Presence Of 40K Research Articles

The occurrence of 40K and 137Cs radioactivity in mosses during 2015-2019 in the Djerdap National Park (E. Serbia).

The radiation status of the national park (NP) Djerdap (Eastern Serbia) is characterized using bioindicators (mosses). Mosses (16 species, 156 samples) were collected randomly within the area of NP Djerdap during the month of June, periodically from 2015 to 2019. Samples were collected in the regions of Dobra, Donji Milanovac, and Tekija. Within the mosses, the presence of 40K and 137Cs is regarded as a good indicator of radionuclides present in the environment due to their easy interchangeability with 39K highly present in living moss organisms. The activity concentrations of gamma ray-emmiting radionuclides in samples were determined using high-resolution gamma ray spectrometry, an HPGe-ORTEC/Ametek detector. The determining activity concentrations of 40K and 137Cs in collected samples were as follows: for 40K from 31.4 to 721Bqkg-1and for 137Cs varied from 2.6 to 908Bqkg-1. The average activity concentrations of 40K and 137Cs (Bq kg-1) in mosses in the period 2015-2019 were the lowest in moss samples collected in the Dobra region, and the highest in the area of Donji Milanovac. The most prevalent collected moss species within the Djerdap National Park was Hypnum cupressiforme. The determined activity concentrations in H. cupressiforme of 137Cs for the whole region of NP Djerdap for all 5years was 78.1 ± 70.3Bqkg-1 and of 40K was 181 ± 86.1Bqkg-1.

Ingestion Dose and Elemental Composition in Coffee by X-Ray Fluorescence and Gamma-Ray Spectrometry

The study proposed in this paper aims to analyze macro and micronutrients in coffee powder samples from Brazil, Venezuela and Colombia, in two different stages of coffee preparation: before and after coffee filtering. In the analyzed samples, presence of K, Rb, Ca, Cl, S, Sr and Fe elements in coffee powder and coffee grounds using Energy Dispersive X-ray fluorescence (ED-XRF) was quantified. The presence of 40K and the radionuclides from the uranium and thorium series decays were verified using gamma-ray spectrometry analyses. With the results obtained using these two techniques, it was possible to estimate the ingestion index for natural radioisotopes. The results show that the annual dose due to coffee ingestion reaches 1.96(4) mSv, depending on the origin of the coffee and considering the annual coffee consumption in Brazil. Elemental Composition analysis of coffee grounds indicates that it can be reused as a product with a high concentration of nutrients.

Optimization of data acquisition parameters for single gamma line sensing: KSr2I5:Eu2+ and NaI(Tl) compared

Abstract KSr2I5:Eu 2 + scintillators exhibit better than 3% energy resolution at 662 keV and may be significantly less expensive to produce than other, similar energy resolution scintillators. However, KSr2I5:Eu 2 + exhibits a 6.5 Bq/cm3 intrinsic background from the presence of 40K. This background is not only the well-known 1.46 MeV gamma, but also the 1.31 MeV end point of the beta spectrum. This paper computationally evaluates the optimum data acquisition parameters of KSr2I5:Eu 2 + and compares them to NaI(Tl) for the detection of single line gamma sources between 0.01–2.2 MeV with incident source strengths between 5 s−1 and 100 s−1 striking the detector. We found a strong dependence of the time-to-detection on the data acquisition parameters, where the time-to-detection of KSr2I5:Eu 2 + was 1–3 times larger than NaI(Tl) across the parameter space. The largest discrepancy observed was between 0.6 MeV and 1.2 MeV, where the intrinsic 1.31 MeV beta dominates the background.

A comparison approach to explain risks related to x-ray imaging for scoliosis

source is 222Rn, which on average accounts for 1.2 mSv / y (range 0.2 +/-10 mSv / y). Cosmic rays (0.4 mSv / y, range 0.3 +/-1.0) and terrestrial gamma rays from other radionuclides (0.8 mSv / y, range 0.3 +/- 1.4) are additional sources of natural radiation. Moreover, flying from Europe to North America accounts for 0.03-0.05 mSv, and because of the unavoidable presence of 40K, consuming 1,000 bananas, or carrots, accounts for approx. 0.1 mSv. Overall, 65% of the world population is expected to be exposed to an annual E between 1 and 3 mSv (average 2.4 mSv) [1]. Conclusions Data coming from literature show how, on average, the effective annual dose coming from natural sources greatly exceeds the effective dose due to x-ray imaging for scoliosis. This information can play a key role in the relationship between physicians and patients.

Radioactive survey of coastal water and sediments across Alexandria and Rashid coasts

Alexandria and Rashid being part of the Mediterranean Sea basin cities are concerned with the protection of the marine environment of their territorial waters and coasts. One of the major sources of pollution in the surface water and sediments is the radionuclides.The present study is devoted to reliable detection, identification and classification of the radionuclides using the gamma ray spectrometer to measure the density of the radionuclides (i.e. 238U, 232Th, 40K) along the Alexandria and Rashid beaches and try to know the sources of these radionuclides.Surface sediments and sea water samples were collected from Alexandria and Rashid coastal beaches. The results demonstrate that the main source of radiation along the Alexandria and Rashid beaches is the black sands, which is rich in radio-nuclides, supplied by the River Nile during the flooding period in the last 5000years through the Rashid branch of the Nile. These black sands accumulate mostly on the Rashid beach. The sea waves carry part of these black sands to Alexandria beaches westward.The distribution of 40K along the Alexandria coast revealed that, the western area of Al-Max coast was poor in 40K. On the other hand, the eastern area of Alexandria was rich in 40K, there was a wide relationship between the presence of 40K in sediments and the biological density of fauna and flora in the coast. The behavior of 40K in sediments along the Alexandria coast has been detected as non-uniform correlations between the data at different stations reveal significant differences between their radiometric properties. The lower 40K values for seawater have been detected at stations receiving low saline water discharged from inland sources. The salinity affects the behavior of 40K in surface seawater. This was due to the solubility of 40K in seawater.The measured values for 238U and 232Th for seawater are very low.The continuous monitoring of the radio-nuclides is recommended to assure good environment of these beaches because they are bathing beaches of Alexandria, and an important resource as summer resort.

Assessment of radioactivity level in bore hole-soil in Nigeria

Radioactivity level in six soil samples from different boreholes in Zaria, Nigeria was assessed. The presence of 40K, 226Ra and 232Th were analyzed using γ -ray spectrometry with sodium iodide thallium, {NaI(Tl)} detector. Mean specific activity of 1020.4 ± 12.4, 123.1 ± 2.3 and 25.7 ± 2.0Bq/kg for 40K, 226Ra and 232Th, respectively were obtained. The radioactivity level for each location was calculated to ascertain the risk involved in using these boreholes. This radiation index revealed that all the locations are safe except two locations having radioactivity level of approximately 1.02 and 1.30 Bqkg-1,respectively, which are well above the world quoted value of unity. This shows that the concentration levels for these two areas are high and it is therefore recommended that none of these boreholes’ water be consumed in order to avoid unnecessary exposure and absorption of dosage of radiation that will be threatening to life. Key words: Radioactivity level, borehole-soil, γ-ray.

Gamma Emitters on Micro-Becquerel Activity Level in Air at Kraków (Poland)

The Petryanov air filters combined into half-year sets were analyzed for the presence of 40K, 137Cs and 22Na by means of low-background gamma rays spectrometry. Each sample contains aerosols from more than 1 Mm3 of air. Samples were collected in ground level air at Krakow (Southern Poland) from 1996 to 2002. Activity concentrations of 40K are almost constant with the mean of 14.7± 4.5 μ Bq m−3. Activity concentrations of 137Cs, which are on the level of single μ Bq m− 3 show exponential decrease with effective half-life time of 7.07± 0.77 years. The cosmogenic 22Na shows a strong seasonal variation with significant different mean values activity concentration between 0.333± 0.095 μ Bq m−3 and 0.137± 0.045 μ Bq m−3, for summer and winter, respectively. Moreover, the activity ratio for two cosmogenic radionuclides: 22Na and measured previously 7Be show also changes with statistically significant seasonal differences. The lower values were found during winters. The mechanisms which might govern this ratio are discussed. The conclusion is that transport of 22Na during summer seems to be so much effective, that results in kind of relative depletion of stratosphere of this nuclide.