最新刊期
- 摘要：Advanced composite materials for spacecraft structures encompass metallic-, ceramic-, and polymer-based composites. Ceramic and metal composites exhibit high radiation stability, of which the radiation damages are dominated by displacement damage such as defects and dislocations. Polymer composites, however, are radiation-sensitive because of their low bond energy and abundance of organic groups. Ionizing radiation induces ionization damage in polymer composites, irreversibly disrupting their chemical structures and interfacial interactions, leading to performance degradation and severely reducing the service reliability of spacecraft. Fiber-reinforced polymer composites, the most widely used polymer composites in spacecraft, have a fiber–matrix interface that serves as the critical region for load transfer. Radiation-induced damage at the interface often exerts a more significant influence on the degradation of mechanical properties of polymer composites than the individual contributions of matrix or fiber damage alone. The mechanism of radiation-induced damage at the interface is also more complex. This paper has discussed the intrinsic relationship between interfacial microstructural evolution and the degradation of mechanical properties based on reviewing the radiation-induced damage mechanisms of polymer matrix and reinforcement fibers commonly used in spacecraft. The influences of atomic oxygen and cyclic temperature fields coupled with radiation field on the degradation of polymer composites have been also summarized. This review aims to provide a fundamental understanding of the radiation-induced damage and mathematic modeling of polymer composite materials for spacecraft.关键词：Spacecraft;Polymer matrix;Reinforcement fiber;Interface;Radiation-induced damage3|0|0更新时间：2026-10-13
- 摘要：To reveal the structural and property degradation mechanisms of modified polypropylene (PP) under electron-beam irradiation, triallyl isocyanurate-modified PP (J-PP) sheets were investigated in this work. The effects of electron-beam irradiation at doses of 0 kGy, 50 kGy, 100 kGy, 150 kGy, and 200 kGy on its surface morphology, chemical structure, thermal properties and mechanical properties were studied. Scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC) and tensile tests were employed for characterization. The results show that the surface of irradiated modified PP gradually becomes rough. The carbonyl absorption peak near 1 716 cm-1 intensifies with increasing absorbed dose, indicating progressive oxidation of PP. Both tensile strength and elongation at break of J-PP decrease significantly as the absorbed dose rises. After 200 kGy irradiation, the two parameters drop from 32.76 MPa and 674.80% to 24.02 MPa and 3.10%, representing reductions of 26.68% and 99.54%, respectively. DSC results demonstrate that the melting-peak temperature, melting enthalpy and crystallinity of J-PP generally decrease while the gel content increases with higher absorbed dose. The crystallization temperature increases slightly at low absorbed doses but declines at high doses. Electron-beam irradiation simultaneously induces oxidative degradation of PP molecular chains. The cross-linked network formed with the assistance of TAIC can partially offset the adverse effect of chain scission on the load-bearing capacity of the material, yet it cannot effectively suppress the loss of plasticity caused by high-dose irradiation. This paper provides a reference for reliability evaluation and optimization of radiation-crosslinking modification processes for PP materials under electron-irradiation environments.关键词：Electron beam irradiation;Polypropylene;Triallyl isocyanurate;Radiation cross-linking;Oxidative degradation;Mechanical properties2|1|0更新时间：2026-10-12
- 摘要：Analysis of the positioning immobilization effects of head-neck-shoulder mask, thoracic-abdominal board, and neck-thorax integrated mask immobilization devices in radiotherapy for thymoma patients. A retrospective analysis was conducted on patients with thymoma who underwent radiotherapy at our center from January 2018 to February 2025, comparing differences in setup errors, and a Linear Mixed Model (LMM) was constructed incorporating patient baseline characteristics to analyze potential factors influencing setup errors. A total of 253 patients were included in the study. LMM analysis showed that in the superior-inferior (Y) direction, using the neck-thorax integrated mask group as the reference, the setup error in the head-neck-shoulder mask group increased by an average of 1.869 mm (p < 0.001), and the setup error in the thoracic-abdominal board group increased by an average of 1.324 mm (p = 0.009). In the anterior-posterior (Z) direction, using the head-neck-shoulder group as the reference, the setup error in the thoracic-abdominal board group increased by an average of 0.578 mm (p = 0.023). M1 stage was associated with an average increase in setup error of 0.731 mm in the Z direction compared with M0 stage (p = 0.031). The neck-thorax integrated mask demonstrated the highest immobilization accuracy in the Y direction, and M stage had a significant effect in the anterior-posterior direction independent of the immobilization device. Whether this geometric advantage can be translated into dosimetric benefits for organs at risk still requires verification through dosimetric studies.关键词：Thymoma;Radiotherapy;Immobilization device;Setup error16|15|0更新时间：2026-09-29
- 摘要：This study aimed to evaluate the effect of irradiation sterilization on the structural characteristics of recombinant collagen lyophilized products, as well as the safety and efficacy of this sterilization approach for such products. Recombinant collagen lyophilized samples were sterilized at an irradiation dose of 15 kGy, with non-irradiated samples set as the control group. Multiple indicators before and after irradiation were compared and analyzed, including the primary structure (via peptide mapping, peptide coverage analysis, and terminal amino acid sequencing), secondary structure, and biological properties of the samples. The results showed that no abnormal changes were found in the molecular structure or physicochemical properties of recombinant collagen after 15 kGy irradiation compared with the control group. All irradiated samples passed the sterility test and fully complied with the sterility standards for medical products. Irradiation sterilization at 15 kGy can achieve effective sterilization without impairing the quality of recombinant collagen lyophilized products, which serves as a reliable terminal sterilization method for this type of product.关键词：Recombinant collagen;Irradiation sterilization;Protein structure;Biosafety21|17|0更新时间：2026-09-24
- 摘要：This work systematically investigated the electrical degradation behavior and interface defect evolution mechanisms of p-GaN gate GaN HEMT devices under different proton energies and irradiation bias conditions. Proton irradiation experiments were conducted using 10 MeV and 60 MeV protons on devices with different on-resistances under both unbiased and biased conditions. The results indicate that proton irradiation induces a positive shift in threshold voltage, as well as reductions in saturation drain current and transconductance. Moreover, device parameter degradation is greater under low-energy irradiation than that under high-energy irradiation, and greater under biased irradiation than that under zero-bias irradiation. Low-frequency 1/f noise measurements were employed to quantitatively characterize the evolution of interface trap density at the AlGaN/GaN interface before and after irradiation, showing strong consistency with the degradation trends of electrical parameters. Further analysis reveals that proton irradiation primarily introduces electrically active defects at the channel interface, which reduce the two-dimensional electron gas (2DEG) concentration and carrier mobility, thereby leading to device performance degradation.关键词：p-GaN HEMT;Proton irradiation;1/f noise20|25|0更新时间：2026-09-21
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Control of absorbed dose for 60Co γ irradiation sterilization of SPF-grade laboratory mouse feed AI导读
摘要：To address the issues of inaccurate dose control for 60Co γ irradiation sterilization of specific pathogen-free (SPF) laboratory rodent diets and nutrient loss caused by excessive irradiation, a full-chain quality control system encompassing "source microbial control-dose calculation-process optimization-effect verification" was established based on a sterility assurance level (SAL) of 10-6 cfu/g. The results showed that after implementing three-level microbial control measures, the average initial bacterial count of the diet decreased from 2.26×104 cfu/g to 6.63×103 cfu/g. The D10 value of the microorganisms was determined to be 2.06 kGy, and the minimum required sterilization absorbed dose was determined to be 20.5 kGy, which is 18% lower than the conventional dose of 25 kGy, resulting in a cost saving of 450 RMB per ton of irradiated diet. Through process optimization of loading arrangement, automatic side-switching, and layer-changing repositioning, the irradiation dose non-uniformity ratio was 1.61, meeting the requirement of ≤2. All three batches of finished products were verified to be sterile and qualified. This scheme enables precise control of the sterilization dose, reduces irradiation-induced nutrient damage, and is suitable for large-scale production applications.关键词：60Co γ irradiation;SPF-grade laboratory mouse feed;Dose control;Bioburden;dose non-uniformity23|31|0更新时间：2026-09-18 - 摘要：This study aims to analyze the risk factors of severe acute radiation proctitis after cervical cancer radiotherapy, and create a Nomogram model for predicting the disease incidence. 330 cervical cancer patients in Chengde Third Hospital from July 2022 to July 2024 were included in the study. They were divided into a case group (n=40) and a non-case group (n=290) based on whether they developed grade Ⅲ or Ⅳ severe acute radiation proctitis after radiotherapy. The clinical data of the patients were retrospectively analyzed and compared, followed by a multi-factor Logistic regression analysis to identify disease influencing factors. Nomogram model for predicting the disease occurrence was created by using the "rms" package in R language. The predictive efficacy of the model was assessed by using ROC curve, calibration curve, and clinical decision curve. In the single-factor variance analysis, the age, diabetes, immune dysfunction and targeted therapy proportions in the case group were higher than those in the non-case group (all p < 0.05). The minimum distance from the treatment isocenter to the anterior rectal wall was lower in the case group than that in the non-case group (p < 0.05). Multivariate Logistic regression analysis identified high age (OR=3.081，95%CI: 1.216~7.805), diabetes (OR=4.870，95%CI: 1.848~12.839), immune dysfunction (OR=4.542，95%CI: 1.435~14.380), targeted therapy (OR=4.583，95%CI: 1.085~19.358), and low minimum distance from the treatment isocenter to the anterior wall of the rectum (OR=7.823，95%CI: 2.933~20.864) as the independent risk factors for severe acute radiation proctitis (all p < 0.05). Based on these independent risk factors, Nomogram prediction model was created. AUC, sensitivity, and specificity on the ROC curve were 0.844, 82.90%, and 71.83%, respectively. The calibration curve showed a good fit between predicted and actual probabilities (χ2=6.893, p = 0.773). The model curve on the clinical decision curve was higher than both the "None" and "All" lines. The analysis of risk factors for severe radiation proctitis after cervical cancer radiotherapy and the creation of Nomogram prediction model are helpful in improving disease prevention and treatment outcomes, and possess certain clinical application and guidance value.关键词：Cervical cancer;Grade Ⅲ;Grade Ⅳ;Acute;Radiation proctitis;Predict15|29|0更新时间：2026-09-17
- 摘要：To evaluate the electromagnetic exposure levels of different populations to the output cables of electric vehicle DC charging piles, based on electromagnetic dosimetry principles, models of the electric vehicle, DC charging pile, output cables, and other components were established in the finite element simulation software COMSOL Multiphysics. The internal electromagnetic exposure levels in adults and children were calculated and investigated under a 120 kW DC charging pile delivering a strong current of 250 A through a single output cable, considering various scenarios: standing at different positions in front of the charging pile, sitting in the left rear seat of the vehicle (near the charging port), and standing outside the vehicle door. These results were compared with the reference limits set by the International Commission on Non-Ionizing Radiation Protection (ICNIRP). The results show that when adults and children stand 200 mm away from the center of the charging pile screen, the peak magnetic flux density in their bodies is 60.6 µT and 24.7 µT, respectively; when adults and children stand beside the output cable, the peak magnetic flux density in their bodies reaches 1.77×10³ µT and 1.67×10³ µT, respectively; when adults and children sit in the left rear seat of the vehicle, the peak magnetic flux density in their bodies is 3.56 µT and 3.93 µT, respectively; and when adults and children stand outside the left rear door of the vehicle, the peak magnetic flux density is 66.5 µT and 350 µT, respectively. All values are far below the ICNIRP public exposure limit (400 mT). These results indicate that the output cables of the charging pile pose no risk to human health.关键词：Electric vehicle DC fast charging pile;DC charging cable;Electromagnetic exposure;Realistic human body model;Static magnetic field17|132|0更新时间：2026-09-17
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Microwave irradiation curing of unsaturated polyester/styrene resin: curing behavior and properties AI导读
摘要：To improve the curing efficiency of thermosetting resins, this study investigated the microwave irradiation curing behavior and property evolution of an unsaturated polyester/styrene (UP/St) resin. Differential scanning calorimetry (DSC) was used to determine a suitable thermal initiator, and the effects of microwave curing and thermal curing on the heating characteristics, thermal stability, and mechanical properties of the resin system were comparatively analyzed. The results showed that microwave irradiation curing significantly enhanced the curing efficiency of the UP/St resin. At a microwave power of 1 000 W, the heating rate of the resin reached 0.33 ℃/s, which was 8.46 times higher than that under thermal curing at 120 ℃. After curing for 360 s, the UP/St resin was nearly fully cured. Compared with conventional thermal curing, the microwave-cured samples exhibited higher thermal stability while maintaining comparable tensile strength and impact strength. These results indicate that microwave irradiation curing is an effective approach for achieving rapid curing of the UP/St resin system and provides a new processing reference for trenchless cured-in-place pipe repair.关键词：Microwave irradiation;Unsaturated polyester resin;Styrene;Rapid curing15|35|0更新时间：2026-09-10 - 摘要：This study aims to investigate the radiation dose of emergency abdominal‑pelvic CT examinations and explore the relationship between different requisition item settings and radiation dose in two centers. Patients who underwent emergency abdominal‑pelvic CT for clinical diagnosis in two centers in August 2025 were retrospectively screened. Ten patients' examination requisition forms and radiation dose sheets were randomly selected daily for evaluation. The requisition items in TR center included upper abdomen, upper‑abdomen plus lower abdomen, lower‑abdomen plus pelvis, and upper‑abdomen plus lower‑abdomen plus pelvis. The requisition items in RJ center included upper‑abdomen plus lower abdomen, and upper‑abdomen plus lower‑abdomen plus pelvis. One radiologist retrieved the automatically calculated volume CT dose index (CTDIvol) and dose‑length product (DLP) from the scanning workstation, and calculated the size‑specific dose estimate (SSDE) and effective dose (ED) based on effective diameter. Radiation doses were compared between different centers and requisition‑form items. A total of 295 patients in TR center and 302 patients in RJ center were enrolled. The median age was 47.0 years and 48.0 years, respectively, with males accounting for 48.5% and 56.0%, respectively. Significant differences in CTDIvol, DLP, SSDE, and ED were observed among groups with different abdominal CT scan ranges (all p< 0.05), and these metrics increased gradually as the scan range expanded. The scanning protocols involving the pelvic cavity yielded markedly higher dose levels. The DLP and ED values were the highest in the upper‑abdomen‑plus‑lower‑abdomen‑plus‑pelvis group; the CTDIvol and SSDE reached peak values in the lower‑abdomen‑plus‑pelvis group, whereas the upper‑abdomen‑only group presented the lowest values for all dose indicators. In TR center, diagnostic reports recommended extended scan ranges in only 4 examinations. More detailed requisition‑item settings enable clinicians to flexibly choose more targeted scan ranges for emergency abdominal‑pelvic CT, so as to reduce unnecessary patient radiation exposure.关键词：X-ray computed tomography;Emergency medicine;Radiation dose;Quality improvement13|36|0更新时间：2026-09-08
- 摘要：To investigate the real-time response characteristics of bipolar junction transistors (BJTs) under medium dose-rate gamma irradiation in nuclear industrial environments, in-situ irradiation experiments combined with numerical simulations were performed. NPN BJTs were irradiated using a 60Co gamma source, with real-time electrical measurements performed over a dose-rate range of 10-300 rad(Si)/s. The results show that under cutoff bias conditions, the increment of the collector-base reverse leakage current (∆ICBO) increases linearly with the dose-rate, and the current rapidly recovers after irradiation is terminated. Geant4 simulations indicate that this dose-rate dependence originates from the modulation of electron-hole pair generation rates in silicon. TCAD simulations further reproduce the experimental observations and confirm that the linear relationship between ∆ICBO and dose-rate agrees well with the Wirth-Rogers model. These results demonstrate that dose-rate is a critical factor governing the real-time radiation response of BJTs, providing experimental and theoretical support for radiation-effect modeling and real-time performance evaluation of semiconductor devices.关键词：Nuclear industry;Gamma radiation;Dose rate;Real-time response;Bipolar junction transistor41|69|0更新时间：2026-08-28
- 摘要：The radiation stability of polymer-based anticorrosive coatings is critical for the protection of industrial facilities in radiation environments. In this study, cerium dioxide (CeO2) nanoparticles were modified with 3-aminopropyltriethoxysilane (KH-550), and functionalized boron nitride nanosheets (WPU-BNNSs) were prepared using water-based polyurethane (WPU) as an agent. Both materials were incorporated into the WPU to obtain CeO2/BNNSs/WPU composite coatings. The effects of the addition of CeO2 and WPU-BNNSs on the anti-corrosion performance and radiation stability of the coating were systematically investigated. The coating structure was characterized using Fourier transform infrared spectroscopy, X-ray diffraction, and scanning electron microscopy. The coating’s corrosion resistance in a 3.5% NaCl solution was evaluated through electrochemical testing, and the changes before and after neutron irradiation (with a total fluence of 1010 cm-2) were compared. The results indicated that the composite coating exhibits optimal performance when the mass ratio of CeO2 to WPU-BNNSs is 1∶1 and the total loading is 1%. After 14 d of immersion, the low-frequency impedance modulus (|Z|0.01Hz) of this composite coating reached 3.15×106 Ω·cm2, which is one order of magnitude higher than that of pure WPU. After neutron irradiation, the impedance modulus remained at 1.72×106 Ω·cm2, representing a 45% reduction compared to the pre-irradiation value. This is significantly less than the 80% reduction observed in pure WPU, demonstrating excellent radiation stability. This study provides an optimized strategy for radiation resistant anti-corrosion coatings for metal protection in radiation environments, offering both theoretical and practical significance.关键词：Radiation stability;Water-based polyurethane;Cerium oxide;Boron nitride nanosheets;Corrosion protection57|51|0更新时间：2026-08-28
- 摘要：The thyroid gland is particularly sensitive to radiofrequency electromagnetic fields (RF-EMFs), with children and adolescents potentially facing higher exposure risks. This study employed finite-difference time-domain (FDTD) dosimetric simulations based on virtual human body models to quantitatively assess age-related differences in thyroid exposure doses from 5G Sub-6 GHz downlink electromagnetic fields. Three anatomical models were selected: Duke (34 years, adult), Louis (14 years, adolescent), and Dizzy (8 years, child). Tissue-specific absorption rate (TSAR) values for the thyroid were computed across the 0.7–4.9 GHz frequency range. The excitation source was configured as a 45° polarized plane wave, with azimuth angles scanned at 15° intervals over 360°. Azimuth-averaged TSAR values were obtained to represent idealized exposure conditions, and dose levels under safety threshold exposure scenarios were estimated according to the International Commission on Non-Ionizing Radiation Protection (ICNIRP) guidelines and the national standard GB 8702―2014. The results demonstrated that: thyroid TSAR varied substantially with incident azimuth angle, peaking at frontal incidence (~180°) and reaching minima at rear incidence (~0°), with an approximate two-order-of-magnitude difference between extremes; across the 0.7–4.9 GHz range, TSAR exhibited an overall decreasing trend with increasing frequency; thyroid TSAR was markedly elevated in children compared with adults (by 8.0–11.1 dB), with adolescents showing intermediate values (approximately 6.0–9.0 dB higher than adults); and under ICNIRP limit conditions, peak TSAR occurred at 1.8–2.6 GHz, whereas under national standard limit conditions, TSAR decreased monotonically with increasing frequency. These findings indicate significant age-related differences in thyroid exposure doses from 5G Sub-6 GHz downlink electromagnetic fields, identifying children as a sensitive population. Although newly introduced higher frequency bands do not appear to pose significant additional risks, it is recommended that age-specific exposure standards be considered in the development of electromagnetic radiation protection guidelines, and that base station siting strategies prioritize the protection of thyroid health in children and adolescents.关键词：5G Sub-6 GHz;Thyroid gland;EMF exposure;Risk assessment;Computational dosimetry study52|55|0更新时间：2026-08-25
- 摘要：The efficient extraction of uranium from aqueous solutions is critical for the sustainable development of nuclear energy. In this study, amidoxime-functionalized multi-walled carbon nanotubes (AO-MWCNTs) featuring a "polymer brush" architecture were synthesized via a catalyst-free radiation-induced grafting polymerization (RIGP) strategy. The resulting adsorbent exhibited high affinity toward U(VI), achieving an adsorption capacity of 84.30 mg/g at pH 5.0 (C0 = 12 mg/L). Adsorption kinetics and isotherms aligned with the pseudo-second-order and Freundlich models, respectively, indicating a chemisorption-dominated process on a heterogeneous surface. Furthermore, AO-MWCNTs demonstrated significant photothermal-enhanced adsorption capabilities. Under simulated solar irradiation (100 mW/cm² for 24 h), the material achieved near-complete removal of uranium (>99.99%), reducing residual concentrations below the limit of detection. This enhancement is attributed to localized interfacial heating induced by the photothermal effect of the CNTs, which accelerates ion diffusion and thermodynamically promotes the endothermic coordination reaction. X-ray photoelectron spectroscopy (XPS) confirmed that U(VI) capture occurs via stable bidentate chelation with oxime nitrogen and oxygen atoms. This study presents a viable, solar-driven strategy for the remediation of uranium-contaminated water.关键词：Uranium extraction;Carbon nanotubes;Radiation grafting;Photothermal effect;Amidoxime88|64|0更新时间：2026-08-18
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First-principles study on hydrogen diffusion behavior at AlCrTaTiZr/AlCrTaTiZrN₅ composite interface AI导读
摘要：Understanding the microscopic diffusion mechanism of hydrogen at the high-entropy alloy/nitride composite interface under extreme nuclear environment is crucial for researching hydrogen permeation resistance and radiation protection design. In this work, the special quasi-random structure (SQS) method was employed to construct supercell models of AlCrTaTiZr high-entropy alloy and AlCrTaTiZrN₅ high-entropy nitride. The optimal crystal planes and equilibrium interface spacing were screened based on surface energies and interface separation energies, thereby establishing a stable AlCrTaTiZr/AlCrTaTiZrN₅ composite interface. The interstitial site occupancy, solution energy, and cross-interface diffusion barrier of hydrogen atoms were systematically investigated using first-principles calculations. The results indicate that hydrogen atoms preferentially occupy octahedral interstitial sites in the nitride ceramic layer, whereas they tend to occupy tetrahedral interstitial sites in the alloy layer. In the interface region, the solution energies of hydrogen are entirely positive, suggesting that hydrogen segregation or retention is thermodynamically unfavorable. Furthermore, climbing-image nudged elastic band (CI-NEB) calculations confirm that the resistance to hydrogen diffusion is larger in the ceramic layer. Specifically, the migration barrier reaches a peak diffusion barrier of 0.54 eV when hydrogen diffuses from the ceramic layer across into the interface, demonstrating a significant blocking effect of the composite interface on hydrogen transport. This study verifies the pronounced hindering effect of the high-entropy composite interface on hydrogen diffusion from an atomic scale, providing a theoretical foundation for designing hydrogen permeation resistant materials.关键词：High-entropy alloy;Composite interface;First-principles;Hydrogen diffusion85|98|0更新时间：2026-08-06 - 摘要：Oxyhydroxide is regarded as a stable active substance in the oxygen evolution reaction (OER). In this study, a radiation synthesis strategy induced by γ ray was employed to synergistically activate, oxidize-reduce, and etch effects, and in situ synthesize FeO(OH) catalysts with oxygen vacancies on the surface of foam nickel (NF). Electrochemical tests demonstrated that this FeO(OH) catalyst has outstanding electrocatalysis OER performance. Compared with the traditional hydrothermal synthesis of FeO(OH), in 1 mol/L KOH electrolyte, it achieved an OER overpotential of 266 mV at a current density of 10 mA/cm2, and exhibited over 100 hours stability at a current density of 200 mA/cm2. In the simulated seawater solution (1 mol/L KOH + 0.5 mol/L NaCl), the catalyst also exhibits excellent electrocatalytic OER performance (307 mV@10 mA/cm2 and 50 h@1 000 mA/cm2). This study utilized radiation technology to in situ synthesize transition metal compounds with oxygen vacancies on the surface of NF, providing a new idea for designing high-performance water/seawater decomposition electrocatalysts.关键词：γ ray;Radiation synthesis;FeO(OH);Oxygen evolution reaction (OER)92|76|0更新时间：2026-07-30
- 摘要：High cholesterol-degrading lactic acid bacteria were bred via 12C6+ ion beam irradiation, and their in vitro cholesterol-degrading effects and probiotic functions were evaluated. By optimizing the KENJI solid screening medium, high cholesterol-degrading strains of 12C6+ ion beam-irradiated Lactobacillus reuteri JMR-01 and Lactobacillus casei SN-2 were screened based on colony diameter. The cholesterol degradation rates of the strains through different approaches were determined to explore the reasons for the improved cholesterol degradation efficiency of the mutant strains, and the probiotic functions of the strains were evaluated. The results showed that the mutation rates of strains JMR-01 and SN-2 were the highest at an irradiation dose of 300 Gy, and this irradiation dose was more favorable for obtaining mutant strains. Two high cholesterol-degrading strains, JMR-01-1 and SN-2-1, were screened, with their cholesterol degradation rates increased by 9.86% and 11.54% respectively compared with the original strains, which was mainly attributed to the enhanced cholesterol absorption of the strains. The mutant strains showed inhibitory effects on pancreatic lipase, α-glucosidase and colon cancer cells, indicating the potential to lower blood lipids and blood glucose and assist in the prevention and treatment of colon cancer. The optimized screening method in this study is efficient and feasible, and provides high-quality strain resources for functional probiotic products.In this study, high cholesterol-degrading lactic acid bacteria were obtained via 12C6+ heavy ion beam mutagenesis, and their in vitro cholesterol degradation capacity and probiotic characteristics were further assessed. By optimizing Kenji solid screening medium, mutant strains of irradiated Lactobacillus reuteri JMR-01 and Lactobacillus casei SN-2 were screened out according to colony diameter. Cholesterol degradation efficiencies under different conditions were determined to reveal the intrinsic mechanism for the enhanced degradation performance of mutants, and their probiotic potentials were comprehensively evaluated. The results demonstrated that the irradiation dose of 300 Gy yielded the highest mutation frequency for both strains, which was the optimal condition for mutant acquisition. Two excellent mutant strains, JMR-01-1 and SN-2-1, were successfully isolated. Compared with wild-type strains, their cholesterol degradation rates increased by 9.86% and 11.54%, respectively, which was primarily attributed to the improved cholesterol adsorption capability. Moreover, these mutants exerted obvious inhibitory effects on pancreatic lipase, α-glucosidase and colon cancer cells, suggesting their promising applications in lipid regulation, hypoglycemic regulation and auxiliary intervention against colon cancer. In conclusion, this optimized screening protocol is efficient and reliable, which lays a solid foundation for screening superior strains and facilitates the research and development of functional probiotic products.关键词：Lactobacillus;12C6+ heavy ion beam irradiation mutagenesis;High-efficiency cholesterol-degrading Lactobacillus strain;Probiotic function;In vitro cholesterol degrading effect94|77|0更新时间：2026-07-27
- 摘要：In this work, synchrotron small-angle X-ray scattering (SAXS) was employed as the primary characterization technique, combined with in situ tensile SAXS and wide-angle X-ray scattering, to systematically probe the microstructural damage mechanisms and evolution of deformation capacity in poly(vinylidene fluoride-co-hexafluoropropylene) P(VDF-co-HFP)-Li1.3Al0.3Ti1.7(PO₄)3 (LATP)-LiNO3 (PHLN) composite solid-state electrolytes subjected to electron beam absorbed doses ranging from 0 to 100 kGy. The results revealed that high-energy electron beam irradiation triggers main-chain scission of the polymer, disrupting the physical crosslinking network formed at the polymer-LATP particle interfaces. This phenomenon is manifested by aggravated surface defects and a reduction in the interfacial fractal dimension (Ds) from 2.63 to 2.33. In situ tensile SAXS measurements further verify that radiation-induced chain scission drastically weakens polymer chain entanglement, resulting in a significant negative correlation between deformation capacity and absorbed radiation dose, and ultimately leading to complete brittle fracture at 100 kGy. Utilizing synchrotron SAXS characterizations, this work establishes a direct correlation between molecular chain scission and macroscopic mechanical failure, offering critical experimental insights for the rational design of radiation-resistant solid-state electrolytes.关键词：Synchrotron radiation;Electron beam radiation;P(VDF-co-HFP);Solid-state electrolyte80|86|0更新时间：2026-07-23
- 摘要：Oral ulcers (OUs) are one of the most common inflammatory lesions of the oral mucosa, characterized by mucosal inflammation, tissue damage, and persistent pain. The moist and dynamic physiological environment of the oral cavity limits the retention and efficiency of locally administered therapeutic drugs, posing challenges to the clinical local intervention of OUs. In this study, γ-ray radiation polymerization technology was used to prepare an asymmetric hydrogel material (Iq-IA-AA) based on electrostatic interaction-induced phase separation. During the polymerization process, the polarity of the reaction system was regulated by the ratio of ethanol/water binary solvent. Itaconic acid (IA) and acrylic acid (AA) monomers rich in carboxyl groups were directionally introduced into the upper surface of the hydrogel to enhance mucosal adhesion; meanwhile, ionic liquid (Iq) monomers containing long hydrophobic carbon chains and double bonds settled to the bottom through phase separation polymerization to form a non-adhesive surface, thus constructing an asymmetric adhesive bilayer structure. Multiple characterization methods such as scanning electron microscopy and universal testing machine were used to investigate the effects of solvent composition and absorbed dose on the structure and properties of the hydrogel, clarify the formation mechanism of its bilayer structure, and evaluate its biocompatibility through cytotoxicity tests. The results showed that when the volume ratio of ethanol/water was 2∶8 and the absorbed dose was 50 kGy, the Iq-IA-AA hydrogel exhibited a tensile strength of (275±7.1) kPa, a shear adhesion strength of (270±1.5) kPa, and a water swelling degree of only 203.6%, without cytotoxicity, indicating good application potential in the auxiliary materials for clinical local treatment of OUs.关键词：Hydrogel;Asymmetric adhesion;Radiation polymerization;Itaconic acid87|85|0更新时间：2026-07-22
- 摘要：Polymer materials exposed to radiation-related extreme environments (e.g., nuclear power plants, space, and medical sterilization) easily undergo chain scission and radical-induced degradation under the synergistic effects of high-energy radiation, heat, and light, leading to performance degradation and failure. Radical-scavenging antioxidants can effectively quench active radicals and are crucial for enhancing the radiation stability of polymers. However, traditional experimental methods are inefficient in revealing structure-activity relationships at the molecular level, limiting the rational design of high-performance radiation-resistant antioxidants. In this study, quantum chemical calculations were performed to construct a dataset of 189 phenol-, amine-, thiol-based antioxidants and their derivatives. Four key descriptors, including bond dissociation energy (BDE), single electron transfer energy (SET⁺), hydroxyl radical affinity (RAF-OH), and methyl radical affinity (RAF-CH₃), were systematically calculated. The intrinsic relationship between molecular structure and radical scavenging activity was analyzed using statistical methods, and the structure–activity rules for radiation-induced ground-state radical processes were determined. Results show that BDE exhibits high dispersion and acts as the core descriptor for hydrogen transfer activity. RAF-OH and RAF-CH₃ are highly concentrated, indicating strong radical addition capability. SET⁺ shows a narrow distribution as a common electronic feature but still provides a refined auxiliary optimization direction in a small range. Antioxidants present distinct performance stratification: BDE strongly depends on functional groups, SET⁺ shows moderate differentiation, and RAF is robust with little class difference. The effect of functional group count on BDE is type-dependent. Accordingly, a multi-mechanism synergistic design strategy is proposed, using radical affinity as the foundation, BDE as the tuning target, and SET⁺ as the auxiliary factor. This work provides theoretical support for the rational design and high-throughput screening of long-acting antioxidants, helping improve the service stability of polymers under radiation aging.关键词：Density functional theory;Descriptors;Free radical antioxidant;Structure-activity relationship;Molecular design82|100|0更新时间：2026-07-17
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