This study presents a comprehensive assessment of natural and anthropogenic radioactivity in industrialized soils from two key zones in Bordj Bou Arreridj and M'sila, eastern Algeria. Utilizing high-resolution gamma-ray spectrometry with a high-purity germanium (HPGe) detector, the investigation determined the activity concentrations of 226Ra, 232Th, and 40K radionuclides. The obtained mean activity concentrations were 20.6 ± 1.4, 27.3 ± 0.7, and 464 ± 9 Bq·kg−1, respectively. Notably, 137Cs was detected only in the Bordj Bou Arreridj zone at trace levels, attributed to historical radioactive fallout. The air absorbed dose rates yielded a mean value of 45.6 ± 1.4 nGy·h−1, while the outdoor annual effective doses remained significantly below the International Commission on Radiological Protection (ICRP) limit of 1 mSv·y−1. All calculated radiological indices were within safety limits, indicating no significant public health hazards. These results provide a critical radiological characterization of Algerian industrial soils, offering essential baseline data for environmental monitoring and the development of radiation protection standards in Algeria.
Scattered and random coincidences in brain PET imaging introduce significant noise and degrade resolution. Current correction algorithms for these effects are complex and computationally intensive. Fully connected neural network (FCNN) offers strong feature learning capabilities, versatility, and flexibility. Given that the coincidence data in brain PET imaging has relatively few features, FCNNs are well-suited to rapidly establish the relationship between coincidence data information and coincidence event types.
Reliable thermodynamic data for cesium compounds are essential to predict fission products behavior during severe nuclear reactor accidents. This study establishes the physicochemical properties of cesium chromate (Cs2CrO4), cesium ferrate (Cs2FeO4), and its decomposition product CsFeO2 through combined experimental and first-principles approaches. High-purity samples were synthesized by solid-state reaction and characterized using powder X-ray diffraction (XRD), thermogravimetric-differential scanning calorimetry (TG-DSC), and in-situ high-temperature XRD measurements up to 1050 degrees C. First-principles DFT and quasi-harmonic phonon calculations provided complementary insights into vibrational and electronic properties. Cs2CrO4 crystallizes in an orthorhombic Pnma structure and undergoes one-step decomposition at temperatures of about 950 degrees C. Cs2FeO4 exhibited a rapid dehydration at about 97 degrees C, transformed to CsFeO2 starting from 170 degrees C, transiently reabsorbed oxygen at a temperature range of 400 degrees C to 800 degrees C, and finally decomposed to Fe2O3 above 1086 degrees C. The computed heat capacities reproduced the experimental Cp up to 750 K (476.85 degrees C), while the imaginary phonon modes reveal dynamic instabilities in ferrate phases. An electronic-structure analysis revealed band gaps of about 3.0 eV for Cs2CrO4 and about 1.2 eV for Cs2FeO4, while CsFeO2 displays metallic behavior. By linking these results to severe accident scenarios, this work clarifies how decomposition thresholds, phase stability ranges, and redox sensitivity of cesium compounds govern their volatility, transport, and deposition in reactor containment. The validated dataset provides critical input for source-term databases (e.g., ECUME - effective chemistry database of fission products under multiphase reaction) and severe accident codes such as MELCOR and ASTEC, thereby improving the predictive accuracy of cesium release and radiological safety assessments.
This study investigates the feasibility of using a low-cost, rapidly deployable UAV-based system for gamma radiation monitoring. A UAV equipped with a GammaRAE II R dosimeter was used to conduct radiation surveys at the T & rcaron;ebsko site, Czech Republic. The system mapped spatial variations in gamma radiation and identified hotspots, showing strong correlation with previous high-resolution surveys of the area. Data analysis, conducted using open-source software, included altitude corrections, spatial interpolation, and statistical techniques to visualize radiation distribution patterns. Peak gamma dose rate values reached 1.276 mu Sv/h (altitude-normalized), with 11 locations showing statistically significant elevation (Z-score >3). While the system's sensitivity is lower than professional-grade equipment, it demonstrated sufficient accuracy for preliminary surveys and rapid assessments. This approach, combining consumer-grade technology with open-source tools, provides a practical solution for environmental monitoring, emergency response, and educational applications, particularly valuable in resource-limited or time-sensitive scenarios. The results validate the potential of affordable radiation monitoring systems as complementary tools to traditional high-cost methods.
Using a NaI(Tl) detector and the gamma spectrometry technique, 18 soil samples were taken from the Al-Hindiya District in Karbala, Iraq, in order to measure the activity concentrations of 40K, 226Ra, and 232Th. The results demonstrated that these radionuclides' activity concentrations in the soil samples varied from 329 to 498 Bq/kg, 18.9 to 28.2 Bq/kg, and 8.2 to 13.1 Bq/kg, respectively. These levels, especially for 226Ra and 232Th, were lower than the global median values published by UNSCEAR (2000) and comparable to those in nearby locations. In order to carry out a more thorough investigation, a sample of dates, water from the Euphrates River, and sandy soil from dredging were also gathered and their inherent radioactivity examined. The sandy soil contained activity concentrations of 40K, 226Ra, and 232Th of 271 Bq/kg, 13.1 Bq/kg, and 7.3 Bq/kg, respectively. The values in the water samples were, respectively, 2.13, 0.06, and less than the minimum detectable activity (MDA) in Bq/L. The readings for the date sample were, respectively, 380, 1.5, and MDA Bq/kg. With an average of 41 mu Sv/y, the outdoor annual effective dose caused by these radionuclides in the soil varied between 34.6 mu Sv/y and 48.6 mu Sv/y, which is consistent with values found in the literature and international regulations. Thus, it can be said that the natural radioactivity levels in this area do not pose a threat to the inhabitants.
