Pu/(239+240)Pu ranged from 0.064 to 0.118. The (239+240)Pu/(137)Cs varied from 0.011 ± 0.003 to 0.030 ± 0.007. Such activity ratios as observed in these cryoconites were significantly higher than the values characterizing global fallout, pointing to possible contributions of these radionuclides from other sources. Heavy metals (Pb, Cd, Cu, Zn, Fe, and Mn) in cryoconites exceed both UCC concentrations and local rocks' concentrations, particularly for cadmium. The concentration ratios of stable lead isotopes ((206)Pb/(207)Pb, (208)Pb/(206)Pb) were determined to discriminate between the natural and anthropogenic sources of Pb in cryoconites and to confirm the strong anthropogenic contribution to heavy metal deposition in the Arctic. In investigated cryoconite holes, two groups of invertebrates, both extremophiles, Tardigrada and Rotifera were detected. Our study indicate that cryoconites are aggregates of mineral and organic substances on surfaces of glaciers are able to accumulate large amounts of airborne pollutants bound to extracellular polymeric substances secreted by microorganisms.

  8. The AS-76 interlaboratory experiment on the alpha spectrometric determinaion of Pu-238. Part 3: Preparation and characterization of samples

    International Nuclear Information System (INIS)

    Four plutonium samples containing 0.2, 0.8, 1.6 and 0.9 atom % of 238Pu have been prepared for the Interlaboratory Experiment AS-76. Of these three were input solutions from a reprocessing plant. The fourth sample was from a plutonium product solution. These samples have been characterized by two alpha spectrometry laboratories and two mass spectrometry laboratories to certify the ratio of alpha activities 238Pu/(239Pu + 240Pu) and the isotopic composition, respectively

  9. Plutonium release from Fukushima Daiichi fosters the need for more detailed investigations

    OpenAIRE

    Stephanie Schneider; Clemens Walther; Stefan Bister; Viktoria Schauer; Marcus Christl; Hans-Arno Synal; Katsumi Shozugawa; Georg Steinhauser

    2013-01-01

    The contamination of Japan after the Fukushima accident has been investigated mainly for volatile fission products, but only sparsely for actinides such as plutonium. Only small releases of actinides were estimated in Fukushima. Plutonium is still omnipresent in the environment from previous atmospheric nuclear weapons tests. We investigated soil and plants sampled at different hot spots in Japan, searching for reactor-borne plutonium using its isotopic ratio 240Pu/239Pu. By using accelerator...

  10. Ascophyllum nodosum (L.) Le Jolis as a bioindicator of radioactivity in the Irish Sea

    OpenAIRE

    Bourne, G S; Assinder, D J

    1991-01-01

    The response of Ascophyllum nodosum to a sudden increase in radioactivity analogous to a nuclear incident is examined in the field. super(137)Cs, super(241)Am and super(239+240)Pu showed net accumulation with exposure time, unlike natural super(228)Th, which was used as a control. Caesium had the highest accumulation rate followed by americium and finally plutonium. Younger plant sections were found to accumulate all the radionuclides significantly faster than older plant sections. Americium ...

  11. Subroutines to Simulate Fission Neutrons for Monte Carlo Transport Codes

    OpenAIRE

    Lestone, J. P.

    2014-01-01

    Fortran subroutines have been written to simulate the production of fission neutrons from the spontaneous fission of 252Cf and 240Pu, and from the thermal neutron induced fission of 239Pu and 235U. The names of these four subroutines are getnv252, getnv240, getnv239, and getnv235, respectively. These subroutines reproduce measured first, second, and third moments of the neutron multiplicity distributions, measured neutron-fission correlation data for the spontaneous fission of 252Cf, and meas...

  12. FFTF (FAST FLUX TEST FACILITY) REACTOR CHARACTERIZATION PROGRAM ABSOLUTE FISSION RATE MEASUREMENTS

    Energy Technology Data Exchange (ETDEWEB)

    FULLER JL; GILLIAM DM; GRUNDL JA; RAWLINS JA; DAUGHTRY JW

    1981-05-01

    Absolute fission rate measurements using modified National Bureau of Standards fission chambers were performed in the Fast Flux Test Facility at two core locations for isotopic deposits of {sup 232}Th, {sup 233}U, {sup 235}U, {sup 238}U, {sup 237}Np, {sup 239}Pu, {sup 240}Pu, and {sup 241}Pu. Monitor chamber results at a third location were analyzed to support other experiments involving passive dosimeter fission rate determinations.

  13. FFTF (Fast Flux Test Facility) Reactor Characterization Program: Absolute Fission-rate Measurements

    Energy Technology Data Exchange (ETDEWEB)

    Fuller, J.L.; Gilliam, D.M.; Grundl, J.A.; Rawlins, J.A.; Daughtry, J.W.

    1981-05-01

    Absolute fission rate measurements using modified National Bureau of Standards fission chambers were performed in the Fast Flux Test Facility at two core locations for isotopic deposits of {sup 232}Th, {sup 233}U, {sup 235}U, {sup 238}U, {sup 237}Np, {sup 239}Pu, {sup 240}Pu, and {sup 241}Pu. Monitor chamber results at a third location were analyzed to support other experiments involving passive dosimeter fission rate determinations.

  14. Optimization of Heterogeneous Utilization of Thorium in PRWs to Enhance Proliferation Resistance and Reduce Waste

    International Nuclear Information System (INIS)

    Typical pressurized water reactors, although loaded with uranium fuel, produce 225 to 275 kg of plutonium per gigawatt year of operation. Although the spent fuel is highly radioactive, it nevertheless offers a potential proliferation pathway because the plutonium is relatively easy to separate, amounts to many critical masses, and aside from the alpha (n reaction on the 240 Pu isotope) does not present any significant intrinsic barrier to weapon assembly

  15. Fluvial export of radionuclides: impact on sediment storages of the Rhone River and fluxes towards the Mediterranean Sea; Transfert des radionucleides artificiels par voie fluviale: consequences sur les stocks sedimentaires rhodaniens et les exports vers la Mediterranee

    Energy Technology Data Exchange (ETDEWEB)

    Rolland, B

    2006-02-15

    This study deals with the behaviour of trace contaminants originating from chronic liquid releases within fluvial aquatic systems. It focuses on some particle reactive artificial radionuclides that were released by the Marcoule nuclear fuel reprocessing plant during several years mainly prior the end of the nineties and that are still detected in the lower Rhone river. It underlines the decrease of {sup 137}Cs, {sup 238}Pu and {sup 239+240}Pu fluxes to the Mediterranean Sea in relation with the variations in the chronic liquid releases from Marcoule. The role of flood events on radionuclides exports processes is particularly considered. Over the years 2002 to 2004, floods contributed for 67%, 55%, 68%, 49% and 56% of the mean annual fluxes of {sup 137}Cs, {sup 238}Pu and {sup 239+240}Pu and natural {sup 7}Be et {sup 210}Pbxs, although these events only represented 5% of time. The removal, during floods, of sediments contaminated by the Marcoule releases contributes on the average for 19%, 44% and 22% of the annual exports of {sup 137}Cs, {sup 238}Pu and {sup 239+240}Pu towards the Sea. Thus, such sedimentary stocks act as a delayed source term of artificial radioactivity that is currently significant. Determination of the sediments residence times before removal allows to evaluate the Rhone capacity to clear its contaminated stocks. Residence times of 200 years, 100 years and 900 years are estimated to be necessary to totally remove the accumulated {sup 137}Cs, {sup 238}Pu and {sup 239+240}Pu, respectively. The location typologies of sediment storages within fluvial systems are also specified. These location are represented on one hand by dams, and on the other hand by river banks and oxbow lakes. Stocks accumulated in dams seem to be removed more easily than those trapped in banks. (author)

  16. Optimization of Heterogeneous Utilization of Thorium in PRWs to Enhance Proliferation Resistance & Reduce Waste

    Energy Technology Data Exchange (ETDEWEB)

    Mujid Kazimi

    2003-12-18

    Typical pressurized water reactors, although loaded with uranium fuel, produce 225 to 275 kg of plutonium per gigawatt year of operation. Although the spent fuel is highly radioactive, it nevertheless offers a potential proliferation pathway because the plutonium is relatively easy to separate, amounts to many critical masses, and aside from the alpha (n reaction on the 240 Pu isotope) does not present any significant intrinsic barrier to weapon assembly

  17. Radiometric dating

    International Nuclear Information System (INIS)

    The paper on radiometric dating is a chapter in a handbook of Holocene Palaeoecology and Palaeohydrology. This chapter is part of a section on dating methods. Radiocarbon dating is discussed with respect to the apparent ages of lake sediments, seawater, sea creatures and plants. Isotope dating methods for the late Holocene deposits involving 210Pb, 137Cs, sup(239, 240)Pu, 241Am, 32Si and 39Ar are also described. (U.K.)

  18. Depth profile of 236U/238U in soil samples in La Palma, Canary Islands

    OpenAIRE

    Srncik, M.; P. Steier; Wallner, G.

    2011-01-01

    The vertical distribution of the 236U/238U isotopic ratio was investigated in soil samples from three different locations on La Palma (one of the seven Canary Islands, Spain). Additionally the 240Pu/239Pu atomic ratio, as it is a well establish tool for the source identification, was determined. The radiochemical procedure consisted of a U separation step by extraction chromatography using UTEVA® Resin (Eichrom Technologies, Inc.). Afterwards Pu was separated from Th and Np by anion exchange ...

  19. Distribution of Np and Pu in Swedish lichen samples (Cladonia stellaris) contaminated by atmospheric fallout

    Energy Technology Data Exchange (ETDEWEB)

    Lindahl, Patric E-mail: patric.lindahl@radfys.lu.se; Roos, Per; Eriksson, Mats; Holm, Elis

    2004-07-01

    The activity concentrations of {sup 237}Np and the two Pu isotopes, {sup 239}Pu and {sup 240}Pu, were determined in lichen samples (Cladonia stellaris) contaminated by fallout from atmospheric nuclear test explosions and the Chernobyl accident. The samples were collected at 18 locations in Sweden, from north to south, between 1986 and 1988 and analysed with high-resolution inductively coupled plasma mass spectrometry (HR-ICP-MS) and alpha spectrometry. Data on the activity ratios {sup 238}Pu/{sup 239+240}Pu and {sup 134}Cs/{sup 137}Cs measured previously were also included in this study for comparison. The {sup 237}Np activity concentration ranged from 0.08{+-}0.01 to 2.08{+-}0.17 mBq kg{sup -1}, depending on the location of the sampling site and time of collection. The {sup 239+240}Pu activity concentration ranged from 0.09{+-}0.01 to 4.09{+-}0.15 Bq kg{sup -1}, with the {sup 240}Pu/{sup 239}Pu atomic ratio ranging between 0.16{+-}0.01 and 0.44{+-}0.03, the higher ratios indicating a combination of weapons test fallout and Chernobyl fallout. The {sup 237}Np/{sup 239}Pu atomic ratios ranged between 0.06{+-}0.01 and 0.42{+-}0.04, the lower ratios indicating combination of weapons test fallout and Chernobyl fallout. At a well-defined sampling site at Lake Rogen (62.32 deg. N, 12.38 deg. E), additional lichen samples were collected between 1987 and 1998 to study the distribution of Np and Pu in different layers. The concentrations of the two elements follow each other quite well in the profile.

  20. Plutonium emission from the Fukushima accident

    International Nuclear Information System (INIS)

    A strong earthquake and subsequent tsunami on 11th March 2011 initiated a severe accident in units 1 to 4 of Fukushima Dai-ichi nuclear power plant, resulting in substantial releases of radionuclides. While much has since been published 00 environmental contamination and exposure to radio--iodine and radio-caesium, little is known about releases of plutonium and other non-volatile elements. Although the total activities of released 131I, 134Cs and 137Cs are of the same order of magnitude as of the Chernobyl accident in 1986, the contribution of little volatile elements, including Pu, is much smaller in Fukushima fallout. The reason is the different physical nature of the accident sequence which led to a release of some 10-5% of the core inventories only (to be compared with 3.5% from Chernobyl). In this contribution the available data on Pu in Fukushima fallout will be reviewed. Data sources are mainly reports and press releases by Japanese authorities and a few scientific articles. The mean ratio 239+240Pu: 137Cs in the near field around the NPP (mainly part of Fukushima prefecture and districts of adjacent prefectures) can be assumed about 3 x 10-7, to be compared to nearly 0.01 in the vicinity of Chernobyl, down to about 3 x 10 -6 in Central Europe. Isotopic ratios 238Pu: 239+240 Pu are about 2.2 (0.46 and 0.035 in Chemobyl and global fallout, respectively). Activity concentrations of Fukushima- 239+240 Pu in surface soil were found up to above 0.1 Bq/kg d.m. in the immediate vicinity of the Fukushima NPP and about one order of magnitude less in Fukushima city, about 60 km away. The 239+240 Pu activity released into the atmosphere is roughly estimated some 109 Bq (Chemobyl : almost 1014 Bq). (author)

  1. Accumulation of atmospheric radionuclides and heavy metals in cryoconite holes on an Arctic glacier.

    Science.gov (United States)

    Łokas, Edyta; Zaborska, Agata; Kolicka, Małgorzata; Różycki, Michał; Zawierucha, Krzysztof

    2016-10-01

    Surface of glaciers is covered by mineral and organic dust, together with microorganisms forming cryoconite granules. Despite fact that glaciers and ice sheets constitute significance part of land surface, reservoir of freshwater, and sites of high biological production, the knowledge on the cryoconite granules still remain unsatisfactory. This study presents information on radionuclide and heavy metal contents in cryoconites. Cryoconites collected from the Hans Glacier in SW Spitsbergen reveal high activity concentrations of anthropogenic ((238,239,240)Pu, (137)Cs, (90)Sr) and natural ((210)Pb) radionuclides. The (238)Pu/(239+240)Pu activity ratios in these cryoconites significantly exceed the mean global fallout ratio (0.025). The (238)Pu/(239+240)Pu ranged from 0.064 to 0.118. The (239+240)Pu/(137)Cs varied from 0.011 ± 0.003 to 0.030 ± 0.007. Such activity ratios as observed in these cryoconites were significantly higher than the values characterizing global fallout, pointing to possible contributions of these radionuclides from other sources. Heavy metals (Pb, Cd, Cu, Zn, Fe, and Mn) in cryoconites exceed both UCC concentrations and local rocks' concentrations, particularly for cadmium. The concentration ratios of stable lead isotopes ((206)Pb/(207)Pb, (208)Pb/(206)Pb) were determined to discriminate between the natural and anthropogenic sources of Pb in cryoconites and to confirm the strong anthropogenic contribution to heavy metal deposition in the Arctic. In investigated cryoconite holes, two groups of invertebrates, both extremophiles, Tardigrada and Rotifera were detected. Our study indicate that cryoconites are aggregates of mineral and organic substances on surfaces of glaciers are able to accumulate large amounts of airborne pollutants bound to extracellular polymeric substances secreted by microorganisms. PMID:27372266

  2. Total and spontaneous fission half-lives of the uranium and plutonium nuclides

    International Nuclear Information System (INIS)

    The total half-life and the half-life for spontaneous fission are evaluated for the various long-lived nuclides of interest. Recommended values are presented for 232U, 233U, 234U, 235U, 236U, 238U, 236Pu, 238Pu, 239Pu, 240Pu, 241Pu, 242Pu, and 244Pu. The uncertainties are provided at the 95% confidence limit for each of the recommended values

  3. Environmental radioactivity in Greenland in 1979

    International Nuclear Information System (INIS)

    Measurements of fallout radioactivity in Greenland in 1979 are reported. Strontium-90 (and Cesium-137 in most cases) was determined in samples of precipitation, sea water, vegetation, animals, and drinking water. Estimates are given of the mean contents of 90Sr and 137Cs in the human diet in Greenland in 1979. Provisional results of the 239,240Pu and 241Am measurements on samples from the expedition to Thule in August 1979 are presented. (author)

  4. Impact of environmental curium on plutonium migration and isotopic signatures.

    Science.gov (United States)

    Kurosaki, Hiromu; Kaplan, Daniel I; Clark, Sue B

    2014-12-01

    Plutonium (Pu), americium (Am), and curium (Cm) activities were measured in sediments from a former radioactive waste disposal basin located on the Savannah River Site, South Carolina, and in subsurface aquifer sediments collected downgradient from the basin. In situ Kd values (Pu concentration ratio of sediment/groundwater) derived from this field data and previously reported groundwater concentration data compared well to laboratory Kd values reported in the literature. Pu isotopic signatures confirmed multiple sources of Pu contamination. The ratio of (240)Pu/(239)Pu was appreciably lower for sediment samples compared to the associated groundwater. This isotopic ratio difference may be explained by the following: (1) (240)Pu produced by decay of (244)Cm may exist predominantly in high oxidation states (Pu(V)O2(+) and Pu(VI)O2(2+)) compared to Pu derived from the disposed waste effluents, and (2) oxidized forms of Pu sorb less to sediments than reduced forms of Pu. Isotope-specific Kd values calculated from measured Pu activities in the sediments and groundwater indicated that (240)Pu, which is derived primarily from the decay of (244)Cm, had a value of 10 ± 2 mL g(-1), whereas (239)Pu originating from the waste effluents discharged at the site had a value of 101 ± 8 mL g(-1). One possible explanation for the isotope-specific sorption behavior is that (240)Pu likely existed in the weaker sorbing oxidation states, +5 or +6, than (239)Pu, which likely existed in the +3 or +4 oxidation states. Consequently, remediation strategies for radioactively contaminated systems must consider not only the discharged contaminants but also their decay products. In this case, mitigation of Cm as well as Pu will be required to completely address Pu migration from the source term. PMID:25350948

  5. Characterization of U/Pu particles originating from the nuclear weapons accidents at Palomares, Spain, 1966 and Thule, Greenland, 1968

    OpenAIRE

    Lind, O. C.; Salbu, B.; Janssens, K.; Proost, K.; Garcia-Leon, M.; R. Garcia-Tenorio

    2007-01-01

    Following the USAF B-52 bomber accidents at Palomares, Spain in 1966 and at Thule, Greenland in 1968, radioactive particles containing uranium (U) and plutonium (Pu) were dispersed into the environment. To improve long-term environmental impact assessments for the contaminated ecosystems, particles from the two sites have been isolated and characterized with respect to properties influencing particle weathering rates. Low (239)Pu/(235)U (0.62-0.78) and (240)Pu/(239)Pu (0.055-0.061) atom ratio...

  6. Radionuclide concentrations in honey bees from Area G at TA-54 during 1997. Progress report

    International Nuclear Information System (INIS)

    Honey bees were collected from two colonies located at Los Alamos National Laboratory's Area G, Technical Area 54, and from one control (background) colony located near Jamez Springs, NM. Samples were analyzed for the following: cesium (137Cs), americium (241Am), plutonium (238Pu and 239,240Pu), tritium (3H), total uranium, and gross gamma activity. Area G sample results from both colonies were higher than the upper (95%) level background concentration for 238Pu and 3H

  7. LA-ICP-MS for Pu source identification at Mayak PA, the Urals, Russia.

    Science.gov (United States)

    Cagno, S; Hellemans, K; Lind, O C; Skipperud, L; Janssens, K; Salbu, B

    2014-02-01

    Information on Pu in environmental samples is traditionally based on the determination of the (240+239)Pu activity via Alpha Spectrometry (AS). A large number of alpha spectrometry sources (planchettes) containing radiochemically separated Pu are therefore stored worldwide and are available for further analyses. These archive samples represent a resource from which valuable information on isotopic composition of alpha emitters including Pu can be obtained. The relative abundances of Pu isotopes can be used to trace specific Pu sources and characterize the relative contributions of different Pu sources in a sample. Thus, in addition to the total (239+240)Pu activity, determination of the (240)Pu/(239)Pu ratio can provide valuable information on the nature of the Pu emitting sources. The Pu isotopic ratios can be determined by mass spectrometry techniques such as Sector Field Inductively Coupled Plasma Mass Spectrometry (SF-ICPMS) or Accelerator Mass Spectrometry (AMS) that require dissolution and complete destruction of the material deposited on the planchettes. In this study Laser Ablation (LA)-quadrupole-ICP-MS has been employed for the analysis of (239)Pu/(240)Pu ratios from alpha-planchettes prepared from samples originating from the Mayak PA nuclear facility, Russia. The results are compared with data from AMS and show that the (240)Pu/(239)Pu ratios obtained by LA-ICP-MS can be utilized to distinguish weapons-grade Pu from civil reprocessing sources. Moreover, isotope ratio mapping can also be performed across the planchettes, allowing e.g. the visualization of possible inhomogeneities in the Pu-isotope distribution on their surface. Thus, this solid sample technique can be applied to extract additional information from existing archives of samples.

  8. Isotopic compositions of (236)U and Pu isotopes in "black substances" collected from roadsides in Fukushima prefecture: fallout from the Fukushima Dai-ichi nuclear power plant accident.

    Science.gov (United States)

    Sakaguchi, Aya; Steier, Peter; Takahashi, Yoshio; Yamamoto, Masayoshi

    2014-04-01

    Black-colored road dusts were collected in high-radiation areas in Fukushima Prefecture. Measurement of (236)U and Pu isotopes and (134,137)Cs in samples was performed to confirm whether refractory elements, such as U and Pu, from the fuel core were discharged and to ascertain the extent of fractionation between volatile and refractory elements. The concentrations of (134,137)Cs in all samples were exceptionally high, ranging from 0.43 to 17.7 MBq/kg, respectively. (239+240)Pu was detected at low levels, ranging from 0.15 to 1.14 Bq/kg, and with high (238)Pu/(239+240)Pu activity ratios of 1.64-2.64. (236)U was successfully determined in the range of (0.28 to 6.74) × 10(-4) Bq/kg. The observed activity ratios for (236)U/(239+240)Pu were in reasonable agreement with those calculated for the fuel core inventories, indicating that trace amounts of U from the fuel cores were released together with Pu isotopes but without large fractionation. The quantities of U and (239+240)Pu emitted to the atmosphere were estimated as 3.9 × 10(6) Bq (150 g) and 2.3 × 10(9) Bq (580 mg), respectively. With regard to U, this is the first report to give a quantitative estimation of the amount discharged. Appreciable fractionation between volatile and refractory radionuclides associated with the dispersal/deposition processes with distance from the Fukushima Dai-ichi Nuclear Power Plant was found.

  9. Plutonium age dating (production date measurement) by inductively coupled plasma mass spectrometry

    OpenAIRE

    Varga, Zsolt; Nicholl, Adrian; Wallenius, Maria; Mayer, Klaus

    2015-01-01

    This paper describes rapid methods for the determination of the production date (age dating) of plutonium (Pu) materials by inductively coupled plasma mass spectrometry (ICP-MS) for nuclear forensic and safeguards purposes. One of the presented methods is a rapid, direct measurement without chemical separation using 235U/239Pu and 236U/240Pu chronometers. The other method comprises a straightforward extraction chromatographic separation, followed by ICP-MS measurement for the 234U/238Pu, 235U...

  10. Individual economical value of plutonium isotopes and analysis of the reprocessing of irradiated fuel

    International Nuclear Information System (INIS)

    An economical analysis of plutonium recycle in a PWR reactor, without any modification, is done, supposing an open market for the plutonium. The individual value of the plutonium isotopes is determined solving a system with four equations, which the unknow factors are the Pu-239, Pu-240, pu-241 and Pu-242 values. The equations are obtained equalizing the cost of plutonium fuel cycle of four different isotope mixture to the cost of the uranium fuel cycle. (E.G.)

  11. 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).

  12. Comparison of Pu and (137)Cs as tracers of soil and sediment transport in a terrestrial environment.

    Science.gov (United States)

    Everett, S E; Tims, S G; Hancock, G J; Bartley, R; Fifield, L K

    2008-02-01

    Following atmospheric nuclear weapons testing in the 1950s and 1960s significant quantities of (137)Cs and (239+240)Pu were deposited worldwide. In recent decades, (137)Cs has been commonly used as a tracer of soil erosion and sedimentation, particularly in the Northern Hemisphere where atomic deposition was three times as great as in the Southern Hemisphere. The relatively short 30-year half-life of this isotope means that its sensitivity as a tracer is rapidly decreasing. In contrast, with half-lives of 24,110 and 6561 years, the sensitivity of the two plutonium isotopes remains essentially the same as when it was deposited. Here we use the technique of Accelerator Mass Spectrometry to demonstrate the potential of anthropogenic Pu as an alternative to (137)Cs as a tracer of soil transport in Australia. We measure an average (137)Cs/(239+240)Pu activity ratio of 27.3+/-1.5 and an average (240)Pu/(239)Pu atom ratio of 0.149+/-0.003, both slightly lower than the global average.

  13. Uranium comparison by means of AMS and ICP-MS and Pu and 137Cs results around an Italian Nuclear Power Plant

    Directory of Open Access Journals (Sweden)

    De Cesare M.

    2015-01-01

    Full Text Available Italy built and commissioned 4 nuclear power plants between 1958-1978, which delivered a total of 1500 MW. All four were closed down after the Chernobyl accident following a referendum in 1987. One of the plants was Garigliano, commissioned in 1959. This plant used a 160 MW BWR1 (SEU of 2.3 % and was operational from 1964 to 1979, when it was switched off for maintenance. It was definitively stopped in 1982, and is presently being decommissioned. We report here details on the chemistry procedure and on the measurements for soil samples, collected up to 4.5 km from the Nuclear Plant. A comparison between uranium (238U concentration as determined by means of AMS (Accelerator Mass Spectrometry and by ICP-MS (Inductively Coupled Plasma-Mass Spectrometry techniques respectively at the ANU (Australian National University and at the Ecowise company in Canberra, Australia, is reported, as well as 236U and 239;240Pu concentration results detected by AMS. 236U/238U and 240Pu/239Pu isotopic ratios by means of AMS are also provided. A contamination from Chernobyl is visible in the 137Cs/239+240Pu activity ratio measurements.

  14. Plutonium, 90Sr and 241Am in human bones from southern and northeastern parts of Poland

    International Nuclear Information System (INIS)

    The paper presents the results of our study on 238Pu, 239Pu, 240Pu, 241Am and 90Sr concentration in human bones carried out on a set of 88 individual samples of central Europe origin. Bone tissue samples were retrieved under surgery while introducing hip joint implants. The conducted surgeries tend to cover either southern or northeastern parts of Poland. While for the southern samples only global fallout was expected to be seen, a mixed global and Chernobyl fallout were to be reflected in the others. Alpha spectrometry was applied to obtain activity concentration for 238Pu, 239+240Pu, 241Am, while liquid scintillation spectrometry for 90Sr and mass spectrometry to receive 240Pu/239Pu mass ratio. Surprisingly enough, and to the contrary to our expectations we could not see any significant differences in either Pu activity or Pu mass ratio between the studied populations. In both populations Chernobyl fraction proved marginal. The results on 90Sr and 241Am confirm similarities between the two examined groups. (author)

  15. Source and long-term behavior of transuranic aerosols in the WIPP environment.

    Science.gov (United States)

    Thakur, P; Lemons, B G

    2016-10-01

    Source and long-term behavior transuranic aerosols ((239+240)Pu, (238)Pu, and (241)Am) in the ambient air samples collected at and near the Waste Isolation Pilot Plant (WIPP) deep geologic repository site were investigated using historical data from an independent monitoring program conducted by the Carlsbad Environmental Monitoring and Research Center and an oversight monitoring program conducted by the management and operating contractor for WIPP at and near the facility. An analysis of historical data indicates frequent detections of (239+240)Pu and (241)Am, whereas (238)Pu is detected infrequently. Peaks in (239+240)Pu and (241)Am concentrations in ambient air generally occur from March to June timeframe, which is when strong and gusty winds in the area frequently give rise to blowing dust. Long-term measurements of plutonium isotopes (1985-2015) in the WIPP environment suggest that the resuspension of previously contaminated soils is likely the primary source of plutonium in the ambient air samples from WIPP and its vicinity. There is no evidence that WIPP is a source of environmental contamination that can be considered significant by any health-based standard. PMID:27394421

  16. Isotopic composition and origin of uranium and plutonium in selected soil samples collected in Kosovo

    Energy Technology Data Exchange (ETDEWEB)

    Danesi, P.R. E-mail: P.R.Danesi@iaea.org; Bleise, A.; Burkart, W.; Cabianca, T.; Campbell, M.J.; Makarewicz, M.; Moreno, J.; Tuniz, C.; Hotchkis, M

    2003-07-01

    Soil samples collected from locations in Kosovo where depleted uranium (DU) ammunition was expended during the 1999 Balkan conflict were analysed for uranium and plutonium isotopes content ({sup 234}U, {sup 235}U, {sup 236}U, {sup 238}U, {sup 238}Pu, {sup 239+240}Pu). The analyses were conducted using gamma spectrometry ({sup 235}U, {sup 238}U), alpha spectrometry ({sup 238}Pu, {sup 239+240}Pu), inductively coupled plasma-mass spectrometry (ICP-MS) ({sup 234}U, {sup 235}U, {sup 236}U, {sup 238}U) and accelerator mass spectrometry (AMS) ({sup 236}U). The results indicated that whenever the U concentration exceeded the normal environmental values ({approx}2 to 3 mg/kg) the increase was due to DU contamination. {sup 236}U was also present in the released DU at a constant ratio of {sup 236}U (mg/kg)/{sup 238}U (mg/kg)=2.6x10{sup -5}, indicating that the DU used in the ammunition was from a batch that had been irradiated and then reprocessed. The plutonium concentration in the soil (undisturbed) was about 1 Bq/kg and, on the basis of the measured {sup 238}Pu/{sup 239+240}Pu, could be entirely attributed to the fallout of the nuclear weapon tests of the 1960s (no appreciable contribution from DU)

  17. Input of transuranic elements through rivers into the Mediterranean Sea

    International Nuclear Information System (INIS)

    Measurements of 137Cs, 238Pu, sup(239+240)Pu and 241Am were carried out on river water as well as its suspended matter collected seasonally in 1977 from two Mediterranean rivers, the Var and the Rhone. The results show that although the concentrations of the soluble fractions of these radionuclides are higher in the Rhone than in the Var, even the elevated concentrations of soluble 137Cs (approximately 40 fCi.ltr-1) and sup(239+240)Pu (approximately 0.1 fCi.ltr-1) in the Rhone are much lower than the average concentrations of these nuclides in Mediterranean surface waters. On the other hand, the concentrations of the nuclides measured in suspended matter are roughly an order of magnitude higher in the Rhone than in the Var. Based on the results of measurements on the two rivers, and assuming that the annual average concentrations of the radionuclides in the Var and the Rhone respectively represent those in radiologically uncontaminated and contaminated Mediterranean rivers, the total inputs of 137Cs, 238Pu, sup(239+240)Pu and 241Am through rivers into the Mediterranean Sea have been estimated. Comparison of these estimated values with the inputs of fallout radionuclides by rain indicates that although local accumulation of transuranic nuclides may be observed on sediments taken from some limited estuarine areas, the geochemical behaviour of transuranic elements in the Mediterranean, as a whole, is exclusively governed today by the fallout input of these elements. (author)

  18. 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

  19. Statistical design and analysis of environmental studies for plutonium and other transuranics at NAEG ''safety-shot'' sites

    International Nuclear Information System (INIS)

    This paper is centered around the use of stratified random sampling for estimating the total amount (inventory) of 239-240Pu and uranium in surface soil at ten ''safety-shot'' sites on the Nevada Test Site (NTS) and Tonopah Test Range (TTR) that are currently being studied by the Nevada Applied Ecology Group (NAEG). The use of stratified random sampling has resulted in estimates of inventory at these desert study sites that have smaller standard errors than would have been the case had simple random sampling (no stratification) been used. Estimates of inventory are given for 235U, 238U, and 239-240Pu in soil at A Site of Area 11 on the NTS. Other results presented include average concentrations of one or more of these isotopes in soil and vegetation and in soil profile samples at depths to 25 cm. The regression relationship between soil and vegetation concentrations of 235U and 238U at adjacent sampling locations is also examined using three different models. The applicability of stratified random sampling to the estimation of concentration contours of 239-240Pu in surface soil using computer algorithms is also investigated. Estimates of such contours are obtained using several different methods. The planning of field sampling plans for estimating inventory and distribution is discussed. (auth)

  20. ESADA Plutonium Program Critical Experiments: Power Distribution Measurements

    Energy Technology Data Exchange (ETDEWEB)

    Akkurt, H.

    2001-06-12

    In 1967, a series of critical experiments were conducted at the Westinghouse Reactor Evaluation Center (WREC) using mixed-oxide (MOX) PuO{sub 2}-UO{sub 2} and/or UO{sub 2} fuels in various lattices and configurations. These experiments were performed under the joint sponsorship of Empire State Atomic Development Associates (ESADA) plutonium program and Westinghouse. The purpose of these experiments was to develop experimental data useful in validating analytical methods used in the design of plutonium-bearing replacement fuel for water reactors. Three different fuel types were used during the experimental program: two MOX fuels and a low-enriched UO{sub 2} fuel. The MOX fuels were distinguished by their {sup 240}Pu content: 8 wt % {sup 240}Pu and 24 wt % {sup 240}Pu. Both MOX fuels contained 2.0 wt % PuO{sub 2} in natural UO{sub 2}. The UO{sub 2} fuel with 2.72 wt % enrichment was used for comparison with the plutonium data and for use in multiregion experiments.

  1. 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)

  2. The isotopic signature of fallout plutonium in the North Pacific

    International Nuclear Information System (INIS)

    Plutonium analyses of a dated coral record from the French Frigate Shoals in the central North Pacific indicate that there are two major sources of Pu in this basin: close-in (tropospheric) fallout from nuclear weapons testing at the Pacific Proving Grounds in the Marshall Islands in the 1950s and global (stratospheric) fallout which peaked in 1962. Furthermore, the 240Pu/239Pu atom ratio of fallout from the Pacific Proving Grounds is characteristically higher (0.24) than that of global fallout Pu (0.18-0.19). Seawater and sediment samples from the North Pacific exhibit a wide range of 240Pu/239Pu values (0.19-0.34), with a trend towards higher ratios in the subsurface waters and sediment. Deep water 240Pu/239Pu ratios are higher in the vicinity of the Marshall Islands relative to stations further from this close-in fallout source. These preliminary data suggest that fallout Pu from the Pacific Proving Grounds is more rapidly removed from the surface waters than is global fallout Pu. Plutonium geochemistry appears to be related to the physical/chemical form of Pu-bearing particles generated by different fallout sources. (author)

  3. Isotopic composition and distribution of plutonium in northern South China Sea sediments revealed continuous release and transport of Pu from the Marshall Islands.

    Science.gov (United States)

    Wu, Junwen; Zheng, Jian; Dai, Minhan; Huh, Chih-An; Chen, Weifang; Tagami, Keiko; Uchida, Shigeo

    2014-03-18

    The (239+240)Pu activities and (240)Pu/(239)Pu atom ratios in sediments of the northern South China Sea and its adjacent Pearl River Estuary were determined to examine the spatial and temporal variations of Pu inputs. We clarified that Pu in the study area is sourced from a combination of global fallout and close-in fallout from the Pacific Proving Grounds in the Marshall Islands where above-ground nuclear weapons testing was carried out during the period of 1952-1958. The latter source dominated the Pu input in the 1950s, as evidenced by elevated (240)Pu/(239)Pu atom ratios (>0.30) in a dated sediment core. Even after the 1950s, the Pacific Proving Grounds was still a dominant Pu source due to continuous transport of remobilized Pu from the Marshall Islands, about 4500 km away, along the North Equatorial Current followed by the transport of the Kuroshio current and its extension into the South China Sea through the Luzon Strait. Using a simple two end-member mixing model, we have quantified the contributions of Pu from the Pacific Proving Grounds to the northern South China Sea shelf and the Pearl River Estuary are 68% ± 1% and 30% ± 5%, respectively. This study also confirmed that there were no clear signals of Pu from the Fukushima Daiichi Nuclear Power Plant accident impacting the South China Sea.

  4. Release of Pu isotopes from the Fukushima Daiichi Nuclear Power Plant accident to the marine environment was negligible.

    Science.gov (United States)

    Bu, Wenting; Fukuda, Miho; Zheng, Jian; Aono, Tatsuo; Ishimaru, Takashi; Kanda, Jota; Yang, Guosheng; Tagami, Keiko; Uchida, Shigeo; Guo, Qiuju; Yamada, Masatoshi

    2014-08-19

    Atmospheric deposition of Pu isotopes from the Fukushima Daiichi Nuclear Power Plant (FDNPP) accident has been observed in the terrestrial environment around the FDNPP site; however, their deposition in the marine environment has not been studied. The possible contamination of Pu in the marine environment has attracted great scientific and public concern. To fully understand this possible contamination of Pu isotopes from the FDNPP accident to the marine environment, we collected marine sediment core samples within the 30 km zone around the FDNPP site in the western North Pacific about two years after the accident. Pu isotopes ((239)Pu, (240)Pu, and (241)Pu) and radiocesium isotopes ((134)Cs and (137)Cs) in the samples were determined. The high activities of radiocesium and the (134)Cs/(137)Cs activity ratios with values around 1 (decay corrected to 15 March 2011) suggested that these samples were contaminated by the FDNPP accident-released radionuclides. However, the activities of (239+240)Pu and (241)Pu were low compared with the background level before the FDNPP accident. The Pu atom ratios ((240)Pu/(239)Pu and (241)Pu/(239)Pu) suggested that global fallout and the pacific proving ground (PPG) close-in fallout are the main sources for Pu contamination in the marine sediments. As Pu isotopes are particle-reactive and they can be easily incorporated with the marine sediments, we concluded that the release of Pu isotopes from the FDNPP accident to the marine environment was negligible.

  5. Radionuclides around nuclear sites in England and Wales

    International Nuclear Information System (INIS)

    Environmental releases of low levels of radioactivity can occur as a consequence of normal operations at nuclear facilities. In England and Wales, the impact of gaseous discharges on the terrestrial environment is monitored routinely by the site operators as well as by Food Science Division of the Ministry of Agriculture, Fisheries and Food. The terrestrial surveillance programme carried out by MAFF Food Science concentrates on agricultural produce to provide assessments of doses to members of the population derived from the consumption of terrestrial foodstuffs. We present here the results of a survey, undertaken in 1993 to supplement the monitoring data of MAFF, of artificial radioactive contamination around eighteen nuclear establishments in England and Wales. Grass and soil samples were used as indicators of environmental contamination at these sites for the radionuclides 137Cs, 90Sr, 239+240Pu and 241Am. When compared to estimated background radionuclide concentrations close to each site, these data reveal that four of the 18 sites have contributed measurable increases to both the 137Cs and 239+240Pu inventory within 500 m outside the boundary fence. Two additional sites showed slight increases above the expected background soil levels of 239+240Pu

  6. Sediment studies at Bikini Atoll part 2. inventories of transuranium elements in surface sediments

    Energy Technology Data Exchange (ETDEWEB)

    Noshkin, V.E.; Eagle, R.J.; Wong, K.M.; Robison, W.L.

    1997-10-01

    This is the second of three reports on Bikini sediment studies, which discusses the concentrations and inventories of {sup 241}Am and {sup 239+240}Pu in sediments from the lagoon. Surface sediment samples were collected from 87 locations over the entire lagoon at Bikini Atoll during 1979. The collections were made to map the distribution of long-lived radionuclides associated with the bottom material and to show what modifications occurred in the composition of the sediment as a result of the testing program. Present inventories for {sup 241}Am and {sup 239+240}Pu in the surface 2 cm of sediment are estimated to be 14 and 17 TBq, respectively. These values are estimated to represent only 14% of the total inventory in the sediment column. Sediment inventories of {sup 239+240}Pu and {sup 241}Am are changing only slowly with time through chemical- physical processes that continuously mobilize small amounts of the transuranics to the water column. The lowest concentrations and inventories are associated with deposits logoonward of the eastern reef.

  7. Thermal flucatuations in a classical theory with shape degrees of freedom for heavy ion collisions

    Science.gov (United States)

    Samaddar, S. K.; Sperber, D.; Zielińska-Pfabe, M.; Sobel, M. I.; Garpman, S. I.

    1981-02-01

    We use a classical dynamical theory with shape degrees of freedom to describe deep inelastic scattering of heavy ions, and include thermal fluctuations by means of the Fokker-Planck equation. The degrees of freedom allow for neck formation, mass transfer, and stretching of the two-nucleus system. Inertias are calculated for these degrees of freedom, and dissipative and conservative forces are used. Fluctuations are calculated by considering the second moments of the distribution and determining a temperature from the excitation energy at each time. We calculate distributions in final energy, angle, charge, and mass, including some double differential cross sections. Results are in good agreement with data. NUCLEAR REACTIONS Classical dynamical model, shape degrees of freedom, Fokker-Planck equation, thermal fluctuations; angular, energy, mass, and charge distributions are calculated for the reactions 209Bi + 84Kr, 209Bi + 136Xe, and 197Au + 63Cu.

  8. Studies of heavy ion reactions and transuranic nuclei. Progress report, August 1, 1979-July 31, 1980. [Univ. of Rochester, New York, 8/1/79-7/31/80

    Energy Technology Data Exchange (ETDEWEB)

    Huizenga, J.R.

    1980-07-01

    The study of heavy-ion reaction mechanisms at the SuperHILAC and LAMPF is reported. Preprints of five articles and manuscripts of four recent conference papers are given, along with complete citations of publications and a list of personnel. Significant work was performed in the following areas: the bombarding energy dependence of the /sup 209/Bi + /sup 136/Xe reaction; the fragment yields for specific Z and A for projectile-like fragments produced in the reaction of 8.3-MeV/u /sup 56/Fe ions with targets of /sup 56/Fe, /sup 165/Ho, /sup 209/Bi, and /sup 238/U; and time distributions of fragments from delayed fission after muon capture for muonic /sup 235/U, /sup 238/U, /sup 237/Np, /sup 239/Pu, and /sup 242/Pu. (RWR)

  9. Studies of heavy ion reactions and transuranic nuclei. Progress report, August 1, 1979-July 31, 1980

    International Nuclear Information System (INIS)

    The study of heavy-ion reaction mechanisms at the SuperHILAC and LAMPF is reported. Preprints of five articles and manuscripts of four recent conference papers are given, along with complete citations of publications and a list of personnel. Significant work was performed in the following areas: the bombarding energy dependence of the 209Bi + 136Xe reaction; the fragment yields for specific Z and A for projectile-like fragments produced in the reaction of 8.3-MeV/u 56Fe ions with targets of 56Fe, 165Ho, 209Bi, and 238U; and time distributions of fragments from delayed fission after muon capture for muonic 235U, 238U, 237Np, 239Pu, and 242Pu

  10. Nuclear structure of 216Ra at high spin

    Indian Academy of Sciences (India)

    S Muralithar; G Rodrigues; R P Singh; R K Bhowmik; P Mukherjee; B Sethi; I Mukherjee

    2012-09-01

    High-spin states of 216Ra ( = 88, = 128) have been investigated through 209Bi(10B, 3n) reaction at an incident beam energy of 55 MeV and 209Bi(11B, 4n) reaction at incident beam energies ranging from 65 to 78 MeV. Based on coincidence data, the level scheme for 216Ra has been considerably extended up to $∼ 33\\hbar$ spin and 7.2 MeV excitation energy in the present experiment with placement of 28 new -transitions over what has been reported earlier. Tentative spin-parity assignments are done for the newly proposed levels on the basis of the DCO ratios corresponding to strong gates. Empirical shell model calculations were carried out to provide an understanding of the underlying nuclear structure.

  11. High-energy Neutron-induced Fission Cross Sections of Natural Lead and Bismuth-209

    CERN Document Server

    Tarrio, D; Carrapico, C; Eleftheriadis, C; Leeb, H; Calvino, F; Herrera-Martinez, A; Savvidis, I; Vlachoudis, V; Haas, B; Koehler, P; Vannini, G; Oshima, M; Le Naour, C; Gramegna, F; Wiescher, M; Pigni, M T; Audouin, L; Mengoni, A; Quesada, J; Becvar, F; Plag, R; Cennini, P; Mosconi, M; Rauscher, T; Couture, A; Capote, R; Sarchiapone, L; Vlastou, R; Domingo-Pardo, C; Dillmann, I; Pavlopoulos, P; Karamanis, D; Krticka, M; Jericha, E; Ferrari, A; Martinez, T; Trubert, D; Oberhummer, H; Karadimos, D; Plompen, A; Isaev, S; Terlizzi, R; Cortes, G; Cox, J; Cano-Ott, D; Pretel, C; Colonna, N; Berthoumieux, E; Vaz, P; Heil, M; Lopes, I; Lampoudis, C; Walter, S; Calviani, M; Gonzalez-Romero, E; Embid-Segura, M; Stephan, C; Igashira, M; Papachristodoulou, C; Aerts, G; Tavora, L; Berthier, B; Rudolf, G; Andrzejewski, J; Villamarin, D; Ferreira-Marques, R; Tain, J L; O'Brien, S; Reifarth, R; Kadi, Y; Neves, F; Poch, A; Kerveno, M; Rubbia, C; Lazano, M; Dahlfors, M; Wisshak, K; Salgado, J; Dridi, W; Ventura, A; Andriamonje, S; Assimakopoulos, P; Santos, C; Voss, F; Ferrant, L; Patronis, N; Chiaveri, E; Guerrero, C; Perrot, L; Vicente, M C; Lindote, A; Praena, J; Baumann, P; Kappeler, F; Rullhusen, P; Furman, W; David, S; Marrone, S; Tassan-Got, L; Gunsig, F; Alvarez-Velarde, F; Massimi, C; Mastinu, P; Pancin, J; Papadopoulos, C; Tagliente, G; Haight, R; Chepel, V; Kossionides, E; Badurek, G; Marganiec, J; Lukic, S; Pavlik, A; Goncalves, I; Duran, I; Alvarez, H; Abbondanno, U; Fujii, K; Milazzo, P M; Moreau, C

    2011-01-01

    The CERN Neutron Time-Of-Flight (n\\_TOF) facility is well suited to measure small neutron-induced fission cross sections, as those of subactinides. The cross section ratios of (nat)Pb and (209)Bi relative to (235)U and (238)U were measured using PPAC detectors. The fragment coincidence method allows to unambiguously identify the fission events. The present experiment provides the first results for neutron-induced fission up to 1 GeV for (nat)Pb and (209)Bi. A good agreement with previous experimental data below 200 MeV is shown. The comparison with proton-induced fission indicates that the limiting regime where neutron-induced and proton-induced fission reach equal cross section is close to 1 GeV.

  12. Transition energy and lifetime for the ground state hyperfine splitting of high Z lithium-like ions

    CERN Document Server

    Shabaev, V M; Tupitsyn, I; Yerokhin, V A; Artemiev, A N; Kühl, T; Tomaselli, M; Zherebtsov, O M

    1998-01-01

    The ground state hyperfine splitting values and the transition probabilities between the hyperfine structure components of high Z lithiumlike ions are calculated in the range Z=49-83. The relativistic, nuclear, QED and interelectronic interaction corrections are taken into account. It is found that the Bohr-Weisskopf effect can be eliminated in a combination of the hyperfine splitting values of the hydrogenlike and lithiumlike ions of an isotope. This gives a good possibility for testing the QED effects in a combination of the strong electric and magnetic fields of the heavy nucleus. Using the experimental result for the 1s hyperfine splitting in ^{209}Bi^{82+}, the 2s hyperfine splitting in ^{209}Bi^{80+} is calculated to be \\Delta E=0.7981(2) eV while the contribution derived from QED constitutes 0.0007(1) eV.

  13. Sensitivity of calculated cross sections on the optical model parameters

    International Nuclear Information System (INIS)

    After reminding the place of the optical model within the framework of nuclear data evaluation we present the sensitivity-analysis of physical quantities deduced from the optical model on the optical potential parameters in the particular case of the interaction n + 209Bi. This analysis is extended to the statistical model used at low incident energies. The consequences on the parameter fitting procedure are described

  14. Formation of superheavy elements in heavy-ion collisions

    OpenAIRE

    Denisov, Vitali

    2001-01-01

    The cold fusion reactions related to 208Pb and 209Bi targets leading to superheavy elements (SHE) with Z=104-112 have been successfully considered in our model recently. Here we briefly discuss this model and extend our consideration to fusion reactions between similar target and projectile. The reactions between weakly deformed target close to Pb and 76Ge, 82Se projectiles are also studied. The available experimental cross-sections are well described. The nucleus-nucleus interaction potentia...

  15. Asymptotic and near-target direct breakup of 6Li and 7Li

    Science.gov (United States)

    Kalkal, Sunil; Simpson, E. C.; Luong, D. H.; Cook, K. J.; Dasgupta, M.; Hinde, D. J.; Carter, I. P.; Jeung, D. Y.; Mohanto, G.; Palshetkar, C. S.; Prasad, E.; Rafferty, D. C.; Simenel, C.; Vo-Phuoc, K.; Williams, E.; Gasques, L. R.; Gomes, P. R. S.; Linares, R.

    2016-04-01

    Background: Li,76 and 9Be are weakly bound against breakup into their cluster constituents. Breakup location is important for determining the role of breakup in above-barrier complete fusion suppression. Recent works have pointed out that experimental observables can be used to separate near-target and asymptotic breakup. Purpose: Our purpose is to distinguish near-target and asymptotic direct breakup of Li,76 in reactions with nuclei in different mass regions. Method: Charged particle coincidence measurements are carried out with pulsed Li,76 beams on 58Ni and 64Zn targets at sub-barrier energies and compared with previous measurements using 208Pb and 209Bi targets. A detector array providing a large angular coverage is used, along with time-of-flight information to give definitive particle identification of the direct breakup fragments. Results: In interactions of 6Li with 58Ni and 64Zn, direct breakup occurs only asymptotically far away from the target. However, in interactions with 208Pb and 209Bi, near-target breakup occurs in addition to asymptotic breakup. Direct breakup of 7Li into α -t is not observed in interactions with 58Ni and 64Zn. However, near-target dominated direct breakup was observed in measurements with 208Pb and 209Bi. A modified version of the Monte Carlo classical trajectory model code platypus, which explicitly takes into account lifetimes associated with unbound states, is used to simulate sub-barrier breakup reactions. Conclusions: Near-target breakup in interactions with Li,76 is an important mechanism only for the heavy targets 208Pb and 209Bi. There is insignificant near-target direct breakup of 6Li and no direct breakup of 7Li in reactions with 58Ni and 64Zn. Therefore, direct breakup is unlikely to suppress the above-barrier fusion cross section in reactions of Li,76 with 58Ni and 64Zn nuclei.

  16. Proton-induced nuclide production in heavy target elements at medium energies

    International Nuclear Information System (INIS)

    Cross sections for the proton-induced production of residual nuclei in natPb and 209Bi were measured for proton energies between 70 MeV and 1.6 GeV. A comparison with calculated cross sections using an INC/E-model, the hybrid model of preequilibrium reactions and a semiempirical formula has been performed showing that for applications which depend on accurate data it is still necessary to measure cross sections. 21 refs., 5 figs

  17. 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

  18. Influence of the angular momentum on nuclear fission

    Energy Technology Data Exchange (ETDEWEB)

    Tanikawa, Masashi [Tokyo Univ. (Japan). Faculty of Science

    1996-03-01

    The effects of the angular momentum on the mechanism of nuclear fission are studied about the reaction systems of compound nucleus of {sup 210}P and {sup 239}Np by the time-of-flight (TOF) method. The reaction systems in this work are {sup 209}Bi+P, {sup 206}Pb+{alpha}, {sup 206}Po+{alpha}, {sup 198}Pt+{sup 12}C, {sup 238}U+P and {sup 232}Th+{sup 7}Li. Target was prepared by vacuum evaporating of each about 100 {mu}g/cm{sup 2} of {sup 209}Bi, {sup 206}Pb and {sup 198}Pt on 10 {mu}g/cm{sup 2} of carbon film. On compound nucleus {sup 210}Po, {sup 210}Po fissions at Ex=45McV but it fissions after 1 or 2 neutrons emission at higher excited energy (Ex=57 MeV). TKE shows almost the same values except higher value of {sup 209}Bi+P. The decreasing tendency of width of TKE distribution with increasing the angular momentum is found at the first time in this work. The effect of the angular momentum on the fission is small in the case of low angular momentum. On the compound nucleus {sup 239}Np, the effects are shown at the asymmetric fission part of the mass distribution. (S.Y.)

  19. Isospin effect on probing nuclear dissipation with fission cross sections

    Science.gov (United States)

    Tian, J.; Ye, W.

    2016-08-01

    Nuclear dissipation retards fission. Using the stochastic Langevin model, we calculate the drop of fission cross section caused by friction over its standard statistical-model value, σfdrop, as a function of the presaddle friction strength for fissioning nuclei 195Bi, 202Bi, and 209Bi as well as for different angular momenta. We find that friction effects on σfdrop are substantially enhanced with increasing isospin of the Bi system and become greater with decreasing angular momentum. Our findings suggest that in experiments, to better constrain the strength of presaddle dissipation through the measurement of fission excitation functions, it is optimal to yield those compound systems with a high isospin and a low spin. Furthermore, we analyze the data of fission excitation functions of 210Po and 209Bi systems, which are populated in p +209Bi and p +208Pb reactions and which have a high isospin and a low spin, and find that Langevin calculations with a presaddle friction strength of (3-5) ×10-21 s-1 describe these experimental fission data very well.

  20. Organic matter controls on iodine and plutonium in atmospheric depositions, streams, and soils in the Fukushima Prefecture

    Science.gov (United States)

    Xu, C.; Zhang, S.; Sugiyama, Y.; Ohte, N.; Ho, Y. F.; Fujitake, N.; Kaplan, D. I.; Yeager, C. M.; Schwehr, K. A.; Santschi, P. H.

    2015-12-01

    In order to assess how environmental factors are controlling the distribution and migration of radioiodine and plutonium that were emitted from the Fukushima Daiichi Nuclear Power Plant (FDNPP) accident, we quantified iodine and 239,240Pu concentration changes in soil samples with different land uses (urban, paddy, deciduous forest and coniferous forest), as well as iodine speciation in surface water and rainwater. A ranking of the land uses by their stable 127I and by their 239,240Pu concentrations were quite distinct from that of 134,137Cs, indicating 137Cs might not be a good geochemical proxy for radioactive 129I or Pu in the long-term, post-FDNPP accident. Being a proxy for the long-term fate of 129I, soil 127I content was well correlated to soil organic matter (SOM) content, regardless of land use type, suggesting that SOM might be an important factor controlling iodine biogeochemistry. Other soil chemical properties, such as Eh and pH, had strong correlations to soil 127I content, but only within a given land use (e.g., within urban soils). Organic carbon (OC) and Eh were positively, and pH was negatively correlated to 127I concentrations in surface water and rain samples. It is also noticeable that 127I in the bulk deposition was concentrated along the rainwater passage likely due to plant evapotranspiration activity, with all inorganic iodine being completely converted to organo-iodine by plant organic matter. 239,240Pu activities of all soil samples were well within the global fallout range, but the Fukushima-derived 239,240Pu was detectable at a distance ~61 km away, NW of FDNPP. However, it is confined to the litter layer, even three years after the FDNPP accident-derived emissions. 239,240Pu activities were significantly correlated with soil OC and nitrogen contents, indicating Pu may be associated with nitrogen-containing SOM, similar to what has been observed at other locations in the United States, e.g., Savannah River Site (SRS) and Rocky Flats

  1. Using sequential extraction techniques to assess the partitioning of plutonium and neptunium-237 from multiple sources in sediments from the Ob River (Siberia).

    Science.gov (United States)

    Kenna, Timothy C

    2009-07-01

    Sequential extraction techniques have been developed to assess partitioning of anthropogenic radionuclides ((240)Pu, (239)Pu, and (237)Np), originating from a variety of sources, as identified by using bulk sediment isotopic composition. Sediments were leached sequentially with a series of six chemical treatments designed to approximate different environmental processes that may occur or to selectively extract trace metals contained in different solid phases of the sediments (i.e., exchangeable, reducible, carbonate, organic, acid leachable, and refractory). Results indicate the majority of Pu and Np is similarly distributed within many of the extracted fractions, with the largest percentage (66-97%) of both elements being observed in sediments treated with buffered citrate dithionite (CDB), which targets easily reduced constituents such as Mn and Fe hydrous oxides. While these results do indicate an association of Pu and Np with redox sensitive elements, the environmental implications are unclear given that the CDB treatment is more extreme than naturally occurring conditions. Minor amounts of Np partition differently from Pu in sediments. The NH(4)-acetate treatment, which is designed to liberate trace metals that are loosely adsorbed onto the surfaces of sedimentary materials such as hydrated iron oxides and humic substances, or present at exchangeable sites in clay minerals, mobilized approximately 12% of the total Np while Pu levels were below detection. The H(2)O(2) treatment, which is designed to liberate trace metals bound to organic matter, mobilized approximately 8 and approximately 1% of Np and Pu, respectively. These results indicate that a minor portion of the total Np may be affected by environmental conditions that have little or no effect on Pu. Between 7 and 24% of the Pu was observed in treatments designed to liberate Pu and Np that are tightly bound to lithogenic phases or refractory silicates. The (240)Pu/(239)Pu observed in accessible and

  2. Translation of selected papers published in Nuclear Constants, No. 3(57), Moscow 1984

    International Nuclear Information System (INIS)

    The document contains the English translation of 6 papers selected for the nuclear data interest, (mainly the determination and the evaluation of the fast fission cross sections of 232Th, 235U, 238U, 237Np, 243Am) which were published in ''Topics in Atomic Science and Technology'', Series Nuclear Constants, No. 3(57), Moscow (1984). The original report was distributed as INDC(CCP)-240/G. Refs, figs and tabs

  3. Measurements of Fission Cross Sections of Actinides

    CERN Multimedia

    Wiescher, M; Cox, J; Dahlfors, M

    2002-01-01

    A measurement of the neutron induced fission cross sections of $^{237}$Np, $^{241},{243}$Am and of $^{245}$Cm is proposed for the n_TOF neutron beam. Two sets of fission detectors will be used: one based on PPAC counters and another based on a fast ionization chamber (FIC). A total of 5x10$^{18}$ protons are requested for the entire fission measurement campaign.

  4. Isoscaling and fission modes in the yields of the Kr and Xe isotopes from photofission of actinides

    Science.gov (United States)

    Drnoyan, J.; Zhemenik, V. I.; Mishinsky, G. V.

    2016-05-01

    Yields of Kr and Xe isotopes in photofission of 232Th, 238U, 237Np, 244Pu, 243Am, and 248Cm were tested for isoscaling dependence. Isoscaling for Kr is revealed. For Xe, isoscaling is found to be affected by the STI and STII fission modes governed by the N = 82 and N = 88 neutron shells. The work was performed at the Flerov Laboratory of Nuclear Reactions, Joint Institute for Nuclear Research (JINR).

  5. Analysis of the evaluated data discrepancies for minor actinides and development of improved evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Ignatyuk, A. [Institute of Physics and Power Engineering, Obninsk (Russian Federation)

    1997-03-01

    The work is directed on a compilation of experimental and evaluated data available for neutron induced reaction cross sections on {sup 237}Np, {sup 241}Am, {sup 242m}Am and {sup 243}Am isotopes, on the analysis of the old data and renormalizations connected with changes of standards and on the comparison of experimental data with theoretical calculation. Main results of the analysis performed by now are presented in this report. (J.P.N.)

  6. 长江口放射性核素Pu的大气湿沉降初步研究%Atmospheric Wet Deposition of Radionuclide Pu in the Changjiang River Estuary Region

    Institute of Scientific and Technical Information of China (English)

    张克新; 潘少明; 徐仪红; 曹立国; 徐伟; 张威; 郝永佩

    2016-01-01

    Anthropogenic radionuclides (137Cs, 90Sr, and Pu isotopes) released from atmospheric nuclear tests, ma-jor nuclear reactor accidents, and other sources can be detected in the environment in most parts of the world. In particular, as a result of atmospheric nuclear explosions, about 15 PBq of 239,240Pu (1 PBq=1015 Bq) and 0.3 PBq of 238Pu have been globally released into the atmosphere. These radionuclides may be useful tracers of environ-mental changes, such as desertification, erosion and sedimentation processes, in terrestrial regions. Further-more, measurements of radionuclide deposition are useful for several purposes, including the assessment of the effects of radiation from anthropogenic radionuclides on humans. They may also find use as indicators of envi-ronmental events. Most of the current investigations focus on the chemical behaviors such as transfer and diffu-sion in environment, but for the atmospheric wet deposition of radionuclide Pu, the publically available report is very limited in China. In this article, we investigated and quantified preliminarily the 239,240Pu atmospheric de-position in the Changjiang River Estuary Region based on the records of 239,240Pu atmospheric deposition and pre-cipitation in Tokyo in Japan. The results indicated that 239,240Pu atmospheric deposition history in the Changjiang River Estuary Region was similar to that of the whole north hemisphere. The cumulative atmospheric deposi-tion inventory of 239,240Pu was estimated to be 34.556 Bq/m2 in 1957-2005. The maximum annual deposition oc-curred in 1963 after the large-scale atmospheric nuclear weapons testing in 1950s-1960s conducted by the Unit-ed States and former USSR. Annual 239,240Pu deposition decreased in the period from 1963 to 1967 according to the stratospheric residence time of nuclear debris. In the 1970s, the radionuclide deposition observed in the Changjiang River Estuary showed no decrease because of a series of American and Chinese atmospheric nucle

  7. Experimental evaluation of admission and disposition of artificial radionuclides including transuranium elements in agricultural plants

    Energy Technology Data Exchange (ETDEWEB)

    Kozhakhanov, T.; Lukashenko, S. [Institute of radiation safety and ecology (Kazakhstan)

    2014-07-01

    Processes of radionuclides migration and transfer to agricultural plants are quite well developed worldwide, but the information on character of accumulation of {sup 241}Am and {sup 239+240}Pu transuranium radionuclides in agricultural plants is still fragmentary. Even in generalized materials of worldwide studies, IAEA guide, accumulation coefficient (AC) can have wide range of values (5-6 orders), no data exists on radionuclides' distribution in different organs of plants and they are given for joined groups of plants and types of soils. That is why the main aim of this work was to obtain basic quantitative parameters of radionuclides' migration in 'soil-plant' system, and firs of all- for transuranium elements.. In 2010 a series of experiments with agricultural plants was started at the territory of the former Semipalatinsk Test Site aimed to investigate entry of artificial radionuclides by crop products in natural climatic conditions. To conduct the experiment for study of coefficient of radionuclides' accumulation by agricultural corps, there was chosen a land spot at the STS territory, characterized by high concentration of radionuclides: {sup 241}Am - n*10{sup 4} Bq/kg, {sup 137}Cs - n*10{sup 3} Bq/kg, {sup 90}Sr - n*10{sup 3} Bq/kg and {sup 239+240}Pu- n*10{sup 5} Bq/kg. As objects of investigation, cultures, cultivated in Kazakhstan have been selected: wheat (Triticum vulgare), barley (Hordeum vulgare), oat (Avena sativa L.), water melon (Citrullus vulgaris), melon (Cucumis melo), potato (Solanum tuberosum), eggplant (Solanum melongena), pepper (Capsicum annuum), tomato (Solanum lycopersicum), sunflower (Helianthus cultus), onion (Allium cepa), carrot (Daucus carota), parsley(Petroselinum vulgare)and cabbage (Brassica oleracea). Investigated plants have been planted within the time limits, recommended for selected types of agricultural plants. Cropping system included simple agronomic and amelioration measures. Fertilizers were not

  8. Experimental evaluation of admission and disposition of artificial radionuclides including transuranium elements in agricultural plants

    International Nuclear Information System (INIS)

    Processes of radionuclides migration and transfer to agricultural plants are quite well developed worldwide, but the information on character of accumulation of 241Am and 239+240Pu transuranium radionuclides in agricultural plants is still fragmentary. Even in generalized materials of worldwide studies, IAEA guide, accumulation coefficient (AC) can have wide range of values (5-6 orders), no data exists on radionuclides' distribution in different organs of plants and they are given for joined groups of plants and types of soils. That is why the main aim of this work was to obtain basic quantitative parameters of radionuclides' migration in 'soil-plant' system, and firs of all- for transuranium elements.. In 2010 a series of experiments with agricultural plants was started at the territory of the former Semipalatinsk Test Site aimed to investigate entry of artificial radionuclides by crop products in natural climatic conditions. To conduct the experiment for study of coefficient of radionuclides' accumulation by agricultural corps, there was chosen a land spot at the STS territory, characterized by high concentration of radionuclides: 241Am - n*104 Bq/kg, 137Cs - n*103 Bq/kg, 90Sr - n*103 Bq/kg and 239+240Pu- n*105 Bq/kg. As objects of investigation, cultures, cultivated in Kazakhstan have been selected: wheat (Triticum vulgare), barley (Hordeum vulgare), oat (Avena sativa L.), water melon (Citrullus vulgaris), melon (Cucumis melo), potato (Solanum tuberosum), eggplant (Solanum melongena), pepper (Capsicum annuum), tomato (Solanum lycopersicum), sunflower (Helianthus cultus), onion (Allium cepa), carrot (Daucus carota), parsley(Petroselinum vulgare)and cabbage (Brassica oleracea). Investigated plants have been planted within the time limits, recommended for selected types of agricultural plants. Cropping system included simple agronomic and amelioration measures. Fertilizers were not used, because the aim of investigation was to obtain basic data on radionuclides

  9. Historical trace element distribution in sediments from the Mississippi River delta

    Science.gov (United States)

    Swarzenski, P.W.; Baskaran, M.; Rosenbauer, R.J.; Orem, W.H.

    2006-01-01

    Five sediment cores were collected on the shelf of the inner Mississippi Bight in June 2003 for a suite of radionuclides to establish geochronologies and trace elements to examine patterns of contaminant deposition and accumulation. Core sites were chosen to reflect a matrix of variable water depths, proximity to the Mississippi River mouth as the primary source for terrigenous particles, and extent and duration of summertime water column hypoxia. The vertical distribution of 239,240Pu and 210Pbxs (= 210Pbtotal - 226Ra) provided reliable geochronological age constraints to develop models for mass accumulation rates and historic trace element inputs and variations. Mass accumulation rates ranged from 0.27 to 0.87 g cm-2 yr-1 and were internally consistent using either 210Pbxs or 239,240Pu. Measured inventories of 137Cs, 239,240Pu, and 210Pbxs were compared to atmospheric deposition rates to quantify potential sediment focusing or winnowing. Observed variability in calculated mass accumulation rates may be attributed foremost to site-specific proximity to the river mouth (i.e., sediment source), variability in water depth, and enhanced sediment focusing at the Mississippi River canyon site. Trace element concentrations were first normalized to Al, and then Al-normalized enrichment factors (ANEF) were calculated based on preanthropogenic and crustal trace element abundances. These ANEFs were typically > 1 for V and Ba, while for most other elements studied, either no enrichment or depletion was observed. The enrichment of Ba may be related, in part, to the seasonal occurrence of oxygen-depleted subsurface waters off the Mississippi River delta, as well as being an ubiquitous by-product of the petroleum industry. ?? 2006 Estuarine Research Federation.

  10. Long-lived radionuclides in residues from operation and decommissioning of nuclear power plants

    Science.gov (United States)

    López-Gutiérrez, J. M.; Gómez-Guzmán, J. M.; Chamizo, E.; Peruchena, J. I.; García-León, M.

    2013-01-01

    Radioactive residues, in order to be classified as Low-Level Waste (LLW), need to fulfil certain conditions; the limitation of the maximum activity from long-lived radionuclides is one of these requirements. In order to verify compliance to this limitation, the abundance of these radionuclides in the residue must be determined. However, performing this determination through radiometric methods constitutes a laborious task. In this work, 129I concentrations, 239+240Pu activities, and 240Pu/239Pu ratios are determined in low-level radioactive residues, including resins and dry sludge, from nuclear power plants in Spain. The use of Accelerator Mass Spectrometry (AMS) enables high sensitivities to be achieved, and hence these magnitudes can be re determined with good precision. Results present a high dispersion between the 129I and 239+240Pu activities found in various aliquots of the same sample, which suggests the existence of a mixture of resins with a variety of histories in the same container. As a conclusion, it is shown that activities and isotopic ratios can provide information on the processes that occur in power plants throughout the history of the residues. Furthermore, wipes from the monitoring of surface contamination of the José Cabrera decommissioning process have been analyzed for 129I determination. The wide range of measured activities indicates an effective dispersal of 129I throughout the various locations within a nuclear power plant. Not only could these measurements be employed in the contamination monitoring of the decommissioning process, but also in the modelling of the presence of other iodine isotopes.

  11. The efficacy of denaturing actinide elements as a means of decreasing materials attractiveness

    Energy Technology Data Exchange (ETDEWEB)

    Hase, K.R.; Bathke, C.G. [Los Alamos National Laboratory: P.O. Box 1663, Los Alamos, NM 87545 (United States); Ebbinghaus, B.B.; Sleaford, B.W.; Robel, M. [Lawrence Livermore National Laboratory: P.O. Box 808, Livermore, CA 94551 (United States); Collins, B.A.; Prichard, A.W. [Pacific Northwest National Laboratory: P.O. Box 999, Richland, WA 99352 (United States)

    2013-07-01

    This study considers the concept of denaturing as applied to the actinide elements present in spent fuel as a means to reduce materials attractiveness. Highly attractive materials generally have low values of bare critical mass, heat content, and dose. To denature an attractive element, its spent-fuel isotopic composition (isotopic vector) is intentionally modified by introducing sufficient quantities of a significantly less attractive isotope to dilute the concentration of a highly attractive isotope so that the overall attractiveness of the element is reduced. The authors used FOM (Figure of Merit) formula as the material attractiveness metric for their parametric determination of the attractiveness of the Pu and U. Materials attractiveness needs to be considered in three distinct phases in the process to construct a nuclear explosive device (NED): the acquisition phase, processing phase, and utilization phase. The results show that denaturing uranium with {sup 238}U is actually an effective means of reducing the attractiveness. For uranium with a large minority of {sup 235}U, a mixture of 80% {sup 238}U to 20% {sup 235}U is required to reduce the attractiveness to low. For uranium with a large concentration of {sup 233}U, a mixture of 88% {sup 238}U to 12% {sup 233}U is required to reduce the attractiveness to low. The results also show that denaturing plutonium with {sup 238}Pu is less effective than denaturing uranium with {sup 238}U. Using {sup 238}Pu as the denaturing agent would require 80% or more by mass in order to reduce the attractiveness to low. No amount of {sup 240}Pu is enough to reduce the plutonium attractiveness below medium. The combination of {sup 238}Pu and {sup 240}Pu would require approximately 70% {sup 238}Pu and 25% {sup 240}Pu by mass to reduce the plutonium attractiveness to low.

  12. Effects of nuclear data library and ultra-fine group calculation for large size sodium-cooled fast reactor OECD benchmarks

    International Nuclear Information System (INIS)

    The present paper summarizes calculation results for an international benchmark proposed by the Sodium-cooled Fast Reactor core Feed-back and transient response (SFR-FT) under the framework of the Working Party on scientific issues of Reactor Systems (WPRS) of the Nuclear Energy Agency of the OECD. It focuses on the large size oxide-fueled SFR. Library effect for core performance characteristics and reactivity feedback coefficients is analyzed using sensitivity analysis. The effect of ultra-fine energy group calculation in effective cross section generation is also analyzed. The discrepancy is about 0.4% for a neutron multiplication factor by changing JENDL-4.0 with JEFF-3.1. That is about -0.1% by changing JENDL-4.0 with ENDF/B-VII.1. The main contributions to the discrepancy between JENDL-4.0 and ENDF/B-VII.1 are 240Pu capture, 238U inelastic scattering and 239Pu fission. Those to the discrepancy between JENDL-4.0 and JEFF-3.1 are 23Na inelastic scattering, 56Fe inelastic scattering, 238Pu fission, 240Pu capture, 240Pu fission, 238U inelastic scattering, 239Pu fission and 239Pu nu-value. As for the sodium void reactivity, JEFF-3.1 and ENDF/B-VII.1 underestimate by about 8% compared with JENDL-4.0. The main contributions to the discrepancy between JENDL-4.0 and ENDF/B-VII.1 and 23Na elastic scattering, 23Na inelastic scattering and 239Pu fission. That to the discrepancy between JENDL-4.0 and JEFF-3.1 is 23Na inelastic scattering. The ultra-fine energy group calculation increases the sodium void reactivity by 2%. (author)

  13. Anthropogenic radionuclides in seawater in the East Sea/Japan Sea: Results of the first-stage Japanese-Korean-Russian expedition

    International Nuclear Information System (INIS)

    Measurements of anthropogenic radionuclides in seawater samples near dumping sites of the East Sea/Japan Sea were conducted, as the first-stage Japanese-Korean-Russian Joint Expedition, in March-April 1994, to assess radioactive contamination of the East Sea/Japan Sea after the dumping of radioactive wastes by the former Soviet Union and Russian Federation. Concentrations of 137Cs, 90Sr and 239,240Pu in surface waters of the East Sea/Japan Sea near dumping sites were in the ranges of 2.8-3.6,1.6-2.0, and 8-25 Bq kg-1, respectively. Surface 137Cs and 90Sr concentrations were the same order of magnitude as those observed in the North Pacific, whereas surface 239,240Pu concentration was significantly higher than those observed in the North Pacific. Vertical profiles of 137Cs and 90Sr, with surface maxima and decreasing with depth, showed higher depth gradients than those observed in the North Pacific, reflecting deep convection in the north central East Sea/Japan Sea. The higher 239,240Pu concentration in the surface waters of the north central East Sea/Japan Sea may reflect rapid recycling of deep Pu. The results revealed that most of the recent radioactivity observed in the north central East Sea/Japan Sea was of global fallout origin from atmospheric nuclear testing and partly the Chernobyl fallout. In this survey, there was no clear evidence of an increase in radionuclide concentrations due to the dumping of radioactive wastes by the former Soviet Union and Russian Federation. (Copyright (c) 1999 Elsevier Science B.V., Amsterdam. All rights reserved.)

  14. Short term soil erosion dynamics in alpine grasslands - Results from a Fallout Radionuclide repeated-sampling approach

    Science.gov (United States)

    Arata, Laura; Meusburger, Katrin; Zehringer, Markus; Ketterer, Michael E.; Mabit, Lionel; Alewell, Christine

    2016-04-01

    Improper land management and climate change has resulted in accelerated soil erosion rates in Alpine grasslands. To efficiently mitigate and control soil erosion and reduce its environmental impact in Alpine grasslands, reliable and validated methods for comprehensive data generation on its magnitude and spatial extent are mandatory. The use of conventional techniques (e.g. sediment traps, erosion pins or rainfall simulations) may be hindered by the extreme topographic and climatic conditions of the Alps. However, the application of the Fallout Radionuclides (FRNs) as soil tracers has already showed promising results in these specific agro-ecosystems. Once deposited on the ground, FRNs strongly bind to fine particles at the surface soil and move across the landscape primarily through physical processes. As such, they provide an effective track of soil and sediment redistribution. So far, applications of FRN in the Alps include 137Cs (half-life: 30.2 years) and 239+240Pu (239Pu [half-life = 24110 years] and 240Pu [half-life = 6561 years]). To investigate short term (4-5 years) erosion dynamics in the Swiss Alps, the authors applied a FRNs repeated sampling approach. Two study areas in the central Swiss Alps have been investigated: the Urseren Valley (Canton Uri), where significant land use changes occurred in the last centuries, and the Piora Valley (Canton Ticino), where land use change plays a minor role. Soil samples have been collected at potentially erosive sites along the valleys over a period of 4-5 years and measured for 137Cs and 239+240Pu activity. The inventory change between the sampling years indicates high erosion and deposition dynamics at both valleys. High spatial variability of 137Cs activities at all sites has been observed, reflecting the heterogeneous distribution of 137Cs fallout after the Chernobyl power plant accident in 1986. Finally, a new modelling technique to convert the inventory changes to quantitative estimates of soil erosion has

  15. Plutonium and americium in sediments of Lithuanian lakes

    International Nuclear Information System (INIS)

    The assessment of contribution of the global and the Chernobyl NPP (Nuclear Power Plant) accident plutonium and americium to plutonium pollution in sediments of Lithuanian lakes is presented. Theoretical evaluation of activity ratios of 238Pu/239+240Pu and 241Pu/239+240Pu in the reactor of unit 4 of the Chernobyl NPP before the accident was performed by means of the ORIGEN-ARP code from the SCALE 4.4A program package. Non-uniform distribution of radionuclides in depositions on the Lithuanian territory after nuclear weapon tests and the Chernobyl NPP accident is experimentally observed by measuring the lake sediment pollution with actinides. The activity concentration of sediments polluted with plutonium ranges from 2.0 ± 0.5 Bq/kg d.w. (dry weight) in Lake Asavelis to 14 ± 2 Bq/kg d.w. in Lake Juodis. The ratio of activity concentrations of plutonium isotopes 238Pu/239+240Pu measured by α-spectrometry in the 10-cm-thick upper layer of bottom sediment varies from 0.03 in Lake Juodis to 0.3 in Lake Zuvintas. The analysis of the ratio values shows that the deposition of the Chernobyl origin plutonium is prevailing in southern and south-western regions of Lithuania. Plutonium of nuclear weapon tests origin in sediments of lakes is observed on the whole territory of Lithuania, and it is especially distinct in central Lithuania. The americium activity due to 241Pu decay after the Chernobyl NPP accident and global depositions in bottom sediments of Lithuanian lakes has been evaluated to be from 0.9 to 5.7 Bq/kg. (author)

  16. Plutonium, cesium, uranium and thorium series radionuclides in the Hudson River estuary and other environments. Annual technical progress report, 1 December 1984-30 November 1985

    International Nuclear Information System (INIS)

    We have measured radionuclide activities in a large number of sediment cores and suspended particle samples throughout the salinity range of the Hudson River estuary. Activities of 137Cs, 134Cs and 60Co determined by gamma spectrometry and /sup 239,240/Pu and 238Pu determined by alpha spectrometry indicate reasonably rapid accumulation rates in the sediments of marginal cove areas, and very rapid deposition in the harbor region adjacent to New York City, resulting in /sup 239,240/Pu accumulations there more than an order of magnitude greater than the fallout delivery rate. Fallout /sup 239,240/Pu moving downstream in the Hudson appears to be almost completely retained within the system by particle deposition, while more than 50% of the 137Cs derived from both reactor releases and fallout has been exported from the tidal Hudson to coastal waters. Some significant movement of dissolved plutonium into the estuary from the adjacent coastal waters may well be occurring. Depth profiles of radionuclides in Hudson sediments do not appear to be significantly altered by physical mixing processes in the sediment in areas accumulating particles at greater than 1 cm/y. Transport of fallout radionuclides from the drainage basin to the tidal Hudson appears to have decreased much faster than would be calculated from continuous removal from a well-mixed soil reservoir, indicating that sequestering of a substantial portion of the soil fallout burden has occurred in the watershed soils over the past two decades. Activities of 60Co in New York harbor sediments in 1984 averaged considerably higher than in 1979 and 1981, suggesting releases of this nuclide to the Hudson comparable to the first five years of reactor operations. 12 figs., 9 tabs

  17. Chronology of Pu isotopes and 236U in an Arctic ice core.

    Science.gov (United States)

    Wendel, C C; Oughton, D H; Lind, O C; Skipperud, L; Fifield, L K; Isaksson, E; Tims, S G; Salbu, B

    2013-09-01

    In the present work, state of the art isotopic fingerprinting techniques are applied to an Arctic ice core in order to quantify deposition of U and Pu, and to identify possible tropospheric transport of debris from former Soviet Union test sites Semipalatinsk (Central Asia) and Novaya Zemlya (Arctic Ocean). An ice core chronology of (236)U, (239)Pu, and (240)Pu concentrations, and atom ratios, measured by accelerator mass spectrometry in a 28.6m deep ice core from the Austfonna glacier at Nordaustlandet, Svalbard is presented. The ice core chronology corresponds to the period 1949 to 1999. The main sources of Pu and (236)U contamination in the Arctic were the atmospheric nuclear detonations in the period 1945 to 1980, as global fallout, and tropospheric fallout from the former Soviet Union test sites Novaya Zemlya and Semipalatinsk. Activity concentrations of (239+240)Pu ranged from 0.008 to 0.254 mBq cm(-2) and (236)U from 0.0039 to 0.053 μBq cm(-2). Concentrations varied in concordance with (137)Cs concentrations in the same ice core. In contrast to previous published results, the concentrations of Pu and (236)U were found to be higher at depths corresponding to the pre-moratorium period (1949 to 1959) than to the post-moratorium period (1961 and 1962). The (240)Pu/(239)Pu ratio ranged from 0.15 to 0.19, and (236)U/(239)Pu ranged from 0.18 to 1.4. The Pu atom ratios ranged within the limits of global fallout in the most intensive period of nuclear atmospheric testing (1952 to 1962). To the best knowledge of the authors the present work is the first publication on biogeochemical cycles with respect to (236)U concentrations and (236)U/(239)Pu atom ratios in the Arctic and in ice cores.

  18. The effect of carbonate soil on transport and dose estimates for long-lived radionuclides at a U.S. Pacific test site

    Energy Technology Data Exchange (ETDEWEB)

    Conrado, C L; Hamilton, T F; Robison, W L; Stoker, A C

    1999-01-01

    The US conducted a series of nuclear tests from 1946 to 1958 at Bikini, a coral atoll, in the Marshall Islands (MI). The aquatic and terrestrial environments of the atoll are still contaminated with several long-lived radionuclides that were generated during testing. The four major radionuclides found in terrestrial plants and soils are Cesium-137 ({sup 137}Cs), Strontium-90 ({sup 90}Sr), Plutonium-239+240 ({sup 239+240}Pu) and Americium-241 ({sup 241}Am). {sup 137}Cs in the coral soils is more available for uptake by plants than {sup 137}Cs associated with continental soils of North America or Europe. Soil-to-plant {sup 137}Cs median concentration ratios (CR) (kBq kg{sup {minus}1} dry weight plant/kBq kg{sup {minus}1} dry weight soil) for tropical fruits and vegetables range between 0.8 and 36, much larger than the range of 0.005 to 0.5 reported for vegetation in temperate zones. Conversely, {sup 90}Sr median CRs range from 0.006 to 1.0 at the atoll versus a range from 0.02 to 3.0 for continental silica-based soils. Thus, the relative uptake of {sup 137}Cs and {sup 90}Sr by plants in carbonate soils is reversed from that observed in silica-based soils. The CRs for {sup 239+240}Pu and {sup 241}Am are very similar to those observed in continental soils. Values range from 10{sup {minus}6} to 10{sup {minus}4} for both {sup 239+240}Pu and {sup 241}Am. No significant difference is observed between the two in coral soil.

  19. Challenge in determination of long-lived radionuclides by ICP-MS

    International Nuclear Information System (INIS)

    The ultra-trace and isotope analysis of long-lived radionuclides in environmental materials (in biological or geological samples and waters) is relevant of increasing importance [1-5].E.g., the determination of long-lived radionuclides is for the detection of radionuclide contamination in environmental materials in which several radioactive nuclides (e.g.99Tc, 129I , 237Np, 239Pu, 240Pu, 241Am) are present from fallout due to nuclear weapons testing, nuclear power plants or nuclear accidents. Especially, isotope ratios of uranium and plutonium [6] can indicate the origin of contamination in the environmental samples

  20. The AS-76 interlaboratory experiment on the alpha spectrometric determination of Pu-238. Pt. 3

    International Nuclear Information System (INIS)

    Four plutonium samples containing 0.2, 0.8, 1.6 and 0.9 Atom% of 238Pu have been prepared for the Interlaboratory Experiment AS-76. Of these, three were input solutions from a reprocessing plant. The fourth sample was from a plutonium product solution. These samples have been characterized by two alpha spectrometry laboratories and two mass spectrometry laboratories to certify the ratio of alpha activities 238Pu/(239Pu + 240Pu) and the isotopic composition, respectively. (orig.) 891 HP/orig. 892 MKO

  1. Radiocaesium, plutonium and americium partitioning and solid speciation in sized, inter-tidal sediments from Strangford Lough

    International Nuclear Information System (INIS)

    Fine-grained surface (0-2 cm) sediment was collected at an inter-tidal site (Mahee Island) in Strangford Lough, on the NE coast of Ireland in September 1997. The sediment was wet-sieved into standard sized fractions using Endecott test sieves and the fractions assayed for 137Cs, 239,240Pu and 241Am content. Sub-samples of each fraction were measured with a Malvern 2600 laser diffraction analyser, which confirmed that >90% of the particles in each fraction was in the defined size range

  2. Environmental application of stable xenon and radioxenonmonitoring

    Energy Technology Data Exchange (ETDEWEB)

    Dresel, P. Evan; Olsen, Khris B.; Hayes, James C.; McIntyre,Justin I.; Waichler, Scott R.; Milbrath, Brian D.; Cooper, Matt; Kennedy,B. Mack

    2006-09-05

    Characterization of transuranic waste is needed to makedecisions about waste site remediation. Soil-gas sampling for xenonisotopes can be used to define the locations of spent fuel andtransuranic wastes. Radioxenon in the subsurface is characteristic oftransuranic waste and can be measured with extreme sensitivity usinglarge-volume soilgas samples. Measurements at the Hanford Site showed133Xe and 135Xe levels indicative of 240Pu spontaneous fission. Stablexenon isotopic ratios from fission are distinct from atmospheric xenonbackground. Neutron capture by 135Xe produces an excess of 136Xe inreactor-produced xenon providing a means of distinguishing spent fuelfrom separated transuranic materials.

  3. Pu isotopes in the western North Pacific Ocean before the accident at Fukushima Dai-ichi Nuclear Power Station

    Science.gov (United States)

    Yamada, M.; Zheng, J.; Aono, T.

    2011-12-01

    Anthropogenic radionuclides such as Pu-239 (half-life: 24100 yr), Pu-240 (half-life: 6560 yr) and Pu-241 (half-life: 14.325 yr) mainly have been released into the environment as the result of atmospheric nuclear weapons testing. In the North Pacific Ocean, two distinct sources of Pu isotopes can be identified; i.e., the global stratospheric fallout and close-in tropospheric fallout from nuclear weapons testing at the Pacific Proving Grounds in the Marshall Islands. The atom ratio of Pu-240/Pu-239 is a powerful fingerprint to identify the sources of Pu in the ocean. The Pu-240/Pu-239 atom ratios in seawater and marine sediment samples collected in the western North Pacific before the accident at Fukushima Dai-ichi Nuclear Power Station will provide useful background data for understanding the process controlling Pu transport and for distinguishing future Pu sources. The atom ratios of Pu-240/Pu-239 in water columns from the Yamato and Tsushima Basins in the Japan Sea were significantly higher than the mean global fallout ratio of 0.18; however, there were no temporal variation of atom ratios during the period from 1984 to 1993 in the Japan Sea. The total Pu-239+240 inventories in the whole water columns were approximately doubled during the period from 1984 to 1993 in the two basins. The atom ratio of Pu-240/Pu-239 in surface water from Sagami Bay, western North Pacific Ocean, was 0.224 and showed no notable variation from the surface to the bottom with the mean atom ratio being 0.234. The atom ratios for the Pacific coast, near the Rokkasho nuclear fuel reprocessing plant, were approximately the same as the 0.224 ratio obtained from Sagami Bay, western North Pacific margin. The atom ratios in the surficial sediments from Sagami Bay ranged from 0.229 to 0.247. The mean atom ratio in the sediment columns in the East China Sea ranged from 0.248 for the Changjiang estuary to 0.268 for the shelf edge. The observed atom ratios were significantly higher than the mean

  4. Distribution of Natural Radioactivity, 137Cs, 90Sr, and Plutonium Isotopes in a Water Column and Sediment Core along the Algerian Coast

    OpenAIRE

    Noureddine, A; M. BENKRID; R. Maoui; Menacer, M.; R. BOUDJENOUN

    2007-01-01

    Concentrations of natural (40K, 210Pb, uranium, and thorium series) and artificial radioelements (137Cs, 90Sr, 239+240Pu) were determined in seawater and sediment samples collected from stations along the Algerian coast. Seawater was collected from the surface to a maximum depth of 2000 m; the sediment cores were sampled from a depth of around 1500 m. This work was carried out in August 2001, in the framework of the Regional African project /7/004 (RAF), by the accomplishment of an oceanogra...

  5. Pu isotopes and {sup 241}Am activities determination in the evaluation of radiochemical sequential analyzes methodology for evaporator concentrate samples using alpha spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Reis Junior, Aluisio S.; Temba, Eliane S.C.; Kastner, Geraldo F.; Monteiro, Roberto P.G., E-mail: reisas@cdtn.br [Centro de Desenvolvimento da Tecnologia Nuclear (SERTA/CDTN/CNEN-MG), Belo Horizonte, MG (Brazil). Servico do Reator e Tecnicas Analiticas

    2015-07-01

    Alpha spectrometry analyzes were used for activity determinations of Pu and Am isotopes in evaporator concentrate samples from nuclear power plants. In this work it was used tracers for isotopes determination and quantification. The radiometric yields ranged from 60% to 100% and the Lower Limit of Detection was estimated as being 2.05 mBqKg{sup -1}. The relative standard deviations for replicate analysis were calculated for {sup 241}Am, 15.13% (sample J) and 9.38% (sample N), and for {sup 239+240}Pu, 8.16% (sample J) and 7.95% (sample N). (author)

  6. Plutonium isotopes in the ocean off Japan after Fukushima

    Energy Technology Data Exchange (ETDEWEB)

    Buesseler, K.; Black, E.; Pike, S. [Woods Hole Oceanographic Institution (United States); Kenna, T. [Lamont-Doherty Earth Observatory (United States); Masque, P. [Universitat Autonoma de Barcelona (Spain)

    2014-07-01

    The Fukushima Dai-ichi nuclear power plants (NPPs) are known to be an unprecedented accidental source of {sup 137}Cs, {sup 134}Cs and other volatile radionuclides to the ocean. Much less is known however about the extent of input of refractory radionuclides such as plutonium to the environment. Limited available data from land soils and vegetation, suggest at least some atmospheric delivery of particulate Pu but at very low levels relative to pre-existing fallout sources. To resolve Fukushima derived Pu from weapons testing derived Pu, information regarding the Pu isotopic composition is needed. The {sup 240}Pu/{sup 239}Pu atom ratio determined by mass spectrometric techniques, and the {sup 238}Pu/{sup 239,240}Pu activity ratio as measured by alpha counting are diagnostic with respect to Pu source. We review and present new data on the Pu isotopic ratios and concentrations in the oceans, combining several data sets on dissolved (from bottle sampling), suspended particulates (from filtration), sinking particles (from sediment traps) and seafloor sediments (from cores) to look for the Fukushima Pu signal. In most samples, the {sup 240}Pu/{sup 239}Pu ratios are in the range of 0.20-0.23, characteristic of Pu ocean signal which is a combination of global fallout with a characteristic ratio of 0.18 and local fallout from the Pacific Proving Grounds with ratios higher than 0.24, and known from prior studies to influence the ocean off Japan. In 2011, in surface ocean waters, we found ratios {sup 240}Pu/{sup 239}Pu >0.3, which implies a component of Fukushima Pu had been delivered to the ocean, given NPP derived end-member ratios of 0.35-0.45. Fukushima derived Pu was not found deeper in the water column or even at all stations, consistent with its rapid removal from the ocean and the high background of pre-existing Pu in the waters and sediments, masking the new Fukushima sources. With this data a mass balance will be made between Pu from global fallout, local fallout and

  7. Further results in search for transuranium elements in effluents discharged to air from nuclear power plants

    OpenAIRE

    Hölgye, Z.; Schlesingerová, E.

    2010-01-01

    In this work we present data on transuranium nuclides 238Pu, 239,240Pu, 241Am, 242Cm and 244Cm in effluents discharged to air (activity concentrations and annually discharged activities of individual radionuclides) from 7 stacks in 2004–2009. In the effluents discharged to air from one stack low activities of transuranium nuclides were observed throughout the studied period. Transuranium nuclides had been discharged to air from this stack also in previous years since 1996 when defect in the c...

  8. Intercomparison of radionuclide measurements in marine sediment sample IAEA-367

    International Nuclear Information System (INIS)

    The results of an intercomparison exercise on a Pacific Ocean sediment sample, IAEA-367, designed for the determination of artificial and natural radionuclides levels, are reported. The data from 81 laboratories representing 37 countries have been evaluated. The following are the recommended values, with confidence intervals, for 60Co, 90Sr, 137Cs, 239+240Pu (Reference date: 1 January 1990). Information values for 155Eu, 238Pu, 241Am, and 241Pu are reported. Information values for the following natural radionuclides 40K, 226Ra, 228Th, 230Th, 234U, 235U and 238U are also reported. (author)

  9. Intercomparison of radionuclide measurements in marine sediment sample IAEA-368

    International Nuclear Information System (INIS)

    The results of an intercomparison exercise on a Pacific Ocean sediment sample, IAEA-368, designed for the determination of artificial and natural radionuclides levels, are reported. The data from 89 laboratories representing 37 countries have been evaluated. The following are the recommended values, with confidence intervals, for 60Co, 155Eu, 2107Pb, 226Ra, 238U, 238Pu and239+240Pu (Reference date: 1 January 1990). Information values for 40K, 90Sr, 137Cs, 228Th, 230Th, 232Th, 234U, 235U and 241Am are also reported. (author)

  10. Plutonium source isotopic analysis with up to 25 mm Pb shielding using the FRAM Isotopic Analysis Code.

    Energy Technology Data Exchange (ETDEWEB)

    Hypes, Philip A.

    2000-01-01

    The FRAM Isotopics Analysis Code has been used to analyze plutonium spectra taken through very thick shielding. Three plutonium sources with 240Pu content of 6.6%, 9.7%, and 16.3% were measured with lead shielding thicknesses ranging from zero to 25.3 mm, in nominal increments of 1.6mm. Multiple spectra were taken for each sample at each shielding level, and the spectra were analyzed using FRAM V3.2. A new parameter set was developed to analyze spectra from zero to 25 mm lead. We will report on the accuracy capabilities of this parameter set.

  11. Dependence of Fission-Fragment Properties On Excitation Energy For Neutron-Rich Actinides

    Directory of Open Access Journals (Sweden)

    Ramos D.

    2016-01-01

    Isotopic fission yields of 250Cf, 244Cm, 240Pu, 239Np and 238U are presented in this work. With this information, the average number of neutrons as a function of the atomic number of the fragments is calculated, which reflects the impact of nuclear structure around Z=50, N=80 on the production of fission fragments. The characteristics of the Super Long, Standard I, Standard II, and Standard III fission channels were extracted from fits of the fragment yields for different ranges of excitation energy. The position and contribution of the fission channels as function of excitation energy are presented.

  12. A survey of radioactive fallout data in Alaska

    International Nuclear Information System (INIS)

    Considerable attention has been directed by the scientific community to assessing the levels and fate of radionuclides in Arctic ecosystems. The following text and tables present available data and discussion of radionuclide fallout in Alaska. A literature search of 23 on-line databases (Table 1) using Alaska, Strontium (Sr), Cesium (Cs), Plutonium (Pu) and Radionuclide as constraint terms responded with 177 possible citations. After eliminating duplicate citations, 31 articles were available: 17 were relevant to the subject matter; the remainder addressed geologic issues. All of the cited literature addressed 137Cs, 90Sr and 239,240Pu as a result of radionuclide fallout from nuclear testing or accidental release

  13. Environmental radioactivity in Greenland in 1981

    International Nuclear Information System (INIS)

    Measurements of fallout radioactivity in Greenland in 1981 are reported. Strontium-90 (and Cesium-137 in most cases) was determined in samples of precipitation, sea water, vegetation, animals, and drinking water. Estimates are given of the mean contents of 90Sr and 137Cs in the human diet in Greenland in 1981. Further results of the 239,240Pu and 241Am measurements on samples from the expedition to Thule in August 1979 are prsented. Brown algae collected in East Greenland in 1969 were analysed for Pu and Am. (author)

  14. Environmental radioactivity in Greenland in 1980

    International Nuclear Information System (INIS)

    Measurements of fallout radioactivity in Greenland in 1980 are reported. Strontium-90 (and Cesium-137 in most cases) was determined in samples of precipitation, sea water, vegetation, animals, and drinking water. Estimates are given of the mean contents of 90Sr and 137Cs in the human diet in Greenland in 1980. Provisional results of the 239Pu, 240Pu and 241Am measurements on samples from the expedition to Thule in August 1979 and from the Swedish YMER expedition in 1980 are presented. (author)

  15. Behaviour of long-lived radionuclides associated with deep-sea disposal of radioactive wastes

    International Nuclear Information System (INIS)

    The IAEA sponsored this Coordinated Research Programme to improve knowledge of various long-lived radionuclides likely to be dumped in the deep sea. During the three years of this programme the state of knowledge has advanced significantly in this area, and this document provides a review of the progress. The isotopes studied were mainly 238Pu, 239Pu, 240Pu, 241Am, 226Ra, 210Po, 90Sr, 137Cs, 60Co, and 99Tc. A separate abstract was prepared for each of the 15 papers

  16. Migration of plutonium isotopes in forest soil profiles in Lublin region (Eastern Poland)

    International Nuclear Information System (INIS)

    The distribution of Pu isotopes in three profiles of forest soil in Lublin region was determined. The retention half-time and migration velocity of 239,240Pu originated from global and Chernobyl fallouts was calculated. The average rate of migration of the global fallout plutonium was 0.4 cm/year and that of the Chernobyl one 0.7 cm/year. Good correlation between Pu concentration and organic matter contents was found only in the case of podzolic soil profile. In two profiles a good negative correlation between Pu activity and exchangeable pH of the soil layer was determined. (author)

  17. Plutonium emission from the Fukushima accident

    Energy Technology Data Exchange (ETDEWEB)

    Bossew, P., E-mail: pbossew@bfs.de [German Federal Office for Radiation Protection, Berlin (Germany)

    2013-07-01

    A strong earthquake and subsequent tsunami on 11{sup th} March 2011 initiated a severe accident in units 1 to 4 of Fukushima Dai-ichi nuclear power plant, resulting in substantial releases of radionuclides. While much has since been published 00 environmental contamination and exposure to radio--iodine and radio-caesium, little is known about releases of plutonium and other non-volatile elements. Although the total activities of released {sup 131}I, {sup 134}Cs and {sup 137}Cs are of the same order of magnitude as of the Chernobyl accident in 1986, the contribution of little volatile elements, including Pu, is much smaller in Fukushima fallout. The reason is the different physical nature of the accident sequence which led to a release of some 10{sup -}5% of the core inventories only (to be compared with 3.5% from Chernobyl). In this contribution the available data on Pu in Fukushima fallout will be reviewed. Data sources are mainly reports and press releases by Japanese authorities and a few scientific articles. The mean ratio {sup 239+240}Pu: {sup 137}Cs in the near field around the NPP (mainly part of Fukushima prefecture and districts of adjacent prefectures) can be assumed about 3 x 10{sup -}7{sup ,} to be compared to nearly 0.01 in the vicinity of Chernobyl, down to about 3 x 10 {sup -6} in Central Europe. Isotopic ratios {sup 238}Pu: {sup 239+240} Pu are about 2.2 (0.46 and 0.035 in Chemobyl and global fallout, respectively). Activity concentrations of Fukushima- {sup 239+240} Pu in surface soil were found up to above 0.1 Bq/kg d.m. in the immediate vicinity of the Fukushima NPP and about one order of magnitude less in Fukushima city, about 60 km away. The {sup 239+240} Pu activity released into the atmosphere is roughly estimated some 10{sup 9} Bq (Chemobyl : almost 10{sup 14} Bq). (author)

  18. Collective excited states in even–even nuclei with quadrupole and octupole deformations

    International Nuclear Information System (INIS)

    Deformed even–even nuclei with quadrupole and octupole deformations are investigated on the basis of a nonadiabatical collective model. It is shown that the model satisfactorily describes energy levels of the yrast and first nonyrast bands with alternating parity in the rare-earth nuclei 150Nd, 152,154Sm, 154Gd, 156Dy, 162,164Er and the actinides 232,234,236,238U. In the nuclei 156,158Gd, 224Ra, 228Th and 240Pu the energy levels of second nonyrast bands are also described. The structure of the considered alternating-parity bands is examined in terms of odd–even staggering diagrams. (author)

  19. Alternating-parity collective states of yrast and nonyrast bands in lanthanide and actinide nuclei

    International Nuclear Information System (INIS)

    Excited collective states of even-even nuclei featuring quadrupole and octupole deformations are studied within a nonadiabatic collective model with a Gaussian potential energy. Rotational states of the yrast band and vibrational-rotational states of nonyrast bands are considered in detail. The energies of alternating-parity excited states of the yrast band in the 164Er, 220Ra, and 224Th nuclei; the yrast and first nonyrast bands in the 154Sm and 160Gd nuclei; and the yrast, first nonyrast, and second nonyrast bands in the 224Ra and 240Pu nuclei are described well on the basis of the proposed model

  20. Plants as bio-monitors for Cs-137, Pu-238, Pu-239,240 and K-40 at the Savannah River Site.

    Science.gov (United States)

    Caldwell, Eric Frank; Duff, Martine C; Ferguson, Caitlin E; Coughlin, Daniel P

    2011-05-01

    The Savannah River Site was constructed in South Carolina to produce plutonium (Pu) in the 1950s. Discharges associated with these now-ceased operations have contaminated large areas within the site, particularly streams associated with reactor cooling basins. Evaluating the exposure risk of contamination to an ecosystem requires methodologies that can assess the bioavailability of contaminants. Plants, as primary producers, represent an important mode of transfer of contaminants from soils and sediments into the food chain. The objective of this study was to identify local area plants for their ability to act as bio-monitors of radionuclides. The concentrations of cesium-137 ((137)Cs), potassium-40 ((40)K), (238)Pu and (239,240)Pu in plants and their associated soils were determined using γ and α spectrometry. The ratio of contamination concentration found in the plant relative to the soil was calculated to assess a concentration ratio (CR). The highest CR for (137)Cs was found in Pinus palustris needles (CR of 2.18). The correlation of soil and plant (137)Cs concentration was strong (0.76) and the R(2) (0.58) from the regression was significant (p = 0.006). This suggests the ability to predict the degree of (137)Cs contamination of a soil through analysis of the pine needles. The (238)Pu and (239,240)Pu concentrations were most elevated within the plant roots. Extremely high CR values were found in Sparganium americanum (bur-reed) roots with a value of 5.86 for (238)Pu and 5.66 for (239,240)Pu. The concentration of (40)K was measured as a known congener of (137)C. Comparing (40)K and (137)C concentrations in each plant revealed an inverse relationship for these radioisotopes. Correlating (40)K and (137)Cs was most effective in identifying plants that have a high affinity for (137)Cs uptake. The P. palustris and S. americanum proved to be particularly strong accumulators of all K congeners from the soil. Some species that were measured, warrant further

  1. Shapes and Dynamics from the Time-Dependent Mean Field

    CERN Document Server

    Stevenson, P D; Rios, A

    2015-01-01

    Explaining observed properties in terms of underlying shape degrees of freedom is a well--established prism with which to understand atomic nuclei. Self--consistent mean--field models provide one tool to understand nuclear shapes, and their link to other nuclear properties and observables. We present examples of how the time--dependent extension of the mean--field approach can be used in particular to shed light on nuclear shape properties, particularly looking at the giant resonances built on deformed nuclear ground states, and at dynamics in highly-deformed fission isomers. Example calculations are shown of $^{28}$Si in the first case, and $^{240}$Pu in the latter case.

  2. Radionuclide Concentrations in Honey Bees from Area G at TA-54 during 1998

    Energy Technology Data Exchange (ETDEWEB)

    Haarmann, T.K.; Fresquez, P.R.

    1999-06-01

    Honey bees were collected from two colonies located at Los Alamos National Laboratory's Area G, Technical Area 54, and from one control (background) colony located near Jemez Springs, NM. Samples were analyzed for various radionuclides. Area G sample results from both colonies were higher than the upper (95%) level background concentration for {sup 239,240}Pu, {sup 3}H, and total uranium. Sample results from one colony were higher than the upper (95%) level background concentration for {sup 238}Pu.

  3. Variable dead time counters: 2. A computer simulation

    International Nuclear Information System (INIS)

    A computer model has been developed to give a pulse train which simulates that generated by a variable dead time counter (VDC) used in safeguards determination of Pu mass. The model is applied to two algorithms generally used for VDC analysis. It is used to determine their limitations at high counting rates and to investigate the effects of random neutrons from (α,n) reactions. Both algorithms are found to be deficient for use with masses of 240Pu greater than 100g and one commonly used algorithm is shown, by use of the model and also by theory, to yield a result which is dependent on the random neutron intensity. (author)

  4. Evaluation and calculation of neutron transactinide cross-sections

    International Nuclear Information System (INIS)

    This paper reviews the state of the art of nuclear theory and its application to the evaluation and calculation of neutron reaction cross sections of transactinium isotopes. In particular, the paper describes the current evaluation of the total files of neutron reaction data for 240Pu and 241Pu in the energy range between 10-5 eV and 15 MeV based on a thorough analysis of available experimental data and on the use of modern theoretical concepts, and the work in progress on the evaluation of the total neutron reaction data file for 242Pu and 241Am. (author)

  5. Effect of carbonate soil on transport and dose estimates from long-lived radionuclides at U. S. Pacific Test Site

    Energy Technology Data Exchange (ETDEWEB)

    Conrado, C.L.; Hamilton, T.F.; Robison, W.L.; Stoker, A.C.

    1998-09-01

    The United States conducted a series of nuclear tests from 1946 to 1958 at Bikini, a coral atoll, in the Marshall Islands (MI). The aquatic and terrestrial environments of the atoll are still contaminated with several long-lived radionuclides that were generated during testing. The four major radionuclides found in terrestrial plants and soils are Cesium-137 ({sup 137} Cs), Strontium-90 ({sup 90} Sr), Plutonium-239+ 240 ({sup 239+240}Pu) and Americium-241 ({sup 241}Am). {sup 137}Cs in the coral soils is more available for uptake by plants than {sup 137}Cs associated with continental soils of North America or Europe. Soil-to-plant {sup 137}Cs median concentration ratios (CR) (kBq kg{sup {minus}1} dry weight plant/kBq kg {sup {minus}1} dry weight soil) for tropical fruits and vegetables range between 0.8 and 36, much larger than the range of 0.005 to 0.5 reported for vegetation in temperate zones. Conversely, {sup 90}Sr median CRs range from 0.006 to 1.0 at the atoll versus a range from 0.02 to 3.0 for continental silica-based soils. Thus, the relative uptake of {sup 137}Cs and {sup 90}Sr by plants in carbonate soils is reversed from that observed in silica-based soils. The CRs for {sup 239+240}Pu and {sup 241}Am are very similar to those observed in continental soils. Values range from 10{sup {minus}6} to 10{sup {minus}4} for both {sup 239+240}Pu and {sup 241}Am. No significant difference is observed between the two in coral soil. The uptake of {sup 137}Cs by plants is enhanced because of the absence of mineral binding sites and the low concentration of potassium in the coral soil. {sup 137}Cs is bound to the organic fraction of the soil, whereas {sup 90}Sr, {sup 239+240}Pu and {sup 241}Am are primarily bound to soil particles. Assessment of plant uptake for {sup 137}Cs and {sup 90}Sr into locally grown food crops was a major contributing factor in (1) reliably predicting the radiological dose for returning residents, and (2) developing a strategy to limit the

  6. Vertical distribution of (241)Pu in the southern Baltic Sea sediments.

    Science.gov (United States)

    Strumińska-Parulska, Dagmara I

    2014-12-15

    The vertical distribution of plutonium (241)Pu in marine sediments can assist in determining the deposition history and sedimentation process of analyzed regions. In addition, (241)Pu/(239+240)Pu activity ratio could be used as a sensitive fingerprint for radioactive source identification. The present preliminary studies on vertical distribution of (241)Pu in sediments from four regions of the southern Baltic Sea are presented. The distribution of (241)Pu was not uniform and depended on sediment geomorphology and depth as well as location. The highest concentrations of plutonium were found in the surface layers of all analyzed sediments and originated from the Chernobyl accident.

  7. Long-range tropospheric transport of uranium and plutonium weapons fallout from Semipalatinsk nuclear test site to Norway.

    Science.gov (United States)

    Wendel, Cato Christian; Fifield, L Keith; Oughton, Deborah H; Lind, Ole Christian; Skipperud, Lindis; Bartnicki, Jerzy; Tims, Stephen G; Høibråten, Steinar; Salbu, Brit

    2013-09-01

    A combination of state-of-the-art isotopic fingerprinting techniques and atmospheric transport modelling using real-time historical meteorological data has been used to demonstrate direct tropospheric transport of radioactive debris from specific nuclear detonations at the Semipalatinsk test site in Kazakhstan to Norway via large areas of Europe. A selection of archived air filters collected at ground level at 9 stations in Norway during the most intensive atmospheric nuclear weapon testing periods (1957-1958 and 1961-1962) has been screened for radioactive particles and analysed with respect to the concentrations and atom ratios of plutonium (Pu) and uranium (U) using accelerator mass spectrometry (AMS). Digital autoradiography screening demonstrated the presence of radioactive particles in the filters. Concentrations of (236)U (0.17-23nBqm(-3)) and (239+240)Pu (1.3-782μBqm(-3)) as well as the atom ratios (240)Pu/(239)Pu (0.0517-0.237) and (236)U/(239)Pu (0.0188-0.7) varied widely indicating several different sources. Filter samples from autumn and winter tended to have lower atom ratios than those sampled in spring and summer, and this likely reflects a tropospheric influence in months with little stratospheric fallout. Very high (236)U, (239+240)Pu and gross beta activity concentrations as well as low (240)Pu/(239)Pu (0.0517-0.077), (241)Pu/(239)Pu (0.00025-0.00062) and (236)U/(239)Pu (0.0188-0.046) atom ratios, characteristic of close-in and tropospheric fallout, were observed in filters collected at all stations in Nov 1962, 7-12days after three low-yield detonations at Semipalatinsk (Kazakhstan). Atmospheric transport modelling (NOAA HYSPLIT_4) using real-time meteorological data confirmed that long range transport of radionuclides, and possibly radioactive particles, from Semipalatinsk to Norway during this period was plausible. The present work shows that direct tropospheric transport of fallout from atmospheric nuclear detonations periodically may have

  8. Plutonium as a tracer for soil erosion assessment in northeast China

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Yihong [School of Geographic and Oceanographic Sciences, Nanjing University, Nanjing 210023 (China); Qiao, Jixin [Center for Nuclear Technologies, Technical University of Denmark, Risø Campus, DK-4000 Roskilde (Denmark); Pan, Shaoming, E-mail: span@nju.edu.cn [School of Geographic and Oceanographic Sciences, Nanjing University, Nanjing 210023 (China); Hou, Xiaolin, E-mail: xiho@dtu.dk [Center for Nuclear Technologies, Technical University of Denmark, Risø Campus, DK-4000 Roskilde (Denmark); Xi' an AMS Center, SKLLQG, Institute of Earth Environment, CAS, Xi' an 710075 (China); Roos, Per [Center for Nuclear Technologies, Technical University of Denmark, Risø Campus, DK-4000 Roskilde (Denmark); Cao, Liguo [School of Geographic and Oceanographic Sciences, Nanjing University, Nanjing 210023 (China)

    2015-04-01

    Soil erosion is one of the most serious environmental and agricultural problems faced by human society. Assessing intensity is an important issue for controlling soil erosion and improving eco-environmental quality. The suitability of the application of plutonium (Pu) as a tracer for soil erosion assessment in northeast China was investigated by comparing with that of {sup 137}Cs. Here we build on preliminary work, in which we investigated the potential of Pu as a soil erosion tracer by sampling additional reference sites and potential erosive sites, along the Liaodong Bay region in northeast China, for Pu isotopes and {sup 137}Cs. {sup 240}Pu/{sup 239}Pu atomic ratios in all samples were approximately 0.18, which indicated that the dominant source of Pu was the global fallout. Pu showed very similar distribution patterns to those of {sup 137}Cs at both uncultivated and cultivated sites. {sup 239+240}Pu concentrations in all uncultivated soil cores followed an exponential decline with soil depth, whereas at cultivated sites, Pu was homogenously distributed in plow horizons. Factors such as planted crop types, as well as methods and frequencies of irrigation and tillage were suggested to influence the distribution of radionuclides in cultivated land. The baseline inventories of {sup 239+240}Pu and {sup 137}Cs were 88.4 and 1688 Bq m{sup −2} respectively. Soil erosion rates estimated by {sup 239+240}Pu tracing method were consistent with those obtained by the {sup 137}Cs method, confirming that Pu is an effective tracer with a similar tracing behavior to that of {sup 137}Cs for soil erosion assessment. - Highlights: • The potential for the use of Pu as a soil erosion tracer was investigated. • Pu would be a good tracer given its long half-life. • Depth profiles of Pu in soils were systematically studied and compared to {sup 137}Cs. • Pu is an effective soil erosion tracer with behavior similar to that of {sup 137}Cs. • Thus, Pu provides a means of

  9. Spallation Neutron Spectrum on a Massive Lead/Paraffin Target Irradiated with 1 GeV Protons

    CERN Document Server

    Adam, J; Barashenkov, V S; Brandt, R; Golovatiouk, V M; Kalinnikov, V G; Katovsky, K; Krivopustov, M I; Kumar, V; Kumawat, H; Odoj, R; Pronskikh, V S; Solnyshkin, A A; Stegailov, V I; Tsoupko-Sitnikov, V M; Westmeier, W

    2004-01-01

    The spectra of gamma-ray emitted by decaying residual nuclei, produced by spallation neutrons with (n, xn), (n,xnyp), (n,p), (n,gamma) reactions in activation threshold detectors - namely, ^{209}Bi, ^{197}Au, ^{59}Co, ^{115}In, ^{232}Th, were measured in the Laboratory of Nuclear Problems (LNP), JINR, Dubna, Russia. Spallation neutrons were generated by bombarding a 20 cm long cylindrical lead target, 8 cm in diameter, surrounded by a 6 cm thick layer of paraffin moderator, with a 1 GeV proton beam from the Nuclotron accelerator. Reaction rates and spallation neutron spectrum were measured and compared with CASCADE code calculations.

  10. Program DDCS for nucleon and composite particle DDX of nucleon induced reactions up to tens of MeV

    International Nuclear Information System (INIS)

    DDCS is a program for calculating the neutron or proton induced reactions of medium-heavy nuclei in the incident energy range up to 50 MeV including 5 emission processes. This program is written in FORTAN-77 on microscopic computer 486. DDCS is constructed within the framework of optical model, generalized master equation of the exciton model, and the evaporation model. The effect of recoil nucleus is considered in this program. DDCS has been used to calculate reactions of n + 56Fe, n + 93Nb, P + 120Sn, P + 197Au, and P + 209Bi. Pretty good results in agreement with the experimental data were obtained

  11. Low-energy fusion dynamics of weakly bound nuclei: A time dependent perspective

    Science.gov (United States)

    Diaz-Torres, A.; Boselli, M.

    2016-05-01

    Recent dynamical fusion models for weakly bound nuclei at low incident energies, based on a time-dependent perspective, are briefly presented. The main features of both the PLATYPUS model and a new quantum approach are highlighted. In contrast to existing timedependent quantum models, the present quantum approach separates the complete and incomplete fusion from the total fusion. Calculations performed within a toy model for 6Li + 209Bi at near-barrier energies show that converged excitation functions for total, complete and incomplete fusion can be determined with the time-dependent wavepacket dynamics.

  12. Systematics of fission cross sections at the intermediate energy region

    Energy Technology Data Exchange (ETDEWEB)

    Fukahori, Tokio; Chiba, Satoshi [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    1997-03-01

    The systematics was obtained with fitting experimental data for proton induced fission cross sections of Ag, {sup 181}Ta, {sup 197}Au, {sup 206,207,208}Pb, {sup 209}Bi, {sup 232}Th, {sup 233,235,238}U, {sup 237}Np and {sup 239}Pu above 20 MeV. The low energy cross section of actinoid nuclei is omitted from systematics study, since the cross section has a complicated shape and strongly depends on characteristic of nucleus. The fission cross sections calculated by the systematics are in good agreement with experimental data. (author)

  13. Studies of giant multipole resonances with intermediate energy heavy ions

    International Nuclear Information System (INIS)

    The role of intermediate energy heavy ions in the study of giant multipole resonances is explored, with emphasis on gamma decay coincidence experiments. Experiments on 208Pb bombarded by 22 MeV/nucleon and 84 MeV/nucleon 17O are discussed and compared. The role of Coulomb excitation in the 84 MeV/nucleon data is emphasized and some consequences for study of isovector resonance strength are explored. A comparison of the excitation and decay of the isovector giant dipole resonance in 208Pb and 209Bi excited with 84 MeV/nucleon 17O scattering is presented. 19 refs., 15 figs., 1 tab

  14. An empirical fit to estimated neutron emission cross sections from proton induced reactions

    Indian Academy of Sciences (India)

    Moumita Maiti; Maitreyee Nandy; S N Roy; P K Sarkar

    2003-01-01

    Neutron emission cross section for various elements from 9Be to 209Bi have been calculated using the hybrid model code ALICE-91 for proton induced reactions in the energy range 25 MeV to 105 MeV. An empirical expression relating neutron emission cross section to target mass number and incident proton energy has been obtained. The simple expression reduces the computation time significantly. The trend in the variation of neutron emission cross sections with respect to the target mass number and incident proton energy has been discussed within the framework of the model used.

  15. Nuclear physics research program at the 30 MeV Karaj cyclotron

    Energy Technology Data Exchange (ETDEWEB)

    Noshad, H. E-mail: hnoshad@seai.neda.net.ir; Soheyli, S.; Lamehi-Rachti, M.; Talebi-Taher, A.R.; Aslani, Gh.; Maboudi-Moghaddam, S.; Rahighi, J.; Kakuee, O.R.; Heydari, N

    2002-08-01

    A versatile reaction chamber and its accessories as well as a multiparameter data acquisition system were designed, assembled, and installed in the R and D hall at NRCAM to allow nuclear measurements. The {sup 209}Bi(p,f) and {sup 197}Au(p,f) reaction experiments at E{sub p}=30 MeV were performed. The good agreement between our experimental results as compared with previously published data are presented here to show the reliability of our apparatus. In the case of the bismuth reaction, the fission cross section obtained by using pair spectrometry as well as its associated error have been measured for the first time.

  16. Measurement of nuclear cross sections using radioactive beams; Medicion de secciones eficaces nucleares usando haces radiactivos

    Energy Technology Data Exchange (ETDEWEB)

    Lizcano, D.; Aguilera, E.F.; Martinez Q, E. [Instituto Nacional de Investigaciones Nucleares, A.P. 18-1027, 11801 Mexico D.F. (Mexico)

    2000-07-01

    One of the main applications of the production and use of nuclear radioactive beams is the measurement of nuclear cross sections. In this work is used a {sup 6} He nuclear radioactive beam ({beta} emitting with half life 806.7 ms) for the study of the reaction {sup 6} + {sup 209} Bi which could have several products. This investigation was realized in collaboration with the personnel of the Nuclear Structure laboratory at the University of Notre Dame (U.S.A.) and the National institute of Nuclear Research and CONACyT by Mexico. (Author)

  17. Nuclear Matter Incompressibility Effect on the Cross Section of Fusion Reactions with a weakly bound projectile

    CERN Document Server

    Seyyedi, S A

    2015-01-01

    Fusion reactions with a weakly bound projectile are studied using the double-folding model along with a repulsive interaction modifying term. Using this modified potential, including nuclear matter incompressibility effects, the fusion reaction cross sections and suppression parameters are calculated for 9Be +209Bi,208Pb,29Si and 27Al reactions. The results show that applying these effects at energies near the Coulomb barrier improves the agreement between the calculated and experimental cross sections, and modifies the mean values of the suppression parameter.

  18. Study of rare alpha decays with scintillating bolometers

    Energy Technology Data Exchange (ETDEWEB)

    Cardani, L., E-mail: laura.cardani@roma1.infn.it [Dipartimento di Fisica, Sapienza University of Roma, Roma I-00185 (Italy); INFN, Sezione di Roma, Roma I-00185 (Italy)

    2013-08-01

    Rare α decays can be studied with an unprecedented sensitivity by means of scintillating bolometers, as these detectors can provide a large source mass as well as an excellent resolution and can disentangle the nature of the interacting particle thanks to the different light yield. As an example of the results that can be obtained with this technique, I report the conclusive test on the identification of {sup 209}Bi decay and the measurement of the half-life of this isotope. In addition, I present a measurement with a PbWO{sub 4} scintillating bolometer, in which the lead isotopes decays were studied.

  19. Atlas of giant dipole resonances. Parameters and graphs of photonuclear reaction cross sections

    International Nuclear Information System (INIS)

    Parameters of giant dipole resonances (GDR) observed in photonuclear reaction cross sections using various beams of incident photons are presented. Data, given for 200 stable isotopes from 2H to 243Am including their natural compositions, were collected from papers published over the years 1951-1996. GDR parameters, such as energy positions, amplitudes and widths, are included into the table and organized by element, isotope and reaction. Graphs of the majority of the photonuclear reaction cross sections, included in the international nuclear data library EXFOR by the end of 1998, are presented. The graphs are provided for 182 stable isotopes and natural compositions. (author)

  20. Pulse pile-up and dead time corrections for digitized signals from a BaF{sub 2} calorimeter

    Energy Technology Data Exchange (ETDEWEB)

    Mendoza, E., E-mail: emilio.mendoza@ciemat.es [CIEMAT, Avda. Complutense 40, 28040 Madrid (Spain); Cano-Ott, D., E-mail: daniel.cano@ciemat.es [CIEMAT, Avda. Complutense 40, 28040 Madrid (Spain); Guerrero, C., E-mail: carlos.guerrero@cern.ch [CERN, Physics Department, Geneva (Switzerland); CIEMAT, Avda. Complutense 40, 28040 Madrid (Spain); Berthoumieux, E., E-mail: Eric.Berthoumieux@cea.fr [CEA/Saclay - IRFU, Gif-sur-Yvette (France); CERN, Physics Department, Geneva (Switzerland)

    2014-12-21

    The pulse pile-up and associated dead time effects in an {sup 243}Am(n,γ) cross section measurement with a BaF{sub 2} Total Absorption Calorimeter at the CERN n{sub T}OF facility have been characterized. In this case, reliable corrections of these effects are crucial because of the complex detector configuration and of the high count rate induced by the sample activity of 50 MBq. The techniques, which have been developed for offline processing of the present data, may be of general interest for the analysis of other experiments using digital acquisition systems.

  1. Pulse pile-up and dead time corrections for digitized signals from a BaF2 calorimeter

    Science.gov (United States)

    Mendoza, E.; Cano-Ott, D.; Guerrero, C.; Berthoumieux, E.

    2014-12-01

    The pulse pile-up and associated dead time effects in an 243Am(n,γ) cross section measurement with a BaF2 Total Absorption Calorimeter at the CERN n_TOF facility have been characterized. In this case, reliable corrections of these effects are crucial because of the complex detector configuration and of the high count rate induced by the sample activity of 50 MBq. The techniques, which have been developed for offline processing of the present data, may be of general interest for the analysis of other experiments using digital acquisition systems.

  2. Sequential determination of Pu and Am radioisotopes in environmental samples; a comparison of two separation procedures

    International Nuclear Information System (INIS)

    Two separation methods for the sequential determination of Am and Pu radionuclides are presented and the results obtained are compared. Analysis involves leaching the sample with concentrated nitric acid (HNO3), followed by radiochemical separation using extraction chromatographic resins (UTEVA, TRU) and anion exchange. Sources for alpha spectrometry were prepared by micro-precipitation on neodymium fluoride (NdF3). The chemical recoveries were determined using 242Pu and 243Am tracers. The methods were tested on reference materials and on two sediments. All the results were in good agreement with the reference values. The evaluation of uncertainty is also included

  3. Preparation of targets for nuclear chemistry experiments at DANCE

    International Nuclear Information System (INIS)

    In this paper, we describe the separation chemistry and electrodepositions conducted for the preparation of 241Am, 243Am and 233U targets used for cross-section measurements at DANCE. Thick, adherent deposits were prepared using molecular plating from isopropyl alcohol solutions. Improved yields and thicknesses were observed for 241Am electrodeposition after the material was purified using TRU resin from Eichrom. Similarly, 233U deposits were improved after purification with an anion exchange column in 9 M HBr followed by purification using UTEVA resin from Eichrom. (author)

  4. Spectroscopic Tools Applied to Element Z = 115 Decay Chains

    Directory of Open Access Journals (Sweden)

    Forsberg U.

    2014-03-01

    Full Text Available Nuclides that are considered to be isotopes of element Z = 115 were produced in the reaction 48Ca + 243Am at the GSI Helmholtzzentrum für Schwerionenforschung Darmstadt. The detector setup TASISpec was used. It was mounted behind the gas-filled separator TASCA. Thirty correlated α-decay chains were found, and the energies of the particles were determined with high precision. Two important spectroscopic aspects of the offline data analysis are discussed in detail: the handling of digitized preamplified signals from the silicon strip detectors, and the energy reconstruction of particles escaping to upstream detectors relying on pixel-by-pixel dead-layer thicknesses.

  5. Research of vertical migration of radionuclides in the soil at testing 'Red forest' area

    International Nuclear Information System (INIS)

    Researches of vertical migration of Chernobyl origin radionuclides at testing 'Red forest' rea in 5-km ChNPP-zone were carried out. The γ- and β- spectrometer measurements of soil samples were carried out using the anticompton spectrometer and a beta spectrometer. Presence of 60Co, 134, 137Cs, 154,155Eu, 241Am to depth of 30 cm in all soil cuts was fixed. The sites with sod-low-podzol sandy soils on alluvial sands contain 137Cs, 90Sr and 241Am to depth of 60 cm. The presence 243Am and 243Cm was found in the top layers of soils at territory of testing area.

  6. Spectroscopy of element 115 decay chains

    Energy Technology Data Exchange (ETDEWEB)

    Rudolph, Dirk [Lund University, Sweden; Forsberg, U. [Lund University, Sweden; Golubev, P. [Lund University, Sweden; Sarmiento, L. G. [Lund University, Sweden; Yakushev, A. [Gesellschaft fur Schwerionenforschung (GSI), Germany; Andersson, L.-L. [Johannes Gutenberg-Universitaet Mainz, Mainz, Germany; Di Nitto, A. [Johannes Gutenberg-Universitaet Mainz, Mainz, Germany; Duehllmann, Ch. E. [Gesellschaft fur Schwerionenforschung (GSI), Germany; Gates, J. M. [Lawrence Berkeley National Laboratory (LBNL); Gregorich, K. E. [Lawrence Berkeley National Laboratory (LBNL); Gross, Carl J [ORNL; Hessberger, F. P. [Gesellschaft fur Schwerionenforschung (GSI), Germany; Herzberg, R.-D [University of Liverpool; Khuyagbaatar, J. [Johannes Gutenberg-Universitaet Mainz, Mainz, Germany; Kratz, J. V. [Johannes Gutenberg-Universitaet Mainz, Mainz, Germany; Rykaczewski, Krzysztof Piotr [ORNL; Schaedel, M. [Gesellschaft fur Schwerionenforschung (GSI), Germany; Aberg, S. [Lund University, Sweden; Ackermann, D. [GSI-Hemholtzzentrum fur Schwerionenforschung, Darmstadt, Germany; Block, M. [Gesellschaft fur Schwerionenforschung (GSI), Germany; Brand, H. [Gesellschaft fur Schwerionenforschung (GSI), Germany; Carlsson, B. G. [Lund University, Sweden; Cox, D. [University of Liverpool; Derkx, X. [Johannes Gutenberg-Universitaet Mainz, Mainz, Germany; Eberhardt, K. [Johannes Gutenberg-Universitaet Mainz, Mainz, Germany; Even, J. [Johannes Gutenberg-Universitaet Mainz, Mainz, Germany; Fahlander, C. [Lund University, Sweden; Gerl, J. [Gesellschaft fur Schwerionenforschung (GSI), Germany; Jaeger, E. [Gesellschaft fur Schwerionenforschung (GSI), Germany; Kindler, B. [Gesellschaft fur Schwerionenforschung (GSI), Germany; Krier, J. [Gesellschaft fur Schwerionenforschung (GSI), Germany; Kojouharov, I. [Gesellschaft fur Schwerionenforschung (GSI), Germany; Kurz, N. [Gesellschaft fur Schwerionenforschung (GSI), Germany; Lommel, B. [Gesellschaft fur Schwerionenforschung (GSI), Germany; Mistry, A. [University of Liverpool; Mokry, C. [Johannes Gutenberg-Universitaet Mainz, Mainz, Germany; Nitsche, H. [Lawrence Berkeley National Laboratory (LBNL); Omtvedt, J. P. [Paul Scherrer Institut, Villigen, Switzerland; Papadakis, P. [University of Liverpool; Ragnarsson, I. [Lund University, Sweden; Runke, J. [Gesellschaft fur Schwerionenforschung (GSI), Germany; Schaffner, H. [Gesellschaft fur Schwerionenforschung (GSI), Germany; Schausten, B. [Gesellschaft fur Schwerionenforschung (GSI), Germany; Thoerle-Pospiech, P. [Johannes Gutenberg-Universitaet Mainz, Mainz, Germany; Torres, T. [Gesellschaft fur Schwerionenforschung (GSI), Germany; Traut, T. [Johannes Gutenberg-Universitaet Mainz, Mainz, Germany; Trautmann, N. [Johannes Gutenberg-Universitaet Mainz, Mainz, Germany; Tuerler, A. [Paul Scherrer Institut, Villigen, Switzerland; Ward, A. [University of Liverpool; Ward, D. E. [Lund University, Sweden; Wiehl, N. [Johannes Gutenberg-Universitaet Mainz, Mainz, Germany

    2013-01-01

    A high-resolution a, X-ray and -ray coincidence spectroscopy experiment was conducted at the GSI Helmholtzzentrum fu r Schwerionenforschung. Thirty correlated a-decay chains were detected following the fusion-evaporation reaction 48Ca + 243Am. The observations are consistent with previous assignments of similar decay chains to originate from element Z = 115. The data includes first candidates of fingerprinting the decay step Mt --> Bh with characteristic X rays. For the first time, precise spectroscopy allows the derivation of excitation schemes of isotopes along the decay chains starting with elements Z > 112. Comprehensive Monte-Carlo simulations accompany the data analysis. Nuclear structure models provide a first level interpretation.

  7. Rapid determination of 237Np in soil samples by multi-collector inductively-coupled plasma mass spectrometry and gamma spectrometry

    OpenAIRE

    Yi, Xiaowei; Shi, Yanmei; Xu, Jiang; He, Xiaobing; ZHANG, HAITAO; Lin, Jianfeng

    2013-01-01

    A radiochemical procedure is developed for the determination of 237Np in soil with multi-collector inductively-coupled plasma mass spectrometry (MC-ICP-MS) and gamma-spectrometry. 239Np (milked from 243Am) was used as an isotopic tracer for chemical yield determination. The neptunium in the soil is separated by thenoyl-trifluoracetone extraction from 1 M HNO3 solution after reducing Np to Np(IV) with ferrous sulfamate, and then purified with Dowex 1 × 2 anion exchange resin. 239Np in the resu...

  8. Northern Marshall Islands radiological survey: sampling and analysis summary

    Energy Technology Data Exchange (ETDEWEB)

    Robison, W.L.; Conrado, C.L.; Eagle, R.J.; Stuart, M.L.

    1981-07-23

    A radiological survey was conducted in the Northern Marshall Islands to document reamining external gamma exposures from nuclear tests conducted at Enewetak and Bikini Atolls. An additional program was later included to obtain terrestrial and marine samples for radiological dose assessment for current or potential atoll inhabitants. This report is the first of a series summarizing the results from the terrestrial and marine surveys. The sample collection and processing procedures and the general survey methodology are discussed; a summary of the collected samples and radionuclide analyses is presented. Over 5400 samples were collected from the 12 atolls and 2 islands and prepared for analysis including 3093 soil, 961 vegetation, 153 animal, 965 fish composite samples (average of 30 fish per sample), 101 clam, 50 lagoon water, 15 cistern water, 17 groundwater, and 85 lagoon sediment samples. A complete breakdown by sample type, atoll, and island is given here. The total number of analyses by radionuclide are 8840 for /sup 241/Am, 6569 for /sup 137/Cs, 4535 for /sup 239 +240/Pu, 4431 for /sup 90/Sr, 1146 for /sup 238/Pu, 269 for /sup 241/Pu, and 114 each for /sup 239/Pu and /sup 240/Pu. A complete breakdown by sample category, atoll or island, and radionuclide is also included.

  9. The feasibility of using Pu discharges from Sellafield to investigate the sediment dynamics of the Severn Estuary and the Welsh coast

    Energy Technology Data Exchange (ETDEWEB)

    Dunne, J.A.; Richards, D.A. [School of Geographical Sciences and Bristol Isotope Group, University of Bristol (United Kingdom)

    2014-07-01

    Decades of nuclear weapons testing and very low level radioactive waste discharges from civil nuclear sites have resulted in a global distribution of Pu isotopes. Given that the sources of these isotopes are spatially and temporally well-known, their distribution throughout the environment can provide insight into the processes that have governed their dispersal. Plutonium-239 and {sup 240}Pu have long half-lives and their atomic abundance ratio is indicative of the source, be it atmospheric fallout or releases from the nuclear industry. Plutonium is also strongly adsorbed on sediments. These characteristics make Pu an excellent tool for monitoring ocean currents, tracking sediment transport and examining the fate of the products of nuclear activities. We intend to exploit the discharges of Pu from Sellafield nuclear reprocessing plant to investigate transit times and sediment regime in inter-tidal sediments from proximal (Ravenglass Estuary, Cumbria) and distal (Portishead, North Somerset) sites. Continuing developments in analytical techniques (extraction chromatography and ion exchange) and inductively coupled plasma mass spectrometry (ICP-MS) permit isotopic analysis at low abundances (on the order of femto-grams), with reasonable efficiency and cost in comparison to traditional radiometric techniques. A major advantage of this technique is the ability to distinguish between {sup 239}Pu and {sup 240}Pu, which is not possible with alpha-spectrometry due to similar alpha energies. We present initial results using MC-ICP-MS, following methods in Lindahl et al. (2011). Document available in abstract form only. (authors)

  10. Polonium-210 in mussels and its implications for environmental alpha-autoradiography

    Energy Technology Data Exchange (ETDEWEB)

    McDonald, P.; Baxter, M.S.; Fowler, S.W.; Heyraud, M.

    1986-01-01

    Alpha-autoradiographic and radiochemical studies of the distributions of transuranic nuclides in the tissues and organs of mussels collected from the vicinity of the British Nuclear Fuels reprocessing plant at Sellafield, England, appeared to require assessment also of baseline alpha-activities of natural /sup 210/ Po levels. To ensure that the levels of /sup 210/Po in Cumbrian mussels were not artificially enhanced by local discharges, mussels from remote British and French coastal sites were also analysed. General similarities in /sup 210/Po concentrations found in mussel soft parts suggest that the /sup 210/Po levels in the Ravenglass mussels are natural and largely unsupported by /sup 210/Pb; however these levels are as much as four times greater than the present day /sup 239 +240/Pu concentrations in the same samples. These findings severely limit the usefulness of alpha-autoradiography studies for transuranic nuclides performed on such samples. Because of the recently lower concentrations of alpha-emitting transuranic nuclides (mainly /sup 238/Pu, /sup 239 +240/Pu and /sup 241/Am) in the Ravenglass environment, natural /sup 210/Po is now a major contributor to alpha-track distributions in auto-radiographic studies.

  11. Main results of the 2012 joint Norwegian-Russian expedition to the dumping sites of the nuclear submarine K-27 and solid radioactive waste in Stepovogo Fjord, Novaya Zemlya.

    Science.gov (United States)

    Gwynn, Justin P; Nikitin, Aleksander; Shershakov, Viacheslav; Heldal, Hilde Elise; Lind, Bjørn; Teien, Hans-Christian; Lind, Ole Christian; Sidhu, Rajdeep Singh; Bakke, Gunnar; Kazennov, Alexey; Grishin, Denis; Fedorova, Anastasia; Blinova, Oxana; Sværen, Ingrid; Lee Liebig, Penny; Salbu, Brit; Wendell, Cato Christian; Strålberg, Elisabeth; Valetova, Nailja; Petrenko, Galina; Katrich, Ivan; Logoyda, Igor; Osvath, Iolanda; Levy, Isabelle; Bartocci, Jean; Pham, Mai Khanh; Sam, Adam; Nies, Hartmut; Rudjord, Anne Liv

    2016-01-01

    This paper reports the main results of the 2012 joint Norwegian-Russian expedition to investigate the radioecological situation of the Stepovogo Fjord on the eastern coast of Novaya Zemlya, where the nuclear submarine K-27 and solid radioactive waste was dumped. Based on in situ gamma measurements and the analysis of seawater and sediment samples taken around the submarine, there was no indication of any leakage from the reactor units of K-27. With regard to the radioecological status of Stepovogo Fjord, activity concentrations of all radionuclides in seawater, sediment and biota in 2012 were in general lower than reported from the previous investigations in the 1990s. However in 2012, the activity concentrations of (137)Cs and, to a lesser extent, those of (90)Sr remained elevated in bottom water from the inner part of Stepovogo Fjord compared with surface water and the outer part of Stepovogo Fjord. Deviations from expected (238)Pu/(239,240)Pu activity ratios and (240)Pu/(239)Pu atom ratios in some sediment samples from the inner part of Stepovogo Fjord observed in this study and earlier studies may indicate the possibility of leakages from dumped waste from different nuclear sources. Although the current environmental levels of radionuclides in Stepovogo Fjord are not of immediate cause for concern, further monitoring of the situation is warranted.

  12. The significance of distribution coefficients in the remobilisation of actinides from intertidal sediments of the Ravenglass Estuary

    International Nuclear Information System (INIS)

    Distribution coefficients (Ksub(d)) were determined for desorption of actinides from Ravenglass Estuary intertidal sediment into 'inactive' seawater from the North Sea. Values of 1.1 x 106 for 239+240Pu and 2.0 x 106 from 241Am were obtained. Further experiments indicated the desorption-sorption equilibrium reaction for plutonium is an oxidation-reduction process, the sediment itself able to reduce Pu V+VI to Pu III+IV, whereas for americium the formation of a soluble carbonate complex is thought to occur. Using seawater diluted with river water, Ksub(d) values were found to decrease by approx. two orders of magnitude at low values of salinity, characteristic of low tide conditions and in the upper estuary. Tidal balance experiments indicated the Ravenglass Estuary currently acts as a radionuclide source to the Irish Sea, actinides being lost from the estuary in suspended sediment. Distribution coefficients for 239+240Pu measured during three tidal cycles were approx. = 106 at low water but decreasing rapidly on the flood. The effect was more pronounced in calm conditions and did not follow the relationship between desorption ksub(d) and salinity observed in the laboratory experiments. (author)

  13. Measurements of low-level anthropogenic radionuclides from soils around Maralinga

    Science.gov (United States)

    Tims, Stephen G.; Tsifakis, Dimitrios; Srncik, Michaela; Fifield, L. Keith; Hancock, Gary J.; De Cesare, Mario

    2013-12-01

    The isotopes 239Pu and 240Pu are present in surface soils as a result of global fallout from nuclear weapons tests carried out in the 1950's and 1960's. These isotopes constitute artificial tracers of recent soil erosion and sediment movement. In practice the high throughput capabilities and high sensitivity of the AMS technique makes the study of Australia's geographically large areas viable using Pu isotopes. As part of its weapons development program the United Kingdom carried out a series of atmospheric and surface nuclear weapons tests at Maralinga, South Australia in 1956 and 1957. The contribution from the Maralinga tests to the Pu isotopic abundances present in the region around Maralinga is largely unknown. In global fallout, for example, the 240Pu/239Pu ratio is typically in the range 0.17 - 0.19, but the influence of the regional tests could lead to values outside this range. This would impact on the assessment techniques used in the soil and sediment tracer studies. We report recent measurements on soil samples collected from across the Maralinga Test site.

  14. Measurements of low-level anthropogenic radionuclides from soils around Maralinga

    Directory of Open Access Journals (Sweden)

    Tims Stephen G.

    2013-12-01

    Full Text Available The isotopes 239Pu and 240Pu are present in surface soils as a result of global fallout from nuclear weapons tests carried out in the 1950’s and 1960’s. These isotopes constitute artificial tracers of recent soil erosion and sediment movement. In practice the high throughput capabilities and high sensitivity of the AMS technique makes the study of Australia’s geographically large areas viable using Pu isotopes. As part of its weapons development program the United Kingdom carried out a series of atmospheric and surface nuclear weapons tests at Maralinga, South Australia in 1956 and 1957. The contribution from the Maralinga tests to the Pu isotopic abundances present in the region around Maralinga is largely unknown. In global fallout, for example, the 240Pu/239Pu ratio is typically in the range 0.17 - 0.19, but the influence of the regional tests could lead to values outside this range. This would impact on the assessment techniques used in the soil and sediment tracer studies. We report recent measurements on soil samples collected from across the Maralinga Test site.

  15. Plutonium release from Fukushima Daiichi fosters the need for more detailed investigations

    Science.gov (United States)

    Schneider, Stephanie; Walther, Clemens; Bister, Stefan; Schauer, Viktoria; Christl, Marcus; Synal, Hans-Arno; Shozugawa, Katsumi; Steinhauser, Georg

    2013-10-01

    The contamination of Japan after the Fukushima accident has been investigated mainly for volatile fission products, but only sparsely for actinides such as plutonium. Only small releases of actinides were estimated in Fukushima. Plutonium is still omnipresent in the environment from previous atmospheric nuclear weapons tests. We investigated soil and plants sampled at different hot spots in Japan, searching for reactor-borne plutonium using its isotopic ratio 240Pu/239Pu. By using accelerator mass spectrometry, we clearly demonstrated the release of Pu from the Fukushima Daiichi power plant: While most samples contained only the radionuclide signature of fallout plutonium, there is at least one vegetation sample whose isotope ratio (0.381 +/- 0.046) evidences that the Pu originates from a nuclear reactor (239+240Pu activity concentration 0.49 Bq/kg). Plutonium content and isotope ratios differ considerably even for very close sampling locations, e.g. the soil and the plants growing on it. This strong localization indicates a particulate Pu release, which is of high radiological risk if incorporated.

  16. Vertical distribution and migration of global fallout Pu in forest soils in southwestern China

    International Nuclear Information System (INIS)

    Soil samples collected in southwestern China were analyzed for Pu isotopes. The 240Pu/239Pu atom ratios were around 0.18, which indicated the dominant source of global fallout. Consistent sub-surface maximums followed by exponential decline of 239+240Pu activities in the soil cores were observed. Most of the Pu has still remained in the 0–10 cm layers since its deposition. Convection velocities and dispersion coefficients for Pu migration in the soils were estimated by the convection–dispersion equation (CDE) model. The effective convection velocities and effective dispersion coefficients ranged from 0.05 to 0.11 cm/y and from 0.06 to 0.29 cm2/y, respectively. Other factors that control the vertical migration of Pu in soil besides precipitation, soil particle size distribution and organic matter were suggested. Long-term migration behaviors of Pu in the soils were simulated. The results provide the Pu background baseline for further environmental monitoring and source identification of non-global fallout Pu inputs in the future. - Highlights: • Pu isotopes in the soil cores collected in southwestern China were analyzed. • Background baseline data of Pu isotopes in the soils were given. • Parameters of convection–dispersion equation model for Pu migration were estimated. • Long-term migration behavior of Pu in soil was simulated

  17. Cycling of transuranic radionuclides in the Columbia River, its estuary and the northeast Pacific Ocean. Progress report, January-December 1984

    International Nuclear Information System (INIS)

    This report summarizes progress from 1 January 1984 to 31 December 1984 in research dealing with the behavior of transuranic and other long-lived radionuclides in the Columbia River downstream from the Hanford Reservation and in the northeast Pacific Ocean. Goals achieved include: The analysis of thirteen continental slope cores for 137Cs, /sup 239, 240/Pu and 241Am is complete; while 210Pb, C, and P analyses continue. The analysis of composite river sediment samples for 63Ni inventory in lower river reaches was done. Mass spectrometry analysis of fish, mussels, and plankton determined the isotopic composition of plutonium during 1962 to 1980. A new standard reference material was analyzed in collaboration with the National Bureau of Standards for 137Cs, /sup 239, 240/Pu, /sup 234, 238/U, thorium isotopes, 210Pb and 241Am as well as mass spectrometry analyses on the Pu fraction separated from this sample. Participation in a blind intercalibration exercise was sponsored by the IAEA for the measurement of radionuclides and trace metals in a North Sea marine sediment. A seminar presentation reviewed technetium behavior in the marine ecosystem

  18. Characterization and source term assessments of radioactive particles from Marshall Islands using non-destructive analytical techniques

    Energy Technology Data Exchange (ETDEWEB)

    Jernstroem, J. [Laboratory of Radiochemistry, Department of Chemistry, P.O. Box 55, FI-00014 University of Helsinki (Finland)]. E-mail: jussi.jernstrom@helsinki.fi; Eriksson, M. [IAEA-MEL, International Atomic Energy Agency - Marine Environment Laboratory, 4 Quai Antoine 1er, MC 98000 Monaco (Monaco); Simon, R. [Institute for Synchrotron Radiation, Forschungszentrum Karlsruhe GmbH, D-76021 Karlsruhe (Germany); Tamborini, G. [European Commission, Joint Research Centre, Institute for Transuranium Elements, P.O. Box 2340, D-76125 Karlsruhe (Germany); Bildstein, O. [European Commission, Joint Research Centre, Institute for Transuranium Elements, P.O. Box 2340, D-76125 Karlsruhe (Germany); Marquez, R. Carlos [European Commission, Joint Research Centre, Institute for Transuranium Elements, P.O. Box 2340, D-76125 Karlsruhe (Germany); Kehl, S.R. [Lawrence Livermore National Laboratory, P.O. Box 808, Livermore, CA 94551-0808 (United States); Hamilton, T.F. [Lawrence Livermore National Laboratory, P.O. Box 808, Livermore, CA 94551-0808 (United States); Ranebo, Y. [European Commission, Joint Research Centre, Institute for Transuranium Elements, P.O. Box 2340, D-76125 Karlsruhe (Germany); Betti, M. [European Commission, Joint Research Centre, Institute for Transuranium Elements, P.O. Box 2340, D-76125 Karlsruhe (Germany)]. E-mail: maria.betti@ec.europa.eu

    2006-08-15

    Six plutonium-containing particles stemming from Runit Island soil (Marshall Islands) were characterized by non-destructive analytical and microanalytical methods. Composition and elemental distribution in the particles were studied with synchrotron radiation based micro X-ray fluorescence spectrometry. Scanning electron microscope equipped with energy dispersive X-ray detector and with wavelength dispersive system as well as a secondary ion mass spectrometer were used to examine particle surfaces. Based on the elemental composition the particles were divided into two groups: particles with pure Pu matrix, and particles where the plutonium is included in Si/O-rich matrix being more heterogenously distributed. All of the particles were identified as nuclear fuel fragments of exploded weapon components. As containing plutonium with low {sup 240}Pu/{sup 239}Pu atomic ratio, less than 0.065, which corresponds to weapons-grade plutonium or a detonation with low fission yield, the particles were identified to originate from the safety test and low-yield tests conducted in the history of Runit Island. The Si/O-rich particles contained traces of {sup 137}Cs ({sup 239+240}Pu/{sup 137}Cs activity ratio higher than 2500), which indicated that a minor fission process occurred during the explosion. The average {sup 241}Am/{sup 239}Pu atomic ratio in the six particles was 3.7 x 10{sup -3} {+-} 0.2 x 10{sup -3} (February 2006), which indicated that plutonium in the different particles had similar age.

  19. Characterization and source term assessments of radioactive particles from Marshall Islands using non-destructive analytical techniques

    Science.gov (United States)

    Jernström, J.; Eriksson, M.; Simon, R.; Tamborini, G.; Bildstein, O.; Marquez, R. Carlos; Kehl, S. R.; Hamilton, T. F.; Ranebo, Y.; Betti, M.

    2006-08-01

    Six plutonium-containing particles stemming from Runit Island soil (Marshall Islands) were characterized by non-destructive analytical and microanalytical methods. Composition and elemental distribution in the particles were studied with synchrotron radiation based micro X-ray fluorescence spectrometry. Scanning electron microscope equipped with energy dispersive X-ray detector and with wavelength dispersive system as well as a secondary ion mass spectrometer were used to examine particle surfaces. Based on the elemental composition the particles were divided into two groups: particles with pure Pu matrix, and particles where the plutonium is included in Si/O-rich matrix being more heterogenously distributed. All of the particles were identified as nuclear fuel fragments of exploded weapon components. As containing plutonium with low 240Pu/ 239Pu atomic ratio, less than 0.065, which corresponds to weapons-grade plutonium or a detonation with low fission yield, the particles were identified to originate from the safety test and low-yield tests conducted in the history of Runit Island. The Si/O-rich particles contained traces of 137Cs ( 239 + 240 Pu/ 137Cs activity ratio higher than 2500), which indicated that a minor fission process occurred during the explosion. The average 241Am/ 239Pu atomic ratio in the six particles was 3.7 × 10 - 3 ± 0.2 × 10 - 3 (February 2006), which indicated that plutonium in the different particles had similar age.

  20. Accumulation and potential dissolution of Chernobyl-derived radionuclides in river bottom sediment

    Energy Technology Data Exchange (ETDEWEB)

    Sanada, Yukihisa E-mail: sanada@tokai.jnc.go.jp; Matsunaga, Takeshi; Yanase, Nobuyuki; Nagao, Seiya; Amano, Hikaru; Takada, Hideshige; Tkachenko, Yuri

    2002-05-01

    Areas contaminated with radionuclides from the Chernobyl nuclear accident have been identified in Pripyat River near the Chernobyl Nuclear Power Plant. The river bottom sediment cores contained {sup 137}Cs (10{sup 5}- 10{sup 6} Bq/m{sup 2}) within 0-30 cm depth, whose concentration is comparable to that in the ground soil in the vicinity of the nuclear power plant (the Exclusion Zone). The sediment cores also accumulated {sup 90}Sr (10{sup 5} Bq/m{sup 2}), {sup 239,240}Pu (10{sup 4} Bq/m{sup 2}) and {sup 241}Am (10{sup 4} Bq/m{sup 2}) derived from the accident. Several nuclear fuel particles have been preserved at 20-25 cm depth that is the peak area of the concentrations of the radionuclides. Th ese inventories in the bottom sediments were compared with those of the released radionuclides during the accident. An analysis using a selective sequential extraction technique was applied for the radionuclides in the sediments. Results suggest that the possibility of release of {sup 137}Cs and {sup 239,240}Pu from the bottom sediment was low compared with {sup 90}Sr. The potential dissolution and subsequent transport of {sup 90}Sr from the river bottom sediment should be taken into account with respect to the long-term radiological influence on the aquatic environment.

  1. Actinide measurements by AMS using fluoride matrices

    Science.gov (United States)

    Cornett, R. J.; Kazi, Z. H.; Zhao, X.-L.; Chartrand, M. G.; Charles, R. J.; Kieser, W. E.

    2015-10-01

    Actinides can be measured by alpha spectroscopy (AS), mass spectroscopy or accelerator mass spectrometry (AMS). We tested a simple method to separate Pu and Am isotopes from the sample matrix using a single extraction chromatography column. The actinides in the column eluent were then measured by AS or AMS using a fluoride target matrix. Pu and Am were coprecipitated with NdF3. The strongest AMS beams of Pu and Am were produced when there was a large excess of fluoride donor atoms in the target and the NdF3 precipitates were diluted about 6-8 fold with PbF2. The measured concentrations of 239,240Pu and 241Am agreed with the concentrations in standards of known activity and with two IAEA certified reference materials. Measurements of 239,240Pu and 241Am made at A.E. Lalonde AMS Laboratory agree, within their statistical uncertainty, with independent measurements made using the IsoTrace AMS system. This work demonstrated that fluoride targets can produce reliable beams of actinide anions and that the measurement of actinides using fluorides agree with published values in certified reference materials.

  2. Plutonium Detection with Straw Neutron Detectors

    Energy Technology Data Exchange (ETDEWEB)

    Mukhopadhyay, Sanjoy; Maurer, Richard; Guss, Paul

    2014-03-27

    A kilogram of weapons grade plutonium gives off about 56,000 neutrons per second of which 55,000 neutrons come from spontaneous fission of 240Pu (~6% by weight of the total plutonium). Actually, all even numbered isotopes (238Pu, 240Pu, and 242Pu) produce copious spontaneous fission neutrons. These neutrons induce fission in the surrounding fissile 239Pu with an approximate multiplication of a factor of ~1.9. This multiplication depends on the shape of the fissile materials and the surrounding material. These neutrons (typically of energy 2 MeV and air scattering mean free path >100 meters) can be detected 100 meters away from the source by vehicle-portable neutron detectors. [1] In our current studies on neutron detection techniques, without using 3He gas proportional counters, we designed and developed a portable high-efficiency neutron multiplicity counter using 10B-coated thin tubes called straws. The detector was designed to perform like commercially available fission meters (manufactured by Ortec Corp.) except instead of using 3He gas as a neutron conversion material, we used a thin coating of 10B.

  3. {\\alpha}-accompanied cold ternary fission of $^{238-244}$Pu isotopes in equatorial and collinear configuration

    CERN Document Server

    Santhosh, K P; Priyanka, B

    2015-01-01

    The cold ternary fission of $^{238}$Pu, $^{240}$Pu, $^{242}$Pu and $^{244}$Pu isotopes, with $^{4}$He as light charged particle, in equatorial and collinear configuration has been studied within the Unified ternary fission model (UTFM). The fragment combination $^{100}$Zr+$^{4}$He+$^{134}$Te possessing the near doubly magic nuclei $^{134}$Te (N=82, Z=52) gives the highest yield in the alpha accompanied ternary fission of $^{238}$Pu. For the alpha accompanied ternary fission of $^{240}$Pu, $^{242}$Pu and $^{244}$Pu isotopes, the highest yield was found for the fragment combination with doubly magic nuclei $^{132}$Sn (N=82, Z=50) as the heavier fragment. The deformation and orientation of fragments have also been taken into account for the alpha accompanied ternary fission of $^{238-244}$Pu isotopes, and it has been found that in addition to closed shell effect, ground state deformation also plays an important role in determining the isotopic yield in the ternary fission process. The emission probability and ki...

  4. First AID (Atom counting for Isotopic Determination).

    Energy Technology Data Exchange (ETDEWEB)

    Roach, J. L. (Jeffrey L.); Israel, K. M. (Kimberly M.); Steiner, R. E. (Robert E.); Duffy, C. J. (Clarence J.); Roench, F. R. (Fred R.)

    2002-01-01

    Los Alamos National Laboratory (LANL) has established an in vitro bioassay monitoring program in compliance with the requirements in the Code of Federal Regulations, 10 CFR 835, Occupational Radiation Protection. One aspect of this program involves monitoring plutonium levels in at-risk workers. High-risk workers are monitored using the ultra-sensitive Therrnal Ionization Mass Spectrometry (TIMS) technique to ensure compliance with DOE standards. TIMS is used to measure atom ratios of 239Pua nd 240Puw ith respect to a tracer isotope ('Pu). These ratios are then used to calculate the amount of 239Pu and 240Pup resent. This low-level atom counting technique allows the calculation of the concentration levels of 239Pu and 240Pu in urine for at risk workers. From these concentration levels, dose assessments can be made and worker exposure levels can be monitored. Detection limits for TIMS analysis are on the order of millions of atoms, which translates to activity levels of 150 aCi 239Pua nd 500 aCi for 240Pu. pCi for Our poster presentation will discuss the ultra-sensitive, low-level analytical technique used to measure plutonium isotopes and the data verification methods used for validating isotopic measurements.

  5. Attempted validation of ICRP 30 and ICRP 66 respiratory models

    International Nuclear Information System (INIS)

    The validation of human biological models for inhaled radionuclides is nearly impossible. Requirements for validation are: (1) the measurement of the relevant human tissue data and (2) valid exposure measurements over the interval known to apply to tissue uptake. Two lung models, ICRP 30(1) and ICRP 66(2), are widely used to estimate lung doses following acute occupational or environmental exposure. Both ICRP 30 and 66 lung models are structured to estimate acute rather than chronic exposure. Two sets of human tissue measurements are available: 210Po accumulated in tissue from inhaled cigarettes and ingested in diet and airborne global fallout 239,240Pu accumulated in the lungs from inhalation. The human tissue measurements include pulmonary and bronchial tissue in smokers, ex-smokers and non-smokers analysed radiochemically for 210Po, and pulmonary, bronchial and lymph nodes analysed for 239,240Pu in lung tissue collected by the New York City Medical Examiner from 1972 to 1974. Both ICRP 30 and 66 models were included in a programme to accommodate chronic uptake. Neither lung model accurately described the estimated tissue concentrations but was within a factor of 2 from measurements. ICRP 66 was the exception and consistently overestimated the bronchial concentrations probably because of its assumption of an overly long 23-d clearance half-time in the bronchi and bronchioles. (authors)

  6. ZZ ABBN, 26 Group Cross-Sections and Self Shielding Factors for Fast Reactors

    International Nuclear Information System (INIS)

    1 - Description of program or function: Format: special format; Number of groups: 26 group X-section and resonance self-shielding factor library. Nuclides: H, D, Li-6, Li-7, Be, B-10, B-11, C, N, O, Na, Mg, Al, Si, K, Ca, Ti, V, Cr, Fe, Ni, Cu, Zr, Nb, Mo, Ta, W, Re, Pb, Bi, Th-232, U-233, U-234, U-235, U-236, U-238, Pu-239, Pu-240, Pu-241, Pu-242, FP-U-233, FP-U-235, FP-Pu-239. Origin: Multiple experimental sources; Weighting spectrum: yes; 26 group cross section and resonance self-shielding factor library for the following materials: H, D, Li-6, Li-7, Be, B-10, B-11, C, N, O, Na, Mg, Al, Si, K, Ca, Ti, V, Cr, Fe, Ni, Cu, Zr, Nb, Mo, Ta, W, Re, Pb, Bi, Th-232, U-233, U-234, U-235, U-236, U-238, Pu-239, Pu-240, Pu-241, Pu-242, FP-U-233, FP-U-235, FP-Pu-239. 2 - Restrictions on the complexity of the problem: This group cross section library has been developed for fast and intermediate reactors

  7. Nuclear structure of 241Pu from neutron-capture, (d,p)-, and (d,t)-reaction measurements

    International Nuclear Information System (INIS)

    We report experimental measurements in 241Pu of the following: primary and secondary γ rays and conversion electrons from thermal neutron capture in 240Pu;γ rays from 245Cm α decay; proton and triton spectra, respectively, from (d,p) and (d,t) reactions on 240Pu and 242Pu targets. From these data and those of other investigations, we have identified 53 excited levels in 241Pu below 1400 keV. Of these, 44 are placed in 10 rotational bands (with connecting transitions) that have been assigned Nilsson configurations. For the bands below 1 MeV in 241Pu that are largely of single-particle character, there is good correspondence with similar bands in 239U and with the theoretical model of Gareev et al. For those bands in 241Pu where there is mixing between single-particle and vibrational modes, we find some significant deviations from theoretical predictions. For example, the (5) /(2) [622]circle-times 0- state at 519 keV appears to mix less with other states than predicted, while a trio of Kπ= (1) /(2) - bands show unexpected mixing patterns. copyright 1998 The American Physical Society

  8. A low-level laboratory for alpha and gamma counting of environmental samples

    International Nuclear Information System (INIS)

    The development of a low-level counting laboratory for the measurement of alpha- and gamma-ray emitting radionuclides in environmental samples is presented. A microcomputer-based counting system has been set up which consists of 12 Si-surface barrier detectors and four Ge(Li) detectors and associated analog-to-digital converters interfaced to a Nuclear Data Corporation ND6620 data acquisition and processing system. Sample preparation includes Ge(Li) detector calibration of a few container sizes and several counting matrix densities. A procedure for 241Pu analysis has been adapted for a low-level liquid scintillation counter and used to measure samples collected at several atolls in the Marshall Islands. The 241Pu/sup(239,240)Pu ratio is generally approximately 20 when decay-corrected back to 1956. However, ratios of from 10 to 26 were measured, indicating that the 241Pu/sup(239,240)Pu ratios may be used to detect particular sources of plutonium isotopes, i.e. from different nuclear detonations or from nuclear waste disposal. Measurements of plutonium and 210Pb have been made of a nuclear waste disposal site 4000 m deep located off the coast of New York, USA. Because of the low-level activity of the plutonium present, measurement times often exceeded 10,000 min. The long-term reliability of the system is proved by these measurements and by the results of the interlaboratory calibration. (author)

  9. Separation Techniques for Quantification of Radionuclides in Environmental Samples

    Directory of Open Access Journals (Sweden)

    Dusan Galanda

    2009-01-01

    Full Text Available The reliable and quantitative measurement of radionuclides is important in order to determine environmental quality and radiation safety, and to monitor regulatory compliance. We examined soil samples from Podunajske Biskupice, near the city of Bratislava in the Slovak Republic, for the presence of several natural (238U, 232Th, 40K and anthropogenic (137Cs, 90Sr, 239Pu, 240Pu, 241Am radionuclides. The area is adjacent to a refinery and hazardous waste processing center, as well as the municipal incinerator plant, and so might possess an unusually high level of ecotoxic metals. We found that the levels of both naturally occurring and anthropogenic radionuclides fell within the expected ranges, indicating that these facilities pose no radiological threat to the local environment. During the course of our analysis, we modified existing techniques in order to allow us to handle the unusually large and complex samples that were needed to determine the levels of 239Pu, 240Pu, and 241Am activity. We also rated three commercial techniques for the separation of 90Sr from aqueous solutions and found that two of them, AnaLig Sr-01 and Empore Extraction Disks, were suitable for the quantitative and reliable separation of 90Sr, while the third, Sr-Spec Resin, was less so. The main criterion in evaluating these methods was the chemical recovery of 90Sr, which was less than we had expected. We also considered speed of separation and additional steps needed to prepare the sample for separation.

  10. Conversion electron spectrometry of Pu isotopes with a silicon drift detector.

    Science.gov (United States)

    Pommé, S; Paepen, J; Peräjärvi, K; Turunen, J; Pöllänen, R

    2016-03-01

    An electron spectrometry set-up was built at IRMM consisting of a vacuum chamber with a moveable source holder and windowless Peltier-cooled silicon drift detector (SDD). The SDD is well suited for measuring low-energy x rays and electrons emitted from thin radioactive sources with low self-absorption. The attainable energy resolution is better than 0.5keV for electrons of 30keV. It has been used to measure the conversion electron spectra of three plutonium isotopes, i.e. (238)Pu, (239)Pu, (240)Pu, as well as (241)Am (being a decay product of (241)Pu). The obtained mixed x-ray and electron spectra are compared with spectra obtained with a close-geometry set-up using another SDD in STUK and spectra measured with a Si(Li) detector at IRMM. The potential of conversion electron spectrometry for isotopic analysis of mixed plutonium samples is investigated. With respect to the (240)Pu/(239)Pu isotopic ratio, the conversion electron peaks of both isotopes are more clearly separated than their largely overlapping peaks in alpha spectra. PMID:26651177

  11. A nuclear criticality safety analysis of the PACT-8 melter for the INEL Pit-9 comprehensive demonstration project

    International Nuclear Information System (INIS)

    Between 1967 and 1969, ∼3100 m3 of transuranic (TRU) waste from the Rocky Flats Plant was buried with other hazardous and low-level radioactive wastes in a 40- x 116-m disposal pit located at the Idaho National Engineering Laboratory's Radioactive Waste Management Complex. This pit, designated as pit 9, is estimated to contain ∼40 Ci of 238Pu, 1.7 kCi of 239Pu, 0.4 kCi of 240Pu, 3.0 kCi of 240Pu, and 3.1 kCi of 241Am. During the nearly 30 yr that have elapsed since burial, normal surface-water movement coupled with the disintegration of the original containers have contributed to limited migration of radionuclides past the boundaries of the original disposal containers. Sensitivity to issues germane to buried TRU waste has led to the decision to retrieve this material. Because the remediation operations involve fissile materials, a credible nuclear criticality safety (NCS) analysis must be performed as part of the safety evaluation process to demonstrate the improbability of any contingencies contributing to an inadvertent criticality. Environmental NCS analyses are problematic because no experimental benchmarks with comparable ranges of scale and fissile material concentration exit that can be applied to environmental situations

  12. Radionuclide Concentration in Soils and Vegetation at Low-Level Radioactive Waste Disposal Area G during 2005

    Energy Technology Data Exchange (ETDEWEB)

    P.R. Fresquez; M.W. McNaughton; M.J. Winch

    2005-10-01

    Soil samples were collected at 15 locations and unwashed overstory and understory vegetation samples were collected from up to nine locations within and around the perimeter of Area G, the primary disposal facility for low-level radioactive solid waste at Los Alamos National Laboratory (LANL). Soil and plant samples were also collected from the proposed expansion area west of Area G for the purpose of gaining preoperational baseline data. Soil and plant samples were analyzed for radionuclides that have shown a history of detection in past years; these included {sup 3}H, {sup 238}Pu, {sup 239,240}Pu, {sup 241}Am, {sup 234}U, {sup 235}U, and {sup 238}U for soils and {sup 3}H, {sup 238}Pu, and {sup 239,240}Pu for plants. As in previous years, the highest levels of {sup 3}H in soils and vegetation were detected at the south portion of Area G near the {sup 3}H shafts; whereas, the highest concentrations of the Pu isotopes were detected in the northern and northeastern portions near the pads for transuranic waste. All concentrations of radionuclides in soils and vegetation, however, were still very low (pCi range) and far below LANL screening levels and regulatory standards.

  13. Plutonium isotopic composition by gamma-ray spectroscopy

    International Nuclear Information System (INIS)

    We discuss the general approach, computerized data analysis methods, and results of measurements to determine the isotopic composition of plutonium by gamma-ray spectroscopy. The simple techniques are designed to be applicable to samples of arbitrary size, geometry, chemical and isotopic composition that have attained 241Pu-237U equilibrium. The combination of the gamma spectroscopic measurement of isotopic composition coupled with calorimetric measurement of total sample power is shown to give a totally nondestructive determination of sample Pu mass with a precision of 0.6% for 1000-g samples of PuO2 with 12% 240Pu content. The precision of isotopic measurements depends upon many factors including sample size, sample geometry, and isotopic content. Typical ranges are found to be 238Pu, 239Pu, 0.1 to 0.5%; 240Pu, 2 to 5%; 241Pu, 0.3 to 0.7%; 242Pu (determined by isotopic correlation); and 241Am, 0.2 to 10%

  14. Quantifying Holocene and Anthropocene erosion rates with cosmogenic and fallout nuclides

    International Nuclear Information System (INIS)

    Short-lived cosmogenic nuclides, such as in-situ produced 14C in quartz, and fallout nuclides, such as 137Cs and 239,240Pu, are particularly suited to determine Holocene and/or anthropogenic rates of soil erosion. While fallout 137Cs has been widely used to study erosion processes, the methodology and application of the in-situ produced 14C and 239,240Pu are still somewhat experimental. In the case of in-situ 14C it are experimental/methodological obstacles that stand in the way of wider application, in the case of fallout plutonium it is down to neglect. This experimental/neglected status is a pity, since in situ 14C has the potential to allow resolving Holocene from longer-term Earth-surface process rates, whereas fallout Pu can be used to overcome difficulties in 137Cs methodology arising from the Chernobyl fallout (particularly in Europe) and the relative short half-life of radionuclides of Cs. The presentation will (i) introduce the intrinsic methodological benefits of in-situ produced radiocarbon and fallout plutonium, (ii) report on developmental work at CologneAMS to establish routine use of these nuclides and (iii) present a showcase application for fallout plutonium. (author)

  15. Preparation of a multi-isotope plutonium AMS standard and preliminary results of a first inter-lab comparison

    Science.gov (United States)

    Dittmann, B.-A.; Dunai, T. J.; Dewald, A.; Heinze, S.; Feuerstein, C.; Strub, E.; Fifield, L. K.; Froehlich, M. B.; Tims, S. G.; Wallner, A.; Christl, M.

    2015-10-01

    The motivation of this work is to establish a new multi-isotope plutonium standard for isotopic ratio measurements with accelerator mass spectrometry (AMS), since stocks of existing solutions are declining. To this end, certified reference materials (CRMs) of each of the individual isotopes 239Pu, 240Pu, 242Pu and 244Pu were obtained from JRC IRMM (Joint Research Center Institute for Reference Materials and Measurements). These certified reference materials (IRMM-081a, IRMM-083, IRMM-043 and IRMM-042a) were diluted with nitric acid and mixed to obtain a stock standard solution with an isotopic ratio of approximately 1.0:1.0:1.0:0.1 (239Pu:240Pu:242Pu:244Pu). From this stock solution, samples were prepared for measurement of the plutonium isotopic composition by AMS. These samples have been measured in a round-robin exercise between the AMS facilities at CologneAMS, at the ANU Canberra and ETH Zurich to verify the isotopic ratio and to demonstrate the reproducibility of the measurements. The results show good agreement both between the different AMS measurements and with the gravimetrically determined nominal ratios.

  16. Natural and artificial radionuclides in forest and bog soils: tracers for migration processes and soil development

    International Nuclear Information System (INIS)

    Radionuclide distributions in undisturbed forest and bog soils, mostly situated in Saxony, Germany (Erzgebirge), were studied. Low concentrations of naturally-occurring U and Th decay series nuclides, including 210Pb, and artificial radioisotopes (125Sb, 134Cs, 137Cs, 241Am) were determined using low-level γ-spectrometry. In addition, the activities of 238Pu and 239,240Pu were determined by radiochemical separation and α-spectrometry. 14C and excess 210Pb dating methods were used to date the sampled bog profiles. The different radionuclides show characteristic depth distributions in the forest and bog soil horizons, which were sub-sampled as thin slices. 125Sb, 241Am, 238Pu and 239,240Pu are strongly fixed in soil organic matter. In spruce forest soils, the influence of soil horizons with distinct properties dominates the vertical time-dependent distribution. In ombrotrophic bogs, the peak positions correlated with the year of maximum input of each nuclide. The Sb, Am and Pu ''time markers'' and the 14C and 210Pb dating results correspond very well. Although Cs seems to be relatively mobile in organic as well as mineral forest soil horizons, it is enriched in the organic material. In ombrotrophic bogs, Cs is very mobile in the peat deposit. In Sphagnum peat, Cs is translocated continuously towards the growing apices of the Sphagnum mosses, where it is accumulated. (orig.)

  17. Coincidence measurements of FFTF breeder fuel subassemblies

    International Nuclear Information System (INIS)

    A prototype coincidence counter developed to assay fast breeder reactor fuel was used to measure four fast-flux test facility subassemblies at the Hanford Engineering Development Laboratory in Richland, Washington. Plutonium contents in the four subassemblies ranged between 7.4 and 9.7 kg with corresponding 240Pu-effective contents between 0.9 and 1.2 kg. Large count rates were observed from the measurements, and plots of the data showed significant multiplication in the fuel. The measured data were corrected for deadtime and multiplication effects using established formulas. These corrections require accurate knowledge of the plutonium isotopics and 241Am content in the fuel. Multiplication-corrected coincidence count rates agreed with the expected count rates based on spontaneous fission-neutron emission rates. These measurements indicate that breeder fuel subassemblies with 240Pu-effective contents up to 1.2 kg can be nondestructively assayed using the shift-register electronics with the prototype counters. Measurements using the standard Los Alamos National Laboratory shift-register coincidence electronics unit can produce an assay value accurate to +-1% in 1000 s. The uncertainty results from counting statistics and deadtime-correction errors. 3 references, 8 figures, 8 tables

  18. Accumulation of artificial radionuclides in agricultural plants in the area used for surface nuclear tests

    International Nuclear Information System (INIS)

    The paper reports on the study of artificial radionuclide accumulation in agricultural crops grown at the territory with high concentration of radionuclides, and first of all – with high concentration of transuranium elements. As a result of this work, peculiarities of accumulation and distribution of artificial radionuclides in the vegetative and generative organs of the studied plants have been revealed. Basic accumulation factors have been found for 137Cs, 90Sr, 239+240Pu, and 241Am in agricultural products. Accumulation factor dependence on type of planting was found for the investigated types of plants. It has been found that the vegetative organs accumulate radionuclides most of all. - Highlights: • The experiment with plants was performed under natural conditions in the area of ground nuclear explosions at “Experimental field” site of the Semipalatinsk test site. • Nature of radionuclides distribution in different plant organs has been revealed. • Main accumulation factors for 137Cs, 90Sr, 239+240Pu and 241Am have been obtained for the crop products. • Obtained results are of particular importance in the issues related to assessments of radiological environmental contamination and its consequences

  19. Northern Marshall Islands radiological survey: sampling and analysis summary

    International Nuclear Information System (INIS)

    A radiological survey was conducted in the Northern Marshall Islands to document reamining external gamma exposures from nuclear tests conducted at Enewetak and Bikini Atolls. An additional program was later included to obtain terrestrial and marine samples for radiological dose assessment for current or potential atoll inhabitants. This report is the first of a series summarizing the results from the terrestrial and marine surveys. The sample collection and processing procedures and the general survey methodology are discussed; a summary of the collected samples and radionuclide analyses is presented. Over 5400 samples were collected from the 12 atolls and 2 islands and prepared for analysis including 3093 soil, 961 vegetation, 153 animal, 965 fish composite samples (average of 30 fish per sample), 101 clam, 50 lagoon water, 15 cistern water, 17 groundwater, and 85 lagoon sediment samples. A complete breakdown by sample type, atoll, and island is given here. The total number of analyses by radionuclide are 8840 for 241Am, 6569 for 137Cs, 4535 for 239+240Pu, 4431 for 90Sr, 1146 for 238Pu, 269 for 241Pu, and 114 each for 239Pu and 240Pu. A complete breakdown by sample category, atoll or island, and radionuclide is also included

  20. Radiochemical contamination of bottom sediments of some natural and artificial lakes of Middle East Poland

    International Nuclear Information System (INIS)

    An investigation of the presence of some radioactive isotopes in the bottom sediments of two lakes, Piaseczno and Masluchowskie (Middle East of Poland) has been performed. Similar measurements were done at the Zalew Zemborzycki artificial water reservoir, filled up few years after the most intensive period of atmospheric nuclear explosions. It was estimated, that the concentration of radionuclides, especially of artificial origin was much greater in natural lakes than in examined artificial one. That testifies for an accumulation of radioactive substances on the bottom of the water tanks. The confirmation of this thesis may be the fact, that 85% of 137Cs detected in Zalew Zemborzycki comes from Chernobyl fallout while in natural lakes this isotope amounts only to 56-60%. Other isotopes, such as 210Pb, 226Ra, and 224Ra were detected in significant amounts. The radioactivity of 239,240Pu isotopes reaches 2.2-2.6 Bq/kg for the lakes and 0.7 for Zalew Zemborzycki. The 238Pu to 239,240Pu ratio suggests, that detected plutonium comes from world fallout. (author)

  1. Radioactivity Levels in Kola Bay

    International Nuclear Information System (INIS)

    Sediment samples were collected in May 1995 from 16 locations in Kola Bay, North-west Russia, during an expedition starting from Murmansk and ending at Kildin Island in the Barents Sea. The purpose was to study the contamination level in an area with several potential sources of civilian and military radioactive pollution. 137Cs concentrations in the sediments, algae and benthic samples were low, but small particles containing 137Cs were separated from the sediment samples. All the sediments between the nuclear icebreaker base Atomflot and the open Barents Sea contained 60Co. Traces of 125Sb, 134Cs, 95Zr, 154Eu and 152Eu were also detected in some of the samples. Plutonium levels were low, but the increased 238Pu/239,240Pu ratio at Atomflot indicated a fresh release from the facility or from the waste storage vessels, Lepse and Imandra, lying in front of it. An increased 238Pu/239,240Pu ratio was also found in sediment collected in the outlet of Kola Bay in the Barents Sea. (author)

  2. Conversion electron spectrometry of Pu isotopes with a silicon drift detector.

    Science.gov (United States)

    Pommé, S; Paepen, J; Peräjärvi, K; Turunen, J; Pöllänen, R

    2016-03-01

    An electron spectrometry set-up was built at IRMM consisting of a vacuum chamber with a moveable source holder and windowless Peltier-cooled silicon drift detector (SDD). The SDD is well suited for measuring low-energy x rays and electrons emitted from thin radioactive sources with low self-absorption. The attainable energy resolution is better than 0.5keV for electrons of 30keV. It has been used to measure the conversion electron spectra of three plutonium isotopes, i.e. (238)Pu, (239)Pu, (240)Pu, as well as (241)Am (being a decay product of (241)Pu). The obtained mixed x-ray and electron spectra are compared with spectra obtained with a close-geometry set-up using another SDD in STUK and spectra measured with a Si(Li) detector at IRMM. The potential of conversion electron spectrometry for isotopic analysis of mixed plutonium samples is investigated. With respect to the (240)Pu/(239)Pu isotopic ratio, the conversion electron peaks of both isotopes are more clearly separated than their largely overlapping peaks in alpha spectra.

  3. Vertical distribution and migration of global fallout Pu in forest soils in southwestern China.

    Science.gov (United States)

    Bu, Wenting; Zheng, Jian; Guo, Qiuju; Uchida, Shigeo

    2014-10-01

    Soil samples collected in southwestern China were analyzed for Pu isotopes. The (240)Pu/(239)Pu atom ratios were around 0.18, which indicated the dominant source of global fallout. Consistent sub-surface maximums followed by exponential decline of (239+240)Pu activities in the soil cores were observed. Most of the Pu has still remained in the 0-10 cm layers since its deposition. Convection velocities and dispersion coefficients for Pu migration in the soils were estimated by the convection-dispersion equation (CDE) model. The effective convection velocities and effective dispersion coefficients ranged from 0.05 to 0.11 cm/y and from 0.06 to 0.29 cm(2)/y, respectively. Other factors that control the vertical migration of Pu in soil besides precipitation, soil particle size distribution and organic matter were suggested. Long-term migration behaviors of Pu in the soils were simulated. The results provide the Pu background baseline for further environmental monitoring and source identification of non-global fallout Pu inputs in the future.

  4. Vertical distributions of plutonium isotopes in marine sediment cores off the Fukushima coast after the Fukushima Dai-ichi Nuclear Power Plant accident

    Directory of Open Access Journals (Sweden)

    W. T. Bu

    2013-04-01

    Full Text Available The Fukushima Dai-ichi Nuclear Power Plant (FDNPP accident led to the release of large amounts of radionuclides into the atmosphere as well as direct discharges into the sea. In contrast to the intensive studies on the distribution of the released high volatility fission products, such as 131I, 134Cs and 137Cs, similar studies of the actinides, especially the Pu isotopes, are limited. To obtain the vertical distribution of Pu isotopes in marine sediments and to better assess the possible contamination of Pu from the FDNPP accident in the marine environment, we determined the activities of 239+240Pu and 241Pu as well as the atom ratios of 240Pu/239Pu and 241Pu/239Pu in sediment core samples collected in the western North Pacific off Fukushima from July 2011 to July 2012. We also measured surface sediment samples collected from seven Japanese estuaries before the FNDPP accident to establish the comprehensive background baseline data. The observed results of both the Pu activities and the Pu atom ratios for the sediments in the western North Pacific were comparable to the baseline data, suggesting that the FDNPP accident did not cause detectable Pu contamination to the studied regions prior to the sampling time. The Pu isotopes in the western North Pacific 30 km off the Fukushima coast originated from global fallout and Pacific Proving Ground close-in fallout.

  5. Plutonium isotopes in the terrestrial environment at the Savannah River Site, USA: a long-term study.

    Science.gov (United States)

    Armstrong, Christopher R; Nuessle, Patterson R; Brant, Heather A; Hall, Gregory; Halverson, Justin E; Cadieux, James R

    2015-02-01

    This work presents the findings of a long-term plutonium (Pu) study at Savannah River Site (SRS) conducted between 2003 and 2013. Terrestrial environmental samples were obtained at the Savannah River National Laboratory (SRNL) in the A-Area. Plutonium content and isotopic abundances were measured over this time period by α particle and thermal ionization mass spectrometry (3STIMS). We detail the complete process of the sample collection, radiochemical separation, and measurement procedure specifically targeted to trace plutonium in bulk environmental samples. Total plutonium activities were determined to be not significantly above atmospheric global fallout. However, the (238)Pu/(239+240)Pu activity ratios attributed to SRS are substantially different than fallout due to past (238)Pu production on the site. The (240)Pu/(239)Pu atom ratios are reasonably consistent from year to year and are lower than fallout indicating an admixture of weapons-grade material, while the (242)Pu/(239)Pu atom ratios are higher than fallout values, again due to actinide production activities. Overall, the plutonium signatures obtained in this study reflect a distinctive mixture of weapons-grade, heat source, and higher burn-up plutonium with fallout material. This study provides a unique opportunity for developing and demonstrating a blue print for long-term low-level monitoring of trace plutonium in the environment.

  6. Determination of plutonium content in high burnup pressurized water reactor fuel samples and its use for isotope correlations for isotopic composition of plutonium.

    Science.gov (United States)

    Joe, Kihsoo; Jeon, Young-Shin; Han, Sun-Ho; Lee, Chang-Heon; Ha, Yeong-Keong; Song, Kyuseok

    2012-06-01

    The content of plutonium isotopes in high burnup pressurized water reactor fuel samples was examined using both alpha spectrometry and mass spectrometry after anion exchange separation. The measured values were compared with results calculated by the ORIGEN-2 code. On average, the ratios (m/c) of the measured values (m) over the calculated values (c) were 1.22±0.16 for (238)Pu, 1.02±0.14 for (239)Pu, 1.08±0.06 for (240)Pu, 1.06±0.16 for (241)Pu, and 1.13±0.08 for (242)Pu. Using the Pu data obtained in this work, correlations were derived between the alpha activity ratios of (238)Pu/((239)Pu+(240)Pu), the alpha specific activities of Pu, and the atom % abundances of the Pu isotopes. Using these correlations, the atom % abundances of the plutonium isotopes in the target samples were calculated. These calculated results agreed within a range from 2 to 8% of the experimentally derived values according to the isotopes of plutonium.

  7. Twenty-four years of follow-up for a Hanford plutonium wound case.

    Science.gov (United States)

    Carbaugh, Eugene H; Lynch, Timothy P; Antonio, Cheryl L; Medina-Del Valle, Fernando

    2010-10-01

    A 1985 plutonium puncture wound resulted in the initial deposition of 48 kBq of transuranic alpha activity, primarily 239+240Pu and 241Am, in a worker's right index finger. Surgical excisions in the week following reduced the long-term residual wound activity to 5.4 kBq, and 164 DTPA chelation therapy administrations over 17 mo resulted in urinary excretion of about 7 kBq. The case was published in 1988, but now 24 y of follow-up data are available. Annual bioassays have included in-vivo measurements of 241Am in the wound, skeleton, liver, lung, and axillary lymph nodes, and urinalyses for plutonium and 241Am. These measurements have shown relatively stable levels of 241Am at the wound site, with gradually increasing amounts of 241Am detected in the skeleton. Liver measurements have shown erratic detection of 241Am, and the lung measurements indicate Am but as interference from activity in the axillary lymph nodes and skeleton rather than activity in the lung. Urine excretion of Pu since termination of chelation therapy has typically ranged from 10 to 20 mBq d, with Am excretion about 10% of that for 239+240Pu. Annual routine medical exams have not identified any adverse health effects associated with the intake.

  8. Plutonium, 241Am and 137Cs ratios, inventories and vertical profiles in Washington and Oregon continental shelf sediments

    Science.gov (United States)

    Beasley, T. M.; Carpenter, R.; Jennings, C. D.

    1982-10-01

    Continental shelf sediments from nine locations off Washington and Oregon have 239,240Pu inventories which average 8.0 ± 2.6 mCi/km 2. The Columbia River and seawaters advecting over the shelf supply Pu which is removed to underlying sediments, principally through scavenging by inorganic paniculate matter. Mass balance calculations argue that less than 20 percent of the advected Pu need be scavenged from the water column to balance river input and total shelf sediment inventories. The percentage of the Pu removed through scavenging is consistent with observed participate concentrations in shelf waters and published sediment/water distribution coefficients. No marked separation of Pu from 137Cs is observed with depth in Pacific shelf sediments as has been reported in Atlantic coastal sediments. This interocean distinctness can be explained by differences in particle mixing and downward diffusion of Cs in sediments of varying porosities. The transuranic inventories and Pu/Cs ratios in the Pacific sediments do not support the hypothesis of Livingston and Bowen that Pu is remobilized within the sediment column by 'complexone' formation with (principally) organic substances. Excess 210Pb/ 239,240Pu inventory ratios in eight representative cores from the Washington shelf average 100 ± 19, even though absolute values of both inventories vary by much larger factors. This reasonably constant ratio, for a given water depth, permits estimation of total Pu inventories and prediction of sites of unusual Pu accumulation from data on the more easily measured natural radionuclide.

  9. Application of inductively coupled plasma mass spectrometry to the study of environmental radioactivity

    International Nuclear Information System (INIS)

    Applications of inductively coupled plasma mass spectrometry (ICP-MS) to the determination of long-lived radionuclides in environmental samples were summarized. In order to predict the long-term behavior of the radionuclides, related stable elements were also determined. Compared with radioactivity measurements, the ICP-MS method has advantages in terms of its simple analytical procedures, prompt measurement time, and capability of determining the isotope ratio such as 240Pu/239Pu, which can not be separated by radiation. Concentration of U and Th in Japanese surface soils were determined in order to determine the background level of the natural radionuclides. The 235U/238U ratio was successfully used to detect the release of enriched U from reconversion facilities to the environment and to understand the source term. The 240Pu/239Pu ratios in environmental samples varied widely depending on the Pu sources. Applications of ICP-MS to the measurement of I and Tc isotopes were also described. The ratio between radiocesium and stable Cs is useful for judging the equilibrium of deposited radiocesium in a forest ecosystem. (author)

  10. Mechanical environmental transport of actinides and ¹³⁷Cs from an arid radioactive waste disposal site.

    Science.gov (United States)

    Snow, Mathew S; Clark, Sue B; Morrison, Samuel S; Watrous, Matthew G; Olson, John E; Snyder, Darin C

    2015-10-01

    Aeolian and pluvial processes represent important mechanisms for the movement of actinides and fission products at the Earth's surface. Soil samples taken in the early 1970's near a Department of Energy radioactive waste disposal site (the Subsurface Disposal Area, SDA, located in southeastern Idaho) provide a case study for studying the mechanisms and characteristics of environmental actinide and (137)Cs transport in an arid environment. Multi-component mixing models suggest actinide contamination within 2.5 km of the SDA can be described by mixing between 2 distinct SDA end members and regional nuclear weapons fallout. The absence of chemical fractionation between (241)Am and (239+240)Pu with depth for samples beyond the northeastern corner and lack of (241)Am in-growth over time (due to (241)Pu decay) suggest mechanical transport and mixing of discrete contaminated particles under arid conditions. Occasional samples northeast of the SDA (the direction of the prevailing winds) contain anomalously high concentrations of Pu with (240)Pu/(239)Pu isotopic ratios statistically identical to those in the northeastern corner. Taken together, these data suggest flooding resulted in mechanical transport of contaminated particles into the area between the SDA and a flood containment dike in the northeastern corner, following which subsequent contamination spreading in the northeastern direction resulted from wind transport of discrete particles.

  11. Correlation between strain and defects in Bi implanted Si

    Science.gov (United States)

    Palade, C.; Lepadatu, A.-M.; Slav, A.; Ciurea, M. L.; Lazanu, S.

    2016-06-01

    The strain in Si containing group-V impurities is a topical subject of study due to its potential applications in quantum computing. In this paper we study 209Bi implanted Si concerning the correlation between the strain produced by stopped Bi ions and trapping characteristics of the defects resulted from implantation. The depths distributions of stopped ions and primary defects are simulated and the distributions of permanent defects are modelled for Si implanted with low fluence 209Bi ions of 28 MeV kinetic energy. For comparison, these depths distributions were similarly calculated for 127I ions with the same fluence and energy, implanted in Si. The results are compared with each other and correlated with the characteristics of traps in these systems, previously obtained. We demonstrate that the intensity of the strain field is the most important factor in changing of trap parameters, while the superposition between the region with strain and the region where defects are located is a second order effect.

  12. NMR Evidence for the Topologically Nontrivial Nature in a Family of Half-Heusler Compounds

    Science.gov (United States)

    Zhang, Xiaoming; Hou, Zhipeng; Wang, Yue; Xu, Guizhou; Shi, Chenglong; Liu, Enke; Xi, Xuekui; Wang, Wenhong; Wu, Guangheng; Zhang, Xi-Xiang

    2016-03-01

    Spin-orbit coupling (SOC) is expected to partly determine the topologically nontrivial electronic structure of heavy half-Heusler ternary compounds. However, to date, attempts to experimentally observe either the strength of SOC or how it modifies the bulk band structure have been unsuccessful. By using bulk-sensitive nuclear magnetic resonance (NMR) spectroscopy combined with first-principles calculations, we reveal that 209Bi NMR isotropic shifts scale with relativity in terms of the strength of SOC and average atomic numbers, indicating strong relativistic effects on NMR parameters. According to first-principles calculations, we further claim that nuclear magnetic shieldings from relativistic p1/2 states and paramagnetic contributions from low-lying unoccupied p3/2 states are both sensitive to the details of band structures tuned by relativity, which explains why the hidden relativistic effects on band structure can be revealed by 209Bi NMR isotropic shifts in topologically nontrivial half-Heusler compounds. Used in complement to surface-sensitive methods, such as angle resolved photon electron spectroscopy and scanning tunneling spectroscopy, NMR can provide valuable information on bulk electronic states.

  13. Simulated nucleon–nucleon and nucleon–nucleus reactions in the frame of the cascade exciton model at high and intermediate energies

    Indian Academy of Sciences (India)

    A Abdel-Hafiez; Shaker El-Shater; M F Zaki

    2015-04-01

    In this study, we have used the cascade exciton model (CEM) to investigate different characteristics of nuclear reactions. Number of nucleon–nucleon collisions in Pb+Pb collisions as a function of impact parameter and rapidity distributions of negative particles from p+Ar and p+Xe interactions at lab = 200 GeV/c have been studied. We could create inclusive spectra of pions for separate charged states from reactions and total neutron multiplicities per primary reaction at 1000 MeV for different thin targets. Also, cross-sections for the reactions 209Bi(p, f) and 209Bi(n, f) were studied. Interactions of 1.0 GeV protons with C, Al, Cu, Sn, and Pb are presented in this study. All the calculated characteristics are compared with other theoretical calculations and compared with the experimental data. CEM shows good agreement with both theoretical and experimental results. In this study, we have used quantum molecular dynamic (QMD) as a theoretical model to compare our results.

  14. NMR Evidence for the Topologically Nontrivial Nature in a Family of Half-Heusler Compounds

    KAUST Repository

    Zhang, Xiaoming

    2016-03-16

    Spin-orbit coupling (SOC) is expected to partly determine the topologically nontrivial electronic structure of heavy half-Heusler ternary compounds. However, to date, attempts to experimentally observe either the strength of SOC or how it modifies the bulk band structure have been unsuccessful. By using bulk-sensitive nuclear magnetic resonance (NMR) spectroscopy combined with first-principles calculations, we reveal that 209Bi NMR isotropic shifts scale with relativity in terms of the strength of SOC and average atomic numbers, indicating strong relativistic effects on NMR parameters. According to first-principles calculations, we further claim that nuclear magnetic shieldings from relativistic p1/2 states and paramagnetic contributions from low-lying unoccupied p3/2 states are both sensitive to the details of band structures tuned by relativity, which explains why the hidden relativistic effects on band structure can be revealed by 209Bi NMR isotropic shifts in topologically nontrivial half-Heusler compounds. Used in complement to surface-sensitive methods, such as angle resolved photon electron spectroscopy and scanning tunneling spectroscopy, NMR can provide valuable information on bulk electronic states.

  15. Measurement of activation cross-sections for high-energy neutron-induced reactions of Bi and Pb

    Science.gov (United States)

    Zaman, Muhammad; Kim, Guinyun; Kim, Kwangsoo; Naik, Haladhara; Shahid, Muhammad; Lee, Manwoo

    2015-08-01

    The cross-sections for 209Bi(n, 4n)206Bi, 209Bi(n, 5n)205Bi, natPb(n, xn)204mPb, natPb(n, xn)203Pb, natPb(n, xn)202mPb,natPb(n, xn)201Pb, natPb(n, xn)200Pb, natPb(n, αxn)203Hg and natPb(n, p xn)202Tl reactions were determined at the Korean Institute of Radiological and Medical Sciences (KIRAMS), Korea in the neutron energy range of 15.2 to 37.2 MeV. The above cross-sections were obtained by using the activation and off-line γ-ray spectrometric technique. The quasi-monoenergetic neutron used for the above reactions are based on the 9Be(p, n) reaction. Simulations of the spectral flux from the Be target were done using the MCNPX program. The cross-sections were estimated with the TALYS 1.6 code using the default parameter. The data from the present work and literature were compared with the data from the EAF-2010 and the TENDL-2013 libraries, and calculated values of TALYS 1.6 code. It shows that appropriate level density model, the γ-ray strength function, and the spin cut-off parameter are needed to obtain a good agreement between experimental data and theoretical values from TALYS 1.6 code.

  16. Multiparticle emission in the pre-equilibrium decay of light and heavy nuclei in α-induced reaction up to 60 MeV

    International Nuclear Information System (INIS)

    α-particle induced excitation functions for the reactions 55Mn(α,n)58Co, 55Mn(α,2n)57Co, 55Mn(α,3n)56Co, 55Mn(α,4n)55Co, 55Mn(α,αn)54Mn, 55Mn(α,2p3n)54Mn, 55Mn(α,α3n)52Mn, 209Bi(α,3n)210At and 209Bi(α,4n)209At have been measured up to 60 MeV α-particle using the stack foil activation technique. The reactions 55Mn(α,4n)55Co and 55Mn(α,α3n)52Mn have been studied for the first time. The theoretical comparison with a pre-equilibrium (PE) geometry dependent hybrid (GHD) model has been made. The initial exciton number n0=4 with different configurations (1n+2p+1h), (2n+2p+0h) and (2n+1p+1h) has been tested. It is found that configuration (2n+2p+0h) is the best set of choice. The pre-equilibrium fraction fPE of the total excitation function has also been calculated at different excitation energy. (author). 23 refs, 10 figs, 2 tabs

  17. EA-MC Neutronic Calculations on IAEA ADS Benchmark 3.2

    International Nuclear Information System (INIS)

    The neutronics and the transmutation properties of the IAEA ADS benchmark 3.2 setup, the 'Yalina' experiment or ISTC project B-70, have been studied through an extensive amount of 3-D Monte Carlo calculations at CERN. The simulations were performed with the state-of-the-art computer code package EA-MC, developed at CERN. The calculational approach is outlined and the results are presented in accordance with the guidelines given in the benchmark description. A variety of experimental conditions and parameters are examined; three different fuel rod configurations and three types of neutron sources are applied to the system. Reactivity change effects introduced by removal of fuel rods in both central and peripheral positions are also computed. Irradiation samples located in a total of 8 geometrical positions are examined. Calculations of capture reaction rates in 129I, 237Np and 243Am samples and of fission reaction rates in 235U, 237Np and 243Am samples are presented. Simulated neutron flux densities and energy spectra as well as spectral indices inside experimental channels are also given according to benchmark specifications. Two different nuclear data libraries, JAR-95 and JENDL-3.2, are applied for the calculations

  18. Kilogram-scale purification of americium by ion exchange

    Energy Technology Data Exchange (ETDEWEB)

    Wheelwright, E. J.

    1979-01-01

    Sequential anion and cation exchange processes have been used for the final purification of /sup 241/Am recovered during the reprocessing of aged plutonium metallurgical scrap. Plutonium was removed by absorption of Dowex 1, X-3.5 (30 to 50 mesh) anion exchange resin from 6.5 to 7.5 M HNO/sub 3/ feed solution. Following a water dilution to 0.75 to 1.0 M HNO/sub 3/, americium was absorbed on Dowex 50W, X-8 (50 to 100 mesh) cation exchange resion. Final purification was accomplished by elution of the absorbed band down 3 to 4 successive beds of the same resin, preloaded with Zn/sup 2 +/, with an NH/sub 4/OH buffered chelating agent. The recovery of mixed /sup 241/Am-/sup 243/Am from power reactor reprocessing waste has been demonstrated. Solvent extraction was used to recover a HNO/sub 3/ solution of mixed lanthanides and actinides from waste generated by the reprocessng of 13.5 tons of Shippingport Power Reactor blanket fuel. Sequential cation exchange band-displacement processes were then used to separate americium and curium from the lanthanides and then to separate approx. 60 g of /sup 244/Cm from 1000 g of mixed /sup 241/Am-/sup 243/Am.

  19. Transuranium analysis methodologies for biological and environmental samples

    International Nuclear Information System (INIS)

    Analytical procedures for the most abundant transuranium nuclides in the environment (i.e., plutonium and, to a lesser extent, americium) are available. There is a lack of procedures for doing sequential analysis for Np, Pu, Am, and Cm in environmental samples, primarily because of current emphasis on Pu and Am. Reprocessing requirements and waste disposal connected with the fuel cycle indicate that neptunium and curium must be considered in environmental radioactive assessments. Therefore it was necessary to develop procedures that determine all four of these radionuclides in the environment. The state of the art of transuranium analysis methodology as applied to environmental samples is discussed relative to different sample sources, such as soil, vegetation, air, water, and animals. Isotope-dilution analysis with 243Am (239Np) and 236Pu or 242Pu radionuclide tracers is used. Americium and curium are analyzed as a group, with 243Am as the tracer. Sequential extraction procedures employing bis(2-ethyl-hexyl)orthophosphoric acid (HDEHP) were found to result in lower yields and higher Am--Cm fractionation than ion-exchange methods

  20. Estimation of Radiation Doses in the Marshall Islands Based on Whole Body Counting of Cesium-137 (137Cs) and Plutonium Urinalysis

    Energy Technology Data Exchange (ETDEWEB)

    Daniels, J; Hickman, D; Kehl, S; Hamilton, T

    2007-06-11

    Under the auspices of the U.S. Department of Energy (USDOE), researchers from the Lawrence Livermore National Laboratory (LLNL) have recently implemented a series of initiatives to address long-term radiological surveillance needs at former nuclear test sites in the Republic of the Marshall Islands (RMI). The aim of this radiological surveillance monitoring program (RSMP) is to provide timely radiation protection for individuals in the Marshall Islands with respect to two of the most important internally deposited fallout radionuclides-cesium-137 ({sup 137}Cs) and long-lived isotopes 239 and 240 of plutonium ({sup 239+240}Pu) (Robison et al., 1997 and references therein). Therefore, whole-body counting for {sup 137}Cs and a sensitive bioassay for the presence of {sup 239+240}Pu excreted in urine were adopted as the two most applicable in vivo analytical methods to assess radiation doses for individuals in the RMI from internally deposited fallout radionuclides (see Hamilton et al., 2006a-c; Bell et al., 2002). Through 2005, the USDOE has established three permanent whole-body counting facilities in the Marshall Islands: the Enewetak Radiological Laboratory on Enewetak Atoll, the Utrok Whole-Body Counting Facility on Majuro Atoll, and the Rongelap Whole-Body Counting Facility on Rongelap Atoll. These whole-body counting facilities are operated and maintained by trained Marshallese technicians. Scientists from LLNL provide the technical support and training necessary for maintaining quality assurance for data acquisition and dose reporting. This technical basis document summarizes the methodologies used to calculate the annual total effective dose equivalent (TEDE; or dose for the calendar year of measurement) based on whole-body counting of internally deposited {sup 137}Cs and the measurement of {sup 239+240}Pu excreted in urine. Whole-body counting provides a direct measure of the total amount (or burden) of {sup 137}Cs present in the human body at the time of

  1. Chronology of Pu isotopes and {sup 236}U in an Arctic ice core

    Energy Technology Data Exchange (ETDEWEB)

    Wendel, C.C., E-mail: cato.wendel@umb.no [Isotope Laboratory, Department of Plant and Environmental Sciences, Agricultural University of Norway, P.O. Box 5003, N-1432 Aas (Norway); Oughton, D.H., E-mail: deborah.oughton@umb.no [Isotope Laboratory, Department of Plant and Environmental Sciences, Agricultural University of Norway, P.O. Box 5003, N-1432 Aas (Norway); Lind, O.C., E-mail: ole-christian.lind@umb.no [Isotope Laboratory, Department of Plant and Environmental Sciences, Agricultural University of Norway, P.O. Box 5003, N-1432 Aas (Norway); Skipperud, L., E-mail: lindis.skipperud@umb.no [Isotope Laboratory, Department of Plant and Environmental Sciences, Agricultural University of Norway, P.O. Box 5003, N-1432 Aas (Norway); Fifield, L.K., E-mail: keith.fifield@anu.edu.au [Department of Nuclear Physics, Australian National University, Canberra ACT 0200 (Australia); Isaksson, E., E-mail: elisabeth.isaksson@npolar.no [Norwegian Polar Institute, Fram Centre, Hjalmar Johansens Gate 14, N9296 Tromsø (Norway); Tims, S.G., E-mail: steve.tims@anu.edu.au [Department of Nuclear Physics, Australian National University, Canberra ACT 0200 (Australia); Salbu, B., E-mail: brit.salbu@umb.no [Isotope Laboratory, Department of Plant and Environmental Sciences, Agricultural University of Norway, P.O. Box 5003, N-1432 Aas (Norway)

    2013-09-01

    In the present work, state of the art isotopic fingerprinting techniques are applied to an Arctic ice core in order to quantify deposition of U and Pu, and to identify possible tropospheric transport of debris from former Soviet Union test sites Semipalatinsk (Central Asia) and Novaya Zemlya (Arctic Ocean). An ice core chronology of {sup 236}U, {sup 239}Pu, and {sup 240}Pu concentrations, and atom ratios, measured by accelerator mass spectrometry in a 28.6 m deep ice core from the Austfonna glacier at Nordaustlandet, Svalbard is presented. The ice core chronology corresponds to the period 1949 to 1999. The main sources of Pu and {sup 236}U contamination in the Arctic were the atmospheric nuclear detonations in the period 1945 to 1980, as global fallout, and tropospheric fallout from the former Soviet Union test sites Novaya Zemlya and Semipalatinsk. Activity concentrations of {sup 239+240}Pu ranged from 0.008 to 0.254 mBq cm{sup −2} and {sup 236}U from 0.0039 to 0.053 μBq cm{sup −2}. Concentrations varied in concordance with {sup 137}Cs concentrations in the same ice core. In contrast to previous published results, the concentrations of Pu and {sup 236}U were found to be higher at depths corresponding to the pre-moratorium period (1949 to 1959) than to the post-moratorium period (1961 and 1962). The {sup 240}Pu/{sup 239}Pu ratio ranged from 0.15 to 0.19, and {sup 236}U/{sup 239}Pu ranged from 0.18 to 1.4. The Pu atom ratios ranged within the limits of global fallout in the most intensive period of nuclear atmospheric testing (1952 to 1962). To the best knowledge of the authors the present work is the first publication on biogeochemical cycles with respect to {sup 236}U concentrations and {sup 236}U/{sup 239}Pu atom ratios in the Arctic and in ice cores. - Highlights: • Concentrations and atom ratios of Pu and {sup 236}U determined in an Arctic ice core. • Concentrations of U and Pu found to be higher pre- than post-moratorium. • U and Pu concentrations

  2. Reconstruction of local fallout composition and gamma-ray exposure in a village contaminated by the first USSR nuclear test in the Semipalatinsk nuclear test site in Kazakhstan.

    Science.gov (United States)

    Imanaka, Tetsuji; Yamamoto, Masayoshi; Kawai, Kenta; Sakaguchi, Aya; Hoshi, Masaharu; Chaizhunusova, Nailya; Apsalikov, Kazbek

    2010-11-01

    After the disintegration of the USSR in end of 1991, it became possible for foreign scientists to visit Kazakhstan, in order to investigate the radiological consequences of nuclear explosions that had been conducted at the Semipalatinsk nuclear test site (SNTS). Since the first visit in 1994, our group has been continuing expeditions for soil sampling at various areas around SNTS. The current level of local fallout at SNTS was studied through γ-spectrometry for (137)Cs as well as α-spectrometry for (239,240)Pu. Average values of soil inventory from wide areas around SNTS were 3,500 and 3,700 Bq m(-2) for (137)Cs and (239,240)Pu, respectively, as of January 1, 2000. The average level of (137)Cs is comparable to that in Japan due to global fallout, while the level of (239,240)Pu is several tens of times larger than that in Japan. Areas of strong contamination were found along the trajectories of radioactive fallout, information on which was declassified after the collapse of the USSR. Our recent efforts of soil sampling were concentrated on the area around the Dolon village heavily affected by the radioactive plume from the first USSR atomic bomb test in 1949 and located 110 km east from ground zero of the explosion. Using soil inventory data, retrospective dosimetry was attempted by reconstructing γ-ray exposure from fission product nuclides deposited on the ground. Adopting representative parameters for the initial (137)Cs deposition (13 kBq m(-2)), the refractory/volatile deposition ratio (3.8) and the plume arrival time after explosion (2.5 h), an absorbed dose in air of 600 mGy was obtained for the 1-year cumulative dose in Dolon village, due to the first bomb test in 1949. Considering possible ranges of the parameters, 350 and 910 mGy were estimated for high and low cases of γ-ray dose in air, respectively. It was encouraging that the deduced value was consistent with other estimations using thermal luminescence and archived monitoring data. The present

  3. Radionuclides from the Fukushima accident in the air over Lithuania: measurement and modelling approaches

    International Nuclear Information System (INIS)

    Analyses of 131I, 137Cs and 134Cs in airborne aerosols were carried out in daily samples in Vilnius, Lithuania after the Fukushima accident during the period of March–April, 2011. The activity concentrations of 131I and 137Cs ranged from 12 μBq/m3 and 1.4 μBq/m3 to 3700 μBq/m3 and 1040 μBq/m3, respectively. The activity concentration of 239,240Pu in one aerosol sample collected from 23 March to 15 April, 2011 was found to be 44.5 nBq/m3. The two maxima found in radionuclide concentrations were related to complicated long-range air mass transport from Japan across the Pacific, the North America and the Atlantic Ocean to Central Europe as indicated by modelling. HYSPLIT backward trajectories and meteorological data were applied for interpretation of activity variations of measured radionuclides observed at the site of investigation. 7Be and 212Pb activity concentrations and their ratios were used as tracers of vertical transport of air masses. Fukushima data were compared with the data obtained during the Chernobyl accident and in the post Chernobyl period. The activity concentrations of 131I and 137Cs were found to be by 4 orders of magnitude lower as compared to the Chernobyl accident. The activity ratio of 134Cs/137Cs was around 1 with small variations only. The activity ratio of 238Pu/239,240Pu in the aerosol sample was 1.2, indicating a presence of the spent fuel of different origin than that of the Chernobyl accident. - Highlights: ► Two observed maxima in radionuclide concentrations were related to air mass transport. ► HYSPLIT backward trajectories were applied for data interpretation. ► 7Be and 212Pb were used to study a vertical transport of air masses. ► The 134Cs/137Cs activity ratio was around 1. ► 238Pu/239,240Pu ratio was different from global fallout and Chernobyl accident.

  4. Anthropogenic radionuclides and heavy metals in black poplar tree (Populus nigra l.) bark sampled in one of the residential districts of Kyiv

    International Nuclear Information System (INIS)

    Tree bark is known to be a good alternative biological substrate that can be successfully used in the air pollution monitoring studies, especially in urban and industrialized areas suffering from the severe anthropogenic pressure. In Kyiv black poplar is a widespread tree species, whose bark was used as a biological indicator in our research. The bark samples were collected within one of the residential districts of Kyiv and were subject to comprehensive analysis for the content of stable elements and anthropogenic radionuclides. Thermal and epicadmium NAA in short- and long-term irradiation modes, respectively, were used for the determination of concentrations of up to 40 heavy metals, while gamma spectrometry, alpha spectrometry and radiochemical extraction-ion-exchange techniques were applied to determine137Cs, 90Sr, Pu and Am radioactive isotopes in single bark samples. The analytical data obtained were subject to correlation and factor analysis, which revealed basic air pollution sources in the investigated region. It was shown that no significant correlations exist between radionuclides and any determined stable elements in the analyzed samples. All measured radioactive isotopes turned out to fall into a separate factor, which is believed to present the direct deposition of fuel microparticles from the Chernobyl NPP's Unit 4 from the atmosphere into the substratum during radioactive fallouts in spring 1986. This conclusion was supported by the evaluated isotopic ratios 137Cs/90Sr = 1.1 ± 0.4, 137Cs/239+240Pu = 100 ± 40, 239+240Pu/238Pu = 1.0 ± 0.6, as well as by the observed significant variation of the radionuclide concentrations (e.g. 10 Bq/kg - 1540 Bq/kg for 137Cs, 0.1 Bq/kg - 21 Bq/kg for 238,240Pu), which is believed to reflect a microparticle character of the pollution. The obtained data suggest that re-suspension does not play a significant role in the formation of atmospheric air pollution by radioactive substances in the investigated region

  5. Plutonium distribution and remobilization in sediments of the Rhone River mouth (North-Western Mediterranean); Distribution et remobilisation du plutonium dans les sediments du prodelta du Rhone (Mediterranee nord-occidentale)

    Energy Technology Data Exchange (ETDEWEB)

    Lansard, B

    2004-06-15

    The aim of the present study was to describe the distribution and remobilization of plutonium (Pu) in the sediments off the Rhone river mouth. Most of the {sup 238}Pu and {sup 239,240}Pu isotopes introduced into the Rhone River were discharged by the liquid effluents released from the Marcoule reprocessing plant, located 120 km upstream the river mouth. Due to its high affinity for particles and its long half life, {sup 238}Pu is a promising tracer to follow the dispersion of particulate matter from the Rhone River to the Mediterranean Sea. During the 3 REMORA cruises, sediment samples were specifically collected in the Rhone pro-delta area and more offshore on the whole continental shelf of the Gulf of Lions. The measurements of alpha emitters gave a first detailed spatial distribution of Pu isotope concentrations in surface sediments off the Rhone mouth. Using {sup 137}Cs concentrations and their correlations with Pu isotopes, we were able to give a first estimate of Pu inventories for the sediments of the study area. In 2001, plutonium inventories were estimated to 92 {+-} 7 GBq of {sup 238}Pu and 522 {+-} 44 GBq of {sup 239,240}Pu for an area of 500 km{sup 2} in front of the Rhone River mouth. Roughly, 50 % of these inventories are trapped in an area of 100 km{sup 2} corresponding to the extent of the Rhone pro-delta zone. In spring 2002, an ADCP, with current velocity and wave measurements, was moored off the Rhone River mouth. This unique in situ dataset highlights the major role of South-East swells in the erosion of pro-deltaic sediments and their dispersion to the South-Westward direction. Plutonium remobilization was examined using a new experimental design based on sediment resuspension processes studied within a linear recirculating flume. For Gulf of Lions sediments and for a given hydrodynamic stress, remobilization fluxes raised a maximum of 0.08 Bq.m{sup -2}.h{sup -1} for {sup 238}Pu and 0.64 Bq.m{sup -2}.h{sup -1} for {sup 239,240}Pu. A first

  6. Radionuclide concentrations in vegetation at the Los Alamos National Laboratory in 1998

    Energy Technology Data Exchange (ETDEWEB)

    G. J. Gonzales; P. R. Fresquez; M. A. Mullen; L. Naranjo, Jr.

    2000-03-01

    This report summarizes and evaluates the concentrations of {sup 3}H, {sup 137}Cs, {sup 238}Pu, {sup 239,240}Pu, {sup 241}Am, {sup 90}Sr, and total U in understory and overstory vegetation collected from Los Alamos National Laboratory (LANL), its perimeter, and regional background areas in 1998. Comparisons to conservative toxicity reference value safe limits were also made. The arithmetic mean LANL radionuclide concentrations in understory were 501 pCi L{sup {minus}1} for {sup 3}H, 0.581 pCi ash g{sup {minus}1} for {sup 137}Cs, 0.001 pCi ash g{sup {minus}1} for {sup 238}Pu, 0.008 pCi ash g{sup {minus}1} for {sup 239,240}Pu, 0.007 pCi ash g{sup {minus}1} for {sup 241}Am, 1.46 pCi ash g{sup {minus}1} for {sup 90}Sr, and 0.233 {micro}g ash g{sup {minus}1} for total uranium. The mean LANL radionuclide concentrations in overstory were 463 pCi L{sup {minus}1} for {sup 3}H, 1.51 pCi ash g{sup {minus}1} for {sup 137}Cs, 0.0004 pCi ash g{sup {minus}1} {sup 238}Pu, 0.008 pCi ash g{sup {minus}1} for {sup 239,240}Pu, 0.014 pCi ash g{sup {minus}1} for {sup 241}Am, 1.97 pCi ash g{sup {minus}1} for {sup 90}Sr, and 0.388 {micro}g ash g{sup {minus}1} for total uranium. Concentrations of radionuclides and total U in both understory and overstory vegetation at LANL generally were not statistically higher than in perimeter and regional background vegetation ({alpha} = 0.05). The exceptions were LANL {sup 3}H > perimeter {sup 3}H (understory) and LANL {sup 3}H background {sup 3}H (overstory). All maximum radionuclide concentrations were lower than toxicity reference values. With the exception of total U, the relationship between contaminant concentration in soil vs. vegetation was insignificant ({alpha} = 0.05). Generally, as the concentration of total U in soil decreased, the concentration in vegetation increased. This held true for both understory and overstory and regardless of whether data were separated by general location (LANL, perimeter, and background) or not. There was no

  7. Plutonium distribution and remobilization in sediments of the Rhone River mouth (North-Western Mediterranean)

    International Nuclear Information System (INIS)

    The aim of the present study was to describe the distribution and remobilization of plutonium (Pu) in the sediments off the Rhone river mouth. Most of the 238Pu and 239,240Pu isotopes introduced into the Rhone River were discharged by the liquid effluents released from the Marcoule reprocessing plant, located 120 km upstream the river mouth. Due to its high affinity for particles and its long half life, 238Pu is a promising tracer to follow the dispersion of particulate matter from the Rhone River to the Mediterranean Sea. During the 3 REMORA cruises, sediment samples were specifically collected in the Rhone pro-delta area and more offshore on the whole continental shelf of the Gulf of Lions. The measurements of alpha emitters gave a first detailed spatial distribution of Pu isotope concentrations in surface sediments off the Rhone mouth. Using 137Cs concentrations and their correlations with Pu isotopes, we were able to give a first estimate of Pu inventories for the sediments of the study area. In 2001, plutonium inventories were estimated to 92 ± 7 GBq of 238Pu and 522 ± 44 GBq of 239,240Pu for an area of 500 km2 in front of the Rhone River mouth. Roughly, 50 % of these inventories are trapped in an area of 100 km2 corresponding to the extent of the Rhone pro-delta zone. In spring 2002, an ADCP, with current velocity and wave measurements, was moored off the Rhone River mouth. This unique in situ dataset highlights the major role of South-East swells in the erosion of pro-deltaic sediments and their dispersion to the South-Westward direction. Plutonium remobilization was examined using a new experimental design based on sediment resuspension processes studied within a linear recirculating flume. For Gulf of Lions sediments and for a given hydrodynamic stress, remobilization fluxes raised a maximum of 0.08 Bq.m-2.h-1 for 238Pu and 0.64 Bq.m-2.h-1 for 239,240Pu. A first plutonium budget determined for the study area indicates that at least 85 % of the Pu

  8. 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

  9. New development of advanced superconducting electron cyclotron resonance ion source SECRAL (invited)

    International Nuclear Information System (INIS)

    Superconducting electron cyclotron resonance ion source with advance design in Lanzhou (SECRAL) is an 18-28 GHz fully superconducting electron cyclotron resonance (ECR) ion source dedicated for highly charged heavy ion beam production. SECRAL, with an innovative superconducting magnet structure of solenoid-inside-sextupole and at lower frequency and lower rf power operation, may open a new way for developing compact and reliable high performance superconducting ECR ion source. One of the recent highlights achieved at SECRAL is that some new record beam currents for very high charge states were produced by 18 GHz or 18+14.5 GHz double frequency heating, such as 1 e μA of 129Xe43+, 22 e μA of 209Bi41+, and 1.5 e μA of 209Bi50+. To further enhance the performance of SECRAL, a 24 GHz/7 kW gyrotron microwave generator was installed and SECRAL was tested at 24 GHz. Some promising and exciting results at 24 GHz with new record highly charged ion beam intensities were produced, such as 455 e μA of 129Xe27+ and 152 e μA of 129Xe30+, although the commissioning time was limited within 3-4 weeks and rf power only 3-4 kW. Bremsstrahlung measurements at 24 GHz show that x-ray is much stronger with higher rf frequency, higher rf power. and higher minimum mirror magnetic field (minimum B). Preliminary emittance measurements indicate that SECRAL emittance at 24 GHz is slightly higher that at 18 GHz. SECRAL has been put into routine operation at 18 GHz for heavy ion research facility in Lanzhou (HIRFL) accelerator complex since May 2007. The total operation beam time from SECRAL for HIRFL accelerator has been more than 2000 h, and 129Xe27+, 78Kr19+, 209Bi31+, and 58Ni19+ beams were delivered. All of these new developments, the latest results, and long-term operation for the accelerator have again demonstrated that SECRAL is one of the best in the performance of ECR ion source for highly charged heavy ion beam production. Finally the future development of SECRAL will be

  10. Spent LWR fuel leach tests: Waste Isolation Safety Assessment program

    International Nuclear Information System (INIS)

    Spent light-water-reactor (LWR) fuels with burnups of 54.5, 28 and 9 MWd/kgU were leach-tested in deionized water at 250C. Fuel burnup has no apparent effect on the calculated leach rates based upon the behavior of 137Cs and 239+240Pu. A leach test of 54.5 MWd/kgU spent fuel in synthetic sea brine showed that the cesium-based leach rate is lower in sea brine than in deionized water. A rise in the leach rate was observed after approximately 600 d of cumulative leaching. During the rise, the leach rate for all the measured radionuclides become nearly equal. Evidence suggests that exposure of new surfaces to the leachant may cause the increase. As a result, experimental work to study leaching mechanisms of spent fuel has been initiated. 22 figures

  11. Projections of ENDF/B version V performance for fast and thermal reactors using sensitivity coefficients

    International Nuclear Information System (INIS)

    Proposed reductions to 235U(anti ν) and 235U(n,f) in the fast energy range have significant impact for uranium fueled fast critical assemblies. The long-standing LMFBR 28c/49f calculated overprediction is not resolved by proposed Version 5 cross section modifications for 238U(n,γ) and 239Pu(n,f). The upward evaluation for the 239Pu(n,f)/235U(n,f) ratio improves criticality predictions for Pu fueled fast assemblies. For thermal reactors, changes to the 238U resonance parameters significantly reduce the long-standing 28rho discrepancy. Reduced resonance capture in the 1 eV 240Pu resonsnce has significant implications for LWR fuel cycle studies

  12. Improved radioanalytical method for the simultaneous determination of Th, U, Np, Pu and Am(Cm) on a single TRU column by alpha spectrometry and ICP-MS

    Energy Technology Data Exchange (ETDEWEB)

    Macsik, Z.; Groska, J.; Vajda, N. [RadAnal Ltd., Budapest (Hungary); Vogt, S.; Kim, C.S.; Maddison, A.; Donohye, D. [IAEA, Seibersdorf (Austria). Environmental Sample Lab.; Kis-Benedek, G. [IAEA, Seibersdorf (Austria). Terrestrial Environment Lab.

    2013-05-01

    A radioanalytical method based on the use of a single TRU extraction chromatographic column and selective, on-column oxidation state adjustment of actinides was developed for the determination of Th, U, Np, Pu and Am(Cm) in environmental samples (such as sediment and swipe samples). The procedure of Vajda et al. was further investigated and optimized focusing on the separation of Th, U and Np. The improved method combines two measurement techniques - alpha spectrometry and inductively coupled plasma mass spectrometry (ICP-MS) - which allows to obtain more reliable information on a wider range of isotopes: {sup 228}Th, {sup 230}Th, {sup 232}Th, {sup 234}U, {sup 235}U, ({sup 236}U), {sup 238}U, {sup 237}Np, {sup 238}Pu, {sup 239}Pu, {sup 240}Pu, {sup 241}Pu, {sup 241}Am, {sup 242}Cm, {sup 243}Cm and {sup 244}Cm from one sample. (orig.)

  13. Worldwide fallout of plutonium from nuclear weapons tests

    International Nuclear Information System (INIS)

    Measurements of 238Pu and /sup 239,240/Pu fallout from nuclear weapons tests and the SNAP-9A navigational satellite burnup are presented for the years through 1980. Data abstracted from the literature were taken from the stratosphere, atmosphere, and from deposition and surface soil. Over 7300 data entries are included in the 23 tables. The tables are sorted by medium (stratosphere, atmosphere, and deposition near the surface and soil, nuclide, hemisphere, and longitude going from west to east, and are arranged in chronological order. Latitudes are also provided. Fallout levels in SI units (becquerels), calculated from the original readings, and the references from which the original data were taken are given in the report. The appendix is a map showing the various sites from which data were obtained

  14. Np-237 in peat and lichen in Finland

    DEFF Research Database (Denmark)

    Salminen, S.; Paatero, J.; Roos, Per;

    2009-01-01

    Activity concentrations of 237Np in peat and lichen samples in Finland were determined and contributions from nuclear weapons testing in 1950–1960s and the Chernobyl accident were estimated. 237Np was determined with ICP-MS using 235Np as a tracer. Activity concentrations of 237Np in peat samples...... varied between 1.98 ± 0.05 and 14.1 ± 0.3 mBq/m2. The contribution from the Chernobyl accident to the total 237Np deposition in peat was 0.1–13%, the Chernobyl-derived fraction of total 237Np in peat being much lower than the previously determined corresponding Chernobyl-derived fractions of 239+240Pu...

  15. Interspecies comparison of the metabolism and dosimetry of inhaled mixed oxides of plutonium and uranium

    International Nuclear Information System (INIS)

    Three studies were conducted to provide information on the biological fate, distribution of radiation doses among tissues, and implications for potential health consequences of an inhalation exposure to mixed-oxide nuclear fuel materials. In each study, Fischer-344 rats, beagle dogs, and cynomolgus monkeys inhaled one of three aerosols: 750 degrees C calcined mixed oxides of UO2 and PuO2, 1750 degrees C sintered (U,Pu)O2, or 850 degrees C calcined open-quotes pureclose quotes PuO2. These materials were collected from glove-box enclosures immediately after industrial processing of mixed-oxide fuel materials. Lung retention, tissue distribution, and mode of excretion of 238-240Pu, 241Am, and uranium (when present) were quantified by radiochemical analysis of tissue and excreta samples from animals sacrificed at selected times to 6.5 yr after inhalation exposure

  16. Development of Glovebox Unattended Assay and Monitoring system for JNFL MOX fuel fabrication plant

    International Nuclear Information System (INIS)

    In the Mixed Oxide (MOX) Fuel Fabrication Plant of Japan Nuclear Fuel Limited (JNFL), a glove box unattended assay and monitoring system (GUAM) has been developed. The setting-up process of the main components, a 3He(7.5 atm pressure) neutron detector with an organic moderator (6-cm thick polyethylene) and a data acquisition system on a computer, with optimization procedure for their performance is reported in this paper. Dependence of the detection efficiency on the position of 240Pu (10 and 110 g) situated in GUAM, especially in relation with the glove box wall, was examined using 252Cf-neutron source as a simulator. It is concluded that the overall error of the measurement in GUAM amounts to 7.7% before installing the equipments needed to handle presumed MOX fuels. (S.Ohno)

  17. General characterisation of study area and definition of experimental protocols. WP 1 in the project 'Effect of industrial pollution on the distribution dynamics of radionuclides in boreal understorey ecosystems'

    International Nuclear Information System (INIS)

    The research project EPORA (Effects of Industrial Pollution on the Distribution Dynamics of Radionuclides in Boreal Understorey Ecosystems) is part of the EU Nuclear Fission Safety Programme 1994 - 1998. The main purpose of EPORA is to study the influence of strong chemical pollution on the behaviour of artificial radionuclides (137Cs,90Sr, 239,240Pu) in a northern boreal ecosystem and subsequently to assess the significance of the findings to the radiation exposure of the population in such areas. The present report is a documentation of the selection of study areas based on the assessment of available information on pollution in the Kola Peninsula and Northern Fennoscandia and of sampling and analysing methods. (orig.)

  18. Study on the evaluation method to determine the radioactivity concentration waste generated from post-irradiation examination facilities

    International Nuclear Information System (INIS)

    In order to dispose of the radioactive waste which is generated from post-irradiation examination (PIE) facilities, the common evaluation method of radioactivity in wastes from PIE should be established by the actual data such as radioactivity values and the theoretical calculation. In this study, the radioactivity concentrations of 17 nuclides (H-3, C-14, Co-60, Ni-63, Sr-90, Tc-99, Cs-137, Eu-154, U-234, U-235, U-238, Pu-238, Pu-239, Pu-240, Pu-241, Am-241, Cm-244) in combustible wastes stored in NUCLEAR DEVELOPMENT CORPORATION were measured from 3 samples and the radioactivity was calculated by ORIGEN-2 based on initial contents and operation record of the spent fuel. From the comparison of the obtained data by the radiological measurement with the calculated values, the subject to be solved for establishment of the radioactivity evaluation method for PIE was extracted. (author)

  19. Preparation of isotopes and sources of actinide elements

    International Nuclear Information System (INIS)

    As the C.E.A. possesses no isotopic separation facility, the productions of isotopes of actinide elements are performed: a) by neutron irradiation and chemical treatment of special targets, b) by milking decay products from stocks of aged actinide elements, c) by chemical treatment of alpha active wastes. These productions concern the following isotopes: 233U, 238Pu, 242Pu, 243Cm, 242Cm, 244Cm (a); 228Th, 229Th, 234U, 237U, 239Np, 240Pu, 241Am, 248Cm (b); 237Np, 241Am (c). These isotopes are produced to satisfy French and international needs and are sent to users in various forms: solutions, metals, oxides, fluorides, or in different sources forms. The preparation of the sources represents an important field of activities divided into two parts: 1/Industrial sources: production of large series of different sources, 2/ Scientific sources: production of sources suitable for a specific scientific problem. A large overview of these activities is given

  20. Fission dynamics within time-dependent Hartree-Fock: deformation-induced fission

    CERN Document Server

    Goddard, P M; Rios, A

    2015-01-01

    Background: Nuclear fission is a complex large-amplitude collective decay mode in heavy nuclei. Microscopic density functional studies of fission have previously concentrated on adiabatic approaches based on constrained static calculations ignoring dynamical excitations of the fissioning nucleus, and the daughter products. Purpose: To explore the ability of dynamic mean-field methods to describe fast fission processes beyond the fission barrier, using the nuclide $^{240}$Pu as an example. Methods: Time-dependent Hartree-Fock calculations based on the Skyrme interaction are used to calculate non-adiabatic fission paths, beginning from static constrained Hartree-Fock calculations. The properties of the dynamic states are interpreted in terms of the nature of their collective motion. Fission product properties are compared to data. Results: Parent nuclei constrained to begin dynamic evolution with a deformation less than the fission barrier exhibit giant-resonance-type behaviour. Those beginning just beyond the ...

  1. Design concepts for an analytical chemistry laboratory to support plutonium processing

    International Nuclear Information System (INIS)

    The Idaho National Engineering Laboratory was chosen as the preferred site for the location of the special isotope separation (SIS) production plant. The SIS plant will use the atomic vapor laser isotope separation process to ionize the undesirable isotopes of plutonium (238Pu, 240Pu, and 241Pu) in the metal vapor and separate them electrostatically from the desirable isotope 239Pu. Feed to the plant will be reactor-grade plutonium oxide, and the product will be weapons-grade plutonium metal. The SIS plant uses both pyrochemical and aqueous processes. An analytical laboratory, the Material and Process Control Laboratory (MPCL), was designed for making chemical measurements for process control, material control and accountability, and criticality safety

  2. Design concepts for an analytical chemistry laboratory to support plutonium processing

    Energy Technology Data Exchange (ETDEWEB)

    Wade, M.A.; Treibs, H.A.; Hartenstein, S.D.

    1990-01-01

    The Idaho National Engineering Laboratory was chosen as the preferred site for the location of the special isotope separation (SIS) production plant. The SIS plant will use the atomic vapor laser isotope separation process to ionize the undesirable isotopes of plutonium ([sup 238]Pu, [sup 240]Pu, and [sup 241]Pu) in the metal vapor and separate them electrostatically from the desirable isotope [sup 239]Pu. Feed to the plant will be reactor-grade plutonium oxide, and the product will be weapons-grade plutonium metal. The SIS plant uses both pyrochemical and aqueous processes. An analytical laboratory, the Material and Process Control Laboratory (MPCL), was designed for making chemical measurements for process control, material control and accountability, and criticality safety.

  3. Results of a cleanup and treatment test at the Nevada test site: Evaluation of vacuum removal of Pu-contaminated soil

    International Nuclear Information System (INIS)

    We have conducted experiments to evaluate the effectiveness of removing contaminated soils from the Nevada Test Site with a large truck-mounted vacuum cleaner. Our results show that this method is effective, relatively easy, and safe for equipment operators. With four passes of the truck-mounted vacuum, 92% of the 241Am (and the accompanying 239 + 240Pu) was removed and resuspension rates were reduced by more than 99%. The ecological impact was, however, serious in terms of soil erosion and destruction of small animal habitats. Compared to standard earth-moving techniques, vacuuming permits a significant reduction in the volume of soil collected to achieve the desired level of decontamination, and the volume reduction could result in cost savings for packaging, shipment, and burial. This cost savings would only be realized for projects involving decontamination of the top 5 cm of soil

  4. Vertical distribution of 241Pu in the southern Baltic Sea sediments

    International Nuclear Information System (INIS)

    Highlights: • The unique study on 241Pu in sediments from the southern Baltic Sea was presented. • 241Pu was determined using alpha spectrometry by indirect method. • The biggest amount of 241Pu existed in the surface layers of all analyzed sediments. • The highest 241Pu amount comes from the Chernobyl accident. - Abstract: The vertical distribution of plutonium 241Pu in marine sediments can assist in determining the deposition history and sedimentation process of analyzed regions. In addition, 241Pu/239+240Pu activity ratio could be used as a sensitive fingerprint for radioactive source identification. The present preliminary studies on vertical distribution of 241Pu in sediments from four regions of the southern Baltic Sea are presented. The distribution of 241Pu was not uniform and depended on sediment geomorphology and depth as well as location. The highest concentrations of plutonium were found in the surface layers of all analyzed sediments and originated from the Chernobyl accident

  5. Even–odd effects in prompt emission of spontaneously fissioning even–even Pu isotopes

    Energy Technology Data Exchange (ETDEWEB)

    Tudora, A., E-mail: anabellatudora@hotmail.com [University of Bucharest, Faculty of Physics, Bucharest Magurele, POB MG-11, R-76900 (Romania); Hambsch, F.-J. [EC-JRC Institute for Reference Materials and Measurements (IRMM), Retieseweg 111, B-2440, Geel (Belgium); Giubega, G.; Visan, I. [University of Bucharest, Faculty of Physics, Bucharest Magurele, POB MG-11, R-76900 (Romania)

    2015-01-15

    The available experimental Y(A,TKE) data for {sup 236,238,240,242,244}Pu(SF) together with the Zp model prescription with appropriate parameters allows the investigation of even–odd effects in fragment distributions. The size of the global even–odd effect in Y(Z) is decreasing from {sup 244}Pu(SF) to {sup 236}Pu(SF) confirming the general observation of a decrease of the even–odd effect with the fissility parameter. Charge polarizations (ΔZ) and root-mean squares (rms) as a function of A of {sup 236–244}Pu(SF) were obtained for the first time. In the asymmetric fission region both ΔZ(A) and rms(A) exhibit oscillations with a periodicity of about 5 mass units due to the even–odd effects. The total average charge deviations 〈ΔZ〉 (obtained by averaging ΔZ(A) over the experimental Y(A) distribution) are of about |0.5| for all studied Pu(SF) systems. The comparison of the calculated ΔZ(A) and rms(A) of {sup 240}Pu(SF) with those of {sup 239}Pu(n{sub th},f) reported by Wahl shows an in-phase oscillation with a higher amplitude in the case of {sup 240}Pu(SF), confirming the higher even–odd effect in the case of SF. As in the previously studied cases ({sup 233,235}U(n{sub th},f), {sup 239}Pu(n{sub th},f), {sup 252}Cf(SF)) the even–odd effects in the prompt emission of {sup 236–244}Pu(SF) are mainly due to the Z even–odd effects in fragment distributions and charge polarizations and the N even–odd effects in the average neutron separation energies from fragments 〈Sn〉. The size of the global N even–odd effect in 〈Sn〉 is decreasing with the fissility parameter, being higher for the Pu(SF) systems compared to the previously studied systems. The prompt neutron multiplicities as a function of Z, ν(Z), exhibit sawtooth shapes with a visible staggering for asymmetric fragmentations. The size of the global Z even–odd effect in ν(Z) exhibits a decreasing trend with increasing fissility. The average prompt neutron multiplicities as a

  6. Radionuclide contents in suspended sediments in relation to flood types in the lower Rhone River

    International Nuclear Information System (INIS)

    The aim of this work was to study the influence of watershed heterogeneity on the radionuclide contents of suspended particulate matter (SPM) in a large Mediterranean river. As the Rhone River catchment is characterized by a high climatic and geological heterogeneity, floods can be distinguished according to their geographic origins. Long-term time series of particles associated with radionuclides acquired in the framework of radiological surveillance provide a relevant dataset to investigate the variability of radionuclide contents. The SPM exported during Mediterranean floods differ from other floods as they display higher 238U and 232Th contents and the lowest activity ratio 137Cs/(239+240)Pu; these properties could be related to bedrock type and erosion process characteristics and/or to source term differentiation. (authors)

  7. Background concentrations of radionuclides in soils and river sediments in northern New Mexico, 1974-1986

    Energy Technology Data Exchange (ETDEWEB)

    Purtymun, W.D.; Peters, R.J.; Buhl, T.E.; Maes, M.N.; Brown, F.H.

    1987-11-01

    This report documents the range and the upper limit for background concentrations of radionuclides and radioactivity in soils and river sediments that occur as natural rock-forming minerals and worldwide fallout from atmospheric nuclear weapons tests. Documentation is based on the collection of soil and sediment in northern New Mexico and analyzed for /sup 137/Cs, /sup 238/Pu, /sup 239,240/Pu, /sup 90/Sr, total uranium, gross gamma, and tritium. The data used to establish the statistical range and upper limit of background concentration cover a 9- or 13-year period ending in 1986. The knowledge of background levels is necessary to interpret soil and sediment data collected for the annual environmental surveillance report and other reports relating to radionuclides or radioactivity in soils and sediments. 11 refs., 1 fig., 5 tabs.

  8. Study on geochemical association of plutonium in soil using sequential extraction procedure

    International Nuclear Information System (INIS)

    Three kinds of soil, collected in various places (in northwestern and southeastern Poland and near Chernobyl) were used as a subject of sequential extraction and plutonium distribution study. The modified method of TESSIER was applied to separate readily available, carbonate, organic, Fe/Mn oxide and residual fractions. Plutonium isotope activity in soil as well as in particular separated fractions was determined by means of alpha spectrometry. The method of plutonium separation and purification for alpha-spectrometric measurements was modified according to the chemical properties of the extracted fraction. It was found that the major part (about 90%) of 239,240Pu is bound to organic and Fe/Mn oxide fractions (in uncultivated soil samples of northwestern Poland and Chernobyl). In soil samples coming from river valley (southeastern Poland) almost equal amounts of plutonium are distributed between the available, organic and residual fractions. (author)

  9. 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)

  10. Intercomparison of radionuclide measurements on marine sediment sample IAEA-300

    International Nuclear Information System (INIS)

    The results of an intercomparison exercise on a sediment from Baltic Sea, IAEA-300, designed for the determination of artificial and natural radionuclides' levels, are reported. The data from 159 laboratories representing 51 countries have been evaluated. The following are the recommended values, with confidence intervals, 40K, 60Co, 125Sb, 134Cs, 137Cs, 155Eu, 210Pb, 210Po, 228Ra, 234U, 238U, 239+240Pu and 241Am. Information values for 54Mn, 90Sr, 226Ra, 228Th, 230Th, 232Th, 235U and 238Pu are also reported. All values are given on the reference date of 1 January 1993 and expressed in Bq kg-1 dry weight. (author)

  11. 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)

  12. Atmospheric transport of radionuclides emitted due to wildfires near the Chernobyl Nuclear Power Plant in 2015

    Science.gov (United States)

    Evangeliou, Nikolaos; Zibtsev, Sergey; Myroniuk, Viktor; Zhurba, Marina; Hamburger, Thomas; Stohl, Andreas; Balkanski, Yves; Paugam, Ronan; Mousseau, Timothy A.; Møller, Anders P.; Kireev, Sergey I.

    2016-04-01

    In 2015, two major fires in the Chernobyl Exclusion Zone (CEZ) have caused concerns about the secondary radioactive contamination that might have spread over Europe. The total active burned area was estimated to be about 15,000 hectares, of which 9000 hectares burned in April and 6000 hectares in August. The present paper aims to assess, for the first time, the transport and impact of these fires over Europe. For this reason, direct observations of the prevailing deposition levels of 137Cs and 90Sr, 238Pu, 239Pu, 240Pu and 241Am in the CEZ were processed together with burned area estimates. Based on literature reports, we made the conservative assumption that 20% of the deposited labile radionuclides 137Cs and 90Sr, and 10% of the more refractory 238Pu, 239Pu, 240Pu and 241Am, were resuspended by the fires. We estimate that about 10.9 TBq of 137Cs, 1.5 TBq of 90Sr, 7.8 GBq of 238Pu, 6.3 GBq of 239Pu, 9.4 GBq of 240Pu and 29.7 GBq of 241Am were released from both fire events. These releases could be classified as of "Level 3" on the relative INES (International Nuclear Events Scale) scale, which corresponds to a serious incident, in which non-lethal deterministic effects are expected from radiation. To simulate the dispersion of the resuspended radionuclides in the atmosphere and their deposition onto the terrestrial environment, we used a Lagrangian dispersion model. Spring fires redistributed radionuclides over the northern and eastern parts of Europe, while the summer fires also affected Central and Southern Europe. The more labile elements escaped more easily from the CEZ and then reached and deposited in areas far from the source, whereas the larger refractory particles were removed more efficiently from the atmosphere and thus did mainly affect the CEZ and its vicinity. For the spring 2015 fires, we estimate that about 80% of 137Cs and 90Sr and about 69% of 238Pu, 239Pu, 240Pu and 241Am were deposited over areas outside the CEZ. 93% of the labile and 97% of

  13. Radiation exposure from anthropogenic actinides in the northern Ukraine

    International Nuclear Information System (INIS)

    As a consequence of the Chernobyl accident, a large area of the northern Ukraine has been contaminated with many different radioactive substances to such an extent that the population hat to be evacuated. Officially, this exclusion still persists today. Meanwhile, people started returning to their dwellings without permission, and they continue living today within the contaminated area. This raises the question of how severe the radiation exposure to the illegal resettlers really is and of whether the restrictions are still justified. Currently, the radiation exposure is mainly being caused by 137Cs and 90Sr. But in the long-term, the influence of the long-living man-made actinoids will become important. In this study, their portion of the contamination of the evacuated area and the resulting contribution to the radiation exposure were examined in detail by considering the situation of the village Khristinovka as an example. For these purposes, many different environmental samples from Khristinovka (e.g. soil, food) have been analysed. The determination of the activity concentration of the actinoids was carried out by α-spectrometric measurements after radiochemical separations. Among the different man-made actinoids, only the nuclides 238Pu, 239Pu, 240Pu and 241Am are of immediate relevance. The most important actinoid is plutonium because of its slow migration in soil. Therefore, the long-living plutonium nuclides will contribute to the radiation exposure even when 90Sr and 137Cs will have decayed nearly completely. The observed deposition densities of (126 ± 7) Bq m-2 239, 240Pu and (38.7 ± 3.4) Bq m-2 238Pu are comparable to the official statements for this area. Thereby it is possible to distinguish between the contributions which originate from Chernobyl and the nuclear weapons fallout by means of the activity ratios between various radionuclides present. The additional annual dose to the general public of Khristinovka caused by man-made actinoids is

  14. In-vitro analysis of the dissolution kinetics and systemic availability of plutonium ingested in the form of 'hot' particles from the Semipalatinsk NTS

    Energy Technology Data Exchange (ETDEWEB)

    Conway, M. [School of Physics, University College Dublin, Belfield, Dublin 4 (Ireland); Leon Vintro, L. [School of Physics, University College Dublin, Belfield, Dublin 4 (Ireland)], E-mail: luis.leon@ucd.ie; Mitchell, P.I. [School of Physics, University College Dublin, Belfield, Dublin 4 (Ireland); Garcia-Tenorio, R.; Jimenez-Ramos, M.C. [Departamento de Fisica, Universidad de Sevilla, 41012 Sevilla (Spain); Burkitbayev, M. [Department of Inorganic Chemistry, Al-Farabi Kazakh National University, Almaty (Kazakhstan); Priest, N.D. [School of Health and Social Sciences, Middlesex University, Queensway, Enfield EN3 4SA (United Kingdom)

    2009-05-15

    In-vitro leaching of radioactive 'hot' particles isolated from soils sampled at the Semipalatinsk Nuclear Test Site has been carried out in order to evaluate the fraction of plutonium activity released into simulated human stomach and small intestine fluids during digestion. Characterisation of the particles (10-100 Bq {sup 239,240}Pu) and investigation of their dissolution kinetics in simulated fluids has been accomplished using a combination of high-resolution alpha-spectrometry, gamma-spectrometry and liquid scintillation counting. The results of these analyses indicate that plutonium transfer across the human gut following the ingestion of 'hot' particles can be up to two orders of magnitude lower than that expected for plutonium in a more soluble form, and show that for areas affected by local fallout, use of published ingestion dose coefficients, together with bulk radionuclide concentrations in soil, may lead to a considerable overestimation of systemic uptake via the ingestion pathway.

  15. Monte Carlo simulation of transfer reactions using extended R-matrix theory picturing surrogate-type WFCF features

    Science.gov (United States)

    Bouland, Olivier H.

    2016-03-01

    This article supplies an overview of issues related to the interpretation of surrogate measurement results for neutron-incident cross section predictions; difficulties that are somehow masked by the historical conversion route based on Weisskopf-Ewing approximation. Our proposal is to handle the various difficulties by using a more rigorous approach relying on Monte Carlo simulation of transfer reactions with extended R-matrix theory. The multiple deficiencies of the historical surrogate treatment are recalled but only one is examined in some details here; meaning the calculation of in-out-going channel Width Fluctuation Correction Factors (WFCF) which behavior witness partly the failure of Niels Bohr's compound nucleus theoretical landmark. Relevant WFCF calculations according to neutron-induced surrogate- and cross section-types as a function of neutron-induced fluctuating energy range [0 - 2.1 MeV] are presented and commented in the case of the 240Pu* and 241Pu* compound nucleus isotopes.

  16. Characterization of the scission point from fission-fragment velocities

    CERN Document Server

    Caamaño, M; Delaune, O; Schmidt, K -H; Schmitt, C; Audouin, L; Bacri, C -O; Benlliure, J; Casarejos, E; Derkx, X; Fernández-Domínguez, B; Gaudefroy, L; Golabek, C; Jurado, B; Lemasson, A; Ramos, D; Rodríguez-Tajes, C; Roger, T; Shrivastava, A

    2015-01-01

    The isotopic-yield distributions and kinematic properties of fragments produced in transfer-induced fission of 240Pu and fusion-induced fission of 250Cf, with 9 MeV and 45 MeV of excitation energy respectively, were measured in inverse kinematics with the spectrometer VAMOS. The kinematic properties of identified fission fragments allow to derive properties of the scission configuration such as the distance between fragments, the total kinetic energy, the neutron multiplicity, the total excitation energy, and, for the first time, the proton- and neutron-number sharing during the emergence of the fragments. These properties of the scission point are studied as functions of the fragment atomic number. The correlation between these observables, gathered in one single experiment and for two different fissioning systems at different excitation energies, give valuable information for the understanding and modeling of the fission process.

  17. Applications of Event-by-Event Fission Modeling with FREYA

    Directory of Open Access Journals (Sweden)

    Vogt R.

    2012-02-01

    Full Text Available The recently developed code FREYA (Fission Reaction Event Yield Algorithm generates large samples of complete fission events, consisting of two receding product nuclei as well as a number of neutrons and photons, all with complete kinematic information. Thus it is possible to calculate arbitrary correlation observables whose behavior may provide unique insight into the fission process. We first discuss the present status of FREYA, which has now been extended to include spontaneous fission. Concentrating on 239Pu(nth,f, 240Pu(sf and 252Cf(sf, we discuss the neutron multiplicity correlations, the dependence of the neutron energy spectrum on the neutron multiplicity, and the relationship between the fragment kinetic energy and the number of neutrons and their energies. We also suggest novel fission observables that could be measured with modern detectors.

  18. Group Constants Generation of the Pseudo Fission Products for Fast Reactor Burnup Calculations

    Science.gov (United States)

    Gil, Choong-Sup; Kim, Do Heon; Chang, Jonghwa

    2005-05-01

    The pseudo fission products for the burnup calculations of the liquid metal fast reactor were generated. The cross-section data and fission product yield data of ENDF/B-VI were used for the pseudo fission product data of U-235, U-238, Pu-239, Pu-240, Pu-241, and Pu-242. The pseudo fission product data can be used with the KAFAX-F22 or -E66, which are the MATXS-format libraries for analyses of the liquid metal fast reactor at KAERI and were distributed through the OECD/NEA. The 80-group MATXS-format libraries of the 172 fission products were generated and the burnup chains for generation of the pseudo fission products were prepared.

  19. In-vitro analysis of the dissolution kinetics and systemic availability of plutonium ingested in the form of 'hot' particles from the Semipalatinsk NTS

    International Nuclear Information System (INIS)

    In-vitro leaching of radioactive 'hot' particles isolated from soils sampled at the Semipalatinsk Nuclear Test Site has been carried out in order to evaluate the fraction of plutonium activity released into simulated human stomach and small intestine fluids during digestion. Characterisation of the particles (10-100 Bq 239,240Pu) and investigation of their dissolution kinetics in simulated fluids has been accomplished using a combination of high-resolution alpha-spectrometry, gamma-spectrometry and liquid scintillation counting. The results of these analyses indicate that plutonium transfer across the human gut following the ingestion of 'hot' particles can be up to two orders of magnitude lower than that expected for plutonium in a more soluble form, and show that for areas affected by local fallout, use of published ingestion dose coefficients, together with bulk radionuclide concentrations in soil, may lead to a considerable overestimation of systemic uptake via the ingestion pathway.

  20. Assessing radiation impact at a protected coastal sand dune site: an intercomparison of models for estimating the radiological exposure of non-human biota

    International Nuclear Information System (INIS)

    This paper presents the application of three publicly available biota dose assessment models (the ERICA Tool, R and D128/SP1a and RESRAD-BIOTA) to an assessment of the Drigg coastal sand dunes. Using measured 90Sr, 99Tc, 137Cs, 238Pu, 239+240Pu and 241Am activity concentrations in sand dune soil, activity concentration and dose rate predictions are made for a range of organisms including amphibians, birds, invertebrates, mammals, reptiles, plants and fungi. Predicted biota activity concentrations are compared to measured data where available. The main source of variability in the model predictions is the transfer parameters used and it is concluded that developing the available transfer databases should be a focus of future research effort. The value of taking an informed user approach to investigate the way in which models may be expected to be applied in practice is highlighted and a strategy for the future development of intercomparison exercises is presented.

  1. Polonium, uranium and plutonium in the southern Baltic ecosystem

    International Nuclear Information System (INIS)

    This paper presents the results of the measurement of polonium, uranium and plutonium alpha radionuclides in seawater and biota of the southern Baltic ecosystem as well as the recognition of their accumulation processes in the trophic chain. Investigation of the polonium 210Po and plutonium 239+240Pu concentrations in Baltic biota revealed that these radionuclides are strongly accumulated by some species. Mean values of the bioconcentration factor (BCF) fell within the range 9x102 to 3.7x104. The Baltic Sea algae, benthic animals and fish concentrated uranium radioisotopes only to a small extent and mean BCF values for this element range from 1 to 55, which is several orders of magnitude lower than that for polonium and plutonium. Moreover, it was found that Baltic fish constitute an important source of polonium 210Po for humans. (author)

  2. Development of a system of programs HAMMER - ORIGEN - 2 system

    International Nuclear Information System (INIS)

    The development of a system of programs (Hamor-2) to calculate precision inventory of LWR reactors is presented. The Hamor-2 code generates with the Hammer-technion code the four (4) energy groupe effective cross section of the actinides: U-235, U-236, U-238, Pu-239, Pu-240, Pu-241, Pu-242. Hamor-2 collapses the four group energy effective cross section to one group energy effective cross section. Hamor-2 calculates with origen-2 the new concentrations for the actinides using the one group energy effective cross section. Two PWR reactors were analised. (HBR, KWO). The discrepancy between the final actinides conentration results calculated by Hamor-2 and the results of measures finded in the references were calculated. That discrepancies have been compared with the discrepancy between : the final actinide concentration results calculated by Origen-2 and some measured results finded in the references. (E.G.)

  3. Multipole strength function of deformed superfluid nuclei made easy

    CERN Document Server

    Stoitsov, M; Nakatsukasa, T; Losa, C; Nazarewicz, W

    2011-01-01

    We present an efficient method for calculating strength functions using the finite amplitude method (FAM) for deformed superfluid heavy nuclei within the framework of the nuclear density functional theory. We demonstrate that FAM reproduces strength functions obtained with the fully self-consistent quasi-particle random-phase approximation (QRPA) at a fraction of computational cost. As a demonstration, we compute the isoscalar and isovector monopole strength for strongly deformed configurations in $^{240}$Pu by considering huge quasi-particle QRPA spaces. Our approach to FAM, based on Broyden's iterative procedure, opens the possibility for large-scale calculations of strength distributions in well-bound and weakly bound nuclei across the nuclear landscape.

  4. Refinement of Pu parent-daughter isotopic and concentration analysis for forensic (dating) purposes

    International Nuclear Information System (INIS)

    Plutonium (Pu) metal samples from an interlaboratory exchange exercise and simulated swipe samples were dated using plutonium-uranium (Pu-U) and plutonium-americium (Pu-Am). Metal data were evaluated for consistency and the swipe data against its source material. Metal ages based on 239Pu versus 235U and 240Pu versus 236U agreed to within a few percent, while the 238Pu-234U and 241Pu-241Am measurements had larger uncertainties. Swipe ages compared favorably with the material's known history. Neptunium (237Np) analyses were examined in the context of the 241Pu-241Am-237Np system to estimate whether Np can provide insights on material from which Am, Np, and U were removed. (author)

  5. Subroutines to Simulate Fission Neutrons for Monte Carlo Transport Codes

    CERN Document Server

    Lestone, J P

    2014-01-01

    Fortran subroutines have been written to simulate the production of fission neutrons from the spontaneous fission of 252Cf and 240Pu, and from the thermal neutron induced fission of 239Pu and 235U. The names of these four subroutines are getnv252, getnv240, getnv239, and getnv235, respectively. These subroutines reproduce measured first, second, and third moments of the neutron multiplicity distributions, measured neutron-fission correlation data for the spontaneous fission of 252Cf, and measured neutron-neutron correlation data for both the spontaneous fission of 252Cf and the thermal neutron induced fission of 235U. The codes presented here can be used to study the possible uses of neutron-neutron correlations in the area of transparency measurements and the uses of neutron-neutron correlations in coincidence neutron imaging.

  6. Advanced alpha spectrum analysis based on the fitting and covariance analysis of dependent variables

    Science.gov (United States)

    Ihantola, S.; Pelikan, A.; Pöllänen, R.; Toivonen, H.

    2011-11-01

    The correct handling of statistical uncertainties is crucial especially when unfolding alpha spectra that contain a low number of counts or overlapping peaks from different nuclides. For this purpose, we have developed a new spectrum analysis software package called ADAM, which performs a full covariance calculus for alpha-particle emitting radionuclides. By analyzing a large number of simulated and measured spectra, the program was proved to give unbiased peak areas and statistically correct uncertainty limits. This applies regardless of the peak areas and the number of unknown parameters during the fitting. In addition, ADAM performs reliable deconvolution for multiplets, which opens the way for the determination of isotope ratios, such as 239Pu/240Pu.

  7. 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

  8. The design and implementation of the AVNG measurement system

    Energy Technology Data Exchange (ETDEWEB)

    Macarthur, Duncan W [Los Alamos National Laboratory; Thron, Jonathan [Los Alamos National Laboratory; Razinkov, Sergey [RFNC-VNIIEF; Livke, Alexander [RFNC-VNIIEF; Kondratov, Sergey [RFNC-VNIIEF

    2010-01-01

    An attribute measurement system (AMS) measures a number of unclassified attributes of potentially classified material. By displaying these unclassified results only as red or green lights, the AMS protects potentially classified information while still generating confidence in the measurement result. The AVNG that we describe is an AMS built by RFNC-VNIIEF in Sarov, Russia. The AVNG detects neutron and gamma radiation signatures and displays the three unclassified attributes of 'plutonium presence,' 'plutonium mass >2 kg,' and 'plutonium isotopic ratio ({sup 240}Pu to {sup 239}Pu) < 0.1.' In this presentation, we will describe the design of the AVNG neutron and gamma detector subsystems, as well as the design of the entire AMS incorporating these detectors. We will also describe the construction of the AVNG and the final design that was demonstrated in June 2009.

  9. Concentrations of radionuclides in reef and lagoon pelagic fish from the Marshall Islands

    International Nuclear Information System (INIS)

    A radiological survey was conducted from September through November of 1978 to assess the concentrations of persistent man-made radionuclides in the terrestrial and marine environments of 11 atolls and 2 islands of the Northern Marshall Islands. The atolls and islands include Rongelap, Utirik, Taka, Bikar, Rongerik, Ailinginae, Likiep, Jemo, Ailuk, Mejet, Wotho, Ujelang and Bikini. Over 4000 terrestrial and marine samples were collected for radionuclide analysis from 76 different islands. Soils, vegetation, indigenous animals, and cistern and groundwater were collected from the islands. Reef fish, pelagic species, clams, lagoon water, and sediments were obtained from the lagoons. A report is given of all available concentration data for 137Cs, 90Sr, /sup 239+240/Pu, 238Pu, 241Am as well as naturally occurring 40K and other gamma emitting radionuclides in tissues and organs of different species of fish collected from the atolls

  10. Transuranium elements. Physico-chemical properties and environmental behavior. Behavior in soils, waters and sediments. Transfer to the aquatic biomass and to vegetals

    International Nuclear Information System (INIS)

    This report outlines the nuclear and physico-chemical properties of transuranians, such as criticity, formation of complexions hydrolysis and polymerization, disproportionation and radiolysis, the knowledge of which will be useful to radioecologists and will make easier the interpretation of results. Then, it reviews the bibliographical data concerning the behavior of transuranians (Np, 238Pu, 239Pu, 240Pu, Am, Cm) in soils and in the aquatic environment, as well as their uptake by plants, and the transfer to the aquatic biomass. Conspectus tables bring together the present day knowledge on: the values of distribution and diffusion coefficients in the soil and sediments, the values of the factors of transfer in aquatic environment (fresh water, sea water, sand, biomass). A discussion about the influence of the different environmental parameters makes it possible to define the fields of experimental research to which the future efforts would have to be devoted

  11. STRONTIUM AND ACTINIDE SEPARATIONS FROM HIGH LEVEL NUCLEAR WASTE SOLUTIONS USING MONOSODIUM TITANATE 1. SIMULANT TESTING

    Energy Technology Data Exchange (ETDEWEB)

    HOBBS, D. T.; BARNES, M. J.; PULMANO, R. L.; MARSHALL, K. M.; EDWARDS, T. B.; BRONIKOWSKI, M. G.; FINK, S. D.

    2005-04-14

    High-level nuclear waste produced from fuel reprocessing operations at the Savannah River Site (SRS) requires pretreatment to remove {sup 137}Cs, {sup 90}Sr and alpha-emitting radionuclides (i.e., actinides) prior to disposal. Separation processes planned at SRS include caustic side solvent extraction, for {sup 137}Cs removal, and ion exchange/sorption of {sup 90}Sr and alpha-emitting radionuclides with an inorganic material, monosodium titanate (MST). The predominant alpha-emitting radionuclides in the highly alkaline waste solutions include plutonium isotopes {sup 238}Pu, {sup 239}Pu and {sup 240}Pu. This paper provides a summary of data acquired to measure the performance of MST to remove strontium and actinides from simulated waste solutions. These tests evaluated the influence of ionic strength, temperature, solution composition and the oxidation state of plutonium.

  12. Fissile and non-fissile element separation in concrete radioactive waste drums using the SIMPHONIE method

    International Nuclear Information System (INIS)

    The simultaneous photon and neutron interrogation experiment (SIMPHONIE) method, applied to radioactive waste drum characterization, has already been treated in [F. Jallu, A. Lyoussi, C. Passard, E. Payan, H. Recroix, G. Nurdin, A. Buisson, J. Allano, Nucl. Instr. and Meth. B 170 (2000) 489]. First experimental results carried out with U and Pu bare samples were presented, that showed the feasibility of quantifying fissile (235U, 239,241Pu, ...) and non-fissile (234,236,238U, 238,240Pu, ...) elements separately in only one measurement, using both active neutron interrogation and induced photofission interrogation techniques simultaneously. This paper presents new experimental results carried out with U samples embedded in a concrete matrix. These results have been obtained using the DGA/ETCA MiniLinatron pulsed linear electron accelerator located at Arcueil, France. Mass detection limits of less than 2 g of matter have been obtained with the preliminary setup used in these experiments

  13. Actinides detection in the Pacific Coast of Mexico; Deteccion de actinidos en el Litoral Pacifico de Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Ordonez R, E.; Almazan T, M. G.; Cruz C, G. J.; Ramirez S, R., E-mail: eduardo.ordonez@inin.gob.mx [ININ, Carretera Mexico-Toluca s/n, 52750 Ocoyoacac, Estado de Mexico (Mexico)

    2013-10-15

    In this work is evaluated the activity of the alpha emitters, uranium and plutonium, in sand samples and seawater coming from diverse points of the Mexican Pacific Coast (Baja California, Jalisco, Colima and Guerrero). The used techniques were: radiochemistry separation and alpha spectrometry, with these techniques could be observed that the sand contains natural uranium and trace quantities of {sup 239}Pu and {sup 240}Pu combinations. The biggest activity in Pu was found in Finisterra, Baja California Sur (0.13 Bq/kg) and the minor (0 Bq/kg) in Miramar, Colima. The relationship between the geographical localization and the Pu activity suggests that while there is more interaction of the site with the oceanic currents, more is the content of Pu in the sands of the coast. (Author)

  14. AFCI-2.0 Library of Neutron Cross Section Covariances

    Energy Technology Data Exchange (ETDEWEB)

    Herman, M.; Herman,M.; Oblozinsky,P.; Mattoon,C.; Pigni,M.; Hoblit,S.; Mughabghab,S.F.; Sonzogni,A.; Talou,P.; Chadwick,M.B.; Hale.G.M.; Kahler,A.C.; Kawano,T.; Little,R.C.; Young,P.G.

    2011-06-26

    Neutron cross section covariance library has been under development by BNL-LANL collaborative effort over the last three years. The primary purpose of the library is to provide covariances for the Advanced Fuel Cycle Initiative (AFCI) data adjustment project, which is focusing on the needs of fast advanced burner reactors. The covariances refer to central values given in the 2006 release of the U.S. neutron evaluated library ENDF/B-VII. The preliminary version (AFCI-2.0beta) has been completed in October 2010 and made available to the users for comments. In the final 2.0 release, covariances for a few materials were updated, in particular new LANL evaluations for {sup 238,240}Pu and {sup 241}Am were adopted. BNL was responsible for covariances for structural materials and fission products, management of the library and coordination of the work, while LANL was in charge of covariances for light nuclei and for actinides.

  15. Dating of a sediment core from Lake Biel (Switzerland) and source characterization of fallout Pu; {sup 210}Pb- und {sup 137}Cs-Datierung eines Sedimentbohrkerns aus dem Bieler See (CH) und Ursprungsbestimmung von Pu-Fallout

    Energy Technology Data Exchange (ETDEWEB)

    Pregler, Anja

    2016-08-01

    A sediment core from Lake Biel was dated by means of the naturally occurring radioactive isotope {sup 210}Pb as well as by the anthropogenic isotope {sup 137}Cs. The latter one can be detected as radioactive fallout of certain events in the sediment layers and accordingly be correlated with a distinct date. A verification of the correlated events is accomplished by particular isotope ratios of the anthropogenic isotopes {sup 238}Pu, {sup 239}Pu and {sup 240}Pu as well as {sup 241}Am as a decay product of the short-lived {sup 241}Pu. Furthermore, the percentage of the total {sup 137}Cs fallout was calculated corresponding to the specific events.

  16. Fission dynamics within time-dependent Hartree-Fock: boost-induced fission

    CERN Document Server

    Goddard, P M; Rios, A

    2015-01-01

    Background: Nuclear fission is a complex large-amplitude collective decay mode in heavy nuclei. Microscopic density functional studies of fission have previously concentrated on adiabatic approaches based on constrained static calculations ignoring dynamical excitations of the fissioning nucleus, and the daughter products. Purpose: To explore the ability of dynamic mean-field methods to describe induced fission processes, using quadrupole boosts in the nuclide $^{240}$Pu as an example. Methods: Quadrupole constrained Hartree-Fock calculations are used to create a potential energy surface. An isomeric state and a state beyond the second barrier peak are excited by means of instantaneous as well as temporally extended gauge boosts with quadrupole shapes. The subsequent deexcitation is studied in a time-dependent Hartree-Fock simulation, with emphasis on fissioned final states. The corresponding fission fragment mass numbers are studied. Results: In general, the energy deposited by the quadrupole boost is quickl...

  17. The Characterization of Biotic and Abiotic Media Upgradient and Downgradient of the Los Alamos Canyon Weir

    Energy Technology Data Exchange (ETDEWEB)

    P.R. Fresquez

    2006-01-15

    As per the Mitigation Action Plan for the Special Environmental Analysis of the actions taken in response to the Cerro Grande Fire, sediments, vegetation, and small mammals were collected directly up- and downgradient of the Los Alamos Canyon weir, a low-head sediment control structure located on the northeastern boundary of Los Alamos National Laboratory, to determine contaminant impacts, if any. All radionuclides ({sup 3}H, {sup 137}Cs, {sup 238}Pu, {sup 239,240}Pu, {sup 90}Sr, {sup 241}Am, {sup 234}U, {sup 235}U and {sup 238}U) and trace elements (Ag, As, Ba, Be, Cd, Cr, Cu, Hg, Ni, Pb, Sb, Se, and Tl) in these media were low and most were below regional upper level background concentrations (mean plus three sigma). The very few constituents that were above regional background concentrations were far below screening levels (set from State and Federal standards) for the protection of the human food chain and the terrestrial environment.

  18. Assessing radiation impact at a protected coastal sand dune site: an intercomparison of models for estimating the radiological exposure of non-human biota.

    Science.gov (United States)

    Wood, Michael D; Beresford, Nicholas A; Barnett, Catherine L; Copplestone, David; Leah, Richard T

    2009-12-01

    This paper presents the application of three publicly available biota dose assessment models (the ERICA Tool, R&D128/SP1a and RESRAD-BIOTA) to an assessment of the Drigg coastal sand dunes. Using measured (90)Sr, (99)Tc, (137)Cs, (238)Pu, (239+240)Pu and (241)Am activity concentrations in sand dune soil, activity concentration and dose rate predictions are made for a range of organisms including amphibians, birds, invertebrates, mammals, reptiles, plants and fungi. Predicted biota activity concentrations are compared to measured data where available. The main source of variability in the model predictions is the transfer parameters used and it is concluded that developing the available transfer databases should be a focus of future research effort. The value of taking an informed user approach to investigate the way in which models may be expected to be applied in practice is highlighted and a strategy for the future development of intercomparison exercises is presented. PMID:19447531

  19. Actinide-only burnup credit for spent fuel transport

    International Nuclear Information System (INIS)

    A conservative methodology is described that would allow taking credit for burn up in the criticality safety analysis of spent nuclear fuel packages. Requirements for its implementation include isotopic and criticality validation, generation of package loading criteria using limiting parameters, and assembly burn up verification by measurement. The method allows credit for the changes in the 234U, 235U, 236U, 238U, 238Pu, 239Pu, 240Pu, 241Pu, 242Pu, and 241Am concentrations with burnup. No credit for fission product neutron absorbers is taken. Analyses are included regarding the methodology's financial benefits and conservative margin. It is estimated that the proposed actinide-only burnup credit methodology would save 20% of the transport costs. Nevertheless, the methodology includes a substantial margin. Conservatism due to the isotopic correction factors, limiting modelling parameters, limiting axial profiles and exclusion of the fission products ranges from 10 to 25% k. (author)

  20. Fiber optic calorimetry

    Energy Technology Data Exchange (ETDEWEB)

    Rudy, C.; Bayliss, S.; Bracken, D. [Los Alamos National Lab., NM (United States); Bush, J.; Davis, P. [Optiphase, Inc., Van Nuys, CA (United States)

    1998-01-01

    A twin-bridge calorimeter using optical fiber as the sensor element was constructed and tested. This system demonstrates the principle and capability of using fiber for heat-flow measurements of special nuclear material. This calorimeter uses piezoelectric-generated phase-carrier modulation with subsequent electronic signal processing to allow phase shifts as small as 1 microradian ({mu}rad) to be measured. The sensing element consists of 21-m lengths of single-mode optical fiber wrapped around sample and reference chambers. The sensitivity of the calorimeter was determined to be 74 radians (rad) of phase shift per milliwatt of thermal power. One milliwatt of thermal power is equivalent to 400 mg of plutonium (6% {sup 240}Pu). The system noise base was about 0.2 rad, equivalent to about 1 mg of plutonium.

  1. Fiber optic calorimetry

    International Nuclear Information System (INIS)

    A twin-bridge calorimeter using optical fiber as the sensor element was constructed and tested. This system demonstrates the principle and capability of using optical fibers for heat-flow measurements of special nuclear material. This calorimeter uses piezoelectric-generated phase-carrier modulation with subsequent electronic signal processing to allow phase shifts as small as 1 microrad to be measured. The sensing element consists of 21-m lengths of single-mode optical fiber wrapped around sample and reference chambers. The sensitivity of the calorimeter was determined to be 74 rad of phase shift per mW of thermal power. One milliwatt of thermal power is equivalent to 400 mg of plutonium (6% 240Pu). The system noise base was about 0.2 rad, equivalent to about 1 mg of plutonium

  2. Fiber Optic Calorimetry

    International Nuclear Information System (INIS)

    A twin-bridge calorimeter using optical fiber as the sensor element was constructed and tested. This system demonstrates the principle and capability of using optical fibers for heat-flow measurements of special nuclear material. This calorimeter uses piezoelectric-generated phase-carrier modulation with subsequent electronic signal processes to allow phase shifts as small as 1 microradian (microrad) to be measured. The sensing element consists of 21-m lengths of single-mode optical fiber wrapped around sample and reference chambers. The sensitivity of the calorimeter was determined to be 74 radians (rad) of phase shift per milliwatt of thermal power. One milliwatt of thermal power is equivalent to 400 mg of plutonium (6% 240Pu). The system noise base was about 0.2 rad, equivalent to about 1 mg of plutonium

  3. Fiber optic calorimetry

    International Nuclear Information System (INIS)

    A twin-bridge calorimeter using optical fiber as the sensor element was constructed and tested. This system demonstrates the principle and capability of using fiber for heat-flow measurements of special nuclear material. This calorimeter uses piezoelectric-generated phase-carrier modulation with subsequent electronic signal processing to allow phase shifts as small as 1 microradian (μrad) to be measured. The sensing element consists of 21-m lengths of single-mode optical fiber wrapped around sample and reference chambers. The sensitivity of the calorimeter was determined to be 74 radians (rad) of phase shift per milliwatt of thermal power. One milliwatt of thermal power is equivalent to 400 mg of plutonium (6% 240Pu). The system noise base was about 0.2 rad, equivalent to about 1 mg of plutonium

  4. Fiber Optic Calorimetry

    Energy Technology Data Exchange (ETDEWEB)

    Rudy, C.; Bayliss, S.; Bracken, D.; Bush, J.; Davis, P.

    1997-12-12

    A twin-bridge calorimeter using optical fiber as the sensor element was constructed and tested. This system demonstrates the principle and capability of using optical fibers for heat-flow measurements of special nuclear material. This calorimeter uses piezoelectric-generated phase-carrier modulation with subsequent electronic signal processes to allow phase shifts as small as 1 microradian ({micro}rad) to be measured. The sensing element consists of 21-m lengths of single-mode optical fiber wrapped around sample and reference chambers. The sensitivity of the calorimeter was determined to be 74 radians (rad) of phase shift per milliwatt of thermal power. One milliwatt of thermal power is equivalent to 400 mg of plutonium (6% {sup 240}Pu). The system noise base was about 0.2 rad, equivalent to about 1 mg of plutonium.

  5. Fiber optic calorimetry

    Energy Technology Data Exchange (ETDEWEB)

    Rudy, C.R.; Bayliss, S.C.; Bracken, D.S. [Los Alamos National Lab., NM (United States); Bush, I.J.; Davis, P.G. [Optiphase, Inc., Van Nuys, CA (United States)

    1998-12-31

    A twin-bridge calorimeter using optical fiber as the sensor element was constructed and tested. This system demonstrates the principle and capability of using optical fibers for heat-flow measurements of special nuclear material. This calorimeter uses piezoelectric-generated phase-carrier modulation with subsequent electronic signal processing to allow phase shifts as small as 1 {micro}rad to be measured. The sensing element consists of 21-m lengths of single-mode optical fiber wrapped around sample and reference chambers. The sensitivity of the calorimeter was determined to be 74 rad of phase shift per mW of thermal power. One milliwatt of thermal power is equivalent to 400 mg of plutonium (6% {sup 240}Pu). The system noise base was about 0.2 rad, equivalent to about 1 mg of plutonium.

  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. DEVELOPMENT OF AN IMPROVED SODIUM TITANATE FOR THE PRETREATMENT OF HIGH LEVEL NUCLEAR WASTE AT THE SAVANNAH RIVER SITE

    Energy Technology Data Exchange (ETDEWEB)

    Hobbs D. T.; Poirier, M. R.; Barnes, M. J.; Stallings, M. E.; Nyman, M. D.

    2005-11-22

    High-level nuclear waste produced from fuel reprocessing operations at the Savannah River Site (SRS) requires pretreatment to remove {sup 137}Cs, {sup 90}Sr and alpha-emitting radionuclides (i.e., actinides) prior to disposal onsite as low level waste. Separation processes planned at SRS include caustic side solvent extraction, for {sup 137}Cs removal, and sorption of {sup 90}Sr and alpha-emitting radionuclides onto monosodium titanate (MST). The predominant alpha-emitting radionuclides in the highly alkaline waste solutions include plutonium isotopes {sup 238}Pu, {sup 239}Pu and {sup 240}Pu. This paper describes recent results to produce an improved sodium titanate material that exhibits increased removal kinetics and capacity for {sup 90}Sr and alpha-emitting radionuclides compared to the baseline MST material.

  8. LITERATURE REVIEW ON MAXIMUM LOADING OF RADIONUCLIDES ON CRYSTALLINE SILICOTITANATE

    Energy Technology Data Exchange (ETDEWEB)

    Adu-Wusu, K.; Pennebaker, F.

    2010-10-13

    Plans are underway to use small column ion exchange (SCIX) units installed in high-level waste tanks to remove Cs-137 from highly alkaline salt solutions at Savannah River Site. The ion exchange material slated for the SCIX project is engineered or granular crystalline silicotitanate (CST). Information on the maximum loading of radionuclides on CST is needed by Savannah River Remediation for safety evaluations. A literature review has been conducted that culminated in the estimation of the maximum loading of all but one of the radionuclides of interest (Cs-137, Sr-90, Ba-137m, Pu-238, Pu-239, Pu-240, Pu-241, Am-241, and Cm-244). No data was found for Cm-244.

  9. Actinides detection in the Pacific Coast of Mexico

    International Nuclear Information System (INIS)

    In this work is evaluated the activity of the alpha emitters, uranium and plutonium, in sand samples and seawater coming from diverse points of the Mexican Pacific Coast (Baja California, Jalisco, Colima and Guerrero). The used techniques were: radiochemistry separation and alpha spectrometry, with these techniques could be observed that the sand contains natural uranium and trace quantities of 239Pu and 240Pu combinations. The biggest activity in Pu was found in Finisterra, Baja California Sur (0.13 Bq/kg) and the minor (0 Bq/kg) in Miramar, Colima. The relationship between the geographical localization and the Pu activity suggests that while there is more interaction of the site with the oceanic currents, more is the content of Pu in the sands of the coast. (Author)

  10. Application of off/on line sequential injection system with high resolution ICP-MS to measurement radionuclides in environmental samples

    Energy Technology Data Exchange (ETDEWEB)

    Chang-Kyu Kim (IAEA, Physics, Chemistry and Instrumentation Lab., Agency' s Laboratories, Seibersdorf (Austria))

    2010-03-15

    A sequential injection system was developed, which can be widely used for the separation and preconcentration of analytes from diverse environmental samples. The system enables the separation time to be shortened by maintaining a constant flow rate of solution and by avoiding clogging or bubbling in a chromatographic column. The SI system was successfully applied to the separation of 237Np and Pu isotopes in IAEA reference materials and environmental samples, and to the sequential separation of 210Po and 210Pb in a phosphogypsum candidate reference material. The replicate analysis results of 237Np, 239+240Pu 210Po and 210Pb in some IAEA reference materials using the SI system associated with HR-ICP-MS, alpha-spectrometry and LSC are in good agreement with the recommended value within 5% of standard deviation. The SI system enabled a halving of the separation time required for radionuclides. (author)

  11. On the substantion of permissible concentrations of plutonium isotopes in the water of fresh water and sea water NPP cooling reservoirs

    International Nuclear Information System (INIS)

    Substantiation of maximum permissible concentration (PC) of plutonium isotopes (238Pu, 239Pu, 240Pu) in fresh and sea water cooling reservoirs of NPP with fast neutron reactors is given. The main criterion when calculating permissible plutonium content in water of surface reservoirs is the requirement not to exceed the established limits for radiation doses to persons resulted from water use. Data on coefficients of plutonium concentration in sea and fresh water hydrobionts are presented as well as on plutonium PC in water of fresh and sea water cooling reservoirs and bottom sediments of sea water cooling reservoirs. It is shown that doses to critical groups of population doesn't exceed potentially hazardous levels due to plutonium intake through food chains. But the calculation being carried out further should be corrected

  12. Manmade radionuclide vector in Austrian soil and vegetation near Temelin nuclear power plant

    Energy Technology Data Exchange (ETDEWEB)

    Sinojmeri, M.; Ringer, V. [Oesterreichische Agentur fuer Gesundheit und Ernaehrungssicherheit - AGES (Austria)

    2014-07-01

    Since Chernobyl NPP accident an environmental monitoring program concerning the Upper Austrian region near Czech Republic Nuclear Power Plant, NPP Temelin, is in progress between AGES and BMLFUV, the Austrian Federal Ministry of Agriculture, Forestry, Environment, Water and Food, in Austria. This paper presents the results obtained during the sampling campaign over biennial period of 2010-2011. Soil samples, grass and different cereal species were collected. Beside Cs-134, Cs-137 and Sr-89, Sr-90 isotopes, at this phase the number of isotopes determined was extended with plutonium isotopes Pu-238, Pu-239, Pu-240, Pu-241 and Am-241. A comparison of these results with the existing data so far is presented. New knowledge was obtained related the bio-kinetic parameters of these elements in the environment. Document available in abstract form only. (authors)

  13. Preconcentration of trace environmental plutonium from iron oxide matrix using DIPEX® extractant

    International Nuclear Information System (INIS)

    This paper summarizes a new method for preconcentration of rusty metal samples using DIPEX® Actinide Resin from Eichrom Technologies prior to analysis for trace environmental actinides. This method allows for preconcentration of actinides for which the existing lanthanum coprecipitation method is ill-suited. The new and existing methods were shown to provide comparable results for plutonium analysis. Performance was compared for both lab-prepared controls and environmental samples. Using actinide resin, a mean 238Pu activity of 46 ± 13 % mBq (2σ) was measured, while 238Pu activity of 40 ± 6 % mBq (2σ) was measured using lanthanum coprecipitation. Small quantities of 239+240Pu, likely attributable to fallout, were also detected. (author)

  14. Rare correlated sequences detection with DSSSD detector in a real-time mode at the Dubna gas-filled recoil separator

    CERN Document Server

    Tsyganov, Yury

    2016-01-01

    Method of active correlations is a key one to suppress radically beam associated backgrounds in heavy ion induced complete fusion nuclear reactions. This property is enhanced significantly when applying DSSSD detector instead of position sensitive resistive strip detector. Example of application in the 240Pu+48Ca->114+3n reaction is presented. An edge effect between neighbor strips is considered too. The value of the mentioned effect is measured as 15.9 percents for ER-alpha correlation chains. C++ Builder GFS2016 program package for spectral analysis is presented. Calibration parameters (totally 352) were obtained from natYb+48Ca nuclear reaction. New ultra intense FLNR DC280 cyclotron that is expected to be put into operation in the nearest future is also discussed from the viewpoint of the described method developments.

  15. Transport of fallout radiocesium and plutonium in forest soils

    International Nuclear Information System (INIS)

    At five sites in a spruce stand and in a pine stand the vertical activity distributions were determined for sup239+240 Pu and sup137 Cs from the global fallout of weapon testing in the sixties as well as separately for Chernobyl-derived radiocesium. To evaluate the migration rates of these radionuclides in the various soil horinzons, a compartmental model was employed. The migration rates were smallest at the top of the mineral horizon, but increased again with increasing depth. In contrast, the mobility of Chernobyl-derived sup137 Cs is presently in all soil layers significantly higher, but decreases with time. The fixation of radiocesium by the clay particles of the soil is, therefore, a rather slow process

  16. Further investigations of plutonium in aquatic biota of the Great Miami River Watershed including the canal and ponds in Miamisburg, Ohio

    International Nuclear Information System (INIS)

    Results are reported from a preliminary investigation of Pu in aquatic organisms of the Great Miami River Watershed, Ohio. Data are presented on the Pu content of aquatic biota from the canal and ponds located adjacent to the Mound Laboratory. These areas have elevated levels of 238Pu in the water and sediments as the result of a past incident. Radiochemical analysis of biota sampled both upstream and downstream from the effluent pipe of Mound Laboratory showed that plants collected downstream of the laboratory concentrate more 238Pu than the plants located upstream by two to three orders of magnitude. Activities of 238Pu in background samples are unexpectedly high and may be attributed to contamination. Activities of fallout 239,240Pu in the plants from upstream and downstream were approximately the same

  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. Final report on the Risoe monitoring programme after the Chernobyl accident for the period Oct 1, 1986 - Sept 30, 1987

    International Nuclear Information System (INIS)

    In cooperation with the National Agency of Environmental Protection in Denmark, Risoe National Laboratory has examined the radioactive contamination from the Chernobyl accident. The programme for these investigations was an expansion of the countrywide monitoring programme operated since 1962 by Risoe National Laboratory. The present report cover the period Oct 1, 1986 to Sept. 30, 1987. All types of environmental samples relevant for radioactive contamination has been analysed. Most samples were collected countrywide and all samples were analysed for radiocaesium (134Cs and 137Cs). Many samples were furthermore anlaysed for 90Sr and in a few samples transuranic elements (29,240Pu, 241Am and 242Cm) were determined. On the basis of the diet and wholebody measurements of radiocaesium the individual mean dose equivalent commitment from Danish diet consumed in the first two years after the Chernobyl accident was calculated to 27 μ Sv. (author)

  19. Linearly increasing radius of the light fragment during the spontaneous fission of $^{282}$Cn

    CERN Document Server

    Poenaru, D N

    2016-01-01

    In a previous article published in Phys. Rev. C 94 (2016) 014309 we have shown for the first time that the best dynamical trajectory during the deformation toward fission of the superheavy nucleus $^{286}$Fl is a linearly increasing radius of the light fragment, $R_2$. This macroscopic-microscopic result reminds us about the $\\alpha $ or cluster preformation at the nuclear surface, assumed already in 1928, and proved microscopically many times. This time we give more detailed arguments for the neighboring nucleus $^{282}$Cn. Also similar figures are presented for heavy nuclei $^{240}$Pu and $^{252}$Cf. The deep minimum of total deformation energy near the surface is shown for the first time as a strong argument for cluster preformation.

  20. Coordinate-Space Solver for Superfluid Many-Fermion Systems with Shifted Conjugate Orthogonal Conjugate Gradient Method

    CERN Document Server

    Jin, Shi; Roche, Kenneth; Wlazłowski, Gabriel

    2016-01-01

    Self-consistent approaches to superfluid many-fermion systems in 3-dimensions (and subsequent time-dependent approaches) require a large number of diagonalizations of very large dimension hermitian matrices, which results in enormous computational costs. We present an approach based on the shifted conjugate-orthogonal conjugate-gradient (COCG) method for the evaluation of the Green's function, from which we subsequently extract various densities (particle number, spin, current, kinetic energy, etc.) of a nuclear system needed in self-consistent approaches. The approach eschews the construction of the quasiparticle wavefunctions and their corresponding quasiparticle energies, which are never explicitly needed in any density functional approaches. As benchmarks we present calculations for nuclei with axial symmetry, including the ground state of spherical (magic or semi-magic) and axially deformed nuclei, the saddle-point in the $^{240}$Pu constrained fission path, and a vortex in the neutron star crust.