WorldWideScience

Sample records for artificial radioactive aerosols

  1. Radioactive aerosols

    International Nuclear Information System (INIS)

    Chamberlain, A.C.

    1991-01-01

    Radon. Fission product aerosols. Radioiodine. Tritium. Plutonium. Mass transfer of radioactive vapours and aerosols. Studies with radioactive particles and human subjects. Index. This paper explores the environmental and health aspects of radioactive aerosols. Covers radioactive nuclides of potential concern to public health and applications to the study of boundary layer transport. Contains bibliographic references. Suitable for environmental chemistry collections in academic and research libraries

  2. The electrical charging of inactive aerosols in high ionised atmosphere, the electrical charging of artificial beta radioactive aerosols; Le processus de charge electrique: des aerosols non radioactifs en milieu fortement ionise, des aerosols radioactifs artificiels emetteurs beta

    Energy Technology Data Exchange (ETDEWEB)

    Gensdarmes, F

    2000-07-01

    The electrical properties of aerosols greatly influence their transport and deposition in a containment. In a bipolar ionic atmosphere, a neutral electric charge on aerosols is commonly assumed. However, many studies report a different charge distribution in some situations, like highly ionised atmosphere or in the case of radioactive aerosols. Such situations could arise from a hypothetical accident in a nuclear power plant. Within the framework of safety studies which are carried out at IPSN, our aims were the study of electrical properties of aerosols in highly ionised atmosphere, and the study of artificial radioactive aerosols, in order to suggest experimental validation of available theories. For this purpose, we designed an experimental device that allows us to measure non-radioactive aerosol charge distribution under high gamma irradiation, up to 10{sup 4} Gy/h. With our experimental device we also studied the properties of small ions in the medium. Our results show a variation of the charge distribution in highly ionised atmosphere. The charge increases with the dose of gamma ray. We have related this variation with the one of the small ions in the gases, according to theoretical prediction. However, the model overestimates slightly our experimental results. In the case of the radioactive aerosols, we have designed an original experimental device, which allows us to study the charge distribution of a {sup 137}Cs aerosol. Our results show that the electric charging of such aerosols is strongly dependent on evolution parameters in a containment. So, our results underline a great enhancement of self-charging of particles which are sampled in a confined medium. Our results are qualitatively in agreement with the theoretical model; nevertheless the latter underestimates appreciably the self-charging, owing to the fact that wall effects are not taken into account. (author)

  3. Development of α and/or β activity aerosol instrumentation

    International Nuclear Information System (INIS)

    Lu Zhengyong; Li Aiwu; Gou Quanlu

    1996-01-01

    A radioactive aerosol instrumentation is developed recently for measuring the α and/or β activity of artificial radioactivity aerosols which are produced in nuclear facilities. The instrumentation has the function discriminating natural radioactivity aerosols resulted from radon and thoron daughters, and it is enabled in time and without delay to measure α and β artificial activity collected with a filter by pumping aerosols through this filter. The energy discrimination and compensation method is used for eliminating the influence of natural αradioactivity aerosols. To minimize the influence of natural β-radioactivity aerosols, the method measuring the ratio α/β of natural aerosols is also used in the instrument. The improved methods eliminating the influence of natural background α and β aerosols are used so that both α and β artificial activities in aerosol filter samples can be monitored simultaneously. The instrumentation is appropriate for monitoring α and/or β artificial radioactive aerosols

  4. Radioactive aerosols. [In Russian

    Energy Technology Data Exchange (ETDEWEB)

    Natanson, G L

    1956-01-01

    Tabulations are given presenting various published data on safe atmospheric concentrations of various radioactive and non-radioactive aerosols. Methods of determination of active aerosol concentrations and dispersion as well as the technical applications of labeled aerosols are discussed. The effect of atomic explosions are analyzed considering the nominal atomic bomb based on /sup 235/U and /sup 232/Pu equivalent to 20,000 tons of TNT.

  5. Connection of comparator circuit for pseudocoincidence counting of radioactive aerosols

    International Nuclear Information System (INIS)

    Fukatko, T.; Hajek, P.; Vidra, M.

    1985-01-01

    A block diagram is presented of the radioactive aerosol measuring instrument. The first counter records electric pulses corresponding to gross alpha activity and the second indicates pseudocoincidences derived from natural radioactivity. Data from the counters are converted to analog voltages which in the comparator circuit are compared such that the mean value of the output voltage is zero insofar as artificial radioactivity is not present on the filter. The designed connection of the comparator circuit allows the permanent adjustment of the whole measuring equipment to maximum sensitivity. (E.S.)

  6. Results of concentration measurements of artificial radioactive aerosols in the lower atmosphere; Resultats des mesures de concentration, dans la basse atmosphere, des aerosols radioactifs artificiels

    Energy Technology Data Exchange (ETDEWEB)

    Ardouin, B; Jehanno, C; Labeyrie, J; Lambert, G; Tanaevsky, O; Vassy, E [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1963-07-01

    This report gives the results of the measurements of artificial gross-{beta}-radioactivity in aerosols in the lower atmosphere; these measurements have been made by the Electronic Physics Service of the Electronic Department, and by the Atmospheric Physics Laboratory of the Paris Science Faculty. The measurements were begun in September 1956 and were continued in an increasing number of stations both in France and in the rest of the world. The present report deals with the period up to the end of august 1961, that is up to the end of the nuclear moratorium. After recalling the constitution and the properties of radioactive aerosols present in the atmosphere, the authors describe the measurement methods, estimate their accuracy and discuss various aspects of the results. (authors) [French] Ce rapport contient les resultats des mesures de radioactivite {beta} globale d'origine artificielle des aerosols dans la basse atmosphere, effectuees conjointement par le Service d'Electronique Physique du Departement d'Electronique et le Laboratoire de Physique de l'Atmosphere de la Faculte des Sciences de Paris. Les mesures ont commence en septembre 1956 et ont ete poursuivies dans un nombre croissant de stations, tant en France que dans le reste du monde. Le present rapport s'arrete a la fin aout 1961, c'est-a-dire au moment de la reprise des essais nucleaires. Apres avoir rappele la constitution et les proprietes des aerosols radioactifs presents dans l'atmosphere, les auteurs indiquent les methodes de mesure utilisees, evaluent leur precision et discutent les differents aspects des resultats de leurs mesures. (auteurs)

  7. Study of the behaviour of artificial radioactive aerosols. Applications to some problems of atmospheric circulation (1963)

    International Nuclear Information System (INIS)

    Lambert, G.

    1963-11-01

    The aim of this work, consists in the examination of the behaviour of radioactive aerosols produced in the atmosphere by nuclear explosions, in order to deduce the most general laws governing atmospheric circulation and diffusion. After having given a general table of the radioactive aerosols present the authors consider the validity and the precision of the measurement methods and the concentration of the aerosols at ground level and in the upper atmosphere, as well as their deposition on the ground. The existence is thus demonstrated of a tropospheric equatorial barrier and of discontinuous and seasonal aspects of stratosphere-troposphere transfers. The role is shown of precipitations and dry auto-filtration in the lower atmosphere cleaning processes. This work makes it possible to describe the general behaviour of dust from the stratosphere, and to improve the total radioactive contamination of the globe. (author) [fr

  8. Radioactive content in aerosols and rainwater

    International Nuclear Information System (INIS)

    Rodriguez Perestelo, N.; Lopez Perez, M.; Rodriguez, S.; Duarte, X.; Catalan, A.; Fernandez de Aldecoa, J. C.; Hernandez, J.

    2013-01-01

    The environmental radiological characterization of a place requires knowledge of the radioactive contents of its components, such as air (aerosol), rain, soil, etc ... Inhalation of radioactive aerosols in the air remains the main component of the total dose to the world population. This work focuses on its determination. (Author)

  9. The effect of radioactive aerosols on fog formation

    International Nuclear Information System (INIS)

    Ali, G.; Khan, E.U.; Ali, N.; Khan, H.A.; Waheed, A.

    2011-01-01

    This research study has been carried out to explore the dependence of fog formation on radioactive aerosols. The aerosols containing radioactive nuclides are called radioactive aerosols. A large number of radioactive nuclides are present in the atmosphere among which the two most important nuclides, 7Be and 210Pb are considered here in this study. Results for Activity Concentrations of these radio-nuclides in air samples in clear and foggy conditions were comparatively analyzed. About 19% increase in Activity concentration for 210Pb and about 23% increase in Activity Concentration for 7Be was recorded during fog as compared to clear conditions. This increase in Activity Concentration during fog indicates that the presence of aerosols laden with these radio-nuclides is also one of the so many factors responsible for fog formation

  10. Adsorption of radioactive ions on carnauba-wax aerosols

    Energy Technology Data Exchange (ETDEWEB)

    Paul, A.; Keyser, U. [Physikalisch-Technische Bundesanstalt, Braunschweig (Germany)

    1998-08-01

    A new method based on parallel aerosol size spectrometry and {gamma}-spectrometry is introduced for the measurement of short-lived radioactive ions, fission products or super-heavy elements produced at accelerators. Furthermore a new aerosol generator is presented.The possibility of controlling and changing the aerosol size distribution in the helium aerosol jet produced by the aerosol generator allows the process of the adsorption and transport of radioactive ions on aerosols to be examined for the first time. This is due to the fact that the distribution is surveyed on-line using a negligible part of its total volume and parallel to the transporting flow. The radioactivity of the transported ions is measured by a germanium detector in offline position. In principle, both an on- or offline position with narrow multi-detector geometry (e.g. {beta}{gamma}{gamma}) is possible. (orig.) With 8 figs., 14 refs.

  11. Design of automatic control and measurement software for radioactive aerosol continuity monitor

    International Nuclear Information System (INIS)

    Mao Yong; Li Aiwu

    1997-01-01

    The radioactive aerosol continuity measurement is very important for the development of nuclear industry, and it is the major method to measure and find out the leakage of radioactive material. Radioactive aerosol continuity monitor is the advanced method for the radioactive aerosol continuity measurement. With the development of nuclear industry and nuclear power station, it is necessary to design and automatic continuity measurement device. Because of this reason, the authors developed the first unit of radioactive aerosol continuity monitor and adopted the ministry appraisal. The design idea and method of automatic control and measurement for radioactive aerosol continuity monitor are discussed

  12. Radioactive Aerosol Size Distribution Measured in Nuclear Workplaces

    International Nuclear Information System (INIS)

    Kravchik, T.; Oved, S.; German, U.

    2002-01-01

    Inhalation is the main route for internal exposure of workers to radioactive aerosols in the nuclear industry.Aerosol's size distribution and in particular its activity median aerodynamic diameter (AMAD)is important for determining the fractional deposition of inhaled particles in the respiratory tract and the resulting doses. Respiratory tract models have been published by the International Commission on radiological Protection (ICRP).The former model has recommended a default AMAD of 1 micron for the calculation of dose coefficients for workers in the nuclear industry [1].The recent model recommends a 5 microns default diameter for occupational exposure which is considered to be more representative of workplace aerosols [2]. Several researches on radioactive aerosol's size distribution in nuclear workplaces has supported this recommendation [3,4].This paper presents the results of radioactive aerosols size distribution measurements taken at several workplaces of the uranium production process

  13. The measurement of the radioactive aerosol diameter by position sensitive detectors, 3

    International Nuclear Information System (INIS)

    Murakami, Hiroyuki; Nakamoto, Atsushi; Kanamori, Masashi; Seki, Akio.

    1981-10-01

    The measurement of the diameter of radioactive aerosol, in particular plutonium aerosol, is very important for the internal dose estimation. Determination of the diameter of radioactive aerosol is performed by using the position sensitive detectors. Position sensitive semiconductor detectors and Scintillation detectors with IIT tube are used as the position sensitive detector. The filter paper with the radioactive aerosols is contacted to the PSD which is connected to the data processor so that the diameter of the aerosol is calculated from the measured radioactivity. (author)

  14. Virtual cascade impactors for the collection of radioactive atmospheric aerosols

    International Nuclear Information System (INIS)

    Berner, A.

    1988-01-01

    Starting from impaction theory, the properties of virtual impaction stages are discussed and compared to classical impactors. Virtual impaction stages offer the benefit of sampling coarse particles without bouncing and reentrainment, but turbulent mixing affects the performance of virtual stages. Future research should concentrate on special configurations for reducing the effects of turbulent mixing. Virtual impaction stages for sampling radioactive aerosols are to be designed in regard of the analytical requirements, the purpose of the measurements, and the aerosol. Therefore, the aerosol components expected in radioactive aerosols are discussed on the background of the multimodal model, which relates the size distribution to the genesis and the history of the aerosol. Reference is made to recent data of the radioactive atmospheric aerosol

  15. Radioactive content in aerosols and rainwater; Contenido radiactivo en aerosoles y agua de lluvia

    Energy Technology Data Exchange (ETDEWEB)

    Rodriguez Perestelo, N.; Lopez Perez, M.; Rodriguez, S.; Duarte, X.; Catalan, A.; Fernandez de Aldecoa, J. C.; Hernandez, J.

    2013-07-01

    The environmental radiological characterization of a place requires knowledge of the radioactive contents of its components, such as air (aerosol), rain, soil, etc ... Inhalation of radioactive aerosols in the air remains the main component of the total dose to the world population. This work focuses on its determination. (Author)

  16. Particle size of radioactive aerosols generated during machine operation in high-energy proton accelerators

    International Nuclear Information System (INIS)

    Oki, Yuichi; Kanda, Yukio; Kondo, Kenjiro; Endo, Akira

    2000-01-01

    In high-energy accelerators, non-radioactive aerosols are abundantly generated due to high radiation doses during machine operation. Under such a condition, radioactive atoms, which are produced through various nuclear reactions in the air of accelerator tunnels, form radioactive aerosols. These aerosols might be inhaled by workers who enter the tunnel just after the beam stop. Their particle size is very important information for estimation of internal exposure doses. In this work, focusing on typical radionuclides such as 7 Be and 24 Na, their particle size distributions are studied. An aluminum chamber was placed in the EP2 beam line of the 12-GeV proton synchrotron at High Energy Accelerator Research Organization (KEK). Aerosol-free air was introduced to the chamber, and aerosols formed in the chamber were sampled during machine operation. A screen-type diffusion battery was employed in the aerosol-size analysis. Assuming that the aerosols have log-normal size distributions, their size distributions were obtained from the radioactivity concentrations at the entrance and exit of the diffusion battery. Radioactivity of the aerosols was measured with Ge detector system, and concentrations of non-radioactive aerosols were obtained using condensation particle counter (CPC). The aerosol size (radius) for 7 Be and 24 Na was found to be 0.01-0.04 μm, and was always larger than that for non-radioactive aerosols. The concentration of non-radioactive aerosols was found to be 10 6 - 10 7 particles/cm 3 . The size for radioactive aerosols was much smaller than ordinary atmospheric aerosols. Internal doses due to inhalation of the radioactive aerosols were estimated, based on the respiratory tract model of ICRP Pub. 66. (author)

  17. The continuous monitoring of the artificial beta aerosol activity by measuring the alpha and beta activity in aerosol simultaneously

    International Nuclear Information System (INIS)

    Hayakawa, Hironobu; Oonishi, Masaki; Matsuura, Hiroyuki

    1990-01-01

    We have constructed the system to monitor the artificial beta aerosol activity around the nuclear power plants continuously in real time. The smaller releases of artificial radionuclides from the nuclear power plants can be lost in the fluctuations of the natural background of the beta aerosol activity, when only the beta activity of the aerosol is measured. This method to discriminate the artificial and the natural beta activity of the aerosol is based on the fact that the ratio of the natural alpha and beta activities of the aerosol is almost constant. The detection limit of this system is below 3 Bq/m 3 . (author)

  18. Artificial radioactivity in Lough Foyle

    International Nuclear Information System (INIS)

    Cunningham, J.D.; Ryan, T.P.; Lyons, S.; Smith, V.; McGarry, A.; Mitchell, P.I.; Leon Vintro, L.; Larmour, R.A.; Ledgerwood, F.K.

    1996-04-01

    The purpose of this study was to assess the extent to which the marine environment of Lough Foyle, situated on the north coast of Ireland, has been affected by artificial radioactivity released from Sellafield. Although traces of plutonium, americium and radiocaesium from Sellafield are detectable in Lough Foyle, the concentrations in various marine media are significantly lower than those found along the NE coast of Ireland and in the western Irish Sea. The minute quantities of artificial radioactivity found in Lough Foyle are of negligible radiological significance

  19. Principle of natural and artificial radioactive series equivalency

    International Nuclear Information System (INIS)

    Vasilyeva, A.N.; Starkov, O.V.

    2001-01-01

    In the present paper one approach used under development of radioactive waste management conception is under consideration. This approach is based on the principle of natural and artificial radioactive series radiotoxic equivalency. The radioactivity of natural and artificial radioactive series has been calculated for 10 9 - years period. The toxicity evaluation for natural and artificial series has also been made. The correlation between natural radioactive series and their predecessors - actinides produced in thermal and fast reactors - has been considered. It has been shown that systematized reactor series data had great scientific significance and the principle of differential calculation of radiotoxicity was necessary to realize long-lived radioactive waste and uranium and thorium ore radiotoxicity equivalency conception. The calculations show that the execution of equivalency principle is possible for uranium series (4n+2, 4n+1). It is a problem for thorium. series. This principle is impracticable for neptunium series. (author)

  20. An aerosole generator for production of radioactive aerosoles by evaporating uranium dioxide

    International Nuclear Information System (INIS)

    Pusch, W.M.

    1975-01-01

    In the Institut for Biology of the Austrian Research Center at Seibersdorf an experiment is running to study the behaviour of radioactive aerosoles in the organism of miniature swines after inhalation. In the work under discussion the aerosole generator of the equipment used for this inhalation experiments is described by means of which the aerosole-air mixtures are produced. The main part of this generator is a gas burner for evaporating irradiated UO 2 -pellets. (orig.) [de

  1. Some considerations about the natural atmospheric radioactive aerosol

    International Nuclear Information System (INIS)

    Renoux, A.; Madelaine, G.

    1985-01-01

    From experiments made in Brest by the use of a semi-automatic device for direct measurements of atmospheric radon (the double filter method), we obtained daily average values of Radon 222 concentration, and establish that the values obtained are completely different according to the wind direction. We establish that radioactive balance is never realized in the air between radon and its daughters RaA(Po218), RaB(Pb214) and RaC(Bi214); the state of radioactive balance strongly depends on wind direction. We also study the ionic state of the radioactive aerosol accruing from Radon 222. Using an experimental system consisting of absolute filters, diffusion batteries, cascade impactors and ions tubes, we establish the size distribution of natural radioactive aerosol. We thus show 40% of the natural atmospheric radioactivity is located on particles whose radii are inferior to 2 . 10-2 mm. A good agreement is provided between the theory and our experimental points

  2. Artificial radioactivity is fifty: 1934-1984

    International Nuclear Information System (INIS)

    Amaldi, E.; Biquard, P.; Goldstein, L.

    1984-01-01

    This book has been published on the occasion of the fiftieth anniversary celebration of the artificial radioactivity discovery; contributions from men who have been near the Joliot at the beginning of the artificial radioactivity, or whose work have been marked by this discovery are gathered in this book. Subjects have been choosed very freely by the authors; that explains their great diversity. The reader will find precious memories from direct witnesses of this great time; he will find also descriptions of the following works; he will even find audacious dreams on matter utilization possibilities, which may rise to-morrow [fr

  3. Study of the behaviour of artificial radioactive aerosols. Applications to some problems of atmospheric circulation (1963); Etude du comportement dcs aerosols radioactifs artificiels. Applications a quelques problemes de circulation atmospherique (1963)

    Energy Technology Data Exchange (ETDEWEB)

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

    1963-11-15

    The aim of this work, consists in the examination of the behaviour of radioactive aerosols produced in the atmosphere by nuclear explosions, in order to deduce the most general laws governing atmospheric circulation and diffusion. After having given a general table of the radioactive aerosols present the authors consider the validity and the precision of the measurement methods and the concentration of the aerosols at ground level and in the upper atmosphere, as well as their deposition on the ground. The existence is thus demonstrated of a tropospheric equatorial barrier and of discontinuous and seasonal aspects of stratosphere-troposphere transfers. The role is shown of precipitations and dry auto-filtration in the lower atmosphere cleaning processes. This work makes it possible to describe the general behaviour of dust from the stratosphere, and to improve the total radioactive contamination of the globe. (author) [French] L'objectif de ce travail consiste a examiner le comportement des aerosols radioactifs introduits dans l'atmosphere par les explosions nucleaires, pour en deduire les lois les plus generals de la circulation et diffusion atmospheriques. Apres avoir dresse un tableau d'ensemble des aerosols radioactifs presents, on examine la validite et la precision des methodes de mesure de leur concentration, au niveau du sol et en haute atmosphere, ainsi que de leur depot a la surface du sol. On met ainsi en evidence l'existence d'une barriere equatoriale tropospherique; l'aspect discontinu et saisonnier des transferts stratosphere-troposphere; le role des precipitations et de l'auto-filtration seche, dans les processus de nettoyage de la basse atmosphere. Ces etudes permettent de decrire le comportement general des poussieres d'origine stratospherique et d'ameliorer le bilan de la contamination radioactive du globe. (auteur)

  4. Study of the behaviour of artificial radioactive aerosols. Applications to some problems of atmospheric circulation (1963); Etude du comportement dcs aerosols radioactifs artificiels. Applications a quelques problemes de circulation atmospherique (1963)

    Energy Technology Data Exchange (ETDEWEB)

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

    1963-11-15

    The aim of this work, consists in the examination of the behaviour of radioactive aerosols produced in the atmosphere by nuclear explosions, in order to deduce the most general laws governing atmospheric circulation and diffusion. After having given a general table of the radioactive aerosols present the authors consider the validity and the precision of the measurement methods and the concentration of the aerosols at ground level and in the upper atmosphere, as well as their deposition on the ground. The existence is thus demonstrated of a tropospheric equatorial barrier and of discontinuous and seasonal aspects of stratosphere-troposphere transfers. The role is shown of precipitations and dry auto-filtration in the lower atmosphere cleaning processes. This work makes it possible to describe the general behaviour of dust from the stratosphere, and to improve the total radioactive contamination of the globe. (author) [French] L'objectif de ce travail consiste a examiner le comportement des aerosols radioactifs introduits dans l'atmosphere par les explosions nucleaires, pour en deduire les lois les plus generals de la circulation et diffusion atmospheriques. Apres avoir dresse un tableau d'ensemble des aerosols radioactifs presents, on examine la validite et la precision des methodes de mesure de leur concentration, au niveau du sol et en haute atmosphere, ainsi que de leur depot a la surface du sol. On met ainsi en evidence l'existence d'une barriere equatoriale tropospherique; l'aspect discontinu et saisonnier des transferts stratosphere-troposphere; le role des precipitations et de l'auto-filtration seche, dans les processus de nettoyage de la basse atmosphere. Ces etudes permettent de decrire le comportement general des poussieres d'origine stratospherique et d'ameliorer le bilan de la contamination radioactive du globe. (auteur)

  5. Size distributions of various radioactive aerosols in the ground-level atmosphere

    Energy Technology Data Exchange (ETDEWEB)

    Schumann, G.; Baust, E.

    1963-11-15

    To know the size spectra of radioactive aerosols is important for many reasons. Among others, the efficiency of measuring devices or biological processes, as for instance, retention in the lungs, depend on particle size.The work described deals mainly with two different components of radioactive aerosols in the atmosphere: the natural radon daughters and the fission products originating from nuclear test explosions.

  6. Aerosols radioactivity in the Bratislava atmosphere

    International Nuclear Information System (INIS)

    Sykora, I.; Chudy, M.; Durana, L.; Holy, K.; Meresova, J.

    2001-01-01

    In our laboratory we measured temporal variation of 7 Be concentration in the atmosphere in period 1977 -1994 years. The aerosols were collected through every month at Hydrometeorological Institute in Bratislava-Koliba, latitude 48 grad 10' and altitude 286 m above sea level. Since end of year 2000 we have started to continue monitoring radioactivity of atmosphere aerosols in new locality in Bratislava-Mlynska dolina. Beside 7 Be we measured also 210 Pb radionuclide aerosols concentration. For measured values 7 Be concentrations are considered corrections for decay radionuclide during the time of filters collection, time between end of collection and measurement and decay during the time of measurement. Obtained results for 7 Be concentrations in aerosols shows seasonal summer maximum, but for 210 Pb concentration in aerosols the seasonal variations are not evident. The temporal variations of this radionuclide which is originated in ground-level atmosphere are more sensitive on meteorological factors and can be also influenced by the industrial activity. For better understanding is needed long term monitoring. (authors)

  7. Electrically Driven Technologies for Radioactive Aerosol Abatement

    Energy Technology Data Exchange (ETDEWEB)

    David W. DePaoli; Ofodike A. Ezekoye; Costas Tsouris; Valmor F. de Almeida

    2003-01-28

    The purpose of this research project was to develop an improved understanding of how electriexecy driven processes, including electrocoalescence, acoustic agglomeration, and electric filtration, may be employed to efficiently treat problems caused by the formation of aerosols during DOE waste treatment operations. The production of aerosols during treatment and retrieval operations in radioactive waste tanks and during thermal treatment operations such as calcination presents a significant problem of cost, worker exposure, potential for release, and increased waste volume.

  8. Radiation protection instrumentation. Monitoring equipment. Radioactive aerosols in the environment

    International Nuclear Information System (INIS)

    1996-01-01

    This international standard applies to portable or installed equipment for continuous monitoring of radioactive aerosols in the environment in normal and emergency conditions. Monitoring involves continuous sampling and, where desirable, automatic start of sampling. The document applies particularly to the following assignments: (i) determination of the volume activity of radionuclides in the form of aerosols, either per time unit, along with its time changes, or in the integral form over a longer time period such as 24 h, and measurement of the volume sampled; (ii) triggering a warning alarm signal if the preset volume activity or time integral of the volume activity of aerosols has been exceeded. The document deals with radioactive aerosol monitor design, testing procedures, and documentation. Appended tables refer to the reference and normal testing conditions, tests in normal testing conditions, tests during changes of the affecting quantities, and tests of the air circuit. (P.A.)

  9. Charging and coagulation of water aerosols with negligible addition of high-radioactive droplets

    International Nuclear Information System (INIS)

    Vasil'eva, N.L.; Sedova, G.L.; Chernyj, L.T.

    1994-01-01

    The mechanics of electrocoagulation of water aerosols with negligible admixture of high-radioactive droplets is considered. A corresponding mathematical model has been worked out which describes the processes of ionization, electrification and coagulation of radioactive aerosols. Numerical studies are carried out for a series of typical aerosols on the time dependence of ion concentrations, charge and pure droplet concentrations, as well as the charge and radius of radioactive droplets. It is shown that coagulation can give rise to the growth of droplet radius from 5-10 μm up to 30-40 μm for a 10 4 s period f time, and therefore it can play a considerable role in the development of aerosols with droplet radius up to 20 μm when gravitational coagulation is insignificant

  10. Characterisation of radioactivity carrying aerosol in a mineral sand processing plant

    International Nuclear Information System (INIS)

    Jeffries, C.; Morawska, L.

    1998-01-01

    The techniques used to separate heavy mineral sand into mineral products produce a large amount of airborne particulate. Some of these particles are radioactive which is due to the thorium and, to a lesser extent, the uranium content of mineral sands. This study has investigated both the radioactive and respirable particle components (<10 μm) of the aerosol in a dry sand processing plant in Brisbane, Australia. A number of different measurement techniques have been used to characterise the aerosol in the plant. The mass, number and activity distributions have been determined by an eight stage cascade impactor and an Aerodynamic Particle Sizer (APS) with both instruments measuring 0.4 to 10 μm. Measurements of radon progeny concentrations and the extent of radon progeny attachment to micrometer sized particles has been investigated, as well as the extent of airborne thorium and uranium. The preliminary results from two sites are presented and comments are made on the relationship between total and radioactive aerosol

  11. Size measurement of radioactive aerosol particles in intense radiation fields using wire screens and imaging plates

    Energy Technology Data Exchange (ETDEWEB)

    Oki, Yuichi; Tanaka, Toru; Takamiya, Koichi; Ishi, Yoshihiro; UesugI, Tomonori; Kuriyama, Yasutoshi; Sakamoto, Masaaki; Ohtsuki, Tsutomu [Kyoto University Research Reactor Institute, Osaka (Japan); Nitta, Shinnosuke [Graduate School of Engineering, Kyoto University, Kyoto (Japan); Osada, Naoyuki [Advanced Science Research Center, Okayama University, Okayama (Japan)

    2016-09-15

    Very fine radiation-induced aerosol particles are produced in intense radiation fields, such as high-intensity accelerator rooms and containment vessels such as those in the Fukushima Daiichi nuclear power plant (FDNPP). Size measurement of the aerosol particles is very important for understanding the behavior of radioactive aerosols released in the FDNPP accident and radiation safety in high-energy accelerators. A combined technique using wire screens and imaging plates was developed for size measurement of fine radioactive aerosol particles smaller than 100 nm in diameter. This technique was applied to the radiation field of a proton accelerator room, in which radioactive atoms produced in air during machine operation are incorporated into radiation-induced aerosol particles. The size of 11C-bearing aerosol particles was analyzed using the wire screen technique in distinction from other positron emitters in combination with a radioactive decay analysis. The size distribution for 11C-bearing aerosol particles was found to be ca. 70 μm in geometric mean diameter. The size was similar to that for 7Be-bearing particles obtained by a Ge detector measurement, and was slightly larger than the number-based size distribution measured with a scanning mobility particle sizer. The particle size measuring method using wire screens and imaging plates was successfully applied to the fine aerosol particles produced in an intense radiation field of a proton accelerator. This technique is applicable to size measurement of radioactive aerosol particles produced in the intense radiation fields of radiation facilities.

  12. Study of particle size distribution and formation mechanism of radioactive aerosols generated in high-energy neutron fields

    CERN Document Server

    Endo, A; Noguchi, H; Tanaka, S; Iida, T; Furuichi, S; Kanda, Y; Oki, Y

    2003-01-01

    The size distributions of sup 3 sup 8 Cl, sup 3 sup 9 Cl, sup 8 sup 2 Br and sup 8 sup 4 Br aerosols generated by irradiations of argon and krypton gases containing di-octyl phthalate (DOP) aerosols with 45 MeV and 65 MeV quasi-monoenergetic neutrons were measured in order to study the formation mechanism of radioactive particles in high energy radiation fields. The effects of the size distribution of the radioactive aerosols on the size of the added DOP aerosols, the energy of the neutrons and the kinds of nuclides were studied. The observed size distributions of the radioactive particles were explained by attachment of the radioactive atoms generated by the neutron-induced reactions to the DOP aerosols. (author)

  13. Natural and artificial radioactivity in the area of the Mochovce regional radioactive waste store

    International Nuclear Information System (INIS)

    Bezak, J.; Daniel, J.; Moravek, J.

    2000-01-01

    The results of monitoring of natural and artificial radioactivity in the area of the Mochovce regional radioactive waste store before commission are presented. The concentrations of uranium, thorium, potassium, and cesium, as well as radon volume activity were measured

  14. Density and radioactivity distribution of respirable range human serum albumin aerosol

    International Nuclear Information System (INIS)

    Raghunath, B.; Somasundaram, S.; Soni, P.S.

    1988-01-01

    Dry human serum albumin (HSA) aerosol in the respirable size range was generated using the BARC nebulizer. The aerosol was sampled using Lovelace Aerosol Particle Separator (LAPS) and the density of HSA was determined. Labelling of HSA with 99m TcO 4 - was done, both in HSA solution and with dry denatured HSA particles, to study the distribution of radioactivity in both cases. The results are discussed. (author)

  15. Bronchial and pulmonary scintigraphy with radioactively marked aerosols

    International Nuclear Information System (INIS)

    Wuerstle, T.

    1982-01-01

    In 97 patients with bronchitis, bronchial asthma, tuberculosis, sarcoidosis, pneumoconiosis, or tumors the mucociliary clearance and/or deposit pattern after inhalation of radioactively marked aerosols (1 mCi 99m Tc sulfur colloid) was studied. Normal values of the mucociliary 30 min. clearance for the central bronchial/lung periphery are 21%/15%. There was a decreased clearance with bronchitis (11/8%), bronchial asthma, emphysema, tuberculosis, sarcoidosis, trachiobronchial amyloidosis, pleural scarring or interstitial pneumona. Increased clearance (29/19%) was shown with pneumoconiosis. The correlation of deposit pattern and disease, for example, bronchitis, bronchial asthma, bullous emphysema, pleural scarring, partial lung resection, bronchopneumonia, or bronchial restriction, is described. In comparison of aerosol scintigraphy to perfusion scintigraphy and ventilation with gaseous xenon, the aerosol scintigraphy is superior to xenon for certain indications. The aerosol particles, which are larger in comparison to xenon, settle easier by obstructions or flow variations and thereby give better clinical indications of regional differences. (orig.) [de

  16. Radioactive aerosol detection station for near real-time atmospheric monitoring

    International Nuclear Information System (INIS)

    Mason, L.R.; Bohner, John D.

    1997-01-01

    A radionuclide aerosol detection station has been developed to measure radioactivity in the environment. The objective is to monitor the atmosphere for anthropogenic radioactivity that could be indicative of nuclear weapons tests to verify the Comprehensive Nuclear Test Ban Treaty. Eighty stations will form the backbone of the International Monitoring System in which stations are linked to a central analysis facility called the International Data Centre. Data are transmitted to this centre in near real-time to facilitate rapid detection. Principal process of the field measurement are collection, separation, and assay. Collection of airborne radioactivity is achieved through high-volume air sampling. Aerosols separation is accomplished by high-efficiency particulate filtration. Radionuclides assay is achieved by in-situ high resolution gamma spectrometry. These modules are integrated into a unit that provides power, control, and communication support subsystems. Station operation is semi-automatic requiring only minimal human interaction. (author). 6 refs., 3 figs., 3 tabs

  17. Radiological observation: 'remanence of radioactivity of artificial origin'. Mission report 2016

    International Nuclear Information System (INIS)

    Aubry, S.; Boulet, B.; Cagnat, X.; Cossonnet, C.; Mekhlouche, D.; Thomas, S.; Vivien, C.; Chevreuil, M.; Malfait, V.; Manach, E.; Claval, D.; Mourier, D.; Pourcelot, L.; Salaun, G.; Metivier, J.M.

    2016-04-01

    Thirty years after the Chernobyl accident, some areas in France, mainly mountain areas, display radioactivity levels higher or even much higher than those noticed in other areas, even at the vicinity of nuclear plants. These areas are called 'areas of remanence of artificial radioactivity'. After having recalled this observation based on radiological measurements, and an overview of an atmospheric deposition of artificial radioactivity (nuclear tests, Chernobyl accident, satellite falls, Fukushima accident), this report describes the adopted strategy (sampling and measurements) to assess and study this phenomenon. It analyses the obtained results in terms of remanence in the continental water environment and in soils, fields and forests. It also proposes a synthesis of previously acquired results. Appendices present methods used for sampling and sample processing, a list of samples, data related to mass activity of artificial radioactivity in soils, inventories of artificial radioactivity in soils, and methods for the calculation of efficient doses

  18. Determination of the aerosol filters efficiency by means of the tracer techniques

    International Nuclear Information System (INIS)

    Hirling, J.

    1978-01-01

    Estimation of the nonradioactive methods of filters efficiency determination and tracer techniques are given. The methods are stated and discriptions of the instrumentation for estimation of the filters efficiency are given, in particular: methodology of production of the radioactive synthetic test-aerosols by means of the disperse and steamcondensation aerosol generators; the radio isotope method of the aerosol filters investigations; the methodology of filtartion efficiency determination. The results are given of the radioisotope investigations of filters; properties of the artificial radioactive test-aerosols; characteristics of filters, determined by the tracer techniques. Curves are given for the filtration efficiency of the viscose filtering nozzles of different density depending on the filters load. (I.T.) [ru

  19. The use of an experimental device for the determination of the concentration of artificial radioactive aerosols at high altitudes

    International Nuclear Information System (INIS)

    Boclet, D.; Jehanno, C.; Labeyrie, J.

    1960-01-01

    By means of measurements with a Geiger counter on january, the 27 th , in 1959 at an altitude reaching 65 km approximately, and following comparison with similar measurements made by Gangnes, Jenkins and Van Allen in 1949 at the same geomagnetic latitude (41 deg. North), it is concluded that radioactive aerosols above Southern France tropopause had a concentration less than 100.10 -12 curies/m 3 at that time. The missile used for this purpose and its performance are quickly described in this paper. (author) [fr

  20. Note: Real time optical sensing of alpha-radiation emitting radioactive aerosols based on solid state nuclear track detector

    International Nuclear Information System (INIS)

    Kulkarni, A.; Bak, M. S.; Ha, S.; Joshirao, P.; Manchanda, V.; Kim, T.

    2015-01-01

    A sensitive radioactive aerosols sensor has been designed and developed. Its design guidance is based on the need for a low operational cost and reliable measurements to provide daily aerosol monitoring. The exposure of diethylene-glycol bis (allylcarbonate) to radiation causes modification of its physico-chemical properties like surface roughness and reflectance. In the present study, optical sensor based on the reflectance measurement has been developed with an aim to monitor real time presence of alpha radioactive aerosols emitted from thorium nitrate hydrate. The results shows that the fabricated sensor can detect 0.0157 kBq to 0.1572 kBq of radio activity by radioactive aerosols generated from (Th(NO 3 ) 4 ⋅ 5H 2 O) at 0.1 ml/min flow rate. The proposed instrument will be helpful to monitor radioactive aerosols in/around a nuclear facility, building construction sites, mines, and granite polishing factories

  1. Note: Real time optical sensing of alpha-radiation emitting radioactive aerosols based on solid state nuclear track detector

    Science.gov (United States)

    Kulkarni, A.; Ha, S.; Joshirao, P.; Manchanda, V.; Bak, M. S.; Kim, T.

    2015-06-01

    A sensitive radioactive aerosols sensor has been designed and developed. Its design guidance is based on the need for a low operational cost and reliable measurements to provide daily aerosol monitoring. The exposure of diethylene-glycol bis (allylcarbonate) to radiation causes modification of its physico-chemical properties like surface roughness and reflectance. In the present study, optical sensor based on the reflectance measurement has been developed with an aim to monitor real time presence of alpha radioactive aerosols emitted from thorium nitrate hydrate. The results shows that the fabricated sensor can detect 0.0157 kBq to 0.1572 kBq of radio activity by radioactive aerosols generated from (Th(NO3)4 ṡ 5H2O) at 0.1 ml/min flow rate. The proposed instrument will be helpful to monitor radioactive aerosols in/around a nuclear facility, building construction sites, mines, and granite polishing factories.

  2. Note: Real time optical sensing of alpha-radiation emitting radioactive aerosols based on solid state nuclear track detector

    Energy Technology Data Exchange (ETDEWEB)

    Kulkarni, A.; Bak, M. S., E-mail: tkim@skku.edu, E-mail: moonsoo@skku.edu [School of Mechanical Engineering, Sungkyunkwan University, Suwon 440-746 (Korea, Republic of); Ha, S. [SKKU Advanced Institute of Nano Technology (SAINT), Sungkyunkwan University, Suwon 440-746 (Korea, Republic of); Joshirao, P.; Manchanda, V. [Department of Energy Science, Sungkyunkwan University, Suwon 440-746 (Korea, Republic of); Kim, T., E-mail: tkim@skku.edu, E-mail: moonsoo@skku.edu [School of Mechanical Engineering, Sungkyunkwan University, Suwon 440-746 (Korea, Republic of); SKKU Advanced Institute of Nano Technology (SAINT), Sungkyunkwan University, Suwon 440-746 (Korea, Republic of)

    2015-06-15

    A sensitive radioactive aerosols sensor has been designed and developed. Its design guidance is based on the need for a low operational cost and reliable measurements to provide daily aerosol monitoring. The exposure of diethylene-glycol bis (allylcarbonate) to radiation causes modification of its physico-chemical properties like surface roughness and reflectance. In the present study, optical sensor based on the reflectance measurement has been developed with an aim to monitor real time presence of alpha radioactive aerosols emitted from thorium nitrate hydrate. The results shows that the fabricated sensor can detect 0.0157 kBq to 0.1572 kBq of radio activity by radioactive aerosols generated from (Th(NO{sub 3}){sub 4} ⋅ 5H{sub 2}O) at 0.1 ml/min flow rate. The proposed instrument will be helpful to monitor radioactive aerosols in/around a nuclear facility, building construction sites, mines, and granite polishing factories.

  3. Code Development of Radioactive Aerosol Scrubbing in Pool-Injection Zone

    Energy Technology Data Exchange (ETDEWEB)

    Jo, Hyun Joung; Ha, Kwang Soon [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of); Jang, Dong Soon [Chungnam National University, Daejeon (Korea, Republic of)

    2015-10-15

    The pool scrubbing models were reviewed and an aerosol scrubbing code has been prepared to calculate decontamination factor through the injection zone. The developed code has been verified using the experimental results and evaluated parametrically on the input variables. In injection zone, the initial steam condensation was most effective mechanism for the aerosol removal, and the steam fraction and pool temperature were highly affected on the decontamination factor by initial steam condensation. The aerosol scrubbing code will be updated to evaluate the decontamination factor at rise zone and finally whole pool scrubber phenomena. If a severe accident occurs in a nuclear power plant (NPP), the aerosol and gaseous fission products might be produced in the reactor vessel, and then released to the environment after the containment failure. FCVS (Filtered Containment Venting System) is one of the severe accident mitigation systems for retaining the containment integrity by discharging the high-temperature and high-pressure fission products to the environment after passing through the filtration system. In general, the FCVS is categorized into two types, wet and dry types. The scrubbing pool could play an important role in the wet type FCVS because a large amount of aerosol is captured in the water pool. The pool scrubbing phenomena have been modelled and embedded in several computer codes, such as SPARC (Suppression Pool Aerosol Removal Code), BUSCA (BUbble Scrubbing Algorithm) and SUPRA (Suppression Pool Retention Analysis). These codes aim at simulating the pool scrubbing process and estimating the decontamination factors (DFs) of the radioactive aerosol and iodine gas in the water pool, which is defined as the ratio of initial mass of the specific radioactive material to final massy after passing through the water pool. The pool scrubbing models were reviewed and an aerosol scrubbing code has been prepared to calculate decontamination factor through the injection

  4. Natural and Artificial Radioactivity in Drinkingwater in Malaga, Spain

    Energy Technology Data Exchange (ETDEWEB)

    Fernandez, M. C.; Duenas, C.; Gordo, E.; Canete, S. [Department of Applied Physics I, Faculty of Science, University of Malaga (Spain); Perez, M. [Department of Radiology and Health Physics, Faculty of Medicine, University of Malaga, Malaga (Spain)

    2013-07-15

    The measurement of radioactivity in drinking water permits us to determine the exposure of the 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 and gross beta activities and natural and artificial radionuclides present in drinking water. A database on natural and artificial radioactivity in water was created. The results indicated that a high percentage of the water sample contains a total gross alpha and beta concentration of less than 0.10 Bq/L and 1 Bq/L, respectively. The main objectives were: (1) to analyse 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. (author)

  5. A new code for spectrometric analysis for environmental radiological surveillance on monitors focused on gamma radioactivity on aerosols

    Energy Technology Data Exchange (ETDEWEB)

    De Blas, Alfredo; Tapia, Carlos; Riego, Albert; Garcia, Roger; Dies, Javier; Diaz, Pedro [Nuclear Engineering Research Group, Departament of Physics and Nuclear Engineering, Technical University of Catalonia, Barcelona (Spain); Toral, Juan [Raditel Serveis, Tarragona (Spain); Batalla, Enric [Radiological Activities Corrdination Service - SCAR, Generalitat de Catalunya. Barcelona (Spain)

    2015-07-01

    pGamma is a code developed by the NERG group of the Technical University of Catalonia - Barcelona Tech for the analysis of gamma spectra generated by the Equipment for the Continuous Measurement and Identification of Gamma Radioactivity on Aerosols with Paper Filter developed for our group and Raditel Servies company. Nowadays the code is in the process of adaptation for the monitors of the Environmental Radiological Surveillance Network of the Local Government of Catalonia (Generalitat of Catalonia), Spain. The code is a Spectrum Analysis System, it identifies the gamma emitters on the spectrum, determines its Concentration of Activity, generates alarms depending on the Activity of the emitters and generates a report. The Spectrum Analysis System includes a library with emitters of interest, NORM and artificial. The code is being used on the three stations with the aerosol monitor of the Network (Asco and Vandellos, near both Nuclear Power Plants and Barcelona). (authors)

  6. Radioactive aerosols of the object 'Ukryttya' (a review). Part 4.2. Sources and generation of radioactive aerosols during technogenic activities in 1987 - 2005

    International Nuclear Information System (INIS)

    Ogorodnikov, B.I.; Pazukhin, Eh.M.

    2006-01-01

    The sources of radioactive aerosol formation were considered at operation. It is shown that concentrations, radionuclide composition, size distribution, transfer and transformation in environment depended on physical and chemical processes proceeding within reactor breakdown, man-caused activity into premises of the object 'Shelter' and near ChNPP. 34 refs.; 7 figs.; 11 tab

  7. Removal of nitrogen oxides, 106RuO4 vapors and radioactive aerosols from the gas originating in radioactive wastes solidification

    International Nuclear Information System (INIS)

    Kepak, F.; Pecak, V.; Uher, E.; Kanka, J.; Koutova, S.; Matous, V.

    1985-01-01

    Procedures and equipment for the disposal of nitrogen oxides, RuO 4 vapors and radioactive aerosols of 90 Sr, 137 Cs, 60 Co and 125 Sb contained in the gas generated in the solidification of high- and intermediate-level radioactive wastes were tested on models. Nitrogen oxides were disposed of by absorption and chemical decomposition in various solutions of which the best results gave solutions of ammonium salts. Absorption in solutions, physical and chemical sorption on inorganic sorbents were tested for the disposal of RuO 4 . Aerosols were disposed of by absorption in absorption media with subsequent filtration. Of fibrous filter materials, Czechoslovak AEROS-2 and RA-2 filter papers were proven in the tests. Attention was also devoted to granular filter materials of which silica gel was chosen. On the basis of laboratory tests a multi-step treatment system was designed which consists of a condenser, a nitrogen oxide absorber, a liquid aerosol separator, absorption columns and aerosol filters. The whole system has been manufactured on pilot plant scale and the different parts are being produced. (Z.M.)

  8. Single particle composition measurements of artificial Calcium Carbonate aerosols

    Science.gov (United States)

    Zorn, S. R.; Mentel, T. F.; Schwinger, T.; Croteau, P. L.; Jayne, J.; Worsnop, D. R.; Trimborn, A.

    2012-12-01

    Mineral dust, with an estimated total source from natural and anthropogenic emissions of up to 2800 Tg/yr, is one of the two largest contributors to total aerosol mass, with only Sea salt having a similar source strength (up to 2600 Tg/yr). The composition of dust particles varies strongly depending on the production process and, most importantly, the source location. Therefore, the composition of single dust particles can be used both to trace source regions of air masses as well as to identify chemical aging processes. Here we present results of laboratory studies on generating artificial calcium carbonate (CaCO3) particles, a model compound for carbonaceous mineral dust particles. Particles were generated by atomizing an aqueous hydrogen carbonate solution. Water was removed using a silica diffusion dryer., then the particles were processed in an oven at temperatures up to 900°C, converting the hydrogen carbonate to its anhydrous form. The resulting aerosol was analyzed using an on-line single particle laser ablation aerosol particle time-of-flight mass spectrometer (LAAPTOF). The results confirm the conversion to calcium carbonate, and validate that the produced particles indeed can be used as a model compound for carbonaceous dust aerosols.

  9. Demolition and removal of radioactively contaminated concrete soil: Aerosol control and monitoring

    Energy Technology Data Exchange (ETDEWEB)

    Newton, G.J.; Hoover, M.D.; Grace, A.C. III

    1995-12-01

    From 1963 to 1985, two concrete-lined ponds were used to reduce the volume of radioactive liquids from the Institute`s research programs. Following withdrawal of the {open_quotes}hot ponds{close_quotes} from active use, the residual sludges and plastic liners of the ponds were removed and shipped to a radioactive waste disposal site. From 1987 to 1994, the concrete structures remained undisturbed pending environmental restoration on the site. Restoration began in 1994 and was completed in 1995. Restoration involved mechanical breakup and removal of the concrete structures and removal of areas of contaminated soils from the site. This report describes the design and results of the aerosol control and monitoring program that was conducted to ensure protection of workers and the environment during the restoration process. The aerosol control and monitoring strategy developed for remediation of the ITRI hot ponds was successful both in preventing dispersion of radioactive dusts and in demonstrating that exposures of workers and offsite releases were within statutory limits.

  10. Experimental study of radioactive aerosols in the vicinity of the Chernobyl Nuclear Power Plant

    International Nuclear Information System (INIS)

    Boulyga, S.F.; Lomonosova, E.M.; Zhuk, I.V.; Yaroshevich, O.I.; Kudrjashov, V.P.; Mironov, V.P.

    1999-01-01

    Study of radioactive aerosols in the relocation zone and in the populated areas have been carried out for a number of years. The experiments on modelling resuspension were performed while conducting agricultural work. Nuclear track radiography and alpha spectrometry with radiochemical extraction of plutonium were used as analytical methods for the determination of the transuranium elements contents. The distributions of radioactive particles were obtained as to activity and sizes. Specific activity of 'hot particles' increases with decreasing diameter. In aerosols selected at a distance of more than 10 km from the Chernobyl NPP pure fuel particles with sizes of more than 5 μm were not found. The activity of the finely dispersed fraction of aerosols, which is more dangerous when inhaled by the organism, is comparable with a total activity of large particles

  11. EMSP Final Report: Electrically Driven Technologies for Radioactive Aerosol Abatement

    Energy Technology Data Exchange (ETDEWEB)

    DePaoli, D.W.

    2003-01-22

    The purpose of this research project was to develop an improved understanding of how electrically driven processes, including electrocoalescence, acoustic agglomeration, and electric filtration, may be employed to efficiently treat problems caused by the formation of aerosols during DOE waste treatment operations. The production of aerosols during treatment and retrieval operations in radioactive waste tanks and during thermal treatment operations such as calcination presents a significant problem of cost, worker exposure, potential for release, and increased waste volume. There was anecdotal evidence in the literature that acoustic agglomeration and electrical coalescence could be used together to change the size distribution of aerosol particles in such a way as to promote easier filtration and less frequent maintenance of filtration systems. As such, those electrically driven technologies could potentially be used as remote technologies for improved treatment; however, existing theoretical models are not suitable for prediction and design. To investigate the physics of such systems, and also to prototype a system for such processes, a collaborative project was undertaken between Oak Ridge National Laboratory (ORNL) and the University of Texas at Austin (UT). ORNL was responsible for the larger-scale prototyping portion of the project, while UT was primarily responsible for the detailed physics in smaller scale unit reactors. It was found that both electrical coalescence and acoustic agglomeration do in fact increase the rate of aggregation of aerosols. Electrical coalescence requires significantly less input power than acoustic agglomeration, but it is much less effective in its ability to aggregate/coalesce aerosols. The larger-scale prototype showed qualitatively similar results as the unit reactor tests, but presented more difficulty in interpretation of the results because of the complex multi-physics coupling that necessarily occur in all larger

  12. On the discovery of artificial radioactivity

    International Nuclear Information System (INIS)

    Guillaumont, R.; Trubert, D.

    1997-01-01

    A review is presented of the elegant Joliot-Curie physical experiments which showed for the first time the possibility of producing artificial radioactive nuclei. An attempt has been made to explain the results of their equally elegant chemical experiments that unequivocally demonstrated the chemical change of elements by nuclear processes. These experiments are discussed in the light of present-day radiochemistry, keeping in mind the scientific and historical context in which they were originally performed. (author)

  13. Experimental study of radioactive aerosols in the vicinity of the Chernobyl Nuclear Power Plant

    Energy Technology Data Exchange (ETDEWEB)

    Boulyga, S.F.; Lomonosova, E.M.; Zhuk, I.V.; Yaroshevich, O.I.; Kudrjashov, V.P.; Mironov, V.P

    1999-12-01

    Study of radioactive aerosols in the relocation zone and in the populated areas have been carried out for a number of years. The experiments on modelling resuspension were performed while conducting agricultural work. Nuclear track radiography and alpha spectrometry with radiochemical extraction of plutonium were used as analytical methods for the determination of the transuranium elements contents. The distributions of radioactive particles were obtained as to activity and sizes. Specific activity of 'hot particles' increases with decreasing diameter. In aerosols selected at a distance of more than 10 km from the Chernobyl NPP pure fuel particles with sizes of more than 5 {mu}m were not found. The activity of the finely dispersed fraction of aerosols, which is more dangerous when inhaled by the organism, is comparable with a total activity of large particles.

  14. Adsorption of radioactive I2 gas onto fly-ash aerosol

    International Nuclear Information System (INIS)

    Noguchi, Hiroshi; Murata, Mikio; Suzuki, Katsumi.

    1988-01-01

    The adsorption of radioactive elemental iodine (I 2 ) gas onto fly-ash aerosol has been studied to provide basic data for the realistic and precise assessment of dose to the general public from radioiodine released from nuclear facilities. A mixture of fly-ash aerosol and 131 I 2 gas was passed through a cylindrical glass vessel so that particulate iodine was formed by adsorption of I 2 onto aerosol. Then the concentrations of I 2 and particulate iodine were measured. It was found that the adsorption reached an equilibrium state between 5 and 12 min and that the proportion of iodine which was adsorbed on the aerosol decreased with increasing initial I 2 concentration ranging over 10 -13 to 10 -9 g/cm 3 . The adsorption isotherm of the aerosol for I 2 gas approximately followed Freundlich isotherm. Using the adsorption isotherm, a theoretical equation was derived to explain the adsorption on the basis of FUCHS' theory on the evaporation of droplets. A sticking probability in the equation decreased with increasing adsorbed amount. The calculated results were in good agreement with the experimental ones. (author)

  15. Environmental pollution: influence on the operation of a sensor of radioactive aerosols

    International Nuclear Information System (INIS)

    Duarte Rodriguez, X.; Hernandez Armas, J.; Martin Delgado, J.; Rodriguez Perestelo, N.; Perez Lopez, M.; Catalan Acosta, A.; Fernandez de Aldecoa, J. c.

    2013-01-01

    The content of radioactive aerosols in the air is an important component to estimate the ambient radiation dose. In the laboratories of environmental radioactivity, measurements of radionuclides in air they are performed using sensors. The flow picked up by the equipment can be changed if the degree of air pollution changes for some reason. It handles this study and the population doses are estimated due to inhalation of ambient air. (Author)

  16. Experimental study of contamination by inhalation of radioactive iodine aerosols. Biological balance

    International Nuclear Information System (INIS)

    Marble, G.

    1968-01-01

    Several articles have been published concerning research into contamination produced by inhalation of radioactive iodine aerosols in monkeys. Results dealing with the biological balance of this contamination are presented and discussed in this report. (author) [fr

  17. Development and validation of the aerosol transport module gamma-FP for evaluating radioactive fission product source terms in a VHTR

    Energy Technology Data Exchange (ETDEWEB)

    Yoon, Churl; Lim, Hong Sik [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2014-12-15

    Predicting radioactive fission product (FP) behaviors in the reactor coolant system and the containment of a nuclear power plant (NPP) is one of the major concerns in the field of reactor safety, since the amount of radioactive FP released into the environment during the postulated accident sequences is one of the major regulatory issues. Radioactive FPs circulating in the primary coolant loop and released into the containment are basically in the form of gas or aerosol. In this study, a multi-component and multi-sectional analysis module for aerosol fission products has been developed based on the MAEROS model, and the aerosol transport model has been developed and verified against an analytic solution. The deposition of aerosol FPs to the surrounding structural surfaces is modeled with recent research achievements. The developed aerosol analysis model has been successfully validated against the STORM SR-11 experimental data, which is International Standard Problem No. 40. Future studies include the development of the resuspension, growth, and chemical reaction models of aerosol fission products.

  18. Adsorption of radioactive I2 gas onto atmospheric aerosol

    International Nuclear Information System (INIS)

    Noguchi, Hiroshi; Murata, Mikio; Suzuki, Katsumi.

    1990-01-01

    Laboratory scale experiments on the adsorption of radioactive elemental iodine (I 2 ) gas onto atmospheric aerosol showed that the adsorption reached an equilibrium state in about twelve minutes at high initial I 2 concentrations. The proportion of iodine which was adsorbed on the aerosol gradually decreased with increading initial I 2 concentration ranging over 10 -13 to 10 -9 g/cm 3 at a reaction time of 31 min but was almost constant at a reaction time of 2 min. A fraction of iodine desorbed from particulate iodine as mainly I 2 gas. An adsorption isotherm of atmospheric aerosol for I 2 gas was estimated from the experimental data of long reaction time and high I 2 concentrations. Using this adsorption isotherm, a theoretical equation, which was similar to our previous equation, was derived to explain the experimental results. A geometric mean and standard deviation of sticking probability in the equation were estimated to be 1.2 x 10 -2 and 2.7, respectively. Almost all experimental data were within ranges of calculated results considering the geometric standard deviation of sticking probability. (author)

  19. Monitoring of the release of gaseous and aerosol-bound radioactive materials. Pt. 2

    International Nuclear Information System (INIS)

    1992-01-01

    KTA 1503 contains requirements on technical installations and supplementary organizational measures considered necessary in order to monitor the release of gaseous and aerosol-bound radioactive materials. It consists of part 1: Monitoring of the release of radioactive materials together with stack gas during normal operation; part 2: Monitoring of the release of radioactive materials together with stack gas in the event of incidents; part 3: Monitoring of radioactive materials not released together with stack gas. The concept on which this rule is based is to ensure that in the case of incidents during which the result of effluent monitoring remains meaningful, such monitoring can be reliably performed. (orig./HSCH) [de

  20. 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.

  1. Measurement of radioactive aerosols as an original indicator of atmospheric pollution in urban areas

    International Nuclear Information System (INIS)

    Le Petit, G.; Millies-Lacroix, J. C.

    1998-01-01

    The Service Radioanalyses, Chimie et Environnment (Departement Analyses Surveillance de l'Environnement) of the French Atomic Energy Commission, located in suburban Paris, has for many years been conducting atmospheric radioactivity measurements. Since 1994, the laboratory has been using high volume air samplers equipped with filters for the weekly collection of atmospheric aerosols at a mean rate of about 600 m 3 .h -1 . The polypropylene filters, with a collection efficiency in excess of 93%, are compacted after sampling. The atmospheric radioactivity is measured by HP Ge gamma spectrometry after decay of short-lived natural relationship products. A study conducted in 1996 shows good correlation between the evolution with time of some of the indicators routinely used by AIRPARIF, the organization in charge of monitoring the air quality in the Ile-de-France region, to measure atmospheric pollution in the Paris area (SO 2 , NO) and that related to radioactivity of terrestrial ( 210 Pb, 40 K) and anthropogenic ( 137 Cs) origin, as well as the amount of aerosols collected. Further, the distribution in time of the atmospheric radioactivity of cosmogenic origin ( 7 Be) shows a yearly evolution somewhat similar to that observed with ozone

  2. Formation and evolution of aerosols in filtered air and in natural air. Effect of radioactivity; Formation et evolution des aerosols dans l'air filtre et dans l'air naturel action de la radioactivite

    Energy Technology Data Exchange (ETDEWEB)

    Madelaine, G J [Commissariat a l' Energie Atomique, 92 - Fontenay-aux-Roses (France). Centre d' Etudes Nucleaires

    1968-06-01

    Results are presented concerning the formation, the evolution, the coagulation and the electrical charge of aerosols which form in natural filtered air containing only gaseous impurities, under the influence of solar light (photolysis) and of radioactive disintegrations (radiolysis). The modifications brought about in the aerosol by an increase in the sulphur dioxide content and in the natural radioactive gas content are studied. The work is then repeated with non-filtered natural atmospheric air. A comparison is also made of the behaviour of non-radioactive and radioactive particles (active thoron deposit). In conclusion, the possible consequences of these phenomena on the origin and the size distribution of particles occurring in the atmosphere is considered. (author) [French] On expose les resultats obtenus sur la formation, l'evolution, la coagulation et la charge electrique des aerosols qui se forment dans l'air naturel filtre, ne contenant que des impuretes gazeuses, sous l'influence de la lumiere solaire (photolyse) et des desintegrations radioactives (radiolyse). On examine les modifications apportees a l'aerosol forme par l'augmentation de la teneur de l'air en anhydride sulfureux et en gaz radioactif naturel. Cette etude est ensuite reprise mais avec de l'air naturel atmospherique non filtre. On compare egalement le comportement des particules non radioactives et radioactives (depot actif du thoron). En conclusion, on examine les consequences que peuvent avoir ces phenomenes sur l'origine et la granulometrie des particules contenues dans l'atmosphere. (auteur)

  3. Development of an aerosol decontamination factor evaluation method using an aerosol spectrometer

    International Nuclear Information System (INIS)

    Kanai, Taizo; Furuya, Masahiro; Arai, Takahiro; Nishi, Yoshihisa

    2016-01-01

    Highlights: • Aerosol DF of each diameter is evaluable by using optical scattering method. • Outlet aerosol concentration shows exponential decay by the submergence. • This decay constant depends on the aerosol diameter. • Aerosol DF at water scrubber is described by simple equation. - Abstract: During a severe nuclear power plant accident, the release of fission products into containment and an increase in containment pressure are assumed to be possible. When the containment is damaged by excess pressure or temperature, radioactive materials are released. Pressure suppression pools, containment spray systems and a filtered containment venting system (FCVS) reduce containment pressure and reduce the radioactive release into the environment. These devices remove radioactive materials via various mechanisms. Pressure suppression pools remove radioactive materials by pool scrubbing. Spray systems remove radioactive materials by droplet−aerosol interaction. FCVS, which is installed in the exhaust system, comprises multi-scrubbers (venturi-scrubber, pool scrubbing, static mixer, metal−fiber filter and molecular sieve). For the particulate radioactive materials, its size affects the removal performance and a number of studies have been performed on the removal effect of radioactive materials. This study has developed a new means of evaluating aerosol removal efficiency. The aerosol number density of each effective diameter (light scattering equivalent diameter) is measured using an optical method, while the decontamination factor (DF) of each effective diameter is evaluated by the inlet outlet number density ratio. While the applicable scope is limited to several conditions (geometry of test section: inner diameter 500 mm × height 8.0 m, nozzle shape and air-water ambient pressure conditions), this study has developed a numerical model which defines aerosol DF as a function of aerosol diameter (d) and submergences (x).

  4. Development of an aerosol decontamination factor evaluation method using an aerosol spectrometer

    Energy Technology Data Exchange (ETDEWEB)

    Kanai, Taizo, E-mail: t-kanai@criepi.denken.or.jp; Furuya, Masahiro, E-mail: furuya@criepi.denken.or.jp; Arai, Takahiro, E-mail: t-arai@criepi.denken.or.jp; Nishi, Yoshihisa, E-mail: y-nishi@criepi.denken.or.jp

    2016-07-15

    Highlights: • Aerosol DF of each diameter is evaluable by using optical scattering method. • Outlet aerosol concentration shows exponential decay by the submergence. • This decay constant depends on the aerosol diameter. • Aerosol DF at water scrubber is described by simple equation. - Abstract: During a severe nuclear power plant accident, the release of fission products into containment and an increase in containment pressure are assumed to be possible. When the containment is damaged by excess pressure or temperature, radioactive materials are released. Pressure suppression pools, containment spray systems and a filtered containment venting system (FCVS) reduce containment pressure and reduce the radioactive release into the environment. These devices remove radioactive materials via various mechanisms. Pressure suppression pools remove radioactive materials by pool scrubbing. Spray systems remove radioactive materials by droplet−aerosol interaction. FCVS, which is installed in the exhaust system, comprises multi-scrubbers (venturi-scrubber, pool scrubbing, static mixer, metal−fiber filter and molecular sieve). For the particulate radioactive materials, its size affects the removal performance and a number of studies have been performed on the removal effect of radioactive materials. This study has developed a new means of evaluating aerosol removal efficiency. The aerosol number density of each effective diameter (light scattering equivalent diameter) is measured using an optical method, while the decontamination factor (DF) of each effective diameter is evaluated by the inlet outlet number density ratio. While the applicable scope is limited to several conditions (geometry of test section: inner diameter 500 mm × height 8.0 m, nozzle shape and air-water ambient pressure conditions), this study has developed a numerical model which defines aerosol DF as a function of aerosol diameter (d) and submergences (x).

  5. Measurement of radioactive aerosols as an original indicator of atmospheric pollution in urban areas

    International Nuclear Information System (INIS)

    Le Petit, G.; Millies-Lacroix, J.-C.; Simon, F.

    1998-01-01

    The Service Radioanalyses, Chimie et Environnement (Departement Analyses Surveillance de l'Environnement) of the French Atomic Energy Commission, located in suburban Paris, has for many years been conducting atmospheric radioactivity measurements. Since 1994, the laboratory has been using high volume air samplers equipped with filters for the weekly collection of atmospheric aerosols at a mean rate of about 600 m 3 .h -1 . The polypropylene filters, with a collection efficiency in excess of 93%, are compacted after sampling. The atmospheric radioactivity is measured by HP Ge gamma spectrometry after decay of short-lived natural relationship products. A study conducted in 1996 shows good correlation between the evolution with time of some of the indicators routinely used by AIRPARIF, the organization in charge of monitoring of the air quality in the Ile-de-France region, to measure atmospheric pollution in the Paris area (SO 2 , NO) and that related to radioactivity of terrestrial ( 210 Pb, 40 K) and anthropogenic ( 137 Cs) origin, as well as the amount of aerosols collected. Further, the distribution in time of the atmospheric radioactivity of cosmogenic origin ( 7 Be) shows a yearly evolution somewhat similar to that observed with ozone. (author). 16 refs., 21 figs., 1 tab

  6. A contribution to the study of the physical properties of natural and radioactive aerosols in controlled atmospheres

    International Nuclear Information System (INIS)

    Mouden, A.

    1986-01-01

    The major objective of this work was to study the properties of normal and radioactive particles produced by attachment of radon 222 daughters on environmental aerosol particles, in various and controlled atmospheres. In the first part, devoted to the radioactivity of radon 222, the influence of the number of nuclei on the radioactive equilibrium state and the size distribution of alpha radioactivity was demonstrated. In the second part, an experimental study of the C.E.A. α dosimeter was developed. We investigated the counting and the collection efficiency of the dosimeter for inlet particles in the 0.001-0.1 μm size range. The last part concerns aerosol-filtration behaviour. The comparison between experimental and theoretical procedures revealed a good agreement only in some circumstances for membrane filters. In the case of fibrous filters the agreement is quite satisfactory. Particularly, if the fiber size distribution is taken into account in the theoretical model, it results in an improved estimation of the collection efficiency [fr

  7. Calibration of aerosol radiometers. Special aerosol sources

    International Nuclear Information System (INIS)

    Belkina, S.K.; Zalmanzon, Yu.E.; Kuznetsov, Yu.V.; Fertman, D.E.

    1988-01-01

    Problems of calibration of artificial aerosol radiometry and information-measurement systems of radiometer radiation control, in particular, are considered. Special aerosol source is suggested, which permits to perform certification and testing of aerosol channels of the systems in situ without the dismantling

  8. The artificial radioactivity in Bechet-Dabuleni area, five years of survey

    International Nuclear Information System (INIS)

    Dobrescu, E.; Milu, C.; Gheorghe, R.; Lida, F.; Gruia, D.

    1996-01-01

    The Bechet-Dabuleni area is placed in the southern part of Romania, in the Danube zone, near the Nuclear Power Plant from Kozlodui (Bulgaria). Here there is a very important agricultural area, with small and also big farms where for irrigation the Danube water is used. The purpose of the study was was long term surveillance of the artificial radioactivity for the main foodstuffs. It has been investigated the radioactive content of the following foodstuffs from this area: vegetables (potatoes, carrots, onion, etc.), fruits (apples, pears, apricots, peaches) and cereals (wheat, barley). It has also been determined the radioactive content of the irrigating water from the Danube River. (author)

  9. Artificial neural network models' application for radioactive substances' migration forecasting in soil

    International Nuclear Information System (INIS)

    Kovalenko, V.I.; Khil'ko, O.S.; Kundas, S.P.

    2009-01-01

    The work is indicated to the use of artificial neural network (ANN) models in program complex SPS for radioactive substances' migration forecasting in soil. For the problem solution two ANN models are used. One of them forecasts radioactive substances' migration, another carries out forecasting of physical and chemical soil properties. Program complex SPS allows to achieve a low error of forecasting (no more than 5 %) and high training speed. (authors)

  10. Measurement of radioactive aerosol behavior during dismantling and reflection to the exposure dose evaluation - 16107

    International Nuclear Information System (INIS)

    Iguchi, Yukihiro; Kato, Masami

    2009-01-01

    Radioactive aerosol disperses slightly via contamination prevention systems such as control enclosures and filters when the nuclear installation is dismantled, and it might impact the environment. Therefore, when decommissioning is planned, it is necessary to assess the safety such as exposure dose evaluation to the public. For the radioactive aerosol, it is possible that the dispersion ratio is different according to the contamination condition, the dismantlement method of the material, nuclides (elements), etc. The radiation exposure evaluation for the decommissioning plan has been executed by operators in Japan based on a number of experiments (mostly cold tests) and overseas results. The decommissioning is now being carried out at the Tokai Power Station (GCR) and Fugen Decommissioning Engineering Center in Japan. In this study, the results data is acquired at the decommissioning sites, and the methodology and data for the exposure dose evaluation are verified and confirmed. These examination results will lead to the upgrading and improvement of the exposure evaluation methodology. In particular, the dismantlement work of connected piping of the heat exchanger (steam generator) was executed in the Tokai Power Station in 2008. In this study, we paid attention to the radionuclides of Co-60 and Cs-137 that adhered to piping, and the dispersion behavior of aerosol was measured and contamination prevention effect was assured. As a result, the data show that the cesium concentrates about four times higher than cobalt. Moreover, the effects of the prevention measures of contamination were confirmed and the behavior of the radioactive aerosol became clear and the effective findings about the dose evaluation of the dismantling were collected. (authors)

  11. Observation of radioactive aerosol particle sizes in 30-km zone of the ChNPP in 1986-1987 years

    International Nuclear Information System (INIS)

    Skitovich, V.I.; Budyka, A.K.; Ogorodnikov, B.I.

    1989-01-01

    Investigation into disperse composition of radioactive aerosols was conducted in the ChNPP spaces, over ruins of 4 block, on job site and separate points of the 30-km zone by multilayer filters from ultrathin fibers. In probes taken from the job site radioactive isotopes were grouped on the particles with more than 2,5 μcm diameter. Particle sizes in the room were less than near terrestrial layer of atmosphere on job site. It is shown that the aerosol sizes containing alpha active nuclides are idential with gamma radiating isotopes of refractory elements. 4 refs., 1 fig., 2 tabs

  12. Natural and artificial radioactivity in the Svalbard glaciers

    International Nuclear Information System (INIS)

    Pinglot, J.F.; Pourchet, M.

    1994-01-01

    Natural and artificial radioactivity in the snow of 10 Svalbard glaciers has been measured from 31 ice core samples, drilled between 1981 and 1993. Of these ice cores, seven exhibit the well-known level arising from the fallout of the 1961-62 atmospheric thermonuclear tests. The second level, due to the Chernobyl accident (26 April 1986), has been detected in all the studied glaciers; the maximum 137 Cs fallout reaches 22 Bq kg -1 and shows a high variability. The natural radioactivity, mostly due to 210 Pb, shows an in-depth variation which is not governed by its half-life (22.2 years). These measurements serve many glaciological purposes: absolute dating of the snow layers; air-snow transfer and fallout studies; the determination of mean annual mass balances in the accumulation area of glaciers and their associated spatio-temporal variations. (author)

  13. Environmental pollution: influence on the operation of a sensor of radioactive aerosols; Contaminacion ambiental: influencia en el funcionamiento de un captador de aerosoles radiactivos

    Energy Technology Data Exchange (ETDEWEB)

    Duarte Rodriguez, X.; Hernandez Armas, J.; Martin Delgado, J.; Rodriguez Perestelo, N.; Perez Lopez, M.; Catalan Acosta, A.; Fernandez de Aldecoa, J. c.

    2013-07-01

    The content of radioactive aerosols in the air is an important component to estimate the ambient radiation dose. In the laboratories of environmental radioactivity, measurements of radionuclides in air they are performed using sensors. The flow picked up by the equipment can be changed if the degree of air pollution changes for some reason. It handles this study and the population doses are estimated due to inhalation of ambient air. (Author)

  14. Size distribution of natural aerosols and radioactive particles issued from radon, in marine and hardly polluted urban atmospheres

    International Nuclear Information System (INIS)

    Tymen, Georges.

    1979-03-01

    With a view to studying the natural radioactive particles produced by atttachment of 222 Rn daughters on environmental aerosol particles, the behaviours of CASELLA MK2 and ANDERSEN cascade impactors were first investigated. Their characteristic stage diameters were determined and size distributions of airborne particles were obtained in various situations. Moreover, an experimental and automatic equipment for measuring radon was devised and a method was developed in order to evaluate RaA, RaB, RaC concentrations in the free atmosphere. A degree of radioactive desequilibrium between 222 Rn and its daughters, more important than that in other locations was thus demonstrated. Furthermore, by means of various aerosol collection systems (ion tubes, diffusion batteries, cascade impactors, filters), the cumulative size distribution of natural radioactivity was established in the air, at ground level. Finally, from a theory of attachment of small radioactive ions on atmospheric particles, a tentative explanation of experimental results was made [fr

  15. 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

  16. From OLS to VIIRS, an overview of nighttime satellite aerosol retrievals using artificial light sources

    Science.gov (United States)

    Zhang, J.; Miller, S. D.; Reid, J. S.; Hyer, E. J.; McHardy, T. M.

    2015-12-01

    Compared to abundant daytime satellite-based observations of atmospheric aerosol, observations at night are relatively scarce. In particular, conventional satellite passive imaging radiometers, which offer expansive swaths of spatial coverage compared to non-scanning lidar systems, lack sensitivity to most aerosol types via the available thermal infrared bands available at night. In this talk, we make the fundamental case for the importance of nighttime aerosol information in forecast models, and the need to mitigate the existing nocturnal gap. We review early attempts at estimating nighttime aerosol optical properties using the modulation of stable artificial surface lights. Initial algorithm development using DMSP Operational Linescan System (OLS) has graduated to refined techniques based on the Suomi-NPP Visible Infrared Imaging Radiometer Suite (VIIRS) Day/Night Band (DNB). We present examples of these retrievals for selected cases and compare the results to available surface-based point-source validation data.

  17. Application of two-barrier model of radioactive agent transport in sea water for analyzing artificial radionuclide release from containers with radioactive waste dumped in Kara Sea

    Energy Technology Data Exchange (ETDEWEB)

    Grishin, Denis S.; Laykin, Andrey I.; Kuchin, Nickolay L.; Platovskikh, Yuri A. [Krylov State Research Center, Saint Petersburg, 44 Moskovskoe shosse, 196158 (Russian Federation)

    2014-07-01

    Modeling of artificial radionuclide transport in sea water is crucial for prognosis of radioecological situation in regions where dumping of radioactive waste had been made and/or accidents with nuclear submarines had taken place. Distribution of artificial radionuclides in bottom sediments can be a detector of radionuclide release from dumped or sunk objects to marine environment. Proper model can determine the dependence between radionuclide distribution in sediments and radionuclide release. Following report describes two-barrier model of radioactive agent transport in sea water. It was tested on data from 1994 - 2013 expeditions to Novaya Zemlya bays, where regular dumping of solid radioactive waste was practiced by the former USSR from the early 1960's until 1990. Two-barrier model agrees with experimental data and allows more accurate determination of time and intensity of artificial radionuclide release from dumped containers. (authors)

  18. Italian Antarctic Research Program: environmental radioactivity survey around the Italian base (1987-1991) Terra Nova Bay - Ross Sea region

    Energy Technology Data Exchange (ETDEWEB)

    Tubertini, O.; Bettoli, M.G.; Cantelli, L. [Bologna Univ. (Italy)] [and others

    1995-12-31

    Investigations have been carried out by the Italian Antartic Research Program to determine the natural and artificial radioactivity levels of both the marine and terrestrial environments. Also, natural and anthropogenic fluxes of aerosol particles onto the Antartic surface have been examined. (Author).

  19. Italian Antarctic Research Program: environmental radioactivity survey around the Italian base (1987-1991) Terra Nova Bay - Ross Sea region

    International Nuclear Information System (INIS)

    Tubertini, O.; Bettoli, M.G.; Cantelli, L.

    1995-01-01

    Investigations have been carried out by the Italian Antartic Research Program to determine the natural and artificial radioactivity levels of both the marine and terrestrial environments. Also, natural and anthropogenic fluxes of aerosol particles onto the Antartic surface have been examined. (Author)

  20. Protection of atmospheric air against radioactive gas and aerosol contaminants

    International Nuclear Information System (INIS)

    Zykova, A.S.

    1984-01-01

    Measures for contamination protection of atmospheric air subdivided into active and passive ones, are considered. The active measures envisage: development and application of waste-free flowsheets, use of flowsheets which restrict formation of gaseous-aerosol discharges; application of highly efficient treatment facilities torage. Dispersion of radioactive substances, released with discharges to the atmosphere, using high stacks; development of the corresponding site-selection solutions and arrangement of sanitary protective zones belong to passive measures. Measures for protection of atmospheric air also include waste and air contamination monitoring. The measures described are considered as applied to NPPs

  1. Experimental study of radioactive aerosols emission during the thermal degradation of organic materials in nuclear facilities

    International Nuclear Information System (INIS)

    Fernandez, Yvette

    1993-01-01

    Radioactive products may be released during a fire in nuclear fuel cycles facilities. These products must be confined to avoid a contamination spread in the environment. It is therefore necessary to be able to predict the amount and the physico-chemical forms of radioactive material that may be airborne. The aim of this study is to determine experimentally the release of contamination aerosols in a typical fire scenario involving plutonium oxide in a glove box. Firstly, this phenomenon has been studied in a small scale test chamber where samples of polymethylmethacrylate (Plexiglas) contaminated by cerium oxide (used as a substitute for plutonium oxide) were submitted to thermal degradation (pyrolysis and combustion). The release of radioactive material is determined by the quantity of contaminant emitted, the kinetics of the release and the particle size distribution of aerosols. Secondly, the development of an experimental procedure allowed to realize large scale fires in more realistic conditions. The experimental tools developed in the course of this study allow to consider application to other scenarios. (author) [fr

  2. Investigation of methods for physical characteristics of atmospheric aerosols and ground dust fractions on radioactive contaminated areas

    International Nuclear Information System (INIS)

    Artem'ev, O.I.; Osintsev, A.Yu.; Gaziev, Ya.I.; Gordeev, S.K.

    2005-01-01

    The paper presents data about current situation and trends to develop investigation methods for physical characteristics of atmospheric aerosols and ground dust fractions that are observed on the former Semipalatinsk Test Site area and adjacent regions. It was considered one of the options for comprehensive collection of radioactive aerosols as fallout within control area of atmospheric contamination and underlying surface with aerosol products of the man-caused dusting on the former STS area to determine rates of 'dry' deposition and ground-based activity concentration contained in these products of radionuclides at different distances from place of dusting. (author)

  3. Measurement of artificial radioactivity in the atmosphere at Ottawa, Canada

    Energy Technology Data Exchange (ETDEWEB)

    Terentiuk, F

    1958-01-01

    In recent years there has been considerable interest in the artificial radioactivity in the atmosphere originating from atomic and thermonuclear explosions. For the past year daily measurements of radioactivity have been made at Ottawa. The sampling times corresponded to air volumes of 425 cubic metric and 2000 cubic meters, respectively. Filters were kept for a period of 3 days before measurements were made in order to permit natural activity resulting from daughter products of radon and thoron to decay to a negligible value. Measurements of the gross beta activity from the filters were made directly with end-window Geiger tubes. Filters showing considerable initial radioactivity were measured at intervals of a few days in order to obtain the rate of decay of the activity. It was hoped that the data obtained would make it possible to fix the date of the explosion responsible for the filter activity but the fixing of dates was very uncertain.

  4. Experimental study of contamination by inhalation of radioactive iodine aerosols. Biological balance; Etude experimentale de la contamination par inhalation d'aerosols d'iode radioactif bilan biologique

    Energy Technology Data Exchange (ETDEWEB)

    Marble, G [Commissariat a l' Energie Atomique, 92 - Fontenay-aux-Roses (France). Centre d' Etudes Nucleaires

    1968-07-01

    Several articles have been published concerning research into contamination produced by inhalation of radioactive iodine aerosols in monkeys. Results dealing with the biological balance of this contamination are presented and discussed in this report. (author) [French] L'etude experimentale de la contamination par inhalation d'aerosols d'iode radioactif effectuee chez le singe a fait l'objet de plusieurs publications. Les resultats concernant le bilan biologique de cette contamination sont presentes et discutes dans ce rapport. (auteur)

  5. Artificial intelligence methods applied for quantitative analysis of natural radioactive sources

    International Nuclear Information System (INIS)

    Medhat, M.E.

    2012-01-01

    Highlights: ► Basic description of artificial neural networks. ► Natural gamma ray sources and problem of detections. ► Application of neural network for peak detection and activity determination. - Abstract: Artificial neural network (ANN) represents one of artificial intelligence methods in the field of modeling and uncertainty in different applications. The objective of the proposed work was focused to apply ANN to identify isotopes and to predict uncertainties of their activities of some natural radioactive sources. The method was tested for analyzing gamma-ray spectra emitted from natural radionuclides in soil samples detected by a high-resolution gamma-ray spectrometry based on HPGe (high purity germanium). The principle of the suggested method is described, including, relevant input parameters definition, input data scaling and networks training. It is clear that there is satisfactory agreement between obtained and predicted results using neural network.

  6. Attachment behavior of fission products to solution aerosol

    Energy Technology Data Exchange (ETDEWEB)

    Takamiya, Koichi; Tanaka, Toru; Nitta, Shinnosuke; Itosu, Satoshi; Sekimoto, Shun; Oki, Yuichi; Ohtsuki, Tsutomu [Research Reactor Institute, Kyoto University, Osaka (Japan)

    2016-12-15

    Various characteristics such as size distribution, chemical component and radioactivity have been analyzed for radioactive aerosols released from Fukushima Daiichi Nuclear Power Plant. Measured results for radioactive aerosols suggest that the potential transport medium for radioactive cesium was non-sea-salt sulfate. This result indicates that cesium isotopes would preferentially attach with sulfate compounds. In the present work the attachment behavior of fission products to aqueous solution aerosols of sodium salts has been studied using a generation system of solution aerosols and spontaneous fission source of {sup 248}Cm. Attachment ratios of fission products to the solution aerosols were compared among the aerosols generated by different solutions of sodium salt. A significant difference according as a solute of solution aerosols was found in the attachment behavior. The present results suggest the existence of chemical effects in the attachment behavior of fission products to solution aerosols.

  7. Method of monitoring volume activity of natural radioactive aerosol

    International Nuclear Information System (INIS)

    Dvorak, V.

    1980-01-01

    The method of monitoring radioactivity of a aerosol trapped, eg., with a filter is based on counting quasi-coincidences of the RaC-RaC' and ThC-ThC' decay. The first electronic unit counts quasi-coincidences at a time interval proportional to the ThC' half-life while the second electronic unit counts quasi-coincidences at a time interval proportional to the RaC' half-life, reduced by the time interval of the first electronic unit. The quasi-coincidences are evaluated of the RaC-RaC' decay independently of the ThC-ThC' quasi-coincidences and the decay products of the trapped radon and thoron gases are thus offset separately. (J.P.)

  8. Modelling of artificial radioactivity migration in environment: a survey

    International Nuclear Information System (INIS)

    Bignoli, G.; Bertozzi, G.

    1979-01-01

    The aim of this report is to present a compilation and description of models to assess the environmental behaviour and effects of accidental and routine releases of artificial radioactivity from nuclear power facilities. About 60 models are described and a card is given for each one, to indicate in summarized form its features and data content. This collection is intended to help in developing specific personal models by assembling different parts chosen among the most suitable ones of different models of various degrees of sophistication

  9. Study of filterable materials and protection instruments by the use of radioactive aerosols

    International Nuclear Information System (INIS)

    Billard; Chevalier; Pradel

    1960-01-01

    Many filtration problems can be studied by means of radioactive aerosols. For the investigations described in this paper we have chosen the solid disintegration products of radon, the radioactive gas formed from radium, because of the facilities of generation and measurement it offers. Radon and its daughters are in fact always present in the atmosphere in sufficient concentration for certain tests. In order to improve the sensitivity of the measurements, radon from uranium ore can be used. The technique of measuring by counting α particles is rapid and easy to employ. We have thus been able to define a test for filterable substances, and to check filtering installation and individual protection instruments. (author) [fr

  10. Artificial radioactivity in the environmental samples as IAEA reference materials

    International Nuclear Information System (INIS)

    Salagean, M.; Pantelica, A.

    1998-01-01

    . Uncontaminated by nuclear activities: IAEA-327, Podsolic soil collected in 1990 from the Moscow region and considered uncontaminated by radionuclides of the Chernobyl accident or by other nuclear activities. The results obtained by our laboratory are in good agreement with the certified IAEA data. Generally, the concentration of the artificial radionuclides in the investigated samples is higher than that expected from the influence of global fallout in the intercomparison materials distributed before Chernobyl accident. Concerning the nature of these investigated IAEA reference materials, very high values for the concentration levels of cesium radionuclides especially in IAEA-373 (grass) and IAEA-375 (soil) samples collected in the vicinity of Chernobyl Power Station after the nuclear accident in 1986 were found. High levels of radioactivities for the artificial radionuclides were also determined in the samples collected in the neighbourhood of the nuclear installations, especially in marine sediment (IAEA-135). It is of interest to point out the high concentration of cesium radionuclides in IAEA-300 sediment collected in 1992 in the Baltic Sea in comparison with the IAEA-306 sediment collected also in the Baltic Sea in 1986. It seems to be an increase of the Baltic Sea artificial radioactivity by accumulation in time. Marine sediment constitutes an important component of marine ecosystem since it represents the final sink for any releases of wastes into the sea. These certified radioactive materials are very useful to all laboratories engaged in the radioactive pollution investigations on environmental samples. (authors)

  11. Aerosol studies

    International Nuclear Information System (INIS)

    Cristy, G.A.; Fish, M.E.

    1978-01-01

    As part of the continuing studies of the effects of very severe reactor accidents, an effort was made to develop, test, and improve simple, effective, and inexpensive methods by which the average citizen, using only materials readily available, could protect his residence, himself, and his family from injury by toxic aerosols. The methods for protection against radioactive aerosols should be equally effective against a clandestine biological attack by terrorists. The results of the tests to date are limited to showing that spores of the harmless bacterium, bacillus globegii (BG), can be used as a simulant for the radioactive aerosols. An aerosol generator of Lauterbach type was developed which will produce an essentially monodisperse aerosol at the rate of 10 9 spores/min. Analytical techniques have been established which give reproducible results. Preliminary field tests have been conducted to check out the components of the system. Preliminary tests of protective devices, such as ordinary vacuum sweepers, have given protection factors of over 1000

  12. Study of radioactive aerosols emissions and establishment of a model in a nuclear medicine environment during the use of a technetium generator

    International Nuclear Information System (INIS)

    Bombardier, Pierre

    2012-01-01

    This work deals with the control of radioactive aerosols emissions inside the nuclear medicine facilities. These emissions occur during pulmonary scintigraphy examinations using aerosols marked with 99m Tc. Using a test chamber, we have developed a method permitting to quantify these emissions around the aerosol generator. A method dedicated to emissions measurement coming from the patient during the pulmonary ventilation is also described. The results obtained on one patient are exposed in this thesis. We characterized and modelled the ventilation of a complete nuclear medicine department with a CFD (Computational Fluid Dynamics) software. This permitted us to study the dissemination of the radioactive aerosol and to compare it with measures of ambient air activity. The numerical model of this department was then employed to test containment solutions and to help defining the best location for air contaminations sensors. An original method combining staff position information and the simulation of the dissemination for the aerosol released has been used to confirm the exposure levels for several professional groups and enhance the workplace studies. (author)

  13. Aerosol science: theory and practice

    International Nuclear Information System (INIS)

    Williams, M.M.R.; Loyalka, S.K.

    1991-01-01

    The purpose of this book is twofold. First, it is intended to give a thorough treatment of the fundamentals of aerosol behavior with rigorous proofs and detailed derivations of the basic equations and removal mechanisms. Second, it is intended to provide practical examples with special attention to radioactive particles and their distribution in size following a radioactive release arising from an accident with a nuclear system. We start with a brief introduction to the applications of aerosol science and the characteristics of aerosols in Chapter 1. In Chapter 2, we devote considerable attention to single and two particle motion with respect to both translation and rotation. Chapter 3 contains extensive discussion of the aerosol general dynamical equation and the dependences of aerosol distributions on size, shape, space, composition, radioactivity, and charge. Important particle rate processes of coagulation, condensation, and deposition/resuspension are discussed in the chapters 4, 6 and 7, respectively. In Chapter 5, we provide a thorough treatment of the analytical and numerical methods used in solving the various forms of the aerosol dynamical equation. We discuss the importance and applications of aerosol science to nuclear technology and, in particular, the nuclear source term in Chapter 8. Our focus in this chapter is on discussions of nuclear accidents that can potentially release large amount of radioactivity to environment. We also discuss the progress that has been made in understanding the natural and engineered aerosol processes that limit or affect such releases. (author)

  14. Natural and artificial radioactivity in Great Bratislava

    International Nuclear Information System (INIS)

    Lanc, J.

    1997-01-01

    The results of the aviation measurement of the gamma-radiation are presented in the form of the maps of iso-lines of the concentration of the natural radioactive elements (potassium, uranium, thorium) and artificial radionuclides (cesium-137, cesium-134). From the obtained dates the maps of dose rate of the gamma-radiation in the air are calculated, of the dose equivalent rate and the map of the fraction of the dose equivalent rate from the natural elements potassium, uranium, thorium. The natural radioactivity of the minerals in the Great Bratislava region, especially for the extreme low values of the contain of the thorium, does not amount the average values of the radioactivity of the Earth crust. The area activity of cesium-137 are in the range 2 - 10 kBq.m -2 and cesium-134 is 1 - 2.5 kBq.m -2 . From the point of view of the summary level of the external irradiation from the Earth surface the measured zone as relative even is evaluated, in the range 10-100 nSv.h -1 . The total average level of the dose rate of the external irradiation of man (inclusively from the cosmic radiation 40-50 nSv.h -1 ) in the conditions of Bratislava is 100 nSv.h -1 . The contribution of external component of the irradiation is 40-100 nSv.h -1 (0.1-0.3 mSv.y -1 ). The dose equivalent commitment of internal component from the cesium-137 is for the all age category of the population under the level negligible risk 0.01 mSv.y -1 [sk

  15. Experimental study of contamination by inhalation of radioactive iodine aerosols. Biological balance; Etude experimentale de la contamination par inhalation d'aerosols d'iode radioactif bilan biologique

    Energy Technology Data Exchange (ETDEWEB)

    Marble, G. [Commissariat a l' Energie Atomique, 92 - Fontenay-aux-Roses (France). Centre d' Etudes Nucleaires

    1968-07-01

    Several articles have been published concerning research into contamination produced by inhalation of radioactive iodine aerosols in monkeys. Results dealing with the biological balance of this contamination are presented and discussed in this report. (author) [French] L'etude experimentale de la contamination par inhalation d'aerosols d'iode radioactif effectuee chez le singe a fait l'objet de plusieurs publications. Les resultats concernant le bilan biologique de cette contamination sont presentes et discutes dans ce rapport. (auteur)

  16. Aerosol-foam interaction experiments

    International Nuclear Information System (INIS)

    Ball, M.H.E.; Luscombe, C.DeM.; Mitchell, J.P.

    1990-03-01

    Foam treatment offers the potential to clean gas streams containing radioactive particles. A large decontamination factor has been claimed for the removal of airborne plutonium dust when spraying a commercially available foam on the walls and horizontal surfaces of an alpha-active room. Experiments have been designed and undertaken to reproduce these conditions with a non-radioactive simulant aerosol. Careful measurements of aerosol concentrations with and without foam treatment failed to provide convincing evidence to support the earlier observation. The foam may not have been as well mixed with the aerosol in the present studies. Further work is required to explore more efficient mixing methods, including systems in which the aerosol steam is passed through the foam, rather than merely spraying foam into the path of the aerosol. (author)

  17. The use of an experimental device for the determination of the concentration of artificial radioactive aerosols at high altitudes; Utilisation d'un missile experimental pour l'evaluation des concentrations en aerosols radioactifs artificiels en haute altitude

    Energy Technology Data Exchange (ETDEWEB)

    Boclet, D; Jehanno, C; Labeyrie, J [Commissariat a l' Energie Atomique, Saclay (France).Centre d' Etudes Nucleaires; Le Boiteux, H [Office National d' Etudes et de Recherches Aeronautique, 92 - Chatillon sous Bagneux (France)

    1960-07-01

    By means of measurements with a Geiger counter on january, the 27{sup th}, in 1959 at an altitude reaching 65 km approximately, and following comparison with similar measurements made by Gangnes, Jenkins and Van Allen in 1949 at the same geomagnetic latitude (41 deg. North), it is concluded that radioactive aerosols above Southern France tropopause had a concentration less than 100.10{sup -12} curies/m{sup 3} at that time. The missile used for this purpose and its performance are quickly described in this paper. (author) [French] Au moyen de mesures faites au compteur Geiger le 27 janvier 1959 jusqu'au environ de 65 km et apres comparaison avec des mesures analogues faites en 1949 par Gangnes, Jenkins et Van Allen a la meme altitude geomagnetique (41deg. N), on conclut que les aerosols radioactifs au-dessus de la tropopause de la France meridionale avaient a cette epoque une concentration inferieure a 100.10{sup -12} curies/m{sup 3}. Une rapide description du missile utilise et de ses performances complete cette communication. (auteur)

  18. A new method for measuring aerosol nebulizers output using radioactive tracers

    International Nuclear Information System (INIS)

    Gatnash, A.A.; Connolly, C.K.; Chandler, S.T.

    1998-01-01

    Reproducibility and comparability of bronchial challenge tests depends critically on accurate assessment of nebulizers output. Evaporation during nebulization means that simple weighing is inaccurate, overestimating the delivered dose of active ingredient. We wanted to quantify this effect in the context of intermittent nebulization, using a dosimeter as used in bronchial provocation tests. Output of three types of nebulizers, from the MEFAR dosimeter, was measured by radioactive tracer, using a standard solution of technetium-99m-pertechnetate (1.5 kBq x mL -1 ) in 4 mL of normal saline. The aerosol was impacted by suction onto a micro filter, and the radioactivity measured. Nebulizers were weighed before and after nebulization. Ratio of nebulized volume calculated from the radioactivity on the filter, to the total volume loss by weight, was expressed as nebulized ratio. The effect on output of two concentrations of methacholine, two tracers of different weights, and change in temperature, were assessed. Nebulized ratio varied between 44.1-71.6%. Results were more consistent within the same type of nebulizer than between different makes. Neither changes in molar concentration nor molecular weight affected nebulizer output or nebulized ratio. Mean nebulized ratio was 58.5%, showing that calibration by weighing, overestimates the delivered dose by a factor of approximately two. Measuring radioactivity eluted from a micro filter, onto which nebulized output had been impacted proved to be a satisfactory method of calibration. (au)

  19. Control method of air activity levels by the presence of radioactive aerosol

    International Nuclear Information System (INIS)

    Cornejo D, N.; Alonso J, M.T.; Zerquera, J.T.; Barroso P, I.

    1996-01-01

    The filtration of great air volumes and further measurement of suitable filter gross beta activity have been the method used by The National Radiological Environmental Monitoring Network of the Republic of Cuba in order to asses, quantitatively, the beta activity in air. The values measured by the three aerosol monitoring laboratories in the country show that the volumetric activity of short-lived radionuclides varied from 0.62 to 6.9 Bq/m 3 . The gross activity values, due to the presence of long-lived radionuclides in air have not been higher than the detection limit of 4 mBq/m 3 . The annual effective dose estimation due to the inhalation of radioactive aerosol from natural sources ranged from 0.03 to 0.3 mSv. These values were lower than the world-wide mean dose (0.80 mSv) and were related to the features of our natural environment. (authors). 6 refs., 1 tab

  20. Equipment for the continuous measurement and identification of gamma radioactivity on aerosols

    Energy Technology Data Exchange (ETDEWEB)

    De Blas, Alfredo; Tapia, Carlos; Riego, Albert; Garcia, Roger; Dies, Javier; Diaz, Pedro [Nuclear Engineering Research Group, Departament of Physics and Nuclear Engineering, Technical University of Catalonia, Barcelona (Spain); Toral, Juan [Raditel Serveis. Tarragona (Spain); Batalla, Enric [Radiological Activities Corrdination Service - SCAR, Generalitat de Catalunya, Barcelona (Spain)

    2015-07-01

    Presentation the Equipment for the Continuous Measurement and Identification of Gamma Radioactivity on Aerosols developed by the Nuclear Engineering Research Group (NERG) from the Technical University of Catalonia (UPC) and the Raditel Company. The device is based on a fixed filter of glass fiber (100% borosilicate), this allows determine the concentration of activity of gamma emitters on aerosols in air. A specifically developed Spectrometry Analysis System has been developed. The analysis of the spectra allows the identification of the emitters and determine the concentration of activity. Nowadays four Stations with this equipment are operating on the Environmental Radiological Surveillance Network of the Catalonian Generalitat (Spain): two near the Asco and Vandellos Nuclear Power Plants in the province of Tarragona and one in the city of Barcelona. Soon a fourth monitor will be incorporated at Roses (province of Girona) and a fifth in Puigcerda (province of Barcelona). We present measurements and analysis of the evolution of the emitters identified on different stations of the Network. (authors)

  1. Respiratory clearance of aerosolized radioactive solutes of varying molecular weight

    International Nuclear Information System (INIS)

    Huchon, G.J.; Montgomery, A.B.; Lipavsky, A.; Hoeffel, J.M.; Murray, J.F.

    1987-01-01

    To determine the influence of varying molecular weight (mol wt) on respiratory clearance of aerosolized solutes, we studied eight radiopharmaceuticals, each administered to four dogs: sodium /sup 99m/Tc pertechnetate (TcO4), /sup 99m/Tc glucoheptonate ([/sup 99m/Tc]GH), 51Cr-ethylenedinitrotetraacetate ([51Cr]EDTA), /sup 99m/Tc diethylenetriaminepentaacetate ([99mTc] DTPA), 111 In diethylenetriaminepentaacetate ([ 111 In]DTPA), 67 Ga desferoxaminemesylate ([ 67 Ga]DFOM), /sup 99m/Tc dextran ([/sup 99m/Tc]DX) and 111 In transferrin ([ 111 In]TF). After aerosolization (0.8 m MMD, 2.4 GSD), clearance was determined for 30 min and then corrected by intravenous injection for nonairspace radioactivity. In-TF clearance (0.11 +/- 0.10%/min) was lower than TcO4 (6.32 +/- 0.62%/min), [/sup 99m/Tc]GH (1.50 +/- 0.37%/min), [ 51 Cr]EDTA (2.38 +/- 1.02%/min), [/sup 99m/Tc]DTPA (3.51 +/- 0.40%/min), [ 111 In]DTPA (2.35 +/- 0.42%/min), [ 67 Ga] DFOM (1.99 +/- 0.49%/min) and [/sup 99m/Tc]DX (1.81 +/- 0.75%/min) clearances (p less than 0.001). TcO4 clearance was higher than others (p less than 0.001). Technetium binding to DX was unsatisfactory; aerosolization caused unbinding from DTPA. We conclude that respiratory clearance of large mol wt solutes within 30 min is negligible and, that clearance of molecules between 347-5099 daltons differs greatly, suggesting that binding and/or intrapulmonary retention affect transfer

  2. Aerosol measurements and nuclear accidents: a reconsideration

    International Nuclear Information System (INIS)

    Raes, F.

    1988-01-01

    Within its radioactivity environmental monitoring programme, the Commission of the European Communities and in particular its Joint Research Centre wants to encourage the qualitative improvement of radioactivity monitoring. On 3 and 4 December 1987 an experts' meeting has been organized by the Ispra Joint Research Centre in collaboration with the Gesellschaft fuer Aerosolforschung, in order to discuss measuring techniques for radioactive aerosols in the environment in case of a nuclear accident. During the workshop, current practices in routine monitoring programmes in the near and far field of nuclear power plants were confronted with the latest developments in the metrology of aerosols and radioactivity. The need and feasibility of implementing advanced aerosol and radioactivity techniques in routine monitoring networks have been discussed. This publication gives the full text of 12 presentations and a report of the roundtable discussion being held afterwards. It does not intend to give a complete picture of all activities going on in the field of radioactive aerosol metrology; it rather collects a number of common statements of people who approach the problem from quite different directions

  3. Aerosols and the lungs

    International Nuclear Information System (INIS)

    1987-01-01

    The lectures of the colloquium are discussed in summary form. There were 5 lectures on aerosol deposition, 5 on aerosol elimination, 7 on toxicology, and 7 on the uses of aerosols in medical therapy. In some cases aerosols with radioactive labels were used. Several lectures reviewed the kinetics and toxicology of airborne environmental pollutants. (MG) [de

  4. High capacity Venturi scrubber to separate aerosol-borne radioactivity from an air-gas-steam mixture. Final report

    International Nuclear Information System (INIS)

    Mayinger, F.; Glueckert, U.

    1993-01-01

    All German LWR are equipped with devices which in the case of a hypothetic accident permit a filtered depressurization of the containment precluding failure of the latter and minimizing the release of radioactive materials into the environment. To filter the aerosol charged air-steam mixture from the containment also a venturi scrubber is used. It has the great advantage that it can remove safely and over a certain period of time, even without active cooling systems, the after-heat released from the separated radioactive materials. Those separated radioactive materials are trapped in a scrubbing liquid which, in the event of a temporary failure of all active cooling systems, may partly evaporate and thus remove the heat in a completely passive way. The venturi scrubbers conceived earlier by the reactor manufacturer are of a very simple design and not optimized to achieve highest separation degrees. Therefore development work was started to optimize the separation behaviour of the venturi scrubber precisely with regard to submicron aerosols which are to be expected after a core meltdown accident. To achieve this, a special concept of scrubbing liquid addition developed by the contractor, the so-called multistage concept, was applied adapting it to the specific requirements. (orig./HP) [de

  5. Trace elements and radioactivity in aerosol particles, produced in the area of Ptolemais (Greece)

    International Nuclear Information System (INIS)

    Kallithrakas-Kontos, N.; Zoumi, K.; Nikolakaki, S.; Kritidis, P.

    1998-01-01

    Most of the Greek lignite power plants have been installed in the area of Ptolemais, and a major part of them during the period 1981-1990. Aerosol filters collected in the first and the last years of the decade have been analysed for trace elements as well as for radioactivity (total beta) content. Analysis was performed by radioisotope excited X-ray fluorescence, and 17 elements were determined. A special interest is focused on lead concentrations, an element whose environmental concentrations are regulated by the Greek law; the results for lead were validated by atomic absorption spectrometry. Trace element and radioactivity levels were found significantly lower than the current limit. Enrichment factors and correlation among the analysed elements were also estimated. (author)

  6. Comparison of radioactivity data measured in PM10 aerosol samples at two elevated stations in northern Italy during the Fukushima event.

    Science.gov (United States)

    Tositti, Laura; Brattich, Erika; Cinelli, Giorgia; Previti, Alberto; Mostacci, Domiziano

    2012-12-01

    The follow-up of Fukushima radioactive plume resulting from the 11th March 2011 devastating tsunami is discussed for two Italian stations in the northern Apennines: Mt. Cimone (Modena) and Montecuccolino (Bologna). Radioactivity data collected at both stations are described, including comparison between local natural background of airborne particulate and artificial radioactivity referable to the arrival of the radioactive plume and its persistence and evolution. Analysis of back-trajectories was used to confirm the arrival of artificial radionuclides following atmospheric transport and processing. The Fukushima plume was first detected on 3rd April 2011 when high volume sampling revealed the presence of the artificial radionuclides (131)I, (137)Cs and (134)Cs. The highest activity concentrations of these nuclides were detected on 5th April 2011 at the Montecuccolino site. Fukushima radioactivity data at the two stations were usually comparable, suggesting a good vertical mixing of the plume; discrepancies were occasional and attributed to different occurrence of wet removal, typically characterized by a scattered spatial pattern. To understand the relevance to the local population of the extra dose due to the Fukushima plume, atmospheric activities of the related artificial nuclides were compared to those of the main natural radionuclides in ambient particulate, and found to be lower by over one order of magnitude. Radiation doses referable to Fukushima, maximized for a whole year occurrence at the highest activity level observed at our stations in the weeks affected by the Japanese plume, were estimated at 1.1 μSv/year. Copyright © 2012 Elsevier Ltd. All rights reserved.

  7. Monitoring of the radioactivity in the aerosols at Moussala and some regions in Bulgaria

    International Nuclear Information System (INIS)

    Penev, I.; Damyanov, B.; Ivanov, P.

    2004-01-01

    The subject of the study in this article is monitoring of the natural and industrial radioactivity in the aerosols, including some heavy elements. It is interesting to clear up the behavior of some isotopes, like 7 Be and 210 Pb during the years at different altitude and places, in industrial area and in area free from all kind pollution's, like Rila National Park. This data is compared with the presence of heavy elements, like Pb, Fe, Cd and others. For collecting of the aerosols are used 3 different air-flow devices with capacity from 80m 3 to 1500m 3 . For gamma-analysis are used scintillation NaI, GeLi and HPGe spectrometers. Heavy elements are analyzed with X-ray spectrometer. All spectrometers could be used in the case of unexpected industrial or military pollutions. (authors)

  8. Medical imaging was boosted by the discovery of artificial radioactivity

    International Nuclear Information System (INIS)

    Demarthon, F.; Dupuy-Maury, F.; Donnars, O.

    2002-01-01

    This article draws the history of medical imaging since the discovery of artificial radioactivity in 1934. The author reviews the PET (positron emission tomography) and MRI (magnetic resonance imaging) technologies and presents the recent progress in neuro-sciences that have been made possible by using these 2 technologies. Brain imaging has allowed to show: - the impact of emotions on logical mental processes and on mental performances, - the management of memory in the brain of talented quick reckoners, - the degeneration of neurons, and - the link between autism and the presence of structural and functional anomalies in the brain. (A.C.)

  9. Study of uranium mine aerosols

    International Nuclear Information System (INIS)

    Barzic, J.-Y.

    1976-05-01

    With a view to radiation protection of uranium-miners a study was made of the behaviour of radioactive and non-radioactive aerosols in the atmosphere of an experimental mine where temperature, pressure, relative himidity and ventilation are kept constant and in the air of a working area where the nature of the aerosol is dependent on the stage of work. Measurements of radon and daughter products carried out in various points of working areas showed that the gas was quickly diluted, equilibrium between radon and its daughter products (RaA, RaB, RaC) was never reached and the radon-aerosol contact was of short duration (a few minutes). Using a seven-stage Andersen impactor particle size distribution of the mine aerosol (particle diameter >0.3μm) was studied. The characteristic diameters were determined for each stage of the Andersen impactor and statistical analysis verified that aerosol distributions on the lower stages of the impactor were log-normal in most cases. Finally, determination of size distribution of α-radioactivity showed it was retained on fine particles. The percentage of free α-activity was evaluated using a diffusion battery [fr

  10. Processing methods for operation test data of radioactive aerosols monitor based on accumulation techniques

    International Nuclear Information System (INIS)

    Fu Cuiming; Xi Pingping; Ma Yinghao; Tan Linglong; Shen Fu

    2011-01-01

    This article introduces a radioactive aerosol continuous monitor based on accumulation sampling and measuring and three methods for processing the operation data. The monitoring results are processed by the 3 methods which are applied both under the conditions of natural background and at workplaces of a nuclear facility. How the monitoring results are assessed and how to calculate the detection limit when using the 3 different methods are explained. Moreover, the advantages and disadvantages of the 3 methods are discussed. (authors)

  11. Atmospheric natural radioactivity outdoors

    International Nuclear Information System (INIS)

    Renoux, A.

    1985-01-01

    Following a short account of natural atmospheric radioactivity, radon concentrations are given as well as their variations with time obtained by means of a original apparatus developped in Brest. The radioactive equilibrium of radon and its daughters is then considered, many experiments demonstrating that equilibrium is seldom reached even for 218 Po (RaA). Finally, some characteristics of natural radioactive aerosols are studied: charge, particle size distribution (demonstrating they are fine aerosols since only 30 per cent are made of particles with radii exceeding 0,1 μm) [fr

  12. Enrico Fermi's Discovery of Neutron-Induced Artificial Radioactivity:The Recovery of His First Laboratory Notebook

    Science.gov (United States)

    Acocella, Giovanni; Guerra, Francesco; Robotti, Nadia

    . We give a short description of the discovery of the first experimental notebook of Enrico Fermi (1901-1954) on his researches during March and April of 1934 on neutron-induced artificial radioactivity, and we point out its relevance for a proper historical and conceptual understanding of those researches.

  13. A radioactive aerosols in air monitoring system - 'ASIA'

    International Nuclear Information System (INIS)

    Belaish, I.; Levinson, S.; Pelled, O.; German, U.; Laichter, Y.; Gonen, E.; Wengrowicz, U.; Tirosh, D.; Barak, D.

    1997-01-01

    A continuous air monitoring system called 'ASIA' (Aerosols Sampler In Air) was developed at the NRCN for monitoring and measuring the concentration of airborne alpha emitting radionuclides such as Radon or natural Uranium. The 'ASIA' is a stationary multi-channel analyzer based system. The air passes through a 2.5 cm diameter filter and the radioactivity accumulated on it is monitored by a Silicon solid state detector. The sampling unit can be separated from the display and control unit to enable environment sampling close to the workers. The ASIA uses modern hardware and software in order to improve noise and background reduction and to allow friendly and flexible use. Remote communication is also available. The spectrum and additional data are displayed on line. The system was checked according to ANSI N42.17B -1989. The linearity and efficiency were evaluated by using various alpha sources. The Minimum Detectable Activity (MDA) and Decision Limit (Lc) were calculated according to ANSI N13.30. Long time stability measurements were performed using a natural Uranium source. (authors)

  14. Artificial radioactivity on the coasts of Northern Ireland

    International Nuclear Information System (INIS)

    Garland, J.A.; McKay, W.A.; Burton, P.J.; Cambray, R.S.

    1989-01-01

    In Northern Ireland, measurements of artificial radioactivity have been made in inshore seawater, beach sand and mud, sea spray, the air and material deposited from the air, and in coastal soil. The objective was to determine the levels in the coastal environment and also to assess the magnitude of transport of radioactivity from sea to land in sea spray. The results would provide a basis for the development of a model describing sea to land transfer, and allowing the resulting population exposure to be assessed. The results showed the presence of plutonium isotopes, 241 Am and 137 Cs in some samples of each of the media measured, but concentrations were low in all cases. Large variation in the concentrations in seawater and beach sediment were attributed to variations in dispersion and in the characteristics of the sediment. Sea to land transfer of actinides was detected in samples of sea spray and in air and deposition measurements. Only at some sites on the east coast could the resulting accumulation in soil close to the beach be distinguished from fallout. Following May 1986 137 Cs from Chernobyl could be detected in air and in atmospheric deposition. A preliminary assessment of the exposure of the population to the actinides and 137 Cs in all the media showed that the resulting dose is a small fraction of the recognised limit. (author)

  15. Natural and artificial radioactivity determination of some medicinal plants

    International Nuclear Information System (INIS)

    Desideri, Donatella; Meli, Maria Assunta; Roselli, Carla

    2010-01-01

    Several medicinal plants used in Italy were analysed to determine natural and artificial radioactivity in those parts (leaves, fruits, seeds, roots, peduncles, flowers, barks, berries, thallus) used generally as remedies. The radionuclides were determined by alpha ( 238 U, 210 Po) and gamma ( 214 Pb-Bi, 210 Pb, 40 K and 137 Cs) spectrometry. 238 U ranged between dry -1 ; 210 Po between dry -1 ; 214 Pb- 214 Bi between dry -1 ; 210 Pb between dry -1 ; 40 K between 66.2 and 3582.0 Bq kg dry -1 ; 137 Cs between dry -1 . The percentage of 210 Po extraction in infusion and decoction was also determined; the arithmetical mean value of percentage of 210 Po extraction resulted 20.7 ± 7.5.

  16. Comparative levels of radioactive air pollutants from industry and fallout. A progress report of radioecological investigations of airborne radioactivity in the Utah environment

    International Nuclear Information System (INIS)

    Pendleton, R.C.

    1972-01-01

    Results are reported of measurements carried on during the year 1971 and the first two months of 1972 on the radioactivity from natural as compared to artificial radiation sources in the environment in Utah. During this time, a major portion of our work was devoted to analyses of the data and preparation of a report related to the Baneberry venting event and the accumulation of data on fallout from the January 7, 1972 Chinese nuclear explosion. Calibration procedures were developed for air samplers for the establishment of the numbers of pCi/m 3 in air. The responses of the air monitors in relationship to the ventilation index, seasonal effect, and the industrial complexity of the area were analyzed. Continuous measurements were made of the levels of radioactive materials in soils and vegetation and the results of these studies are presented mainly in tabular form. Comparisons have been made of the levels of radioactive materials in soils on the basis of square mile levels and the distribution of the radioactive materials in the soil profiles. Measurements of farm crops, including the major sources from which dairy products would be produced, have been made, and some comparisons by year and location have been made. Studies of secondary aerosols have been made using the dust accumulated on farm implements as the indicator of the kinds of secondary aerosols to which farmers and outdoorsmen might be exposed. These results would also be indicative of the kinds of dusts produced when high winds resuspend soil deposited radionuclides

  17. Artificial neural network application in isotopic characterization of radioactive waste drums

    International Nuclear Information System (INIS)

    Potiens Junior, Ademar Jose

    2005-01-01

    One of the most important aspects to the development of the nuclear technology is the safe management of the radioactive waste arising from several stages of the nuclear fuel cycles, as well as from production and use of radioisotope in the medicine, industry and research centers. The accurate characterization of this waste is not a simple task, given to its diversity in isotopic composition and non homogeneity in the space distribution and mass density. In this work it was developed a methodology for quantification and localization of radionuclides not non homogeneously distributed in a 200 liters drum based in the Monte Carlo Method and Artificial Neural Network (RNA), for application in the isotopic characterization of the stored radioactive waste at IPEN. Theoretical arrangements had been constructed involving the division of the radioactive waste drum in some units or cells and some possible configurations of source intensities. Beyond the determination of the detection positions, the respective detection efficiencies for each position in function of each cell of the drum had been obtained. After the construction and the training of the RNA's for each developed theoretical arrangement, the validation of the method were carried out for the two arrangements that had presented the best performance. The results obtained show that the methodology developed in this study could be an effective tool for isotopic characterization of radioactive wastes contained in many kind of packages. (author)

  18. Aerosols CFA 97

    International Nuclear Information System (INIS)

    Anon.

    1998-01-01

    During the thirteen congress on aerosols several papers were presented about the behaviour of radioactive aerosols and their impact on environment, or the exposure to radon and to its daughters, the measurement of the size of the particulates of the short-lived radon daughters and two papers about the behaviour of aerosols in containment during a fission products release in the primary circuit and susceptible to be released in atmosphere in the case of containment failure. (N.C.)

  19. Composition of Radioactive Aerosols in the Shelter Construction of the Chernobyl Nuclear Power Plant in 2000-2015

    Science.gov (United States)

    Ogorodnikov, B. I.

    2018-06-01

    The results of the physicochemical studies of radioactive aerosols inside and outside the Shelter construction at the Arch construction stage of the Chernobyl Nuclear Power Plant (ChNPP) in 2000-2015 were presented. The dominant isotopes were shown to be cesium, strontium, americium, plutonium, and uranium. They are carried by disperse particles of 2-7 μm. In subreactor rooms, in particular, 012/7, the composition of aerosols is affected by the erosion of the fuel-containing mass formed in 1986. Submicron cesium carrier aerosols appear as a result of evaporation and condensation during fires and welding works. Radiocesium is a well-soluble component of aerosols, while plutonium isotopes are not readily soluble components. In several rooms, the contents of radon, thoron, and their daughter products exceeded the permissible values. In April-June 2011, the intake of radionuclides from the accident at the Japanese Fukushima-1 NPP, which had AMAD of 0.5 μm, was detected and tracked using Petryanov multilayer filters. The productivity of filtration units under the dusty conditions in the exclusion zone of ChNPP and in fogs and haze was investigated. Hydrophilic prefilters with 7-10 μm fibers were recommended.

  20. Lung Deposition Calculations for Radioactive Aerosol Particles Originating from Caves and Uranium Mines

    International Nuclear Information System (INIS)

    Alfoldy, B.; Torok, Sz.; Winkler, R.

    2001-01-01

    Full text: The present study simulates lung deposition of radioactive aerosol particles originating from the atmosphere of a therapeutic cave (Szemlohegyi cave, Budapest) and several uranium mines. Particle deposition patterns and surface densities have been calculated by the stochastic lung model of Koblinger and Hofmann. In the model, deposition can be caused by the simultaneous effects of Brownian motion, inertial impaction and gravitational settling. The calculations were carried out by considering the aerosol particle size distribution and radon concentration of the atmosphere of the cave and mines. The deposition was computed in the whole lung, in characteristic parts of the respiratory system such as extrathoracic, tracheobronchial, acinar and alveolar regions and in the singe airway generations at different flow rates for adults. The adverse health effects of inhaled radionuclides strongly depend from the local deposition density values in cellular dimensions. Thus we will built in the results to a cellular effects model of Balashazy and Hofmann for the simulation of the pathological effects of inhaled radionuclides for risk assessment. (author)

  1. Quantitative evaluation of inhaled radioactive aerosol deposition patterns in the lungs in obstructive airways disease

    Energy Technology Data Exchange (ETDEWEB)

    Teshima, Takeo; Isawa, Toyoharu; Hirano, Tomio; Ebina, Akio; Shiraishi, Koichiro; Konno, Kiyoshi

    1985-12-01

    Uneven distribution of inhaled aerosol in the lungs is the characteristics of obstructive airways disease such as chronic bronchitis and pulmonary emphysema, and has been classified typically into peripheral and central deposition patterns, respectively by visual inspection, whereas in the normal the distribution is homogeneous throughout the lungs. The purpose of the present study was to analyse the distribution of inhaled radioactivity in the lungs by way of matrixes by a computer. The seemingly homogeneous distribution pattern in normal subjects has been found to indicate a gradual change in count profile between the neighboring matrixes. The peripheral pattern indicates the patchy presence of small number of matrixes with excessive radioactivity throughout the lungs, and the central pattern, the presence of matrixes of excessive radioactivity along the major central airways forming a comma-like configuration superimposed on the peripheral pattern. Our computer analysis has a potentiality to characterize obstructive airways disease for a better understanding of their pathophysiology, which is not feasible by a simple visual inspection of images on a polaroid picture.

  2. Special aerosol sources for certification and test of aerosol radiometers

    International Nuclear Information System (INIS)

    Belkina, S.K.; Zalmanzon, Y.E.; Kuznetsov, Y.V.; Rizin, A.I.; Fertman, D.E.

    1991-01-01

    The results are presented of the development and practical application of new radionuclide source types (Special Aerosol Sources (SAS)), that meet the international standard recommendations, which are used for certification and test of aerosol radiometers (monitors) using model aerosols of plutonium-239, strontium-yttrium-90 or uranium of natural isotope composition and certified against Union of Soviet Socialist Republics USSR national radioactive aerosol standard or by means of a reference radiometer. The original technology for source production allows the particular features of sampling to be taken into account as well as geometry and conditions of radionuclides radiation registration in the sample for the given type of radiometer. (author)

  3. Special aerosol sources for certification and test of aerosol radiometers

    Energy Technology Data Exchange (ETDEWEB)

    Belkina, S.K.; Zalmanzon, Y.E.; Kuznetsov, Y.V.; Rizin, A.I.; Fertman, D.E. (Union Research Institute of Instrumentation, Moscow (USSR))

    1991-01-01

    The results are presented of the development and practical application of new radionuclide source types (Special Aerosol Sources (SAS)), that meet the international standard recommendations, which are used for certification and test of aerosol radiometers (monitors) using model aerosols of plutonium-239, strontium-yttrium-90 or uranium of natural isotope composition and certified against Union of Soviet Socialist Republics USSR national radioactive aerosol standard or by means of a reference radiometer. The original technology for source production allows the particular features of sampling to be taken into account as well as geometry and conditions of radionuclides radiation registration in the sample for the given type of radiometer. (author).

  4. Finish-Kazakhstan cooperation on an aerosols sampling - testing of a new methods for nuclear monitoring improvement

    International Nuclear Information System (INIS)

    Tarvajnen, M.; Akhmetov, M.A.; Ptitskaya, L.D.; Osintsev, A.Yu.; Zhantikin, T.M.; Eligbaeva, G.

    2001-01-01

    The aerosols sampling is the powerful method of air radioactivity monitoring both the natural and artificial origin. Up to the today the IAEA does not engage of aerosols sampling study. To study of possibility of this method examination for radiation monitoring - the state authorities of Finland and the Republic of Kazakhstan - Department of Radiation and Nuclear Safety (Stuck) and Kazakhstan Atomic Energy Committee - jointly carried out the field tests in Kazakhstan. The test was began in the Kurchatov in April 2000 - at the desire of IAEA working team on Iraq - close to former Semipalatinsk test site and was ended in Astana in August of 2001. The main aim of the field test was study of possibility and appropriateness of concept and technology of aerosols sampling developed for the complete condition of environment. In the paper the role of participating sides in the field test and main results and conclusions are discussed as well. The gained experience will allow developing the method aerosols sampling for IAEA international safeguard measures strengthening application

  5. Environmental radioactivity measurements in greece following the Fukushima Daichi nuclear accident

    International Nuclear Information System (INIS)

    Potiriadis, C.; Kolovou, M.; Clouvas, A.; Xanthos, S.

    2008-01-01

    Since the double disaster of the 9.0 magnitude earthquake and tsunami that affected hundreds of thousands of people and seriously damaged the Fukushima Daichi power plant in Japan on 11 March 2011, traces of radioactive emissions from Fukushima have spread across the entire northern hemisphere. The radioactive isotope of iodine 131 I that was generated by the nuclear accident in Fukushima arrived in Greece on 24 March 2011. Radioactive iodine is present in the air either as gas or bound to particles (aerosols). The maximum 131 I concentrations were measured between 3 and 5 April 2011. In aerosols the maximum 131 I values measured in Southern Greece (Athens) and Northern Greece (Thessaloniki) were 585±70 and 408±61 μBq m -3 , respectively 131 I concentrations in gas were about 3.5 times higher than in aerosols. Since 29 April 2011, the 131 I concentration has been below detection limits. Traces of 137 Cs and 134 Cs were also measured in the air filters with an activity ratio of 137 Cs/ 134 Cs equal to 1 and 131 I/ 137 Cs activity ratio of about 3. Since 16 May 2011, the 137 Cs concentration in air has been determined to be about the same as before the Fukushima accident. Traces of 131 I were also measured in grass and milk. The maximum measured activity of 131 I in sheep milk was about 2 Bq l -1 which is 5000 times less than that measured in Greece immediately after the Chernobyl accident. The measured activity concentrations of artificial radionuclides in Greece due to the Fukushima release, have been very low, with no impact on human health. (authors)

  6. Using radioactivity

    International Nuclear Information System (INIS)

    1982-10-01

    The leaflet discusses the following: radioactivity; radioisotopes; uses of ionising radiations; radioactivity from (a) naturally occurring radioactive elements, and (b) artificially produced radioisotopes; uses of radioactivity in medicine, (a) clinical diagnostic, (b) therapeutic (c) sterilization of medical equipment and materials; environmental uses as tracers; industrial applications, e.g. tracers and radiography; ensuring safety. (U.K.)

  7. Lessons learned from case studies of inhalation exposures of workers to radioactive aerosols

    Energy Technology Data Exchange (ETDEWEB)

    Hoover, M.D.; Fencl, A.F.; Newton, G.J. [and others

    1995-12-01

    Various Department of Energy requirements, rules, and orders mandate that lessons learned be identified, evaluated, shared, and incorporated into current practices. The recently issued, nonmandatory DOE standard for Development of DOE Lessons Learned Program states that a DOE-wide lessons learned program will {open_quotes}help to prevent recurrences of negative experiences, highlight best practices, and spotlight innovative ways to solve problems or perform work more safely, efficiently, and cost effectively.{close_quotes} Additional information about the lessons learned program is contained in the recently issued DOE handbook on Implementing U.S. Department of Energy Lessons Learned Programs and in October 1995 DOE SAfety Notice on Lessons Learned Programs. This report summarizes work in progress at ITRI to identify lessons learned for worker exposures to radioactive aerosols, and describes how this work will be incorporated into the DOE lessons learned program, including a new technical guide for measuring, modeling, and mitigating airborne radioactive particles. Follow-on work is focusing on preparation of {open_quotes}lessons learned{close_quotes} training materials for facility designers, managers, health protection professionals, line supervisors, and workers.

  8. Lessons learned from case studies of inhalation exposures of workers to radioactive aerosols

    International Nuclear Information System (INIS)

    Hoover, M.D.; Fencl, A.F.; Newton, G.J.

    1995-01-01

    Various Department of Energy requirements, rules, and orders mandate that lessons learned be identified, evaluated, shared, and incorporated into current practices. The recently issued, nonmandatory DOE standard for Development of DOE Lessons Learned Program states that a DOE-wide lessons learned program will open-quotes help to prevent recurrences of negative experiences, highlight best practices, and spotlight innovative ways to solve problems or perform work more safely, efficiently, and cost effectively.close quotes Additional information about the lessons learned program is contained in the recently issued DOE handbook on Implementing U.S. Department of Energy Lessons Learned Programs and in October 1995 DOE SAfety Notice on Lessons Learned Programs. This report summarizes work in progress at ITRI to identify lessons learned for worker exposures to radioactive aerosols, and describes how this work will be incorporated into the DOE lessons learned program, including a new technical guide for measuring, modeling, and mitigating airborne radioactive particles. Follow-on work is focusing on preparation of open-quotes lessons learnedclose quotes training materials for facility designers, managers, health protection professionals, line supervisors, and workers

  9. A reference aerosol for a radon reference chamber

    Science.gov (United States)

    Paul, Annette; Keyser, Uwe

    1996-02-01

    The measurement of radon and radon progenies and the calibration of their detection systems require the production and measurement of aerosols well-defined in size and concentration. In the German radon reference chamber, because of its unique chemical and physical properties, carnauba wax is used to produce standard aerosols. The aerosol size spectra are measured on-line by an aerosol measurement system in the range of 10 nm to 1 μm aerodynamic diameter. The experimental set-ups for the study of adsorption of radioactive ions on aerosols as function of their size and concentration will be described, the results presented and further adaptations for an aerosol jet introduced (for example, for the measurement of short-lived neutron-rich isotopes). Data on the dependence of aerosol radius, ion concentration and element selectivity is collected by using a 252Cf-sf source. The fission products of this source range widely in elements, isotopes and charges. Adsorption and the transport of radioactive ions on aerosols have therefore been studied for various ions for the first time, simultaneously with the aerosol size on-line spectrometry.

  10. A reference aerosol for a radon reference chamber

    Energy Technology Data Exchange (ETDEWEB)

    Paul, A. [Physikalisch-Technische Bundesanstalt, Braunschweig (Germany); Keyser, U. [Physikalisch-Technische Bundesanstalt, Braunschweig (Germany)

    1996-01-11

    The measurement of radon and radon progenies and the calibration of their detection systems require the production and measurement of aerosols well-defined in size and concentration. In the German radon reference chamber, because of its unique chemical and physical properties, carnauba wax is used to produce standard aerosols. The aerosol size spectra are measured on-line by an aerosol measurement system in the range of 10 nm to 1 {mu}m aerodynamic diameter. The experimental set-ups for the study of adsorption of radioactive ions on aerosols as function of their size and concentration are described, the results presented and further adaptations for an aerosol jet introduced (for example, for the measurement of short-lived neutron-rich isotopes). Data on the dependence of aerosol radius, ion concentration and element selectivity is collected by using a {sup 252}Cf-sf source. The fission products of this source range widely in elements, isotopes and charges. Adsorption and the transport of radioactive ions on aerosols have therefore been studied for various ions for the first time, simultaneously with the aerosol size on-line spectrometry. (orig.).

  11. Natural and artificial radioactivity in some protected areas of south east Europe

    Directory of Open Access Journals (Sweden)

    Džoljić Jovana A.

    2017-01-01

    Full Text Available The primary aim of this research is the investigation of natural and artificial radioactivity in protected areas of Kopaonik, Vlasina, and Rila Mountains. Soil samples (including lake sediment, drinkable spring water and conifers at mentioned locations of Southeast Europe, are chosen as study objects due to their importance for people and the environment in global. Specific activities of 226Ra, 232Th, 40K, 238U, 235U, 137Cs, 210Pb, and 7Be are determined using gamma spectrometry and the obtained values compared with literature and mean world values. Risk assessment parameters and the soil-plant transfer factor were determined for 226Ra, 40K, 137Cs, and 210Pb. This is the first radioactivity study of high mountain areas of Vlasina and Kopaonik in Serbia and Rila in Bulgaria and as such a baseline measurement and foundation for future research. [Project of the Serbian Ministry of Education, Science and Technological Development, Grant no. III43009

  12. American Association for Aerosol Research (AAAR) `95

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-12-31

    The Fourteenth annual meeting of the American Association for Aerosol Research was held October 9-13, 1995 at Westin William Penn Hotel in Pittsburgh, PA. This volume contains the abstracts of the papers and poster sessions presented at this meeting, grouped by the session in which they were presented as follows: Radiation Effects; Aerosol Deposition; Collision Simulations and Microphysical Behavior; Filtration Theory and Measurements; Materials Synthesis; Radioactive and Nuclear Aerosols; Aerosol Formation, Thermodynamic Properties, and Behavior; Particle Contamination Issues in the Computer Industry; Pharmaceutical Aerosol Technology; Modeling Global/Regional Aerosols; Visibility; Respiratory Deposition; Biomass and Biogenic Aerosols; Aerosol Dynamics; Atmospheric Aerosols.

  13. Fission-fragment attachment to aerosols and their transport through capillary tubes

    International Nuclear Information System (INIS)

    Novick, V.J.; Alvarez, J.L.; Greenwood, R.C.

    1981-01-01

    The transport of radioactive aerosols was studied using equipment, collectively called the Helium jet, that has been constructed to provide basic nuclear physics data on fission product nuclides. The transport of the fission products in the system depends on their attachment to aerosol particles. The system consists of 1) a tube furnace which generates aerosols by the sublimation or evaporation of source material, 2) a helium stream used to transport the aerosols, 3) a 25 m settling tube to eliminate the larger aerosols and smaller aerosols that would deposit in the capillary, 4) a Californium-252 self-fissioning source of fission product nuclides, and 5) a small capillary to carry the radioactive aerosols from the hot cell to the laboratory. Different source materials were aerosolized but NaCl is generally used because it yielded the highest transport efficiencies through the capillary. Particle size measurments were made with NaCl aerosols by using a cascade impactor, an optical light scattering device, and the capillary itself as a diffusion battery by performing radiation measurements and/or electrical conductivity measurements. Both radioactive and nonradioactive aerosols were measured in order to investigate the possibility of a preferential size range for fission product attachment. The measured size distributions were then used to calculate attachment coefficients and finally an attachment time

  14. Radioactivity Monitoring of the Irish Environment 2007

    International Nuclear Information System (INIS)

    Fegan, M.; Dowdall, A.; Hanley, O.; Hayden, E.; Kelleher, K.; Long, S.; Smith, V.; Somerville, S.; Wong, J.; Pollard, D.

    2008-10-01

    detect the presence of the gas krypton-85. This gas is released into the environment primarity as a result of the reprocessing of nuclear fuel. During 2007, levels of radionuclides in airborne radioactivity were low and consistent with measurements in previous years. External gamma dose rates were monitored continuously at fifteen stations. No abnormal levels were observed. A major upgrade of the aerosol sampling equipment began in 2007 when three on-line low volume systems and seven upgraded off-line low volume systems were installed and commissioned. Two additional on-line sites will be added in 2008. In accordance with the RPII's drinking water monitoring protocol, a number of major water supplies from Cork, Dublin, Galway and Limerick were tested and found to be within the requirements for radioactivity set out in the relevant national standards. In addition, groundwater supplies were tested in nine countries as a pilot for a national survey of ground water scheduled for 2008 to 2010. The RPII sampled and measured levels of radioactivity in mixed diet, milk and various other foodstuffs including milk products, baby foods, beef, lamb and poultry. These measurements show that the levels of artificual radioactivity in the Irish diet continue to be low. One hundred and ninety samples of fish, shellfish, seaweed, seawater and sediment were analysed for a range of radionuclides. Along the Irish coastline the highest activity concentrations observed were in the north-east. The main pathway contributing to the exposure of the Irish public to artificial radioactivity from the marine environment is the consumption of seafood. Caesium-137 continues to be the dominant radionuclide, accounting for approximately 84% of the total dose. The dose to the Irish population from consumption of seafood landed at north-east ports has declined significantly over the last two decades corresponding to the reduction in discharges from Sellafield. The annual doses incurred by the Irish public

  15. Self-charging of 198Au-labeled monodisperse gold aerosols studied with a miniature electrical mobility spectrometer

    International Nuclear Information System (INIS)

    Yeh, H.C.; Newton, G.J.; Raabe, O.G.; Boor, D.R.

    1976-01-01

    Knowledge of the electrostatic character of an aerosol may be essential in assessing its potential inhalation hazard. In inhalation studies with radioactive aerosols, the aerosol charge state may change in the course of transport due to the emission of α, β or γ radiations. This paper describes an experimental study of the self-charging of 198 Au-labeled aerosols of monodisperse gold spheres by β emission. A miniature aerosol electrical mobility spectrometer, suitable for use in inhalation studies with radioactive aerosols, was developed and used in this study. This device is relatively inexpensive, easy to manufacture and its contamination by radioactive material has been minimized. Using polystyrene latex spheres, ranging in diameter from 0.176 to 1.18 μm, the spectrometer was calibrated with flow rates ranging from 400 to 4800 ml/min. Experiments with two sizes of 198 Au-labeled monodisperse gold aerosols were performed. Results indicate that the radioactivity of an aerosol can cause self-charging and affect the charge distribution. (author)

  16. Meteorological support for aerosol radiometers: special aerosol sources

    Energy Technology Data Exchange (ETDEWEB)

    Belkina, S.K.; Zalmanzon, Yu.E.; Kuznetsov, Yu.V.; Fertman, D.E.

    1988-07-01

    A new method is described for transfer of the measure of unit volume activity of radioactive aerosols from the state special standard to the working instruments in the stage of regular operation. The differences from existing methods are examined. The principal distinction of the new method is the possibility of direct (rather than through the conversion factor) determination and subsequent testing of the fundamental meteorological characteristics of the instrument by means of special aerosol sources, which fosters a significant reduction in individual components of the indicated errors.

  17. Code Development on Fission Product Behavior under Severe Accident-Validation of Aerosol Sedimentation

    International Nuclear Information System (INIS)

    Ha, Kwang Soon; Kim, Sung Il; Jang, Jin Sung; Kim, Dong Ha

    2016-01-01

    The gas and aerosol phases of the radioactive materials move through the reactor coolant systems and containments as loaded on the carrier gas or liquid, such as steam or water. Most radioactive materials might escape in the form of aerosols from a nuclear power plant during a severe reactor accident, and it is very important to predict the behavior of these radioactive aerosols in the reactor cooling system and in the containment building under severe accident conditions. Aerosols are designated as very small solid particles or liquid droplets suspended in a gas phase. The suspended solid or liquid particles typically have a range of sizes of 0.01 m to 20 m. Aerosol concentrations in reactor accident analyses are typically less than 100 g/m3 and usually less than 1 g/m3. When there are continuing sources of aerosol to the gas phase or when there are complicated processes involving engineered safety features, much more complicated size distributions develop. It is not uncommon for aerosols in reactor containments to have bimodal size distributions for at least some significant periods of time early during an accident. Salient features of aerosol physics under reactor accident conditions that will affect the nature of the aerosols are (1) the formation of aerosol particles, (2) growth of aerosol particles, (3) shape of aerosol particles. At KAERI, a fission product module has been developed to predict the behaviors of the radioactive materials in the reactor coolant system under severe accident conditions. The fission product module consists of an estimation of the initial inventories, species release from the core, aerosol generation, gas transport, and aerosol transport. The final outcomes of the fission product module designate the radioactive gas and aerosol distribution in the reactor coolant system. The aerosol sedimentation models in the fission product module were validated using ABCOVE and LACE experiments. There were some discrepancies on the predicted

  18. Code Development on Fission Product Behavior under Severe Accident-Validation of Aerosol Sedimentation

    Energy Technology Data Exchange (ETDEWEB)

    Ha, Kwang Soon; Kim, Sung Il; Jang, Jin Sung; Kim, Dong Ha [KAERI, Daejeon (Korea, Republic of)

    2016-05-15

    The gas and aerosol phases of the radioactive materials move through the reactor coolant systems and containments as loaded on the carrier gas or liquid, such as steam or water. Most radioactive materials might escape in the form of aerosols from a nuclear power plant during a severe reactor accident, and it is very important to predict the behavior of these radioactive aerosols in the reactor cooling system and in the containment building under severe accident conditions. Aerosols are designated as very small solid particles or liquid droplets suspended in a gas phase. The suspended solid or liquid particles typically have a range of sizes of 0.01 m to 20 m. Aerosol concentrations in reactor accident analyses are typically less than 100 g/m3 and usually less than 1 g/m3. When there are continuing sources of aerosol to the gas phase or when there are complicated processes involving engineered safety features, much more complicated size distributions develop. It is not uncommon for aerosols in reactor containments to have bimodal size distributions for at least some significant periods of time early during an accident. Salient features of aerosol physics under reactor accident conditions that will affect the nature of the aerosols are (1) the formation of aerosol particles, (2) growth of aerosol particles, (3) shape of aerosol particles. At KAERI, a fission product module has been developed to predict the behaviors of the radioactive materials in the reactor coolant system under severe accident conditions. The fission product module consists of an estimation of the initial inventories, species release from the core, aerosol generation, gas transport, and aerosol transport. The final outcomes of the fission product module designate the radioactive gas and aerosol distribution in the reactor coolant system. The aerosol sedimentation models in the fission product module were validated using ABCOVE and LACE experiments. There were some discrepancies on the predicted

  19. Radioactivity. Centenary of radioactivity discovery

    International Nuclear Information System (INIS)

    Charpak, G.; Tubiana, M.; Bimbot, R.

    1997-01-01

    This small booklet was edited for the occasion of the exhibitions of the celebration of the centenary of radioactivity discovery which took place in various locations in France from 1996 to 1998. It recalls some basic knowledge concerning radioactivity and its applications: history of discovery, atoms and isotopes, radiations, measurement of ionizing radiations, natural and artificial radioactivity, isotope dating and labelling, radiotherapy, nuclear power and reactors, fission and fusion, nuclear wastes, dosimetry, effects and radioprotection. (J.S.)

  20. On-site test of filters in nuclear facilities using radioactive sodium chloride (24Na)-aerosol and methyl iodide (131I)

    International Nuclear Information System (INIS)

    Heidam, N.Z.; Hansen, K.A.; Fenger, J.; Flyger, H.; Hedemann Jensen, P.

    1986-02-01

    The nuclar facilities at Risoe National Laboratory are equipped with high-efficiency filters to protect the environment from routine or accidental releases of radioactive material. The filter efficiency must be tested regularly and a method for on-site control is described. It is based on injection of a radioactive sample in the filter duct, followed by sampling before and after the filter. HEPA-filters are tested with a 24 NaCl-aerosol and charcoal filters with 131 ICH 3 . Normally samples of 1 mCi are used. Penetrations (1 - efficiency) can be determined with a relative uncertainty of 10-15%. (author)

  1. Environmental radioactivity. Measurement and monitoring

    International Nuclear Information System (INIS)

    2009-11-01

    The contribution on environmental radioactivity covers the following issues: natural and artificial radioactivity; continuous monitoring of radioactivity; monitoring authorities and measurement; radioactivity in the living environment; radioactivity in food and feeding stuff; radioactivity of game meat and wild-growing mushrooms; radioactivity in mines; radioactivity in the research center Rossendorf.

  2. Measurement of size distribution for 220Rn progeny attached aerosols

    International Nuclear Information System (INIS)

    Zhang Lei; Guo Qiuju; Zhuo Weihai

    2008-01-01

    The size distribution of radioactive aerosols is a very important factor for evaluating the inner exposure dose contributed by radon and thoron progeny in environments. In order to measure the size distribution of thoron progeny attached radioactive aerosols, a device was developed using wire screens. The count median diameter (CMD) and the geometric standard deviation (GSD) of attached radioactive aerosols were calculated by collecting ThB and using CR-39 as detector. Field measurement results at Yangjiang City in Guangdong Province show that the CMDs distribute between 30 and 130 nm, and the GSDs are between 1.9 and 3.3. It also shows that the more humid country, the smaller CMDs, and the ventilation has great influence on the size distribution of aerosols. The CMDs of adobe house are smaller than that of the concrete houses. (authors)

  3. 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

  4. Natural atmospheric radioactivity

    International Nuclear Information System (INIS)

    Renoux, A.

    1986-01-01

    After having summed up the different old or new units, used in radioactivity and radioprotection, the origins of atmospheric radioactivity are reported. Next the authors deal with the air content in radon, thoron and their radioactive descendants, insisting on the variations of the radon air content and on the radioactive balance between radon and its descendants. Then a few notions concerning the natural radioactive aerosol are developed: electric charge state, granulometric distribution. The possible effects of natural atmospheric radioactivity on man are studied with a distinction between inner irradiation and outer irradiation, an average assessment is shown. Finally the important problem of radon in inhabitations is approached [fr

  5. Analysis of aerosol agglomeration and removal mechanisms relevant to a reactor containment

    International Nuclear Information System (INIS)

    Chiang, H.W.; Mulpuru, S.R.; Lindquist, E.D.

    1995-01-01

    During some Postulated accidents in a nuclear reactor, radioactive aerosols may be formed and could be released from a rupture of the primary heat transport system into the containment. The released aerosols can agglomerate and form larger aerosol particles. The airborne aerosols can be removed from containment atmosphere by deposition onto the walls and other surfaces in contact with the gas-aerosol mixture. The rate of removal of aerosols depends on the aerosol size, which, in turn, is related to the amount of agglomeration of the aerosol particles. The extent of the removal of the aerosol mass from the containment atmosphere is important in determining the potential radioactive releases to the outside atmosphere. In this paper, selected conditions have been assessed to illustrate the significance of agglomeration for situations potentially of interest in containment safety studies

  6. A study of the attachment of thoron decay products to aerosols using an aerosol centrifuge

    International Nuclear Information System (INIS)

    Balakrishnan, V.

    1979-01-01

    The physical attachment of radioactive decay products (particulate, not gas) to polydisperse fluorescein aerosal particles in two size ranges 0.1 μM-0.33 μM radius and 0.25 μM-1.35 μM radius has been studied under dynamic conditions with a view to find the fraction of thoron decay products attached to the aerosals and the particle size distribution of the host aerosols in the atmosphere of uranium mines. The experimental set-up and procedure are described. An aerosol cloud of fluorescein was introduced into a reaction chamber containing a steady source of thoron and decay products were allowed to interact and attach to the aerosols in the chamber. To simulate conditions normally encountered in uranium mining and milling operations, the concentration of aerosol particles was kept high as compared to the number of decay products. The Lovelace Aerosol Particle Separator, which is an advanced, continuous centrifugal aerosol separator, was used to sample and separate the tagged aerosols into various size groups. The radioactivity associated with each group was determined. The results show the same dependence of attachment of decay products on the size of aerosol particles as predicted by the diffusion theory proposed by Lassen and Rau (1960), even though the experimental conditions of the present study do not conform to those required to satisfy the above mentioned diffusion theory. The method employed in this work to study attachment is reproducible and simple and can be adopted in uranium and thorium mines and associated processing industries. (M.G.B.)

  7. Emergency Protection from Aerosols

    Energy Technology Data Exchange (ETDEWEB)

    Cristy, G.A.

    2001-11-13

    Expedient methods were developed that could be used by an average person, using only materials readily available, to protect himself and his family from injury by toxic (e.g., radioactive) aerosols. The most effective means of protection was the use of a household vacuum cleaner to maintain a small positive pressure on a closed house during passage of the aerosol cloud. Protection factors of 800 and above were achieved.

  8. Emergency protection from aerosols

    International Nuclear Information System (INIS)

    Cristy, G.A.; Chester, C.V.

    1981-07-01

    Expedient methods were developed that could be used by an average person, using only materials readily available, to protect himself and his family from injury by toxic (e.g., radioactive) aerosols. The most effective means of protection was the use of a household vacuum cleaner to maintain a small positive pressure on a closed house during passage of the aerosol cloud. Protection factors of 800 and above were achieved

  9. Determination of the concentration of {alpha} emitting radioactive aerosols; Mesure de la concentration des aerosols radioactifs emetteurs {alpha}

    Energy Technology Data Exchange (ETDEWEB)

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

    1953-06-15

    In the first part of this work the techniques used for the quantitative measurement of the concentrations of aerosols carrying short lived (radon or thoron daughters) or long lived (uranium) {alpha} radioactive emitters are described. In the second part the author investigates the problem of the determination of radon concentration in air by means of activity determinations on airborne dusts. Special reference is made to the measurement of the radon active deposit on two types of dusts (iron oxide (yellow) and uranium oxide) in small chambers (6 liters). In the third part are given data resulting from determinations of radon and thoron concentrations in atmospheric air in the south of Paris area using this method. (author) [French] Dans la premiere partie de ce travail on expose les techniques utilisees pour la mesure quantitative des concentrations d'aerosols contenant des emetteurs radioactifs {alpha}, tant pour ceux a vie courte (derives du radon ou du thoron) que pour ceux a vie longue (uranium). Dans la seconde partie on traite le probleme de la determination de la concentration de l'air en radon par la mesure de l'activite des poussieres ayant sejourne dans cet air. En particulier, on indique pour de petits volumes (6 litres) la proportion de depot actif du radon qui est fixee sur deux types de poussieres (limonite et oxyde d'uranium) en fonction de la concentration de celles-ci. Dans la troisieme partie on donne quelques exemples de mesure par cette methode de la concentration en radon et en thoron de l'atmosphere de la region parisienne. (auteur)

  10. Application of artificial neural networks on the characterization of radioactive waste drums

    International Nuclear Information System (INIS)

    Potiens Junior, Ademar Jose; Hiromoto, Goro

    2011-01-01

    The methodology consist of system simulation of drum-detector by Monte Carlo for obtention of counting efficiency. The obtained data were treated and a neural artificial network (RNA) were constructed for evaluation of total activity of drum. For method evaluation measurements were performed in ten position parallel to the drum axis and the results submitted to the RNA. The developed methodology showed to be effective for isotopic characterization of gamma emitter radioactive wastes distributed in a heterogeneous way in a 200 litters drum. The objective of this work as to develop a methodology of analyse for quantification and localization of radionuclides not homogeneous distributed in a 200 liters drum based on the mathematical techniques

  11. Lessons learned from case studies of worker exposures to radioactive aerosols

    International Nuclear Information System (INIS)

    Hoover, M.D.; Guilmette, R.A.; Scott, B.R.

    1995-01-01

    Considerable efforts in the aerosol science and health protection communities are devoted to developing a defensible technical basis for measuring, modeling, and mitigating toxic aerosols. These efforts involve understanding aerosol source terms, projecting potential aerosol releases, describing their behavior in the workplace and environment, developing instruments and techniques to measure the aerosols, designing ways to contain or control the aerosols, modeling and measuring uptake by workers and other people, estimating health effects, and planning appropriate responses. To help in this effort, we have compiled a data base of case studies involving releases of aerosols and worker exposures in a wide range of industries. Sources of information have included personal communications, limited distribution reports, open literature publications, and reports of abnormal occurrences in U.S. Department of Energy facilities and among licensees of the U.S. Nuclear Regulatory Commission. The data base currently includes more than 100 cases. The case studies have been organized according to the radionuclides involved and the circumstances and consequences of the release. This information has been used to address a number of important questions, such as the adequacy of current aerosol sampling and monitoring procedures, areas needing improvement, and strategies for planning for or responding to accidents. One area of particular interest is related to strategies for prospective or retrospective characterization of aerosol source terms. In some cases, worker exposures have involved aerosols that are similar in particle size distribution, composition, and solubility to aerosols routinely produced in the normal process activities. In such cases, prospective characterization of aerosol source terms has provided relevant and useful information

  12. Nuclear aerosol behavior during reactor accidents

    International Nuclear Information System (INIS)

    Williams, M.M.R.

    1990-01-01

    Some early reactor accidents are recalled together with their associated environmental consequences. One such consequence is the generation of radioactive aerosol. We described the various physical processes that such an aerosol cloud undergoes within the secondary containment building. These physical processes are then brought together quantitatively in a balance equation for the aerosol size spectrum as a function of position and time. Methods for solving this equation are discussed and illustrated by the method of moments based upon log-normal and modified gamma distributions. Current problems are outlined and directions for future work into aerosol behavior are suggested. (author)

  13. Ambient radioactivity levels and radiation doses. Annual report 2009

    International Nuclear Information System (INIS)

    Bernhard-Stroel, Claudia; Hachenburger, Claudia; Trugenberger-Schnabel, Angela; Peter, Josef

    2010-12-01

    The annual report on environmental radioactivity and radiation exposure 2009 consists of two parts. Part A: General information: natural environmental radioactivity, artificial radioactivity in the environment, occupational radiation exposure, radiation exposures from medical applications, the handling of radioactive materials and sources of ionizing radiation, non-ionizing radiation. Part B includes current data and their evaluation for natural environmental radioactivity, artificial radioactivity in the environment, occupational radiation exposure, radiation exposures from medical applications, the handling of radioactive materials and sources of ionizing radiation, non-ionizing radiation.

  14. Radioactivity

    International Nuclear Information System (INIS)

    Chelet, Y.

    2006-01-01

    The beginning of this book explains the why and how of the radioactivity, with a presentation of the different modes of disintegration. Are tackled the reports between radioactivity and time before explaining how the mass-energy equivalence appears during disintegrations. Two chapters treat natural radioisotopes and artificial ones. This book makes an important part to the use of radioisotopes in medicine (scintigraphy, radiotherapy), in archaeology and earth sciences (dating) before giving an inventory of radioactive products that form in the nuclear power plants. (N.C.)

  15. Artificial neural networks in the evaluation of the radioactive waste drums activity

    International Nuclear Information System (INIS)

    Potiens, J.R.A.J.; Hiromoto, G.

    2006-01-01

    The mathematical techniques are becoming more important to solve geometry and standard identification problems. The gamma spectrometry of radioactive waste drums would be a complex solution problem. The main difficulty is the detectors calibration for this geometry; the waste is not homogeneously distributed inside the drums, therefore there are many possible combinations between the activity and the position of these radionuclides inside the drums, making the preparation of calibration standards impracticable. This work describes the development of a methodology to estimate the activity of a 200 L radioactive waste drum, as well as a mapping of the waste distribution, using Artificial Neural Network. The neural network data set entry obtaining was based on the possible detection efficiency combination with 10 sources activities varying from 0 to 74 x 10 3 Bq. The set up consists of a 200 L drum divided in 5 layers. Ten detectors were positioned all the way through a parallel line to the drum axis, from 15 cm of its surface. The Cesium -137 radionuclide source was used. The 50 efficiency obtained values (10 detectors and 5 layers), combined with the 10 source intensities resulted in a 100,000 lines for 15 columns matrix, with all the possible combinations of source intensity and the Cs-137 position in the 5 layers of the drum. This archive was divided in 2 parts to compose the set of training: input and target files. The MatLab 7.0 module of neural networks was used for training. The net architecture has 10 neurons in the input layer, 18 in the hidden layer and 5 in the output layer. The training algorithm was the 'traincgb' and after 300 'epoch s' the medium square error was 0.00108172. This methodology allows knowing the detection positions answers in a heterogeneous distribution of radionuclides inside a 200 L waste drum; in consequence it is possible to estimate the total activity of the drum in the training neural network limits. The results accuracy depends

  16. Aerosol in the containment

    International Nuclear Information System (INIS)

    Lanza, S.; Mariotti, P.

    1986-01-01

    The US program LACE (LWR Aerosol Containment Experiments), in which Italy participates together with several European countries, Canada and Japan, aims at evaluating by means of a large scale experimental activity at HEDL the retention in the pipings and primary container of the radioactive aerosol released following severe accidents in light water reactors. At the same time these experiences will make available data through which the codes used to analyse the behaviour of the aerosol in the containment and to verify whether by means of the codes of thermohydraulic computation it is possible to evaluate with sufficient accuracy variable influencing the aerosol behaviour, can be validated. This report shows and compares the results obtained by the participants in the LACE program with the aerosol containment codes NAVA 5 and CONTAIN for the pre-test computations of the test LA 1, in which an accident called containment by pass is simulated

  17. Properties of aerosol floating in the air in a nuclear power plant workplace environment

    International Nuclear Information System (INIS)

    Karasawa, H.; Funabashi, M.; Ito, M.

    1992-01-01

    An investigation was carried out on properties of radioactive aerosol floating in the air at several workplaces in nuclear power plant. The principal results are as follows: the aerosol particle size distributions consisted of two particle groups, whose aerodynamic diameters ranged from 4 to 7 microns and from 0.4 to 0.6 microns; the radioactive aerosol particle size distribution were unimodal. The mean activity median aerodynamic diameter (AMAD) was 6 microns, with geometric standard deviation microns; and, the average density of the aerosol was about 2.2g/cm 3 . (author)

  18. Study of filterable materials and protection instruments by the use of radioactive aerosols; Etude de materiaux filtrants et d'appareils de protection a l'aide des aerosols radioactifs

    Energy Technology Data Exchange (ETDEWEB)

    Billard,; Chevalier,; Pradel, [Commissariat a l' Energie Atomique, Saclay (France).Centre d' Etudes Nucleaires

    1960-07-01

    Many filtration problems can be studied by means of radioactive aerosols. For the investigations described in this paper we have chosen the solid disintegration products of radon, the radioactive gas formed from radium, because of the facilities of generation and measurement it offers. Radon and its daughters are in fact always present in the atmosphere in sufficient concentration for certain tests. In order to improve the sensitivity of the measurements, radon from uranium ore can be used. The technique of measuring by counting {alpha} particles is rapid and easy to employ. We have thus been able to define a test for filterable substances, and to check filtering installation and individual protection instruments. (author) [French] Les aerosols radioactifs permettent d'etudier de nombreux problemes de filtration. Pour les etudes decrites dans ce document, nous avons choisi les produits solides de desintegration du radon, gaz radioactif forme a partir du radium en raison des facilites de generation et de mesure. Le radon et ses descendants sont, en effet, toujours presents dans l'atmosphere en concentration suffisante pour certains essais. Pour ameliorer la sensibilite des mesures, il suffit d'utiliser le radon provenant de minerai d'uranium. La technique de mesure par comptage des particules {alpha} est rapide et facile a mettre en oeuvre. Nous avons pu ainsi definir un test pour les substances filtrantes et controler les installations de filtration et des appareils de protection individuelle. (auteur)

  19. DSMC multicomponent aerosol dynamics: Sampling algorithms and aerosol processes

    Science.gov (United States)

    Palaniswaamy, Geethpriya

    The post-accident nuclear reactor primary and containment environments can be characterized by high temperatures and pressures, and fission products and nuclear aerosols. These aerosols evolve via natural transport processes as well as under the influence of engineered safety features. These aerosols can be hazardous and may pose risk to the public if released into the environment. Computations of their evolution, movement and distribution involve the study of various processes such as coagulation, deposition, condensation, etc., and are influenced by factors such as particle shape, charge, radioactivity and spatial inhomogeneity. These many factors make the numerical study of nuclear aerosol evolution computationally very complicated. The focus of this research is on the use of the Direct Simulation Monte Carlo (DSMC) technique to elucidate the role of various phenomena that influence the nuclear aerosol evolution. In this research, several aerosol processes such as coagulation, deposition, condensation, and source reinforcement are explored for a multi-component, aerosol dynamics problem in a spatially homogeneous medium. Among the various sampling algorithms explored the Metropolis sampling algorithm was found to be effective and fast. Several test problems and test cases are simulated using the DSMC technique. The DSMC results obtained are verified against the analytical and sectional results for appropriate test problems. Results show that the assumption of a single mean density is not appropriate due to the complicated effect of component densities on the aerosol processes. The methods developed and the insights gained will also be helpful in future research on the challenges associated with the description of fission product and aerosol releases.

  20. Papers of the 15. french congress on the aerosols CFA 99; Actes du 15. congres francais sur les aerosols CFA 99

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-07-01

    This french congress on the aerosols took place in Paris the 8 and 9 december 1999. It was presented in four main themes: bio-aerosols and filtering; the aerosols metrology; the aerosols in the environment; aerosols physic and applications. Seven papers have been analyzed in INIS data base for their specific interest in the nuclear industry. They concern the aerosol capture simulation, the aerosols sampling in workplace environment, a ring-effect ion generator development for the charge and the neutralization of an aerosol cloud, the radon 222 characterization in a house, a particle re-entrainment, the electrical charge process of beta emitter radioactive aerosols, the simulation of air flows in many filters. The other ones are analyzed in the ETDE data base. (A.L.B.)

  1. Optimal Performance Simulation of a Metal Fiber Filter for Capturing Radioactive Aerosols

    International Nuclear Information System (INIS)

    Lee, Seung Uk; Lee, Chan Hyun; Park, Min Chan; Lee, Jaek Eun

    2016-01-01

    In this study, the metal fiber filter used for removing radioactive aerosol is systematically dissected and studied in order to figure out the optimal design which can be applied to the actual operation conditions in nuclear heating, ventilation and air conditioning (HVAC) systems for particle collection. In order to derive the optimal design for metal fiber HEPA filter, a numerical model is developed and its results are compared to experimental data to test reliability. Moreover, sensitivity analysis is performed using important parameters to determine which parameters have large influence on the filter performance. Using the model developed in this study, optimal design parameters for pleated metal fiber filters are derived which include fiber diameter less than 4 μm, solidity larger than 0.2, filter thickness larger than 1 mm, and face velocity lower than 5 cm/s. With these conditions, the metal filter qualified for the HEPA filter standard which specified 99.97% efficiency in the 0.3 μm particle size range.

  2. Assessment of need for transport tubes when continuously monitoring for radioactive aerosols

    Energy Technology Data Exchange (ETDEWEB)

    Whicker, J.J.; Rodgers, J.C.; Lopez, R.C.

    1999-09-01

    Aerosol transport tubes are often used to draw aerosol from desirable sampling locations to nearby air sampling equipment that cannot be placed at that location. In many plutonium laboratories at Los Alamos National Laboratory, aerosol transport tubes are used to transport aerosol from the front of room ventilation exhaust registers to continuous air monitors (CAMs) that are mounted on nearby walls. Despite designs to minimize particle loss in tubes, aerosol transport model predictions suggest losses occur lowering the sensitivity of CAMs to accidentally released plutonium aerosol. The goal of this study was to test the hypotheses that the reliability, speed, and sensitivity of aerosol detection would be equal whether the sample was extracted from the front of the exhaust register or from the wall location of CAMs. Polydisperse oil aerosols were released from multiple locations in two plutonium laboratories to simulate plutonium aerosol releases. Networked laser particle counters (LPCs) were positioned to simultaneously measure time-resolved aerosol concentrations at each exhaust register and at each wall-mounted CAM location.

  3. Particle size distribution of radioactive aerosols after the Fukushima and the Chernobyl accidents.

    Science.gov (United States)

    Malá, Helena; Rulík, Petr; Bečková, Vera; Mihalík, Ján; Slezáková, Miriam

    2013-12-01

    Following the Fukushima accident, a series of aerosol samples were taken between 24th March and 13th April 2011 by cascade impactors in the Czech Republic to obtain the size distribution of (131)I, (134)Cs, (137)Cs, and (7)Be aerosols. All distributions could be considered monomodal. The arithmetic means of the activity median aerodynamic diameters (AMADs) for artificial radionuclides and for (7)Be were 0.43 and 0.41 μm with GDSs 3.6 and 3.0, respectively. The time course of the AMADs of (134)Cs, (137)Cs and (7)Be in the sampled period showed a slight decrease at a significance level of 0.05, whereas the AMAD pertaining to (131)I increased at a significance level of 0.1. Results obtained after the Fukushima accident were compared with results obtained after the Chernobyl accident. The radionuclides released during the Chernobyl accident for which we determined the AMAD fell into two categories: refractory radionuclides ((140)Ba, (140)La (141)Ce, (144)Ce, (95)Zr and (95)Nb) and volatile radionuclides ((134)Cs, (137)Cs, (103)Ru, (106)Ru, (131)I, and (132)Te). The AMAD of the refractory radionuclides was approximately 3 times higher than the AMAD of the volatile radionuclides; nevertheless, the size distributions for volatile radionuclides having a mean AMAD value of 0.51 μm were very close to the distributions after the Fukushima accident. Copyright © 2013 Elsevier Ltd. All rights reserved.

  4. The radioactive component of air pollution in uranium mines. Present data

    International Nuclear Information System (INIS)

    Renoux, A.; Madelaine, G.; Zettwoog, P.

    1982-01-01

    An efficient radiation protection of uranium mine workers requires that the radioactive component of the mine aerosol be well known. Investigations were developed to that purpose in the Fanay mine, La Crouzille near Limoges. Carried out mainly on radon 222 daughters, whose potential hazard is demonstrated to be the main one, they considered the radioactive desequilibrium between radon and its daughter-products, the free fraction, the particle size distribution and the electric charge of the mine radioactive aerosol [fr

  5. Environmental radioactivity monitoring in Republic of Serbia

    International Nuclear Information System (INIS)

    Joksic, J.; Radenkovic, M.; Tanaskovic, I.; Vujovic, M.; Vuletic

    2011-01-01

    According to environmental radioactivity monitoring programme continuous measurements of radioactivity in different samples are performed. Measurements are performed in aerosol samples, fallout, soil, surface waters, drinking water, food of animal and plant origin, milk and feeding stuffs. [sr

  6. Airborne radioactive contamination following aerosol ventilation studies

    International Nuclear Information System (INIS)

    Mackie, A.; Hart, G.C.; Ibbett, D.A.; Whitehead, R.J.S.

    1994-01-01

    Lung aerosol ventilation studies may be accompanied by airborne contamination, with subsequent surface contamination. Airborne contamination has been measured prior to, during and following 59 consecutive 99 Tc m -diethylenetriamine pentaacetate (DTPA) aerosol studies using a personal air sampler. Airborne contamination ranging between 0 and 20 330 kBq m -3 has been measured. Airborne contamination increases with degree of patient breathing difficulty. The effective dose equivalent (EDE) to staff from ingested activity has been calculated to be 0.3 μSv per study. This figure is supported by data from gamma camera images of a contaminated staff member. However, surface contamination measurements reveal that 60% of studies exceed maximum permissible contamination limits for the hands; 16% of studies exceed limits for controlled area surfaces. (author)

  7. The control of water radioactivity

    International Nuclear Information System (INIS)

    Bovard, P.; Graubey, A.

    1962-01-01

    This report presents the different apparatuses and devices used to control and adjust routine releases, to detect accidental pollutions, and to identify the origins of an increased radioactivity. The objective is to perform permanent and continuous sampling and measurement. Samplers and measurement devices (Geiger probes, resin-based integrators, dry aerosol radioactivity recorders and dry sample radioactivity recorders) are presented. Water control stations are presented: these stations are either fixed, or mobile or floating

  8. Assessment of need for transport tubes when continuously monitoring for radioactive aerosols.

    Science.gov (United States)

    Whicker, J J; Rodgers, J C; Lopez, R C

    1999-09-01

    Aerosol transport tubes are often used to draw aerosol from desirable sampling locations to nearby air sampling equipment that cannot be placed at that location. In many plutonium laboratories at Los Alamos National Laboratory, aerosol transport tubes are used to transport aerosol from the front of room ventilation exhaust registers to continuous air monitors (CAMs) that are mounted on nearby walls. Transport tubes are used because past guidance suggests that extraction of aerosol samples from exhaust locations provides the most sensitive and reliable detection under conditions where the rooms have unpredictable release locations and significant spatial variability in aerosol concentrations after releases, and where CAMs cannot be located in front of exhaust registers without blocking worker walkways. Despite designs to minimize particle loss in tubes, aerosol transport model predictions suggest losses occur lowering the sensitivity of CAMs to accidentally released plutonium aerosol. The goal of this study was to test the hypotheses that the reliability, speed, and sensitivity of aerosol detection would be equal whether the sample was extracted from the front of the exhaust register or from the wall location of CAMs. Polydisperse oil aerosols were released from multiple locations in two plutonium laboratories to simulate plutonium aerosol releases. Networked laser particle counters (LPCs) were positioned to simultaneously measure time-resolved aerosol concentrations at each exhaust register (representative of sampling with transport tubes) and at each wall-mounted CAM location (representative of sampling without transport tubes). Results showed no significant differences in detection reliability, speed, or sensitivity for LPCs positioned at exhaust locations when compared to LPCs positioned at the CAM wall location. Therefore, elimination of transport tubes would likely improve CAM performance.

  9. Monitoring artificial radioactivity in the Nordic countries. BER-2 final report

    International Nuclear Information System (INIS)

    Bennerstedt, T.; Rantanen, H.; Mortensen, B.N.

    1994-05-01

    This final report of the Nordic Nuclear Safety Research Project BER-2 gives detailed information on the monitoring of artificial radioactivity in the Nordic countries (Denmark, Finland, Iceland, Norway and Sweden). A comparison shows that for early warning the Nordic countries use a mix of stations measuring external gamma radiation and stations measuring airborne radioactivity. There is a trade-off between fast alarms and the sensitivity threshold. Total gamma measuring stations cannot detect increases smaller than the variations of normal background. Some stations, notably all Danish stations, are equipped with sodium iodide (NaI) type detectors, and operated in such a way that stray peaks due to an increase in the natural radon background can be subtracted. A Nordic Radiation Data Exchange System has been set up and tested on a trial basis. This system focuses on dose rate data from the automatic gamma monitoring stations. An important goal achieved in the project was to determine which data is essential, and to specify a common format for the data exchange. Various telecommunication methods have been tested, and the actual transfer of monitoring results between the Nordic countries was started. It is recommended as a future approach that every country appoint one organization with the responsibility of operating a national information data base, which can be commonly accessed from all the Nordic countries. A procedure for establishing a system of this type has been outlined

  10. A Novel Fireball Analysis for an Explosive Aerosolization Study

    International Nuclear Information System (INIS)

    Sharon, A.; Halevy, I.; Sattinger, D.; Banaim, P.; Yaar, I.; Krantz, L.; Pinhas, M.

    2014-01-01

    The final consequent risk following an explosion of radiological dispersal device (RDD) is highly depends on final radioactive particles’ size distribution creates by detonation shock wave. Respirable, aerosols contribute to risk in a different way when compare it to non respirable aerosols or to ballistic, inertial, particles or even larger fragments. While aerosols (both, respirable and non respirable) are moving downwind with the cloud, heavier, inertial particles escape the initial fireball and deposited on the ground at a short distances from the ground zero (GZ) point. Respirable aerosols are risky when inhaled into the body (internal radiation) while non respirable have risk as an external exposure on the skin and from a distance. Hence, knowing the size distribution of the radioactive particles will, thus, enable more realistic risk assessment predictions. We show here that detonation fireball fast multispectral radiometrycan be a novel tool that can be indicative to the final particles size distribution

  11. The variation of organ doses with the particle size and chemical form of an inhaled radioactive aerosol

    International Nuclear Information System (INIS)

    Hunt, B.W.; Adams, N.; Reissland, J.A.

    1979-04-01

    In this report, radiation doses to organs are calculated as a function of the particle size of the inhaled radioactive material. Aerosols with an Activity Median Aerodynamic Diameter (AMAD) from 0.1 μm to 20 μm are considered and doses accumulated by various organs in periods ranging from 1 day to 70 years are given for 65 radionuclides. A computer program is used which calculates the transformations taking place in each organ per curie of inhaled nuclide from the basic radioactivity and metabolic data. The program also calculates the resulting doses both for the organ in which the transformations occur and from penetrating radiation emitted as a result of transformations in other organs. The effects of particle size and chemical form of the nuclides on the doses received by organs are discussed. Tables of doses accumulated by 10 specific organs and other organs together with effective whole body doses are given for particle sizes 0.1 μm, 1 μm and 10 μm (AMAD). (author)

  12. Environmental radioactivity. Measurement and monitoring; Umweltradioaktivitaet. Messung und Ueberwachung

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2009-11-15

    The contribution on environmental radioactivity covers the following issues: natural and artificial radioactivity; continuous monitoring of radioactivity; monitoring authorities and measurement; radioactivity in the living environment; radioactivity in food and feeding stuff; radioactivity of game meat and wild-growing mushrooms; radioactivity in mines; radioactivity in the research center Rossendorf.

  13. Evaluation of a radioactive aerosol surveillance system

    International Nuclear Information System (INIS)

    Scripsick, R.C.; Stafford, R.G.; Beckman, R.J.; Tillery, M.I.; Romero, P.O.

    Measurements of the dilution of air contaminants between worker breathing zone and area air samplers were made by releasing a test aerosol in a workroom equipped with an aerosol surveillance system. The data were used to evaluate performance, and suggest improvements in design of the workroom's alarming air monitor system. It was found that a breathing zone concentration of 960 times the maximum permissible concentration in air (MPC/sub a/) for a half-hour was required to trigger alarms of the existing monitoring system under some release conditions. Alternative air monitor placement, suggested from dilution measurements, would reduce this average triggering concentration to 354 MPC/sub a/. Deployment of additional air monitors could further reduce the average triggering concentration to 241 MPC/sub a/. The relation between number of monitors and triggering concentration was studied. No significant decrease in average triggering concentration was noted for arrays containing greater than five monitors

  14. Radioactivity: A Natural Phenomenon.

    Science.gov (United States)

    Ronneau, C.

    1990-01-01

    Discussed is misinformation people have on the subject of radiation. The importance of comparing artificial source levels of radiation to natural levels is emphasized. Measurements of radioactivity, its consequences, and comparisons between the risks induced by radiation in the environment and from artificial sources are included. (KR)

  15. Realization of radioactive equilibrium in the KRISS radon chamber

    International Nuclear Information System (INIS)

    Lee, Mo Sung; Park, Tae Soon; Lee, Jong Man

    2013-01-01

    The maintenance of radioactive equilibrium between radon and its decay products in a radon chamber is necessary to calibrate radon decay product monitors. In this study, the activity concentrations of radon decay products have been measured, and mosquito-repellent incense has been used to produce aerosol particles in the chamber. Filter papers with 8 μm pore size were used to collect aerosol in the chamber. The activity concentrations of radon decay products have been evaluated by the Modified Tsivoglou Method. The correction factors due to the differences in counting time requirements of the Modified Tsivoglou Method and the time delay between consecutive measurements have been determined. Finally, the radioactive equilibrium has been confirmed by applying the Bateman equation. - Highlights: • The activity concentrations of radon decay products are evaluated by the Modified Tsivoglou Method. • Mosquito-repellent incense is used to produce aerosol particles in the radon chamber. • The radioactive equilibrium in the chamber was achieved within 2 days and confirmed by the Bateman equation

  16. Ventilation conditions and atmospheric characteristics of a laboratory uranium mine. Application to the distribution of radioactive particles in the respiratory tract

    International Nuclear Information System (INIS)

    Duport, Philippe.

    1978-09-01

    The CEA laboratory uranium mine and the characteristics of its ventilation are described. A method of measuring air flows based on the determination of a tracer gas was developed. Variations of radon concentrations and of its daughter products concentrations and radioactive equilibrium were observed as a function of the various ventilation rates. Particle size distribution of radioactive aerosols was studied in the laboratory mine when unoperated. Several methods of evaluation of the free fraction were compared, and the application of the laws of aerosol physics to the production of radioactive aerosols in a mine was investigated. A study of radioactive ions showed that the usual equations of atmospheric electricity could be applied to charged radioactive aerosols in a mine. Finally an experimental method was developed in order to directly examine the deposit of an aerosol labelled by radon daughter products in the respiratory tract of animals. The experimental results obtained with aerosols in the particle size range 5.10 -8 - 5.10 -6 were compared to the theoretical data derived from models published in the literature [fr

  17. Radioactive airborne species formed in the air in high energy accelerator tunnels

    International Nuclear Information System (INIS)

    Kondo, K.

    2005-01-01

    Many radioactive airborne species have been observed in the air of high energy accelerator tunnels during machine operation. Radiation protection against these induced airborne radioactivities is one of the key issues for radiation safety, especially at high-energy and high-intense proton accelerators such as the J-PARC (Japan Proton Accelerator Research Complex, Joint project of KEK and JAERI), which is now under construction at the TOKAI site of JAERI. Information on the chemical forms and particle sizes of airborne radioactivities is essential for the estimation of internal doses. For that purpose, the study on radioactive airborne species formed in the air of beam-line tunnels at high-energy accelerators have been extensively conducted by our group. For Be-7, Na-24, S-38, Cl-38,-39, C-11, and N-13, formed by various types of nuclear reactions including nuclear spallation reactions, their aerosol and gaseous fractions are determined by a filter technique. A parallel plate diffusion battery is used for the measurement of aerosol size distributions, and the formation of radioactive aerosols is explained by the attachment of radionuclides to ambient non-radioactive aerosols which are formed through radiation induced reactions. The chemical forms of gaseous species are also determined by using a selective collection method based on a filter technique. A review is given of the physico-chemical properties of these airborne radionuclides produced in the air of accelerator beam-line tunnels.

  18. Analysis of internal radiation and radiotoxicity source base on aerosol distribution in RMI

    International Nuclear Information System (INIS)

    Yuwono, I.

    2000-01-01

    Destructive testing of nuclear fuel element during post irradiation examination in radio metallurgy installation may cause air contamination in the working area in the form of radioactive aerosol. Inhalation of the radioactive aerosol by worker will to become internal radiation source. Potential hazard of radioactive particle in the body also depends on the particle size. Analysis of internal radiation source and radiotoxicity showed that in the normal operation only natural radioactive materials are found with high radiotoxicity, i.e. Pb-212 and Ac-228. High deposit in the alveolar instersial (Ai) is 95 % and lower in the bronchial area (BB) is 1 % for particle size 11.7 nm and 350 nm respectively. (author)

  19. Fast Multispectral Fireball Analyses and the Relation to Particles’ Aerosolization

    International Nuclear Information System (INIS)

    Sharon, A.; Halevy, I.; Sattinger, D.; Berenstein, Z.; Neuman, R.; Banaim, P.; Pinhas, M.; Yaar, I.

    2014-01-01

    One of the key questions in analyzing the consequent risk following an explosion of radiological dispersal device (RDD) is the final radioactive particles’ size distribution caused by the detonation. Fine, respirable, aerosols behave different when compare it to large, non respirable, aerosols or to inertial particles. While aerosols (both, respirable and non respirable) are trapped inside the detonation cloud moving downwind with the cloud, heavier, inertial particles escape the initial fireball and settled on the ground at a short distances due to hydrodynamic drug. Respirable aerosols are mostly risky when inhaled into the body (internal radiation) while non respirable are risky as an external exposure agents (both on the skin and from a distance). Knowing the size distribution of the radioactive particles will, thus, enable more realistic risk assessment predictions of such events. Fast multispectral radiometry of detonation fireballs can be used as novel tool for the estimation of the RA material final size distribution

  20. Results and code prediction comparisons of lithium-air reaction and aerosol behavior tests

    International Nuclear Information System (INIS)

    Jeppson, D.W.

    1986-03-01

    The Hanford Engineering Development Laboratory (HEDL) Fusion Safety Support Studies include evaluation of potential safety and environmental concerns associated with the use of liquid lithium as a breeder and coolant for fusion reactors. Potential mechanisms for volatilization and transport of radioactive metallic species associated with breeder materials are of particular interest. Liquid lithium pool-air reaction and aerosol behavior tests were conducted with lithium masses up to 100 kg within the 850-m 3 containment vessel in the Containment Systems Test Facility. Lithium-air reaction rates, aerosol generation rates, aerosol behavior and characterization, as well as containment atmosphere temperature and pressure responses were determined. Pool-air reaction and aerosol behavior test results were compared with computer code calculations for reaction rates, containment atmosphere response, and aerosol behavior. The volatility of potentially radioactive metallic species from a lithium pool-air reaction was measured. The response of various aerosol detectors to the aerosol generated was determined. Liquid lithium spray tests in air and in nitrogen atmospheres were conducted with lithium temperatures of about 427 0 and 650 0 C. Lithium reaction rates, containment atmosphere response, and aerosol generation and characterization were determined for these spray tests

  1. Disposal of radioactive wastes from Czechoslovak nuclear power plants

    International Nuclear Information System (INIS)

    Neumann, L.

    In gaseous radioactive waste disposal, aerosol particles are filtered and gaseous wastes are discharged in the environment. The filters and filter materials used are stored on solid radioactive waste storage sites in the individual power plants. Liquid radioactive wastes are concentrated and the concentrates are stored. Distillates and low-level radioactive waste water are discharged into the hydrosphere. Solid radioactive wastes are stored without treatment in power plant bunkers. Bituminization and cementation of liquid radioactive wastes are discussed. (H.S.)

  2. Papers of the 15. french congress on the aerosols CFA 99

    International Nuclear Information System (INIS)

    2000-01-01

    This french congress on the aerosols took place in Paris the 8 and 9 december 1999. It was presented in four main themes: bio-aerosols and filtering; the aerosols metrology; the aerosols in the environment; aerosols physic and applications. Seven papers have been analyzed in INIS data base for their specific interest in the nuclear industry. They concern the aerosol capture simulation, the aerosols sampling in workplace environment, a ring-effect ion generator development for the charge and the neutralization of an aerosol cloud, the radon 222 characterization in a house, a particle re-entrainment, the electrical charge process of beta emitter radioactive aerosols, the simulation of air flows in many filters. The other ones are analyzed in the ETDE data base. (A.L.B.)

  3. Artificial radioactivity in tide washed pastures in south west Scotland

    International Nuclear Information System (INIS)

    McKay, W.A.; Bonnett, P.J.P.; Barr, H.M.; Howorth, J.M.

    1991-01-01

    A study has been carried out to determine the impact of Sellafield discharges on the levels of radioactivity in tide washed pastures in south west Scotland. The likely areas of tidal inundations along the Nith, Urr, Dee, Fleet and Cree (including nearby Bladnoch) rivers were assessed using maps and aerials photographs. These were then visited and gamma radiation measurements taken at regular intervals to enable the external dose from anthropogenic nuclides to be estimated. A further survey followed where soil cores were taken from the areas on each river where the external dose appeared highest and analysed for a range of artificial radionuclides. The levels of 137 Cs, 134 Cs, 238 Pu, 239+240 Pu and 241 Am found, although small, were clearly in excess of the background from other sources. A habit survey was carried out to provide site specific information of tide washed pasture usage, which, with the spatial radionuclide data was used to estimate doses to appropriate critical groups. The maximum annual dose calculated to arise was 60 μSv which is less than 6% of the ICRP principal dose limit of 1 mSv. (author)

  4. Study on the Metal Fiber Filter Modeling for Capturing Radioactive Aerosol

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Seunguk; Lee, Chanhyun; Park, Minchan; Lee, Jaekeun [EcoEnergy Research Institute, Busan (Korea, Republic of)

    2015-05-15

    The components of air cleaning system are demisters to remove entrained moisture, pre-filters to remove the bulk of the particulate matter, high efficiency particulate air (HEPA) filters, iodine absorbers(generally, activated carbon) and HEPA filters after the absorbers for redundancy and collection of carbon fines. The HEPA filters are most important components to prevent radioactive aerosols from being released to control room and adjacent environment. The Conventional HEPA filter has pleated media for low pressure drop. Consequently, the filters must provide high collection efficiency as well as low pressure drop. Unfortunately, conventional HEPA filters are made of glass fiber and polyester, and pose disposal issues since they cannot be recycled. In fact, 31,055 HEPA filters used in nuclear facilities in the U.S are annually disposed. The Analyses at face velocities 1cm/s and 10cm/s are also carried out, and they also show R2 value of 0.995. However, since official HEPA filter standards are established at face velocity of 5cm/s, this value will be used in further analysis. From the comparative studies carried out at different filter thickness and face velocities, a good correlation is found between the model and the experiment.

  5. Ambient radioactivity levels and radiation doses. Annual report 2011

    International Nuclear Information System (INIS)

    Bernhard-Stroel, Claudia; Hachenburger, Claudia; Trugenberger-Schnabel, Angela; Peter, Josef

    2013-07-01

    The annual report 2011 on ambient radioactivity levels and radiation doses covers the following issues: Part A: Natural environmental radioactivity, artificial radioactivity in the environment, occupational radiation exposure, radiation exposure from medical applications, the handling of radioactive materials and sources of ionizing radiation, non-ionizing radiation. Part B; Current data and their evaluation: Natural environmental radioactivity, artificial radioactivity in the environment, occupational radiation exposure, radiation exposure from medical applications, the handling of radioactive materials and sources of ionizing radiation, non-ionizing radiation. The Appendix includes Explanations of terms, radiation doses and related units, external and internal radiation exposure, stochastic and deterministic radiation effects, genetic radiation effects, induction of malignant neoplasm, risk assessment, physical units and glossary, laws, ordinances, guidelines, recommendations and other regulations concerning radiation protection, list of selected radionuclides.

  6. Forest decline, natural and technically generated radioactivity

    International Nuclear Information System (INIS)

    Teufel, D.

    1983-06-01

    The question investigated is whether the radioactive rare gases emanating from nuclear plants are causative or participate in the triggering of forest disease. For one thing, a chemical reaction could be responsible for such an effect exerted by these artificial radioactive effluents. However, a calculation shows the concentration of radionuclides, respectively, in this case, their decomposition products, to be by many orders of magnitude smaller than other constituents in air; so a chemical reaction of this kind may be excluded. For the other part, rare gases might contribute to forest damage by their radioactive decomposition and late physical, chemical, and biological effects. In this connection, a detailed analysis is made of the comparability of natural radioactivity with radioactivity generated by nuclear plants. A possible contribution towards the total stress situation of forests (chemical air pollution, natural radioactivity, artificially produced radioactive rare gases, weather conditions and conditions arising from forest management and the like) would amount to a proportion smaller than 1/1000 considering natural radioactivity as a possible stress factor only. (orig.) [de

  7. Difference in inhaled aerosol deposition patterns in the lungs due to three different sized aerosols

    International Nuclear Information System (INIS)

    Miki, M.; Isawa, T.; Teshima, T.; Anazawa, Y.; Motomiya, M.

    1992-01-01

    Deposition patterns of inhaled aerosol in the lungs were studied in five normal subjects and 20 patients with lung disease by inhaling radioaerosols with three different particle size distributions. Particle size distributions were 0.84, 1.04 and 1.93 μm in activity median aerodynamic diameter (AMAD) with its geometric standard deviation (σg) of 1.73, 1.71 and 1.52, respectively. Deposition patterns of inhaled aerosols were compared qualitatively and quantitatively by studying six different parameters: alveolar deposition ratio (ALDR), X max , X mean , standard deviation (S.D.), skewness and kurtosis of the radioactive distribution in the lungs following inhalation. It has been found that aerosol deposition patterns varied with particle size. The unevenness of aerosol deposition, X max , X mean and the number of 'hot spots' became more prominent with increase in particle size, whereas values of ALDR and S.D. decreased as particle size increased. (author)

  8. Unveiling aerosol-cloud interactions - Part 1: Cloud contamination in satellite products enhances the aerosol indirect forcing estimate

    Science.gov (United States)

    Christensen, Matthew W.; Neubauer, David; Poulsen, Caroline A.; Thomas, Gareth E.; McGarragh, Gregory R.; Povey, Adam C.; Proud, Simon R.; Grainger, Roy G.

    2017-11-01

    Increased concentrations of aerosol can enhance the albedo of warm low-level cloud. Accurately quantifying this relationship from space is challenging due in part to contamination of aerosol statistics near clouds. Aerosol retrievals near clouds can be influenced by stray cloud particles in areas assumed to be cloud-free, particle swelling by humidification, shadows and enhanced scattering into the aerosol field from (3-D radiative transfer) clouds. To screen for this contamination we have developed a new cloud-aerosol pairing algorithm (CAPA) to link cloud observations to the nearest aerosol retrieval within the satellite image. The distance between each aerosol retrieval and nearest cloud is also computed in CAPA. Results from two independent satellite imagers, the Advanced Along-Track Scanning Radiometer (AATSR) and Moderate Resolution Imaging Spectroradiometer (MODIS), show a marked reduction in the strength of the intrinsic aerosol indirect radiative forcing when selecting aerosol pairs that are located farther away from the clouds (-0.28±0.26 W m-2) compared to those including pairs that are within 15 km of the nearest cloud (-0.49±0.18 W m-2). The larger aerosol optical depths in closer proximity to cloud artificially enhance the relationship between aerosol-loading, cloud albedo, and cloud fraction. These results suggest that previous satellite-based radiative forcing estimates represented in key climate reports may be exaggerated due to the inclusion of retrieval artefacts in the aerosol located near clouds.

  9. Determination of natural and artificial radioactivity in soil at North Lebanon province.

    Science.gov (United States)

    El Samad, O; Baydoun, R; Nsouli, B; Darwish, T

    2013-11-01

    The concentrations of natural and artificial radionuclides at 57 sampling locations along the North Province of Lebanon are reported. The samples were collected from uncultivated areas in a region not previously reported. The samples were analyzed by gamma spectrometers with High Purity Germanium detectors of 30% and 40% relative efficiency. The activity concentrations of primordial naturally occurring radionuclides of (238)U, (232)Th, and (40)K varied between 4-73 Bq kg(-1), 5-50 Bq kg(-1), and 57-554 Bq kg(-1) respectively. The surface activity concentrations due to the presence of these radionuclides were calculated and Kriging-geostatistical method was used to plot the obtained data on the Lebanese radioactive map. The results for (238)U, (232)Th, and (40)K ranged from 0.2 kBq m(-2) to 9 kBq m(-2), from 0.2 kBq m(-2) to 3 kBq m(-2), and from 3 kBq m(-2) to 29 kBq m(-2) respectively. For the anthropogenic radionuclides, the activity concentrations of (137)Cs founded in soil ranged from 2 Bq kg(-1) to 113 Bq kg(-1), and the surface activity concentration from 0.1 kBq m(-2) to 5 kBq m(-2). The total absorbed gamma dose rates in air from natural and artificial radionuclides in these locations were calculated. The minimum value was 6 nGy h(-1) and the highest one was 135 nGy h(-1) with an average of 55 nGy h(-1) in which the natural terrestrial radiation contributes in 99% and the artificial radionuclides mainly (137)Cs contributes only in 1%. The total effective dose calculated varied in the range of 7 μSv y(-1) and 166 μSv y(-1) while the average value was 69 μSv y(-1) which is below the permissible limit 1000 μSv y(-1). Copyright © 2013 Elsevier Ltd. All rights reserved.

  10. Released radioactivity reducing device

    International Nuclear Information System (INIS)

    Miyamoto, Yumi.

    1995-01-01

    A water scrubber is disposed in a scrubber tank and a stainless steel fiber filter is disposed above the water scrubber. The upper end of the scrubber tank is connected by way of a second bent tube to a capturing vessel incorporating a moisture removing layer and an activated carbon filter. The exit of the capturing vessel is connected to a stack. Upon occurrence of an accident of a BWR-type power plant, gases containing radioactive materials released from a reactor container are discharged into the water scrubber from a first bent tube through a venturi tube nozzle, and water soluble and aerosol-like radioactive materials are captured in the water. Aerosol and splashes of water droplets which can not be captured thoroughly by the water scrubber are captured by the stainless steel fiber filter. Gases passing through the scrubber tank are introduced to a capturing vessel through a second bent tube, and organic iodine is captured by the activated carbon filter. (I.N.)

  11. Sodium oxide aerosol behavior in a closed vessel. Comparison of computer modeling with aerosol experiments

    International Nuclear Information System (INIS)

    Fermandjian, Jean.

    1979-08-01

    Fast breeder reactor safety needs models validated to predict the behavior of sodium aerosols in the different reactor compartments during hypothetical sodium accident. Besides their chemical toxicity, the sodium aerosols are a transfer vector of radioactivity during a contaminated sodium fire. The purpose of this work is to validate models (HAARM 2 and PARDISEKO 3) with tests of sodium pool fires in a 400 m 3 concrete vessel in a confined atmosphere (CASSANDRE tests). The comparison between calculations and experimental results reveals that difficulties still exist, especially as to the selection of the values to be given to some input parameters (physical data of experimental origin, in particular the aerosols source function, the characteristics of the distribution of the emitted particles and the form factor of the agglomerated particles) [fr

  12. Medical imaging was boosted by the discovery of artificial radioactivity; L'imagerie medicale revelee par la radioactivite

    Energy Technology Data Exchange (ETDEWEB)

    Demarthon, F; Dupuy-Maury, F; Donnars, O

    2002-08-01

    This article draws the history of medical imaging since the discovery of artificial radioactivity in 1934. The author reviews the PET (positron emission tomography) and MRI (magnetic resonance imaging) technologies and presents the recent progress in neuro-sciences that have been made possible by using these 2 technologies. Brain imaging has allowed to show: - the impact of emotions on logical mental processes and on mental performances, - the management of memory in the brain of talented quick reckoners, - the degeneration of neurons, and - the link between autism and the presence of structural and functional anomalies in the brain. (A.C.)

  13. Study of the artificial radioactivity of the marine medium using gamma spectrometry (1962-1966)

    International Nuclear Information System (INIS)

    Chesselet, R.

    1969-01-01

    The results described in this study are relative to the artificial radioactivity of such elements as zirconium-95, niobium-95, ruthenium-103, ruthenium-106, cerium-141, cerium-144 and praseodymium-144 which were present in the atmospheric fallout between 1962 and 1964, and their incidence in superficial marine waters. Various physical, chemical or biological processes are studied by a high sensitivity gamma ray spectrometry technic, using those radioelements as 'tracers'. The change of state in sea water of an important fraction (about 50 per cent) of the radioactive particles going into the soluble phase - this phenomenon was not expected for those radioelements - controls the processes of accumulation in the planktonic biomass and the diffusion towards deeper waters. On the other hand, an 'in situ' spectrometry method is described. It enables the direct measurement in the sea of very low concentrations of some gamma ray emitters. The application of this method has made possible to carry out numerous observations in the surface waters of the Western Mediterranean sea and in the Bay of Biscay. It is shown that the mixing depth is closely connected to the depth of the thermocline. An accumulation process at this level is observed. The diffusion coefficients are similar to the thermal turbulent coefficient. The existence during several months of 'compartments' is established for the surface waters of the Bay of Biscay. From the establishment of the budget of fall-out, a comparative study shows that the rate of radioactive fallout on the maritime zone considered is always two to three times higher than on the neighbouring continental regions. Several explanations of this phenomenon are discussed. (author) [fr

  14. 3 Artificial and Natural Radioactivity.cdr

    African Journals Online (AJOL)

    Administrator

    The environment is defined within the ... Radiation Dose Assessment in the Vicinity of Ghana ... Radioactivity concentrations of Ra, Th, K and Cs in soil samples and water sources around the .... predominant rock type of the GAEC and its.

  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. Development and evaluation of an impactor sampler for radioactive aerosol particles

    International Nuclear Information System (INIS)

    Sorimachi, Atsuyuki; Kranrod, Chutima; Chantrarayotha, Supitcha; Tokonami, Shinji

    2008-01-01

    This sampler consists of one impaction stage, which allows separation of airborne particles by 1 μm particle size cut-off point with a 50% probability of impaction, followed by a back-up filter at a flow rate of 1 L min -1 . The particles size more than and less than 1 μm-diameter are collected on the impactor plate at the nozzle side and on the filter, respectively. A Cr-39 detector is mounted on the filter sides of the impaction plate; α particles emitted from the particles less than 1 μm-diameter are counted with the Cr-39 detectors. In order to separate α particles emitted from radon, thoron and their progeny, the Cr-39 detectors are covered with aluminum-vaporized Mylar films. The total thickness of films is adjusted to let their α particles impinge on the Cr-39 detectors. Laboratory tests are going on in terms of the spectral characteristics of α particles before and after passing through the films, the count rate performance of Cr-39 detectors by α particles, the actual collection efficiency of aerosol particles on the impaction plate, and so on. This sampler may be able to supply us with an interesting technique for measuring radon and thoron progeny come from the sources of natural radiation such as the naturally occurred radioactive materials. (author)

  17. Natural and artificial radioactivity in commercial food for domestic animals

    International Nuclear Information System (INIS)

    Cavalcante, Fernanda

    2017-01-01

    The levels of natural radioactivity throughout the planet and their eventual consequences are studied by Environmental Radioprotection. Over the past years, the international agencies concerned with radiation protection have debated over the practices conducted so far, regarding the protection of the fauna and ora, which believed that the recommendations implemented for human beings assured that other species were also protected. Thus, assessments of the activity concentration of different radionuclides in the environment, as well as the absorbed doses for species from different ecosystems, due to internal and external exposures, are needed. Brazil holds the second largest dog and cat population in the world and annually produces over 2 million tons of feed. The present work has investigated the radioactivity levels in commercial brands of dry dog and cat food, using high resolution gamma spectrometry. The results have shown activity concentrations for artificial radionuclides below the detector's Minimum Detectable Activity and also, low concentration levels for the natural radionuclides, varying from 0,9 ± 0,3 Bq/kg up to 5,1 ± 0,7 Bq/kg for 226 Ra, from 1,2 ± 0,4 Bq/kg up to 11,1 ± 1,0 Bq/kg for 232 Th and from 156 ± 7 Bq/kg up to 410± 19 Bq/kg for 40 K. In order to verify the mineral content in pet food, EDXRF technique was applied and, using multivariate statistics, correlations between the mineral and radionuclide content were verified. The good correlation observed between concentrations of 226 Ra, 232 Th and calcium could be associated with meat and bone our used in feed manufacturing. The internal dose for some organs were inferred by Monte Carlo method and the results were no higher than 1 μGy/day. In summary, results have shown that the activity levels found in the pet food are low enough to conclude that the brands evaluated carry no radiological risks for the animals that consume them. (author)

  18. Aerosol monitoring during work inside the 'object shelter': Analysis of dispersion and concentration for different work types

    International Nuclear Information System (INIS)

    Aryasov, P.; Nechaev, S.; Tsygankov, N.; Dmitrienko, A.

    2007-01-01

    Results of aerosol monitoring during work inside the object shelter (OS) are presented. Taking into account the fact that dispersion of the aerosol is one of the main factors affecting internal dose [Annals of the ICRP, ICRP Publication 66, Human Respiratory Tract Model for Radiological Protection, Pergamon Press, 1993], principal task of the investigation was the determination of the aerodynamic diameter (AD) distribution of the radioactive aerosol. Special attention was paid to transuranium elements' content in the aerosol since they are the major dose-producing radionuclides for the OS conditions. At present, work on stabilization of unstable constructions of the OS is in the active stage. Most of the work inside the OS leads to increased generation of radioactive aerosols. This work is carried out in the highly contaminated premises of the OS, where radioactive situation has been formed during the accident. Present work contains earliest results of the aerosol monitoring program for the period from September 2005 untill February 2006. Data obtained shows that for most types of work, radionuclides mainly located in the coarse aerosol fraction, activity median aerodynamic diameter (AMAD) range 8-12 μm. Work on the program continues at present time (actual data accumulation and analysis). Further widening of the program with the goal of type of material determination is described

  19. The influence of salt aerosol on alpha radiation detection by WIPP continuous air monitors

    International Nuclear Information System (INIS)

    Bartlett, W.T.; Walker, B.A.

    1996-01-01

    Alpha continuous air monitors (CAMs) will be used at the Waste Isolation Pilot Plant (WIPP) to measure airborne transuranic radioactivity that might be present in air exhaust or in work-place areas. WIPP CAMs are important to health and safety because they are used to alert workers to airborne radioactivity, to actuate air-effluent filtration systems, and to detect airborne radioactivity so that the radioactivity can be confined in a limited area. In 1993, the Environmental Evaluation Group (EEG) reported that CAM operational performance was affected by salt aerosol, and subsequently, the WIPP CAM design and usage were modified. In this report, operational data and current theories on aerosol collection were reviewed to determine CAM quantitative performance limitations. Since 1993, the overall CAM performance appears to have improved, but anomalous alpha spectra are present when sampling-filter salt deposits are at normal to high levels. This report shows that sampling-filter salt deposits directly affect radon-thoron daughter alpha spectra and overall monitor efficiency. Previously it was assumed that aerosol was mechanically collected on the surface of CAM sampling filters, but this review suggests that electrostatic and other particle collection mechanisms are more important than previously thought. The mechanism of sampling-filter particle collection is critical to measurement of acute releases of radioactivity. 41 refs

  20. Adaptive assay of pulmonary radioactive aerosol with an external detector

    International Nuclear Information System (INIS)

    Talmor, A.

    1989-12-01

    The applicability of the adaptive assay method was examined and then used to reduce the error caused by non-uniform spatial distribution. A computer program simulates adaptive assay of pulmonary aerosol within a standard man lungs, and compares its results with the results of static measurement. In the extreme hypothetical situation in which the aerosol is concentrated entirely in the left lung, and the static measurement is performed under the right arm, the errors obtained by calibration the static measurement on assumption of uniform spatial distribution, is as large as a factor 5 of the true value. In the same situation the adaptive assay result errs by less than 20%. In another situation, in which the aerosol is distributed in both lungs, and its concentration is higher in the pleura and near the back, the error obtained by calibrating the static measurement on the assumption of uniform spatial distribution, is as large as 30%, while the adaptive assay result errs by less than 2%. (author)

  1. Radioactivity Monitoring of the Irish Environment 2006

    International Nuclear Information System (INIS)

    Smith, V.; Dowdall, A; Fegan, M.; Hayden, E.; Kelleher, K.; Long, S.; McEvoy, I.; Somerville, S.; Wong, J.; Pollard, D.

    2007-10-01

    This report presents the results of the environmental radioactivity monitoring programme carried out by the Radiological Protection Institute of Ireland (RPII) in 2006. This programme aims to assess the exposure of the Irish population to artificial radioactivity in the environment, to review the temporal and geographical distribution of contaminating radionuclides and to maintain systems and procedures which would allow a rapid assessment of environmental contamination to be made in the event of a radiological emergency. Radioactivity is present in the environment due to natural processes, the testing of nuclear weapons in the atmosphere, past nuclear accidents such as that at Chernobyl in Ukraine and the routine discharge of radionuclides from nuclear installations. Liquid discharges from the British Nuclear Group reprocessing plant at Sellafield in Cumbria in the north-west of England, which are licensed by the UK Environment Agency, continue to be the dominant source of artificial radioactivity in the Irish marine environment. The key elements of the monitoring programme implemented by the RPII in 2006 included; assessment of ambient radioactivity based on measurements of radioactivity in air and of external gamma dose rate at permanent monitoring stations located throughout the country; assessment of levels of radioactivity in drinking water; assessment of levels of radioactivity in foodstuffs based on measurements of total diet, milk and various ingredients; assessment of levels of radioactivity in the Irish marine environment based on sampling and measurement of seawater, sediment, seaweed, fish and shellfish. The RPII monitored airborne radioactivity at ten stations located throughout the country. One of these stations is equipped with a high volume sampler, which allows concentrations of caesium-137 to be measured; another is equipped to detect the presence of the gas krypton-85. This gas is released into the environment primarily as a result of the

  2. Influence of weather conditions on natural radioactivity

    International Nuclear Information System (INIS)

    Simion, Florin; Simion, Elena; Cuculeanu, Vasile; Mihalcea, Ion

    2011-01-01

    This paper presents the dependence of the natural radioactivity on atmospheric weather conditions: air temperature, atmospheric pressure, wind speed, atmospherical precipitations and relative humidity. The values used in the paper were taken from the environmental radioactivity monitoring in Botosani city, Romania, as measured by the Environmental Radioactivity Surveillance Station. Daily global measurements of atmospheric deposition beta and atmospheric aerosols as well were carried out, including the indirect determination of radon and thoron, and the absorbed gamma dose rate in air, as well. Sampling and measurement frequency depended on the type of sample analyzed as follows: atmospheric deposition were taken daily, atmospheric aerosols were collected 4 times/day, with a sampling interval of 5 hours while the air absorbed dose rate was determined at a hourly rate. The coefficient of multiple correlation between the type of analysis and weather conditions, was determined. By using multiple linear regression it was highlighted the natural radioactivity dependence on the atmospheric conditions and meteorological parameters by a mathematical expression that can be used to determine missing values in a time series of measured data. By predicting the measured values our procedure can be considered as a validation process of the measurement accuracy

  3. Radioactive contamination of the Guatemalan marine environment

    International Nuclear Information System (INIS)

    Perez-Sabino, J.F.; Oliva de Sandoval, B.E.; Orozco-Chilel, R.M.; Aguilar-Sandoval, E.

    1999-01-01

    As part of the IAEA TC project GUA/2/005 'Radioactivity and Contamination of the Marine Environment in Guatemala', concentrations of artificial and natural radionuclides have been determined in marine water and sediments, giving important information to establish the base line of the natural radioactivity and the radioactive contamination in this area that not have been studying

  4. Artificial radioactivity in Carlingford Lough

    International Nuclear Information System (INIS)

    Mitchell, P.I.; Vives i Batlle, J.; Ryan, T.P.; Caulfield, J.J.; Larmour, R.A.; Ledgerwood, F.K.

    1992-09-01

    The principal objective of this study was to assess whether radioactivity concentrations in a wide range of environmental materials from the Lough were enhanced above general levels found elsewhere along the east and north-east coasts of Ireland. Other objectives included an examination of gamma dose rates in air over inter-tidal sediments throughout the Lough and an examination of coastal soils to determine the extent of sea-to-land transfer of plutonium and , by inference, americium

  5. Radioactivity Monitoring of the Irish Environment 2009

    International Nuclear Information System (INIS)

    McGinnity, P.; Currivan, L.; Dowdall, A.; Fegan, M.; Hanley, O.; Kelleher, K.; McKittrick, L.; Somerville, S.; Wong, J.; Pollard, D.

    2010-12-01

    This report presents the results of the environmental radioactivity monitoring programme carried out by the Radiological Protection Institute of Ireland (RPII) during 2009. The RPII has routinely monitored levels of radioactivity in the environment since 1982 and this is the latest in the RPII's series of environmental monitoring reports. The RPII reviews and updates its environmental programme annually so as to ensure it remains relevant and continues to focus on the most important sources of radioactivity in the environment. The principal aims of the RPII's monitoring programme are; to assess the level of radioactivity to which the Irish population is exposed as a result of radioactivity in the environment; to study trends and establish the geographical distribution of contaminating radionuclides so as to better understand the long term behaviour of artificial radioactivity in the food chain and the environment; to ensure that any increase in radiation levels resulting from an accidental release of radioactivity to the environment is detected and assessed rapidly. During 2009 radioactivity was measured in a wide range of foods and environmental materials including: air, water, milk, seafood, foodstuffs and complete meals. The most significant source of artificial radioactivity in the Irish marine environment is the discharge of low level liquid radioactive waste from the Sellafield Nuclear Fuel Reprocessing Plant on the north east coast of England. In order to assess the exposure arising from the source extensive sampling of fish and shellfish landed at ports along the north east coast of Ireland is undertaken. The most exposed group of individuals to discharges from Sellafield have been identified as commercial oyster and mussel farmers working along the north east coastline and their families. Manmade radioactivity is also present in the terrestrial environment due primarily to residual global fallout arising primarily from atmospheric testing of nuclear

  6. Radioactivity Monitoring of the Irish Environment 2008

    International Nuclear Information System (INIS)

    Fegan, M.; Currivan, L.; Dowdall, A.; Hanley, O.; Hayden, E.; Kelleher, K.; Long, S.; McKittrick, L.; Somerville, S.; Wong, J.; Pollard, D.

    2010-01-01

    This report presents the results of the environmental radioactivity monitoring programme carried out by the Radiological Protection Institute of Ireland (RPII) during 2008. The RPII has routinely monitored levels of radioactivity in the environment since 1982 and this is the latest in the RPII's series of environmental monitoring reports. The RPII reviews and updates its environmental programme annually so as to ensure it remains relevant and continues to focus on the most important sources of radioactivity in the environment. The principal aims of the RPII's monitoring programme are; to assess the level of radioactivity to which the Irish population is exposed as a result of radioactivity in the environment; to study trends and establish the geographical distribution of contaminating radionuclides so as to better understand the long term behaviour of artificial radioactivity in the food chain and the environment; to ensure that any increase in radiation levels resulting from an accidental release of radioactivity to the environment is detected and assessed rapidly. During 2008 radioactivity was measured in a wide range of foods and environmental materials including: air, water, milk, seafood, foodstuffs and complete meals. The most significant source of artificial radioactivity in the Irish marine environment is the discharge of low level liquid radioactive waste from the Sellafield Nuclear Fuel Reprocessing Plant on the north east coast of England. In order to assess the exposure arising from the source extensive sampling of fish and shellfish landed at ports along the north east coast of Ireland is undertaken. The most exposed group of individuals to discharges from Sellafield have been identified as commercial oyster and mussel farmers working along the north east coastline and their families. Manmade radioactivity is also present in the terrestrial environment due primarily to residual global fallout arising primarily from atmospheric testing of nuclear

  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. 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

  9. Fission product vapour - aerosol interactions in the containment: simulant fuel studies

    International Nuclear Information System (INIS)

    Beard, A.M.; Benson, C.G.; Bowsher, B.R.

    1988-12-01

    Experiments have been conducted in the Falcon facility to study the interaction of fission product vapours released from simulant fuel samples with control rod aerosols. The aerosols generated from both the control rod and fuel sample were chemically distinct and had different deposition characteristics. Extensive interaction was observed between the fission product vapours and the control rod aerosol. The two dominant mechanisms were condensation of the vapours onto the aerosol, and chemical reactions between the two components; sorption phenomena were believed to be only of secondary importance. The interaction of fission product vapours and reactor materials aerosols could have a major impact on the transport characteristics of the radioactive emission from a degrading core. (author)

  10. Medical imaging was boosted by the discovery of artificial radioactivity; L'imagerie medicale revelee par la radioactivite

    Energy Technology Data Exchange (ETDEWEB)

    Demarthon, F.; Dupuy-Maury, F.; Donnars, O

    2002-08-01

    This article draws the history of medical imaging since the discovery of artificial radioactivity in 1934. The author reviews the PET (positron emission tomography) and MRI (magnetic resonance imaging) technologies and presents the recent progress in neuro-sciences that have been made possible by using these 2 technologies. Brain imaging has allowed to show: - the impact of emotions on logical mental processes and on mental performances, - the management of memory in the brain of talented quick reckoners, - the degeneration of neurons, and - the link between autism and the presence of structural and functional anomalies in the brain. (A.C.)

  11. Radioactive contamination of the Guatemalan marine environment

    Energy Technology Data Exchange (ETDEWEB)

    Perez-Sabino, J F; Oliva de Sandoval, B E; Orozco-Chilel, R M; Aguilar-Sandoval, E [Universidad de San Carlos de Guatemala, Facultad de Ciencias Quimicas y Farmacia, Unidad de Analisis Instrumental, Guatemala C.A. (Guatemala)

    1999-07-01

    As part of the IAEA TC project GUA/2/005 `Radioactivity and Contamination of the Marine Environment in Guatemala`, concentrations of artificial and natural radionuclides have been determined in marine water and sediments, giving important information to establish the base line of the natural radioactivity and the radioactive contamination in this area that not have been studying 4 refs, 1 fig., 4 tabs

  12. Ambient radioactivity levels and radiation doses. Annual report 2014; Umweltradioaktivitaet und Strahlenbelastung. Jahresbericht 2014

    Energy Technology Data Exchange (ETDEWEB)

    Trugenberger-Schnabel, Angela; Loebke-Reinl, Angelika; Peter, Josef (comps.) [Bundesamt fuer Strahlenschutz, Salzgitter (Germany)

    2016-08-15

    The annual report 2014 on ambient radioactivity levels and radiation doses covers the following topics: (1) Actual data and their evaluation: natural environmental radioactivity, artificial environmental radioactivity, occupational radiation exposure, radiation exposures from medical applications, handling of radioactive materials and sources of ionizing radiation, non-ionizing radiation. (2) Fundamentals and general information: legal basis and explanations, basic information on natural environmental radioactivity, basic information on artificial radioactivity in the environment, basic information on occupational radiation exposure, basic information on radiation exposures from medical applications, basic information on the handling of radioactive materials and sources of ionizing radiation, basic information on non-ionizing radiation. (3) Tables.

  13. Measurement of the deposition of aerosol particles to skin, hair and clothing

    International Nuclear Information System (INIS)

    Bell, K.F.

    1999-01-01

    In the event of a nuclear accident, there are several routes whereby human populations may receive a radioactive dose from material released to the environment. The dose from radioactive aerosol deposited onto the surfaces of the human body has previously been estimated by assuming that aerosol deposition velocities (defined as the flux of aerosol onto a surface divided by the aerosol concentration above the surface) onto human body surfaces are similar to the values for inanimate surfaces. However, Jones (1990) modelled the effects on health of fallout material deposited on skin and clothing and found that the number of early deaths from skin dose was sensitively dependent on aerosol deposition velocity. He also pointed out that there was a lack of experimentally derived data on aerosol deposition velocities to human body surfaces and that the above mentioned assumption may not be valid. The purpose of the present work is to measure aerosol deposition velocities onto human body surfaces, the resultant data to allow more accurate nuclear accident consequence modelling. Aerosol deposition velocities onto human body surfaces in simulated indoor conditions have been measured by releasing tracer aerosols of three mean particle diameters (2.6, 6.2 and 9.2μm) into a test chamber containing volunteers. The skin, hair and clothing of the volunteers were sampled and analysed for deposited aerosol by Neutron Activation Analysis. Aerosol deposition velocities onto skin in the range 1.3 - 15 x 10 -3 ms -1 were recorded, values which are approximately an order of magnitude higher than the equivalent values onto the floor of the test room. These values suggest that the exposure route of radioactive aerosol particles deposited on the skin may be more significant than hitherto had been assumed. The possible mechanisms leading to this relatively high deposition were investigated experimentally and the results suggested that a combination of factors such as the body's electrostatic

  14. Development of artificial radioactivity in the French environment during the past 50 years and related doses; effect of the current operation of nuclear facilities

    International Nuclear Information System (INIS)

    Renaud, Ph.; Roussel-Debet, S.

    2010-01-01

    The activities of artificial radionuclides in the environment have being strongly decreasing since 50 years. Nowadays the activities of 3 H and 14 C widely predominate, but they cannot be still considered as artificial radionuclides, except nearby the nuclear installations where they constitute the most abundant radioactive releases. In terrestrial environment this influence is limited to the surroundings of 5 sites, although most of nuclear sites and nuclear medical centers are involved in the contamination of the aquatic environment downstream the releases and in the Channel. Since 1987 the doses to the French population have been mainly induced by 14 C and 137 Cs. (author)

  15. LWR aerosol containment experiments (LACE) program and initial test results

    International Nuclear Information System (INIS)

    Muhlestein, L.D.; Hilliard, R.K.; Bloom, G.R.; McCormack, J.D.; Rahn, F.J.

    1985-01-01

    The LWR aerosol containment experiments (LACE) program is described. The LACE program is being performed at the Hanford Engineer Development Laboratory (operated by Westinghouse Hanford Company) and the initial tests are sponsored by EPRI. The objectives of the LACE program are: to demonstrate, at large-scale, inherent radioactive aerosol retention behavior for postulated high consequence LWR accident situations; and to provide a data base to be used for aerosol behavior . Test results from the first phase of the LACE program are presented and discussed. Three large-scale scoping tests, simulating a containment bypass accident sequence, demonstrated the extent of agglomeration and deposition of aerosols occurring in the pipe pathway and vented auxiliary building under realistic accident conditions. Parameters varied during the scoping tests were aerosol type and steam condensation

  16. Radioactivity level of airplane to Guangzhou Baiyun international airport during the Fukushima Daiichi nuclear power plant accident

    International Nuclear Information System (INIS)

    Song Haiqing; Chen Wentao; Cheng Xiaobo; Liao Tong; Deng Fei; Chen Fuliang; Zhang Yanjin; Li Lingjuan; Liang Guiyuan; Wu Guibiao

    2014-01-01

    The radioactivity level of airplanes to Guangzhou Baiyun International Airport (GBIAC) during the Fukushima Daiichi nuclear power plant accident was monitored by Guangdong Environmental Radiation Monitoring Center (GERC) on March 15 and 16, 2011. The artificial radionuclide "1"3"1I, "1"3"4Cs, "1"3"7Cs, "l"3"6Cs, "1"3"2I, "1"3"2Te were detected in the wipe samples of the outer surface of airplanes from Japan to GBIAC. The radioactivity ration of "1"3"7Cs/"1"3"4Cs was calculated as (1.12 ± 0.06) in the wipe samples, which similar to the result in the wipe sample of the outer surface of airplanes from Japan to Hangzhou airport obtained by Zhejiang Province Environmental Radiation Monitoring Center (l.lO ± 0.08), but slightly higher than results in the aerosol monitoring at Guangzhou (0.99 ± 0.30) and Shenzhen (0.94 ± 0.30) by GERC, the data (0.83) published by Japan Nuclear and Industrial Safety Agency (NISA) and the result (1.00 ± 0.13) measured by Tokyo Electric Power Company. A slight radioactive contamination was detected on the surface of outer airplanes and internal cabin. The practice suggested that the wipe sample of the outer surface of airplane was a fast , simple and sensitive approach for emergency monitoring of radioactive contamination. (authors)

  17. Aerosol delivery in intubated, mechanically ventilated patients

    International Nuclear Information System (INIS)

    MacIntyre, N.R.; Silver, R.M.; Miller, C.W.; Schuler, F.; Coleman, R.E.

    1985-01-01

    To study the effects of respiratory failure and mechanical ventilation on aerosol delivery to the lungs, nuclear scans were performed after aerosolization of 5 to 9 mCi of Tc-99m diethylenetriamine pentaacetic acid in seven stable, intubated, and mechanically ventilated patients. The radioactivity reaching the lungs was 2.9 +/- .7% (mean +/- SD) of the administered dose, an amount significantly less than that in three healthy nonintubated subjects and also less than what would be expected in nonintubated subjects from other published reports. A subsequent study was performed in 15 additional mechanically ventilated patients who were receiving aerosolized bronchodilators through their endotracheal tube. In these patients, heart rate and lung mechanical function values before and after treatment were not significantly different. It is concluded from these studies that aerosol delivery in mechanically ventilated patients is significantly reduced and that this is probably due to a combination of suboptimal breathing pattern, intrinsic airway disease, and the endotracheal tube functioning as both a site for aerosol deposition through impaction as well as a barrier to gastrointestinal absorption

  18. Application of artificial radioactive tracers for groundwater flow

    International Nuclear Information System (INIS)

    Hamza, M.S.; Aly, A.I.M.; Swailem, F.M.; Nada, A.A.; Awad, M.A.

    1989-01-01

    In this work, the groundwater velocity was estimated by applying radioactive tracer techniques: the single well and the multiple well methods. In the first single well method, radioactive iodine-131 was injected in the well and the radioactivity was monitored with time. The groundwater flow was estimated as a function of the concentration dilution factor of the tracer taking into consideration the permeability of the filter screen and the aquifer. The second method (the multiple well technique) is based on direct measuring of the period of time the tracer needs to disperse from the injection well to one of receptor well arranged in a circle around the injection. The latter method was found to be more accurate and reliable and has also the advantage of determining the groundwater velocity and direction of flow as well. The limitations of the single well technique are discussed and a detailed comparison between single and multi-well techniques is given

  19. Environmental radioactivity in the antarctic station

    International Nuclear Information System (INIS)

    Gonzalez, S.; Osores, J.; Martinez, J.; Lopez, E.; Jara, R.

    1998-01-01

    Study about environmental radioactivity in the Peruvian antarctic station Machu Pichu they were carried out during the last three periods to the southern summer. The objective of the project it is to evaluate environmental component in order to elaborate a study it base on the levels background radioactivity and artificial in the antarctic region

  20. Radioactive monitoring of the marine environment

    International Nuclear Information System (INIS)

    Bologa, A. S.

    1991-01-01

    Radioactivity monitoring of marine environment was required by the development of nuclear power and the worldwide use of ionizing radiations in many different activities. Both natural and artificial radioactivity play an important role in marine ecology and human health. In respect of this, three major facts prevail, namely: the fallout, the proximity of Danube River and the future nuclear power production. Spatial and temporal monitoring of marine radioactivity along the Romanian Black Sea shore has been systematically performed in Romanian Marine Research Institute in close cooperation with Institute of Meteorology and Hydrology since 1981. Marine emerged and submerged sediments, coastal and offshore sea water, macroalgae, invertebrates and fish of Danube mouths and/or along the coast are monitored for natural and artificial radioactivity by means of gross beta measurements and gamma spectrometry. Concentrations of radionuclides such as: K-40, Cs-134 and Cs-137 in abiotic and biotic samples, environmental distribution coefficients and concentration factors (CFs) as well as experimentally derived CFs in marine biota as radioecological bioindicators are assessed and stored in a national data base. (author)

  1. Airborne concentrations of radioactive materials in severe accidents

    International Nuclear Information System (INIS)

    Ross, D.F. Jr.; Denning, R.S.

    1989-01-01

    Radioactive materials would be released to the containment building of a commercial nuclear reactor during each of the stages of a severe accident. Results of analyses of two accident sequences are used to illustrate the magnitudes of these sources of radioactive materials, the resulting airborne mass concentrations, the characteristics of the airborne aerosols, the potential for vapor forms of radioactive materials, the effectiveness of engineered safety features in reducing airborne concentrations, and the release of radioactive materials to the environment. Ability to predict transport and deposition of radioactive materials is important to assessing the performance of containment safety features in severe accidents and in the development of accident management procedures to reduce the consequences of severe accidents

  2. Degraded core accidents: review of aerosol behaviour in the containment of a PWR

    International Nuclear Information System (INIS)

    Nichols, A.L.; Walker, B.C.

    1981-09-01

    Low probability-high consequence accidents have become an important issue in reactor safety studies. Such accidents would involve damage to the core and the subsequent release of radioactive fission products into the environment. Aerosols play a major role in the transport and removal of these fission products in the reactor building containment. The aerosol mechanisms, computer modelling codes and experimental studies used to predict aerosol behaviour in the containment of a PWR are reviewed. There are significant uncertainties in the aerosol source terms and specific recommendations have been made for further studies, particularly with respect to code development and high density aerosol-fission product transport within closed systems. (author)

  3. Doses of radiation from natural and artificial radioactive sources. [In German

    Energy Technology Data Exchange (ETDEWEB)

    Franzen, L F; Myszynski, G; Wiesenack, G

    1957-01-01

    Only since quite recently has man been subjected to irradiation which, as the result of medical and industrial development has been added to the radiation from natural sources. According to the investigations quoted artificial radiation accounts for 20 to 25 per cent of the total radiation level. Atomic test explosions have so far only made an insignificant contribution. The same can still be said of the industrial application of nuclear energy which is still in its infancy. It has been estimated that people living in Europe will over a period of 30 years be subjected to a total dose of radiation from 2500 to 4000 mr. Of this total dose received in 30 years about 750 to 850 mr will be contributed by medical and industrial appurtenances, the overwhelming share of 600 to 700 mr being the result of medical x-ray diagnosis. The atmospheric radioactivity has been estimated (incl. rainfall, etc.) at 20 to 30 mr over a period of 30 years and will therefore not represent any hazards as far as external, direct radiation is concerned. The possible absorption by and accumulation of radiation substances in the body must, however, be carefully studied and special consideration must be given to fission products with a long half-life.

  4. On the dynamics of fine aerosols artificially produced. Application to the atmosphere

    International Nuclear Information System (INIS)

    Perrin, Marie-Line

    1980-01-01

    We take advantage of the developments of a new method of measurement, using a diffusion battery, to analyse the evolution of ultra-fine particles generated as a result of gas-phase reactions (radiolysis and photolysis). The evolution of aerosols instantaneously produced by radiolysis of gaseous impurities is studied and a theoretical model from the coagulation equation's resolution is shown to well describe the phenomena. Experiments with aerosols continuously produced by photo-oxidation of SO 2 show the effect of the condensable molecules production rate and the preexisting aerosol, on the subsequent growth of the primary embryos. Different theoretical models are qualitatively and quantitatively verified. Our experiments are then extended to 'in situ' measurements in urban and marine atmospheres, and in every case, we quantitatively determine the importance of each intervening process, namely nucleation, coagulation and condensation. (author) [fr

  5. Interaction of radon progeny with atmospheric aerosols

    International Nuclear Information System (INIS)

    Morawska, Lidia

    1994-01-01

    The radiological health hazard due to the airborne radon progeny depends on three factors (i) radon concentration in the air, (ii) radon progeny concentration, and (iii) active particle size distribution. Conclusions as to the health hazard cannot be drawn without full understanding of the interaction mechanisms between radon progeny and atmospheric aerosols. The aim of this work was to study the interaction mechanisms between radon progeny, natural environmental aerosols and environmental tobacco smoke (ETS). The experiments were performed under controlled laboratory conditions of radon concentration (1.85 and 3.70 Bq m -3 ), relative humidity (35, 50, 75 and 95%) and ETS generation. The size distribution of radioactivity carrying aerosols was measured using a wire screen diffusion battery system and size distribution of all airborne aerosols using a differential mobility particle sizer. The paper presents and discusses the results of activity size distribution and radon progeny concentration measurements for different environmental conditions. 7 refs., 2 tabs

  6. Problems presented by the filtration and sampling of aerosols in the atomic energy programme; Problemes poses par la filtration et le prelevement des aerosols dans le cadre de l'energie atomique

    Energy Technology Data Exchange (ETDEWEB)

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

    1959-07-01

    The maximum permissible limits for radioactive aerosols are much lower than those for aerosols encountered in the non-nuclear industries. These limits depend on numerous factors such as: nature of the radiation, half-life, etc. The radioactive aerosols can be prepared by various methods. The filtering of the air in high activity laboratories or in plutonium treatment factories necessitates an installation consisting of: - aspiration filters, - extraction filters of very high efficiency (those used for {alpha} emitter cells: designed to be replaced without incurring contamination risks; those used for {gamma} emitter cells: designed to be replaced by remote control). The filtering in nuclear reactors is also effectuated by filter papers: - the G1 reactor with open circuit: the air coolant is entirely filtered at the entry and on leaving; - the G2, G3 and EDF1 reactors with closed circuits: filtering under pressure of a small portion of the coolant gas. (author) [French] Les limites maxima permises des aerosols radioactifs sont beaucoup plus faibles que celles des aerosols rencontres dans l'industrie classique. Elles dependent de nombreux facteurs tel que: nature du rayonnement, periode radioactive, etc... La formation des aerosols radioactifs est de nature diverse. La filtration des laboratoires de haute activite, ou d'usines d'elaboration de plutonium conduit a des types d'installations comportant: - des filtres d'aspiration; - des filtres d'extraction a rendement extremement eleve (type pour cellules emettrices {alpha} concu pour etre change sans risque de contamination, type pour cellules emettrices {gamma}: concu pour etre change a distance) La filtration des reacteurs nucleaires sont egalement effectuee par des papiers filtres: - reacteur G1 a circuit ouvert: air de refroidissement totalement filtre a l'aspiration et a l'extraction; - reacteurs G2, G3, EDF1: a circuit ferme: filtration sous pression d'une faible partie du gaz de refroidissement. (auteur)

  7. Device for contaminating laboratory animals by inhalation of radioactive aerosols

    International Nuclear Information System (INIS)

    Lutz, M.; Rouvroy, H.

    1966-01-01

    The contamination enclosure is made up of a sphere to which are attached an aerosol generator, containers adapted to the animals to be used, and the atmospheric sampling system. The sphere is placed in a protective glove-box, the latter being itself protected by an introduction chamber fitted with locking access lids. A detailed description is given of the working principle. As an example, some results are given concerning the contamination of rats by a plutonium oxide aerosol: characteristics of the powder (mean diameter 0.50 μ - standard deviation: 1.4), examination and evolution of the atmospheric activity as a function of time, evaluation of the retention by the lungs by means of histological and autoradiographic examinations. (authors) [fr

  8. Intercomparison test of various aerosol measurement techniques

    International Nuclear Information System (INIS)

    Cherdron, W.; Hassa, C.; Jordan, S.

    1984-01-01

    At the suggestion of the CONT group (Containment Loading and Response), which is a subgroup of the Safety Working Group of the Fast Reactor Coordinating Committee, a group of experts undertook a comparison of the techniques of sodium aerosol measurement used in various laboratories in the EC. The following laboratories took part in the exercise: CEN-Mol (Belgium), CEA-Cadarache (France), CEA-Fontenay-aux-Roses (France), KfK-Karlsruhe (Federal Republic of Germany), ENEA-Bologna (Italy), and UKAEA-Winfrith (United Kingdom). The objective of the aerosol measurement workshop was to assess the applicability and reliability of specific aerosol measuring instruments. Measurements performed with equipment from the participating laboratories were evaluated using a standard procedure. This enabled an estimate of the accuracy of the experimental data to be provided for the verification of aerosol codes. Thus these results can be used as input for the physical modelling of aerosol behaviour, and the work reported here is a contribution to the definition of the radioactive source term for severe accidents in LMFBRs. The aerosol experts participating in the exercise agreed to concentrate on the techniques of measuring aerosol particle size distributions. The tests were performed at the FAUNA test facility using the aerosol loop. A sodium spray fire, which provides a continuous aerosol source of variable concentration, was produced under open-loop conditions in this facility. Although the primary objective of the workshop was to determine the particle size distributions of the aerosols, measurements of the sodium mass concentration were also made

  9. Aerosol measurements and nuclear accidents: a reconsideration, report of the round table discussion

    International Nuclear Information System (INIS)

    Raes, F.

    1988-01-01

    Radioactivity Environmental Monitoring (REM) is commonly divided into routine and emergency monitoring. Routine REM must demonstrate the adequacy of controls on releases as well as the compliance with radiological standards. It should also be able to give an early warning in case of abnormal concentrations, so that emergency REM may be initiated promptly. It should be clear, however, that stack monitoring and other in-plant measurements are the primary information sources for abnormal conditions. Emergency REM should rapidly assess the extent of an accident and provide the information needed for taking countermeasures. The collection of in-depth information on environmental processes for model validation is usually considered as an additional benefit of both routine and emergency REM. In discussing techniques for measuring radioactive aerosols, in particular the need for new and more sophisticated techniques, one must consider the objectives of REM, define how much weight should be given to each of them, and investigate whether new techniques might help in meeting the objectives. The opinions of the experts are organized into three chapters: the first compiles experiences and opinions about radioactive aerosol monitoring and defines the experimental needs for such monitoring with respect to early warning and early assessment in case of nuclear accidents; the second chapter discusses radioactive aerosol monitoring from the point of view of the scientist who wants to increase or validate his knowledge about the behaviour of radionuclides in the atmosphere; the third chapter reviews recent developments in field of aerosol and nuclear metrology and their interest for nuclear safety. Each chapter ends with a number of conclusions and recommendations

  10. Realization of nuclear track filters and their applications to the study of environmental aerosol samples

    International Nuclear Information System (INIS)

    Guo Shilun

    1993-01-01

    Detailed study of the behaviours of radon decay products requires the knowledge of environmental aerosols. A combination of devices and instruments have been tested to be superior in study of aerosol characteristics. Nuclear track filters and cascade track filter impactor are basic devices, which bring the functions of α -spectrometer, scanning electron microscope and electron microprobe into full play. This paper describes how to use these devices and instruments to collect aerosols, to determine aerosol radioactivity, size distribution and elemental compositions and to determine the concentration of aerosols in air as a function of aerosol sizes, which are important parameters in dominating the interactions between aerosol and radon decay products. (author). 15 refs, 7 figs

  11. studies on the fixation of chemical and radioactive contaminants by natural and artificial compounds

    International Nuclear Information System (INIS)

    Mourad, G.A.M.

    2006-01-01

    the main objective of the work presented in this is to study the adsorption of U(VI), Cr(VI) and Gd (lll) from aqueous medium using modified sorel's cement as artificial adsorbents. the thesis is classified into three chapters; namely ,introduction ,experimental and results and discussion. the first chapter, i ntroduction , includes chemical and radioactive contaminant, some aspects of the properties and aqueous chemistry of uranium, chromium and gadolinium . the separation of different pollutant and their methods of separation based on the types of adsorbents, and the theoretical background of adsorption isotherms, kinetics and ion diffusion as well as literature survey which is related to the present work are given.the second chapter, e xperimental , contains the different materials employed, their chemical purity, and a detailed description for instruments used are given.the third chapter. r esults and discussion i ncludes the experimental results obtained and their interpretation .this chapter is classified into three main parts; namely, characterization, equilibrium and kinetic investigations

  12. Radioactivity and Environment

    International Nuclear Information System (INIS)

    Sanchez Leon, J.G.

    1993-01-01

    Radioactivity is one of the most studied natural phenomena. Most of irradiation suffered by the human being is produced by natural sources. The second source in order of importance is nuclear medicine. The average level of radiation received by the man is 2.4 mSv/year and this value can be modified naturally in 20-30%. The author provides a review on radioactivity sources like natural (cosmic rays, extraterrestrial radiation, internal earth radiation, radon) and artificial (Nuclear explosions, professional exposure, nuclear medicine, nuclear power plants and accidents)

  13. Characterisation of Aerosols from Simulated Radiological Dispersion Events

    NARCIS (Netherlands)

    Di Lemma, F.G.

    2015-01-01

    The research described in this thesis aims at improving the evaluation of the radiaoctive aerosol release from different Radiological Dispersion Events (RDE's), such as accidents and sabotage involving radioactive and nuclear materials. These studies help in a better assessment of the source term as

  14. Measurement of radioactivity in air at the linear accelerator of Kyoto University reactor facility

    International Nuclear Information System (INIS)

    Ikebe, Yukimasa; Shimo, Michikuni

    1976-01-01

    It is well-known that the induced activities from a number of nuclides are generated in air during the operation of high energy accelerators. Of these, measurements were performed with the linear accelerator of Kyoto University reactor facility for the purpose of the clarification of the production mechanism and behavior of radioactive aerosols. The concentration in air and the size distribution of 13 N aerosols which have aerosols as the carrier among 13 N produced by the γ-n reaction of 14 N were measured with filter packs and by diffusion method, respectively. The density of number and size distribution of non-radioactive aerosols were measured to understand the production mechanism and behavior of 13 N aerosols. For the aerosol number density, Aitken nucleus number was measured with a Pollak counter. The results obtained show that (1) under the operating condition of the linear accelerator at that measurement time, 13 N aerosol concentration was (2 to 50) x 10 -13 Ci/cm 3 while 13 N gas component concentration was (1 to 25) x 10 -12 Ci/cm 3 , i.e. the ratio was approximately 1 : 10 (2) the average size of 13 N aerosols was 0.01 to 0.04 μm, and it was found that there was positive correlation to relative humidity; (3) during the operation of the accelerator, the generation of aerosols 10 to 100 times as much as the background level was observed. The size distribution of aerosols showed a peak around 0.01 μm; and others. Examination was carried out regarding a 13 N aerosol production model based on the sticking of aerosol-free 13 N to aerosols. (Wakatsuki, Y.)

  15. ''Inhalation lung imaging with radioactive aerosols and gases''

    International Nuclear Information System (INIS)

    Taplin, G.V.; Chopra, S.K.

    1977-01-01

    Lung imaging procedures, performed after the inhalation of /sup 99m/Tc labeled aerosols, 133 Xe and /sup 81m/Kr gases, were used to visualize the sites of airway obstruction and regional abnormalities of ventilatory function in normal volunteers, patients with obstructive airway disease, and pulmonary embolism suspects. Comparisons were made of three methods regarding their functional significance, diagnostic merits, and limitations. A new nebulizer-radioaerosol delivery system is described

  16. First artificial radionuclides for Czechoslovakia after Word War II. Pt. 1

    International Nuclear Information System (INIS)

    Tesinska, Emilie

    2014-01-01

    This first contribution in the 2-part series describes the following topics: Discovery of artificial radioactivity and first artificial radionuclides; Czechoslovak reflection of the development over the world; Opportunities for obtaining artificial radioisotopes from the USA; Response to the US offer by Czechoslovak physicians; and Steps taken by the Ministry of Health. (orig.)

  17. Calculation Of Aerosol Transport Efficiency For The Airborne Radioiodine Monitoring System - ''RIS125''

    International Nuclear Information System (INIS)

    Kravchik, T.; Levinson, L.; Mazor, Y.; Dolev, E.; German, U.

    1999-01-01

    Radioactive iodine is a typical fission product in nuclear power reactors. Of the many iodine isotopes that can be generated in nuclear reactors only four are considered as radiobiological significant. These are: 125 1 (T 1/2 =60 days), '1 31 I (T 1/2 =8d), 133 I (T 1/2 =21h) and I35 I (T 1/2 7h). The chemical forms that have been identified in heavy water reactors are I 2 (elemental), organic iodides (CH 3 I), Inorganic iodides (HOI, HI) and LiI. Radioiodine is, generally, released as a gas but can be adsorbed on air particulates to form radioiodine contained aerosols. Therefore. its monitoring has to include both gas and aerosol sampling. A new monitoring system, RIS (Radioactive iodine Sampler), has been developed at the NRCN to monitor radioactive iodine (gas and aerosol) on-line in workplaces. This system samples radioiodine at a 60 L/min rate through a transport line connected to a filter holder. The filter consists of a cartridge containing activated charcoal with TEDA for iodine gas adsorption with a membrane for aerosols' retention in from of it. The radioiodine filter cartridge (F and J product code: TE2C) has a diameter of 2 1/4 inch and height of 1 inch . The gas adsorbent is coconut shell carbon type activated charcoal with 5% (by weight) TEDA impregnation and has 30x50 mesh size. This paper presents the aerosols' sampling characteristics of the RIS system including their transport in the sampling line and filter holder. The adsorption of iodine gas on the transport system components is negligible

  18. Radioactivity in the environment

    International Nuclear Information System (INIS)

    Fernandez Niello, Jorge

    2005-01-01

    The book summarizes general concepts on radiation, nuclear structure, radioactivity and the interaction of the nuclear radiation with matter. It describes also the basic principles of radio dosimetry. Natural and artificial sources of radiation are reviewed as well as the effects of radiation in man. Medical and industrial applications of ionizing radiation and the pollution produced by the discharge of radioactive materials are outlined. A short review is made of the safety rules and the regulations concerning the protection of the environment [es

  19. Aerosol retention in the flooded steam generator bundle during SGTR

    International Nuclear Information System (INIS)

    Lind, Terttaliisa; Dehbi, Abdel; Guentay, Salih

    2011-01-01

    Research highlights: → High retention of aerosol particles in a steam generator bundle flooded with water. → Increasing particle inertia, i.e., particle size and velocity, increases retention. → Much higher retention of aerosol particles in the steam generator bundle flooded with water than in a dry bundle. → Much higher retention of aerosol particles in the steam generator bundle than in a bare pool. → Bare pool models have to be adapted to be applicable for flooded bundles. - Abstract: A steam generator tube rupture in a pressurized water reactor may cause accidental release of radioactive particles into the environment. Its specific significance is in its potential to bypass the containment thereby providing a direct pathway of the radioactivity from the primary circuit to the environment. Under certain severe accident scenarios, the steam generator bundle may be flooded with water. In addition, some severe accident management procedures are designed to minimize the release of radioactivity into the environment by flooding the defective steam generator secondary side with water when the steam generator has dried out. To extend our understanding of the particle retention phenomena in the flooded steam generator bundle, tests were conducted in the ARTIST and ARTIST II programs to determine the effect of different parameters on particle retention. The effects of particle type (spherical or agglomerate), particle size, gas mass flow rate, and the break submergence on particle retention were investigated. Results can be summarized as follows: increasing particle inertia was found to increase retention in the flooded bundle. Particle shape, i.e., agglomerate or spherical structure, did not affect retention significantly. Even with a very low submergence, 0.3 m above the tube break, significant aerosol retention took place underlining the importance of the jet-bundle interactions close to the tube break. Droplets were entrained from the water surface with

  20. Preparation of denatured sup(99m)Tc labeled HSA aerosols of different median diameters for various imaging studies

    Energy Technology Data Exchange (ETDEWEB)

    Raghunath, B.; Kotrappa, P.; Soni, P.S.; Ganatra, R.D. (Bhabha Atomic Research Centre, Bombay (India))

    1982-02-01

    The preparation of denatured sup(99m)Tc-labelled human serum albumin (HSA) aerosols of different median diameters is described using the BARC (Bhabha Atomic Research Centre) dry aerosol generation and delivery system. The applications of these radioactive aerosols are demonstrated in aerosol scintigraphy of lungs, mucociliary movement studies and lymphoscintigraphy in rabbits. It is concluded that the BARC system gives a simplified, rapid and versatile procedure for generation of denatured volume tagged HSA aerosols for a variety of clinical applications.

  1. Preparation of denatured sup(99m)Tc labeled HSA aerosols of different median diameters for various imaging studies

    International Nuclear Information System (INIS)

    Raghunath, B.; Kotrappa, P.; Soni, P.S.; Ganatra, R.D.

    1982-01-01

    The preparation of denatured sup(99m)Tc-labelled human serum albumin (HSA) aerosols of different median diameters is described using the BARC (Bhabha Atomic Research Centre) dry aerosol generation and delivery system. The applications of these radioactive aerosols are demonstrated in aerosol scintigraphy of lungs, mucociliary movement studies and lymphoscintigraphy in rabbits. It is concluded that the BARC system gives a simplified, rapid and versatile procedure for generation of denatured volume tagged HSA aerosols for a variety of clinical applications. (U.K.)

  2. Aerosols behavior inside a PWR during an accident

    International Nuclear Information System (INIS)

    Hervouet, C.

    1983-01-01

    During very hypothetical accidents occurring in a pressurized water ractor, radioactive aerosols can be released, during core-melt, inside the reactor containment building. A good knowledge of their behavior in the humid containment atmosphere (mass concentration and size distribution) is essential in order to evaluate their harmfulness in case of environment contamination and to design possible filtration devices. Accordingly the Safety Analysis Department of the Atomic Energy Commission uses several computer models, describing the particle formation (BOIL/MARCH), then behavior in the primary circuits (TRAP-MELT), and in the reactor containment building (AEROSOLS-PARFDISEKO-III B). On the one hand, these models have been improved, in particular the one related to the aerosol formation (nature and mass of released particles) using recent experimental results. On the other hand, sensitivity analyses have been performed with the AEROSOLS code which emphasize the particle coagulation parameters: agglomerate shape factors and collision efficiency. Finally, the different computer models have been applied to the study of aerosol behavior during a 900 MWe PWR accident: loss-of-coolant-accident (small break with failure of all safety systems) [fr

  3. From the discovery of radioactivity to the production of radioactive beams

    International Nuclear Information System (INIS)

    Bimbot, R.

    1999-01-01

    The evolution of the projectiles used to explore the nucleus influenced strongly the development of Nuclear Physics. The alpha particles from radioactivity were the projectiles mostly used up to the second world war. This period was marked by fundamental discoveries, as those of artificial radioactivity and of fission. From the 1930's to 1070, light accelerated particles (electrons, protons, deuterons, isotopes of helium) became universally used. A third period began in the 1960's with the emergence of heavy ion accelerators, the use of which led to a true revolution in the study of nuclear matter. Finally, the fourth period started in 1985 when the first secondary beams of radioactive nuclei were produced, and opened new ways in physics. (authors)

  4. A new stochastic algorithm for inversion of dust aerosol size distribution

    Science.gov (United States)

    Wang, Li; Li, Feng; Yang, Ma-ying

    2015-08-01

    Dust aerosol size distribution is an important source of information about atmospheric aerosols, and it can be determined from multiwavelength extinction measurements. This paper describes a stochastic inverse technique based on artificial bee colony (ABC) algorithm to invert the dust aerosol size distribution by light extinction method. The direct problems for the size distribution of water drop and dust particle, which are the main elements of atmospheric aerosols, are solved by the Mie theory and the Lambert-Beer Law in multispectral region. And then, the parameters of three widely used functions, i.e. the log normal distribution (L-N), the Junge distribution (J-J), and the normal distribution (N-N), which can provide the most useful representation of aerosol size distributions, are inversed by the ABC algorithm in the dependent model. Numerical results show that the ABC algorithm can be successfully applied to recover the aerosol size distribution with high feasibility and reliability even in the presence of random noise.

  5. Metrological certification of aerosol and iodine channels in instrumentation for radiation monitoring at nuclear power plants

    International Nuclear Information System (INIS)

    Belkina, S.K.; Zalmanzon, Yu.E.; Ivanova, A.P.

    1988-01-01

    The method for converting the value of a volume activity unit of radioactive aerosols using the state special standard for operating measurement devices by means of aerosol sources is suggested. The sources are aerosol samples selected for a filter by means of the proper type of a detection unit or a radiometer and, thus, providing full coincidence of measurement geometry of aerosol sample activity during radiation monitoring. Application of aerosol samples permits to solve the problem of metrological certification and verification of aerosol and iodine channels of radiation safety monitoring systems under operating conditions without their dismantling and to establish the unity and correctness in the field of measurement of volume activity of 131 I aerosols at NPP

  6. Customs control of radioactive materials

    International Nuclear Information System (INIS)

    Causse, B.

    1998-01-01

    Customs officers take part in the combat against illicit traffic od radioactive materials by means of different regulations dealing with nuclear materials, artificial radiation sources or radioactive wastes. The capability of customs officers is frequently incomplete and difficult to apply due to incompatibility of the intervention basis. In case of contaminated materials, it seems that the customs is not authorised directly and can only perform incidental control. In order to fulfil better its mission of fighting against illicit traffic of radioactive materials customs established partnership with CEA which actually includes practical and theoretical training meant to augment the capabilities of customs officers

  7. Dynamics of radioactive lead isotopes in the global environmental atmosphere

    International Nuclear Information System (INIS)

    Koike, Yuya; Kosako, Toshiso

    2006-01-01

    Fundamental information of radioactive lead isotopes, which used as the atmospheric tracer in the global environmental atmosphere, is reviewed. Emanation and exhalation of Rn and Tn, parent nuclide, is stated. Some reports on measurement and application of short-lived lead isotopes are reported. Transfer of radioactive lead isotopes in the atmosphere, vertical profiles of radon, thoron, and short-lived lead isotopes for different turbulent mixing conditions, deposition to aerosol, basic processes of Rn decay product behavior in air defining 'unattached' and 'aerosol-attached' activities, seasonal variation of atmospheric 210 Pb concentration at Beijing and Chengdu, seasonal variation of atmospheric 212 Pb concentration at several observation sites in Japan Islands, and variation in the atmospheric concentration of 212 Pb along with SO 2 are shown. (S.Y.)

  8. Amersham's high radioactivity

    Energy Technology Data Exchange (ETDEWEB)

    Caulkin, S

    1984-11-01

    An account is given of the history, organisation and work of Amersham International, to produce radioactive and other products for use in medical diagnosis and therapy, in research in the life sciences, and in industrial processes and control systems. The account covers the developments from the war-time work of Thorium Ltd., on naturally occurring radioactive materials, through the post-war expansion into the field of artificial radioisotopes, as the Radiochemical Centre (part of the UK Atomic Energy Authority), to the recent reorganisation and privatization. The width of the range of activities and products available is emphasised, with examples.

  9. Amersham's high radioactivity

    International Nuclear Information System (INIS)

    Caulkin, S.

    1984-01-01

    An account is given of the history, organisation and work of Amersham International, to produce radioactive and other products for use in medical diagnosis and therapy, in research in the life sciences, and in industrial processes and control systems. The account covers the developments from the war-time work of Thorium Ltd., on naturally occurring radioactive materials, through the post-war expansion into the field of artificial radioisotopes, as the Radiochemical Centre (part of the UK Atomic Energy Authority), to the recent reorganisation and privatization. The width of the range of activities and products available is emphasised, with examples. (U.K.)

  10. Aerosol and gamma background measurements at Basic Environmental Observatory Moussala

    Directory of Open Access Journals (Sweden)

    Angelov Christo

    2016-03-01

    Full Text Available Trans boundary and local pollution, global climate changes and cosmic rays are the main areas of research performed at the regional Global Atmospheric Watch (GAW station Moussala BEO (2925 m a.s.l., 42°10’45’’ N, 23°35’07’’ E. Real time measurements and observations are performed in the field of atmospheric chemistry and physics. Complex information about the aerosol is obtained by using a threewavelength integrating Nephelometer for measuring the scattering and backscattering coefficients, a continuous light absorption photometer and a scanning mobile particle sizer. The system for measuring radioactivity and heavy metals in aerosols allows us to monitor a large scale radioactive aerosol transport. The measurements of the gamma background and the gamma-rays spectrum in the air near Moussala peak are carried out in real time. The HYSPLIT back trajectory model is used to determine the origin of the data registered. DREAM code calculations [2] are used to forecast the air mass trajectory. The information obtained combined with a full set of corresponding meteorological parameters is transmitted via a high frequency radio telecommunication system to the Internet.

  11. Passive self-cleaning aerosol scrubber

    International Nuclear Information System (INIS)

    Postma, A.K.

    1981-01-01

    A hybrid gas scrubbing system is described, which includes features of both a pool type scrubber and a sand or ground filter, for use on nuclear reactor containment buildings to limit release of aerosol particles and absorbable gases, including radio-active materials, during postulated major accidents. The system requires no energy while in the passive state and no active energy other than pressurization of the stream of gas being scrubbed. (U.K.)

  12. Aerosolization of a Human Norovirus Surrogate, Bacteriophage MS2, during Simulated Vomiting.

    Directory of Open Access Journals (Sweden)

    Grace Tung-Thompson

    Full Text Available Human noroviruses (NoV are the leading cause of acute gastroenteritis worldwide. Epidemiological studies of outbreaks have suggested that vomiting facilitates transmission of human NoV, but there have been no laboratory-based studies characterizing the degree of NoV release during a vomiting event. The purpose of this work was to demonstrate that virus aerosolization occurs in a simulated vomiting event, and to estimate the amount of virus that is released in those aerosols. A simulated vomiting device was constructed at one-quarter scale of the human body following similitude principles. Simulated vomitus matrices at low (6.24 mPa*s and high (177.5 mPa*s viscosities were inoculated with low (108 PFU/mL and high (1010 PFU/mL concentrations of bacteriophage MS2 and placed in the artificial "stomach" of the device, which was then subjected to scaled physiologically relevant pressures associated with vomiting. Bio aerosols were captured using an SKC Biosampler. In low viscosity artificial vomitus, there were notable differences between recovered aerosolized MS2 as a function of pressure (i.e., greater aerosolization with increased pressure, although this was not always statistically significant. This relationship disappeared when using high viscosity simulated vomitus. The amount of MS2 aerosolized as a percent of total virus "vomited" ranged from 7.2 x 10-5 to 2.67 x 10-2 (which corresponded to a range of 36 to 13,350 PFU total. To our knowledge, this is the first study to document and measure aerosolization of a NoV surrogate in a similitude-based physical model. This has implications for better understanding the transmission dynamics of human NoV and for risk modeling purposes, both of which can help in designing effective infection control measures.

  13. A Low Level Radioactivity Monitor for Aqueous Waste

    International Nuclear Information System (INIS)

    Quirk, E.J.M.

    1968-04-01

    A system is described for continuous monitoring of very low levels of radioactivity in waste water containing typically 3.5 g/l dissolved solids. Spray evaporation of the water enables the dissolved solids to be recovered in the form of an aerosol and collected on a filter tape where the radioactivity is measured by a radiation detector. The advantage of this method compared with a direct measurement is that the attenuating effect of the water is removed and thus greater sensitivity is obtained. Compensation for background and any contamination is achieved by feeding distilled water to the aerosol generator every alternate sampling period and recording the count difference between two successive sampling periods . A printed record of the totalised count difference is obtained once per hour during the integration time of one month. For β radioactivity the minimum values of specific activity measurable extend from 1 x 10 -6 Ci/m 3 to 6 x 10 -8 Ci/m depending on the B end-point energy in the range 167 KeV to 2.26 MeV. The estimated minimum measurable specific activity is 6 x 10 -8 Ci/m 3

  14. A Low Level Radioactivity Monitor for Aqueous Waste

    Energy Technology Data Exchange (ETDEWEB)

    Quirk, E J.M.

    1968-04-15

    A system is described for continuous monitoring of very low levels of radioactivity in waste water containing typically 3.5 g/l dissolved solids. Spray evaporation of the water enables the dissolved solids to be recovered in the form of an aerosol and collected on a filter tape where the radioactivity is measured by a radiation detector. The advantage of this method compared with a direct measurement is that the attenuating effect of the water is removed and thus greater sensitivity is obtained. Compensation for background and any contamination is achieved by feeding distilled water to the aerosol generator every alternate sampling period and recording the count difference between two successive sampling periods . A printed record of the totalised count difference is obtained once per hour during the integration time of one month. For {beta} radioactivity the minimum values of specific activity measurable extend from 1 x 10{sup -6} Ci/m{sup 3} to 6 x 10{sup -8} Ci/m depending on the B end-point energy in the range 167 KeV to 2.26 MeV. The estimated minimum measurable specific activity is 6 x 10{sup -8} Ci/m{sup 3}.

  15. Safety of geologic disposal of high level radioactive waste

    International Nuclear Information System (INIS)

    Zaitsu, Tomohisa; Ishiguro, Katsuhiko; Masuda, Sumio

    1992-01-01

    This article introduces current concepts of geologic disposal of high level radioactive waste and its safety. High level radioactive waste is physically stabilized by solidifying it in a glass form. Characteristics of deep geologic layer are presented from the viewpoint of geologic disposal. Reconstruction of multi-barrier system receives much attention to secure the safety of geologic disposal. It is important to research performance assessment of multi-barrier system for preventing dissolution or transfer of radionuclides into the ground water. Physical and chemical modeling for the performance assessment is outlined in the following terms: (1) chemical property of deep ground water, (2) geochemical modeling of artificial barrier spatial water, (3) hydrology of deep ground water, (4) hydrology of the inside of artificial barrier, and (5) modeling of radionuclide transfer from artificial barrier. (N.K.)

  16. Estimating a possibility for automatized monitoring radioactive aerosols in the Ukrytie Object air

    International Nuclear Information System (INIS)

    Zalmanzon, Yu.B.; Fertman, D.E.

    1989-01-01

    The aim of the paper is to study the measurement specifications of the BDAS-OZP industrial detection unit for monitoring aerosols, produced in the Ukrytie object rooms. It is shown that the unit ensures monitoring alpha-active aerosols with radionuclide content of 3x10 -15 Ci/l and beta-active ones - with 3x10 -13 Ci/l. 2 refs.; 1 tabs

  17. Monitoring of radioactivity in the marine environment

    International Nuclear Information System (INIS)

    Bologa, A.S.

    1992-01-01

    The necessity of radioactivity monitoring in the marine environment was imposed by the increasing development of nuclear power and its world-wide use in many different segments of economic and social life. Both natural and artificial radioactivity play an important role in marine ecology and human health. In this respect three major facts continue to prevail in Romania. The fallout, the presence of the Danube river and the expectations for future energy production. Spatial and temporal monitoring of marine radioactivity along the Romanian Black Sea shore has been systematically performed in the Romanian Marine Research Institute in close co-operation with the Institute of Meteorology and Hydrology since 1981. Marine emerged and submerged sediments, coastal and offshore sea water, macroalgae, in vertebrates and fish off the Danube mouths and/or along the coast are monitored for natural and artificial radioactivity by means of beta gross measurements and gamma spectrometry. Concentrations of radionuclides as K-40, Cs-134, Cs-137 in abiotic and biotic samples, environmental distributions coefficients and concentrations factors (CF), as well as experimentally-derived CFs in marine biota as radioecological bioindicators are assessed and stored for a national data base. (author) 3 tabs., 18 refs

  18. Radioactivity monitoring in Ireland of air, deposition and water 1982-1987

    International Nuclear Information System (INIS)

    Sequeira, S.; McRandall, M.; Hayden, E.; Cunningham, J.D.

    1989-02-01

    The Nuclear Energy Board in conjunction with the Meteorological Service undertakes an environmental radioactivity monitoring programme with the objective of determining levels of artificially produced radioactivity in the Irish environment. The levels of radioactivity in airbourne dust, total fallout samples, precipitation and drinking water are presented for 1982, 1983, 1984, 1985, 1986 and 1987

  19. Radioactivity of some dried fruits

    International Nuclear Information System (INIS)

    Akhmedova, G.; Mamatkulov, O.B.; Hushmuradov, Sh.H.

    2004-01-01

    Full text: Radioactivity radiation from natural and artificial sources often acts at the same time in complicated combinations and without exception on all inhabitants of our planet. Natural and artificial radioactive isotopes pass into living organism by biological chain: soil-water-air-plants-foodstuffs-person and can be sources of inside irradiation. Accumulation of radionuclides in living organism in large quantities limit permissible concentration (LPC) can lead to pathological changes in organism. With above mentioned at the radioecological investigations, researches and control of changes of radionuclides concentration in environmental objects have important interests. Investigations of determination of radioactivity of environmental objects, which began in 1960 by professor Muso Muminov are continued in the department of nuclear physics of Samarkand State University. We work out semiconducting gamma-spectrometric method of determination of radionuclides concentration in weak -active environmental samples. We investigated radioactivity of different samples of natural environment and generalized results. In this work the results of investigation of radioactivity of same dried fruits are presented. The spectra of γ-radiation of following dried fruits as grapes, apricot, apple and peach was investigated. In measured gamma-radiation spectra of these samples gamma-transitions of 226 Ra, 232 Th, 40 K natural radionuclides and product of 137 Cs division. The specific gamma-activities these radionuclides were determined. The 40 K have most specific activity and 137 Cs - least. The calculated quantities of specific gamma-activity of radionuclides in gamma-spectra of investigated samples can replace to following row: 40 K > 232 Th > 226 Ra > 137 Cs

  20. Strengths and limitations of the NATALI code for aerosol typing from multiwavelength Raman lidar observations

    Directory of Open Access Journals (Sweden)

    Nicolae Doina

    2018-01-01

    Full Text Available A Python code was developed to automatically retrieve the aerosol type (and its predominant component in the mixture from EARLINET’s 3 backscatter and 2 extinction data. The typing relies on Artificial Neural Networks which are trained to identify the most probable aerosol type from a set of mean-layer intensive optical parameters. This paper presents the use and limitations of the code with respect to the quality of the inputed lidar profiles, as well as with the assumptions made in the aerosol model.

  1. Detection limit improvements forecasted at CTBTO IMS radionuclide stations based on size separation of aerosols by aerodynamic diameter

    International Nuclear Information System (INIS)

    Biegalski, S.; Ezekoye, O.A.; Pena, J.M.; Waye, S.; Pickering, M.

    2008-01-01

    Studies show that aerosols with natural activity have an aerodynamic diameter in the range of 0.1 to 1 μm. In contrast, nuclear explosions generally produce radioactive aerosols with aerodynamic diameters less than 0.1 μm and greater than 1 μm. These differences in aerosol sizes are quite fortuitous because they allow aerosol aerodynamic diameter to be utilized as a physical property to separate aerosols of natural origin from those produced in a nuclear explosion. Data collected in Austin, TX and at U.S. CTBT IMS radionuclide stations have been utilized to forecast detection limit improvements possible given an aerosol size separation capability. (author)

  2. Analysis of the radioactive aerosols sampled with Lepestok respirators during work in the Chernobyl' NPP region

    International Nuclear Information System (INIS)

    Borisova, L.I.; Polevov, V.N.; Borisov, N.B.; Basmanov, P.I.

    1989-01-01

    Aerosols sampled with Lepestok type respirators in the Chernobyl' NPP region following the accident were analysed by gamma-spectroscopic and optical-radiographic methods and nuclide ratio of the aerosol sediment after respirators usage were determined. Parameters of the sampled gamma-active aerosol particles were obtained. ref. 1; tabs. 3

  3. Experimental determination of aerosol deposition velocity on vegetation and on other sampling areas

    International Nuclear Information System (INIS)

    Jonas, R.; Vogt, K.J.

    1982-04-01

    The deposition velocity of aerosols with diameters between 0.4 and 17 μm, required for environmental exposure calculations, was experimentally determined in fifty-two field tests. The results of the deposition experiments on grass indicate that the deposition velocity is proportional to the friction velocity and depends on both the vegetation dry mass and on the aerosol diameter. The deposition velocity can be represented as an inverse polynominal function of the 3rd order as a function of the aerosol diameter. This demonstrated that the deposition velocity increases especially rapidly (by a factor of about 10) between diameters of 4 and 6 μm, for which turbulence deposition is characteristic, while the rise diminishes for larger particles, for which sedimentation is important. It can be assumed that in the normal operation of nuclear power stations and in the case of incidents in which radioactive substances are released in a filtered condition, a particle diameter of 3 μm is not exceeded and differences in friction velocity and dry mass are cancelled out in the temporal mean. At a mean friction velocity of 27 cm/s and a representative dry mass for grass of 0.017 g/cm 2 deposition velocities of 0.01, 0.02, 0.05, 0.42 and 4.6 cm/s resulted, corresponding to particle diameters of 1, 2, 3, 5 and 10 μm. This indicates that the reference value of 0.1 cm/s, given in the 'Allgemeine Berechnungsgrundlage' for the normal operation of nuclear power stations, is sufficiently conservative. The mean deposition velocity for clover was higher by a factor of approximately 2, for artificial interfaces (smooth and structured metals, filters) and soil by a factor of approximately 3 and thus 2 lower than for grass. (orig./HP)

  4. Evidence of the radioactive fallout in France due to the Fukushima nuclear accident

    International Nuclear Information System (INIS)

    Evrard, Olivier; Van Beek, Pieter; Gateuille, David; Pont, Véronique; Lefèvre, Irène; Lansard, Bruno

    2012-01-01

    Radioactive fallout due to the Fukushima reactor explosion in Japan was detected in environmental samples collected in France. The presence of 131 I in aerosols (200 ± 6 μBq m −3 ) collected at the Pic du Midi observatory, located at 2877 m altitude in the French Pyrénées, indicated that the Japanese radioactive cloud reached France between 22 and 29 March, i.e. less than two weeks after the initial emissions, as suggested by a 137 Cs/ 134 Cs ratio of 1.4. Cesium radioisotopes ( 134 Cs and 137 Cs) were not detected in this sample but they were present in the aerosol sample collected the next week, i.e. between 29 March and 05 April (about 10 μBq m −3 ). We also report 131 I activities measured in grass (1.1–11 Bq kg −1 ; fresh weight) and soil samples (0.4 Bq kg −1 ) collected in the Seine River basin between 30 March and 10 April. The 134 Cs from the damaged Fukushima power plant was also detected in grass collected in the Seine River basin between 31 March and 10 April (0.2–1.6 Bq kg −1 fresh weight, with a 137 Cs/ 134 Cs ratio close to 1, which is consistent with Fukushima radioactive release). Despite the installation of a network of nested stations to collect suspended matter in the upstream part of the Seine River basin, 131 I was only detected in suspended matter (4.5–60 Bq kg −1 ) collected at the most upstream stations between 30 March and 12 April. Neither 131 I nor 134 Cs has been detected in environmental samples since the end of April 2011, because of the rapid decay of 131 I and the very low activities of 134 Cs (about 400 times lower than after Chernobyl accident). - Highlights: ► Artificial radionuclides emitted by Fukushima power plant accident were detected in environmental samples collected in France. ► Radioactivity measurements on air filters obtained at the highest altitude in France. ► 131 I detected in grass, soil and sediment collected between 30 March and 12 April. ► 134 Cs detected in grass collected between

  5. Modelling aerosol transfer in a ventilated room

    International Nuclear Information System (INIS)

    Nerisson, Ph.

    2009-02-01

    When particulate radioactive contamination is likely to become airborne in a ventilated room, assessment of aerosol concentration in every point of this room is important, in order to ensure protection of operators and supervision of workspaces. Thus, a model of aerosol transport and deposition has been developed as part of a project started with IRSN, EDF and IMFT. A simplified Eulerian model, called 'diffusion-inertia model' is used for particle transport. It contains a single transport equation of aerosol concentration. The specific study of deposition on walls has permitted to develop a boundary condition approach, which determines precisely the particle flux towards the wall in the boundary layer, for any deposition regime and surface orientation.The final transport and deposition models retained have been implemented in a CFD code called Code-Saturne. These models have been validated according to literature data in simple geometries and tracing experiments in ventilated rooms, which have been carried out in 30 m 3 and 1500 m 3 laboratory rooms. (author)

  6. The penetration of aerosols through fine capillaries

    International Nuclear Information System (INIS)

    Mitchell, J.P.; Edwards, R.T.; Ball, M.H.E.

    1989-10-01

    A novel experimental technique has been developed to study the penetration of aerosol particles ranging from about 1 to 15 μm aerodynamic diameter through capillaries varying from 20 to 80 μm bore and from 10 to 50 mm in length. When the driving pressure was 100 kPa, the penetration of the airborne particles was considerably smaller than expected from a simple comparison of particle diameter with the bore of the capillary. Particle size distributions determined after penetration through the capillaries were in almost all cases similar to the particle size distribution of the aerosol at the capillary entrance. This lack of size-selectivity can be explained in terms of the capillary behaving as a conventional suction-based sampler from a near still (calm) air environment. The resulting particle penetration data are important in assessing the potential for the leakage of aerosols through seals in containers used to transport radioactive materials. (author)

  7. Measurement of radioactivity in steel

    International Nuclear Information System (INIS)

    Wachtendonk, H.-J. von; Luengen, S.; Wilke, N.

    1999-01-01

    Even after the control of scrap deliveries, there remains a small risk that the radioactive contaminated scrap passes the detecting devices. Therefore, the chemical laboratory takes a role to measure each heat for the absence of artificial radioactive nuclides with a gamma spectrometer equipped with NaI-detector. As the measurement must be performed in sequence with the steel production process, the allowable time for the measurement is quite limited. On the other hand, there could be still some possibility that background radiation might be present as the samples may contain some natural radioactivity. The task is how to differentiate the nature of radioactivity between naturally remaining radioactivity within safe limit and artificial nuclides present in the sample at a low level even though a very small amount of radioactivity could be detected in short time in both cases. We have set the alarm limit to 0.1 Bq/g for Co-60 as indicating nuclide. This limit is set more than 4 s (s = standard deviation) from the average background radiation. Therefore, false alarms are quite improbable. Strategy: The NaI gamma spectrometer performs a gross gamma measurement but it can not differentiate the nature of the nuclides present. If the alarm limit is hurt, the sample is measured on a high resolution gamma spectrometer with Ge-detector for identification of the gamma emitting nuclides. Calibration: Even though no appropriate international standards are adapted and no commercial measuring equipment is commercially available, the desired standard should contain Co-60 in the order of 1 to 100 Bq/g. The presence of other gamma emitting nuclides is desirable. In the Workshop we will present how to surmount this difficulty. (author)

  8. Efficiency of the collection of aerosol detectors used in EDF nuclear power stations; Efficacite de collecte des balises aerosol utilisees en CNPE EDF

    Energy Technology Data Exchange (ETDEWEB)

    Fauvel, S.; Gensdarmes, F. [Institut de Radioprotection et de Surete Nucleaire, DSUISERAC, Laboratoire de Physique et de Metrologie des Aerosols, BP 68, 91192 Gif sur Yvette Cedex (France); Valendru, N. [EDF-DPN I UNIE-GPRE, site de CAP Ampere, 93282 Saint Denis Cedex (France)

    2009-07-01

    The authors report an investigation performed to asses the efficiency of different radioactive aerosol detectors by comparing the mass concentration sampled by the tested detectors with the reference mass concentration. The authors describe the measurement installation and protocol, and discuss the results obtained for different grain sizes and different renewal rates

  9. Experimental and numerical study of the degradation of radioactive measurements in the filters of airborne radioactive surveillance systems

    International Nuclear Information System (INIS)

    Geryes, Tony

    2009-01-01

    The measurement of radioactivity in the filters of airborne radioactive surveillance systems is a major metrology difficulty due to the fact that the absorption of a radiation in the filter media and the mass of aerosols accumulated distort the nuclear counting response. This thesis focuses on the determination of correction factors for the radioactivity loss in the survey filters. In a first step, radioactive filters representing the atmospheric samples have been prepared using the nuclear test bench ICARE. The experimental study on reference filters provided a database to determine correction factors for various filtration conditions. The second part proposes a new numerical method developed to determine the correction factors. It consists of coupling GeoDict for particles filtration simulations and MCNPX simulations for a transport in matter. The good agreement obtained by comparing the numerical and experimental correction factors has permitted to validate the numerical model

  10. Radioactive nuclides in the living environment

    International Nuclear Information System (INIS)

    Ueno, Kaoru; Hoshi, Michio.

    1993-09-01

    There are several radioactive nuclides in the living environment, such as those existing since the creation of the earth, those coming from experimental nuclear explosions, and radiations of the cosmic rays. A lesson on these radioactive nuclides was considered useful for understanding the place of nuclear technology, and have been made on the title of 'Radioactive Nuclides in the Living Environment' in the general course of the Nuclear Engineering School of Japan Atomic Energy Research Institute. When the curriculum of the general course was modified in 1993, the lesson was left in a changed form. Thus, the textbook of the lesson is presented in this report. The contents are natural and artificial radioactive nuclides in the living environment and where they have come from etc. (author)

  11. Interference of Heavy Aerosol Loading on the VIIRS Aerosol Optical Depth (AOD Retrieval Algorithm

    Directory of Open Access Journals (Sweden)

    Yang Wang

    2017-04-01

    Full Text Available Aerosol optical depth (AOD has been widely used in climate research, atmospheric environmental observations, and other applications. However, high AOD retrieval remains challenging over heavily polluted regions, such as the North China Plain (NCP. The Visible Infrared Imaging Radiometer Suite (VIIRS, which was designed as a successor to the Moderate Resolution Imaging Spectroradiometer (MODIS, will undertake the aerosol observations mission in the coming years. Using the VIIRS AOD retrieval algorithm as an example, we analyzed the influence of heavy aerosol loading through the 6SV radiative transfer model (RTM with a focus on three aspects: cloud masking, ephemeral water body tests, and data quality estimation. First, certain pixels were mistakenly screened out as clouds and ephemeral water bodies because of heavy aerosols, resulting in the loss of AOD retrievals. Second, the greenness of the surface could not be accurately identified by the top of atmosphere (TOA index, and the quality of the aggregation data may be artificially high. Thus, the AOD retrieval algorithm did not perform satisfactorily, indicated by the low availability of data coverage (at least 37.97% of all data records were missing according to ground-based observations and overestimation of the data quality (high-quality data increased from 63.42% to 80.97% according to radiative simulations. To resolve these problems, the implementation of a spatial variability cloud mask method and surficial index are suggested in order to improve the algorithm.

  12. Reduction of photosynthetically active radiation under extreme stratospheric-aerosol loads

    International Nuclear Information System (INIS)

    Gerstl, S.A.W.; Zardecki, A.

    1981-01-01

    The recently published hypothesis that the Cretaceous-Tertiary extinctions might be caused by an obstruction of sunlight is tested by model calculations. First we compute the total mass of stratospheric aerosols under normal atmospheric conditions for four different (measured) aerosol size distributions and vertical profiles. For comparison, the stratospheric dust masses after four volcanic eruptions are also evaluated. Detailed solar radiative transfer calculations are then performed for artificially increased aerosol amounts until the postulated darkness scenario is obtained. Thus we find that a total stratospheric aerosol mass between 1 and 4 times 10 16 g is sufficient to reduce photosynthesis to 10 3 of normal. We also infer from this result that the impact of a 0.4- to 3-km-diameter asteroid or a close encounter with a Halley-size comet may deposit that amount of particulates into the stratosphere. The darkness scenario of Alvarez et al., is thus shown to be a possible extinction mechanism, even with smaller size asteroids or comets than previously estimated

  13. Reduction of photosynthetically active radiation under extreme stratospheric aerosol loads

    International Nuclear Information System (INIS)

    Gerstl, S.A.W.; Zardecki, A.

    1981-08-01

    The recently published hypothesis that the Cretaceous-Tertiary extinctions might be caused by an obstruction of sunlight is tested by model calculations. First we compute the total mass of stratospheric aerosols under normal atmospheric conditions for four different (measured) aerosol size distributions and vertical profiles. For comparison, the stratospheric dust masses after four volcanic eruptions are also evaluated. Detailed solar radiative transfer calculations are then performed for artificially increased aerosol amounts until the postulated darkness scenario is obtained. Thus we find that a total stratospheric aerosol mass between 1 and 4 times 10 1 g is sufficient to reduce photosynthesis to 10 -3 of normal. We also infer from this result tha the impact of a 0.4- to 3-km-diameter asteroid or a close encounter with a Halley-size comet may deposit that amount of particulates into the stratosphere. The darkness scenario of Alvarez et al. is thus shown to be a possible extinction mechanism, even with smaller size asteroids of comets than previously estimated

  14. Predicting the radioactive contamination of the surroundings near a nuclear power plant

    Energy Technology Data Exchange (ETDEWEB)

    Khristova, M; Paskalev, Z

    1975-01-01

    Predicting the radioactive contamination requires determining the concentration of radioactive material emitted from the stack of a nuclear power plant into the air and deposited on the earth's surface. The main factors determining the degree of contamination are the distance from the stack, the wind velocity and air turbulence. Formulas are presented for predicting the amount of radioactivity as a function of the initial concentration of activity, the distance from the stack and the meteorological condition. Formulas are given for the maximum deposition of radioactive aerosols at a distance R from the stack under wet and dry condtions. 2 refs. (SJR)

  15. Environmental radioactivity and radiation exposure

    International Nuclear Information System (INIS)

    1980-01-01

    In 1977 population exposure in the Federal Republic of Germany has not changed as compared to the previous years. The main share of the total exposure, nearly two thirds, is attributed to natural radioactive substances and cosmic radiation. The largest part (around 85%) of the artificial radiation exposure is caused by X-ray diagnostics. In comparison to this, radiation exposure from application of ionizing radiation in medical therapy, use of radioactive material in research and technology, or from nuclear facilities is small. As in the years before, population exposure caused by nuclear power plants and other nuclear facilities is distinctly less than 1% of the natural radiation exposure. This is also true for the average radiation exposure within a radius of 3 km around nuclear facilities. On the whole, the report makes clear that the total amount of artificial population exposure will substantially decrease only if one succeeds in reducing the high contribution to the radiation exposure caused by medical measures. (orig.) [de

  16. Radiation exposure in an urban dwelling following an accidental release of radioactivity

    International Nuclear Information System (INIS)

    Cannell, Robert J.

    1988-01-01

    The intent of this work is the improved knowledge of how much protection would be afforded to the occupants of a dwelling in the event of a release of radioactivity into the environment. Fundamental to this is the question of how radioactive aerosols and dusts outside of a dwelling affect the inhabitants, what proportion of and by what routes radioactive materials penetrate the structural fabric of the dwelling, and again, how these materials affect the occupants once inside the dwelling. Whilst related research has already provided some answers to this question, experimental work on the tracking of radioactive materials or their analogues was, and still is, required. The major effort of this research has been in the development of an image gathering and processing system which provides a measurement of the mass and spatial distribution of a fluorescent tracer deposited on a surface. Although capable of further refinement, the technique is usable experimentally and its initial use in studying the transport of tracer analogues of radioactive materials is described. One of the main determinants of the behaviour of aerosols is their deposition rate and measurements of this rate for several aerosol-bound radionuclides were made in a test house. The results of these measurements and the dust transport experiments are collated and together with current values from the literature provide the input data for a computer house model. This simple house model has been developed with the primary purpose of indicating which parameters, specifically related to the characteristics of a dwelling, are most influential in determining what degree of protection the occupants will gain. The estimates of protection resulting from the model are summarised, and its sensitivity to the input parameters is used to indicate where further experimental work needs to be undertaken. (author)

  17. Radioactivity in New Zealand meat products

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1986-07-01

    Full text: New Zealand has no nuclear power programme of radioactive waste disposal programme. The only artificial radioactivity detectable in the New Zealand environment is global fallout from nuclear weapons tests conducted mainly in the northern hemisphere before 1964. This fallout in New Zealand is currently at its lowest level since environmental monitoring began in 1960. The total beta activity deposited in rain during 1985, for example, averaged 76 MBQ/km{sup 2}, with most of that being due to naturally occurring radionuclides, principally lead-210/Bismuth-210. Levels of artificial radioactivity in New Zealand dairy products reflect this very low deposition rate. During 1985, for example, Strontium-90 and Caesium-137 levels in cow's milk averaged 0.035 BG/GCA and 0.27BQ/QK respectively. Those levels were similar to, or less than, levels reported in northern hemisphere countries during 1985. No change in environmental contamination levels has been recorded in New Zealand during 1985. The very low deposition rate and milk contamination levels indicate that fallout contamination levels generally are insignificant in New Zealand and monitoring of other foodstuffs such as meat products is not warranted. (author)

  18. Radioactivity in New Zealand meat products

    International Nuclear Information System (INIS)

    1986-01-01

    Full text: New Zealand has no nuclear power programme of radioactive waste disposal programme. The only artificial radioactivity detectable in the New Zealand environment is global fallout from nuclear weapons tests conducted mainly in the northern hemisphere before 1964. This fallout in New Zealand is currently at its lowest level since environmental monitoring began in 1960. The total beta activity deposited in rain during 1985, for example, averaged 76 MBQ/km 2 , with most of that being due to naturally occurring radionuclides, principally lead-210/Bismuth-210. Levels of artificial radioactivity in New Zealand dairy products reflect this very low deposition rate. During 1985, for example, Strontium-90 and Caesium-137 levels in cow's milk averaged 0.035 BG/GCA and 0.27BQ/QK respectively. Those levels were similar to, or less than, levels reported in northern hemisphere countries during 1985. No change in environmental contamination levels has been recorded in New Zealand during 1985. The very low deposition rate and milk contamination levels indicate that fallout contamination levels generally are insignificant in New Zealand and monitoring of other foodstuffs such as meat products is not warranted. (author)

  19. Radioactivity Monitoring of the Irish Environment 2010-2011

    International Nuclear Information System (INIS)

    McGinnity, P.; Currivan, L.; Dowdall, A.; Hanley, O.; Kelleher, K.; McKittrick, L.; Pollard, D.; Somerville, S.; Wong, J.; McMahon, C.

    2012-11-01

    This report presents the results of the environmental radioactivity monitoring programme carried out by the Radiological Protection Institute of Ireland RPII during 2010 and 2011. The RPII has routinely monitored levels of radioactivity in the Irish environment since 1982 and this is the latest in the RPII's series of environmental monitoring reports. The RPII reviews and updates its environmental programme annually to ensure it remains relevant and continues to focus on the most important sources of radioactivity in the environment. The data presented in this report confirm that while the levels of artificial radioactivity in the Irish environment are detectable, they are low. They do not pose a significant risk to the human health of the Irish population. Trace amounts of radioactive isotopes consistent with the Fukushima nuclear accident were detected in air, rainwater and milk samples during the period March to May 2011. These increases in levels of radioactivity were not of concern from a public health point of view. For the remainder of the reporting period, activity concentrations of radionuclides in airborne particles were low and consistent with measurements made in recent years. Radioactivity levels in milk, mixed diet and a wide range of foodstuffs were low and, for the majority of samples, below the detection limits. All drinking waters tested were found to be in compliance with the total indicative dose defined in national and EU legislation. The doses incurred by the Irish public in 2010 and 2011 as a result of artificial radioactivity in the marine environment are small when compared to dose limits or to natural radiation doses received by the Irish public. The doses to the most exposed individuals, members of the oyster and mussel farmers critical group, were approximately 0.02 per cent and 0.05 per cent of the annual dose limit of 1000 microsieverts for members of the public from practices involving controllable sources of radiation in 2010 and

  20. Evaluation of Decontamination Factor of Aerosol in Pool Scrubber according to Bubble Shape and Size

    Energy Technology Data Exchange (ETDEWEB)

    Jo, Hyun Joung; Ha, Kwang Soon; Jang, Dong Soon [KAERI, Daejeon (Korea, Republic of)

    2016-05-15

    The scrubbing pool could play an important role in the wet type FCVS because a large amount of aerosol is captured in the water pool. The pool scrubbing phenomena have been modelled and embedded in several computer codes, such as SPARC (Suppression Pool Aerosol Removal Code), BUSCA (BUbble Scrubbing Algorithm) and SUPRA (Suppression Pool Retention Analysis). These codes aim at simulating the pool scrubbing process and estimating the decontamination factors (DFs) of the radioactive aerosol and iodine gas in the water pool, which is defined as the ratio of initial mass of the specific radioactive material to final massy after passing through the water pool. The pool scrubbing models were reviewed and an aerosol scrubbing code has been prepared to calculate decontamination factor through the pool. The developed code has been verified using the experimental results and parametric studies the decontamination factor according to bubble shape and size. To evaluate the decontamination factor more accurate whole pool scrubber phenomena, the code was improved to consider the variety shape and size of bubbles. The decontamination factor were largely evaluated in ellipsoid bubble rather than in sphere bubble. The pool scrubbing models will be enhanced to apply more various model such as aerosol condensation of hygroscopic. And, it is need to experiment to measure to bubble shape and size distribution in pool to improve bubble model.

  1. Basic approach to the disposal of low level radioactive waste generated from nuclear reactors containing comparatively high radioactivity

    International Nuclear Information System (INIS)

    Moriyama, Yoshinori

    1998-01-01

    Low level radioactive wastes (LLW) generated from nuclear reactors are classified into three categories: LLW containing comparatively high radioactivity; low level radioactive waste; very low level radioactive waste. Spent control rods, part of ion exchange resin and parts of core internals are examples of LLW containing comparatively high radioactivity. The Advisory Committee of Atomic Energy Commission published the report 'Basic Approach to the Disposal of LLW from Nuclear Reactors Containing Comparatively High Radioactivity' in October 1998. The main points of the proposed concept of disposal are as follows: dispose of underground deep enough not be disturb common land use (e.g. 50 to 100 m deep); dispose of underground where radionuclides migrate very slowly; dispose of with artificial engineered barrier which has the same function as the concrete pit; control human activities such as land use of disposal site for a few hundreds years. (author)

  2. Radioactivity and the French uranium bearing minerals

    International Nuclear Information System (INIS)

    Guiollard, P.Ch.; Boisson, J.M.; Leydet, J.C.; Meisser, N.

    1998-01-01

    This special issue of Regne Mineral journal is entirely devoted to the French uranium mining industry. It comprises 4 parts dealing with: the uranium mining industry in France (history, uranium rush, deposits, geologic setting, prosperity and recession, situation in 1998, ore processing); radioactivity and the uranium and its descendants (discovery, first French uranium bearing ores, discovery of radioactivity, radium and other uranium descendants, radium mines, uranium mines, atoms, elements and isotopes, uranium genesis, uranium decay, isotopes in an uranium ore, spontaneous fission, selective migration of radionuclides, radon in mines and houses, radioactivity units, radioprotection standards, new standards and controversies, natural and artificial radioactivity, hazards linked with the handling and collecting of uranium ores, conformability with radioprotection standards, radioactivity of natural uranium minerals); the French uranium bearing minerals (composition, crystal structure, reference, etymology, fluorescence). (J.S.)

  3. Risk assessment for the transportation of radioactive materials in the U.S.A

    International Nuclear Information System (INIS)

    Smith, D.R.; Luna, R.E.; Taylor, J.M.; DuCharme, A.R.

    1976-01-01

    The radiological risk of transporting radioactive materials in the United States was evaluated in terms of expected additional latent cancer fatalities (LCF). Two risks were estimated: that resulting from normal (accident-free) transport and that resulting from transportation accidents involving radioactive shipments. A standard shipments model was devised to represent the radioactive material shipping industry. The calculation of the normal transport risk included estimates of exposures to aircraft passengers and crew, truck drivers, cargo handlers, and population along the transport link. The accident risk calculation incorporated accident probabilities and package release fraction estimates. Dispersible materials were assumed to be aerosolized in severe accidents and the aerosol cloud transported downwind according to a Gaussian diffusion model. An annual normal transport risk of 9600 person-rem, or 1.2 LCF, resulted primarily from radiopharmaceutical shipments. The annual risk due to accidents was 5.6 x 10 -4 LCF, resulting almost entirely from PuO 2 shipments

  4. Survey monitoring of environmental radioactivity in Gunsan area

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Byoung Ho; Ro, Jeong Suk [Kunsan Regional Radioactivity Monitoring Station, Gunsan (Korea, Republic of)

    2001-01-15

    At Regional Radioactivity Monitoring Station in Kunsan have been measured priodically in 2000 gross beta activities in the airborne dust, fallout, precipitation and tap water and gamma exposure rates. Artificial radionuclide of {sup 137}Cs in airborne dust, fallout and precipitation have also been monitored at the station. As a part of environmental radiation/radioactivity distribution survey around Jeon-buk, vegetables, fishes, shellfishes, drinking water (total 33ea) samples were taken from sampling sites which were selected by KINS. We analysis gamma isotope for all. No significant Changes from the previous survey have been found in both beta activities and gamma exposure rates. As the results of analyzig an artificial nuclide concentration in living environmental sample in Jeon-buk are I fee of radiological contaminants.

  5. Survey monitoring of environmental radioactivity in Gunsan area

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Byoung Ho; Ro, Jeong Suk [Kunsan Regional Radioactivity Monitoring Station, Gunsan (Korea, Republic of)

    2002-12-15

    At Regional Radioactivity Monitoring Station in Kunsan have been measured priodically in 2002 gross beta activities in the airborne dust, fallout, precipitation and tap water and gamma exposure rates. Artificial radionuclide of {sup 137}Cs in airborne dust, fallout and precipitation have also been monitored at the station. As a part of environmental radiation/radioactivity distribution survey around Jeon-buk, vegetables, fishes, shellfishes, drinking water (total 33ea) samples were taken from sampling sites which were selected by KINS. We analysis gamma isotope for all. No significant changes from the previous survey have been found in both beta activities and gamma exposure rates. As the results of analyzig an artificial nuclide concentration in living environmental sample in Jeon-buk are fee of radiological contaminants.

  6. Survey monitoring of environmental radioactivity in Gunsan area

    International Nuclear Information System (INIS)

    Kim, Byoung Ho; Ro, Jeong Suk

    2002-12-01

    At Regional Radioactivity Monitoring Station in Kunsan have been measured priodically in 2002 gross beta activities in the airborne dust, fallout, precipitation and tap water and gamma exposure rates. Artificial radionuclide of 137 Cs in airborne dust, fallout and precipitation have also been monitored at the station. As a part of environmental radiation/radioactivity distribution survey around Jeon-buk, vegetables, fishes, shellfishes, drinking water (total 33ea) samples were taken from sampling sites which were selected by KINS. We analysis gamma isotope for all. No significant changes from the previous survey have been found in both beta activities and gamma exposure rates. As the results of analyzig an artificial nuclide concentration in living environmental sample in Jeon-buk are fee of radiological contaminants

  7. Variability of atmospheric depositions of artificial radioelements and their transfer into soils

    International Nuclear Information System (INIS)

    Pourcelot, Laurent

    2008-01-01

    In this Habilitation thesis, I present the results and prospects of the main research topics that contribute to bettering our knowledge of the behaviour of artificial radioelements in the geosphere and biosphere. In the first chapter I present a summary of the research carried out for my thesis on the Oklo reactors. In the subsequent chapters I present my research work at the IRSN. The second chapter concerns the atmospheric depositions of radioactive contaminants. I have studied the principal environmental parameters involved in the empirical modelling of the transfer of artificial radioelements from the atmosphere to the soil. Here I essentially use measurements of artificial radioelements ( 137 Cs, plutonium, americium) in soils that reveal the variability of accidental depositions further to the Chernobyl disaster (paragraph 2.1) and chronic radioactive depositions coming from the atmospheric testing of nuclear weapons (paragraph 2.2). In the third chapter I address the problem of transfers of artificial radioelements into the soil. The interest of this lies in the fact that these transfers represent serious risks for man. Taken over the long term (in the months and years that follow the depositing of radioactive elements on the ground and plants), the transfers of radioactive pollutants into the soil are responsible for the contamination of both plants (transfer via the roots) and underground water and surface water (transfer after vertical migration). My research work into the transfers of radioactive pollutants in soils is centred on vertical migrations and root transfers, as both these processes can be studied through environmental samplings and measurements. More precisely, I have studied the migrations of radioactive pollutants and their geochemical analogues in different types of soils (paragraph 3.1) and the variability of the activities of radiostrontium and radiocesium in the compartments of permanent grassland zones (soil, grass, milk and cheese

  8. The role of chemistry in the history of radioactivity (1897-1939)

    International Nuclear Information System (INIS)

    Adloff, J.P.

    1997-01-01

    Chemical research on radioactivity started in 1898. That year, Pierre and Marie Curie discovered in pitchblende polonium and radium. Rutherford and Soddy showed that radioactivity is an atomic phenomenon accompanied by transmutation of elements and established the basic laws of radioactive changes. The existence of isotopes was postulated after the discovery of many radioactive substances. Major discoveries in nuclear science, i.e. the atomic nucleus, the neutron and artificial radioactivity, were made with radiation sources elaborated bu chemists. Finally, in 1939, radiochemists on the search for transuranium elements, discovered nuclear fission. (authors)

  9. Aerosols generated by 239PU and 233U droplets burning in air

    International Nuclear Information System (INIS)

    Nelson, L.S.; Raabe, O.G.

    1978-01-01

    The inhalation hazards of radioactive aerosols produced by the explosive disruption and subsequent combustion of metallic plutonium in air are not adequately understood. Results of a study to determine whether uranium can be substituted for plutonium in such a situation in which experiments were performed under identical conditions with laser-ignited, single, freely falling droplets of 239 Pu and 233 U are reported. The total amounts of aerosol produced were studied quantitatively as a function of time during the combustion. Also, particle size distributions of selected aerosols were studied with aerodynamic particle separation techniques. Results showed that the ultimate quantity of aerosols, their final particle size distributions, and depositions as a function of time are not identical mainly because of the different vapor pressures of the metals, and the unlike degrees of violence of the explosions of the droplets

  10. Teaching concepts in the field of radioactivity and nuclear energy

    International Nuclear Information System (INIS)

    Bleichroth, W.

    1982-01-01

    This issue of 'Naturwissenschaften im Unterricht', dealing with the subjects of physics and chemistry, gives an account of the fundamentals of radioactivity, nuclear fission, controlled nuclear fission, nuclear power plants, dosimetry, safety engineering, shielding measures to prevent the release of radioactive substances, pressure engineering, emergency core cooling systems, waste disposal and natural and artificial environmental radioactivity. Teachers will find helpful hints as to the method of instruction and the explanation of problems. (DG) [de

  11. Aspects relating to use of radioactively labelled bacteria in animal experiments. 7

    International Nuclear Information System (INIS)

    Heilmann, P.; Flossmann, K.D.; Mueller, G.; Finsterbusch, L.

    1983-01-01

    Two different types of aerosol dispensers were used in an aerosol compartment to apply 59 Fe-labelled bacteria (Pasteurella multocida) to SPE Mini-LEWE piglets as well as to conventionally raised piglets and calves. Germ intake was verified by detection of radioactivity in the lungs. Antigen deposition on each lung amounted to 2-3 . 10 8 in mini-piglets, 6-8 . 10 8 in ordinary piglets, and 2 . 10 9 in conventionally raised calves, as determined by SAG-1, a Soviet model of aerosol dispenser. More or less equally high concentrations of aerosol particles were retained in the pulmonary lobes, independent of the animal species used. Antigen intake could not be influenced by addition of skim milk or by restriction of germ suspensions. (author)

  12. Mechanics of aerosols in nuclear reactor safety: a review

    International Nuclear Information System (INIS)

    Loyalka, S.K.

    1983-01-01

    Although the estimated public risks from nuclear reactors are not high, a significant fraction of these arises from the accident sequences that lead to severe core damage. Calculation of release fractions of the core radioactive inventories for such accidents requires an understanding of the evolution of aerosols in primary coolant systems and reactor containment. The state-of-the-art in the mechanics of a single aerosol particle is reviewed and available work on coagulation of two aerosol particles is discussed. Progress in kinetic theory descriptions and experimental works is described and directions of future work are noted. The General Dynamic Equation for the aerosol distribution is considered, and several forms of this for conditions of interest are noted. Methods of solution that are discussed include analytical techniques, similarity transforms, moments methods and numerical techniques. Computer programs that have been developed in the past few years are also discussed, and their capabilities and limitations are noted. Finally, the comparison of computed results with the available experimental data is discussed, and needs for future research are emphasized. (author)

  13. Ambient radioactivity levels and radiation doses. Annual report 2013; Umweltradioaktivitaet und Strahlenbelastung. Jahresbreicht 2013

    Energy Technology Data Exchange (ETDEWEB)

    Hachenberger, Claudia; Trugenberger-Schnabel, Angela; Loebke-Reinl, Angelika; Peter, Josef (comps.) [Bundesamt fuer Strahlenschutz, Salzgitter (Germany)

    2015-04-15

    The report on environmental radioactivity and radiation exposure 2013 includes data concerning the following issues: sources of natural and artificial radioactivity, radon in buildings, radioactive materials in construction materials and industrial products, nuclear weapon tests, the consequences of reactor accidents in Chernobyl and Fukushima, nuclear facilities, occupational exposure, radiation exposure from medical applications, handling of radioactive materials in research and technology, radioactive wastes, radiation accidents and specific incidents.

  14. Measurement of natural radioactivity and radiation hazards for some natural and artificial building materials available in Romania

    International Nuclear Information System (INIS)

    Muntean, L.E.; Moldovan, D.V.

    2014-01-01

    As building materials are known to be the second source regarding high radon concentrations, it is very important to determine the amounts of natural radionuclides from every building material in use. In the present study the most frequently used Romanian natural (sand, gypsum, limestone) and artificial (portland cement, lime, clinker, electrofilter powder, fly ash, cement-lime plaster mortar, cement plaster mortar) building materials were analyzed. The absorbed dose rate and the annual effective dose equivalent rate for people living in dwelling buildings made of these building materials under investigation were also calculated. The analysis was performed with gamma-ray spectrometry, with two hyper-pure germanium detectors. The activity concentrations of natural radionuclides were in the ranges: 5.2-511.8 Bq kg - 21 for 226 Ra; 0.6-92.6 Bq kg -1 for 232 Th and -1 for 40 K, respectively. The radium equivalent activity in the fifty-one (51) samples varied from 9 to 603 Bq kg -1 . By calculating all the radioactivity indices (R aeq , H ext , I α , I yr ) it was found that all the building materials under investigation can be used to erect dwelling buildings. Except for sample SA6, SA7 and SA11 among the natural building materials and sample SG1, SG2, FAH1, CLM1, CM1 among the artificial building materials that are considered hazardous materials when are used in large quantities. (author)

  15. Fission product and aerosol behaviour within the containment

    International Nuclear Information System (INIS)

    Beard, A.M.; Benson, C.G.; Bowsher, B.R.; Dickinson, S.; Nichols, A.L.

    1990-04-01

    Experimental studies have been undertaken to characterise the behaviour of fission products in the containment of a pressurised water reactor during a severe accident. The following aspects of fission product transport have been studied: (a) aerosol nucleation, (b) vapour transport processes, (c) chemical forms of high-temperature vapours, (d) interaction of fission product vapours with aerosols generated from within the reactor core, (e) resuspension processes, (f) chemistry in the containment. Chemical effects have been shown to be important in defining and quantifying fission product source terms in a wide range of accident sequences. Both the chemical forms of the fission product vapours and their interactions with reactor materials aerosols could have a major effect on the magnitude and physicochemical forms of the radioactive emission from a severe reactor accident. Only the main conclusions are presented in this summary document; detailed technical aspects of the work are described in separate reports listed in the annex

  16. Radioactive contamination of natural and artificial materials

    International Nuclear Information System (INIS)

    Kovalchuk, E.L.; Pomansky, A.A.; Smolnikov, A.A.; Temmoev, A.H.

    1980-01-01

    The gamma radiation of different materials was measured in an underground low-background chamber with extraordinary background characteristics. The excellent background conditions of the measurements enabled investigators to see the alpha-particle peaks of the internal radioactive contamination of NaI(Tl) detectors, which were especially made for these measurements. The sensitivity limit of the installation was determined by the internal contamination of the NaI(Tl) detectors alone. Any radiation background, except for three substances, tungsten, copper, and brass, could be registered

  17. The natural radioactivity of the biosphere

    Energy Technology Data Exchange (ETDEWEB)

    Pertsov, L A

    1967-07-01

    Of the approximately 1200 isotopes presently known more than 900 are radioactive. The nuclei of these isotopes are unstable and decay spontaneously emitting ionizing gamma-, alpha- or beta-radiation. The overwhelming majority of known radioactive isotopes have been obtained artificially; only a few are natural. Numerous investigations have shown that many of the natural radioactive isotopes can be grouped into three radioactive families. Each such family is characterized by the existence of one long-lived isotope - the family parent, one gaseous isotope of radon, intermediate radioactive decay products and final stable isotopes of atomic weights 206, 207 and 208. No such generic relationship has been established among the remaining natural radioactive isotopes. The purpose of the book, in contrast to some recent review works, is to present, in addition to a summary of reference data characterizing the radioactivity levels of various components of the biosphere, a description of those phenomena and regularities which will apparently make it possible to understand more completely the basic dynamics of the natural radioactivity of the biosphere and, consequently, contribute to a more correct interpretation of radiation-hygiene in each specific case.

  18. The natural radioactivity of the biosphere

    International Nuclear Information System (INIS)

    Pertsov, L.A.

    1967-01-01

    Of the approximately 1200 isotopes presently known more than 900 are radioactive. The nuclei of these isotopes are unstable and decay spontaneously emitting ionizing gamma-, alpha- or beta-radiation. The overwhelming majority of known radioactive isotopes have been obtained artificially; only a few are natural. Numerous investigations have shown that many of the natural radioactive isotopes can be grouped into three radioactive families. Each such family is characterized by the existence of one long-lived isotope - the family parent, one gaseous isotope of radon, intermediate radioactive decay products and final stable isotopes of atomic weights 206, 207 and 208. No such generic relationship has been established among the remaining natural radioactive isotopes. The purpose of the book, in contrast to some recent review works, is to present, in addition to a summary of reference data characterizing the radioactivity levels of various components of the biosphere, a description of those phenomena and regularities which will apparently make it possible to understand more completely the basic dynamics of the natural radioactivity of the biosphere and, consequently, contribute to a more correct interpretation of radiation-hygiene in each specific case

  19. Reduction of aerosols produced by ultrasonic scalers.

    Science.gov (United States)

    Harrel, S K; Barnes, J B; Rivera-Hidalgo, F

    1996-01-01

    There is concern with decreased air quality and potential aerosol contamination in the dental operatory. This problem has been addressed by the Centers for Disease Control and Prevention, which recommends that all sources of blood-contaminated splatter and aerosols be minimized. One of the major sources of potential aerosol contamination in the dental setting is the ultrasonic scaler. This study looks at the use of a high volume evacuator attachment for the ultrasonic scaler handpiece. Artificial teeth were mock-scaled for 1 minute with and without the evacuator attachment. The mock scaling was performed within a plastic enclosure that had a 1 cm grid laid out on 4 sides. Scaling was performed 10 times each by 2 operators. An erythrosin solution was used for the ultrasonic scaler coolant with a coolant volume of 17.5 ml/min. The number of squares containing a red erythrosin spot were counted and considered to represent aerosol contamination. The high volume evacuator attachment produced a 93% reduction in the number of contaminated squares (chi squared significant at P < 0.05). There was no increase in heat transfer to a tooth analogue when the high volume evacuator attachment was used with the ultrasonic scaler as compared to the scaler without the evacuator attachment. It is felt that the high volume evacuator attachment is capable of significantly reducing the amount of aerosol contamination produced within the test system without increased heat transfer to the tooth.

  20. Aerosol nucleation induced by a high energy particle beam

    DEFF Research Database (Denmark)

    Enghoff, Martin Andreas Bødker; Pedersen, Jens Olaf Pepke; Uggerhøj, Ulrik I.

    The effect of ions in aerosol nucleation is a subject where much remains to be discovered. That ions can enhance nucleation has been shown by theory, observations, and experiments. However, the exact mechanism still remains to be determined. One question is if the nature of the ionization affects...... the nucleation. This is an essential question since many experiments have been performed using radioactive sources that ionize differently than the cosmic rays which are responsible for the majority of atmospheric ionization. Here we report on an experimental study of sulphuric acid aerosol nucleation under near...... atmospheric conditions using a 580 MeV electron beam to ionize the volume of the reaction chamber. We find a clear and significant contribution from ion induced nucleation and consider this to be an unambiguous observation of the ion-effect on aerosol nucleation using a particle beam under conditions not far...

  1. Nuclear track radiography of 'hot' aerosol particles

    CERN Document Server

    Boulyga, S F; Kievets, M K; Lomonosova, E M; Zhuk, I V; Yaroshevich, O I; Perelygin, V P; Petrova, R I; Brandt, R; Vater, P

    1999-01-01

    Nuclear track radiography was applied to identify aerosol 'hot' particles which contain elements of nuclear fuel and fallout after Chernobyl NPP accident. For the determination of the content of transuranium elements in radioactive aerosols the measurement of the alpha-activity of 'hot' particles by SSNTD was used in this work, as well as radiography of fission fragments formed as a result of the reactions (n,f) and (gamma,f) in the irradiation of aerosol filters by thermal neutrons and high energy gamma quanta. The technique allowed the sizes and alpha-activity of 'hot' particles to be determined without extracting them from the filter, as well as the determination of the uranium content and its enrichment by sup 2 sup 3 sup 5 U, sup 2 sup 3 sup 9 Pu and sup 2 sup 4 sup 1 Pu isotopes. Sensitivity of determination of alpha activity by fission method is 5x10 sup - sup 6 Bq per particle. The software for the system of image analysis was created. It ensured the identification of track clusters on an optical imag...

  2. Nuclear track radiography of 'hot' aerosol particles

    International Nuclear Information System (INIS)

    Boulyga, S.F.; Kievitskaja, A.I.; Kievets, M.K.; Lomonosova, E.M.; Zhuk, I.V.; Yaroshevich, O.I.; Perelygin, V.P.; Petrova, R.; Brandt, R.; Vater, P.

    1999-01-01

    Nuclear track radiography was applied to identify aerosol 'hot' particles which contain elements of nuclear fuel and fallout after Chernobyl NPP accident. For the determination of the content of transuranium elements in radioactive aerosols the measurement of the α-activity of 'hot' particles by SSNTD was used in this work, as well as radiography of fission fragments formed as a result of the reactions (n,f) and (γ,f) in the irradiation of aerosol filters by thermal neutrons and high energy gamma quanta. The technique allowed the sizes and alpha-activity of 'hot' particles to be determined without extracting them from the filter, as well as the determination of the uranium content and its enrichment by 235 U, 239 Pu and 241 Pu isotopes. Sensitivity of determination of alpha activity by fission method is 5x10 -6 Bq per particle. The software for the system of image analysis was created. It ensured the identification of track clusters on an optical image of the SSNTD surface obtained through a video camera and the determination of size and activity of 'hot' particles

  3. Transformation of artificial detritus in lake water

    Energy Technology Data Exchange (ETDEWEB)

    Saunders, G W

    1972-01-01

    It is generally believed that organic detritus constitutes a major fraction of the organic seston in natural waters. Limited data from a productive Michigan Lake indicate that organic detritus ranges from 1.3 to 16.9 times the phytoplankton biomass and usually constitutes more than 50% of the seston (not including zooplankton biomass). Inorganic matter contributes a major portion of the remainer of the seston. Artificial radioactive detritus was generated in samples of surface lake water. The initial net rate of decomposition of this detritus was of the order of 10% per day varying by a factor of two among several experiments. Soluble radioactive carbon derived from artificial detritus amounts to about 1% of the initial radioactivity after one day. This amount of organic carbon could be equal or somewhat greater than that derived from extracellular release by phytoplankton. Radioactive detritus was also fed to natural communities of zooplankton. The results indicate that detritus might be as important as phytoplankton as a food source for daphnia. The relative value of detritus as a food for daphnia appears to shift with change in phytoplankton community structure. A model for carbon flow in the upper photic zone is generated from field experiments. Manipulation of the model indicates that detritus is an energy store that is utilized at relatively slow rates and may function in a buffering capacity to energy flow in the subsystem examined.

  4. Mean residence times of atmospheric aerosols in the boundary layer as determined from 210Bi/210Pb activity ratios

    International Nuclear Information System (INIS)

    Papastefanou, C.; Bondietti, E.A.

    1991-01-01

    Concentrations of radioactive 210 Pb and 210 Bi were measured in surface air after chemical separation and radiochemical analysis in an annual cycle and were used to determine aerosol residence times in the lower atmosphere. It was concluded that residence times of 8 days would apply to aerosols of 0.3 μm activity median aerodynamic diameter (AMAD). Cascade impactor data are also presented in relating the residence times and the AMAD of atmospheric aerosols. (author)

  5. Environmental radioactivity in Hungary

    International Nuclear Information System (INIS)

    Kovacs, J.; Predmerszky, T.

    1979-01-01

    A comprehensive examination of radioactive contamination in air, soil, surface waters and food products, and of natural radioactiviy in air, soil, and building materials has been carried out. The investigated factors were as follows: a) air samples: yearly and monthly beta- and gamma activities of fallout, precipitation and aerosols in the period 1955-1976 in Budapest and some other towns; b) soil samples: 90 Sr concentration of soils of different quality and cultivation originating from sixteen regions of Hungary measured in the period 1974-1976; c) surface waters: annual mean beta activity of five rivers and of the Lake Balaton in the period 1965-1976, 3 H, 137 Cs and 90 Sr activity of the Danube in the year 1976; d) food products: radioactive contamination of spinach, lettuce and oxalis, originating from three different regions in the period 1959-1976 and mean radioactivity of fodder, corn, tobacco, milk, fish and animal bones in a period of 5-10 years; e) natural radioactivity: radon- and toron concentration of air, activity of 226 Ra fallout of the soil in the vicinity of power plants, 226 Ra, 228 Th and 40 K activity of different building materials, radiation doses inside buildings constructed by different technics. (L.E.)

  6. Analysis of the radionuclide ratios in aerosol samples during the Chernobyl accident

    International Nuclear Information System (INIS)

    Sonoc, S.

    2004-01-01

    During the time interval extending from April 29, 1986 to May 12,1986 the National Environmental Radioactivity Surveillance Network has monitored atmospheric aerosol radioactivity by performing six 3 hour samplings a day. The resulting filters were measured beta globally at the stations, then analyzed for gamma emitters at the Environmental Radioactivity Research Laboratory. This paper aims at analyzing the possibilities of identifying the pollutant sources starting from the air concentrations and taking into consideration the influence of the transport upon the contents of the contaminated air masses, by the evaluation of our data and the data in some reports published in other European countries. (author)

  7. Characteristics of the aerosols released to the environment after a severe PWR accident

    International Nuclear Information System (INIS)

    Lhiaubet, G.; Manesse, D.

    1988-05-01

    In the event of a postulated severe accident on a pressurized water reactor (PWR) involving fuel degradation, gases and aerosols containing radioactive products could be released, with short, medium and long term consequences for the population and the environment. Under such accident conditions, the ESCADRE code system, developed at IPSN (Institute for Nuclear Safety and Protection) can be used to calculate the properties of the substances released and, especially with the AEROSOLS/B2 code, the main characteristics of the aerosols (concentration, size distribution, composition). For conditions representative of severe PWR accidents, by varying different main parameters (structural material aerosols, steam condensation in the containment, etc...), indications are given on the range of characteristics of the aerosols (containing notably Cs, Te, Sr, Ru, etc...) released to the atmosphere. Information is also given on how more accurate data (especially on the chemical forms) will be obtainable in the framework of current or planned experimental programs (HEVA, PITEAS, PHEBUS PF, etc...) [fr

  8. Radioactive control of Krsko Nuclear Power Plant in the year 1995

    International Nuclear Information System (INIS)

    Lulic, S.; Miklavzic, U.; Franic, Z.; Kanduc, M.

    1996-01-01

    Regular Krsko Nuclear Power Plant (NPPK) radioactivity control comprises the supervisions of the inventory of liquid and gaseous emissions at the source, and the independent supervisions of the input of radionuclides into larger environment. The controlled environment area consist primarily of a 12 kilometers large circle around the object, where the largest values of immission could be expected, and where possible changes in the Sava river and the underground waters could first be noticed. The circle has been enlarged upon the territory of the Republic of Croatia (RC) from Jesenice on Dolenjsko until Podsused (30 km of air-line distance). As reference points relevant for the readiness in the case of accident, especially for detection of iodine and aerosol air transport, the program comprises also measuring points in the RC at larger distances (from 14 to 27 km) in the direction of Zagreb its larger western surroundings (passive Thermoluminescent (TL) dosimeters in each 42 km long). Continuous of control of emission is performed by the radiological service of (KNPP) by routine procedures, supplemented by adequate measurements from other authorized institutions. Summarized results of radioactive measurements for man-made and natural radionuclides are presented for different transfer media and exposure pathways in the form of assessed effective doses. Conservatively estimated dose burdens received by a member of the reference (critical) population group as the result of NPP emissions amount to a value of the committed effective dose equivalent smaller than 20 μSv/year. This value represents less than 1% of the annual dose received on average from natural and artificial sources by a member of the general public in the normal environment. The yearly doses from natural radioactivity, global contamination , non-nuclear industries and hospitals are also estimated from the measured data in some media. (author)

  9. Atmospheric residence times of continental aerosols

    International Nuclear Information System (INIS)

    Balkanski, Y.J.

    1991-01-01

    The global atmospheric distributions of Rn-222 are simulated with a three-dimensional model of atmospheric transport based on the meteorology of the NASA Goddard Institute for Space Studies (GISS) general circulation model. The short-lived radioactive gas Rn-222 (half-life = 3.8d) is emitted almost exclusively from land, at a relatively uniform rate; hence it is an excellent tracer of continental influences. Lead-210 is produced by decay of Rn-222 and immediately condenses to preexisting aerosol surfaces. It provides an excellent measure of aerosol residence times in the atmosphere because its source is accurately defined by the Rn-222 distribution. Results from the three-dimensional model are compared to measurements of Rn-222 and Pb-210 atmospheric concentrations to evaluate model's long-range transport over oceanic regions and to study the deposition mechanisms of atmospheric aerosols. Model results for Rn-222 are used to examine the long-range transport of continental air over two selected oceanic regions, the subantarctic Indian Ocean and the North Pacific. It is shown that the fast transport of air from southern Africa causes substantial continental pollution at southern mid-latitudes, a region usually regarded as pristine. Air over the North Pacific is heavily impacted by continental influences year round, but the altitude at which the transport occurs varies seasonally. Observations of aerosols at island sites, which are commonly used as diagnostics of continental influences, may be misleading because they do not account for influences at high altitude and because aerosols are efficiently scavenged by deposition during transport. The study of Pb-210 focuses on defining the residence times of submicron aerosols in the troposphere. Scavenging in wet convective updrafts is found to provide the dominant sink on a global scale

  10. Study of air purification in the production of radioactive compounds

    International Nuclear Information System (INIS)

    Fradin, J.; Desroches, J.

    1958-12-01

    As the fabrication of radio-elements takes place in almost airtight enclosures in which a frequent air renewal is required, and while taking the purification rate into account (1.000 to 5.000 m 3 /h), the authors report the study of wet purification in conjunction with dry purification through paper filters, in order to capture dusts. An apparatus has been implemented which allows high gas flow rates. A radioactive aerosol has been introduced in this apparatus and its efficiency has been measured by different means. The authors describe the instrumentation (column, aerosol generator), operation, rate adjustment, and losses. Aerosols of manganese and sodium have been used. Their particle granulometry has been determined. The authors report several types of tests [fr

  11. The puzzle of nuclear wastes. Radioactive threat to your health..

    International Nuclear Information System (INIS)

    2007-01-01

    This document, published by the French association 'Sortir du nucleaire' (Get out of nuclear), gives some information on what is radioactivity, the radioactive materials as a risk for living organisms, nuclear wastes all over France (list and map of the storage sites, power plants and fuel cycle centers), nuclear wastes at every step of the nuclear connection, the insolvable problem of high activity wastes, burying nuclear wastes in order to better forget them, radioactivity as a time bomb for our health, radioactive effluents as an under-estimated risk, artificial radioactivity already responsible for the death of 61 million people in the world, and so on

  12. Radioactivity of household water in Finland

    International Nuclear Information System (INIS)

    Salonen, L.; Saxen, R.

    1991-01-01

    A nationwide study on artificial and natural radioactivity in household water has been under way in Finland since the 1960s. The occurrence of artificial radionuclides in the surface water of drainage basins has been monitored extensively. The proportion of household water derived from surface waters in Finland is currently 48 %, but its usage is decreasing whereas that of groundwater is increasing at an annual rate of 1 - 2 %. The natural radioactivity of household water has been studied in almost all of the waters distributed by public waterworks and in 5400 private ground water wells. The downward trend in 90 Sr, 137 Cs and 3 H concentrations in surface water continued from the middle 1960s until the Chernobyl accident. After the accident ten different radionuclides were detected in surface waters, but only 137 Cs made a minor contribution the radiation dose. The maximum effective dose via ingestion of water was about 0.001 mSv in 1986, and considerably lower in the following years

  13. Transmutation of radioactive wastes: how and why?

    International Nuclear Information System (INIS)

    Patarin, L.

    2004-01-01

    After having evoked the natural or spontaneous transmutation of natural or artificial radioactive atoms, the author describes how this transmutation is technically obtained, indicates the two main families of atoms present in a used nuclear fuel and for which transmutation is to be investigated (long-lived fission residues or products, and transuranium elements) and of which the behaviour in neutron fluxes must be explored. He discusses the industrial means required for artificial transmutation. He discusses the interest of performing such a transmutation

  14. Radioactivity levels in surface water of lakes around Izmir / Turkey

    International Nuclear Information System (INIS)

    Doyurum, S.; Turkozu, D. A.; Aslani, M. A. A.; Aytas, S.; Eral, M.; Kaygun, A. K.

    2006-01-01

    Radioactivity presents in surface continental waters is mainly due to the presence of radioactive elements in the earth's crust, other artificial radionuclides have appeared due to such human activities as nuclear power plants, nuclear weapons testing and manufacture and use of radioactive sources It is well known that natural radionuclides can be effective as tracers for the different processes controlling the distribution of elements among dissolved and particulate phases in aquatic systems. The detection of high radionuclide concentrations was proposed as a public health problem in several areas and consequently studies into the risks of radionuclides were started in the 2000s. Especially, these radioactive substances in groundwater are an unwanted and involuntary risk factor from natural sources, not artificial sources. These radioactive substances include uranium, radon found in uranium series, and other radioactive substances such as radium and gross alpha. Uranium present in rock, soil, and natural materials, and is found in small quantities in air, water, and food that people always contact. In this project, lake water samples were collected from three lakes around Izmir-Turkey. In surface lake water samples, pH, mV and conductivity values were measured and alkaline content was determined titrimetrically. The uranium concentrations in the lake water samples were measured using uranium analyzer. The radioactivity concentrations related to gross radium isotopes, gross-? and gross-? activities in the surface lake water were determined. The correlation among some parameters for water samples and concentrations of uranium, activity concentration of gross radium isotopes, gross alpha and gross beta radioactivity are also discussed

  15. [The distribution of artificial radionuclides in the biomass of macrophytes of the Yenisei River].

    Science.gov (United States)

    Zotina, T A

    2009-01-01

    The Yenisei River is contaminated with artificial radionuclides due to the operation of the Mining-and-Chemical Combine (MCC), Rosatom, producing weapon grade plutonium for several decades. Artificial radionuclides including activation isotopes and transuranics, are detected in the biomass of submerged aquatic plants of the river. We investigated the distribution of artificial radionuclides in the biomass of macrophytes from radioactively contaminated part of the Yenisei River with chemical fractionation techniques. Artificial radionuclides were detected in extracellular and intracellular compartments of the macrophytes. The distribution of radionuclides among the biomass fractions differed essentially. 54Mn was preferably in mobile, exchangeable form compared to other isotopes. Essential portion of 137Cs was in non exchangeable form. Significant activity of artificial radionuclides was detected in the particles of suspended matter of the river, attached to the plant surfaces. Radioactive isotopes were distributed among biomass fractions similar to stable isotopes. The distribution of potassium and 137Cs differed essentially. On the basis of the results obtained the assumptions on the further migration of radionuclides accumulated by aquatic macrophytes in the Yenisei River have been done.

  16. Metrological provision in radiometry of long-lived radionuclide aerosols

    International Nuclear Information System (INIS)

    Belkina, S.K.; Zalmanzon, Yu.E.; Kuznetsov, Yu.V.; Fertman, D.E.

    1984-01-01

    An optimal, as regards expenditures and resulting effect in development, production and operation, scheme is given for metrological provision of working means to measure radioactive aerosols. Model solid sources are recommended to be used for testing calibration and certification of aerosol radiometers when no losses or distortions of information take place. A model radiometer for long-lived radionuclides operating in the 3x10 -2 - 4x10 4 BK/m 3 range of volumetric activity of α-active nuclides and 5-2x10 5 BK/m 3 range of β-active nuclides is successfully utilized at present. Recommendations on reducing the measurement errors by means of different means are given

  17. Metrological provision in radiometry of long-lived radionuclide aerosols

    Energy Technology Data Exchange (ETDEWEB)

    Belkina, S.K.; Zalmanzon, Yu.E.; Kuznetsov, Yu.V.; Fertman, D.E.

    1984-05-01

    An optimal, as regards expenditures and resulting effect in development, production and operation, scheme is given for metrological provision of working means to measure radioactive aerosols. Model solid sources are recommended to be used for testing calibration and certification of aerosol radiometers when no losses or distortions of information take place. A model radiometer for long-lived radionuclides operating in the 3 x 10/sup -2/ - 4 x 10/sup 4/ BK/m/sup 3/ range of volumetric activity of ..cap alpha..-active nuclides and 5-2 x 10/sup 5/ BK/m/sup 3/ range of ..beta..-active nuclides is successfully utilized at present. Recommendations on reducing the measurement errors by means of different means are given.

  18. Survey monitoring of environmental radioactivity in Daejeon area

    Energy Technology Data Exchange (ETDEWEB)

    Jun, Jae Shik.; Noh, Hyung Ah [Taejon Radiation Monitoring Station, Daejeon (Korea, Republic of)

    2000-12-15

    Systematic understanding of the distribution of environmental radioactivity and radiation level in Taejon, including Chungchung area, in normal circumstance, and rapid detection of unusual variation of the radiation level in emergency situation thereby ensure public safety are the objectives of this project to be carried out. This report summarizes and interprets environmental radiation/radioactivity monitoring data obtained at Taejon Radiation Monitoring Station in 2000. In conclusion, the natural environmental radiation level in Taejon area has been preserved as usual and no significant artificial enhancement in environmental radioactivity was observed during the course of this survey and monitoring period.

  19. Survey monitoring of environmental radioactivity in Daejeon area

    Energy Technology Data Exchange (ETDEWEB)

    Jun, Jae Sik; Noh, Hyung Ah [Daejon Radiation Monitoring Station, Daejeon (Korea, Republic of)

    2001-12-15

    Systematic understanding of the distribution of environmental radioactivity and radiation level in Daejeon, including Chungchung area, in normal circumstance, and rapid detection of unusual variation of the radiation level in emergency situation thereby ensure public safety are the objectives of this project to be carried out. This report summarizes and interprets environmental radiation/radioactivity monitoring data obtained at Daejeon Radiation Monitoring Station in 2001. In conclusion, the natural environmental radiation level in Daejeon area has been preserved as usual and no significant artificial enhancement in environmental radioactivity was observed during the course of this survey and monitoring period.

  20. Survey monitoring of environmental radioactivity in Daejeon area

    Energy Technology Data Exchange (ETDEWEB)

    Jun, Jae Shik; Noh, Hyung Ah [Daejon Radiation Monitoring Station, Daejeon (Korea, Republic of)

    2002-12-15

    Systematic understanding of the distribution of environmental radioactivity and radiation level in Daejeon, including Chungchung area, in normal circumstance, and rapid detection of unusual variation of the radiation level in emergency situation thereby ensure public safety are the objectives of this project to be carried out. This report summarizes and interprets environmental radiation/radioactivity monitoring data obtained at Daejeon Radiation Monitoring Station in 2002. In conclusion, the natural environmental radiation level in Daejeon area has been preserved as usual and no significant artificial enhancement in environmental radioactivity was observed during the course of this survey and monitoring period.

  1. Survey monitoring of environmental radioactivity in Daejeon area

    Energy Technology Data Exchange (ETDEWEB)

    Jun, Jae Shik; Noh, Hyung Ah [Daejon Radiation Monitoring Station, Daejeon (Korea, Republic of)

    2003-12-15

    Systematic understanding of the distribution of environmental radioactivity and radiation level in Daejeon, including Chungchung area, in normal circumstance, and rapid detection of unusual variation of the radiation level in emergency situation thereby ensure public safety are the objectives of this project to be carried out. This report summarizes and interprets environmental radiation/radioactivity monitoring data obtained at Daejeon Radiation Monitoring Station in 2002. In conclusion, the natural environmental radiation level in Daejeon area has been preserved as usual and no significant artificial enhancement in environmental radioactivity was observed during the course of this survey and monitoring period.

  2. Survey monitoring of environmental radioactivity in Daejeon area

    International Nuclear Information System (INIS)

    Jun, J. S.; Kim, K. S.

    1998-01-01

    Systematic understanding of the distribution of environmental radioactivity and radiation level in Taejon, including Chungchung area, in normal circumstance, and rapid detection of unusual variation of the radiation level in emergency situation thereby ensure public safety are the objectives of this project to be carried out. This report summarizes and interprets environmental radiation/radioactivity monitoring data obtained at Taejon Radiation Monitoring Station in 1998. In conclusion, the natural environmental radiation level in Taejon area has been preserved as usual and no significant artificial enhancement in environmental radioactivity was observed during the course of this survey and monitoring period

  3. Survey monitoring of environmental radioactivity in Daejeon area

    International Nuclear Information System (INIS)

    Jun, Jae Sik; Noh, Hyung Ah

    2001-12-01

    Systematic understanding of the distribution of environmental radioactivity and radiation level in Daejeon, including Chungchung area, in normal circumstance, and rapid detection of unusual variation of the radiation level in emergency situation thereby ensure public safety are the objectives of this project to be carried out. This report summarizes and interprets environmental radiation/radioactivity monitoring data obtained at Daejeon Radiation Monitoring Station in 2001. In conclusion, the natural environmental radiation level in Daejeon area has been preserved as usual and no significant artificial enhancement in environmental radioactivity was observed during the course of this survey and monitoring period

  4. Radiation safety for incineration of radioactive waste contaminated by cesium

    International Nuclear Information System (INIS)

    Veryuzhs'kij, Yu.V.; Gryin'ko, O.M.; Tokarevs'kij, V.V.

    2016-01-01

    Problems in the treatment of radioactive waste contaminated by cesium nuclides are considered in the paper. Chornobyl experience in the management of contaminated soil and contaminated forests is analyzed in relation to the accident at Fukushima-1. The minimization of release of cesium aerosols into atmosphere is very important. Radiation influence of inhaling atmosphere aerosols polluted by cesium has damage effect for humans. The research focuses on the treatment of forests contaminated by big volumes of cesium. One of the most important technologies is a pyro-gasification incineration with chemical reactions of cesium paying attention to gas purification problems. Requirements for process, physical and chemical properties of treatment of radioactive waste based on the dry pyro-gasification incineration facilities are considered in the paper together with the discussion of details related to incineration facilities. General similarities and discrepancies in the environmental pollution caused by the accidents at Chornobyl NPP and Fukushima-1 NPP in Japan are analyzed

  5. Radioactive particles after different nuclear events in the USSR (overview and modern data)

    Energy Technology Data Exchange (ETDEWEB)

    Gordeev, S.K.; Stukin, E.D.; Kvasnikova, E.V. [Institute of Global Climate and Ecology, Moscow (Russian Federation)

    2004-07-01

    Institute of Global Climate and Ecology participated in all stages of investigations concerning spreading of the radioactive particles formed after nuclear explosions. Since 1963 the radioactive particles from the surface nuclear explosions on the Semipalatinsk Test Site were investigated. Since 1964 the study of the environmental contamination from the underground nuclear explosions (including the cratering nuclear explosions) was carried out. Simultaneously the secondary radioactive aerosols released into the atmosphere from ventilated underground explosions were investigated. Since 1986 the forming and spreading of the radioactive aerosols from Chernobyl accident was studied. An overview of retrospective data will be presented. For example, the fragmentation radionuclides {sup 90}Sr, {sup 137}Cs and {sup 155}Eu, radionuclides induced by neutrons {sup 60}Co, {sup 152}Eu, {sup 154}Eu and transuranium radionuclides {sup 238}Pu, {sup 239+240}Pu and {sup 241}Am were estimated in 15 particles of August, 29, 1949 explosion using the semiconductor spectrometry and radiochemical analysis. Data collection include the samples taken on local traces of ground and underground excavation nuclear explosions, this information will be added by the modern data from soil samples near '1004' explosion (lake Chagan), October 2003. The results of comparison of radionuclide fractionation in the radioactive particles in slag from cratering nuclear explosions and in melt samples will be presented. Main results obtained under the IAEA Research Contract no. 11468. (author)

  6. Roshydromet system of environment radioactive contamination monitoring in the Arctic region of Russia

    International Nuclear Information System (INIS)

    Chelukanov, V.

    1995-01-01

    159 arctic hydrometerological stations take measurements of gamma radiation. 51 stations monitor the density of atmospheric radioactive fallout and 12 stations monitor the concentration of aerosols. 13 hydrological stations sited in the mouths of main Arctic Ocean rivers take water samples. Regional laboratories carry out isotop analysis of samples. Information on high levels of a radioactivity measured at the monitoring stations, as well as information on abnormal radioactivity from regional laboratories are transmitted to the Information Centers on the monitoring system (Moscow and Obnisk) by cable. 2 figs., 1 tab

  7. Pyrotechnical production of labelled aerosols and their use in the ground atmosphere

    International Nuclear Information System (INIS)

    Kuehn, W.K.G.; Alps, W.

    1977-01-01

    As the emission of radioactive substances in the atmosphere is only allowed for a few short-lined radionuclides, the possibility of producing aerosols pyrotechnically and to simultaneously label them with easily activated tracers was investigated. It has the following advantages: 1) The activation analysis guarantees a high detection sensitivity with a tracer element of large cross section. 2) There is no danger to the environment due to radioactivity during testing. 3) In general, there are no limits to the amount of indicator substance used. 4) The pyrotechnically produced aerosol can be used at any position of the atmosphere whereby line sources, point sources and pulse sources can be produced with the generator. The generator can be shot by a signal pistol to the desired height in order to label harmful substances or other (emission) points as well. 5) The source is extremely mobile due to the small measurements and uncomplicated construction of the generator. (orig./RW) [de

  8. The system for measurements of radioactive contamination of environment and food in Poland

    International Nuclear Information System (INIS)

    Grabowski, D.; Kurowski, W.

    1990-01-01

    The service for Measurements of Radioactive Contamination comprises a network of 152 measuring stations. They are carrying out continuous measurements of gamma radiation dose rates and radioactivity measurements of 24 hours samples of air (aerosols) and total fallout. On the territory of each province there are selected points for sampling of environmental materials and food. Frequency of sampling depends on material being collected. 1 tab., 2 figs. (A.S.)

  9. Nuclear Aerosols: Direct Simulation and Elucidation of the Role of Multiple Components, Radioactivity, Charge, Shape and Spatial Inhomogeneity

    International Nuclear Information System (INIS)

    Sudarshan K. Loyalka

    2008-01-01

    Nuclear aerosols can originate from severe core damage in light water reactors, core disruptive accidents in fast reactors, nuclear accidents during nuclear material transport, at waste disposal sites, or explosions. These aerosols evolve under natural transport processes as well as under the influence of engineered safety features. Such aerosols can be hazardous for the equipment inside the reactor, and when leaked into the environment, pose potential risks to the public. Hence, the origin, movement and distribution of these aerosols need to be studied and controlled

  10. Demister apparatus for gaseous wastes carrying radioactive aerosols

    International Nuclear Information System (INIS)

    Meline, F.G.; Richter, R.J.

    1983-01-01

    In the nuclear industry, more precisely in the field of spent fuel reprocessing, the cleaning of the gaseous wastes, before evacuation, should be realized with a device designed in order to take full account of the constraints that are inherent in the radioactive media. The French Atomic Authority (CEA), in collaboration with the Societe Generale pour les Techniques Nouvelles, have studied and developed types of demister for the nuclear field having good cleaning properties

  11. Radioecological aspects in artificial groundwater recharge

    Energy Technology Data Exchange (ETDEWEB)

    Matthess, G [Kiel Univ. (Germany, F.R.). Geologisch-Palaeontologisches Inst. und Museum; Neumayr, V [Institut fuer Wasser-, Boden- und Lufthygiene, Frankfurt am Main (Germany, F.R.)

    1980-01-01

    In increasing extent surface waters, especially those of rivers and streams, are contaminated by radionuclides. Therefore it is necessary to investigate the possibility of impairment of the quality of artificially recharged groundwater and drinking water by radionuclides. Hazards for man are possible by drinking water, that was affected by waste and during exposition to air, as well as indirectly by irrigation water and the food chain. In a model calculation using realistic conditions the order of magnitude of these hazards for man by incorporation of radioactively contaminated artificially recharged drinking water are to be assessed. Here the parameters are discussed which must be considered in such an assessment. The model includes the use of river water for artificial recharge. All models and assessments assume the most unfavourable preconditions, which may lead to an impact to man.

  12. Atmospheric washout of radioactive aerosol for different types of precipitation events

    International Nuclear Information System (INIS)

    Bernauer, Felix

    2015-01-01

    Ionizing radiation is widely used in many applications such as medical diagnostics and radiotherapy, where the beneficial aspect of radiation exposure is obvious. However, the exposure of human beings to ionizing radiation may also have some negative effects on human health. After the Fukushima Dai-Ichi nuclear power plant accident measured deposition patterns did not match to patterns predicted by atmospheric transport models used in decision support systems. It was suggested that one reason for these discrepancies might be that these models do not differentiate between deposition by rain and snow. Up to now much effort has been spent on the theoretical and experimental investigation of the washout of atmospheric aerosol particles by rain. In contrast, only limited knowledge is available on the washout efficiency of snow, due to the complexity of the process. Therefore, the aim of the presented work was to analyze wet deposition of aerosol particles and particle bound radionuclides in different types of precipitation events. The thesis focused on below-cloud scavenging of aerosol particles in a size range from 10 nm to 510 nm in solid phase precipitation events. It is based on measurements of natural precipitation and natural aerosol particle concentration that were performed in the free atmosphere, at the Environmental Research Station Schneefernerhaus. For this purpose, a method was developed to characterize and classify precipitation events, which goes beyond the common differentiation between liquid, mixed and solid phase precipitation. The method included use of a 2D-Video Disdrometer (2DVD), that was adapted for the detection of mixed and solid phase hydrometeors (e.g. snowflakes). A new matching algorithm, that was developed for this thesis, allowed detection of solid, mixed and liquid phase hydrometeors with a maximum dimension larger than 0.5 mm. On the basis of shape and velocity descriptors, a classification algorithm that differentiates between three

  13. Atmospheric washout of radioactive aerosol for different types of precipitation events

    Energy Technology Data Exchange (ETDEWEB)

    Bernauer, Felix

    2015-12-15

    Ionizing radiation is widely used in many applications such as medical diagnostics and radiotherapy, where the beneficial aspect of radiation exposure is obvious. However, the exposure of human beings to ionizing radiation may also have some negative effects on human health. After the Fukushima Dai-Ichi nuclear power plant accident measured deposition patterns did not match to patterns predicted by atmospheric transport models used in decision support systems. It was suggested that one reason for these discrepancies might be that these models do not differentiate between deposition by rain and snow. Up to now much effort has been spent on the theoretical and experimental investigation of the washout of atmospheric aerosol particles by rain. In contrast, only limited knowledge is available on the washout efficiency of snow, due to the complexity of the process. Therefore, the aim of the presented work was to analyze wet deposition of aerosol particles and particle bound radionuclides in different types of precipitation events. The thesis focused on below-cloud scavenging of aerosol particles in a size range from 10 nm to 510 nm in solid phase precipitation events. It is based on measurements of natural precipitation and natural aerosol particle concentration that were performed in the free atmosphere, at the Environmental Research Station Schneefernerhaus. For this purpose, a method was developed to characterize and classify precipitation events, which goes beyond the common differentiation between liquid, mixed and solid phase precipitation. The method included use of a 2D-Video Disdrometer (2DVD), that was adapted for the detection of mixed and solid phase hydrometeors (e.g. snowflakes). A new matching algorithm, that was developed for this thesis, allowed detection of solid, mixed and liquid phase hydrometeors with a maximum dimension larger than 0.5 mm. On the basis of shape and velocity descriptors, a classification algorithm that differentiates between three

  14. Aerosol behaviour calculations with the code NAUA-Mod5M

    International Nuclear Information System (INIS)

    Bunz, H.; Koyro, M.

    1995-03-01

    This report presents the aerosol behaviour calculations within the framework of SEAFP task A8 'Radioactivity confinement analysis'. The retention capability for the aerosol-type activity of the containment has been evaluated for a number of different accident scenarios with the code NAUA-Mod5M. This code is designed to simulate the aerosol behaviour for an arbitrary multi-compartment containment originally for applications in LWR containments after severe accidents. Altogether six different scenarios have been evaluated, two for the He-cooled RPM and four for the watercooled APM. These scenarios differ mainly in the primary source taken into account, if e.g. the armour of the first wall consists of Be or W or if the divertor cooling loop or a primary cooling loop fails. The results show the positive influence of the system of step by step barriers already proved to be successful for other applications. (orig.) [de

  15. Radioactive Control of Krsko Nuclear Power Plant Environment in the Year 1997

    International Nuclear Information System (INIS)

    Lulic, S.; Miklavzic, U.; Franic, Z.; Kanduc, M.

    1998-01-01

    Regular Krsko Nuclear Power Plant (NPPK) radioactivity control comprises the supervisions of the inventory of liquid and gaseous emissions at the source, and the independent supervisions of the input of radionuclides into larger environment (imisson). The controlled environment area consists primarily of a 12 kilometers large circle around the object, where the largest values of imission could be expected, and where possible changes in the Sava river and the underground waters could first be noticed. The circle has been enlarged upon the territory of the Republic of Croatia (RC) from Jesenice on Dolenjsko until Podsused (30 km of air - line distance). As reference points relevant for the readiness in the case of accident, especially for detection of iodine and aerosol air transport, the program comprises also measuring points in the RC at larger distances (from 14 to 27 km) in the direction of Zagreb its larger western surroundings (passive Thermoluminescent (TL) dosimeters in the each 42 km long). Continuous control of emission is performed by the radiological service of KNPP by routine procedures, supplemented by adequate measurements from other authorized institutions (intercomparisons, parallel measurements of representative and other samples). Summarised results of radioactive measurements for man-made and natural radionuclides are presented for different transfer media and exposure pathways in the form of assessed effective doses. Conservatively estimated dose burdens received by a member of the reference (critical) population group as the result of NPP emissions amount to a value of the committed effective dose equivalent smaller than 20 μSv/year. This value represents less than 1 % of the annual dose received on average from natural and artificial sources by a member of the general public in the normal environment. The yearly doses from natural radioactivity, global contamination (Chernobyl, atmospheric nuclear explosions), non-nuclear industries and

  16. An Assessment of Radioactivity of Selected Industrial Waste

    International Nuclear Information System (INIS)

    Huwait, M. A.; ElMongy, S.A.; Abdo, A.A.A.; Hassan, M.H.

    1999-01-01

    phosphogypsum (phph) is a by-product in the manufacture of phosphoric acid for the artificial fertilizer industry. In the present work, qualitative and quantitative radioactive analysis are carried for phph of National Company of Abuzabal for chemical fertilizers. Gamma ray spectroscopy techniques are applied. The present study reveals that the radioactivity resulted from these wastes is out of the international standards, and it is strongly not recommended to be used as a construction material or for dwellings

  17. Valuating report on radionuclide concentrations in aerosols in 1988

    International Nuclear Information System (INIS)

    Henrich, E.; Friedrich, M.; Haider, W.

    1989-03-01

    Sample preparation - and measuring methods and results on aerosol samples from the Austrian Environment Radioactivity Monitoring Network are presented. Special emphasis is on Cs-134, Cs-137 (Chernobyl fallout) and I-131 from medical applications. Comparisons with 1987 are made. The lung doses for the population are estimated to be 0,5 - 5 nSv, i.e. very small. 8 refs., 15 figs., 11 tabs. (qui)

  18. Determining the effect of turbulent shear on containment aerosol dynamics using microgravity experiments

    International Nuclear Information System (INIS)

    Scott, C.K.; Abdelbaky, M.

    1997-01-01

    Determining the characteristics of large aerosol aggregates 'clusters' under turbulent conditions is fundamental for predicting the behaviour of radioactive aerosols inside the reactor containment following a severe accident. Studying such rapidly settling clusters is extremely difficult in ground-based experiments due to the effect of the earth's gravity. In this study, the microgravity environment is exploited to investigate the effect of turbulent shear on the aggregation and breakage of clusters by examining their structure and measuring their strength parameters while suspended under weightlessness conditions. A parametric model is introduced to correlate the experimental results over into nuclear aerosol models. It was demonstrated that the cluster parameters depend mainly on the turbulent field intensity as well as initial powder conditions. (author)

  19. Sensitivity of depositions to the size and hygroscopicity of Cs-bearing aerosols released by the Fukushima Nuclear Accident

    Energy Technology Data Exchange (ETDEWEB)

    Kajino, Mizuo [Meteorological Research Institute, 1-1 Nagamine, Tsukuba, Ibaraki 305-0052 (Japan); RIKEN Advanced Institute for Computational Science, 7-1-26 Minatojima-minamimachi, Chuo-ku, Kobe, Hyogo 650-0047 (Japan); Adachi, Kouji; Sekiyama, Tsuyoshi T.; Zaizen, Yuji; Igarashi, Yasuhito [Meteorological Research Institute, 1-1 Nagamine, Tsukuba, Ibaraki 305-0052 (Japan)

    2014-07-01

    We recently revealed that the micro-physical properties of aerosols carrying the radioactive Cs released from the Fukushima Daiichi Nuclear Power Plant (FDNPP) at an early stage (March 14-15, 2011) of the accident could be very different from what we assumed previously: super-micron and non-hygroscopic at the early stage, whereas sub-micron and hygroscopic afterwards (at least later than March 20-22). In the study, two sensitivity simulations with the two different aerosol micro-physical properties were conducted using a regional scale meteorology- chemical transport model (NHM-Chem). The impact of the difference was quite significant. 17% (10-3%) of the radioactive Cs fell onto the ground by dry (wet) deposition processes, and the rest was deposited into the ocean or was transported out of the model domain, which is central and northern part of the main land of Japan under the assumption that Cs-bearing aerosols are non-hygroscopic and super-micron. On the other hand, 5.7% (11.3%) fell onto the ground by dry (wet) deposition, for the cases under the assumption that the Cs-bearing aerosols are hygroscopic and sub-micron. For the accurate simulation of the deposition of radionuclides, knowledge of the aerosol micro-physical properties is essential as well as the accuracy of the simulated wind fields and precipitation patterns. (authors)

  20. AKTIS Nr. 12: To better understand radioactive aerosol deposit in order to better measure it; Radio-induced lesions: a new step towards healing; Modelling the collapse of an immersed grain column; To better model soot deposit; Towards the prediction of the leakage rate of containment enclosures

    International Nuclear Information System (INIS)

    Benderitter, Marc; Perales, Frederic; Monerie, Yann; Maro, Denis; Boyer, Patrick; Lemaitre, Pascal; Porcheron, Emmanuel; Depuydt, Guillaume; Masson, Olivier; Gensdarmes, Francois

    2013-04-01

    This publication presents the main results of researches undertaken by the IRSN in the field of radiation protection, nuclear safety and security. The topics herein addressed are: radio-induced lesions as a new step towards healing (case of injection mesenchymal stem cells for the treatment of induced severe colorectal lesions), the modelling of the collapse of an immersed grain column (to study the nuclear fuel behaviour in an accidental situation through a modelling of fluid-grain interactions), a better understanding of radioactive aerosol deposit (to study particle or aerosol deposits after radioactive releases in the atmosphere in case of accident), a better modelling of soot deposits (in case of fire), the prediction of leakage rates of containment enclosures (ageing phenomena of installations, systems and equipment, with the case of cracks due to material ageing and resulting in confinement losses which could thus be quantified)

  1. Bio indicator organisms available to use for determination of radioactive elements in Turkey's seas

    International Nuclear Information System (INIS)

    Kocbas, F.; Guener, H.

    2006-01-01

    In determination of radioactive concentration and monitoring alive and lifeless environmental samples possess a significant place. Thus, intense study is carried out related to natural and artificial radionuclides sediment. Bio indicator living organisms inhabiting in sea ecosystems; are being evaluated in researches such as determinations of environmental pollution, natural and artificial radioactive elements. Turkey's seas are rich related to diversification of various types. In determining and monitoring radioactivity concentration widespread implementation of some sorts appeal attention and on the other hand inadequate usage of many types is observed. In the present study, providing information about the bio indicator organisms keep living in seas and plays important role in food supply chain and increasing the numbers of the types of organisms used are aimed

  2. Human Health Impact of Natural and Artificial Radioactivity Levels in the Sediments and Fish of Bonny Estuary, Niger Delta, Nigeria

    Directory of Open Access Journals (Sweden)

    Bolaji B. Babatunde

    2015-11-01

    Full Text Available There is widespread contamination of the environment of the Niger Delta, which may include enhanced background levels of naturally occurring radioactive materials (NORM due to oil production and rapid urbanization activities. Sediments and seafood from the Bonny estuary, Niger Delta, were collected for the purpose of determining baseline data on artificial and natural radioactivity and estimation of effective doses for the public due to ingestion of seafood from the study area. The highest and lowest activity concentrations were reported for 40K and 137Cs in both sediments and fish samples of the Bonny estuary. There was some evidence of spatial variability in the 40K and 137Cs data, with the latter being the likely result of dredging. Other radionuclides were not significantly different between sites impacted by industrial activities or not. Activity of radionuclides measured in the sediments of the study area were higher than reported elsewhere in the Niger Delta and Nigeria and higher than reported global averages by UNSCEAR. The total highest activity concentration in all fish species of gamma emitting radionuclides was observed for 40K, followed by 238U, 232Th and 226Ra, respectively, while 137Cs had the lowest activity concentration. However, 210Po activities were the most important in terms of dose contribution. Consumption of molluscs at typical rates could result in doses exceeding 1 mSv·y−1. Although this baseline data may not be conclusive on prevailing trends in radioactivity in the study area, higher consumption rates of the species studied may have public health consequences due to effects of low dose ionising radiation.

  3. Atmospheric Residence Times of Continental Aerosols.

    Science.gov (United States)

    Balkanski, Yves Jacques

    The global atmospheric distributions of ^{222}Rn and ^{210 }Pb are simulated with a three-dimensional model of atmospheric transport based on the meteorology of the NASA GISS^1>=neral circulation model. The short-lived radioactive gas ^ {222}Rn (half-life = 3.8d) is emitted almost exclusively from land, at a relatively uniform rate; hence it is an excellent tracer of continental influences. Lead -210 is produced by decay of ^{222} Rn and immediately condenses to preexisting aerosol surfaces. It provides an excellent measure of aerosol residence times in the atmosphere because its source is accurately defined by the ^{222} Rn distribution. Results from the three-dimensional model are compared to measurements of ^ {222}Rn and ^{210 }Pb atmospheric concentrations to evaluate model's long-range transport over oceanic regions and to study the deposition mechanisms of atmospheric aerosols. Model results for ^{222} Rn are used to examine the long-range transport of continental air over two selected oceanic regions, the subantartic Indian Ocean and the North Pacific. It is shown that fast transport of air from southern Africa causes substantial continental pollution at southern mid-latitudes, a region usually regarded as pristine. Air over the North Pacific is heavily impacted by continental influences year round, but the altitude at which the transport occurs varies seasonally. Observations of aerosols at island sites, which are commonly used as diagnostics of continental influences, may be misleading because they do not account for influences at high altitude and because aerosols are efficiently scavenged by deposition during transport. The study of ^{210}Pb focuses on defining the residence times of submicron aerosols in the troposphere. Scavenging in wet convective updrafts is found to provide the dominant sink on a global scale. The globally averaged residence time for ^{210 }Pb-containing aerosols in the troposphere is 7 days. The average increase in residence time

  4. Behavior of generated aerosols in decommissioning of reactor

    International Nuclear Information System (INIS)

    Tomii, H.; Nakamura, K.

    1999-01-01

    Generated aerosols in dismantling of the JPDR were investigated for making an estimation of air contamination. The maximum dose equivalent rate at the surface of each reactor component was 9.4 Sv/h for core shroud, 80 mSv/h for pressure vessel, 2.0 mSv/h for biological shield, respectively. An under-water cutting method with remote handling plasma torch was used for dismantling of the core shroud and the pressure vessel. The biological shield was dismantled by an in-air cutting method and a controlled blasting method. Pipes connected to recirculation system were dismounted by a conventional mechanical and thermal cutting machine in the air. Generated radioactive aerosols were collected in the exhaust air of green house which enclosed the upper part of the reactor room to control the air contamination. An Andersen sampler was used for the measurement of particle distribution in the aerosols. Most of the particle size was below 0.1 μm in the under-water cutting method. The particle size distribution in the in-air cutting method, however, was divided into two parts at 0.1 μm and 0.3 μm. Dispersion rate of aerosol into the atmosphere was decreased exponentially with the depth of water. The dispersion rate and the size distribution of aerosol generated during cutting of the stainless steel pipes and blasting of the biological shield are also reported in the paper. (Suetake, M.)

  5. Distribution of radioactive constituents in river waters

    International Nuclear Information System (INIS)

    Herranz, M.; Elejalde, C.; Legarda, F.; Romero, F.

    1994-01-01

    For a research project on the distribution and evaluation of natural and artificial radioactive constituents in ecological segments of Biscay (northeast spain), the amounts of nuclides present in the main river waters were measured. Radioactive procedures include i) total alpha and beta indexes with a gas flow detector, dry residues near to 2 and 10 mg/ cm sup 2, respectively and counting periods of 1000 mn, ii) gamma emitters with a low level gamma spectrometer (Ge-HP detector + 8000 channels analyser) using the dry residue from 8 litres and a counting period of 4 days and iii) statistical treatment of data at 95% confidence.In this paper, ten water samples from the nervion river basin are included. Physical and chemical parameters of samples were also determined by standard procedures, because there is a sharp change in the composition of this river in the first part of the course. Radioactive constituents were identified as follows: a sample has a detectable alpha index, all samples contains beta emitters with a high variability, natural nuclides from uranium and thorium families were detected in some cases. A parallel behaviour is found between samples where K-40 and Cs-137 were found. The paper tries at last to find relations among chemical and radioactive constituents by the application of multivariate statistical methods, specially for the case of Cs-137, the only artificial nuclide identified in this work. 1 tab., 2 figs., 5 refs. (author)

  6. Decontamination by foams: A promising treatment for the removal of radioactive dust from gas streams

    International Nuclear Information System (INIS)

    Mitchell, J.P.

    1989-06-01

    Foams provide a promising method for the treatment of gas streams containing radioactive aerosol particles. A review of the literature has been undertaken to define and assess the mechanics of aerosol behaviour in contact with foams. Applications are also examined in which foams have been used to treat aerosols. Key issues are identified which require further study. In particular, the efficiency of sub-micron particle removal can be determined using recently developed analysers and the use of the process gas to generate the foam could have a major impact on the design of commercial units. (author)

  7. The influence of salt aerosol on alpha radiation detection by WIPP continuous air monitors

    Energy Technology Data Exchange (ETDEWEB)

    Bartlett, W.T.; Walker, B.A. [Environmental Evaluation Group, Albuquerque, NM (United States)

    1997-08-01

    Waste Isolation Pilot Plant (WIPP) alpha continuous air monitor (CAM) performance was evaluated to determine if CAMs could detect accidental releases of transuranic radioactivity from the underground repository. Anomalous alpha spectra and poor background subtraction were observed and attributed to salt deposits on the CAM sampling filters. Microscopic examination of salt laden sampling filters revealed that aerosol particles were forming dendritic structures on the surface of the sampling filters. Alpha CAM detection efficiency decreased exponentially as salt deposits increased on the sampling filters, suggesting that sampling-filter salt was performing like a fibrous filter rather than a membrane filter. Aerosol particles appeared to penetrate the sampling-filter salt deposits and alpha particle energy was reduced. These findings indicate that alpha CAMs may not be able to detect acute releases of radioactivity, and consequently CAMs are not used as part of the WIPP dynamic confinement system. 12 refs., 12 figs., 1 tab.

  8. Surveillance of the radioactivity in the environment of the Loire basin

    International Nuclear Information System (INIS)

    2008-12-01

    The surveillance of the radioactivity in environment in the Loire catchment basin rests on the measurement of radioactivity in atmosphere, in the rain waters and continental waters as well as the follow up of radioactivity in food chain. Concerning the air radiation monitoring, that is the dose rate measurement of ambient gamma radiation, the radon measurement and the measurement of particulates and radioactive aerosols. Concerning the food chain, the follow up is made on drinking water, milk, fishes and the special case of strontium 90. The actors of this campaign are the institute of radiation protection and nuclear safety (I.R.S.N.), Electricite de France (E.D.F.) Areva NC, the associations qualified for the surveillance of air quality (A.A.S.Q.A.) and the government services. (N.C.)

  9. Radioactivity and Environment. Radioactividad y Medio Ambiente

    Energy Technology Data Exchange (ETDEWEB)

    Sanchez Leon, J.G. (Jefe de Seguridad Nuclear de la Fabrica de Juzbado. Empresa Nacional de Uranio. (Spain))

    1993-01-01

    Radioactivity is one of the most studied natural phenomena. Most of irradiation suffered by the human being is produced by natural sources. The second source in order of importance is nuclear medicine. The average level of radiation received by the man is 2.4 mSv/year and this value can be modified naturally in 20-30%. The author provides a review on radioactivity sources like natural (cosmic rays, extraterrestrial radiation, internal earth radiation, radon) and artificial (Nuclear explosions, professional exposure, nuclear medicine, nuclear power plants and accidents).

  10. Study of the attachment between the decay products of 220Rn and monodisperse aerosols

    International Nuclear Information System (INIS)

    Kruger, J.

    1974-10-01

    Attachment can be described in terms of one of two theories, viz. the diffusion theory or the kinetic theory. The diffusion theory is based on the transport of radioactive atoms by means of the process of diffusion. An attachment proportional to the radius R of the aerosol particles for the size range used in these experiments, is predicted by this theory. The kinetic theory is based on intermolecular collisions as described by the kinetic theory of gasses. This theory predicts an attachment that is proportional to R 2 . Both these relationships have been established by other researchers. However, the author believes that they have not taken several important parameters into consideration in their experiments, several such parameters were also not properly controlled in their experiments. In the present investigation the attachment flux for the attachment of thorium B atoms (of an approximate concentration of 4x10 3 atoms/cm 3 ) to monodisperes polystyrene aerosols (of a radius from 0,5 to 2,5 μm) in the concentration range 1-30 particles/cm 3 , was directly measured. Steps were taken to prevent the formation of radiolytic nuclei, and all the relevant parameters were measured during the experiments. The attachment between the radioactive atoms and the aerosols was found to be directly proportional to the particle concentration N, as well as to R 2 . The sticking probability of atoms to a particle was found to be of the order of 0,1. The results show that the attachment was found; this was attributed to the attachment of radioactive atoms to agglomerate vapour molecules

  11. Phenomenological study of aerosol dry deposition in urban area: surface properties, turbulence and local meteorology influences

    International Nuclear Information System (INIS)

    Roupsard, P.

    2013-01-01

    Aerosol dry deposition is not much known for urban areas due to the lack of data. Knowledge on this phenomenon is necessary to understand pollutant fluxes in cities and to estimate inhabitant exposition to ionizing radiation of radioactive aerosols. A data providing could enable to enhance dry deposition models for these areas. An original experimental approach is performed to study submicron aerosol dry deposition on urban surfaces. Wind tunnel coupled to in situ experiments give results to study different physical phenomenon governing dry deposition. Dry deposition velocities are measured using aerosol tracers. These data are associated to turbulent and meteorological measured conditions. This database permits to classify the principal physical phenomenon for each experiment type. Finally, different phenomenon must be considered for chronic and acute exposition of urban surfaces to atmospheric particles. (author)

  12. Generation of aerosols: BARC nebulizer and others

    International Nuclear Information System (INIS)

    Soni, P.S.; Raghunath, B.

    1994-01-01

    The concern with atmospheric pollution in recent times has focused attention on aerosols, their distribution pattern after inhalation and the kinetics of their deposition and exclusion from bronchial passages. The technique of radioaerosols for lung imaging is of recent origin. The procedure was proposed as a means of estimating regional ventilation and localizing areas of airway narrowing. The technique is an alternative in the face of non-availability of radioactive gases, especially in developing countries where the cost is the major factor due to economic reasons. Now, it is beyond doubt that radioaerosol lung studies are a potentially valuable tool in the evaluation of respiratory function in health and disease, especially to detect chronic obstructive pulmonary diseases. Also, the administration of a drug by aerosol inhalation provides a convenient method for the treatment of conditions affecting the respiratory system. This write-up will brief us about radioaerosol, its generation and characterisation

  13. Generation of aerosols: BARC nebulizer and others

    Energy Technology Data Exchange (ETDEWEB)

    Soni, P S; Raghunath, B

    1994-07-01

    The concern with atmospheric pollution in recent times has focused attention on aerosols, their distribution pattern after inhalation and the kinetics of their deposition and exclusion from bronchial passages. The technique of radioaerosols for lung imaging is of recent origin. The procedure was proposed as a means of estimating regional ventilation and localizing areas of airway narrowing. The technique is an alternative in the face of non-availability of radioactive gases, especially in developing countries where the cost is the major factor due to economic reasons. Now, it is beyond doubt that radioaerosol lung studies are a potentially valuable tool in the evaluation of respiratory function in health and disease, especially to detect chronic obstructive pulmonary diseases. Also, the administration of a drug by aerosol inhalation provides a convenient method for the treatment of conditions affecting the respiratory system. This write-up will brief us about radioaerosol, its generation and characterisation.

  14. Aerosol typing - key information from aerosol studies

    Science.gov (United States)

    Mona, Lucia; Kahn, Ralph; Papagiannopoulos, Nikolaos; Holzer-Popp, Thomas; Pappalardo, Gelsomina

    2016-04-01

    Aerosol typing is a key source of aerosol information from ground-based and satellite-borne instruments. Depending on the specific measurement technique, aerosol typing can be used as input for retrievals or represents an output for other applications. Typically aerosol retrievals require some a priori or external aerosol type information. The accuracy of the derived aerosol products strongly depends on the reliability of these assumptions. Different sensors can make use of different aerosol type inputs. A critical review and harmonization of these procedures could significantly reduce related uncertainties. On the other hand, satellite measurements in recent years are providing valuable information about the global distribution of aerosol types, showing for example the main source regions and typical transport paths. Climatological studies of aerosol load at global and regional scales often rely on inferred aerosol type. There is still a high degree of inhomogeneity among satellite aerosol typing schemes, which makes the use different sensor datasets in a consistent way difficult. Knowledge of the 4d aerosol type distribution at these scales is essential for understanding the impact of different aerosol sources on climate, precipitation and air quality. All this information is needed for planning upcoming aerosol emissions policies. The exchange of expertise and the communication among satellite and ground-based measurement communities is fundamental for improving long-term dataset consistency, and for reducing aerosol type distribution uncertainties. Aerosol typing has been recognized as one of its high-priority activities of the AEROSAT (International Satellite Aerosol Science Network, http://aero-sat.org/) initiative. In the AEROSAT framework, a first critical review of aerosol typing procedures has been carried out. The review underlines the high heterogeneity in many aspects: approach, nomenclature, assumed number of components and parameters used for the

  15. Observation of aerosol situation on the object 'Ukryttya' at MSDS work session in April 2008

    International Nuclear Information System (INIS)

    Ogorodnikov, B.I.; Khan, V.E.; Krasnov, V.A.; Koval'chuk, V.P.

    2008-01-01

    By means of sampling of radioactive aerosols in BYPASS System it have been shown that in April, 2008 considerable changes of concentration during the operation of Modernized System of Dust Suppression (MSDS), were not observed. Such situation probably is conditioned by the presence of polymer film at the cover of a disintegration of Central Hall and in buttress area. However external environment heavy winds result in rising of aerosol concentration in BYPASS System due to a dust raising in apartments out of MSDS service area

  16. Natural and artificial radioactivity distribution In soil of Fars province (IR)

    International Nuclear Information System (INIS)

    Faghihi, R.; Mehdizadeh, S.; Sina, S.

    2011-01-01

    Fars province is a large populated large province located in the southwest of Iran. This work presents a study of natural and radioactivity levels in soil samples of this province. For this purpose, 126 samples were gathered from different regions of the province and analysed by gamma spectroscopy to quantify radioactivity concentrations of radionuclides using a high-purity germanium detector and spectroscopy system. The results of this investigation show the average concentrations of 271 ± 28 Bq kg -1 , 6.37 ± 0.5 Bq kg -1 , 14.9 ± 0.9 Bq kg -1 and 26.3 ± 1.9 Bq kg -1 for 40 K, 137 Cs, 232 Th and 238 U in soil, respectively. Finally, baseline maps were established for the concentrations of each of the radionuclides in different regions. The absorbed dose rate and the annual effective dose (AED) were also calculated for the radionuclides according to the guidelines of UNSCEAR 2000. The average AED from the radioactivity content of soil in this province was found to be 39.9 ± 1.8 μSv. (authors)

  17. Aerosol behaviour modeling and measurements

    Energy Technology Data Exchange (ETDEWEB)

    Gieseke, J A; Reed, L D [Batelle Memorial Institute, Columbus, OH (United States)

    1977-01-01

    Aerosol behavior within Liquid Metal Fast Breeder Reactor (LMFBR) containments is of critical importance since most of the radioactive species are expected to be associated with particulate forms and the mass of radiologically significant material leaked to the ambient atmosphere is directly related to the aerosol concentration airborne within the containment. Mathematical models describing the behavior of aerosols in closed environments, besides providing a direct means of assessing the importance of specific assumptions regarding accident sequences, will also serve as the basic tool with which to predict the consequences of various postulated accident situations. Consequently, considerable efforts have been recently directed toward the development of accurate and physically realistic theoretical aerosol behavior models. These models have accounted for various mechanisms affecting agglomeration rates of airborne particulate matter as well as particle removal rates from closed systems. In all cases, spatial variations within containments have been neglected and a well-mixed control volume has been assumed. Examples of existing computer codes formulated from the mathematical aerosol behavior models are the Brookhaven National Laboratory TRAP code, the PARDISEKO-II and PARDISEKO-III codes developed at Karlsruhe Nuclear Research Center, and the HAA-2, HAA-3, and HAA-3B codes developed by Atomics International. Because of their attractive short computation times, the HAA-3 and HAA-3B codes have been used extensively for safety analyses and are attractive candidates with which to demonstrate order of magnitude estimates of the effects of various physical assumptions. Therefore, the HAA-3B code was used as the nucleus upon which changes have been made to account for various physical mechanisms which are expected to be present in postulated accident situations and the latest of the resulting codes has been termed the HAARM-2 code. It is the primary purpose of the HAARM

  18. Studies to determine the deposition velocity of aerosols on vegetation and other sampling areas

    International Nuclear Information System (INIS)

    Jonas, R.; Vogt, K.J.

    The deposition velocity of aerosols with diameters between 0.4 and 17 μm, required for environmental exposure calculations, was experimentally determined in fifty-two field tests from 1975 to 1980. The results of the deposition experiments on grass indicate that the deposition velocity is proportional to the friction velocity and depends on both the vegetation dry mass (v/sub g/ approx. D 0 8 ) and on the aerosol diameter. The deposition velocity can be represented as an inverse polynominal function of the 3rd order as a function of the aerosol diameter. This demonstrated that the deposition velocity increases especially rapidly (by a factor of about 10) between diameters of 4 and 6 μm, for which turbulence deposition is characteristic, while the rise diminishes for larger particles, for which sedimentation is important. The deposition velocity on grass can be regarded as a characteristic value for environmental exposure calculations. It can be assumed that in the normal operation of nuclear power stations and in the case of incidents in which radioactive substances are released in a filtered condition, a particle diameter of 3 μm is not exceeded and differences in friction velocity and dry mass are cancelled out in the temporal mean. At a mean friction velocity of 27 cm/s and a representative dry mass for grass of 0.017 g/cm 2 deposition velocities of 0.01, 0.02, 0.05, 0.42 and 4.6 cm/s resulted, corresponding to particle diameters of 1, 2, 3, 5 and 10 μm. This indicates that the reference value of 0.1 cm/s, given in the Allgemeine Berechnungsgrundlage (general calculation basis) for the normal operation of nuclear power stations, is sufficiently conservative. The mean deposition velocity for clover was higher by a factor of approximately 2, for artificial interfaces (smooth and structured metals, filters) and soil by a factor of approximately 3 and thus 2 lower than for grass

  19. Radioactivity and environment: example of the Brest roads

    International Nuclear Information System (INIS)

    Le Roux, J.M.

    2000-01-01

    In this work, the author makes, first, an inventory of the natural and artificial sources of radiations. Then, in a second chapter, he presents the characteristics, origin and management of radioactive wastes. Chapter 3 treats of the radiological monitoring of the environment with the example of the Brest gulf (Brittany, Western France). The last chapter presents the role of pharmacists in the supply of potassium iodide tablets, in public information and in the participation to consultation networks about the risks of nuclear energy and radioactivity. (J.S.)

  20. MODIS 3km Aerosol Product: Algorithm and Global Perspective

    Science.gov (United States)

    Remer, L. A.; Mattoo, S.; Levy, R. C.; Munchak, L.

    2013-01-01

    After more than a decade of producing a nominal 10 km aerosol product based on the dark target method, the MODIS aerosol team will be releasing a nominal 3 km product as part of their Collection 6 release. The new product differs from the original 10 km product only in the manner in which reflectance pixels are ingested, organized and selected by the aerosol algorithm. Overall, the 3 km product closely mirrors the 10 km product. However, the finer resolution product is able to retrieve over ocean closer to islands and coastlines, and is better able to resolve fine aerosol features such as smoke plumes over both ocean and land. In some situations, it provides retrievals over entire regions that the 10 km product barely samples. In situations traditionally difficult for the dark target algorithm, such as over bright or urban surfaces the 3 km product introduces isolated spikes of artificially high aerosol optical depth (AOD) that the 10 km algorithm avoids. Over land, globally, the 3 km product appears to be 0.01 to 0.02 higher than the 10 km product, while over ocean, the 3 km algorithm is retrieving a proportionally greater number of very low aerosol loading situations. Based on collocations with ground-based observations for only six months, expected errors associated with the 3 km land product are determined to be greater than for the 10 km product: 0.05 0.25 AOD. Over ocean, the suggestion is for expected errors to be the same as the 10 km product: 0.03 0.05 AOD. The advantage of the product is on the local scale, which will require continued evaluation not addressed here. Nevertheless, the new 3 km product is expected to provide important information complementary to existing satellite-derived products and become an important tool for the aerosol community.

  1. Radioactive contamination of the environmental samples in Hanoi in 1989

    International Nuclear Information System (INIS)

    Dang Huy Uyen; Bui Van Loat; Dang Phuong Nam; Cao Anh Duc; Pham Quang Dien; Nguyen Hao Quang

    1990-01-01

    More than 30 environmental samples from soil, paddy, rice, fruits, vegetables and beans, sesame, tea, bananas, fishes at Hanoi markets in 1989 were analysed by gamma ray spectrometry with the low background system for studying natural and artificial radioactive elements. Among several samples from Hanoi in such kind as cultivated soils, tea, dried bamboo shoots, isotope Cs 137 that used be generated from nuclear explosives was found with contents (30 - 1000) x 10 -5 Bq/g; Cs 137 contents in Japanese rice (0.4 - 3) x 10 -5 Bq/g. Cs 137 is radioactive so Cs 137 contents in Vietnamese rice are 300 times higher than Cs 137 contents in Japanese rice but they are hundred times lower than international standard. Among vegetables, fruits, shrimps, fishes in Hanoi markets, artificial isotopes were not found and natural isotopes were few. Even radioactive daughter and granddaughter in uranium series in potatoes were not found. In some samples K 40 was also appeared, for example in cultivated soils (0.78 Bq/g), in dried bamboo shoots (0.73 Bq/g). (author). 2 refs., 3 figs

  2. Efficiency of the collection of aerosol detectors used in EDF nuclear power stations

    International Nuclear Information System (INIS)

    Fauvel, S.; Gensdarmes, F.; Valendru, N.

    2009-01-01

    The authors report an investigation performed to asses the efficiency of different radioactive aerosol detectors by comparing the mass concentration sampled by the tested detectors with the reference mass concentration. The authors describe the measurement installation and protocol, and discuss the results obtained for different grain sizes and different renewal rates

  3. Protection of environmental contamination by radioactive materials and remediation of environment

    International Nuclear Information System (INIS)

    2003-05-01

    This report consisted of the environmental contamination of radioactive and non-radioactive materials. 38 important accident examples of environmental contamination of radioactive materials in the world from 1944 to 2001 are stated. Heavily polluted areas by accidents are explained, for example, Chernobyl, atomic reactor accidents, development of nuclear weapon in USA and USSR, radioactive waste in the sea. The environmental contamination ability caused by using radioactive materials, medical use, operating reactor, disposal, transferring, crashing of airplane and artificial satellite, release are reported. It contains measurements and monitor technologies, remediation technologies of environmental contamination and separation and transmutation of radioactive materials. On the environmental contamination by non-radioactive materials, transformation of the soil contamination in Japan and its control technologies are explained. Protection and countermeasure of environmental contamination of radioactive and non-radioactive materials in Japan and the international organs are presented. There are summary and proposal in the seventh chapter. (S.Y.)

  4. Radioactive waste and transport. Chapter 6

    International Nuclear Information System (INIS)

    1978-01-01

    A brief definition of the nature of radioactive waste is followed by a more detailed discussion of high level waste, its composition the amounts involved, storage in liquid and in solid form and the storage of non-reprocessed spent fuel. The final disposal of high level waste in deep geological structures is then described, based on the Swedish KBS study. The effectiveness of the artificial and natural barriers in preventing the radioactive substances from reaching the biosphere is discussed. American and Swedish risk analyses are briefly discussed, and practical experience presented. Low and medium level wastes are thereafter treated in a similar, though briefer manner. Transport of radioactive materials, fresh fuel, spent fuel and waste is then dealt with. Regulations for the containers and their tests are briefly presented and the risk of accidents, theft and sabotage during transport are discussed. (JIW)

  5. General radioactive contamination of the biosphere in the Netherlands

    International Nuclear Information System (INIS)

    1980-01-01

    The Coordinating Committee for the Monitoring of Radioactive and Xenobiotic Substances (C.C.R.X.) reports the results of the radioactivity measurements in 1979. These are divided into measurements for the National Measuring Programme and Additional Measurements. The former include the analyses considered essential for an efficacious control of the radioactivity of the biosphere and are performed in air, soil, surface water, milk and in deposition on the surface of the earth. Samples of milk and grass from the surroundings of nuclear reactors have also been analysed. Additional measurements comprises orientating research for specific radionuclides which may be present in some samples, and other investigations which may procure useful information. Results of determinations of radionuclides in some fishery-products from the Dutch waters are given in view of the potential which some marine organisms have to concentrate fission products and especially activated corrosion products from nuclear installations. After a discussion of the results for the National Measuring Programme, a calculation is given of the total artificial radioactivity in the average Dutch diet in 1979 and of the total mean annual radiation dose the Dutch population received as a result of the presence of artificial radionuclides. Different methods studied to calculate the bone dose due to Sr-90 in the diet are outlined as an appendix. (Auth.)

  6. Artificial radioactivity in the sea near Japan

    Energy Technology Data Exchange (ETDEWEB)

    Miyake, Y; Sugiura, Y; Kameda, K

    1955-01-01

    Sea water collected around the Bikini Atoll from July to September 1954, was analyzed for total radioactivity by adding 2 g solid NH/sub 4/Cl, 1 ml of an aqueous solution of Ferric alum (86.3 g/l), and 1 ml of BaCl/sub 2/ solution (17.8 g/l) to 1 l of H/sub 2/O heated to 60 to 70 while being stirred. NH/sub 4/OH was added until the solution was faintly pink to phenolphthalein. After 2-min boiling the precipitate settled on standing for several hours at room temperature before being filtered on a filter disk lain above a glass filter. Counting rates of 2.1 +- 1.6 to 140.8 +- 6.8 counts/min/l were obtained.

  7. Forest decline through radioactivity

    International Nuclear Information System (INIS)

    Reichelt, G.; Kollert, R.

    1985-01-01

    Is more serious damage of forest observed in the vicinity of nuclear reactors. How are those decline patterns to be explained. Does the combined effect of radioactivity and different air pollutants (such as nitrogen oxides, sulfur dioxide, oxidants etc.) have an influence in the decline of the forest. In what way do synergisms, i.e. mutually enhanced effects, participate. How does natural and artificial radioactivity affect the chemistry of air in the polluted atmosphere. What does this mean for the extension of nuclear energy, especially for the reprocessing plant planned. Damage in the forests near nuclear and industrial plants was mapped and the resulting hypotheses on possible emittors were statistically verified. Quantitative calculations as to the connection between nuclear energy and forest decline were carried through: they demand action. (orig./HP) [de

  8. Comparative study between radioactive contamination in milk powder by chernobyl accident [137Cs] and natural radioactivity [40K

    International Nuclear Information System (INIS)

    Navarrete, J.M.; Martinez, T.; Cabrera, L.

    2005-01-01

    After the Chernobyl accident in 1986, Mexico imported from an European country 28,000 Tons of contaminated milk powder with the fission product 137 CS. When the contamination was detected, the alarm among the authorities and population spread out very quick and of course the product was retired at once from the foodstuff market. Nevertheless, the public panic grew up in such a manner, that even the way to manage and to dispose safely this material, considered highly dangerous, was largely discussed. Now, about two decades ago from this event, a study has been performed to compare the level of radioactivity due to both radioisotopes present in one saved sample: the artificial contaminant 137 CS, beside the natural, all around present 40 K, in order to evaluate in a more realistic way how risky was the management, possible consumption, and final disposition of this nourishment. This paper considers results obtained within an uncertainty degree equal to ±5%, and set up conclusions by comparing artificial and natural radioactivity present in that contaminated milk powder.

  9. Measurement of radioactive nuclides in the `Mayak` region

    Energy Technology Data Exchange (ETDEWEB)

    Myasoedov, B F [V.I. Vernadsky Inst. of Geochemistry and Analytical Chemistry, Russian Academy of Sciences, Moscow (Russian Federation); Novikov, A P [V.I. Vernadsky Inst. of Geochemistry and Analytical Chemistry, Russian Academy of Sciences, Moscow (Russian Federation)

    1997-03-01

    The study of environmental contamination caused by anthropogenic impact and, primarily, by radioactive nuclides is one of the main scientific problems facing contemporary science. Radioecological monitoring, decision making on remediation of polluted areas need detailed information about distribution of radioactive nuclides in the terrestrial and aquatic ecosystems, knowledge about radioactive nuclide occurrence forms and migration patterns. Experimental tests of nuclear and thermonuclear weapon in atmosphere and underground, nuclear power engineering and numerous accidents that took place at the nuclear power plants (NPP), unauthorized dump of radioactive materials in various places of the ocean and pouring off the strongly dump of radioactive wastes from ships and submarine equipped with nuclear power engines made artificial radionuclides a constant and unretrievable component of the modern biosphere, becoming an additional unfavorable ecological factor. As regards Former Sovient Union (FSU) the most unfavorable regions are Southern Ural, zones suffered from Chernobyl Accident, Altay, Novaya Zemlya, some part of West Siberia near Seversk (Tomsk-7) and Zheleznogorsk (Krasnoyarsk-26). (orig.)

  10. Measurement of radioactive nuclides in the 'Mayak' region

    International Nuclear Information System (INIS)

    Myasoedov, B.F.; Novikov, A.P.

    1997-01-01

    The study of environmental contamination caused by anthropogenic impact and, primarily, by radioactive nuclides is one of the main scientific problems facing contemporary science. Radioecological monitoring, decision making on remediation of polluted areas need detailed information about distribution of radioactive nuclides in the terrestrial and aquatic ecosystems, knowledge about radioactive nuclide occurrence forms and migration patterns. Experimental tests of nuclear and thermonuclear weapon in atmosphere and underground, nuclear power engineering and numerous accidents that took place at the nuclear power plants (NPP), unauthorized dump of radioactive materials in various places of the ocean and pouring off the strongly dump of radioactive wastes from ships and submarine equipped with nuclear power engines made artificial radionuclides a constant and unretrievable component of the modern biosphere, becoming an additional unfavorable ecological factor. As regards Former Sovient Union (FSU) the most unfavorable regions are Southern Ural, zones suffered from Chernobyl Accident, Altay, Novaya Zemlya, some part of West Siberia near Seversk (Tomsk-7) and Zheleznogorsk (Krasnoyarsk-26). (orig.)

  11. Characteristics and Sampling Efficiencies of Two Personal Aerosol Samplers

    Science.gov (United States)

    2007-07-01

    stainless steel and plastic; therefore, it can be decontaminated easily by immersing in decontamination solution. 9 PAS-2 PAS-1 Figure 3. Picture of PAS...portable, and easy to use for decontamination . The sampling efficiency tests were conducted with monodisperse 0.5-, 1-, and 2.1-gtm fluorescent...Scientific, Corp., Palo Alto, CA). The PSL aerosols were generated using a 24 jet Collison nebulizer and then passed through a radioactive isotope (Kr-85

  12. Very low level radioactive material

    International Nuclear Information System (INIS)

    Schaller, K.H.; Linsley, G.; Elert, M.

    1993-01-01

    Man's environment contains naturally occurring radionuclides and doses from exposures to these radionuclides mostly cannot be avoided. Consequently, almost everything may be considered as very low level radioactive material. In practical terms, management and the selection of different routes for low level material is confined to material which was subject to industrial processing or which is under a system of radiological control. Natural radionuclides with concentrations reaching reporting or notification levels will be discussed below; nevertheless, the main body of this paper will be devoted to material, mainly of artificial origin, which is in the system involving notification, registration and licensing of practices and sources. It includes material managed in the nuclear sector and sources containing artificially produced radionuclides used in hospitals, and in industry. Radioactive materials emit ionising radiations which are harmful to man and his environment. National and international regulations provide the frame for the system of radiation protection. Nevertheless, concentrations, quantities or types of radionuclide may be such, that the material presents a very low hazard, and may therefore be removed from regulatory control, as it would be a waste of time and effort to continue supervision. These materials are said to be exempted from regulatory control. Material exempted in a particular country is no longer distinguishable from ''ordinary'' material and may be moved from country to country. Unfortunately, criteria for exempting radioactive materials differ strongly between countries and free trade. Therefore there is a necessity for an international approach to be developed for exemption levels

  13. Centennial of the discovery of radioactivity - 1896-1898/1996-1998

    International Nuclear Information System (INIS)

    Bimbot, R.; Casse, M.

    2009-01-01

    This document summarizes the impacts that the discovery of radioactivity in 1896 has had on the scientific world: 1 - historical aspects (biographies of Henri Becquerel, Pierre Curie and Marie Curie-Sklodowska; context; history of radioactivity discovery; examples of radioactive half-lives); 2 - development of matter sciences (radiochemistry; nuclear and particle physics; nuclear and particle astrophysics); 3 - dating and energy applications: isotope dating; power generation (fission, fusion, nuclear reactor components, reactor types, radioactive wastes); 4 - biological, medical and agronomic applications (biological researches, medical diagnosis, clinical exploration and therapies, man's exposure to ionizing radiations, natural and artificial radioactivity, sources, doses and radiation effects, radioactivity in the Saclay area, radioactivity changes with places, research tool in plants biology and agronomic. Reprints of original communications presented by H. Becquerel and P. and M. Curie at the sessions of the French Academy of Sciences between 1896 and 1906, as well as the talks given at the Academy for the funerals of H. Becquerel, are attached to the document. (J.S.)

  14. Application of artificial intelligence to radiation control, (1)

    International Nuclear Information System (INIS)

    Kimura, Yoshitaka; Hasegawa, Keisuke; Ikezawa, Yoshio

    1990-01-01

    Recently artificial intelligence (AI) which has functions of our interpretations and judgments has been applied to various fields of science. In the first application of AI to the transport procedure of the radioactive material, a prototype of expert system was developed with UTI-LISP programming language to appropriately classify mainly the packages and packagings according to regulations for the safe transport of radioactive material. Classification of the packages and packagings for the consignment is mainly determined from input informations such as radionuclides, its activities, states and conveyances through a forward reasoning method of the expert system. The rationalization of practice on our interpretations and judgments for transport of radioactive material including uniformity and reliability of our decision were confirmed as the result of an application to radiation control. (author)

  15. Gross alpha radioactivity of drinking water in Venezuela

    International Nuclear Information System (INIS)

    Sajo-Bohus, L.; Gomez, J.; Greaves, E.D.; Herrera, O.; Salazar, V.; Smith, A.

    1997-01-01

    Bottled mineral water is consumed by a large population in Venezuela. The alpha emitters concentration was measured in samples of bottled water and water springs collected near the surface. Approximately 30% of the total mineral water suppliers was monitored. a database on natural and artificial radioactivity in drinking water was produced. Results indicate that 54% of the waters sampled contain a total alpha radioactivity of less than 0.185 Bql -1 and only 12% above 0.37 Bql -1 . Our results revealed a total annual dose of 2.3 mSv year -1 . (author)

  16. On the environmental pollution and radioactivity within the territory of Russia in October, 1992

    International Nuclear Information System (INIS)

    Ovanesyants, A.M.; Belova, N.A.; Ivanov, M.N.

    1993-01-01

    Points of Russia were indicated where the maximum permissible concentration limits of pollutants were found to be exceeded. Causes of the observed incidents were described. Pollution of the atmospheric air, soils and surface waters was presented for the october, 1992. Daily concentrations of the radioactive aerosols in the atmospheric air were equal to the background values as well as their fallout. High radioactivity in Chita and Rostov cities were explaned by natural origin factors (meteorological conditions)

  17. The dispersion of radioactive aerosols in fires

    International Nuclear Information System (INIS)

    Buijs, K.; Chavane de Dalmassy, B.; Pickering, S.

    1989-01-01

    Experimental results are reported on the resuspension, due to fire, of radioactive nuclear fuel particles from a variety of substrates. Experiments were carried out both on large and small scale. In small-scale fires uranium-plutonium oxide particles were used and in the large-scale fires cerium-europium oxide particles were used. The mechanisms of particle resuspension were investigated in separate series of experiments. It was found that in small-scale fires up to 20% of the particle inventory can be resuspended and in large-scale fires up to 75%. In both cases most of the resuspended material deposits within the fire chamber and a maximum of 2% is carried into the ventilation duct at the outlet of the fire chamber. The predominant resuspension mechanisms are bubble bursting in small-scale fires and turbulence in large-scale fires. (orig.)

  18. United role of radon decay products and nano-aerosols in radon dosimetry

    Science.gov (United States)

    Smerajec, M.; Vaupotič, J.

    2012-04-01

    The major part of human exposure to natural radiation originates from inhalation of radon (Rn) and radon short-lived decay products (RnDP: 218Po, 214Pb, 214Bi and 214Po). RnDP are formed as a result of α-transformation of radon. In the beginning they are positive ions which neutralize and form clusters with air molecules, and later partly attach to background aerosol particles in indoor air. Eventually, they appear as radioactive nano-aerosols with a bimodal size distribution in ranges of 1-10 nm (unattached RnDP) and of 200-800 nm (attached RnDP). When inhaled, they are deposited in the respiratory tract. Deposition is more efficient for smaller particles. Therefore, the fraction (fun) of the unattached RnDP, which appears to be influenced by the number concentration and size distribution of general (background) aerosols in the ambient air, has a crucial role in radon dosimetry. Radon, radon decay products and general aerosols have been monitored simultaneously in the kitchen of a typical rural house under real living conditions, also comprising four human activities generating particular matter: cooking and baking, as two typical activities in kitchen, and cigarette smoking and candle burning. In periods without any human activity, the total number concentration of general aerosol ranged from 1000 to 3000 cm-3,with the geometric mean of particle diameter in the range of 60-68 nm and with 0.1-1 % of particles smaller than 10 nm. Preparation of coffee changed the concentration to 193,000 cm-3, the geometric mean of diameter to 20 nm and fraction of particles smaller than 10 nm to 11 %. The respective changes were for baking cake: 503,000 cm-3, 17 nm and 19 %, for smoking:423,000 cm-3, 83 nm and 0.4 %, and forcandle burning: 945,000 cm-3, 8 nm and 85 %. While, as expected, a reduction of fun was observed during cooking, baking and smoking, when larger particles were emitted, fun did not increase during candle burning with mostly particles smaller than 10 nm

  19. Distribution of stable and radioactive metals among the biomass compartments of the macrophytes of the Yenisei river and estimation of the dose rate

    International Nuclear Information System (INIS)

    Zotina, T.A.; Bolsunovskiy, A.Ya.; Sukovatyj, A.G.

    2008-01-01

    Artificial radioactive metals are annually detected in the biomass of submerged macrophytes in the zone radioactive contamination of the Yenisei river. It has been shown by other authors that metals are not uniformly distributed in the biomass of aquatic macrophytes. In this research the distribution of stable and radioactive isotopes of metals was investigated among the biomass compartments of the macrophytes from the Yenisei river with chemical fractionation technique. Dose rates from the intra- and extracellular radionuclides have been estimated. According to the data obtained the distribution of metals among intra- and extracellular compartments was different. The major portion of Co, Mn and Zn was accumulated in the biomass in more mobile form, than Cr and Fe. Artificial radioactive isotopes were detected in the same compartments as stable metals. Essential portion of artificial radionuclides and stable metals was detected in the particles of seston, attached to the surface of the macrophytes.

  20. Radiation protection. Radioactivity and health. 3. ed.

    International Nuclear Information System (INIS)

    Feinendegen, L.E.; Feldmann, A.; Muench, E.; Paschke, M.

    1986-09-01

    This booklet makes an attempt at elucidating the mutual influence of radioactivity and health in a way which is understandable to the non-expert. The basics of radioactivity are briefly explained by way of introduction, the next item to be described is exposure of man to natural and artificial radiation. Somatic and genetic effects of radiation on man are subsequently discussed. The whole area of radioecology - starting with radioactive discharge from nuclear plants and going on to the determination of man's exposure to radiation - is covered and supplemented by a description of the risks of radiation therapy. All this serves to describe the results of long-term research on questions of the radiobiological risks in an understandable way and provide useful information about this eminently important area. (orig.) [de

  1. Photophoretic velocimetry for the characterization of aerosols.

    Science.gov (United States)

    Haisch, Christoph; Kykal, Carsten; Niessner, Reinhard

    2008-03-01

    Aerosols are particles in a size range from some nanometers to some micrometers suspended in air or other gases. Their relevance varies as wide as their origin and composition. In the earth's atmosphere they influence the global radiation balance and human health. Artificially produced aerosols are applied, e.g., for drug administration, as paint and print pigments, or in rubber tire production. In all these fields, an exact characterization of single particles as well as of the particle ensemble is essential. Beyond characterization, continuous separation is often required. State-of-the-art separation techniques are based on electrical, thermal, or flow fields. In this work we present an approach to apply light in the form of photophoretic (PP) forces for characterization and separation of aerosol particles according to their optical properties. Such separation technique would allow, e.g., the separation of organic from inorganic particles of the same aerodynamic size. We present a system which automatically records velocities induced by PP forces and does a statistical evaluation in order to characterize the particle ensemble properties. The experimental system essentially consists of a flow cell with rectangular cross section (1 cm(2), length 7 cm), where the aerosol stream is pumped through in the vertical direction at ambient pressure. In the cell, a laser beam is directed orthogonally to the particle flow direction, which results in a lateral displacement of the particles. In an alternative configuration, the beam is directed in the opposite direction to the aerosol flow; hence, the particles are slowed down by the PP force. In any case, the photophoretically induced variations of speed and position are visualized by a second laser illumination and a camera system, feeding a mathematical particle tracking algorithm. The light source inducing the PP force is a diode laser (lambda = 806 nm, P = 0.5 W).

  2. Artificial radioactive products in the atmosphere at Paris. [In French

    Energy Technology Data Exchange (ETDEWEB)

    Abribat, M; Pouradier, J; Venet, A M

    1952-01-01

    The radioactivity of solid matter in rain water and air collected near Paris in November 1951, and in April and May 1952, follows the same decay law as that observed for fission products after a nuclear detonation in Nevada in November 1951.

  3. Development of the aerosol generation system for simulating the dry deposition behavior of radioaerosol emitted by the accident of FDNPP

    Science.gov (United States)

    Zhang, Z.

    2015-12-01

    A large amount of radioactivity was discharged by the accident of FDNPP. The long half-life radionuclide, 137Cs was transported through the atmosphere mainly as the aerosol form and deposited to the forests in Fukushima prefecture. After the dry deposition of the 137Cs, the foliar uptake process would occur. To evaluate environmental transfer of radionuclides, the dry deposition and following foliar uptake is very important. There are some pioneering studies for radionuclide foliar uptake with attaching the solution containing stable target element on the leaf, however, cesium oxide aerosols were used for these deposition study [1]. In the FDNPP case, 137Cs was transported in sulfate aerosol form [2], so the oxide aerosol behaviors could not represent the actual deposition behavior in this accident. For evaluation of whole behavior of 137Cs in vegetation system, fundamental data for deposition and uptake process of sulfate aerosol was desired. In this study, we developed aerosol generation system for simulating the dry deposition and the foliar uptake behaviors of aerosol in the different chemical constitutions. In this system, the method of aerosol generation based on the spray drying. Solution contained 137Cs was send to a nozzle by a syringe pump and spraying with a high speed air flow. The sprayed mist was generated in a chamber in the relatively high temperature. The solution in the mist was dried quickly, and micro size solid aerosols consisting 137Cs were generated. The aerosols were suctioned by an ejector and transported inside a tube by the dry air flow, then were directly blown onto the leaves. The experimental condition, such as the size of chamber, chamber temperature, solution flow rate, air flow rate and so on, were optimized. In the deposition experiment, the aerosols on leaves were observed by a SEM/EDX system and the deposition amount was evaluated by measuring the stable Cs remaining on leaf. In the presentation, we will discuss the detail

  4. Aerosols from metal cutting techniques typical of decommissioning nuclear facilities - experimental system for collection and characterization

    International Nuclear Information System (INIS)

    Newton, G.J.; Hoover, M.D.; Barr, E.B.; Wong, B.A.; Ritter, P.D.

    1982-01-01

    Decommissioning of radioactively contaminated sites has the potential for creating radioactive and other potentially toxic aerosols. We describe an experimental system to collect and characterize aerosols from metal cutting activities typical of those used in decommissioning of nuclear facilities. A special enclosure was designed for the experiment and consisted of a 2-in. x 4-in. stud frame with double walls of flame retardant polyethylene film. Large plexiglass windows allowed the cutting operations to be directed and filmed. Ventilation was 8500 L/min (300 CFM) exhausted through HEPA filters. Seven cutting techniques were evaluated: pipe cutter, reciprocating saw, band saw, chop saw, oxy-acetylene torch, electric arc cut rod and plasma torch. Two grinding tools were also evaluated. Materials cut were 2-, 3- and 4-in. dia schedule 40, 80 and 180 type 304L stainless steel pipe. Basic studies were done on uncontaminated pipe. Four-inch-diameter sections of schedule 180 type 304L stainless steel pipe with radioactively contaminated internal surfaces were also cut. The experiments controlled important variables including tools, cutting technique, and type and thickness of material. 15 references, 4 figures, 2 tables

  5. Adsorption of NO{sub 2} on carbon aerosols particles at the low ppb-level

    Energy Technology Data Exchange (ETDEWEB)

    Kalberer, M.; Ammann, M.; Baltensperger, U.; Gaeggeler, H.W. [Paul Scherrer Inst. (PSI), Villigen (Switzerland)

    1997-09-01

    The adsorption of NO{sub 2} at the low ppb-level (3-40 ppb) on carbon aerosol particles was investigated. A sticking coefficient of about 2.10{sup -4} was found, similar to that in previous studies using radioactively labeled {sup 13}NO{sub 2}. (author) 2 figs., 2 refs.

  6. Decontamination by foams: a promising treatment for the removal of radioactive dust from gas streams

    International Nuclear Information System (INIS)

    Mitchell, J.P.

    1989-06-01

    Foams provide a promising method for the treatment of gas streams containing radioactive aerosol particles. They contain a very large surface area of liquid-gas interface in small cells; thus it is possible to achieve rapid capture of airborne particles in the liquid phase, particularly if the aerosol can be incorporated in the foam structure. The foam can be collapsed into a small volume of liquid, immobilising any trapped aerosol in a form that may be treated as liquid waste. A review of the literature has been undertaken to define and assess the mechanics of aerosol behaviour in contact with foams. Applications are also examined in which foams have been used to treat aerosols. Key issues are identified which require further study. In particular, the efficiency of sub-micron particle removal can be determined using recently developed analysers and the use of the process gas to generate the foam could have a major impact on the design of commercial units. (author)

  7. Application of artificial neural networks on the characterization of radioactive waste drums; Aplicacao de redes neurais artificiais na caracterizacao de tambores de rejeito radioativo

    Energy Technology Data Exchange (ETDEWEB)

    Potiens Junior, Ademar Jose; Hiromoto, Goro, E-mail: apotiens@ipen.b, E-mail: hiromoto@ipen.b [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2011-10-26

    The methodology consist of system simulation of drum-detector by Monte Carlo for obtention of counting efficiency. The obtained data were treated and a neural artificial network (RNA) were constructed for evaluation of total activity of drum. For method evaluation measurements were performed in ten position parallel to the drum axis and the results submitted to the RNA. The developed methodology showed to be effective for isotopic characterization of gamma emitter radioactive wastes distributed in a heterogeneous way in a 200 litters drum. The objective of this work as to develop a methodology of analyse for quantification and localization of radionuclides not homogeneous distributed in a 200 liters drum based on the mathematical techniques

  8. Some results of the investigation of cumuli natural radioactivity

    International Nuclear Information System (INIS)

    Styro, B.I.; Amiranashvili, A.G.

    1979-01-01

    When aircraft sounding cumuli in the eastern regions of the Georgian SSR during 1973-1977 about 70 vertical distribution profiles of radon decay products α-radioactivity for cloud drops and 50 profiles for the cloud medium were obtained. It was determined that in cumuli in a developed phase there exist 4 types of natural radionuclide vertical distribution. It was established that the accumulation of natural radioactivity takes place mainly in the lower part of the cloud, incidentally the radionuclide accumulation level appears to grow with the cloud power. The radioactivity of cloud drops on the average decreases greatly with height in the lower part of the cloud, and in the middle and upper parts it changes vertically insignificantly. The value of the specific radioactivity of the cloud water in different parts of the cloud varies on the average from (4.4+-0.9)x10 -10 up to (1.2+-0.2)x10 -10 Ci/g. The parameter of the nonradioactive removal of radioactive aerosols by drops and the effective rate of the vertical air current in cumuli clouds were calculated. Estimation of the radon current through the cloud bottom was performed

  9. Transportation of radioactive elements

    International Nuclear Information System (INIS)

    Thubert, Francis; Rentien, Guy; Jacquet, Michel

    1981-01-01

    The production and marketing of artificial radioactive elements engaged in by the 'Office des Rayonnements Ionisants' requires the use of specially designed packagings and assorted means of transport. The authors begin by describing the different kinds of products involved and the forms of packagings needed, and go on to discuss the various means of transport used, underlining the fact that, in terms of number and gravity, the incidents that have occurred to date have indeed been few and far between [fr

  10. The radioactivity of the sea

    International Nuclear Information System (INIS)

    Walker, M.I.; Rose, K.S.B.

    1990-01-01

    The radioactivity in the world's surface sea water averages 13.6 Bq/kg of water. Over 88% of this activity arises from a single natural radionuclide, 40 K, and 7% of the remainder results from nuclear weapon test fallout. Variations in the radioactivity occur due to changes in salinity, weapon test fallout and discharges of artificial radionuclides, and are examined here on the basis of published measurements. The most radioactive sea identified by these measurements is the Dead Sea, which averages 178 Bq/kg due to its high salinity. Other enclosed, highly saline waters can be expected to have similar levels. The radioactivity in open seas varies within a much narrower range, generally within 20% of the world average. The highest averages are found in the Persian Gulf (22 Bq/kg), the Red Sea (15 Bq/kg) and the Eastern Mediterranean (14.6 Bq/kg). The Irish Sea averaged 13.7 Bq/kg in 1987, with the effect of the Sellafield discharges being partly offset by lower than average salinity. Although higher levels occurred in the Irish Sea during the 1970s when the Sellafield discharges were higher, the average level has always been much less than that in the Dead Sea, so that the Irish Sea has never been the most radioactive sea in the world. Exceptionally low levels of radioactivity (4 Bq/kg) occur in the Baltic Sea due to dilution by fresh water. (author)

  11. 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)

  12. Survey monitoring of environmental radioactivity in Daegu area

    Energy Technology Data Exchange (ETDEWEB)

    Kang, H. D.; Lee, S. Y. [Kyungpook National Univ., Daegu (Korea, Republic of)

    1998-01-15

    The objectives of the project are to monitor an abnormal radiation level in Taegu and Kyungpook region, and to enhance our ability to prepare for the radiological emergency situation by establishing the radioactivity monitoring system in Taegu and Kyungpook region. Gross beta activities were measured and gamma radionuclides were analysed for the environmental samples of air-borned dust. precipitation. fallout and drinking water collected in Taegu radioactivity monitoring center. and gamma exposure rates were also measured. To establish the basic data base on the environmental radioactivity, gamma radionuclide analyses were carried out for the samples of soil, drinking water, grain, vegetable, milk, and fish which were obtained from 31 different areas, and the spatial gamma exposure rates from 61 different points were also measured in Taegu and Kyungpook region. In conclusion, it didn't appear any evidence for newly pollution of artificial radioactivity in Taegu and Kyungpook region.

  13. Influence of the atmospheric aerosol and air pollution on solar albedo of the earth. Vol. 4

    International Nuclear Information System (INIS)

    Mayhoub, A.B.; Mohamed, K.S.

    1996-01-01

    The effect of increasing atmospheric aerosol and air pollutant concentration on the solar albedo and consequently upon the heat budget near the earth's surface is studied. The magnitude of aerosol absorption coefficient to back-scattering coefficient B ab /B bs is calculated. This study will be used to estimate atmospheric stability categories and other meteorological parameters which are affected by thermal state radiation balance of the atmosphere as mixing and inversion height of Inshas nuclear reactor site. Consequently, concentration distribution of radioactive release from Inshas can be evaluated.. 4 figs., 5 tabs

  14. Influence of the atmospheric aerosol and air pollution on solar albedo of the earth. Vol. 4

    Energy Technology Data Exchange (ETDEWEB)

    Mayhoub, A B; Mohamed, K S [Mathematics and Theoretical Physics Department, Nuclear Research Center, Atomic Energy Auhtority, Cairo, (Egypt)

    1996-03-01

    The effect of increasing atmospheric aerosol and air pollutant concentration on the solar albedo and consequently upon the heat budget near the earth`s surface is studied. The magnitude of aerosol absorption coefficient to back-scattering coefficient B{sub ab}/B{sub bs} is calculated. This study will be used to estimate atmospheric stability categories and other meteorological parameters which are affected by thermal state radiation balance of the atmosphere as mixing and inversion height of Inshas nuclear reactor site. Consequently, concentration distribution of radioactive release from Inshas can be evaluated.. 4 figs., 5 tabs.

  15. A study of regional-scale aerosol assimilation using a Stretch-NICAM

    Science.gov (United States)

    Misawa, S.; Dai, T.; Schutgens, N.; Nakajima, T.

    2013-12-01

    Although aerosol is considered to be harmful to human health and it became a social issue, aerosol models and emission inventories include large uncertainties. In recent studies, data assimilation is applied to aerosol simulation to get more accurate aerosol field and emission inventory. Most of these studies, however, are carried out only on global scale, and there are only a few researches about regional scale aerosol assimilation. In this study, we have created and verified an aerosol assimilation system on regional scale, in hopes to reduce an error associated with the aerosol emission inventory. Our aerosol assimilation system has been developed using an atmospheric climate model, NICAM (Non-hydrostaric ICosahedral Atmospheric Model; Satoh et al., 2008) with a stretch grid system and coupled with an aerosol transport model, SPRINTARS (Takemura et al., 2000). Also, this assimilation system is based on local ensemble transform Kalman filter (LETKF). To validate this system, we used a simulated observational data by adding some artificial errors to the surface aerosol fields constructed by Stretch-NICAM-SPRINTARS. We also included a small perturbation in original emission inventory. This assimilation with modified observational data and emission inventory was performed in Kanto-plane region around Tokyo, Japan, and the result indicates the system reducing a relative error of aerosol concentration by 20%. Furthermore, we examined a sensitivity of the aerosol assimilation system by varying the number of total ensemble (5, 10 and 15 ensembles) and local patch (domain) size (radius of 50km, 100km and 200km), both of which are the tuning parameters in LETKF. The result of the assimilation with different ensemble number 5, 10 and 15 shows that the larger the number of ensemble is, the smaller the relative error become. This is consistent with ensemble Kalman filter theory and imply that this assimilation system works properly. Also we found that assimilation system

  16. Preparatory studies for modelling steam condensation on soluble aerosols

    International Nuclear Information System (INIS)

    Dunbar, I.H.

    1988-01-01

    Of the fission products which would be released from the core of an LWR in the event of a severe accident, only the noble gases and possibly some of the iodine (depending on chemical form) are likely not to be in the form of aerosols when they reach the containment building atmosphere. Therefore in order to predict the extent of fission product retention on containment building internal structures, one needs to have a good understanding of aerosol deposition processes and of the factors which affect them. Following a severe accident in an LWR, a major component of the containment atmosphere will be steam. If the thermodynamic conditions allow condensation of this steam, this condensation is most likely to occur on the aerosol particles. A major component of the aerosol formed during the in-vessel release following a severe reactor accident will be fission product caesium. It is believed that much of this will enter the containment in the form of the hydroxide which has a great affinity for water, so particle growth due to steam condensation is likely to be a very important mechanism for retaining radioactive caesium within the containment builing. The author provides a systematic review of the basic chemical and physical issues which must be addressed if the phenomena are to be modelled accurately, and gives recommendations on how computer models of condensation onto soluble aerosols should be constructed. He proposes also to perform a systematic review of the existing literature and to perform small-scale thermodynamic experiments wherever important gaps in the data base are discovered

  17. Studies on the radioactive contamination due to nuclear detonations II. Preliminary findings on the radioactive fallout due to nuclear detonations

    Energy Technology Data Exchange (ETDEWEB)

    Nishiwaki, Yasushi [Nuclear Reactor Laboratory, Tokyo Institute of Technology, Tokyo (Japan); Nuclear Reactor Laboratoroy, Kinki University, Fuse City, Osaka Precture (Japan)

    1961-11-25

    Since we have detected a considerable amount of artificial radioactivity in the rain in spring 1954, it has become one of the most important items, from the health physics point of view, to continue measurements of radioactivity in the rain and in the atmosphere. To watch out the radioactive contamination of our environment due to repeated nuclear weapons testings in other countries was also considered to be important from the nuclear engineering point of view, in the sense that the permissible allowances of the radioactivity for the peaceful uses of atomic energy might be lowered if the degree of radioactive contamination due to nuclear testings should continue to increase gradually and indefinitely. If the permissible level were lowered, the cost for radiation protection may be expected to increase at the peaceful uses of atomic energy and should the radioactive contamination increase seriously in the future, it was anticipated that we may have to face a very difficult situation in designing the atomic energy facilities for peaceful purposes in our country. From these points of views, we have been continuing measurements of the radioactivity in the rain in Osaka, Japan since the spring of 1954. Some of the preliminary findings are introduced in this paper.

  18. Studies on the radioactive contamination due to nuclear detonations II. Preliminary findings on the radioactive fallout due to nuclear detonations

    International Nuclear Information System (INIS)

    Nishiwaki, Yasushi

    1961-01-01

    Since we have detected a considerable amount of artificial radioactivity in the rain in spring 1954, it has become one of the most important items, from the health physics point of view, to continue measurements of radioactivity in the rain and in the atmosphere. To watch out the radioactive contamination of our environment due to repeated nuclear weapons testings in other countries was also considered to be important from the nuclear engineering point of view, in the sense that the permissible allowances of the radioactivity for the peaceful uses of atomic energy might be lowered if the degree of radioactive contamination due to nuclear testings should continue to increase gradually and indefinitely. If the permissible level were lowered, the cost for radiation protection may be expected to increase at the peaceful uses of atomic energy and should the radioactive contamination increase seriously in the future, it was anticipated that we may have to face a very difficult situation in designing the atomic energy facilities for peaceful purposes in our country. From these points of views, we have been continuing measurements of the radioactivity in the rain in Osaka, Japan since the spring of 1954. Some of the preliminary findings are introduced in this paper

  19. MDS G(N) fast differentiation between natural and artificial gamma radiation with a new class of mobile instruments

    International Nuclear Information System (INIS)

    Katzung, W.; Bottcher, J.

    2009-01-01

    A State-of-the-Art tool used for detecting and tracking artificial gamma radiation out of a helicopter or a vehicle is the MDS G(N) - Mobile Detection System. A highly sensitive scintillation detector detects a significant artificial gamma radiation on the ground even if the helicopter is travelling at high speed. The GPS-aided system visualizes the measured values on a moveable map displayed on the screen of a notebook every second. The colours of the continuously entered points do represent adjustable alarm thresholds. This way, location and intensity of an unknown radioactive source or a radioactive contamination can be determined very quickly. The NBR-technology (Natural Background Rejection) which is used here leads to expressive measurement results differentiating between artificial and natural gamma radiation. Additional He-3 detectors allow simultaneously the detection of neutrons. The NBR principle - developed by Thermo Scientific - stands out for its very short response times. Thus, artificial radiation can be detected reliably within seconds - even when the unit is operated by untrained staff. Unlike traditional analytic measuring techniques, the NBR method is able to detect artificial radiation sources hidden or strongly shielded gamma sources clearly from the natural background radiation. The measuring range from 1 nSv/h to 20 ?Sv/h and is extended to 1 Sv/h with a Geiger Mueller counting tube. The sensitivity amounts to max. 20000 cps (referred to 1 ?Sv/h for Cs-137). The NBR- technique is well-proven and tested for: tracking hidden radiation sources, even such ones with low activity or which are shielded, detection of artificial radiation portions in the range of the natural background, reliably measuring the ambient equivalent dose rate in the range of the natural background, fast detection of artificial radioactivity out of helicopters and vehicles.(author)

  20. Preparation of radioactive tracer for studying sediment movement

    International Nuclear Information System (INIS)

    Hussain, S.D.; Ghauri, G.A.; Qureshi, M.H.; Khan, N.A.

    1983-06-01

    In order to study the movement of sediment in harbours, estuaries and streams, artificial sediment in the form of glass is prepared. A preselected nuclide is added to the glass during its manufacture. The density and size distribution of the glass particles is method with that of the natural sediment. The activation of the artificial sediment in a reactor changes the nuclide into a radioactive isotope thereby tagging it and making it possible to trace its movement with suitable radiation detector. The method of tracer preparation is described with special reference to sadiment movement studies at Karachi harbour. (authors)

  1. Radioactivity in a mountain ecosystem: the Haut Bassin du Var

    International Nuclear Information System (INIS)

    2002-01-01

    After the Chernobyl accident, the IPSN realized a study of the radioactive fallout in the mountain area of the Var (France). Today the main radionuclides are the cesium 134 and 137, others disappeared because of their short half-life. In this paper, the artificial radioactivity of soils and sediments is concerned. The study shows a concentration of the contamination in some specific areas, especially in soils abounding in organic matter. The dose measured can not lead to significant exposures. (A.L.B.)

  2. Nuclear track radiography of 'hot' aerosol particles

    Energy Technology Data Exchange (ETDEWEB)

    Boulyga, S.F.; Kievitskaja, A.I.; Kievets, M.K.; Lomonosova, E.M.; Zhuk, I.V.; Yaroshevich, O.I.; Perelygin, V.P.; Petrova, R.; Brandt, R.; Vater, P

    1999-06-01

    Nuclear track radiography was applied to identify aerosol 'hot' particles which contain elements of nuclear fuel and fallout after Chernobyl NPP accident. For the determination of the content of transuranium elements in radioactive aerosols the measurement of the {alpha}-activity of 'hot' particles by SSNTD was used in this work, as well as radiography of fission fragments formed as a result of the reactions (n,f) and ({gamma},f) in the irradiation of aerosol filters by thermal neutrons and high energy gamma quanta. The technique allowed the sizes and alpha-activity of 'hot' particles to be determined without extracting them from the filter, as well as the determination of the uranium content and its enrichment by {sup 235}U, {sup 239}Pu and {sup 241}Pu isotopes. Sensitivity of determination of alpha activity by fission method is 5x10{sup -6} Bq per particle. The software for the system of image analysis was created. It ensured the identification of track clusters on an optical image of the SSNTD surface obtained through a video camera and the determination of size and activity of 'hot' particles00.

  3. Radioactivity on the surfaces of computer monitors and television screens due to progeny palatal

    International Nuclear Information System (INIS)

    Abdel-Nady, A.; Morsy, A.A.

    2002-01-01

    Computer monitors and television screens can collect radon progeny. Radon decay forming meta-stable progeny, namely, Po-218, Po-214, and Po-210, which are found mostly in positively, charged aerosol particles. These particles are attract by the large negative field of a video display terminals (VDT) leading to buildup of radioactivity on the VDT screen. The charged aerosol particles might drift in the electric field between the VDT and the operator and be accelerated into the operator's face. The aim of this work is to measure these phenomena set of ultra-sensitive TASTRAK detectors used to measure the plate out of positively charged radioactive radon progeny. The track detectors were fixed on the outer monitor screen. For an occupational computer worker spending 200 days per year for 6 hours a day. It was found that the mean dose equivalent was 1.77 mSv, 0.25 mSv/year for normal CRT and LCD monitors respectively

  4. Changes of indoor aerosol characteristics and their associated variation on the dose conversion factor due to radon progeny inhalation

    International Nuclear Information System (INIS)

    Tokonami, Shinji; Ishikawa, Tetsuo; Yonehara, Hidenori; Yamada, Yuji; Matsuzawa, Takao; Iimoto, Takeshi

    2003-01-01

    Since the dose conversion factor (hereafter called DCF) due to radon progeny inhalation is strongly dominated by aerosol characteristics in the environment, it is important to understand the air quality for accurate dose assessment. Thus temporal variations on aerosol concentration, its particle size and its related airborne radioactivities were continuously measured in an actual indoor environment with a relatively high radon concentration. The following human activities were added during the observation period: air-conditioning, removal of aerosol with an air cleaner and ventilation. DCFs based on these activities were evaluated with the latest International Commission of Radiological Protection (ICRP) respiratory tract model and were compared among them. Consequently, the present study has shown that operation of air cleaner enhanced the DCF critically because the unattached fraction increased significantly due to removal of aerosols. (author)

  5. Clinical assessment of a commercial aerosol delivery system for ventilation scanning by comparison with KR-81m

    International Nuclear Information System (INIS)

    Wollmer, P.; Eriksson, L.; Andersson, A.C.

    1984-01-01

    Radioactive aerosols offer a means for steady state ventilation scanning in multiple views. The clinical use of radioaerosol techniques has been hampered by the lack of delivery systems producing sufficiently small particles. If the aerosol contains large particles, heavy deposition occurs in major airways, especially in patients with airways disease. The authors have assessed a new, commercial aerosol delivery system (Syntevent) by comparison with Kr-81m ventilation scanning in 23 patients with airways obstruction. An indirect comparison was also made with a settling bad technique. Ventilation scans in four projections were obtained during continuous inhalation of Kr-81m. Subsequently, the patient inhaled an aerosol labelled with In-113m from the Syntevent system, and aerosol ventilation scans were obtained in the same projections. Spirometry was performed to establish the degree of airways obstruction. The aerosol delineated the ventilated regions of the lungs adequately in all the patients. Deposition of aerosol in larger airways was seen in a few patients only, and this did not impede the interpretation of the scintigram. A quantitative analysis of the penetration of the aerosol to the periphery of the lung failed to demonstrate any significant correlation between particle penetration and airways obstruction. Aerosol penetration was significantly greater (p<0.001) with the Syntevent system than with a settling bag technique

  6. Technical report from Radioactive Waste Management Funding and Research Center

    International Nuclear Information System (INIS)

    2007-10-01

    As the only one Japanese organization specialized in radioactive waste, RWMC (Radioactive Waste Management Funding and Research Center) has been conducting the two major roles; R and D and the fund administration for radioactive waste management. The focus of its studies includes land disposal of LLW (Low-level radioactive wastes) and it has gradually extended to research on management and disposal techniques for high-level (HLW) and TRU wastes and studies on securing and managing the funds required for disposal of these wastes. The present document is the yearly progress report of 2006 and the main activities and research results are included on spent fuel disposal techniques including radon diffusion and emanation problem, performance studies on underground facilities for radioactive waste disposal and its management, technical assessment for geological environment, remote control techniques, artificial barrier systems proposed and its monitoring systems, and TRU disposals. (S. Ohno)

  7. The Invigoration of Deep Convective Clouds Over the Atlantic: Aerosol Effect, Meteorology or Retrieval Artifact?

    Science.gov (United States)

    Koren, Ilan; Feingold, Graham; Remer, Lorraine A.

    2010-01-01

    Associations between cloud properties and aerosol loading are frequently observed in products derived from satellite measurements. These observed trends between clouds and aerosol optical depth suggest aerosol modification of cloud dynamics, yet there are uncertainties involved in satellite retrievals that have the potential to lead to incorrect conclusions. Two of the most challenging problems are addressed here: the potential for retrieved aerosol optical depth to be cloud-contaminated, and as a result, artificially correlated with cloud parameters; and the potential for correlations between aerosol and cloud parameters to be erroneously considered to be causal. Here these issues are tackled directly by studying the effects of the aerosol on convective clouds in the tropical Atlantic Ocean using satellite remote sensing, a chemical transport model, and a reanalysis of meteorological fields. Results show that there is a robust positive correlation between cloud fraction or cloud top height and the aerosol optical depth, regardless of whether a stringent filtering of aerosol measurements in the vicinity of clouds is applied, or not. These same positive correlations emerge when replacing the observed aerosol field with that derived from a chemical transport model. Model-reanalysis data is used to address the causality question by providing meteorological context for the satellite observations. A correlation exercise between the full suite of meteorological fields derived from model reanalysis and satellite-derived cloud fields shows that observed cloud top height and cloud fraction correlate best with model pressure updraft velocity and relative humidity. Observed aerosol optical depth does correlate with meteorological parameters but usually different parameters from those that correlate with observed cloud fields. The result is a near-orthogonal influence of aerosol and meteorological fields on cloud top height and cloud fraction. The results strengthen the case

  8. Radioactivity of some alpha, beta and gamma emitting radionuclides in surface marine sediments of different bays in Algeria

    International Nuclear Information System (INIS)

    Noureddine, A.; Baggoura, B.

    1999-01-01

    Samples of surface (0-15) cm marine sediments of different grain sizes, namely sand, muddy and fine sand, were collected in the western, central and east coast of Algeria, to measure concentrations of natural and artificial radioactivity. The aim of this study is to detect any radioactive contamination, its origin and also to determine the uptake of radioactivity by marine surface sediments

  9. Results of environmental radioactivity measurements in the Member States of the European Community for air - deposition - water - milk. 1981

    International Nuclear Information System (INIS)

    1983-01-01

    This is the 21st report on ambient radioactivity published by the Health and Safety Directorate of the Commission of the European Communities. It was drawn up using the data collected by stations responsible for environmental radioactivity monitoring in Member States. The results are extracts from the data sent to the Commission under Article 36 of the Treaty of Rome establishing the European Atomic Energy Community. The results presented in this report deal with radioactivity of the air, deposition, surface water and milk during 1981 in the ten Member States of the European Community, viz. Belgium, Denmark, Federal Republic of Germany, Greece, France, Ireland, Italy, Luxembourg, the Netherlands and the United Kingdom. The results are presented under four main headings: artificial radioactivity in the air at ground level; artificial radioactivity in deposition; radioactivity of water; radioactivity of milk. The report also contains the list of sampling stations and laboratories, together with a list of publications by Member States in this field. This report places special emphasis on the measurement results for specific radionuclides, but it also contains data on total beta activity so as to ensure continuity vis-a-vis previous and provide comparative values

  10. Radioactivity and nuclear energy

    International Nuclear Information System (INIS)

    Hoffmann, J.; Kuczera, B.

    2001-05-01

    The terms radioactivity and nuclear energy, which have become words causing irritation in the political sphere, actually represent nothing but a large potential for innovative exploitation of natural resources. The contributions to this publication of the Karlsruhe Research Center examine more closely three major aspects of radioactivity and nuclear energy. The first paper highlights steps in the history of the discovery of radioactivity in the natural environment and presents the state of the art in health physics and research into the effects of exposure of the population to natural or artificial radionuclides. Following contributions focus on: Radiochemical methods applied in the medical sciences (diagnostic methods and devices, therapy). Nuclear energy and electricity generation, and the related safety policies, are an important subject. In this context, the approaches and pathways taken in the field of nuclear science and technology are reported and discussed from the angle of nuclear safety science, and current trends are shown in the elaboration of advanced safety standards relating to nuclear power plant operation and ultimate disposal of radioactive wastes. Finally, beneficial aspects of nuclear energy in the context of a sustainable energy policy are emphasized. In particular, the credentials of nuclear energy in the process of building an energy economy based on a balanced energy mix which combines economic and ecologic advantages are shown. (orig./CB) [de

  11. Study of radio-active ions in the atmosphere

    International Nuclear Information System (INIS)

    Renoux, A.

    1965-01-01

    A comparative study is made of active, deposits of radon and thoron in suspension in the atmosphere by means of α radiation counting, using ZELENY tubes, scattering equipment, filter papers or membranes. It has been possible to show the existence of small and large ions which are negative and positive, as well as of neutral radio-active nuclei; their properties are studied. A theoretical interpretation of the results is presented. The average content of radon (using the Ra A concentration) and of Th B in the air has been determined. The radioactive equilibrium between radon and its daughter products in atmospheric air are examined. The techniques developed for active radon and thoron deposits are applied to the study of artificial radio-activity, the analyses being carried out by means of γ spectrometry. (author) [fr

  12. Filtration of aerosols produced by a sodium fire

    International Nuclear Information System (INIS)

    Duverger de Cuy, G.; Colome, J.

    1977-01-01

    The containment system of the Super Phenix reactor takes account of the possibility of contaminated sodium fires, particularly in the vicinity of the fuel storage drum. It is thus necessary to contain the emitted radioactivity associated with a quantity of sodium aerosols of the order of some 10 g/m 3 . Investigations previously carried out had shown that the retention capacity of high-efficiency asbestos filters was clearly insufficient. A new research programme on the filtration of sodium aerosols has thus been worked out with the aim of: gaining a better understanding of the granulometry of the aerosols produced by the fire; checking the efficiency of the new glass-fibre media of which high-efficiency filters are composed; selecting a prefiltering system which, in conjunction with the high-efficiency filter, would ensure a suitable retention capacity for the whole unit. The following prefilters are under investigation: agglomerating cyclones; fabric prefilters (dense filter media - variable density filters - bag filters); water prefilters; sand prefilters. The experimental equipment on which this programme has been based is presented. Results have so far been obtained for agglomerating cyclones (recirculating loop with a cyclone of 95% efficiency), for a number of textile prefilters and for the retention capacity of high-efficiency filters

  13. Nuclear chemistry fifty years after the discovery of artificial radioactivity

    International Nuclear Information System (INIS)

    Lefort, M.

    1984-01-01

    In January 1934, the observation and the chemical identification of radiophosphorus as a reaction product in the bombardment of Aluminium by alpha particles have been the first step of a new scientific branch: Nuclear Chemistry. We describe here how this discovery in itself contains the frame of all the development which has followed. It consisted in four stages, each of them being a crucial starting point. The first one is the possibility for a total balance of the nuclear reaction in the exit channels, so that reaction mechanisms can be studied. The second, the most important perhaps, is the opening of nuclear synthesis. Nuclear chemists can now interfere into nuclear matter and instead of staying as observers of the radioactive decays of natural isotopes, they were able to build up a numerous chart of various nuclear species, going step by step further and further away from the nuclear stability conditions. The third aspect of the discovery was the appearance of a new mode of radioactive decay with the production of the first particle an antimater. 50 years later, the instability due to a much larger excess of protons is known to induce the proton emission radioactivity for new species like 109 I or 115 Cs, in the vicinity of proton unstability. Finally, the last point, so fertile for the future, was the observation of a neutron in the exit channel, so that neutron fluxes could result from alpha induced nuclear reactions and became such a strong tool for the production of transuranium elements and for nuclear fission. In the present survey, the wide interest of the second point, i.e. the nuclear synthesis, is emphasized, as well as the huge change in the technical methods

  14. A survey of radioactive levels of agricultural products in Saitama prefecture

    Energy Technology Data Exchange (ETDEWEB)

    Motegi, Misako; Miyake, Sadaaki; Oosawa, Takashi; Nakazawa, Kiyoaki [Saitama Inst. of Public health, Saitama (Japan)

    1997-09-01

    Past atmospheric nuclear testing which have been conducted frequently, have caused environmental pollution due to the diffusion of radioactive substances into the atmosphere and from the radioactive fallout. The environmental pollution from nuclear testing into the atmosphere has resulted in the radioactive contamination in agricultural products and has continued for a long time. The radioactive contamination of agricultural products occurs through air, water and soil which were contaminated by radioactive fallout. In this paper, for the purpose of analyzing the extent of the radioactive contamination levels in the agricultural products of Saitama Prefecture, spinach, green soybeans, dried shiitake and welsh onion, were selected among products, as the amount of the harvest is abundant in all of Japan. Radioactivity concentration was investigated by gamma-ray spectrometry and radiochemical analysis. The radioactivity concentrations of artificial radioactive nuclides, cesium-137 ({sup 137}Cs) and strontium-90 ({sup 90}Sr), were detected in the range which is considered to be the result of radioactive fallout. Moreover, in order to examine the effect on radioactivity concentrations in agricultural products by culinary processing, the raw agricultural products were boiled, and their radioactivity concentrations were compared with the raw produce. The radioactivity concentrations in the boiled were lower than those in the raw produce. (author)

  15. A survey of radioactive levels of agricultural products in Saitama prefecture

    International Nuclear Information System (INIS)

    Motegi, Misako; Miyake, Sadaaki; Oosawa, Takashi; Nakazawa, Kiyoaki

    1997-01-01

    Past atmospheric nuclear testing which have been conducted frequently, have caused environmental pollution due to the diffusion of radioactive substances into the atmosphere and from the radioactive fallout. The environmental pollution from nuclear testing into the atmosphere has resulted in the radioactive contamination in agricultural products and has continued for a long time. The radioactive contamination of agricultural products occurs through air, water and soil which were contaminated by radioactive fallout. In this paper, for the purpose of analyzing the extent of the radioactive contamination levels in the agricultural products of Saitama Prefecture, spinach, green soybeans, dried shiitake and welsh onion, were selected among products, as the amount of the harvest is abundant in all of Japan. Radioactivity concentration was investigated by gamma-ray spectrometry and radiochemical analysis. The radioactivity concentrations of artificial radioactive nuclides, cesium-137 ( 137 Cs) and strontium-90 ( 90 Sr), were detected in the range which is considered to be the result of radioactive fallout. Moreover, in order to examine the effect on radioactivity concentrations in agricultural products by culinary processing, the raw agricultural products were boiled, and their radioactivity concentrations were compared with the raw produce. The radioactivity concentrations in the boiled were lower than those in the raw produce. (author)

  16. Simultaneous Measurements of Nanoaerosols and Radioactive Aerosols Containing the Short-lived Radon Isotopes.

    Czech Academy of Sciences Publication Activity Database

    Otáhal, P.P.S.; Burian, I.; Ondráček, Jakub; Ždímal, Vladimír; Holub, R.F.

    2017-01-01

    Roč. 175, č. 5 (2017), s. 53-56 ISSN 0144-8420. [Conference on Protection against Radon at Home and at Work / 13th International Workshop on the Geological Aspects of Radon Risk Mapping /8./. Prague, 12.09.2017-16.09.2017] Institutional support: RVO:67985858 Keywords : equilibrium-equivalent concentration * radon * radioactive nenoaerosols Subject RIV: DL - Nuclear Waste, Radioactive Pollution ; Quality OBOR OECD: Environmental sciences (social aspects to be 5.7) Impact factor: 0.917, year: 2016

  17. Organic aerosols

    International Nuclear Information System (INIS)

    Penner, J.E.

    1994-01-01

    Organic aerosols scatter solar radiation. They may also either enhance or decrease concentrations of cloud condensation nuclei. This paper summarizes observed concentrations of aerosols in remote continental and marine locations and provides estimates for the sources of organic aerosol matter. The anthropogenic sources of organic aerosols may be as large as the anthropogenic sources of sulfate aerosols, implying a similar magnitude of direct forcing of climate. The source estimates are highly uncertain and subject to revision in the future. A slow secondary source of organic aerosols of unknown origin may contribute to the observed oceanic concentrations. The role of organic aerosols acting as cloud condensation nuclei (CCN) is described and it is concluded that they may either enhance or decrease the ability of anthropogenic sulfate aerosols to act as CCN

  18. Measurement and analysis of the concentration and size distribution of aerosols in a copper mine

    International Nuclear Information System (INIS)

    Li Dehong; Zhuo Weihai; Huang Gang; Su Xu; Sun Quanfu

    2008-01-01

    Objective: To explore the general characteristics of the concentration and size distribution of aerosols in a mine. Methods: In different areas of a non-uranium mine, the particle number and mass concentration of aerosols were surveyed with a condensation particle counter and a personal aerosol monitor, respectively, and the size distribution of aerosols larger than 1 μm in size was estimated according to the size- selective measurements of mass concentrations. The size distribution of submicron aerosols was evaluated based on the method of screen diffusion battery (SOB), and the measurements were performed in both inside and outside of a control room. Results: The mass concentration of inhaled particles (PM10) was averaged to be 0.42 mg/m 3 in the whole mine, and it varied with different working areas and significantly affected with human activities. In the mine, particles lager than 1 μm in size widely distributed, while the particles less than 5 nm in size were seldom observed. Conclusions: The characteristics of aerosol significantly change with different working areas, human activities and Antilation condition in mine. The dose contribution from inhaled radioactive particles larger than 1 μm in size should be considered in mine. (authors)

  19. Study on the surfactants present in atmospheric aerosols collected in the Okinawa Japan

    Science.gov (United States)

    Kamegawa, A.; Kasaba, T.; Shimabukuro, W.; Arakaki, T.

    2017-12-01

    The main constituent of atmospheric aerosols is organic substances, which occupy 20 to 70% of the mass. Organic matters in the aerosols contain organic acids, protein and humic acid, which behave similar to surfactants. Since surfactants contain both hydrophobic and hydrophilic functional groups in the molecule, they can play important roles in cloud formation and can affect climate change, but detailed mechanisms and magnitude are not well understood. In addition, surfactants can cause asthma, allergy, dry eye and so on. In this study, our aim is to characterize surfactants in the aerosols collected in different seasons in Okinawa, Japan. Atmospheric aerosols were collected at Cape Hedo Atmosphere and Aerosol Monitoring Station (CHAAMS) during Sep. 2013 and July 2014. Surfactants in the environment are comprised of artificially synthesized compounds and naturally derived organics so we only differentiate them into anionic and cationic surfactants. Colorimetric methods were used to determine the concentrations of anionic surfactants as methylene blue active substance (MBAS). Cationic surfactants were also measured by colorimetric method as disulfine blue active substance (DBAS) and showed always below detection limit. Thus, we only discuss anionic surfactants measured as MBAS. Water soluble organic carbon (WSOC) and metal concentrations were also measured for the same aerosol samples. Concentrations of MBAS in the studied samples were 2-3 times higher in spring, fall and winter than those collected in summer. MBAS concentration in the aerosols showed strong correlation with sulfate ion and WSOC, and slightly weaker correlation with nss-sulfate ion. Among the metals, only sodium ion showed a relatively strong correlation with MBAS concentrations. It is suggested that the anionic surfactants in the studied aerosols are mainly derived from marine sources.

  20. Research on aerosol formation, aerosol behaviour, aerosol filtration, aerosol measurement techniques and sodium fires at the Laboratory for Aerosol Physics and Filter Technology at the Nuclear Research Center Karlsruhe

    Energy Technology Data Exchange (ETDEWEB)

    Jordan, S; Schikarski, W; Schoeck, W [Gesellschaft fuer Kernforschung mbH, Karlsruhe (Germany)

    1977-01-01

    The behaviour of aerosols in LMFBR plant systems is of great importance for a number of problems, both normal operational and accident kind. This paper covers the following: aerosol modelling for LMFBR containment systems; aerosol size spectrometry by laser light scattering; experimental facilities and experimental results concerned with aerosol release under accident conditions; filtration of sodium oxide aerosols by multilayer sand bed filters.

  1. Research on aerosol formation, aerosol behaviour, aerosol filtration, aerosol measurement techniques and sodium fires at the Laboratory for Aerosol Physics and Filter Technology at the Nuclear Research Center Karlsruhe

    International Nuclear Information System (INIS)

    Jordan, S.; Schikarski, W.; Schoeck, W.

    1977-01-01

    The behaviour of aerosols in LMFBR plant systems is of great importance for a number of problems, both normal operational and accident kind. This paper covers the following: aerosol modelling for LMFBR containment systems; aerosol size spectrometry by laser light scattering; experimental facilities and experimental results concerned with aerosol release under accident conditions; filtration of sodium oxide aerosols by multilayer sand bed filters

  2. Nuclear Emergency and the Atmospheric Dispersion of Nuclear Aerosols: Discussion of the Shared Nuclear Future - 13163

    International Nuclear Information System (INIS)

    Rana, Mukhtar A.; Ali, Nawab; Akhter, Parveen; Khan, E.U.

    2013-01-01

    This paper has a twofold objective. One is to analyze the current status of high-level nuclear waste disposal along with presentation of practical perspectives about the environmental issues involved. Present disposal designs and concepts are analyzed on a scientific basis and modifications to existing designs are proposed from the perspective of environmental safety. Other is to understand the aerosol formation in the atmosphere for the case of the leakage from the nuclear waste containers or a nuclear accident. Radio-nuclides released from the waste will attach themselves to the existing aerosols in the atmosphere along with formation of new aerosols. Anticipating the nuclear accident when a variety of radioactive aerosols will form and exist in the atmosphere, as a simple example, measurement of naturally existing radioactive aerosols are made in the atmosphere of Islamabad and Murree. A comparison with similar measurements in 3 cities of France is provided. Measurement of radionuclides in the atmosphere, their attachment to aerosols and follow up transport mechanisms are key issues in the nuclear safety. It is studied here how "7Be concentration in the atmospheric air varies in the capital city of Islamabad and a Himalaya foothill city of Murree (Pakistan). Present results are compared with recent related published results to produce a "7Be concentration versus altitude plot up to an altitude of 4000 m (a.s.l.). Origin and variance of "7Be concentration at different altitudes is discussed in detail. The relevance of results presented here with the evaluation of implications of Chernobyl and Fukushima nuclear disasters has been discussed in a conclusive manner. It is the first international report of a joint collaboration/project. The project is being generalized to investigate and formulate a smooth waste storage and disposal policy. The project will address the fission and fusion waste reduction, its storage, its recycling, air, water and soil quality

  3. Nuclear Emergency and the Atmospheric Dispersion of Nuclear Aerosols: Discussion of the Shared Nuclear Future - 13163

    Energy Technology Data Exchange (ETDEWEB)

    Rana, Mukhtar A. [Science-Admin Coherence Cell (SACC), PINSTECH Admin Blk, PAEC, Islamabad (Pakistan); Ali, Nawab [Physics Division, Directorate of Science, Pakistan Institute of Nuclear Science and Technology (PINSTECH), P.O. Nilore, Islamabad (Pakistan); Akhter, Parveen [Pakistan Institute of Engineering and Applied Sciences (PIEAS), Islamabad (Pakistan); Khan, E.U. [Department of Physics, International Islamic University (IIU), Kettle Fields, Kashmir Highways, Islamabad (Pakistan)

    2013-07-01

    This paper has a twofold objective. One is to analyze the current status of high-level nuclear waste disposal along with presentation of practical perspectives about the environmental issues involved. Present disposal designs and concepts are analyzed on a scientific basis and modifications to existing designs are proposed from the perspective of environmental safety. Other is to understand the aerosol formation in the atmosphere for the case of the leakage from the nuclear waste containers or a nuclear accident. Radio-nuclides released from the waste will attach themselves to the existing aerosols in the atmosphere along with formation of new aerosols. Anticipating the nuclear accident when a variety of radioactive aerosols will form and exist in the atmosphere, as a simple example, measurement of naturally existing radioactive aerosols are made in the atmosphere of Islamabad and Murree. A comparison with similar measurements in 3 cities of France is provided. Measurement of radionuclides in the atmosphere, their attachment to aerosols and follow up transport mechanisms are key issues in the nuclear safety. It is studied here how {sup 7}Be concentration in the atmospheric air varies in the capital city of Islamabad and a Himalaya foothill city of Murree (Pakistan). Present results are compared with recent related published results to produce a {sup 7}Be concentration versus altitude plot up to an altitude of 4000 m (a.s.l.). Origin and variance of {sup 7}Be concentration at different altitudes is discussed in detail. The relevance of results presented here with the evaluation of implications of Chernobyl and Fukushima nuclear disasters has been discussed in a conclusive manner. It is the first international report of a joint collaboration/project. The project is being generalized to investigate and formulate a smooth waste storage and disposal policy. The project will address the fission and fusion waste reduction, its storage, its recycling, air, water and soil

  4. Development of aerosol decontamination factor evaluation method for filtered containment venting system

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jae bong; Kim, Sung Il; Jung, Jaehoon; Ha, Kwang Soon; Kim, Hwan Yeol [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2016-10-15

    Fission products would be released from molten corium pools which are relocated into the lower plenum of reactor pressure vessel, on the concrete pit and in the core catcher. In addition, steam, hydrogen and noncondensable gases such as CO and CO2 are generated during the core damage progression due to loss of coolant and the molten core-concrete interaction. Consequently, the pressure inside the containment could be increased continuously. Filtered containment venting is one action to prevent an uncontrolled release of radioactive fission products caused by an overpressure failure of the containment. After the Fukushima-Daiichi accident which was demonstrated the containment failure, many countries to consider the implementation of filtered containment venting system(FCVS) on nuclear power plant where these are not currently applied. In general evaluation for FCVS is conducted to determine decontamination factor on several conditions (aerosol diameter, submergence depth, water temperature, gas flow, steam flow rate, pressure, operating time,...). It is essential to quantify the mass concentration before and after FCVS for decontamination factor. This paper presents the development of the evaluation facility for filtered containment venting system at KAERI and an experimental investigation for aerosol removal performance. Decontamination factor for the FCVS is determined by filter measurement. The result of the aerosol size distribution measurement shows the aerosol removal performance by an aerosol size.

  5. Optimization of the retention of radioactive material from the airborne effluents of reprocessing plants

    International Nuclear Information System (INIS)

    Bonka, H.; Horn, H.-G.

    1984-01-01

    The radiation-protection ordinance of the Federal Republic of Germany does not know the expression 'optimization in radiological protection'. In order to gain experiences with the cost-benefit analysis for the retention of radioactive material from nuclear facilities as proposed in ICRP 26, this method has been applied on the emission of radioactive material with the airborne effluents of reprocessing plants. The reference plant has an annual throughput of 1500 t of spent LWR-fuel. Basing on this plant, two smaller plants (350 t/a, 700 t/a) are also analysed. The cost-benefit-analysis is carried-out for H3, C14, Kr85, J129 and aerosols. For these nuclides as well as for the three plant-sizes, the methods of retention, the estimated annual costs of retention, the emission rates for the different retention measures and the resulting collective-dose commitments are shown. Based on an α-value of 8000 $/man-Sv (20,000 DM/Man-Sv) the cost-benefit analysis shows no optimum for H3 and Kr 85. The optimum C14 as well as iodine retention is a high-efficiency scrubber and an iodine filter, respectively for the dissolver off-gas. For aerosols the cost-benefit analysis shows an optimum for the filtration of the dissolver off-gas by means of HEPA filters. For the other aerosol-sources, condensation, scrubbing and additional droplet separation from the off-gas is optimum. Reasons differing from cost-benefit analysis require HEPA filters for all major aerosol-sources. (author)

  6. Radioactivity in the Rhine - the LWA controls North-Rhine-Westphalian surface waters

    International Nuclear Information System (INIS)

    Kloes, H.

    1985-01-01

    The State Authority for Water and Waste Management has been testing the Rhine and the most important surface waters of North-Rhine Westphalia for radioactivity ever since it was founded in 1969. Radiation exposure of human beings who use Rhine water is far below the permitted maximum values of the 'radiation protection ordinance'. Pollution of the Rhine and its tributaries in North-Rhine Westphalia with artificial radioactive substances has even slightly decreased over the past ten years; pollution of the River Emscher with natural radioactive material remained high, the Lippe River now contains less radium than before. (orig./PW) [de

  7. A first experiment on the scavenging of materials by rainfall using a large artificial climate experiment chamber at ACEF in IES

    International Nuclear Information System (INIS)

    Kawabata, Hitoshi; Hasegawa, Hidenao; Akata, Naofumi; Chikuchi, Yuki; Kondo, Kunio; Inaba, Jiro

    2004-01-01

    Radionuclides in the atmosphere are removed to rough surfaces on the earth through wet or dry removal. According to our past results, the wet deposition flux of sea-salt particles is larger than the dry deposition flux in Rokkasho, Aomori. Therefore, to clarify the mechanism of wet removal of aerosol particles, a laboratory experiment using a large artificial climate experiment chamber at the Artificial Climate Experiment Facility (ACEF) in the Institute for Environmental Sciences was started. We conducted a preliminary experiment on the scavenging of aerosol particles by raindrops. The scavenging coefficient for NaCl particles was larger than that for test powder (JIS Z 8901 No. 11 Kanto loam). The scavenging coefficients for NaCl particles and test powder increased exponentially with the increase of precipitation intensity. (author)

  8. Radioactivity introduction and history, from the quantum to quarks

    CERN Document Server

    L'Annunziata, Michael F

    2016-01-01

    As a comprehensive review of radioactivity from natural and artificial sources on earth and radiation of cosmic origins, this book provides users with a chronological account of the significant historical events on the topic dating from 1895 to the present, along with an introduction to the atom and its nucleus.

  9. Experimental investigation of the role of ions in aerosol nucleation

    DEFF Research Database (Denmark)

    Enghoff, Martin Andreas Bødker

    The role of ions in producing aerosols in Earth’s atmosphere is an area of very active research. Atmospheric and experimental observations have shown that the nucleation of aerosol particles can occur under conditions that cannot be explained by classical nucleation theory. Several ideas have been...... put forward to solve this nucleation problem, e.g. Ion-Induced Nucleation and Ternary Nucleation. Experimental investigations exploring the role of ions in particle production are scarce, and often at conditions far removed from those relevant for the lower part of the atmosphere. Recent experimental...... were grown using photochemically produced sulphuric acid and ionization levels were controlled with a Cs-137 gamma-source. An increase in nucleation was observed when the chamber was exposed to the radioactive source. The results were analyzed using a model based on the General Dynamic Equation...

  10. Determination of the radioactive aerosols transport coefficients generated in open pit uranium mining areas

    International Nuclear Information System (INIS)

    Azevedo Py Junior, D. de.

    1978-01-01

    The classical atmospheric transport model is applied to uranium mining operations. Among the transport parameters there is one concerned with radioactive decay, but it does not include the radioactive decay series which is the specific case for uranium. Therefore, an extension of the transport theory is developed and tested, giving results greater than the ones obtained with the classical model, as expected. (author)

  11. Using the OMI aerosol index and absorption aerosol optical depth to evaluate the NASA MERRA Aerosol Reanalysis

    Science.gov (United States)

    Buchard, V.; da Silva, A. M.; Colarco, P. R.; Darmenov, A.; Randles, C. A.; Govindaraju, R.; Torres, O.; Campbell, J.; Spurr, R.

    2015-05-01

    A radiative transfer interface has been developed to simulate the UV aerosol index (AI) from the NASA Goddard Earth Observing System version 5 (GEOS-5) aerosol assimilated fields. The purpose of this work is to use the AI and aerosol absorption optical depth (AAOD) derived from the Ozone Monitoring Instrument (OMI) measurements as independent validation for the Modern Era Retrospective analysis for Research and Applications Aerosol Reanalysis (MERRAero). MERRAero is based on a version of the GEOS-5 model that is radiatively coupled to the Goddard Chemistry, Aerosol, Radiation, and Transport (GOCART) aerosol module and includes assimilation of aerosol optical depth (AOD) from the Moderate Resolution Imaging Spectroradiometer (MODIS) sensor. Since AI is dependent on aerosol concentration, optical properties and altitude of the aerosol layer, we make use of complementary observations to fully diagnose the model, including AOD from the Multi-angle Imaging SpectroRadiometer (MISR), aerosol retrievals from the AErosol RObotic NETwork (AERONET) and attenuated backscatter coefficients from the Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation (CALIPSO) mission to ascertain potential misplacement of plume height by the model. By sampling dust, biomass burning and pollution events in 2007 we have compared model-produced AI and AAOD with the corresponding OMI products, identifying regions where the model representation of absorbing aerosols was deficient. As a result of this study over the Saharan dust region, we have obtained a new set of dust aerosol optical properties that retains consistency with the MODIS AOD data that were assimilated, while resulting in better agreement with aerosol absorption measurements from OMI. The analysis conducted over the southern African and South American biomass burning regions indicates that revising the spectrally dependent aerosol absorption properties in the near-UV region improves the modeled-observed AI comparisons

  12. Development of an advanced radioactive airborne particle monitoring system for use in early warning networks.

    Science.gov (United States)

    Baeza, A; Corbacho, J A; Caballero, J M; Ontalba, M A; Vasco, J; Valencia, D

    2017-09-25

    Automatic real-time warning networks are essential for the almost immediate detection of anomalous levels of radioactivity in the environment. In the case of Extremadura region (SW Spain), a radiological network (RARE) has been operational in the vicinity of the Almaraz nuclear power plant and in other areas farther away since 1992. There are ten air monitoring stations equipped with Geiger-Müller counters in order to evaluate the external ambient gamma dose rate. Four of these stations have a commercial system that provides estimates of the total artificial alpha and beta activity concentrations in aerosols, and of the 131 I activity (gaseous fraction). Despite experience having demonstrated the benefits and robustness of these commercial systems, important improvements have been made to one of these air monitoring systems. In this paper, the analytical and maintenance shortcomings of the original commercial air monitoring system are described first; the new custom-designed advanced air monitoring system is then presented. This system is based mainly on the incorporation of gamma spectrometry using two scintillation detectors, one of NaI:Tl and the other of LaBr 3 :Ce, and compact multichannel analysers. Next, a comparison made of the results provided by the two systems operating simultaneously at the same location for three months shows the advantages of the new advanced air monitoring system. As a result, the gamma spectrometry analysis allows passing from global alpha and beta activity determinations due to artificial radionuclides in aerosols, and the inaccurate measurement of the gaseous 131 I activity concentration, to the possibility of identifying a large number of radionuclides and quantifying each of their activity concentrations. Moreover, the new station's dual capacity is designed to work in early warning monitoring mode and surveillance monitoring mode. This is based on custom developed software that includes an intelligent system to issue the

  13. Survey monitoring of environmental radioactivity in Daegu area

    International Nuclear Information System (INIS)

    Kang, Hee Dong; Lee, Hae Young; Yang, Chan Sun

    2001-12-01

    The objectives of the project are to monitor an abnormal radiation level in Taegu and Kyungpook region, and to enhance our ability to prepare for the radiological emergency situation by establishing the radioactivity monitoring system in Taegu and Kyungpook region. In this report, we summarized a gamma exposure rates, a gross beta and gamma radionuclide activities for the environmental samples of airborned-dust. precipitation, fallout and tap water collected in Taegu radioactivity monitoring center, and a gamma radionuclide activities for the 28 grocery samples, such as tea, nut and mushroom, rice, chinese cabbage, wormwood and pine needles, soil and drinking water which were obtained from Taegu and Kyungpook region to establish the basic data base for estimating the internal exposure. In conclusion, it didn't appear any evidence for newly pollution of artificial radioactivity in Taegu and Kyungpook region

  14. Evaluation Of Radioactivity Of Released Air During Postirradiation Examination At The RMI

    International Nuclear Information System (INIS)

    Prayitno, B.; Eko, Pudjadi

    1998-01-01

    Radioactivity evaluation of released air during post-irradiation examination at RMI has been done since january 1993 to december 1996. The released air radioactivity has been observed during post-irradiation examinations of irradiated fuels and structure materials in the hot cell. Analysis method employed has been by air sampling and measurement of the alpha and beta activities by using alpha beta aerosol LB 150 D model. Air release from RMI was sucked by using an air pump having 40 m3/hour capacity which is equipped with a 200 mm diameter filter paper. The filter paper is automatically counted by the detector of the instrument. The average of the daily maximum counting result in a month has been used as monthly data. It has been shown that there have been increase in the released air radioactivity caused by the post-irradiation examination activity. The data of the released air activity obtained have been used to calculate the radioactivity concentration and radioactivity on the soil surface based on Gauss Plumes. The calculation result have shown that the alpha and beta radioactivity concentration at stacks and on the soil surface are less then the set maximum permissible concentration (MPC)

  15. Study, assessment of radioactive dose on China's population

    Energy Technology Data Exchange (ETDEWEB)

    Ziqiang, P.

    1984-05-10

    The national population dose is defined as the radioactive dose from both natural and artificial sources which is received by the entire Chinese population. The necessity and prospects for developing ways to assess China's national population dose and some noteworthy problems in this area are described.

  16. Penetration of HEPA filters by alpha recoil aerosols

    International Nuclear Information System (INIS)

    McDowell, W.J.; Seeley, F.G.; Ryan, M.T.

    1976-01-01

    Tests at Oak Ridge National Laboratory confirmed that alpha-emitting particulate matter does penetrate high-efficiency filter medium, identical to that used in HEPA filters, much more effectively than do non-radioactive or beta-gamma active aerosols. Filter retention efficiencies drastically lower than the 99.97 percent quoted for ordinary particulate matter have been observed with 212 Pb, 253 Es, and 238 Pu sources, indicating that the phenomenon is common to all of these and probably to all alpha-emitting materials of appropriate half-life. Results with controlled air-flow through filters in series are consistent with the picture of small particles dislodged from the ''massive'' surface of an alpha-active material, and then repeatedly dislodged from positions on the filter fibers, by the alpha recoils. The process shows only a small dependence on the physical form of the source material. Oxide dust, nitrate salt, and plated metal all seem to generate the recoil particles effectively. The amount penetrating a series of filters depends on the total amount of activity in the source material, its specific activity, and the length of time of air flow. Dependence on the air flow velocity is slight. It appears that this phenomenon has not been observed in previous experiments with alpha-active aerosols because the tests did not continue for a sufficiently long time. A theoretical model of the process has been developed, amenable to computer handling, that should allow calculation of the rate constants associated with the transfer through and release of radioactive material from a filter system by this process

  17. Radioactivity and Nuclear Issues in Science Fiction

    International Nuclear Information System (INIS)

    Franic, Z.

    2008-01-01

    In this work are presented and reviewed science fiction narratives, films and comics that exploit radioactivity and nuclear issues. These topics to some science fiction authors serve as metaphor of evil and holocaust as well as nice instrument for elaborating various manipulations and conspiracy theories. In that context are of special interest science fiction works depicting apocalyptic post-nuclear worlds and societies, such works being closely connected with cyberpunk genre. However, other more technologically optimistic authors nuclear energy and research regarding nuclear technology and radioactivity consider as eligible and inevitable solution for world peace and prosperity Nowadays, public interest and global fears are shifted from radioactivity and nuclear issues to other catastrophic scenarios threatening future of the mankind, these for example being climate changes and global warming, asteroid impact, collapse of information infrastructure, nanotechnology, robotics and artificial intelligence etc. Consequently, these issues are as well increasingly reflected in contemporary science fiction stories.(author)

  18. Literature in focus: The history of radioactivity

    CERN Document Server

    2006-01-01

    René Bimbot, an expert in nuclear physics, will be coming to present his book - The History of Radioactivity. The work provides a summary of our accumulated knowledge of radioactivity and its applications, from its discovery to the present day. Presented in layman's terms, and backed by plenty of illustrations, the work creates the link between the rudimentary knowledge available in the times of Becquerel and the Curies and contemporary physics. It takes us on a great physics adventure, from the nucleus to the quark, from artificial radioactivity to radiotherapy, from the discovery of fission to nuclear reactors, not forgetting dating methods. Finally, the work provides a wealth of practical information on radiation and on matters relating to nuclear waste. A former Research Director at the CNRS, a heavy-ion physicist at the Orsay Nuclear Physics Institute, René Bimbot is no stranger to CERN. At the beginning of the 1980s, he worked on the CERN Synchrocyclotron, before joining the GANIL experiment in 1985...

  19. Physical metrology of aerosols; Metrologie physique des aerosols

    Energy Technology Data Exchange (ETDEWEB)

    Boulaud, D.; Vendel, J. [CEA Saclay, 91 - Gif-sur-Yvette (France). Inst. de Protection et de Surete Nucleaire

    1996-12-31

    The various detection and measuring methods for aerosols are presented, and their selection is related to aerosol characteristics (size range, concentration or mass range), thermo-hydraulic conditions (carrier fluid temperature, pressure and flow rate) and to the measuring system conditions (measuring frequency, data collection speed, cost...). Methods based on aerosol dynamic properties (inertial, diffusional and electrical methods) and aerosol optical properties (localized and integral methods) are described and their performances and applications are compared

  20. Effective dose equivalent to breast fed infants due to artificial and natural radioactivity

    International Nuclear Information System (INIS)

    Campos Venuti, G.; Felici, F.; Grisanti, A.; Grisanti, G.; Risica, S.; Simula, S.

    1988-01-01

    After the Chernobyl accident, the Italian National Institute of Health (ISS), with the collaboration of the Epidemiological Unit of Latium District, started a research devoted to the study of the radioactive contamination of human milk in Latium. The motivation is three-fold, namely: to measure the contamination of a food product utilised for infants in order to assess the corresponding dose to breast-fed infants; to clarify any possible correlations between radioactive levels in human milk and those in the total body; to correlate the levels in human milk with those in the maternal diet

  1. Atmospheric Aerosol Emissions Related to the Mediterranean Seawater Biogeochemistry

    Science.gov (United States)

    Sellegri, K.; Schwier, A.; Rose, C.; Gazeau, F. P. H.; Guieu, C.; D'anna, B.; Ebling, A. M.; Pey, J.; Marchand, N.; Charriere, B.; Sempéré, R.; Mas, S.

    2016-02-01

    Marine aerosols contribute significantly to the global aerosol load and consequently has an important impact on the Earth's climate. Different factors influence the way they are produced at the air/seawater interface. The sea state (whitecap coverage, temperature, etc. ) influence the size and concentration of primarily produced particles but also biogeochemical characteristics of the seawater influence both the physical and chemical primary fluxes to the atmosphere. An additional aerosol source of marine aerosol to the atmosphere is the formation of new particles by gaz-to-particle conversion, i.e. nucleation. How the seawater and surface microlayer biogeochemical compositions influences the aerosol emissions is still a large debate. In order to study marine emissions, one approach is to use semi-controlled environments such as mesocosms. Within the MedSea and SAM projects, we characterize the primary Sea Spray Aerosol (SSA) during mesocosms experiments performed during different seasons in the Mediteranean Sea. Mesocosms were either left unchanged as control or enriched by addition of nutriments in order to create different levels of phytoplanctonic activities. The mesocosms waters were daily analyzed for their chemical and biological composition (DOC, CDOM, TEP, Chl-a, virus, bacteria, phytoplankton and zooplankton concentrations). SSA production by bubble bursting was daily simulated in a dedicated set-up. The size segregated SSA number fluxes, cloud condensation nuclei (CCN) properties, and chemical composition were determined as a function of the seawater characteristics. We show that the SSA organic content was clearly correlated to the seawater Chl-a level, provided that the mesocosm was not enriched to create an artificial phytoplanctonic bloom. In our experiments, the enrichment of the seawater with natural surface microlayer did not impact the SSA organic content nor its CCN properties. At last, nucleation of secondary particles were observed to occur in

  2. Aerial spraying to capture released radioactivity from NPP in a severe accident

    International Nuclear Information System (INIS)

    Younus, Irfan; Yim, Man Sung; Medard, Thiphaine

    2016-01-01

    The proposed strategy in this paper is the use of aqueous spray (water/foam) mixed with suitable chemical additives to capture, dissolve and stabilize the radioactive gases and aerosol particles released from leaked reactor containment and auxiliary building. The spray system can be approached to the leaked reactor building through the use of a truck with high rising cranes, unmanned aerial vehicles (UAVs, such as helicopters), aerostats, or by installing fixed piping structure around the containment building depending on the accident situation. Laboratory-scale experimental system was setup to examine the performance of such systems. The alkaline water (aqueous NaOH.Na_2S_2O_3) and foam-based spray material (sodium lauryl sulphate) were used to examine capture efficiency of gaseous iodine and aerosol particles. The gaseous iodine and aerosol removal efficiency of foam-based spray is higher when compared with alkaline water-based spray. 2. The nozzle producing full cone spray provides the better removal efficiency than nozzle producing hollow cone spray patterns.

  3. Simulations of the observation of clouds and aerosols with the Experimental Lidar in Space Equipment system.

    Science.gov (United States)

    Liu, Z; Voelger, P; Sugimoto, N

    2000-06-20

    We carried out a simulation study for the observation of clouds and aerosols with the Japanese Experimental Lidar in Space Equipment (ELISE), which is a two-wavelength backscatter lidar with three detection channels. The National Space Development Agency of Japan plans to launch the ELISE on the Mission Demonstrate Satellite 2 (MDS-2). In the simulations, the lidar return signals for the ELISE are calculated for an artificial, two-dimensional atmospheric model including different types of clouds and aerosols. The signal detection processes are simulated realistically by inclusion of various sources of noise. The lidar signals that are generated are then used as input for simulations of data analysis with inversion algorithms to investigate retrieval of the optical properties of clouds and aerosols. The results demonstrate that the ELISE can provide global data on the structures and optical properties of clouds and aerosols. We also conducted an analysis of the effects of cloud inhomogeneity on retrievals from averaged lidar profiles. We show that the effects are significant for space lidar observations of optically thick broken clouds.

  4. Radioactivity monitoring status in French Polynesia in 2008. Results from IRSN's monitoring network

    International Nuclear Information System (INIS)

    2009-01-01

    Radiological monitoring of the French environment is one of IRSN's permanent tasks as part of public policy on nuclear safety and radiological protection. It is helping to guarantee the best possible protection of the population. The task addresses two objectives: - To monitor the levels of artificial radioactivity in all sectors of the environment and in major foodstuffs; - To estimate the exposure of the Polynesian population to this artificial radioactivity. The IRSN has monitored radioactivity levels in French Polynesia, excluding the Mururoa and Fangataufa nuclear experimentation centres, since 1962. This task is realized by the IRSN's Environmental Study and Monitoring Laboratory located in Tahiti (Vairao) This monitoring was instigated at the time when atmospheric nuclear weapons testing was being performed by the major powers (the United States, the Soviet Union, the United Kingdom, France and China), causing fallout of artificial radionuclides, over several years, on a planetary scale. In French Polynesia, the IRSN is most particularly interested in fallout resulting from the 41 tests carried out by France in this region of the globe between 1966 and 1974, and in its consequent effects on the population. Today, just as in metropolitan France, the IRSN carries out monitoring as part of its mission to constantly monitor radiological protection factors. The monitoring takes place on seven islands (Tahiti, Maupiti, Hao, Rangiroa, Hiva Oa, Mangareva and Tubuai) representing the five archipelagoes and consists of taking monthly samples of various kinds from the different environmental compartments (air, water, soil, food...) with which the population may be in contact. For more than 40 years, the IRSN takes part in the evaluation of the dosimetric consequences of these atmospheric depositions in French Polynesia. This laboratory is established in Tahiti. The ingestion component of this dosimetric evaluation requires to collect the most representative samples of

  5. Introduction to the problems of the radioactive wastes

    International Nuclear Information System (INIS)

    Barrachina, M.

    1990-01-01

    Small book intended to provide basic information to non-specialists about the nature and the risks of radioactive wastes. The subject is developed through five chapters: Ch. I underlines the idea that the XX Century nuclear reactors and 'artificial' radioactivity to that naturally occurring in the Earth since the last event of the nucleosynthesis of the elements in the Solar System, some 4500 millions of years ago; Ch. II describes the ordered universal set of atomic units (nucleidic chart) responsible for all the kinds of known matter, and their transformation rules by which radioactivity is created. Ch. III explains the properties of radioactive wastes as a result of their radionuclide content; Ch. IV puts into perspective the hazards of this kink of wastes by comparison to other common occurring wastes generated by human activity; and finally; Ch. V refers to the risks of the Earth (as a cosmic repository), in order to provide a natural reference level to assess the risk legacy that we will afford to future generations. (Author)

  6. Study on adsorption behavior of radioiodine gas using incense stick aerosol

    International Nuclear Information System (INIS)

    Murata, Mikio; Noguchi, Hiroshi; Kato, Shohei; Kokubu, Morinobu

    1987-01-01

    Adsorption of radioactive elemental iodine gas ( 131 I 2 ) on incense stick aerosol particles has been studied to provide basic data for a realistic and precise assessment of dose to the public due to radioiodine released from nuclear facilities. A mixture of iodine gas and aerosol was passed once through a glass vessel to cause the adsorption reaction. The adsorption was studied at different reaction times, initial I 2 gas concentrations and particle number concentrations. The results showed that the adsorption reached an equilibrium in about 2 min at the initial I 2 gas concentration of 10 -10 g/cm 3 . The proportion of iodine adsorbed by the aerosol particles was almost constant, about 25 % at the initial I 2 gas concentrations below 10 -11 g/cm 3 and at the reaction time of 1 min, and decreased with increase of the initial concentration over 10 -11 g/cm 3 . The adsorption isotherm of the aerosol for the gas was obtained from the experimental data. The semi-empirical equations to explain the adsorption reaction were also obtained based on the experimental data and the FUCHS's equation relating to vaporization of a droplet. The sticking probability in the equations was estimated to be 7.6 x 10 -3 . The calculated results using the equations were in good agreement with the experimental ones. (author)

  7. Correlation between Asian Dust and Specific Radioactivities of Fission Products Included in Airborne Samples in Tokushima, Shikoku Island, Japan, Due to the Fukushima Nuclear Accident

    International Nuclear Information System (INIS)

    Sakama, M.; Nagano, Y.; Kitade, T.; Shikino, O.; Nakayama, S.

    2014-01-01

    Radioactive fission product 131 I released from the Fukushima Daiichi Nuclear Power Plants (FD-NPP) was first detected on March 23, 2011 in an airborne aerosol sample collected at Tokushima, Shikoku Island, located in western Japan. Two other radioactive fission products, 134 Cs and 137 Cs were also observed in a sample collected from April 2 to 4, 2011. The maximum specific radioactivities observed in this work were about 2.5 to 3.5 mBq×m -3 in a airborne aerosol sample collected on April 6. During the course of the continuous monitoring, we also made our first observation of seasonal Asian Dust and those fission products associated with the FDNPP accident concurrently from May 2 to 5, 2011. We found that the specific radioactivities of 134 Cs and 137 Cs decreased drastically only during the period of Asian Dust. And also, it was found that this trend was very similar to the atmospheric elemental concentration (ng×m -3 ) variation of stable cesium ( 133 Cs) quantified by elemental analyses using our developed ICP-DRC-MS instrument

  8. Natural radioactivity in iron and steel materials by low-level gamma spectrometry

    International Nuclear Information System (INIS)

    Tanase, G.; Tanase, Maria

    2003-01-01

    High resolution low-level gamma spectrometry was applied to perform a radioactivity measurement in iron and steel raw materials (coal, coke, iron ore, pellets, manganese ore, limestone, dolomite), auxiliary materials (scorialite, oxide of Ti, bentonite), and some related final products (cast iron, slag, blast-furnace, flue dust) involved in iron making processing. We control the activity of materials in various kinds of samples and we investigate for transfer of radioactivity during the blast-furnace process. Artificial radioisotopes are rarely encountered. (authors)

  9. The Effect of Aerosol Hygroscopicity and Volatility on Aerosol Optical Properties During Southern Oxidant and Aerosol Study

    Science.gov (United States)

    Khlystov, A.; Grieshop, A. P.; Saha, P.; Subramanian, R.

    2014-12-01

    Secondary organic aerosol (SOA) from biogenic sources can influence optical properties of ambient aerosol by altering its hygroscopicity and contributing to light absorption directly via formation of brown carbon and indirectly by enhancing light absorption by black carbon ("lensing effect"). The magnitude of these effects remains highly uncertain. A set of state-of-the-art instruments was deployed at the SEARCH site near Centerville, AL during the Southern Oxidant and Aerosol Study (SOAS) campaign in summer 2013 to measure the effect of relative humidity and temperature on aerosol size distribution, composition and optical properties. Light scattering and absorption by temperature- and humidity-conditioned aerosols was measured using three photo-acoustic extinctiometers (PAX) at three wavelengths (405 nm, 532 nm, and 870 nm). The sample-conditioning system provided measurements at ambient RH, 10%RH ("dry"), 85%RH ("wet"), and 200 C ("TD"). In parallel to these measurements, a long residence time temperature-stepping thermodenuder (TD) and a variable residence time constant temperature TD in combination with three SMPS systems and an Aerosol Chemical Speciation Monitor (ACSM) were used to assess aerosol volatility and kinetics of aerosol evaporation. We will present results of the on-going analysis of the collected data set. We will show that both temperature and relative humidity have a strong effect on aerosol optical properties. SOA appears to increase aerosol light absorption by about 10%. TD measurements suggest that aerosol equilibrated fairly quickly, within 2 s. Evaporation varied substantially with ambient aerosol loading and composition and meteorology.

  10. Environmental radioactivity and radiation exposure

    International Nuclear Information System (INIS)

    1976-01-01

    The environmental radioactivity in the Federal Republic of Germany was almost as high in 1976 as in 1975. It only increased temporarily in autumn 1976 as a result of the above-ground nuclear weapons test of the People's Republic of China on September 29th 1976 and then returned to its previous level. The radioactivity in food had a slight decreasing trend in 1976, apart from a temporary increase in the radioactivity in milk also caused by the nuclear weapons test mentioned. The population exposure remains basically unchanged in 1976 compared with 1975. The artificial radiation exposure is about half as high as the natural radiation exposure to which man has always been exposed. The former is based to 83% on using X-rays in medicine, particularly for X-ray diagnostic purposes. The population exposure due to nuclear power plants and other nuclear plants is still well below 1% of the natural radiation exposure although in 1976 three new nuclear power plants were put into operation. This is also true for the average radiation exposure within an area of 3 km around the nuclear plant. (orig.) [de

  11. Proceedings of the workshop on radioactivity associated with coal use

    International Nuclear Information System (INIS)

    1981-12-01

    A workshop on radioactivity in coal use was held on September 15 through 17, 1981, under the auspices of the US Department of Energy, Office of Environmental Programs, and the Los Alamos National Laboratory. The purpose of the workshop was to identify research issues associated with radioactivity resulting from the use of coal for electric power generation. The concensus of the 10 scientists participating in the workshop was that a moderate to strong need exists for research in solubility of fly ash in different fluids and for determination of radioactivity in construction materials. Several additional research issues were identified but were given a lower priority. Summaries of each presentation are included. Titles are: some effects of coal combustion on the radiation environment; radionuclides in western coal at Mound; low-level radiation in coals utilized and ashes produced at New York State electric utilities; radioactivity from coal use - where are the problems; chemistry of radionuclides in coal preparation; uranium daughters in natural atmospheric aerosols and coal-fired power plant emissions; possible contributions of coal extraction and utilization to radioactivity contributions in drinking water; and impact on water quality from radionuclides in coal. One paper has been abstracted separately for inclusion in the Energy Data Base

  12. Airborne anthropogenic radioactivity measurements from an international radionuclide monitoring system

    International Nuclear Information System (INIS)

    Mason, L.R.; Bohner, J.D.; Williams, D.L.

    1998-01-01

    Anthropogenic radioactivity is being measured in near-real time by an international monitoring system designed to verify the Comprehensive Nuclear Test Ban Treaty. Airborne radioactivity measurements are conducted in-situ by stations that are linked to a central data processing and analysis facility. Aerosols are separated by high-volume air sampling with high-efficiency particulate filters. Radio-xenon is separated from other gases through cryogenic methods. Gamma-spectrometry is performed by high purity germanium detectors and the raw spectral data is immediately transmitted to the central facility via Internet, satellite, or modem. These highly sensitive sensors, combined with the automated data processing at the central facility, result in a system capable of measuring environmental radioactivity on the microbecquerel scale where the data is available to scientists within minutes of the field measurement. During the past year, anthropogenic radioactivity has been measured at approximately half of the stations in the current network. Sources of these measured radionuclides include nuclear power plant emissions, Chernobyl resuspension, and isotope production facilities. The ability to thoroughly characterize site-specific radionuclides, which contribute to the radioactivity of the ambient environment, will be necessary to reduce the number of false positive events. This is especially true of anthropogenic radionuclides that could lead to ambiguous analysis. (author)

  13. Sources and levels of radioactivity in the Philippine environment

    International Nuclear Information System (INIS)

    Duran, E.B.; De Vera, C.M.; De la Cruz, F.M.; Enriquez, E.B.; Garcia, T.Y.; Palad, L.H.; Enriquez, S.O.; Eduardo, J.M.; Asada, A.A.

    1996-01-01

    Over the years, the Health Physics Research Section has assessed the sources and levels of radiation exposure in the Philippine environment. The data show that although Filipinos are exposed to both natural and artificial sources of environmental radioactivity, natural sources contribute much more significantly to the dose received by Filipinos than artificial sources. The average equivalent dose rate due to external sources of natural radiation in the Philippines is 45 μSv h -1 . Of this total dose rate, an average of 22 μSv h -1 is due to cosmic radiation while an average of 23 μSv h -1 is due to terrestrial radiation. External sources of natural radiation in the Philippines thus account for an annual per caput effective dose of about 400 μSv. In contrast, the annual per caput dose due to an artificial source, i.e., nuclear power production, was estimated by UNSCEAR (1988) to be only 0.6 μSv. Based on levels of background radioactivity due to external sources of natural radiation which were measured in 1600 locations, a radiation map of the country was developed. Among the internal sources of natural radiation, radon is the large contributor to dose and is considered as a serious indoor pollutant. Indoor radon levels in about 400 Filipino houses ranged from 1 to 63 Bq m -3 with a mean of 24 Bq m -3 . Significantly higher levels ranging from 30 to 347 Bq m -3 were observed in underground, non-uranium mines. Since there are no operational nuclear power plant in the Philippines, artificial radionuclides in the environment consist mainly of long-lived 137 Cs and 90 Sr from atmospheric nuclear weapons tests

  14. Key findings from the artist project on aerosol retention in a dry steam generator

    International Nuclear Information System (INIS)

    Dehbi, Abedeloahab; Suckow, Deltef; Lind, Tettaliisa; Guentat, Salih; Danner, Steffen; Mukin, Roman

    2016-01-01

    A steam generator tube rupture (SGTR) event with a stuck-open safety relief valve constitutes one of the most serious accident sequences in pressurized water reactors (PWRs) because it may create an open path for radioactive aerosol release into the environment. The release may be mitigated by the deposition of fission product particles on a steam generator's (SG's) dry tubes and structures or by scrubbing in the secondary coolant. However, the absence of empirical data, the complexity of the geometry, and the controlling processes have, until recently, made any quantification of retention difficult to justify. As a result, past risk assessment studies typically took little or no credit for aerosol retention in SGTR sequences. To provide these missing data, the Paul Scherrer Institute (PSI) initiated the Aerosol Trapping In Steam GeneraTor (ARTIST) Project, which aimed to thoroughly investigate various aspects of aerosol removal in the secondary side of a breached steam generator. Between 2003 and 2011, the PSI has led the ARTIST Project, which involved intense collaboration between nearly 20 international partners. This summary paper presents key findings of experimental and analytical work conducted at the PSI within the ARTIST program

  15. Key findings from the artist project on aerosol retention in a dry steam generator

    Energy Technology Data Exchange (ETDEWEB)

    Dehbi, Abedeloahab; Suckow, Deltef; Lind, Tettaliisa; Guentat, Salih; Danner, Steffen; Mukin, Roman [Nuclear Energy and Safety Research Department, Paul Scherrer Institute, Villigen (Switzerland)

    2016-08-15

    A steam generator tube rupture (SGTR) event with a stuck-open safety relief valve constitutes one of the most serious accident sequences in pressurized water reactors (PWRs) because it may create an open path for radioactive aerosol release into the environment. The release may be mitigated by the deposition of fission product particles on a steam generator's (SG's) dry tubes and structures or by scrubbing in the secondary coolant. However, the absence of empirical data, the complexity of the geometry, and the controlling processes have, until recently, made any quantification of retention difficult to justify. As a result, past risk assessment studies typically took little or no credit for aerosol retention in SGTR sequences. To provide these missing data, the Paul Scherrer Institute (PSI) initiated the Aerosol Trapping In Steam GeneraTor (ARTIST) Project, which aimed to thoroughly investigate various aspects of aerosol removal in the secondary side of a breached steam generator. Between 2003 and 2011, the PSI has led the ARTIST Project, which involved intense collaboration between nearly 20 international partners. This summary paper presents key findings of experimental and analytical work conducted at the PSI within the ARTIST program.

  16. Key Findings from the Artist Project on Aerosol Retention in a Dry Steam Generator

    Directory of Open Access Journals (Sweden)

    Abdelouahab Dehbi

    2016-08-01

    Full Text Available A steam generator tube rupture (SGTR event with a stuck-open safety relief valve constitutes one of the most serious accident sequences in pressurized water reactors (PWRs because it may create an open path for radioactive aerosol release into the environment. The release may be mitigated by the deposition of fission product particles on a steam generator's (SG's dry tubes and structures or by scrubbing in the secondary coolant. However, the absence of empirical data, the complexity of the geometry, and the controlling processes have, until recently, made any quantification of retention difficult to justify. As a result, past risk assessment studies typically took little or no credit for aerosol retention in SGTR sequences. To provide these missing data, the Paul Scherrer Institute (PSI initiated the Aerosol Trapping In Steam GeneraTor (ARTIST Project, which aimed to thoroughly investigate various aspects of aerosol removal in the secondary side of a breached steam generator. Between 2003 and 2011, the PSI has led the ARTIST Project, which involved intense collaboration between nearly 20 international partners. This summary paper presents key findings of experimental and analytical work conducted at the PSI within the ARTIST program.

  17. Changing transport processes in the stratosphere by radiative heating of sulfate aerosols

    Directory of Open Access Journals (Sweden)

    U. Niemeier

    2017-12-01

    Full Text Available The injection of sulfur dioxide (SO2 into the stratosphere to form an artificial stratospheric aerosol layer is discussed as an option for solar radiation management. Sulfate aerosol scatters solar radiation and absorbs infrared radiation, which warms the stratospheric sulfur layer. Simulations with the general circulation model ECHAM5-HAM, including aerosol microphysics, show consequences of this warming, including changes of the quasi-biennial oscillation (QBO in the tropics. The QBO slows down after an injection of 4 Tg(S yr−1 and completely shuts down after an injection of 8 Tg(S yr−1. Transport of species in the tropics and sub-tropics depends on the phase of the QBO. Consequently, the heated aerosol layer not only impacts the oscillation of the QBO but also the meridional transport of the sulfate aerosols. The stronger the injection, the stronger the heating and the simulated impact on the QBO and equatorial wind systems. With increasing injection rate the velocity of the equatorial jet streams increases, and the less sulfate is transported out of the tropics. This reduces the global distribution of sulfate and decreases the radiative forcing efficiency of the aerosol layer by 10 to 14 % compared to simulations with low vertical resolution and without generated QBO. Increasing the height of the injection increases the radiative forcing only for injection rates below 10 Tg(S yr−1 (8–18 %, a much smaller value than the 50 % calculated previously. Stronger injection rates at higher levels even result in smaller forcing than the injections at lower levels.

  18. Stratospheric aerosols

    International Nuclear Information System (INIS)

    Rosen, J.; Ivanov, V.A.

    1993-01-01

    Stratospheric aerosol measurements can provide both spatial and temporal data of sufficient resolution to be of use in climate models. Relatively recent results from a wide range of instrument techniques for measuring stratospheric aerosol parameters are described. Such techniques include impactor sampling, lidar system sensing, filter sampling, photoelectric particle counting, satellite extinction-sensing using the sun as a source, and optical depth probing, at sites mainly removed from tropospheric aerosol sources. Some of these techniques have also had correlative and intercomparison studies. The main methods for determining the vertical profiles of stratospheric aerosols are outlined: lidar extinction measurements from satellites; impactor measurements from balloons and aircraft; and photoelectric particle counter measurements from balloons, aircraft, and rockets. The conversion of the lidar backscatter to stratospheric aerosol mass loading is referred to. Absolute measurements of total solar extinction from satellite orbits can be used to extract the aerosol extinction, and several examples of vertical profiles of extinction obtained with the SAGE satellite are given. Stratospheric mass loading can be inferred from extinction using approximate linear relationships but under restrictive conditions. Impactor sampling is essentially the only method in which the physical nature of the stratospheric aerosol is observed visually. Vertical profiles of stratospheric aerosol number concentration using impactor data are presented. Typical profiles using a dual-size-range photoelectric dustsonde particle counter are given for volcanically disturbed and inactive periods. Some measurements of the global distribution of stratospheric aerosols are also presented. Volatility measurements are described, indicating that stratospheric aerosols are composed primarily of about 75% sulfuric acid and 25% water

  19. Evaluation on radioactive level and quality of aquatic environment in Suzhou

    International Nuclear Information System (INIS)

    Yu Rongsheng; Tu Yu; Zhang Ruiju

    2007-01-01

    Objective: To assess the quality grade of water source in Suzhou in terms of the radioactive level. Methods: The levels of total α and total β activities in samples of water were detected by relative measurement with medium thickness using model BH 1216 low level α and β detector. 241 Am and pure potassium chloride were used as reference radioactive sources. Results: Among all samples collected, the measured levels varied from (2.62 ± 0.17) x 10 -2 to (8.48±2.80) x 10 -2 Bq/L for total α and (0.77 ± 0.47) x 10 -1 to (3.75 ± 0.26) x 10 -1 Bq/L for total β, the average levels of β/α were from 1.6 to 7.2. Conclusions: The radioactivity level of water source in Suzhou was within the natural background range, free from contamination of artificial radioactive nuclides, which was regarded as good in quality in terms of radioactive level. It is shown that the radioactivity of well water was highest among all investigated water sources. (authors)

  20. A Study on the Design of Novel Neutron Absorber Using Artificial Rare Earth Compound

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Song Hyun; Shin, Chang Ho; Lee, Seung Hyun; Park, Jeia; Kim, Jong Kyung [Hanyang Univ., Seoul (Korea, Republic of); Kim, Soon Young [RADCORE Co., Ltd., Daejeon (Korea, Republic of); Park, Hwan Seo [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2013-10-15

    The artificial rare earth compounds (RE{sub 2}O{sub 3}) generated by the result of the pyro-processing are radioactive wastes which have many long-live radionuclides. Due to the high and long-lived radioactivity of the article RE{sub 2}O{sub 3}, specific radiation shielding and disposal techniques are required. In this study, a simultaneous disposal method of the RE{sub 2}O{sub 3} with the spent fuels is proposed by reusing them for the neutron absorber. In this study, the neutron absorber based on artificial RE{sub 2}O{sub 3} compound was designed for the use in the spent fuel storage. The design of the storage racks for the WH 17Χ17 and PLUS7 spent fuel assemblies were designed and the criticalities were evaluated with the various RE{sub 2}O{sub 3} compositions. Also, the radioactivity and irradiation calculations were performed for the applicability and stability analyses of the neutron absorber into the spent fuel storage. The results show that the neutron absorber can sufficiently reduce the criticality under the regulation guideline. It is expected that the neutron absorber can contribute minimizing the disposal area of the radioactive wastes as well as the reducing the costs and resources for the using the other types of the neutron absorbers.

  1. Long-lived radioactive waste and nuclear plant decommissioning a legacy to future generations

    International Nuclear Information System (INIS)

    McAulay, I.R.

    1996-01-01

    Radioactive waste is an inevitable by-product of all uses of radioactive substances. This is the case of natural radioactivity as well as for artificially produced radioactive isotopes, and it is easy to overlook the significance of the waste problem in the case of technologically enhanced natural radioactivity. Several options are available for the disposal of radioactive waste and the paper considers these in detail from the point of view of the possible future impact of radiation doses to individuals or populations. Particular consideration is given to the use of deep disposal at stable geological sites as a means of dealing with large amounts of radioactive waste. It should not be forgotten that some of what we term waste today need not necessarily always be so. Indeed, there is a good case to make for the recycling of low activity materials rather than the uneconomic expedient of burying them. The paper will consider the possible recycling of valuable materials following suitable reprocessing and dilution and mention the dose implications of examples of such re-utilisation of radioactive materials

  2. Long-lived radioactive waste and nuclear plant decommissioning a legacy to future generations

    Energy Technology Data Exchange (ETDEWEB)

    McAulay, I R [Trinity Coll., Dublin (Ireland). Physical Lab.

    1996-10-01

    Radioactive waste is an inevitable by-product of all uses of radioactive substances. This is the case of natural radioactivity as well as for artificially produced radioactive isotopes, and it is easy to overlook the significance of the waste problem in the case of technologically enhanced natural radioactivity. Several options are available for the disposal of radioactive waste and the paper considers these in detail from the point of view of the possible future impact of radiation doses to individuals or populations. Particular consideration is given to the use of deep disposal at stable geological sites as a means of dealing with large amounts of radioactive waste. It should not be forgotten that some of what we term waste today need not necessarily always be so. Indeed, there is a good case to make for the recycling of low activity materials rather than the uneconomic expedient of burying them. The paper will consider the possible recycling of valuable materials following suitable reprocessing and dilution and mention the dose implications of examples of such re-utilisation of radioactive materials.

  3. 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.

  4. Environmental radioactivity surveillance programme 1999 and 2000

    International Nuclear Information System (INIS)

    Ryan, T.P.; Sequeira, S.; Smith, V.

    2002-02-01

    The Radiological Protection Institute of Ireland continued to monitor levels of radioactivity in air, drinking water and foodstuffs in 1999 and 2000 and the results are presented in this report, the sixth in a series dealing with the terrestrial environment. Radioactivity is present in the terrestrial environment due to natural processes, the testing of nuclear weapons in the atmosphere, accidents such as the Chernobyl accident and the routine discharge of radionuclides from nuclear installations. The Institute monitored airborne radioactivity at ten stations throughout the country. One site was equipped to detect the presence of krypton-85, a radionuclide which is released into the environment primarily as a result of the reprocessing of nuclear fuel at installations such as Sellafield in the UK and La Hague in France. Both in 1999 and 2000, levels of radionuclides in airborne particulates were low and consistent with measurements in previous years. Public water supplies are sampled from each county at least every four years with supplies to certain major population centres sampled annually. Water supplies from eleven counties were sampled between 1999 and 2000 and all of the waters tested were found to be within legal requirements for water quality from a radiological point of view. The levels of artificial radioactivity in milk and other foodstuffs such as milk products, baby foods, beef, lamb, poultry and vegetables continued to be very low in 1999 and 2000 and, for the majority of samples, below the detection limits. External gamma dose rates were monitored continuously at twelve locations around the country. The dose rate was recorded every twenty minutes and the readings transmitted automatically to the Institute's computer database at Clonskeagh (Dublin). No abnormally high levels were observed at any of the twelve stations in either 1999 or 2000. The data presented in this report demonstrate that the levels of artificial radioactivity in the Irish

  5. Environmental radioactivity surveillance programme. 1999 and 2000

    International Nuclear Information System (INIS)

    Ryan, T.; Sequeira, S.; Smith, V.

    2002-02-01

    The Radiological Protection Institute of Ireland continued to monitor levels of radioactivity in air, drinking water and foodstuffs in 1999 and 2000 and the results are presented in this report, the sixth in a series dealing with the terrestrial environment. Radioactivity is present in the terrestrial environment due to natural processes, the testing of nuclear weapons in the atmosphere, accidents such as the Chernobyl accident and the routine discharge of radionuclides from nuclear installations. The Institute monitored airborne radioactivity at ten stations throughout the country. One site was equipped to detect the presence of krypton-85, a radionuclide which is released into the environment primarily as a result of the reprocessing of nuclear fuel at installations such as Sellafield in the UK and La Hague in France. Both in 1999 and 2000, levels of radionuclides in airborne particulates were low and consistent with measurements in previous years. Public water supplies are sampled from each county at least every four years with supplies to certain major population centres sampled annually. Water supplies from eleven counties were sampled between 1999 and 2000 and all of the waters tested were found to be within legal requirements for water quality from a radiological point of view. The levels of artificial radioactivity in milk and other foodstuffs such as milk products, baby foods, beef, lamb, poultry and vegetables continued to be very low in 1999 and 2000 and, for the majority of samples, below the detection limits. External gamma dose rates were monitored continuously at twelve locations around the country. The dose rate was recorded every twenty minutes and the readings transmitted automatically to the Institute's computer database at Clonskeagh (Dublin). No abnormally high levels were observed at any of the twelve stations in either 1999 or 2000. The data presented in this report demonstrate that the levels of artificial radioactivity in the Irish

  6. Ingress of radioactive material into dwellings

    International Nuclear Information System (INIS)

    Roed, J.; Goddard, A.J.H.

    1991-01-01

    People inside buildings will normally obtain some protection against airborne pollution originating in the outdoor air. This protection will be due to deposition indoors on floors, walls, ceilings and furniture, and to filtration during ingress, in cracks, crevices and pores in the building structure. A building will also give some protection against direct gamma radiation from outdoor deposits on the ground and external building surfaces. However, indoor deposits, while reducing air exposure, may add to the dose commitment from direct gamma radiation. Other subsidiary factors such as mechanical transport may need to be considered. We used test houses for finding factors by which outdoor air concentrations exceed those found indoors. Be-7 of cosmogenic origin and associated with natural aerosol has been used as a tracer, together with radionuclides dispersed in the atmosphere as a result of the Chernobyl accident. In addition, SF 6 tracer measurements have been used to measure air exchange rates. Novel experimental arrangements, to isolate the deposition process, were used. Attention has also been given to developing suitable tracers for monodisperse artificial aerosols and to means of detecting such aerosols. The use of these techniques in studying mechanical transport of particulate material is described. The indoor to outdoor airborne concentration ratios in a test house during the Chernobyl accident were found to be 0.25 for caesium, 0.4 for particulate iodine and 0.5 for beryllium-7. Indoor deposition velocities, for a range of radionuclides, ranged from 7 10-5 to 2 10-4 m s-1. Subsequently, aerosol deposition measurements were conducted in unfurnished, partly furnished and fully furnished houses, using Be-7 as a tracer. Measured deposition velocities ranged from 10-5 m s-1 for the unfurnished room to 3 10-5 m s-1 for the fully furnished room

  7. Measurements of radioactive and xenobiotic substances in the biological environment in the Netherlands 1986

    International Nuclear Information System (INIS)

    1988-01-01

    A brief survey of the results of detailed radioactivity measurements performed in the Netherlands during the period immediately after the Chernobylsk accident, and the risk analyses made on the basis of these results, are presented. The increase of the airborne radioactivity and the activity concentrations in surface water during the first week of May 1986 is demonstrated graphically. The radiation dose in 1986 due to artificial radioactivity has been calculated to be about 60 μSv for adults, 70 μSv for ten-year-old children and 110 μSv for one-year-old children. 54 figs.; 32 tabs

  8. Effects of food processing on the radioactivity of vegetables and cereals

    International Nuclear Information System (INIS)

    Roussel-Debet, S.; Real, J.

    1995-01-01

    The decrease of radioactivity for 134 Cs, 85 Sr, 106 Ru, 57 Co, 110m Ag during food processing was measured. Washing and bleaching vegetables directly contaminated by a single aerosol deposit led to a radioactivity decrease (depending on the vegetable, the radionuclide and the time of deposition) up to 90% for caesium. The efficiency of these processes was less important when the vegetables were contaminated by root transfer, except for peeling of root vegetables. Canning of vegetables indirectly contaminated by caesium, strontium, cobalt and ruthenium, after paring and bleaching, was rather interesting with residual radioactivity varying from 30 to 50% for green beans and from 5 to 20% for carrots. Measurements of stable caesium and strontium in cereals before and after industrial processing showed an important activity decrease; retention factors varied from 0.1 to 0.2 for wheat milling and 0.1 to 0.4 for rice processing. (authors). 6 refs., 9 tabs., 1 figs

  9. Evaluation of induced radioactivity in 10 MeV-Electron irradiated spices, (2)

    International Nuclear Information System (INIS)

    Katayama, Tadashi; Furuta, Masakazu; Shibata, Setsuko; Matsunami, Tadao; Ito, Norio; Mizohata, Akira; Toratani, Hirokazu; Takeda, Atsuhiko.

    1994-01-01

    In order to check radioactivity of beta-emmitters produced by (γ, n) reactions which could occur at energies up to 10 MeV, black pepper, white pepper, red pepper, ginger and turmeric were irradiated with 10 MeV electron from a linear accelerator to a dose of 100 kGy. Beta-rays were counted using a 2π gas flow counter and a liquid scintillation counter. Any induced radioactivity could not be detected in irradiated samples. When inorganic compounds containing the nuclides in the list were artificially added in the samples and were irradiated, the β-activities were detected. From the amount of observed radioactivities of β-emmitters produced in the compounds as photonuclear products, it is concluded that the induced radioactivity in natural samples by 10 MeV-electron irradiation were far smaller than natural radioactivity from 40 K contained in the samples and, hence, its biological effects should be negligible. (author)

  10. Tropospheric Aerosols

    Science.gov (United States)

    Buseck, P. R.; Schwartz, S. E.

    2003-12-01

    It is widely believed that "On a clear day you can see forever," as proclaimed in the 1965 Broadway musical of the same name. While an admittedly beautiful thought, we all know that this concept is only figurative. Aside from Earth's curvature and Rayleigh scattering by air molecules, aerosols - colloidal suspensions of solid or liquid particles in a gas - limit our vision. Even on the clearest day, there are billions of aerosol particles per cubic meter of air.Atmospheric aerosols are commonly referred to as smoke, dust, haze, and smog, terms that are loosely reflective of their origin and composition. Aerosol particles have arisen naturally for eons from sea spray, volcanic emissions, wind entrainment of mineral dust, wildfires, and gas-to-particle conversion of hydrocarbons from plants and dimethylsulfide from the oceans. However, over the industrial period, the natural background aerosol has been greatly augmented by anthropogenic contributions, i.e., those produced by human activities. One manifestation of this impact is reduced visibility (Figure 1). Thus, perhaps more than in other realms of geochemistry, when considering the composition of the troposphere one must consider the effects of these activities. The atmosphere has become a reservoir for vast quantities of anthropogenic emissions that exert important perturbations on it and on the planetary ecosystem in general. Consequently, much recent research focuses on the effects of human activities on the atmosphere and, through them, on the environment and Earth's climate. For these reasons consideration of the geochemistry of the atmosphere, and of atmospheric aerosols in particular, must include the effects of human activities. (201K)Figure 1. Impairment of visibility by aerosols. Photographs at Yosemite National Park, California, USA. (a) Low aerosol concentration (particulate matter of aerodynamic diameter less than 2.5 μm, PM2.5=0.3 μg m-3; particulate matter of aerodynamic diameter less than 10

  11. Black carbon aerosol mixing state, organic aerosols and aerosol optical properties over the UK

    Science.gov (United States)

    McMeeking, G. R.; Morgan, W. T.; Flynn, M.; Highwood, E. J.; Turnbull, K.; Haywood, J.; Coe, H.

    2011-05-01

    Black carbon (BC) aerosols absorb sunlight thereby leading to a positive radiative forcing and a warming of climate and can also impact human health through their impact on the respiratory system. The state of mixing of BC with other aerosol species, particularly the degree of internal/external mixing, has been highlighted as a major uncertainty in assessing its radiative forcing and hence its climate impact, but few in situ observations of mixing state exist. We present airborne single particle soot photometer (SP2) measurements of refractory BC (rBC) mass concentrations and mixing state coupled with aerosol composition and optical properties measured in urban plumes and regional pollution over the UK. All data were obtained using instrumentation flown on the UK's BAe-146-301 large Atmospheric Research Aircraft (ARA) operated by the Facility for Airborne Atmospheric Measurements (FAAM). We measured sub-micron aerosol composition using an aerosol mass spectrometer (AMS) and used positive matrix factorization to separate hydrocarbon-like (HOA) and oxygenated organic aerosols (OOA). We found a higher number fraction of thickly coated rBC particles in air masses with large OOA relative to HOA, higher ozone-to-nitrogen oxides (NOx) ratios and large concentrations of total sub-micron aerosol mass relative to rBC mass concentrations. The more ozone- and OOA-rich air masses were associated with transport from continental Europe, while plumes from UK cities had higher HOA and NOx and fewer thickly coated rBC particles. We did not observe any significant change in the rBC mass absorption efficiency calculated from rBC mass and light absorption coefficients measured by a particle soot absorption photometer despite observing significant changes in aerosol composition and rBC mixing state. The contributions of light scattering and absorption to total extinction (quantified by the single scattering albedo; SSA) did change for different air masses, with lower SSA observed in

  12. Measurement of natural and {sup 137}Cs radioactivity concentrations at Izmit Bay (Marmara Sea), Turkey

    Energy Technology Data Exchange (ETDEWEB)

    Öksüz, İ., E-mail: ibrahim-ksz@yahoo.com; Güray, R. T., E-mail: tguray@kocaeli.edu.tr; Özkan, N., E-mail: nozkan@kocaeli.edu.tr; Yalçin, C., E-mail: caner.yalcin@kocaeli.edu.tr [Kocaeli University, Department of Physics, Umuttepe 41380, Kocaeli (Turkey); Ergül, H. A., E-mail: halim.ergul@kocaeli.edu.tr; Aksan, S., E-mail: serdar.aksan@kocaeli.edu.tr [Kocaeli University, Department of Biology, Umuttepe 41380, Kocaeli (Turkey)

    2016-03-25

    In order to determine the radioactivity level at Izmit Bay Marmara Sea, marine sediment samples were collected from five different locations. The radioactivity concentrations of naturally occurring {sup 238}U, {sup 232}Th and {sup 40}K isotopes and also that of an artificial isotope {sup 137}Cs were measured by using gamma-ray spectroscopy. Preliminary results show that the radioactivity concentrations of {sup 238}U and {sup 232}Th isotopes are lower than the average worldwide values while the radioactivity concentrations of the {sup 40}K are higher than the average worldwide value. A small amount of {sup 137}Cs contamination, which might be caused by the Chernobyl accident, was also detected.

  13. The major regularities of the air radioactive contamination of Belarus territory after the Chernobyl accident

    International Nuclear Information System (INIS)

    Konoplya, E. F.; Mironov, V. P.; Drugachenok, M. A.; Kudryashov, V.P; Grushevich, L.E; Adamovich, A.A.

    2001-01-01

    In the first days after the Chernobyl accident the radioactivity of surface air in different regions of Belarus has increased in tens and hundred thousand time. The regular control of air radioactive contamination in the zone of alienation and nearest to it is carried out from the end 1989. The radioactive air monitoring carried out in territories with various contamination density (from 0,2 up to 9,6 MBq/m 2 on Cs-137). The measurements of the Cs-137 contents in ashes of air sampler filters were carried out by gamma - spectrometer ADCAM-300 MCA. The measurement of the Pu-240,239 and Sr-90 contents was carried out by usual radiochemical techniques. The used techniques and equipment allow to define in a sample of the minimal activity: Pu-239,240 - 0,001 Bq, Cs-137 - 0,5 Bq, Sr-90 - 0,1 Bq. The initial contamination of ground happened a near zone within approximately first 2 weeks after accident. Since the end of May, 1986 till present time the air radioactive contamination is formed under action of processes of secondary wind rise and carry of radioactive particles with contaminated territories, which depends from a number factors of both natural and anthropogenous origin. The relations of Pu-238/Pu-239 and Sr-90/Pu-239 in aerosol particles practically coincide with the same relations in fuel blown up reactor. The ratio of Cs-137/Pu-239 activities in aerosols considerably exceeds the resettlement ratio for fuel. Strontium and plutonium are in structure of fuel particles, and cesium aerosol have other origin. The analysis of changes annual radioisotopes concentration in air of towns of Belarus specifies existence of the tendency to slow decrease of contamination of atmosphere by radioisotopes of industrial origins. The basic tendency of formation of air radioactive contamination is determined by the contents of a dust at surface layer of an atmosphere and its specific activity. Annual average dust content of air in a zone resettlement was least and made about 10 mk g

  14. Sources and fate of environmental radioactivity at the earth's surface

    International Nuclear Information System (INIS)

    El-Daoushy, F.

    2010-01-01

    Sources and fate of environmental radioactivity at the earth surface This is to link environmental radioactivity to RP in Africa? To describe the benefits of Africa from this field in terms of RP, safety and security policies. To create a mission and a vision to fulfil the needs of ONE PEOPLE, ONE GOAL, ONE FAITH. Sources, processes and fate of environmental radioactivity Previous experience helps setting up an African agenda.(1) Factors influencing cosmogenic radionuclides(2) Factors influencing artificial radionuclides: (a) nuclear weapon-tests (b) nuclear accidents (c) Energy, mining and industrial waste (3) Factors influencing the global Rn-222 and its daughters. (4) Dynamics of cycles of natural radioactivity, e.g. Pb-210. (5) Environmental radiotracers act as DIAGNOSTIC TOOLS to assess air and water quality and impacts of the atmospheric and hydrospheric compartments on ecosystems.6) Definition of base-lines for rehabilitation and protection. Climate influences sources/behaviour/fate of environmental radioactivity. Impacts on life forms in Africa would be severe. Assessing environmental radioactivity resolves these issue

  15. Estimation of Uncertainty in Aerosol Concentration Measured by Aerosol Sampling System

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jong Chan; Song, Yong Jae; Jung, Woo Young; Lee, Hyun Chul; Kim, Gyu Tae; Lee, Doo Yong [FNC Technology Co., Yongin (Korea, Republic of)

    2016-10-15

    FNC Technology Co., Ltd has been developed test facilities for the aerosol generation, mixing, sampling and measurement under high pressure and high temperature conditions. The aerosol generation system is connected to the aerosol mixing system which injects SiO{sub 2}/ethanol mixture. In the sampling system, glass fiber membrane filter has been used to measure average mass concentration. Based on the experimental results using main carrier gas of steam and air mixture, the uncertainty estimation of the sampled aerosol concentration was performed by applying Gaussian error propagation law. FNC Technology Co., Ltd. has been developed the experimental facilities for the aerosol measurement under high pressure and high temperature. The purpose of the tests is to develop commercial test module for aerosol generation, mixing and sampling system applicable to environmental industry and safety related system in nuclear power plant. For the uncertainty calculation of aerosol concentration, the value of the sampled aerosol concentration is not measured directly, but must be calculated from other quantities. The uncertainty of the sampled aerosol concentration is a function of flow rates of air and steam, sampled mass, sampling time, condensed steam mass and its absolute errors. These variables propagate to the combination of variables in the function. Using operating parameters and its single errors from the aerosol test cases performed at FNC, the uncertainty of aerosol concentration evaluated by Gaussian error propagation law is less than 1%. The results of uncertainty estimation in the aerosol sampling system will be utilized for the system performance data.

  16. Characterization of aerosols in uranium handling facilities and its impact on the assessment of internal dose

    International Nuclear Information System (INIS)

    Roy, Ankush; Rao, D.D.; Sawant, Pramilla D.; Khan, Arshad; Srinivasan, P.; Chandrashekara, A.

    2016-01-01

    In nuclear facilities, compounds of uranium such as Magnesium DiUranate (MDU) U 3 O 8 , UO 2 etc. are handled in different stages of operation. There may be a possibility of intake of these compounds by radiation workers during the course of their work. The internal doses received by the workers depend not only on the quantity but also the physiochemical characteristics of the radioactive contaminant. The depositions in different regions of lung of these inhaled aerosols depend on their particle size; whereas the clearance is dependent upon the chemical nature. In this study, aerosol characterization is carried out in four different Uranium Handling Facilities (UF) for realistic assessment of internal dose to the radiation worker

  17. Aerosol and monsoon climate interactions over Asia: AEROSOL AND MONSOON CLIMATE INTERACTIONS

    Energy Technology Data Exchange (ETDEWEB)

    Li, Zhanqing [State Key Laboratory of Earth Surface Processes and Resource Ecology and College of Global Change and Earth System Science, Beijing Normal University, Beijing China; Department of Atmospheric and Oceanic Science and ESSIC, University of Maryland, College Park Maryland USA; Lau, W. K. -M. [Department of Atmospheric and Oceanic Science and ESSIC, University of Maryland, College Park Maryland USA; Ramanathan, V. [Department of Atmospheric and Climate Sciences, University of California, San Diego California USA; Wu, G. [Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing China; Ding, Y. [National Climate Center, China Meteorological Administration, Beijing China; Manoj, M. G. [Department of Atmospheric and Oceanic Science and ESSIC, University of Maryland, College Park Maryland USA; Liu, J. [Department of Atmospheric and Oceanic Science and ESSIC, University of Maryland, College Park Maryland USA; Qian, Y. [Pacific Northwest National Laboratory, Richland Washington USA; Li, J. [State Key Laboratory of Earth Surface Processes and Resource Ecology and College of Global Change and Earth System Science, Beijing Normal University, Beijing China; Zhou, T. [Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing China; Fan, J. [Pacific Northwest National Laboratory, Richland Washington USA; Rosenfeld, D. [Institute of Earth Sciences, Hebrew University, Jerusalem Israel; Ming, Y. [Geophysical Fluid Dynamic Laboratory, NOAA, Princeton New Jersey USA; Wang, Y. [Jet Propulsion Laboratory, California Institute of Technology, Pasadena California USA; Huang, J. [College of Atmospheric Sciences, Lanzhou University, Lanzhou China; Wang, B. [Department of Atmospheric Sciences, University of Hawaii, Honolulu Hawaii USA; School of Atmospheric Physics, Nanjing University of Information Science and Technology, Nanjing China; Xu, X. [Chinese Academy of Meteorological Sciences, Beijing China; Lee, S. -S. [Department of Atmospheric and Oceanic Science and ESSIC, University of Maryland, College Park Maryland USA; Cribb, M. [Department of Atmospheric and Oceanic Science and ESSIC, University of Maryland, College Park Maryland USA; Zhang, F. [State Key Laboratory of Earth Surface Processes and Resource Ecology and College of Global Change and Earth System Science, Beijing Normal University, Beijing China; Yang, X. [State Key Laboratory of Earth Surface Processes and Resource Ecology and College of Global Change and Earth System Science, Beijing Normal University, Beijing China; Zhao, C. [State Key Laboratory of Earth Surface Processes and Resource Ecology and College of Global Change and Earth System Science, Beijing Normal University, Beijing China; Takemura, T. [Research Institute for Applied Mechanics, Kyushu University, Fukuoka Japan; Wang, K. [State Key Laboratory of Earth Surface Processes and Resource Ecology and College of Global Change and Earth System Science, Beijing Normal University, Beijing China; Xia, X. [Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing China; Yin, Y. [School of Atmospheric Physics, Nanjing University of Information Science and Technology, Nanjing China; Zhang, H. [National Climate Center, China Meteorological Administration, Beijing China; Guo, J. [Chinese Academy of Meteorological Sciences, Beijing China; Zhai, P. M. [Chinese Academy of Meteorological Sciences, Beijing China; Sugimoto, N. [National Institute for Environmental Studies, Tsukuba Japan; Babu, S. S. [Space Physics Laboratory, Vikram Sarabhai Space Centre, Thiruvananthapuram India; Brasseur, G. P. [Max Planck Institute for Meteorology, Hamburg Germany

    2016-11-15

    Asian monsoons and aerosols have been studied extensively which are intertwined in influencing the climate of Asia. This paper provides a comprehensive review of ample studies on Asian aerosol, monsoon and their interactions. The region is the primary source of aerosol emissions of varies species, influenced by distinct weather and climatic regimes. On continental scale, aerosols reduce surface insolation and weaken the land-ocean thermal contrast, thus inhibiting the development of monsoons. Locally, aerosol radiative effects alter the thermodynamic stability and convective potential of the lower atmosphere leading to reduced temperatures, increased atmospheric stability, and weakened wind and atmospheric circulation. The atmospheric thermodynamic state may also be altered by the aerosol serving as cloud condensation nuclei or ice nuclei. Many mechanisms have been put forth regarding how aerosols modulate the amplitude, frequency, intensity, and phase of numerous monsoon climate variables. A wide range of theoretical, observational, and modeling findings on the Asian monsoon, aerosols, and their interactions are synthesized. A new paradigm is proposed on investigating aerosol-monsoon interactions, in which natural aerosols such as desert dust, black carbon from biomass burning, and biogenic aerosols from vegetation are considered integral components of an intrinsic aerosol-monsoon climate system, subject to external forcings of global warming, anthropogenic aerosols, and land use and change. Future research on aerosol-monsoon interactions calls for an integrated approach and international collaborations based on long-term sustained observations, process measurements, and improved models, as well as using observations to constrain model simulations and projections.

  18. Compilation of data on the release of radioactive substances in the vent air of nuclear power plants in the Federal Republic of Germany in 1975

    International Nuclear Information System (INIS)

    Winkelmann, I.; Endrulat, H.J.; Haubelt, R.; Westpfahl, U.

    1976-04-01

    The present compilation of data on the release of radioactive substances in the vent air of nuclear power plants in the FRG is a continuation of a report series on aerosol filter and iodine filter samples from the exhaust air control systems of the nuclear power plants Gundremmingen, Obrigheim, Wuergassen, Stade, Lingen and Biblis A. The reports have been issued by the Federal public health office since 1972. This report is supplemented by annual release values on radioactive noble gases, on short- and long-lived aerosols, and on gaseous 131 I, supplied by the individual nuclear power plants as in previous years on uniform questionnaires. Data on the release of tritium are also available from some nuclear power plants. (orig.) [de

  19. Investigations of the detection of α-radioactivity in samples of effluent water primary circuit and exhaust air of nuclear power plants in the FRG in the years 1973-1975

    International Nuclear Information System (INIS)

    Hoetzl, H.; Rosner, G.; Winkler, R.

    1976-05-01

    Since the middle of 1973 the α-radioactivity of aerosol filters from the stack monitoring system and since the middle of 1974 the α-radioactivity in samples from the primary cycle of the KRB was monitored. Effluent water samples of all nuclear power reactors of the FRG were also examined from the middle of 1973 till 1974. Furthermore, aerosol filters sampled in 1973 and 1974 from various places at the KRB and some aerosol filters from the stack monitoring systems of KWW (1973), KWO (1974) and KKS (1975) were also measured. Essentially, the following procedures of sample preparation for α-spectrometry of the samples in large-area gridded ionization chambers were used: cold ashing of the aerosol samples in 'excited' oxygen; coprecipitation of the alpha emitters from the effluent water samples with iron hydroxide and subsequent cold ashing of the precipitate; evaporation of the samples from the primary cycle on SS plates. The following transuranium nuclides, or some of them, were found in the samples of the primary coolant and in several aerosol filter samples: Pu-239/240, Pu-238 and/or Am-241, Cm-242 and Cm-244. Cm-242 contributes most to the α-radioactivity in fresh samples. In the effluent water samples Cm-242. Pu-239/240 and Pu-238 and/or Am-241 were identified in some cases, in one case also Cm-244. The aim of these investigations is to establish procedures for the measurement and surveillance of α-emitting nuclides in the emissions of power reactors in order to study the contribution of transuranium nuclides to the radiation exposure of the population living in the vicinity of nuclear power stations. (orig.) [de

  20. Calibration of new measuring systems to detect emissions of radioactive noble gases

    International Nuclear Information System (INIS)

    Winkelmann, I.; Kreiner, H.J.

    1977-12-01

    This report describes the calibration of different systems for the integral measurement of radioactive noble gases and the calibration of a measuring chamber for the detection of individual nuclides of radioactive noble gases in the gaseous effluent of nuclear power plants. For these measuring chambers the calibration factors for Kr-85 and Xe-133 are given as well as the detection limits to be obtained with these measuring systems for several radioactive noble gases present in the gaseous effluent at the stack of nuclear power plants. Calibration factors for Kr-85 and Xe-133 and the detection limits of this measuring method for the detections of individual nuclides of radioactive noble gases in air samples are defined taken wirh a high pressure compressor in pressure flasks an measured on a Ge(Li)-semiconductor spectrometer (pressure flask measuring method). A measuring equipment is described and calibrated which allows simultaneous measurement of activity concentration of radioactive noble gases and radioactive aerosols with a sensitivity of 2 x 10 -7 Ci/m 3 for radioactive gases and 1 x 10 -9 Ci/m 3 for radioactive particulates at a background radiation of 1 R/h. This paper is an additional report to our STH-Bericht 3/76, 'Calibration of measuring equipment for monitoring of gaseous effluents from nuclear power plants', which specifies a procedure for the calibration of measuring chambers for monitoring of gaseous radioactive effluents from nuclear power plants /1/. The calibration system used here makes it possible to simultaneously calibrate several noble gas measuring devices. (orig.) [de

  1. Fusion radioactivity confinement and application to postulated ITER accidents

    International Nuclear Information System (INIS)

    Piet, S.J.; Brereton, S.J.

    1991-01-01

    An assessment of the ITER radioactivity confinement shows reduction of potential accidental releases to the environment by two orders of magnitude. Important credits are the 1% volume/day confinement leakage rate, radioactivity decay for short-lived isotopes, resumption of detritiation/negative pressure within seven days of the accident, and wind meander during the slow confinement leakage. Achieving this two order of magnitude credit in practice requires appropriate design details, especially the leakage rate and detritiation/negative pressure equipment, and research to validate some key assumptions. The confinement maximizes dependence on passive safety features, thereby working toward using fusion's potential safety advantages. The confinement includes several confinement zones with varying human access allowances. Some confinement areas are normally isolated from the environment, the closed ventilation zone. Some areas have an inert cover gas to inhibit combustion. If future assessments of accidental overpressure show the need, we propose a filter/vent system. This report documents our work for the ITER Conceptual Design Activity (CDA). The report is consistent with the final CDA design reports and descriptions, except that our analysis includes a filter/vent. For gaseous or vapor tritium and for most activated aerosols, the reference release fraction is about 2%. For short-lived tungsten-rhenium aerosols, the reference release fraction is somewhat lower, as low as 0.5% for some accident scenarios. Even without resumption of detritiation/decontamination or negative pressure within seven days of the accident, the release fraction for stays below 4%

  2. Aerosolization, Chemical Characterization, Hygroscopicity and Ice Formation of Marine Biogenic Particles

    Science.gov (United States)

    Alpert, P. A.; Radway, J.; Kilthau, W.; Bothe, D.; Knopf, D. A.; Aller, J. Y.

    2013-12-01

    The oceans cover the majority of the earth's surface, host nearly half the total global primary productivity and are a major source of atmospheric aerosol particles. However, effects of biological activity on sea spray generation and composition, and subsequent cloud formation are not well understood. Our goal is to elucidate these effects which will be particularly important over nutrient rich seas, where microorganisms can reach concentrations of 10^9 per mL and along with transparent exopolymer particles (TEP) can become aerosolized. Here we report the results of mesocosm experiments in which bubbles were generated by two methods, either recirculating impinging water jets or glass frits, in natural or artificial seawater containing bacteria and unialgal cultures of three representative phytoplankton species, Thalassiosira pseudonana, Emiliania huxleyi, and Nannochloris atomus. Over time we followed the size distribution of aerosolized particles as well as their hygroscopicity, heterogeneous ice nucleation potential, and individual physical-chemical characteristics. Numbers of cells and the mass of dissolved and particulate organic carbon (DOC, POC), TEP (which includes polysaccharide-containing microgels and nanogels >0.4 μm in diameter) were determined in the bulk water, the surface microlayer, and aerosolized material. Aerosolized particles were also impacted onto substrates for ice nucleation and water uptake experiments, elemental analysis using computer controlled scanning electron microscopy and energy dispersive analysis of X-rays (CCSEM/EDX), and determination of carbon bonding with scanning transmission X-ray microscopy and near-edge X-ray absorption fine structure spectroscopy (STXM/NEXAFS). Regardless of bubble generation method, the overall concentration of aerosol particles, TEP, POC and DOC increased as concentrations of bacterial and phytoplankton cells increased, stabilized, and subsequently declined. Particles cloud formation and potential

  3. The aerosols and the greenhouse effect; Aerosoler og klimaeffekten

    Energy Technology Data Exchange (ETDEWEB)

    Iversen, Trond; Kirkevaag, Alf; Seland, Oeyvind; Debernard, Jens Boldingh; Kristjansson, Jon Egill; Storelvmo, Trude

    2008-07-01

    The article discussed the aerosol effects on the climatic changes and points out that the climate models do not incorporate these components satisfactorily mostly due to insufficient knowledge of the aerosol pollution sources. The direct and indirect effects of aerosols are mentioned as well as the climate response (tk)

  4. Measurement of environmental radioactivity in Toki district

    International Nuclear Information System (INIS)

    1981-11-01

    When the Institute of Plasma Physics, Nagoya University, expressed the hope to move into Toki district, the environmental problems accompanying the movement were discussed. The effect of the radioactivity leaking from the nuclear facility on human bodies must be far smaller than that of natural radiation, and for the purpose, the amount and fluctuation range of the natural radiation in the district must be known. The initial objectives of this cooperative research were to study on environmental radiation and to make a Geiger counter for the measurement. In 1981, a scintillation counter will be completed, and using a multi-channel pulse height analyzer, the nuclides which are the source of environmental radiation emission will be identified, and the tritium in natural water will be detected. Thus, the evaluation of environmental radiation can be carried out, and the situation before the movement of the research facility can be grasped. In this paper, the natural radioactivity in earth, atmosphere and water and cosmic ray, artificial radioactivity, and environmental radiation exposure dose are reported. Also, the manufacture of a GM counter measuring instrument and the measurements of cosmic ray background, typical earth samples and environmental radioactivity with the GM counter are reported. The related data are attached. (Kako, I.)

  5. Determination of radon daughter activities of different aerosol fractions by gross-α and gross-β measurements

    International Nuclear Information System (INIS)

    Katona, T.; Kanyar, B.; Jobbagy, V.; Kavasi, N.; Molnar, A.; Imre, K.

    2004-01-01

    The aim was to determine the radioactivities of the radon progenies ( 218 Po, 214 Pb, 214 Bi and 214 Po) attached to the carrier aerosol particles with respect to the size distribution in order to improve the assessment of the inhalation dose. We derived the radionuclide-specific activity concentrations from gross alpha and gross beta measurements provided during 2 hours after sampling and model calculations including parameter estimation. For the aerosol sampling we used an electrical low pressure impactor, which is able to collect aerosol particles in 12 different diameter ranges. In our test investigations the aerosol particles were collected from a closed chamber in a common laboratory building. The chamber contained a relatively high radon concentration (60-90 kBq/m 3 ) in equilibrium with the short lived daughters generated previously without any additional aerosol sources. For the nuclear measurements of the aerosol samples ZnS/plastic sandwich detectors have been used. The time series data of gross alpha and gross beta activities were fitted simultaneously and the initial activities of the daughters were estimated. According to the results from two different fractions (0.06 and 0.7 μm) just followed the end of sampling they contain a higher 218 Po activity than the 214 Pb and 214 Bi ones. The preliminary assessments for the special air conditions show that the 214 Pb-to- 218 Po activity ratios are higher for the small aerosol particles than for the larger ones. The estimated errors of the initial activities were near to 50% in a large part of cases. (author)

  6. Correlation between Asian Dust and Specific Radioactivities of Fission Products Included in Airborne Samples in Tokushima, Shikoku Island, Japan, Due to the Fukushima Nuclear Accident

    Energy Technology Data Exchange (ETDEWEB)

    Sakama, M., E-mail: minorusakama@tokushima-u.ac.jp [Department of Radiological Science, Division of Biomedical Information Sciences, Institute of Health Biosciences, The University of Tokushima, Tokushima 770-8509 (Japan); Nagano, Y. [Department of Radiological Science, Division of Biomedical Information Sciences, Institute of Health Biosciences, The University of Tokushima, Tokushima 770-8509 (Japan); Kitade, T. [Department of Laboratory, M and S Instruments Inc., Osaka 532-0005 (Japan); Shikino, O. [Department of Inorganic Analysis, PerkinElmer Japan Co. Ltd., Yokohama 240-0005 (Japan); Nakayama, S. [Department of Nuclear Science, Institute of Socio-Arts and Sciences, The University of Tokushima, Tokushima 770-8502 (Japan)

    2014-06-15

    Radioactive fission product {sup 131}I released from the Fukushima Daiichi Nuclear Power Plants (FD-NPP) was first detected on March 23, 2011 in an airborne aerosol sample collected at Tokushima, Shikoku Island, located in western Japan. Two other radioactive fission products, {sup 134}Cs and {sup 137}Cs were also observed in a sample collected from April 2 to 4, 2011. The maximum specific radioactivities observed in this work were about 2.5 to 3.5 mBq×m{sup -3} in a airborne aerosol sample collected on April 6. During the course of the continuous monitoring, we also made our first observation of seasonal Asian Dust and those fission products associated with the FDNPP accident concurrently from May 2 to 5, 2011. We found that the specific radioactivities of {sup 134}Cs and {sup 137}Cs decreased drastically only during the period of Asian Dust. And also, it was found that this trend was very similar to the atmospheric elemental concentration (ng×m{sup -3}) variation of stable cesium ({sup 133}Cs) quantified by elemental analyses using our developed ICP-DRC-MS instrument.

  7. Environmental radioactivity and radiation exposure in 2015; Umweltradioaktivitaet und Strahlenbelastung im Jahr 2015

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2017-07-20

    The information of the German Federal Government on the environmental radioactivity and radiation exposure in 2015 covers the following issues: selected topics of radiation protection, natural radiation exposure; civilizing (artificial) radiation exposure: nuclear power plants and other nuclear facilities, uranium mine recultivation, radioactive materials in industry and households, fallout from nuclear weapon testing and reactor accidents; occupational radiation exposure: exposed personnel in nuclear facilities, aviation personnel, radiation accidents; medical radiation exposure: nuclear medical diagnostics and therapy; non-ionizing radiation: electromagnetic fields, UV radiation, optical radiation.

  8. Evaluation of precipitation scavenging rates of background aerosol

    International Nuclear Information System (INIS)

    Hicks, B.B.

    1976-01-01

    An attempt was made to obtain information on the rates at which raining clouds cleanse the atmosphere, with natural radioactivity used as a tracer of naturally-occurring aerosols. In the atmosphere, the air concentrations of the radioactive Rn daughters would be expected to approach equilibrium with increasing height. In a theoretical study, Jacobi et al. (1959) showed that the short-lived first daughter of radon ( 218 Po, 3 min half life) is in equilibrium with radon above about 20 m. Gamma-ray spectrometry was used to measure the isotopes of interest in successive samples of precipitation collected at ground level during nine rainfall occasions. Gamma-ray spectra of freshly collected rainfall were typically dominated by the photopeaks at 0.352 MeV ( 214 Pb) and 0.609 MeV( 214 Bi). After these isotopes have decayed, the 212 Pb photopeak at 0.323 MeV becomes apparent ( 212 Pb is a thoron daughter). In the present work this feature was employed to allow accurate measurement of each isotope

  9. Aerial spraying to capture released radioactivity from NPP in a severe accident

    Energy Technology Data Exchange (ETDEWEB)

    Younus, Irfan; Yim, Man Sung [KAIST, Daejeon (Korea, Republic of); Medard, Thiphaine [Ecole des Mines de Saint-Etienne, Daejeon (Korea, Republic of)

    2016-05-15

    The proposed strategy in this paper is the use of aqueous spray (water/foam) mixed with suitable chemical additives to capture, dissolve and stabilize the radioactive gases and aerosol particles released from leaked reactor containment and auxiliary building. The spray system can be approached to the leaked reactor building through the use of a truck with high rising cranes, unmanned aerial vehicles (UAVs, such as helicopters), aerostats, or by installing fixed piping structure around the containment building depending on the accident situation. Laboratory-scale experimental system was setup to examine the performance of such systems. The alkaline water (aqueous NaOH.Na{sub 2}S{sub 2}O{sub 3}) and foam-based spray material (sodium lauryl sulphate) were used to examine capture efficiency of gaseous iodine and aerosol particles. The gaseous iodine and aerosol removal efficiency of foam-based spray is higher when compared with alkaline water-based spray. 2. The nozzle producing full cone spray provides the better removal efficiency than nozzle producing hollow cone spray patterns.

  10. 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

  11. Location iron-Mantua an area with high securities gives natural radioactivity

    International Nuclear Information System (INIS)

    Alcaide Orpi, J.; Oliveira Acosta, J.; Valdes Hernadez, G.M.; Leal Ramirez, M.R.; Blanco Jorrin, N.

    1998-01-01

    The work shows the high natural radioactivity and the concentration to the natural radioelements (U,Th, Ra, K) it is exists in the sulfurous Hierro Mantua location. The objective is to know the possible radiological risk to that would be subjected the workers during the mining exploitation, because the high gamma radiation doses that could receive and to the risks product the internal contamination due to the inhalation the radon 222 and uranium aerosols and particles

  12. Sources and formation mechanisms of carbonaceous aerosol at a regional background site in the Netherlands : insights from a year-long radiocarbon study

    NARCIS (Netherlands)

    Dusek, Ulrike; Hitzenberger, Regina; Kasper-Giebl, Anne; Kistler, Magdalena; Meijer, Harro A. J.; Szidat, Sonke; Wacker, Lukas; Holzinger, Rupert; Rockmann, Thomas

    2017-01-01

    We measured the radioactive carbon isotope C-14 (radiocarbon) in various fractions of the carbonaceous aerosol sampled between February 2011 and March 2012 at the Cesar Observatory in the Netherlands. Based on the radiocarbon content in total carbon (TC), organic carbon (OC), water-insoluble organic

  13. Natural and artificial radioactivity in commercial food for domestic animals; Avaliação da radioatividade natural e artificial em rações comerciais para animais domésticos

    Energy Technology Data Exchange (ETDEWEB)

    Cavalcante, Fernanda

    2017-07-01

    The levels of natural radioactivity throughout the planet and their eventual consequences are studied by Environmental Radioprotection. Over the past years, the international agencies concerned with radiation protection have debated over the practices conducted so far, regarding the protection of the fauna and ora, which believed that the recommendations implemented for human beings assured that other species were also protected. Thus, assessments of the activity concentration of different radionuclides in the environment, as well as the absorbed doses for species from different ecosystems, due to internal and external exposures, are needed. Brazil holds the second largest dog and cat population in the world and annually produces over 2 million tons of feed. The present work has investigated the radioactivity levels in commercial brands of dry dog and cat food, using high resolution gamma spectrometry. The results have shown activity concentrations for artificial radionuclides below the detector's Minimum Detectable Activity and also, low concentration levels for the natural radionuclides, varying from 0,9 ± 0,3 Bq/kg up to 5,1 ± 0,7 Bq/kg for {sup 226}Ra, from 1,2 ± 0,4 Bq/kg up to 11,1 ± 1,0 Bq/kg for {sup 232}Th and from 156 ± 7 Bq/kg up to 410± 19 Bq/kg for {sup 40}K. In order to verify the mineral content in pet food, EDXRF technique was applied and, using multivariate statistics, correlations between the mineral and radionuclide content were verified. The good correlation observed between concentrations of {sup 226}Ra, {sup 232}Th and calcium could be associated with meat and bone our used in feed manufacturing. The internal dose for some organs were inferred by Monte Carlo method and the results were no higher than 1 μGy/day. In summary, results have shown that the activity levels found in the pet food are low enough to conclude that the brands evaluated carry no radiological risks for the animals that consume them. (author)

  14. Black carbon aerosol mixing state, organic aerosols and aerosol optical properties over the United Kingdom

    Science.gov (United States)

    McMeeking, G. R.; Morgan, W. T.; Flynn, M.; Highwood, E. J.; Turnbull, K.; Haywood, J.; Coe, H.

    2011-09-01

    Black carbon (BC) aerosols absorb sunlight thereby leading to a positive radiative forcing and a warming of climate and can also impact human health through their impact on the respiratory system. The state of mixing of BC with other aerosol species, particularly the degree of internal/external mixing, has been highlighted as a major uncertainty in assessing its radiative forcing and hence its climate impact, but few in situ observations of mixing state exist. We present airborne single particle soot photometer (SP2) measurements of refractory BC (rBC) mass concentrations and mixing state coupled with aerosol composition and optical properties measured in urban plumes and regional pollution over the United Kingdom. All data were obtained using instrumentation flown on the UK's BAe-146-301 large Atmospheric Research Aircraft (ARA) operated by the Facility for Airborne Atmospheric Measurements (FAAM). We measured sub-micron aerosol composition using an aerosol mass spectrometer (AMS) and used positive matrix factorization to separate hydrocarbon-like (HOA) and oxygenated organic aerosols (OOA). We found a higher number fraction of thickly coated rBC particles in air masses with large OOA relative to HOA, higher ozone-to-nitrogen oxides (NOx) ratios and large concentrations of total sub-micron aerosol mass relative to rBC mass concentrations. The more ozone- and OOA-rich air masses were associated with transport from continental Europe, while plumes from UK cities had higher HOA and NOx and fewer thickly coated rBC particles. We did not observe any significant change in the rBC mass absorption efficiency calculated from rBC mass and light absorption coefficients measured by a particle soot absorption photometer despite observing significant changes in aerosol composition and rBC mixing state. The contributions of light scattering and absorption to total extinction (quantified by the single scattering albedo; SSA) did change for different air masses, with lower SSA

  15. Black carbon aerosol mixing state, organic aerosols and aerosol optical properties over the United Kingdom

    Directory of Open Access Journals (Sweden)

    G. R. McMeeking

    2011-09-01

    Full Text Available Black carbon (BC aerosols absorb sunlight thereby leading to a positive radiative forcing and a warming of climate and can also impact human health through their impact on the respiratory system. The state of mixing of BC with other aerosol species, particularly the degree of internal/external mixing, has been highlighted as a major uncertainty in assessing its radiative forcing and hence its climate impact, but few in situ observations of mixing state exist. We present airborne single particle soot photometer (SP2 measurements of refractory BC (rBC mass concentrations and mixing state coupled with aerosol composition and optical properties measured in urban plumes and regional pollution over the United Kingdom. All data were obtained using instrumentation flown on the UK's BAe-146-301 large Atmospheric Research Aircraft (ARA operated by the Facility for Airborne Atmospheric Measurements (FAAM. We measured sub-micron aerosol composition using an aerosol mass spectrometer (AMS and used positive matrix factorization to separate hydrocarbon-like (HOA and oxygenated organic aerosols (OOA. We found a higher number fraction of thickly coated rBC particles in air masses with large OOA relative to HOA, higher ozone-to-nitrogen oxides (NOx ratios and large concentrations of total sub-micron aerosol mass relative to rBC mass concentrations. The more ozone- and OOA-rich air masses were associated with transport from continental Europe, while plumes from UK cities had higher HOA and NOx and fewer thickly coated rBC particles. We did not observe any significant change in the rBC mass absorption efficiency calculated from rBC mass and light absorption coefficients measured by a particle soot absorption photometer despite observing significant changes in aerosol composition and rBC mixing state. The contributions of light scattering and absorption to total extinction (quantified by the single scattering albedo; SSA did change for

  16. Leaching of artificial radionuclide out of minerals

    International Nuclear Information System (INIS)

    Bogdanov, R.V.; Osipova, I.V.; Sergeev, A.S.

    1992-01-01

    Leaching of radionuclides induced by neutron bombardment in natural silicates and silicophosphate of rare earth elements and calcium, is studied using gamma-spectrometry. It is shown that solution of minerals under the effect of artificial subsoil water at 75 deg C is incongruent character: difference in leaching of cobalt and actinides reaches value equal to two magnitudes. Behaviour of lanthanides as analogs of transplutonium elements is of special interest. Essential role of specimen microphase composition is pointed out. The suggested methodological approach is efficient at selection of matricies for fixaton of radioactive wastes

  17. Spent fuel sabotage test program, characterization of aerosol dispersal : interim final report

    International Nuclear Information System (INIS)

    Gregson, Michael Warren; Brockmann, John E.; Loiseau, Olivier; Klennert, Lindsay A.; Nolte, Oliver; Molecke, Martin Alan; Autrusson, Bruno A.; Koch, Wolfgang; Pretzsch, Gunter Guido; Brucher, Wenzel; Steyskal, Michele D.

    2008-01-01

    This multinational, multi-phase spent fuel sabotage test program is quantifying the aerosol particles produced when the products of a high energy density device (HEDD) interact with and explosively particulate test rodlets that contain pellets of either surrogate materials or actual spent fuel. This program provides source-term data that are relevant to plausible sabotage scenarios in relation to spent fuel transport and storage casks and associated risk assessments. We present details and significant results obtained from this program from 2001 through 2007. Measured aerosol results include: respirable fractions produced; amounts, nuclide content, and produced particle size distributions and morphology; measurements of volatile fission product species enhanced sorption--enrichment factors onto respirable particles; and, status on determination of the spent fuel ratio, SFR, needed for scaling studies. Emphasis is provided on recent Phase 3 tests using depleted uranium oxide pellets plus non-radioactive fission product dopants in surrogate spent fuel test rodlets, plus the latest surrogate cerium oxide results and aerosol laboratory supporting calibration work. The DUO 2 , CeO 2 , plus fission product dopant aerosol particle results are compared with available historical data. We also provide a status review on continuing preparations for the final Phase 4 in this program, tests using individual short rodlets containing actual spent fuel from U.S. PWR reactors, with both high- and lower-burnup fuel. The source-term data, aerosol results, and program design have been tailored to support and guide follow-on computer modeling of aerosol dispersal hazards and radiological consequence assessments. This spent fuel sabotage, aerosol test program was performed primarily at Sandia National Laboratories, with support provided by both the U.S. Department of Energy and the Nuclear Regulatory Commission. This program has significant input from, and is cooperatively supported and

  18. Spent fuel sabotage test program, characterization of aerosol dispersal : interim final report.

    Energy Technology Data Exchange (ETDEWEB)

    Gregson, Michael Warren; Brockmann, John E.; Loiseau, Olivier (Institut de Radioprotection et de Surete Nucleaire, France); Klennert, Lindsay A.; Nolte, Oliver (Fraunhofer Institut fur Toxikologie und Experimentelle Medizin, Germany); Molecke, Martin Alan; Autrusson, Bruno A. (Institut de Radioprotection et de Surete Nucleaire, France); Koch, Wolfgang (Fraunhofer Institut fur Toxikologie und Experimentelle Medizin, Germany); Pretzsch, Gunter Guido (Gesellschaft fur Anlagen- und Reaktorsicherheit, Germany); Brucher, Wenzel (Gesellschaft fur Anlagen- und Reaktorsicherheit, Germany); Steyskal, Michele D.

    2008-03-01

    This multinational, multi-phase spent fuel sabotage test program is quantifying the aerosol particles produced when the products of a high energy density device (HEDD) interact with and explosively particulate test rodlets that contain pellets of either surrogate materials or actual spent fuel. This program provides source-term data that are relevant to plausible sabotage scenarios in relation to spent fuel transport and storage casks and associated risk assessments. We present details and significant results obtained from this program from 2001 through 2007. Measured aerosol results include: respirable fractions produced; amounts, nuclide content, and produced particle size distributions and morphology; measurements of volatile fission product species enhanced sorption--enrichment factors onto respirable particles; and, status on determination of the spent fuel ratio, SFR, needed for scaling studies. Emphasis is provided on recent Phase 3 tests using depleted uranium oxide pellets plus non-radioactive fission product dopants in surrogate spent fuel test rodlets, plus the latest surrogate cerium oxide results and aerosol laboratory supporting calibration work. The DUO{sub 2}, CeO{sub 2}, plus fission product dopant aerosol particle results are compared with available historical data. We also provide a status review on continuing preparations for the final Phase 4 in this program, tests using individual short rodlets containing actual spent fuel from U.S. PWR reactors, with both high- and lower-burnup fuel. The source-term data, aerosol results, and program design have been tailored to support and guide follow-on computer modeling of aerosol dispersal hazards and radiological consequence assessments. This spent fuel sabotage, aerosol test program was performed primarily at Sandia National Laboratories, with support provided by both the U.S. Department of Energy and the Nuclear Regulatory Commission. This program has significant input from, and is cooperatively

  19. Characterization of urban aerosol in Cork city (Ireland) using aerosol mass spectrometry

    Science.gov (United States)

    Dall'Osto, M.; Ovadnevaite, J.; Ceburnis, D.; Martin, D.; Healy, R. M.; O'Connor, I. P.; Kourtchev, I.; Sodeau, J. R.; Wenger, J. C.; O'Dowd, C.

    2013-05-01

    Ambient wintertime background urban aerosol in Cork city, Ireland, was characterized using aerosol mass spectrometry. During the three-week measurement study in 2009, 93% of the ca. 1 350 000 single particles characterized by an Aerosol Time-of-Flight Mass Spectrometer (TSI ATOFMS) were classified into five organic-rich particle types, internally mixed to different proportions with elemental carbon (EC), sulphate and nitrate, while the remaining 7% was predominantly inorganic in nature. Non-refractory PM1 aerosol was characterized using a High Resolution Time-of-Flight Aerosol Mass Spectrometer (Aerodyne HR-ToF-AMS) and was also found to comprise organic aerosol as the most abundant species (62%), followed by nitrate (15%), sulphate (9%) and ammonium (9%), and chloride (5%). Positive matrix factorization (PMF) was applied to the HR-ToF-AMS organic matrix, and a five-factor solution was found to describe the variance in the data well. Specifically, "hydrocarbon-like" organic aerosol (HOA) comprised 20% of the mass, "low-volatility" oxygenated organic aerosol (LV-OOA) comprised 18%, "biomass burning" organic aerosol (BBOA) comprised 23%, non-wood solid-fuel combustion "peat and coal" organic aerosol (PCOA) comprised 21%, and finally a species type characterized by primary {m/z} peaks at 41 and 55, similar to previously reported "cooking" organic aerosol (COA), but possessing different diurnal variations to what would be expected for cooking activities, contributed 18%. Correlations between the different particle types obtained by the two aerosol mass spectrometers are also discussed. Despite wood, coal and peat being minor fuel types used for domestic space heating in urban areas, their relatively low combustion efficiencies result in a significant contribution to PM1 aerosol mass (44% and 28% of the total organic aerosol mass and non-refractory total PM1, respectively).

  20. Characterization of urban aerosol in Cork city (Ireland using aerosol mass spectrometry

    Directory of Open Access Journals (Sweden)

    M. Dall'Osto

    2013-05-01

    Full Text Available Ambient wintertime background urban aerosol in Cork city, Ireland, was characterized using aerosol mass spectrometry. During the three-week measurement study in 2009, 93% of the ca. 1 350 000 single particles characterized by an Aerosol Time-of-Flight Mass Spectrometer (TSI ATOFMS were classified into five organic-rich particle types, internally mixed to different proportions with elemental carbon (EC, sulphate and nitrate, while the remaining 7% was predominantly inorganic in nature. Non-refractory PM1 aerosol was characterized using a High Resolution Time-of-Flight Aerosol Mass Spectrometer (Aerodyne HR-ToF-AMS and was also found to comprise organic aerosol as the most abundant species (62%, followed by nitrate (15%, sulphate (9% and ammonium (9%, and chloride (5%. Positive matrix factorization (PMF was applied to the HR-ToF-AMS organic matrix, and a five-factor solution was found to describe the variance in the data well. Specifically, "hydrocarbon-like" organic aerosol (HOA comprised 20% of the mass, "low-volatility" oxygenated organic aerosol (LV-OOA comprised 18%, "biomass burning" organic aerosol (BBOA comprised 23%, non-wood solid-fuel combustion "peat and coal" organic aerosol (PCOA comprised 21%, and finally a species type characterized by primary extit{m/z}~peaks at 41 and 55, similar to previously reported "cooking" organic aerosol (COA, but possessing different diurnal variations to what would be expected for cooking activities, contributed 18%. Correlations between the different particle types obtained by the two aerosol mass spectrometers are also discussed. Despite wood, coal and peat being minor fuel types used for domestic space heating in urban areas, their relatively low combustion efficiencies result in a significant contribution to PM1 aerosol mass (44% and 28% of the total organic aerosol mass and non-refractory total PM1, respectively.