Abstract The study of natural radionuclides, which have been present in our lives since the formation of the world, is very important in our daily lives because of their effects on public health. There are currently more than 60 known radionuclides, but among these, the most important are uranium, thorium and potassium, which are considered the primary sources for the production of gamma radiation. In this study, the natural radionuclide activity concentrations of soil samples collected from 15 different locations in the Aegean region of Turkey to assess radiological hazards were determined using an HPGe detector based on a high-resolution gamma spectrometry system. The measured soils were also analysed for radiological parameters, which were evaluated by comparison with the literature.
Abstract Gamma radiation aging degradation of natural rubber and its blends: Role of sulphur-based curing agent. Gamma irradiation is a suitable method for the enhancement of elastomeric breakdown products through radiation crosslinking, which can improve the mechanical properties and service performance. In the present work, hybrid-filled natural rubber (NR)/styrene butadiene rubber (SBR) (50/50) composites containing a constant carbon black loading of 50 parts per hundred (phr) and different amounts of precipitated silica (Hisil, 0–20 phr) were prepared and exposed to gamma rays with absorbed doses of 0, 100, 150 and 200 kGy. The influence of silica loading and gamma irradiation on compression set and elastic recovery of the composites was also assessed in a consecutive manner. The results indicated that with the increase of the Hisil concentration, the elastic recovery was improved and compression set was reduced stepwise due to the reinforcing mechanism of silica as well as stronger filler–rubber interaction, which induced the formation of a more stable and rigid network structure. The performance of the composites was further improved by gamma irradiation as the increased crosslink density led to reduced permanent deformation and enhanced elastic recovery. The unique synergy between higher Hisil loading and gamma irradiation resulted in the best compromise of filler reinforcement and radiation-induced crosslinking among components, and gave the undoubted best mechanical stability and long-term durability. These results indicate that tuning both silica concentration and gamma irradiation dose is a promising, but more generic, approach to tailor the structure and properties of NR/SBR composites for advanced sealing and engineering uses.
Abstract Mesoporous Mn 3 O 4 was developed as an efficient single-step sorbent for the selective separation of Ag + from Pd 2+ , enabling a practical approach for the production of carrier-free 111 Ag. The material was synthesized via a CTAB-assisted co-precipitation method and characterized using FTIR, XRD, XPS, and EDX techniques. Its performance was evaluated in both batch and column systems. The sorbent, with an average pore size of about 4 nm and a surface area of 24.87 m 2 g −1 , exhibited high adsorption capacities for Ag + of 132 ± 6.6 mg g −1 (batch) and 112 ± 5.5 mg g −1 (column) at pH 3. The separation mechanism is attributed to size-selective mesopore diffusion, facilitated by the smaller hydrated radius of Ag + compared to Pd 2+ , in combination with surface complexation. The material demonstrated excellent chemical stability with negligible manganese leaching. The method was successfully validated for the recovery of 111 Ag from irradiated palladium targets, achieving a yield of 74 % with high radionuclidic purity.
Abstract Naturally occurring radon in groundwater represents a significant public health concern due to exposure through both ingestion and inhalation. This study investigated radon concentrations across 30 groundwater samples collected from northeastern Iraq, together with associated physicochemical parameters and radiological risk assessments. Measured radon concentrations spanned from 2.9 to 29.7 Bq L −1 , with a mean of 12.5 Bq L −1 . Approximately 43.3 % of the sampled sites exceeded the USEPA guideline, whereas all concentrations remained below the WHO and UNSCEAR limits. Radiological health risk indicators, including annual effective dose via ingestion and inhalation pathways and excess lifetime cancer risk, were evaluated across three different age groups. Although the overall total annual effective dose remained beneath the WHO recommended limit of 0.1 mSv y −1 , infants recorded higher dose values than both children and adults, with five sampling locations surpassing this threshold specifically for the infant group. Excess lifetime cancer risk estimates across all age categories fell within USEPA acceptable boundaries. Pearson correlation, skewness, kurtosis, and Shapiro-Wilk statistical tests were applied to examine relationships between radon levels and water quality indicators. Findings highlight the need for targeted mitigation interventions, continuous environmental monitoring, and community awareness initiatives to reduce long-term waterborne radon health risks.
This study evaluated the activity concentrations of naturally occurring radionuclides (232Th, 226Ra, and 40K) and their associated radiological hazard indices, in soils surrounding a rare earth waste residue pile in Northeast China. The mean activity concentrations for 232Th, 226Ra, and 40K were 36.7, 35.2, and 667 Bq kg-1, respectively, all falling strictly within natural background levels. Considering the potential radiological hazards, various hazard indices were calculated, and the results indicated that all indices are within normal limits. Furthermore, statistical analyses were performed on the measured data to comprehensively evaluate the distribution patterns of radionuclides and the interrelationships among radiological parameters.
The present study investigates the optimization of stirring parameters in a solid-liquid mixing system using a full factorial experimental design (23). The effects of stirring speed, particle size, and solid concentration on mixture homogeneity were evaluated using gamma-ray densitometry. The obtained results enabled the development of a statistical model correlating the operating parameters with the system response. The developed model was successfully used to identify the optimal mixing conditions, providing a reliable basis for improving the efficiency and quality of industrial solid-liquid mixing processes.
Abstract This review synthesizes how Life Cycle Assessment (LCA) and Techno-Economic Assessment (TEA) can be jointly used to guide choices for converting diverse nuclear residues into durable final forms suitable for storage and geological disposal across national program contexts. It contrasts established options, including borosilicate glass vitrification for High Level Waste (HLW) and cementation for Intermediate Level Waste (ILW) and Low Level Waste (LLW), with emerging candidates such as Synroc type ceramics, chemically bonded phosphate ceramics, and alkali activated geopolymers. Across these options, the review shows that apparent environmental and cost rankings are often artifacts of modeling choices, especially functional unit selection and the inclusion of repository construction, emplacement, and stewardship within system boundaries. Methodological debates are therefore treated as first order technical issues, not reporting details, covering attributional versus consequential modeling, allocation for by product derived feedstocks, and the representation of long horizon radiological impacts. A central finding is that long-term durability, captured through performance assessment concepts and laboratory leaching metrics, remains the dominant source of epistemic uncertainty, frequently overwhelming material to material differences and propagating into both LCA results and regulatory cost risk in TEA. To improve decision relevance, the review advocates routine probabilistic sensitivity analysis, explicit reporting of boundary cases, and integrated workflows that couple process engineering inventories with near field geochemistry scenarios and finance modules. Finally, it positions multi criteria decision analysis as a practical bridge for stakeholders to examine trade offs among volume reduction, energy demand, maturity, and qualification burden under transparent value weightings.
Abstract New types of borate glass doped with BaO, PbO 2 , and Y 2 O 3 were developed for radiation shielding. The attenuation properties of these glasses were calculated theoretically using the Phy-X software and measured experimentally with an HPGe detector and various radioactive sources. At 0.059 MeV, the theoretical results showed a high linear attenuation coefficient (LAC) (range: 13.66–17.98 cm −1 ) that decreased with increasing energy, resulting in a minimum value range of 0.20–0.23 cm −1 at 1.332 MeV. The LAC was strongly influenced by the chemical composition of the glasses, with the results demonstrating higher LACs with greater PbO 2 , BaO, and Y 2 O 3 content incorporated into the glasses. The radiation shielding efficiency results suggest that increasing the BaO, PbO 2 , and Y 2 O 3 content raised the radiation attenuation ability of the glasses. It was also found that the half-value thickness elevated with increased radiation energy, thus requiring thicker glass at higher energies.
In this research work, a new series of zinc-borate glasses with the formula (50-x)B2O3-20TeO2-5Bi2O3-(25 + x)ZnO (where x = 0-25 mol%) was fabricated using conventional melt-quenching method, labeled as BTBZ1 to BTBZ6. By analyzing the data of density and the molar volume, it was found that as the amount of ZnO increased from 25 % to 50 % in the BTBZ glasses, the density also increased from 4.02 to 4.87 g cm-3 because the heavier Zn ions contributed to the glass network to form a more compact and densely packed structure. The FTIR spectroscopy results indicated that BO3, BO4, TeO3, TeO4, ZnO4, and Bi-O groups are part of the glass structure, confirming that the bonds are mixed and that the network of glass is highly connected. In addition, the radiation-shielding behavior was tested not only via Phy-X/PSD software, but also using actual gamma-ray sources: Co-60, Cs-137, and Ba-133. For shielding of gamma-radiations, following parameters were determined: mass attenuation coefficient, linear attenuation coefficient, half-value layer, tenth-value layer, and mean free path. The research showed that raising the amount of ZnO enhanced the glasses' gamma-ray attenuation, suggesting that these glasses can be the suitable candidates as transparent shields in medicine, nuclear, and aerospace applications.
Abstract Excitation functions of the reactions 85 Rb( p,n ) 85m Sr, 85 Rb( p,n ) 85m,g Sr and 87 Rb( p,n ) 87m Sr were measured using the activation technique in the proton energy range of 2–5 MeV with a low-energy Tandem Accelerator. Our new data sets, combined with those of Kastleiner et al. data obtained previously at FZJ using enriched target 85 Rb, provide complete excitation functions of the 85 Rb( p,n ) 85m Sr and 85 Rb( p,n ) 85m,g Sr reactions. The experimental data were reproduced well by a model calculation using the code TALYS-2.0 after selection of a few input parameters, confirming the reliability of the experimental data. In contrast, model calculations based on global parameters in the data library TENDL-2023 overestimated the cross sections by nearly a factor of two compared to TALYS-2.0. The isomeric cross-section ratio 85m Sr/ 85g Sr was experimentally determined from the measured activities at the end of bombardment (EOB) up to 5 MeV. Above 5 MeV, the isomer ratio was also derived from the cross sections reported by Kastleiner et al., extending the information upto 15 MeV. The trend was interpreted in terms of the reaction energy available and the effect of spin distribution of the level density. Finally, the 85 Rb( p,n ) 85 Sr reaction is demonstrated to be a promising route for the production of radionuclidically pure 85 Sr at a small cyclotron, possibly for medical applications.
In the 4.93, 6.61, 8.31 and 10.92 MeV spectrum averaged neutron-induced fission of 232 Th, independent isomeric yield ratios (IR) of the fission products 131m,g Te and 133m,g Te have been experimentally determine. An off-line gamma-ray spectrometric technique was used for the measurement. The average neutron energies used were obtained from the 7 Li(p, n) reaction by using the proton energies of 7, 11, 15 and 18.8 MeV. From the IR values, the root mean square fragment angular momenta ( J RMS ) were deduced by applying spin dependent statistical model analysis. The effect of nuclear structure and role of excitation energy on the IR and J RMS values of 131m,g Te and 133m,g Te were examined.
Electrochemical sensing has emerged as a powerful analytical approach for the ultra trace determination and speciation of radionuclides across environmental systems and nuclear fuel cycle process streams. This review synthesizes recent advances in electrode engineering, surface modification strategies, and redox mechanistic understanding that have collectively transformed electroanalytical radiochemistry. Fundamental techniques such as adsorptive stripping voltammetry and ion selective potentiometry are discussed in the context of their ability to deliver picomolar level detection while providing direct electronic signatures of oxidation states, a capability not readily achievable with spectrometric methods. Progress in replacing mercury based systems with environmentally benign solid state platforms, including bismuth film, boron doped diamond, screen printed electrodes, and nanomaterial modified carbon architectures, has significantly enhanced sensitivity, stability, and field deployability. Equally important are advances in selective interfaces such as ion imprinted polymers, molecularly imprinted polymers, metal organic frameworks, and Prussian Blue analogues, which mitigate matrix interferences in seawater, groundwater, biological samples, and high level liquid waste. This review comprehensively examines the electrochemical behaviors of uranium, plutonium, neptunium, americium, technetium, strontium, and cesium, highlighting the interplay between electrode materials, complexation chemistry, radiation induced perturbations, and kinetic limitations. In addition, operational considerations including memory effects, waste minimization, radiation damage, and comparative performance with inductively coupled plasma mass spectrometry are critically evaluated. Collectively, these developments demonstrate that modern electrochemical sensors offer a versatile, low cost, and highly informative complement to traditional radiometric and mass spectrometric techniques, particularly for applications requiring rapid on site screening and oxidation state resolved monitoring in complex nuclear environments.
Various types of ceramic waste fragments were examined to study their gamma-ray attenuation properties and determine their suitability as an environmentally friendly and economical radiation shielding material. The microstructure of the ceramics was analyzed using scanning electron microscopy (SEM). Energy-dispersive X-ray spectroscopy (EDX) was used to determine the chemical composition of the samples. Experiments were performed to measure the linear attenuation coefficient (LAC), half-value layer (HVL), tenth-value layer (TVL), and mean free path (MFP) for photon energies of 241Am (59.5 keV), 137Cs (662 keV), 60Co (1173 and 1332 keV). Theoretical calculations were performed using XCOM software to validate the experimental results and ensure accuracy. The results showed excellent agreement between the experimental and theoretical attenuation values (<= 6 %), confirming the reliability of both methods. Furthermore, at all tested energies, the Emirates ceramics coded as S3 exhibited the highest LAC value (0.924 cm-1) at 59.5 keV and (0.179 cm-1) at 1332 keV, making it more effective at attenuating gamma rays than the other tested ceramic samples. The superior gamma-shielding properties of S3 are attributed to its optimized structure, which enhances its overall density and the presence of high-atomic-number elements (silicon, iron, and calcium). These results support the potential use of ceramic breakage waste in future radiation shielding applications.
Based on comprehensive mineralogical characterization and chemical composition analysis, systematic column leaching tests were conducted to evaluate uranium extraction performance. The optimized conditions - including a particle size of -10 mm, an initial sulfuric acid concentration of 30 g L-1 during acidification, an irrigation intensity of 20 L m-2 h-1, and a leachate pH maintained within 1.8-2.0 - yielded a maximum uranium leaching efficiency of 89.67 %. A kinetic model derived from the Bernoulli equation was developed to describe leaching behavior under varying particle sizes and irrigation rates, demonstrating excellent agreement with experimental data. This validated model provides robust theoretical support for process optimization and production scheduling in industrial-scale heap leaching operations.
The use of bottled drinking water in the Iraqi Kurdistan has increased significantly due to the general perception that it offers higher quality compared to other water sources. In this study, radon levels in 20 widely available brands of commercial bottled water were measured using RAD7 alpha detector coupled with RAD-H2O system to assess their safety. In addition, physicochemical parameters such as pH, electrical conductivity (EC), and total dissolved solids (TDS) were analyzed. Measured radon radioactivity concentrations ranged from 20.9 +/- 2.7 to 46.7 +/- 6.1 mBq L-1, with a mean value of 33.8 +/- 1.65 mBq L-1, well below the USEPA and WHO. To assess potential radiation health risks, the total annual effective dose and excess lifetime cancer risk were calculated for the three age groups based on the rate of consumption of conventional bottled water. Estimated risk indices encompassing inhalation, ingestion, total effective dose, and excess cancer risk over a lifetime were found to be below internationally accepted reference levels, indicating that associated radiation risks are low. In addition, a statistical analysis was performed to examine the distribution and relationships among radon levels and physicochemical parameters. This analysis included assessment of skewness, kurtosis, and Pearson coefficients to better understand the underlying characteristics of the data and possible relationships. The measured radon activity concentrations and associated radiological dose estimates indicate negligible health hazards from routine consumption of commercially available bottled drinking water in Iraqi Kurdistan, with the findings serving as a regional baseline for future radiological water quality assessments.
This study explores a sustainable approach to gamma radiation shielding and waste recycling by developing epoxy-based composite materials reinforced with varying percentages (0-50 %) of cathode ray tube (CRT) glass. The primary objective is to assess the mechanical, microstructural, thermal, and radiation attenuation properties of these eco-friendly composites. Experimental linear attenuation coefficients (LAC) values were validated using theoretical calculations, showing good agreement. Key shielding parameters, including half-value layer (HVL) and radiation attenuation ratio (RAR%), were calculated. The ER-CRT-50 sample, with the highest CRT glass content, exhibited the best shielding performance, achieving an LAC of 1.464 cm(-1) at 0.059 MeV, significantly higher than ER-CRT-0's 0.273 cm(-1), and an RAR of 99.93 % at 5 cm thickness. Microstructural analysis revealed that ER-CRT-30 displayed optimal filler-matrix adhesion and enhanced fracture toughness, while ER-CRT-50 showed agglomeration-related defects. Thermogravimetric analysis and differential scanning calorimetry confirmed improved thermal stability with CRT addition, with ER-CRT-30 retaining 18.5 % residual mass at 450 degrees C compared to ER-CRT-0's <10 %. Mechanical testing demonstrated that ER-CRT-30 achieved the highest strength, with a maximum stress of 6.5 MPa at 5.5 % strain, compared to ER-CRT-0's 3.0 MPa at 0.65 % strain. These results indicate that epoxy composites reinforced with 30 wt.% CRT offer an optimal balance of gamma radiation shielding, thermal stability, and mechanical performance, presenting a viable and eco-friendly solution for radiation shielding applications.
Composite PVA-PVP films doped with varying concentrations of CoCl2 were fabricated using the casting technique to develop a low-cost, effective routine dosimeter used in estimating doses in industrial sterilization and food preservation. Although polymeric film dosimeters are widely used, many suffer from moisture sensitivity, which affects their stability and measurement reliability. The influence of ambient humidity and the effectiveness of mitigation strategies remain insufficiently addressed. The prepared films were irradiated using a Cobalt-60 source up to 70 kGy. Structural and optical properties were characterized by FTIR, XRD, TEM, and UV-visible spectroscopy. XRD analysis revealed reduced crystallinity, accompanied by good miscibility of CoCl2 within the PVA/PVP matrix, as supported by FTIR band variations. UV-VIS spectra showed characteristic absorption bands at 517 and 670 nm, while the optical energy gap decreased from 4.91 to 4.13 eV with increasing CoCl2 content. Upon irradiation, the films exhibited a progressive color change from pale to deep blue, with dose response dependent on CoCl2 content. A detailed humidity study demonstrated that ambient moisture has a significant impact on film stability, whereas storage in silica gel effectively preserves its dosimetric performance. Films stored under controlled dry conditions showed superior stability, estimated by 3 %, 6 % pre irradiation and 4 %, 6 % after irradiation in dark and light, respectively. Additionally, in humid environments, the films displayed a distinct blue-to-red color transition, indicating potential application as visual humidity indicator labels. The combined uncertainty (2 sigma) was 4.68 %, suggesting suitability for routine moderate-dose industrial dosimetry.
Uranium and plutonium isotopes were determined in water and sediment samples from the main dams that feeds the Cutzamala system, Villa Victoria and Valle de Bravo in the State of Mexico, Mexico. Actinides were extract and purify from the samples using chemical and radiochemical techniques, deposited in fine sources and measured by alpha spectrometry. Uranium isotopes in the water and sediment samples were found within the levels of natural uranium. The presence of plutonium isotopes were also detected at very low level and, in some cases, they were undetectable. The uranium activity concentration for water and sediment samples varied from 0.48 to 7.00 mBq/L and from 68 to 1,523 mBq/kg, respectively. The estimated levels for Pu239+240 in water and sediment samples were found between 0.12 and 0.4 mBq/L and between 1.2 and 17 mBq/kg, respectively. Furthermore, the U-234/U-238 isotopic ratios revealed important differences between the studied dams. The samples collected from Valle de Bravo dam exhibit a U-234/U-238 isotopic ratios >1. In contrast, samples from Villa Victoria dam present ratios <1. These differences could be associated to the type of discharges, e.g. due to the use of phosphate fertilizers, the rock leaching, among others. The levels of uranium and plutonium isotopes in the water and sediments samples analyzed are very low, and no health effects are expected.
New epoxy based ceramic materials filled with various nano-sized (average size of 30 nm) heavy metal oxides (HMO) such as ZnO, CuO, WO3, and CeO2 have been investigated. The shielding performance of the epoxy composites was tested experimentally utilizing source-collimator-detector technique. The gamma sources emit different lines 0.059 MeV from Am-241, 0.662 MeV from Cs-137 and (1.173, 1.333 MeV) from Co-60. The density was measured experimentally and achieved the highest value of 1.395 g/cm(3) for both E-WO3 and E-CeO2, while the lowest value was for E-ZnO at 1.376 g/cm(3). The linear attenuation coefficient (LAC) was calculated by Phy-X software and compared with the experimental data. The LAC was 0.748, 0.702, 1.315 and 3.044 cm(-1) for E-ZnO, E-CuO, E-WO3 and E-CeO2, respectively at 0.059 MeV, while at 1.333 MeV, the LAC was 0.079, 0.079, 0.081 and 0.080 cm(-1), respectively. The fast neutron removal cross-section (FNRC) was 0.0997, 0.1005, 0.0991 and 0.0993 cm(-1), respectively, which gives better performance in probability of absorbing fast neutrons than ordinary concrete.
Breast cancer remains the most prevalent malignancy among women worldwide, with HER2 overexpression occurring in 20-30% of cases and representing an aggressive disease phenotype. This study aimed to develop a novel theranostic radiopharmaceutical kit for breast cancer treatment by radiolabeling trastuzumab (TRZ) with lutetium-177 (Lu-177). TRZ was conjugated with four chelating agents (EDTA, DOTA, DTPA, and MAG3) at 1:1, 1:10, and 1:100 nmol ratios and formulated as both solution (S1-S12) and lyophilized kit (L1-L12) preparations. Physicochemical characterization confirmed homogeneous particle distributions (PDI <= 0.38), isotonic osmolality (309-325 mOsmol/kg), and TRZ content consistent with theoretical values (893-990 & micro;g). Radiolabeling conditions were systematically optimized across pH (5, 7, and 9), incubation time (15-60 min), and radioactivity levels (5-50 mCi), with quality control performed by dose calibrator and RP-HPLC. Cytotoxicity assessment via WST-1 assay demonstrated selective toxicity toward MCF-7 breast cancer cells (83-85% viability at 72 h) while preserving healthy CRL-10762 cells (>95% viability), supporting the therapeutic selectivity of the developed formulations. MAG3-based formulations (S11, L11) demonstrated optimal radiolabeling performance, achieving >98% efficiency at pH 7.0 with 60-minute incubation and maintaining >95% radiochemical purity for seven days at 50 mCi. In vivo SPECT/CT imaging and quantitative biodistribution studies in MCF-7 tumor-bearing Balb-C nude mice confirmed superior tumor retention for Lu-177-L11, with peak accumulation of 15.2 +/- 1.8 %ID/g at 72-96 hours - representing a 5.1-fold increase over free Lu-177 - and an ROI value of 583.67 +/- 18.77, significantly outperforming literature-reported DOTA-based conjugates. These findings support the clinical translation potential of the Lu-177-MAG3-TRZ lyophilized kit as a promising theranostic agent for HER2-positive breast cancer.
