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EN
The radioactivity levels of natural radionuclides 226Ra, 232Th, and 40K in the rocks of Dakshina Kannada region of southern India were measured by NaI (Tl) gamma-ray spectrometer. The specific activities of 226Ra, 232Th, and 40K ranged from 4.2±0.4 to 74.5±1.7 Bq kg−1, 14.5±0.7 to 83.5±1.6 Bq kg−1, and 172±3 to 964±7 Bq kg−1 with the mean of 25.1±1.0 Bq kg−1, 36.1±1.0 Bq kg−1, and 502±5.0 Bq kg−1, respectively. The normality of the frequency distribution curves of 226Ra, 232Th, and 40K was tested using the Kolmogorov–Smirnov test. The radiological hazard indices were computed from the measured activity concentration of natural radionuclides in rocks and these were found to be within acceptable levels. To investigate the sources of radioactivity, the minerals involved in the rocks were detected using XRD and FTIR. The mineralogical studies reveal that the principal sources of gamma radiation in the study area are 232Th-rich phosphates and 40K-bearing feldspars.
EN
Jamske Pleso lake is one of almost 200 lakes located in the Tatra Mountains. This post glacial water reservoir is set on a strictly protected area. In this work, sediment samples taken from Jamske Pleso Lake were analysed for radioactivity of natural 226Ra, 210Po, 210Pb and artificial 137Cs. The sediment core was taken by use of Limnos corer. After preparation of the physical sample, gamma measurements were executed in hermetically closed vessels. A preliminary study showed that concentration of natural radionuclides is in typical values for lakes located in this area. An elevated concentration of 226Ra (mean 57 ± 29 Bq ∙ kg–1) is an effect of uranium rich bedrock of the lake. Radioactivity of 137Cs is close to that reported in other Tatras lakes. Using 137Cs as an indicator allowed a preliminary estimate of the depth of the sediments deposited in 1960s.
PL
Jamski Staw (słow. Jamské Pleso) to jeden spośród niemal 200 tatrzańskich stawów. Ten zbiornik o charakterze polodowcowym położony jest na terenie objętym ochroną ścisłą. Celem niniejszej pracy było wyznaczenie poziomu radioaktywności naturalnych 226Ra, 210Po i 210Pb oraz sztucznego 137Cs w profilach osadów dennych pobranych z Jamskiego Stawu. Profile rdzeniowe osadów pobrano przy pomocy czerpaka firmy Limnos. Po wstępnej obróbce próbek i umieszczeniu ich w szczelnych naczyniach pomiarowych poddano je analizie z wykorzystaniem spektrometru promieniowania gamma. Wstępne wyniki pokazały, że radioaktywność naturalnych izotopów jest na zbliżonym poziomie, do notowanej w innych stawach tego regionu. Podniesiony poziom radioaktywności 226Ra (średnia 57 ± 29 Bq ∙ kg–1) jest związany z zawierającym uran, granitowym trzonem podłożem skalnym jeziora. Radioaktywność 137Cs jest na podobnym poziomie co w innych stawach tatrzańskich. Wykorzystanie 137Cs jako znacznika czasu pozwoliło na wstępną identyfikację warstw osadów nagromadzonych w latach 60. XX wieku.
EN
The paper presents, the chemical composition and the activity concentrations of natural radionuclides (238U, 234U,226Ra and 228Ra) in selected therapeutic mineral waters from: Krynica-Zdrój (Zuber I, Zuber II and Słotwinka), Rabka-Zdrój (Krakus, Warzelnia and Rabka IG-2), Iwonicz-Zdrój (Elin 7 and Emma 7), Klimkówka (Klimkówka 27) and Lubatówka (Lubatówka 12). The analyses were carried outfor water samples collected twice in 2008 and in 2016. The analyzed waters are used mainly for crenotherapy and therapeutic bathing. Some waters are also bottled and used for production of cosmetics and medicinal waters. The measured uranium activity concentrations in the studied groundwater were very low, below 3 mBq/dm3 and 11 mBq/dm3 for 238U and 234U, respectively. In the case of radium isotopes (226Ra and 228Ra), their activity concentrations varied in a wide range from ca. 150 to ca. 1500 mBq/dm3. The total mineralization of the analyzed waters variedfrom 3.5 to ca. 24 g/dm3. A significant variation of both chemical composition and radium concentrations were observed in the water from Warzelnia intake. For the remaining waters, variation of 226Ra and 228Ra concentrations was observed in three (Zuber I, Słotwinka, Emma 7), and six intakes (Zuber I, Słotwinka, Krakus, Klimkówka 27, Emma 7, Elin 7), respectively.
EN
The field radiometric and laboratory measurements were performed at the Sin Quyen copper deposit in North Vietnam. The field gamma-ray spectrometry indicated the concentration of uranium ranging from 5.5 to 87 ppm, thorium from 5.6 to 33.2 ppm, and potassium from 0.3 to 4.7%. The measured dose rates ranged from 115 to 582 nGy/h, the highest doses being at the copper ore. Concentrations in the solid samples were in the range of 20-1700 Bq/kg for uranium, 20-92.7 Bq/kg for thorium, and 7-1345 Bq/kg for potassium. The calculated doses were from 22 to 896 nGy/h; both measured and calculated dose rates are mostly related to uranium. Concentrations of radium in water samples were below 0.17 Bq/L. Uranium in water samples was significantly higher than the hydrogeological background; the maximum of 13 Bq/L was at the waste zone pool, but neither radium nor uranium were present in tap water. Radon concentration in the dwelling air was from 42 to 278 Bq/m3 for 222 Rn and from 8 to 193 Bq/m3 for 220Rn. The estimated committed dose rates were principally related to 222Rn concentration and ranged from 1.1 to 8.1 mSv/y.
EN
The energy released in a spontaneous decay process of natural radionuclides is the main source of the total radiation dose to human beings. Natural radionuclides are widely distributed in soil, rocks, air, and groundwater. In present investigation, the analysis of terrestrial radionuclides such as 226Ra, 232Th, and 40K in soil and sand of Chattarpur area of southeastern coast of Odisha has been carried out using NaI(Tl) gamma ray detector. The higher activity concentrations of naturally occurring radionuclides have been reported from the study area. The gamma radiationdose originating from the terrestrial radionuclides was found to vary from 95 to 1813 nGy/h with an average of 700 nGy/h. This study is important to generate a baseline data of radiation exposure in the area. Health hazard effects due to natural radiation exposure are discussed in details.
EN
A simple procedure using α and γ spectrometry for the determination of natural radionuclides in two Polish geothermal water samples from Mszczonów and Cieplice, as well as in deep well groundwater from the city of Łódź, was described. The 222Rn radionuclide was directly extracted from 10 cm3 water samples to a scintillator solution placed in scintillation vials and determined by an liquid scintillation (LSC) technique with α/β separation. The activity concentrations of three radium nuclides: 228Ra(228Ac), 226Ra(222Rn), 224Ra, as well as 210Pb and 228Th were measured by γ spectrometry with an HPGe detector after their preconcentration on hydrated MnO2. 210Po was deposited on a silver disc from dissolved MnO2 precipitate after γ-spectrometry analysis and measured by α spectrometry. The concentration of 210Pb in the examined samples was below the detection limit of the method (< 6.2 mBq/dm3), whereas activity of its decay product 210Po was in the range 0.35–1.4 mBq/dm3. Higher activities of 228Ra (46.7 mBq/dm3), 226Ra (67.8 mBq/dm3) and 224Ra (22.4 mBq/dm3) were observed for the deep well water in Łódź in comparison to those for geothermal water samples from Cieplice and Mszczonów. However, concentrations of all the measured radionuclides were below World Health Organization (WHO) reference activities (0.1 Bq/dm3 for 228Ra and 1 Bq/dm3 for 226Ra and 226Ra).
EN
Activities of the main radionuclides from the 238U and 232Th series in the Uniejów geothermal water were determined by combining liquid scintillation counting with a/b separation and g-spectrometry methods. The 222Rn and 226Ra activities were measured after extraction of radon from 10 ml water samples to 10 ml of an Ultima Gold F scintillation cocktail directly in 22 ml scintillation vials. The samples were counted in a new generation portable liquid scintillation counter, Betascout, without separation of the phases over the period of 30 days after extraction. The average values of the specific activities were equal to 2.95 and 0.64 Bq/dm3 for 222Rn and 226Ra, respectively. The 210Po radionuclide before counting was preconcentrated from 1 dm3 water samples on hydrated manganese oxide and deposited on silver discs. The discs were immersed in 10 ml of the scintillator and their activity was measured also by the same method. The average 210Po concentration was 0.052 Bq/dm3. Activity of the remaining radionuclides was determined by g-spectrometry after their preconcentration on hydrated manganese oxides from 10 dm3 samples. The activities of two radium radionuclides, 224Ra and 226Ra, can be calculated from their basic gamma-lines, whereas 228Ra can be determined from its decay product - 228Ac, and were equal to 0.40, 0.65 and 0.58 Bq/dm3, respectively. The activities of 210Pb and 238U (234Th) were below the detection limit of the method equal to 0.03 Bq/dm3. Based upon the obtained results, it can be concluded that there are not any radiological restrictions for using this water as a heat source or for balneological purposes. However, it cannot be used as drinking water, because the calculated committed effective dose from its one year consumption exceeds the WHO recommended value of 0.1 mSv.
PL
Oszacowano wartości współczynników transferu naturalnych radionuklidów: [wzory] z gleb piaszczystych do roślinności zalegających w północno-wschodniej Polsce. Zawartość radionuklidów w szacie roślinnej oznaczono metodą gamma spektrometrii. Znaleziono istotne korelacje między wartościami wspołczynników transferu i dominującymi parametrami gleb.
EN
Transfer of natural radionuclides: [formulas] from sandy soils to plant in northeastern Poland was evaluated. The content of radionuclides was determined by gamma spectrometry. Some correlation between transfer coefficient and dominating parameters of soils have been found.
PL
W pracy przedstawiono wyniki badań dotyczących zawartości radioaktywnego potasu [wzór], ołowiu [wzór], bizmutu [wzór], aktynu [wzór] i talu [wzór] w glebach północno-wschodniej Polski. Zawartości badanych radionuklidów wykazywały duże zróżnicowanie nawiązujące do wykształcenia litologicznego gleb. Stwierdzono istotne współzależności między kumulacją [wzór] i izotopami z szeregu torowego oraz z szeregu uranowo-aktynowego.
EN
Data on natural radionuclides: potassium [formula], lead [formula], bismuth [formula], actinium [formula] and thallium [formula] in soils of northeastern Poland in aspect of soil properties were presented and discussed. The content of natural radionuclides in studied soils was variable and depended on physical and chemical properties of soils. Some correlation between the [formula] concentration and the other natural radionuclides concentration have been found.
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