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Abstract  

We have measured the variation of atmospheric pressure and of 222Rn activity concentration in the air of a wine cellar with an AlphaGAURD type ionization chamber radon monitor. We have found that the 222Rn activity concentration varies inversely with pressure. To explain this behavior we have done model calculations. We have compared the results of model calculations with the results of experimental measurements, and we have found that the model is capable to reproduce some part of the variation of 222Rn activity concentration.

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Journal of Radioanalytical and Nuclear Chemistry
Authors: K. Ioannides, C. Papachristodoulou, D. Karamanis, K. Stamoulis, and T. Mertzimekis

Abstract  

The concentration of radon (222Rn) was measured in the soil near the ground surface, using CR/39 solid state nuclear track detectors. The measurements were carried out in PVC tubes at 0.25 m intervals up to 1.25 m. The detectors were etched in 7N NaOH solutions at 80°C. The -tracks from radon's decay were counted using a microscope. A microscope-camera-computer system developed for automatic counting was also used. The results provide evidence for the non-diffusive transport of radon in soils. A transport length of (46.9±3.2) cm was estimated for radon transport near ground surface. Also the variation of soil's radon concentration was correlate to humidity and atmospheric pressure.

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Abstract  

The activity concentrations of the Ra isotopes, 226Ra and 228Ra, as well as of 222Rn were measured in Austrian tap waters. Rn was extracted into a mineral oil cocktail not miscible with water and measured by liquid scintillation counting using pulse-shape analysis for α/β-separation. Ra isotopes were co-precipitated with BaSO4 or concentrated by filtration through an element specific filter. EDTA solution was used to redissolve the precipitate as well as to release the Ra from the filter. After mixing with a cocktail, the EDTA solution was measured by liquid scintillation counting, too. From our results the effective ingestion doses for adults and 3 months old babies were calculated.

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Abstract  

The adsorption coefficient is the fundamental parameter characterizing activated charcoal"s ability to adsorb 222Rn. The adsorption coefficient is determined for 222Rn activated charcoal detectors. In addition, a diffusion and adsorption model is developed for the transport of 222Rn in a porous bed of activated charcoal. These processes can be described by parabolic second order differential equation. The equation is numerically solved using the finite differences method. With this model, the 222Rn activity adsorbed in the detector is calculated for diverse situations.

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Abstract  

Simultaneous measurements of the222Rn concentration in the outdoor atmosphere of Bratislava and in the soil air over one year period have been made. Daily and seasonal variations of the222Rn concentration in both media were found. Some attributes of these variations as well as methods of measurements are presented in this work.

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Abstract  

222Rn concentrations along the seismic active area (some distinct in East Anatolian Active Fault System (EAFS), Turkey) were determined by using passive and active (prompt) methods including CR-39 and Markus-10, respectively. It was observed that the changing of 222Rn concentration along the fault lines, crossing the main East Anatolian Fault Line, has shown similar characteristics for both methods. The mean 222Rn concentrations were found to be between 1.2 and 3.6 kBq·m−3 and, 2 and 70 kBq·m−3 by using passive and prompt methods, respectively. Nevertheless, some measured terrestrial gamma-radiation dose rate in the same area has weak positive correlation to 222Rn concentration. Terrestrial gamma-dose rate at 1 m above the ground in the same sampling point, as for 222Rn concentration measurement were made, varied from 8.5 to 10.6 μR·h−1.

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Summary  

Measurement of 222Rn emanation from building components is now mandatory by European law. This implies formulation in terms of basic parameters and design of a routine control procedure. Both are presented here.

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Abstract  

Continuous measurements of atmospheric222Rn were made for the past three years by the Environmental Measurements Laboratory (EML) at the Atmosphere/Ocean Chemistry Experiment site located at Tudor Hill, Bermuda and at the National Oceanic and Atmospheric Administration/Climate Monitoring and Diagnostics Laboratory Mauna Loa Observatory. The222Rn analyzer is based on the two-filter tube method. At the Bermuda site, monthly median222Rn concentration range from 50 to 700 mBq m–3, and the concentrations vary seasonally, with a maximum in the winter and a minimum in the summer. The concentrations are significantly elevated when local winds traverse the island. At MLO, monthly median222Rn concentrations range from 100 mBq m–3 during the fall months to 400 mBq m–3 during the spring months. The springtime maximum values correspond to periods of rapid transport in the free troposphere from the Asian continent, corroborated by backward air mass trajectories. The222Rn data are also used to help decipher local daily upslope/downslope conditions present at MLO. This study illustrates the value of atmospheric222Rn monitoring, when screened through the filter of local meteorology, in studying the transport of continental air to the oceans, as well as the dynamics of local meteorological effects.

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Abstract  

Liquid scintillation counting (LSC) method has been used for the measurement of 222Rn in mineral water samples under a pilot project for the first surveillance in Iran. Low level background LSC counter Quantulus and pulse-shape analysis method have been employed. The concentration of 222Rn found in mineral waters of the studied areas ranges from about 1 to 75 Bq/l. The best lower limit of detection obtained with the applied technique was 0.069 Bq/l for a counting time in the range of 236–296 minutes.

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Abstract  

The effect of cigarette smoke in air on the increase of the measured equivalent volume activity of222Rn is demonstrated. After introduction of the smoke from one cigarette into 1 m3 of air, this value increased up to ten times as shown by the method of sucking air through a filter.

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