Applied Radiation and Isotopes最新文献

{"title":"Characterization of a high activity industrial 60Co irradiator for controlled low dose applications at Da Nang irradiation facility","authors":"Hoang Thanh-Phi Hung,&nbsp;Cao Van Chung","doi":"10.1016/j.apradiso.2025.112333","DOIUrl":"10.1016/j.apradiso.2025.112333","url":null,"abstract":"<div><div>High-activity ⁶⁰Co irradiators can be adapted for low-dose research without hardware modification. We characterized the Da Nang Irradiation Facility (VINAGA1; 151 kCi ≈ 5.6 PBq) using MCNP6.3 and validated predictions with calibrated Fricke dosimetry across 20–200 Gy. A quasi-uniform plane was established at z = 80 cm above the conveyor base, with a dose-uniformity ratio (DUR) of 1.20–1.46. For most positions, the mean absolute deviation between simulation and measurement was &lt;10 %; one boundary location exhibited 25.7 % due to steep local gradients and millimeter-scale placement sensitivity. Doses used two-sided exposures totaling 7.5–48 min per side, scaled to dose. Within the 60–120 Gy validation window, the mean absolute deviation was 8 % with a −4.9 % bias versus prescription. These results show that a Category-IV panoramic irradiator provides uniform low-dose fields suitable for mutation breeding, phytosanitary treatments, and materials research, offering a practical, cost-effective path to repurpose industrial ⁶⁰Co facilities for controlled low-dose Research and Development (R&amp;D), validated for accuracy and reproducibility, with transparent limits and scope.</div></div>","PeriodicalId":8096,"journal":{"name":"Applied Radiation and Isotopes","volume":"229 ","pages":"Article 112333"},"PeriodicalIF":1.8,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145659968","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Mineralogical controls on natural radioactivity in the mineralized gneiss of Khor Abaleia, Southeastern Desert, Egypt","authors":"Gehad M. Saleh,&nbsp;Nareman M. Harpy,&nbsp;Mohamed S. Kamar,&nbsp;Waleed S. Ibrahim,&nbsp;Mai M. Fathy,&nbsp;Mona M. Fawzy","doi":"10.1016/j.apradiso.2025.112336","DOIUrl":"10.1016/j.apradiso.2025.112336","url":null,"abstract":"<div><div>This study examines the mineralogical and radiological characteristics of mineralized gneiss from the Khor Abaleia and Wadi Nugrus areas in Egypt's Southeastern Desert, with particular emphasis on the mineralogical controls governing natural radioactivity. A total of eighteen representative samples were collected: twelve from two distinct units of the Abalea gneiss (AB1 and AB2) and six from the Nugrus gneiss. Heavy liquid separation, X-ray diffraction (XRD), and scanning electron microscopy with energy-dispersive spectroscopy (SEM-EDS) were employed to characterize heavy minerals and associated radioactive phases. The AB1 gneiss displayed the highest content of total heavy minerals (4.63 wt%), followed by AB2 (2.78 wt%) and Nugrus gneiss (1.85 wt%). Identified radioactive minerals include kasolite, uranophane, thorite, and uranothorite, together with zircon, xenotime, and ferrocolumbite, confirming the polymetallic and radioactive nature of these lithologies.</div><div>Geochemical and radiometric data reveal marked variations in uranium, thorium, and potassium contents, as well as in disequilibrium states. AB1 samples are enriched in uranium (avg. 346 ppm; up to 4625 Bq/kg) with significant uranium–radium disequilibrium (avg. eU/Ra(eU) = 2.4). AB2 samples, although uranium-bearing (avg. 305 ppm; up to 4588 Bq/kg), exhibit elevated thorium levels (avg. 1588 Bq/kg), extremely low potassium, and low disequilibrium ratios (avg. 0.65), suggest extensive uranium leaching. Nugrus gneiss samples are comparatively less enriched in uranium (avg. 143 ppm; 1680 Bq/kg) but retain moderate thorium and higher potassium contents.</div><div>All samples investigated exceed international radiological safety thresholds. AB2 is the most hazardous (Ra_eq avg. 6519 Bq/kg; AED_in 26.7 mSv/year; ELCR 1.23 %), followed by AB1 and Nugrus gneiss. These results demonstrate that mineralogical composition exerts primary control on radionuclide distribution, disequilibrium patterns, and subsequent radiological risk. The findings highlight both the geochemical mechanisms responsible for radionuclide mobilization and the significant health and environmental hazards associated with these rocks. This underscores the necessity for continuous monitoring and risk mitigation strategies in any prospective mining or exposure scenarios.</div></div>","PeriodicalId":8096,"journal":{"name":"Applied Radiation and Isotopes","volume":"229 ","pages":"Article 112336"},"PeriodicalIF":1.8,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145617594","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Nuclear excitation functions for medical isotope production: Targeted radionuclide therapy via natIr(d,x)193mPt","authors":"H.L.O. Ekeberg ,&nbsp;A.S. Voyles ,&nbsp;M.S. Basunia ,&nbsp;J.C. Batchelder ,&nbsp;L.A. Bernstein ,&nbsp;D.L. Bleuel ,&nbsp;K.C.W. Li ,&nbsp;E.M. Martinsen ,&nbsp;E.F. Matthews ,&nbsp;J.T. Morrell ,&nbsp;N.I.J. Pettersen ,&nbsp;S. Siem","doi":"10.1016/j.apradiso.2025.112311","DOIUrl":"10.1016/j.apradiso.2025.112311","url":null,"abstract":"<div><div><figure><img></figure> is an Auger emitting radionuclide which may have therapeutic potential, particularly when labeled to the chemotherapeutic drug cisplatin. One challenge to broader explorations of its clinical potential is the need for production routes with high specific activity. As part of a larger campaign to address gaps in reaction data for emerging medical radionuclides, this work seeks to characterize the <figure><img></figure> (d,x) reactions as a potential production pathway for <figure><img></figure> . A stacked target irradiation, consisting of natural iridium, iron, nickel, and copper foils, was performed using a 33 MeV deuteron beam at the Lawrence Berkeley National Laboratory 88-Inch Cyclotron. This measurement, along with previous experimental data, suggests an energy window between 11 to 18 MeV to maximize the production and radiopurity of <figure><img></figure> . This experiment has yielded cross sections for 43 channels of deuteron-induced reactions from threshold to 30 MeV, including the first experimental results of <figure><img></figure> (d,x) <figure><img></figure> (cumulative), <figure><img></figure> (d,x) <figure><img></figure> (independent), <figure><img></figure> (d,x) <figure><img></figure> (cumulative) and <figure><img></figure> (d,x) <figure><img></figure> , <figure><img></figure> (cumulative). The results were compared with literature data, the TENDL-2023 database, and default theoretical calculations from the <span>TALYS-2.04</span>, <span>CoH-3.6.0</span>, <span>EMPIRE-3.2.3</span>, and <span>ALICE-2020</span> reaction modeling codes. This work presents another example of the lack of predictive capabilities for this set of modern nuclear-reaction modeling codes, and highlights the unsatisfactory modeling of experimental cross sections. Experimental data are important to improve the codes in general, and new experimental results can be used to improve the models. Finally, this measurement has revealed the need for an updated evaluation of the <figure><img></figure> (d,x) <figure><img></figure> deuteron monitor reaction.</div></div>","PeriodicalId":8096,"journal":{"name":"Applied Radiation and Isotopes","volume":"229 ","pages":"Article 112311"},"PeriodicalIF":1.8,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145826864","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Comprehensive assessment of shielding performance and neutron dose escalation in high-energy LINAC vaults: lessons from a radiation safety case study","authors":"Zakaria Tahiri ,&nbsp;Hamza Sekkat ,&nbsp;Reda Hallab ,&nbsp;Mohammed Talbi ,&nbsp;Hicham Harrass ,&nbsp;M'Hamed El Mansouri","doi":"10.1016/j.apradiso.2025.112400","DOIUrl":"10.1016/j.apradiso.2025.112400","url":null,"abstract":"<div><div>This analytical case study investigates a real-world shielding failure at a high-energy linear accelerator (LINAC) vault operating at photon energies up to 18 MV, focusing on neutron dose discrepancies observed at the maze door, a known vulnerability in radiotherapy room design. The study assesses how evolving clinical techniques, particularly Intensity-Modulated Radiation Therapy (IMRT) and Volumetric Modulated Arc Therapy (VMAT), impact shielding adequacy and radiation safety. A mixed-method approach was employed, combining theoretical calculations based on NCRP Report No. 151, automated Excel-based modeling and on-site radiation measurements using neutron-sensitive probes. Pre- and post-IMRT/VMAT workloads were compared and the weekly neutron dose equivalent at the maze entrance was used as the primary performance indicator. The effectiveness of borated polyethylene (BPE) shielding was evaluated under both scenarios. Following the implementation of IMRT/VMAT, the facility's weekly workload increased from 790 Gy/week to 2310 Gy/week, with the 18 MV workload increasing from 470 Gy/week to 1222 Gy/week. This resulted in a significant rise in neutron dose equivalent at the maze door, increasing from 869.5 μSv/week (pre-IMRT/VMAT) to 2260 μSv/week, a 2.6-fold increase. To maintain a conservative design dose limit of P⁄2 = 50 μSv/week, the required BPE shielding thickness increased from 55.8 mm to 74.7 mm, exceeding the door's original structural capacity. Photon and capture gamma-ray contributions were negligible. This case revealed shielding deficiencies from underestimating clinical workload and advanced modality adoption. Findings emphasize anticipatory shielding design, periodic reassessment and safety controls, crucial for facilities in low- and middle-income countries transitioning from conventional 3D-CRT to IMRT/VMAT techniques in radiotherapy.</div></div>","PeriodicalId":8096,"journal":{"name":"Applied Radiation and Isotopes","volume":"229 ","pages":"Article 112400"},"PeriodicalIF":1.8,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145916487","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A prototype of a 3D-printed zoomorphic mouse model for small animal PET scanner calibration","authors":"E.M.R. Andrade ,&nbsp;A.C.M. Silva ,&nbsp;A.V. Ferreira ,&nbsp;R.M.G. Gontijo ,&nbsp;L. Paixão ,&nbsp;T.C.F. Fonseca ,&nbsp;B.M. Mendes","doi":"10.1016/j.apradiso.2025.112362","DOIUrl":"10.1016/j.apradiso.2025.112362","url":null,"abstract":"<div><div>Positron emission tomography (PET) scanner for small animals is of great importance for developing new radiopharmaceuticals for molecular diagnosis and therapy and, thus, for potential clinical applications. The calibration procedure of these systems is essential for quantitative studies and image quality evaluation. It requires several steps, materials, and a suitable phantom. This study aimed to develop a 3D-printed mouse phantom based on the DM_BRA voxel mouse phantom and demonstrate its applicability for small animal PET studies. The physical mouse phantom consists of the 3D printing of a minimum of 2 mm thick with an empty internal cavity corresponding to the real dimensions of the DM_BRA voxel phantom. The model was impermeabilized with epoxy resin to prevent leakage. Counting efficiency and count rates performance evaluations were conducted using the PET scanner (LabPET4 Solo, GE Healthcare Technologies) at the Molecular Image Laboratory (LIM/CDTN/CNEN) in Brazil. Tests revealed that the counting efficiency of the system is about 6.4kCPS·MBq⁻¹. In general, the absolute values from DM_BRA zoomorphic phantom count rates curves are lower than those from the recommended NEMA NU 4–2008 cylindrical phantom. However, the shape of the count rates curves from both phantoms are very similar: (i) prompt curves increase up to their maximum value at 100MBq and after decrease slowly to around 90 % of the maximum value at 180MBq; (ii) true curves reached their maximum value around 100MBq, corresponding to 50 % of prompt counts; (iii) random curves reach similar plateau value around 50 % of prompt counts; (iv) NEC curves in both studies reach their maximum value at 90MBq. The study revealed that despite the lower counts rates performance, the zoomorphic model offers an anatomically representative design. Its adaptability for different radionuclides and straightforward preparation enhances its usability in routine laboratory protocols.</div></div>","PeriodicalId":8096,"journal":{"name":"Applied Radiation and Isotopes","volume":"229 ","pages":"Article 112362"},"PeriodicalIF":1.8,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145682646","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The SpekPy toolkit for modelling X-ray tube spectra: Extension to transmission targets and additional target materials","authors":"G. Poludniowski,&nbsp;A. Omar","doi":"10.1016/j.apradiso.2025.112374","DOIUrl":"10.1016/j.apradiso.2025.112374","url":null,"abstract":"<div><div>SpekPy is a software toolkit for the Python programming language and designed for modelling X-ray tube spectra. The tookit is used in industry, higher education and research around the world. Previously SpekPy has only had the capability for modelling so-called ‘reflection’ geometry X-ray tubes with thick target anodes consisting of the elements Mo, Rh or W. This work describes extensions in release v2.5 to include four new target elements – Cr, Cu, Ag and Au – as well as modifications to model transmission targets. Predictions for a variety of tubes were compared to results from simulations using the PENELOPE general-purpose Monte Carlo code system and to experimental spectra provided by a manufacturer. Agreement was excellent. If the target thickness was greater than 20% of the continuous slowing down approximation range for the material, the predicted total fluence was within 10% of Monte Carlo results and the discrepancy in spectral shape was negligible. Agreement with experimental spectra was also encouraging. The described advances will permit more types of X-ray tubes to be modelled by SpekPy, extending its usefulness to scientists in a broader range of applications.</div></div>","PeriodicalId":8096,"journal":{"name":"Applied Radiation and Isotopes","volume":"229 ","pages":"Article 112374"},"PeriodicalIF":1.8,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145767124","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Assessing gamma emitters and 222Rn exhalation in Uruguayan building materials: a comprehensive analysis","authors":"Ana Noguera,&nbsp;Rodolfo Reboulaz,&nbsp;Heinkel Bentos Pereira,&nbsp;Laura Fornaro","doi":"10.1016/j.apradiso.2025.112378","DOIUrl":"10.1016/j.apradiso.2025.112378","url":null,"abstract":"<div><div>This study provides the first report on the activity concentrations of gamma emitters (²²⁶Ra, ²³²Th, and ⁴⁰K) in building materials marketed and used in Uruguay, as well as their potential for ²²²Rn exhalation. The analyzed materials were categorized based on their use into cements and cementitious mixtures, granites, bricks and concrete blocks, ceramic and porcelain tiles, and gypsum and fiber cement. Granites were found to have the highest activity concentrations for ²²⁶Ra, ²³²Th, and ⁴⁰K, whereas gypsum and fiber cement exhibited the lowest activity concentrations for all three radionuclides. Additionally, granites have the highest potential for ²²²Rn exhalation and radiological indices. Radiological indexes and dose evaluation show that the building materials analyzed present no radiological risk.</div></div>","PeriodicalId":8096,"journal":{"name":"Applied Radiation and Isotopes","volume":"229 ","pages":"Article 112378"},"PeriodicalIF":1.8,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145787265","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Radiation anomaly detection using continuous wavelet transform and Zernike moments","authors":"Assem Abdelhakim","doi":"10.1016/j.apradiso.2026.112432","DOIUrl":"10.1016/j.apradiso.2026.112432","url":null,"abstract":"<div><div>Detecting illicit radioactive materials has been always one of the significant tasks for homeland security due to the radiation emissions of such materials that may endanger the citizens. One of the major challenges in radiation detection is to distinguish between normal or background radiation and anomalous source radiation at low source to background radiation ratios. In this paper, an effective anomaly detection method is proposed to detect anomalous Gamma-ray radiation spectra. The method is based on the continuous wavelet transform to exploit the energy-frequency characteristics of the radiation energy spectrum. A Scalogram image is generated from the transform coefficients, where image processing can be applied for extracting effective feature values. The Zernike moments of the Scalogram image are selected to represent the feature vector of the corresponding radiation spectrum. Finally, classification of the given radiation spectrum is carried out using the Mahalanobis distance that represents the anomaly score. The performance is evaluated using real measurements that are collected from a network of radiation detectors. To present the effectiveness of the proposed work, a comparison is conducted with both benchmark and recent methods in terms of the anomaly detection capabilities. Experimental results show that the proposed method achieves better performance compared to the other methods even at low source to background radiation ratios.</div></div>","PeriodicalId":8096,"journal":{"name":"Applied Radiation and Isotopes","volume":"229 ","pages":"Article 112432"},"PeriodicalIF":1.8,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145964956","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Radioprotective effects of copper and manganese Schiff base complexes against 6 MeV electron beam on breast cancers cells","authors":"Wan Nordiana Rahman ,&nbsp;Noor Nabilah Talik Sisin ,&nbsp;Raizulnasuha Ab Rashid ,&nbsp;Faizal Mohamed ,&nbsp;Fuad Ismail ,&nbsp;Khairiyah Sidek ,&nbsp;Merfat Algethami ,&nbsp;Awatef S. Assran","doi":"10.1016/j.apradiso.2025.112334","DOIUrl":"10.1016/j.apradiso.2025.112334","url":null,"abstract":"<div><h3>Purpose</h3><div>Targeting breast cancer with radiotherapy demand a strategy by maximizing high dose radiation whilst crucially ensure the neighbouring healthy tissues can be preserved and protected from radiation exposure. In order to diminish this negative effect some radioprotector element seem essential. Current approach of using metal complexes as radioprotector in radiation therapy had shown a promising outcome in advanced targeted radiotherapy.</div></div><div><h3>Methods</h3><div>Cu and Mn NPs complexation with two Schiff bases (L², and L³) were evaluated for their cytotoxicity and free radical scavenging activities using DPPH test on MCF-7 and MDA MB-123 cancer cells. The radioprotective effect with 6 MeV clinical electron beam were evaluated using clonogenic assay.</div></div><div><h3>Results</h3><div>The cytotoxicity test show that the Cu-L², Cu-L³ and Mn-L², Mn-L³ complexes are more toxic to MDA-MB-123 as compared to MCF-7 cancer cells. Mn-L² and Cu-L² are less toxic compare to Mn-L³ and Cu-L³ and were selected to be tested for irradiation study. The presence of the complexes during 6 MeV electron beam irradiation demonstrated that the Cu- L² complex protected MCF-7 cells better than the Mn-L² complex. The dose modifying ratio (DMR) measured show the value of Mn complexes is higher than that of Cu complexes. Finally, the DPPH free radical scavenging activities revealed that the Cu-L³, Mn-L³, and Mn-L² complexes had poor antioxidative characteristics, whereas the Cu-L² complex had intermediate antioxidative properties.</div></div><div><h3>Conclusion</h3><div>The Cu-L² compound is the most effective radioprotective agent compared to other compounds under investigation. The Mn-L³, Cu-L³ and Mn-L² are found to be toxic with oxidative properties that might need further investigation for clinical application.</div></div>","PeriodicalId":8096,"journal":{"name":"Applied Radiation and Isotopes","volume":"229 ","pages":"Article 112334"},"PeriodicalIF":1.8,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145676096","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effective shielding elements and oxides for medical X-ray applications","authors":"H.M. Badran ,&nbsp;M.M. Mourad ,&nbsp;T. Sharshar","doi":"10.1016/j.apradiso.2025.112402","DOIUrl":"10.1016/j.apradiso.2025.112402","url":null,"abstract":"<div><div>This study explores the potential of elements with atomic numbers 55–83 and their prevalent oxides as substitutes for lead in X-ray shielding applications, focusing on reducing mass and thickness while maintaining effectiveness across energies from 10 keV to 500 keV. The Pb-equivalent mass and thickness ratios were calculated for these elements and oxides, revealing significant variations in attenuation properties. To demonstrate the differences between broad-beam and narrow-beam attenuation as well as between mono-energetic photons and X-ray tube-generated spectra, measurements and calculations for 0.5 mm Pb were compared. Ta and W, as well as Pb and Bi oxides, are suitable substitutes at 15 keV, making them ideal for mammography. Sm, Nd, and Bi, as well as several oxides, are advisable alternatives near 50 keV, making them suitable for dental X-ray shielding. Pb and Bi oxides are preferred for CT applications, along with others, whereas Bi and W are appropriate for high-energy X-rays. The study also reveals that at low photon energies, PbO, Pb₃O₄, PbO₂, and Bi₂O₃ demonstrate optimal Pb-equivalent ratios slightly above unity. Alternatives such as WO₂ and YbO exhibit potential at elevated energies. Calculations performed using X-ray tube spectra generated at varying X-ray tube voltages indicated that PbO outperforms other oxides at lower tube voltages, while YbO excels at energies greater than its K-edge. These findings provide valuable insights for the development of Pb-free X-ray shielding solutions that can meet the demands of various medical imaging modalities, enhancing safety and efficiency.</div></div>","PeriodicalId":8096,"journal":{"name":"Applied Radiation and Isotopes","volume":"229 ","pages":"Article 112402"},"PeriodicalIF":1.8,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145833043","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}