Informacja

Drogi użytkowniku, aplikacja do prawidłowego działania wymaga obsługi JavaScript. Proszę włącz obsługę JavaScript w Twojej przeglądarce.

Wyszukujesz frazę "Rn-222" wg kryterium: Temat


Wyświetlanie 1-4 z 4
Tytuł:
Soil heat flux and air temperature as factors of radon (Rn-222) concentration in the near-ground air layer
Autorzy:
Podstawczyńska, A.
Pawlak, W.
Powiązania:
https://bibliotekanauki.pl/articles/971505.pdf
Data publikacji:
2016
Wydawca:
Instytut Chemii i Techniki Jądrowej
Tematy:
air temperature
Central Poland
exponential function
Rn-222
soil heat flux
Opis:
A unique, highly time-resolved, and synchronous three-year dataset of near-surface atmospheric radon-222 as well as soil heat flux and air temperature measurements at two sites (rural and urban) in Central Poland are investigated. The recognition of temporal variability of Rn-222 and selected meteorological variables in the urban and rural areas served to create two statistical models for estimation of this radionuclide concentration at 2 m a.g.l. The description of the relationships between the variables for individual months was established on the basis of an exponential function and an exponential function with time derivative of predictor to account for the hysteresis issue. The model with time derivative provided better results. The weakest fitting of modelled data to empirical ones is observed for the winter months. During subsequent seasons, air temperature as well as QG-driven (soil heat flux) models exhibited very high agreement with the empirical data (MBE, RMSE, MAE, and ‘index of agreement’ by Willmott were used to evaluate the models). A restriction in the use of QG for Rn-222 concentration was observed only in winter in the case of snow cover occurrence, which reduces the daily QG variability. A unique, highly time-resolved, and synchronous three-year dataset of near-surface atmospheric radon-222 as well as soil heat flux and air temperature measurements at two sites (rural and urban) in Central Poland are investigated. The recognition of temporal variability of Rn-222 and selected meteorological variables in the urban and rural areas served to create two statistical models for estimation of this radionuclide concentration at 2 m a.g.l. The description of the relationships between the variables for individual months was established on the basis of an exponential function and an exponential function with time derivative of predictor to account for the hysteresis issue. The model with time derivative provided better results. The weakest fitting of modelled data to empirical ones is observed for the winter months. During subsequent seasons, air temperature as well as QG-driven (soil heat flux) models exhibited very high agreement with the empirical data (MBE, RMSE, MAE, and ‘index of agreement’ by Willmott were used to evaluate the models). A restriction in the use of QG for Rn-222 concentration was observed only in winter in the case of snow cover occurrence, which reduces the daily QG variability.
Źródło:
Nukleonika; 2016, 61, 3; 231-237
0029-5922
1508-5791
Pojawia się w:
Nukleonika
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The characteristics of radon and thoron concentration from soil gas in Shenzhen City of Southern China
Autorzy:
Wang, N.
Zheng, L.
Chu, X.
Li, S.
Yan, S.
Powiązania:
https://bibliotekanauki.pl/articles/148789.pdf
Data publikacji:
2016
Wydawca:
Instytut Chemii i Techniki Jądrowej
Tematy:
222Rn/220Rn
soil gas
radon mapping
China
Opis:
Radon (222Rn) and thoron (220Rn) from soil gas are very significant factors that can affect the indoor radon level in the first floor or in the basement. China is one of the countries with the highest thorium content in the world. Therefore, it is very significant to study 222Rn/220Rn concentration in the soil in Shenzhen City (SC). A 222Rn/220Rn survey was performed using a portable radon monitor (model RAD7) at 69 sites, covered a total area of 1800 km2 in 2013 to get the original data for radon risk estimation in SC. The average values of 222Rn and 220Rn concentration of soil gas of the total 69 locations are 86 ± 72 kBq•m–3 and 118 ± 85 kBq•m–3, respectively. 222Rn/220Rn concentrations are related to geological lithology. 222Rn concentrations vary from 40 to 370 kBq•m–3 and from 15 to 118 kBq•m–3 in weathered granite products and sediments, respectively, while 220Rn concentrations are from 103 to 435 kBq•m–3 and 2.2 to 96 kBq•m–3. The higher 220Rn values were mainly observed at the sites covered by the weathered granite products. Comparing with the areas of high 222Rn concentration, the areas of high 220Rn values are larger. The distribution of 222Rn concentration in the vertical direction displays an exponential distribution mode, but there is no rule of 220Rn concentration. The investigation suggests that people should pay attention to 220Rn contribution in the radon mapping of SC, as well as in the indoor radon survey.
Źródło:
Nukleonika; 2016, 61, 3; 315-319
0029-5922
1508-5791
Pojawia się w:
Nukleonika
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Parameter sensitivity analysis of the theoretical model of a CR-39-based direct 222Rn/220Rn progeny monitor
Autorzy:
Hu, Jun
Hosoda, Masahiro
Tokonami, Shinji
Powiązania:
https://bibliotekanauki.pl/articles/148634.pdf
Data publikacji:
2020
Wydawca:
Instytut Chemii i Techniki Jądrowej
Tematy:
222Rn
220Rn progeny
parameter sensitivity analysis
theoretical model
Opis:
The deposition-based direct indoor 222Rn and 220Rn progeny measurement techniques are mostly affected by the indoor environmental conditions, such as the ventilation, concentration of condensation nuclei, and reactions with the structure and its furnishings. In this study, a theoretical model of a direct 222Rn and 220Rn progeny monitor based on allyl diglycol carbonate (ADC or CR-39) was established to analyse the factors that influence the detection process by using the parameter sensitivity analysis. The aerosol parameters contributed the highest to the variance, followed by the aerodynamic parameters. With respect to the result of the Spearman’s correlation analysis, the aerosol-related and the room-related parameters are positive, whereas the aerodynamic parameters – which affect the turbulence of indoor deposition – are negative. It means that both the attachment process and the deposition process of 222Rn and 220Rn progenies are important to the performance of the progeny monitor.
Źródło:
Nukleonika; 2020, 65, 2; 95-98
0029-5922
1508-5791
Pojawia się w:
Nukleonika
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Seasonal and diurnal variation of outdoor radon (222Rn) concentrations in urban and rural area with reference to meteorological conditions
Autorzy:
Podstawczyńska, A.
Kozak, K.
Pawlak, W.
Mazur, J.
Powiązania:
https://bibliotekanauki.pl/articles/148896.pdf
Data publikacji:
2010
Wydawca:
Instytut Chemii i Techniki Jądrowej
Tematy:
outdoor radon (222Rn) concentration
urban climate
seasonal variation
diurnal variation
meteorological parameters
Opis:
The objective of the study was to investigate temporal variability of outdoor radon (222Rn) concentration registered in the center of Łódź (urban station), at Ciosny (rural station) and Kraków (suburban station) in relation to meteorological parameters (i.e. air temperature, temperature vertical gradient, wind speed, soil heat flux, volumetric water content in soil) with special consideration of urban-rural differences. Continuous measurements of 222Rn concentration (at 60 min intervals) were performed at a height of 2 m above the ground using AlphaGUARDŽ PQ2000PRO (ionization chamber) from January 2008 to May 2009. 222Rn levels were characterized by a diurnal cycle with an early morning maximum and a minimum in the afternoon. The well-marked 24 h pattern of radon concentration occurred in summer at anticyclonic weather with cloudless sky, light wind and large diurnal temperature ranges. The urban measurement site was characterized by the lowest atmospheric 222Rn concentration and an urban-rural differences of radon levels increased from winter to summer and during the nighttime periods. The maximum contrasts of 222Rn levels between Łódź and Ciosny, reaching – 30 Bqźm–3, were registered in June and July during the urban heat island (UHI) phenomenon (a positive thermal anomaly of a city if compared to rural area) and strong thermal inversion near the ground in the rural area.
Źródło:
Nukleonika; 2010, 55, 4; 543-547
0029-5922
1508-5791
Pojawia się w:
Nukleonika
Dostawca treści:
Biblioteka Nauki
Artykuł
    Wyświetlanie 1-4 z 4

    Ta witryna wykorzystuje pliki cookies do przechowywania informacji na Twoim komputerze. Pliki cookies stosujemy w celu świadczenia usług na najwyższym poziomie, w tym w sposób dostosowany do indywidualnych potrzeb. Korzystanie z witryny bez zmiany ustawień dotyczących cookies oznacza, że będą one zamieszczane w Twoim komputerze. W każdym momencie możesz dokonać zmiany ustawień dotyczących cookies