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Sample records for artificial radionuclides behavior

  1. Radionuclide behavior at underground environment

    Energy Technology Data Exchange (ETDEWEB)

    Hahn, Phil Soo; Park, Chung Kyun; Keum, Dong Kwon; Cho, Young Hwan; Kang, Moon Ja; Baik, Min Hoon; Hahn, Kyung Won; Chun, Kwan Sik; Park, Hyun Soo

    2000-03-01

    This study of radionuclide behavior at underground environment has been carried out as a part of the study of high-level waste disposal technology development. Therefore, the main objectives of this project are constructing a data-base and producing data for the safety assessment of a high-level radioactive waste, and verification of the objectivity of the assessment through characterization of the geochemical processes and experimental validation of the radionuclide migration. The various results from the this project can be applicable to the preliminary safety and performance assessments of the established disposal concept for a future high-level radioactive waste repository. Providing required data and technical basis for assessment methodologies could be a direct application of the results. In a long-term view, the results can also be utilized as a technical background for the establishment of government policy for high-level radioactive waste disposal.

  2. Radionuclide behavior in the environment

    International Nuclear Information System (INIS)

    Tveten, U.

    1991-09-01

    The purpose of this report is to document the results of the following task: Review for quality and consistency the available data on measurements of initial ground contamination of Chernobyl radionuclides in various parts of Norway and subsequent concentrations of these radionuclides in various environmental media as functions of time. Utilize the data obtained to verify the existing models, or to improve them, for describing radionuclide behavior in the environment. Some of the processes standard were: migration into soil; weathering; resuspension; food-chain contamination; and loss or reconcentration by run-off. The task performed within this contract has been to use post-Chernobyl data from Norway to verify or find areas for possible improvement in the chronic exposure pathway models utilized in MACCS. Work has consisted mainly of collecting and evaluating post-Chernobyl information from Norway or other countries when relevant; but has also included experimental work performed specifically for the current task. In most connections the data available show the models and data in MACCS to be appropriate. A few areas where the data indicate that the MACCS approach is faulty or inadequate are, however, pointed out in the report. These should be examined carefully, and appropriate modifications should eventually be made. 14 refs., 12 figs., 22 tabs

  3. A comparison of the dose from natural radionuclides and artificial radionuclides after the Fukushima nuclear accident.

    Science.gov (United States)

    Hosoda, Masahiro; Tokonami, Shinji; Omori, Yasutaka; Ishikawa, Tetsuo; Iwaoka, Kazuki

    2016-07-01

    Due to the Fukushima Daiichi Nuclear Power Plant (FDNPP) accident, the evacuees from Namie Town still cannot reside in the town, and some continue to live in temporary housing units. In this study, the radon activity concentrations were measured at temporary housing facilities, apartments and detached houses in Fukushima Prefecture in order to estimate the annual internal exposure dose of residents. A passive radon-thoron monitor (using a CR-39) and a pulse-type ionization chamber were used to evaluate the radon activity concentration. The average radon activity concentrations at temporary housing units, including a medical clinic, apartments and detached houses, were 5, 7 and 9 Bq m(-3), respectively. Assuming the residents lived in these facilities for one year, the average annual effective doses due to indoor radon in each housing type were evaluated as 0.18, 0.22 and 0.29 mSv, respectively. The average effective doses to all residents in Fukushima Prefecture due to natural and artificial sources were estimated using the results of the indoor radon measurements and published data. The average effective dose due to natural sources for the evacuees from Namie Town was estimated to be 1.9 mSv. In comparison, for the first year after the FDNPP accident, the average effective dose for the evacuees due to artificial sources from the accident was 5.0 mSv. Although residents' internal and external exposures due to natural radionuclides cannot be avoided, it might be possible to lower external exposure due to the artificial radionuclides by changing some behaviors of residents. © The Author 2016. Published by Oxford University Press on behalf of The Japan Radiation Research Society and Japanese Society for Radiation Oncology.

  4. Radionuclide behavior at underground environment

    International Nuclear Information System (INIS)

    Hahn, Phil Soo; Park, Chung Kyun; Keum, Dong Kwon; Cho, Young Hwan; Kang, Moon Ja; Baik, Min Hoon; Hahn, Kyung Won; Park, Hyun Soo

    2003-04-01

    This study of radionuclide behavior at underground environment has been carried out as a part of the study of high-level waste disposal technology development. Therefore, the main objectives of this project are constructing a data-base and producing data for the safety assessment of a high-level radioactive waste, and verification of the objectivity of the assessment through characterization of the geochemical processes and experimental validation of the radionuclide migration. This project is composed of 6 subjects such as data production required for safety assessments, sorption properties and mechanisms, nuclide migration in the fractured rock, colloid formation and migration, nuclide speciation in deep geological environments, and total evaluation of geochemical behaviors considering multi-factors. The various results from the this project can be applicable to the preliminary safety and performance assessments of the established disposal concept for a future high-level radioactive waste repository. Providing required data and technical basis for assessment methodologies could be a direct application of the results. In a long-term view, the results can also be utilized as a technical background for the establishment of government policy for high-level radioactive waste disposal

  5. Artificial radionuclides in the atmosphere over Lithuania

    International Nuclear Information System (INIS)

    Lujaniene, G.; Sapolaite, J.; Remeikis, V.; Lujanas, V.; Aninkevicius, V.

    2006-01-01

    Systematic observations of radionuclide composition and concentration in the atmosphere have been carried out at the Institute of Physics in Vilnius since 1963. An increase in activity concentration of radionuclides in the atmosphere was observed after nuclear weapon tests and the Chernobyl NPP accident. At present the radiation situation in Lithuania is determined by two main sources of radionuclides, forest fire and resuspension products transferred from highly polluted region of the Ukraine and Belarus. During forest fires the increase in activity concentration of 1 37Cs in the atmosphere was registered in many countries and in Lithuania as well. This work summarizes the experimental data on transport of cesium, plutonium, americium from the highly contaminated territories after the Chernobyl accident. The activity concentrations of 1 37Cs were measured in two - three days samples while plutonium and americium in monthly samples. In addition, the analyses of the events of the increase activity concentration, meteorological situation, speciation of radionuclides and mechanisms of formation and transformation of aerosol carriers of radionuclides are presented. Aerosols were sampled on perchlorvinyl filters and the large volume air samplers with a flow rate from 2400 m 3 /h to about 6000 m 3 /h were used. The radiochemical analyses of monthly samples of aerosol ashes (about 30 g) were performed. For separation of Pu isotopes the TOPO/cyclohexane extraction and radiochemical purification using UTEVA resin were performed, Am was separated after TOPO/cyclohexane extraction using TRU and TEVA resins (100-150 μm). 2 42Pu and 2 43Am were used as tracers in the separation procedure. The alpha spectrometry measurements of Pu and Am isotopes deposited on a stainless steel disc were carried out with the Alphaquattro (Silena) spectrometer. 1 37Cs was determined by gamma-ray spectrometry using the high purity HPGe detector (resolution - 1.9 keV/1.33 Mev, efficiency - 42

  6. HUMAN EXPOSURE TO THE ARTIFICIAL RADIONUCLIDES IN ENVIRONMENT

    Directory of Open Access Journals (Sweden)

    Ivana Vukanac

    2012-09-01

    Full Text Available Artificial radionuclides are product of different human activities and their presence in the environment is negative side effect of civilization progress. They have been spread in the environment by events such as nuclear weapon tests, nuclear accidents and by deliberate and negligent discharge of radioactive waste from nuclear and other installation. Once released in to the nature, the artificial radionuclides start to circle in the same manner as naturally occurring ones, and finally they fall out from air and water onto the ground and build into the foodstuff and drinking water resulting in radiation doses to human beings. The short overview of presence of artificial radioactivity in human environment and its impact on human life is presented in this paper.

  7. HUMAN EXPOSURE TO THE ARTIFICIAL RADIONUCLIDES IN ENVIRONMENT

    Directory of Open Access Journals (Sweden)

    Ivana Vukanac

    2012-09-01

    Full Text Available Artificial radionuclides are product of different human activities and their presence in the environment is negative side effect of civilization progress. They have been spread in the environment by events such as nuclear weapon tests, nuclear accidents and by deliberate and negligent discharge of radioactive waste from nuclear and other installation. Once released in to the nature, the artificial radionuclides start to circle in the same manner as naturally occurring ones, and finally they fall out from air and water onto the ground and build into the foodstuff and drinking water resulting in radiation doses to human beings. The short overview of presence of artificial radioactivity in human environment and its impact on human life is presented in this paper

  8. Natural and artificial radionuclides in lichens as air pollution monitors

    International Nuclear Information System (INIS)

    Jeran, A.; Jacimovic, R.; Prosenc, A.; Batic, F.

    1996-01-01

    In 1992 a national biomonitoring programme was initiated covering the whole territory of Slovenia to measure the levels of some natural ( 210 Pb, 40 K, U, Th) and artificial ( l37 Cs, 134 Cs) radionuclides in the epiphytic lichen Hypogymnia physodes L. (Nyl.) in order to obtain information on their levels in the environment. 210 Pb, 40 K, 134,137 Cs were determined by direct counting of dry samples using gamma spectrometry, while U and Th were determined by the k 0 -standardisation method of instrumental neutron activation analysis (INAA). The results are presented as geographical isocontours of radionuclide activity on a national scale. (author)

  9. Artificial Radionuclides Database in the Pacific Ocean: HAM Database

    Directory of Open Access Journals (Sweden)

    Michio Aoyama

    2004-01-01

    Full Text Available The database “Historical Artificial Radionuclides in the Pacific Ocean and its Marginal Seas”, or HAM database, has been created. The database includes 90Sr, 137Cs, and 239,240Pu concentration data from the seawater of the Pacific Ocean and its marginal seas with some measurements from the sea surface to the bottom. The data in the HAM database were collected from about 90 literature citations, which include published papers; annual reports by the Hydrographic Department, Maritime Safety Agency, Japan; and unpublished data provided by individuals. The data of concentrations of 90Sr, 137Cs, and 239,240Pu have been accumulating since 1957–1998. The present HAM database includes 7737 records for 137Cs concentration data, 3972 records for 90Sr concentration data, and 2666 records for 239,240Pu concentration data. The spatial variation of sampling stations in the HAM database is heterogeneous, namely, more than 80% of the data for each radionuclide is from the Pacific Ocean and the Sea of Japan, while a relatively small portion of data is from the South Pacific. This HAM database will allow us to use these radionuclides as significant chemical tracers for oceanographic study as well as the assessment of environmental affects of anthropogenic radionuclides for these 5 decades. Furthermore, these radionuclides can be used to verify the oceanic general circulation models in the time scale of several decades.

  10. Monitoring of natural and artificial radionuclides in Thrace Region by using bio indicator organisms

    International Nuclear Information System (INIS)

    Belivermis, M.; Kilic, O.; Cotuk, Y.; Topcuoglu, S.

    2009-01-01

    Moss and lichen have been used commonly as bio indicators of fall-out radionuclides such as 1 37Cs and naturally occurring radionuclides such as 7 Be, 2 32Th, 2 38U. Moss and lichens have crucial advantages for determining atmospheric fall-out radionuclides with regard to vascular plants because of great surface/volume ratio, lack of cuticle and well developed root systems. 1 37Cs considered as one of the most hazardous artificial radionuclides in the environment because of its similar physicochemical properties to potassium and long physical half-life (30.14 years). 1 37Cs accumulation studies in moss and lichen are useful because of the reflect atmospheric deposition. In addition to 1 37Cs, the behavior of natural radionuclides in the terrestrial ecosystems has been the centre of attraction for radioecology studies in view of their toxic influences on the human by entering food chains. It is noted in the literature that, recently, concentrations of terrestrial radionuclides have been increased in biota as a result of fossil fuel combustion. In the current study, 1 37Cs, 4 0K, 2 32Th and 2 38U radioactivity concentrations of moss, lichen and pine bark samples which were collected from Thrace Region were measured by using gamma spectrometry equipped with high-purity germanium detector. The activity concentrations of 1 37Cs, 4 0K, 2 32Th and 2 38U in the moss samples found in the range of 0.36-8.13, 85.4-162.9, 1.62-6.17, 1.69-6.73 Bq kg - 1, respectively.

  11. The effects of radionuclides on animal behavior

    International Nuclear Information System (INIS)

    Gagnaire, B.; Adam-Guillermin, C.; Bouron, A.; Lestaevel, P.

    2011-01-01

    to increased suicides, as well as modification of preferred nesting sites, reduced hatching success and fecundity in birds that live in the Chernobyl zone. No significant effect from caesium exposure was shown in laboratory experiments with rats, but few studies were conducted. Data on radioactive cadmium are not available in the literature, but the effects of its metallic form have been well studied. Cadmium induces mental retardation and psychomotor alterations in exposed populations and increases anxiety in rats, leading to depression. Cadmium exposure also results in well-documented effects on feeding and burrowing behavior in several invertebrate species (crustaceans, gastropods, annelids, bivalves) and on different kinds of fish behavior (swimming activity, fast-start response, anti-predatory behavior). Cobalt induces memory deficits in humans and may be involved in Alzheimer's disease; gamma irradiation by cobalt also decreases fecundity and alters mating behavior in insects. Collectively, data are lacking or are meagre on radionuclide pollutants, and a better knowledge of their actions on the cellular and molecular mechanisms that control animal behavior is needed. (authors)

  12. Distribution of natural and artificial radionuclides in chernozem soil/crop system from stationary experiments.

    Science.gov (United States)

    Sarap, Nataša B; Rajačić, Milica M; Đalović, Ivica G; Šeremešić, Srđan I; Đorđević, Aleksandar R; Janković, Marija M; Daković, Marko Z

    2016-09-01

    The present paper focuses on the determination of radiological characteristics of cultivated chernozem soil and crops from long-term field experiments, taking into account the importance of distribution and transfer of radionuclides in the soil-plant system, especially in agricultural cropland. The investigation was performed on the experimental fields where maize, winter wheat, and rapeseed were cultivated. Analysis of radioactivity included determination of the gross alpha and beta activity as a screening method, as well as the activities of the following radionuclides: natural ((210)Pb, (235)U, (238)U, (226)Ra, (232)Th, (40)K, (7)Be) and artificial ((90)Sr and (137)Cs). The activities of natural and artificial ((137)Cs) radionuclides were determined by gamma spectrometry, while the artificial radionuclide (90)Sr was determined by a radiochemical analytical method. Based on the obtained results for the specific activity of (40)K, (137)Cs, and (90)Sr, accumulation factors for these radionuclides were calculated in order to estimate transfer of radionuclides from soil to crops. The results of performed analyses showed that there is no increase of radioactivity that could endanger the food production through the grown crops.

  13. Arctic Ocean sea ice drift origin derived from artificial radionuclides

    International Nuclear Information System (INIS)

    Camara-Mor, P.; Masque, P.; Garcia-Orellana, J.; Cochran, J.K.; Mas, J.L.; Chamizo, E.; Hanfland, C.

    2010-01-01

    Since the 1950s, nuclear weapon testing and releases from the nuclear industry have introduced anthropogenic radionuclides into the sea, and in many instances their ultimate fate are the bottom sediments. The Arctic Ocean is one of the most polluted in this respect, because, in addition to global fallout, it is impacted by regional fallout from nuclear weapon testing, and indirectly by releases from nuclear reprocessing facilities and nuclear accidents. Sea-ice formed in the shallow continental shelves incorporate sediments with variable concentrations of anthropogenic radionuclides that are transported through the Arctic Ocean and are finally released in the melting areas. In this work, we present the results of anthropogenic radionuclide analyses of sea-ice sediments (SIS) collected on five cruises from different Arctic regions and combine them with a database including prior measurements of these radionuclides in SIS. The distribution of 137 Cs and 239,240 Pu activities and the 240 Pu/ 239 Pu atom ratio in SIS showed geographical differences, in agreement with the two main sea ice drift patterns derived from the mean field of sea-ice motion, the Transpolar Drift and Beaufort Gyre, with the Fram Strait as the main ablation area. A direct comparison of data measured in SIS samples against those reported for the potential source regions permits identification of the regions from which sea ice incorporates sediments. The 240 Pu/ 239 Pu atom ratio in SIS may be used to discern the origin of sea ice from the Kara-Laptev Sea and the Alaskan shelf. However, if the 240 Pu/ 239 Pu atom ratio is similar to global fallout, it does not provide a unique diagnostic indicator of the source area, and in such cases, the source of SIS can be constrained with a combination of the 137 Cs and 239,240 Pu activities. Therefore, these anthropogenic radionuclides can be used in many instances to determine the geographical source area of sea-ice.

  14. Establishment and application of a large calibration device of artificial radionuclide plane source

    International Nuclear Information System (INIS)

    Hu Mingkao; Zhang Jiyun; Wang Xinxing; Zhang Sheng

    2010-01-01

    With the expansion of the application fields of nuclear techniques and the development of economy, more and more airborne/vehicle and other large γ spectrometers are applied in the environment radiation monitoring of artificial radioactive nuclides. In order to ensure the reliability of the monitoring results, a large calibration device of artificial radionuclide plane source is established. The paper introduces the device's built history and the results of application. (authors)

  15. Inventory and application of artificial radionuclides in France

    International Nuclear Information System (INIS)

    Besson, J.P.; Hoorelbeke, A.

    1998-01-01

    A number of regulations were completed with the aim to ensure safe storage and application of radionuclides in France, especially taking into account radiation protection. CIREA guarantees their unanimity by its judgement on the general questions arising from application of regulations. It has a regulatory role since it requires special conditions for particular practices. Authorisation for induction of radioactive sources or equipment containing sources, their application, storage, etc. are directly given by CIREA or after having obtained its premises

  16. Natural and artificial radionuclides in southern of Gulf of Mexico marine sediments

    International Nuclear Information System (INIS)

    Rodriguez-Espinosa, P.F.; Vidal-Lorandi, V.M.V.; Vidal-Lorandi, F.V.

    1999-01-01

    Preliminary results of quantitative analysis of natural and artificial radionuclides in sediment cores of the Southern Gulf of Mexico, reveal the presence of 22.01 Bq/kg 226 Ra, 15.56 Bq/kg 214 Bi, 18.17 Bq/kg 214 Pb, 485.81 Bq/kg 40 K and 2.84 Bq/kg 137 Cs

  17. Arctic Ocean sea ice drift origin derived from artificial radionuclides.

    Science.gov (United States)

    Cámara-Mor, P; Masqué, P; Garcia-Orellana, J; Cochran, J K; Mas, J L; Chamizo, E; Hanfland, C

    2010-07-15

    Since the 1950s, nuclear weapon testing and releases from the nuclear industry have introduced anthropogenic radionuclides into the sea, and in many instances their ultimate fate are the bottom sediments. The Arctic Ocean is one of the most polluted in this respect, because, in addition to global fallout, it is impacted by regional fallout from nuclear weapon testing, and indirectly by releases from nuclear reprocessing facilities and nuclear accidents. Sea-ice formed in the shallow continental shelves incorporate sediments with variable concentrations of anthropogenic radionuclides that are transported through the Arctic Ocean and are finally released in the melting areas. In this work, we present the results of anthropogenic radionuclide analyses of sea-ice sediments (SIS) collected on five cruises from different Arctic regions and combine them with a database including prior measurements of these radionuclides in SIS. The distribution of (137)Cs and (239,240)Pu activities and the (240)Pu/(239)Pu atom ratio in SIS showed geographical differences, in agreement with the two main sea ice drift patterns derived from the mean field of sea-ice motion, the Transpolar Drift and Beaufort Gyre, with the Fram Strait as the main ablation area. A direct comparison of data measured in SIS samples against those reported for the potential source regions permits identification of the regions from which sea ice incorporates sediments. The (240)Pu/(239)Pu atom ratio in SIS may be used to discern the origin of sea ice from the Kara-Laptev Sea and the Alaskan shelf. However, if the (240)Pu/(239)Pu atom ratio is similar to global fallout, it does not provide a unique diagnostic indicator of the source area, and in such cases, the source of SIS can be constrained with a combination of the (137)Cs and (239,240)Pu activities. Therefore, these anthropogenic radionuclides can be used in many instances to determine the geographical source area of sea-ice. Copyright 2010 Elsevier B.V. All

  18. Bioconcentration of artificial radionuclides in edible mushrooms: in situ and in vitro studies

    Energy Technology Data Exchange (ETDEWEB)

    Dementyev, Dmitry V.; Manukovsky, Nikolai S.; Bolsunovsky, Alexander Ya.; Alexandrova, Yuliyana V. [Institute of Biophysics, Siberian Branch of the Russian Academy of Sciences, 660036, Krasnoyarsk (Russian Federation)

    2014-07-01

    Some areas of the Yenisei River basin are affected by the operation of the Mining-and-Chemical Combine (MCC), producing weapons-grade plutonium. Flood plain soils of the Yenisei contain a wide range of artificial radionuclides, including transuranium elements, which can be accumulated by living organisms. Concentrations of artificial radionuclides and heavy metals accumulated by mushrooms may be several orders of magnitude higher than those accumulated by plants, and, thus, mushrooms may be used as bio-concentrators of radionuclides and heavy metals for bioremediation of contaminated areas. The purposes of this study were to investigate 1) species specificity of accumulation of artificial radionuclides by edible mushrooms in radioactively contaminated areas of the Yenisei River flood plain and 2) accumulation rates of artificial radionuclides, including transuranium elements, in mushrooms under laboratory conditions. Species specificity of accumulation of artificial radionuclides and uranium by mushrooms was analyzed for 12 species of edible mushrooms. The study was performed at the sites affected by MCC operation, which were divided into two groups: 1) the sites only affected by aerosol-bound radionuclides and 2) the sites that also received waterborne radionuclides. Field studies showed great interspecific variations in Cs-137 accumulation by mushrooms. Activity concentrations of Cs-137 in bioindicator species Suillus granulatus and S. Luteus reached 10 kBq/kg dry weight. S. granulatus and S. luteus are concentrators of Cs-137, as suggested by the analysis of concentration factors (CFs), which reached 0.7-16 for these mushroom species. The CF of U-238 in fruiting bodies of the mushrooms was no greater than 0.11. Yenisei flood plain soils contain a wide range of transuranium elements, which can accumulate in environmental objects. Laboratory experiments on accumulation of Am-241 from solution by mycelium and Am-241 accumulation by fruiting bodies of mushrooms

  19. Distribution of artificial radionuclides in deep sediments of the Mediterranean Sea

    International Nuclear Information System (INIS)

    Garcia-Orellana, J.; Pates, J.M.; Masque, P.; Bruach, J.M.; Sanchez-Cabeza, J.A.

    2009-01-01

    Artificial radionuclides enter the Mediterranean Sea mainly through atmospheric deposition following nuclear weapons tests and the Chernobyl accident, but also through the river discharge of nuclear facility effluents. Previous studies of artificial radionuclides impact of the Mediterranean Sea have focussed on shallow, coastal sediments. However, deep sea sediments have the potential to store and accumulate pollutants, including artificial radionuclides. Deep sea marine sediment cores were collected from Mediterranean Sea abyssal plains (depth > 2000 m) and analysed for 239,240 Pu and 137 Cs to elucidate the concentrations, inventories and sources of these radionuclides in the deepest areas of the Mediterranean. The activity - depth profiles of 210 Pb, together with 14 C dating, indicate that sediment mixing redistributes the artificial radionuclides within the first 2.5 cm of the sedimentary column. The excess 210 Pb inventory was used to normalize 239,240 Pu and 137 Cs inventories for variable sediment fluxes. The 239,240 Pu/ 210 Pb xs ratio was uniform across the entire sea, with a mean value of 1.24 x 10 -3 , indicating homogeneous fallout of 239,240 Pu. The 137 Cs/ 210 Pb xs ratio showed differences between the eastern (0.049) and western basins (0.030), clearly significant impact of deep sea sediments from the Chernobyl accident. The inventory ratios of 239,240 Pu/ 137 Cs were 0.041 and 0.025 in the western and eastern basins respectively, greater than the fallout ratio, 0.021, showing more efficient scavenging of 239,240 Pu in the water column and major sedimentation of 137 Cs in the eastern basin. Although areas with water depths of > 2000 m constitute around 40% of the entire Mediterranean basin, the sediments in these regions only contained 2.7% of the 239,240 Pu and 0.95% of the 137 Cs deposited across the Sea in 2000. These data show that the accumulation of artificial radionuclides in deep Mediterranean environments is much lower than predicted by

  20. Behaviour and fate of artificial redionuclides in the marine environment

    International Nuclear Information System (INIS)

    1979-01-01

    Behaviour of artificial radionuclides in the marine environment, effect of the physico-chemical forms of the radionuclides. Behavior of radionuclides in the physical and biological environments and general evaluation of transfers [fr

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2014-07-01

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

  2. A field study of physico-chemical states of artificial radionuclides in seawater

    International Nuclear Information System (INIS)

    Nagaya, Yutaka; Nakamura, Kiyoshi

    1974-01-01

    The physico-chemical states of artificial radionuclides, 90 Sr, 137 Cs and 144 Ce in seawater were investigated by radiochemical analysis of filtered and unfiltered seawater. The difference of radionuclide concentrations between unfiltered and filtered seawaters was defined as the ''particulate form'' radioisotope and its ''particle ratio'' was discussed. Practically no particulate 90 Sr, greater than 0.22 μ in size, was observed in both coastal and open seawaters, but some of 137 Cs seemed to be insoluble in some circumstances, especially in coastal waters. A considerable amount of 144 Ce was found to be particulate. An estimation of the radionuclides in particulate form was made for Kashima-nada seawaters collected in 1970 to 1972, and it was shown that the possible occurrence of particulate radionuclides, greater than 0.22 μ in size, were 1% or less for 90 Sr and 6% for 137 Cs. In the coastal water, 80% of 144 Ce were seemed to be in particulate form, but in the open seawater only a few %. The influences of suspended materials to 137 Cs and 144 Ce concentration levels in seawater were not negligible and further investigations are desirable. (auth.)

  3. Depositional history of artificial radionuclides in the Ross Ice Shelf, Antarctica

    International Nuclear Information System (INIS)

    Koide, M.; Michel, R.; Goldberg, E.D.; Herron, M.M.; Langway, C.C. Jr.

    1979-01-01

    The annual fluxes of artificial radionuclides ( 238 Pu, sup(239 + 240)Pu, 241 Am, 137 Cs, 90 Sr and 3 H) from the atmosphere to the Ross Ice Shelf in Antarctica were determined from measurements in strata dated by 201 Pb. Recognizable sources include the U.S tests (Mike-Ivy and Castle Hill) in the early 1950s, the U.S.S.R. tests of the early 1960s, the SNAP-9A burnup of 1964 and the French and Chinese tests in the late 1960s and 1970s. There are several problems still awaiting resolution: the differences in atmospheric chemistries of fission products and of transuranics produced in weapons tests and the anomalous fluxes of 238 Pu to the ice shelf which do not appear to reflect a one-year stratospheric residence. There is no evidence for a smearing of the fallout record as a consequence of diffusion of these radionuclides in the glacial column. (Auth.)

  4. Preliminary results on accumulation and loss of artificial radionuclides in marine benthic algae

    International Nuclear Information System (INIS)

    Santos, P.L. dos; Santos Gouvea, R.C.; Gusmao Pedrini, A.

    1978-01-01

    The acummulation and the loss of artificial radionuclides in three species of marine benthic algae of the state of Rio de Janeiro were studied under laboratory conditions, so that a selection of biological indicators for radioctive contamination of the marine environment could be made. Medium concentration factors were calculated, the most significant figures being those obtained for the algae Pterocladia Capillacea (Gmelin) Bornet et Thuret (132+-40) p/ sub(131) I and Sargassum vulgares J. Agardh (19+-5) p/ 51 Cr [pt

  5. Prominent artificial radionuclide activity in the environment of coastal Karnataka on the southwest coast of India

    Energy Technology Data Exchange (ETDEWEB)

    Narayana, Y. [Department of Studies in Physics, Mangalore University, Mangalagangotri-574 199 (India)]. E-mail: narayanay@yahoo.com; Somashekarappa, H.M.; Karunakara, N.; Avadhani, D.N.; Mahesh, H.M.; Siddappa, K. [Department of Studies in Physics, Mangalore University, Mangalagangotri-574 199 (India)

    2000-09-01

    Studies on radiation level and radionuclide distribution in the environment of coastal Karnataka were undertaken to provide baseline data for the future assessment of the impact of the nuclear and thermal power stations that are being set up in the region and to understand the behaviour of radionuclides in the environment. As part of the programme the concentrations of two important artificial radionuclides, namely {sup 90}Sr and {sup 137}Cs, have been measured in a number of environmental samples. The concentration of {sup 90}Sr is very low in most of the samples. Among the samples analysed for the concentration of {sup 137}Cs, soil samples showed elevated levels of activity in some sampling stations. Among the vegetables, brinjal (Solanum melongena. L) showed considerable activity. The internal dose due to intake of {sup 90}Sr through diet was 0.42 {mu}Sv year{sup -1} for the vegetarian population and 0.32 {mu}Sv year{sup -1} for the non-vegetarian population. The internal dose due to dietary intake of {sup 137}Cs was found to be 0.34 {mu}Sv year{sup -1} and 0.26 {mu}Sv year{sup -1} respectively for the vegetarian and non-vegetarian population. The results are discussed in the light of the literature values reported for other environs of India and abroad and appropriate inferences are drawn. (author)

  6. Determination of natural and artificial radionuclides in 3 earner ecosystems (Alcocebre; Vinaroz and Vandellos)

    International Nuclear Information System (INIS)

    Navarro, E.; Roldan, C.; Sanchez, E.

    1998-01-01

    The knowledge of the environmental radioactivity level represents one of the main objectives at the moment for the environmental investigation. To check the existence of possible polluting sources and their impact in the population is of high-priority interest. We have intended to check the existence or not of radioactive pollutants in bio-indicators (algae, limpets and mussels) of the marine environment of three towns located in the Mediterranean coast: Alcocebre and Vinaroz in the county of Castellon and Vandellos in the county of Tarragona where a nuclear group is located for electric power production. The specific activity measurement carried out during the biennium 1996-97 of the natural gamma emitters ''228 Ac (''232Th series), ''226Ra (''238U series), ''235U, ''40K and ''7Be, and of the artificial radionuclides ''60Co, and ''137 Cs, it corroborates the character bio-accumulator of these organisms. Natural and artificial radionuclides have been detected in quantities without radiological significance. (Author) 3 Refs

  7. Inventory of artificial radionuclides in seawater and marine sediments from Southern coast of Brazil

    International Nuclear Information System (INIS)

    Figueira, Rubens Cesar Lopes

    2000-01-01

    /Sr-90 was in agreement. For plutonium, the fluctuation in its concentration is related to physical-chemical factors and its complex chemical behaviour, which act directly on the distribution of this element in solution. The results reached in the present work for the radionuclides levels were lower than those found in another regions of the world, as the European seas, subject to radioactive contamination from different sources, such as discharges from nuclear or reprocessing plants, dumping in the sea bottom and from Chernobyl nuclear accident, which increased significantly the contamination levels in the sea of this region. Thus, with the results here obtained, the inventory of the studied artificial radionuclides in the sediment was performed as well as the assessment of the artificial radioactive contamination in the Brazilian coast, since 1976 till 1997. Inventory values were lower than other regions of the world, directly affected by nuclear explosions or radioactive discharges. The results of the contamination assessment show a tendency to artificial radionuclide levels decreasing in this area, comparing data from 1986 to 1997. Furthermore, a survey on the total activity presented in the area was carried out and the following values for the marine sediments were found: (2.6 ± 1.3) TBq for Cs-137, (5.8 ± 4.5) TBq for Sr-90, (0.22 ± 0.16) TBq for Pu-239+240 and (0.19 ± 0.13) TBq for Pu-238. The seawater values were: (0.29± 0.15) PBq for Cs-137, (0.34± 0.25) PBq for Sr-90, (0.45 ± 0.41) TBq for Pu-239+240 and (0.15 ± 0.06) TBq for Pu-238. Therefore, the development of this work enabled our laboratory to the analysis of artificial radionuclides, important from the environmental point of view. The levels obtained are reference values and created a data bank, whose eventual changes will be attributed to a specific cause. Radionuclide levels here presented for Southern Brazilian coast are unpublished data as well as the values of inventory and the assessment

  8. Problems of dynamics radionuclides behavior in environment of Belarus

    International Nuclear Information System (INIS)

    Basharin, A.V.; Matveev, S.A.; Pushkareva, T.L.; Sharovarov, G.A.

    2003-01-01

    The experience of various methods application for radionuclide contaminated objects after the Chernobyl accident is considered. Methods useful to different objects, including kindergartens, are defined as a result of analysis. Methods of observation and control 134,137 Cs, 90 Sr and 238-240 Pu behavior in various environments are described. Value of the second air pollution after extraordinary situation at contaminated territories and object 'Ukryttia' is given. Dates of post-Chernobyl contamination of rivers and soils with radiocesium and radiostrontium, as well as deactivation of social objects are generalized

  9. The presence of some artificial and natural radionuclides in a Eucalyptus forest in the south of Spain

    International Nuclear Information System (INIS)

    Vaca, F.; Manjon, G.; Garcia-Leon, M.

    2001-01-01

    Long-lived artificial radionuclides ( 137 Cs, 90 Sr) were studied in a Eucalyptus plantation located in the south-west of Spain. Radionuclide concentrations were determined in different types of samples corresponding to specific forest components (soil, trees, herbs and litter). Depth profile distributions were obtained in two selected core soils. Two layers were separately measured in three other cores. The concentration factor, defined as the ratio between the mean activity concentration in a component and the mean activity concentration in the soil, was calculated for each component. The biomass of different components was estimated in order to evaluate the total density concentration (Bq/ha) of the artificial radionuclides ( 137 Cs, 90 Sr) in the Eucalyptus plantation. The transfer of the radionuclides between the different forest components can be inferred from the results. Additionally, other naturally occurring radionuclides ( 40 K, 226 Ra, 228 Ra, 228 Ac) were determined for comparison. Transport of radionuclides from forest to a nearby pulp mill is also discussed

  10. Radiological Assessment of the Artificial and Natural Radionuclide Concentrations of Wheat and Barley Samples in Karbala, Iraq

    Directory of Open Access Journals (Sweden)

    Reza Pourimani

    2018-04-01

     Conclusion: As the findings of the present study indicated, the specific activities of natural radionuclides in the soil were close to that of the world average. The observation of artificial radiocaesium, which is released by nuclear accidents or weapon test, in all soil samples was indicative of the pollution of the studied regions by radioactive dust.

  11. Natural and artificial radionuclides in forest and bog soils: tracers for migration processes and soil development

    International Nuclear Information System (INIS)

    Schleich, N.; Degering, D.; Unterricker, S.

    2000-01-01

    Radionuclide distributions in undisturbed forest and bog soils, mostly situated in Saxony, Germany (Erzgebirge), were studied. Low concentrations of naturally-occurring U and Th decay series nuclides, including 210 Pb, and artificial radioisotopes ( 125 Sb, 134 Cs, 137 Cs, 241 Am) were determined using low-level γ-spectrometry. In addition, the activities of 238 Pu and 239,240 Pu were determined by radiochemical separation and α-spectrometry. 14 C and excess 210 Pb dating methods were used to date the sampled bog profiles. The different radionuclides show characteristic depth distributions in the forest and bog soil horizons, which were sub-sampled as thin slices. 125 Sb, 241 Am, 238 Pu and 239,240 Pu are strongly fixed in soil organic matter. In spruce forest soils, the influence of soil horizons with distinct properties dominates the vertical time-dependent distribution. In ombrotrophic bogs, the peak positions correlated with the year of maximum input of each nuclide. The Sb, Am and Pu ''time markers'' and the 14 C and 210 Pb dating results correspond very well. Although Cs seems to be relatively mobile in organic as well as mineral forest soil horizons, it is enriched in the organic material. In ombrotrophic bogs, Cs is very mobile in the peat deposit. In Sphagnum peat, Cs is translocated continuously towards the growing apices of the Sphagnum mosses, where it is accumulated. (orig.)

  12. Modeling the chemical behavior of radionuclides in severe nuclear accidents

    International Nuclear Information System (INIS)

    Gieseke, J.A.; Alexander, C.A.

    1986-01-01

    The chemical behavior of radionuclides can affect their eventual release to the environment during transport under accident conditions. Four areas or processes of importance are: release from the fuel and core region, reactions with gaseous environments and surfaces in the RCS, core-concrete interactions, and reactions with gases, surfaces and liquids in the containment. In the fuel itself, for example, the chemical potential of oxygen determines which complexes such as Cs 2 UO 4 may be formed in the solid state. Interactions between fission products and various gases, vapors, or surfaces (including deposits) may affect whether significant retention occurs in the RCS. For cases where molten components of the core may fall through to interact with the concrete cavity floor, the chemical composition of the melt and concrete and their chemical interactions are predicted to determine, to a large extent, the rates at which fission products are evolved. Finally, in the containment building atmosphere, the presence of volatile iodine species may result from chemical reactions. Various computer codes are available which provide predictions of chemical behavior in these four areas of importance. The results demonstrate the important role chemistry can have in affecting release of radionuclides to the environment

  13. Tracing Fallout Radionuclide Behavior During Atmospheric Deposition and Pedogenesis

    Science.gov (United States)

    Landis, J. D.

    2017-12-01

    Short-lived fallout radionuclides 7Be (54 day half-life) and 210Pbexcess (22.3 year half-life) inform problems in geomorphology covering timespans of days to decades. Linking these radionuclides together is a powerful strategy, since the ratio 7Be:210Pb can control for changes in the activity of each, provided that the tracers have similar behavior through relevant chemical and physical processes such as interception, sorption, dilution, transport, etc. To investigate the extent to which 7Be and 210Pbxs share a common behavior, I measured these radionuclides in atmospheric deposition, vegetation, and stable soil, sediment and peat profiles. Bulk deposition of 7Be and 210Pb was measured in weekly intervals for 6 years of continuous record. Samples of red oak leaves (Quercus rubra) were collected regularly over 4 years at a site co-located with precipitation collection. Soil pits were sampled by high resolution methods at regional, undisturbed sites. In all samples 7Be, 210Pb, and other nuclides were measured by high-precision gamma spectrometry. Depositional fluxes of 7Be and 210Pb were highly correlated, with 7Be:210Pb converging to the long-term mean activity ratio of ca. 10.5 over intervals of 7 to 14 days. Red oak foliage accumulated 7Be and 210Pb at a linear rate during both growth and senescence, and appeared to maintain a dynamic equilibrium with atmospheric deposition. Canopies of both forest and grass intercepted on the order of 50% of deposition; the remainder reached underlying soil, where 7Be activity showed an exponential decline due to rapid hydrologic penetration of soil surface. Features of 210Pbxs soil profiles, including a subsurface maximum, reflect the same penetration pattern integrated over decades of deposition. Application of the Linked Radionuclide aCcumulation (LRC) model demonstrated that 210Pb moves through soil, peat and fluvial sediment profiles at rates on the order of 1 mm per year, similar to other atmospherically-derived metals

  14. Vibration behavior of the artificial barrier system

    Energy Technology Data Exchange (ETDEWEB)

    Mikoshiba, Tadashi; Ogawa, Nobuyuki; Nakamura, Izuru [National Research Inst. for Earth sceince and Disaster Prevention (Japan)

    2000-02-01

    This study aims at production of a mimic specimen of artificial barrier, experimental elucidation of influence of seismic motion due to a vibration experiment on the artificial barrier system, and establishment of an evaluating method on its long-term behavior. The study has been carried out under a cooperative study of the National Research Institute for Earth Science and Disaster Prevention and the Japan Nuclear Cycle Development Institute. In 1998 fiscal year, an artificial barrier specimen initiated by crosscut road was produced, and their random wave and actual seismic wave vibrations were carried out to acquire their fundamental data. As a result of the both vibrations, it was found that in a Case 2 specimen of which buffer material was swelled by poured water, the material was integrated with a mimic over-pack to vibrate under judgement of eigen-frequency, maximum acceleration ratio, and so forth on the test results. And, in a Case 1 specimen, it was thought that the mimic over-pack showed an extreme non-linear performance (soft spring) because of reducing eigen-frequency with increase of its vibration level. (G.K.)

  15. Comparative analysis of the mobility of uranium and artificial radionuclides in the ecosystem of the Yenisei River

    Energy Technology Data Exchange (ETDEWEB)

    Bolsunovsky, Alexander; Medvedeva, Marina [Institute of Biophysics SB Russian Academy of Sciences, 660036, Krasnoyarsk (Russian Federation)

    2014-07-01

    The Yenisei River is one of the largest rivers in the world, which had been subjected to radioactive contamination for over 50 years, due to operation of the Mining-and-Chemical Combine (MCC) of Rosatom at Zheleznogorsk, which had been producing weapons-grade plutonium. Bottom sediments and flood plain of the Yenisei River are contaminated by artificial radionuclides, including transuranium ones, both close to the MCC and at a considerable distance downstream. The MCC is also a source of uranium isotopes in the Yenisei. Thus, the Yenisei River basin is a unique environment for studying the mobility of both uranium isotopes and artificial radionuclides in all components of the aquatic ecosystem. The purpose of this study was to compare the mobility of uranium and artificial radionuclides in the ecosystem of the Yenisei River. Samples of water, sediments, and aquatic organisms were used as study material. Aquatic organisms were represented by submerged plants, benthic-feeding fish, and zoo-benthos. The submerged plants (macrophytes) analyzed were of five species: Fontinalis antipyretica, Potamogeton lucens, Ceratophyllum demersum, Myriophyllum spicatum, and Elodea canadensis. Grayling (Timalus arcticus) represented benthic-feeding fish, and zoo-benthos species were represented by Philolimnogammarus viridis, which forms the major part of the grayling's diet. Samples were collected at positions in the vicinity of the MCC discharge point, at a distance of 110 km downstream of Krasnoyarsk, and upstream of the MCC, during sampling campaigns in 2008-2012. Radionuclide measurements were performed using a wide range of instrumental methods: gamma-spectrometry with a 'Canberra' spectrometer (U.S.), mass spectrometry with an 'Agilent' spectrometer (U.S.), neutron activation analysis, and beta-alpha radiometry. The results obtained in this study suggest that the part of the Yenisei River ecosystem contaminated due to MCC radioactive discharges contains

  16. The natural and artificial radionuclides in drinking water samples and consequent population doses

    Directory of Open Access Journals (Sweden)

    Aydan Altıkulaç

    2015-10-01

    Full Text Available Concentration levels of 226Ra, 228Ra, 40K and 137Cs were determined in 52 drinking water samples collected from the different supplies in Samsun province to evaluate annual effective dose due to the ingestion of the drinking water samples. The activity concentrations of 226Ra, 228Ra and 40K natural radionuclides in the drinking water samples varied from <27 to 2431 mBq L−1, <36 to 270 mBq L−1 and <47 to 2880 mBq L−1 respectively. The activity concentrations of the artificial radionuclide 137Cs in the drinking water samples were lower than minimum detectable activity except in one drinking water sample (DW14 with an associated activity concentration of 2576 mBq L−1. Contributions of the consumed water samples to annual effective dose from 226Ra, 228Ra and 40K varied from 1.6 to 33.4 μSv y−1 with a mean of 6.1 μSv y−1, 2.2 to 46.8 μSv y−1 with a mean of 8.6 μSv y−1, 4.7 to 97.5 μSv y−1 with a mean of 17.9 μSv y−1 for infants, children and adults, respectively. The results showed that all values of the annual effective dose of ingestion of these water samples were below the individual dose criterion of 100 μSv y−1 reported by World Health Organization (WHO.

  17. Behavior of Chernobyl fallout radionuclides in peat combustion

    International Nuclear Information System (INIS)

    Jantunen, M.J.; Reponen, A.; Mustonen, R.; Itkonen, A.; Kauranen, P.

    1992-01-01

    The fallout from the explosion and fire at the Chernobyl nuclear power plant concentrated levels of up to 10 kBq 137Cs kg-1 dry weight in the fuel peat harvested during the summer of 1986 in Finland. We investigated the behavior of fallout radionuclides 137Cs, 134Cs, 106Ru, 144Ce, 125Sb, 95Zr, and 110mAg together with naturally occurring 210Pb and 226Ra in the combustion of this contaminated peat in four different power plants. The elements antimony, ruthenium, lead, and cesium were enriched on the smallest particles, indicating that they were in a volatile chemical form, while cerium, zirconium, and radium were nonvolatile at the combustion temperatures. This result confirms the previous finding that ruthenium is volatile in combustion. Although metallic ruthenium requires 2,310 degrees C to melt, some of its oxides melt and evaporate at much lower temperatures

  18. Behavior of natural radionuclides in wastewater treatment plants

    International Nuclear Information System (INIS)

    Camacho, A.; Montaña, M.; Vallés, I.; Devesa, R.; Céspedes-Sánchez, R.; Serrano, I.; Blázquez, S.; Barjola, V.

    2012-01-01

    56 samples, including influent, primary effluent, secondary effluent and final effluent wastewater from two Spanish municipal wastewater treatment plants (WWTPs), were analyzed to assess both the occurrence and behavior of natural radioactivity during 12 sampling campaigns carried out over the period 2007–2010. Influent and final effluent wastewaters were sampled by taking into account the hydraulic residence time within the WWTP. A wide range of gross alpha activities (15–129 mBq/L) and gross beta activities (477–983 mBq/L) in liquid samples were obtained. A correlation analysis between radioactivity in liquid samples and the performance characteristics of the WWTPs was performed. The results in liquid samples showed that gross beta activities were not influenced by treatment in the studied WWTPs. However, gross alpha activities behave differently and an increase was detected in the effluent values compared with influent wastewater. This behavior was due to the increase in the total dissolved uranium produced during secondary treatment. The results indicate that the radiological characteristics of the effluents do not present a significant radiological risk and make them suitable for future applications. - Highlights: ► Liquids from WWTPs were analyzed to know the behavior of natural radionuclides. ► Gross beta activities were not influenced by treatment in the studied WWTPs. ► Increase in gross alpha activity was observed due to uranium desorption/solubilisation. ► Correlation between gross alpha activity and the chemical oxygen demand was found

  19. Processes engaged in the persistence in atmosphere of previously deposited artificial radionuclides

    International Nuclear Information System (INIS)

    Piga, Damien

    2010-01-01

    Since 1959, atmospheric sampling stations of the environmental radioactivity permanent observatory measure both natural and artificial radioactivity in ambient air. Nowadays, Cs-137 (30.07 years), an artificial radionuclide mainly issue from atmospheric weapons tests and several accidents, is still measured at trace level in the lower atmosphere although there is no significant release anymore. The aim of this study was to identify and characterize the processes which explain this persistence. Areas highly contaminated by Chernobylsk accident are the major contributors to the Cs-137 atmospheric persistence in France. In these areas, wildfires are the most significant resuspension processes during the dry season and can lead to long range transport events. Around 1013 Bq of Cs-137 are yearly resuspended by this process. In connection with significant increases of total suspended particles, Sahara is the second area involved in the atmospheric Cs-137 persistence due to dust transport events. The whole of these events has a mean contribution of around 1/3 of the Cs-137 background level at the French scale. The last identified process is the wood burning during winter. Even if its emission factor is low, spatial extent of source areas and quantities used at the season scale makes wood burning a significant process compared to ambient trace levels. At the French scale, around 1011 Bq of Cs-137 are yearly resuspended by this process. During this season, the decrease of ventilation conditions in the lower atmosphere leads to an increase of the background level whereas significant increases are due to long range transport events from Eastern Europe

  20. Physico-chemical behavior of radionuclides in fresh water

    International Nuclear Information System (INIS)

    Kimura, Yuichiro; Ogawa, Yoshihiro; Honda, Yoshihide; Katsurayama, Kosuke.

    1980-01-01

    In order to elucidate the physico-chemical behavior of the radionuclides such as 60 Co, 106 Ru and 144 Ce in fresh water, the effects of aging of the radionuclides in fresh water on their physico-chemical states were studied by high-voltage paper electrophoresis, and were also investigated by paper chromatography for nitrosylruthenium complexes. 60 Co showed not only cationic species, but also electroneutral species with aging in fresh water. 106 Ru in the original form of chloro complexes showed relatively a large number of well-defined species, with aging in fresh water, the negatively charged forms decreased slowly with changing of electroneutral forms. 106 Ru in the binuclear complexes of nitrosylruthenium was separated into four anionic, one neutral and one cationic species. The cationic fraction decreased with increasing anionic and with changing neutral. By paper chromatographic separation, about 90% of Ru appeared with Rf 106 Ru in the nitrato complexes was separated into two anionic, one neutral and one cationic species. The cationic fraction decreased with changing both neutral and anionic. More than 95% of Ru appeare with R sub(f) 106 Ru in the nitro complexes was separated into more than several anionic, one neutral and cationic species. The dinitro species with R sub(f) >= 0.8 decreased with increasing mono- and nonnitro species with R sub(f) 144 Ce in the original dilute HCl solution showed initially cationic species. However, the electroneutral species was formed with aging in fresh water. Colloidal or particulate and more or less adsorbable species of 144 Ce were also found. (author)

  1. Artificial radionuclide tracer supply to the Denmark Strait overflow between 1972 and 1981

    Science.gov (United States)

    Livingston, Hugh D.; Swift, James H.; Ostlund, H. Gote

    1985-01-01

    Measurements of the concentrations of the artificial radionuclides 3H, 137Cs, and 90Sr in the northern Irminger Sea in 1972 and 1981 are reported. In both years, tracer measurements from this area included data from samples of the dense overflow water from the north through Denmark Strait. All three tracers were strongly correlated inversely with salinity in the dense outflows—the tracer maxima being related directly to the salinity minimum. When the tracer characteristics in the outflows in 1972 and 1981 were compared, concentrations of all in 1981 were observed to be about double the 1972 values. The individual tracer concentrations—on a decay-corrected, density-normalized basis—were higher in increasing order: 90Sr (+93%) seas of advected European nuclear fuel reprocessing wastes. Both the tracer and hydrographic data are used to identify northern locations of intermediate water formation capable of supplying the observed dense overflow water characteristics. It is argued, from the time taken for the overflow water to reflect the new surface 137Cs source, that transport from the source to the overflow can be quite rapid (about 2 years).

  2. Artificial radionuclide tracer supply to the Denmark strait overflow between 1972 and 1981

    International Nuclear Information System (INIS)

    Livingston, H.D.; Swift, J.H.; Ostlund, H.G.

    1985-01-01

    Measurements of the concentrations of the artificial radionuclides 3 H, 137 Cs, and 90 Sr in the northern Irminger Sea in 1972 and 1981 are reported. In both years, tracer measurements from this area included data from samples of the dense overflow water from the north through Denmark Strait. All three tracers were strongly correlated inversely with salinity in the dense outflows-the tracer maxima being related directly to the salinity minimum. When the tracer characteristics in the outflows in 1972 and 1981 were compared, concentrations of all in 1981 were observed to be about double the 1972 values. The individual tracer concentrations-on a decay-corrected, density-normalized basis-were higher in increasing order: 90 Sr(+93%) 3 H(+115%) 137 Cs(+150%). The relatively greater increases for 3 H and 137 Cs were attributed to contributions of new sources of these tracers in northern surface waters: the 3 H source is argued to derive from atmospheric hydrological recycling, whereas the 137 Cs source is identified as the input to the Greenland and Iceland seas of advected European nuclear fuel reprocessing wastes. Both the tracer and hydrographic data are used to identify northern locations of intermediate water formation capable of supplying the observed dense overflow water characteristics. It is argued, from the time taken for the overflow water to reflect the new surface 137 Cs source, that transport from the source to the overflow can be quite rapid (about 2 years)

  3. Physico-chemical behavior of radionuclides in seawater

    International Nuclear Information System (INIS)

    Kimura, Yuichiro; Ogawa, Yoshihiro; Honda, Yoshihide; Katsurayama, Kosuke.

    1980-01-01

    To elucidate the physico-chemical states of radionuclides in seawater in relation to uptake by the marine biosphere, the physicochemical behavior of radiocobalt, radioruthenium and radiocerium in seawater was investigated by electrodialysis, high-voltage paper electrophoresis, and also by paper chromatography for nitrosylruthenium complexes. Most of the radiocobalt in seawater behaved as dialytic cations. However, these cationic species were not necessarily simple divalent, because their electrophoretic bands were rather diffuse and showed two peaks temporarily. The electroneutral form also increased with aging in seawater. The radioruthenium in seawater showed relatively a number of well-defined species which could be readily classified into anionic, cationic, electroneutral, colloidal or particulate, non-dialytic and more or less adsorbable species. The radioruthenium in the chloro and nitratonitrosylruthenium complexes occurred mainly electroneutral and anionic species, while nitro and binuclear oxygen-bridged nitratonitrosylruthenium complexes showed dominant anionic species. The hydrolysis of higher nitro and nitratonitrosylruthenium complexes to lower ones was demonstrated with aging in seawater by paper chromatography. The radiocerium in seawater showed initially cationic species. However, the electroneutral and anionic species were revealed with aging by electrodialysis. The radiocerium were strongly adsorbed on filter paper at the starting band in paper electrophoresis, presumably because of the formation of strongly adsorbable or insoluble hydrolytic species or particle formation. (author)

  4. Distribution of artificial radionuclides in particle-size fractions of soil on fallout plumes of nuclear explosions.

    Science.gov (United States)

    Kabdyrakova, A M; Lukashenko, S N; Mendubaev, A T; Kunduzbayeva, A Ye; Panitskiy, A V; Larionova, N V

    2018-06-01

    In this paper are analyzed the artificial radionuclide distributions ( 137 Cs, 90 Sr, 241 Am, 239+240 Pu) in particle-size fractions of soils from two radioactive fallout plumes at the Semipalatinsk Test Site. These plumes were generated by a low-yield surface nuclear test and a surface non-nuclear experiment with insignificant nuclear energy release, respectively, and their lengths are approximately 3 and 0,65 km. In contrast with the great majority of similar studies performed in areas affected mainly by global fallout where adsorbing radionuclides such as Pu are mainly associated with the finest soil fractions, in this study it was observed that along both analyzed plumes the highest activity concentrations are concentrated in the coarse soil fractions. At the plume generated by the surface nuclear test, the radionuclides are concentrated mainly in the 1000-500 μm soil fraction (enrichment factor values ranging from 1.2 to 3.8), while at the plume corresponding to the surface non-nuclear test is the 500-250 μm soil fraction the enriched one by technogenic radionuclides (enrichment factor values ranging from 1.1 to 5.1). In addition, the activity concentration distributions among the different soil size fractions are similar for all radionuclides in both plumes. All the obtained data are in agreement with the hypothesis indicating that enrichment observed in the coarse fractions is caused by the presence of radioactive particles resulted from the indicated nuclear tests. Copyright © 2017 Elsevier Ltd. All rights reserved.

  5. Level and regularities of the artificial radionuclides, getting into the crops of rise agrolandscape in the conditions of the river Ili low reaches

    International Nuclear Information System (INIS)

    Otarov, A.

    2008-01-01

    The results of the researches, aiming at the study of regularities typical for the radionuclides getting into the main crops of rice agrolandscape are given. It is determined that the accumulation of the artificial radionuclides by the main types of crops, cultivated in the low reaches of the river Ili depends on their types, morphological and other peculiarities and the properties of the radionuclides themselves. The structure of the general biological removal and its removed part, mainly, depends on the ways of use of the harvest economically-valuable part

  6. Considerations on the transfer of natural and artificial radionuclides from mother to embryo

    International Nuclear Information System (INIS)

    Toader, Maria; Vasilache, R. A.; Toader, Mirela; Scridon, R.

    1998-01-01

    The transfer from mother to embryo is still a matter of high interest for the radiological protection, especially when the natural radioisotopes are involved. The present paper makes a comparison between two situations, the transfer to the embryo when the mother is subjected to recurrent, constant intake of radionuclides (the case of natural radioisotopes) and the case of prolonged, variable intakes of radionuclides (the case of 137 Cs) after Chernobyl). The embryos studied were not older than 11 weeks and were taken from two areas, Bucharest (for the natural radioisotopes 226 Ra and 210 Po and for 137 Cs and 90 Sr) and uranium mining area (only for natural radioisotopes). The monitoring of the environment factors in the uranium mining area has shown that the dietary intake of natural radionuclides had extremely low variations during the interval of study. The variation of 137 Cs dietary intake was quite important during the study and was reported in previous papers. (authors)

  7. Measurement of natural and artificial radionuclide concentrations in meat consumed in Hong Kong

    International Nuclear Information System (INIS)

    Mao, S.Y.; Yu, K.N.

    1995-01-01

    Radionuclides in meat are determined using the EG and G ORTEC photon spectrometer system. Most of the naturally occurring radionuclides are found to have specific activities below the detectable limit. For our samples, 40 K is found to have values ranging from 295-407 Bq/kg, 172-423 Bq/kg and 172-282 Bq/kg for beef, pork and chicken meat samples, respectively, while 137 Cs has values from 0.19-2 Bq/kg, 0.34-0.71 Bq/kg and 0.12-0.53 Bq/kg, respectively. The estimated weighted committed dose equivalent due to the ingestion of natural radionuclides and 137 Cs in meat is 137 Cs in both sexes are less than the level recommended by the International Commission on Radiological Protection. (author)

  8. Intercomparison of sediment sampling devices using artificial radionuclides in Baltic Sea sediments. The MOSSIE Report

    International Nuclear Information System (INIS)

    2000-01-01

    During the last four decades Baltic Sea sediments have been an excellent object for research by radioecologists and other scientists studying sedimentation and other processes in sediments using artificial radionuclides deposited in sediment laminae of the seabed in chronological order. This is due to two major events which have caused significant radioactive fallout in the Baltic Sea region, leaving distinct markers in the corresponding layers of the sediments. One was the global fallout from atmospheric nuclear weapon tests in the late 1950s and early '60s, resulting in clear peaks of longlived radionuclides such as Cs -13 7, Sr -90 and certain transuranic elements (especially Pu -239,240 ) in the sediments. Another was the fallout from the accident at Chernobyl NPP, in the former USSR, in April 1986. Since the first radioactive clouds from Chernobyl travelled north and caused high deposition in the Baltic Sea region, the Baltic was the sea most affected by the accident. The main long-lived constituents in this fallout were Cs -137 and Cs -134 . These radioactive markers have since been utilised, e.g. in dating sediments and determining the sedimentation rate. The sedimentation rate (mm a -1 ) and sediment accumulation rate (g cm -2 a -1 ) vary widely in the Baltic Sea, depending on the area and local environmental factors there. The rates may even be different at sampling points situated very near to each other. A study carried out in 1995-1996 showed that the sedimentation rates varied between 0.2 and 29 mm a -1 at different soft-bottom sampling sites in the Baltic Sea, depending on the sedimentation itself and the method used for calculation. The corresponding accumulation rates of dry matter ranged from 0.006 to 0.90 g cm -2 a -1 . The importance of undisturbed, high-quality samples is especially pronounced in sedimentation rate studies. The loss of soft surface sediments during sampling can significantly affect the results, at least if the calculations are

  9. First artificial radionuclides for Czechoslovakia after World War II. Pt 2

    International Nuclear Information System (INIS)

    Tesinska, Emilie

    2014-01-01

    The paper outlines negotiations on supplies of radionuclides for scientific research and applications in medicine from abroad (the USA, Canada, Great Britain, Sweden, France and the USSR) held by Czechoslovak scientists and public administration (the Ministry of Public Health, Foreign Affairs and Foreign Trade) in 1947 - 1951. Special attention is paid to the complicated and vain debates in the Czechoslovak government (presided by the communist Klement Gottwald) on the offer of radionuclides from the USA for foreign applicants (as declared by US president Truman in September 1947). (orig.)

  10. Remobilisation of artificial radionuclides from the sediment of the Irish Sea

    International Nuclear Information System (INIS)

    Hunt, G.J.; Kershaw, P.J.

    1990-01-01

    The past decade has seen significant decreases in discharges of radioactivity in liquid wastes from the British Nuclear Fuels plc (BNFL) plant at Sellafield. Concentrations of many Sellafield-derived radionuclides in the water of the Irish Sea have decreased as a result. This will result in the return of previously contaminated sediment to the sediment surface and enhanced seawater/pore-water mixing by bio-irrigation, and may be responsible for higher rates of particle exchange across the sediment-seawater interface. In these circumstances, the decrease in seawater concentrations might be expected to be accompanied by the remobilisation of sediment-bound radionuclides into the water column. We have tested this hypothesis in the Sellafield situation in two ways. First, the differences were examined between measured concentrations of radionuclides in sea water and the concentrations which are to be expected on the basis of extrapolation from the conditions of steadier discharge rates experienced in the past. Secondly, modelling studies have shown that migration of radionuclides into the water phase is likely under these conditions. (author)

  11. Studies of radionuclides behavior on heavily contaminated 5-km zone of СhNPP

    Directory of Open Access Journals (Sweden)

    D. M. Bondarkov

    2016-12-01

    Full Text Available Studies of the radionuclides behavior in the soils of “Red Forest” landfill in the nearest 5-km ChNPP zone were carried out during 2014 - 2015. The parameters of vertical migration and halftimes of upper 5-cm soil layer decontamination were obtained. Forms of occurrence of 90Sr and 137Cs, as well as the disperse composition of the Chernobyl origin fuel particles were evaluated. Behavior of radionuclides described in conditions of the convection-diffusion model and the parameters of the model slightly changed over the past decade.

  12. The enrichment behavior of natural radionuclides in pulverized oil shale-fired power plants

    International Nuclear Information System (INIS)

    Vaasma, Taavi; Kiisk, Madis; Meriste, Tõnis; Tkaczyk, Alan Henry

    2014-01-01

    The oil shale industry is the largest producer of NORM (Naturally Occurring Radioactive Material) waste in Estonia. Approximately 11–12 million tons of oil shale containing various amounts of natural radionuclides is burned annually in the Narva oil shale-fired power plants, which accounts for approximately 90% of Estonian electricity production. The radionuclide behavior characteristics change during the fuel combustion process, which redistributes the radionuclides between different ash fractions. Out of 24 operational boilers in the power plants, four use circulating fluidized bed (CFB) technology and twenty use pulverized fuel (PF) technology. Over the past decade, the PF boilers have been renovated, with the main objective to increase the efficiency of the filter systems. Between 2009 and 2012, electrostatic precipitators (ESP) in four PF energy blocks were replaced with novel integrated desulphurization technology (NID) for the efficient removal of fly ash and SO 2 from flue gases. Using gamma spectrometry, activity concentrations and enrichment factors for the 238 U ( 238 U, 226 Ra, 210 Pb) and 232 Th ( 232 Th, 228 Ra) family radionuclides as well as 40 K were measured and analyzed in different PF boiler ash fractions. The radionuclide activity concentrations in the ash samples increased from the furnace toward the back end of the flue gas duct. The highest values in different PF boiler ash fractions were in the last field of the ESP and in the NID ash, where radionuclide enrichment factors were up to 4.2 and 3.3, respectively. The acquired and analyzed data on radionuclide activity concentrations in different PF boiler ashes (operating with an ESP and a NID system) compared to CFB boiler ashes provides an indication that changes in the fuel (oil shale) composition and boiler working parameters, as well as technological enhancements in Estonian oil shale fired power plants, have had a combined effect on the distribution patterns of natural radionuclides in

  13. Artificial environmental radionuclides in Europe and methods of lowering their foodstuff contamination – a review

    Directory of Open Access Journals (Sweden)

    Katarína Beňová

    2016-01-01

    Full Text Available This review discusses the consequences of the food chain contamination with radionuclides, especially focusing on the radiocaesium impact after the Chernobyl nuclear accident. In particular, the 137Cs isotope still represents a risk. Until present it is still detectable in the meat of game animals, especially in wild boar, but also in elk and reindeer. Although the occurrence of highly contaminated foods in most of Europe is currently limited, along the German-Czech border (the Šumava Region the activity concentration of the 137Cs isotope in the meat of wild boar exceeds the acceptable limit several times. Additionally, the article describes simple processing technologies (cooking, pickling etc. that lead to reduction of radionuclides in contaminated food.

  14. Geochemical effects on the behavior of LLW radionuclides in soil/groundwater environments

    Energy Technology Data Exchange (ETDEWEB)

    Krupka, K.M.; Sterne, R.J. [Pacific Northwest Lab., Richland, WA (United States)

    1995-12-31

    Assessing the migration potential of radionuclides leached from low-level radioactive waste (LLW) and decommissioning sites necessitates information on the effects of sorption and precipitation on the concentrations of dissolved radionuclides. Such an assessment requires that the geochemical processes of aqueous speciation, complexation, oxidation/reduction, and ion exchange be taken into account. The Pacific Northwest National Laboratory (PNNL) is providing technical support to the U.S. Nuclear Regulatory Commission (NRC) for defining the solubility and sorption behavior of radionuclides in soil/ground-water environments associated with engineered cementitious LLW disposal systems and decommissioning sites. Geochemical modeling is being used to predict solubility limits for radionuclides under geochemical conditions associated with these environments. The solubility limits are being used as maximum concentration limits in performance assessment calculations describing the release of contaminants from waste sources. Available data were compiled regarding the sorption potential of radionuclides onto {open_quotes}fresh{close_quotes} cement/concrete where the expected pH of the cement pore waters will equal to or exceed 10. Based on information gleaned from the literature, a list of preferred minimum distribution coefficients (Kd`s) was developed for these radionuclides. The K{sub d} values are specific to the chemical environments associated with the evolution of the compositions of cement/concrete pore waters.

  15. Determination of artificial and natural radionuclides and others trace elements in environmental samples form Antarctica

    International Nuclear Information System (INIS)

    Schuch, L.A.; Godoy, J.M.; Nordemann, D.J.R.

    1994-01-01

    The results of the radioactive elements concentrations, determined by gamma spectrometry and the others trace elements determined by neutron activation analysis of several environmental samples (soils, marine sediments, algae mosses and lichens) in Comandante Ferraz Antartica Station are presented. The high concentrations of Cs-137 were found in lichens and mosses samples and the soils and sediments showed concentrations of natural radionuclides. (C.G.C.). 8 refs, 1 fig, 3 tabs

  16. ESTIMATION OF THE POPULATION EXPOSURE DOSES FROM NATURAL AND ARTIFICIAL RADIONUCLIDES DUE TO DRINKING-WATER CONSUMPTION FOR THE INHABITANTS OF DIFFERENT AREAS OF RUSSIAN FEDERATION

    Directory of Open Access Journals (Sweden)

    Ju. N. Goncharova

    2010-01-01

    Full Text Available The report contains data on specific activity values of natural and artificial radionuclides in the water of underground and surface sources in 19 areas of Russian Federation and data on population internal exposure doses from drinking water consumption in these areas.

  17. ALMERA Proficiency Test: Determination of Natural and Artificial Radionuclides in Soil and Water. IAEA-TEL-2011-04

    International Nuclear Information System (INIS)

    2013-01-01

    The Analytical Laboratories for the Measurement of Environmental Radioactivity (ALMERA) network is a cooperative effort of analytical laboratories worldwide. Members of the network are nominated by their respective Member States on the expectation of providing reliable and timely analysis of environmental samples in the event of an accidental or intentional release of radioactivity. The ALMERA network consists of 131 laboratories representing 81 Member States at December 2012. The IAEA's Environment Laboratories in Seibersdorf and Monaco are the central coordinators of the ALMERA network activities. The IAEA helps the ALMERA network to maintain their readiness by coordinating activities, including the organization of meetings, development of standardized methods of sample collection and analysis, and organization of interlaboratory comparison exercises and proficiency tests as tools for external quality control. IAEA proficiency tests and interlaboratory comparison exercises are organized on a regular basis specifically for the members of the ALMERA network. At least one exercise is organized per year by the IAEA for the ALMERA network. These exercises are designed to monitor and to demonstrate the performance and analytical capabilities of the network members, and to identify gaps and problem areas where further development is needed. The ALMERA proficiency tests enable ALMERA members to report their results on gamma emitting radionuclides in a very short time frame, i.e. three days, which is what would be required for emergency response. This publication presents the results of the ALMERA proficiency test IAEA-TEL-2011-04 on the determination of natural and artificial radionuclides in water and soil. The methodologies, data evaluation approach, summary evaluation of each radionuclide and individual evaluation reports for each laboratory are also described

  18. Radionuclide behavior in water saturated porous media: Diffusion and infiltration coupling of thermodynamically and kinetically controlled radionuclide water - mineral interactions

    International Nuclear Information System (INIS)

    Spasennykh, M.Yu.; Apps, J.A.

    1995-05-01

    A model is developed describing one dimensional radionuclide transport in porous media coupled with locally reversible radionuclide water-mineral exchange reactions and radioactive decay. Problems are considered in which radionuclide transport by diffusion and infiltration processes occur in cases where radionuclide water-solid interaction are kinetically and thermodynamically controlled. The limits of Sr-90 and Cs-137 migration are calculated over a wide range of the problem variables (infiltration velocity, distribution coefficients, and rate constants of water-mineral radionuclide exchange reactions)

  19. Artificial radionuclides in oils from the underground nuclear test site (Perm region, Russia)

    International Nuclear Information System (INIS)

    Kalmykov, S.N.; Sapozhnikov, Yu.A.; Goloubov, B.N.

    1998-01-01

    Underground nuclear tests (UNT) are one of the possible sources of radioactive contamination of environment. About 2500 UNTs were carried out both for military and industrial (peaceful) purposes. In the former Soviet Union most of peaceful UNTs were oriented to the needs of the gas- and oil-extracting industry. Earlier it was considered that the holes of UNT are hermetic and the leakage of radionuclides is negligible. In this work nine oil samples from Gezh oil deposit in Perm region of Russia collected from different holes both where the explosion took part and from distant holes were analyzed for 3 H and 14 C and such fission products as 90 Sr and 134,137 Cs. For the determination of gamma-emitting radionuclides the gamma spectrometry with HPGe detector was used. For 90 Sr determination the measurements of Cherenkov radiation generated by daughter 90 Y were carried out with liquid scintillation equipment. It showed that even in the oil samples from the hole where the explosion took place no measurable 134,137 Cs and 90 Sr activities were detected. For 3 H and 14 C determination the oil samples were fractionated by distillation. For each sample 10-12 fractions were taken. Liquid scintillation spectrometry was used for 3 H and 14 C simultaneous determination. It was shown that in all samples the 3 H and 14 C concentrations are higher than the background level and for the hole where the explosion took place reached the value of about 1.3 x 10 5 Bq/L for low boiling fraction (40-750C). The 3 H and 14 C enrichment of oils from distant holes shows that UNT cavities are not hermetic and the radionuclide migration is not negligible. (author)

  20. Determination of the radioactivity of the artificial 137Cs radionuclide in the Tatra Mountains

    International Nuclear Information System (INIS)

    Kubica, B.; Skiba, S.; Golas, J.; Stobinski, M.; Drewnik, M.; Tuteja-Krysa, M.; Misiak, R.

    2006-01-01

    Sixty samples were collected in different regions of the Tatra Mountains (Poland). It has been found that 137 Cs and 40 K content in the samples strongly depends on the content of the organic matter in the soil and height of the region of the sample collection. Potassium content in the the blueberries and in the moss strongly influences the bioaccumulation of the 137 Cs radionuclide by these plants. Map of the 137 Cs concentration in the polish part of the Tatra Mountains is presented

  1. Integrated performance assessment model for waste policy package behavior and radionuclide release

    International Nuclear Information System (INIS)

    Kossik, R.; Miller, I.; Cunnane, M.

    1992-01-01

    Golder Associates Inc. (GAI) has developed a probabilistic total system performance assessment and strategy evaluation model (RIP) which can be applied in an iterative manner to evaluate repository site suitability and guide site characterization. This paper describes one component of the RIP software, the waste package behavior and radionuclide release model. The waste package component model considers waste package failure by various modes, matrix alteration/dissolution, and radionuclide mass transfer. Model parameters can be described as functions of local environmental conditions. The waste package component model is coupled to component models for far-field radionuclide transport and disruptive events. The model has recently been applied to the proposed repository at Yucca Mountain

  2. Integrated performance assessment model for waste package behavior and radionuclide release

    International Nuclear Information System (INIS)

    Kossik, R.; Miller, I.; Cunnane, M.

    1992-01-01

    Golder Associates Inc. (GAI) has developed a probabilistic total system performance assessment and strategy evaluation model (RIP) which can be applied in an iterative manner to evaluate repository site suitability and guide site characterization. This paper describes one component of the RIP software, the waste package behavior and radionuclide release model. The waste package component model considers waste package failure by various modes, matrix alteration/dissolution, and radionuclide mass transfer. Model parameters can be described as functions of local environmental conditions. The waste package component model is coupled to component models for far-field radionuclide transport and disruptive events. The model has recently been applied to the proposed repository at Yucca Mountain

  3. Geochemical behavior of radionuclides and heavy metals in soils from Corumbatai River basin (SP), Brazil

    International Nuclear Information System (INIS)

    Conceicao, Fabiano Tomazini da

    2004-01-01

    The purpose of this research was to study the geochemical behavior of radionuclides and heavy metals in soils of agricultural use at Corumbatai River basin (SP). The natural concentration and variability in sedimentary rocks at Corumbatai river basin follow the trend Ca > Mg > K > Na, with the concentration of heavy metals and radionuclides. The distribution of exposure rate in soils shows the occurrence of higher values towards south of the Corumbatai river basin, region where are applied phosphate fertilizers, amendments and 'vinhaca' in sugar cane crops. Heavy metals and radionuclides incorporated in phosphate fertilizers and amendments are annually added during the fertilization process in the sugar cane crops, but if they are utilized in accordance with the recommended rate, they do not rise the concentration levels in soils up to hazards levels. Thus, they are lower transferred from soils to sugar cane at Corumbatai river basin, not offering hazard to the ecosystem and animal or human health. (author)

  4. Radionuclide distributions and sorption behavior in the Susquehanna--Chesapeake Bay System

    Energy Technology Data Exchange (ETDEWEB)

    Olsen, C.R.; Larsen, I.L.; Lowry, P.D.; McLean, R.I.; Domotor, S.L.

    1989-01-01

    Radionuclides released into the Susquehanna--Chesapeake System from the Three Mile Island, Peach Bottom, and Calvert Cliffs nuclear power plants are partitioned among dissolved, particulate, and biological phases and may thus exist in a number of physical and chemical forms. In this project, we have measured the dissolved and particulate distributions of fallout /sup 137/Cs; reactor-released /sup 137/Cs, /sup 134/Cs, /sup 65/Zn, /sup 60/Co, and /sup 58/Co; and naturally occurring /sup 7/Be and /sup 210/Pb in the lower Susquehanna River and Upper Chesapeake Bay. In addition, we chemically leached suspended particles and bottom sediments in the laboratory to determine radionuclide partitioning among different particulate-sorbing phases to complement the site-specific field data. This information has been used to document the important geochemical processes that affect the transport, sorption, distribution, and fate of reactor-released radionuclides (and by analogy, other trace contaminants) in this river-estuarine system. Knowledge of the mechanisms, kinetic factors, and processes that affect radionuclide distributions is crucial for predicting their biological availability, toxicity, chemical behavior, physical transport, and accumulation in aquatic systems. The results from this project provide the information necessary for developing accurate radionuclide-transport and biological-uptake models. 76 refs., 12 figs.

  5. Artificial intelligence: Collective behaviors of synthetic micromachines

    Science.gov (United States)

    Duan, Wentao

    Synthetic nano- and micromotors function through the conversion of chemical free energy or forms of energy into mechanical motion. Ever since the first reports, such motors have been the subject of growing interest. In addition to motility in response to gradients, these motors interact with each other, resulting in emergent collective behavior like schooling, exclusion, and predator-prey. However, most of these systems only exhibit a single type of collective behavior in response to a certain stimuli. The research projects in the disseratation aim at designing synthetic micromotors that can exhibit transition between various collective behaviors in response to different stimuli, as well as quantitative understanding on the pairwise interaction and propulsion mechanism of such motors. Chapter 1 offers an overview on development of synthetic micromachines. Interactions and collective behaviors of micromotors are also summarized and included. Chapter 2 presents a silver orthophosphate microparticle system that exhibits collective behaviors. Transition between two collective patterns, clustering and dispersion, can be triggered by shift in chemical equilibrium upon the addition or removal of ammonia, in response to UV light, or under two orthogonal stimuli (UV and acoustic field) and powering mechanisms. The transitions can be explained by the self-diffusiophoresis mechanism resulting from either ionic or neutral solute gradients. Potential applications of the reported system in logic gates, microscale pumping, and hierarchical assembly have been demonstrated. Chapter 3 introduces a self-powered oscillatory micromotor system in which active colloids form clusters whose size changes periodically. The system consists of an aqueous suspension of silver orthophosphate particles under UV radiation, in the presence of a mixture of glucose and hydrogen peroxide. The colloid particles first attract with each other to form clusters. After a lag time of around 5min, chemical

  6. The present-day level of long-living artificial radionuclides content in mosses, lichens and needles of Siberia areas

    International Nuclear Information System (INIS)

    Strakhovenko, V.D.; Sukhorukov, F.V.; Shcherbov, B.L.

    2005-01-01

    The purpose of the paper is to estimate the present-day level of long-living artificial radionuclides activity in lichen-moss cover and needles in the Siberia region. During the expeditionary activities (1995-2004) the Lichen cover mosses and needles were sampled in the Ust'-Ordinsky and Aginsky Buryatsky autonomous regions, Altai area, Republic of Altai, Novosibirsk Region, the Yamal-Nenets Autonomous region. The identical species of lichen, mosses. needles were collected from Siberia (lichens - Cladonia, Evernia, Usnea, Parmeli; mosses - Polytrichum, Hylocomium, Pleurozium, Sphagnum; needles - Pinaceae). It was collected 6 and more lichen species from each of 18 sample sites, more than 3 Moss species from 7 sample sites, and in place of coniferous trees joint growth (a pine, a cedar, a fir, a fur-tree and a larch). The needles were selected from all trees and thus were divided into one-year-old and many-year old. The samples were analyzed in the Laboratory of Trace Elements Geochemistry and Ecogeochemistry of the UIGGM, Novosibirsk, using special sample preparation and analysis techniques. The content of 137 Cs were determined by gamma-spectrometry (analyst Stepin A.S.), 90 Sr by beta-radiometry with a radiochemical sample preparation (analyst Makeover I.V.). The data reported are evidence that a present-day level of radioactive contamination in moss-lichen cover and needles of Siberia areas corresponds to this of global background, expect for northern area of Siberia (YNAD) for which hyperactivity are determined for the each of three components. Radiocesium concentration in one-year old needles reflects a level of atmospheric intake only for accidents, for other cases the condition of current needles reflects basically radionuclide level established as the result of dynamic balance between root intake and annual biogenic abscission of needles. (author)

  7. Natural and artificial (90Sr radionuclides in some carbonated mineral waters used in Serbia

    Directory of Open Access Journals (Sweden)

    Janković Marija M.

    2013-01-01

    Full Text Available A radiological characterization of 7 different carbonated mineral water samples collected in the local supermarkets in the area of Belgrade (produced in Serbia was carried out. Analysis included determination of gross alpha and gross beta activities. The obtained results showed that the natural activity concentrations of alpha and beta emitting radionuclides in carbonated mineral water samples were within World Health Organization recommended levels, except for the Heba Strong and Kiseljak samples where the beta activity exceeds 1 Bq/L. For these two water samples gamma spectrometry analysis was performed as well as determination of 90Sr by oxalic method. The instrumentation used to count the gross alpha and gross beta activities, as well as for 90Sr, was a/b low level proportional counter Thermo Eberline FHT 770 T. Gamma spectrometric measurements were performed using a HPGe Canberra detector with a counting efficiency of 20%. The annual effective dose equivalent due to ingestion of investigated waters was calculated for age group >17, and obtained values are lower than 0.1 mSv recommended reference level. Finally, a comparison of the investigated waters with worldwide data was made. [Projekat Ministarstva nauke Republike Srbije, br. III43009

  8. A Preliminary Study of Two Different Clays for Separation of Some Artificial Radionuclides in Stimulated Waste

    International Nuclear Information System (INIS)

    Lasheen, Y.F.; Seliman, A.F.; Shehata, F.A.; Youssef, M.A.; Abo-Aly, M.

    2016-01-01

    The removal of long lived radionuclides, such as 134 Cs(I), 133 Ba(II), 90 Sr(II) and 152 Eu(III) by bentonite (W-Bent) and kaolin (S-Kaol) was studied as a function of different parameters using a batch technique. The results showed that the optimum ph was selected to be 6. Kinetically in case of W-Bent, the adsorption is heterogeneous for 134 Cs, 133 Ba and homogenous for 90 Sr and 152 Eu. The distribution coefficient values follow the order of 1 '5 2 Eu> 134 Cs> 90 Sr> 133 Ba. Langmuir, Freundlish, Dubinin-Raduskevich (D-R) and Temkin isotherm models were applied. According to the D-R model, W-Bent showed a high affinity to 152 Eu with a maximum capacity (q m = 0.43 mol/Kg) in comparison with S-Kaol (q m =0.023 mol/Kg). Also according to D-R model the adsorption energy (E> 8.0 KJ mol -1 ) that means the adsorption reaction is expected to be chemisorption. Finally both clays are cost-effective sorbent materials with an excellent adsorption capacity, but some surface modification for S-Kaol is recommended to be more effective than its natural form

  9. Determination of the concentration of natural and artificial radionuclides in the soil of the Campus of the Federal University of Sergipe, Brazil

    International Nuclear Information System (INIS)

    Cardoso, L.X.; Souza, S.O.; Ferreira, F.C.L.; Ferreira, O.C.; Barboza, E.

    2011-01-01

    Natural radionuclides are not only found scattered in the earth's crust but in all environments on the planet: soil, water and atmosphere, and leading from the natural radioactive series of 238 U and 232 Th, and the 40 K. However, the artificial radionuclides in the vast majority produced since the 40 decade and released into the environment by nuclear tests, were spread throughout the globe by the process known as 'fallout'. In view of the lack of geochemical data in the state of Sergipe, this work was done in order to analyze the activity of radionuclides in the soil of the Federal University of Sergipe, located at the city of Sao Cristovao. The collection of samples was performed at five points on the campus of the university, which were sent to the Eletronuclear Environmental Monitoring Laboratory, located in Paraty - RJ, and analyzed by gamma spectrometry, thereby obtaining the radioactive elements present in samples. (author)

  10. Recent developments in assessment of long-term radionuclide behavior in the geosphere-biosphere subsystem.

    Science.gov (United States)

    Smith, G M; Smith, K L; Kowe, R; Pérez-Sánchez, D; Thorne, M; Thiry, Y; Read, D; Molinero, J

    2014-05-01

    Decisions on permitting, controlling and monitoring releases of radioactivity into the environment rely on a great variety of factors. Important among these is the prospective assessment of radionuclide behavior in the environment, including migration and accumulation among and within specific environmental media, and the resulting environmental and human health impacts. Models and techniques to undertake such assessments have been developed over several decades based on knowledge of the ecosystems involved, as well as monitoring of previous radionuclide releases to the environment, laboratory experiments and other related research. This paper presents developments in the assessment of radiation doses and related research for some of the key radionuclides identified as of potential significance in the context of releases to the biosphere from disposal facilities for solid radioactive waste. Since releases to the biosphere from disposal facilities involve transfers from the geosphere to the biosphere, an important aspect is the combined effects of surface hydrology, near-surface hydrogeology and chemical gradients on speciation and radionuclide mobility in the zone in which the geosphere and biosphere overlap (herein described as the geosphere-biosphere subsystem). In turn, these aspects of the environment can be modified as a result of environmental change over the thousands of years that have to be considered in radioactive waste disposal safety assessments. Building on the experience from improved understanding of the behavior of the key radionuclides, this paper proceeds to describe development of a generic methodology for representing the processes and environmental changes that are characteristic of the interface between the geosphere and the biosphere. The information that is provided and the methodology that is described are based on international collaborative work implemented through the BIOPROTA forum, www.bioprota.org. Copyright © 2013 Elsevier Ltd. All

  11. VICTORIA: A mechanistic model of radionuclide behavior in the reactor coolant system under severe accident conditions

    International Nuclear Information System (INIS)

    Heams, T.J.; Williams, D.A.; Johns, N.A.; Mason, A.; Bixler, N.E.; Grimley, A.J.; Wheatley, C.J.; Dickson, L.W.; Osborn-Lee, I.; Domagala, P.; Zawadzki, S.; Rest, J.; Alexander, C.A.; Lee, R.Y.

    1992-12-01

    The VICTORIA model of radionuclide behavior in the reactor coolant system (RCS) of a light water reactor during a severe accident is described. It has been developed by the USNRC to define the radionuclide phenomena and processes that must be considered in systems-level models used for integrated analyses of severe accident source terms. The VICTORIA code, based upon this model, predicts fission product release from the fuel, chemical reactions involving fission products, vapor and aerosol behavior, and fission product decay heating. Also included is a detailed description of how the model is implemented in VICTORIA, the numerical algorithms used, and the correlations and thermochemical data necessary for determining a solution. A description of the code structure, input and output, and a sample problem are provided

  12. Transfer of some artificial (226Sr and 137Cs) and natural (40K and 226Ra) radionuclides from milk to its products

    International Nuclear Information System (INIS)

    Al-Masri, M. S.; Nashawati, A.; Amin, Y.; Al-Akel, B.

    2005-01-01

    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)

  13. 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)

  14. Recent developments in assessment of long-term radionuclide behavior in the geosphere-biosphere subsystem

    International Nuclear Information System (INIS)

    Smith, G.M.; Smith, K.L.; Kowe, R.; Pérez-Sánchez, D.; Thorne, M.; Thiry, Y.; Read, D.; Molinero, J.

    2014-01-01

    Decisions on permitting, controlling and monitoring releases of radioactivity into the environment rely on a great variety of factors. Important among these is the prospective assessment of radionuclide behavior in the environment, including migration and accumulation among and within specific environmental media, and the resulting environmental and human health impacts. Models and techniques to undertake such assessments have been developed over several decades based on knowledge of the ecosystems involved, as well as monitoring of previous radionuclide releases to the environment, laboratory experiments and other related research. This paper presents developments in the assessment of radiation doses and related research for some of the key radionuclides identified as of potential significance in the context of releases to the biosphere from disposal facilities for solid radioactive waste. Since releases to the biosphere from disposal facilities involve transfers from the geosphere to the biosphere, an important aspect is the combined effects of surface hydrology, near-surface hydrogeology and chemical gradients on speciation and radionuclide mobility in the zone in which the geosphere and biosphere overlap (herein described as the geosphere-biosphere subsystem). In turn, these aspects of the environment can be modified as a result of environmental change over the thousands of years that have to be considered in radioactive waste disposal safety assessments. Building on the experience from improved understanding of the behavior of the key radionuclides, this paper proceeds to describe development of a generic methodology for representing the processes and environmental changes that are characteristic of the interface between the geosphere and the biosphere. The information that is provided and the methodology that is described are based on international collaborative work implemented through the BIOPROTA forum, (www.bioprota.org). - Highlights: • Geological

  15. State of radionuclides in seawater. Comparison of natural stable and artificial radioactive isotope s of mercury and zinc in natural waters of the arid zone of the USSR

    International Nuclear Information System (INIS)

    Rakhmatov, U; Khikmatov, K; Kist, A.A.; Kulmatov, R.A.; Teshabaev, S.T.; Volkov, A.A.

    1986-01-01

    This paper studies the state of stable and artificial radioactive isotopes of merury and zinc in natural waters of the arid zone of the USSR by radioactivity and radiochemical methods. Convergent results have been obtained for the dissolved forms of mercury and zinc in natural waters of the arid zone in a comparison of the results of radioactivation analysis and laboratory simulation using the radionuclides mercury-203 and zinc-65

  16. Chemical behavior of long-lived radionuclides in the marine environment

    International Nuclear Information System (INIS)

    Edgington, D.N.; Nelson, D.M.

    1983-01-01

    Measurements of long-lived radionuclides in the marine environment have provided a wealth of information regarding the physical, biological, and chemical processes which control the behavior of these and many other pollutants in the oceans. Their value as tracers for the dispersion, transport, and fate of pollutants in the oceans is largely dependent on the chemical properties of each individual radioelement. Differences in these properties, particularly in relation to their interaction with biotic or abiotic particulate matter, result in the separation of parent-daughter radioisotopes in the natural radioelement series or in changes in the ratios of fission and activation products. Such differences have provided the means to provide time scales for a variey of transport processes and to determine sedimentation rates. The properties of these radionuclides in the oceans can, in general, be predicted from the chemical properties of the stable elements. For those elements such as plutonium, for which there are no naturally-occurring stable isotopes, studies of their distribution in the oceans have provided a new important understanding of their chemical behavior. This behavior has not always agreed with what would have been predicted from laboratory studies carried out at far higher concentrations. Differences between observed distributions and laboratory predictions have highlighted the importance of correct experimental conditions in order to avoid confusing experimental artifacts. The interaction of radionuclides with particles in the oceans and marine sediments can be described in terms of simple ion exchange or adsorption equilibria

  17. Comparison of the analytical methods used to determine natural and artificial radionuclides from environmental samples by gamma, alpha and beta spectrometry

    DEFF Research Database (Denmark)

    Pöllänen, Roy; Virtanen, Sinikka; Kämäräinen, Meerit

    In CAMNAR, an extensive interlaboratory exercise on the analytical methods used to determine several radionuclides present in the environmental samples was organized. Activity concentration of different natural radionuclides, such as Rn-222, Pb-210, Po-210, K-40, Ra-226, Ra-228 and isotopes of ur...... Nordic and European countries participated in the intercomparison. Extraordinary variation between the results reported by different laboratories were revealed for some radionuclides indicating the need of future intercomparisons especially in the case of natural water samples.......In CAMNAR, an extensive interlaboratory exercise on the analytical methods used to determine several radionuclides present in the environmental samples was organized. Activity concentration of different natural radionuclides, such as Rn-222, Pb-210, Po-210, K-40, Ra-226, Ra-228 and isotopes...... of uranium, in addition to artificial Cs-137 and Am-241 were analysed from lake sediment samples and drinking water. The measurement techniques were gamma-ray spectrometry, alpha spectrometry, liquid scintillation counting and inductively coupled plasma mass spectrometry. Twenty six laboratories from nine...

  18. Adsorption behavior of radionuclide in water containing sea salts

    International Nuclear Information System (INIS)

    Kani, Yuko; Kamoshida, Mamoru; Asano, Takashi; Tamata, Shin

    2012-01-01

    Waste water caused by the Fukushima Dai-ichi Nuclear Reactor accident contains high level radioactive material with impurities of sea water origin, such as chloride, sodium and magnesium. These impurities have the potential to inhibit the adsorption reaction of radioactive cesium and strontium to adsorbents. We have studied adsorption behavior of radioactive cesium and strontium to adsorbents to measure distribution coefficients (Kd) in the condition of different sea water concentrations. For cesium adsorption, the dependence of Kd on the sea water concentration was affected by the adsorption mechanism of adsorbent; the adsorbents which adsorbed cesium by intercalation showed less dependence of Kd on the sea water concentration, while those adsorbed cesium by ion exchange had smaller Kd with increasing the sea water concentration. For strontium adsorption, Kd decreased as the sea water concentration increased for both adsorbents which adsorbed strontium by intercalation and by ion exchange. The inhibition of intercalation and ion exchange reaction of strontium by calcium ion, that exists high concentration in sea water (400 ppm) and similar hydrated ionic radius with strontium, will cause the decrease of Kd for strontium in the sea water with higher concentration. (author)

  19. Corrosion Behavior of Titanium in Artificial Saliva by Lactic Acid

    Directory of Open Access Journals (Sweden)

    Qing Qu

    2014-07-01

    Full Text Available As one of the main products produced by oral microorganisms, the role of lactic acid in the corrosion of titanium is very important. In this study, the corrosion behavior of titanium in artificial saliva with and without lactic acid were investigated by open-circuit potentials (OCPs, polarization curves and electrochemical impedance spectroscopy (EIS. OCP firstly increased with the amount of lactic acid from 0 to 3.2 g/L and then tended to decrease from 3.2 to 5.0 g/L. The corrosion of titanium was distinctly affected by lactic acid, and the corrosion rate increased with increasing the amount of lactic acid. At each concentration of lactic acid, the corrosion rate clearly increased with increasing the immersing time. Results of scanning electron microscopy (SEM also indicated that lactic acid accelerated the pitting corrosion in artificial saliva. A probable mechanism was also proposed to explain the experimental results.

  20. Migration behavior of radionuclides (60Co, 85Sr and 137Cs) in aerated sandy soil layer

    International Nuclear Information System (INIS)

    Ohtsuka, Yoshiro; Takebe, Shinichi

    1990-01-01

    Differences of the migration behavior and desorption process for radionuclides ( 60 Co, 85 Sr and 137 Cs) in aerated sandy soil layer were studied by sprinkle of distilled water into the contaminated soil with above nuclides in column. Influence of difference desorption process on radionuclide migration was examined by changing the volume of distilled water sprinkled like rain on the contaminated soil. Quantity of sprinkled water affected the concentration distribution of each radionuclide in soil layer. Each nuclide migrated deeper in the layer according to the increase of water amount, and especially, migration behavior of 85 Sr was remarkably influenced by water amount. It is observed that as to 85 Sr maximum contamination part in soil layer moved to deeper layer with increase of water amount, and that, as to 60 Co and 137 Cs, it moved almost never. On the other hand, activity concentration of 60 Co or 137 Cs in effluent was rather high (10 -6 μCi/ml) compared with that of 85 Sr, which could not be detected therein. (author)

  1. Tracing the origin of suspended sediment in a large Mediterranean river by combining continuous river monitoring and measurement of artificial and natural radionuclides

    Energy Technology Data Exchange (ETDEWEB)

    Zebracki, Mathilde, E-mail: zebracki@free.fr [Laboratoire d' Etudes Radioécologiques en milieu Continental et Marin (LERCM), Institut de Radioprotection et de Sûreté Nucléaire (IRSN), Saint-Paul-lez-Durance (France); Eyrolle-Boyer, Frédérique [Laboratoire d' Etudes Radioécologiques en milieu Continental et Marin (LERCM), Institut de Radioprotection et de Sûreté Nucléaire (IRSN), Saint-Paul-lez-Durance (France); Evrard, Olivier [Laboratoire des Sciences du Climat et de l' Environnement (LSCE/IPSL), Unité Mixte de Recherche 8212 (CEA/CNRS/UVSQ), Gif-sur-Yvette (France); Claval, David [Laboratoire d' Etudes Radioécologiques en milieu Continental et Marin (LERCM), Institut de Radioprotection et de Sûreté Nucléaire (IRSN), Saint-Paul-lez-Durance (France); Mourier, Brice [Université Lyon 1, UMR 5023 Ecologie des Hydrosystèmes Naturels et Anthropisés, ENTPE, CNRS, 3, Rue Maurice Audin, F-69518 Vaulx-en-Velin (France); Université de Limoges, GRESE, EA 4330, 123 avenue Albert Thomas, 87060 Limoges (France); Gairoard, Stéphanie [Centre de Recherche et d' Enseignement de Géosciences de l' Environnement (CEREGE), Unité Mixte 34 (AMU/CNRS/IRD), Aix-en-Provence (France); and others

    2015-01-01

    Delivery of suspended sediment from large rivers to marine environments has important environmental impacts on coastal zones. In France, the Rhone River (catchment area of 98,000 km{sup 2}) is by far the main supplier of sediment to the Mediterranean Sea and its annual solid discharge is largely controlled by flood events. This study investigates the relevance of alternative and original fingerprinting techniques based on the relative abundances of a series of radionuclides measured routinely at the Rhone River outlet to quantify the relative contribution of sediment supplied by the main tributaries during floods. Floods were classified according to the relative contribution of the main subcatchments (i.e., Oceanic, Cevenol, extensive Mediterranean and generalised). Between 2000 and 2012, 221 samples of suspended sediment were collected at the outlet and were shown to be representative of all flood types that occurred during the last decade. Three geogenic radionuclides (i.e., {sup 238}U, {sup 232}Th and {sup 40}K) were used as fingerprints in a multivariate mixing model in order to estimate the relative contribution of the main subcatchment sources—characterised by different lithologies—in sediment samples collected at the outlet. Results showed that total sediment supply originating from Pre-Alpine, Upstream, and Cevenol sources amounted to 10, 7 and 2.10{sup 6} tons, respectively. These results highlight the role of Pre-Alpine tributaries as the main sediment supplier (53%) to the Rhone River during floods. Other fingerprinting approaches based on artificial radionuclide activity ratios (i.e., {sup 137}Cs/{sup 239+240}Pu and {sup 238}Pu/{sup 239+240}Pu) were tested and provided a way to quantify sediment remobilisation or the relative contributions of the southern tributaries. In the future, fingerprinting methods based on natural radionuclides should be further applied to catchments with heterogeneous lithologies. Methods based on artificial radionuclides

  2. Radiochemical and radioecological studies of natural and artificial alpha-emitting radionuclides

    International Nuclear Information System (INIS)

    Holm, E.; Persson, B.

    1980-01-01

    Transuranium elements, including uranium and thorium, were analyzed in both marine and terrestrial samples. Vertical profiles of 239+240 Pu, 241 Am, 230 Th, and 238 U, in the Pacific, the Mediterranean, and the Atlantic, measured by different investigators, were compared. Uptake of the fallout isotopes 241 Pu, 240+239 Pu, 238 Pu, and 241 Am in the lichen - reindeer food chain was studied. Americium and thorium exhibited similar biophysical behavior in the environment and in the water column, although the settling velocity for thorium was somewhat higher. Plutonium showed similar distribution in the water columns in different waters. The fraction of ingested plutonium which was retained in the body of reindeer was in good agreement with the value of 3 x 10 -5 predicted for man. Uranium showed a constant concentration in the water column, with a low affinity to particles in the water. The high concentration of uranium in reindeer tissues depended on high intake from drinking water and foodstuffs other than lichens

  3. Study of migration behavior of technogenic radionuclides in the Yenisey River-Kara Sea aquatic system

    International Nuclear Information System (INIS)

    Kuznetsov, Yu.; Legin, E.; Legin, V.; Shishlov, A.; Savitskii, Yu.; Novikov, A.; Goryachenkova, T.

    2001-01-01

    migrates as soluble species weakly sorbed by the solid phase, causing the observed low content of Sr-90 in flood-land deposits and bottom sediments of the Yenisey River. The indicated migration behavior of radionuclides is characteristic of the Yenisey Gulf and the adjacent part of the Kara Sea also. We made similar conclusions when studying the migration behavior of Cs-137, Pu-239,240, and Sr-90 in the Kiev reservoir (1987). The formation of radioactive flood-land deposits is provided by rapid deposition of suspended material in stagnant zones during periodical flood. Humus compounds contribute significantly to accumulation of radionuclides in the flood-land deposits and bottom sediments, which is supported by the observed correlation between the radionuclide (Pu, Am, Eu) and total organic carbon distributions in them. Radiochemical analysis of separate fractions showed that about 20% of Pu and Am are associated with the organic fraction: Pu is nearly equally distributed between humic and fulvic acid fractions, whereas Am is preferentially associated with the fulvic acid fraction (the most mobile fraction of humus matter). It was demonstrated in model experiments that the calcium-hydrocarbonate type of water of the Yenisey River causes suppression of formation of mobile fulvate complexes of hydrolyzable radionuclides and, therefore, their transfer into the aqueous phase. In combination with the observed very high distribution coefficients of the radionuclides and low content of their mobile geochemical forms in flood-land deposits of the Yenisey River this suggest that they cannot contribute somewhat significantly to the secondary radioactive contamination of the river water by all mechanisms except migration by mechanical transfer. (author)

  4. Study of migration behavior of technogenic radionuclides in the Yenisey River-Kara Sea aquatic system

    Energy Technology Data Exchange (ETDEWEB)

    Kuznetsov, Yu.; Legin, E.; Legin, V. [Khlopin Radium Institute, St. Petersburg (Russian Federation); Shishlov, A.; Savitskii, Yu. [Krasnoyarsk Mining and Chemical Combine, Krasnoyarsk (Russian Federation); Novikov, A.; Goryachenkova, T. [Russian Academy of Sciences, Institute of Geochemistry and Analytical Chemistry, Moscow (Russian Federation)

    2001-03-01

    migrates as soluble species weakly sorbed by the solid phase, causing the observed low content of Sr-90 in flood-land deposits and bottom sediments of the Yenisey River. The indicated migration behavior of radionuclides is characteristic of the Yenisey Gulf and the adjacent part of the Kara Sea also. We made similar conclusions when studying the migration behavior of Cs-137, Pu-239,240, and Sr-90 in the Kiev reservoir (1987). The formation of radioactive flood-land deposits is provided by rapid deposition of suspended material in stagnant zones during periodical flood. Humus compounds contribute significantly to accumulation of radionuclides in the flood-land deposits and bottom sediments, which is supported by the observed correlation between the radionuclide (Pu, Am, Eu) and total organic carbon distributions in them. Radiochemical analysis of separate fractions showed that about 20% of Pu and Am are associated with the organic fraction: Pu is nearly equally distributed between humic and fulvic acid fractions, whereas Am is preferentially associated with the fulvic acid fraction (the most mobile fraction of humus matter). It was demonstrated in model experiments that the calcium-hydrocarbonate type of water of the Yenisey River causes suppression of formation of mobile fulvate complexes of hydrolyzable radionuclides and, therefore, their transfer into the aqueous phase. In combination with the observed very high distribution coefficients of the radionuclides and low content of their mobile geochemical forms in flood-land deposits of the Yenisey River this suggest that they cannot contribute somewhat significantly to the secondary radioactive contamination of the river water by all mechanisms except migration by mechanical transfer. (author)

  5. Empirical modeling of dynamic behaviors of pneumatic artificial muscle actuators.

    Science.gov (United States)

    Wickramatunge, Kanchana Crishan; Leephakpreeda, Thananchai

    2013-11-01

    Pneumatic Artificial Muscle (PAM) actuators yield muscle-like mechanical actuation with high force to weight ratio, soft and flexible structure, and adaptable compliance for rehabilitation and prosthetic appliances to the disabled as well as humanoid robots or machines. The present study is to develop empirical models of the PAM actuators, that is, a PAM coupled with pneumatic control valves, in order to describe their dynamic behaviors for practical control design and usage. Empirical modeling is an efficient approach to computer-based modeling with observations of real behaviors. Different characteristics of dynamic behaviors of each PAM actuator are due not only to the structures of the PAM actuators themselves, but also to the variations of their material properties in manufacturing processes. To overcome the difficulties, the proposed empirical models are experimentally derived from real physical behaviors of the PAM actuators, which are being implemented. In case studies, the simulated results with good agreement to experimental results, show that the proposed methodology can be applied to describe the dynamic behaviors of the real PAM actuators. Copyright © 2013 ISA. Published by Elsevier Ltd. All rights reserved.

  6. Investigations and technical reviews on the reliability of prediction for migration behavior of radionuclides (H15)

    International Nuclear Information System (INIS)

    Tachikawa, Hirokazu

    2004-02-01

    The research plan of the validation on effects of colloids and organic materials drawn up by the Japan Nuclear Fuel Cycle Development Institute and its' research outcome were reviewed comprehensively by an expert committee established in the Nuclear Safety Research Association. Additionally, experimental investigations for the migration behavior of actinide elements and fission products in engineering barrier and natural barrier medias, and for solution chemistry of them were carried out and discussed by the committee, in order to enhance the reliability of prediction for migration behavior of radionuclides. The subjects investigated by the expert committee are as follows: (1) Research on solubility products of An(III) hydroxide. (2) Diffusion and electromigration behavior of plutonium in buffer material. (3) Analysis of the nuclide solubility in compacted bentonite. (4) Survey of the actual contamination by alpha emitters in steel materials. (author)

  7. Measurements of natural and artificial radionuclides in food samples and water for human consumption in Austria for the calculation of the ingestion dose

    International Nuclear Information System (INIS)

    Claudia Landstetter; Michael Zapletal; Merita Sinojmeri; Christian Katzlberger

    2013-01-01

    A new report on food habits of the Austrian population in the year 2006/2007 was released in 2008. Mixed diets and foodstuffs are measured within a monitoring program according to the Austrian radiation protection law, food law, and the Commission Recommendation 2000/473/Euratom on the application of Article 36 of the Euratom Treaty concerning the monitoring of the levels of radioactivity in the environment for the purpose of assessing the exposure of the population as a whole. In addition, drinking and mineral water samples are measured for natural and artificial radionuclides. The ingestion dose for the Austrian population is recalculated based on the results of these measurements, literature data, and the data of the new report on food habits. In general, the major part of the ingestion dose is caused by natural radionuclides, especially 40 K. (author)

  8. Kinetic regularities of change in the concentration of radionuclides in the Georgian tea content

    International Nuclear Information System (INIS)

    Mosulishvili, L.M.; Katamadze, N.M.; Shoniya, N.I.; Ginturi, Eh.N.

    1990-01-01

    The paper is concerned with the results of a study of behavior of artificial radionuclides in Georgian tea technological products after the accident at the Chernobyl Nuclear Station. A partial contribution of the activity of radionuclides 141 Ce, 140 La, 103 Ru, 106 Ru, 140 Ba, 137 Cs, 95 Nb, 95 Zr, 134 Cs and 90 Sr to the total activity to Georgian tea samples. Maximum tolerated concentrations of radionuclides were assessed provided average annual tea consumption per capita was 1 kg. The maximum of solubility in the water phase falls on Cs radionuclides. The regularities of migration of half-lived radionuclides 3 yrs. After the Chernobyl accident were established

  9. Behavior of radionuclides and stable elements in the ecosystem in brackish Lake Obuchi

    International Nuclear Information System (INIS)

    Kondo, Kunio; Ueda, Shinji; Kawabata, Hitoshi; Hasegawa, Hidenao

    1998-01-01

    The behaviors and movements of radionuclides in a brackish environment, Lake Obuchi and its ecosystem were investigated with an aim to evaluate the safety of radioactive materials discharged into the lake. the organic materials in the sediment samples taken from Lake Obuchi were mainly composed of plant planktons and contained various radionuclides; 0.12-1.08 μg/g of 232 Th, 1.69-2.44 μg/g of 238 U, 0.0112-0.0176 Bq/g dry weight. The concentration of stable element was 145.6-357.3 μg/g for Mn, 82.5-128.2 μg/g for Sr, 0.81-1.65 μg/g for Cs and 11.2-16.5 μg/g dry weight for Pb. Plant planktons were found to mediate the accumulation of elements into lake sediments. Therefore, the species composition, distribution and ecological positioning of those planktons were important factors for the behaviors and movements of such elements. Then, the relationship between the concentrations of 137 Cs and Cs was studied with phytoplankton and a positive correlation (r=0.95) was found at both concentrations, suggesting that the adsorptions of the two elements onto the lake sediments were similar. (M.N.)

  10. Implementing Artificial Intelligence Behaviors in a Virtual World

    Science.gov (United States)

    Krisler, Brian; Thome, Michael

    2012-01-01

    In this paper, we will present a look at the current state of the art in human-computer interface technologies, including intelligent interactive agents, natural speech interaction and gestural based interfaces. We describe our use of these technologies to implement a cost effective, immersive experience on a public region in Second Life. We provision our Artificial Agents as a German Shepherd Dog avatar with an external rules engine controlling the behavior and movement. To interact with the avatar, we implemented a natural language and gesture system allowing the human avatars to use speech and physical gestures rather than interacting via a keyboard and mouse. The result is a system that allows multiple humans to interact naturally with AI avatars by playing games such as fetch with a flying disk and even practicing obedience exercises using voice and gesture, a natural seeming day in the park.

  11. Worldwide Open Proficiency Test: Determination of Natural and Artificial Radionuclides in Moss-Soil and Water IAEA-CU-2009-03

    International Nuclear Information System (INIS)

    2012-01-01

    Reliable determination of natural and artificial radionuclides in environmental samples is necessary to comply with radiation protection and environmental regulations. The IAEA assists Member State laboratories in maintaining and improving their readiness by producing reference materials, by developing standardized analytical methods, and by conducting interlaboratory comparisons and proficiency tests as tools for quality control. To fulfil this obligation and ensure a reliable, worldwide, rapid and consistent response, the IAEA Terrestrial Environment Laboratory in Seibersdorf, Austria, organizes interlaboratory comparisons and proficiency tests. This summary report presents the results of the worldwide proficiency test IAEA-CU-2009- 03 on the determination of natural and artificial radionuclides in moss-soil and spiked water. The methodologies, data evaluation approach, summary evaluation of each nuclide and individual evaluation reports for each laboratory are also described. This proficiency test was designed to identify analytical problems, to support Member State laboratories to improve the quality of their analytical results and maintain their accreditation, and to provide a regular forum for discussion and technology transfer in this area. The number of samples, their matrix interferences and the concentration levels of the analytes were designed in a way that enables identification of potential analytical problems.

  12. Individual behavior in learning of an artificial grammar.

    Science.gov (United States)

    Zimmerer, Vitor C; Cowell, Patricia E; Varley, Rosemary A

    2011-04-01

    Artificial grammar learning (AGL) is a widely used experimental paradigm that investigates how syntactic structures are processed. After a familiarization phase, participants have to distinguish strings consistent with a set of grammatical rules from strings that violate these rules. Many experiments report performance solely at a group level and as the total number of correct judgments. This report describes a systematic approach for investigating individual performance and a range of different behaviors. Participants were exposed to strings of the nonfinite grammar A( n )B( n ). To distinguish grammatical from ungrammatical strings, participants had to pay attention to local dependencies while comparing the number of stimuli from each class. Individual participants showed substantially different behavioral patterns despite exposure to the same stimuli. The results were replicated across auditory and visual sensory modalities. It is suggested that an analysis that looks at individual differences grants new insights into the processes involved in AGL. It also provides a solid basis from which to investigate sequence-processing abilities in special populations, such as patients with neurological lesions.

  13. Analysis of nonlinear elastic behavior in miniature pneumatic artificial muscles

    International Nuclear Information System (INIS)

    Hocking, Erica G; Wereley, Norman M

    2013-01-01

    Pneumatic artificial muscles (PAMs) are well known for their excellent actuator characteristics, including high specific work, specific power, and power density. Recent research has focused on miniaturizing this pneumatic actuator technology in order to develop PAMs for use in small-scale mechanical systems, such as those found in robotic or aerospace applications. The first step in implementing these miniature PAMs was to design and characterize the actuator. To that end, this study presents the manufacturing process, experimental characterization, and analytical modeling of PAMs with millimeter-scale diameters. A fabrication method was developed to consistently produce low-cost, high performance, miniature PAMs using commercially available materials. The quasi-static behavior of these PAMs was determined through experimentation on a single actuator with an active length of 39.16 mm (1.54 in) and a diameter of 4.13 mm (0.1625 in). Testing revealed the PAM’s full evolution of force with displacement for operating pressures ranging from 207 to 552 kPa (30–80 psi in 10 psi increments), as well as the blocked force and free contraction at each pressure. Three key nonlinear phenomena were observed: nonlinear PAM stiffness, hysteresis of the force versus displacement response for a given pressure, and a pressure deadband. To address the analysis of the nonlinear response of these miniature PAMs, a nonlinear stress versus strain model, a hysteresis model, and a pressure bias are introduced into a previously developed force balance analysis. Parameters of these nonlinear model refinements are identified from the measured force versus displacement data. This improved nonlinear force balance model is shown to capture the full actuation behavior of the miniature PAMs at each operating pressure and reconstruct miniature PAM response with much more accuracy than previously possible. (paper)

  14. Analysis of nonlinear elastic behavior in miniature pneumatic artificial muscles

    Science.gov (United States)

    Hocking, Erica G.; Wereley, Norman M.

    2013-01-01

    Pneumatic artificial muscles (PAMs) are well known for their excellent actuator characteristics, including high specific work, specific power, and power density. Recent research has focused on miniaturizing this pneumatic actuator technology in order to develop PAMs for use in small-scale mechanical systems, such as those found in robotic or aerospace applications. The first step in implementing these miniature PAMs was to design and characterize the actuator. To that end, this study presents the manufacturing process, experimental characterization, and analytical modeling of PAMs with millimeter-scale diameters. A fabrication method was developed to consistently produce low-cost, high performance, miniature PAMs using commercially available materials. The quasi-static behavior of these PAMs was determined through experimentation on a single actuator with an active length of 39.16 mm (1.54 in) and a diameter of 4.13 mm (0.1625 in). Testing revealed the PAM’s full evolution of force with displacement for operating pressures ranging from 207 to 552 kPa (30-80 psi in 10 psi increments), as well as the blocked force and free contraction at each pressure. Three key nonlinear phenomena were observed: nonlinear PAM stiffness, hysteresis of the force versus displacement response for a given pressure, and a pressure deadband. To address the analysis of the nonlinear response of these miniature PAMs, a nonlinear stress versus strain model, a hysteresis model, and a pressure bias are introduced into a previously developed force balance analysis. Parameters of these nonlinear model refinements are identified from the measured force versus displacement data. This improved nonlinear force balance model is shown to capture the full actuation behavior of the miniature PAMs at each operating pressure and reconstruct miniature PAM response with much more accuracy than previously possible.

  15. The behavior of radionuclides in the soils of Rocky Flats, Colorado

    International Nuclear Information System (INIS)

    Litaor, M.I.; Barth, G.; Zika, E.M.; Litus, G.; Moffitt, J.; Daniels, H.

    1998-01-01

    Radionuclide contamination of soils in Rocky Flats, Colorado, resulted from leaking drums of Pu-contaminated oil stored at an outdoor area. To evaluated the mechanisms of radionuclide transport from the contaminated soils to groundwater, an advanced monitoring system was installed across a toposequence. The impact of natural rain, snowmelt, and large-scale rain simulations on the mobility and distribution of the radionuclides in soil interstitial water was studied. The distribution of radionuclides during the monitoring period from 1993 to 1995 suggested that Pu-239 + 240 and Am-241 are largely immobile in semi-arid soils. Fractionation of Pu-239 + 240 and Am-241 to different particle sizes in the soil interstitial water suggested that most of the radionuclides (83-97%) were associated with suspended particles, whereas the level of radionuclides associated with colloidal (0.45 μm > X > 1 nm) and nonfilterable (< 1 nm) fractions ranged from 1.5 to 15%. (author)

  16. Distribution of artificial radionuclides in abandoned cattle in the evacuation zone of the Fukushima Daiichi nuclear power plant.

    Directory of Open Access Journals (Sweden)

    Tomokazu Fukuda

    Full Text Available The Fukushima Daiichi Nuclear Power Plant (FNPP accident released large amounts of radioactive substances into the environment. In order to provide basic information for biokinetics of radionuclides and for dose assessment of internal exposure brought by the FNPP accident, we determined the activity concentration of radionuclides in the organs of 79 cattle within a 20-km radius around the FNPP. In all the specimens examined, deposition of Cesium-134 ((134Cs, half-life: 2.065 y and (137Cs (30.07 y was observed. Furthermore, organ-specific deposition of radionuclides with relatively short half-lives was detected, such as silver-110m ((110mAg, 249.8 d in the liver and tellurium-129m ((129mTe, 33.6 d in the kidney. Regression analysis showed a linear correlation between the radiocesium activity concentration in whole peripheral blood (PB and that in each organ. The resulting slopes were organ dependent with the maximum value of 21.3 being obtained for skeletal muscles (R(2 = 0.83, standard error (SE = 0.76. Thus, the activity concentration of (134 Cs and (137Cs in an organ can be estimated from that in PB. The level of radioactive cesium in the organs of fetus and infants were 1.19-fold (R(2 = 0.62, SE = 0.12, and 1.51-fold (R(2 = 0.70, SE = 0.09 higher than that of the corresponding maternal organ, respectively. Furthermore, radiocesium activity concentration in organs was found to be dependent on the feeding conditions and the geographic location of the cattle. This study is the first to reveal the detailed systemic distribution of radionuclides in cattle attributed to the FNPP accident.

  17. Distribution of artificial radionuclides in animals in and around the evacuation zone of the Fukushima Daiichi Nuclear Power Plant

    International Nuclear Information System (INIS)

    Fukumoto, Manabu

    2014-01-01

    The Fukushima Daiichi Nuclear Power Plant (FNPP) accident released large amounts of radioactive substances into the environment. We collected organ specimens from over 200 cattle, 50 pigs and 100 monkeys within and adjacent to the 20-km radius previously set as the evacuation zone of FNPP. We have been performing determination of the concentration of radionuclides in the organs of animals. In all the specimens examined, both Cesium-134 ( 134 Cs) and 137 Cs were detectable in a gamma-ray spectrometer and the level of their radioactivity concentrations in each organ was quite similar after the decay correction to March 15, 2011, the day of major release of radionuclides. Linear correlation was found between radioactivity concentration of 137 Cs in whole peripheral blood (PB) and that in each organ. The slope of the regression line was organ dependent and was the highest in the skeletal muscles. The level of 137 Cs in an organ of both fetus and infants was higher than that of the corresponding maternal organ. Over all levels of radioactivity concentration of 137 Cs were dependent on the geological location, the environment and species. Organ-specific deposition of radionuclides with the relatively short half-life was detected, such as 110m Ag in the liver and 129m Te in the kidney of adult cattle. However both 110m Ag and 129m Te were not detectable in any organ of pigs or monkeys. This study is the first to reveal in detail the distribution of radionuclides attributed to the FNPP accident through the entire body of animals. (author)

  18. Release and transport of artificial radionuclides from nuclear weapons related activities in the Ob River, Siberia over the course of the nuclear age

    International Nuclear Information System (INIS)

    Sayles, F.L.; Kenna, T.C.; Livingston, H.D.

    1999-01-01

    Studies of sediment cores from lakes on the flood plain of the Ob River, Siberia have been used to develop a history of the release, transport, and deposition of artificial radionuclides related to the development and testing of nuclear weapons over the duration of the nuclear age (∼1950 to the present) in this major Arctic river system. The Ob is of particular importance in this regard as two of the former Soviet Union's major weapons production plants, Mayak and Tomsk-7, and the Semipalatinsk test site are located within the Ob drainage basin. Accidents and intentional releases of radionuclides at both plants have been substantial, raising the issue of transport throughout this extensive river system as well as delivery to the Arctic Ocean. Our studies have included determining sediment profiles of 239,240 Pu, 137 Cs, and the natural nuclide 210 Pb and its parent 226 Ra in a number of cores from the Ob delta, as well as analysis of 239 Pu, 240 Pu, and 237 Np. The latter provide sensitive measures of the presence of non-fallout materials derived from weapons production activities

  19. Distribution and behavior of radionuclides and stable elements in Lake Obuchi

    International Nuclear Information System (INIS)

    Ueda, Shinji; Hasegawa, Hidenao; Hisamatsu, Shun'ichi; Inaba, Jiro

    2000-01-01

    Distribution and behavior of radionuclides and related stable elements in the lake water of brackish Lake Obuchi were investigated by field observations. Concentrations of 238 U and stable elements were measured at various points in the lake, and compiled to obtain the elemental distributions and variation characteristics. The concentrations of 238 U in the lake water were higher in areas nearer to the Pacific Ocean, and correlated well with those of Na, K, Ca, Mg and Sr (r = 0.86 to 0.92). These observations implied that 238 U in the lake originated from seawater. The bottom layer water was reductive during July and September (stratified period) in deep areas (> 3 m). In this condition, concentrations of PO 4 3- -P, NH 4 + -N, Fe and Mn in the water increased. Concentration ratios of 238 U to those of Na strongly suggested the following conclusions. The concentrations of 238 U in the turn-over period were represented by a simple mixture of seawater and fresh water. However, in the stratified period, part of the 238 U was lost from the seawater near the bottom of the lake due to the reductive condition. (author)

  20. Speciation analysis of radionuclides

    International Nuclear Information System (INIS)

    Salbu, B.

    2010-01-01

    Full text: Naturally occurring and artificially produced radionuclides in the environment can be present in different physico-chemical forms (i. e. radionuclide species) varying in size (nominal molecular mass), charge properties and valence, oxidation state, structure and morphology, density, complexing ability etc. Low molecular mass (LMM) species are believed to be mobile and potentially bioavailable, while high molecular mass (HMM) species such as colloids, polymers, pseudocolloids and particles are considered inert. Due to time dependent transformation processes such as mobilization of radionuclide species from solid phases or interactions of mobile and reactive radionuclide species with components in soils and sediments, however, the original distribution of radionuclides deposited in ecosystems will change over time and influence the ecosystem behaviour. To assess the environmental impact from radionuclide contamination, information on radionuclide species deposited, interactions within affected ecosystems and the time-dependent distribution of radionuclide species influencing mobility and biological uptake is essential. The development of speciation techniques to characterize radionuclide species in waters, soils and sediments should therefore be essential for improving the prediction power of impact and risk assessment models. The present paper reviews fractionation techniques which should be utilised for radionuclide speciation purposes. (author)

  1. Intercomparison measurements of surface soil contamination with in-situ gamma ray spectrometry. Pt.1. Artificial radionuclides

    International Nuclear Information System (INIS)

    Winkelmann, I.

    1994-01-01

    This intercomparison program was performed by the Federal Office of Radiation Protection in October 1993. It includes seven laboratory teams from five countries and is applied on a pasture in southern Germany having an undisturbed soil profile. The location was chosen because of its relatively high 137 Cs-soil contamination caused by the Chernobyl accident - up to 50 kBq/m 2 . The deposition of 134 Cs and 137 Cs was determined. The comparison demonstrated a good agreement between results from different labs. Additionally, the dose rate at all marked locations was measured and compared to the dose rate of individual radionuclides calculated from the measured spectra. A relatively good agreement was obtained. It is shown that the main contribution to the total dose rate of 70 nSv/h is made by 137 Cs with a value of 5 nSv/h. 4 figs., 2 tabs., 3 refs. (orig.)

  2. Effect of microorganisms on the chemical behavior of radionuclides in the environment

    International Nuclear Information System (INIS)

    Amachi, Seigo

    2004-01-01

    Microorganisms are affecting the fate of various radionuclides in the environment through processes such as sorption, accumulation, reduction, leaching and volatilization. We have studied on the microbial influences on the chemical behavior of iodine in the environment, and have isolated various microorganisms which can mediate volatilization, accumulation and oxidation of iodine. We found that iodine-volatilizing bacteria are distributed widely in the environment, and are very diverse group of bacteria. From gas chromatographic analyses, volatile iodine species produced by bacteria was identified as methyl iodide (CH 3 I). Radiotracer experiments were carried out to estimate bacterial contribution to the volatilization of iodine from soils and seawaters. In soil samples, bacteria were considered to play major roles in iodine volatilization since the addition of bacterial inhibitor almost completely inhibited the volatilization. On the other hand, in seawater samples, both bacterial and fungal (or algal) contributions were suggested. We also isolated iodine-accumulating bacteria and iodine-oxidizing bacteria from the environment. Iodine-accumulating bacteria were isolated from marine sediments, and 16S ribosomal DNA sequences showed that they are close to common marine bacteria Flexibacter sp. During the cultivation with iodide ion, they accumulated iodide intracellularly at a concentration that is more than 1,000 times higher than the culture medium. Iodide uptake by iodine-accumulating bacteria was found to occur biologically, and the uptake was specific for iodide but not for iodate. Iodine-oxidizing bacteria, which can mediate iodide (I - ) oxidation to molecular iodine (I 2 ), were phylogenetically divided into two groups within alpha-Proteobacteria, and iodide oxidation was mediated by an extracellular enzyme protein. (author)

  3. Analysis of radionuclide behavior in a BWR Mark-II containment under severe accident management condition in low pressure sequence

    International Nuclear Information System (INIS)

    Funayama, Kyoko; Kajimoto, Mitsuhiro; Nagayoshi, Takuji; Tanaka, Nobuo

    1999-01-01

    In the Level 2 PSA program at INS/NUPEC, MELCOR1.8.3 is extensively applied to analyze radionuclide behavior of dominant sequences. In addition, the revised source terms provided in the NUREG-1465 report have been also discussed to examine the potential of the radionuclides release to the environment in the conventional siting criteria. In the present study, characteristics of source terms to the environment were examined comparing with results by the Hypothetical Accident (LOCA), NUREG-1465 and MELCOR1.8.3. calculation for a typical BWR with a Mark-II containment in order to assure conservatives of the Hypothetical Accident in Japan. Release fractions of iodine to the environment for the Hypothetical Accident and NUREG-1465, which used engineering models for predicting radionuclide behaviors, were about 10 -4 and 10 -6 of core inventory, respectively, while the best estimate MELCOR1.8.3 code predicted 10 -9 of iodine to the environment. The present study showed that the engineering models in the Hypothetical Accident or NUREG-1465 have large conservatives to estimate source term of iodine to the environment. (author)

  4. Log-linear model based behavior selection method for artificial fish swarm algorithm.

    Science.gov (United States)

    Huang, Zhehuang; Chen, Yidong

    2015-01-01

    Artificial fish swarm algorithm (AFSA) is a population based optimization technique inspired by social behavior of fishes. In past several years, AFSA has been successfully applied in many research and application areas. The behavior of fishes has a crucial impact on the performance of AFSA, such as global exploration ability and convergence speed. How to construct and select behaviors of fishes are an important task. To solve these problems, an improved artificial fish swarm algorithm based on log-linear model is proposed and implemented in this paper. There are three main works. Firstly, we proposed a new behavior selection algorithm based on log-linear model which can enhance decision making ability of behavior selection. Secondly, adaptive movement behavior based on adaptive weight is presented, which can dynamically adjust according to the diversity of fishes. Finally, some new behaviors are defined and introduced into artificial fish swarm algorithm at the first time to improve global optimization capability. The experiments on high dimensional function optimization showed that the improved algorithm has more powerful global exploration ability and reasonable convergence speed compared with the standard artificial fish swarm algorithm.

  5. Survey of natural and artificial radionuclide contents in soil samples from some areas of the AP Kosovo (Serbia)

    International Nuclear Information System (INIS)

    Adrovic, Feriz; Kosanovic, Katica; Jakupi, Bajram; Krstic, Gordana; Filipovic, Radmila

    2008-01-01

    After the war conflict in the Autonomous Province of Kosovo and Metohija (Serbia), NATO published data on locations where they used ammunition with depleted uranium. In these regions there were localized points of concentrated contamination, so called 'contamination points'. Taking into consideration the amounts of depleted uranium ammunition used by the NATO, obviously the number of these points in the area of Kosovo and Metohija is not negligible. Within the past 7 years there have been conducted various radiological and other surveys in this area. Majority of these surveys were focused around contamination points. The fact is that so far there has been surveyed only a small percentage of the contaminated area in this region, and apparently there are more contamination points outside the surveyed area. Taking into account the mobility of depleted uranium from contaminated areas by various transportation processes (underground waters, winds and diverse mechanical contacts of people, animals, and other activities), the idea of this work was to investigate possible contamination from depleted uranium not only at the locations indicated and published by the NATO in their reports, but also in the wider area around the zones of NATO strikes. In this paper we presented results of gamma spectrometry analysis of soil samples from wider area of the Autonomous Province of Kosovo and Metohija. We used semiconductor HpGe detector with 30% relative efficiency and the resolution FWHM(1332 keV)=1,78 keV. Spectral analysis were made on the basis of the present gamma lines, using a software package. The activity concentrations of the investigated radionuclides in the soil samples were ranged in the following intervals: 226 Ra from 19 to 55 Bq/kg, 235 U from 1,2 to 4,6 Bq/kg, 238 U from 26 to 95 Bq/kg, 40 K from 83 to 648 Bq/kg, 137 Cs from 1 to 176 Bq/kg. (author)

  6. The study of natural and artificial radionuclides incorporation in teeth and head bones of animals lived nearby Caetité uranium mine, Brazil.

    Science.gov (United States)

    Walencik-Łata, A; Kozłowska, B; Mietelski, J W; Szufa, K; Freire, F D; Souza, S O

    2016-10-01

    This study aimed at assessing the incorporation of radionuclides in animals in the proximity of the uranium mine in Caetité, Brazil. In 2014, samples of bovine and equine teeth and skull bones were collected and their contents of natural and artificial isotopes were assessed using nuclear spectrometry techniques. Gamma ray emission from 226,228 Ra and 40 K isotopes was determined using high-purity germanium (HPGe) spectrometry, 90 Sr radioactivity was measured with liquid scintillation, and 234,238 U, 232,230,228 Th, 210 Po and 239+240 Pu radioactivity was assessed with alpha-spectrometry. Prior to the measurements, sample dissolutions and isotope separations were performed. Our results indicate a high 228 Th isotope content in the skull bones and the teeth of animals, up to 179 Bq per kg of ash. The 226 Ra and 228 Ra concentrations were slightly lower. Activity concentrations of other isotopes were significantly lower or below the detection limit. We could not identify sources of technologically enhanced levels of 228 Ra in the area we investigated; therefore we suggest that their origin is natural. Copyright © 2016 Elsevier Ltd. All rights reserved.

  7. Corrosion behavior of nickel-containing alloys in artificial sweat.

    Science.gov (United States)

    Randin, J P

    1988-07-01

    The corrosion resistance of various nickel-containing alloys was measured in artificial sweat (perspiration) using the Tafel extrapolation method. It was found that Ni, CuNi 25 (coin alloy), NiAl (colored intermetallic compounds), WC + Ni (hard metal), white gold (jewelry alloy), FN42 and Nilo Alby K (controlled expansion alloys), and NiP (electroless nickel coating) are in an active state and dissolve readily in oxygenated artificial sweat. By contrast, austenitic stainless steels, TiC + Mo2C + Ni (hard metal), NiTi (shape-memory alloy), Hastelloy X (superalloy), Phydur (precipitation hardening alloy), PdNi and SnNi (nickel-containing coatings) are in a passive state but may pit under certain conditions. Cobalt, Cr, Ti, and some of their alloys were also investigated for the purpose of comparison. Cobalt and its alloys have poor corrosion resistance except for Stellite 20. Chromium and high-chromium ferritic stainless steels have a high pitting potential but the latter are susceptible to crevice corrosion. Ti has a pitting potential greater than 3 V. Comparison between the in vitro measurements of the corrosion rate of nickel-based alloys and the clinical observation of the occurrence of contact dermatitis is discussed.

  8. Modeling the thermotaxis behavior of C.elegans based on the artificial neural network.

    Science.gov (United States)

    Li, Mingxu; Deng, Xin; Wang, Jin; Chen, Qiaosong; Tang, Yun

    2016-07-03

    ASBTRACT This research aims at modeling the thermotaxis behavior of C.elegans which is a kind of nematode with full clarified neuronal connections. Firstly, this work establishes the motion model which can perform the undulatory locomotion with turning behavior. Secondly, the thermotaxis behavior is modeled by nonlinear functions and the nonlinear functions are learned by artificial neural network. Once the artificial neural networks have been well trained, they can perform the desired thermotaxis behavior. Last, several testing simulations are carried out to verify the effectiveness of the model for thermotaxis behavior. This work also analyzes the different performances of the model under different environments. The testing results reveal the essence of the thermotaxis of C.elegans to some extent, and theoretically support the research on the navigation of the crawling robots.

  9. Behavioral Finance and Agent-Based Artificial Markets

    NARCIS (Netherlands)

    M. Lovric (Milan)

    2011-01-01

    textabstractStudying the behavior of market participants is important due to its potential impact on asset prices and the dynamics of financial markets. The idea of individual investors who are prone to biases in judgment and who use various heuristics, which might lead to anomalies on the market

  10. Artificial Neural Networks: A New Approach for Predicting Application Behavior. AIR 2001 Annual Forum Paper.

    Science.gov (United States)

    Gonzalez, Julie M. Byers; DesJardins, Stephen L.

    This paper examines how predictive modeling can be used to study application behavior. A relatively new technique, artificial neural networks (ANNs), was applied to help predict which students were likely to get into a large Research I university. Data were obtained from a university in Iowa. Two cohorts were used, each containing approximately…

  11. Artificial dirt: microfluidic substrates for nematode neurobiology and behavior.

    Science.gov (United States)

    Lockery, S R; Lawton, K J; Doll, J C; Faumont, S; Coulthard, S M; Thiele, T R; Chronis, N; McCormick, K E; Goodman, M B; Pruitt, B L

    2008-06-01

    With a nervous system of only 302 neurons, the free-living nematode Caenorhabditis elegans is a powerful experimental organism for neurobiology. However, the laboratory substrate commonly used in C. elegans research, a planar agarose surface, fails to reflect the complexity of this organism's natural environment, complicates stimulus delivery, and is incompatible with high-resolution optophysiology experiments. Here we present a new class of microfluidic devices for C. elegans neurobiology and behavior: agarose-free, micron-scale chambers and channels that allow the animals to crawl as they would on agarose. One such device mimics a moist soil matrix and facilitates rapid delivery of fluid-borne stimuli. A second device consists of sinusoidal channels that can be used to regulate the waveform and trajectory of crawling worms. Both devices are thin and transparent, rendering them compatible with high-resolution microscope objectives for neuronal imaging and optical recording. Together, the new devices are likely to accelerate studies of the neuronal basis of behavior in C. elegans.

  12. Workplace Injuries, Safety Climate and Behaviors: Application of Artificial Neural Network.

    Science.gov (United States)

    Abubakar, A Mohammed; Karadal, Himmet; Bayighomog, Steven W; Merdan, Ethem

    2018-03-19

    This article proposes and tests a model of the interaction effect of organizational safety climate and behaviors on workplace injuries. Using artificial neural network and survey data from 306 metal casting industry employees in central Anatolia, we found that organizational safety climate mitigates workplace injuries, and safety behaviors enforces the strength of the negative impact of safety climate on workplace injuries. The results suggest a complex relationship between organizational safety climate, safety behavior, and workplace injuries. Theoretical and practical implications are discussed in light of decreasing workplace injuries in the Anatolian metal casting industry.

  13. Electrochemical behavior of some commercial dental amalgams in artificial saliva.

    Science.gov (United States)

    Cahoon, J R; Regalbuto, C

    1975-01-01

    Cathodic, linear anodic, and anodic polarization studies conducted on three commercial dental amalgams, Caulk Fine Cut Alloy, Spheralloy, and Dispersalloy, showed that all amalgams were in a passive state at the corrosion potential in synthetic saliva solution. The corrosion currents at the corrosion potential were therefore small for all the amalgams, in the range 0.08 to 0.30 muA/cm2. However, the Caulk Fine Cut Alloy and Spheralloy amalgams exhibited a breakdown of passivity and high anodic currents at potentials only approximately equal to 100 mV more noble than the corrosion potential whereas Dispersalloy amalgams maintained passivity at potentials up to 700 mV more noble than the corrosion potential. The breakdown of passivity in Caulk Alloy and Spheralloy amalgams is attributed to the presence of the gamma2 phase (Sn7-8Hg) whereas the passive behavior of Dispersalloy amalgam is attributed to the absence of the phase. It is concluded that none of the amalgams will exhibit severe general corrosion in use, but that both Caulk Alloy and Spheralloy amalgams will exhibit pitting corrosion whereas this type of corrosion should be minimal in Dispersalloy amalgams.

  14. Distribution and behavior of radionuclides in the coastal ecosystem in Rokkasho Village

    International Nuclear Information System (INIS)

    Kondo, Kunio; Kawabata, Hitoshi; Ueda, Shinji; Hasegawa, Hidenao; Inaba, Jiro

    2001-01-01

    The aim of the present study was to elucidate, through both field studies and laboratory experiments, the mechanism for the elution of radionuclides and other materials from suspended organic matter that accompanies the decomposition of organic matter, consisting mainly of phytoplankton, in the coastal sea region off Rokkasho Village. The effect of water temperature on the decomposition rate of organic matter suspended in seawater was investigated in laboratory experiments. The results demonstrated that the decomposition process was divided into two steps for each of the items of dry weight (SS), particulate organic carbon (POC), and particulate organic nitrogen (PON). The first step in decomposition progressed rapidly over several days. The second step of decomposition occurred at a slower rate than the first step. The decomposition rate of organic material was found to be strongly dependent on temperature, with decomposition progressing faster the higher the temperature. The amounts of Mn, Zn, Cu, Pb, Sn, Ni, Be, V, Ti, Ba, Cr, Sr, and the radionuclides 232 Th and 238 Ur eluted from organic matter by decomposition (30 days) of suspended organic matter were in the range of 31-72% of the amounts contained in the organic matter. (author)

  15. Quality assurance in the analysis of natural radionuclides - measures and results

    Energy Technology Data Exchange (ETDEWEB)

    Bothe, M. [Nuclear Engineering and Analytics Rossendorf, Inc. (VKTA), Dresden (Germany)

    1997-03-01

    In the Laboratory for Environmental and Radionuclide Analytics we analyze several natural and also some artificial radionuclides in different materials. For the determination of radionuclides we use various analytical methods. (orig./DG)

  16. Radionuclides in foods

    International Nuclear Information System (INIS)

    1994-01-01

    This report contains data on the levels of radionuclides in the UK foodchain. Most data derive from monitoring programmes that exist around nuclear sites, and in some cases date back to the 1960s. Some comparative data from site operator and government-run programmes are included. Data from monitoring undertaken after the Chernobyl accident are summarised. General monitoring of the foodchain for both artificial and natural radionuclides, and the results of relevant government-sponsored research are also described. The report includes basic information on radioactivity in the environment, radiation protection standards and describes what measures are taken to routinely monitor the foodchain and assess public risk. (Author)

  17. Artificial selection for odor-guided behavior in Drosophila reveals changes in food consumption.

    Science.gov (United States)

    Brown, Elizabeth B; Patterson, Cody; Pancoast, Rayanne; Rollmann, Stephanie M

    2017-11-13

    The olfactory system enables organisms to detect chemical cues in the environment and can signal the availability of food or the presence of a predator. Appropriate behavioral responses to these chemical cues are therefore important for organismal survival and can influence traits such as organismal life span and food consumption. However, understanding the genetic mechanisms underlying odor-guided behavior, correlated responses in other traits, and how these constrain or promote their evolution, remain an important challenge. Here, we performed artificial selection for attractive and aversive behavioral responses to four chemical compounds, two aromatics (4-ethylguaiacol and 4-methylphenol) and two esters (methyl hexanoate and ethyl acetate), for thirty generations. Artificial selection for odor-guided behavior revealed symmetrical responses to selection for each of the four chemical compounds. We then investigated whether selection for odor-guided behavior resulted in correlated responses in life history traits and/or food consumption. We found changes in food consumption upon selection for behavioral responses to aromatics. In many cases, lines selected for increased attraction to aromatics showed an increase in food consumption. We then performed RNA sequencing of lines selected for responses to 4-ethylguaiacol to identify candidate genes associated with odor-guided behavior and its impact on food consumption. We identified 91 genes that were differentially expressed among lines, many of which were associated with metabolic processes. RNAi-mediated knockdown of select candidate genes further supports their role in odor-guided behavior and/or food consumption. This study identifies novel genes underlying variation in odor-guided behavior and further elucidates the genetic mechanisms underlying the interrelationship between olfaction and feeding.

  18. Comparative behavior of three long-lived radionuclides in forest ecosystems

    International Nuclear Information System (INIS)

    Auerbach, S.I.

    1986-01-01

    This paper deals with studies in three forest ecosystems in eastern Tennessee, an area of rich temperate deciduous forests, sometimes referred to as mixed mesophytic forests. Two of these forest ecosystems were contaminated as a result of waste disposal operations. The third was experimentally tagged with millicurie quantities of 137 Cs. One of these ecosystems is a floodplain forest that is typical of this region. This forest has been growing on alluvial soils since 1944. Prior to that time the area was a temporary holding pond within White Oak Creek which received radioactive effluents from ORNL. Radiocesium was deposited in the pond sediments as were 90 Sr, 239 Pu, 241 Am, and other radionuclides. The dam which created the pond failed in late 1944, and the area was allowed to revert to natural conditions. The result was the development of a floodplain forest consisting of three different forest communities. The soils are fertile alluvials representative of bottomlands. The overstory tree species are principally ash, sycamore, boxelder, willow, and sweetgum (Fraxinus americana L., Plantanus occidentalis L., Acer negundo L., Salix nigra Marsh, and Liquidambar styraciflua L., respectively)

  19. Analysis of micro-failure behaviors in artificial muscles based on fishing line and sewing thread

    Science.gov (United States)

    Xu, J. B.; Cheng, K. F.; Tu, S. L.; He, X. M.; Ma, C.; Jin, Y. Z.; Kang, X. N.; Sun, T.; Zhang, Y.

    2017-06-01

    The aim of the present study was to discuss a new and effective method for testing artificial muscles based on micro-failure behaviors analysis. Thermo-mechanical actuators based on fishing line and sewing thread, also, the capability of responding to ambient temperature variations producing a large amount of shrinkage ratio of a resulting variation in longitudinal length. The minimum micro-failure value is 0.02μm and the maximum value is 1.72μm with nylon twist pattern. The discovery of an innovative effective testing of artificial muscles based on polymeric fibers specimens on micro-failure, rupture, slippage, etc. This research finds out a micro-failure behavior analysis of thermo-mechanical actuators based on fishing line and sewing thread. The specimens show large deformations when heated together with warping performance in terms of shrinkage of energy and densities. With the purpose of providing useful analysis data for the further technology applications, we attempt micrometre-sized artificial muscles which were also tested was readily accessible and also can be applied to other polymeric fibers. Effective use of this technique achievement relies on rotate speed, temperature and tensile direction. The results of the tensile testing experiments were outstanding with respect to some important issues related to the response of micro-structure, twisted polymeric fibers and shrinkage ratio.

  20. Estimating the behavior of RC beams strengthened with NSM system using artificial neural networks

    Directory of Open Access Journals (Sweden)

    Seyed Rohollah Hosseini Vaez

    2017-12-01

    Full Text Available In the last decade, conventional materials such as steel and concrete are being replaced by fiber reinforced polymer (FRP materials for the strengthening of concrete structures. Among the strengthening techniques based on Fiber Reinforced Polymer composites, the use of near-surface mounted (NSM FRP rods is emerging as a promising technology for increasing flexural and shear strength of deficient concrete, masonry and timber members. An artificial neural network is an information processing tool that is inspired by the way biological nervous systems (such as the brain process the information. The key element of this tool is the novel structure of the information processing system. In engineering applications, a neural network can be a vector mapper which maps an input vector to an output one. In the present study, a new approach is developed to predict the behavior of strengthened concrete beam using a large number of experimental data by applying artificial neural networks. Having parameters used as input nodes in ANN modeling such as elastic modulus of the FRP reinforcement, the ratio of the steel longitudinal reinforcement, dimensions of the beam section, the ratio of the NSM-FRP reinforcement and characteristics of concrete, the output node was the flexural strength of beams. The idealized neural network was employed to generate empirical charts and equations to be used in design. The aim of this study is to investigate the behavior of strengthened RC beam using artificial neural networks.

  1. Forecast for Artificial Muscle Tremor Behavior Based on Dynamic Additional Grey Catastrophe Prediction

    Directory of Open Access Journals (Sweden)

    Yu Fu

    2018-02-01

    Full Text Available Recently, bio-inspired artificial muscles based on ionic polymers have shown a bright perspective in engineering and medical research, but the inherent tremor behavior can cause instability of output response. In this paper, dynamic additional grey catastrophe prediction (DAGCP is proposed to forecast the occurrence time of tremor behavior, providing adequate preparation time for the suppression of the chitosan-based artificial muscles. DAGCP constructs various dimensions of time subsequence models under different starting points based on the threshold of tremor occurrence times and peak-to-peak values in unit time. Next, the appropriate subsequence is selected according to grey correlation degree and prediction accuracy, then it is updated with the newly generated values to achieve a real-time forecast of forthcoming tremor time. Compared with conventional grey catastrophe prediction (GCP, the proposed method has the following advantages: (1 the degradation of prediction accuracy caused by the immobilization of original parameters is prevented; (2 the dynamic input, real-time update and gradual forecast of time sequence are incorporated into the model. The experiment results show that the novel DAGCP can predict forthcoming tremor time earlier and more accurately than the conventional GCP. The generation mechanism of tremor behavior is illustrated as well.

  2. Comportamento de fungos e de sementes de feijoeiro durante o teste de envelhecimento artificial Behavior of fungi and of bean seeds during the artificial aging test

    Directory of Open Access Journals (Sweden)

    MONALISA ALVES DINIZ DA SILVA

    2000-03-01

    Full Text Available O teste de envelhecimento artificial, recomendado para avaliar o vigor de lotes de sementes, apresenta variabilidade em seus resultados; a ação dos fungos é considerada uma das causas dessa variabilidade. Este trabalho objetivou verificar os efeitos de diferentes períodos de envelhecimento artificial, no comportamento fisiológico de sementes do feijoeiro e dos fungos Aspergillus spp., Penicillium spp., Fusarium oxysporum e Colletotrichum lindemuthianum, inoculados artificialmente. Foram conduzidos testes de sanidade, germinação, tetrazólio, emergência, condutividade elétrica e lixiviação de potássio. As respostas obtidas, dependentes da duração do período de envelhecimento, indicaram efeitos da espécie fúngica presente. Concluiu-se que o teste de envelhecimento artificial associa a expressão de causas fisiológicas e sanitárias, o que prejudica a interpretação dos dados obtidos; a presença de fungos, principalmente de Aspergillus spp., pode ser considerada como capaz de interferir de modo negativo no desempenho das sementes envelhecidas artificialmente.Although recommended for evaluation of seed lot vigor, artificial aging test shows results variability for reasons yet to be elucidated. Seed-fungi association is considered one of the causes responsible for such variation. The goal of this work was to verify the effects of periods of artificial aging on bean seed behavior and on Aspergillus spp., Penicillium spp., Fusarium oxysporum and Colletotrichum lindemuthianum fungi artificially inoculated by contact method. Health, germination, tetrazolium, emergence, electrical conductivity and potassium leaching tests were performed for seed behavior evaluation. The answers achieved, besides dependable on the aging time period, indicated the effect of fungi species associated to the seed. The artificial aging test was found to be associated with the expression of physiological and sanitary causes that interfere with data

  3. Radionuclide carriers

    International Nuclear Information System (INIS)

    Hartman, F.A.; Kretschmar, H.C.; Tofe, A.J.

    1977-01-01

    The invention provides physiologically acceptable particulate radionuclide carriers comprising a reducing agent bound to an anionic starch derivative, useful in the preparation of organ-specific diagnostic radiopharmaceuticals

  4. Artificial intelligence exploration of unstable protocells leads to predictable properties and discovery of collective behavior.

    Science.gov (United States)

    Points, Laurie J; Taylor, James Ward; Grizou, Jonathan; Donkers, Kevin; Cronin, Leroy

    2018-01-30

    Protocell models are used to investigate how cells might have first assembled on Earth. Some, like oil-in-water droplets, can be seemingly simple models, while able to exhibit complex and unpredictable behaviors. How such simple oil-in-water systems can come together to yield complex and life-like behaviors remains a key question. Herein, we illustrate how the combination of automated experimentation and image processing, physicochemical analysis, and machine learning allows significant advances to be made in understanding the driving forces behind oil-in-water droplet behaviors. Utilizing >7,000 experiments collected using an autonomous robotic platform, we illustrate how smart automation cannot only help with exploration, optimization, and discovery of new behaviors, but can also be core to developing fundamental understanding of such systems. Using this process, we were able to relate droplet formulation to behavior via predicted physical properties, and to identify and predict more occurrences of a rare collective droplet behavior, droplet swarming. Proton NMR spectroscopic and qualitative pH methods enabled us to better understand oil dissolution, chemical change, phase transitions, and droplet and aqueous phase flows, illustrating the utility of the combination of smart-automation and traditional analytical chemistry techniques. We further extended our study for the simultaneous exploration of both the oil and aqueous phases using a robotic platform. Overall, this work shows that the combination of chemistry, robotics, and artificial intelligence enables discovery, prediction, and mechanistic understanding in ways that no one approach could achieve alone.

  5. Hormones and the Evolution of Complex Traits: Insights from Artificial Selection on Behavior.

    Science.gov (United States)

    Garland, Theodore; Zhao, Meng; Saltzman, Wendy

    2016-08-01

    Although behavior may often be a fairly direct target of natural or sexual selection, it cannot evolve without changes in subordinate traits that cause or permit its expression. In principle, changes in endocrine function could be a common mechanism underlying behavioral evolution because they are well positioned to mediate integrated responses to behavioral selection. More specifically, hormones can influence both motivational (e.g., brain) and performance (e.g., muscles) components of behavior simultaneously and in a coordinated fashion. If the endocrine system is often "used" as a general mechanism to effect responses to selection, then correlated responses in other aspects of behavior, life history, and organismal performance (e.g., locomotor abilities) should commonly occur because any cell with appropriate receptors could be affected. Ways in which behavior coadapts with other aspects of the phenotype can be studied directly through artificial selection and experimental evolution. Several studies have targeted rodent behavior for selective breeding and reported changes in other aspects of behavior, life history, and lower-level effectors of these organismal traits, including endocrine function. One example involves selection for high levels of voluntary wheel running, one aspect of physical activity, in four replicate High Runner (HR) lines of mice. Circulating levels of several hormones (including insulin, testosterone, thyroxine, triiodothyronine) have been characterized, three of which-corticosterone, leptin, and adiponectin-differ between HR and control lines, depending on sex, age, and generation. Potential changes in circulating levels of other behaviorally and metabolically relevant hormones, as well as in other components of the endocrine system (e.g., receptors), have yet to be examined. Overall, results to date identify promising avenues for further studies on the endocrine basis of activity levels. © The Author 2016. Published by Oxford University

  6. Radionuclide cisternography

    International Nuclear Information System (INIS)

    Song, H.H.

    1980-01-01

    The purpose of this thesis is to show that radionuclide cisternography makes an essential contribution to the investigation of cerebrospinal fluid (CSF) dynamics, especially for the investigation of hydrocephalus. The technical details of radionuclide cisternography are discussed, followed by a description of the normal and abnormal radionuclide cisternograms. The dynamics of CFS by means of radionuclide cisternography were examined in 188 patients in whom some kind of hydrocephalus was suspected. This study included findings of anomalies associated with hydrocephalus in a number of cases, such as nasal liquorrhea, hygromas, leptomeningeal or porencephalic cysts. The investigation substantiates the value of radionuclide cisternography in the diagnosis of disturbances of CSF flow. The retrograde flow of radiopharmaceutical into the ventricular system (ventricular reflux) is an abnormal phenomenon indicating the presence of communicating hydrocephalus. (Auth.)

  7. Environmental behavior of the radionuclides released from the Fukushima Daiichi Nuclear Power Plant accident

    International Nuclear Information System (INIS)

    Yamazaki, Hideo

    2014-01-01

    The environmental behavior of radioactive nuclides released from the Fukushima Daiichi Nuclear Power Station (FDNPS) accident in eastern Japan was investigated. The radioactive pollution of environmental samples, including airborne dust, soil, sediment, fish, and other organisms was described. It was evaluated for environmental behavior and fate of the radioactive material from the spatial and temporal distribution of the radioactive nuclides. In Higashiosaka City about 600 km away from FDNPS, it begins to detect the radioactive nuclides in the airborne dust from 25th March 2011. Radioactive fission products 95 Zr- 95 Nb was detected on 18th April. The concentrations of 131 I, 134 Cs, and 137 Cs in the soil collected from Fukushima City were 126000, 14000, and 14200 Bq/kg on 19th March 2011 and 12800, 13200, and 13700 Bq/kg on 26th March 2011, respectively. The concentrations of 131 I, 134 Cs, and 137 Cs in the soil samples collected from March-June 2011 from study sites in metropolitan area and Kanto region ranged from nd to 91900, 59 to 16100, and 69 to 17600 Bq/kg, respectively. (Concentrations of 131 I were done decay correction to the value of 16th March) Radioactivities in fish samples collected from off FDNPS, Tokyo Bay, and Kejonuma Pond were measured. The radioactive contamination of forest ecosystem was also investigated. Two processes are involved in the radioactive contamination of the environment from the FDNPS accident. One is contamination by radioactive nuclides released from the hydrogen explosion. Leakage of contaminated cooling water to the ocean is in other important environmental pollution. We must continue carefully monitoring of radioactive nuclides in the environment. (author)

  8. Physiological and behavioral responses of Nellore steers to artificial shading in an intensive production system

    Directory of Open Access Journals (Sweden)

    Diogo Alves da Costa Ferro

    2016-09-01

    Full Text Available The influence of artificial shading on environmental variables and on behavioral responses of Nellore steers in an intensive production system was evaluated in this study. The experiment was conducted in the experimental feedlot of the Department of Animal Science at Universidade Estadual de Goiás, from July to October 2014. Forty-eight male Nellore cattle with an average initial weight of 310 kg were kept in double 24-m2 stalls, in a total of 24 stalls. Of these, six were in the open air; six were covered with black shade netting of 30% light interception; six with black shade netting 50%; and six with black shade netting 80%, providing 6 m2 of shade per stall. Temperature-humidity index (THI and respiratory frequency (RF were assessed twice weekly and behavior was evaluated fortnightly during 12 h, between 06:00 h and 18.00 h. Feeding behavior, rumination, rest, and social activities such as body care and playful and abnormal activities were observed. A significant increase was found in THI and RF as the shading levels decreased, while a significant difference was recorded in rest and in other activities, water intake, and play behavior. Rest time and playful behavior increased significantly, and other activities and water intake decreased with the increase in shading levels. Shading does not change the time spent on feeding behaviors and rumination, or the frequencies of urination, defecation, cleaning other animals, self-cleaning, and social and abnormal types of behavior. The use of black shade netting of 80% light interception provides greater comfort to animals, promoting welfare and quality of life to them.

  9. Therapeutic radionuclides

    International Nuclear Information System (INIS)

    Choi, Sun Ju; Hong, Young Don; Lee, So Young

    2006-01-01

    Since the development of sophisticated molecular carriers such as octereotides for peptide receptor targeting and monoclonal antibodies against various associated with specific tumor types, radionuclide therapy (RNT) employing open sources of therapeutic agents is promising modality for treatment of tumors. Furthermore, the emerging of new therapeutic regimes and new approaches for tumor treatment using radionuclide are anticipated in near future. In targeted radiotherapy using peptides and other receptor based carrier molecules, the use of radionuclide with high specific activity in formulating the radiopharmaceutical is essential in order to deliver sufficient number of radionuclides to the target site without saturating the target. In order to develop effective radiopharmaceuticals for therapeutic applications, it is crucial to carefully consider the choice of appropriate radionuclides as well as the carrier moiety with suitable pharmacokinetic properties that could result in good in vivo localization and desired excretion. Up to date, only a limited number of radionuclides have been applied in radiopharmaceutical development due to the constraints in compliance with their physical half-life, decay characteristics, cost and availability in therapeutic applications. In this review article, we intend to provide with the improved understanding of the factors of importance of appropriate radionuclide for therapy with respect to their physical properties and therapeutic applications

  10. Radionuclide cystography

    International Nuclear Information System (INIS)

    Sty, J.R.; Wells, R.G.

    1990-01-01

    This paper reports on radionuclide cystography in infants and children for the detection of vesicoureteral reflux. Vesicoureteral reflux represents a common and potentially serious form of urinary tract pathology. Reflux accompanied by asymptomatic or inadequately treated urinary tract infections has been associated with significant sequelae, including renal scarring, hypertension, and end- stage renal disease. Although there are several advantages and disadvantages to both radionuclide and radiographic techniques for detection of reflux, radionuclide cystography has been found to be at least as sensitive as the voiding cystourethrogram (VCUG) for the detection of clinically significant reflux. The major advantage of radionuclide cystography is a significantly lower radiation dose as compared to VCUG. Both indirect and direct techniques for radionuclide cystography have been developed. In addition to detection of vesicoureteral reflux, indirect radionuclide cystography allows evaluation of differential renal function. Supplemental parameters that may be evaluated with direct radionuclide cystography include: quantitation of reflux, determination of bladder volume at which reflux occurs, evaluation of the dynamics of bladder emptying, and determination of residual bladder volume following voiding

  11. Electrochemical and corrosion behavior of two chromium dental alloys in artificial bioenvironments

    Directory of Open Access Journals (Sweden)

    Banu Alexandra

    2017-01-01

    Full Text Available The purpose of this study is to compare the corrosion and tarnish behavior of NiCrMo and CoCrMo cast dental alloys in artificial bio environments. The cobalt chromium alloys are known and used in dentistry for many years, but its difficult machinability because of the strength and hardness, is an argument for scientists to study alternative materials with comparable biocompatibility. On the other hand, for dentistry devices beside corrosion behavior is important the aesthetic so, the used alloys have to preserve their shining and do not stain. The corrosion resistance has been evaluated using the Atomic mass spectroscopy method for ion release determination, the anodic polarization curves and the open circuit potential – time monitoring for corrosion behavior evaluation and optical microscopy for the structure analysis. The tarnish tendency of alloys was estimated using the method of cyclic immersion with frequency of 10 seconds for each minute during 72 hours in Na2S containing solution. The most important conclusion is that the alloys are comparable from corrosion and tarnish point of view, but we recommend to use the nickel base alloy only for orthodontic devices implanted for short periods of time, because of higher quantity of released ions.

  12. Development and application of an on-line sequential injection system for the separation of artificial and natural radionuclides in environmental samples

    International Nuclear Information System (INIS)

    Kim, C.-K.; Sansone, U.; Martin, P.; Kim, C.-S.

    2007-02-01

    The Chemistry Unit of the Physics, Chemistry and Instrumentation Laboratory in the IAEA's Seibersdorf Laboratory in Austria, has the programmatic responsibility to provide assistance to Member State laboratories in maintaining and improving the reliability of analytical measurement results, both in trace element and radionuclide determinations. This is accomplished through the provision of reference materials of terrestrial origin, validated analytical procedures, training in the implementation of internal quality control, and through the evaluation of measurement performance by organization of worldwide and regional interlaboratory comparison exercises. In this framework an on-line sequential injection (SI) system was developed, which can be widely used for the separation and preconcentration of target analytes from diverse environmental samples. The system enables the separation time to be shortened by maintaining a constant flow rate of solution and by avoiding clogging or bubbling in a chromatographic column. The SI system was successfully applied to the separation of Pu in IAEA reference material (IAEA Soil-6) and to the sequential separation of 210 Po and 210 Pb in phosphogypsum candidate reference material. The replicate analysis results of Pu in IAEA reference material (Soil-6) obtained with the SI system are in good agreement with the recommended value within 5% of standard deviation. The SI system enabled a halving in the separation time required for of radionuclides

  13. Geomorphological applications of environmental radionuclides

    International Nuclear Information System (INIS)

    Quine, T.A.; Walling, D.

    1998-01-01

    Geomorphologists have shown increasing interest in environmental radionuclides since pioneering studies by Ritchie and McHenry in the USA and Campbell, Longmore and Loughran in Australia. Environmental radionuclides have attracted this interest because they provide geomorphologists with the means to trace sediment movement within the landscape. They, therefore, facilitate investigation of subjects at the core of geomorphology, namely the rates and patterns of landscape change. Most attention has been focussed on the artificial radionuclide caesium-137 ( 137 Cs) but more recently potential applications of the natural radionuclides lead-210 ( 210 Pb) and beryllium-7( 7 Be) have been investigated (Walling et al., 1995; Wallbrink and Murray, 1996a, 1996b). The origin, characteristics and applications of these radionuclides are summarised. These radionuclides are of value as sediment tracers because of three important characteristics: a strong affinity for sediment; a global distribution and the possibility of measurement at low concentration. Geomorphological applications of environmental radionuclides provide unique access to detailed qualitative data concerning landscape change over a range of timescales

  14. Radionuclides in food

    International Nuclear Information System (INIS)

    Fernandez Gomez, Isis Maria

    2008-01-01

    The sources of the presence of radionuclides in food are presented: natural radiation and artificial radiation. The transfer of radionuclides through food chains, intakes of radionuclides to the body with its partners effective doses and typical consumption of basic foods of a rural adult population are exposed as main topics. Also the radiation doses from natural sources and exposure to man by ingestion of contaminated food with radionuclides of artificial origin are shown. The contribution of the food ingestion to the man exposure depends on: characteristics of radionuclide, natural conditions, farming practices and eating habits of the population. The principal international organizations in charge of setting guide levels for radionuclides in food are mentioned: standards, rules and the monitoring. It establishes that a guide is necessary for the food monitoring; the alone CODEX ALIMENTARIUS is applicable to emergency situations and the generic action levels proposed by the CODEX not satisfy all needs (no guiding international levels for planned or existing situations such as NORM). There are handled mainly socio-economic and political aspects. Among the actions to be taken are: to assure a public comprehensive information over the risk evaluation in food; to reinforce the collaboration among the different international organizations (WHO, IAEA, ICRP, EC) in relation with the food of set; to give follow-up to the control of the drinkable water and NORM's presence in the food. In addition, it is possible to create the necessary mechanisms to reduce the number of irrelevant measures and bureaucratic useless steps (certificates); to promote the exchange between the different institutions involved in the topic of the food, with relation to the acquired experiences and learned lessons. Likewise, it might examine the possibility of a multidisciplinary approximation (radioactive and not radioactive pollutants); to elaborate a technical guide to assure the

  15. Artificial Outdoor Nighttime Lights Associate with Altered Sleep Behavior in the American General Population

    Science.gov (United States)

    Ohayon, Maurice M.; Milesi, Cristina

    2016-01-01

    Study Objectives: Our study aims to explore the associations between outdoor nighttime lights (ONL) and sleep patterns in the human population. Methods: Cross-sectional telephone study of a representative sample of the general US population age 18 y or older. 19,136 noninstitutionalized individuals (participation rate: 83.2%) were interviewed by telephone. The Sleep-EVAL expert system administered questions on life and sleeping habits; health; sleep, mental and organic disorders (Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Text Revision; International Classification of Sleep Disorders, Second Edition; International Classification of Diseases, 10th Edition). Individuals were geolocated by longitude and latitude. Outdoor nighttime light measurements were obtained from the Defense Meteorological Satellite Program's Operational Linescan System (DMSP/OLS), with nighttime passes taking place between 19:30 and 22:30 local time. Light data were correlated precisely to the geolocation of each participant of the general population sample. Results: Living in areas with greater ONL was associated with delayed bedtime (P sleep duration (P sleep quantity and quality (P sleep behaviors and also impinge on the daytime functioning of individuals living in areas with greater ONL. Citation: Ohayon MM, Milesi C. Artificial outdoor nighttime lights associate with altered sleep behavior in the american general population. SLEEP 2016;39(6):1311–1320. PMID:27091523

  16. A simple artificial life model explains irrational behavior in human decision-making.

    Directory of Open Access Journals (Sweden)

    Carolina Feher da Silva

    Full Text Available Although praised for their rationality, humans often make poor decisions, even in simple situations. In the repeated binary choice experiment, an individual has to choose repeatedly between the same two alternatives, where a reward is assigned to one of them with fixed probability. The optimal strategy is to perseverate with choosing the alternative with the best expected return. Whereas many species perseverate, humans tend to match the frequencies of their choices to the frequencies of the alternatives, a sub-optimal strategy known as probability matching. Our goal was to find the primary cognitive constraints under which a set of simple evolutionary rules can lead to such contrasting behaviors. We simulated the evolution of artificial populations, wherein the fitness of each animat (artificial animal depended on its ability to predict the next element of a sequence made up of a repeating binary string of varying size. When the string was short relative to the animats' neural capacity, they could learn it and correctly predict the next element of the sequence. When it was long, they could not learn it, turning to the next best option: to perseverate. Animats from the last generation then performed the task of predicting the next element of a non-periodical binary sequence. We found that, whereas animats with smaller neural capacity kept perseverating with the best alternative as before, animats with larger neural capacity, which had previously been able to learn the pattern of repeating strings, adopted probability matching, being outperformed by the perseverating animats. Our results demonstrate how the ability to make predictions in an environment endowed with regular patterns may lead to probability matching under less structured conditions. They point to probability matching as a likely by-product of adaptive cognitive strategies that were crucial in human evolution, but may lead to sub-optimal performances in other environments.

  17. Diffusion and Leaching Behavior of Radionuclides in Category 3 Waste Encasement Concrete and Soil Fill Material - Summary Report

    International Nuclear Information System (INIS)

    Mattigod, Shas V.; Wellman, Dawn M.; Bovaird, Chase C.; Parker, Kent E.; Clayton, Libby N.; Powers, Laura; Recknagle, Kurtis P.; Wood, Marcus I.

    2011-01-01

    One of the methods being considered for safely disposing of Category 3 low-level radioactive wastes is to encase the waste in concrete. Such concrete encasement would contain and isolate the waste packages from the hydrologic environment and would act as an intrusion barrier. The current plan for waste isolation consists of stacking low-level waste packages on a trench floor, surrounding the stacks with reinforced steel, and encasing these packages in concrete. These concrete-encased waste stacks are expected to vary in size with maximum dimensions of 6.4 m long, 2.7 m wide, and 4 m high. The waste stacks are expected to have a surrounding minimum thickness of 15 cm of concrete encasement. These concrete-encased waste packages are expected to withstand environmental exposure (solar radiation, temperature variations, and precipitation) until an interim soil cover or permanent closure cover is installed, and to remain largely intact thereafter. Any failure of concrete encasement may result in water intrusion and consequent mobilization of radionuclides from the waste packages. The mobilized radionuclides may escape from the encased concrete by mass flow and/or diffusion and move into the surrounding subsurface environment. Therefore, it is necessary to assess the performance of the concrete encasement structure and the ability of the surrounding soil to retard radionuclide migration. The retardation factors for radionuclides contained in the waste packages can be determined from measurements of diffusion coefficients for these contaminants through concrete and fill material. Some of the mobilization scenarios include (1) potential leaching of waste form before permanent closure cover is installed; (2) after the cover installation, long-term diffusion of radionuclides from concrete waste form into surrounding fill material; (3) diffusion of radionuclides from contaminated soils into adjoining concrete encasement and clean fill material. Additionally, the rate of

  18. Diffusion and Leaching Behavior of Radionuclides in Category 3 Waste Encasement Concrete and Soil Fill Material – Summary Report

    Energy Technology Data Exchange (ETDEWEB)

    Mattigod, Shas V.; Wellman, Dawn M.; Bovaird, Chase C.; Parker, Kent E.; Clayton, Libby N.; Powers, Laura; Recknagle, Kurtis P.; Wood, Marcus I.

    2011-08-31

    One of the methods being considered for safely disposing of Category 3 low-level radioactive wastes is to encase the waste in concrete. Such concrete encasement would contain and isolate the waste packages from the hydrologic environment and would act as an intrusion barrier. The current plan for waste isolation consists of stacking low-level waste packages on a trench floor, surrounding the stacks with reinforced steel, and encasing these packages in concrete. These concrete-encased waste stacks are expected to vary in size with maximum dimensions of 6.4 m long, 2.7 m wide, and 4 m high. The waste stacks are expected to have a surrounding minimum thickness of 15 cm of concrete encasement. These concrete-encased waste packages are expected to withstand environmental exposure (solar radiation, temperature variations, and precipitation) until an interim soil cover or permanent closure cover is installed, and to remain largely intact thereafter. Any failure of concrete encasement may result in water intrusion and consequent mobilization of radionuclides from the waste packages. The mobilized radionuclides may escape from the encased concrete by mass flow and/or diffusion and move into the surrounding subsurface environment. Therefore, it is necessary to assess the performance of the concrete encasement structure and the ability of the surrounding soil to retard radionuclide migration. The retardation factors for radionuclides contained in the waste packages can be determined from measurements of diffusion coefficients for these contaminants through concrete and fill material. Some of the mobilization scenarios include (1) potential leaching of waste form before permanent closure cover is installed; (2) after the cover installation, long-term diffusion of radionuclides from concrete waste form into surrounding fill material; (3) diffusion of radionuclides from contaminated soils into adjoining concrete encasement and clean fill material. Additionally, the rate of

  19. Proficiency testing for radionuclides

    International Nuclear Information System (INIS)

    Faanhof, A.; Kotze, O.; Louw, I.

    2010-01-01

    Proficiency testing in general is only useful when it suites a certain purpose. With regards to radionuclides basically three fields of interest can be identified: (I)Foodstuffs-Introduced in the early 1960's to monitor the fall-out of nuclear tests and eventually the pathway to foodstuffs fit for human consumption. The demand for analysis increased substantially after the Chernobyl accident. (II) Natural radioactivity-Associated with mining and mineral processing of uranium and thorium baring mineral resources throughout the world where the radionuclides from the natural uranium and thorium decay series are found to pose concern for professional and public exposure. (III) Artificial radioactivity-This category covers mostly the long-lived nuclides generated by nuclear fission of the fuel used in nuclear power plants, research reactors and nuclear bomb tests. All three categories require a specific approach for laboratories to test their ability to analyze specific radio nuclides of interest in a variety of matrices. In this lecture I will give a compiled overview of the required radioanalytical skills, analysis sensitivity needed and radionuclides of interest, with more specific emphasis on QAQC of water sources and the recommended monitoring approach. And provide information on available reference materials and organizations/institutes that provide regular exercises for participating laboratories. I will also briefly communicate on the advantages and disadvantages of ISO/IEC 17025 accreditation for test laboratories, which is these days a prerequisite in national and international trade especially where foodstuffs and mineral products are concerned.

  20. Radionuclide carriers

    International Nuclear Information System (INIS)

    Hartman, F.A.; Kretschmar, H.C.

    1976-01-01

    A new carrier for radionuclide technetium 99m has been prepared for scintiscanning purposes. The new preparate consists of physiologically acceptable water-insoluble Tcsup(99m)-carrier containing from 0.2 to 0.8 weight percent of stannic ion as reductor, bound to an anionic starch derivative with about 1-20% of phosphate substituents. (EG)

  1. Fractionation of radionuclide species in the environment

    International Nuclear Information System (INIS)

    Salbu, Brit

    2009-01-01

    Naturally occurring and artificially produced radionuclides in the environment may be present in different physico-chemical forms (i.e., radionuclide species) varying in size (nominal molecular mass), charge properties and valence, oxidation state, structure and morphology, density, degree of complexation, etc. Low molecular mass (LMM) species are believed to be mobile and potentially bioavailable, while high molecular mass (HMM) species such as colloids, polymers, pseudocolloids and particles are considered inert. Due to time-dependent transformation processes such as mobilisation of radionuclide species from solid phases or interactions of mobile and reactive radionuclide species with components in soils and sediments, the original distribution of radionuclides deposited in ecosystems will change over time. To assess the environmental impact from radionuclide contamination, information on radionuclide species deposited, interactions within affected ecosystems and the time-dependent distribution of radionuclide species influencing mobility and biological uptake is essential. The development of speciation techniques to characterize radionuclide species in waters, soils and sediments should therefore be essential for improving the prediction power of impact and risk assessment models. The present paper reviews available fractionation techniques which can be utilised for radionuclide speciation purposes

  2. Retention behavior of flavonoids on immobilized artificial membrane chromatography and correlation with cell-based permeability.

    Science.gov (United States)

    Tsopelas, Fotios; Tsagkrasouli, Maria; Poursanidis, Pavlos; Pitsaki, Maria; Vasios, George; Danias, Panagiotis; Panderi, Irene; Tsantili-Kakoulidou, Anna; Giaginis, Constantinos

    2018-03-01

    The aim of the study was to investigate the immobilized artificial membrane (IAM) retention mechanism for a set of flavonoids and to evaluate the potential of IAM chromatography to model Caco-2 permeability. For this purpose, the retention behavior of 41 flavonoid analogs on two IAM stationary phases, IAM.PC.MG and IAM.PC.DD2, was investigated. Correlations between retention factors, logk w(IAM) and octanol-water partitioning (logP) were established and the role of hydroxyl groups of flavonoids to the underlying retention mechanism was explored. IAM retention and logP values were used to establish sound linear models with Caco-2 permeability (logP app ) taken from the literature. Both stepwise regression and multivariate analysis confirmed the contribution of hydrogen bond descriptors, as additional parameters in the either logk w(IAM) or logP models. Retention factors on both IAM stationary phases showed comparable performance with n-octanol-water partitioning towards Caco-2 permeability. Copyright © 2017 John Wiley & Sons, Ltd.

  3. Patient behavior and the benefits of artificial intelligence: the perils of "dangerous" literacy and illusory patient empowerment.

    Science.gov (United States)

    Schulz, Peter J; Nakamoto, Kent

    2013-08-01

    Artificial intelligence can provide important support of patient health. However, limits to realized benefits can arise as patients assume an active role in their health decisions. Distinguishing the concepts of health literacy and patient empowerment, we analyze conditions that bias patient use of the Internet and limit access to and impact of artificial intelligence. Improving health literacy in the face of the Internet requires significant guidance. Patients must be directed toward the appropriate tools and also provided with key background knowledge enabling them to use the tools and capitalize on the artificial intelligence technology. Benefits of tools employing artificial intelligence to promote health cannot be realized without recognizing and addressing the patients' desires, expectations, and limitations that impact their Internet behavior. In order to benefit from artificial intelligence, patients need a substantial level of background knowledge and skill in information use-i.e., health literacy. It is critical that health professionals respond to patient search for information on the Internet, first by guiding their search to relevant, authoritative, and responsive sources, and second by educating patients about how to interpret the information they are likely to encounter. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  4. Radionuclide transport processes in terrestrial ecosystems

    International Nuclear Information System (INIS)

    Whicker, F.W.

    1983-01-01

    Some major principles and the status of knowledge concerning the transport of radionuclides through terrestrial ecosystems are reviewed. Fundamental processes which control the flow of radionuclides between ecosystem components such as air, soil, plants, and animals are described, with emphasis on deposition, resuspension, plant uptake, ingestion, and assimilation. Properties of radionuclides, organisms, and ecosystems are examined in relation to their influence on the accumulation of radioactive materials by plants and animals. The effects of the physicochemical nature of the radionuclide; morphology, physiology, and behavior of the organism; and soil, nutrient, and trophic characteristics of the ecosystem are highlighted. Observations in natural ecosystems on radionuclides such as 137 Cs, 90 Sr, 131 I, 3 H, and 239 Pu are used to illustrate current concepts. An assessment of the degree to which the processes controlling radionuclide behavior are understood and of our ability to simulate and predict such behavior with computerized models is offered. Finally, brief comments are made on research needs

  5. Anthropogenic radionuclides in the environment

    Energy Technology Data Exchange (ETDEWEB)

    Hu, Q; Weng, J; Wang, J

    2007-11-15

    Studies of radionuclides in the environment have entered a new era with the renaissance of nuclear energy and associated fuel reprocessing, geological disposal of high-level nuclear wastes, and concerns about national security with respect to nuclear non-proliferation. This work presents an overview of anthropogenic radionuclide contamination in the environment, as well as the salient geochemical behavior of important radionuclides. We first discuss the following major anthropogenic sources and current development that contribute to the radionuclide contamination of the environment: (1) nuclear weapons program; (2) nuclear weapons testing; (3) nuclear power plants; (4) commercial fuel reprocessing; (5) geological repository of high-level nuclear wastes, and (6) nuclear accidents. Then, we summarize the geochemical behavior for radionuclides {sup 99}Tc, {sup 129}I, and {sup 237}Np, because of their complex geochemical behavior, long half-lives, and presumably high mobility in the environment. Biogeochemical cycling and environment risk assessment must take into account speciation of these redox-sensitive radionuclides.

  6. Radionuclide techniques

    International Nuclear Information System (INIS)

    Alazraki, N.

    1988-01-01

    During approximately 25 years of experience with bone scanning, broad expansions in the clinical impact of radionuclide imaging on disorders of bones, joints, and soft tissues have occurred. This increased impact had its groundwork laid by advances in radiopharmaceuticals and instruments that are used for bone imaging. The progression from /sup 85/Sr- to /sup 99m/Tc-labeled phosphate and phosphonate compounds, coupled with the advance from crude rectilinear scanning techniques to whole body scintillation imaging with large crystal cameras and sophisticated electronics, has encourage use of radionuclide techniques in the evaluation of muscoloskeletal diseases. Many clinical studies have documented the high degree of sensitivity of the bone scan compared with that of the radiograph in detecting osseous and articular abnormalities

  7. Radionuclide therapy.

    Science.gov (United States)

    Chatal, J F; Hoefnagel, C A

    1999-09-11

    Nuclear medicine therapy uses unsealed radioactive sources for the selective delivery of radiation to tumours or target organs. For benign disorders such as thyrotoxicosis and arthritis radionuclide therapy provides an alternative to surgery or medical treatment. In cancer treatment, it often combines the advantage of target selectivity (like brachytherapy or external beam radiotherapy) with that of being systemic, as with chemotherapy, and it may be used as part of a therapeutic strategy with curative intent or for disease control and palliation. Toxicity is generally limited to the haematopoietic tissue and few side-effects are observed. When cure is feasible, the long-term consequences of radionuclide therapy (eg, fertility disorders and leukaemia or other secondary cancers) do compare favourably with the risks associated with and accepted for chemotherapy and radiotherapy.

  8. Building Behavior Simulation by Means of Artificial Neural Network in Summer Conditions

    Directory of Open Access Journals (Sweden)

    Cinzia Buratti

    2014-08-01

    Full Text Available Many studies in Italy showed that buildings are responsible for about 40% of total energy consumption, due to worsening performance of building envelope; in fact, a great number of Italian buildings were built before the 1970s and 80s. In particular, the energy consumptions for cooling are considerably increased with respect to the ones for heating. In order to reduce the cooling energy demand, ensuring indoor thermal comfort, a careful study on building envelope performance is necessary. Different dynamic software could be used in order to evaluate and to improve the building envelope during the cooling period, but much time and an accurate validation of the model are required. However, when a wide experimental data is available, the Artificial Neural Network (ANN can be an alternative, simple and fast tool to use. In the present study, the indoor thermal conditions in many dwellings built in Umbria Region were investigated in order to evaluate the envelope performance. They were recently built and have very low energy consumptions. Based on the experimental data, a feed forward network was trained, in order to evaluate the different envelopes performance. As input parameters the outdoor climatic conditions and the thermal characteristics of building envelopes were set, while, as a target parameter, the indoor air temperature was provided. A good training of network was obtained with a high regression value (0.9625 and a very small error (0.007 °C on air temperature. The network was also used to simulate the envelope behavior with new innovative glazing systems, in order to evaluate and to improve the energy performance.

  9. Thermal behavior studies in building using artificial neural network for non air conditioned terrace house in Malaysia

    International Nuclear Information System (INIS)

    Zainazlan Md Zain; Mohd Nasir Taib; Shahrizam Mohd Shah Baki

    2006-01-01

    Strategies to improve energy efficiency in buildings have continuously being improved and becoming more effective as new knowledge on the building behavior and technology continue to develop. Nevertheless, effort to explore for further improvement must continuously undertake to seek more energy efficient and cost effective systems. Artificial Neural Network (ANN) is currently one of the most popular mechanisms to forecast any form of behavior and phenomena. Building thermal behavior can be studied and potential for energy utilization improvement without compromising thermal comfort can be explored using ANN. This paper explores the possibility of monitoring, predicting and forecasting the thermal behavior inside a building space and the optimization of building design. Typical result of experimental data and simulated data is presented. The sample house used adopted various thermal comfort strategies like cross ventilation and space air flow consideration

  10. Radionuclide cisternography

    International Nuclear Information System (INIS)

    Staab, E.V.

    1984-01-01

    Cerebrospinal fluid (CSF) scanning, or cisternography, is a diagnostic technique that entails injection of an appropriate radiopharmaceutical into the subarachnoid space and sequential imaging of the spinal and cranial distribution. Radionuclide imaging techniques were originally named according to the spaces of greatest interest and the methods of administration (i.e., myeloscintigraphy, cisternography, and ventriculography). An all-inclusive term, CSF imaging, is now used. The initial studies were made in animals to investigate the physiology of the CSF. DiChiro et al. pioneered the subsequent clinical use in humans to investigate a variety of disorders, including hydrocephalus, leaks, shunt patency, and miscellaneous intracranial cysts

  11. The use of artificial crabs for testing predatory behavior and health in the octopus.

    Science.gov (United States)

    Amodio, Piero; Andrews, Paul; Salemme, Marinella; Ponte, Giovanna; Fiorito, Graziano

    2014-01-01

    The willingness of the cephalopod mollusc Octopus vulgaris to attack a live crab is traditionally used as a method to assess the overall health and welfare of octopuses in the laboratory. This method requires placing a crab in the home tank of an animal, measuring the time (latency) taken for the octopus to initiate an attack and withdrawing the crab immediately prior to capture. The same crab is commonly used to assess multiple octopuses as part of daily welfare assessment. Growing concern for the welfare of crustaceans and a review of all laboratory practices for the care and welfare of cephalopods following the inclusion of this taxon in 2010/63/EU prompted a study of the utility of an artificial crab to replace a live crab in the assessment of octopus health. On consecutive days O. vulgaris (N=21) were presented with a live, a dead or an artificial crab, and the latency to attack measured. Despite differences in the predatory performance towards the three different crab alternatives, octopuses readily attacked the artificial (and the dead) crab, showing that they can generalize and respond appropriately towards artificial prey. Researchers should consider using an artificial crab to replace the use of a live crab as part of the routine health assessment of O. vulgaris.

  12. Factors influencing the transfer of radionuclides in agricultural food chains

    International Nuclear Information System (INIS)

    Vandecasteele, C.M.; Zeevaert, Th.; Kirchmann, R.

    1991-01-01

    The applications of nuclear energy have led and will continue to lead to routine or accidental discharges of radioactive elements into the atmospheric and/or aquatic environment resulting in the exposure of populations to ionising radiations. The radionuclides released into the atmosphere are transported downwind, dispersed by the atmospheric mixing phenomena and progressively settled by deposition processes. During the passage of the radioactive cloud, people are irradiated externally as well as internally by inhalation. After the passage of the cloud, exposure of the population continues via three main pathways: external irradiation from the radionuclides deposited on the ground, inhalation of resuspended contaminated particles and ingestion of contaminated food products. When discharged into aquatic systems, the radionuclides can be partly removed from the aqueous phase by adsorption on suspended solids and bottom sediments. As the radioactivity disperses, there is a continuing exchange between water and solid phases. The contaminated sediments deposited on the banks of rivers, lakes and coastal area lead to external irradiation of people spending time at these sites. The residual activity in water exposes man internally through the ingestion of drinking water and food products, contaminated by irrigation of vegetation and ingestion of water by livestock. Among the various exposure pathways, the main route of entry of fission products and most other artificial radionuclides into man has been identified as uptake from the diet. Since agricultural products constitute the basic diet of most populations, the fate and behavior of radionuclides in agricultural ecosystems are of primary importance when assessing the exposure risk of man from environmental releases of radioactivity. 69 refs., 4 figs

  13. Mobility and Bioavailability of Radionuclides in Soils

    International Nuclear Information System (INIS)

    Iurian, A.; Olufemi Phaneuf, M.; Mabit, L.

    2016-01-01

    It is crucial to understand the behavior of radionuclides in the environment, their potential mobility and bioavailability related to long-term persistence, radiological hazards, and impact on human health. Such key information is used to develop strategies that support policy decisions. The environmental behavior of radionuclides depends on ecosystem characteristics. A given soil’s capacity to immobilize radionuclides has been proved to be the main factor responsible for their resulting activity concentrations in plants. The mobility and bioavailability of radionuclides in soils is complex, depending on clay-sized soil fraction, clay mineralogy, organic matter, cation exchange capacity, pH and quantities of competing cations. Moreover, plant species have different behaviors regarding radionuclide absorption depending on soil and plan characteristics

  14. Statistical analysis of the behavior of fracture toughness of compound bioceramic artificial bone.

    Science.gov (United States)

    Xu, Shilian; Xu, Renping; Li, Ruoqi

    2011-12-01

    We show the manufacturing procedure of the test specimen of the compound bioceramic artificial bone, conduct experiments to measure its fracture toughness, and conclude that the experiment data conform to the two-parameter Weibull distribution with scale parameter β = 0.527369 and form parameter α = 5.24317. Furthermore, compound bioceramic artificial bone is of a high level of crack sensitivity and its data for the fracture toughness is has a high dispersion. We also analyze the evolution of the confidence level of the reliability of its fracture toughness. With the increase of the confidence level γ, the crack sensitivity increases, but the median, the discreteness, and the confidence intervals decrease. The size of the test specimen influences the experiment for the fracture toughness, the measured values and their dispersion, and there exists the conversion between size of the test specimen and that of the real device. We extend the results to introduce the statistic model of the size effect of the fracture toughness. © 2011, Copyright the Authors. Artificial Organs © 2011, International Center for Artificial Organs and Transplantation and Wiley Periodicals, Inc.

  15. Geochemical behavior of radionuclides and heavy metals in soils from Corumbatai River basin (SP), Brazil; Comportamento geoquimico de radionuclideos e metais pesados em solos da bacia do Rio Corumbatai (SP)

    Energy Technology Data Exchange (ETDEWEB)

    Conceicao, Fabiano Tomazini da

    2004-07-01

    The purpose of this research was to study the geochemical behavior of radionuclides and heavy metals in soils of agricultural use at Corumbatai River basin (SP). The natural concentration and variability in sedimentary rocks at Corumbatai river basin follow the trend Ca > Mg > K > Na, with the concentration of heavy metals and radionuclides. The distribution of exposure rate in soils shows the occurrence of higher values towards south of the Corumbatai river basin, region where are applied phosphate fertilizers, amendments and 'vinhaca' in sugar cane crops. Heavy metals and radionuclides incorporated in phosphate fertilizers and amendments are annually added during the fertilization process in the sugar cane crops, but if they are utilized in accordance with the recommended rate, they do not rise the concentration levels in soils up to hazards levels. Thus, they are lower transferred from soils to sugar cane at Corumbatai river basin, not offering hazard to the ecosystem and animal or human health. (author)

  16. Radioactivity and the environment: technical approaches to understand the role of arbuscular mycorrhizal plants in radionuclide bioaccumulation

    Science.gov (United States)

    Davies, Helena S.; Cox, Filipa; Robinson, Clare H.; Pittman, Jon K.

    2015-01-01

    Phytoaccumulation of radionuclides is of significant interest with regards to monitoring radionuclide build-up in food chains, developing methods for environmental bioremediation and for ecological management. There are many gaps in our understanding of the characteristics and mechanisms of plant radionuclide accumulation, including the importance of symbiotically-associated arbuscular mycorrhizal (AM) fungi. We first briefly review the evidence that demonstrates the ability of AM fungi to enhance the translocation of 238U into plant root tissues, and how fungal association may prevent further mobilization into shoot tissues. We then focus on approaches that should further advance our knowledge of AM fungi–plant radionuclide accumulation. Current research has mostly used artificial cultivation methods and we consider how more ecologically-relevant analysis might be performed. The use of synchrotron-based X-ray fluorescence imaging and absorption spectroscopy techniques to understand the mechanisms of radionuclide transfer from soil to plant via AM fungi is evaluated. Without such further knowledge, the behavior and mobilization of radionuclides cannot be accurately modeled and the potential risks cannot be accurately predicted. PMID:26284096

  17. Biodegradation behavior of magnesium and ZK60 alloy in artificial urine and rat models

    Directory of Open Access Journals (Sweden)

    Shiying Zhang

    2017-06-01

    Full Text Available In this work, the biodegradable and histocompatibility properties of pure Mg and ZK60 alloy were investigated as new temporary implants for urinary applications. The corrosion mechanism in artificial urine was proposed using electrochemical impedance spectroscopy and potentiodynamic polarization tests. The corrosion potential of pure magnesium and ZK60 alloy were −1820 and −1561 mV, respectively, and the corrosion current densities were 59.66 ± 6.41 and 41.94 ± 0.53 μA cm−2, respectively. The in vitro degradation rates for pure Mg and ZK60 alloy in artificial urine were 0.382 and 1.023 mm/y, respectively, determined from immersion tests. The ZK60 alloy degraded faster than the pure Mg in both artificial urine and in rat bladders (the implants of both samples are ø 3 mm × 5 mm. Histocompatibility evaluations showed good histocompatibility for the pure Mg and ZK60 alloy during the 3 weeks post-implantation in rat bladders, and no harm was observed in the bladder, liver and kidney tissues. The results provide key information on the degradation properties and corrosion mechanism of pure Mg and ZK60 alloy in the urinary system.

  18. Comparative study on the corrosion behavior of Ti-Nb and TMA alloys for dental application in various artificial solutions

    International Nuclear Information System (INIS)

    Bai, Y.J.; Wang, Y.B.; Cheng, Y.; Deng, F.; Zheng, Y.F.; Wei, S.C.

    2011-01-01

    The corrosion behavior of Ti-Nb dental alloy in artificial saliva with and without the addition of lactic acid and sodium fluoride was investigated by electrochemical techniques, with the commercial Titanium-molybdenum alloy (TMA) as a comparison. The chemical composition, microstructure and constitutional phase were characterized via energy dispersive spectrometry, optical microscope and X-ray diffraction, meanwhile the open circuit potential, electrochemical impedance spectroscopy and potentiodynamic polarization measurements were carried out to study the corrosion resistance of experimental alloys, with the corroded surface being further characterized by scanning electron microscopy and X-ray photoelectron spectroscopy. It was found that the corrosion behavior of Ti-Nb alloy was similar to those TMA alloy samples in both artificial and acidified saliva solutions, whereas statistical analysis of the electrochemical impedance spectroscopy and polarization parameters showed Ti-Nb alloy exhibited better corrosion resistance in fluoridated saliva and fluoridated acidified saliva. SEM observation indicated that TMA alloy corroded heavily than Ti-Nb alloy in fluoride containing saliva. XPS surface analysis suggested that Nb 2 O 5 played an important role in anti-corrosion from the attack of fluoride ion. Based on the above finding, Ti-Nb alloy is believed to be suitable for the usage in certain fluoride treated dental works with excellent corrosion resistance in fluoride-containing oral media.

  19. Concentration of some radionuclides in some popular sudanese medicinal plants

    International Nuclear Information System (INIS)

    Sagiroun, M. I. A.

    2012-10-01

    In this study was measured concentration of naturally occurring radionuclides 2 38U , 2 32T h and 4 0K in samples of sudanese medicinal plants. The radionuclide activity concentrations in samples analyzed ranged from 4.09 to 41.07 Bq kg -1 for 2 38T h and from 353.14 to 2270.21 Bq kg -1 for 4 0k . No trace of artificial radionuclide was determined in all the samples. The effective dose due to the presence of these radionuclides was estimated and found to be 0.524 mSv/year which is well below the permissible levels. (Author)

  20. Feeding behavior by hummingbirds (Aves: Trochilidae in artificial food patches in an Atlantic Forest remnant in southeastern Brazil

    Directory of Open Access Journals (Sweden)

    Lucas L. Lanna

    2017-06-01

    Full Text Available ABSTRACT During flight, hummingbirds achieve the maximum aerobic metabolism rates within vertebrates. To meet such demands, these birds have to take in as much energy as possible, using strategies such as selecting the best food resources and adopting behaviors that allow the greatest energy gains. We tested whether hummingbirds choose sources that have higher sugar concentrations, and investigated their behaviors near and at food resources. The study was conducted at Atlantic forest remnant in Brazil, between June and December 2012. Four patches were provided with artificial feeders, containing sucrose solutions at concentrations of 5%, 15%, 25% and 35% weight/volume. Hummingbird behaviors were recorded using the ad libitum method with continuous recording of behaviors. The following species were observed: the Brazilian ruby Clytolaema rubricauda (Boddaert, 1783, Violet-capped woodnymph Thalurania glaucopis (Gmelin, 1788, Scale-throated hermit Phaethornis eurynome (Lesson, 1832, White-throated hummingbird Leucochloris albicollis (Vieillot, 1818, Versicoloured emerald Amazilia versicolor (Vieillot, 1818, Glittering-bellied emerald Chlorostilbon lucidus (Shaw, 1812 and other Phaethornis spp. C. rubricauda, P. eurynome and Phaethornis spp. visited the 35%-sucrose feeders more often, while the T. glaucopis visited the 25%-sucrose feeders more often. L. albicollis and A. versicolor visited more often solutions with sugar concentration of 15%. C. lucidus visited all patches equally. Three behavioral strategies were observed: 1 C. rubricauda and T. glaucopis exhibited interspecific and intraspecific dominance; 2 the remaining species exhibited subordinance to the dominant hummingbirds, and 3 P. eurynome and Phaethornis spp. adopted a hide-and-wait strategy to the dominant hummingbird species. The frequency of aggressive behaviors was correlated with the time the hummingbird spent feeding, and bird size. Our results showed that hummingbirds can adopt

  1. Final Report (BMWi Project No.: 02 E 10971): Joint project: Retention of radionuclides relevant for final disposal in natural clay rock and saline systems - Subproject 2: Geochemical behavior and transport of radionuclides in saline systems in the prese

    Energy Technology Data Exchange (ETDEWEB)

    Schmeide, Katja [Helmholtz-Zentrum Dresden, (Germany). Inst. of Resource Ecology; Fritsch, Katharina [Helmholtz-Zentrum Dresden, (Germany). Inst. of Resource Ecology; Lippold, Holger [Helmholtz-Zentrum Dresden, (Germany). Inst. of Resource Ecology; Poetsch, Maria [Helmholtz-Zentrum Dresden, (Germany). Inst. of Resource Ecology; Kulenkampff, Johannes [Helmholtz-Zentrum Dresden, (Germany). Inst. of Resource Ecology; Lippmann-Pipke, Johanna [Helmholtz-Zentrum Dresden, (Germany). Inst. of Resource Ecology; Jordan, Norbert [Helmholtz-Zentrum Dresden, (Germany). Inst. of Resource Ecology; Joseph, Claudia [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Helmholtz-Zentrum Dresden, (Germany). Inst. of Resource Ecology; Moll, Henry [Helmholtz-Zentrum Dresden, (Germany). Inst. of Resource Ecology; Cherkouk, Andrea [Helmholtz-Zentrum Dresden, (Germany). Inst. of Resource Ecology; Bader, Miriam [Helmholtz-Zentrum Dresden, (Germany). Inst. of Resource Ecology

    2016-02-29

    The objective of this project was to study the influence of increased salinities on interaction processes in the system radionuclide – organics – clay – aquifer. For this, complexation, redox, sorption, and diffusion studies were performed under variation of the ionic strength (up to 4 mol kg-1) and the background electrolyte (NaCl, CaCl2, MgCl2).

  2. Influence of dynamic load on friction behavior of human articular cartilage, stainless steel and polyvinyl alcohol hydrogel as artificial cartilage.

    Science.gov (United States)

    Li, Feng; Su, Yonglin; Wang, Jianping; Wu, Gang; Wang, Chengtao

    2010-01-01

    Many biomaterials are being developed to be used for cartilage substitution and hemiarthroplasty implants. The lubrication property is a key feature of the artificial cartilage. The frictional behavior of human articular cartilage, stainless steel and polyvinyl alcohol (PVA) hydrogel were investigated under cartilage-on-PVA hydrogel contact, cartilage-on-cartilage contact and cartilage-on-stainless steel contact using pin-on-plate method. Tests under static load, cyclic load and 1 min load change were used to evaluate friction variations in reciprocating motion. The results showed that the lubrication property of cartilage-on-PVA hydrogel contact and cartilage-on-stainless steel contact were restored in both 1 min load change and cyclic load tests. The friction coefficient of PVA hydrogel decreased from 0.178 to 0.076 in 60 min, which was almost one-third of the value under static load in continuous sliding tests. In each test, the friction coefficient of cartilage-on-cartilage contact maintained far lower value than other contacts. It is indicated that a key feature of artificial cartilage is the biphasic lubrication properties.

  3. Development of a patient specific artificial tracheal prosthesis: design, mechanical behavior analysis and manufacturing.

    Science.gov (United States)

    Chua C H, Matthew; Chui, Chee Kong; Rai, Bina; Lau D P, David

    2013-01-01

    There is a need to create patient specific organ replacements as there are differences in the anatomical dimensions among individuals. High failure rates in tracheal prosthesis are attributed to the lack of mechanical strength and flexibility, slow rate of growth of ciliated epithelium and leakage of interstitial fluid into the lumen. This paper proposes a methodology of design, simulations and fabrication of a patient specific artificial tracheal prosthesis for implantation to closely mimic the biomechanical properties of the natural trachea, and describes the prototype device and its materials. Results show that the patient-specific trachea prosthesis has mechanical properties approximate that of normal tracheal rings. The user centric tracheal prosthesis is demonstrated to be a promising candidate for tracheal replacement.

  4. Behavior of TOC in a Deep Confined Aquifer During Groundwater Artificial Recharge Process

    Science.gov (United States)

    Zhang, W.; He, H.; Shi, X.

    2013-12-01

    In recent years, environmental geological problems such as land subsidence, land collapse, land cracking and salt-water intrusion have become important factors limiting economic development in some cities due to severe overexploitation of groundwater. So, a number of cities have carried out artificial recharge projects, which have played a significant role in controlling these problems. However, with the increasing trend of organic pollution appeared in the surface water, organic contaminated problems should not be neglected during this process. Although the organic components were always following in a lower concentration level, whether it would make groundwater face the organic pollution crisis was unknown for its' higher toxicity and durability. Based on a typical artificial recharge test carried out in a deep confined aquifer in this study area (located in Eastern China, there are 10 monitoring wells and 1 recharge well) that decided to control the field land subsidence, Total Organic Carbon (TOC) was selected as the target components to reveal the organic elements' changing trend during groundwater artificial recharge process. The results (Fig. 1) showed that the concentration of TOC in each monitoring well was appeared in an increasing trend due to the mix influence of the recharge water (TOC was 1.88mg/L) and the origin groundwater (TOC was 0.58mg/L). But the maximum concentrations of TOC in J4, J5, J6 monitoring well (the distance from recharge well was 10m, 17m, 31m respectively) were lower than the recharge water 0.28, 0.49, 0.74 mg/L respectively, with non-linear growth. It indicated that except adsorption, microbial degradation might also occur in the aquifer during artificial recharge. With the groundwater environment from relatively anaerobic environment turn to aerobic environment, DO was able to characterize the relative strength of the TOC biodegradation. The average value of DO in recharge water was 4.33 mg/L, and the maximum value of DO in J4, J5

  5. NATURAL AND ARTIFICIAL RADIOACTIVITY IN IMPORTED FISHERY PRODUCTS

    Directory of Open Access Journals (Sweden)

    R. Cavallina

    2013-02-01

    Full Text Available Considering the growing public concern over marine environmental quality, a program of monitoring radionuclids in imported fishery products has been established. The analyses have been performed by gamma spectrometry allowing the rapid detection of many artificial radionuclides such as 137Cs, 134Cs and 40K. The data obtained show Cs radionuclides levels within expected limits. The detection of natural radionuclide K showed different levels in the same fishery product as they came from different sea areas.

  6. Amounts of artificial food colors in commonly consumed beverages and potential behavioral implications for consumption in children.

    Science.gov (United States)

    Stevens, Laura J; Burgess, John R; Stochelski, Mateusz A; Kuczek, Thomas

    2014-02-01

    Artificial food colors (AFCs) are widely used to color foods and beverages. The amount of AFCs the Food and Drug Administration has certified over the years has increased more than 5-fold since 1950 (12 mg/capita/day) to 2012 (68 mg/capita/day). In the past 38 years, there have been studies of adverse behavioral reactions such as hyperactivity in children to double-blind challenges with AFCs. Studies that used 50 mg or more of AFCs as the challenge showed a greater negative effect on more children than those which used less. The study reported here is the first to quantify the amounts of AFCs in foods (specifically in beverages) commonly consumed by children in the United States. Consumption data for all foods would be helpful in the design of more challenge studies. The data summarized here should help clinicians advise parents about AFCs and beverage consumption.

  7. An approach to modeling operator's cognitive behavior using artificial intelligence techniques in emergency operating event sequences

    International Nuclear Information System (INIS)

    Cheon, Se Woo; Sur, Sang Moon; Lee, Yong Hee; Park, Young Taeck; Moon, Sang Joon

    1994-01-01

    Computer modeling of an operator's cognitive behavior is a promising approach for the purpose of human factors study and man-machine systems assessment. In this paper, the states of the art in modeling operator behavior and the current status in developing an operator's model (MINERVA - NPP) are presented. The model is constructed as a knowledge-based system of a blackboard framework and is simulated based on emergency operating procedures

  8. Autoshaped choice in artificial neural networks: implications for behavioral economics and neuroeconomics.

    Science.gov (United States)

    Burgos, José E; García-Leal, Óscar

    2015-05-01

    An existing neural network model of conditioning was used to simulate autoshaped choice. In this phenomenon, pigeons first receive an autoshaping procedure with two keylight stimuli X and Y separately paired with food in a forward-delay manner, intermittently for X and continuously for Y. Then pigeons receive unreinforced choice test trials of X and Y concurrently present. Most pigeons choose Y. This preference for a more valuable response alternative is a form of economic behavior that makes the phenomenon relevant to behavioral economics. The phenomenon also suggests a role for Pavlovian contingencies in economic behavior. The model used, in contrast to others, predicts autoshaping and automaintenance, so it is uniquely positioned to predict autoshaped choice. The model also contemplates neural substrates of economic behavior in neuroeconomics, such as dopaminergic and hippocampal systems. A feedforward neural network architecture was designed to simulate a neuroanatomical differentiation between two environment-behavior relations X-R1 and Y-R2, [corrected] where R1 and R2 denote two different emitted responses (not unconditionally elicited by the reward). Networks with this architecture received a training protocol that simulated an autoshaped-choice procedure. Most networks simulated the phenomenon. Implications for behavioral economics and neuroeconomics, limitations, and the issue of model appraisal are discussed. Copyright © 2015 Elsevier B.V. All rights reserved.

  9. Transcuticular translocation of radionuclides on plant leaf surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Matsumoto, Ken-ichi; Watanabe, Tadakazu; Ambe, Shizuko; Yamaguchi, Isamu [Institute of Physical and Chemical Research, Wako, Saitama (Japan)

    1996-12-31

    The cuticle covering all the outermost surfaces of the aerial parts of plants could play a selective role in uptake and translocation of radionuclides from air into plants. In this study, we investigated the transcuticular uptake and translocation behavior via water droplets of various radionuclides in red clover, orchard grass, Japanese radish and mung bean. Ten {mu}l of an aqueous solution of the multitracer generated from Au was applied to the upper surface of the 2nd leaf of the plants at the 5th leaf stage. The plants were then grown for 14 days at 25degC and 70% RH under illumination of artificial solar lights. The transcuticular uptake and translocation throughout the plant were periodically assayed by determining the radioactivity in the surface residue, the cuticle layer beneath the applied site, the leaf area outside the applied site, the other aerial parts and the root of the plant, using an HPGe detector. The applied radionuclides were absorbed into, in turn, the cuticle layer beneath the applied site and then translocated through the cuticle to the inner tissue and eventually to the other aerial parts and finally to the roots, of the plant. The distribution and accumulation in the plant seems to depend upon the characteristics of each radionuclide and plant species. Ca{sup *} and Te{sup *} tended to remain on leaf surfaces without being absorbed into the cuticle. On the other hand, Sc{sup *}, Co{sup *}, Zn{sup *}, Se{sup *}, Rb{sup *}, and Eu{sup *} were easily absorbed and translocated to every part of the plant including the root. The other radionuclides such as Be{sup *}, Mn{sup *}, Sr{sup *}, Y{sup *}, Ba{sup *}, Ce{sup *}, Pm{sup *}, Gd{sup *}, Hf{sup *}, Yb{sup *}, Lu{sup *}, Os{sup *}, Ir{sup *}, and Pt{sup *} remained in the region close to the site of their application. The above results possibly indicate the existence of mechanisms common to these plants for selective transcuticular uptake and translocation of radionuclides within plant

  10. Corrosion behavior of silver-palladium dental casting alloys in artificial saliva

    Science.gov (United States)

    Krajewski, Katherine Mary

    Ag-Pd dental casting alloys have been used as alternatives to high gold alloys in restorative dentistry since the 1980s. These alloys exhibited mechanical properties superior to gold alloys and excellent adherence to porcelain in porcelain fused to metal (PFM) restorations, such as dental crowns. However, later increases in the price of palladium along with concerns regarding possible allergic reactions and palladium's cytotoxicity have limited the use of these alloys. Evaluation of the biocompatibility concern requires a better understanding of the interaction of Ag-Pd alloys with the oral environment, and the cost problem would be lessened if the palladium content could be reduced without lowering the corrosion resistance. Previous studies have shown differences in the corrosion behavior between Pd-rich and Ag-rich alloys, but the mechanisms of the two behaviors are not well understood. The purpose of this study was to characterize the electrochemical behavior of binary Ag-Pd alloys under conditions simulating the exposure in the oral cavity. Electrochemical measurements, surface and solution analysis were performed with alloy composition, electrolyte composition, and exposure time as variables. Results showed the corrosion behavior for all alloys was governed by the formation of an insoluble thiocyanate salt combined with selective dissolution of Ag for the Pd-rich alloys. The tendency to form thiocyanate was found to dominate over the tendency to form chloride, the formation of which was suggested in other studies. The electrode behavior has been explained on the basis of the theory of behavior of electrodes of the second kind. The difference in behavior of Ag-rich and Pd-rich alloys has been related to the difference in the solubility of the salts and difference in bonding of thiocyanate with Pd and Ag.

  11. Radionuclides in terrestrial ecosystems

    International Nuclear Information System (INIS)

    Allen, S.E.; Horrill, A.D.; Howard, B.J.; Lowe, V.P.W.; Parkinson, J.A.

    1983-07-01

    The subject is discussed under the headings: concentration and spatial distribution of radionuclides in grazed and ungrazed saltmarshes; incorporation of radionuclides by sheep grazing on an estuarine saltmarsh; inland transfer of radionuclides by birds feeding in the estuaries and saltmarshes at Ravenglass; radionuclides in contrasting types of coastal pastures and taken up by individual plant species found in west Cumbria; procedures developed and used for the measurement of alpha and gamma emitters in environmental materials. (U.K.)

  12. Multiscale Modeling of Gene-Behavior Associations in an Artificial Neural Network Model of Cognitive Development

    Science.gov (United States)

    Thomas, Michael S. C.; Forrester, Neil A.; Ronald, Angelica

    2016-01-01

    In the multidisciplinary field of developmental cognitive neuroscience, statistical associations between levels of description play an increasingly important role. One example of such associations is the observation of correlations between relatively common gene variants and individual differences in behavior. It is perhaps surprising that such…

  13. The effects of behavioral and structural assumptions in artificial stock market

    Science.gov (United States)

    Liu, Xinghua; Gregor, Shirley; Yang, Jianmei

    2008-04-01

    Recent literature has developed the conjecture that important statistical features of stock price series, such as the fat tails phenomenon, may depend mainly on the market microstructure. This conjecture motivated us to investigate the roles of both the market microstructure and agent behavior with respect to high-frequency returns and daily returns. We developed two simple models to investigate this issue. The first one is a stochastic model with a clearing house microstructure and a population of zero-intelligence agents. The second one has more behavioral assumptions based on Minority Game and also has a clearing house microstructure. With the first model we found that a characteristic of the clearing house microstructure, namely the clearing frequency, can explain fat tail, excess volatility and autocorrelation phenomena of high-frequency returns. However, this feature does not cause the same phenomena in daily returns. So the Stylized Facts of daily returns depend mainly on the agents’ behavior. With the second model we investigated the effects of behavioral assumptions on daily returns. Our study implicates that the aspects which are responsible for generating the stylized facts of high-frequency returns and daily returns are different.

  14. Radionuclide concentration processes in marine organisms: A comprehensive review.

    Science.gov (United States)

    Carvalho, Fernando P

    2018-06-01

    The first measurements made of artificial radionuclides released into the marine environment did reveal that radionuclides are concentrated by marine biological species. The need to report radionuclide accumulation in biota in different conditions and geographical areas prompted the use of concentration factors as a convenient way to describe the accumulation of radionuclides in biota relative to radionuclide concentrations in seawater. Later, concentration factors became a tool in modelling radionuclide distribution and transfer in aquatic environments and to predicting radioactivity in organisms. Many environmental parameters can modify the biokinetics of accumulation and elimination of radionuclides in marine biota, but concentration factors remained a convenient way to describe concentration processes of radioactive and stable isotopes in aquatic organisms. Revision of CF values is periodically undertaken by international organizations, such as the International Atomic Energy Agency (IAEA), to make updated information available to the international community. A brief commented review of radionuclide concentration processes and concentration factors in marine organisms is presented for key groups of radionuclides such as fission products, activation products, transuranium elements, and naturally-occurring radionuclides. Copyright © 2017 Elsevier Ltd. All rights reserved.

  15. The Spatiotemporal Control of Osteoblast Cell Growth, Behavior, and Function Dictated by Nanostructured Stainless Steel Artificial Microenvironments.

    Science.gov (United States)

    Dhawan, Udesh; Pan, Hsu-An; Shie, Meng-Je; Chu, Ying Hao; Huang, Guewha S; Chen, Po-Chun; Chen, Wen Liang

    2017-12-01

    The successful application of a nanostructured biomaterial as an implant is strongly determined by the nanotopography size triggering the ideal cell response. Here, nanoporous topography on 304L stainless steel substrates was engineered to identify the nanotopography size causing a transition in the cellular characteristics, and accordingly, the design of nanostructured stainless steel surface as orthopedic implants is proposed. A variety of nanopore diameters ranging from 100 to 220 nm were fabricated by one-step electrolysis process and collectively referred to as artificial microenvironments. Control over the nanopore diameter was achieved by varying bias voltage. MG63 osteoblasts were cultured on the nanoporous surfaces for different days. Immunofluorescence (IF) and scanning electron microscopy (SEM) were performed to compare the modulation in cell morphologies and characteristics. Osteoblasts displayed differential growth parameters and distinct transition in cell behavior after nanopore reached a certain diameter. Nanopores with 100-nm diameter promoted cell growth, focal adhesions, cell area, viability, vinculin-stained area, calcium mineralization, and alkaline phosphatase activity. The ability of these nanoporous substrates to differentially modulate the cell behavior and assist in identifying the transition step will be beneficial to biomedical engineers to develop superior implant geometries, triggering an ideal cell response at the cell-nanotopography interface.

  16. Radionuclide antisense therapy

    International Nuclear Information System (INIS)

    Ou Xiaohong

    2002-01-01

    Radionuclide antisense therapy achieves the joint goals of antisense therapy and internal radiation therapy. There have been a small number of investigations on the radionuclide antisense therapy in tissue culture and in animal studies. Considerable research is required before this novel technique can become a working practice. The authors reviewed some question and development on the radionuclide antisense therapy, such as selection of the target gene sequence, labelling the antisense oligonucleotide, improvement of the uptake and target of radionuclide antisense oligonucleotides and evaluation of the toxicity of the radionuclide antisense therapy

  17. Whitefly feeding behavior and retention of a foregut-borne crinivirus exposed to artificial diets with different pH values.

    Science.gov (United States)

    Zhou, Jaclyn S; Chen, Angel Y S; Drucker, Martin; Lopez, Nicole H; Carpenter, Alyssa; Ng, James C K

    2017-12-01

    Transmission of plant viruses by phytophagous hemipteran insects encompasses complex interactions underlying a continuum of processes involved in virus acquisition, retention and inoculation combined with vector feeding behavior. Here, we investigated the effects of dietary pH on whitefly (Bemisia tabaci) feeding behavior and release of Lettuce infectious yellows virus (LIYV) virions retained in the vector's foregut. Electrical penetration graph analysis revealed that variables associated with whitefly probing and ingestion did not differ significantly in pH (4, 7.4, and 9) adjusted artificial diets. To investigate virus retention and release, whiteflies allowed to acquire LIYV virions in a pH 7.4 artificial diet were fed pH 4, 7.4, or 9 virion-free artificial (clearing) diets. Immunofluorescent localization analyses indicated that virions remained bound to the foreguts of approximately 20%-24% of vectors after they fed on each of the 3 pH-adjusted clearing diets. When RNA preparations from the clearing diets were analyzed by reverse transcription (RT) nested-PCR and, in some cases, real-time qPCR, successful amplification of LIYV-specific sequence was infrequent but consistently repeatable for the pH 7.4 diet but never observed for the pH 4 and 9 diets, suggesting a weak pH-dependent effect for virion release. Viruliferous vectors that fed on each of the 3 pH-adjusted clearing diets transmitted LIYV to virus-free plants. These results suggest that changes in pH values alone in artificial diet do not result in observable changes in whitefly feeding behaviors, an observation that marks a first in the feeding of artificial diet by whitefly vectors; and that there is a potential causal and contingent relationship between the pH in artificial diet and the release/inoculation of foregut bound virions. © 2017 Institute of Zoology, Chinese Academy of Sciences.

  18. Joint project. Retention of radionuclides relevant for final disposal in natural clay rock and saline systems. Subproject 2. Geochemical behavior and transport of radionuclides in saline systems in the presence of repository-relevant organics. Final report

    International Nuclear Information System (INIS)

    Schmeide, Katja; Fritsch, Katharina; Lippold, Holger

    2016-01-01

    The objective of this project was to study the influence of increased salinities on interaction processes in the system radionuclide - organics - clay - aquifer. For this purpose, complexation, redox, sorption, and diffusion studies were performed under variation of the ionic strength (up to 4 mol kg -1 ) and the background electrolyte. The U(VI) complexation by propionate was studied in dependence on ionic strength (up to 4 mol kg -1 NaClO 4 ) by TRLFS, ATR FT-IR spectroscopy, and DFT calculations. An influence of ionic strength on stability constants was detected, depending on the charge of the respective complexes. The conditional stability constants, determined for 1:1, 1:2, and 1:3 complexes at specific ionic strengths, were extrapolated to zero ionic strength. The interaction of the bacteria Sporomusa sp. MT-2.99 and Paenibacillus sp. MT-2.2 cells, isolated from Opalinus Clay, with Pu was studied. The experiments can be divided into such without an electron donor where biosorption is favored and such with addition of Na-pyruvate as an electron donor stimulating also bioreduction processes. Moreover, experiments were performed to study the interactions of the halophilic archaeon Halobacterium noricense DSM-15987 with U(VI), Eu(III), and Cm(III) in 3 M NaCl solutions. Research for improving process understanding with respect to the mobility of multivalent metals in systems containing humic matter was focused on the reversibility of elementary processes and on their interaction. Kinetic stabilization processes in the dynamics of humate complexation equilibria were quantified in isotope exchange studies. The influence of high salinity on the mobilizing potential of humic-like clay organics was systematically investigated and was described by modeling. The sorption of Tc(VII)/Tc(IV) onto the iron(II)-containing minerals magnetite and siderite was studied by means of batch sorption experiments, ATR FT-IR and X-ray absorption spectroscopy. The strong Tc retention at

  19. Behavioral Responses of Concholepas concholepas (Bruguière, 1789) Larvae to Natural and Artificial Settlement Cues and Microbial Films.

    Science.gov (United States)

    Rodriguez, S R; Riquelme, C; Campos, E O; Chavez, P; Brandan, E; Inestrosa, N C

    1995-12-01

    The behavioral responses of veliger larvae of the gastropod Concholepas concholepas were studied in the presence of different natural and artificial settlement cues and microbial films. Early pre-competent larvae stopped swimming, sank (due to ciliary arrests, retraction of the velum into the shell, or both), and remained inactive on the substratum when exposed to conspecific mucus and hemolymph. In both cases the effect was time-dependent and the number of larvae showing these behaviors decreased over time. Larvae exposed to NH4Cl (ammonium ion) showed a similar time- and dose-dependent response. A positive and time-dependent response was also observed when larvae were exposed to different extracellular matrix (ECM) components (i.e., collagen, gelatin, and fibronectin) and sulfated polysaccharides (i.e., carrageenan, heparin, and chondroitin sulfate). In this case the larvae remained attached to the substratum. However, the effect of sulfated polysaccharides on C. concholepas larval behavior was faster than that observed with other ECM molecules. We also studied the responses of premetamorphic C. concholepas larvae exposed to different microbial films. In chemotaxis experiments with different films, with glass as the substratum, larvae showed a significant preference for multispecific and diatoms films. When shells of C. concholepas were used as the substratum, the preference for multispecific films was clear and significant. Likewise, larvae showed velar contractions in the presence of all the films tested. Larvae exposed to multispecific films and to the microalga Prasinocladus marinus showed an increased ciliar movement. The finding that mucus and hemolymph of conspecific adults and ECM molecules (mainly sulfated polysaccharides) induce the cessation of swimming of C. concholepas larvae suggests a possible role for cell-surface receptors in mediating the larval response of marine organisms. Likewise, the positive chemotaxis responses of C. concholepas larvae to

  20. Radionuclides in ground-level air

    International Nuclear Information System (INIS)

    Sinkko, K.

    1987-01-01

    In the air surveillance programme the concentrations of artificial radionuclides are monitored in the air close to the ground to obtain the necessary basic data for estimating the exposure of the Finnish population to fall-out radionuclides and also to detect atmospheric traces of radioactive materials caused by their use or production. Airborne dust is collected on filters with high-volume air samplers and the concentrations of gamma-emitting radionuclides in the air are evaluated. In the first quarter of 1986 only long-lived cesium, caused by earlier atmospheric nuclear explosions was detected. The concentrations of cesium were very low. In January and March a small amount of short-lived, fresh fission and activation products were also observed

  1. Study on torsional fretting wear behavior of a ball-on-socket contact configuration simulating an artificial cervical disk

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Song [State Key Laboratory of Tribology, Tsinghua University, Beijing 100084 (China); Department of Mechanical Engineering, Tsinghua University, Beijing 100084 (China); Wang, Fei [School of Material Science and Engineering, China University of Mining and Technology, Xuzhou 221116 (China); Liao, Zhenhua [Department of Mechanical Engineering, Tsinghua University, Beijing 100084 (China); Biomechanics and Biotechnology Lab, Research Institute of Tsinghua University in Shenzhen, Shenzhen 518057 (China); Wang, Qingliang [School of Material Science and Engineering, China University of Mining and Technology, Xuzhou 221116 (China); Liu, Yuhong [State Key Laboratory of Tribology, Tsinghua University, Beijing 100084 (China); Department of Mechanical Engineering, Tsinghua University, Beijing 100084 (China); Liu, Weiqiang, E-mail: weiqliu@hotmail.com [Biomechanics and Biotechnology Lab, Research Institute of Tsinghua University in Shenzhen, Shenzhen 518057 (China); State Key Laboratory of Tribology, Tsinghua University, Beijing 100084 (China)

    2015-10-01

    A ball-on-socket contact configuration was designed to simulate an artificial cervical disk in structure. UHMWPE (ultra high molecular weight polyethylene) hot pressed by powders and Ti6Al4V alloy were selected as the material combination of ball and socket. The socket surface was coated by a ~ 500 nm C-DLC (carbon ion implantation-diamond like carbon) mixed layer to improve its surface nano hardness and wear resistance. The torsional fretting wear behavior of the ball-on-socket model was tested at different angular displacements under 25% bovine serum lubrication with an axial force of 100 N to obtain more realistic results with that in vivo. The fretting running regimes and wear damage characteristics as well as wear mechanisms for both ball and socket were studied based on 2D (two dimension) optical microscope, SEM (scanning electron microscope) and 3D (three dimension) profiles. With the increase of angular displacement amplitude from 1° to 7°, three types of T-θ (Torsional torque-angular displacement amplitude) curves (i.e., linear, elliptical and parallelogram loops) corresponding to running regimes of PSR (partial slip regime), MR (mixed regime) and SR (slip regime) were observed and analyzed. Both the central region and the edge zone of the ball and socket were damaged. The worn surfaces were characterized by wear scratches and wear debris. In addition, more severe wear damage and more wear debris appeared on the central region of the socket at higher angular displacement amplitude. The dominant damage mechanism was a mix of surface scratch, adhesive wear and abrasive wear for the UHMWPE ball while that for the coated socket was abrasive wear by PE particles and some polishing and rolling process on the raised overgrown DLC grains. The frictional kinetic behavior, wear type, damage region and damage mechanism for the ball-on-socket model revealed significant differences with those of a ball-on-flat contact while showing better consistency with that of in

  2. Study on torsional fretting wear behavior of a ball-on-socket contact configuration simulating an artificial cervical disk

    International Nuclear Information System (INIS)

    Wang, Song; Wang, Fei; Liao, Zhenhua; Wang, Qingliang; Liu, Yuhong; Liu, Weiqiang

    2015-01-01

    A ball-on-socket contact configuration was designed to simulate an artificial cervical disk in structure. UHMWPE (ultra high molecular weight polyethylene) hot pressed by powders and Ti6Al4V alloy were selected as the material combination of ball and socket. The socket surface was coated by a ~ 500 nm C-DLC (carbon ion implantation-diamond like carbon) mixed layer to improve its surface nano hardness and wear resistance. The torsional fretting wear behavior of the ball-on-socket model was tested at different angular displacements under 25% bovine serum lubrication with an axial force of 100 N to obtain more realistic results with that in vivo. The fretting running regimes and wear damage characteristics as well as wear mechanisms for both ball and socket were studied based on 2D (two dimension) optical microscope, SEM (scanning electron microscope) and 3D (three dimension) profiles. With the increase of angular displacement amplitude from 1° to 7°, three types of T-θ (Torsional torque-angular displacement amplitude) curves (i.e., linear, elliptical and parallelogram loops) corresponding to running regimes of PSR (partial slip regime), MR (mixed regime) and SR (slip regime) were observed and analyzed. Both the central region and the edge zone of the ball and socket were damaged. The worn surfaces were characterized by wear scratches and wear debris. In addition, more severe wear damage and more wear debris appeared on the central region of the socket at higher angular displacement amplitude. The dominant damage mechanism was a mix of surface scratch, adhesive wear and abrasive wear for the UHMWPE ball while that for the coated socket was abrasive wear by PE particles and some polishing and rolling process on the raised overgrown DLC grains. The frictional kinetic behavior, wear type, damage region and damage mechanism for the ball-on-socket model revealed significant differences with those of a ball-on-flat contact while showing better consistency with that of in

  3. Degradation Behavior of Mg-Ca Nail after Penetration into Artificial Bone

    Science.gov (United States)

    Ikeo, Naoko; Shimizu, Junichi; Ishigaki, Chihiro; Sano, Yuya; Shimizu, Yoshinaka; Mukai, Toshiji

    For applying a magnesium alloy to nails in the guided bone regeneration (GBR) method, sufficient strength and appropriate degradation speed are required to fix a membrane. In the case, the nails are exposed to body fluid after penetrating the alveolar bone. Therefore, in this research, degradation behavior after penetration of magnesium-calcium alloy which is expected to possess high biocompatibility was investigated. As a result, the Mg-Ca alloy nails were degraded inhomogeneously after immersion for 4 weeks in simulated body fluid. The degraded portions corresponded to the distribution of residual strain estimated by finite element analysis. Mg-Ca nails without precipitates possessed comparatively gradual degradation rate. It can be also confirmed that the region with residual strain degraded preferentially when compared the CT images and the residual strain distribution after penetration.

  4. Use of artificial intelligence to shorten the behavioral diagnosis of autism.

    Directory of Open Access Journals (Sweden)

    Dennis P Wall

    Full Text Available The Autism Diagnostic Interview-Revised (ADI-R is one of the most commonly used instruments for assisting in the behavioral diagnosis of autism. The exam consists of 93 questions that must be answered by a care provider within a focused session that often spans 2.5 hours. We used machine learning techniques to study the complete sets of answers to the ADI-R available at the Autism Genetic Research Exchange (AGRE for 891 individuals diagnosed with autism and 75 individuals who did not meet the criteria for an autism diagnosis. Our analysis showed that 7 of the 93 items contained in the ADI-R were sufficient to classify autism with 99.9% statistical accuracy. We further tested the accuracy of this 7-question classifier against complete sets of answers from two independent sources, a collection of 1654 individuals with autism from the Simons Foundation and a collection of 322 individuals with autism from the Boston Autism Consortium. In both cases, our classifier performed with nearly 100% statistical accuracy, properly categorizing all but one of the individuals from these two resources who previously had been diagnosed with autism through the standard ADI-R. Our ability to measure specificity was limited by the small numbers of non-spectrum cases in the research data used, however, both real and simulated data demonstrated a range in specificity from 99% to 93.8%. With incidence rates rising, the capacity to diagnose autism quickly and effectively requires careful design of behavioral assessment methods. Ours is an initial attempt to retrospectively analyze large data repositories to derive an accurate, but significantly abbreviated approach that may be used for rapid detection and clinical prioritization of individuals likely to have an autism spectrum disorder. Such a tool could assist in streamlining the clinical diagnostic process overall, leading to faster screening and earlier treatment of individuals with autism.

  5. Artificial Outdoor Nighttime Lights Associate with Altered Sleep Behavior in the American General Population.

    Science.gov (United States)

    Ohayon, Maurice M; Milesi, Cristina

    2016-06-01

    Our study aims to explore the associations between outdoor nighttime lights (ONL) and sleep patterns in the human population. Cross-sectional telephone study of a representative sample of the general US population age 18 y or older. 19,136 noninstitutionalized individuals (participation rate: 83.2%) were interviewed by telephone. The Sleep-EVAL expert system administered questions on life and sleeping habits; health; sleep, mental and organic disorders (Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Text Revision; International Classification of Sleep Disorders, Second Edition; International Classification of Diseases, 10(th) Edition). Individuals were geolocated by longitude and latitude. Outdoor nighttime light measurements were obtained from the Defense Meteorological Satellite Program's Operational Linescan System (DMSP/OLS), with nighttime passes taking place between 19:30 and 22:30 local time. Light data were correlated precisely to the geolocation of each participant of the general population sample. Living in areas with greater ONL was associated with delayed bedtime (P sleep duration (P sleep quantity and quality (P sleep behaviors and also impinge on the daytime functioning of individuals living in areas with greater ONL. © 2016 Associated Professional Sleep Societies, LLC.

  6. Behavior of nine selected emerging trace organic contaminants in an artificial recharge system supplemented with a reactive barrier.

    Science.gov (United States)

    Valhondo, Cristina; Carrera, Jesús; Ayora, Carlos; Barbieri, Manuela; Nödler, Karsten; Licha, Tobias; Huerta, Maria

    2014-10-01

    Artificial recharge improves several water quality parameters, but has only minor effects on recalcitrant pollutants. To improve the removal of these pollutants, we added a reactive barrier at the bottom of an infiltration basin. This barrier contained aquifer sand, vegetable compost, and clay and was covered with iron oxide dust. The goal of the compost was to sorb neutral compounds and release dissolved organic carbon. The release of dissolved organic carbon should generate a broad range of redox conditions to promote the transformation of emerging trace organic contaminants (EOCs). Iron oxides and clay increase the range of sorption site types. In the present study, we examined the effectiveness of this barrier by analyzing the fate of nine EOCs. Water quality was monitored before and after constructing the reactive barrier. Installation of the reactive barrier led to nitrate-, iron-, and manganese-reducing conditions in the unsaturated zone below the basin and within the first few meters of the saturated zone. Thus, the behavior of most EOCs changed after installing the reactive barrier. The reactive barrier enhanced the removal of some EOCs, either markedly (sulfamethoxazole, caffeine, benzoylecgonine) or slightly (trimethoprim) and decreased the removal rates of compounds that are easily degradable under aerobic conditions (ibuprofen, paracetamol). The barrier had no remarkable effect on 1H-benzotriazole and tolyltriazole.

  7. Deposition behavior of polystyrene latex particles on solid surfaces during migration through an artificial fracture in a granite rock sample

    International Nuclear Information System (INIS)

    Chinju, Hirofumi; Tanaka, Satoru; Kuno, Yoshio

    2001-01-01

    The deposition behavior of colloids during transport through heterogeneous media was observed by conducting column experiments to study migration of polystyrene latex particles (diameter=309 nm) through columns packed with artificially fractured granite rock (length=300 and 150 mm). The experiments were conducted under conditions of different ionic strengths and flow rates. The results were similar to those for colloid deposition in columns packed with glass beads reported previously; the colloid breakthrough curves showed three stages, characterized by different rates of change in the concentration of effluent. Colloid deposition on the fracture surfaces was described by considering strong and weak deposition sites. Scanning Electron Microscopy (SEM) observations indicated the existence of strong and weak sites on the fracture surfaces regardless of mineral composition. The observations also showed that the strong deposition sites tended to exist on surface irregularities such as cracks or protrusions. The degree of colloid deposition increased with increasing ionic strength and decreasing flow rate. The dependencies on ionic strength and flow rate agreed qualitatively with the DLVO theory and the previous experimental results, respectively. (author)

  8. Quantitative radionuclide angiocardiography

    International Nuclear Information System (INIS)

    Scholz, P.M.; Rerych, S.K.; Moran, J.F.; Newman, G.E.; Douglas, J.M.; Sabiston, D.C. Jr.; Jones, R.H.

    1980-01-01

    This study introduces a new method for calculating actual left ventricular volumes and cardiac output from data recorded during a single transit of a radionuclide bolus through the heart, and describes in detail current radionuclide angiocardiography methodology. A group of 64 healthy adults with a wide age range were studied to define the normal range of hemodynamic parameters determined by the technique. Radionuclide angiocardiograms were performed in patients undergoing cardiac catherization to validate the measurements. In 33 patients studied by both techniques on the same day, a close correlation was documented for measurement of ejection fraction and end-diastolic volume. To validate the method of volumetric cardiac output calcuation, 33 simultaneous radionuclide and indocyanine green dye determinations of cardiac output were performed in 18 normal young adults. These independent comparisons of radionuclide measurements with two separate methods document that initial transit radionuclide angiocardiography accurately assesses left ventricular function

  9. Exposure-dose research for radionuclides in natural gas

    International Nuclear Information System (INIS)

    McNelis, D.N.; Patzer, R.G.

    1969-01-01

    The fate determination of specific radionuclides in natural gas stimulated by underground engineering applications is being examined. An experimental program, now in its initial stages, is using gas artificially labeled with krypton-85 and tritium under simulated domestic situations. The following topics are being investigated in this study: 1. The concentration of the radionuclides in a gas-heated home. 2. The build-up of contamination on appliances in the kitchen environment. 3. The concentration in foods as a function of radionuclide, food type and preparation. 4. The maximum exposure plausible under specified conditions. (author)

  10. Marine biogeochemistry of radionuclides

    International Nuclear Information System (INIS)

    Fowler, S.W.

    1997-01-01

    Radionuclides entering the ocean from runoff, fallout, or deliberate release rapidly become involved in marine biogeochemical cycles. Sources, sinks and transport of radionuclides and analogue elements are discussed with emphasis placed on how these elements interact with marine organisms. Water, food and sediments are the source terms from which marine biota acquire radionuclides. Uptake from water occurs by surface adsorption, absorption across body surfaces, or a combination of both. Radionuclides ingested with food are either assimilated into tissue or excreted. The relative importance of the food and water pathway in uptake varies with the radionuclide and the conditions under which exposure occurs. Evidence suggests that, compared to the water and food pathways, bioavailability of sediment-bound radionuclides is low. Bioaccumulation processes are controlled by many environmental and intrinsic factors including exposure time, physical-chemical form of the radionuclide, salinity, temperature, competitive effects with other elements, organism size, physiology, life cycle and feeding habits. Once accumulated, radionuclides are transported actively by vertical and horizontal movements of organisms and passively by release of biogenic products, e.g., soluble excreta, feces, molts and eggs. Through feeding activities, particles containing radionuclides are ''packaged'' into larger aggregates which are redistributed upon release. Most radionuclides are not irreversibly bound to such particles but are remineralized as they sink and/or decompose. In the pelagic zones, sinking aggregates can further scavenge particle-reactive elements thus removing them from the surface layers and transporting them to depth. Evidence from both radiotracer experiments and in situ sediment trap studies is presented which illustrates the importance of biological scavenging in controlling the distribution of radionuclides in the water column. (author)

  11. Radionuclide evaluation of brain death

    International Nuclear Information System (INIS)

    Pjura, G.A.; Kim, E.E.

    1987-01-01

    The criteria employed for clinical determination of death have evolved in response to advances in life support and other medical technology. The technical feasibility of organ transplantation has amplified the need for a definition of brain death that can be applied in the shortest possible time in the presence of artificial maintenance of vegetative functions, including circulation. Radionuclide cerebral angiography is one of a group of diagnostic procedures that can be employed to confirm the clinical diagnosis of brain death through demonstration of absence of cerebral blood flow. The focus of this work is to assess its use as a confirmatory test for determination of brain death in the context of currently available alternative technologies

  12. Radionuclides in terrestrial ecosystems

    International Nuclear Information System (INIS)

    Bocock, K.L.

    1981-01-01

    This report summarizes information on the distribution and movement of radionuclides in semi-natural terrestrial ecosystems in north-west England with particular emphasis on inputs to, and outputs from ecosystems; on plant and soil aspects; and on radionuclides in fallout and in discharges by the nuclear industry. (author)

  13. Chaotic behavior control in fluidized bed systems using artificial neural network. Quarterly progress report, April 1, 1996--June 30, 1996

    Energy Technology Data Exchange (ETDEWEB)

    Bodruzzaman, M.; Essawy, M.A.

    1996-07-30

    We have developed techniques to control the chaotic behavior in the Fluidized Bed (FBC) Systems using Artificial Neural Networks (ANNs). For those techniques to cross from theory to implementation, the computer programs we are developing have to be interfaced with the outside world, as a necessary step towards the actual interface with an FBC system or its experimental mock up. For this reason we are working on a Data Acquisition Board setup that will enable communication between our programs and external systems. Communication is planned to be enabled in both ways to deliver feedback signals from a system to the control programs in one way, and the control signals from the control programs to the controlled system in the other way. On the other hand, since most of our programs are PC based, they have to follow the revolutionary progress in the PC technology. Our programs were developed in the DOS environment using an early version of Microsoft C compiler. For those programs to meet the current needs of most PC users, we are working on converting those programs to the Windows environment, using a very advanced and up to date C++ compiler. This compiler is known as the Microsoft Visual C++ Version 4.0. This compiler enables the implementation of very professional and sophisticated Windows 95, 32 bit applications. It also allows a simple utilization of the Object Oriented Programming (OOP) techniques, and lots of powerful graphical and communication tools known as the Microsoft Foundation Classes (MFC). This compiler also allows creating Dynamic Link Libraries (DLLS) that can be liked together or with other Windows programs. These two main aspects, the computer-system interface and the DOS-Windows migration will give our programs a leap frog towards their real implementation.

  14. Radionuclides as tracers of coastal processes in Brazil: review, synthesis, and perspectives

    OpenAIRE

    Santos,Isaac R.; Burnett,William C.; Godoy,José M.

    2008-01-01

    We review the usefulness, limitations, significance, and coastal management implications of radionuclide measurements in Brazilian coastal environments. We focus on the use of radionuclides as tracers of sedimentary processes and submarine groundwater discharge (SGD). We also discuss artificial radionuclide contamination and high natural radioactivity areas. The interpretation of 14C-, 137Cs-, and 210Pb-derived sedimentation rates has provided evidence that inappropriate soil use by urban and...

  15. Study on torsional fretting wear behavior of a ball-on-socket contact configuration simulating an artificial cervical disk.

    Science.gov (United States)

    Wang, Song; Wang, Fei; Liao, Zhenhua; Wang, Qingliang; Liu, Yuhong; Liu, Weiqiang

    2015-10-01

    A ball-on-socket contact configuration was designed to simulate an artificial cervical disk in structure. UHMWPE (ultra high molecular weight polyethylene) hot pressed by powders and Ti6Al4V alloy were selected as the material combination of ball and socket. The socket surface was coated by a ~500 nm C-DLC (carbon ion implantation-diamond like carbon) mixed layer to improve its surface nano hardness and wear resistance. The torsional fretting wear behavior of the ball-on-socket model was tested at different angular displacements under 25% bovine serum lubrication with an axial force of 100 N to obtain more realistic results with that in vivo. The fretting running regimes and wear damage characteristics as well as wear mechanisms for both ball and socket were studied based on 2D (two dimension) optical microscope, SEM (scanning electron microscope) and 3D (three dimension) profiles. With the increase of angular displacement amplitude from 1° to 7°, three types of T-θ (Torsional torque-angular displacement amplitude) curves (i.e., linear, elliptical and parallelogram loops) corresponding to running regimes of PSR (partial slip regime), MR (mixed regime) and SR (slip regime) were observed and analyzed. Both the central region and the edge zone of the ball and socket were damaged. The worn surfaces were characterized by wear scratches and wear debris. In addition, more severe wear damage and more wear debris appeared on the central region of the socket at higher angular displacement amplitude. The dominant damage mechanism was a mix of surface scratch, adhesive wear and abrasive wear for the UHMWPE ball while that for the coated socket was abrasive wear by PE particles and some polishing and rolling process on the raised overgrown DLC grains. The frictional kinetic behavior, wear type, damage region and damage mechanism for the ball-on-socket model revealed significant differences with those of a ball-on-flat contact while showing better consistency with that of in

  16. Radionuclide release from PWR spent fuel specimens with induced cladding defects

    International Nuclear Information System (INIS)

    Wilson, C.N.; Oversby, V.M.

    1984-03-01

    Radionuclide releases from pressurized water reactor (PWR) spent fuel rod specimens containing various artificially induced cladding defects were compared by leach testing. The study was conducted in support of the Nevada Nuclear Waste Storage Investigations (NNWSI) Waste Package Task to evaluate the effectiveness of failed cladding as a barrier to radionuclide release. Test description and results are presented. 6 references, 4 figures

  17. Selected radionuclides important to low-level radioactive waste management

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-11-01

    The purpose of this document is to provide information to state representatives and developers of low level radioactive waste (LLW) management facilities about the radiological, chemical, and physical characteristics of selected radionuclides and their behavior in the environment. Extensive surveys of available literature provided information for this report. Certain radionuclides may contribute significantly to the dose estimated during a radiological performance assessment analysis of an LLW disposal facility. Among these are the radionuclides listed in Title 10 of the Code of Federal Regulations Part 61.55, Tables 1 and 2 (including alpha emitting transuranics with half-lives greater than 5 years). This report discusses these radionuclides and other radionuclides that may be significant during a radiological performance assessment analysis of an LLW disposal facility. This report not only includes essential information on each radionuclide, but also incorporates waste and disposal information on the radionuclide, and behavior of the radionuclide in the environment and in the human body. Radionuclides addressed in this document include technetium-99, carbon-14, iodine-129, tritium, cesium-137, strontium-90, nickel-59, plutonium-241, nickel-63, niobium-94, cobalt-60, curium -42, americium-241, uranium-238, and neptunium-237.

  18. Selected radionuclides important to low-level radioactive waste management

    International Nuclear Information System (INIS)

    1996-11-01

    The purpose of this document is to provide information to state representatives and developers of low level radioactive waste (LLW) management facilities about the radiological, chemical, and physical characteristics of selected radionuclides and their behavior in the environment. Extensive surveys of available literature provided information for this report. Certain radionuclides may contribute significantly to the dose estimated during a radiological performance assessment analysis of an LLW disposal facility. Among these are the radionuclides listed in Title 10 of the Code of Federal Regulations Part 61.55, Tables 1 and 2 (including alpha emitting transuranics with half-lives greater than 5 years). This report discusses these radionuclides and other radionuclides that may be significant during a radiological performance assessment analysis of an LLW disposal facility. This report not only includes essential information on each radionuclide, but also incorporates waste and disposal information on the radionuclide, and behavior of the radionuclide in the environment and in the human body. Radionuclides addressed in this document include technetium-99, carbon-14, iodine-129, tritium, cesium-137, strontium-90, nickel-59, plutonium-241, nickel-63, niobium-94, cobalt-60, curium -42, americium-241, uranium-238, and neptunium-237

  19. Process for encapsulating radionuclides

    International Nuclear Information System (INIS)

    Brownell, L.E.; Isaacson, R.E.

    1976-01-01

    Radionuclides are immobilized in virtually an insoluble form by reacting at a temperature of at least 90 0 C as an aqueous alkaline mixture having a solution pH of at least 10, containing a source of silicon, the radionuclide waste, and a metal cation. The molar ratio of silicon to the metal cation is on the order of unity to produce a gel from which complex metalosilicates crystallize to entrap the radionuclides within the resultant condensed crystal lattice. The product is a silicious stone-like material which is virtually insoluble and nonleachable in alkaline or neutral environment. One embodiment provides for the formation of the complex metalo-silicates, such as synthetic pollucite, by gel formation with subsequent calcination to the solid product; another embodiment utilizes a hydrothermal process, either above ground or deep within basalt caverns, at greater than atmospheric pressures and a temperature between 90 and 500 0 C to form complex metalo-silicates, such as strontium aluminosilicate. Another embodiment provides for the formation of complex metalo-silicates, such as synthetic pollucite, by slurrying an alkaline mixture of bentonite or kaolinite with a source of silicon and the radionuclide waste in salt form. In each of the embodiments a mobile system is achieved whereby the metalo-silicate constituents reorient into a condensed crystal lattice forming a cage structure with the condensed metalo-silicate lattice which completely surrounds the radionuclide and traps the radionuclide therein; thus rendering the radionuclide virtually insoluble

  20. Dynamic effects of tank waste aging on radionuclide-complexant interactions. 1998 annual progress report

    International Nuclear Information System (INIS)

    Arterburn, J.B.; Chamberlin, R.

    1998-01-01

    'The overall objective of this project is to provide a scientific basis for safely processing complexant-containing high-level tank wastes for disposal. The key goals are to identify a means to prepare realistic complexant-containing tank waste simulants, and to use those simulants to determine the relative importance of organic complexants and their breakdown products on the partitioning of important radionuclides. These goals will be accomplished by artificially aging complexant-containing tank waste simulants using microwave, ultrasound, and photolysis techniques. The simulants will be compared to samples of actual Hanford tank wastes to determine the most realistic aging method, on the basis of the organic fragmentation and the partitioning behavior of the important radionuclides 90 Sr, 99 Tc, and 239 Pu. Also, the authors will use their simulant aging process to investigate the relative effects of chelator degradation products on the partitioning of important radionuclides from the waste. Using NMR-active labels in the chelators, they will use a combinatorial approach of generating multiple chelator fragments in a single experiment and then determining which fragments have a negative effect on the separations chemistry. The successful completion of this goal will specifically identify the most problematic organic fragments in complexant-containing waste and provide the basis for developing successful treatment strategies for these wastes. This report summarizes work carried out at Los Alamos during the first 8 months of a 3-year project.'

  1. Intelligence: Real or artificial?

    Science.gov (United States)

    Schlinger, Henry D.

    1992-01-01

    Throughout the history of the artificial intelligence movement, researchers have strived to create computers that could simulate general human intelligence. This paper argues that workers in artificial intelligence have failed to achieve this goal because they adopted the wrong model of human behavior and intelligence, namely a cognitive essentialist model with origins in the traditional philosophies of natural intelligence. An analysis of the word “intelligence” suggests that it originally referred to behavior-environment relations and not to inferred internal structures and processes. It is concluded that if workers in artificial intelligence are to succeed in their general goal, then they must design machines that are adaptive, that is, that can learn. Thus, artificial intelligence researchers must discard their essentialist model of natural intelligence and adopt a selectionist model instead. Such a strategic change should lead them to the science of behavior analysis. PMID:22477051

  2. Artificial intelligence

    CERN Document Server

    Hunt, Earl B

    1975-01-01

    Artificial Intelligence provides information pertinent to the fundamental aspects of artificial intelligence. This book presents the basic mathematical and computational approaches to problems in the artificial intelligence field.Organized into four parts encompassing 16 chapters, this book begins with an overview of the various fields of artificial intelligence. This text then attempts to connect artificial intelligence problems to some of the notions of computability and abstract computing devices. Other chapters consider the general notion of computability, with focus on the interaction bet

  3. Radionuclides in the oceans inputs and inventories

    International Nuclear Information System (INIS)

    Guegueniat, P.; Germain, P.; Metivier, H.

    1996-01-01

    Ten years after Chernobyl, following the decision by France to end nuclear weapon testing in the Pacific ocean, after the end of the OECD-NEA Coordinated Research and Environmental Surveillance programme related to low-level waste dumping in the deep ocean, and one hundred years after the discovery of radioactivity, the IPSN wanted to compile and review the available information on artificial radioactivity levels in seas and oceans. International experts have been invited to present data on inputs and inventories of radionuclides in the marine environment, and to describe the evolution of radioactivity levels in water, sediments and living organisms. Different sources of radionuclides present in the aquatic environment are described: atmospheric fallout before and after Chernobyl, industrial wastes, dumped wastes and ships, nuclear ship accidents, river inputs, earth-sea atmospheric transfers and experimental sites for nuclear testing. Radioactivity levels due to these sources are dealt with at ocean (Atlantic, Pacific and Indian) and sea level (Channel, North Sea, Irish Sea, Mediterranean, Baltic, Black Sea and Arctic seas). These data collected in the present book give an up-to-date assessment of radionuclide distributions which will be very useful to address scientific and wider public concerns about radionuclides found in the aquatic environment. It gives many references useful to those who want to deepen their understanding of particular aspects of marine radioecology. (authors)

  4. Sources of anthropogenic radionuclides in the environment: a review

    International Nuclear Information System (INIS)

    Hu Qinhong; Weng Jianqing; Wang Jinsheng

    2010-01-01

    Studies of radionuclides in the environment have entered a new era with the renaissance of nuclear energy and associated fuel reprocessing, geological disposal of high-level nuclear wastes, and concerns about national security with respect to nuclear non-proliferation. This work presents an overview on sources of anthropogenic radionuclides in the environment, as well as a brief discussion of salient geochemical behavior of important radionuclides. We first discuss the following major anthropogenic sources and current developments that have lead, or could potentially contribute, to the radionuclide contamination of the environment: (1) nuclear weapons program; (2) nuclear weapons testing; (3) nuclear power plants; (4) uranium mining and milling; (5) commercial fuel reprocessing; (6) geological repository of high-level nuclear wastes that include radionuclides might be released in the future, and (7) nuclear accidents. Then, we briefly summarize the inventory of radionuclides 99 Tc and 129 I, as well as geochemical behavior for radionuclides 99 Tc, 129 I, and 237 Np, because of their complex geochemical behavior, long half-lives, and presumably high mobility in the environment; biogeochemical cycling and environment risk assessment must take into account speciation of these redox-sensitive radionuclides.

  5. The flow of radionuclides through the Canadian archipelago

    International Nuclear Information System (INIS)

    Ellis, K.; Smith, J.N.

    1999-01-01

    The transport of contaminants to the Canadian Arctic by air and in water and their concentration through the marine food web has lead to enhanced levels of contaminants in several foods of Canadian northern inhabitants. Artificial radionuclides in the marine water can be used to determine water circulation and to trace contaminant transport through the Canadian Archipelago

  6. Mechanical behavior of PMMA due to artificial aging by means of a xenon-test chamber; Comportamiento mecanico del polimetilmetacrilato sometido a envejecimiento artificial mediante camara xenotest

    Energy Technology Data Exchange (ETDEWEB)

    Colom, X.; Nogues, F.; Valldeperas, J.; Carrillo, F.; Gordillo, A.

    2001-07-01

    In this investigation, the mechanical behavior of poly(methylmethacrylate) due to aging in Xenon test chamber, using a xenon-arch lamp as alight radiation to simulate natural sun light has been studied. This work studies the mechanical properties (elongation at break, Young's modules, tensile strength and toughness) of PMMA samples exposed to different aging conditions (until 1560 h xenotest that correspond to 750 days exposure at natural light). The evolution of different mechanical properties characterizes the PMMA's process of degradation. (Author) 10 refs.

  7. Radionuclide Basics: Iodine

    Science.gov (United States)

    ... Search Radiation Protection Contact Us Share Radionuclide Basics: Iodine Iodine (chemical symbol I) is a chemical element. ... in the environment Iodine sources Iodine and health Iodine in the Environment All 37 isotopes of iodine ...

  8. Radionuclide Migration Program: strategy document

    International Nuclear Information System (INIS)

    1986-01-01

    The Radionuclide Migration Program (RNM) is composed of projects to obtain data that will define the hydrologic system on NTS and determine the radionuclides available for migration in that system. Specific objectives are: (1) determine the kinds and amounts of radionuclides available for migration in groundwater (Hydrologic Source Term); (2) determine regional and local hydrology; and (3) predict the direction and migration rates of radionuclides in groundwater and the radionuclide concentration at any given distance for the source

  9. Colloidal nature of radionuclides in seawater

    International Nuclear Information System (INIS)

    Feldman, I.

    1976-01-01

    There is considerable doubt that equilibrium calculations, i.e., employing solubility products and complex-ion stability constants, are valid for the submicro concentrations of radionuclides in seawater. The existence of radiocolloids should be expected in seawater. The great tendency of radiocolloids to adsorb onto finely divided hydrous oxides makes their formation of significance in seawater, especially for artificial radionuclides. The subject of radiocolloid formation is reviewed in this chapter. It is shown that the 226 Ra/ 230 Th/U relationship found in seawater can be explained from the fact that the tendencies of these elements to form radiocolloids in seawater should decrease in order thorium greater than radium much greater than uranium. This explanation is much simpler than the prevailing oceanographic one. The theories for radiocolloid formation are discussed. The recent theory of Jones and Healy for the adsorption of hydrolyzable metal ions onto hydrous oxides is reviewed briefly, and its relevance to radiocolloid formation is pointed out

  10. Colloidal nature of radionuclides in seawater

    International Nuclear Information System (INIS)

    Feldman, I.

    1976-01-01

    There is considerable doubt that equilibrium calculations, i.e., employing solubility products and complex-ion stability constants, are valid for the submicro concentrations of radionuclides in seawater. The existence of radiocolloids should be expected in seawater. The great tendency of radiocolloids to adsorb onto finely-divided hydrous oxides makes their formation of significance in seawater, especially for artificial radionuclides. The subject of radiocolloid formation is reviewed in this chapter. It is shown that the 226 Ra/ 230 Th/U relationship found in seawater can be explained from the fact that the tendencies of these elements to form radiocolloids in seawater should decrease in order thorium > radium much greater than uranium. This explanation is much simpler than the prevailing oceanographic one. The theories for radiocolloid formation are discussed. The recent theory of Jones and Healy for the adsorption of hydrolyzable metal ions onto hydrous oxides is reviewed briefly, and its relevance to radiocolloid formation is pointed out

  11. Effects of Duty Cycle, Current Frequency, and Current Density on Corrosion Behavior of the Plasma Electrolytic Oxidation Coatings on 6061 Al Alloy in Artificial Seawater

    Science.gov (United States)

    Vakili-Azghandi, Mojtaba; Fattah-alhosseini, Arash

    2017-10-01

    In this study, the effects of duty cycle, current frequency, and current density on corrosion behavior of the plasma electrolytic oxidation (PEO) coatings on 6061 Al alloy in artificial seawater (3.5 wt pct NaCl solution) were investigated. To serve this purpose, the electrical parameters of a unipolar pulsed current were applied during the PEO process on 6061 Al alloy in alkaline silicate electrolyte with and without Al2O3 nanoparticles. The coating morphology and microstructure were characterized by the scanning electron microscopy. The corrosion behavior and electrochemical response of the specimens treated by plasma electrolytic oxidation were analyzed by the electrochemical impedance spectroscopy and the potentiodynamic polarization in artificial seawater. It was found that PEO coatings formed in the presence of Al2O3 nanoparticle had lower porosity and exhibited better corrosion behavior compared with the coatings formed in the absence of Al2O3 nanoparticle in the structure. This can be attributed to the nanoparticles' incorporation and penetration through the PEO coatings. On the other hand, the decrease in the current density and increases in the duty cycle and frequency lead to further reduction of the nanoparticles' incorporation and distribution on the coating surface.

  12. The fate and importance of radionuclides produced in nuclear events

    International Nuclear Information System (INIS)

    Shore, B.; Anspaugh, L.; Chertok, R.; Gofman, J.; Harrison, F.; Heft, R.; Koranda, J.; Ng, Y.; Phelps, P.; Potter, G.; Tamplin, A.

    1969-01-01

    Some of the major program at the Bio-Medical Division concerned with the fate and importance of the fission products, the radionuclides induced in the device materials, the radionuclides induced in the environment surrounding the device, and the tritium produced in Plowshare cratering events will be discussed. These programs include (1) critical unknowns in predicting organ and body burdens from radionuclides produced in cratering events; (2) the analysis with a high-resolution solid state gamma ray spectrometer of radionuclides in complex biological and environmental samples; (3) the characterization of radioactive particles from cratering detonation; (4) the biological availability to beagles, pigs and goats of radionuclides in Plowshare debris; (5) the biological availability to aquatic animals of radionuclides in Plowshare and other nuclear debris and the biological turnover of critical nuclides in specific aquatic animals; (6) the biological availability of Plowshare and other nuclear debris radionuclides to dairy cows and the transplacental transport of debris radionuclides in the dairy cow; (7) the persistence and behavior of radionuclides, particularly tritium, at sites of Plowshare and other nuclear detonations; and (8) somatic effects of Low Dose Radiation: Chromosome studies. (author)

  13. Radionuclides in drinking water: the recent legislative requirements of the European Union

    International Nuclear Information System (INIS)

    Grande, Sveva; Risica, Serena

    2015-01-01

    In November 2013, a new EURATOM Directive was issued on the protection of public health from the radionuclide content in drinking water. After introducing the contents of the Directive, the paper analyses the hypotheses about drinking water ingestion adopted in documents of international and national organizations and the data obtained from national/regional surveys. Starting from the Directive’s parametric value for the Indicative Dose, some examples of derived activity concentrations of radionuclides in drinking water are reported for some age classes and three exposure situations, namely, (i) artificial radionuclides due to routine water release from nuclear power facilities, (ii) artificial radionuclides from nuclear medicine procedures, and (iii) naturally occurring radionuclides in drinking water or resulting from existing or past NORM industrial activities. (paper)

  14. Radionuclide migration as a function of mineralogy

    International Nuclear Information System (INIS)

    Triay, I.R.; Mitchell, A.J.; Ott, M.A.

    1991-01-01

    The migration of radionuclides is studies as a function of mineralogy utilizing batch sorption and column experiments. The transport behavior of alkaline, alkaline-earth, and transition metals, and actinide species is studies in pure mineral separates. The solid phases utilized for these investigations are silicates, alumino-silicates, carbonates, and metal oxides and oxyhydroxides. The results of this effort are utilized to aid in the elucidation of the dominant chemical mechanisms of radionuclide migration, the prediction of radionuclide transport in conditions similar to those expected at the proposed high-level nuclear waste repository at Yucca Mountain, Nevada, and the identification of materials that act as natural geological barriers or that can be utilized as strong sorbers in engineered barriers. 9 refs., 2 figs., 2 tabs

  15. Investigation on the development of measurement techniques, the behavior in the environment and the estimation of internal radiation dose by inhalation for some typical atmospheric radionuclides

    Energy Technology Data Exchange (ETDEWEB)

    Amano, Hikaru [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    1996-06-01

    Radionuclides in surface atmosphere on the earth are {sup 222}Rn, {sup 220}Rn and their short lived progeny, {sup 7}Be, {sup 85}Kr, {sup 3}H, {sup 14}C, {sup 137}Cs, {sup 90}Sr and so on. In this paper, among them, {sup 222}Rn, their short lived progeny ({sup 218}Po, {sup 214}Pb, {sup 214}Bi, {sup 214}Po), {sup 7}Be, {sup 3}H, and {sup 90}Sr are focused on as follows based on the experimental and observed results, 1. Development of their measurement techniques, 2. Analysis of their variation of atmospheric concentration with time and places, 3. Analysis of their interaction characteristics with surface environment including plants, 4. Estimation of internal radiation doses by inhalation of them. (author). 228 refs.

  16. Mass spectrometry of long-lived radionuclides

    International Nuclear Information System (INIS)

    Becker, Johanna Sabine.

    2003-01-01

    The capability of determining element concentrations at the trace and ultratrace level and isotope ratios is a main feature of inorganic mass spectrometry. The precise and accurate determination of isotope ratios of long-lived natural and artificial radionuclides is required, e.g. for their environmental monitoring and health control, for studying radionuclide migration, for age dating, for determining isotope ratios of radiogenic elements in the nuclear industry, for quality assurance and determination of the burn-up of fuel material in a nuclear power plant, for reprocessing plants, nuclear material accounting and radioactive waste control. Inorganic mass spectrometry, especially inductively coupled plasma mass spectrometry (ICP-MS) as the most important inorganic mass spectrometric technique today, possesses excellent sensitivity, precision and good accuracy for isotope ratio measurements and practically no restriction with respect to the ionization potential of the element investigated--therefore, thermal ionization mass spectrometry (TIMS), which has been used as the dominant analytical technique for precise isotope ratio measurements of long-lived radionuclides for many decades, is being replaced increasingly by ICP-MS. In the last few years instrumental progress in improving figures of merit for the determination of isotope ratio measurements of long-lived radionuclides in ICP-MS has been achieved by the application of a multiple ion collector device (MC-ICP-MS) and the introduction of the collision cell interface in order to dissociate disturbing argon-based molecular ions, to reduce the kinetic energy of ions and neutralize the disturbing noble gas ions (e.g. of 129 Xe + for the determination of 129 I). The review describes the state of the art and the progress of different inorganic mass spectrometric techniques such as ICP-MS, laser ablation ICP-MS vs. TIMS, glow discharge mass spectrometry, secondary ion mass spectrometry, resonance ionization mass

  17. Intelligence: Real or artificial?

    OpenAIRE

    Schlinger, Henry D.

    1992-01-01

    Throughout the history of the artificial intelligence movement, researchers have strived to create computers that could simulate general human intelligence. This paper argues that workers in artificial intelligence have failed to achieve this goal because they adopted the wrong model of human behavior and intelligence, namely a cognitive essentialist model with origins in the traditional philosophies of natural intelligence. An analysis of the word “intelligence” suggests that it originally r...

  18. Radioactivity: radionuclides in foods

    International Nuclear Information System (INIS)

    Simpson, R.E.; Baratta, E.J.; Jelinek, C.F.

    1977-01-01

    The results are summarized of the analysis for strontium-90, cesium-137, iodine-131, ruthenium-106, and potassium-40, a naturally occurring radionuclide, in samples of total diet and selected import commodities in the foods compliance program of the Food and Drug Administration. On the basis of the radionuclide intake guidelines established by the Federal Radiation Council (FRC), the low content of radionuclides found in the total diet samples for fiscal years 1973 and 1974 demonstrates the need for surveillance only at the present level. The low levels of radionuclides found in a limited number of edible imported commodities indicate that their contribution to the total diet would not increase the levels of these radionuclides above those recommended for only periodic surveillance by the FRC. The potassium levels, determined from potassium-40 activity, found in meats and fish agree with the value for normal muscle tissue for the reference man reported by the International Commission on Radiation Protection. Of the other commodities, nuts contained the highest levels, while sugar, beverages, and processed foods contained the lowest levels of potassium. Although cesium and potassium are chemical analogs with similar metabolic properties, because of their variable content in some leafy samples as a result of surface contamination, a correlation between cesium-137 levels and the cesium-137-to-potassium ratio was inconclusive

  19. Modeling the Effects of Cu Content and Deformation Variables on the High-Temperature Flow Behavior of Dilute Al-Fe-Si Alloys Using an Artificial Neural Network.

    Science.gov (United States)

    Shakiba, Mohammad; Parson, Nick; Chen, X-Grant

    2016-06-30

    The hot deformation behavior of Al-0.12Fe-0.1Si alloys with varied amounts of Cu (0.002-0.31 wt %) was investigated by uniaxial compression tests conducted at different temperatures (400 °C-550 °C) and strain rates (0.01-10 s -1 ). The results demonstrated that flow stress decreased with increasing deformation temperature and decreasing strain rate, while flow stress increased with increasing Cu content for all deformation conditions studied due to the solute drag effect. Based on the experimental data, an artificial neural network (ANN) model was developed to study the relationship between chemical composition, deformation variables and high-temperature flow behavior. A three-layer feed-forward back-propagation artificial neural network with 20 neurons in a hidden layer was established in this study. The input parameters were Cu content, temperature, strain rate and strain, while the flow stress was the output. The performance of the proposed model was evaluated using the K-fold cross-validation method. The results showed excellent generalization capability of the developed model. Sensitivity analysis indicated that the strain rate is the most important parameter, while the Cu content exhibited a modest but significant influence on the flow stress.

  20. Cyclic stress-strain behavior of polymeric nonwoven structures for the use as artificial leaflet material for transcatheter heart valve prostheses

    Directory of Open Access Journals (Sweden)

    Arbeiter Daniela

    2017-09-01

    Full Text Available Xenogenic leaflet material, bovine and porcine pericardium, is widely used for the fabrication of surgically implanted and transcatheter heart valve prostheses. As a biological material, long term durability of pericardium is limited due to calcification, degeneration and homogeneity. Therefore, polymeric materials represent a promising approach for a next generation of artificial heart valve leaflets with improved durability. Within the current study we analyzed the mechanical performance of polymeric structures based on elastomeric materials. Polymeric cast films were prepared and nonwovens were manufactured in an electrospinning process. Analysis of cyclic stress-strain behavior was performed, using a universal testing machine. The uniaxial cyclic tensile experiments of the elastomeric samples yielded a non-linear elastic response due to viscoelastic behavior with hysteresis. Equilibrium of stress-strain curves was found after a specific number of cycles, for cast films and nonwovens, respectively. In conclusion, preconditioning was found obligatory for the evaluation of the mechanical performance of polymeric materials for the use as artificial leaflet material for heart valve prostheses.

  1. Radionuclides in house dust

    CERN Document Server

    Fry, F A; Green, N; Hammond, D J

    1985-01-01

    Discharges of radionuclides from the British Nuclear Fuel plc (BNFL) reprocessing plant at Sellafield in Cumbria have led to elevated concentrations radionuclides in the local environment. The major routes of exposure of the public are kept under review by the appropriate Government departments and monitoring is carried out both by the departments and by BNFL itself. Recently, there has been increasing public concern about general environmental contamination resulting from the discharges and, in particular, about possible exposure of members of the public by routes not previously investigated in detail. One such postulated route of exposure that has attracted the interest of the public, the press and Parliament arises from the presence of radionuclides within houses. In view of this obvious and widespread concern, the Board has undertaken a sampling programme in a few communities in Cumbria to assess the radiological significance of this source of exposure. From the results of our study, we conclude that, alt...

  2. Transfer parameters of radionuclides in the marine environment

    International Nuclear Information System (INIS)

    1996-03-01

    To increase the accuracy of estimation of exposure dose by radionuclides in the marine, the informations of environmental parameter data in the marine were collected, arranged and discussed. The informations were discussed by 'a sectional committee of marine suspended solids and sediment'. The following problems were investigated and the studies were recorded in this report, clear explanation about the distribution factor (kd), the estimation method of kd, the fluctuating factor of kd data (properties of suspension and sediment, differences among the experimental methods), the physical and chemical behavior of radionuclides, sediment of radionuclides by means of sorption to the suspended particles in the marine, sorption of radionuclides into the marine soil (sediment), re-eluent of radionuclides sorpted in the marine soil (sediment), and relation between marine organism and marine suspended materials and sediment. (S.Y.)

  3. Radionuclide studies in impotence

    Energy Technology Data Exchange (ETDEWEB)

    Hilson, A.J.; Lewis, C.A. (St. Peter' s Hospitals, London (England))

    1991-04-01

    Impotence may be of physiological origin with causes including vascular or neurological pathology. Alternatively, it may be of psychogenic origin. Clinicians can distinguish between psychological and organic impotence by observing nocturnal penile tumescence. Non-radionuclide investigations for organic impotence include penile plethysmography or pulse Doppler analysis for arterial supply, cavernosometry for venous drainage, and biothesiometry or evoked potentials for neurological pathology. Radionuclide studies are primarily based on the use of technetium 99m-pertechnetate, 99mTc-red blood cells, or xenon 133 to study the blood flow, with or without pharmacological intervention, commonly papaverine. 26 references.

  4. Targeted Radionuclide Therapy

    International Nuclear Information System (INIS)

    Ersahin, Devrim; Doddamane, Indukala; Cheng, David

    2011-01-01

    Targeted radiotherapy is an evolving and promising modality of cancer treatment. The killing of cancer cells is achieved with the use of biological vectors and appropriate radionuclides. Among the many advantages of this approach are its selectiveness in delivering the radiation to the target, relatively less severe and infrequent side effects, and the possibility of assessing the uptake by the tumor prior to the therapy. Several different radiopharmaceuticals are currently being used by various administration routes and targeting mechanisms. This article aims to briefly review the current status of targeted radiotherapy as well as to outline the advantages and disadvantages of radionuclides used for this purpose

  5. Biological targeting of radionuclides

    International Nuclear Information System (INIS)

    Wheldon, T.E.; Glasgow Univ.

    1993-01-01

    Targeted radionuclide therapy in several forms has now been investigated in the clinic for more than 10 years. Despite some promising indications, targeted radiotherapy has not yet had a large impact on cancer therapy. Theoretical analysis shows that tumour cure would not often be expected using existing treatments. Addition of external-beam irradiation appears to be a robust strategy, which is appropriate in a wide range of situations. In future, many new agents will be made available by progress in molecular biology. However, integration of targeted radionuclide therapy with other modalities, especially radiotherapy, may still be required. (Author)

  6. Treatment with radionuclides

    International Nuclear Information System (INIS)

    Radeva, M.

    2000-01-01

    The application of nuclides for therapy is a noninvasive treatment modality, which is characterized by the selective delivery of the radiation dose to target tissues (tumors or organs). Radionuclide therapy provides an alternative to surgical or medical treatment for several benign disorders. Basically, it is disease (metabolic radionuclide therapy). On the same principle is based the nuclide therapy of any endocrine tumors. The paper presents several methods for determination of the dose in treatment of thyroid diseases. A data of the '1'3'1' I therapy of thyroid diseases at the Medical University of Sofia are shown

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

    International Nuclear Information System (INIS)

    Ballestra, S.; Lopez, J.J.; Gastaud, J.; Vas, D.; Noshkin, V.

    1991-08-01

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

  8. Radionuclides and agriculture

    International Nuclear Information System (INIS)

    Gasia, M.C.

    1987-01-01

    The pollution of agricultural ecosystems by radionuclides is reviewed. Examples are taken from the measurements performed in Belgium after the Chernobyl accident. Radioisotopes, however, can also play a useful role in agriculture. Their use as tracers or as ionizing radiation sources is described. (M.C.B.)

  9. Effects of educational intervention on nurses' knowledge, attitudes, and behavioral intentions toward supplying artificial nutrition and hydration to terminal cancer patients.

    Science.gov (United States)

    Ke, Li-Shan; Chiu, Tai-Yuan; Hu, Wen-Yu; Lo, Su-Shun

    2008-11-01

    This study aimed to investigate the effects of educational intervention on nurses' knowledge, attitudes, and behavioral intentions regarding supplying artificial nutrition and hydration (ANH) to terminal cancer patients. A quasi-experimental design was adopted. A structured questionnaire evaluated the effects of educational intervention. From April to June 2005, 88 nurses were enrolled in the gastroenterology, general surgery, and intensive care unit of Taipei Veterans General Hospital in Taiwan. The nurses were randomly assigned into experimental and control groups in equal numbers (44 nurses in each group). After the experimental and control groups completed the pretest, the experimental group participated in a 50-min lecture. Both groups received a post-test 2 weeks after the lecture. This study showed that prior to educational intervention, nurses have possessed experiences of ANH use in routine caring for terminal cancer patients. However, due to the lack of knowledge about supplying ANH to terminal cancer patients, the nurses trended toward the negative behavioral intention, although they realized the burdens of ANH in these patients. After educational intervention, mean scores of knowledge, attitudes and behavioral intentions of the experimental group increased significantly (z = -5.255, p 0.05). The educational intervention remarkably improved nurses' knowledge and attitudes regarding supplying terminal cancer patients with ANH. As for the changes in the behavioral intentions, it requires long-term moral and ethical training and communication. The results of this research emphasized the importance of educational interventions, which should be considered seriously in future reference nursing education program.

  10. In-vivo evaluation of the kinematic behavior of an artificial medial meniscus implant: A pilot study using open-MRI.

    Science.gov (United States)

    De Coninck, Tineke; Elsner, Jonathan J; Linder-Ganz, Eran; Cromheecke, Michiel; Shemesh, Maoz; Huysse, Wouter; Verdonk, René; Verstraete, Koenraad; Verdonk, Peter

    2014-09-01

    In this pilot study we wanted to evaluate the kinematics of a knee implanted with an artificial polycarbonate-urethane meniscus device, designed for medial meniscus replacement. The static kinematic behavior of the implant was compared to the natural medial meniscus of the non-operated knee. A second goal was to evaluate the motion pattern, the radial displacement and the deformation of the meniscal implant. Three patients with a polycarbonate-urethane implant were included in this prospective study. An open-MRI was used to track the location of the implant during static weight-bearing conditions, within a range of motion of 0° to 120° knee flexion. Knee kinematics were evaluated by measuring the tibiofemoral contact points and femoral roll-back. Meniscus measurements (both natural and artificial) included anterior-posterior meniscal movement, radial displacement, and meniscal height. No difference (P>0.05) was demonstrated in femoral roll-back and tibiofemoral contact points during knee flexion between the implanted and the non-operated knees. Meniscal measurements showed no significant difference in radial displacement and meniscal height (P>0.05) at all flexion angles, in both the implanted and non-operated knees. A significant difference (P ≤ 0.05) in anterior-posterior movement during flexion was observed between the two groups. In this pilot study, the artificial polycarbonate-urethane implant, indicated for medial meniscus replacement, had no influence on femoral roll-back and tibiofemoral contact points, thus suggesting that the joint maintains its static kinematic properties after implantation. Radial displacement and meniscal height were not different, but anterior-posterior movement was slightly different between the implant and the normal meniscus. Copyright © 2014 Elsevier Ltd. All rights reserved.

  11. Monitoring and classifying animal behavior using ZigBee-based mobile ad hoc wireless sensor networks and artificial neural networks

    DEFF Research Database (Denmark)

    S. Nadimi, Esmaeil; Jørgensen, Rasmus Nyholm; Blanes-Vidal, Victoria

    2012-01-01

    Animal welfare is an issue of great importance in modern food production systems. Because animal behavior provides reliable information about animal health and welfare, recent research has aimed at designing monitoring systems capable of measuring behavioral parameters and transforming them into ...

  12. Radionuclide cardiography in medical practice

    International Nuclear Information System (INIS)

    Strangfeld, D.; Mohnike, W.; Schmidt, J.; Heine, H.; Correns, H.J.

    1986-01-01

    This publication is a compendium on all aspects of radionuclide diagnostics concerning cardiovascular system diseases. Starting with introductory remarks on the control of cardiovascular diseases the contribution of radionuclide cardiology to functional cardiovascular diagnostics as well as pathophysiological and pathobiochemical aspects of radiocardiography are outlined. Radiopharmaceuticals used in radiocardiography, physical and technical problems in application of radionuclides and their measuring techniques are discussed. In individual chapters radionuclide ventriculography, myocardial scintiscanning, circulatory diagnostics, radionuclide diagnostics of arterial hypertension, of thrombosis and in vitro diagnostics of thrombophilia are treated in the framework of clinical medicine

  13. Radionuclide transfer from feed to camel milk.

    Science.gov (United States)

    Al-Masri, M S; Al-Hamwi, A; Amin, Y; Safieh, M B; Zarkawi, M; Soukouti, A; Dayyoub, R; Voigt, G; Fesenko, S

    2014-06-01

    The transfer of (137)Cs, (85)Sr, (131)I, (210)Po, (210)Pb and (238)U from feed to camel's milk was investigated in a pilot experiment with three lactating camels. For a period of 60 days, the animals were fed on spiked feed containing the studied radionuclides. They were subsequently returned to a contamination-free diet and monitored for another 90 days. The activity concentrations of (137)Cs, (85)Sr and (131)I in milk decreased with time and reached background levels after 20 days. Equilibrium transfer coefficients and biological half-lives were estimated and transfer coefficients were calculated as (8.1 ± 3.6) × 10(-4), (4.4 ± 1.6) × 10(-2), (7.8 ± 3.9) × 10(-4), (2.7 ± 3.5) × 10(-4), (1.8 ± 1.5) × 10(-4) and (7.0 ± 3.6) × 10(-3) d L(-1) for (85)Sr, (131)I, (137)Cs, (210)Po, (210)Pb and (238)U, respectively. The biological half-lives were estimated to be 6.4, 4.2, 8.9, and 53.3 days for (85)Sr, (131)I, (137)Cs, and (238)U, respectively. Estimates of the half-lives were based on a one component model: it was found that the half-life values measured for artificial radionuclides were slightly shorter than those for natural radionuclides. The data obtained in the study are the first published experimental data on radionuclide transfer to camel milk. Copyright © 2014 Elsevier Ltd. All rights reserved.

  14. Mobility of radionuclides in soil

    International Nuclear Information System (INIS)

    Gee, G.W.; Rai, D.; Serne, R.J.

    1983-01-01

    Recent public interest in nuclear power production and waste disposal has led to increased awareness and concern about the biological hazards of radionuclide cycling in soil. Various radionuclides found in soils are shown and can be seen to originate from numerous sources including: radioisotopes formed during earth genesis, cosmic irradiation, fallout from atmospheric testing, uranium mill tailings, phosphate mill wastes, nuclear and coal fired power plants, defense activities, medical, industrial and research use. The objectives of this review are to summarize the factors that affect radionuclide mobility in soil, including adsorption-desorption, precipitation-dissolution reactions for liquid phase radionuclides as well as the transport of gaseous radionuclides in soils. Areas where more information is needed are also discussed. The mobility of selected radionuclides including isotopes of Sr, Cs, Co, Tc, I, Se, Pu, Am, Np, and Rn are discussed in additional detail. Two brief examples of waste management systems to control radionuclide mobility are presented

  15. Radiation dosimetry for radionuclide therapy

    International Nuclear Information System (INIS)

    Kim, Eun Hee

    2001-01-01

    The radionuclide therapy is a protocol for tumor control by administering radionuclides as the cytotoxic agents. Radionuclides concentrated at the site of cancerous lesion are expected to kill the cancerous cells with minimal injury to the normal tissue. The efficacy of every radionuclide treatment can be evaluated by examining the toxicity to the lesion differentiated from that to the normal tissue. Radiation dosimerty is the procedure of quantitating the energy absorbed by target volumes of interest. Dosimetric information plays an indicator of the expected radiation damage and thus the therapeutic efficacy. This paper summarizes the dosimetric aspects in radionuclide therapy in terms of radionuclides of use, radionuclides of use, radiation dosimetry methodology and considerations for each treatment in practical use

  16. Uranium and Cesium sorption to bentonite colloids in high salinity and carbonate-rich environments: Implications for radionuclide transport

    Science.gov (United States)

    Tran, E. L.; Teutsch, N.; Klein-BenDavid, O.; Weisbrod, N.

    2017-12-01

    When radionuclides are leaked into the subsurface due to engineered waste disposal container failure, the ultimate barrier to migration of radionuclides into local aquifers is sorption to the surrounding rock matrix and sediments, which often includes a bentonite backfill. The extent of this sorption is dependent on pH, ionic strength, surface area availability, radionuclide concentration, surface mineral composition, and solution chemistry. Colloidal-sized bentonite particles eroded from the backfill have been shown to facilitate the transport of radionuclides sorbed to them away from their source. Thus, sorption of radionuclides such as uranium and cesium to bentonite surfaces can be both a mobilization or retardation factor. Though numerous studies have been conducted to-date on sorption of radionuclides under low ionic strength and carbonate-poor conditions, there has been little research conducted on the behavior of radionuclides in high salinities and carbonate rich conditions typical of aquifers in the vicinity of some potential nuclear repositories. This study attempts to characterize the sorption properties of U(VI) and Cs to bentonite colloids under these conditions using controlled batch experiments. Results indicated that U(VI) undergoes little to no sorption to bentonite colloids in a high-salinity (TDS= 9000 mg/L) artificial groundwater. This lack of sorption was attributed to the formation of CaUO2(CO3)22- and Ca2UO2(CO3)3 aqueous ions which stabilize the UO22+ ions in solution. In contrast, Cs exhibited greater sorption, the extent to which was influenced greatly by the matrix water's ionic strength and the colloid concentration used. Surprisingly, when both U and Cs were together, the presence of U(VI) in solution decreased Cs sorption, possibly due to the formation of stabilizing CaUO2(CO3)22- anions. The implications of this research are that rather than undergoing colloid-facilitated transport, U(VI) is expected to migrate similarly to a

  17. EBS Radionuclide Transport Abstraction

    International Nuclear Information System (INIS)

    J. Prouty

    2006-01-01

    The purpose of this report is to develop and analyze the engineered barrier system (EBS) radionuclide transport abstraction model, consistent with Level I and Level II model validation, as identified in Technical Work Plan for: Near-Field Environment and Transport: Engineered Barrier System: Radionuclide Transport Abstraction Model Report Integration (BSC 2005 [DIRS 173617]). The EBS radionuclide transport abstraction (or EBS RT Abstraction) is the conceptual model used in the total system performance assessment (TSPA) to determine the rate of radionuclide releases from the EBS to the unsaturated zone (UZ). The EBS RT Abstraction conceptual model consists of two main components: a flow model and a transport model. Both models are developed mathematically from first principles in order to show explicitly what assumptions, simplifications, and approximations are incorporated into the models used in the TSPA. The flow model defines the pathways for water flow in the EBS and specifies how the flow rate is computed in each pathway. Input to this model includes the seepage flux into a drift. The seepage flux is potentially split by the drip shield, with some (or all) of the flux being diverted by the drip shield and some passing through breaches in the drip shield that might result from corrosion or seismic damage. The flux through drip shield breaches is potentially split by the waste package, with some (or all) of the flux being diverted by the waste package and some passing through waste package breaches that might result from corrosion or seismic damage. Neither the drip shield nor the waste package survives an igneous intrusion, so the flux splitting submodel is not used in the igneous scenario class. The flow model is validated in an independent model validation technical review. The drip shield and waste package flux splitting algorithms are developed and validated using experimental data. The transport model considers advective transport and diffusive transport

  18. EBS Radionuclide Transport Abstraction

    Energy Technology Data Exchange (ETDEWEB)

    J. Prouty

    2006-07-14

    The purpose of this report is to develop and analyze the engineered barrier system (EBS) radionuclide transport abstraction model, consistent with Level I and Level II model validation, as identified in Technical Work Plan for: Near-Field Environment and Transport: Engineered Barrier System: Radionuclide Transport Abstraction Model Report Integration (BSC 2005 [DIRS 173617]). The EBS radionuclide transport abstraction (or EBS RT Abstraction) is the conceptual model used in the total system performance assessment (TSPA) to determine the rate of radionuclide releases from the EBS to the unsaturated zone (UZ). The EBS RT Abstraction conceptual model consists of two main components: a flow model and a transport model. Both models are developed mathematically from first principles in order to show explicitly what assumptions, simplifications, and approximations are incorporated into the models used in the TSPA. The flow model defines the pathways for water flow in the EBS and specifies how the flow rate is computed in each pathway. Input to this model includes the seepage flux into a drift. The seepage flux is potentially split by the drip shield, with some (or all) of the flux being diverted by the drip shield and some passing through breaches in the drip shield that might result from corrosion or seismic damage. The flux through drip shield breaches is potentially split by the waste package, with some (or all) of the flux being diverted by the waste package and some passing through waste package breaches that might result from corrosion or seismic damage. Neither the drip shield nor the waste package survives an igneous intrusion, so the flux splitting submodel is not used in the igneous scenario class. The flow model is validated in an independent model validation technical review. The drip shield and waste package flux splitting algorithms are developed and validated using experimental data. The transport model considers advective transport and diffusive transport

  19. Radionuclides in pharmaceutical researches

    International Nuclear Information System (INIS)

    Khujaev, S.

    2005-01-01

    Full text: The development of modern stage of nuclear medicine is characterized by the increasing role of methods using radionuclides. Radioactive nuclides used in nuclear medicine may be divided into 2 groups. Radionuclides used for diagnostic researches and radionuclides used for therapeutic purposes. These two directions are considered to be the main ones in usage of radionuclides in medicine. However there is one more direction in the research of new medical products where it is possible to use radionuclides to study their pharmacological kinetics. In these researches radionuclide is applied as a radioactive label at the stage of studying pharmacological kinetics of a new medical product. In Institute of Nuclear Physics AS RUz the works are being carried out in the recent years focused on studying pharmacology of some new medical preparations, which are synthesized in Tashkent Pharmaceutical Institute. Syntheses these preparations are based on use microelements. Its compounds are possessed expressed biological activity and be of great importance in the pharmaceutical science of Uzbekistan. Introducing a radioisotope at the stage of synthesis carried out reception of labeled connections of all preparations. The output of the final product reached the yield of no less than 80 % in all cases of synthesis. This work presents the results of research on synthesis and study of pharmacology of radioactively labeled preparations - Piracin, labeled by radioisotope 69m Zn; Pheramed, labeled by radioisotope 59 Fe; Cobavit, labeled by radioisotope 57 Co; VUC, labeled by radioisotope 57 Co, CO-101, labeled by radioisotope 57 Co. Received radioisotope - labeled compounds of medical preparations were used in the study of their pharmacological kinetics on experimental rats. In all cases, preliminary irradiation of corresponding nuclear targets in the nuclear reactor and cyclotron, radiochemical procedures on separation, purification and concentration oi radioactive isotopes

  20. Initial Radionuclide Inventories

    Energy Technology Data Exchange (ETDEWEB)

    H. Miller

    2004-09-19

    The purpose of this analysis is to provide an initial radionuclide inventory (in grams per waste package) and associated uncertainty distributions for use in the Total System Performance Assessment for the License Application (TSPA-LA) in support of the license application for the repository at Yucca Mountain, Nevada. This document is intended for use in postclosure analysis only. Bounding waste stream information and data were collected that capture probable limits. For commercially generated waste, this analysis considers alternative waste stream projections to bound the characteristics of wastes likely to be encountered using arrival scenarios that potentially impact the commercial spent nuclear fuel (CSNF) waste stream. For TSPA-LA, this radionuclide inventory analysis considers U.S. Department of Energy (DOE) high-level radioactive waste (DHLW) glass and two types of spent nuclear fuel (SNF): CSNF and DOE-owned (DSNF). These wastes are placed in two groups of waste packages: the CSNF waste package and the codisposal waste package (CDSP), which are designated to contain DHLW glass and DSNF, or DHLW glass only. The radionuclide inventory for naval SNF is provided separately in the classified ''Naval Nuclear Propulsion Program Technical Support Document'' for the License Application. As noted previously, the radionuclide inventory data presented here is intended only for TSPA-LA postclosure calculations. It is not applicable to preclosure safety calculations. Safe storage, transportation, and ultimate disposal of these wastes require safety analyses to support the design and licensing of repository equipment and facilities. These analyses will require radionuclide inventories to represent the radioactive source term that must be accommodated during handling, storage and disposition of these wastes. This analysis uses the best available information to identify the radionuclide inventory that is expected at the last year of last emplacement

  1. EBS Radionuclide Transport Abstraction

    International Nuclear Information System (INIS)

    Schreiner, R.

    2001-01-01

    The purpose of this work is to develop the Engineered Barrier System (EBS) radionuclide transport abstraction model, as directed by a written development plan (CRWMS M and O 1999a). This abstraction is the conceptual model that will be used to determine the rate of release of radionuclides from the EBS to the unsaturated zone (UZ) in the total system performance assessment-license application (TSPA-LA). In particular, this model will be used to quantify the time-dependent radionuclide releases from a failed waste package (WP) and their subsequent transport through the EBS to the emplacement drift wall/UZ interface. The development of this conceptual model will allow Performance Assessment Operations (PAO) and its Engineered Barrier Performance Department to provide a more detailed and complete EBS flow and transport abstraction. The results from this conceptual model will allow PA0 to address portions of the key technical issues (KTIs) presented in three NRC Issue Resolution Status Reports (IRSRs): (1) the Evolution of the Near-Field Environment (ENFE), Revision 2 (NRC 1999a), (2) the Container Life and Source Term (CLST), Revision 2 (NRC 1999b), and (3) the Thermal Effects on Flow (TEF), Revision 1 (NRC 1998). The conceptual model for flow and transport in the EBS will be referred to as the ''EBS RT Abstraction'' in this analysis/modeling report (AMR). The scope of this abstraction and report is limited to flow and transport processes. More specifically, this AMR does not discuss elements of the TSPA-SR and TSPA-LA that relate to the EBS but are discussed in other AMRs. These elements include corrosion processes, radionuclide solubility limits, waste form dissolution rates and concentrations of colloidal particles that are generally represented as boundary conditions or input parameters for the EBS RT Abstraction. In effect, this AMR provides the algorithms for transporting radionuclides using the flow geometry and radionuclide concentrations determined by other

  2. Artificial Consciousness or Artificial Intelligence

    OpenAIRE

    Spanache Florin

    2017-01-01

    Artificial intelligence is a tool designed by people for the gratification of their own creative ego, so we can not confuse conscience with intelligence and not even intelligence in its human representation with conscience. They are all different concepts and they have different uses. Philosophically, there are differences between autonomous people and automatic artificial intelligence. This is the difference between intelligence and artificial intelligence, autonomous versus a...

  3. Radionuclide migration in groundwater. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Fruchter, J.S.; Cowan, C.E.; Robertson, D.E.; Girvin, D.C.; Jenne, E.A.; Toste, A.P.; Abel, K.H.

    1985-03-01

    For the past several years, data on radionuclide migration in groundwater at a low-level disposal site were collected. Most of the radionuclides were removed in the disposal basin and trench by either precipitation or adsorption mechanisms. However, three radionuclides /sup 60/Co, /sup 106/Ru, and /sup 125/Sb showed somewhat greater than expected mobility. The elements of these three isotopes were found to be in either anionic or nonionic charge-forms. Complexes with both natural and man-made organics were implicated in the increased mobility, particularly in the case of /sup 60/Co. Characterization studies of the organic fraction were performed. Ruthenium-103, /sup 60/Co, and /sup 125/Sb were found to be associated with the higher molecular weight organics, particularly humic and fulvic acids with molecular weights greater than 1000. Studies were also performed that proved the hypothesis that the adsorption behavior of /sup 235/Np on soils of the site is dominated by adsorption on iron hydroxide. Finally, geochemical modeling of the chemical and charge form data showed the groundwater to be in equilibrium with several solids that could be important in controlling the concentrations of trace elments and radionuclides. 47 references, 14 figures, 3 tables.

  4. Contamination of soil and food with radionuclides from Chernobyl

    International Nuclear Information System (INIS)

    Bikit, I.; Slivka, J.; Veskovic, M.; Conkic, Lj.; Krmar, M.

    2004-01-01

    The results of systematic gamma spectroscopic analyses of fission products performed on the territory of SAP Vojvodina after the Chernobyl accident are presented. Samples of soil grass and food were periodically taken at 5 representative locations and the regions of highest activity concentration are identified on the basis of the results obtained. In the controlled chain soil-plants (feeds)-cow's (milk) on three characteristic locations (soil with different physico-chemical and mechanical properties) the activity concentration of fission radionuclides was determined and transfer factors for soil-plants; feed-milk were calculated. At the territory of hunting sites of SAP Vojvodina, artificial radionuclides were determined in meat and bones of fallow-deer, deer, boar and wild hare; and the highest content of radionuclides was found in meat and bones of boar. (author)

  5. Long-lived radionuclides in the marine environment of Thailand

    International Nuclear Information System (INIS)

    Mahapanyawong, S.; Sonsuk, M.; Polphong, P.; Milintawisamai, M.; Panyatipsakul, Y.

    1992-01-01

    Natural and artificial radionuclides in the environment of the Gulf of Thailand were studied during 1989-1991. In the study, surface water, sediment at 5 locations between latitudes 9 degree 28 minute N and 13 degree 15 minute N longitudes 100 degree 35 minute E. and 5 species of marine biota were collected in 1989. In 1990 and 1991, 9 and 7 species of marine biota were collected from the Gulf of Thailand and the Andaman Sea respectively. These samples were prepared and analyzed for gamma-emitting radionuclides as well as some beta and alpha-emitting radionuclides such as C-14, Sr-90, Pu-239,240, Po-210 etc. The results indicate the present status of radioactivity level of the environment of the gulf and the sea

  6. Long-lived radionuclides in the marine environment of Thailand

    International Nuclear Information System (INIS)

    Mahapanyawong, S.; Sonsuk, M.; Polphong, P.; Milintawisamai, M.; Panyatipsakul, Y.

    1992-01-01

    Natural and artificial radionuclides in the environment of the Gulf of Thailand were studied during 1989-1991. In the study, surface water, sediment at 5 locations between latitudes 9 0 28' N and 13 0 15' N longitudes 100 0 35' E. and 5 species of marine biota were collected in 1989. In 1990 and 1991, 9 and 7 species of marine biota were collected from the Gulf of Thailand and the Andaman Sea respectively. These samples were prepared and analyzed for gamma-emitting radionuclides as well as some beta and alpha-emitting radionuclides such as C 14 , Sr 90 , Pu 239,240 , Po 210 etc. The results indicate the present status of radioactivity level of the environment of the gulf and the sea

  7. Fukushima Daiichi Radionuclide Inventories

    Energy Technology Data Exchange (ETDEWEB)

    Cardoni, Jeffrey N. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Jankovsky, Zachary Kyle [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2016-09-01

    Radionuclide inventories are generated to permit detailed analyses of the Fukushima Daiichi meltdowns. This is necessary information for severe accident calculations, dose calculations, and source term and consequence analyses. Inventories are calculated using SCALE6 and compared to values predicted by international researchers supporting the OECD/NEA's Benchmark Study on the Accident at Fukushima Daiichi Nuclear Power Station (BSAF). Both sets of inventory information are acceptable for best-estimate analyses of the Fukushima reactors. Consistent nuclear information for severe accident codes, including radionuclide class masses and core decay powers, are also derived from the SCALE6 analyses. Key nuclide activity ratios are calculated as functions of burnup and nuclear data in order to explore the utility for nuclear forensics and support future decommissioning efforts.

  8. Mercury and radionuclides in sediments of the Kastela Bay (Croatia) - evaluation of the sediment pollution history

    Energy Technology Data Exchange (ETDEWEB)

    Mikac, N.; Foucher, D.; Kwokal, Z.; Barisic, D. [Rudjer Boskovic Institute, Zagreb (Croatia). Division of Marine & Environmental Research

    2006-03-15

    Mercury and radionuclides (natural U and its decay series products and artificial (Cs-137) were measured in sediments of the Kastela Bay (eastern Adriatic coast) in the vicinity of a former chloralkali plant. The depth distributions of radionuclides and mercury revealed that sediments in front of the factory represent a mixture of natural sediment and coal ash originating from the coal used in the factory power plant. Based on this data, the hypothesis that the coal ash from the factory power plant was dumped into the sea was confirmed, and it was estimated (from Cs-137 depth profile) that the dumping happened between 1986 and 1991. Data on the artificial radionuclide Cs-137 was shown to be very useful for evaluation of the sediment pollution history even in such very disturbed sediments. Future monitoring of mercury pollution and radionuclides in the Kastela Bay is suggested.

  9. Radionuclide co-precipitation

    International Nuclear Information System (INIS)

    Bruno, J.; Sandino, A.

    1987-12-01

    The thermodynamic and kinetic behaviour of the minor components of the spent fuel matrix has been theoretically and experimentally investigated. Two different situations have been studied: Part I, the near field scenario, where the release and migration of the minor components is dependent on the solubility behaviour of UO 2 (s); Part II, the far field, where the solubility and transport of the radionuclides is related to the major geochemical processes occurring. (orig.)

  10. Ethical Artificial Intelligence

    OpenAIRE

    Hibbard, Bill

    2014-01-01

    This book-length article combines several peer reviewed papers and new material to analyze the issues of ethical artificial intelligence (AI). The behavior of future AI systems can be described by mathematical equations, which are adapted to analyze possible unintended AI behaviors and ways that AI designs can avoid them. This article makes the case for utility-maximizing agents and for avoiding infinite sets in agent definitions. It shows how to avoid agent self-delusion using model-based ut...

  11. Radionuclide therapy beyond radioiodine.

    Science.gov (United States)

    Gabriel, Michael

    2012-10-01

    For decades, Iodine-131 has been used for the treatment of patients with thyroid cancer. In recent years, increasingly, other radiopharmaceuticals are in clinical use in the treatment of various malignant diseases. Although in principle these therapies-as in all applications of radionuclides-special radiation protection measures are required, a separate nuclear medicine therapy department is not necessary in many cases due to the lower or lack of gamma radiation. In the following article, four different radionuclide therapies are more closely presented which are emerging in the last years. One of them is the "Peptide Receptor Radionuclide Therapy," the so-called PRRT in which radiolabeled somatostatin (SST)-receptor(R) ligands are used in patients with neuroendocrine tumors. On the basis of radiolabeled antibodies against CD20-positive cells, the so-called radioimmunotherapy is used in the treatment of certain forms of malignant lymphoma. In primary or secondary liver tumors, the (90)Y-labeled particles can be administered. Last but not the least, the palliative approach of bone-seeking radiopharmaceuticals is noted in patients with painful bone metastases.

  12. Radionuclide therapy of diseases

    International Nuclear Information System (INIS)

    Endo, Keigo

    1998-01-01

    Radionuclide therapy has a long history of more than 50 years. Radioiodine (I-131) is specifically taken up by the thyroid and has been still used for the therapy of Graves' disease and thyroid cancer. In the western country, I-131 is the first choice of the therapy of Graves' disease and it is well known that Mr. Geroge Bush, the former president of the United States, was suffered from Graves' disease and treated with I-131. I-131 therapy is cheap, safe, effective, but little adverse effects. On the contrary, in Japan I-131 therapy is less frequently used than the anti-thyroid drugs due to the national sentiments of allergy to radionuclides, and the strict regulation by the government. Bone pain is commonly seen in patients with bone metastasis, which occurs in prostate, breast and lung cancers. Strontium-89 is an effective treatment of bone pain palliation and widely used in the western countries. In Japan clinical use of strontium-89 is planned to be approved by this coming summer on the out-patients basis. Still we have many problems for the radionuclide therapy of diseases, although it is very useful method of treatment. (author)

  13. Radionuclides in terrestrial ecosystems

    International Nuclear Information System (INIS)

    Howard, B.J.; Kennedy, V.H.; Nelson, A.

    1983-06-01

    A bibliographical database has been developed to provide quick access to research and background literature in the field of radioecology. This is a development of an earlier database described by Nelson (Bocock 1981). ITE's particular fields of interest have led to a subject bias in the bibliography towards studies in Cumbria, especially those concerned with radionuclides originating from the reprocessing plant at Sellafield, and towards ecological research studies that are complementary to radionuclide studies. Other subjects covered, include the chemistry of radionuclides, budgets and transfers within ecosystems and techniques for the analysis of environmental samples. ITE's research objectives have led to the establishment of a specialized database which is intended to complement rather than compete with the large international databases made available by suppliers such as IRS-DIALTECH or DIALOG. Currently the database holds about 1900 references which are stored on a 2 1/2 megabyte hard disk on a Digital PDP11/34 computer operating under a time shared system. The references follow a standard format. (author)

  14. Radionuclides in thyroid cancer

    International Nuclear Information System (INIS)

    Mahadev, V.

    1980-01-01

    The three main areas of application of radionuclides in thyroid disease will be reviewed. Firstly thyroid radionuclide imaging in thyroid swellings, in relationship to lumps in the neck and ectopic thyroid tissue such as retrosternal goitre, and lingual goitre will be described. Future developments in the field including tomographic scanning, using the coded aperture method, and fluorescent scans and ultrasound are reviewed. The second area of application is the assessment and evaluation of thyroid function and the therapy of Grave's Disease and Plummer's Disease using radioiodine. The importance of careful collection of the line of treatment, results of treatment locally and the follow-up of patients after radioiodine therapy will be described. The third area of application is in the diagnosis and therapy of thyroid cancer. Investigation of thyroid swelling, and the diagnosis of functioning metastases are reported. The therapeutic iodine scan as the sole evidence of functioning metastatic involvement is recorded. Histological thyroid cancer appears to be increasingly encountered in clinical practice and the plan of management in relation to choice of cases for therapeutic scanning is discussed with case reports. Lastly the role of whole body scanning in relationship to biochemical markers is compared. In the changing field of nuclear medicine radionuclide applications in thyroid disease have remained pre-eminent and this is an attempt to reassess its role in the light of newer developments and local experience in the Institute of Radiotherapy, Oncology and Nuclear Medicine. (author)

  15. Report on the intercomparison run IAEA-308 radionuclides in seaweed mixture

    International Nuclear Information System (INIS)

    Ballestra, S.; Vas, D.; Lopez, J.J.; Noshkin, V.

    1989-12-01

    The results of an intercomparison exercise on a sample of mixed seaweeds from the Mediterranean Sea, IAEA-308, designed for the determination of artificial and natural radionuclide levels, are reported. The data from 67 laboratories representing 33 countries have been evaluated. The recommended median values, with confidence intervals, for the most frequently measured radionuclides 106 Ru, 110m Ag, 134 Cs, 137 Cs, 238 Pu, 239+240 Pu, 241 Am, 40 K, 210 Pb and 228 Th are given. Refs and tabs

  16. Behaviors of protective bank and reclaimed ground of artificial island type nuclear power station at the time of earthquakes

    International Nuclear Information System (INIS)

    Ishikawa, Hiroyuki; Takeda, Tomoyoshi

    1997-01-01

    The protective banks arranged around an artificial island type nuclear power station and the reclaimed ground behind them are the important structures for ensuring the safety of nuclear reactor facilities and others, therefore, the establishment of the technology for evaluating their aseismatic safety becomes a subject. In this research, in order to grasp the change of ground characteristics at the time of the occurrence of liquefaction and the dynamic interaction of structures and reclaimed ground, caisson type protective banks and the ground behind them were modeled, and the centrifugal loading model experiment was carried out. Next, by the FEM analysis using effective stress method, the numerical simulation of this experiment was performed, and it was shown that this analysis method is the effective technique for evaluating the displacement of protective banks, and the liquefaction and the residual subsidence of ground. The experimental method and the analysis of the experimental results of the model vibration experiment are reported. The analysis technique using the effective stress analysis code STADAS is explained. The numerical simulation of the experimental results is reported on the analysis model, the values of the properties used and the results. (K.I.)

  17. Effect of pH and fluoride on behavior of dental ZrO{sub 2} ceramics in artificial saliva

    Energy Technology Data Exchange (ETDEWEB)

    Mukaeda, L.E.; Robin, A.; Santos, C.; Taguchi, S.P.; Borges Junior, L.A., E-mail: luizamukaeda@gmail.com, E-mail: alain@demar.eel.usp.br, E-mail: claudinei@demar.eel.usp.br, E-mail: simone@demar.eel.usp.br, E-mail: borges.jr@itelefonica.com.br [Universidade de Sao Paulo (EEL/DEMAR/USP), Lorena, SP (Brazil). Escola de Engenharia; Machado, J.P.B., E-mail: joaopaulo@las.inpe.br [Instituto Nacional de Pesquisas Espaciais (INPE), Sao Jose dos Campos, SP (Brazil)

    2009-07-01

    A considerable increase in the ceramic products demand occurred due to the evolution of dental restoration techniques and these materials must resist to the complex mouth environment. The pH of saliva can decrease significantly due to the ingestion of acidic foods and beverages and mainly due to reactions occurring during bacteria metabolism that lead to the formation of organic acids. Fluorides are also present in the mouth since fluorides are usually added in drinking water, mouth washes, tooth pastes and gels for the prevention of plaque and caries formation. The combination of low pH and presence of fluorides can lead to the formation of HF and HF{sub 2}{sup -} which are detrimental to metallic and probably to ceramic devices. In this work, commercial blocks of ZrO{sub 2} ceramics (ProtMat Materiais Avancados® and Ivoclar®) were immersed in Fusayama artificial saliva of different pHs and fluoride concentrations. The properties of the as-produced ceramics (crystalline phases (XRD), microstructure (SEM), roughness (3D surface topography AFM) and mechanical resistance - Vickers hardness (Hv) and fracture toughness (KIC) were evaluated. Some of these properties were also determined after the immersion tests as well as the mass variation of the samples in order to evaluate the resistance of these ZrO{sub 2} ceramics to degradation under these conditions. (author)

  18. Effect of pH and fluoride on behavior of dental ZrO2 ceramics in artificial saliva

    International Nuclear Information System (INIS)

    Mukaeda, L.E.; Robin, A.; Santos, C.; Taguchi, S.P.; Borges Junior, L.A.

    2009-01-01

    A considerable increase in the ceramic products demand occurred due to the evolution of dental restoration techniques and these materials must resist to the complex mouth environment. The pH of saliva can decrease significantly due to the ingestion of acidic foods and beverages and mainly due to reactions occurring during bacteria metabolism that lead to the formation of organic acids. Fluorides are also present in the mouth since fluorides are usually added in drinking water, mouth washes, tooth pastes and gels for the prevention of plaque and caries formation. The combination of low pH and presence of fluorides can lead to the formation of HF and HF 2 - which are detrimental to metallic and probably to ceramic devices. In this work, commercial blocks of ZrO 2 ceramics (ProtMat Materiais Avancados® and Ivoclar®) were immersed in Fusayama artificial saliva of different pHs and fluoride concentrations. The properties of the as-produced ceramics (crystalline phases (XRD), microstructure (SEM), roughness (3D surface topography AFM) and mechanical resistance - Vickers hardness (Hv) and fracture toughness (KIC) were evaluated. Some of these properties were also determined after the immersion tests as well as the mass variation of the samples in order to evaluate the resistance of these ZrO 2 ceramics to degradation under these conditions. (author)

  19. A dynamic artificial gastrointestinal system for studying the behavior of orally administered drug dosage forms under various physiological conditions

    NARCIS (Netherlands)

    Blanquet, S.; Zeijdner, E.; Beyssac, E.; Meunier, J.-P.; Denis, S.; Havenaar, R.; Alric, M.

    2004-01-01

    Purpose. The purpose of this study was to demonstrate the potential of a dynamic, multicompartmental in vitro system simulating the human stomach and small intestine (TIM-1) for studying the behavior of oral drug dosage forms under various physiological gastrointestinal conditions. Methods. Two

  20. Artificial intelligence

    CERN Document Server

    Ennals, J R

    1987-01-01

    Artificial Intelligence: State of the Art Report is a two-part report consisting of the invited papers and the analysis. The editor first gives an introduction to the invited papers before presenting each paper and the analysis, and then concludes with the list of references related to the study. The invited papers explore the various aspects of artificial intelligence. The analysis part assesses the major advances in artificial intelligence and provides a balanced analysis of the state of the art in this field. The Bibliography compiles the most important published material on the subject of

  1. Tumor Immunotargeting Using Innovative Radionuclides

    OpenAIRE

    Françoise Kraeber-Bodéré; Caroline Rousseau; Caroline Bodet-Milin; Cédric Mathieu; François Guérard; Eric Frampas; Thomas Carlier; Nicolas Chouin; Ferid Haddad; Jean-François Chatal; Alain Faivre-Chauvet; Michel Chérel; Jacques Barbet

    2015-01-01

    This paper reviews some aspects and recent developments in the use of antibodies to target radionuclides for tumor imaging and therapy. While radiolabeled antibodies have been considered for many years in this context, only a few have reached the level of routine clinical use. However, alternative radionuclides, with more appropriate physical properties, such as lutetium-177 or copper-67, as well as alpha-emitting radionuclides, including astatine-211, bismuth-213, actinium-225, and others a...

  2. Assessment of radionuclide contents in food in Hong Kong

    International Nuclear Information System (INIS)

    Yu, K.N.; Mao, S.Y.

    1999-01-01

    Baseline values of concentrations of the natural radionuclides ( 238 U, 226 Ra, 228 Ra/ 232 Th, 210 Pb) and artificial radionuclides ( 137 Cs, 60 Co) in food and drinks (tap water, milk, and water-based drinks) were determined by gamma spectroscopy. All food and drinks were found to contain detectable 40 K contents: 0.1 to 160 Bq Kg -1 for food and 0.006 to 61 Bq L -1 for drinks. Most of the other natural radionuclides in solid food were found to have contents below the minimum detectable activities (MDA). More samples in the leafy vegetable, tomato, carrot and potato categories contained detectable amounts of 228 Ra than the meat, cereal, and fish categories, with concentrations up to 1.2 Bq kg -1 for the former categories and 0.35 Bq kg -1 for the latter categories. The 238 U and 226 Ra radionuclides were detectable in most of the water-based drink samples, and the 228 Ra and 210 Pb radionuclides were detectable in fewer water-based drink samples. The 137 Cs contents in solid food were detectable in most of the solid food samples (reaching 0.59 Bq kg -1 ), but in drinks the 137 Cs contents were very low and normally lower than the MDA values. Nearly all the 60 Co contents in food and drinks were below the MDA values and their contents were below those of 137 Cs

  3. Natural radionuclides in soils from Sao Paulo State cerrado forest

    Energy Technology Data Exchange (ETDEWEB)

    Miranda, Marcia V.F.E.S.; Farias, Emerson E.G. de; Cantinha, Rebeca S.; Franca, Elvis J. de, E-mail: mvaleria@cnen.gov.br, E-mail: emersonemiliano@yahoo.com.br, E-mail: rebecanuclear@gmail.com, E-mail: ejfranca@cnen.gov.br [Centro Regional de Ciencias Nucleares do Nordeste (CRCN-NE/CNEN-PE), Recife, PE (Brazil)

    2015-07-01

    Considering the long life history, forests should be preferentially evaluated for the monitoring of radionuclides, mainly artificial radioisotopes. However, little is known about nuclides from Uranium and Thorium series, as well as, K-40, in soils from the Sao Paulo State forests. Soils are the main reservoir of natural radionuclides for vegetation, thereby deserving attention. Taking into account the advantages of High-Resolution Gamma-ray Spectrometry (HRGS), diverse radionuclides can be quantified simultaneously. In this work natural radionuclides in soils from the Estacao Ecologica de Assis were evaluated by HRGS. Samples of 0-10 cm depth were collected under crown projection of most abundant tree species of long-term plots installed within the Estacao Ecologica de Assis, Sao Paulo State, Brazil. After drying and milling until 0.5 mm particle size, test portions of 30 g were transferred to polypropylene vials, sealed with silicone and kept under controlled conditions until 30 days to achieve secular equilibrium. A group of gamma-ray spectrometers was used to analyze about 27 samples by 80,000 seconds. Activity concentrations of Pb-214, Ac-228 and K-40 and their respective expanded analytical uncertainties at the 95% confidence level were calculated by Genie software from Canberra. Abnormal values were not detected for radionuclides in soils samples, however K-40 activity concentrations changed considerably due to the mineral cycling, in which K and, consequently K-40, is mainly stocked in vegetation in spite of soils. (author)

  4. Concentration of some radionuclides in Moringa Oliefera plant

    International Nuclear Information System (INIS)

    Abd elbagi, W. K. A.

    2013-07-01

    This study has been conducted to determine the radioactivity concentration of naturally occurring radionuclides 228 U, 232 Th, and 40 K in samples of Moringaoliefera plants in Khartoum Bahry Elsamrab by using γ ray spectrometry sodium iodide detector and high purity germanium detector. A total of 30 samples, 10 samples from leaves, 10 samples from seeds and 10 samples from soil of samples have been collected. For leaves the radionuclide activity concentrations in samples analyzed with the mean of 2767.266±78.6741 Bq kg - 1 for 238 U, 3486.817±80.98811 Bq kg - 1 for 238 Th and 2273.386±54.152 Bq kg - 1 for 40 K. For seeds the radionuclide activity concentration in samples analyzed with the mean of 2839.224±72.6016 Bq kg - 1 for 238 U, 2844.372±78.74919 Bq kg - 1 for 2 38T h and 2377.005±91.8838 Bq kg - 1 for 40 K. No trace of artificial radionuclide has been determined in all the samples. The effective dose due to the presence of these radionuclides has been estimated and found 0.89μSv/year and 0.1015μSv/year for 232 Th, 238 U and 40 K, respectively.(Author)

  5. Natural radionuclides in soils from Sao Paulo State cerrado forest

    International Nuclear Information System (INIS)

    Miranda, Marcia V.F.E.S.; Farias, Emerson E.G. de; Cantinha, Rebeca S.; Franca, Elvis J. de

    2015-01-01

    Considering the long life history, forests should be preferentially evaluated for the monitoring of radionuclides, mainly artificial radioisotopes. However, little is known about nuclides from Uranium and Thorium series, as well as, K-40, in soils from the Sao Paulo State forests. Soils are the main reservoir of natural radionuclides for vegetation, thereby deserving attention. Taking into account the advantages of High-Resolution Gamma-ray Spectrometry (HRGS), diverse radionuclides can be quantified simultaneously. In this work natural radionuclides in soils from the Estacao Ecologica de Assis were evaluated by HRGS. Samples of 0-10 cm depth were collected under crown projection of most abundant tree species of long-term plots installed within the Estacao Ecologica de Assis, Sao Paulo State, Brazil. After drying and milling until 0.5 mm particle size, test portions of 30 g were transferred to polypropylene vials, sealed with silicone and kept under controlled conditions until 30 days to achieve secular equilibrium. A group of gamma-ray spectrometers was used to analyze about 27 samples by 80,000 seconds. Activity concentrations of Pb-214, Ac-228 and K-40 and their respective expanded analytical uncertainties at the 95% confidence level were calculated by Genie software from Canberra. Abnormal values were not detected for radionuclides in soils samples, however K-40 activity concentrations changed considerably due to the mineral cycling, in which K and, consequently K-40, is mainly stocked in vegetation in spite of soils. (author)

  6. Artificial Reefs

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — An artificial reef is a human-made underwater structure, typically built to promote marine life in areas with a generally featureless bottom, control erosion, block...

  7. Artificial Metalloenzymes

    NARCIS (Netherlands)

    Rosati, Fiora; Roelfes, Gerard

    Artificial metalloenzymes have emerged as a promising approach to merge the attractive properties of homogeneous catalysis and biocatalysis. The activity and selectivity, including enantioselectivity, of natural metalloenzymes are due to the second coordination sphere interactions provided by the

  8. Radionuclide Sensors for Water Monitoring

    International Nuclear Information System (INIS)

    Grate, Jay W.; Egorov, Oleg B.; DeVol, Timothy A.

    2005-01-01

    Radionuclide contamination in the soil and groundwater at U.S. Department of Energy (DOE) sites is a severe problem that requires monitoring and remediation. Radionuclide measurement techniques are needed to monitor surface waters, groundwater, and process waters. Typically, water samples are collected and transported to an analytical laboratory, where costly radiochemical analyses are performed. To date, there has been very little development of selective radionuclide sensors for alpha- and beta-emitting radionuclides such as 90Sr, 99Tc, and various actinides of interest

  9. History of medical radionuclide production.

    Science.gov (United States)

    Ice, R D

    1995-11-01

    Radionuclide production for medical use originally was incidental to isotope discoveries by physicists and chemists. Once the available radionuclides were identified they were evaluated for potential medical use. Hevesy first used 32P in 1935 to study phosphorous metabolism in rats. Since that time, the development of cyclotrons, linear accelerators, and nuclear reactors have produced hundreds of radionuclides for potential medical use. The history of medical radionuclide production represents an evolutionary, interdisciplinary development of applied nuclear technology. Today the technology is represented by a mature industry and provides medical benefits to millions of patients annually.

  10. Artificial sweeteners

    DEFF Research Database (Denmark)

    Raben, Anne Birgitte; Richelsen, Bjørn

    2012-01-01

    Artificial sweeteners can be a helpful tool to reduce energy intake and body weight and thereby risk for diabetes and cardiovascular diseases (CVD). Considering the prevailing diabesity (obesity and diabetes) epidemic, this can, therefore, be an important alternative to natural, calorie......-containing sweeteners. The purpose of this review is to summarize the current evidence on the effect of artificial sweeteners on body weight, appetite, and risk markers for diabetes and CVD in humans....

  11. Analysis of the behavior of radionuclides migration in fractured medium in different types of rocks matrices; Análise do comportamento da migração de radionuclídeos em meio fraturado em diferentes tipos de matrizes rochosas

    Energy Technology Data Exchange (ETDEWEB)

    Sá, Ludimila Silva Salles de; Silveira, Cláudia Siqueira da; Lima, Zelmo Rodrigues de, E-mail: Ludimilasalles.md@gmail.com, E-mail: siqueira_claudia@yahoo.com.br, E-mail: zelmolima@yahoo.com.br [Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil); Eletrobrás Termonuclear S.A. (ELETRONUCLEAR), Rio de Janeiro, RJ (Brazil); Instituto de Engenharia Nuclear (IEN/CNEN-RJ), Rio de Janeiro, RJ (Brazil)

    2017-11-01

    In management of radioactive wastes, the current trend is to dispose the radioactive waste for long life and high activity in permanent repositories of depth, geologically stable and low permeability. Thus, it is relevant to analyze the groundwater movement process, because the mechanism by which the radionuclides in a repository with fractures could return to the surface would be through the groundwater circulation system. A common problem encountered is the modeling of the migration of radionuclides in a fractured medium. The objective of this work is to evaluate the behavior of the migration of radionuclides in two types of rock matrix, considering the following properties: volumetric density, porosity, distribution coefficient and molecular diffusion coefficient. The physical system adopted consists of the matrix rock containing a discrete fracture in a porous medium saturated with water. The partial differential equations that describe the radionuclide movement were discretized by finite differences, and the Implicit Euler method was adopted. While for the convective term the numerical scheme of progressive differences was used.

  12. EBS Radionuclide Transport Abstraction

    Energy Technology Data Exchange (ETDEWEB)

    J.D. Schreiber

    2005-08-25

    The purpose of this report is to develop and analyze the engineered barrier system (EBS) radionuclide transport abstraction model, consistent with Level I and Level II model validation, as identified in ''Technical Work Plan for: Near-Field Environment and Transport: Engineered Barrier System: Radionuclide Transport Abstraction Model Report Integration'' (BSC 2005 [DIRS 173617]). The EBS radionuclide transport abstraction (or EBS RT Abstraction) is the conceptual model used in the total system performance assessment for the license application (TSPA-LA) to determine the rate of radionuclide releases from the EBS to the unsaturated zone (UZ). The EBS RT Abstraction conceptual model consists of two main components: a flow model and a transport model. Both models are developed mathematically from first principles in order to show explicitly what assumptions, simplifications, and approximations are incorporated into the models used in the TSPA-LA. The flow model defines the pathways for water flow in the EBS and specifies how the flow rate is computed in each pathway. Input to this model includes the seepage flux into a drift. The seepage flux is potentially split by the drip shield, with some (or all) of the flux being diverted by the drip shield and some passing through breaches in the drip shield that might result from corrosion or seismic damage. The flux through drip shield breaches is potentially split by the waste package, with some (or all) of the flux being diverted by the waste package and some passing through waste package breaches that might result from corrosion or seismic damage. Neither the drip shield nor the waste package survives an igneous intrusion, so the flux splitting submodel is not used in the igneous scenario class. The flow model is validated in an independent model validation technical review. The drip shield and waste package flux splitting algorithms are developed and validated using experimental data. The transport

  13. EBS Radionuclide Transport Abstraction

    International Nuclear Information System (INIS)

    J.D. Schreiber

    2005-01-01

    The purpose of this report is to develop and analyze the engineered barrier system (EBS) radionuclide transport abstraction model, consistent with Level I and Level II model validation, as identified in ''Technical Work Plan for: Near-Field Environment and Transport: Engineered Barrier System: Radionuclide Transport Abstraction Model Report Integration'' (BSC 2005 [DIRS 173617]). The EBS radionuclide transport abstraction (or EBS RT Abstraction) is the conceptual model used in the total system performance assessment for the license application (TSPA-LA) to determine the rate of radionuclide releases from the EBS to the unsaturated zone (UZ). The EBS RT Abstraction conceptual model consists of two main components: a flow model and a transport model. Both models are developed mathematically from first principles in order to show explicitly what assumptions, simplifications, and approximations are incorporated into the models used in the TSPA-LA. The flow model defines the pathways for water flow in the EBS and specifies how the flow rate is computed in each pathway. Input to this model includes the seepage flux into a drift. The seepage flux is potentially split by the drip shield, with some (or all) of the flux being diverted by the drip shield and some passing through breaches in the drip shield that might result from corrosion or seismic damage. The flux through drip shield breaches is potentially split by the waste package, with some (or all) of the flux being diverted by the waste package and some passing through waste package breaches that might result from corrosion or seismic damage. Neither the drip shield nor the waste package survives an igneous intrusion, so the flux splitting submodel is not used in the igneous scenario class. The flow model is validated in an independent model validation technical review. The drip shield and waste package flux splitting algorithms are developed and validated using experimental data. The transport model considers

  14. Modifying radionuclide effects

    International Nuclear Information System (INIS)

    Sasser, L.B.

    1983-01-01

    This project involves a study of the relationship of physiological and environmental factors to the metabolism and effects of radionuclides. We have studied placental transfer and suckling as pathways of americium entry into the newborn or juvenile rat. Rats were injected intravenously with 5 μCi of 241 Am while nulliparous (30 days prior to mating), pregnant (day 19 of gestation), or lactating (1 day after parturition), and subsequent litters were killed to determine 241 Am retention. A deficit in reproductive performance was observed in the group injected before mating, as evidenced by reduced number and weight of offspring

  15. Radionuclide therapy in Slovenia

    International Nuclear Information System (INIS)

    Fettich, J.

    2005-01-01

    Full text: In Slovenia 1260 radionuclide therapies are performed per year for a population of 2,000,000 (63/100,000 inhabitants). Approximately half of the patients (691) were treated as outpatients. There are 7 nuclear medicine departments in the country and 4 of them are licensed to perform radionuclide therapy and two have specialised wards for patients receiving radionuclide treatment (10 beds). 131-I is used by far most commonly for benign thyroid diseases and differentiated thyroid Ca treatment. The patients receiving doses of radioactivity below 550 MBqs, i.e. mostly patients with Graves' disease, are treated as outpatients i.e. 610/year, (31/100 000 inhabitants). The patients treated with doses between 740 1110 MBq, mostly hyperthyroid patients with autonomous thyroid tissue (Plummer's disease), 300/year (15/100 000 inhabitants) are hospitalised for 3-5 days in a specialised wards. (Fractionated therapy is not used). 137 therapies were performed for ablation and treatment of metastases in patients with differentiated thyroid cancer receiving 1850 5550 MBq, in 2004 as inpatients. 131-I mIBG is used for treatment of neuroblastoma very occasionally, less than 1/year due to low number of patients. Such patient has to be hospitalised in an adult radiotherapy ward, a situation not preferred by paediatricians. 186-Re HEDP, 153-Sm EDTPM and 89-Sr were used for palliation of bone pain due to bony metastasis usually as outpatients, depending on patient's condition, in only 14 patients in 2004. 186-Re colloid and 90-Y colloid are used for radiosynovectomies in patients with rheumatic and (32/year) and hemophilic (25/year) arthropathies. These patients are not hospitalised. 5 patients were treated with 90-Y anti CD20 MoAB for NHLymphoma, all on outpatient basis and 2 patients received 90-Y Octreotide for metastatic carcinoid also as outpatients. 12 patients received 90-Y colloid intraperitoneally for experimental treatment of carcinosis due to ovarian Ca in 2004

  16. Osteopetrosis: Radiological & Radionuclide Imaging

    International Nuclear Information System (INIS)

    Sit, Cherry; Agrawal, Kanhaiyalal; Fogelman, Ignac; Gnanasegaran, Gopinath

    2015-01-01

    Osteopetrosis is a rare inherited bone disease where bones harden and become abnormally dense. While the diagnosis is clinical, it also greatly relies on appearance of the skeleton radiographically. X-ray, radionuclide bone scintigraphy and magnetic resonance imaging have been reported to identify characteristics of osteopetrosis. We present an interesting case of a 59-year-old man with a history of bilateral hip fractures. He underwent 99m Tc-methylene diphosphonate whole body scan supplemented with single-photon emission computed tomography/computed tomography of spine, which showed increased uptake in the humeri, tibiae and femora, which were in keeping with osteopetrosis

  17. Studies on the Biotribological and Biological Behavior of Thermally Oxidized Ti6Al4V for Use in Artificial Cervical Disk

    Science.gov (United States)

    Wang, Song; Li, Junhui; Lu, Junzhe; Tyagi, Rajnesh; Liao, Zhenhua; Feng, Pingfa; Liu, Weiqiang

    2017-05-01

    The artificial cervical disk was simplified and considered as a ball-on-socket model with the material configuration of ultra-high molecular weight polyethylene and Ti6Al4V (PE-on-TC4). In order to improve the wear resistance, an optimized thermal oxidation (TO) coating was applied on TC4 component. The long-term wear behavior of the model was assessed in vitro using a wear simulator under 10 million cycles (MC) testing intervals. The biological behavior was investigated by bone marrow-derived mesenchymal stem cells (BMSCs) cell attachment and cell viability/proliferation assays, respectively. The total average wear rate for PE/TC4 pair was found to be 0.81 mg/MC, whereas the same was about 0.96 mg/MC for PE/TO pair. The wear rate of the metal has been neglected in comparison with that of the mating polymer. PE component was found to suffer severe damage characterized by scratches, fatigue cracks and arc-shaped wear grooves on the edge zone of ball. The dominant wear mechanism was abrasion for metal component while the dominant failure mechanism was a mix of plowing, fatigue and plastic deformation for polymer component. TO coating improved the cell attachment property of TC4, and the cell viability results were also quite good. TO coating protected TC4 from being plowed and avoided the release of toxic metal ions. However, this intensified the wear of PE component. Considering the biotribological and biological behavior in totality, TO coating could still be promising when applied in articulation surfaces.

  18. Effect of dynamic loading versus static loading on the frictional behavior of a UHMWPE pin in artificial biolubricants

    Directory of Open Access Journals (Sweden)

    Alaleh Safari

    2017-03-01

    Full Text Available To obtain reliable results from in vitro measurements on the tribological behavior of joint implant materials, the parameters of the measurements must simulate in vivo conditions. Although the nature of the load in human joints is dynamic, most of the studies using simple pin-on-disk tribometers were performed with a constant load. The current study focused on investigating the effect of dynamic loading in comparison with static loading in the tribological behavior of ultra-high-molecular-weight polyethylene (UHMWPE sliding against a cobalt chromium molybdenum (CoCrMo counter surface with different lubricants, where the effects of hyaluronic acid (HA and protein content in the lubricants were also investigated. The results suggested that although the dynamic loading did not affect the friction evolution for any of the lubricants, the friction value decreased for the lubricants that did not contain HA. The results showed that higher protein content in the lubricant increased the friction coefficient, however, it provided the highest protection against wear for sliding surfaces.

  19. Radionuclides in nephrology

    International Nuclear Information System (INIS)

    Lausanne, A.B.D.

    1987-01-01

    In 47 expert contributions, this volume provides a summary of the latest research on radionuclides in nephro-urology together with current and new clinical applications especially in renovascular hypertension, kidney transplantation, and metabolic and urological diseases. In addition, attention is given to aspects of basic renal physiology and function and possible applications of nuclear magnetic resonance and spectroscopy in nephro-urology. New testing procedures which promise to improve diagnosis, and new radiopharmaceuticals are described. The reports are divided into eight sections, the first of which features studies on the renin-angiotensin system, cisplatin, atrial natriuretic factor and determining plasma oxalate. Four papers describe a number of new radiopharmaceuticals which have the potential to replace hippuran. In the third section, radionuclide methods for the measurement of renal function parameters are discussed. The book then focuses on the potential role of captopril in the improved diagnosis of renovascular hypertension. Applications of nuclear magnetic resonance and spectroscopy are demonstrated in the diagnosis of acute pyelonephritis, kidney assessment after lithotripsy, kidney evaluation prior to transplantation, and in monitoring renal ischemia during hypotension

  20. The Geochemistry of Technetium: A Summary of the Behavior of an Artificial Element in the Natural Environment

    Energy Technology Data Exchange (ETDEWEB)

    Icenhower, Jonathan P.; Qafoku, Nikolla; Martin, Wayne J.; Zachara, John M.

    2008-12-01

    Interest in the chemistry of technetium has only increased since its discovery in 1937, mainly because of the large and growing inventory of 99Tc generated during fission of 235U, its environmental mobility in oxidizing conditions, and its potential radiotoxicity. For every ton of enriched uranium fuel (3% 235U) that is consumed at a typical burn-up rate, nearly 1 kg of 99Tc is generated. Thus, the mass of 99Tc produced since 1993 has nearly quadrupled, and will likely to continue to increase if more emphasis is placed on nuclear power to slow the accumulation of atmospheric greenhouse gases. In order to gain a comprehensive understanding of the interaction of 99Tc and the natural environment, we review the sources of 99Tc in the nuclear fuel cycle, its chemical properties, radiochemistry, and biogeochemical behavior. We include an evaluation of the use of Re as a chemical analog of Tc, as well as a summary of the redox potential, thermodynamics, sorption, colloidal behavior, and interaction of humic substances with Tc, and the potential for re-oxidation and remobilization of Tc(IV). What emerges is a more complicated picture of Tc behavior than that of an easily tractable transition of Tc(VII) to Tc(IV) with consequent immobilization. Reducing conditions (+200 to +100 mV Eh) are generally thought necessary to cause reduction of Tc(VII) to Tc(IV), but far more important are the presence of reducing agents, such as Fe(II) sorbed onto mineral grains. Catalysis of Tc(VII) by surface-mediated Fe(II) will bring the mobile Tc(VII) species to a lower oxidation state and will form the relatively insoluble Tc(IV)O2∙nH2O, but even as a solid, equilibrium concentrations of aqueous Tc are nearly a factor of 20× above the EPA set drinking water standards. However, sequestration of Tc(IV) into Fe(III)-bearing phases, such as goethite or other hydrous oxyhydroxides of iron, may ameliorate concerns over the mobility of Tc. Further, the outcome of many studies on terrestrial and

  1. Radionuclide - Soil Organic Matter Interactions

    DEFF Research Database (Denmark)

    Carlsen, Lars

    1985-01-01

    Interactions between soil organic matter, i.e. humic and fulvic acids, and radionuclides of primary interest to shallow land burial of low activity solid waste have been reviewed and to some extent studied experimentally. The radionuclides considered in the present study comprise cesium, strontium...

  2. Some parameters of radionuclide kinetics

    International Nuclear Information System (INIS)

    Prokof'ev, O.N.; Smirnov, V.A.; Belen'kij, E.I.

    1978-01-01

    Numerical values of the rates of radionuclide absorption into, and elimination from, bovine organs were determined. Kinetic rate constants of radionuclides such as 89 Sr, 99 Mo, 131 I, 132 Tl, and 140 Be were calculated. The calculations were done for muscle, liver, and kidney

  3. Field test of radionuclide migration in loess aerated zone

    International Nuclear Information System (INIS)

    Guo Zede; Wang Zhiming; Li Shushen; Jiang Gang; Huang Qingchun; Yang Duanjie; Tadao Tanaka; Masayuki Mukai; Hedio Kamiyama

    2000-01-01

    A two year field study of radionuclide migration in loess aerated zone was carried out at CIRP's Field Test Site, with total 6 test groups under both natural rainfall and artificial sprinkling conditions, and 3 H, 60 Co, 85 Sr and 134 Cs were used as tracers. The concentration distributions in the soil were measured by periodic sampling soil and direct measurement. Meanwhile, systematic water movement observation was performed as support. The author firstly gives a brief introduction about the test arrangement, then presents the migration results of 3 H. The results are compared with the data obtained from other work both in laboratory and in the field. Very good agreement is achieved, which demonstrates the reliability of the developed method. The results show that the loess has very strong adsorption capacity to Co and Cs, and relatively strong adsorption capacity to Sr. For two years, concentration peaks of 60 Co and 134 Cs had no significant movement (less than 1 cm), under natural and artificial sprinkling conditions. Under the artificial sprinkling condition, peak of 85 Sr moved about 13 cm in two years, while less than 2 cm under the natural rainfall condition. Though the loess medium has very strong adsorption to 60 Co and 134 Cs, a small fraction of each radionuclides moved much faster than the peaks under artificial sprinkling condition. It was also observed that 85 Sr had two peaks in its concentration distribution curves. These phenomena are very important to safety assessment of radioactive waste disposal

  4. Erosion of atmospherically deposited radionuclides as affected by soil disaggregation mechanisms

    International Nuclear Information System (INIS)

    Claval, D.; Garcia-Sanchez, L.; Real, J.; Rouxel, R.; Mauger, S.; Sellier, L.

    2004-01-01

    The interactions of soil disaggregation with radionuclide erosion were studied under controlled conditions in the laboratory on samples from a loamy silty-sandy soil. The fate of 134 Cs and 85 Sr was monitored on soil aggregates and on small plots, with time resolution ranging from minutes to hours after contamination. Analytical experiments reproducing disaggregation mechanisms on aggregates showed that disaggregation controls both erosion and sorption. Compared to differential swelling, air explosion mobilized the most by producing finer particles and increasing five-fold sorption. For all the mechanisms studied, a significant part of the contamination was still unsorbed on the aggregates after an hour. Global experiments on contaminated sloping plots submitted to artificial rainfalls showed radionuclide erosion fluctuations and their origin. Wet radionuclide deposition increased short-term erosion by 50% compared to dry deposition. A developed soil crust when contaminated decreased radionuclide erosion by a factor 2 compared to other initial soil states. These erosion fluctuations were more significant for 134 Cs than 85 Sr, known to have better affinity to soil matrix. These findings confirm the role of disaggregation on radionuclide erosion. Our data support a conceptual model of radionuclide erosion at the small plot scale in two steps: (1) radionuclide non-equilibrium sorption on mobile particles, resulting from simultaneous sorption and disaggregation during wet deposition and (2) later radionuclide transport by runoff with suspended matter

  5. Beta-emitting radionuclides for peptide receptor radionuclide therapy.

    Science.gov (United States)

    Parus, J L; Mikolajczak, R

    2012-01-01

    The paper focuses on the β-emitting radionuclides which might be useful for peptide receptor radionuclide therapy, PRRT. For the effective design of the radiopharmaceutical, the choice of radionuclide will depend on the purpose for which the radioligand is being used and on the physicochemical properties of the radionuclide. The important factor is also the availability and the cost of production. The physical characteristics of several radionuclides which are currently used or can be considered as potential candidates for PRRT is provided, followed by short description of production methods and chemical aspects of their use in preparation of peptide-based radiopharmaceuticals. Somatostatin analogues labeled with radionuclides have been a successful example of PRRT. For treatment of patients with inoperable or metastasized neuroendocrine tumors, somatostatin analogues labeled with the radioisotopes (111)In, (90)Y and (177)Lu have been used so far. Labeling with (111)In, mainly an Auger electron emitter, resulted in no reduction of tumor size while somatostatin analogues labeled with (90)Y and (177)Lu gave overall positive response and improved the patients' quality of life. These promising results together with the increasing availability of other β-emitting radionuclides are a good basis for further studies.

  6. Radioactivity of natural and artificial building materials - a comparative study.

    Science.gov (United States)

    Szabó, Zs; Völgyesi, P; Nagy, H É; Szabó, Cs; Kis, Z; Csorba, O

    2013-04-01

    Building materials and their additives contain radioactive isotopes, which can increase both external and internal radioactive exposures of humans. In this study Hungarian natural (adobe) and artificial (brick, concrete, coal slag, coal slag concrete and gas silicate) building materials were examined. We qualified 40 samples based on their radium equivalent, activity concentration, external hazard and internal hazard indices and the determined threshold values of these parameters. Absorbed dose rate and annual effective dose for inhabitants living in buildings made of these building materials were also evaluated. The calculations are based on (226)Ra, (232)Th and (40)K activity concentrations determined by gamma-ray spectrometry. Measured radionuclide concentrations and hence, calculated indices and doses of artificial building materials show a rather disparate distribution compared to adobes. The studied coal slag samples among the artificial building materials have elevated (226)Ra content. Natural, i.e. adobe and also brick samples contain higher amount of (40)K compared to other artificial building materials. Correlation coefficients among radionuclide concentrations are consistent with the values in the literature and connected to the natural geochemical behavior of U, Th and K elements. Seven samples (coal slag and coal slag concrete) exceed any of the threshold values of the calculated hazard indices, however only three of them are considered to be risky to use according to the fact that the building material was used in bulk amount or in restricted usage. It is shown, that using different indices can lead to different conclusions; hence we recommend considering more of the indices at the same time when building materials are studied. Additionally, adding two times their statistical uncertainties to their values before comparing to thresholds should be considered for providing a more conservative qualification. We have defined radon hazard portion to point

  7. Artificial intelligence

    International Nuclear Information System (INIS)

    Perret-Galix, D.

    1992-01-01

    A vivid example of the growing need for frontier physics experiments to make use of frontier technology is in the field of artificial intelligence and related themes. This was reflected in the second international workshop on 'Software Engineering, Artificial Intelligence and Expert Systems in High Energy and Nuclear Physics' which took place from 13-18 January at France Telecom's Agelonde site at La Londe des Maures, Provence. It was the second in a series, the first having been held at Lyon in 1990

  8. Artificial Intelligence

    CERN Document Server

    Warwick, Kevin

    2011-01-01

    if AI is outside your field, or you know something of the subject and would like to know more then Artificial Intelligence: The Basics is a brilliant primer.' - Nick Smith, Engineering and Technology Magazine November 2011 Artificial Intelligence: The Basics is a concise and cutting-edge introduction to the fast moving world of AI. The author Kevin Warwick, a pioneer in the field, examines issues of what it means to be man or machine and looks at advances in robotics which have blurred the boundaries. Topics covered include: how intelligence can be defined whether machines can 'think' sensory

  9. A robust behavior of Feed Forward Back propagation algorithm of Artificial Neural Networks in the application of vertical electrical sounding data inversion

    Directory of Open Access Journals (Sweden)

    Y. Srinivas

    2012-09-01

    Full Text Available The applications of intelligent techniques have increased exponentially in recent days to study most of the non-linear parameters. In particular, the behavior of earth resembles the non-linearity applications. An efficient tool is needed for the interpretation of geophysical parameters to study the subsurface of the earth. Artificial Neural Networks (ANN perform certain tasks if the structure of the network is modified accordingly for the purpose it has been used. The three most robust networks were taken and comparatively analyzed for their performance to choose the appropriate network. The single-layer feed-forward neural network with the back propagation algorithm is chosen as one of the well-suited networks after comparing the results. Initially, certain synthetic data sets of all three-layer curves have been taken for training the network, and the network is validated by the field datasets collected from Tuticorin Coastal Region (78°7′30"E and 8°48′45"N, Tamil Nadu, India. The interpretation has been done successfully using the corresponding learning algorithm in the present study. With proper training of back propagation networks, it tends to give the resistivity and thickness of the subsurface layer model of the field resistivity data concerning the synthetic data trained earlier in the appropriate network. The network is trained with more Vertical Electrical Sounding (VES data, and this trained network is demonstrated by the field data. Groundwater table depth also has been modeled.

  10. Targeted radionuclide therapies for pancreatic cancer.

    Science.gov (United States)

    Shah, M; Da Silva, R; Gravekamp, C; Libutti, S K; Abraham, T; Dadachova, E

    2015-08-01

    Pancreatic malignancies, the fourth leading cause of cancer deaths, have an aggressive behavior with poor prognosis, resulting in a 5-year survival rate of only 4%. It is typically a silent malignancy until patients develop metastatic disease. Targeted radionuclide therapies of cancer such as radiolabeled peptides, which bind to the receptors overexpressed by cancer cells and radiolabeled antibodies to tumor-specific antigens provide a viable alternative to chemotherapy and external beam radiation of metastatic cancers. Multiple clinical trials of targeted radionuclide therapy of pancreatic cancer have been performed in the last decade and demonstrated safety and potential efficacy of radionuclide therapy for treatment of this formidable disease. Although a lot of progress has been made in treatment of pancreatic neuroendocrine tumors with radiolabeled (90)Y and (177)Lu somatostatin peptide analogs, pancreatic adenocarcinomas remain a major challenge. Novel approaches such as peptides and antibodies radiolabeled with alpha emitters, pre-targeting, bispecific antibodies and biological therapy based on the radioactive tumorlytic bacteria might offer a potential breakthrough in treatment of pancreatic adenocarcinomas.

  11. The accumulation of radionuclides in stevia (Stevia rebaudiana Bertoni) in conditions of the Ararat valley

    International Nuclear Information System (INIS)

    Babakhanyan, M.A.; Ghalachyan, L.M.; Hovhannisyan, L.E.

    2013-01-01

    Accumulation peculiarities of artificial ( 137 Cs, 90 Sr) and natural (U) radionuclides (RN) in Stevia (Stevia rebaundiana Bertoni), grown in hydroponics and soils near G.S. Davtyan Institute of Hydroponics Problems have been studied. It turned out that the raw material of Stevia, cultivated in open-air hydroponics was clearer than the soil variant. The content of controlled artificial RN ( 137 Cs, 90 Sr) in Stevia cultivated in soil and in hydroponics conditions hasn't exceeded the MAC

  12. Gut-related radionuclide studies

    International Nuclear Information System (INIS)

    Sullivan, M.F.

    1982-01-01

    This project is concerned with the behavior of radioactive materials that may be ingested as a consequence of a reactor accident, unavoidable occupational exposure, or after release to the environment and incorporation into the food chain. Current emphasis is directed toward evaluating hazards from ingested actinides as a function of animal age, species, nutrition, and diet, or chemicophysical state of the actinide. Recent observations indicate that the influence of chemical form on plutonium absorption observed at high mass levels does not occur at low mass concentrations. For example, at doses of 0.6 μg/kg there was no difference between absorption of the carbonate, citrate or nitrate forms of plutonium. However, at 1.5 mg/kg, the citrate was absorbed in quantities 30 times higher than the nitrate. The opposite effect occurred for neptunium GI absorption. Furthermore, it was demonstrated that materials such as citrus fruit juices and calcium, as well as drugs that affect GI function (such as aspirin and DTPA), markedly influence GI absorption of plutonium. Such studies provide evidence that diet and nutritional state should be considered in establishing safe limits for radionuclides that may be ingested

  13. Radionuclides in an underground environment

    International Nuclear Information System (INIS)

    Thompson, J.L.

    1996-01-01

    In the 100 years since Becquerel recognized radioactivity, mankind has been very successful in producing large amounts of radioactive materials. We have been less successful in reaching a consensus on how to dispose of the billions of curies of fission products and transuranics resulting from nuclear weapons testing, electrical power generation, medical research, and a variety of other human endeavors. Many countries, including the United States, favor underground burial as a means of disposing of radioactive wastes. There are, however, serious questions about how such buried wastes may behave in the underground environment and particularly how they might eventually contaminate water, air and soil resources on which we are dependent. This paper describes research done in the United States in the state of Nevada on the behavior of radioactive materials placed underground. During the last thirty years, a series of ''experiments'' conducted for other purposes (testing of nuclear weapons) have resulted in a wide variety of fission products and actinides being injected in rock strata both above and below the water table. Variables which seem to control the movement of these radionuclides include the physical form (occlusion versus surface deposition), the chemical oxidation state, sorption by mineral phases of the host rock, and the hydrologic properties of the medium. The information gained from these studies should be relevant to planning for remediation of nuclear facilities elsewhere in the world and for long-term storage of nuclear wastes

  14. Radionuclide transverse section imager

    International Nuclear Information System (INIS)

    Stoddart, H.F.

    1980-01-01

    A radioisotope scanning apparatus for use in nuclear medicine is described in detail. The apparatus enables the quantification and spatial location of the radioactivity in a body section of a patient to be determined with high sensitivity. It consists of an array of highly focussed collimators arranged such that adjacent collimators move in the same circumferential but opposite radial directions. The explicit movements of the gantry are described in detail and may be controlled by a general purpose computer. The use of highly focussed collimators allows both a reasonable solid angle of acceptance and also high target to background images; additionally, dual radionuclide pharmaceutical studies can be performed simultaneously. It is claimed that the high sensitivity of the system permits the early diagnosis of pathological changes and the images obtained show accurately the location and shape of physiological abnormalities. (UK)

  15. Radionuclide reporter gene imaging

    International Nuclear Information System (INIS)

    Min, Jung Joon

    2004-01-01

    Recent progress in the development of non-invasive imaging technologies continues to strengthen the role of molecular imaging biological research. These tools have been validated recently in variety of research models, and have been shown to provide continuous quantitative monitoring of the location(s), magnitude, and time-variation of gene expression. This article reviews the principles, characteristics, categories and the use of radionuclide reporter gene imaging technologies as they have been used in imaging cell trafficking, imaging gene therapy, imaging endogenous gene expression and imaging molecular interactions. The studies published to date demonstrate that reporter gene imaging technologies will help to accelerate model validation as well as allow for clinical monitoring of human diseases

  16. Radioactivity, radionuclides, radiation

    CERN Document Server

    Magill, Joseph

    2005-01-01

    RADIOACTIVITY – RADIONUCLIDES – RADIATION is suitable for a general audience interested in topical environmental and human health radiological issues such as radiation exposure in aircraft, food sterilisation, nuclear medicine, radon gas, radiation dispersion devices ("dirty bombs")… It leads the interested reader through the three Rs of nuclear science, to the forefront of research and developments in the field. The book is also suitable for students and professionals in the related disciplines of nuclear and radiochemistry, health physics, environmental sciences, nuclear and astrophysics. Recent developments in the areas of exotic decay modes (bound beta decay of ‘bare’ or fully ionized nuclei), laser transmutation, nuclear forensics, radiation hormesis and the LNT hypothesis are covered. Atomic mass data for over 3000 nuclides from the most recent (2003) evaluation are included.

  17. Radionuclide Incorporation and Long Term Performance of Apatite Waste Forms

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Jianwei [Louisiana State Univ., Baton Rouge, LA (United States); Lian, Jie [Rensselaer Polytechnic Inst., Troy, NY (United States); Gao, Fei [Univ. of Michigan, Ann Arbor, MI (United States)

    2016-01-04

    This project aims to combines state-of-the-art experimental and characterization techniques with atomistic simulations based on density functional theory (DFT) and molecular dynamics (MD) simulations. With an initial focus on long-lived I-129 and other radionuclides such as Cs, Sr in apatite structure, specific research objectives include the atomic scale understanding of: (1) incorporation behavior of the radionuclides and their effects on the crystal chemistry and phase stability; (2) stability and microstructure evolution of designed waste forms under coupled temperature and radiation environments; (3) incorporation and migration energetics of radionuclides and release behaviors as probed by DFT and molecular dynamics (MD) simulations; and (4) chemical durability as measured in dissolution experiments for long term performance evaluation and model validation.

  18. Vertical soil migration of radionuclide fallout from the Chernobyl' accident

    International Nuclear Information System (INIS)

    Silant'ev, A.N.; Shkuratova, I.G.; Bobovnikova, T.I.

    1989-01-01

    The most suitable model for describing the behavior of radionuclide fallout on a soil surface is quasidiffusion transfer with directional transfer taken into account. The parameter values for this have been determined previously and are supplemented by the results of this work. To investigate the initial radionuclide distribution along the soil profile, monolithic soil samples 5 cm thick were taken in June-September 1986 in areas which had been subjected to contamination due to the Chernobyl' accident. The samples taken were cut up into layers. The first layer, 0.5 cm thick, was cut off from the surface of the soil monolith together with the grass. The next layer cut off was also 0.5 cm thick. Then two layers, each 1 cm in thickness, were cut off. The thickness of the last layer was 2 cm. The vertical distribution of radionuclides along the soil profile which was examined may be called the initial distribution, which will then change due to nonimmediate migration of radionuclides in the soil. Based on the research which has been performed, the following conclusions may be drawn. One portion of the radionuclides resulting from fallout is trapped by plant cover, while the other enters immediately into the soil. For a thick plant covering, about 80% of the radionuclide fallout is sorbed by the grass; for sparse cover, about 40%. The radionuclides entering the soil along with rainwater penetrate into the soil depths, producing contamination which falls off exponentially with depth. The exponent index is close to 1 cm -1 . In a forest, the main amount of radionuclide fallout is trapped by litter. Approximately 10% of the contamination fallout penetrates beneath the litter

  19. A study on the characteristics of colloid-associated radionuclide transport in porous media

    International Nuclear Information System (INIS)

    Jeong, Yun Chang

    1997-02-01

    Recently, the radionuclide transport in the form of colloids has been focused intensively in the safety assessment of a radioactive waste repository. As colloids are considered to be able to increase the transport rate of radionuclide through geologic media, the transport of radionuclide should be adjusted by the presence of colloids. The migration of dissolved radionuclide is expected to depend on various process such as advection, dispersion and interactions with soils, and, in addition, the transport of colloid-mediated radionuclide is considered to be more complicated because of the interactions between radionuclides and colloids. In this paper the migration behavior of colloid-associated radionuclides within subsurface are reviewed and studied in detail. The colloid-mediated transport system was modelled and simulated in order to illustrate the effects of colloids on the transport of radionuclide in the aquifer system. The transport rate of radionuclide is mainly controlled by a retardation factor which is controlled by colloidal behaviors, degree of adsorption, and the related geologic parameters. Therefore it is necessary to carefully understand the accelerating tendency of the retardation difference factor, and in this study the trends are analyzed, described and the retardation difference factor is mathematically defined, simplified and applied practically to the safety and performance assessment of a future repository

  20. Artificial Intelligence.

    Science.gov (United States)

    Wash, Darrel Patrick

    1989-01-01

    Making a machine seem intelligent is not easy. As a consequence, demand has been rising for computer professionals skilled in artificial intelligence and is likely to continue to go up. These workers develop expert systems and solve the mysteries of machine vision, natural language processing, and neural networks. (Editor)

  1. Gut-related studies of radionuclide toxicity

    International Nuclear Information System (INIS)

    Anon.

    1981-01-01

    This project is concerned with the behavior of radioactive materials of importance in the nuclear industry that may be ingested as a consequence of a reactor accident, of unavoidable occupational exposure, or after release to the environment and incorporation into the food chain. Current emphasis is directed toward evaluating hazards from ingested actinides as a function of animal age, animal species, animal nutritional state, diet or chemicophysical state of the radionuclide. It is also concerned with nuclides that may be inhaled and passed through the gastrointestinal tract after clearance from the lungs

  2. Short lived radionuclides in therapy

    International Nuclear Information System (INIS)

    Spencer, R.P.

    1987-01-01

    A brief article examines some of the arguments for using shorter lived radionuclides in therapy. Shorter lived radionuclides would 1) reduce over-saturation of the target lesions and consequently reduce irradiation of other parts of the body, 2) reduce the DNA repair capacity of the target cells, 3) reduce the 'escape' of the radionuclide from the major therapeutic locale, 4) reduce the portion of the patient's life span during which the patient is receiving radiotherapy and 5) be useful in evaluating the radiation effects of fractionated radiotherapy. (U.K.)

  3. Acute Mental Discomfort Associated with Suicide Behavior in a Clinical Sample of Patients with Affective Disorders: Ascertaining Critical Variables Using Artificial Intelligence Tools.

    Science.gov (United States)

    Morales, Susana; Barros, Jorge; Echávarri, Orietta; García, Fabián; Osses, Alex; Moya, Claudia; Maino, María Paz; Fischman, Ronit; Núñez, Catalina; Szmulewicz, Tita; Tomicic, Alemka

    2017-01-01

    In efforts to develop reliable methods to detect the likelihood of impending suicidal behaviors, we have proposed the following. To gain a deeper understanding of the state of suicide risk by determining the combination of variables that distinguishes between groups with and without suicide risk. A study involving 707 patients consulting for mental health issues in three health centers in Greater Santiago, Chile. Using 345 variables, an analysis was carried out with artificial intelligence tools, Cross Industry Standard Process for Data Mining processes, and decision tree techniques. The basic algorithm was top-down, and the most suitable division produced by the tree was selected by using the lowest Gini index as a criterion and by looping it until the condition of belonging to the group with suicidal behavior was fulfilled. Four trees distinguishing the groups were obtained, of which the elements of one were analyzed in greater detail, since this tree included both clinical and personality variables. This specific tree consists of six nodes without suicide risk and eight nodes with suicide risk (tree decision 01, accuracy 0.674, precision 0.652, recall 0.678, specificity 0.670, F measure 0.665, receiver operating characteristic (ROC) area under the curve (AUC) 73.35%; tree decision 02, accuracy 0.669, precision 0.642, recall 0.694, specificity 0.647, F measure 0.667, ROC AUC 68.91%; tree decision 03, accuracy 0.681, precision 0.675, recall 0.638, specificity 0.721, F measure, 0.656, ROC AUC 65.86%; tree decision 04, accuracy 0.714, precision 0.734, recall 0.628, specificity 0.792, F measure 0.677, ROC AUC 58.85%). This study defines the interactions among a group of variables associated with suicidal ideation and behavior. By using these variables, it may be possible to create a quick and easy-to-use tool. As such, psychotherapeutic interventions could be designed to mitigate the impact of these variables on the emotional state of individuals, thereby reducing

  4. Uptake of radionuclides by farm animals close to a major nuclear installation

    International Nuclear Information System (INIS)

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

    1984-01-01

    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. The routine discharges from the plant have resulted in enhanced levels of several artificial radionuclides in the local environment. The annual depositions of 90 Sr and 137 Cs at the farm were a factor of about five higher than the average deposition of these radionuclides in the UK. Even if extremely cautious assumptions concerning local eating habits are made, the consumption of meat and dairy products from this farm would give rise to an annual activity intake of less than one percent of the limit for adult members of the public. (orig./HP)

  5. Report on the intercomparison run IAEA-306 radionuclides in Baltic Sea sediment

    International Nuclear Information System (INIS)

    Ballestra, S.; Vas, D.; Lopez, J.J.; Noshkin, V.

    1989-10-01

    The results of an intercomparison exercise on a Baltic Sea sediment sample, coded as IAEA-306, designed for the determination of artificial and natural radionuclide levels, are reported. This sample was collected in the fall 1986. It was anticipated that the concentrations of the artificial radionuclides in this sediment would be higher than the environmental levels usually found and, therefore, would constitute an excellent intercomparison sample. The data from 84 laboratories representing 34 countries have been evaluated. The most frequently measured radionuclides are: 90 Sr, 125 Sb, 134 Cs, 137 Cs, 238 Pu, 239+240 Pu, 241 Am, 40 K, 210 Pb- 210 Po, 226 Ra, 228 Ra, 228 Th, 230 Th, 232 Th, 234 U and 238 U. 6 refs, 13 tabs

  6. An experimental study on the application of radionuclide imaging in repair of the bone defect

    Directory of Open Access Journals (Sweden)

    Weimin Zhu

    2011-08-01

    Full Text Available The aim of our study was to validate the effect of radionuclide imaging in early monitoring of the bone’s reconstruction, the animal model of bone defect was made on the rabbits repaired with HA artificial bone. The ability of bone defect repair was evaluated by using radionuclide bone imaging at 2, 4, 8 and 12 weeks postoperatively. The results indicate that the experimental group stimulated more bone formation than that of the control group. The differences of the bone reconstruction ability were statistically significant (p<0.05. The nano-HA artificial has good bone conduction, and it can be used for the treatment of bone defects. Radionuclide imaging may be an effective and first choice method for the early monitoring of the bone’s reconstruction.

  7. National Low-Level Waste Management Program Radionuclide Report Series

    International Nuclear Information System (INIS)

    Rudin, M.J.; Garcia, R.S.

    1992-02-01

    This report, Volume 4 of the National Low-Level Radioactive Waste Management Program Radionuclide Report Series, discusses radiological and chemical characteristics about iodine-129. This report also includes discussions about waste streams that contain iodine-129, waste forms that contain iodine-129, and iodine-129's behavior in the environment, as well as in the human body

  8. National Low-Level Waste Management Program Radionuclide Report Series

    International Nuclear Information System (INIS)

    Rudin, M.J.; Garcia, R.S.

    1992-02-01

    This report, Volume 3 of the National Low-Level Radioactive Waste Management Program Radionuclide Report Series, discusses the radiological and chemical characteristics of carbon-14. The report also discusses waste streams that contain carbon-14, waste forms that contain carbon-14, and carbon-14 behavior in the environment and in the human body

  9. National Low-Level Waste Management Program Radionuclide Report Series

    International Nuclear Information System (INIS)

    Rudin, M.J.; Stanton, C.; Patterson, R.G.; Garcia, R.S.

    1992-02-01

    This report, Volume 2 of the National Low-Level Radioactive Waste Management Program Radionuclide Report Series, discusses radiological and chemical characteristics of technetium-99. This report also includes discussions about waste streams in which technetium-99 can be found, waste forms that contain technetium-99, and technetium-99's behavior in the environment and in the human body

  10. Natural and Artificial Radioactivity in Drinking Water in Malaga, Spain

    International Nuclear Information System (INIS)

    Duenas, C.; Fernandez, M.C.; Gordo, E.; Canete, S.; Perez, M.

    2011-01-01

    Water has a vast importance for numerous human activities, so that securing supplies of drinking water of a standard quality is becoming more and more difficult. The measurement of radioactivity in drinking water permits us to determine the exposure of the population to radiation from the habitual consumption of water. The occurrence of radionuclides in drinking water gives rise to internal exposure of humans, directly on the decay of radionuclides taken into the body through ingestion and inhalation and indirectly when they are incorporated as part of the food-chain The measurement of radioactivity in drinking water permits us to determine the exposure of population to radiation from the habitual consumption of water. An intensive study of the water supply in the city of Malaga during 2002-2010 has been carried out in order to determine the gross alpha activities, gross beta activities and natural and artificial radionuclides present in drinking water. A data base on natural and artificial radioactivity in water was produced. The results indicated that a high percentage of the water sample contains a total gross alpha and beta less than 0.10 Bq/l and 1 Bq/l respectively. The main objectives were: 1) to analyses gross alpha and gross beta activities and to know the statistical distributions. 2) to study the levels of natural and artificial radionuclides 3) to determine a possible mathematical correlation between the radionuclides and several factors.

  11. Natural and artificial radioactivity in coastal regions of UK

    International Nuclear Information System (INIS)

    McDonald, P.; Cook, G.T.; Baxter, M.S.

    1991-01-01

    The transport and bioaccumulation of natural and artificial radionuclides in the coastal regions of UK have been investigated. The magnitude of radionuclide concentration variation throughout the UK coastline has been quantified and where appropriate source terms have been identified. Sites bordering the Irish Sea show the highest levels of artificial radioactivity which are derived from past Sellafield discharges. Enhanced concentrations of natural radioactivity were found in all Whitehaven samples, in sediment at Blackhall Colliery near Hartlepool and in mussels at Aberdeen. Highest radionuclide concentrations were present in Whitehaven mussels - 3124Bqkg -1 dry weight of 210 Po. Excluding sites bordering the Irish Sea, levels of natural radionuclides ( 210 Pb, 210 Po, 232 Th, 238 U) were greatly in excess of the artificial radionuclide concentrations in all sample types. The biological preference for accumulation of 210 Po relative to its grandparent 210 Pb is evident. 210 Po/ 210 Pb activity ratios range between 2 and 40 in mussels, winkles and seaweed but only between 0.24 and 1.3 in sediments and sea water. Radiologically, the highest radiation exposure to the public evident from the results would be from the ingestion of Whitehaven mussels (3.2mSv y -1 ), the greatest single contribution being from technologically enhanced 210 Po. (Author)

  12. Radionuclide Retention in Concrete Wasteforms

    Energy Technology Data Exchange (ETDEWEB)

    Bovaird, Chase C.; Jansik, Danielle P.; Wellman, Dawn M.; Wood, Marcus I.

    2011-09-30

    Assessing long-term performance of Category 3 waste cement grouts for radionuclide encasement requires knowledge of the radionuclide-cement interactions and mechanisms of retention (i.e., sorption or precipitation); the mechanism of contaminant release; the significance of contaminant release pathways; how wasteform performance is affected by the full range of environmental conditions within the disposal facility; the process of wasteform aging under conditions that are representative of processes occurring in response to changing environmental conditions within the disposal facility; the effect of wasteform aging on chemical, physical, and radiological properties; and the associated impact on contaminant release. This knowledge will enable accurate prediction of radionuclide fate when the wasteforms come in contact with groundwater. The information present in the report provides data that (1) measures the effect of concrete wasteform properties likely to influence radionuclide migration; and (2) quantifies the rate of carbonation of concrete materials in a simulated vadose zone repository.

  13. Radionuclides in the food chain

    International Nuclear Information System (INIS)

    Harley, J.H.; Schmidt, G.D.

    1988-01-01

    Radionuclides in the Food Chain reviews past experience in meeting the challenge of radionuclide contamination of foodstuffs and water sources and, in the wake of the reactor accidents at Chernobyl and Three Mile Island, presents current concepts and programs relating to measurement, surveillance, effects, risk management, evaluation guidelines, and control and regulatory activities. This volume, based on a symposium sponsored by the International Life Sciences Institute in association with the International Institute for Applied Systems Analysis, which brought together both radiation experts and food industry policymakers, examines such vital topics as structural problems in large-scale crisis-managment systems; dose assessment from man-made sources; international recommendations on radiation protection; airborne contamination, as well as aquatic and soilborne radionuclides; food-chain contamination from testing nuclear devices; long-term health effects of radionuclides in food and water supplies; and use of mathematical models in risk assessment and management. (orig.)

  14. Radionuclide methods in pediatric cardiology

    International Nuclear Information System (INIS)

    Reich, O.; Ruth, C.; Samanek, M.

    1990-01-01

    The use of radionuclide methods in pediatric cardiology is discussed for non-invasive evaluation of myocardial function and perfusion, regional lung perfusion and ventilation, and for measuring central and peripheral hemodynamics. (H.W.). 16 refs

  15. Artificial Intelligence.

    Science.gov (United States)

    Lawrence, David R; Palacios-González, César; Harris, John

    2016-04-01

    It seems natural to think that the same prudential and ethical reasons for mutual respect and tolerance that one has vis-à-vis other human persons would hold toward newly encountered paradigmatic but nonhuman biological persons. One also tends to think that they would have similar reasons for treating we humans as creatures that count morally in our own right. This line of thought transcends biological boundaries-namely, with regard to artificially (super)intelligent persons-but is this a safe assumption? The issue concerns ultimate moral significance: the significance possessed by human persons, persons from other planets, and hypothetical nonorganic persons in the form of artificial intelligence (AI). This article investigates why our possible relations to AI persons could be more complicated than they first might appear, given that they might possess a radically different nature to us, to the point that civilized or peaceful coexistence in a determinate geographical space could be impossible to achieve.

  16. Artificial intelligence

    OpenAIRE

    Duda, Antonín

    2009-01-01

    Abstract : Issue of this work is to acquaint the reader with the history of artificial inteligence, esspecialy branch of chess computing. Main attention is given to progress from fifties to the present. The work also deals with fighting chess programs against each other, and against human opponents. The greatest attention is focused on 1997 and duel Garry Kasparov against chess program Deep Blue. The work is divided into chapters according to chronological order.

  17. Artificial Wormhole

    OpenAIRE

    Kirillov, A. A.; Savelova, E. P.

    2012-01-01

    It is shown that recently reported result by the OPERA Collaboration (arXive:1109.4897) of an early arrival time of muon neutrinos with respect to the speed of light in vacuum does not violate standard physical laws. We show that vacuum polarization effects in intensive external fields may form a wormhole-like object. The simplest theory of such an effect is presented and basic principles of formation of an artificial wormhole are also considered.

  18. Artificial vision.

    Science.gov (United States)

    Zarbin, M; Montemagno, C; Leary, J; Ritch, R

    2011-09-01

    A number treatment options are emerging for patients with retinal degenerative disease, including gene therapy, trophic factor therapy, visual cycle inhibitors (e.g., for patients with Stargardt disease and allied conditions), and cell transplantation. A radically different approach, which will augment but not replace these options, is termed neural prosthetics ("artificial vision"). Although rewiring of inner retinal circuits and inner retinal neuronal degeneration occur in association with photoreceptor degeneration in retinitis pigmentosa (RP), it is possible to create visually useful percepts by stimulating retinal ganglion cells electrically. This fact has lead to the development of techniques to induce photosensitivity in cells that are not light sensitive normally as well as to the development of the bionic retina. Advances in artificial vision continue at a robust pace. These advances are based on the use of molecular engineering and nanotechnology to render cells light-sensitive, to target ion channels to the appropriate cell type (e.g., bipolar cell) and/or cell region (e.g., dendritic tree vs. soma), and on sophisticated image processing algorithms that take advantage of our knowledge of signal processing in the retina. Combined with advances in gene therapy, pathway-based therapy, and cell-based therapy, "artificial vision" technologies create a powerful armamentarium with which ophthalmologists will be able to treat blindness in patients who have a variety of degenerative retinal diseases.

  19. Natural radionuclides in an eucalyptus forest located in the south of Spain

    International Nuclear Information System (INIS)

    Vaca, F.; Manjon, G.; Garcia-Leon, M.

    2001-01-01

    Eucalyptus forests can be considered as the main source of raw material for the pulp industry of Spain. This environment was selected for a radioactivity study because natural and artificial radionuclides can be transferred into the pulp mills, associated with raw material, wood and barks, where they are concentrated by industrial processes, becoming a cause of doses. Radionuclide concentration of natural radionuclides ( 238 U, 234 U, 228 Th, 230 Th, 232 Th) were determined by alpha- and gamma-spectrometry. Well-established radiochemical procedures were applied to environmental samples in order to isolate these radionuclides. A comparison between 228 Th activity, determined by gamma-spectrometry, and 232 Th activity, determined by alpha-spectrometry, was used as quality control parameter for analyses. The concentration factors were finally evaluated from experimental data.

  20. Radionuclide brain scanning

    International Nuclear Information System (INIS)

    Abdel-Dayem, H.

    1992-01-01

    At one stage of medical imaging development, radionuclide brain scanning was the only technique available for imaging of the brain. Advent of CT and MRI pushed it to the background. It regained some of the grounds lost to ''allied advances'' with the introduction of brain perfusion radiopharmaceuticals. Positron emission tomography is a promising functional imaging modality that at present will remain as a research tool in special centres in developed countries. However, clinically useful developments will gradually percolate from PET to SPECT. The non-nuclear imaging methods are totally instrument dependent; they are somewhat like escalators, which can go that far and no further. Nuclear imaging has an unlimited scope for advance because of the new developments in radiopharmaceuticals. As the introduction of a radiopharmaceutical is less costly than buying new instruments, the recent advances in nuclear imaging are gradually perfusing through the developing countries also. Therefore, it is essential to follow very closely PET developments because what is research today might become routine tomorrow

  1. Radionuclide salivary gland imaging

    Energy Technology Data Exchange (ETDEWEB)

    Mishkin, F.S.

    1981-10-01

    Salivary gland imaging with 99mTc as pertechnetate provides functional information concerning trapping and excretion of the parotid and submandibular glands. Anatomic information gained often adds little to clinical evaluation. On the other hand, functional information may detect subclinical involvement, which correlates well with biopsy of the minor labial salivary glands. Salivary gland abnormalities in systemic disease such as sarcoidosis, rheumatoid arthritis, lupus erythematosus, and other collagenvascular disorders may be detected before they result in the clinical manifestaions of Sjoegren's syndrome. Such glands, after initially demonstrating increased trapping in the acute phase, tend to have decreased trapping and failure to discharge pertechnetate in response to an appropriate physiologic stimulus. Increased uptake of gallium-67 citrate often accompanies these findings. Inflammatory parotitis can be suspected when increased perfusion is evident on radionuclide angiography with any agent. The ability of the salivary gland image to detect and categorize mass lesions, which result in focal areas of diminished activity such as tumors, cysts, and most other masses, is disappointing, while its ability to detect and categorize Warthin's tumor, which concentrates pertechnetate, is much more valuable, although not specific.

  2. Study on natural radionuclide activities in meat samples consumed in Sao Paulo City, Brazil

    International Nuclear Information System (INIS)

    Rosa, Mychelle M.L.; Taddei, Maria HelenaT.

    2015-01-01

    Consumption of food is usually the most important route by which natural and artificial radionuclides can enter the human body. An assessment of radionuclide levels in different foods and diets is therefore important to estimate the intake of these radionuclides by man. The contamination by radionuclides can occur via the food chain (soil, root, plant and animal), with emphasis to the long half-life radionuclides, which can also have their transfer through the animal meat. The inclusion of meat in human nutrition is important because it is an excellent source of high quality protein, nutrient related to construction and cell regeneration. This work aims the determination of natural radionuclides ( 234 U, 235 U, 238 U, 228 Th, 230 Th, 232 Th, 226 Ra, 228 Ra, and 210 Pb) in meat samples. Five groups of samples were analyzed, such as cattle meat (beef), fish, pork, poultry, and processed meat, after radiochemical separation followed by alpha or alpha beta spectrophotometry, and total count quantification. The determination of these radionuclides is very important because they are products of the natural decay series of 238 U and 232 Th, being easily found in meat samples. (author)

  3. Study on natural radionuclide activities in meat samples consumed in Sao Paulo City, Brazil

    Energy Technology Data Exchange (ETDEWEB)

    Rosa, Mychelle M.L.; Taddei, Maria HelenaT. [Comissao Nacional de Energia Nuclear (LAPOC/CNEN), Pocos de Caldas, MG (Brazil). Laboratorio de Pocos de Caldas; Avegliano, Roseane P.; Maihara, Vera A., E-mail: mychelle@cnen.gov.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2015-07-01

    Consumption of food is usually the most important route by which natural and artificial radionuclides can enter the human body. An assessment of radionuclide levels in different foods and diets is therefore important to estimate the intake of these radionuclides by man. The contamination by radionuclides can occur via the food chain (soil, root, plant and animal), with emphasis to the long half-life radionuclides, which can also have their transfer through the animal meat. The inclusion of meat in human nutrition is important because it is an excellent source of high quality protein, nutrient related to construction and cell regeneration. This work aims the determination of natural radionuclides ({sup 234}U, {sup 235}U, {sup 238}U, {sup 228}Th, {sup 230}Th, {sup 232}Th, {sup 226}Ra, {sup 228}Ra, and {sup 210}Pb) in meat samples. Five groups of samples were analyzed, such as cattle meat (beef), fish, pork, poultry, and processed meat, after radiochemical separation followed by alpha or alpha beta spectrophotometry, and total count quantification. The determination of these radionuclides is very important because they are products of the natural decay series of {sup 238}U and {sup 232}Th, being easily found in meat samples. (author)

  4. Use of artificial tracers in hydrology

    International Nuclear Information System (INIS)

    1991-05-01

    The IAEA has convened an Advisory Group Meeting with the following objectives: To define the role of artificial radioactive tracers for water tracing in comparison with other non-radioactive tracers. To evaluate the real needs of artificial radioactive tracers in hydrology. To identify the fields for which artificial radioactive tracers are useful as well as those in which they can be substituted by other tracers. To discuss the strategy to be adopted to overcome the difficulties derived from the restrictions on the use of radioactive tracers in hydrology. The meeting was held at IAEA Headquarters from 19 to 22 March 1990, and was attended by 30 participants from 15 Member States. The conclusions and recommendations are that the use of artificial radioactive tracers should be restricted to cases where other tracers cannot be used or do not provide the same quality of information. Tritium, iodine-131, bromine-82, chromium-51 in the form of Cr-EDTA, technetium-99m obtained from 99 Mo-generators and gold-198 as an adsorbable tracer are, practically, the only radionuclides used for water tracing. The use of other radionuclides for this purpose does not appear to be necessary, possible and/or convenient. Refs, figs and tabs

  5. [Use of radionuclides in therapy].

    Science.gov (United States)

    Vucina, J; Han, R

    2001-01-01

    In nuclear medicine therapy is based on deposition of certain doses of ionizing radiation in tumors or organ tissues. Regarding their linear energy transfer (LET) values and relative biological effectiveness (RBE), principal radiotherapeuticals are alpha-, beta-, beta/gamma- or electron-emitters. In principle, to achieve the desired therapeutic effect, a particular radionuclide should exhibit adequate physical, chemical and biological properties. However, considerable efforts are required in selecting an optimal radionuclide for a specific application and then, in the development of methods for its routine production. The paper reviews several aspects of use, properties and production of unsealed radiation sources which are intended to be administered for therapeutic purposes. It covers scientific and practical criteria involved in selecting the radionuclide from medical point of view. The main indications for use of radiotherapeuticals are in oncology and rheumathology. Besides well known, like 32P, 89Sr, 90Y and 131I, several other radionuclides are also listed. Some of them are already in routine use while the others are still under investigation. The main chemical forms of radionuclides and indications are revealed. Particular emphasis is put on the discussion on criteria which a radionuclide should fulfill regarding its physical properties (type, energy, half life, ratio and abundance of the particulate and gamma ray emission). Ideally, they should, together with chemical and biological properties, match with the in-vivo pharmacokinetics and localization of the radionuclide and/or radiopharmaceutical. The trend in modern nuclear medicine is introduction of radionuclides of very specific properties. This, on the other side, opens a question of their availability on the routine basis and at reasonable prices. This matter is also discussed in the present review. Production of radionuclides for therapeutic purposes (as well as those for diagnostics) is performed

  6. National low-level waste management program radionuclide report series, Volume 15: Uranium-238

    International Nuclear Information System (INIS)

    Adams, J.P.

    1995-09-01

    This report, Volume 15 of the National Low-Level Waste Management Program Radionuclide Report Series, discusses the radiological and chemical characteristics of uranium-238 ( 238 U). The purpose of the National Low-Level Waste Management Program Radionuclide Report Series is to provide information to state representatives and developers of low-level radioactive waste disposal facilities about the radiological, chemical, and physical characteristics of selected radionuclides and their behavior in the waste disposal facility environment. This report also includes discussions about waste types and forms in which 238 U can be found, and 238 U behavior in the environment and in the human body

  7. Subject-3: Study on migration of radionuclides released into terrestrial and aquatic environment after nuclear accident

    Energy Technology Data Exchange (ETDEWEB)

    Amano, H.; Matsunaga, T.; Ueno, T.; Nagao, S.; Yanase, N. [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment; Arkhipov, A.N. [Chernobyl Scientific and Technical Center for International Research (Ukraine); Tkachenko, Yu. [The State Enterprise Regional Monitoring and Domestic Control (RADEC) (Unknown)

    2001-03-01

    Subject-3 has been focused on the migration behavior of long-lived radionuclides in the terrestrial surface environment, especially in connection with their chemical and physical forms. Migration behavior of radionuclides is strongly affected with their chemical and physical forms (for example; Gunten and Benes 1995). One of the two categories in Subject-3 consists of migration from surface soils including aging effects of hot particles, plant uptake from contaminated soils, and resuspension of radionuclides. The other is run off by river system, considering the role of organic materials. (author)

  8. National low-level waste management program radionuclide report series, Volume 15: Uranium-238

    Energy Technology Data Exchange (ETDEWEB)

    Adams, J.P.

    1995-09-01

    This report, Volume 15 of the National Low-Level Waste Management Program Radionuclide Report Series, discusses the radiological and chemical characteristics of uranium-238 ({sup 238}U). The purpose of the National Low-Level Waste Management Program Radionuclide Report Series is to provide information to state representatives and developers of low-level radioactive waste disposal facilities about the radiological, chemical, and physical characteristics of selected radionuclides and their behavior in the waste disposal facility environment. This report also includes discussions about waste types and forms in which {sup 238}U can be found, and {sup 238}U behavior in the environment and in the human body.

  9. Graphic display of internal doses from multiple uptakes of radionuclides

    International Nuclear Information System (INIS)

    Wenzel, D.R.

    1976-01-01

    Personnel routinely working in a contaminated area may receive small uptakes of radionuclides. The amount and behavior of the inhaled and/of ingested radionuclides can be established from a bioassay and in vivo measurements. The dose evaluation of the uptake becomes complex when there are several radionuclides involved and when multiple exposures are experienced over a long period of time. A computer is used to calculate the dose and to display graphically the dose received by an organ as it is accumulated along with the projected dose. This paper presents graphic displays of actual multiple internal doses received by a radiation worker and presents the techniques used to calculate and display the doses

  10. Performance analysis of numeric solutions applied to biokinetics of radionuclides

    International Nuclear Information System (INIS)

    Mingatos, Danielle dos Santos; Bevilacqua, Joyce da Silva

    2013-01-01

    Biokinetics models for radionuclides applied to dosimetry problems are constantly reviewed by ICRP. The radionuclide trajectory could be represented by compartmental models, assuming constant transfer rates between compartments. A better understanding of physiological or biochemical phenomena, improve the comprehension of radionuclide behavior in the human body and, in general, more complex compartmental models are proposed, increasing the difficulty of obtaining the analytical solution for the system of first order differential equations. Even with constant transfer rates numerical solutions must be carefully implemented because of almost singular characteristic of the matrix of coefficients. In this work we compare numerical methods with different strategies for ICRP-78 models for Thorium-228 and Uranium-234. The impact of uncertainty in the parameters of the equations is also estimated for local and global truncation errors. (author)

  11. Radionuclide Sensors for Water Monitoring

    International Nuclear Information System (INIS)

    Grate, Jay W.; Egorov, Oleg B.; DeVol, Timothy A.

    2004-01-01

    Radionuclide contamination in the soil and groundwater at U.S. Department of Energy (DOE) sites is a severe problem that requires monitoring and remediation. Radionuclide measurement techniques are needed to monitor surface waters, groundwater, and process waters. Typically, water samples are collected and transported to an analytical laboratory, where costly radiochemical analyses are performed. To date, there has been very little development of selective radionuclide sensors for alpha- and beta-emitting radionuclides such as 90Sr, 99Tc, and various actinides of interest. The objective of this project is to investigate novel sensor concepts and materials for sensitive and selective determination of beta- and alpha-emitting radionuclide contaminants in water. To meet the requirements for loW--level, isotope-specific detection, the proposed sensors are based on radiometric detection. As a means to address the fundamental challenge of the short ranges of beta and alpha particle s in water, our overall approach is based on localization of preconcentration/separation chemistries directly on or within the active area of a radioactivity detector. Automated microfluidics is used for sample manipulation and sensor regeneration or renewal. The outcome of these investigations will be the knowledge necessary to choose appropriate chemistries for selective preconcentration of radionuclides from environmental samples, new materials that combine chemical selectivity with scintillating properties, new materials that add chemical selectivity to solid-state diode detectors, new preconcentrating column sensors, and improved instrumentation and signal processing for selective radionuclide sensors. New knowledge will provide the basis for designing effective probes and instrumentation for field and in situ measurements

  12. Radionuclide Sensors for Water Monitoring

    International Nuclear Information System (INIS)

    Grate, Jay W.; Egorov, Oleg B.; DeVol, Timothy A.

    2001-01-01

    Radionuclide contamination in the soil and groundwater at U.S. Department of Energy (DOE) sites is a severe problem requiring monitoring and remediation. Radionuclide measurement techniques are needed to monitor surface waters, groundwater, and process waters. Typically, water samples are collected and transported to the analytical laboratory where costly radiochemical analyses are performed. To date, there has been very little development of selective radionuclide sensors for alpha- and beta-emitting radionuclides such as 90 Sr, 99 Tc, and various actinides of interest. The objective of this project is to investigate novel sensor concepts and materials for sensitive and selective determination of beta- and alpha-emitting radionuclide contaminants in water. To meet the requirements for low-level, isotope-specific detection, the proposed sensors are based on radiometric detection. As a means to address the fundamental challenge of short ranges of beta and alpha particles in water, our overall approach is based on localization of preconcentration/separation chemistries directly on or within the active area of a radioactivity detector, using automated microfluidics for sample manipulation and sensor regeneration or renewal. The outcome of these investigations will be the knowledge necessary to choose appropriate chemistries for selective preconcentration of radionuclides from environmental samples, new materials that combine chemical selectivity with scintillating properties, new materials that add chemical selectivity to solid-state diode detectors, new preconcentrating column sensors, and improved instrumentation and signal processing for selective radionuclide sensors. New knowledge will provide the basis for designing effective probes and instrumentation for field analytical chemistry

  13. Radionuclide Sensors for Water Monitoring

    International Nuclear Information System (INIS)

    Grate, Jay W.; Egorov, Oleg B.; DeVol, Timothy A.

    2003-01-01

    Radionuclide contamination in the soil and groundwater at U.S. Department of Energy (DOE) sites is a severe problem that requires monitoring and remediation. Radionuclide measurement techniques are needed to monitor surface waters, groundwater, and process waters. Typically, water samples are collected and transported to an analytical laboratory, where costly radiochemical analyses are performed. To date, there has been very little development of selective radionuclide sensors for alpha- and beta-emitting radionuclides such as 90Sr, 99Tc, and various actinides of interest. The objective of this project is to investigate novel sensor concepts and materials for sensitive and selective determination of beta- and alpha-emitting radionuclide contaminants in water. To meet the requirements for low-level, isotope-specific detection, the proposed sensors are based on radiometric detection. As a means to address the fundamental challenge of the short ranges of beta and alpha particles in water, our overall approach is based on localization of preconcentration/separation chemistries directly on or within the active area of a radioactivity detector. Automated microfluidics is used for sample manipulation and sensor regeneration or renewal. The outcome of these investigations will be the knowledge necessary to choose appropriate chemistries for selective preconcentration of radionuclides from environmental samples, new materials that combine chemical selectivity with scintillating properties, new materials that add chemical selectivity to solid-state diode detectors, new preconcentrating column sensors, and improved instrumentation and signal processing for selective radionuclide sensors. New knowledge will provide the basis for designing effective probes and instrumentation for field and in situ measurements

  14. Radionuclide therapy of bone metastases

    International Nuclear Information System (INIS)

    Palmedo, H.; Bucerius, J.

    2008-01-01

    Many tumors (like prostate- and breast cancer) induce osseous metastases that need to be treated. Bone targeted radionuclide therapy should be performed at an early stage in patients with painful bone metastases and scintigraphically positive lesions. The combination of external beam irradiation and systemic administration of radionuclides is often advantageous and can be performed without clinical problems. In patients with hormone-refractory prostate cancer and bone metastases, radionuclide therapy is increasingly performed as antitumor treatment for asymptomatic patients in clinical trials. By randomised, controlled clinical phase-II studies, it has been shown that new therapy regimens can prolong the progression-free interval and overall survival. New protocols that have been proposed represent the simultaneous application of chemotherapy and radionuclides. Side effects of such protocols are kept within a low toxicity level by reducing the dose of the chemotherapeutic agent (low-dose-chemotherapy). This combined therapy approach, however, is able to generate a radiosensitive state in the tumor cells resulting in an increased tumoricide efficiency of radionuclides. A different, innovative approach is the administration of multiple radionuclide injections at defined time intervals aiming at killing tumor cells with higher radiation doses. Side effects of these new treatment regimens can be scored as moderate. Consequently, in hormone-refractory prostate cancer patients, such new protocols should be considered as an alternative treatment option after standardised therapy regimens have been accomplished. In this situation, extensive experience for treating and selecting appropriate patients is crucial. A randomised pase-III study for the prove of an increased progression-free interval and overall-survival by radionuclide therapy is still missing. (orig.)

  15. Artificial Gravity

    CERN Document Server

    Clément, Gilles

    2007-01-01

    Protecting the health, safety, and performance of exploration-class mission crews against the physiological deconditioning resulting from long-term weightlessness during transit and long-term reduced gravity during surface operations will require effective, multi-system countermeasures. Artificial gravity, which would replace terrestrial gravity with inertial forces generated by rotating the transit vehicle or by short-radius human centrifuge devices within the transit vehicle or surface habitat, has long been considered a potential solution. However, despite its attractiveness as an efficient

  16. Artificial graphites

    International Nuclear Information System (INIS)

    Maire, J.

    1984-01-01

    Artificial graphites are obtained by agglomeration of carbon powders with an organic binder, then by carbonisation at 1000 0 C and graphitization at 2800 0 C. After description of the processes and products, we show how the properties of the various materials lead to the various uses. Using graphite enables us to solve some problems, but it is not sufficient to satisfy all the need of the application. New carbonaceous material open application range. Finally, if some products are becoming obsolete, other ones are being developed in new applications [fr

  17. Calibration of the radionuclide logging system germanium detector

    International Nuclear Information System (INIS)

    Randall, R.R.

    1994-01-01

    High resolution passive gamma-ray logging, high resolution gamma-ray-emitting nuclides in areas surrounding underground waste disposal facilities on the US Department of Energy's Hanford Site. Gamma-ray source concentrations are derived from log data by calculations that employ the calibration factors and correction functions described in this report. Calibration data were collected with a Radionuclide Logging System. Analyses of the calibration data established: (1) calibration factors for potassium, uranium, and thorium, and (2) a calibration function that permits assessments of cesium-137, cobalt-60, and other artificial nuclides not represented in the calibration models

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

    International Nuclear Information System (INIS)

    Ballestra, S.; Lopez, J.J.; Gastaud, J.; Parsi, P.; Vas, D.; Noshkin, V.

    1991-08-01

    The results of an intercomparison exercise on a Pacific Ocean sediment sample, IAEA-368, designed for the determination of artificial and natural radionuclides levels, are reported. The data from 89 laboratories representing 37 countries have been evaluated. The following are the recommended values, with confidence intervals, for 60 Co, 155 Eu, 210 7Pb, 226 Ra, 238 U, 238 Pu and 239+240 Pu (Reference date: 1 January 1990). Information values for 40 K, 90 Sr, 137 Cs, 228 Th, 230 Th, 232 Th, 234 U, 235 U and 241 Am are also reported. (author)

  19. Radionuclide injury to the lung

    International Nuclear Information System (INIS)

    Dagle, G.E.; Sanders, C.L.

    1984-01-01

    Radionuclide injury to the lung has been studied in rats, hamsters, dogs, mice and baboons. Exposure of the lung to high dose levels of radionuclides produces a spectrum of progressively more severe functional and morphological changes, ranging from radiation pneumonitis and fibrosis to lung tumors. These changes are somewhat similar for different species. Their severity can be related to the absorbed radiation dose (measured in rads) produced by alpha, beta or gamma radiation emanating from various deposited radionuclides. The chemicophysical forms of radionuclides and spatial-temporal factors are also important variables. As with other forms of injury to the lung, repair attempts are highlighted by fibrosis and proliferation of pulmonary epithelium. Lung tumors are the principal late effect observed in experimental animals following pulmonary deposition of radionuclides at dose levels that do not result in early deaths from radiation pneumonitis or fibrosis. The predominant lung tumors described have been of epithelial origin and have been classified, in decreasing frequency of occurrence, as adenocarcinoma, bronchioloalveolar carcinoma, epidermoid carcinomas and combined epidermoid and adenocarcinoma. Mesothelioma and fibrosarcoma have been observed in rats, but less commonly in other species. Hemangiosarcomas were frequently observed in dogs exposed to beta-gamma emitters, and occasionally in rats exposed to alpha emitters. These morphologic changes in the lungs of experimental animals were reviewed and issues relevant to the prediction of human hazards discussed. 88 references

  20. Inverse problem in radionuclide transport

    International Nuclear Information System (INIS)

    Yu, C.

    1988-01-01

    The disposal of radioactive waste must comply with the performance objectives set forth in 10 CFR 61 for low-level waste (LLW) and 10 CFR 60 for high-level waste (HLW). To determine probable compliance, the proposed disposal system can be modeled to predict its performance. One of the difficulties encountered in such a study is modeling the migration of radionuclides through a complex geologic medium for the long term. Although many radionuclide transport models exist in the literature, the accuracy of the model prediction is highly dependent on the model parameters used. The problem of using known parameters in a radionuclide transport model to predict radionuclide concentrations is a direct problem (DP); whereas the reverse of DP, i.e., the parameter identification problem of determining model parameters from known radionuclide concentrations, is called the inverse problem (IP). In this study, a procedure to solve IP is tested, using the regression technique. Several nonlinear regression programs are examined, and the best one is recommended. 13 refs., 1 tab

  1. Comportamento de Litopenaeus vannamei (Boone (Crustacea, Decapoda, Penaeidae em função da oferta do alimento artificial nas fases clara e escura do período de 24 horas Behavior of Litopenaeus vannamei (Boone (Crustacea, Decapoda, Penaeidae in relation to artificial food offer along light and dark phases in a 24 h period

    Directory of Open Access Journals (Sweden)

    Cibele S. Pontes

    2005-09-01

    Full Text Available A escassez de dados acerca do comportamento do camarão marinho Litopenaeus vannamei (Boone, 1931 relacionado ao alimento artificial ofertado em comedouros poderá induzir a uma alimentação inadequada, aumentando a relação custo/benefício e os impactos ambientais potenciais do seu cultivo. Objetivando fornecer subsídios para a melhoria do manejo alimentar praticado nas fazendas, foram desenvolvidos estudos comportamentais utilizando 64 juvenis de L. vannamei (7,57 ± 1,01 g, submetidos a fotoperíodo artificial, metade deles em ciclo invertido, para observação das suas atividades durante as fases clara e escura. A ração foi oferecida em intervalos pré-estabelecidos, registrando-se antes e depois da oferta: exploração, natação, alimentação e inatividade (focal instantâneo. A natação ocorreu preferencialmente durante a fase escura. A alimentação foi mais elevada na primeira meia hora posterior à oferta, com ênfase nos horários da fase clara. O alimento artificial atuou, em ambas as fases, como um indutor da exploração do substrato, tornando os camarões mais ativos em todos os horários posteriores à sua oferta.The few data on the marine shrimp Litopenaeus vannamei (Boone, 1931 behavior related to artificial food offer in feeding trays may result an inadequate feeding by the animal, increasing the cost/benefit relation in shrimp culture and its potential environmental impact. In order to provide tools for optimizing feeding management in shrimp farms, a behavioral study was developed, using 64 L. vannamei juveniles (7,57 ± 1,01 g. They were submitted to artificial photoperiods, half of them in reversed cycle, in order to register their behavior during light and dark phases. In established intervals, the following activities were registered before and after food exposition: exploration, swimming, feeding and inactivity (instantaneous sampling. Swimming occurred mostly during the dark phase. Feeding time was higher in

  2. Binding of radionuclides to proteins in fish

    International Nuclear Information System (INIS)

    Suzuki, Yuzuru

    1981-01-01

    Radioisotope tracer experiments on binding of radionuclides to proteins in fish were carried out in order to gain further information on biochemical behavior of radionuclides in marine fish. The radionuclides, which were bound to proteins in fish through sea water and food, were extracted with a Trisacetate buffer solution and separated by gel filtration on Sephadex G-75. Most of 137 Cs in the fish liver were bound only to a peptide with a molecular weight of 1,100 - 1,300. The most remarkable feature of 60 Co in the profiles of the gel filtration was the presence of two clear radioactivity pearks and the radioactivity appeared to transfer from a low molecular weight protein to a high molecular weight protein in the case of the uptake, and the reverse phenomenon was observed in the case of the excretion. Therefore, this suggested that these proteins had each inherent turnover rate for 60 Co. The profiles of the gel filtration of 65 Zn varied widely among species of fish, tissues or organs even in the same fish and pathways of the uptake. 125 I was bound to a relatively low molecular weight substance in cultured eel, however, the binding of 125 I to a protein with higher molecular weight was observed in the eel head including thyroid gland marked through food, and this protein was estimated to be thyroglobulin with molecular weight of 670,000. Although 95 Nb, 144 Ce- 144 Pr and 106 Ru- 106 Rh probably have no biological function in fish, it was apparently found to be organically bound in tissues or organs of the marine fish. (author)

  3. Natural radionuclides in Brazilian underground mines

    International Nuclear Information System (INIS)

    Santos, Talita de Oliveira

    2015-01-01

    Rock, soil and water contain 238 U and 232 Th and their decay products. The distribution of these radionuclides differs in terms of activity concentration depending on the mineral type and origin. All ore processing releases long and short half-life radionuclides, mainly radon and its progeny. It is important to monitor this gas and its decay products in underground mines in order to assess the radiological hazards of the exposed workers. On this concern, the present work outlines the characterization of brazilian underground mines with relation to natural radionuclides, specially radon and its progeny. The radon concentration was measured by using E-PERM Electrets Ion Chamber (Radelec), AlphaGUARD (Saphymo GmbH) and CR-39 (Landauer) track etch detectors. The radon progeny was determined by using DOSEman detector. The equilibrium state between radon and its progeny was calculated. Based on these data, the total effective dose for miners was estimated. Moreover, the contribution from the main sources to the radon level inside mines was evaluated. For this, the following detectors were used: measurements of radon concentrations in soil gas were carried out by using AlphaGUARD detector; 226 Ra ( 214 Bi), 232 Th e 40 K specific activity in ore and soil samples were determined by using gamma-ray spectrometry HPGe detector (Canberra); and radon concentration in groundwater samples was performed by using RAD7 (Durridge Inc.). The radon concentration ranged from 113 to 8171 Bq.m -3 and the Equilibrium Equivalent Concentration varied from 76 to 1174 Bq.m -3 . The equilibrium factor mean value was 0.4 (0.2 -0.7). The workers estimated total effective dose ranged from 1 to 22 mSv.a -1 (mean 10 mSv.a -1 ). Therefore, results show the importance to assess continually and permanently the radon and its progeny behavior and the need to adopt safety measurements against natural radiation in underground mines environment. (author)

  4. Radionuclide Therapy for Neuroendocrine Tumors.

    Science.gov (United States)

    Cives, Mauro; Strosberg, Jonathan

    2017-02-01

    Peptide receptor radionuclide therapy (PRRT) is a form of systemic radiotherapy that allows targeted delivery of radionuclides to tumor cells expressing high levels of somatostatin receptors. The two radiopeptides most commonly used for PRRT, 90 Y-DOTATOC and 177 Lu-DOTATATE, have been successfully employed for more than a decade for the treatment of advanced neuroendocrine tumors (NETs). Recently, the phase III, randomized NETTER-1 trial has compared 177 Lu-DOTATATE versus high-dose octreotide LAR in patients with progressive, metastatic midgut NETs, demonstrating exceptional tolerability and efficacy. This review summarizes recent developments in the field of radionuclide therapy for gastroenteropancreatic and lung NETs and considers possible strategies to further enhance its clinical efficacy.

  5. Method of preparing radionuclide doses

    International Nuclear Information System (INIS)

    Kuperus, J.H.

    1987-01-01

    A method is described of preparing aliquot dosea of a tracer material useful in diagnostic nuclear medicine comprising: storing discrete quantities of a lyophilized radionuclide carrier in separate tubular containers from which air and moisture is excluded, selecting from the tubular containers a container in which is stored a carrier appropriate for a nuclear diagnostic test to be performed, interposing the selected container between the needle and the barrel of a hypodermic syringe, and drawing a predetermined amount of a liquid containing a radionuclide tracer in known concentration into the hypodermic syringe barrel through the hypodermic needle and through the selected container to dissolve the discrete quantity of lyophilized carrier therein to combine the carrier with the radionuclide tracer to form an aliquot dose of nuclear diagnostic tracer material, as needed

  6. Radionuclide Distribution in the Soil on the Stabatishkes Site in the Vicinity of the Ignalina NPP

    Directory of Open Access Journals (Sweden)

    Jevgenij Aliončik

    2011-02-01

    Full Text Available A near surface repository for low and intermediate-level short-lived radioactive waste will be built on the Stabatiškės site in the vicinity of Ignalina NPP during decommissioning works. The reservoir can also be used for the waste stored in the temporary repositories of the Ignalina NPP. Engineering and nature protective barriers are used in the repository for radioactive waste, however, radionuclides can spread into the environment, extend in the biosphere and cause (define the external power light exposure of the environment due to the natural and premature (prescheduled degradation of the engineering barriers of the repository. The properties of the soil (acidity, quantity of organic substances, humidity are being investigated for estimating the possible migration and dispersion of radionuclides. The activity of radionuclides in the soil is also estimated before building the repository. Natural and artificial radionuclides make the pollution of the soil, and therefore the accumulation and vertical migration of artificial (137Cs, 60Co and natural (226Ra, 232Th, 40K radionuclides are being researched in the soil on the Stabatiškės site.Article in Lithuanian

  7. Radionuclide migration through fractured granite

    International Nuclear Information System (INIS)

    Grondin, D.M.; Vandergraaf, T.T.; Drew, D.J.

    1988-01-01

    Radionuclide migration has been studied in natural fractures in granite blocks of up to 30 cm in length. Results are reported for four migration experiments involving synthetic groundwaters containing tritiated water, 95m Tc, 75 Se, 137 Cs, or 60 Co-labelled natural colloids, which were injected into the fractures at flow rates of 0.4-0.45 mL/h, giving residence times in the fractures of up to 15 h. Also presented are the results of the post-experiment analyses, including an autoradiograph of one of the fracture surfaces, and the spatial distribution of the sorbed radionuclides determined by γ-scanning and selective chemical extractions

  8. Producing new radionuclides for medicine

    International Nuclear Information System (INIS)

    Michaut, C.

    2009-01-01

    The Arronax cyclotron, a new particle accelerator dedicated to the production of radionuclides for medicine and research has been commissioned in Nantes (France). Because of its unique features: an energy of 70 MeV and an intensity of 750 μA, Arronax will produce radionuclides that can not be produce in present cyclotrons. Among others it will produce Strontium-82 and Germanium-68 that are the precursors for Rubidium-82 and Gallium-68 respectively. 20 per cent of the research works will be dedicated to other domains like radioactive wastes, the radiation biological damage and the radiation damage on electronic devices. (A.C.)

  9. Radionuclide techniques for brain imaging

    International Nuclear Information System (INIS)

    Cowan, R.J.; Moody, D.M.

    1984-01-01

    Over the past decade, many of the prime indications for radionuclide brain scanning have become instead indications for CCT, and nuclear medicine studies of the brain have assumed more of a complementary, supportive role. However, there is great promise for improvement in central nervous system radionuclide applications with advances anticipated in both radiopharmaceuticals and instrumentation. Nuclear medicine is continuing to function as a powerful research tool and, in the relatively near future, may regain its role as a major clinical test of the central nervous system

  10. Artificial rheotaxis.

    Science.gov (United States)

    Palacci, Jérémie; Sacanna, Stefano; Abramian, Anaïs; Barral, Jérémie; Hanson, Kasey; Grosberg, Alexander Y; Pine, David J; Chaikin, Paul M

    2015-05-01

    Motility is a basic feature of living microorganisms, and how it works is often determined by environmental cues. Recent efforts have focused on developing artificial systems that can mimic microorganisms, in particular their self-propulsion. We report on the design and characterization of synthetic self-propelled particles that migrate upstream, known as positive rheotaxis. This phenomenon results from a purely physical mechanism involving the interplay between the polarity of the particles and their alignment by a viscous torque. We show quantitative agreement between experimental data and a simple model of an overdamped Brownian pendulum. The model notably predicts the existence of a stagnation point in a diverging flow. We take advantage of this property to demonstrate that our active particles can sense and predictably organize in an imposed flow. Our colloidal system represents an important step toward the realization of biomimetic microsystems with the ability to sense and respond to environmental changes.

  11. Report on the intercomparison run IAEA-307 radionuclides in sea plant

    International Nuclear Information System (INIS)

    Veglia, A.; Ballestra, S.; Vas, D.

    1989-10-01

    The results of an intercomparison exercise on a Mediterranean Sea plant sample, coded as IAEA-307, designed for the determination of artificial and natural radionuclide levels, are reported. This sample was collected along the shore from the vicinity of the Principality of Monaco in October 1986. The data from 66 laboratories representing 31 countries have been evaluated. The most frequently measured radionuclides: 106 Ru, 110m Ag, 134 Cs, 137 Cs, 238 Pu, 239+240 Pu, 241 Am, 40 K and 226 Ra. 10 refs, 38 tabs

  12. Report on the intercomparison run IAEA-352 radionuclides in tuna fish flesh

    International Nuclear Information System (INIS)

    Ballestra, S.; Vas, D.; Lopez, J.J.; Noshkin, V.

    1990-08-01

    The results of an intercomparison exercise on a sample of tuna fish flesh from the Mediterranean Sea, IAEA-352, designed for the determination of artificial and natural radionuclides levels, are reported. The data from 63 laboratories from 31 countries have been evaluated. The following are the recommended values, with confidence intervals, for the most frequently measured radionuclides (Reference data: 1 January 1989): 137 Cs 2.7 Bq kg -1 , 90 Sr 0.2 Bq Kg -1 , 40 K 391 Bq Kg -1 , 210 Pb 0.6 Bq Kg -1 , 210 Po 2.2 Bq Kg -1 . Tabs

  13. Determination of alpha radionuclides in fish

    International Nuclear Information System (INIS)

    Pernicka, L.; Matel, L.; Rosskopfova, O.

    2001-01-01

    In atmospheric water, external water and undercurrent the occurrence of radionuclides is usual. It is an important factor of quality of the environment. Plants ingest radionuclides from water and with they everyone. And it arises radioactivity infest food-chain. Radiotoxicity of this radionuclides is very deer sometimes. The sensitive radiochemical procedures for their determination are necessarily important. The poster presents the combined procedure used at our laboratory for determination of alpha radionuclides in biological samples. (authors)

  14. Inflatable artificial sphincter

    Science.gov (United States)

    ... procedures to treat urine leakage and incontinence include: Anterior vaginal wall repair Urethral bulking with artificial material ... urinary incontinence Images Inflatable artificial sphincter Anal sphincter anatomy Inflatable artificial sphincter - series References Adams MC, Joseph ...

  15. Daily intakes of radionuclides in Japanese standard diets

    International Nuclear Information System (INIS)

    Terada, H.; Sugiyama, H.; Iijima, I.; Isomura, K.; Kobayashi, J.

    2005-01-01

    Daily intakes of radionuclides in Japanese standard diets were investigated. Food samples were collected from 9 cities of Japan using the market basket method according to the reports of National Nutrition Study in Japan (2000). These samples were categorized the following 14 groups; Group l: rice, rice products; Group 2: grain, seeds, potato; Group 3: sugar, confectionery; Group 4: oils and fats; Group 5: beans; Group 6: fruits; Group 7: green and yellow vegetables; Group 8: other vegetables; mushrooms, seaweed; Group 9: seasoning, drinks; Group 10: fish and shellfish; Group 11: meat, eggs; Group 12: milk, milk products; Group 13: other foods; and Group 14 was drinking water. Each group was homogenized separately after cooking the food materials. Determination of radioactivity was performed by gamma ray spectrometry. The only artificial radionuclide detected from gamma ray spectrometry was 137 CS, and its concentrations of each sample were almost less than 0.1 Bq/kg. Strontium-90 and 238 U concentrations of the total diet samples were analyzed with chemical separation. The concentrations of 90 Sr and 238 U were in the range of 0.013-0.031 Bq/kg, 0.0039-0.014 Bq/kg respectively, and a large difference was not found among the concentrations of each nuclide in 9 cities. We would like to estimate internal radiation dose to Japanese population from the dietary intakes of these radionuclides.

  16. Uptake of radionuclides from soil

    International Nuclear Information System (INIS)

    Keller, C.

    1980-01-01

    The field studies by the KFA Juelich to determine the transfer factors for the radionuclides 90 Sr, 137 Cs, 60 Co and 54 Mn are reported about. Potatoes, sugar beets, winter wheat, spring barley, clover, alfalfa and ray grass, and in some cases also field vegetables were used. The influence of soil properties on the transfer factors is investigated. (MG) [de

  17. Tumor Immunotargeting Using Innovative Radionuclides

    Directory of Open Access Journals (Sweden)

    Françoise Kraeber-Bodéré

    2015-02-01

    Full Text Available This paper reviews some aspects and recent developments in the use of antibodies to target radionuclides for tumor imaging and therapy. While radiolabeled antibodies have been considered for many years in this context, only a few have reached the level of routine clinical use. However, alternative radionuclides, with more appropriate physical properties, such as lutetium-177 or copper-67, as well as alpha-emitting radionuclides, including astatine-211, bismuth-213, actinium-225, and others are currently reviving hopes in cancer treatments, both in hematological diseases and solid tumors. At the same time, PET imaging, with short-lived radionuclides, such as gallium-68, fluorine-18 or copper-64, or long half-life ones, particularly iodine-124 and zirconium-89 now offers new perspectives in immuno-specific phenotype tumor imaging. New antibody analogues and pretargeting strategies have also considerably improved the performances of tumor immunotargeting and completely renewed the interest in these approaches for imaging and therapy by providing theranostics, companion diagnostics and news tools to make personalized medicine a reality.

  18. Tumor immunotargeting using innovative radionuclides.

    Science.gov (United States)

    Kraeber-Bodéré, Françoise; Rousseau, Caroline; Bodet-Milin, Caroline; Mathieu, Cédric; Guérard, François; Frampas, Eric; Carlier, Thomas; Chouin, Nicolas; Haddad, Ferid; Chatal, Jean-François; Faivre-Chauvet, Alain; Chérel, Michel; Barbet, Jacques

    2015-02-11

    This paper reviews some aspects and recent developments in the use of antibodies to target radionuclides for tumor imaging and therapy. While radiolabeled antibodies have been considered for many years in this context, only a few have reached the level of routine clinical use. However, alternative radionuclides, with more appropriate physical properties, such as lutetium-177 or copper-67, as well as alpha-emitting radionuclides, including astatine-211, bismuth-213, actinium-225, and others are currently reviving hopes in cancer treatments, both in hematological diseases and solid tumors. At the same time, PET imaging, with short-lived radionuclides, such as gallium-68, fluorine-18 or copper-64, or long half-life ones, particularly iodine-124 and zirconium-89 now offers new perspectives in immuno-specific phenotype tumor imaging. New antibody analogues and pretargeting strategies have also considerably improved the performances of tumor immunotargeting and completely renewed the interest in these approaches for imaging and therapy by providing theranostics, companion diagnostics and news tools to make personalized medicine a reality.

  19. Radionuclide migration studies in soil

    International Nuclear Information System (INIS)

    Marumo, J.T.

    1989-01-01

    In this work a brief description about retention and migration parameters of radionuclides in soil, including main methods to determine the distribution coefficient (K) are given. Some of several factors that can act on the migration are also mentioned. (author) [pt

  20. 100 Years of radionuclide metrology

    International Nuclear Information System (INIS)

    Judge, S.M.; Arnold, D.; Chauvenet, B.; Collé, R.; De Felice, P.; García-Toraño, E.; Wätjen, U.

    2014-01-01

    The discipline of radionuclide metrology at national standards institutes started in 1913 with the certification by Curie, Rutherford and Meyer of the first primary standards of radium. In early years, radium was a valuable commodity and the aim of the standards was largely to facilitate trade. The focus later changed to providing standards for the new wide range of radionuclides, so that radioactivity could be used for healthcare and industrial applications while minimising the risk to patients, workers and the environment. National measurement institutes responded to the changing demands by developing new techniques for realising primary standards of radioactivity. Looking ahead, there are likely to be demands for standards for new radionuclides used in nuclear medicine, an expansion of the scope of the field into quantitative imaging to facilitate accurate patient dosimetry for nuclear medicine, and an increasing need for accurate standards for radioactive waste management and nuclear forensics. - Highlights: • The driving forces for the development of radionuclide metrology. • Radium standards to facilitate trade of this valuable commodity in the early years. • After 1950, focus changes to healthcare and industrial applications. • National Measurement Institutes develop new techniques, standards, and disseminate the best practice in measurement. • Challenges in nuclear medicine, radioactive waste management and nuclear forensics

  1. Chemistry and analysis of radionuclides

    CERN Document Server

    Lehto, Jukka

    2010-01-01

    Written by chemists for chemists, this is a comprehensive guide to the important radionuclides as well as techniques for their separation and analysis. It introduces readers to the important laboratory techniques and methodologies in the field, providing practical instructions on how to handle nuclear waste and radioactivity in the environment.

  2. The uptake of radionuclides from inadvertent consumption of soil by grazing animals

    International Nuclear Information System (INIS)

    Green, N.; Dodd, N.J.

    1988-01-01

    Investigations of the transfer to man of artificially-produced radionuclides through food chains have shown that the inadvertent consumption of soil by grazing animals can give variations in estimates of transfer coefficients, especially for radionuclides that are poorly absorbed by plant roots. Even small masses of soil adhering to herbage or directly ingested can make a significant contribution to the intake inventory in terms of activity. Although the activity concentrations of soil-contaminated herbage are elevated, the radionuclides associated with the soil may not necessarily be in a form which is easily absorbed by the animal. Attempts must be made, therefore, to quantify soil intake and the subsequent radionuclide uptake by this mechanism. A field investigation of the uptake of radionuclides by farm animals grazing near the Sellafield nuclear reprocessing plant has been pursued. The aims of the study were to estimate the transfer to muscle and other tissues. This paper describes the methods used to estimate both the soil intake and the consequent availability of radionuclides associated with the soil. The measurements were used to evaluate the contribution to tissue content of inadvertent consumption of soil by cows and sheep. 10 refs.; 2 tabs

  3. Improving cancer treatment with cyclotron produced radionuclides

    Energy Technology Data Exchange (ETDEWEB)

    Larson, S.M.; Finn, R.D.

    1992-08-04

    Our goal is to improve the scientific basis for tumor diagnosis, treatment and treatment follow-up based on the use of cyclotron produced radiotracers in oncology. The grant includes 3 interactive components: Radiochemistry/Cyclotron; Pharmacology; and Immunology. The radiochemistry group seeks to develop innovative cyclotron targetry, radiopharmaceuticals, and radiolabeled antibodies, which are then used to assess important unanswered questions in tumor pharmacology and immunology. Examples include selected positron emitting radionuclides, such as Iodine-124, and Ga-66; I-124, I-123, I-131 labeled iododeoxyuridine, C-11 colchicine, and antimetabolites, like C-11 methotrexate; and radiolabeled antibodies, 3F8, M195, A33, and MRK16 for application in the pharmacology and immunology projects. The pharmacology program studies tumor resistance to chemotherapy, particularly the phenomenon of multidrug resistance and the relationship between tumor uptake and retention and the tumor response for anti-metabolite drugs. The immunology program studies the physiology of antibody localization at the tissue level as the basis for novel approaches to improving tumor localization such as through the use of an artificial lymphatic system which mechanically reduces intratumoral pressures in tumors in vivo. Quantitative imaging approaches based on PET and SPECT in radioimmunotherapy are studied to give greater insight into the physiology of tumor localization and dosimetry.

  4. Improving cancer treatment with cyclotron produced radionuclides

    International Nuclear Information System (INIS)

    Larson, S.M.; Finn, R.D.

    1992-01-01

    Our goal is to improve the scientific basis for tumor diagnosis, treatment and treatment follow-up based on the use of cyclotron produced radiotracers in oncology. The grant includes 3 interactive components: Radiochemistry/Cyclotron; Pharmacology; and Immunology. The radiochemistry group seeks to develop innovative cyclotron targetry, radiopharmaceuticals, and radiolabeled antibodies, which are then used to assess important unanswered questions in tumor pharmacology and immunology. Examples include selected positron emitting radionuclides, such as Iodine-124, and Ga-66; I-124, I-123, I-131 labeled iododeoxyuridine, C-11 colchicine, and antimetabolites, like C-11 methotrexate; and radiolabeled antibodies, 3F8, M195, A33, and MRK16 for application in the pharmacology and immunology projects. The pharmacology program studies tumor resistance to chemotherapy, particularly the phenomenon of multidrug resistance and the relationship between tumor uptake and retention and the tumor response for anti-metabolite drugs. The immunology program studies the physiology of antibody localization at the tissue level as the basis for novel approaches to improving tumor localization such as through the use of an artificial lymphatic system which mechanically reduces intratumoral pressures in tumors in vivo. Quantitative imaging approaches based on PET and SPECT in radioimmunotherapy are studied to give greater insight into the physiology of tumor localization and dosimetry

  5. Dynamic Effects of Tank Waste Aging on Radionuclide-Complexant Interactions - Final Report - 10/01/1997 - 10/01/2000

    International Nuclear Information System (INIS)

    Chamberlin, Rebecca M.; Arterburn, Jeffrey B.

    2000-01-01

    The long-range objective of this project is to provide a scientific basis for safely processing high-level nuclear tanks wastes for disposal. Our goals are to identify a means to prepare realistic simulant formulations for complexant-containing Hanford tank wastes, and then use those simulants to determine the relative importance of various organic complexants and their breakdown products on the partitioning of important radionuclides. The harsh chemical and radiolytic environment in high-level waste tanks alters both the organic complexants and the metal species, producing radionuclide-chelator complexes that resist standard separation methods. A detailed understanding of the complexation reactions of the key radionuclides in tank wastes would allow for reliable, science-based solutions for high-level waste processing, but a key problem is that tank waste samples are exceedingly difficult to obtain, transport and handle in the laboratory. In contrast, freshly-prepared simulated wastes are safe and readily obtained, but they do not reproduce the partitioning behavior of actual tank waste samples. For this project, we will first artificially age complexant-containing tank waste simulants using microwave, ultrasound, and photolysis techniques that can be applied in any standard laboratory. The aged samples will be compared to samples of actual Hanford tank wastes to determine the most realistic aging method, on the basis of the organic fragments present, and the oxidation states and partitioning behavior of important radionuclides such as 90Sr, 99Tc, and 239Pu. Our successful completion of this goal will make it possible for scientists in academic and industrial laboratories to address tank waste remediation problems without the enormous costs and hazards associated with handling actual tank waste samples. Later, we will use our simulant aging process to investigate the relative effects of chelator degradation products on the partitioning of important radionuclides

  6. Modeling Radionuclide Transport in Clays

    Energy Technology Data Exchange (ETDEWEB)

    Zheng, Liange [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Li, Lianchong [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Rutqvist, Jonny [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Liu, Hui -Hai [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Birkholzer, Jens [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2012-05-01

    Clay/shale has been considered as potential host rock for geological disposal of high-level nuclear waste throughout the world, because of its low permeability, low diffusion coefficient, high retention capacity for radionuclides, and capability to self-seal fractures induced by tunnel excavation. For example, Callovo-Oxfordian argillites at the Bure site, France (Fouche et al., 2004), Toarcian argillites at the Tournemire site, France (Patriarche et al., 2004), Opalinus Clay at the Mont Terri site, Switzerland (Meier et al., 2000), and Boom clay at the Mol site, Belgium (Barnichon and Volckaert, 2003) have all been under intensive scientific investigation (at both field and laboratory scales) for understanding a variety of rock properties and their relationships to flow and transport processes associated with geological disposal of nuclear waste. Clay/shale formations may be generally classified as indurated or plastic clays (Tsang and Hudson, 2010). The latter (including Boom clay) is a softer material without high cohesion; its deformation is dominantly plastic. During the lifespan of a clay repository, the repository performance is affected by complex thermal, hydrogeological, mechanical, chemical (THMC) processes, such as heat release due to radionuclide decay, multiphase flow, formation of damage zones, radionuclide transport, waste dissolution, and chemical reactions. All these processes are related to each other. An in-depth understanding of these coupled processes is critical for the performance assessment (PA) of the repository. These coupled processes may affect radionuclide transport by changing transport paths (e.g., formation and evolution of excavation damaged zone (EDZ)) and altering flow, mineral, and mechanical properties that are related to radionuclide transport. While radionuclide transport in clay formation has been studied using laboratory tests (e,g, Appelo et al. 2010, Garcia-Gutierrez et al., 2008, Maes et al., 2008), short-term field

  7. 5-7 Year Old Children's Conceptions of Behaving Artifacts and the Influence of Constructing Their Behavior on the Development of Theory of Mind (ToM and Theory of Artificial Mind (ToAM

    Directory of Open Access Journals (Sweden)

    Karen Spektor-Precel

    2015-12-01

    Full Text Available Nowadays, we are surrounded by artifacts that are capable of adaptive behavior, such as electric pots, boiler timers, automatic doors, and robots. The literature concerning human beings’ conceptions of “traditional” artifacts is vast, however, little is known about our conceptions of behaving artifacts, nor of the influence of the interaction with such artifacts on cognitive development, especially among children. Since these artifacts are provided with an artificial “mind,” it is of interest to assess whether and how children develop a Theory of Artificial Mind (ToAM which is distinct from their Theory of Mind (ToM. The study examined a new theoretical scheme named ToAM (Theory of Artificial Mind by means of qualitative and quantitative methodology among twenty four 5-7 year old children from central Israel. It also examined the effects of interacting with behaving artifacts (constructing versus observing the robot’s behavior using the “RoboGan” interface on children’s development of ToAM and their ToM and looked for conceptions that evolve among children while interacting with behaving artifacts which are indicative of the acquisition of ToAM. In the quantitative analysis it was found that the interaction with behaving artifacts, whether as observers or constructors and for both age groups, brought into awareness children’s ToM as well as influenced their ability to understand that robots can behave independently and based on external and environmental conditions. In the qualitative analysis it was found that participating in the intervention influenced the children’s ToAM for both constructors and for the younger observer. Engaging in building the robot’s behavior influenced the children’s ability to explain several of the robots’ behaviors, their understanding of the robot’s script-based behavior and rule-based behavior and the children’s metacognitive development. The theoretical and practical importance of

  8. Status report on radionuclide transfer

    International Nuclear Information System (INIS)

    1980-01-01

    At the suggestion of the Federal Minstry of the Interior, in June 1978, a group of scientists from several institutions who are active in the field of radionuclide transfer or are interested in these problems got together. During the discussions of the work team, especially the transfer soil/plants was emphasized. Then the work team set up a status report on the transfer of the radionuclides relevant in the sense of the radiation protection act. The nuclides H 3 and C14, the isotopes of the Sr, J, and Cs, Tc99, the so-called corrosion nuclides Mn54, Fe59, co-isotopes and Zn65, and isotopes of Pu, Am, and Cm were regarded as important for a possible radiation exposition. Recent investigations revealed that also the natural radionuclides Ra226, Po210, and Pb210 should be covered by the investigations. The goal of this status report is to present the level of knowledge on the transfer of these radionuclides to man in a brief form, giving hints at the most important literature. It was requested by the Federal Ministry of the Interior, as fas as possible, to indicate transfer factors which are necessary for the radio-occology act to be decreed according to Para. 45 of the radiation protection act. Another goal of the report was to show the gap in the knowledge on the radio nuclide transfer. This was thought to help to create a basis for the decisions of the Federal Ministry concerning the support of other investigation projects in the field of transfer of radionuclides. (orig./MG) [de

  9. Conditions and processes affecting radionuclide transport

    Science.gov (United States)

    Simmons, Ardyth M.; Neymark, Leonid A.

    2012-01-01

    Characteristics of host rocks, secondary minerals, and fluids would affect the transport of radionuclides from a previously proposed repository at Yucca Mountain, Nevada. Minerals in the Yucca Mountain tuffs that are important for retarding radionuclides include clinoptilolite and mordenite (zeolites), clay minerals, and iron and manganese oxides and hydroxides. Water compositions along flow paths beneath Yucca Mountain are controlled by dissolution reactions, silica and calcite precipitation, and ion-exchange reactions. Radionuclide concentrations along flow paths from a repository could be limited by (1) low waste-form dissolution rates, (2) low radionuclide solubility, and (3) radionuclide sorption onto geological media.

  10. Artificial neural/chemical networks

    Science.gov (United States)

    Caulfield, H. John

    2001-11-01

    What strikes the attention of a neural network designer is that the chemicals seem to work not so much on individual neural circuits as on neural cell assemblies. These are large blocks of neural networks that carry out high level tasks using their constituent networks as needed. It follows to us that we might seek ways of achieving that same sort of behavior in an artificial neural network. In what follows, we provide two examples of how that might be done in an artificial system.

  11. VKTA Rossendorf: Laboratory for Environmental and Radionuclide Analysis

    International Nuclear Information System (INIS)

    Koehler, M.; Knappik, R.; Fiola, K.

    2015-01-01

    The VKTA (Nuclear Engineering and Analytics Inc.) is charged by the Free State of Saxony with the decommissioning and waste management of the nuclear installations at the research site Dresden-Rossendorf. This task includes the safe management and disposal of fissile material and radioactive wastes. The acquired expertise and our solution-oriented way of working are the basis for a varied range of services especially the environmental and radionuclide analyzes. The Laboratory for Environmental and Radionuclide Analysis is accredited according to DIN EN ISO/IEC 17025 and provides a sound range of analytical and metrological services including their coordination and management. The personnel and the rooms, measuring and technical equipment are particularly designed for our special field, the measuring of radioactivity. We are focussed on measuring artificial and natural radionuclides in a wide range of activity and in different sample matrices (e.g., urine, faeces, metals, soil, concrete, food, liquids). With the flexible accreditation of the radionuclide analytics the Laboratory is able to react shortly to changing requirements in decommissioning, environmental monitoring and radiation protection. Essential chemical and radiochemical methods are e.g.: · Alpha particle spectrometry, · Liquid scintillation counting, · gamma ray spectrometry, including Ultra-Low-Level, · High-resolution ICP-MS, · Chromatographic methods such as ion chromatography, gas chromatography, HPLC, · Electrochemical measuring methods such as potentiometry, voltammetry. The Laboratory offers analytical services to the research site Dresden-Rossendorf and national and international customers adapting its analytical procedures to the special needs of customers. The presentation demonstrates on the basis of examples the work of Laboratory within the scope of decommissioning of nuclear facilities, especially at a research site, from radiological preliminary investigation to declaration of

  12. The impacts of radionuclide releases into the marine environment

    International Nuclear Information System (INIS)

    1981-01-01

    The impact of radiation on the marine environment has been of interest to the international community since the advent of nuclear fission. This interest continues with the increasing industrial use of nuclear power and the associated need for the disposal of nuclear waste. Continued dumping of low-level waste into the sea and direct discharge of liquid effluents into coastal waters, as well as potential radionuclide additions to the deep ocean from other sources, dictates that the possible long-term effects on the seas must be closely watched. By means of field studies in contaminated environments, our knowledge of long-lived radionuclides, especially the transuranium elements, is increasing. We are far from the goal, however, of being able to predict the behaviour of these elements in the marine environment, particularly in the deep sea. We know even less about other long-lived radionuclides such as technetium, whose inventory may be as high as 170 000 kg by the year 2000 according to some projections. Clearly, attempts to unravel the behaviour and fate of these long-lived radionuclides introduced into the sea will present a challenge to the environmental scientist during the next decade. In addition, the new philosophy of the International Commission on Radiological Protection (ICRP) as set out in Publication No.26, emphasizes justification and optimization both in the release of radioactive effluents into the sea and in the sea-dumping of radioactive solid wastes. To satisfy the demands of this new philosophy requires a broader range of environmental information than has previously been available. The papers assembled for this symposium represent an authoritative account of the subject's global status in 1980. The object of the meeting was to review the origins, measurements, behaviour, fate and impacts of artificial radioactive additions to the marine environment

  13. Critical look at studies of radionuclide migration in fractured granite cores

    Energy Technology Data Exchange (ETDEWEB)

    Isherwood, D.; Failor, R.

    1983-05-01

    A series of laboratory experiments studying radionuclide migration were conducted on eleven fractured granite cores from the Climax Stock at the Nevada Test Site. Failor et al (1982) discuss the equipment used, the preparation of the core, the experimental procedure, the data reduction, and the experimental results. They give estimates of the average fracture apertures, retardation values of /sup 85/Sr, /sup 95m/Tc, and /sup 137/Cs relative to /sup 3/H, and the percentage of each radionuclide retained in the core after each run. To determine the effect of fracture fill material and solution composition on radionuclide migration, they studied both natural and artificial fractures using either natural Climax ground water or distilled water. The results are summarized below along with a discussion of the problems inherent in the experiments and suggestions to minimize these problems.

  14. Critical look at studies of radionuclide migration in fractured granite cores

    International Nuclear Information System (INIS)

    Isherwood, D.; Failor, R.

    1983-05-01

    A series of laboratory experiments studying radionuclide migration were conducted on eleven fractured granite cores from the Climax Stock at the Nevada Test Site. Failor et al (1982) discuss the equipment used, the preparation of the core, the experimental procedure, the data reduction, and the experimental results. They give estimates of the average fracture apertures, retardation values of 85 Sr, /sup 95m/Tc, and 137 Cs relative to 3 H, and the percentage of each radionuclide retained in the core after each run. To determine the effect of fracture fill material and solution composition on radionuclide migration, they studied both natural and artificial fractures using either natural Climax ground water or distilled water. The results are summarized below along with a discussion of the problems inherent in the experiments and suggestions to minimize these problems

  15. Activity concentrations and mean annual effective dose from gamma-emitting radionuclides in the Lebanese diet

    International Nuclear Information System (INIS)

    Nasreddine, L.; Hwalla, N.; El Samad, O.; Baydoun, R.; Hamze, M.; Parent-Massin, D.

    2008-01-01

    Since the primary factor contributing to the internal effective dose in the human organism is contaminated food, the control of radionuclides in food represents the most important means of protection. This study was conducted to determine the levels of the dietary exposure of the Lebanese population to gamma-emitting radioisotopes. The activity concentrations of gamma-emitting radioisotopes have been measured in food samples that represent the market basket of an adult urban population in Lebanon. The artificial radionuclide 137 Cs was measured above detection limits in only fish, meat and milk-based deserts. The most abundant natural radionuclide was 40 K (31-121 Bq kg -1 ), with the highest content in fish and meat samples. The annual mean effective dose contributed by 40 K in the reference typical diet was estimated equal to 186 μSv y -1 , a value reasonably consistent with findings reported by several other countries. (authors)

  16. Radionuclide synovectomy - essentials for rheumatologists.

    Science.gov (United States)

    Chojnowski, Marek M; Felis-Giemza, Anna; Kobylecka, Małgorzata

    2016-01-01

    Radionuclide synovectomy is a minimally invasive method of treating persistent joint inflammation. It involves intra-articular injection of radioactive colloids which induce necrosis and fibrosis of hypertrophic synovial membrane. The most common indication for radiosynovectomy is rheumatoid arthritis, although patients with seronegative spondyloarthropathies, unclassified arthritis, haemophilic arthropathy and other less common arthropathies can also benefit from this method. Radiosynovectomy is safe, well tolerated and efficacious. About 70-80% of patients respond well to the therapy. However, the therapeutic effects are considerably worse in patients with co-existent osteoarthritis and advanced joint degeneration. Despite its advantages, radionuclide synovectomy is not performed as often as it could be, so greater knowledge and understanding of this method are needed. The authors present the most important facts about radiosynovectomy that may help rheumatologists in their daily clinical practice.

  17. Radionuclide cinematography of the heart

    International Nuclear Information System (INIS)

    Adam, W.E.; Sigel, H.; Geffers, H.; Bitter, F.; Meyer, G.; Kampmann, H.; Stauch, M.

    1976-01-01

    Radionuclide cinematography is described as a procedure making use of radiation-level variations above the heart after equipartitioning of sup(99m)Tc-labelled human serum albumin in the blood pool. Regional ventricular and vestibular variations are phase-shifted. This procedure permits delineation of aneurysmas with interphasic course, cicatrization of the cardiac wall not producing any cyclical variation. The study included normal subjects and 16 patients with full course infarction. Characteristic disturbances of motility distribution were found in all cases of scarred or aneurysmic alterations in the frontal and side walls of the left ventricle. The procedure was unable to detect two small infarction scars on the rear wall. The possibility of using radionuclide cinematography to prove coronary insufficiency as well as a comparison with other methods are discussed

  18. Choice of radionuclides for radioimmunotherapy

    International Nuclear Information System (INIS)

    DeNardo, S.J.; Jungerman, J.A.; DeNardo, G.L.; Lagunas-Solar, M.C.; Cole, W.C.; Meares, C.F.

    1985-01-01

    Innumerable questions need to be answered and obstacles overcome before radioimmunotherapy can be generally successful in cancer patients. Major developments have greatly enhanced the likelihood of success. The important development of appropriate radionuclides and radiochemistry for this therapy must be intimately linked with the biological and biochemical realities. All aspects must be considered, such as the specific nature of the antigenic target, the pharmacokinetics of the antibody fragment carrier, the capability of in vivo quantitation of tumor uptake and turnover time, as well as total body kinetics. With this knowledge, then, practical radiochemistry methods can be integrated with the suitable radionuclide choices, and production methods can be developed which will deliver effective and dependable products for patient therapy

  19. Radionuclide imaging of musculoskeletal infection

    Energy Technology Data Exchange (ETDEWEB)

    Palestr, Christopher J. [Albert Einstein College of Medicine, Bronx, NY (United States); North Shore Long Island Jewish Health System, Manhasset and New Hyde Park, NY (United States). Div. of Nuclear Medicine and Molecular Imaging; E-mail: palestro@lij.edu; Love, Charito [North Shore Long Island Jewish Health System, Manhasset and New Hyde Park, NY (United States). Div. of Nuclear Medicine and Molecular Imaging

    2007-09-15

    Radionuclide imaging studies are routinely used to evaluate patients suspected of having musculoskeletal infection. Three-phase bone imaging is readily available, relatively inexpensive, and very accurate in the setting of otherwise normal bone. Labeled leukocyte imaging should be used in cases of 'complicating osteomyelitis' such as prosthetic joint infection. This test also is useful in clinically unsuspected diabetic pedal osteomyelitis as well as in the neuropathic joint. It is often necessary, however, to perform complementary bone marrow imaging, to maximize the accuracy of labeled leukocyte imaging. In contrast to other regions in the skeleton, labeled leukocyte imaging is not useful for diagnosing spinal osteomyelitis. At the moment, gallium is the preferred radionuclide procedure for this condition and is a useful adjunct to magnetic resonance imaging. FDG-PET likely will play an important role in the evaluation of musculoskeletal infection, especially spinal osteomyelitis, and may replace gallium imaging for this purpose. (author)

  20. Radionuclide imaging of musculoskeletal infection

    International Nuclear Information System (INIS)

    Palestr, Christopher J.; North Shore Long Island Jewish Health System, Manhasset and New Hyde Park, NY; Love, Charito

    2007-01-01

    Radionuclide imaging studies are routinely used to evaluate patients suspected of having musculoskeletal infection. Three-phase bone imaging is readily available, relatively inexpensive, and very accurate in the setting of otherwise normal bone. Labeled leukocyte imaging should be used in cases of 'complicating osteomyelitis' such as prosthetic joint infection. This test also is useful in clinically unsuspected diabetic pedal osteomyelitis as well as in the neuropathic joint. It is often necessary, however, to perform complementary bone marrow imaging, to maximize the accuracy of labeled leukocyte imaging. In contrast to other regions in the skeleton, labeled leukocyte imaging is not useful for diagnosing spinal osteomyelitis. At the moment, gallium is the preferred radionuclide procedure for this condition and is a useful adjunct to magnetic resonance imaging. FDG-PET likely will play an important role in the evaluation of musculoskeletal infection, especially spinal osteomyelitis, and may replace gallium imaging for this purpose. (author)

  1. Radionuclide transfer in terrestrial animals

    International Nuclear Information System (INIS)

    DiGregorio, D.; Kitchings, T.; Van Voris, P.

    1978-01-01

    The analysis of dispersion of radionuclides in terrestrial food chains, generally, is a series of equations identifying the fractional input and outflow rates from trophic level to trophic level. Data that are prerequisite inputs for these food chain transport models include: (1) identification of specific transport pathway, (2) assimilation at each pathway link, and (3) the turnover rate or retention function by successive receptor species in the appropriate food chain. In this report, assimilation coefficients, biological half-lives, and excretion rates for a wide variety of vertebrate and invertebrate species and radionuclides have been compiled from an extensive search of the available literature. Using the information accumulated from the literature, correlations of nuclide metabolism and body weight are also discussed. (author)

  2. Terrestrial pathways of radionuclide particulates

    International Nuclear Information System (INIS)

    Boone, F.W.; Ng, Y.C.

    1981-01-01

    Formulations are developed for computing potential human intake of 13 radionuclides via the terrestrial food chains. The formulations are an extension of the NRC methodology. Specific regional crop and livestock transfer and fractional distribution data from the southern part of the U.S.A. are provided and used in the computation of comparative values with those computed by means of USNRC Regulatory Guide 1.109 formulations. In the development of the model, emphasis was also placed on identifying the various time-delay compartments of the food chains and accounting for all of the activity initially deposited. For all radionuclides considered, except 137 Cs, the new formulations predict lower potential intakes from the total of all food chains combined than do the comparable Regulatory Guide formulations by as much as a factor of 40. For 137 Cs the new formulations predict 10% higher potential intakes. (author)

  3. Radionuclide evaluation of renal transplants

    International Nuclear Information System (INIS)

    Yang Hong; Zhao Deshan

    2000-01-01

    Radionuclide renal imaging and plasma clearance methods can quickly quantitate renal blood flow and function in renal transplants. They can diagnose acute tubular necrosis and rejection, renal scar, surgical complications such as urine leaks, obstruction and renal artery stenosis after renal transplants. At the same time they can assess the therapy effect of renal transplant complications and can also predict renal transplant survival from early post-operative function studies

  4. Radionuclide dispersion in the atmosphere

    International Nuclear Information System (INIS)

    Moura Neto, C. de; Amorim, E.S. do; Panetta, J.

    1979-05-01

    The instantaneous liberation of radionuclides in the atmosphere is studied in three dimensions, according to the formalism of the diffusion theory. The analytical solution, expose to gravitational and an atmospherical effects, is combined with the discretization of space and time in the calculation of levels of exposure. A typical inventory (for a PWR) was considered in the calculation of immersion doses, and the results permitted a comparative analysis among the different existing models. (Author) [pt

  5. Metabolism of radionuclides in domestic animals

    International Nuclear Information System (INIS)

    Wirth, E.; Leising, C.

    1986-01-01

    The reactor accident at Chernobyl has shown that shortly after the contamination of the environment radionuclides can be found in animal products. The main contamination pathways of domestic animas are: uptake of radionuclides by foodstuffs; uptake of radionuclides by contaminated drinking water; uptake of radionuclides by inhalation; uptake of radionuclides through skin; uptake of radionuclides by ingestion of soil particles. Generally the uptake of radionuclides by food is the dominant exposure pathway. In rare cases the inhalation of radionuclides or the uptake by drinking water may be of importance. The metabolism of incorporated radionuclides is comparable to the respective metabolism of essential mass or trace elements or heavy metals. Radioisotopes of essential elements are for instance iron 55, manganese 54, cobalt 58 and cobalt 60. Other elements are typical antagonists to essential elements, e.g. strontium 90 is an antagonist to calcium or cesium 137 to potassium. Lead 210 and plutonium 239 behave similarly as heavy metals. Generally the knowledge of the metabolism of trace and mass elements, of antagonistic and synergistic elements and heavy metals can be applied to these radionuclides

  6. Tracking the complete revolution of surface westerlies over Northern Hemisphere using radionuclides emitted from Fukushima

    International Nuclear Information System (INIS)

    Hernández-Ceballos, M.A.; Hong, G.H.; Lozano, R.L.; Kim, Y.I.; Lee, H.M.; Kim, S.H.; Yeh, S.-W.; Bolívar, J.P.; Baskaran, M.

    2012-01-01

    Massive amounts of anthropogenic radionuclides were released from the nuclear reactors located in Fukushima (northeastern Japan) between 12 and 16 March 2011 following the earthquake and tsunami. Ground level air radioactivity was monitored around the globe immediately after the Fukushima accident. This global effort provided a unique opportunity to trace the surface air mass movement at different sites in the Northern Hemisphere. Based on surface air radioactivity measurements around the globe and the air mass backward trajectory analysis of the Fukushima radioactive plume at various places in the Northern Hemisphere by employing the Hybrid Single-Particle Lagrangian Integrated Trajectory model, we show for the first time, that the uninterrupted complete revolution of the mid-latitude Surface Westerlies took place in less than 21 days, with an average zonal velocity of > 60 km/h. The position and circulation time scale of Surface Westerlies are of wide interest to a large number of global researchers including meteorologists, atmospheric researchers and global climate modellers. -- Highlights: ► Evidence of the South Korea contamination with released radiocesium from Fukushima. ► Field samples and air mass analysis were utilized to elucidate the transport of those radionuclides. ► Characterization of the air mass movements at different sites at the Earth's surface. ► Verification of the uninterrupted complete revolution of the artificial radionuclides released in Fukushima. ► Quantification of the velocity of the artificial radionuclides released in Fukushima.

  7. Targeted Radionuclide Therapy of Human Tumors

    Directory of Open Access Journals (Sweden)

    Sergey V. Gudkov

    2015-12-01

    Full Text Available Targeted radionuclide therapy is one of the most intensively developing directions of nuclear medicine. Unlike conventional external beam therapy, the targeted radionuclide therapy causes less collateral damage to normal tissues and allows targeted drug delivery to a clinically diagnosed neoplastic malformations, as well as metastasized cells and cellular clusters, thus providing systemic therapy of cancer. The methods of targeted radionuclide therapy are based on the use of molecular carriers of radionuclides with high affinity to antigens on the surface of tumor cells. The potential of targeted radionuclide therapy has markedly grown nowadays due to the expanded knowledge base in cancer biology, bioengineering, and radiochemistry. In this review, progress in the radionuclide therapy of hematological malignancies and approaches for treatment of solid tumors is addressed.

  8. Microbial Transformations of Actinides and Other Radionuclides

    Energy Technology Data Exchange (ETDEWEB)

    Francis,A.J.; Dodge, C. J.

    2009-01-07

    Microorganisms can affect the stability and mobility of the actinides and other radionuclides released from nuclear fuel cycle and from nuclear fuel reprocessing plants. Under appropriate conditions, microorganisms can alter the chemical speciation, solubility and sorption properties and thus could increase or decrease the concentrations of radionuclides in solution in the environment and the bioavailability. Dissolution or immobilization of radionuclides is brought about by direct enzymatic action or indirect non-enzymatic action of microorganisms. Although the physical, chemical, and geochemical processes affecting dissolution, precipitation, and mobilization of radionuclides have been extensively investigated, we have only limited information on the effects of microbial processes and biochemical mechanisms which affect the stability and mobility of radionuclides. The mechanisms of microbial transformations of the major and minor actinides U, Pu, Cm, Am, Np, the fission products and other radionuclides such as Ra, Tc, I, Cs, Sr, under aerobic and anaerobic conditions in the presence of electron donors and acceptors are reviewed.

  9. Targeted Radionuclide Therapy of Human Tumors

    OpenAIRE

    Gudkov, Sergey V.; Shilyagina, Natalya Yu.; Vodeneev, Vladimir A.; Zvyagin, Andrei V.

    2015-01-01

    Targeted radionuclide therapy is one of the most intensively developing directions of nuclear medicine. Unlike conventional external beam therapy, the targeted radionuclide therapy causes less collateral damage to normal tissues and allows targeted drug delivery to a clinically diagnosed neoplastic malformations, as well as metastasized cells and cellular clusters, thus providing systemic therapy of cancer. The methods of targeted radionuclide therapy are based on the use of molecular carrier...

  10. Production of radionuclides in nuclear reactor

    International Nuclear Information System (INIS)

    Vucina, J.; Vuksanovic, Lj.; Dobrijevic, R.

    1998-01-01

    Given is a short review on the production of radionuclides which was performed in the Vinca Institute of Nuclear Sciences by using the nuclear reactor RA. Regarding the considerations of the possible re-starting of this reactor its use for the production of medical radionuclides should be taken into account. Listed are some of the important medical radionuclides routinely produced in nuclear reactors in the world and discussed the conditions for their obtaining in the reactor RA. (author)

  11. MIRD radionuclide data and decay schemes

    CERN Document Server

    Eckerman, Keith F

    2007-01-01

    For all physicians, scientists, and physicists working in the nuclear medicine field, the MIRD: Radionuclide Data and Decay Schemes updated edition is an essential sourcebook for radiation dosimetry and understanding the properties of radionuclides. Includes CD Table of Contents Decay schemes listed by atomic number Radioactive decay processes Serial decay schemes Decay schemes and decay tables This essential reference for nuclear medicine physicians, scientists and physicists also includes a CD with tabulations of the radionuclide data necessary for dosimetry calculations.

  12. Methods in environmental sampling for radionuclides

    International Nuclear Information System (INIS)

    Ragaini, R.C.

    1976-01-01

    This paper reviews methods of environmental sampling for radionuclides around operational and preoperational nuclear power plants. We examine in detail the implications of the established radiation standards and their effect on sampling procedures. Transport mechanisms of radionuclides in liquid effluent, and the deposition of airborne radionuclides onto soil and vegetation are discussed. We evaluate water- and soil-sampling procedures. The Lawrence Livermore Laboratory program of terrestrial gamma-ray surveys at preoperational nuclear power plants is described

  13. Environmental behaviour of radionuclides and transfer to man

    International Nuclear Information System (INIS)

    Smith, H.

    1982-01-01

    The environmental behaviour of the radionuclides making the major contribution to man's irradiation through diet is described. The following stages are emphasized: transfer of radionuclides to plants; transfer of radionuclides to animals; metabolism of inhaled or ingested radionuclides in animals providing food for man; transfer of radionuclides through the aquatic environment; application of food chain models. (43 references)

  14. Natural radionuclides in effluents release by a deactivated uranium mine

    International Nuclear Information System (INIS)

    Pereira, Wagner S.; Kelecom, Alphonse; Silva, Ademir X.; Lopes, José M.; Pinto, Carlos E.C.; Py Júnior, Delcy A.; Antunes, Marcos M.; Indústrias Nucleares do Brasil; Universidade Federal Fluminense; Coordenacao de Pos-Graduacao e Pesquisa de Engenharia

    2017-01-01

    The Ore Treatment Unit (OTU) is a mine and deactivated uranium plant in the city of Caldas, Minas Gerais, Brazil. This facility possesses three points of release of liquid effluents containing radionuclides: point 014, 025 and 076. At these points, the values of activity concentrations (AC) of the radionuclides U nat , 226 Ra, 210 Pb, 232 Th and 228 Ra were analyzed in 2012. The evaluation of point 014 by univariate statistics pointed four groups. [U nat > 228 Ra > ( 226 Ra = 210 Pb) > 232 Th]. The multivariate statistics separated the radionuclides into two groups: [(U nat and 232 Th) and ( 226 Ra, 228 Ra and 210 Pb)]. At point 025, the univariate statistics described three groups: [Un at > ( 228 Ra = 210 Pb) > ( 226 Ra = 232 Th)] and the multivariate analysis also described three but different groups: [(U nat and 228 Ra), ( 226 Ra and 210 Pb) and 232 Th]. In turn, point 076 showed another behavior. The univariate analysis showed only two groups: [(U nat ) > ( 226 Ra, 228 Ra, 210 Pb, 232 Th)]. Differently, the multivariate statistics defined three groups: [(U nat and 232 Th), ( 226 Ra and 228 Ra) and 210 Pb].Thus, statistical analysis showed that each point has releases of effluents with different characteristics. Both the behaviors of releases, based on multivariate statistics, and of the AC magnitudes, based on the univariate statistics, are different between the points. The only common features were the greater magnitude of uranium and the smaller magnitude of thorium. (author)

  15. Therapy for incorporated radionuclides: scope and need

    International Nuclear Information System (INIS)

    Smith, V.H.

    1981-03-01

    In the United States the recent termination of funding for research on therapy for incorporated radionuclides has virtually halted progress on improved or new agents and procedures for removing radioactivity from the body. Research was eliminated, but is still needed on new removal agents, improved delivery system, in vitro test systems, and the toxicology of treatments. For many radionuclides, no adequate therapy exists. The relationship between radionuclide removal and reduction in cancer risk is still unanswered. Without proper research support, needed improvements in the treatment for incorporated radionuclides in the US are uncertain

  16. Radionuclide accumulation peculiarities demonstrated by vegetable varieties

    International Nuclear Information System (INIS)

    Kruk, A.V.; Goncharenko, G.G.; Kilchevsky, A.V.

    2004-01-01

    This study focused on ecological and genetic aspects of radionuclide accumulation demonstrated by a number of vegetable varieties. The researches resulted in determining the cabbage varieties which were characterised by the minimal level of radionuclide accumulation. It was shown that the above varieties manifested the relation between radionuclide accumulation and morphobiological characteristics such as vegetation period duration and yield criteria. The study specified the genotypes with high ecological stability as regards to radionuclide accumulation: 'Beloruskaya 85' cabbage and 'Dokhodny' tomato showed the best response to Cs 137, while 'Beloruskaya 85', 'Rusinovka', 'Amager 611' cabbage varieties and 'Sprint' tomato showed the minimal level of Sr 90 accumulation. (authors)

  17. Radionuclide migration in plants of forest phytocenoses

    International Nuclear Information System (INIS)

    Kabashnikova, G.I.; Bolotskikh, T.N.

    1992-01-01

    Five-year observations are generalized on a dynamic of a radionuclide accumulation and a radionuclide migration in lives of 8 species of young tress (an oak, an aspen, a birch, an alder, a fir, a pine, a maple) and 16 species of bushes (raspberry, amountain ash, a willow and other). The former have the more considerable radionuclide content, then the latter. The change of plant radioactivity is dependent upon the radionuclide soil contamination, local conditions and species belonging of the plants. The data are needed for pharmacological industry, using the plants for medicines. 19 refs

  18. Study of the thermo-mechanical behavior of medium carbon microalloyed steel during hot forming process using an artificial neural network; Estudio del comportamiento termo-mecanico de un acero microaleado de medio carbono durante un proceso de conformado en caliente usando una red neuronal artificial

    Energy Technology Data Exchange (ETDEWEB)

    Alcelay, I.; Pena, E.; Al Omar, A.

    2016-10-01

    The thermo-mechanical behavior of medium carbon microalloyed steel has been analyzed by an Artificial Neural Network (ANN). The flow curves for training the ANN have been obtained from the hot compression tests, carried out over a temperature range varying from 900 to 1150 degree centigrade and at different true strain rates ranging from 10{sup -}4 to 10 s{sup -}1. It has been found that the ANN model developed in this study is capable to predict accurately and efficiently the flow behavior of the studied steel and there is a good agreement between the experimental results and the ANN results. To analyze the formability of the studied steel, processing maps have been constructed on the basis of the Dynamic Materials Model (DMM), using the ANN values of the flow stress. The study of maps reveals the different domains of the flow behavior of the studied steel and shows the great similarity between the experimental results and the theoretical results, so the use of the ANN can constitute an interesting alternative for design and study of hot forming processes. (Author)

  19. An Artificial Muscle Ring Oscillator

    OpenAIRE

    O’Brien, Benjamin Marc; Anderson, Iain Alexander

    2012-01-01

    Dielectric elastomer artificialmuscles have great potential for the creation of novel pumps, motors, and circuitry. Control of these devices requires an oscillator, either as a driver or clock circuit, which is typically provided as part of bulky, rigid, and costly external electronics. Oscillator circuits based on piezo-resistive dielectric elastomer switch technology provide a way to embed oscillatory behavior into artificial muscle devices. Previous oscillator circuits were not digital, ab...

  20. Sombra artificial e método de fornecimento de concentrado no comportamento e desempenho de bezerros desmamados =Artificial shade and method of concentrate supply in behavior and in performance of calves.

    Directory of Open Access Journals (Sweden)

    Geraldo Tadeus dos Santos

    2011-10-01

    Full Text Available Foram avaliados o comportamento, as variáveis fisiológicas e o desempenho de bezerros Holandês e mestiços desmamados em diferentes telas de polipropileno e horas de fornecimento de concentrado. Utilizaram-se 24 bezerros, nove da raça Holandesa (H e 15 mestiços de Holandês (MH, em piquetes parcialmente cobertos com tela de polipropileno com malha de 70 (S70 e 40% (S40 de sombra, recebendo concentrado em três horários: manhã (M, tarde (T e dias alternados (DA. Os comportamentos comendo e ruminando deitado foram, respectivamente, mais frequentes no ambiente S70 (34,29 e 11,40% do que no ambiente S40 (30,18 e 6,76%, indicando maior conforto térmico. Os comportamentos ruminando em pé e em pé foram, respectivamente, mais frequentes no ambiente S40 (6,42 e 40,25% do que no ambiente S70 (5,24 e 31,18%. A temperatura da superfície do pelame apresentou maior valor no ambiente S40 para os animais H (33,87ºC e MH (33,69ºC, principalmente nas horas mais quentes do dia, quando a radiação solar era maior. A frequência respiratória foi maior para os animais H tanto no ambiente S40 (55,66 mov. min.-1 quanto no ambiente S70 (60,98 mov. min.-1. O ganho de peso médio diário não variou conforme o fornecimento de ração, de sombra e entre grupos genéticos.It was evaluated the behavior, the physiological variables and the performance of Holstein calves and crossbred calves weaned using different shade screens and hours of concentrate supplying. There were used nine Holstein calves (H and 15 crossbred Holstein calves (MH, housed on partially covered paddocks with a polypropylene screen (shade with a loop of 70% of shadow (S70 and 40% (S40 receiving concentrate at three times: morning (M, afternoon (A and alternate days (AD. The behaviors eating and ruminating lying were, respectively, more frequent on the environment S70 (34.29 and 11.40% than on the environment S40 (30.18 and 6.76%, showing greater termical comfort for calves. The behaviors

  1. Radionuclide Release after LBLOCA with Loss of Class IV Power Accident in CANDU-6 Plant

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Hoon [KHNP Central Research Institute, Daejeon (Korea, Republic of)

    2011-10-15

    A large break in a pipe train of a primary heat transport system discharges coolant, which has high energy and large mass, into the containment building. Reactor shutdown and emergency core cooling water will limit the fuel cladding failure, but cannot prevent it entirely. The containment building is the last barrier of radionuclide release to the environment. Containment isolation and pressure suppression by dousing and local air cooler reduce the amount of radionuclide release to the environment. The objective of containment behavior analysis for large break loss of coolant with loss of class IV power accident is to assess the amount of radionuclide release to the ambient atmosphere. Radionuclide release rates in this event, with all safety system available, that is, the containment building is intact, as well as with containment system impairment, are analyzed with GOTHIC and SMART code

  2. Radionuclide dating (21Pb, 137Cs, 241Am) of recent lake sediments in a highly active geodynamic setting (Lakes Puyehue and Icalma-Chilean Lake District)

    International Nuclear Information System (INIS)

    Arnaud, F.; Magand, O.; Chapron, E.; Bertrand, S.; Boes, X.; Charlet, F.; Melieres, M.-A.

    2006-01-01

    This study presents an attempt to use radionuclide profiles to date four short sediment cores taken from two Chilean lakes located in a highly active geodynamic setting. In such settings, sediment series commonly contain earthquake-triggered reworked layers and/or volcanic ash layers. All of these layers affect the vertical distribution of radionuclides. The drawing up of accurate chronologies is made even more problematic by the low fallout rates of both natural ( 21 Pb) and artificial ( 137 Cs, 241 Am) radionuclides. However, radionuclide profiles can be 'corrected' by subtracting the influence of instantaneous deposits that have been identified from detailed sedimentological studies. Thus, radionuclides can be used to provide approximate dates for sediment. Independent confirmation of these dates can be provided by varve counting and/or the recognition of historical events. For Lake Puyehue, this approach has allowed particular sediment features to be related to the effects of the 1960 Chilean earthquake (Mw 9.5) on the lake basin and its catchment area. For Lake Icalma, there is a good agreement between radionuclide dates and the dates of the three tephra layers formed during large eruptions of the Llaima volcano in 1946, 1917 and 1883. For both lakes, artificial radionuclide fallout, which culminated in 1965, provides more robust chronological information than 21 Pb dating

  3. Development of AI (Artificial Intelligence)-based simulation system for man-machine system behavior in accidental situations of nuclear power plant

    International Nuclear Information System (INIS)

    Yoshida, Kazuo; Yokobayashi, Masao; Tanabe, Fumiya; Kawase, Katumi.

    1996-01-01

    A prototype version of a computer simulation system named JACOS (JAeri COgnitive Simulation system) has been developed at JAERI (Japan Atomic Energy Research Institute) to simulate the man-machine system behavior in which both the cognitive behavior of a human operator and the plant behavior affect each other. The objectives of this system development is to provide man-machine system analysts with detailed information on the cognitive process of an operator and the plant behavior affected by operator's actions in accidental situations of an NPP (nuclear power plant). The simulation system consists of an operator model and a plant model which are coupled dynamically. The operator model simulates an operator's cognitive behavior in accidental situations based on the decision ladder model of Rasmussen, and is implemented using the AI-techniques of the distributed cooperative inference method with the so-called blackboard architecture. Rule-based behavior is simulated using knowledge representation with If-Then type of rules. Knowledge-based behavior is simulated using knowledge representation with MFM (Multilevel Flow Modeling) and qualitative reasoning method. Cognitive characteristics of attentional narrowing, limitation of short-term memory, and knowledge recalling from long-term memory are also modeled. The plant model of a 3-loop PWR is also developed using a best estimate thermal-hydraulic analysis code RELAP5/MOD2. Some simulations of incidents were performed to verify the human model. It was found that AI-techniques used in the human model are suitable to simulate the operator's cognitive behavior in an NPP accident. The models of cognitive characteristics were investigated in the effects on simulated results of cognitive behaviors. (author)

  4. Radionuclide transfer to meadow vegetation

    International Nuclear Information System (INIS)

    Goncharova, N.; Matsko, N.; Zhebrakova, I.; Montik, T.

    1999-01-01

    In the paper results of radioecological monitoring of natural plant populations in the 30 km zone of the Chernobyl Nuclear Power Plant (Polesky State Radioecological Reserve) during the period from 1987 to 1998 are presented. The level of radiation background in experimental areas varied from 0.1 to 30 mR/h that correspond to the total soil activity of 300-24000 kBq/m 2 (for May 1997). Monitoring was carried out including the radionuclide migration in natural plant complexes and transfer of 137 Cs between some plant organs. Refs. 3 (author)

  5. Radionuclide cisternography after head injury

    International Nuclear Information System (INIS)

    Barnes, B.D.; Hoff, J.T.

    1976-01-01

    Thirty-seven patients with severe head injury underwent radionuclide cisternography to detect early and late effects of trauma on cerebrospinal fluid (CSF) circulation. Thirty-one patients had subdural hematomas or hygromas and six had cerebral contusions without extracerebral masses. Cisternographic results were abnormal in 23 patients with subdural masses and normal in five who had only cerebral contusions. Of eight patients undergoing serial studies, one had persistent partial obstruction, five had partial resolution of abnormalities, and the two with progressive obstruction had their conditions improved by shunting. Angiography suggested transtentorial herniation in 11 patients with cisternal block, six of whom had clinical signs of herniation on the same side

  6. Artificial Disc Replacement

    Science.gov (United States)

    ... Spondylolisthesis BLOG FIND A SPECIALIST Treatments Artificial Disc Replacement (ADR) Patient Education Committee Jamie Baisden The disc ... Disc An artificial disc (also called a disc replacement, disc prosthesis or spine arthroplasty device) is a ...

  7. Trends in Artificial Intelligence.

    Science.gov (United States)

    Hayes, Patrick

    1978-01-01

    Discusses the foundations of artificial intelligence as a science and the types of answers that may be given to the question, "What is intelligence?" The paradigms of artificial intelligence and general systems theory are compared. (Author/VT)

  8. Artificial Hydration and Nutrition

    Science.gov (United States)

    ... Crisis Situations Pets and Animals myhealthfinder Food and Nutrition Healthy Food Choices Weight Loss and Diet Plans ... Your Health Resources Healthcare Management Artificial Hydration and Nutrition Artificial Hydration and Nutrition Share Print Patients who ...

  9. Artificial life and Piaget.

    Science.gov (United States)

    Mueller, Ulrich; Grobman, K H.

    2003-04-01

    Artificial life provides important theoretical and methodological tools for the investigation of Piaget's developmental theory. This new method uses artificial neural networks to simulate living phenomena in a computer. A recent study by Parisi and Schlesinger suggests that artificial life might reinvigorate the Piagetian framework. We contrast artificial life with traditional cognitivist approaches, discuss the role of innateness in development, and examine the relation between physiological and psychological explanations of intelligent behaviour.

  10. Artificial Intelligence Implications for Information Retrieval.

    Science.gov (United States)

    1983-04-01

    data entry, and (4) active memory techniques. In the remainder of this section we will describe each of these areas briefly. Artificial Intelligence applications In... Intelligence applications to information retrieval fall into four broad categories: (1) human-database interfaces, (2) conceptual Indexing, (3) automatic...the fact that some of the most difficult of intelligent behavior (i.e. common sense) seems intuitively easy. z. =2atgarIa at Al AiA1AnA Artificial

  11. artificial neural network (ann)

    African Journals Online (AJOL)

    2004-08-18

    Aug 18, 2004 ... forecasting models and artificial intelligence techniques and have become one of the major research fields (Kher and Joshin, 2003). (a) Artificial Neural Network and Electrical Load. Prediction. Neural network analysis is an Artificial Intelligence. (AI) approach to mathematical modeling. Neural. Networks ...

  12. Stochastic approach for radionuclides quantification

    Science.gov (United States)

    Clement, A.; Saurel, N.; Perrin, G.

    2018-01-01

    Gamma spectrometry is a passive non-destructive assay used to quantify radionuclides present in more or less complex objects. Basic methods using empirical calibration with a standard in order to quantify the activity of nuclear materials by determining the calibration coefficient are useless on non-reproducible, complex and single nuclear objects such as waste packages. Package specifications as composition or geometry change from one package to another and involve a high variability of objects. Current quantification process uses numerical modelling of the measured scene with few available data such as geometry or composition. These data are density, material, screen, geometric shape, matrix composition, matrix and source distribution. Some of them are strongly dependent on package data knowledge and operator backgrounds. The French Commissariat à l'Energie Atomique (CEA) is developing a new methodology to quantify nuclear materials in waste packages and waste drums without operator adjustment and internal package configuration knowledge. This method suggests combining a global stochastic approach which uses, among others, surrogate models available to simulate the gamma attenuation behaviour, a Bayesian approach which considers conditional probability densities of problem inputs, and Markov Chains Monte Carlo algorithms (MCMC) which solve inverse problems, with gamma ray emission radionuclide spectrum, and outside dimensions of interest objects. The methodology is testing to quantify actinide activity in different kind of matrix, composition, and configuration of sources standard in terms of actinide masses, locations and distributions. Activity uncertainties are taken into account by this adjustment methodology.

  13. Infusion of radionuclides throughout pregnancy

    International Nuclear Information System (INIS)

    Mountford-Lister, P.G.; Lambert, B.E.; Milner, A.C.; Kang, X.Z.

    1992-01-01

    This work is part of a long-term study to examine the cancer incidence in the offspring of mice exposed to 239 Pu or 147 Pm throughout pregnancy. The need to model the human intake scenario and the possibility of a critical period during uterine development necessitates constant availability of radionuclides throughout pregnancy. Various methods (multiple daily injections, infusion by external cannula and infusion by indwelling osmotic pump) have been examined and osmotic infusion pumps chosen. These pumps result in a near-constant blood concentration for up to 21 days. Part of the study is the estimation of dose to the critical haemopoietic tissues of the pup from a knowledge of the radionuclide distribution and kinetics. At present the distribution has been followed from birth to 180 days. Activity in the suckling pups at 7 days old is around 1 percent of the infused activity, though most of this is accounted for by the contents of the stomach and gastrointestinal tract. The liver and femur account for around 0.025 percent and 0.012 percent respectively per pup. Activity increases in both liver and femur during lactation after which both concentration and activity fall with time. Long-term studies with the pups of dams exposed to a range of 239 Pu concentrations between 0-70 kBq/kg are underway. Correlation of average organ dose with tumour incidence will be determined at completion of the life-span study. (Author) 39 refs., 5 tabs., 6 figs

  14. Radionuclide transit in esophageal varices

    International Nuclear Information System (INIS)

    Yeh, S.H.; Wang, S.J.; Wu, L.C.; Liu, R.S.; Tsai, Y.T.; Chiang, T.T.

    1985-01-01

    This study assessed esophageal motility in patients with esophageal varices by radionuclide transit studies. Data were acquired in list mode after an oral dose of 0.5 mCi Tc-99m sulfur colloid in 10 ml of water in the supine position above a low-energy all-purpose collimator of a gamma camera. The condensed image (CI) superimposed with a centroid curve was also produced in each case. Twenty-five normal subjects (N) and 32 patients (pts) with esophageal varices by endoscopy (large varices in Grades IV and V in 8 and small varices in Grade III or less in 24) were studied. TMTT, RTT, RF, and RI were all significantly increased in pts as compared to N. Especially, the transit time for the middle third (6.7 +- 2.6 sec vs 3.5 +- 0.9 sec in N, rho < 0.005) had the optimal sensitivy and specificity of 88% each at the cutoff value of 4.2 sec as determined by ROC analysis. In summary, radionuclide transit disorders occur in the majority of pts with esopageal varices. The middle RTT and CI are both optimal in sensitivity and specificity for detecting the abnormalities

  15. Sedimentary Processes. Quantification Using Radionuclides

    International Nuclear Information System (INIS)

    Carroll, J.; Lerche, I.

    2003-01-01

    The advent of radionuclide methods in geochronology has revolutionized our understanding of modern sedimentary processes in aquatic systems. This book examines the principles of the method and its use as a quantitative tool in marine geology, with emphasis on the Pb-210 method. The assumptions and consequences of models and their behaviour are described providing the necessary background to assess the advantages and trade-offs involved when choosing a particular model for application. One of the purposes of this volume is to disentangle the influences of complicating factors, such as sediment flux variations, post-depositional diffusion of radionuclides, and bio-irrigation of sediments, to arrive at sediment ages and to properly assess the attendant data uncertainty. Environmental impacts of chemical, nuclear, or other waste material are of concern in a variety of areas around the world today. A number of relevant examples are included, demonstrating how dating models are useful for determining sources of contaminants and interpreting their influence on the environment. The book is set at a level so that an able student or professional should have no difficulty in following the procedures and methods developed. Each chapter includes case histories showing the strengths and weaknesses of a given procedure with respect to a data example. Included with this volume is the computer source code of a new generation of modelling tools based on inverse numerical analysis techniques. This first generation of the modelling tool is included, along with detailed instructions and examples for its use, in an appendix

  16. Radionuclide evaluation of tubal function

    Energy Technology Data Exchange (ETDEWEB)

    Stone, S.C.; McCalley, M.; Braunstein, P.; Egbert, R.

    1985-05-01

    The tubal capacity to transport radioactively labeled human albumin microspheres deposited in the vaginal fornix and cervical canal and to concentrate them on the ovarian surface was evaluated in a group of 34 patient-volunteers. One millicurie of /sup 99m/Tc was used to label human albumin microspheres of 20 ..mu.. in diameter, suspended in 1 ml of saline. The distribution of the radioactive material was imaged on a gamma camera at different intervals between 15 and 240 minutes. The radiation dose to the ovaries was estimated to be similar to that of a hysterosalpingogram. The results of the radionuclide evaluation were compared with the surgical findings at the time of laparoscopy or laparotomy performed for diagnostic or therapeutic reasons. The overall correlation was 87.1%. It would appear that as opposed to the traditional hysterosalpingogram, a radionuclide test may give a better understanding of the functional capacity of the tube and may also prove a useful method in the evaluation of the results of tubal microsurgical procedures.

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

    International Nuclear Information System (INIS)

    Ballestra, S.; Gastaud, J.; Lopez, J.J.; Parsi, P.; Vas, D.

    1993-08-01

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

  18. Migration of radionuclides in chosen parts of food chains

    International Nuclear Information System (INIS)

    Cipakova, A.

    2006-01-01

    Results of environmental contamination measurements are reported. 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 . The amount of artificial radionuclides in the individual compartments of food chains is at present at a very low level. Mushrooms are characterised by high ability to accumulate radiocaesium. From studied species of mushrooms the highest value was determined in sample of Sarcodon imbricatum and specific activity achieved 6.24 kBq · kg -1 d. w. (author)

  19. Intercomparison of radionuclide measurements on marine sediment sample IAEA-300

    International Nuclear Information System (INIS)

    Ballestra, S.; Gastaud, J.; Lopez, J.J.; Parsi, P.; Vas, D.

    1994-09-01

    The results of an intercomparison exercise on a sediment from Baltic Sea, IAEA-300, designed for the determination of artificial and natural radionuclides' levels, are reported. The data from 159 laboratories representing 51 countries have been evaluated. The following are the recommended values, with confidence intervals, 40 K, 60 Co, 125 Sb, 134 Cs, 137 Cs, 155 Eu, 210 Pb, 210 Po, 228 Ra, 234 U, 238 U, 239+240 Pu and 241 Am. Information values for 54 Mn, 90 Sr, 226 Ra, 228 Th, 230 Th, 232 Th, 235 U and 238 Pu are also reported. All values are given on the reference date of 1 January 1993 and expressed in Bq kg -1 dry weight. (author)

  20. Origin, behaviour and fate of radionuclides in continental waters

    International Nuclear Information System (INIS)

    Eyrolle-Boyer, Frederique

    2015-01-01

    In this report for Accreditation to Supervise Research (HDR), the author first proposes an overview of his research works to outline how they relate to each other, and gives a summary of his PhD and post-PhD research works. Then, he more particularly reports and comments his works related to the origin of radionuclides: natural and artificial origin, liquid releases from nuclear installations, persistence of atmospheric fall-outs due to surface nuclear tests and to the Chernobyl accident, atmospheric fall-outs in France due to the Fukushima accident. He comments results obtained by another researcher related to the tracing of radionuclide origin in the Rhone river, and reports activity level measurements performed within French waters (and more particularly in the Rhone river, and in irrigation canals). He proposes a focus of the behaviour and coefficients of solid/solution distribution in the case of the Rhone river and of Fukushima water streams. He briefly comments the radiological quality of drinking waters (exposure to radiations and regulation, case of the Rhone river and of neighbouring coastal rivers). He discusses the flow of radionuclides towards the sea environment and proposes some material assessments. Results of various researches performed by the author or made under his supervision are discussed. They relate to extreme events (impact of floods on contaminant transport), to storages and sedimentary archives, and to the use of tritium and carbon 14 to study long cycles. Research perspectives are then discussed on various issues: consequences of typhoons and roles of organic particles in the transport or transfer of radioactivity in the case of Fukushima rivers, estuarine reactions [fr

  1. Natural radionuclides in Syrian diet and their daily intake

    International Nuclear Information System (INIS)

    Al-Masri, M.S.; Mukallati, H.; Al-Hamwi, A.; Khalili, H.; Hassan, M.; Assaf, H.; Amin, Y.; Nashawati, A.

    2004-01-01

    More than one hundred different food stuffs (meat, vegetables cereals, seafood,..) have been collected during 1998, 1999 and 2000 and analyzed for radioactivity as part of the National Food Monitoring Program in Syria. Results have shown that most of the observed concentrations were within the range of the worldwide values with the exception of relatively high levels of 210 Po being observed in fish, vegetables, mushrooms, herbs and flowers. The daily intakes of the radionuclides studied have been evaluated. Relatively high values, in comparison with some countries, were found for 210 Po (1.9 Bq/day). This is due to high content of 210 Po in wheat (2.3 Bq/kg) consumed by Syrians, the daily consumption of wheat by Syrians is about 526 g. In addition, natural and artificial radionuclides in some manufactured food of Syrian infant and their intake rates have been determined. Seventeen manufactured food and eleven types of canned milk were collected from the local market and their radioactivity analyzed. 210 Po activity concentration varied between 0.38 and 2.89 Bq/kg dry wt. in canned milk while the highest concentration in infant food was found to be 1.69 Bq/kg dry wt. Other radionuclide concentrations were below the limit of detection of 3 Bq/kg dry wt. and 4 Bq/kg dry wt. for 22' 6Ra and 228 Ra, respectively, while uranium concentration varied between 2.2 and 10.5 μg/kg dry wt. in milk samples and 0.78-6.0 μg/kg dry wt. in other food samples. (author)

  2. Radionuclide Geomicrobiology of the Deep Biosphere

    DEFF Research Database (Denmark)

    Anderson, Craig; Johnsson, Anna; Moll, Henry

    2011-01-01

    This review summarizes research into interactions between microorganisms and radionuclides under conditions typical of a repository for high-level radioactive waste in deep hard rock environments at a depth of approximately 500 m. The cell-radionuclide interactions of strains of two bacterial spe...

  3. Modeling Radionuclide Decay Chain Migration Using HYDROGEOCHEM

    Science.gov (United States)

    Lin, T. C.; Tsai, C. H.; Lai, K. H.; Chen, J. S.

    2014-12-01

    Nuclear technology has been employed for energy production for several decades. Although people receive many benefits from nuclear energy, there are inevitably environmental pollutions as well as human health threats posed by the radioactive materials releases from nuclear waste disposed in geological repositories or accidental releases of radionuclides from nuclear facilities. Theoretical studies have been undertaken to understand the transport of radionuclides in subsurface environments because that the radionuclide transport in groundwater is one of the main pathway in exposure scenarios for the intake of radionuclides. The radionuclide transport in groundwater can be predicted using analytical solution as well as numerical models. In this study, we simulate the transport of the radionuclide decay chain using HYDROGEOCHEM. The simulated results are verified against the analytical solution available in the literature. Excellent agreements between the numerical simulation and the analytical are observed for a wide spectrum of concentration. HYDROGECHEM is a useful tool assessing the ecological and environmental impact of the accidental radionuclide releases such as the Fukushima nuclear disaster where multiple radionuclides leaked through the reactor, subsequently contaminating the local groundwater and ocean seawater in the vicinity of the nuclear plant.

  4. Value of radionuclide studies in cardiac transplantation

    International Nuclear Information System (INIS)

    Flotats, A.; Carrio, I.

    2006-01-01

    Effective noninvasive evaluation of acute and chronic allograft rejection remains an important challenge in patients with cardiac transplantation. Radionuclide studies have demonstrated utility because of their ease of use, giving relevant information about the pathophysiology of the transplanted heart, along with valuable diagnostic and prognostic indicators. This article focuses on reviewing the pathophysiological changes of the transplanted heart and implications for radionuclide studies. (author)

  5. Radiographic and radionuclide findings in Rhizopus osteomyelitis

    Energy Technology Data Exchange (ETDEWEB)

    Moore, P.H. Jr.; McKinney, R.G.; Mettler, F.A. Jr.

    1978-06-01

    A case of Rhizopus osteromyelitis is described. The radionuclide and radiographic findings differ from those of osteomyelitis secondary to common pathogens: low-level radionuclide activity is observed, while soft-tissue swelling, periosteal reaction, and loss of fascial margins are absent.

  6. Radionuclide content of local and imported cements used in Egypt

    International Nuclear Information System (INIS)

    Mahmoud, K R

    2007-01-01

    The activity concentrations of natural and artificial gamma-ray emitting radionuclides in local and imported cement have been investigated during the period from 2000 to 2003 using a 50% HPGe γ-spectroscopy system. The total numbers of local and imported samples were 29 and 8, respectively. The results showed a low activity concentration of 137 Cs in both the local and imported samples. The only exception was found in one imported Portland cement (2.8 ± 0.2 Bq kg -1 ) and one local blast furnace slag cement (1.9 ± 0.3 Bq kg -1 ). The average activity concentrations of 226 Ra, 232 Th and 40 K in local cement were 33 ± 17, 14 ± 2.4 and 45 ± 26 Bq kg -1 , respectively, whereas those in imported cement were 27 ± 7, 8 ± 7 and 134 ± 22 Bq kg -1 , respectively. The results showed that blast furnace slag cement contains the highest level of natural radioactivity, whereas white cement contains the lowest levels. The measured activity concentrations of the detected radionuclides were compared with other measurements carried out in Egypt and elsewhere. Radium-equivalent activities were also calculated to assess the radiation hazards arising from using such material in the construction of dwellings. Generally, the radium-equivalents of the analysed samples were smaller than the guideline limit of 370 Bq kg -1

  7. Sensors and Automated Analyzers for Radionuclides

    International Nuclear Information System (INIS)

    Grate, Jay W.; Egorov, Oleg B.

    2003-01-01

    The production of nuclear weapons materials has generated large quantities of nuclear waste and significant environmental contamination. We have developed new, rapid, automated methods for determination of radionuclides using sequential injection methodologies to automate extraction chromatographic separations, with on-line flow-through scintillation counting for real time detection. This work has progressed in two main areas: radionuclide sensors for water monitoring and automated radiochemical analyzers for monitoring nuclear waste processing operations. Radionuclide sensors have been developed that collect and concentrate radionuclides in preconcentrating minicolumns with dual functionality: chemical selectivity for radionuclide capture and scintillation for signal output. These sensors can detect pertechnetate to below regulatory levels and have been engineered into a prototype for field testing. A fully automated process monitor has been developed for total technetium in nuclear waste streams. This instrument performs sample acidification, speciation adjustment, separation and detection in fifteen minutes or less

  8. Speciation of radionuclides in the environment

    International Nuclear Information System (INIS)

    Gunten, H.R. von; Benes, P.

    1994-02-01

    Methods for the determination of the speciation of radionuclides in aerosols, in aquatic solutions, in sediments, soils and rocks are reviewed. At present, most of the results about speciation are deduced from model calculations, model experiments, and separation of species (forms) of radionuclides, e.g., by sequential extraction procedures. Methods of direct determination of speciation of radionuclides (e.g. by laser induced spectroscopy) are in general not yet sensitive enough for a measurement of the very low concentrations of radionuclides in the environment. The methodological part of this paper is followed by a review of the very abundant literature about speciation of important radionuclides in the environment, i.e. in the atmosphere, hydrosphere and lithosphere. The review does not include the biosphere. Literature up to spring 1993 is included (with a few more recent additions). (author)

  9. Behaviorism

    Science.gov (United States)

    Moore, J.

    2011-01-01

    Early forms of psychology assumed that mental life was the appropriate subject matter for psychology, and introspection was an appropriate method to engage that subject matter. In 1913, John B. Watson proposed an alternative: classical S-R behaviorism. According to Watson, behavior was a subject matter in its own right, to be studied by the…

  10. Behavior

    NARCIS (Netherlands)

    Bouwman, L.I.

    2014-01-01

    Health behaviors are people’s actions, some purposefully deployed to promote or protect health; some thoughtlessly undertaken without concern for their potential risk to health; some consciously, even defiantly, deployed regardless of consequences to health. Risk behaviors are specific forms of

  11. The impact of replacing sugar- by artificially-sweetened beverages on brain and behavioral responses to food viewing - An exploratory study.

    Science.gov (United States)

    Crézé, Camille; Notter-Bielser, Marie-Laure; Knebel, Jean-François; Campos, Vanessa; Tappy, Luc; Murray, Micah; Toepel, Ulrike

    2018-04-01

    Several studies indicate that the outcome of nutritional and lifestyle interventions can be linked to brain 'signatures' in terms of neural reactivity to food cues. However, 'dieting' is often considered in a rather broad sense, and no study so far investigated modulations in brain responses to food cues occurring over an intervention specifically aiming to reduce sugar intake. We studied neural activity and liking in response to visual food cues in 14 intensive consumers of sugar-sweetened beverages before and after a 3-month replacement period by artificially-sweetened equivalents. Each time, participants were presented with images of solid foods differing in fat content and taste quality while high-density electroencephalography was recorded. Contrary to our hypotheses, there was no significant weight loss over the intervention period and no changes were observed in food liking or in neural activity in regions subserving salience and reward attribution. However, neural activity in response to high-fat, sweet foods was significantly reduced from pre-to post-intervention in prefrontal regions often linked to impulse control. This decrease in activity was associated with weight loss failure, suggesting an impairment in individuals' ability to exert control and adjust their solid food intake over the intervention period. Our findings highlight the need to implement multidisciplinary approaches when aiming to help individuals lose body weight. Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. A Novel Framework for Characterizing Exposure-Related Behaviors Using Agent-Based Models Embedded with Needs-Based Artificial Intelligence (CSSSA2016)

    Science.gov (United States)

    Descriptions of where and how individuals spend their time are important for characterizing exposures to chemicals in consumer products and in indoor environments. Herein we create an agent-based model (ABM) that is able to simulate longitudinal patterns in behaviors. By basing o...

  13. The thorium phosphate diphosphate as matrix for radioactive waste conditioning: radionuclide immobilization and behavior under irradiation; Le phosphate diphosphate de thorium, matrice pour le conditionnement des dechets radioactifs: immobilisation de radionucleides, comportement sous irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Pichot, Erwan [Inst. de Physique Nucleaire, Paris-11 Univ., 91 - Orsay (France)

    1999-04-13

    The aim of this work was to perform successively the decontamination of liquid solutions and the final immobilization of radionuclide storage using the same matrix. For this, thorium phosphate-diphosphate (TPD) of the formula Th{sub 4}P{sub 6}O{sub 23}, is proposed as a very resistant to water corrosion matrix. A new compound, thorium phosphate hydrogeno-phosphate (TPHP) of the formula Th{sub 2}(PO{sub 4}){sub 2}(HPO{sub 4}), nH{sub 2}O with n=3-7 was synthesized and characterized. Heated at 1100 deg.C it is transformed into the TDP. Ion exchange properties of TPHP were investigated. The exchange yields of imponderable caesium, strontium and americium ion onto TPHP (NaNO{sub 3} 0.1 M media at pH=6) are equal to 60% for the first one and 100% for the two others. The results interpreted in terms of ion-exchange led to determine selectivity coefficient values for each cation and suggested that only hydrated ions are exchanged. While the TPD is proposed for the high level nuclear waste storage, the irradiation effects, particularly structural modifications were studied using both {gamma} irradiation and charged particle irradiation. ESR and TL methods were carried out in order to identify radicals created during gamma radiation exposure. Correlation between ESR and TL experiments performed at room temperature clearly show three of PO{sub 3}{sup 2-} species and one POO{center_dot} species of free radicals. We have shown that Au-ion irradiation in the range of MeV energy involved TPD structure and chemical modifications. Important sputtering was interpreted in terms of local thermal chemical decomposition. We have shown, at room temperature, that the amorphization dose for heavy ion irradiation is between 0.1 to 0.4 dpa. (author) 146 refs., 46 figs., 21 tabs.

  14. Transverse section radionuclide scanning system

    International Nuclear Information System (INIS)

    Kuhl, D.E.; Edwards, R.Q.

    1976-01-01

    This invention provides a transverse section radionuclide scanning system for high-sensitivity quantification of brain radioactivity in cross-section picture format in order to permit accurate assessment of regional brain function localized in three dimensions. High sensitivity crucially depends on overcoming the heretofore known raster type scanning, which requires back and forth detector movement involving dead-time or partial enclosure of the scan field. Accordingly, this invention provides a detector array having no back and forth movement by interlaced detectors that enclose the scan field and rotate as an integral unit around one axis of rotation in a slip ring that continuously transmits the detector data by means of laser emitting diodes, with the advantages that increased amounts of data can be continuously collected, processed and displayed with increased sensitivity according to a suitable computer program. 5 claims, 11 figures

  15. Expert system based radionuclide identification

    International Nuclear Information System (INIS)

    Aarnio, P.A.; Ala-Heikkil, J.J.; Hakulinen, T.T.; Nikkinen, M.T.

    1998-01-01

    An expert system coupled with the gamma spectrum analysis system SAMPO has been developed for automating the qualitative identification of radionuclides as well as for determining the quantitative parameters of the spectrum components. The program is written in C-language and runs in various environments ranging from PCs to UNIX workstations. The expert system utilizes a complete gamma library with over 2600 nuclides and 80,000 lines, and a rule base of about fifty criteria including energies, relative peak intensities, genesis modes, half lives, parent-daughter relationships, etc. The rule base is furthermore extensible by the user. This is not an original contribution but a somewhat updated version of papers and reports previously published elsewhere. (author)

  16. Radionuclide diagnosis of allograft rejection

    International Nuclear Information System (INIS)

    George, E.A.

    1982-01-01

    Interaction with one or more anatomical and physiopathological characteristics of the rejecting renal allograft is suggested by those radioagents utilized specifically for the diagnosis of allograft rejection. Rejection, the most common cause of declining allograft function, is frequently mimicked clinically or masked by other immediate or long term post transplant complications. Understanding of the anatomical pathological features and kinetics of rejection and their modification by immunosuppressive maintenance and therapy are important for the proper clinical utilization of these radioagents. Furthermore, in selecting these radionuclides, one has to consider the comparative availability, preparatory and procedural simplicity, acquisition and display techniques and the possibility of timely report. The clinical utilities of radiofibrinogen, /sup 99m/Tc sulfur colloid and 67 Ga in the diagnosis of allograft rejection have been evaluated to a variable extent in the past. The potential usefulness of the recently developed preparations of 111 In labeled autologous leukocytes and platelets are presently under investigation

  17. Radionuclides in surface and groundwater

    Science.gov (United States)

    Campbell, Kate M.

    2009-01-01

    Unique among all the contaminants that adversely affect surface and water quality, radioactive compounds pose a double threat from both toxicity and damaging radiation. The extreme energy potential of many of these materials makes them both useful and toxic. The unique properties of radioactive materials make them invaluable for medical, weapons, and energy applications. However, mining, production, use, and disposal of these compounds provide potential pathways for their release into the environment, posing a risk to both humans and wildlife. This chapter discusses the sources, uses, and regulation of radioactive compounds in the United States, biogeochemical processes that control mobility in the environment, examples of radionuclide contamination, and current work related to contaminated site remediation.

  18. Radionuclide interactions with marine sediments

    International Nuclear Information System (INIS)

    Higgo, J.J.W.

    1987-09-01

    A critical review of the literature on the subject of the interactions of radionuclides with marine sediments has been carried out. On the basis of the information available, an attempt has been made to give ranges and 'best estimates' for the distribution ratios between seawater and sediments. These estimates have been based on an understanding of the sediment seawater system and the porewater chemistry and mineralogy. Field measurements, laboratory measurements and estimates based on stable-element geochemical data are all taken into account. Laboratory measurements include distribution-ratio and diffusion-coefficient determinations. The elements reviewed are carbon, chlorine, calcium, nickel, selenium, strontium, zirconium, niobium, technetium, tin, iodine, caesium, lead, radium, actinium, thorium, protactinium, uranium, neptunium, plutonium, americium and curium. (author)

  19. Radionuclide study for mediastinal tumor

    Energy Technology Data Exchange (ETDEWEB)

    Kawakami, Kenji (Jikei Univ., Tokyo (Japan). School of Medicine); Kubo, Atsushi; Tanabe, Masatada; Ochi, Hironobu; Kusakabe, Kiyoko

    1992-07-01

    {sup 67}Ga scintigraphy has been most available as radionuclide study for mediastinal tumor. Recently {sup 201}Tl scintigraphy is also used to assess the localization and the extent of mediastinal tumor such as thymic tumor, extopic parathyroid tumor, mediastinal metastasis, ect. We surveyed the usefulness of {sup 201}Tl scintigraphy in 24 cases of thymic diseases. Sensitivity of {sup 201}Tl scintigraphy was 100% for thymic diseases, although this method could not differentiate among thymoma, malignant thymoma and thymic hyperplasia. The ability of {sup 201}Tl scintigraphy to detect the metastasis to mediastinal lymph nodes of lung cancer was also high with 100% of sensitivity and 80% of specificity. Applications of {sup 201}Tl scintigraphy for detecting the mediastinal metastasis of parathyroid carcinoma and {sup 131}I-TMBG scintigraphy for the metastasis of medullary carcinoma of the thyroid gland were also discussed. (author).

  20. Decontamination of radionuclides in food

    International Nuclear Information System (INIS)

    Ohmomo, Yoichiro

    1994-01-01

    The release of radionuclides arising from the Chernobyle accident led to widespread contamination of the northern hemisphere through fallout. This accident provided again an opportunity to investigate how and to what extent the radionuclides contamination in crops and animal derived foods could be reduced. The following topics are included in this paper. (1) How to reduce the transfer of radiostrontium and/or cesium from soil to crops: A pH increase of soil is effective for reducing their plant uptake. (2) How to reduce the transfer of radiocesium to animal derived foods: Ammonium-ferric-cyanoferrate (AFCF) should be the most effective compound for radiocesium excretion in the feces. Experiments with lactating cows and/or poultry gave extremely good results with respect to low radiocesium concentrations in milk, meat and eggs. (3) Removal coefficients of radiostrontium, cesium and iodine from contaminated leaf vegetables and cereals during food processing and culinary preparation: Though different by species, more than 80% of cesium and about 50% of strontium and iodine can be removed during culinary preparation of washing and boiling. (4) Simultaneous decontamination of radiocesium and iodine from drinking water and liquid milk: Metal ferrocyanide-anion exchange resin, specifically Fe ferrocyanide one, was successfully used for a rapid and simple decontamination of radiocesium and iodine in the liquid samples arising from the Chernobyle accident. (5) Removal of radiocesium from meat: The meat structurally contaminated with radiocesium is easily and very successfully decontaminated by pickling in NaCl solution and the decontamination is much speeded up by freezing meat before pickling. (author)

  1. Illicit Trafficking of Natural Radionuclides

    Science.gov (United States)

    Friedrich, Steinhäusler; Lyudmila, Zaitseva

    2008-08-01

    Natural radionuclides have been subject to trafficking worldwide, involving natural uranium ore (U 238), processed uranium (yellow cake), low enriched uranium (20% U 235), radium (Ra 226), polonium (Po 210), and natural thorium ore (Th 232). An important prerequisite to successful illicit trafficking activities is access to a suitable logistical infrastructure enabling an undercover shipment of radioactive materials and, in case of trafficking natural uranium or thorium ore, capable of transporting large volumes of material. Covert en route diversion of an authorised uranium transport, together with covert diversion of uranium concentrate from an operating or closed uranium mines or mills, are subject of case studies. Such cases, involving Israel, Iran, Pakistan and Libya, have been analyzed in terms of international actors involved and methods deployed. Using international incident data contained in the Database on Nuclear Smuggling, Theft and Orphan Radiation Sources (DSTO) and international experience gained from the fight against drug trafficking, a generic Trafficking Pathway Model (TPM) is developed for trafficking of natural radionuclides. The TPM covers the complete trafficking cycle, ranging from material diversion, covert material transport, material concealment, and all associated operational procedures. The model subdivides the trafficking cycle into five phases: (1) Material diversion by insider(s) or initiation by outsider(s); (2) Covert transport; (3) Material brokerage; (4) Material sale; (5) Material delivery. An Action Plan is recommended, addressing the strengthening of the national infrastructure for material protection and accounting, development of higher standards of good governance, and needs for improving the control system deployed by customs, border guards and security forces.

  2. Transuranic radionuclides in the environment surrounding radioactive waste diposal sites, a bibliography

    International Nuclear Information System (INIS)

    Stoker, A.C.; Noshkin, V.E.; Wong, K.M.; Brunk, J.L.; Conrado, C.L.; Jones, H.E.; Kehl, S.; Stuart, M.L.; Wasley, L.M.; Bradsher, R.V.

    1994-08-01

    The purpose of this project was to compile a bibliography of references containing environmental transuranic radionuclide data. Our intent was to identify those parameters affecting transuranic radionuclide transport that may be generic and those that may be dependent on chemical form and/or environmental conditions (i.e. site specific). An understanding of the unique characteristics and similarities between source terms and environmental conditions relative to transuranic radionuclide transport and cycling will provide the ability to assess and predict the long term impact on man and the environment. An additional goal of our literature review, was to extract the ranges of environmental transuranic radionuclide data from the identified references for inclusion in a data base. Related to source term, these ranges of data can be used to calculate the dose to man from the radionuclides, and to perform uncertainty analyses on these dose assessments. In an attempt to gather relevant information about the transuranic radionuclides in a variety of environments, we conducted an extensive literature search. In our literature search we identified over 5700 potential written sources of information for review. In addition, we have identified many references which were not found through the literature searches, but which were known to contain useful data. A total of approximately 2600 documents were determined to contain information which would be useful for an in depth study of radionuclides in different environments. The journal articles, books, reports and other documents were reviewed to obtain the source term of the radionuclides studied. Most references containing laboratory study data were not included in our databases. Although these may contain valuable data, we were trying to compile references with information on the behavior of the transuranics in the specific environment being studied

  3. Regulatory Technology Development Plan - Sodium Fast Reactor. Mechanistic Source Term - Metal Fuel Radionuclide Release

    Energy Technology Data Exchange (ETDEWEB)

    Grabaskas, David [Argonne National Lab. (ANL), Argonne, IL (United States); Bucknor, Matthew [Argonne National Lab. (ANL), Argonne, IL (United States); Jerden, James [Argonne National Lab. (ANL), Argonne, IL (United States)

    2016-02-01

    The development of an accurate and defensible mechanistic source term will be vital for the future licensing efforts of metal fuel, pool-type sodium fast reactors. To assist in the creation of a comprehensive mechanistic source term, the current effort sought to estimate the release fraction of radionuclides from metal fuel pins to the primary sodium coolant during fuel pin failures at a variety of temperature conditions. These release estimates were based on the findings of an extensive literature search, which reviewed past experimentation and reactor fuel damage accidents. Data sources for each radionuclide of interest were reviewed to establish release fractions, along with possible release dependencies, and the corresponding uncertainty levels. Although the current knowledge base is substantial, and radionuclide release fractions were established for the elements deemed important for the determination of offsite consequences following a reactor accident, gaps were found pertaining to several radionuclides. First, there is uncertainty regarding the transport behavior of several radionuclides (iodine, barium, strontium, tellurium, and europium) during metal fuel irradiation to high burnup levels. The migration of these radionuclides within the fuel matrix and bond sodium region can greatly affect their release during pin failure incidents. Post-irradiation examination of existing high burnup metal fuel can likely resolve this knowledge gap. Second, data regarding the radionuclide release from molten high burnup metal fuel in sodium is sparse, which makes the assessment of radionuclide release from fuel melting accidents at high fuel burnup levels difficult. This gap could be addressed through fuel melting experimentation with samples from the existing high burnup metal fuel inventory.

  4. Assessment of radionuclides and heavy metals in marine sediments along the Upper Gulf of Thailand

    Science.gov (United States)

    Khuntong, S.; Phaophang, C.; Sudprasert, W.

    2015-05-01

    Due to the Fukushima Daiichi nuclear disaster in 2011 and the development of nuclear power plant in neighboring countries such as Vietnam in the near future, radionuclide assessment in marine sediment during 2010 - 2011 may be useful as background levels for radiation protection in Thailand. Marine sediments (10 samples) were collected approximately 1 km away from the coastline along Chonburi to Pattaya, Chonburi Province. The sediments were ground and sieved through 2-mm test sieve after air drying. Radionuclides were measured with a gamma spectrometer equipped with a well-calibrated HPGe detector. The samples were prepared in the same geometry as the reference material. The optimal counting time was 60,000 - 80,000 s for statistical evaluation and uncertainties. No contamination of 137Cs as an artificial radionuclide was found. Naturally-occurring radionuclides including 238U, 232Th and 40K were found. The mean specific activities of 238U, 232Th and 40K were 44 ± 10, 59 ± 17 and 463 ± 94 Bq/kg in the rainy season (2010); 41 ± 6, 50 ± 9 and 484 ± 83 Bq/kg in the winter (2010), and 39 ± 6, 41 ± 7 and 472 ± 81 Bq/kg in the summer (2011), respectively. The mean specific activities were higher than the values in the UNSCEAR report of 35, 30 and 400 Bq/kg for 238U, 232Th and 40K, respectively. From the measured specific activities, the absorbed dose rate, radium equivalent activity, external hazard index and annual external effective dose rate were calculated in order to assess the health risk. No radiation hazards related to the radioactivity in the sediment were expected. The accumulation of radionuclides varied with the particle size and the organic matter content in the sediment. The accumulation of heavy metals showed similar results to that of the radionuclides in the sediment.

  5. Radionuclides: Accumulation and Transport in Plants.

    Science.gov (United States)

    Gupta, D K; Chatterjee, S; Datta, S; Voronina, A V; Walther, C

    Application of radioactive elements or radionuclides for anthropogenic use is a widespread phenomenon nowadays. Radionuclides undergo radioactive decays releasing ionizing radiation like gamma ray(s) and/or alpha or beta particles that can displace electrons in the living matter (like in DNA) and disturb its function. Radionuclides are highly hazardous pollutants of considerable impact on the environment, food chain and human health. Cleaning up of the contaminated environment through plants is a promising technology where the rhizosphere may play an important role. Plants belonging to the families of Brassicaceae, Papilionaceae, Caryophyllaceae, Poaceae, and Asteraceae are most important in this respect and offer the largest potential for heavy metal phytoremediation. Plants like Lactuca sativa L., Silybum marianum Gaertn., Centaurea cyanus L., Carthamus tinctorius L., Helianthus annuus and H. tuberosus are also important plants for heavy metal phytoremediation. However, transfer factors (TF) of radionuclide from soil/water to plant ([Radionuclide]plant/[Radionuclide]soil) vary widely in different plants. Rhizosphere, rhizobacteria and varied metal transporters like NRAMP, ZIP families CDF, ATPases (HMAs) family like P1B-ATPases, are involved in the radio-phytoremediation processes. This review will discuss recent advancements and potential application of plants for radionuclide removal from the environment.

  6. Radionuclides in air, water, and biota

    International Nuclear Information System (INIS)

    Seymour, A.H.; Nelson, V.A.

    1977-01-01

    Air, water, and biological samples collected before and after the 1965, 1969, and 1971 underground nuclear detonations at Amchitka Island were analyzed for natural and fallout radionuclides by gamma spectrometry. Selected samples were also analyzed for tritium, 55 Fe, and 90 Sr. The objectives were to search for and identify radionuclides of Amchitka origin in the samples and to contribute to the general knowledge of the distribution of radionuclides in the environment. The studies showed that there has been no escape of radionuclides from the underground sites of the three nuclear detonations at Amchitka Island except for trace quantities of radionuclides, principally tritium, in water and soil gas samples from the immediate vicinity of the surface ground zero for the 1965 event. Two naturally occurring radionuclides, 40 K and 7 Be, were the most abundant radionuclides in the samples, usually by a factor of 10 or more, except for 137 Cs in lichen samples. All levels were well below applicable Radiation Protction Guides, often being near the statistical limit of detection

  7. Automation of radionuclide analysis in nuclear industry

    International Nuclear Information System (INIS)

    Gostilo, V.; Sokolov, A.; Kuzmenko, V.; Kondratjev, V.

    2009-01-01

    The development results for the automated precise HPGe spectrometers and systems for radionuclide analyses in nuclear industry and environmental monitoring are presented. Automated HPGe spectrometer for radionuclide monitoring of coolant in primary circuit of NPPs is intended for technological monitoring of the radionuclide specific activity in liquid and gaseous flows in the on-line mode. The automated spectrometer based on flowing HPGe detector with the through channel is intended for control of the uniformity of distribution of uranium and/or plutonium in fresh fuel elements, transferred through the detector, as well as for on-line control of the fluids and gases flows with low activity. Automated monitoring system for radionuclide volumetric activity in outlet channels of NPPs is intended for radionuclide monitoring of water reservoirs in the regions of nuclear weapons testing, near nuclear storage, nuclear power plants and other objects of nuclear energetic. Autonomous HPGe spectrometer for deep water radionuclide monitoring is applicable for registration of gamma radionuclides, distributed in water depth up to 3000 m (radioactive wastes storage, wreck of atomic ships, lost nuclear charges, atomic industry technological waste release etc.).(authors)

  8. Regional survey of radionuclides in the marine environment of the French Mediterranean coast

    Energy Technology Data Exchange (ETDEWEB)

    Thebault, Herve; Arnaud, Mireille; Duffa, Celine; Charmasson, Sabine; Dimeglio, Yves [Institut de Radioprotection et de Surete Nucleaire/PRP-ENV/SESURE/LERCM/ARM c/o Ifremer, CS 20330 Zone Portuaire de Bregaillon, 83507 La Seyne sur Mer Cedex (France)

    2014-07-01

    The French Institute for Radioprotection and Nuclear Safety (IRSN) runs a continuous monitoring program of the marine environment as a mandatory task. For the French Mediterranean coast, this monitoring activity focuses on two bio-indicators species: the Mediterranean mussel (Mytilus galloprovincialis) and the red mullet (Mullus sp.) sampled on a regular basis from natural populations at ten locations along the coast. Radionuclides are measured using direct low-level gamma spectrometry as a routine technique. In addition to this long-lasting monitoring, a broad survey of radionuclide baseline levels is conducted on all compartments of the coastal zone: water, sediments and a large selection of fish species among those most currently fished and marketed. This extended data collection is necessary to fulfill the information requirements of the UE Marine Strategy Framework Directive (MSFD) and its implementation by member states. This information is also essential for impact assessment of any incident or accident, included from a remote source. Levels of less commonly measured radionuclides like {sup 3}H, {sup 14}C, {sup 90}Sr, {sup 210}Po and U, Pu isotopes are investigated. Fish sampling relies mostly on scientific stock assessment campaigns. Mussel sampling is complemented by transplanted mussels on 40 specific sites. This regional survey also focuses on two possibly impacted areas: the Rhone river mouth coastal zone, with inputs from nuclear power plants along the river and the Bay of Toulon sheltering Navy harbor of nuclear-powered sub-marines and aircraft-carrier. First results show that the activity levels of artificial radionuclides are very low for most bio-indicator species, in accordance with previous monitoring trends. {sup 137}Cs is the only artificial radionuclide regularly detected by gamma spectrometry in mussel and fish samples at a level below 1 Bg.kg{sup -1} of dry weight. Values of {sup 3}H (organically bound Tritium) in the same samples lies under

  9. Therapeutic radionuclides: Production and decay property considerations

    International Nuclear Information System (INIS)

    Volkert, W.A.; Goeckeler, W.F.; Ehrhardt, G.J.; Ketring, A.R.

    1991-01-01

    The development of effective therapeutic radiopharmaceuticals requires careful consideration in the selection of the radionuclide. The in vivo targeting and clearance properties of the carrier molecule must be balanced with the decay properties of the attached radionuclide. Radionuclides for therapeutic applications fall into three general categories: beta-particle emitters, alpha-particle emitters, and Auger and Coster-Kronig-electron emitters following electron capture. Alpha particles and Auger electrons deposit their energy over short distances with a high LET that limits the ability of cells to repair damage to DNA. Despite their high levels of cytotoxicity, the relatively short range of alpha particles requires binding of the carrier molecule to most cancer cells within a tumor in order to be effective. Because of the extremely short range of Auger electrons, the radionuclide must be carried directly into the nucleus to elicit high radiotoxicity, making it necessary to deliver the radionuclide to every cell within a tumor cell population. These characteristics impose rigid restrictions on the nature of the carrier molecules for these types of particle emitters but successful targeting of these types of radionuclides could result in high therapeutic ratios. Most beta-emitting radionuclides are produced in nuclear rectors via neutron capture reactions; however, a few are produced in charged-particle accelerators. For radionuclides produced by direct neutron activation, the quantities and specific activities that can be produced are determined in large part by the cross-section of the target isotope and the flux of the reactor. Many applications do not require high-specific activities and can therefore utilize the wide range of radionuclides that can be produced in sufficient quantity by direct neutron activation. 114 refs

  10. 2008 LANL radionuclide air emissions report

    Energy Technology Data Exchange (ETDEWEB)

    Fuehne, David P.

    2009-06-01

    The emissions of radionuclides from Department of Energy Facilities such as Los Alamos National Laboratory (LANL) are regulated by the Amendments to the Clean Air Act of 1990, National Emissions Standards for Hazardous Air Pollutants (40 CFR 61 Subpart H). These regulations established an annual dose limit of 10 mrem to the maximally exposed member of the public attributable to emissions of radionuclides. This document describes the emissions of radionuclides from LANL and the dose calculations resulting from these emissions for calendar year 2008. This report meets the reporting requirements established in the regulations.

  11. 2010 LANL radionuclide air emissions report /

    Energy Technology Data Exchange (ETDEWEB)

    Fuehne, David P.

    2011-06-01

    The emissions of radionuclides from Department of Energy Facilities such as Los Alamos National Laboratory (LANL) are regulated by the Amendments to the Clean Air Act of 1990, National Emissions Standards for Hazardous Air Pollutants (40 CFR 61 Subpart H). These regulations established an annual dose limit of 10 mrem to the maximally exposed member of the public attributable to emissions of radionuclides. This document describes the emissions of radionuclides from LANL and the dose calculations resulting from these emissions for calendar year 2010. This report meets the reporting requirements established in the regulations.

  12. Current potential of radionuclide applications in therapy

    International Nuclear Information System (INIS)

    Navratil, L.

    1987-01-01

    A review is presented of the proceedings of the 4th Boettstein Collegium held in June, 1986 in Wuerenlingen (CH), debating new possibilities in applying radionuclides in the therapy of malignant diseases. The new possibilities are open with the development of new biological carriers with high detection capacities, especially monoclonal antibodies. Therapeutical applications are characterized of some radionuclides, mainly 131 I and 123 I, and beta and alpha radionuclides are listed promising for therapeutical uses. Therapeutical prospects are also outlined for immunotherapy. (L.O.). 1 ref

  13. DNA damage induced by radionuclide internal irradiation

    International Nuclear Information System (INIS)

    Cui Fengmei; Zhao Jingyong; Hong Chengjiao; Lao Qinhua; Wang Liuyi; Yang Shuqin

    2004-01-01

    Objective: To study the DNA damage of peripheral blood mononuclear cell (PBMC) in rats exposed to radionuclide internal irradiation. Methods: The radionuclides were injected into the rats and single cell get electrophoresis (SCGE) was performed to detect the length of DNA migration in the rat PBMC. Results: DNA migration in the rat PBMC increased with accumulative dose or dose-rate. It showed good relationship of dose vs. response and of dose-rate vs. response, both relationship could be described as linear models. Conclusion: Radionuclide internal irradiation could cause DNA damage in rat PBMC. (authors)

  14. Solubility limited radionuclide transport through geologic media

    International Nuclear Information System (INIS)

    Muraoka, Susumu; Iwamoto, Fumio; Pigford, T.H.

    1980-11-01

    Prior analyses for the migration of radionuclides neglect solubility limits of resolved radionuclide in geologic media. But actually some of the actinides may appear in chemical forms of very low solubility. In the present report we have proposed the migration model with no decay parents in which concentration of radionuclide is limited in concentration of solubility in ground water. In addition, the analytical solutions of the space-time-dependent concentration are presented in the case of step release, band release and exponential release. (author)

  15. Soil - plant experimental radionuclide transfer factors

    International Nuclear Information System (INIS)

    Dobrin, R.I.; Dulama, C.N.; Toma, Al.

    2006-01-01

    Some experimental research was performed in our institute to assess site specific soil-plant transfer factors. A full characterization of an experimental site was done both from pedo-chemical and radiological point of view. Afterwards, a certain number of culture plants were grown on this site and the evolution of their radionuclide burden was then recorded. Using some soil amendments one performed a parallel experiment and the radionuclide root uptake was evaluated and recorded. Hence, transfer parameters were calculated and some conclusions were drawn concerning the influence of site specific conditions on the root uptake of radionuclides. (authors)

  16. Medium-Detail Delta Morphodynamic Modeling: Initial Experiments with Avulsion Behaviors, Sediment Delivery, Artificial Leeves, and Relative Sea Level Rise Rates

    Science.gov (United States)

    Ratliff, K. M.; Murray, A. B.; Hutton, E. W. H.; Piliouras, A.; Kim, W.

    2014-12-01

    Deltas and their flat, fertile lands have become the most densely populated places on earth, but, partly because of anthropogenic interactions with fluvial, coastal, and wetland processes, their inhabitants are increasingly susceptible to natural disasters. Humans have decreased sediment supply delivered to rivers and ultimately wetlands and the coast, causing accelerating subsidence. The natural course and processes of many rivers have been altered through channelization, artificial levees, and dams, which 'perch' the river above its floodplain. As the rate of relative sea-level rise (RSLR) increases, so will surface aggradation and channel backfilling, resulting in a fluvial system that is more vulnerable to flooding and frequent avulsions. To investigate the effects of increasing RSLR and anthropogenic manipulations on delta morphodynamics, we create new avulsion and floodplain modules to couple with the 3D mode of Sedflux (Hutton and Syvitski, 2008), a stratigraphic basin-filling model. We replace the probabilistic approach of channel avulsion previously used in the model with a module incorporating the steepest-decent methodology used in Jerolmack and Paola (2007), and a floodplain algorithm to deposit sediment on subaerial cells. Model experiments with Sedflux and the new modules address the effects on delta morphodynamics of varying rates of RSLR (affecting base-level), changes in sediment delivery (adjusting the upstream boundary conditions), and restriction of natural fluvial dynamics (inhibiting avulsions). The work presented here is the first step in a more expansive project to develop a new 3D eco-morphodynamic delta model system that will be based on further model couplings, including a vegetation module (that will affect fluvial and floodplain dynamics) and a coastline module (that will re-work the shoreline based on wave-driven alongshore sediment transport). The model system results will be tested and calibrated based on comparisons with

  17. Artificial Intelligence in Astronomy

    Science.gov (United States)

    Devinney, E. J.; Prša, A.; Guinan, E. F.; Degeorge, M.

    2010-12-01

    From the perspective (and bias) as Eclipsing Binary researchers, we give a brief overview of the development of Artificial Intelligence (AI) applications, describe major application areas of AI in astronomy, and illustrate the power of an AI approach in an application developed under the EBAI (Eclipsing Binaries via Artificial Intelligence) project, which employs Artificial Neural Network technology for estimating light curve solution parameters of eclipsing binary systems.

  18. Quo Vadis, Artificial Intelligence?

    OpenAIRE

    Berrar, Daniel; Sato, Naoyuki; Schuster, Alfons

    2010-01-01

    Since its conception in the mid 1950s, artificial intelligence with its great ambition to understand and emulate intelligence in natural and artificial environments alike is now a truly multidisciplinary field that reaches out and is inspired by a great diversity of other fields. Rapid advances in research and technology in various fields have created environments into which artificial intelligence could embed itself naturally and comfortably. Neuroscience with its desire to understand nervou...

  19. Artificial cognition architectures

    CERN Document Server

    Crowder, James A; Friess, Shelli A

    2013-01-01

    The goal of this book is to establish the foundation, principles, theory, and concepts that are the backbone of real, autonomous Artificial Intelligence. Presented here are some basic human intelligence concepts framed for Artificial Intelligence systems. These include concepts like Metacognition and Metamemory, along with architectural constructs for Artificial Intelligence versions of human brain functions like the prefrontal cortex. Also presented are possible hardware and software architectures that lend themselves to learning, reasoning, and self-evolution

  20. Research progess on treatment of cancer with targeted radionuclide therapy

    International Nuclear Information System (INIS)

    Luo Jiawen; Zhang Caixia

    2008-01-01

    The new development and situation of targeted radionuclide therapy in oncology is described, which include radioimmunotherapy, peptide receptor radionuclide therapy, gene therapy and radionuclide labled chemotherapeutics therapy. The application research on labled carrier of those therapy is emphasized. Meanwhile, the research progess of indomethacin and its combined with targeted radionuclide therapy is also described. (authors)

  1. Radionuclide Generators: New Systems for Nuclear Medicine Applications

    International Nuclear Information System (INIS)

    Knapp, F.F.; Butler, T.A.

    1984-01-01

    This book reviews and discusses in detail the new generation and improved versions of older radionuclide generators that are being developed for nuclear medicine applications. Short-lived radionuclides, positron-emitting radionuclides, and radionuclide production and miscellaneous applications are studied

  2. An artificial muscle computer

    Science.gov (United States)

    Marc O'Brien, Benjamin; Alexander Anderson, Iain

    2013-03-01

    We have built an artificial muscle computer based on Wolfram's "2, 3" Turing machine architecture, the simplest known universal Turing machine. Our computer uses artificial muscles for its instruction set, output buffers, and memory write and addressing mechanisms. The computer is very slow and large (0.15 Hz, ˜1 m3); however by using only 13 artificial muscle relays, it is capable of solving any computable problem given sufficient memory, time, and reliability. The development of this computer shows that artificial muscles can think—paving the way for soft robots with reflexes like those seen in nature.

  3. Experimental Studies to Evaluate the Role of Colloids on the Radionuclide Migration in a Crystalline Medium

    Energy Technology Data Exchange (ETDEWEB)

    Albarran, Nairoby; Missana, Tiziana; Alonso, Ursula; Garcia-Gutierrez, Miguel; Mingarro, Manuel; Lopez, Trinidad [CIEMAT, Departamento de Medioambiente, Avenida Complutense, 22 28040 Madrid (Spain)

    2008-07-01

    In a deep geological repository (DGR) of high level radioactive waste, all the possible phenomena affecting radionuclide migration have to be studied to assess its security over time. Colloids can play an important role for contaminant transport if the following conditions are fulfilled: colloids exist in a non negligible concentration, they are mobile and stable in the environment of interest, and they are able to adsorb radionuclides irreversibly. In this study, different transport experiments where performed to improve the knowledge on the main mechanisms affecting the radionuclide migration in the presence of colloids in a crystalline medium. Firstly, colloid stability was analysed and then transport experiments in an artificial granite longitudinal fracture were carried out. Synthetic colloids of different size and bentonite clay colloids were used to evaluate the effects of colloid size, charge, and water flow rate on their mobility. Results showed that both major importance of the water flow rate on the mobility of colloids and their recovery and a higher interaction of smaller particles with the surface. Finally, the migration behaviour of Sr, and Sr adsorbed onto bentonite colloids was compared. The elution curves of Sr adsorbed onto colloid were significantly different from the ones of Sr alone, pointing out that sorption/desorption mechanisms must be taken into account to understand the radionuclide migration in the fracture in the presence of colloids. (authors)

  4. Determination of Radionuclide Concentrations in Tea Samples Cultivated in Guilan Province, Iran

    Directory of Open Access Journals (Sweden)

    Zahra Poursharif

    2016-04-01

    Full Text Available Introduction Foodstuffs are known to contain natural and artificial radionuclides. Determination of radionuclide concentration is of great significance for the protection of human health. The main objective of the present study was the quantification of radionuclides in tea samples, cultivated in Guilan Province in North of Iran. Materials and Methods The activity concentrations of 226Ra, 232Th, 40K, and 137Cs in 18 tea samples were measured, using a gamma spectrometry system. In addition, radium equivalent index (Raeq and radiation hazard index (HI were calculated. ANOVA test was used for the statistical analysis of the data Results The concentration of 137Cs was below the minimum detectable activity (MDA. The concentrations of 226Ra and 232Th ranged from < MDA to 0.042 and < MDA to 0.037  Bq/kg respectively. The mean concentration of 40K was 410±15  Bq/kg. Based on the findings, the concentration of 40K was significantly higher than other radionuclides (P

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

    International Nuclear Information System (INIS)

    Hoffman, D.C.; Daniels, W.R.

    1984-01-01

    A field study of the distribution of radionuclides around an underground nuclear explosion cavity was initiated in 1974, about 9 years after detonation of the nuclear test. This study is part of the Radionuclide Migration (RNM) Project, a broad investigation to determine the rates of migration underground in various media at the Nevada Test Site (NTS) and the potential for movement both on and off the NTS of radioactivity from underground nuclear explosions. It was also envisaged that the study might provide data applicable to the underground disposal of radioactive waste. The site of the 0.75 kiloton nuclear test Cambric was chosen for a number of reasons. The Cambric explosion cavity is within the NTS Area 5 water-supply aquifer, and there was particular interest in possible contamination of water supplies. Also, the Cambric detonation point is only 294 meters below the ground surface, and thus the re-entry drilling and sampling operations would be less difficult and expensive than from some of the more deeply buried tests. The Cambric cavity region was re-entered, and a well was completed to a depth of 370 meters. Samples were taken to determine the radionuclide distribution between the solid material and water at the time of the experiment was started. Water was then pumped from a nearby satellite well to induce an artificial gradient sufficient to draw water from the Cambric cavity and provide an opportunity for the study of radionuclide migration under field conditions

  6. Application of of artificial neural networks for estimation of soil-plant transfer factor for 137Cs

    International Nuclear Information System (INIS)

    Santos, Anna Karla Gomes dos

    2016-01-01

    The knowledge of radionuclide behavior in soils is fundamental to calculate the dose due to food ingestion and to evaluate the risks of radioactive exposure of the population. This knowledge associated to the socio-economic characteristics of the affected region will set the radio protective measures to be taken in case of radioactive contamination of rural areas. The soil-plant transfer factor (TF) is the specific parameter value of radiological models to numerically integrate the dynamic processes that occur within the radionuclides in the soil plant system. This measurement, specific to each radionuclide and soil type, is defined ratio between a specific radionuclide activity in the edible part of the plant and its soil activity. However, the absence of linearity between soil concentrations and the measurements in plants indicate the complexity of the transfer process of radionuclide from soil to a plant, making it difficult to forecast the TF ratio in a specific scenario. One of the main radionuclides associated to nuclear accidents impacting rural areas is 137 Cs. This is one of the most worrisome radionuclides because of its physiochemical properties and its chemical similarity with potassium (K) and its extended physical mid-life (t1/2 = 30,17 years) that allows great environmental dispersion, ecological mobility and environmental endurance. Radiological studies related to 137 Cs transfer factor show that pedological parameters that considerably explain the behavior of 137 Cs in soil-plant system are: exchangeable K, clayed minerals, organic matter content and pH in soils. In this work, the computational method of artificial neural network (ANN) was applied to evaluate the possibility to forecast the TF of 137 Cs in cereals, associated to pedological parameters considered potential indicators of its phyto availability: cationic exchange capacity (CEC), exchangeable K and pH. This study demonstrated that the ANN, having only as entry data the pedological

  7. Artificial intelligence in medicine.

    Science.gov (United States)

    Hamet, Pavel; Tremblay, Johanne

    2017-04-01

    Artificial Intelligence (AI) is a general term that implies the use of a computer to model intelligent behavior with minimal human intervention. AI is generally accepted as having started with the invention of robots. The term derives from the Czech word robota, meaning biosynthetic machines used as forced labor. In this field, Leonardo Da Vinci's lasting heritage is today's burgeoning use of robotic-assisted surgery, named after him, for complex urologic and gynecologic procedures. Da Vinci's sketchbooks of robots helped set the stage for this innovation. AI, described as the science and engineering of making intelligent machines, was officially born in 1956. The term is applicable to a broad range of items in medicine such as robotics, medical diagnosis, medical statistics, and human biology-up to and including today's "omics". AI in medicine, which is the focus of this review, has two main branches: virtual and physical. The virtual branch includes informatics approaches from deep learning information management to control of health management systems, including electronic health records, and active guidance of physicians in their treatment decisions. The physical branch is best represented by robots used to assist the elderly patient or the attending surgeon. Also embodied in this branch are targeted nanorobots, a unique new drug delivery system. The societal and ethical complexities of these applications require further reflection, proof of their medical utility, economic value, and development of interdisciplinary strategies for their wider application. Copyright © 2017. Published by Elsevier Inc.

  8. A review on studies of the transport and the form of radionuclides in the fluvial environment

    Energy Technology Data Exchange (ETDEWEB)

    Matsunaga, Takeshi [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    2001-06-01

    The Japan Atomic Energy Research Institute has conducted studies with an aim to contribute to understanding the long-term behavior of atmospherically-derived radionuclides deposited on the ground. The present report reviews a series of studies among them which have especially dealt with the behavior of those radionuclides in a fluvial environment. The studies cited here include investigations of 1) the evaluation of the transport rate of the atmospherically-derived radionuclides from the ground via a river to the downstream areas where the affected water is consumed; 2) the physico-chemical form of the radionuclides in the fluvial environment. An investigation in the Kuji river watershed with {sup 137}Cs, {sup 210}Pb and {sup 7}Be has validated i) the importance of suspended particulate materials in the fluvial discharge of those radionuclides, and ii) a methodology to estimate the discharge of those radionuclides based on the regression analysis with the river water flow rate. From a viewpoint of their distribution between water and suspended particles, the form of radionuclides released by the Chernobyl accident in rivers and lakes in the vicinity of the Chernobyl Nuclear Power Plant were analyzed. As a result, a general reasonability and some cautions were suggested when commonly reported distribution ratios obtained in the laboratory and the different environment are applied to describe the partitioning of the radionuclides in specific natural environmental conditions. This experimental investigation in Chernobyl also revealed the role of natural dissolved organics in affecting the dissolution and transport of {sup 239,240}Pu, {sup 241}Am through complexation to form soluble species. Further, a chemical equilibrium model was applied to describe this complexation. The similar model was also applied for the behavior of iron and manganese (hydr)oxides in river recharged aquifers which can bear riverborne radionuclides and can influence their migration. The

  9. National Low-Level Waste Management Program Radionuclide Report Series, Volume 17: Plutonium-239

    Energy Technology Data Exchange (ETDEWEB)

    J. P. Adams; M. L. Carboneau

    1999-03-01

    This report, Volume 17 of the National Low-Level Waste Management Program Radionuclide Report Series, discusses the radiological and chemical characteristics of plutonium-239 (Pu-239). This report also discusses waste types and forms in which Pu-239 can be found, waste and disposal information on Pu-239, and Pu-239 behavior in the environment and in the human body.

  10. National Low-Level Waste Management Program Radionuclide Report Series, Volume 17: Plutonium-239

    International Nuclear Information System (INIS)

    Adams, J.P.; Carboneau, M.L.

    1999-01-01

    This report, Volume 17 of the National Low-Level Waste Management Program Radionuclide Report Series, discusses the radiological and chemical characteristics of plutonium-239 (Pu-239). This report also discusses waste types and forms in which Pu-239 can be found, waste and disposal information on Pu-239, and Pu-239 behavior in the environment and in the human body

  11. Radionuclide imaging of musculoskeletal infection

    Directory of Open Access Journals (Sweden)

    Christopher J. Palestro

    2007-09-01

    Full Text Available Radionuclide imaging studies are routinely used to evaluate patients suspected of having musculoskeletal infection. Three-phase bone imaging is readily available, relatively inexpensive, and very accurate in the setting of otherwise normal bone. Labeled leukocyte imaging should be used in cases of "complicating osteomyelitis" such as prosthetic joint infection. This test also is useful in clinically unsuspected diabetic pedal osteomyelitis as well as in the neuropathic joint. It is often necessary, however, to perform complementary bone marrow imaging, to maximize the accuracy of labeled leukocyte imaging. In contrast to other regions in the skeleton, labeled leukocyte imaging is not useful for diagnosing spinal osteomyelitis. At the moment, gallium is the preferred radionuclide procedure for this condition and is a useful adjunct to magnetic resonance imaging. FDG-PET likely will play an important role in the evaluation of musculoskeletal infection, especially spinal osteomyelitis, and may replace gallium imaging for this purpose.Estudos através de imagens com o uso de radionuclídeos são rotineiramente usadas para avaliar pacientes suspeitos de terem infecção músculo-esquelética. A imagem óssea em tridimensional é facilmente avaliável, relativamente de baixo custo, e muito precisa na localização de alterações ósseas. Imagem com leucócito marcado poderia ser usada nos casos de "osteomielite com complicações" tais como infecção prostética articular. Esse teste também é útil na não suspeita clinica de osteomielite associada ao pé diabético tanto quanto nas junções neuropáticas. É sempre necessário, por outro lado, realizar imagem complementar da medula óssea para aumentar a precisão da imagem com leucócito marcado. Em contraste com outras regiões no esqueleto, imagem com leucócito marcado não é útil para diagnosticar osteomielite da coluna vertebral. Até agora, o gálio é o radionuclídeo preferido para

  12. Options to meet the future global demand of radionuclides for radionuclide therapy

    International Nuclear Information System (INIS)

    Das, Tapas; Pillai, M.R.A.

    2013-01-01

    Nuclear medicine continues to represent one of the important modalities for cancer management. While diagnostic nuclear medicine for cancer management is fairly well established, therapeutic strategies using radionuclides are yet to be utilized to their full potential. Even if 1% of the patients undergoing diagnostic nuclear medicine procedures can benefit from subsequent nuclear therapeutic intervention, the radionuclide requirement for nuclear therapeutics would be expected to be in the multi-million Curie levels. Meeting the demand for such high levels of therapeutic radionuclides at an affordable price is an important task for the success of radionuclide therapy. Although different types of particle emitters (beta, alpha, Auger electron etc.) have been evaluated for treating a wide variety of diseases, the use of β − emitting radionuclides is most feasible owing to their ease of production and availability. Several β − emitting radionuclides have been successfully used to treat different kind of diseases. However, many of these radionuclides are not suitable to meet the projected demand owing to the non-availability with sufficiently high specific activity and adequate quantity because of high production costs, relatively short half-lives etc. This article describes the advantages and disadvantages for broader uses of some of the well known therapeutic radionuclides. In addition, radioisotopes which are expected to have the potential to meet the growing demand of therapeutic radionuclides are also discussed.

  13. Options to meet the future global demand of radionuclides for radionuclide therapy.

    Science.gov (United States)

    Das, Tapas; Pillai, M R A

    2013-01-01

    Nuclear medicine continues to represent one of the important modalities for cancer management. While diagnostic nuclear medicine for cancer management is fairly well established, therapeutic strategies using radionuclides are yet to be utilized to their full potential. Even if 1% of the patients undergoing diagnostic nuclear medicine procedures can benefit from subsequent nuclear therapeutic intervention, the radionuclide requirement for nuclear therapeutics would be expected to be in the multi-million Curie levels. Meeting the demand for such high levels of therapeutic radionuclides at an affordable price is an important task for the success of radionuclide therapy. Although different types of particle emitters (beta, alpha, Auger electron etc.) have been evaluated for treating a wide variety of diseases, the use of β⁻ emitting radionuclides is most feasible owing to their ease of production and availability. Several β⁻ emitting radionuclides have been successfully used to treat different kind of diseases. However, many of these radionuclides are not suitable to meet the projected demand owing to the non-availability with sufficiently high specific activity and adequate quantity because of high production costs, relatively short half-lives etc. This article describes the advantages and disadvantages for broader uses of some of the well known therapeutic radionuclides. In addition, radioisotopes which are expected to have the potential to meet the growing demand of therapeutic radionuclides are also discussed. Copyright © 2013 Elsevier Inc. All rights reserved.

  14. Transfer of radionuclides into human milk

    International Nuclear Information System (INIS)

    Steiner, M.; Wirth, E.

    1998-01-01

    Up until now the potential radiation exposure to breast-fed babies due to contaminated human milk has not been taken into account, when deriving international limit values and reference levels for radionuclides in foodstuffs, in air at monitored work places or for exposures in the medical field. It was the aim of the research project 'Transfer of radionuclides into human milk' to quantify the transfer of incorporated radionuclides into mother's milk, and develop simple models to estimate the radiation exposure of babies through the ingestion of human milk. The study focused on considerations of the radiation exposure due to the ingestion of contaminated foodstuffs by the mother, the inhalation of radionuclides at monitored work places, and the administration of radiopharmaceuticals to breast-feeding mothers. The blocking of infant thyroid glands by stable iodine in the case of accidental releases of radioiodine was considered as well. (orig.) [de

  15. Phytoremediation of soils contaminated with radionuclides

    International Nuclear Information System (INIS)

    Yamaguchi, Isamu

    2004-01-01

    Aiming at efficient phytoremediation of soils contaminated with radionuclides, we examined the effect of soil microbes on the uptake ability of plants using the multitracer technique to find that tomato rhizofungi in Fusarium spp. can stimulate the uptake of 85 Sr and 137 Cs by the plants. The synergic effect of a nonpathogenic strain of F. oxysporum on the uptake of radionuclides by plants proved to be enhanced by introducing a phytochelatin synthase gene into the fungus. Since soil contamination by radionuclides is still an unsolved problem in many parts of the world. Studies on phytoremediation of polluted soil environment will be important for developing effective strategies and devising adequate techniques to reduce human risks caused by food contamination of radionuclides. (author)

  16. System and method for assaying a radionuclide

    Energy Technology Data Exchange (ETDEWEB)

    Cadieux, James R; King, III, George S; Fugate, Glenn A

    2014-12-23

    A system for assaying a radionuclide includes a liquid scintillation detector, an analyzer connected to the liquid scintillation detector, and a delay circuit connected to the analyzer. A gamma detector and a multi-channel analyzer are connected to the delay circuit and the gamma detector. The multi-channel analyzer produces a signal reflective of the radionuclide in the sample. A method for assaying a radionuclide includes selecting a sample, detecting alpha or beta emissions from the sample with a liquid scintillation detector, producing a first signal reflective of the alpha or beta emissions, and delaying the first signal a predetermined time. The method further includes detecting gamma emissions from the sample, producing a second signal reflective of the gamma emissions, and combining the delayed first signal with the second signal to produce a third signal reflective of the radionuclide.

  17. Natural and anthropogenic radionuclides in the environment

    International Nuclear Information System (INIS)

    Hille, R.

    1984-01-01

    A survey is given on the actual knowledge about occurence and environmental relevancy of the most important radionuclides from natural and anthropogenic origin. The contribution of AGF installation is emphasized. (orig.) [de

  18. Computed tomography and radionuclide brain scanning

    International Nuclear Information System (INIS)

    Lusins, J.O.; Chayes, Z.; Nakagawa, H.

    1980-01-01

    A comparison o CT (computerized Tomography) and radionuclide brain scanning was performed; 30 patients with a total of 42 lesions were evaluated. Previous sreports have shown that CT and radionuclide scanning are equally useful in detecting metastatic disease. However, if contrast enhancement is used we find that computerized tomography is far more accurate than radionuclide scanning in detecting metastatic disease to the brain, 95.4 percent as compared to 62 percent. Our study also shows that radionuclide scanning falls off in accuracy when the the lesion is below 2 cm. in size. Also, the presence of brain edema in association with metastatic disease increases the probability of having a positive nuclear scan finding

  19. Rearing the southern green stink bug using an artificial dry diet and an artificial plant

    Energy Technology Data Exchange (ETDEWEB)

    Panizzi, Antonio Ricardo [EMBRAPA, Londrina, PR (Brazil). Centro Nacional de Pesquisa de Soja]. E-mail: Panizzi@cnpso.embrapa.br; Parra, Jose Roberto Postali; Carvalho, Diogo Rodrigues [Universidade de Sao Paulo (USP), Piracicaba, SP (Brazil). Escola Superior de Agricultura Luiz de Queiroz (ESALQ). Dept. Entomologia, Fitopatologia e Zoologia Agricola]. E-mail: jrpparra@carpa.ciagri.usp.br; E-mail: drcarval@carpa.ciagri.usp.br; Santos, Claudia Hirt [Universidade Federal do Parana (UFPR), Curitiba (Brazil)]. E-mail: clauhirt@yahoo.com.br

    2000-09-15

    Laboratory and greenhouse studies were conducted with an artificial dry diet to rear nymphs, and with an artificial plant as substrate for egg laying by the southern green stink bug, Nezara viridula (L.). The artificial diet was composed of: soybean protein (15 g); potato starch (7.5 g); dextrose (7.5 g); sucrose (2.5 g); cellulose (12.5 g); vitamin mixture (niacinamide 1 g, calcium pantothenate 1 g, thiamine 0.25 g, riboflavin 0.5 g, pyridoxine 0.25 g, folic acid 0.25 g, biotin 0.02 mL, vitamin B12 1 g - added to 1,000 mL of distilled water) (5.0 mL); soybean oil (20 mL); wheat germ (17.9 g); and water (30 mL). Nymphs showed normal feeding behavior when fed on the artificial diet. Nymphal development time was longer than or similar to that of nymphs fed on soybean pods. Total nymphal mortality was low (ca. 30%), both for nymphs reared on the artificial diet, and for nymphs fed on soybean pods. At adult emergence, fresh body weights were significantly (P<0.01) less on the artificial diet than on soybean pods. Despite the lower adult survivorship and fecundity on artificial plants than on soybean plants, it was demonstrated for the first time that a model simulating a natural plant, can be used as a substrate for egg mass laying, in conjunction with the artificial diet. (author)

  20. Natural and Synthetic Barriers to Immobilize Radionuclides

    International Nuclear Information System (INIS)

    Um, W.

    2011-01-01

    The experiments of weathering of glass waste form and the reacted sediments with simulated glass leachates show that radionuclide sequestration can be significantly enhanced by promoting the formation of secondary precipitates. In addition, synthetic phosphate-bearing nanoporous material exhibits high stability at temperature and has a very high K d value for U(VI) removal. Both natural and synthetic barrier materials can be used as additional efficient adsorbents for retarding transport of radionuclides for various contaminated waste streams and waste forms present at U. S. Department of Energy clean-up sites and the proposed geologic radioactive waste disposal facility. In the radioactive waste repository facility, natural or synthetic materials are planned to be used as a barrier material to immobilize and retard radionuclide release. The getter material can be used to selectively scavenge the radionuclide of interest from a liquid waste stream and subsequently incorporate the loaded getters in a cementitious or various monolithic waste forms. Also, the getter material is to reduce the release of radionuclides from monolithic waste forms. Also, the getter material is to reduce the release of radionuclides from monolithic waste forms. Also, the getter material is to reduce the release of radionuclides form monolithic waste forms by being emplaced as a backfill barrier material around the wastes or waste form to minimize the potential around the wastes or waste form to minimize the potential hazard of leached radioactive wastes. The barrier material should be highly efficient to sequester radionuclides and possess physical and chemical stability for long-term exposure to severe weathering conditions. Because potential leaching of radionuclides depends on various environmental and weathering conditions of the near-field repository, the barrier materials must be durable and not disintegrate under a range of moisture, temperature, pressure, radiation, Eh, ph. and

  1. Social interactions between live and artificial weakly electric fish: Electrocommunication and locomotor behavior of Mormyrus rume proboscirostris towards a mobile dummy fish.

    Directory of Open Access Journals (Sweden)

    Martin Worm

    Full Text Available Mormyrid weakly electric fish produce short, pulse-type electric organ discharges for actively probing their environment and to communicate with conspecifics. Animals emit sequences of pulse-trains that vary in overall frequency and temporal patterning and can lead to time-locked interactions with the discharge activity of other individuals. Both active electrolocation and electrocommunication are additionally accompanied by stereotypical locomotor patterns. However, the concrete roles of electrical and locomotor patterns during social interactions in mormyrids are not well understood. Here we used a mobile fish dummy that was emitting different types of electrical playback sequences to study following behavior and interaction patterns (electrical and locomotor between individuals of weakly electric fish. We confronted single individuals of Mormyrus rume proboscirostris with a mobile dummy fish designed to attract fish from a shelter and recruit them into an open area by emitting electrical playbacks of natural discharge sequences. We found that fish were reliably recruited by the mobile dummy if it emitted electrical signals and followed it largely independently of the presented playback patterns. While following the dummy, fish interacted with it spatially by displaying stereotypical motor patterns, as well as electrically, e.g. through discharge regularizations and by synchronizing their own discharge activity to the playback. However, the overall emission frequencies of the dummy were not adopted by the following fish. Instead, social signals based on different temporal patterns were emitted depending on the type of playback. In particular, double pulses were displayed in response to electrical signaling of the dummy and their expression was positively correlated with an animals' rank in the dominance hierarchy. Based on additional analysis of swimming trajectories and stereotypical locomotor behavior patterns, we conclude that the reception

  2. The fate of radionuclides in the body

    International Nuclear Information System (INIS)

    Fritsch, P.; Le Gall, B.

    2003-01-01

    Depending on the way in which a radionuclide arrives in the body, its fate and the possible effects of the contamination can range widely. To evaluate fully and realistically the consequences of a possible internal contamination by a radionuclide it is therefore most important to study the way in which it is transported in the body, whether and how it binds to different tissues and organs, and by what means it is likely to be eliminated. (authors)

  3. Internal radiation dosimetry in radionuclide therapy

    International Nuclear Information System (INIS)

    Kim, Kyeong Min; Lim, Sang Moo

    2006-01-01

    Radionuclide therapy has been continued for treatment of incurable diseases for past decades. Relevant evaluation of absorbed dose in radionuclide therapy in important to predict treatment output and essential for making treatment planning to prevent unexpected radiation toxicity. Many scientists in the field related with nuclear medicine have made effort to evolve concept and technique for internal radiation dosimetry. In this review, basic concept of internal radiation dosimetry if described and recent progress in method for dosimetry is introduced

  4. Livermore Accelerator Source for Radionuclide Science (LASRS)

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, Scott [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Bleuel, Darren [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Johnson, Micah [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Rusnak, Brian [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Soltz, Ron [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Tonchev, Anton [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2016-05-05

    The Livermore Accelerator Source for Radionuclide Science (LASRS) will generate intense photon and neutron beams to address important gaps in the study of radionuclide science that directly impact Stockpile Stewardship, Nuclear Forensics, and Nuclear Material Detection. The co-location of MeV-scale neutral and photon sources with radiochemical analytics provides a unique facility to meet current and future challenges in nuclear security and nuclear science.

  5. The uptake of radionuclides by plants

    International Nuclear Information System (INIS)

    Cawse, P.A.; Turner, G.S.

    1982-02-01

    A review of the literature, since 1970, on the research into the uptake of radionuclides by plants, with references to earlier soil and plant studies on the fate of nuclear weapons fallout. Experimental data on the uptake of plutonium isotopes, americium 241, cesium 137, radium 226, curium 244 and neptunium 237 and details of the chemical form of the radionuclide, soil type and plant growth period are tabulated. (U.K.)

  6. Artificial life and life artificialization in Tron

    Directory of Open Access Journals (Sweden)

    Carolina Dantas Figueiredo

    2012-12-01

    Full Text Available Cinema constantly shows the struggle between the men and artificial intelligences. Fiction, and more specifically fiction films, lends itself to explore possibilities asking “what if?”. “What if”, in this case, is related to the eventual rebellion of artificial intelligences, theme explored in the movies Tron (1982 and Tron Legacy (2010 trat portray the conflict between programs and users. The present paper examines these films, observing particularly the possibility programs empowering. Finally, is briefly mentioned the concept of cyborg as a possibility of response to human concerns.

  7. Cesium-137 and natural radionuclides in soils from southern Brazil and soils and others environmental samples from Antarctic

    International Nuclear Information System (INIS)

    Schuch, L.A.

    1993-04-01

    This work presents a study of environmental artificial and natural radioactivity levels in soil samples from the Southern Brazil and in soils and other environmental samples form Antarctica. Artificial radioactivity was determined by measuring Cs-137 which is a 30.1 year half-life man-made radionuclide produced in the past by atmospheric tests of nuclear weapons. Natural radioactivity was determined by measuring some radionuclides belonging to Th-232 and U-238 natural radioactive families, and of K-40 concentrations. Several types of soils from Southern Brazil; and soil samples, marine sediments, lichens, mosses and algae collected at King George and other nearby islands (South Shetland Archipelago, Antarctica) were analyzed. A gamma-ray spectrometer was used to measure radioactivity levels of the collected samples and its overall characteristics are analyzed in this work. (author)

  8. Development of long-lived radionuclide partitioning technology

    International Nuclear Information System (INIS)

    Lee, Eil Hee; Kwon, S. G.; Yang, H. B.

    2001-04-01

    This project was aimed at the development of an optimal process that could get recovery yields of 99% for Am and Np and 90% for Tc from a simulated radioactive waste and the improvements of unit processes. The performed works are summarized, as follows. 1) The design and the establishment of a laboratory-scale partitioning process were accomplished, and the interfacial conditions between each unit process were determined. An optimal flow diagram for long-lived radionuclide partitioning process was suggested. 2) In improvements of unit processes, a) Behaviors of the co-extraction and sequential separation for residual U, Np and Tc(/Re) by chemical and electrochemical methods were examined. b) Conditions for co-extraction of Am/RE, and selective stripping of Am with metal containing extractant and a mixed extractant were decided. c) Characteristics of adsorption and elution by ion exchange chromatography and extraction chromatography methods were analysed. d) The simulation codes for long-lived radionuclide partitioning were gathered. and reaction equations were numerically formulated. 3) An existing γ-lead cell was modified the α-γ cells for treatment of long-lived radioactive materials. 4) As the applications of new separation technologies, a) Behaviors of photo reductive precipitation for Am/RE were investigated, b) Conditions for selective extraction and stripping of Am with pyridine series extractants were established. All results will be used as the fundamental data for establishment of partitioning process and radiochemical test of long-lived radionuclides recovery technology to be performed in the next stage

  9. Natural radionuclides in effluents release by a deactivated uranium mine

    Energy Technology Data Exchange (ETDEWEB)

    Pereira, Wagner S.; Kelecom, Alphonse; Silva, Ademir X.; Lopes, José M.; Pinto, Carlos E.C.; Py Júnior, Delcy A.; Antunes, Marcos M., E-mail: pereiraws@gmail.com, E-mail: caerjbr@gmail.com, E-mail: wspereira@inb.gov.br, E-mail: delcy@inb.gov.br, E-mail: Antunes@inb.gov.br, E-mail: lararapls@hotmail.com, E-mail: Ademir@nuclear.ufrj.br, E-mail: marqueslopes@yahoo.com.br [Universidade Veiga de Almeida (UVA), Rio de Janeiro, RJ (Brazil); Indústrias Nucleares do Brasil (COMAP.N/FCN/INB), Resende RJ (Brazil). Fábrica de Combustível Nuclear. Coordenação de Meio Ambiente e Proteção Radiológica Ambiental; Universidade Federal Fluminense (LARARA-PLS/UFF), Niterói, RJ (Brazil). Laboratório de Radiobiologia e Radiometria; Coordenacao de Pos-Graduacao e Pesquisa de Engenharia (COPPE/UFRJ), Rio de Janeiro, RJ (Brazil). Programa de Engenharia Nuclear

    2017-07-01

    The Ore Treatment Unit (OTU) is a mine and deactivated uranium plant in the city of Caldas, Minas Gerais, Brazil. This facility possesses three points of release of liquid effluents containing radionuclides: point 014, 025 and 076. At these points, the values of activity concentrations (AC) of the radionuclides U{sub nat}, {sup 226}Ra, {sup 210}Pb, {sup 232}Th and {sup 228}Ra were analyzed in 2012. The evaluation of point 014 by univariate statistics pointed four groups. [U{sub nat} > {sup 228}Ra > ({sup 226}Ra = {sup 210}Pb) >{sup 232}Th]. The multivariate statistics separated the radionuclides into two groups: [(U{sub nat} and {sup 232}Th) and ({sup 226}Ra, {sup 228}Ra and {sup 210}Pb)]. At point 025, the univariate statistics described three groups: [Un{sub at} > ({sup 228}Ra = {sup 210}Pb) > ({sup 226}Ra = {sup 232}Th)] and the multivariate analysis also described three but different groups: [(U{sub nat} and {sup 228}Ra), ({sup 226}Ra and {sup 210}Pb) and {sup 232}Th]. In turn, point 076 showed another behavior. The univariate analysis showed only two groups: [(U{sub nat}) > ({sup 226}Ra, {sup 228}Ra, {sup 210}Pb, {sup 232}Th)]. Differently, the multivariate statistics defined three groups: [(U{sub nat} and {sup 232}Th), ({sup 226}Ra and {sup 228}Ra) and {sup 210}Pb].Thus, statistical analysis showed that each point has releases of effluents with different characteristics. Both the behaviors of releases, based on multivariate statistics, and of the AC magnitudes, based on the univariate statistics, are different between the points. The only common features were the greater magnitude of uranium and the smaller magnitude of thorium. (author)

  10. Review of radionuclide treatment for neuroendocrine tumors

    International Nuclear Information System (INIS)

    Jeong, Hwan Jeong

    2006-01-01

    Neuroendocrine tumors (NETs) consist of a heterogeneous group of tumors that are uptake neuroamine and/or specific receptors, such as somatostatin receptors, which can play important roles of the localization and treatment of these tumors. When considering therapy with radionuclides, the best radioligand should be carefully investigated. 131 I-MIBG and beta-particle emitter labeled somatostatin analogs are well established radionuclide therapy modalities for NETs. 111 In, 90 Y and 177 Lu radiolabelled somatostatin analogues have been used for treatment of NETs. Further, radionuclide therapy modalities, for example, radioimmunotherapy, radiolabeled peptides such as minigastrin are currently under development and in different phases of clinical investigation. For all radionuclides used for therapy, long-tem and survival statistics are not yet available and only partial tumour responses have been obtained using 131 I-MIBG and 111 In-octreotide. Experimental results using 90 Y-DOTA-lanreotide as well as 90 Y-DOTA-D -Phe1-Tyr 3 -octreotide and/or 177 Lu-DOTA-Tyr 3 -octreotate have indicated the possible clinical potential of radionuclides receptor-targeted radiotherapy. It may be hoped that the efficacy of radionuclide therapy will be improved by co-administration of chemotherapeutic drugs whose antitumoral properties may be synergistic with that of irradiation

  11. Radionuclide therapy practice and facilities in Europe

    International Nuclear Information System (INIS)

    Hoefnagel, C.A.; Clarke, S.E.M.; Fischer, M.; Chatal, J.F.; Lewington, V.J.; Nilsson, S.; Troncone, L.; Vieira, M.R.

    1999-01-01

    Using a questionnaire the EANM Task Group Radionuclide Therapy in 1993 collected data on the current practice of radionuclide therapy in European countries. Subsequently, at the request of the EANM Executive Committee, the EANM Radionuclide Therapy Committee has made an inventory of the distribution of facilities for radionuclide therapy and undertaken an assessment of the total number of patients treated throughout Europe and of the types of treatment provides, with the aim of supporting the development of policy to adjust the available capacity to the needs by the year 2000. For this purpose, a second, more detailed questionnaire was sent out the members and national advisors of the Committee (see below), who gathered the data for each country that was a member of the EANM at the time. It is concluded that a wide bariation in therapy practice exists across Europe, particularly in the utilisation of radionuclide therapy, the requirement and availability of proper isolation facilities and the background training of those undertaking therapy. More uniform guidelines and legislation are required, although changes in legislation may have a significant impact in some countries. Although there is wide variation in the therapies used in each country, one the whole it appears that there is an underutilisation of nuclear medicine as a therapeutic modality. A rapidly increasing role may be expected, in particular for oncological indications requiring high-dose radionuclide treatment. Therefore there is an urgent need for a greater number of isolation beds in dedicated centers throughout Europe

  12. Radionuclide Air Emissions Report for 2012

    Energy Technology Data Exchange (ETDEWEB)

    Wahl, Linnea [Ernest Orlando Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States)

    2013-05-01

    Berkeley Lab operates facilities where radionuclides are produced, handled, store d, and potentially emitted . These facilities are subject to the EPA radioactive air emission regulations in 40 CFR 61, Subpart H (EPA 1989a). Radionuclides may be emitted from stacks or vents on buildings where radionuclide production or use is authorized or they may be emitted as diffuse sources. In 2012, all Berkeley Lab sources were minor sources of radionuclides (sources resulting in a potential dose of less than 0.1 mrem/yr [0.001 mSv/yr]) . These minor sources include d about 140 stack sources and no diffuse sources . T here were no unplanned airborne radionuclide emissions from Berkeley Lab operations . Emissions from minor sources were measured by sampling or monitoring or were calculated based on quantities used, received for use, or produced during the year. Using measured and calculated emissions, and building- specific and common parameters, Laboratory personnel applied the EPA -approved computer code s, CAP88-PC and COMPLY , to calculate doses to the maximally exposed individual (MEI) at any offsite point where there is a residence, school, business, or office. Because radionuclides are used at three noncontiguous locations (the main site, Berkeley West Bio center, and Joint BioEnergy Institute), three different MEIs were identified.

  13. Radionuclide therapy practice and facilities in Europe

    Energy Technology Data Exchange (ETDEWEB)

    Hoefnagel, C.A.; Clarke, S.E.M.; Fischer, M.; Chatal, J.F.; Lewington, V.J.; Nilsson, S.; Troncone, L.; Vieira, M.R.

    1999-03-01

    Using a questionnaire the EANM Task Group Radionuclide Therapy in 1993 collected data on the current practice of radionuclide therapy in European countries. Subsequently, at the request of the EANM Executive Committee, the EANM Radionuclide Therapy Committee has made an inventory of the distribution of facilities for radionuclide therapy and undertaken an assessment of the total number of patients treated throughout Europe and of the types of treatment provides, with the aim of supporting the development of policy to adjust the available capacity to the needs by the year 2000. For this purpose, a second, more detailed questionnaire was sent out the members and national advisors of the Committee (see below), who gathered the data for each country that was a member of the EANM at the time. It is concluded that a wide bariation in therapy practice exists across Europe, particularly in the utilisation of radionuclide therapy, the requirement and avilability of proper isolation facilities and the background training of those undertaking therapy. More uniform guidelines and legislation are required, although changes in legislation may have a significant impact in some countries. Although there is wide variation in the therapies used in each country, one the whole it appears that there is an underutilisation of nuclear medicine as a therapeutic modality. A rapidly increasing role may be expected, in particular for oncological indications requiring high-dose radionuclide treatment. Therefore there is an urgent need for a greater number of isolation beds in dedicated centers throughout Europe. With 8 tabs.

  14. Inventories of selected radionuclides in the oceans

    International Nuclear Information System (INIS)

    1988-10-01

    In March 1984 an ad hoc Review Committee composed of senior experts in the marine radioactivity field made recommendations that ''the Monaco Laboratory should be engaged in compiling and evaluating the input of radionuclides into the marine environment''. The Committee recommended that work should commence on selected radionuclides, viz., 14 C, caesium isotopes, plutonium isotopes, 210 Po and 210 Pb followed by 226 Ra. Depending on the radionuclides involved the assistance of competent experts from outside as well as inside the IAEA was sought. The present document is a product of the work carried out within the framework of the above-mentioned task and contains reports on 14 C, 90 Sr, 137 Cs, 238 Pu, 239+240 Pu, 210 Pb, 210 Po and 226 Ra. Although the estimation of the inventory in the marine environment and related input and output fluxes, is the same for all radionuclides concerned, different approaches were followed to achieve this objective. These approaches depended on the geochemical characteristics of the radionuclides and the availability of data for different times and locations. For regions where data were lacking, extrapolation on the basis of specific assumptions has often been necessary. As the work was initiated during the pre-Chernobyl period, the radionuclides derived from the Chernobyl incident were not, in general, considered. Since the work for preparing the forthcoming report of the UNSCEAR is scheduled to be completed by 1991, it is hoped that the information contained in this volume will be beneficial. Refs, figs and tabs

  15. Solubility limits on radionuclide dissolution

    Energy Technology Data Exchange (ETDEWEB)

    Kerrisk, J.F.

    1984-12-31

    This paper examines the effects of solubility in limiting dissolution rates of a number of important radionuclides from spent fuel and high-level waste. Two simple dissolution models were used for calculations that would be characteristics of a Yucca Mountain repository. A saturation-limited dissolution model, in which the water flowing through the repository is assumed to be saturated with each waste element, is very conservative in that it overestimates dissolution rates. A diffusion-limited dissolution model, in which element-dissolution rates are limited by diffusion of waste elements into water flowing past the waste, is more realistic, but it is subject to some uncertainty at this time. Dissolution rates of some elements (Pu, Am, Sn, Th, Zr, Sm) are always limited by solubility. Dissolution rates of other elements (Cs, Tc, Np, Sr, C, I) are never solubility limited; their release would be limited by dissolution of the bulk waste form. Still other elements (U, Cm, Ni, Ra) show solubility-limited dissolution under some conditions. 9 references, 3 tables.

  16. Radionuclide scintigraphy of bacterial nephritis

    Energy Technology Data Exchange (ETDEWEB)

    Conway, J.J.; Weiss, S.C.; Shkolnik, A.; Yogev, R.; Firlit, C.; Traisman, E.S.

    1984-01-01

    Pyelonephritis is a leading cause of renal failure and is expected to cost as much as three billion dollars in 1984. The diagnosis of urinary tract infection is usually not difficult. However, localization of the infection within the renal parenchyma as opposed to the collecting system is much more difficult. Flank pain, fever, bacteiuria and evidence of parenchymal involvement by intravenous urography may be absent or unrecognized particularly in the infant. Ultrasound and Nuclear Medicine are advocated as better methods to define parenchymal involvement. Such definition is important in the consideration of treatment since parenchymal involvement of the kidney carries a much more ominous potential outcome than infection restricted to within the collecting system. 38 children with a clinical diagnosis of urinary tract infection were studied. 26 of the patients demonstrated abnormal renal parenchymal findings with Gallium-67 Citrate or Tc-99m Glucoheptonate scintigraphy. Intravenous urography was notably ineffective with only 5 of the 20 interpreted as abnormal due to parenchymal disease or decreased function. 11 were entirely normal while only 5 demonstrated scars or hydronephrosis. Only 10 of 17 patients demonstrated intranvesicoureteral reflux on x-ray or nuclear cystography. Ultrasound depicted 6 of 20 patients as having parenchymal abnormalities. Seven were normal. Nonspecific findings such as dilitation of the renal pelvis or renal enlargement was noted in 11 of the 20 patients. Radionuclide Scintigraphy is the most efficacious modality to detect since acute bacterial nephritis.

  17. Radionuclides sorption in clay soils

    International Nuclear Information System (INIS)

    Siraky, G.; Lewis, C.; Hamlat, S.; Nollmann, C.E.

    1987-01-01

    The sorption behaviour of clay soils is examined through a parametric study of the distribution coefficient (Kd) for the radionuclides of interest, Cs and Sr. This work is a preliminary stage of the migration studies of these nuclides in a porous medium (ground of Ezeiza, Argentina) and the evaluation of radiologic impact of the removal of low and intermediate activity wastes in shallow trenches. The determination of Kd is performed by a static technique or batch. The phases are separated by centrifugation at 20000 g during 1 hour. The activity of supernatant solution of Cs-137 and Sr-85 is measured in a detecting system of I Na(Tl) well-type. Two types of parameters were changed: a) those related to the determination method: phase separation (centrifugation vs. centrifugation plus filtration); equilibrium period, ratio solid/liquid; b) those related to the geochemical system: pH of contact solution, carrier concentration, competitive ions, ionic strength, desorption. It was observed that the modification of parameters in the Kd-measurement does not change the order of magnitude of results. (Author)

  18. Radionuclide transport in fractured media

    International Nuclear Information System (INIS)

    Williams, M.M.R.

    1993-01-01

    Until recently, the classical advective-dispersive transport equation was considered to be an adequate model for describing the motion of a solute (e.g. radionuclides) in porous and fractured media. In this model, the dispersion coefficient is either obtained from a microscopic model of the porous medium or by carefully controlled experiments. As a result of such experiments, a large body of data has been accumulated on the dispersivity. Detailed examination of these data has resulted in a curious phenomenon being discovered; namely, that the longitudinal dispersion length is 'scale-dependent'. That is to say the value deduced depends on the 'size' of the experiment, i.e. on the distance over which measurements are made. Several interesting attempts have been made to develop theories which explain this phenomenon, all based on treating the velocity of the water in the porous medium as a spatially random variable, but retaining the advective-dispersive balance equation. In this work we present an entirely new approach to the problem of solute transport in fractured media based upon an analogy with neutron transport. The new method has several advantages over the previous theories and these will be explained below. Results from the new theory are in agreement with experimental trends and do not require any further adjustment to explain the scale-dependent effect

  19. Radionuclides in forest biogeocenose elements

    International Nuclear Information System (INIS)

    Bulavik, I.M.; Zhuchenko, T.A.

    1992-01-01

    In 1991 year investigations are made on a studying of the radionuclide distribution (CS-137 and Sr-90) through the main forest biogeocenose elements (a litter a mineral soil layer, overground trees parts) on 5 experimental objects of Gomel' region with a various contamination. Radiation characters of the objects are done. As compared with 1989 year cesium and strontium migration from tress into the litter and from the litter to the soil is shown. In the litter and upper soil layer (5 m) contents of Cs-137 and Sr-90 are 95 and 80% accordingly. The Sr-90 concentration in the wood and the isotope concentration change through yearly layers (1986-1991 years) are studied. Wood layers formed to the accident have a lesser cesium concentration, especially in the oax-tree. The highest Cs and Se translocation, into the wood is noted in the pine the lesse one in the oax-tree. Among all elements of the biogeocenose the highest Cs-137 concentration the litter has and then one-year-old shoots, needles, lives, the bark and the wood go on. Even on the sixth year after the accident Cs concentration in the wood was 20-30 times less, than the one in needes and one-year-old shoot of this year. 4 refs.; 5 tabs

  20. Quo vadis radionuclide ventriclography (RNV)?

    International Nuclear Information System (INIS)

    Hoer, G.; Hertel, A.; Diehl, M.

    1999-01-01

    Unjustifiably radionuclide ventriculography (RNV) lost some of its importance with the advance of stress-echocardiography. This editorial aims at reviewing the advantages and disadvantages of both procedures, pointing to the ability of standardized and reproducible quantified global and regional (sectorial) multiparametric analysis, as compared to the qualitative evaluation of global left ventricular function and regional wall motion abnormalities, utilizing stress-echo. Based on a questionnaire sent to German centers the sequence of clinical application of RNV runs like this: Cardiomyopathy, cardiotoxicity-testing, coronary artery disease (CAD) - prognosis, remodeling, risk stratification - PTCA - success and failure - valve disease (chronic aortic insufficiency), cardiac transplantation (observation of progressive vasulopathies) and pharmaceutical testing. Differences in comparison to the guidelines of task force groups in USA are opposed where a consensus conference is still missing in Germany. Final outlook is given on combining PET-derived ejection fraction together with ECG-gated PET (GAPET) for quantification of function, regional perfusion (ischemia) and viable myocardium (hibernating myocardium). Control of successful revascularization by modern angioplasty techniques such as stent implantation, laser angioplasty today is primarily subject to echocardiography, where it is to be considered that the sensitivity of stress-echo is equivalent to nuclear medicine procedures in multivessel disease but inferior to nuclear medicine in single vessel disease and small vessel disease (with normal coronary angiography). (orig.) [de