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A geochemical study of rare earth elements (REEs), uranium (U), thorium (Th) and major elements was conducted in mylonitic rocks found in north Abu Rusheid, south eastern desert, Egypt, a well-known uranium ore deposit area. The concentrations of REEs, U, and Th were measured using inductively coupled plasma mass spectrometry. ∑REEs varied from 38 to 183 µg/g with a mean value of 90 µg/g. U and Th concentrations varied from 67 to 171 and 98 to 454 µg/g, respectively. The mean value of the U/Th ratio was higher than the upper continental crust value and the mylonitic rocks were concluded to have high U content. [ABSTRACT FROM AUTHOR]

Absorbed dose rate in air for the Tehri Garhwal region of Uttarakhand state, India was measured using a vehicle-mounted NaI(Tl) scintillation spectrometer. The average values of absorbed dose rate in air for Jakhana and New Tehri areas in this region were 150 nGy h−1 and 88 nGy h−1, respectively, and the respective estimated average external effective doses for the areas were 1.06 mSv y−1 and 0.62 mSv y−1. Higher dose rates observed in the Jakhana area were possibly related to uraninite and sericite which were formed as a result of hydrothermal alteration and found in the area. [ABSTRACT FROM AUTHOR]

Distributions of 226Ra, 232Th and 40K were studied in the coastal region of Kanyakumari district, a high background natural radiation area (HBNRA). The absorbed gamma dose rate ranged from 107 ± 11 to 41,126 ± 187 nGy/h. The radiation hazard parameters were found to be much higher than the UNSCEAR world average values. 232Th/226Ra activity ratios ranged from 3 to 45, which indicates the collected sand samples may be rich in Th bearing monazite minerals that are mainly responsible for the enhanced radiation level in the Kanyakumari HBNRA. [ABSTRACT FROM AUTHOR]

The activity concentrations of 226Ra, 232Th and 40K were determined in 43 soil samples collected from 0 to 10 cm and 10 to 50 cm depths of Niška Banja region, Serbia, using a low background gamma spectroscopy with 3″ × 3″ NaI(Tl) scintillation detector. The mean absorbed dose rate of 0–10 cm and 10–50 cm depth soil were 66.1 and 60.4 nGy/h, respectively which was close to UNSCEAR worldwide value. The radium equivalent and annual effective dose effect were lower than the permissible level. Therefore, there is no significant radiological risk from the soil to residents living in this region. [ABSTRACT FROM AUTHOR]

In this paper, DGA-normal resin has been used for the chemical separation of Sr and Y from Cs as well as other elements in standard solutions. The decontamination factor of Cs was tested in different acidic media. It was found that 8 M HNO3 was the most effective rinsing solution with a Cs decontamination factor exceeding 400,000. Application of the DGA-normal resin allows the separation of Y and Sr from other interfering beta emitter isotopes. This resin is suitable for 90Sr and 90Y separation in contaminated Fukushima soil samples giving the prospect of 90Sr measurement in a direct (90Sr) and indirect way (90Y). [ABSTRACT FROM AUTHOR]

Absorbed dose rates in air for 20 residential areas in Odisha were measured using a vehicle-mounted NaI(Tl) scintillation spectrometer. The average values and standard deviations of absorbed dose rate in air for seaside and inland areas were 230 ± 116 nGy h−1 and 123 ± 18 nGy h−1, respectively. The annual external effective dose ranged from 0.43 to 4.59 mSv y−1 with the average value of 1.29 mSv y−1; this indicated there were wide deviations. Analysis of measured data showed that 232Th and 238U were concentrated in the seaside area. [ABSTRACT FROM AUTHOR]

The stable 90Zr isotope causes isobaric interferences with 90Sr determination during inorganic mass spectrometry applications. To avoid interference of 90Zr, chemical separation of Zr from Sr is carried out using extraction chromatography resins. In this study, Zr decontamination factors were determined with Eichrom DGA and Sr resins. The Zr decontamination factor of Sr resin (~ 104) was one magnitude higher than DGA's (~ 103). The recovery of Sr was around 90% in both resins. In a combination of two separation steps either using DGA-Sr resin or Sr-Sr resin, a Zr decontamination level of 107-108 could be achieved. [ABSTRACT FROM AUTHOR]

The presence of anomalous terrestrial radioisotopes must be suspected in black shale-hosted manganese ore deposits, based on high organic matter content, which is useful tool in genetic, among them paleoenvironmental investigations. Our work aims at the characterization of the paleoredox conditions of the Úrkút Manganese Formation based on comparison of terrestrial radioisotopes and selected element ratios. Paleoredox indicators were estimated on U/Th, δU, Ni/Co, V/Cr, V/(V + Ni) and Ce*. The results of paleoredox indicator element ratios show, that these methods must be used with caution (microbial selective element enrichments, mobilizations), and the complex interpretation using mineralogy and microtexture can be recommended. [ABSTRACT FROM AUTHOR]

A pilot study to measure ambient gamma dose rate and radon and thoron progeny concentrations was made for eight dwellings selected in Yangjiang, China. Indoor and outdoor ambient gamma dose rates were 110-370 and 100-220 nGy h, respectively. Doses received from indoor terrestrial radiation were estimated to be 0.6-1.8 mSv year. Radon, thoron and thoron progeny concentrations were 19-98, 18-1120 and 0.4-10.3 Bq m, respectively. This pilot study showed that the position of passive-type monitors to be placed and the deployment period should be carefully determined for estimating reliable annual average concentrations. [ABSTRACT FROM AUTHOR]

Natural radioactivity in surface soil samples collected at potential sites from southern part of Thailand to set up nuclear power plants has been investigated. U and Th were determined by inductively coupled plasma mass spectrometry whereas gamma-ray spectroscopy was used for K determination. The activity concentrations for U, Th and K varied in range from 4 to 122, 6 to 170 and 5 to 1,422 Bq kg, respectively. The large variation of radionuclide concentrations showed heterogeneous distribution that could be attributed to geological origin. The radiation hazard parameters were estimated from activity concentration of U, Th and K in accordance with the UNSCEAR 2000. Data obtained indicated that soils in the study areas did not pose any significant radiological health hazard to the local population. [ABSTRACT FROM AUTHOR]