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Evaluation of natural radioactivity levels in soil samples of Al-Hindiya District, Karbala, Iraq

Wed, 25 Mar 2026 00:00:00 GMT

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 μSv/y, the outdoor annual effective dose caused by these radionuclides in the soil varied between 34.6 μSv/y and 48.6 μSv/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.

Feasibility of low-cost UAV-based gamma radiation surveys for environmental monitoring: A case study from the Třebsko Site, Czech Republic

Wed, 25 Mar 2026 00:00:00 GMT

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 Třebsko 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 μSv/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.

Physicochemical properties of cesium chromate and ferrate: Experimental and first-principles insights for severe accident source-term modeling

Wed, 25 Mar 2026 00:00:00 GMT

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°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°C. Cs2FeO4 exhibited a rapid dehydration at about 97°C, transformed to CsFeO2 starting from 170°C, transiently reabsorbed oxygen at a temperature range of 400°C to 800°C, and finally decomposed to Fe2O3 above 1086°C. The computed heat capacities reproduced the experimental Cp up to 750 K (476.85°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.

Integrating X-ray fluorescence and X-ray computed tomography for comprehensive analysis of historical ceramics from the Kraków Upland

Tue, 21 Oct 2025 00:00:00 GMT

This study presents the application of non-destructive analytical techniques, particularly X-ray fluorescence (XRF) and X-ray computed tomography (XCT), to characterize archaeological pottery from medieval and early post-medieval periods. Five pottery samples from three nearby sites located in the Kraków Upland (Kraków district, Poland) were analyzed to explore their material composition, structural properties, and manufacturing techniques. The XRF analysis revealed a detailed elemental composition, and the results obtained matched those of the XRF analysis of source clay deposits in the same microregion. Archaeological pottery contains 3–4 times more silicon than clay deposits, which can be explained by the addition of sandy temper. The level of aluminum in ceramics is similar to that of Al in clay deposits. We also observe a slightly higher contribution of iron in our pottery samples compared to the clay pottery samples. The XCT analysis provided high-resolution, three-dimensional (3-D) images of internal structures, such as inclusions and voids, enabling further investigation into tempering and preparation methods. Segmentation and void analyses demonstrated variations in clay refinement, inclusion distribution, and porosity, indicating a range of manufacturing techniques from rudimentary to advanced practices. The integration of XRF and XCT results underscored the complementary strengths of these techniques despite their respective limitations, such as challenges in mineral differentiation in XCT and voxel resolution constraints. The findings highlight the importance of combining chemical and structural analyses to gain a comprehensive understanding of archaeological ceramics. This study advances the methodological approaches for pottery analysis and offers broader implications for archaeological research and heritage conservation.

Estimation rate of total alpha particle emission in blood and milk of women living in city center and rural areas of Al-Muthanna Governorate-Iraq

Tue, 21 Oct 2025 00:00:00 GMT

Iraq has long suffered from environmental pollution due to past wars, specifically the first and second Gulf Wars in 1990 and 2003. Al-Muthanna governorate, as part of Iraq, was directly affected by these conflicts and has experienced environmental and epidemiological changes that may increase the risk of cancer in the region. For this reason, monitoring the alpha particles emissions in human blood and milk was of significant importance. This study aims to estimate the total alpha particle emission rate (Eα) in blood and milk samples of women residing in different environments (rural area and city center) of Al-Muthanna Governorate, using CR-39 detectors. The results revealed that the highest, lowest, and mean Eα values in milk samples from city center and rural areas were (1.63, 0.68, and 1.10 mBq/ml) and (1.59, 0.56, and 1.01 mBq/ml), respectively. The maximum, minimum, and average Eα values in the city center and rural areas blood samples were (2.05, 0.90, and 1.31 mBq/ml) and (1.61, 0.66, and 1.12 mBq/ml), respectively. The findings indicated that the Eα in milk and blood samples in rural areas were lower than in the city center, which may be attributed to the reduced anthropogenic and military activities in rural areas.

Beam diagnostic analysis of the accelerator systems commissioning line in the Early Neutron Source Project

Tue, 21 Oct 2025 00:00:00 GMT

This study summarizes the final stage of work done at NCBJ in conjunction with the ongoing large scale International Fusion Materials Facility: Demo Oriented Neutron Source (DONES) project. DONES will be a neutron source with sufficiently high intensity and spectral range of neutrons generated in D-T reactions to enable the generation of structural defects in materials at the level of 20 dpa. Currently existing devices cannot achieve these properties. Our work optimized proton and deuteron beam delivery from a commissioned quadruple accelerator to the entry point of a planned high energy beam transport (HEBT) section in the DONES system. We considered two variants: a beam led by solenoids and a beam led by quadruples. Additional specifications required the insertion of a diagnostic plate that could not be separated by any other component, such us a solenoid or a quadruple. Using beam dynamics calculations, we delivered each beam from the radio frequency quadruple (RFQ) section to the entrance of HEBT section with the goal of minimizing any possible beam losses. We used TraceWin code developed by CEA Saclay for linear and non-linear, 2D or 3D, charged particle beam dynamics calculations and optimization of beam parameters. Based on the performed calculations and optimizations we recommended implementing a commissioning line with solenoids as leading elements.

Observation of 99Mo radioactivity produced in natural molybdenum irradiated with an electron beam from a linear industrial accelerator

Tue, 21 Oct 2025 00:00:00 GMT

The authors present the first observation of the production of 99Mo using a direct electron beam obtained from an electron linear accelerator in the 10–20 MeV energy region. Three disks of natural molybdenum, with diameters of 20 mm and thicknesses of 0.12 mm, 0.33 mm, and 1.13 mm, respectively, were irradiated by an electron beam with the most probable energies of 12.6 MeV and 15.6 MeV. The highest observed activity in the experiment was equal to 646 ± 30 kBq, which is in good agreement with Geant4 simulations. Although 99Mo production is significantly higher with gamma beams, the presented results contribute to the analysis of an interesting electrodisintegration process.

Dose enhancement effects of different-sized nanoparticles on tumors and surrounding tissues using Geant4 track structure simulation

Fri, 22 Aug 2025 00:00:00 GMT

Free radicals, which are the most important contributors to cell death in radiotherapy, appear to increase in the presence of nanoparticles. The nanoparticles can be localized within tumor tissues, providing enhanced protection to normal tissues during radiation therapy while achieving significant dose enhancement within tumors. In our study, the dose effects of different sizes of spherical gold nanoparticles were analyzed in the tumor environment and surrounding tissues under photon radiation at various energies with the track structure code using the TOPAS interface. The nano-lattice method was used to create an environment similar to the diffusion-based distribution of nanoparticles in the medium. The Geant4-DNA code was utilized for simulations conducted in this study. Although the interaction cross-section is lower at MeV photon energy levels, the results still indicate an increase in dose due to the presence of nanoparticles (NPs) in the medium. As the size of gold nanoparticles increases, the spread in dose enhancements becomes more apparent. The lowest average dose enhancement factor (DEF) values at lateral points were observed for 28.4 nm NPs at MeV photon energy. In this study, the contribution of gold nanoparticles to dose enhancement was investigated using the Monte Carlo track structure algorithm. Additionally, the potential dose variations in the surrounding tissue resulting from the introduction of gold nanoparticles were analyzed. Even though an increase in DEF values was observed at MeV energy levels, these values might vary with a better understanding of biological effects such as cell cycle disruption, oxidative stress, and impaired DNA repair. This study offers valuable insights into nanoparticle-assisted radiation applications, including optimal nanoparticle size and applicable energy levels. By enhancing our understanding of the effects on tissues beyond the tumor and within the surrounding environment, it aims to provide critical information for researchers in the field and make a meaningful contribution to the literature.

Beyond a million years: Robust radiation shielding for high-level waste

Fri, 22 Aug 2025 00:00:00 GMT

A recent paper focused on gamma dose rates from unshielded high-level waste over periods exceeding 1 million years and demonstrated that this waste remains hazardous essentially indefinitely. This paper presents a novel perspective by focusing on the practical requirement of shielding to protect from this hazard. Using concrete as the reference material, this paper shows that the required thicknesses stabilize to several tens of centimeters at 1 million years and must remain robust for each individual spent fuel (SF) and vitrified high-level waste (VHLW) form essentially indefinitely, including relevant fragments. These new results provide an additional perspective on an enduring hazard that has been overlooked in discussions of the choice of fuel cycle and in the design and safety analysis of geological repositories. Further research and data needs are identified.

A review of emerging trends in experimental, simulation, and theoretical methods for dose calculation in radiation processing

Fri, 22 Aug 2025 00:00:00 GMT

Dosimetry serves as the backbone of ionizing radiation treatment in radiation processing, ensuring precision and accuracy in transferring the absorbed dose for medical sterilization and phytosanitary applications. Over the years, methods for calculating and measuring the absorbed dose have significantly advanced. Although experimental dosimetry remains indispensable, simulation techniques – such as Monte Carlo (MC) methods – have gained prominence by providing deeper insights into the physical processes of radiation interactions. Additionally, theoretical methods continue to provide accurate dose calculations, contributing to the field’s progress. This study examines recent advancements in dose calculation techniques for radiation processing, highlighting individual methods – experimental, simulation-based, and theoretical – as well as their combinations to achieve accurate and reproducible dose measurements. It also addresses the challenges associated with each radiation processing method and discusses future prospects for improving the dosimetry of radiation processing techniques.

Humanity's uranium-238 inventory: A significant and enduring gamma-radiation liability

Fri, 02 May 2025 00:00:00 GMT

Uranium-238 (U-238), accounting for 99.3% of naturally occurring uranium, primarily utilized for nuclear energy production, is also used in civilian and military applications, leading to vast, geographically dispersed stocks across different byproduct streams. While traditional risk assessments focus on chemical toxicity and alpha radiation, the gamma risks from the U-238 decay chain remain overlooked. Using dose-progression modeling and secular equilibrium analysis, this work quantifies the timeline and magnitude of U-238-induced gamma hazards from depleted uranium (DU), spent fuel (SF), and mill tailings. Findings show that gamma emissions from U-238 inventories exceed radiological safety thresholds well before secular equilibrium, necessitating revised risk assessments and improved, durable containment strategies. By highlighting this underexplored health and environmental issue in nuclear science, the study emphasizes the persistent challenge of managing Humanity's U-238 inventory, which represents a significant and enduring gamma liability across all timescales. Notably, only about 8% of this inventory is managed under robust long-term plans, while the remaining 92%, comprising DU and U-238 in mill tailings, remains inadequately prepared for the future. Addressing the gamma hazards of U-238's decay chain requires a paradigm shift in how this radionuclide is managed. Key priorities for action are identified.

Deuterium isotope effects in mechanistic studies of biotransformations of l-tyrosine and p-hydroxyphenylpyruvic acid catalyzed by the enzyme l-phenylalanine dehydrogenase

Fri, 02 May 2025 00:00:00 GMT

The mechanisms of the reversible oxidative deamination of l-tyrosine to p-hydroxyphenylpyruvic acid and reductive amination of phenylpyruvic acid to l-phenylalanine, both catalyzed by the enzyme l-phenylalanine dehydrogenase (PheDH, EC 1.4.1.20), were investigated using the kinetic isotope effect (KIE) and solvent isotope effect (SIE) methods. The values of deuterium kinetic effects in the 2-position of l-tyrosine and KIE in the (3S)-position of phenylpyruvic acid and solvent isotope effects for both reactions were determined using the non-competitive spectrophotometric method. Some mechanistic details of these biotransformations were discussed.

Effects of irradiating the beam dump with the main electron beam of the superconducting linear accelerator PolFEL

Fri, 02 May 2025 00:00:00 GMT

The transport of both primary and secondary radiation in the beam dump was conducted using Monte Carlo analysis. The radiation leakage level through the shielding walls of the bunker of the superconducting, linear electron accelerator PolFEL during beam operation, as well as the radiation dose generated by radioactivity, and the activity level of the beam dump and soil after beam operation were examined. The analysis encompassed three main electron beams with energies of 72 MeV, 187 MeV, and 280 MeV, corresponding to the need to deposit in the beam dump 900.0 W, 935.1 W, and 1400.1 W of electron beam power, respectively. It was determined that 99.86%, 99.83%, and 99.81% of the primary electron beam power was deposited in the designed beam dump. It was determined that the radiation leakage level through the lateral walls of the bunker, outside which nonexposed workers may stay, should be <1.8 · 10−4 μSv/h, 0.008(5) μSv/h, and 0.10(2) μSv/h, respectively. It was calculated that the radiation dose rate generated by radioactivity allows staying on the shielding plates above the beam dump no earlier than about a day after the end of the 30 days exposure period of the beam dump. The maximum activity level for the soil activity level at the most exposed location should be <0.008 Bq, 3.37(15) Bq, and 29.8(9) Bq for indicated above electron beam energies, respectively.

Monte-Carlo simulations of a neutron source based on a linear electron accelerator

Tue, 18 Feb 2025 00:00:00 GMT

Neutron beams are employed in a multitude of applications, including neutron activation analysis, neutron radiography and tomography, nuclear waste assays, reactor start-up sources, studies of material response, geological analysis, calibration standards and cancer therapy. The global demand for access to neutron beams is increasing, necessitating the development of relatively simple, efficient and easy-to-use neutron sources to address the more complex challenges of scientific research and industrial application. One relatively readily available method is to use a linear electron accelerator to produce beams of fast neutrons. The neutron generator, comprising of an electron linear accelerator and a tungsten X-ray converter, is capable of producing a maximum neutron flux of 1.53·1010 n/s to 1.45·1013 n/s at electron energies of 10–50 MeV, with an average electron beam current of 120 μA, corresponding to an intensity of 7.5·1014 e/s. The results of the neutron generator modelling conducted with the FLUKA Monte-Carlo code are presented in this article for an equivalent incident beam power of 1.2–6.0 kW. The optimal tungsten converter thickness is proposed as a means of achieving the maximum neutron flux in all directions.

Toward precision dosimetry: Harnessing the versatility of radiochromic films in radiation measurements

Tue, 18 Feb 2025 00:00:00 GMT

This paper presents the findings of a study on dose rate distribution in air and water phantoms, recorded using Gafchromic films. Low energy accelerator with X-ray tube (NALR), a system developed at the National Centre for Nuclear Research (NCBJ), generated by the dose rates. The primary objective of this research was to employ the X-ray tube as a source of X-ray radiation and assess dosimetry techniques using radiochromic films for radiological protection purposes. Gafchromic MD-55-V2 and EBT films were utilized for measurements. Two-dimensional measurements with Gafchromic dosimetry films were compared against ionization chambers AP 2.0 (in water) and PTW-23342 (in air) to validate radiation dose rate distributions. Furthermore, the film response over different days post-exposure highlights the importance of scanning radiochromic films on the first day after exposure.

Spectroscopic techniques in the investigation of extraordinary medieval Polish coins: Revealing the presence of hidden cores

Tue, 18 Feb 2025 00:00:00 GMT

Cross denars, frequently found in Polish hoards, were traditionally thought to be Ag coins with some Cu content. This study investigates the possibility of a hidden Cu core beneath the Ag or Ag–Cu surface of these coins. It raises questions about whether they were counterfeits or intentionally designed for mass production. Unlike Roman denarii, which revealed their cores when broken, the examination of cross denars without damage is challenging. Optical microscopy and microanalysis revealed differences in the composition of early medieval Polish coins, challenging the belief that cross denars were homogeneous Ag–Cu alloys. Detailed spectroscopic analyses, including energy-dispersive X-ray fluorescence (ED-XRF), scanning electron microscopy with energy-dispersive X-ray spectroscopy (SEM-EDS), micro X-ray fluorescence (μXRF), and microparticle-induced X-ray emission (μ-PIXE) measurements, were conducted. These analyses of two cross denars uncovered one composed of an Ag–Cu alloy and another manufactured by plating a Cu–Zn core with an Ag sheet. This suggests the need for further research in the history and technology of minting in Poland in the Early Middle Ages. It also prompts a reconsideration of the applicability of noninvasive X-ray techniques for archaeological examinations.

Application of improved matrix dilution method in quantitative analysis of Ni-Co-Mn ternary precursor

Wed, 20 Nov 2024 00:00:00 GMT

When using energy-dispersive X-ray fluorescence (EDXRF) to analyze Ni-Co-Mn (NCM) samples, if the standard sample's concentration greatly differs from the unknown sample's concentration, the traditional matrix dilution method requires repeated dilution and measurement. This makes the process time-consuming and labor-intensive. This study proposes an improved matrix dilution method to reduce sample preparation and analysis. This method first establishes a functional relationship model between the dilution factor and the characteristic X-ray intensity. Then the characteristic X-ray intensity of the analyzed element can be calculated by this model, avoiding unnecessary dilution and measurement steps. To verify the effectiveness of this method, the dilution factors and characteristic X-ray intensities of the test samples were fitted using the established functional relationship. The fitting results showed that the fitting coefficients of determination of the Mn, Co, and Ni were all 0.999. Quantitative analysis was performed on the characteristic X-ray intensity fitting values and measured values of the test samples. The results showed that the quantitative results of the two were consistent. The average error of the three elements for both methods was 1.1% and 0.7%, respectively. It shows that through the established functional relationship, the characteristic X-ray intensity can be effectively calculated by the dilution factor. This method can be applied to samples with identical elements and proportions of target elements, but with different concentrations, using the same set of standard samples.

New chamber stapes prosthesis: Effect of ionizing radiation on material and functional properties

Wed, 20 Nov 2024 00:00:00 GMT

New chamber stapes prosthesis (ChSP) is a middle-ear prosthesis intended for use in ear surgery for restoring the patient's middle ear function. As the prosthesis is an implantable medical device, it must be sterilized before use. However, possible alterations in the material and the functional properties following the sterilization process can influence the safety aspects while using the prosthesis. The purpose of this paper was to determine the effects of ionizing radiation (IR) on the physicochemical and biological properties of the new chamber prosthesis by utilizing EPR spectroscopy, mechanical testing, and cytotoxicity studies. Our research shows that the radiation treatment increases the hardness and the elastic modulus of the polymer, decreases the stiffness of the prosthesis membrane, and does not cause chemical changes in the polymers that may result in cytotoxicity. Furthermore, new ChSPs were successfully tested in preclinical in vitro tests. The test results justify the undertaking of further work, including in vivo biocompatibility tests and clinical trials, which would eventually lead to the increased use of the prosthesis in clinical practice.

Hall probe calibration in high-precision magnetic field mapping system of superconducting cyclotron

Wed, 20 Nov 2024 00:00:00 GMT

IntroductionSuperconducting cyclotron can generate high-energy proton beams and are mainly used for radiation therapy of tumors and cancers. In the superconducting cyclotron SC200, the maximum magnetic induction intensity can typically reach up to 4.6 T, and the magnetic field accuracy is 1e-4. Hall probes are commonly used tools for measuring high-intensity magnetic fields. ObjectiveThrough comprehensive consideration, this study selects the SENIS Low-Noise Teslameter 3MH5 and Hall probe C to measure the magnetic field. When the magnetic field exceeds the range of 2 T, the measurement accuracy of the Hall probe is less than 1e-4, and the Hall probe needs to be calibrated to improve its measurement accuracy. MethodsThe Hall probes are calibrated using Swiss METROLAB PT2025 nuclear magnetic resonance (NMR) Tesla instrument and 1062 probe. Based on the calibration principle, a calibration system platform was built, test data were collected, and calibration curves were obtained. At the same time, the calibration data were analyzed through cross-validation experiments using the cubic polynomial fitting method. ResultsThe results indicate that the test deviation range is from −0.1 g to 0.1 g, and the measurement accuracy can reach 1e-4. ConclusionIn summary, the Hall probe can accurately measure the magnetic field distribution of the superconducting cyclotron. It can provide accurate and important data for the calculation and analysis of particle beam dynamics.

Beyond one million years: The intrinsic radiation hazard of high-level nuclear wastes

Wed, 20 Nov 2024 00:00:00 GMT

This paper highlights the absence of quantitative estimates regarding the intrinsic radiation hazard of high-level nuclear wastes, namely, spent fuel (SF) and vitrified high-level wastes (VHLW), for periods exceeding one million years. Using available data, conducting scoping calculations of radiation doses, and comparing the results to radiation protection guidelines and natural background radiation, this paper shows that high-level wastes cannot be safely handled or left unprotected essentially indefinitely. By quantitatively evaluating the dose rates of unshielded SF and VHLW, this study identifies critical new insights, such as the roles of the Np-237 decay chain; the eventual, long-term dominance of the U-238 decay chain; and the interplay of three actinide decay chains, including the significant role of Bi-214. These findings fill a gap in the literature and emphasize the need for more detailed investigations in this as-yet-unexplored research area, which has a direct bearing on technical and societal decision-making for both waste disposal safety and the choice of the back end of the nuclear fuel cycle.