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Natural radionuclides in rocks and their association with the mineralogy of rocks in Dakshina Kannada region of southern India

Lokesh Narsha, Vinutha Pudiyaneravana Ramanand, Malleshi Kavasara, Narayana Yerol

Acta Geophysica

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2022

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Vol. 70, no 5

2149--2160

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.

2

Preliminary characterization of the radioactivity in sediments taken from Jamske Pleso lake (Slovakia)

Szaciłowski Grzegorz, Szarłowicz Katarzyna, Kubica Barbara

Ecological Chemistry and Engineering. A

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2018

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Vol. 25, nr 2

215--222

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.

3

Natural Radioactivity at the Sin Quyen Iron-Oxide- Copper-Gold Deposit in North Vietnam

Nguyen D. C., Khanh P. L., Jodłowski P., Pieczonka J., Piestrzyński A., Van H. D., Nowak J.

Acta Geophysica

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2016

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Vol. 64, no. 6

2305--2321

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.

4

Kolekcjonowanie minerałów zawierających naturalne radionuklidy w świetle polskiego prawa

Dziubiak T.

Postępy Techniki Jądrowej

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2012

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z. 4

33--35

5

Transport naturalnych nuklidów promieniotwórczych w ekosystemie gleba - szata roślinna.

Niesiobędzka K.

Chemia i Inżynieria Ekologiczna

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1999

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Vol. 6, nr 1

77-87

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.