Analysis of Potassium-40 (40K) in Soil Samples from Dhahran City, Saudi Arabia, Using Gamma Spectrometer

2020 ◽  
Vol 46 (1) ◽  
pp. 731-735
Author(s):  
Nidal Dwaikat
2005 ◽  
Vol 48 (spe2) ◽  
pp. 221-228 ◽  
Author(s):  
José Araújo dos Santos Júnior ◽  
Jorge João Ricardo Ferreira Cardoso ◽  
Cleomacio Miguel da Silva ◽  
Suêldo Vita Silveira ◽  
Romilton dos Santos Amaral

Potassium-40 was determined in soil in an area with 40,000 m² situated in the western State of Pernambuco, Brazil. For radiometric measurements, the gamma spectrometry method with a high purity germanium (HPGe) detector was used. Sampling of 78 soil samples has been performed at intervals of 25 m. The specific activities of 40K were calculated based on the photopeak of 1.46 MeV. Values from 541 to 3,572 Bq kg-1 were obtained (mean of 1,827 Bq kg-1). These values allowed the determination of the elemental concentrations as well as the absorbed dose rates in air, 1 m above the ground. The values varied from 1.7 to 11.5% (mean of 6%) and from 23.4 to 154.3 nGy h-1 (mean of 79 nGy h-1), respectively.


2021 ◽  
Vol 11 (6) ◽  
pp. 20-29
Author(s):  
Fetoon M ◽  
helaiwi Alk ◽  
Ismet Ara ◽  
Nadine Moubayed

Streptomyces are the most popular among the Actinomycetes groups and found in soils worldwide. They form an important part of the soil ecology within the Actinomycetales order. Streptomyces are diverse as secondary antibiotic metabolites such as Novobiocin, Amphotericin, Vancomycin, Neomycin, Gentamicin, Chloramphenicol, Tetracycline, Erythromycin and Nystatin. Thus, the current study was aimed to isolate, identify and assess the active antibiotic metabolites produced by different actinomyces sp. found in Saudi Arabian soils. Six samples were collected from desert soils of the Al Thumamah area and analyzed using GS-MS. Scanning Electron Microscopy was used to identify the bacterial strains along with their antibiotic metabolites effectiveness of secondary metabolites (antibiotics) against different Gram-positive (Bacillus subtilis, Staphylococcus aureus), negative pathogens (Pseudomonas aeruginosa, Escherichia coli, Salmonella suis, and Shigella sonnei) as well as the fungal strain Candida albicans was investigated. Thirty active bacterial (F1-30) strains were isolated from the soil samples and the strains F3, F7, F22, F30 have white, gray, pink, yellow and red colours respectively. Only ten strains (F13, F14, F15, F16, FI7, F18, F19, F20, F21, and F22) were found to have antimicrobial activity against at least one pathogen. The optimum growth environment was pH 4-10, temperature (300C), and NaCl (7% w/v) concentration. According to our findings, the extreme desert environment of Al Thumamah from Saudi Arabia is rich in its actinobacterial population with diverse colouring groups and various physiological and biochemical properties. This shows it’s capability of generating secondary metabolite elements that could inhibit pathogenic microorganisms.


2021 ◽  
Author(s):  
Lubna A. Alasadi ◽  
Ali Abid Abojassim

Abstract The aim from this work is to detect and draw the natural radioactivity of (uranium-238, thorium-232 and potassium-40) levels in soil samples that taken from Kufa districts, Najaf governorate, Iraq. The detection system used in study is NaI (Tl) with "3x3" dimension, while maps were drawn by geographic information system (GIS). Some radiological parameters were calculated depending on measuring of specific activity for 238U, 232Th, and 40K. The results of the average value with standard error in all samples of the present study for 238U, 232Th, 40K, and 235U were 6.2±0.74, 6.41±0.82, 278.10±19.43, and 0.28±0.03 Bq/kg, respectively. The specific activity of Uranium-238, Thourium-232, poasium-40 and Uranium-235 found in all soil samples were within the safety limit reported by UNSCEAR, except three samples have poasium-40 higher than safety limit. Also, the results of radiological parameters were all found to be below OECD, UNSCEAR safety limit. Generally, the average of specific activity in soil collected arranged of potassium-40 > thorium-232 > uranium-238. Mapping GIS for natural radioactivity and some radiological parameters were successfully draw for the study area. Finally, natural radioactivity and radiological parameters for soil samples at Kufa districts were safety.


2019 ◽  
Vol 188 (3) ◽  
pp. 299-310 ◽  
Author(s):  
Y Y Ebaid

Abstract The enhancing effect due to long-time irrigation with radium-containing groundwater on soil was investigated in this work. Samples from the Al-Qassim and Hail areas in Saudi Arabia were studied for their 226Ra and 228Ra inventories. Groundwater and soil samples were collected from 32 farms where agricultural activities are intensively irrigated with radium-containing groundwater. A noticeably good correlation was observed between radium isotopes inventories in the groundwater used for irrigation with those in the associated soils. It was concluded that there are enhanced levels of radium isotopes in the soils due to the existence of radium isotopes in irrigated groundwater. The additional annual effective dose values ranged between 0.00 and 0.412 with an average of 0.09 mSv y−1.


2021 ◽  
Vol 14 (2) ◽  
pp. 66-71
Author(s):  
S. V. Muminov ◽  
B. B. Barotov ◽  
U. M. Mirsaidov ◽  
S. R. Murodov ◽  
J. A. Salomov ◽  
...  

The content of cesium-137 in the soil cover of the central and southern parts of Tajikistan was studied. The study area of the regions of the republic is about 45,000 km2. 92 soil samples from the Central and Southern parts of the republic were collected from cultivated and uncultivated fields to a depth of 25 cm from the ground surface. Each sample at the sampling point was cleared of stones, roots and other inclusions. The sample was dried to an air-dry state, crushed and sieved through a sieve with a hole diameter of 2 mm. When measuring the samples, we used a standard 1 L Marinelli beaker. Measurements of the specific activity of cesium-137 in soil samples were carried out on a gamma spectrometer based on highly pure germanium. The maximum content of cesium-137 was observed in soil sample No. 1 of the Kamarob area of the Rasht district, which specific activity in the sample is 148 Bq / kg. The minimum specific activity of cesium-137 is observed in soil samples from the Tajikabad district. The dependence of the concentration of cesium-137 on the topography in the region under study has been established. In some of the investigated samples, the cesium-137 isotope was not detected (sample no. 2 from the Ayvaj area of the Shahritus district and sample no. 4 from the Farkhor district). The dynamics of the distribution of cesium-137 on the soils of uncultivated fields and soils of cultivated fields of the Khatlon region of Tajikistan has been studied. It was found that the content of the isotope of cesium-137 in the treated fields differs from the untreated ones. It has been determined that in the soils of cultivated lands, the content of cesium-137 is concentrated at a depth of 20-25 cm. At the foot of the mountains and clay soils, a relatively high content of the isotope of cesium-137 is observed in comparison with plains and sandy soils.


2019 ◽  
Vol 2 (4) ◽  
pp. 119-125
Author(s):  
Sonexay Xayheungsy ◽  
Khiem Hong Le

Results of the first investigation of the activity concentration of the surface soil samples collected at various locations of Thoulakhom district of Vientiane province of Laos People's Democratic Republic (PDR) are presented in this work. The activity concentration of the natural radionuclides 226Ra, 232Th and 40K in the soil samples were determined by gamma spectrometer using a highenergy resolution semiconductor detector HPGe. The activity concentrations of the natural radionuclides were in the range from 11.28 to 31.46 with the mean of 21.76 Bq.kg-1 for 226Ra, from 7.13 to 44.47 with the mean of 21.85 Bq.kg-1 for 232Th and from 8.96 to 581.52 with the mean of 112.89 Bq.kg-1 for 40K. These mean values of the activity concentration were lower than the average worldwide ones, which were 33, 45 and 420 Bq.kg-1 for 226Ra, 232Th, and 40K, respectively. The results indicate dthat the radiation hazard from natural 226Ra, 232Th, and 40K radionuclides in all investigated soil samples taken from area under investigation in this work was not significant.


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