scholarly journals Surface Contamination and Dose Rate Verification of Fertilizers common in Iraqi Plantations using RadEye B20 Detector

2020 ◽  
Vol 33 (4) ◽  
pp. 42
Author(s):  
Yassir A. Baqir ◽  
Nada Farhan Kadhim

Twenty three samples of granular chemical fertilizers and organic fertilizers commonly utilized in Iraqi ranches were collected. The samples were prepaid and stored in a Marinelli beaker to measure; dose rate, general count rate and surface contamination of the samples using the RadEye B20 detector, firstly with shield, secondly without the shield to estimate the effect of shielding on the measurements. The results showed that using shield made a significant decrease in the radiation measurements reached about 25%. However the mean value of surface contamination, dose rate and general count rate with shield were 0.54Bq/cm2, 0.65µsv/h, and 0.28Cps respectively, and without shield being 0.34Bq/cm2, 1.33µsv/h, and 1.52Cps respectively.

2014 ◽  
Vol 7 (1) ◽  
pp. 5-11 ◽  
Author(s):  
Rabindra N. Padhy ◽  
Nabakishore Nayak ◽  
Shakti Rath

Abstract Effects of chemical fertilizers (urea, super phosphate and potash) on toxicities of two carbamate insecticides, carbaryl and carbofuran, individually to the N2-fixing cyanobacterium, Cylindrospermum sp. were studied in vitro at partially lethal levels (below highest permissive concentrations) of each insecticide. The average number of vegetative cells between two polar heterocysts was 16.3 in control cultures, while the mean value of filament length increased in the presence of chemical fertilizers, individually. Urea at the 10 ppm level was growth stimulatory and at the 50 ppm level it was growth inhibitory in control cultures, while at 100 ppm it was antagonistic, i.e. toxicity-enhancing along with carbaryl, individually to the cyanobacterium, antagonism was recorded. Urea at 50 ppm had toxicity reducing effect with carbaryl or carbofuran. At 100 and 250 ppm carbofuran levels, 50 ppm urea only had a progressive growth enhancing effect, which was marked well at 250 ppm carbofuran level, a situation of synergism. Super phosphate at the 10 ppm level only was growth promoting in control cultures, but it was antagonistic at its higher levels (50 and 100 ppm) along with both insecticides, individually. Potash (100, 200, 300 and 400 ppm) reduced toxicity due to carbaryl 20 and carbofuran 250 ppm levels, but potash was antagonistic at the other insecticide levels. The data clearly showed that the chemical fertilizers used were antagonistic with both the insecticides during toxicity to Cylindrospermum sp.


2020 ◽  
Vol 35 (2) ◽  
pp. 154-164
Author(s):  
Sreten Ilic ◽  
Tatjana Golubovic ◽  
Natasa Pajic ◽  
Mirjana Djurasevic ◽  
Aleksandar Kandic

This paper presents the results of analyses of radionuclide content in the samples of the surrounding soil and clayey material of ?Zbegovi? open-pit mine in Donje Crniljevo, Serbia. Samples from 78 sites were collected and prepared. The activity concentrations were determined for radionuclides: 238U, 232Th, 40K, 226Ra, and 137Cs. The mean values obtained are as follows: 23 Bqkg?1, 89 Bqkg?1, 372 Bqkg?1, 56 Bqkg?1, and 11 Bqkg?1, respectively. Concentrations of 238U, 40K, and 226Ra in the studied area do not deviate from the values obtained for the soil in Serbia. The concentration of 232Th in the studied area is slightly higher relative to average values for soil, and slightly lower compared to similar deposits of clayey material in the world. Measurements performed showed that the open-pit mine of clayey material is completely uncontaminated surface as far as 137Cs is concerned, while there are sites where measured 137Cs concentrations are significantly higher, which is due to topographic differences and inhomogeneous surface contamination of land after the Chernobyl accident. To assess the radiological risks in the observed area, the following indices were determined: absorbed dose rate, annual outdoor effective dose, absorbed dose for biota, excess lifetime cancer risk outdoors as well as external radiation hazard index. The mean value of the estimated absorbed dose rate in the given area amounts to 80.1 nGyh?1, and the annual outdoor effective dose ranges from 46.9 to 134 Sv. Absorbed dose rate for biota in the studied area is 1.31 10?4 Gyd?1. The mean excess lifetime cancer risk outdoors for the population is 3.8 10?4, and t he mean value of the external radiation hazard index obtained in this study is 0.48, which is consistent with the world average. A low dose of radiation will not pose a risk to the population and biota in the studied area.


2020 ◽  
Vol 108 (11) ◽  
pp. 913-921
Author(s):  
Nesli Bingöldağ ◽  
Pelin Otansev

AbstractThe concentrations of 226Ra, 232Th, 40K and 137Cs radionuclides in soil samples collected from 323 different regions of Nevşehir province were determined by using a gamma spectrometer with an HPGe detector. The mean gamma activity concentrations (ranges) of 226Ra, 232Th, 40K and 137Cs for districts were determined as 49.45 (7.40–193.90), 54.08 (<2.8–122.50), 698.43 (37.67–1370.20) and 8.26 (0.10–52.60) Bq kg−1, respectively. The mean activity concentrations of 226Ra, 232Th and 40K were higher than the world mean value. According to Kolmogorov–Smirnov test, distributions of 226Ra, 232Th and 137Cs show log-normal distributions. Whereas, 40K shows normal distribution. The mean radium equivalent activity was 181.68 Bq kg−1 which is lower than the recommended maximum value of 370 Bq kg−1. The mean external terrestrial gamma dose rate was found to be 85.12 nGy h−1. The calculated external hazard value was 0.49 and within the acceptable limit which is less than unity (Hex ≤ 1). Thermo Scientific RadEye NBR detector was used to determine environmental gamma dose rates. The gamma dose rates were measured at 445 points at a height of 1 m from land surface. The mean outdoor gamma dose rate (range) was found as 150.13 (50–480) nGy h−1. This mean value was found higher than world mean value. The fact that most of the Nevşehir province is based on volcanic rocks explains why the gamma dose rates are high.


Author(s):  
C. P. Ononugbo ◽  
O. Azikiwe ◽  
G. O. Avwiri

Radioactivity distribution and transfer factor (TF) in plants are crucial parameters used to assess radioactive contamination in the environment, impact of soil radioactivity on agricultural crops and its risks to humans.  The root crop cassava (Manihot esculenta) provides about 50 percent of the calories consumed in Nigeria. Gamma - ray spectroscopy was used to measure activity concentrations of 226Ra, 232Th and 40K in cassava root and soil. The average activity concentration of 40K, 226Ra and 232Th in cassava was 565.31± 13.17, 21.89±5.94 and 817.28±2.52 Bqkg-1 respectively. The mean activity concentration   40K, 226Ra and 232Th in soil range from 92.07±35.08 to 689.28±14.35 Bqkg-1with a mean value of 413.64±21.22 Bqkg-1, 5.37 ± 8.90 to 64.93 ± 7.23 Bqkg-1 with a mean value of 54.43 ± 3.22 and BDL to 928.15 ± 2.36 Bqkg-1 with a mean value of 561.67 ± 2.21 Bqkg-1. The transfer values for 226Ra, 232Th and 40K were in the range of 0 to 1.81, 0 to 3.41 and 0.68 to 4.5 respectively. The high value of transfer factor for 40k may be due to its importance in plant growth, fertilization and adaptability of plant to environmental pressures. It may have also been enhanced by the application of NPK fertilizers in those farms. Thorium showed the highest mean transfer factor which may be due to its higher accumulation in soil and higher uptake by plants (Figure 3). The average transfer factors of 226Ra (0.99) < 40K (1.55) < 232Th (1.66) show that although activity concentration of the natural radioisotopes in the area under study are high, the rate at which they are transferred to cassava are still moderate.  The average values of radium equivalent activity (Raeq), absorbed dose rate (D), annual effective dose rate (AEDE), internal hazard index and excess life cancer risk (ELCR) are 1009.27 Bqk-1, 346.50 nGyh-1, 1.51 mSvy-1, 2.78 and 3.92 x 10-3 for respectively. These values were higher than their corresponding permissible values of 370Bqk-1, 55nGyh-1, 1.0 mSvy-1, 1.0 and 0.29 x 10-3 respectively. The mean values of Hex and Hin are greater than unity and may, therefore, constitute a significant radiological health risk. The mean annual gonad dose estimated value of 2943.90 mSvy-1  was above the world acceptable value of 300 mSvy-1 and the annual effective dose in all the samples except in few locations as shown in Figure 2, exceeded the safe value of 1.0 mSvy-1. The use of soil from these farms and the crops may constitute a threat to the bone marrow and general health conditions of the inhabitants.


2020 ◽  
Vol 2020 ◽  
pp. 1-11
Author(s):  
Lucia Nyiva Munyao ◽  
Daniel Kipngetich Ketui ◽  
Calford Otieno ◽  
Margaret Wairimu Chege

Construction sand is naturally polluted with radionuclides of terrestrial origin. In this study, specific activities of 238U, 232Th, and 40K in 30 sand samples collected along the Ekalakala River, Machakos County, Kenya, were measured using a high-purity germanium γ-ray spectrometer. The specific activities ranged between 9.7 Bqkg−1 and 24.0 Bqkg−1, 11.5 Bqkg−1 and 26.2 Bqkg−1, and 820 Bqkg−1 and 1850 Bqkg−1 for 238U, 232Th, and 40K, respectively. While the mean specific activities for 238U and 232Th were less than half of the world average values of 33 Bqkg−1 and 45 Bqkg−1, respectively, the average specific activity of 40K was significant since it was three times the global mean value of 420 Bqkg−1. A calculated absorbed radiation dose rate for the sand varied between 46.8 nGyh−1 and 94.2 nGyh−1 with a mean of 68.5 ± 13.3 nGyh−1. This is not significantly different from the world average dose rate of 60 nGyh−1 for geological samples. The AEDR and Hex had maximum values of 0.29 mSvy−1 and 0.52, respectively, both within the recommended limits of radiation exposure for members of the general public. Based on these results, the sand from Ekalakala River does not pose significant health implication to the sand harvesters as well as the inhabitants of the houses constructed using this sand.


2019 ◽  
pp. 1-9
Author(s):  
M. Onwuka ◽  
C. P. Ononugbo

Radiometric survey of the granitic quarry site at Ishiagu and its environment was done using two radiation monitors and geographical positioning system (GPS) for GIS mapping. In-situ measurement of exposure rate was carried out following the international standard organizational standard between May 2018 and June 2019. The measured average exposure rates ranged from 0.010± 0.002 to 0.038 ± 0.003 mRh-1 with mean value of 0.026 ±0.005 mRh-1. The estimated outdoor absorbed dose rate ranged from 87.0 to 330.6 nGyh-1 with mean value of 228.38 nGyh-1. The equivalent dose rate ranges from 0.84 to 3.20 mSvy-1 with mean value of 2.21 mSvy-1. The mean annual effective dose equivalent (AEDE) calculated was 0.28 mSvy-1 while the mean excess lifetime cancer risk (ELCR) was 0.98 x 10-3. The estimated annual effective dose to different organs showed that the testes have the highest annual effective  dose of 0.191 mSvy-1 followed by ovaries and kidney of 0.135 and 0.139 mSvy-1 respectively while the liver has the lowest annual effective  dose of 0.103 mSvy-1. The radiation contour map of the area showed the distribution of radiation of high and low areas. The result showed that the radiation exposure rate and its associated radiological risk parameters exceeded the safe limits prescribed by ICRP and also the values reported in literatures. However, these values may not constitute acute health risk but long term exposure of residents and workers may be detrimental to their health. Therefore adequate monitoring of this quarry site is necessary to checkmate the exposure rate and provide some protective measures for quarry workers.


2017 ◽  
Vol 27 (5) ◽  
pp. 587-596 ◽  
Author(s):  
Kaliprasad C. Shivanandappa ◽  
Narayana Yerol

The present paper discusses the systematic study on gamma dose rate, radon exhalation, radium content in soil and sediment and radon concentration in water of Hemavathi River environments. The Gamma dose rate in the air in the study area varied from 98 to 202 nGy h−1 with mean value 145 nGy h−1. The measured dose rate was above the world and Indian average. The mean value of radium activity in soil and sediment was found to be 366.61 and 328.36 mBq kg−1, respectively. The mean value of radon in soil and sediment was found to be 373.90 and 334.90 Bq m−3, respectively. The radon concentration of water ranges from 0.20 to 1.60 kBq m−3 with an average value of 0.67 kBq m−3. The radon in water contributes to dosage in stomach and lungs. The effective doses of radon were calculated and compared with international recommended values. The results show that sediment and water are safe to use for construction and drinking purpose.


Author(s):  
Noriyuki Kuwano ◽  
Masaru Itakura ◽  
Kensuke Oki

Pd-Ce alloys exhibit various anomalies in physical properties due to mixed valences of Ce, and the anomalies are thought to be strongly related with the crystal structures. Since Pd and Ce are both heavy elements, relative magnitudes of (fcc-fpd) are so small compared with <f> that superlattice reflections, even if any, sometimes cannot be detected in conventional x-ray powder patterns, where fee and fpd are atomic scattering factors of Ce and Pd, and <f> the mean value in the crystal. However, superlattices in Pd-Ce alloys can be analyzed by electron microscopy, thanks to the high detectability of electron diffraction. In this work, we investigated modulated superstructures in alloys with 12.5 and 15.0 at.%Ce.Ingots of Pd-Ce alloys were prepared in an arc furnace under atmosphere of ultra high purity argon. The disc specimens cut out from the ingots were heat-treated in vacuum and electrothinned to electron transparency by a jet method.


1987 ◽  
Vol 26 (06) ◽  
pp. 253-257
Author(s):  
M. Mäntylä ◽  
J. Perkkiö ◽  
J. Heikkonen

The relative partition coefficients of krypton and xenon, and the regional blood flow in 27 superficial malignant tumour nodules in 22 patients with diagnosed tumours were measured using the 85mKr- and 133Xe-clearance method. In order to minimize the effect of biological variables on the measurements the radionuclides were injected simultaneously into the tumour. The distribution of the radiotracers was assumed to be in equilibrium at the beginning of the experiment. The blood perfusion was calculated by fitting a two-exponential function to the measuring points. The mean value of the perfusion rate calculated from the xenon results was 13 ± 10 ml/(100 g-min) [range 3 to 38 ml/(100 g-min)] and from the krypton results 19 ± 11 ml/(100 g-min) [range 5 to 45 ml/(100 g-min)]. These values were obtained, if the partition coefficients are equal to one. The equations obtained by using compartmental analysis were used for the calculation of the relative partition coefficient of krypton and xenon. The partition coefficient of krypton was found to be slightly smaller than that of xenon, which may be due to its smaller molecular weight.


1968 ◽  
Vol 20 (01/02) ◽  
pp. 044-049 ◽  
Author(s):  
B Lipiński ◽  
K Worowski

SummaryIn the present paper described is a simple test for detecting soluble fibrin monomer complexes (SFMC) in blood. The test consists in mixing 1% protamine sulphate with diluted oxalated plasma or serum and reading the optical density at 6190 Å. In experiments with dog plasma, enriched with soluble fibrin complexes, it was shown that OD read in PS test is proportional to the amount of fibrin recovered from the precipitate. It was found that SFMC level in plasma increases in rabbits infused intravenously with thrombin and decreases after injection of plasmin with streptokinase. In both cases PS precipitable protein in serum is elevated indicating enhanced fibrinolysis. In healthy human subjects the mean value of OD readings in plasma and sera were found to be 0.30 and 0.11, while in patients with coronary thrombosis they are 0.64 and 0.05 respectively. The origin of SFMC in circulation under physiological and pathological conditions is discussed.


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