WorldWideScience

Sample records for radon transport processes

  1. Radon Optical Processing in Radon Space.

    Science.gov (United States)

    1986-06-15

    and have been considered at length elsewhere (Rowland, 1979) (3arrett and Swindell , 1981) . Rather, we wish to investigate the use of the Radon... Swindell :1977, 1981) or Larrett (1984). We can also express the inverse Radon transform in operator notation (Barrett, 1984), expanding the operator PR...similar signal processing capability over a wide range of input frequencies ( Roberts , 1977). fe Linear FM, or chirp, SAW filters are easily made and have

  2. Modelling of radon transport in porous media

    NARCIS (Netherlands)

    van der Graaf, E.R.; de Meijer, R.J.; Katase, A; Shimo, M

    1998-01-01

    This paper aims to describe the state of the art of modelling radon transport in soil on basis of multiphase radon transport equations. Emphasis is given to methods to obtain a consistent set of input parameters needed For such models. Model-measurement comparisons with the KVI radon transport

  3. The radon 222 transport in soils. The case of the storage of residues coming from uranium ores processing; La migration du radon 222 dans un sol. Application aux stockages de residus issus du traitement des minerais d'uranium

    Energy Technology Data Exchange (ETDEWEB)

    Ferry, C

    2000-07-01

    Uranium Mill Tailings (UMT) contain comparatively large quantities of radium-226. This radionuclide yields, by radioactive decay, the radioactive gas radon-222. Tailing piles are routinely covered to reduce the radon release-rate into the atmosphere. In order to assess the long term environmental impact of a UMT repository, mechanisms governing radon exhalation at the soil surface must be deciphered and understood. A model of radon transport in the unsaturated zone is developed for this purpose: water- and air-flow in the porous material are determined, as well as radon transport by diffusion in the pore space and advection by the gas phase. The radon transport model in the unsaturated zone - TRACI (which stands, in French, for Radon Transport within the Unsaturated Layer) - calculates moisture contents in the soil, Darcy's velocities of the liquid and gas phases, radon concentrations in the gas phase and radon flux at the soil surface. TRACI's results are compared with observations carried out on a UMT and a cover layer. Input parameters are derived from the textural analysis of the material under study, whereas upper boundary conditions are given by meteorological data. If we consider measurement errors and uncertainties on the porous medium characterisation, model's results are generally in good agreement with observations, at least on the long run. Moreover, data analysis shows hat transient phenomena are understood as well, in most situations. (author)

  4. Radon

    Science.gov (United States)

    ... or Measurement and Mitigation Professional Radon in Drinking Water Radon Hotlines and Resources ( En Español ) Radon Publications ( En Español ) En Español - Acerca del radón Home Buyers and Sellers Radon Protection: Buying a Home Radon Protection: Building a Home ...

  5. Radon transport in fractured soil. Laboratory experiments and modelling

    Energy Technology Data Exchange (ETDEWEB)

    Hoff, A.

    1997-10-01

    Radon (Rn-222) transport in fractured soil has been investigated by laboratory experiments and by modelling. Radon transport experiments have been performed with two sand columns (homogeneous and inhomogeneous) and one undisturbed clayey till column containing a net of preferential flow paths (root holes). A numerical model (the finite-element model FRACTRAN) and an analytic model (a pinhole model) have been applied in simulations if soil gas and radon transport in fractured soil. Experiments and model calculations are included in a discussion of radon entry rates into houses placed on fractured soil. The main conclusion is, that fractures does not in general alter transport of internally generated radon out of soil, when the pressure and flow conditions in the soil is comparable to the conditions prevailing under a house. This indicates the important result, that fractures in soil have no impact on radon entry into a house beyond that of an increased gas permeability, but a more thorough investigation of this subject is needed. Only in the case where the soil is exposed to large pressure gradients, relative to gradients induced by a house, may it be possible to observe effects of radon exchange between fractures and matrix. (au) 52 tabs., 60 ill., 5 refs.

  6. Radon

    Science.gov (United States)

    ... forming a different element with different radioactive properties. Radium and then radon are formed midway through these ... the main source of health concerns. The main isotope of health concern is radon-222 ( 222 Rn). ...

  7. Mass transport of heavy metal ions and radon in gels used as sealing agents in containment technologies

    Energy Technology Data Exchange (ETDEWEB)

    Lakatos, I.; Bauer, K.; Lakatos-Szabo, J. [Research Lab. for Mining Chemistry, Miskolc-Egyetemvaros (Hungary); Kretzschmar, H.J. [DBI Gas- und Umwelttechnik GmbH, Feiberg (Germany)

    1997-12-31

    The diffusion and hydrodynamic mass transport of multivalent cations, mostly Cr(III) and Cr(VI) ions and radon in polymer/silicate gels and Montanwax emulsions were studied. It was concluded that the self-conforming gels may decrease the hydrodynamic mass transport in porous and fractured media by 4-6 orders of magnitude. In water saturated systems, however, the diffusion transport can be restricted by hydrogels only to a moderate extent. On the other hand, the high and selective retention capacity of gels towards different diffusing species may open new vistas in the sealing technologies. Similar results were obtained for transport phenomena of radon. The almost perfect quenching process of radon and its nuclides in gels and emulsions further enhances the positive effects of the encapsulation methods. The laboratory experiments provided valuable new information to design the different containment technologies.

  8. An experimental setup for measuring generation and transport of radon in building materials

    NARCIS (Netherlands)

    van der Pal, M.; Hendriks, N.A.; de Meijer, R.J.; van der Graaf, E.R.; de Wit, M.H.

    2001-01-01

    This study describes an approach for measuring and modelling diffusive and advective transport of radon through building materials. The goal of these measurements and model calculations is to improve our understanding concerning the factors influencing the transport of radon through building

  9. Moisture dependence of radon transport in concrete : Measurements and modeling

    NARCIS (Netherlands)

    Cozmuta, [No Value; van der Graaf, ER; de Meijer, RJ

    2003-01-01

    The moisture dependence of the radon-release rate of concrete was measured under well controlled conditions. It was found that the radon-release rate almost linearly increases up to moisture contents of 50 to 60%. At 70 to 80% a maximum was found and for higher moisture contents the radon-release

  10. Measurements on, and modelling of diffusive and advective radon transport in soil

    DEFF Research Database (Denmark)

    Graff, E.R. van der; Witteman, G.A.A.; Spoel, W.H. van der

    1994-01-01

    Results are presented of measurements on radon transport in soil under controlled conditions with a laboratory facility consisting of a stainless steel vessel (height and diameter 2 m) filled with a uniform column of sand. At several depths under the sand surface, probes are radially inserted...... into the vessel to measure the radon concentration in the soil gas. To study advective radon transport a perforated circular box is placed in the sand close to the bottom of the vessel. By pressurising this box, an air flow through the sand column is induced. Radon concentration profiles were measured without...... an air flow as a function of time, and for several values of the air flow, equilibrium radon concentration profiles were measured....

  11. Radon transport modelling: User's guide to RnMod3d

    DEFF Research Database (Denmark)

    Andersen, Claus Erik

    2000-01-01

    RnMod3d is a numerical computer model of soil-gas and radon transport in porous media. It can be used, for example, to study radon entry from soil into houses in response to indoor-outdoor pressure differences or changes in atmospheric pressure. It canalso be used for flux calculations of radon...... be anisotropic. This guide includes benchmark tests based on simpleproblems with known solutions. RnMod3d has also been part of an international model intercomparison exercise based on more complicated problems without known solutions. All tests show that RnMod3d gives results of good quality....... from the soil surface or to model radon exhalation from building materials such as concrete. The finite-volume model is a technical research tool, and it cannot be used meaningfully without good understandingof the involved physical equations. Some understanding of numerical mathematics...

  12. Comparison of two numerical modelling approaches to a field experiment of unsaturated radon transport in a covered uranium mill tailings soil (Lavaugrasse, France)

    Energy Technology Data Exchange (ETDEWEB)

    Saadi, Zakaria; Guillevic, Jerome [Institut de Radioprotection et de Surete Nucleaire (IRSN), PRP-DGE/SEDRAN/BRN, 31 avenue de la Division Leclerc, B.P. 17, 92262, Fontenay-aux-Roses, Cedex (France)

    2014-07-01

    Uncertainties on the mathematical modelling of radon transport in an unsaturated covered uranium mill tailings (UMT) soil at field scale can have a great impact on the estimation of the average measured radon flux to the atmosphere at the landfill cover, which must be less than the threshold value 0.74 Bq.m{sup -2}.s{sup -1}recommended by the federal standard (EPA 40 CFR 192). These uncertainties are usually attributed to the numerical errors from the numerical schemes dealing with soil layering and to inadequate representations of the modelling of physical processes at the soil/plant/atmosphere interface and of the soil hydraulic and transport properties, as well as their parameterization. In this work, we compare one-dimensional simulation results from two numerical models of two-phase (water-air) porous media flow and radon transport to the data of radon activity exhalation flux and depth-volumetric concentration measured during a field campaign from June to November of 1999 in a two-layered soil of 1.3 m thickness (i.e., cover material/UMT: 0.5/0.8 m) of an experimental pond located at the Lavaugrasse UMT-landfill site (France). The first numerical modelling approach is a coupled finite volume compositional (i.e., water, radon, air) transport model (TOUGH2/EOS7Rn code, Saadi et al., 2013), while the second one is a decoupled finite difference one-component (i.e., radon) transport model (TRACI code, Ferry et al., 2001). Transient simulations during six month of hourly rainfall and atmospheric pressure variations showed that calculations from the one-component transport model usually overestimate both measured radon exhalation flux and depth-concentration. However, considering the effective unsaturated pore air-component diffusivity to be different from that of the radon-component in the compositional transport model allowed to significantly enhancing the modelling of these radon experimental data. The time-averaged radon flux calculated by EOS7Rn (3.42 Bq

  13. MEASUREMENTS ON, AND MODELING OF DIFFUSIVE AND ADVECTIVE RADON TRANSPORT IN SOIL

    NARCIS (Netherlands)

    VANDERGRAAF, ER; WITTEMAN, GAA; VANDERSPOEL, WH; ANDERSEN, CE; DEMEIJER, RJ

    1994-01-01

    Results are presented of measurements on radon transport in soil under controlled conditions with a laboratory facility consisting of a stainless steel vessel (height and diameter 2 m) filled with a uniform column of sand. At several depths under the sand surface, probes are radially inserted into

  14. Signal processing of diurnal and semidiurnal variations in radon and atmospheric pressure: A new tool for accurate in situ measurement of soil gas velocity, pressure gradient, and tortuosity

    Science.gov (United States)

    Pinault, Jean-Louis; Baubron, Jean-Claude

    1997-08-01

    Signal processing of diurnal and semidiurnal variations of both atmospheric pressure and radon concentration in soil gases is shown to be useful for estimating soil gas transport parameters. The two daily-cycle peaks at 12- and 24-hour periods in the Power Spectral Density (PSD) of atmospheric pressure seem to be present everywhere on Earth's surface, and it is the effect of these regular pressure variations on the radon concentration in soil gases that makes it possible to determine three soil gas transport parameters which can be used to estimate real gas velocity; i.e. tortuosity τ, the ratio k/n between intrinsic permeability and effective porosity (that part of porosity involved in gas transport), and the pressure gradient α. The parameters k and n can be determined independently if the gas flux at the surface is measured at the same time. The method is robust, representative, and accurate: since it allows reliable estimation of transport parameters, it can provide relevant information about the depth of the radon source and the time it takes for information to reach the surface when radon bursts occur at depth. Radon is an appropriate soil gas tracer because it exists in all soils. Moreover, the measurement of radon concentration requires only passive sensors that do not hamper the rising gas column. Gas flux data obtained in Andalusia, Spain, in connection with mineral exploration are processed as examples. Determining the complete set of transport parameters helps in the interpretation of recorded radon outbursts, which are found to be correlated with regional seismic activity.

  15. Simulation of the steady-state transport of radon from soil into houses with basements under constant negative pressure

    Energy Technology Data Exchange (ETDEWEB)

    de Oliveira Loureiro, C.

    1987-05-01

    A theoretical model was developed to simulate this phenomenon, under some specific assumptions. The model simulates: the generation and decay of radon within the soil; its transport throughout the soil due to diffusion and convection induced by the pressure disturbance applied at a crack in the basement; its entrance into the house through the crack; and the resultant indoor radon concentration. The most important assumptions adopted in the model were: a steady-state condition; a house with a basement; a geometrically well-defined crack at the wall-floor joint in the basement; and a constant negative pressure applied at the crack in relation to the outside atmospheric pressure. Two three-dimensional finite-difference computer programs were written to solve the mathematical equations of the model. The first program, called PRESSU, was used to calculate: the pressure distribution within the soil as a result of the applied disturbance pressure at the crack; and the resultant velocity distribution of the soil gas throughout the soil matrix. The second program, called MASTRA, was used to: solve the radon mass-transport equation, and to calculate the concentration distribution of radon in the soil gas within the whole soil; and to calculate the entry rate of radon through the crack into the basement, and the final indoor radon concentration. A parametric sensitivity analysis performed on the model, revealed several features of the mechanisms involved in the transport of radon into the house. 84 refs., 66 figs., 16 tabs.

  16. Radon generation and transport in and around a gold mine tailings dam in South Africa

    Energy Technology Data Exchange (ETDEWEB)

    Speelman, W.J.; Lindsay, R. [Western Cape Univ., Dept. of Physics (South Africa); Newman, R.T. [IThemba LABS, Somerset West (South Africa); Meijer, R.J. de [Nuclear Geophysics Division (NGD), KVI, Rijksuniversiteit Groningen (Netherlands)

    2006-07-01

    Naturally Occurring Radioactive Material (N.O.R.M.) occurs in most soil and rock, and by mining and mineral processing, some of the radionuclides are significantly enhanced. An in-situ gamma-ray detector called M.E.D.U.S.A., has been used to produce a map of relative activity concentrations in a gold mine tailings dam on the Witwatersrand in South Africa. A CsI(Na) scintillation detector is used in this system. M.E.D.U.S.A. spectra obtained from the survey were analyzed using the Full-Spectrum Analysis (F.S.A.) procedure to compute the {sup 40}K, {sup 238}U and {sup 232}Th activity concentrations. The activity concentrations are used with global positioning data (G.P.S.) to produce the concentration maps. A hyper-pure germanium gamma-ray detector (Hp Ge) was used to measure gamma-rays from the naturally occurring nuclides for soil samples taken at different points on the site to calibrate the M.E.D.U.S.A. system. Radon soil gas measurements were performed at certain points on the mine tailings with a continuous radon monitor; R.A.D.7, and emanation coefficients were measured with electret technology. These parameters have been combined with the activity concentrations to obtain an average radon exhalation rate of about 0.1 Bq.m{sup -2}.s{sup -1} (with an uncertainty of about 20%) from the tailings dam. The purpose of the study is to also review and develop a mathematical model for radon activity concentration predictions in gold mine dumps. (authors)

  17. Radon-222 and gamma ray levels associated with the collection, processing, transmission, and utilization of natural gas.

    Science.gov (United States)

    van Netten, C; Kan, K; Anderson, J; Morley, D

    1998-09-01

    The natural gas industry in British Columbia was investigated for exposure to radioactive contaminants such as radon-222 and lead-210. Radon activity associated with the gathering system ranged from 7-921 Bq/m3. The pipelines to the processing facility contained sludge that had a mean lead-210 activity of 0.494 Bq/g (0.379 standard deviation [SD]) and a mean radium-226 activity of 0.417 (0.398 SD). Within the processing facility the highest levels of radon were associated with propane production streams, and activities as high as 4958 Bq/m3 were found. Equipment handling these streams was also found to have a buildup of scale with lead-210, radium-224, and radium-226 activity. The transmission of salable gas to the consumer indicated a decrease in radon activity that was slightly lower than the estimated radon activity based on the half-life of radon, the distance from the production facility, and the speed of gas transmission. The risk of radon exposure to the worker was deemed well below the guidelines and would be controlled more than adequately by means of the occupational standards for the natural gas components. Gamma ray exposure was also well below the occupational standards. Radon exposure to the consumer was virtually nonexistent in the Vancouver region from both natural gas and propane. Although this might not be the case for consumers of propane closer to the production facilities, its contribution is likely to be minimal.

  18. Atmospheric radionuclide transport model with radon postprocessor and SBG module. Model description version 2.8.0; ARTM. Atmosphaerisches Radionuklid-Transport-Modell mit Radon Postprozessor und SBG-Modul. Modellbeschreibung zu Version 2.8.0

    Energy Technology Data Exchange (ETDEWEB)

    Richter, Cornelia; Sogalla, Martin; Thielen, Harald; Martens, Reinhard

    2015-04-20

    The study on the atmospheric radionuclide transport model with radon postprocessor and SBG module (model description version 2.8.0) covers the following issues: determination of emissions, radioactive decay, atmospheric dispersion calculation for radioactive gases, atmospheric dispersion calculation for radioactive dusts, determination of the gamma cloud radiation (gamma submersion), terrain roughness, effective source height, calculation area and model points, geographic reference systems and coordinate transformations, meteorological data, use of invalid meteorological data sets, consideration of statistical uncertainties, consideration of housings, consideration of bumpiness, consideration of terrain roughness, use of frequency distributions of the hourly dispersion situation, consideration of the vegetation period (summer), the radon post processor radon.exe, the SBG module, modeling of wind fields, shading settings.

  19. Preliminary Study for 3D Radon Distribution Modelling in the Room

    Energy Technology Data Exchange (ETDEWEB)

    Lee, ChoongWie; Kim, HeeReyoung [UNIST, Ulsan (Korea, Republic of)

    2016-10-15

    Radon exists in the form of noble gas, which comes from decay of {sup 238}U, becoming stable {sup 206}Pb going through 4 alpha and 4 beta decays. If this process occurred in human body after inhalation, lung could be damaged by interaction with these radiations causing lung cancer. Most radon in indoor air comes from soil (85 - 97%) through crack of the wall but it also came from wall (2 - 5%) itself in home. Due to its hazardous and unpredictable characteristic, radon became one of the concerning nuclides in indoor air. Hence, the number of survey and research about radon has been increased. Although accurate radon measurement is important to evaluate health risk, it is hard to actually achieve because radon is affected by many conditions, where its concentration can vary easily. Moreover, radon concentration can vary according to the height because of density of radon in the spatial aspect. 3D distribution modelling in the room of radon with aerodynamic features and sources variations was carried out to find average and maximum radon concentration. 3D radon distribution in the room would be find through this computational analysis and it is thought to be possible to correct measured radon concentration with spatial variation to fit the height of nose where inhalation occur. The methodological concept for 3D modelling was set up to solve transport equation for radon behavior by using computational fluid dynamics (CFD) software such as FLUENT.

  20. Radon exhalation measurements for environmental and geophysics study

    Science.gov (United States)

    Immé, G.; Catalano, R.; Mangano, G.; Morelli, D.

    2014-02-01

    Transport of radon through materials is a process strongly influenced by several parameters characterizing the materials themselves, such as porosity, permeability, grain size, content of radionuclides and diffusion coefficient of this gas through the interstitial pores and/or fractures of material. In order to enlighten more on the radon transport mechanisms, we are carrying out a systematic study on both in-soil radon measurements and laboratory analysis. Laboratory measurements are carried out on different types of samples from geologically different sites in the East Sicily (Italy), to measure the exhalation rate of radon at different controlled physical conditions, varying the parameters of porosity and grain size, content of radio, in order to characterize the dependence of the process of radon transport by these parameters.We report in particular preliminary results of our study on radionuclide content and on the radon exhalation rate from building materials used in Mt. Etna and in the Hyblean Plateau villages.This study is important from the radioprotection point of view and could represent a contribution to better define the transport process of radon through fractured media to clarify on correlation between radon concentration and geodynamical, volcanic and tectonic, events.

  1. The radon; Le radon

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-07-01

    This booklet is intended to answer briefly the most important questions about the nature and sources of radon, its pathways from environment to organism, as well as the ways to minimize its concentration in the habitat's atmosphere. The radon is a naturally appearing radioactive gas, produced through the decay of uranium and radium present in the terrestrial crust. It can be found everywhere on the planet's surface and it is emitted particularly from the granite and volcanic underground rocks as well as from certain construction materials. It is one of the agents producing pulmonary cancer, although not so dangerous as the tobacco is. The following items are elaborated in this booklet: - the place of radon in the average exposure to ionizing radiations of the French population; - the risk; - the radon in the environment (the meteorological conditions, the nature of the rocks); - radon in dwellings (radon measurements in the French dwellings, the entrance pathways of radon, the dependence of radon concentration on the profession and way of life of the inhabitants); - radon measurements; - how to reduce the radon concentration in dwellings.

  2. Simulation of the Steady-State Transport of Radon from Oil intoHouses with Basements under Constant Negative Pressure

    Energy Technology Data Exchange (ETDEWEB)

    de Oliveira Loureiro, Celso [Univ. of California, Berkeley, CA (United States)

    1987-05-01

    Normal conditions in a house can produce negative pressures as high as 20 Pa relative to the outside. This underpressure, which is a maximum at the base of the house (the basement, for instance), can induce a flow of soil gas into the house, through cracks or any other openings in the understructure of the building. Radon (Rn-222), which is produced in the soil and mixed in the soil gas, can then be transported into the house through a complex combination of molecular diffusion and forced convection. In many of the cases where high levels of indoor radon concentrations have been observed in houses, the soil gas has been concluded to be the main source.

  3. Use of radon for evaluation of atmospheric transport models: sensitivity to emissions

    Energy Technology Data Exchange (ETDEWEB)

    Gupta, Mohan L. [GEST/GSFC NASA, Greenbelt, MD (United States); Douglass, Anne R.; Kawa, S. Randolph [NASA GSFC, Greenbelt, MD (United States); Pawson, Steven [GEST/GSFC NASA, GMAO, Greenbelt, MD (United States)

    2004-11-01

    We present comparative analyses of atmospheric radon (Rn) distributions simulated using different emission scenarios and the observations. Results indicate that the model generally reproduces observed distributions of Rn but there are some biases in the model related to differences in large-scale and convective transport. Simulations presented here use an off-line three-dimensional chemical transport model driven by assimilated winds and two scenarios of Rn fluxes (atom/cm{sup 2}/s) from ice-free land surfaces: (A) globally uniform flux of 1.0 within {+-}60 deg and 0.5 within 60 deg N - 70 deg N and (B) uniform flux of 1.0 between 60 deg S and 30 deg N followed by a sharp linear decrease to 0.2 at 70 deg N. We considered an additional scenario (C) where Rn emissions for case A were uniformly reduced by 28%. Results show that case A overpredicts observed Rn distributions in both hemispheres. Simulated Northern Hemisphere Rn distributions from cases B and C compare better with the observations, but are not discernible from each other. In the Southern Hemisphere, surface Rn distributions from case C compare better with the observations. We performed a synoptic-scale source-receptor analysis for surface Rn to locate regions with ratios B/A and B/C less than 0.5. Considering the maximum uncertainty in regional Rn emissions of a factor of 2, our analysis indicates that additional measurements of surface Rn, particularly during April-October and north of 50 deg N over the Pacific as well as Atlantic regions, would make it possible to determine if the proposed latitude gradient in Rn emissions is superior to a uniform flux scenario.

  4. Use of Radon for Evaluation of Atmospheric Transport Models: Sensitivity to Emissions

    Science.gov (United States)

    Gupta, Mohan L.; Douglass, Anne R.; Kawa, S. Randolph; Pawson, Steven

    2004-01-01

    This paper presents comparative analyses of atmospheric radon (Rn) distributions simulated using different emission scenarios and the observations. Results indicate that the model generally reproduces observed distributions of Rn but there are some biases in the model related to differences in large-scale and convective transport. Simulations presented here use an off-line three-dimensional chemical transport model driven by assimilated winds and two scenarios of Rn fluxes (atom/cm s) from ice-free land surfaces: (A) globally uniform flux of 1.0, and (B) uniform flux of 1.0 between 60 deg. S and 30 deg. N followed by a sharp linear decrease to 0.2 at 70 deg. N. We considered an additional scenario (C) where Rn emissions for case A were uniformly reduced by 28%. Results show that case A overpredicts observed Rn distributions in both hemispheres. Simulated northern hemispheric (NH) Rn distributions from cases B and C compare better with the observations, but are not discernible from each other. In the southern hemisphere, surface Rn distributions from case C compare better with the observations. We performed a synoptic scale source-receptor analysis for surface Rn to locate regions with ratios B/A and B/C less than 0.5. Considering an uncertainty in regional Rn emissions of a factor of two, our analysis indicates that additional measurements of surface Rn particularly during April-October and north of 50 deg. N over the Pacific as well as Atlantic regions would make it possible to determine if the proposed latitude gradient in Rn emissions is superior to a uniform flux scenario.

  5. ERRICCA radon model intercomparison exercise

    DEFF Research Database (Denmark)

    Andersen, C.E.; Albarracín, D.; Csige, I.

    1999-01-01

    Numerical models based on finite-difference or finite-element methods are used by various research groups in studies of radon-222 transport through soil and building materials. Applications range from design of radon remediation systems to morefundamental studies of radon transport. To ascertain ......, still remain. All in all, it seems that the exercise has served its purpose and stimulated improvements relating to the quality of numerical modelling of radon transport. To maintain a high quality of modelling, it is recommendedthat additional exercises are carried out....

  6. Radon flux maps for the Netherlands and Europe using terrestrial gamma radiation derived from soil radionuclides

    NARCIS (Netherlands)

    Manohar, S.N.; Meijer, H.A.J.; Herber, M.A.

    2013-01-01

    Naturally occurring radioactive noble gas, radon (Rn-222) is a valuable tracer to study atmospheric processes and to validate global chemical transport models. However, the use of radon as a proxy in atmospheric and climate research is limited by the uncertainties in the magnitude and distribution

  7. Radon measurements aboard the Kuiper Airborne Observatory

    Science.gov (United States)

    Kritz, Mark A.; Rosner, Stefan W.

    1995-01-01

    We have carried out three (piggyback) radon-related projects aboard the KAO. The first, which was limited to upper tropospheric measurements while in level flight, revealed the systematic occurrence of unexpectedly high radon concentrations in this region of the atmosphere. The second project was an instrument development project, which led to the installation of an automatic radon measurement system aboard the NASA ER-2 High Altitude Research Aircraft. In the third, we installed a new system capable of collecting samples during the normal climb and descent of the KAO. The results obtained in these projects have resulted in significant contributions to our knowledge of atmospheric transport processes, and are currently playing a key role in the validation of global circulation and transport models.

  8. CONTRIBUTION OF RADON FLOWS AND RADON SOURCES TO THE RADON CONCENTRATION IN A DWELLING

    NARCIS (Netherlands)

    DEMEIJER, RJ; STOOP, P; PUT, LW

    1992-01-01

    In this paper a model is presented for analysis of the radon concentrations in a compartment in terms of contributions from transport by flows of air between compartments and from radon sources in the compartment. Measurements were made to study the effect of increased natural ventilation of the

  9. Inferring coastal processes from regional-scale mapping of {sup 222}Radon and salinity: examples from the Great Barrier Reef, Australia

    Energy Technology Data Exchange (ETDEWEB)

    Stieglitz, Thomas C., E-mail: thomas.stieglitz@jcu.edu.a [AIMS-JCU, Townsville (Australia); Australian Institute of Marine Science, PMB NO 3, Townsville QLD 4810 (Australia); School of Engineering and Physical Sciences, James Cook University, Townsville QLD 4811 (Australia); Cook, Peter G., E-mail: peter.g.cook@csiro.a [CSIRO Land and Water, Private Bag 2, Glen Osmond SA 5064 (Australia); Burnett, William C., E-mail: wburnett@mailer.fsu.ed [Department of Oceanography, Florida State University, Tallahassee, FL 32306 (United States)

    2010-07-15

    The radon isotope {sup 222}Rn and salinity in coastal surface water were mapped on regional scales, to improve the understanding of coastal processes and their spatial variability. Radon was measured with a surface-towed, continuously recording multi-detector setup on a moving vessel. Numerous processes and locations of land-ocean interaction along the Central Great Barrier Reef coastline were identified and interpreted based on the data collected. These included riverine fluxes, terrestrially-derived fresh submarine groundwater discharge (SGD) and the tidal pumping of seawater through mangrove forests. Based on variations in the relationship of the tracers radon and salinity, some aspects of regional freshwater inputs to the coastal zone and to estuaries could be assessed. Concurrent mapping of radon and salinity allowed an efficient qualitative assessment of land-ocean interaction on various spatial and temporal scales, indicating that such surveys on coastal scales can be a useful tool to obtain an overview of SGD locations and processes.

  10. Reducing Radon in Schools: A Team Approach.

    Science.gov (United States)

    Ligman, Bryan K.; Fisher, Eugene J.

    This document presents the process of radon diagnostics and mitigation in schools to help educators determine the best way to reduce elevated radon levels found in a school. The guidebook is designed to guide school leaders through the process of measuring radon levels, selecting the best mitigation strategy, and directing the efforts of a…

  11. Radon transport model into a porous ground layer of finite capacity

    Science.gov (United States)

    Parovik, Roman

    2017-10-01

    The model of radon transfer is considered in a porous ground layer of finite power. With the help of the Laplace integral transformation, a numerical solution of this model is obtained which is based on the construction of a generalized quadrature formula of the highest degree of accuracy for the transition to the original - the function of solving this problem. The calculated curves are constructed and investigated depending on the diffusion and advection coefficients.The work was a mathematical model that describes the effect of the sliding attachment (stick-slip), taking into account hereditarity. This model can be regarded as a mechanical model of earthquake preparation. For such a model was proposed explicit finite- difference scheme, on which were built the waveform and phase trajectories hereditarity effect of stick-slip.

  12. Scopingsreport Radon

    NARCIS (Netherlands)

    Blaauboer RO; Vaas LH; Hesse JM; Slooff W

    1989-01-01

    Dit scopingsrapport vormt een onderdeel van de voorbereiding tot het opstellen van het basisdocument radon. Het doel van dit rapport is het algemene kennisniveau van de deelnemers aan de scopingsbijeenkomst aangaande radon op eenzelfde peil te brengen en discussie- en beslispunten inzake de

  13. Sensitivity of Global Modeling Initiative chemistry and transport model simulations of radon-222 and lead-210 to input meteorological data

    Directory of Open Access Journals (Sweden)

    D. B. Considine

    2005-01-01

    Full Text Available We have used the Global Modeling Initiative chemistry and transport model to simulate the radionuclides radon-222 and lead-210 using three different sets of input meteorological information: 1. Output from the Goddard Space Flight Center Global Modeling and Assimilation Office GEOS-STRAT assimilation; 2. Output from the Goddard Institute for Space Studies GISS II' general circulation model; and 3. Output from the National Center for Atmospheric Research MACCM3 general circulation model. We intercompare these simulations with observations to determine the variability resulting from the different meteorological data used to drive the model, and to assess the agreement of the simulations with observations at the surface and in the upper troposphere/lower stratosphere region. The observational datasets we use are primarily climatologies developed from multiple years of observations. In the upper troposphere/lower stratosphere region, climatological distributions of lead-210 were constructed from ~25 years of aircraft and balloon observations compiled into the US Environmental Measurements Laboratory RANDAB database. Taken as a whole, no simulation stands out as superior to the others. However, the simulation driven by the NCAR MACCM3 meteorological data compares better with lead-210 observations in the upper troposphere/lower stratosphere region. Comparisons of simulations made with and without convection show that the role played by convective transport and scavenging in the three simulations differs substantially. These differences may have implications for evaluation of the importance of very short-lived halogen-containing species on stratospheric halogen budgets.

  14. Variability of Atmospheric Radon-222 and Secondary Aerosol Components in Accordance with Air Mass Transport Pathways at Jeju Island, Korea, during 2011-2014

    Energy Technology Data Exchange (ETDEWEB)

    Bu, Jun-Oh; Song, Jung-Min; Kim, Won-Hyung; Kang, Chang-Hee [Jeju National University, Jeju (Korea, Republic of); Chambers, Scott D.; Williams, Alastair G. [Australian Nuclear Science and Technology Organisation, Kirrawee DC (Australia); Lee, Chulkyu [Korea Meteorological Administration, Seoul (Korea, Republic of)

    2016-06-15

    Real-time monitoring of hourly atmospheric Radon-222 concentration and three daily monitoring of the secondary aerosol components of PM{sub 10} were performed throughout 2011-2014 at Gosan station, Jeju Island, in order to characterize their background levels and temporal variation. The annual mean radon and PM{sub 10} mass concentrations were 2326 ± 1198 mBq/m{sup 3} and 37.1 ± 19.5 μg/m{sup 3}, respectively. Based on cluster analyses of air mass back trajectories, the frequencies of air masses originating from continental China, the Korean Peninsula, and North Pacific Ocean routes were 53, 28, and 19%, respectively. When the air masses were transported to Jeju Island from continental China, the concentrations of radon and secondary aerosol components (nss-SO{sub 4}{sup 2-}, NO{sub 3}{sup -}, NH{sub 4}{sup +}) were relatively high: 2577 mBq/m{sup 3} and 14.4 μg/m{sup 3}, respectively. In cases when the air masses have moved from the Korean Peninsula, the corresponding concentrations were 2247 mBq/m{sup 3} and 11.4 μg/m{sup 3}, respectively. On the other hand, when the air masses came from the North Pacific Ocean, their radon and secondary aerosol concentrations decreased much further, 1372 mBq/m{sup 3} and 10.5 μg/m{sup 3}, respectively. Consequently, the variability of atmospheric radon concentrations at Gosan station might be characterized by synoptic changes in air mass fetch as well as diurnal changes in atmospheric mixing depth.

  15. Crew Transportation Technical Management Processes

    Science.gov (United States)

    Mckinnie, John M. (Compiler); Lueders, Kathryn L. (Compiler)

    2013-01-01

    Under the guidance of processes provided by Crew Transportation Plan (CCT-PLN-1100), this document, with its sister documents, International Space Station (ISS) Crew Transportation and Services Requirements Document (CCT-REQ-1130), Crew Transportation Technical Standards and Design Evaluation Criteria (CCT-STD-1140), Crew Transportation Operations Standards (CCT STD-1150), and ISS to Commercial Orbital Transportation Services Interface Requirements Document (SSP 50808), provides the basis for a National Aeronautics and Space Administration (NASA) certification for services to the ISS for the Commercial Provider. When NASA Crew Transportation System (CTS) certification is achieved for ISS transportation, the Commercial Provider will be eligible to provide services to and from the ISS during the services phase.

  16. Radon as geological tracer

    Energy Technology Data Exchange (ETDEWEB)

    Lacerda, T.; Anjos, R.M. [Universidade Federal Fluminense (UFF), Niteroi, RJ (Brazil). Inst. de Fisica; Valladares, D.L.; Rizzotto, M.; Velasco, H.; Ayub, J. Juri [Universidad Nacional de San Luis (Argentina). Inst. de Matematica Aplicada San Luis (IMASL); Silva, A.A.R. da; Yoshimura, E.M. [Universidade de Sao Paulo (IF/USP), SP (Brazil). Inst. de Fisica

    2012-07-01

    Full text: This work presents measurements of {sup 222}Rn levels performed in La Carolina gold mine and Los Condores tungsten mine at the province of San Luis, Argentina, today used for tourist visitation, and can evaluate the potential use of such radioactive noble gas as tracer or marker for geological processes in underground environments. By concentrations of {sup 40}K, {sup 232}Th and {sup 23}'8U were also measured in the walls of tunnels were determined the rocks mineral composition, what indicated that the mines have the same composition. In this sense, we used nuclear trace plastic detectors CR-39, gamma spectrometry of rock samples and Geiger-Muller (GM) monitors The patterns of radon gas transportation processes revealed that La Carolina could be interpreted through a model based on a radioactive gas confined into a single entrance tube, with constant cross section and air velocity. Los Condores, which has a second main entrance, could be interpreted through a model based on a radioactive gas confined into a two entrance tube, allowing a chimney effect for air circulation. The results showed the high potential of using {sup 222}Rn as a geological tracer. In what concerns the occupational hazard, in summer (time of more intense tourist activity in the mine) La Carolina presented a mean concentration of the radioactive noble gas that exceeds in four times the action level of 1,5 kBq m{sup -3} recommended by the International Commission of Radiological Protection (ICRP). The chimney effect shows the low mean concentration of radon in Los Condores. (author)

  17. Spatiotemporal variation of radon and carbon dioxide concentrations in an underground quarry: coupled processes of natural ventilation, barometric pumping and internal mixing.

    Science.gov (United States)

    Perrier, Frédéric; Richon, Patrick

    2010-04-01

    Radon-222 and carbon dioxide concentrations have been measured during several years at several points in the atmosphere of an underground limestone quarry located at a depth of 18 m in Vincennes, near Paris, France. Both concentrations showed a seasonal cycle. Radon concentration varied from 1200 to 2000 Bq m(-3) in summer to about 800-1400 Bq m(-3) in winter, indicating winter ventilation rates varying from 0.6 to 2.5 x 10(-6) s(-1). Carbon dioxide concentration varied from 0.9 to 1.0% in summer, to about 0.1-0.3% in winter. Radon concentration can be corrected for natural ventilation using temperature measurements. The obtained model also accounts for the measured seasonal variation of carbon dioxide. After correction, radon concentrations still exhibit significant temporal variation, mostly associated with the variation of atmospheric pressure, with coupling coefficients varying from -7 to -26 Bq m(-3) hPa(-1). This variation can be accounted for using a barometric pumping model, coupled with natural ventilation in winter, and including internal mixing as well. After correction, radon concentrations exhibit residual temporal variation, poorly correlated between different points, with standard deviations varying from 3 to 6%. This study shows that temporal variation of radon concentrations in underground cavities can be understood to a satisfactory level of detail using non-linear and time-dependent modelling. It is important to understand the temporal variation of radon concentrations and the limitations in their modelling to monitor the properties of natural or artificial underground settings, and to be able to assess the existence of new processes, for example associated with the preparatory phases of volcanic eruptions or earthquakes. Copyright 2009 Elsevier Ltd. All rights reserved.

  18. Processing of radon time series in underground environments: Implications for volcanic surveillance in the island of Tenerife, Canary Islands, Spain

    Energy Technology Data Exchange (ETDEWEB)

    Vinas, Ronaldo [Department of Soil Sciences and Geology, Faculty of Biology, Universidad de La Laguna, Av. Astrofisico Fransicso Sanchez s/n, 38206 Tenerife (Spain); Eff-Darwich, Antonio [Department of Soil Sciences and Geology, Faculty of Biology, Universidad de La Laguna, Av. Astrofisico Fransicso Sanchez s/n, 38206 Tenerife (Spain)]. E-mail: adarwich@ull.es; Soler, Vicente [Volcanological Station of the Canary Islands, IPNA-CSIC, 38206 La Laguna, Tenerife (Spain); Martin-Luis, Maria C. [Department of Soil Sciences and Geology, Faculty of Biology, Universidad de La Laguna, Av. Astrofisico Fransicso Sanchez s/n, 38206 Tenerife (Spain); Quesada, Maria L. [Department of Soil Sciences and Geology, Faculty of Biology, Universidad de La Laguna, Av. Astrofisico Fransicso Sanchez s/n, 38206 Tenerife (Spain); Nuez, Julio de la [Department of Soil Sciences and Geology, Faculty of Biology, Universidad de La Laguna, Av. Astrofisico Fransicso Sanchez s/n, 38206 Tenerife (Spain)

    2007-01-15

    The analysis of temporal and spatial variations in the flux of soil gases across the soil-air interface is a useful tool to study geo-dynamical processes associated with volcanic and/or seismic activity. However, many of these variations are induced by external variables, such as temperature, barometric pressure, rainfall and other meteorological variables. In an attempt to filter out non-endogenous variations in the emissions of gases, the optimal choice of the monitoring sites with numerical filtering techniques based on multi-variate and frequency domain analysis of the time series for gaseous emissions were combined, in the case of radon ({sup 222}Rn). Monitoring sites are located in underground galleries in the volcanic island of Tenerife, Canary Islands, Spain. Since the effect of wind, rainfall and temperature variations are very small inside galleries, a first natural filtering process of external parameters in the emissions of gases was achieved. This new approach has been successfully tested and as a result, the background level for radon emissions at various locations has been defined, by which correlations between gaseous emissions and the volcanic and/or seismic activity could be carried out.

  19. Evaluation of the uniformity of concentration of radon in a radon chamber.

    Science.gov (United States)

    Xiongjie, Zhang; Ye, Zhang; Yang, Liu; Bin, Tang

    2016-04-01

    In order to solve the problem that the evaluation results of the uniformity of concentration of radon in a radon chamber via various methods were difficult to compare, according to its statistical properties, a mathematical model was built to analyze the uniformity of concentration of radon; an evaluation method for the overall uniformity of concentration of radon was proposed on the basis of single-factor multi-group ANOVA, and a detection method for nonuniform points in a radon chamber was proposed on the basis of single-factor two-group t-test; an evaluation process of the uniformity of concentration of radon in a radon chamber was established. The proposed method was applied to evaluate the HD-6 small and medium-sized radon chambers and achieved good results. Copyright © 2016 Elsevier Ltd. All rights reserved.

  20. Radon monitoring and hazard prediction in Ireland

    Science.gov (United States)

    Elio, Javier; Crowley, Quentin; Scanlon, Ray; Hodgson, Jim; Cooper, Mark; Long, Stephanie

    2016-04-01

    Radon is a naturally occurring radioactive gas which forms as a decay product from uranium. It is the largest source of natural ionizing radiation affecting the global population. When radon is inhaled, its short-lived decay products can interact with lung tissue leading to DNA damage and development of lung cancer. Ireland has among the highest levels of radon in Europe and eighth highest of an OECD survey of 29 countries. Every year some two hundred and fifty cases of lung cancer in Ireland are linked to radon exposure. This new research project will build upon previous efforts of radon monitoring in Ireland to construct a high-resolution radon hazard map. This will be achieved using recently available high-resolution airborne gamma-ray spectrometry (radiometric) and soil geochemistry data (http://www.tellus.ie/), indoor radon concentrations (http://www.epa.ie/radiation), and new direct measurement of soil radon. In this regard, legacy indoor radon concentrations will be correlated with soil U and Th concentrations and other geogenic data. This is a new approach since the vast majority of countries with a national radon monitoring programme rely on indoor radon measurements, or have a spatially limited dataset of soil radon measurements. Careful attention will be given to areas where an indicative high radon hazard based on geogenic factors does not match high indoor radon concentrations. Where such areas exist, it may imply that some parameter(s) in the predictive model does not match that of the environment. These areas will be subjected to measurement of radon soil gas using a combination of time averaged (passive) and time dependant (active) measurements in order to better understand factors affecting production, transport and accumulation of radon in the natural environment. Such mapping of radon-prone areas will ultimately help to inform when prevention and remediation measures are necessary, reducing the radon exposure of the population. Therefore, given

  1. Relaxation processes in Aeolian transport

    Directory of Open Access Journals (Sweden)

    Selmani Houssem

    2017-01-01

    Full Text Available We investigate experimentally the relaxation process toward the equilibrium regime of saltation transport in the context of spatial inhomogeneous conditions. The relaxation length associated to this process is an important length in aeolian transport. This length stands for the distance needed for the particle flux to adapt to a change in flow conditions or in the boundary conditions at the bed. Predicting the value of this length under given conditions of transport remains an open and important issue. We conducted wind tunnel experiments to document the influence of the upstream particle flux and wind speed on the relaxation process toward the saturated transport state. In the absence of upstream particle flux, data show that the relaxation length is independent of the wind strength (except close to the threshold of transport. In contrast, in the case of a finite upstream flux, the relaxation length exhibits a clear increase with increasing air flow velocity. Moreover, in the latter the relaxation is clearly non-monotonic and presents an overshoot.

  2. Low-Cost Radon Reduction Pilot Study

    Energy Technology Data Exchange (ETDEWEB)

    Rose, William B. [Partnership for Advanced Residential Retrofit, Champaign, IL (United States); Francisco, Paul W. [Partnership for Advanced Residential Retrofit, Champaign, IL (United States); Merrin, Zachary [Partnership for Advanced Residential Retrofit, Champaign, IL (United States)

    2015-09-01

    The aim of the research was to conduct a primary scoping study on the impact of air sealing between the foundation and the living space on radon transport reduction across the foundation-living space floor assembly. Fifteen homes in the Champaign, Illinois area participated in the study. These homes were instrumented for hourly continuous radon measurements and simultaneous temperature and humidity the foundation was improved. However, this improved isolation did not lead to significant reductions in radon concentration in the living space. Other factors such as outdoor temperature were shown to have an impact on radon concentration.

  3. Transport processes at fluidic interfaces

    CERN Document Server

    Reusken, Arnold

    2017-01-01

    There are several physico-chemical processes that determine the behavior of multiphase fluid systems – e.g., the fluid dynamics in the different phases and the dynamics of the interface(s), mass transport between the fluids, adsorption effects at the interface, and transport of surfactants on the interface – and result in heterogeneous interface properties. In general, these processes are strongly coupled and local properties of the interface play a crucial role. A thorough understanding of the behavior of such complex flow problems must be based on physically sound mathematical models, which especially account for the local processes at the interface. This book presents recent findings on the rigorous derivation and mathematical analysis of such models and on the development of numerical methods for direct numerical simulations. Validation results are based on specifically designed experiments using high-resolution experimental techniques. A special feature of this book is its focus on an interdisciplina...

  4. Managing Radon in Schools

    Science.gov (United States)

    EPA recommends testing all schools for radon. As part of an effective IAQ management program, schools can take simple steps to test for radon and reduce risks to occupants if high radon levels are found.

  5. An analysis of the radioactive contamination due to radon in a granite processing plant and its decontamination by ventilation.

    Science.gov (United States)

    Dieguez-Elizondo, Pedro M; Gil-Lopez, Tomas; O'Donohoe, Paul G; Castejon-Navas, Juan; Galvez-Huerta, Miguel A

    2017-02-01

    This work focuses on studying concentration distribution of (222)Rn radioisotope in a granite processing plant. Using Computational Fluid Dynamic Techniques (CFD), the exposure of the workers to radiation was assessed and, in order to minimise this exposure, different decontamination scenarios using ventilation were analysed. Natural ventilation showed not sufficient to maintain radon concentration below acceptable limits, so a forced ventilation was used instead. Position of the granite blocks also revealed as a determining factor in the radioactive level distribution. Thus, a correct layout of the stored material and an adequate ventilation system can guarantee free of exposure to radiation zones within the studied workshop. This leads to a drastic fall in the exposure of the workers and consequently minimises their risk of developing aggressive illness like lung cancer. Copyright © 2016 Elsevier Ltd. All rights reserved.

  6. Radon Spectrum and Its Application for Small Moving Target Detection

    Science.gov (United States)

    2015-04-01

    UNCLASSIFIED UNCLASSIFIED Radon Spectrum and Its Application for Small Moving Target Detection Yunhan Dong National Security...coherent processing, the concept of a Radon spectrum that is a kind of normalised Radon transform is proposed and used for radar non-coherent detection...One advantage of using the Radon transform for non-coherent processing is that integration in all directions is considered, and hence range migration

  7. Interpreting the radon transform using Prolog

    Science.gov (United States)

    Batchelor, Bruce G.

    1992-03-01

    The Radon transform is an important method for identifying linear features in a digital image. However, the images which the Radon transform generates are complex and require intelligent interpretation, to identify lines in the input image correctly. This article describes how the images can be pre-processed to make the spots in the Radon transform image more easily identified and describes Prolog programs which can recognize constellations of points in the Radon transform image and thereby identify geometric figures within the input image.

  8. Methodology developed to make the Quebec indoor radon potential map

    Energy Technology Data Exchange (ETDEWEB)

    Drolet, Jean-Philippe, E-mail: jean-philippe.drolet@ete.inrs.ca [Institut national de la recherche scientifique, Eau Terre Environnement Research Centre (ETE-INRS), 490 de la Couronne, G1K 9A9 Quebec (Canada); Martel, Richard [Institut national de la recherche scientifique, Eau Terre Environnement Research Centre (ETE-INRS), 490 de la Couronne, G1K 9A9 Quebec (Canada); Poulin, Patrick [Institut national de santé publique du Québec (INSPQ), 945 avenue Wolfe, G1V 5B3 Quebec (Canada); Dessau, Jean-Claude [Agence de la santé et des services sociaux des Laurentides, 1000 rue Labelle, J7Z 5 N6 Saint-Jérome (Canada)

    2014-03-01

    This paper presents a relevant approach to predict the indoor radon potential based on the combination of the radiogeochemical data and the indoor radon measurements in the Quebec province territory (Canada). The Quebec ministry of health asked for such a map to identify the radon-prone areas to manage the risk for the population related to indoor radon exposure. Three radiogeochemical criteria including (1) equivalent uranium (eU) concentration from airborne surface gamma-ray surveys, (2) uranium concentration measurements in sediments, (3) bedrock and surficial geology were combined with 3082 basement radon concentration measurements to identify the radon-prone areas. It was shown that it is possible to determine thresholds for the three criteria that implied statistically significant different levels of radon potential using Kruskal–Wallis one way analyses of variance by ranks. The three discretized radiogeochemical datasets were combined into a total predicted radon potential that sampled 98% of the studied area. The combination process was also based on Kruskal–Wallis one way ANOVA. Four statistically significant different predicted radon potential levels were created: low, medium, high and very high. Respectively 10 and 13% of the dwellings exceed the Canadian radon guideline of 200 Bq/m{sup 3} in low and medium predicted radon potentials. These proportions rise up to 22 and 45% respectively for high and very high predicted radon potentials. This predictive map of indoor radon potential based on the radiogeochemical data was validated using a map of confirmed radon exposure in homes based on the basement radon measurements. It was shown that the map of predicted radon potential based on the radiogeochemical data was reliable to identify radon-prone areas even in zones where no indoor radon measurement exists. - Highlights: • 5 radiogeochemical datasets were used to map the geogenic indoor radon potential. • An indoor radon potential was determined for

  9. Radon in Estonian dwellings - Results from a National Radon Survey

    Energy Technology Data Exchange (ETDEWEB)

    Pahapill, Lia; Rulkov, Anne; Rajamaee, Raivo [Estonian Radiation Protection Centre (Kiirguskeskus), Tallinn (Spain); Aakerblom, Gustav [Swedish Radiation Protection Authority, Stockholm (Sweden)

    2003-10-01

    to be 60 Bq/m{sup 3}. Using the detriment factor given by ICRP, annually about 90 Estonians are expected to develop lung cancer due to exposure to radon in their homes. Most of them, about 75, are smokers, which are affected by the synergetic effect of the two carcinogens, smoking and radon. In Estonia the source of indoor radon is radon-containing soil air that is transported into the buildings from the ground. Building materials with enhanced radium concentrations are not known in Estonia. In this survey, the highest indoor radon concentrations have been found in the northern part of Estonia where uranium rich Dictyonema shale and uranium containing phosphorous Glauconite sandstone exist in the bedrock and as fragments in the soils. Radon concentrations higher than 400 Bq/m{sup 3} have also been measured in buildings situated in areas with karst formations. Areas with Dictyonema shale, Glauconite sandstone and karst are areas with a special risk for radon.

  10. Unexpected Daily Peaks in a Laboratory Simulation Experiment of Radon Signals

    Science.gov (United States)

    Bezaly, Orr Rose; Steinitz, Gideon; Israelevich, Peter; Kotlarsky, Peter; Piatibratova, Oksana; Malik, Uri; Asperil, Tal; Marco, Shmuel

    2017-04-01

    Radon is a noble radioactive gas of special interest in earth sciences due to both its unique chemical and physical properties and its natural abundance. The most stable isotope of radon, 222Rn, has a half-life of 3.823 days and is the only gas-phase atom in the 238U decay series. Radon could be considered as a possible tracer for tectonic and volcanic processes, yet the physical mechanisms that influence radon emanation from rock and transport are unclear. Our team strives to observe and analyse radon signals in monitored environments. Simulation of radon signals and investigation of their characteristics in laboratory experiments are conducted using radon in an enclosed chamber, termed "Enhanced Confined Mode" (ECM). An ECM experiment will be described; its arrangement comprises of two 222Rn sources of activity ˜105Bq each. The sources are connected in parallel via tube to a horizontal stainless steel cylinder (˜570cm3) that contains air at atmospheric pressure. Direct count rate measurements were performed using a NaI (2x2") gamma-ray scintillation detector aligned along the cylinder's axis, at one minute resolution, for over 60 days. Radon is supplied into the ECM chamber by diffusion and it disintegrates as it undergoes radioactive decay. A priori, a steady state of diffusion and radioactive decay rates is expected. However, our results show evident deviations from this expected steady state, namely fluctuations that are significant relative to the uncertainty in measurements. Predominant daily peaks characterise the data. Signal processing and analysis of these daily peaks will be presented.

  11. Transport processes in space plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Birn, J.; Elphic, R.C.; Feldman, W.C. [and others

    1997-08-01

    This is the final report of a three-year, Laboratory Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). The project represents a comprehensive research effort to study plasma and field transport processes relevant for solar-terrestrial interaction, involving the solar wind and imbedded magnetic field and plasma structures, the bow shock of the Earth`s magnetosphere and associated waves, the Earth`s magnetopause with imbedded flux rope structures and their connection with the Earth, plasma flow in the Earth`s magnetotail, and ionospheric beam/wave interactions. The focus of the work was on the interaction between plasma and magnetic and electric fields in the regions where different plasma populations exist adjacent to or superposed on each other. These are the regions of particularly dynamic plasma behavior, important for plasma and energy transport and rapid energy releases. The research addressed questions about how this interaction takes place, what waves, instabilities, and particle/field interactions are involved, how the penetration of plasma and energy through characteristic boundaries takes place, and how the characteristic properties of the plasmas and fields of the different populations influence each other on different spatial and temporal scales. These topics were investigated through combining efforts in the analysis of plasma and field data obtained through space missions with theory and computer simulations of the plasma behavior.

  12. Radon release from granites in south-west England

    CERN Document Server

    Poole, J

    2001-01-01

    accessory minerals. The enhancement of surface area was attributed to the alteration of feldspar to sericite. This has implications for the release of radon. It is thought that the large surface area provides a sink for the adsorption of radon, retaining it in the rock structure. This radon retention explains the paradoxical decline in radon release at small particle size/large specific surface area. Various mechanisms for radon emanation are discussed with reference to the Cornubian granites. It is shown that, based on the measured specific surface areas, inter-crystalline diffusion is a slow process and not a significant contributor to overall radon release (0.01%). Approximately 1% of the total radon produced can be attributed to direct recoil processes, based on the calculated recoil ranges (36 nm). The remainder was attributed to diffusion processes through crystal imperfections and dislocations. The microscopic scale model developed here is extended to the macroscopic scale through examination of the la...

  13. Natural radium and radon tracers to quantify water exchange and movement in reservoirs

    Science.gov (United States)

    Smith, Christopher G.; Baskaran, Mark

    2011-01-01

    Radon and radium isotopes are routinely used to quantify exchange rates between different hydrologic reservoirs. Since their recognition as oceanic tracers in the 1960s, both radon and radium have been used to examine processes such as air-sea exchange, deep oceanic mixing, benthic inputs, and many others. Recently, the application of radon-222 and the radium-quartet (223,224,226,228Ra) as coastal tracers has seen a revelation with the growing interest in coastal groundwater dynamics. The enrichment of these isotopes in benthic fluids including groundwater makes both radium and radon ideal tracers of coastal benthic processes (e.g. submarine groundwater discharge). In this chapter we review traditional and recent advances in the application of radon and radium isotopes to understand mixing and exchange between various hydrologic reservoirs, specifically: (1) atmosphere and ocean, (2) deep and shallow oceanic water masses, (3) coastal groundwater/benthic pore waters and surface ocean, and (4) aquifer-lakes. While the isotopes themselves and their distribution in the environment provide qualitative information about the exchange processes, it is mixing/exchange and transport models for these isotopes that provide specific quantitative information about these processes. Brief introductions of these models and mixing parameters are provided for both historical and more recent studies.

  14. Decadal radon cycles in a hot spring.

    Science.gov (United States)

    Yan, Rui; Woith, Heiko; Wang, Rongjiang; Wang, Guangcai

    2017-09-21

    A high-fidelity record covering nearly 40 years of water-dissolved radon from the hot spring site of BangLazhang (BLZ), Southwestern China is presented to study multi-year periodicities of radon. Ancillary observational data, i.e., water temperature, spring discharge rate, barometric pressure, combined with regional rainfall, galactic cosmic rays (GCR flux is modulated by solar wind and thus a proxy for solar activity) and regional seismicity from the same period are considered to identify potentially influencing factors controlling the changes in radon. Variations in radon concentration and ancillary observational data are studied using continuous Wavelet Power Spectrum (WPS), Wavelet Coherence (WTC), and Partial Wavelet Coherence (PWC). The results show that the long-period radon concentration is characterized by a quasi-decadal (8-11 years) cycle, matching well with the concurrent periodicity in water temperature, spring discharge rates and GCR. PWCs of radon, discharge rate and water temperature suggest that water temperature variations explain most of the coherent variability of radon and the discharge rate. We tentatively conclude that radon variations are mainly explained by variations in water temperature and spring discharge, which are modified and modulated by earthquakes and quasi-decadal variations of an unidentified process. The influence of solar activity on the decadal periodicity is discussed.

  15. Microfluidics and microscale transport processes

    CERN Document Server

    Chakraborty, Suman

    2012-01-01

    With an intense focus on micro- and nanotechnology from a fluidic perspective, this book details the research activities in key directions on both the theoretical and experimental fronts. As part of the IIT Kharagpur Research Monograph series, the text discusses topics such as capillary transport in microchannels, fluid friction and heat transfer in microchannels, electrokinetics, and interfacial transport in nanochannels. It also covers nanoparticle transport in colloidal suspensions, bubble generation in microfluidic channels, micro-heat pipe, the lattice Boltzmann method for phase changing

  16. Radon Guide for Tenants

    Science.gov (United States)

    This guide is for people who rent their apartments or houses. The guide explains what radon is, and how to find out if there is a radon problem in your home. The guide also talks about what you can do if there are high radon levels in your home.

  17. Radon exhalation rates corrected for leakage and back diffusion – Evaluation of radon chambers and radon sources with application to ceramic tile

    Directory of Open Access Journals (Sweden)

    M. Abo-Elmagd

    2014-10-01

    Full Text Available The natural radon decay, leakage and back diffusion are the main removal processes of radon from its container. Ignoring these processes leads to underestimate the measured value of radon related parameters like exhalation rate and radium content. This work is aimed to evaluate two different radon chambers through determining their leakage rate λv and evaluation of radon source by determine its back diffusion rate λb inside the evaluated radon chambers as well as a small sealed cup. Two different methods are adapted for measuring both the leakage rate and the back diffusion rate. The leakage rate can be determined from the initial slope of the radon decay curve or from the exponential fitting of the whole decay curve. This can be achieved if a continuous monitoring of radon concentration inside the chamber is available. Also, the back diffusion rate is measured by sealing the radon source in the chamber and used the initial slope of the buildup curve to determine λb and therefore the exhalation rate of the source. This method was compared with simple equation for λb based on the ratio of the source to the chamber volume. The obtained results are applied to ceramic tile as an important radon source in homes. The measurement is targeted the ceramic glaze before and after firing as well as the obtained tile after adhere the glaze on the tile main body. Also, six different tile brands from Egyptian market are subjected to the study for comparison.

  18. Transport processes of the legume symbiosome membrane

    Directory of Open Access Journals (Sweden)

    Victoria C Clarke

    2014-12-01

    Full Text Available The symbiosome membrane (SM is a physical barrier between the host plant and nitrogen-fixing bacteria in the legume-rhizobium symbiosis, and represents a regulated interface for the movement of solutes between the symbionts that is under plant control. The primary nutrient exchange across the SM is the transport of a carbon energy source from plant to bacteroid in exchange for fixed nitrogen. At a biochemical level two channels have been implicated in movement of fixed nitrogen across the SM and a uniporter that transports monovalent dicarboxylate ions has been characterized that would transport fixed carbon. The aquaporin NOD26 may provide a channel for ammonia, but the genes encoding the other transporters have not been identified. Transport of several other solutes, including calcium and potassium, have been demonstrated in isolated symbiosomes, and genes encoding transport systems for the movement of iron, nitrate, sulfate and zinc in nodules have been identified. However, definitively matching transport activities with these genes has proved difficult and many further transport processes are expected on the SM to facilitate the movement of nutrients between the symbionts. Recently, work detailing the SM proteome in soybean has been completed, contributing significantly to the database of known SM proteins. This represents a valuable resource for the identification of transporter protein candidates, some of which may correspond to transport processes previously described, or to novel transport systems in the symbiosis. Putative transporters identified from the proteome include homologues of transporters of sulfate, calcium, peptides and various metal ions. Here we review current knowledge of transport processes of the SM and discuss the requirements for additional transport routes of other nutrients exchanged in the symbiosis, with a focus on transport systems identified through the soybean SM proteome.

  19. Surface transport processes in charged porous media.

    Science.gov (United States)

    Gabitto, Jorge; Tsouris, Costas

    2017-07-15

    Surface transport processes are very important in chemistry, colloidal sciences, engineering, biology, and geophysics. Natural or externally produced charges on surfaces create electrical double layers (EDLs) at the solid-liquid interface. The existence of the EDLs produces several complex processes including bulk and surface transport of ions. In this work, a model is presented to simulate bulk and transport processes in homogeneous porous media comprising big pores. It is based on a theory for capacitive charging by ideally polarizable porous electrodes without Faradaic reactions or specific adsorption of ions. A volume averaging technique is used to derive the averaged transport equations in the limit of thin electrical double layers. Description of the EDL between the electrolyte solution and the charged wall is accomplished using the Gouy-Chapman-Stern (GCS) model. The surface transport terms enter into the average equations due to the use of boundary conditions for diffuse interfaces. Two extra surface transports terms appear in the closed average equations. One is a surface diffusion term equivalent to the transport process in non-charged porous media. The second surface transport term is a migration term unique to charged porous media. The effective bulk and transport parameters for isotropic porous media are calculated solving the corresponding closure problems. Copyright © 2017 Elsevier Inc. All rights reserved.

  20. Review of high-sensitivity Radon studies

    Science.gov (United States)

    Wojcik, M.; Zuzel, G.; Simgen, H.

    2017-10-01

    A challenge in many present cutting-edge particle physics experiments is the stringent requirements in terms of radioactive background. In peculiar, the prevention of Radon, a radioactive noble gas, which occurs from ambient air and it is also released by emanation from the omnipresent progenitor Radium. In this paper we review various high-sensitivity Radon detection techniques and approaches, applied in the experiments looking for rare nuclear processes happening at low energies. They allow to identify, quantitatively measure and finally suppress the numerous sources of Radon in the detectors’ components and plants.

  1. Indoor radon; Le radon dans les batiments

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-12-01

    The radon, a natural radioactive gas, is present almost everywhere on the earth's surface. It can be accumulated at high concentration in confined spaces (buildings, mines, etc). In the last decades many studies conducted in several countries showed that inhaling important amounts of radon rises the risk of lung cancer. Although, the radon is a naturally appearing radioactive source, it may be the subject of a human 'enhancement' of concentration. The increasing radon concentration in professional housing constitutes an example of enhanced natural radioactivity which can induce health risks on workers and public. Besides, the radon is present in the dwelling houses (the domestic radon). On 13 May 1996, the European Union Council issued the new EURATOM Instruction that establishes the basic standards of health protection of population and workers against the ionizing radiation hazards (Instruction 96/29/EURATOM, JOCE L-159 of 29 June 1996). This instruction does not apply to domestic radon but it is taken into consideration by another EURATOM document: the recommendation of the Commission 90/143/EURATOM of 21 February 1990 (JOCE L-80 of 27 March 1990). The present paper aims at establishing in accordance to European Union provisions the guidelines for radon risk management in working places, as well as in dwelling houses, where the implied risk is taken into account. This document does not deal with cases of high radon concentration on sites where fabrication, handling or storage of radium sources take place. These situations must be treated by special studies.

  2. Radon activity in the lower troposphere and its impact on ionization rate : a global estimate using different radon emissions

    NARCIS (Netherlands)

    Zhang, K. .; Feichter, J.; Kazil, J.; Wan, H.; Zhuo, W.; Griffiths, A. D.; Sartorius, H.; Zahorowski, W.; Ramonet, M.; Schmidt, Martina; Yver, C.; Neubert, R. E. M.; Brunke, E. -G.; Schulz, M.

    2011-01-01

    The radioactive decay of radon and its progeny can lead to ionization of air molecules and consequently influence aerosol size distribution. In order to provide a global estimate of the radon-related ionization rate, we use the global atmospheric model ECHAM5 to simulate transport and decay

  3. Consumer's Guide to Radon Reduction

    Science.gov (United States)

    ... Protection Agency Search Search Radon Contact Us Share Consumer's Guide to Radon Reduction: How to Fix Your ... See EPA’s About PDF page to learn more. Consumer's Guide to Radon Reduction: How to Fix Your ...

  4. Transport processes in pea seed coats

    NARCIS (Netherlands)

    Dongen, Joost Thomas van

    2001-01-01

    The research described in this thesis concerns transport processes in coats of developing pea seeds. The scope of the investigation ranges from seed coat anatomy, via transport studies to the cloning of cDNA encoding proteinaceous membrane pores, and the heterologous expression of these

  5. Radon-Instrumentation; Radon-Instrumentacion

    Energy Technology Data Exchange (ETDEWEB)

    Moreno y Moreno, A. [Departamento de Apoyo en Ciencias Aplicadas, Benemerita Universidad Autonoma de Puebla, 4 Sur 104, Centro Historico 72000 Puebla (Mexico)

    2003-07-01

    The presentation of the active and passive methods for radon, their identification and measure, instrumentation and characteristics are the objectives of this work. Active detectors: Active Alpha Cam Continuous Air Monitor, Model 758 of Victoreen, Model CMR-510 Continuous Radon Monitor of the Signature Femto-Tech. Passive detectors: SSNTD track detectors in solids Measurement Using Charcoal Canisters, disk of activated coal deposited in a metallic box Electrets Methodology. (Author)

  6. Radon therapy; Radon in der Therapie

    Energy Technology Data Exchange (ETDEWEB)

    Spruck, Kaija [Technische Hochschule Mittelhessen, Giessen (Germany). Inst. fuer Medizinische Physik und Strahlenschutz

    2017-04-01

    Radon therapies are used since more than 100 years in human medicine. Today this method is controversially discussed due to the possible increase of ionizing radiation induced tumor risk. Although the exact mode of biological radiation effect on the cell level is still not known new studies show the efficiency of the radon therapy without side effect for instance for rheumatic/inflammatory or respiratory disorders.

  7. YAPILARDA RADON FENOMENY

    OpenAIRE

    OZAN, Sadik Sezgin; EKİNCİ, Cevdet Emin

    2011-01-01

    Bu çaly?mada, yapylarda Radon konusu irdelenmi?tir. Radon, günlük hayatta sürekli maruz kaldy?ymyz radyasyonun yakla?yk %50'sini olu?turan ve topraktaki Uranyum'un bozunma zincirinin bir halkasy olan renksiz, kokusuz ve duyu organlaryyla algylanamayan radyoaktif bir gazdyr. Kayaçlardaki Uranyumun bozunmasy sonucu ortaya çykan Radon gazy, difüzyon yoluyla topra?a, oradan da atmosfere veya ortama yayylmaktadyr. Gazyn birikmesiyle, Radon yo?unlu?u kapaly mekânlarda veya iyi havalandyrylmayan yer...

  8. YAPILARDA RADON FENOMENY

    OpenAIRE

    OZAN, Sadik Sezgin; EKİNCİ, Cevdet Emin

    2011-01-01

    Bu çaly?mada, yapylarda Radon konusu irdelenmi?tir. Radon, günlük hayatta sürekli maruz kaldy?ymyz radyasyonun yakla?yk %50'sini olu?turan ve topraktaki Uranyum'un bozunma zincirinin bir halkasy olan renksiz, kokusuz ve duyu organlaryyla algylanamayan radyoaktif bir gazdyr. Kayaçlardaki Uranyumun bozunmasy sonucu ortaya çykan Radon gazy, difüzyon yoluyla topra?a, oradan da atmosfere veya ortama yayylmaktadyr. Gazyn birikmesiyle, Radon yo?unlu?u kapaly mekânlarda veya iyi havalandyry...

  9. Assessment of radon equilibrium factor from distribution parameters of simultaneous radon and radon progeny measurements.

    Science.gov (United States)

    Chen, Jing; Marro, Leonora

    2011-11-01

    In Canada, a radon and radon progeny survey was carried out in the 1970s in 19 cities. To the authors' knowledge, this is the only large survey of simultaneous radon and radon progeny measurements up to the present time. However, the survey was carried out for the purpose of establishing geographic variation of radon and radon progeny; therefore, radon equilibrium factors, F, were not assessed at that time. From the summary results of this large simultaneous radon and radon progeny survey, the characteristics of radon equilibrium factor were assessed. The average F factor assessed from this survey in 12,576 houses is 0.54. The current assessment may indicate that the typical F value of 0.4 recommended by the United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR), and the International Commission on Radiological Protection (ICRP) could lead to a downward bias in the estimation of radon doses to the lung.

  10. Characterization of the radon source in North-Central Florida. Final report part 1 -- Final project report; Final report part 2 -- Technical report

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-12-01

    This report contains two separate parts: Characterization of the Radon Source in North-Central Florida (final report part 1 -- final project report); and Characterization of the Radon Source in North-Central Florida (technical report). The objectives were to characterize the radon 222 source in a region having a demonstrated elevated indoor radon potential and having geology, lithology, and climate that are different from those in other regions of the U.S. where radon is being studied. Radon availability and transport in this region were described. Approaches for predicting the radon potential of lands in this region were developed.

  11. Radon exposure in abandoned metalliferous mines of South America

    Energy Technology Data Exchange (ETDEWEB)

    Silva, A.A.R. da; Umisedo, N.; Yoshimura, E.M. [Universidade de Sao Paulo (IF/USP), SP (Brazil). Inst. de Fisica. Lab. de Dosimetria; Anjos, R.M. [Universidade Federal Fluminense (LARA/UFF), Niteroi, RJ (Brazil). Inst. de Fisica. Lab. de Radioecologia; Valladares, D.L.; Velasco, H.; Rizzotto, M. [Universidad Nacional de San Luis (UNSL) (Argentina). Inst. de Matematica Aplicada San Luis

    2011-07-01

    Since the days of the Spanish and Portuguese conquerors, South America has been closely associated with the metalliferous ore mining. Gold, silver, tin, lead, tungsten, nickel, copper, and palladium ores have been explored over the last centuries. In addition, there has also been the development and promotion of other economic activities related to mining, as the underground mine tourism. A few works have been published on radon levels in the South American mining. In this study, we investigated the radon transport process and its health hazard in two exhausted and abandoned mines in San Luis Province, Argentina. These mines were chosen because they have different physical configurations in their cavities, features which can affect the air flow patterns and radon concentrations. La Carolina gold mine (32 deg 48' 0'' S, 66 deg 60' 0'' W) is currently a blind end system, corresponding to a horizontal excavation into the side of a mountain, with only a main adit. Los Condores wolfram mine (32 deg 33' 25'' S, 65 deg 15' 20'' W) is also a horizontal excavation into the side of a mountain, but has a vertical output (a shaft) at the end of the main gallery. Three different experimental methodologies were used. Radon concentration measurements were performed by CR-39 nuclear track detectors. The distribution of natural radionuclide activities ({sup 40}K, {sup 232}Th and {sup 238}U) was determined from rock samples collected along their main adits, using in laboratory gamma-ray spectrometry. The external gamma dose rate was evaluated using thermoluminescent dosimeters and a portable survey meter. The values for the {sup 222}Rn concentration ranged from 0.43 {+-} 0.04 to 1.48 {+-} 0.12 kBq/m{sup 3} in the Los Condores wolfram mine and from 1.8 {+-} 0.1 to 6.0{+-}0.5 kBq/m{sup 3} in the La Carolina gold mine, indicating that, in this mine, the radon levels exceed up to four times the action level of 1.5 kBq/m{sup 3

  12. Health Risk of Radon

    Science.gov (United States)

    ... encouraged by WHO’s attention to this important public health issue. "Radon poses an easily reducible health risk to ... and Toxics Environmental Information by Location Greener Living Health Land, Waste, and Cleanup Lead Mold Pesticides Radon Science Water A-Z Index Laws & ...

  13. MODEL RADIOACTIVE RADON DECAY

    Directory of Open Access Journals (Sweden)

    R.I. Parovik

    2012-06-01

    Full Text Available In a model of radioactive decay of radon in the sample (222Rn. The model assumes that the probability of the decay of radon and its half-life depends on the fractal properties of the geological environment. The dependencies of the decay parameters of the fractal dimension of the medium.

  14. Radon: Not so Noble

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 5; Issue 7. Radon: Not so Noble-Radon in the Environment and Associated Health Problems. Deepanjan Majumdar. General Article Volume 5 Issue 7 July 2000 pp 44-55. Fulltext. Click here to view fulltext PDF. Permanent link:

  15. LARGE BUILDING RADON MANUAL

    Science.gov (United States)

    The report summarizes information on how bilding systems -- especially the heating, ventilating, and air-conditioning (HVAC) system -- inclurence radon entry into large buildings and can be used to mitigate radon problems. It addresses the fundamentals of large building HVAC syst...

  16. Radon: Not so Noble

    Indian Academy of Sciences (India)

    electronic configuration. [ 5S25p65d106s26p6]. Deepanjan Majumdar. Radon is a radioactive noble gas that occurs naturally but becomes an environmental hazard when it remains con- centrated in enclosed places .... public water supplies. Rivers carry .... relationship between cancer incidence and radon exposure has.

  17. Transport processes in space physics and astrophysics

    CERN Document Server

    Zank, Gary P

    2014-01-01

    Transport Processes in Space Physics and Astrophysics' is aimed at graduate level students to provide the necessary mathematical and physics background to understand the transport of gases, charged particle gases, energetic charged particles, turbulence, and radiation in an astrophysical and space physics context. Subjects emphasized in the work include collisional and collisionless processes in gases (neutral or plasma), analogous processes in turbulence fields and radiation fields, and allows for a simplified treatment of the statistical description of the system. A systematic study that addresses the common tools at a graduate level allows students to progress to a point where they can begin their research in a variety of fields within space physics and astrophysics. This book is for graduate students who expect to complete their research in an area of plasma space physics or plasma astrophysics. By providing a broad synthesis in several areas of transport theory and modeling, the work also benefits resear...

  18. Radon entry into a simple test structure

    DEFF Research Database (Denmark)

    Andersen, C.E.; Søgaard-Hansen, J.; Majborn, B.

    1992-01-01

    in the cylinder and in selected locations in the soil. In this paper, the test structure is described, and initial results concerning the transport of soil gas and radon under steady-state conditions are reported. It is found that the soil in the vicinity of the structure is partially depleted with respect......A simple test structure for studies of radon entry into houses has been constructed at a field site at Riso National Laboratory. It consists of a 40 1, stainless-steel cylinder placed in a 0.52 m deep quadratic excavation with a side length of 2.4 m. The excavation is lined with an airtight...

  19. TQM brings collaboration to patient transport process.

    Science.gov (United States)

    Houston, K L; Clute, C; Ryan-Crepin, K; Kimball, M; Matthews, R

    1994-10-01

    Total quality management (TQM) principles can be utilized to achieve successful outcomes of an interdepartmental problem-solving process prior to implementation of a TQM formal structure within an organization. Prior to implementation of the new process, patient transport time from nursing units to lab destination was calculated at 17.6 minutes; postimplementation, an institutional benchmark of 15.4 minutes has been set. The mechanisms utilized for development, implementation, and evaluation of a process improvement team is the focus of the article. The reader will be taken on a journey through an interdepartmental problem-solving process utilizing the TQM principles.

  20. Fractal Theory and Field Cover Experiments: Implications for the Fractal Characteristics and Radon Diffusion Behavior of Soils and Rocks.

    Science.gov (United States)

    Tan, Wanyu; Li, Yongmei; Tan, Kaixuan; Duan, Xianzhe; Liu, Dong; Liu, Zehua

    2016-12-01

    Radon diffusion and transport through different media is a complex process affected by many factors. In this study, the fractal theories and field covering experiments were used to study the fractal characteristics of particle size distribution (PSD) of six kinds of geotechnical materials (e.g., waste rock, sand, laterite, kaolin, mixture of sand and laterite, and mixture of waste rock and laterite) and their effects on radon diffusion. In addition, the radon diffusion coefficient and diffusion length were calculated. Moreover, new formulas for estimating diffusion coefficient and diffusion length functional of fractal dimension d of PSD were proposed. These results demonstrate the following points: (1) the fractal dimension d of the PSD can be used to characterize the property of soils and rocks in the studies of radon diffusion behavior; (2) the diffusion coefficient and diffusion length decrease with increasing fractal dimension of PSD; and (3) the effectiveness of final covers in reducing radon exhalation of uranium tailings impoundments can be evaluated on the basis of the fractal dimension of PSD of materials.

  1. Stochastic transport processes in discrete biological systems

    CERN Document Server

    Frehland, Eckart

    1982-01-01

    These notes are in part based on a course for advanced students in the applications of stochastic processes held in 1978 at the University of Konstanz. These notes contain the results of re­ cent studies on the stochastic description of ion transport through biological membranes. In particular, they serve as an introduction to an unified theory of fluctuations in complex biological transport systems. We emphasize that the subject of this volume is not to introduce the mathematics of stochastic processes but to present a field of theoretical biophysics in which stochastic methods are important. In the last years the study of membrane noise has become an important method in biophysics. Valuable information on the ion transport mechanisms in membranes can be obtained from noise analysis. A number of different processes such as the opening and closing of ion channels have been shown to be sources of the measured current or voltage fluctuations. Bio­ logical 'transport systems can be complex. For example, the tr...

  2. Transport processes of radiopharmaceuticals and -modulators

    Directory of Open Access Journals (Sweden)

    Langguth Peter

    2011-06-01

    Full Text Available Abstract Radiotherapy and radiology have been indispensable components in cancer care for many years. The detection limit of small tumor foci as well as the development of radio-resistance and severe side effects towards normal tissues led to the development of strategies to improve radio-diagnostic and -therapeutic approaches by pharmaceuticals. The term "radiopharmaceutical" has been used for drugs labeled with radioactive tracers for therapy or diagnosis. In addition, drugs have been described to sensitize tumor cells to radiotherapy (radiosensitizers or to protect normal tissues from detrimental effects of radiation (radioprotectors. The present review summarizes recent concepts on the transport of radiopharmaceuticals, radiosensitizers, and radioprotectors in cells and tissues, e.g. by ATP-binding cassette transporters such as P-glycoprotein. Strengths and weaknesses of current strategies to improve transport-based processes are discussed.

  3. Mesoscopic Modeling of Reactive Transport Processes

    Science.gov (United States)

    Kang, Q.; Chen, L.; Deng, H.

    2012-12-01

    Reactive transport processes involving precipitation and/or dissolution are pervasive in geochemical, biological and engineered systems. Typical examples include self-assembled patterns such as Liesegang rings or bands, cones of stalactites in limestones caves, biofilm growth in aqueous environment, formation of mineral deposits in boilers and heat exchangers, uptake of toxic metal ions from polluted water by calcium carbonate, and mineral trapping of CO2. Compared to experimental studies, a numerical approach enables a systematic study of the reaction kinetics, mass transport, and mechanisms of nucleation and crystal growth, and hence provides a detailed description of reactive transport processes. In this study, we enhance a previously developed lattice Boltzmann pore-scale model by taking into account the nucleation process, and develop a mesoscopic approach to simulate reactive transport processes involving precipitation and/or dissolution of solid phases. The model is then used to simulate the formation of Liesegang precipitation patterns and investigate the effects of gel on the morphology of the precipitates. It is shown that this model can capture the porous structures of the precipitates and can account for the effects of the gel concentration and material. A wide range of precipitation patterns is predicted under different gel concentrations, including regular bands, treelike patterns, and for the first time with numerical models, transition patterns from regular bands to treelike patterns. The model is also applied to study the effect of secondary precipitate on the dissolution of primary mineral. Several types of dissolution and precipitation processes are identified based on the morphology and structures of the precipitates and on the extent to which the precipitates affect the dissolution of the primary mineral. Finally the model is applied to study the formation of pseudomorph. It is demonstrated for the first time by numerical simulation that a

  4. [Patients' exposure to electromagnetic fields and radon in radon spas].

    Science.gov (United States)

    Politański, Piotr; Olszewski, Jerzy; Mamrot, Paweł; Mariańska, Mlagda; Zmyślony, Marek

    2014-01-01

    Many patients of physiotherapeutic facilities using therapeutic radon are also referred to other treatments involving the use of electromagnetic field (EMF). However, in the light of the theory of EMF influence on free radicals, it is still an open question whether, application of EMF shortly after the radon treatment may alter the biological effects of radon or EMF. The aim of the study was to determine how large is the group of patients exposed to radon and EMF in Poland, and how high is the exposure of these patients to analyzed factors. The results of the study are to be used in the future assessment of the combined effects of radon and EMF in radon spas. Based on the statistical data and interviews held in the major Polish radon spas, the analysis of treatment structure was performed and exposure to radon and EMF was assessed by measuring radon concentrations and characteristic values of exposure to EMF. More than 8000 people per year are subjected to combined exposure to radon and EMF. Significant differences were found between measured radon concentrations (they ranged from approximately 61 kBq/m3 for inhalations with inhaler to only 290 Bq/m3 for graduation towers, p = 0.049) and EMF intensities corresponded to those observed in hazardous and dangerous zones for occupational exposure. The results of the study showed significant differences between radon concentrations during various radon treatments. There is a need to develop clear and universal procedures for the application of radon or radon combined with EMF in radon spas. The effects of patients' exposure to radon, especially combined with EMF need to be further studied.

  5. Radon i danske lejeboliger

    DEFF Research Database (Denmark)

    Rasmussen, Torben Valdbjørn; Skytte Clausen, Louise

    I denne undersøgelse kortlægges radonindholdet i indeluften og det undersøges, hvordan indholdet af radon i indeluften er fordelt og spredes i en ejendom, og om det er muligt at pege på en bygningsdel eller en bygningskomponent som en spredningsvej for radon i boliger. Boligerne er lejeboliger og...... ligger i etageejendomme, kæde- og rækkehuse tilhørende bygningstyper opført fra 1850 og frem. De udvalgte ejendomme ligger i områder af landet, hvor der ved tidligere undersøgelser har vist sig at være en stor andel af huse med et højt indhold af radon i indeluften. Koncentrationen af radon er målt over...

  6. Radon in Schools

    Science.gov (United States)

    ... that the problem can be solved. EPA's national survey of schools produced some alarming results about concentrations in our children's classrooms. Public awareness must be raised about the hazards of radon ...

  7. ROE Radon Data

    Data.gov (United States)

    U.S. Environmental Protection Agency — The polygon dataset represents predicted indoor radon screening levels in counties across the United States. These data were provided by EPA’s Office of Radiation...

  8. Radon og boligen

    DEFF Research Database (Denmark)

    Rasmussen, Torben Valdbjørn

    Radon er en radioaktiv og sundhedsskadelig luftart, som ved indånding øger risikoen for lungekræft. Der er ingen dokumenteret nedre grænse for, hvornår radon er ufarligt. Derfor anbefales det, at man tilstræber et så lavt radonindhold i indeluften som muligt. Man kan hverken lugte, se, høre eller...... smage radon, så vil du vide, om du har radon i din bolig, må du måle radonindholdet i indeluften. Radon forekommer naturligt i jorden og kan suges ind sammen med jordluft, hvis der inde er et undertryk, og hvis konstruktionerne mod jord er utætte. Jordluft trænger ind gennem revner og utætte samlinger......, fx omkring rør til kloak, vand og varmeforsyning. Koncentrationen af radon i jorden varierer meget fra sted til sted, også lokalt og gennem året. Tidligere undersøgelser har vist, at der kan forekomme høje koncentrationer i Sydgrønland, specielt i området syd for Narsalik ved Paamiut, 61°30’N....

  9. The use of radon as tracer in environmental sciences

    Science.gov (United States)

    Quindos Poncela, Luis; Sainz Fernandez, Carlos; Fuente Merino, Ismael; Gutierrez Villanueva, Jose; Gonzalez Diez, Alberto

    2013-08-01

    Radon can be used as a naturally occurring tracer for environmental processes. By means of grab-sampling or continuous monitoring of radon concentration, it is possible to assess several types of dynamic phenomena in air and water. We present a review of the use of radon and its progeny at the University of Cantabria. Radon can be an atmospheric dynamics indicator related with air mass interchange near land-sea discontinuities as well as for the study of vertical variations of air parameters (average values of different types of stability: 131-580 Bq m-3). Concerning indoor gas, we present some results obtained at Altamira Cave (Spain): from 222 to 6549 Bq m-3 (Hall) and from 999 to 6697 Bq m-3 (Paintings Room). Finally, variations of radon concentration in soil (0.3 to 9.1 kBq m-3) and underground water (values up to 500 Bq l-1) provide relevant information about different geophysical phenomena.

  10. Radon depletion in xenon boil-off gas

    Energy Technology Data Exchange (ETDEWEB)

    Bruenner, S.; Cichon, D.; Lindemann, S.; Undagoitia, T.M.; Simgen, H. [Max-Planck-Institut fuer Kernphysik, Heidelberg (Germany)

    2017-03-15

    An important background in detectors using liquid xenon for rare event searches arises from the decays of radon and its daughters. We report for the first time a reduction of {sup 222}Rn in the gas phase above a liquid xenon reservoir. We show a reduction factor of >or similar 4 for the {sup 222}Rn concentration in boil-off xenon gas compared to the radon enriched liquid phase. A semiconductor-based α-detector and miniaturized proportional counters are used to detect the radon. As the radon depletion in the boil-off gas is understood as a single-stage distillation process, this result establishes the suitability of cryogenic distillation to separate radon from xenon down to the 10{sup -15} mol/mol level. (orig.)

  11. Radon in land use planning; Radon i arealplanlegging

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2012-11-01

    Radon poses a health risk. Therefore, it is important that the municipality takes into account radon, in land use planning. This Radiation Info provides an overview of what makes an additional radon prone area and what tools are available to assess this. The background is the Planning and Building Act provisions on risk analysis (ROS) and zones. (eb)

  12. Geologic influence on indoor radon concentrations and gamma radiation levels in Norwegian dwellings

    Energy Technology Data Exchange (ETDEWEB)

    Sundal, Aud Venche

    2003-09-01

    Indoor radon levels in 1618 Norwegian dwellings located in different geological settings were compared with geological information in order to determine potential correlations between geological factors and indoor radon concentrations in Norway and to establish whether geological information is useful in radon risk analysis. In two geographically limited areas, Kinsarvik and Fen, detailed geological and geochemical investigations were carried out in order to explain their elevated natural radiation environment. Significant correlations between geology and indoor radon concentrations in Norway are found when the properties of both the bedrock and the overburden are taken into account. Areas of high radon risk in Norway include 1) exposed bedrock with elevated levels of radium (mainly alum shale and granites) and b) highly permeable unconsolidated sediments derived from all rock types (mainly glaciofluvial and fluvial deposits) and moderately permeable sediments containing radium rich rock fragments (mainly basal till). More than 20 % of Norwegian dwellings located in the high-risk areas can be expected to contain radon levels exceeding 200 Bq/m3. The elevated radon risk related to penneable building grounds is illustrated in Kinsarvik where the highly permeable sediments and the large vadose zone underlying the Huse residential area enable the transport of radon from large volumes into the dwellings resulting in enhanced indoor radon concentrations. Subterranean air flows caused by temperature/pressure differences between soil air and atmospheric air and elevations differences within the Huse area are shown to strongly affect the annual variations in indoor radon concentrations. The marked contrasts in radon risk potential between different types of building grounds are clearly illustrated in the Fen area where outcrops of the radium rich Fen carbonatites represent areas of high radon risk while only low levels of both indoor radon concentrations and indoor gamma

  13. Low-cost Radon Reduction Pilot Study

    Energy Technology Data Exchange (ETDEWEB)

    Rose, William B. [Univ. of Illinois, Urbana-Champaign, IL (United States); Francisco, Paul W. [Univ. of Illinois, Urbana-Champaign, IL (United States); Merrin, Zachary [Univ. of Illinois, Urbana-Champaign, IL (United States)

    2015-09-01

    The U.S. Department of Energy's Building America research team Partnership for Advanced Residential Retrofits conducted a primary scoping study on the impact of air sealing between the foundation and the living space on radon transport reduction across the foundation and living space floor assembly. Fifteen homes in the Champaign, Illinois, area participated in the study. These homes were instrumented for hourly continuous radon measurements and simultaneous temperature and humidity measurements. Blower door and zone pressure diagnostics were conducted at each house. The treatments consisted of using air-sealing foams at the underside of the floor that separated the living space from the foundation and providing duct sealing on the ductwork that is situated in the foundation area. The hypothesis was that air sealing the floor system that separated the foundation from the living space should better isolate the living space from the foundation; this isolation should lead to less radon entering the living space from the foundation. If the hypothesis had been proven, retrofit energy-efficiency programs may have chosen to adopt these isolation methods for enhanced radon protection to the living space.

  14. Radon: a bibliography

    Energy Technology Data Exchange (ETDEWEB)

    Lepman, S.R.; Boegel, M.L.; Hollowell, C.D.

    1981-01-01

    The Lawrence Berkeley Laboratory, with the support of the Department of Energy, has developed a computerized database to manage research information in the area of building ventilation and indoor air quality. This literature survey contains references pertaining to the physical properties of radon and its daughters, instrumentation for their measurement, health effects, surveys and measurements, and regulatory information. The references in the bibliography are sequenced in alphabetical order and abstracts are included when supplied by the author. The objective of this report is to disseminate the bibliographic references compiled at the laboratory relating to radon research portion of the program. Interested database users are encouraged to contact the laboratory to receive instructions for direct database acess. A flyer describing the database is supplied at the end of the bibliography and a brief overview of the Radon Research porgram is given.

  15. Atmospheric radon: origin and transfer

    Energy Technology Data Exchange (ETDEWEB)

    Segovia, N.; Tamez, E.; Pena, P.; Gaso, I. [Instituto Nacional de Investigaciones Nucleares, Mexico City (Mexico); Mireles, F.; Davila, I.; Quirino, L. [Universidad Autonoma de Zacatecas (Mexico). Centro Regional de Estudios Nucleares

    1994-12-31

    Atmospheric indoor and outdoor radon surveys have been performed in several locations of Mexico. In order to estimate the radon transfer from different origins to the atmosphere, soil and ground water, together with the exhalation rate from bare and coated building materials have also been studied. The radon detection was performed with SSNTD, an automatic silicon-based radon monitor and the liquid scintillation technique. The results from several years of monitoring indicate that the atmospheric radon behaviour is different for the countryside as compared with more complex inhabited regions; transfer from soil being inhibited by the specific structures of the cities. The effect of wall coatings reduced from 50% to 90% the radon exhalation from bare building materials. A low radon content was observed in the ground water samples studied. (Author).

  16. Radon assay for SNO+

    Energy Technology Data Exchange (ETDEWEB)

    Rumleskie, Janet [Laurentian University, Greater Sudbury, Ontario (Canada)

    2015-12-31

    The SNO+ experiment will study neutrinos while located 6,800 feet below the surface of the earth at SNOLAB. Though shielded from surface backgrounds, emanation of radon radioisotopes from the surrounding rock leads to back-grounds. The characteristic decay of radon and its daughters allows for an alpha detection technique to count the amount of Rn-222 atoms collected. Traps can collect Rn-222 from various positions and materials, including an assay skid that will collect Rn-222 from the organic liquid scintillator used to detect interactions within SNO+.

  17. Modeling and experimental examination of water level effects on radon exhalation from fragmented uranium ore.

    Science.gov (United States)

    Ye, Yong-Jun; Dai, Xin-Tao; Ding, De-Xin; Zhao, Ya-Li

    2016-12-01

    In this study, a one-dimensional steady-state mathematical model of radon transport in fragmented uranium ore was established according to Fick's law and radon transfer theory in an air-water interface. The model was utilized to obtain an analytical solution for radon concentration in the air-water, two-phase system under steady state conditions, as well as a corresponding radon exhalation rate calculation formula. We also designed a one-dimensional experimental apparatus for simulating radon diffusion migration in the uranium ore with various water levels to verify the mathematical model. The predicted results were in close agreement with the measured results, suggesting that the proposed model can be readily used to determine radon concentrations and exhalation rates in fragmented uranium ore with varying water levels. Copyright © 2016. Published by Elsevier Ltd.

  18. Description of the behavior of an aquifer by using continuous radon monitoring in a thermal spa

    Energy Technology Data Exchange (ETDEWEB)

    Sainz, Carlos, E-mail: sainzc@unican.es; Rábago, Daniel; Fuente, Ismael; Celaya, Santiago; Quindós, Luis Santiago

    2016-02-01

    Radon ({sup 222}Rn) levels in air and water have been analyzed continuously for almost a year in Las Caldas de Besaya thermal spa, north Spain. Radon is a naturally occurring noble gas from the decay of radium ({sup 226}Ra) both constituents of radioactive uranium 238 series. It has been recognized as a lung carcinogen by the World Health Organization (WHO) and International Agency for Research on Cancer (IARC). Furthermore the Royal Decree R.D 1439/2010 of November, 2010 establishes the obligation to study occupational activities where workers and, where appropriate, members of the public are exposed to inhalation of radon in workplaces such as spas. Together with radon measures several physico-chemical parameters were obtained such as pH, redox potential, electrical conductivity and air and water temperature. The devices used for the study of the temporal evolution of radon concentration have been the RTM 2100, the Radon Scout and gamma spectrometry was complementarily used to determine the transfer factor of the silicone tubes in the experimental device. Radon concentrations obtained in water and air of the spa are high, with an average of 660 Bq/l and 2900 Bq/m{sup 3} respectively, where water is the main source of radon in the air. Radiation dose for workers and public was estimated from these levels of radon. The data showed that the thermal processes can control the behavior of radon which can be also influenced by various physical and chemical parameters such as pH and redox potential. - Highlights: • Radon in water is the major source of indoor air radon concentration in thermal facilities. • Radon in water has been used to characterize the origin of water used for treatments in a spa. • Preliminary dose assessment from radon exposure has been performed.

  19. EVALUATION OF RADON EMANATION FROM SOIL WITH VARYING MOISTURE CONTENT IN A SOIL CHAMBER

    Science.gov (United States)

    The paper describes measurements to quantitatively identify the extent to which moisture affects radon emanation and diffusive transport components of a sandy soil radon concentration gradient obtained in the EPA test chamber. The chamber (2X2X4 m long) was constructed to study t...

  20. Typhoon and elevated radon level in a municipal water supply

    Energy Technology Data Exchange (ETDEWEB)

    Mao, Cheng-Hsin [Nuclear Science and Development Center, National Tsing Hua Univ., Taiwan (China); Weng, Pao-Shan [Radiation Protection Association ROC, Taiwan (China)

    2000-05-01

    The Municipal Water Supply at Hsinchu City is a water treatment plant using poly- aluminum chloride (PAC) for coagulation and then followed by precipitation and filtration. Its capacity is 70,000 m{sup 3}/day. The raw water is drawn from the nearby river. Since the subject of interest is the radon level during typhoon season, the sampling period was from March to December 1999. Commercially available electret was used for water samples taken from the five ponds in the plant. This technique relies on the measurement of radon in air above a water sample enclosed in a sealed vessel. The concentration of airbone radon released from water was determined by means of the electret ion chamber. During the first sampling period there came two typhoons. One is called Magie during June 10-17, and the other called Sam during August 20-26. The first typhoon led to the radon level measured from the water samples as high as 705 Bq/m{sup 3}, while the second caused even higher radon level as high as 772 Bq/m{sup 3}. Similar results were obtained for the second sampling period after August till December 1999. For those measured without typhoon influence, the average radon was lower from the coagulation pond yet without coagulation process during March through August 1999. However, water samples taken from the pond after precipitation did not show similar results in radon level. (author)

  1. Publications about Radon

    Science.gov (United States)

    There is no known safe level of exposure to radon. EPA strongly recommends that you fix your home if your test shows 4 picocuries (pCi/L) or more. These publications and resources will provide you with the information you need to fix your home.

  2. Radon and environmental radioactivity in the Canfranc Underground Laboratory; Radon y radiacion ambiental en el Laboratorio Subterraneo de Canfrac (LSC)

    Energy Technology Data Exchange (ETDEWEB)

    Bandac, I.; Bettini, A.; Borjabad, S.; Nunez-Lagos, R.; Perez, C.; Rodriguez, S.; Sanchez, P.; Villar, J. A.

    2014-02-01

    The results of more than one year of measurements of Radon and environmental radioactivity in the Canfranc Underground Laboratory (LSC) are presented. Radon and atmospheric parameters have registered by an Alpha guard P30 equipment and the environmental radioactivity has been measured by means of UD-802A Panasonic thermoluminescent dosimeters (TLD) processed by an UD716 Panasonic unit. Series of results along with their possible correlations are presented. Both the Radon level and the ambient dose equivalent H (10) are much lower than the allowed ones so no radiological risk exists to persons working in the LSC. Also its excellent environmental radiological quality has been confirmed. (Author)

  3. Radon Resources for Home Buyers and Sellers

    Science.gov (United States)

    ... a Home Radon-Resistant New Construction Radon and Real Estate Resources Home Buyer's/Seller's Guide to Radon Consumer's ... Water A-Z Index Laws & Regulations By Business Sector By Topic Compliance Enforcement Laws and Executive Orders ...

  4. Transport Processes in High Temperature QCD Plasmas

    Science.gov (United States)

    Hong, Juhee

    The transport properties of high temperature QCD plasmas can be described by kinetic theory based on the Boltzmann equation. At a leading-log approximation, the Boltzmann equation is reformulated as a Fokker-Planck equation. First, we compute the spectral densities of Tµν and Jµ by perturbing the system with weak gravitational and electromagnetic fields. The spectral densities exhibit a smooth transition from free-streaming quasi-particles to hydrodynamics. This transition is analyzed with hydrodynamics and diffusion equation up to second order. We determine all of the first and second order transport coefficients which characterize the linear response in the hydrodynamic regime. Second, we simulate the wake of a heavy quark moving through the plasmas. At long distances, the energy density and flux distributions show sound waves and a diffusion wake. The kinetic theory calculations based on the Boltzmann equation at weak coupling are compared to the strong coupling results given by the AdS/CFT correspondence. By using the hard-thermal-loop effective theory, we determine the photon emission rate at next-to-leading order (NLO), i.e., at order g2mD /T. There are three mechanisms which contribute to the leading-order photon emission: (2 ↔ 2) elastic scatterings, (1 ↔ 2) collinear bremsstrahlung, and (1 ↔ 1) quark-photon conversion due to soft fermion exchange. At NLO, these three mechanisms are not completely independent. When the transverse momentum between quark and photon becomes soft, the Compton scattering with a soft gluon reduces to wide-angle bremsstrahlung. Similarly, bremsstrahlung reduces to the quark-photon conversion process when the photon carries most of the incoming momentum. Therefore, the rates should be matched to determine the wide-angle NLO correction. Collinear bremsstrahlung can be accounted for by solving an integral equation which corresponds to summing ladder diagrams. With O(g) corrections in the collision kernel and the asymptotic

  5. The NIST Primary Radon-222 Measurement System

    OpenAIRE

    Coll, R.; Hutchinson, J. M. R.; Unterweger, M. P.

    1990-01-01

    Within the United States, the national standard for radon measurements is embodied in a primary radon measurement system that has been maintained for over 50 years to accurately measure radon (222Rn) against international and national radium (226Ra) standards. In turn, all of the radon measurements made at the National Institute of Standards and Technology (NIST) and the radon transfer calibration standards and calibration services provided by NIST are directly related to this national radon ...

  6. Role of astrocytic transport processes in glutamatergic and GABAergic neurotransmission

    DEFF Research Database (Denmark)

    Schousboe, A; Sarup, A; Bak, L K

    2004-01-01

    The fine tuning of both glutamatergic and GABAergic neurotransmission is to a large extent dependent upon optimal function of astrocytic transport processes. Thus, glutamate transport in astrocytes is mandatory to maintain extrasynaptic glutamate levels sufficiently low to prevent excitotoxic...

  7. Analysis of clusterization and networking processes in developing intermodal transportation

    Directory of Open Access Journals (Sweden)

    Sinkevičius Gintaras

    2016-06-01

    Full Text Available Analysis of the processes of clusterization and networking draws attention to the necessity of integration of railway transport into the intermodal or multimodal transport chain. One of the most widespread methods of combined transport is interoperability of railway and road transport. The objective is to create an uninterrupted transport chain in combining several modes of transport. The aim of this is to save energy resources, to form an effective, competitive, attractive to the client and safe and environmentally friendly transport system.

  8. Legal issues in radon affairs

    Energy Technology Data Exchange (ETDEWEB)

    Massuelle, M.H. [Inst. de Protection et de Surete Nucleaire, Fontenay aux Roses (France)

    1999-12-01

    In France, it was only recently that cases related to high radon concentrations in dwellings received substantial publicity. This irruption of radon as a public health issue came with the general progress of scientific knowledge and the availability of a research capacity in France able to develop expertise. We are interested here in the legal implications of issues that arise from the lag between the activity of expertsand the regulatory activity in the domain of radon. We use the term expertise very broadly, to cover the practical application of research findings, the relation of the researchers with the community, and finally the acts by which experts provide their knowledge to the community. We first examine the course by which science developed the radon issue and the way they organized to move from research to expertise; here we try to characterize the various needs for radon expertise. We then discuss the legal difficulties associated with radon expertise.

  9. Impact of radon and combinatory radon/carbon dioxide spa on pain and hypertension: Results from the explorative RAD-ON01 study.

    Science.gov (United States)

    Rühle, Paul F; Klein, Gerhart; Rung, Tatjana; Tiep Phan, Hong; Fournier, Claudia; Fietkau, Rainer; Gaipl, Udo S; Frey, Benjamin

    2018-02-16

    Therapies with low doses of radon have beneficial effects on patients suffering from chronic painful degenerative and inflammatory diseases. We already showed that this is accompanied by systemic immune modulations. We here focus on pain reducing effects of very low doses of radon by adding carbon dioxide water and its impact on heart rate variability (HRV), blood pressure and free radicals. 100 patients receiving radon spa (1.200 Bq/l at 34°C or 600 Bq/l, 1 g/l CO 2 at 34°C) were monitored before and at three different time points after therapy. Individual pain perception was analyzed and the capability to process radicals. At each time point the hypertensive patients (n = 46) were examined over 24h for blood pressure and HRV. Long term pain reduction was observed in the majority of patients. A modulation of superoxide dismutase was identified, presumably representing a priming effect for lowering radiation stress. Further, lowering of blood pressure, especially in those patients who additionally received carbon dioxide, was seen. Radon did in particular impact on HRV implying lasting relaxation effects. Radon/carbon dioxide spa efficiently reduces pain. In particular, patients simultaneously suffering from painful and cardiovascular diseases should be treated by combination of radon and CO 2 .

  10. Soil gas and radon entry into a simple test structure: Comparison of experimental and modelling results

    DEFF Research Database (Denmark)

    Andersen, C.E.; Søgaard-Hansen, J.; Majborn, B.

    1994-01-01

    A radon test structure has been established at a field site at Riso National Laboratory. Measurements have been made of soil gas entry rates, pressure couplings and radon depletion. The experimental results have been compared with results obtained from measured soil parameters and a two......-dimensional steady-state numerical model of Darcy flow and combined diffusive and advective transport of radon. For most probe locations, the calculated values of the pressure couplings and the radon depletion agree well with the measured values, thus verifying important elements of the Darcy flow approximation......, and the ability of the model to treat combined diffusive and advective transport of radon. However, the model gives an underestimation of the soil gas entry rate. Even if it is assumed that the soil has a permeability equal to the highest of the measured values, the model underestimates the soil gas entry rate...

  11. Charge Transport Processes in Molecular Junctions

    Science.gov (United States)

    Smith, Christopher Eugene

    Molecular electronics (ME) has evolved into a rich area of exploration that combines the fields of chemistry, materials, electronic engineering and computational modeling to explore the physics behind electronic conduction at the molecular level. Through studying charge transport properties of single molecules and nanoscale molecular materials the field has gained the potential to bring about new avenues for the miniaturization of electrical components where quantum phenomena are utilized to achieve solid state molecular device functionality. Molecular junctions are platforms that enable these studies and consist of a single molecule or a small group of molecules directly connected to electrodes. The work presented in this thesis has built upon the current understanding of the mechanisms of charge transport in ordered junctions using self-assembled monolayer (SAM) molecular thin films. Donor and acceptor compounds were synthesized and incorporated into SAMs grown on metal substrates then the transport properties were measured with conducting probe atomic force microscopy (CP-AFM). In addition to experimentally measured current-voltage (I-V) curves, the transport properties were addressed computationally and modeled theoretically. The key objectives of this project were to 1) investigate the impact of molecular structure on hole and electron charge transport, 2) understand the nature of the charge carriers and their structure-transport properties through long (electronic coupling from experimental I-V curves. Here, we lay ground work for creating a more complete picture of charge transport in macroscopically ordered molecular junctions of controlled architecture, length and charge carrier. The polaronic nature of hopping transport has been predicted in long, conjugated molecular wires. Using quantum-based calculations, we modeled 'p-type' polaron transport through oligophenylenethiophene (OPTI) wires and assigned transport activation energies to specific modes of

  12. Evaluation of the open vial method in the radon measurement; Evaluacion del metodo del vial abierto en la medicion de radon

    Energy Technology Data Exchange (ETDEWEB)

    Lopez del Rio, H.; Davila R, J. I.; Mireles G, F., E-mail: hlopezdelrio@hotmail.com [Universidad Autonoma de Zacatecas, Unidad Academica de Estudios Nucleares, Cipres No. 10, Fracc. La Penuela, 98068 Zacatecas (Mexico)

    2014-10-15

    The open vial method is a simple technique, under-utilized but that take advantage of the great radon solubility in organic solvents, therefore applies in the measurement of the radon concentration exhaled in soil. The method consists on the exposition to the gas radon of an open vial with scintillating solution. An integral mathematical model for indoors that describes the emanation processes and gas radon exhalation was developed, as well as the radon dissolution in the scintillation liquid, besides obtaining the characteristic parameters of the experimental system proposed for the radon concentration calculation exhaled by soils. Two experimental arrangements were designed with exposition cameras of 12 and 6 L and quantity of different soil. The open vial was prepared with a mixture of 8 ml of deionized water and 12 ml of scintillation liquid OptiPhase Hi Safe 3 in polyethylene vials; the measurements of the dissolved radon were carried out in scintillation liquid equipment. As a result, on average 2.0% of the exhaled radon is dissolved in the open vial and the dissolved fraction is independent of the experimental arrangement. Also was observed that the exposition time does not affect the radon dissolution significantly, in correspondence with the reported in the literature. (Author)

  13. Radon intercomparison measurements 2004 at PSI; Die Vergleichsmessung 2004 fuer Radongasmessgeraete am PSI

    Energy Technology Data Exchange (ETDEWEB)

    Butterweck, G.; Schuler, C

    2004-08-01

    Twelve radon measurement services participated in the 2004 Radon Intercomparison Exercise performed at the Reference Laboratory for Radon Gas Activity Concentration Measurements at Paul Scherrer Institut (PSI) during March 5{sub th} to 16{sub th}, 2004. Ten of these laboratories were approved by the Swiss Federal Office of Public Health and their participation in the intercomparison exercise was a requirement to warrant quality of measurement. Radon gas detectors (etched-track and electret ionisation chambers) and instruments (ionisation chambers and electrostatic precipitation) were exposed in the PSI Radon Chamber in a reference atmosphere with an average radon gas concentration of 5516 Bqm{sup -3} leading to a radon gas exposure of 1458 kBqhm{sup -3}. This exposure was above the measuring range of participating LST electret ionisation chambers. Thus, these detector were exposed for a shorter period leading to a radon gas exposure of 401 kBqhm{sup -3} at an average radon gas concentration of 5538 Bqm{sup -3}. Additional five etched-track detectors of an approved measuring service were purchased by the Swiss Federal Office of Public Health for a spot check. Two of these were exposed over the complete exposure interval, two were removed from the exposure chamber together with the LST electret ionisation chambers and another was used as transport detector. The results of these detectors showed an even larger difference to the target value and a larger standard deviation than the detectors submitted for the intercomparison exercise by the measuring service. (author)

  14. Radon intercomparison measurements 2005 at PSI; Die Vergleichsmessung 2005 fuer Radongasmessgeraete am PSI

    Energy Technology Data Exchange (ETDEWEB)

    Butterweck, G.; Schuler, C

    2005-06-01

    Thirteen radon measurement services participated in the 2005 Radon Intercomparison Exercise performed at the Reference Laboratory for Radon Gas Activity Concentration Measurements at Paul Scherrer Institut (PSI) during March 4{sub th} to 15{sub th}, 2004. Ten of these laboratories were approved by the Swiss Federal Office of Public Health and their participation in the intercomparison exercise was a requirement to warrant quality of measurement. Radon gas detectors (etched-track and electret ionisation chambers) and instruments (ionisation chambers and electrostatic precipitation) were exposed in the PSI Radon Chamber in a reference atmosphere with an average radon gas concentration of 3467 Bqm{sup -3} leading to a radon gas exposure of 914 kBqhm{sup -3}. This exposure was above the measuring range of participating LST electret ionisation chambers. Thus, these detector were exposed for a shorter period leading to a radon gas exposure of 416 kBqhm{sup -3} at an average radon gas concentration of 3472 Bqm{sup -3}. Additional six electret ionisation chamber detectors of an approved measuring service were purchased by the Swiss Federal Office of Public Health for a spot check. Two of these were exposed over the complete exposure interval, two were removed from the exposure chamber together with the LST electret ionisation chambers and another was used as transport detector. The results of these detectors showed an even larger difference to the target value and a larger standard deviation than the detectors submitted for the intercomparison exercise by the measuring service. (author)

  15. Radon Gas Measurement Intercomparison 2002 at PSI; Die Vergleichsmessung 2002 fuer Radongasmessgeraete am PSI

    Energy Technology Data Exchange (ETDEWEB)

    Butterweck, G.; Schuler, C

    2002-07-01

    Fifteen radon measurement services participated in the 2002 Radon Intercomparison Exercise performed at the Reference Laboratory for Radon Gas Activity Concentration Measurements at Paul Scherrer Institut (PSI) during March 7th to 18th, 2002. Eleven of these laboratories were approved by the Swiss Federal Office of Public Health and their participation in the intercomparison exercise was a requirement to warrant traceability to national or international standards. Radon gas detectors (etched-track and electret ionisation chambers) and instruments (ionisation chambers, scintillation cells and electrostatic precipitation) were exposed in the PSI Radon Chamber in a reference atmosphere with an average radon gas concentration of 2700 Bqm{sup -3} leading to a radon gas exposure of 700 kBqhm{sup -3}. Additional five detectors of an approved measuring service were purchased by the Swiss Federal Office of Public Health for a spot check. Two of these were exposed as described above, two had an exposure of 380 kBqhm{sup -3} at an identical average radon concentration and another was used as transport detector. The results of these detectors showed a larger difference to the target value and a larger standard deviation than the detectors submitted for the intercomparison exercise by the measuring service. Similar to the intercomparison exercises of 1998, 1999 and 2000 aerosol particles were generated continuously during the intercomparison with a burning candle to increase the equilibrium factor F between radon progeny and radon gas to values observed under living conditions. Nevertheless, open etched-track detectors showed a significant deviation to the target value. The relative air humidity in the radon chamber during the intercomparison was 70% due to water vapour production by the burning candles. As was observed in the past, one electret detector showed a result much higher than the target radon concentration. The cause may be a discharge across the surface of the

  16. Indoor radon distribution in Switzerland: lognormality and Extreme Value Theory

    Energy Technology Data Exchange (ETDEWEB)

    Tuia, Devis [Institute of Geomatics and Analysis of Risk (IGAR), University of Lausanne, CH-1015 Lausanne (Switzerland)], E-mail: devis.tuia@unil.ch; Kanevski, Mikhail [Institute of Geomatics and Analysis of Risk (IGAR), University of Lausanne, CH-1015 Lausanne (Switzerland)

    2008-04-15

    Analysis and modeling of statistical distributions of indoor radon concentration from data valorization to mapping and simulations are critical issues for real decision-making processes. The usual way to model indoor radon concentrations is to assume lognormal distributions of concentrations on a given territory. While these distributions usually model correctly the main body of the data density, they cannot model the extreme values, which are more important for risk assessment. In this paper, global and local indoor radon distributions are modeled using Extreme Value Theory (EVT). Emphasis is put on the tails of the distributions and their deviations from lognormality. The best fits of distributions to real data set density have been computed and goodness of fit with Root Mean Squared Error (RMSE) is evaluated. The results show that EVT performs better than lognormal pdf for real data sets characterized by high indoor radon concentrations.

  17. Infinite measure~preserving~transformations with Radon MSJ

    OpenAIRE

    Danilenko, Alexandre I.

    2015-01-01

    We introduce concepts of Radon MSJ and Radon disjointness for infinite Radon measure preserving homeomorphisms of the locally compact Cantor space. We construct an uncountable family of pairwise Radon disjoint infinite Chacon like transformations. Every such transformation is Radon strictly ergodic, totally ergodic, asymmetric (not isomorphic to its inverse), has Radon MSJ and possesses Radon joinings whose ergodic components are not joinings.

  18. Financially Constrained Transportation Planning and Programming Process

    Science.gov (United States)

    1997-03-01

    This case study report is intended to provide metropolitan planning organizations (MPOs), state departments of transportation and transit agencies with a greater understanding of the important role that financial information plays in the planning and...

  19. Environmental radon with RAD7 detector; Radon ambiental con detector RAD7

    Energy Technology Data Exchange (ETDEWEB)

    Lopez M, A.; Balcazar, M. [ININ, Carretera Mexico-Toluca s/n, 52750 Ocoyoacac, Estado de Mexico (Mexico); Fernandez G, I. M.; Capote F, E., E-mail: arturo.lopez@inin.gob.mx [Centro de Proteccion e Higiene de las Radiaciones, Carretera La Victoria II Km 2.5 e/ Monumental y Final, Guanabacoa, La Habana (Cuba)

    2016-09-15

    Experimental results of the radon detection with the equipment RAD7 are presented. The use of a solid state detector placed in a semi-spherical chamber with an electric field allows a high sensitivity of 0.4 cpm/P Ci/l. Radon detection is achieved by the spectroscopy of its decay products. In accordance with a table of errors for various ranges of counts and radon concentrations, reported by the manufacturer, an equation was obtained that allows establishing operation criteria of the equipment. For radon detection at ambient concentrations as low as 30 Bq m{sup -3}, is shown that short counts of 10 minutes are good enough to make decisions on radiation protection matter. In places where concentrations are close to 200 Bq m{sup -3}, counting intervals of the order of 0.5 hours will have an acceptable counting error of the order of 20%. The determination of radon in soil was, according to the expected, on the order of 10 kBq m{sup -3}, and was found that even with the recommended counting times of 5 minutes, there is a risk of increased humidity inside the detector above 20% Rh, with associated reduction of detection efficiency, if the desiccant is not used properly. The equipment was subjected to a radon exposure in air of 13, 373 Bq m{sup -3} ± 3.7%, contained within a controlled chamber, with a variation in temperature of (19-21) degrees Celsius and in the relative humidity of (5-7) %, the good stability of the chamber allows to propose calibration processes of these equipment s by assessing the concentration by means of a Ge (Hp) detector. (Author)

  20. Mapping geogenic radon potential by regression kriging

    Energy Technology Data Exchange (ETDEWEB)

    Pásztor, László [Institute for Soil Sciences and Agricultural Chemistry, Centre for Agricultural Research, Hungarian Academy of Sciences, Department of Environmental Informatics, Herman Ottó út 15, 1022 Budapest (Hungary); Szabó, Katalin Zsuzsanna, E-mail: sz_k_zs@yahoo.de [Department of Chemistry, Institute of Environmental Science, Szent István University, Páter Károly u. 1, Gödöllő 2100 (Hungary); Szatmári, Gábor; Laborczi, Annamária [Institute for Soil Sciences and Agricultural Chemistry, Centre for Agricultural Research, Hungarian Academy of Sciences, Department of Environmental Informatics, Herman Ottó út 15, 1022 Budapest (Hungary); Horváth, Ákos [Department of Atomic Physics, Eötvös University, Pázmány Péter sétány 1/A, 1117 Budapest (Hungary)

    2016-02-15

    Radon ({sup 222}Rn) gas is produced in the radioactive decay chain of uranium ({sup 238}U) which is an element that is naturally present in soils. Radon is transported mainly by diffusion and convection mechanisms through the soil depending mainly on the physical and meteorological parameters of the soil and can enter and accumulate in buildings. Health risks originating from indoor radon concentration can be attributed to natural factors and is characterized by geogenic radon potential (GRP). Identification of areas with high health risks require spatial modeling, that is, mapping of radon risk. In addition to geology and meteorology, physical soil properties play a significant role in the determination of GRP. In order to compile a reliable GRP map for a model area in Central-Hungary, spatial auxiliary information representing GRP forming environmental factors were taken into account to support the spatial inference of the locally measured GRP values. Since the number of measured sites was limited, efficient spatial prediction methodologies were searched for to construct a reliable map for a larger area. Regression kriging (RK) was applied for the interpolation using spatially exhaustive auxiliary data on soil, geology, topography, land use and climate. RK divides the spatial inference into two parts. Firstly, the deterministic component of the target variable is determined by a regression model. The residuals of the multiple linear regression analysis represent the spatially varying but dependent stochastic component, which are interpolated by kriging. The final map is the sum of the two component predictions. Overall accuracy of the map was tested by Leave-One-Out Cross-Validation. Furthermore the spatial reliability of the resultant map is also estimated by the calculation of the 90% prediction interval of the local prediction values. The applicability of the applied method as well as that of the map is discussed briefly. - Highlights: • A new method

  1. Intercomparison 2003 for Radon measurement services at PSI; Die Vergleichsmessung 2003 fuer Radongasmessgeraete am PSI

    Energy Technology Data Exchange (ETDEWEB)

    Butterweck, G.; Schuler, C

    2003-09-01

    Twelve radon measurement services participated in the 2003 Radon Intercomparison Exercise performed at the Reference Laboratory for Radon Gas Activity Concentration Measurements at Paul Scherrer Institut (PSI) during March 13th to 24th, 2003. Ten of these laboratories were approved by the Swiss Federal Office of Public Health and their participation in the intercomparison exercise was a requirement to warrant quality of measurement. Radon gas detectors (etched-track and electret ionisation chambers) and instruments (ionisation chambers and electrostatic precipitation) were exposed in the PSI Radon Chamber in a reference atmosphere with an average radon gas concentration of 1950 Bqm{sup -3} leading to a radon gas exposure of 517 kBqhm{sup -3}. Additional five electret-detectors of an approved measuring service were purchased by the Swiss Federal Office of Public Health for a spot check. Two of these were exposed as described above, two had an exposure of 247 kBqhm{sup -3} at an average radon concentration of 1960 Bqm{sup -3} and another was used as transport detector. The results of these detectors showed a larger difference to the target value and a larger standard deviation than the detectors submitted for the intercomparison exercise by the measuring service. The unexposed transport detector showed a notedly too high signal. For the first time in this series of intercomparisons, no open etched-track detectors participated. Thus, the generation of aerosol particles with burning candles was not necessary. (author)

  2. MODEL FOR UNSTEADY OF DIFFUSION –ADVECTION OF RADON IN SOIL – ATMOSPHERE

    Directory of Open Access Journals (Sweden)

    Parovik R.I.

    2010-04-01

    Full Text Available We consider a mathematical model for unsteady transport of radon from the constant coefficients in the soil – atmosphere. An explicit analytical solution for this model and built at different times of his profiles.

  3. Radon Infiltration in Rented Accommodation

    DEFF Research Database (Denmark)

    Rasmussen, Torben Valdbjørn

    2017-01-01

    Indoor radon levels were measured in 221 homes located in 53 buildings, including 28 multi-occupant houses and 25 single-family terraced houses. The homes consisted of rented accommodation located in buildings recorded as being constructed before 2010 and after the year 1850. The radon level...

  4. Radon - The management of the risk related to radon; Le radon la gestion du risque lie au radon

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2010-07-01

    This leaflet briefly explains what radon is, where it comes from, and what it becomes. It indicates and briefly comments its concentrations in French departments, describes how radon can affect our health (lung cancer), describes how the risk can be reduced in buildings, and indicates the existing regulatory provisions

  5. The dynamics of local processes towards environmentally sustainable transport

    DEFF Research Database (Denmark)

    Hansen, Carsten Jahn

    1999-01-01

    The paper explores and discusses the dynamics of local leading towards the creation of an environmentally sustainable transport system. processes......The paper explores and discusses the dynamics of local leading towards the creation of an environmentally sustainable transport system. processes...

  6. The NIST Primary Radon-222 Measurement System.

    Science.gov (United States)

    Collé, R; Hutchinson, J M R; Unterweger, M P

    1990-01-01

    Within the United States, the national standard for radon measurements is embodied in a primary radon measurement system that has been maintained for over 50 years to accurately measure radon ((222)Rn) against international and national radium ((226)Ra) standards. In turn, all of the radon measurements made at the National Institute of Standards and Technology (NIST) and the radon transfer calibration standards and calibration services provided by NIST are directly related to this national radon standard. This primary radon measurement system consists of pulse ionization chambers and ancillary gas handling and gas purification equipment. The system is currently undergoing a significant upgrading and expansion which will replace the extant outdated system.

  7. Simulation Models in Testing Reliability of Transport Process

    Directory of Open Access Journals (Sweden)

    Jacyna Marianna

    2016-07-01

    Full Text Available The paper touches the problem of applying simulation models to assess the reliability of services in transport networks. Investigation of the transport processes in terms of their reliability is a complex decision-making task. The paper describes a method for assessing the reliability of transport process on the base of the criterion of minimizing the normalized lost time of vehicles. The time is wasted in a result of conflict situations occurring in the transport network during the transport process. The study includes stochastic distributions of system input. It enables studying the quality parameters of the transport network equipment, including service providers working under different workload and all kinds of disturbances. The method uses simulation models. Simulation studies were performed with Java Modelling Tools.

  8. Development of Radon-222 as Natural Tracer for Monitoring the Remediation of NAPL in the Subsurface

    Energy Technology Data Exchange (ETDEWEB)

    Brian M. Davis; Lewis Semprini; Jonathan Istok

    2003-02-27

    Naturally occurring 222-radon in ground water can potentially be used as an in situ partitioning tracer to characterize dense nonaqueous phase liquid (DNAPL) saturations. The static method involves comparing radon concentrations in water samples from DNAPL-contaminated and non-contaminated portions of an aquifer. During a push-pull test, a known volume of test solution (radon-free water containing a conservation tracer) is first injected (''pushed'') into a well; flow is then reversed and the test solution/groundwater mixture is extracted (''pulled'') from the same well. In the presence of NAPL radon transport is retarded relative to the conservative tracer. Assuming linear equilibrium partitioning, retardation factors for radon can be used to estimate NAPL saturations.The utility of this methodology was evaluated in laboratory and field settings.

  9. Soil radon survey to assess NAPL contamination from an ancient spill. Do kerosene vapors affect radon partition ?

    Science.gov (United States)

    De Simone, Gabriele; Lucchetti, Carlo; Pompilj, Francesca; Galli, Gianfranco; Tuccimei, Paola; Curatolo, Pierpaolo; Giorgi, Riccardo

    2017-05-01

    A soil radon-deficit survey was carried out in a site polluted with kerosene (Rome, Italy) in winter 2016 to assess the contamination due to the NAPL residual component in the vadose zone and to investigate the role of the vapor plume. Radon is indeed more soluble in the residual NAPL than in air or water, but laboratory experiments demonstrated that it is also preferentially partitioned in the NAPL vapors that transport it and may influence soil radon distribution patterns. Specific experimental configurations were designed and applied to a 31-station grid to test this hypothesis; two RAD7 radon monitors were placed in-series and connected to the top of a hollow probe driven up to 80-cm depth; the first instrument was directly attached to the probe and received humid soil gas, which was counted and then conveyed to the second monitor through a desiccant (drierite) cylinder capturing moisture and eventually the NAPL volatile component plus the radon dissolved in vapors. The values from the two instruments were cross-calibrated through specifically designed laboratory experiments and compared. The results are in agreement within the error range, so the presence of significant NAPL vapors, eventually absorbed by drierite, was ruled out. This is in agreement with low concentrations of soil VOCs. Accordingly, the radon-deficit is ascribed to the residual NAPL in the soil pores, as shown very well also by the obtained maps. Preferential areas of radon-deficit were recognised, as in previous surveys. An average estimate of 21 L (17 Kg) of residual NAPL per cubic meter of terrain is provided on the basis of original calculations, developed from published equations. A comparison with direct determination of total hydrocarbon concentration (23 kg per cubic meter of terrain) is provided. Copyright © 2017 Elsevier Ltd. All rights reserved.

  10. Radon in Saudi houses

    Energy Technology Data Exchange (ETDEWEB)

    Abu-Jarad, F.; Al-Jarallah, M.I.

    1986-01-01

    A total of 637 passive radon dosemeters (CR-39 nuclear track detectors in a closed chamber) were used in a survey in 400 houses in Saudi Arabia. The radon concentration was found to vary from 5 to 36 Bq.m/sup -3/ (0.13 to 0.98 pCi.l/sup -1/) with a mean of 16 Bq.m/sup -3/ (0.43 pCi.l/sup -1/). The unoccupied houses showed a concentration of 29+-7 Bq.m/sup -3/ (0.78+-0.19 pCi.l/sup -1/) double that of the occupied houses, 14+-1 Bq.m/sup -3/ (0.39+-0.02 pCi.l/sup -1/), in the same area. The radon daughter concentration measured with a Working Level monitor in 17 unoccupied houses was found to vary from 1.35x10/sup -3/ to 24x10/sup -3/ WL with an average of 6.9+-1.4x10/sup -3/ WL. The average exhalation rate measured in 37 houses by 95 passive detectors in cans sealed to the walls ranged from 0.013 to 0.044 Bq.m/sup -2/.h/sup -1/(0.35 to 1.2 pCi.m/sup -2/.h/sup -1/) with an average of 0.021+-0.003 Bq.m/sup -2/.h/sup -1/(0.56+-0.09 pCi.m/sup -2/.h/sup -1/). This survey is the first in Saudi Arabia (a hot climate) and can usefully be compared with similar surveys in countries with cold climates.

  11. ANALYSIS OF A TRANSPORT PROCESS USING HYBRID PETRI NETS

    Directory of Open Access Journals (Sweden)

    Elisabeta Mihaela CIORTEA

    2013-05-01

    Full Text Available Purpose of the paper is to analyze the Petri net model, to describe the transport process, part of amanufacturing system and its dynamics.A hibrid Petri net model is built to describe the dinamics of the transport process manufacturingsystem. Mathematical formulation of the dinamycs processes a detailed description. Based on this model, theanalysis of the transport process is designed to be able to execute a production plan and resolve any conflictsthat may arise in the system.In the analysis dinamics known two stages: in the continuous variables are discrete hybrid system in thehibrid discrete variables are used as safety control with very well defined responsibilities.In terms of the chosen model, analyze transport process is designed to help execute a production planand resolve conflicts that may arise in the process, and then the ones in the system

  12. Quaternary deposits and weathered bedrock material as a source of dangerous radon emissions in Estonia

    Directory of Open Access Journals (Sweden)

    Petersell Valter

    2015-06-01

    Full Text Available The risk of dangerous radon emissions in Estonia is high, being among the highest in Europe. In almost 33 per cent of Estonian land area, the content of radon in soil-contained air exceeds the safe limit for unrestricted construction (50 kBq/m3. In such high radon-risk areas the concentration of radon in soil-contained air ranges from 50 to 400 kBq/m3, in a few cases reaching up to 2,100 kBq/m3 exceeding the permitted level for residential areas. The situation is particularly serious in the northernmost part of the country, where uranium-rich graptolite argillite (Dictyonema shale and the Obolus phosphorite are close to ground surface and their particles are constituent parts of Quaternary deposits. Radon emissions from bedrock have been investigated in detail, but to date Quaternary strata as a source of radon emissions are poorly studied. According to our measurements the highest concentrations of radon are related to tills containing clasts and fines of graptolite argillite and phosphorite. Glacial deposits include also granitoidal material, containing U, Th and K, which have been transported by glaciers from the outcrop areas of crystalline basement rocks in Finland and the Gulf of Finland. Due to weathering, outwash and repeated redeposition other genetic types are poorer in radioactive elements and they are weaker sources of radon.

  13. Soil radon measurements as a potential tracer of tectonic and volcanic activity.

    Science.gov (United States)

    Neri, Marco; Ferrera, Elisabetta; Giammanco, Salvatore; Currenti, Gilda; Cirrincione, Rosolino; Patanè, Giuseppe; Zanon, Vittorio

    2016-04-15

    In Earth Sciences there is a growing interest in studies concerning soil-radon activity, due to its potential as a tracer of numerous natural phenomena. Our work marks an advance in the comprehension of the interplay between tectonic activity, volcanic eruptions and gas release through faults. Soil-radon measurements, acquired on Mt. Etna volcano in 2009-2011, were analyzed. Our radon probe is sensitive to changes in both volcanic and seismic activity. Radon data were reviewed in light of the meteorological parameters. Soil samples were analyzed to characterize their uranium content. All data have been summarized in a physical model which identifies the radon sources, highlights the mechanism of radon transport and envisages how such a mechanism may change as a consequence of seismicity and volcanic events. In the NE of Etna, radon is released mainly from a depth of 50 m/day. Three periods of anomalous gas release were found (February 2010, January and February 2011). The trigger of the first anomaly was tectonic, while the second and third had a volcanic origin. These results mark a significant step towards a better understanding of the endogenous mechanisms that cause changes in soil-radon emission at active volcanoes.

  14. Numerical modelling of multiphase flow and transport processes in landfills.

    Science.gov (United States)

    Kindlein, Jonatham; Dinkler, Dieter; Ahrens, Hermann

    2006-08-01

    Waste material in municipal landfills can be described as heterogeneous porous media, where flow and transport processes of gases and liquids are combined with local material degradation. This paper deals with the basic formulation of a multiphase flow and transport model applicable to the numerical analysis of coupled transport and reaction processes inside landfills. The transport model treats landfills within the framework of continuum mechanics, where flow and transport processes are described on a macroscopic level. The composition of organic and inorganic matter in the solid phase and its degradation are modelled on a microscopic scale. The degradation model captures the different reaction schemes of various microbial activities. Subsequently, transport and reaction processes have to be coupled, since emissions at the surface and from the drainage layer depend on the flow of leachate and gas, the transport of various substances and heat, and the biodegradation of organic matter. The theoretical considerations presented here are fundamental to the development of numerical models for the simulation of multiphase flow and transport processes inside landfills coupled with biochemical reactions and heat generation. The implicit modelling of leachate and gas flows including growth and decay of micro-organisms are innovative contributions to landfill modelling

  15. Ionic transport processes in electrochemistry and membrane science

    CERN Document Server

    Kontturi, Kyösti; Manzanares, José A

    2008-01-01

    Modelling of heterogeneous processes, such as electrochemical reactions, extraction or ion-exchange, usually requires solving the transport problem associated to the process. Since the processes at the phase boundary are described by scalar quantities and transport quantities are vectors or tensors, coupling of them can take place only via conservation of mass, charge or momentum. In this book, transport of ionic species is addressed in a versatile manner, emphasizing the mutualcoupling of fluxes in particular. Treatment is based on the formalism of irreversible thermodynamics, i.e. on linear

  16. Radiological assessment of water treatment processes in a water treatment plant in Saudi Arabia: Water and sludge radium content, radon air concentrations and dose rates

    Energy Technology Data Exchange (ETDEWEB)

    Al-Jaseem, Q.Kh., E-mail: qjassem@kacst.edu.sa [Nuclear Science Research Institute (NSRI), King Abdulaziz City for Science and Technology (KACST), P.O. Box 6086, Riyadh 11442 (Saudi Arabia); Almasoud, Fahad I. [Nuclear Science Research Institute (NSRI), King Abdulaziz City for Science and Technology (KACST), P.O. Box 6086, Riyadh 11442 (Saudi Arabia); Ababneh, Anas M. [Physics Dept., Faculty of Science, Islamic University in Madinah, Al-Madinah, P.O. Box 170 (Saudi Arabia); Al-Hobaib, A.S. [Nuclear Science Research Institute (NSRI), King Abdulaziz City for Science and Technology (KACST), P.O. Box 6086, Riyadh 11442 (Saudi Arabia)

    2016-09-01

    There is an increase demand for clean water sources in Saudi Arabia and, yet, renewable water resources are very limited. This has forced the authorities to explore deep groundwater which is known to contain large concentrations of radionuclides, mainly radium isotopes. Lately, there has been an increase in the number of water treatment plants (WTPs) around the country. In this study, a radiological assessment of a WTP in Saudi Arabia was performed. Raw water was found to have total radium activity of 0.23 Bq/L, which exceeds the international limit of 0.185 Bq/L (5 pCi/L). The WTP investigated uses three stages of treatment: flocculation/sedimentation, sand filtration and reverse osmosis. The radium removal efficiency was evaluated for each stage and the respective values were 33%, 22% and 98%. Moreover, the activity of radium in the solid waste generated from the WTP in the sedimentation and sand filtrations stages were measured and found to be 4490 and 6750 Bq/kg, respectively, which exceed the national limit of 1000 Bq/kg for radioactive waste. A radiological assessment of the air inside the WTP was also performed by measuring the radon concentrations and dose rates and were found in the ranges of 2–18 Bq/m{sup 3} and 70–1000 nSv/h, respectively. The annual effective dose was calculated and the average values was found to be 0.3 mSv which is below the 1 mSv limit. - Highlights: • Radiological assessment of groundwater treatment plant was performed. • Radium Removal efficiency was calculated for different stages during water treatment. • Radium concentrations in sludge were measured and found to exceed the national limit for radioactive waste. • Air radon concentrations and dose rates were monitored in the water treatment plant. • The Reverse Osmosis (RO) unit was found to record the highest air radon concentrations and dose rates.

  17. Guidance on Radon Resistant Construction and Radon Mitigation

    Science.gov (United States)

    This Unnumbered Letter regarding radon gas mitigation applies to all housing and community facilities, low-rise buildings and dwellings for the mentioned programs. Its intention is to guide staff to best serve our borrowers and protect their health.

  18. Extracellular Electron Transport Coupling Biogeochemical Processes Centimeters

    DEFF Research Database (Denmark)

    Risgaard-Petersen, Nils; Fossing, Henrik; Christensen, Peter Bondo

    2010-01-01

    Recent observations in marine sediment have revealed  conductive networks transmitting electrons from oxidation processes in the anoxic zone to oxygen reduction in the oxiczone [1]. The electrochemical processes and conductors seem to be biologically controlled and may account for more than half...... of the oxygen uptake in laboratory incubations of initially homogenized and stabilized sediment. Using microsensors and process rate measurements we further investigated the effect of the electric currents on sediment biogeochemistry. Dissolved sulfide readily donated electrons to the networks and could...... confirmed the depth range of the electric communication and indicated donation of electrons directly from organotrophic bacteria. The separation of oxidation and reduction processes created steep pH gradients eventually causing carbonate precipitation at the surface. The results indicate that electron...

  19. A finite volume solver for the simulation of transport processes

    NARCIS (Netherlands)

    Naifar, F.

    2006-01-01

    The simulation of the tracer transport process is an increasingly important tool to predict the distribution of pollution released in coastal waters. The equation that governs the tracer transport is the advection-diffusion equation. Thanks to the tremendous developments in computer resources and in

  20. Assessment of the overall effectiveness of the transport process

    Directory of Open Access Journals (Sweden)

    Radosavljević Dušan

    2017-01-01

    Full Text Available Achieving sustainable road transport requires the existence of methods for assessing its effectiveness, ie for assessing the overall efficiency of the transport process, road transport vehicles, vehicles and drivers. Transport companies and fleet companies for their own needs aim to increase the effectiveness of the resources they have and increase the quality of transport services in order to achieve a competitive position on the market. The achievement of the world class level in assessing the overall efficiency of the transport process is the goal of the state, the owner of the fleet, as well as the educational, professional and scientific community. The paper presents the importance of researching and managing the efficiency of the transport process, a literature review is presented, and a method for calculating the OVE Human indicators is presented, which is used as a tool for assessing the overall efficiency of the transport process, which can be corrected in the local environment. It was pointed out to the problems that were observed in the application of similar indicators and final conclusions were given.

  1. Development of a radon standard source

    Science.gov (United States)

    Sakamoto, Shigeyasu; Ishimori, Yuu; Maruo, Yoshihiro

    2005-06-01

    The present paper describes the development of a radon standard source for use in establishing the traceability of radon concentration measurements in air. Previously, radon generated by bubbling air through a radium salt solution was widely used for calibration of radon measurement equipment; however, the handling of a solid-phase radon source is easier. In the present study, the radioactivity of radon released in a vapor phase was determined from the difference between the radioactivity of the radium and the residual radon progenies in the source. A germanium detector, calibrated using gamma reference sources, was used for these radioactivity measurements. Under equilibrium conditions the radioactivity of the radon released from the radium source was found to be 988 Bq. The source was sealed in a stainless-steel container having a nominal capacity of 6 l to produce a radon standard source of density of 167.5 [Bq/l].

  2. The cost effectiveness of radon reduction programmes in domestic housing in England and Wales: the impact of improved radon mapping and housing trends.

    Science.gov (United States)

    Denman, A R; Sinclair, J; Phillips, P S; Crockett, R G M; Groves-Kirkby, C J

    2013-09-01

    In the UK, excessive levels of radon gas have been detected in domestic housing. Areas where 1% of existing homes were found to be over the Action Level of 200Bq·m(-3) were declared to be Radon Affected Areas. Building Regulations have been introduced which require that, for areas where between 3% and 10% of existing houses are above the Action Level, new homes should be built with basic radon protection using a membrane, and that, where 10% or more of existing homes exceed this level, new homes should be built with full radon protection. Initially these affected areas followed administrative boundaries, known as Counties. However, with increasing numbers of measurements of radon levels in domestic homes recorded in the national database, these areas have been successively refined into smaller units - 5km grid squares in 1999, down to 1km grid squares in 2007. One result is the identification of small areas with raised radon levels within regions where previously no problem had been identified. In addition, some parts of areas that were previously considered radon affected are now considered low, or no, risk. Our analysis suggests that the net result of improved mapping is to increase the number of affected houses. Further, the process is more complex for local builders, and inspectors, who need to work out whether radon protection in new homes is appropriate. Our group has assessed the cost-effectiveness of radon remediation programmes, and has applied this analysis to consider the cost-effectiveness of providing radon protection in both new and existing homes. This includes modelling the potential failure rate of membranes, and whether testing radon levels in new homes is appropriate. The analysis concludes that it is more cost effective to provide targeted radon protection in high radon areas, although this introduces more complexity. The paper also considers the trend in housing to a greater proportion of apartments, the regional variations in types of housing

  3. The impact of transport processes standardization on supply chain efficiency

    Directory of Open Access Journals (Sweden)

    Maciej Stajniak

    2016-03-01

    Full Text Available Background: During continuous market competition, focusing on the customer service level, lead times and supply flexibility is very important to analyze the efficiency of logistics processes. Analysis of supply chain efficiency is one of the fundamental elements of controlling analysis. Transport processes are a key process that provides physical material flow through the supply chain. Therefore, in this article Authors focus attention on the transport processes efficiency. Methods: The research carried out in the second half of 2014 year, in 210 enterprises of the Wielkopolska Region. Observations and business practice studies conducted by the authors, demonstrate a significant impact of standardization processes on supply chain efficiency. Based on the research results, have been developed standard processes that have been assessed as being necessary to standardize in business practice. Results: Based on these research results and observations, authors have developed standards for transport processes by BPMN notation. BPMN allows authors to conduct multivariate simulation of these processes in further stages of research. Conclusions: Developed standards are the initial stage of research conducted by Authors in the assessment of transport processes efficiency. Further research direction is to analyze the use efficiency of transport processes standards in business practice and their impact on the effectiveness of the entire supply chain.

  4. Divide and conquer: processive transport enables multidrug transporters to tackle challenging drugs

    Directory of Open Access Journals (Sweden)

    Nir Fluman

    2014-09-01

    Full Text Available Multidrug transporters are membrane proteins that catalyze efflux of antibiotics and other toxic compounds from cells, thereby conferring drug resistance on various organisms. Unlike most solute transporters that transport a single type of compound or similar analogues, multidrug transporters are extremely promiscuous. They transport a broad spectrum of dissimilar drugs and represent a serious obstacle to antimicrobial or anticancer chemotherapy. Many challenging aspects of multidrug transporters, which are unique, have been studied in detail, including their ability to interact with chemically unrelated drugs, and how they utilize energy to drive efflux of compounds that are not only structurally but electrically different. A new and surprising dimension of the promiscuous nature of multidrug transporters has been described recently: they can move long molecules through the membrane in a processive manner.

  5. 30 CFR 57.5046 - Protection against radon gas.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Protection against radon gas. 57.5046 Section... Protection against radon gas. Where radon daughter concentrations exceed 10 WL, respirator protection against radon gas shall be provided in addition to protection against radon daughters. Protection against radon...

  6. Radon risk in the house; Il rischio radon nelle abitazioni

    Energy Technology Data Exchange (ETDEWEB)

    Bressa, G. [Padua Univ., Padua (Italy). Dipt. di Farmacologia e Anestesiologia, Lab. di Tossicologia

    2001-04-01

    Radon was discovered in 1900, but its potential dangerousness for man was fully understood only in 1950. Being a radioactive natural gas - and therefore particularly dangerous - radon results from the long decay chain of radionuclides, such as thorium and radium. Some igneous rocks (granite, tufa and lava) as well as coal are considered to be the main sources of this radionuclide. A number of epidemiologic studies have shown the carcinogenicity of this element, particularly among miners and workers subjected to high level exposure in confined spaces such as basements, garages, cellars, etc. There are, however, some techniques to remove radon in order to reduce exposure to minimum values. [Italian] Il radon fu scoperto nel 1900, ma solo nel 1950 si comprese la sua potenziale pericolosita' per l'uomo. Il radon e' particolarmente pericoloso essendo un gas naturale radioattivo. Esso proviene dalla lunga catena di decadimento di radionuclidi come il torio e di radio. Sorgenti di tale radionuclide sono da considerarsi principalmente alcune rocce ignee (graniti, tufi e lave) e il carbone. Diversi studi epidemiologici hanno evidenziato la cancerogenicita' di tale elemento, specie tra i minatori e soggetti esposti ad alti livelli in ambienti confinati quali scantinati, garage sotterranei, ecc.. Esistono comunque tecniche di intervento per la rimozione del gas radon in modo tale da ridurre l'esposizione a valori minimi.

  7. Interfacial fluid dynamics and transport processes

    CERN Document Server

    Schwabe, Dietrich

    2003-01-01

    The present set of lectures and tutorial reviews deals with various topical aspects related to instabilities of interfacial processes and driven flows from both the theoretical and experimental point of views. New research has been spurred by the many demands for applications in material sciences (melting, solidification, electro deposition), biomedical engineering and processing in microgravity environments. This book is intended as both a modern source of reference for researchers in the field as well as an introduction to postgraduate students and non-specialists from related areas.

  8. Statewide and Metropolitan Transportation Planning Processes : a TPCB Peer Exchange

    Science.gov (United States)

    2016-04-20

    This report highlights key recommendations and noteworthy practices identified at Statewide and Metropolitan Transportation Planning Processes Peer Exchange held on September 9-10, 2015 in Shepherdstown, West Virginia. This event was sponsored ...

  9. Collecting duct principal cell transport processes and their regulation

    National Research Council Canada - National Science Library

    Pearce, D; Soundararajan, R; Trimpert, C; Kashlan, O.B; Deen, P.M.T; Kohan, D.E

    2015-01-01

    .... The effects of hormonal, autocrine, and paracrine factors to regulate principal cell transport processes are central to the maintenance of fluid and electrolyte balance in the face of wide variations...

  10. Soil gas radon measurements around Mt. Etna volcano in terms of evaluation of geodynamic events

    Science.gov (United States)

    Immè, Giuseppina; Catalano, Roberto; Giammanco, Salvatore; Ichedef, Mutlu; Neri, Marco; Morelli, Daniela; Murè, Filippo; Giudice, Nunzio

    2017-04-01

    Soil gas radon measurements were performed continuously in the east flank of Mt. Etna since July 2015 volcano in order to correlate soil gas radon anomalies with local geodynamic processes. Both volcanic activity and seismic monitoring have been carried out by means of seismic stations and video-cameras located around the volcano, while the evaluation of radon data has been done using basic statistics and signal processing methods. Preliminary analysis of data seems to indicate a clear correlation between soil gas radon variations and volcanic activity of Mt. Etna, being the November 2015 and May 2016 eruptions preceded by marked anomalous variations (mainly decreases) of radon levels in all monitoring stations. Further anomalies have been recognized since November 2016, which may suggest new arrival of fresh magma into the volcano, possibly leading to future eruptions.

  11. Damage costs due to bedload transport processes in Switzerland

    Science.gov (United States)

    Badoux, A.; Andres, N.; Turowski, J. M.

    2014-02-01

    In Alpine regions, floods are often associated with erosion, transport and deposition of coarse sediment along the streams. These processes are related to bedload transport and pose a hazard in addition to the elevated water discharge. However, it is unclear to what extent they contribute to total damage caused by natural hazards. Using the Swiss flood and landslide damage database - which collects financial damage data of naturally triggered floods, debris flows and landslides - we estimated the contribution of fluvial bedload transport processes to total damage costs in Switzerland. For each database entry an upper and lower limit of financial losses caused by or related to bedload transport processes was estimated, and the quality of the estimate was judged. When compared to total damage, the fraction of bedload transport damage in the 40 yr study period lies between 0.32 and 0.37. However, this value is highly variable for individual years (from 0.02 to 0.72). Bedload transport processes have induced cumulative financial losses between CHF 4.3 and 5.1 billion. Spatial analysis revealed a considerable heterogeneous distribution with largest damage for mountainous regions. The analysis of the seasonal distribution shows that more than 75 % of the bedload damage costs occurs in summer (June-August), and ∼ 23% in autumn (September-November). With roughly 56 %, by far most of the damage has been registered in August. Bedload transport processes are presently still inadequately understood, and the predictive quality of common bedload equations is often poor. Our analysis demonstrates the importance of bedload transport as a natural hazard and financial source of risk, and thus the need for future structured research on transport processes in steep streams.

  12. Effect of indoor-generated airborne particles on radon progeny dynamics

    Energy Technology Data Exchange (ETDEWEB)

    Trassierra, C. Vargas [Department of Civil and Mechanical Engineering, University of Cassino and Southern Lazio, Cassino, FR (Italy); Stabile, L., E-mail: l.stabile@unicas.it [Department of Civil and Mechanical Engineering, University of Cassino and Southern Lazio, Cassino, FR (Italy); Cardellini, F.; Morawska, L. [National Institute of Ionizing Radiation Metrology (INMRI-ENEA), Rome (Italy); Buonanno, G. [Department of Civil and Mechanical Engineering, University of Cassino and Southern Lazio, Cassino, FR (Italy); International Laboratory for Air Quality and Health, Queensland University of Technology, Brisbane (Australia)

    2016-08-15

    Highlights: • Investigation of the interaction between particles and radon progeny dynamics. • Measurements of particles emitted by different indoor sources. • Tests performed in a controlled radon chamber. • Particle size strongly influences the radon progeny dynamics. • Particle surface area concentration is the key parameter of the radon-particle interaction. - Abstract: In order to investigate the interaction between radon progeny and particles, an experimental campaign was carried out in a radon chamber at the Italian National Institute of Ionizing Radiation Metrology, quantifying the amount of attached and unattached radon daughters present in air, as well as the equilibrium factor in the presence of particles generated through indoor sources. A fixed radon concentration was maintained, while particles were generated using incense sticks, mosquito coils and gas combustion. Aerosols were characterized in terms of particle concentrations and size distributions. Simultaneously, radon concentration and attached/unattached potential alpha energy concentration in the air were continuously monitored by two different devices, based on alpha spectroscopy techniques. The presence of particles was found to affect the attached fraction of radon decay products, in such a way that the particles acted as a sink for radionuclides. In terms of sources which emit large particles (e.g. incense, mosquito coils), which greatly increase particle surface area concentrations, the Equilibrium Factor was found to double with respect to the background level before particle generation sessions. On the contrary, the radon decay product dynamics were not influenced by gas combustion processes, mainly due to the small surface area of the particles emitted.

  13. Evolution of radon dose evaluation

    Directory of Open Access Journals (Sweden)

    Fujimoto Kenzo

    2004-01-01

    Full Text Available The historical change of radon dose evaluation is reviewed based on the United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR reports. Since 1955, radon has been recognized as one of the important sources of exposure of the general public. However, it was not really understood that radon is the largest dose contributor until 1977 when a new concept of effective dose equivalent was introduced by International Commission on Radiological Protection. In 1982, the dose concept was also adapted by UNSCEAR and evaluated per caput dose from natural radiation. Many researches have been carried out since then. However, lots of questions have remained open in radon problems, such as the radiation weighting factor of 20 for alpha rays and the large discrepancy of risk estimation among dosimetric and epidemiological approaches.

  14. A Physician's Guide to Radon

    Science.gov (United States)

    This booklet has been developed for physicians by the U.S. Environmental Protection Agency in consultation with the American Medical Association (AMA). Its purpose is to enlist physicians in the national effort to inform the American public about radon.

  15. Radon measurements in schools: an interim report

    Energy Technology Data Exchange (ETDEWEB)

    1989-03-01

    The report provides school officials, groups such as Parent-Teacher Associations, and other interested person with interim information on how to measure radon in schools and what to do if elevated levels are found. The first sections of the document contain facts about radon and the health risks associated with radon exposure. The next sections summarize what is known about radon in schools and provide guidance for conducting radon measurements. The last sections describe how to interpret the measurement results and suggest techniques that can be used to reduce radon concentrations if elevated levels are found.

  16. Numerical modelling of radon-222 entry into houses: An outline of techniques and results

    DEFF Research Database (Denmark)

    Andersen, C.E.

    2001-01-01

    diffusive and advective transport of radon. Models of different complexity have been used. The simpler ones are finite-difference models with one or two spatial dimensions. The more complex models allow for full three-dimensional and time dependency. Advanced features include: soil heterogeneity, anisotropy......, fractures, moisture, non-uniform soil temperature, non-Darcy flow of gas, and flow caused by changes in the atmospheric pressure. Numerical models can be used to estimate the importance of specific factors for radon entry. Models are also helpful when results obtained in special laboratory or test structure....... As an illustrative example, radon entry is calculated for a standard slab-on-grade house....

  17. Intelligent Transportation Control based on Proactive Complex Event Processing

    Directory of Open Access Journals (Sweden)

    Wang Yongheng

    2016-01-01

    Full Text Available Complex Event Processing (CEP has become the key part of Internet of Things (IoT. Proactive CEP can predict future system states and execute some actions to avoid unwanted states which brings new hope to intelligent transportation control. In this paper, we propose a proactive CEP architecture and method for intelligent transportation control. Based on basic CEP technology and predictive analytic technology, a networked distributed Markov decision processes model with predicting states is proposed as sequential decision model. A Q-learning method is proposed for this model. The experimental evaluations show that this method works well when used to control congestion in in intelligent transportation systems.

  18. Association of School District Policies for Radon Testing and Radon-Resistant New Construction Practices with Indoor Radon Zones.

    Science.gov (United States)

    Foster, Stephanie; Everett Jones, Sherry

    2016-12-13

    Radon is a naturally occurring, colorless, odorless, and tasteless radioactive gas. Without testing, its presence is unknown. Using nationally representative data from the 2012 School Health Policies and Practices Study, we examined whether the prevalence of school district policies for radon testing and for radon-resistant new construction practices varied by district location in relation to the U.S. Environmental Protection Agency Map of Radon Zones. Among school districts located in counties with high predicted average indoor radon, 42.4% had policies for radon testing and 37.5% had policies for radon-resistant new construction practices. These findings suggest a critical need for improved awareness among policy makers regarding potential radon exposure for both students and school staff.

  19. Radon legislation and national guidelines

    Energy Technology Data Exchange (ETDEWEB)

    Aakerblom, G

    1999-07-01

    The International Commission on Radiological Protection (ICRP) and The Council of the European Union have recommended the Member States to take action against radon in homes and at workplaces. Within the EU project European Research into Radon in Construction Concerted Action, ERRICCA, the Topic Group on Legal and Building Code Impact was designated to study the current radon legislation and give advice regarding future enactment of laws and recommendations. On behalf of the Group, a questionnaire on radon legislation was sent out to nearly all European states and a selection of non-European states. Questions were asked regarding reference levels for dwellings, workplaces and drinking water, and about regulations or recommendations for building materials and city planning. All 15 EU Member States, 17 non-EU European countries and 10 non-European countries responded to the questionnaire. Their answers are considered current as of the end of 1998. Most European States and many non-European countries have recommended reference levels for dwellings and workplaces, and some have guidelines for measures against radon incorporated in their building codes and guidelines for construction techniques. However, only a few countries have enforced reference levels or regulations for planning and construction. The reference levels for indoor radon concentration in existing and new dwellings or workplaces are within the range 150-1000 Bq/m{sup 3}. Sweden is the only country (Out of 15 EU member states) which has enforced limits for existing dwellings. Sweden and the UK have both enforced levels for new dwellings. 7 non-European countries (Out of 17 responding countries) have enforced levels for existing dwellings and 9 have them for new dwellings. At the end of 1998, only Finland, Sweden, the Czech Republic, Romania, Russia and the Slovak Republic had limits for radon in water, although 8 countries were planning to introduce such limits. The present limits are within the range for

  20. Development of a predictive methodology for identifying high radon exhalation potential areas; Mise au point d'une methodologie predictive des zones a fort potentiel d'exhalation du radon

    Energy Technology Data Exchange (ETDEWEB)

    Ielsch, G

    2001-07-01

    Radon 222 is a radioactive natural gas originating from the decay of radium 226 which itself originates from the decay of uranium 23 8 naturally present in rocks and soil. Inhalation of radon gas and its decay products is a potential health risk for man. Radon can accumulate in confined environments such as buildings, and is responsible for one third of the total radiological exposure of the general public to radiation. The problem of how to manage this risk then arises. The main difficulty encountered is due to the large variability of exposure to radon across the country. A prediction needs to be made of areas with the highest density of buildings with high radon levels. Exposure to radon varies depending on the degree of confinement of the habitat, the lifestyle of the occupants and particularly emission of radon from the surface of the soil on which the building is built. The purpose of this thesis is to elaborate a methodology for determining areas presenting a high potential for radon exhalation at the surface of the soil. The methodology adopted is based on quantification of radon exhalation at the surface, starting from a precise characterization of the main local geological and pedological parameters that control the radon source and its transport to the ground/atmosphere interface. The methodology proposed is innovative in that it combines a cartographic analysis, parameters integrated into a Geographic Information system, and a simplified model for vertical transport of radon by diffusion through pores in the soil. This methodology has been validated on two typical areas, in different geological contexts, and gives forecasts that generally agree with field observations. This makes it possible to identify areas with a high exhalation potential within a range of a few square kilometers. (author)

  1. Association of School District Policies for Radon Testing and Radon-Resistant New Construction Practices with Indoor Radon Zones

    OpenAIRE

    Stephanie Foster; Sherry Everett Jones

    2016-01-01

    Radon is a naturally occurring, colorless, odorless, and tasteless radioactive gas. Without testing, its presence is unknown. Using nationally representative data from the 2012 School Health Policies and Practices Study, we examined whether the prevalence of school district policies for radon testing and for radon-resistant new construction practices varied by district location in relation to the U.S. Environmental Protection Agency Map of Radon Zones. Among school districts located in counti...

  2. Radon exposure at a radioactive waste storage facility.

    Science.gov (United States)

    Manocchi, F H; Campos, M P; Dellamano, J C; Silva, G M

    2014-06-01

    The Waste Management Department of Nuclear and Energy Research Institute (IPEN) is responsible for the safety management of the waste generated at all internal research centers and that of other waste producers such as industry, medical facilities, and universities in Brazil. These waste materials, after treatment, are placed in an interim storage facility. Among them are (226)Ra needles used in radiotherapy, siliceous cake arising from conversion processes, and several other classes of waste from the nuclear fuel cycle, which contain Ra-226 producing (222)Rn gas daughter.In order to estimate the effective dose for workers due to radon inhalation, the radon concentration at the storage facility has been assessed within this study. Radon measurements have been carried out through the passive method with solid-state nuclear track detectors (CR-39) over a period of nine months, changing detectors every month in order to determine the long-term average levels of indoor radon concentrations. The radon concentration results, covering the period from June 2012 to March 2013, varied from 0.55 ± 0.05 to 5.19 ± 0.45 kBq m(-3). The effective dose due to (222)Rn inhalation was further assessed following ICRP Publication 65.

  3. Earthquake forecasting studies using radon time series data in Taiwan

    Science.gov (United States)

    Walia, Vivek; Kumar, Arvind; Fu, Ching-Chou; Lin, Shih-Jung; Chou, Kuang-Wu; Wen, Kuo-Liang; Chen, Cheng-Hong

    2017-04-01

    For few decades, growing number of studies have shown usefulness of data in the field of seismogeochemistry interpreted as geochemical precursory signals for impending earthquakes and radon is idendified to be as one of the most reliable geochemical precursor. Radon is recognized as short-term precursor and is being monitored in many countries. This study is aimed at developing an effective earthquake forecasting system by inspecting long term radon time series data. The data is obtained from a network of radon monitoring stations eastblished along different faults of Taiwan. The continuous time series radon data for earthquake studies have been recorded and some significant variations associated with strong earthquakes have been observed. The data is also examined to evaluate earthquake precursory signals against environmental factors. An automated real-time database operating system has been developed recently to improve the data processing for earthquake precursory studies. In addition, the study is aimed at the appraisal and filtrations of these environmental parameters, in order to create a real-time database that helps our earthquake precursory study. In recent years, automatic operating real-time database has been developed using R, an open source programming language, to carry out statistical computation on the data. To integrate our data with our working procedure, we use the popular and famous open source web application solution, AMP (Apache, MySQL, and PHP), creating a website that could effectively show and help us manage the real-time database.

  4. The use of volunteer radon measurements for radon mapping purposes: an examination of sampling bias issues.

    Science.gov (United States)

    Burke, Orlaith; Murphy, Patrick

    2011-09-01

    National and regional radon surveys are used in many nations to produce maps detailing the spatial variation of indoor radon concentrations. National surveys which are designed to be representative use either a geographically-weighted or a population-weighted sampling scheme. Additionally, many countries collect a large number of data on indoor radon concentrations from volunteers who have chosen to have the indoor radon concentration measured in their own dwellings. This work examines the representativeness of volunteer-based samples in radon measurement and explores the effect of potential volunteer bias on radon mapping results. We also investigate the influence that media attention has on volunteer sampling of indoor radon concentrations. The result of our work indicates that volunteer measurements are biased due to over-sampling of high radon areas. Consequently such volunteer radon measurements should not be used for radon mapping purposes.

  5. Indoor radon, geogenic radon surrogates and geology - Investigations on their correlation.

    Science.gov (United States)

    Friedmann, H; Baumgartner, A; Bernreiter, M; Gräser, J; Gruber, V; Kabrt, F; Kaineder, H; Maringer, F J; Ringer, W; Seidel, C; Wurm, G

    2017-01-01

    The indoor radon concentration was measured in most houses in a couple of municipalities in Austria. At the same time the activity concentration of radium in soil, the soil gas radon concentration, the permeability of the ground and the ambient dose equivalent rate were also measured and the geological situations (geological units) were recorded too. From the indoor radon concentration and different house and living parameters a radon potential (Austrian radon potential) was derived which should represent the radon concentration in a standard room. Another radon potential (Neznal radon potential) was calculated from the soil gas radon concentration and the permeability. The aim of the investigation was to correlate all the different variables and to test if the use of surrogate data (e.g. geological information, ambient dose equivalent rate, etc.) can be used to judge the radon risk for an area without performing numerous indoor measurements. Copyright © 2016 Elsevier Ltd. All rights reserved.

  6. Elucidating the Role of Transport Processes in Leaf Glucosinolate Distribution

    DEFF Research Database (Denmark)

    Madsen, Svend Roesen; Olsen, Carl Erik; Nour-Eldin, Hussam Hassan

    2014-01-01

    In Arabidopsis (Arabidopsis thaliana), a strategy to defend its leaves against herbivores is to accumulate glucosinolates along the midrib and at the margin. Although it is generally assumed that glucosinolates are synthesized along the vasculature in an Arabidopsis leaf, thereby suggesting...... that the margin accumulation is established through transport, little is known about these transport processes. Here, we show through leaf apoplastic fluid analysis and glucosinolate feeding experiments that two glucosinolate transporters, GTR1 and GTR2, essential for long-distance transport of glucosinolates...... in Arabidopsis, also play key roles in glucosinolate allocation within a mature leaf by effectively importing apoplastically localized glucosinolates into appropriate cells. Detection of glucosinolates in root xylem sap unambiguously shows that this transport route is involved in root-to-shoot glucosinolate...

  7. Role of Passive Diffusion, Transporters, and Membrane Trafficking-Mediated Processes in Cellular Drug Transport.

    Science.gov (United States)

    Cocucci, E; Kim, J Y; Bai, Y; Pabla, N

    2017-01-01

    Intracellular drug accumulation is thought to be dictated by two major processes, passive diffusion through the lipid membrane or membrane transporters. The relative role played by these distinct processes remains actively debated. Moreover, the role of membrane-trafficking in drug transport remains underappreciated and unexplored. Here we discuss the distinct processes involved in cellular drug distribution and propose that better experimental models are required to elucidate the differential contributions of various processes in intracellular drug accumulation. © 2016 American Society for Clinical Pharmacology and Therapeutics.

  8. Mathematical Model of Ion Transport in Electrodialysis Process

    Directory of Open Access Journals (Sweden)

    F.S. Rohman

    2010-10-01

    Full Text Available Mathematical models of ion transport in electrodialysis process is reviewed and their basics concept is discussed. Three scales of ion transport reviewed are: 1 ion transport in the membrane, where two approaches are used, the irreversible thermodynamics and modeling of the membrane material; 2 ion transport in a three-layer system composed of a membrane with two adjoining diffusion layers; and 3 coupling with hydraulic flow system in an electrodialysis 2D and 3D cell, where the differential equation of convectivediffusion is used. Most of the work carried out in the past implemented NP equations since relatively easily coupled with other equations describing hydrodynamic conditions and ion transport in the surrounding solutions, chemical reactions in the solutions and the membrane, boundary and other conditions. However, it is limited to point ionic transport in homogenous and uniformly - grainy phases of structure. © 2008 BCREC UNDIP. All rights reserved.[Received: 21 January 2008, Accepted: 10 March 2008][How to Cite: F.S. Rohman, N. Aziz (2008. Mathematical Model of Ion Transport in Electrodialysis Process. Bulletin of Chemical Reaction Engineering and Catalysis, 3(1-3: 3-8. doi:10.9767/bcrec.3.1-3.7122.3-8][How to Link/DOI: http://dx.doi.org/10.9767/bcrec.3.1-3.7122.3-8 || or local: http://ejournal.undip.ac.id/index.php/bcrec/article/view/7122 ] 

  9. Mathematical Model of Ion Transport in Electrodialysis Process

    Directory of Open Access Journals (Sweden)

    F. S. Rohman

    2008-04-01

    Full Text Available Mathematical models of ion transport in electrodialysis process is reviewed and their basics concept is discussed.Three scales of ion transport reviewed are: 1 ion transport in the membrane, where two approachesare used, the irreversible thermodynamics and modeling of the membrane material; 2 ion transport in athree-layer system composed of a membrane with two adjoining diffusion layers; and 3 coupling with hydraulicflow system in an electrodialysis 2D and 3D cell, where the differential equation of convectivediffusionis used. Most of the work carried out in the past implemented NP equations since relatively easilycoupled with other equations describing hydrodynamic conditions and ion transport in the surrounding solutions,chemical reactions in the solutions and the membrane, boundary and other conditions. However, itis limited to point ionic transport in homogenous and uniformly - grainy phases of structure.© 2008 BCREC UNDIP. All rights reserved.[Received: 21 January 2008, Accepted: 10 March 2008][How to Cite: F.S. Rohman, N. Aziz (2008. Mathematical Model of Ion Transport in Electrodialysis Process. Bulletin of Chemical Reaction Engineering and Catalysis, 3(1-3: 3-8. doi:10.9767/bcrec.3.1-3.16.3-8

  10. Recent topics on radon. Radiation dose estimation using radon

    Energy Technology Data Exchange (ETDEWEB)

    Shimo, Michikuni [National Inst. of Radiological Sciences, Chiba (Japan)

    1998-05-01

    Today, as exposure of radon was collected a large interest in resident environment, it was brought by a fact that yearly radiation dose of radon was determined 1.0 mSv in the report of UN science committee in 1982. Since then, as this value was received generally and widely, this value was found some differences due to thereafter UN science committee reports and to some countings. As not only concentration of radon but also some factors relate to its cause, it is important to know its cause and variation width. In this paper, by using the newest data in Japan on radon concentration, balance factor, presence time, respiration volume, and so forth as much as possible, an effective radiation dose of an adult per year was estimated. As a result, it was found to be about 0.45 mSv, which was more than a half less than the value of the UN science committee and so on. And, this was nearly equal to that of workers at 3 prefectures of that Tokai District and counted by using radon concentration, respiration volume and presence coefficient for variants. On counting the whole variation width under considering width of each coefficient, it can be estimated to be ranged from -70 to +80%. (G.K.)

  11. Particle Tracking Model and Abstraction of Transport Processes

    Energy Technology Data Exchange (ETDEWEB)

    B. Robinson

    2000-04-07

    The purpose of the transport methodology and component analysis is to provide the numerical methods for simulating radionuclide transport and model setup for transport in the unsaturated zone (UZ) site-scale model. The particle-tracking method of simulating radionuclide transport is incorporated into the FEHM computer code and the resulting changes in the FEHM code are to be submitted to the software configuration management system. This Analysis and Model Report (AMR) outlines the assumptions, design, and testing of a model for calculating radionuclide transport in the unsaturated zone at Yucca Mountain. In addition, methods for determining colloid-facilitated transport parameters are outlined for use in the Total System Performance Assessment (TSPA) analyses. Concurrently, process-level flow model calculations are being carrier out in a PMR for the unsaturated zone. The computer code TOUGH2 is being used to generate three-dimensional, dual-permeability flow fields, that are supplied to the Performance Assessment group for subsequent transport simulations. These flow fields are converted to input files compatible with the FEHM code, which for this application simulates radionuclide transport using the particle-tracking algorithm outlined in this AMR. Therefore, this AMR establishes the numerical method and demonstrates the use of the model, but the specific breakthrough curves presented do not necessarily represent the behavior of the Yucca Mountain unsaturated zone.

  12. A fast butterfly algorithm for generalized Radon transforms

    KAUST Repository

    Hu, Jingwei

    2013-06-21

    Generalized Radon transforms, such as the hyperbolic Radon transform, cannot be implemented as efficiently in the frequency domain as convolutions, thus limiting their use in seismic data processing. We have devised a fast butterfly algorithm for the hyperbolic Radon transform. The basic idea is to reformulate the transform as an oscillatory integral operator and to construct a blockwise lowrank approximation of the kernel function. The overall structure follows the Fourier integral operator butterfly algorithm. For 2D data, the algorithm runs in complexity O(N2 log N), where N depends on the maximum frequency and offset in the data set and the range of parameters (intercept time and slowness) in the model space. From a series of studies, we found that this algorithm can be significantly more efficient than the conventional time-domain integration. © 2013 Society of Exploration Geophysicists.

  13. 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

  14. Comparison of radon doses based on different radon monitoring approaches.

    Science.gov (United States)

    Vaupotič, Janja; Smrekar, Nataša; Žunić, Zora S

    2017-04-01

    In 43 places (23 schools, 3 kindergartens, 16 offices and one dwelling), indoor radon has been monitored as an intercomparison experiment, using α-scintillation cells (SC - Jožef Stefan Institute, Slovenia), various kinds of solid state nuclear track detectors (KfK - Karlsruhe Institute of Technology, Germany; UFO - National Institute of Radiological Sciences, Chiba, Japan; RET - University College Dublin, Ireland) and active electronic devices (EQF, Sarad, Germany). At the same place, the radon levels and, consequently, the effective doses obtained with different radon devices differed substantially (by a factor of 2 or more), and no regularity was observed as regards which detector would show a higher or lower dose. Copyright © 2016 Elsevier Ltd. All rights reserved.

  15. A Radon Progeny Deposition Model

    Science.gov (United States)

    Guiseppe, V. E.; Elliott, S. R.; Hime, A.; Rielage, K.; Westerdale, S.

    2011-04-01

    The next generation low-background detectors operating underground aim for unprecedented low levels of radioactive backgrounds. Although the radioactive decays of airborne radon (particularly 222Rn) and its subsequent progeny present in an experiment are potential backgrounds, also problematic is the deposition of radon progeny on detector materials. Exposure to radon at any stage of assembly of an experiment can result in surface contamination by progeny supported by the long half life (22 y) of 210Pb on sensitive locations of a detector. An understanding of the potential surface contamination from deposition will enable requirements of radon-reduced air and clean room environments for the assembly of low background experiments. It is known that there are a number of environmental factors that govern the deposition of progeny onto surfaces. However, existing models have not explored the impact of some environmental factors important for low background experiments. A test stand has been constructed to deposit radon progeny on various surfaces under a controlled environment in order to develop a deposition model. Results from this test stand and the resulting deposition model are presented.

  16. Description of the behavior of an aquifer by using continuous radon monitoring in a thermal spa.

    Science.gov (United States)

    Sainz, Carlos; Rábago, Daniel; Fuente, Ismael; Celaya, Santiago; Quindós, Luis Santiago

    2016-02-01

    Radon ((222)Rn) levels in air and water have been analyzed continuously for almost a year in Las Caldas de Besaya thermal spa, north Spain. Radon is a naturally occurring noble gas from the decay of radium ((226)Ra) both constituents of radioactive uranium 238 series. It has been recognized as a lung carcinogen by the World Health Organization (WHO) and International Agency for Research on Cancer (IARC). Furthermore the Royal Decree R.D 1439/2010 of November, 2010 establishes the obligation to study occupational activities where workers and, where appropriate, members of the public are exposed to inhalation of radon in workplaces such as spas. Together with radon measures several physico-chemical parameters were obtained such as pH, redox potential, electrical conductivity and air and water temperature. The devices used for the study of the temporal evolution of radon concentration have been the RTM 2100, the Radon Scout and gamma spectrometry was complementarily used to determine the transfer factor of the silicone tubes in the experimental device. Radon concentrations obtained in water and air of the spa are high, with an average of 660 Bq/l and 2900 Bq/m(3) respectively, where water is the main source of radon in the air. Radiation dose for workers and public was estimated from these levels of radon. The data showed that the thermal processes can control the behavior of radon which can be also influenced by various physical and chemical parameters such as pH and redox potential. Copyright © 2015 Elsevier B.V. All rights reserved.

  17. Gathering Information from Transport Systems for Processing in Supply Chains

    Science.gov (United States)

    Kodym, Oldřich; Unucka, Jakub

    2016-12-01

    Paper deals with complex system for processing information from means of transport acting as parts of train (rail or road). It focuses on automated information gathering using AutoID technology, information transmission via Internet of Things networks and information usage in information systems of logistic firms for support of selected processes on MES and ERP levels. Different kinds of gathered information from whole transport chain are discussed. Compliance with existing standards is mentioned. Security of information in full life cycle is integral part of presented system. Design of fully equipped system based on synthesized functional nodes is presented.

  18. Radon exhalation studies in building materials using solid-state ...

    Indian Academy of Sciences (India)

    Inhalation of 222Rn and its daughter products, especially 218Po and 214Po attached to aerosols present in ambient air, causes significant radiological hazard to human lungs. Radon appears mainly by diffusion processes from the point of origin, following a-decay of 226Ra in underground soil and building materials used.

  19. CONSEQUENCES OF USING HOME-MADE RADON SOURCES FOR MEASURING THE RADON DIFFUSION COEFFICIENT.

    Science.gov (United States)

    Dobrovolný, T; Jiránek, M

    2017-11-01

    The applicability of home-made radon sources for determining the radon diffusion coefficient of waterproofing materials was studied for three representatives of materials with a high radium content: uraninite, slag concrete and filter sand. The results of our investigation confirmed that the radon production rate of home-made radon sources is significantly lower than the radon production rate of artificial sources. Consequently, home-made sources are usually unable to generate concentrations higher than 100 kBq/m3 in the source container. Therefore, they cannot be used for determining radon diffusion coefficients lower than 1 × 10-12 m2/s. In addition, when home-made radon sources are used, only time-dependent mathematical solutions of the non-stationary radon diffusion can be used for determining the radon diffusion coefficient from the measured data. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  20. Radon activity in Saudi houses

    Energy Technology Data Exchange (ETDEWEB)

    Abu-Jarad, F.; Al-Jarallah, M.I. (University of Petroleum and Minerals, Dhahran (Saudi Arabia). Dept. of Physics)

    1984-01-01

    Long term measurements of radon's concentrations inside Saudi houses being studied using CR-39 Plastic Track Detectors fixed inside sealed plastic cups. The cups were left for about 7 months in the houses. The measurements were done in different cities of different provinces in the country. The analysis of 636 cups showed that the radon concentration in different cities was ranging from 0.27 pCi/l (in Khobar) to 0.98 pCi/l (in Taif). In exceptional places in Eastern Province, it is found that the lowest concentration was in the University offices (0.13 pCi/l) and the highest was in the University unoccupied houses (0.81 pCi/l). It is found that the ventilation is the main factor affecting the radon concentration in houses.

  1. Thermo-diffusional radon waves in soils

    Energy Technology Data Exchange (ETDEWEB)

    Minkin, Leonid, E-mail: lminkin@pcc.edu [Portland Community College, 12000 SW 49th Ave, Portland, OR 97219 (United States); Shapovalov, Alexander S. [Saratov State University, 83 Astrakhanskay Street, Saratov 410012 (Russian Federation)

    2016-09-15

    A new theoretical framework for diurnal and seasonal oscillations of the concentration of radon in soil and open air is proposed. The theory is based on the existing temperature waves in soils and thermo-diffusional gas flux in porous media. As soil is a non-isothermal porous medium, usually possessing a large fraction of microscopic pores belonging to Knudsen's free molecular field, a thermo-diffusional gas flow in soil has to arise. The radon mass transfer equation in soil for sinusoidal temperature oscillations at the soil–atmosphere boundary is solved, which reveals that radon concentration behaves as a damped harmonic wave. The amplitude of radon concentration oscillations and phase shift between radon concentration oscillations and soil temperature depend on the radon diffusion coefficient in soil, rate of radon production, soil thermal conductivity, average soil temperature, decay constant, and heat of radon transfer. Primarily numerical calculations are presented and comparisons with experimental data are shown. - Highlights: • Temperature oscillations in atmosphere generate radon waves in soil. • Radon flux in atmosphere is a harmonic function of time. • Radon concentration waves in soil have the same frequency as the temperature waves.

  2. Power-Law Radon-Transformed Superimposed Inverse Filter Synthetic Discriminant Correlator for Facial Recognition

    National Research Council Canada - National Science Library

    Haji-saeed, Bahareh; Khoury, Jed; Woods, Charles L; Kierstead, John

    2008-01-01

    ...) for facial recognition is proposed. In order to avoid spectral overlap and nonlinear crosstalk, superposition of rotationally variant sets of inverse filter Fourier-transformed Radon-processed templates is used to generate the SDF...

  3. Transportation informatics : advanced image processing techniques automated pavement distress evaluation.

    Science.gov (United States)

    2010-01-01

    The current project, funded by MIOH-UTC for the period 1/1/2009- 4/30/2010, is concerned : with the development of the framework for a transportation facility inspection system using : advanced image processing techniques. The focus of this study is ...

  4. Radon og lungekreft i Norge

    OpenAIRE

    Enger, Ingvild-M.A

    2011-01-01

    Sammendrag Denne masteroppgaven ”Radon og lungekreft i Norge” inneholder to deler; den første delen inneholder en introduksjon til studien med utdypende empiri og teori i en større sammenheng. Den andre delen er artikkelen ” Sammenhengen mellom forekomst av lungekreft og radon målt i bolig hus – en økologisk studie”. Siste del skal sendes til Tidsskriftet for Den norske legeforening for publisering. Formålet med denne studien var å undersøke om det var høyere forekomst av lungekreft bla...

  5. Transient radon signals driven by fluid pressure pulse, micro-crack closure, and failure during granite deformation experiments

    Science.gov (United States)

    Girault, Frédéric; Schubnel, Alexandre; Pili, Éric

    2017-09-01

    In seismically active fault zones, various crustal fluids including gases are released at the surface. Radon-222, a radioactive gas naturally produced in rocks, is used in volcanic and tectonic contexts to illuminate crustal deformation or earthquake mechanisms. At some locations, intriguing radon signals have been recorded before, during, or after tectonic events, but such observations remain controversial, mainly because physical characterization of potential radon anomalies from the upper crust is lacking. Here we conducted several month-long deformation experiments under controlled dry upper crustal conditions with a triaxial cell to continuously monitor radon emission from crustal rocks affected by three main effects: a fluid pressure pulse, micro-crack closure, and differential stress increase to macroscopic failure. We found that these effects are systematically associated with a variety of radon signals that can be explained using a first-order advective model of radon transport. First, connection to a source of deep fluid pressure (a fluid pressure pulse) is associated with a large transient radon emission increase (factor of 3-7) compared with the background level. We reason that peak amplitude is governed by the accumulation time and the radon source term, and that peak duration is controlled by radioactive decay, permeability, and advective losses of radon. Second, increasing isostatic compression is first accompanied by an increase in radon emission followed by a decrease beyond a critical pressure representing the depth below which crack closure hampers radon emission (150-250 MPa, ca. 5.5-9.5 km depth in our experiments). Third, the increase of differential stress, and associated shear and volumetric deformation, systematically triggers significant radon peaks (ca. 25-350% above background level) before macroscopic failure, by connecting isolated cracks, which dramatically enhances permeability. The detection of transient radon signals before rupture

  6. Development of a highly sensitive radon-222 amplifier (HiSRA) for low-level atmospheric measurements.

    Science.gov (United States)

    Topin, Sylvain; Richon, Patrick; Thomas, Vincent; Gréau, Claire; Pujos, Julie; Moulin, Julien; Hovesepian, Alexandre; Deliere, Ludovic

    2017-05-01

    Radon ((222)Rn), a radioactive gas with a half-life of 3.82 days, is continuously emanated from soil, rocks, and water by the radioactive decay of (226)Ra. Radon-222 is released from the ground into the atmosphere, where it is transported mainly by turbulent diffusion or convection. For precise measurement of radon-222 atoms in the atmosphere, the detectors typically used present a small volume or surface area and are therefore not very sensitive, especially for online measurements and short sample intervals (Radon Amplifier (HiSRA) consisting in an enrichment system placed prior to a classic radon-222 analyzer. This system uses permeation membranes that make it possible to treat large quantities of air online (30 m(3) h(-1)). The radon-222 concentration is increased instantaneously by at least a factor of 30 across the HiSRA system. Therefore, in this study, when coupling to an ionization chamber (AlphaGUARDTM) at the outlet of the HiSRA system, the detection limit of the overall system is multiplied by factor of 30 and induces a new LD for a radon 222 gas analyzer lower than 1 Bq m(-3) for an integrating time of 10 min and 0.1 Bq m(-3) for 1 h. We constructed one radon amplifier prototype that provided the preliminary results for amplification efficiency and the initial measurements presented herein. Copyright © 2017 Elsevier Ltd. All rights reserved.

  7. Features, Events, and Processes in UZ Flow and Transport

    Energy Technology Data Exchange (ETDEWEB)

    J.E. Houseworth

    2001-04-10

    Unsaturated zone (UZ) flow and radionuclide transport is a component of the natural barriers that affects potential repository performance. The total system performance assessment (TSPA) model, and underlying process models, of this natural barrier component capture some, but not all, of the associated features, events, and processes (FEPs) as identified in the FEPs Database (Freeze, et al. 2001 [154365]). This analysis and model report (AMR) discusses all FEPs identified as associated with UZ flow and radionuclide transport. The purpose of this analysis is to give a comprehensive summary of all UZ flow and radionuclide transport FEPs and their treatment in, or exclusion from, TSPA models. The scope of this analysis is to provide a summary of the FEPs associated with the UZ flow and radionuclide transport and to provide a reference roadmap to other documentation where detailed discussions of these FEPs, treated explicitly in TSPA models, are offered. Other FEPs may be screened out from treatment in TSPA by direct regulatory exclusion or through arguments concerning low probability and/or low consequence of the FEPs on potential repository performance. Arguments for exclusion of FEPs are presented in this analysis. Exclusion of specific FEPs from the UZ flow and transport models does not necessarily imply that the FEP is excluded from the TSPA. Similarly, in the treatment of included FEPs, only the way in which the FEPs are included in the UZ flow and transport models is discussed in this document. This report has been prepared in accordance with the technical work plan for the unsaturated zone subproduct element (CRWMS M&O 2000 [153447]). The purpose of this report is to document that all FEPs are either included in UZ flow and transport models for TSPA, or can be excluded from UZ flow and transport models for TSPA on the basis of low probability or low consequence. Arguments for exclusion are presented in this analysis. Exclusion of specific FEPs from UZ flow and

  8. 76 FR 72006 - Draft Interim Staff Guidance: Evaluations of Uranium Recovery Facility Surveys of Radon and Radon...

    Science.gov (United States)

    2011-11-21

    ... COMMISSION Draft Interim Staff Guidance: Evaluations of Uranium Recovery Facility Surveys of Radon and Radon... Recovery Facility Surveys of Radon and Radon Progeny in Air and Demonstrations of Compliance with 10 CFR 20... that existing guidance does not sufficiently detail how the NRC staff reviews surveys of radon and...

  9. Analysis of Transport Processes Management for a Romanian Food Market

    Directory of Open Access Journals (Sweden)

    Maria NEAGU

    2012-12-01

    Full Text Available This paper presents the study of optimization process for the products transportation for a Romanian food-market. The vehicle routing problem was solves using Lingo 13.0 software and an analysis was conducted in order to determine the optimal routes for the vehicles in the conditions of products request variation. The program developed is considering one storing place from where the products are transported to other six delivery points using three vehicles. Each vehicle has a constant capacity and a constant travel velocity.

  10. The rate-limiting process of hydrogen transport in Mo

    Energy Technology Data Exchange (ETDEWEB)

    Ohkoshi, Keishiro; Chikazawa, Yoshitaka; Bandourko, V.; Yamaguchi, Kenji; Yamawaki, Michio [Tokyo Univ., Tokai, Ibaraki (Japan). Nuclear Engineering Research Lab.

    1996-10-01

    Hydrogen isotope transport characteristics of Mo, whose refractory properties are considered to be suitable as plasma facing material, was investigated by applying 3 keV D{sub 2}{sup +} beam to the membrane specimen. The Arrhenius plot of deuterium permeation probability showed linear increase against the reciprocal temperature and its apparent activation energy was determined as 41.5 kJ/mol. The simultaneous irradiation of 3 keV Ar{sup +} onto backside surface of specimen had little effect on the deuterium permeation rate. According to these results, the rate-limiting process of deuterium transport in Mo was determined. (author)

  11. Correlated receptor transport processes buffer single-cell heterogeneity.

    Directory of Open Access Journals (Sweden)

    Stefan M Kallenberger

    2017-09-01

    Full Text Available Cells typically vary in their response to extracellular ligands. Receptor transport processes modulate ligand-receptor induced signal transduction and impact the variability in cellular responses. Here, we quantitatively characterized cellular variability in erythropoietin receptor (EpoR trafficking at the single-cell level based on live-cell imaging and mathematical modeling. Using ensembles of single-cell mathematical models reduced parameter uncertainties and showed that rapid EpoR turnover, transport of internalized EpoR back to the plasma membrane, and degradation of Epo-EpoR complexes were essential for receptor trafficking. EpoR trafficking dynamics in adherent H838 lung cancer cells closely resembled the dynamics previously characterized by mathematical modeling in suspension cells, indicating that dynamic properties of the EpoR system are widely conserved. Receptor transport processes differed by one order of magnitude between individual cells. However, the concentration of activated Epo-EpoR complexes was less variable due to the correlated kinetics of opposing transport processes acting as a buffering system.

  12. Residential radon in Galicia: a cross-sectional study in a radon-prone area.

    Science.gov (United States)

    Lorenzo-González, María; Ruano-Ravina, Alberto; Peón, Joaquín; Piñeiro, María; Barros-Dios, Juan Miguel

    2017-09-01

    Residential radon exposure is a major public health problem. It is the second greatest cause of lung cancer, after smoking, and the greatest in never-smokers. This study shows the indoor radon exposure distribution in Galicia and estimates the percentage of dwellings exceeding reference levels. It is based on 3245 residential radon measurements obtained from the Galician Radon Map project and from controls of two previous case-control studies on residential radon and lung cancer. Results show a high median residential radon concentration in Galicia (99 Bq m -3 ), with 49.3% of dwellings having a radon concentration above 100 Bq m -3 and 11.1% having a concentration above 300 Bq m -3 . Ourense and Pontevedra, located in South Galicia, are the provinces with the highest median indoor radon concentrations (137 Bq m -3 and 123.5 Bq m -3 , respectively). Results also show lower radon levels in progressively higher building storeys. These high residential radon concentrations confirm Galicia as a radon-prone area. A policy on radon should be developed and implemented in Galicia to minimize the residential radon exposure of the population.

  13. Homogenity of geological units with respect to the radon risk in the Walloon region of Belgium.

    Science.gov (United States)

    Tondeur, François; Cinelli, Giorgia; Dehandschutter, Boris

    2014-10-01

    In the process of mapping indoor radon risk, an important step is to define geological units well-correlated with indoor radon. The present paper examines this question for the Walloon region of Belgium, using a database of more than 18,000 indoor radon measurements. With a few exceptions like the Carboniferous (to be divided into Tournaisian, Visean and Namurian-Westphalian) and the Tertiary (in which all Series may be treated together), the Series/Epoch stratigraphic level is found to be the most appropriate geological unit to classify the radon risk. A further division according to the geological massif or region is necessary to define units with a reasonable uniformity of the radon risk. In particular, Paleozoic series from Cambrian to Devonian show strong differences between different massifs. Local hot-spots are also observed in the Brabant massif. Finally, 35 geological units are defined according to their radon risk, 6 of which still present a clear weak homogeneity. In the case of 4 of these units (Jurassic, Middle Devonian of Condroz and of Fagne-Famenne, Ordovician of the Stavelot massif) homogeneity is moderate, but the data are strongly inhomogeneous for Visean in Condroz and in the Brabant massif. The 35 geological units are used in an ANOVA analysis, to evaluate the part of indoor radon variability which can be attributed to geology. The result (15.4-17.7%) agrees with the values observed in the UK. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.

  14. Recent achievements in facilitated transport membranes for separation processes

    Directory of Open Access Journals (Sweden)

    H. C. Ferraz

    2007-03-01

    Full Text Available Membrane separation processes have been extensively used for some important industrial separations, substituting traditional methods. However, some applications require the development of new membranes. In this work, we discuss recent progress achieved in this field, focusing on gas and liquid separation using facilitated transport membranes. The advantages of using a carrier species either in a liquid membrane or fixed in a polymer matrix to enhance both the flux and the selectivity of the transport are summarized. The most probable transport mechanisms in these membranes are presented and the improvements needed to spread this technology are also discussed. As examples, we discuss our very successful experiences in air fractioning, olefin/paraffin separation and sugar recovery using liquid and fixed carrier membranes.

  15. Review of modeling and control during transport airdrop process

    Directory of Open Access Journals (Sweden)

    Bin Xu

    2016-12-01

    Full Text Available This article presents the review of modeling and control during the airdrop process of transport aircraft. According to the airdrop height, technology can be classified into high and low altitude airdrop and in this article, the research is reviewed based on the two scenarios. While high altitude airdrop is mainly focusing on the precise landing control of cargo, the low altitude flight airdrop is on the control of transport aircraft dynamics to ensure flight safety. The history of high precision airdrop system is introduced first, and then the modeling and control problem of the ultra low altitude airdrop in transport aircraft is presented. Finally, the potential problems and future direction of low altitude airdrop are discussed.

  16. Scaling and predicting solute transport processes in riverine ecosystems

    Science.gov (United States)

    Gonzalez-Pinzon, R.; Haggerty, R.; Camacho Botero, L. A.

    2012-12-01

    In the last three decades, research on solute transport and nutrient processing has revealed complex interactions between landscapes and stream ecosystems, and numerous attempts to scale and predict these processes have been primarily limited by the difficulty of measuring and extrapolating hydrodynamic and geomorphic characteristics. We hypothesize that there should be predictable patterns in the way that streams interact with their landscapes, because those interactions are in the form of energy, mass and momentum, which are conservative and interrelated properties. Therefore, despite local hydrogeomorphic characteristics define the actual extent of solute transport processes in a given riverine ecosystem, the physical imprints marked-up in breakthrough curves (BTCs) should have scaling properties. To evaluate our hypothesis we created an extensive database that includes 133 BTCs from conservative tracer experiments conducted under different hydrologic conditions (1 lt/s to 1197 m3/s), different experimental conditions (10s of meters to 10s of kilometers), different geographic positions (South and North America, Europe, Australia, Antarctica), and different types of lotic environments, i.e., urban manmade channels, forested headwater streams, desert-like streams, hyporheic wells, and major rivers. We investigated the existence of patterns in conservative solute transport using a model-independent approach, i.e., temporal moments of the histories of tracer experiments. Our results show that the normalized first absolute moment is correlated with the second and third moments with R2>0.99 for all riverine ecosystems. Most importantly, the first central temporal moment of the distributions (mean travel time) is correlated with the second (variance) with an R2>0.93, and the correlation between the second central moment and the third central moment (skewness) takes the form of the coefficient of skewness (CSK) with an R2>0.98, defining a statistically averaged CSK= 1

  17. Process-based modeling of tsunami inundation and sediment transport

    Science.gov (United States)

    Apotsos, A.; Gelfenbaum, G.; Jaffe, B.

    2011-01-01

    The infrequent and unpredictable nature of tsunamis precludes the use of field experiments to measure the hydrodynamic and sediment transport processes that occur. Instead, these processes are often approximated from laboratory, numerical, and theoretical studies or inferred from observations of the resultant sediment deposits. Here Delft3D, a three-dimensional numerical model, is used to simulate the inundation and sediment transport of a tsunami similar in magnitude to the 26 December 2004 Indian Ocean tsunami over one measured and three idealized morphologies. The model is first shown to match well the observations taken at Kuala Meurisi, Sumatra, and then used to examine in detail the processes that occur during the tsunami. The model predicts that at a given cross-shore location the onshore flow accelerates rapidly to a maximum as the wavefront passes, and then gradually decelerates before reversing direction and flowing offshore. The onshore flow does not tend to zero everywhere at maximum inundation, but instead flow reversal occurs near the shoreline even as the wavefront continues to inundate landward. While some sediment is eroded by the passing wavefront, the suspension of sandy sediment is dominated by the long-duration, high-velocity backwash that occurs along the beach face and offshore of the shoreline. Some of the sediment suspended during backwash is advected shoreward by the subsequent wave, creating large spatial gradients in the suspended sediment concentrations, which may not be in equilibrium with the local hydrodynamics. The inundation and transport of sediment during a tsunami can be affected by complexities in the morphological profile and interactions between multiple waves, and many of the hydrodynamic and sediment transport processes predicted here are similar to analogous processes previously observed in the swash zone. Copyright 2011 by the American Geophysical Union.

  18. Innovative approach to collaboration in joint organization of transport processes

    Directory of Open Access Journals (Sweden)

    Marcin Hajdul

    2014-03-01

    Full Text Available Background: The paper presents an innovative approach to the collaboration in joint transport processes within existing supply chains which has been implementing by member companies of ECR Poland. Current approach results in inefficient use of resources due to mainly horizontal cooperation between individual service users and service providers. This effect has been demonstrated by research conducted by the author as well as by the European Environmental Agency. Methods: The aim of this paper is to present how design thinking approach allows creation of new transport business model and communication platform. Results: Created solution allowing simultaneous vertical and horizontal co-operation of independent companies involved in the organization of transport processes. The result of such cooperation is the elimination of identified inefficiencies through sustainable use of available resources. Conclusions: The work is summarized by the results of the implementation of presented solutions within the group of companies operating in the FMCG sector in Poland. Companies were able to reduce their transport costs, increase load factor, reduce empty runs as well as reduce congestion on roads where they operate.

  19. General Services Administration Childcare Radon Results in the Federal Radon Action Plan

    Science.gov (United States)

    GSA made a commitment to support the FRAP’s radon risk goal by sampling for radon in its childcare centers. Over the past two years, the sampling has been performed by independent consultants using recommended standard methods and protocols.

  20. Time variation of radon daughters concentration in snowfall.

    Science.gov (United States)

    Nishikawa, T; Aoki, M; Okabe, S

    1984-05-01

    Time variation of radon daughters concentration in snowfall was measured continuously. The relations of radon daughters concentration in snowfall to the precipitation and to atmospheric radon daughters concentration were investigated. It has become clear that when precipitation is small, radon daughters concentration in snowfall is distributed in a wide range, and that the quantity of radon daughters brought to ground surface by snowfall is proportional to precipitation. Washout effect of the snowfall on atmospheric radon daughters was also investigated.

  1. 9th Saxonian radon day. 11th meeting on radon safe structural engineering; 9. Saechsischer Radontag. 11. Tagung radonsicheres Bauen

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2015-07-01

    The proceedings of the meeting in radon-safe structural engineering covers contributions on the following issues: implementation of the EU standards, radon protection in underground cavities, radon protection at working places, reports on experiences.

  2. Estimation of the radon production rate in granite rocks and evaluation of the implications for geogenic radon potential maps: A case study in Central Portugal.

    Science.gov (United States)

    Pereira, A; Lamas, R; Miranda, M; Domingos, F; Neves, L; Ferreira, N; Costa, L

    2017-01-01

    The goal of this study was to estimate radon gas production rate in granitic rocks and identify the factors responsible for the observed variability. For this purpose, 180 samples were collected from pre-Hercynian and Hercynian rocks in north and central Portugal and analysed for a) (226)Ra activity, b) radon ((222)Rn) per unit mass activity, and c) radon gas emanation coefficient. On a subset of representative samples from the same rock types were also measured d) apparent porosity and e) apparent density. For each of these variables, the values ranged as follows: a) 15 to 587 Bq kg(-1), b) 2 to 73 Bq kg(-1), c) 0.01 to 0.80, d) 0.3 to 11.4 % and e) 2530 to 2850 kg m(-3). Radon production rate varied between 40 to 1386 Bq m(-3) h(-1). The variability observed was associated with geologically late processes of low and high temperature which led to the alteration of the granitic rock with mobilization of U and increase in radon (222)Rn gas emanation. It is suggested that, when developing geogenic radon potential maps, data on uranium concentration in soils/altered rock should be used, rather than data obtained from unaltered rock. Copyright © 2016 Elsevier Ltd. All rights reserved.

  3. Quantifying solute transport processes: are chemically "conservative" tracers electrically conservative?

    Science.gov (United States)

    Singha, Kamini; Li, Li; Day-Lewis, Frederick D.; Regberg, Aaron B.

    2012-01-01

    The concept of a nonreactive or conservative tracer, commonly invoked in investigations of solute transport, requires additional study in the context of electrical geophysical monitoring. Tracers that are commonly considered conservative may undergo reactive processes, such as ion exchange, thus changing the aqueous composition of the system. As a result, the measured electrical conductivity may reflect not only solute transport but also reactive processes. We have evaluated the impacts of ion exchange reactions, rate-limited mass transfer, and surface conduction on quantifying tracer mass, mean arrival time, and temporal variance in laboratory-scale column experiments. Numerical examples showed that (1) ion exchange can lead to resistivity-estimated tracer mass, velocity, and dispersivity that may be inaccurate; (2) mass transfer leads to an overestimate in the mobile tracer mass and an underestimate in velocity when using electrical methods; and (3) surface conductance does not notably affect estimated moments when high-concentration tracers are used, although this phenomenon may be important at low concentrations or in sediments with high and/or spatially variable cation-exchange capacity. In all cases, colocated groundwater concentration measurements are of high importance for interpreting geophysical data with respect to the controlling transport processes of interest.

  4. Inter-comparison of different direct and indirect methods to determine radon flux from soil

    Energy Technology Data Exchange (ETDEWEB)

    Grossi, C., E-mail: claudia.grossi@upc.ed [Institute of Energy (INTE), Technical University of Catalonia (UPC) (Spain); Vargas, A.; Camacho, A. [Institute of Energy (INTE), Technical University of Catalonia (UPC) (Spain); Lopez-Coto, I.; Bolivar, J.P. [University of Huelva (Spain); Xia Yu; Conen, F. [University of Basel (Switzerland)

    2011-01-15

    The physical and chemical characteristics of radon gas make it a good tracer for use in the application of atmospheric transport models. For this purpose the radon source needs to be known on a global scale and this is difficult to achieve by only direct experimental methods. However, indirect methods can provide radon flux maps on larger scales, but their reliability has to be carefully checked. It is the aim of this work to compare radon flux values obtained by direct and indirect methods in a measurement campaign performed in the summer of 2008. Different systems to directly measure radon flux from the soil surface and to measure the related parameters terrestrial {gamma} dose and {sup 226}Ra activity in soil, for indirect estimation of radon flux, were tested. Four eastern Spanish sites with different geological and soil characteristics were selected: Teruel, Los Pedrones, Quintanar de la Orden and Madrid. The study shows the usefulness of both direct and indirect methods for obtaining radon flux data. Direct radon flux measurements by continuous and integrated monitors showed a coefficient of variation between 10% and 23%. At the same time, indirect methods based on correlations between {sup 222}Rn and terrestrial {gamma} dose rate, or {sup 226}Ra activity in soil, provided results similar to the direct measurements, when these proxies were directly measured at the site. Larger discrepancies were found when proxy values were extracted from existing data bases. The participating members involved in the campaign study were the Institute of Energy Technology (INTE) of the Technical University of Catalonia (UPC), Huelva University (UHU), and Basel University (BASEL).

  5. Radon surveys and monitoring at active volcanoes: an open window on deep hydrothermal systems and their dynamics

    Science.gov (United States)

    Cigolini, Corrado; Laiolo, Marco; Coppola, Diego

    2017-04-01

    The behavior of fluids in hydrothermal systems is critical in volcano monitoring and geothermal prospecting. Analyzing the time series of radon emissions on active volcanoes is strategic for detecting and interpreting precursory signals of changes in volcanic activity, eventually leading to eruptions. Radon is a radioactive gas generated from the decay of U bearing rocks, soils and magmas. Although radon has been regarded as a potential precursor of earthquakes, radon anomalies appear to be better suited to forecast volcanic eruptions since we know where paroxysms may occur and we can follow the evolution of volcanic activity. Radon mapping at active volcanoes is also a reliable tool to assess diffuse and concentrated degassing as well as efficiently detecting earthquake-volcano interactions. Systematic radon monitoring has been shown to be a key factor for evaluating the rise of volcanic and hydrothermal fluids. In fact, the decay properties of radon, the duration of radon anomalies together with sampling rates may be cross-checked with the chemistry of hydrothermal fluids (and their transport properties) to constrain fluids ascent rates and to infer the permeability and porosity of rocks in sectors surrounding the active conduits. We hereby further discuss the data of radon surveys and monitoring at Somma-Vesuvius, Stromboli and La Soufrière (Guadeloupe, Lesser Antilles). The integrated analysis of seismic and geochemical data, including radon emissions, may be successfully used in testing temperature distributions and variations of porosity and permeability in volcanic hydrothermal systems and can be used as a proxy to analyze geothermal reservoirs.

  6. Search for radon sources in buildings--kindergartens.

    Science.gov (United States)

    Vaupotic, J

    2002-01-01

    In ten high radon level kindergartens, radon sources were sought by applying a combination of several radon measuring techniques: etched track detectors to obtain average indoor air radon concentration, continuous devices to record radon concentration and see its diurnal variation, and alpha scintillation cells to determine radon concentration in the air entering a room from cracks, holes and sinks in the floor and from under-floor channels. In three cases, a strong local radon source was identified while, in the others, the bad quality of the basic concrete slab was responsible for the high indoor radon concentration.

  7. The radon: evaluation and risk management; Le radon: evaluation et gestion du risque

    Energy Technology Data Exchange (ETDEWEB)

    Lacoste, A.C. [Direction Generale de la Surete Nucleaire et de la Radioprotection, 75 - Paris (France); Masse, R. [Academie des Technologies, 75 - Paris (France); Aurengo, A. [Hopital Pitie-Salpetriere, Service de Medecine Nucleaire, 75 - Paris (France); Erich Wichmann, H. [Neuberberg Munich Univ. (Germany); Timarche, M.; Laurier, D.; Robe, M.Ch. [Institut de Radioprotection et de Surete Nucleaire (IRSN), 92 - Clamart (France); Baubron, J.C.; Bonijoly, D. [BRGM, 75 - Paris (France); Collignan, B. [Centre Scientifique et Technique du Batiment, (CSTB), 75 - Paris (France); Berrier, H. [Direction Gle de l' Urbanisme de l' Habitat et de la Construction, 75 - Paris (France); Jaouen, J. [Direction Departementale des Affaires Sanitaires et Sociales de la Haute-Vienne (France); Caamano, D. [Direction Departementale des Affaires Sanitaires et Sociales de l' Essonne, 91 (France); Guiot, F. [Direction Departementale des Affaires Sanitaires et Sociales de la Haute-Marne (France); Grall, B. [Direction Departementale des Affaires Sanitaires et Sociales de Bretagne (France); Frutos Vasquez, B.; Olaya Adan, M. [Istituto de Ciencias de la Construction (Italy); Garcia Cadierno, J.P.; Martin Matarranz, J.L.; Serrano Renedo, J.; Suarez Mahou, E. [Consejo de Seguridad Nuclear, Madrid (Spain); Fernandez, J.A. [ENUSA Industrias Avanzadas (Spain); Mjones, L.; Pirard, P. [Institut de veille sanitaire, 94415 - Saint-Maurice (France); Godet, J.L.; Rougy, Ch. [Direction Gle de la Surete Nucleaire et de la Radioprotection, 75 - Paris (France)

    2003-06-15

    The radon exposure constitutes for the French population the first cause of natural irradiation among the different natural sources of irradiation. It is possible to have a significant action on it, either by making draught proof in order to avoid to radon to get inside houses, either by ventilating in order to dispel the radon and improve air quality. (N.C.)

  8. Analytical model of reactive transport processes with spatially variable coefficients.

    Science.gov (United States)

    Simpson, Matthew J; Morrow, Liam C

    2015-05-01

    Analytical solutions of partial differential equation (PDE) models describing reactive transport phenomena in saturated porous media are often used as screening tools to provide insight into contaminant fate and transport processes. While many practical modelling scenarios involve spatially variable coefficients, such as spatially variable flow velocity, v(x), or spatially variable decay rate, k(x), most analytical models deal with constant coefficients. Here we present a framework for constructing exact solutions of PDE models of reactive transport. Our approach is relevant for advection-dominant problems, and is based on a regular perturbation technique. We present a description of the solution technique for a range of one-dimensional scenarios involving constant and variable coefficients, and we show that the solutions compare well with numerical approximations. Our general approach applies to a range of initial conditions and various forms of v(x) and k(x). Instead of simply documenting specific solutions for particular cases, we present a symbolic worksheet, as supplementary material, which enables the solution to be evaluated for different choices of the initial condition, v(x) and k(x). We also discuss how the technique generalizes to apply to models of coupled multispecies reactive transport as well as higher dimensional problems.

  9. A perspective on risks from radon

    Energy Technology Data Exchange (ETDEWEB)

    Higson, D. J., E-mail: higsond@bigpond.net.a [Australasian Radiation Protection Society, PO Box 7108, Upper Ferntree Gully, Victoria 3156 (Australia)

    2010-10-15

    In its Statement on Radon (November 2009), the International Commission on Radiological Protection (ICRP) has reduced the upper reference level for radon gas in dwellings to 300 Bq m{sup -3}. The recommended level for workplaces is 1000 Bq m{sup -3}. A risk coefficient of 8 x 10{sup -10} per Bq h m{sup -3} is recommended without reference to smoking habits. On the basis of these figures: 1) The estimated risk of fatal cancer from exposure to radon at home and at work could be greater than the observed risk of accidental death from travelling by car, which would be surprising if true. 2) The estimated risk of lung cancer from radon could be greater than the observed risk of lung cancer from all causes, which is actually known to be dominated by smoking. The author is not aware of any direct evidence of risks from inhaling radon in Australian dwellings, 99% of which have radon levels below 50 Bq m{sup -3}. Evidence available from other countries shows that: 1) The effects of radon in the incidences of lung cancer are uncertain at levels less then about 50-100 Bq m{sup -3}. 2) The estimation of risks at levels below 200 Bq m{sup -3} depends on extrapolation from risks observed at higher levels. 3) Risks to non-smokers from radon are 25 times less than risks to smokers. Its concluded that the ICRP Statement on Radon and radon policies in the US and UK have the potential to cause unwarranted concern. Some people may be made to feel they need to spend money modifying their homes and workplaces to protect occupants from exposure to radon when there is no compelling reason to show that this is necessary. The vast majority of non-smokers do not need to be protected from radon. (Author)

  10. Radon in water of Shu river valley

    Directory of Open Access Journals (Sweden)

    Yelena Kuyanova

    2012-03-01

    Full Text Available The values of radon and its daughter products in water of Shu River valley have been received, using liquid scintillation spectrometry. The radon concentration naturally increases in investigated water samples downstream the Shu River, reaching the maximum value in the Tashutkolsky basin. The radon and its daughter products in a human body of 15 % are in soft tissues have been calculated by a mathematical modeling method. The annual dose from radon and its daughter products calculated by a mathematical modeling method received by the residents living in Shu river valley is 0,03 mSv/year.

  11. Radon barrier: Method of testing airtightness

    DEFF Research Database (Denmark)

    Rasmussen, Torben Valdbjørn; Buch-Hansen, Thomas Cornelius

    2017-01-01

    The test method NBI 167/02 Radon membrane: Test of airtightness can be used for determining the airtightness of a radon barrier as a system solution. The test determines the air infiltration through the radon barrier for a number of levels of air pressure differences. The airflow through versus...... of the barrier with the low air pressure, through a well-defined opening, as a modification of the test method in general. Results, obtained using the improved test method, are shown for a number of radon barriers tested....

  12. Monitoring of sediment transport processes using tracer stones

    Science.gov (United States)

    Redtenbacher, Matthias; Harb, Gabriele; Barbas, Teresa; Schneider, Josef

    2014-05-01

    In the last decades the vulnerability of our civilization to geomorphological damaging events like debris flows and exceptional floods increased. The reasons are, on one side, that the global hydrological cycle became more intense during the recent past and on the other side that the material assets of the population increased. Risk prevention, risk analysis and forecast methods thus became more important. Geomorphological processes are often not easy to analyse. To get information about the probability and the consequences of these increasing events, it is necessary to analyse the availability of sediments in the catchment area, the erosion processes of the sediment and the transport of the sediments along torrents. The project ClimCatch, which started in April 2012, investigates the torrential sediment transport processes in a non-glaciated Alpine valley in Austria and the related natural hazards under the viewpoint of the on-going climate change. Due to an extreme precipitation event in 2011 debris flow-similar discharges occurred in this catchment and since that the sediment sources are highly erodible there. The aims of the project are to derive a quantitative sediment budget model, including geomorphic process domains, determining sediment transport in the river system and the measurement of bed load output, besides others. To quantify river sediment dynamics several different methodologies are applied within the project. Discharge and sediment transport measurement as well as hydrological stations are installed in the catchment area. Aggradation and erosion are analysed by means of laser scanning technology in the sediment storage basin which is located at the outlet of the catchment. The observation and measurement of the sediment transport is performed by the application of radio telemetry stones and colour tracer stones. Line pebble counting, automated grain size determination using photographs and sieving on-site is performed to get qualitative sediment

  13. Characterization of Transport and Solidification in the Metal Recycling Processes

    Energy Technology Data Exchange (ETDEWEB)

    M. A. Ebadian; R. C. Xin; Z. F. Dong

    1997-08-06

    The characterization of the transport and solidification of metal in the melting and casting processes is significant for the optimization of the radioactively contaminated metal recycling and refining processes. . In this research project, the transport process in the melting and solidification of metal was numerically predicted, and the microstructure and radionuclide distribution have been characterized by scanning electron microscope/electron diffractive X-ray (SEWEDX) analysis using cesium chloride (CSC1) as the radionuclide surrogate. In the melting and solidification process, a resistance furnace whose heating and cooling rates are program- controlled in the helium atmosphere was used. The characterization procedures included weighing, melting and solidification, weighing after solidification, sample preparation, and SEM/EDX analysis. This analytical methodology can be used to characterize metal recycling and refining products in order to evaluate the performance of the recycling process. The data obtained provide much valuable information that is necessary for the enhancement of radioactive contaminated metal decontamination and recycling technologies. The numerical method for the prediction of the melting and solidification process can be implemented in the control and monitoring system-of the melting and casting process in radioactive contaminated metal recycling. The use of radionuclide surrogates instead of real radionuclides enables the research to be performed without causing harmfid effects on people or the community. This characterization process has been conducted at the Hemispheric Center for Environmental Technology (HCET) at Florida International University since October 1995. Tests have been conducted on aluminum (Al) and copper (Cu) using cesium chloride (CSCI) as a radionuclide surrogate, and information regarding the radionuclide transfer and distribution in melting and solidification process has been obtained. The numerical simulation of

  14. Residential radon and cancer mortality in Galicia, Spain.

    Science.gov (United States)

    López-Abente, Gonzalo; Núñez, Olivier; Fernández-Navarro, Pablo; Barros-Dios, Juan M; Martín-Méndez, Iván; Bel-Lan, Alejandro; Locutura, Juan; Quindós, Luis; Sainz, Carlos; Ruano-Ravina, Alberto

    2018-01-01

    Residential radon exposure is a serious public health concern, and as such appears in the recommendations of European Code Against Cancer. The objective of this study was to assess the association between residential radon levels and mortality due to different types of cancer, using misaligned data analysis techniques. Mortality data (observed cases) for each of the 313 Galician municipalities were drawn from the records of the National Statistics Institute for the study period (1999-2008). Expected cases were computed using Galician mortality rates for 14 types of malignant tumors as reference, with a total of 56,385 deaths due to the tumors analyzed. The effect estimates of indoor radon (3371 sampling points) were adjusted for sociodemographic variables, altitude, and arsenic topsoil levels (1069 sampling points), using spatial/geostatistical models fitted with stochastic partial differential equations and integrated nested Laplace approximations. These models are capable of processing misaligned data. The results showed a statistical association between indoor radon and lung, stomach and brain cancer in women in Galicia. Apart from lung cancer (relative risk (RR)=1.09), in which a twofold increase in radon exposure led to a 9% rise in mortality, the association was particularly relevant in stomach (RR=1.17) and brain cancer (RR=1.28). Further analytical epidemiologic studies are needed to confirm these results, and an assessment should be made of the advisability of implementing interventions targeting such exposure in higher-risk areas. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

  15. Reported Design Processes for Accessibility in Rail Transport

    DEFF Research Database (Denmark)

    Herriott, Richard; Cook, Sharon

    2014-01-01

    Accessibility is a fundamental requirement in public transport (PT) yet there exists little research on design for accessibility or inclusive design (ID) in this area. This paper sets out to discover what methods are used in the rail sector to achieve accessibility goals and to examine how far......). The research found that the role of users in the design process of manufacturers was limited and that compliance with industry standards was the dominant means to achieving accessibility goals. Design consultancies were willing to apply more user-centred design if the client requested it. Where operators were...... in charge of the design process, accessibility was addressed more comprehensively, with mixed results. The work suggests that the more the design process is divided among actors and geographic space, the harder it is to integrate users....

  16. Simulation of business processes of processing and distribution of orders in transportation

    Directory of Open Access Journals (Sweden)

    Ольга Ігорівна Проніна

    2017-06-01

    Full Text Available Analyzing modern passenger transportation in Ukraine, we can conclude that with the increasing number of urban population the necessity to develop passenger traffic, as well as to improve the quality of transport services is increasing too. The paper examines the three existing models of private passenger transportation (taxi: a model with the use of dispatching service, without dispatching service model and a mixed model. An algorithm of getting an order, processing it, and its implementation according to the given model has been considered. Several arrangements schemes that characterize the operation of the system have been shown in the work as well. The interrelation of the client making an order and the driver who receives the order and executes it has been represented, the server being a connecting link between the customer and the driver and regulating the system as a whole. Business process of private passenger transportation without dispatching service was simulated. Basing on the simulation results it was proposed to supplement the model of private transportation by the making advice system, as well as improving the car selection algorithm. Advice system provides the optimum choice of the car, taking into account a lot of factors. And it will also make it possible to use more efficiently the specific additional services provided by the drivers. Due to the optimization of the order handling process it becomes possible to increase the capacity of the drivers thus increasing their profits. Passenger transportation without the use of dispatching service has some weak points and they were identified. Application of the system will improve transport structure in modern conditions, and improve the transportation basing on modern operating system

  17. Engineered Barrier System Degradation, Flow, and Transport Process Model Report

    Energy Technology Data Exchange (ETDEWEB)

    E.L. Hardin

    2000-07-17

    The Engineered Barrier System Degradation, Flow, and Transport Process Model Report (EBS PMR) is one of nine PMRs supporting the Total System Performance Assessment (TSPA) being developed by the Yucca Mountain Project for the Site Recommendation Report (SRR). The EBS PMR summarizes the development and abstraction of models for processes that govern the evolution of conditions within the emplacement drifts of a potential high-level nuclear waste repository at Yucca Mountain, Nye County, Nevada. Details of these individual models are documented in 23 supporting Analysis/Model Reports (AMRs). Nineteen of these AMRs are for process models, and the remaining 4 describe the abstraction of results for application in TSPA. The process models themselves cluster around four major topics: ''Water Distribution and Removal Model, Physical and Chemical Environment Model, Radionuclide Transport Model, and Multiscale Thermohydrologic Model''. One AMR (Engineered Barrier System-Features, Events, and Processes/Degradation Modes Analysis) summarizes the formal screening analysis used to select the Features, Events, and Processes (FEPs) included in TSPA and those excluded from further consideration. Performance of a potential Yucca Mountain high-level radioactive waste repository depends on both the natural barrier system (NBS) and the engineered barrier system (EBS) and on their interactions. Although the waste packages are generally considered as components of the EBS, the EBS as defined in the EBS PMR includes all engineered components outside the waste packages. The principal function of the EBS is to complement the geologic system in limiting the amount of water contacting nuclear waste. A number of alternatives were considered by the Project for different EBS designs that could provide better performance than the design analyzed for the Viability Assessment. The design concept selected was Enhanced Design Alternative II (EDA II).

  18. Advanced Reactors Thermal Energy Transport for Process Industries

    Energy Technology Data Exchange (ETDEWEB)

    P. Sabharwall; S.J. Yoon; M.G. McKellar; C. Stoots; George Griffith

    2014-07-01

    The operation temperature of advanced nuclear reactors is generally higher than commercial light water reactors and thermal energy from advanced nuclear reactor can be used for various purposes such as liquid fuel production, district heating, desalination, hydrogen production, and other process heat applications, etc. Some of the major technology challenges that must be overcome before the advanced reactors could be licensed on the reactor side are qualification of next generation of nuclear fuel, materials that can withstand higher temperature, improvement in power cycle thermal efficiency by going to combined cycles, SCO2 cycles, successful demonstration of advanced compact heat exchangers in the prototypical conditions, and from the process side application the challenge is to transport the thermal energy from the reactor to the process plant with maximum efficiency (i.e., with minimum temperature drop). The main focus of this study is on doing a parametric study of efficient heat transport system, with different coolants (mainly, water, He, and molten salts) to determine maximum possible distance that can be achieved.

  19. Radon as an Anthropogenic Indoor Air Pollutant

    Science.gov (United States)

    Gillmore, Gavin; Crockett, Robin

    2016-04-01

    Radon is generally regarded as a naturally occurring radiological hazard but we report here measurements of significant, hazardous radon concentrations that arise from man-made sources, including granite ornaments/artefacts, uranium glass and glazed objects as well radium dial watches. This presentation concerns an examination and assessment of health risks from radium and uranium found in historical artefacts, many of which were once viewed as everyday items, and the radon that emanates from them. Such objects were very popular in industrialised countries such as the USA, UK and European countries) particularly between and including the two World Wars but are still readily available. A watch collection examined gave rise to a hazardous radon concentration of 13.24 kBq•m-3 approximately 67 times the Domestic Action Level of 200 Bq•m-3.The results for an aircraft altimeter are comparable to those of the watches, indicating radon activity equivalent to several watches, and also indicate an equilibrium concentration in the 16.3 m3 room ca. 33 times the UK domestic Action Level. Results from a granite block indicate a radon emanation of 19.7 Bq•kg-1, but the indicated equilibrium concentration in the 16.3 m3 room is only ca. 1.7% of the UK domestic Action Level. Uranium-glazed crockery and green uranium glass were scoped for radon activity. The former yielded a radon concentration of ca. 44 Bq•m-3 in a small (7 L) sealed container. The latter yielded a lower radon concentration in a larger (125 L) sealed container of ca. 6 Bq•m-3. This is barely above the background radon concentration in the laboratory, which was typically ca. 1-2 Bq•m-3. Individual items then are capable of giving rise to radon concentrations in excess of the UK Domestic Action Level in rooms in houses, particularly if poorly ventilated. We highlight the gap in the remediation protocols, which are focused on preventing radon entering buildings from outside, with regard to internally

  20. 23 CFR 450.320 - Congestion management process in transportation management areas.

    Science.gov (United States)

    2010-04-01

    ... 23 Highways 1 2010-04-01 2010-04-01 false Congestion management process in transportation... Programming § 450.320 Congestion management process in transportation management areas. (a) The transportation planning process in a TMA shall address congestion management through a process that provides for safe and...

  1. Hydrological balance and water transport processes of partially sealed soils

    Science.gov (United States)

    Timm, Anne; Wessolek, Gerd

    2017-04-01

    With increased urbanisation, soil sealing and its drastic effects on hydrological processes have received a lot of attention. Based on safety concerns, there has been a clear focus on urban drainage and prevention of urban floods caused by storm water events. For this reason, any kind of sealing is often seen as impermeable runoff generator that prevents infiltration and evaporation. While many hydrological models, especially storm water models, have been developed, there are only a handful of empirical studies actually measuring the hydrological balance of (partially) sealed surfaces. These challenge the general assumption of negligible infiltration and evaporation and show that these processes take place even for severe sealing such as asphalt. Depending on the material, infiltration from partially sealed surfaces can be equal to that of vegetated ones. Therefore, more detailed knowledge is needed to improve our understanding and models. In Berlin, two partially sealed weighable lysimeters were equipped with multiple temperature and soil moisture sensors in order to study their hydrological balance, as well as water and heat transport processes within the soil profile. This combination of methods affirms previous observations and offers new insights into altered hydrological processes of partially sealed surfaces at a small temporal scale. It could be verified that not all precipitation is transformed into runoff. Even for a relatively high sealing degree of concrete slabs with narrow seams, evaporation and infiltration may exceed runoff. Due to the lack of plant roots, the hydrological balance is mostly governed by precipitation events and evaporation generally occurs directly after rainfall. However, both surfaces allow for upward water transport from the upper underlying soil layers, sometimes resulting in relatively low evaporation rates on days without precipitation. The individual response of the surfaces differs considerably, which illustrates how

  2. Transport Infrastructure in the Process of Cataloguing Brownfields

    Science.gov (United States)

    Kramářová, Zuzana

    2017-10-01

    To begin with, the identification and follow-up revitalisation of brownfields raises a burning issue in territorial planning as well as in construction engineering. This phenomenon occurs not only in the Czech Republic and Europe, but also world-wide experts conduct its careful investigation. These issues may be divided into several areas. First, it is identifying and cataloguing single territorial localities; next, it means a complex process of locality revitalisation. As a matter of fact, legislative framework represents a separate area, which is actually highly specific in individual countries in accordance with the existing law, norms and regulations (it concerns mainly territorial planning and territory segmentation into appropriate administrative units). Legislative base of the Czech Republic was analysed in an article at WMCAUS in 2016. The solution of individual identification and following cataloguing of brownfields is worked out by Form of Regional Studies within the Legislation of the Czech Republic. Due to huge the scale of issues to be tackled, their content is only loosely defined in regard to Building Act and its implementing regulations, e.g. examining the layout of future construction in the area, locating architecturally or otherwise interesting objects, transport or technical infrastructure management, tourism, socially excluded localities etc. Legislative base does not exist, there is no common method for identifying and cataloguing brownfields. Therefore, individual catalogue lists are subject to customer’s requirements. All the same, the relevant information which the database contains may be always examined. One of them is part about transport infrastructure. The information may be divided into three subareas – information on transport accessibility of the locality, information on the actual infrastructure in the locality and information on the transport accessibility of human resources.

  3. Integrating climate change into the transportation planning process : final report

    Science.gov (United States)

    2008-07-01

    The objective of this study is to advance the practice and application of transportation planning among state, regional, and local transportation planning agencies to successfully meet growing concerns about the relationship between transportation an...

  4. Assessment and management of residential radon health risks: a report from the health Canada radon workshop.

    Science.gov (United States)

    Tracy, Bliss L; Krewski, Daniel; Chen, Jing; Zielinski, Jan M; Brand, Kevin P; Meyerhof, Dorothy

    2006-04-01

    Epidemiologic studies of uranium miners and other underground miners have consistently shown miners exposed to high levels of radon to be at increased risk of lung cancer. More recently, concern has arisen about lung cancer risks among people exposed to lower levels of radon in homes. The current Canadian guideline for residential radon exposure was set in 1988 at 800 Bq/m(3). Because of the accumulation of a considerable body of new scientific evidence on radon lung cancer risks since that time, Health Canada sponsored a workshop to review the current state-of-the-science on radon health risks. The specific objectives of the workshop were (1) to collect and assess scientific information relevant to setting national radon policy in Canada, and (2) to gather information on social, political, and operational considerations in setting national policy. The workshop, held on 3-4 March 2004, was attended by 38 invited scientists, regulators, and other stakeholders from Canada and the United States. The presentations on the first day dealt primarily with scientific issues. The combined analysis of North American residential radon and lung cancer studies was reviewed. The analysis confirmed a small but detectable increase in lung cancer risk at residential exposure levels. Current estimates suggest that radon in homes is responsible for approximately 10% of all lung cancer deaths in Canada, making radon the second leading cause of lung cancer after tobacco smoking. This was followed by a perspective from an UNSCEAR (United Nations Scientific Committee on the Effects of Atomic Radiation) working group on radon. There were two presentations on occupational exposures to radon and two presentations considered the possibility of radon as a causative factor for cardiovascular disease and for cancer in other organs besides the lung. The possible contribution of environmental tobacco smoke to lung cancers in nonsmokers was also considered. Areas for future research were identified

  5. Systematic radon survey over active volcanoes

    Energy Technology Data Exchange (ETDEWEB)

    Seidel, J.L.; Monnin, M.; Garcia Vindas, J.R. [Centre National de la Recherche Cientifique, Montpellier (France). Lab. GBE; Ricard, L.P.; Staudacher, T. [Observatoire Volcanologique Du Pitou de la Fournaise, La Plaine des Cafres (France)

    1999-08-01

    Data obtained since 1993 on Costa Rica volcanos are presented and radon anomalies recorded before the eruption of the Irazu volcano (December 8, 1994) are discussed. The Piton de la Fournaise volcano is inactive since mid 1992. The influence of the external parameters on the radon behaviour is studied and the type of perturbations induced on short-term measurements are individuate.

  6. Removal of Radon from Household Water.

    Science.gov (United States)

    Environmental Protection Agency, Washington, DC. Office of Research and Development.

    By far, the greatest risk to health from radon occurs when the gas enters the house from underlying soil and is inhaled. The U.S. Environmental Protection Agency (EPA) is studying ways to reduce radon in houses, including methods to remove the gas from water to prevent its release in houses when the water is used. While this research has not…

  7. Radon Measurements in Schools: An Interim Report.

    Science.gov (United States)

    Environmental Protection Agency, Washington, DC. Office of Radiation Programs.

    Radon-222 is a colorless, odorless, tasteless, radioactive gas that occurs naturally in soil, rocks, underground water, and air. The United States Environmental Protection Agency (EPA) and other scientific organizations have identified an increased risk of lung cancer associated with exposure to elevated levels of radon in homes. Schools in many…

  8. Radon Measurement in Schools. Revised Edition.

    Science.gov (United States)

    Environmental Protection Agency, Washington, DC.

    The Environmental Protection Agency (EPA) and other major national and international scientific organizations have concluded that radon is a human carcinogen and a serious environmental health problem. The EPA has conducted extensive research on the presence and measurement of radon in schools. This report provides school administrators and…

  9. Radon Reduction Methods: A Homeowner's Guide.

    Science.gov (United States)

    Environmental Protection Agency, Washington, DC.

    The U.S. Environmental Protection Agency (EPA) is studying the effectiveness of various ways to reduce high concentrations of radon in houses. This booklet was produced to share what has been learned with those whose radon problems demand immediate action. The booklet describes nine methods that have been tested successfully--by EPA and/or other…

  10. Features, Events and Processes in UZ Flow and Transport

    Energy Technology Data Exchange (ETDEWEB)

    P. Persoff

    2005-08-04

    The purpose of this report is to evaluate and document the inclusion or exclusion of the unsaturated zone (UZ) features, events, and processes (FEPs) with respect to modeling that supports the total system performance assessment (TSPA) for license application (LA) for a nuclear waste repository at Yucca Mountain, Nevada. A screening decision, either Included or Excluded, is given for each FEP, along with the technical basis for the screening decision. This information is required by the U.S. Nuclear Regulatory Commission (NRC) in 10 CFR 63.114 (d, e, and f) [DIRS 173273]. The FEPs deal with UZ flow and radionuclide transport, including climate, surface water infiltration, percolation, drift seepage, and thermally coupled processes. This analysis summarizes the implementation of each FEP in TSPA-LA (that is, how the FEP is included) and also provides the technical basis for exclusion from TSPA-LA (that is, why the FEP is excluded). This report supports TSPA-LA.

  11. Analysis of reaction and transport processes in zinc air batteries

    CERN Document Server

    Schröder, Daniel

    2016-01-01

    This book contains a novel combination of experimental and model-based investigations, elucidating the complex processes inside zinc air batteries. The work presented helps to answer which battery composition and which air-composition should be adjusted to maintain stable and efficient charge/discharge cycling. In detail, electrochemical investigations and X-ray transmission tomography are applied on button cell zinc air batteries and in-house set-ups. Moreover, model-based investigations of the battery anode and the impact of relative humidity, active operation, carbon dioxide and oxygen on zinc air battery operation are presented. The techniques used in this work complement each other well and yield an unprecedented understanding of zinc air batteries. The methods applied are adaptable and can potentially be applied to gain further understanding of other metal air batteries. Contents Introduction on Zinc Air Batteries Characterizing Reaction and Transport Processes Identifying Factors for Long-Term Stable O...

  12. Estimation of Indoor Radon from Concrete Blocks Used In ...

    African Journals Online (AJOL)

    Radon gas is the most important source of natural radiation. Indoor radon concentration is the main path of human exposure to high radon concentration. Radon contribution from concrete block walls of typical Nigerian dwellings has been estimated from gamma ray spectroscopy measurements of radium concentration ...

  13. Find a Radon Test Kit or Measurement and Mitigation Professional

    Science.gov (United States)

    Find a qualified radon service professional to fix or mitigate your home. If you have questions about a radon, you should contact your state radon contact and/or contact one or both of the two privately-run National Radon Proficiency Programs

  14. Prediction of lung cells oncogenic transformation for induced radon progeny alpha particles using sugarscape cellular automata.

    Science.gov (United States)

    Baradaran, Samaneh; Maleknasr, Niaz; Setayeshi, Saeed; Akbari, Mohammad Esmaeil

    2014-01-01

    Alpha particle irradiation from radon progeny is one of the major natural sources of effective dose in the public population. Oncogenic transformation is a biological effectiveness of radon progeny alpha particle hits. The biological effects which has caused by exposure to radon, were the main result of a complex series of physical, chemical, biological and physiological interactions. The cellular and molecular mechanisms for radon-induced carcinogenesis have not been clear yet. Various biological models, including cultured cells and animals, have been found useful for studying the carcinogenesis effects of radon progeny alpha particles. In this paper, sugars cape cellular automata have been presented for computational study of complex biological effect of radon progeny alpha particles in lung bronchial airways. The model has included mechanism of DNA damage, which has been induced alpha particles hits, and then formation of transformation in the lung cells. Biomarkers were an objective measure or evaluation of normal or abnormal biological processes. In the model, the metabolism rate of infected cell has been induced alpha particles traversals, as a biomarker, has been followed to reach oncogenic transformation. The model results have successfully validated in comparison with "in vitro oncogenic transformation data" for C3H 10T1/2 cells. This model has provided an opportunity to study the cellular and molecular changes, at the various stages in radiation carcinogenesis, involving human cells. It has become well known that simulation could be used to investigate complex biomedical systems, in situations where traditional methodologies were difficult or too costly to employ.

  15. Understanding the transport processes in polymer electrolyte membrane fuel cells

    Science.gov (United States)

    Cheah, May Jean

    Polymer electrolyte membrane (PEM) fuel cells are energy conversion devices suitable for automotive, stationary and portable applications. An engineering challenge that is hindering the widespread use of PEM fuel cells is the water management issue, where either a lack of water (resulting in membrane dehydration) or an excess accumulation of liquid water (resulting in fuel cell flooding) critically reduces the PEM fuel cell performance. The water management issue is addressed by this dissertation through the study of three transport processes occurring in PEM fuel cells. Water transport within the membrane is a combination of water diffusion down the water activity gradient and the dragging of water molecules by protons when there is a proton current, in a phenomenon termed electro-osmotic drag, EOD. The impact of water diffusion and EOD on the water flux across the membrane is reduced due to water transport resistance at the vapor/membrane interface. The redistribution of water inside the membrane by EOD causes an overall increase in the membrane resistance that regulates the current and thus EOD, thereby preventing membrane dehydration. Liquid water transport in the PEM fuel cell flow channel was examined at different gas flow regimes. At low gas Reynolds numbers, drops transitioned into slugs that are subsequently pushed out of the flow channel by the gas flow. The slug volume is dependent on the geometric shape, the surface wettability and the orientation (with respect to gravity) of the flow channel. The differential pressure required for slug motion primarily depends on the interfacial forces acting along the contact lines at the front and the back of the slug. At high gas Reynolds number, water is removed as a film or as drops depending on the flow channel surface wettability. The shape of growing drops at low and high Reynolds number can be described by a simple interfacial energy minimization model. Under flooding conditions, the fuel cell local current

  16. Use of GIS technologies to facilitate the transportation project programming process.

    Science.gov (United States)

    2008-05-01

    Transportation project programming in a transportation agency is a process of matching : potential projects with available funds to accomplish the agencys mission and goals of a : given period of time. Result of this process is normally a transpor...

  17. Result of the intercomparison exercise on radon measuring instruments and radon detectors 'bev- radon ring 2005'

    Energy Technology Data Exchange (ETDEWEB)

    Baumgartner, A. [Vienna Univ. of Technology, Atominstitut, Wien (Austria); Maringer, F.J.; Michai, P.; Kreuziger, M. [BEV-Federal Office of Metrology and Surveying, Wien (Austria)

    2006-07-01

    In spring 2005 the Federal Office of Metrology and Surveying (B.E.V.) invited all in Austria working radon measuring institutes to an intercomparison exercise at the radon calibration laboratory in the Arsenal. The aim of this intercomparison was on the one hand an objective inquiry and documentation of the current metrological potential on the section of radon measurement in Austria - both quantitative and qualitative- and on the other hand an initiative for the participating laboratories to optimize and improve their applied calibration-, measurement and analyse technique. Ten contacted Austrian radon laboratories were prepared to participate on the radon intercomparison exercise. The intercomparison exercise was carried out from 14. till 29. June at the radon calibration laboratory in the Arsenal of the B.E.V.. As radon emanation source a five stepped arranged, at the Arsenal built radon source was used. The source ( A.D.O.T.T.O. 1 is filled with a certified Ra- 226-standard solution of the Czech Metrological Institute (C.M.I.), Prag. A simple statistic based model was used for the evaluation and assessment of the results from the participants, which consider the statistic nature of the radioactive decay combined uncertainty. Altogether 183 measuring instruments participated the intercomparison exercise. Two reference measuring instruments, 22 active and 159 passive measuring instruments. The active measuring instruments formed 6 types of instruments and as passive radon detectors were 7 different types used from the participants. The positioning of the radon measuring instruments and detectors in the radon calibration laboratory was executed in regard to statistic points of view. From the active measuring instruments 17 could qualify and from the passive methods six from eight participants were in compliance to the given criteria. Radon measurements, which could have financial and economics relating implications (e.g. architectural redevelopment or

  18. Novel method of measurement of radon exhalation from building materials.

    Science.gov (United States)

    Awhida, A; Ujić, P; Vukanac, I; Đurašević, M; Kandić, A; Čeliković, I; Lončar, B; Kolarž, P

    2016-11-01

    In the era of the energy saving policy (i.e. more air tight doors and windows), the radon exhaled from building materials tends to increase its concentration in indoor air, which increases the importance of the measurement of radon exhalation from building materials. This manuscript presents a novel method of the radon exhalation measurement using only a HPGe detector or any other gamma spectrometer. Comparing it with the already used methods of radon exhalation measurements, this method provides the measurement of the emanation coefficient, the radon diffusion length and the radon exhalation rate, all within the same measurement, which additionally defines material's radon protective properties. Furthermore it does not necessitate additional equipment for radon or radon exhalation measurement, which simplifies measurement technique, and thus potentially facilitates introduction of legal obligation for radon exhalation determination in building materials. Copyright © 2016 Elsevier Ltd. All rights reserved.

  19. Radon and the system of radiological protection.

    Science.gov (United States)

    Lecomte, J F

    2012-01-01

    At its meeting in Porto, Portugal, in November 2009, the Main Commission of the International Commission on Radiological Protection (ICRP) approved the formation of a new Task Group, reporting to Committee 4, to develop guidance on radiological protection against radon exposure. This article describes the Task Group's draft report entitled "Radiological Protection against Radon Exposure" which has been posted on the ICRP website for public consultation between January and June 2012. In this report, the Commission provides updated guidance on radiological protection against radon exposure. The report was developed considering the recently consolidated ICRP general recommendations, the new scientific knowledge about radon risk, and the experience gained by many organisations and countries in the control of radon exposure. The report describes the characteristics of radon exposure, covering sources and transfer mechanisms, nature of the risk, exposure conditions, similarities with other existing exposure situations, and challenges to manage radon exposure. In order to control radon exposure, the Commission recommends an integrated approach that is focused as much as possible on the management of the building or location in which radon exposure occurs, regardless of the purpose of the building and the category of the occupants. This approach is based on the optimisation principle, and a graded approach according to the degree of responsibilities at stake, notably in workplaces, and the level of ambition of the national authorities. The report emphasises the importance of preventive actions, and provides recommendations on how to control radon exposure in workplaces when workers' exposure can reasonably be regarded as being the responsibility of the operating management. In such a case, workers' exposures are considered to be occupational, and are controlled using the corresponding requirements on the basis of the optimisation principle, and application, as appropriate

  20. Diffusion of radon through concrete block walls: A significant source of indoor radon

    Science.gov (United States)

    Lively, R.S.; Goldberg, L.F.

    1999-01-01

    Basement modules located in southern Minnesota have been the site of continuous radon and environmental measurements during heating seasons since 1993. Concentrations of radon within the basement modules ranged from 70 Bq.m-3 to over 4000 Bq.m-3 between November to April during the three measurement periods. In the soil gas for the same times, concentrations of radon ranged between 25,000 and 70,000 Bq.m-3. Levels of radon within the basement modules changed by factors of five or more within 24 h, in concert with pressure gradients of 4 to 20 Pa that developed between the basement modules and their surroundings. Diffusion is identified as the principal method by which radon is transferred into and out of the basement modules, and appears to be relatively independent of insulating materials and vapour retarders. The variability of radon and correlations with differential pressure gradients may be related to air currents in the block walls and soil that interrupt radon diffusing inward. This yields a net decrease of radon in the basement modules by decay and outward diffusion. Levels of radon within the basement modules increase when the pressure differential is zero and air flow ceases, allowing diffusion gradients to be re-established. Radon levels in both the soil and the basement modules then increase until an equilibrium is achieved.

  1. Process Modeling of Flow, Transport, and Biodegradation in Landfill Bioreactors

    Science.gov (United States)

    Oldenburg, C. M.; Borglin, S. E.; Hazen, T. C.

    2001-12-01

    The need to control gas and leachate production and minimize refuse volume has motivated laboratory experiments and model development for design and assessment of bioremediation treatment processes. In parallel with landfill bioreactor laboratory experiments, we have developed T2LBM, a module for the TOUGH2 multiphase flow and transport simulator that implements a Landfill Bioreactor Model. T2LBM provides simulation capability for the processes of aerobic or anaerobic biodegradation of municipal solid waste and the associated three-dimensional flow and transport of gas, liquid, and heat through the refuse mass. T2LBM considers the components water, acetic acid, carbon dioxide, methane, oxygen, and nitrogen in aqueous and gas phases, with partitioning specified by temperature-dependent Henry's coefficients. T2LBM incorporates a Monod kinetic rate law for the exothermic biodegradation of acetic acid in the aqueous phase by either aerobic or anaerobic microbes as controlled by the local oxygen concentration. Methane and carbon dioxide generation due to biodegradation with corresponding thermal effects are modeled. Acetic acid is considered a proxy for all biodegradable substrates in the refuse. Aerobic and anaerobic microbes are assumed to be immobile and not limited by nutrients in their growth. Although a simplification of complex landfill processes, T2LBM shows reasonable agreement to published laboratory experiments of biodegradation and gas production depending on the choice of numerous input parameters. Simulations of the landfill bioreactor laboratory experiments show that the mechanistic approach of T2LBM can be used to model bioremediation assessment indicators such as oxygen consumption associated with respiration tests. This work was supported by Laboratory Directed Research and Development Funds at Lawrence Berkeley National Laboratory under Department of Energy Contract No. DE-AC03-76SF00098.

  2. Moisture origin and transport processes in Colombia, northern South America

    Science.gov (United States)

    Hoyos, I.; Dominguez, F.; Cañón-Barriga, J.; Martínez, J. A.; Nieto, R.; Gimeno, L.; Dirmeyer, P. A.

    2017-04-01

    We assess the spatial structure of moisture flux divergence, regional moisture sources and transport processes over Colombia, in northern South America. Using three independent methods the dynamic recycling model (DRM), FLEXPART and the Quasi-isentropic back-trajectory (QIBT) models we quantify the moisture sources that contribute to precipitation over the region. We find that moisture from the Atlantic Ocean and terrestrial recycling are the most important sources of moisture for Colombia, highlighting the importance of the Orinoco and Amazon basins as regional providers of atmospheric moisture. The results show the influence of long-range cross-equatorial flow from the Atlantic Ocean into the target region and the role of the study area as a passage of moisture into South America. We also describe the seasonal moisture transport mechanisms of the well-known low-level westerly and Caribbean jets that originate in the Pacific Ocean and Caribbean Sea, respectively. We find that these dynamical systems play an important role in the convergence of moisture over western Colombia.

  3. Features, Events, and Processes in SZ Flow and Transport

    Energy Technology Data Exchange (ETDEWEB)

    K. Economy

    2004-11-16

    This analysis report evaluates and documents the inclusion or exclusion of the saturated zone (SZ) features, events, and processes (FEPs) with respect to modeling used to support the total system performance assessment (TSPA) for license application (LA) of a nuclear waste repository at Yucca Mountain, Nevada. A screening decision, either ''Included'' or ''Excluded'', is given for each FEP along with the technical basis for the decision. This information is required by the U.S. Nuclear Regulatory Commission (NRC) at 10 CFR 63.114 (d), (e), (f) (DIRS 156605). This scientific report focuses on FEP analysis of flow and transport issues relevant to the SZ (e.g., fracture flow in volcanic units, anisotropy, radionuclide transport on colloids, etc.) to be considered in the TSPA model for the LA. For included FEPs, this analysis summarizes the implementation of the FEP in TSPA-LA (i.e., how the FEP is included). For excluded FEPs, this analysis provides the technical basis for exclusion from TSPA-LA (i.e., why the FEP is excluded).

  4. Features, Events, and Processes in SZ Flow and Transport

    Energy Technology Data Exchange (ETDEWEB)

    S. Kuzio

    2005-08-20

    This analysis report evaluates and documents the inclusion or exclusion of the saturated zone (SZ) features, events, and processes (FEPs) with respect to modeling used to support the total system performance assessment (TSPA) for license application (LA) of a nuclear waste repository at Yucca Mountain, Nevada. A screening decision, either Included or Excluded, is given for each FEP along with the technical basis for the decision. This information is required by the U.S. Nuclear Regulatory Commission (NRC) at 10 CFR 63.11(d), (e), (f) [DIRS 173273]. This scientific report focuses on FEP analysis of flow and transport issues relevant to the SZ (e.g., fracture flow in volcanic units, anisotropy, radionuclide transport on colloids, etc.) to be considered in the TSPA model for the LA. For included FEPs, this analysis summarizes the implementation of the FEP in TSPA-LA (i.e., how the FEP is included). For excluded FEPs, this analysis provides the technical basis for exclusion from TSPA-LA (i.e., why the FEP is excluded).

  5. Radon studies for extending Los Azufres geothermal energy field in Mexico

    CERN Document Server

    Tavera, L; Camacho, M E; Chavez, A; Pérez, H; Gómez, J

    1999-01-01

    Los Azufres is a 98 MW producing geothermal energy field situated in the Mexican volcanic belt at the west part of the country. Recently, hydrothermal activity and geochemical analysis of geothermal fluids from the north part of the geothermal field gave indications of a possible geothermal-production area, similar to the already producing field. In order to investigate the activity of geological structures, which are considered the means of geothermal fluids transporters, radon mapping was carried out using sets of 240 LR-115 detectors in the area of interest. Radon values higher than 10 kBq m sup - sup 3 were considered anomalous and indicative of geothermal anomalies.

  6. Radon in the soil air of Estonia.

    Science.gov (United States)

    Petersell, Valter; Täht-Kok, Krista; Karimov, Mark; Milvek, Heli; Nirgi, Siim; Raha, Margus; Saarik, Krista

    2017-01-01

    Several investigations in Estonia during 1996¬-1999 have shown that permissible level (200 Bq/m3) of radon (222Rn) in indoor air is exceeded in 33% of the inspected dwellings. This makes Estonia one of the five countries with highest radon risk in Europe (Fig 1). Due to correlation between the soil radon risk level and radon concentration in houses, small scale radon risk mapping of soil air was carried out (one study point per 70-100 km2). It turned out that one-third of Estonian mainland has high radon risk potential, where radon concentration in soil air exceeds safe limit of 50 kBq/m3. In order to estimate radon content in soil air, two different methods developed in Sweden were used simultaneously. Besides measuring radon content from soil air at the depth of 80 cm with an emanometer (RnM), maximum potential content of radon in soil (RnG) was estimated based on the rate of eU (226Ra) concentration in soil, which was acquired by using gamma-ray spectrometer. Mapping and following studies revealed that simultaneously measured RnG and RnM in study points may often differ. To inspect the cause, several monitoring points were set up in places with different geological conditions. It appeared that unlike the RnG content, which remains close to average level in repeated measurements, the RnM content may differ more than three times periodically. After continuous observations it turned out that concentration of directly measured radon depended on various factors being mostly controlled by mineral composition of soil, properties of topsoil as well as different factors influencing aeration of soil. The results of Rn monitoring show that reliable level of radon risk in Estonian soils can only be acquired by using calculated Rn-concentration in soil air based on eU content and directly measured radon content of soil air in combination with interpreting specific geological and geochemical situations in the study points. Copyright © 2016 Elsevier Ltd. All rights

  7. Roles of transport and mixing processes in kelp forest ecology.

    Science.gov (United States)

    Gaylord, Brian; Nickols, Kerry J; Jurgens, Laura

    2012-03-15

    Fluid-dynamic transport and mixing processes affect birth, death, immigration and emigration rates in kelp forests, and can modulate broader community interactions. In the most highly studied canopy-forming kelp, Macrocystis pyrifera (the giant kelp), models of hydrodynamic and oceanographic phenomena influencing spore movement provide bounds on reproduction, quantify patterns of local and regional propagule supply, identify scales of population connectivity, and establish context for agents of early life mortality. Other analyses yield insight into flow-mediated species interactions within kelp forests. In each case, advances emerge from the use of ecomechanical approaches that propagate physical-biological connections at the scale of the individual to higher levels of ecological organization. In systems where physical factors strongly influence population, community or ecosystem properties, such mechanics-based methods promote crucial progress but are just beginning to realize their full potential.

  8. Engineering charge transport by heterostructuring solution-processed semiconductors

    Science.gov (United States)

    Voznyy, Oleksandr; Sutherland, Brandon R.; Ip, Alexander H.; Zhitomirsky, David; Sargent, Edward H.

    2017-06-01

    Solution-processed semiconductor devices are increasingly exploiting heterostructuring — an approach in which two or more materials with different energy landscapes are integrated into a composite system. Heterostructured materials offer an additional degree of freedom to control charge transport and recombination for more efficient optoelectronic devices. By exploiting energetic asymmetry, rationally engineered heterostructured materials can overcome weaknesses, augment strengths and introduce emergent physical phenomena that are otherwise inaccessible to single-material systems. These systems see benefit and application in two distinct branches of charge-carrier manipulation. First, they influence the balance between excitons and free charges to enhance electron extraction in solar cells and photodetectors. Second, they promote radiative recombination by spatially confining electrons and holes, which increases the quantum efficiency of light-emitting diodes. In this Review, we discuss advances in the design and composition of heterostructured materials, consider their implementation in semiconductor devices and examine unexplored paths for future advancement in the field.

  9. A Cloud Computing Model for Optimization of Transport Logistics Process

    Directory of Open Access Journals (Sweden)

    Benotmane Zineb

    2017-09-01

    Full Text Available In any increasing competitive environment and even in companies; we must adopt a good logistic chain management policy which is the main objective to increase the overall gain by maximizing profits and minimizing costs, including manufacturing costs such as: transaction, transport, storage, etc. In this paper, we propose a cloud platform of this chain logistic for decision support; in fact, this decision must be made to adopt new strategy for cost optimization, besides, the decision-maker must have knowledge on the consequences of this new strategy. Our proposed cloud computing platform has a multilayer structure; this later is contained from a set of web services to provide a link between applications using different technologies; to enable sending; and receiving data through protocols, which should be understandable by everyone. The chain logistic is a process-oriented business; it’s used to evaluate logistics process costs, to propose optimal solutions and to evaluate these solutions before their application. As a scenario, we have formulated the problem for the delivery process, and we have proposed a modified Bin-packing algorithm to improve vehicles loading.

  10. Extended application of radon as a natural tracer in oil reservoirs

    Directory of Open Access Journals (Sweden)

    Moreira R.M.

    2013-05-01

    Full Text Available In the 80's it was a common practice in the study of contamination by NAPL to incorporate a tracer to the medium to be studied. At that time the first applications focused on the use of 222Rn, a naturally occurring radioactive isotope as a natural tracer, appropriate for thermodynamics studies, geology and transport properties in thermal reservoirs. In 1993 the deficit of radon was used to spot and quantify the contamination by DNAPL under the surface. For the first time these studies showed that radon could be used as a partitioning tracer. A methodology that provides alternatives to quantify the oil volume stored in the porous space of oil reservoirs is under development at CDTN. The methodology here applied, widens up and adapts the knowledge acquired from the use of radon as a tracer to the studies aimed at assessing SOR. It is a postulation of this work that once the radon partition coefficient between oil and water is known, SOR will be determined considering the increased amount of radon in the water phase as compared to the amount initially existent as the reservoir is flooded with water. This paper will present a description of the apparatus used and some preliminary results of the experiments.

  11. Study on the influence of CR-39 detector size on radon progeny detection in indoor environments

    Energy Technology Data Exchange (ETDEWEB)

    Pereira, L. A.; Hadler, J. C.; Lixandrão F, A. L.; Guedes, S.; Takizawa, R. H. [Instituto de Física Gleb Wataghin, Universidade Estadual de Campinas, UNICAMP, 13083-970 Campinas, SP (Brazil)

    2014-11-11

    It is well known that radon daughters up to {sup 214}Po are the real contaminants to be considered in case of indoor radon contamination. Assemblies consisting of 6 circular bare sheets of CR-39, a nuclear track detector, with radius varying from 0.15 to 1.2 cm were exposed far from any material surface for periods of approximately 6 months in 13 different indoor rooms (7 workplaces and 6 dwellings), where ventilation was moderate or poor. It was observed that track density was as greater as smaller was the detector radius. Track density data were fitted using an equation deduced based on the assumption that the behavior of radon and its progeny in the air was described by Fick's Law, i.e., when the main mechanism of transport of radon progeny in the air is diffusion. As many people spend great part of their time in closed or poorly ventilated environments, the confirmation they present equilibrium between radon and its progeny is an interesting start for dosimetric calculations concerning this contamination.

  12. Radon, Smoking, and Lung Cancer: The Need to Refocus Radon Control Policy

    Science.gov (United States)

    Mendez, David; Philbert, Martin A.

    2013-01-01

    Exposure to radon is the second leading cause of lung cancer, and the risk is significantly higher for smokers than for nonsmokers. More than 85% of radon-induced lung cancer deaths are among smokers. The most powerful approach for reducing the public health burden of radon is shaped by 2 overarching principles: public communication efforts that promote residential radon testing and remediation will be the most cost effective if they are primarily directed at current and former smokers; and focusing on smoking prevention and cessation is the optimal strategy for reducing radon-induced lung cancer in terms of both public health gains and economic efficiency. Tobacco control policy is the most promising route to the public health goals of radon control policy. PMID:23327258

  13. Radon, smoking, and lung cancer: the need to refocus radon control policy.

    Science.gov (United States)

    Lantz, Paula M; Mendez, David; Philbert, Martin A

    2013-03-01

    Exposure to radon is the second leading cause of lung cancer, and the risk is significantly higher for smokers than for nonsmokers. More than 85% of radon-induced lung cancer deaths are among smokers. The most powerful approach for reducing the public health burden of radon is shaped by 2 overarching principles: public communication efforts that promote residential radon testing and remediation will be the most cost effective if they are primarily directed at current and former smokers; and focusing on smoking prevention and cessation is the optimal strategy for reducing radon-induced lung cancer in terms of both public health gains and economic efficiency. Tobacco control policy is the most promising route to the public health goals of radon control policy.

  14. Measurements of radon and chemical elements: Popocatepetl volcano; Mediciones de radon y elementos quimicos: Volcan Popocatepetl

    Energy Technology Data Exchange (ETDEWEB)

    Pena, P.; Segovia, N.; Lopez, B.; Reyes, A.V. [Instituto Nacional de Investigaciones Nucleares, A.P. 18-1027, 11801 Mexico D.F. (Mexico); Armienta, M.A.; Valdes, C.; Mena, M. [IGFUNAM, Ciudad Universitaria, 04510 Mexico D.F. (Mexico); Seidel, J.L.; Monnin, M. [UMR 5569 CNRS Hydrosciences, Montpellier (France)

    2002-07-01

    The Popocatepetl volcano is a higher risk volcano located at 60 Km from Mexico City. Radon measurements on soil in two fixed seasons located in the north slope of volcano were carried out. Moreover the radon content, major chemical elements and tracks in water samples of three springs was studied. The radon of soil was determined with solid detectors of nuclear tracks (DSTN). The radon in subterranean water was evaluated through the liquid scintillation method and it was corroborated with an Alpha Guard equipment. The major chemical elements were determined with conventional chemical methods and the track elements were measured using an Icp-Ms equipment. The radon on soil levels were lower, indicating a moderate diffusion of the gas across the slope of the volcano. The radon in subterranean water shown few changes in relation with the active scene of the volcano. The major chemical elements and tracks showed a stable behavior during the sampling period. (Author)

  15. Uncertainties about health effects of radon

    Energy Technology Data Exchange (ETDEWEB)

    Abelson, P.H.

    1990-10-19

    The validity of the studies and the interpretation of these studies that are the basis of the Environmental Protection Agency (EPA)'s recommended action level of 4 pCi/liter of radon in residences are strongly questioned. The many assumptions that were made to arrive at this figure and the large amount of money necessary to attain this level in some residences are highlighted. The synergistic effect of smoking and radon exposure on human health is noted. One epidemiological study carried out by Bernard L. Cohn at the University of Pittsburgh has stored relevant data for about a third of the counties of the US, and multivariant analysis of the data led to the conclusion that at low doses of radon found in the average home, radon does not have an adverse effect on health. The author suggests that EPA should give priority to identifying rare circumstances, high permeability and radon content, where high levels of radon prevail and encourage remediation there rather than wholesale action where levels of radon are low.

  16. A study on the correlation between soil radon potential and average indoor radon potential in Canadian cities.

    Science.gov (United States)

    Chen, Jing; Ford, Ken L

    2017-01-01

    Exposure to indoor radon is identified as the main source of natural radiation exposure to the population. Since radon in homes originates mainly from soil gas radon, it is of public interest to study the correlation between radon in soil and radon indoors in different geographic locations. From 2007 to 2010, a total of 1070 sites were surveyed for soil gas radon and soil permeability. Among the sites surveyed, 430 sites were in 14 cities where indoor radon information is available from residential radon and thoron surveys conducted in recent years. It is observed that indoor radon potential (percentage of homes above 200 Bq m(-3); range from 1.5% to 42%) correlates reasonably well with soil radon potential (SRP: an index proportional to soil gas radon concentration and soil permeability; average SRP ranged from 8 to 26). In five cities where in-situ soil permeability was measured at more than 20 sites, a strong correlation (R(2) = 0.68 for linear regression and R(2) = 0.81 for non-linear regression) was observed between indoor radon potential and soil radon potential. This summary report shows that soil gas radon measurement is a practical and useful predictor of indoor radon potential in a geographic area, and may be useful for making decisions around prioritizing activities to manage population exposure and future land-use planning. Crown Copyright © 2016. Published by Elsevier Ltd. All rights reserved.

  17. Residential radon exposure and brain cancer: an ecological study in a radon prone area (Galicia, Spain)

    OpenAIRE

    Ruano-Ravina, Alberto; Aragon?s, Nuria; Kelsey, Karl T.; P?rez-R?os, M?nica; Pi?eiro-Lamas, Mar?a; L?pez-Abente, Gonzalo; Juan M. Barros-Dios

    2017-01-01

    We aimed to know if radon concentration is associated with municipal mortality due to brain cancer in Galicia, Spain. We designed an ecological study taking as study unit Galician municipalities. To be included, municipalities had to have at least three radon measurements. We correlated radon concentrations with municipal mortality due to these malignant tumors during the period 1999?2008. We calculated the relative risk of dying of brain cancers for each municipality and correlated this valu...

  18. Nanomaterial containing wall paints can increase radon concentration in houses located in radon prone areas.

    Science.gov (United States)

    Haghani, M; Mortazavi, S M J; Faghihi, R; Mehdizadeh, S; Moradgholi, J; Darvish, L; Fathi-Pour, E; Ansari, L; Ghanbar-Pour, M R

    2013-09-01

    Nowadays, extensive technological advancements have made it possible to use nanopaints which show exciting properties. In IR Iran excessive radon levels (up to 3700 Bq m-3) have been reported in homes located in radon prone areas. Over the past decades, concerns have been raised about the risk posed by residential radon exposure. This study aims at investigating the effect of using nanomaterial containing wall paints on radon concentration in homes. Two wooden model houses were used in this study. Soil samples from Ramsar high background radiation areas were used for simulating the situation of a typical house in radon-prone areas. Conventional water-soluble wall paint was used for painting the walls of the 1st house model; while the 2nd house model was painted with the same wall paint with montmorillonitenanoclay. Three days after sealing the house models, radon level was measured by using a portable radon survey meter. The mean radon level inside the 1st house model (conventional paint) was 515.3 ± 17.8 Bq/m(3) while the mean radon concentration in the 2nd house model (nano-painted house model) was 570.8 ± 18.5 Bq/m(3). The difference between these means was statistically significant (P<0.001). To the best of our knowledge, this study is the first investigation on the effect of nano-material containing wall paints on indoor radon concentrations.  It can be concluded that nano-material-containing wall paints should not be used in houses with wooden walls located in radon prone areas. Although the mechanism of this effect is not clearly known, decreased porosity in nano-paints might be a key factor in increasing the radon concentration in homes.

  19. Balance letter on information days on radon. The radon in question. To fight against radon; Lettre bilan des journees d'information sur le radon. Le radon en question. Lutter contre le radon

    Energy Technology Data Exchange (ETDEWEB)

    Michelon, Th. [Ministere de la sante et des solidarites, Dir. Generale de la Sante, 75 - Paris (France); Queniart, D. [Institut de Radioprotection et de Surete Nucleaire, 92 - Clamart (France)

    2002-05-15

    Since 1999 actions to detect radon in public building have been implemented, after three years, more than 13 000 establishments have been verified. These actions are going to be reinforced by the publication of a new regulatory frame that will give obligation to householder or operator of a place open to the public to carry out measures of exposure surveillance on geographic areas with a strong exhalation potential of radon. (N.C.)

  20. Comparison of four types of passive and integrated and sensitive radon monitors

    CERN Document Server

    Zhao Gui Zhi

    2002-01-01

    In order to improve the sensitivity of radon measurement method, Fast and Multi-functional Radon Monitor with Electret, Sensitive Miner Radon Monitor, fast and Multifunctional Radon Monitor with High Voltage and PCMR-1 Passive and Continuous Radon Monitor were developed. Except Sensitive Miner Radon Monitor suits for radon concentration measurement only, the others can be used to measure both radon concentration and radon flux rate. Their measurement principles. specifications, quality assurance system, advantages and disadvantages are introduced. The simultaneous measurement results indicate that the errors among them are less than 5% and 10%, respectively, for the average radon concentration measurement and for the average radon flux rate measurement

  1. Effect of impurities on kinetic transport processes in fusion plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Braun, Stefanie

    2010-12-10

    Within the framework of this thesis, different problems arising in connection with impurities have been investigated. Collisional damping of zonal flows in tokamaks: Since the Coulomb collision frequency increases with increasing ion charge, heavy, highly charged impurities play an important role in this process. The effect of such impurities on the linear response of the plasma to an external potential perturbation, as caused by zonal flows, is calculated with analytical methods. In comparison with a pure plasma, the damping of the flows occurs, as expected, considerably faster; for experimentally relevant parameters, the enhancement exceeds the effective charge Z{sub eff} of the plasma. Impurity transport driven by microturbulence in tokamaks: With regard to impurities, it is especially important whether the resulting flows are directed inwards or outwards, since they are deleterious for core energy confinement on the one hand, but on the other hand help protecting plasma-facing components from too high energy fluxes in the edge region. A semi-analytical model is presented describing the resulting impurity fluxes and the stability boundary of the underlying mode. The main goal is to bridge the gap between, on the one hand, costly numerical simulations, which are applicable to a broad range of problems but yield scarcely traceable results, and, on the other hand, analytical theory, which might ease the interpretation of the results but is so far rather rudimentary. The model is based on analytical formulae whenever possible but resorts to a numerical treatment when the approximations necessary for an analytical solution would lead to a substantial distortion of the results. Both the direction of the impurity flux and the stability boundary are found to depend sensitively on the plasma parameters such as the impurity density and the temperature gradient. Pfirsch-Schlueter transport in stellarators: Due to geometry effects, collisional transport plays a much more

  2. Features, Events, and Processes in UZ and Transport

    Energy Technology Data Exchange (ETDEWEB)

    P. Persoff

    2004-11-06

    The purpose of this report is to evaluate and document the inclusion or exclusion of the unsaturated zone (UZ) features, events, and processes (FEPs) with respect to modeling that supports the total system performance assessment (TSPA) for license application (LA) for a nuclear waste repository at Yucca Mountain, Nevada. A screening decision, either ''Included'' or ''Excluded'', is given for each FEP, along with the technical basis for the screening decision. This information is required by the U.S. Nuclear Regulatory Commission (NRC) in 10 CFR 63.114 (d, e, and f) [DIRS 156605]. The FEPs deal with UZ flow and radionuclide transport, including climate, surface water infiltration, percolation, drift seepage, and thermally coupled processes. This analysis summarizes the implementation of each FEP in TSPA-LA (that is, how the FEP is included) and also provides the technical basis for exclusion from TSPA-LA (that is, why the FEP is excluded). This report supports TSPA-LA.

  3. Additional contamination when radon is in excess.

    Science.gov (United States)

    Martín Sánchez, A; de la Torre Pérez, J; Ruano Sánchez, A B; Naranjo Correa, F L

    2013-11-01

    A study of the behavior of the (222)Rn progeny on clothes, skin and hair has been performed in a place with very high radon concentration. In the past, radon concentration was established to be about 32 kBq/m(3) in a very high humidity environment inside a tourist cave in Extremadura (Spain). The results show that (222)Rn daughters are adhered on clothes, skin and hair, adding some radioactive concentration to that due to radon and its progeny existing in the breathable air. Copyright © 2013 Elsevier Ltd. All rights reserved.

  4. Radon - kilder og måling

    DEFF Research Database (Denmark)

    Rasmussen, Torben Valdbjørn; Wraber, Ida Kristina

    Når man skal vurdere en bygnings indeklima er det vigtigt at have viden om radonindholdet. Denne viden får man ved måling, da radon hverken kan ses, lugtes, høres, smages eller føles. Denne anvisning redegør for radons oprindelse og indvirkning på menneskers sundhed. Anvisningen beskriver metoder...... til måling og analyse af radonindholdet i en bygnings indeluft. Læseren får indsigt i, hvordan man relativt let med standardiserede metoder kan eftervise, om en bygning opfylder bygningsreglementets krav til radon i indeluften. Anvisningen henvender sig til bygningsejere, bygherrer, projekterende og...

  5. Soil radon levels across the Amer fault

    Energy Technology Data Exchange (ETDEWEB)

    Font, Ll. [Grup de Fisica de les Radiacions, Edifici Cc, Departament de Fisica, Universitat Autonoma de Barcelona, E-08193 Bellaterra (Spain)], E-mail: lluis.font@uab.cat; Baixeras, C.; Moreno, V. [Grup de Fisica de les Radiacions, Edifici Cc, Departament de Fisica, Universitat Autonoma de Barcelona, E-08193 Bellaterra (Spain); Bach, J. [Unitat de Geodinamica externa, Departament de Geologia, Edifici Cs, Universitat Autonoma de Barcelona, E-08193 Bellaterra (Spain)

    2008-08-15

    Soil radon levels have been measured across the Amer fault, which is located near the volcanic region of La Garrotxa, Spain. Both passive (LR-115, time-integrating) and active (Clipperton II, time-resolved) detectors have been used in a survey in which 27 measurement points were selected in five lines perpendicular to the Amer fault in the village area of Amer. The averaged results show an influence of the distance to the fault on the mean soil radon values. The dynamic results show a very clear seasonal effect on the soil radon levels. The results obtained support the hypothesis that the fault is still active.

  6. Indoor radon concentration forecasting in South Tyrol.

    Science.gov (United States)

    Verdi, L; Weber, A; Stoppa, G

    2004-01-01

    In this paper a modern statistical technique of multivariate analysis is applied to an indoor radon concentration data base. Several parameters are more or less significant in determining the radon concentration inside a building. The elaboration of the information available on South Tyrol makes it possible both to identify the statistically significant variables and to build up a statistical model that allows us to forecast the radon concentration in dwellings, when the values of the same variables involved are given. The results confirm the complexity of the phenomenon.

  7. Soil gas radon assessment and development of a radon risk map in Bolsena, Central Italy.

    Science.gov (United States)

    Cinelli, G; Tositti, L; Capaccioni, B; Brattich, E; Mostacci, D

    2015-04-01

    Vulsini Volcanic district in Northern Latium (Central Italy) is characterized by high natural radiation background resulting from the high concentrations of uranium, thorium and potassium in the volcanic products. In order to estimate the radon radiation risk, a series of soil gas radon measurements were carried out in Bolsena, the principal urban settlement in this area NE of Rome. Soil gas radon concentration ranges between 7 and 176 kBq/m(3) indicating a large degree of variability in the NORM content and behavior of the parent soil material related in particular to the occurrence of two different lithologies. Soil gas radon mapping confirmed the existence of two different areas: one along the shoreline of the Bolsena lake, characterized by low soil radon level, due to a prevailing alluvial lithology; another close to the Bolsena village with high soil radon level due to the presence of the high radioactive volcanic rocks of the Vulsini volcanic district. Radon risk assessment, based on soil gas radon and permeability data, results in a map where the alluvial area is characterized by a probability to be an area with high Radon Index lower than 20 %, while probabilities higher than 30 % and also above 50 % are found close to the Bolsena village.

  8. Application of the can technique and radon gas analyzer for radon exhalation measurements.

    Science.gov (United States)

    Fazal-ur-Rehman; Al-Jarallah, M I; Musazay, M S; Abu-Jarad, F

    2003-01-01

    A passive "can technique" and an active radon gas analyzer with an emanation container were applied for radon exhalation rate measurements from different construction materials, viz. five marble seven ceramic and 100 granite tiles used in Saudi Arabia. The marble and ceramic tiles did not show detectable radon exhalation using the active radon gas analyzer system. However the granite tiles showed relatively high radon exhalations, indicating a relatively high uranium content. A comparison of the radon exhalation rates measured by the two techniques showed a linear correlation coefficient of 0.57. The radon exhalation rates from the granites varied from 0.02 to 6.58 Bqm(-2)h(-1) with an average of 1.35+/-1.40 Bqm(-2)h(-1). The geometric mean and the geometric standard deviation of the frequency distribution were found to be 0.80 and 3.1, respectively. The track density found on the nuclear track detectors in the can technique exposed to the granites, having high exhalation rates, varied linearly with exposure time with a linear correlation coefficient of 0.99. This experimental finding agrees with the theoretical prediction. The can technique showed sensitivity to low radon exhalation rates from ceramic, marble and some granite over a period of 2 months, which were not detectable by the active radon gas analyzer system. The reproducibility of data with both measuring techniques was found to be within a 7% deviation.

  9. Application of the can technique and radon gas analyzer for radon exhalation measurements

    Energy Technology Data Exchange (ETDEWEB)

    Fazal-ur-Rehman E-mail: fazalr@kfupm.edu.sa; Al-Jarallah, M.I.; Musazay, M.S.; Abu-Jarad, F

    2003-12-01

    A passive 'can technique' and an active radon gas analyzer with an emanation container were applied for radon exhalation rate measurements from different construction materials, viz. five marble seven ceramic and 100 granite tiles used in Saudi Arabia. The marble and ceramic tiles did not show detectable radon exhalation using the active radon gas analyzer system. However the granite tiles showed relatively high radon exhalations, indicating a relatively high uranium content. A comparison of the radon exhalation rates measured by the two techniques showed a linear correlation coefficient of 0.57. The radon exhalation rates from the granites varied from 0.02 to 6.58 Bq m{sup -2} h{sup -1} with an average of 1.35{+-}1.40 Bq m{sup -2} h{sup -1}. The geometric mean and the geometric standard deviation of the frequency distribution were found to be 0.80 and 3.1, respectively. The track density found on the nuclear track detectors in the can technique exposed to the granites, having high exhalation rates, varied linearly with exposure time with a linear correlation coefficient of 0.99. This experimental finding agrees with the theoretical prediction. The can technique showed sensitivity to low radon exhalation rates from ceramic, marble and some granite over a period of 2 months, which were not detectable by the active radon gas analyzer system. The reproducibility of data with both measuring techniques was found to be within a 7% deviation.

  10. Residential radon exposure and brain cancer: an ecological study in a radon prone area (Galicia, Spain).

    Science.gov (United States)

    Ruano-Ravina, Alberto; Aragonés, Nuria; Kelsey, Karl T; Pérez-Ríos, Mónica; Piñeiro-Lamas, María; López-Abente, Gonzalo; Barros-Dios, Juan M

    2017-06-15

    We aimed to know if radon concentration is associated with municipal mortality due to brain cancer in Galicia, Spain. We designed an ecological study taking as study unit Galician municipalities. To be included, municipalities had to have at least three radon measurements. We correlated radon concentrations with municipal mortality due to these malignant tumors during the period 1999-2008. We calculated the relative risk of dying of brain cancers for each municipality and correlated this value with municipal radon concentration using Spearman's Rho. 251 municipalities were included, with close to 3,500 radon measurements and an average of 14 radon measurements at each municipality. We observed a significant correlation between residential radon with brain cancer mortality for males and females and the intensity of the correlation was higher for females. These results were reinforced when the analysis was restricted to municipalities with more than 5 radon measurements: Spearman's Rho 0.286 (p-value < 0.001) and Spearman's Rho 0.509 (p-value < 0.001) for males and females, respectively. These results suggest an association between residential radon and brain cancer mortality. More research using more robust epidemiological designs is needed to confirm these findings.

  11. Particle transport model sensitivity on wave-induced processes

    Science.gov (United States)

    Staneva, Joanna; Ricker, Marcel; Krüger, Oliver; Breivik, Oyvind; Stanev, Emil; Schrum, Corinna

    2017-04-01

    Different effects of wind waves on the hydrodynamics in the North Sea are investigated using a coupled wave (WAM) and circulation (NEMO) model system. The terms accounting for the wave-current interaction are: the Stokes-Coriolis force, the sea-state dependent momentum and energy flux. The role of the different Stokes drift parameterizations is investigated using a particle-drift model. Those particles can be considered as simple representations of either oil fractions, or fish larvae. In the ocean circulation models the momentum flux from the atmosphere, which is related to the wind speed, is passed directly to the ocean and this is controlled by the drag coefficient. However, in the real ocean, the waves play also the role of a reservoir for momentum and energy because different amounts of the momentum flux from the atmosphere is taken up by the waves. In the coupled model system the momentum transferred into the ocean model is estimated as the fraction of the total flux that goes directly to the currents plus the momentum lost from wave dissipation. Additionally, we demonstrate that the wave-induced Stokes-Coriolis force leads to a deflection of the current. During the extreme events the Stokes velocity is comparable in magnitude to the current velocity. The resulting wave-induced drift is crucial for the transport of particles in the upper ocean. The performed sensitivity analyses demonstrate that the model skill depends on the chosen processes. The results are validated using surface drifters, ADCP, HF radar data and other in-situ measurements in different regions of the North Sea with a focus on the coastal areas. The using of a coupled model system reveals that the newly introduced wave effects are important for the drift-model performance, especially during extremes. Those effects cannot be neglected by search and rescue, oil-spill, transport of biological material, or larva drift modelling.

  12. Radiological risk assessment of environmental radon

    Energy Technology Data Exchange (ETDEWEB)

    Khalid, Norafatin; Majid, Amran Ab; Yahaya, Redzuwan; Yasir, Muhammad Samudi [Nuclear Science Programme, School of Applied Physics, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, 43600 Bangi, Selangor Darul Ehsan (Malaysia)

    2013-11-27

    Measurements of radon gas ({sup 222}Rn) in the environmental are important to assess indoor air quality and to study the potential risk to human health. Generally known that exposure to radon is considered the second leading cause of lung cancer after smoking. The environmental radon concentration depends on the {sup 226}Ra concentration, indoor atmosphere, cracking on rocks and building materials. This study was carried out to determine the indoor radon concentration from selected samples of tin tailings (amang) and building materials in an airtight sealed homemade radon chamber. The radiological risk assessment for radon gas was also calculated based on the annual exposure dose, effective dose equivalent, radon exhalation rates and fatal cancer risk. The continuous radon monitor Sun Nuclear model 1029 was used to measure the radon concentration emanates from selected samples for 96 hours. Five types of tin tailings collected from Kampar, Perak and four samples of building materials commonly used in Malaysia dwellings or building constructions were analysed for radon concentration. The indoor radon concentration determined in ilmenite, monazite, struverite, xenotime and zircon samples varies from 219.6 ± 76.8 Bq m{sup −3} to 571.1 ± 251.4 Bq m{sup −3}, 101.0 ± 41.0 Bq m{sup −3} to 245.3 ± 100.2 Bq m{sup −3}, 53.1 ± 7.5 Bq m{sup −3} to 181.8 ± 9.7 Bq m{sup −3}, 256.1 ± 59.3 Bq m{sup −3} to 652.2 ± 222.2 Bq m{sup −3} and 164.5 ± 75.9 Bq m{sup −3} to 653.3 ± 240.0 Bq m{sup −3}, respectively. Whereas, in the building materials, the radon concentration from cement brick, red-clay brick, gravel aggregate and cement showed 396.3 ± 194.3 Bq m{sup −3}, 192.1 ± 75.4 Bq m{sup −3}, 176.1 ± 85.9 Bq m{sup −3} and 28.4 ± 5.7 Bq m{sup −3}, respectively. The radon concentration in tin tailings and building materials were found to be much higher in xenotime and cement brick samples than others. All samples in tin tailings were exceeded the

  13. Application studies of RFID technology in the process of coal logistics transport

    Science.gov (United States)

    Qiao, Bingqin; Chang, Xiaoming; Hao, Meiyan; Kong, Dejin

    2012-04-01

    For quality control problems in coal transport, RFID technology has been proposed to be applied to coal transportation process. The whole process RFID traceability system from coal production to consumption has been designed and coal supply chain logistics tracking system integration platform has been built, to form the coal supply chain traceability and transport tracking system and providing more and more transparent tracking and monitoring of coal quality information for consumers of coal. Currently direct transport and combined transport are the main forms of coal transportation in China. The means of transport are cars, trains and ships. In the booming networking environment of RFID technology, the RFID technology will be applied to coal logistics and provide opportunity for the coal transportation tracking in the process transportation.

  14. The relationship of title VI requirements to Florida's transportation planning process.

    Science.gov (United States)

    2011-10-01

    The Florida Department of Transportation (FDOT) and metropolitan planning organizations (MPO) in Florida are : required to address Title VI and environmental justice (EJ) in the transportation planning process. This study : reviews those practices an...

  15. Regressionanalysis of radon measurements; Regressionsanalysen von Radonmessungen

    Energy Technology Data Exchange (ETDEWEB)

    Buermeyer, J.; Neugebauer, T.; Hingmann, H.; Grimm, V.; Breckow, J. [Technische Hochschule Mittelhessen (THM), Giessen (Germany). Inst. fuer Medizinische Physik und Strahlenschutz (IMPS); Gundlach, M. [Technische Hochschule Mittelhessen (THM), Giessen (Germany). Fachbereich fuer Mathematik, Naturwissenschaften und Informatik

    2016-07-01

    In the course of the renewal of the Radiation Protection Guidelines for Germany, radon becomes a more prominent concern. Thus, it is important to gain more information on the temporal behaviour of radon and its measureable parameters. This work focuses on the determination on possible influencing factors using regression-analysis methods. So far the radon concentration has been analysed and it was revealed, that the most important impact comes from the gradient of the temperature and pressure as the difference of the values in and outside the building. The carbon dioxide, which was logged as an indicator for the influences of the inhabitant does not show the high influence on the Radon levels as expected.

  16. Novel Radon Sub-Slab Suctioning System

    DEFF Research Database (Denmark)

    Rasmussen, Torben Valdbjørn

    2013-01-01

    A new principle for radon protection is currently presented which makes use of a system of horizontal pressurised air ducts located within the lower part of the rigid insulation layer of the ground-floor slab. The function of this system is based on the principles of pressure reduction within...... the zone below the ground-floor construction. For this purpose a new system of prefabricated lightweight elements is introduced. The effectiveness of the system is demonstrated for the case of a ground-floor reinforced concrete slab situated on top of a rigid insulation layer (consisting of a thermal...... a grid of horizontal air ducts with low pressure which are able to remove air and radon from the ground. Results showed the system to be effective in preventing radon infiltrating from the ground through the ground-floor slab, avoiding high concentrations of radon being accumulated inside houses...

  17. Domestic Radon and Childhood Cancer in Denmark

    DEFF Research Database (Denmark)

    Raaschou-Nielsen, Ole; Andersen, Claus Erik; Andersen, Helle P.

    2008-01-01

    Background: Higher incidence rates of childhood cancer and particularly leukemia have been observed in regions with higher radon levels, but case-control studies have given inconsistent results. We tested the hypothesis that domestic radon exposure increases the risk for childhood cancer. Methods......: We identified 2400 incident cases of leukemia, central nervous system tumor, and malignant lymphoma diagnosed in children between 1968 and 1994 in the Danish Cancer Registry. Control children (n = 6697) were selected from the Danish Central Population Registry. Radon levels in residences of children...... and the cumulated exposure of each child were calculated as the product of exposure level and time, for each address occupied during childhood. Results: Cumulative radon exposure was associated with risk for acute lymphoblastic leukemia (ALL), with rate ratios of 1.21 (95% confidence interval = 0...

  18. Distribution of indoor radon levels in Mexico

    CERN Document Server

    Espinosa, G; Rickards, J; Gammage, R B

    1999-01-01

    Our laboratory has carried out a systematic monitoring and evaluation of indoor radon concentration levels in Mexico for ten years. The results of the distribution of indoor radon levels for practically the entire country are presented, together with information on geological characteristics, population density, socioeconomic levels of the population, and architectural styles of housing. The measurements of the radon levels were made using the passive method of nuclear tracks in solids with the end-cup system. CR-39 was used as the detector material in combination with a one-step chemical etching procedure and an automatic digital- image counting system. Wherever a high level was measured, a confirming measurement was made using a dynamic method. The results are important for future health studies, including the eventual establishment of patterns for indoor radon concentration, as it has been done in the USA and Europe.

  19. Comparison of retrospective and contemporary indoor radon measurements in a high-radon area of Serbia

    Energy Technology Data Exchange (ETDEWEB)

    Zunic, Z.S. [Institute of Nuclear Sciences ' Vinca' , Belgrade (Serbia); Yarmoshenko, I.V. [Institute of Industrial Ecology, Ural Branch of Russian Academy of Sciences, Ekaterinburg (Russian Federation)], E-mail: ivy@ecko.uran.ru; Kelleher, K. [Radiological Protection Institute of Ireland, Dublin (Ireland); Paridaens, J. [SCK.CEN Mol (Belgium); Mc Laughlin, J.P. [School of Physics, University College Dublin (Ireland); Celikovic, I.; Ujic, P. [Institute of Nuclear Sciences ' Vinca' , Belgrade (Serbia); Onischenko, A.D. [Institute of Industrial Ecology, Ural Branch of Russian Academy of Sciences, Ekaterinburg (Russian Federation); Jovanovic, S.; Demajo, A. [Institute of Nuclear Sciences ' Vinca' , Belgrade (Serbia); Birovljev, A. [Radonlab Ltd., Oslo (Norway); Bochicchio, F. [Italian National Institute of Health, Rome (Italy)

    2007-11-15

    In Niska Banja, Serbia, which is a high-radon area, a comparison was made between two retrospective radon measuring methods and contemporary radon measurements. The two retrospective methods derive the radon concentrations that occurred in dwellings over longer periods in the past, based on the amount of trapped {sup 210}Po on the surface of glass objects (surface traps, ST) or in the bulk of porous materials (volume traps, VT). Both surface implanted {sup 210}Po in glass objects and contemporary radon in air were measured in 46 rooms, distributed in 32 houses of this radon spa-town, using a dual alpha track detector configuration (CR-39 and LR115) and CR-39 track etched detectors, respectively. In addition to the use of surface trap measurements, in 18 rooms (distributed in 15 houses) VT samples of suitable material were also collected, allowing to compare ST and VT retrospective radon concentration estimates. For each room, contemporary annual radon concentrations (CONT) were measured or estimated using seasonal correction factors. The distribution of the radon concentration in all data sets was found to be close to lognormal (Chi-square test > 0.05). Geometric means (GM) are similar, ranging from 1040 to 1380 Bq m{sup -3}, whereas geometric standard deviations (GSD) for both the retrospective methods are greater than for the CONT method, showing reasonable agreement between VT, ST and CONT measurements. A regression analysis, with respect to the lognormal distribution of each data set, shows that for VT-ST the correlation coefficient r is 0.85, for VT-CONT r is 0.82 and for ST-CONT r is 0.73. Comparison of retrospective and contemporary radon concentrations with regard to supposed long-term indoor radon changes further supports the principal agreement between the retrospective and conventional methods.

  20. SURVEY IN KRASNOKAMENSK CITY ON THE CONTENT OF INDOOR RADON

    Directory of Open Access Journals (Sweden)

    A. M. Marennyi

    2013-01-01

    Full Text Available Survey of dwellings and enterprises of the Krasnokamensk city on the indoor radon content were performed. The radon volume activity measurements were carried out by integral method with the help of track chambers. Chambers were exhibited in the heating and the warm periods of the year for the 3-4 months in the same premises. The values of equivalent equilibrium volume activity of radon and doses from radon were obtained. It is shown, that the situation with the radon irradiation of the population of Krasnokamensk city in general meets the requirements of the radiation safety standards. Seasonal relations of volume radon activity in the premises are presented.

  1. Space Transportation System Liftoff Debris Mitigation Process Overview

    Science.gov (United States)

    Mitchell, Michael; Riley, Christopher

    2011-01-01

    Liftoff debris is a top risk to the Space Shuttle Vehicle. To manage the Liftoff debris risk, the Space Shuttle Program created a team with in the Propulsion Systems Engineering & Integration Office. The Shutt le Liftoff Debris Team harnesses the Systems Engineering process to i dentify, assess, mitigate, and communicate the Liftoff debris risk. T he Liftoff Debris Team leverages off the technical knowledge and expe rtise of engineering groups across multiple NASA centers to integrate total system solutions. These solutions connect the hardware and ana lyses to identify and characterize debris sources and zones contribut ing to the Liftoff debris risk. The solutions incorporate analyses sp anning: the definition and modeling of natural and induced environmen ts; material characterizations; statistical trending analyses, imager y based trajectory analyses; debris transport analyses, and risk asse ssments. The verification and validation of these analyses are bound by conservative assumptions and anchored by testing and flight data. The Liftoff debris risk mitigation is managed through vigilant collab orative work between the Liftoff Debris Team and Launch Pad Operation s personnel and through the management of requirements, interfaces, r isk documentation, configurations, and technical data. Furthermore, o n day of launch, decision analysis is used to apply the wealth of ana lyses to case specific identified risks. This presentation describes how the Liftoff Debris Team applies Systems Engineering in their proce sses to mitigate risk and improve the safety of the Space Shuttle Veh icle.

  2. NATO Advanced Study Institute on Chemical Transport in Melasomatic Processes

    CERN Document Server

    1987-01-01

    As indicated on the title page, this book is an outgrowth of the NATO Advanced Study Institute (ASI) on Chemical Transport in Metasomatic Processes, which was held in Greece, June 3-16, 1985. The ASI consisted of five days of invited lectures, poster sessions, and discussion at the Club Poseidon near Loutraki, Corinthia, followed by a two-day field trip in Corinthia and Attica. The second week of the ASI consisted of an excursion aboard M/S Zeus, M/Y Dimitrios II, and the M/S Irini to four of the Cycladic Islands to visit, study, and sample outstanding exposures of metasomatic activity on Syros, Siphnos, Seriphos, and Naxos. Nine­ teen invited lectures and 10 session chairmen/discussion leaders participated in the ASI, which was attended by a total of 92 professional scientists and graduate stu­ dents from 15 countries. Seventeen of the invited lectures and the Field Excursion Guide are included in this volume, together with 10 papers and six abstracts representing contributed poster sessions. Although more...

  3. RADON AND CARCINOGENIC RISK IN MOSCOW

    Directory of Open Access Journals (Sweden)

    S. M. Golovanev

    2015-01-01

    Full Text Available Objective: comparative evaluation of carcinogenic risk inMoscowfrom radon in indoor and atmospheric pollutants.Materials and methods: the lung cancer incidence in Moscow; radiation-hygienic passport of the territory; .U.S. EPA estimated average age at all and radon induced deaths, years of life lost; Report of UNSCEAR 2006 and WHO handbook on indoor radon, 2009. Trend analysis of incidence; evaluation of the excess relative risk; assessment of ratio radon-induced population risk and published values оf total population carcinogenic risk from chemical carcinogens.Results: it is shown that the 304 cases of lung cancer per year (1. 85 10-3 on average from 2006 to 2011 (21280diseases for 70 years in addition to background level induced by radon; the differences in average trends of all lungcancer incidence in the districts can exceed 25%.Conclusion. The potential of risk reduction by measures of mitigation radon concentration exceeds 5 times the cost efficiency to reduce emissions from vehicles and can reduce cancer incidence, on average 236 cases per year; population risk 16520 cases over 70 years or save not less than 2832 person-years of life per year. The annual effect of reducing losses from not-survival of 12 years as a result of radon-induced lung cancer deaths exceeds 14160000 dollars. The evaluating of the carcinogenic risk from radon in accordance with the definition of population risk increases the predictive evaluation of the effectiveness of preventive measures more than twice.

  4. Radon isotope measurements as a monitoring tool for CO2 leakage in geological storage

    Science.gov (United States)

    Grandia, F.; Mazadiego, L. F.; de Elío, J.; Ortega, M.; Bruno, J.

    2011-12-01

    Early detection of the failure of the seal integrity is fundamental in the monitoring plan of a deep geological CO2 storage. A number of methods of leakage control are based on changes in fluid geochemistry (shallow water, soil gases) providing valuable indicators. Among them, the measurement of CO2 fluxes in the soil-atmosphere interface is commonly used since it can be easily done using portable infra-red analyzers (i.e., accumulation chambers). However, initial emission of CO2 from storage horizon could be masked by fluxes from biological activity, limiting its applicability as an early alarm system. The measurement of fluxes of trace gas (Rn, He, VOC) that are virtually absent in the pre-injection baseline turns out a promising complementary method. The measurement of radon isotopes has been long used for the observation of mass transport from deep reservoirs to surface despite the flux of 222Rn and 220Rn is usually very limited in sedimentary basins due to the short half-life of these isotopes. The enhanced transport of radon in CO2 fluxes has been reported from natural systems, resulting in concentration in air up to several thousands of Bq/m3. In the frame of the Compostilla pilot plant project in Spain, a number of methodologies to measure radon emission are being tested in natural systems to select of the most reliable and cost-effective method to be used in leakage control. These methods are (1) Scintillation detector EDA RD-200, (2) Track Etch °, (3) Ionization Chamber and (4) alpha spectroscopy SARAD RTM 200. Some of them are capable of measuring the isotopes separately (SARAD) whereas others just detect the bulk radon concentration. Also, these methods follow distinct procedures and acquisition times. The studied natural sites are located in central and NE Spain (Campo de Calatrava and La Selva basins), and in central Italy (Arezzo basin). Apparently, radon isotopes (up 200000 Bq/m3) are measured far from parent isotopes, and they are coupled to

  5. Delay functions in trip assignment for transport planning process

    Science.gov (United States)

    Leong, Lee Vien

    2017-10-01

    In transportation planning process, volume-delay and turn-penalty functions are the functions needed in traffic assignment to determine travel time on road network links. Volume-delay function is the delay function describing speed-flow relationship while turn-penalty function is the delay function associated to making a turn at intersection. The volume-delay function used in this study is the revised Bureau of Public Roads (BPR) function with the constant parameters, α and β values of 0.8298 and 3.361 while the turn-penalty functions for signalized intersection were developed based on uniform, random and overflow delay models. Parameters such as green time, cycle time and saturation flow were used in the development of turn-penalty functions. In order to assess the accuracy of the delay functions, road network in areas of Nibong Tebal, Penang and Parit Buntar, Perak was developed and modelled using transportation demand forecasting software. In order to calibrate the models, phase times and traffic volumes at fourteen signalised intersections within the study area were collected during morning and evening peak hours. The prediction of assigned volumes using the revised BPR function and the developed turn-penalty functions show close agreement to actual recorded traffic volume with the lowest percentage of accuracy, 80.08% and the highest, 93.04% for the morning peak model. As for the evening peak model, they were 75.59% and 95.33% respectively for lowest and highest percentage of accuracy. As for the yield left-turn lanes, the lowest percentage of accuracy obtained for the morning and evening peak models were 60.94% and 69.74% respectively while the highest percentage of accuracy obtained for both models were 100%. Therefore, can be concluded that the development and utilisation of delay functions based on local road conditions are important as localised delay functions can produce better estimate of link travel times and hence better planning for future

  6. Quantitative analysis of microtubule transport in growing nerve processes

    DEFF Research Database (Denmark)

    Ma*, Ytao; Shakiryanova*, Dinara; Vardya, Irina

    2004-01-01

    assumed that only a small fraction of MTs translocates along the axon by saltatory movement reminiscent of the fast axonal transport. Such intermittent "stop and go" MT transport has been difficult to detect or to exclude by using direct video microscopy methods. In this study, we measured...

  7. Occupational doses from radon in Spanish spas.

    Science.gov (United States)

    Soto, J; Gómez, J

    1999-04-01

    Recent international recommendations have included exposure to natural radiation as one of the sources to monitor in certain occupationally exposed groups. Among those mentioned are workers in thermal spas, who may be exposed to high radiation doses due to the high concentration of radon in the indoor air of the spa. This paper presents the methodology and the results of an evaluation of radiation doses to the staff in different thermal spas in Spain. Different series of samples were collected and measurements made for the radon concentrations in water in 54 spas and in air in 20 spas. In six of the latter group, the air radon concentration was studied in different working areas occupied by the employees. The radon concentrations in water were between radon concentrations in air were between radon concentration in their main working area. By means of an exposure-dose conversion factor of 1.43 Sv per J h m(-3), the estimated effective doses were found to lie between 1 and 44 mSv y(-1). This upper limit is higher than the recommended annual limit of 20 mSv y(-1) for an occupational dose.

  8. Development of high sensitivity radon detectors

    CERN Document Server

    Takeuchi, Y; Kajita, T; Tasaka, S; Hori, H; Nemoto, M; Okazawa, H

    1999-01-01

    High sensitivity detectors for radon in air and in water have been developed. We use electrostatic collection and a PIN photodiode for these detectors. Calibration systems have been also constructed to obtain collection factors. As a result of the calibration study, the absolute humidity dependence of the radon detector for air is clearly observed in the region less than about 1.6 g/m sup 3. The calibration factors of the radon detector for air are 2.2+-0.2 (counts/day)/(mBq/m sup 3) at 0.08 g/m sup 3 and 0.86+-0.06 (counts/day)/(mBq/m sup 3) at 11 g/m sup 3. The calibration factor of the radon detector for water is 3.6+-0.5 (counts/day)/(mBq/m sup 3). The background level of the radon detector for air is 2.4+-1.3 counts/day. As a result, one standard deviation excess of the signal above the background of the radon detector for air should be possible for 1.4 mBq/m sup 3 in a one-day measurement at 0.08 g/m sup 3.

  9. Radon capture with silver exchanged zeolites

    Energy Technology Data Exchange (ETDEWEB)

    Hedstroem, H. [Chalmers Univ. of Technology, Goeteborg (Sweden). Nuclear Chemistry; Foreman, M.; Ekberg, C. [Chalmers Univ. of Technology, Goeteborg (Sweden). Nuclear Chemistry; Chalmers Univ. of Technology, Goeteborg (Sweden). Industrial Materials Recycling; Ramebaeck, H. [Chalmers Univ. of Technology, Goeteborg (Sweden). Nuclear Chemistry; Chalmers Univ. of Technology, Goeteborg (Sweden). Industrial Materials Recycling; Swedish Defence Research Agency (FOI), Division of CBRN Defence and Security, Umeaa (Sweden)

    2012-07-01

    To enable laboratory work with larger amounts of {sup 226}Ra and its decay products, e.g., {sup 222}Rn and its daughters, these need to be captured in order to avoid unnecessary alpha contamination of the laboratory work space and ventilation systems. In this study, radon gas was pumped through a column filled with the silver exchanged zeolite called 'silver exchanged molecular sieves 13X' (Ag{sub 84}Na{sub 2}[(AlO{sub 2}){sub 86}(SiO{sub 2}){sub 106}].xH{sub 2}O). After exposure to radon, the radioactivity of the zeolite was measured repeatedly using high resolution gamma spectrometry. It was shown that radon was captured and retained in the silver exchanged zeolite. The zeolites' ability to retain radon was decreased by formation of metallic silver, caused by ionizing radiation. However, the zeolite was regenerated by heating and its radon capture ability was restored. The daughters of radon are not in gas phase and will hence stay on the column. (orig.)

  10. Multiple attenuation to reflection seismic data using Radon filter and Wave Equation Multiple Rejection (WEMR) method

    Energy Technology Data Exchange (ETDEWEB)

    Erlangga, Mokhammad Puput [Geophysical Engineering, Institut Teknologi Bandung, Ganesha Street no.10 Basic Science B Buliding fl.2-3 Bandung, 40132, West Java Indonesia puput.erlangga@gmail.com (Indonesia)

    2015-04-16

    Separation between signal and noise, incoherent or coherent, is important in seismic data processing. Although we have processed the seismic data, the coherent noise is still mixing with the primary signal. Multiple reflections are a kind of coherent noise. In this research, we processed seismic data to attenuate multiple reflections in the both synthetic and real seismic data of Mentawai. There are several methods to attenuate multiple reflection, one of them is Radon filter method that discriminates between primary reflection and multiple reflection in the τ-p domain based on move out difference between primary reflection and multiple reflection. However, in case where the move out difference is too small, the Radon filter method is not enough to attenuate the multiple reflections. The Radon filter also produces the artifacts on the gathers data. Except the Radon filter method, we also use the Wave Equation Multiple Elimination (WEMR) method to attenuate the long period multiple reflection. The WEMR method can attenuate the long period multiple reflection based on wave equation inversion. Refer to the inversion of wave equation and the magnitude of the seismic wave amplitude that observed on the free surface, we get the water bottom reflectivity which is used to eliminate the multiple reflections. The WEMR method does not depend on the move out difference to attenuate the long period multiple reflection. Therefore, the WEMR method can be applied to the seismic data which has small move out difference as the Mentawai seismic data. The small move out difference on the Mentawai seismic data is caused by the restrictiveness of far offset, which is only 705 meter. We compared the real free multiple stacking data after processing with Radon filter and WEMR process. The conclusion is the WEMR method can more attenuate the long period multiple reflection than the Radon filter method on the real (Mentawai) seismic data.

  11. Application of a radon model to explain indoor radon levels in a Swedish house

    CERN Document Server

    Font, L; Jönsson, G; Enge, W; Ghose, R

    1999-01-01

    Radon entry from soil into indoor air and its accumulation indoors depends on several parameters, the values of which normally depend on the specific characteristics of the site. The effect of a specific parameter is often difficult to explain from the result of indoor radon measurements only. The adaptation of the RAGENA (RAdon Generation, ENtry and Accumulation indoors) model to a Swedish house to characterise indoor radon levels and the relative importance of the different radon sources and entry mechanisms is presented. The building is a single-zone house with a naturally-ventilated crawl space in one part and a concrete floor in another part, leading to different radon levels in the two parts of the building. The soil under the house is moraine, which is relatively permeable to radon gas. The house is naturally-ventilated. The mean indoor radon concentration values measured with nuclear track detectors in the crawl-space and concrete parts of the house are respectively 75+-30 and 200+-80 Bq m sup - sup 3...

  12. Seasonal variation of radon level and radon effective doses in the ...

    Indian Academy of Sciences (India)

    Inhalation of radon has been recognized as a health hazard. In the present work radon concentration was measured, in the atmosphere of the archaeological place, namely Catacomb of Kom El-Shuqafa, in Alexandria, Egypt, which is open to the public, using time-integrated passiveradon dosimeters containing LR-115 ...

  13. RADON REDUCTION AND RADON-RESISTANT CONSTRUCTION DEMONSTRATIONS IN NEW YORK - VOLUME 2: APPENDICES

    Science.gov (United States)

    Growing concern about health risks associated with exposure to indoor radon, a radioactive gas found in varying amounts in nearly all houses, has underscored the need for dependable radon reduction methods in existing and newly constructed houses. Responding to this need, the U....

  14. CO2-ECBM related coupled physical and mechanical transport processes

    Science.gov (United States)

    Gensterblum, Yves; Satorius, Michael; Busch, Andreas; Krooß, Bernhard

    2013-04-01

    The interrelation of cleat transport processes and mechanical properties was investigated by permeability tests at different stress levels (60% to 130% of in-situ stress) with sorbing (CH4, CO2) and inert gases (N2, Ar, He) on a sub bituminous A coal from the Surat Basin, Queensland Australia. From the flow tests under controlled triaxial stress conditions the Klinkenberg-corrected "true" permeability coefficients and the Klinkenberg slip factors were derived. The "true"-, absolute or Klinkenberg corrected permeability shows a gas type dependence. Following the approach of Seidle et al. (1992) the cleat volume compressibility (cf) was calculated from observed changes in apparent permeability upon variation of external stress (at equal mean gas pressures). The observed effects also show a clear dependence on gas type. Due to pore or cleat compressibility the cleat aperture decreases with increasing effective stress. Vice versa we observe with increasing mean pressure at lower confining pressure an increase in permeability which we attribute to a cleat aperture widening. The cleat volume compressibility (cf) also shows a dependence on the mean pore pressure. Non-sorbing gases like helium and argon show higher apparent permeabilities than sorbing gases like methane. Permeability coefficients measured with successively increasing mean gas pressures were consistently lower than those determined at decreasing mean gas pressures. This permeability hysteresis is in accordance with results reported by Harpalani and McPherson (1985). The kinetics of matrix transport processes were studied by sorption tests on different particle sizes at various moisture contents and temperatures (cf. Busch et al., 2006). Methane uptake rates were determined from the pressure decline curves recorded for each particle-size fraction, and "diffusion coefficients" were calculated using several unipore and bidisperse diffusion models. While the CH4 sorption capacity of moisture-equilibrated coals

  15. System of Systems Engineering and Integration Process for Network Transport Assessment

    Science.gov (United States)

    2016-09-01

    through the process to ensure oversight of design and tradeoff decisions for network throughput analyses. 14. SUBJECT TERMS network transport , SoS... Distribution is unlimited. SYSTEM OF SYSTEMS ENGINEERING AND INTEGRATION PROCESS FOR NETWORK TRANSPORT ASSESSMENT Matthew B. Rambo Civilian...engineering processes to utilize to address network transport design and testing? 2. How can SoS data throughput requirements be identified and

  16. Radon exhalation study of manganese clay residue and usability in brick production.

    Science.gov (United States)

    Kovács, Tibor; Shahrokhi, Amin; Sas, Zoltán; Vigh, Tamás; Somlai, János

    2017-03-01

    The reuse of by-products and residue streams is an important topic due to environmental and financial aspects. Manganese clay is a residue of manganese ore processing and is generated in huge amounts. This residue may contain some radionuclides with elevated concentrations. In this study, the radon emanation features and the massic exhalation rate of the heat-treated manganese clay were determined with regard to brick production. From the manganese mud depository, 20 samples were collected and after homogenization radon exhalation characteristics were determined as a function of firing temperatures from 100 to 750 °C. The major naturally occurring radionuclides 40 K, 226 Ra and 232 Th concentrations were 607 ± 34, 52 ± 6 and 40 ± 5 Bq kg -1 , respectively, comparable with normal clay samples. Similar to our previous studies a strong correlation was found between the internal structure and the radon emanation. The radon emanation coefficient decreased by ∼96% from 0.23 at 100 °C to 0.01 at 750 °C. The massic radon exhalation rate of samples fired at 750 °C reduced by 3% compared to samples fired at 100 °C. In light of the results, reusing of manganese clay as a brick additive is possible without any constraints. Copyright © 2016 Elsevier Ltd. All rights reserved.

  17. Exposure of volunteers to a radon progeny enriched atmosphere; Exposition von freiwilligen Probanden in einer an Radonzerfallsprodukten angereicherten Atmosphaere

    Energy Technology Data Exchange (ETDEWEB)

    Butterweck-Dempewolf, G.; Schuler, C.; Vezzu, G. [Paul Scherrer Inst. (PSI), Villigen (Switzerland)

    1998-12-31

    For an improvement of dose estimation of the exposure by inhalation of radon progeny in the domestic environment human volunteers were exposed to precisely determined radon progeny atomospheres in the walk-in radon chamber at the Paul Scherrer Institut (PSI). One of the major targets of the experiments consists of the determination of the transport rate of the short-lived radon progeny from the respiratory tract into the blood circuit. The question is, if this transport may be fast enough compared to the physical half-life of the radon progeny to have a significant influence on dose considerations. The experimental set-up consisting of measurement devices for the size distribution of the unattached radon progeny during the exposure and for the activity of the radon progeny in the blood circuit is described. First volunteers have been exposed to atomspheres with a large fraction of unattached radon progeny. From these measurements, a larger transfer rate of the unattached radon progeny from respiratory tract to the blood circuit than reported in the literature can be derived, but without reaching values significantly influencing dose estimations. (orig.) [Deutsch] Mit dem Ziel, die Inhalationsdosis der Radonzerfallsprodukte im haeuslichen Umfeld besser abschaetzen zu koennen, wurden freiwillige Probanden in der begehbaren Radonkammer des Paul Scherrer Instituts (PSI) einer sehr genau bekannten Radonzerfallsproduktsatmosphaere ausgesetzt. Eines der Hauptziele dieser Experimente betrifft den Transport der kurzlebigen Radonzerfallsprodukte vom Atmungstrakt in den Blutkreislauf. Beantwortet werden soll die Frage, ob dieser Transport verglichen mit der physikalischen Halbwertzeit dieser Nuklide schnell genug sein koennte, um einen dosisrelevanten Einfluss zu haben. Der experimentelle Aufbau, bestehend aus Apparaturen fuer die Messung der Groessenverteilung des unangelagerten Anteils der Radonzerfallsprodukte waehrend der Expositionen und der Aktivitaet im Blutkreislauf

  18. Radon exhalation rates of some granites used in Serbia

    Directory of Open Access Journals (Sweden)

    Nikolić Mladen D.

    2015-01-01

    Full Text Available In order to address concern about radon exhalation in building material, radon exhalation rate was determined for different granites available on Serbian market. Radon exhalation rate, along with mass exhalation rate and effective radium content were determined by closed chamber method and active continuous radon measurement technique. For this research, special chambers were made and tested for back diffusion and leakage, and the radon concentrations measured were included in the calculation of radon exhalation. The radon exhalation rate ranged from 0.161 Bq/m2h to 0.576 Bq/m2h, the mass exhalation rate from 0.167 Bq/kgh to 0.678 Bq/kgh, while the effective radium content was found to be from 12.37 Bq/kg to 50.23 Bq/kg. The results indicate that the granites used in Serbia have a low level of radon exhalation.

  19. How to Ensure Low Radon Concentrations in Indoor Environments

    DEFF Research Database (Denmark)

    Rasmussen, Torben Valdbjørn; Wraber, Ida Kristina

    2011-01-01

    This paper focuses on methods for measuring radon levels in the indoor air in buildings as well as on concrete solutions that can be carried out in the building to prevent radon leakage and to lower the radon concentration in the indoor air of new buildings. The radon provision in the new Danish...... Building Regulations from 2010 has been tightened as a result of new recommendations from the World Health Organization. Radon can cause lung cancer and it is not known whether there is a lower limit for its harmfulness. It is therefore important to reduce the radon concentration as much as possible in new...... buildings. The airtightness is a major factor when dealing with radon in buildings. Above the ground it is important to build airtight in compliance with energy requirements and against the ground it is important to prevent radon from seeping into the building. There is a direct connection between...

  20. Measurement of radon diffusion length in thin membranes.

    Science.gov (United States)

    Malki, A; Lavi, N; Moinester, M; Nassar, H; Neeman, E; Piasetzky, E; Steiner, V

    2012-07-01

    Building regulations in Israel require the insulating of buildings against radon (222)Rn penetration from soil. In radon-prone areas membranes stretched between the soil and the building foundation are used, together with sealing other possible penetration routes. Designing the radon mitigation procedure requires checking that all sealing materials are practically, radon tight, having a thickness of at least three times the radon diffusion length. In this work, a very simple technique to evaluate the radon diffusion length in thin membranes, using a radon source of known activity and an activated charcoal canister as radon detector is presented. The theoretical formalism and measurement results for polyethylene membranes of different densities obtained in a recent comparison exercise are presented.

  1. The imprint of thermally induced devolatilization phenomena on radon signal: implications for the geochemical survey in volcanic areas

    Science.gov (United States)

    Mollo, Silvio; Tuccimei, Paola; Galli, Gianfranco; Iezzi, Gianluca; Scarlato, Piergiorgio

    2017-10-01

    Thermal gradients due to magma dynamics in active volcanic areas may affect the emanating power of the substrate and the background level of radon signal. This is particularly effective in subvolcanic substrates where intense hydrothermal alteration and/or weathering processes generally form hydrous minerals, such as zeolites able to store and release great amounts of H2O (up to ˜25 wt.%) at relative low temperatures. To better understand the role played by thermally induced devolatilization reactions on the radon signal, a new experimental setup has been developed for measuring in real time the radon emission from a zeolitized volcanic tuff. Progressive dehydration phenomena with increasing temperature produce radon emissions two orders of magnitude higher than those measured during rock deformation, microfracturing and failure. In this framework, mineral devolatilization reactions can contribute significantly to produce radon emissions spatially heterogeneous and non-stationary in time, resulting in a transient state dictated by temperature gradients and the carrier effects of subsurface gases. Results from these experiments can be extrapolated to the temporal and spatial scales of magmatic processes, where the ascent of small magma batches from depth causes volatile release due to dehydration phenomena that increase the radon signal from the degassing host rock material.

  2. A finite element model development for simulation of the impact of slab thickness, joints, and membranes on indoor radon concentration.

    Science.gov (United States)

    Muñoz, E; Frutos, B; Olaya, M; Sánchez, J

    2017-10-01

    The focus of this study is broadly to define the physics involved in radon generation and transport through the soil and other materials using different parameter-estimation tools from the literature. The effect of moisture in the soil and radon transport via water in the pore space was accounted for with the application of a porosity correction coefficient. A 2D finite element model is created, which reproduces the diffusion and advection mechanisms resulting from specified boundary conditions. A comparison between the model and several analytical and numerical solutions obtained from the literature and field studies validates the model. Finally, the results demonstrate that the model can predict radon entry through different building boundary conditions, such as concrete slabs with or without joints, variable slab thicknesses and diffusion coefficients, and the use of several radon barrier membranes. Cracks in the concrete or the radon barrier membrane have been studied to understand how indoor concentration is affected by these issues. Copyright © 2017 Elsevier Ltd. All rights reserved.

  3. Radon in the groundwater of Muehlviertel (Upper Austria); Radon im Grundwasser des Muehlviertels (Oberoesterreich)

    Energy Technology Data Exchange (ETDEWEB)

    Schubert, Gerhard [Geologische Bundesanstalt, Wien (Austria). Abteilung Hydrogeologie; Alletsgruber, Irene [Triassic Geological Services, Northgate, Qld (Australia); Finger, Friedrich; Lettner, Herbert [Universitaet Salzburg (Austria). Fachbereich Materialforschung und Physik; Gasser, Veronika [Hydrogeologie Bohrwesen GmbH, Ferlach (Austria); Hobiger, Gerhard [Geologische Bundesanstalt, Wien (Austria). Abteilung Geochemie

    2010-03-15

    In the occurrence areas of selected crystalline rocks - mainly granites - the Radon-222 content of groundwater has been investigated. The results show a significant correlation with the Uranium concentrations in the rocks. The Uranium concentrations were between 1 and 15 ppm, while the Radon-222 concentrations were between 0.2 and 719.5 Bq/l. To identify Radon-decreasing effects like degasification and admixture of surface water, CO{sub 2} partial pressures and Oxygen-18 in water samples were determined and the local hydrological situation has been taken under consideration. Samples which showed clear evidence of Radon-decreasing effects were excluded from further evaluation because they would not represent the full empiric potential of Radon emanation in the aquifer. In combination with geological maps, petrologic information and airborne radiometry, Radon-222 analyses in groundwater can provide important data for Radon potential mapping. The significance of the groundwater Radon analyses can be improved by supplementary hydrochemical and hydrological isotope investigations. (orig.) [German] Im Muehlviertel wurde im Verbreitungsgebiet ausgewaehlter, gut definierter kristalliner Gesteine - vorwiegend Granite - das lokale Grundwasser gezielt auf Radon-222 beprobt. Das Ergebnis zeigt einen signifikanten Zusammenhang zwischen dem Urangehalt der Gesteine und dem Radongehalt der Grundwaesser auf. Die Messwerte lagen zwischen 1 und 15 ppm Uran im Gestein und zwischen 0,2 und 719,5 Bq/l Radon-222 im Grundwasser. Um im beprobten Grundwasser einen moeglichen Oberflaecheneinfluss, der den Radon-222-Gehalt herabsetzen wuerde, weitgehend ausschliessen zu koennen, wurde auch der CO{sub 2}-Partialdruck und der Sauerstoff-18-Gehalt bestimmt und die waehrend der Beprobung herrschende hydrologische Situation beruecksichtigt. Jene Proben, bei denen sich ein deutlicher Oberflaecheneinfluss abzeichnete, wurden nicht in die Auswertung mit einbezogen, da sie nicht das volle empirische

  4. Radon measures in the campus University of Alicante; Medidas de radon en el Campus de la Universidad de Alicante

    Energy Technology Data Exchange (ETDEWEB)

    Piedecausa Garcia, B.

    2013-07-01

    The aim of this work is the analysis and measurement the concentration of radon in underground spaces inside various buildings of the Campus of the University of Alicante, in order to determine the concentration of radon in existing facilities. (Author)

  5. Regulation of transport processes across the tonoplast membrane

    Directory of Open Access Journals (Sweden)

    Oliver eTrentmann

    2014-09-01

    Full Text Available In plants, the vacuole builds up the cellular turgor and represents an important component in cellular responses to diverse stress stimuli. Rapid volume changes of cells, particularly of motor cells, like guard cells, are caused by variation of osmolytes and consequently of the water contents in the vacuole. Moreover, directed solute uptake into or release out of the large central vacuole allows adaptation of cytosolic metabolite levels according to the current physiological requirements and specific cellular demands. Therefore, solute passage across the vacuolar membrane, the tonoplast, has to be tightly regulated. Important principles in vacuolar transport regulation are changes of tonoplast transport protein abundances by differential expression of genes or changes of their activities, e.g. due to post-translational modification or by interacting proteins. Because vacuolar transport is in most cases driven by an electro-chemical gradient altered activities of tonoplast proton pumps significantly influence vacuolar transport capacities. Intense studies on individual tonoplast proteins but also unbiased system biological approaches have provided important insights into the regulation of vacuolar transport. This short review refers to selected examples of tonoplast proteins and their regulation, with special focus on protein phosphorylation.

  6. Radon Measurements in Ghana: Health Risk Assessment at the ...

    African Journals Online (AJOL)

    The need to assess the risk of exposure to radon and its daughters stems from the reality that radon is a potential carcinogenic. We report Radon-222 risk assessment, from measurements on soil and sediments taken from six towns along the Lake Bosomtwi basin at two levels of 10cm and 20 cm. The current and future ...

  7. The latest trend of the research on radon

    Energy Technology Data Exchange (ETDEWEB)

    Kojima, Hiroshi [Science Univ. of Tokyo, Noda, Chiba (Japan). Faculty of Science and Technology

    1996-12-01

    In June, 1995, the international conference of sixth Natural Radiation Environment was held in Montreal. More than 80% of more than 200 published researches were concerned with radon and thoron. The participants came from 32 countries. The classification of the research on radon and the number of the publication are shown. The contents of the researches in respective items of measuring method, concentration level and dose evaluation, indoor model and indoor and outdoor radon balance, the countermeasures for reducing indoor radon, radon potential, dose evaluation model, the particle size distribution of aerosol including the particle size distribution of free daughter nuclides and radon in the atmosphere are described. The research on the radon in water is excluded. The most remarkable trend is the theme of radon potential. The trend of connecting the research on radon in soil and the research on dissipation rate to radon potential and the forecast of indoor and outdoor radon concentration seems to become stronger. As to the research on concentration level, the detection of hot spots and the supplementary measurement for clarifying cause are carried out in the advanced countries concerning radon based on the results of survey in whole country. The researches in schools are conspicuous. (K.I.)

  8. Estimation of radon concentration in dwellings in and around ...

    Indian Academy of Sciences (India)

    It has been established that radon and its airborne decay products can present serious radiation hazards. A long term exposure to high concentration of radon causes lung cancer. Besides, it is also known that out of the total radiation dose received from natural and man-made sources, 60% of the dose is due to radon.

  9. Estimation of radon concentration in dwellings in and around ...

    Indian Academy of Sciences (India)

    It has been established that radon and its airborne decay products can present serious radiation hazards. A long term exposure to high concentration of radon causes lung cancer. Besides, it is also known that out of the total radiation dose received from natural and man-made sources, 60% of the dose is due to radon and ...

  10. Measurement of radon exhalation rate in various building materials ...

    Indian Academy of Sciences (India)

    Indoor radon is considered as one of the potential dangerous radioactive elements. Common building materials and soil are the major source of this radon gas in the indoor environment. In the present study, the measurement of radon exhalation rate in the soil and building material samples of Una and Hamirpurdistricts of ...

  11. Determination of radon gas and respirable ore dust concentrations ...

    African Journals Online (AJOL)

    This study has estimated the concentrations of radon gas and respirable ore dust in the Merelani underground tanzanite mines. Two different portable monitors were used to measure the radon gas and respirable ore dust concentrations respectively. The mean radon gas concentration (disintegrations per second per cubic ...

  12. RESOLVING THE RADON PROBLEM IN CLINTON, NEW JERSEY HOUSES

    Science.gov (United States)

    The paper discusses the resolution of a radon problem in Clinton, New Jersey, where significantly elevated radon concentrations were found in several adjacent houses. The U.S. EPA screened 56 of the houses and selected 10 for demonstration of radon reduction techniques. Each of t...

  13. Assessment of indoor radon gas concentration change of college

    Energy Technology Data Exchange (ETDEWEB)

    Park, Hoon Hee; Jeong, Eui Hwan; Kim, Hak Jae; Lyu, Kang Yeul [Dept. of of Radiological Technology, Shingu College, Seongnam (Korea, Republic of); Lee, Ju Young [Dept. of Radiological Technology, Songho College, Hoengseong (Korea, Republic of)

    2017-03-15

    The purpose of this study was to assess the impact by comparing the concentration of indoor radon and look for ways to lower the concentration of indoor radon gas measurements of three variables, the year of completion, volume of the building and ventilation. Measurement target is six classrooms on the sixth floor of building that was constructed in 1973 and was extended in 2011. Selected classroom's volume is different. Four classrooms were selected to compare the radon concentration in accordance with the year of completion, Classrooms that is same year of completion were selected to compare the radon concentration in accordance with the volume, six classroom was performed closure and ventilation to compare radon concentration according to ventilation. Radon concentrations in accordance with the year of building completion showed a high concentration of radon in a building recently built. Also, Radon concentration in volume is high the smaller the volume. Radon concentration change according to ventilation showed a reduction of about 80% when the ventilation than during closing. Especially, The radon concentrations were high detected while the recently year of building completion and the smaller volume. Ventilation of the three variables is considered that can be expected to exposure reduction effect by radon affecting the greatest radon concentration reduction.

  14. State transportation policy initiative : a new strategic urban transportation planning process

    Science.gov (United States)

    1995-06-01

    Recent legislation and fiscal trends in Florida and nationwide have created a unique combination of constraints and opportunities, providing an impetus for examining the way Florida conducts transportation planning. In response to these challenges, t...

  15. Processes of technology assessment: The National Transportation Safety Board

    Science.gov (United States)

    Weiss, E.

    1972-01-01

    The functions and operations of the Safety Board as related to technology assessment are described, and a brief history of the Safety Board is given. Recommendations made for safety in all areas of transportation and the actions taken are listed. Although accident investigation is an important aspect of NTSB's activity, it is felt that the greatest contribution is in pressing for development of better accident prevention programs. Efforts of the Safety Board in changing transportation technology to improve safety and prevent accidents are illustrated.

  16. Reported Design Processes for Accessibility in Rail Transport

    DEFF Research Database (Denmark)

    Herriott, Richard; Cook, Sharon

    2014-01-01

    requirements with the aim of maximising accessibility in products and services. A review of ID literature has mainly developed in the arena of product design and design for assistive technology. Accessibility is a fundamental requirement in public transport (PT) yet there exists little research on design...... for accessibility or ID in this area. How is accessibility and the needs of users accounted for in rail transport design? This paper analyses interviews with rolling stock producers, operators and design consultancies. These conducted to determine if ID design methods are used explicitly and the extent to which...

  17. Radon as a groundwater tracer in Forsmark and Laxemar

    Energy Technology Data Exchange (ETDEWEB)

    Grolander, Sara

    2009-10-15

    Radon concentrations were measured in different water types in Forsmark and Laxemar during the site investigation and within this study. From these measurements it can be concluded that large differences between surface water, near surface groundwater and deep groundwater can be found in both Laxemar and Forsmark. The differences in radon concentrations between different water types are used in this study to detect interactions between surface water, near surface water and deep groundwater. From the radon measurements it can also be concluded that radon concentration in deep groundwater varies largely with depth. These variations with depth are probably caused by groundwater flow in conductive fracture zones in the bedrock. The focus of this study has been the radon concentration of near surface groundwater and the interaction between near surface groundwater and deep groundwater. Radon measurements have been done using the RAD-7 radon detector within this study. It could be concluded that RAD-7 is a good technique for radon measurements and also easy to use in field. The radon concentrations measured in near surface groundwater in Laxemar within this study were low and homogenous. The variation in radon concentration has been analyses and compared to other parameters. Since the hypothesis of this study has been that there are differences in radon concentrations between recharging and discharging groundwater, the most important parameter to consider is the recharge/discharge field classification of the wells. No correlation between the recharge/discharge classifications of wells and the radon concentrations were found. The lack of correlation between groundwater flow patterns and radon concentration means that it is not possible to detect flow patterns in near surface groundwater using radon as a tracer in the Laxemar area. The lack of correlation can be caused by the fact that there are just a few wells located in areas classified as recharge area. It can also be

  18. Radon in soil gas in Kosovo.

    Science.gov (United States)

    Kikaj, Dafina; Jeran, Zvonka; Bahtijari, Meleq; Stegnar, Peter

    2016-11-01

    An assessment of the radiological situation due to exposure to radon and gamma emitting radionuclides was conducted in southern Kosovo. This study deals with sources of radon in soil gas. A long-term study of radon concentrations in the soil gas was carried out using the SSNTDs (CR-39) at 21 different locations in the Sharr-Korabi zone. The detectors were exposed for an extended period of time, including at least three seasonal periods in a year and the sampling locations were chosen with respect to lithology. In order to determine the concentration of the natural radioactive elements 238 U and 226 Ra, as a precursor of 222 Rn, soil samples were collected from each measuring point from a depth of 0.8 m, and measured by gamma spectrometry. The levels (Bq kg -1 ) of naturally occurring radionuclides and levels (kBq m -3 ) of radon in soil gas obtained at a depth 0.8 m of soil were: 21-53 for 226 Ra, 22-160 for 238 U and 0.295-32 for 222 Rn. With respect to lithology, the highest value for 238 U and 226 Ra were found in limestone and the highest value for 222 Rn was found in metamorphic rocks. In addition, the results showed seasonal variations of the measured soil gas radon concentrations with maximum concentration in the spring months. Copyright © 2016 Elsevier Ltd. All rights reserved.

  19. Radon background study in Super-Kamiokande

    Science.gov (United States)

    Nakano, Yuuki; Super-Kamiokande Collaboration

    2017-09-01

    Super-Kamiokande (SK), a 50 kton water Cherenkov detector in Japan, observes 8B solar neutrinos with neutrino-electron elastic scattering. SK searches for distortions of the solar neutrino energy spectrum caused by the edge of the MSW resonance in the core of the Sun. The installation of new front-end electronics in 2008 marks the beginning of the 4th phase of SK (SK-IV). With the improvement of the water circulation system, calibration methods, reduction cuts, this phase achieved the lowest energy threshold thus far (3.5 MeV kinetic energy). To improve the sensitivity to the MSW effect, it is required to achieve lower energy threshold. For this purpose, understanding the origin of background events and reducing them are important. Currently, the main background is known as a beta decay of 214Bi in a Radon decay chain. So far, SK collaboration has developed several techniques for studying Radon contamination in the SK water. In this proceedings, a measurement system which can measure Radon concentration in the SK water with the accuracy of 0.1 mBq/m3 level is presented. In addition, an evaluation of Radon background events in SK injecting Radon rich water into the SK tank, as well as future prospects are also presented.

  20. RADON MITIGATION IN SCHOOLS: CASE STUDIES OF RADON MITIGATION SYSTEMS INSTALLED BY EPA IN FOUR MARYLAND SCHOOLS ARE PRESENTED

    Science.gov (United States)

    The first part of this two-part paper discusses radon entry into schools, radon mitigation approaches for schools, and school characteristics (e.g., heating, ventilation, and air-conditioning -- HVAC-- system design and operation) that influence radon entry and mitigation system ...

  1. Underground Coal Gasification: Rates of Post Processing Gas Transport

    Czech Academy of Sciences Publication Activity Database

    Soukup, Karel; Hejtmánek, Vladimír; Stanczyk, K.; Šolcová, Olga

    2014-01-01

    Roč. 68, č. 12 (2014), s. 1707-1715 ISSN 0366-6352 R&D Projects: GA MŠk 7C12017 Grant - others:RFCS(XE) RFCR-CT-2011-00002 Institutional support: RVO:67985858 Keywords : underground coal gasification * gas transport * textural properties Subject RIV: CI - Industrial Chemistry, Chemical Engineering Impact factor: 1.468, year: 2014

  2. Partial ages : Diagnosing transport processes by means of multiple clocks

    NARCIS (Netherlands)

    Mouchet, A.; Cornaton, F.; Deleersnijder, E.L.C.; Delhez, E.J.M.

    2016-01-01

    The concept of age is widely used to quantify the transport rate of tracers - or pollutants - in the environment. The age focuses only on the time taken to reach a given location and disregards other aspects of the path followed by the tracer parcel. To keep track of the subregions visited by the

  3. Continuous phosphorus measurements reveal catchment-scale transport processes

    NARCIS (Netherlands)

    Velde, Y. van der; Rozemeijer, J.C.

    2012-01-01

    A small fraction of the nutrients used for agriculture is transported by rivers and artificial drainage networks to downstream waters. In lakes and coastal seas such as the Baltic Sea and the Gulf of Mexico these nutrients cause large-scale algal blooms and hypoxia and thus are a major

  4. Scaling and predicting solute transport processes in streams

    Science.gov (United States)

    R. González-Pinzón; R. Haggerty; M. Dentz

    2013-01-01

    We investigated scaling of conservative solute transport using temporal moment analysis of 98 tracer experiments (384 breakthrough curves) conducted in 44 streams located on five continents. The experiments span 7 orders of magnitude in discharge (10-3 to 103 m3/s), span 5 orders of magnitude in...

  5. Benthic processes affecting contaminant transport in Upper Klamath Lake, Oregon

    Science.gov (United States)

    Kuwabara, James S.; Topping, Brent R.; Carter, James L.; Carlson, Rick A; Parchaso, Francis; Fend, Steven V.; Stauffer-Olsen, Natalie; Manning, Andrew J.; Land, Jennie M.

    2016-09-30

    Executive SummaryMultiple sampling trips during calendar years 2013 through 2015 were coordinated to provide measurements of interdependent benthic processes that potentially affect contaminant transport in Upper Klamath Lake (UKL), Oregon. The measurements were motivated by recognition that such internal processes (for example, solute benthic flux, bioturbation and solute efflux by benthic invertebrates, and physical groundwater-surface water interactions) were not integrated into existing management models for UKL. Up until 2013, all of the benthic-flux studies generally had been limited spatially to a number of sites in the northern part of UKL and limited temporally to 2–3 samplings per year. All of the benthic invertebrate studies also had been limited to the northern part of the lake; however, intensive temporal (weekly) studies had previously been completed independent of benthic-flux studies. Therefore, knowledge of both the spatial and temporal variability in benthic flux and benthic invertebrate distributions for the entire lake was lacking. To address these limitations, we completed a lakewide spatial study during 2013 and a coordinated temporal study with weekly sampling of benthic flux and benthic invertebrates during 2014. Field design of the spatially focused study in 2013 involved 21 sites sampled three times as the summer cyanobacterial bloom developed (that is, May 23, June 13, and July 3, 2013). Results of the 27-week, temporally focused study of one site in 2014 were summarized and partitioned into three periods (referred to herein as pre-bloom, bloom and post-bloom periods), each period involving 9 weeks of profiler deployments, water column and benthic sampling. Partitioning of the pre-bloom, bloom, and post-bloom periods were based on water-column chlorophyll concentrations and involved the following date intervals, respectively: April 15 through June 10, June 17 through August 13, and August 20 through October 16, 2014. To examine

  6. System of business-processes management at motor-transport enterprise

    OpenAIRE

    Коgut, Y.

    2010-01-01

    The place of the system of business-processes management at motor-transport enterprise in the general system of management of the enterprise has been substantiated. The subsystems of strategic management, business-processes management of strategic orientation and current activity, processes of enterprise functioning management have been marked out. The system of motor-transport enterprise business-processes management has been formed, which, unlike the existing ones, is based on the system-cy...

  7. The use of track registration detectors to reconstruct contemporary and historical airborne radon ( sup 2 sup 2 sup 2 Rn) and radon progeny concentrations for a radon-lung cancer epidemiologic study

    CERN Document Server

    Steck, D J

    1999-01-01

    Epidemiologic studies that investigate the relationship between radon and lung cancer require accurate estimates for the long-term average concentrations of radon progeny in dwellings. Year-to-year and home-to-home variations of radon in domestic environments pose serious difficulties for reconstructing an individual's long-term radon-related exposure. The use of contemporary radon gas concentrations as a surrogate for radon-related dose introduces additional uncertainty in dose assessment. Studies of glass exposed in radon chambers and in a home show that radon progeny deposited on, and implanted in, glass hold promise for reconstructing past radon concentrations in a variety of atmospheres. We developed an inexpensive track registration detector for the Iowa Radon Lung Cancer Study (IRLCS) that simultaneously measures contemporary airborne radon concentrations, surface deposited alpha activity density, and implanted sup 2 sup 1 sup 0 Po activity density. The implanted activity is used to reconstruct the cum...

  8. The European radon mapping project

    Energy Technology Data Exchange (ETDEWEB)

    Bossew, P., E-mail: pbossew@bfs.de [German Federal Office for Radiation Protection, Berlin (Germany); Tollefsen, T.; Gruber, V.; De Cort, M., E-mail: tore.tollefsen@jrc.ec.europa.eu, E-mail: valeria.gruber@gmail.com, E-mail: marc.de-cort@jrc.ec.europa.eu [Institute for Transuranium Elements, Ispra, VA (Italy). DG Joint Research Centre. European Commission

    2013-07-01

    There is almost unanimous agreement that indoor radon (Rn) represents a hazard to human health. Large-scale epidemiological studies gave evidence that Rn is the second-most important cause o flung cancer after smoking and that also relatively low Rn concentrations can be detrimental. This has increasingly led to attempts to limit Rn exposure through regulation, mainly building codes. The proposed Euratom Basic Safety Standards (BSS) require Member States to establish Rn action plans aimed at reducing Rn risk, and to set reference values for Imitating indoor Rn concentration. In 2006 the JRC started a project on mapping Rn at the European level, in addition and complementary lo (but not as a substitute for) national efforts. These maps are part of the European Atlas of Natural Radiation project. which is planned eventually 10 comprise geographical assessments of ali sources of exposure to natural radiation. Started first, a map of indoor Rn is now in an advanced phase, but still incomplete as national Rn surveys are ongoing in a number of European countries. A European map of geogenic Rn, conceptually and technically more complicated, was started in 2008. The main difficulty encountered is heterogeneity of survey designs, measurement and evaluation methods and database semantics and structures. An important part or the work on the Atlas is therefore to harmonize data and methods. We present the current state of the Rn maps and discuss some of the methodological challenges. (author)

  9. Residential radon in Finland: sources, variation, modelling and dose comparisons

    Energy Technology Data Exchange (ETDEWEB)

    Arvela, H.

    1995-09-01

    The study deals with sources of indoor radon in Finland, seasonal variations in radon concentration, the effect of house construction and ventilation and also with the radiation dose from indoor radon and terrestrial gamma radiation. The results are based on radon measurements in approximately 4000 dwellings and on air exchange measurements in 250 dwellings as well as on model calculations. The results confirm that convective soil air flow is by far the most important source of indoor radon in Finnish low-rise residential housing. (97 refs., 61 figs., 30 tabs.).

  10. Indoor radon and decay products: Concentrations, causes, and control strategies

    Energy Technology Data Exchange (ETDEWEB)

    Nero, A.V.; Gadgil, A.J.; Nazaroff, W.W.; Revzan, K.L.

    1990-11-01

    This report is another in the on going technical report series that addresses various aspects of the DOE Radon Research Program. It provides an overview of what is known about the behavior of radon and its decay products in the indoor environment and examines the manner in which several important classes of factors -- structural, geological, and meteorological -- affect indoor radon concentrations. Information on US indoor radon concentrations, currently available monitoring methods and novel radon control strategies are also explored. 238 refs., 22 figs., 9 tabs.

  11. Radon atlas of England and Wales

    Energy Technology Data Exchange (ETDEWEB)

    Green, B.M.R.; Miles, J.C.H.; Bradley, E.J.; Rees, D.M

    2002-07-01

    This new report brings together and updates the information in three earlier reports on radon levels in English and Welsh homes. In particular, data from measurements in over 400,000 homes in England and Wales are presented in tabular format. The tables give the data by various administrative divisions, down to electoral wards for Cornwall, Devon and Somerset and council areas elsewhere and to sector level of the postcode system. The radon probability maps are based on the national grid system and show significantly more locational detail than the previous publications, an extra division in the probability banding to coincide with current Government initiatives on radon in England and, in southwest England, more detailed probability mapping than before - by 1 km grid squares in place of the 5 km grid squares used in Wales and the rest of England. (author)

  12. Magnetosheath excursion and the relevant transport process at the magnetopause

    Directory of Open Access Journals (Sweden)

    C. L. Cai

    2009-08-01

    Full Text Available A large-amplitude excursion of the magnetosheath (MS in quiet solar wind conditions on 17 March 2004 was recorded simultaneously by the Cluster and TC-1 spacecraft. During this period, the IMF Bz was entirely northward. The coherence between the bow shock motion and magnetopause (MP motion is revealed and the excursion velocities of the bow shock motion are analyzed. In addition, the relevant plasma transport phenomenon in the form of flux fluctuations below the ion gyrofrequency at the MP is exposed and is interpreted as manifestation of the drift instability. Correlated observations on charge accumulation and electrostatic potential perturbation are recorded by electron measurements in high energy regime, and also the eventual cross-field vortex motion in the nonlinear stage and the consequential mass exchange are exhibited. The present investigation gives some new insight into the MS plasma transport mechanism across the subsolar MP region in quiet solar wind conditions during a period of northward IMF.

  13. Indoor radon measurements and radon prognosis for the province of Kymi, southeastern Finland; Huoneilman radonmittaukset Kymen laeaenissae: Tilannekatsaus ja radonennuste

    Energy Technology Data Exchange (ETDEWEB)

    Pennanen, M.; Maekelaeinen, I.; Voutilainen, A.

    1996-12-01

    The purpose of the regional radon prognosis is to classify areas with different levels of radon risk. The radon prognosis gives the percentages of future homes expected to have indoor radon concentrations exceeding the levels of 200 and 400 Bq/m{sup 3}. It is assumed that no protection against the entry of radon is used in construction. In this study about 5900 indoor radon measurements made in single family houses, semi-detached houses and row houses were used. Data on the location, geology and construction of buildings were determined from maps and questionnaires. An empirical statistical model, the adjusted indoor radon measurements and geological data were used to assess the radon risk from soil and bedrock in different areas. The building sites of the province of Kymi were divided into thirteen sub-areas. The radon prognosis are calculated for the most radon-prone foundation types including (1) houses with a slab-on-grade and (2) houses with a basement or hillside houses with open stairwells between basement and first floor. The radon levels are generally greater in the western part of the area. The radon risk is highest in gravel-dominated esker areas in southwestern, western (in Pyhtaa, Kotka, Anjalankoski, litti, Valkeala) and central (Taipalsaari) parts of the area. The radon risk is also high in some bedrock and till areas, also in southwestern and western parts of the area. In these areas the level of 200 Bq/m{sup 3} will be exceeded in 80 % of new houses. About half of the future houses in these areas will have indoor radon concentrations exceeding 400 Bq/m{sup 3}. The radon risk is lowest in the eastern part of the province of Kymi in every soil type. In this area the level of 200 Bq/m{sup 3} will be exceeded in 30 % of new houses. Below 10 % will exceed 400 Bq/m{sup 3}. (orig.) (14 refs.).

  14. Behavior of radon, chemical compounds and stable elements in underground water; Comportamiento de radon, compuestos quimicos y elementos estables en agua subterranea

    Energy Technology Data Exchange (ETDEWEB)

    Lopez R, N.; Segovia, N.; Lopez, M.B.E.; Pena, P. [Instituto Nacional de Investigaciones Nucleares, A.P. 18-1027, 11801 Mexico D.F. (Mexico); Armienta, M.A.; Godinez, L. [IGFUNAM, Ciudad Universitaria, 04510 Mexico D.F. (Mexico); Seidel, J.L. [ISTEEM, M.S.E. Montpellier (France)

    2001-07-01

    The radon behavior, chemical compounds, major and trace elements in water samples of four springs and three wells of urban and agricultural zones around the Jocotitlan volcano and El Oro region was determined, both of them located in the medium part of the Mexican neo-volcanic axis. The {sup 222} Rn was measured by the liquid scintillation method, the analysis of major components was realized with conventional chemical techniques, while the trace elements were quantified using an Icp-Ms. The average values of the radon concentrations obtained during one year were constant relatively, in an interval from 0.97 to 4.99 Bq/lt indicating a fast transport from the reload area toward the sampling points. the compounds, major and trace elements showed differences which indicate distinct origins of water from the site studies. (Author)

  15. Radon soil-gas concentration and exhalation from mine tailings dams in South Africa

    Energy Technology Data Exchange (ETDEWEB)

    Ongori, J.; Lindsay, R. [University of the Western Cape, Department of Physics, Private Bag X17, Bellville 7535 (South Africa); Newman, R. [Stellenbosch University, Department of Physics, Private Bag X1 Matieland 7602 (South Africa); Maleka, P. [iThemba LABS, Department of Nuclear Physics, P. O. Box 722, Somerset West 7129 (South Africa)

    2014-07-01

    In Africa as well as in the world, South Africa plays an important role in the mining industry which dates back almost 120 years. Mining activities in South Africa mainly take place in Gauteng Province. Every year million of tons of rocks are taken from underground, milled and processed to extract gold. The uranium bearing tailings are disposed in dumpsites. These tailings dumps contain considerable amounts of radium ({sup 226}Ra) and have therefore been identified as large sources of radon ({sup 222}Rn). Radon is a noble gas formed by the decay of radium which in turn is derived from the radioactive decay of uranium ({sup 238}U). Radon release from these tailings dumps pose health concerns for the surrounding communities. Radon soil gas concentrations and exhalations from a non-operational mine dump (Kloof) which belongs to Carletonville Gold Field, Witwatersrand, South Africa have been investigated. The continuous radon monitor, the Durridge RAD7 was used to measure {sup 222}Rn soil gas concentration in the tailings dump at five different spots. The radon soil gas concentration levels were measured at depths starting from 30 cm below ground/air interface up to 110 cm at intervals of 20 cm. The concentrations recorded ranged from 26±1 to 472±23 kBq.m{sup -3}. Furthermore, thirty four soil samples were taken from the spots where radon soil gas measurements were measured for laboratory-based measurement using the low background Hyper Pure Germanium (HPGe) gamma-ray detector available at the Environmental Radioactivity Laboratory (ERL), iThemba LABS, Western Cape Province. The soil samples were collected in the depth range 0-30 cm. After analysis the weighted average activity concentrations in the soils samples were 308±7 Bq.kg{sup -1}, 255±5 Bq.kg{sup -1} and 18±1 Bq.kg{sup -1} for {sup 238}U, {sup 40}K and {sup 232}Th, respectively. A number of factors such as the radium activity concentration and its distribution in soil grains, soil grain size, soil porosity

  16. The contribution of bedload transport processes to natural hazard damage costs in Switzerland

    Science.gov (United States)

    Andres, Norina; Badoux, Alexandre; Turowski, Jens

    2013-04-01

    In Alpine regions, floods are often associated with erosion along the stream channels and with bedload transport in mountain rivers. These bedload transport processes pose hazard in addition to the elevated water discharge. However, it is unclear how much bedload transport processes contribute to total damage caused by natural hazards, an information that may be vital for flood mitigation measures and for the design of protective infrastructure. Using the Swiss flood and landslide data base, which collects direct financial damage data of naturally triggered floods, debris flows and landslides since 1972, we estimated the contribution of bedload transport processes to total natural hazard damage costs in Switzerland. For each data base entry an upper and lower limit of financial damage caused by or related to fluvial bedload transport processes was estimated, and the quality of the estimate was judged. When compared to total damage, the fraction of bedload transport damage lies between 32 and 37% (lower and upper estimates). In the 40 year study period, the bedload transport processes have induced a cumulative financial damage between 4.3 and 5.1 billion CHF. Spatial analysis revealed highest damage for mountainous regions. The analysis of the seasonal distribution of bedload erosion and deposition shows that more than 75% of the costs occurs in summer (June through August), and ~23% in autumn (September through November). With roughly 56%, by far most of the damage has been registered in the month of August. In winter and spring damage due to bedload processes is very low. Despite more than a hundred years of research, bedload transport processes are inadequately understood, and the predictive quality of common bedload equations is still poor. The importance of bedload transport processes as a natural hazard and financial source of risk, and thus the need for future structured research programmes on transport processes in steep streams has been demonstrated in our

  17. Interplay of transporters and enzymes in drug and metabolite processing.

    Science.gov (United States)

    Pang, K Sandy; Maeng, Han-Joo; Fan, Jianghong

    2009-01-01

    This review highlights the "interplay" between enzymes and transporters, essential components of eliminating organs for drug removal. The understanding of the interplay is important in terms of deciphering the change of one eliminatory pathway on compensatory mechanisms in drug disposal, and, ultimately, their importance in drug-drug interactions. Controversy existed on the explanation underlying the interplay between transporters and enzymes in the Caco-2 cell monolayer or cell culture systems, but less so on eliminating organs such as the intestine and liver. For the Caco-2 system, the increase in the mean residence time (MRT) accompanying increased secretion had been construed as the basis for increased metabolism. We hold the opposite view and assert that increased secretion should evoke a decrease in metabolism due to the competition between the enzyme and apical efflux transporter for the drug within the cell. To illustrate this point, simulations on the MRT, fraction of dose metabolized (f(met)) and the extraction ratio (ER) as defined by various investigators under linear and nonlinear metabolic conditions were compared to observed data and the trends upon induction/inhibition of secretion. The conclusion is that the f(met) is the more appropriate index to reflect the extent of metabolism in transporter-enzyme interplay, since the parameter captures drug metabolism in the cell when its contents in the apical, cell, and basolateral compartments or the entire dose is considered to be available for metabolism. This parameter for metabolism (f(met)) bears a reciprocal relationship to the secretory intrinsic clearance and is in concordance with the notion that both the enzyme and apical transporter compete for the cellular substrate within. For the liver and intestine, several physiologically based pharmacokinetic (PBPK) models that contain transporters and enzymes were utilized, together with the solved equations for the area under the curve (AUC), metabolic

  18. Management of the process of nuclear transport; Gestion del proceso de transporte nuclear

    Energy Technology Data Exchange (ETDEWEB)

    Requejo, P.

    2015-07-01

    Since 1996 ETSA is the only Spanish logistics operator specialized on servicing the nuclear and radioactive industry. Nowadays ETSA has some technological systems specifically designed for the management of nuclear transports. These tools have been the result of the analysis of multiple factors involved in nuclear shipments, of ETSAs wide experience as a logistics operator and the search for continuous improvement. (Author)

  19. Indoor radon survey in dwellings of some regions in Yemen

    Energy Technology Data Exchange (ETDEWEB)

    Khayrat, A.H. E-mail: akhayrat@yahoo.com; Al-Jarallah, M.I.; Fazal-ur-Rehman, X.; Abu-Jarad, F

    2003-06-01

    Indoor radon survey in a total of 241 dwellings, distributed in some regions of Yemen was performed, using CR-39 based radon monitors. The objective of this radon survey is to get representative indoor radon data of three regions, namely Dhamar, Taiz and Hodeidah, situated at different altitudes above sea level. The radon concentrations varied from 3 to 270 Bq m{sup -3} with an average of 42 Bq m{sup -3}. It was found that the average radon concentration in the surveyed areas increases with altitudes. The highest average radon concentration of 59 Bq m{sup -3} was found in Dhamar city while the lowest average concentration of 8 Bq m{sup -3} was found in Hodeidah city.

  20. Radon in workplaces in Extremadura (Spain).

    Science.gov (United States)

    Sánchez, A Martín; Pérez, J de la Torre; Sánchez, A B Ruano; Correa, F L Naranjo

    2012-05-01

    Indoor radon measurements are usually associated with housing. However, a typical person spends about one-third of the day at their workplace. A survey was made of radon levels in workplaces in Extremadura (Spain). More than 200 measurements were performed in some 130 firms and organizations of different sectors (urban wellness centres, spas, caves, mines, water management facilities, underground carparks, wine cellars, museums, etc.). Activated charcoal canisters and track detectors were used for sampling. The results indicated the importance of performing this type of measurement because the exposure of workers can reach high values in some cases. Copyright © 2012 Elsevier Ltd. All rights reserved.

  1. Development of a quality assured calibration method for the PSI radon chamber reference atmosphere

    Energy Technology Data Exchange (ETDEWEB)

    Schuler, C.; Butterweck-Dempewolf, G.; Vezzu, G. [Paul Scherrer Inst. (PSI), Villigen (Switzerland)

    1997-08-01

    Radon detectors and measuring instruments are calibrated at the PSI Reference Laboratory for Radon Gas Concentration Measurements by exposing them to a calibrated radon reference atmosphere in the PSI radon chamber. A sophisticated and quality assured calibration technique was developed which guarantees the traceability of this radon chamber reference atmosphere to standards of internationally acknowledged primary laboratories. (author) 2 figs., 2 refs.

  2. Analysis and classification of bedload transport events with variable process characteristics

    Science.gov (United States)

    Kreisler, Andrea; Moser, Markus; Aigner, Johann; Rindler, Rolf; Tritthart, Michael; Habersack, Helmut

    2017-08-01

    Knowledge about the magnitude of bedload fluxes at given hydraulic conditions in natural streams is essential for improved process understanding, for the application, calibration and validation of bedload transport formulas, and for numerical sediment transport models. Nonetheless, extensive field measurements of bedload transport are challenging and therefore data from such efforts are rare. Bedload transport has been measured comprehensively at the downstream section of the Urslau torrent in Salzburg, Austria, since 2011. We used an integrative monitoring system that combines direct (mobile basket sampler, slot sampler) and indirect measuring devices (geophone plates). Continuous information about the intensity and distribution of bedload transport within the channel cross-section is available in high spatial and temporal resolution. Seven geophone plates at a stream width of 8 m are part of a measurement system that delivers data in 1-min intervals. These geophone data are calibrated using results of direct bedload measurements, providing an opportunity to calculate bedload rates and bedload yields in selected time periods. Continuous data on the bedload transport process over three years enabled assessing several bedload transport events. The investigation of bedload transport rate/discharge relationships reveals order-of-magnitude changes. For individual events, we observed shifts in the data, reflecting different bedload rates at comparable hydraulic conditions. This study reveals that variable sediment supply conditions affect the prevailing bedload transport rates at the Urslau stream. Calculating the bedload transport efficiency enables comparing bedload transport events that exhibit similar process characteristics. Finally, we provide a conceptual model of bedload transport process types as a function of bedload transport efficiency and dimensionless stream power.

  3. The role of confounding factors in a radon epidemiological study

    Directory of Open Access Journals (Sweden)

    A. D. Onishchenko

    2017-01-01

    Full Text Available Objective: A simulation of a large-scale epidemiological case-control study to identify the relationship between exposure to radon and lung cancer in the presence of factors that distort the results of the assessment of exposure to radon in homes. Materials and Methods: Analysis of sources of uncertainties arising during radon epidemiologic case-control studies. Evaluation of the uncertainties caused by the errors of the measurements of the long-term variations in the radon concentration, exposure to radon in other places of the human habitat, except dwellings, etc. Simulation by Monte Carlo technique of radon epidemiologic study, comparable to the combined European radon study, and assessment of uncertainties, which affect the evaluation of dose-effect dependence. Results: The multiplicative error in the assessment of individual exposure based on the radon concentration is shown generally caused by the combined effect of long-term variations of the radon concentration and the differences in the levels of the radon concentration in living houses and other places of the human habitat. The logarithmic standard deviation of this errors σerr is from 0,70 to 0,90. The estimated value of this error is 2,0 times higher than the value used for correction of the results of the combined European radon study. It is shown that for the σerr <0,9 regression calibration technique, there is a possibility to make a full correction of uncertainty. Conclusion: Errors in the assessment of uncertainties of the radon exposure based on the radon concentration in the combine European radon case-control study has led to an underestimation of the relative risk of lung cancer incidence at least with a factor of 1,5.

  4. Variations of radon concentration in the atmosphere. Gamma dose rate

    Science.gov (United States)

    Tchorz-Trzeciakiewicz, D. E.; Solecki, A. T.

    2018-02-01

    The purposes of research were following: observation and interpretation of variations of radon concentration in the atmosphere - vertical, seasonal, spatial and analysis of relation between average annual radon concentration and ground natural radiation and gamma dose rate. Moreover we wanted to check the occurrence of radon density currents and the possibility of radon accumulation at the foot of the spoil tip. The surveys were carried out in Okrzeszyn (SW Poland) in the area of the spoil tip formed during uranium mining that took place in 60's of 20th century. The measurements were carried out in 20 measurements points at three heights: 0.2 m, 1 m and 2 m a.g.l. using SSNTD LR-115. The survey lasted one year and detectors were exchanged at the beginning of every season. Uranium eU (ppm), thorium eTh (ppm) and potassium K (%) contents were measured using gamma ray spectrometer Exploranium RS-230, ambient gamma dose rate using radiometer RK-100. The average radon concentration on this area was 52.8 Bq m-3. The highest radon concentrations were noted during autumn and the lowest during winter. We observed vertical variations of radon concentration. Radon concentrations decreased with increase of height above ground level. The decrease of radon with increase of height a.g.l. had logarithmic character. Spatial variations of radon concentrations did not indicate the occurrence of radon density currents and accumulation of radon at the foot of the spoil tip. The analysis of relation between average radon concentrations and ground natural radiation (uranium and thorium content) or gamma dose rate revealed positive relation between those parameters. On the base of results mentioned above we suggested that gamma spectrometry measurements or even cheaper and simpler ambient gamma dose rate measurements can be a useful tool in determining radon prone areas. This should be confirmed by additional research.

  5. Occupational exposure to radon in Australian Tourist Caves an Australian-wide study of radon levels

    Energy Technology Data Exchange (ETDEWEB)

    Solomon, S.B.; Langroo, R.; Peggie, J.R. [Australian Radiation Laboratory. Yallambie, VIC (Australia); Lyons, R.G. [University of Auckland, Auckland, (New Zealand). Department of Physics; James, J.M. [University of Sydney, Sydney, NSW (Australia). Department of Chemisty

    1996-02-01

    The study described in this report sets out to determine which Australian show caves have long- term radon levels in excess of the proposed action level of 1000 Bq m{sup -3}. The collaborative study between the Australian Radiation Laboratory (ARL), the University of Sydney and the University of Auckland, was carried out with the support of a Research Grant from Worksafe Australia. The aims of this study were to measure radon levels for each season over a period of one year, at representative sites in all developed show caves around Australia, to determine yearly average radon levels for each cave tour, based on these site measurements, to estimate the radiation doses to the tour guides employed in these caves, and to identify caves with radon concentrations in excess of the action level. (authors) 7 refs., 10 tabs., 2 figs.

  6. Development of Library Processing System for Neutron Transport Calculation

    Energy Technology Data Exchange (ETDEWEB)

    Song, J. S.; Park, S. Y.; Kim, H. Y. [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)] (and others)

    2008-12-15

    A system for library generation was developed for the lattice neutron transport program for pressurized water reactor core analysis. The system extracts multi energy group nuclear data for requested nuclides from ENDF/B whose data are based on continuous energy, generates hydrogen equivalent factor and resonance integral table as functions of temperature and background cross section for resonance nuclides, generates subgroup data for the lattice program to treat resonance exactly as possible, and generates multi-group neutron library file including nuclide depletion data for use of the lattice program.

  7. Residential radon exposure and esophageal cancer. An ecological study from an area with high indoor radon concentration (Galicia, Spain).

    Science.gov (United States)

    Ruano-Ravina, Alberto; Aragonés, Nuria; Pérez-Ríos, Mónica; López-Abente, Gonzalo; Barros-Dios, Juan M

    2014-04-01

    To analyze the correlation between municipal esophageal cancer relative risk and municipal residential radon concentration in a high radon emission Spanish area. We performed an ecological study at municipal level in Galicia, Spain. For each municipality we estimated the median radon concentration and the relative risk (RR) for esophageal cancer mortality for males and females. The relative risk was calculated using a Bayesian approach. Homes with data on radon concentration were selected through stratified random sampling. To be included, each municipality had to have at least five radon measurements. We obtained Spearman's correlations for median residential radon concentration and esophageal cancer mortality RR for males and females, separately. We included 129 municipalities, covering the 79% of Galician population. 14% of municipalities had radon concentrations above the United States Environmental Protection Agency (USEPA) action level. We found a statistically significant correlation among residential radon and esophageal cancer mortality RR for males (p radon measurements the correlation pattern remained. This is the first study analyzing the association between residential radon and esophageal cancer. The results suggesting a possible effect of residential radon on esophageal cancer mortality should be explored through more robust epidemiological designs such as case-control studies.

  8. Radon levels in groundwaters and natural radioactivity in soils of the volcanic region of La Garrotxa, Spain.

    Science.gov (United States)

    Moreno, V; Bach, J; Baixeras, C; Font, Ll

    2014-02-01

    Groundwater radon level and soil radionuclide concentration have been measured in the volcanic region of La Garrotxa (Catalonia, Spain) to further research on the origin and dynamics of high radon levels over volcanic materials found in this region. Water samples from different aquifers have been collected from wells and springs and the water radon levels obtained have been lower than 30 Bq l(-1). Soil samples have been collected from different geological formations (volcanic and non-volcanic), being Quaternary sedimentary deposits those that have presented the highest mean values of (40)K, (226)Ra and (232)Th concentrations (448 ± 70 Bq kg(-1), 35 ± 5 Bq kg(-1) and 38 ± 5 Bq kg(-1), respectively). Additionally, indoor/outdoor terrestrial radiation absorbed dose rate in air have been measured to better characterize the region from the radiological point of view. Terrestrial radiation absorbed dose rates measurement points have been chosen on the basis of geological and demographical considerations and the results obtained, from 27 to 91 nGy h(-1), show a clear relation with geological formation materials. The highest terrestrial gamma absorbed dose rate is observed over Quaternary sedimentary deposits as well. All these results help to better understand previous surveys related with indoor and outdoor radon levels and to reinforce the hypotheses of a radon transport through the fissure network. Copyright © 2013 Elsevier Ltd. All rights reserved.

  9. Seasonal variation of radon level and radon effective doses in the ...

    Indian Academy of Sciences (India)

    2011-10-01

    Oct 1, 2011 ... sion factor (effective dose received by adults per unit 222Rn activity per unit of air volume),. F is the equilibrium factor of radon indoors and T is the resident time in the tomb. Hence, the annual effective dose rate E (mSv y. −1) to the public from radon and its progeny in the different sits in the Catacomb is ...

  10. Magnetosheath excursion and the relevant transport process at the magnetopause

    Directory of Open Access Journals (Sweden)

    C. L. Cai

    2009-08-01

    Full Text Available A large-amplitude excursion of the magnetosheath (MS in quiet solar wind conditions on 17 March 2004 was recorded simultaneously by the Cluster and TC-1 spacecraft. During this period, the IMF Bz was entirely northward. The coherence between the bow shock motion and magnetopause (MP motion is revealed and the excursion velocities of the bow shock motion are analyzed. In addition, the relevant plasma transport phenomenon in the form of flux fluctuations below the ion gyrofrequency at the MP is exposed and is interpreted as manifestation of the drift instability. Correlated observations on charge accumulation and electrostatic potential perturbation are recorded by electron measurements in high energy regime, and also the eventual cross-field vortex motion in the nonlinear stage and the consequential mass exchange are exhibited. The present investigation gives some new insight into the MS plasma transport mechanism across the subsolar MP region in quiet solar wind conditions during a period of northward IMF.

  11. Whole tree transportation system for timber processing depots

    Science.gov (United States)

    John Lancaster; Tom Gallagher; Tim  McDonald; Dana Mitchell

    2016-01-01

    The growing demand for alternative energy has led those who are interested in producing sustainable energy from renewable timber to devise new concepts to satisfy those demands. The concept of timber processing depots, where whole stem trees will be delivered for future processing into wood products and high quality energy fuel, has led to the re-evaluation of our...

  12. Localization of the calcium-regulated citrate transport process in proximal tubule cells.

    Science.gov (United States)

    Hering-Smith, Kathleen S; Mao, Weibo; Schiro, Faith R; Coleman-Barnett, Joycelynn; Pajor, Ana M; Hamm, L Lee

    2014-06-01

    Urinary citrate is an important inhibitor of calcium-stone formation. Most of the citrate reabsorption in the proximal tubule is thought to occur via a dicarboxylate transporter NaDC1 located in the apical membrane. OK cells, an established opossum kidney proximal tubule cell line, transport citrate but the characteristics change with extracellular calcium such that low calcium solutions stimulate total citrate transport as well as increase the apparent affinity for transport. The present studies address several fundamental properties of this novel process: the polarity of the transport process, the location of the calcium-sensitivity and whether NaDC1 is present in OK cells. OK cells grown on permeable supports exhibited apical >basolateral citrate transport. Apical transport of both citrate and succinate was sensitive to extracellular calcium whereas basolateral transport was not. Apical calcium, rather than basolateral, was the predominant determinant of changes in transport. Also 2,3-dimethylsuccinate, previously identified as an inhibitor of basolateral dicarboxylate transport, inhibited apical citrate uptake. Although the calcium-sensitive transport process in OK cells is functionally not typical NaDC1, NaDC1 is present in OK cells by Western blot and PCR. By immunolocalization studies, NaDC1 was predominantly located in discrete apical membrane or subapical areas. However, by biotinylation, apical NaDC1 decreases in the apical membrane with lowering calcium. In sum, OK cells express a calcium-sensitive/regulated dicarboxylate process at the apical membrane which responds to variations in apical calcium. Despite the functional differences of this process compared to NaDC1, NaDC1 is present in these cells, but predominantly in subapical vesicles.

  13. Groundwater chemistry and radon-222 distribution in Jerba Island, Tunisia.

    Science.gov (United States)

    Telahigue, Faten; Agoubi, Belgacem; Souid, Fayza; Kharroubi, Adel

    2018-02-01

    The present study integrates hydrogeological, hydrochemical and radiogenic data of groundwater samples taken from the Plio-Quaternary unconfined aquifer of Jerba Island, southeastern Tunisia, in order to interpret the spatial variations of the groundwater quality and identify the main hydrogeochemical factors responsible for the high ion concentrations and radon-222 content in the groundwater analysed. Thirty-nine groundwater samples were collected from open wells widespread on the island. Physical parameters (EC, pH, TDS and T °) were measured, major ions (Ca 2+ , Mg 2+ , Na + , K + , Cl - , SO 4 2- , NO 3 - and HCO 3 - ) were analysed and 222 Rn concentrations were determined using a RAD7-H 2 O. Hydrogeochemical characterisation revealed that groundwater from the Jerba aquifer has several origins. Basically, two water types exist in the island. The first one, characterized by a low to moderate salinity with a chemical facies CaMgClSO 4 , characterizes the central part of Jerba (a recharge area) due to carbonate and gypsum dissolution. The second water type with high salinities, dominated by NaKCl type, was observed in coastal areas and some parts having low topographic and piezometric levels. These areas seem to be affected by the seawater intrusion process. The 222 Rn concentrations in groundwater samples in Jerba varied from 0 Bq.L -1 to 2860 Bq.L -1 with an average of 867 Bq.L -1 . The highest values were registered in the western coastal wells and near the fault of Guellala. However, the central and eastern wells showed low radon levels. Compared to 222 Rn activity in some countries with the same lithology, radon concentrations in the Jerba unconfined aquifer have higher values influenced by the structure of the aquifer and by seawater inflow enriched with 222 Rn resulting from the decay of uranium derived from phosphogypsum deposits in the gulf of Gabes. The EC and 222 Rn spatial variability in the study area were mapped using ARC Map 10.3 software

  14. A new productivity function and stability criterion in chemical vapor transport processes

    NARCIS (Netherlands)

    Klosse, K.

    1975-01-01

    The crystal growth rate in a chemical vapor transport process using a closed system is analyzed on the basis of a one-dimensional configuration. A simplified model of vapor transport enables one to obtain a set of equations yielding the rates of reaction without a complete evaluation of the partial

  15. Production and cost of harvesting, processing, and transporting small-diameter (energy

    Science.gov (United States)

    Fei Pan; Han-Sup Han; Leonard R. Johnson; William J. Elliot

    2008-01-01

    Dense, small-diameter stands generally require thinning from below to improve fire-tolerance. The resulting forest biomass can be used for energy production. The cost of harvesting, processing, and transporting small-diameter trees often exceeds revenues due to high costs associated with harvesting and transportation and low market values for forest biomass....

  16. Protect Your Home and Family from Radon

    Science.gov (United States)

    DALLAS - (Jan. 11, 2016) Radon-the silent killer-is responsible for about 21,000 lung cancer deaths every year. The U.S. Environmental Protection Agency encourages Americans around the country to test their homes for this naturally occurring radioac

  17. Radon concentrations in a spa in Serbia.

    Science.gov (United States)

    Manic, G; Petrovic, S; Vesna, Manic; Popovic, Dragana; Todorovic, Dragana

    2006-05-01

    The paper presents the results of indoor radon concentration survey in 201 homes and offices in Niska Banja (the Spa of Nis), a well-known health resort and a spa in the South-East of Serbia. Radon indoor concentrations were determined by active charcoal method, according to standard EPA procedure. The indoor radon concentrations were in the range of up to 200 Bq/m(3) (47%), from 200-600 Bq/m(3) (26%) and over 600 Bq/m(3) (27%). Three areas of extremely high average radon concentrations were found (1,340-4,340 Bq/m(3)), with a maximum above 13,000 Bq/m(3). The content of natural radionuclides ((226)Ra, (214)Pb, (214)Bi, (235)U, (228)Ac, (212)Pb, (212)Bi, (208)Tl, (40)K) and (137)Cs, as well as the content of total uranium, thorium and potassium in mud used in peloidotherapy in the Health Institute "Niska Banja" was determined, too. The activities of the radionuclides were determined on an HPGe detector, by standard gamma spectroscopy. The results indicated considerably high amounts of total uranium and thorium (0.021 g/kg mud and 0.003 g/kg mud, respectively), due to the karsts origin of the soil.

  18. RADON REDUCTION IN A CRAWL SPACE HOUSE

    Science.gov (United States)

    Radon, a naturally occurring radioactive gas, is drawn from the soil into a house when low air pressure exists in the house. This is a commonplace environmental hazard in the United States, Canada, and northern Europe. The U.S. Environmental Protection Agency (EPA) is developing ...

  19. Radon activity measurements around Bakreswar thermal springs

    Energy Technology Data Exchange (ETDEWEB)

    Chaudhuri, Hirok [Saha Institute of Nuclear Physics, 1/AF Bidhannagar, Kolkata, West Bengal 700 064 (India); Das, Nisith K., E-mail: nkdas@veccal.ernet.i [Variable Energy Cyclotron Centre, Atomic Energy, 1/AF Bidhannagar, Kolkata, West Bengal 700 064 (India); Bhandari, Rakesh K. [Variable Energy Cyclotron Centre, Atomic Energy, 1/AF Bidhannagar, Kolkata, West Bengal 700 064 (India); Sen, Prasanta [Saha Institute of Nuclear Physics, 1/AF Bidhannagar, Kolkata, West Bengal 700 064 (India); Sinha, Bikash [Variable Energy Cyclotron Centre, Atomic Energy, 1/AF Bidhannagar, Kolkata, West Bengal 700 064 (India)

    2010-01-15

    {sup 222}Rn concentrations were measured in the bubble gases, spring waters, soil gases and in ambient air around the thermal springs at Bakreswar in West Bengal, India. This group of springs lies within a geothermal zone having exceptionally high heat flow about 230 mW/m{sup 2}, resembling young oceanic ridges. The spring gas has a high radon activity (approx885 kBq/m{sup 3}) and is rich in helium (approx1.4 vol. %) with appreciably large flow rate. The measured radon exhalation rates in the soils of the spring area show extensive variations from 831 to 4550/mBqm{sup 2} h while {sup 222}Rn concentrations in the different spring waters vary from 3.18 to 46.9 kBq/m{sup 3}. Surface air at a radius of 40 m around the springs, within which is situated the Bakreswar temple complex and a group of dwellings, has radon concentration between 450 and 500 Bq/m{sup 3}. In the present paper we assess the radon activity background in and around the spring area due to the different contributing sources and its possible effect on visiting pilgrims and the people who reside close to the springs.

  20. Optimizing laboratory-based radon flux measurements for sediments.

    Science.gov (United States)

    Chanyotha, Supitcha; Kranrod, Chutima; Kritsananuwat, Rawiwan; Lane-Smith, Derek; Burnett, William C

    2016-07-01

    Radon flux via diffusion from sediments and other materials may be determined in the laboratory by circulating air through the sample and a radon detector in a closed loop. However, this approach is complicated by the necessity of having to determine the total air volume in the system and accounting for any small air leaks that can arise if using extended measurement periods. We designed a simple open-loop configuration that includes a measured mass of wet sediment and water inside a gas-tight reaction flask connected to a drying system and a radon-in-air analyzer. Ambient air flows through two charcoal columns before entering the reaction vessel to eliminate incoming radon. After traveling through the reaction flask, the air passes the drier and the radon analyzer and is then vented. After some time, the radon activity will reach a steady state depending upon the airflow rate. With this approach, the radon flux via diffusion is simply the product of the steady-state radon activity (Bq/m(3)) multiplied by the airflow rate (mL/min). We demonstrated that this setup could produce good results for materials that produce relatively high radon fluxes. We also show that a modified closed system approach, including radon removal of the incoming air by charcoal filtration in a bypass, can produce very good results including samples with very low emission rates. Copyright © 2016 Elsevier Ltd. All rights reserved.

  1. Application of nuclear track detectors for radon related measurments

    Energy Technology Data Exchange (ETDEWEB)

    Abu-Jarad, F.A. (King Fahd Univ. of Petroleum and Minerals, Dhahran (Saudi Arabia). Energy Resources Div.)

    1988-01-01

    The application of nuclear track detectors for radon related measurements is discussed. The ''Can Technique'', used for measuring radon emanation from building materials, walls and soil; the ''Working Level Monitor'', used for measuring short period working levels of radon daughters in houses; and ''Passive Radon Dosimeters'', used to measure radon levels in houses for long term (few months) periods are described. Application of nuclear track detectors for measuring the radon daughters plate-out on the surface of mixing fan blades and walls are discussed. The uranium content of some wall papers was found to be 6 ppm. The variation of radon progeny concentration in the same room was measured and supported by another study through Gas Chromatograph measurements. The independence of radon concentration on room level in high-rise buildings was established. The effect of sub-floor radon emanation on radon concentration in houses is dependent on whether there is sub-floor ventilation or not. (author).

  2. Modelling of transport and biogeochemical processes in pollution plumes: Literature review of model development

    DEFF Research Database (Denmark)

    Brun, A.; Engesgaard, Peter Knudegaard

    2002-01-01

    A literature survey shows how biogeochemical (coupled organic and inorganic reaction processes) transport models are based on considering the complete biodegradation process as either a single- or as a two-step process. It is demonstrated that some two-step process models rely on the Partial Equi....... A second paper [J. Hydrol. 256 (2002) 230-249], reports the application of the model to a field study of biogeochemical transport processes in a landfill plume in Denmark (Vejen). (C) 2002 Elsevier Science B.V. All rights reserved....

  3. Magnetic Processing of Structural Components for Transportation Vehicles

    Energy Technology Data Exchange (ETDEWEB)

    Mackiewicz-Ludtka, G.; Ludtka, G. M.; Fleming, S. [Metalsa Roanoke, Inc.; del Prado Villasana, J. [Metalsa Roanoke, Inc.

    2011-09-30

    The specific goal of this project was to develop and evaluate the effect of magnetic processing as a viable and new technology to manufacture side‐rails for heavy trucks; and to demonstrate the applicability of this technology for an industrial truck/automotive process. The targeted performance enhancements for this project were to increase the hardness or strength of two families of alloys (comparable carbon contents but one alloy system incorporating hardenability improving additions of titanium and boron) by 15 to 20%. Thermomagnetic processing has been shown to make significant and unprecedented, simultaneous improvements in yield strength and ultimate tensile strength with no loss of ductility for the truck rail application investigated in this project. Improvements in the ultimate tensile strength and yield strength in the range 20 to 30% have been measured even for the lower hardenability alloy samples that only received a very low magnetic field tempering treatment at a tempering temperature that was 67% lower than the current non-magnetic field enhanced commercial process and for a brief tempering time of 20% of the time required in their current process at the higher temperature. These significant developments, that require further demonstration and investigation on current commercial and other alloy systems, promise the evolution of a much more energy efficient and lower-carbon footprint process to be used in the future to produce stronger, tougher, and lighter weight truck rails. The property increases in the truck rails themselves will enable lighter weight truck side-rails to be produced which will reduce the overall weight of heavy duty trucks which will reduce fuel consumption and be an enabler of the goals of the DOE EERE SuperTruck Program where fuel consumption reductions of 50% are targeted for the future generation of trucks.

  4. Activity measurements of radon from construction materials.

    Science.gov (United States)

    Fior, L; Nicolosi Corrêa, J; Paschuk, S A; Denyak, V V; Schelin, H R; Soreanu Pecequilo, B R; Kappke, J

    2012-07-01

    This work presents the results of radon concentration measurements of construction materials used in the Brazilian industry, such as clay (red) bricks and concrete blocks. The measurements focused on the detection of indoor radon activity during different construction stages and the analysis of radionuclides present in the construction materials. For this purpose, sealed chambers with internal dimensions of approximately 60×60×60 cm3 were built within a protected and isolated laboratory environment, and stable air humidity and temperature levels were maintained. These chambers were also used for radon emanation reduction tests. The chambers were built in four major stages: (1) assembly of the walls using clay (red) bricks, concrete blocks, and mortar; (2) installation of plaster; (3) finishing of wall surface using lime; and (4) insulation of wall surface and finishing using paint. Radon measurements were performed using polycarbonate etched track detectors. By comparing the three layers applied to the masonry walls, it was concluded that only the last step (wall painting using acrylic varnish) reduced the radon emanation, by a factor of approximately 2. Samples of the construction materials (clay bricks and concrete blocks) were ground, homogenized, and subjected to gamma-ray spectrometry analysis to evaluate the activity concentrations of 226Ra, 232Th and 40K. The values for the index of the activity concentration (I), radium equivalent activity (Raeq), and external hazard index (Hext) showed that these construction materials could be used without restrictions or concern about the equivalent dose limit (1 mSv/year). Copyright © 2011 Elsevier Ltd. All rights reserved.

  5. Formation of the Cycle of Business Processes of Management of Marketing Activity of a Transport Enterprise

    Directory of Open Access Journals (Sweden)

    Horielov Dmytro O.

    2014-02-01

    Full Text Available The article is devoted to problems of organisation of the process of management of marketing activity of an enterprise. It specifies the model of services of a transport enterprise and provides levels of services and their structure: basic, real, expanded, expected and prospective. The article offers to differentiate planning and realisation of the transportation service by its levels, each of which would correspond with a separate business process of management. It reveals specific features of use of instruments of the traditional, internal and interactive marketing in the market of transportation services. It identifies the structure of the object when managing marketing activity of a transportation enterprise. The article uses the Deming cycle to formulate general principles of formation of business processes of management of marketing activity: “Motivation – Plan – Do – Check – Act”. The proposed cycle would ensure continuous improvement of the said business processes of an enterprise in accordance with international quality standards (ISO.

  6. An evaluation of Mexican transportation planning, finance, implementation, and construction processes.

    Science.gov (United States)

    2009-10-01

    This research examined the legal, financial, institutional and policy processes that Mexico uses to plan, finance, : construct, and implement its transportation network. It documents through twelve case studies the state of the : practice in planning...

  7. Use of 1 H NMR to study transport processes in porous biosystems

    NARCIS (Netherlands)

    As, van H.; Lens, P.N.L.

    2001-01-01

    The operation of bioreactors and the metabolism of microorganisms in biofilms or soil/sediment systems are strongly dictated by the transport processes therein. Nuclear magnetic resonance (NMR) spectroscopy or magnetic resonance imaging (MRI) allow nondestructive and noninvasive quantification and

  8. Research on autonomous identification of airport targets based on Gabor filtering and Radon transform

    Science.gov (United States)

    Yi, Juan; Du, Qingyu; Zhang, Hong jiang; Zhang, Yao lei

    2017-11-01

    Target recognition is a leading key technology in intelligent image processing and application development at present, with the enhancement of computer processing ability, autonomous target recognition algorithm, gradually improve intelligence, and showed good adaptability. Taking the airport target as the research object, analysis the airport layout characteristics, construction of knowledge model, Gabor filter and Radon transform based on the target recognition algorithm of independent design, image processing and feature extraction of the airport, the algorithm was verified, and achieved better recognition results.

  9. Evaluation of Transportation Vibration Associated with Relocation of Work in Process As Part of KCRIMS

    Energy Technology Data Exchange (ETDEWEB)

    Hartwig, Troy

    2013-04-01

    During relocation of the Kansas City Plant (KCP) from the site at Bannister Road to the site at Botts Road, work in process (WIP) within a production department must be transported. This report recommends packaging to mitigate vibration levels experienced by products during between-facility transportation. Measurements and analysis demonstrate that this mitigation results in vibration levels less than those experienced by the product during routine production processes within potentially damaging frequency ranges.

  10. Using {sup 222}Rn as a tracer of geodynamical processes in underground environments

    Energy Technology Data Exchange (ETDEWEB)

    Valladares, D.L. [GEA, Instituto de Matemática Aplicada San Luis (IMASL), Universidad Nacional de San Luis, Consejo Nacional de Investigaciones Científicas y Técnicas, Ej. de los Andes 950, D5700HHW San Luis (Argentina); Silva, A.A.R. da [Instituto de Física, Universidade de São Paulo, P.O.Box 66318, 05314-970, São Paulo, SP (Brazil); Serviço Especializado em Engenharia de Segurança e Medicina do Trabalho, Departamento de Saúde, Universidade de São Paulo, Rua da Reitoria, 109, 05508-900, São Paulo, SP (Brazil); Lacerda, T. [Instituto de Física, Universidade Federal Fluminense, Av. Gal Milton Tavares de Souza, s/n" o, Gragoatá, 24210-340, Niterói, RJ (Brazil); Anjos, R.M., E-mail: meigikos@if.uff.br [Instituto de Física, Universidade Federal Fluminense, Av. Gal Milton Tavares de Souza, s/n" o, Gragoatá, 24210-340, Niterói, RJ (Brazil); Rizzotto, M.; Velasco, H.; Rosas, J.P. de [GEA, Instituto de Matemática Aplicada San Luis (IMASL), Universidad Nacional de San Luis, Consejo Nacional de Investigaciones Científicas y Técnicas, Ej. de los Andes 950, D5700HHW San Luis (Argentina); Tognelli, G. [Departamento de Geología, Universidad Nacional de San Luis, Ej. de los Andes 950, D5700HHW San Luis (Argentina); and others

    2014-01-01

    Radon levels in two old mines in San Luis, Argentina, were measured and analyzed, with the aim to assess the potential use of this radioactive noble gas as a tracer of geological processes in underground environments. La Carolina gold mine and Los Cóndores tungsten mine are today used as tourism mines. CR-39 nuclear track detectors were used for this purpose. Measurements were performed during both winter and summer seasons. The findings show that in these environments, significant radon concentrations are subject to large seasonal fluctuations, due to the strong dependence on natural ventilation with the outside temperature variations. For both mines, higher concentration values of {sup 222}Rn were observed in summer than in winter; with an extreme ratio of 2.5 times between summer and winter seasons for Los Cóndores mine. The pattern of radon transport inside La Carolina mine revealed, contrary to what was believed, that this mine behaves as a system with two entrances located at different levels. However, this feature can only be observed in the winter season, when there is a marked difference between the inside and outside temperatures of the mine. In the case of Los Cóndores mine, the radon concentration pattern distribution is principally established by air current due to chimney-effect in summer and winter seasons. In both cases, the analyses of radon pattern distribution appear as a good method to trace air currents, and then localize unknown ducts, fissures or secondary tunnels in subterranean environments. - Highlights: • {sup 222}Rn levels in two old mines in San Luis, Argentina • CR-39 nuclear track detectors were used for this purpose • higher concentration values of {sup 222}Rn were observed in summer than in winter • radon pattern distribution appear as a good method to trace air currents • it localizes unknown ducts, fissures or secondary tunnels in subterranean environments.

  11. Laminar flow and convective transport processes scaling principles and asymptotic analysis

    CERN Document Server

    Brenner, Howard

    1992-01-01

    Laminar Flow and Convective Transport Processes: Scaling Principles and Asymptotic Analysis presents analytic methods for the solution of fluid mechanics and convective transport processes, all in the laminar flow regime. This book brings together the results of almost 30 years of research on the use of nondimensionalization, scaling principles, and asymptotic analysis into a comprehensive form suitable for presentation in a core graduate-level course on fluid mechanics and the convective transport of heat. A considerable amount of material on viscous-dominated flows is covered.A unique feat

  12. Elastic collisions and related transport processes in cold hydrogen plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Krstic, Predrag S.; Schultz, David R. [Oak Ridge National Lab., Physics Division, Oak Ridge, TN (United States)

    2000-01-01

    Owing to the critical role played by elastic processes in thermal power exhaust in the divertor region of fusion plasmas as well as in other gas/plasma environments and to its fundamental nature, we have performed extensive, highly accurate, fully quantal calculations of differential and integral cross sections for elastic, charge transfer, spin exchange, and vibrational excitation in slow collisions (0.1-100 eV) among isotopic variants of H{sup +}, H, H{sub 2} and He. (author)

  13. A search profile for dwellings with elevated radon levels

    DEFF Research Database (Denmark)

    Damkjær, A.; Andersen, C.E.; Majborn, B.

    1996-01-01

    A search profile for dwellings with elevated radon levels has been employed to investigate possibly radon-prone areas in Denmark and to find houses suitable for radon mitigation studies. The profile is defined as dwellings which are single-family houses with slab-on-grade foundation or partly...... basement/slab-on-grade foundation built on either fractured granitic basement rocks, or fractured limestone. Clayey till areas were also included in the profile in order to confirm earlier findings. Three areas representing these surface geologies were selected for indoor radon measurements with CR-39...... track detectors, and a total of 200 houses matching the profile underwent radon measurements during the winter 1994-95. The distribution of the measured radon concentrations were found in most cases to comply with log-normal distributions. Measurements in the living rooms of houses in each of the three...

  14. Identification of sources of high radon levels in Slovenian schools.

    Science.gov (United States)

    Vaupotic, J

    2002-01-01

    The sources of radon were investigated in twenty selected schools with high room levels of radiation. A combination of radon measuring techniques was applied: etched track and electret detectors to obtain average indoor air radon concentration. devices to record radon concentration continuously and thus characterise its diurnal variation, and alpha scintillation cells to analyse air from potential sources of radon entry. In some cases, a single strong source was identified (e.g. sinks, sub-floor channels), while in others the poor quality of the basic concrete slab was responsible for high indoor radon concentrations. The combination of etched track and electret detectors and alpha scintillation cells was essential for locating these sources.

  15. Measuring radon in soil gas and groundwaters: a review

    Directory of Open Access Journals (Sweden)

    C. Papastefanou

    2007-06-01

    Full Text Available Instruments for the measurements of radon and its decay products in earthquake research are based mostly on the detection of alpha particles. The devices and methods used depend on whether the techniques measure radon or radon decay products, and the duration of the measurements, of which there are three types: i grab or instantaneous, ii integrating and iii continuous. Other criteria used in the design of these instruments are field measurements applicability, portability, convenience and reliability. With the recent increased demand for radon and radon decay products measurements, instruments development has focused on the design of appropriate devices for short-term measurements, as well as on more complex and sophisticated instruments for long-term measurements used in radon research for geophysical, geochemical and hydrological studies.

  16. Ambient Radon-222 Monitoring in Amargosa Valley, Nevada

    Energy Technology Data Exchange (ETDEWEB)

    L.H. Karr; J.J. Tappen; D. Shafer; K.J. Gray

    2008-06-05

    As part of a program to characterize and baseline selected environmental parameters in the region around the proposed repository at Yucca Mountain, Nevada, ambient radon-222 monitoring was conducted in the rural community of Amargosa Valley, the community closest to the proposed repository site. Passive integrating radon monitors and a continuous radon monitoring instrument were deployed adjacent to the Community Environmental Monitoring Program (CEMP) (http://www.cemp.dri.edu/index.html) station located in the Amargosa Valley Community Center near the library. The CEMP station provided real-time ambient gamma exposure and meteorological data used to correct the integrated radon measurements as well as verify meteorological data collected by the continuous radon monitoring instrument. Additionally, different types of environmental enclosures that housed the monitors and instrument were used to determine if particular designs influenced the ambient radon measurements.

  17. Design Criteria for Achieving Low Radon Concentration Indoors

    DEFF Research Database (Denmark)

    Rasmussen, Torben Valdbjørn

    2016-01-01

    Design criteria for achieving low radon concentration indoors are presented in this paper. The paper suggests three design criteria. These criteria have to be considered at the early stage of the building design phase to meet the latest recommendations from the World Health Organization in most...... the radon concentration in the indoor air. In addition, a cheap and reliable method for measuring the radon concentration in the air indoors is described. The provision on radon in the Danish Building Regulations complies with the latest recommendations from the World Health Organization. Radon can cause...... lung cancer and it is not known whether there is a lower limit for when it is not harmful to human beings. Therefore, it is important to reduce the radon concentration as much as possible indoors in buildings. Airtightness is an important factor when dealing with buildings. For the building envelope...

  18. Etched track radiometers in radon measurements: a review

    CERN Document Server

    Nikolaev, V A

    1999-01-01

    Passive radon radiometers, based on alpha particle etched track detectors, are very attractive for the assessment of radon exposure. The present review considers various devices used for measurement of the volume activity of radon isotopes and their daughters and determination of equilibrium coefficients. Such devices can be classified into 8 groups: (i) open or 'bare' detectors, (ii) open chambers, (iii) sup 2 sup 2 sup 2 Rn chambers with an inlet filter, (iv) advanced sup 2 sup 2 sup 2 Rn radiometers, (v) multipurpose radiometers, (vi) radiometers based on a combination of etched track detectors and an electrostatic field, (vii) radiometers based on etched track detectors and activated charcoal and (viii) devices for the measurement of radon isotopes and/or radon daughters by means of track parameter measurements. Some of them such as the open detector and the chamber with an inlet filter have a variety of modifications and are applied widely both in geophysical research and radon dosimetric surveys. At the...

  19. The transfer of radon from potable water into house air

    Energy Technology Data Exchange (ETDEWEB)

    Hess, C.T.; Vietti, M.A.; Lachapelle, E.B.; Guillemette, J.F. (Univ. of Maine, Orono (USA))

    1988-09-01

    There have been very few comparisons of the radon in air due to use of potable water containing radon. To better determine the health risk due to radon in water in homes, 40 houses in southern and central Maine were measured for house characteristics such as building materials, volume and air exchange rate and for radon in water and air. The houses were all wood with basements and have wood, oil and solar heat. To increase the radon due to water use, a two hour water burst was used to simulate 24 hours of water use for the occupants. The water use was monitored along with the radon concentration in air for ten minute intervals.

  20. Deformational mass transport and invasive processes in soil evolution

    Science.gov (United States)

    Brimhall, George H.; Chadwick, Oliver A.; Lewis, Chris J.; Compston, William; Williams, Ian S.; Danti, Kathy J.; Dietrich, William E.; Power, Mary E.; Hendricks, David; Bratt, James

    1992-01-01

    Channels left in soil by decayed roots and burrowing animals allow organic and inorganic precipitates and detritus to move through soil from above, to depths at which the minuteness of pores restricts further passage. Consecutive translocation-and-root-growth phases stir the soil, constituting an invasive, dilatational process which generates cumulative strains. Below the depths thus affected, mineral dissolution by descending organic acids leads to internal collapse; this softened/condensed precursor horizon is then transformed into soil via biological activity that mixes and expands the evolving residuum through root and micropore-network invasion.

  1. Influence of the meteorological spatial resolution on Radon-222 backward modelling with FLEXPART

    Science.gov (United States)

    Arnold, D.; Seibert, P.; Vargas, A.

    2009-04-01

    One of the main important origins of uncertainties in atmospheric transport modelling comes from the meteorological input fields. Currently, operational analysis from the ECMWF, one of the reference sources of meteorological inputs used for modelling, are provided with horizontal spatial resolutions from 2 degrees down to 0.2 degrees, and also with different vertical and temporal resolutions. In this work it has been studied how the increase in spatial resolution of the ECMWF fields would affect the dispersion calculations of Radon-222. Backward modelling has been done with the widely used Lagrangian particle dispersion model FLEXPARTv6.2.Simulated radon concentration time series were compared with measurements at a station located in the outskirts of Barcelona (Spain). Results show relevant differences and better agreement is achieved when using the highest resolution fields. This study shows that if good model performance is desired, it is advisable to use ECMWF with 0.2 deg resolution despite the increase in computational dema

  2. Impact of fluoride and other aquatic parameters on radon concentration in natural waters

    Energy Technology Data Exchange (ETDEWEB)

    Salih, Isam; Baeckstroem, Mattias; Karlsson, Stefan; Lund, Eva; Pettersson, H.B.L. E-mail: hakan.pettersson@lio.se

    2004-01-01

    Radon ({sup 222}Rn) accumulation in water in relation to stable elements was studied for the purpose of determining factors influencing the transfer of {sup 222}Rn to and from water. In 72 groundwater samples, {sup 222}Rn and about 70 analytical parameters were analysed using radiometric and ICP-MS techniques. Using multivariate statistics (partial least squares), it was observed that {sup 222}Rn has a positive correlation with fluoride and uranium. The correlation with fluoride was further investigated by a laboratory time-scale experiment to measure the emanation of {sup 222}Rn from water as a function of fluoride, pH and carbonate. The transfer of {sup 222}Rn from water was measured by continuous monitoring in air in a closed loop set-up. It was observed that fluoride in water adhere or trap {sup 222}Rn preferably in acidic water (pH 3). It is suspected that natural physical processes (such as diffusion and microbubble phenomenon) are less effective to transport {sup 222}Rn in the presence of fluoride.

  3. Radon Assessment of Occupational Facilities, Homestead ARB, FL

    Science.gov (United States)

    2013-11-21

    Consultative Letter 3. DATES COVERED (From – To) May 2013 – August 2013 4. TITLE AND SUBTITLE Radon Assessment of Occupational Facilities...unlimited. Case Number: 88ABW-2013-4919, 21 Nov 2013 13. SUPPLEMENTARY NOTES 14. ABSTRACT An assessment of indoor radon concentrations was...established in AFI 48-148 for long-term monitoring. Historical results indicate a radon risk characterization category of “medium,” requiring all

  4. Indoor radon measurements in the city of Valencia.

    Science.gov (United States)

    Tondeur, F; Ródenas, J; Querol, A; Ortiz, J; Juste, B

    2011-08-01

    The indoor radon risk in Valencia (Spain) was studied more than twenty years ago in two surveys using different methodologies and leading to contradictory results. We report here on new indoor radon measurements with the charcoal canister technique, which confirm the low average level of indoor radon in the city, with a geometrical mean of 24 Bq/m(3) and an arithmetic mean of 27 Bq/m(3). 2010 Elsevier Ltd. All rights reserved.

  5. A self-calibrating radon monitor with statistical discrimination

    CERN Document Server

    Valcov, N

    2002-01-01

    A radon monitor, able to perform the measurement of the radon and its progeny volumic activity, in a gamma-ray or natural radiation background field, was developed. The instrument consists of a 10 l ionization chamber, a high voltage source, an integrating preamplifier, a data acquisition system and a personal computer. A new method for self-calibration of Radon volumic activity measurements, based on the alpha counting with an ionization chamber is also presented.

  6. Application of pylon radon daughter standard for calibration of radiometers.

    Science.gov (United States)

    Chruścielewski, Wojciech; Olszewski, Jerzy; Bogusz, Malgorzata

    2002-01-01

    Radiometers for measurements of radon daughter potential energy used in the surveillance of the work environment need a systematic calibration. This paper presents how a commercially available device produced by the Pylon Company can be applied. This device allows to produce, simply and directly, standard sources of radon daughters, corresponding with the energy, geometry and properties of radiation originated from an air sample. The calibration yielded the results that proved to be in agreement with those obtained previously by means of radon chamber.

  7. Radon mapping in south Tyrol: comparison between two different procedures.

    Science.gov (United States)

    Verdi, L; Caldognetto, E; Trotti, F

    2004-01-01

    In this paper two different procedures for radon mapping have been compared on the same database referring to indoor radon records of South Tyrol. The first procedure is based on descriptive statistics applied to administrative units while the second one implies a more complicated statistical analysis applied to a regular grid: it involves floor level normalization of radon data, filling and smoothing algorithms for the territory cells.

  8. Correction factors for determination of annual average radon concentration in dwellings of Poland resulting from seasonal variability of indoor radon

    Energy Technology Data Exchange (ETDEWEB)

    Kozak, K., E-mail: Krzysztof.Kozak@ifj.edu.pl [Institute of Nuclear Physics PAN, Radzikowskiego 152, 31-342 Krakow (Poland); Mazur, J. [Institute of Nuclear Physics PAN, Radzikowskiego 152, 31-342 Krakow (Poland); KozLowska, B. [University of Silesia, Bankowa 12, 40-007 Katowice (Poland); Karpinska, M. [Medical University of Bialystok, Jana Kilinskiego 1, 15-089 BiaLystok (Poland); Przylibski, T.A. [WrocLaw University of Technology, Wybrzeze S. Wyspianskiego 27, 50-370 WrocLaw (Poland); Mamont-Ciesla, K. [Central Laboratory for Radiological Protection, Konwaliowa 7, 03-194 Warszawa (Poland); Grzadziel, D. [Institute of Nuclear Physics PAN, Radzikowskiego 152, 31-342 Krakow (Poland); Stawarz, O. [Central Laboratory for Radiological Protection, Konwaliowa 7, 03-194 Warszawa (Poland); Wysocka, M. [Central Mining Institute, Plac Gwarkow1, 40-166 Katowice (Poland); Dorda, J. [University of Silesia, Bankowa 12, 40-007 Katowice (Poland); Zebrowski, A. [WrocLaw University of Technology, Wybrzeze S. Wyspianskiego 27, 50-370 WrocLaw (Poland); Olszewski, J. [Nofer Institute of Occupational Medicine, Sw.Teresy od Dzieciatka Jezus 8, 91-348 lodz (Poland); Hovhannisyan, H. [Institute of Nuclear Physics PAN, Radzikowskiego 152, 31-342 Krakow (Poland); Dohojda, M. [Institute of Building Technology (ITB), Filtrowa 1, 00-611 Warszawa (Poland); KapaLa, J. [Medical University of Bialystok, Jana Kilinskiego 1, 15-089 BiaLystok (Poland); Chmielewska, I. [Central Mining Institute, Plac Gwarkow1, 40-166 Katowice (Poland); KLos, B. [University of Silesia, Bankowa 12, 40-007 Katowice (Poland); Jankowski, J. [Nofer Institute of Occupational Medicine, Sw.Teresy od Dzieciatka Jezus 8, 91-348 lodz (Poland); Mnich, S. [Medical University of Bialystok, Jana Kilinskiego 1, 15-089 BiaLystok (Poland); KoLodziej, R. [Central Mining Institute, Plac Gwarkow1, 40-166 Katowice (Poland)

    2011-10-15

    The method for the calculation of correction factors is presented, which can be used for the assessment of the mean annual radon concentration on the basis of 1-month or 3-month indoor measurements. Annual radon concentration is an essential value for the determination of the annual dose due to radon inhalation. The measurements have been carried out in 132 houses in Poland over a period of one year. The passive method of track detectors with CR-39 foil was applied. Four thermal-precipitation regions in Poland were established and correction factors were calculated for each region, separately for houses with and without basements. - Highlights: > Using radon concentration results in houses we calculated the correction factors. > Factors were calculated for each month, 2 house types in different regions in Poland. > They enable the evaluation of average annual radon concentration in the house. > Annual average radon concentration basing on 1 or 3 months detector exposure.

  9. Traceability of radon-222 activity concentration in the radon chamber at the technical university of Catalonia (Spain)

    Science.gov (United States)

    Vargas, A.; Ortega, X.; Martín Matarranz, J. L.

    2004-07-01

    In order to provide reference 222Rn activity concentration, a device based on the alpha spectrometric measurement of 218Po collected electrostatically on a PIPS detector, has been developed and characterised. Traceability is achieved by the use of primary 222Rn standard activity inside a glass bulb obtained from the Physikalisch-Technische Bundesanstalt. Radon standard activity is then transferred to the instrument that measures the reference radon activity concentration. The instrument is used in the walk-in radon chamber of the Institute of Energy Technology at the Technical University of Catalonia in order to provide a reference atmosphere for the calibration of radon concentration detectors. Under typical environmental calibration conditions within the radon chamber, an expanded uncertainty of roughly 4% ( k=2) for radon concentration is usually estimated.

  10. Toward resolving model-measurement discrepancies of radon entry into houses

    Energy Technology Data Exchange (ETDEWEB)

    Garbesi, Karina [Univ. of California, Berkeley, CA (United States). Energy and Resources Group

    1994-10-01

    Analysis of the literature indicated that radon transport models significantly and consistently underpredict the advective entry into houses of soil-gas borne radon. Advective entry is the dominant mechanism resulting in high concentrations of radon indoors. The author investigated the source of the model-measurement discrepancy via carefully controlled field experiments conducted at an experimental basement located in natural soil in Ben Lomond, California. Early experiments at the structure confirmed the existence and magnitude of the model-measurement discrepancy, ensuring that it was not merely an artifact of inherently complex and poorly understood field sites. The measured soil-gas entry rate during structure depressurization was found to be an order of magnitude larger than predicted by a current three-dimensional numerical model of radon transport. The exact magnitude of the discrepancy depends on whether the arithmetic or geometric mean of the small-scale measurements of permeability is used to estimate the effective permeability of the soil. This factor is a critical empirical input to the model and was determined for the Ben Lomond site in the typical fashion using single-probe static depressurization measurements at multiple locations. The remainder of the dissertation research tests a hypothesis to explain the observed discrepancy: that soil permeability assessed using relatively small-scale probe measurements does not reflect bulk soil permeability for flows that is likely to occur at larger scales of several meters or more in real houses and in the test structure. The idea is that soil heterogeneity is of a nature that, as flows occur over larger scales, larger scales of heterogeneity are encountered that facilitate larger flux rates, resulting in a scale dependence of effective soil permeability.

  11. Current international intercomparison measurement on radon and its progeny

    Energy Technology Data Exchange (ETDEWEB)

    Yamasaki, Keizo [Kyoto Univ., Kumatori, Osaka (Japan). Research Reactor Inst.

    1996-12-01

    The international intercomparison measurement on radon and its progeny was held between the EML of USDOE and several Japanese organisations, using the radon test chamber installed in EML. Japanese results of radon concentration by the active method using the ionization chamber or scintillation cell and the passive method using the solid track detector were about 5% small compared to that of EML. On the results of radon progeny, there were not any large systematic differences between EML and Japanese participants in spite of wide range of deviation except for the results at the condition of low aerosol density. (author)

  12. Management of radon: a review of ICRP recommendations.

    Science.gov (United States)

    Vaillant, Ludovic; Bataille, Céline

    2012-09-01

    This article proposes a review of past and current ICRP publications dealing with the management of radon exposures. Its main objective is to identify and discuss the driving factors that have been used by the Commission during the last 50 years so as to better appreciate current issues regarding radon exposure management. The analysis shows that major evolutions took place in very recent years. As far as the management of radon exposures is concerned, ICRP recommended, until ICRP Publication 103 (ICRP 2007 ICRP Publication 103; Ann. ICRP 37), to use action levels and to consider only exposures above these levels. The Commission has reviewed its approach and now proposes to manage any radon exposure through the application of the optimisation principle and associated reference levels. As far as the assessment of the radon risk is concerned, it appears that the successive changes made by ICRP did not have a strong impact on the values of radon gas concentration recommended as action levels either in dwellings or in workplaces. The major change occurred in late 2009 with the publication of the ICRP Statement on Radon, which acknowledged that the radon risk has been underestimated by a factor of 2, thus inducing a major revision of radon reference levels.

  13. Effect of internal wall covers on radon emanation inside houses

    Energy Technology Data Exchange (ETDEWEB)

    Abu-Jarad, F.; Fremlin, J.H.

    1983-03-01

    Most types of paint for the internal walls of houses will reduce radon emanation from building materials. At the same time, the effect of paint will increase the concentration of radon inside the material itself and will increase the radon emanation from unpainted areas. One type of wall paper contains 6 and 0.3 ppm of uranium in its decorated and undecorated surfaces, respectively, the colouring being the main source of uranium. Other wallpapers appear to be free from uranium. Wallpaper, gypsum and plaster may increase the radon activity inside houses depending on their radium contents.

  14. Nonlinear Radon Transform Using Zernike Moment for Shape Analysis

    Directory of Open Access Journals (Sweden)

    Ziping Ma

    2013-01-01

    Full Text Available We extend the linear Radon transform to a nonlinear space and propose a method by applying the nonlinear Radon transform to Zernike moments to extract shape descriptors. These descriptors are obtained by computing Zernike moment on the radial and angular coordinates of the pattern image's nonlinear Radon matrix. Theoretical and experimental results validate the effectiveness and the robustness of the method. The experimental results show the performance of the proposed method in the case of nonlinear space equals or outperforms that in the case of linear Radon.

  15. Radon control systems in existing and new construction: a review.

    Science.gov (United States)

    Rahman, Naureen Mahbub; Tracy, Bliss L

    2009-08-01

    In support of the implementation of the new Canadian radon guideline, a comprehensive review of radon mitigation techniques used in countries around the world was undertaken, with particular emphasis on North America and Europe that have climates and construction techniques similar to Canada. The results of this review are presented here as an aid to administrators of radon control programmes, companies offering radon testing and mitigation services and other concerned parties, both in Canada and elsewhere, who are facing issues of implementing a radon control strategy. A wide variety of radon mitigation strategies have been employed worldwide and all have achieved some success in reducing radon concentrations. Generally, active mitigation techniques involving physical alterations to a house (e.g. sub-slab depressurisation) are more effective in achieving a sustained and substantial radon reduction than passive techniques (e.g. improved ventilation or sealing of cracks). To a large extent, the choice of an optimal mitigation strategy will depend on the building type, soil conditions and climate. Radon levels should be measured at periodic intervals after remediation, perhaps once every 5 y, to ensure that concentrations continue to remain at acceptable levels.

  16. A theoretical investigation of the distribution of indoor radon concentrations

    Science.gov (United States)

    Rabi, R.; Oufni, L.

    2017-05-01

    Inhalation of radon (222Rn) and its decay products are a major source of natural radiation exposure. It is known from recent surveys in many countries that radon and its progeny contribute significantly to total inhalation dose and it is fairly established that radon when inhaled in large quantity causes lung disorder. In recent times, numerical modelling has become the cost effective replacement of experimental methods for the prediction and visualization of indoor pollutant distribution. The aim of this study is to implement the Finite Volume Method (FVM) for studying the radon distribution indoor. The findings show that the radon concentration which is distributed in a non-homogeneous way in the room is due to the difference in the radon concentration of different sources (wall, floor and ceiling). Moreover, the radon concentration is much larger near walls, and decreases in the middle of the room because of the effect of air velocity. We notice that the simulation results of radon concentration are in agreement with the results of other experimental studies. The annual effective dose of radon in the model room has been also investigated.

  17. Estimation of radon concentration in dwellings in and around Guwahati

    Science.gov (United States)

    Dey, Gautam Kumar; Das, Projit Kumar

    2012-02-01

    It has been established that radon and its airborne decay products can present serious radiation hazards. A long term exposure to high concentration of radon causes lung cancer. Besides, it is also known that out of the total radiation dose received from natural and man-made sources, 60% of the dose is due to radon and its progeny. Taking this into account, an attempt has been made to estimate radon concentration in dwellings in and around Guwahati using aluminium dosimeter cups with CR-39 plastic detectors. Results of preliminary investigation presented in this paper show that the mean concentration is 21.31 Bq m - 3.

  18. The effect of laterite density on radon diffusion behavior.

    Science.gov (United States)

    Li, Yongmei; Tan, Wanyu; Tan, Kaixuan; Liu, Zehua; Fang, Qi; Lv, Junwen; Duan, Xianzhe; Liu, Zhenzhong; Guo, Yueyue

    2018-02-01

    Radon generated in porous media such as soils and rocks migrates into indoor and outdoor air mainly by diffusion, possessing significant hazards to human health. In order to reduce these hazards of radon, it is of great importance to study the diffusion behavior of radon. In this study, we systematically measured the radon diffusion coefficient of laterite with the density ranging from 0.917gcm -3 to 2.238gcm -3 , and studied the effect of laterite density on the radon diffusion. The results show that the radon diffusion coefficient of the laterite generally decreases with the increasing laterite density. In addition, three possible relationships between the radon diffusion coefficient and the laterite density are found out as follows: (1) the linear correlation with a slope of -4.48 × 10 -6 for laterite with density ranging from 0.917 to 1.095gcm -3 , (2) the exponential correlation for laterite with density from 1.095 to 1.63gcm -3 , (3) linear correlation with a slope of -3.1 × 10 -7 for laterite with density from 1.63 to 2.238gcm -3 . The complex relationship between the radon diffusion coefficient and density is caused by the change of porosity and tortuosity of the laterite. Therefore, we suggest that a suitable density should be adopted while using the laterite to effectively cover uranium tailings or economically produce building materials that can curb the radon exhalation. Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. Radon exhalation from building materials used in Libya

    Science.gov (United States)

    Saad, A. F.; Al-Awami, Hend H.; Hussein, N. A.

    2014-08-01

    Radon exhalation rates have been determined for various different samples of domestic and imported building materials available in the Libyan market for home construction and interior decoration. Radon exhalation rates were measured by the sealed-can technique based on CR-39 nuclear track detectors (NTDs). The results show that radon exhalation rates from some imported building materials used as foundations and for decoration are extremely high, and these samples are the main sources of indoor radon emanation. Radium contents and annual effective doses have also been estimated.

  20. Impact of different vertical transport representations on simulating processes in the tropical tropopause layer (TTL)

    Energy Technology Data Exchange (ETDEWEB)

    Ploeger, Felix

    2011-07-06

    The chemical and dynamical processes in the tropical tropopause layer (TTL) control the amount of radiatively active species like water vapour and ozone in the stratosphere, and hence turn out to be crucial for atmospheric trends and climate change. Chemistry transport models and chemistry climate models are suitable tools to understand these processes. But model results are subject to uncertainties arising from the parametrization of model physics. In this thesis the sensitivity of model predictions to the choice of the vertical transport representation will be analysed. Therefore, backtrajectories are calculated in the TTL, based on different diabatic and kinematic transport representations using ERA-Interim and operational ECMWF data. For diabatic transport on potential temperature levels, the vertical velocity is deduced from the ERA-Interim diabatic heat budget. For kinematic transport on pressure levels, the vertical wind is used as vertical velocity. It is found that all terms in the diabatic heat budget are necessary to cause transport from the troposphere to the stratosphere. In particular, clear-sky heating rates alone miss very important processes. Many characteristics of transport in the TTL turn out to depend very sensitively on the choice of the vertical transport representation. Timescales for tropical troposphere-to-stratosphere transport vary between one and three months, with respect to the chosen representation. Moreover, for diabatic transport ascent is found throughout the upper TTL, whereas for kinematic transport regions of mean subsidence occur, particularly above the maritime continent. To investigate the sensitivity of simulated trace gas distributions in the TTL to the transport representation, a conceptual approach is presented to predict water vapour and ozone concentrations from backtrajectories, based on instantaneous freeze-drying and photochemical ozone production. It turns out that ozone predictions and vertical dispersion of the

  1. Strategy for the reduction of radon exposure in Norway

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2010-05-15

    Elevated indoor radon concentrations are a more extensive problem in Norway than in many other countries. It has been estimated that indoor radon causes approximately 300 deaths from lung cancer each year in Norway. On average, avoiding lung cancer increases life expectancy by 14 to 18 years. Radon is a radioactive noble gas formed continually is a decay product from uranium. Uranium is a natural constituent existing in varying concentrations in bedrock, minerals and soils. For this reason, both the soil air and groundwater contain radon. Radon in buildings normally originates from the soil air in the underlying ground. Indoor air pressure is often low, so that radon-containing air from the surrounding ground gets sucked in through cracks in the building foundations. Elevated indoor radon concentrations can be due to household water drawn from groundwater wells, and radon gas can also be emitted from building materials such as certain types of stone or concrete containing high levels of natural radioactivity. Norway, Sweden and Finland are among the the countries in the world with the highest average indoor radon concentrations. Geological conditions and the cool climate pose a big challenge, but the radon problem can be solved in a cost-effective way. Radon is the most common cause of lung cancer after active smoking. At a radon concentration of 100 Bq/m3, which is not far from the estimated average for Norwegian housing, the risks of dying of radon-induced lung cancer before the age of 75 are 0.1 % for non-smokers and 2 % for smokers, respectively. Many buildings in Norway have radon levels that exceed this. The most important health impact of radon exposure is the increased risk of lung cancer. This increase in risk is assumed to be linear in relation to radon concentration (i.e., the risk is 10 times higher at 1000 Bq/m3 compared to 100 Bq/m3). The risk also increases linearly with exposure time, i.e. there is a tenfold greater risk of contracting lung cancer

  2. Monitoring of radon activity in natural sources of drinking water near Ekaterinburg city

    Energy Technology Data Exchange (ETDEWEB)

    Semenischev, Vladimir S.; Lezhnina, Marina Ju. [Ural federal university, 620002 Ekaterinburg (Russian Federation)

    2014-07-01

    25 - 30 L/min in spring and summer. Meanwhile, it was shown that the specific activity of radon was almost constant during the whole year (insignificantly higher in summer), at the average 93 Bq/L. It indicates that migration of radon with water from place of its formation in winter is approximately 3 times lower than in summer; this could be explained through decreasing of kinetics of this process at low temperatures. (authors)

  3. The Assessment of the Integrated Antioxidant System of the Body in the Course of Radon Therapy: A Pilot Study

    Directory of Open Access Journals (Sweden)

    Jadwiga Kuciel-Lewandowska

    2018-01-01

    Full Text Available Introduction. The sources of Reactive Oxidative Species (ROS in the organism are the respiratory processes occurring in cells catalyzed by different enzymes. Operation of ROS is balanced by antioxidants, the compounds; although present in low concentrations, they significantly inhibit the degree of oxidation of particular molecules. The Aim of the Study. The aim of this study was to assess the changes in the integrated antioxidant system under the influence of radon therapy in osteoarthritis patients. Material and Methods. Observation included 35 patients suffering from degenerative joints and disc disease (mean age 56.5 years undergoing radon water therapy and control group that consisted of 15 osteoarthritis patients (mean age 54.2 without contact with radon water. Before therapy and after 18 days of treatment, serum total antioxidant status (TAS was assessed with the use of standard colorimetric assay. Results. In the study group, we observed trends to increase TAS concentration, whereas, in the control group, TAS concentration was decreasing. Conclusions. (1 Radon waters treatment influenced the level of TAS of osteoarthritis patients treated with the radon water. (2 The change in TAS concentrations in the study group may be the result of low doses of ionizing radiation, but further studies on larger patient’s groups are demanded. This study is registered with number NCT03274128.

  4. Shallow circulation groundwater – the main type of water containing hazardous radon concentration

    Directory of Open Access Journals (Sweden)

    T. A. Przylibski

    2011-06-01

    Full Text Available The main factors affecting the value of 222Rn activity concentration in groundwater are the emanation coefficient of reservoir rocks (Kem, the content of parent 226Ra in these rocks (q, changes in the volume and flow velocity as well as the mixing of various groundwater components in the circulation system. The highest values of 222Rn activity concentration are recorded in groundwaters flowing towards an intake through strongly cracked reservoir rocks undergoing weathering processes. Because of these facts, waters with hazardous radon concentration levels, i.e. containing more than 100 Bq dm−3 222Rn, could be characterised in the way that follows. They are classified as radon waters, high-radon waters and extreme-radon waters. They belong to shallow circulation systems (at less than a few dozen metres below ground level and are contemporary infiltration waters, i.e. their underground flow time ranges from several fortnights to a few decades. Because of this, these are usually poorly mineralised waters (often below 0.2–0.5 g dm−3. Their resources are renewable, but also vulnerable to contamination.

    Waters of this type are usually drawn from private intakes, supplying water to one or at most a few households. Due to an increased risk of developing lung tumours, radon should be removed from such waters when still in the intake. To achieve this aim, appropriate legislation should be introduced in many countries.

  5. A Proactive Complex Event Processing Method for Large-Scale Transportation Internet of Things

    OpenAIRE

    Yongheng Wang; Kening Cao

    2014-01-01

    The Internet of Things (IoT) provides a new way to improve the transportation system. The key issue is how to process the numerous events generated by IoT. In this paper, a proactive complex event processing method is proposed for large-scale transportation IoT. Based on a multilayered adaptive dynamic Bayesian model, a Bayesian network structure learning algorithm using search-and-score is proposed to support accurate predictive analytics. A parallel Markov decision processes model is design...

  6. Control of Molecular Ordering, Alignment, and Charge Transport in Solution-Processed Conjugated Polymer Thin Films

    Directory of Open Access Journals (Sweden)

    Mincheol Chang

    2017-06-01

    Full Text Available Morphology of conjugated polymers is a critical factor that significantly affects intrinsic charge transport characteristics and in turn performance of polymer-based devices. Morphological defects including misaligned crystalline grains and grain boundaries significantly impede efficient charge hopping between transport sites, resulting in degradation of device performance. Therefore, one important challenge is to control morphology of active polymer thin-films for achieving high performance flexible electronic devices. In the past decade, significant progress has been achieved in morphology control of conjugated polymer thin-films using solution-based processing techniques. This review focuses on recent advances in processing strategies that can tune the morphologies and thus impact charge transport properties of conjugated polymer thin films. Of the available processing strategies, polymer solution treatments and film deposition techniques will be mainly highlighted. The correlation between processing conditions, active layer morphologies, and device performance will be also be discussed.

  7. Signal processing of bedload transport impact amplitudes on accelerometer instrumented plates

    Science.gov (United States)

    This work was performed to help establish a data processing methodology for relating accelerometer signals caused by impacts of gravel on steel plates to the mass and size of the transported material. Signal processing was performed on impact plate data collected in flume experiments at the Nationa...

  8. Radon in soil concentration levels in Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Segovia, N.; Tamez, E.; Mena, M

    1991-09-15

    Radon in soil surveys in Mexico have been carried out since 1974 both for uranium prospectus and to correlate mean values of the gas emanation with local telluric behaviour. The mapping includes the northern uranium mining region, the Mexican Neo volcanic Belt, the coastal areas adjacent to the zone of subduction of the Cocos Plate under the North American Plate, some of the active volcanoes of Southern Mexico and several sedimentary valleys in Central Mexico. Recording of {sup 222} Rn alpha decay is systematically performed with LR115 track detectors. Using mean values averaged over different observation periods at fixed monitoring stations, a radon in soil map covering one third of the Mexican territory is presented. The lowest mean values have been found in areas associated with active volcanoes. The highest levels are found in uranium ore zones. Intermediate values are obtained in regions with enhanced hydrothermal activity and stations associated with intrusive rocks. (Author)

  9. Behavior of radon and its decay products in physical media; Comportamiento de radon y sus productos en medios fisicos

    Energy Technology Data Exchange (ETDEWEB)

    Chavez B, A

    1990-06-15

    This study was carried out to know the radon behavior, it shows some of its decay products of short life, the same as the equations that describe the growth of the activity of each decay product in a source that initially is radon. The study threw results that they are applicable in geology, uranium prospecting, as well as in radiological safety. The use of membranes to filter the decay products of radon and the use of these for protection of the detector, it has opened a new line in the study of the radon. (Author)

  10. Design, construction and testing of a radon experimental chamber; Diseno, construccion y pruebas de una camara experimental de radon

    Energy Technology Data Exchange (ETDEWEB)

    Chavez B, A.; Balcazar G, M

    1991-10-15

    To carry out studies on the radon behavior under controlled and stable conditions it was designed and constructed a system that consists of two parts: a container of mineral rich in Uranium and an experimentation chamber with radon united one to the other one by a step valve. The container of uranium mineral approximately contains 800 gr of uranium with a law of 0.28%; the radon gas emanated by the mineral is contained tightly by the container. When the valve opens up the radon gas it spreads to the radon experimental chamber; this contains 3 accesses that allow to install different types of detectors. The versatility of the system is exemplified with two experiments: 1. With the radon experimental chamber and an associated spectroscopic system, the radon and two of its decay products are identified. 2. The design of the system allows to couple the mineral container to other experimental geometries to demonstrate this fact it was coupled and proved a new automatic exchanger system of passive detectors of radon. The results of the new automatic exchanger system when it leave to flow the radon freely among the container and the automatic exchanger through a plastic membrane of 15 m. are shown. (Author)

  11. A study of radon indoor concentration; Un estudio de concentracion de radon intramuros

    Energy Technology Data Exchange (ETDEWEB)

    Pena, P.; Ruiz, W.; Segovia, N.; Ponciano, G. [ININ, Gerencia de Ciencias Ambientales, A.P. 18-1027, 11801 Mexico D.F. (Mexico)

    2000-07-01

    It was realized a study of radon concentration in houses of Mexico City and in a laboratory of the Nuclear Centre of Salazar, State of Mexico. The radon determination in air was realized with solid nuclear track detectors and with Honeywell and Alpha guard automatic equipment. The results show that the majority of houses have values under 148 Bq/m{sup 3} obtaining some housings with upper values located in the Lomas zone. A study in smokers houses and another of controls showed very similar distributions. It was studied the day time fluctuations finding that radon increases considerably during the dawn. Some upper values obtained in a laboratory of the Nuclear Centre were remedied with ventilation. (Author)

  12. Estimation of human dose to radon progeny

    Energy Technology Data Exchange (ETDEWEB)

    Shimo, Michikuni [Gifu Coll. of Medical Technology, Sekiichi, Gifu (Japan)

    1996-12-01

    The aim of the paper is the estimation of the effective dose due to radon progeny for Japanese population. The estimation was performed by a modified UNSCEAR equation. The equation was needed the radon concentration annual occupancy time and the tidal volume on Japanese people and the dose conversion coefficient are needed. Furthermore, not only these figures but also unattached fraction and aerosol distribution data obtained in Japan and the factor related to the Japanese living style were used in the calculation. We used following figures as representative value in Japan; radon concentration: 13(6 - 25) Bq/m{sup 3} indoors and 6.7(3.5 - 13) Bq/m{sup 3} outdoors; the equilibrium factor: 0.45(0.35 - 0.57) indoors and 0.70(0.50 - 0.90) outdoors; the occupancy factor: 0.87 indoors, 0.09 outdoors and 0.04 in vehicle for male and 0.91 indoors, 0.06 outdoors and 0.03 in vehicle for female; the tidal volume: 7,000 (4,000 - 8,000) m{sup 3} for male, 6,200 (3,500 - 7,500) m{sup 3} for female. The effective doses due to radon progeny were estimated to be 0.45 mSv/y for male and 0.40 mSv/y for female, and the variance was -80 - +130%. These values were 1/2 - 1/3 as small as values shown by UNSCEAR 1993 Report and estimated by ICRP Publication 65. (author)

  13. Radon assay and radioactivity database in Kamioka

    Science.gov (United States)

    Takeuchi, Yasuo; Tasaka, Shigeki; Nakano, Yuuki

    2017-09-01

    A new cooperative program among underground experiments, theorists, and low-background researchers was started in 2014 in Japan. The purpose of this program is to achieve technical and scientific synergies among underground researchers. In this report, the R&D of radon assay technique as an activity in this program is shown. The current status of the radioactivity database system in Kamioka is also shown.

  14. Radon-Nikodym derivatives of quantum instruments

    Science.gov (United States)

    Holevo, A. S.

    1998-03-01

    A convenient representation for Radon-Nikodym derivatives of completely positive (c.p.) instruments on B(H) with respect to a scalar measure is suggested, similar to the Stinespring-Kraus representation for c.p. maps, but involving possibly nonclosable unbounded operators. The structure of covariant c.p. instruments is studied in detail. In particular, an exhaustive description is given to instruments covariant with respect to shifts or rotations, corresponding to "position" or "angle" measurements.

  15. An Analytic Hierarchy Process for The Evaluation of Transport Policies to Reduce Climate Change Impacts

    OpenAIRE

    Berrittella, Maria; Certa, A; Enea, M; Zito, P.

    2007-01-01

    Transport is the sector with the fastest growth of greenhouse gases emissions, both in developed and in developing countries, leading to adverse climate change impacts. As the experts disagree on the occurrence of these impacts, by applying the analytic hierarchy process (AHP), we have faced the question on how to form transport policies when the experts have different opinions and beliefs. The opinions of experts have been investigated by a means of a survey questionnaire. The results show t...

  16. Littoral transport rates in the Santa Barbara Littoral Cell: a process-based model analysis

    Science.gov (United States)

    Elias, E. P. L.; Barnard, Patrick L.; Brocatus, John

    2009-01-01

    Identification of the sediment transport patterns and pathways is essential for sustainable coastal zone management of the heavily modified coastline of Santa Barbara and Ventura County (California, USA). A process-based model application, based on Delft3D Online Morphology, is used to investigate the littoral transport potential along the Santa Barbara Littoral Cell (between Point Conception and Mugu Canyon). An advanced optimalization procedure is applied to enable annual sediment transport computations by reducing the ocean wave climate in 10 wave height - direction classes. Modeled littoral transport rates compare well with observed dredging volumes, and erosion or sedimentation hotspots coincide with the modeled divergence and convergence of the transport gradients. Sediment transport rates are strongly dependent on the alongshore variation in wave height due to wave sheltering, diffraction and focusing by the Northern Channel Islands, and the local orientation of the geologically-controlled coastline. Local transport gradients exceed the net eastward littoral transport, and are considered a primary driver for hot-spot erosion.

  17. Modeling the coupled mechanics, transport, and growth processes in collagen tissues.

    Energy Technology Data Exchange (ETDEWEB)

    Holdych, David J.; Nguyen, Thao D.; Klein, Patrick A.; in' t Veld, Pieter J.; Stevens, Mark Jackson

    2006-11-01

    The purpose of this project is to develop tools to model and simulate the processes of self-assembly and growth in biological systems from the molecular to the continuum length scales. The model biological system chosen for the study is the tendon fiber which is composed mainly of Type I collagen fibrils. The macroscopic processes of self-assembly and growth at the fiber scale arise from microscopic processes at the fibrillar and molecular length scales. At these nano-scopic length scales, we employed molecular modeling and simulation method to characterize the mechanical behavior and stability of the collagen triple helix and the collagen fibril. To obtain the physical parameters governing mass transport in the tendon fiber we performed direct numerical simulations of fluid flow and solute transport through an idealized fibrillar microstructure. At the continuum scale, we developed a mixture theory approach for modeling the coupled processes of mechanical deformation, transport, and species inter-conversion involved in growth. In the mixture theory approach, the microstructure of the tissue is represented by the species concentration and transport and material parameters, obtained from fibril and molecular scale calculations, while the mechanical deformation, transport, and growth processes are governed by balance laws and constitutive relations developed within a thermodynamically consistent framework.

  18. Influence of architectural style on indoor radon concentration in a radon prone area: A case study.

    Science.gov (United States)

    Baeza, A; García-Paniagua, J; Guillén, J; Montalbán, B

    2018-01-01

    Indoor radon is a major health concern as it is a known carcinogenic. Nowadays there is a trend towards a greater energy conservation in buildings, which is reflected in an increasing number of regulations. But, can this trend increase the indoor radon concentration? In this paper, we selected a radon prone area in Spain and focused on single-family dwellings constructed in a variety of architectural styles. These styles ranged from 1729 up to 2014, with varying construction techniques (from local resources to almost universally standard building materials) and regulations in force (from none to the Spanish regulation in force). The (226)Ra concentrations in soil and surface radon exhalation rates were rather similar in this area, mean values ranging 70-126Bq/kg and 49-100mBq/m(2)·s, respectively. Indoor radon concentration was generally greater than the contribution from soil exhalation (surface exhalation rates), especially in New dwellings (1980-2014). Its concentration in dwellings built in the Traditional style (1729-1940) was significantly lower than in the new houses. This can be consequence of the air tightness of the dwellings as a consequence of the different regulations in force. In the period covered by the Traditional style, there was no regulation in force, and dwelling had loose air tight. Whereas in recent times, there are mandatory regulations assuring a better air tightness of the buildings. Refurbishment of Traditional dwellings also seems to increase the indoor radon concentration, as they must also comply with the regulations in force. Copyright © 2017 Elsevier B.V. All rights reserved.

  19. Residential radon remediation: performance over 17 years.

    Science.gov (United States)

    Harley, Naomi H; Chittaporn, Passaporn; Marsicano, Anthony

    2011-05-01

    An exploratory radon measurement in 1990 identified 190 Bq m(-3) in the basement of a newly built home in Central New Jersey. Subsequently, the owner had a sub-slab remediation system installed in the basement, i.e. PVC duct through the basement floor connecting to an exhaust fan venting to the house roof. Sequential radon measurements began in 1992 using the NYU alpha-track detector. The homeowner wanted to insure the long-term durability of this remedial system. Seventeen years of measurements show the system functioned properly and reduced an established baseline concentration of 370 ± 8, 56 ± 1 and 67 ± 1 Bq m(-3) for the basement, first and second floors, respectively, to an average of 19 ± 4, 13 ± 3 and 10 ± 0.1 Bq m(-3). The last measurement, 2007-2008, with a newer NYU detector measured both (222)Rn (radon) and (220)Rn (thoron). The basement thoron concentration was 1.5 ± 0.9 Bq m(-3) or about 8 % of the (222)Rn value.

  20. Sex and smoking sensitive model of radon induced lung cancer

    Energy Technology Data Exchange (ETDEWEB)

    Zhukovsky, M.; Yarmoshenko, I. [Institute of Industrial Ecology of Ural Branch of Russian Academy of Sciences, Yekaterinburg (Russian Federation)

    2006-07-01

    Radon and radon progeny inhalation exposure are recognized to cause lung cancer. Only strong evidence of radon exposure health effects was results of epidemiological studies among underground miners. Any single epidemiological study among population failed to find reliable lung cancer risk due to indoor radon exposure. Indoor radon induced lung cancer risk models were developed exclusively basing on extrapolation of miners data. Meta analyses of indoor radon and lung cancer case control studies allowed only little improvements in approaches to radon induced lung cancer risk projections. Valuable data on characteristics of indoor radon health effects could be obtained after systematic analysis of pooled data from single residential radon studies. Two such analyses are recently published. Available new and previous data of epidemiological studies of workers and general population exposed to radon and other sources of ionizing radiation allow filling gaps in knowledge of lung cancer association with indoor radon exposure. The model of lung cancer induced by indoor radon exposure is suggested. The key point of this model is the assumption that excess relative risk depends on both sex and smoking habits of individual. This assumption based on data on occupational exposure by radon and plutonium and also on the data on external radiation exposure in Hiroshima and Nagasaki and the data on external exposure in Mayak nuclear facility. For non-corrected data of pooled European and North American studies the increased sensitivity of females to radon exposure is observed. The mean value of ks for non-corrected data obtained from independent source is in very good agreement with the L.S.S. study and Mayak plutonium workers data. Analysis of corrected data of pooled studies showed little influence of sex on E.R.R. value. The most probable cause of such effect is the change of men/women and smokers/nonsmokers ratios in corrected data sets in North American study. More correct

  1. A COMPARISON OF WINTER SHORT-TERM AND ANNUAL AVERAGE RADON MEASUREMENTS IN BASEMENTS OF A RADON-PRONE REGION AND EVALUATION OF FURTHER RADON TESTING INDICATORS

    Science.gov (United States)

    Barros, Nirmalla G.; Steck, Daniel J.; Field, R. William

    2014-01-01

    The primary objective of this study was to investigate the temporal variability between basement winter short-term (7 to 10 days) and basement annual radon measurements. Other objectives were to test the short-term measurement’s diagnostic performance at two reference levels and to evaluate its ability to predict annual average basement radon concentrations. Electret ion chamber (short-term) and alpha track (annual) radon measurements were obtained by trained personnel in Iowa residences. Overall, the geometric mean of the short-term radon concentrations (199 Bq m−3) was slightly greater than the geometric mean of the annual radon concentrations (181 Bq m−3). Short-term tests incorrectly predicted that the basement annual radon concentrations would be below 148 Bq m−3 12% of the time and 2% of the time at 74 Bq m−3. The short-term and annual radon concentrations were strongly correlated (r=0.87, pradon potential when the reference level is lowered to 74 Bq m−3. PMID:24670901

  2. Transportation

    Science.gov (United States)

    2006-01-01

    container. It now permits free transit of shipping containers from their western ports, if transported by rail directly to the U.S. ( Mireles , 2005, p...Transportation Industry Study Seminar. Mireles , Richard, Castillo. (2005, January). A Cure for West Coast Congestion. Logistics Today, Vol. 46, Issue 1. 1

  3. Nonequilibrium thermodynamics transport and rate processes in physical, chemical and biological systems

    CERN Document Server

    Demirel, Yasar

    2014-01-01

    Natural phenomena consist of simultaneously occurring transport processes and chemical reactions. These processes may interact with each other and may lead to self-organized structures, fluctuations, instabilities, and evolutionary systems. Nonequilibrium Thermodynamics, 3rd edition emphasizes the unifying role of thermodynamics in analyzing the natural phenomena. This third edition updates and expands on the first and second editions by focusing on the general balance equations for coupled processes of physical, chemical, and biological systems. The new edition contains a new chapte

  4. Electronic repository and standardization of processes and electronic documents in transport

    Directory of Open Access Journals (Sweden)

    Tomasz DĘBICKI

    2007-01-01

    Full Text Available The article refers to the idea of the use of electronic repository to store standardised scheme of processes between a Logistics Service Provider and its business partners. Application of repository for automatic or semi-automatic configuration of interoperability in electronic data interchange between information systems of differentcompanies based on transport (road, rail, sea and combined related processes. Standardisation includes processes, scheme of cooperation and related to them, electronic messages.

  5. A vadose zone Transport Processes Investigation within the glacial till at the Fernald Environmental Management Project.

    Energy Technology Data Exchange (ETDEWEB)

    Schwing, J. (FERMCO Technology Development, Cincinnati, OH); Roepke, Craig Senninger; Brainard, James Robert; Glass, Robert John, Jr.; Mann, Michael J. A.; Holt, Robert M.; Kriel, Kelly

    2007-08-01

    This report describes a model Transport Processes Investigation (TPI) where field-scale vadose zone flow and transport processes are identified and verified through a systematic field investigation at a contaminated DOE site. The objective of the TPI is to help with formulating accurate conceptual models and aid in implementing rational and cost effective site specific characterization strategies at contaminated sites with diverse hydrogeologic settings. Central to the TPI are Transport Processes Characterization (TPC) tests that incorporate field surveys and large-scale infiltration experiments. Hypotheses are formulated based on observed pedogenic and hydrogeologic features as well as information provided by literature searches. The field and literature information is then used to optimize the design of one or more infiltration experiments to field test the hypothesis. Findings from the field surveys and infiltration experiments are then synthesized to formulate accurate flow and transport conceptual models. Here we document a TPI implemented in the glacial till vadose zone at the Fernald Environmental Management Project (FEMP) in Fernald, Ohio, a US Department of Energy (DOE) uranium processing site. As a result of this TPI, the flow and transport mechanisms were identified through visualization of dye stain within extensive macro pore and fracture networks which provided the means for the infiltrate to bypass potential aquatards. Such mechanisms are not addressed in current vadose zone modeling and are generally missed by classical characterization methods.

  6. The peculiarities of process-based approach realization in transport sector company management

    Science.gov (United States)

    Khripko, Elena; Sidorov, Gennadiy

    2017-10-01

    In the present article we study the phenomena of multiple meaning in understanding process-based management method in construction of transport infrastructure facilities. The idea of multiple meaning is in distortions which appear during reception of the management process paradigm in organizational environment of transport sector. The cause of distortion in process management is organizational resistance. The distortions of management processes are discovered at the level of diffusion among spheres of responsibility, collision in forms of functional, project and process interaction between the owner of the process and its participants. The level of distortion is affected by the attitude towards the result of work which means that process understanding of the result is replaced by the functional one in practice of management. This transfiguration is the consequence of regressive defensive mechanisms of the organizational environment. On the base of experience of forming process management in construction of transport infrastructure facilities company of the issues of diagnostics of various forms of organizational resistance and ways of reducing the destructive influence on managing processes are reviewed.

  7. Design Criteria for Achieving Acceptable Indoor Radon Concentration

    DEFF Research Database (Denmark)

    Rasmussen, Torben Valdbjørn

    2016-01-01

    in most countries. The three design criteria are; first, establishing a radon barrier facing the ground; second, lowering the air pressure in the lower zone of the slab on ground facing downwards; third, diluting the indoor air with outdoor air. The first two criteria can prevent radon from infiltrating...

  8. Anomalous soil radon fluctuations – signal of earthquakes in Nepal ...

    Indian Academy of Sciences (India)

    . (2005a) and Yang et al. (2005) carried out a study on the variation of radon-222 in sub-soil ... (1995) in Central America and. Mexico, Planinic et al. (2000) in Croatia studied the temporal variation of soil radon-222 concentra- tion in search of ...

  9. Radon in Rented Accommodation and Variables Determining Its Level

    DEFF Research Database (Denmark)

    Rasmussen, Torben Valdbjørn

    2017-01-01

    Bq/m3 in 5.9% of the homes. Of the investigated variables, only homes in single-family terraced houses, were statistically significant. Approx. 75% of homes exceeding 100 Bq/m3 indoor radon level had levels between 100 and 200 Bq/m3 and 25% had indoor radon levels exceeding 200 Bq/m3. Significant...

  10. National Radon Awareness Month - Event Planning Kit Document

    Science.gov (United States)

    Individuals, groups, and organizations are the driving force in getting the message out to the public about the dangers of indoor radon. You will find information and materials in this Kit that you can use to get the word out about radon.

  11. Molecular dynamics simulations of radon accumulation in water and oil

    Energy Technology Data Exchange (ETDEWEB)

    Pafong, Elvira; Drossel, Barbara [Institut fuer Festkoerperphysik, Technische Universitaet Darmstadt (Germany)

    2016-07-01

    Radon is a radioactive gas that can enter the human body from air or from ground water. Radon can accumulate to levels that considerably rise the risk of lung cancer while it is also known as a a treatment of various ailments, most notably rheumatoid arthritis. The accumulation of radon differs between tissues, with particularly high concentrations in fatty cells. In order to understand the mechanisms responsible for the different solubility of radon in water and fat, we perform molecular dynamics simulations of radon gas at ambient conditions in contact with a bulk material consisting either of water or oil. We evaluate the diffusion coefficient of radon in both media as well as the equilibrium concentration. The crucial point here is to understand the hydrophobic interaction between water and radon as compared to the dispersive interaction between radon and oil. Therefore, we artificially vary the water charges (i.e., the hydrophobicity) as well as the parameters of the van-der-Waals interaction.

  12. Rotation-invariant fingerprint matching using radon and DCT

    Indian Academy of Sciences (India)

    A new set of promising rotation-invariant features based on radon and discrete cosine transform (DCT) is proposed for fingerprint matching. The radon and DCT of a tiny area in the region of core point of fingerprint image is computed. In the proposed method only 34% DCT coefficients are used for feature extraction.

  13. Environmental Radon Gas and Degenerative Conditions An Overview

    Energy Technology Data Exchange (ETDEWEB)

    Groves-Kirkby, C.J. [Medical Physics Department, Northampton General Hospital, Northampton NN1 5BD (United Kingdom)]|[School of Health, University of Northampton, Northampton NN2 7AL (United Kingdom); Denman, A.R. [Medical Physics Department, Northampton General Hospital, Northampton NN1 5BD (United Kingdom); Woolridge, A.C. [School of Health, University of Northampton, Northampton NN2 7AL (United Kingdom)]|[School of Applied Sciences, University of Northampton, Northampton NN2 7AL (United Kingdom); Phillips, P.S. [School of Applied Sciences, University of Northampton, Northampton NN2 7AL (United Kingdom); Phillips, C. [School of Health, University of Northampton, Northampton NN2 7AL (United Kingdom)

    2006-07-01

    Radon, a naturally occurring radioactive gas, has variable distribution in the environment as a decay product of uranium occurring in a wide range of rocks, soils and building materials. Although radon dissipates rapidly in outdoor air, it concentrates in the built environment, and inhalation of {sup 222}Rn and its progeny {sup 218}Po and {sup 214}Po is believed to provide the majority of the radioactive dose to the respiratory system. While the connection between radon and lung cancer has long been recognised and investigated, recent studies have highlighted potential links between radon and other conditions, among them Multiple Sclerosis, Alzheimer and Parkinson Diseases, and Paget Disease of Bone. A strong case exists for clarifying the relationship between radon and these other conditions, not least since radon remediation to reduce lung cancer may conceivably have additional benefits hitherto unrecognized. The present status of the postulated links between environmental radon gas and degenerative conditions is reviewed, and recommendations for further research into levering current anti-radon campaigns are made. (authors)

  14. A national survey on radon remediation in Switzerland.

    Science.gov (United States)

    Barazza, Fabio Daniel; Murith, Christophe; Palacios, Martha; Gfeller, Walther; Christen, Emanuel

    2017-11-02

    We present and discuss the results of a national survey on radon remediation. The main purpose of the survey was the evaluation of the rate of radon remediation in Switzerland and to identify the main reasons for not taking action in cases of high radon levels. Switzerland is strongly affected by the radon problem and extensive efforts have been made to map the radon potential and to investigate the most effective methods to reduce radon levels in different buildings. However, since the radon remediation of buildings has been given over to experts in the private sector and since there is no obligation to report a finished remediation to the authorities, it is difficult for the Federal Office for Public Health (FOPH) to track the activities in this field. In order to improve this situation, the FOPH has launched a survey. We find a rate of radon remediation of 46%. The most often applied method is the aeration of the cellar and the improvement of the tightness of the floor slab. The respondents indicate that the most important reason for not taking action is the concern about the financial and/or invasive magnitude of the work. We discuss the different outcomes of the survey in the three linguistic regions in Switzerland and identify aspects of our communication with the public, which should be improved in view of our findings. © 2017 IOP Publishing Ltd.

  15. Soil Radon In The Nigerian Younger Granites | Dewu | Nigerian ...

    African Journals Online (AJOL)

    ... not had enough time to attain equilibrium with its daughters. In general, the results suggest that with proper control, soil radon measurements over the Younger Granite can be used for uranium exploration in the region. Keywords: Radon, younger granite, soil uranium, half-lifeand thorium. Nigerian Journal of Physics Vol.

  16. Reporting on Radon: The Role of Local Newspapers.

    Science.gov (United States)

    Post, James F.; And Others

    Noting that past local media coverage of environmental topics, including those dealing with radiation topics, has often been superficial, a study assessed press coverage of the radon problem in the Lehigh Valley region of Pennsylvania during the first nine months of 1985. The study explored whether local media coverage of radon--a colorless,…

  17. Measurements of radon activity concentration in mouse tissues and organs.

    Science.gov (United States)

    Ishimori, Yuu; Tanaka, Hiroshi; Sakoda, Akihiro; Kataoka, Takahiro; Yamaoka, Kiyonori; Mitsunobu, Fumihiro

    2017-05-01

    The purpose of this study is to investigate the biokinetics of inhaled radon, radon activity concentrations in mouse tissues and organs were determined after mice had been exposed to about 1 MBq/m(3) of radon in air. Radon activity concentrations in mouse blood and in other tissues and organs were measured with a liquid scintillation counter and with a well-type HP Ge detector, respectively. Radon activity concentration in mouse blood was 0.410 ± 0.016 Bq/g when saturated with 1 MBq/m(3) of radon activity concentration in air. In addition, average partition coefficients obtained were 0.74 ± 0.19 for liver, 0.46 ± 0.13 for muscle, 9.09 ± 0.49 for adipose tissue, and 0.22 ± 0.04 for other organs. With these results, a value of 0.414 for the blood-to-air partition coefficient was calculated by means of our physiologically based pharmacokinetic model. The time variation of radon activity concentration in mouse blood during exposure to radon was also calculated. All results are compared in detail with those found in the literature.

  18. RADON DIAGNOSTIC MEASUREMENT GUIDANCE FOR LARGE BUILDINGS - VOLUME 2. APPENDICES

    Science.gov (United States)

    The report discusses the development of radon diagnostic procedures and mitigation strategies applicable to a variety of large non-residential buildings commonly found in Florida. The investigations document and evaluate the nature of radon occurrence and entry mechanisms for rad...

  19. Methods for measuring diffusion coefficients of radon in building materials

    NARCIS (Netherlands)

    Cozmuta, [No Value; van der Graaf, ER

    2001-01-01

    Two methods for determining the Rn-222 diffusion coefficient in concrete are presented. Experimentally, the flush and adsorption technique to measure radon release rates underlines both methods. Theoretically, the first method was developed fur samples of cubical geometry. The radon diffusion

  20. Demonstration of radon removal from SF6 using molecular sieves

    Science.gov (United States)

    Ezeribe, A. C.; Lynch, W.; Gregorio, R. R. Marcelo; Mckeand, J.; Scarff, A.; Spooner, N. J. C.

    2017-09-01

    The gas SF6 has become of interest as a negative ion drift gas for use in directional dark matter searches. However, as for other targets in such searches, it is important that radon contamination can be removed as this provides a source of unwanted background events. In this work we demonstrate for the first time filtration of radon from SF6 gas by using a molecular sieve. Four types of sieves from Sigma-Aldrich were investigated, namely 3Å, 4Å, 5Å and 13X. A manufactured radon source was used for the tests. This was attached to a closed loop system in which gas was flowed through the filters and a specially adapted Durridge RAD7 radon detector. In these measurements, it was found that only the 5Å type was able to significantly reduce the radon concentration without absorbing the SF6 gas. The sieve was able to reduce the initial radon concentration of 3875 ± 13 Bqm-3 in SF6 gas by 87% when cooled with dry ice. The ability of the cooled 5Å molecular sieve filter to significantly reduce radon concentration from SF6 provides a promising foundation for the construction of a radon filtration setup for future ultra-sensitive SF6 gas rare-event physics experiments.

  1. Effect of environmental conditions on radon concentration-track ...

    Indian Academy of Sciences (India)

    Abstract. In this work, the effect of environmental conditions viz., temperature (Т) and relative humidity (RH) on the track density-radon concentrations calibration factor (K) has been studied for CR-39 and LR-115 track detectors. The factor K was determined using a reference radon chamber in the National Institute for ...

  2. Intercomparison 2003 for Radon measurement services at PSI

    CERN Document Server

    Butterweck, G

    2003-01-01

    Twelve radon measurement services participated in the 2003 Radon Intercomparison Exercise performed at the Reference Laboratory for Radon Gas Activity Concentration Measurements at Paul Scherrer Institut (PSI) during March 13th to 24th, 2003. Ten of these laboratories were approved by the Swiss Federal Office of Public Health and their participation in the intercomparison exercise was a requirement to warrant quality of measurement. Radon gas detectors (etched-track and electret ionisation chambers) and instruments (ionisation chambers and electrostatic precipitation) were exposed in the PSI Radon Chamber in a reference atmosphere with an average radon gas concentration of 1950 Bqm sup - sup 3 leading to a radon gas exposure of 517 kBqhm sup - sup 3. Additional five electret-detectors of an approved measuring service were purchased by the Swiss Federal Office of Public Health for a spot check. Two of these were exposed as described above, two had an exposure of 247 kBqhm sup - sup 3 at an average radon concen...

  3. Methods of radon remediation in Finnish dwellings; Asuntojen radonkorjauksen menetelmaet

    Energy Technology Data Exchange (ETDEWEB)

    Arvela, H.

    1995-12-01

    A study was made of remedial measures taken in dwellings with high indoor radon concentrations and the results obtained. The data regarding the remedial measures taken in 400 dwellings was obtained from a questionnaire study. The mean annual average indoor radon concentration before the remedies was 1.500 Bq/m{sup 3}, the concentration exceeding in nearly every house the action level of 400 Bq/m{sup 3}. After the measures were taken the mean indoor radon concentration was 500 Bq/m{sup 3}. The resulting indoor radon concentration was less than 400 Bq/m{sup 3} in 60 percent of the dwellings. The best results were achieved using sub-slab-suction and radon well. These methods effectively decrease both the flow of radon bearing air from soil into dwellings and the radon concentration of leakage air. Typical reduction rates in radon concentration were 70-95 percent. The action level was achieved in more than 70 percent of the houses. Sealing the entry routes and improvement of the ventilation resulted typically in reduction rates of 10-50 percent. The goal of the report is to give useful information for the house owners, the do-it-yourself-mitigators, the mitigation firms and the local authorities. The report includes practical guidance, price information and examples of remedial measures. (13 refs., 10 figs., 2 tabs.).

  4. Unexpected levels and movement of radon in a large warehouse

    Energy Technology Data Exchange (ETDEWEB)

    Gammage, R.B. [Oak Ridge National Laboratory (United States); Espinosa, G. [IFUNAM, A.P. 20-364, 01000 Mexico D.F. (Mexico)

    2004-07-01

    Alpha-track detectors, used in screening for radon, identified a large warehouse with levels of radon as high as 20 p Ci/l. This circumstance was unexpected because large bay doors were left open for much of the day to admit 1 8-wheeler trucks, and exhaust fans in the roof produced good ventilation. More detailed temporal and spatial investigations of radon and air-flow patterns were made with electret chambers, Lucas-cell flow chambers, tracer gas, smoke pencils and pressure sensing micrometers. An oval-dome shaped zone of radon (>4 p Ci/L) persisted in the central region of each of four separate bays composing the warehouse. Detailed studies of air movement in the bay with the highest levels of radon showed clockwise rotation of air near the outer walls with a central dead zone. Sub slab, radon-laden air ingresses the building through expansion joints between the floor slabs to produce the measured radon. The likely source of radon is air within porous, karst bedrock that underlies much of north-central Tennessee where the warehouse is situated.

  5. RADON REDUCTION TECHNIQUES FOR DETACHED HOUSES, TECHNICAL GUIDANCE (SECOND EDITION)

    Science.gov (United States)

    This document is intended for use by State officials, radon mitigation contractors, building contractors, concerned homeowners, and other persons as an aid in the selection, design, and operation of radon reduction measurements for houses. It is the second edition of EPA's techn...

  6. Applications of a silicon photodiode detector for radon progeny measurements

    CERN Document Server

    Voytchev, M; Chambaudet, A; Georgiev, G; Iovtchev, M

    1999-01-01

    An application of our developed silicon photodiode detector for radon progeny measurements is presented in this paper. It was determined the deposition velocity for free (3.6+-0.7)x10 sup - sup 3 m s sup - sup 1 and attached (1.0+-0.5)x10 sup - sup 5 m s sup - sup 1 fraction of short living radon progeny.

  7. Investigation of the exposure to radon and progeny in the thermal spas of Loutraki (Attica-Greece): results from measurements and modelling.

    Science.gov (United States)

    Nikolopoulos, Dimitrios; Vogiannis, Efstratios; Petraki, Ermioni; Zisos, Athanasios; Louizi, Anna

    2010-01-01

    Radon and progeny ((218)Po, (214)Pb, (214)Bi and (214)Po) in thermal spas are well known radioactive pollutants identified for additional radiation burden of patients due to the activity concentration peaks which appear during bath treatment or due to drinking of waters of high radon content. This burden affects additionally the working personnel of the spas. The present paper has focused on the thermal spas of Loutraki (Attica-Greece). The aim was the investigation of the health impact for patients and working personnel due to radon and progeny. Attention has been paid to radon and progeny transient concentration peaks (for bath treatment) and to radon of thermal waters (both for bath treatment and drinking therapy). Designed experiments have been carried out, which included radon and progeny activity concentration measurements in thermal waters and ambient air. Additionally, published models for description of radon and progeny transient concentration peaks were employed. The models were based on physicochemical processes involved and employed non linear first order derivative mass balance differential equations which were solved numerically with the aid of specially developed computer codes. The collected measurements were analysed incorporating these models. Results were checked via non linear statistical tests. Predictions and measurements were found in close agreement. Non linear parameters were estimated. The models were employed for dosimetric estimations of patients and working personnel. The effective doses of patients receiving bath treatment were found low but not negligible. The corresponding doses to patients receiving potable treatment were found high but below the proposed international limits. It was found that the working personnel are exposed to considerable effective doses, however well below the acceptable limits for workers. It was concluded that treatment and working in the Loutraki spas leads to intense variations of radon and progeny and

  8. Trace and major element pollution originating from coal ash suspension and transport processes

    Energy Technology Data Exchange (ETDEWEB)

    Popovic, A.; Djordjevic, D.; Polic, P. [University of Belgrade, Belgrade (Yugoslavia). Faculty of Science, Dept. of Chemistry

    2001-07-01

    Coal ash obtained from Nikola Tesla A power plant in Obrenovac, near Belgrade, Yugoslavia, is mixed with water of the Sava river and transported to the dump. In order to assess pollution caused by leaching of some minor and major elements during ash transport through the pipeline, two sets of samples (six samples each) were subjected to a modified sequential extraction. The first set consisted of coal ash samples taken immediately after combustion, while the second set was obtained by extraction with river water, imitating the processes that occur in the pipeline. Samples were extracted consecutively with distilled water and a 1 M solution of KCl, pH 7, and the differences in extractability were compared in order to predict potential pollution. It is concluded that lead and cadmium do not present an environmental threat during and immediately after ash transport to the dump. Portions of zinc, nickel and chromium are released during the ash transport, and arsenic and manganese are released continuously. Copper and iron do not present an environmental threat due to element leaching during and immediately after the coal ash suspension and transport. On the contrary, these elements, as well as chromium, become concentrated during coal ash transport. Adsorbed portions of calcium, magnesium and potassium are also leached during coal ash transport.

  9. Trace and major element pollution originating from coal ash suspension and transport processes.

    Science.gov (United States)

    Popovic, A; Djordjevic, D; Polic, P

    2001-04-01

    Coal ash obtained by coal combustion in the "Nikola Tesla A" power plant in Obrenovac, near Belgrade, Yugoslavia, is mixed with water of the Sava river and transported to the dump. In order to assess pollution caused by leaching of some minor and major elements during ash transport through the pipeline, two sets of samples (six samples each) were subjected to a modified sequential extraction. The first set consisted of coal ash samples taken immediately after combustion, while the second set was obtained by extraction with river water, imitating the processes that occur in the pipeline. Samples were extracted consecutively with distilled water and a 1 M solution of KCl, pH 7, and the differences in extractability were compared in order to predict potential pollution. Considering concentrations of seven trace elements as well as five major elements in extracts from a total of 12 samples, it can be concluded that lead and cadmium do not present an environmental threat during and immediately after ash transport to the dump. Portions of zinc, nickel and chromium are released during the ash transport, and arsenic and manganese are released continuously. Copper and iron do not present an environmental threat due to element leaching during and immediately after the coal ash suspension and transport. On the contrary, these elements, as well as chromium, become concentrated during coal ash transport. Adsorbed portions of calcium, magnesium and potassium are also leached during coal ash transport.

  10. Spatial Evaluation Approach in the Planning Process of Transport Logistic Terminals

    Directory of Open Access Journals (Sweden)

    Mitja Pavliha

    2006-09-01

    Full Text Available The "state-of-the-art" of the present global European situationis in desperate need for a new approach to development ofurban and rural environment with an interdisciplinary approach,when introducing the elements of transport infrastructureand transport infrastructure landscape into space and environment.In order to reach a decision regarding the location of a certaintransport logistic terminal some constraints (technical andtechnological as well as financial should be considered. Aspart of the process trying to respond to these constraints, associatedprimarily with the traffic conditions at the appointed networklocations, a careful evaluation in respect to cargo flowsand infrastructure connections as well as spatial planningshould be performed.M01phological indicators, which directly and indirectly affectthe structure and the form of the transport infrastructure elements- transport logistic terminals, are extracted and presentedin the paper. At this point, the paper concludes that thelaying down and the evaluation of transport infrastructure elementsare based on two categories of morphological elements:Constructed morphological elements (all constntctionsand their elements, andNatural morphological elements (topography, climate, vegetation,etc..The presented spatial methodology deals with the interactionsbetween the constructed and natural morphological elements- the quality and the characteristics of the design areadded to both groups.Findings and projections acquired on the basis of a spatialevaluation and transport logistic analysis constitute, togetherwith financial-economic assumptions, the basis for elaboratinga business plan - a significant element in the decision-makingprocess regarding the development of a transport logistic terminal.

  11. Geographically weighted regression and geostatistical techniques to construct the geogenic radon potential map of the Lazio region: A methodological proposal for the European Atlas of Natural Radiation.

    Science.gov (United States)

    Ciotoli, G; Voltaggio, M; Tuccimei, P; Soligo, M; Pasculli, A; Beaubien, S E; Bigi, S

    2017-01-01

    In many countries, assessment programmes are carried out to identify areas where people may be exposed to high radon levels. These programmes often involve detailed mapping, followed by spatial interpolation and extrapolation of the results based on the correlation of indoor radon values with other parameters (e.g., lithology, permeability and airborne total gamma radiation) to optimise the radon hazard maps at the municipal and/or regional scale. In the present work, Geographical Weighted Regression and geostatistics are used to estimate the Geogenic Radon Potential (GRP) of the Lazio Region, assuming that the radon risk only depends on the geological and environmental characteristics of the study area. A wide geodatabase has been organised including about 8000 samples of soil-gas radon, as well as other proxy variables, such as radium and uranium content of homogeneous geological units, rock permeability, and faults and topography often associated with radon production/migration in the shallow environment. All these data have been processed in a Geographic Information System (GIS) using geospatial analysis and geostatistics to produce base thematic maps in a 1000 m × 1000 m grid format. Global Ordinary Least Squared (OLS) regression and local Geographical Weighted Regression (GWR) have been applied and compared assuming that the relationships between radon activities and the environmental variables are not spatially stationary, but vary locally according to the GRP. The spatial regression model has been elaborated considering soil-gas radon concentrations as the response variable and developing proxy variables as predictors through the use of a training dataset. Then a validation procedure was used to predict soil-gas radon values using a test dataset. Finally, the predicted values were interpolated using the kriging algorithm to obtain the GRP map of the Lazio region. The map shows some high GRP areas corresponding to the volcanic terrains (central

  12. The mathematical model of radon-222 accumulation in underground mines

    Science.gov (United States)

    Klimshin, A.

    2012-04-01

    Necessity to control underground mine air radon level arises during building and operating mines as well as auto and railway tunnels including those for metros. Calculation of underground mine air radon level can be fulfilled for estimation of potential radon danger of area for underground structure building. In this work the new mathematical model of radon accumulation in underground mines has been suggested. It takes into consideration underground mine dimensions, air exchange factor and soils ability to emanate radon. The following assumptions have been taken for model development. It is assumed that underground mine is a cylinder of length L and of base area S. Due to ventilation atmosphere air of volume activity Catm, is coming in through one cylinder base and is going out of volume activity Cind from underground mine. Diffusion radon flux is coming in through side surfaces of underground mine. The sources of this flux are radium-226 atoms distributed evenly in rock. For simplification of the task it considered possible to disregard radon emanation by loosened rock and underground waters. As a result of solution of the radon diffusion equation the following expression for calculation of radon volume activity in underground space air has been got: 2·r0 ·λv ·Catm-·l·K0(r0/l)-+D-·K1(r0/l)·C0- Cind = 2·(λ+ λv)·r0 ·l·K0 (r0/l)+ D ·K1(r0/l) . The following designations are used in this expression: Kν(r) - the second genus modified Bessel's function, C0 - equilibrium radon volume activity in soil air, l - diffusion radon length in soil, D - radon diffusion factor, r0 - radius of underground tunnel, λv - factor of air exchange. Expression found may be used for calculation of the minimum factor of necessary air exchange for ensuring safe radon levels in underground spaces. With this worked out model expected levels of radon volume activity were calculated for air in the second metro line underground spaces in the city of Yekaterinburg, Russia.

  13. Measuring radon flux across active faults: Relevance of excavating and possibility of satellite discharges

    Energy Technology Data Exchange (ETDEWEB)

    Richon, Patrick, E-mail: patrick.richon@cea.f [CEA, DAM, DIF, F-91297 Arpajon (France); Institut de Physique du Globe de Paris, Equipe Geologie des Systemes Volcaniques, 4 place Jussieu, UMR-7154 CNRS, F-75005 Paris (France); Klinger, Yann; Tapponnier, Paul [Institut de Physique du Globe de Paris, Equipe de Seismotectonique, 4 place Jussieu, UMR-7154 CNRS, F-75005 Paris (France); Li Chenxia [Institute of Geology, Chinese Earthquake Administration, P.O. Box 9803, 100029 Beijing (China); Van Der Woerd, Jerome [Institut de Physique du Globe de Strasbourg, CNRS, UMR-7516, INSU, Universite Louis Pasteur, Strasbourg I, 5 Rue Rene Descartes, F-67084 Strasbourg Cedex (France); Perrier, Frederic [Institut de Physique du Globe de Paris, Equipe de Geomagnetisme, 4 place Jussieu, UMR-7154 CNRS et Universite Paris 7 Denis-Diderot, F-75005 Paris (France)

    2010-02-15

    Searching for gas exhalation around major tectonic contacts raises important methodological issues such as the role of the superficial soil and the possible long distance transport. These effects have been studied on the Xidatan segment of the Kunlun Fault, Qinghai Province, China, using measurement of the radon-222 and carbon dioxide exhalation flux. A significant radon flux, reaching up to 538 +- 33 mBq m{sup -2} s{sup -1} was observed in a 2-3 m deep trench excavated across the fault. On the soil surface, the radon flux varied from 7 to 38 mBq m{sup -2} s{sup -1}, including on the fault trace, with an average value of 14.1 +- 1.0 mBq m{sup -2} s{sup -1}, similar to the world average. The carbon dioxide flux on the soil surface, with an average value of 12.9 +- 3.3 g m{sup -2} day{sup -1}, also remained similar to regular background values. It showed no systematic spatial variation up to a distance of 1 km from the fault, and no clear enhancement in the trench. However, a high carbon dioxide flux of 421 +- 130 g m{sup -2} day{sup -1} was observed near subvertical fractured phyllite outcrops on a hill located about 3 km north of the fault, at the boundary of the large-scale pull-apart basin associated with the fault. This high carbon dioxide flux was associated with a high radon flux of 607 +- 35 mBq m{sup -2} s{sup -1}. These preliminary results indicate that, at the fault trace, it can be important to measure gas flux at the bottom of a trench to remove superficial soil layers. In addition, gas discharges need to be investigated also at some distance from the main fault, in zones where morphotectonics features support associated secondary fractures.

  14. Flexible, inversion-based Matlab implementation of the Radon transform

    Science.gov (United States)

    Schultz, Ryan; Jeffrey Gu, Yu

    2013-03-01

    This study reviews the theory, programming designs and merits of two new Matlab-based routines for the forward and inverse Radon transform. These routines offer users flexible choices of integration path functions to take advantage of improved Radon-domain identification and isolation of seismic phases. Least-squares inversion of frequency components and judicious choices of regularization techniques enables additional noise suppression and signal enhancement in the Radon domain. The forward Radon transform routine has the added benefit of spatial interpolation for irregularly sampled data. The accuracy and applicability of these two new routines are demonstrated using data sets containing long-period SS precursors and high-frequency receiver functions. With minimal modifications these two highly portable, carefully documented Radon-transform routines could be easily adapted for a broad range of applications.

  15. Radon diffusion through multilayer earthen covers: models and simulations

    Energy Technology Data Exchange (ETDEWEB)

    Mayer, D.W.; Oster, C.A.; Nelson, R.W.; Gee, G.W.

    1981-09-01

    A capability to model and analyze the fundamental interactions that influence the diffusion of radon gas through uranium mill tailings and cover systems has been investigated. The purpose of this study is to develop the theoretical basis for modeling radon diffusion and to develop an understanding of the fundamental interactions that influence radon diffusion. This study develops the theoretical basis for modeling radon diffusion in one, two and three dimensions. The theory has been incorporated into three computer models that are used to analyze several tailings and cover configurations. This report contains a discussion of the theoretical basis for modeling radon diffusion, a discussion of the computer models used to analyze uranium mill tailings and multilayered cover systems, and presents the results that have been obtained.

  16. Comparison of seasonal variability in European domestic radon measurements

    Directory of Open Access Journals (Sweden)

    C. J. Groves-Kirkby

    2010-03-01

    Full Text Available Analysis of published data characterising seasonal variability of domestic radon concentrations in Europe and elsewhere shows significant variability between different countries and between regions where regional data is available. Comparison is facilitated by application of the Gini Coefficient methodology to reported seasonal variation data. Overall, radon-rich sedimentary strata, particularly high-porosity limestones, exhibit high seasonal variation, while radon-rich igneous lithologies demonstrate relatively constant, but somewhat higher, radon concentrations. High-variability regions include the Pennines and South Downs in England, Languedoc and Brittany in France, and especially Switzerland. Low-variability high-radon regions include the granite-rich Cornwall/Devon peninsula in England, and Auvergne and Ardennes in France, all components of the Devonian-Carboniferous Hercynian belt.

  17. Uniformity in radon exhalation from construction materials using can technique

    Energy Technology Data Exchange (ETDEWEB)

    El-Amri, E.A.; Al-Jarallah, M.I. E-mail: mibrahim@kfupm.edu.sa; Abu-Jarad, F.; Fazal-ur-Rehman

    2003-06-01

    The uniformity in radon exhalation rates for 46 tiles of granite, marble and ceramic used as construction materials were determined using 'Can Technique' employing CR-39 nuclear track detectors (NTDs). On each tile, two sealed cans, each enclosing one NTD fixed at the center of the tile surface area covered by the can, were mounted at two different locations of each individual tiles. The track production rates on the NTDs representing radon exhalation rates were measured. The radon exhalation rates from the surface of individual tiles showed uniform exhalations within the calculated uncertainties of the measured values. This makes Can Technique an alternative simple method to measure radon exhalation rates. Calibration required to convert track production rates into radon exhalation rates for the used can and NTD was done using an active technique. The correlation between the measurements by the two techniques shows a good linear correlation coefficient (0.83)

  18. Indoor radon measurements in dwellings of four Saudi Arabian cities

    Energy Technology Data Exchange (ETDEWEB)

    Al-Jarallah, M.I. E-mail: mibrahim@kfupm.edu.sa; Fazal-ur-Rehman; Abu-Jarad, F.; Al-Shukri, A

    2003-06-01

    An indoor radon survey of a total of 269 dwellings, with one dosimeter per house, distributed in four Saudi Arabian cities was carried out. The objective of this survey was to carry out indoor radon measurements of two cities in the Eastern Province, Khafji and Hafr Al-Batin and to compare this with two cities in the Western Province, Al-Madina and Taif. The survey provides additional information about indoor radon concentrations in Saudi Arabia. The results of the survey in these cities showed that the overall minimum, maximum and average radon concentration were 7,137 and 30 Bq m{sup -3}, respectively. The lowest average radon concentration (20 Bq m{sup -3}) was found in Hafr Al-Batin, while the highest average concentration was found in Khafji (40 Bq m{sup -3})

  19. Analysis of soil radon data in earthquake precursory studies

    Directory of Open Access Journals (Sweden)

    Hari Prasad Jaishi

    2014-10-01

    Full Text Available Soil radon data were recorded at two selected sites along Mat fault in Mizoram (India, which lies in the highest seismic zone in India. The study was carried out during July 2011 to May 2013 using LR-115 Type II films. Precursory changes in radon concentration were observed prior to some earthquakes that occurred around the measuring sites. Positive correlation was found between the measured radon data and the seismic activity in the region. Statistical analysis of the radon data together with the meteorological parameters was done using Multiple Regression Method. Results obtained show that the method employed was useful for removing the effect of meteorological parameters and to identify radon maxima possibly caused by seismic activity.

  20. Radon Mitigation Approach in a Laboratory Measurement Room

    Directory of Open Access Journals (Sweden)

    Patricia Blanco-Rodríguez

    2017-05-01

    Full Text Available Radon gas is the second leading cause of lung cancer, causing thousands of deaths annually. It can be a problem for people or animals in houses, workplaces, schools or any building. Therefore, its mitigation has become essential to avoid health problems and to prevent radon from interfering in radioactive measurements. This study describes the implementation of radon mitigation systems at a radioactivity laboratory in order to reduce interferences in the different works carried out. A large set of radon concentration samples is obtained from measurements at the laboratory. While several mitigation methods were taken into account, the final applied solution is explained in detail, obtaining thus very good results by reducing the radon concentration by 76%.

  1. Least-squares reverse time migration with radon preconditioning

    KAUST Repository

    Dutta, Gaurav

    2016-09-06

    We present a least-squares reverse time migration (LSRTM) method using Radon preconditioning to regularize noisy or severely undersampled data. A high resolution local radon transform is used as a change of basis for the reflectivity and sparseness constraints are applied to the inverted reflectivity in the transform domain. This reflects the prior that for each location of the subsurface the number of geological dips is limited. The forward and the adjoint mapping of the reflectivity to the local Radon domain and back are done through 3D Fourier-based discrete Radon transform operators. The sparseness is enforced by applying weights to the Radon domain components which either vary with the amplitudes of the local dips or are thresholded at given quantiles. Numerical tests on synthetic and field data validate the effectiveness of the proposed approach in producing images with improved SNR and reduced aliasing artifacts when compared with standard RTM or LSRTM.

  2. Radon Mitigation Approach in a Laboratory Measurement Room.

    Science.gov (United States)

    Blanco-Rodríguez, Patricia; Fernández-Serantes, Luis Alfonso; Otero-Pazos, Alberto; Calvo-Rolle, José Luis; de Cos Juez, Francisco Javier

    2017-05-11

    Radon gas is the second leading cause of lung cancer, causing thousands of deaths annually. It can be a problem for people or animals in houses, workplaces, schools or any building. Therefore, its mitigation has become essential to avoid health problems and to prevent radon from interfering in radioactive measurements. This study describes the implementation of radon mitigation systems at a radioactivity laboratory in order to reduce interferences in the different works carried out. A large set of radon concentration samples is obtained from measurements at the laboratory. While several mitigation methods were taken into account, the final applied solution is explained in detail, obtaining thus very good results by reducing the radon concentration by 76%.

  3. Calibration of scintillation cells for radon-222 measurements

    Science.gov (United States)

    Aakko, Kyllikki; Oksanen, Eero

    The calibration, of a radon-222 measurement system is described. The detector of the system is based on ZnS(Ag) coated scintillation cell. Evacuated cells are used for grab sample measurements of radon-222 in air. Three types of radioactive sources were used to evaluate the calibration coefficient. Standard activities were generated from commercially available solid and liquid radium-226 sources, and from a self-made radon-222 source whose activity was crosschecked by gamma spectrometric measurements. Radium-226 sources are traceable to US National Institute of Standards and Technology reference standards. Sources of error on calibration are discussed. Best accuracy was obtained by gamma spectrometrically crosschecked radon source. Considerable difficulties were encountered with the traditional method of emanating a known activity of radon-222 from a standard liquid radium-226 source. Three separate solid radium-226 sources gave results with rather large deviations. The final error weighted coefficients agree well with international intercalibration results.

  4. Potential Radon-222 Emissions from the Thorium Nitrate Stockpile

    Energy Technology Data Exchange (ETDEWEB)

    Terry, J.W.

    2003-09-04

    The Defense National Stockpile Center (DNSC), a field level activity of the Defense Logistics Agency, has stewardship of a stockpile of thorium nitrate that has been in storage for decades. The thorium nitrate stockpile was produced from 1959 to 1964 for the Atomic Energy Commission and previously has been under the control of several federal agencies. The stockpile consists of approximately 7 million pounds of thorium nitrate crystals (hydrate form) stored at two depot locations in the United States (75% by weight at Curtis Bay, Maryland, and 25% by weight at Hammond, Indiana). The material is stored in several configurations in over 21,000 drums. The U.S. Congress has declared the entire DNSC thorium nitrate stockpile to be in excess of the needs of the Department of Defense. Part of DNSC's mission is to safely manage the continued storage, future sales, and/or disposition of the thorium nitrate stockpile. Historically, DNSC has sold surplus thorium nitrate to domestic and foreign companies, but there is no demand currently for this material. Analyses conducted by Oak Ridge National Laboratory (ORNL) in 2001 demonstrated that disposition of the thorium nitrate inventory as a containerized waste, without processing, is the least complex and lowest-cost option for disposition. A characterization study was conducted in 2002 by ORNL, and it was determined that the thorium nitrate stockpile may be disposed of as low-level waste. The Nevada Test Site (NTS) was used as a case study for the disposal alternative, and special radiological analyses and waste acceptance requirements were documented. Among the special radiological considerations is the emission of {sup 220}Rn and {sup 222}Rn from buried material. NTS has a performance objective on the emissions of radon: 20 pCi m{sup -2} sec{sup -1} at the surface of the disposal facility. The radon emissions from the buried thorium nitrate stockpile have been modeled. This paper presents background information and

  5. Interacting Physical and Biological Processes Affecting Nutrient Transport Through Human Dominated Landscapes

    Science.gov (United States)

    Finlay, J. C.

    2015-12-01

    Human activities increasingly dominate biogeochemical cycles of limiting nutrients on Earth. Urban and agricultural landscapes represent the largest sources of excess nutrients that drive water quality degradation. The physical structure of both urban and agricultural watersheds has been extensively modified, and these changes have large impacts on water and nutrient transport. Despite strong physical controls over nutrient transport in human dominated landscapes, biological processes play important roles in determining the fates of both nitrogen and phosphorus. This talk uses examples from research in urban and agricultural watersheds in the Midwestern USA to illustrate interactions of physical and biological controls over nutrient cycles that have shifted nitrogen (N) and phosphorus (P) sources and cycling in unexpected ways in response to management changes. In urban watersheds, efforts to improve water quality have been hindered by legacy sources of phosphorus added to storm water through transport to drainage systems by vegetation. Similarly, reductions in field erosion in agricultural watersheds have not led to major reductions in phosphorus transport, because of continued release of biological sources of P. Where management of phosphorus has been most effective in reducing eutrophication of lakes, decreases in N removal processes have led to long term increases in N concentration and transport. Together, these examples show important roles for biological processes affecting nutrient movement in highly modified landscapes. Consideration of the downstream physical and biological responses of management changes are thus critical toward identification of actions that will most effectively reduce excess nutrients watersheds and coastal zones.

  6. Biological effects of radon in Drosophila; Efectos biologicos del radon en Drosophila

    Energy Technology Data Exchange (ETDEWEB)

    Pimentel P, A.E.; Tavera D, L.; Cruces M, M.P.; Arceo M, C.; Rosa D, M.E. de la

    1992-04-15

    The main objective of this investigation, is to study the biological effects of the Radon-222 at low dose in 'Drosophila melanogaster'. It is necessary to mention that these effects will analyze from the genetic point of view for: 1) To evaluate in which form the Radon-222 to low dose it influences in some genetic components of the adaptation in Drosophila, such as: fecundity, viability egg-adult and sex proportion. 2) To evaluate which is the genetic effect that induces the Radon to low dose by means of the SMART technique in Drosophila melanogaster, and this way to try of to identify which is the possible mechanism that causes the genetic damage to somatic level. The carried out investigation was divided in three stages: 1. Tests to the vacuum resistance. 2. Test of somatic mutation, and 3. Determination of the presence of radon daughters on the adult of Drosophila. It is necessary to point out that all the experiments were made by triplicate and in each one of them was placed detectors in preset places. Those obtained results are presented inside the 4 charts included in the present work. (Author)

  7. MODELNG RADON ENTRY INTO FLORIDA HOUSES WITH CONCRETE SLABS AND CONCRETE-BLOCK STEM WALLS, FLORIDA RADON RESEARCH PROGRAM

    Science.gov (United States)

    The report discusses results of modeling radon entry into a typical Florida house whose interior is slightly depressurized. he model predicts that the total radon entry rate is relatively low unless the soil or backfill permeability or radium content is high. ost of the factors c...

  8. Mapping of the geogenic radon potential in France to improve radon risk management: methodology and first application to region Bourgogne

    Energy Technology Data Exchange (ETDEWEB)

    Ielsch, G., E-mail: geraldine.ielsch@irsn.f [Institut de Radioprotection et de Surete Nucleaire, DEI/SARG/BRN, BP 17, 92262 Fontenay-aux-Roses cedex (France); Cushing, M.E., E-mail: edward.cushing@irsn.f [Institut de Radioprotection et de Surete Nucleaire, DEI/SARG/BRN, BP 17, 92262 Fontenay-aux-Roses cedex (France); Combes, Ph., E-mail: philippe.combes@geoter.f [GEOTER SAS, Geologie Tectonique Environnement et Risques, 3, rue Jean Monnet, 34830 Clapiers (France); Cuney, M., E-mail: michel.cuney@g2r.uhp-nancy.f [CREGU et UMR G2R 7566, Universite Henri Poincare - NANCY I, Domaine Scientifique Victor Grignard, Entree 3B, BP 70 239 - F54 506 Vandoeuvre-les-Nancy Cedex (France)

    2010-10-15

    In order to improve regulatory tools for radon risk management in France, a harmonised methodology to derive a single map of the geogenic radon potential has been developed. This approach consists of determining the capacity of the geological units to produce radon and to facilitate its transfer to the atmosphere, based on the interpretation of existing geological data. This approach is firstly based on a classification of the geological units according to their uranium (U) content, to create a radon source potential map. This initial map is then improved by taking into account the main additional parameters, such as fault lines, which control the preferential pathways of radon through the ground and which can increase the radon levels in soils. The implementation of this methodology to the whole French territory is currently in progress. We present here the results obtained in one region (Bourgogne, Massif Central) which displays significant variations of the geogenic radon potential. The map obtained leads to a more precise zoning than the scale of the existing map of radon priority areas currently based solely on administrative boundaries.

  9. Measurement of Radon Concentration in Selected Houses in Ibadan, Nigeria

    Science.gov (United States)

    Usikalu, M. R.; Olatinwo, V.; Akpochafor, M.; Aweda, M. A.; Giannini, G.; Massimo, V.

    2017-05-01

    Radon is a natural radioactive gas without colour or odour and tasteless. The World Health Organization (WHO) grouped radon as a human lung carcinogen. For this reason, there has been a lot of interest on the effects of radon exposure to people all over the world and Nigeria is no exception. The aim of this study is to investigate the radon concentration in selected houses in three local government areas of Ibadan. The indoor radon was measured in both mud and brick houses. Fifty houses were considered from the three Local government areas. A calibrated portable continuous radon monitor type (RAD7) manufactured by Durridge company was used for the measurement. A distance of 100 to 200 m was maintained between houses in all the locations. The living room was kept closed during the measurements. The mean radon concentration measured in Egbeda is 10.54 ±1.30 Bqm -3; Lagelu is 16.90 ± 6.31 Bqm -3 and Ona-Ara is 17.95 ± 1.72 Bqm -3. The mean value of the annual absorbed dose and annual effective dose for the locations in the three local government areas was 0.19 mSvy-1 and 0.48 mSvy-1 respectively. The radon concentration for location 10 in Ono-Ara local government exceeded the recommended limit. However, the overall average indoor radon concentration of the three local governments was found to be lower than the world average value of 40 Bqm -3. Hence, there is need for proper awareness about the danger of radon accumulation in dwelling places.

  10. Skylab and solar exploration. [chromosphere-corona structure, energy production and heat transport processes

    Science.gov (United States)

    Von Puttkamer, J.

    1973-01-01

    Review of some of the findings concerning solar structure, energy production, and heat transport obtained with the aid of the manned Skylab space station observatory launched on May 14, 1973. Among the topics discussed are the observation of thermonuclear fusion processes which cannot be simulated on earth, the observation of short-wave solar radiation not visible to observers on earth, and the investigation of energy-transport processes occurring in the photosphere, chromosphere, and corona. An apparent paradox is noted in that the cooler chromosphere is heating the hotter corona, seemingly in defiance of the second law of thermodynamics, thus suggesting that a nonthermal mechanism underlies the energy transport. Understanding of this nonthermal mechanism is regarded as an indispensable prerequisite for future development of plasma systems for terrestrial applications.

  11. The contribution of local and transport processes to phytoplankton biomass variability over different timescales in the Upper James River, Virginia

    Science.gov (United States)

    Qin, Qubin; Shen, Jian

    2017-09-01

    Although both local processes (photosynthesis, respiration, grazing, and settling), and transport processes (advective transport and diffusive transport) significantly affect local phytoplankton dynamics, it is difficult to separate their contributions and to investigate the relative importance of each process to the local variability of phytoplankton biomass over different timescales. A method of using the transport rate is introduced to quantify the contribution of transport processes. By combining the time-varying transport rate and high-frequency observed chlorophyll a data, we can explicitly examine the impact of local and transport processes on phytoplankton biomass over a range of timescales from hourly to annually. For the Upper James River, results show that the relative importance of local and transport processes differs on different timescales. Local processes dominate phytoplankton variability on daily to weekly timescales, whereas the contribution of transport processes increases on seasonal to annual timescales and reaches equilibrium with local processes. With the use of the transport rate and high-frequency chlorophyll a data, a method similar to the open water oxygen method for metabolism is also presented to estimate phytoplankton primary production.

  12. Virtual laboratory for the study of transport processes in surface waterflows

    Science.gov (United States)

    Aguilar, C.; Egüen, M.; Contreras, E.; Polo, M. J.

    2012-04-01

    The equations involved in the study of transport processes depend on the spatial and temporal scale of the study and according to the required level of detail can become very difficult to solve analytically. Besides, experimentation of processes with any transport phenomena involved is complex due to their natural or forced occurrence in the environment (eg. Rainfall-runoff, sediment yield, controlled and uncontrolled pollutant loadings, etc.) and the great diversity of substances and components with an specific chemical behavior. However, due to the numerous fields of application of transport phenomena (basic and applied research, hydrology and associated fluxes, sediment transport, pollutant loadings to water flows, industrial processes, soil and water quality, atmospheric emissions, legislation, etc.), realistic studies of transport processes are required. In this context, case study application, an active methodology according to the structural implications of the European Higher Education Area (EHEA), with the aid of computer tools constitute an interactive, instantaneous and flexible method with a new interplay between students and lecturers. Case studies allow the lecturer to design significant activities that generate knowledge in the students and motivates them to look for information, discuss, and be autonomous. This work presents the development of a graphical interface for the solution of different case studies for the acquisition of capacities and abilities in the autonomous apprenticeship of courses related to transport processes in Environmental Hydraulics. The interactive tool helps to develop and improve abilities in mixing and transport in surface water related courses. Thus, students clarify theoretical concepts and visualize processes with negative effects for the environment and that therefore, can only be reproduced in the laboratory or in the field under very controlled conditions and commonly with tracers instead of the real substances. The

  13. SeSBench - An initiative to benchmark reactive transport models for environmental subsurface processes

    Science.gov (United States)

    Jacques, Diederik

    2017-04-01

    As soil functions are governed by a multitude of interacting hydrological, geochemical and biological processes, simulation tools coupling mathematical models for interacting processes are needed. Coupled reactive transport models are a typical example of such coupled tools mainly focusing on hydrological and geochemical coupling (see e.g. Steefel et al., 2015). Mathematical and numerical complexity for both the tool itself or of the specific conceptual model can increase rapidly. Therefore, numerical verification of such type of models is a prerequisite for guaranteeing reliability and confidence and qualifying simulation tools and approaches for any further model application. In 2011, a first SeSBench -Subsurface Environmental Simulation Benchmarking- workshop was held in Berkeley (USA) followed by four other ones. The objective is to benchmark subsurface environmental simulation models and methods with a current focus on reactive transport processes. The final outcome was a special issue in Computational Geosciences (2015, issue 3 - Reactive transport benchmarks for subsurface environmental simulation) with a collection of 11 benchmarks. Benchmarks, proposed by the participants of the workshops, should be relevant for environmental or geo-engineering applications; the latter were mostly related to radioactive waste disposal issues - excluding benchmarks defined for pure mathematical reasons. Another important feature is the tiered approach within a benchmark with the definition of a single principle problem and different sub problems. The latter typically benchmarked individual or simplified processes (e.g. inert solute transport, simplified geochemical conceptual model) or geometries (e.g. batch or one-dimensional, homogeneous). Finally, three codes should be involved into a benchmark. The SeSBench initiative contributes to confidence building for applying reactive transport codes. Furthermore, it illustrates the use of those type of models for different

  14. Perfluoroalkyl Acid Concentrations in Blood Samples Subjected to Transportation and Processing Delay

    DEFF Research Database (Denmark)

    Bach, Cathrine Carlsen; Henriksen, Tine Brink; Bossi, Rossana

    2015-01-01

    BACKGROUND: In studies of perfluoroalkyl acids, the validity and comparability of measured concentrations may be affected by differences in the handling of biospecimens. We aimed to investigate whether measured plasma levels of perfluoroalkyl acids differed between blood samples subjected to delay...... and transportation prior to processing and samples with immediate processing and freezing. METHODS: Pregnant women recruited at Aarhus University Hospital, Denmark, (n = 88) provided paired blood samples. For each pair of samples, one was immediately processed and plasma was frozen, and the other was delayed...... and transported as whole blood before processing and freezing of plasma (similar to the Danish National Birth Cohort). We measured 12 perfluoroalkyl acids and present results for compounds with more than 50% of samples above the lower limit of quantification. RESULTS: For samples taken in the winter, relative...

  15. Transport infrastructure SEA in The Netherlands between procedure, process and content

    NARCIS (Netherlands)

    S.G. Nooteboom (Sibout)

    2007-01-01

    textabstractExperience with the EU Strategic Environmental Assessment directive is emerging. In the Netherlands it has been applied to large transport since 2005. In 2006, an evaluation of the organization of this process was done. Key lesson: infrastructure developers undertaking an environmental

  16. Transport processes of uniform and mixed sands in oscillatory sheet flow

    NARCIS (Netherlands)

    Hassan, Wael; Ribberink, Jan S.

    New experiments were carried out in the Large Oscillating Water Tunnel of WL|Delft Hydraulics (scale 1:1) using asymmetric 2nd-order Stokes waves. The main aim was to gain a better understanding of size-selective sediment transport processes under oscillatory plane-bed/sheet-flow conditions. The new

  17. Non-equilibrium reacting gas flows kinetic theory of transport and relaxation processes

    CERN Document Server

    Nagnibeda, Ekaterina; Nagnibeda, Ekaterina

    2009-01-01

    This volume develops the kinetic theory of transport phenomena and relaxation processes in the flows of reacting gas mixtures. The theory is applied to the modeling of non-equilibrium flows behind strong shock waves, in the boundary layer, and in nozzles.

  18. 23 CFR Appendix A to Part 450 - Linking the Transportation Planning and NEPA Processes

    Science.gov (United States)

    2010-04-01

    ... Transportation Planning and NEPA Processes Background and Overview: This Appendix provides additional information... rule of general applicability. For 40 years, the Congress has directed that federally-funded highway...” format, organized into three primary categories (“Procedural Issues,” “Substantive Issues,” and...

  19. Symposium on intermediate-range atmospheric-transport processes and technology assessment. [Lead Abstract

    Energy Technology Data Exchange (ETDEWEB)

    1981-10-01

    Separate abstracts were prepared for the 47 papers in this proceedings. The purpose of this meeting was to assess the state of the art of modeling atmospheric transport processes 10 to 100 km downwind of point and area sources of pollution. (KRM)

  20. Radon in Dwellings in the Republic of Kalmykia

    Energy Technology Data Exchange (ETDEWEB)

    Aakerblom, Gustav (Aakerblom och Aakerblom HP, Skaerholmen (Sweden)); German, Olga; Soederman, Ann-Louise (Swedish Radiation Safety Authority, Stockholm (Sweden)); Stamat, Ivan; Venkov, Vladimir (Research Inst. of Radiation Hygiene, St. Petersburg (Russian Federation))

    2009-02-15

    The National Radon Survey in the Republic of Kalmykia, Russian Federation during 2006-2007 was carried out in a cooperation project between the Swedish Radiation Protection Authority (SSI) and the Russian Institute of Radiation Hygiene (RIRH). In August 2006 SSI, RIRH, federal and local authorities carried out a field study in Kalmykia when radon daughter measurements (equilibrium equivalent radon concentrations in the air) and gamma radiation measurements were made in 103 buildings. Gamma spectrometry measurements were made at several sites. During the visit the cooperating parties devoted some time to the education of local authorities on radon related issues. During three months in the winter season 2006-2007, long term radon trace measurements were made in 525 randomly chosen dwellings in the Republic of Kalmykia. The radon gas activity varied between 3 and 973 Bq/m3, with a mean value of 122 Bq/m3. In 19 of a total of 835 measurement points, the radon activity exceeded the maximum permitted value in Russia of 200 Bq/m3 of EERC. The year-round radon trace measurement were made in 20 houses in Elista, the capital of the Republic of Kalmykia, for comparison with the three-month measurements. The year-round measurements showed some higher values for the radon activity, and a correction factor of 0.85 was applied. Using data on the number of people living in detached houses and apartments, and applying the radon activities measured, the number of new lung cancer cases caused by radon was calculated to be 20 to 40 of the 100 new cases reported annually. The methods of construction of the dwellings in Kalmykia is greatly influenced by the history and culture. Most of them were built after World War II and there are only a few that are newly built because of the poor economic situation and the low population growth rate in the Republic. Most people live in detached houses, one-storied with 3-5 rooms, built directly on the ground or on coquina blocks or on a cast

  1. Canadian population risk of radon induced lung cancer: a re-assessment based on the recent cross-Canada radon survey

    Science.gov (United States)

    Chen, J.; Moir, D.; Whyte, J.

    2012-01-01

    Exposure to indoor radon has been determined to be the second leading cause of lung cancer after tobacco smoking. Canadian population risk of radon induced lung cancer was assessed in 2005 with the radon distribution characteristics determined from a radon survey carried out in the late 1970s in 19 cities. In that survey, a grab sampling method was used to measure radon levels. The observed radon concentration in 14 000 Canadian homes surveyed followed a log–normal distribution with a geometric mean (GM) of 11.2 Bq m–3 and a geometric standard deviation (GSD) of 3.9. Based on the information from that survey, it was estimated that ∼10 % of lung cancers in Canada resulted from indoor radon exposure. To gain a better understanding of radon concentrations in homes across the country, a national residential radon survey was launched in April 2009. In the recent survey, long-term (3 month or longer) indoor radon measurements were made in roughly 14 000 homes in 121 health regions across Canada. The observed radon concentrations follow, as expected, a log–normal distribution with a GM of 41.9 Bq m–3 and a GSD of 2.8. Based on the more accurate radon distribution characteristics obtained from the recent cross-Canada radon survey, a re-assessment of Canadian population risk for radon induced lung cancer was undertaken. The theoretical estimates show that 16 % of lung cancer deaths among Canadians are attributable to indoor radon exposure. These results strongly suggest the ongoing need for the Canadian National Radon Program. In particular, there is a need for a focus on education and awareness by all levels of government, and in partnership with key stakeholders, to encourage Canadians to take action to reduce the risk from indoor radon exposure. PMID:22874897

  2. Comparison of Northern Ireland radon maps based on indoor radon measurements and geology with maps derived by predictive modelling of airborne radiometric and ground permeability data.

    Science.gov (United States)

    Appleton, J D; Miles, J C H; Young, M

    2011-03-15

    Publicly available information about radon potential in Northern Ireland is currently based on indoor radon results averaged over 1-km grid squares, an approach that does not take into account the geological origin of the radon. This study describes a spatially more accurate estimate of the radon potential of Northern Ireland using an integrated radon potential mapping method based on indoor radon measurements and geology that was originally developed for mapping radon potential in England and Wales. A refinement of this method was also investigated using linear regression analysis of a selection of relevant airborne and soil geochemical parameters from the Tellus Project. The most significant independent variables were found to be eU, a parameter derived from airborne gamma spectrometry measurements of radon decay products in the top layer of soil and exposed bedrock, and the permeability of the ground. The radon potential map generated from the Tellus data agrees in many respects with the map based on indoor radon data and geology but there are several areas where radon potential predicted from the airborne radiometric and permeability data is substantially lower. This under-prediction could be caused by the radon concentration being lower in the top 30 cm of the soil than at greater depth, because of the loss of radon from the surface rocks and soils to air. Copyright © 2011. Published by Elsevier B.V.

  3. Entropy production and onsager symmetry in neoclassical transport processes of toroidal plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Sugama, H.; Horton, W.

    1995-07-01

    Entropy production and Onsager symmetry in neoclassical transport processes of magnetically confined plasmas are studied in detail for general toroidal systems including nonaxisymmetric configurations. We find that the flux surface average of the entropy production defined from the linearized collision operator and the gyroangle-averaged distribution function coincides with the sum of the inner products of the thermodynamic forces and the conjugate fluxes consisting of the Pfirsch-Schlueter, banana-plateau, nonaxisymmetric parts of the neoclassical radial fluxes and the parallel current. We prove from the self-adjointness of the linearized collision operator that the Onsager symmetry is robustly valid for the neoclassical transport equations in the cases of general toroidal plasmas consisting of electrons and multi-species ions with arbitrary collision frequencies. It is shown that the Onsager symmetry holds whether or not the ambipolarity condition is used to reduce the number of the conjugate pairs of the transport fluxes and the thermodynamic forces. We also derive the full transport coefficients for the banana-plateau and nonaxisymmetric parts, separately, and investigate their symmetry properties. The nonaxisymmetric transport equations are obtained for arbitrary collision frequencies in the Pfirsch-Schlueter and plateau regimes, and it is directly confirmed that the total banana-plateau and nonaxisymmetric transport equations satisfy the Onsager symmetry. (author).

  4. Radon in indoor air of primary schools: a systematic survey to evaluate factors affecting radon concentration levels and their variability.

    Science.gov (United States)

    Bochicchio, F; Žunić, Z S; Carpentieri, C; Antignani, S; Venoso, G; Carelli, V; Cordedda, C; Veselinović, N; Tollefsen, T; Bossew, P

    2014-06-01

    In order to optimize the design of a national survey aimed to evaluate radon exposure of children in schools in Serbia, a pilot study was carried out in all the 334 primary schools of 13 municipalities of Southern Serbia. Based on data from passive measurements, rooms with annual radon concentration >300 Bq/m(3) were found in 5% of schools. The mean annual radon concentration weighted with the number of pupils is 73 Bq/m(3), 39% lower than the unweighted 119 Bq/m(3) average concentration. The actual average concentration when children are in classrooms could be substantially lower. Variability between schools (CV = 65%), between floors (CV = 24%) and between rooms at the same floor (CV = 21%) was analyzed. The impact of school location, floor, and room usage on radon concentration was also assessed (with similar results) by univariate and multivariate analyses. On average, radon concentration in schools within towns is a factor of 0.60 lower than in villages and at higher floors is a factor of 0.68 lower than ground floor. Results can be useful for other countries with similar soil and building characteristics. On average, radon concentrations are substantially higher in schools in villages than in schools located in towns (double,on average). Annual radon concentrations exceeding 300 Bq/m3 were found in 5% of primary schools (generally on ground floors of schools in villages). The considerable variability of radon concentration observed between and within floors indicates a need to monitor concentrations in several rooms for each floor. A single radon detector for each room can be used provided that the measurement error is considerable lower than variability of radon concentration between rooms. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  5. Radon as a natural tracer for underwater cave exploration.

    Science.gov (United States)

    Csondor, Katalin; Erőss, Anita; Horváth, Ákos; Szieberth, Dénes

    2017-07-01

    The Molnár János cave is one of the largest hypogenic caves of the Buda Thermal Karst (Budapest, Hungary) and mainly characterized by water-filled passages. The major outflow point of the waters of the cave system is the Boltív spring, which feeds the artificial Malom Lake. Previous radon measurements in the cave system and in the spring established the highest radon concentration (71 BqL(-1)) in the springwater. According to previous studies, the origin of radon was identified as iron-hydroxide containing biofilms, which form where there is mixing of cold and thermal waters, and these biofilms efficiently adsorb radium from the thermal water component. Since mixing of waters is responsible for the formation of the cave as well, these iron-hydroxide containing biofilms and the consequent high radon concentrations mark the active cave forming zones. Based on previous radon measurements, it is supposed that the active mixing and cave forming zone has to be close to the spring, since the highest radon concentration was measured there. Therefore radon mapping was carried out with the help of divers in order to get a spatial distribution of radon in the cave passages closest to the spring. Based on our measurements, the highest radon activity concentration (84 BqL(-1)) was found in the springwater. Based on the distribution of radon activity concentrations, direct connection was established between the spring and the István-room of the cave, which was verified by an artificial tracer. However, the distribution of radon in the cave passages shows lower concentrations (18-46 BqL(-1)) compared to the spring, therefore an additional deep inflow from hitherto unknown cave passages is assumed, from which waters with high radon content arrive to the spring. These passages are assumed to be in the active cave formation zone. This study proved that radon activity concentration distribution is a useful tool in underwater cave exploration. Copyright © 2016 Elsevier Ltd. All

  6. LRP1 Modulates APP Intraneuronal Transport and Processing in Its Monomeric and Dimeric State

    Directory of Open Access Journals (Sweden)

    Claus U. Pietrzik

    2017-04-01

    Full Text Available The low-density lipoprotein receptor-related protein 1, LRP1, interacts with APP and affects its processing. This is assumed to be mostly caused by the impact of LRP1 on APP endocytosis. More recently, also an interaction of APP and LRP1 early in the secretory pathway was reported whereat retention of LRP1 in the ER leads to decreased APP cell surface levels and in turn, to reduced Aβ secretion. Here, we extended the biochemical and immunocytochemical analyses by showing via live cell imaging analyses in primary neurons that LRP1 and APP are transported only partly in common (one third but to a higher degree in distinct fast axonal transport vesicles. Interestingly, co-expression of LRP1 and APP caused a change of APP transport velocities, indicating that LRP1 recruits APP to a specific type of fast axonal transport vesicles. In contrast lowered levels of LRP1 facilitated APP transport. We further show that monomeric and dimeric APP exhibit similar transport characteristics and that both are affected by LRP1 in a similar way, by slowing down APP anterograde transport and increasing its endocytosis rate. In line with this, a knockout of LRP1 in CHO cells and in primary neurons caused an increase of monomeric and dimeric APP surface localization and in turn accelerated shedding by meprin β and ADAM10. Notably, a choroid plexus specific LRP1 knockout caused a much higher secretion of sAPP dimers into the cerebrospinal fluid compared to sAPP monomers. Together, our data show that LRP1 functions as a sorting receptor for APP, regulating its cell surface localization and thereby its processing by ADAM10 and meprin β, with the latter exhibiting a preference for APP in its dimeric state.

  7. LRP1 Modulates APP Intraneuronal Transport and Processing in Its Monomeric and Dimeric State

    Science.gov (United States)

    Herr, Uta-Mareike; Strecker, Paul; Storck, Steffen E.; Thomas, Carolin; Rabiej, Verena; Junker, Anne; Schilling, Sandra; Schmidt, Nadine; Dowds, C. Marie; Eggert, Simone; Pietrzik, Claus U.; Kins, Stefan

    2017-01-01

    The low-density lipoprotein receptor-related protein 1, LRP1, interacts with APP and affects its processing. This is assumed to be mostly caused by the impact of LRP1 on APP endocytosis. More recently, also an interaction of APP and LRP1 early in the secretory pathway was reported whereat retention of LRP1 in the ER leads to decreased APP cell surface levels and in turn, to reduced Aβ secretion. Here, we extended the biochemical and immunocytochemical analyses by showing via live cell imaging analyses in primary neurons that LRP1 and APP are transported only partly in common (one third) but to a higher degree in distinct fast axonal transport vesicles. Interestingly, co-expression of LRP1 and APP caused a change of APP transport velocities, indicating that LRP1 recruits APP to a specific type of fast axonal transport vesicles. In contrast lowered levels of LRP1 facilitated APP transport. We further show that monomeric and dimeric APP exhibit similar transport characteristics and that both are affected by LRP1 in a similar way, by slowing down APP anterograde transport and increasing its endocytosis rate. In line with this, a knockout of LRP1 in CHO cells and in primary neurons caused an increase of monomeric and dimeric APP surface localization and in turn accelerated shedding by meprin β and ADAM10. Notably, a choroid plexus specific LRP1 knockout caused a much higher secretion of sAPP dimers into the cerebrospinal fluid compared to sAPP monomers. Together, our data show that LRP1 functions as a sorting receptor for APP, regulating its cell surface localization and thereby its processing by ADAM10 and meprin β, with the latter exhibiting a preference for APP in its dimeric state. PMID:28496400

  8. Specificity of the fluorescein transport process in Malpighian tubules of the cricket Acheta domesticus.

    Science.gov (United States)

    Neufeld, Douglas S G; Kauffman, Ross; Kurtz, Zachary

    2005-06-01

    We demonstrate the presence of an efficient, multispecific transport system for excretion of organic anions in the Malpighian tubules of the cricket Acheta domesticus using fluorescein (FL) as a model substrate. Malpighian tubules rapidly accumulated FL via a high affinity process (Km = 7.75 micromol l(-1)); uptake was completely eliminated by the prototypical organic anion transport inhibitor probenecid (1 mmol l(-1)), but not by p-aminohippuric acid (3 mmol l(-1)). FL uptake was inhibited by monocarboxylic acids at a high concentration (3 mmol l(-1)), and inhibition was more effective with an increase in the carbon chain of the monocarboxylic acid (37% inhibition by 5-carbon valeric acid, and 89% inhibition by 7-carbon caprylic acid). Likewise, tests using a series of aliphatic glutathione conjugates indicated that only the compound with the longest side-chain (decyl-glutathione) significantly inhibited FL uptake (81% inhibition). FL uptake was inhibited by a number of xenobiotics, including a plant alkaloid (quinine), herbicides (2,4-dichlorophenoxyacetic acid and 4-(2,4-dichlorophenoxy)-butyric acid), and the insecticide metabolites malathion monocarboxylic acid (MMA) and 3-phenoxybenzoic acid (PBA), suggesting that this transport system plays an active role in excretion of xenobiotics from Acheta by Malpighian tubules. HPLC quantification of MMA and PBA accumulation into Malpighian tubules verified that MMA accumulation was via a mediated transport process, but suggested that PBA accumulation was by nonspecific binding. The presence of a transport system in Malpighian tubules that handles at least one pesticide metabolite (MMA) suggests that transport processes could be a mechanism conferring resistance to xenobiotic exposure in insects.

  9. Modeling watershed-scale solute transport using an integrated, process-based hydrologic model with applications to bacterial fate and transport

    Science.gov (United States)

    Niu, Jie; Phanikumar, Mantha S.

    2015-10-01

    Distributed hydrologic models that simulate fate and transport processes at sub-daily timescales are useful tools for estimating pollutant loads exported from watersheds to lakes and oceans downstream. There has been considerable interest in the application of integrated process-based hydrologic models in recent years. While the models have been applied to address questions of water quantity and to better understand linkages between hydrology and land surface processes, routine applications of these models to address water quality issues are currently limited. In this paper, we first describe a general process-based watershed-scale solute transport modeling framework, based on an operator splitting strategy and a Lagrangian particle transport method combined with dispersion and reactions. The transport and the hydrologic modules are tightly coupled and the interactions among different hydrologic components are explicitly modeled. We test transport modules using data from plot-scale experiments and available analytical solutions for different hydrologic domains. The numerical solutions are also compared with an analytical solution for groundwater transit times with interactions between surface and subsurface flows. Finally, we demonstrate the application of the model to simulate bacterial fate and transport in the Red Cedar River watershed in Michigan and test hypotheses about sources and transport pathways. The watershed bacterial fate and transport model is expected to be useful for making near real-time predictions at marine and freshwater beaches.

  10. Transportes

    Directory of Open Access Journals (Sweden)

    Hidalgo Fernández-Cano, Amalio

    1960-01-01

    Full Text Available El movimiento de materiales dentro de la Factoría está atendido por tres principales medios de transporte, en consonancia con las características del material y de los desplazamientos. Así se han establecido: sistemas de cintas transportadoras, una red ferroviaria de ancho normal y una completa malla de caminos enlazando funcionalmente las instalaciones.

  11. Radon mitigation by depressurization of concrete walls and slabs.

    Science.gov (United States)

    Leung, J K; Tso, M Y; Hung, L C

    1999-10-01

    A special laboratory, the Radioisotope Unit Radon Analysis Laboratory, has been built for the study of radon mitigation in high-rise buildings. Reduction of radon exhalation rate from concrete walls as a result of depressurizing the interior of the wall was studied by embedding tunnels in a wall and pumping away the radon in the wall. The reduction in exhalation rate was quantified against the applied depressurization, the separation of the tunnels, the depth of the tunnel, and the thickness of the wall. Results show that radon exhalation rate from a wall embedded with tunnels can be reduced significantly by applying depressurization. For example, the radon exhalation rate from a wall of 20 cm thickness containing tunnels separated by 0.7 m can be reduced by 60% at a depressurization of 67 kPa (20 in Hg). This paper summarizes the effect of depressurization and suggests practical ways of applying the technique in radon mitigation in high-rise commercial buildings.

  12. Radon concentration measurements in the desert caves of Saudi Arabia

    Energy Technology Data Exchange (ETDEWEB)

    Al-Mustafa, Hanan [Women College, P. O. Box 838, Dammam 31113 (Saudi Arabia); Al-Jarallah, M.I. [Department of Physics, King Fahd University of Petroleum and Minerals, Dhahran 31261 (Saudi Arabia)]. E-mail: mibrahim@kfupm.edu.sa; Fazal-ur-Rehman [Department of Physics, King Fahd University of Petroleum and Minerals, Dhahran 31261 (Saudi Arabia); Abu-Jarad, F. [Radiation Protection Unit, Environmental Protection Department, Saudi Aramco P.O. Box 13027, Dhahran 31311 (Saudi Arabia)

    2005-11-15

    Beneath the harsh deserts of Saudi Arabia lie dark chambers and complex mazes filled with strange shapes and wondrous beauty. Radon concentration measurements have been carried out in the desert caves of Al-Somman Plateau in the Eastern Province of Saudi Arabia. Passive radon dosimeters, based on alpha particle etch track detectors with an inlet filter, were used in this study. A total of 59 dosimeters were placed in five caves for a period of six months. Out of 59 dosimeters, 37 could be collected for analysis. Measurements showed significant variations in radon concentrations in caves depending upon their natural ventilation. The results of the study show that the average radon concentration in the different caves ranges from 74 up to 451Bqm{sup -3}. The average radon concentration in four of the caves was low in the range 74-114Bqm{sup -3}. However, one cave showed an average radon concentration of 451Bqm{sup -3}. Radon is not a problem for tourists in the majority of caves. However, sometimes it may imply some limitation to the working time of guides.

  13. Radon and COPD mortality in the American Cancer Society Cohort

    Science.gov (United States)

    Turner, Michelle C.; Krewski, Daniel; Chen, Yue; Pope, C. Arden; Gapstur, Susan M.; Thun, Michael J.

    2012-01-01

    Although radon gas is a known cause of lung cancer, the association between residential radon and mortality from non-malignant respiratory disease has not been well characterised. The Cancer Prevention Study-II is a large prospective cohort study of nearly 1.2 million Americans recruited in 1982. Mean county-level residential radon concentrations were linked to study participants' residential address based on their ZIP code at enrolment (mean±sd 53.5±38.0 Bq·m−3). Cox proportional hazards regression models were used to estimate adjusted hazard ratios (HR) and 95% confidence intervals (CI) for non-malignant respiratory disease mortality associated with radon concentrations. After necessary exclusions, a total of 811,961 participants in 2,754 counties were included in the analysis. Throughout 2006, there were a total of 28,300 non-malignant respiratory disease deaths. Radon was significantly associated with chronic obstructive pulmonary disease (COPD) mortality (HR per 100 Bq·m−3 1.13, 95% CI 1.05–1.21). There was a significant positive linear trend in COPD mortality with increasing categories of radon concentrations (pradon may increase COPD mortality. Further research is needed to confirm this finding and to better understand possible complex inter-relationships between radon, COPD and lung cancer. PMID:22005921

  14. Radon Release and Its Simulated Effect on Radiation Doses.

    Science.gov (United States)

    Orabi, Momen

    2017-03-01

    One of the main factors that affect the uncertainty in calculating the gamma-radiation absorbed dose rate inside a room is the variation in the degree of secular equilibrium of the considered radioactive series. A component of this factor, considered in this paper, is the release of radon (Rn) from building materials to the living space of the room. This release takes place through different steps. These steps are represented and mathematically formulated. The diffusion of radon inside the material is described by Fick's second law. Some of the factors affecting the radon release rate (e.g. covering walls, moisture, structure of the building materials, etc.) are discussed. This scheme is used to study the impact of radon release on the gamma-radiation absorbed dose rate inside a room. The investigation is carried out by exploiting the MCNP simulation software. Different building materials are considered with different radon release rates. Special care is given to Rn due to its relatively higher half-life and higher indoor concentration than the other radon isotopes. The results of the presented model show that the radon release is of a significant impact in some building materials.

  15. Occurrence of radon in the Polish underground tourist routes

    Directory of Open Access Journals (Sweden)

    Jerzy Olszewski

    2015-08-01

    Full Text Available Background: There are about 200 underground tourist routes in Poland. There are caves, mines or underground structures. This paper presents the results of the research intended to identify the extent of the occurrence of radon concentrations in underground areas of tourist routes. Material and Methods: We conducted the measurement of periodic concentrations of radon (1–2 months in the summer using type Tastrak trace detectors. We determined the average concentrations of radon in air in 66 underground tourist routes in Poland. Results: The research results comprise 259 determinations of average radon concentrations in 66 routes. The arithmetic average of the results was 1610 Bqm–3, and the maximum measured concentration was over 20 000 Bqm–3. The minimum concentration was 100 Bqm–3 (threshold method considering the arithmetic average of the measurements. It was found that in 67% of the routes, the average concentration of radon has exceeded 300 Bqm–3 and in 22 underground routes it exceeded 1000 Bqm–3. Conclusions: Radon which occurs in many Polish underground tourist routes may be an organizational, legal and health problem. It is necessary to develop a program of measures to reduce radon concentrations in underground routes, especially routes located in the former mines. Med Pr 2015;66(4:557–563

  16. Long term performance of different radon remedial methods in Sweden

    CERN Document Server

    Clavensjoe, B

    2002-01-01

    The object of this project was to investigate the long time effectiveness of different radon remedial methods. The ten years project started 1991. From start the investigation comprised of 105 dwellings (91 single-family houses and 14 flats in multi-family buildings). In all of the dwellings remedial measures were carried out in the eighties. Before and immediately after the reduction the local measured the radon concentrations. New measurements of the radon concentrations have been made every third year; in 1991, 1994, 1997 and in 2000. Twelve different radon remedial methods and method combinations were used. The radon sources were building materials as well as sub-soils. In all of the dwellings the radon concentrations were measured by nuclear track films during 3 months (January-March) measurements and in half of them the air change rates by passive tracer gas methods. The results of the 2000 and the 1991 (within brackets) studies showed that the radon concentration was up to 200 Bq/m sup 3 in 54 (54) sin...

  17. Enhanced radon emission in natural CO2 flows in Campo de Calatrava region (central Spain)

    OpenAIRE

    Elio Medina, Javier de; Ortega Romero, Marcelo Fabián; Mazadiego Martínez, Luis Felipe; Grandia, Fidel; Gasparini, Andrea; Caballero, Juan; Sáinz, Álvaro

    2014-01-01

    Activity of radon gas in natural soils is commonly low (in the order of few thousands of Bq·m-3) due to the fast decay (half-life= 3.8 days in the case of 222Rn) that prevents accumulation in soil pores. Exceptionally, high Rn soil activity (up to 430 KBq·m-3) is found around point sources of deep CO2 fluxes. These fluxes allow the transport of trace gases (including Rn) to long distances in the geosphere leading to a potential hazard as Rn accumulation in buildings. CO2 degassing is common i...

  18. Graphene transport properties upon exposure to PMMA processing and heat treatments

    DEFF Research Database (Denmark)

    Gammelgaard, Lene; Caridad, Jose; Cagliani, Alberto

    2014-01-01

    The evolution of graphene's electrical transport properties due to processing with the polymer polymethyl methacrylate (PMMA) and heat are examined in this study. The use of stencil (shadow mask) lithography enables fabrication of graphene devices without the usage of polymers, chemicals or heat......, allowing us to measure the evolution of the electrical transport properties during individual processing steps from the initial as-exfoliated to the PMMA-processed graphene. Heating generally promotes the conformation of graphene to SiO2 and is found to play a major role for the electrical properties...... that flakes conforming poorly to the substrate will have a higher carrier mobility which will however be reduced as heat treatment enhance the conformation. We finally show the electrical properties of graphene to be reversible upon heat treatments in air up to 200°C....

  19. Analytical solutions for transport processes fluid mechanics, heat and mass transfer

    CERN Document Server

    Brenn, Günter

    2017-01-01

    This book provides analytical solutions to a number of classical problems in transport processes, i.e. in fluid mechanics, heat and mass transfer. Expanding computing power and more efficient numerical methods have increased the importance of computational tools. However, the interpretation of these results is often difficult and the computational results need to be tested against the analytical results, making analytical solutions a valuable commodity. Furthermore, analytical solutions for transport processes provide a much deeper understanding of the physical phenomena involved in a given process than do corresponding numerical solutions. Though this book primarily addresses the needs of researchers and practitioners, it may also be beneficial for graduate students just entering the field. .

  20. A biophysical analysis of mitochondrial movement: differences between transport in neuronal cell bodies versus processes.

    Science.gov (United States)

    Narayanareddy, Babu Reddy Janakaloti; Vartiainen, Suvi; Hariri, Neema; O'Dowd, Diane K; Gross, Steven P

    2014-07-01

    There is an increasing interest in factors that can impede cargo transport by molecular motors inside the cell. Although potentially relevant (Yi JY, Ori-McKenney KM, McKenney RJ, Vershinin M, Gross SP, Vallee RB. High-resolution imaging reveals indirect coordination of opposite motors and a role for LIS1 in high-load axonal transport. J Cell Biol 2011;195:193-201), the importance of cargo size and subcellular location has received relatively little attention. Here we address these questions taking advantage of the fact that mitochondria - a common cargo - in Drosophila neurons exhibit a wide distribution of sizes. In addition, the mitochondria can be genetically marked with green fluorescent protein (GFP) making it possible to visualize and compare their movement in the cell bodies and in the processes of living cells. Using total internal reflection microscopy coupled with particle tracking and analysis, we quantified the transport properties of GFP-positive mitochondria as a function of their size and location. In neuronal cell bodies, we find little evidence for significant opposition to motion, consistent with a previous study on lipid droplets (Shubeita GT, Tran SL, Xu J, Vershinin M, Cermelli S, Cotton SL, Welte MA, Gross SP. Consequences of motor copy number on the intracellular transport of kinesin-1-driven lipid droplets. Cell 2008;135:1098-1107). However, in the processes, we observe an inverse relationship between the mitochondrial size and velocity and the run distances. This can be ameliorated via hypotonic treatment to increase process size, suggesting that motor-mediated movement is impeded in this more-confined environment. Interestingly, we also observe local mitochondrial accumulations in processes but not in cell bodies. Such accumulations do not completely block the transport but do increase the probability of mitochondria-mitochondria interactions. They are thus particularly interesting in relation to mitochondrial exchange of elements.