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Sample records for 95zr 103ru 106ru

  1. Studies of quadrupole collectivity in the {gamma}-soft {sup 106}Ru

    Sanchez-Vega, M.; Taylor, R.B.E.; Fogelberg, B.; Lindroth, A. [Uppsala University, Department of Nuclear and Particle Physics, P.O. Box 535, Uppsala (Sweden); Mach, H. [Uppsala University, Department of Nuclear and Particle Physics, P.O. Box 535, Uppsala (Sweden); University of Notre Dame, Institute for Structure and Nuclear Astrophysics, Notre Dame, IN (United States); Aas, A.J. [University of Oslo, Department of Chemistry, P.O. Box 1033, Blindern (Norway); Dendooven, P.; Honkanen, A.; Huhta, M.; Lhersonneau, G.; Oinonen, M.; Parmonen, J.M.; Penttilae, H.; Aeystoe, J. [University of Jyvaeskylae, Department of Physics, P.O. Box 35, Jyvaeskylae (Finland); Persson, J.R. [University of Birmingham, School of Physics and Space Research, Birmingham (United Kingdom); Kurpeta, J. [University of Warsaw, Faculty of Physics, Warsaw (Poland)

    2008-02-15

    Various alternative models were used to describe the structure of {sup 106}Ru. For example, the General Collective Model (GCM) predicts shape-coexistence for {sup 106}Ru with a spherical and a triaxial minimum and strongly mixed structures, while in the IBA-2 calculations, where {sup 106}Ru was considered as transitional from vibrational U(5) to {gamma}-soft O(6), no need was found to include the shape-coexisting configurations. In order to provide additional constraints on the model interpretations, we have applied the Advanced Time-Delayed (ATD) {beta}{gamma}{gamma}(t) method to measure the level lifetimes of the excited levels in {sup 106}Ru. The new results include the half-lives of T{sub 1/2}=183(3) ps and 7.5(30) ps for the 2{sup +}{sub 1} and 2{sup +}{sub 2} states, respectively. (orig.)

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

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

    2015-07-01

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

  3. Retention and excretion of 95Zr-95Nb in humans.

    Thind, K S

    1995-12-01

    This note describes the retention and excretion of 95Zr-95Nb in humans based on a recent CANDU experience and a literature survey of reported cases. Two data bases, QUEST and INIS were used for the survey. Three reported cases were discovered: two for occupational exposures and one for public exposure from nuclear weapons fallout. Human lung retention from these three cases, plus whole body retention and some limited fecal excretion data from a recently occurred exposure at a CANDU station, were reviewed and tested against predictions based on ICRP Publication 30 model. Based on the fits of this model to the reported data it seems that the three occupational exposures exhibit class Y behavior while the public exposure exhibits class W behavior. For only one case is the chemical compound known with certainty: ZrO2. Zirconium oxides are currently classified as class W in ICRP Publications 30 and 54. This work confirms a suggestion that oxides of zirconium be classified as class Y and should be taken into account by the ICRP in its future publications.

  4. Standardization of (106)Ru/Rh by live-timed anticoincidence counting and gamma emission determination.

    da Silva, C J; Rezende, E A; Poledna, R; Tauhata, L; Iwahara, A; Lopes, R T

    2017-04-01

    The absolute activity standardization measurement system of radionuclide by live-timed anticoincidence counting was implemented at LNMRI in 2008 to reduce the effects of some correction factors on the determination of activity with coincidence counting technique used for decades in the laboratory, for example, the corrections of dead time and resolution. With the live-timed anticoincidence system, the variety of radionuclides that can be calibrated by LNMRI was increased in relation to the type of decay. The objective of this study was to standardize the (106)Ru activity, determine gamma emission probabilities by spectrometric method for some energies, and estimate measurement uncertainties.

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

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

    1990-03-01

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

  6. [Dynamics of 95Zr in simulated marine water-sediment-organisms system].

    Wang, Chunlin; Shi, Jianjun; Sun, Pingyue; Li, Mingyun

    2003-06-01

    To provide scientific evidence to evaluate the behavior of 95Zr in ocean ecosystem, the dynamic model of the transference, accumulation and disappearance of 95Zr among the simulated marine water, sediment and organisms was investigated using Nassarius semiplicatus and Boleophthalums pectinirostris as experimental stuffs. The result showed that 95Zr(Bq.g-1 or Bq.ml-1) in the marine water was decreased more than 90% in the first 4 h, and then descended gradually. 95Zr in sediment was increased in the peak in 48 h and then declined. The radioactivity percent of 95Zr in the shell and muslce of Nassarius semiplicatus was 68.7% and 31.30% respectively, while the radioactivity percent was 22.80%, 12.64%, 34.82%, 10.31%, 4.48%, 11.55% and 3.71%, respectively in the fill, fin, viscera, skull, skin, vertebra and muscle of Boleophthalmus pectinirostris. Nassarius semiplicatus had a greater concentrating capability of 95Zr than Boleophthalmus pectinirostris. The order of the 95Zr concentration was found to be sediment > Nassarius semiplicatus > water > Boleophthalmus pectinirostris. A dynamic model of closed four-compartment was constructed with exponent function.

  7. Estimates of relative doses of {sup 106}Ru/{sup 106}Rh of spherical applicators used in ophthalmic brachytherapy; Estimativas de doses relativas de aplicadores esfericos de {sup 106}Ru/{sup 106}Rh usados em braquiterapia oftalmologica

    Paiva, Eduardo de, E-mail: edup2112@gmail.com, E-mail: epaiva@ird.gov.br [Instituto de Radioprotecao e Dosimetria (IRD/CNEN-RJ), Rio de Janeiro, RJ (Brazil). Div. de Fisica Medica

    2016-11-01

    Spherical ophthalmic applicators containing the beta emitter {sup 106}Ru / {sup 106}Rh are much used in brachytherapy for the treatment of various eye diseases. However, there is great difficulty in dosimetry these sources because of its geometric shape, the short range of the beta particles and the large dose gradient, and because of that calculation methods of dose distributions around these sources take on a great importance. In this work an analytical / numerical method is used to estimate the dose rates for a function of depth for spherical sources containing {sup 106}Ru / {sup 106}Rh. The results of the doses on along the central axis for applicators models CXS, CCX, CCY, CCZ, CCD and CGD and CCC are compared with published values calculated by Monte Carlo simulation and measurement results.

  8. 134Cs: 137Cs and 106Ru: 137Cs ratios in intertidal sediments from the Cumbria and Lancashire coasts England

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

    1981-10-01

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

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

    Nilseia Aparecida Barbosa

    2014-08-01

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

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

    Vray, F.

    1994-11-24

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

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

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

    2009-07-01

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

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

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

    2015-10-15

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

  13. Study of Relationship Between Neutron Energy and Fission Yields of 95Zr, 140Ba and 147Nd From 235U

    2001-01-01

    This work measures fission yields of 235U induced by neutrons with energy of thermal, 3.0, 5.0, 5.5, 8.0 and 14.8 MeV. The main purpose is to study the relationship between neutron energy and fission fields of 95Zr,140Ba and 147Nd from 235U by measuring the radioactivity of foil with direct gamma spectrometry. The fission yields induced by fast neutrons are get by fast-thermal-ratio method which based on yields from thermal neutrons, yields by thermal neutron are come from absolute measurement. Since fast-thermal-ratio method eliminates uncertainties of gamma intensity, gamma

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

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

    2011-09-15

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

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

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

    2014-07-01

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

  16. Microwave property improvement of Ca[(Li1/3Nb2/3)0.95Zr0.15]O3+δ perovskite by A-site substitution

    Hu, Mingzhe; Xiong, Gang; Ding, Zhao

    2016-04-01

    The crystal structure and microwave dielectric properties of Ca[(Li1/3Nb2/3)0.95Zr0.15]O3+δ ceramic (CLNZ) are tuned by A-site substitution of Sr2+ and Ba2+ ions in the present paper. The tuning effect on the crystal structure is investigated by the X-ray diffraction (XRD) pattern and it illustrates that single phase of orthorhombic perovskite structure is formed, however, minor amount of BaNb2O6-type second phase is also detected in (Ca1-xBax)[(Li1/3Nb2/3)0.95Zr0.15]O3+δ ceramics (CBLNZ) in the range of x ≥ 0.025, while pure perovskite phase is obtained in (Ca1-xSrx)[(Li1/3Nb2/3)0.95Zr0.15]O3+δ ceramics (CSLNZ) in the whole investigation range of 0 ≤ x ≤ 0.2. With the increase of x value, the unit cell volumes of both CBLNZ and CSLNZ perovskites gradually expand, which results in the degradation of the vibration bond strength between the B-site ions and oxygen in the perovskites. The microscopic structure related thermal parameters in CSLNZ and CBLNZ perovskites are analyzed in terms of Clausius-Mossotti equation to reveal the original contributors in the temperature coefficients. The results show that both Sr2+ and Ba2+ substitution can effectively improve the permittivity and Qf value, especially, improve the temperature coefficient of CLNZ ceramic in a certain range.

  17. Preparation and characterization of Ce{sub 0.95}Zr{sub 0.05}O{sub 2} nanopowders obtained by sol-gel and template methods

    Isasi, J., E-mail: isasi@quim.ucm.es [Departamento de Quimica Inorganica I, Facultad de Ciencias Quimicas, Universidad Complutense de Madrid, Ciudad Universitaria s/n, 28040 Madrid (Spain); Perez, M. [Departamento de Quimica Inorganica I, Facultad de Ciencias Quimicas, Universidad Complutense de Madrid, Ciudad Universitaria s/n, 28040 Madrid (Spain); Castillo, J.F. [Departamento de Quimica Fisica I, Facultad de Ciencias Quimicas, Universidad Complutense de Madrid, Ciudad Universitaria s/n, 28040 Madrid (Spain); Correcher, V. [CIEMAT, Av. Complutense 22, 28040 Madrid (Spain); Aldama, I.; Arevalo, P.; Carbajo, M.C. [Departamento de Quimica Inorganica I, Facultad de Ciencias Quimicas, Universidad Complutense de Madrid, Ciudad Universitaria s/n, 28040 Madrid (Spain)

    2012-09-14

    Ce{sub 0.95}Zr{sub 0.05}O{sub 2} nanopowders have been prepared by a standard Pechini-type sol-gel process and by using polymethyl methacrylate (PMMA) colloidal crystals as template. The effects of these different synthesis routes, on the structure and microstructural features of the nanopowders, were evaluated by using X-ray diffraction (XRD), scanning electron microscopy (SEM) and specific surface area measurements. For both preparation routes, the XRD analysis has shown that a cubic fluorite structure is formed with a crystallite size of {approx}45-50 nm. The SEM images indicate that the powder obtained by the sol-gel Pechini-type process, is constituted by aggregated nanoparticles with relatively uniform shape and size, whereas the powder synthesized as inverse opal exhibits the formation of macropores with a mean size of {approx}130 nm. The specific surface areas of the powder samples obtained by the Pechini-type sol-gel and inverse opal methods are {approx}56 m{sup 2} g{sup -1} and {approx}90 m{sup 2} g{sup -1} respectively. Additionally, the thermoluminescence (TL) signal of the synthetized samples has been measured in order to examine its potential application in the field of dosimetry of ionizing radiations. -- Highlights: Black-Right-Pointing-Pointer Ce{sub 0.95}Zr{sub 0.05}O{sub 2} nanopowders synthesized by sol-gel and template methods. Black-Right-Pointing-Pointer Influence of the synthesis method on structural and microstructural features. Black-Right-Pointing-Pointer Analysis of the thermoluminescence response. Black-Right-Pointing-Pointer Study of application on dosimetry field.

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

    Hardy, E.P. Jr.

    1976-07-01

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

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

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

    2012-12-01

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

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

    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).

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

    American Society for Testing and Materials. Philadelphia

    2005-01-01

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

  2. Accumulation history of radionuclides in the lichen Stereocaulon vesuvianum from Mt. Vesuvius (south Italy).

    Adamo, P; Arienzo, M; Pugliese, M; Roca, V; Violante, P

    2004-01-01

    The fruticose lichen Stereocaulon vesuvianum, growing on the slopes of Mt. Vesuvius (south Italy), was used as a biomonitor of 134Cs, 137Cs, 103Ru and 106Ru derived from the April 26 1986 Chernobyl nuclear reactor accident. Samples were taken at five different quotes (370, 490, 580, 780 and 960 m a.s.l.) and four successive dates (October 1986, December 1986, October 1987 and May 1999). At the first sampling, the concentrations (as Bq kg(-1) dry weight) ranged between 460 and 1020 for 134Cs, 1330 and 2500 for 137Cs, 90 and 200 for 103Ru and 360 and 710 for 106Ru, values generally lower in respect to those measured in soil and higher plants. Of the total 137Cs measured only 14% was due to 1950s and 1960s nuclear weapons tests fallout. Highest average activities of all nuclides were observed at the quote of 960 m and significant correlation (0.7lichen thallus was still appreciable (270-570 Bq kg(-1) dw). Experimental results from the first three samplings yield effective residence time of 0.98+/-0.07, 5.9+/-0.3 and 1.6+/-0.1 years for 106Ru, 137Cs and 134Cs, respectively. The last sampling of May 1999 allowed to achieve a more precise determination of lifetime of 137Cs (6.1+/-0.4 years).

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

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

    2014-07-01

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

  4. Chernobyl radioactivity in surface air over Washington D. C

    Faller, S.H.; Kuroda, P.K. (Environmental Protection Agency, Las Vegas, NV (USA). Environmental Monitoring Systems Lab.); Krask, D.J. (District of Columbia Dept. of Consumer, and Regulatory Affairs, Washington, DC (USA). Air Monitoring Section)

    1991-01-01

    Concentrations of Chernobyl-derived radionuclides in airborne particulate matter over Washington D.C. have been determined by gamma-ray analysis of air filter samples collected during the months of May, June, and July 1986. The results indicate that long-lived nuclides were present in levels comparable to those measured previously at other eastern locations. Extensive washout of radioactivity occurred apparently as a result of heavy rainfall on May 20, and was followed by the arrival of airborne debris with elevated {sup 103}Ru/{sup 137}Cs and {sup 106}Ru/{sup 137}Cs activity ratios. (orig.).

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

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

    1982-04-01

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

  6. Development of analytical methods and survey of radioactive contamination of foodstuffs

    Lee, W. N.; Lee, C. W.; Choi, G. S.; Chung, G. H.; Kang, M. J.; Kim, H. R.; Park, D. W.; Choi, C. S.; Kwak, J. H.; Kwak, S. Y.

    2008-11-15

    After the Chernobyl nuclear accident in 1986, a survey of the radioactive contamination for foodstuffs have been investigated by many countries such as EU, Japan, USA. Concerns about the radioactive contamination of foodstuffs are increased because of the recently special situation (Nuclear test of North Korea). Recently, CODEX added and departmentalised new monitoring radionuclides including alpha and beta radionuclides. The purpose and scope of this study is 1) the development of analysis method for gamma emitting radionuclides({sup 60}Co, {sup 103}Ru, {sup 106}Ru, {sup 144}Ce, {sup 192}Ir) and tritium radionuclides added at new CODEX version. 2) survey and analysis of radioactive contamination for foodstuffs collected from the open markets (the imported and domestic products including North Korea products). Based on deeply examination of the various international standard procedures, the new method for analyzing gamma emitting radionuclides({sup 60}Co, {sup 103}Ru, {sup 106}Ru, {sup 144}Ce, {sup 192}Ir) was developed and applied to radioactive analysis of the foodstuffs. 200 foodstuffs were analyzed(150 imported foodstuffs including 11 samples of North Korea product and 50 domestic foodstuffs). The 137Cs radionuclide among the regulation radionuclides({sup 137}Cs, {sup 134}Cs, {sup 131}I) of the Korea food code and the added radionuclides({sup 60}Co, {sup 103}Ru, {sup 106}Ru, {sup 144}Ce, {sup 192}Ir) at new CODEX version is only detected in the imported foodstuffs but its level is far below the maximum permitted level. This study also developed analytical methods for additional radionuclides(3H) of CODEX. In the normal case, it will be enough only to survey the radioactive contamination for foodstuffs using the regulation radionuclides ({sup 137}Cs, {sup 134}Cs, {sup 131}I) of the Korea food code without the analysis of the added radionuclides at new CODEX version. However, when the radioactivity more than the regulation level is measured, the added

  7. Analysis of a uranium solution for evaluating the total number of fissions in the JCO criticality accident in Tokai-mura.

    Uchiyama, G; Watanabe, K; Miyauchi, M; Togashi, Y; Nakahara, Y; Fukaya, H; Inagawa, J; Suzuki, D; Sonoda, T; Kohno, N; Gunji, K; Ito, M; Sato, T

    2001-09-01

    The uranium solution in the precipitation tank in the JCO's uranium conversion facility was analyzed in order to evaluate the total number of fissions in the criticality accident. Two analytical groups at JAERI performed chemical analyses independently in order to check the validity of the results: the concentration of the fission products (95Zr, 99Mo, 103Ru, 131I, 140Ba, etc), uranium, boron and impurity elements in the solution. The analytical results obtained by the two groups were almost in agreement within the analytical error. The number of fissions per one gram of uranium in the accident was determined to be (1.5 +/- 0.1 ) x 10(14). Also, the total number of events was evaluated to be (2.5 +/- 0.1) x 10(18) fissions using the total amount of uranium (16.6 kg) fed into the precipitation tank at the accident.

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

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

    2014-07-01

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

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

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

    1983-03-01

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

  10. [Influence of nuclear reactor accident at Chernobyl' on the environmental radioactivity in Toyama].

    Morita, M; Shoji, M; Honda, T; Sakanoue, M

    1987-06-01

    The environmental radioactivity caused by the reactor accident at Chernobyl' was investigated from May 7 to May 31 of 1986 in Toyama. Measurement of radioactivities in airborne particles, rain water, drinking water, milk, and mugwort are carried out by gamma-ray spectrometry (pure Ge detector; ORTEC GMX-23195). Ten different nuclides (103Ru, 106Ru, 131I, 132Te-I, 134Cs, 136Cs, 137Cs, 140Ba-La) are identified from samples of airborne particles. In the air samples, a maximum radioactivity concentration of each nuclide is observed on 13th May 1986. The time of the reactor shut-down and the flux of thermal neutron at the reactor were calculated from 131I/132I and 137Cs/134Cs ratio. The exposure dose in Toyama by this accident is given as follows: internal exposure; [thyroid] adult-59 microSv, child-140 microSv, baby-130 microSv, [total body] adult-0.2 microSv, child, baby-0.4 microSv, external exposure; 7 microSv, effective dose equivalent; adult-9 microSv, child-12 Sv, baby-11 microSv.

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

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

    1988-08-01

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

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

    Baca G, A

    1997-07-01

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

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

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

    1986-05-01

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

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

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

    1986-05-01

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

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

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

    1986-01-01

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

  16. Specific activity and activity ratios of radionuclides in soil collected about 20 km from the Fukushima Daiichi Nuclear Power Plant: Radionuclide release to the south and southwest.

    Tagami, Keiko; Uchida, Shigeo; Uchihori, Yukio; Ishii, Nobuyoshi; Kitamura, Hisashi; Shirakawa, Yoshiyuki

    2011-10-15

    Soil samples at different depths (0-2, 5-7 and 10-12cm) were collected from J Village, about 20km south of Fukushima Daiichi Nuclear Power Plant (FNPP) to determine their radionuclide specific activities and activity ratios. The concentrations and activity ratios of (131)I, (134, 136, 137)Cs and (129m)Te were obtained, but only trace amounts of (95)Nb, (110m)Ag and (140)La were detected which were too low to provide accurate concentrations. Radionuclides such as (95)Zr, (103, 106)Ru and (140)Ba that were found in Chernobyl fallout, were not found in these soil samples. This suggests that noble gasses and volatile radionuclides predominated in the releases from FNPP to the terrestrial environment. The average activity ratios of (131)I/(137)Cs, (134)Cs/(137)Cs, (136)Cs/(137)Cs and (129m)Te/(137)Cs were 55, 0.90, 0.22 and 4.0 (corrected to March 11, 2011) in the 0-2cm soil samples of April 20 and 28, 2011.

  17. Radioactivity in food crops

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

    1983-05-01

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

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

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

    1988-08-01

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

  19. Study of various decontamination processes for evaporation concentrates; Etude de differents traitements de decontamination sur des concentrats d'evaporation

    Lefillatre, G.; Cudel, Y.; Rodi, L. [Commissariat a l' Energie Atomique, Chusclan (France). Centre de Production de Plutonium de Marcoule

    1968-07-01

    Generally speaking, the evaporation concentrates are in the form of acid solutions of high salt content, about 400 g/l. The specific activity is very variable: from 0.5 mCi/l to many hundreds of Ci/l. Because of the high solubility of these salts, an attempt has been made to render the radio-elements insoluble in the concentrates before their possible coating with bitumen. With this in view, the possibility of fixing them on inorganic products, of precipitating them in the form of insoluble salts, or of adsorbing them on co-precipitates has been considered. In the case of a fixation of radio-elements by natural or synthetic inorganic products with a high absorptive capacity such as clays, diatomaceous earths, synthetic silicates and alumina, 48 products have been tried. Their selective efficiency with respect to {sup 137}Cs, {sup 90}Sr, {sup 106}Ru-Rh, {sup 144}Ce-Pr, {sup 95}Zr-Nb has been determined both with acid concentrates and with neutralized concentrates (precipitation of hydroxides). In the case of the fixation of radio-elements as insoluble salts or their adsorption on co-precipitates, the choice of treatments involved the two most dangerous radio-elements: {sup 137}Cs and {sup 90}Sr. The conventional processing methods were tried. For {sup 90}Sr. calcium carbonate, calcium oxalate, calcium phosphate, strontium phosphate, manganese oxides, barium sulfate. For {sup 137}Cs: the ferrocyanides of nickel, copper, zinc, cobalt and manganese. The technique consists in carrying out the precipitations (hydroxides, specific processes for {sup 90}Sr and {sup 137}Cs) one after the other without separating the precipitates. (authors) [French] D'une facon generale, les concentrats d'evaporation se presentent sous forme de solutions acides de mineralisation elevee, de l'ordre de 400 g/l. Leur activite specifique est tres variable: de 0.5 mCi/l a plusieurs centaines de Ci/l. En raison de la tres grande solubilite de ces sels, il a paru interessant de

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

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

    2010-07-01

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

  1. Airborne Chernobyl radioactivity in College Park, Maryland

    Kitto, M.E. (Dept. of Chemistry, Univ. of Maryland, College Park, MD (USA) New York State Dept. of Health, Wadsworth Center for Laboratories and Research, Albany, NY (USA)); Faller, S.H. (Dept. of Chemistry, Univ. of Maryland, College Park, MD (USA) Environmental Monitoring Systems Lab., U.S. Environmental Protection Agency, Las Vegas, NV (USA)); Anderson, D.L. (Dept. of Chemistry, Univ. of Maryland, College Park, MD (USA) Food and Drug Administration Lab., National Inst. of Standards and Technology, Gaithersburg, MD (USA)); McCarthy, L.E. (Dept. of Chemistry, Univ. of Maryland, College Park, MD (USA) Gerghty and Miller, Inc., Plainview, NY (USA))

    1991-01-01

    Atmospheric concentrations of Chernobyl-derived radionuclides collected on filters in College Park, Maryland during May, 1986 have been determined by gamma-ray analysis. Measurements indicate that following an extensive wash-out of radioactivity, {sup 103}Ru was enriched in the upper atmosphere relative to {sup 137}Cs and {sup 131}I. Absolute concentrations of particulate and gas-phase radionuclides and the observed enrichment of {sup 103}Ru are in agreement with other studies. (orig.).

  2. Ruthenium-103, iodine-131, tellurium-132, and cesium-137 in air after the Chernobyl event

    Liu, C.K.; Faller, S.H.; Kuroda, P.K. (Environmental Protection Agency, Las Vegas, NV (USA). Environmental Monitoring Systems Lab.)

    1990-01-01

    Concentrations of airborne fission products during the month following the Chernobyl event, were analyzed by gamma-ray counting of 283 air filter samples that were collected at 20 different locations in the western United States. While the presence of {sup 103}Ru, {sup 131}I, {sup 134}Cs and {sup 137}Cs was detected in many of the air filter samples, 78.2-hour {sup 132}Te was detected in only 19 samples all from the sampling stations located in the State of Nevada. The results obtained in this study indicate that the release of {sup 131}I from the Chernobyl reactor was roughly 50 percent greater than that of {sup 137}Cs, while the release of {sup 137}Cs was about 8 times that of {sup 103}Ru and 25 percent greater than that of {sup 132}Te. (orig.).

  3. Unusual nuclide concentrations in air after the 1986 Chernobyl event

    Faller, S.H.; Kuroda, P.K. (Environmental Protection Agency, Las Vegas, NV (USA). Environmental Monitoring Systems Lab.)

    1990-01-01

    Concentrations of 1.0-year {sup 106}Ru, 2.8-year {sup 125}Sb, 2.1-year {sup 134}Cs, and 30-year {sup 137}Cs were measured for a total of 39 air filter samples collected at Chico, California, and Reno, Nevada, during the month of May 1986. Radioactive debris in which {sup 106}Ru, {sup 125}Sb, and {sup 134}Cs were enriched relative to {sup 137}Cs reached the west coast of the United States during the first week of May 1986. The air mass that carried this debris seems to have circled the world and reached the west coast for the second time 3 weeks later during the last week of May 1986. Results obtained in this study indicate that the initial release of nuclear debris from the Chernobyl reactor took place in a manner similar to the atmospheric injection of radionuclides from a nuclear weapon's test. (orig.).

  4. Source terms for radioactive gaseous effluents from a model high-level waste solidification facility

    Godbee, H.W.; Kibbey, A.H.

    1976-11-01

    The model high-level waste solidification facility (WSF) is envisaged as being similar to the New Waste Calcining Facility (NWCF) being constructed at the Idaho National Engineering Laboratory but with provisions for incorporating the calcine into a glass. The decontamination factor (DF) is estimated to be one for tritium, 100 for iodine, and 5.0 x 10/sup 8/ for ruthenium. The DFs for other nuclides are in the range of mid to high 10/sup 9/. The volatile radionuclide of primary concern in waste solidification is ruthenium (in particular, /sup 106/Ru). With an estimated DF of 5.0 x 10/sup 8/, the /sup 106/Ru expected to be released from the WSF amounts to 3.4, 2.9, and 0.091 mCi/day for immediate solidification, a freshly filled waste tank (189 days), and five years of tank storage, respectively. The FSAR of the Barnwell Nuclear Fuel Plant Separations Facility implies that 4.6 mCi/day of /sup 106/Ru might be released from the stack of the separations facility and states that such a release meets all state and Federal standards and specifications.

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

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

    2015-11-01

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

  6. Placental transfer of ruthenium in rat and guinea-pig

    Levack, V.M.; Pottinger, H.; Harrison, J.D. [National Radiological Protection Board, Chilton (United Kingdom)

    1994-12-01

    Ruthenium-106 in citrate solution was administered intravenously to rat at different stages of pregnancy and to guinea-pig either before conception or in late pregnancy. The results for rat showed that retention in the embryo/foetus measured at 3-5 days after administration increased from about 0.0002% of injected activity per embryo/foetus on day 12 of gestation to about 0.05% at birth. The relative concentrations of {sup 106}Ru in embryo/foetus and mother (C{sub f}/C{sub m} ratio) were about 0.1 in each case. Concentrations in the yolk sac on day 12 were about 1% g{sup -1} compared with 0.01% g{sup -1} kin the foetus/ Retention in the guinea-pig foetus in late gestation at 7 days after administration (days 50-57) was about 0.2% injected activity per foetus, corresponding to a C{sub f}/C{sub m} = 0.2. Retention in each foetoplacental unit was 2% of injected {sup 106}Ru with 50% in the yolk sac, 35% in the placenta and 10% in the foetus. For administration 4 weeks prior to conception, the level of {sup 106}Ru retained in the foetus on day 57 of gestation was two orders of magnitude lower than after short-term administration, with a C{sub f}/C{sub m} about 0.004. (author).

  7. Determination of Technetium-99 in Environmental Samples by Solvent Extraction at Controlled Valence

    Chen, Q.J.; Aarkrog, A.; Dahlgaard, H.

    1989-01-01

    Distribution coefficients of technetium and ruthenium are determined under different conditions with CCl4, cyclohexanone, and 5% tri-isooctylamine (TIOA)/xylene. A method for analyzing 99Tc in environmental samples has been developed by solvent extraction in which the valences of technetium...... are subsequently separated by solvent extraction with cyclohexanone and 5% TIOA/xylene. The decontamination of the procedure is 1.35 .cntdot. 105 for 103Ru and 1.66 .cntdot. 105 for 110mAg. The chemical yield of technetium-99 is 55%....

  8. Determination of IRT-2M fuel burnup by gamma spectrometry.

    Koleška, Michal; Viererbl, Ladislav; Marek, Milan; Ernest, Jaroslav; Šunka, Michal; Vinš, Miroslav

    2016-01-01

    A spectrometric system was developed for evaluating spent fuel in the LVR-15 research reactor, which employs highly enriched (36%) IRT-2M-type fuel. Such system allows the measurement of detailed fission product profiles. Within these measurements, nuclides such as (137)Cs, (134)Cs, (144)Ce, (106)Ru and (154)Eu may be detected in fuel assemblies with different cooling times varying between 1.67 and 7.53 years. Burnup calculations using the MCNPX Monte Carlo code data showed good agreement with measurements, though some discrepancies were observed in certain regions. These discrepancies are attributed to the evaluation of irradiation history, reactor regulation pattern and buildup schemes.

  9. PMT signal increase using a wavelength shifting paint

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

    2015-01-01

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

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

    Selvam, T Palani; Vandana, S; Bakshi, A K; Babu, D A R

    2016-02-01

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

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

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

    1999-09-30

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

  12. Application of Large Scale GEM for Digital Hadron Calorimetry

    Yu, J; Park, K; Park, S; Sosebee, M; Tran, N; White, A P

    2011-01-01

    The High Energy Physics group of the University of Texas at Arlington Physics Department has been developing Gas Electron Multiplier (GEM) detectors for use as the sensitive gap detector in digital hadron calorimeters (DHCAL) for the future International Linear Collider. In this study, two kinds of prototype GEM detectors have been tested. One has 30x30 cm2 active area double GEM structure with a 3 mm drift gap, a 1 mm transfer gap and a 1 mm induction gap. The other one has two 2x2 cm2 GEM foils in the amplifier stage with a 5 mm drift gap, a 2 mm transfer gap and a 1 mm induction gap. We present characteristics of these detectors obtained using high-energy charged particles, cosmic ray muons and 106Ru and 55Fe radioactive sources. From the 55Fe tests, we observed two well-separated X-ray emission peaks and measured the chamber gain to be over 6500 with a high voltage of 395 V across each GEM electrode. Both the spectra from cosmic rays and the 106Ru fit well to Landau distributions as expected from minimum ...

  13. Measurements of extinct fission products in nuclear bomb debris: Determination of the yield of the Trinity nuclear test 70 y later.

    Hanson, Susan K; Pollington, Anthony D; Waidmann, Christopher R; Kinman, William S; Wende, Allison M; Miller, Jeffrey L; Berger, Jennifer A; Oldham, Warren J; Selby, Hugh D

    2016-07-19

    This paper describes an approach to measuring extinct fission products that would allow for the characterization of a nuclear test at any time. The isotopic composition of molybdenum in five samples of glassy debris from the 1945 Trinity nuclear test has been measured. Nonnatural molybdenum isotopic compositions were observed, reflecting an input from the decay of the short-lived fission products (95)Zr and (97)Zr. By measuring both the perturbation of the (95)Mo/(96)Mo and (97)Mo/(96)Mo isotopic ratios and the total amount of molybdenum in the Trinity nuclear debris samples, it is possible to calculate the original concentrations of the (95)Zr and (97)Zr isotopes formed in the nuclear detonation. Together with a determination of the amount of plutonium in the debris, these measurements of extinct fission products allow for new estimates of the efficiency and yield of the historic Trinity test.

  14. Post-irradiation examinations of a Zr2.5Nb pressure tube of the Karachi nuclear power plant (KANUPP)

    Zaheer, Mohammed Sajjad; Akhtar, Javed Iqbal; Ahmad, Ejaz; Saleem, Muhammad; Hussain, Syed Mukarrum; Qureshi, Masroor Ahmad; Khan, Azmatullah; Ali, Rafaqat; Zafarullah, Muhammad

    1996-09-01

    The results of post-irradiation examinations of a pressure tube of fuel channel No. G-12 of KANUPP have been described. A detailed study was made in Canada by AECL. A parallel investigation on its seven rings of about 50 mm length each was also carried out at PINSTECH. Visual inspection showed normal oxidation effects. Gamma spectrometry showed the presence of 95Zr and 95Nb. Microstructural study revealed the characteristic alpha plus a transformed beta phase structure.

  15. Thermal stability of the C106 dye in robust electrolytes

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

    -MPN) introduced by Gao et al. in 2008. [1]. Figure 1 Thermal degradation of C106 bound to TiO2 at 80 ºC in dark as a function of heating time. ● C106 = RuLL´(NCS)2 ■ RuLL´(NCS)(NBB)+ ▲ RuLL´(NCS)(3-MPN)+ The C106 dye was attached to the surface of TiO2 nano-particles and stable colloidal solutions...... of the particles were prepared in electrolyte mixture B. The solutions were thermally treated at 80 ◦C for 0-2000 hours followed by dye extraction and analysis by HPLC coupled to UV/Vis and electro spray mass spectrometry [2]. Figure 1 shows the concentration profiles of C106 samples prepared under ambient...

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

    Riedler, P; Kaplon, J; Weilhammer, Peter

    2002-01-01

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

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

    孙青苗; 蔡林; 张建中

    2010-01-01

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

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

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

    1998-12-31

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

  19. Results with a micro-cavity plasma panel detector

    NONE

    2015-07-01

    During the three last years, a complete study of a radiation detector based on plasma panel technology (main component of plasma television display) has been completed using source, cosmic ray and beam. This studies showed a fast response (O(5 ns)), high spatial resolution detection of ionizing particle and minimum ionizing particles. It shows very promising results in term of pixel-to-pixel uniformity and time stability of both signal shapes and rates. The prototype has also demonstrated very low background over a wide range of applied high voltages, excellent pixel response isolation, time resolutions of a few nanoseconds, and efficiencies above 95% over a 100-volt range for beta particles emitted by a {sup 106}Ru radioactive source. A full report will be presented (authors)

  20. Comparison between beta radiation dose distribution due to LDR and HDR ocular brachytherapy applicators using GATE Monte Carlo platform.

    Mostafa, Laoues; Rachid, Khelifi; Ahmed, Sidi Moussa

    2016-08-01

    Eye applicators with 90Sr/90Y and 106Ru/106Rh beta-ray sources are generally used in brachytherapy for the treatment of eye diseases as uveal melanoma. Whenever, radiation is used in treatment, dosimetry is essential. However, knowledge of the exact dose distribution is a critical decision-making to the outcome of the treatment. The Monte Carlo technique provides a powerful tool for calculation of the dose and dose distributions which helps to predict and determine the doses from different shapes of various types of eye applicators more accurately. The aim of this work consisted in using the Monte Carlo GATE platform to calculate the 3D dose distribution on a mathematical model of the human eye according to international recommendations. Mathematical models were developed for four ophthalmic applicators, two HDR 90Sr applicators SIA.20 and SIA.6, and two LDR 106Ru applicators, a concave CCB model and a flat CCB model. In present work, considering a heterogeneous eye phantom and the chosen tumor, obtained results with the use of GATE for mean doses distributions in a phantom and according to international recommendations show a discrepancy with respect to those specified by the manufacturers. The QC of dosimetric parameters shows that contrarily to the other applicators, the SIA.20 applicator is consistent with recommendations. The GATE platform show that the SIA.20 applicator present better results, namely the dose delivered to critical structures were lower compared to those obtained for the other applicators, and the SIA.6 applicator, simulated with MCNPX generates higher lens doses than those generated by GATE.

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

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

    2014-07-01

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

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

    Hardy, E.P. Jr.

    1977-07-01

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

  3. Precise explosive force determination of the first A-bomb 70 years after the explosion; Genaue Sprengkraftbestimmung der ersten A-Bombe 70 Jahre nach der Explosion

    Anon.

    2016-11-01

    This short note provides a reference to an American magazine article [Susan K. Hanson et al., Proc. Natl. Acad. Sci. U.S.A. 113, 8104 (2016) - 4933] in which an approach to measuring extinct fission products is described that would allow for the characterization of a nuclear test at any time. The isotopic composition of molybdenum in five samples of glassy debris from the 1945 Trinity nuclear test has been measured. Non-natural molybdenum isotopic compositions were observed, reflecting an input from the decay of the short-lived fission products {sup 95}Zr and {sup 97}Zr. By measuring both the perturbation of the {sup 95}Mo/{sup 96}Mo and {sup 97}Mo/{sup 96}Mo isotopic ratios and the total amount of molybdenum in the Trinity nuclear debris samples, it is possible to calculate the original concentrations of the {sup 95}Zr and {sup 97}Zr isotopes formed in the nuclear detonation. Together with a determination of the amount of plutonium in the debris, these measurements of extinct fission products allow for new estimates of the efficiency and yield of the historic Trinity test.

  4. Validity of microsphere depositions for regional myocardial flows

    Bassingthwaighte, J.B.; Malone, M.A.; Moffett, T.C.; King, R.B.; Little, S.E.; Link, J.M.; Krohn, K.A.

    1987-07-01

    Due to the particulate nature of microspheres, their deposition in small-tissue regions may not be strictly flow dependent. To evaluate the importance of rheological and geometric factors and random error, their deposition densities in small regions of rabbit hearts were examined in comparison with those of a new molecular microsphere, 2-iododesmethylimipramine (IDMI), whose high lipid solubility allows it to be delivered into tissue in proportion to flow, and whose binding in tissue prevents rapid washout. /sup 141/Ce- and /sup 103/Ru-labeled 16.5-..mu..m spheres in one syringe and (/sup 125/I)- and (/sup 131/I)DMI in another syringe were injected simultaneously into the left atrium of open-chest rabbits, while obtaining reference blood samples from the femoral artery. Hearts were removed 1 min after injection, cut into /approximately/ 100 pieces averaging 54 mg, and the regional deposition densities calculated for each tracer from the isotopic counts. Scatter plots of sphere densities vs. IDMI densities showed that differences between microspheres and IDMI had substantial scatter and were not random. Microsphere depositions tended to be lower that IDMI deposition at low flows and higher at high flows. The authors conclude that microspheres are generally adequate for estimating regional flows but suffer systematic error when the regions of interest are supplied via arteries of diameters only a few times those of microspheres.

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

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

    1984-05-01

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

  6. Surrogate formulations for thermal treatment of low-level mixed waste. Part 1: Radiological surrogates

    Stockdale, J.A.D.; Bostick, W.D.; Hoffmann, D.P. [Martin Marietta Energy Systems, Inc., Oak Ridge, TN (United States); Lee, H.T. [Oak Ridge Associated Universities, TN (United States)

    1994-01-01

    The evaluation and comparison of proposed thermal treatment systems for mixed wastes can be expedited by tests in which the radioactive components of the wastes are replaced by surrogate materials chosen to mimic, as far as is possible, the chemical and physical properties of the radioactive materials of concern. In this work, sponsored by the Mixed Waste Integrated Project of the US Department of Energy, the authors have examined reported experience with such surrogates and suggest a simplified standard list of materials for use in tests of thermal treatment systems. The chief radioactive nuclides of concern in the treatment of mixed wastes are {sup 239}Pu, {sup 238}U, {sup 235}U, {sup 137}Cs, {sup 103}Ru, {sup 99}Tc, and {sup 90}Sr. These nuclides are largely by-products of uranium enrichment, reactor fuel reprocessing, and weapons program activities. Cs, Ru, and Sr all have stable isotopes that can be used as perfect surrogates for the radioactive forms. Technetium exists only in radioactive form, as do plutonium and uranium. If one wishes to preclude radioactive contamination of the thermal treatment system under trial burn, surrogate elements must be chosen for these three. For technetium, the authors suggest the use of natural ruthenium, and for both plutonium and uranium, they recommend cerium. The seven radionuclides listed can therefore be simulated by a surrogate package containing stable isotopes of ruthenium, strontium, cesium, and cerium.

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

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

    1992-01-01

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

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

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

    2013-12-01

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

  9. Development of a CMPO based extraction process for partitioning of minor actinides and demonstration with genuine fast reactor fuel solution (155 GWd/Te)

    Antony, M.P.; Kumaresan, R.; Suneesh, A.S. [Indira Gandhi Centre for Atomic Research, Kalpakkam (IN). Fuel Chemistry Div.] (and others)

    2011-07-01

    A method has been developed for partitioning of minor actinides from fast reactor (FR) fuel solution by a TRUEX solvent composed of 0.2 M n-octyl(phenyl)-N,N-diisobutylcarbamoyl-methylphosphine oxide (CMPO)-1.2 M tri-n-butylphosphate (TBP) in n-dodecane (n-DD), and subsequently demonstrated with genuine fast reactor dissolver solution (155 GWd/Te) using a novel 16-stage ejector mixer settler in hot cells. Cesium, plutonium and uranium present in the dissolver solution were removed, prior to minor actinide partitioning, by using ammonium molybdophosphate impregnated XAD-7 (AMP-XAD), methylated poly(4-vinylpyridine) (PVP-Me), and macroporous bifunctional phosphinic acid (MPBPA) resins respectively. Extraction of europium(III) and cerium(III) from simulated and real dissolver solution, and their stripping behavior from loaded organic phase was studied in batch method using various citric acid-nitric acid formulations. Based on these results, partitioning of minor actinides from fast reactor dissolver solution was demonstrated in hot cells. The extraction and stripping profiles of {sup 154}Eu, {sup 144}Ce, {sup 106}Ru and {sup 137}Cs, and mass balance of {sup 241}Am(III) achieved in the demonstration run have been reported in this paper. (orig.)

  10. Chemical and physical considerations of the use of nuclear fuel spikants for deterrence

    Selle, J. E.

    1978-10-01

    One proposed method of inhibiting the diversion of nuclear fuel for clandestine purposes is to add to the fuel a highly gamma-active material of such intensity that remote handling equipment is necessary in all stages of handling and reprocessing. This is called spiking for deterrence. The present work sought to identify candidate spikants and identify potential materials problems that might occur as the result of incorporation of these spikants with the fuel. Potential spikants were identified and thermodynamic analysis was performed to determine their chemical and physical states. Phase relationships between spikants (and their decay products) and the fuel constituents were surveyed. According to criteria defined in this report, /sup 60/Co, /sup 106/Ru, and /sup 144/Ce appear to have the greatest potential as spikants. Cerium should be present as the oxide, soluble in the fuel, while cobalt and ruthenium should be present in the metallic state with very low solubility in the fuel. Experimental work on the distribution of fission products and their interactions with cladding was also surveyed to provide information on the distribution of spikants in the fuel and describe the probable effects of spikants on the fuel. Cobalt, ruthenium, and cerium should not present any problems due to reaction with stainless steel cladding.

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

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

    2007-01-01

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

  12. Participation of the radioanalytical laboratories of CDTN/CNEN in the national intercomparison program for radionuclide analysis in water

    Abreu, Renata D.; Kastner, Geraldo F.; Gomes, Nilton C.; Furtado, Renato C.S.; Amaral, Angela M.; Temba, Eliane S.C.; Andrade, Geraldo V.; Monteiro, Roberto Pellacani G., E-mail: rda@cdtn.br [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil)

    2015-07-01

    This paper reports the performance of the radioanalytical laboratories of Analytical Techniques Service - SERTA/CDTN/CNEN achieved in the National Intercomparison Program - PNI conducted by the Institute of Radiation Protection and Dosimetry - IRD. The program comprehends the distribution of synthetic water samples for some (approximately 25) national laboratories in order to promote analytical credibility and to ensure the reliability of the analytical results based on radiochemical methodologies. In this program water samples are artificially contaminated at environmental level with known amounts of important radionuclides for radiological protection. The parameters and analytes evaluated are, {sup 60}Co, {sup 65}Zn, {sup 106}Ru, {sup 133}Ba, {sup 134}Cs, {sup 137}Cs, {sup 3}H, {sup 90}Sr, {sup 226}Ra, {sup 228}Ra, {sup 210}Pb, U{sub nat}, {sup 232}Th and gross alpha and beta measurements. In the last 13 years our performance was considered 'good' and 'acceptable' in over 90% of the rounds accomplished. (author)

  13. Electrochemical treatment of liquid wastes

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

    1997-10-01

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

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

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

    2015-07-01

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

  15. HGMF model tests for heat carrier cleaning on Leningrad Nuclear Power plant

    Alikhanov, K.R.; Mikhailov, N.N.; Smirnova, M.N.; Cheremnykh, P.A. (I.V. Kurchatov Inst. of Atomic Energy, Moscow (SU)); Kalashnikov, V.V.; Orlov, A.K.; Srelnikov, V.S. (Inst. of Energetic Technology, Leningrad (SU)); Klyuchnikov, B.V.; Sergeev, E.G.; Sukhorukhov, O.P. (Leningrad NPP (SU))

    1992-01-01

    This paper reports that the results of High Gradient Magnetic Filter (HGMF) model tests for coolant cleaning on Channel High Power Reactor multiple forced circulation line are presented. This coolant (water) was cleaned from iron and radionuclides corrosion products. Extracted particles size was 0.1-5 microns. The numerous experiments showed that the average efficiency for nuclides {sup 95}Nb, {sup 95}Zr and {sup 60}Co was equal to 95-99% in cases when their initial radioactivity was more than 10{sup {minus}7}Cu/1. most of them being extracted at the filter inlet. The obtained results show that this type of HGMF is better than iron balls magnetic filter as the product quality and specific capacity are higher.

  16. Neutron capture on (94)Zr: Resonance parameters and Maxwellian-averaged cross sections

    Tagliente, G; Fujii, K; Abbondanno, U; Aerts, G; Alvarez, H; Alvarez-Velarde, F; Andriamonje, S; Andrzejewski, J; Audouin, L; Badurek, G; Baumann, P; Becvar, F; Belloni, F; Berthoumieux, E; Bisterzo, S; 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; Ferrari, A; Ferreira-Marques, R; Furman, W; Gallino, R; Goncalves, I; Gonzalez-Romero, E; Gramegna, F; Guerrero, C; Gunsing, F; Haas, B; Haight, R; Heil, M; Herrera-Martinez, A; Jericha, E; Kappeler, F; Kadi, Y; Karadimos, D; Karamanis, D; Kerveno, M; Kossionides, E; Krticka, M; Lamboudis, C; Leeb, H; Lindote, A; Lopes, I; Lozano, M; Lukic, S; Marganiec, J; Marrone, S; Martinez, T; Massimi, C; Mastinu, P; 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; Rosetti, M; Rubbia, C; Rudolf, G; Rullhusen, P; Salgado, J; Santos, C; Sarchiapone, L; Savvidis, I; Stephan, C; 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

    2011-01-01

    The neutron capture cross sections of the Zr isotopes play an important role in nucleosynthesis studies. The s-process reaction flow between the Fe seed and the heavier isotopes passes through the neutron magic nucleus (90)Zr and through (91,92,93,94)Zr, but only part of the flow extends to (96)Zr because of the branching point at (95)Zr. Apart from their effect on the s-process flow, the comparably small isotopic (n, gamma) cross sections make Zr also an interesting structural material for nuclear reactors. The (94)Zr (n, gamma) cross section has been measured with high resolution at the spallation neutron source n_TOF at CERN and resonance parameters are reported up to 60 keV neutron energy.

  17. Studies on structural and electrical properties of pure and doped h-YMnO3

    Rathod, K. N.; Rajyaguru, Bhargav; Solanki, Sapana; Shrimali, V. G.; Sagapariya, Khushal; Markna, J. H.; Solanki, P. S.; Shah, N. A.

    2016-05-01

    In the present communication, we report the results of the structural and electrical studies on pure YMnO3 (YMO) and Zr doped Y0.95Zr0.05MnO3 (YZMO) samples, synthesized using low cost sol-gel technique. To understand the structural properties, structural phases present and effect of doping on the structural behavior, X-ray diffraction (XRD) measurements were carried out for both the samples understudy. XRD results reveal the single phasic nature of both the samples having hexagonal unit cell structure. Improved crystal structure has been observed for pure YMnO3 sample while doping of Zr at Y-site degrades the structure of the sample. Improved dielectric constant and enhanced AC conductivity (σa) have been discussed on the basis of charge carrier polarization and correlated barrier hopping due to the localized state.

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

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

    1995-11-01

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

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

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

    1980-02-01

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

  20. Characterization of radioactive aerosols in Tehran research reactor containment

    Moradi Gholamreza

    2015-01-01

    Full Text Available The objectives of this research were to determine the levels of radioactivity in the Tehran research reactor containment and to investigate the mass-size distribution, composition, and concentration of radionuclides during operation of the reactor. A cascade impactor sampler was used to determine the size-activity distributions of radioactive aerosols in each of the sampling stations. Levels of a and b activities were determined based on a counting method using a liquid scintillation counter and smear tests. The total average mass fractions of fine particles (particle diameter dp < 1 mm in all of the sampling stations were approximately 26.75 %, with the mean and standard deviation of 52.15 ± 19.75 mg/m3. The total average mass fractions of coarse particles were approximately 73.2%, with the mean and standard deviation of 71.34 ± 24.57 mg/m3. In addition to natural radionuclides, artificial radionuclides, such as 24Na, 91Sr, 131I, 133I, 103Ru, 82Br, and 140La, may be released into the reactor containment structure. Maximum activity was associated with accumulation-mode particles with diameters less than 400 nm. The results obtained from liquid scintillation counting suggested that the mean specific activity of alpha particles in fine and coarse-modes were 89.7 % and 10.26 %, respectively. The mean specific activity of beta particles in fine and coarse-modes were 81.15 % and 18.51 %, respectively. A large fraction of the radionuclides' mass concentration in the Tehran research reactor containment was associated with coarse-mode particles, in addition, a large fraction of the activity in the aerosol particles was associated with accumulation-mode particles.

  1. Fetoplacental transport of various trace elements in pregnant rat using the multitracer technique

    Enomoto, Shuichi; Hirunuma, Rieko [Radioisotope Technology Division, Cyclotron Center, Institute of Physical and Chemical Research (RIKEN), Wako, Saitama (Japan)

    2001-05-01

    The placenta functions as the barrier between fetus and mother, providing means of regulation of heat exchange, respiration, nutrition, and excretion for the fetus. In this paper, the multitracer technique was applied to study the maternal transport of trace elements via the placenta to the fetus. In this experiment, the multitracer solution used contained the following nuclides: {sup 7}Be, {sup 22}Na, {sup 46}Sc, {sup 48}V, {sup 52}Mn, {sup 59}Fe, {sup 56}Co, {sup 65}Zn, {sup 67}Ga, {sup 74}As, {sup 75}Se, {sup 84}Rb, {sup 85}Sr, {sup 87}Y, {sup 88}Zr, {sup 96}Tc, {sup 101m}Rh, and {sup 103}Ru. We examined the time dependence of the uptake amounts about various elements. From these results, we observed a large difference in the time dependencies between elements and the elements were classified into three groups. Group I elements, such as Be, Sc, V, As, Y, Zr, Tc, Rh, and Ru, are transported to the placenta from the maternal blood and only accumulates in the placenta. Group II elements, such as Na, Co, Ga, Rb, and Sr, are transported to the placenta from the maternal blood and accumulate in the placenta, fetus, and amniotic fluid. Group III elements, such as Mn, Fe, Zn, and Se, are transported to the placenta from the maternal blood and mainly accumulate in the fetus. From these results, it was considered that the placenta is a highly selective filters because essential elements such as Group III elements are readily transported from the placental membrane to the growing fetus, whereas nonessential metals such as Group I elements have difficulty penetrating the placental barrier that protects the fetus from the toxic effects of these elements. (author)

  2. Spectroscopical study of the yrast and yrare structure in far-from-stability nuclei; Etude spectroscopique de la structure yrast et yrare de noyaux loin de la stabilite

    Hoellinger Fabien [Institut de Recherches Subatomiques, 23, Rue du Loess, BP 28, 67037 Strasbourg Cedex 2 (France)]|[Universite Louis Pasteur, 67 - Strasbourg (France)

    1999-01-13

    The nuclear structure study of neutron-rich nuclei was realized with the EUROGAM II array in two different experiments. The first study consisted in the analysis of the product of spontaneous fission of {sup 248}Cm. Three neutron-rich cerium isotopes {sup 147,149,151}Ce were analyzed. A level scheme for {sup 151}Ce is presented for the first time. The yrast structure of the three nuclei does not show alternative parity bands as expected in this region of octupole deformations. We studied the rotational structure of the bands and this leads to suggest Nilsson configurations to some of them. The aim of this second experiment was the study of the nuclei {sup 99}Mo, {sup 101}Tc, {sup 103}Ru. The three nuclei are situated on the neutron-rich side of the nuclear chart and are produced as fission fragments of a heavy-ion induced reaction. Some bands are extended to higher spins and some new bands are observed. The structure of the rotational bands is interpreted by means of the Hartree-Fock-Bogolyubov model. A last experiment intended to study the structure of the proton-rich nucleus {sup 223}Pa has been achieved with the JURO+RITU array located at Jyvaeskylae (Finland). In this proton-rich actinide region, the nuclei develop octupole features around Z{approx_equal}88, N{approx_equal}132. The analysis of this experiment leads to the first assignment of gamma transitions to the {sup 223}Pa. (author) 91 refs., 78 figs., 16 tabs.

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

    Favalli, A., E-mail: afavalli@lanl.gov [Los Alamos National Laboratory, Los Alamos, NM (United States); Vo, D. [Los Alamos National Laboratory, Los Alamos, NM (United States); Grogan, B. [Oak Ridge National Laboratory, Oak Ridge, TN (United States); Jansson, P. [Uppsala University, Uppsala (Sweden); Liljenfeldt, H. [Oak Ridge National Laboratory, Oak Ridge, TN (United States); Mozin, V. [Lawrence Livermore National Laboratory, Livermore, CA (United States); Schwalbach, P. [European Commission, DG Energy, Euratom Safeguards Luxemburg, Luxemburg (Luxembourg); Sjöland, A. [Swedish Nuclear Fuel and Waste Management Company, Stockholm (Sweden); Tobin, S.J.; Trellue, H. [Los Alamos National Laboratory, Los Alamos, NM (United States); Vaccaro, S. [European Commission, DG Energy, Euratom Safeguards Luxemburg, Luxemburg (Luxembourg)

    2016-06-01

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

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

    Mun, Ch

    2007-03-15

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

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

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

    2016-06-01

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

  6. Summary technical report on the electrochemical treatment of alkaline nuclear wastes

    Hobbs, D.T.

    1994-07-30

    This report summarizes the laboratory studies investigating the electrolytic treatment of alkaline solutions carried out under the direction of the Savannah River Technology Center from 1985-1992. Electrolytic treatment has been demonstrated at the laboratory scale to be feasible for the destruction of nitrate and nitrite and the removal of radioactive species such as {sup 99}Tc and {sup 106}Ru from Savannah River Site (SRS) decontaminated salt solution and other alkaline wastes. The reaction rate and current efficiency for the removal of these species are dependent on cell configuration, electrode material, nature of electrode surface, waste composition, current density, and temperature. Nitrogen, ammonia, and nitrous oxide have been identified as the nitrogen-containing reaction products from the electrochemical reduction of nitrate and nitrite under alkaline conditions. The reaction mechanism for the reduction is very complex. Voltammetric studies indicated that the electrode reactions involve surface phenomena and are not necessarily mass transfer controlled. In an undivided cell, results suggest an electrocatalytic role for oxygen via the generation of the superoxide anion. In general, more efficient reduction of nitrite and nitrate occurs at cathode materials with higher overpotentials for hydrogen evolution. Nitrate and nitrite destruction has also been demonstrated in engineering-scale flow reactors. In flow reactors, the nitrate/nitrite destruction efficiency is improved with an increase in the current density, temperature, and when the cell is operated in a divided cell configuration. Nafion{reg_sign} cation exchange membranes have exhibited good stability and consistent performance as separators in the divided-cell tests. The membranes were also shown to be unaffected by radiation at doses approximating four years of cell operation in treating decontaminated salt solution.

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

    Arnold, W.D.; Bostick, D.T.; Burgess, M.W.; Taylor, P.A.; Perona, J.J.; Kent, T.E.

    1994-10-01

    Improved centralized treatment methods are needed in the management of liquid low-level waste (LLLW) at Oak Ridge National Laboratory (ORNL). LLLW, which usually contains radioactive contaminants at concentrations up to millicurie-per-liter levels, has accumulated in underground storage tanks for over 10 years and has reached a volume of over 350,000 gal. These wastes have been collected since 1984 and are a complex mixture of wastes from past nuclear energy research activities. The waste is a highly alkaline 4-5 M NaNO{sub 3} solution with smaller amounts of other salts. This type of waste will continue to be generated as a consequence of future ORNL research programs. Future LLLW (referred to as newly generated LLLW or NGLLLW) is expected to a highly alkaline solution of sodium carbonate and sodium hydroxide with a smaller concentration of sodium nitrate. New treatment facilities are needed to improve the manner in which these wastes are managed. These facilities must be capable of separating and reducing the volume of radioactive contaminants to small stable waste forms. Treated liquids must meet criteria for either discharge to the environment or solidification for onsite disposal. Laboratory testing was performed using simulated waste solutions prepared using the available characterization information as a basis. Testing was conducted to evaluate various methods for selective removal of the major contaminants. The major contaminants requiring removal from Melton Valley Storage Tank liquids are {sup 90}Sr and {sup 137}Cs. Principal contaminants in NGLLLW are {sup 9O}Sr, {sup 137}Cs, and {sup 106}Ru. Strontium removal testing began with literature studies and scoping tests with several ion-exchange materials and sorbents.

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

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

    1998-07-01

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

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

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

    2016-09-01

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

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

    Vo, D., E-mail: ducvo@lanl.gov [Los Alamos National Laboratory, Los Alamos, NM (United States); Favalli, A. [Los Alamos National Laboratory, Los Alamos, NM (United States); Grogan, B. [Oak Ridge National Laboratory, Oak Ridge, TN (United States); Jansson, P. [Uppsala University, Uppsala (Sweden); Liljenfeldt, H. [Oak Ridge National Laboratory, Oak Ridge, TN (United States); Mozin, V. [Lawrence Livermore National Laboratory, Livermore, CA (United States); Schwalbach, P. [European Atomic Energy Community (EURATOM), Luxemburg (Luxembourg); Sjöland, A. [Swedish Nuclear Fuel and Waste Management Company, Stockholm (Sweden); Tobin, S.; Trellue, H. [Los Alamos National Laboratory, Los Alamos, NM (United States); Vaccaro, S. [European Atomic Energy Community (EURATOM), Luxemburg (Luxembourg)

    2016-09-11

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

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

    Thibert, V.

    1995-07-01

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

  12. Deposition of fission and activation products after the Fukushima Dai-ichi nuclear power plant accident.

    Shozugawa, Katsumi; Nogawa, Norio; Matsuo, Motoyuki

    2012-04-01

    The Great Eastern Japan Earthquake on March 11, 2011, damaged reactor cooling systems at Fukushima Dai-ichi nuclear power plant. The subsequent venting operation and hydrogen explosion resulted in a large radioactive nuclide emission from reactor containers into the environment. Here, we collected environmental samples such as soil, plant species, and water on April 10, 2011, in front of the power plant main gate as well as 35 km away in Iitate village, and observed gamma-rays with a Ge(Li) semiconductor detector. We observed activation products ((239)Np and (59)Fe) and fission products ((131)I, (134)Cs ((133)Cs), (137)Cs, (110m)Ag ((109)Ag), (132)Te, (132)I, (140)Ba, (140)La, (91)Sr, (91)Y, (95)Zr, and (95)Nb). (239)Np is the parent nuclide of (239)Pu; (59)Fe are presumably activation products of (58)Fe obtained by corrosion of cooling pipes. The results show that these activation and fission products, diffused within a month of the accident.

  13. Excitation functions of {sup nat}Zr + p nuclear processes up to 70 MeV: New measurements and compilation

    Szelecsényi, F., E-mail: szele@atomki.hu [Cyclotron Application Department, Institute for Nuclear Research, Hungarian Academy of Sciences, Bem tér 18/c, Debrecen H-4026 (Hungary); Steyn, G.F. [iThemba Laboratory for Accelerator Based Sciences, Faure, P.O. Box 722, Somerset West 7129 (South Africa); Kovács, Z. [Cyclotron Application Department, Institute for Nuclear Research, Hungarian Academy of Sciences, Bem tér 18/c, Debrecen H-4026 (Hungary); Vermeulen, C. [Centre for Radiopharmaceutical Sciences, Paul Scherrer Institute, 5232 Villigen-PSI (Switzerland); Nagatsu, K.; Zhang, M.-R.; Suzuki, K. [Molecular Imaging Center, National Institute of Radiological Sciences, 4-9-1 Anagawa, Inage-ku-Chiba, 263-8555 (Japan)

    2015-01-15

    Excitation functions for the formation of various radionuclides of Nb, Zr, Y and Sr in proton-induced reactions on natural zirconium were measured up to 66 MeV using the stacked-foil technique. New data are presented for {sup 89m,89g}Nb, {sup 90(m+g)}Nb, {sup 91m}Nb, {sup 92m}Nb, {sup 95m,95g}Nb, {sup 96}Nb, {sup 86}Zr, {sup 87(m+g)}Zr, {sup 88}Zr, {sup 89(0.94m+g)}Zr, {sup 95}Zr, {sup 85m,85g}Y, {sup 86m,86(0.99m+g)}Y, {sup 87m,87(0.984m+g)}Y, {sup 88}Y, {sup 90m}Y, {sup 91m}Y and {sup 85(0.87m+g)}Sr. The experimental results are compared with the available literature data as well as the evaluated theoretical predictions by means of the TALYS code, up to 70 MeV, as compiled in the TENDL-2013 library. For a number of short-lived radionuclides, i.e., {sup 85m}Y, {sup 85g}Y, {sup 86m}Y, {sup 90m}Y, {sup 91m}Y and {sup 87(m+g)}Zr, the present experimental cross sections are likely the first to be reported for their formation in {sup nat}Zr + p.

  14. Preparation of ZrO2(3Y)encapsulated Al2O3 nanometer composite powders%ZrO2(3Y)包裹Al2O3纳米复合粉体的制备

    杨建; 刘姣; 丘泰; 林洁

    2006-01-01

    以pH值缓冲溶液为沉淀剂,用非均匀成核和液相共沉淀相结合的方法合成出了ZrO2(3Y)包裹Al2O3纳米复合粉体.用XRD、TEM对所制备粉体进行了表征.研究表明:加入分散剂使Al2O3悬浮液的等电点向酸性区移动,Zeta电位绝对值增大,其中pH值为9.56对应的Zeta电位绝对值最大,悬浮液最稳定.Al2O3悬浮液pH值为9.5,ZrOCl2和YCl3混合溶液浓度为0.2 mol·L-1时前驱体的收得率最高.600℃煅烧后得到的粉体中只有α-Al2O3、t-ZrO2两种物相,在Al2O3颗粒表面附着10 nm左右的ZrO2(3Y)颗粒.

  15. The impact of updated Zr neutron-capture cross sections and new asymptotic giant branch models on our understanding of the s process and the origin of stardust

    Lugaro, Maria; Karakas, Amanda I; Milazzo, Paolo M; Kaeppeler, Franz; Davis, Andrew M; Savina, Michael R

    2013-01-01

    We present model predictions for the Zr isotopic ratios produced by slow neutron captures in C-rich asymptotic giant branch (AGB) stars of masses 1.25 to 4 Msun and metallicities Z=0.01 to 0.03, and compare them to data from single meteoritic stardust silicon carbide (SiC) and high-density graphite grains that condensed in the outflows of these stars. We compare predictions produced using the Zr neutron-capture cross section from Bao et al. (2000) and from n_TOF experiments at CERN, and present a new evaluation for the neutron-capture cross section of the unstable isotope 95Zr, the branching point leading to the production of 96Zr. The new cross sections generally presents an improved match with the observational data, except for the 92Zr/94Zr ratios, which are on average still substantially higher than predicted. The 96Zr/94Zr ratios can be explained using our range of initial stellar masses, with the most 96Zr-depleted grains originating from AGB stars of masses 1.8 - 3 Msun, and the others from either lowe...

  16. Evaluation of fission product yields from fission spectrum n+239Pu using a meta analysis of benchmark data

    Chadwick, Mark B.

    2009-10-01

    Los Alamos conducted a dual fission-chamber experiment in the 1970s in the Bigten critical assembly to determine fission product data in a fast (fission neutron spectrum) environment, and this defined the Laboratory's fission basis today. We describe how the data from this experiment are consistent with other benchmark fission product yield measurements for 95,97Zr, 140Ba, 143,144Ce, 137Cs from the NIST-led ILRR fission chamber experiments, and from Maeck's mass-spectrometry data. We perform a new evaluation of the fission product yields that is planned for ENDF/B-VII.1. Because the measurement database for some of the FPs is small—especially for 147Nd and 99Mo—we use a meta-analysis that incorporates insights from other accurately-measured benchmark FP data. The %-relative changes compared to ENDF/B-VI are small for some FPs (less than 1% for 95Zr, 140Ba, 144Ce), but are larger for 99Mo (3%) and 147Nd (5%). We suggest an incident neutron energy dependence to the 147Nd fission product yield that accounts for observed differences in the FPY at a few-hundred keV average energy in fast reactors versus measurements made at higher average energies.

  17. The use of algae in monitoring discharges of radionuclides. Experiences from the 1992 and 1993 monitoring programmes at the Swedish nuclear power plants

    Snoeijs, P. [Uppsala Univ. (Sweden). Dept. of Ecological Botany; Simenstad, P. [Swedish Radiation Protection Inst., Stockholm (Sweden)

    1995-01-01

    All four Swedish nuclear power plants (Forsmark, Oskarshamn, Barsebaeck and Ringhals) use brackish water as coolant (Baltic Sea and Swedish west coast). Radionuclides are discharged together with the cooling water. The gamma spectra of monthly algal samples harvested in 1992 and 1993 close to the discharge points of these power plants were determined within the routine monitoring programmes. The main radionuclides detected in the algal samples were {sup 54}Mn, {sup 58}Co, {sup 60}Co and {sup 137}Cs. Most {sup 137}Cs in the samples from the northern Baltic Sea (Forsmark) still originated from the 1986 Chernobyl accident. Other radionuclides, notably {sup 51}Cr, {sup 65}Zn, {sup 95}Zr, {sup 95}Nb, {sup 110m}Ag, {sup 124}b, {sup 125}Sb and {sup 134}Cs, were regularly detected at s of the sites. Transfer factors from discharge to algae were generally in the order of 0.3-3 Bq kg{sup -1} per MBq discharge. For the major discharged radionuclides, significant linear relationships were in most cases found between discharges and concentrations in algal samples. Differences in transfer factors and regression coefficients were explained by location of the sampling sites and type of radionuclide. It is concluded that algal samples provide useful complements to water and sediment samples in the monitoring programmes since radionuclide concentrations are much higher in algal samples and proportional to the discharges. 21 refs, figs.

  18. Thermochemical Energy Storage through De/Hydrogenation of Organic Liquids: Reactions of Organic Liquids on Metal Hydrides.

    Ulmer, Ulrich; Cholewa, Martin; Diemant, Thomas; Bonatto Minella, Christian; Dittmeyer, Roland; Behm, R Jürgen; Fichtner, Maximilian

    2016-06-08

    A study of the reactions of liquid acetone and toluene on transition metal hydrides, which can be used in thermal energy or hydrogen storage applications, is presented. Hydrogen is confined in TiFe, Ti0.95Zr0.05Mn1.49V0.45Fe0.06 ("Hydralloy C5"), and V40Fe8Ti26Cr26 after contact with acetone. Toluene passivates V40Fe8Ti26Cr26 completely for hydrogen desorption while TiFe is only mildly deactivated and desorption is not blocked at all in the case of Hydralloy C5. LaNi5 is inert toward both organic liquids. Gas chromatography (GC) investigations reveal that CO, propane, and propene are formed during hydrogen desorption from V40Fe8Ti26Cr26 in liquid acetone, and methylcyclohexane is formed in the case of liquid toluene. These reactions do not occur if dehydrogenated samples are used, which indicates an enhanced surface reactivity during hydrogen desorption. Significant amounts of carbon-containing species are detected at the surface and subsurface of acetone- and toluene-treated V40Fe8Ti26Cr26 by X-ray photoelectron spectroscopy (XPS). The modification of the surface and subsurface chemistry and the resulting blocking of catalytic sites is believed to be responsible for the containment of hydrogen in the bulk. The surface passivation reactions occur only during hydrogen desorption of the samples.

  19. Radioactivity levels in major French rivers: summary of monitoring chronicles acquired over the past thirty years and current status.

    Eyrolle, Frédérique; Claval, David; Gontier, Gilles; Antonelli, Christelle

    2008-07-01

    Since the beginning of the 1990 s, liquid releases of gamma-emitting radionuclides from French nuclear facilities have generally fallen by almost 85%. Almost 65% of gamma-emitting liquid effluents released into freshwater rivers concerned the River Rhône (Southeast France), with around 85% of this originating from the Marcoule spent fuel reprocessing plant. Upstream of French nuclear plants, artificial radionuclides still detected by gamma spectrometry in 2006, include (137)Cs, (131)I as well as (60)Co, (58)Co and (54)Mn in the case of the Rhine (Switzerland nuclear industries). In the wake of the fallout from the Chernobyl accident, (103)Ru, (106)Rh-Ru, (110 m)Ag, (141)Ce and (129)Te were detected in rivers in the east of France. Some of these radionuclides were found in aquatic plants until 1989. In eastern France, (137)Cs activity in river sediments and mosses is still today two to three times greater than that observed in similar environments in western France. No (134)Cs has been detected upstream of nuclear plants in French rivers since 2001. Downstream of nuclear plants, the gamma emitters still detected regularly in rivers in 2006 are (137)Cs, (134)Cs, (60)Co, (58)Co, (110 m)Ag, (54)Mn, (131)I, together with (241)Am downstream of the Marcoule spent fuel reprocessing plant. Alpha and beta emitters such as plutonium isotopes and (90)Sr first entered freshwaters at the early 1950s due to the leaching of soils contaminated by atmospheric fallout from nuclear testing. These elements were also introduced, in the case of the Rhône River, via effluent from the Marcoule reprocessing plant. Until the mid 1990 s, plutonium isotope levels observed in the lower reaches of the Rhône were 10 to 1000 times higher than those observed in other French freshwaters. Data gathered over a period of almost thirty years of radioecological studies reveal that the only radionuclides detected in fish muscles are (137)Cs, (90)Sr, plutonium isotopes and (241)Am. At the scale of the

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

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

    2002-01-31

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

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

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

    2000-06-28

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

  2. IMITATION OF STANDARD VOLUMETRIC ACTIVITY METAL SAMPLES

    A. I. Zhukouski

    2016-01-01

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

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

    Charmasson, S

    1998-07-01

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

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

    Charmasson, S

    1998-07-01

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

  5. Vertical distribution and estimated doses from artificial radionuclides in soil samples around the Chernobyl nuclear power plant and the Semipalatinsk nuclear testing site.

    Yasuyuki Taira

    Full Text Available For the current on-site evaluation of the environmental contamination and contributory external exposure after the accident at the Chernobyl Nuclear Power Plant (CNPP and the nuclear tests at the Semipalatinsk Nuclear Testing Site (SNTS, the concentrations of artificial radionuclides in soil samples from each area were analyzed by gamma spectrometry. Four artificial radionuclides ((241Am, (134Cs, (137Cs, and (60Co were detected in surface soil around CNPP, whereas seven artificial radionuclides ((241Am, (57Co, (137Cs, (95Zr, (95Nb, (58Co, and (60Co were detected in surface soil around SNTS. Effective doses around CNPP were over the public dose limit of 1 mSv/y (International Commission on Radiological Protection, 1991. These levels in a contaminated area 12 km from Unit 4 were high, whereas levels in a decontaminated area 12 km from Unit 4 and another contaminated area 15 km from Unit 4 were comparatively low. On the other hand, the effective doses around SNTS were below the public dose limit. These findings suggest that the environmental contamination and effective doses on the ground definitely decrease with decontamination such as removing surface soil, although the effective doses of the sampling points around CNPP in the present study were all over the public dose limit. Thus, the remediation of soil as a countermeasure could be an extremely effective method not only for areas around CNPP and SNTS but also for areas around the Fukushima Dai-ichi Nuclear Power Plant (FNPP, and external exposure levels will be certainly reduced. Long-term follow-up of environmental monitoring around CNPP, SNTS, and FNPP, as well as evaluation of the health effects in the population residing around these areas, could contribute to radiation safety and reduce unnecessary exposure to the public.

  6. The impact of updated Zr neutron-capture cross sections and new asymptotic giant branch models on our understanding of the S process and the origin of stardust

    Lugaro, Maria [Monash Centre for Astrophysics (MoCA), Monash University, Clayton, VIC 3800 (Australia); Tagliente, Giuseppe [Istituto Nazionale di Fisica Nucleare (INFN), Bari (Italy); Karakas, Amanda I. [Research School of Astronomy and Astrophysics, Australian National University, Canberra, ACT 2611 (Australia); Milazzo, Paolo M. [Istituto Nazionale di Fisica Nucleare (INFN), Trieste (Italy); Käppeler, Franz [Karlsruhe Institute of Technology, Campus North, D-76021 Karlsruhe (Germany); Davis, Andrew M. [The Department of the Geophysical Sciences, The University of Chicago, Chicago, IL 60637 (United States); Savina, Michael R., E-mail: maria.lugaro@monash.edu, E-mail: giuseppe.tagliente@ba.infn.it, E-mail: amanda.karakas@anu.edu.au, E-mail: paolo.milazzo@ts.infn.it, E-mail: franz.kaeppeler@kit.edu, E-mail: a-davis@uchicago.edu, E-mail: msavina@anl.gov [Materials Science Division, Argonne National Laboratory, Argonne, IL 60439 (United States)

    2014-01-01

    We present model predictions for the Zr isotopic ratios produced by slow neutron captures in C-rich asymptotic giant branch (AGB) stars of masses 1.25-4 M {sub ☉} and metallicities Z = 0.01-0.03, and compare them to data from single meteoritic stardust silicon carbide (SiC) and high-density graphite grains that condensed in the outflows of these stars. We compare predictions produced using the Zr neutron-capture cross sections from Bao et al. and from n{sub T}OF experiments at CERN, and present a new evaluation for the neutron-capture cross section of the unstable isotope {sup 95}Zr, the branching point leading to the production of {sup 96}Zr. The new cross sections generally present an improved match with the observational data, except for the {sup 92}Zr/{sup 94}Zr ratios, which are on average still substantially higher than predicted. The {sup 96}Zr/{sup 94}Zr ratios can be explained using our range of initial stellar masses, with the most {sup 96}Zr-depleted grains originating from AGB stars of masses 1.8-3 M {sub ☉} and the others from either lower or higher masses. The {sup 90,} {sup 91}Zr/{sup 94}Zr variations measured in the grains are well reproduced by the range of stellar metallicities considered here, which is the same needed to cover the Si composition of the grains produced by the chemical evolution of the Galaxy. The {sup 92}Zr/{sup 94}Zr versus {sup 29}Si/{sup 28}Si positive correlation observed in the available data suggests that stellar metallicity rather than rotation plays the major role in covering the {sup 90,} {sup 91,} {sup 92}Zr/{sup 94}Zr spread.

  7. Detection of coal combustion products in stream sediments by chemical analysis and magnetic-susceptibility measurements

    Franciskovic-Bilinski, S. [Rudjer Boskovic Institute, Zagreb (Croatia)

    2008-02-15

    Coal slag and ash, obtained from burning coal in a textile factory in Duga Resa (Croatia) was discharged directly into the Mreznica River for 110 y (1884-1994), from where it travelled to the Korana River and further to the Kupa River at Karlovac, a total of about 50 km from its source. Of 54 elements determined by inductively coupled plasma mass spectrometry (ICP-MS) in the {lt}2 mm sediment fraction, a number of anomalously high levels were recorded. The geoaccumulation index (I{sub geo}) for the anomalous elements were: Hg (1.88), B (4.05), Na (1.44). Al (2.05), V (1.65), Cr (1.20), Fe (1.18), Ni (2.10), Cu (2.37), Sr (0.97), Zr (3.27), Mo (3.34) and U (4.03). Low-field magnetic susceptibility (MS) was measured for each sample. The I{sub geo} for MS in the anomalous region is 5.85. Correlation analysis showed good correlation ({gt}0.90) of MS with: B (0.96), U (0.95), Zr (0.94), Sr (0.93), Na (0.92), Mo (0.92) and Ni (0.90). Cluster analysis of R-modality indicates that MS is linked to B, Mo, Na and U. Low correlation of MS with Fe (0.36) suggests that Fe in stream sediments is not in a ferromagnetic form. Neither maghemite, nor magnetite phases were identified by X-ray diffraction (XRD) in the sediments. Low-field magnetic susceptibility provides an indicator of contamination of river sediments by transported coal slag and ash, although it cannot be prescribed to a single element.

  8. A comparison of methods for the estimation of the proportion of microbial nitrogen in duodenal digesta, and of correction for microbial contamination in nylon bags incubated in the rumen of sheep.

    Kennedy, P M; Hazlewood, G P; Milligan, L P

    1984-09-01

    Four sheep, each fitted with cannulas in the rumen and proximal duodenum, were given two diets (1390 g dry matter (DM)/d) consisting of lucerne (Medicago sativa) pellets (24.2 g nitrogen/kg DM) plus pelleted reed canary grass (Phalaris arundinacea; 14.1 g N/kg DM) or chopped hay (11.8 g N/kg DM) at intervals of 2 h. Flow of duodenal digesta measured by reference to the markers 51Cr-EDTA and 103Ru-phenanthroline indicated a net gain of 5.8-7.5 g non-ammonia-N (NAN) between mouth and duodenum. The proportion of microbial N in duodenal digesta N was estimated using 15N and 35S incorporation into bacteria and digesta. Two methods of analysis for 35S content, the Bird & Fountain (1970; B&F method) and the Mathers & Miller (1980; M&M method), were used. (15NH4)2SO4 and Na2(35)SO4 were infused into the rumen for 3.5 d before and 4.0 d during sampling. A bacterial fraction was prepared from the fluid phases of sampled duodenal digesta and rumen contents by differential centrifugation. In addition, samples of ground canary grass and of lucerne were incubated in nylon bags in the rumen for 3-48 h during the infusion. Each of the 35S analytical methods yielded similar values of 35S content of isolated rumen or duodenal bacteria, but there was more (P less than 0.05) incorporation of 15N into rumen than into duodenal bacteria. Relative to values obtained using the M&M method and 15N incorporation, the B&F method for S analysis yielded higher (P less than 0.05) estimates of microbial content of duodenal digesta from sheep given chopped reed canary grass. 35S activity associated with washed nylon-bag residues increased rapidly with time-period of incubation and was substantially greater (P less than 0.05) when analysed by the B&F method compared with the M&M method. The 35S content (/g DM) of adherent bacteria removed from nylon-bag residues by homogenization in a second experiment varied from 0.65 to 1.88 that of free-living bacteria isolated from rumen fluid by differential

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

    Korobova, E.

    2012-04-01

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

  10. 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

    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

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

    Eibling, R.

    2011-09-28

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

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

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

    2014-07-01

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

  13. Impact of {sup 134}Cs and {sup 137}Cs from the Chernobyl reactor accident on the Spanish Mediterranean marine environment

    Molero, J.; Sanchez-Cabeza, J.A.; Merino, J. [Grup de Fisica de les Radiacions, Departament de Fisica, Facultat de Ciencies, Universitat Autonoma de Barcelona, 08193 Bellaterra (Spain); Mitchell, P.I. [Laboratory of Radiation Physics, University College, Dublin (Ireland); Vidal-Quadras, A. [Grup de Fisica de les Radiacions, Departament de Fisica, Facultat de Ciencies, Universitat Autonoma de Barcelona, 08193 Bellaterra (Spain)

    1999-05-01

    As part of a study aiming to establish the distribution and bioavailability of man-made radionuclides in the marine environment, radiocaesium levels were determined in large volume sea water samples and in the sea-grass Posidonia oceanica collected along the Spanish Mediterranean coast. Results obtained from 1987 to 1991 showed the enhancement of radiocaesium levels in the Spanish Mediterranean marine environment after the Chernobyl accident. The well-known {sup 134}Cs/{sup 137}Cs isotopic ratio in Chernobyl fresh deposition was used to identify the weapon tests fall-out and Chernobyl deposition components. {sup 137}Cs and {sup 134}Cs mean concentrations in surface waters from the Spanish Mediterranean shoreline were 4.8{+-}0.2 and 0.27{+-}0.01 Bq m{sup -3}, respectively. {sup 137}Cs concentration incorporated into Mediterranean waters as a consequence of the post-Chernobyl deposition was estimated to be 1.16{+-}0.04 Bq m{sup -3}, which is a 33{+-}2% increase over the previous levels. {sup 137}Cs estimated inventory in the surface water layer (0-50 m) of the Catalan-Balearic basin was 17.4{+-}0.5 TBq for {sup 137}Cs, of which 4.3{+-}0.2 TBq must be attributed to post-Chernobyl deposition, and 1.00{+-}0.04 TBq for {sup 134}Cs. Activation and fission products such as {sup 106}Ru, {sup 110m}Ag, {sup 134}Cs, {sup 137}Cs and {sup 144}Ce, were detected in all samples of Posidonia oceanica. Mean radiocaesium levels in the bioindicator were 1.02{+-}0.25 and 0.20{+-}0.03 Bq kg{sup -1} for {sup 137}Cs and {sup 134}Cs, respectively, corresponding to a mean isotopic ratio {sup 134}Cs/{sup 137}Cs equal to 0.20{+-}0.04 (1987). {sup 137}Cs activity incorporated by Posidonia oceanica after the Chernobyl deposition over the Mediterranean Sea was estimated as 0.51{+-}0.08 Bq kg{sup -1}. Therefore, {sup 137}Cs specific activity had increased 100{+-}40% one year after the accident. Low level radioactive liquid effluents from the nuclear power plants located on the southern Catalan

  14. Formation of Microbial Mats and Salt in Radioactive Paddy Soils in Fukushima, Japan

    Kazue Tazaki

    2015-12-01

    Full Text Available Coastal areas in Minami-soma City, Fukushima, Japan, were seriously damaged by radioactive contamination from the Fukushima Daiichi Nuclear Power Plant (FDNPP accident that caused multiple pollution by tsunami and radionuclide exposure, after the Great East Japan Earthquake, on 11 March 2011. Some areas will remain no-go zones because radiation levels remain high. In Minami-soma, only 26 percent of decontamination work had been finished by the end of July in 2015. Here, we report the characterization of microbial mats and salt found on flooded paddy fields at Karasuzaki, Minami-soma City, Fukushima Prefecture, Japan which have been heavily contaminated by radionuclides, especially by Cs (134Cs, 137Cs, 40K, Sr (89Sr, 90Sr, and 91 or 95Zr even though it is more than 30 km north of the FDNPP. We document the mineralogy, the chemistry, and the micro-morphology, using a combination of micro techniques. The microbial mats were found to consist of diatoms with mineralized halite and gypsum by using X-ray diffraction (XRD. Particular elements concentrated in microbial mats were detected using scanning electron microscopy equipped with energy dispersive spectroscopy (SEM-EDS and X-ray fluorescence (XRF. The objective of this contribution is to illustrate the ability of various diatoms associated with minerals and microorganisms which are capable of absorbing both radionuclides and stable isotopes from polluted paddy soils in extreme conditions. Ge semiconductor analysis of the microbial mats detected 134Cs, 137Cs, and 40K without 131I in 2012 and in 2013. Quantitative analysis associated with the elemental content maps by SEM-EDS indicated the possibility of absorption of radionuclide and stable isotope elements from polluted paddy soils in Fukushima Prefecture. In addition, radionuclides were detected in solar salts made of contaminated sea water collected from the Karasuzaki ocean bath, Minami-soma, Fukushima in 2015, showing high Zr content associated

  15. Establishment of methodology for determination of {sup 93}Zr in radioactive wastes by Liquid Scintillation Counting (LSC) and Inductively Coupled Plasma Mass Spectrometry (ICP-MS); Estabelecimento de metodologia para determinacao de {sup 93}Zr em rejeitos radioativos por Espectrometria de Cintilacao Liquida (LSC) e Espectrometria de Massa com Plasma Indutivamente Acoplado (ICP-MS)

    Oliveira, Thiago Cesar de

    2014-06-01

    The zirconium-93 is a long-lived pure β-particle-emitting radionuclide produced from {sup 235}U fission and from neutron activation of the stable isotope {sup 92}Zr and thus occurring as one of the radionuclides found in nuclear reactors. Due to its long half life, {sup 93}Zr is one of the radionuclides of interest for the performance of assessment studies of waste storage or disposal. Measurement of {sup 93}Zr is difficult owing to its trace level concentration and its low activity in nuclear wastes and further because its certified standards are not frequently available. The aim of this work was to develop a selective radiochemical separation methodology for the determination of {sup 93}Zr in nuclear waste and analyze it by Liquid Scintillation Counting (LSC) and Inductively Coupled Plasma Mass Spectrometry (ICP-MS). To set up the radiochemical separation procedure for zirconium, a tracer solution of {sup 95}Zr and its 724 keV γ-ray measurements by γ- spectrometry were used in order to follow the behavior of zirconium during the radiochemical separation. For the LSC technique a {sup 55}Fe solution, which is one of the major interfering measures zirconium, was used to verify the decontamination factor during the separation process. The efficiency detection for {sup 63}Ni was used to determination of {sup 93}Zr activity in the matrices analyzed. The limit of detection of the 0.05 Bq 1{sup −1} was obtained for {sup 63}Ni standard solutions by using a sample:cocktail ratio of 3:17 mL for Optiphase Hisafe 3 cocktail. For the ICP-MS technique a zirconium stable solution was used to verify the zirconium behavior and recovery during radiochemical separation and a solution of Ba, Co, Eu, Fe, Mn, Nb, Sr and Y was used to verify the decontamination factor during the separation process. A standard solution {sup 93}Nb as isotope for determining the {sup 93}Zr by ICP-MS was used for calibration and analysis. The detection limit of 0.039 ppb was obtained for the standard

  16. Human biokinetic data and a new compartmental model of zirconium - A tracer study with enriched stable isotopes

    Greiter, Matthias B., E-mail: matthias.greiter@helmholtz-muenchen.de; Giussani, Augusto, E-mail: AGiussani@BfS.de; Hoellriegl, Vera, E-mail: vera.hoellriegl@helmholtz-muenchen.de; Li Weibo, E-mail: wli@helmholtz-muenchen.de; Oeh, Uwe, E-mail: uwe.oeh@helmholtz-muenchen.de

    2011-09-01

    Biokinetic models describing the uptake, distribution and excretion of trace elements are an essential tool in nutrition, toxicology, or internal dosimetry of radionuclides. Zirconium, especially its radioisotope {sup 95}Zr, is relevant to radiation protection due to its production in uranium fission and neutron activation of nuclear fuel cladding material. We present a comprehensive set of human data from a tracer study with stable isotopes of zirconium. The data are used to refine a biokinetic model of zirconium. Six female and seven male healthy adult volunteers participated in the study. It includes 16 complete double tracer investigations with oral ingestion and intravenous injection, and seven supplemental investigations. Tracer concentrations were measured in blood plasma and urine collected up to 100 d after tracer administration. The four data sets (two chemical tracer forms in plasma and urine) each encompass 105-240 measured concentration values above detection limits. Total fractional absorption of ingested zirconium was found to be 0.001 for zirconium in citrate-buffered drinking solution and 0.007 for zirconium oxalate solution. Biokinetic models were developed based on the linear first-order kinetic compartmental model approach used by the International Commission on Radiological Protection (ICRP). The main differences of the optimized systemic model of zirconium to the current ICRP model are (1) recycling into the transfer compartment made necessary by the observed tracer clearance from plasma, (2) different parameters related to fractional absorption for each form of the ingested tracer, and (3) a physiologically based excretion pathway to urine. The study considerably expands the knowledge on the biokinetics of zirconium, which was until now dominated by data from animal studies. The proposed systemic model improves the existing ICRP model, yet is based on the same principles and fits well into the ICRP radiation protection approach. - Research

  17. Separation of {sup 90}Nb from zirconium target for application in immuno-PET

    Radchenko, V.; Roesch, F. [Mainz Univ. (Germany). Inst. of Nuclear Chemistry; Filosofov, D.V.; Bochko, O.K.; Lebedev, N.A.; Rakhimov, A.V. [Joint Institute for Nuclear Research, Dubna, Moscow Region (Russian Federation). Dzhelepov Laboratory of Nuclear Problems; Hauser, H.; Eisenhut, M. [German Cancer Research Center, Heidelberg (Germany). Radiopharmaceutical Chemistry; Aksenov, N.V.; Bozhikov, G.A. [Joint Institute for Nuclear Research, Dubna, Moscow Region (Russian Federation). Flerov Laboratory of Nuclear Reactions; Ponsard, B. [Belgian Nuclear Research Centre (SCKCEN), Mol (Belgium). Radioisotopes and NTD Silicon Production

    2014-07-01

    Fast progressing immuno-PET asks to explore new radionuclides. One of the promising candidates is {sup 90}Nb. It has a half-life of 14.6 h that allows visualizing and quantifying biological processes with medium and slow kinetics, such as tumor accumulation of antibodies and antibodies fragments or drug delivery systems and nanoparticles. {sup 90}Nb exhibits a positron branching of 53% and an average kinetic energy of emitted positrons of E{sub mean} = 0.35 MeV. Currently, radionuclide production routes and NbV labeling techniques are explored to turn this radionuclide into a useful imaging probe. However, efficient separation of {sup 90}Nb from irradiated targets remains in challenge. Ion exchange based separation of {sup 90}Nb from zirconium targets was investigated in systems AG 1 x 8 - HCl/H{sub 2}O{sub 2} and UTEVA-HCl. {sup 95}Nb (t{sub 1/2} = 35.0 d), {sup 95}Zr (t{sub 1/2} = 64.0 d) and {sup 92m}Nb (t{sub 1/2} = 10.15 d) were chosen for studies on distribution coefficients. Separation after AG 1 x 8 anion exchange yields 99% of {sup 90/95}Nb. Subsequent use of a solid-phase extraction step on UTEVA resin further decontaminates {sup 90/95}Nb from traces of zirconium with yields 95% of {sup 90/95}Nb. A semi-automated separation takes one hour to obtain an overall recovery of {sup 90/95}Nb of 90%. The amount of Zr was reduced by factor of 10{sup 8}. The selected separation provides rapid preparation (< 1 h) of high purity {sup 90}Nb appropriate for the synthesis of {sup 90}Nb-radiopharmaceuticals, relevant for purposes of immuno-PET. Applying the radioniobium obtained, {sup 90/95}Nb-labeling of a monoclonal antibody (rituximab) modified with desferrioxamine achieved labeling yields of > 90% after 1 h incubation at room temperature. (orig.)

  18. Fission Product Yields from Fission Spectrum n+ 239Pu for ENDF/B-VII.1

    Chadwick, M. B.; Kawano, T.; Barr, D. W.; Mac Innes, M. R.; Kahler, A. C.; Graves, T.; Selby, H.; Burns, C. J.; Inkret, W. C.; Keksis, A. L.; Lestone, J. P.; Sierk, A. J.; Talou, P.

    2010-12-01

    We describe a new cumulated fission product yield (FPY) evaluation for fission spectrum neutrons on plutonium that updates the ENDF/B-VI evaluation by England and Rider, for the forthcoming ENDF/B-VII.1 database release. We focus on FPs that are needed for high accuracy burnup assessments; that is, for inferring the number of fissions in a neutron environment. Los Alamos conducted an experiment in the 1970s in the Bigten fast critical assembly to determine fission product yields as part of the Interlaboratory Reaction Rate (ILRR) collaboration, and this has defined the Laboratory's fission standard to this day. Our evaluation includes use of the LANL-ILRR measurements (not previously available to evaluators) as well as other Laboratory FPY measurements published in the literature, especially the high-accuracy mass spectrometry data from Maeck and others. Because the measurement database for some of the FPs is small — especially for 99Mo — we use a meta-analysis that incorporates insights from other accurately-measured benchmark FP data, using R-value ratio measurements. The meta-analysis supports the FP measurements from the LANL-ILRR experiment. Differences between our new evaluations and ENDF/B-VI are small for some FPs (less than 1-2%-relative for 95Zr, 140Ba, 144Ce), but are larger for 99Mo (4%-relative) and 147Nd (5%-relative, at 1.5 MeV) respectively. We present evidence for an incident neutron energy dependence to the 147Nd fission product yield that accounts for observed differences in the FPY at a few-hundred keV average energy in fast reactors versus measurements made at higher average neutron energies in Los Alamos' fast critical assemblies. Accounting for such FPY neutron energy dependencies is important if one wants to reach a goal of determining the number of fissions to accuracies of 1-2%. An evaluation of the energy-dependence of fission product yields is given for all A values based on systematical trends in the measured data, with a focus on

  19. Фазообразование и стабильность твёрдых растворов в наноразмерных прекурсорах на основе диоксида циркония, полученных криохимическими методами

    КУРАПОВА ОЛЬГА ЮРЬЕВНА; КОНАКОВ ВЛАДИМИР ГЕННАДИЕВИЧ; ГОЛУБЕВ СЕРГЕЙ НИКОЛАЕВИЧ; УШАКОВ ВИКТОР МИХАЙЛОВИЧ

    2016-01-01

    Исследована взаимосвязь между последовательностью превращений «аморфная фаза → метастабильный кристаллический твёрдый раствор → стабильный кристаллический твёрдый раствор» в наноразмерных прекурсорах итоговых составов ZrO2, 5СaO-95ZrO2 и 9СaO-91ZrO2, полученных криохимическими методами. Было установлено, что кинетическая стабилизация метастабильных фаз в требуемом температурно-концентрационном интервале может быть достигнута за счёт корректного выбора метода обработки гелей, полученных золь-г...