Radiation Physics and Chemistry最新文献

{"title":"Standard-less IM-NAA for compositional analysis of nuclear reactor materials: Flux characterization and uncertainty evaluation","authors":"S.K. Samanta ,&nbsp;Purbali Das ,&nbsp;Sonika Gupta ,&nbsp;Suparna Sodaye","doi":"10.1016/j.radphyschem.2026.113657","DOIUrl":"10.1016/j.radphyschem.2026.113657","url":null,"abstract":"<div><div>The standard-less IM-NAA approach using research reactors requires characterization of the different irradiation sites with respect to neutron flux parameters, specifically the sub-cadmium to epithermal flux ratio (<em>f</em>) and the epithermal neutron flux shape factor (<em>α</em>). The flux characterization was performed at two research reactor facilities at BARC, Mumbai: the outer core irradiation position (H7) of the Apsara-U reactor and the Pneumatic Carrier Facility (PCF) of the Dhruva reactor. The accuracy and robustness of the developed methodology was validated using certified reference materials (CRMs). The optimized IM-NAA methodology was subsequently employed for the comprehensive chemical characterization of different steel samples relevant to advanced reactor technology. The uncertainty associated with IM-NAA measurements was rigorously evaluated, accounting for nuclear data parameters (e.g., <em>Q</em>_<em>0</em>, <em>k</em>_<em>0</em>, <span><math><mrow><mover><msub><mi>E</mi><mi>r</mi></msub><mo>‾</mo></mover></mrow></math></span>) reactor flux parameters (<em>f, α</em>), and other contributors often neglected in conventional analysis. The work successfully demonstrated that IM-NAA, when implemented with properly characterized flux parameters, provides a reliable, standard-less methodology for the accurate and precise compositional analysis of complex alloys, thereby strengthening quality control and material verification protocols for advanced nuclear technologies.</div></div>","PeriodicalId":20861,"journal":{"name":"Radiation Physics and Chemistry","volume":"243 ","pages":"Article 113657"},"PeriodicalIF":2.8,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146014446","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Understanding key volatiles in semi-moist pet foods treated with electron beam and X-ray irradiation","authors":"Anand Kumar Sethukali ,&nbsp;Dongbin Park ,&nbsp;Cheorun Jo ,&nbsp;Hyun Jung Lee","doi":"10.1016/j.radphyschem.2026.113689","DOIUrl":"10.1016/j.radphyschem.2026.113689","url":null,"abstract":"<div><div>In this study, semi-moist pet food samples were irradiated with electron beam and X-rays at 0, 2.5, 5, and 10 kGy. Samples were stored under refrigeration, and volatile compounds were analyzed on days 0 and 60. X-ray irradiation produced more volatile compounds than electron beam, likely due to differences in free radical formation and radiation-matter interaction characteristics. A dose of 10 kGy promoted oxidative reactions, increasing aldehydes, ketones, and carboxylic compounds, while 5 kGy resulted in more alkanes, indicating hydrocarbon breakdown and distinct flavor development. Notably, 1,3-di-<em>tert</em>-butylbenzene increased consistently at 10 kGy compared to controls, suggesting formation through packaging antioxidant degradation and migration into the fat matrix, supporting its potential role as an irradiation- and packaging-related marker in semi-moist pet foods. Storage conditions significantly influenced volatile compound changes, emphasizing the need for further investigation. These results highlight the importance of optimizing irradiation dose and storage conditions to ensure the safety and quality of semi-moist pet foods, with volatile compound profiles used as chemical indicators of potential sensory changes relevant to product quality.</div></div>","PeriodicalId":20861,"journal":{"name":"Radiation Physics and Chemistry","volume":"243 ","pages":"Article 113689"},"PeriodicalIF":2.8,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146110479","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Comparison of VOLO and sequential optimizers in CyberKnife SRS for glomus jugular tumors: Plan quality, efficiency, quality assurance and NTCP analysis","authors":"Xing Di ,&nbsp;Kan Wang ,&nbsp;Haoxin Jin ,&nbsp;Yuhui Yang ,&nbsp;Minghao Sun ,&nbsp;Yike Xu ,&nbsp;Wensa Peng ,&nbsp;Xiaoxia Liu","doi":"10.1016/j.radphyschem.2026.113643","DOIUrl":"10.1016/j.radphyschem.2026.113643","url":null,"abstract":"<div><h3>Purpose</h3><div>This study systematically compared the VOLO and Sequential (SEQU) optimizers for CyberKnife-based stereotactic radiosurgery (CK-SRS) in jugular foramen tumors (GFTs). The evaluation included plan quality, delivery efficiency, quality assurance, and normal tissue complication probability (NTCP) for xerostomia, to validate the clinical benefits of VOLO optimizer in skull-base and craniovertebral junction (CVJ) radiosurgery.</div></div><div><h3>Methods</h3><div>Eighteen patients with GFTs (PTV volume: 17.81 ± 7.97 cc) treated with fractionated CK-SRS (28 Gy/4 fractions) were included. Plans were optimized independently using SEQU and VOLO optimizers with fixed collimators (5–35 mm) and Ray-Tracing dose calculation. Plan quality was evaluated based on target coverage, conformity index (CI), gradient index (GI), coverage, dose to organs at risk (OARs) and healthy brain tissue (HBT) exposure. Delivery efficiency was assessed using the number of nodes, beams, monitor units (MU), and delivery time. Dose verification was performed using an ionization chamber for point dose comparison and EBT3 film for gamma evaluation (3 %/2 mm) of planar dose distribution. Additionally, NTCP for xerostomia was calculated based on mean doses to submandibular gland and bilateral parotid.</div></div><div><h3>Results</h3><div>VOLO optimization demonstrated superior dosimetric performance over SEQU, achieving significantly improved conformity (CI: 1.16 ± 0.06 <em>vs</em> 1.19 ± 0.69, <em>p</em> = 0.019) and steeper dose gradients (GI: 3.31 ± 0.52 <em>vs</em> 3.69 ± 0.60, <em>p</em> = 0.004) while maintaining comparable target coverage (<em>p</em> = 0.845). Meanwhile, VOLO also improved protection of most OARs and reduced exposure of HBT at intermediate-to-high dose levels. Treatment efficiency was significantly enhanced, with reductions in MU (66.89 %), beams (23.89 %), nodes (19.00 %), and treatment time (20.50 %), alongside a 41.08 % shorter optimization time (all <em>p</em> &lt; 0.001). Notably, VOLO optimization resulted in a lower predicted NTCP for both moderate-to-severe (15.69 % <em>vs</em> 16.18 %, <em>p</em> = 0.012) and severe xerostomia (3.93 % <em>vs</em> 4.05 %, <em>p</em> = 0.003). All plans passed quality assurance checks, with mean point dose differences below 2.60 % and gamma pass rates for 3 %/1 mm exceeding 95.26 %.</div></div><div><h3>Conclusion</h3><div>Compared to the SEQU optimizer, VOLO demonstrated superior dosimetric plan quality, significantly improved treatment efficiency, and reduced xerostomia risk for JFTs treated with CK-SRS. The excellent clinical performance of VOLO, further validated by all plans passing rigorous dose verification, strongly supports its adoption as the preferred optimization solution for complex skull-base and CVJ radiosurgery.</div></div>","PeriodicalId":20861,"journal":{"name":"Radiation Physics and Chemistry","volume":"243 ","pages":"Article 113643"},"PeriodicalIF":2.8,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145995423","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Validating photon beam delivery by 3D-printed head phantom","authors":"Daria Polomoshnova ,&nbsp;Angelina Bulavskaya ,&nbsp;Irina Miloichikova ,&nbsp;Faustina Ntim Opoku ,&nbsp;Sergei Stuchebrov","doi":"10.1016/j.radphyschem.2026.113683","DOIUrl":"10.1016/j.radphyschem.2026.113683","url":null,"abstract":"<div><div>The precise delivery of radiation dose to tumors while sparing healthy tissues is a cornerstone of effective radiotherapy, demanding rigorous pre-treatment validation. Dosimetric phantoms are essential tools for this validation, yet conventional designs often lack anatomical realism. This study addresses the need for more patient-specific and accessible quality assurance tools by developing and evaluating a 3D-printed head phantom. It was hypothesized that a universal head phantom fabricated via fused filament fabrication from polylactic acid could provide dosimetric accuracy comparable to clinical standards. The phantom was designed, printed, and then underwent a full cycle of radiation therapy: CT simulation, planning of radiation therapy with intensity modulation (IMRT) and arc modulation (VMAT), irradiation with photon beams of 6 and 10 MeV. Dose was measured using a farmer-type ionization chamber and radiochromic films. The results showed excellent agreement between measured and planned doses, with deviations of less than 1% for point measurements and a gamma analysis passing rate exceeding 95% (3%/3 mm criteria) for 2D dose distributions. These findings confirm that the developed 3D-printed phantom is a reliable and versatile tool, demonstrating significant potential for enhancing quality assurance procedures in clinical radiotherapy and for facilitating controlled dosimetric research.</div></div>","PeriodicalId":20861,"journal":{"name":"Radiation Physics and Chemistry","volume":"243 ","pages":"Article 113683"},"PeriodicalIF":2.8,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146095728","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effect of Europium oxide on structural, mechanical, optical, and radiation shielding properties of silver–doped oxyfluoro phospho–silicate glasses","authors":"S.A. Bassam ,&nbsp;K.A. Naseer ,&nbsp;C.S. Suchand Sangeeth ,&nbsp;Mohammed S. Alqahtani ,&nbsp;Muhammed Arshad Thottappali ,&nbsp;Mayeen Uddin Khandaker ,&nbsp;E. El Shiekh","doi":"10.1016/j.radphyschem.2026.113678","DOIUrl":"10.1016/j.radphyschem.2026.113678","url":null,"abstract":"<div><div>Five distinctive series of glasses were synthesized to investigate the effect of Eu³⁺ ions on the structural, elastic, optical, and gamma–ray shielding properties of the silver–doped alkaline oxyfluro phospho–silicate glasses, featuring a nominal composition of 50P₂O₅ + 15SiO₂ + 10BaF₂ + 10SrF₂ + (15−X) AgNO₃ + XEu₂O₃, where (X = 0.1, 0.5, 1, 1.5, and 3 wt%). The preparation was carried out with the traditional melt–quench technique, and the presence of an amorphous nature was confirmed through the XRD spectrum. The functional groups present in the glass network were identified utilizing the FTIR spectra. Some of the physical, structural, and elastic properties of the glasses were evaluated. The inclusion of Eu³⁺ ions densifies the glass matrix which significantly increases the density (2.061–2.308 g/cm³), refractive index (1.672–1.766), and elastic moduli (Young's modulus 54.1–104.1 GPa) while decreasing the molar volume (99.373–91.026 cm³/mol). These glasses are suitable for radiation shielding applications due to their enhanced effectiveness in attenuating high–energy radiation, as demonstrated by the increase in mass attenuation coefficient (MAC, up to 5.678 cm²/g at 0.0395 MeV) and the reduction in both direct (3.221–3.125 eV) and indirect (2.608–2.463 eV) optical band gaps, which indicate improved photon absorption. The results showed that the glass with the highest Eu₂O₃ content has the highest mass attenuation coefficient and thus has the best attenuation performance.</div></div>","PeriodicalId":20861,"journal":{"name":"Radiation Physics and Chemistry","volume":"243 ","pages":"Article 113678"},"PeriodicalIF":2.8,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146089319","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Assessment of mechanical properties and radiation shielding efficiency of fiber-reinforced ultra high-performance concrete: Experimental and simulation analysis","authors":"Ahmed A. Abdou Elabbasy ,&nbsp;Ahmed M. El-Khayatt ,&nbsp;Mahmoud Elsayed ,&nbsp;Hesham M.H. Zakaly ,&nbsp;A. Alkaoud ,&nbsp;Islam M. Nabil ,&nbsp;Islam N. Fathy ,&nbsp;Alaa M. Rashad ,&nbsp;Manar Ali","doi":"10.1016/j.radphyschem.2026.113640","DOIUrl":"10.1016/j.radphyschem.2026.113640","url":null,"abstract":"<div><div>This study examined the mechanical properties and γ-ray radiation shielding performance of different ultra high-performance concrete (UHPC) mixes incorporating individual and hybrid combinations of steel (SF), polyvinyl alcohol (PVA), polypropylene (PP), and natural jute fibers (JF). Radiation attenuation was assessed through experimental testing and validated using Monte Carlo (MC) simulations and Phy-X software. Results indicated that the control UHPC mix with steel fibers alone achieved the highest compressive strength of 140 MPa at curing age of 28 days. In comparison with this SF-reinforced control mix, the hybrid fiber mixtures (SF + PVA, SF + PP, SF + JF, and SF + PP + PVA + JF) exhibited reductions in compressive strength of approximately 12.4 %, 11.6 %, 15.7 %, and 21.1 %, respectively, at the same age. Tensile and flexural strengths followed a similar trend of reduction with hybrid fiber incorporation. Relative to the tensile strength value of the control mix (10 MPa), hybrid fiber combinations (SF + PVA, SF + PP, SF + JF, and SF + PP + PVA + JF) resulted in tensile strength reductions of approximately 4 %, 5 %, 8 %, and 8 %. Similarly, their flexural strengths were notably decreased by about 9.6 %, 18.4 %, 22 %, and 24.4 %, respectively, when compared to the control mix that achieved 25 MPa with only SF. While steel fibers remain the most effective, incorporating natural or synthetic fibers like jute and polypropylene can provide acceptable γ-attenuation performance, with potential advantages in cost, flexibility, and sustainability. Hybrid combinations offer a promising balance, especially when multi-functionality (e.g., mechanical strength and γ-radiation shielding) is desired. The key novelty aspect of this work lies in examining fiber type as the main affecting variable on the radiation shielding behavior of UHPC, while combining experimental testing with MC simulation and Phy-X software for radiation shielding assessment.</div></div>","PeriodicalId":20861,"journal":{"name":"Radiation Physics and Chemistry","volume":"243 ","pages":"Article 113640"},"PeriodicalIF":2.8,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146014443","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Beyond CTDIvol: Patient-specific SSDE and organ dose assessment in routine adult CT practice","authors":"Omar Bentiane,&nbsp;Omaima Khettabi,&nbsp;Omar Berradi,&nbsp;El Mehdi Sadiki,&nbsp;Fatimaezzahra Bouzzit,&nbsp;Rodouan Touti","doi":"10.1016/j.radphyschem.2026.113658","DOIUrl":"10.1016/j.radphyschem.2026.113658","url":null,"abstract":"<div><div>Computed Tomography (CT) is a key diagnostic tool in medical imaging, but concerns persist regarding radiation exposure, particularly in repeat or high-dose examinations. The CTDI_vol quantifies scanner output but does not accurately represent the patient dose. The Size-Specific Dose Estimate (SSDE) provides a more clinically relevant patient-specific dose estimate by accounting for body size and composition. This study aims to quantify the differences between CTDI_vol and SSDE in adult thoraco-abdominopelvic and abdominopelvic CT scans, compare manual and automatic methods of patient size estimation, and evaluate organ doses. A retrospective review was conducted on 52 adult CT scans (thoraco-abdominopelvic and abdominopelvic). Four patient-size metrics were collected: the manually measured effective diameter (D_eff-M), the automatically averaged z-axis effective diameter (D_eff-AZ), and two water-equivalent diameters (D_w-E and D_w-AZ). The SSDE values were calculated according to AAPM TG-204 and TG-220. The organ doses were estimated with <em>IndoseCT</em> based on Monte Carlo-derived correlations. The mean CTDI_vol was 13.0 ± 3.6 mGy, with SSDE values 31–37 % higher across all methods. D_eff-AZ was 4.7 % greater than D_eff-M, while D_w-E and D_w-AZ showed near-perfect agreement. The liver, kidneys, and bladder received the highest doses (&gt;15 mGy) as they are directly irradiated, whereas radiosensitive organs outside the primary scan field, such as the thyroid and eyes, received measurable scatter doses. SSDE provides a more accurate representation of patient radiation dose than CTDI_vol and should be integrated into routine CT protocols. Among the evaluated size metrics, attenuation-based D_w proved to be the most robust and reproducible. Incorporating organ-dose estimations and SSDE into clinical practice can enhance patient safety, optimize imaging protocols, and support compliance with radiation protection regulations.</div></div>","PeriodicalId":20861,"journal":{"name":"Radiation Physics and Chemistry","volume":"243 ","pages":"Article 113658"},"PeriodicalIF":2.8,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146014441","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Enhanced sono-radio dynamic therapy of non-small cell lung cancer using a polydopamine coated manganese dioxide-gold nanosystem: reactive oxygen species amplification and tumor microenvironment modulation","authors":"F. Mortazavi ,&nbsp;H. Haghighi ,&nbsp;P. Tamaddon ,&nbsp;A. Ketabi ,&nbsp;H. Heli ,&nbsp;N. Sattarahmady","doi":"10.1016/j.radphyschem.2026.113648","DOIUrl":"10.1016/j.radphyschem.2026.113648","url":null,"abstract":"<div><div>Radiotherapy (RT) and sonodynamic therapy (SDT) are reactive oxygen species (ROS)-dependent cancer treatments that suffer from limited efficacy in hypoxic and glutathione (GSH)-rich tumor microenvironments (TMEs). In this study, we developed and characterized a multifunctional polydopamine coated manganese dioxide-gold nanosystem (GMnD) as a dual sensitizer to enhance the therapeutic outcomes of RT and SDT in non-small cell lung carcinoma (NSCLC). Polydopamine coating enhanced the biocompatibility of the nanosystem and imparts stimuli-responsive properties. GMnD exhibited broad optical absorptions (visible to near-infrared), a narrow band gap (1.1 eV), and a high sonothermal conversion efficiency (80.7 %), enabling strong electromagnetic sensitization. On A549 NSCLC cells, the nanosystem in combination with ultrasound (US) and RT significantly increased ROS generation, and induced mitochondrial dysfunction, GSH depletion, catalase-like activity, and sonoporation. These effects led to synergistic cytotoxicity, correlating with mitochondrial membrane potential loss and decreased cell viability. In overall, GMnD presented a promising strategy for improving ROS-mediated combination therapy by modulating the hypoxic TME and disrupting mitochondrial redox balance.</div></div>","PeriodicalId":20861,"journal":{"name":"Radiation Physics and Chemistry","volume":"243 ","pages":"Article 113648"},"PeriodicalIF":2.8,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146072396","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Density-dependent dose response to field width and pitch variations in helical tomotherapy: a multi-density phantom and piecewise regression analysis","authors":"Eda Kaya Pepele ,&nbsp;Songül Barlaz Us","doi":"10.1016/j.radphyschem.2026.113682","DOIUrl":"10.1016/j.radphyschem.2026.113682","url":null,"abstract":"<div><h3>Objective</h3><div>To quantitatively evaluate the modulation of the maximum (D_max), mean (D_mean), and minimum (D_min) dose response at different tissue densities by field width (FW) and pitch factor in helical tomotherapy in a multi density phantom and to characterize the mass density dose relationship using single breakpoint piecewise linear models.</div></div><div><h3>Materials and methods</h3><div>Helical tomotherapy plans were generated on a cylindrical “cheese” phantom containing inserts with eight different mass densities representing lung, soft-tissue, and bone like regions for three FW values (1.0, 2.5, and 5.0 cm) and four pitch values. The modulation factor was maintained. For each combination, the D_max, D_mean, and D_min values for the inserts were recorded and analyzed using simple linear and single breakpoint piecewise linear models, with mass density as the independent variable and the dose metrics as the dependent variables. Model fit was assessed using the Akaike information criterion (AIC) and coefficient of determination (R²), and factor effects were evaluated using a multifactor ANOVA.</div></div><div><h3>Results</h3><div>Across all FW–pitch combinations, the mass density–dose relationship exhibited a clearly non-linear inverted V profile. Piecewise models, particularly for D_max and D_mean, outperformed linear models, with lower AIC and higher R² values. The breakpoints were mostly clustered around the water-equivalent regions. In the ANOVA, the mass density, dose metrics, and FW showed significant main effects, whereas the main effect of pitch was not significant within the investigated range of values.</div></div><div><h3>Conclusion</h3><div>The findings obtained in the multi-density phantom indicate that the dominant determinant of density dependent dose response in helical tomotherapy is tissue mass density, whereas FW and pitch behave as geometric parameters that secondarily modulate the dose response while preserving an inverted V baseline profile.</div></div>","PeriodicalId":20861,"journal":{"name":"Radiation Physics and Chemistry","volume":"243 ","pages":"Article 113682"},"PeriodicalIF":2.8,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146110484","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Unveiling the gamma rays attenuation mechanism in Szaibelyite ore-based shielding composites: The limiting role of low atomic number elements","authors":"Mengge Dong ,&nbsp;Suying Zhou ,&nbsp;Haofei Zhou ,&nbsp;G. Lakshminarayana ,&nbsp;M.I. Sayyed ,&nbsp;Xiangxin Xue","doi":"10.1016/j.radphyschem.2026.113692","DOIUrl":"10.1016/j.radphyschem.2026.113692","url":null,"abstract":"<div><div>Szaibelyite ore has been demonstrated as a cost-effective filler with excellent thermal neutron shielding properties, and the resulting Szaibelyite ore-based epoxy composites exhibit performance superior to some high-end commercial materials. However, the hazards associated with secondary radiation emitted from interactions between thermal neutrons and elements such as boron and hydrogen during the shielding process remain inadequately studied. This paper integrates experimental measurements, computational simulations, and radiation protection theory to systematically investigate the gamma rays shielding performance, attenuation mechanisms, and relevant shielding parameters (for both narrow and broad beams) of Szaibelyite ore-based epoxy composites within the 0.015–15 MeV energy range. The results indicate that while the gamma rays shielding capacity of the composites enhances with increasing Szaibelyite ore content, while <em>HVL</em>_γ of composites SE1−SE5 are between 6.5119 and 8.5366 cm, which is relatively low compared to ordinary concrete, and the protection against secondary radiation must be seriously addressed. Interpretation of the attenuation mechanisms based on elemental composition reveals that the shielding effectiveness is primarily determined by the predominant elements in the composites. Given that magnesium (Mg) is the element with the highest atomic number in the system, the fundamental reason for the weak gamma rays attenuation lies in the lack of high-atomic-number elements with strong shielding capabilities. This study provides a theoretical foundation and data support for the transformation of Szaibelyite ore into high-value shielding materials, contributing not only to the high-value utilization of boron resources and the sustainable development of the boron industry but also offering a new alternative pathway for developing low-cost, high-performance shielding materials.</div></div>","PeriodicalId":20861,"journal":{"name":"Radiation Physics and Chemistry","volume":"243 ","pages":"Article 113692"},"PeriodicalIF":2.8,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146134646","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}