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Sample records for caesium

  1. Determination of caesium-137 in liquid milk

    International Nuclear Information System (INIS)

    Jankowska, S.

    1969-01-01

    A technique for determining caesium-137 in milk on the basis of caesium-137 sorption has been adapted according to the method of Broadbank. The caesium carrier is not added, because its addition decreases the sensitivity of measurement. Two procedures were used for the assay of caesium-137 in milk: (a) Sorption of caesium-137 from the solution of milk ash dissolved in 3M HNO 3 ; (b) Sorption of caesium-137 from whey. In both methods the radioactivity of caesium-137 was determined directly on the ammonium molybdophosphate (AMP) bed by means of counting

  2. Structure of caesium selenate

    International Nuclear Information System (INIS)

    Zuniga, F.J.; Breczewski, T.; Arnaiz, A.

    1991-01-01

    Cs 2 SeO 4 , M 4 =408.77, orthorhombic, Pnam, a=8.3777 (8), b=11.276 (2), c=6.434 (2) A, V=607.8 (2) A 3 , Z=4, D x =4.46 Mg m -3 , MoKα, λ=0.71069 A, μ=185.06 cm -1 , F(000)=704, T=293 K, R=0.048, 3348 observed reflections. Average values of the Se-O and Cs-O distances are 1.637 (4) and 3.387 (3) A, respectively [range 3.038 (5)-3.872 (6) A with 9 and 11 coordination of caesium by oxygen]. (orig.)

  3. Human metabolism of caesium

    International Nuclear Information System (INIS)

    Raeaef, C.L.; Falk, R.; Lauridsen, Bente; Rahola, T.; Soogard-Hansen, J.

    2006-04-01

    A study of the human biokinetics of caesium in two forms, i.) incorporated in foodstuff (137Cs in perch and mushrooms) and ii.) in ionic state ( 134 Cs in aqueous solution) has been carried out at the department of Radiation Physics in Malmoe, starting in 2001. The results of the pilot study were published in 2004, and a continuation of that study has now been carried out by means of NKS funding (NKS-B Cskinetik). The aim is to, i.) investigate whether Scandinavian populations exhibit shorter biological half-time of radiocaesium than other populations; ii.) extend the biokinetic study to additional human subjects from the other Nordic countries. Results from the continued study further indicate a near complete absorption of radiocaesium in the gastro-intestinal tract, be it in ion state or contained in food matrix. So far, the literature survey of Nordic studies on biokinetics of Cs suggests that the biological half time is somewhat shorter among Scandinavian males (84 days vs. ICRP-value of 110 days), although females do not exhibit any significant difference (64 days vs ICRP value of 65 days). (au)

  4. Human metabolism of caesium

    Energy Technology Data Exchange (ETDEWEB)

    Raeaef, C.L. [Lund Univ., Dept. of Radiation Physics in Malmoe (Sweden); Falk, R. [Swedish Radiation Protection Authority (Sweden); Lauridsen, Bente [Risoe National Lab. (Denmark); Rahola, T. [STUK - Radiation and Nuclear Safety Authority (Finland); Soogard-Hansen, J. [NRPA - Norwegian Radiation Protection Authority (Norway)

    2006-04-15

    A study of the human biokinetics of caesium in two forms, i.) incorporated in foodstuff (137Cs in perch and mushrooms) and ii.) in ionic state ({sup 134}Cs in aqueous solution) has been carried out at the department of Radiation Physics in Malmoe, starting in 2001. The results of the pilot study were published in 2004, and a continuation of that study has now been carried out by means of NKS funding (NKS-B Cskinetik). The aim is to, i.) investigate whether Scandinavian populations exhibit shorter biological half-time of radiocaesium than other populations; ii.) extend the biokinetic study to additional human subjects from the other Nordic countries. Results from the continued study further indicate a near complete absorption of radiocaesium in the gastro-intestinal tract, be it in ion state or contained in food matrix. So far, the literature survey of Nordic studies on biokinetics of Cs suggests that the biological half time is somewhat shorter among Scandinavian males (84 days vs. ICRP-value of 110 days), although females do not exhibit any significant difference (64 days vs ICRP value of 65 days). (au)

  5. Formulation of caesium based and caesium containing geo-polymers

    Energy Technology Data Exchange (ETDEWEB)

    Berger, S.; Joussot-Dubien, C.; Frizon, F. [CEA Valrho, Dir. de l' Energie Nucleaire, DEN, Decontamination and Conditioning Department, DEN/DTCD/SPDE/L2ED, 30 - Marcoule (France)

    2009-10-15

    Cement encapsulation is widely used as a low- and intermediate level radioactive waste immobilisation process. Among these wastes, caesium ions are poorly immobilised by Portland cement based materials. This work consists of an experimental investigation into the ability of geo-polymers to effectively encapsulate this chemical species and to determine the impact of caesium incorporation on the geo-polymer properties. Geo-polymers were synthesised with several compositions based on the activation of metakaolin with an alkali hydroxide solution containing caesium. The setting time, mineralogy, porosity and mechanical properties of the samples were examined for one month. Leach tests were conducted during the same period to determine the immobilisation efficiency. The results depend to a large extent on the composition of the activation solution in terms of soluble silica content and alkali used. These parameters determine both the degree of condensation and the geo-polymer composition. (authors)

  6. Formulation of caesium based and caesium containing geo-polymers

    International Nuclear Information System (INIS)

    Berger, S.; Joussot-Dubien, C.; Frizon, F.

    2009-01-01

    Cement encapsulation is widely used as a low- and intermediate level radioactive waste immobilisation process. Among these wastes, caesium ions are poorly immobilised by Portland cement based materials. This work consists of an experimental investigation into the ability of geo-polymers to effectively encapsulate this chemical species and to determine the impact of caesium incorporation on the geo-polymer properties. Geo-polymers were synthesised with several compositions based on the activation of metakaolin with an alkali hydroxide solution containing caesium. The setting time, mineralogy, porosity and mechanical properties of the samples were examined for one month. Leach tests were conducted during the same period to determine the immobilisation efficiency. The results depend to a large extent on the composition of the activation solution in terms of soluble silica content and alkali used. These parameters determine both the degree of condensation and the geo-polymer composition. (authors)

  7. Theoretical melting curve of caesium

    International Nuclear Information System (INIS)

    Simozar, S.; Girifalco, L.A.; Pennsylvania Univ., Philadelphia

    1983-01-01

    A statistical-mechanical model is developed to account for the complex melting curve of caesium. The model assumes the existence of three different species of caesium defined by three different electronic states. On the basis of this model, the free energy of melting and the melting curve are computed up to 60 kbar, using the solid-state data and the initial slope of the fusion curve as input parameters. The calculated phase diagram agrees with experiment to within the experimental error. Other thermodynamic properties including the entropy and volume of melting were also computed, and they agree with experiment. Since the theory requires only one adjustable constant, this is taken as strong evidence that the three-species model is satisfactory for caesium. (author)

  8. Leakage of caesium braquitherapy sources

    International Nuclear Information System (INIS)

    Lozada, J.A.

    1998-01-01

    In several Venezuelan public hospitals where cervix uteri tumours are treated by intracavitary radiotherapy, that use manual after loading Fletcher method, with Caesium 137 sources, the use of improper source holders, locally manufactured from pieces of drainage plastic tubing, which deteriorated and created a corrosive environment all around the sources, omission of manufacturer's recommendations regarding corrosion information, source storage, inspection and testing, violation of International Atomic Energy Agency Radiation Protection Procedures, and lack of proper regulatory control, resulted integrity damage to about sixty special form sources (ISO2919 C 63322), leakage of Cs-137 from a supposed insoluble refractory active content (caesium silicoaluminate), and contamination of applicators, floors and bedding. When the situation was detected by means removal contamination tests, after routine inspections, the sources were removed from the hospitals, decontaminated by means of immersion in 3% EDTA solution in ultrasonic bath, subjected to leaking assessment tests, and the ones that passed were placed in low cost stainless steel source holders, designed and built by the instituto Venezolano de Investigaciones Cientificas (IVIC) returned to the hospitals. The leaking sources were removed from use and considered radioactive waste. In order to avoid the occurrence of similar situations, all the importers of such sources are now required to send them to IVIC for testing and placement in proper source holders, before they are shipped to the hospitals. (author)

  9. Vapour pressure of caesium over nuclear graphite

    International Nuclear Information System (INIS)

    Faircloth, R.L.; Pummery, F.C.W.

    1976-01-01

    The vapour pressure of caesium over a fine-grained isotropic moulded gilsocarbon nuclear graphite intended for use in the manufacture of fuel tubes for the high temperature reactor has been determined as a function of temperature and concentration by means of the Knudsen effusion technique. The concentration range 0 to 10 μg caesium/g graphite was investigated and it was concluded that a Langmuir adsorption situation exists under these conditions. (author)

  10. The New PTB Caesium Fountain Clock CSF2

    National Research Council Canada - National Science Library

    Wynands, R; Bauch, A; Griebsch, D; Schroeder, R; Weyers, S

    2005-01-01

    At PTB a second caesium fountain clock, CSF2, is in the process of being set up. It differs from the first PTB caesium fountain standard CSF1 in a number of details, which are consecutively specified...

  11. Separation of caesium-137 from fission products using phosphotungstic acid

    International Nuclear Information System (INIS)

    Murthy, T.S.; Balasubramaniam, K.R.; Ananthakrishnan, M.; Varma, R.N.

    1977-01-01

    Separation of caesium 137 from fission products using phosphotungstic acid is reported. Phosphotungstate caesium is precipitated as caesium from fission product waste solution in acid medium and subsequently purified. Separation of phosphate and tungstate ions has been done using a typical hydrous oxide like alumina. The exchange capacity of alumina for phosphate and tungstate ions, and the purity of the product are determined. Results are discussed. Based on the findings a procedure is recommended for caesium 137 separation. (A.K.)

  12. Phonon dispersion relations for caesium thiocyanate

    International Nuclear Information System (INIS)

    Irving, M.A.; Smith, T.F.; Elcombe, M.M.

    1984-01-01

    Room temperature phonon dispersion relations for frequencies below 2 THz have been measured, along the three orthorhombic axes and selected diagonal directions by neutron inelastic scattering, for caesium thiocyanate. These curves, which represent 13 acoustic modes and 11 optic modes of vibration, do not agree with the dispersion behaviour calculated from the rigid-ion model developed by Ti and Ra to describe their Raman scattering observations

  13. Caesium contamination in human milk and transfer factor from diet

    International Nuclear Information System (INIS)

    Risica, S.; Campos Venuti, G.; Rogani, A.; Baronciani, D.; Petrone, M.

    1992-01-01

    A study on caesium contamination in human milk, as a consequence of the Chernobyl fallout, was conducted in 1989 on a group of women from one of the areas of northern Italy most heavily affected by the radioactive fallout. Their diet was studied, and the caesium intake was calculated by using the mean food activity concentration in that area. The caesium transfer factor was evaluated both as the ratio of caesium concentration in mother's milk to the daily intake, and by using a simplified milk compartment model. (author)

  14. Positron scattering by rubidium and caesium

    International Nuclear Information System (INIS)

    Kernoghan, A.A.; Walters, H.R.J.; McAlinden, M.T.

    1996-01-01

    We report results in the energy range 0.5 to 64 eV for positron scattering by ground state rubidium and caesium in Ps(1s,2s,2p,3s,3p,3d) + Rb(5s,5p,6s,6p,4d) and Ps(1s,2s,2p,3s,3p,3d) + Cs(6s,6p,7s,7p,5d) coupled-state approximations, respectively. The pattern of results is similar to analogous calculations made on potassium by McAlinden et al. Except at the lowest energies, positronium formation is found to be almost entirely into excited states, with there being a dramatic collapse of the Ps(1s) cross section in the case of caesium. Ps(n = 2), Ps(n = 3) and Ps(n≥ 4) cross sections are predicted to be of comparable size. Ps(n≥ 4) formation is estimated from the calculated Ps(n = 3) results using the n 3 scaling rule. Good agreement in shape and magnitude is obtained with the recent lower bound measurements of total positronium formation in rubidium by Surdutovich et al, although there are differences in detail. Good agreement is also achieved with the total cross section measurements of Parikh et al on rubidium after these have been corrected for discrimination against forward elastic scattering and renormalized upwards by 5%. These total cross section measurements display a pronounced peak near 6 eV which is well reproduced by the present theory but is at variance with the earlier Rb(5s,5p,6s,6p,4d) calculations of McEachran et al which neglect positronium formation. This peak, which also appears in the calculations on potassium and caesium, is primarily associated with the maximum in the total positronium formation cross section. At low energies elastic scattering is dominant, this dominance being directly taken over by the resonance excitation of the atom with increasing impact energy. The next most important cross section is positronium formation, followed by excitation of the lowest atomic d-state. The 5s → 6s and 5s → 6p transitions in rubidium and the 6s → 7s and 6s → 7p transitions in caesium are of relatively minor importance. (Author)

  15. Laser spectroscopy of collisionally prepared target species: atomic caesium

    International Nuclear Information System (INIS)

    Moreau, J.-P.; Tremblay, Julien; Knystautas, E.J.; Laperriere, S.C.; Larzilliere, Michel

    1989-01-01

    Fast ion beam bombardment was used to collisionally prepare a target gas in excited states, to which conventional laser spectroscopy was then applied. The versatility of this method is demonstrated with atomic targets of caesium, for a state of Cs + that is 16 eV above the ground state, as well as for a short-lived state (38 ns) of the neutral atom. The local temperature in the caesium oven is also obtained. (Author)

  16. Correlation of erosion and erodibility assessments using caesium-137

    International Nuclear Information System (INIS)

    Elliott, G.L.; Campbell, B.L.; Loughran, R.J.

    1984-01-01

    Data are presented which show that in soils in which net erosion is occurring, the content of the environmental isotope caesium-137 is highly correlated with soil loss. Other soil characteristics which may be related to the caesium content and therefore to soil loss have also been examined. Of these factors, an improved index of soil aggregate stability explained the most variation in caesium content (52%). Soil organic matter content explained 27% of variation in caesium content and other soil erodibility indices based on quantitative measurement of aggregate stability, explained between 6% and 21% of the variation. Indices based on implied hydrologic characteristics, implied aggregation and clay dispersion explained between 1% and 3% of caesium variation. It is suggested that practical factors of soil protection are relevant to the prediction of erosion hazard and may be more relevant than some indices of soil resistance. It is noted further that caesium-137 content of a soil gives every indication of being a most suitable predictor of soil erosion status

  17. Caesium fallout as a tracer of erosion-sedimentation

    International Nuclear Information System (INIS)

    Bouhlassa, S.; Azenfar, A.; Machrouh, A.

    1994-01-01

    The purpose of this paper is to set up a methodology of use of radioactive caesium fallout, to measure erosion and sedimentation in a sub-catchment and to establish the effects of geomorphological parameters, land uses and soil nature, on the losses caesium by physical process. The result obtained by this new and elegant approach, on a watershed of 4114 ha., studied before by classical and conventional techniques, gives a good evaluation of erosion, but also sedimentation rate, and permit to stand up, a model and sampling strategy, to extend the method to large catchment. 1 tab., 2 refs. (author)

  18. Experimental studies of caesium iodide aerosol condensation: theoretical interpretation

    International Nuclear Information System (INIS)

    Beard, A.M.; Benson, C.G.; Horton, K.D.; Buckle, E.R.

    1990-07-01

    Caesium iodide is predicted to be a significant source of fission product aerosols during the course of a severe accident in a pressurised water reactor (PWR). The nucleation and growth of caesium iodide aerosols have been studied using a plume chamber and the results compared with theoretical values calculated using the approach developed by Buckle for aerosol nucleation. The morphology of the particles was studied using scanning electron microscopy (SEM) and transmission optical microscopy (TOM), whilst the particle size distributions were determined from differential mobility (DMPS) and aerodynamic (APS) measurements. (author)

  19. Translocation of the radioactive caesium via the calyx in persimmon fruit

    International Nuclear Information System (INIS)

    Sekizawa, Haruhito; Sato, Mari; Aihara, Takashi; Murakami, Toshifumi; Hachinohe, Mayumi; Hamamatsu, Shioka

    2016-01-01

    To elucidate pathways of radioactive caesium contamination of persimmon fruit, we investigated translocation via the calyx. We treated calyces of immature and mature fruits (at either stage and both stages) with water containing caesium-137 (1000 Bq/kg) and measured concentrations in the calyx, pericarp, and flesh with a germanium semiconductor detector. All treated fruits had higher levels of radioactive caesium in all tissues than untreated fruits at harvest. The translocated radioactive caesium was retained in the fruit and not retranslocated. These results indicate that radioactive caesium is translocated via the calyx of persimmon at all stages of fruit development and is accumulated in the flesh. (author)

  20. The mechanisms of caesium uptake by plants

    International Nuclear Information System (INIS)

    White, P.; Bowen, H.; Broadley, M.; Hammond, J.; Hampton, C.; Payne, K.

    2004-01-01

    Persistent radioactive isotopes of caesium ( 134 Cs and 137 Cs) in the environment are of concern because they impact on both health and commerce. They enter the terrestrial food chain through plants. Plant roots take up Cs + from the soil solution. To reach the shoot via the xylem, Cs + must cross the plasma membranes of root cells at least twice. This is catalysed by transport proteins. Since Cs is an alkali metal with chemical properties similar to potassium (K), it has been suggested that the same proteins that transport K + also transport Cs + . However, the Cs:K ratio in the shoots of different plant species grown under identical conditions varies widely. Since different transport proteins have contrasting abilities to discriminate between Cs + and K + , this varying Cs:K ratio suggests that a different complement of transport proteins operates in different plant species. In the plasma membrane of root cells inward-rectifying K + channels (KIRCs), outward-rectifying cation channels (KORCs and NORCs), voltage-independent cation channels (VICCs) and voltage-dependent Ca 2+ channels (HACCs and DACCs) are all permeable to Cs + and K + . In addition, the 'high-affinity' K + /H + symporters (KUPs) and 'low affinity' transporters, such as the wheat TaLCT1 protein, may also transport Cs + and K + . The relative abundance and selectivity of these transport proteins in the root plasma membrane will determine the relative fluxes of Cs + and K + to the shoot. Theoretical models describing Cs + fluxes across the plasma membrane of root cells predict that, under natural conditions, VICCs mediate most (30 to 90%) of the Cs + influx, with KUPs mediating the remainder, Cs + influx through KIRCs is negligible, and stelar KORCs load Cs + into the xylem. These predictions are consistent with the identical pharmacology of VICCs and Cs + uptake by plants, which are both partially inhibited by La 3+ , Ba 2+ or Ca 2+ at millimolar concentrations, and the phenotypes of Arabidopsis

  1. New Composite Sorbents for Caesium and Strontium Ions Sorption

    Directory of Open Access Journals (Sweden)

    Mykola Kartel

    2017-06-01

    Full Text Available Composite lignocellulose-inorganic sorbents derived from plant residues of agriculture and food industry, modified with ferrocyanides of d-metals and hydrated antimony pentoxide were prepared. Caesium and strontium ions removal from water was tested by radiotracer method. Sorption of heavy metal ions, methylene blue, gelatin, vitamin B12 was also studied.

  2. Low Level Caesium Mapping in Latvia Anno 1996

    DEFF Research Database (Denmark)

    Aage, Helle Karina

    1999-01-01

    In Latvia the caesium-137 contamination from the Chernobyl accident and from the nuclear weapon tests in the 1960´es is very low. Conventional techniques for extracting information from the measured spectra cannot be used here. Therefore a new, sensitive technique - the pseudo concentration method...

  3. Low Level Caesium Mapping in Latvia Anno 1995

    DEFF Research Database (Denmark)

    Aage, Helle Karina

    1999-01-01

    In Latvia the caesium-137 contamination from the Chernobyl accident and from the nuclear weapon tests in the 1960´es is very low. Conventional techniques for extracting information from the measured spectra cannot be used here. Therefore a new, sensitive technique - the pseudo concentration method...

  4. Elements of reflection on pathologies possibly induced by caesium 137

    International Nuclear Information System (INIS)

    Nifenecker, Herve

    2006-01-01

    The author discusses the content of few known publications on the possible pathological effects of caesium 137: a Belarus study on the consequences of Chernobyl, results of few autopsies performed on babies and adults, a study performed on rats, and a study performed on a set of 94 children in a sanatorium

  5. The caesium oxygen interactions in the crystalline solids

    International Nuclear Information System (INIS)

    Leclaire, Andre

    2008-01-01

    Through the study of the Cs-O bonds registered in the literature one observes that: (i)the bond lengths range from 2.46 to 3.60 A; (ii)the preferential coordination numbers adopted by the caesium ions are 8, 9 and 10 but values from 1 to 12 also exist; (iii)the average bond lengths increase with the coordination (CN) of the caesium ions with the following values: 2.714 A (CN=1), 2.98 A (CN=2), 3.057 A (CN=3), 3.104 A (CN=4), 3.149 A (CN=5), 3.188 A (CN=6), 3.224 A (CN=7), 3.245 A (CN=8), 3.261 A (CN=9), 3.269 A (CN=10), 3.293 A (CN=11) and 3.323 A (CN=12). A new R ij =2.469 constant is determined with all the caesium coordination polyhedra to compute electrostatic bond valence sums. The U eq values of caesium in crystal structure are about 0.03 and generally less than 0.06 similar to those of the oxygen atoms and often bigger. - Graphical abstract: A survey of more than 1000 of oxygen polyhedrons around caesium ions shows bond lengths ranging from 2.46 to 3.60 A with 32% of the shortest bonds in the polyhedrons less than 3.00 A. Coordination numbers from 1 to 12 are observed, in which the average bond lengths increase from 2.714 to 3.323 A with the coordination, and with a preference for 8, 9 and 10-fold surrounding

  6. Investigation of the elution by seawater of caesium and strontium from loaded clinoptilolite

    International Nuclear Information System (INIS)

    Harder, B.R.; Mitchell, I.H.; Smyth, M.J.

    1985-07-01

    Simple investigations of the elution of caesium and strontium from loaded clinoptilolite are described. The clinoptilolite was loaded to levels expected in the British Nuclear Fuels plc SIXEP plant and contacted with seawater at approx. 15 C. (The elution time was measured until about 99% of the caesium and strontium had been eluted.) It was found that 99% of the caesium was eluted in 35 hours but the strontium (with more variable results) took at least 400 hours for 99% elution. (author)

  7. Reduction of radioactive caesium in meat and fish by soaking

    International Nuclear Information System (INIS)

    Petaejae, E.; Puolanne, E.

    1992-01-01

    The removal of radioactive caesium from meat by soaking in brine or water and the effect of injection curing, temperature, size of meat piece and cooking on this removal were studied. The availability of the brined meat for the manufacture of cured, smoked and cooked meat, oven-cooked meat and cooked sausages was also investigated. The soaking method was also tested on fish. (Author)

  8. Evaluation of caesium atomic fountain NICT-CsF1

    International Nuclear Information System (INIS)

    Kumagai, M.; Ito, H.; Kajita, M.; Hosokawa, M.

    2008-01-01

    In this paper, we describe the first caesium atomic fountain primary frequency standard NICT-CsF1 of National Institute of Information Communications Technology (NICT) in Tokyo, Japan. The structure of the NICT-CsF1 system and evaluation procedure of the systematic frequency shifts and their uncertainties are presented. Typically, NICT-CsF1 has a frequency stability of 4 * 10 -13 /τ 1/2 and a frequency uncertainty of 1.9 * 10 -15 . (authors)

  9. The behaviour of radioactive caesium in a boreal forest ecosystem

    International Nuclear Information System (INIS)

    Bergman, R.; Nylen, T.; Lidstroem, K.; Palo, T.

    1991-01-01

    The distribution of radioactive caesium (Cs-134 and Cs-137) in a boreal forest ecosystem is studied with focus in the dynamics of the turnover in, and loss from, the system. Measurements of the distribution in soil and vegetation, as well as the loss of radioactive caesium by run-off from a catchment, constitute the basis for an analysis of the caesium budget in the system. Comparisons of the distribution of 'old' Cs-137, i.e. originating from fallout due to the atmospheric nuclear weapons test, and that due to deposition after the accident in Chernobyl 1986 are used for extrapolations to future situations concerning transport of Cs-137 via the food chains over berries and moose to man. The exposure in a long term perspective due to the average intake of Cs-137 in the Swedish population by consumption of meat, milk, and milk products (i.e. of an agricultural origin) is compared to that due to ingestion of the forest products: berries (bilberry, lingonberries, and cloudberries) and moose meat. (au) (34 refs.)

  10. Caesium absorption by barley - influence of its retention by the soil - competitive action of potassium

    International Nuclear Information System (INIS)

    Ferron-Trosseau, F.

    1964-06-01

    We have studied, in various culture media, how the absorption of caesium by barley varies with its concentration, and how this absorption can be in competition with a similar alkali cation-potassium. We have also considered the caesium distribution in the ground in particular radio-active caesium, between the soil and solution, as a function of the amount of caesium. From our work it is clear that barley behaves very differently according to whether the caesium is in a nutritive solution or is in the soil: for a nutritive solution, the fraction of caesium (radioactive and stable) absorbed by barley remains practically constant in the presence of increasing amounts (relatively small) of stable caesium; in soil, the fraction of the radio-active caesium absorbed increases as the stable caesium content (fairly low) of the soil increases, in relationship with a rapidly decreasing selectivity of the soil for Cs + . The difference between these results is thus explained by the very pronounced selectivity of the illitic soil studied for Cs + , as long as the proportion of Cs remains low, about as low as that of most natural soils. Furthermore, the K + ion is in competition with the Cs + ion, for absorption by barley in a culture medium in a nutritive solution or in soil, only when the potassium concentrations are relatively low, of the order of the nutritive maximum. This shows that the addition of potassium to a medium already rich in this element does not reduce the absorption of caesium by barley. The choice of experimental conditions close to natural conditions (nutritive media strong in calcium) and the examination of the distribution of radioactive caesium between the soil, the soil solution and the plant in the presence of very low doses of stable caesium make these results interesting from the 'atomic health' point of view; it should be expected that a definite contamination risk exists for plants cultivated on synthetic media and for plants such as rice and cress

  11. Uptake Evaluation Of Glass house Grown Grasses In Radio phyto remediation Of Caesium-Contaminated Soil

    International Nuclear Information System (INIS)

    Zal U'yun Wan Mahmood; Nur Humaira' Lau Abdullah; Khairuddin Abdul Rahim

    2014-01-01

    A glass house experiment was performed to evaluate the uptake of grasses viz. Napier and Vetiver in radiophytoremediation of caesium-contaminated soil. The glass house radiophytoremediation experiment was designed according to the Randomized Complete Block Design (RCBD). The grasses were grown in troughs filled with soil mixed with a known specific activity of 134 Cs. Initial Cs activity and activity after different cultivation time intervals of 1, 3, 6 and 9 months were analyzed using gamma spectrometer direct measurement. The results showed the uptake of caesium by Napier and Vetiver after 9 months with the transfer factors (TF) were 4.70 and 6.25, respectively. Meanwhile, the remediation of caesium from contaminated soil at the same time was 95.25 % (Napier) and 95.58 % (Vetiver). Both grasses have been found to accumulate caesium, with Vetiver accumulating higher than Napier. Thus, the present study suggests that Vetiver could be used as a potential plant for radiophytoremediation of caesium. (author)

  12. NIFSIL - a composite sorbent for caesium - properties and application

    International Nuclear Information System (INIS)

    Rajec, P.; Orechovska, J.

    1998-01-01

    Samples of the potassium-nickel ferrocyanides K 2 NiFe(CN) 6 , KNi 1,5 Fe(CN) 6 and Ni 2 Fe(CN) 6 were prepared and their properties studied with respect to their use as sorbents for caesium. Caesium is fixed on mixed alkaline-nickel ferrocyanide without structural change. The capacity of Cs retention never reached the theoretic value corresponding to a total release of the monovalent ions of the solid. High distribution coefficients (K D in the order of 10 4 cm 3 /g) determined in batch experiments show that these sorbents have a very high affinity for caesium ions, even in the presence of competing K + , Na + and Ca 2+ ions. The sorbents have a good chemical stability in a wide pH-range (2-12). The irradiation of some sorbent samples with high energy gamma-rays ( 60 Co) of a total dose of 1.10 5 Gy caused no remarkable changes in the sorbent properties (K D , sorption capacity and kinetics, mechanical stability). The sorbents were also tested for 85 Sr and 239 Pu and the results carried out under dynamic and batch experiments have shown that sorbents are not suitable for removal of these radionuclides. Potassium nickel hexacyanoferrate incorporated in silica-gel matrix could compete with others sorbents based on insoluble hexacyanoferrates, has the advantage of good radiation stability and suitable granulometry. The sorbent was prepared on a pilot scale with a capacity about 1000 kg per year with the prospect that it could be easily upgraded to an industrial scale

  13. The removal of caesium ions using supported clinoptilolite

    International Nuclear Information System (INIS)

    De Haro-Del Rio, D.A.; Al-Joubori, S.; Kontogiannis, O.; Papadatos-Gigantes, D.; Ajayi, O.; Li, C.; Holmes, S.M.

    2015-01-01

    Highlights: • Natural clinoptilolite was supported over carbon structures produced from wastes. • Carbon–clinoptilolite showed an improved Cs + ions sorption capacity. • Overall kinetic rate was improved using carbon–clinoptilolite composite. • Diffusive resistances were modified using the composite and pure zeolite. • Final disposition volume can be reduced up to 60% by encapsulation. - Abstract: In this paper, the sorptive kinetic and diffusional characteristics of caesium ion removal from aqueous solution by carbon-supported clinoptilolite composites are presented. Natural clinoptilolite was supported on carbonaceous scaffolds prepared from date stones. Thermal treatment was applied to produce voids in the carbon which was conditioned using polydiallyldimethylammonium chloride to facilitate the clinoptilolite attachment. This method allowed the formation of a consistent zeolite layer on the carbon surface. The composite was applied in the removal of non-radioactive caesium ions showing an enhanced uptake from 55 mg g −1 to 120.9 mg g −1 when compared to clinoptilolite. Kinetic studies using Pseudo First Order model revealed an enhanced rate constant for carbon–clinoptilolite (0.0252 min −1 ) in comparison with clinoptilolite (0.0189 min −1 ). The Pseudo-First Order model described the process for carbon–clinoptilolite, meanwhile Pseudo Second Order model adjusted better for pure clinoptilolite. Diffusivity results suggested that mass transfer resistances involved in the Cs + sorption are film and intraparticle diffusion for natural clinoptilolite and intraparticle diffusion as the mechanism that controls the process for carbon–clinoptilolite composite. The most significant aspect being that the vitrified volume waste can be reduced by over 60% for encapsulation of the same quantity of caesium due to the enhanced uptake of zeolite

  14. Thermogravimetric analysis and dissociation pressure of caesium trihalides

    International Nuclear Information System (INIS)

    Harris, G.S.; McKechnie, J.S.

    1982-01-01

    We have carried out a thermogravimetric study of caesium trihalides to obtain, from the procedural decomposition temperatures, an order of apparent thermal stability which could be compared with the order of thermodynamic stability obtained from vapour pressure measurements. Thermogravimetric analysis could also prove to be a useful method for rapid analysis of metal polyhalides. The thermograms indicated a one-step decomposition for each compound; the procedural decomposition temperatures and percentage weight losses obtained are given. Dissociation pressures were measured and values of equilibrium constant and enthalpy of dissociation were calculated. The results are given. The 'stability' order obtained is discussed. (U.K.)

  15. Behaviour of caesium-137 in the marine environment

    International Nuclear Information System (INIS)

    Gilat, E.; Laichter, Y.; Shafrir, N.H.

    1975-01-01

    The radiological impacts of radioactive release from nuclear facilities into aquatic environments can be studied by following the behaviour of fallout radionuclides in the sea, provided that they exist in the same physico-chemical state. Caesium-137 entering the sea from fallout, although found to be at extremely low levels in the marine environment, is still detectable and can be considered representative for the behaviour of 137 Cs appearing in cooling waters and effluents of nuclear installations and processing plants located near the sea. The relatively high radiotoxicity, long physical half-life and high fission yield of 137 Cs justify further investigation of its behaviour in aquatic environments. In this investigation the sampling of sea water, sediments and organisms in the Mediterranean Sea was undertaken. Caesium-137 determinations were carried out using an extremely low level Ge(Li) gamma spectrometry system specifically designed for studies of environmental marine radioactivity. The activity of 137 Cs on the surface of the sea was found to be 0.49+-0.17 pCi/1. Caesium-137 concentrations at depth profiles down to 1000 m below the surface show variations by a factor of ten (0.65-0.07), maximum concentrations being found at a depth of 100-300 m. These concentration peaks may be explained by good mixing in the upper layers and by the existence of a thermocline or pycnocline which serve as mixing barriers at depths down to approximately 300 m, at least during part of the year. Caesium-137 concentrations in a number of marine biota representing a marine food chain composed of benthic algae, invertebrates and fishes, were determined. With reference to the average 137 Cs content in the upper water layers of the sea, concentration factors for these organisms were calculated. In all the three taxonomic groups mentioned, values within the range 10-300 were found. Biological concentration factors for any particular radionuclide are independent of its content in the

  16. Chemical stability and physical properties of Caesium uranates

    International Nuclear Information System (INIS)

    Berton, J.P.; Baron, D.; Coquerelle, M.

    1998-01-01

    Caesium is one of the most abundant fission products in PWR nuclear fuel or in fast reactor fuel as well. A work program has been started at the TUI Karlsruhe, in collaboration with EDF Etudes et Recherches, to determine the thermal stability and conductivity, the mechanical properties and the thermal expansion coefficient of Cs 2 UO 4 . The Caesium mono-uranate was obtained by a chemical reaction between Cs 2 O 3 and U 3 O 8 powders mixed together, pressed and heated at 670 deg. C for 24 hours. The compound was found stable up to 830 deg. C. Mechanical compressive hardening tests allowed to evaluate the elastic modulus versus temperature in the range 200 to 800 deg. C. Furthermore the viscous behaviour of the compound above 400 deg. C was confirmed. The thermal expansion coefficient of Cs 2 UO 4 was found somewhat 40% higher than the thermal expansion coefficient of UO 2 . The thermal conductivity is about 1.5 to 1.8 W/m/K for temperatures ranging from 100 to 700 deg. C, a value very similar to the UO 2 fuel thermal conductivity at high burnup in the same temperature range. (author)

  17. Caesium transfer to placenta, urine and human milk

    International Nuclear Information System (INIS)

    Risica, S.; Rogani, A.; Tancredi, F.; Grisanti, A.; Grisanti, G.; Baronciani, D.; Del Prete, A.; Zanini, R.

    1997-01-01

    After the Chernobyl accident few measurements on radioactive contamination of maternal milk, placenta and urine of nursing mothers were carried out. Two previous studies on breast milk contamination were conducted in different Italian areas by the Physics Department of the National Institute of Health (Laboratorio di Fisica, Istituto Superiore di Sanita). In the first study conducted in collaboration with the Epidemiological Unit of the Lazio District, I-131, Cs-134 and Cs-137 concentrations were measured in mixed breast milk samples pooled from 5-10 women in the first week after delivery, from May 1986 to December 1987, in the Rome area. The second research was conducted, in collaboration with the Lecco Hospital, in 1989 on a group of women living in the Como Lake area (Lombardia), which was one of the areas of Northern Italy most heavily affected by Chernobyl fallout, because of intensive rainfall in the first few days after the accident. The specific diet and caesium content in maternal milk were studied recruiting pregnant women at the ''respiratory autogen training'' course. In this case, Cs-l37, Cs-134 and K-40 concentration in placenta and urine of the mothers under study had also been measured. Aim of this paper is to discuss these data and investigate the relationship between Cs-137 contamination of maternal milk, placenta and urine as a contribution to a better understanding of caesium metabolism in pregnant and nursing women

  18. Behavioural Changes in Rats Internally Contaminated with Caesium-137

    International Nuclear Information System (INIS)

    Ramboiu, S.

    2001-01-01

    Full text: The effect of low doses of 137 Cs on the exercise performances, behavioural and learning processes in rats is analysed. The experiments were performed on albino male and female Wistar rats. The animals were divided as follows: two groups, M 1 and F 1 (males and females) internally contaminated with 490 Bq 137 Cs by milk ingestion during 34 days, groups M 2 and F 2 , internally contaminated with 283 Bq by ingestion of milk during 38 days and two control groups. The duration of forced swimming, the active avoidance reaction and the total latency time in the shuttle-box and the score of aggressive behaviour were analysed. The following results were obtained: (1) the duration of forced swimming decreased significantly in the contaminated groups as compared with controls. (2) The active avoidance reaction in the shuttle-box increased in female groups and decrease in male groups. (3) The total latency time of the same reaction was lower in animals internally contaminated with 137 Cs in the first day of learning. (4) The score of aggressive behavioural rise significantly, especially in female groups. The results can be explained by neurotoxic action of the caesium on several central neural areas including monoaminergic and endocrine mechanisms and sex dependence of caesium accumulation in the organism. (author)

  19. New selective ligands for caesium. Application to Cs+/Na+ separation by nano-filtration-complexation in aqueous phase

    International Nuclear Information System (INIS)

    Pellet-Rostaing, S.; Chitry, F.; Lemaire, M.; Guy, A.; Foos, J.

    2000-01-01

    Separating traces of caesium from aqueous medium containing high sodium concentration is a harsh problem because caesium and sodium have a similar behaviour in aqueous medium. The aim of our study was to select a highly caesium-selective ligand in a nano-filtration-complexation process in order to achieve Cs + /Na + separation. This process involve a nano-filtration step combined with a preliminary complexation step. Caesium complexes are retained by the nano-filtration membrane whereas free sodium cations pass through it. We tried to find a relation between the ligands structure and their activity towards caesium-complexation. Among the synthesized receptors, Tetra-hydroxylated bis-crown-6 calix[4]arene was found to be the more caesium-selective ligand (S=β(Cs + )/β(Na+)=6600). Combined with a nano-filtration process, this ligand helped reaching 90% caesium retention in a highly concentrated aqueous medium ([NaNO 3 ] = 3 mol/L). (authors)

  20. Prepubertal changes in the metabolism of caesium in girls?

    International Nuclear Information System (INIS)

    Rundo, J.

    1987-01-01

    The results are presented of determinations from 1963 to 1967 of the 137 Cs/K ratio in three children (two girls and a younger boy). In the two girls the ratio was at a maximum in late 1963. The decline by a factor of more than four during 1965-1967 was consistent with the contemporaneous reduction in dietary contamination. When adjusted to allow for the decreasing intake, the ratio shows an increase from the age of about 9.5 in each girl. It is suggested that this is a reflection of an increase in the biological half-life of caesium in the girls, associated with prepubertal hormonal changes. 5 refs.; 4 figs.; 2 tabs

  1. Contribution to the use in analysis of ammonium phosphomolybdate- separation of radio-caesium in solution

    International Nuclear Information System (INIS)

    Scheidhauer, J.; Chabidon, M.; Ordinaire, L.

    1964-01-01

    The use in analysis of ammonium phosphomolybdate has been studied for the separation of barium from caesium 137. The cases have been studied of small and medium-sized volumes, and of large volumes of about 100 litres. (authors) [fr

  2. The transition time induced narrow linewidth of the electromagnetically induced transparency in caesium vapour

    International Nuclear Information System (INIS)

    Li Luming; Peng Xiang; Liu Cheng; Guo Hong; Chen Xuzong

    2004-01-01

    We observed a narrow linewidth (∼60 kHz) in a Doppler-broadened system showing electromagnetically induced transparency in caesium atomic vapour. The transition time induced reduction of the linewidth is illustrated both theoretically and experimentally

  3. Development of prediction models for radioactive caesium distribution within the 80-km radius of the Fukushima Daiichi nuclear power plant

    International Nuclear Information System (INIS)

    Kinase, Sakae; Sato, Satoshi; Saito, Kimiaki; Takahashi, Tomoyuki; Sakamoto, Ryuichi

    2014-01-01

    Preliminary prediction models have been studied for the radioactive caesium distribution within the 80-km radius of the Fukushima Daiichi nuclear power plant. The models were represented by exponential functions using ecological half-life of radioactive caesium in the environment. The ecological half-lives were derived from the changes in ambient dose equivalent rates through vehicle-borne surveys. It was found that the ecological half-lives of radioactive caesium were not constant within the 80-km radius of the Fukushima Daiichi nuclear power plant. The ecological half-life of radioactive caesium in forest areas was found to be much larger than that in urban and water areas. (authors)

  4. Experience of iodine, caesium and noble gas release from AGR failures

    International Nuclear Information System (INIS)

    Chapman, C.J.; Harris, A.M.; Phillips, M.E.

    1985-01-01

    In the event of a fuel failure in an Advanced Gas Cooled Reactor (AGR), the quantity of fission products available for release to the environment is determined by the transport of fission products in the UO 2 fuel, by the possible retention of fission products in the fuel can interspace and by the deposition of fission products on gas circuit surfaces ('plate-out'). The fission products of principal radiological concern are radioactive caesium (Cs-137 and Cs-134) and iodine (principally I-131). Results are summarised of a number of experiments which were designed to study the release of these fission products from individual fuel failures in the prototype AGR at Windscale. Results are also presented of fission product release from failures in commercial AGRs. Comparisons of measured releases of caesium and iodine relative to the release of the noble gas fission products show that, for some fuel failures, there is a significant retention of caesium and iodine within the fuel can interspace. Under normal conditions circuit deposition reduces caesium and iodine gas concentrations by several orders of magnitude. Differing release behaviour of caesium and iodine from the failures is examined together with subsequent deposition within the sampling equipment. These observations are important factors which must be considered in developing an understanding of the mechanisms involved in circuit deposition. (author)

  5. Uptake and retention of radio-caesium in earthworms cultured in soil contaminated by the Fukushima nuclear power plant accident.

    Science.gov (United States)

    Fujiwara, K; Takahashi, T; Nguyen, P; Kubota, Y; Gamou, S; Sakurai, S; Takahashi, S

    2015-01-01

    To understand the effects of radionuclides on non-human biota and the environment, it is essential to study the intake and metabolism of radio-isotopes in earthworms which are among the most important soil organisms, and Eisenia fetida, which were used in this study, are known to be sufficiently sensitive to chemicals and representative of common earthworms. In this study, we assessed the concentration ratios, uptake and retention, absorbed dose rate, and distribution of radio-caesium in earthworms. The concentration ratios of (137)Cs (i.e., the concentrations of radio-caesium in earthworms relative to those in dry soil) were higher early in the culturing period and decreased gradually over the experimental period. (137)Cs taken up by E. fetida was cleared rapidly after the worms were cultured in radio-caesium-free soil, suggesting that the metabolism of radio-caesium in earthworms is very rapid. Autoradiography demonstrated that the concentration of radio-caesium within the digestive tract was as high as that in the soil, while radio-caesium in the body tissue was lower than radio-caesium in the soil and was almost uniformly distributed among earthworm tissues. The highest absorbed dose rate of total exposure to radio-caesium ((137)Cs + (134)Cs) was calculated to be 1.9 × 10(3) (μGy/day) in the earthworms. Copyright © 2014 Elsevier Ltd. All rights reserved.

  6. Caesium dynamics in the peats and associated vegetation of northern Greece and northern Scotland

    International Nuclear Information System (INIS)

    Heaton, B.; Mitchell, R.D.J.; Killham, K.; Veresoglou, D.S.

    1990-01-01

    Sequential analyses have shown that Chernobyl-derived caesium has been largely retained in Greek basin peats (highly cultivated, base-rich, sedge peats) and retained/cycled in Scottish upland peats (uncultivated, base-poor, blanket peats). To investigate the mechanisms of retention and cycling in the Scottish peat/vegetation system, a laboratory experiment was carried out involving 'microcosms' intact peat cores. Festuca ovina was grown from seed in the cores prior to nebuliser-application of simulated rain containing caesium-134. The major factors investigated were competitive ion exchange from ammonium (designed to simulate animal waste inputs), freeze-thaw activity, and cropping (designed to simulate upland grazing). The effects of these factors are discussed in relation to the physio-cochemical and biological properties of the peat and vegetation and to our observations of the movement of caesium in the field. (author)

  7. Clinical results in carcinoma of the cervix: radium compared to caesium using remote afterloading

    International Nuclear Information System (INIS)

    Jackson, S.M.; Fairey, R.N.; Kornelsen, R.O.; Young, M.E.J.; Wong, F.L.

    1989-01-01

    In 1979 the Cancer Control Agency of British Columbia changed from radium to remote controlled afterloaded caesium in the treatment of carcinoma of the cervix. In 3 years prior to the change, 139 patients received radium as part of their treatment and in the 3 years after the change, 158 patients received caesium. Overall referral patterns, patient and cancer demographics, and treatment policies were stable throughout the 6-year period. Radiotherapy technique, dose, dose distribution and dose rate were comparable for both radium and caesium treated patients. The results of treatment in the two time periods showed no difference in survival, local tumour control or complications. The use of afterloading has not compromised treatment results and has allowed better nursing care for patients and protection from radiation for all staff. (author)

  8. Radioactive caesium in a boreal forest ecosystem and internally absorbed dose to man

    International Nuclear Information System (INIS)

    Bergman, R.; Johansson, L.

    1989-01-01

    Different aspects dealing with water-soil, soil-plant and plant-herbivore interactions are studied. The study area is located to the Forest Research Station at Svartberget 50 km west of Umea in Vaesterbotten. An important topic in this study concerns the transport of caesium in food chains to man. Consumption of forest products by man i.e. game (primarily moose) and berries constitutes the major pathway of radioactive caesium to man. Moose meat contributes to about 30% of the total meat consumption in Vaesterbotten and the average over the Swedish population has remained at the level of 5-10% during the present decade. In order to assess the absorbed dose resulting from intake via these food products over a long period of time, knowledge about the long term behaviour of caesium in the biotic community is studied. (orig./HP)

  9. Mechanism of caesium ion exchange on potassium cobalt hexacyanoferrates(II)

    Energy Technology Data Exchange (ETDEWEB)

    Lehto, J.; Haukka, S.; Harjula, R. (Helsinki Univ. (Finland). Dept. of Radiochemistry); Blomberg, M. (Helsinki Univ. (Finland). Dept. of Physics)

    1990-03-01

    The caesium uptakes by K{sub 2}(CoFe(CN){sub 6}) and non-stoicheiometric compounds K{sub 2/x}Co{sub x/2}(CoFe(CN){sub 6}) were found to correlate directly with the specific surface areas of the products with x < 1. The exchange process is assumed to involve only the outermost surface layer of their crystals, which have cubic lattice, i.e. only potassium (or cobalt) ions inside the elementary cubes closest to the surface of the crystals are exchanged for caesium ions. Compounds with x > 1 are mixtures of cubic potassium cobalt hexacyanoferrate (ii) and tetragonal Co{sub 2}Fe(CN){sub 6}. The thermodynamic equilibrium constant of the caesium exchange on K{sub 2}(CoFe(CN){sub 6}) was found to have a high value of 125. (author).

  10. A survey of radioactive caesium in British soils

    International Nuclear Information System (INIS)

    Cawse, P.A.; Baker, S.J.

    1990-08-01

    The accumulation of radioactive caesium-137 in soils under permanent grassland was measured by Harwell Laboratory in 1977. The objective was to provide at selected locations in Great Britain a reference of background radioactivity in soil resulting from depositions of nuclear weapons fallout over some thirty years. Following the Chernobyl reactor accident in April 1986, the Department of the Environment requested further measurements at the reference sites in 1987 to record changes and regional differences in the amounts present in soil caused by radioactive fallout. Results from the 1987 survey generally showed the highest accumulations of Cs-137 derived from both nuclear weapons and Chernobyl fallout in western and northern regions of Great Britain, owing to the effectiveness of rainfall on scavenging of radioactivity from the atmosphere. Thus the reference sites in south-west and central Scotland had the maximum accumulation of 26kBq Cs-137/m 2 to 30cm soil depth, at Burrow Head and Rannoch; at these locations the soil concentrations attained 256Bq/kg whereas at all sites in England levels were 2 . To 30cm depth, an average soil concentration in Scotland of ∼ 100Bq/kg was derived, which is 11% of the generalised derived limit (GDL). Comparison of 1987 results with decay-corrected 1977 data showed that nine locations in England receiving negligible Chernobyl fallout had a net loss of Cs-137 by soil erosion and/or leaching over the ten-years interval. At other locations in England a minimum of 6-40% of Cs-137 to 30cm depth was Chernobyl-derived, but this increased to 50-95% in Scotland where substantial accumulations of Cs-134 were also recorded. At the two peat sites in north-east Scotland the accumulated deposition of Cs-137 in 1987 was two and five-fold greater than in 1977. In peatland vegetation the concentrations of Cs-137 followed the order sphagnum mosses > heather > g

  11. Bright triplet excitons in caesium lead halide perovskites

    Science.gov (United States)

    Becker, Michael A.; Vaxenburg, Roman; Nedelcu, Georgian; Sercel, Peter C.; Shabaev, Andrew; Mehl, Michael J.; Michopoulos, John G.; Lambrakos, Samuel G.; Bernstein, Noam; Lyons, John L.; Stöferle, Thilo; Mahrt, Rainer F.; Kovalenko, Maksym V.; Norris, David J.; Rainò, Gabriele; Efros, Alexander L.

    2018-01-01

    Nanostructured semiconductors emit light from electronic states known as excitons. For organic materials, Hund’s rules state that the lowest-energy exciton is a poorly emitting triplet state. For inorganic semiconductors, similar rules predict an analogue of this triplet state known as the ‘dark exciton’. Because dark excitons release photons slowly, hindering emission from inorganic nanostructures, materials that disobey these rules have been sought. However, despite considerable experimental and theoretical efforts, no inorganic semiconductors have been identified in which the lowest exciton is bright. Here we show that the lowest exciton in caesium lead halide perovskites (CsPbX3, with X = Cl, Br or I) involves a highly emissive triplet state. We first use an effective-mass model and group theory to demonstrate the possibility of such a state existing, which can occur when the strong spin-orbit coupling in the conduction band of a perovskite is combined with the Rashba effect. We then apply our model to CsPbX3 nanocrystals, and measure size- and composition-dependent fluorescence at the single-nanocrystal level. The bright triplet character of the lowest exciton explains the anomalous photon-emission rates of these materials, which emit about 20 and 1,000 times faster than any other semiconductor nanocrystal at room and cryogenic temperatures, respectively. The existence of this bright triplet exciton is further confirmed by analysis of the fine structure in low-temperature fluorescence spectra. For semiconductor nanocrystals, which are already used in lighting, lasers and displays, these excitons could lead to materials with brighter emission. More generally, our results provide criteria for identifying other semiconductors that exhibit bright excitons, with potential implications for optoelectronic devices.

  12. Uptake and retention of radio-caesium in earthworms cultured in soil contaminated by the Fukushima nuclear power plant accident

    International Nuclear Information System (INIS)

    Fujiwara, K.; Takahashi, T.; Nguyen, P.; Kubota, Y.; Gamou, S.; Sakurai, S.; Takahashi, S.

    2015-01-01

    To understand the effects of radionuclides on non-human biota and the environment, it is essential to study the intake and metabolism of radio-isotopes in earthworms which are among the most important soil organisms, and Eisenia fetida, which were used in this study, are known to be sufficiently sensitive to chemicals and representative of common earthworms. In this study, we assessed the concentration ratios, uptake and retention, absorbed dose rate, and distribution of radio-caesium in earthworms. The concentration ratios of 137 Cs (i.e., the concentrations of radio-caesium in earthworms relative to those in dry soil) were higher early in the culturing period and decreased gradually over the experimental period. 137 Cs taken up by E. fetida was cleared rapidly after the worms were cultured in radio-caesium-free soil, suggesting that the metabolism of radio-caesium in earthworms is very rapid. Autoradiography demonstrated that the concentration of radio-caesium within the digestive tract was as high as that in the soil, while radio-caesium in the body tissue was lower than radio-caesium in the soil and was almost uniformly distributed among earthworm tissues. The highest absorbed dose rate of total exposure to radio-caesium ( 137 Cs + 134 Cs) was calculated to be 1.9 × 10 3 (μGy/day) in the earthworms. - Highlights: • We assessed the concentration ratios of 137 Cs in earthworms/dry soil. • The distribution of radio-caesium was relatively uniform throughout the earthworm body without any distinguishable accumulation in specific organs or tissues. • We estimated the absorbed dose rate of radio-caesium for earthworms

  13. Investigations on caesium 134 and 137 contamination of game hunted for food in Hessia

    International Nuclear Information System (INIS)

    Hadlock, R.M.; Harju, H.; Sattler, E.L.; Wagner, G.

    1990-01-01

    The amount of caesium 134 and 137 in Hessian game hunted for food (556 animals) after the reactor accident at Chernobyl was investigated. Comparisons have been made before and after the accident. Although there was only a very low level of contamination, the contamination rate of different species varied; on average, the Red Deer showed the highest activity (130 Bq/kg). The level of caesium contamination was mostly influenced by the permanent habitat of the animals. The main influence was due to regional, geographical and meteorological conditions. The influence of age or sex could not be determined. The contamination rate was shown to decrease with time [de

  14. A Falls Dam, Otago, sedimentation rate measured by the caesium-137 profile

    International Nuclear Information System (INIS)

    McCabe, W.J.; Mason, W.J.

    1982-09-01

    Two cores from the dam were examined. The lead-210 was measured from Core D, but because of the high sedimentation rate the ''unsupported'' lead-210 was not detectable above the ''supported'' lead background. Caesium-137 was determined from Core A and the profile obtained related to the pattern of the ''fallout'' caesium in rainwater. From this a sedimentation rate of 11 kg per sq. metre per year was calculated. In terms of the length of the core sample, this is equivalent to 1.3 cm per year

  15. Mechanism of caesium ion exchange on potassium cobalt hexacyanoferrates(II)

    International Nuclear Information System (INIS)

    Lehto, J.; Haukka, S.; Harjula, R.; Blomberg, M.

    1990-01-01

    The caesium uptakes by K 2 [CoFe(CN) 6 ] and non-stoicheiometric compounds K 2/x Co x/2 [CoFe(CN) 6 ] were found to correlate directly with the specific surface areas of the products with x 1 are mixtures of cubic potassium cobalt hexacyanoferrate (ii) and tetragonal Co 2 Fe(CN) 6 . The thermodynamic equilibrium constant of the caesium exchange on K 2 [CoFe(CN) 6 ] was found to have a high value of 125. (author)

  16. Kinetics of caesium and potassium absorption by roots of three grass pastures and competitive effects of potassium on caesium uptake in Cynodon sp.

    Science.gov (United States)

    Ayub, J. Juri; Valverde, L. Rubio; Garcia-Sanchez, M. J.; Fernandez, J. A.; Velasco, R. H.

    2008-08-01

    Caesium uptake by plant roots has been normally associated with the uptake of potassium as the potassium transport systems present in plants have also the capacity to transport caesium. Three grass species (Eragrostis curvula, Cynodon sp and Distichlis spicata) growing in seminatural grassland of central Argentina were selected to study their capability to incorporate Cs+ (and K+) using electrophysiological techniques. Although the 137Cs soil inventory ranged between 328-730 Bq m-2 in this region, no 137Cs activity was detected in these plants. However, all the species, submitted previously to K+ starvation, showed the uptake of both Cs+ and K+ when micromolar concentrations of these cations were present in the medium. The uptake showed saturation kinetics for both cations that could be fitted to the Michelis-Menten model. KM values were smaller for K+ than for Cs+, indicating a higher affinity for the first cation. The presence of increasing K+ concentrations in the assay medium inhibited Cs+ uptake in Cynodon sp., as expected if both cations are transported by the same transport systems. This effect is due to the competition of both ions for the union sites of the high affinity potassium transporters. In field situation, where soil concentration of Cs+ is smaller than K+ concentration, is then expectable that caesium activity in plants is not detectable. Nevertheless, the studied plants would have the capacity to incorporate caesium if its availability in soil solution increases. In addition, studies of Cs/K interaction can help us to understand the variability in transfer factors.

  17. Kinetics of caesium and potassium absorption by roots of three grass pastures and competitive effects of potassium on caesium uptake in Cynodon sp

    International Nuclear Information System (INIS)

    Ayub, J. Juri; Velasco, R. H.; Valverde, L. Rubio; Garcia-Sanchez, M. J.; Fernandez, J. A.

    2008-01-01

    Caesium uptake by plant roots has been normally associated with the uptake of potassium as the potassium transport systems present in plants have also the capacity to transport caesium. Three grass species (Eragrostis curvula, Cynodon sp and Distichlis spicata) growing in seminatural grassland of central Argentina were selected to study their capability to incorporate Cs + (and K + ) using electrophysiological techniques. Although the 137 Cs soil inventory ranged between 328-730 Bq m -2 in this region, no 137 Cs activity was detected in these plants. However, all the species, submitted previously to K + starvation, showed the uptake of both Cs + and K + when micromolar concentrations of these cations were present in the medium. The uptake showed saturation kinetics for both cations that could be fitted to the Michelis-Menten model. K M values were smaller for K + than for Cs + , indicating a higher affinity for the first cation. The presence of increasing K + concentrations in the assay medium inhibited Cs + uptake in Cynodon sp., as expected if both cations are transported by the same transport systems. This effect is due to the competition of both ions for the union sites of the high affinity potassium transporters. In field situation, where soil concentration of Cs + is smaller than K + concentration, is then expectable that caesium activity in plants is not detectable. Nevertheless, the studied plants would have the capacity to incorporate caesium if its availability in soil solution increases. In addition, studies of Cs/K interaction can help us to understand the variability in transfer factors

  18. The selectivity of zirconium phosphate for caesium in electrochemical ion exchange

    International Nuclear Information System (INIS)

    Lain, M.J.

    1988-11-01

    The properties of amorphous zirconium phosphate are investigated as an inorganic ion exchanger for use in liquid waste treatment by electrochemical ion exchange. Experiments to determine and increase the selectivity for caesium exchange over sodium are discussed, including various pulsed waveforms and studies with rotating membranes. Automation of a sampling system with pH and atomic absorption measurements is described. (author)

  19. Swimming clusters in thallium-rich liquid caesium-thallium alloys

    NARCIS (Netherlands)

    van der Aart, SA; van der Lugt, W; Badyal, YS; Verkerk, P

    The purpose of the work presented here is to obtain structural information on thallium-rich caesium-thallium alloys by means of neutron diffraction. The alloys exhibit a long-range (>1 nm) superstructure. This range increases with the thallium content. The results are interpreted with the help of a

  20. Caesium inhibits the colonization of Medicago truncatula by arbuscular mycorrhizal fungi

    International Nuclear Information System (INIS)

    Wiesel, Lea; Dubchak, Sergiy; Turnau, Katarzyna; Broadley, Martin R.; White, Philip J.

    2015-01-01

    Contamination of soils with radioisotopes of caesium (Cs) is of concern because of their emissions of harmful β and γ radiation. Radiocaesium enters the food chain through vegetation and the intake of Cs can affect the health of organisms. Arbuscular mycorrhizal (AM) fungi form mutualistic symbioses with plants through colonization of the roots and previous studies on the influence of AM on Cs concentrations in plants have given inconsistent results. These studies did not investigate the influence of Cs on AM fungi and it is therefore not known if Cs has a direct effect on AM colonization. Here, we investigated whether Cs influences AM colonization and if this effect impacts on the influence of Rhizophagus intraradices on Cs accumulation by Medicago truncatula. M. truncatula was grown with or without R. intraradices in pots containing different concentrations of Cs. Here, we present the first evidence that colonization of plants by AM fungi can be negatively affected by increasing Cs concentrations in the soil. Mycorrhizal colonization had little effect on root or shoot Cs concentrations. In conclusion, the colonization by AM fungi is impaired by high Cs concentrations and this direct effect of soil Cs on AM colonization might explain the inconsistent results reported in literature that have shown increased, decreased or unaffected Cs concentrations in AM plants. - Highlights: • Colonization of plants by arbuscular mycorrhizal fungi is negatively affected by increasing soil caesium concentrations. • Shoot caesium concentrations are not influenced by AM fungi at soil caesium concentrations above about 3 μg Cs kg −1 . • The direct effect of caesium on AM fungi might impact on the influence of AM fungi on Cs accumulation in plants. • This might explain the inconsistent results reported in literature on Cs accumulation in AM plants

  1. The accumulation of radioactive caesium from water by the brown trout (Salmo trutta) and its comparison with plaice and rays

    International Nuclear Information System (INIS)

    Hewett, C.J.; Jefferies, D.F.

    1976-01-01

    The patterns of accumulation of caesium-137 from water by the tissues and organs of the freshwater teleost, the brown trout (Salmo trutta) are described. Estimates of the biological half-times and steady-state concentrations are derived, using a simple exponential equation. In all tissues and organs examined, other than muscle, the rate processes of the trout fall between those of the plaice and the ray. It is concluded that most of the caesium accumulated by the brown trout from water enters other than by the gut, probably through the gills, but as with plaice and ray, the main source of the caesium, possibly 90%, must come from the food. Despite differences in the levels of accumulation, the ratios of the tissue to blood steady state concentrations were very similar in all three species. The steady state caesium concentration of the blood appeared to be directly related to the red blood cell count of the fish. (author)

  2. Availability of caesium radionuclides to plants - classification of soils and role of mycorrhiza

    Energy Technology Data Exchange (ETDEWEB)

    Drissner, J.; Buermann, W.; Enslin, F.; Heider, R.; Klemt, E.; Miller, R.; Schick, G.; Zibold, G. [Fachhochschule Ravensburg-Weingarten, D-88241 Weingarten (Germany)

    1998-10-01

    At different locations in spruce stands spread rather homogeneously over southern Baden-Wuerttemberg, samples of soil and plants were taken and the vertical distribution of the caesium radionuclides in the soil was studied. As a direct measure of the bioavailability, the aggregated transfer factor, T{sub ag}, was determined for fern, bilberry, raspberry, blackberry, and clover. The T{sub ag} (in m2 kg{sup -1}) is defined by the specific caesium activity (in Bq kg{sup -1}) of the dry mass of the plants, divided by the total inventory (in Bq m{sup -2}) of the soil. It varies between 0{center_dot}5 and 0{center_dot}001 m2kg{sup -1}, being highest for fern and lowest for blackberry or clover at all sampling sites. Most decisive for the value of the T{sub ag} are kind of humus deposit, thickness and pH value of the humus layers. Also important are the soil properties, whereas geology has only a minor influence on T{sub ag}. At different sampling sites in spruce forests, the T{sub ag} can vary by two orders of magnitude for one plant species. Caesium desorption experiments were performed. We could not find a dependence of the transfer of caesium to the plant on the desorbability of caesium from the soil, which implies a more complex transport mechanism than simple ion exchange in the soil solution. It is suggested that the transport of caesium is mediated by mycorrhiza fungi. Therefore, we studied the density of mycorrhiza hyphae in the O{sub f}, O{sub h} and A{sub h} soil horizons of two sites differing in T{sub ag} by a factor of 10. The densities of mycorrhiza hyphae in the O{sub h} and A{sub h} soil horizons each differ by a factor of 2 for the two sites. Yet, the effect of the hyphae density on radiocaesium uptake has to be a subject of further investigation. (Copyright (c) 1998 Elsevier Science B.V., Amsterdam. All rights reserved.)

  3. Deposition of caesium and strontium substances on growing crops: Effects and countermeasures

    International Nuclear Information System (INIS)

    Bengtsson, S.

    2010-01-01

    Full text: To investigate how the two radionuclides caesium ( 134 Cs) and strontium ( 85 Sr) are taken up and transported to the harvested parts (the seeds) by fallout in a growing crop. Further on how this is related to the size and time of the fallout. From the information collected recommendation of suitable countermeasures at different scenarios to prevent further spreading to food stuff can be suggested. In the project a number of field trials where artificial deposited by the two radionuclides 134 Cs and 85 Sr in a contaminated rainfall, on the two agricultural crops Brassica napus L. (spring rape) and Triticum aestivum L. (spring wheat). The trial contained different treatments where the radionuclides where deposited by a rainfall simulator at different growing stages of the crops. The field trial continues for two more years and the reason for that is due to the variation of the climate for the different years. The radionuclides were applied in the form of a wet deposition and the rainfall was about 1 mm m -1 with a concentration of 20 kBq m -1 for each radionuclide. Samples were taken from the plots at the day(s) after the treatment of contaminated rainfall, both from the latest treated plots and from the earlier treated plots. The hypotheses are: 1. That the size of the deposition and the time in relation to the development stages of the crop will steer how much caesium and strontium that are coughed, detained and transferred to the harvested parts. 2. That the levels of caesium and strontium in the harvested parts of the crops are related to the insensitivity of the rainfall after a deposition and also how long time the first intensive rain will occur. 3. That the size of caesium and strontium in harvested plant parts are related to the size of uptake throw the leaves. 4. If the deposition of caesium and strontium will be the same, the levels of caesium will be much higher than strontium in the harvested parts. (author)

  4. Caesium extraction from acidic high level liquid wastes with functionalized calixarenes

    International Nuclear Information System (INIS)

    Simon, N.; Eymard, S.; Tournois, B.; Dozol, J.F.

    2000-01-01

    In the framework of French law programme, studies are under way to selectively remove caesium from acidic high activity wastes. Calix[4]arene crown derivatives exhibit outstanding efficiency and selectivity for caesium. An optimisation of the formulation of a selective extractant system for Cs based on crown calixarenes and usable in a process which use liquid-liquid extraction is presented. A system involving a monoamide as a modifier is proposed. Besides these improvements, a reference solvent based on a standard 1,3-di-(n-octyl-oxy)2,4-calix(4)arene crown is studied. Flow-sheets related to this system are calculated and easily transferable to the optimised new system. (authors)

  5. Measurement of metabolism of worker ants by using the elimination of caesium-134

    International Nuclear Information System (INIS)

    Nielsen, M.G.; Jensen, T.F.

    1977-01-01

    In order to find a method for measuring field metabolism of worker ants the elimination of 134 Cs by two ant species has been investigated. Equations relating temperature to radiocaesium elimination and metabolism have been found. From these equations the relationship between elimination and metabolism is calculated. Consequently, the elimination of the isotope can be used for measuring metabolism. A pilot field experiment with Lasius alienus (Foerst.) reveals that the traditional methods of estimating field metabolism give values which are considerably lower than the value based on caesium elimination rate. This difference is supposed to be mainly due to greater motor activity of the animals in the field. Consequently, the value of the caesium elimination method is closer to the 'true' value of field metabolism. (orig.) [de

  6. New ion selective materials. Application to the selective extraction of caesium

    International Nuclear Information System (INIS)

    Favre-Reguillon, Alain

    1996-01-01

    This research thesis addresses the synthesis and assessment of ion selective materials. The first part reports the development of a general method of assessment of ion selective materials. In the second part, the author describes different methods used to insolubilize macro-cycles on hydrophilic polymers. The obtained polyurethanes are synthesised. These hydrophilic polymers display interesting complexing properties and selectivities with respect to cations of alkali metals. Then the author addresses the improvement of selectivity with respect to caesium of ion exchange resorcinol-formaldehyde resins. Different factors affecting selectivity are identified, and the concept of molecular print is used to study the improvement of selectivity. The effect of macro-cyclic structures on phenolic resins with respect to caesium is highlighted [fr

  7. Caesium-137 as an indicator of geomorphic processes in a drainage basin system

    International Nuclear Information System (INIS)

    Campbell, B.L.; Elliott, G.L.

    1982-01-01

    Caesium-137 from fallout from nuclear weapons tests is adsorbed on fine sediments and becomes an effective tracer. It is hypothesised that within a drainage basin, sites undergoing little or no erosion accumulate Cs-137 in their upper layers; cultivated soils will have Cs-137 uniformly distributed within the cultivated layer; eroded soils, cultivated or not, will have relatively less Cs-137, depending on the severity of erosion. Accumulated sediments will have characteristic Cs-137 profiles reflecting temporal fallout variations and sedimentation history. This hypothetical model is largely confirmed by results from Maluna Creek basin, where erosion and accumulation of sediments has taken place. Soils under viticulture have about one third the Cs-137 content of soils with grass cover, indicating more severe erosion under cultivation. Caesium-137 profiles in alluvial fan and flood plain deposits correlate with sediment layers and known cultivation history

  8. Polarization and pressure effects in caesium 6S-8S two-photon spectroscopy

    International Nuclear Information System (INIS)

    Lee, Yi-Chi; Tsai, Chin-Chun; Chui, Hsiang-Chen; Chang, Yi-Hsiu; Chen, Ying-Yu

    2010-01-01

    This work analyses the effects of polarization and pressure in caesium 6S-8S two-photon spectroscopy. The linewidth was broadened and the frequency was shifted by a change of polarization states. The frequency shift and the linewidth broadening of the caesium 6S-8S two-photon transition were measured as a function of laser power using one single-frequency Ti:sapphire ring cavity laser, two caesium cells and two quarter-wave plates to ensure polarization states of light, and we showed that the linewidth cannot be evaluated just by fitting data to a Lorentzian shape. As determined by fitting the data to a Voigt profile, the natural linewidth is independent of the polarization states of the pump beams, the laser power and the pressure. Caesium 6S-8S two-photon transitions pumped by a circularly polarized beam have narrower linewidths and smaller shifts than those pumped by a linearly polarized beam. The light shift obtained by pumping with the circularly polarized beam is -6.75(57) Hz (mW mm -2 ) -1 , and that obtained by pumping with a linearly polarized beam is -7.25(45) Hz (mW mm -2 ) -1 . These results agree closely with theoretical calculations. The pressure shift is -588(387) Hz mPa -1 . This work shows how to evaluate two-photon transitions with a Voigt profile, and then helps us to understand two-photon transitions with different polarization states, and improve the signal quality obtained when they are used as frequency markers.

  9. Caesium-137 in a boreal forest ecosystem. Aspects on the long-term behaviour

    International Nuclear Information System (INIS)

    Bergman, R.; Nylen, T.; Nelin, P.; Palo, T.

    1993-11-01

    Cycling of radioactive caesium, particularly the isotope Cs-137, is studied in boreal forest biotopes mainly located at the Vindeln experimental forest, 60 km NW of Umeaa, Sweden, (64 degrees 16'N, 19 degrees 48'E). The distribution of radioactive caesium in this forest ecosystem, prior to and in different periods after the Chernobyl accident, reflects the existence of fast changes particularly at an early stage after the deposition, superimposed on slow redistribution over long time periods. The definite causes to this complex dynamic behaviour are not yet unambiguously established. In this work we use the specific results from local field studies as a basis to describe the general pattern and time dependence of Cs-137 redistribution in a boreal forest. We raise the hypothesis that: 'Cs-137 present in a boreal forest tends towards a homogenous distribution among the living cells of that system'. This hypothesis is based on physiological characteristics concerning transport over cell membranes and intracellular distribution in comparison to potassium, and the apparently conservative conditions prevailing for caesium in boreal ecosystems - e.g. the facts that very little of the radioactive caesium deposited over the forest area is lost from the system by run off, more than 90% of the total deposition of Cs-137 resides in the upper organic horizon in podzol areas, and that the availability in the ecosystem, as can be seen from the Cs-137 concentration in moose meat, is not significantly different in 1985 (i.e. prior to the Chernobyl accident) in comparison to the period 1986-1990. The aim of this work is to elucidate how predictions, based on our hypothesis about redistribution processes in the boreal forest, corroborates with the main features in the time-dependent change of Cs-137 activity, according to measurements on perennial vegetation from the local sites. In particular the implicit dependence of the dynamics of the redistribution processes on primary

  10. Psychosocial aspects of the victims of the accident with caesium-137 in Goiania (1987-1994)

    Energy Technology Data Exchange (ETDEWEB)

    Curado, M P [Fundacao Leide das Neves Ferreira, Goias (Brazil); Costa Neto, S B [Universidade de Brasilia, Instituto de Psicologia, Rio de Janeiro (Brazil)

    2000-05-01

    In September of 1987 two men took possession of and violated a source containing Caesium-137, which caused the Radiological Accident of Goiania. Besides the direct victims, a significant part of the community of Goiania was directly involved with this accident. The psychosocial impact in the social groups involved in this radiological accident - the population as a whole, immediate neighbours of contaminated sites, professionals and the victims themselves - gave rise to specific behaviour and attitudes which will be discussed in this paper. (author)

  11. Surface conductivity of the single crystal aluminum oxide in vacuum and caesium vapors

    International Nuclear Information System (INIS)

    Vasilchenko, A.V.; Izhvanov, O.L.

    1996-01-01

    Results of measurements of surface conductivity of single-crystal aluminum oxide samples in vacuum and cesium vapors at T=620 endash 830 K and P Cs =0.13 endash 2 Pa are shown in the paper. Analysis of caesium vapor influence is carried out and ultimate characteristics of samples conductivity under operation conditions in thermionic nuclear power system (NPP) TFE are estimated. copyright 1996 American Institute of Physics

  12. Psychosocial aspects of the victims of the accident with caesium-137 in Goiania (1987-1994)

    International Nuclear Information System (INIS)

    Curado, M.P.; Costa Neto, S.B.

    2000-01-01

    In September of 1987 two men took possession of and violated a source containing Caesium-137, which caused the Radiological Accident of Goiania. Besides the direct victims, a significant part of the community of Goiania was directly involved with this accident. The psychosocial impact in the social groups involved in this radiological accident - the population as a whole, immediate neighbours of contaminated sites, professionals and the victims themselves - gave rise to specific behaviour and attitudes which will be discussed in this paper. (author)

  13. Effects of cooking process on the changes of concentration and total amount of radioactive caesium in beef, wild plants and fruits

    International Nuclear Information System (INIS)

    Nabeshi, Hiromi; Tsutsumi, Tomoaki; Uekusa, Yoshinori; Matsuda, Rieko; Akiyama, Hiroshi; Teshima, Reiko; Hachisuka, Akiko

    2016-01-01

    In order to obtain information about effects of the cooking process on the changes of concentration and amount of radioactive materials in foods, we determined the concentration of radioactive caesium in several foods such as beef, edible wild plants, blueberries and mushrooms, before and after cooking. Our results showed that drying after soaking in liquid seasoning and the removal of astringent taste were effective in removing radioactive caesium from foods. More than 80% of radioactive caesium could be removed by these cooking methods. These results suggest that cooking processes such as boiling and soaking in liquid seasoning or water are effective to remove radioactive caesium from foods. Moreover, appropriate food additives such as baking soda were useful to promote the removal of radioactive caesium from foods. On the other hand, simple drying, jam making, grilling and tempura cooking could not remove radioactive caesium from foods. In addition, we showed that the concentration of radioactive caesium in foods was raised after simple drying, although the amount of radioactive caesium was unchanged. It would be necessary to monitor radioactive caesium concentration in processed foods because they might have undergone dehydration by cooking, which could result in concentrations exceeding regulatory levels. (author)

  14. Transfer of radioactive caesium from soil to vegetation and comparison with potassium in upland grasslands

    International Nuclear Information System (INIS)

    Coughtrey, P.J.; Kirton, J.A.; Mitchell, N.G.; Morris, C.

    1989-01-01

    The distribution and transfer of caesium and potassium between soils and vegetation has been investigated by field sampling and experimental studies on soils and vegetation typical of upland grassland in north west England. Total 137 Cs content to a depth of 0.05 m below root matt ranged from 13 000 to 18 000 Bq m -2 . This caesium content derives from three sources: the Windscale accident of 1957, weapons-testing fallout which peaked in the early 1960s, and the Chernobyl accident in May 1986. From 2200 to 6200 Bq m -2 is attributed to the first two sources, and the remainder to Chernobyl. During accelerated growth of vegetation, on monoliths in glasshouse conditions over the winter of 1986/87, 137 Cs was transferred from soil and root matt to new growth, such that concentrations in fresh growth were similar to or higher than those observed in the field during December 1986. Removal of caesium by successive cuts resulted in up to 25% of the original estimated total being removed over a 240 day period. Increased concentrations coincided with the emergence of Carex sp. and Trichophorum caespitosum, as well

  15. Decreasing of transfer of caesium and strontium radionuclides from soil to vegetation - Use of modified aluminosilicates for decreasing of transfer of caesium and strontium radionuclides from soil to vegetation

    Energy Technology Data Exchange (ETDEWEB)

    Voronina, Anna V.; Blinova, Marina O.; Semenischev, Vladimir S.; Kutergin, Andrey S. [Ural federal university, 620002 Ekaterinburg (Russian Federation)

    2014-07-01

    The method of addition of sorbents to soils is seemed to be the most efficient for decreasing of transfer of radionuclides from soil to vegetation. Using sorbents should possess affinity to natural systems, high specificity and selectivity and also irreversibility of sorption of radionuclides for effective retention of radionuclides as well as to prevent their migration into vegetation and further movement through food chains. Specificity, selectivity and reversibility of sorption of caesium and strontium radionuclides by natural aluminosilicates (glauconite, clinoptilolite) and modified ferrocyanide sorbents based on them was studied in this work. It was shown that the natural glauconite sorbs caesium from tap water with distribution coefficient K{sub d} = 10{sup (3.5±0.1)} mL/g, static exchange capacity of Cs is 11.0 mg/g; it shows lower specificity to strontium: K{sub d} = 10(2.5±0.1) mL/g, static exchange capacity = 9 mg/g. For clinoptilolite these parameters are for caesium K{sub d} = 10(4.4±0.5) mL/g, static exchange capacity 210 mg/g; for strontium K{sub d} = 10(3.5±0.1) mL/g, capacity = 12 mg/g. Ferrocyanide sorbents concentrate caesium radionuclides more effectively: distribution coefficient of Cs from tap water by mixed nickel-potassium ferrocyanide based on glauconite is 10(5.9±1.6) mL/g, static exchange capacity of Cs is (63.0±2.0) mg/g; for mixed nickel-potassium ferrocyanide based on clinoptilolite these characteristics are respectively 10(7.4±1.3) mL/g, 500 mg/g. In case of modified sorbents specificity to strontium remains the same as for natural aluminosilicates. Reversibility of sorption of caesium by natural glauconite and ferrocyanide sorbent was determined as caesium leaching degree from saturated samples. High caesium leaching rates and degrees are typical for natural glauconite irrespective of leachant salinity: total degree of leaching after 35 days of leaching was: mineral water = 63.4%, tap water = 41.6% and rain water = 28.8%. For

  16. A preliminary assessment of the potential for using caesium-137 to estimate rates of soil erosion in the Loess Plateau of China

    International Nuclear Information System (INIS)

    Zhang Xinbao

    1990-01-01

    The potential for using the radionuclide caesium-137 as an environmental tracer to indicate sources of soil erosion in the Chinese Loess Plateau is introduced. The caesium-137 contents of soil profiles have been used to estimate soil erosion losses from different topographic and land use conditions at Lishi, Shanxi Province, and Luochuan, Shaanxi Province. At uncultivated sites the caesium-137 has accumulated in the upper soil profile, whilst it has been mixed within the plough layer of cultivated soils. Eroded soils contain relatively less caesium-137, and simple calibration techniques are applied to quantify soil loss. Preliminary results suggest that caesium-137 may be of considerable value in assembling data on the rates and spatial distribution of soil loss and in identifying the source areas of eroded sediment. (author)

  17. Caesium 137: Properties and biological effects resulting of an internal contamination

    International Nuclear Information System (INIS)

    Lestaevel, P.; Racine, R.; Bensoussan, H.; Rouas, C.; Gueguen, Y.; Dublineau, I.; Bertho, J.M.; Gourmelon, P.; Jourdain, J.R.; Souidi, M.

    2010-01-01

    Caesium-137 ( 137 Cs) is a radionuclide present in the environment mainly as the result of the atmospheric nuclear weapons testing and accidents arising in nuclear power plants like the Chernobyl accident in 1986. Nowadays, the health consequences resulting from a chronic exposure to this radionuclide remain unknown. After absorption, the caesium is distributed relatively homogeneously within the body, with a more important load in children than in adults. The toxicity of 137 Cs is mainly due to its radiological properties. A high dose of 137 Cs is responsible for a medullar dystrophy, disorders of the reproductive function, and effects on liver and renal functions. Disorders of bone mineralization and brain damages were also described in human beings. At lowest dose, 137 Cs induces disturbances of wakefulness-sleep cycle, but not accompanied with behavioural disorders. The cardiovascular system was also perturbed. Biological effects of 137 Cs on the metabolisms of the vitamin D, cholesterol and steroid hormones were described, but do not lead to clinical symptoms. In human beings, 137 Cs leads to an immune deficiency, congenital and foetal deformations, an increased of thyroid cancer, as well as neurological disorders. It seems that children are more sensitive to the toxic effects of caesium than the adults. At present, the only effective treatment for the decorporation of the ingested 137 Cs is the Prussian Blue (Radiogardase). The use of pectin to de-corporate the ingested 137 Cs, in children notably, is sometimes proposed, but its administration still remains an open question. To conclude, the available scientific data suggest that 137 Cs could affect a number of physiological and metabolic functions and consequently, could participate in the health risks associated to the presence of other contaminants in the environment. (authors)

  18. Doses and risk estimates to the human conceptus due to internal prenatal exposure to radioactive caesium

    International Nuclear Information System (INIS)

    Kalef-Ezra, J.A.

    1997-01-01

    The 1986 nuclear reactor accident at Chernobyl resulted in widespread internal contamination by radioactive caesium. The aim of the present study was to estimate the doses to embryos/fetus in Greece attributed to maternal 134 Cs and 137 Cs intake and the consequent health risks to their offspring. In pregnant women the concentration of total-body caesium (TBCs) was lower than in age-matched non-pregnant women measured during the same month. A detailed study of intake and retention in the members of one family carried out during the three years that followed the accident indicated that the biological half-time of caesium in the women decreased by a factor of two shortly after conception. Then at partus, there was an increase in the biological half-time, reaching a value similar to that before conception. The total-body potassium concentration was constant over the entire period. Doses to the embryo/fetus due to maternal intake was estimated to be about 150 μGy maximally in those conceived between November 1986 and March 1987. When conception took place later, the prenatal dose followed an exponential reduction with a half-time of about 170 d. These prenatal doses do not exceed the doses from either the natural internal potassium, or from the usual external background sources. The risks attributed to maternal 134 Cs and 137 Cs intake were considerably lower than levels that would justify consideration of termination of a pregnancy. In the absence of these data however, 2500 otherwise wanted pregnancies in Greece were terminated following the Chernobyl accident. (author)

  19. Sorption of caesium and strontium onto calcium silicate hydrate in saline groundwater

    International Nuclear Information System (INIS)

    Sugiyama, D.; Fujita, T.

    2005-01-01

    Full text of publication follows: In the concept for radioactive waste disposal in Japan, cement is a potential waste packaging and backfilling material and is expected to provide chemical containment. The sorption of radionuclides onto cement materials, which controls the aqueous concentrations of elements in the pore-water, is a very important parameter when considering the release of radionuclides from the near field of a cementitious radioactive waste repository. Many safety assessment calculations currently assume radionuclide retardation as linear sorption equilibrium and describe it with a distribution ratio (R d value). In this study, the sorption mechanism is discussed by measuring the sorption isotherm of caesium, strontium (10 -5 ∼ 10 -2 mol dm -3 ) and sodium (10 -4 ∼ 10 -1 mol dm -3 ) onto Calcium Silicate Hydrate (C-S-H gel, Ca/Si 0.65 ∼ 1.2) at a liquid:solid ratio of 100:1, to support the assumption. In addition, the competitive sorption between caesium or strontium, and sodium is studied by sorption measurements using a range of sodium chloride concentration to simulate different ionic strengths in saline groundwater. The initial and equilibrated aqueous compositions were measured in the sorption experiments and it was found that caesium, strontium and sodium were sorbed by substitution for Ca in C-S-H phases by examining the mass balance. Based on the experimental results, we propose a modelling approach in which the ion-exchange model is employed and the presence of some calcium sites with different ion-exchange log K values in C-S-H is assumed by considering the composition and the structure of C-S-H. The modelling calculation results predict the measured Rd values well and also describe the competition of sorption of caesium or strontium, and sodium in the experiments. The log K values for sorption of each cation element decreased as Ca/Si ratio of C-S-H gel increased. This agrees with the trend that C-S-H gel is negatively charged at low

  20. The desorption of caesium from Peach Bottom HTGR steam generator materials

    International Nuclear Information System (INIS)

    Clark, M.J.

    1979-03-01

    The work at Harwell on the Peach Bottom End-of-Life Program in co-operation with the General Atomic Company (U.S.A.) is described. Materials taken from the Economiser, Evaporator and Superheater Sections of the Peach Bottom Unit No. 1. High Temperature Gas Cooled Reactor (HTGR) Heat Exchanger were placed in a reducing atmosphere comparable to the composition of an HTGR helium coolant gas, and the desorption of caesium isotopes measured under known conditions of flow, temperature and oxygen pressure. (author)

  1. Plasma-screening effects upon energy levels and electron scattering from neutral and ionized caesium

    International Nuclear Information System (INIS)

    Chin, Y.J.; Radtke, R.; Zimmermann, R.

    1988-01-01

    Using interaction potentials screened with the Debye-Hueckel length, the effects of plasma shielding on energy levels and electrons scattering from neutral and ionized caesium are estimated. Both energy levels and atomic scattering cross-sections are found to be sensitive to the inclusion of screening. Relating to the scattering by the Cs + ion, a low-energy resonance near E = 0.3 Ryd is found which arises from the f-wave phase shift and reflects the individual behaviour of the scattering ion. (author)

  2. Plasma-screening effects upon energy levels and electron scattering from neutral and ionized caesium

    Energy Technology Data Exchange (ETDEWEB)

    Chin, Y J; Radtke, R; Zimmermann, R

    1988-01-01

    Using interaction potentials screened with the Debye-Hueckel length, the effects of plasma shielding on energy levels and electrons scattering from neutral and ionized caesium are estimated. Both energy levels and atomic scattering cross-sections are found to be sensitive to the inclusion of screening. Relating to the scattering by the Cs/sup +/ ion, a low-energy resonance near E = 0.3 Ryd is found which arises from the f-wave phase shift and reflects the individual behaviour of the scattering ion.

  3. Alteration in caesium behavior in rice caused by the potassium, phosphorous, and nitrogen deficiency

    International Nuclear Information System (INIS)

    Tatsuya Nobori; Kobayashi, N.I.; Keitaro Tanoi; Nakanishi, T.M.

    2016-01-01

    The physiological effects of critical nutrient deficiencies (K, P, N) on the uptake of caesium (Cs) and impact on plant growth has been investigated in rice plants. Growth defects were observed after 2 weeks of a state of nutrient starvation (K, P, or N). However, only K starvation produced increased Cs content in the shoot and the intensive transport to young leaves. These observations support that modification of Cs uptake and transport in rice plants was achieved based on the distinctive physiological effect of K. (author)

  4. Patients blood serum ferritin concentrations changes associated with Caesium-137 incorporation

    International Nuclear Information System (INIS)

    Shishkyina, V.V.; Chebotar'ova, E.D.; Zamyatyin, S.S.; Vlasenko, O.O.

    1993-01-01

    The results of radioimmune study of ferritin and carcinoembryonic antigen in 60 persons: 35 those who took part in liquidation of the Chernobyl accident and incorporated 25.9-70.4 MBq of Cesium-137,25 residents of Rivno Region with 7.4-203.5 MBq of the radionuclide in the organism are reported. The increased concentration of ferritin and carcinoembryonic antigen in blood serum was noted to be determined more often in the residents of the areas polluted with Caesium-137 than in l iquidators . The tumor markers levels depended to some extent on bad habits (smoking, alcohol) and existing chronic diseases of the alimentary system

  5. Distribution coefficients of caesium, chlorine, iodine, niobium, selenium and technetium on Olkiluoto soils

    International Nuclear Information System (INIS)

    Soederlund, M.; Lusa, M.; Virtanen, S.; Vaelimaa, I.; Hakanen, M.; Lehto, J.; Lahdenperae, A.-M.

    2014-02-01

    Retention of caesium, chlorine, iodine, niobium, selenium and technetium was investigated on soil samples from Olkiluoto using laboratory batch sorption experiments. Distribution coefficients were measured for both dried and sieved and untreated (wet, not sieved) mineral soil and humus in aerobic and anaerobic conditions. Mineralogical composition of the samples was determined by XRD-analysis. Caesium was sorbed efficiently on mineral soil samples and less efficiently on humus. Sorption decreased with decreasing cation exchange capacity and clay fraction content. The effect of competing cations decreased in the order Cs + >NH 4 + >K + >Ca 2+ >Na + . Chlorine was not retained by mineral soil samples, and the sorption was weak on humus. The sorption of iodine was the strongest on humus and the weakest on the untreated mineral soil samples in the anaerobic conditions. In the mineral soil samples, the sorption decreased with decreasing organic matter content and increasing pH. The retention of niobium on soil samples was the most efficient among the studied elements. The retention was high regardless of the aeration conditions. Sorption on humus was smaller. Selenium was retained efficiently on humus. Sorption on mineral soil samples was stronger in aerobic conditions. Sorption increased with time. Technetium was sorbed well on humus and anaerobic, untreated mineral soil samples. Sorption increased with increasing organic matter content and decreasing redox potential. The results from the sorption experiments are used in the site specific radionuclide migration modelling. (orig.)

  6. Nuclear dynamics in the metastable phase of the solid acid caesium hydrogen sulfate.

    Science.gov (United States)

    Krzystyniak, Maciej; Drużbicki, Kacper; Fernandez-Alonso, Felix

    2015-12-14

    High-resolution spectroscopic measurements using thermal and epithermal neutrons and first-principles calculations within the framework of density-functional theory are used to investigate the nuclear dynamics of light and heavy species in the metastable phase of caesium hydrogen sulfate. Within the generalised-gradient approximation, extensive calculations show that both 'standard' and 'hard' formulations of the Perdew-Burke-Ernzerhof functional supplemented by Tkatchenko-Scheffler dispersion corrections provide an excellent description of the known structure, underlying vibrational density of states, and nuclear momentum distributions measured at 10 and 300 K. Encouraged by the agreement between experiment and computational predictions, we provide a quantitative appraisal of the quantum contributions to nuclear motions in this solid acid. From this analysis, we find that only the heavier caesium atoms reach the classical limit at room temperature. Contrary to naïve expectation, sulfur exhibits a more pronounced quantum character relative to classical predictions than the lighter oxygen atom. We interpret this hitherto unexplored nuclear quantum effect as arising from the tighter binding environment of this species in this technologically relevant material.

  7. Factors influencing caesium-137 levels in moose (Alces alces) and small game in Northern Sweden

    International Nuclear Information System (INIS)

    Nelin, P.; Palo, T.R.

    1989-01-01

    In the third annual hunting season after the Chernobyl accident the concentration of Cs-137 in meat of northern Swedish moose was significantly higher than in the first one (1986). In September 1986 the mean Cs concentration was 500 Bq/kg in calves but in September 1988 it has risen 1300 Bq/kg. This increase was only temporary and a rapid decline occured after September and by December 1988 the concentration of Cs was the same as in late 1986. Adult moose showed the same increase during the hunt 1988 but to a lower magnitude. Typical food plants of moose such as bilberry (Vaccinum myrtillus) and birch (Betula pubescens) showed, contradictory to expected by the level in moose, a decline of concentration caesium from 1986 to 1988. A probable explanation to the dramatically increased concentration of Cs in moose is a change in diet selection during 1988. Small mammals such as voles and lemmings showed a variation in concentration of caesium-137 which was more dependent on other factors than on their body size. This emphasize the necessity to study diet selection by herbivores in detail in order to predict uptake and changes in environmental contaminants. (orig.)

  8. Sources of present Chernobyl-derived caesium concentrations in surface air and deposition samples

    Energy Technology Data Exchange (ETDEWEB)

    Hoetzl, H.; Rosner, G.; Winkler, R. (Gesellschaft fuer Strahlen-und Umweltforschung Munich, Neuherberg (Germany). Forschungszentrum fuer Umwelt und Gesundheit Gesellschaft fuer Strahlen- und Umweltforschung mbH Muenchen, Neuherberg (Germany). Inst. fuer Strahlenschutz)

    1992-06-01

    The sources of Chernobyl-derived caesium concentrations in air and deposition samples collected from mid-1986 to end-1990 at Munich- Neuherberg, Germany, were investigated. Local resuspension has been found to be the main source. By comparison with deposition data from other locations it is estimated that within a range from 20 Bq m[sup -2] to 60 kBq m[sup -2] of initially deposited [sup 137]Cs activity [approx]2% is re-deposited by the process of local resuspension in Austria, Germany, Japan and United Kingdom, while significantly higher total resuspension is to be expected for Denmark and Finland. Stratospheric contribution to present concentrations is shown to be negligible. This is confirmed by cross correlation analysis between the time series of [sup 137]Cs in air and precipitation before and after the Chernobyl accident and the respective time series of cosmogenic [sup 7]Be, which is an indicator of stratospheric input. Seasonal variations of caesium concentrations with maxima in winter were observed. (author). 32 refs.; 5 figs.; 1 tab.

  9. Sources of present Chernobyl-derived caesium concentrations in surface air and deposition samples

    International Nuclear Information System (INIS)

    Hoetzl, H.; Rosner, G.; Winkler, R.; Gesellschaft fuer Strahlen- und Umweltforschung mbH Muenchen, Neuherberg

    1992-01-01

    The sources of Chernobyl-derived caesium concentrations in air and deposition samples collected from mid-1986 to end-1990 at Munich- Neuherberg, Germany, were investigated. Local resuspension has been found to be the main source. By comparison with deposition data from other locations it is estimated that within a range from 20 Bq m -2 to 60 kBq m -2 of initially deposited 137 Cs activity ∼2% is re-deposited by the process of local resuspension in Austria, Germany, Japan and United Kingdom, while significantly higher total resuspension is to be expected for Denmark and Finland. Stratospheric contribution to present concentrations is shown to be negligible. This is confirmed by cross correlation analysis between the time series of 137 Cs in air and precipitation before and after the Chernobyl accident and the respective time series of cosmogenic 7 Be, which is an indicator of stratospheric input. Seasonal variations of caesium concentrations with maxima in winter were observed. (author). 32 refs.; 5 figs.; 1 tab

  10. NPL's contribution to the introduction of the caesium second

    Energy Technology Data Exchange (ETDEWEB)

    Whibberley, Peter [National Physical Laboratory, Teddington (United Kingdom). Time and Frequency Group

    2017-09-15

    For centuries timekeeping was the preserve of astronomers. The fundamental unit of time measurement was the day, sub-divided by clocks for everyday use into hours, minutes and seconds. By the early 20th century, clocks were sufficiently stable to indicate that the length of the mean solar day varied, though their lack of intrinsic accuracy (the rate of a clock depended on its mechanical properties) ensured that the Earth's rotation remained the global reference standard for timekeeping. This situation changed fundamentally in June 1955, when Louis Essen and Jack Parry brought the first caesium atomic clock into operation at the National Physical Laboratory, in Teddington, UK. The atomic clock not only provided a much more stable timekeeper than the Earth's rotation; its reference was the frequency of an atomic transition - a fundamental constant of nature, determined by the laws of quantum mechanics. As a result all caesium clocks will run at essentially the same rate, limited only by noise processes and their local environment, regardless of time or place.

  11. Adsorption of Caesium in Urine on Copper Hexacyanoferrate(II) - A Contamination Control Kit for Large-Scale In-Situ Use

    International Nuclear Information System (INIS)

    Johansson, L.; Samuelsson, C.; Holm, E.

    1999-01-01

    A kit containing copper hexacyanoferrate(II) was created for large scale distribution to caesium-contaminated subjects for in situ sampling in the event of radiocaesium release from a nuclear accident of other nuclear activities. This kit is to be used for screening the internal contamination level of a population exposed to radiocaesium fallout and could be seen as a fast method of whole-body counting, suitable for large scale determinations. The separation of caesium from urine by adsorption on the copper compound was studied and it was determined that caesium efficiently adsorbed from urine. The contamination control kit is a practical alternative to urine sampling since caesium is concentrated to a small volume, by the subject using the kit in situ, gaining advantages in handling, distribution, storage and measuring geometry in the subsequent gamma ray analysis. The kit consists of cotton filters impregnated with copper hexacyanoferrate(II) held by plastic filter holders and performs a rapid flow-through. In order to obtain full caesium adsorption, less than 0.5 g of the compound is required for a 2 litre urine sample. No chemical preparation or change in pH of the urine sample is needed before adsorption. When using the kit in an authentic internal caesium contamination situation, the adsorbed fraction of caesium was 97 ± 3% (SD) in ten samples. (author)

  12. Photoluminescence properties of Er-doped Ge–In(Ga)–S glasses modified by caesium halides

    Czech Academy of Sciences Publication Activity Database

    Ivanova, Z.G.; Zavadil, Jiří; Kostka, P.; Djouama, T.; Reinfelde, M.

    2017-01-01

    Roč. 254, č. 6 (2017), č. článku 1600662. ISSN 0370-1972 Institutional support: RVO:67985882 Keywords : caesium halides * chalcohalide glasses * erbium doping * transmission spectroscopy * photoluminiscence Subject RIV: JH - Ceramics, Fire-Resistant Materials and Glass OBOR OECD: Ceramics Impact factor: 1.674, year: 2016

  13. Photoluminescence properties of Er-doped Ge–In(Ga)–S glasses modified by caesium halides

    Czech Academy of Sciences Publication Activity Database

    Ivanova, Z.G.; Zavadil, Jiří; Kostka, Petr; Djouama, T.; Reinfelde, M.

    2017-01-01

    Roč. 254, č. 6 (2017), č. článku 1600662. ISSN 0370-1972 Institutional support: RVO:67985891 Keywords : caesium halides * chalcohalide glasses * erbium doping * transmission spectroscopy * photoluminiscence Subject RIV: JH - Ceramics, Fire-Resistant Materials and Glass OBOR OECD: Ceramics Impact factor: 1.674, year: 2016

  14. Determination of caesium in river and sea waters by electrothermal atomic-absorption spectrometry. Interference of cobalt and iron

    International Nuclear Information System (INIS)

    Frigieri, P.; Trucco, R.; Ciaccolini, I.; Pampurini, G.

    1980-01-01

    For the enrichment or the simple recovery of caesium from river and sea waters, selective inorganic exchangers were considered. Ammonium hexacyanocobalt ferrate (NCFC) was chosen because it can be used in strongly acidic solutions (with the exception of concentrated sulphuric acid). Caesium is fully retained by the NCFC chromatographic column and can then be recovered by dissolution in hot sulphuric acid. The solution is then diluted and analysed, either directly or following caesium separation, by atomic-absorption spectrometry. To check the reliability of the analytical procedure, a series of experiments were carried out in which the possible interfering species were added to the aqueous caesium solution prior to analysis. The well known ionic interference in flame atomisation processes caused by magnesium, calcium, strontium and metals was investigated by electrothermal atomisation measurements. The experimental data showed that this effect does not occur even when these elements are present in concentrations of the order of thousands of parts per million. However, strong interferences from iron and cobalt were observed. (author)

  15. Use of caesium-137 as a tracer of erosion and sedimentation: Handbook for the application of the caesium-137 technique. UK Overseas Development Administration research scheme R4579

    Energy Technology Data Exchange (ETDEWEB)

    Walling, D E; Quine, T A

    1993-10-01

    The caesium 137 technique has become an important tool for investigating soil erosion. It permits retrospective assessment of medium-term erosion rates. The application of the technique requires only one field visit, and the results can be provided within a relatively short time. The soil redistribution rates estimated represent an average for the last 30-35 years, and are therefore less influenced by extreme events. The rates estimated represent the sum of all erosive processes. Both rates and patterns of soil redistribution may be quantitatively assessed. A range of erosion estimates may be obtained, including mean rates of erosion and deposition and net rates of soil export from the field. The whole field may be studied without disturbance to the slope environment. The spatial resolution of the data obtained is defined by the sampling strategy. Chapters of part 1 discuss the basis of the {sup 137}Cs technique, the potential for its further development, and define a protocol for its application. Part 2 includes descriptions of case studies from China, Zimbabwe and Lesotho, which illustrate the value of the {sup 137}Cs technique in the assessment of soil erosion.

  16. Use of caesium-137 as a tracer of erosion and sedimentation: Handbook for the application of the caesium-137 technique. UK Overseas Development Administration research scheme R4579

    International Nuclear Information System (INIS)

    Walling, D.E.; Quine, T.A.

    1993-10-01

    The caesium 137 technique has become an important tool for investigating soil erosion. It permits retrospective assessment of medium-term erosion rates. The application of the technique requires only one field visit, and the results can be provided within a relatively short time. The soil redistribution rates estimated represent an average for the last 30-35 years, and are therefore less influenced by extreme events. The rates estimated represent the sum of all erosive processes. Both rates and patterns of soil redistribution may be quantitatively assessed. A range of erosion estimates may be obtained, including mean rates of erosion and deposition and net rates of soil export from the field. The whole field may be studied without disturbance to the slope environment. The spatial resolution of the data obtained is defined by the sampling strategy. Chapters of part 1 discuss the basis of the 137 Cs technique, the potential for its further development, and define a protocol for its application. Part 2 includes descriptions of case studies from China, Zimbabwe and Lesotho, which illustrate the value of the 137 Cs technique in the assessment of soil erosion

  17. Study of caesium contamination in foodstuffs in Ghana after the Chernobyl nuclear accident

    International Nuclear Information System (INIS)

    Darko, E.O.; Schandorf, C.; Yeboah, J.

    1996-01-01

    Fallout radioactivity has been studied in foodstuffs in the Environmental Monitoring Laboratory after the Chernobyl nuclear catastrophe. The study covers the analysis of reference samples of imported foods, mainly meat and milk, for 137 Cs and 134 Cs contamination using a low-level gamma spectrometer. The purpose of this study is to determine whether it is necessary to control food imports in order to reduce the risk from intake of radionuclides by the Ghanian public resulting from transboundary contamination. Measurement of caesium levels in various foods over a period of seven years has shown contamination to be within the recommended action levels for international trade in foods. The committed effective dose intakes in any single year is far below the 1 mSv annual dose recommended by the ICRP in Publication 60. (author)

  18. Sedimentation of cobalt-60 and caesium-137 released in Tvaeren, a Baltic bay

    International Nuclear Information System (INIS)

    Ramberg, L.

    1984-01-01

    The amounts of cobalt-60 and caesium-137 bound in the sediment in a bay off the Studsvik research station were determined. Of the cumulative released activity during 22 years, 19% of 60 Co and 1.8% of 137 Cs were found in the sediments within an area of 23 km 2 . The rate of input through sedimentation and the loss rate through physical decay were of the same order in 1981 and were close to steady state for 60 Co while for 137 Cs they had only reached 30% of that level. The sedimentation coefficients calculated for the bay were 6.5 year -1 for 60 Co and 0.49 year -1 for 137 Cs, higher values than many published previously. Cobalt-60 seemed to precipitate close to the outlet and to migrate near the bottom as bed-load. (author)

  19. Production of intensive negative lithium beam with caesium sputter-type ion source

    Science.gov (United States)

    Lobanov, Nikolai R.

    2018-01-01

    Compounds of lithium oxide, hydroxide and carbonate, mixed with silver, were prepared for use as a cathode in caesium-sputter ion source. The intention was to determine the procedure which would produce the highest intensity negative lithium beams over extended period and with maximum stability. The chemical composition and properties of the samples were analysed using mass-spectrometry, optical microscopy, Scanning Electron Microscopy (SEM), Energy Dispersive X-ray Analyses (EDX) and Raman spectroscopy. These analyses showed that the chemical transformations with components resulted from pressing, storage and bake out were qualitatively in agreement with expectations. Intensive negative lithium ion beams >1 μA were delivered using cathodes fabricated from materials with multicomponent chemical composition when the following conditions were met: (i) use of components with moderate enthalpy of formation; (ii) low moisture content at final stage of cathode production and (iii) small concentration of water molecules in hydrate phase in the cathode mixture.

  20. Caesium-137 in Saamis and reindeer in Kautokeino, Norway, 1965-1999

    International Nuclear Information System (INIS)

    Skuterud, L.; Mehli, H.; Floe, L.

    1999-01-01

    In the early 1960ies, during the period of the atmospheric nuclear weapons testing, it was realised that people consuming reindeer meat contained higher concentrations of radioactive caesium (i.e. 137 Cs) than the rest of the population of Northern areas. This is because reindeer graze significant amounts of lichen during winter, and lichen absorb and accumulate nutrients and contaminants directly from air and precipitation. In 1965, as a response to this knowledge, Norwegian authorities started a monitoring programme among reindeer herding Saamis in Kautokeino (60 deg. N, 23 deg. E), a 0687 km 2 municipality of Finnmark county where reindeer herding is an important way of living. The aim of the programme was to assess internal doses to the group of the Norwegian population that was assumed to be subject to the highest exposures from 137 Cs from the nuclear testing in general, and the testing at the Soviet test site at Novaya Zamlya in particular. (au)

  1. Caesium Radionuclide Uptake from Wet Soil to Kangkung Plant (Ipomoea sp)

    International Nuclear Information System (INIS)

    Putu Sukmabuana; Poppy Intan Tjahaja

    2009-01-01

    Caesium radionuclide transfer from soil to kangkung plant (Ipomoea sp) generally consumed by people had been examined to obtain transfer factor value for internal radiation dose assessment via soil-plant-human pathway. The kangkung plants were cultivated on watered soil medium containing 134 Cs with concentration of about 80 Bq/g, and the 134 Cs uptake by plants, i.e root, stem, and leaves, were measured using gamma spectrometer. The 134 Cs plant uptake was expressed as transfer factor, i.e. ratio of plant 134 Cs concentration to 134 Cs concentration on soil medium. From this research it was obtained transfer factor value of 134 C from soil to plant is 0.07, and the transfer factor for root, stem, and leaves are 0.34 ; 0.05 ; 0,03 respectively, after 45 days cultivation. The transfer factor values are less than one, indicate that kangkung plant do not accumulate Cs radionuclide from soil. (author)

  2. Redistribution of caesium-137 by erosion and deposition on an australian soil

    International Nuclear Information System (INIS)

    McCallan, M.E.; Rose, C.W.; O'Leary, B.M.

    1980-01-01

    Caesium-137, a nuclear fallout product which is carried down to the ground by rainfall and becomes tightly adsorbed to soil particles, is being used to study soil erosion and accumulation. The measurement of 137 Cs activity in soil cores in an upland catchment on the Darling Downs has revealed a vertical and areal distribution of this isotope which is in general agreement with expectations based on the topography, the observed erosion and deposition sites, the variation in 137 Cs fallout through time, and hypotheses of 137 Cs redistribution. Such information may allow the development of a practical technique for estimating soil erosion and accumulation rates using this isotope; it also allows testing of mathematical models of erosion/deposition processes

  3. Monitoring of caesium-137 in food plants and muscle from moose, red deer and wild reindeer in 2010

    International Nuclear Information System (INIS)

    Veiberg, Vebjoern; Gaare, Eldar; Stokke, Sigbjoern; Solberg, Erling J.; Skuterud, Lavrans

    2011-01-01

    The monitoring of Cs-137 fall-out from the Chernobyl accident in 1986, started the same year. Several plants and wild reindeer in natural ecosystems in Nord-Rondane have been followed annually ever since. Four more wild reindeer ranges were included in 2001: Setesdal-Ryfylkeheiene, Hardangervidda, Nord-Ottadalen, Snoehetta and Nord-Rondane. From 2007 Forollhogna was also included. On fixed plots in Nord-Rondane and Snoehetta some of the reindeer forage plants, including both higher plants and fruticose lichens, have been sampled and analyzed annually since 1986. This was also done in 2010. In addition plants and lichens were sampled at five locations along an altitudinal gradient at Soendre Knutshoe, and at 7-8 locations along an east-west gradient from Kollaflata to Skarhoe in the Jora valley continuing along the Aursjoe to Torbudalen. All these locations were sampled annually between 1987-1990, but they have not been sampled since. In 2010 samples from red deer and moose was also collected from eight different regions located within the following counties: Oppland, Telemark, Vest-Agder, Rogaland, Sogn and Fjordane, Nord-Troendelag, Nordland and Troms. Red deer were sampled in four regions and moose in six. Both species were sampled in Oppland. In 2010 76, 49 and 61 samples were collected from wild reindeer, red deer and moose respectively. All measures of caesium levels were performed on dried samples. For the 596 samples of plants and lichen the results refer to caesium-levels in dried samples. For the meat samples, results refer to caesium-137 levels in raw meat. Due to large variation in measured levels of caesium within species and sampling area, we give median values instead of mean values.The highest caesium levels in wild reindeer were found in Snoehetta (1010 Bq/kg) and Nord-Rondane (2686 Bq/kg). The levels found in the other areas were considerably lower. The highest caesium levels in both red deer (Sel, 677 Bq/kg) and moose (Vaaga, 365 Bq/kg) were found

  4. Estimation of committed effective dose from radioactive caesium contained in kindergarten supply of food during one year after Fukushima Daiichi Nuclear Power Plant accident

    International Nuclear Information System (INIS)

    Midorikawa, Miho; Hayashi, Toru

    2013-01-01

    For the purpose of contributing to an understanding about the situation of radioactive contamination of kindergarten lunch, contents of radioactive caesium and 40 K in lunch supplied by the attached kindergarten of Seitoku University was calculated by using the data on radioactive contamination of foodstuffs published by the Japanese Government. The average value of daily intake of radioactive caesium was estimated at lower than 1Bq and that of 40 K was 8.6Bq. Total amount of radioactive caesium in the lunch for one year was about 100Bq and that of 40 K was 1100Bq, resulting in a committed effective dose from radioactive caesium at about 1μSv. (author)

  5. Caesium-137 distribution, inventories and accumulation history in the Baltic Sea sediments.

    Science.gov (United States)

    Zaborska, Agata; Winogradow, Aleksandra; Pempkowiak, Janusz

    2014-01-01

    The Baltic Sea is susceptible to pollution by hazardous substances due to limited water exchange, shallowness, and the large catchment area. Radionuclides, particularly (137)Cs, are one of the most hazardous anthropogenic substances present in the Baltic environment. This study was conducted to present (137)Cs present contamination that should further be a subject of reliable monitoring when the new Nuclear Power Plant is put into operation in the northern Poland. The sea-wide, up to date distribution of (137)Cs activities and inventories in the Baltic Sea bottom sediments are presented. The (137)Cs activity concentrations were measured in 30 cm long sediment cores collected at 22 sampling stations. Sediment accumulation rates were quantified by (210)Pb geochronology to follow the history of (137)Cs accumulation. The (137)Cs inventories and fluxes were calculated. Most of the Baltic Sea sediments accumulated (137)Cs in the range from 750 to 2675 Bq m(-2). The Bothnian Bay is severely contaminated by (137)Cs with inventories up to 95,191 Bq m(-2). This region is moreover characterized by extremely large patchiness of (137)Cs inventories. The (137)Cs annual fluxes are highest at the two stations located at the Bothnian Bay (342 Bq m(-2) and 527 Bq m(-2)) due to large Chernobyl (137)Cs contamination of that region and high sediment accumulation rates. When these stations are excluded, the recent, annual mean value of (137)Cs load to the Baltic Sea deposits is 38 ± 22 Bq m(-2). The distribution of radio-caesium inventories over the Baltic Sea nowadays reflects the pattern of Chernobyl contamination. The radio-caesium deposited in surface sediments is not permanently buried, but may be resuspended and redeposited by currents, bioturbation or anthropogenic activities. Copyright © 2013 Elsevier Ltd. All rights reserved.

  6. Caesium concentration factors in wild herbivores and the fox (Vulpes vulpes L.)

    International Nuclear Information System (INIS)

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

    1991-01-01

    A selection of wild animals was sampled in the winter of 1986/87. The sites chosen for sampling were based on information obtained from surveys carried out by The Institute of Terrestrial Ecology in the spring and autumn of 1986. Animals included deer, grouse, hares and rabbits, and foxes which were collected as a top carnivore in the food chain. Variation in concentration of caesium between species from the same area was unpredictable; rabbits never exceeded 200 Bq kg -1 (fresh wt) of 137 Cs in their flesh, even when adjacent to deer forests with over 1000 Bq kg -1 in the venison. The greatest complication arose from areas of peaty uplands where the pre-Chernobyl 137 Cs from weapons-testing was much higher than expected. This pre-Chernobyl contribution amounted to 630 Bq kg -1 in a red grouse from the Pennines, and 650 Bq kg -1 in a roe deer from near the Borders, being c. 60% of the total. Significant differences in concentration factors were found depending on species, food, sex, breeding condition and age. Contrasting the decrease of the two caesium isotopes in roe deer from forestry on peat with those from woodlands on mineral soils, it appeared that after an initial fall in concentration, the only decrease thereafter occurred on the mineral soils. Nowhere were radiocaesium concentrations high enough to cause concern amongst consumers of game and other wild animals, even when levels exceed 3000 Bq kg -1 (fresh wt) as they did in red deer, red grouse and the blue hare. (author)

  7. Caesium accumulation by microorganisms: uptake mechanisms, cation competition, compartmentalization and toxicity

    International Nuclear Information System (INIS)

    Avery, S.V.

    1995-01-01

    The continued release of caesium radioisotopes into the environment has led to a resurgence of interest in microbe-Cs interactions. Caesium exists almost exclusively as the monovalent cation Cs + in the natural environment. Although Cs + is a weak Lewis acid that exhibits a low tendency to form complexes with ligands, its chemical similarity to the biologically essential alkali cation K + facilitates high levels of metabolism-dependent intracellular accumulation. Microbial Cs + (K + ) uptake is generally mediated by monovalent cation transport systems located on the plasma membrane. These differ widely in specificity for alkali cations and consequently microorganisms display large differences in their ability to accumulate Cs + ; Cs + appears to have an equal or greater affinity than K + for transport in certain microorganisms. Microbial Cs + accumulation is markedly influenced by the presence of external cations, e.g. K + , Na + , NH 4 + and H + , and is generally accompanied by an approximate stoichiometric exchange for intracellular K + . However, stimulation of growth of K + -starved microbial cultures by Cs + is limited and it has been proposed that it is not the presence of Cs + in cells that is growth inhibitory but rather the resulting loss of K + . Increased microbial tolerance to Cs + may result from sequestration of Cs + in vacuoles or changes in the activity and/or specificity of transport systems mediating Cs + uptake. The precise intracellular target(s) for Cs + - induced toxicity has yet to be clearly defined, although certain internal structures, e.g. ribosomes, become unstable in the presence of Cs + and Cs + is known to substitute poorly for K + in the activation of many K + -requiring enzymes. (author)

  8. The CNEN Helium-Caesium Blow-Down MPD Facility and Experiments with a Prototype Duct

    Energy Technology Data Exchange (ETDEWEB)

    Bertolini, E.; Toschi, R. [CNEN, Frascati (Italy); Lindley, B. C. [C.A. Parsons and Co. Ltd (United Kingdom); Brown, R.; McNab, I. R. [International Research and Development Co. Ltd., Newcastle Upon Tyne (United Kingdom)

    1966-11-15

    The CNEN blow-down loop has been designed to study a helium-caesium MPD generator with particular regard to non-equilibrium ionization effects. An operating condition of the loop is: gas mass flow 0.2 kg/sec, seed fraction 1 at, wt.%, useful pulse duration 20 sec, stagnation temperature 2000 Degree-Sign K, stagnation pressure 5 atm abs, thermal power 1.6 MW, Mach number 0.6, magnetic field 4 Wb/m2, total impurity level less than 100 ppm. A sufficiently wide range of the stagnation conditions can be obtained with the present arrangement of the loop (temperature up to 2000*K, pressure from slightly sub-atmospheric to 6atmabs, gas mass flow from 50 g/sec to 400 g/sec, seed fraction from 0.1 to 2 at. wt.%. The storage heater is an alumina pebble bed electrically heated with tungsten elements and thermally insulated with zirconia fibre; the thermal capacity at 2000 Degree-Sign K is about 1000 MJ. Pure helium is obtained by evaporation of liquid helium at between 4.5 and 5 Degree-Sign K; liquid caesium is injected into a limited section of the pebble bed to provide a mixture of the two gases uniform in density and temperature. The duct is made of boron nitride (5 cm x 3 cm x 22 cm) with 25 pairs of tantalum electrodes whose geometry (electrode width 3 mm, segmentation pitch 9 mm) should prevent current leakage between adjacent electrodes; the duct walls and transfer can be pre-heated up to 1700 Degree-Sign K. A magnetic field of 4 Wb/m{sup 2} is obtained with a pulsed cryogenic magnet with pulse duration of 6 sec. Two series of experiments have been completed to assess the feasibility of the helium-caesium heating system and the generator duct. Heating system experiments, (a) Compatibility of alumina with tungsten, tantalum and caesium, with thermal cycling at 2000 Degree-Sign K; (b) Purification of zirconia fibre and its behaviour at high temperature, with thermal cycling at 2000 Degree-Sign K; (c) Capability of an alumina pebble bed of evaporating, heating and mixing

  9. Crystal structure of caesium hydrogen (L)-aspartate and an overview of crystalline compounds of aspartic acid with inorganic constituents

    Energy Technology Data Exchange (ETDEWEB)

    Fleck, M. [Universitaet Wien (Austria). Institut fuer Mineralogie und Kristallographie; Emmerich, R.; Bohaty, L. [Universitaet zu Koeln (Austria). Institut fuer Kristallographie

    2010-08-15

    The crystal structure of the new polar compound caesium hydrogen (L)-aspartate, Cs(C{sub 4}H{sub 6}NO{sub 4}), (abbreviated: Cs(L -AspH)) was determined from single crystal X-ray diffraction data; it comprises two crystallographically different L -AspH anions that are connected via caesium cations to form a three dimensional framework. The Cs ions are irregularly sevenfold[Cs1O{sub 7}] respectively eightfold[Cs2O{sub 8}] coordinated to all {alpha}- and {beta}- carboxylate oxygen atoms. Cs(L -AspH) represents a novel structure type of its own, as do most compounds of (L)-aspartic acid with inorganic constituents. A brief summary of such structurally known aspartates is given. (copyright 2010 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  10. Radioactive caesium in Boreal forest landscapes - Dynamics and transport in food webs. Summary of research 1986-1996

    International Nuclear Information System (INIS)

    Bergman, R.; Nylen, T.; Palo, T.

    1998-12-01

    The need for - but also the paucity of - radioecological knowledge concerning the boreal forest became particularly apparent after the nuclear power plant accident in Chernobyl in April 1986. As a consequence several new projects were initiated in the Nordic countries with particular focus on the behaviour of radioactive caesium in terrestrial and aquatic systems characteristic for the Fenno-Scandinavian landscapes. Among these new projects a multi-disciplinary co-operation in Umeaa between scientists at the Swedish University of Agricultural Sciences, and the Defence Research Establishment emerged. Initially this joint work focused mainly on descriptions of the dynamic changes of the content of radioactive caesium in soil-plant and animal communities in the county of Vaesterbotten. Most of the studies have been performed at the Vindeln experimental forest, 60 km NW of Umeaa. Plants of key interest were: bilberry (Vaccinium myrtillus), birch (Betula spp.), and pine (Pinus sylvestris), and among the animals: the moose (Alces alces) and a small rodent, the forest vole (Clethrionomus glareolus). Gradually over the past ten years the research has entered the stage where the specific causes of the caesium behaviour have been addressed - partly by the help of models developed for simulating forest ecosystems, partly by complementary field experiments. This paper reviews our main findings on this theme concerning the behaviour of radioactive caesium in boreal landscapes and significant pathways to man, as has become apparent from the radioecological co-operation dating from about ten years back. A list of the publications arising from these studies since 1986 is also presented in this report

  11. Long-term loss rates of radioisotopes of cobalt, zinc, ruthenium, caesium and silver by Mytilus edulis under field conditions

    International Nuclear Information System (INIS)

    Dahlgaard, H.

    1999-01-01

    Long-term loss rates of cobalt, zinc, ruthenium, caesium and silver by Mytilus edulis soft parts as well as shells were measured under field conditions in the Mediterranean Sea at Monaco during a period of 13 months after experimental contamination. For all 5 elements, the loss could be described by two exponential functions for the soft parts and one for the shells. Biological half lives for the long-lived compartment ranged from ∼20 days for caesium to 100 - 200 days for cobalt, zinc, ruthenium and silver for soft parts as well as for shells. A comparison with results from similar experiments performed under very different environmental conditions in the Baltic Sea indicated that caesium and maybe silver had a faster turnover in the warm and saline Mediterranean, whereas loss rates for cobalt and zinc were comparable. It is argued, that reliable deduction of loss rates require experiments running over several months to a year, and it is pointed out that shorter term experiments - even up to 3 months - may give biased results. (author)

  12. Caesium-137 distribution, inventories and accumulation history in the Baltic Sea sediments

    International Nuclear Information System (INIS)

    Zaborska, Agata; Winogradow, Aleksandra; Pempkowiak, Janusz

    2014-01-01

    The Baltic Sea is susceptible to pollution by hazardous substances due to limited water exchange, shallowness, and the large catchment area. Radionuclides, particularly 137 Cs, are one of the most hazardous anthropogenic substances present in the Baltic environment. This study was conducted to present 137 Cs present contamination that should further be a subject of reliable monitoring when the new Nuclear Power Plant is put into operation in the northern Poland. The sea-wide, up to date distribution of 137 Cs activities and inventories in the Baltic Sea bottom sediments are presented. The 137 Cs activity concentrations were measured in 30 cm long sediment cores collected at 22 sampling stations. Sediment accumulation rates were quantified by 210 Pb geochronology to follow the history of 137 Cs accumulation. The 137 Cs inventories and fluxes were calculated. Most of the Baltic Sea sediments accumulated 137 Cs in the range from 750 to 2675 Bq m −2 . The Bothnian Bay is severely contaminated by 137 Cs with inventories up to 95,191 Bq m −2 . This region is moreover characterized by extremely large patchiness of 137 Cs inventories. The 137 Cs annual fluxes are highest at the two stations located at the Bothnian Bay (342 Bq m −2 and 527 Bq m −2 ) due to large Chernobyl 137 Cs contamination of that region and high sediment accumulation rates. When these stations are excluded, the recent, annual mean value of 137 Cs load to the Baltic Sea deposits is 38 ± 22 Bq m −2 . The distribution of radio-caesium inventories over the Baltic Sea nowadays reflects the pattern of Chernobyl contamination. The radio-caesium deposited in surface sediments is not permanently buried, but may be resuspended and redeposited by currents, bioturbation or anthropogenic activities. -- Highlights: • 137 Cs contamination in the Baltic Sea was studied before the new NPP is put into operation. • Bothnian Sea sediments are severely contaminated by 137 Cs (inventories up to 95,191 Bq m

  13. The use of the environmental Caesium-137 for soil erosion study at Kalumpang Agriculture Station

    International Nuclear Information System (INIS)

    Othman, Zainudin

    2004-01-01

    Rapid industrial development and intensive agriculture land use induce soil erosion, increase surface runoff and subsequent deposition of eroded sediment. It is a serious threat to sustainable agricultural development and environmental conservation. Several methods have been developed to assess the degree of soil erosion. One of the method currently being applied is using environmental isotope caesium-137. Caesium-137 (1 37C s) is a product of nuclear weapons tests during the 1950s to 1970s. Fallout of 137 Cs from the atmosphere is distributed globally and become part of the world ecosystem. The fallout has been used as an indicator of soil erosion and sediment deposition status. Since it has been uniformly deposited on the soil, the sites with no net soil loss should have 137 Cs inventories that reflect the amount of 137 Cs fallout, less the loss due to radioactive decay, 137 Cs has a half-life 30 years. The level of 137 Cs at an undisturbed site provides a reference value for assessing the degree of erosion and deposition within the area. The sites having concentration less than the reference value can be considered eroded and the sites having more than the reference value can be regarded as depositional (Walling and Quine, 1992). In recent years, there has been an increase increasing attention of using this technique it offers as an alternative technique in providing more information and answers to some soil erosion and sediment deposition status. In order to establish the spatial variability of 137 Cs in the soil in the erosion plot, soil samples were collected using a motorized corer at 72 sampling points in a sloping erosion plot of an area 120 x 50 meter. In this study, a slope transects technique was employed because the site was characterised by a simple topography. Four combine soil cores are needed at each point for analysis. The results strongly indicated that 137 Cs concentration was uniformly distributed throughout the cultivation layer of the plot

  14. Mapping of caesium fallout from the Chernobyl accident in the Jotunheimen area

    International Nuclear Information System (INIS)

    Baranwal, Vikas C.; Ofstad, Frode; Roenning, Jan S.; Watson, Robin J.

    2011-01-01

    As a consequence of the Chernobyl accident, several areas in Norway received radioactive fallout. One of these areas is the eastern part of Jotunheimen in central Norway. Immediately after the accident in 1986, the Geological Survey of Norway (NGU) performed airborne gamma-ray spectroscopy in central Norway. At that time, it was not possible to calculate reliable radionuclide concentrations, and the data were presented as total counts per second. Several man-made radionuclides were present in the initial fallout, but due to short half-lives, most of these have now disintegrated into stable isotopes. 137Cs, with a half-life of 11.000 days (∼ 30 years) is still present in the environment in significant quantities, leading to high radioactivity levels in meat from reindeer and sheep. To obtain a detailed map of the caesium fallout concentration in Jotunheimen, an airborne gamma-ray spectrometry (AGRS) survey was carried out, focusing on reindeer grazing areas. This project was a cooperation between Reindeer Husbandry Administration, Norwegian Radiation Protection Authority and the Geological Survey of Norway.(Au)

  15. On the biological half-life of caesium in pregnant women and infants

    International Nuclear Information System (INIS)

    Rundo, J.; Turner, F.M.

    1992-01-01

    In the 1960s, changes were observed in the levels of 137 Cs in women who were pregnant or who had recently given birth. These were not associated with changes in the rate of fall-out, and were interpreted as the consequences of changes in the biological half-life. It was deduced that the biological half-life of caesium just before parturition averaged 59% of the value (87±33 days) after the birth of the baby; and that there was a step change at parturition. The behaviour of the levels during pregnancy suggested there was a gradual decrease in the biological half-life. Similar measurements were made in very young children. The concentration of the radionuclide in a breast-fed baby was usually a little less than that in the mother, indicating some discrimination in the transfer from plasma to milk; the concentration in a bottle-fed baby increased substantially and rapidly from the level at or shortly after birth. Data for three babies were sufficiently extensive to permit determination of the biological half-life in each. Values of 8.7±0.6 days, 15.4±1.1 days, and 14.9±3.6 days were derived. (author)

  16. Estimation of Caesium-137 Intake in Dicentrarchus Labrax by Using Compartmental Model and Neural Network

    International Nuclear Information System (INIS)

    Yahaghi, E.; Movafeghi, A.; Askari, M. A.; Karimi Diba, G.; Mohammadzadeh, N.

    2012-01-01

    Cs-137 is one of the fission products that is usually released in environment after nuclear accidents. This contamination remains in environment for a long time due to long half life of Cs-137 (30 years) and can enter easily into the human food chain. A two-compartmental model was implemented to describe caesium intake and its distribution in Dicentrarchus Labrax, using a proposed differential equation model. The model included two compartments, the first compartment was the blood and the second one was the tissue. The activity of Cs-137 was undertaken in each compartment by means of a numerical method and the activity of Cs-137 was considered as an input of compartmental equations. We obtained the transfer coefficients between fish tissues by comparing the radiation curves with the actual data. In the light of the differences with the transfer coefficients, the calculation by the COMKAT software was found to be about 2%. Then, we provided the activity curves of Cs-137 and their characteristics (feature extractions) by changing the transfer coefficients and they were utilized to train the neural network. The network was trained for six data groups, and the results of the network testing had about 99% correct response, therefore it can be employed to estimate the transfer coefficients in fish tissue, the salinity range, and the activity of Cs-137 in water.

  17. Distribution of radioactive caesium in the population of northern Sweden 1988-1993

    International Nuclear Information System (INIS)

    Johansson, L.; Wickman, G.; Aagren, G.; Eriksson, A.; Jonsson, H.; Tavelin, B.

    1995-01-01

    During the period from May 1988 until June 1993 the 137 Cs concentration was measured in 751 samples of psoas muscle from selected medico-legal autopsy cases in the northern half of Sweden. In this area the deposition level of 137 Cs from the Chernobyl accident varied from negligible to 100 kBq.m -2 . Northern Sweden is characterised by large boreal forest areas and a sparse population. The rural population often has a high level of subsistence through meat from reindeer, moose and other game, fresh water fish, forest wild berries and mushrooms. From a multiple linear regression performed on the 137 Cs concentration in the 751 measured samples of human muscle, the effective half-time of caesium whole-body content in the population could be assessed as 3.7 years. A slight increase in 137 Cs concentration was observed with the age of the individual and a significant difference between the sexes, the level for men exceeded that for women by 23%. The dose commitment to this population of approximately 900,000 inhabitants from internal radiation due to the Chernobyl debris could, by this model, be estimated at 220 man.Sv which, with the current ICRP lifetime risk estimates, would cause an addition of ten fatal cancer cases. (author)

  18. Estimates of erosion on potato lands on krasnozems at Dorringo, NSW, using the caesium-137 technique

    International Nuclear Information System (INIS)

    Elliott, G.L.; Cole-Clark, B.E.

    1993-01-01

    Caesium-137 measurements have been made on soil samples taken from a grid pattern in a paddock used for three spring potato crops since 1966. Total erosion was estimated from these measurements and found to average 297 t ha -1 , equivalent to 98 t ha -1 per crop (allowing for erosion during the pasture phase). Comparative erosion estimates have been made from the results of single transect sampling in a paddock used for two potato crops and in one under permanent pasture. Results suggest erosion rates of 57 t ha -1 per crop in the former site and 0.09 t ha -1 year -1 in the latter site. An erosion rate of 100 t ha -1 per crop is at least 100 times the probable soil formation rate, implies an economic resource life of a maximum 600 years and involves a cost of lost nutrients of at least $3200 per hectare. These results strongly suggest a need to both develop and adopt land management practices which will substantially reduce both soil detachment and transport. 19 refs., 3 tabs., 8 figs

  19. A dynamic model of caesium transport in lakes and their catchments

    Energy Technology Data Exchange (ETDEWEB)

    McDougall, Sandra; Jenkins, Alan (Institute of Hydrology, Wallingford (UK)); Hilton, John (Institute of Freshwater Ecology, Ambleside (UK). Windermere Lab.)

    1991-04-01

    A mathematical model has been developed to predict radiocaesium concentrations over time within individual compartments of the lake and its catchment. The lake has been divided into five compartments; catchment, lake water (epilimnion and hypolimnion during stratification), lake sediment and fish. Radiocaesium enters the lake via contaminated rainfall and catchment runoff. A proportion of this radiocaesium absorbs onto suspended solids in the lake. This proportion is represented by a distribution coefficient. Sedimentation of the suspended solids occurs at a rate defined by the areal removal coefficient and results in increased caesium concentrations in the sediment. The ingestion of radiocaesium by either water column or benthic feeding fish is described by transfer functions. The model has been tested against data collected from Esthwaite water and Windermere shortly after the Chernobyl reactor accident from May 1986 to December 1987. The model simulates observed radiocaesium concentrations in Esthwaite lake water and sediment and also in lake water, sediment and fish in Windermere. The model could form the basis of a valuable management tool for the water industry should a major airborne pollution event occur again. (author).

  20. Strontium and caesium transport in unsaturated soil from Chernobyl Pilot Site under steady flow conditions

    International Nuclear Information System (INIS)

    Szenknect, St.

    2003-10-01

    This work is devoted to the quantification and the identification of the predominant processes involved in strontium and caesium transport in unsaturated soil from Chernobyl Pilot Site under steady flow conditions. The transport and fate of radionuclides in the subsurface is affected by various physical and chemical processes including advective and diffusive transport as well as chemical and biological transformations. Laboratory experiments and the use of a multiple tracer approach allow to isolate the contributions of each elementary process and to control the physico-chemical conditions in the system. To be more representative of the field conditions, we decided to perform column miscible displacement experiments. We perform batch and flow-through reactor experiments to characterize the radionuclides sorption mechanisms. Miscible displacement experiments within homogeneous columns and modeling allow to characterize the hydrodynamic properties of the soil and to describe the radionuclides behaviour under dynamic conditions at different water contents. We show that the water content of porous media affect the transport behaviour of inert and strongly sorbing radionuclides. Our results demonstrate that a parametrized transport model that was calibrated under completely saturated conditions was not able to describe the advective-dispersive transport of reactive solutes under unsaturated steady state conditions. Under our experimental conditions, there is no effect of a decrease of the mean water content on the sorption model parameters, but the transport parameters are modified. We established for the studied soil the relation between hydrodynamic dispersion and water content and the relation between pore water velocity and water content. (author)

  1. Mapping of caesium fallout from the Chernobyl accident in the Jotunheimen area

    Energy Technology Data Exchange (ETDEWEB)

    Baranwal, Vikas C.; Ofstad, Frode; Roenning, Jan S.; Watson, Robin J.

    2011-07-01

    As a consequence of the Chernobyl accident, several areas in Norway received radioactive fallout. One of these areas is the eastern part of Jotunheimen in central Norway. Immediately after the accident in 1986, the Geological Survey of Norway (NGU) performed airborne gamma-ray spectroscopy in central Norway. At that time, it was not possible to calculate reliable radionuclide concentrations, and the data were presented as total counts per second. Several man-made radionuclides were present in the initial fallout, but due to short half-lives, most of these have now disintegrated into stable isotopes. 137Cs, with a half-life of 11.000 days ({approx} 30 years) is still present in the environment in significant quantities, leading to high radioactivity levels in meat from reindeer and sheep. To obtain a detailed map of the caesium fallout concentration in Jotunheimen, an airborne gamma-ray spectrometry (AGRS) survey was carried out, focussing on reindeer grazing areas. This project was a cooperation between Reindeer Husbandry Administration, Norwegian Radiation Protection Authority and the Geological Survey of Norway. (auth)

  2. A dynamic model of caesium transport in lakes and their catchments

    International Nuclear Information System (INIS)

    McDougall, Sandra; Jenkins, Alan; Hilton, John

    1991-01-01

    A mathematical model has been developed to predict radiocaesium concentrations over time within individual compartments of the lake and its catchment. The lake has been divided into five compartments; catchment, lake water (epilimnion and hypolimnion during stratification), lake sediment and fish. Radiocaesium enters the lake via contaminated rainfall and catchment runoff. A proportion of this radiocaesium absorbs onto suspended solids in the lake. This proportion is represented by a distribution coefficient. Sedimentation of the suspended solids occurs at a rate defined by the areal removal coefficient and results in increased caesium concentrations in the sediment. The ingestion of radiocaesium by either water column or benthic feeding fish is described by transfer functions. The model has been tested against data collected from Esthwaite water and Windermere shortly after the Chernobyl reactor accident from May 1986 to December 1987. The model simulates observed radiocaesium concentrations in Esthwaite lake water and sediment and also in lake water, sediment and fish in Windermere. The model could form the basis of a valuable management tool for the water industry should a major airborne pollution event occur again. (author)

  3. Radioactive caesium in Boreal forest landscapes - Dynamics and transport in food webs. Summary of research 1986-1996

    Energy Technology Data Exchange (ETDEWEB)

    Bergman, R.; Nylen, T.; Palo, T

    1998-12-01

    The need for - but also the paucity of - radioecological knowledge concerning the boreal forest became particularly apparent after the nuclear power plant accident in Chernobyl in April 1986. As a consequence several new projects were initiated in the Nordic countries with particular focus on the behaviour of radioactivecaesium in terrestrial and aquatic systems characteristic for the Fenno-Scandinavian landscapes. Among these new projects a multi-disciplinary co-operation in Umeaa between scientists at the Swedish University of Agricultural Sciences, and the Defence Research Establishment emerged. Initially this joint work focused mainly on descriptions of the dynamic changes of the content of radioactive caesium in soil-plant and animal communities in the county of Vaesterbotten. Most of the studies have been performed at the Vindeln experimental forest, 60 km NW of Umeaa. Plants of key interest were: bilberry (Vaccinium myrtillus), birch (Betula spp.), and pine (Pinus sylvestris), and among the animals: the moose (Alces alces) and a small rodent, the forest vole (Clethrionomus glareolus). Gradually over the past ten years the research has entered the stage where the specific causes of the caesium behaviour have been addressed - partly by the help of models developed for simulating forest ecosystems, partly by complementary field experiments. This paper reviews our main findings on this theme concerning the behaviour of radioactive caesium in boreal landscapes and significant pathways to man, as has become apparent from the radioecological co-operation dating from about ten years back. A list of the publications arising from these studies since 1986 is also presented in this report.

  4. Theoretical calculations of primary particle condensation for cadmium and caesium iodide vapours

    Energy Technology Data Exchange (ETDEWEB)

    Buckle, E.R. [Division of Metallurgy, School of Materials, The University, Mappin Street, Sheffield S1 3JD (United Kingdom); Bowsher, B.R. [Chemistry Division, Atomic Energy Establishment, Winfrith, Dorchester, Dorset (United Kingdom)

    1988-10-15

    A theoretical approach to modelling aerosol nucleation from the vapour phase has been developed by Buckle. In this theory, the condensing vapour species are assumed to be transported from an evaporating source across a one-dimensional stagnant boundary layer into an unreactive vapour-free atmosphere. A slip-flow model for interfacial energy and mass flow is combined with this stagnant boundary layer model to yield a set of parameters that uniquely characterise the evaporative flow process (i.e. pressure, source and sink temperatures, sink concentration, and the flux density of heat or mass from the source). To obtain the initial conditions for nucleation the vapour saturation ratio p/p deg is plotted against temperature and compared with the minimum saturation ratio defined by homogeneous nucleation theory. The co-education be represented by a nucleation threshold (or F) diagram. The mass and energy equations of the flow are solved by introducing the Becker-Doering formula for the nucleation rate, and the Stefan diffusion model for particle growth. This gives the rise and fall of supersaturation and the evolution of the particle size distribution along the flow coordinate. In the present studies, the applicability of the model has been tested by considering the condensation of caesium iodide and cadmium vapours under a wide variety of pre-mixed flow conditions of interest to PWR severe accident studies. The model has been used to predict the onset of nucleation and the particle size distribution for single vapour species. Preliminary studies have demonstrated that conditions exist whereby both heterogeneous and homogeneous nucleation can occur simultaneously. This process could account for experimental observations of chemically-different aerosols being formed under severe reactor accident conditions. (author)

  5. Baseline Caesium-137 and Plutonium-239+240 inventory assessment for Central Europe

    Science.gov (United States)

    Meusburger, Katrin; Borelli, Pasquale; Evrard, Olivier; Ketterer, Michael; Mabit, Lionel; van Oost, Kristof; Alewell, Christine; Panagos, Panos

    2017-04-01

    Artificial fallout radionuclides (FRNs) such as Caesium-137 and Plutonium-239+240 released as products of the thermonuclear weapons testing that took place from the mid-1950s to the early 1980s and from nuclear power plant accidents (e.g. Chernobyl) are useful tools to quantify soil redistribution. In combination with geostatistics, FRNs may have the potential to bridge the gap between small scale process oriented studies and modelling that simplifies processes and effects over large spatial scales. An essential requirement for the application of FRNs as soil erosion tracers is the establishment of the baseline fallout at undisturbed sites before its comparison to those inventories found at sites undergoing erosion/accumulation. For this purpose, undisturbed topsoil (0-20cm) samples collected in 2009 within the framework of the Land Use/Cover Area frame Survey (LUCAS) have been measured by gamma-spectrometry and ICP-MS to determine 137Cs (n=145) and 239+240Pu (n=108) activities. To restrict the analysis to undisturbed reference sites a geospatial database query selecting only sites having a slope angle <2 degree, outside riparian zones (to avoid depositional sites) and under permanent grassland cover (according to CORINE Land Cover and Landsat) was applied. This study reports preliminary results on the feasibility of establishing a 137Cs and 239+240Pu baseline inventory map for Central Europe. The 137Cs/239+240Pu activity ratios will further allow assessing the rate and the spatial variability of 137Cs Chernobyl fallout. The establishment of such baseline inventory map will provide a unique opportunity to assess soil redistribution for a comparable time-frame (1953-2009) following a harmonised methodological protocol across national boundaries.

  6. The assessment of soil redistribution on agricultural land using the environmental isotope of Caesium-137

    International Nuclear Information System (INIS)

    Zainudin Othman

    2002-01-01

    Environmental radionuclides have the potential to be used to trace sediment movements. Caesium-137 ( 137 Cs), a radionuclide released during nuclear weapon tests from 1950s to 1960s is strongly adsorbed on to clay. It enters the Malaysian environment through cold continental polar (cPk) air mass circulation and Hadley cell effects from the higher latitude regions, converged during Inter-tropical Convergence Zones (ITCZ) oscillation and deposited through precipitation on to the soil as fallouts. Its content in the soil profile has been used to estimate soil loss due to water erosion in agricultural land. Two soil sampling methods, incremental and bulk sampling, were adopted to collect samples from the erosion plot and reference sites to a depth of 40 cm for the determination of 137 Cs inventories. The soil depth-profile of 137 Cs inventory at an undisturbed site exhibits an exponential function with most of the contents are accumulated within the upper 12 cm portion of the soil profile whereas in the disturbed sites the 137 Cs content were partially mixed within the plough layer. The average 137 Cs reference inventory from two different locations was 580.7 Bq/ m 2 while local 137 Cs reference inventory was 551.9 Bq/ m 2 . The USLE, Ritchie equation and three mathematical models were used to estimate the rate of soil loss. The Proportional Model was found suitable to be used in this environment. Net soil loss from the study slope was estimated by the USLE of 4.34 ton/ ha/ yr. The soil redistribution patterns show that the upper and middle slopes had been eroded while deposition was observed at the foot slope. The maximum land form evolutions of the eroded areas was 4.5 mm/ yr and 0.5 mm/ yr for the depositional areas. The long-term erosion rate of the study area was considered low. (author)

  7. Results of several years experiments on the absorption of radioactive strontium and caesium by cultivated plants (1962)

    International Nuclear Information System (INIS)

    Michon, M.; Fioramonti, M.; Marty, M.; Barbier, M.; Le Blaye, M.; Brossard, M.

    1962-01-01

    This report follows on to the report number CEA 1860 and uses results obtained in 1960 to give more precise details concerning the data presented in the preceding report. First results obtained on the vine are given. The Sr absorption coefficient has varied very little from one year to the next and that of caesium has slightly diminished. The values obtained suggest that the concentrations of 90 Sr and 137 Cs in irrigation water should not exceed 1/5 of the maximum permissible concentration in drinking water. (authors) [fr

  8. A survey of radioactive caesium in soils of Cumbria and North Lancashire

    International Nuclear Information System (INIS)

    Baker, S.J.; Cawse, P.A.

    1990-09-01

    A network of soil sampling sites covering an area of some 2500km 2 in Cumbria was sampled by Harwell Laboratory in 1978. The spatial distribution of sampling points was based on a grid of 10km side, thus providing 30 sites under permanent grassland. In 1979, the grid was extended northwards to Carlisle and in a southerly direction to Fleetwood, Lancashire, giving a further 24 sites. This provided a reference baseline of background radioactivity, mainly arising from the accumulated atmospheric deposition of fallout from nuclear weapons tests over some 30 years, and also determined the distribution of emissions from the nuclear establishment at Sellafield that is superimposed upon the natural background of radioactivity in soil. The grid survey has now been repeated in 1988/89 to record increases in radioactive caesium caused by fallout from the accident at Chernobyl, USSR, in April 1986. The accumulated depositions of 137 Cs recorded to 30cm soil depth in 1988/89 were in the range 2.0 (at Bowness on Solway) to 28kBq/m 2 (at Eskmeals). A comparison of results obtained pre-Chernobyl (in 1978) with post-Chernobyl values assessed ten years later shows increases of 137 Cs accumulations at 18 of the surveys sites, 1.5 to 2-fold at 20 sites, 2 to 4 fold at 13 sites and 4 to 7 fold at St Bees, Harrington and Little Annaside (near Bootle, Cumbria). Ratios of Cs-137/Cs-134 at 0-15cm depth of soil were in the range 3.0 - 26.4 in 1988/89, compared with a ratio of ∼ 3.0 in Chernobyl fallout when decay-corrected. Lowest ratios occurred in west Cumbria which showed the highest accumulations of Cs-137 between 290-330km easting and 480-530km northing. The retention of Cs-137 by the top 15cm of soil in 1988/89 relative to the accumulation to 30cm depth averaged 87% compared with 78% in the pre-Chernobyl survey made in 1978/79, and is attributed to surface accumulation of debris from the accident. (author)

  9. 137 Caesium distribution in the eastern Mediterranean Sea. Recent changes and future trends

    International Nuclear Information System (INIS)

    Papucci, C.; Delfanti, R.

    1999-01-01

    A series of sampling campaigns were carried out in the eastern Mediterranean in the period 1995-1997, to examine the relationship between the distribution of 137Cs in the water column and water mass circulation. 137Cs concentration in the surface water ranges between 3.3 and 4.0 mBq/l all over the area, indicating that the input due to the Chernobyl accident has been transferred to deep water layers by convection processes. In fact, in the vertical profiles, relative maxima are observed in the intermediate (4 mBq/l) and deep waters (∼2.5 mBq/l) formed after the Chernobyl accident. A clear Chernobyl signal also traces the new deep waters formed in the Aegean Sea that, exiting from the Cretan Arc Straits, since 1991 are spreading in the bottom layer of the eastern Mediterranean. The changes in 137Cs vertical profiles related to the new thermohaline circulation of the intermediate and deep waters of the eastern Mediterranean are being monitored at a deep station in the western Ionian Sea. The 1997 profile shows a decrease in 137Cs concentration both in the Levantine intermediate water and in the eastern Mediterranean deep water with respect to 1996. The decrease in Levantine intermediate water is likely due to seasonal/interannual variability, while the changes in the deep layer are related to the spreading westward into the Ionian of the new Aegean dense water. Along the path towards the western Mediterranean, 137Cs content in the Levantine intermediate water decreases from ∼4 mBq/l in the W-Ionian Sea to ∼2 mBq/l at the western sill of the Sicily Straits, due to mixing with underlying water, with lower caesium content, near the Malta Sill. Time-series measurements at the western sill of the Sicily Straits show that, while 137Cs concentration in the surface water entering the eastern Mediterranean remained constant (∼3.5 mBq/l) in the period 1993-1997, its level in the Levantine intermediate water leaving the basin decreased from 3.5 to 2.0 mBq/l

  10. Analysis of the kinetic behaviour of iodine and caesium isotopes in the primary circuit of LWR's during severe fuel damage accidents

    International Nuclear Information System (INIS)

    Alonso, A.; Fernandez, S.; Buron, J.M.; Lopez, J.V.

    1991-01-01

    This State of the Art report deals with the chemical behaviour of caesium and iodine in the primary system, focusing particularly on kinetic chemical aspects. In case of a postulated severe accident in a nuclear reactor, cesium and iodine fission products are among the major contributors to health harm because of their high volatility and radiotoxicity. The extent of the release of such fission products to the environment depends on the effectiveness of transport through different structures in the reactor coolant system and within the reactor building. The release from fuel has been briefly studied; only those aspects concerning to iodine and caesium chemical forms when released have been reviewed; nevertheless the emphasis has been put on the transport of such elements and their species through the primary system. Some thermochemical equilibrium studies, applied to primary circuit conditions in LWR's, have been analyzed. The revision of the few kinetic studies existing on this matter has shown that kinetic behaviour of iodine and caesium isotopes in the primary circuit is an aspect poorly studied, despite the fact that kinetic aspects could have great importance on the chemical species formed under certain conditions. Other phenomena affecting iodine and caesium transport, besides chemical reactions, such as interactions with surfaces, aerosols or other chemical species have also been examined from available information on diverse experiments

  11. A comparison using the caesium-137 technique of the relative importance of cultivation and overland flow on soil erosion in a steep semi-tropical sub-catchment

    International Nuclear Information System (INIS)

    Wiranatha, A.S.; Rose, C.W.; Salama, M.S.

    2001-01-01

    The spatial pattern of net soil loss on 6 downslope transects in a small semi-tropical sub-catchment was measured in 1990-91 using the resident caesium-137 deficit technique. The sub-catchment consisted of 2 opposing hillslopes which shed water to an intermittent stream in the valley bottom of the sub-catchment. There were 3 transects on each of the opposing hillslopes, and measurement indicated net soil loss from all 6 transects. Furthermore, the spatial pattern of caesium- 37 deficit did not indicate the accumulation of soil expected due to the slope decrease toward the bottom of the valley. Possible explanations of this finding could be the effect of periodic flooding of the intermittent valley stream, or seepage-accelerated erosion. Pineapple cultivation in the sub-catchment since 1950 included intensive cultivation at 4-year intervals by downslope-moving rotary hoe. The paper develops a theoretical prediction of the spatial pattern of net soil loss expected due to such cultivation, as well as the expected pattern of soil loss due to overland flow on the hillslopes. The spatial patterns of soil loss due to these 2 different soil erosion mechanisms were then compared with the pattern of net soil loss indicated by caesium- 137 depletion to provide an assessment of their likely relative importance in contributing to soil loss. In the upper part of each hillslope, this comparison of spatial trends did not allow the dominant cause of soil erosion to be distinguished. Both the model of erosion due to cultivation and that due to hillside overland flow predicted soil accumulation in the lower valley sides where slope decreased. Neither model represented the net loss of such accumulated soil indicated by caesium- 137 deficit, and this loss possibly occurred during periodically observed flooding of the valley floor, or due to surface burial with caesium-137 depleted subsoil. Copyright (2001) CSIRO Publishing

  12. Density functional theory metadynamics of silver, caesium and palladium diffusion at β-SiC grain boundaries

    Energy Technology Data Exchange (ETDEWEB)

    Rabone, Jeremy, E-mail: jeremy.rabone@ec.europa.eu [European Commission, Joint Research Centre, Institute for Transuranium Elements, D-76125 Karlsruhe (Germany); López-Honorato, Eddie [Centro de Investigación y de Estudios Avanzados del IPN (CINVESTAV), Unidad Saltillo, Industria Metalúrgica 1062, Parque Industrial, Ramos Arizpe 25900, Coahuila (Mexico)

    2015-03-15

    Highlights: • DFT metadynamics of diffusion of Pd, Ag and Cs on grain boundaries in β-SiC. • The calculated diffusion rates for Pd and Ag tally with experimental release rates. • A mechanism of release other than grain boundary diffusion seems likely for Cs. - Abstract: The use of silicon carbide in coated nuclear fuel particles relies on this materials impermeability towards fission products under normal operating conditions. Determining the underlying factors that control the rate at which radionuclides such as Silver-110m and Caesium-137 can cross the silicon carbide barrier layers, and at which fission products such as palladium could compromise or otherwise alter the nature of this layer, are of paramount importance for the safety of this fuel. To this end, DFT-based metadynamics simulations are applied to the atomic diffusion of silver, caesium and palladium along a Σ5 grain boundary and to palladium along a carbon-rich Σ3 grain boundary in cubic silicon carbide at 1500 K. For silver, the calculated diffusion coefficients lie in a similar range (7.04 × 10{sup −19}–3.69 × 10{sup −17} m{sup 2} s{sup −1}) as determined experimentally. For caesium, the calculated diffusion rates are very much slower (3.91 × 10{sup −23}–2.15 × 10{sup −21} m{sup 2} s{sup −1}) than found experimentally, suggesting a different mechanism to the simulation. Conversely, the calculated atomic diffusion of palladium is very much faster (7.96 × 10{sup −11}–7.26 × 10{sup −9} m{sup 2} s{sup −1}) than the observed penetration rate of palladium nodules. This points to the slow dissolution and rapid regrowth of palladium nodules as a possible ingress mechanism in addition to the previously suggested migration of entire nodules along grain boundaries. The diffusion rate of palladium along the Σ3 grain boundary was calculated to be slightly slower (2.38 × 10{sup −11}–8.24 × 10{sup −10} m{sup 2} s{sup −1}) than along the Σ5 grain boundary. Rather

  13. [Reduction of 137caesium contamination in wild boars by supplementing offered food with ammonium-iron-hexa-cyanoferrate].

    Science.gov (United States)

    Morfeld, P; Reddemann, J; Schungel, P; Kienzle, E

    2014-01-01

    This replication study investigated whether the 137caesium (137Cs) contamination of wild boars could be relevantly reduced under field conditions by adding ammonium-iron-hexa-cyanoferrate (AFCF; Prussian blue) to the food. In 285 wild boars that had been shot in six Bavarian hunting territories during the season (November until May) between 01 November 2010 and 10 December 2011 137Cs contamination was analysed. Thirty-five animals originated from two hunting territories in which offered food had been supplemented with 1250 mg AFCF per kilogram food. The control animals showed a mean 137Cs contamination of 522 Bq/kg lean skeletal muscle meat. Direct (univariable) comparisons of the two experimental territories with the four control territories yielded a mean reduction in 137Cs contamination due to Prussian bluefeeding by -211 Bq/kg (p contamination by -380 Bq/kg due to the feeding of Prussian blue in other territories.

  14. Promotion of radiation peroxidation in models of lipid membranes by caesium and rubidium counter-ions: micellar linolenic acids

    Energy Technology Data Exchange (ETDEWEB)

    Raleigh, J A; Kremers, W [Atomic Energy of Canada Ltd., Pinawa, Manitoba. Whiteshell Nuclear Research Establishment

    1978-11-01

    Caesium and rubidium counter-ions increase peroxidation in irradiated micelles of linoleic (18 : 2) and linolenic (18 :3) acids. The effect was specific to Cs/sup +/ and Rb/sup +/ in the alkali metal series. The effect was independent of the salts used (Cl/sup -/, NO/sub 3//sup -/, Cl0/sub 4//sup -/) and, therefore, independent of the chaotropic nature, and reactivity with hydroxyl radicals of Cl/sup -/, NO/sub 3//sup -/ and ClO/sub 4//sup -/. The promotion of peroxidation by Cs/sup +/ and Rb/sup +/ is interpreted in terms of their effect on fatty acid micelle structure. The dependence of radiation peroxidation on lipid structure in the micelles may be significant for studies of peroxidation in highly structured cell membranes.

  15. Wiedemann-Franz ratio in high-pressure and low-temperature thermal xenon plasma with 10% caesium

    International Nuclear Information System (INIS)

    Novakovic, N.V.; Milic, B.S.; Stojilkovic, S.M.

    1995-01-01

    Theoretical investigations of various transport properties of low-temperature noble-gas plasmas with additives has aroused a continuous interest over a considerable spall of time, due to numerous applications. In this paper the results of a theoretical evaluation of electrical conductivity, thermal conductivity and their ratio (the Wiedemann-Franz ratio) in xenon plasma with 10% of argon and 10% of caesium are presented, for the temperature range from 2000 K to 20000 K, and for pressures equal to or 5, 10, and 15 time higher than the normal atmospheric pressure. The plasma was regarded as weakly non-ideal and in the state of local thermodynamical equilibrium with the assumption that the equilibrium is attained with the pressure kept constant. The plasma composition was determined on the ground of a set of Saha equations; the ionization energy lowerings were expressed with the aid of a modified plasma Debye radius r* D (rather than the standard r D ), as proposed previously

  16. The effect of organics on the sorption of strontium, caesium, iodine, neptunium, uranium and europium by glacial sand

    International Nuclear Information System (INIS)

    Haigh, D.; Higgo, J.J.W.; Williams, G.M.; Hooker, P.J.; Ross, C.A.M.; Falck, W.E.; Allen, M.A.; Warwick, P.

    1991-01-01

    This study has been undertaken within the Commission of the European Communities MIRAGE II program on the determination of radionuclides in the geosphere. Preliminary batch sorption experiments have been carried out to study the behaviour of strontium, caesium, iodine, europium and uranium in a glacial sand-groundwater system. The effect of (i) the presence or absence of natural organic material and (ii) the addition of increasing quantities of EDTA or acetate on the distribution ratios was determined. In some cases speciation modelling was used as an aid to designing the experiments and interpreting the results. The aim of this work was to select suitable tracers for use in field experiments at Drigg. Cumbria and the results are intended to aid the design of future experiments rather than to provide a complete analysis of the radionuclide-organic interactions. 11 tabs., 49 refs

  17. Industrial treatment of solutions of fission products. Separation of caesium-137; Traitement industriel de solutions de produits de fission. Separation du cesium-137

    Energy Technology Data Exchange (ETDEWEB)

    Fisher, C; Raggenbass, A [Commissariat a l' Energie Atomique, Saclay (France).Centre d' Etudes Nucleaires

    1959-07-01

    Two types of chemical treatment can be considered for the manufacture of solid sources for industrial uses from fission product solutions remaining after plutonium extraction: a) concentration of the solution and preparation of solid sources from the bulk material, without separation, b) separation of one or several fission products from which the sources are made. Examination of the radio-chemical composition of the mixture of fission products that will be available from the Marcoule reactors (G1, G2 and G3) shows that caesium-137 accounts for 30 per cent of the {gamma} energy available immediately after the plutonium separation, 70 per cent two years after and 100 per cent after five years. There is practically no advantage in making sources from bulk fission products, since the separation of caesium-137 is no more complicated and yet it results in a material with more potential uses. The separation of caesium-137 by a method based on the standard phospho-tungstate precipitation method has been considered. Previously, the precipitated caesium phospho-tungstate was dissolved and caesium was recovered from the solution by cation-exchange or by removal of phosphate and tungstate ions by anion-exchange. A study has now been made, of the metathesis of caesium phospho-tungstate to barium phosphate and tungstate by the action of barium hydroxide, the caesium being obtained in solution as the hydroxide. The advantages of this new procedure are: - greater decontamination of caesium-137 without further purification, - possibility of direct transformation to caesium sulphate, - general simplification of the procedure and, consequently, of the equipment. (author) [French] Deux types de traitement chimique peuvent etre envisages pour amener a l'etat de sources solides utilisables industriellement les produits de fission contenus dans les solutions residuaires de l'extraction du plutonium. Ces traitements sont les suivants: a) concentration des solutions et confection de

  18. Industrial treatment of solutions of fission products. Separation of caesium-137; Traitement industriel de solutions de produits de fission. Separation du cesium-137

    Energy Technology Data Exchange (ETDEWEB)

    Fisher, C.; Raggenbass, A. [Commissariat a l' Energie Atomique, Saclay (France).Centre d' Etudes Nucleaires

    1959-07-01

    Two types of chemical treatment can be considered for the manufacture of solid sources for industrial uses from fission product solutions remaining after plutonium extraction: a) concentration of the solution and preparation of solid sources from the bulk material, without separation, b) separation of one or several fission products from which the sources are made. Examination of the radio-chemical composition of the mixture of fission products that will be available from the Marcoule reactors (G1, G2 and G3) shows that caesium-137 accounts for 30 per cent of the {gamma} energy available immediately after the plutonium separation, 70 per cent two years after and 100 per cent after five years. There is practically no advantage in making sources from bulk fission products, since the separation of caesium-137 is no more complicated and yet it results in a material with more potential uses. The separation of caesium-137 by a method based on the standard phospho-tungstate precipitation method has been considered. Previously, the precipitated caesium phospho-tungstate was dissolved and caesium was recovered from the solution by cation-exchange or by removal of phosphate and tungstate ions by anion-exchange. A study has now been made, of the metathesis of caesium phospho-tungstate to barium phosphate and tungstate by the action of barium hydroxide, the caesium being obtained in solution as the hydroxide. The advantages of this new procedure are: - greater decontamination of caesium-137 without further purification, - possibility of direct transformation to caesium sulphate, - general simplification of the procedure and, consequently, of the equipment. (author) [French] Deux types de traitement chimique peuvent etre envisages pour amener a l'etat de sources solides utilisables industriellement les produits de fission contenus dans les solutions residuaires de l'extraction du plutonium. Ces traitements sont les suivants: a) concentration des solutions et

  19. Caesium-137 in Marine Sediments of the Eastern Mediterranean from the Pre-Chernobyl Age to the Present

    International Nuclear Information System (INIS)

    Florou, Heleny; Evangeliou, Nikolaos; Kritidis, Panagiotis

    2011-01-01

    Caesium-137 (half-life 30.2 years) was first introduced into the marine environment as a result of the atmospheric nuclear weapon testing during 1953-1963. The second and largest contamination was the fallout after the Chernobyl accident in April 1986. Since 1986 the radiological status of the Mediterranean has been changed. During 1986 the average deposition of 137 Cs from the fallout in the Aegean Sea has been estimated to be approximately 4 kBq m -2 , whereas the respective value for the Ionian Sea (the area of 24,300 km 2 along the coasts) was 2.5 kBq m -2 . The total caesium ( 137 Cs + 134 Cs) input from Chernobyl fallout has been estimated to be 2400 TBq for the Black Sea, 820 TBq for the Aegean Sea and 600 TBq in the Ionian Sea (60 TBq in the zone of 50 km across the coasts). Although, the residence time of 137 Cs in seawater is long, it has been observed that 137 Cs has reached the bottom sediments, as the remaining period is long enough if compared to the estimated sinking time for the Mediterranean environment. The Mediterranean Sea is a semi-enclosed marine area, exchanging water, salt, heat and other physicochemical properties through the strait of Gibraltar with the Atlantic Ocean.The basin is characterized by low precipitation and high evaporation, which causes accumulation of contaminants in seawater and sediment. Taking into account the topography,one could note the importance of the eastern part of the Mediterranean,since it comprises a continuous source of interregional input (Black Sea). However,the motive of determining 137 Cs in the Greek marine territory was basic research (pre-Chernobyl age) and monitoring reasons (after Chernobyl accident). Several Greek marine systems have been examined throughout these years and the results are evaluated in the present study.

  20. Theoretical investigations of the fission product release out of the core of a high temperature reactor during hypothetical heat up accidents as example of caesium

    International Nuclear Information System (INIS)

    Batalas, T.A.; Iniotakis, N.; Decken, C.B. von der.

    1986-03-01

    The investigation has been performed by means of a physical model, taking into account the micro- and macro-structures of the pyrolytical and graphitical reactor components as well as renouncing an introduction of effective diffusion coefficients by the description of the fission products transport through the coated particle layers and the fuel elements and renouncing an assumption of the spontaneously adsorption-desorption equilibrium on the surface of the fuel elements. The solving method and the respective computer codes were also developed. In addition the theoretically calculated and the experimentally determined results regarding the caesium release from single coated particles as well as fuel elements at accident temperatures were compared. Finally the caesium release from the core of the PNP-500 reactor during a heat up accident has been estimated and discussed. (orig./HP) [de

  1. Development of a kinetic model, including rate constant estimations, on iodine and caesium behaviour in the primary circuit of LWR's under accident conditions

    International Nuclear Information System (INIS)

    Alonso, A.; Buron, J.M.; Fernandez, S.

    1991-07-01

    In this report, a kinetic model has been developed with the aim to try to reproduce the chemical phenomena that take place in a flowing system containing steam, hydrogen and iodine and caesium vapours. The work is divided into two different parts. The first part consists in the estimation, through the Activited Complex Theory, of the reaction rate constants, for the chosen reactions, and the development of the kinetic model based on the concept of ideal tubular chemical reactor. The second part deals with the application of such model to several cases, which were taken from the Phase B 'Scoping Calculations' of the Phebus-FP Project (sequence AB) and the SFD-ST and SFD1.1 experiments. The main conclusion obtained from this work is that the assumption of instantaneous equilibrium could be inacurrate in order to estimate the iodine and caesium species distribution under severe accidents conditions

  2. Resonant multiphoton ionization of caesium atoms by ultra-short laser pulses at 1.06 μm

    International Nuclear Information System (INIS)

    Lompre, L.A.; Mainfray, G.; Manus, C.; Thebault, J.

    1978-01-01

    This paper reports the four-photon ionization of caesium atoms when the laser frequency is tuned through the resonant three-photon transition 6S → 6F. This experiment was performed by using a tunable-wavelength bandwidth-limited subnanosecond laser pulse at 1.06 μm, in the 10 8 -10 9 W.cm -2 laser intensity range. Pulse widths of 1.5 ns, 50 ps, and 15 ps were used. The resonant character of the multiphoton ionization process was observed, even with the shortest pulse of 15 ps. Nevertheless the influence of a temporal effect is demonstrated according to theoretical predictions. The resonance shift ΔE of the 6S → 6F transition energy was found to be linear with the laser intensity I within the range 10 8 -10 9 W.cm -2 . ΔE = αI, with α = 2 cm -1 /GW.cm -2 . This results confirms previous measurements performed with single-mode 35 ns laser pulses and is in very good agreement with calculated resonance shifts

  3. Reduction of 137caesium contamination in wild boars by supplementing offered food with ammonium-iron-hexa-cyanoferrate

    International Nuclear Information System (INIS)

    Morfeld, P.; Kienzle, E.

    2014-01-01

    This replication study investigated whether the 137 caesium ( 137 Cs) contamination of wild boars could be relevantly reduced under field conditions by adding ammonium-iron-hexa-cyanoferrate (AFCF; Prussian blue) to the food. In 285 wild boars that had been shot in six Bavarian hunting territories during the season (November until May) between 01 November 2010 and 10 December 2011 137 Cs contamination was analysed. Thirty-five animals originated from two hunting territories in which offered food had been supplemented with 1250 mg AFCF per kilogram food. The control animals showed a mean 137 Cs contamination of 522 Bq/kg lean skeletal muscle meat. Direct (univariable) comparisons of the two experimental territories with the four control territories yielded a mean reduction in 137 Cs contamination due to Prussian bluefeeding by -211 Bq/kg (p < 0.001). Multivariable mo dels that took potential confounders into account (age, weight, sex, hunting date, territory) estimated the effect to be -344 Bq/kg (p < 0.05). This replication study confirmed the finding of Kienzle et al. (12) who described a statistically significant reduction in 137 Cs contamination by -380 Bq/kg due to the feeding of Prussian blue in other territories. [de

  4. The caesium 137 content in the water of the North Sea during the years 1969 to 1975

    International Nuclear Information System (INIS)

    Kautsky, H.

    1976-01-01

    In April 1975, about 34,000 Ci Caesium 137 in a water mass of about 30,500 km 3 was found in the area of the North Sea that we investigated between 51 0 N to 60 0 N and 4 0 W to 10 0 E. This represented a mean concentration of about 1.1 Ci/km 3 or 1.1 pCi/l water. Concentration variations of between 0.44 to 2.2 pCi/l in the different areas of the North Sea were measured. As compared with ICRP Standards, 137 Cs concentrations in sea water of up to some 900 pCi/l may be viewed as a still permissible limit (IAEA, 1970). The development of the 137 Cs content in the North Sea from 1969 to 1975 is discussed. Especially, the temporal changes in concentrations in different sections of the North Sea will be compared. These clearly show the different influence in different sections of the radioactive waste waters of the three coastal European nuclear fuel reprocessing plants on the content of radioactive fission products as well as their spreading in the water of the North Sea. (orig./HP) [de

  5. Caesium-rich micro-particles: A window into the meltdown events at the Fukushima Daiichi Nuclear Power Plant

    Science.gov (United States)

    Furuki, Genki; Imoto, Junpei; Ochiai, Asumi; Yamasaki, Shinya; Nanba, Kenji; Ohnuki, Toshihiko; Grambow, Bernd; Ewing, Rodney C.; Utsunomiya, Satoshi

    2017-02-01

    The nuclear disaster at the Fukushima Daiichi Nuclear Power Plant (FDNPP) in March 2011 caused partial meltdowns of three reactors. During the meltdowns, a type of condensed particle, a caesium-rich micro-particle (CsMP), formed inside the reactors via unknown processes. Here we report the chemical and physical processes of CsMP formation inside the reactors during the meltdowns based on atomic-resolution electron microscopy of CsMPs discovered near the FDNPP. All of the CsMPs (with sizes of 2.0-3.4 μm) comprise SiO2 glass matrices and ~10-nm-sized Zn-Fe-oxide nanoparticles associated with a wide range of Cs concentrations (1.1-19 wt% Cs as Cs2O). Trace amounts of U are also associated with the Zn-Fe oxides. The nano-texture in the CsMPs records multiple reaction-process steps during meltdown in the severe FDNPP accident: Melted fuel (molten core)-concrete interactions (MCCIs), incorporating various airborne fission product nanoparticles, including CsOH and CsCl, proceeded via SiO2 condensation over aggregates of Zn-Fe oxide nanoparticles originating from the failure of the reactor pressure vessels. Still, CsMPs provide a mechanism by which volatile and low-volatility radionuclides such as U can reach the environment and should be considered in the migration model of Cs and radionuclides in the current environment surrounding the FDNPP.

  6. Long range transport of caesium isotopes from temperate latitudes to the equatorial zone during the winter monsoon period

    International Nuclear Information System (INIS)

    Pham Duy Hien; Nguyen Thanh Binh; Vuong Thu Bac; Truong Y; Nguyen Trong Ngo.

    1993-01-01

    An air radioactivity monitoring study carried out in Dalat, Vietnam since 1986 has revealed distinct peaks of caesium isotope concentrations in air and fallout during December-January, when the monthly average air temperature was lowest and dry fallout dominated. These peaks provide evidence of the intrusion of more radioactive cold air masses from temperate northern latitudes during the development of large-scale anti cyclones, frequently observed in the most active winter monsoon period. High dry fallout velocity (about 10 cm/s) determined from the measured concentrations, clearly demonstrates one of the most relevant features of cold air masses: behind the cold front, vertical air motion is descending. The role of other processes, such as injection of radioactive air from stratosphere and local resuspension of soil dust, has been shown to be insignificant. The interpretation of the experimental results was based on the analysis of environmental -meteorological factors as well as the behaviour of other naturally-occurring radionuclides. (author). 7 refs, 2 figs

  7. Can inter-cultivar variation in caesium and strontium uptake reduce contamination of forage grasses? - Can inter-cultivar variation in caesium and strontium accumulation by forage grasses be used to reduce contamination of cows' milk in radiologically contaminated areas?

    Energy Technology Data Exchange (ETDEWEB)

    Penrose, B. [NERC Centre for Ecology and Hydrology, Lancaster Environment Centre, Library Avenue, Lancaster, LA1 4AP (United Kingdom); School of Biosciences, University of Nottingham, Sutton Bonington Campus, Leicestershire, LE12 5RD (United Kingdom); Beresford, N. [NERC Centre for Ecology and Hydrology, Lancaster Environment Centre, Library Avenue, Lancaster, LA1 4AP (United Kingdom); Broadley, M.; Crout, N.M.J.; King, J.; Young, S. [School of Biosciences, University of Nottingham, Sutton Bonington Campus, Leicestershire, LE12 5RD (United Kingdom); Lovatt, A. [Institute of Biological, Environmental and Rural Sciences (IBERS), Aberystwyth University, Gogerddan, Aberystwyth, Ceredigion, SY23 3E E (United Kingdom); Thomson, R. [Science and Advice for Scottish Agriculture (SASA), Roddinglaw Road, Edinburgh, EH12 9FJ (United Kingdom)

    2014-07-01

    Radiocaesium and radiostrontium primarily enter the food chain via plant root uptake, including indirectly via animal fodders. Inter-species variation in caesium and strontium accumulation in plants has previously been reported to be over two orders of magnitude. This variation could be exploited to select crops with relatively low uptake to reduce transfer of these radionuclides to consumers in contaminated areas. Exploiting intra-species (i.e. inter-cultivar) variation in caesium and strontium uptake has not yet been evaluated as a remediation strategy as sufficient data have not been available. As cows' milk has been one of the main contributors to human dose following the Chernobyl and Mayak accidents, we have chosen to focus on elucidating the extent and nature of inter-cultivar variation in caesium and strontium uptake in forage grasses. A total of 412 cultivars from four species of forage grass; perennial ryegrass (Lolium perenne; 284 cultivars), Italian ryegrass (Lolium multiflorum; 17 cultivars), hybrid ryegrass (Lolium hybridum; 101 cultivars) and tall fescue (Festuca arundinacea; 10 cultivars) were sampled from 20 sets of experimental plots in Aberystwyth (Wales, UK) and Edinburgh (Scotland, UK). Fifty-nine cultivars were grown in both locations. At least three replicates of the same cultivar were grown in each set of plots. Vegetation samples from 2208 plots were collected both in spring 2013 (May-June) and summer 2013 (August-September). The samples were oven-dried and milled then analysed for elemental composition using inductively coupled plasma mass spectrometry (ICP-MS). Stable caesium and strontium were measured as a proxy measurement for radiocaesium and radiostrontium concentrations. Concentrations of chemical analogues of caesium and strontium (potassium and calcium) and a number of other elements were measured. Soil samples from the experimental plots were also collected, dried, milled and analysed using ICP-MS. This paper will present

  8. Caesium 137: Properties and biological effects resulting of an internal contamination;Cesium 137: proprietes et effets biologiques apres contamination interne

    Energy Technology Data Exchange (ETDEWEB)

    Lestaevel, P.; Racine, R.; Bensoussan, H.; Rouas, C.; Gueguen, Y.; Dublineau, I.; Bertho, J.M.; Gourmelon, P.; Jourdain, J.R.; Souidi, M. [Institut de Radioprotection et de Surete Nucleaire, IRSN, laboratoire de radiotoxicologie experimentale, direction de la radioprotection de l' homme, 92 - Fontenay-aux-Roses (France)

    2010-02-15

    Caesium-137 ({sup 137}Cs) is a radionuclide present in the environment mainly as the result of the atmospheric nuclear weapons testing and accidents arising in nuclear power plants like the Chernobyl accident in 1986. Nowadays, the health consequences resulting from a chronic exposure to this radionuclide remain unknown. After absorption, the caesium is distributed relatively homogeneously within the body, with a more important load in children than in adults. The toxicity of {sup 137}Cs is mainly due to its radiological properties. A high dose of {sup 137}Cs is responsible for a medullar dystrophy, disorders of the reproductive function, and effects on liver and renal functions. Disorders of bone mineralization and brain damages were also described in human beings. At lowest dose, {sup 137}Cs induces disturbances of wakefulness-sleep cycle, but not accompanied with behavioural disorders. The cardiovascular system was also perturbed. Biological effects of {sup 137}Cs on the metabolisms of the vitamin D, cholesterol and steroid hormones were described, but do not lead to clinical symptoms. In human beings, {sup 137}Cs leads to an immune deficiency, congenital and foetal deformations, an increased of thyroid cancer, as well as neurological disorders. It seems that children are more sensitive to the toxic effects of caesium than the adults. At present, the only effective treatment for the decorporation of the ingested {sup 137}Cs is the Prussian Blue (Radiogardase). The use of pectin to de-corporate the ingested {sup 137}Cs, in children notably, is sometimes proposed, but its administration still remains an open question. To conclude, the available scientific data suggest that {sup 137}Cs could affect a number of physiological and metabolic functions and consequently, could participate in the health risks associated to the presence of other contaminants in the environment. (authors)

  9. Radiological effect of caesium-137 and strontium-90 on aquatic system of the pathway of the discharged liquid radioactive waste

    International Nuclear Information System (INIS)

    Sinakhom, F.; Pothipin, K.; Supaokit, P.

    1984-12-01

    The objective of this paper is to study the radiological effect from the release of treated liquid radioactive waste to the fresh water environment in order to the protection of human health. The emphasis in this program was concentrated on Sr-90 and Cs-137 analyses on Sr-90 and Cs-137 analyses in surface water, water-plants and fish collected during August 1980 to July 1981. Sr-90 concentration was separated by solvent extraction (TBP-tributyl phosphate) procedure. Beta radioactivity of the two nuclides were measured in the form of yttrium oxalate (Y-90, the daughter nuclide of Sr-90) and caesium phospho-molybdate using a low-background anticoincidence proportional counter. To interpret the result obtained, the analytical data were converted to percent derived working limits (%DWL) using Derived Working Limit acquired from the value of (MPC) and water consumption rate stipulated by ICRP as 100% DWL. The value of %DWL is a useful and convenient index to judge the hazardous from radiation exposed by a certain group of people. The interpretation of the result revealed the equivalence of %DWL of Sr-90 and Cs-137 in canal-fish and swamp cabbage for people resided nearby the canal who obtained their whole protein from consumption of that fish from canal and vegetation grown in that water. The value above was equal 2.5 percent which means that this critical group of people exposed to the radiation only 2.5 percent of that intake limit recommended by ICRP. Thus, the amounts of waste disposed of from waste treatment plant into the canal were too small to have a radiological effect on the environment

  10. Forage grasses with lower uptake of caesium and strontium could provide ‘safer’ crops for radiologically contaminated areas

    Science.gov (United States)

    Beresford, Nicholas A.; Crout, Neil M. J.; Lovatt, J. Alan; Thomson, Russell; Broadley, Martin R.

    2017-01-01

    Substitution of a species or cultivar with higher uptake of an element by one with lower uptake has been proposed as a remediation strategy following accidental releases of radioactivity. However, despite the importance of pasture systems for radiological dose, species/cultivar substitution has not been thoroughly investigated for forage grasses. 397 cultivars from four forage grass species; hybrid ryegrass (Lolium perenne L. x Lolium multiflorum Lam.), perennial ryegrass (Lolium perenne L.), Italian ryegrass (Lolium multiflorum Lam.) and tall fescue (Festuca arundinacea Shreb.); were sampled from 19 field-based breeding experiments in Aberystwyth and Edinburgh (UK) in spring 2013 and analysed for caesium (Cs) and strontium (Sr) concentrations. In order to calculate concentration ratios (CRs; the concentration of an element in a plant in relation to the concentration in the soil), soils from the experiments were also analysed to calculate extractable concentrations of Cs and Sr. To test if cultivars have consistently low Cs and Sr concentration ratios, 17 hybrid ryegrass cultivars were sampled from both sites again in summer 2013 and spring and summer 2014. Tall fescue cultivars had lower Cs and Sr CRs than the other species. Three of the selected 17 hybrid ryegrass cultivars had consistently low Cs CRs, two had consistently low Sr CRs and one had consistently low Cs and Sr CRs. Cultivar substitution could reduce Cs CRs by up to 14-fold and Sr CRs by 4-fold in hybrid ryegrass. The identification of species and cultivars with consistently low CRs suggests that species or cultivar substitution could be an effective remediation strategy for contaminated areas. PMID:28459808

  11. Forage grasses with lower uptake of caesium and strontium could provide 'safer' crops for radiologically contaminated areas.

    Directory of Open Access Journals (Sweden)

    Beth Penrose

    Full Text Available Substitution of a species or cultivar with higher uptake of an element by one with lower uptake has been proposed as a remediation strategy following accidental releases of radioactivity. However, despite the importance of pasture systems for radiological dose, species/cultivar substitution has not been thoroughly investigated for forage grasses. 397 cultivars from four forage grass species; hybrid ryegrass (Lolium perenne L. x Lolium multiflorum Lam., perennial ryegrass (Lolium perenne L., Italian ryegrass (Lolium multiflorum Lam. and tall fescue (Festuca arundinacea Shreb.; were sampled from 19 field-based breeding experiments in Aberystwyth and Edinburgh (UK in spring 2013 and analysed for caesium (Cs and strontium (Sr concentrations. In order to calculate concentration ratios (CRs; the concentration of an element in a plant in relation to the concentration in the soil, soils from the experiments were also analysed to calculate extractable concentrations of Cs and Sr. To test if cultivars have consistently low Cs and Sr concentration ratios, 17 hybrid ryegrass cultivars were sampled from both sites again in summer 2013 and spring and summer 2014. Tall fescue cultivars had lower Cs and Sr CRs than the other species. Three of the selected 17 hybrid ryegrass cultivars had consistently low Cs CRs, two had consistently low Sr CRs and one had consistently low Cs and Sr CRs. Cultivar substitution could reduce Cs CRs by up to 14-fold and Sr CRs by 4-fold in hybrid ryegrass. The identification of species and cultivars with consistently low CRs suggests that species or cultivar substitution could be an effective remediation strategy for contaminated areas.

  12. A new approach to predicting environmental transfer of radionuclides to wildlife: A demonstration for freshwater fish and caesium

    Energy Technology Data Exchange (ETDEWEB)

    Beresford, N.A., E-mail: nab@ceh.ac.uk [NERC Centre for Ecology and Hydrology, Lancaster Environment Centre, Library Av. Bailrigg, Lancaster LA1 4AP (United Kingdom); Yankovich, T.L. [Saskatchewan Research Council, Environment and Forestry, 125, 15 Innovation Blvd., Saskatoon, SK S7N 2X8 (Canada); Wood, M.D. [School of Environment and Life Sciences, Room 323, Peel Building, University of Salford, Manchester, M5 4WT (United Kingdom); Fesenko, S. [International Atomic Energy Agency, 1400 Vienna (Austria); Andersson, P. [Strålsäkerhetsnymdigheten, Swedish Radiation Safety Authority, SE-171 16 Stockholm (Sweden); Muikku, M. [STUK, P.O. Box 14, 00881 Helsinki (Finland); Willey, N.J. [Centre for Research in Biosciences, University of the West of England, Coldharbour Lane, Frenchay, Bristol BS16 1QY (United Kingdom)

    2013-10-01

    The application of the concentration ratio (CR) to predict radionuclide activity concentrations in wildlife from those in soil or water has become the widely accepted approach for environmental assessments. Recently both the ICRP and IAEA have produced compilations of CR values for application in environmental assessment. However, the CR approach has many limitations, most notably, that the transfer of most radionuclides is largely determined by site-specific factors (e.g. water or soil chemistry). Furthermore, there are few, if any, CR values for many radionuclide-organism combinations. In this paper, we propose an alternative approach and, as an example, demonstrate and test this for caesium and freshwater fish. Using a Residual Maximum Likelihood (REML) mixed-model regression we analysed a dataset comprising 597 entries for 53 freshwater fish species from 67 sites. The REML analysis generated a mean value for each species on a common scale after REML adjustment taking account of the effect of the inter-site variation. Using an independent dataset, we subsequently test the hypothesis that the REML model outputs can be used to predict radionuclide, in this case radiocaesium, activity concentrations in unknown species from the results of a species which has been sampled at a specific site. The outputs of the REML analysis accurately predicted {sup 137}Cs activity concentrations in different species of fish from 27 Finnish lakes; these data had not been used in our initial analyses. We recommend that this alternative approach be further investigated for other radionuclides and ecosystems. - Highlights: • An alternative approach to estimating radionuclide transfer to wildlife is presented. • Analysed a dataset comprising 53 freshwater fish species collected from 67 sites. • Residual Maximum Likelihood mixed model regression is used. • Model output takes account of the effect of inter-site variation. • Successfully predicted {sup 137}Cs concentrations in

  13. Re-dissolution of caesium and plutonium from Irish Sea sediments: a comparison between different modelling approaches

    International Nuclear Information System (INIS)

    Iosjpe, M.A.; Perianez, R.B.

    2004-01-01

    Recently, there has been experimental evidence of re-dissolution of plutonium and caesium taking place from contaminated Irish Sea sediments. Thus, sediments are behaving as a long-term source of waste radionuclides to the water column. The objective of this work consists of studying such re-dissolution process by means of mathematical modelling. In particular, two models with different conceptual and numerical approaches will be used. The first is a box model for long-term dispersion from Sellafield to the Arctic marine environment in which water fluxes between boxes are obtained from basic oceanographic information. Water sediment interactions of radionuclides are described through sedimentation and remobilization processes on the basis of the sediment equilibrium distribution coefficient. The second model is a high resolution 3D model in which advective transport is obtained from the calculated current fields. Thus, tidal mixing is explicitly computed. Exchanges of radionuclides between the liquid and solid phases are described in terms of kinetic transfer coefficients. As a consequence, the model has a general applicability and can be used in situations out from equilibrium conditions. Both models have been used to simulate the dispersion of instantaneous releases from Sellafield and to simulate the process of re-dissolution of radionuclides from contaminated sediments. Results from both models are comparable, being differences in activity levels in water and sediments smaller than should be expected from the different modelling approaches. Some general conclusions on the applicability of each modelling approach and on how they can be combined to improve predictions can also be extracted from this work. (author)

  14. Spectral anomalies of the effect of light-induced drift of caesium atoms caused by the velocity dependence of transport collision frequencies

    Energy Technology Data Exchange (ETDEWEB)

    Parkhomenko, A I [Institute of Automation and Electrometry, Siberian Branch of the Russian Academy of Sciences, Novosibirsk (Russian Federation); Shalagin, A M [Novosibirsk State University, Novosibirsk (Russian Federation)

    2014-10-31

    The spectral features of the light-induced drift (LID) velocity of caesium atoms in inert buffer gases are studied theoretically. A strong temperature dependence of the spectral LID line shape of Cs atoms in Ar or Kr atmosphere in the vicinity of T ∼ 1000 K is predicted. It is shown that the anomalous LID of Cs atoms in binary buffer mixtures of two different inert gases can be observed at virtually any (including ambient) temperature, depending on the content of the components in these mixtures. The results obtained make it possible to precisely test the interatomic interaction potentials in the experiments on the anomalous LID. (quantum optics)

  15. Caesium absorption by barley - influence of its retention by the soil - competitive action of potassium; Absorption du cesium par l'orge - influence de sa retention dans le sol - action competitive du potassium

    Energy Technology Data Exchange (ETDEWEB)

    Ferron-Trosseau, F. [Commissariat a l' Energie Atomique, Fontenay-aux-Roses (France). Centre d' Etudes Nucleaires

    1964-06-01

    We have studied, in various culture media, how the absorption of caesium by barley varies with its concentration, and how this absorption can be in competition with a similar alkali cation-potassium. We have also considered the caesium distribution in the ground in particular radio-active caesium, between the soil and solution, as a function of the amount of caesium. From our work it is clear that barley behaves very differently according to whether the caesium is in a nutritive solution or is in the soil: for a nutritive solution, the fraction of caesium (radioactive and stable) absorbed by barley remains practically constant in the presence of increasing amounts (relatively small) of stable caesium; in soil, the fraction of the radio-active caesium absorbed increases as the stable caesium content (fairly low) of the soil increases, in relationship with a rapidly decreasing selectivity of the soil for Cs{sup +}. The difference between these results is thus explained by the very pronounced selectivity of the illitic soil studied for Cs{sup +}, as long as the proportion of Cs remains low, about as low as that of most natural soils. Furthermore, the K{sup +} ion is in competition with the Cs{sup +} ion, for absorption by barley in a culture medium in a nutritive solution or in soil, only when the potassium concentrations are relatively low, of the order of the nutritive maximum. This shows that the addition of potassium to a medium already rich in this element does not reduce the absorption of caesium by barley. The choice of experimental conditions close to natural conditions (nutritive media strong in calcium) and the examination of the distribution of radioactive caesium between the soil, the soil solution and the plant in the presence of very low doses of stable caesium make these results interesting from the 'atomic health' point of view; it should be expected that a definite contamination risk exists for plants cultivated on synthetic media and for

  16. Caesium absorption by barley - influence of its retention by the soil - competitive action of potassium; Absorption du cesium par l'orge - influence de sa retention dans le sol - action competitive du potassium

    Energy Technology Data Exchange (ETDEWEB)

    Ferron-Trosseau, F [Commissariat a l' Energie Atomique, Fontenay-aux-Roses (France). Centre d' Etudes Nucleaires

    1964-06-01

    We have studied, in various culture media, how the absorption of caesium by barley varies with its concentration, and how this absorption can be in competition with a similar alkali cation-potassium. We have also considered the caesium distribution in the ground in particular radio-active caesium, between the soil and solution, as a function of the amount of caesium. From our work it is clear that barley behaves very differently according to whether the caesium is in a nutritive solution or is in the soil: for a nutritive solution, the fraction of caesium (radioactive and stable) absorbed by barley remains practically constant in the presence of increasing amounts (relatively small) of stable caesium; in soil, the fraction of the radio-active caesium absorbed increases as the stable caesium content (fairly low) of the soil increases, in relationship with a rapidly decreasing selectivity of the soil for Cs{sup +}. The difference between these results is thus explained by the very pronounced selectivity of the illitic soil studied for Cs{sup +}, as long as the proportion of Cs remains low, about as low as that of most natural soils. Furthermore, the K{sup +} ion is in competition with the Cs{sup +} ion, for absorption by barley in a culture medium in a nutritive solution or in soil, only when the potassium concentrations are relatively low, of the order of the nutritive maximum. This shows that the addition of potassium to a medium already rich in this element does not reduce the absorption of caesium by barley. The choice of experimental conditions close to natural conditions (nutritive media strong in calcium) and the examination of the distribution of radioactive caesium between the soil, the soil solution and the plant in the presence of very low doses of stable caesium make these results interesting from the 'atomic health' point of view; it should be expected that a definite contamination risk exists for plants cultivated on synthetic media and for plants such

  17. Computer modelling of the chemical speciation of caesium, uranium(VI) and neptunium(V) in human duodenal fluids under fasting conditions

    International Nuclear Information System (INIS)

    Jones, P.W.; Taylor, D.M.; Webb, L.M.; Williams, D.R.

    2002-01-01

    A model simulating the human duodenal contents under physiologically realistic, fasting conditions was developed using the joint expert speciation system (JESS) computer program and database and used to investigate the chemical speciation of caesium, uranium(VI) and neptunium(V). Over the pH range 5.0-9.0, and the concentration range 5x10 -15 -5x10 -5 mol dm -3 , caesium was predicted to occur predominantly as the absorbable free monovalent cation Cs + (∼95%) with species such as CsHPO 4 - and CsCl representing the remainder. The presence or absence of sulphate at 2.1x10 -3 mol dm -3 did not influence the predicted speciation. Uranium was predicted to be present entirely as a soluble, highly charged species, both in the absence and in the presence of sulphate. Between pH 5.0 and ∼6.5 the UO 2 H 2 (PO 4 ) 2 2- predominated, above this pH carbonate species, either UO 2 (CO 3 ) 4 6- or, possibly, UO 2 (CO 3 ) 5 8- . At pH 8.0, and in the presence of sulphate, neptunium(V) was predicted to exist solely as the tetrasulphate species, whilst in the absence of sulphate, an array of negatively charged soluble carbonate species predominated. Studies over the pH range 5.0-9.0 predicted the formation of a spectrum of negatively charged carbonate and phosphate species, ∼40% of the total neptunium was predicted to be present as the electrically net-neutral species NpO 2 HCO 3 at pH6.0, ∼20% at pH 7.0, ∼10% at pH 7.5 and ∼1% at pH 8.0. The observed speciation patterns of uranium and neptunium did not change over the concentration range 5x10 -15 -5x10 -5 mol dm -3 and no solid species were predicted to occur under the conditions simulated. Whether the predicted electrically net-neutral neptunium species or the uranium pentacarbonate species do actually occur under true physiological conditions remains to be established. The observed speciation patterns for caesium and uranium are consistent with the observed absorption of these elements by humans; however, the

  18. Sheepmeat (caesium levels)

    International Nuclear Information System (INIS)

    Rifkind, M.; Robertson, J.H.; Corrie, J.

    1986-01-01

    The Secretary of State for Scotland (Mr Malcolm Rifkind) said in the House of Commons, that as a result of tests on young lambs in Scotland, in which 5 readings of over 1,000bk/kg for cesium 134 and 137 were found, he has made an order prohibiting the movement and slaughter of sheep in Dumfries, Galloway, Arran and Easter Ross, for 21 days. Monitoring would continue. He was cross-questioned about health hazards to the public of eating lamb already slaughtered but assured M.P's that there was no risk. Compensation for affected farmers was also discussed. (U.K.)

  19. Adapting the Caesium-137 technique to document soil redistribution rates associated with traditional cultivation practices in Haiti.

    Science.gov (United States)

    Velasco, H; Astorga, R Torres; Joseph, D; Antoine, J S; Mabit, L; Toloza, A; Dercon, G; Walling, Des E

    2018-03-01

    Large-scale deforestation, intensive land use and unfavourable rainfall conditions are responsible for significant continuous degradation of the Haitian uplands. To develop soil conservation strategies, simple and cost-effective methods are needed to assess rates of soil loss from farmland in Haiti. The fallout radionuclide caesium-137 ( 137 Cs) provides one such means of documenting medium-term soil redistribution rates. In this contribution, the authors report the first use in Haiti of 137 Cs measurements to document soil redistribution rates and the associated pattern of erosion/sedimentation rates along typical hillslopes within a traditional upland Haitian farming area. The local 137 Cs reference inventory, measured at an adjacent undisturbed flat area, was 670 Bq m -2 (SD = 100 Bq m -2 , CV = 15%, n = 7). Within the study area, where cultivation commenced in 1992 after deforestation, three representative downslope transects were sampled. These were characterized by 137 Cs inventories ranging from 190 to 2200 Bq m -2 . Although, the study area was cultivated by the local farmers, the 137 Cs depth distributions obtained from the area differed markedly from those expected from a cultivated area. They showed little evidence of tillage mixing within the upper part of the soil or, more particularly, of the near-uniform activities normally associated with the plough layer or cultivation horizon. They were very similar to that found at the reference site and were characterized by high 137 Cs activities at the surface and much lower activities at greater depths. This situation is thought to reflect the traditional manual tillage practices which cause limited disturbance and mixing of the upper part of the soil. It precluded the use of the conversion models normally used to estimate soil redistribution rates from 137 Cs measurements on cultivated soils and the Diffusion and Migration conversion model frequently used for uncultivated soils was modified for

  20. Structural study of caesium-based britholites Sr7La2Cs(PO4)5(SiO4)F2

    International Nuclear Information System (INIS)

    Boughzala, K.; Gmati, N.; Bouzouita, K.; Ben Cherifa, A.; Gravereau, P.

    2010-01-01

    Several studies demonstrated the ability of britholites to retain radionuclides such as the caesium and actinides. Therefore, three compounds with formulas Sr 8 LaCs(PO 4 ) 6 F 2 , Sr 7 La 2 Cs(PO 4 ) 5 (SiO 4 )F 2 and Sr 2 La 7 Cs(SiO 4 ) 6 F 2 , were prepared by solid state reaction. However, it seems that only the mono-silicated composition was obtained in a pure state. In this present work, the X-ray diffraction and magnetic nuclear resonance have been used to investigate the structure for this composition. The results showed that in fact this phase was not pure, but it was mixed with a secondary phase, SrLaCs(PO 4 ) 2 . The refinement by the Rietveld method allowed also to precise the distribution of La 3+ and Cs + ions between the two cationic sites of the apatite. (authors)

  1. The behaviour of transport from the fission products caesium and strontium in coated particles for high temperature reactors under irradiation conditions

    International Nuclear Information System (INIS)

    Zoller, P.

    1976-07-01

    At first survey is given about existing knowledge of the behaviour of caesium and strontium fission product transport in coated particles. In order to describe the complicated fission product transport mechanisms under irradiation conditions a suitable calculating model (SLIPPER) is taken over and modified to the special problems of an irradiation experiment. Fundamentally, the fission product transport is represented by the two contributions of diffusion and recoil, at which the diffusion is described by effective diffusion coefficients. In difference of that the possibility of a two-phase-diffusion is examined for the Cs diffusion in the fuel kernel. The model application on measuring results from irradiation experiments of KFA-Juelich and Mol-Belgien allowed the explanation from the characteristic of fission product transport in coated particles under irradiation conditions and produced effective diffusion coefficients for the fission products Cs and Sr. (orig.) [de

  2. Caesium-137 in Groups of Populations; Le Cesium 137 dans les Groupes de Population; 0426 0415 0417 0414 ; El Cesio-137 en Grupos de Poblacion

    Energy Technology Data Exchange (ETDEWEB)

    Miettinen, J. K. [Department of Radiochemistry, University of Helsinki (Finland)

    1964-11-15

    This review is a synthesis of results obtained by authors who have submitted papers on caesium-137 burdens in population groups and was prepared at the request of the scientific secretariat of this Symposium. (author) [French] Cette etude fan la synthese des resultats obtenus par des auteurs qui ont presente des memoires sur la charge corporelle de cesium 137 dans les groupes de population; elle a ete etablie a la demande du secretariat scientifique du Colloque. (author) [Spanish] El presente estudio constituye una sintesis de los resultados obtenidos por autores que han presentado memorias sobre la carga corporal de cesio-137 en distintos grupos de poblacion, y se ha preparado a peticion de la Secretaria cientifica de este Simposio. (author) [Russian] Jetot obzor predstavljaet soboj obobshhenie rezul'tatov, poluchennyh avtorami, kotorye predstavili doklady otnositel'no soderzhanija cezija-137 v gruppah populjacij, i byl podgotovlen po pros'be nauchnogo sekretariata simpoziuma. (author)

  3. Caesium uptake in mushroom. Comparison with coexisting elements and effect of ammonium ion as a competitor, by laboratory experiments using Hebeloma vinosophyllum

    International Nuclear Information System (INIS)

    Ho, Quyen Bao-Thuy; Yoshida, Satoshi; Suzuki, Akira

    2013-01-01

    An ectomycorrhizal ammonia fungus Hebeloma vinosophyllum was cultivated in the Ohta's liquid medium with Cs and different concentrations of NH 4 + . This fungus absorbed caesium and coexisting elements(K, Ca, Mg, Zn, Cu, Fe and P) with the highly transfer factors. The highest translocation from mycelium to fruit body was observed in Cs among 8 analysed elements. The uptake of Cs might have a similar pattern to those of K and P. However, the high concentration of NH 4 + might affect as the competitor to the uptake of both Cs and K, but not to the uptake of P. The addition of NH 4 + affected more the uptake of Cs than that of K. (author)

  4. Monitoring of caesium-137 in food plants and muscle from moose, red deer and wild reindeer in 2010.; Overvaaking av cesium-137 i beitevekster og kjoett av elg, hjort og villrein i 2010.

    Energy Technology Data Exchange (ETDEWEB)

    Veiberg, Vebjoern; Gaare, Eldar; Stokke, Sigbjoern; Solberg, Erling J.; Skuterud, Lavrans

    2011-07-01

    The monitoring of Cs-137 fall-out from the Chernobyl accident in 1986, started the same year. Several plants and wild reindeer in natural ecosystems in Nord-Rondane have been followed annually ever since. Four more wild reindeer ranges were included in 2001: Setesdal-Ryfylkeheiene, Hardangervidda, Nord-Ottadalen, Snoehetta and Nord-Rondane. From 2007 Forollhogna was also included. On fixed plots in Nord-Rondane and Snoehetta some of the reindeer forage plants, including both higher plants and fruticose lichens, have been sampled and analyzed annually since 1986. This was also done in 2010. In addition plants and lichens were sampled at five locations along an altitudinal gradient at Soendre Knutshoe, and at 7-8 locations along an east-west gradient from Kollaflata to Skarhoe in the Jora valley continuing along the Aursjoe to Torbudalen. All these locations were sampled annually between 1987-1990, but they have not been sampled since. In 2010 samples from red deer and moose was also collected from eight different regions located within the following counties: Oppland, Telemark, Vest-Agder, Rogaland, Sogn and Fjordane, Nord-Troendelag, Nordland and Troms. Red deer were sampled in four regions and moose in six. Both species were sampled in Oppland. In 2010 76, 49 and 61 samples were collected from wild reindeer, red deer and moose respectively. All measures of caesium levels were performed on dried samples. For the 596 samples of plants and lichen the results refer to caesium-levels in dried samples. For the meat samples, results refer to caesium-137 levels in raw meat. Due to large variation in measured levels of caesium within species and sampling area, we give median values instead of mean values.The highest caesium levels in wild reindeer were found in Snoehetta (1010 Bq/kg) and Nord-Rondane (2686 Bq/kg). The levels found in the other areas were considerably lower. The highest caesium levels in both red deer (Sel, 677 Bq/kg) and moose (Vaaga, 365 Bq/kg) were found

  5. Comments and Guidance to the Regulations and General Advice from the Swedish Radiation Protection Authority on the handling of Ashes Contaminated by Caesium-137; Kommentarer och vaegledning till foereskrifter och allmaenna raad om hantering av aska som aer kontaminerad med cesium-137

    Energy Technology Data Exchange (ETDEWEB)

    Moere, Hans; Hubbard, Lynn Marie

    2005-05-01

    The Swedish Radiation Protection Authority has issued Regulations and General Advice on the handling of Ashes Contaminated by Caesium-137, in SSI FS 2005:1. In this document the separate paragraphs are explained to facilitate their practical implementation.

  6. The Assessment of Radioactive Caesium in Man; Determination du Radiocesium chez l'Homme; 041e 041f 0420 0415 0414 ; Determinacion del Cesio Radiactivo en el Hombre

    Energy Technology Data Exchange (ETDEWEB)

    Rundo, J.; Taylor, B. T. [United Kingdom Atomic Energy Research Establishment, Harwell, Berks. (United Kingdom)

    1964-11-15

    The content of radiocaesium (caesium-134, caesium-137) in the human body may be estimated either by body radioactivity measurement or by excretion analyses. This paper discusses some of the difficulties of these two methods. The use of a whole-body counter poses a problem of calibration; this may be done by means of a solution- filled phantom or (for caesium-137) by the administration of caesium-132. Comparison of these two methods shows that use of an average calibration factor derived from a phantom gives results which are not in error by more than {+-} 12% for subjects weighing between 50 kg and 100 kg. In the estimation of radiocaesium contents by excretion analysis there are several sources of uncertainty. The biological half-life varies among individuals from about 50 d to 150 d or more, with a mean of about 110 d. Use of the mean value to calculate a body content from the daily excretion rate can therefore give a result in error by a factor of as much as two. Experimental evidence will be presented to show that in many cases an estimate of the biological half-life can be obtained from the ratio of the urinary to faecal excretions. The effect of the short-lived component in the retention of caesium on the estimation of a body content is much more important. Use of the correct urinary excretion rate based on the long-lived component can overestimate the content by as much as eight times when applied to the caesium content of urine voided in the first 24 h after intake. The over-estimate from the contents of individual 24-h urine samples does not fall below 50% until about one week after intake. Day-to-day variations introduce errors of no more than {+-} 30%. There are marked diurnal variations in the urinary excretion rate of caesium; multiplication by three of the caesium content of an 8-h urine sample voided during the day to obtain the 24-h output over-estimates the excretion rate but by not more than about 30%. An alternative estimate of the body content

  7. Radioactive caesium contamination due to Fukushima Daiichi Nuclear Power Plants accident in Osaka city. Evaluation of accumulation and decontamination of radioactive materials via reverse logistics function of a city

    International Nuclear Information System (INIS)

    Nishio, Takayuki; Kitano, Masaaki; Sakai, Mamoru; Takakura, Akito; Katahira, Kenshi; Nishitani, Takashi

    2015-01-01

    We surveyed background level of radioactive contamination in city area of Osaka before combusting the wide area disposal of disastrous debris at a municipal waste incineration plant of Osaka city. The debris was caused by Tohoku district great earthquake disaster and suspected to be contaminated with radionuclides released from the Fukushima Daiichi Nuclear Power Plants. We also investigated radioactivity in incineration ash of municipal waste incineration plants and of sewage treatment plants, as well as in water clarifier sludge of potable water treatment plants, and evaluated the accumulation and cleansing of radioactive materials via the reverse logistic function of the city. Radioactive caesium deposited in Osaka city area was estimated to be approximately 4.3 GBq from the concentrations observed in the monthly fallout, whereas that collected as municipal wastes and sewage was estimated to be approximately 0.9 GBq a year in 2011. Even two years after the accident, "1"3"4Cs, which is the evidence of the Fukushima Daiichi Nuclear Power Plant accident, had been detected in the municipal wastes at a level comparable to the activities found just after the accident, however, the radioactive caesium concentration in fallout measured in the Osaka city area had decreased below a detection limit after May 2012. Introduction of materials contaminated with radioactive caesium from outside the city area was suspected because the observed contamination level was inexplicable by that of observed in the environmental wastes such as pruned branches which are contaminated by with the fallout in city area of Osaka. (author)

  8. Effects of fluvial processes in different order river valleys on redistribution and storage of particle-bound radioactive caesium-137 in area of significant Chernobyl fallout and impact on linked rivers with lower contamination levels

    Science.gov (United States)

    Belyaev, Vladimir; Golosov, Valentin; Shamshurina, Evgeniya; Ivanov, Maxim; Ivanova, Nadezhda; Bezukhov, Dmitry; Onda, Yuichi; Wakiyama, Yoshifumi; Evrard, Olivier

    2015-04-01

    Detailed investigations of the post-fallout fate of radionuclide contamination represent an important task in terms of environmental quality assessment. In addition, particle-bound radionuclides such as the most widespread anthropogenic isotope caesium-137 can be used as tracers for quantitative assessment of different sediment redistribution processes. In landscapes of humid plains with agriculture-dominated land use the post-fallout redistribution of caesium-137 is primarily associated with fluvial activity of various scales in cascade systems starting from soil erosion on cultivated hillslopes through gully and small dry valley network into different order perennial streams and rivers. Our investigations in the so-called Plavsk hotspot (area of very high Chernobyl caesium-137 contamination within the Plava River basin, Tula Region, Central European Russia) has been continuing for more than 15 years by now, while the time passed since the Chernobyl disaster and associated radioactive fallout (1986) is almost 29 years. Detailed information on the fluvial sediment and associated caesium-137 redistribution has been obtained for case study sites of different size from individual cultivated slopes and small catchments of different size (2-180 km2) to the entire Plava River basin scale (1856 km2). It has been shown that most of the contaminated sediment over the time passed since the fallout has remained stored within the small dry valleys of the 1-4 Hortonian order and local reservoirs (>70%), while only about 5% reached the 5-6 order valleys (main tributaries of the Plava River) and storage of the Plava floodplain itself represents as low as 0.3% of the basin-scale total sediment production from eroded cultivated hillslopes. Nevertheless, it has been shown that contaminated sediment yield from the Plava River basin exerts significant influence on less polluted downstream-linked river system. Recent progress of the investigations involved sampling of 7 detailed depth

  9. Precision mass measurements for studies of nucleosynthesis via the rapid neutron-capture process. Penning-trap mass measurements of neutron-rich cadmium and caesium isotopes

    Energy Technology Data Exchange (ETDEWEB)

    Atanasov, Dinko

    2016-07-06

    Although the theory for the rapid neutron-capture process (r-process) was developed more than 55 years ago, the astrophysical site is still under a debate. Theoretical studies predict that the r-process path proceeds through very neutron-rich nuclei with very asymmetric proton-to-neutron ratios. Knowledge about the properties of neutron-rich isotopes found in similar regions of the nuclear chart and furthermore suitable for r-process studies is still little or even not existing. The basic nuclear properties such as binding energies, half-lives, neutron-induced or neutron-capture reaction cross-sections, play an important role in theoretical simulations and can vary or even drastically alternate results of these studies. Therefore, a considerable effort was put forward to access neutron-rich isotopes at radioactive ion-beam facilities like ISOLDE at CERN. The goal of this PhD thesis is to describe the experimental work done for the precision mass measurements of neutron-rich cadmium ({sup 129-131}Cd) and caesium ({sup 132,146-148}Cs) isotopes. Measurements were done at the on-line radioactive ion-beam facility ISOLDE by using the four-trap mass spectrometer ISOLTRAP. The cadmium isotopes are key nuclides for the synthesis of stable isotopes around the mass peak A = 130 in the Solar System abundance.

  10. Microhydration of caesium compounds: Cs, CsOH, CsI and Cs₂I₂ complexes with one to three H₂O molecules of nuclear safety interest.

    Science.gov (United States)

    Sudolská, Mária; Cantrel, Laurent; Cernušák, Ivan

    2014-04-01

    Structure and thermodynamic properties (standard enthalpies of formation and Gibbs free energies) of hydrated caesium species of nuclear safety interest, Cs, CsOH, CsI and its dimer Cs₂I₂, with one up to three water molecules, are calculated to assess their possible existence in severe accident occurring to a pressurized water reactor. The calculations were performed using the coupled cluster theory including single, double and non-iterative triple substitutions (CCSD(T)) in conjunction with the basis sets (ANO-RCC) developed for scalar relativistic calculations. The second-order spin-free Douglas-Kroll-Hess Hamiltonian was used to account for the scalar relativistic effects. Thermodynamic properties obtained by these correlated ab initio calculations (entropies and thermal capacities at constant pressure as a function of temperature) are used in nuclear accident simulations using ASTEC/SOPHAEROS software. Interaction energies, standard enthalpies and Gibbs free energies of successive water molecules addition determine the ordering of the complexes. CsOH forms the most hydrated stable complexes followed by CsI, Cs₂I₂, and Cs. CsOH still exists in steam atmosphere even at quite high temperature, up to around 1100 K.

  11. Precision mass measurements for studies of nucleosynthesis via the rapid neutron-capture process Penning-trap mass measurements of neutron-rich cadmium and caesium isotopes

    CERN Document Server

    AUTHOR|(CDS)2085660; Litvinov, Yuri A.; Kreim, Susanne

    Although the theory for the rapid neutron-capture process (r-process) was developed more than 55 years ago, the astrophysical site is still under a debate. Theoretical studies predict that the r-process path proceeds through very neutron-rich nuclei with very asymmetric proton- to-neutron ratios. Knowledge about the properties of neutron-rich isotopes found in similar regions of the nuclear chart and furthermore suitable for r-process studies is still little or even not existing. The basic nuclear properties such as binding energies, half-lives, neutron-induced or neutron-capture reaction cross-sections, play an important role in theoretical simulations and can vary or even drastically alternate results of these studies. Therefore, a considerable effort was put forward to access neutron-rich isotopes at radioactive ion-beam facilities like ISOLDE at CERN. The goal of this PhD thesis is to describe the experimental work done for the precision mass measurements of neutron-rich cadmium (129−131 Cd) and caesium...

  12. Sensitivity of the modelled deposition of Caesium-137 from the Fukushima Dai-ichi nuclear power plant to the wet deposition parameterisation in NAME

    International Nuclear Information System (INIS)

    Leadbetter, Susan J.; Hort, Matthew C.; Jones, Andrew R.; Webster, Helen N.; Draxler, Roland R.

    2015-01-01

    This paper describes an investigation into the impact of different meteorological data sets and different wet scavenging coefficients on the model predictions of radionuclide deposits following the accident at the Fukushima Dai-ichi nuclear power plant in March 2011. Three separate operational meteorological data sets, the UK Met Office global meteorology, the ECMWF global meteorology and the Japan Meteorological Agency (JMA) mesoscale meteorology as well as radar rainfall analyses from JMA were all used as inputs to the UK Met Office's dispersion model NAME (the Numerical Atmospheric-dispersion Modelling Environment). The model predictions of Caesium-137 deposits based on these meteorological models all showed good agreement with observations of deposits made in eastern Japan with correlation coefficients ranging from 0.44 to 0.80. Unexpectedly the NAME run using radar rainfall data had a lower correlation coefficient (R = 0.66), when compared to observations, than the run using the JMA mesoscale model rainfall (R = 0.76) or the run using ECMWF met data (R = 0.80). Additionally the impact of modifying the wet scavenging coefficients used in the parameterisation of wet deposition was investigated. The results showed that modifying the scavenging parameters had a similar impact to modifying the driving meteorology on the rank calculated from comparing the modelled and observed deposition

  13. Progress report on a filed study of soil-to-plant transfer of radioactive caesium, strontium and zinc in tropical Northern Australia

    International Nuclear Information System (INIS)

    Twining, J.; McOrist, G.; Zawadzki, A.; Shotton, P.

    2000-09-01

    This report covers: background, study location, design and rationale, farming practice and application, climate monitoring, summaries of the results of chemical analyses, gamma spectrometry and other analyses performed on plants and soil samples and calculation of transfer factors. Comparison with data from the literature, and a brief discussion of the results and implications for the on-going study are also presented. A detailed evaluation of the results has not been performed at this stage as the study is in progress.The main general observations to date are as follows. Transfer factors for caesium (Cs) and strontium (Sr) are not substantially different from the expected values based on the earlier studies mainly within temperate climates. In contrast, the values for zinc (Zn) are more than an order of magnitude greater than anticipated. Most of the radioactivity added to the soils has been retained in the top 5 cm of both soils. There has been a general decline in decay-corrected radioactivity in soils but also an indication of increased heterogeneity in surface distribution. Additional sampling will be undertaken to address this issue

  14. Combining caesium-137 measurements and suspended sediment load data to investigate the sediment response of a small catchment in southern Italy

    Directory of Open Access Journals (Sweden)

    P. Porto

    2015-03-01

    Full Text Available A long-term measurement programme was operated in southern Italy during the 1960s and 1970s, to provide information on the suspended sediment yields from the main river basins. Information obtained for the rivers of Calabria suggests that suspended sediment yields in this area are relatively low. However, there is evidence that the intensity of land degradation within the upstream catchments is substantially higher than suggested by the values of specific sediment yield and there is a need to explore the relationship between on-site soil loss and downstream sediment yield more closely. Monitoring time-integrated erosion rates over large areas has traditionally required extensive long-term measurement programmes employing experimental plots. The fallout radionuclide caesium-137 (137Cs offers an alternative means of documenting medium-term rates of soil loss. This paper describes the use of 137Cs measurements and the available sediment load data to explore the links between soil erosion, sediment redistribution and storage, and sediment output for a medium-scale (41.3 km2 catchment in Calabria. Data available from a sediment load monitoring programme undertaken at the catchment outlet during 1962–1977 have been used to estimate the longer-term catchment sediment yield. This estimate has been combined with information provided by the 137Cs measurements, to establish a medium-term sediment budget for the catchment. The results provided by the 137Cs measurements indicate that the catchment is subject to much higher rates of soil loss and land degradation than suggested by its specific sediment yield. These findings are consistent with the results obtained for other catchments in Calabria for which both 137Cs derived erosion rates and measured sediment yields are available.

  15. The high affinity K+ transporter AtHAK5 plays a physiological role in planta at very low K+ concentrations and provides a caesium uptake pathway in Arabidopsis.

    Science.gov (United States)

    Qi, Zhi; Hampton, Corrina R; Shin, Ryoung; Barkla, Bronwyn J; White, Philip J; Schachtman, Daniel P

    2008-01-01

    Caesium (Cs(+)) is a potentially toxic mineral element that is released into the environment and taken up by plants. Although Cs(+) is chemically similar to potassium (K(+)), and much is known about K(+) transport mechanisms, it is not clear through which K(+) transport mechanisms Cs(+) is taken up by plant roots. In this study, the role of AtHAK5 in high affinity K(+) and Cs(+) uptake was characterized. It is demonstrated that AtHAK5 is localized to the plasma membrane under conditions of K(+) deprivation, when it is expressed. Growth analysis showed that AtHAK5 plays a role during severe K(+) deprivation. Under K(+)-deficient conditions in the presence of Cs(+), Arabidopsis seedlings lacking AtHAK5 had increased inhibition of root growth and lower Cs(+) accumulation, and significantly higher leaf chlorophyll concentrations than wild type. These data indicate that, in addition to transporting K(+) in planta, AtHAK5 also transports Cs(+). Further experiments showed that AtHAK5 mediated Cs(+) uptake into yeast cells and that, although the K(+) deficiency-induced expression of AtHAK5 was inhibited by low concentrations of NH(4)(+) in planta, Cs(+) uptake by yeast was stimulated by low concentrations of NH(4)(+). Interestingly, the growth of the Arabidopsis atakt1-1 mutant was more sensitive to Cs(+) than the wild type. This may be explained, in part, by increased expression of AtHAK5 in the atakt1-1 mutant. It is concluded that AtHAK5 is a root plasma membrane uptake mechanism for K(+) and Cs(+) under conditions of low K(+) availability.

  16. Tracing sediment sources in the Williams River catchment using caesium-137 and heavy metals: towards an assessment of the relative importance of surface erosion and gully erosion

    International Nuclear Information System (INIS)

    Krause, A.K.; Kalma, J.D.; Loughran, R.J.

    1999-01-01

    Recent sediment sourcing in the 1175km 2 Williams River catchment near Newcastle, NSW, has involved the use of caesium-137 ( 137 Cs) and heavy metals to identify zones of erosion and estimate erosion rates. Sediment sources to the Williams River include sheet erosion from forested and grazed lands, stream channels (especially banks), gullies and roads. The fallout environmental radioisotope 137 Cs was used to assess the erosion status of five vegetated slopes using soil sampling along transects. The net loss or gain of 137 Cs at each sampling point was compared with the 137 Cs level at a reference site at the slope crest. Net soil loss at each point was calculated from an Australian regression model relating net soil loss from runoff-erosion plots to 137 Cs deficit in soils (n=34; r=0.84). Net soil gain was calculated using the regression model in reverse mode. A weighted net soil loss (or gain) was then calculated for each slope transect. Results showed low net soil loss, ranging from zero to 0.64 t ha -1 yr 1 , suggesting that slopes were not major contributors of sediment to the Williams River. A small sub-catchment south of Wirragulla Hill, typical of the lower Williams region, was selected for more detailed tracing of sediment sources. The catchment contains gullies, sheet-erosion exposed sub-soil, grassland and one unsealed road. Heavy metals and 137 Cs have been used to fingerprint the sources, and these measurements will be compared with suspended sediment collected from drainage water in the creek. Only preliminary results have been obtained for this component of the study. The paper will assess these two approaches for the identification of sediment sources and discuss practical applications in water resources management

  17. Reduction of {sup 137}caesium contamination in wild boars by supplementing offered food with ammonium-iron-hexa-cyanoferrate; Reduktion der {sup 137}Caesium-Aktivitaet in Wildschweinen durch Zusatz von Ammonium-Eisen-Hexacyanoferrat (''Berliner Blau'') zum Kirrfutter

    Energy Technology Data Exchange (ETDEWEB)

    Morfeld, P. [Evonik Industries AG, Essen (Germany). Inst. fuer Epidemiologie und Risikobewertung in der Arbeitswelt (IERA); Koeln Univ. (Germany). Inst. und Poliklinik fuer Arbeitsmedizin, Umweltmedizin und Praeventionsforschung; Reddemann, J.; Schungel, P. [Landesjagdverband Bayern e.V., Feldkirchen (Germany); Kienzle, E. [Muenchen Univ., Oberschleissheim (Germany). Lehrstuhl fuer Tierernaehrung und Diaetetik

    2014-06-15

    This replication study investigated whether the {sup 137}caesium ({sup 137}Cs) contamination of wild boars could be relevantly reduced under field conditions by adding ammonium-iron-hexa-cyanoferrate (AFCF; Prussian blue) to the food. In 285 wild boars that had been shot in six Bavarian hunting territories during the season (November until May) between 01 November 2010 and 10 December 2011 {sup 137}Cs contamination was analysed. Thirty-five animals originated from two hunting territories in which offered food had been supplemented with 1250 mg AFCF per kilogram food. The control animals showed a mean {sup 137}Cs contamination of 522 Bq/kg lean skeletal muscle meat. Direct (univariable) comparisons of the two experimental territories with the four control territories yielded a mean reduction in {sup 137}Cs contamination due to Prussian bluefeeding by -211 Bq/kg (p < 0.001). Multivariable mo dels that took potential confounders into account (age, weight, sex, hunting date, territory) estimated the effect to be -344 Bq/kg (p < 0.05). This replication study confirmed the finding of Kienzle et al. (12) who described a statistically significant reduction in {sup 137}Cs contamination by -380 Bq/kg due to the feeding of Prussian blue in other territories. [German] Gegenstand und Ziel: Diese Replikationsstudie pruefte, ob unter Feldbedingungen die Kontamination von Wildschweinen mit {sup 137}Caesium ({sup 137}Cs) durch Zugabe vn Ammonium-Eisen-Hexacyanoferrat (AFCF, ''Berliner Blau'') zum ausgelegten Futter relevant verringert werden kann. Material und Methoden: Bei 285 Wildschweinen, die zwischen dem 01.11.2010 und dem 10.12.2011 waehrend der Jagdsaison (November bis Mai) in sechs bayerischen Jagdrevieren erlegt worden waren, erfolgte eine Analyse der {sup 137}Cs-Aktivitaet. Von diesen Tieren stammten 35 aus zwei Revieren, in denen das ausgelegte Futter mit 1250 mg AFCF/kg Futter supplementiert worden war. Ergebnisse: Die Kontrolltiere wiesen eine

  18. Treatment of solutions of fission products - Separation of caesium-137; Traitement des solutions de produits de fission - Separation du cesium-137; Obrabotka rastvorov produktov deleniya - Razdelenie tseziya-137; Tratamiento de soluciones de productos de fision - Separacion del cesio-137

    Energy Technology Data Exchange (ETDEWEB)

    Stiennon-Bovy, R [Centre d' Etude de l' Energie Nucleaire, Mol (Belgium); Gvion, R [Commission Israelienne de l' Energie Atomique, Tel-Aviv (Israel)

    1962-01-15

    For the industrial recovery of caesium-137 from solutions of fission products, the authors utilized the analytical method for determination of caesium by dipicrylamine, adapting it to use on an industrial scale and to the high level of the activities encountered. The process recommended makes it possible both to isolate caesium as a chloride and to recover the precipitation reagent, in one and the same operation. A basic method is suggested. The authors studied the effect of radiation on dipicrylamine and its compounds, this effect proving to be practically nil for solid compounds and negligible for their solutions. The entrainment of caesium by ammonia ion was also studied. The advantages of the proposed process are : high decontamination of the caesium, simple operation and free recycling fo the reagent, high yield for caesium recovery and for dipicrylamine, considerable concentration of caesium activity, operation at room temperature and possibility of continuous operation. By this process caesium can be recovered before certain fission products are eliminated. (author) [French] Pour la recuperation industrielle du cesium-137 des solutions de produits de fission, les auteurs ont adapte le procede analytique de dosage du cesium par la dipicrylamine a l'echelle industrielle et au niveau eleve des activites traitees. Le procede preconise permet en une seule operation d'isoler le cesium sous forme de chlorure et de recuperer aisement le reactif de precipitation; un schema de principe est propose. Les auteurs ont etudie l'effet des radiations sur la dipicrylamine et ses composes; cet effet s'avere pratiquement nul pour les composes solides et negligeable pour leurs solutions. L'entrainement du cesium par l'ion ammoniaque est etudie. Les avantages du procede propose sont la decontamination elevee du cesium, la simplicite du mode operatoire avec recyclage aise du reactif, le rendement eleve pour la recuperation du cesium et pour la dipicrylamine, une concentration

  19. Measurement of Caesium-137 in the Normal Person; Dosage du Cesium 137 chez un Sujet Normal; 0418 0417 041c 0414 ; Determinacion Cuantitativa del Cesio-137 en el Individuo Normal

    Energy Technology Data Exchange (ETDEWEB)

    Huycke, E. J.; Oberhausen, E. [United States Army Medical Research Unit, Europe, Landstuhl/Pfalz, Federal Republic of Germany (Germany)

    1964-11-15

    During the period June 1959 to October 1963 the Landstuhl whole-body counter has measured the caesium-137 content of more than 15 000 normal persons. The monthly averages of these measurements indicate a steady increase In the caesium-137 content since June 1962. This increase has become more rapid during the period June 1963 to October 1963. A further evaluation of the monthly averages since June 1962 indicates a mean biologic half-life of caesium-137 of 140 d for persons older than 22 yr. A comparison of the mean caesium-137 content of persons between 8 and 17 yr of age with those older than 22 appears to indicate that the biologic half-life of caesium-137 is shorter in the younger people. This is in agreement with earlier data from this counter concerning measurements of caesium-137 content between June 1959 and December 1960: these data showed a lower caesium-137 content in children than in adults. Another evaluation of recent data from this unit concerns the standard deviation (sigma) of the caesium-137 content in a large population. From this population the sigma of measured caesium/g body potassium values is 33%. This is more than twice the sigma of the body potassium content of this same population. By comparing a group of persons who have undergone several repeat assays over an extended period of time with the monthly means of the total population measured, it has been found that the large sigma of caesium-137 content cannot be caused solely by the varying diets of the population measured. (author) [French] Au cours de la periode allant de juin 1959 a octobre 1963, l'anthropogammametre de Landstuhl a ete utilise pour mesurer la charge corporelle de cesium 137 chez plus de 15 000 sujets normaux. D'apres les moyennes mensuelles de ces mesures, la charge corporelle de cesium 137 a augmente constamment depuis juin 1962. Cette augmentation s'est acceleree au cours de la periode allant de juin 1963 a octobre 1963. Une analyse plus poussee des moyennes mensuelles

  20. The application of Caesium-137 and Plutonium-239+240 measurements to investigate floodplain deposition in a semi-arid, low-fallout environment

    Science.gov (United States)

    Amos, K. J.; Croke, J. C.; Timmers, H.; Owens, P. N.

    2009-04-01

    Floodplains comprise geomorphologically important sources and sinks for sediments and associated pollutants, yet the sedimentology of large dryland floodplains is not well understood. Processes occurring on such floodplains are often difficult to observe, and techniques used to investigate smaller perennial floodplains are often not practical in these environments. This study assesses the utility of Cs-137 inventory and depth-profile techniques for determining relative amounts of floodplain sedimentation in the Fitzroy River, north-eastern Australia; a 143 000 km2 semi-arid river system. Caesium-137 inventories were calculated for floodplain and reference location bulk soil cores collected from four sites. Depth profiles of Cs-137 concentration from each floodplain site and a reference location were recorded. The areal density of Cs-137 at reference locations ranged from 13-978 Bq m-2 (0-1367 Bq m-2 at the 95% confidence interval), and the mean value ± 2(standard error of the mean) was 436±264 Bq m-2, similar to published data from other southern hemisphere locations. Floodplain inventories ranged from 68-1142 Bq m-2 (0-1692 Bq m-2 at the 95% confidence interval), essentially falling within the range of reference inventory values, thus preventing calculation of erosion or deposition. Depth-profiles of Cs-137 concentration indicate erosion at one site and over 66 cm of deposition at another since 1954. Analysis of 239+240Pu concentrations in a depositional core substantiated the interpretation made from Cs-137 data, and depict a more tightly constrained peak in concentration. Average annual deposition rates range from 0-15 mm. The similarity between floodplain and reference bulk inventories does not necessarily indicate a lack of erosion or deposition, due to low Cs-137 fallout in the region and associated high measurement uncertainties, and a likely influence of gully and bank eroded sediments with no or limited adsorbed Cs-137. In this low-fallout environment

  1. Long term reduction of Caesium and Strontium transfer factors from soil in foodstuff and dynamics of internal doses for a russian population after the Chernobyl accident

    International Nuclear Information System (INIS)

    Shutov, V.N.; Bruk, J.Ja.; Travnikova, I.G.; Balonov, M.I.

    2002-01-01

    The model of the formation of the internal doses for the population living on the territory contaminated after the Chernobyl accident is described. Model parameters were obtained on the base of natural measurements results implemented in the different terms after the accident. The data on the caesium radionuclides content in the bodies of the inhabitants measurements were priority for the internal exposure dose estimation. In the case of the absence of such information, the results of the radionuclides content in the food products analysis or the data on the soil types prevailing in the areas of settlements, were used for the calculations. The data were obtained during 1986-2001 as a result of monitoring of contaminated areas in Russia that considerably differ in their soil and climate conditions, the levels of 1 37C s and 9 0S r surface activity on soil and types of countermeasures applied. A summary of effective half-lives (T 1/2 ) of 1 37C s and 9 0S r aggregated transfer factors (Tag) from soil into agricultural and natural products observed after the Chernobyl fallout is given. The short term decrease of 1 37C s Tag from soil into milk and beef during two months after fallout were observed - T 1/2 varied from 13 d to 36 d in depend on the part of dry and wet fallout. The studies between autumn 1986 and 1991 suggest a decrease in the 1 37C s Tag with T 1/2 /2 =1-2 years. From 5-6 years after deposition onwards T 1/2 /2 of 1 37 Cs and 9 0S r Tag's in the range of 8 to 21 years were observed. Effective half-lives of 1 37C s Tag's for foods from semi-natural ecosystems (mushrooms, berries, game, fish) are longer (up to tens years). On at least for some natural products the decrease seems to be only to radioactive decay. Comparison of the data on the dynamics of 1 37C s content in agricultural and natural food products indicates that the contribution of the latter in the internal dose of population grows with each year after fallout, and can reach in the remote

  2. Transport behavior of radioactive caesium from forests contaminated by the Fukushima Dai-ichi nuclear power plant accident through river water system

    Energy Technology Data Exchange (ETDEWEB)

    Iijima, K.; Funaki, H.; Ohyama, T.; Niizato, T.; Sato, H.; Yui, M. [Japan Atomic Energy Agency (Japan)

    2014-07-01

    Japan Atomic Energy Agency (JAEA) has carried out 'the project on the Long-term Assessment of Transport of Radioactive Contaminant in the Environment of Fukushima (F-TRACE project)' since the end of 2012. Radioactive caesium (Cs) has been distributed by the fallout by the Fukushima Dai-ichi Nuclear Power Plant (1F-NPP) accident, and forests in mountain areas have large amount of inventory of radioactive Cs and cover relatively large part of contaminated area of Fukushima. In this project, the transport behavior of radioactive Cs from the forests to biosphere and sea is evaluated by computer simulation based on the results of field observation and laboratory experiments. The results are used to predict evolution of effective dose of the residents in the affected area due to the transport, specify the dominant pathway of Cs, and propose effective methodology to constrain the transport along the pathway. This study reports the specific transport behavior of Cs observed in the basins of five rivers by means of the field investigation and laboratory experiments during the first year of the project. Radioactive Cs located at the crown was considered to be transported to the soil surface by litter fall, stem flow and canopy drip in the Japanese cedar tree forests. Even after two years since the accident, more than 90% of radioactive Cs was still been remained within 5 cm depth from the top of the soil, indicating that the distribution coefficient of radioactive Cs onto the specific minerals such as clay was significantly high. In the river, relatively higher dose rate was observed at the flood channel where fine-grained soil particles were trapped by growing vegetation, while low dose rate was observed beside the river channel where coarse sand or gravel accumulated. The results suggested that fine-grained soil particles containing minerals adsorbing large amount of radioactive Cs were transported in high water level and trapped by the vegetation. In the dam

  3. Xenon-133 and caesium-137 releases into the atmosphere from the Fukushima Dai-ichi nuclear power plant: determination of the source term, atmospheric dispersion, and deposition

    Science.gov (United States)

    Stohl, A.; Seibert, P.; Wotawa, G.; Arnold, D.; Burkhart, J. F.; Eckhardt, S.; Tapia, C.; Vargas, A.; Yasunari, T. J.

    2012-04-01

    This presentation will show the results of a paper currently under review in ACPD and some additional new results, including more data and with an independent box modeling approach to support some of the findings of the ACPD paper. On 11 March 2011, an earthquake occurred about 130 km off the Pacific coast of Japan's main island Honshu, followed by a large tsunami. The resulting loss of electric power at the Fukushima Dai-ichi nuclear power plant (FD-NPP) developed into a disaster causing massive release of radioactivity into the atmosphere. In this study, we determine the emissions of two isotopes, the noble gas xenon-133 (133Xe) and the aerosol-bound caesium-137 (137Cs), which have very different release characteristics as well as behavior in the atmosphere. To determine radionuclide emissions as a function of height and time until 20 April, we made a first guess of release rates based on fuel inventories and documented accident events at the site. This first guess was subsequently improved by inverse modeling, which combined the first guess with the results of an atmospheric transport model, FLEXPART, and measurement data from several dozen stations in Japan, North America and other regions. We used both atmospheric activity concentration measurements as well as, for 137Cs, measurements of bulk deposition. Regarding 133Xe, we find a total release of 16.7 (uncertainty range 13.4-20.0) EBq, which is the largest radioactive noble gas release in history not associated with nuclear bomb testing. There is strong evidence that the first strong 133Xe release started early, before active venting was performed. The entire noble gas inventory of reactor units 1-3 was set free into the atmosphere between 11 and 15 March 2011. For 137Cs, the inversion results give a total emission of 35.8 (23.3-50.1) PBq, or about 42% of the estimated Chernobyl emission. Our results indicate that 137Cs emissions peaked on 14-15 March but were generally high from 12 until 19 March, when they

  4. Xenon-133 and caesium-137 releases into the atmosphere from the Fukushima Dai-ichi nuclear power plant. Determination of the source term, atmospheric dispersion, and deposition

    International Nuclear Information System (INIS)

    Stohl, A.; Burkhart, J.F.; Eckhardt, S.; Seibert, P.; Arnold, D.; Technical Univ. of Catalonia, Barcelona; Tapia, C.; Vargas, A.; Yasunari, T.J.

    2012-01-01

    On 11 March 2011, an earthquake occurred about 130 km off the Pacific coast of Japan's main island Honshu, followed by a large tsunami. The resulting loss of electric power at the Fukushima Dai-ichi nuclear power plant developed into a disaster causing massive release of radioactivity into the atmosphere. In this study, we determine the emissions into the atmosphere of two isotopes, the noble gas xenon-133 ("1"3"3Xe) and the aerosol-bound caesium-137 ("1"3"7Cs), which have very different release characteristics as well as behavior in the atmosphere. To determine radionuclide emissions as a function of height and time until 20 April, we made a first guess of release rates based on fuel inventories and documented accident events at the site. This first guess was subsequently improved by inverse modeling, which combined it with the results of an atmospheric transport model, FLEXPART, and measurement data from several dozen stations in Japan, North America and other regions. We used both atmospheric activity concentration measurements as well as, for "1"3"7Cs, measurements of bulk deposition. Regarding "1"3"3Xe, we find a total release of 15.3 (uncertainty range 12.2-18.3) EBq, which is more than twice as high as the total release from Chernobyl and likely the largest radioactive noble gas release in history. The entire noble gas inventory of reactor units 1-3 was set free into the atmosphere between 11 and 15 March 2011. In fact, our release estimate is higher than the entire estimated "1"3"3Xe inventory of the Fukushima Dai-ichi nuclear power plant, which we explain with the decay of iodine-133 (half-life of 20.8 h) into "1"3"3Xe. There is strong evidence that the "1"3"3Xe release started before the first active venting was made, possibly indicating structural damage to reactor components and/or leaks due to overpressure which would have allowed early release of noble gases. For "1"3"7Cs, the inversion results give a total emission of 36.6 (20.1-53.1) PBq, or about

  5. Xenon-133 and caesium-137 releases into the atmosphere from the Fukushima Dai-ichi nuclear power plant: determination of the source term, atmospheric dispersion, and deposition

    Directory of Open Access Journals (Sweden)

    A. Stohl

    2012-03-01

    Full Text Available On 11 March 2011, an earthquake occurred about 130 km off the Pacific coast of Japan's main island Honshu, followed by a large tsunami. The resulting loss of electric power at the Fukushima Dai-ichi nuclear power plant developed into a disaster causing massive release of radioactivity into the atmosphere. In this study, we determine the emissions into the atmosphere of two isotopes, the noble gas xenon-133 (133Xe and the aerosol-bound caesium-137 (137Cs, which have very different release characteristics as well as behavior in the atmosphere. To determine radionuclide emissions as a function of height and time until 20 April, we made a first guess of release rates based on fuel inventories and documented accident events at the site. This first guess was subsequently improved by inverse modeling, which combined it with the results of an atmospheric transport model, FLEXPART, and measurement data from several dozen stations in Japan, North America and other regions. We used both atmospheric activity concentration measurements as well as, for 137Cs, measurements of bulk deposition. Regarding 133Xe, we find a total release of 15.3 (uncertainty range 12.2–18.3 EBq, which is more than twice as high as the total release from Chernobyl and likely the largest radioactive noble gas release in history. The entire noble gas inventory of reactor units 1–3 was set free into the atmosphere between 11 and 15 March 2011. In fact, our release estimate is higher than the entire estimated 133Xe inventory of the Fukushima Dai-ichi nuclear power plant, which we explain with the decay of iodine-133 (half-life of 20.8 h into 133Xe. There is strong evidence that the 133Xe release started before the first active venting was made, possibly indicating structural damage to reactor components and/or leaks due to overpressure which would have allowed early release of noble gases. For 137

  6. Xenon-133 and caesium-137 releases into the atmosphere from the Fukushima Dai-ichi nuclear power plant. Determination of the source term, atmospheric dispersion, and deposition

    Energy Technology Data Exchange (ETDEWEB)

    Stohl, A.; Burkhart, J.F.; Eckhardt, S. [NILU - Norwegian Institute for Air Research, Kjeller (Norway); Seibert, P. [Univ. of Natural Resources and Life Sciences, Vienna (Austria). Inst. of Meteorology; Wotawa, G. [Central Institute for Meteorology and Geodynamics, Vienna (Austria); Arnold, D. [Univ. of Natural Resources and Life Sciences, Vienna (Austria). Inst. of Meteorology; Technical Univ. of Catalonia, Barcelona (Spain). Inst. of Energy Technologies; Tapia, C. [Technical Univ. of Catalonia, Barcelona (Spain). Dept. of Physics and Nucelar Engineering; Vargas, A. [Technical Univ. of Catalonia, Barcelona (Spain). Inst. of Energy Technologies; Yasunari, T.J. [Univs. Space Research Association, Columbia, MD (United States). Goddard Earth Sciences and Technology and Research

    2012-07-01

    On 11 March 2011, an earthquake occurred about 130 km off the Pacific coast of Japan's main island Honshu, followed by a large tsunami. The resulting loss of electric power at the Fukushima Dai-ichi nuclear power plant developed into a disaster causing massive release of radioactivity into the atmosphere. In this study, we determine the emissions into the atmosphere of two isotopes, the noble gas xenon-133 ({sup 133}Xe) and the aerosol-bound caesium-137 ({sup 137}Cs), which have very different release characteristics as well as behavior in the atmosphere. To determine radionuclide emissions as a function of height and time until 20 April, we made a first guess of release rates based on fuel inventories and documented accident events at the site. This first guess was subsequently improved by inverse modeling, which combined it with the results of an atmospheric transport model, FLEXPART, and measurement data from several dozen stations in Japan, North America and other regions. We used both atmospheric activity concentration measurements as well as, for {sup 137}Cs, measurements of bulk deposition. Regarding {sup 133}Xe, we find a total release of 15.3 (uncertainty range 12.2-18.3) EBq, which is more than twice as high as the total release from Chernobyl and likely the largest radioactive noble gas release in history. The entire noble gas inventory of reactor units 1-3 was set free into the atmosphere between 11 and 15 March 2011. In fact, our release estimate is higher than the entire estimated {sup 133}Xe inventory of the Fukushima Dai-ichi nuclear power plant, which we explain with the decay of iodine-133 (half-life of 20.8 h) into {sup 133}Xe. There is strong evidence that the {sup 133}Xe release started before the first active venting was made, possibly indicating structural damage to reactor components and/or leaks due to overpressure which would have allowed early release of noble gases. For {sup 137}Cs, the inversion results give a total emission of 36

  7. In Vivo Measurements of Caesium-137 with a Human Body Counter; Dosage du Cesium 137 In Vivo au Moyen d'un Anthropogammametre; 0418 0417 041c 0414 ; Medidas de Cesio-137 In Vivo con un Antropogammametro

    Energy Technology Data Exchange (ETDEWEB)

    Melandri, C. [C.N.E.N., Divisione di Biologia e Protezione Sanitaria, Bologna (Italy); Rimondi, O. [Istituto di Fisica Dell' Universita di Bologna (Italy)

    1964-11-15

    Data are given of the first measurements of human body radioactivity made in Italy with the whole-body counter built by the authors in 1962. The counter shielding is made of iron bricks 16 cm thick. Measurements inside are 270 cm x 200 cm x 200 cm. The detectors are a 9 in x 4 in Nal (Tl) crystal and three 30 cm x 20 cm x 17 cm plastic scintillators which can be used separately, in parallel, or in anticoincidence and in coincidence with the crystal. The counter has been used for determining the behaviour of the caesium-137 body content from fall-out in the whole population and for estimating the caesium-137 retention in a subject accidentally contaminated. The first measurements of caesium-137 body content from fall-out were taken on 13 subjects in December 1962 and continued regularly at three-month intervals. A gradual increase was noted in the average caesium-137 content of the population throughout the whole of 1963 up to the value of 124 pc/g of potassium in September. In a case of accidental contamination from caesium-137 (about two years before the counter was built) measurements were made in order to determine both the effective half-life of the long-term component and the initial intake of the radioelement. (author) [French] Le memoire donne des renseignements sur les premiers dosages de l'activite du corps humain qui ont ete faits en Italie au moyen de l'anthropogammametre construit par les auteurs en 1962. La protection est en briques de fer de 16cmd'eDaisseur: ses dimensions interieures sont de 270 x 200 x 200 cm. L'appareil comporte comme detecteurs un cristal de Nal (Tl) de 22, 5 x 10 cm et trois scintillateurs en matiere plastique de 30 x 20 x 17 cm qui peuvent etre utilises separement, en parallele, ou en anticoincidence et en coincidence avec le cristal. Les auteurs ont employe l'appareil pour determiner comment varie la charge corporelle de cesium 137 due aux retombees dans l'ensemble de la population, et pour estimer la retention de cesium 137

  8. A ''missing'' caesium member in the family of A{sub 3}Al{sub 2}P{sub 3}O{sub 12} aluminophosphates

    Energy Technology Data Exchange (ETDEWEB)

    Shvanskaya, Larisa [Moscow State Univ. (Russian Federation). Dept. of Crystallography; National Univ. of Science and Technology, Moscow (Russian Federation).; Yakubovich, Olga [Moscow State Univ. (Russian Federation). Dept. of Crystallography

    2017-07-01

    A new caesium aluminophosphate, Cs{sub 3}Al{sub 2}P{sub 3}O{sub 12}, has been synthesized by spontaneous crystallization from the melt and structurally characterized. The compound crystallizes in the orthorhombic space group Pnma, with a=9.7675(2) Aa, b=17.7537(3) Aa, c=8.1063(2) Aa, V=1405.71(2) Aa{sup 3}, and Z=4. Its crystal structure is based on an open interrupted framework built by alternating AlO{sub 4} and PO{sub 4} tetrahedra with Cs ions occupying the channels. The Cs{sub 3}Al{sub 2}P{sub 3}O{sub 12} framework topology resembles the previously known 4.8.12-net, which has been reported in the [C{sub 4}N{sub 3}H{sub 16}][Al{sub 2}P{sub 3}O{sub 12}] phase prepared by solvothermal synthesis in the presence of diethylenetriamine (DETA). The crystal chemical relationships between the K, Rb, Cs, Tl, [NH{sub 4}] and [C{sub 4}N{sub 3}H{sub 16}]-members of the A{sub 3}Al{sub 2}P{sub 3}O{sub 12} family of compounds are discussed.

  9. Results of several years experiments on the absorption of radioactive strontium and caesium by cultivated plants (1962); Compte rendu d'experiences de plusieurs annees sur l'absorption du strontium et du cesium radioactifs par des plantes cultivees (1962)

    Energy Technology Data Exchange (ETDEWEB)

    Michon, M [Commissariat a l' Energie Atomique, Dept. de Protection Sanitaire, Fontenay-aux-Roses (France). Centre d' Etudes Nucleaires; Benard, M; Flanzy, M [Station Centrale de Technologie des Produits Vegetaux, 11 - Narbonne (France); Fioramonti, M; Marty, M [Station Agronomique de Toulouse, 31 (France); Barbier, M; Le Blaye, M; Brossard, M [Societe Centrale d' Agronomie, 78 - Versailles (France)

    1962-07-01

    This report follows on to the report number CEA 1860 and uses results obtained in 1960 to give more precise details concerning the data presented in the preceding report. First results obtained on the vine are given. The Sr absorption coefficient has varied very little from one year to the next and that of caesium has slightly diminished. The values obtained suggest that the concentrations of {sup 90}Sr and {sup 137}Cs in irrigation water should not exceed 1/5 of the maximum permissible concentration in drinking water. (authors) [French] Ce rapport fait suite au rapport CEA 1860 et precise grace aux resultats acquis en 1960 les donnees exprimees dans le precedent rapport. Il y est fait mention des premiers resultats obtenus pour la vigne. Le coefficient d'absorption du Sr a peu varie d'une annee sur l'autre et celui du cesium legerement diminue. Les valeurs obtenues permettent de penser qu'il serait souhaitable que la concentration en {sup 90}Sr et en {sup 137}Cs dans l'eau d'irrigation ne depasse pas le 1/5 de la concentration maxima admissible pour l'eau de boisson. (auteurs)

  10. Strontium and caesium transport in unsaturated soil from Chernobyl Pilot Site under steady flow conditions; Transfert de radioelements en zone non saturee. Etude experimentale et modelisation appliquees au Site Pilote de Tchernobyl

    Energy Technology Data Exchange (ETDEWEB)

    Szenknect, St

    2003-10-15

    This work is devoted to the quantification and the identification of the predominant processes involved in strontium and caesium transport in unsaturated soil from Chernobyl Pilot Site under steady flow conditions. The transport and fate of radionuclides in the subsurface is affected by various physical and chemical processes including advective and diffusive transport as well as chemical and biological transformations. Laboratory experiments and the use of a multiple tracer approach allow to isolate the contributions of each elementary process and to control the physico-chemical conditions in the system. To be more representative of the field conditions, we decided to perform column miscible displacement experiments. We perform batch and flow-through reactor experiments to characterize the radionuclides sorption mechanisms. Miscible displacement experiments within homogeneous columns and modeling allow to characterize the hydrodynamic properties of the soil and to describe the radionuclides behaviour under dynamic conditions at different water contents. We show that the water content of porous media affect the transport behaviour of inert and strongly sorbing radionuclides. Our results demonstrate that a parametrized transport model that was calibrated under completely saturated conditions was not able to describe the advective-dispersive transport of reactive solutes under unsaturated steady state conditions. Under our experimental conditions, there is no effect of a decrease of the mean water content on the sorption model parameters, but the transport parameters are modified. We established for the studied soil the relation between hydrodynamic dispersion and water content and the relation between pore water velocity and water content. (author)

  11. The Effect of Chlorothiazide on Caesium-137 Excretion in Human Subjects; Effet de la Chiorothiazide sur l'Elimination du Cesium 137 chez l'Homme; 0412 041b 0414 ; Influencia de la Ciorotiazida sobre la Excrecion de Cesio en el Hombre

    Energy Technology Data Exchange (ETDEWEB)

    Harrison, Joan; McNeill, K. G. [Departments of Medicine and Physics, University of Toronto, ON (Canada)

    1964-11-15

    The present study was carried out to determine factors that influence caesium metabolism in normal human subjects with particular interest in finding a therapeutic regimen for reducing the body burden of caesium. Since caesium and potassium are chemically similar, and are both localized in the intracellular compartment of the body, principally in muscle, it seemed possible that chlorothiazide, which has a marked potassium diuretic effect, might also increase caesium excretion. Four normal subjects were given a single dose of 0.1 {mu}c of caesium-137 by mouth. Two subjects were given chlorothiazide 2.0 g/d for a total of three consecutive days starting 1 h after the caesium intake. The chlorothiazide dose was repeated at two weeks. The other two subjects were used as controls. The body burden of caesium-137 was measured by a whole-body counter at intervals up to 320 d. Daily urine collections were made for three control days and 20 d following caesium intake. The samples were analysed for electrolytes and caesium activity. Although chlorothiazide increased K excretion to 1. 5 times the control values, it had no significant effect on caesium excretion or in reducing the body burden of caesium. In all subjects a small fraction of caesium (10-20%) was excreted rapidly with a biological half-life (T),) of less than 1 d. The remainder was excreted at a constant rate with T{sub b} of 90 to 155 d. More than 70% of the caesium eliminated from the body per day was excreted by the kidney. T{sub b} of K was also calculated by the formula T{sub bK} = Total body K/Urine K x 0,693 x 0,8 assuming 80% of the total potassium excreted is by kidney. Tb of K was 35 to 42 d. The discrimination ratio T{sub bCs}/T{sub bK} was 2.1 to 3.8. These results demonstrate that caesium and potassium are not utilized interchangeably. Caesium is retained preferentially over potassium and changes in potassium turnover have no effect on caesium turnover. Studies are being carried out at the present

  12. Cobalt-60 and Caesium-137 Gamma Sources; Sources de rayonnement gamma au cobalt-60 et au cesium-137; Gamma-istochniki iz kobal'ta-605 i tseziya-137; Fuentes gamma de cobalto-60 y de cesio-137

    Energy Technology Data Exchange (ETDEWEB)

    Kulish, E E; Fradkin, G M [Academy of Sciences of the USSR, Moscow, Union of Soviet Socialits Republics (Russian Federation)

    1960-07-15

    The paper gives the main technical characteristics of gamma sources produced in the USSR using cobalt-60 and caesium-137 and discusses some of the problems of their production technology. The paper contains information on the radiation spectra of Co{sup 60} and Cs{sup 137} and of the source material from which they are prepared. Data are given on the dependence of the activity of cobalt sources upon the intensity of the neutron beam and the geometrical size of the sample. The yield of caesium by uranium fission is also analyzed. The problem of hermetic sealing of the sources is discussed and a complete nomenclature of all the sources manufactured in the USSR are listed, their size and activity also being indicated. In conclusion a comparison of Co{sup 60} and Cs{sup 137} sources is made. (author) [French] Cette communication expose les caracteristiques techniques fondamentales des sources de rayonnement gamma a base de cobalt-60 et de cesium-137 pro- duites en URSS; on y examine egalement certaines questions relatives a la technologie de leur production. La communication contient des donnees sur la nature du rayonnement des isotopes {sup 60}Co et {sup 137}Cs, ainsi que sur celle des matieres brutes utilisees pour leur preparation. On donne les resultats obtenus lors de l'etude de la variation de l'activite des sources au cobalt en fonction de la valeur du flux de neutrons et des dimensions geometriques de l'echantillon, ainsi que les resultats relatifs a la valeur du rendement en isotopes de cesium lors de la fission des noyaux d'uranium. On etudie ensuite les procedes pour assurer l'hermeticite de ces sources. Suit une nomenclature complete des sources produites en URSS, comportant des indications sur leurs dimensions geometriques et sur les valeurs de leur activite. Enfin, il est procede a une comparaison des sources au {sup 60}Co et au {sup 137}Cs. (author) [Spanish] En este informe se describen las principales caracteristicas tecnicas de las fuentes gamma de

  13. Energy balance of the cathode connection and calculation of the yield of caesium diodes; Bilan des energies dans la connexion de cathode et calcul du rendement dans les diodes a cesium

    Energy Technology Data Exchange (ETDEWEB)

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

    1964-07-01

    The cathode connection is one of the critical elements in the calculation of the yield of caesium diodes. In particular a study is made of the balance of the losses due to the Joule effect, to radiation and to thermal conduction as a function of the shape and the nature of the cathode connection. The internal voltage drop of the diode is obtained from the expression for the total Joule losses of the metallic conductors. The length of the cathode connection is calculated as a function of the losses and the yield is optimized as a function of the relationship existing between the cathodic losses due to thermal conduction and the Joule losses in the connection. The calculations lead to hyper-elliptic integrals which can only be manipulated by series development. The results obtained are approximate. (author) [French] Dans le calcul du rendement des diodes a cesium, la connexion de cathode est l'un des elements critiques. On etudie specialement le bilan des pertes par effet joule, rayonnement et conduction thermique, en fonction de la forme et de la nature de la connexion de cathode. On obtient la chute de tension interne de la diode a partir de l'expression des pertes joules totales dans les conducteurs metalliques. La longueur de la connexion de cathode est calculee en fonction des pertes et l'on optimise le rendement en fonction du rapport qui existe entre les pertes par conduction thermique de la cathode et les pertes joules dans la connexion. Les calculs conduisent a des integrales hyperelliptiques dont la manipulation n'est possible que par des developpements en serie. Les resultats cherches sont approximatifs. (auteur)

  14. European inter-comparison of Monte Carlo codes users for the uncertainty calculation of the kerma in air beside a caesium-137 source; Intercomparaison europeenne d'utilisateurs de codes monte carlo pour le calcul d'incertitudes sur le kerma dans l'air aupres d'une source de cesium-137

    Energy Technology Data Exchange (ETDEWEB)

    De Carlan, L.; Bordy, J.M.; Gouriou, J. [CEA Saclay, LIST, Laboratoire National Henri Becquerel, Laboratoire de Metrologie de la Dose 91 - Gif-sur-Yvette (France)

    2010-07-01

    Within the frame of the CONRAD European project (Coordination Network for Radiation Dosimetry), and more precisely within a work group paying attention to uncertainty assessment in computational dosimetry and aiming at comparing different approaches, the authors report the simulation of an irradiator containing a caesium 137 source to calculate the kerma in air as well as its uncertainty due to different parameters. They present the problem geometry, recall the studied issues (kerma uncertainty, influence of capsule source, influence of the collimator, influence of the air volume surrounding the source). They indicate the codes which have been used (MNCP, Fluka, Penelope, etc.) and discuss the obtained results for the first issue

  15. Assessment of contemporary erosion/sedimentation rates trend within a small well-cultivated catchments using caesium-137 as a chronomarker (on the example of the Republic of Tatarstan, Russia)

    Science.gov (United States)

    Sharifullin, Aidar; Gusarov, Artem; Gafurov, Artur; Golosov, Valentin

    2017-04-01

    extreme (storm) precipitation (>50 mm per a day). The influence of agricultural activity on the erosion and sedimentation changeability was insignificant, although some regional variation of crop rotation including an increase in the proportion of perennial grasses obviously caused the decline in soil losses during warm period of year. The similar trend of erosion/sedimentation rates due to mostly climate changes was identified for south-western sector of the East European Plain, but the more serious reduction of erosion rates is established for the Middle Volga region. Keywords: erosion, sedimentation, sediment, caesium-137, dry valley, small catchment, cultivated lands, Republic of Tatarstan, East European Plain.

  16. Uptake of radionuclides caesium and cobalt

    International Nuclear Information System (INIS)

    Lukac, P.; Foldesova, M.

    1995-01-01

    By means of chemical treatment ammonium, potassium, sodium and H-form of zeolite were prepared. The chemical modifications of zeolite were carried out with: 2M solution of NaNO 3 , NH 4 NO 3 , KNO 3 ; 0,1M solution of HCl; NaOH solution of different concentration. The method of model radioactive solution was used to find the sorption ability for cesium and cobalt every modified zeolite. The model solution were 0.05M solution of cobalt labelled by 60 Co or cesium labelled by 137 Cs. The highest sorption ability was observed for zeolite modified by NaOH. The influence of pH on uptake of cesium and cobalt by modified zeolite was searched as well. The experimental data (leaching tests, compressive strength measurement and porosity) were measured for the case the Cs and Cs from model water solution and radioactive waste water were up taken on chemically modified zeolite and were subsequently incorporated into cement casts on blast furnace cement slags basis. The leachability was tested in water, in basis solution and in acid solution. The leachability in water and basic solution was negligible, in acid solution it was less than 4% which is inside of value of applied measure method. The compressive strength, porosity and leaching experiment are hopefully and show good mechanical stability and good retention of observed radionuclides in samples exposed in leaching solutions. (J.K.)

  17. Magnetic hyperfine field at caesium in iron

    International Nuclear Information System (INIS)

    Ashworth, C.J.; Back, P.; Stone, N.J.; White, J.P.; Ohya, S.

    1990-01-01

    We report temperature dependence of nuclear orientation (NO), and the first observation of NMR/ON on Cs in iron. 132,136 Cs were implanted at room temperature into polycrystalline and single crystal iron. NO values for the (average) magnetic hyperfine field B hf (CsFe) are close to 34 T, intermediate between the value of 40.7 T found in on-line samples made at mK temperatures and the NMR/ON value of 27.8(2) T. The latter studies. The site/field distribution is briefly discussed. (orig.)

  18. Phase transitions in ternary caesium lead bromide

    Czech Academy of Sciences Publication Activity Database

    Rodová, Miroslava; Brožek, J.; Knížek, Karel; Nitsch, Karel

    2003-01-01

    Roč. 71, - (2003), s. 667-673 ISSN 1388-6150 R&D Projects: GA AV ČR IAA2010926; GA ČR GA203/02/0436 Institutional research plan: CEZ:AV0Z1010914 Keywords : DSC * high temperature X-ray diffraction * phase transitions * CsPbBr 3 * thermal expansion coefficient * TMA Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 1.094, year: 2003

  19. Potassium, rubidium and caesium in fungi

    Energy Technology Data Exchange (ETDEWEB)

    Johanson, K.J.; Nikolova, I. [Swedish Univ. of Agricultural Sciences, Uppsala (Sweden). Dept. of Forest Mycology and Pathology; Vinichuk, M. [Swedish Univ. of Agricultural Sciences, Uppsala (Sweden). Dept. of Soil Sciences

    2005-09-15

    Samples of mushrooms and soil were collected in a forest ecosystem close to Nuclear Power Plant at Forsmark, Sweden. The soil were fractionated in bulk soil, rhizosphere, soil-root interface and fungal mycelium and the concentration of K, Rb and Cs were determined. The K concentration increased from 605 mg/kg in bulk soil to 2,750 mg/kg in mycelium and 39,500 in fruitbodies of fungi. The corresponding values for Rb was 2.5 mg/kg in bulk soil and 191 mg/kg in fruitbodies of fungi. For Cs the corresponding values were 0.21 mg/kg for bulk soil and 3.9 mg/kg in fruitbodies. In fruitbodies of fungi good correlation was found between the concentration of K and Rb or of Rb and Cs, but not between K and Cs. Yoshida found similar correlation and concluded that the mechanism of Cs uptake by fungi may be different from that of K.

  20. Sorption studies of caesium by complex hexacyanoferrates

    International Nuclear Information System (INIS)

    Jacobi, D.

    1992-01-01

    A comprehensive literature review was carried out on the preparation of complex hexacyanoferrates in a granular form suitable for use in a packed column. The preparation of sodium nickel hexacyanoferrate using a freeze-thaw method was studied in detail and a method developed to produce a consistent and reproducible granular product. The equilibrium and sorption kinetics were studied using batch and column tests, and the process modelled to predict performance under various conditions. (author)

  1. Xenon plasma with caesium as additive

    International Nuclear Information System (INIS)

    Stojilkovic, S.M.; Novakovic, N.V.; Zivkovic, L.M.

    1986-01-01

    The concentration dependence of xenon plasma with cesium as additive in the temperature range of 2000 K to 20,000 K is analyzed. Plasma is considered as weakly nonideal in complete local thermodynamic equilibrium and the interaction between plasma and vessel walls is not taken into account. The values of some of the parameters for nonideality of plasma with 1% of cesium (γ=0.01010) and 10% of cesium (γ=0.11111) are computed, for an initial pressure in plasma of p 0 =13,000 Pa and initial temperature T 0 =1000 K. The ratio of electric conductivity of plasma computed by Lorentz's formula and electric conductivity computed by Spitzer's formula in the same temperature interval is also analyzed. (author) 5 figs., 2 tabs., 16 refs

  2. Xenon plasma with caesium as additive

    Energy Technology Data Exchange (ETDEWEB)

    Stojilkovic, S M; Novakovic, N V; Zivkovic, L M

    1986-01-01

    The concentration dependence of xenon plasma with cesium as additive in the temperature range of 2000 K to 20,000 K is analyzed. Plasma is considered as weakly nonideal in complete local thermodynamic equilibrium and the interaction between plasma and vessel walls is not taken into account. The values of some of the parameters for nonideality of plasma with 1% of cesium (..gamma..=0.01010) and 10% of cesium (..gamma..=0.11111) are computed, for an initial pressure in plasma of p/sub 0/=13,000 Pa and initial temperature T/sub 0/=1000 K. The ratio of electric conductivity of plasma computed by Lorentz's formula and electric conductivity computed by Spitzer's formula in the same temperature interval is also analyzed. (author) 5 figs., 2 tabs., 16 refs.

  3. Uptake of radionuclides caesium and cobalt

    Energy Technology Data Exchange (ETDEWEB)

    Lukac, P; Foldesova, M [Slovak Technical Univ., Bratislava (Slovakia)

    1996-12-31

    By means of chemical treatment ammonium, potassium, sodium and H-form of zeolite were prepared. The chemical modifications of zeolite were carried out with: 2M solution of NaNO{sub 3}, NH{sub 4}NO{sub 3}, KNO{sub 3}; 0,1M solution of HCl; NaOH solution of different concentration. The method of model radioactive solution was used to find the sorption ability for cesium and cobalt every modified zeolite. The model solution were 0.05M solution of cobalt labelled by {sup 60}Co or cesium labelled by {sup 137}Cs. The highest sorption ability was observed for zeolite modified by NaOH. The influence of pH on uptake of cesium and cobalt by modified zeolite was searched as well. The experimental data (leaching tests, compressive strength measurement and porosity) were measured for the case the Cs and Cs from model water solution and radioactive waste water were up taken on chemically modified zeolite and were subsequently incorporated into cement casts on blast furnace cement slags basis. The leachability was tested in water, in basis solution and in acid solution. The leachability in water and basic solution was negligible, in acid solution it was less than 4% which is inside of value of applied measure method. The compressive strength, porosity and leaching experiment are hopefully and show good mechanical stability and good retention of observed radionuclides in samples exposed in leaching solutions. (J.K.).

  4. Radioactive caesium in hunters and their families

    Energy Technology Data Exchange (ETDEWEB)

    Aagren, G; Bergman, R [Natonal Defence Research Establishment, Umeaa (Sweden); Drottz-Sjoeberg, B M [Center for Risk Research, Stockholm (Sweden); Enander, A [National Defence Research Establishment, Karlstad (Sweden); Johansson, K J [Swedish Univ. of Agricultural Sciences, Uppsala (Sweden)

    1995-12-01

    We have measured the whole-body content of radiocesium in men and women in households, where at least one member is a hunter. Hunter families live to a great extent on forest products, such as mushrooms, berries and meat from game. Measurements were performed in two areas in northern Sweden and in three areas in the middle part of Sweden with deposition levels between 7 to 80 kBq/m{sup 2}. The average whole body content of {sup 137}Cs varied between 0.3 to 1.9 kBq for women and 0.6 to 4.7 kBq for men, depending on the deposition level. Each individual in the measured group was also asked to fill in questionnaire and a food diary to provide complementary information of, e.g., food intake and other life conditions. The single dietary factor most clearly related to whole-body content in these groups is the intake of meat from moose. The best regression model with variables from the questionnaire explained 60% of the variance in the whole-body content of {sup 137}Cs in the measurement group. Some of the variables in this model were deposition level, sex, rate of intake and estimated consumption of moose meat and estimated amount of bilberries in the fridge. 6 refs, 5 figs, 14 tabs.

  5. Radioactive caesium in hunters and their families

    International Nuclear Information System (INIS)

    Aagren, G.; Bergman, R.; Drottz-Sjoeberg, B.M.; Enander, A.; Johansson, K.J.

    1995-12-01

    We have measured the whole-body content of radiocesium in men and women in households, where at least one member is a hunter. Hunter families live to a great extent on forest products, such as mushrooms, berries and meat from game. Measurements were performed in two areas in northern Sweden and in three areas in the middle part of Sweden with deposition levels between 7 to 80 kBq/m 2 . The average whole body content of 137 Cs varied between 0.3 to 1.9 kBq for women and 0.6 to 4.7 kBq for men, depending on the deposition level. Each individual in the measured group was also asked to fill in questionnaire and a food diary to provide complementary information of, e.g., food intake and other life conditions. The single dietary factor most clearly related to whole-body content in these groups is the intake of meat from moose. The best regression model with variables from the questionnaire explained 60% of the variance in the whole-body content of 137 Cs in the measurement group. Some of the variables in this model were deposition level, sex, rate of intake and estimated consumption of moose meat and estimated amount of bilberries in the fridge. 6 refs, 5 figs, 14 tabs

  6. The Body Burden of Caesium-137 in People of Southern Finland 1961-1963; Charge Corporelle de Cesium 137 chez les Habitants de la Finlande Meridionale en 1961-1963; 0421 041e 0414 ; Carga Corporal de Cesio-137 en Ciertos Grupos Demograficos del Sur de Finlandia en 1961-1963

    Energy Technology Data Exchange (ETDEWEB)

    Haesaenen, E.; Miettinen, J. K. [Department of Radiochemistry, University of Helsinki (Finland)

    1964-11-15

    In connection with the investigations of the caesium-137, body burden of Finnish Lapps several measurements of smaller groups of people living in Southern Finland were carried out. In November 1961 eleven Helsinki inhabitants, five men and six women, 15 to 54 yr. old, were counted for caesium-137 and potassium in Stockholm. None of these persons were laboratory workers, two were schoolboys. They were apparently healthy. Their diet was studied by the interview method. Ten of these people were counted again in the mobile whole-body counter of the Radiochemical Department of the University of Helsinki one year later. The average body burden of caesium-137 in men (5, average age 29) had increased from 8.4 nc in November 1961 to 18.4 nc in November 1962, in women (5, average age 34) from 2.9 nc to 8.7 nc. Potassium contents were the same within 2% (men 140 g, women, 100 g) For more detailed studies larger control groups were selected at the beginning of 1963 and counted four times, in February, May, August and October. For the group of men 25 privates of an infantry battalion (age 19, average weight 65 kg), for women 24 girl students of a household school (age 22, average weight 60 kg), were selected. In both cases the diet could be checked in detail and could be considered to be an average Finnish diet. In addition, the individual food consumption of each subject was studied by interview with the aid of weighed samples. Caesium-137 contents of both diets were determined for the time periods between the measurements. In both groups the caesium-137 content remained about constant (men, 17,5 nc; women, 11 nc) until the end of June, when the caesium-137 content of milk and meat was approximately doubled within about one week. At the end of August the body burden of caesium-137 had increased in, both groups to about 40% above the spring level in the middle of October the men's values had increased by 22%, the women's values by 14% of the August level. The determination of

  7. Results of several years experiments on the absorption of radioactive strontium and caesium by cultivated plants (1962); Compte rendu d'experiences de plusieurs annees sur l'absorption du strontium et du cesium radioactifs par des plantes cultivees (1962)

    Energy Technology Data Exchange (ETDEWEB)

    Michon, M. [Commissariat a l' Energie Atomique, Dept. de Protection Sanitaire, Fontenay-aux-Roses (France). Centre d' Etudes Nucleaires; Benard, M.; Flanzy, M. [Station Centrale de Technologie des Produits Vegetaux, 11 - Narbonne (France); Fioramonti, M.; Marty, M. [Station Agronomique de Toulouse, 31 (France); Barbier, M.; Le Blaye, M.; Brossard, M. [Societe Centrale d' Agronomie, 78 - Versailles (France)

    1962-07-01

    This report follows on to the report number CEA 1860 and uses results obtained in 1960 to give more precise details concerning the data presented in the preceding report. First results obtained on the vine are given. The Sr absorption coefficient has varied very little from one year to the next and that of caesium has slightly diminished. The values obtained suggest that the concentrations of {sup 90}Sr and {sup 137}Cs in irrigation water should not exceed 1/5 of the maximum permissible concentration in drinking water. (authors) [French] Ce rapport fait suite au rapport CEA 1860 et precise grace aux resultats acquis en 1960 les donnees exprimees dans le precedent rapport. Il y est fait mention des premiers resultats obtenus pour la vigne. Le coefficient d'absorption du Sr a peu varie d'une annee sur l'autre et celui du cesium legerement diminue. Les valeurs obtenues permettent de penser qu'il serait souhaitable que la concentration en {sup 90}Sr et en {sup 137}Cs dans l'eau d'irrigation ne depasse pas le 1/5 de la concentration maxima admissible pour l'eau de boisson. (auteurs)

  8. Assessment of the Total Body Burden of Caesium-137 in Humans by the Analysis of Blood; Determination de la Charge Corporelle de Cesium 137 chez l'Homme, par Analyse Du Sang; 041e 041f 0420 0415 0414 ; Evaluacion de la Carga Corporal Total de Cesio-137 en el Hombre por Analisis de Sangre

    Energy Technology Data Exchange (ETDEWEB)

    Yamagata, N. [Institute of Public Health, Tokyo (Japan)

    1964-11-15

    Analysis of post-mortem samples for caesium-137 has been carried on in Japan because whole-body counters are limited in number and not mobile, making the assessment of the population mean levels inconvenient. However, the collection of muscles from autopsies throughout the country is complicated and inconvenient in that a sample should be taken immediately after death. Considering that only such data as are useful for the assessment of the mean levels of caesium-137 in people are required and it is unnecessary to know individual values, the composite samples of as many individuals as possible would be enough for the analysis. For this purpose, whole blood samples were considered as the best substitute for muscles, as the blood collection system covers the whole country, including 47 licensed blood banks and about 100 hospitals. Sampling inspection is made continuously of citrated whole blood at the National Institute of Health, Tokyo, where about 500 ampoules are checked, representing more than three million donors throughout the country per year. Less than half the blood in an ampoule was consumed for inspection and the remaining half was stocked to make a composite for the determination of caesium-137 level. Blood ashes were analysed for the stable caesium content by a neutron activation method. The results afforded the relation between the concentration in the whole blood and the total body amount (1.4 mg for 70 kg man) and this relation would be identical to that for caesium-137 in an equilibrium condition. The results of blood analysis for caesium-137 obtained since June 1963 were compared with those of muscle analyses made during the same period. Good agreement was observed and the blood analysis was found to be the best means for assessing the total body burden of caesium-137 in a population. (author) [French] Au Japon, on a dose le cesium 137 d'echantillons de tissus musculaires preleves au cours d'autopsies, car il n'y a qu'un petit nombre d

  9. The Time Analysis and Frequency Distribution of Caesium-137 Fall-Out in Muscle Samples; Analyse en Fonction du Temps et Distribution des Frequences de Cesium 137 du aux Retombees de Cesium 137 Contenues dans des Echantillons de Tissu Musculaire; 0410 041d 0414 ; Analisis Temporal y Distribucion de Frecuencias del Cesio-137 Procedente de la Precipitacion Radiactiva en Muestras de Tejido Muscular

    Energy Technology Data Exchange (ETDEWEB)

    Ellett, W. H.; Brownell, G. L [Physics Research Laboratory, Massachusetts General Hospital, Boston 14, MA (United States)

    1964-11-15

    For low concentrations of artificial radioactivity in the body, detrimental effect will be most likely in that fraction of the population having many times the average amount. A meaningful evaluation of the nuclear fall-out hazard can only be made if the frequency distribution of radioactivity in the population is known. Attempts to determine the shape of the distribution curve from Kulp's data on strontium-90 concentration in children's bones have met limited success because of the small sample size and lack of strontium-90-calcium equilibrium in bone. To overcome these limitations, we have measured the caesium-137 content in approximately 900 muscle samples. These tissue samples were removed during post-mortem operations from January 1959 to August 1963. The use of caesium-137 as a fission product monitor assures that all members of the group, regardless of their age, were essentially in equilibrium with the radioactive environment at the time of death. The period of investigation coincides with the first weapon test moratorium and the resumption of large- scale testing in the fall of 1961. Average caesium-137 in the samples was relatively constant throughout 1959, decreased a factor of two during 1960, and remained relatively stable until the early summer of 1962. Since mid-1962 the average level of caesium-137 radioactivity in the sample population has steadily increased and was four times greater than the 1962 minimum by the summer of 1963. Time-independent histograms of the data have been assembled by fitting a polynomial to the raw data (sample radioactivity as a function of data of death). This pooled data has been tested statistically against normal, log-normal, and gamma frequency distributions. Results indicate that the experimental distribution is definitely not Gaussian and is best fitted by a gamma distribution. By using the empirically derived gamma distribution it is possible to predict the fraction of the population having N times the average

  10. Measurements of Caesium-137 in Finnish Lapps in 1962-1964 by a Mobile Whole-Body Counter; Dosages de Cesium 137 chez les Lapons de Finlande en 1962-1964, au Moyen d'un Anthro- Pogammametre Mobile; 0418 0417 041c 0415 0420 0414 ; Determinacion del Cesio-137 en Lapones Finlandeses, en 1962-1964, Mediante un Antropogammametro Movil

    Energy Technology Data Exchange (ETDEWEB)

    Miettinen, J. K. [Department of Radiochemistry, University of Helsinki (Finland)

    1964-11-15

    The construction, calibration and use in-field investigations of a mobile whole-body counter of the type developed by K. Liden et al, in Sweden are described. The lead shield of the present system (2 t) is located)in-the middle of a covered heavy truck. The subject is surrounded by a 4-cm thick lead coffin, the Nal(Tl) crystal (5 an-diam. x 3 in) being protected from the other directions than the coffin by 8 cm of lead. The instrumentation consists of a 512-channel analyser, printer, x, y-recorder, and stabilizer, which are kept in shock- and dust-proof boxes during transport. The truck is provided with a thermostated heating system and contains two dressing cubicles. The system was calibrated for caesium-137 by two methods: (1) By administering per os a precisely known amount (200 to 300 nc) caesium-137 to several subjects and determining the counting efficiency after 3 to 6 d. The excreted portion of caesium-137 was determined by collecting and analysing the faeces and urine. (2) By counting a plastic phantom filled with 70.kg of a solution containing 1552 nc caesium-137. The first method gave a 4,6% higher efficiency than the second. The efficiency obtained by the first method was adopted as, the true calibration. This was also checked by three inter-calibration measurements with two other whole-body counting laboratories. The agreement was good (within 1 to 4%). For potassium a preliminary calibration was made by the use of the phantom. The efficiency is 2.51 cpm/nc caesium-137 (0.60- 0.72 MeV, 20 channels), and 0.145 cpm/g K (1.38- 1.55 MeV, 30 channels). When the truck is parked on rock, the corresponding background counts with a 70 kg sugar phantom-are 77 cpm and, 58 cpm, respectively. On sandy soil the background is about half of that on rock. With this mobile counter three field investigations were carried out in Finnish Lapland. In May 1962 218 Lapps statistically representative groups from the three Finnish Lapp countries, Inari, Karesuanto and Utsjoki

  11. Distribution of radioactive caesium in the population of Northern Sweden

    International Nuclear Information System (INIS)

    Wickman, G.; Johansson, L.; Eriksson, A.

    1989-01-01

    Long term surveys of a population living in a Cs-contaminated area, by muscle-tissue measurements from medicolegal autopsies, are cheap, simple and probably as accurate as whole-body measurements. Our parallel measurements of muscle concentration versus total body per gram potassium, indicate that it is possible to find consistent conversion factors to give total body content and internal absorbed dose. The great discrepancy in average total body content found by a whole body measurement survey when compared to our autopsy material measurements, indicates that severe underestimates can result from the voluntarism associated with the whole-body measurement technique. The average annual absorbed dose 1988-1989 from internally deposited Cs-137 in studied medium and high contaminated areas (10-80 kBq/m 2 ) obtained from our material is 50 μSv. The contribution from Cs-134 should be added. The resulting absorbed dose is still small compared to the external dose from the same isotopes which is roughly ten times higher. (orig.)

  12. Radiological accidents/incidents with caesium-137 in Estonia

    International Nuclear Information System (INIS)

    Sinisoo, M.

    1998-01-01

    A report is provided of an accident and an incident involving radioactive sources in Estonia. In the 1994 occurrence, looters of a depository of radioactive waste manipulated a source containing 137 Cs and received dangerous doses of radiation. One of the persons involved died, others suffered minor burns. Another event, which occurred in early 1995, did not have a tragic outcome: an abandoned 137 Cs source was found in the vicinity of the highway linking Tallinn and Narva and was disposed of safely. Both these accidents draw attention to the potential dangers caused by the insufficient survey of the territory, radiation protection structures not yet fully operable, and the lack of equipment and know-how. The lessons to be drawn from these events are considered on the basis of the chronologies and factual data. The report contains concise descriptions of the accidents, a medical overview of the fate of the injured persons and the lessons learned from these accidents. (author)

  13. Animated molecular dynamics simulations of hydrated caesium-smectite interlayers

    Directory of Open Access Journals (Sweden)

    Sposito Garrison

    2002-09-01

    Full Text Available Computer animation of center of mass coordinates obtained from 800 ps molecular dynamics simulations of Cs-smectite hydrates (1/3 and 2/3 water monolayers provided information concerning the structure and dynamics of the interlayer region that could not be obtained through traditional simulation analysis methods. Cs+ formed inner sphere complexes with the mineral surface, and could be seen to jump from one attracting location near a layer charge site to the next, while water molecules were observed to migrate from the hydration shell of one ion to that of another. Neighboring ions maintained a partial hydration shell by sharing water molecules, such that a single water molecule hydrated two ions simultaneously for hundreds of picoseconds. Cs-montmorillonite hydrates featured the largest extent of this sharing interaction, because interlayer ions were able to inhabit positions near surface cavities as well as at their edges, close to oxygen triads. The greater positional freedom of Cs+ within the montmorillonite interlayer, a result of structural hydroxyl orientation and low tetrahedral charge, promoted the optimization of distances between cations and water molecules required for water sharing. Preference of Cs+ for locations near oxygen triads was observed within interlayer beidellite and hectorite. Water molecules also could be seen to interact directly with the mineral surface, entering its surface cavities to approach attracting charge sites and structural hydroxyls. With increasing water content, water molecules exhibited increased frequency and duration of both cavity habitation and water sharing interactions. Competition between Cs+ and water molecules for surface sites was evident. These important cooperative and competitive features of interlayer molecular behavior were uniquely revealed by animation of an otherwise highly complex simulation output.

  14. Animated molecular dynamics simulations of hydrated caesium-smectite interlayers

    Science.gov (United States)

    Sutton, Rebecca; Sposito, Garrison

    2002-01-01

    Computer animation of center of mass coordinates obtained from 800 ps molecular dynamics simulations of Cs-smectite hydrates (1/3 and 2/3 water monolayers) provided information concerning the structure and dynamics of the interlayer region that could not be obtained through traditional simulation analysis methods. Cs+ formed inner sphere complexes with the mineral surface, and could be seen to jump from one attracting location near a layer charge site to the next, while water molecules were observed to migrate from the hydration shell of one ion to that of another. Neighboring ions maintained a partial hydration shell by sharing water molecules, such that a single water molecule hydrated two ions simultaneously for hundreds of picoseconds. Cs-montmorillonite hydrates featured the largest extent of this sharing interaction, because interlayer ions were able to inhabit positions near surface cavities as well as at their edges, close to oxygen triads. The greater positional freedom of Cs+ within the montmorillonite interlayer, a result of structural hydroxyl orientation and low tetrahedral charge, promoted the optimization of distances between cations and water molecules required for water sharing. Preference of Cs+ for locations near oxygen triads was observed within interlayer beidellite and hectorite. Water molecules also could be seen to interact directly with the mineral surface, entering its surface cavities to approach attracting charge sites and structural hydroxyls. With increasing water content, water molecules exhibited increased frequency and duration of both cavity habitation and water sharing interactions. Competition between Cs+ and water molecules for surface sites was evident. These important cooperative and competitive features of interlayer molecular behavior were uniquely revealed by animation of an otherwise highly complex simulation output.

  15. Transparent caesium bromide storage-phosphors for radiation imaging

    Energy Technology Data Exchange (ETDEWEB)

    Winch, Nicola M. [School of Chemical and Physical Sciences, Victoria University of Wellington, Wellington (New Zealand); Edgar, Andrew [School of Chemical and Physical Sciences, Victoria University of Wellington, Wellington (New Zealand); MacDiarmid Institute for Advanced Materials and Nanotechnology, Victoria University of Wellington, Wellington (New Zealand)

    2012-12-15

    Semi-transparent discs of polycrystalline CsBr:Eu{sup 2+} storage phosphor for X-ray imaging have been produced using a room temperature milling/pressing technique, and have been studied using infrared, and photoluminescence spectroscopies, together with scanning electron microscopy. The pressed discs are very sensitive to water vapour, and scanning electron microscopy shows that material undergoes a complete recrystallization following exposure to humid air for a few minutes through a room temperature hydration/crystallization process. Discs prepared by a simple mixture of CsBr and EuBr{sub 2} show photostimulated luminescence (PSL) at 440 nm without further processing, and the conversion efficiency is sufficient that X-ray imaging can be demonstrated. Discs which have been prepared by first sintering at 600 C, then pressed, and finally hydrated at room temperature show very strong PSL with a conversion efficiency of {proportional_to}36 pJ mR{sup -1} mm{sup -3}. A model is proposed for the generation of the active PSL centres in CsBr by the milling/hydration process. (Copyright copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  16. Concentration of caesium isotopes in foodstuffs in Poland

    International Nuclear Information System (INIS)

    Grabowski, D.; Rubel, B.; Muszynski, W.; Kurowski, W.; Swietochowska, J.; Smagala, G.

    2000-01-01

    One of the sources of the radioactive doses obtained by people resulting from the radiological contamination of the environment, is the transfer of radionuclides to the organism via ingestion. Radioactive isotopes in foodstuffs appear as a result of nuclear activities on the globe, mainly because of nuclear explosion and, recently, after the Chernobyl accident. Since the early sixties the network of Service for Measurement of Radioactive Contamination in Poland systematically controlled all kinds of important food products. Radiochemical methods and gamma spectrometry has been used to determination the activity of radioactive isotopes. This contribution reports of the determination of 134 Cs and 137 Cs concentration in milk, meat, vegetables, fruits, cereals and 'forest products' during period 1985-1999. In 1985 the average 137 Cs level was below 1 Bq/kg (except forest products). Moreover, no regional differences were observed the whole territory of Poland. After the Chernobyl accident situation changed completely. Average activity of 137 Cs in milk was 25 Bq/l in May 1986, 20-25 Bq/kg in beef and 10-15 Bq/kg in pork (summer months). Also fruit picked up in June and July was contaminated, mainly currents. The contamination of vegetables was less important. The activity of cesium isotopes in forest mushrooms and wild game were much higher than in other tested foodstuffs. From the 1987 level of radioactive contamination was decreasing gradually. In 1999 the activity of 137 Cs of vegetables, cereals, fruit was on level as it has been in 1985 as for meat and milk it is higher. Level of radiocesium in 'forest products' is still high. The average annual effective dose from ingestion of radiocesium was on level 0.088 mSv in 1986 and 0.006 mSv in 1999. (author)

  17. Melamine phosphomolybdate - a new ion selective compound for caesium

    International Nuclear Information System (INIS)

    Mehta, B.J.; Baxi, D.R.

    1976-01-01

    Preparation of melamine phosphomolybdate is described and its composition is determined. The compound is found to be granular having much higher selectivity for Cs + than that of ammonium phosphomolybdate. (orig.) [de

  18. Honey as a bioindicator of environment contamination with caesium

    International Nuclear Information System (INIS)

    Barisic, D.; Lovrencic, I.; Orescanin, V.; Kezic, N.; Bubalo, D.; Popijac, M.; Volner, M.

    2005-01-01

    Collecting nectar and pollen, bees cover area of approximately 20 km 2 . Honey from a beehive represents a composite sample collected from several hundreds of millions of points and is probably one of the most representative random samples possible to collect in the environment. Therefore, information contained in honey gives good reflection of an average environment condition considering bioavailable elements and/or chemical compounds. Results of measured 1 37C s activities in different types of honey collected on the area of Republic of Croatia in period from 2000 to 2003 are given in this paper. The activity of 1 37C s is measured with gamma spectrometric method and the types of honey are defined on the basis of pollen analysis and from measuring electro conductivity. More than 15 years after the accident in Chernobyl, it is still possible to monitor 1 37C s activity in several types of honey. The greatest 1 37C s activities are detected in pure fir-tree and spruce honey-dew honey (15.7 ± 5.6 Bq/kg), mixed honey containing honey-dew (7.4 ± 3.9 Bq/kg) and in pure chestnut honey (4.5 ± 2.4 Bq/kg). On the other side, 1 37C s has not been found in any of the samples of pure lime- and locust-tree honeys, while in the meadow honey it has been detected only twice. Considering that measured activities of 1 37C s in honey correspond with the levels of contamination of particular areas, coniferous honey-dew honeys, as well as pure chestnut honey, can be used as bioindicators in monitoring the environment contaminated with 1 37C s.(author)

  19. Distribution of caesium-137 in the Mediterranean Sea

    International Nuclear Information System (INIS)

    Fukai, R.; Ballestra, S.; Vas, D.

    1980-01-01

    The International Laboratory of Marine Radioactivity (Monaco) conducted several oceanographic cruises during 1975-1977 to collect data on heavy metals and chlorinated hydrocarbons in the open Mediterranean. Sea water samples for radionuclide measurements were also collected on these cruises. The 137 Cs measurements in these samples are presented and discussed. After collection sea water was immediately acidified to pH 1.5 and 137 Cs was sorbed on solid ammonium phosphomolybdate together with added stable cesium carrier. After dissolution of AMP by NaoH, Cs was separated from K and Rb by ion exchange, precipitated as chloroplatinate and beta-counted. The surface concentrations of 137 Cs in the different areas of the Mediterranean fall in the range of 80-180 fCi 137 Cs/l, the average of all values being 126 +- 7 fCi 137 Cs. The vertical distribution of 137 Cs measured at four different locations varied considerably. It increased from surface to a maximum at a depth between 50m and 250m and then decreased with depth. The depth of maximum concentration differed from station to station but was always above the chlorinity maximum. The vertical distribution, therefore, seems to be closely related to vertical water mass movements. The inventories of 137 Cs delivered by radioactive fallout into the Mediterranean water columns are computed on the basis 137 Cs/ 90 Sr activity ratio and presented. (M.G.B.)

  20. Adsorption of Radioactive Strontium and Caesium from Mixtures of Solutions

    International Nuclear Information System (INIS)

    Haznedaroglu, H.N.

    2002-07-01

    In this thesis, the adsorption of the radioactive Cs and Sr on two different types of cement, Sulfate Resistant Cement and Portland Composed Cement, was investigated. The gamma-active Cs-137 and Sr-85 were used as tracers. Four different mixtures of solutions of Cs and Sr were used in experiments; a) The solution containing trace amount of Sr-85 and Cs-137 b) 1.10 - 5 - 1.10 - 1 M *SrCl 2 solutions containing trace amount of Cs-137 c) 1.10 - 5 - 1.10 - 1 M *CsCl solutions containing trace amount of Sr-85 d) The equal amount of mixtures of 1.10 - 5 - 1.10 - 1 M SrCl 2 and 1.10 - 5 - 1.10 - 1 M CsCl solutions. It was shown that the convenient ph values for the comparison of Cs and Sr adsorption on both cement were 2.5 and 11.0. It was observed that the adsorption capacity of Sr on Sulfate Resistant Cement was twice that for the Portland Composed Cement in the solutions containing trace amount of Cs-137 and 1.10 - 5 - 1.10 - 1 *SrCl 2 . The in cease in adsorption capacity is related to the Ca to Sr ion exchange in Sulfate Resistant Cement containing appreciable amount of C 3 S. The adsorption of Cs and Sr on both types of cement in solutions containing equal amount of CsCl and SrCl 2 was greater than that of individual solutions of CsCl and SrCl 2 . This latter behavior is related to the ion charge, the hydration of ions and the interaction of the Cs with the Sr on the surface of adsorbent. It was observed that although Portland Composed Cement adsorbs Cs selectively, Sulfate Resistant Cement has a greater affinity for Sr. Cs adsorption is not affected by ph changes whilst Sr adsorption is highly dependent on ph

  1. Assessment of Caesium -137 accumulation from soil to autochthonous weeds

    International Nuclear Information System (INIS)

    Sreenivasa Chari, M.; Karuna Sagar, G.; Manjaiah, K.M.

    2017-01-01

    A study was conducted at Nuclear Research Laboratory (NRL), IARI, New Delhi to obtain radio cesium ( 137 Cs) Soil-to-plant transfer factors of autochthonous weeds at low level of contamination, where contamination is a legacy of experimental activities. Studied area is sporadically covered with autochthonous weeds mainly with Amaranthus viridis, Cynodon dactylon, Cassia auriculata, Brachiaria mutica, Parthenium hysterophorus, Bohervia diffusa and some taxonomically unidentified weeds. Extractability as well as bioavailability of 137 Cs was quantified by sequential extraction. In the representative plant and soil samples, 137 Cs activity was measured directly with the 2.5” × 2.5” NaI (TI) well type detector installed in 15 cm thick lead shield and single channel gamma analyzer. Transfer factors of grassy weeds were 0.143 to 0.310 (1.43 × 10 -2 to 3.1 × 10 -2 ), for broad leaved weeds 0.103 to 0.133 (1.03 × 10 -2 to 1.33 × 10 -2 ). Increase in the activity levels increased the transfer factors of weeds. Irrespective of activity levels higher transfer factors were observed in roots ranging from 0.13 to 0.28 (1. 3 × 10 -1 to 2.8 × 10 -1 ). At both the levels (40 and 80 µci) Cynodon dactylon recorded higher root and shoot transfer factor of 2.99 and 0.29 respectively, when compared to other weeds. Significantly lower transfer factors were observed in Parthenium hysterophorus. Geochemical partitioning shown that the reducible phase (56%) is the largest sink for 137 Cs in the studied soils

  2. Societal representations on the accident with caesium-137

    International Nuclear Information System (INIS)

    Chaves, E.G.

    1998-01-01

    The influence of societal representations on the theme of nuclear energy are reviewed in the light of the public's reactions to the accident with the capsule of 137 Cs in Goiania. As a starting point, it is accepted that the panic caused by the accident can be properly understood only if human subjectivity is taken into consideration. This perspective is required whenever events unfold which put human life and the environment at risk. Faced with the accident, the public internalized radioactivity - an element unknown to them - as a certainty of contracting cancer and ultimately death, despite the fact that such outcomes can only be the result of excessive exposure to radioactivity. (author)

  3. Sorption behaviour of caesium on a bentonite sample

    International Nuclear Information System (INIS)

    Hurel, C.; Marmier, N.; Fromage, F.; Seby, F.; Bourg, A.C.M.; Giffaut, E.

    2002-01-01

    Sorption of elements like Cs on clay is one of the principal processes delaying their release from deep repositories of nuclear wastes into the environment. The sorption processes taking place between non-purified natural clay material (bentonite) and synthetic groundwater (containing Ca, Mg, Na, K and carbonates) were therefore studied experimentally and modelled for Cs to determine whether thermodynamic computer codes capable of predicting the behaviour of this element in natural systems might be developed. The model used, based on the properties of a pure montmorillonite phase, incorporates the surface reactions for natural major ions and sorbing cations but does not have any adjustable parameters. The weight of each parameters used in the model is assessed. Surface reactions are classified as either major or minor, and a simplified model of Cs sorption that considers only the major processes is proposed. This simplified model might correspond to the less sophisticated thermodynamic model included in coupled geochemistry-transport models. (orig.)

  4. Indirect determination of potassium, rubidium and caesium with mercury chloranilate

    International Nuclear Information System (INIS)

    Huber, H.; Raber, H.; Dvorak, K.; Kalcher, K.

    1982-01-01

    In the reaction of alkali-tetraphenylborates with mercury(II)-chloranilate, four moles of chloranilic acid are released per g ion of alkali metal. The chloranilic acid was determined photometrically at 332 or at 540 nm. With a molar extinction coefficient of 10 6 , this technique is one of the most sensitive wet chemical alkali determinations. In this way, ammonium and organic bases can be detected photometrically as tetraphenylborates provided that there is a stoichiometrically perfect composition. (author)

  5. Influence of temperature on elastic properties of caesium cyanide

    International Nuclear Information System (INIS)

    Singh, Preeti; Gaur, N.K.; Singh, R.K.

    2007-01-01

    An extended three body force shell model (ETSM), which incorporates the effects of translational-rotational (TR) coupling, three body interactions (TBI) and anharmonicity, has been applied to investigate the temperature dependence of the second order elastic constants (c ij , i,j=1,2) of CsCN. The elastic constant c 44 obtained by us shows an anomalous behaviour with the variation of temperature. The variations of elastic constants (c 11 , c 12 , c 44 ) with temperature are almost in excellent agreement with Brillouin scattering measured data. We have also evaluated the temperature variations of the third order elastic constants (c ijk ) and the pressure derivatives of the c ij in the CsCN material. However, their values could not be compared due to lack of experimental data. (copyright 2007 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  6. Modelling transport and deposition of caesium and iodine from the Chernobyl accident using the DREAM model

    Directory of Open Access Journals (Sweden)

    J. Brandt

    2002-01-01

    Full Text Available A tracer model, DREAM (the Danish Rimpuff and Eulerian Accidental release Model, has been developed for modelling transport, dispersion and deposition (wet and dry of radioactive material from accidental releases, as the Chernobyl accident. The model is a combination of a Lagrangian model, that includes the near source dispersion, and an Eulerian model describing the long-range transport. The performance of the transport model has previously been tested within the European Tracer Experiment, ETEX, which included transport and dispersion of an inert, non-depositing tracer from a controlled release. The focus of this paper is the model performance with respect to the total deposition of  137Cs, 134Cs and 131I from the Chernobyl accident, using different relatively simple and comprehensive parameterizations for dry- and wet deposition. The performance, compared to measurements, of using different combinations of two different wet deposition parameterizations and three different parameterizations of dry deposition has been evaluated, using different statistical tests. The best model performance, compared to measurements, is obtained when parameterizing the total deposition combined of a simple method for dry deposition and a subgrid-scale averaging scheme for wet deposition based on relative humidities. The same major conclusion is obtained for all the three different radioactive isotopes and using two different deposition measurement databases. Large differences are seen in the results obtained by using the two different parameterizations of wet deposition based on precipitation rates and relative humidities, respectively. The parameterization based on subgrid-scale averaging is, in all cases, performing better than the parameterization based on precipitation rates. This indicates that the in-cloud scavenging process is more important than the below cloud scavenging process for the submicron particles and that the precipitation rates are relatively uncertain in the meteorological model compared to the relative humidity. Relatively small differences are, however, seen in the statistical tests between the three different parameterizations of dry deposition.

  7. Variability of the strontium-90 and caesium-137 burden of native plants and animals

    Energy Technology Data Exchange (ETDEWEB)

    Eberhardt, L L

    1946-10-17

    Cesium-137 and /sup 90/Sr body burdens were determined in plants and animals at selected sites in Alaska, Idaho, Nevada, Utah, California, and Maryland, and coefficients of variations were derived. Coefficients of variation for burdens of /sup 90/Sr and /sup 137/Cs were suprisingly consistent over a wide range of plants and animals. Values for /sup 90/Sr ranged from about 0.30 to 0.45 while those for /sup 137/Cs appeared somewhat lower, ranging roughly from 0.25 to 0.35. Various factors possibly affecting individual sets of data were indicated. With one exception (Maryland white-tailed deer), the bone-strontium-90 values were calculated in terms of picocuries (10/sup -12/c) per g calcium (strontium units). Analysis of the Alaskan caribou data in terms of picocuries per g standard dry weight yields virtually the same coefficient of variation. The plant data were calculated on the standard dry weight basis, while soil-levels were on a unit area basis. All /sup 137/Cs values were expressed in units per g dry weight. Results reported here should not be interpreted as meaning that the coefficient of variation for levels of these two radionuclides is everywhere roughly constant.

  8. Availability of caesium isotopes in vegetation estimated from incubation and extraction experiments

    International Nuclear Information System (INIS)

    Salbu, B.; Oestby, G.; Garmo, T.H.; Hove, K.

    1992-01-01

    A rapid and inexpensive incubation and extraction technique for estimating the available low molecular weight and potentially bioavailable fraction of Cs isotopes in vegetation has been developed. Samples of contaminated vegetation (grass, herbage and fungi) and litter were exposed to rumen liquid from sheep, by in vitro incubation or by placing nylon bags in the rumen of sheep (in sacco). The results were compared with laboratory extractions using rumen buffer, NH 4 OAc, CsCl and de-ionized water. The release of low molecular weight 137 Cs species after in vitro incubation with rumen liquid for 4-8 h was 75-85% for grass, herbage and fungi, 30% for lichen and 10% for litter. The reproducibility of the method was 5% for digestible matrices and 10-20% for litter where the fraction of Cs isotopes released was small. Extractions with NH 4 OAc and CsCl released 75 and 80% of the Cs isotopes in grass, respectively. Significantly lower extraction yields were obtained with de-ionized water and buffer. During in sacco incubation, 90-100% of the Cs isotopes in vegetation was released within 1 h; however, potentially available low molecular weight forms and Cs-bearing colloidal material could not be differentiated. The results obtained by incubation with rumen liquid and by extraction with NH 4 OAc or CsCl were in good agreement with published data from a 3 week feeding trial. For practical reasons extraction with NH 4 OAc or CsCl rather than incubation with rumen liquid is recommended for estimating the fraction of available low molecular weight Cs species. Results from incubation with rumen liquid showed that the availability of Cs isotopes in grass collected in 1986 was low (15%), but increased with time up to 1989 (75-80%). It is probable that the high fraction of inert 137 Cs species reflects surface contamination in 1986. (author)

  9. Radioactive caesium contamination in human milk in Italy after the Chernobyl accident

    International Nuclear Information System (INIS)

    Venuti, G.C.; Risica, S.; Rogani, A.

    1991-01-01

    A systematic study of human milk contamination due to the Chernobyl fall-out was conducted from May 1986 to December 1988 in the Rome area. A comparison was made with the contamination in the same period in other infant food, that is, cows' and powdered milk. The thyroid and effective dose equivalent for breast fed infants born in different periods were evaluated. Using average main food contamination data in the same area, an assessment of the transfer coefficient between the mothers' diet and their milk was performed. 40 K content of this milk was also measured and is discussed in the paper. An extension of the sampling to other areas was made in 1987 and 1988. (author)

  10. Eating meat with cesium and in vitro measurement; Fleisch mit Caesium essen und in vitro messen

    Energy Technology Data Exchange (ETDEWEB)

    Philipsborn, Henning von [Regensburg Univ. (Germany). Fakultaet Physik

    2017-08-01

    Wild pig meat contains in several regions still several thousand Bq per kg Cs-137, especially during spring. ICRP publication 56 specifies an effective half life of Cs-137 for man 50 to 150 days. In vivo measurements using whole-body counters are used for monitoring. In vitro measurements of excretion samples over several months are described in the contribution.

  11. Application of crown-ethers to caesium and strontium removal from Marcoule reprocessing concentrate

    International Nuclear Information System (INIS)

    Dozol, J.F.; Garcia, J.C.i; Sastre, A.M.

    1991-01-01

    The liquid wastes arising from reprocessing plants are treated by evaporation, the distillate is discharged into environment and the concentrate containing all the active and inactive salts must be stored in geological formation, after embedding, due to the activity of long life radionuclides (actinides, Cs, Sr). The object of the work is to remove actinides and cesium/strontium from high sodium content acidic concentrated in order to sharply decrease the volume of wastes to be stored in geological formation. (author)

  12. Monitoring the genetic health of persons in Goiania accidentally exposed to ionizing radiation from caesium-137

    International Nuclear Information System (INIS)

    Da Cruz, A.D.; Glickman, B.W.

    1998-01-01

    This work describes the long term genetic monitoring of the Goiania population exposed to ionizing radiation from 137 Cs, using cytogenetic and molecular endpoints. Cytogenetically, micronucleus frequencies differentiated groups exposed to different levels of radiation. Two molecular methods were employed: 1) the hprt clonal assay, involving in vitro selection of 6-thioguanine-resistant hprt mutant clones which were characterized at the molecular level using RT-PCR and genomic analysis. Ionizing radiation exposure initially elevated hprt mutation frequency which gradually diminished, so that no significant increase was observed four and a half years after original exposure. The spectrum of hprt mutations recovered from ten individuals exposed to relatively high doses of radiation revealed a fourfold increase in the frequency of A:T → G:C transitions. The increase is consistent with the effects of ionizing radiation in prokaryotes and lower eukaryotes. Additionally, a twofold increase in the frequency of deletions was observed which may reflect radiation induced DNA strand breakage; 2) determination of microsatellite instability using fluorescent PCR and genomic DNA from mononuclear cells. The frequency distributions of somatic microsatellite alterations in exposed and non-exposed populations were not different. Our assay lacked sensitivity to discriminate between spontaneous and induced microsatellite instability and therefore, is not suitable for population monitoring. Finally, we estimated the risk associated with radiation exposure for the exposed Goiania population. The estimated genetic risk of dominant disorders in the first post-exposure generation was increased nearly twenty-fourfold. The risk of carcinogenesis was increased by a factor of 1.5. (author)

  13. Instrumental analysis by gamma spectrometry of low level caesium-137 in marine samples

    International Nuclear Information System (INIS)

    Figueira, R.C.L.; Silva, L.R.N.; Figueiredo, A.M.G.; Cunha, I.I.L.

    1998-01-01

    An instrumental method for the analysis of low levels of 137 Cs in marine samples consists in calibrating the detector, determining the counting efficiency of the detector, accumulative counts of background and sample and smoothing the 661.6 keV photopeak. The methodology was applied to reference samples containing low levels of 137 Cs, showing a good accuracy. It was further applied to sediment samples from the southern coast of Brazil. The levels obtained ranged between 1.0 and 1.8 Bq.kg -1 , and the lower limit of detection and minimum detectable concentration values were 10 mBq and 0.28 Bq.kg -1 , respectively. (author)

  14. Spatial variability of caesium-137 activities in soils in the Jura mountains

    International Nuclear Information System (INIS)

    Pimou-Heumou, G.; Lucot, E.; Crini, N.; Briot, M.; Badot, P.M.

    2011-01-01

    275 soil samples were taken in the catchment area of the upper part of the Doubs river located in the Jura mountains according to a sampling strategy designed to evaluate the extent of the spatial variability of 137 Cs activities and to identify its main sources. 137 Cs activities ranged between about 1000 and 12000 Bq.m -2 with an average of approximately 3600 Bq.m -2 . The spatial variability of the contamination is high: 137 Cs activity shows statistically significant links with altitude, soil organic matter and land cover, whereas the other studied parameters, i.e. soil type and topographic position, do not constitute significant sources of variation. These results are discussed in terms of evaluation of the radioactive contamination on a regional scale. They show that to be satisfactory, a sampling strategy must necessarily take into account the various types of land cover. (authors)

  15. A survey of caesium-137 and plutonium in British soils in 1977

    International Nuclear Information System (INIS)

    Cawsw, P.A.; Horrill, A.D.

    1986-02-01

    Measurements have been made of the accumulation to 30 cm depth of Cs-137 and plutonium in soils from permanent grassland and woodland in England, Scotland and Wales, and of the concentrations in grass. In Scotland, peat has also been sampled. The sampling points were carefully selected with due regard to their soil type and future permanence, to establish a network of grassland sites at which radionuclide concentrations may be measured over the long-term. The main objective of the survey is to provide information on the integrated deposition of Cs-137, Pu-239+240 and Pu-238 from the atmosphere to provide a baseline in 1977 with which to assess the significance of radioactive accumulations from the routine operation of nuclear facilities. Further objectives are to study the transfer of radionuclides to vegetation, and to compare the concentrations with generalised derived limits for radiological assessment. (author)

  16. Factors affecting the leachability of caesium and strontium from cemented simulant evaporator wastes

    International Nuclear Information System (INIS)

    Lee, D.J.; Brown, D.J.

    1981-08-01

    Leach rates of stable cesium and strontium from a range of simulated evaporator waste/cement formulations have been determined. Important factors in plant operation are assessed for their effect on leach rates. Increasing the curing time and lowering the water/cement ratio has been shown to reduce leach rates by up to a factor of four. Incorporation of additives such as clays and supplementary cementatious materials can reduce leach rates by up to three orders magnitude, and coating the surface of the waste form with a neat cement grout can reduce the cesium leach rate by up to four orders of magnitude. The effects of permeability of the matrix and its cesium absorption capacity on the leach rates have been analysed qualitatively. (U.K.)

  17. Caesium-137 in the foodchain lichen-reindeer-man during 1976 to 1978

    International Nuclear Information System (INIS)

    Tillander, M.; Jaakkola, T.; Miettinen, J.K.

    1978-01-01

    The behaviour of the 137 Cs isotope in the subarctic environment has been an object of investigations in this laboratory since 1960. The 137 Cs body burden of a group of about 100 Lapps has been determined annually each spring since 1962 using a mobile whole-body counting system accommodated in a truck. In spring 1977, 31 reindeer herders and reindeer herding fishermen residing in Inari were thus measured. In spring 1978, no 137 Cs body burden measurements of the Lapps were carried out. Instead, analysis of 137 Cs in lichen and reindeer muscle samples was continued in order to check possible changes in the environmental 137 Cs level. In this paper 137 Cs concentrations in lichen in 1977 and in reindeer muscle in 1977 and 1978 are reported. Using these results the 137 Cs body burden of Finnish Lapps is estimated

  18. The behaviour of caesium-137 in oxisols and in the Goiania soil

    Energy Technology Data Exchange (ETDEWEB)

    Wasserman, M A [Comissao Nacional de Energia Nuclear, Instituto de Radioprotecao e Dosimetria, Rio de Janeiro (Brazil)

    1998-12-01

    The {sup 137}Cs soil-to-plant transfer factors obtained in oxisols accidentally contaminated in Goiania and in artificially contaminated soils are found to be higher than those of soils in temperate climates. These differences are discussed in the light of pedology and geochemical partitioning. Tropical soil characteristics such as acidity, the low availability of nutritive elements and low content of 2:1 clay types seem to determine a high availability of {sup 137}Cs. The results of sequential extraction showed {sup 137}Cs weakly bound to soil components and underlines the importance of Fe oxides in the control of the {sup 137}Cs in topical climates. (author) 25 refs, 2 figs, 2 tabs

  19. Effective Half-Life of Caesium-137 in Various Environmental Media at the Savannah River Site

    Energy Technology Data Exchange (ETDEWEB)

    Paller, M. H.; Jannik, G. T.; Baker, R. A.

    2014-05-01

    During the operational history of the Savannah River Site (SRS), many different radionuclides have been released from site facilities into the SRS environment. However, only a relatively small number of pathways, most importantly 137Cs in fish and deer, have contributed significantly to doses and risks to the public. The “effective” half-lives (Te) of 137Cs (which include both physical decay and environmental dispersion) in Savannah River floodplain soil and vegetation and in fish and white-tailed deer from the SRS were estimated using long-term monitoring data. For 1974–2011, the Tes of 137Cs in Savannah River floodplain soil and vegetation were 17.0 years (95% CI = 14.2–19.9) and 13.4 years (95% CI = 10.8–16.0), respectively. These Tes were greater than in a previous study that used data collected only through 2005 as a likely result of changes in the flood regime of the Savannah River. Field analyses of 137Cs concentrations in deer collected during yearly controlled hunts at the SRS indicated an overall Te of 15.9 years (95% CI = 12.3–19.6) for 1965–2011; however, the Te for 1990–2011 was significantly shorter (11.8 years, 95% CI = 4.8–18.8) due to an increase in the rate of 137Cs removal. The shortest Tes were for fish in SRS streams and the Savannah River (3.5–9.0 years), where dilution and dispersal resulted in rapid 137Cs removal. Long-term data show that Tes are significantly shorter than the physical half-life of 137Cs in the SRS environment but that they can change over time. Therefore, it is desirable have a long period of record for calculating Tes and risky to extrapolate Tes beyond this period unless the processes governing 137Cs removal are clearly understood.

  20. PROBLEMS OF PROTECTION OF URBAN AREAS FROM RADIONUCLIDES STRONTIUM-90 AND CAESIUM-137 AFTER TECHNOLOGICAL DISASTERS

    Directory of Open Access Journals (Sweden)

    Olga Cheremisina

    2017-05-01

    Full Text Available The methods of decontamination of radionuclides from soils are considered. The literature focuses on fixing radionuclides in soils and creating geochemical barriers that it is prevent the spread of pollution. The main disadvantage of these methods is exclude the possibility of building a territory. It is need to clean up the area to the sanitary and hygienic requirements for further use and then it is desirable to fix the residual activity. Carried out an analysis of forms of radionuclides fixation in soils and mechanics of this fixation, therewith revealed that Cs-137 fixed more strongly on mineral component of soil, than Sr-90, which is mainly in the acid-soluble and exchangeable form, and, as a consequence, passes into the liquid phase during soil deactivation more easily. Contaminated soil deactivation in the urbanized territory is possible by washing it by ferric chloride solution at a concentration 0.02-0.05 M and with an equimolar addition of an ammonium chloride. Therewith most efficient methods, which used in-situ conditions, are heap and convection leaching technologies with treatment degree, which not less than 80%. At the same time, the most efficient methods which used in-situ conditions are heap and the convection leaching. The hardware-technological scheme of a convection leaching is presented. Noted that ammonium salts additions slightly rising coefficient of treatment from Sr-90. Because ammonium salts aren’t expensive, their additions allow to obtain significant economic benefits due to decreasing of ferric chloride consumption, which is more valuable, and waste water volume reduction.

  1. Depth determination of buried caesium-137 and cobalt-60 sources using scatter peak data

    International Nuclear Information System (INIS)

    Adams, J. C.; Joyce, M. J.; Mellor, M.

    2009-01-01

    An investigation into an alternative approach to 3D (3-dimensional) source mapping is proposed, by combining the insights of two existing techniques. The first of these is a 3D 'imaging' tool, N-Visage TM that has been developed by REACT Engineering Ltd. This technique is efficient and robust, but is not a true 3D technique as it relies on user-supplied 2D (2-dimensional) manifolds to constrain source locations. The second technique uses the γ-photopeak and an X-ray peak to determine radionuclide source depth using a relative attenuation method. We look at the possibility of combining both techniques to constrain both the location and depth of a radiological source buried under shielding. It is believed a combined method using spectra recorded above the shielding object will be of use in the nuclear decommissioning and land contamination industries. N-Visage TM has previously been used to map source distributions of mixed radionuclides with complex geometries through shielding media. The software works by producing a computer model which recreates the experimental setup. A survey is imported, comprising a set of γ-spectra recorded with an instrument of known efficiency and isotropy taken at a variety of locations around the area of interest. A survey plan recording the location and orientation of the instrument for each reading is also reconstructed. N-Visage TM is then able to determine the locations of the source(s) without prior knowledge of exactly where they are located, by building and inverting a simple physical model relating potential source locations to the recorded spectra. This research sets out to investigate the possibility of combining the geometric insights of N-Visage TM with a method of extracting depth information from scatter data, rather than the X-ray peak. By combining the γ-photopeak and scatter areas of a spectrum, the thickness of the shielding media between source and detector can potentially be inferred. Using scattered photons rather than X-ray attenuation is preferable where depths are of a sufficient thickness to effectively eliminate a measurable X-ray photopeak. (authors)

  2. Bioavailability of caesium-137 from chernozem soils with high and low levels of radioactive contamination

    Science.gov (United States)

    Paramonova, Tatiana; Shamshurina, Eugenia; Machaeva, Ekaterina; Belyaev, Vladimir

    2014-05-01

    Bioavailability of Cs-137 in "soil-plant" system of radioactively contaminated terrestrial ecosystems is the most important factor in the understanding of ecological situation. There are many factors affecting the features of Cs-137 biogeochemical cycle: period since an accident, type and intensity of radioactive fallout, general properties of landscape and the specifics of soil and plant covers, etc. In order to evaluate the importance of soil contamination level for the process of Cs-137 translocation from soil to plant the research in forest-steppe areas of Russia with similar natural properties, but contrasting high (Tula region) and low (Kursk region) levels of radioactive Chernobyl fallout (about 25 years after accident) was conducted. Soil cover of both sites is presented by chernozems with bulk density 1.1-1.2 g/cm3, 6-7% humus and neutral pH 6.5-7.2; plant cover under investigation consist of dry and wet meadows with bioproductivity 1.6-2.5 kg/m2 and 85-90% of biomass concentrated underground, that is typical for Russian forest-steppe landscapes. At the same time levels of soil regional contamination with Cs-137 differ by an order - 620-710 Bq/kg (210-250 kBq/m2) in Tula region and 30-55 Bq/kg (10-20 kBq/m2) in Kursk region. At a higher level of soil radioactive contamination specific activity of Cs-137 in vegetation of meadows is noticeably increased (103-160 Bq/kg in Tula region versus 12-14 Bq/kg in Kursk region) with correlation coefficient r 0.87. Increasing of Cs-137 in the underground parts of plants plays a decisive role in this process, while the specific radionuclide's activity in the aboveground parts of different sites is almost invariant (and ubiquitously roots contain 2-5 times more Cs-137 than shoots). The values of transfer factors for Cs-137 (the ratio of the specific Cs-137 activities in the plant tissue and in the soil) at various levels of soil radioactive contamination vary within a relatively narrow range 0.1-0.4, that confirms the discrimination in the radionuclide root uptake. And the higher the level of soil contamination, the more pronounced decreasing of Cs-137 transfer factors with correlation coefficient r -0.89. Further, transfer factors of Cs-137 for aboveground parts of meadow vegetation consist of 0.03-0.012 and always are 2-4 times lower than transfer factors for underground parts. This suggests an existence of biological barrier between the roots and shoots and suppression in the translocation of Cs-137s into aboveground parts of plants. Moreover bioavailability of Cs-137 in the sites of wet meadows is, in accordance with the transfer factors values, even a few more then in the sites of dry meadows regardless of the level of soil radioactive contamination. Thus, general parameters of radionuclide's accumulation in vegetation is closely dependent on its supplies in soil. However, the proportion of Cs-137 root uptake isn't determined by the level of soil radioactive contamination, but mostly by the biological features of vegetation. Study was conducted with the support from the Russian Foundation for Basic Research (project no. 14-05-00903).

  3. A comparison of stable caesium uptake by six grass species of contrasting growth strategy

    International Nuclear Information System (INIS)

    Willey, N.J.; Martin, M.H.

    1997-01-01

    Six plants in the family Gramineae were used to investigate the relationship between Cs uptake, nutrient regime and plant growth strategy sensu Grime (1979: Plant Growth Strategies and Vegetation Processes, John Wiley). The roots of 66 day old Elymus repens (L.) Gould., Bromus sterilis L., Agrostis stolonifera L., Anthoxanthum odoratum L., Festuca ovina L. and Nardus stricta L. plants grown in acid-washed sand at high and low nutrient levels were exposed to a 96 h pulse of stable Cs at 0.05 mM, 0.15 mM, 0.3 mM, 1.0 mM and 3.0 mM concentrations. Different nutrient regimes induced large differences in dry wt in E. repens, B. sterilis and A. stolonifera plants but only small differences in N. stricta and F. ovina plants. At high nutrient concentrations, A. stolonifera, A. odoratum, F. ovina and N. stricta shoots showed significantly greater increases in internal Cs concentration with rising external Cs concentrations than did E. repens and B. sterilis shoots. The relationship between increases in shoot and external Cs concentrations was statistically indistinguishable between species in plants grown at the low nutrient concentration. These patterns of Cs uptake ensured that with long-term high K concentrations the more competitive plants (E. repens and B. sterilis) accumulated higher concentrations of Cs from low external concentrations than did non-competitive plants or competitive plants grown at low nutrient levels. It is suggested that the relationship between plant growth strategy sensu Grime (1979) and Cs accumulation patterns may help to explain the different concentrations to which species accumulate radiocaesium from the soil. (author)

  4. Iodine-129 and Caesium-137 in Chernobyl contaminated soil and their chemical fractionation

    DEFF Research Database (Denmark)

    Hou, Xiaolin; Fogh, C.L.; Kucera, J.

    2003-01-01

    Soil samples from areas in Belarus, Russia and Sweden contaminated by the Chernobyl accident were analysed for I-129 by radiochemical neutron activation analysis, as well as for Cs-137 by gamma-spectrometry. The atomic ratio of I-129/(CS)-C-137 in the upper layer of the examined soil cores ranged...... from 0.10 to 0.30, with an average of 0.18, and no correlation between I-129/Cs-137 ratio and the distance from Chernobyl reactor to sampling location was observed. It seems feasible to use the I-129/Cs-137 ratio to reconstruct the deposition pattern of I-131 in these areas. The association of I-129...... and (CS)-C-137 in the Chernobyl soil and Irish Sea sediment was investigated by a sequential extraction method. Similar speciation of I-129 in the Chernobyl soil and Irish Sea sediment was found. Approximately 70% of I-129 is bound to oxides and organic matter, and 10-20% is in the readily available phase...

  5. Does the Fukushima NPP disaster affect the caesium activity of North Atlantic Ocean fish?

    International Nuclear Information System (INIS)

    Kanisch, G.; Aust, M.O.

    2013-01-01

    Fillet samples of marine fish collected from the East/West Greenland currents (GC) and from the Baltic Sea (BS) have been investigated by gamma-ray spectrometry within the regular German monitoring programme. In samples of the second half of 2011, "1"3"4Cs traces have been detected that are suggested to originate from the Fukushima fallout that was deposited in March/April 2011 over the northern North Atlantic and accumulated by fish. The radionuclide "1"3"4Cs (half-life 2 yr) was indeed detected with quite small activities at about 0.0036 Bq kg"-"1 w.w. Existing box models describing the transport of Cs within seawater boxes of the northeast Atlantic allowed for estimation of "1"3"4Cs contributions from other sources, i.e. from the Chernobyl fallout and from discharges by the two major European nuclear reprocessing plants; both were negligible around Greenland, while for the Chernobyl fallout a small "1"3"4Cs background contribution to BS fish was estimated. Model results confirmed the level of "1"3"4C measured in BS fish and showed its maximum to have occurred in winter 2011/2012 followed by a continuous decrease. It was also determined that "1"3"4Cs activity, but not that of "1"3"7Cs, showed a significant negative correlation with sampling depth (150-400 m) of GC fish; this strengthens our Fukushima fallout assumption. As a result, the Fukushima fallout in these sea areas only marginally enhanced (GC: 4%; BS: 0.1%) pre-Fukushima levels of individual dose rates received by human fish consumers; the addition was around 0.001 μSv following the consumption of 10 kg of fish per year, which is not expected to cause concern according to present guidelines for radiation protection.

  6. Non cancerous diseases following a chronic intern contamination by caesium 137: cataracts and cardiac arrhythmias

    International Nuclear Information System (INIS)

    Landon, G.

    2008-07-01

    This work of thesis joins within the framework of an analysis of the sanitary consequences of the nuclear accident of Chernobylsk. Since 2005, the I.R.S.N. is interested in the not cancerous pathologies (cataracts, and cardiac arrhythmias) observed among the children living on the contaminated territories after the fallout of Chernobylsk and has in this aim implemented a research programme called E.P.I.C.E. (Evaluation of the pathologies induced by a chronicle contamination by cesium) whom objective is to show an eventual link between the chronicle ingestion of contaminated food and these pathologies emergence. An exploitation of the results of the pilot study,first phase of the E.P.I.C.E. program was realized. The analysis was completed by two bibliographical reviews relative to the knowledge available on these diseases. The results of this pilot study suggest: on one hand, an absence of link between the activity in cesium 137 at the level of the heart, of the whole body and the emergence of disorder of the heart rhythm; on the other hand, for the cases of cataract, a link between the load in cesium 137 at the neck level and the emergence of the disease in 40 % of the cases. However, these results must be considered with caution because several limits and, in particular, a way of selection affect this study. concerning the scientific literature, this one stays rather poor because only thee articles make reference to a relationship between cesium 137 and the emergence of these non cancerous pathologies. After having exposed the context, this thesis draws up the situation of knowledge relative to cataracts and to cardiac arrhythmias and their possible relationship with ionizing radiations, collect the results stemming from the analysis of the pilot study and envisages future epidemiological studies. (N.C.)

  7. Measurement of caesium-137 in the human body using a whole body counter

    Science.gov (United States)

    Elessawi, Elkhadra Abdulmula

    Gamma radiation in the environment is mainly due to naturally occurring radionuclides. However, there is also a contribution from anthropogenic radionuclides such as 137Cs which originate from nuclear fission processes. Since 1986, the accident at the Chernobyl power plant has been a significant source of artificial environmental radioactivity. In order to assess the radiological impact of these radionuclides, it is necessary to measure their activities in samples drawn from the environment and in plants and animals including human populations. The whole body counter (WBC) at the University Hospital of Wales in Cardiff makes in vivo measurements of gamma emitting radionuclides using a scanning ring of six large-volume thallium-doped sodium iodide (Nal(Tl)) scintillation detectors. In this work the WBC was upgraded by the addition of two high purity germanium (HPGe) detectors. The performance and suitability of the detection systems were evaluated by comparing the detection limits for Cs. Sensitivities were measured using sources of known activity in a water filled anthropomorphic phantom and theoretical minimum detectable count-rates were estimated from phantom background pulse height spectra. The theoretical minimum detectable activity was about 24 Bq for the combination of six Nal(Tl) detectors whereas for the individual HPGe detectors it was 64 Bq and 65 Bq, despite the much improved energy resolution Activities of 137Cs in the human body between 1993 and 2007 were estimated from the background Nal(Tl) spectra of 813 patients and compared with recent measurements in 14 volunteers. The body burden of Cs in Cardiff patients increased from an average of about 60 Bq in the early and mid 1990s to a maximum of about 100 Bq in 2000. By 2007 it had decreased to about 40 Bq. This latter value was similar to that of Cardiff residents at the time of the Chernobyl accident and to that of the volunteers measured in 2007 (51 Bq). However, it was less than the mean activity of Cardiff residents in 1988 (130 Bq) indicating an overall decrease over a period of about 20 years. The variation in the in vivo activity is probably due to complex inter-relationships between a number of factors such as the removal of deposited 137Cs into the sea by rainfall, individual dietary choices, the imposition and removal of restrictions on foodstuffs from Chernobyl-affected areas and travel to countries that suffered greater initial fall-out than the UK.

  8. Polonium-210 and Caesium-137 in lynx (Lynx lynx), wolverine (Gulo gulo) and wolves (Canis lupus)

    International Nuclear Information System (INIS)

    Gjelsvik, Runhild; Holm, Elis; Kålås, John Atle; Persson, Bertil; Åsbrink, Jessica

    2014-01-01

    Wolves, lynx and wolverines are on the top of the food-chain in northern Scandinavia and Finland. 210 Po and 137 Cs have been analysed in samples of liver, kidney and muscle from 28 wolves from Sweden. In addition blood samples were taken from 27 wolves. In 9 of the wolves, samples of muscle, liver and blood were analysed for 210 Po. Samples of liver and muscle were collected from 16 lynx and 16 wolverines from Norway. The liver samples were analysed for 210 Po and 137 Cs. Only 137 Cs analyses were carried out for the muscle samples. The wolves were collected during the winter 2010 and 2011, while the samples for lynx and wolverines were all from 2011. The activity concentrations of 210 Po in wolves were higher for liver (range 20–523 Bq kg −1 d.w.) and kidney (range 24–942 Bq kg −1 d.w.) than muscle (range 1–43 Bq kg −1 d.w.) and blood (range 2–54 Bq kg −1 d.w.). Activity ratios, 210 Po/ 210 Pb, in wolf samples of muscle, liver and blood were in the ranges 2–77, 9–56 and 2–54. Using a wet weight ratio of 3.8 the maximal absorbed dose from 210 Po to wolf liver was estimated to 3500 μGy per year. Compared to wolf, the ranges of 210 Po in liver samples were lower in lynx (range 22–211 Bq kg −1 d.w.) and wolverine (range16–160 Bq kg −1 d.w.). Concentration of 137 Cs in wolf samples of muscle, liver, kidney and blood were in the ranges 70–8410 Bq kg −1 d.w., 36–4050 Bq kg −1 d.w., 31–3453 Bq kg −1 d.w. and 4–959 Bq kg −1 d.w., respectively. 137 Cs in lynx muscle and liver samples were in the ranges 44–13393 Bq kg −1 d.w. and 125–10260 Bq kg −1 d.w. The corresponding values for 137 Cs in wolverine were 22–3405 Bq kg −1 d.w. for liver and 53–4780 Bq kg −1 d.w. for muscle. The maximal absorbed dose from 137 Cs to lynx was estimated to 3000 μGy per year. - Highlights: • Annual doses from 210 Po are 1.4, 1.0 and 3.4 mGy for lynx, wolverine, and wolf. • Annual doses from 137 Cs are 3.3, 1.5 and 3.6 mGy for lynx, wolverine and wolf. • 210 Po/ 137 Cs ratios in wolf liver ranges from 0.01 to 4.0 and 0.002 to 0.05 in muscle. • The large spread in the data is due to the distribution of 137 Cs from Chernobyl. • The accumulation of 210 Po in liver and kidney is higher than for 137 Cs

  9. Experimental contamination of margaritana margaritifera (L) (a Fresh water bivalve) by caesium 137

    International Nuclear Information System (INIS)

    Foulquier, L.; Bovard, P.; Grauby, A.

    1966-01-01

    The hydro biological research carried out in the Radio-Ecology Section has led the authors to study some Margaritana sampling stations situated down-stream from the Monts d'Arree nuclear power station. They describe the preservation and contamination methods used for fixing the 137 Cs concentration factors in the case of Margaritana Margaritifera (L). The results of experiments carried out over a period of one hundred days show that the specific activity of the various organs is stabilized after thirty to thirty-five days. The authors have noticed a relatively low adsorption on the shell through the intermediary of micro-organisms, and a strong and rapid absorption in the soft parts. The concentration factors have values, at equilibrium, of around: 9 for the shell, 300 for all the organs, and 38 for the whole animal. A comparison of these results with work published by other authors makes it possible to draw general conclusions concerning the mechanism of 137 Cs fixation by lamellibranch, as well as their capacity of fixation. (author) [fr

  10. The distributions of chemical elements and Caesium-137 in the Northern-Crimean canal ecosystem

    International Nuclear Information System (INIS)

    Lazorenko, G.

    1998-01-01

    The distributions in 1992-1995 of some chemical elements and 137 Cs concentrations in components of the Northern-Crimean Canal (NCC) ecosystem and agricultural fields of the Kherson District and the Northern Crimea irrigated by the Dnieper River water are presented in the work. Five main sampling were selected between the Kakhovka Reservior (at the beginning of the NCC) and the Karkinitsky Bay along the 150 km of the main Canal. Two additional stations were selected in discharge canals to study of the role of irrigated agricultural fields in the accumulation of 137 Cs and chemical elements from water. (author)

  11. Influence of chemical composition of precipitation on migration of radioactive caesium in natural soils

    International Nuclear Information System (INIS)

    Thørring, H.; Skuterud, L.; Steinnes, E.

    2014-01-01

    The aim of the present work was to study the impact of the chemical composition of precipitation on radiocaesium mobility in natural soil. This was done through column studies. Three types of precipitation regimes were studied, representing a natural range found in Norway: Acidic precipitation (southernmost part of the country); precipitation rich in marine cations (highly oceanic coastal areas); and low concentrations of sea salts (slightly continental inland areas). After 50 weeks and a total precipitation supply of ∼10 000 L m −2 per column, results indicate that acidic precipitation increased the mobility of 134 Cs added during the experiment. However, depth distribution of already present Chernobyl fallout 137 Cs was not significantly affected by the chemical composition of precipitation. - Highlights: • Mobility of freshly added Cs-134 was higher in soil receiving acidic precipitation. • Depth penetration of Cs-134 was higher in soil profiles with a thicker humus layer. • Depth distribution of Chernobyl Cs-137 was not affected by precipitation type

  12. Uptake of caesium-137 from peat and compost mould by vegetables in a greenhouse experiment

    International Nuclear Information System (INIS)

    Malm, J.; Uusi-Rauva, A.; Paakkola, O.

    1991-01-01

    A pot experiment was conducted to study the root uptake of 137 Cs by vegetables grown in peat and composite mould in a greenhouse. The 137 Cs in the growing media originated from Chernobyl fallout. The vegetables were cucumber (Cucumis sativus L. var. Farbio VDP SF 76), tomato (Lycopersicon esculentum L. Var. Virosa), parsley (Petroselinum crispum A.W. Hill var. Non plus ultra), radish (Raphanus Sativus L. var. Nondan) and lettuce (Lactuca sativa L. var Atraktion). The effect of adding potassium to the peat was also studied. The transfer factors (activity in plant dry weight/activity in soil dry weight) varied from 0.66 to 1.8 for peat and from 0.060 to 0.19 for compost mould. Addition of potassium did not have any clear effect on the transfer factors. (Author)

  13. Structure and properties of molecular and ionic clusters in vapour over caesium fluoride

    Science.gov (United States)

    Mwanga, Stanley F.; Pogrebnaya, Tatiana P.; Pogrebnoi, Alexander M.

    2015-06-01

    The properties of neutral molecules Cs2F2, Cs3F3, and Cs4F4, and positive and negative cluster ions Cs2F+, CsF2-, Cs3F2+, Cs2F3-, Cs4F3+, and Cs5F4+ were studied by several of quantum chemical methods implementing density function theory and Möller-Plesset perturbation theory of second and fourth orders. For all species, the equilibrium geometrical structure and vibrational spectra were determined. Different isomers have been revealed for the trimer neutral molecule Cs3F3; pentaatomic, both positive and negative, Cs3F2+, Cs2F3-; and heptaatomic Cs4F3+ ions. The most abundant isomers in the saturated vapour were determined. Enthalpies of dissociation reactions and enthalpies of formation of the species were obtained.

  14. Iodine-129 and Caesium-137 in Chernobyl contaminated soil and their chemical fractionation

    Czech Academy of Sciences Publication Activity Database

    Hou, XL.; Fogh, CL.; Kučera, Jan; Andersson, KG.; Dahlgaard, H.; Nielsen, SP.

    2003-01-01

    Roč. 308, 1, 2, 3 (2003), s. 97-109 ISSN 0048-9697 R&D Projects: GA AV ČR IPP1050128; GA AV ČR KSK4055109 Institutional research plan: CEZ:AV0Z1048901 Keywords : iodine * neutron activation analysis Subject RIV: DN - Health Impact of the Environment Quality Impact factor: 1.455, year: 2003

  15. Caesium-137 behaviour in small agricultural catchments on the area of the Chernobyl contamination

    International Nuclear Information System (INIS)

    Kvasnikova, E.V.; Stukin, E.D.; Golosov, V.N.; Ivanova, N.N.; Panin, A.V.

    1999-01-01

    The vertical distribution of 137 Cs from the Chernobyl accident in soils of the basin of the Gusinaya Lapka dry river, situated in the Eastern region, 550 km from the reactor, has been investigated. In this area the 137 Cs contamination levels range between 250 and 502 kBq.m -2 . In the accumulation zones, at the bottom of the valley, the sediment deposits over the last ten years represent a layer of not more than 10 cm. On arable lands, the erosion processes are limited and no perceptible redistribution of 137 Cs could be observed, except at the transition between ploughed lands on the inter-rivers and meadows on the Balka slopes. This study demonstrates the potential use of the 137 Cs from the Chernobyl accident for the quantification of the soil erosion process. (author)

  16. Does the Fukushima NPP disaster affect the caesium activity of North Atlantic Ocean fish?

    Energy Technology Data Exchange (ETDEWEB)

    Kanisch, G.; Aust, M.O. [Thuenen Institute of Fisheries Ecology, Hamburg (Germany)

    2013-07-01

    Fillet samples of marine fish collected from the East/West Greenland currents (GC) and from the Baltic Sea (BS) have been investigated by gamma-ray spectrometry within the regular German monitoring programme. In samples of the second half of 2011, {sup 134}Cs traces have been detected that are suggested to originate from the Fukushima fallout that was deposited in March/April 2011 over the northern North Atlantic and accumulated by fish. The radionuclide {sup 134}Cs (half-life 2 yr) was indeed detected with quite small activities at about 0.0036 Bq kg{sup -1} w.w. Existing box models describing the transport of Cs within seawater boxes of the northeast Atlantic allowed for estimation of {sup 134}Cs contributions from other sources, i.e. from the Chernobyl fallout and from discharges by the two major European nuclear reprocessing plants; both were negligible around Greenland, while for the Chernobyl fallout a small {sup 134}Cs background contribution to BS fish was estimated. Model results confirmed the level of {sup 134}C measured in BS fish and showed its maximum to have occurred in winter 2011/2012 followed by a continuous decrease. It was also determined that {sup 134}Cs activity, but not that of {sup 137}Cs, showed a significant negative correlation with sampling depth (150-400 m) of GC fish; this strengthens our Fukushima fallout assumption. As a result, the Fukushima fallout in these sea areas only marginally enhanced (GC: 4%; BS: 0.1%) pre-Fukushima levels of individual dose rates received by human fish consumers; the addition was around 0.001 μSv following the consumption of 10 kg of fish per year, which is not expected to cause concern according to present guidelines for radiation protection.

  17. Derived concentration factors for caesium-137 in edible species of North Sea fish

    International Nuclear Information System (INIS)

    Steele, A.K.

    1990-01-01

    Concentration factor (CF=Bq kg -1 fillet/Bg kg -1 filtered sea water) values for 137 Cs in fillets of cod (Gadus morhua), haddock (Merlanogrammus aeglefinus), plaice (Pleuronectes platessa) and whiting (Merlangius merlangius), were derived from fish and filtered seawater concentrations. Samples were collected in twelve sampling boxes in the North Sea over an eight-year period - 1978-1985. The range of results with species, between species, and between surveys are discussed. Mean CF values of 92, 58, 39 and 150 were found in cod, haddock, plaice and whiting respectively. These support the International Atomic Energy Authority recommended CF value of 100 for fish in generalised dose assessments. (author)

  18. Radiation dose to Sri Lankan infants from Caesium-137 in contaminated milk

    International Nuclear Information System (INIS)

    Hewamanna, R.; Dias, M.P.

    1999-01-01

    The radiation dose to infants due to ingestion of milk containing the maximum limit of radioactivity in milk powder imported to Sri Lanka has been calculated. The radioactivity of Cs-137 was used as an index of fission products for setting radioactivity limits. The computation for milk powder was based on an average daily intake of 125 g by infants, (a critical group of population) during the first year after birth. The recommended dose commitment to the general public is 1 mSv/y. The maximum permissible limit of 20 Bq/kg of Cs-137 in milk powder as stipulated by the Atomic Energy Authority for milk powder imported to Sri Lanka would yield a dose equivalent of 12.6 micro seivert/y from Cs-137

  19. Iodine-129, Iodine-127 and Caesium-137 in the environment: soils from Germany and Chile

    International Nuclear Information System (INIS)

    Daraoui, A.; Michel, R.; Gorny, M.; Jakob, D.; Sachse, R.; Synal, H.-A.; Alfimov, V.

    2012-01-01

    Soil profiles from Bavaria in southern Germany and from Chile were analysed for 129 I by accelerator mass spectrometry (AMS), for 127 I by inductively coupled plasma mass spectrometry (ICP-MS), and for 137 Cs by gamma-spectrometry. The mean deposition density of 137 Cs in soils from Bavaria was (41 × 1.5 ±1 ) kBq m −2 (geometric mean and geometric standard deviation), originating mostly from the Chernobyl fall-out. The deposition density of 129 I in these soils was (109 × 1.5 ±1 ) mBq m −2 . The dominant sources of 129 I in Bavaria are, however, the reprocessing plants La Hague and Sellafield and not the Chernobyl fall-out. The 129 I/ 127 I isotopic ratios of the Bavarian soils were between 10 −7 and 10 −10 , i.e. 10 2 –10 5 times higher than the ratios observed for the samples from Chile. The 129 I integral deposition densities in Chile, Easter Island and Antarctica were between 0.3 mBq m −2 and 2 mBq m −2 . In these soils, the observed 129 I/ 127 I ratios were about 10 −12 . The soils from Chile allow the determination of the 129 I fall-out from the atmospheric nuclear weapons explosions undisturbed from contaminations due to releases from reprocessing plants. An upper limit of the integral 129 I deposition density of the atmospheric nuclear weapons explosions on the Southern Hemisphere (27°S) is about 1 mBq m −2 . Finally, the dependence of the migration behaviour of 137 Cs, 127 I and of 129 I on the soil properties is discussed. It turns out that there is a distinctly different behaviour of 127 I, 129 I, and 137 Cs in the soils exhibiting different sorption mechanisms for old and recent iodine as well as for 137 Cs. - Highlights: ► I-129 from European reprocessing plants drastically changed its natural abundances. ► We report here inventories of the Cs-137 and I-129 in Bavaria and Chile. ► The dominant sources of I-129 in Bavaria are the European reprocessing plants. ► The dominant sources of I-129 in Chile are the atmospheric nuclear test. ► I-129 and I-127 demonstrates the complex migration in the soil profiles.

  20. Selected radionuclides. Tritium, carbon-14, krypton-85, strontium-90, iodine, caesium 137, radon, plutonium

    International Nuclear Information System (INIS)

    1983-01-01

    The release of radioactive materials to the environment potentially exposes populations to ionizing radiation and increases the risk of incurring deleterious health effects. The associations of released amounts to effects establish the health criteria for radionuclides. This report provides background information in establishing such health criteria for 14 C, 85 Kr, 90 Sr, 137 Cs, Radon, Plutonium, Iodine and Tritium, including environmental behaviour, sources, transport to man and dosimetry. A brief summary of the general aspects of radiation effects and of radiation protection considerations is presented

  1. Monitoring the genetic health of persons in Goiania accidentally exposed to ionizing radiation from caesium-137

    Energy Technology Data Exchange (ETDEWEB)

    Da Cruz, A D; Glickman, B W [Centre for Environmental Health, Department of Biology, University of Victoria, Victoria, BC (Canada)

    1998-12-01

    This work describes the long term genetic monitoring of the Goiania population exposed to ionizing radiation from {sup 137}Cs, using cytogenetic and molecular endpoints. Cytogenetically, micronucleus frequencies differentiated groups exposed to different levels of radiation. Two molecular methods were employed: (1) the hprt clonal assay, involving in vitro selection of 6-thioguanine-resistant hprt mutant clones which were characterized at the molecular level using RT-PCR and genomic analysis. Ionizing radiation exposure initially elevated hprt mutation frequency which gradually diminished, so that no significant increase was observed four and a half years after original exposure. The spectrum of hprt mutations recovered from ten individuals exposed to relatively high doses of radiation revealed a fourfold increase in the frequency of A:T {yields} G:C transitions. The increase is consistent with the effects of ionizing radiation in prokaryotes and lower eukaryotes. Additionally, a twofold increase in the frequency of deletions was observed which may reflect radiation induced DNA strand breakage; (2) determination of microsatellite instability using fluorescent PCR and genomic DNA from mononuclear cells. The frequency distributions of somatic microsatellite alterations in exposed and non-exposed populations were not different. Our assay lacked sensitivity to discriminate between spontaneous and induced microsatellite instability and therefore, is not suitable for population monitoring. Finally, we estimated the risk associated with radiation exposure for the exposed Goiania population. The estimated genetic risk of dominant disorders in the first post-exposure generation was increased nearly twenty-fourfold. The risk of carcinogenesis was increased by a factor of 1.5. (author)

  2. Radioecological modelling of Polonium-210 and Caesium-137 in lichen-reindeer-man and top predators.

    Science.gov (United States)

    Persson, Bertil R R; Gjelsvik, Runhild; Holm, Elis

    2018-06-01

    This work deals with analysis and modelling of the radionuclides 210 Pb and 210 Po in the food-chain lichen-reindeer-man in addition to 210 Po and 137 Cs in top predators. By using the methods of Partial Least Square Regression (PLSR) the atmospheric deposition of 210 Pb and 210 Po is predicted at the sample locations. Dynamic modelling of the activity concentration with differential equations is fitted to the sample data. Reindeer lichen consumption, gastrointestinal absorption, organ distribution and elimination is derived from information in the literature. Dynamic modelling of transfer of 210 Pb and 210 Po to reindeer meat, liver and bone from lichen consumption, fitted well with data from Sweden and Finland from 1966 to 1971. The activity concentration of 210 Pb in the skeleton in man is modelled by using the results of studying the kinetics of lead in skeleton and blood in lead-workers after end of occupational exposure. The result of modelling 210 Pb and 210 Po activity in skeleton matched well with concentrations of 210 Pb and 210 Po in teeth from reindeer-breeders and autopsy bone samples in Finland. The results of 210 Po and 137 Cs in different tissues of wolf, wolverine and lynx previously published, are analysed with multivariate data processing methods such as Principal Component Analysis PCA, and modelled with the method of Projection to Latent Structures, PLS, or Partial Least Square Regression PLSR. Copyright © 2017 Elsevier Ltd. All rights reserved.

  3. Polonium-210 and Caesium-137 in lynx (Lynx lynx), wolverine (Gulo gulo) and wolves (Canis lupus).

    Science.gov (United States)

    Gjelsvik, Runhild; Holm, Elis; Kålås, John Atle; Persson, Bertil; Asbrink, Jessica

    2014-12-01

    Wolves, lynx and wolverines are on the top of the food-chain in northern Scandinavia and Finland. (210)Po and (137)Cs have been analysed in samples of liver, kidney and muscle from 28 wolves from Sweden. In addition blood samples were taken from 27 wolves. In 9 of the wolves, samples of muscle, liver and blood were analysed for (210)Po. Samples of liver and muscle were collected from 16 lynx and 16 wolverines from Norway. The liver samples were analysed for (210)Po and (137)Cs. Only (137)Cs analyses were carried out for the muscle samples. The wolves were collected during the winter 2010 and 2011, while the samples for lynx and wolverines were all from 2011. The activity concentrations of (210)Po in wolves were higher for liver (range 20-523 Bq kg(-1) d.w.) and kidney (range 24-942 Bq kg(-1) d.w.) than muscle (range 1-43 Bq kg(-1) d.w.) and blood (range 2-54 Bq kg(-1) d.w.). Activity ratios, (210)Po/(210)Pb, in wolf samples of muscle, liver and blood were in the ranges 2-77, 9-56 and 2-54. Using a wet weight ratio of 3.8 the maximal absorbed dose from (210)Po to wolf liver was estimated to 3500 μGy per year. Compared to wolf, the ranges of (210)Po in liver samples were lower in lynx (range 22-211 Bq kg(-1) d.w.) and wolverine (range16-160 Bq kg(-1) d.w.). Concentration of (137)Cs in wolf samples of muscle, liver, kidney and blood were in the ranges 70-8410 Bq kg(-1) d.w., 36-4050 Bq kg(-1) d.w., 31-3453 Bq kg(-1) d.w. and 4-959 Bq kg(-1) d.w., respectively. (137)Cs in lynx muscle and liver samples were in the ranges 44-13393 Bq kg(-1) d.w. and 125-10260 Bq kg(-1) d.w. The corresponding values for (137)Cs in wolverine were 22-3405 Bq kg(-1) d.w. for liver and 53-4780 Bq kg(-1) d.w. for muscle. The maximal absorbed dose from (137)Cs to lynx was estimated to 3000 μGy per year. Copyright © 2014 Elsevier Ltd. All rights reserved.

  4. Evolution of caesium 137 levels in coconut water and copra in french Polynesia, since 1967

    International Nuclear Information System (INIS)

    Kabis de Saint-Chamas, L.; Bablet, J.P.; Ducousso, R.; Arnould, C.

    1991-01-01

    Nuclear experiments have been carried out by France in french Polynesia since 1966. The tests were first atmospheric, they have been underground since 1975. The experiment monitoring programme includes monitoring of 137 Cs contents in coconuts from the whole french polynesian territory. The methodology is described and the results of the 2 589 samples collected for 1967 to 1988 are presented. The maximum content found since 1967 is 52 Bq.kg -1 for coconut water and 289 Bq.kg -1 for coconut copra. The decrease of 137 Cs content is constant without discontinuity, whatever the distance from the explosion sites. The committed dose equivalent from 137 Cs delivered by coconut water and copra consumption represents only a few microsieverts a year [fr

  5. Estimating sedimentation rates and sources in a partially urbanized catchment using caesium-137

    Science.gov (United States)

    Ormerod, L. M.

    1998-06-01

    While there has been increased interest in determining sedimentation rates and sources in agricultural and forested catchments in recent years, there have been few studies dealing with urbanized catchments. A study of sedimentation rates and sources within channel and floodplain deposits of a partially urbanized catchment has been undertaken using the 137Cs technique. Results for sedimentation rates showed no particular downstream pattern. This may be partially explained by underestimation of sedimentation rates at some sites by failure to sample the full 137Cs profile, floodplain erosion and deliberate removal of sediment. Evidence of lateral increases in net sedimentation rates with distance from the channel may be explained by increased floodplain erosion at sites closer to the channel and floodplain formation by lateral deposition. Potential sediment sources for the catchment were considered to be forest topsoil, subsurface material and sediments derived from urban areas, which were found to be predominantly subsurface material. Tracing techniques showed an increase in subsurface material for downstream sites, confirming expectations that subsurface material would increase in the downstream direction in response to the direct and indirect effects of urbanization.

  6. Uptake of caesium-137 from peat and compost mould by vegetables in a greenhouse experiment

    Energy Technology Data Exchange (ETDEWEB)

    Malm, J.; Uusi-Rauva, A.; Paakkola, O. (Helsinki Univ. (Finland). Faculty of Agriculture and Forestry); Rantavaara, A. (Finnish Centre for Radiation and Nuclear Safety (STUK), Helsinki (Finland))

    1991-01-01

    A pot experiment was conducted to study the root uptake of {sup 137} Cs by vegetables grown in peat and composite mould in a greenhouse. The {sup 137}Cs in the growing media originated from Chernobyl fallout. The vegetables were cucumber (Cucumis sativus L. var. Farbio VDP SF 76), tomato (Lycopersicon esculentum L. Var. Virosa), parsley (Petroselinum crispum A.W. Hill var. Non plus ultra), radish (Raphanus Sativus L. var. Nondan) and lettuce (Lactuca sativa L. var Atraktion). The effect of adding potassium to the peat was also studied. The transfer factors (activity in plant dry weight/activity in soil dry weight) varied from 0.66 to 1.8 for peat and from 0.060 to 0.19 for compost mould. Addition of potassium did not have any clear effect on the transfer factors. (Author).

  7. Variations of caesium isotope concentrations in air and fallout at Dalat, South Vietnam, 1986-1991

    International Nuclear Information System (INIS)

    Pham Zuy Hien; Nguyen Thanh Binh; Truong Y.; Vuong Thu Bac; Nguyen Trong Ngo.

    1993-01-01

    Monthly records of Cs-137 and Cs-134 concentrations in air and fallout at Dalat for the period 1986-1991 are presented and discussed. The concentration variations exhibit distinct maxima during December-January, when dry fallout dominated. These peaks are explained by the intrusion of more radioactive cold air masses from temperate northern latitudes during the development of large-scale anticyclones frequently observed in the most active winter monsoon period. High dry fallout velocities (about 10 cm/s) determined from this data clearly demonstrate one of the most relevant characteristics of cold air masses: behind the cold front, vertical air motion is descending

  8. Spatial distribution of caesium-137 in soil cover of background terrestrial ecosystems, Central European Russia

    Energy Technology Data Exchange (ETDEWEB)

    Paramonova, Tatiana A. [Radioecology and Ecotoxicology Department of Soil Science Faculty, Moscow State Lomonosov University, 119234 Moscow (Russian Federation); Shamshurina, Evgenia N. [Laboratory of soil erosion and fluvial processes of Geography Faculty, Moscow State Lomonosov University, 119234 Moscow (Russian Federation)

    2014-07-01

    ¹³⁷Cs - the main long-living anthropogenic radionuclide - arrived in mass at Russian terrestrial ecosystems after nuclear tests in the atmosphere in 1960-yy. and after Chernobyl accident in 1986 y., but in spite of a long period since these events soil cover contamination by ¹³⁷Cs is considered as extremely resistant due to its firmly fixation by soil solid matter and a long half-life of the radionuclide. Wide-scale investigation in maximal diversity of natural, semi-natural and anthropogenic landscapes of Central European Russia (more than 400 soils samples from Vologda, Yaroslavl, Ivanovo, Tver regions which are representative for the southern taiga zone) demonstrates that modern average specific activity of ¹³⁷Cs in the upper 15-cm layer of soil is 11±3 Bq/kg (contamination density 0.05±0.01 Ci/km²), that is fully ecologically acceptable. It is important that the average concentrations of ¹³⁷Cs in the soil cover of individual regions are close to each other. The most likely these average values are approximate assessment of background radioactive contamination of soils in central European Russia outside of the immediate Chernobyl trace. At the same time approximately 3% of soils are characterized by elevated ¹³⁷Cs content - 62-98 Bq/kg (0.24-0.43 Ci/km²), that indicates the presence of low radioactive spots on the territory and may be considered as local Chernobyl fallout. All of them attribute with forest soils which are commonly characterized by considerably more high accumulation of ¹³⁷Cs (18±5 Bq/kg, 0.06±0.01 Ci/km²) due to advanced absorbing surface of trees. Agricultural lands (plagued or under meadows) and soils of industrial plots with scarce vegetation contain only 6±2 Bq/kg (0.03±0.01 Ci/km²) of ¹³⁷Cs. About 84-92% of ¹³⁷Cs are concentrated in the upper 15-cm layer of natural soils or in Ap horizon of plagued soils, thus vertical migration of radionuclide is very slow in spite of ~30 years after Chernobyl accident. But it may by considerable lateral migration of ¹³⁷Cs in geochemically connected landscapes through the process of water erosion that leads to additional radionuclide accumulation in peat and foggy-podsolic soils of watershed depressions (migration coefficient 1.3). Thus, shallow depressions could be those 'critical' elements of the landscape with low-contrast areas of additional ¹³⁷Cs accumulation. Long-range transport of ¹³⁷Cs in moderate humid landscapes seems of little importance since alluvial soils and bottom sediments contain only 8±4 Bq/kg and 2±1 Bq/kg correspondingly. (authors)

  9. Modelling of caesium dynamics in the negative ion sources at BATMAN and ELISE

    Science.gov (United States)

    Mimo, A.; Wimmer, C.; Wünderlich, D.; Fantz, U.

    2017-08-01

    The knowledge of Cs dynamics in negative hydrogen ion sources is a primary issue to achieve the ITER requirements for the Neutral Beam Injection (NBI) systems, i.e. one hour operation with an accelerated ion current of 40 A of D- and a ratio between negative ions and co-extracted electrons below one. Production of negative ions is mostly achieved by conversion of hydrogen/deuterium atoms on a converter surface, which is caesiated in order to reduce the work function and increase the conversion efficiency. The understanding of the Cs transport and redistribution mechanism inside the source is necessary for the achievement of high performances. Cs dynamics was therefore investigated by means of numerical simulations performed with the Monte Carlo transport code CsFlow3D. Simulations of the prototype source (1/8 of the ITER NBI source size) have shown that the plasma distribution inside the source has the major effect on Cs dynamics during the pulse: asymmetry of the plasma parameters leads to asymmetry in Cs distribution in front of the plasma grid. The simulated time traces and the general simulation results are in agreement with the experimental measurements. Simulations performed for the ELISE testbed (half of the ITER NBI source size) have shown an effect of the vacuum phase time on the amount and stability of Cs during the pulse. The sputtering of Cs due to back-streaming ions was reproduced by the simulations and it is in agreement with the experimental observation: this can become a critical issue during long pulses, especially in case of continuous extraction as foreseen for ITER. These results and the acquired knowledge of Cs dynamics will be useful to have a better management of Cs and thus to reduce its consumption, in the direction of the demonstration fusion power plant DEMO.

  10. Manufacture and inspection of metal containers for the storage of waste contaminated with caesium-137

    International Nuclear Information System (INIS)

    Brito, M.J.D.; Moreira, M.S.

    1998-01-01

    Several stages are described of the design and manufacture of a prototype unit and 15 metal cylindrical containers for the storage of contaminated waste generated by the radiological accident of Goiania in 1987. The tasks involved technicians from the Nuclear Technology Development Centre (CDTN) of Belo Horizonte and the co-authors, who conducted inspections in the period between 10 March 1993 and 18 May 1993 at the foundry in Goiania. (author)

  11. Interfacial engineering of electron transport layer using Caesium Iodide for efficient and stable organic solar cells

    Science.gov (United States)

    Upama, Mushfika Baishakhi; Elumalai, Naveen Kumar; Mahmud, Md Arafat; Wright, Matthew; Wang, Dian; Xu, Cheng; Haque, Faiazul; Chan, Kah Howe; Uddin, Ashraf

    2017-09-01

    Polymer solar cells (PSCs) have gained immense research interest in the recent years predominantly due to low-cost, solution process-ability, and facile device fabrication. However, achieving high stability without compromising the power conversion efficiency (PCE) serves to be an important trade-off for commercialization. In line with this, we demonstrate the significance of incorporating a CsI/ZnO bilayer as electron transport layer (ETL) in the bulk heterojunction PSCs employing low band gap polymer (PTB7) and fullerene (PC71BM) as the photo-active layer. The devices with CsI/ZnO interlayer exhibited substantial enhancement of 800% and 12% in PCE when compared to the devices with pristine CsI and pristine ZnO as ETL, respectively. Furthermore, the UV and UV-ozone induced degradation studies revealed that the devices incorporating CsI/ZnO bilayer possess excellent decomposition stability (∼23% higher) over the devices with pristine ZnO counterparts. The incorporation of CsI between ITO and ZnO was found to favorably modify the energy-level alignment at the interface, contributing to the charge collection efficiency as well as protecting the adjacent light absorbing polymer layers from degradation. The mechanism behind the improvement in PCE and stability is analyzed using the electrochemical impedance spectroscopy and dark I-V characteristics.

  12. Does the Fukushima NPP disaster affect the caesium activity of North Atlantic Ocean fish?

    Science.gov (United States)

    Kanisch, G.; Aust, M.-O.

    2013-08-01

    Fillet samples of marine fish collected from the East/West Greenland currents (GC) and from the Baltic Sea (BS) have been investigated by gamma-ray spectrometry within the regular German monitoring programme. In samples of the second half of 2011, 134Cs traces have been detected that are suggested to originate from the Fukushima fallout that was deposited in March/April 2011 over the northern North Atlantic and accumulated by fish. The radionuclide 134Cs (half-life 2 yr) was indeed detected with quite small activities at about 0.0036 Bq kg-1 w.w. Existing box models describing the transport of Cs within seawater boxes of the northeast Atlantic allowed for estimation of 134Cs contributions from other sources, i.e. from the Chernobyl fallout and from discharges by the two major European nuclear reprocessing plants; both were negligible around Greenland, while for the Chernobyl fallout a small 134Cs background contribution to BS fish was estimated. Model results confirmed the level of 134C measured in BS fish and showed its maximum to have occurred in winter 2011/2012 followed by a continuous decrease. It was also determined that 134Cs activity, but not that of 134Cs, showed a significant negative correlation with sampling depth (150-400 m) of GC fish; this strengthens our Fukushima fallout assumption. As a result, the Fukushima fallout in these sea areas only marginally enhanced (GC: 4%; BS: 0.1%) pre-Fukushima levels of individual dose rates received by human fish consumers; the addition was around 0.001 μSv following the consumption of 10 kg of fish per year, which is not expected to cause concern according to present guidelines for radiation protection.

  13. Does the Fukushima NPP disaster affect the caesium activity of North Atlantic Ocean fish?

    Directory of Open Access Journals (Sweden)

    G. Kanisch

    2013-08-01

    Full Text Available Fillet samples of marine fish collected from the East/West Greenland currents (GC and from the Baltic Sea (BS have been investigated by gamma-ray spectrometry within the regular German monitoring programme. In samples of the second half of 2011, 134Cs traces have been detected that are suggested to originate from the Fukushima fallout that was deposited in March/April 2011 over the northern North Atlantic and accumulated by fish. The radionuclide 134Cs (half-life 2 yr was indeed detected with quite small activities at about 0.0036 Bq kg−1 w.w. Existing box models describing the transport of Cs within seawater boxes of the northeast Atlantic allowed for estimation of 134Cs contributions from other sources, i.e. from the Chernobyl fallout and from discharges by the two major European nuclear reprocessing plants; both were negligible around Greenland, while for the Chernobyl fallout a small 134Cs background contribution to BS fish was estimated. Model results confirmed the level of 134C measured in BS fish and showed its maximum to have occurred in winter 2011/2012 followed by a continuous decrease. It was also determined that 134Cs activity, but not that of 134Cs, showed a significant negative correlation with sampling depth (150–400 m of GC fish; this strengthens our Fukushima fallout assumption. As a result, the Fukushima fallout in these sea areas only marginally enhanced (GC: 4%; BS: 0.1% pre-Fukushima levels of individual dose rates received by human fish consumers; the addition was around 0.001 μSv following the consumption of 10 kg of fish per year, which is not expected to cause concern according to present guidelines for radiation protection.

  14. The effects of large scale processing on caesium leaching from cemented simulant sodium nitrate waste

    International Nuclear Information System (INIS)

    Lee, D.J.; Brown, D.J.

    1982-01-01

    The effects of large scale processing on the properties of cemented simulant sodium nitrate waste have been investigated. Leach tests have been performed on full-size drums, cores and laboratory samples of cement formulations containing Ordinary Portland Cement (OPC), Sulphate Resisting Portland Cement (SRPC) and a blended cement (90% ground granulated blast furnace slag/10% OPC). In addition, development of the cement hydration exotherms with time and the temperature distribution in 220 dm 3 samples have been followed. (author)

  15. The behaviour of caesium-137 in oxisols and in the Goiania soil

    International Nuclear Information System (INIS)

    Wasserman, M.A.

    1998-01-01

    The 137 Cs soil-to-plant transfer factors obtained in oxisols accidentally contaminated in Goiania and in artificially contaminated soils are found to be higher than those of soils in temperate climates. These differences are discussed in the light of pedology and geochemical partitioning. Tropical soil characteristics such as acidity, the low availability of nutritive elements and low content of 2:1 clay types seem to determine a high availability of 137 Cs. The results of sequential extraction showed 137 Cs weakly bound to soil components and underlines the importance of Fe oxides in the control of the 137 Cs in topical climates. (author)

  16. Radioactivity distribution of the fruit trees ascribable to radioactive fall our (4). Caesium content and its distribution in peach trees

    International Nuclear Information System (INIS)

    Takata, Daisuke; Yasunaga, Eriko; Sasaki, Haruo; Tanoi, Keitaro; Nakanishi, Tomoko M.; Oshita, Seiichi

    2012-01-01

    Movement and distribution of radiocaesium in peach tree was studied. The radiocaesium distributed on branches most, which branches were 1, 2 or 3 years old. With the observation of tissues of trunk, the highest radiocaesium concentration was measured at the bark, which was higher than that of soil surface. The radiocaesium concentration was drastically low in the wood part. However, the total amount of radiocaesium of wood was as the same level as that of the bark. About 20% of radiocaesium in the tree was estimated to be removed as fruits and leaves. (author)

  17. Estimating sediment and caesium-137 fluxes in the Ribble Estuary through time-series airborne remote sensing

    International Nuclear Information System (INIS)

    Wakefield, R.; Tyler, A.N.; McDonald, P.; Atkin, P.A.; Gleizon, P.; Gilvear, D.

    2011-01-01

    High spatial and temporal resolution airborne imagery were acquired for the Ribble Estuary, North West England in 1997 and 2003, to assess the application of time-series airborne remote sensing to quantify total suspended sediment and radionuclide fluxes during a flood and ebb tide sequence. Concomitant measurements of suspended particulate matter (SPM) and water column turbidity were obtained during the time-series image acquisition for the flood and ebb tide sequence on the 17th July 2003 to verify the assumption of a vertically well mixed estuary and thus justifying the vertical extrapolation of spatially integrated estimate of surface SPM. The 137 Cs activity concentrations were calculated from a relatively stable relationship between SPM and 137 Cs for the Ribble Estuary. Total estuary wide budgets of sediment and 137 Cs were obtained by combining the image-derived estimates of surface SPM and 137 Cs with estimates of water volume from a two-dimensional hydrodynamic model (VERSE) developed for the Ribble Estuary. These indicate that around 10,000 tonnes of sediment and 2.72 GBq of 137 Cs were deposited over the tidal sequence monitored in July 2003. This compared favourably with bed height elevation change estimated from field work. An uncertainty analysis on the total sediment and 137 Cs flux yielded a total budget of the order of 40% on the final estimate. The results represent a novel approach to providing a spatially integrated estimate of the total net sediment and radionuclide flux in an intertidal environment over a flood and ebb tide sequence. - Research highlights: → This paper provides a rare insight into the next flux of sediment and associated radionuclide loading into an estuary over and ebb and flood tide sequence. → The paper uses high temporal resolution airborne imagery coupled with concomitant sampling to convert total suspended sediment flux to 137 Cs loading. → For the estuary and date studied, it is estimate that an 10,000 tonnes of sediment and 2.72 GBq of 137 Cs are deposited into the estuary. → An uncertainty budget of about 40% on the final estimate is detailed.

  18. Literature study of the radiobiological parameters of Caesium-137 required for evaluating internal irradiation doses as a function of age

    International Nuclear Information System (INIS)

    Garnier, A.

    1968-01-01

    This document reassembles information published in scientific literature on radiobiological parameters of Cs-137, necessary for the estimate of the internal irradiation dose of man according to his age (during growth). The data are completed by a commented review of the mathematical models, proposed in order to value the irradiation doses from ingested cesium and the biological parameters. (author) [fr

  19. Trends in caesium activity concentrations in milk from agricultural and semi-natural environments after nuclear fallout

    International Nuclear Information System (INIS)

    Mueck, K.

    1995-12-01

    The radiocaesium contamination of milk and milk products is directly related to that in grass or hay and therefore the time trend to the effective half-life in these fodders. In the early phase the half-life in grass predominantly depends on effects such as dilution due to plant growth, translocation and weathering effects. The average effective half-life during this period (growing season) lies between 5 and 18 days. In upland pastures values of up to 25 days are observed. Studies performed on a great number of sites in particular countries after the Chernobyl accident showed half-lives for 137 Cs in grass from 7.9±1.5 d to 10.5±1.4 d for the period of May to July. An equivalent biological half-life for 131 I was observed. Only one measurement of half-lives in winter was performed up to now indicating a substantially longer value (50 d). No reliable data on effective half-lives at other periods of the year (late summer, fall) are available and would require further research. The long-term decline is determined by soil properties. Soils with low fixation capacity and low pH show higher aggregated transfer factors into milk than others. In certain semi-natural alpine pastures these factors remain high for years which cannot be explained by extreme soil properties only. Other reasons such as water logging, little dilution due to low plant growth, cycling of radionuclides within living and dead plant biomass and runoff effects have to be considered as main causes. A classification system for the long-term trend in Cs-availability to milk is proposed, but further research on the differences and possible measures with respect to seasonal variations and climatic conditions is required. (author)

  20. Transfer factor of caesium-137 in natural and agricultural grass ecosystems in the area of Plavsk radioactive spot, Russia

    Energy Technology Data Exchange (ETDEWEB)

    Paramonova, Tatiana A.; Machaeva, Ekaterina N. [Radioecology and Ecotoxicology Department of Soil Science Faculty, Lomonosov Moscow State University, 119234 Moscow (Russian Federation); Belyaev, Vladimir R. [Laboratory of soil erosion and fluvial processes of Geography Faculty, Lomonosov Moscow State University, 119234 Moscow (Russian Federation)

    2014-07-01

    Root uptake and translocation of ¹³⁷Cs from soil to plant is the key for estimation of general ecological situation and land use on radioactive contaminated territories. There are numerous researches concerning the relationship between the level of the radionuclide presence in soils and its accumulation in vegetation that usually describes as transfer factor (TF) for ¹³⁷Cs (the ratio of the specific ¹³⁷Cs activity in the plant tissue and the soil). But in most cases only edible organs or above-ground parts of plants are taken into account in evaluating TF. It is reasonable from the standpoint of practical use, but does not provide accurate information in the study of ¹³⁷Cs biogeochemical cycle features. The study of the ¹³⁷Cs root uptake from the radioactive contaminated chernozem soil and its distribution between above-ground and below-ground fractions of grass vegetation was conducted in the natural conditions on the territory of Plavsk radioactive spot (Tula region, Russia)~25 years after Chernobyl accident. The main crops of field rotation in this landscape (wheat, barley, potatoes, rape, maize) which occupy watersheds and slopes with arable chernozems contaminated at a level 460-670 Bq/kg (170-220 kBq/m²) and natural grassland ecosystems which occupy lower parts of slopes and flood plains with dry and wet meadows contaminated at a level 620-710 Bq/kg (210-250 kBq/m²) were examined. Total accumulation of ¹³⁷Cs in vegetation strongly depends on the level of soil radioactive contamination (correlation coefficient 0.87). So specific ¹³⁷Cs activity in vegetation of meadows (103-160 Bq/kg) in general more than one in agricultural crops (9-92 Bq/kg). Other reason may be the predominance of perennial herbs in natural meadows whereas agricultural systems contain annual crops. The values of ¹³⁷Cs TF in the studied ecosystems vary within a relatively narrow range: from 0.01 (rape) to 0.20 (wet meadow), that confirms the discrimination of the radionuclide root uptake. At the same time the distribution of ¹³⁷Cs between above-ground and below-ground fractions of plants in all observed cases is quite non-uniformly: below-ground parts of vegetation accumulate 3-5 times more than above-ground ones. An exception is potatoes agrocenosis where the TF values for different parts are almost identical, but below-ground fraction of potatoes consists of grater modified shoots, but no roots. There is a pronounceable difference in ¹³⁷Cs TF values for root tissues of various plant associations. The highest TF values in below-ground fraction are typical for vegetation with agricultural or wild cereals (0.15-0.26) having fibrous root system, the lowest TF values are characterized for rape agrocenosis (0.02) having stem root system. Thus, the major differences in the ¹³⁷Cs TF from contaminated soil to plant may be closely related to the features of the root system and the further translocation of the radionuclide into shoot, which requires quantitative account of ¹³⁷Cs accumulation not only in above-ground green parts, but also in roots. (authors)

  1. The uptake and storage of caesium and strontium by spring wheat - a modelling study based on a field experiment

    Energy Technology Data Exchange (ETDEWEB)

    Gaerdenaes, Annemieke I.; Linnea Berglund, S.; Bengtsson, Stefan B.; Rosen, Klas [Dept. of Soil and Environment, Swedish University of Agricultural Sciences (SLU), P.O. Box 7001, 750 07 Uppsala (Sweden)

    2014-07-01

    The aim was to model, quantify, and analyse the dynamics of uptake (foliar and root) and grain storage of wet-deposited radionuclides by a growing crop. The dynamic trace element model, Tracey, for terrestrial ecosystems was used after extension with descriptions for contamination by wet-deposition, interception, and foliar uptake. Tracey contains two alternative root uptake descriptions, one driven by transpiration and one by growth. Radionuclide fluxes were assumed proportional to the corresponding water or carbon fluxes in the soil-plant-atmosphere system, simulated with the CoupModel. The extended Tracey was calibrated against data from the wet-deposition experiment at Ultuna, central Sweden. {sup 134}Cs and {sup 85}Sr were deposited on spring wheat at six growth stages in 2010 and 2011. The sensitivity for different radionuclide, plant, and soil properties were assessed by Monte Carlo simulations using the sensitivity toolbox Eikos. One thousand simulations were made for each of the 48 scenarios (2 radionuclides, 2 root uptake approaches, 6 deposition treatments, 2 years). The simulated dynamics of grains' storage of radionuclides were accepted if the simulated values were within the 95% confidence interval of the measured values at all available samplings of a deposition treatment. A ten percentage of all {sup 134}Cs and {sup 85}Sr simulations were accepted. Highest percentage of accepted simulations was found for the scenarios with deposition shortly before harvest, indicating that the added model descriptions of deposition and interception performed well. The model mimicked well that the grain storage of radionuclides increased exponentially the later in the growing season the deposition took place; the storage of radionuclides when deposited at full ripening was 250 times higher than the storage when deposition took place at tillering. The model results confirmed that foliar uptake i.e. direct atmosphere-plant transfer, fully dominates total plant uptake when deposition takes place during the growing season. The estimated accumulated foliar uptake formed on average 99% of the Cs and 93% of Sr total plant uptake. We identified the governing factors of radionuclide storage in grains and how they varied with growth stage; the stem and leaves fixation rates dominate before flowering; the flowers/grain fixation rates dominate between flowering and ripening; and the interception retention capacity of the grains dominates from full ripening. We conclude that Tracey can accurately simulate the storage dynamics of radionuclides in plant parts that are a major ingredient in human food. We showed the dependency of the storage dynamics on the local weather, growth and soil conditions. The model and results can be used to tailor counter-measures to local conditions in the case of a radioactive deposition and to improve preparedness for radioactive deposition on growing crops. (authors)

  2. Caesium-137 and strontium-90 in the food chains: model development using fallout data. [Pasture-cow-milk pathway

    Energy Technology Data Exchange (ETDEWEB)

    Haywood, S M [National Radiological Protection Board, Harwell (UK)

    1980-11-01

    The development of the models for the movement of /sup 137/Cs and /sup 90/Sr in the pasture-cow-milk pathway is briefly discussed. Using recorded deposition rates of these radionuclides as input to the basic model, it was found that the models for /sup 137/Cs and /sup 90/Sr in their initial form were found to predict higher levels of activity in milk than those recorded. The predicted contributions of the processes of root uptake into pasture grass and the resuspension of deposited activity on to pasture surfaces were shown to be responsible for much of the overestimation. Following a re-evaluation of all transfer parameters, major improvements in the quality of fit between the model predictions and measured levels of /sup 137/Cs and /sup 90/Sr in milk were obtained.

  3. The transfer of strontium-90 and caesium-137 to milk in a dairy herd grazing near a major nuclear installation

    Energy Technology Data Exchange (ETDEWEB)

    Sumerling, T J; Dodd, N J; Green, N

    1984-03-01

    A field investigation of the transfer of artificially produced radionuclides in the pasture--cow--milk pathway has been made at a farm close to the nuclear fuel reprocessing installation at Sellafield on the north-west coast of England. This paper reports results from analyses of samples collected during 1981, reports transfers coefficients for /sup 90/Sr and /sup 137/Cs from various types of feed to milk, and discusses factors that affect the transfer of these radionuclides. It is shown that during 1981 a large proportion of the /sup 90/Sr and /sup 137/Cs consumed by cattle grazing near Sellafield was derived from activity deposited in previous years. Transfer coefficients to milk, Fm, have been derived which are within the ranges of those observed in tracer and fallout studies. There are significant seasonal changes in transfer. For /sup 90/Sr, values of Fm between 9 X 10(-4)d 1(-1) and 4 X 10(-3)d 1(-1) have been obtained. It is concluded that this large range arises because daily intakes of /sup 90/Sr by the herd during the winter months are lower (by a factor of about 3) than intakes during the summer months and that the concentration of /sup 90/Sr in milk is not in equilibrium with intake, that is, the concentration of /sup 90/Sr in milk is maintained both by recent intakes and by remobilisation of activity that has been accumulated in bone from earlier intakes. For /sup 137/Cs, values of Fm between 3 X 10(-3)d 1(-1) and 9 X 10(-3)d 1(-1) have been obtained. It is concluded that this range most probably occurs because during the summer months, when the cows are grazing, a substantial proportion of the /sup 137/Cs intake is associated with soil on the surface of herbage and that, in this form, the /sup 137/Cs is less available for uptake from the digestive tract of the cows.

  4. Modelling of long-term behaviour of caesium and strontium radionuclides in the Arctic environment and human exposure

    International Nuclear Information System (INIS)

    Golikov, Vladislav; Logacheva, Irina; Bruk, Gennadi; Shutov, Vladimir; Balonov, Mikhail; Strand, Per; Borghuis, Sander; Howard, Brenda; Wright, Simon

    2004-01-01

    In this paper a compartment model of the highly vulnerable Arctic terrestrial food chain 'lichen-reindeer-man' is outlined. Based upon an analysis of measured 137 Cs and 90 Sr contents in lichen and reindeer meat from 1961 up to 2001, site specific model parameters for two regions in north-western Arctic Russia and for Kautokeino municipality in Arctic Norway have been determined. The dynamics of radionuclide activity concentrations in the 'lichen-reindeer-man' food chain for all areas was satisfactorily described by a double exponential function with short-term and long-term effective ecological half-lives between 1-2 and 10-12 years, respectively, for both 137 Cs and 90 Sr. Using parameter values derived from the model, life-time internal effective doses due to consumption of reindeer meat by reindeer-breeders after an assumed single pulse deposit of 1 kBq m -2 of 137 Cs were estimated to be 11.4 mSv (Kola Peninsula), 5 mSv (Nenets Autonomous Area), and 2 mSv (Kautokeino, Norway). Differences in vulnerability to radiocaesium deposition were due to differences in transfer between lichen and reindeer and in diet between the three regions

  5. Modern parameters of caesium-137 root uptake in natural and agricultural grass ecosystems of contaminated post-Chernobyl landscape, Russia

    Directory of Open Access Journals (Sweden)

    Tatiana Paramonova

    2015-01-01

    Full Text Available The estimation of modern parameters of 137Cs root uptake was conducted in natural meadow and agricultural ecosystems of post-Chernobyl landscapes of Tula region. The agrosystems with main crops of field rotation (barley, potatoes, rape, maize occupying watersheds and slopes with arable chernozems are contaminated at a level 460-670 Bq/kg (4.7-6.0 Ci/km2; natural meadow ecosystems occupying lower parts of slopes and floodplains are contaminated at a level 620-710 Bq/kg (5.8-7.6 Ci/km2. In the arable soils 137Cs uniformly distributed to a depth of Ap horizon (20-30 cm of thickness, while in meadow soils 70-80% of the radionuclide is concentrated within the top Ad horizon (9-13 cm of thickness. These topsoil layer accords with rhizosphere zone, where >80-90% of plant roots are concentrated, and from which 137Cs is mostly consumed by vegetation. Total amount of 137Cs root uptake depends on the level of soil radioactive contamination (correlation coefficient 0.61. So 137Cs activity in meadow vegetation (103-160 Bq/kg is generally more than one in agricultural vegetation (9-92 Bq/kg. The values of 137Cs transfer factor in the studied ecosystems vary from 0.01 (rape to 0.20 (wet meadow, that confirms the discrimination of the radionuclide’s root uptake. The larger are the volume of roots and their absorbing surface, the higher are the values of transfer factor from soil to plant (correlation coefficients 0.71 and 0.64 respectively. 137Cs translocation from roots to shoots is also determined by biological features of plants. At the same level of soil contamination above-ground parts of meadow herbs accumulate more 137Cs than Gramineae species, and in agrosystems above-ground parts of weeds concentrate more 137Cs than cultivated cereals. Thus, the level of soil radioactive pollution and biological features of plants are determinants in the process of 137Cs root uptake and translocation and should be considered in land use policy.

  6. Removal of radioactive caesium from low level radioactive waste (LLW) streams using cobalt ferrocyanide impregnated organic anion exchanger

    Energy Technology Data Exchange (ETDEWEB)

    Valsala, T.P., E-mail: tpvalsala@yahoo.co.in [Waste Management Division, Bhabha Atomic Research Centre, Trombay 400 085 (India); Roy, S.C. [PREFRE Division, Bhabha Atomic Research Centre, Tarapur 401 502 (India); Shah, J.G. [Back End Technology Division, Bhabha Atomic Research Centre, Trombay 400 085 (India); Gabriel, J.; Raj, Kanwar [Waste Management Division, Bhabha Atomic Research Centre, Trombay 400 085 (India); Venugopal, V. [Radiochemistry Division, Bhabha Atomic Research Centre, Trombay 400 085 (India)

    2009-07-30

    The volumes of low level waste (LLW) generated during the operation of nuclear reactor are very high and require a concentration step before suitable matrix fixation. The volume reduction (concentration) is achieved either by co-precipitating technique or by the use of highly selective sorbents and ion exchange materials. The present study details the preparation of cobalt ferrocyanide impregnated into anion exchange resin and its evaluation with respect to removal of Cs in LLW streams both in column mode and batch mode operations. The Kd values of the prepared exchanger materials were found to be very good in actual reactor LLW solutions also. It was observed that the exchanger performed very well in the pH range of 3-9. A batch size of 6 g l{sup -1} of the exchanger was enough to give satisfactory decontamination for Cs in actual reactor LLW streams. The lab scale and pilot plant scale performance of the exchanger material in both batch mode and column mode operations was very good.

  7. Caesium and Plutonium Isotopes as Tracers of Various Events in Sediment Records in the Bay of Toulon (Northwestern Mediterranean Sea)

    Energy Technology Data Exchange (ETDEWEB)

    Duffa, C.; Arnaud, M.; Charmasson, S.; Thebault, H. [Institut de Radioprotection et de Surete Nucleaire, DEI/SESURE/LERCM, La Seyne sur Mer (France)

    2013-07-15

    Located along the French Mediterranean coast, the Toulon bay has a specific configuration with two basins. The shallow one is a semi-enclosed basin (Petite Rade) with complex hydrodynamic conditions that contribute to fine sedimentation. The open sea basin, separated from the first one by a long sea wall, receives different anthropogenic inputs. Surface and core sediment sampling cruises took place in 2001 and 2008, in order to study radionuclide spatial dispersion and sediment accumulation. {sup 137}Cs values are statistically higher in the 'Petite Rade' than in the open basin. {sup 239+240}Pu levels range from 0.7 to 2.6 Bq/kg dry weight in surface sediments, up to 6 times higher than elsewhere in Mediterranean coastal areas not influenced by riverine inputs. Plutonium activity ratios ({sup 238}Pu/{sup 239+240}Pu and {sup 239}Pu/{sup 240}Pu) labelled atmospheric nuclear weapon testing. Regarding the long cores, the highest plutonium activities, measured by alpha counting and ICP-MS, concern the first ten centimetres with a maximum value of 3.5 Bq/kg dry weight in {sup 239+240}Pu. (author)

  8. Calculation of transfer factors for the transfer of caesium-137 from feedingstuffs to the meat of farm animals

    International Nuclear Information System (INIS)

    Mirna, A.

    1979-01-01

    To calculate the radiation exposure of the population in the surroundings of nuclear technical plants, the knowledge of the transfer of emitted radionuclides to plants, animals, and food is an essential precondition. Recent data from the literature about transfer factors (food/meat) of cesium-137 (Cs-137) for calves, cattle, and pigs have revealed considerable differences between the species mentioned and the value in the 'general calculation fundaments for the determination of radiation exposure by emission of radioactive substances with waste air' (12). In the FR of Germany mainly pork is eaten, therefore, it is interesting to know if the transfer of Cs-137 in the individual animal species is so far the same that it is justified to only use the exposure path grass-cattle for calculation. The values presented here have suggested for the transfer of fall-out Cs-137 from the food into the meat a value, on an average, six times as high as had been assumed up to day. In pork meat, there was even an increase by 2 tenth powers. (orig.) [de

  9. Observation of the spin-orbit activated interchannel coupling in the 3d photoionization of caesium atoms

    International Nuclear Information System (INIS)

    Farrokhpour, H; Alagia, M; Amusia, M Ya

    2006-01-01

    The ionization cross-section of the 3d spin-orbit components of the Cs atom has been measured from about 12 to 70 eV above their respective thresholds. The measured relative ionization cross-section of the 3d 5/2 channel exhibits a pronounced minimum above threshold followed by a second maximum near the 3d 3/2 ionization onset and thus qualitatively confirms the theoretical predictions of a spin-orbit activated interchannel coupling (Amusia et al 2002 Phys. Rev. Lett 88 093002)

  10. Observation of the spin-orbit activated interchannel coupling in the 3d photoionization of caesium atoms

    Energy Technology Data Exchange (ETDEWEB)

    Farrokhpour, H [Chemistry Department, Isfahan University of Technology, Isfahan 84154 (Iran, Islamic Republic of); Abdus Salam International Centre for Theoretical Physics, I-34014 Trieste (Italy); Alagia, M [CNR-ISMN Sez.Roma1, P.le A Moro 5, I-00185 Rome (Italy) and CNR-Lab. Naz. TASC-INFM, Gas Phase Beamline at Elettra, Area Science Park, I-34012 Basovizza, Trieste (Italy); Amusia, M Ya [Racah Institute of Physics, Hebrew University, Jerusalem 91904 (Israel); A F Ioffe Physical-Technical Institute, St Petersburg 194021 (Russian Federation)] (and others)

    2006-02-21

    The ionization cross-section of the 3d spin-orbit components of the Cs atom has been measured from about 12 to 70 eV above their respective thresholds. The measured relative ionization cross-section of the 3d{sub 5/2} channel exhibits a pronounced minimum above threshold followed by a second maximum near the 3d{sub 3/2} ionization onset and thus qualitatively confirms the theoretical predictions of a spin-orbit activated interchannel coupling (Amusia et al 2002 Phys. Rev. Lett 88 093002)

  11. Performance evaluation of of caesium, iodine, strontium and ruthenium isotopes in urban areas after contamination by accidental release

    International Nuclear Information System (INIS)

    Vetere, Maria Ines de Carvalho

    2002-03-01

    The exposures of urban populations to the radiation derived from the deposition, after accidental atmospheric releases, of I37 Cs, 134 Cs, 129 I, 131 I, 133 I, 89 Sr, l03 Ru and 106 Ru were assessed, using the integrated system for the evaluation of environmental radiological impact in emergency situations (SIEM), developed by the Instituto de Radioprotecao e Dosimetria (IRD) / Comissao Nacional de Energia Nuclear (CNEN). These radionuclides are fission products likely to be emitted in the occurrence of severe nuclear reactor accidents. Their environmental behaviour in urban areas, due to their deposition in soil, in urban surfaces and in vegetable-garden food products, such as leafy and non-leafy vegetables, were analyzed, and dose assessments at the short, medium and long terms were performed, with and without the application of protective measures for reduction of doses. Simulations of unitary initial deposition for each radionuclide and of two different potential accidents involving pressurized water reactors (PWR), with different source terms and distinct deposition for each radionuclide, were performed. Results were analyzed on the basis of the relative relevance of radionuclides and pathways for the exposure of members of the public, as a function of age and time after the release. It was also performed an assessment of the effectiveness of protective measures as a function of the moment of their implementation. (author)

  12. Field investigations of the transfer of caesium-137 in the pasture-cow-milk pathway in West Cumbria

    International Nuclear Information System (INIS)

    Sumerling, T.J.

    1983-01-01

    Routine discharges from the nuclear fuel reprocessing installation at Sellafield provide an opportunity to study the behaviour in the environment of several artificially produced radionuclides. Two investigations of the transfer of radionuclides in the pasture-cow-milk pathway are described. The uptake of 137 Cs by cattle grazing sea-washed pasture near Ravenglass has been investigated by in vivo measurements of the animals. A very low coefficient of transfer from feed to meat was estimated. The transfer of several radionuclides, notably 90 Sr, 137 Cs, 239 Pu and 241 Am, is being studied at a dairy farm near Sellafield. Preliminary results for 137 Cs are reported and are found to be in reasonable agreement with model predictions. (author)

  13. The uptake and transfer of caesium-137, strontium-90 and zinc-65 from soil to food crops in tropical environment

    International Nuclear Information System (INIS)

    Sachdev, P.; Sachdev, M.S.; Deb, D.L.

    1998-01-01

    The soil to plant transfer factors (TF) of 137 Cs, 90 Sr and 65 Zn were determined for two crops, pearlmillet (Pennisetum typhoides) and sorghum (Sorghum vulgare) under irrigated conditions in greenhouse and in natural conditions of rain in field. The accumulation of 137 Cs was almost doubled when the soil contamination level was doubled. Under the field conditions, 137 Cs concentration in both pearlmillet and sorghum grains as well as straw was nearly four times more at a higher level of soil contamination (148 kBq/kg soil) compared to that at a lower level of 74 kBq/kg soil. 90 Sr absorption by both the crops was nearly 50 to 100 times more compared to 137 Cs under identical conditions of crop growth and soil contamination. 65 Zn concentration was higher in pearlmillet grains than in straw portions, whereas in sorghum it was otherwise. The TF values for 137 Cs decreased nearly ten fold in the second year both under field and pot culture conditions, while those for 90 Sr reduced by half and for 65 Zn by about five times. Under irrigated conditions in field the transfer factors for 137 Cs were nearly four times larger both for pearlmillet and sorghum (1996 experiment) and for 90 Sr more than two times, compared to those under rain fed conditions obtained in 1994. (author)

  14. A mouse model of cytogenetic analysis to evaluate caesium137 radiation dose exposure and contamination level in lymphocytes

    Energy Technology Data Exchange (ETDEWEB)

    Roch-Lefevre, Sandrine; Martin-Bodiot, Cecile; Gregoire, Eric; Roy, Laurence [Institut de Radioprotection et de Surete Nucleaire (IRSN), Laboratoire de Dosimetrie Biologique (PRP-HOM/SRBE/LDB), Fontenay aux Roses Cedex (France); Desbree, Aurelie [Institut de Radioprotection et de Surete Nucleaire (IRSN), PRP-HOM/SDI, Laboratoire d' Evaluation de la Dose Interne, Fontenay aux Roses Cedex (France); Barquinero, Joan Francesc [Institut de Radioprotection et de Surete Nucleaire (IRSN), Laboratoire de Dosimetrie Biologique (PRP-HOM/SRBE/LDB), Fontenay aux Roses Cedex (France); Universitat Autonoma de Barcelona, Unitat d' Antropologia Biologica, Departament de Biologia Animal, Biologia Vegetal i Ecologia, Bellaterra (Spain)

    2016-03-15

    In case of external overexposure to ionizing radiation, an estimation of its genotoxic effects on exposed individuals can be made retrospectively by the measurement of radiation-induced chromosome aberrations on circulating lymphocytes. Compared with external irradiation, intakes of radionuclides may, however, lead to specific features influencing dose distribution at the scale of body, of tissue or even of cell. Therefore, in case of internal contamination by radionuclides, experimental studies, particularly using animal models, are required to better understand mechanisms of their genotoxic effects and to better estimate the absorbed dose. The present study was designed to evaluate a cytogenetic method in mouse peripheral blood lymphocytes that would allow determination of yields and complexities of chromosome aberrations after low-dose rate exposure to {sup 137}Cs delivered in vitro either by irradiation or by contamination. By using M-FISH analysis, we compared the low-dose rate responses observed in mouse to the high-dose rate responses observed both in mouse and in human. Promising similarities between the two species in the relative biological effect evaluation show that our cytogenetic model established in mouse might be useful to evaluate various radiation exposures, particularly relevant in case of intakes of radionuclides. (orig.)

  15. A study of the properties of hexacyanoferrate sorbents and their use for sorption of caesium and strontium

    International Nuclear Information System (INIS)

    Kareta, V.I.; Grivkova, A.I.; Artemova, T.N.; Mizina, L.I.; Krasavina, E.P.

    1997-01-01

    A method of deposition of zinc, copper, and nickel hexacyanaferrates on silica-containing substrate (clinoptilolite) has been developed to produce mechanically strong sorbents for cesium and strontium separation from solutions of different compositions. The modification of clinoptilolite increases its sorption capacity for both cesium and strontium. Sorption behaviour of radionuclides was studied both in static and kinetic conditions. (author). 21 refs, 5 figs, 7 tabs

  16. Caesium releases under the form of silicon micro-balls during the Fukushima-Daiichi accident. Information note

    International Nuclear Information System (INIS)

    2016-01-01

    After having outlined that the most part (89 per cent) of radioactive cesium released in the atmosphere during the Fukushima accident was made under the form of silicon micro-balls which were more irradiating than other aerosols marked by cesium radioactive isotopes, this note first discusses whether these silicon micro-balls containing radioactive cesium were resulting from a specific phase of atmospheric release. It discusses the nature of these micro-balls, and discusses whether it is possible to quantitatively assess the contribution of these micro-balls to global releases and deposits. It discusses how these micro-balls could have formed, whether their formation can be associated with a specific phase of reactor degradation or with the degradation of a specific reactor. It discusses whether a specific behaviour of these micro-balls can be expected in the environment, and their possible impacts on radiological consequences

  17. A note on the entropy of mixing of liquid sodium-caesium and other binary alkali alloys

    International Nuclear Information System (INIS)

    Alonso, J.A.; Gallego, L.J.

    1985-01-01

    The entropy of formation of Na-Cs liquid alloys. ΔS, is nearly ideal. This is surprising considering that the ratio between the pure metal volumes is about 3.0. In this Letter it is shown by means of a density functional calculation that the ratio between the effective volumes in the liquid alloy changes to nearly 1.5. This ratio, used in conjunction with Flory's formula for the entropy of mixing, allows quite accurate reproduction of the ideal behaviour of ΔS. It is also shown that this feature of the ratios of atomic volumes is not exclusive to Na-Cs but is common to all the family of binary liquid alkali alloys. (author)

  18. Chemical treatments to reduce the transfer of caesium radioisotopes to the human foodchain after a serious nuclear accident

    International Nuclear Information System (INIS)

    Silva, S.

    1993-01-01

    The aim of the project is to produce a reduction of the transfer factors of radiocesium in plants, milk and meat owing to a deposition of radioactive products following a severe nuclear accident. The project includes two distinct working departments. The first studies the possibility to reduce the translocation of radiocesium from the areal parts to the edible products of crops. The second studies the possibility to reduce the radiocesium in the milk and in the meat as a consequence of the feeding with contaminated fodder. (R.P.) 4 refs., 5 figs., 7 tabs

  19. Caesium-137 root uptake by agricultural and wild crops in post-Chernobyl landscape: the possibilities for phytoremediation?

    Science.gov (United States)

    Paramonova, Tatiana; Shamshurina, Eugenia; Komissarova, Olga; Belyaev, Vladimir

    2015-04-01

    In spite of long term period after Chernobyl fallout (≈25 years after the accident) the level of Cs-137 in soils of contaminated landscapes remains several times more than radiation safety standard (= 37 kBq/m2). In particular, within the area of Plavsk radioactive hot spot (Tula region, Russia) current Cs-137 activities in soil are 460-500 Bq/kg (170-200 kBq/m2) on watershed, 580-680 Bq/kg (200-220 kBq/m2) in arable lower parts of slopes and 620-710 Bq/kg (210-280 kBq/m2) in untilled foots of slopes and river floodplains. To estimate the process of Cs-137 root uptake and incorporation of the radionuclide in plant tissues 6 agricultural crops of typical field rotation (spring barley, maize, summer rape, galega, potatoes, amaranth) as well as natural ecosystems of dry and wet meadows were selected for the detailed study. Total bioproductivity of agricultural crops varies between 1.7-3.9 kg/m2, natural grass ecosystems - 1.9-2.2 g/m2, and is obviously unaffected by radioactive land contamination. At the same time Cs-137 activity in total biomass slightly increases with Cs-137 activity in soil (correlation coefficient r=0.45) and with total biomass (correlation coefficient r=0.51) in the row: rape (5 Bq/kg) cereals that are true accumulators of Cs-137 seem to be useless for phytoremediation purposes, as 86-97% of the radionuclide inventory is associated with roots and remains in soil after cutting of aboveground parts. On the other hand, galega and amaranth could be considered as agricultural crops potentially being used for phytoremediation, since 87-93% of Cs-137 inventory is located in shoots. Potatoes having rather high aboveground biomass and easily removed from soil underground part could be also used for phytoremediation. However, it should be clearly understood that in total Cs-137 inventory in "soil-plant" system the annual amount of the radionuclide's consumption (that may be alienated when harvesting) is less than 0.01%, while the rate of Cs-137 radioactive decay is estimated as about 2% per year. Study was conducted with the support from the Russian Foundation for Basic Research (project no. 14-05-00903).

  20. Mobility of superficially applied caesium-134 and strontium-85 in apple branches under precipitation-free conditions

    International Nuclear Information System (INIS)

    Bengtsson, G.B.

    1992-01-01

    The recovery of superficially applied 134 Cs + and 85 Sr 2+ in apple branches protected from precipitation decreased with time. Translocation of 134 Cs to uncontaminated branches declined rapidly with the distance from the contaminated branches. Extensive translocation of 134 Cs from foliage to fruits occurred within the same branch: after 84 d, 50% of the recovered activity was found in fruits and most of it in the edible part (excluding peel). On the other hand, 85 Sr was less mobile and in virtually all fruit 85 Sr was in the peel. Rinsing leaves removed 30% of both radionuclides 1 d after contamination and decreasing fractions later on. Rinsing fruits removed up to 62% of the peel radionuclides. Further rinses and washes (plus detergent) of fruits showed that 134 Cs had the same distribution in the outer skin as 85 Sr and that the ratio of the two nuclides was close to the ratio in the contamination solution. This indicates that apple skin is a barrier not only to 85 Sr, but probably also to 134 Cs. Unaccounted for disappearance of radioactivity from fruits and leaves could have been a result to field losses of small superficial particles. (author)

  1. Studies of environmental radioactivity in Cumbria. Part 4 Caesium-137 and plutonium in soils of Cumbria and the Isle of Man

    International Nuclear Information System (INIS)

    Cawse, P.A.

    1980-08-01

    A network of soil sampling sites covering an area of some 2500 km 2 in Cumbria and the whole of the Isle of Man was selected and sampled in 1978. Soils from permanent grassland, coniferous woodland and deciduous woodland were examined, to a depth of 30 cm. The spatial distribution of sampling points is based on a grid of 10 km side. The objective of the study is to provide information on the integrated deposition of Cs-137, Pu-239+240 and Pu-238 from the atmosphere, and to determine the distribution of possible emissions from the nuclear establishment at Windscale in the presence of radioactivity deposited from nuclear weapons fallout, that is superimposed upon the natural background of radioactivity in soil. Results from soil samples collected in 1978 in Cumbria and the Isle of Man are compared with the average integrated deposition for UK soils from nuclear fallout. In the Isle of Man no radioactivity is observed in excess of nuclear weapons fallout, but in Cumbria excess levels of plutonium are detected in coastal lowland areas under permanent grassland probably due to the transport of radioactive material from sea to land. At three sampling sites on grassland and woodland within 2.3 km of the Windscale stacks, the excess plutonium and Cs-137 in soil could be attributed mainly to atmospheric discharges from Windscale. The observed deposition of radioactivity has little radiological significance, based on assessment of risk by inhalation of soil dust that contains plutonium. (author)

  2. Postmortal changes of the elemental composition of autopsy specimens: variations of caesium, cobalt and selenium in rat liver studied by instrumental neutron activation analysis

    International Nuclear Information System (INIS)

    Iyengar, G.V.; Kasperek, K.; Feinendegen, L.E.

    1982-01-01

    Using rat liver as an example, the implications of postmortal changes such as cell swelling, imbibition and autolysis on the elemental composition of body organs were studied. Of the three elements investigated in this part of the experiment, concentration of Co increased from about +50 per cent to +120 per cent of control in all groups retained at room temperature and the content of Co rose by about 95 per cent; Cs increased less extensively than Co in all groups at room temperature; Se values showed up to 50 per cent increase in concentration only and there was no change in content. The changes were less marked for all the three elements at -15 deg C. (author)

  3. Investigating the gas phase emitter effect of caesium and cerium in ceramic metal halide lamps in dependence on the operating frequency

    Energy Technology Data Exchange (ETDEWEB)

    Ruhrmann, C; Westermeier, M; Bergner, A; Awakowicz, P; Mentel, J [Ruhr University Bochum, Electrical Engineering and Plasma Technology, D-44780 Bochum (Germany); Luijks, G M J F, E-mail: juergen.mentel@ruhr-uni-bochum.de [Philips Lighting, GBU HID, PO box 80020, 5600JM Eindhoven (Netherlands)

    2011-09-07

    The work function and with it the temperature of tungsten electrodes in HID lamps can be lowered and the lifetime of lamps increased by the gas phase emitter effect. A determination of the emitter effect of Cs and Ce is performed by phase resolved measurements of the electrode tip temperature T{sub tip}({psi}), plasma temperature T{sub pl}({psi}) and particle densities N({psi}) by means of pyrometric, optical emission and broadband absorption spectroscopy in dependence on the operating frequency. The investigated HID lamps are ceramic metal halide lamps with transparent discharge vessels made of YAG, filled with a buffer gas consisting of Ar, Kr and predominantly Hg and seeded with CsI or CeI{sub 3}. In the YAG lamp seeded with CsI and CeI{sub 3} as well as in a YAG lamp seeded with DyI{sub 3} (corresponding results can be found in a preceding paper) a gas phase emitter effect is observed in the cathodic phase due to a Cs, Ce or Dy ion current. In the YAG lamp seeded with CsI the phase averaged coverage of the electrode surface with emitter atoms decreases and the electrode temperature rises with increasing frequency, whereas the emitter effect of Ce and Dy is extended to the anodic phase, which leads to a decreased average temperature T{sub tip}({psi}) with increasing frequency. This different behaviour of the averaged values of T{sub tip}({psi}) for increasing frequency is caused by the differing adsorption energies E{sub a} of the respective emitter materials. In spite of the influence of E{sub a} on the coverage of the electrode with emitter atoms, the cathodic gas phase emitter effect produces in the YAG lamps seeded with CsI, CeI{sub 3} and DyI{sub 3} a general reduction in the electrode tip temperature T{sub tip}({psi}) in comparison with a YAG lamp with Hg filling only.

  4. Final report on a field study of soil-to-plant transfer radioactive caesium, strontium and zinc in Tropical Northern Australia

    International Nuclear Information System (INIS)

    Twining, J.; Payne, T.; Russell, R.; Wilde, K; McOrist, G.; Wong, H.; Shotton, P.; Tagami, K.; Itakura, T.

    2003-01-01

    Soil-to-plant radionuclide transfer factors for cesium ( 134 Cs), strontium ( 85 Sr) and zinc ( 65 Zn) into sorghum and mung plants grown in tropical Australia have been determined over a four-year study period. The crops were grown on two types of red earth soils. Transfer factors for Cs and Sr are not substantially different from the expected values based on previous studies, reported in the general literature and compiled in the IUR database, mainly performed within temperate climates. In contrast, the values for zinc (Zn) are more than an order of magnitude greater than anticipated. Most of the radioactivity added to the soils has been retained in the top 5 cm of both soils. There has been a general decline in soil-to-plant transfer of Cs and Zn as time has increased

  5. Human metabolism and ecological transfer of radioactive caesium. Comparative studies of Chernobyl debris and nuclear weapons fallout, in southern Sweden and in Bryansk, Russia

    International Nuclear Information System (INIS)

    Raeaef, C.L.

    2000-05-01

    The whole-body content of radiocaesium was measured in a South Swedish urban group of people residing in the city of Lund between 1960 and 1994. The results from the survey have been analysed in order to estimate the ecological half time, T eff,eco of fallout radiocaesium, and the aggregate transfer from ground deposition to man in the region. After 1987, the biological half times, T e of 137 Cs and 40 K in man were also determined in the reference group through whole-body content measurements in combination with 24-hour urine sampling. Relationships between 24-hour urinary excretion and body burden of 137 Cs in the group together with data from the literature were then applied to urine samples collected in 1994 and 1995 from adult subjects living in the highly contaminated region of Bryansk, Russia, in order to estimate their average body burden of 137 Cs. The equivalent biological half-time for 137 Cs in females of the Lund reference group was, on average 66±3 d, which agrees with other findings, whereas the value for the males, 81±4 d, was, on average, significantly lower than what is found in the literature. This is partly explained by the elevated mean age and relatively low mean body muscle mass of the males investigated. The 137 Cs from nuclear weapons tests in the 1950s and 1960s still gave a significant contribution to the total 137 Cs levels in man during the post-Chernobyl study period (1987-1994). About 10% of the peak post-Chernobyl concentration level of 137 Cs (3.5-4 Bq/kg) in 1987, was attributed to pre-Chernobyl 137 Cs. The effective ecological half-time for 137 Cs from Chernobyl was found to be 1.8±0.2 y. The time-integrated aggregate transfer of 137 Cs from ground deposition to mean activity concentration in man was estimated to be 0.4 Bq/kg/kBq/m 2 . These values may be compared with an effective ecological half-time of 1.3 years found in the Lund reference group in the 1960s, and in time-integrated aggregate transfer factor of 4.4 Bq/kg/kBq/m 2 . The average committed effective dose from ingested 137 Cs Chernobyl fallout in the study group was estimated to be 0.02 mSv and from the nuclear weapons fallout to 0.20 mSv. The estimates of whole-body content of 137 Cs in the Russian subjects obtained through creatinine normalisation of the 137 Cs content in urine were, on average, a factor of 2 higher than estimates obtained through a potassium normalisation procedure; 55±8 kBq for creatinine and 29±4 kBq for potassium normalisation in the year 1994. This was due to a significant difference in the relationship between the urinary potassium and creatinine concentration between the Swedish and Russian group. The elevated potassium concentration found in the rural Russian subjects indicated a higher dietary intake of potassium, which greatly influence the accuracy and applicability of the potassium normalization method when estimating body burden of 137 Cs through urine assay. It is therefore recommended not to use the potassium normalisation procedure in cases where the daily intake of potassium is unknown. The estimated body burden of 137 Cs in the Bryansk group in 1994 corresponds to a contribution to the estimated annual effective dose of 1.8 mSv/y, which is approximately 200 times greater than the average annual dose received from ingested 137 Cs by the subjects of the Lund reference group during the period 1987-1994

  6. Irradiation of members of the general public from radioactive caesium following the Chernobyl reactor accident. Field studies in a highly contaminated area in the Bryansk region, Russia

    Energy Technology Data Exchange (ETDEWEB)

    Thornberg, C

    2000-11-01

    From 1990 to 1999, estimations of the effective dose from external as well as internal irradiation from {sup 137}Cs and {sup 134}Cs were carried out for inhabitants in rural villages in the Bryansk region, Russia, highly contaminated due to the Chernobyl accident in 1986. The villages were situated about 180 km from the Chernobyl power plant and the deposition of {sup 137}Cs was in the range 0.9-2.7 MBq/m{sup 2}. Yearly expeditions were conducted in autumn by members of the Departments of Radiation Physics in Malmoe and Goeteborg, Institute of Radiation Hygiene, St. Petersburg and the the first 5 years also by the Norwegian Radiation Protection Authority. The dose levels and their change in time were estimated for various groups of the general public. The body burden of {sup 134,137}Cs and hence, the effective dose, was estimated from measurements of the urinary concentration of cesium radionuclides, together with direct measurements of the body content using a portable detector. The effective dose from external irradiation was estimated from measurements with thermoluminescent dosemeters worn by the participants during one month each year. In a special case study, the changes in biokinetics of {sup 137}Cs during pregnancy was investigated in a woman with an unintended intake of {sup 137}Cs via mushrooms from a highly contaminated forest in the area. During pregnancy there is an increased excretion of cesium resulting in a biological half-time of cesium which was 54% of the half-time before pregnancy. The ratio of the {sup 137}Cs concentration in breast milk (Bq/l) to that in the mother's body (Bq/kg) was 15% one month after the child was born. The body burden of {sup 137}Cs in the Russian individuals calculated from the concentration of {sup 137}Cs in urine showed a good agreement with the body burden estimated from in vivo measurements in the same individuals. Normalisation of the cesium concentration in the urine samples by the use of potassium or creatinine excretion was found to introduce systematic differences as well as larger spread in the calculated values of the {sup 137}Cs body burden as compared with calculations without normalisation, using the urinary concentration of {sup 137}Cs only. The yearly effective dose from external and internal irradiation to inhabitants in the Russian villages varied between 1.2 and 2.5 mSv as a mean for all villages studied between 1991 and 1998 and the internal effective dose was, on average, 30-50% of the total effective dose during that period. The effective dose from external irradiation decreased on average 15% per year, while the effective dose from internal irradiation varied, depending to a great extent on dietary habits and especially the availability of mushrooms. The cumulated effective dose for a 70-year period after the accident was calculated to be around 100 mSv with the assumption that the effective dose will decrease by only the physical decay of {sup 137}Cs (2% per year) after 1999. Individuals may receive considerably higher effective doses, up to 0.5 Sv during a life-time considering the large spread in dose values among individuals.

  7. Experimental contamination of margaritana margaritifera (L) (a Fresh water bivalve) by caesium 137; Contamination experimentale de margaritana margaritifera (L) (bivalve d'eau douce) par le cesium 137

    Energy Technology Data Exchange (ETDEWEB)

    Foulquier, L; Bovard, P; Grauby, A [Commissariat a l' Energie Atomique, Cadarache (France). Centre d' Etudes Nucleaires

    1966-07-01

    The hydro biological research carried out in the Radio-Ecology Section has led the authors to study some Margaritana sampling stations situated down-stream from the Monts d'Arree nuclear power station. They describe the preservation and contamination methods used for fixing the {sup 137}Cs concentration factors in the case of Margaritana Margaritifera (L). The results of experiments carried out over a period of one hundred days show that the specific activity of the various organs is stabilized after thirty to thirty-five days. The authors have noticed a relatively low adsorption on the shell through the intermediary of micro-organisms, and a strong and rapid absorption in the soft parts. The concentration factors have values, at equilibrium, of around: 9 for the shell, 300 for all the organs, and 38 for the whole animal. A comparison of these results with work published by other authors makes it possible to draw general conclusions concerning the mechanism of {sup 137}Cs fixation by lamellibranch, as well as their capacity of fixation. (author) [French] Les etudes hydrobiologiques effectuees au sein de la Section de Radio-Ecologie ont amene les auteurs a etudier des stations de prelevement de Margaritana en aval de la Centrale Nucleaire des Monts d'Arree. Ils decrivent les methodes de conservation et de contamination utilisees pour l'etablissement des facteurs de concentration du {sup 137}Cs par Margaritana margaritifera (L). Les resultats des experimentations menees pendant cent jours montrent que les activites specifiques de la coquille et des differents organes se stabilisent au bout de trente a trente-cinq jours. Les auteurs constatent une adsorption relativement faible sur la coquille par l'intermediaire des micro-organismes et une absorption forte et rapide dans les parties molles. Les facteurs de concentration se situent, a l'equilibre, autour de: 9 pour la coquille, 300 pour l'ensemble des organes et 38 si l'on considere l'animal total. Cette etude comparee a celles deja effectuees par d'autres auteurs permet de degager des idees generales sur le mode et la capacite de fixation du {sup 137}Cs par les lamellibranches. (auteur)

  8. Irradiation of members of the general public from radioactive caesium following the Chernobyl reactor accident. Field studies in a highly contaminated area in the Bryansk region, Russia

    International Nuclear Information System (INIS)

    Thornberg, C.

    2000-11-01

    From 1990 to 1999, estimations of the effective dose from external as well as internal irradiation from 137 Cs and 134 Cs were carried out for inhabitants in rural villages in the Bryansk region, Russia, highly contaminated due to the Chernobyl accident in 1986. The villages were situated about 180 km from the Chernobyl power plant and the deposition of 137 Cs was in the range 0.9-2.7 MBq/m 2 . Yearly expeditions were conducted in autumn by members of the Departments of Radiation Physics in Malmoe and Goeteborg, Institute of Radiation Hygiene, St. Petersburg and the the first 5 years also by the Norwegian Radiation Protection Authority. The dose levels and their change in time were estimated for various groups of the general public. The body burden of 134,137 Cs and hence, the effective dose, was estimated from measurements of the urinary concentration of cesium radionuclides, together with direct measurements of the body content using a portable detector. The effective dose from external irradiation was estimated from measurements with thermoluminescent dosemeters worn by the participants during one month each year. In a special case study, the changes in biokinetics of 137 Cs during pregnancy was investigated in a woman with an unintended intake of 137 Cs via mushrooms from a highly contaminated forest in the area. During pregnancy there is an increased excretion of cesium resulting in a biological half-time of cesium which was 54% of the half-time before pregnancy. The ratio of the 137 Cs concentration in breast milk (Bq/l) to that in the mother's body (Bq/kg) was 15% one month after the child was born. The body burden of 137 Cs in the Russian individuals calculated from the concentration of 137 Cs in urine showed a good agreement with the body burden estimated from in vivo measurements in the same individuals. Normalisation of the cesium concentration in the urine samples by the use of potassium or creatinine excretion was found to introduce systematic differences as well as larger spread in the calculated values of the 137 Cs body burden as compared with calculations without normalisation, using the urinary concentration of 137 Cs only. The yearly effective dose from external and internal irradiation to inhabitants in the Russian villages varied between 1.2 and 2.5 mSv as a mean for all villages studied between 1991 and 1998 and the internal effective dose was, on average, 30-50% of the total effective dose during that period. The effective dose from external irradiation decreased on average 15% per year, while the effective dose from internal irradiation varied, depending to a great extent on dietary habits and especially the availability of mushrooms. The cumulated effective dose for a 70-year period after the accident was calculated to be around 100 mSv with the assumption that the effective dose will decrease by only the physical decay of 137 Cs (2% per year) after 1999. Individuals may receive considerably higher effective doses, up to 0.5 Sv during a life-time considering the large spread in dose values among individuals

  9. Human metabolism and ecological transfer of radioactive caesium. Comparative studies of Chernobyl debris and nuclear weapons fallout, in southern Sweden and in Bryansk, Russia

    Energy Technology Data Exchange (ETDEWEB)

    Raeaef, C.L

    2000-05-01

    The whole-body content of radiocaesium was measured in a South Swedish urban group of people residing in the city of Lund between 1960 and 1994. The results from the survey have been analysed in order to estimate the ecological half time, T{sub eff,eco} of fallout radiocaesium, and the aggregate transfer from ground deposition to man in the region. After 1987, the biological half times, T{sub e} of {sup 137}Cs and {sup 40}K in man were also determined in the reference group through whole-body content measurements in combination with 24-hour urine sampling. Relationships between 24-hour urinary excretion and body burden of {sup 137}Cs in the group together with data from the literature were then applied to urine samples collected in 1994 and 1995 from adult subjects living in the highly contaminated region of Bryansk, Russia, in order to estimate their average body burden of {sup 137}Cs. The equivalent biological half-time for {sup 137}Cs in females of the Lund reference group was, on average 66{+-}3 d, which agrees with other findings, whereas the value for the males, 81{+-}4 d, was, on average, significantly lower than what is found in the literature. This is partly explained by the elevated mean age and relatively low mean body muscle mass of the males investigated. The {sup 137}Cs from nuclear weapons tests in the 1950s and 1960s still gave a significant contribution to the total {sup 137}Cs levels in man during the post-Chernobyl study period (1987-1994). About 10% of the peak post-Chernobyl concentration level of {sup 137}Cs (3.5-4 Bq/kg) in 1987, was attributed to pre-Chernobyl {sup 137}Cs. The effective ecological half-time for {sup 137}Cs from Chernobyl was found to be 1.8{+-}0.2 y. The time-integrated aggregate transfer of {sup 137}Cs from ground deposition to mean activity concentration in man was estimated to be 0.4 Bq/kg/kBq/m{sup 2}. These values may be compared with an effective ecological half-time of 1.3 years found in the Lund reference group in the 1960s, and in time-integrated aggregate transfer factor of 4.4 Bq/kg/kBq/m{sup 2}. The average committed effective dose from ingested {sup 137}Cs Chernobyl fallout in the study group was estimated to be 0.02 mSv and from the nuclear weapons fallout to 0.20 mSv. The estimates of whole-body content of {sup 137}Cs in the Russian subjects obtained through creatinine normalisation of the {sup 137}Cs content in urine were, on average, a factor of 2 higher than estimates obtained through a potassium normalisation procedure; 55{+-}8 kBq for creatinine and 29{+-}4 kBq for potassium normalisation in the year 1994. This was due to a significant difference in the relationship between the urinary potassium and creatinine concentration between the Swedish and Russian group. The elevated potassium concentration found in the rural Russian subjects indicated a higher dietary intake of potassium, which greatly influence the accuracy and applicability of the potassium normalization method when estimating body burden of {sup 137}Cs through urine assay. It is therefore recommended not to use the potassium normalisation procedure in cases where the daily intake of potassium is unknown. The estimated body burden of {sup 137}Cs in the Bryansk group in 1994 corresponds to a contribution to the estimated annual effective dose of 1.8 mSv/y, which is approximately 200 times greater than the average annual dose received from ingested {sup 137}Cs by the subjects of the Lund reference group during the period 1987-1994.

  10. Radioactive fallout in the South Pacific : a history. Part 3: strontium-90 and caesium-137 deposition in New Zealand and resulting contamination of milk

    International Nuclear Information System (INIS)

    Matthews, K.M.

    1993-12-01

    The report provides a comprehensive analysis of milk radioactivity data, principally pertaining to 90 Sr and 137 Cs, collected in nine regions of New Zealand. Fallout deposition data are also reviewed and relationships between deposition and resulting milk contamination described. This report provides further information on 90 Sr deposition in New Zealand and summarises period from 1961 to 1990. Trends in levels of 90 Sr and 137 Cs in milk over long periods and also annual trends are described, together with variations between regions, modelled relationships between fallout deposition and milk contamination levels, measurements of 131 I and 89 Sr in milk, and estimates of resulting dietary radiation exposure in New Zealand. A major aim of the present report was to summarise as much of the information contained in the deposition and dairy product databases as possible through the description of trends and derivation of relationships in order to improve understanding of the behaviour of artificial radioactive contaminants in the environment and their passage through food-chains. 34 refs., 29 tabs., 50 figs., 1 ill

  11. Radioactivity distribution of the fruit trees ascribable to radioactive fall out (5). Transfer of caesium-137 from scion to other organs in 'Kyoho' grapes

    International Nuclear Information System (INIS)

    Takata, Daisuke; Yasunaga, Eriko; Sato, Mamoru; Abe, Kazuhiro; Tanoi, Keitaro

    2013-01-01

    We examined the effect on shifts of "1"3"7Cs from old organs to newly other organ with grafting scion contaminated by radionuclides onto non-radioactive contamination tree in grapes. "1"3"7Cs of about 20% in the scion had transferred to newly organs. In the scion, the concentration of "1"3"7Cs in bark after harvest was similar to that measured before grafting, but the concentration of "1"3"7Cs in wood after harvest was lower than that measured before grafting. We concluded that transferability of "1"3"7Cs from old branches to fruits had contributed much more than that from soil known in previous research. (author)

  12. Use of some inorganic and organic compounds as decontaminants for cobalt-60 and caesium-134 by clover plant grown on Inshas sandy soil

    Energy Technology Data Exchange (ETDEWEB)

    Abdel Sabour, M.F.; El-Naggar, H.A.; Soliman, S.M. (Atomic Energy Establishment, Cairo (Egypt). Nuclear Chemistry Dept.)

    1991-01-01

    Outdoor lysimeter experiments were carried out to elucidate the effect of 4 inorganic and 3 organic salts on {sup 60}Co and {sup 134}Cs uptake and dry matter yield of three cuts of clover in the soils of Inshas. A new concept was proposed for assessing the difference in capacity of soil to supply radionuclides to plants as affected by applied inorganic or organic compounds. A relation of plant tissue radionuclide content with time can be expressed in an exponential equation with corresponding regression coefficients. When the same plant species is grown on the same soil differing only in the applied compounds (e.g. Fe-EDDHA, Fe-DTPA, Fe-OAC, Fe(COO){sub 2}, Al(OH){sub 3}, Ca(H{sub 2}PO{sub 4}){sub 2}, Fe{sub 2}O{sub 3}) the derived equation will change. Differences of either Co or Cs accumulation with time between control and any other treatment were evaluated. The data also show that Fe-DTPA is preferred for {sup 60}Co as enhancing compound for plant uptake (for decontamination use), compared with other applied salts, on the other hand, any tested salts did not significantly effect {sup 134}Cs taken by clover. It was also found that more than 70% of the total cobalt uptake was accumulated in the roots which indicate that Co is less mobile in plants than Cs. (orig.).

  13. Use of some inorganic and organic compounds as decontaminants for cobalt-60 and caesium-134 by clover plant grown on Inshas sandy soil

    International Nuclear Information System (INIS)

    Abdel Sabour, M.F.; El-Naggar, H.A.; Soliman, S.M.

    1991-01-01

    Outdoor lysimeter experiments were carried out to elucidate the effect of 4 inorganic and 3 organic salts on 60 Co and 134 Cs uptake and dry matter yield of three cuts of clover in the soils of Inshas. A new concept was proposed for assessing the difference in capacity of soil to supply radionuclides to plants as affected by applied inorganic or organic compounds. A relation of plant tissue radionuclide content with time can be expressed in an exponential equation with corresponding regression coefficients. When the same plant species is grown on the same soil differing only in the applied compounds (e.g. Fe-EDDHA, Fe-DTPA, Fe-OAC, Fe(COO) 2 , Al(OH) 3 , Ca(H 2 PO 4 ) 2 , Fe 2 O 3 ) the derived equation will change. Differences of either Co or Cs accumulation with time between control and any other treatment were evaluated. The data also show that Fe-DTPA is preferred for 60 Co as enhancing compound for plant uptake (for decontamination use), compared with other applied salts, on the other hand, any tested salts did not significantly effect 134 Cs taken by clover. It was also found that more than 70% of the total cobalt uptake was accumulated in the roots which indicate that Co is less mobile in plants than Cs. (orig.) [de

  14. Transfer across the human gut of environmental plutonium, americium, cobalt, caesium and technetium: studies with cockles (Cerastoderma edule) from the Irish Sea

    International Nuclear Information System (INIS)

    Hunt, G.J.

    1998-01-01

    Our previous studies have indicated lower values of the gut transfer factor ('f L values') for plutonium and americium in winkles (Littorina littorea) than adopted by ICRP. The present study was undertaken primarily to investigate whether this observation extends to other species. Samples of cockles (Cerastoderma edule) from Ravenglass, Cumbria were eaten by volunteers who provided 24 samples of urine and faeces. Urine samples indicated f L values for cockles which were higher than for winkles; for plutonium these ranged overall up to 7x10 -4 with an arithmetic mean in the range (2-3)x10 -4 , and for americium up to 2.6x10 -4 with an arithmetic mean of 1.2x10 -4 . Limited data based on volunteers eating cockles from the Solway suggest that f L values for americium may be greater at distance from Sellafield. The measured values compare with 5x10 -4 used by the ICRP for environmental forms of both elements, which would appear to provide adequate protection when calculating doses from Cumbrian cockles. Data for other nuclides were obtained by analysing faecal samples from the volunteers who ate the Ravenglass cockles. Cobalt-60 showed an f L value in the region of 0.2, twice the value currently used by ICRP. For 137 Cs, variabilities were indicated in the range 0.08 to 0.43, within the ICRP value of f L =1.0. Technetium-99 gave f L values up to about 0.6, in reasonable conformity with the ICRP value of 0.5. (author)

  15. Transfer of some artificial (strontium 85 and caesium 137) and natural (potasium 40 and radium 226) radionuclides from milk to its products

    International Nuclear Information System (INIS)

    Al-Masri, M. S.; Nashawati, A.; Amin, Y.; Al-Akel, B.

    2004-12-01

    Transfer of some artificial radionuclides ( 137 Cs and 85 Sr) and natural radionuclides ( 226 Ra and 40 K) from milk (cheep and cows) to its products processed according to local manufacturing procedures (home made cheese, kashkawan cheese, shelal cheese, haloom cheese, kareshah cheese, sharkasiah cheese, liquid cheese, yogurt, butter and keshdah) has been studied. The results showed that the retention percent of radium 226 in milk products has reached %100 in the home made cheese and %72 for strontium 85 in the shelal cheese and %40 for cesium 137 in yogurt and %46 for potassium 40 also in yogurt. In addition, most of the retention percent ratios of the studied radionuclides in yogurt were relatively low (about %25 and % 40 in the yogurt processed from the milk of the cows and cheep respectively) with a high processing efficiency, so that making yogurt from the contaminated milk is the best way to reduce the contamination ratio and to make use of the contaminated milk. Furthermore, home made cheese was processed with salty solutions of different concentrations and the results showed that about %90 of cesium and potassium has transferred to the salty solution of %5 soaked for 48 hours, while %40 of the radium and %80 of strontium were removed from the contaminated cheese after 48 hours soaking in a salty solution of %2.5. However, the results of the present work can be used for processing of contaminated milk with artificial radionuclides in order to be utilized. (Authors)

  16. Summation of the high orders of perturbation theory for the parity nonconcerving E1-amplitude of 6s-7s-transition in Caesium atom

    International Nuclear Information System (INIS)

    Dzyuba, V.A.; Flambaum, V.V.; Sushkov, O.P.

    1989-01-01

    Three dominating subsequences of diagrams in the correlation correction to amplitude are summed: screening of the electron-electron interaction, particle-hole interaction and the iterations of the self-energy. The result of calculations is: E1(6s-7s)=(0.91±0.01)x10 -11 iea B (-Q W /N), Q W is the weak charge of nucleus, N is the number of neutrons. The calculations give the following value of the Weinberg angle: sin 2 Θ W =0.226±0.007(exp.)±0.004(theor.). 30 refs.; 7 figs.; 3 tabs

  17. Caesium-137 in sandy sediments of the River Loire (FR): Assessment of an alluvial island evolving over the last 50 years

    Energy Technology Data Exchange (ETDEWEB)

    Detriche, Sebastien; Rodrigues, Stephane; Macaire, Jean-Jacques; Breheret, Jean-Gabriel; Bakyono, Jean-Paul [Universite Francois-Rabelais de Tours, CNRS/INSU UMR 6113 ISTO, Universite d' Orleans Faculte des Sciences et Techniques, Laboratoire de Geologie des Environnements Aquatiques Continentaux, Parc de Grandmont, 37200 Tours (France); Bonte, Philippe [UMR CNRS-CEA 1572, Laboratoire des Sciences du Climat et de l' Environnement - LSCE, CNRS, Domaine du CNRS, Bat. 12, 91198 Gif-sur-Yvette (France); Juge, Philippe [CETU-Elmis ingenieries, Antenne Universitaire en Val de Vienne, 11 quai Danton, 37500 Chinon (France)

    2010-07-01

    Recent sedimentological and morphological evolution of an island in the River Loire (FR) was investigated using the {sup 137}Cs method. This study describes the morphological adjustment of the island in the last 50 years, which corresponds to the increased bed incision of this sandy, multiple-channel environment because of, among other things, the increase in sediment extraction up to 1995. The results show that some {sup 137}Cs can be retained by sandy particles, potentially in clay minerals forming weathering features included in detrital sand grains. From a morphological perspective, significant lateral erosion can be observed in the upstream part of the island, while a weak lateral accretion occurs in its downstream section. Data about {sup 137}Cs and aerial photographs show that the morphology of the island margins has undergone significant changes leading to a lateral migration, while the centre of the island has remained relatively stable or is slowly eroding. The migration of the island depends on: (1) the withdrawal of inherited pre-incision morphological units, such as levees, or the development of new units, such as a channel shelf; (2) water and sediment supply from surrounding channels during flood events; (3) preferential sediment trapping (20 mm year{sup -1}) from the presence of riparian vegetation on the bank of the secondary channel that is subject to narrowing. The sedimentological and morphological response of the island in the context of incision of the Loire river bed is expressed mainly by lateral migration and secondarily by a low vertical adjustment. (authors)

  18. Radioactive caesium (134Cs and 137Cs) in mushrooms of the genus Boletus from the Reggio Emilia in Italy and Pomerania in Poland.

    Science.gov (United States)

    Cocchi, Luigi; Kluza, Karolina; Zalewska, Tamara; Apanel, Anna; Falandysz, Jerzy

    2017-12-01

    Activity concentrations of 134 Cs and 137 Cs were determined in mushrooms of the Boletus species B. aereus, B. reticulatus, B. appendiculatus, B. calopus, B. edulis, B. erythropus, B. fechtneri, B. pinophilus, B. pseudoregius, B. rhodopurpureus, B. rhodoxanthus collected in the Reggio Emilia, Italy, in 1993 and 1994 and in B. edulis collected in Pomerania in northern Poland in the period from 1995-2015. Boletus edulis from the Reggio Emilia showed presence of 137 Cs at 330 ± 220 Bq kg -1 dry biomass in 1993 and at 370 ± 180 Bq kg -1 dry biomass in 1994. In B. edulis sampled in the Reggio Emilia in 1993 and 1994, the pre-Chernobyl 137 Cs from global fallout amounted to 39-46 % of the total activity concentrations of isotope 137 Cs. B. edulis from Pomerania contained 137 Cs in caps at 270 ± 15 Bq kg -1 dry biomass in 1995, and in whole fruiting bodies it was found to be 470 ± 9 Bq kg -1 dry biomass in 2015. The activity concentrations of 137 Cs determined in fruiting bodies of B. edulis from Pomerania fluctuated but persisted over the period from 1995 to 2015, while the maximum activity concentrations were well below the tolerance limit of 600 Bq kg -1 fresh product.

  19. 137Caesium in samples of wild-grown Boletus edulis Bull. from Lucca province (Tuscany, Italy) and other Italian and European geographical areas.

    Science.gov (United States)

    Betti, Laura; Palego, Lionella; Lucacchini, Antonio; Giannaccini, Gino

    2017-01-01

    Samples of the edible mushroom Boletus edulis Bull. were studied to assess the risk for human health related to their content of the artificial radionuclide 137 Cs. Fresh B. edulis carpophores were collected in four undeveloped microhabitats of Lucca province (Tuscany, North-Central Italy). Dried non-cultivated samples coming from this same district and 11 other Italian provinces or European countries were instead purchased fromcommercial sources. Contents of 137 Cs, reported as Bq kg ‒1 dry weight (dw), were measured by γ-spectrometry. The radionuclide concentration varied depending on the gathering site in fresh samples, with 41.8 ± 5.2 Bq kg ‒1 dw at site 1 (Tosco-Emiliani Apennine) and four-fold less, 12.8 ± 1.3 Bq kg ‒1 dw, at site 2 (Apuan Alps). Moreover, fresh or dried carpophores from Lucca province displayed among the lowest 137 Cs contents in Europe. Average 137 Cs levels in all analysed samples were substantially below the legal threshold for edible mushrooms, 600 Bq kg ‒1 dw. Conclusively, we report that 137 Cs amounts in B. edulis depend on both the distance from the Chernobyl accident and multifactorial features of collection sites. We also show that the consumption of European B. edulis does not represent a major health risk with respect to 137 Cs radio contamination.

  20. Current radiological situation in areas of Ukraine contaminated by the Chernobyl accident: Part 1. Human dietary exposure to Caesium-137 and possible mitigation measures.

    Science.gov (United States)

    Labunska, I; Kashparov, V; Levchuk, S; Santillo, D; Johnston, P; Polishchuk, S; Lazarev, N; Khomutinin, Y

    2018-08-01

    This study reports for the first time temporal trends for the period of 2011-2016 in 137 Cs content in cow's milk originating from private farms and households of 14 settlements located in the territories of the Rivne region, Ukraine. These areas are still radioactively contaminated as a result of the accident at the Chernobyl Nuclear Power Plant (ChNPP) in 1986. In 2016, the average 137 Cs activity concentration in milk exceeded the Ukrainian Permissible Level (PL) for adults of 100 Bq/l in samples from 6 settlements and the PL for children of 40 Bq/l in 8 settlements, reaching activity concentration of around 500 Bq/l in some samples. Estimated annual effective doses calculated utilizing two different methodologies were in the range of 1.4-2.6 mSv/year and 1.2-1.8 mSv/year, respectively. The estimated effective period of milk semi-purification (T 1/2 _ eff ) from 137 Cs in these settlements was in the range from 8 to 17 years. The estimated ecological period of milk semi-purification (T 1/2 _ eco ) from 137 Cs was in the range from 11 to 36 years. The optimization of the remedial actions strategy for investigated settlements exposed to an effective dose above 1 mSv/year (as estimated in 2016) has shown that a diversity of measures can decrease effective dose for a representative person to below 1 mSv/year. Such measures include application of Ferrocyn to cows, mineral fertilization of potato fields, information campaigns on consumption of wild mushrooms and other forestry products, and feeding pigs with uncontaminated fodder. The total costs of such measures are estimated to be about 71,000 Euro per year for the combined population (8336 inhabitants) of the six villages investigated in this study that showed the highest median residual 137 Cs activity concentrations in milk, with a subsequent decrease in cost in the future. This would result in an averted collective dose of 11 man-Sv, at an average cost of 6.5 kEuro/man-Sv averted. In the absence of governmental programs for implementation of necessary protective measures to reduce radiological risks to impacted populations, the exceedance of PL for the activity concentration of 137 Cs in cow's milk for adults of 100 Bq/l in the Chernobyl-affected areas of Ukraine could persist for many more years - until at least 2040. Copyright © 2018 Elsevier Ltd. All rights reserved.

  1. Caesium-137 soil-to-plant transfer for representative agricultural crops of monocotyledonous and dicotyledonous plants in post-Chernobyl steppe landscape

    Science.gov (United States)

    Paramonova, Tatiana; Komissarova, Olga; Turykin, Leonid; Kuzmenkova, Natalia; Belyaev, Vladimir

    2016-04-01

    The accident at the Chernobyl nuclear power plant in 1986 had a large-scale action on more than 2.3 million hectares agricultural lands in Russia. The area of radioactively contaminated chernozems of semi-arid steppe zone with initial levels of Cs-137 185-555 kBq/m2 in Tula region received the name "Plavsky radioactive hotspot". Nowadays, after the first half-life period of Cs-137 arable chernozems of the region are still polluted with 3-6-fold excess above the radioactive safety standard (126-228 kBq/m2). Therefore, qualitative and quantitative characteristics of Cs-137 soil-to-plant transfer are currently a central problem for land use on the territory. The purpose of the present study was revealing the biological features of Cs-137 root uptake from contaminated arable chernozems by different agricultural crops. The components of a grass mixture growing at the central part of Plavsky radioactive hotspot with typical dicotyledonous and monocotyledonous plants - galega (Galega orientalis, Fabaceae family) and bromegrass (Bromus inermis, Gramineae family) respectively - were selected for the investigation, that was conducted during the period of harvesting in 2015. An important point was that the other factors influenced on Cs-137 soil-to-plant transfer - the level of soil pollution, soil properties, climatic conditions, vegetative phase, etc. - were equal. So, biological features of Cs-137 root uptake could be estimated the most credible manner. As a whole, general discrimination of Cs-137 root uptake was clearly shown for both agricultural crops. Whereas Cs-137 activity in rhizosphere 30-cm layer of arable chernozem was 371±74 Bq/kg (140±32 kBq/m2), Cs-137 activities in plant biomass were one-two orders of magnitude less, and transfer factor (TF) values (the ratio of the Cs-137 activities in vegetation and in soil) not exceeded 0.11. At the same time bioavailability of Cs-137 for bromegrass was significantly higher than for galega: TFs in total biomass of the crops were 0.11 and 0.01 correspondingly. But the most dramatic difference between the investigated crops was connected with peculiarities of Cs-137 distribution within above- and belowground parts of biomass. While TF in aboveground fraction of galega (0.02) was slightly higher than in belowground fraction (0.01), the bulk of Cs-137 in bromegrass was detected not in shoots but in roots (TFs 0.05 and 0.11 correspondingly). More extensive examination of Cs-137 behavior in "soil-plant" systems of agricultural crops in the area of Plavsky radioactive hotspot has revealed that all investigated dicotyledonous plants with taproot system (potatoes, soya, amaranth, rape) accumulated 71±14% of Cs-137 inventories in aboveground biomass, whereas monocotyledonous plants with fibrous root system (wheat, barley, maize, cereal pasture species) deposited 94±5% of Cs-137 supplies in their belowground biomass. Thus, the first had effective biological root barrier protecting vegetation from general Cs-137 incorporation into biomass, but relatively active radionuclide translocation into shoots, while the second were characterized by slight rhizofiltration property and occurrence an additional barrier between roots and shoots determining only moderate radionuclide translocation into aboveground biomass. Such biological features should be taken into account in deciding on rehabilitation strategy of radioactively contaminated lands. The study was conducted with the support from the Russian Foundation for Basic Research (project no. 14-05-00903).

  2. Sympathetic cooling in a rubidium cesium mixture: Production of ultracold cesium atoms; Sympathetisches Kuehlen in einer Rubidium-Caesium-Mischung: Erzeugung ultrakalter Caesiumatome

    Energy Technology Data Exchange (ETDEWEB)

    Haas, M.

    2007-07-01

    This thesis presents experiments for the production of ultracold rubidium cesium mixture in a magnetic trap. The long-termed aim of the experiment is the study of the interaction of few cesium atoms with a Bose-Einstein condensate of rubidium atoms. Especially by controlled variation of the cesium atom number the transition in the description of the interaction by concepts of the one-particle physics to the description by concepts of the many-particle physics shall be studied. The rubidium atoms are trapped in a magneto-optical trap (MOT) and from there reloaded into a magnetic trap. In this the rubidium atoms are stored in the state vertical stroke f=2,m{sub f}=2 right angle of the electronic ground state and evaporatively cooled by means of microwave-induced transitions into the state vertical stroke f=1,m{sub f}=1] (microwave cooling). The cesium atoms are also trppaed in a MOT and into the same magnetic trap reloaded, in which they are stored in the state vertical stroke f=4,m{sub f}=4 right angle of the electronic ground state together with rubidium. Because of the different hyperfine splitting only rubidium is evaporatively cooled, while cesium is cooled jointly sympathetically - i.e. by theramal contact via elastic collisions with rubidium atoms. The first two chapters contain a description of interatomic interactions in ultracold gases as well as a short summary of theoretical concepts in the description of Bose-Einstein condensates. The chapters 3 and 4 contain a short presentation of the methods applied in the experiment for the production of ultracold gases as well as the experimental arrangement; especially in the framework of this thesis a new coil system has been designed, which offers in view of future experiments additionally optical access for an optical trap. Additionally the fourth chapter contains an extensive description of the experimental cycle, which is applied in order to store rubidium and cesium atoms together into the magnetic trap. The last chapter finally contains the experimental results as well as the analysis of which. In experiments, which involve only rubidium, rubidium is coolde by means of microwave cooling; thereby an unwanted population of the state vertical stroke f=2,m{sub f}=1 right angle is observed, which hinders the condensation. The population of the state vertical stroke f=2,m{sub f}=1 right angle is systematically studied. The continuous depopulation of the state vertical stroke 2,1 right angle by means of a second microwave frequency radiated upon allows the production of rubidium condensates of 10{sup 5} atoms after 23 s evaporative cooling. By selective microwave cooling of the rubidium atoms the rubidium cesium mixtures are cooled until 700 mK. By means of a simple model the sympathetic cooling of cesium is analyzed, which allows a first characterization of the rubidium-cesium interaction.

  3. Plant induced changes in concentrations of caesium, strontium and uranium in soil solution with reference to major ions and dissolved organic matter

    International Nuclear Information System (INIS)

    Takeda, Akira; Tsukada, Hirofumi; Takaku, Yuichi; Akata, Naofumi; Hisamatsu, Shun'ichi

    2008-01-01

    For a better understanding of the soil-to-plant transfer of radionuclides, their behavior in the soil solution should be elucidated, especially at the interface between plant roots and soil particles, where conditions differ greatly from the bulk soil because of plant activity. This study determined the concentration of stable Cs and Sr, and U in the soil solution, under plant growing conditions. The leafy vegetable komatsuna (Brassica rapa L.) was cultivated for 26 days in pots, where the rhizosphere soil was separated from the non-rhizosphere soil by a nylon net screen. The concentrations of Cs and Sr in the rhizosphere soil solution decreased with time, and were controlled by K + NH 4 + and Ca, respectively. On the other hand, the concentration of U in the rhizosphere soil solution increased with time, and was related to the changes of DOC; however, this relationship was different between the rhizosphere and non-rhizosphere soil

  4. Plant induced changes in concentrations of caesium, strontium and uranium in soil solution with reference to major ions and dissolved organic matter.

    Science.gov (United States)

    Takeda, Akira; Tsukada, Hirofumi; Takaku, Yuichi; Akata, Naofumi; Hisamatsu, Shun'ichi

    2008-06-01

    For a better understanding of the soil-to-plant transfer of radionuclides, their behavior in the soil solution should be elucidated, especially at the interface between plant roots and soil particles, where conditions differ greatly from the bulk soil because of plant activity. This study determined the concentration of stable Cs and Sr, and U in the soil solution, under plant growing conditions. The leafy vegetable komatsuna (Brassica rapa L.) was cultivated for 26 days in pots, where the rhizosphere soil was separated from the non-rhizosphere soil by a nylon net screen. The concentrations of Cs and Sr in the rhizosphere soil solution decreased with time, and were controlled by K+NH(4)(+) and Ca, respectively. On the other hand, the concentration of U in the rhizosphere soil solution increased with time, and was related to the changes of DOC; however, this relationship was different between the rhizosphere and non-rhizosphere soil.

  5. Studies of environmental radioactivity in Cumbria. Part 6. The chronology of discharges of caesium-137, plutonium and americium-241 from BNFL Sellafield, as recorded in lake sediments

    Energy Technology Data Exchange (ETDEWEB)

    Eakins, J D; Cambray, R S

    1985-04-01

    A study has been made of the radionuclide content of lake sediments from Cumbria in order to determine the history of discharges of /sup 137/Cs and actinides from the Sellafield works of British Nuclear Fuels plc (BNFL). Sediment cores have been taken from Ullswater and Grasmere, which are remote from Sellafield, in order to establish the behaviour of nuclear weapon fallout nuclides. Cores have also been taken from Barfield Tarn, which is 19 km SE of Sellafield but close to the sea, and from Ponsonby and Harnsey Moss Tarns, close to Sellafield. All sediments were analysed for /sup 137/Cs and sup(239+240)Pu. Additional measurements of /sup 238/Pu and /sup 241/Am were made on samples from the closer tarns. The sediment cores were dated by the /sup 210/Pb method and, where appropriate, by the /sup 137/Cs technique also. The amounts of /sup 137/Cs and sup(239+240)Pu in sediments from Barfield Tarn could be accounted for by fallout from nuclear weapons, although the levels of /sup 241/Am were marginally greater. However in Harnsey Moss Tarn the levels of actinides indicated that they were derived mainly from material originally discharged to sea from Sellafield. Sediment from Ponsonby Tarn contained material derived mainly from discharges to atmosphere.

  6. Caesium-137 in soils in relation to the nine unit landsurface model in a semi-arid environment in Western Australia

    International Nuclear Information System (INIS)

    Loughran, R.J.; Pilgrim, A.T.; Conacher, A.J.

    1987-01-01

    The comparison of 137Cs levels at hillslope sites with input sites used in this study presented data time-averaged for the period since the onset of fallout, 1954. It also took no account of temporary fluctuations in fallout and soil movement. Consequently, relationships sought between shorter-term measurements of sediment yield and 137Cs loss may not be in total agreement. Furthermore, soil samples for 137Cs in each washtray catchment represented only a small fraction of the landsurface. Despite these apparent shortcomings, the 137Cs technique was able to discriminate between the more stable (unit 1) interfluve landsurfaces and units 5 (transportational midslope) and 6 (colluvial footslope) on Catena One, and to a lesser degree on Catena Two. The unit 6 sites had less 137Cs than unit 1 (input) sites and some of the profiles were truncated. Indications were that, while there was no 137Cs evidence for net soil gain over the past 30 years, the degree of soil loss was generally lower than on unit 5 sites on the same catena. Since the model does not define most landsurface unit in terms of dominance of a particular process but rather in terms of what pedogeomorphic processes and their diagnostic properties distinguish any given unit from other units' (Conacher and Dalrymple, 1977: 65), it may be concluded that 137Cs levels are another of these properties

  7. Spectral range calculation inside the Research Irradiating Facility Army Technology Center using code MCNPX and comparison with the spectra of energy Caesium 137 raised in laboratory

    International Nuclear Information System (INIS)

    Gomes, Renato G.; Rebello, Wilson F.; Cavaliere, Marcos Paulo; Vellozo, Sergio O.; Moreira Junior, Luis; Vital, Helio C.; Silva, Ademir X.

    2013-01-01

    Using the MCNPX code, the objective was to calculate by means of computer simulation spectroscopy range inside the irradiation chamber upper radiator gamma research irradiating facility Army Technology Center (CTEx). The calculations were performed in the spectral range usual 2 points for research purposes irradiating the energy spectra of gamma rays from the source of Cesium chloride 137. Sought the discretization of the spectrum in 100 channels at points of upper bound of 1cm higher and lower dose rates previously known. It was also conducted in the laboratory lifting the spectrum of Cesium-137 source using NaI scintillator detector and multichannel analyzer. With the source spectrum Cesium-137 contained in the literature and raised in the laboratory, both used as reference for comparison and analysis in terms of probability of emission maximum of 0.661 MeV The spectra were quite consistent in terms of the behavior of the energy distributions with scores. The position of maximum dose rate showed absorption detection almost maximum energy of 0.661 MeV photopeak In the spectrum of the position of minimum dosage rate, it was found that due to the removal of the source point of interest, some loss detection were caused by Compton scattering. (author)

  8. Human metabolism and ecological transfer of radioactive caesium: Comparative studies of Chernobyl debris and nuclear weapons fallout, in Southern Sweden and in Bryansk, Russia

    Science.gov (United States)

    Raaf, Christopher Leopold

    The whole-body content of radiocaesium was measured in a South-Swedish urban group of people residing in the city of Lund (55.7°N, 13.2°E) between 1960 and 1994. The results from the survey have been analysed in order to estimate the ecological half-time, Teff,eco, of fallout radiocaesium and the aggregate transfer from ground deposition to man in the region. After 1987, the biological half-times, Ts, of 137Cs and 40K in man were also determined in the reference group through whole-body content measurements in combination with 24-hour urine sampling. Relationships between 24-hour urinary excretion and body burden of 137Cs in the group together with data from the literature were then applied to urine samples collected in 1994 and 1995 from adult subjects living in the highly contaminated region of Bryansk, Russia, in order to estimate their average body burden of 137Cs. The equivalent biological half-time for 137Cs in females of the Lund reference group was, on average (+/-1 WSE), 66 +/- 3 d, which agrees with other findings, whereas the value for the males, 81 +/- 4 d, was, on average, significantly lower than what is found in the literature. This is partly explained by the elevated mean age and relatively low mean body muscle mass of the males investigated in the group during the post-Chernobyl study period. The effective ecological half-time for 137Cs from Chernobyl was found to be 1.8 +/- 0.2 y. The aggregate transfer of 137Cs from deposition to mean activity concentration in man was estimated to be 1.7 Bq kg-1/kBq m-2. These vales may be compared with an effective ecological half-time of 1.3 years found in the reference group in the 1960s, and an aggregate transfer factor of 9.8 Bq kg-1/kBq m-2. The average committed effective dose from ingested 137Cs Chernobyl fallout in the study group was estimated to be 0.02 mSv and from the nuclear weapons fallout to 0.20 mSv. The estimates of whole-body content of 137Cs in the Russian subjects obtained through creatinine normalisation of the 137Cs content in urine were, on average, a factor of 2 higher than estimates obtained through a potassium normalisation procedure; 55 +/- 8 (1 SE) kBq for creatinine and 29 +/- 4 (1 SE) kBq for potassium normalisation in the year 1994. This was due to a significant difference in the relationship between the urinary potassium and creatinine concentration between the Swedish and Russian group. The elevated potassium concentration found in the rural Russian subjects indicated a higher dietary intake of potassium, which greatly influences the accuracy and applicability of the potassium normalisation method when estimating body burden of 137Cs through urine assay. It is therefore recommended not to use the potassium normalisation procedure in cases where the daily intake of potassium is unknown. The estimated body burden of 137Cs in the Bryansk group in 1994 corresponds to a contribution to the estimated annual effective dose of 1.8 mSv y-1, which is approximately 200 times greater than the average annual dose received from ingested 137Cs by the subjects of the Lund reference group during the period 1987-1994.

  9. Caesium-137 in sandy sediments of the River Loire (FR): Assessment of an alluvial island evolving over the last 50 years

    International Nuclear Information System (INIS)

    Detriche, Sebastien; Rodrigues, Stephane; Macaire, Jean-Jacques; Breheret, Jean-Gabriel; Bakyono, Jean-Paul; Bonte, Philippe; Juge, Philippe

    2010-01-01

    Recent sedimentological and morphological evolution of an island in the River Loire (FR) was investigated using the 137 Cs method. This study describes the morphological adjustment of the island in the last 50 years, which corresponds to the increased bed incision of this sandy, multiple-channel environment because of, among other things, the increase in sediment extraction up to 1995. The results show that some 137 Cs can be retained by sandy particles, potentially in clay minerals forming weathering features included in detrital sand grains. From a morphological perspective, significant lateral erosion can be observed in the upstream part of the island, while a weak lateral accretion occurs in its downstream section. Data about 137 Cs and aerial photographs show that the morphology of the island margins has undergone significant changes leading to a lateral migration, while the centre of the island has remained relatively stable or is slowly eroding. The migration of the island depends on: (1) the withdrawal of inherited pre-incision morphological units, such as levees, or the development of new units, such as a channel shelf; (2) water and sediment supply from surrounding channels during flood events; (3) preferential sediment trapping (20 mm year -1 ) from the presence of riparian vegetation on the bank of the secondary channel that is subject to narrowing. The sedimentological and morphological response of the island in the context of incision of the Loire river bed is expressed mainly by lateral migration and secondarily by a low vertical adjustment. (authors)

  10. Salt-stimulation of caesium accumulation in the euryhaline green microalga Chlorella salina: potential relevance to the development of a biological Cs-removal process

    Energy Technology Data Exchange (ETDEWEB)

    Avery, S. V.; Codd, G. A.; Gadd, G. M. [Department of Biological Sciences, University of Dundee, Dundee DD1 4HN (United Kingdom)

    1993-07-01

    Accumulation of Cs{sup +} by Chlorella salina was 28-fold greater in cells incubated in the presence than in the absence of 0.5 M-NaCl. An approximate 70% removal of external Cs{sup +} resulted after 15 h incubation of cells with 50 μ;M-CsCl and 0.5 M-NaCl. LiCl also had a stimulatory effect on Cs{sup +} uptake, although mannitol did not. Cs{sup +} influx increased with increasing external NaCl concentration and was maximal between 25-500 mM-NaCl at approximately 4 nmol Cs{sup +} h−1 (10{sup 6} cells){sup −1}. Little effect on Cs{sup +} uptake resulted from the presence of Mg{sup 2+} or Ca{sup 2+} or from varying the external pH, and Cs{sup +} was relatively non-toxic towards C. salina. At increasing cell densities (from 4 × 10{sup 5} to 1 × 10{sup 7} cells ml{sup +1}), decreasing amounts of Cs{sup +} were accumulated per cell although the rate of Cs{sup +} removal from the external medium was still greatest at the higher cell densities examined. Freely suspended C. salina and cell-loaded alginate microbeads accumulated similar levels of Cs{sup +}, however, 46% of total Cs{sup +} uptake was attributable to the calcium-alginate matrix in the latter case. When Cs{sup +}-loaded cells were subjected to hypoosmotic shock, loss of cellular Cs{sup +} occurred allowing easy Cs{sup +} recovery. This loss exceeded 90% of cellular Cs{sup +} when cells were washed with solutions containing ≤ 50 mM-NaCl between consecutive Cs{sup +} uptake periods; these cells subsequently lost their ability to accumulate large amounts of Cs{sup +}. Maximal Cs{sup +} uptake (approximately 85.1% removal after three 15 h incubations) occurred when cells were washed with a solution containing 500 mM-NaCl and 200 mM-KCl between incubations. The relevance of these results to the possible use of C. salina in a salt-dependent biological Cs-removal process is discussed. (author)

  11. A novel use of the caesium-137 technique to estimate human interference and historical water level in a Mediterranean Temporary Pond

    OpenAIRE

    Foteinis, S.; Mpizoura, K.; Panagopoulos, G.; Chatzisymeon, E.; Kallithrakas-Kontos, N.; Manutsoglu, E.

    2014-01-01

    The sustainability of, and the effects of human pressures on, Omalos Mediterranean Temporary Pond (MTP), Chanea, Greece was assessed. The Cs technique was used to identify alleged anthropogenic interference (excavation) in the studied area. It was found that about one third of the ponds bed surface material had been removed and disposed of on the northeast edge, confirming unplanned excavations that took place in the MTP area some years ago. Nonetheless, five years after the excavation, the M...

  12. Crystal structure and dielectric measurements of mixed caesium-ammonium mercury chloride: Cs{sub 0.7}(NH{sub 4}){sub 0.3}HgCl{sub 3}

    Energy Technology Data Exchange (ETDEWEB)

    Kabadou, A.; Hassen, R.B.; Salah, A.B. [Fac. des Sci., Sfax (Tunisia). Lab. de l`Etat Solide; Jouini, T.

    1998-08-01

    The title compound crystallises in the space group P3{sub 2} and has the unit cell dimensions a = 13.295(11) A, c = 9.419(8) A, V = 1441.82(2), Z = 9, D{sub exp} = 4.17, D{sub calc} = 4.153. The structure at room temperature is considered as distorted perovskite tentatively with R = 0.057 and WR{sub 2} = 0.153 for 700 observed reflections. The dielectric permittivity measured in the frequency and temperatures ranges 10{sup 3} to 10{sup 6} Hz and 307 to 613 K, respectively, reveals a transition at T = 449 K. Transport properties in this material appear to be due to the high mobility of NH{sub 4}{sup +} in the tunnels. (orig.) 13 refs.

  13. The whole-body incorporation of radioactive caesium in Switzerland during the last 30 years: a survey of young persons in Geneva and some measurements of Belarusian and Ukrainian children

    International Nuclear Information System (INIS)

    Donath, A.

    1996-01-01

    In a cross-sectional study, at least 40 young men and women about 18 years old (half of each sex) were selected each year, and the body concentration of 137 Cs was measured in a whole-body counter. This radioisotope, with a half-life of 30 years, originates from the atom bomb explosions in the atmosphere, which were stopped in 1963, or from the accident at Chernobyl. The concentrations due to the emissions from this reactor remained below one-third of the values due to atomic bombs. The results in children from Belarus who spent a few weeks in Switzerland in the summer are lower than would have been expected according to the literature from Russia, but correspond to those recently obtained in situ by international scientific teams. 6 refs, 1 fig., 1 tab

  14. Experimental contamination of margaritana margaritifera (L) (a Fresh water bivalve) by caesium 137; Contamination experimentale de margaritana margaritifera (L) (bivalve d'eau douce) par le cesium 137

    Energy Technology Data Exchange (ETDEWEB)

    Foulquier, L.; Bovard, P.; Grauby, A. [Commissariat a l' Energie Atomique, Cadarache (France). Centre d' Etudes Nucleaires

    1966-07-01

    The hydro biological research carried out in the Radio-Ecology Section has led the authors to study some Margaritana sampling stations situated down-stream from the Monts d'Arree nuclear power station. They describe the preservation and contamination methods used for fixing the {sup 137}Cs concentration factors in the case of Margaritana Margaritifera (L). The results of experiments carried out over a period of one hundred days show that the specific activity of the various organs is stabilized after thirty to thirty-five days. The authors have noticed a relatively low adsorption on the shell through the intermediary of micro-organisms, and a strong and rapid absorption in the soft parts. The concentration factors have values, at equilibrium, of around: 9 for the shell, 300 for all the organs, and 38 for the whole animal. A comparison of these results with work published by other authors makes it possible to draw general conclusions concerning the mechanism of {sup 137}Cs fixation by lamellibranch, as well as their capacity of fixation. (author) [French] Les etudes hydrobiologiques effectuees au sein de la Section de Radio-Ecologie ont amene les auteurs a etudier des stations de prelevement de Margaritana en aval de la Centrale Nucleaire des Monts d'Arree. Ils decrivent les methodes de conservation et de contamination utilisees pour l'etablissement des facteurs de concentration du {sup 137}Cs par Margaritana margaritifera (L). Les resultats des experimentations menees pendant cent jours montrent que les activites specifiques de la coquille et des differents organes se stabilisent au bout de trente a trente-cinq jours. Les auteurs constatent une adsorption relativement faible sur la coquille par l'intermediaire des micro-organismes et une absorption forte et rapide dans les parties molles. Les facteurs de concentration se situent, a l'equilibre, autour de: 9 pour la coquille, 300 pour l'ensemble des organes et 38 si l'on considere l'animal total. Cette etude comparee a celles deja effectuees par d'autres auteurs permet de degager des idees generales sur le mode et la capacite de fixation du {sup 137}Cs par les lamellibranches. (auteur)

  15. Radioactivity distribution of the fruit trees ascribable to radioactive fall out (6). Effect of heterogeneity of caesium-137 concentration in soil on transferability to grape trees and fig trees

    International Nuclear Information System (INIS)

    Takata, Daisuke; Yasunaga, Eriko; Tanoi, Keitaro

    2013-01-01

    We examined the effects of the heterogeneity of 137 Cs concentration in soil on transferability to shallow rooted fig and non-shallow rooted grapes. Three-year-old trees were planted into the pots filled with soil changed to the concentration of radioactivity Cs in surface (0 - 5cm) and deep soil (5 - 15cm). Transfer rate of radioactive 137 Cs to plants from the soil was higher in fig than in grapes when grown under the same conditions. In fig trees, transfer rate of radioactive 137 Cs to plants from the soil was higher the plants cultivated under high concentration of 137 Cs in surface soil than in deep soil. (author)

  16. Development, control and counter-measures regarding radioactive caesium in Swedish reindeer after the Chernobyl accident; Utveckling, oevervakning och aatgaerder naer det gaeller radioaktivt cesium i renar efter Tjernobylolyckan

    Energy Technology Data Exchange (ETDEWEB)

    Aahman, Birgitta [Swedish Univ. of Agricultural Sciences, Uppsala (Sweden). Reindeer Husbandry Unit

    2005-10-01

    Since the Chernobyl accident in 1986, monitoring of {sup 137}Cs in reindeer has been made at slaughter, by measuring muscle samples or by direct monitoring of gamma radiation on reindeer carcasses. Carcasses above the accepted limit have been discarded. Many carcasses were discarded during the first years, but now the number is only some per cent of the total slaughter. The radiocaesium intake in reindeer varies with season, which is reflected in the levels in reindeer, which are low in summer and high in winter. The levels of {sup 137}Cs have declined from 1986 to 2004 with an average effective half-life of 5.3 years. The decline was faster during the first years than during later years. Presently, 16 out of totally 51 reindeer herding districts in Sweden are included in the control of {sup 137}Cs in reindeer. Control is often necessary only in defined areas or at certain periods of the year. Monitoring of {sup 137}Cs in live reindeer is made in addition to the monitoring at slaughter. Counter-measures have been applied in areas where many reindeer are above the accepted limit for {sup 137}Cs. Change of slaughter time and feeding are the most used counter-measures. The reindeer owners are compensated economically from the state for costs related to these counter-measures. The need for measures, and thereby the costs, have decreased with time. In the southern parts of the county of Vaesterbotten and in the northernmost part of Jaemtland, where the Chernobyl fallout was the highest, it will probably still take at least ten to twenty years until measures and control are no longer needed.

  17. Soil and grass contamination with cesium in South Germany and the winter feed 1986/1987. Die Caesium-Boden- und Graskontamination in Sueddeutschland und die Winterfuetterung 1986/1987

    Energy Technology Data Exchange (ETDEWEB)

    Schmidt, M; Giegrich, J; Franke, B

    1986-01-01

    The data for soil and grass contamination with Cs-137 and Cs-134 by the nuclear accident in Chernobyl have been analyzed for the two federal states of Baden-Wuerttemberg and Bavaria. Large regional variations have been determined, with peak values for ground activity of 36,000 Bq/m/sup 2/ in Southern Bavaria and of 24,000 Bq/m/sup 2/ in the South-East of Baden-Wuerttemberg. The average grass contamination in Baden-Wuerttemberg varied between 170 Bq and 620 Bq per kg fresh weight. The grass contamination in Bavaria was estimated between 200 and 1,000 Bq/kg. Due to the large amount of radioactivity in grass, high quantities of contaminated hay and silage will be used for winter cattle feed and thus will be found in milk and meat products from Southern Germany. Over the 6 winter months, a total of 15.10/sup 12/ Bq Cs-137 will be fed to cattle. This would lead to a calculated average milk concentration of Cs-137 of 250 Bq/l in Bavaria and of 120 Bq/l in Baden-Wuerttemberg.

  18. Dispersal of the radionuclide caesium-137 (137Cs) from point sources in the Barents and Norwegian Seas and its potential contamination of the Arctic marine food chain: Coupling numerical ocean models with geographical fish distribution data

    International Nuclear Information System (INIS)

    Heldal, Hilde Elise; Vikebø, Frode; Johansen, Geir Odd

    2012-01-01

    Dispersal of 137 Cs from Komsomolets and K-159 is simulated using realistic rates and hypothetical scenarios. Furthermore, spatiotemporal 137 Cs concentrations in Northeast Arctic cod and capelin are estimated based on survey data. The results indicate that only pulse discharges from K-159 will cause concentrations of 137 Cs in cod muscle exceeding the intervention level of 600 Bq/kg fresh weight. A discharge of ≥10% of the 137 Cs-inventory will result in concentrations in muscle of cod exceeding the intervention level for approximately two years. In fact, a discharge of 10% of the 137 Cs-inventory results in an overlap of 8–30% between the different size groups of cod and levels that exceed the intervention level during the first year after the discharge. For capelin, individuals less than one year old during the first year after a discharge are more likely to be severely affected by discharges comprising ≥50% of the inventory. - Highlights: ► The dispersal of 137 Cs from the wrecks of Komsomolets and K-159 are simulated. ► The submarine wrecks are resting on the seabed in the Norwegian and Barents Seas. ► Both realistic rates of discharges and what-if scenarios are simulated. ► Concentrations of 137 Cs are estimated in observational records of cod and capelin. ► Only pulse discharges from K-159 causes high 137 Cs concentrations in cod and capelin. - A leakage of 137 Cs from K-159 may cause concentrations in muscle of cod exceeding the intervention level of 600 Bq/kg fresh weight for up to two years after the leakage.

  19. Dispersal of the radionuclide caesium-137 (137Cs) from point sources in the Barents and Norwegian Seas and its potential contamination of the Arctic marine food chain: Coupling numerical ocean models with geographical fish distribution data

    International Nuclear Information System (INIS)

    Heldal, Hilde Elise; Vikebø, Frode; Johansen, Geir Odd

    2013-01-01

    Dispersal of 137 Cs from the nuclear submarine wrecks Komsomolets and K-159, which are resting on the seabed in the Norwegian and Barents Seas, respectively, is simulated using realistic rates and hypothetical scenarios. Furthermore, spatiotemporal 137 Cs concentrations in Northeast Arctic cod and capelin are estimated based on survey data. The results indicate that neither continuous leakages nor pulse discharges will cause concentrations of 137 Cs in cod muscle or whole body capelin exceeding the intervention level of 600 Bq/kg fw. Continuous leakages from Komsomolets and K-159 and pulse discharges from Komsomolets induced negligible activity concentrations in cod and capelin. A pulse discharge of 100% of the 137 Cs-inventory of K-159 will, however, result in concentrations in muscle of cod of above 100 times the present levels in the eastern Barents Sea. Within three years after the release, 137 Cs levels above 20 Bq/kg fw in cod are no longer occurring in the Barents Sea. -- Highlights: •The dispersal of 137 Cs from the wrecks of Komsomolets and K-159 are simulated. •The submarine wrecks are resting on the seabed in the Norwegian and Barents Seas. •Both realistic rates of discharges and what-if scenarios are simulated. •Concentrations of 137 Cs are estimated in observational records of cod and capelin. •Only pulse discharges from K-159 causes high 137 Cs concentrations in cod and capelin. -- A pulse discharge of 137 Cs from K-159 may cause concentrations in muscle of cod up to 63 and 123 Bq/kg fresh weight in the near-surface and near-bottom layer, respectively

  20. Non cancerous diseases following a chronic intern contamination by caesium 137: cataracts and cardiac arrhythmias; Pathologies non cancereuses potentiellement consecutives a une contamination interne chronique par le cesium 137: cataractes et arythmies cardiaques

    Energy Technology Data Exchange (ETDEWEB)

    Landon, G

    2008-07-15

    This work of thesis joins within the framework of an analysis of the sanitary consequences of the nuclear accident of Chernobylsk. Since 2005, the I.R.S.N. is interested in the not cancerous pathologies (cataracts, and cardiac arrhythmias) observed among the children living on the contaminated territories after the fallout of Chernobylsk and has in this aim implemented a research programme called E.P.I.C.E. (Evaluation of the pathologies induced by a chronicle contamination by cesium) whom objective is to show an eventual link between the chronicle ingestion of contaminated food and these pathologies emergence. An exploitation of the results of the pilot study,first phase of the E.P.I.C.E. program was realized. The analysis was completed by two bibliographical reviews relative to the knowledge available on these diseases. The results of this pilot study suggest: on one hand, an absence of link between the activity in cesium 137 at the level of the heart, of the whole body and the emergence of disorder of the heart rhythm; on the other hand, for the cases of cataract, a link between the load in cesium 137 at the neck level and the emergence of the disease in 40 % of the cases. However, these results must be considered with caution because several limits and, in particular, a way of selection affect this study. concerning the scientific literature, this one stays rather poor because only thee articles make reference to a relationship between cesium 137 and the emergence of these non cancerous pathologies. After having exposed the context, this thesis draws up the situation of knowledge relative to cataracts and to cardiac arrhythmias and their possible relationship with ionizing radiations, collect the results stemming from the analysis of the pilot study and envisages future epidemiological studies. (N.C.)

  1. Dispersal of the radionuclide caesium-137 (137Cs) from point sources in the Barents and Norwegian Seas and its potential contamination of the Arctic marine food chain: coupling numerical ocean models with geographical fish distribution data.

    Science.gov (United States)

    Heldal, Hilde Elise; Vikebø, Frode; Johansen, Geir Odd

    2012-05-01

    Dispersal of (137)Cs from Komsomolets and K-159 is simulated using realistic rates and hypothetical scenarios. Furthermore, spatiotemporal (137)Cs concentrations in Northeast Arctic cod and capelin are estimated based on survey data. The results indicate that only pulse discharges from K-159 will cause concentrations of (137)Cs in cod muscle exceeding the intervention level of 600 Bq/kg fresh weight. A discharge of ≥10% of the (137)Cs-inventory will result in concentrations in muscle of cod exceeding the intervention level for approximately two years. In fact, a discharge of 10% of the (137)Cs-inventory results in an overlap of 8-30% between the different size groups of cod and levels that exceed the intervention level during the first year after the discharge. For capelin, individuals less than one year old during the first year after a discharge are more likely to be severely affected by discharges comprising ≥50% of the inventory. Copyright © 2012 Elsevier Ltd. All rights reserved.

  2. Dispersal of the radionuclide caesium-137 ((137)Cs) from point sources in the Barents and Norwegian Seas and its potential contamination of the Arctic marine food chain: coupling numerical ocean models with geographical fish distribution data.

    Science.gov (United States)

    Heldal, Hilde Elise; Vikebø, Frode; Johansen, Geir Odd

    2013-09-01

    Dispersal of (137)Cs from the nuclear submarine wrecks Komsomolets and K-159, which are resting on the seabed in the Norwegian and Barents Seas, respectively, is simulated using realistic rates and hypothetical scenarios. Furthermore, spatiotemporal (137)Cs concentrations in Northeast Arctic cod and capelin are estimated based on survey data. The results indicate that neither continuous leakages nor pulse discharges will cause concentrations of (137)Cs in cod muscle or whole body capelin exceeding the intervention level of 600 Bq/kg fw. Continuous leakages from Komsomolets and K-159 and pulse discharges from Komsomolets induced negligible activity concentrations in cod and capelin. A pulse discharge of 100% of the (137)Cs-inventory of K-159 will, however, result in concentrations in muscle of cod of above 100 times the present levels in the eastern Barents Sea. Within three years after the release, (137)Cs levels above 20 Bq/kg fw in cod are no longer occurring in the Barents Sea. Copyright © 2013 Elsevier Ltd. All rights reserved.

  3. The study of sorption of cesium radionuclides by 'T-55' ferrocyanide sorbent from various types of liquid radioactive wastes

    International Nuclear Information System (INIS)

    Semenischev, V.S.; Voronina, A.V.; Bykov, A.A.

    2013-01-01

    The sorption of caesium by T-55 sorbent from different types of liquid radioactive wastes is studied. It is shown that the sorbent can be used for extraction of cesium from high level acidic and saline solutions and also for decontamination of caesium contaminated waters containing surfactants and EDTA. (author)

  4. Studies of radiocaesium migration in soils with high organic matter content

    International Nuclear Information System (INIS)

    Zygmunt, J.; Chibowski, S.; Klimowicz, Z.

    1997-01-01

    This paper encloses results of field tests carried out on two types of organic soils. Activities of caesium, originating from global fallout as well as from Chernobyl power plant breakdown, were measured for these two soils. Radioactive caesium is present to a depth of 40 and 70 cm, in black soil and in peat, respectively, although the highest activity was found in the topmost layers. Caesium originating from the Chernobyl accident constitutes about 70% of the total activity in the 0-10 cm layers of soils. The vertical migration rates of caesium from both sources were also measured. In the case of peat soil the migration rate of the Chernobyl caesium as well as that from global fallout were found to be similar and amounted to 0.2 cm/year. In the case of black soil the differences were more pronounced (0.34 and 0.14 cm/year, respectively). (author)

  5. Removal of active species from liquid effluent

    International Nuclear Information System (INIS)

    Blake, N.J.; Ritchie, S.

    1992-01-01

    Experimental and theoretical assessments were made of recirculating liquid membrane technology applied to the removal of active species from liquid effluent. Caesium and strontium were extracted from neutral, aqueous liquor by di-(2-ethylhexyl) phosphate in odourless kerosine and subsequently stripped by nitric acid. Flowrates to the membrane modules influenced the extraction and stripping mass transfer coefficients (MTC) for caesium, but not strontium. The acid strength of the strip solution affected the stripping MTC. When both ions were co-processed, caesium transfer was retarded. Potassium cobalt ferrocyanide and polyantimonic acid were used as adsorbers for caesium and strontium respectively in the strip loop. Caesium was more quickly adsorbed than strontium. A scale-up assessment of a recirculating liquid membrane was performed and compared to SIXEP at Sellafield. (author)

  6. Delayed and late impact of the Chernobyl accident on the Greek environment

    Energy Technology Data Exchange (ETDEWEB)

    Kritidis, P.; Papanicolaou, E. (National Centre for Scientific Research ' Democritos' , Athens (Greece)); Florou, H. (National Centre for Marine Research, Athens (Greece))

    1990-01-01

    The impact of the Chernobyl nuclear accident on the Greek environment during and after the winter 1986-87 and the estimated long-term doses to the population are discussed. This includes the delayed peak of caesium concentrations observed in animal products, the contamination of pastry and bread, the additional external exposure in areas of peak caesium deposition, the soil-to-plant transfer of caesium, the contamination of marine and lake fish and the residual contamination in air, deposition and surface waters. (author).

  7. Delayed and late impact of the Chernobyl accident on the Greek environment

    International Nuclear Information System (INIS)

    Kritidis, P.; Papanicolaou, E.; Florou, H.

    1990-01-01

    The impact of the Chernobyl nuclear accident on the Greek environment during and after the winter 1986-87 and the estimated long-term doses to the population are discussed. This includes the delayed peak of caesium concentrations observed in animal products, the contamination of pastry and bread, the additional external exposure in areas of peak caesium deposition, the soil-to-plant transfer of caesium, the contamination of marine and lake fish and the residual contamination in air, deposition and surface waters. (author)

  8. Analysis of postoperative vaginal vault radiotherapy of stage I endometrial cancer with different radionuclides

    International Nuclear Information System (INIS)

    Ryberg, M.; Einhorn, N.; Hamed, A.F.A.; Ruden, B.I.; Nilsson, B.

    1998-01-01

    A total of 213 patients in stage I grade 1 endometrical cancer were treated postoperatively with either radium or caesium vaginal applicators. The rate of complication and the incidence of second malignancies were studied in both groups. The frequency of grades 2 and 3 vaginal complications was higher among patients treated with caesium applicators but not statistically significant. The observed number of second malignancies was significantly higher than expected in the radium-treated group, in which the observed number of second malignancies with distant location was also significantly higher than expected, which could not be found in the caesium group. (orig.)

  9. Transport processes of Cs-137 in lake environments

    International Nuclear Information System (INIS)

    Hilton, J.; Carrick, T.R.; Lishman, J.P.; Rigg, E.; Davison, W.; Kelly, M.; Hamilton-Taylor, J.

    1992-01-01

    Radiocesium levels in the waters of the Lake District dropped after the initial deposition following the Chernobyl reactor accident. However they continued to be measurable several years after the event. Caesium 137 concentrations were measured in the sediments of Esthwaite water and Windermere to determine the input of caesium 137 from the catchment area to the lakes. Experiments were conducted to ascertain the chemical conditions such as pH value, adsorption, competing ions which might contribute to maintaining caesium levels in the lakes. (U.K.)

  10. Analytical application of thiosulfatobismuthates(3)

    International Nuclear Information System (INIS)

    Kobylecka, J.; Cyganski, A.

    1980-01-01

    The analytical application of caesium-sodium thiosulfatobismuthate(3) is presented. Gravimetric, compleximetric and thermal methods of caesium determination have been developed. The gravimetric method is based on precipitation of caesium as Cs 2 Na[Bi(S 2 O 3 ) 3 ], filtration and desiccation of precipitate at about 100 0 C. In compleximetric procedure the precipitate was dissolved in nitric acid and bismuth was titrated by EDTA solution. In thermal method the precipitate was heated up to 320 0 C while the released sulphur dioxide was absorbed by sodium terachloromercurate and formed acid was determined alkalimetrically. The described rapid methods have a satisfactory precision and accuracy. (author)

  11. Cs separation from nitric acid solutions of radioactive waste

    International Nuclear Information System (INIS)

    Heckmann, K.; Pieronczyk, W.; Strnad, J.; Feldmaier, F.

    1989-01-01

    It was the objective of this study to selectively separate active caesium (Cs-134 and Cs-137) from acid radioactive waste solutions (especially MAW and HAWC). The following 'strategy' was designed for a separation process: synthesis of reagents which are acid-resistant and selective for caesium; precipitation of Cs + and separation of the precipitates by filtration or centrifugation or precipitation of Cs + and separation of the precipitates by flotation; caesium separation by liquid-liquid extraction. As precipitating agents, sodium tetraphenylborate (kalignost) and several of its fluorine derivatives were examined. (orig./RB) [de

  12. Applicability and reliability of the 'observed ratio' model as a means of describing the strontium and the cesium transfer from soil to plant. Eignung und Zuverlaessigkeit des 'observed ratio' Modells fuer die Beschreibung des Strontium- und Caesium-Transfers vom Boden in die Pflanze

    Energy Technology Data Exchange (ETDEWEB)

    Leising, C.

    1986-12-01

    The report examines the suitability of the observed ratio, (OR), model as a means of describing the soil-to-plant transfer of cesium and strontium, and the reliability of results determined by this model. Literature studies have been made and are reported in order to show the discrimination between Sr and Ca, or Cs and K, respectively, and in order to show the magnitude of the OR value and the range of values it may cover. For the evaluation of results, care has been taken that only the physiologically relevant constituents of Sr, Ca, Cs, and K concentrations in the soil are taken into account, which are the water-soluble and the adsorptively bound forms. Non-mobile forms cannot be taken up by the plant and therefore are not considered in the model. In accordance with the literature reviewed, the report also differentiates between two experimental approaches: (1) hydroponics, and (2) greenhouse or field experiments.

  13. Literature study of the radiobiological parameters of Caesium-137 required for evaluating internal irradiation doses as a function of age; Etude bibliographique des parametres radiobiologiques du cesium-137 necessaires a l'evaluation des doses d'irradiation interne en fonction de l'age

    Energy Technology Data Exchange (ETDEWEB)

    Garnier, A [Commissariat a l' Energie Atomique, 92 - Fontenay-aux-Roses (France). Centre d' Etudes Nucleaires

    1968-07-01

    This document reassembles information published in scientific literature on radiobiological parameters of Cs-137, necessary for the estimate of the internal irradiation dose of man according to his age (during growth). The data are completed by a commented review of the mathematical models, proposed in order to value the irradiation doses from ingested cesium and the biological parameters. (author) [French] Ce document rassemble les informations publiees dans la litterature scientifique, concernant les parametres radiobiologiqueo du cesium-137, necessaires a l'evaluation des doses d'irradiation interne de l'homme en fonction de l'age. Ces donnees sont completees par une revue commentee des modeles mathematiques proposes en vue de l'evaluation des doses d'irradiation a partir des quantites de cesium ingerees et des parametres biologiques. (auteur)

  14. Literature study of the radiobiological parameters of Caesium-137 required for evaluating internal irradiation doses as a function of age; Etude bibliographique des parametres radiobiologiques du cesium-137 necessaires a l'evaluation des doses d'irradiation interne en fonction de l'age

    Energy Technology Data Exchange (ETDEWEB)

    Garnier, A. [Commissariat a l' Energie Atomique, 92 - Fontenay-aux-Roses (France). Centre d' Etudes Nucleaires

    1968-07-01

    This document reassembles information published in scientific literature on radiobiological parameters of Cs-137, necessary for the estimate of the internal irradiation dose of man according to his age (during growth). The data are completed by a commented review of the mathematical models, proposed in order to value the irradiation doses from ingested cesium and the biological parameters. (author) [French] Ce document rassemble les informations publiees dans la litterature scientifique, concernant les parametres radiobiologiqueo du cesium-137, necessaires a l'evaluation des doses d'irradiation interne de l'homme en fonction de l'age. Ces donnees sont completees par une revue commentee des modeles mathematiques proposes en vue de l'evaluation des doses d'irradiation a partir des quantites de cesium ingerees et des parametres biologiques. (auteur)

  15. Radioactive contamination in reindeer herders and other people in Kautokeino 1965-2010

    International Nuclear Information System (INIS)

    Thoerring, H.; Skuterud, L.

    2012-01-01

    NRPA's measurements of radioactive caesium in reindeer herders and other people from Kautokeino in northern Norway were finalised in December 2010. This report summarises the monitoring program which was started in 1965.(Author)

  16. Improvement of practical countermeasures: the urban environment post-Chernobyl action

    International Nuclear Information System (INIS)

    Sinnaeve, J.; Olast, M.

    1991-01-01

    This study of practical countermeasures against nuclear contamination of the urban environment in the aftermath of a nuclear accident concentrates almost entirely on radio-caesium, which would be expected to pose the greatest threat to the population in the medium and long term. Surfaces which selectively absorb caesium fall-out were identified, and the chemical and physical factors relevant to take-up of caesium by, and removal of caesium from, these surfaces were studied. The study includes a critical review of strategies for decontamination and reclamation of the urban environment. The work in this report was sponsored by the Commission of the European Communities as one of a series of post-Chernobyl actions under its radiation protection programme

  17. Facile synthesis and characterization of CsPbBr3 and CsPb2Br5 ...

    Indian Academy of Sciences (India)

    2018-03-23

    Mar 23, 2018 ... All-inorganic caesium lead-halide perovskite CsPbBr3 and ... optoelectronic materials owing to their stabilities and highly efficient photoluminescence (PL). ... chemical tenability [2], hybrid organic–inorganic lead halide-.

  18. Ten years after the radiological accident of Goiania, a reflection

    International Nuclear Information System (INIS)

    Nouailhetas, Y.; Xavier, A.M.

    1998-01-01

    This work contains a reflection on the impact of the radiological protection measures taken in the city of Goiania in the aftermath of the accident involving caesium-137, along with a discussion on the biological foundation of these actions. (author)

  19. The determination of radiocaesium in sea and fresh waters

    International Nuclear Information System (INIS)

    Baker, C.W.

    1975-10-01

    The caesium is adsorbed on to a cartridge of silica gel impregnated with ammonium molybdophosphate from 50 litres of filtered water, adjusted to pH 2 with nitric acid. The cartridge is then placed in a well crystal detector and gamma counted. An additional separation step is required if zirconium-95/niobium-95 contamination has occurred, as shown by gamma spectrometric analysis of the cartridge. The measurement of caesium-137 and caesium-134 is by conventional γ-spectrometry. The output of the analysing system is ASCII paper tape, and a PDP-8 computer is used to convert this spectral information to activity of caesium-137 and -134 in pCi l -1 at the time of sample collection. (U.K.)

  20. Radioactivity in Scottish soils and grassy vegetation

    International Nuclear Information System (INIS)

    Miller, G.R.; Horrill, A.D.; Thomson, A.J.; Howson, G.

    1989-05-01

    In June 1987, soil and graminoid vegetation samples were collected from 159 randomly selected Scottish sites and analysed for radioactivity due to potassium-40, caesium-134 and caesium-137. Activity due to plutonium-238 and plutonium-239/240 was also measured in soils from 47 of the sites. The main aims of this survey were to determine: (a) the geographic distribution of radiocaesium activity due to fallout from the Chernobyl reactor disaster, (b) the pattern of radiation due to the naturally occurring isotope potassium-40, (c) the activity attributable to caesium-137 fallout from nuclear weapons testing prior to the Chernobyl deposition, (d) the uptake of caesium-137 by vegetation from different soil types. (author)

  1. Radioactive contamination in reindeer herders and other people in Kautokeino 1965-2010; Radioaktiv forurensning i befolkningen. Reindriftsutoevere og andre personer i Kautokeino 1965-2010

    Energy Technology Data Exchange (ETDEWEB)

    Thoerring, H.; Skuterud, L.

    2012-07-01

    NRPA's measurements of radioactive caesium in reindeer herders and other people from Kautokeino in northern Norway were finalised in December 2010. This report summarises the monitoring program which was started in 1965.(Author)

  2. On the Power Dependence of Extraneous Microwave Fields in Atomic Frequency Standards

    Science.gov (United States)

    2005-01-01

    uncertainty”, Metrologia 35 (1998) pp. 829-845. [6] K. Dorenwendt and A. Bauch, “Spurious Microwave Fields in Caesium Atomic Beam Standards...Cesium Beam Clocks Induced by Microwave Leakages”, IEEE Trans. UFFC 45 (1998)728-738. [8] M. Abgrall, “Evaluation des Performances de la Fontaine...Proc of the EFTF 2005 – in press. [12] A. DeMarchi, “The Optically Pumped Caesium Fountain: 10-15 Frequency Accuracy?”, Metrologia 18 (1982) pp

  3. The environmental chemistry of radiocaesium and other nuclides

    International Nuclear Information System (INIS)

    Oughton, D.H.

    1989-02-01

    This thesis reports studies on the environmental chemistry of radiocaesium, and is related particularly to upland ecosystems and grazing animals. The underlying philosophy of this thesis is that fallout radiocaesium will act as a tracer for naturally occuring stable caesium. Therefore, investigations into radiocaesium distribution and mobility within environmental and biological systems are complemented by studies of the stable caesium concentrations and transfer mechanisms within that ecosystem. (author)

  4. Comparisons of the emissions in the Windscale and Chernobyl accidents

    International Nuclear Information System (INIS)

    Chamberlain, A.C.

    1987-02-01

    The contents are summarized under the following headings: 1) Windscale accident summary 2) Emission of 137 Cs from Windscale 3) Emission of other fission products from Windscale 4) Environmental effects - iodine 5) Environmental effects - caesium. A bibliography is attached and where figures are available, comparisons are made with the Chernobyl fallout, including thyroid iodine burdens for U.K. students who were in Russia at the time of the Chernobyl accident, and milk measurements of Caesium 137 in the U.K. (UK)

  5. Radioactivity monitoring of the Irish marine environment 1987

    International Nuclear Information System (INIS)

    O'Grady, J.; Currivan, L.

    1990-06-01

    This report represents the results of the Board's monitoring of radioactivity levels in the Irish marine environment during 1987. The principal objective of the monitoring programme is to obtain estimates of radiation doses to the Irish public arising from caesium-137 and caesium 134, the main contaminating radionuclides. Estimates are presented of the radiation doses to the Irish public arising from the consumption of fish and shellfish contaminated with radiocaesium

  6. Apparatus and method for generating high density pulses of electrons

    International Nuclear Information System (INIS)

    Lee, C.; Oettinger, P.E.

    1981-01-01

    An apparatus and method are described for the production of high density pulses of electrons using a laser energized emitter. Caesium atoms from a low pressure vapour atmosphere are absorbed on and migrate from a metallic target rapidly heated by a laser to a high temperature. Due to this heating time being short compared with the residence time of the caesium atoms adsorbed on the target surface, copious electrons are emitted which form a high current density pulse. (U.K.)

  7. Preliminary assessment of the potential for using cesium-137 technique to estimate rates of soil erosion on cultivated land in La Victoria I, Camaguey province of cuba

    International Nuclear Information System (INIS)

    Brigido, F.O.; Gandarilla Benitez, J.E.

    1999-01-01

    Despite a growing awareness that erosion on cultivated land in Cuba is a potential hazard to long term productivity, there is still only limited information on the rates involved, particularly long term values. The potential for using the radionuclide Caesium-137 as an environmental tracer to indicate sources of soil erosion on cultivated soils in La Victoria catchment is introduced. Use of Caesium-137 measurements to estimate rates of erosion and deposition is founded on comparison of the Caesium-137 inventories at individual sampling points with a reference inventory representing the local Caesium fallout input and thus the inventory to be expected at the site experiencing neither erosion nor deposition. Two models for converting Caesium-137 measurements to estimates of soil redistribution rates on studied site have been used, the Proportional Model and Mass Balance Model. Using the first one net soil erosion was calculated to be 17.6 t. Ha 1 - .year 1 - . Estimates of soil loss using a Mass Balance Model (Simplified Model 1 and Model 2) were found to be 30.2 and 30.6 t. Ha 1 - .year 1 - ,respectively. Preliminary results suggest that Caesium-137 technique may be of considerable value in assembling data on the rates and spatial distribution of soil loss and a reliable tool for developing of soil conservation program

  8. Honey-dew honey as a long term indicator of 137Cs pollution

    International Nuclear Information System (INIS)

    Kezic, N.; Hus, M.; Seletkovic, Z.; Kraljevic, P.; Pechhacker, H.; Barisic, D.; Lulic, S.; Vertacnik, A.

    1997-01-01

    137 Cs, produced as a by-product of the atmospheric testing of thermonuclear weapons during the period extending from the 1950s to the 1970s, was distributed globally within the stratosphere and deposited as wet and/or dry fallout. The last great amount of radioactive caesium was deposited on the earth surface after Chernobyl accident. Significant variations in caesium activity levels in soils are caused by Chernobyl-derived fallout with relatively short period of contamination and great variabilities in activity and/or quantity of rainfall. However, total weapon testing-derived caesium pollution can be treated as generally uniform, i.e., numerous events over an extended period that minimise any local variation. Meanwhile, caesium, as well as the other radionuclides that behave like cations, can be moved upward by plant's uptake depending on various factors: plant species, sorption and desorption processes in soil, mineral soil composition, grain size and soil types, lateral caesium migration, etc. Certain plant species are known as caesium pollution indicators, but the uptake by an individual plant can be very different

  9. Radioactivity of the environment and food in Poland in 1986-1990

    International Nuclear Information System (INIS)

    Grabowski, D.; Jankowska, S.; Muszynski, W.; Petrykowska, M.; Rubel, B.

    2004-01-01

    The Chernobyl accident caused the growth of the radioactive contamination of the environment and foodstuffs in Poland as compared with the pre-accident situation. The level of this contamination was not yet so high, to consider the intake dose of the Polish population as the substantial hazard. In the first month after Chernobyl accident the significant values attained the iodine isotopes contamination, especially iodine 131. Later on the higher level of caesium isotopes contamination was noticed only. This level of contamination is decreasing distinctly. This paper provides the results of environment and foodstuffs contamination measurements. In order to estimate the effective dose equivalent for Polish population the caesium content of the diet have been calculated and analysed. The results of the studies showed that the effective dose equivalent in the first year after the accident was nearly 0.3 mSv and in the next years 0.04 mSv and 0.02 mSv. The level of effective dose equivalent depends of isotopes ingested via foodstuff consumption. In the first year there were: iodine 131, caesium 134 and caesium 137, later on the caesium isotopes only. In the contamination of average annual diet the greatest part consist of milk consumption. (author)

  10. Crystal structure of (acetato-κO(ethanol-κO[(9S,17S,21S,29S-9,17,21,29-tetrahydroxy-18,30-dioxaoctacyclo[18.10.0.02,7.08,19.09,17.011,16.021,29.023,28]triaconta-1,3,5,7,11(16,12,14,19,23(28,24,26-undecaene-10,22-dione-κ3O18,O21,O22]caesium ethanol monosolvate

    Directory of Open Access Journals (Sweden)

    Ravell Bengiat

    2016-07-01

    Full Text Available The title compound, [Cs(CH3COO(C28H16O8(C2H5OH]·C2H5OH, is the product of the complexation between one vasarene analogue [1], bis ninhydrin naphthalene-1,3-diol and CsF, where the F− ion has reacted with residual acetic acid (AcOH, to form a [1]·CsOAc complex. The intermolecular interactions with the multiple oxygen-containing functional groups of the ligand, as well as O—H...O hydrogen bonds involving the ethanol solvent molecules, stabilize the complex, forming a chain along [100]. Additional parallel-displaced π–π stacking, with an interplanar distance of 3.669 (1 Å, connect several unit cells in a three-dimensional supramolecular structure, though, the larger size of AcO− (1.60 Å compared to F− (1.33 Å prevents the tight packing that was once achieved with other vasarene complexes of CsF.

  11. Radionuclide transfer from forage plants into milk

    Energy Technology Data Exchange (ETDEWEB)

    Heeschen, W

    1987-06-09

    There is a lot of information regarding the transfer of radionuclides (iodine, caesium, strontium) which allows the transfer factor being calculated with high certainty. The transfer coefficients (forage-)plant/milk laid down in Paragraph 45 of the Radiation Protection Ordinance (Strahlenschutzverordnung) amount to 1.0x10/sup -2/ for iodine-131, 1.2x10/sup -2/ for caesium-137 and 2.0x10/sup -3/ for strontium-90. More recent calculated factors are markedly lower at the average. During milk processing, the greatest amount of radionuclides gets access to the whey or into the permeate after ultrafiltration of whey. In butter and cheese only minute amounts of caesium can be expected.

  12. Effect of Different Decorporating Agents on the Whole Body Retention of Radioisotopes

    International Nuclear Information System (INIS)

    Gachalyi, A.; Furesz, J.; Gyulai, G.

    2001-01-01

    Full text: Internal contamination of persons working in nuclear industry and laboratories or living near such establishments may occur as a result of single or repeated exposures to radionuclides. Some of the population that might ingest radionuclides could also be expected to receive substantial doses of external (mainly gamma-rays and/or neutrons) radiation. Among the fission products forming in nuclear reactions strontium, niobium, caesium, rare earths and plutonium play an important role when they are released into the environment as well as most important from the standpoint of radiological protection. The Personal Decontamination (First-Aid) Kit was developed for emergency treatment of personnel contaminated by inhalation or ingestion with iodine, strontium, caesium, rare earths, plutonium, transplutonics, and a mixture of fission products as well as for decontamination of contaminated wounds with these substances. We have investigated the toxicological properties, deposition and elimination characteristics of these radionuclides (for example: strontium, caesium, cerium) in animals experiments. (author)

  13. Effects of food processing on the radioactivity of vegetables and cereals

    International Nuclear Information System (INIS)

    Roussel-Debet, S.; Real, J.

    1995-01-01

    The decrease of radioactivity for 134 Cs, 85 Sr, 106 Ru, 57 Co, 110m Ag during food processing was measured. Washing and bleaching vegetables directly contaminated by a single aerosol deposit led to a radioactivity decrease (depending on the vegetable, the radionuclide and the time of deposition) up to 90% for caesium. The efficiency of these processes was less important when the vegetables were contaminated by root transfer, except for peeling of root vegetables. Canning of vegetables indirectly contaminated by caesium, strontium, cobalt and ruthenium, after paring and bleaching, was rather interesting with residual radioactivity varying from 30 to 50% for green beans and from 5 to 20% for carrots. Measurements of stable caesium and strontium in cereals before and after industrial processing showed an important activity decrease; retention factors varied from 0.1 to 0.2 for wheat milling and 0.1 to 0.4 for rice processing. (authors). 6 refs., 9 tabs., 1 figs

  14. Synthesis of derivatives of tetronic acid and pulvinic acid. Total synthesis of norbadione A

    International Nuclear Information System (INIS)

    Mallinger, A.

    2008-11-01

    When vegetables like mushrooms are contaminated by radioactive caesium 137, this radioactive caesium is associated to norbadione A, a natural pigment present in two mushroom species and which can be used as a caesium decorporation agent or maybe as protection agent against ionizing radiations. Within this perspective, this research report describes the biosynthesis and the structure and properties of the norbadione A and of pulvinic acids (physicochemical properties, anti-oxidizing properties). Then, it presents the various tetronic acids (3-acyl-, 3-alkyl-, 3-alkoxy-, 3-aryl-tetronic acids and non 3-substituted tetronic acids), their synthesis path as they are described in the literature, and presents a new synthesis approach using a tandem reaction (with different esters or hydroxy esters) and the synthesis of tetronic acids. The author also proposes a new synthesis way for methyl pulvinates, and finally reports the work on the development of a total synthesis of the norbadione A

  15. How are radioactive deposits redistributed among watersheds in post-accidental situations? Lessons learned from the Chernobyl and Fukushima accidents

    International Nuclear Information System (INIS)

    2016-03-01

    As radioactive releases in the atmosphere resulted in heterogeneous deposits on large continental surfaces including forests, farming lands and residential areas, water runoff in contaminated areas governs the downstream redistribution of caesium 134 and 137. Based on several published studies, this report proposes a synthetic overview of the knowledge of radionuclide flows associated to these processes. The quantity of radio-caesium concerned by watershed washouts has been studied, and appeared to be the result of complex hydrologic and erosive processes. Some studies noticed that, in this respect, the comparison between exported flows in Chernobyl and in Fukushima is difficult because the washout of radio-caesium was essentially solid in Fukushima while liquid in Chernobyl. Thus, the strategy applied for the management of aquatic environments is different

  16. Radioactive contamination of the forests in Southern Poland in the year 1987

    International Nuclear Information System (INIS)

    Jasinska, M.; Mietelski, J.W.; Greszta, J.; Barszcz, J.; Niemtur, S.

    1989-01-01

    Experimental data of caesium and ruthenium radioactivity in chosen parts of forests ecosystems in Southern Poland are presented. Samples were taken from 19 experimental areas placed in the standard net of Academy of Agriculture areas in the summer of 1987. Samples of plants and of two upper layers of forest soil were analysed. Measurements were performed with a low-background gamma-rays spectrometer with the Ge(Li) detector. Caesium and 137 activity (decay corrected for 1 August 1987) in litter reaches 2.5 kBq per kg of dry mass. The correlation factors between contamination levels in various kinds of samples were calculated. Caesium 137 contamination level before Chernobyl accident in moulder layer of soils was estimated. 15 refs., 3 figs., 6 tabs. (author)

  17. Assessment of the radiocaesium levels in irish soils and its transfer to crops

    International Nuclear Information System (INIS)

    MacNeill, Geraldine; Duffy, J.T.; Cunningham, J.D.; Coulter, B.; Diamond, S.; McAulay, I.R.; Moran, D.

    1991-02-01

    The behaviour of radiocaesium deposited by the Chernobyl fall-out was investigated in eleven different permanent pastures and arable lands. Samples of grass and subjacent soil at various depths were collected and analysed for their caesium content during a period extending from the Spring of 1987 (one year after the accident) to the Autumn of 1988. Soil from tillage land along with vegetable and grain crops from this land were also sampled and subjected to gamma spectrometric analysis. The results for the pasture soils show that there has been limited downward migration of Chernobyl caesium. In October 1988 more than 88% of caesium of Chernobyl origin was still retained in the 0-10 cm layer of undisturbed pasture soil. It would also appear that at most sites more than 70% of weapons deposited caesiym is still contained in the 0-15 cm soil layer

  18. Formation of cold molecules through the photo-association of cold atoms of Cesium. Existence of long range forces between between cold excited atoms of Cesium

    International Nuclear Information System (INIS)

    Comparat, D.

    1999-09-01

    This thesis deals with the experimental study and the theoretical interpretation of the processes involved in photo-association and the formation of cold caesium molecules. It also presents a study of the dipolar forces between a pair of cold excited caesium atoms. We present here the first photo-association experiment on cold caesium atoms: two cold atoms absorb a photon to form an excited electronically excited molecules in a rotation-vibration level. The first production of cold molecules which was realised experimentally, after the spontaneous deexcitation of the photo-associated molecules, is described, stressing the role of the potential well of the molecular states O g - (6s+6p 3/2 ) or 1 u (6s+6p 3/2 ) of caesium. The detection of the formed caesium molecules is based on a two-photons resonant ionisation that creates Cs 2 + ions, afterwards selectively detected. Temperatures around 20-200 μK have been measured. The photo-associative spectroscopy is described on the theoretical point of view: a detailed theoretical study allows to calculate precisely the asymptotic parts of the potential curves. On the experimental point of view, we present the spectroscopy of the extern potential well of the caesium state O g - (6s+6p 3/2 ) and the construction of an effective potential curve of the RKR type. A unified theory of photo-association in weak field, considered as a collision assisted by laser, is developed. The cold atoms experiments allow to study and control the collision between two atoms whose mutual interaction is of the dipole-dipole type. Two different physical systems are studied: a sample of Rydberg atoms, and the photo-association process which is a laser-assisted collision. A modification of the motion of one pair of atoms makes it possible to control the bipolar forces and to choose the atoms relative speeds. (author)

  19. Phosphates as packaging materials for separated nuclear wastes

    International Nuclear Information System (INIS)

    Audubert, F.

    2006-10-01

    The author gives an overview of fifteen years of research activities performed within the context of the so-called Bataille bill which recommended in 1991 new investigations on the management of nuclear wastes. She presents studies aimed at the elaboration of phosphates with an apatite structure, and outlines the determination of compositions adapted to iodine, caesium and tri- or tetravalent actinide incorporation. She reports the synthesis of phosphates with a monazite structure for caesium and actinide confinement. Finally, she reports studies dealing with the waste packaging issue (elaboration of packaging matrices, properties)

  20. Radioactive contamination of the forests of southern Poland and Finland

    International Nuclear Information System (INIS)

    Jasinska, H.; Kozak, K.; Mietelski, J.W.; Barszcz, J.; Greszta, J.

    2004-01-01

    Experimental data of caesium and ruthenium radioactivity in chosen parts of forest ecosystems in Finland and Southern Poland are presented and compared. Measurements were performed with a low-background gamma-rays spectrometer with the Ge(Li) detector. The maximum caesium 137 activity in litter from Poland is 2.5 kBq, in that from Finland 3.9 kBq, in spruce needles it is 0.4 kBq (Poland), 0.9 kBq (Finland) and in fern leaves it is as high as 15.9 kBq per kg of dry mass in one sample from Poland. (author)

  1. Treatment of low-level radioactive waste using Volcanic ash

    International Nuclear Information System (INIS)

    Valdezco, E.M.; Marcelo, E.A.; Junio, J.B.; Caseria, E.S.; Salom, D.S.; Alamares, A.L.

    1997-01-01

    The effective application of volcanic ash, an indigenous adsorptive material abundant in the Mt. Pinatubo area, in the removal of radioiodine from radioactive waste streams was demonstrated. Factors such as availability, low cost and comparative retention capacity with respect to activated charcoal make volcanic ash an attractive alternative in the conditioning of radioactive waste containing radioiodine. Chemical precipitation was employed in the treatment of low level aqueous waste containing 137 Cs. It was shown that there exists an optimum concentration of ferric ion that promotes maximum precipitation of caesium. It was further demonstrated that complete removal of caesium can be achieved with the addition of nickel hexacyanoferrate. (author). 5 refs, 3 figs

  2. The treatment of low level effluents by flocculation and settling at the Chooz nuclear power plant

    International Nuclear Information System (INIS)

    Petteau, J.L.; Roofthooft, R.

    1989-01-01

    At the Chooz plant, radioactive effluents were formerly treated by evaporation, but because throughput was low, another method was studied. After laboratory tests, a 500 L/h flocculation and settling pilot plant was constructed, followed later by a 5 m 3 /h installation. The main isotopes eliminated are caesium-134 and caesium-137. Flocculation with copper ferrocyanide reduces the total activity to less than 500 Bq/L. The installation described in the paper was commissioned in 1984 and has been in industrial operation since 1985, processing all types of effluent. The evaporator can be set aside for boric acid recovery. (author). 3 figs, 1 tab

  3. Treatment of low-level radioactive waste using Volcanic ash

    Energy Technology Data Exchange (ETDEWEB)

    Valdezco, E M; Marcelo, E A; Junio, J B; Caseria, E S; Salom, D S; Alamares, A L [Philippine Nuclear Research Inst., Manila (Philippines). Radiation Protection Services

    1997-02-01

    The effective application of volcanic ash, an indigenous adsorptive material abundant in the Mt. Pinatubo area, in the removal of radioiodine from radioactive waste streams was demonstrated. Factors such as availability, low cost and comparative retention capacity with respect to activated charcoal make volcanic ash an attractive alternative in the conditioning of radioactive waste containing radioiodine. Chemical precipitation was employed in the treatment of low level aqueous waste containing {sup 137}Cs. It was shown that there exists an optimum concentration of ferric ion that promotes maximum precipitation of caesium. It was further demonstrated that complete removal of caesium can be achieved with the addition of nickel hexacyanoferrate. (author). 5 refs, 3 figs.

  4. Brazilian bentonite study: use in Goiania; Estudo das bentonitas nacionais: utilizacao em Goiania

    Energy Technology Data Exchange (ETDEWEB)

    Tello, Cledola Cassia Oliveira de [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN), Belo Horizonte, MG (Brazil)

    1997-12-31

    The evaluation of the bentonite effect in the waste cementation process and in the final solidified product properties is presented. The research showed that bentonite amounts until 15% in the product improves the caesium retention without jeopardizing the other product properties. These results were very useful in the treatment of the wastes from the radiological accident occurred in Goiania in 1987, when a caesium sources was broken. Paste, mortar and grout with bentonite were used to solidify and immobilize these wastes. (author) 20 refs., 1 fig., 6 tabs.; e-mail: tellocc at urano.cdtn.br

  5. Sound speed of isobaric heat capacity in the saturated and superheated vapour of cesium, rubidium and potassium

    International Nuclear Information System (INIS)

    Novikov, I.I.; Roschupkin, V.V.

    1985-01-01

    The paper reviews the work carried out on the thermodynamic properties of alkali metal vapours. The most systematic investigations concern the sound velocity measurements for saturated and superheated vapours of caesium, for saturated vapour of rubidium, and for superheated vapour of potassium. The Joule-Thompson coefficient has been studied in caesium vapour, and the isobaric heat capacity of potassium vapour has also been examined. The experimental methods for all these experiments are described, and the data obtained are presented in tabular form. (U.K.)

  6. Radioactivity in freshwater systems in Cumbria (UK) following the Chernobyl accident

    International Nuclear Information System (INIS)

    Camplin, W.C.; Leonard, D.R.P.; Tipple, J.R.; Duckett, L.

    1989-01-01

    Sampling of fish, water, sediments and plants was carried out in freshwater systems in Cumbria (UK) to study the effects of Chernobyl fallout. Radionuclide concentrations were determined by gamma spectrometry and potassium and calcium ion concentrations in water were measured using atomic absorption spectrometry. The results contained in this report cover the period May 1986-March 1988. Caesium-134 and -137 were readily detected in all materials but ruthenium-103 and -106 were also found in a few samples. Trends in caesium concentrations in fish are difficult to establish because of the wide variation between fish of the same species. (author)

  7. Searching for an oscillating massive scalar field as a dark matter candidate using atomic hyperfine frequency comparisons

    OpenAIRE

    Hees, A.; Guéna, J.; Abgrall, M.; Bize, S.; Wolf, P.

    2016-01-01

    We use six years of accurate hyperfine frequency comparison data of the dual rubidium and caesium cold atom fountain FO2 at LNE-SYRTE to search for a massive scalar dark matter candidate. Such a scalar field can induce harmonic variations of the fine structure constant, of the mass of fermions and of the quantum chromodynamic mass scale, which will directly impact the rubidium/caesium hyperfine transition frequency ratio. We find no signal consistent with a scalar dark matter candidate but pr...

  8. Radioactivity monitoring of the Irish marine environment 1988 - 1990

    International Nuclear Information System (INIS)

    O'Grady, John; Currivan, Lorainne; McEnri, Catherine; O'Colmain, Mairin; Colgan, P.A.; Cunningham, J.D.

    1991-07-01

    This report presents estimates of the radiaiton doses to the Irish public arising from caesium-137 and caesium-134, the contaminating radionuclides of greatest radiological significance. The doses are expressed in terms of individual and collective doses and are assessed against the system of dose limitation recommended by the International Commission on Radiological Protection (ICRP) which is embodied in the Basic Safety Standards Directive of the European Community. The doses are also compared with doses arising from background radiation and the associated risks are considered in the context of some of the common risks in everyday life

  9. The distribution and dynamics of radionuclides in the terrestrial environment

    International Nuclear Information System (INIS)

    Horrill, A.D.; Howson, G.

    1988-10-01

    Caesium-137, plutonium-238 and plutonium-239/240 have been determined in soils and vegetation from West Cumbria. Determinations have been made with reference to the land use which is dominated by grassland management. It can be shown statistically that with respect to caesium-137 land use can affect all soil and vegetation inventory. Indications are that a similar situation holds for the plutonium isotopes. A small data bank of information has been gathered on the land management and farming practices of the study area. (author)

  10. Synthesis of available information in Japan about the contamination of food products by radionuclides remaining in the environment after the Fukushima accident

    International Nuclear Information System (INIS)

    2012-01-01

    This report first proposes an overview of the general status of contamination of the land environment in Japan after the Fukushima accident (maps indicate level of Caesium 134 and 137). It outlines and comments that these radioactive caesium deposits are generally the reason of a persistent contamination of some food products. It describes the measures and arrangements implemented in Japan to control the contamination of food products and to restrict their marketing, comments the assessment of the contamination of food products according to results published in Japan since the accident for the different types of food products: agriculture, fishing, meat and milk, mushrooms, other land vegetal products

  11. Order of 12 August 1986 on treatment by ionizing radiation of material and objects in contact with foods and beverages

    International Nuclear Information System (INIS)

    1986-01-01

    This Order applies to packaging material and articles in contact with foods and beverages, when they are treated by cobalt 60 or caesium 137 gamma rays, accelerated electrons of the energy lower than or equal to 10 MeV and X rays of the energy lower than or equal to 10 MeV. (NEA) [fr

  12. Nursering assistance to the radiological accident patients in Goias-Brazil

    International Nuclear Information System (INIS)

    Graciotti, M.E.

    1989-01-01

    A report of a personal experience, during two months of nursering care to the radiological accident victims, due to the disruption of a caesium-137 source, is presented. The biological radiation effects, the radiation hazards due to the doses received and the Kind of exposure, are studied. (M.A.C.) [pt

  13. Nursering assistance to the radiological accident patients in Goiania-an experience report

    International Nuclear Information System (INIS)

    Graciotti, M.E.

    1989-06-01

    In september, 1987, a caesium-137 source was disrupted and caused a serious radiological acident. The victims were hospitalized in the General Hospital in city of Goiania, Goias state, Brazil. This is a report of a personal experience, during the two months of nursering care. (author) [pt

  14. The amount of 137Cs in chosen parts of food chains from localities in the East of Slovakia

    International Nuclear Information System (INIS)

    Cipakova, A.

    2005-01-01

    The aim of this study was to compare the amount of radiocaesium in chosen parts of food chains from localities in the Eastern Slovakia. Prevailing part of radiocaesium is in the upper layer of soils and specific activity of 137 Cs in the first layer for locality Stara Voda in 2000 achieved 152.4 Bq/kg 1 . On the base of results from modified Tessier sequential extraction method we determined that more than 50 % of this radionuclide is in the soil in not extractable fraction. From studied species of mushrooms the highest value was determined in sample of Rozites caperata the and specific activity achieved 1822.0 Bq/kg 1 d. w. The aim of our study was to determine the amount of caesium in chosen parts of food chains from localities in Eastern Slovakia for period 2000-2004. On the base of obtained results we can conclude that radiocaesium migrates vertically in soils very slowly and prevailing part of caesium is in the upper layer. Prevailing part of radiocaesium is in the not extractable fraction. Extremely low concentration of caesium in soil solution is the factor limiting caesium uptake by the root systems, too. Mushrooms are characterised by high ability to accumulate radiocaesium. (authors)

  15. Run-off from roofs

    International Nuclear Information System (INIS)

    Roed, J.

    1985-01-01

    In order to find the run-off from roof material a roof has been constructed with two different slopes (30 deg C and 45 deg C). Beryllium-7 and caesium-137 has been used as tracers. Considering new roof material the pollution removed by runoff processes has been shown to be very different for various roof materials. The pollution is much more easily removed from silicon-treated material than from porous red-tile roof material. Caesium is removed more easily than beryllium. The content of caesium in old roof materials is greater in red-tile than in other less-porous materials. However, the measured removal from new material does not correspond to the amount accumulated in the old. This could be explained by weathering and by saturation effects. This last effect is probably the more important. The measurements on old material indicates a removal of 44-86% of the caesium pollution by run-off, whereas the measurement on new showed a removal of only 31-50%. It has been demonstrated that the pollution concentration in the run-off water could be very different from that in rainwater. The work was part of the EEC Radiation Protection Programme and done under a subcontract with Association Euratom-C.E.A. No. SC-014-BIO-F-423-DK(SD) under contract No. BIO-F-423-81-F. (author)

  16. Studies on the role of molybdenum on iodine transport in the RCS in nuclear severe accident conditions

    International Nuclear Information System (INIS)

    Grégoire, A.-C.; Kalilainen, J.; Cousin, F.; Mutelle, H.; Cantrel, L.; Auvinen, A.; Haste, T.; Sobanska, S.

    2015-01-01

    Highlights: • In oxidising conditions, Mo reacts with Cs and thus promotes gaseous iodine release. • In reducing conditions, CsI remains the dominant form for released iodine. • The nature of released iodine is well reproduced by the ASTEC code. - Abstract: The effect of molybdenum on iodine transport in the reactor coolant system (RCS) under PWR severe accident conditions was investigated in the framework of the EU SARNET project. Experiments were conducted at the VTT-Institute and at IRSN and simulations of the experimental results were performed with the ASTEC severe accident simulation code. As molybdenum affects caesium chemistry by formation of molybdates, it may have a significant impact on iodine transport in the RCS. Experimentally it has been shown that the formation of gaseous iodine is promoted in oxidising conditions, as caesium can be completely consumed to form caesium polymolybdates and is thus not available for reacting with gaseous iodine and leading to CsI aerosols. In reducing conditions, CsI remains the dominant form of iodine, as the amount of oxygen is not sufficient to allow formation of quantitative caesium polymolybdates. An I–Mo–Cs model has been developed and it reproduces well the experimental trends on iodine transport

  17. Consequences of severe radioactive releases to Nordic Marine environment

    DEFF Research Database (Denmark)

    Iosjpe, M.; Isaksson, M.; Joensen, H.P.

    - or minor – radioactive releases to Nordic marine environment. As a reference, the release amounts from a 3000 MWth reactor size were used. Based on source term analyses, the chosen release fractions in the study were: iodine 20% (of the total core inventory), caesium 10%, tellurium 10%, strontium 0...

  18. Author Details

    African Journals Online (AJOL)

    Taura, LS. Vol 14 (2009) - Articles The effect of the parameter ecuti on the total energy convergence of bulk crystal using FHI98MD code. Abstract · Vol 20 (2012) - Articles Lattice dynamical calculations for bcc caesium chloride. Abstract · Vol 20, No 1 (2012) - Articles Linearity and Non-linearity of Photorefractive effect in ...

  19. The radiological accident of Goiania and its legislative implications

    International Nuclear Information System (INIS)

    Costa, Ieda Rubens

    2001-01-01

    Starting from a reflective view of the historical relationships existing between mankind and nature, this work seeks to pinpoint the today crises and ecological awareness in order to better understand the sparse use of various forms of assault relating to the environment, emphasising the caesium 137 accident as an object of this research. The destructive crisis of capitalism and its ethics, has the ecological crisis as only one of its aspects, however, the caesium 137 accident in Goiania was never left to be treated without pertaining to that crisis. In this way, tackling the issue of the caesium 137 and its unfolding disclosures became impossible not to mention the dimensions of cultural, philosophy, politics, economics and legal issues of the accident. Therefore, within the scope of this research, the Caesium 137 accident was treated as to avoid a fragmented analysis. It was also been transformed into a interdisciplinary work, as it shows the configuration of many concepts, but not legal matters in itself, because the Law itself, as a science, does not have an object through excellency. (author)

  20. Facility design, installation and operation

    International Nuclear Information System (INIS)

    Fleischmann, A.W.

    1985-01-01

    Problems that may arise when considering the design, construction and use of a facility that could contain up to tens of petabecquerel of either cobalt-60 or caesium-137 are examined. The safe operation of an irradiation facility depends on an appreciation of the in built safety systems, adequate training of personnel and the existence of an emergency system

  1. [Thermodynamic forecasting of reagents composition for soils decontamination].

    Science.gov (United States)

    Nikolaev, V P; Nikolaevskiĭ, V B; Chirkina, I V; Shcheglov, M Iu

    2009-01-01

    Based on thermodynamic studies, the authors conducted laboratory experiments on searching optimal composition of leaching reagents solution for soils decontamination, when contaminated with Cs-137, of activity coefficient for caesium sulfate microquantities in macrocomponents solutions. The method could be used for modelling the radionuclides phase equillibrium and relocations in soils.

  2. The radiological accident of Goiania and its legislative implications; O acidente radiologico de Goiania e suas implicacoes legistativas

    Energy Technology Data Exchange (ETDEWEB)

    Costa, Ieda Rubens

    2001-07-01

    Starting from a reflective view of the historical relationships existing between mankind and nature, this work seeks to pinpoint the today crises and ecological awareness in order to better understand the sparse use of various forms of assault relating to the environment, emphasising the caesium 137 accident as an object of this research. The destructive crisis of capitalism and its ethics, has the ecological crisis as only one of its aspects, however, the caesium 137 accident in Goiania was never left to be treated without pertaining to that crisis. In this way, tackling the issue of the caesium 137 and its unfolding disclosures became impossible not to mention the dimensions of cultural, philosophy, politics, economics and legal issues of the accident. Therefore, within the scope of this research, the Caesium 137 accident was treated as to avoid a fragmented analysis. It was also been transformed into a interdisciplinary work, as it shows the configuration of many concepts, but not legal matters in itself, because the Law itself, as a science, does not have an object through excellency. (author)

  3. Biological effects of ionizing radiations. Radiological accident from Goiania, GO, Brazil; Efeitos biologicos das radiacoes ionizantes. Acidente radiologico de Goiania

    Energy Technology Data Exchange (ETDEWEB)

    Okuno, Emico, E-mail: emico.okuno@if.usp.br [Instituto de Fisica da Universidade de Sao Paulo (IF-USP), SP (Brazil)

    2013-01-15

    This article presents the fundaments of radiation physics, the natural and artificial sources, biological effects, radiation protection. We also examine the sequence of events that resulted in Goiania accident with a source of caesium-137 from abandoned radiotherapy equipment and its terrible consequences. (author)

  4. Biological effects of ionizing radiations. Radiological accident from Goiania, GO, Brazil

    International Nuclear Information System (INIS)

    Okuno, Emico

    2013-01-01

    This article presents the fundaments of radiation physics, the natural and artificial sources, biological effects, radiation protection. We also examine the sequence of events that resulted in Goiania accident with a source of caesium-137 from abandoned radiotherapy equipment and its terrible consequences. (author)

  5. Measured transfer factors in milk and meat after the Chernobyl reactor accident

    International Nuclear Information System (INIS)

    Bonka, H.; Kueppers, J.; Maqua, M.

    1988-01-01

    After the nuclear reactor accident at Chernobyl the radioactivity in the environment in Aachen was measured in detail at the Lehrgebiet Strahlenschutz in der Kerntechnik. The change of the different radionuclides in the eco-system made it possible to obtain radioecological parameters especially for iodine and caesium. The knowledge about the transport of iodine into cow's milk could be very much improved

  6. Radioactivity in Norwegian Waters: Distribution in seawater and sediments, and uptake in marine organisms

    International Nuclear Information System (INIS)

    Heldal, Hilde Elise

    2001-01-01

    Prior to the detonation of the first thermonuclear bomb, small amounts of radioactivity, for example in mineral water, were considered to be health enriching. Negative experiences related to thermonuclear bombs and several nuclear accidents have, however, changed people's attitude towards radioactivity during the past 40-50 years. Today, there is a common concern for regular and potential accidental releases of radioactivity from sources such as Sellafield. Although this is important, incorrect assessments of the effects of these releases (e.g. created by uncritical journalism) have the potential to harm the country's fisheries and economy. Therefore, it is of major importance to document up-to-date levels of radioactive contamination of the marine environment, and be able to place these into the proper perspectives. The main topics of the thesis may be summarised as follows: (1) Distribution of Caesium-137, Plutonium-238, Plutonium-239,240 and Americium-241 in sediments with emphasis on the Spitsbergen-Bear Island area, (2) Uptake of Caesium-137 in phytoplankton representative for the Barents and Norwegian Seas phytoplankton communities (laboratory experiments), (3) Bioaccumulation of Caesium-137 in food webs in the Barents and Norwegian Seas, (4) Geographical variations of Caesium-137 in harbour porpoises (Phocoena phocoena) along the Norwegian coast, (5) Transport times for Technetium-99 from Sellafield to various locations along the Norwegian coast and the Arctic Ocean

  7. Radioactivity in Norwegian Waters: Distribution in seawater and sediments, and uptake in marine organisms

    Energy Technology Data Exchange (ETDEWEB)

    Heldal, Hilde Elise

    2001-07-01

    Prior to the detonation of the first thermonuclear bomb, small amounts of radioactivity, for example in mineral water, were considered to be health enriching. Negative experiences related to thermonuclear bombs and several nuclear accidents have, however, changed people's attitude towards radioactivity during the past 40-50 years. Today, there is a common concern for regular and potential accidental releases of radioactivity from sources such as Sellafield. Although this is important, incorrect assessments of the effects of these releases (e.g. created by uncritical journalism) have the potential to harm the country's fisheries and economy. Therefore, it is of major importance to document up-to-date levels of radioactive contamination of the marine environment, and be able to place these into the proper perspectives. The main topics of the thesis may be summarised as follows: (1) Distribution of Caesium-137, Plutonium-238, Plutonium-239,240 and Americium-241 in sediments with emphasis on the Spitsbergen-Bear Island area, (2) Uptake of Caesium-137 in phytoplankton representative for the Barents and Norwegian Seas phytoplankton communities (laboratory experiments), (3) Bioaccumulation of Caesium-137 in food webs in the Barents and Norwegian Seas, (4) Geographical variations of Caesium-137 in harbour porpoises (Phocoena phocoena) along the Norwegian coast, (5) Transport times for Technetium-99 from Sellafield to various locations along the Norwegian coast and the Arctic Ocean.

  8. Radionuclides distribution in internal organs of wild animals in alienation zone of Chernobyl NPP

    International Nuclear Information System (INIS)

    Gorbatova, T.A.; Kudryashov, V.P.; Mironov, V.P.

    2002-01-01

    Activities of caesium 137, strontium 90, plutonium isotopes and americium 241 are experimentally defined in the internal organs of bearer and wolf alienation zone of Chernobyl NPP. Radionuclides distribution in the internal organs of wild animals is defined by destruction of nuclear fuel particles

  9. Radioactivity levels in mushrooms collected in the area of Karlsruhe during 1987 and 1988

    International Nuclear Information System (INIS)

    Rueckert, G.; Diehl, J.F.; Heilgeist, M.

    1990-01-01

    Radioactive contamination of wild-growing mushrooms collected in the Northern Black Forest and neighbouring Rhine Valley area has been monitored since the Chernobyl reactor accident. Cs-134, Cs-137, Ag-110m and the natural nuclide K-40 were determined by gamma-spectrometry. Pooled data from all species and all locations showed a decrease in the radio-caesium levels from 1986 to 1988, both in mean values and maximum values. Samples of the same species collected at the same location exhibited large differences, although mixed samples rather than individual mushrooms were measured. Accumulation of caesium was observed particularly in Laccaria amethystina, Xerocomus badius, Xerocomus chrysenteron, Cantharellus tubaeformis, Laccaria laccata, and Russula ochroleuca, with maximum values of 3600 (1986), 2000 (1987), and 1200 (1988) Bq/kg of radio-caesium. A large number of species, among them Calocybe gambosa and Coprinus comatus, showed very small accumulations or no caesium. An accumulation of silver was found in Macrolepiota rhacodes and Agaricus arvensis, which contained a maximum of 11 Bq/kg Ag-110m. (orig.) [de

  10. Radioactivity in Norwegian Waters: Distribution in seawater and sediments, and uptake in marine organisms

    Energy Technology Data Exchange (ETDEWEB)

    Heldal, Hilde Elise

    2001-07-01

    Prior to the detonation of the first thermonuclear bomb, small amounts of radioactivity, for example in mineral water, were considered to be health enriching. Negative experiences related to thermonuclear bombs and several nuclear accidents have, however, changed people's attitude towards radioactivity during the past 40-50 years. Today, there is a common concern for regular and potential accidental releases of radioactivity from sources such as Sellafield. Although this is important, incorrect assessments of the effects of these releases (e.g. created by uncritical journalism) have the potential to harm the country's fisheries and economy. Therefore, it is of major importance to document up-to-date levels of radioactive contamination of the marine environment, and be able to place these into the proper perspectives. The main topics of the thesis may be summarised as follows: (1) Distribution of Caesium-137, Plutonium-238, Plutonium-239,240 and Americium-241 in sediments with emphasis on the Spitsbergen-Bear Island area, (2) Uptake of Caesium-137 in phytoplankton representative for the Barents and Norwegian Seas phytoplankton communities (laboratory experiments), (3) Bioaccumulation of Caesium-137 in food webs in the Barents and Norwegian Seas, (4) Geographical variations of Caesium-137 in harbour porpoises (Phocoena phocoena) along the Norwegian coast, (5) Transport times for Technetium-99 from Sellafield to various locations along the Norwegian coast and the Arctic Ocean.

  11. Additional effective dose equivalent for adults and children in Poland as the result of mushroom consumption

    International Nuclear Information System (INIS)

    Jasinska, H.; Kozak, K.; Mietelski, J.W.

    2004-01-01

    Experimental data of caesium radioactivity in samples of various mushrooms collected all over Poland from 1986 to 1989 are presented. Nearly 80 samples from Poland and a few samples from Austria and USSR were analysed. The effective dose equivalents for adults and children caused by the consumption of one mass unit of dried mushrooms for each sample were estimated. (author)

  12. Alkali metals in fungi of forest soil

    International Nuclear Information System (INIS)

    Vinichuk, M.; Taylor, A.; Rosen, K.; Nikolova, I.; Johanson, K.J.

    2009-01-01

    The high affinity of forest soil fungi for alkali metals such as potassium, rubidium, caesium as well as radiocaesium is shown and discussed. Good positive correlation was found between K: Rb concentration ratios in soil and in fungi, when correlation between K: Cs concentration ratios was less pronounced. (LN)

  13. Concentration of 137Cs and 40K in meat of omnivore and herbivore game species in mountain forest ecosystems of Gorski Kotar, Croatia

    International Nuclear Information System (INIS)

    Nikica Sprem; Ivan Babic; Domagoj Barisic; Delko Barisic

    2013-01-01

    The aim of this study was to investigate 137 Cs and 40 K load in large mammal game species in the mountain forest region of Gorski Kotar in Croatia approximately a quarter of century after the Chernobyl accident. 137 Cs and 40 K activity were determined by the gamma-spectrometric method in 49 meat samples of five large game species: brown bear (Ursus arctos), wild boar (Sus scrofa), roe deer (Capreolus capreolus), red deer (Cervus elaphus), and chamois (Rupicapra rupicapra). The results indicated that herbivore game species (roe deer, red deer and chamois) show significantly lower 137 Cs concentrations than omnivore species (brown bear, wild boar), thereby confirming the hypothesis that different dietary strategy impact caesium concentrations in meat. The measured caesium load in brown bear meat was in the range of two orders of magnitude, while caesium load in wild boar meat was found in the range of one order of magnitude. The estimated effective equivalent dose showed that uptake of the highest caesium doses would be from consumption of omnivore species meat, while much lower doses could be taken in with the consumption of meat from herbivore species. (author)

  14. Sorption of radionuclides on geological samples from the Bradwell, Elstow, Fulbeck and Killingholme site investigations

    International Nuclear Information System (INIS)

    Berry, J.A.; Coates, H.A.; Green, A.; Littleboy, A.K.

    1988-06-01

    The sorption of chloride, caesium, calcium, nickel and americium on geological samples collected during the site investigations at Bradwell, Elstow, Fulbeck and Killingholme has been studied. Through-diffusion and batch sorption techniques were used and experiments were designed to give a direct comparison between the sorptive behaviour of material from each site. (author)

  15. Solidification of highly active wastes

    International Nuclear Information System (INIS)

    Morris, J.B.

    1984-11-01

    Final reports are presented on work on the following topics: glass technology; enhancement of off-gas aerosol collection; formation and trapping of volatile ruthenium; volatilisation of caesium, technetium and tellurium in high-level waste vitrification; deposition of ruthenium; and calcination of high-level waste liquors. (author)

  16. Bulletin of Materials Science | Indian Academy of Sciences

    Indian Academy of Sciences (India)

    All-inorganic caesium lead-halide perovskite CsPbBr 3 and CsPb 2 Br 5 powders have emerged as attractive optoelectronic materials owing to their stabilities and highly efficient photoluminescence (PL). Herein we report a facile chemical route to prepare highly luminescent monoclinic CsPbBr 3 and tetragonal CsPb 2 Br 5 ...

  17. Environmental radioactivity in Greenland in 1976

    International Nuclear Information System (INIS)

    Aarkrog, A.; Lippert, J.

    1977-07-01

    Measurements of fall-out radioactivity in Greenland in 1976 are reported. Strontium-90 (and Caesium-137 in most cases) was determined in samples of precipitation, sea water, vegetation, animals, and drinking water. Estimates are given of the mean contents of 90 Sr and 137 Cs in the human diet in Greenland in 1976. (author)

  18. Order of 21 June 1984 on trade in garlic, onions and shallots treated by ionizing radiation

    International Nuclear Information System (INIS)

    1984-01-01

    This Order sets the licensing conditions for possession with a view to the sale and putting on sale of onion, garlic and shallot bulbs whose germination has been inhibited by exposure to cobalt 60 or caesium 137 gamma radiation or to accelerated electron beams with an energy below or equal to 10 million electron-volts. (NEA) [fr

  19. Order of 29 December 1988 on treatment of strawberries by ionizing radiation

    International Nuclear Information System (INIS)

    1989-01-01

    This order specifies the conditions for authorizing with a view to selling or putting on sale strawberries whose preservation has been obtained through exposure to cobalt 60 or caesium 137 radiation or to electron beams with an energy below or equal to 10 million electron-volts (10 MeV). (NEA) [fr

  20. Synthesis of enantiomerically pure (R)- and (S)-2-sulfanylpropanoic acids (‘thiolactic acid’) from ethyl (S)-lactate using pig liver esterase

    NARCIS (Netherlands)

    Hof, Robert P.; Kellogg, Richard M.

    1995-01-01

    The methanesulfonates of optically pure ethyl (S)-lactate or ethyl (R)-2-chloropropanoate 5, obtained with inversion of configuration from ethyl (S)-lactate on treatment with SOCl2, can be substituted by caesium thiolates with inversion of configuration to yield (R) and (S) ethyl

  1. SYNTHESIS OF ENANTIOMERICALLY PURE (R)-2-SULFANYLPROPANOIC AND (S)-2-SULFANYLPROPANOIC ACIDS (THIOLACTIC ACID) FROM ETHYL (S)-LACTATE USING PIG-LIVER ESTERASE

    NARCIS (Netherlands)

    HOF, RP; KELLOGG, RM

    1995-01-01

    The methanesulfonates of optically pure ethyl (S)-lactate or ethyl (R)-2-chloropropanoate 5, obtained with inversion of configuration from ethyl (S)-lactate on treatment with SOCl2, can be substituted by caesium thiolates with inversion of configuration to yield (R) and (S) ethyl

  2. A functional mimic of natural peroxidases : synthesis and catalytic activity of a non-heme iron peptide hydroperoxide complex

    NARCIS (Netherlands)

    Choma, CT; Schudde, EP; Kellogg, RM; Robillard, GT; Feringa, BL

    1998-01-01

    Site-selective attachment of unprotected peptides to a non-heme iron complex is achieved by displacing two halides on the catalyst by peptide caesium thiolates, This coupling approach should be compatible with any peptide sequence provided there is only a single reduced cysteine. The oxidation

  3. Alkali metal and ammonium chlorides in water and heavy water (binary systems)

    CERN Document Server

    Cohen-Adad, R

    1991-01-01

    This volume surveys the data available in the literature for solid-fluid solubility equilibria plus selected solid-liquid-vapour equilibria, for binary systems containing alkali and ammonium chlorides in water or heavy water. Solubilities covered are lithium chloride, sodium chloride, potassium chloride, rubidium chloride, caesium chloride and ammonium chloride in water and heavy water.

  4. Order of 17 May 1985 on treatment by ionizing radiation of gum-arabic, dehydrated vegetables and cereal flakes and seeds

    International Nuclear Information System (INIS)

    1985-01-01

    This Order fixes the licensing conditions for the sale of gum-arabic, dehydrated vegetables and cereal flakes and seeds for use in dairy products, whose microbial decontamination was obtained through exposure to cobalt 60 or caesium 137 gamma-rays or electron beams with an energy below or equal to 10 MeV. (NEA) [fr

  5. Improved detectability of barbiturates in high-performance liquid chromatography by pre-column labelling and ultraviolet detection

    NARCIS (Netherlands)

    Hulshoff, A.; Roseboom, H.; Renema, J.

    1979-01-01

    2-Naphthacyl derivatives of barbiturates are formed in acetone at 30° within 30 min, in an essentially quantitative manner, using caesium carbonate as a catalyst. These derivatives absorb UV radiation strongly at 254 nm. Using a variable-wavelength detector set at 249 nm, 1 ng of

  6. Environmental radioactivity in Greenland in 1974

    International Nuclear Information System (INIS)

    Aarkrog, A.; Lippert, J.

    1975-07-01

    Measurements of fall-out radioactivity in Greenland in 1974 are reported. Strontium 90 (and Caesium-137 in most cases) was determined in samples of precipitation, sea water, vegetation, animals, and drinking water. Estimates are given of the mean contents of 90 Sr and 137 Cs in the human diet in Greenland in 1974. Three Greenlanders were measured by wholebody counting. (author)

  7. Environmental radioactivity in Greenland in 1975

    International Nuclear Information System (INIS)

    Aarkrog, A.; Lippert, J.

    1976-07-01

    Measuremtns of fall-out radioactivity in Greenland in 1975 are reported. Strontium-90 (and Caesium-137 in most cases) was determined in samples of precipitation, sea water, vegetation, animals, and drinking water. Estimates are given of the mean contents of 90 Sr and 137 Cs in the human diet in Greenland in 1975. (author)

  8. Psycho-social impact of the cesium-137 accident in the Brazilian society

    International Nuclear Information System (INIS)

    Chaves, E.G.

    1993-01-01

    The author intends to question the assumed current public opinion that the psycho-social impact, resulting from the Goiania accident, is related with the ignorance of those who handled the caesium-137 source capsule, as well as the way media explained the accident. Some important aspects related to social behaviour during and after the accident are also shown. (B.C.A.)

  9. Order of 6 Jan 1988 on the treatment by ionizing radiation of dried fruits and vegetables

    International Nuclear Information System (INIS)

    1988-01-01

    This Order specifies the conditions required for authorizing possession with a view to sale or putting on sale dried vegetables and dried fruit which have been irradiated for purposes of insect control through exposure to cobalt 60 or caesium 137 gamma radiation or to electron beams with an energy below or equal to 10 million electron-volts [fr

  10. Chemical data for the calculation of fission product releases in design basis faults in PWRs

    International Nuclear Information System (INIS)

    Ali, S.M.; Bawden, R.J.; Garbett, K.; Deane, A.M.; Large, N.R.

    1982-04-01

    This review considers the chemistry of caesium and iodine and their volatility under the conditions which would exist during a number of design-basis faults. It recommends values which should be used for the distribution of these elements between liquid and gas phases. (author)

  11. The Roll of Canopy on Interception and Redistribution of Anthropogenic Radionuclides Derived from Fukushima Daiichi Nuclear Power Plant Accident in Coniferous Forest Plantations

    Science.gov (United States)

    Kato, H.; Onda, Y.; Kawaguchi, S.; Gomi, T.

    2011-12-01

    Soil, vegetation and other ecological compartments are expected to be highly contaminated by the deposited radionuclides after the Fukushima Daiichi nuclear power plant (NPP) accident triggered by a magnitude 9.1 earthquake and the resulting tsunami on Marchi 11, 2011. A large proportion of radionuclides which deposited on forest area are trapped by canopies, throughfall and stemflow are the most important pathways for the input of radionuclides into the soil of forest floor. In this study, to investigate the roll of forest canopy on interception and redistribution of the deposited radionuclides, a series of field monitoring experiment of throughfall and stemflow were conducted in coniferous forest plantations in Tochigi prefecture, 170 km southwest from the NPP. A set of 20 throughfall collectors with latticelike distribution and 5 stemflow collectors were located in the 10m × 10m interception plot, and the activities of caesium (137Cs, 134Cs) and radioiodine (131I) in throughfall and stemflow were quantified by using a high purity n-type germanium coaxial gamma ray detectors. Rainfall, throughfall, and stemflow samples were collected from 10 rainfall events, which includes first rainfall event after the NPP accident. The cumulative fallout of radionuclides in the study site was 3400 Bq m-2 for 137Cs, 3300 Bq m-2 for 134Cs, and 26000 Bq m-2 for 131I, respectively. The 137Cs in rainfall decreased exponentially with time since the NPP accident. For the rainfall event of 28 March, which is first rainfall event after the NPP accident, both the amount and concentration of caesium clearly increased with throughfall, whereas the concentration of radioiodine decreased with throughfall. For the subsequent rainfall events, the concentration of caesium decreased with throughfall, whereas radioiodine was not detected as a result of decay due to short half-life. At the end of May, approximately 30% and 60% of total caesium deposited after the NPP accident remained on the

  12. Cesium-137 global fallout into the Ob river basin and its influence on the Kara sea contamination - Weapons fallout cesium-137 in the Ob' catchment landscapes and its influence on radioactive contamination of the Kara sea: Western Siberia, Russia

    Energy Technology Data Exchange (ETDEWEB)

    Semenkov, Ivan N.; Miroshnikov, Alexey Yu. [The Organization of Russian Academy of Sciences Institute of geology of ore deposits, petrography, mineralogy and geochemistry Russian Academy of Sciences (Russian Federation)

    2014-07-01

    There are several high level {sup 137}Cs anomaly zones detected in the deposits of the SW part of the Kara Sea. These anomaly zones were formed in the Ob' and the Enisey river estuaries due to the geochemical 'river-sea' boarder barrier. Level of radiocaesium specific activity reaches 120 Bq*kg{sup -1} in the deposits from these zones. Radiochemical enterprises occur in the both river basins. Their activity results in caesium-137 transfer into the river net. Vast area is contaminated by {sup 137}Cs after nuclear weapons in Semipalatinsk test-site and Kyshtym disaster in the Ob' river basin. Moreover, caesium comes to the Ob' and the Enisey river basins with global atmospheric fallout. The inflow of global fallout caesium-137 to the catchments is 660 kCi (320 kCi including radioactive decay) that is 4 times higher than {sup 137}Cs emission due to Fukushima disaster. Therefore, these river basins as any other huge catchment are an important sources of radioactive contamination of the Arctic Ocean. The aim of our research is to study behavior of global fallout caesium-137 in the landscapes of the Ob and the Enisey river basins. We studied caesium-137 behavior on the example of first order catchments in taiga, wetland, forest-steppe, steppe, and semi-arid landscapes. Geographic information system (GIS) was made. The tenth-order catchments (n=154, Horton coding system) shape 20-groups due to topsoil properties controlling cesium mobility. Eleven first-order basins, characterized 7 groups of tenth order catchments, were studied. And 700 bulk-core soil samples were collected in 2011-2013. Cesium runoff is calculated for 3 first-order river basins in taiga and forest-steppe landscapes. Storage of global fallout caesium-137 declines from undisturbing taiga first-order river basin (90% of cumulative fallout including radioactive decay)> arable steppe and fores-steppe (70 - 75%)> undisturbing wetland (60%). Caesium-137 transfer is high in arable lands

  13. Influence of alkali and alkaline earth elements on the uptake of radionuclides by Pleurototus eryngii fruit bodies

    Energy Technology Data Exchange (ETDEWEB)

    Guillen, J., E-mail: fguillen@unex.es [LARUEX, Dpt. Applied Physics, Faculty of Veterinary Science, University of Extremadura, Avda. Universidad, s/n, 10071 Caceres (Spain); Baeza, A.; Salas, A. [LARUEX, Dpt. Applied Physics, Faculty of Veterinary Science, University of Extremadura, Avda. Universidad, s/n, 10071 Caceres (Spain)

    2012-04-15

    In the literature, there are many data available on radionuclide contents and their transfer to different species of mushrooms. There are some variables, however, which affect the transfer but are very difficult to observe in collected wild mushrooms. An example is the effect of different concentrations of alkali and alkaline earth elements in the soil. Modification of these concentrations in the soil solution has traditionally been used as a countermeasure to deal with radioactively contaminated areas. In the present work, fruiting bodies of Pleurotus eryngii, a saprophytic mushroom, were grown under controlled laboratory conditions, varying the content of alkali (potassium and caesium) and alkaline earth (calcium and strontium) elements. The transfer of {sup 134}Cs, {sup 85}Sr, and {sup 60}Co (added to the cultures) and of natural {sup 210}Pb was analysed by increasing the content of each stable element considered. A significant, but nonlinear, enhancement of stable caesium and {sup 134}Cs was observed with increasing content of stable caesium in the substrate/mycelium. The transfer of {sup 85}Sr decreased with the addition of each stable cation, whereas the {sup 60}Co and {sup 210}Pb transfers were unaffected. - Highlights: Black-Right-Pointing-Pointer The addition of stable potassium did not affect the uptake of radiocaesium. Black-Right-Pointing-Pointer The addition of stable caesium increased the stable caesium and {sup 134}Cs content in the fruiting bodies of Pleurotus eryngii. Black-Right-Pointing-Pointer The addition of calcium reduced the content of calcium and {sup 85}Sr in the fruiting bodies. Black-Right-Pointing-Pointer These countermeasures did not work properly in the case of {sup 60}Co and {sup 210}Pb, no effect was observed.

  14. Formation of cold molecules through the photo-association of cold atoms of Cesium. Existence of long range forces between between cold excited atoms of Cesium; Formation de molecules froides par photoassociation d'atomes froids de cesium. Mise en evidence de forces a longue portee entre atomes froids excites de cesium

    Energy Technology Data Exchange (ETDEWEB)

    Comparat, D

    1999-09-01

    This thesis deals with the experimental study and the theoretical interpretation of the processes involved in photo-association and the formation of cold caesium molecules. It also presents a study of the dipolar forces between a pair of cold excited caesium atoms. We present here the first photo-association experiment on cold caesium atoms: two cold atoms absorb a photon to form an excited electronically excited molecules in a rotation-vibration level. The first production of cold molecules which was realised experimentally, after the spontaneous deexcitation of the photo-associated molecules, is described, stressing the role of the potential well of the molecular states O{sub g}{sup -}(6s+6p{sub 3/2}) or 1{sub u} (6s+6p{sub 3/2}) of caesium. The detection of the formed caesium molecules is based on a two-photons resonant ionisation that creates Cs{sub 2}{sup +} ions, afterwards selectively detected. Temperatures around 20-200 {mu}K have been measured. The photo-associative spectroscopy is described on the theoretical point of view: a detailed theoretical study allows to calculate precisely the asymptotic parts of the potential curves. On the experimental point of view, we present the spectroscopy of the extern potential well of the caesium state O{sub g}{sup -}(6s+6p{sub 3/2}) and the construction of an effective potential curve of the RKR type. A unified theory of photo-association in weak field, considered as a collision assisted by laser, is developed. The cold atoms experiments allow to study and control the collision between two atoms whose mutual interaction is of the dipole-dipole type. Two different physical systems are studied: a sample of Rydberg atoms, and the photo-association process which is a laser-assisted collision. A modification of the motion of one pair of atoms makes it possible to control the bipolar forces and to choose the atoms relative speeds. (author)

  15. National survey of human body radioactivity measured by a mobile whole-body counter and installed whole-body counters

    International Nuclear Information System (INIS)

    Boddy, K.; Fenwick, J.D.; McKenzie, A.L.

    1989-05-01

    Body radioactivity in the general public has been measured in 2339 volunteers throughout the U.K. A mobile whole-body monitor visited collaborating Medical Physics Departments and data were also contributed by Medical Physics Departments possessing installed counters. Levels of body radiocaesium ranged from below detection level to 4149 Bq. Radiocaesium levels were normalised by dividing by the content of natural body potassium-40. In all cases, the dose rate to the body from radiocaesium was less than that from potassium-40. Radiocaesium levels were 2-3 times higher in N.W. England, Scotland and N. Wales than the rest of the country, but this factor is much less than the variation in deposition of Chernobyl radiocaesium. This discrepancy may be accounted for by the nationwide distribution of foodstuffs. At all sites where volunteers were monitored, the ratio of caesium-137/caesium-134 was consistent with a radiocaesium intake attributable primarily to fallout from the Chernobyl fire. (author)

  16. Fission gas release and swelling in the fuel pins M1-3 and F9-3: Risoe Fission Gas Project

    Energy Technology Data Exchange (ETDEWEB)

    Walker, C T; Ray, I L.F.; Coquerelle, M; Blank, H

    1982-01-01

    This report presents results for the microscopic swelling local swelling and local gas release in the pin sections M1-3-11 and F9-3-44. The local gas release was derived from the concentration of retained xenon which was measured with the electron microprobe. In addition to xenon, the radial distributions of caesium and neodymium were also determined by EMPA. Caesium is assumed to contribute to microscopic swelling because it results mainly from the decay of /sup 133/Xe, /sup 135/Xe and /sup 137/Xe and, therefore, is trapped together with xenon in bubbles and pores. Neodymium, on the other hand, is soluble in UO/sub 2/ and does not migrate under the influence of the temperature gradients that exist during irradiation. Therefore, the radial distribution of this fission product is an indelible imprint of the burn-up from which the average flux depression can be deduced. 1 ref., 15 figs., 3 tabs.

  17. A study of fluid alkali metals in the critical region

    International Nuclear Information System (INIS)

    Balasubramanian, R.

    2006-01-01

    On the basis of the generalised van der Waals equation of state, Riedel's thermodynamic similarity parameter, a measure of the temperature dependence of vapour pressure in the critical region is determined for caesium, rubidium and potassium. This generalised equation differs from the known van der Waals equation of state by the modified expression for molecular pressure. The results of determination of Riedel's thermodynamic similarity parameter of caesium, rubidium and potassium are in good agreement with experimental data. Moreover, the given generalised van der Waals equation of state yields a better fit with experimental data on Riedel's thermodynamic similarity parameter for fluid alkali metals when compared with other correlations such as Van Ness and Abbott equation, Pitzer expansion, Pitzer acentric factor correlation, modified Rackett technique, Lee-Kesler vapour pressure relation and Clausius-Clayperon equation

  18. Contributions by emissions from nuclear installations to concentrations of radionuclides in milk

    CERN Document Server

    Green, N

    1983-01-01

    A year-long study has been carried out to determine whether milk produced near nuclear sites contains concentrations of radionuclides that can be attributed to discharges from the installations, and, as a consequence, whether there is enhanced exposure of those members of the public who consume this milk. Eight creameries were chosen and monthly samples of milk were taken for analysis. The concentrations of caesium-137 and strontium-90 were measured and compared with results from a national survey conducted as part of the Board's environmental radioactivity surveillance programme. No effect attributable to discharges from the nuclear establishments was identified. The activity concentrations ranged between 0.1 and 3 times the national average; the variation relates mainly to rainfall in the area, although other factors may also have an effect. However, milk contributes only a small fraction of the total dietary intake of caesium-137 and strontium-90, and so the exposure of persons consuming the milk varies on...

  19. Validation of Cs-137 measurement in food samples using gamma spectrometry system

    International Nuclear Information System (INIS)

    Yii Mei Wo; Kamarozaman Ishak

    2005-01-01

    Cs-137 was found to be one of major radionuclide contaminant present in foods consumed by human. In some countries, regulations required consumption foods moving in international trade to be scanned for caesium (Cs-134 and Cs-137) to ensure it does not exceeding the maximum permissible level. This is to ensure that the intake of such foods will not accumulate radionuclide until the significant level inside the human body. Gamma Spectrometry System was used to perform the measurement of caesium isotopes, because it was one of the easiest methods to be performed. This measuring method must be validated for several parameters include specificity, precision (repeatability), bias (accuracy), linearity, range, detection limit, robustness and ruggedness in order to ensure it is fit for the purpose. This paper would summarise how these parameters were fulfilled for this analytical method using several types certified reference materials. The same validated method would be considered workable on Cs-134 as well. (Author)

  20. Chemical aspects of fission product transport in the primary circuit of a light water reactor

    International Nuclear Information System (INIS)

    Bowsher, B.R.; Dickinson, S.; Nichols, A.L.; Ogden, J.S.; Potter, P.E.

    1985-01-01

    The transport and fission products in the primary circuit of a light water reactor are of fundamental importance in assessing the consequences of severe accidents. Recent experimental studies have concentrated upon the behaviour of simulant fission product species such as caesium iodide, caesium hydroxide and tellurium, in terms of their vapour deposition characteristics onto metals representative of primary circuit materials. An induction furnace has been used to generate high-density/structural materials aerosols for subsequent analysis, and similar equipment has been incorporated into a glove-box to study lightly-irradiated UO/sub 2/ clad in Zircaloy. Analytical techniques are being developed to assist in the identification of fission product chemical species released from the fuel at temperatures from 1000 to 2500 0 C. Matrix isolation-infrared spectroscopy has been used to identify species in the vapour phase, and specific data using this technique are reported

  1. Negative hydrogen ion production mechanisms

    Energy Technology Data Exchange (ETDEWEB)

    Bacal, M. [UPMC, LPP, Ecole Polytechnique, UMR CNRS 7648, Palaiseau (France); Wada, M. [School of Science and Engineering, Doshisha University, Kyoto 610-0321 (Japan)

    2015-06-15

    Negative hydrogen/deuterium ions can be formed by processes occurring in the plasma volume and on surfaces facing the plasma. The principal mechanisms leading to the formation of these negative ions are dissociative electron attachment to ro-vibrationally excited hydrogen/deuterium molecules when the reaction takes place in the plasma volume, and the direct electron transfer from the low work function metal surface to the hydrogen/deuterium atoms when formation occurs on the surface. The existing theoretical models and reported experimental results on these two mechanisms are summarized. Performance of the negative hydrogen/deuterium ion sources that emerged from studies of these mechanisms is reviewed. Contemporary negative ion sources do not have negative ion production electrodes of original surface type sources but are operated with caesium with their structures nearly identical to volume production type sources. Reasons for enhanced negative ion current due to caesium addition to these sources are discussed.

  2. Report of the radiological protection procedures adapted in the Goiania General Hospital for assistance to the victims of the radiological accident with Cesium 137

    International Nuclear Information System (INIS)

    1989-08-01

    A caesium-137 capsule, illegal removed from a desactivated health center of the Instituto Goiano de Radioterapia, was disrupted causing a serious radiological accident. The dimensions of the accident were worsened due to some facts such as: the caesium-137 was in the chloride from, which is a very soluble compound the accident was notify to the competent authorities only several days after the capsule was removal and during this period of time some people handled the souce directly, without knowing its potential danger. This paper descibes the measures adopted in the Goiania General Hospital to restrict the exposure of workers and members of the public and to minimize the consequences of unavoidable exposures in such a way to assure that the annual dose limits were not exceeded. An efficiency evaluation of the methods adopted for the decontamination of the victims was made and its described in the report. (author) [pt

  3. Burn-Up Determination by High Resolution Gamma Spectrometry: Fission Product Migration Studies

    Energy Technology Data Exchange (ETDEWEB)

    Forsyth, R S; Blackadder, W H; Ronqvist, N

    1967-04-15

    The migration of solid fission products, in particular caesium and ruthenium, in high temperature oxide fuel can create a severe problem during the application of non-destructive burn-up methods employing gamma spectrometry, since caesium-137 is otherwise the most convenient long-lived burn-up monitor and ruthenium-106 can be used to distinguish between fissions in U-235 and Pu-239. As part of an experimental programme to develop burn-up methods, gamma scanning experiments have been performed on slices of irradiated UO{sub 2} pellets using a lithium-drifted germanium detector. The usefulness of the technique for migration studies has been demonstrated by comparing the fission product distribution curves across the specimen diameters with the microstructure of the specimens after polishing and etching.

  4. Research and application of inorganic selective sorbents at Mayak PA; Recherches et applications sur l'utilisation de sorbants specifiques a Mayak

    Energy Technology Data Exchange (ETDEWEB)

    Logunov, M.V.; Skobtsov, A.S.; Soldatov, B.V.; Pazdnikov, A.P.; Voroshilov, Y.A.; Rovny, S.I. [Mayak Production Association, Chelyabinsk Region (Russian Federation)

    2004-12-01

    This work has been performed in order to identify selective inorganic sorbents for caesium and strontium. Thin-layer sorbents with nickel ferrocyanide embedded in an inert matrix were found to be the best for caesium. Sorbents including non-stoichiometric manganese dioxide were selected for strontium. Bench tests have been carried out on the purification of desalted water of SNF storage-pool from {sup 137}Cs, and on the purification of contaminated natural water from {sup 90}Sr. The facility for synthesizing the ferrocyanide sorbent with the registered mark 'Seleks-CFN' has been brought into operation. The sorbent ISM-S seems promising for {sup 90}Sr decontamination. (authors)

  5. Chemistry of radio-frequency source of negative hydrogen ions; Chemia radio-frekvencneho zdroja negativnych ionov vodika

    Energy Technology Data Exchange (ETDEWEB)

    Skoviera, J.; Cernusak, I. [Univerzita Komenskeho, Prirodovedecka fakulta, Katedra fyzikalnej a teoretickej chemie, 84215 Bratislava (Slovakia)

    2013-04-16

    International Thermonuclear Experimental Reactor (ITER) is a prototype of nuclear fusion reactor Tokamak currently build in Cadarache. It will use as one of primary plasma heating components a radiofrequency driven negative ion source of deuterium. The purpose of cesium evaporated in the part of this ion source is to react with free electrons which can incidentally destroy generated hydrogen ions and are co-extracted with the hydrogen beam. Goal of this work is to investigate majority of processes which might have impact on hydrogen anion in either formative or destructive way associated with cesium. Generally the caesium dynamics is very complex in such sources and the interplay of the individual contributions and their control to establish optimum caesium coverage of the plasma grid is still an open issue. (authors)

  6. Sediment-associated transport and redistribution of Chernobyl fallout radionuclides

    International Nuclear Information System (INIS)

    Walling, D.E.; Rowan, J.S.; Bradley, S.B.

    1989-01-01

    Fallout of Chernobyl-derived radionuclides over the United Kingdom evidenced marked spatial variation. Relatively high levels were recorded in central Wales, but they declined rapidly to the east. As a result the headwaters of the River Severn received significant inputs of fallout, whereas only low levels were recorded over the middle and lower reaches. Measurements of the caesium-137 content of suspended sediment transported by the River Severn and of channel and floodplain sediments collected from various locations within the basin have been used to assess the importance of fluvial transport and redistribution of Chernobyl-derived radionuclides. High concentrations of caesium-137 (up to 1450 mBqg -1 ) were recorded in suspended sediment collected from the lower reaches of the river shortly after the Chernobyl incident and substantial accumulations of Chernobyl-derived radionuclides have been detected in floodplain and channel sediments collected from areas which received only low levels of fallout directly. (author)

  7. Searching for an Oscillating Massive Scalar Field as a Dark Matter Candidate Using Atomic Hyperfine Frequency Comparisons.

    Science.gov (United States)

    Hees, A; Guéna, J; Abgrall, M; Bize, S; Wolf, P

    2016-08-05

    We use 6 yrs of accurate hyperfine frequency comparison data of the dual rubidium and caesium cold atom fountain FO2 at LNE-SYRTE to search for a massive scalar dark matter candidate. Such a scalar field can induce harmonic variations of the fine structure constant, of the mass of fermions, and of the quantum chromodynamic mass scale, which will directly impact the rubidium/caesium hyperfine transition frequency ratio. We find no signal consistent with a scalar dark matter candidate but provide improved constraints on the coupling of the putative scalar field to standard matter. Our limits are complementary to previous results that were only sensitive to the fine structure constant and improve them by more than an order of magnitude when only a coupling to electromagnetism is assumed.

  8. A study of fluid alkali metals in the critical region

    Energy Technology Data Exchange (ETDEWEB)

    Balasubramanian, R. [Department of Physics, Kongu Engineering College, Perundurai, Erode 638 052, Tamil Nadu (India)]. E-mail: drrbala@yahoo.com

    2006-05-31

    On the basis of the generalised van der Waals equation of state, Riedel's thermodynamic similarity parameter, a measure of the temperature dependence of vapour pressure in the critical region is determined for caesium, rubidium and potassium. This generalised equation differs from the known van der Waals equation of state by the modified expression for molecular pressure. The results of determination of Riedel's thermodynamic similarity parameter of caesium, rubidium and potassium are in good agreement with experimental data. Moreover, the given generalised van der Waals equation of state yields a better fit with experimental data on Riedel's thermodynamic similarity parameter for fluid alkali metals when compared with other correlations such as Van Ness and Abbott equation, Pitzer expansion, Pitzer acentric factor correlation, modified Rackett technique, Lee-Kesler vapour pressure relation and Clausius-Clayperon equation.

  9. Radioactive contaminants in raw materials and foodstuffs of plant origin

    International Nuclear Information System (INIS)

    Stankovicj, S.; Krainchanicj, M.; Stankovicj, A.

    1990-01-01

    The paper concentrates on the results of activity level of radioactive caesium 134 and 137 in the samples of raw materials (barley, oats, soybean, sunflower, pumpkin seed, hops, shreded sugar beet, maize), animal feedstuffs (alfalfa, alfalfa meal, rape, concentrates fed to chickens, pigs or bpvines, dry turnip shreds) and foodstuff of plant origin (lettuce, spinach, cabbage, carrot, celery, cucumber, tomato, olives, sesame). All samples - produced locally on the major part but also including some imported stuff -have been subjected to continuous gamma spectrometry starting with the Chernobyl accident in 1986 through 1989. The highest activity of caesium was recorded in the samples of animal feedstuffs (alfalfa, alfalfa meal, rape) in the years 1986 and 1987. In time, however, the activity tends to drop considerably. (author) 4 refs.; 3 tabs

  10. Lichens as biomonitors for radiocaesium following the Chernobyl accident

    International Nuclear Information System (INIS)

    Sloof, J.E.; Wolterbeek, B.Th.

    1992-01-01

    Caesium-137 resulting from the Chernobyl accident was monitored in lichens in The Netherlands. Caesium-137 activity in Parmelia sulcata ranged from 550 to 6100 (average 2500) Bq kg -1 dry weight. The similarity between the lichen data (geographical 137 Cs activity gradients and radioactivity values) and data of wet and dry deposition, indicate the validity of lichen monitoring of atmospheric 137 Cs. The ratio between the 137 Cs activity per unit lichen dry weight (kg) of Parmelia sulcata and the 137 Cs activity deposited per unit surface area (m 2 ) was approximately one. Measurements of 137 Cs accumulation in Xanthoria parietina show that the activity concentration could be expressed both on a dry weight and on a contour surface area basis. The determination of the biological half-life of 137 Cs in lichens was shown to be subject to sources of error such as growth and non-atmospheric/indirect 137 Cs influxes. (Author)

  11. Radiocaesium in the seas of northern Europe: 1980-84

    International Nuclear Information System (INIS)

    Camplin, W.C.; Steele, A.K.

    1991-01-01

    A computer data base of measurements of caesium-134 and caesium-137 in sea water has been compiled. The measurements were carried out by the UK Ministry of Agriculture, Fisheries and Food and include data for the Irish Sea, Bristol Channel, English Channel, North Sea, Scottish waters and other parts of the marine environment of northern Europe. This report covers the sampling period 1980-84 and further information will be published as the data base is expanded. It is hoped that the information will be useful to scientists modelling radionuclide dispersion in the area. In order to assist in the development of new models, diskettes of the data in ASCII files are available, on request, from the first author. The data include the locations of sample collection, collection date, depth salinity, concentration of activity and counting errors. Plots of the geographical scope of the data are also provided to assist the user. (author)

  12. Monitoring of the general population with an installed whole body counter at West Cumberland Hospital, Whitehaven

    International Nuclear Information System (INIS)

    Boddy, K.; Francis, R.A.; Fenwick, J.D.; McKenzie, A.L.

    1989-03-01

    Body radioactivity in the general public has been measured in 395 volunteers in the Whitehaven area, using a whole-body monitor at West Cumberland Hospital. Between October 1986 and October 1987, estimates of total body radiocaesium in 240 volunteers ranged from below detection level to 1844 Bq with a mean of 415 Bq. From October 1987 until May 1988, a further 155 volunteers were monitored, and radiation levels ranged from 34 Bq to 685 Bq, with a mean of 257 Bq. In all volunteers, the ratio of body radiocaesium to body potassium, was well below unity. The average ratio of caesium-137 to caesium-134 from October 1987 to May 1988 was 3.28, corresponding to a ratio of 1.99 at the date of Chernobyl accident. This is consistent with a Chernobyl origin as the primary source for the radiocaesium. There were discernible, but not marked, trends of increasing body radiocaesium with milk and meat/fish consumption. (author)

  13. Diffusion under water-saturated conditions in PFA/OPC-based structural concrete

    International Nuclear Information System (INIS)

    Harris, A.W.; Nickerson, A.K.

    1990-05-01

    A substantial proportion of the volume of the UK radioactive waste repository is likely to be composed of materials based on hydraulic cements. This includes the structural components, which are likely to be manufactured from concrete. The mass transport characteristics of dissolved species for a typical structural concrete, based on a mixture of pulverised fuel ash and ordinary Portland cement, have been measured in a water-saturated condition. Both the water permeability and the diffusion parameters (for caesium, strontium and iodide ion and tritiated water diffusion) are low compared to values obtained for other structural concretes. The intrinsic diffusion coefficients for iodide and caesium ions are in the range 2-5x10 -14 m 2 s -1 . There is no evidence of significant sorption of any of the diffusants studied. (author)

  14. Sorption of radionuclides on London clay

    International Nuclear Information System (INIS)

    Berry, J.A.; Bourke, P.J.; Green, A.; Littleboy, A.K.

    1989-02-01

    Techniques for studying the sorption of radionuclides on London clay have been investigated. This work involved the use of through-diffusion, in-diffusion, high-pressure convection and batch methods to study the sorption of iodide, strontium, caesium and americium. Through-diffusion and high-pressure convection methods were found to be most useful for investigating weakly and moderately sorbing nuclides and give realistic values for sorptivity. The batch technique remains the most practical method of obtaining large quantities of data within a relatively short timescale but gives very high sorptivity values. It is however very useful for intercomparisons of nuclides or geological media. The in-diffusion method requires further refinement for use with strongly sorbing nuclides. Good agreement between through-diffusion and high-pressure convection methods was obtained for the sorptivity of strontium, whilst trends observed for caesium by through-diffusion were confirmed by batch measurements. (author)

  15. WWER expert system for fuel failure analysis using the RTOP-CA code

    International Nuclear Information System (INIS)

    Likhanskii, V.; Evdokimov, I.; Sorokin, A.; Khromov, A.; Kanukova, V.; Apollonova, O.; Ugryumov, A.

    2008-01-01

    The computer expert system for fuel failure analysis of WWER during operation is presented. The diagnostics is based on the measurement of specific activity of reference nuclides in reactor primary coolant and application of a computer code for the data interpretation. The data analysis includes an evaluation of tramp uranium mass in reactor core, detection of failures by iodine and caesium spikes, evaluation of burnup of defective fuel. Evaluation of defective fuel burnup was carried out by applying the relation of caesium nuclides activity in spikes and relations of activities of gaseous fission products for steady state operational conditions. The method of burnup evaluation of defective fuel by use of fission gas activity is presented in details. The neural-network analysis is performed for determination of failed fuel rod number and defect size. Results of the expert system application are illustrated for several fuel campaigns on operating WWER NPPs. (authors)

  16. Fine-grained sediment deposition on mussel beds in the Oosterschelde (The Netherlands), determined from echosoundings, radio-isotopes and biodeposition field experiments

    International Nuclear Information System (INIS)

    Brinke, W.B.M. ten; Augustinus, P.G.E.F.

    1995-01-01

    Sedimentation rates of 5-20 cm year -1 were calculated from 137 Cs + 134 Cs activity profiles and echosoundings in a mussel cultivation area in the western part of the Oosterschelde. Sedimentation rates based on 210 Pb activity profiles are far too low, mainly due to the deposition of 'aged' sediment, i.e. sediment eroded elsewhere inside the basin and not fully enriched with 210 Pb at the moment of deposition. Also, specific adsorption to the finest sediment components, mixing, winnowing, and mobilization of the caesium have affected the lead and caesium profiles. Field experiments on mussel plots showed that mussels deposit 5-10 cm of fine-grained sediment during the summer. This biodeposition about equals the settling from flocculation in the water column. Micro-fabric microscope studies revealed that pellets do not dominate the sediments, indicating that some of the pellets are broken down or resuspended. (author)

  17. Experimental comparison of gamma attenuations by glasses, lead, iron and concretes

    International Nuclear Information System (INIS)

    Charamathieu, Andre; Papot, Lucien

    1964-08-01

    The authors report the experimental determination, for lead glasses of density 3.3, 4.2, 5.2 and 6.2, of thicknesses equivalent to thicknesses given for lead, iron, ordinary concrete and barite concrete for Cobalt 60 and Caesium 137 radiations. Results are presented under the form of curves. Attenuation measurements made on this opportunity and those made on various hot cells have been compared with theoretical attenuation curves produced in another CEA document [fr

  18. Theory of diffusion of rare gases in solids

    International Nuclear Information System (INIS)

    Lidiard, A.B.

    1980-01-01

    This paper reviews the basic theoretical description of the solubility and diffusion of rare gas atoms in crystalline solids. It then shows how this description can be used in conjunction with atomistic calculations to understand experimental observations. This understanding is particularly good for ionic compounds and a brief summary of the present situation is given for three main classes, namely those with the rocksalt structure, the fluorite structure and the caesium chloride structure. (author)

  19. Selective decontamination of cesium and strontium from evaporation concentrates of spent fuel reprocessing plants with crown ethers by transport through supported liquid membranes

    International Nuclear Information System (INIS)

    Casas i Garcia, J.

    1993-01-01

    Reprocessing operations lead to the production of radioactive medium activity liquid waste which is treated by evaporation and solutions of very high salinity are thus formed. The concentrates from reprocessing plant evaporators have to be stored in geological storage sites in view of their strong caesium, strontium and actinides activity. These elements, contained in acid and high sodium nitrate content liquid waste, are removed by means of selective extractants, using the supported liquid membrane technique (SLM), which allows them to be stored in surface sites, the actinides and long-life fission products being respectively recycled and concentrated into reduced volumes. The removal of the actinides is done by means of an Octyl N.N Diisobutyl Carbamoyl Methyl Phosphine Oxide (C.M.P.O.) based liquid membrane, whereas the removal of the caesium and strontium involves crown ethers. Supported liquid membranes (S.L.M.s) have the advantage of implementing very small quantities of extractant, but they generally have poor stability. The extractant, the diluent and the phase modifier impregnating the membrane play a vital role in SLM stability; the support also affects stability by its nature and geometry. For the extraction of strontium, the most lipophilic extractant, DtBu 18 C 6, enables higher strontium transfer kinetics to be attained. As regards caesium, the extremely lipophilic nDec B21 C7 is the most efficient. Caesium cannot be quantitatively removed, due to the competition of the very high content of sodium ions in the concentrate. Stable membranes are obtained with DC18 C6 or DtBu18 C6 diluted in alkylbenzenes with an added phase modifier such as decanol or especially isotridecanol

  20. Assessment of the consequences of the Fukushima accident on the environment in Japan, one year after the accident; Bilan des consequences de l'accident de Fukushima sur l'environnement au Japon, un an apres l'accident

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2012-02-28

    Illustrated by several maps and figures, this document proposes and discusses quantitative assessments of radioactive releases in the air (rare gases, iodine, tellurium compounds, caesium), of the atmospheric dispersion of releases, of the contamination of soils by radioactive deposits (dry and humid deposits), of the contamination of food products in Japan (vegetable productions, animal productions like meat, milk, eggs and so on), and of the contamination of the marine environment

  1. Immobilisation of hazardous waste

    International Nuclear Information System (INIS)

    Cope, C.B.

    1983-01-01

    Hazardous waste, e.g. radioactive waste, particularly that containing caesium-137, is immobilised by mixing with cement and solidifiable organic polymeric material. When first mixed, the organic material is preferably liquid and at this time can be polymerisable or already polymerised. The hardening can result from cooling or further polymerisation e.g. cross-linking. The organic material may be wax, or a polyester which may be unsaturated and cross-linkable by reaction with styrene. (author)

  2. Assessment of the consequences of the Fukushima accident on the environment in Japan, one year after the accident

    International Nuclear Information System (INIS)

    2012-01-01

    Illustrated by several maps and figures, this document proposes and discusses quantitative assessments of radioactive releases in the air (rare gases, iodine, tellurium compounds, caesium), of the atmospheric dispersion of releases, of the contamination of soils by radioactive deposits (dry and humid deposits), of the contamination of food products in Japan (vegetable productions, animal productions like meat, milk, eggs and so on), and of the contamination of the marine environment

  3. Measured radioecological parameters after the Chernobyl accident

    International Nuclear Information System (INIS)

    Bonka, H.

    1989-01-01

    After the Chernobyl accident the radioactivity in the environment in Aachen was measured in detail. The change of the different radionuclies in the eco-system made it possible to obtain radioecological parameters especially for iodine and caesium. The most important data obtained like deposition velocity, washout coefficient, retention factor, removal rate constant, and transfer factor food-milk, food-beef, and soil-grass are reported. (orig.)

  4. Specific features of 137Cs migration and accumulation in chernozem soils of forest ecosystems in the zone contaminated due to the Chornobyl accident

    International Nuclear Information System (INIS)

    Tsvetnova, O.B.; Shcheglov, A.I.; Orlov, A.A.

    2005-01-01

    A number of factors influencing 137 Cs fate and biological availability in chernozem soils under the forest vegetation were assessed for various climatic zones. The migration rates of 137 Cs in the profile of chernozem soils were shown to depend primary on forest litter composition and structure. In the absence of forest litter the soil mineralogical composition and humus content become the most influential factors of caesium mobility

  5. Lattice Dynamics of CsBr

    Energy Technology Data Exchange (ETDEWEB)

    Rolandson, S; Raunio, G

    1971-10-15

    The phonon dispersion curves of caesium bromide have been observed by inelastic neutron scattering in the symmetry directions A, S and A and along the symmetry line T. The measurements were performed at 80 and 300 K using a three-axis crystal spectrometer. The observations have been fitted to various versions of the shell model, and the frequency distribution and the temperature dependence of the Debye temperature calculated from the model which gives the best fit to the experimental frequencies

  6. Removal of foliar radiocaesium by sprinkling

    International Nuclear Information System (INIS)

    Anguissola Scotti, I.; Silva, S.; Carini, F.

    1993-01-01

    Tests of contamination of leaves with 134 Cs were carried out on wheat and tomato plants in order to discover whether sprinkler irrigation could remove some of the radioactivity deposited on the shoots. The results show that caesium is absorbed rapidly through the leaves of both wheat and tomato plants and that wheat grain and tomatoes in the sprinkled areas had 80% and 55% lower concentrations of 134 Cs, respectively, compared with those in the non-irrigated areas. (Author)

  7. The velocity of sound

    International Nuclear Information System (INIS)

    Beyer, R.T.

    1985-01-01

    The paper reviews the work carried out on the velocity of sound in liquid alkali metals. The experimental methods to determine the velocity measurements are described. Tables are presented of reported data on the velocity of sound in lithium, sodium, potassium, rubidium and caesium. A formula is given for alkali metals, in which the sound velocity is a function of shear viscosity, atomic mass and atomic volume. (U.K.)

  8. Thermodynamic properties of cesium in the gaseous phase

    International Nuclear Information System (INIS)

    Vargaftik, N.B.; Voljak, L.D.; Stepanov, V.G.

    1985-01-01

    Tables of the thermodynamic properties of caesium in the gaseous phase are presented for a wide range of temperature and pressure. The thermodynamic properties include: enthalpy, entropy, specific heat, specific volume, sound velocity and compressibility factor. The values have been calculated from pressure-volume-temperature measurements by various authors. Experimental apparatus to determine these measurements is described, together with an outline of the method employed to process the results, and the error estimates. (U.K.)

  9. Lattice Dynamics of CsBr

    International Nuclear Information System (INIS)

    Rolandson, S.; Raunio, G.

    1971-10-01

    The phonon dispersion curves of caesium bromide have been observed by inelastic neutron scattering in the symmetry directions A, S and A and along the symmetry line T. The measurements were performed at 80 and 300 K using a three-axis crystal spectrometer. The observations have been fitted to various versions of the shell model, and the frequency distribution and the temperature dependence of the Debye temperature calculated from the model which gives the best fit to the experimental frequencies

  10. Comparison of the measured specific activities of cesium in mushrooms, pine tree twigs, blueberries, honey and game in Aachen after 1986

    International Nuclear Information System (INIS)

    Bonka, H.; Schmelz, G.

    1998-01-01

    After the nuclear reactor accident at Chernobyl the specific activity in mushrooms originating from the region of Aachen was continuously measured until today. At the same time the specific activity was determined in pine tree twigs, blueberries, honey and game. There is a strong connection of the living organisms and the inanimate environment within the forest ecosystem. The decrease of the specific caesium activity in living organisms is slower than in the other environment. (orig.) [de

  11. Remote atomic clock synchronization via satellites and optical fibers

    OpenAIRE

    Piester, D.; Rost, M.; Fujieda, M.; Feldmann, T.; Bauch, A.

    2011-01-01

    In the global network of institutions engaged with the realization of International Atomic Time (TAI), atomic clocks and time scales are compared by means of the Global Positioning System (GPS) and by employing telecommunication satellites for two-way satellite time and frequency transfer (TWSTFT). The frequencies of the state-of-the-art primary caesium fountain clocks can be compared at the level of 10−15 (relative, 1 day averaging) and time scales can be synchronized...

  12. Radiation monitoring of local foodstuffs in some settlements in Belarus located not far from woodlands

    International Nuclear Information System (INIS)

    Devojno, A.N.; Nesterenko, V.B.; Mukhlaev, A.A.; Troyanovskij, S.V.

    2005-01-01

    Here are the results of radiation monitoring performed by the local centres for radiation control in some settlements located in radiation contaminated territories not far from woodlands. It is shown that within the decennial period from 1993 to 2003 the Caesium 137 radiation contamination of mushrooms, game and milk from private household makes significant values and do not have the decreasing tendency. It is recommended to use possible radioprotective measures of the population under above stated circumstances. (authors)

  13. The IRSN publishes an assessment of doses received in Japan by external irradiation due to radioactive deposits caused by the Fukushima-Daiichi power plant accident

    International Nuclear Information System (INIS)

    2011-01-01

    This document first describes how dry and wet radioactive deposits are formed. It also indicates their main components: iodine 131 and 132, caesium 134, 136 and 137, tellurium 132, and barium 140. It describes the different exposure ways due to radioactive deposits in the environment. A map indicates dose level assessments few tens of kilometres around the Fukushima power plant. A brief comment of this map is proposed

  14. Radioactive fallout in air and rain: results to the end of 1976

    International Nuclear Information System (INIS)

    Cambray, R.S.; Fisher, E.M.R.; Eakins, J.D.; Peirson, D.H.

    1977-04-01

    Samples of atmospheric dust and rainwater have been collected from the United Kingdom and elsewhere. Results are presented an analyses of these samples for various fission products and certain other radionuclides. The average concentration of the long-lived fission product caesium-137 in air in the United Kingdom was, in 1976, about one-third of that in 1975 and about 1% of the maximum which was reached in 1963 to 64. The concentration in rain and the deposition of caesium-137 and strontium-90 averaged over the United Kingdom for 1976 were about half those for 1975. No barium-140 or iodine-131, indicative of recent atmospheric tests, was detected in the United Kingdom after the Chinese explosion on 24 January 1976 but measurable concentrations were detected in air at Hong Kong during February. Fresh activity from the Chinese explosion on 26 September 1976 was detected in the United Kingdom. The peak deposition of iodine-131 that occurred in the second week in Octber was greater than at any time since January 1963 although the total deposition of iodine-131 was less than one-tenth of that in 1962 to 63. Trace amounts of fresh activity attributable to the high-yield Chinese explosion of 17 November were detected in the United Kingdom in December 1976. In the southern hemisphere the mean concentration of caesium-137 in air in 1976 was about half that in 1975. An estimate is made of the worldwide deposit of caesium-137 and strontium-90. The gamma and beta-ray dose rates from fallout at Chilton are estimated from the observed deposition. Measurements of short-lived fission products in air and rain are given in an Appendix. (author)

  15. The Harwell fallout monitoring programme and its response to the Chernobyl accident

    International Nuclear Information System (INIS)

    Cambray, R.S.

    1988-01-01

    The Harwell laboratory operates a worldwide network of air and rain sampling stations for radioactivity in the atmosphere. In the months after the Chernobyl accident of 29 April 1986 the network was used to study the distribution and behaviour of radioactive debris from that source. An estimate of 5 x 10 16 Bq of caesium-137 has been deduced for the global distribution from Chernobyl

  16. Selective decontamination for cesium and strontium in evaporation concentrates from reprocessing plants with crown ethers by transport through supported liquid membranes

    International Nuclear Information System (INIS)

    Casas i Garcia, J.

    1991-01-01

    Reprocessing operations lead to the production of radioactive medium activity liquid waste which is treated by evaporation. The concentrates from reprocessing plant evaporators have to be stored in geological storage sites in view of their strong caesium, strontium and actinides activity. These elements, contained in acid and high sodium nitrate content liquid waste, are removed by means of selective extractants, using the supported liquid membrane technique (SLM), which allows them to be stored in surface sites, the actinides and long-life fission products being respectively recycled and concentrated into reduced volumes. The removal of the actinides is done by means of an Octyl N.N Diisobutyl Carbamoyl Methyl Phosphine Oxyde (C.M.P.O.) based liquid membrane, whereas the removal of the caesium and strontium involves crown ethers. Supported liquid membranes (S.L.M.s) have the advantage of implementing very small quantities of extractant, but, they generally have poor stability. The extractant, the diluent and the phase modifier that constitute the organic phase impregnating the membrane play a vital role in SLM stability; the support also affects stability by its nature and geometry. For the extraction of strontium, DtBu 18 C6 enables higher strontium transfer kinetics to be attained than with DC18 C6. As regards caesium, nDec B21 C7 is the most efficient. Unlike strontium, caesium cannot be quantitatively removed, due to the competition of sodium ions in the concentrate. Stable membranes are obtained with DC18 C6 or DtBu18 C6 diluted in alkylbenzene with an added phase modifier such as decanol or isotridecanol. The highest strontium transfer kinetics were obtained with the DC18 C6/hexylbenzene/isotridecanol mixture

  17. Evaluation of the neutral comet assay for detection of alpha-particle induced DNA-double-strand-breaks

    International Nuclear Information System (INIS)

    Hofbauer, Daniela

    2010-01-01

    Aim of this study was to differentiate DNA-double-strand-breaks from DNA-single-strand-breaks on a single cell level, using the comet assay after α- and γ-irradiation. Americium-241 was used as a alpha-irradiation-source, Caesium-137 was used for γ-irradiation. Because of technical problems with both the neutral and alkaline comet assay after irradiation of gastric cancer cells and human lymphocytes, no definite differentiation of DNA-damage was possible.

  18. Preparation of graphite targets for radiocarbon dating by tandem accelerator mass spectrometer (TAMS)

    International Nuclear Information System (INIS)

    Lowe, D.C.

    1984-01-01

    The introduction of TAMS has exciting implications for radiocarbon dating but improved sample preparation methods are needed. This paper describes a promising method for the conversion of a few milligrams of wood or charcoal into graphite targets for use in a caesium sputter ion source. Targets containing a large proportion of G-type graphite produced large C - currents, but those containing a high proportion of turbostatic Tn graphite were unsatisfactory; the type of graphite in the target is clearly of significance. (author)

  19. An assessment of the melting, boiling, and critical point data of the alkali metals

    International Nuclear Information System (INIS)

    Ohse, R.W.; Babelot, J.-F.; Magill, J.

    1985-01-01

    The paper reviews the measured melting, boiling and critical point data of alkali metals. A survey of the static heat generation methods for density and pressure-volume-temperature measurements is given. Measured data on the melting and boiling temperatures of lithium, sodium, potassium, rubidium and caesium are summarised. Also measured critical point data for the same five alkali metals are presented, and discussed. (U.K.)

  20. Respiration of seed lobes after γ-irradiation of seeds with stimulating doses

    International Nuclear Information System (INIS)

    Vagabova, M.Eh.

    1975-01-01

    Air-dry black bean, mustard, castor-oil plant and maize seeds were exposed to caesium-137 gamma rays. Are the radiation doses used during the early stages of development the process of respiration in the cotyledons proved to be stimulated. As the author points out, this increases the energy supply to the developing embryo and contributes to the general mechanisms involved in the radiation stimulation of plant development. (V.A.P.)

  1. Radionuclide getters in the near-field chemistry of repositories

    International Nuclear Information System (INIS)

    Holland, T.R.; Lee, D.J.

    1991-06-01

    The solubility of many radionuclides in a radwaste repository will be limited by the high pH of the cement based system. However, the inclusion of specific sorbing media, within the cement backfill, offers the ability to improve the retention of the more mobile radionuclides, such as caesium and iodine; thereby further reducing their environmental impact. This programme of work is intended to assess the radionuclide sorption efficiency of selected inorganic getters incorporated in cement. (author)

  2. A method to detect soil carbon degradation during soil erosion

    OpenAIRE

    F. Conen; M. Schaub; C. Alewell

    2009-01-01

    Soil erosion has been discussed intensively but controversial both as a significant source or a significant sink of atmospheric carbon possibly explaining the gap in the global carbon budget. One of the major points of discussion has been whether or not carbon is degraded and mineralized to CO2 during detachment, transport and deposition of soil material. By combining the caesium-137 (137Cs) approach (quantification of erosion rates) with stable c...

  3. Using bentonite for NPP liquid waste treatment

    International Nuclear Information System (INIS)

    Bui Dang Hanh

    2015-01-01

    During operation, nuclear power plants (NPPs) release a large quantity of water waste containing radionuclides required treatment for protection of the radiation workers and the environment. This paper introduces processes used to treat water waste from Paks NPP in Hungary and it also presents the results of a study on the use of Vietnamese bentonite to remove radioactive Caesium from a simulated water waste containing Cs. (author)

  4. The IRSN publishes an assessment of doses received in Japan by external irradiation due to radioactive deposits caused by the Fukushima-Daiichi power plant accident; L'IRSN publie une estimation des doses recues au Japon par irradiation externe due aux depots radioactifs provoques par l'accident de la centrale de Fukushima-Daiichi

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2011-07-01

    This document first describes how dry and wet radioactive deposits are formed. It also indicates their main components: iodine 131 and 132, caesium 134, 136 and 137, tellurium 132, and barium 140. It describes the different exposure ways due to radioactive deposits in the environment. A map indicates dose level assessments few tens of kilometres around the Fukushima power plant. A brief comment of this map is proposed

  5. Mineral resource of the month: cesium

    Science.gov (United States)

    Angulo, Marc A.

    2010-01-01

    The article offers information on cesium, a golden alkali metal derived from the Latin word caesium which means bluish gray. It mentions that cesium is the first element discovered with the use of spectroscopy. It adds that the leading producer and supplier of cesium is Canada and there are 50,000 kilograms of cesium consumed of the world in a year. Moreover, it states that only 85% of the cesium formate can be retrieved and recycled.

  6. Geophysical survey at archaeological sites in northeastern Syria

    OpenAIRE

    Mateiciucová, Inna; Milo, Peter; Tencer, Tomáš; Vlach, Marek

    2011-01-01

    From August 25 to September 4, 2008, geophysical surveys were carried out at the Neolithic, Chalcolithic, Bronze and Iron Age tell- and non-tell settlements in the Khabur region in Northeastern Syria (Syrian-Polish-Czech expedition) (Fig. 1). Four sites were prospected: Tell Arbid Abyad, Tell Arbid (West-hill), Khirbet Shane, Khirbet Bezi. The Scintrex Navmag SM-5 – Caesium Magnetometer was used for the measurement of the vertical gradient of the local magnetic field. The measurement resoluti...

  7. A New Animated Infographic on ‘‘137Cs for Assessing and Mitigating Soil Erosion’’

    International Nuclear Information System (INIS)

    Mabit, Lionel; Heng, Lee; Dercon, Gerd; Toloza, Arsenio; Zaman, Mohammad

    2015-01-01

    The SWMCN Subprogramme is proud to present a new animated infographic highlighting the use of fallout radionuclide techniques (i.e. caesium-137 or 137 Cs) to investigate soil erosion and sedimentation processes in agricultural environments. The 137 Cs technique is currently being disseminated by the Joint FAO/IAEA Division in 65 IAEA Member States across all continents. Readers can watch this video at: http://www-naweb.iaea.org/nafa/resources-nafa/soil-Erosion-stream32.mp4

  8. 40K/137Cs discrimination ratios to the aboveground organs of tropical plants

    International Nuclear Information System (INIS)

    Sanches, N.; Anjos, R.M.; Mosquera, B.

    2008-01-01

    In the present work, the accumulation of caesium and potassium in aboveground plant parts was studied in order to improve the understanding on the behaviour of monovalent cations in several compartments of tropical plants. We present the results for activity concentrations of 137 Cs and 40 K, measured by gamma spectrometry, from five tropical plant species: guava (Psidium guajava), mango (Mangifera indica), papaya (Carica papaya), banana (Musa paradisiaca), and manioc (Manihot esculenta). Caesium and potassium have shown a high level of mobility within the plants, exhibiting the highest values of concentration in the growing parts (fruits, leaves, twigs, and barks) of the woody fruit and large herbaceous shrub (such as manioc) species. In contrast, the banana and papaya plants exhibited the lowest levels of 137 Cs and 40 K in their growing parts. However, a significant correlation between activity concentrations of 137 Cs and 40 K was observed in these tropical plants. The 40 K/ 137 Cs discrimination ratios were approximately equal to unity in different compartments of each individual plant, suggesting the possibility of using caesium to predict the behaviour of potassium in several tropical species

  9. {sup 40}K/{sup 137}Cs discrimination ratios to the aboveground organs of tropical plants

    Energy Technology Data Exchange (ETDEWEB)

    Sanches, N. [Instituto de Fisica, Universidade Federal Fluminense, Av. Gal. Milton Tavares de Souza s/n, Gragoata, Niteroi, CEP 24210-346, RJ (Brazil); Anjos, R.M. [Instituto de Fisica, Universidade Federal Fluminense, Av. Gal. Milton Tavares de Souza s/n, Gragoata, Niteroi, CEP 24210-346, RJ (Brazil)], E-mail: meigikos@if.uff.br; Mosquera, B. [Instituto de Fisica, Universidade Federal Fluminense, Av. Gal. Milton Tavares de Souza s/n, Gragoata, Niteroi, CEP 24210-346, RJ (Brazil)

    2008-07-15

    In the present work, the accumulation of caesium and potassium in aboveground plant parts was studied in order to improve the understanding on the behaviour of monovalent cations in several compartments of tropical plants. We present the results for activity concentrations of {sup 137}Cs and {sup 40}K, measured by gamma spectrometry, from five tropical plant species: guava (Psidium guajava), mango (Mangifera indica), papaya (Carica papaya), banana (Musa paradisiaca), and manioc (Manihot esculenta). Caesium and potassium have shown a high level of mobility within the plants, exhibiting the highest values of concentration in the growing parts (fruits, leaves, twigs, and barks) of the woody fruit and large herbaceous shrub (such as manioc) species. In contrast, the banana and papaya plants exhibited the lowest levels of {sup 137}Cs and {sup 40}K in their growing parts. However, a significant correlation between activity concentrations of {sup 137}Cs and {sup 40}K was observed in these tropical plants. The {sup 40}K/{sup 137}Cs discrimination ratios were approximately equal to unity in different compartments of each individual plant, suggesting the possibility of using caesium to predict the behaviour of potassium in several tropical species.

  10. A study of sorption mechanism onto cement hydrates by isotherm measurements

    International Nuclear Information System (INIS)

    Sugiyama, Daisuke; Fujita, Tomonari

    2003-01-01

    In the concept for TRU waste disposal in Japan, cement is a potential waste packaging and backfilling material and is expected to provide chemical containment. In particular, the sorption of radionuclides onto cement material, which controls the aqueous concentrations of elements in the porewater, is a very important parameter when considering the release of radionuclides from the near field of a repository. Many safety assessment calculations currently assume radionuclide retardation as linear sorption equilibrium and describe it with a distribution ratio (R d value). In this study, the sorption mechanism is discussed by measuring the sorption isotherm of caesium, strontium and thorium onto Ordinary Portland Cement (OPC) and Calcium Silicate Hydrate (C-S-H gel), to justify and support this assumption. In addition, the effect of competitive sorption between thorium and uranium and other groundwater ions is studied by examining sorption using a range of sodium chloride concentrations to simulate different groundwater ionic strengths. Based on the experimental results, we have showed that: Caesium and strontium sorb by substitution for Ca in C-S-H phases and the presence of some calcium sites with different ion-exchange log K values is suggested; Thorium would be fixed in a surface co-precipitation to form a solubility-limiting phase. The results of sorption experiments are reasonably well modelled by the ion-exchange model for caesium and strontium and the surface co-precipitation model for thorium, respectively. (author)

  11. The characterisation of vapour-phase alkali metal-tellurium-oxygen species

    International Nuclear Information System (INIS)

    Gomme, R.A.; Ogden, J.S.; Bowsher, B.R.

    1986-10-01

    Detailed assessments of hypothetical severe accidents in light water reactors require the identification of the chemical forms of the radionuclides in order to determine their transport characteristics. Caesium and tellurium are important volatile fission products in accident scenarios. This report describes detailed studies to characterise the chemical species that vaporise from heated mixtures of various alkali metal-tellurium-oxygen systems. The molecular species were characterised by a combination of quadrupole mass spectrometry and matrix isolation-infrared spectroscopy undertaken in conjunction with experiments involving oxygen-18 substitution. The resulting spectra were interpreted in terms of a vapour-phase molecule with the stoichiometry M 2 TeO 3 (M = K,Rb,Cs) for M/Te molecular ratios of ∼ 2, and polymeric species for ratios < 2. This work has demonstrated the stability of caesium tellurite. The formation of this relatively low-volatility, water-soluble species could significantly modify the transport and release of caesium and tellurium. The data presented in this report should allow more comprehensive thermodynamic calculations to be undertaken that assist in the quantification of fission product behaviour during severe reactor accidents. (author)

  12. 40K/137Cs discrimination ratios to the aboveground organs of tropical plants.

    Science.gov (United States)

    Sanches, N; Anjos, R M; Mosquera, B

    2008-07-01

    In the present work, the accumulation of caesium and potassium in aboveground plant parts was studied in order to improve the understanding on the behaviour of monovalent cations in several compartments of tropical plants. We present the results for activity concentrations of (137)Cs and (40)K, measured by gamma spectrometry, from five tropical plant species: guava (Psidium guajava), mango (Mangifera indica), papaya (Carica papaya), banana (Musa paradisíaca), and manioc (Manihot esculenta). Caesium and potassium have shown a high level of mobility within the plants, exhibiting the highest values of concentration in the growing parts (fruits, leaves, twigs, and barks) of the woody fruit and large herbaceous shrub (such as manioc) species. In contrast, the banana and papaya plants exhibited the lowest levels of (137)Cs and (40)K in their growing parts. However, a significant correlation between activity concentrations of (137)Cs and (40)K was observed in these tropical plants. The (40)K/(137)Cs discrimination ratios were approximately equal to unity in different compartments of each individual plant, suggesting the possibility of using caesium to predict the behaviour of potassium in several tropical species.

  13. A Novel Method for Remote Depth Estimation of Buried Radioactive Contamination.

    Science.gov (United States)

    Ukaegbu, Ikechukwu Kevin; Gamage, Kelum A A

    2018-02-08

    Existing remote radioactive contamination depth estimation methods for buried radioactive wastes are either limited to less than 2 cm or are based on empirical models that require foreknowledge of the maximum penetrable depth of the contamination. These severely limits their usefulness in some real life subsurface contamination scenarios. Therefore, this work presents a novel remote depth estimation method that is based on an approximate three-dimensional linear attenuation model that exploits the benefits of using multiple measurements obtained from the surface of the material in which the contamination is buried using a radiation detector. Simulation results showed that the proposed method is able to detect the depth of caesium-137 and cobalt-60 contamination buried up to 40 cm in both sand and concrete. Furthermore, results from experiments show that the method is able to detect the depth of caesium-137 contamination buried up to 12 cm in sand. The lower maximum depth recorded in the experiment is due to limitations in the detector and the low activity of the caesium-137 source used. Nevertheless, both results demonstrate the superior capability of the proposed method compared to existing methods.

  14. Express-analysis of Radiocaesium Traces in Natural Water

    International Nuclear Information System (INIS)

    Remez, V.P.; Belyakova, E.G.

    1999-01-01

    To determine traces of radiocaesium in water solution, the sorbent on the base of ferric potassium hexacyanoferrate on cellulose carrier ANFEZH was worked out. The sorbent is capable to extract effectively the isotopes of caesium from various natural solutions (fresh and sea water, milk, juices and so on). The usage of sorbent allows practically completely concentrate the isotopes of caesium from water samples with the volume of tens and hundreds litres. The sorbent in quantity of 50-500 grams allows to extract 98±1% of caesium from natural water samples with the volume up to 1000 litres during 1-5 hours. The usage of this sorbent allowed to conduct the express analysis of multiple bore holes within the area of 30 km of Chernobyl Skaya NPP , drinking water and milk in the regions of Belorussia, Ukraine and Russia, hit by Chernobyl disaster and around NPP in Russia and America. The use of this express analysis reduced the time and required labour as compared with to precipitation methods

  15. Radioactive fallout in air and rain: results to end of 1980

    International Nuclear Information System (INIS)

    Cambray, R.S.; Fisher, E.M.R.; Playford, K.; Eakins, J.D.; Peirson, D.H.

    1981-06-01

    Samples of atmospheric dust and rainwater have been collected from the United Kingdom and elsewhere. Results are presented of analyses of these samples for various fission products and certain other radionuclides. The average concentrations of long-lived fission products in air and rain in the United Kingdom in 1980 were about two thirds those in 1979 and less than 1% of the maximum which was reached in 1963-64. Plutonium concentrations in air and rainwater generally follow the pattern of long-lived fission products. Barium-140 and iodine-131, indicative of a recent atmospheric test were detected in the atmosphere in the United Kingdom after the intermediate yield Chinese explosion of 16 October 1980. At the end of 1980 about half the caesium-137 in air near ground level in the United Kingdom was attributable to that explosion. In the southern hemisphere the mean concentration of caesium-137 in air in 1980 was similar to that in 1979. An estimate is made of the worldwide deposit of caesium-137 and strontium-90. The gamma and beta-ray dose rates from fallout at Chilton are estimated from the observed deposition. (author)

  16. The removal of 134Cs from radioactive process waste water by coprecipitate flotation

    International Nuclear Information System (INIS)

    Aziz, M.; Shakir, K.; Benyamin, K.

    1986-01-01

    The coprecipitate flotation of 134 Cs from radioactive process waste water using copper ferrocyanide as a coprecipitating agent and sodium lauryl sulphate, cetyl trimethyl ammonium bromide or gelatin as collector was extensively investigated to establish the best conditions for caesium removal with each of the collectors under test. The investigated parameters include the collector dosage, the Cu 2+ /Fe(CN) 6 4- ratio, the caesium, potassium, sodium and calcium ion concentrations, the ageing time period of the Cu 2+ - Fe(CN) 6 4- - 134 Cs - water system and the bubbling time duration. The results indicate that copper ferrocyanide has a high affinity for caesium and can preferentially co-precipitate it in presence of relatively high amounts of other alkali or alkaline earth cations. For the alkali metals the affinity increases in the order Na < K < Cs. Under the optimal conditions removals higher than 99% could be achieved with any of the tested collectors. The results are discussed in terms of the ion exchange properties of copper ferrocyanide and collector behaviour. Advantages of the coflotation technique over other methods are enumerated. (Auth.)

  17. Modelling of radionuclide migration in forest ecosystems. A literature review

    Energy Technology Data Exchange (ETDEWEB)

    Avila, R.; Moberg, L.; Hubbard, L.

    1998-03-01

    The Chernobyl accident has clearly shown the long-term effects of a radioactive contamination of forest ecosystems. This report is based on a literature review of models which describe the migration of radionuclides, radioactive caesium in particular, in forest ecosystems. The report describes the particularities of the forest ecosystem, the time dynamics of the contamination, the transfer processes and factors influencing caesium migration. This provides a basis for a discussion of different approaches for modelling caesium migration in the forest. It is concluded that the studied dynamic models include the most relevant transfer processes both for the acute and the long-term phase after a radioactive deposition. However, most models are site specific and do not consider some of the factors responsible for the differences in radionuclide behaviour and distribution in different types of forests. Although model improvements are constrained by the availability of experimental data and by the lack of knowledge of the migration mechanisms some possible improvements are discussed. This report is part of the LANDSCAPE project. -An integrated approach to radionuclide flow in the semi-natural ecosystems underlying exposure pathways to man. 42 refs, 3 tabs, 9 figs.

  18. Modelling of radionuclide migration in forest ecosystems. A literature review

    International Nuclear Information System (INIS)

    Avila, R.; Moberg, L.; Hubbard, L.

    1998-03-01

    The Chernobyl accident has clearly shown the long-term effects of a radioactive contamination of forest ecosystems. This report is based on a literature review of models which describe the migration of radionuclides, radioactive caesium in particular, in forest ecosystems. The report describes the particularities of the forest ecosystem, the time dynamics of the contamination, the transfer processes and factors influencing caesium migration. This provides a basis for a discussion of different approaches for modelling caesium migration in the forest. It is concluded that the studied dynamic models include the most relevant transfer processes both for the acute and the long-term phase after a radioactive deposition. However, most models are site specific and do not consider some of the factors responsible for the differences in radionuclide behaviour and distribution in different types of forests. Although model improvements are constrained by the availability of experimental data and by the lack of knowledge of the migration mechanisms some possible improvements are discussed. This report is part of the LANDSCAPE project. -An integrated approach to radionuclide flow in the semi-natural ecosystems underlying exposure pathways to man

  19. Progress of the ELISE test facility: towards one hour pulses in hydrogen

    Science.gov (United States)

    Wünderlich, D.; Fantz, U.; Heinemann, B.; Kraus, W.; Riedl, R.; Wimmer, C.; the NNBI Team

    2016-10-01

    In order to fulfil the ITER requirements, the negative hydrogen ion source used for NBI has to deliver a high source performance, i.e. a high extracted negative ion current and simultaneously a low co-extracted electron current over a pulse length up to 1 h. Negative ions will be generated by the surface process in a low-temperature low-pressure hydrogen or deuterium plasma. Therefore, a certain amount of caesium has to be deposited on the plasma grid in order to obtain a low surface work function and consequently a high negative ion production yield. This caesium is re-distributed by the influence of the plasma, resulting in temporal instabilities of the extracted negative ion current and the co-extracted electrons over long pulses. This paper describes experiments performed in hydrogen operation at the half-ITER-size NNBI test facility ELISE in order to develop a caesium conditioning technique for more stable long pulses at an ITER relevant filling pressure of 0.3 Pa. A significant improvement of the long pulse stability is achieved. Together with different plasma diagnostics it is demonstrated that this improvement is correlated to the interplay of very small variations of parameters like the electrostatic potential and the particle densities close to the extraction system.

  20. The Effective Dose Due to Radionuclides Intake Via Ingestion in Poland in 1986-1999

    International Nuclear Information System (INIS)

    Grabowski, D.; Kurowski, W.; Muszynski, W.; Rubel, B.; Swietochowska, J.

    2001-01-01

    Full text: One of the pathways of radiation exposure in humans is consumption of contaminated food. The composition of an average diet is diversified for various groups within the population and depends on age, sex, consumption habit and performed work. To asses the dose obtained by people due to ingestion of contaminated food, the activity of main products of Polish diet has been analysed for period 1986 - 1999. The samples of milk, meat, vegetables, fruit and cereals were collected all over the territory of Poland to determine the activity of caesium isotopes. In the first two-year after the Chernobyl accident the differences in contamination were observed in various regions. Later on the differences were less pronounced except in milk and meat. The calculation of an average annual intake of caesium isotopes was based on statistical data consumption and contamination of certain product important in daily diet. Annual intake of caesium was different among regions. Mean annual effective dose related to the ingestion of contaminated food of 137 Cs was assessed on 54μSv in 1986 and 28μSv in 1987 and of 134 Cs on 34μSv and 13μSv respectively. In next years the dose was diminishing and from 1993 the average annual effective dose from 137 Cs has been on level 6-7 μSv. (author)