scholarly journals Influence of background characteristics on the optimal sample filling height in gamma-ray spectrometry

2020 ◽  
Vol 326 (1) ◽  
pp. 343-347
Author(s):  
H. Ramebäck ◽  
T. Vidmar
Keyword(s):  
Water Sample ◽  
Gamma Ray ◽  
Natural Radionuclides ◽  
Gamma Ray Spectrometry ◽  
Background Characteristics ◽  
Sample Container ◽  
Filling Height ◽  
Naturally Occurring Radionuclides ◽  
Energy Gamma ◽  
Zircon Sand

Abstract The minimum detectable activity (MDA) for gamma spectrometric measurements was studied as a function of filling height for two detectors having different background characteristics and for two sample matrices: a water sample with a low content of natural radionuclides, and zircon sand, with high activities of uranium and thorium. The zircon sand is also a material in which the self-attenuation of low-energy gamma photons will be high. The results show that for the water sample it is always favourable to completely fill the sample container. However, due to the inherent content of naturally occurring radionuclides in the zircon sand the MDA may not necessarily improve with the filling height, since an increased amount of sample will increase the background in the spectrum as well.

scholarly journals VZTAH MEZI PŘIROZENOU RADIOAKTIVITOU HORNIN A PŮD NA NICH VYTVOŘENÝCH – ZÁKLADNÍ PROBLÉM INTERPRETACE DAT ZÍSKANÝCH LETECKOU A TERÉNNÍ GAMASPEKTROMETRIÍ

2016 ◽  
Vol 22 (1-2) ◽  
Author(s):  
Jiří Zimák
Keyword(s):  
Natural Radioactivity ◽  
Gamma Ray ◽  
Natural Radionuclides ◽  
Size Fraction ◽  
Mineralogical Composition ◽  
Gamma Ray Spectrometry ◽  
Spectrometric Analysis ◽  
Radiation Dose Rate ◽  
Parent Rocks ◽  
Mass Activity

The objective of this study was to assess the amount of natural radionuclides in fresh parent rocks and their effect on natural radioactivity of soils developed from them. Forty-five fresh rocks consisting mainly of granitoids, syenitoids, acid to basic metavolcanites, mica schists, gneisses, quartzites, serpentinites, sandstones, graywackes, and limestones and their corresponding overlying soils were sampled for laboratory gamma-ray spectrometric analysis. Contents of potassium, uranium and thorium were converted to mass activity of 226Ra equivalent (am) and terrestrial gamma radiation dose rate (D). Data are tabled and discussed. The highest am values occured in syenitoids (386–441 Bq·kg-1) followed by granitoids, mica schists, greywackes and gneisses, whereas the lowest am values were found in quartzose sandstones (15–36 Bq·kg-1) followed by limestones (less than 15 Bq·kg-1) and serpentinites (less than 6 Bq·kg-1). The natural radioactivity of soils is usually slightly lower than that of parent rocks due to the lower content of potassium, uranium and thorium in soils. This is typical for granitoids, syenitoids and rocks of similar mineralogical composition. In soils developed on granitoids and syenitoids were found increased concentrations of all three elements in the grain size fraction below 0.063 mm. Soils developed on rocks with low natural radioactivity (such as limestones and serpentinites) tend to have significantly higher natural radioactivity than their parent rocks. This may complicate the interpretation of data obtained by airborne gamma-ray spectrometry.

scholarly journals Inter-comparison exercise utilizing x- and γ-ray spectrometry

2020 ◽  
Vol 27 ◽  
pp. 121
Author(s):  
Filothei K. Pappa ◽  
Christos Tsabaris ◽  
Dionisis Patiris ◽  
Georgios Eleftheriou ◽  
Effrossini G. Androulakaki ◽  
...  
Keyword(s):  
Gamma Ray ◽  
Natural Radionuclides ◽  
Atomic Spectrometry ◽  
Gamma Ray Spectrometry ◽  
Metal Concentrations ◽  
Activity Concentrations ◽  
Great Divergence ◽  
Set Up ◽  
Comparison Exercise ◽  
Good Agreement

Radionuclides are characterized by their nuclear and chemical behavior. Additionally, the geochemical characteristics of radionuclides result in their accumulation in the sediments via sorption processes. In this work the radionuclide activity concentrations obtained by gamma-ray spectrometry (HPGe detector) were converted to metal concentrations as described in [1]. The results were compared with the measured metal concentrations obtained by atomic spectrometry (X-ray fluorescence system-XRF). The samples originate from the coastal environment of two Greek areas, characterized by elevated values of natural radionuclides (e.g. 226Ra) and metals. The preliminary study revealed a good agreement among the concentrations of potassium calculated via activity concentrations of 40K and those of XRF measurement, while a great divergence was observed for the thorium case. These differences can be attributed to the low statistics, as well as to the calibration set-up of Th XRF measurement.

ESTIMATION OF RADIOLOGICAL HAZARDS DUE TO NATURAL RADIONUCLIDES FROM THE ROSTERMAN GOLD MINE TAILINGS, LURAMBI, KAKAMEGA, KENYA

2020 ◽  
Vol 190 (3) ◽  
pp. 324-330
Author(s):  
C K Wanyama ◽  
F W Masinde ◽  
J W Makokha ◽  
S M Matsitsi
Keyword(s):  
Gamma Ray ◽  
Natural Radionuclides ◽  
Absorbed Dose ◽  
Spectrometric Analysis ◽  
Gold Mine ◽  
Absorbed Dose Rate ◽  
Radiological Hazards ◽  
Naturally Occurring Radionuclides ◽  
Gold Mine Tailings ◽  
Radiological Health

Abstract Radiological hazards associated with naturally occurring radionuclides in materials from Rosterman gold mine were assessed by analysis of 30 samples. The gamma-ray spectrometric analysis of tailing samples reported an average activity concentration of 263 ± 13, 123 ± 6 and 84 ± 4 Bq kg−1 for 40K, 232Th and 226Ra, respectively. The average absorbed dose rate was 124 ± 6 nGy h−1, while the annual effective dose of 0.4 ± 0.02 mSv y−1 for indoor and 0.3 ± 0.01 mSv y−1 for outdoor were reported. The mean and range of radiological parameters (external and radium equivalent) calculated from the tailing samples were within the permissible limits and hence mining of gold at Rosterman has no significant radiological health implication on the miners and the surrounding population.

scholarly journals Natural Radioactivity, Radiological Hazard and Petrographical Studies on Aswan Granites Used as Building Materials in Egypt

2021 ◽  
Vol 11 (14) ◽  
pp. 6471
Author(s):  
Nasser M. Moghazy ◽  
Amira M. El-Tohamy ◽  
Mona M. Fawzy ◽  
Hamdy A. Awad ◽  
Hesham M. H. Zakaly ◽  
...  
Keyword(s):  
Natural Radioactivity ◽  
Building Materials ◽  
Gamma Ray ◽  
Natural Radionuclides ◽  
Polarized Light ◽  
Environmental Parameters ◽  
Mineralogical Composition ◽  
Eastern Desert ◽  
Granitic Rocks ◽  
Gamma Ray Spectrometry

The present study was carried out on commercial types of Aswan granite used as building and decorative materials. Nearly 29 granitic rocks samples from 11 classes (black Aswan, red Aswan, dark Rosa, light Rosa, yellow Verdi, grey Shirka, Gandolla, Forsan, red Nefertiti, Royal, and white Halayeb) were collected from three stations near Aswan city for petrographical description and assessment of natural radioactivity. The petrographical study of granites was conducted by polarized-light microscope in order to determine their mineralogical composition and investigate their texture; the activity of the natural radionuclides 238U, Ra226, 232Th, and 40K was measured by gamma-ray spectrometry with a NaI(Tl) detector. The average values of the activities, 52.2 Bq kg−1, 57.8 Bq kg−1, 31.2 Bq kg−1, and 1055.7 Bq kg−1 of U-238, Th-232, Ra-226, and K-40, respectively, were higher than that the world average values of 35 Bq kg−1, 30 Bq kg−1 and 400 Bq kg−1 for 226Ra, 232Th, and 40K, respectively, according to the recommended levels from UNSCEAR reports. The minimum and maximum values obtained were compared with the value ranges from other locations in the Eastern Desert, highlighting the fact that that the maximum values obtained in this work are higher than those in other areas. According to the radiological hazards indices results, most samples lie in the permissible level ranges, suggesting their favorability for use as building materials. In contrast to that, some samples have some environmental parameters higher than the international levels, indicating their unsuitability as building materials.

Transfer of natural radionuclides from soil to plants in Savar Dhaka

2017 ◽  
Vol 7 ◽  
Author(s):  
M. Haque ◽  
J. Ferdous
Keyword(s):  
Soil Properties ◽  
Nuclear Reactor ◽  
Gamma Ray ◽  
Natural Radionuclides ◽  
Gamma Ray Spectrometry ◽  
Free Access ◽  
Transfer Factors ◽  
The Public ◽  
Activity Concentrations ◽  
Plant Transfer

The radioactivity of environmental samples from nuclear reactor sites must be analyzed before the public is given free access to the plants grown in these soils. Plant and corresponding soil samples were collected from a sample site around the Savar research reactor near Dhaka (Bangladesh) and the activity concentrations of natural radionuclides <sup>226</sup>Ra (<sup>238</sup>U-chain), <sup>228</sup>Ra (<sup>232</sup>Th-chain) and non-chained <sup>40</sup>K were measured using gamma ray spectrometry. Soils of Savar contained more radioactive <sup>40</sup>K than <sup>226</sup>Ra and <sup>228</sup>Ra. The influence of certain soil properties on the activity concentrations and transfer factors (TF) of natural radionuclides were investigated by correlating the observed data with those of soil properties. The activity concentrations of <sup>40</sup>K were much higher than those of <sup>226</sup>Ra and <sup>228</sup>Ra in plants due to higher uptake from soils. The transfer factors for <sup>226</sup>Ra, <sup>228</sup>Ra and <sup>40</sup>K were found to range from 0.04 to 0.10, 0.12 to 0.32, and 0.24 to 0.72, respectively. The soil to plant transfer factors for <sup>40</sup>K was found to be much higher in plants, which might be due to this element being vital in plants. This study showed that activity concentrations of these radionuclides in plants and their plant transfer factors seem to depend on the activity concentrations of the same radionuclides in soil.</p><p><strong> </strong>

NATURAL RADIONUCLIDES IN AGRICULTURAL PLANTS FROM NORTHERN THAILAND

2019 ◽  
Vol 184 (3-4) ◽  
pp. 397-399
Author(s):  
R Kritsananuwat ◽  
C Kranrod ◽  
S Chanyotha ◽  
T Ploykrathok ◽  
P Sriploy
Keyword(s):  
Gamma Ray ◽  
Natural Radionuclides ◽  
Northern Region ◽  
Soil Samples ◽  
Gamma Ray Spectrometry ◽  
Northern Thailand ◽  
Activity Concentrations ◽  
Plant Samples ◽  
Spectrometry Technique ◽  
Agricultural Plants

Abstract Thailand is predominantly an agricultural country. The Northern Region occupies the second largest cultivated land area in the country. To establish baseline data for future environmental monitoring, seventy-nine plant samples including vegetables, fruits and tobaccos and their relevant soils were collected from the major plantation zones of Northern Thailand. Activity concentrations of natural radionuclides in the samples were determined using gamma-ray spectrometry technique. The median activity concentrations of 226Ra and 228Ra in the soil samples were higher than worldwide value, while as those of 40K were comparable with worldwide value. There was a large variation and non-uniform distribution in the soil samples. The activity concentrations of 226Ra, 228Ra and 40K in the plant samples varied widely within plants and between species and were very low compared to their relevant soils. A decreasing trend of their activity concentration has been observed in the order leaf > stem > rhizome/root (as found in galangal); and leaf > stalk/stem (as found in lemongrass).

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