scholarly journals A Method for Identification and Assessment of Radioxenon Plumes by Absorption in Polycarbonates

Sensors ◽  
2021 ◽  
Vol 21 (23) ◽  
pp. 8107
Author(s):  
Dobromir Pressyanov ◽  
Pavel Stavrev
Keyword(s):  
Computer Modeling ◽  
Gamma Spectrometry ◽  
Activity Concentration ◽  
Retrospective Evaluation ◽  
Time Intervals ◽  
Activity Concentrations ◽  
Quantitative Estimates ◽  
Consecutive Time ◽  
The Moment ◽  
True Values

A method for the retrospective evaluation of the integrated activity concentration of 133Xe during radioxenon plumes and the moment of the plume’s center is proposed and explored by computer modeling. The concept is to use a specimen of polycarbonate material (a stack of Makrofol N foils of thickness 120 µm and 40 µm in 1 L non-hermetic Marinelly beaker) that is placed in the environment or in a controlled nuclear or radiopharmaceutical facility. On a regular basis or incidentally, the specimen may be retrieved and gamma spectrometry in two consecutive time intervals with durations of 8 h and 16 h is performed. To assess the performance of the method, 133Xe plumes of various integrated activity concentrations and with a duration of up to 10 h are simulated and analyzed, assuming that the measurement starts with a delay of up to one day after the moment of the plume center. It is found that the deviation between the estimates by the method and their true values are within a few percent. Depending on the delay, events of integrated 133Xe activity concentration 250–1000 Bq h m−3 might be qualitatively identified. At levels >10,000 Bq h m−3, the uncertainty of the quantitative estimates might be ≤10%.

Applying in-Situ and Laboratory-based Gamma Spectrometry to Determine Activity Concentration and Distribution of 40K, 226Ra and 232Th in Abeokuta, Southwest Nigeria

2021 ◽  
Vol 14 (4) ◽  
pp. 323-331
Keyword(s):  
Gamma Spectrometry ◽  
Activity Concentration ◽  
Risk Level ◽  
Primordial Radionuclides ◽  
Activity Concentrations ◽  
Nuclear Security ◽  
Southwest Nigeria ◽  
Average Activity ◽  
The City

Abstract: The applications of radionuclides are potential sources of health risk and also a concern in the area of nuclear security. It is therefore imperative to determine the presence of the different radionuclides present in the environment at all times, because it is necessary to control and assess the risk level in the environment. The present study compares activity concentrations of the primordial radionuclides 40K, 226Ra and 232Th obtained from laboratory gamma spectrometry measurements with the activity concentrations of the radionuclides as obtained from in-situ measurements. Soil samples were randomly collected from nineteen different points within Abeokuta city ensuring good coverage of the city area. A mobile gamma spectrometry system was used to collect gamma spectra measurements in the field. The obtained values are presented. The ranges of activity concentrations for 40K, 226Ra and 232Th have been found to be 113 – 1975, 5 – 128 and 181 – 3284 Bqkg-1, respectively for laboratory gamma spectrometry and 104 – 1312, 31 – 121 and 104 – 2578 Bqkg-1, respectively for in-situ gamma spectrometry measurements. This study showed that the average activity concentrations of the primordial radionuclides in Abeokuta were much higher than worldwide averages of 400, 35 and 30 Bqkg-1 for 40K, 226Ra and 232Th, respectively. From both methods, 232Th is seen to be the major contributor to the environmental radioactivity of Abeokuta. Good correlations also were deduced between the activity concentration results obtained from laboratory and in-situ gamma spectrometry, which therefore implies a significant relationship between the two methods used in the study. Keywords: In-situ gamma, Gamma spectrometry, Activity concentration, Radionuclides.

Measurement of radon concentration in kindergartens and schools in Nis, Serbia

2019 ◽  
Vol 17 (2) ◽  
pp. 191-197
Author(s):  
Vesna Manic ◽  
Goran Manic ◽  
Branko Radojkovic ◽  
Dusica Vucic ◽  
Dragoslav Nikezic ◽  
...  
Keyword(s):  
Standard Deviation ◽  
Gamma Spectrometry ◽  
Radon Concentration ◽  
Hpge Detector ◽  
Activity Concentration ◽  
Average Value ◽  
Activity Concentrations ◽  
Log Normal ◽  
The Town ◽  
Log Normal Distribution

In this study, the activity concentration of radon, 222Rn, in kindergartens and schools in the town of Nis, Serbia, was explored. The method of active charcoal was applied. The measurements were carried out by gamma - spectrometry with HPGe detector. The results belong to the range of 15 Bq/m3 - 256 Bq/m3, with an average value of 59.7 Bq/m3 and a standard deviation of 25.3 Bq/m3. It was shown that data are distributed according to the log-normal distribution, and that is no correlation between indoor 222Rn concentrations and the activity concentrations of radium, 226Ra, in the soil.

scholarly journals New Approach for the Determination of Radiological Parameters on Hardened Cement Pastes with Coal Fly Ash

Materials ◽  
2021 ◽  
Vol 14 (3) ◽  
pp. 475
Author(s):  
Ana María Moreno de los Reyes ◽  
José Antonio Suárez-Navarro ◽  
Maria del Mar Alonso ◽  
Catalina Gascó ◽  
Isabel Sobrados ◽  
...  
Keyword(s):  
Fly Ash ◽  
Activity Concentration ◽  
Gamma Ray ◽  
Coal Fly Ash ◽  
Cementitious Materials ◽  
New Method ◽  
Supplementary Cementitious Materials ◽  
Hardened Cement ◽  
Cement Pastes ◽  
Activity Concentrations

Supplementary cementitious materials (SCMs) in industrial waste and by-products are routinely used to mitigate the adverse environmental effects of, and lower the energy consumption associated with, ordinary Portland cement (OPC) manufacture. Many such SCMs, such as type F coal fly ash (FA), are naturally occurring radioactive materials (NORMs). 226Ra, 232Th and 40K radionuclide activity concentration, information needed to determine what is known as the gamma-ray activity concentration index (ACI), is normally collected from ground cement samples. The present study aims to validate a new method for calculating the ACI from measurements made on unground 5 cm cubic specimens. Mechanical, mineralogical and radiological characterisation of 28-day OPC + FA pastes (bearing up to 30 wt % FA) were characterised to determine their mechanical, mineralogical and radiological properties. The activity concentrations found for 226Ra, 212Pb, 232Th and 40K in hardened, intact 5 cm cubic specimens were also statistically equal to the theoretically calculated values and to the same materials when ground to a powder. These findings consequently validated the new method. The possibility of determining the activity concentrations needed to establish the ACI for cement-based materials on unground samples introduces a new field of radiological research on actual cement, mortar and concrete materials.

scholarly journals Test spectra experimental construction for evaluating gamma-spectrometry computer codes for the 235U determination

2014 ◽  
Vol 29 (suppl.) ◽  
pp. 1-7 ◽  
Author(s):  
Konstantinos Karfopoulos ◽  
Dimitrios Karangelos ◽  
Marios Anagnostakis ◽  
Simos Simopoulos
Keyword(s):  
Gamma Spectrometry ◽  
Energy Region ◽  
Environmental Samples ◽  
Activity Concentration ◽  
Germanium Detector ◽  
Computer Code ◽  
High Background ◽  
Spectrometry Analysis ◽  
Background Continuum ◽  
Concentration Levels

The determination of 235U in environmental samples from its 185.72 keV photons may require the deconvolution of the multiplet photopeak at ~186 keV, due to the co-existence of the 186.25 keV photons of 226Ra in the spectrum. Successful deconvolution depends on many parameters, such as the detector characteristics, the activity concentration of the 235U and 226Ra in the sample, the background continuum in the 186 keV energy region and the gamma-spectrometry computer code used. In this work two sets of experimental test spectra were constructed for examining the deconvolution of the multiplet photopeak performed by different codes. For the construction of the test spectra, a high-resolution low energy germanium detector was used. The first series consists of 140 spectra and simulates environmental samples containing various activity concentration levels of 235U and 226Ra. The second series consists of 280 spectra and has been derived by adding 137Cs, corresponding to various activity concentration levels, to specific first series test spectra. As the 137Cs backscatter edge is detected in the energy region of the multiplet photopeak at ~186 keV, this second series of test spectra tests the analysis of the multiplet photopeak in high background continuum conditions. The analysis of the test spectra is performed by two different g-spectrometry analysis codes: (a) spectrum unix analysis code, a computer code developed in-house and (b) analysis of germanium detector spectra, a program freely available from the IAEA. The results obtained by the two programs are compared in terms of photopeak detection and photopeak area determination.

scholarly journals Evaluation of Plasmatic Levels of Negative and Positive Acute Hepatic Phase Proteins in Patients who Underwent Major Surgery

2019 ◽  
Vol 70 (11) ◽  
pp. 3947-3953
Author(s):  
Laura Nicolescu ◽  
Bogdan Totolici ◽  
Ovidiu Bedreag ◽  
Cristian Nicolescu ◽  
Alin Mihu
Keyword(s):  
Acute Phase ◽  
Acute Phase Proteins ◽  
Major Surgery ◽  
P Value ◽  
Time Intervals ◽  
Reactive Protein ◽  
Pearson Coefficient ◽  
Simultaneous Decrease ◽  
Correlation Tests ◽  
The Moment

The acute hepatic phase response is defined as a reaction that includes hepatic synthesis of proteins, consisting in the increase of some proteins called positive acute phase proteins and the simultaneous decrease of others called negative acute phase proteins. This study describes this hepatic reaction, based on a series of consecutive determinations, at three different time intervals (right before a major surgery event, 24 and 48 hours after the intervention), of the plasmatic levels of transferrin, albumin, fibrinogen and C reactive protein (CRP). Subsequently, the data was analyzed using Jamovi 2019, version 0.9. The inferential statistics consisted in calculating an ANOVA test that compared the values at 24 hours and 48 hours versus the values right before the major surgery. The results were validated by calculating the p value (p[0.05) as well as conducting correlation tests by determining the Pearson coefficient which shows the values of CRP, fibrinogen, transferrin and albumin are independent of each other and do not interact. The multiple ANOVA comparative test reveals the lack of interaction between the values of determined proteins, regardless of the moment of determination.

In situ gamma spectrometry using portable HPGe detector. Radiological characterization and environmental surveillance around an operating nuclear power plant. Possibilities and limits

2021 ◽  
Author(s):  
Jose Angel Corbacho ◽  
A Baeza
Keyword(s):  
Power Plant ◽  
Nuclear Power Plant ◽  
Gamma Spectrometry ◽  
Nuclear Power ◽  
Power Plants ◽  
Activity Concentration ◽  
Versatile Tool ◽  
Ge Detector ◽  
Radiological Characterization

Abstract In situ technique for measuring radionuclides in the soil using a portable Ge detector is a highly versatile tool for both the radiological characterization and for the monitoring of operating nuclear power plants. The main disadvantage of this technique is related to the lack of knowledge of the geometry of the source whose activity concentration is to be determined. However, its greatest advantage is the high spatial representability of the samples and the lower time and resource consumption than gamma spectrometry lab measurements. In this study, the possibilities and limits offered by in situ gamma spectrometry with a high resolution gamma portable detector in two common uses are shown: First, the radiological background characterization and its relationship with the geology of an area of 2700 km2 are assessed; Secondly, its potential for monitoring man-made activity concentration in soils located around an operating nuclear power plant in Spain for surveillance purposes is evaluated. Finally, high accuracy radiation maps have been prepared from the measurements carried out. These radiation maps are essential tools to know the radioactive background of an area, especially useful to assess artificial radioactive deposits produced after a nuclear accident or incident.

Refinement of waste phosphogypsum from Prahovo, Serbia: characterization and assessment of application in civil engineering

Clay Minerals ◽  
2020 ◽  
Vol 55 (1) ◽  
pp. 63-70
Author(s):  
Josip I. Išek ◽  
Lazar M. Kaluđerović ◽  
Nikola S. Vuković ◽  
Maja Milošević ◽  
Ivana Vukašinović ◽  
...  
Keyword(s):  
Inductively Coupled Plasma ◽  
Activity Concentration ◽  
Construction Materials ◽  
Road Construction ◽  
Radiation Hazard ◽  
Emission Spectrometry ◽  
Insoluble Residue ◽  
Radium Equivalent Activity ◽  
Activity Concentrations ◽  
Two Samples

AbstractTwo samples collected from the phosphogypsum deposits of the chemical products industry Elixir Prahovo (Serbia) were subjected to a recrystallization experiment performed over several repeated cycles. In these tests, phosphogypsum was separated into recrystallized (purified) gypsum, insoluble residue and supernatant. Both raw phosphogypsum and recrystallized gypsum were examined using inductively coupled plasma optical emission spectrometry, X-ray diffraction and scanning electron microscopy with energy-dispersive spectrometry. The activity concentrations of 238U, 235U, 226Ra, 210Pb, 232Th and 40K were investigated using γ-ray spectrometry. Based on the activity concentration results, a number of radiometric parameters were calculated for the original and recrystallized phosphogypsum (i.e. radium equivalent activity, γ indices for construction materials, α index and external and internal hazard indices). Raw phosphogypsum samples showed greater mean activity concentration levels of 238U and 226Ra than the international recommended limits, while the recrystallized gypsum demonstrated notably lower activity concentrations for these two isotopes. The activity concentration of 226Ra in recrystallized gypsum is ~6 times lower than in raw phosphogypsum. Therefore, recrystallized gypsum does not present a radiation hazard when used as a building material, while raw phosphogypsum meets the requirements only for road construction materials.

MEASUREMENT OF RADON SOIL GAS IN AND AROUND BHARATHINAGARA, MANDYA DISTRICT

2019 ◽  
Vol 187 (1) ◽  
pp. 83-87
Author(s):  
T S Shashikumar ◽  
S Revanna ◽  
M N Ramachandra ◽  
G V Ashok ◽  
C Ningappa ◽  
...  
Keyword(s):  
Solid State ◽  
Moisture Content ◽  
Activity Concentration ◽  
Geometric Mean ◽  
Winter Season ◽  
Mean Value ◽  
Summer Season ◽  
Soil Gas ◽  
Activity Concentrations ◽  
The World

Abstract Radon activity concentration in soil gas has been studied in and around Bharathinagara, Mandya district (12° 13|| N and 77° 20|| E) using Solid State Nuclear Track Detectors with Twin cup dosimeter. The activity concentration of 222Rn in soil gas was studied at two depths. Radon in soil gas was found to increase with depth and decrease with increase in moisture content of the soil. Radon in soil gas was found to be higher in winter season which varies from 0.22 ± 0.01 to 1.31 ± 0.01 kBq/m3 with a Geometric mean value of 0.56 ± 0.01 kBq/m3 in 1 m depth and lower radon soil gas was found to be 0.16 ± 0.01 to 0.60 ± 0.01 kBq/m3 with a Geometric mean value of 0.30 ± 0.01 kBq/m3 in 0.5 m depth during summer season. The activity concentrations of radon soil gas from in and around Bharathinagara are lower compared to those in other parts of the world.

Radiological health assessment due to gamma radiation levels of natural radioactivity of soil in vicinity of Nichahoma lignite belt, Kashmir Valley

2016 ◽  
Vol 104 (6) ◽  
Author(s):  
Mudasir Ashraf ◽  
C. Anu Radha ◽  
Shakeel Ahmad ◽  
Sajad Masood ◽  
Rayees Ahmad Dar ◽  
...  
Keyword(s):  
Correlation Analysis ◽  
Gamma Radiation ◽  
Natural Radioactivity ◽  
Activity Concentration ◽  
Health Assessment ◽  
Kashmir Valley ◽  
Radioactive Nuclides ◽  
Activity Concentrations ◽  
Measured Dose ◽  
Radiological Health

AbstractThe measurements of activity concentrations in soil of the lignite belt and soil of the villages surrounding the lignite belt have been carried out in order to present the radiological health hazards due to gamma radiation levels of the soil to general public. A low- background Pb-shielded gamma spectroscopic counting assembly utilizing NaI(Tl) detector was employed for the measurements. The activity concentration of radionuclides have been determined and compared with the international and national recommended values. A correlation analysis was also performed in order to predict the contribution of the respective nuclides towards the measured dose rate and to the find the existence of these radioactive nuclides together in the study area.

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