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Uranium hexafluoride (UF6) is a significant concern for material accountancy and verification in the international safeguards community. Verification of the contents of UF6 cylinders is generally attempted with gamma spectroscopy but the current methods assume a uniform, homogeneous UF6 mass distribution within the cylinder. In this work, it was found experimentally and confirmed via modeling, that under an external heat load (the sun), the UF6 and its daughter products undergo fractionation in the cylinder. This fractionation of the UF6 and daughter products can cause an errant measurement of the enrichment of the cylinder when using the current verification methods. [ABSTRACT FROM AUTHOR]

The radioactivity concentrations in soil and medicinal plants from the Western Ghat region of India were determined using NaI(Tl) gamma spectrometry. The mean activity of 232Th, 226Ra and 40K in soil was found to be 15.0 ± 0.9 Bq kg−1, 35.8 ± 2.1 Bq kg−1 and 65.1 ± 2.2 Bq kg−1. In medicinal plants, the mean activity was found to be 9.3 ± 1.1 Bq kg−1, 28.4 ± 2.8 Bq kg−1 and 76.3 ± 3.7 Bq kg−1, respectively. The calculated transfer factors from soil to plant range from 0.70 to 2.88, 0.49 to 1.64 and 0.37 to 1.53 for 40K, 226Ra and 232Th, respectively. The mean transfer factor of 40K is greater than that of 226Ra and 232Th, showing a substantial increase of 40K in the plant by root uptake. The estimated average yearly effective dosage for the age group of 15 years and older in the study is much lower than the world average, whereas, for the age group of 5 years, the Mesua ferrea, Moringa oleifera, and Piper betle medicinal plant are above the recommended word average of 0.3 mSv y−1 for an individual as reported UNSCEAR, 2000. As a result, the consumption of medicinal plants does not pose a substantial health risk and is radiologically safe for intake by people aged 15 years and above, but not to individuals under the age of 5. The possible impact of natural radiation on a human has been assessed by calculating the hazard parameters and all values within the internationally recommended limits. The impact of soil physico-chemical properties on soil-medicinal plant transfer factor was assessed. The study will serve as a baseline data on the transfer of radionuclides from the soil to medicinal plants and from medicinal plants to human as well as guidelines on the development of herbal drugs for future pharmacological and phytochemical studies. [ABSTRACT FROM AUTHOR]

This study investigates the levels of natural and artificial radioactivity in rice samples collected from various local markets in Islamabad, Pakistan. The 226Ra, 232Th, and 40K activity concentrations were measured through gamma-ray spectrometry with a NaI(Tl) detector. The average activity concentrations were 1.67 ± 1.19 Bq kg−1 for 226Ra, 3.31 ± 1.83 Bq kg−1 for 232Th, and 88.51 ± 11.65 Bq kg−1 for 40K. Calculated radium equivalent (Raeq) values ranged from 7.35 to 18.08 Bq kg−1, with a mean value of 11.11 Bq kg−1, all below the permissible maximum of 370 Bq kg−1. The absorbed dose rates ranged from 6.85 to 16.39 nGy h−1, with an average of 10.64 nGy h−1, falling below the acceptable limit of 51 nGy h−1. The outdoor and indoor radiation hazard indices (Hex and Hin) had mean values of 0.03, both below the threshold value of one. The external and internal hazard indices (Iγ and Iα) were both 0.088, also below the critical value of one. The excess lifetime cancer risk (ELCR) ranged from 0.28 to 0.11, with a mean value of 0.18, which is less than the critical value of one. Overall, the radioactivity levels in the analyzed rice samples are within the acceptable limits set by the International Commission on Radiological Protection and are below global averages. These results offer important insights into the radiological safety of rice consumption in the study area. [ABSTRACT FROM AUTHOR]

This study was carried out to evaluate the activity concentration of natural radioisotopes that exist in different incense (bakhour) samples collected randomly from the local markets in Baghdad, Iraq. Very few data have been published that focused on the concentrations of natural radionuclides in incense. The analysis was done using a high-purity germanium detector. The results indicate the existence of a wide range of radioactivity contents among the different tested products as follows; 9.5 to 53.1 Bq.kg-1 for the 226Ra, 3.5 to 21.2 Bq.kg-1 for 232Th and 332 to 1717 Bq.kg-1 for 40K. The mean radioactivity concentrations for the nine samples were 26.5, 10.4, and 794 Bq.kg-1 for 226Ra, 232Th, and 40K respectively. Prediction of the annual intake of incense for a single consumer was difficult to achieve, therefore two scenarios were considered and the findings concluded that incense smoke is safe from a radiological exposure perspective for the presence of the investigated radionuclides.

Abstract Neutron tomography is gaining popularity particularly in cultural heritage research, for non-destructively analysing the inner structure of bulk metal artefacts, such as bronzes, but the induced temporary decay radiation is often considered as a drawback. However, this delayed gamma-emission can be put to good use: by performing gamma spectroscopy after neutron tomography, the interior elemental composition of artefacts can be obtained “for free”. Inspired by this, we propose a ray-tracing approach to non-invasively quantify both interior geometry and elemental composition using only a single neutron tomography experiment. This strategy aligns well with both the aim for efficient use of neutron beam time and the expectation from curators and conservators for minimal neutron irradiation. Here, we outline the core principle of this method, demonstrate the extent of its quantification capability on bulk objects of known composition by fusing neutron tomography and delayed-gamma spectroscopy data sets. We also showcase its practical application on an ancient solid-cast Indonesian bronze statuette, by which we gain insights into how the pristine inner bronze segregated into a different composition than the surrounding shell. Similarly, the method allows us to quantify the composition of a hidden offering in the statuette that consecrates the bronze for worship purposes.

Neutron tomography is gaining popularity particularly in cultural heritage research, for non-destructively analysing the inner structure of bulk metal artefacts, such as bronzes, but the induced temporary decay radiation is often considered as a drawback. However, this delayed gamma-emission can be put to good use: by performing gamma spectroscopy after neutron tomography, the interior elemental composition of artefacts can be obtained "for free". Inspired by this, we propose a ray-tracing approach to non-invasively quantify both interior geometry and elemental composition using only a single neutron tomography experiment. This strategy aligns well with both the aim for efficient use of neutron beam time and the expectation from curators and conservators for minimal neutron irradiation. Here, we outline the core principle of this method, demonstrate the extent of its quantification capability on bulk objects of known composition by fusing neutron tomography and delayed-gamma spectroscopy data sets. We also showcase its practical application on an ancient solid-cast Indonesian bronze statuette, by which we gain insights into how the pristine inner bronze segregated into a different composition than the surrounding shell. Similarly, the method allows us to quantify the composition of a hidden offering in the statuette that consecrates the bronze for worship purposes. [ABSTRACT FROM AUTHOR]

The raw materials of cement contain radioactive elements that come from natural sources. Members of the decay chains of uranium, thorium, and potassium radioisotope 40K are the primary sources of this radioactivity. The natural radionuclide concentration levels in cement differ greatly depending on different geographic areas. To estimate the radionuclides concentration in cement specimens from twelve diverse Pakistani companies, gamma-ray spectroscopy analysis was used in the study. 226Ra, 232Th, and 40K had activity concentration levels ranging from 18.08 to 43.18 Bq/kg, 16.73 to 23.53 Bq/kg, and 14.24 to 315.22 Bq/kg, respectively. The United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR) threshold for the 226Ra was surpassed by five of the studied samples. The indoor and outdoor dose rates as well as different radiological health hazard indices were also examined. The Indoor Absorbed Dosage (Din) for some of the samples exceeded the permissible limit. These samples also had a high Indoor Effective Lifetime Cancer Risk (ELCR) factor, which makes them unsafe for interior construction purposes. The outdoor dosages as well as the hazard indices were well within the permitted ranges. The outdoor ELCR factor is low for all the cement brands, which makes them safe for exterior construction purposes. The findings were compared with published data from other countries around the globe. Finally, a thorough statistical analysis was performed and Pearson's Correlation Coefficient (r) exhibited a very strong correlation between the different outdoor and indoor radiological health hazard indices. [ABSTRACT FROM AUTHOR]

This review paper provides a comprehensive analysis of radiation shielding concrete, covering its properties, design, evaluation, and applications. It begins with an introduction, stating the objective and scope. The paper explores radiation shielding basics, including ionizing radiation, shielding principles, and materials used for shielding. Concrete's properties relevant to shielding, radiation attenuation mechanisms, and factors affecting its efficiency are discussed. Different types of radiation shielding concrete are examined, along with their applications. The design and formulation of shielding concrete, including mix proportions, optimization techniques, and quality control, are presented. Evaluation methods and standards are discussed. Lastly, challenges, future directions, and emerging technologies are outlined. This review paper serves as a valuable resource for professionals involved in radiation shielding. The review on radiation shielding concrete highlighted its effectiveness in attenuating ionizing radiation, emphasizing material composition, density, and thickness as key design factors. Evaluation methods, such as gamma spectroscopy and Monte Carlo simulations, are discussed, demonstrating its versatile applications in nuclear facilities, healthcare, and space exploration. [ABSTRACT FROM AUTHOR]

The study was carried out to evaluate the radioactivity concentrations of 40K, 232Th and 238U in five maize samples collected from maize farms within Ekiti State, Nigeria. The activity concentration measurements were determined using n -- type co-axial HPGe detectors for the state. The activity concentrations were found to vary from 994.67 - 2457.01 Bq Kg-1 for 40K, 32.84 - 91.88 Bq kg-1 for 232Th and 43.21 - 97.77 Bq kg-1 for 238U respectively. The annual effective dose to individuals from the consumption of the Maize was estimated on the basis of the measured radionuclides content in the food crop which ranged between 0.41 and 1.51 m Svy-1 respectively. The value 1.04 m Svy-1 were obtained for the state as the mean total annual effective dose. The mean excess life time cancer risk was also calculated to be 2.06x10-9. The value was compared with the internationally acceptable limits and found to be far less to the maximum permissible dose of 1.0 x10-3 recommended for the public by the United Nations Scientific Committee on the Effects of Atomic Radiation. Hence, the maize was found to be safe for human consumption. [ABSTRACT FROM AUTHOR]

The occurrence of sand and dust storms (SDS) in Iran has raised many concerns about the possibility of environmental and public health hazards caused by dust particles and pollutants existed in these particles. Therefore, the purpose of this study was to investigate the possibility of contamination of surface soil, river sediments, and roadside deposits with radioactive materials, especially depleted uranium (DU) in the areas affected by SDS. The radioactive activity of the samples was measured by gamma spectroscopy with a high-purity germanium detector. The average activity concentrations of 226Ra, 232Th, and 40 K were 11.19, 8.05, and 76.05 Bq/kg. The average ratio of 238U/235U was 89 indicating the possibility of the presence of DU in the soil samples. The average values of Rm (the share of 235U in total uranium) and DUm were 0.55% (lower than natural uranium, 0.72) and 33% (indicating the presence of 33% DU on average in the samples). Based on 238U/226Ra activity, two samples (S11 and S12) should be considered as DU-contaminated. Almost the obtained results for all radiological risk indices showed lower values than the world average and the possibility of creating a low risk for working people, residents, visitors, and travelers passing through these areas. [ABSTRACT FROM AUTHOR]

The processing of nuclear pulse signals based on deep learning (DL) requires a well-labeled data set. However, the current energy spectrometers can only give users the final results, and do not allow manual labeling during the pulse signal collection process. The presented (GaSim) is a Python-based gamma pulse simulator of the raw detector electrical output signal with excellent customization capabilities. It allows customization of gamma pulse signal parameters from various aspects, making it versatile and useful for a wide range of detectors. Additionally, it provides the required labels for each generated electrical pulse at specified positions, enabling the creation of datasets for DL development.

Current radiation dosimeters sometimes face accuracy limitations or provide only cumulative doses over long periods. To contribute to this area, we developed a portable monitor that measures the energy spectrum and dose of gamma rays in real time. To achieve this, we used an improved sequential Bayesian estimation algorithm. The dose rate was then derived from the energy spectrum by applying a flux-to-dose conversion coefficient. The monitor consists mainly of a CsI(Tl) scintillator and a multi-pixel photon counter (MPPC). In developing this device, we focused on striking a balance between measurement accuracy, ease of use, and portability. As an essential aspect of the research, we investigated the influence of the CsI(Tl) crystal size on the performance of the monitor to determine an optimal size. This was accomplished by calculating the detection efficiency and energy resolution through experimental measurements using standard gamma-ray sources and simulations using MCNP5. Within the scope of the research, detector response functions were created for each crystal size for an energy range of 10 keV to 3 MeV. Considering an optimal balance of detection efficiency and energy resolution alongside a compact size suitable for portable applications, the crystal measuring 2.6 × 2.6 × 1.3 cm3 was deemed preferable.

This research aimed to determine the activity concentration of 226Ra in the natural radioactivity of the surface water of the Maritsa River, Türkiye. The gamma spectrometric analysis was conducted by using 3′′ × 3′′ NaI(Tl) and (HPGe) detector. Since the direct measurement method could not acquire reliable results, the mean activity concentration of 226Ra was calculated as 0.62 Bq L−1 with the "standard addition method". The mean values of the gross alpha/beta activities and the total radium alpha activity concentration were measured. The results are 0.013 Bq L−1, 0.304 Bq L−1, and 0.014 Bq L−1 respectively. [ABSTRACT FROM AUTHOR]

The current scenario of radioactive waste management requires innovative and automated solutions to ensure its effectiveness and safety. In response to this need, the Proximity Imaging System for Sort and Segregate Operations (PI3SO) project was proposed. It is a gamma radiation proximity scanner system for radioactive waste with the primary goal of speeding up some aspects of the waste management cycle while reducing direct human operations. The system will provide proximity imaging for hot-spot finding and spectral analysis for radiological characterization, enabling semiautomatic recognition, sorting and separation of radioactive waste. The core of the proposed scanning system consists of an array of 128 CsI(Tl) scintillators, 1 cm3 size, coupled with silicon photomultipliers (SiPMs), installed on a motorized bridge sliding along a suitable table in order to scan the materials under investigation. [ABSTRACT FROM AUTHOR]

Vineyards hold considerable soil variability between regions and plots, and there is frequently large soil heterogeneity within plots. Clay content in vineyard soils is of interest with respect to soil management, environmental monitoring, and wine quality. However, spatially resolved clay mapping is laborious and expensive. Gamma-ray spectrometry (GS) is a suitable tool for predicting clay content in precision agriculture when locally calibrated, but it has scarcely been tested site-independently and in vineyards. This study evaluated GS to predict clay content with a site-independent calibration and four machine learning algorithms (Support Vector Machines, Random Forest, k-Nearest Neighbors, and Bayesian regulated neuronal networks) in eight vineyards from four German vine-growing regions. Clay content in the studied soils ranged from 62 to 647 g kg−1. The Random Forest calibration was most suitable. Test set evaluation revealed good model performance for the entire dataset with RPIQ = 4.64, RMSEP = 56.7 g kg−1, and R2 = 0.87; however, prediction quality varied between the sites. Overall, GS with the Random Forest model calibration was appropriate to predict the clay content and its spatial distribution, even for heterogeneous geopedological settings and in individual plots. Therefore, GS is considered a valuable tool for soil mapping in vineyards, where clay content and product quality are closely linked. [ABSTRACT FROM AUTHOR]

The assessment of the radioactivity level and associated risks has been performed for the mangrove plants. Twenty-five mangrove samples were collected from the Abu Fasi, Marsa Shaab, and Sowmaa mangroves in the Marsa Shaab area of the Egyptian Red Sea coast. The activity concentration values of the nuclides 226Ra, 232Th, and 40K for samples collected from sediments associated with the mangrove environments were measured. The specific activities in mangrove samples obtained in the Abu Fasi region varied as follows: 15± 0.8 Bq.kg-1 to 42± 2.1 Bq.kg-1 for 226Ra, 10± 0.5 Bq.kg-1 to 39± 1.9 Bq.kg-1 for 232Th, and 103± 5.2 Bq.kg-1 to 340± 17 Bq.kg-1 for 40K. Additionally, the activity concentrations of the mangrove samples collected from Marsa Shaab and Sowmaa mangrove areas ranged as follows: 28± 1.4 to 56± 2.8 Bq.kg-1 for 226Ra, 18± 0.9 to 58± 2.9 Bq.kg1 for 232Th, and 164± 8.2 to 531± 26.5 Bq.kg-1 for 40K. Moreover, the mangrove samples collected from the Sharm el El Madfea area showed activity concentrations ranging as follows: 25± 1.3 to 52± 2.6 Bq.kg-1, 15± 0.8 to 61± 3 Bq.kg-1, and 250± 9.1 to 583± 29.2 Bq.kg-1 for 226Ra, 232Th, and 40K, respectively. The highest average values were observed in samples collected from Marsa Shaab and Sowmaa mangroves for the 226Ra and 232Th. However, the highest average value for 40K was measured in samples collected from the Sharm El Madfea area. The radiation hazard calculations for the collected mangrove samples showed much lower values than the criterion and worldwide recommended limits. [ABSTRACT FROM AUTHOR]

Nuclear physics experiments use specially designed modular units that process signals from radiation detectors and provide information on the nature of these processes. These units, called nuclear electronics, form the basis of nuclear spectrometry systems in medicine, dosimetry, cosmic ray research, and other sources of ionizing radiation. The article describes the creation of an electrical measurement circuit for the ΔE-E method of recording and identifying lightly charged particles using the MultiSim program.By using this program, a spectrometric amplifier, a single-channel analyzer, and a coincidence circuit were simulated using modern microelectronic components. Based on the simulated circuit, a prototype of a spectrometric amplifier was created. The signal obtained from the created prototype coincides with the simulated one. The obtained data indicate that the simulated scheme can be used for experiments in nuclear physics for the identification of lightly charged particles, as well as in other areas where there is a need for nuclear spectroscopy. [ABSTRACT FROM AUTHOR]

The study assessed natural radioactivity in Rohtak and Jind districts, Haryana, India. Concentrations of radionuclides in soil and building materials were measured using gamma-ray spectroscopy. The "Canister Technique" was employed to estimate radon mass exhalation and surface exhalation rates. Results showed low radiation doses from soil radioactivity, with activity concentrations ranging from 3.7 to 51.7 Bq/kg for radium, 7.3 to 96 Bq/kg for thorium, and 52.2 to 585 Bq/kg for potassium. The findings also calculated radium equivalent activity, annual effective dose rate, hazard indices, and excess life time cancer risk. This research highlights the importance of understanding natural radioactivity for assessing environmental radiation exposure. [ABSTRACT FROM AUTHOR]

Natural radionuclides, particularly 238U, 232Th, and 40K are the main sources of radiation exposure. Therefore, their detection is key to radiation safety measurement, among others. Therefore, this study is aimed at assessing the natural radioactivity concentrations of 238U, 232Th, and 40K of 15 sediment and water samples from selected locations in Funtua town, Katsina state, Nigeria using gamma spectroscopy NaI (TI) and CR-39 Can detectors respectively. Data obtained show that, the activity concentrations in the sediment samples were found to range between 11.50 - 61.89, 7.15 - 69.46, and 646.01 - 1368.33 Bq/kg with average activity concentrations of 37.15, 35.66, and 914.73 Bq/kg for 238U,232Th, and 40K, respectively. These average values exceeded the worldwide values of 25, 25, and 370 Bq/kg respectively. In water samples, the values of 238U ranged from 0.20 to 36.78 Bq/L (̅x = 16.12 𝐵𝑞/𝐿); activity concentration values for 232Th radionuclide ranged from 2.75 Bq/L to 76.90 Bq/L (̅x = 11.71 𝐵𝑞/𝐿) and that of 40K radionuclide ranged from 42.28 Bq/L to 179.95 Bq/L (̅x = 111.81 𝐵𝑞/𝐿) respectively. These values are higher than the recommended value of 30000 g/L as reported by the EPA. The average activity concentrations of 238U,232Th, and 40K were found to be higher in the sediment samples than in the water samples. The estimated total annual effective dose AED in the water sample was found to be less than the worldwide values of 0.1mSv/y or 0.2 to 0.8. The excess life cancer risk ELCR of radon in the water ranged from 0.0983×10-4 to 1.8084×10-4 with a mean value of 0.7949×10-4. This value is less than the worldwide limit of 1.0×10-4. Therefore, the groundwater (wells) in Funtua town is said to be safe based on the effects of the activity concentrations of these natural primordial radionuclides and radon on the environment. However, the need for continuous monitoring should be a priority. [ABSTRACT FROM AUTHOR]

Diagnostics are critical on the path to commercial fusion reactors, since measurements and characterisation of the plasma is important for sustaining fusion reactions. Gamma spectroscopy is commonly used to provide information about the neutron energy spectrum from activation analysis, which can be used to calculate the neutron flux and fusion power. The detection limits for measuring nuclear dosimetry reactions used in such diagnostics are fundamentally related to Compton scattering events making up a background continuum in measured spectra. This background lies in the same energy region as peaks from low-energy gamma rays, leading to detection and characterisation limitations. This paper presents a digital machine learning Compton suppression algorithm (MLCSA), that uses state-of-the-art machine learning techniques to perform pulse shape discrimination for high purity germanium (HPGe) detectors. The MLCSA identifies key features of individual pulses to differentiate between those that are generated from photopeaks and Compton scatter events. Compton events are then rejected, reducing the low energy background. This novel suppression algorithm improves gamma spectroscopy results by lowering minimum detectable activity (MDA) limits and thus reducing the measurement time required to reach the desired detection limit. In this paper, the performance of the MLCSA is demonstrated using an HPGe detector, with a gamma spectrum containing americium-241 (Am-241) and cobalt-60 (Co-60). The MDA of Am-241 improved by 51% and the signal to background ratio improved by 49%, while the Co-60 peaks were partially preserved (reduced by 78%). The MLCSA requires no modelling of the specific detector and so has the potential to be detector agnostic, meaning the technique could be applied to a variety of detector types and applications. [ABSTRACT FROM AUTHOR]

Abstract The assessment of natural radionuclides in soil samples from artisanal gold mine sites in Iperindo, Nigeria was conducted using different analysis methods. Soil samples collected across three locations and within a control area were analyzed using well-calibrated gamma spectroscopy fitted with a sodium iodide detector. The average activity concentrations (ranges) of 238U, 232Th, and 40 K were found to be 61.55 ± 13.97 (33.40–87.00) Bqkg−1, 72.65 ± 16.83 (41.90–105.10) Bqkg−1, and 1134.99 ± 142.24 (720.50–1722.10) Bqkg−1, respectively for the mining areas and 15.26 ± 6.96 (10.90–20.10) Bqkg−1, 21.46 ± 9.35 (17.40–25.30) Bqkg−1, and 381.04 ± 51.27 (280.30–511.70) Bqkg−1, respectively for the control locations. The average activity concentrations of the radionuclides assessed were above the worldwide permissible limits for the Iperindo mining areas and below the worldwide average for the control areas. The investigation also assessed various radiological parameters, encompassing the radium equivalent, dose rate, annual effective dose rate, internal and external hazard indices, alpha and gamma indices, annual gonadal equivalent, and excess lifetime cancer risk. The recorded values for mine locations were 252.83 Bqkg−1, 119.98 nGyh−1, 0.15 mSvy−1, 0.85 Bqkg−1, 0.68 Bqkg−1, 0.31 Bqkg−1, 1.89 Bqkg−1, 850.23 μSvy−1, and 0.52 $$\times$$ × 10−3, respectively. Except for the radium equivalent, external and internal hazard risks, and the alpha index, which were notably below the recommended threshold, all the other radiological parameters exceeded the globally advised limits. All the radiological parameters from the control areas were below the worldwide average values.

The activity concentrations of 226Ra, 232Th and 40K were determined in 43 soil samples collected from 0 to 10 cm and 10 to 50 cm depths of Niška Banja region, Serbia, using a low background gamma spectroscopy with 3″ × 3″ NaI(Tl) scintillation detector. The mean absorbed dose rate of 0–10 cm and 10–50 cm depth soil were 66.1 and 60.4 nGy/h, respectively which was close to UNSCEAR worldwide value. The radium equivalent and annual effective dose effect were lower than the permissible level. Therefore, there is no significant radiological risk from the soil to residents living in this region. [ABSTRACT FROM AUTHOR]

AbstractThe pebble bed reactor is a unique reactor design due to its capacity for continuous multipass circulation of the fuel elements, without causing interruption to reactor operation, with the assistance of the burnup measurement system. Such a system necessarily requires an accurate knowledge of the burnup of each fuel pebble upon ejection from the core so as to inform the reloading decision and to ensure that no pebble exceeds the regulated discharge burnup limit at any point following reinsertion into the reactor core. In this work, we conceptualize, develop, and demonstrate a machine learning–based fuel burnup prediction framework leveraging advanced modeling and simulation capabilities.At its core, machine learning regression models are learned from simulated data to establish the correlation among the irradiated fuel composition (hence burnup), the gamma leakage spectrum, and the gamma spectroscopy results. Sensitivity analysis is conducted to quantify the impact of unknown design parameters, such as fuel enrichment, and irradiation environment, including power density, temperature, and neighboring materials, on the prediction accuracy of various supervised regression algorithms.The effects of a short cooldown period on machine learning prediction accuracy are also investigated. A test data set is used to validate that the data generation methodology proposed in this work successfully results in a machine learning model capable of interpolating its prediction of burnup onto a much wider range of irradiation conditions than were explicitly represented in the training database. The inclusion of a cooldown period of just 2 h leads to a prediction root-mean-square error of <5 MWd/kgU when the fuel enrichment is known and <9 MWd/kgU otherwise. [ABSTRACT FROM AUTHOR]

This article discusses the development of machine learning algorithms for pulse shape discrimination in an organic scintillation phoswich detector. The researchers successfully identified gamma radiation signals from two scintillating components using a single-readout phoswich detector. Their Boosted Decision Tree algorithm demonstrated a maximum discrimination power in the 950 keV region, providing an efficient solution for enhancing radiation detection capabilities. The study highlights the potential of organic scintillators in detecting particles like dark matter and neutrinos. The document also discusses the challenges and future improvements for the phoswich detector. The raw data supporting the conclusions of the article will be made available by the authors. [Extracted from the article]

The current work uses a high-purity germanium (HPGe) gamma detector to measure radionuclides in the soil in Kordofan, Sudan. This experimental investigation was required to determine the activities of soil samples and detect the radiation hazard indices at three selected locations in Kordofan, which include 238U, 232Th, 226Ra, and 40K using gamma-ray spectrometry. The assessment of radium equivalent (Req) was determined to be between 25.12 Bq/kg to 293.03 Bq/kg. However, the external and internal hazard indices Hex and Hin were less than the permissible limit of 1. The possible radiological health risk in the soil was estimated using the absorbed dosage rate of the area under study in the range of 13.06 to 94.4 nGy/hour. It is revealed that the range of radiation annual effective absorbed dose rates is 0.03 to 0.116 mSv/year. The activity concentrations of these radionuclides were measured to be fairly consistent with the data that had been reported globally. [ABSTRACT FROM AUTHOR]

The assessment of natural radionuclides in soil samples from artisanal gold mine sites in Iperindo, Nigeria was conducted using different analysis methods. Soil samples collected across three locations and within a control area were analyzed using well-calibrated gamma spectroscopy fitted with a sodium iodide detector. The average activity concentrations (ranges) of 238U, 232Th, and 40 K were found to be 61.55 ± 13.97 (33.40–87.00) Bqkg−1, 72.65 ± 16.83 (41.90–105.10) Bqkg−1, and 1134.99 ± 142.24 (720.50–1722.10) Bqkg−1, respectively for the mining areas and 15.26 ± 6.96 (10.90–20.10) Bqkg−1, 21.46 ± 9.35 (17.40–25.30) Bqkg−1, and 381.04 ± 51.27 (280.30–511.70) Bqkg−1, respectively for the control locations. The average activity concentrations of the radionuclides assessed were above the worldwide permissible limits for the Iperindo mining areas and below the worldwide average for the control areas. The investigation also assessed various radiological parameters, encompassing the radium equivalent, dose rate, annual effective dose rate, internal and external hazard indices, alpha and gamma indices, annual gonadal equivalent, and excess lifetime cancer risk. The recorded values for mine locations were 252.83 Bqkg−1, 119.98 nGyh−1, 0.15 mSvy−1, 0.85 Bqkg−1, 0.68 Bqkg−1, 0.31 Bqkg−1, 1.89 Bqkg−1, 850.23 μSvy−1, and 0.52 × 10−3, respectively. Except for the radium equivalent, external and internal hazard risks, and the alpha index, which were notably below the recommended threshold, all the other radiological parameters exceeded the globally advised limits. All the radiological parameters from the control areas were below the worldwide average values. [ABSTRACT FROM AUTHOR]

Nuclear radiation from radioactive elements may cause genetic abnormalities or causes dangerous diseases such as cancer. For this reason, it is essential to measure food contamination with radionuclides, especially seafood prepared from areas contaminated with industrial pollution. In this case, it is necessary to calculate the risk of developing cancer and determine the permissible amount of their consumption. In this work, the specific activity of 4 radioactive elements 226Ra, 232Th, 40K, and 137Cs was measured in 18 meat and skin samples, including 3 species of farmed fish, such as Cyprinus carpio, Pomadasys kaakan and Epinephelus multinotatus from the Persian Gulf, and 2 species of shrimp, including the marine Metapenaeus ensis and the farmed Litopenaeus vannamei. The results indicate that the specific activities of radionuclides in seafood, skins were higher than in meat, and the maximum concentration of 226Ra, 232Th, and 40K was observed in the skins of Cyprinus carpio (8.34 Bq/kg), Metapenaeus ensis (31.61 Bq/kg) and Epinephelus multinotatus (404.26 Bq/kg). For all samples, the amount of 137Cs was below the detectable limit. [ABSTRACT FROM AUTHOR]

Natural radionuclides, particularly 238U, 232Th, and 40K are the main sources of radiation exposure. Therefore, their detection is key to radiation safety measurement, among others. Therefore, this study is aimed at assessing the natural radioactivity concentrations of 238U, 232Th, and 40K of 15 sediment and water samples from selected locations in Funtua town, Katsina state, Nigeria using gamma spectroscopy NaI (TI) and CR-39 Can detectors respectively. Data obtained show that, the activity concentrations in the sediment samples were found to range between 11.50 - 61.89, 7.15 – 69.46, and 646.01 – 1368.33 Bq/kg with average activity concentrations of 37.15, 35.66, and 914.73 Bq/kg for 238U,232Th, and 40K, respectively. These average values exceeded the worldwide values of 25, 25, and 370 Bq/kg respectively. In water samples, the values of 238U ranged from 0.20 to 36.78 Bq/L ( ); activity concentration values for 232Th radionuclide ranged from 2.75 Bq/L to 76.90 Bq/L ( ) and that of 40K radionuclide ranged from 42.28 Bq/L to 179.95 Bq/L ( ) respectively. These values are higher than the recommended value of 30000 g/L as reported by the EPA. The average activity concentrations of 238U,232Th, and 40K were found to be higher in the sediment samples than in the water samples. The estimated total annual effective dose AED in the water sample was found to be less than the worldwide values of 0.1mSv/y or 0.2 to 0.8. The excess life cancer risk ELCR of radon in the water ranged from 0.0983×10-4 to 1.8084×10-4 with a mean value of 0.7949×10-4. This value is less than the worldwide limit of 1.0×10-4. Therefore, the groundwater (wells) in Funtua town is said to be safe based on the effects of the activity concentrations of these natural primordial radionuclides and radon on the environment. However, the need for continuous monitoring should be a priority.

This study focuses on measuring the levels of naturally occurring radioactivity in the soil of Swabi, Khyber Pakhtunkhwa, Pakistan, as well as the associated health hazard. Thirty (30) soil samples were collected from various locations and analyzed for 226Ra, 232Th, and 40K radioactivity levels using a High Purity Germanium detector (HPGe) gamma-ray spectrometer with a photo-peak efficiency of approximately 52.3%. The average values obtained for these radionuclides are 35.6 ± 5.7 Bqkg−1, 47 ± 12.5 Bqkg−1, and 877 ± 153 Bqkg−1, respectively. The level of 232Th is slightly higher and 40K is 2.2 times higher than the internationally recommended limit of 30 Bqkg−1 and 400 Bqkg−1, respectively. Various parameters were calculated based on the results obtained, including Radium Equivalent (Raeq), External Hazard (Hex), Absorbed Dose Rate (D), Annual Gonadal Equivalent Dose (AGDE), Annual Effective Dose Rate, and Excess Lifetime Cancer Risk (ELCR), which are 170.3 ± 24 Bqkg−1, 0.46 ± 0.06 Bqkg−1, 81.4 ± 2.04 nGy h−1, 582 ± 78.08 μSvy−1, 99.8 ± 13.5 μSv Gy−1, and 0.349 ± 0.04, respectively. These values are below the limits recommended by the United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR) in 2002. This study highlights the potential radiation threats associated with natural radioactivity levels in the soil of Swabi and provides valuable information for public health and safety.

This study was carried to assess the radiological health risks associated with occupational exposure to natural radioactivity in some of ceramic raw materials and building materials. The concentrations of Ra-226, Th-232, and K-40 were measured using a gamma ray spectrometer equipped with a hyper pure germanium (HPGe) detector. In the present work, the mean values of Ra-226 for fly ash, bauxite, ceramic colors and marble are higher than the world average value of 35 (Bq/kg). The mean values of Th-232 for clay, fly ash, bauxite, ceramic colors, marble and granite are higher than the world average value of 30 (Bq/kg). For K-40, field spar, ceramic colors, marble and granite have mean values that higher than the world average value of 400 (Bq/kg). The radiological health hazard parameters such as radium equivalent activity, absorbed dose rate, annual effective dose rate, excess life time cancer risk, external hazard index and internal hazard index were calculated based on the mean values of these radionuclides. The maximum values of radium equivalent activity, absorbed dose rate, annual effective dose rate, excess life time cancer risk, external hazard index and internal hazard index were 3299.98 (Bq/kg), 4429.658 (nGy/h), 3.703 (mSv/y), 12.962, 8.92 and 15.97; respectively. Also, the equivalent and effective doses due to occupational exposure were calculated with Dose Conversion Factors for External Exposure (DFEXT code).

Preliminary validation of isotope dilution gamma spectroscopy (IDGS) for plutonium concentration measurement was investigated in this study. A high 239Pu abundance plutonium solution was used as an isotope dilution agent. By studying the changes in isotopic abundance of 241Pu and 239Pu before and after adding the dilution agent to plutonium working sample, and combining it with high-purity germanium gamma spectrometry, a method for measuring plutonium concentration and isotopic composition using IDGS technology was established. In this experiment, the concentration and isotopic composition of the plutonium diluent working standard and the plutonium working sample were accurately calibrated by the controlled potential coulometry and mass spectrometry separately. Different gamma ray pairs with similar energy from appropriate energy regions were selected to calculate the isotopic abundance ratio, and the efficiency calibration was performed on this gamma ray pairs. The optimal volume and concentration of the plutonium gamma measurement standard solution were explored and determined. Using IDGS technology, the test samples with plutonium concentration of 2 g/L in the nitric acid plutonium solution and the abundance range of 239Pu from 57% to 70% were measured. The results show that within 1.5 h, the RSD of IDGS technology for plutonium concentration measurement is ≤0.68%, and the measured values are in good agreement with those measured by the Coulomb method, with deviations from 0.3% to 2.3%. When measuring the isotopic composition, the RSD of 241Pu/239Pu is ≤0.46%, and the RSD of 239Pu abundance is ≤0.66%. The RSD of the measurement results for two parallel samples of the same plutonium sample is ≤0.98%. With the optima dilution ratio range of 1∶4 to 4∶1, a small amount of dilution agent could achieve good consistency with the Coulomb method measurement results, but beyond this dilution ratio range, the deviation of the measurement results from the Coulomb method is larger. These results indicate that using domestically high-quality plutonium samples to prepare diluent working standards, adopting portable medium-high energy gamma spectrometry to directly measure liquid plutonium sources, and selecting the 241Pu/239Pu atomic ratio to determine plutonium concentration by the IDGS technology is feasible. It simplifies the sample preparation process, shortens the measurement time, and reduces the analysis costs. Compared with the isotope dilution mass spectrometry, IDGS technology is easier to operate and has a shorter analysis cycle. Compared with the hybrid K-edge method, it can simultaneously measure both plutonium concentration and isotope composition. Therefore, this technology can be used for rapid measurement of plutonium concentration in spent fuel solutions, providing technical support for the management of nuclear materials in our spent nuclear fuel reprocessing plants in the future.

We developed machine learning algorithms for distinguishing scintillation signals from a plastic-liquid coupled detector known as a phoswich. The challenge lies in discriminating signals from organic scintillators with similar shapes and short decay times. Using a single-readout phoswich detector, we successfully identified γ radiation signals from two scintillating components. Our Boosted Decision Tree algorithm demonstrated a maximum discrimination power of 3.02 ± 0.85 standard deviation in the 950 keV region, providing an efficient solution for self-shielding and enhancing radiation detection capabilities.

Spectroscopic analysis of radiological materials has been historically limited to radiological labs with older or less advanced scientific instrumentation. The development of double-walled cells (DWCs) at the Savannah River National Laboratory (SRNL) has enabled Pu-bearing compounds to be removed from radiological laboratories and studied in our radiologically clean spectroscopy laboratory with state-of-the-art instrumentation. In this manuscript, we discuss the contributions of DWCs that have allowed the application of Raman spectroscopy, diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS), diffuse reflectance spectroscopy (DRS) in the shortwave infrared, and gamma spectroscopy at SRNL. Significant advances have been made in the understanding of the thermal decomposition of Pu(III) and Pu(IV) oxalates, alpha-induced damage to the PuO2 crystal lattice, and the effect of calcination temperatures on the quality of PuO2. These techniques have enabled methods to conduct PuO2 age dating since last calcination and estimate the calcination temperature with Raman spectroscopy and DRS. Additional spectroscopic information measured with DRIFTS has enabled the observation of the evolution of carbon species with calcination temperature, while gamma spectroscopy provides information on age dating since last purification. [ABSTRACT FROM AUTHOR]

Soil samples from vegetable farmland in densely populated wards of Nepal were analyzed for natural radionuclide levels, employing a NaI(Tl) 3" × 3" gamma detector. The study aimed to evaluate the causes of radiation risk, attributing it to soil contamination resulting from the rapid urbanization and concretization that followed the earthquake in 2015. The activity concentration of radium-226, thorium-232, and potassium-40 and the ranges observed are 2.080±0.084–33.675±1.356 Bq kg - 1 , 17.222±0.198–119.949±1.379 Bq kg - 1 , and 11.203 ± 0.325–748.828±21.716 Bq kg - 1 , respectively. The average values obtained for hazard indices are as follows: radium equivalent activity (82.779 Bq kg - 1 ), absorbed dose rate (36.394 nGy h - 1 ), annual effective dose equivalent (0.045 mSv yearr - 1 ), gamma index (0.291), external hazard index (0.224), internal hazard index (0.253), excess lifetime cancer risk (0.159), annual gonadal dose equivalent (243.278 mSv year - 1 ), alpha index (0.054), and activity utilization index (0.716). However, in most places, thorium-232 concentration is greater than those of the world average and recommended values. In specific locations such as Ward 4 in Baluwatar, the soil was found to have concentrations of Ra 226 and K 40 exceeding recommended limits. Despite this localized concern, the overall analysis of hazard indices across the studied areas revealed that most values were within permissible limits. This suggests that, on a broader scale, radiation exposure may not be a significant concern in the investigated regions. Nonetheless, the study recommends regular monitoring in additional locations to ensure a comprehensive and ongoing assessment of radiation levels. [ABSTRACT FROM AUTHOR]

In order to trace the origin of Particulate Matter (PM) in Korea, the research was conducted to analyze the nuclide of PM samples. To analyze the PM sample, we performed Backtracking Analysis and Gamma spectroscopy. PM is affected by the size of the atmospheric mixing layer height and the air flow according to the air mass. The air flow of the 2 seasons (summer and autumn) was predicted by using Hysplit (backtracking analysis). And the radioactivity of nuclides in the PM sample collected from the measuring site is confirmed using gamma spectroscopy and radioactivity calculation method. Takuya (J Nuclear Radiochem Sci, 8(1):5–9, 2007) As a result of analyzing samples collected in 2 seasons, it was confirmed that the radioactivity of specific nuclides changed according to the season and was affected by air flow. In conclusion, the origin of PM can be estimated by confirming the change in PM and nuclides. [ABSTRACT FROM AUTHOR]

The radioactivity concentrations of Naturally Occurring Radioactive Materials (NORM) i.e., 226Ra, 232Th, and 4 K in various chemical fertilizers being used in the agricultural soil of Pakistan were determined utilizing gamma spectrometry by employing a High Purity Germanium (HPGe) detector. The radioactivity concentrations of 226Ra, 232Th, and 4 K extended from 2.58 ± 0.8–265.7 ± 8.8 Bq kg−1, 1.53 ± 0.14–76.6 ± 1.07 Bq kg−1 and 36.5 ± 1.34–15606.7 ± 30.2 Bq kg−1 respectively. The radiological hazard parameters such as internal and external indices and annual effective dose rates were calculated, while excessive lifetime cancer risk factors for the indoor and outdoor areas were found in the range from 0.3 × 10−3 to 10.723 × 10−3 and 0.03 × 10−3 to 2.7948 × 10−3 of most fertilizers, however, some values were slightly higher than the UNSCEAR (The United Nations Scientific Committee on the Effects of Atomic Radiation) recommended values for potash-containing fertilizers such as MOP (Muriate of Potash).