最新刊期
卷 38 ， 期 4 ， 2020
- “在辐射环境中，界面化学反应的研究进展被报道，专家详细讨论了H2O2在固液体系中的反应动力学和影响因素，为相关领域研究提供新方向。”摘要：Research on interface reactions in radiation environment is focused on the reaction of the radiolysis products of water and the physical/chemical changes of solid materials in the heterogeneous system. In this paper, we review the research on the reactivity of H2O2, the typical radiolysis product of water, which may trigger one or two reactions among oxidative dissolution (corrosion), catalytic decomposition, and Haber-Weiss or Fenton-like reaction in aqueous phase. The kinetics, thermodynamics, reaction mechanism, and governing factors of the above-mentioned reactions will be discussed later in detail.关键词：Radiation environment;Interface reactions;Oxidative dissolution;Catalytic decomposition;Haber-Weiss reactionCLC TL1365|76|1更新时间：2025-02-28
- “据最新研究，超积累植物和蚯蚓联合作用在放射性土壤修复中显示出应用前景，为我国核污染治理提供参考。”摘要：Radioactive contamination of soil, caused by the nuclear industry and nuclear accidents, is currently one of the hot topics in the world. This paper reviewed the application of hyperaccumulators in the remediation of radioactive soil. The joint action of hyperaccumulators and earthworms was expounded. The application feasibility of earthworm in radioactive soil remediation was analyzed. The difficulties and research emphases of earthworms application in radioactive-soil remediation. The application prospect of earthworms in the remediation of radioactive soil was examined, providing reference for the establishment of nuclear pollution control technology in China.关键词：Soil;Radionuclide;Hyperaccumulator;Earthworm;Review25|42|0更新时间：2025-02-28
REVIEW
- “科技媒体新闻记者报道：最新研究成功制备了具有温度和pH响应的高强度明胶/聚丙烯酸/聚N-异丙基丙烯酰胺形状记忆水凝胶，展现出优异的环境响应性能。”摘要：A novel gelatin/polyacrylic acid/poly(N-isopropyl acrylamide) shape-memory hydrogel (GAN) with temperature and pH response and high strength was prepared by two-step irradiation method, with gelatin as matrix, acrylic acid (AAc) and N-isopropyl acrylamide (NIPAm) as monomers, and N,N′-methlene bisacrylamide (MBA) as crosslinking agent. The structure, morphology, mechanical properties, and shape-memory behavior of GAN were investigated in detail. The results showed that GAN has a dense network structure, and excellent mechanical properties with the maximum tensile strength up to (5.4±0.3) MPa, and the maximum elongation at break of 745%. GAN’s shape recovery time at 60 ℃ and pH=12.8 can be controlled within 10 s and 15 min, with a shape fixation rate and shape recovery rate above 90%, respectively. This work provides a new method for the preparation of environmentally responsive high-strength shape-memory hydrogels.关键词：Shape-memory hydrogel;Gelatin;Acrylic acid;N-isopropyl acrylamide;Radiation synthesis32|34|0更新时间：2025-02-28
- “乙烯-四氟乙烯共聚物ETFE经不同剂量辐射后，热老化性能变化显著，120 kGy剂量下绝缘性能最优。”摘要：Ethylene-tetrafluoroethylene copolymers (ETFE) were aged at various absorbed doses (60 kGy, 120 kGy, and 180 kGy), and then, they were estimated and characterized by carbon residual rate, tensile test, thermal elongation test, volume resistivity analysis, and Fourier transform infrared (FTIR) spectroscopy. The results showed that the carbon residual rate of these aged samples increased with the absorbed dose while the thermal elongation decreased. With increasing absorbed dose and aging time, the tensile properties of the aged ETFE copolymer samples degraded, which could be attributed to chain breakage. Furthermore, the formation of crosslinking networks led to a change in the volume resistivity of the aged samples. The aging sample with an absorbed dose of 120 kGy showed the highest value and the best insulation performance. In addition, the FTIR results indicated that with increasing aging time, the amorphous structure of the aged samples first increased and then decreased.关键词：Ethylene-tetrafluoroethylene copolymer;Radiation crosslinking;Thermal aging28|54|0更新时间：2025-02-28
- “据最新报道，研究人员通过改变固化方式，显著提升了碳化硅纤维的耐热性能，为高温应用领域提供新解决方案。”摘要：Three types of SiC fibers were prepared by polycarbosilane fibers using either pure solely oxidation curing method, an oxidation-thermal curing method, or electron beam radiation curing method. The chemical compositions of the three types of SiC fibers were analyzed using an element analyzer, and their heat resistance was studied using universal tensile testing machine; X-ray diffraction and scanning electron microscope were also employed for characterization. The results showed that the samples prepared by the solely oxidation and oxidation-thermal curing methods had higher oxygen contents, and the initial mechanical strength of the samples reached 2.8 GPa; however, the heat resistance temperature was approximately 1 200~1 300 °C; the oxygen content of SiC fibers prepared by the radiation crosslinking method was only approximately 1%, meaning that it was able to maintain a stable structure at a high temperature of 1 500 °C. This work showed that the heat resistance temperature of SiC fibers can be greatly improved by changing the curing mode, without changing the composition of the original preceramic polymers fiber.关键词：Polymer-derived method;Silicon carbide fiber;Heat treatment;Radiation crosslinking38|37|0更新时间：2025-02-28
RADIATION CHEMISTRY
- “在放射治疗领域，研究者评估了金属植入物对剂量计算的影响，并探索了提高剂量计算准确性的方法。通过实验发现，金属伪影消减技术结合密度填充处理能显著提升剂量计算精度。”摘要：To evaluate the dose effects of metal implants and their artifacts in volume-modulated arc therapy (VMAT) plans and to explore the methods to improve the accuracy of dose calculations for patients with metal implants. With the ionization chamber placed in the middle of the plane, a IMRT phantom（CIRS model 002H9K, Norfolk, VA） with bilateral metal cylindrical steel inserts to simulate a patient receiving a hip replacement was scanned using a computed tomography (CT) simulator with metal artifact reduction (MAR) to obtain two image series, namely uncorrected phantom images and phantom images corrected with MAR. In the Monaco planning system, after the target area was delineated, full-arc and part-arc VMAT plans avoiding metal implants were designed, and actual measurements were then acquired. The effect of avoiding and passing metal areas on the dose calculation deviation was analyzed. In addition, 6 patients with metal nails implanted in the vertebral body were selected; a VMAT plan was designed using the CTNorm image and then copied to the CTNorm+DF, CTMAR, and CTMAR+DF images to evaluate the dose differences. In the VMAT plan, the part-arc plan that avoided metal areas on the CTNorm images reduced the dose calculation difference compared to that of the full-arc plan (4.97% vs. 6.14%). After density filling of the CTNorm images, the difference in the calculation of the full-arc plan significantly improved (2.35% vs. 6.14%), and the difference in the part-arc plan that avoided the metal area did not change significantly (4.64% vs. 4.97%). In the MAR images, the part-arc plan that avoided the metal area significantly improved the dose calculation accuracy compared with that of the full-arc plan (0.16% vs. 5.57%). The metal artifact reduction technique and density filling were applied to the corrected image. The full-arc and part-arc plans significantly improved the accuracy of the dose calculations compared with the CTNorm image plan after using MAR combined with density-filling methods (2.14% vs. 6.14% and 0.42% vs. 4.97%, respectively). In the clinical case, in all planning target volume dose parameter comparisons, the difference between the CTMAR and CTNorm calculation results was small; the Dmin, Dmean, VDp, CT Norm+DF, and CTMAR + DF were reduced relative to the CTNorm; and the CT Norm+DF and CTMAR+ DF conformity and uniformity were poor relative to those of the CTNorm. The MAR technique removed most of the metal artifacts on the CT images. Metal implants in patients are the main factor affecting the accuracy of dose calculations. Using a density-filling technique alone can also effectively improve the accuracy of dose calculations with known metal implant densities. The MAR technique combined with density filling can further improve the accuracy of dose calculations.关键词：Metal implants;Metal artifact;Dose calculation;Volume-modulated arc therapy (VMAT)32|31|1更新时间：2025-02-28
- “在宫颈癌近距离治疗领域，研究者比较了3D打印阴道模型塞插植治疗与常规三维腔内治疗的剂量学差异，发现3D打印技术能更好地保护膀胱，为临床应用提供新参考。”摘要：In this study, we aimed to determine the dosimetric differences between 3D-printing multi-channel applicator interstitial brachytherapy (3DP-ISBT) and conventional three-dimensional intracavity treatment (ICBT) for cervical cancer with a high-risk clinical target volume (HR-CTV) of 50~90 cm3, to determine the feasibility of using 3DP-ISBT, and to provide a basis for the application of 3DP-ISBT in clinical practice. The study included 27 patients with cervical cancer and an HR-CTV of 50~90 cm3 who underwent radiotherapy at Gansu Provincial Cancer Hospital between May 2017 and May 2019. Among them, 14 patients were treated with 3DP-ISBT and 13 were treated with ICBT. With a prescription dose was 6 Gy, evaluated the volume of the HR-CTV, the dosimetric differences in D90 (received absorbed dose of 90% of the HR-CTV) of the HR-CTV, bladder, and rectum. Compared with the ICBT group, the 3DP-ISBT group showed no statistical differences in volume of the HR-CTV, D90 of the HR-CTV, and D1cc, D2cc, and D3cc of the rectum (doses received by 1 cm3, 2 cm3, and 3 cm3 of the rectal volume) (p>0.05). D1cc, D2cc, and D3cc of the bladder were lower in the 3DP-ISBT group than in the ICBT group, and the difference was statistically significant (p<0.05). 3DP-ISBT for cervical cancer with an HR-CTV volume of 50~90 cm3 can meet clinical requirements. The target can be irradiated with a sufficient dose in large-volume cancer and can protect the bladder better than can ICBT, however, there are no advantages in terms of protection of the rectum.关键词：Cervical cancer;3D printing multi-channel applicator;Intracavity treatment;Dosimetry50|63|0更新时间：2025-02-28
RADIOBIOLOGY AND RADIOMEDICINE
- “在有机磷降解领域，研究人员通过离子束辐照诱变技术，成功筛选出高效降解菌株LA-1，其降解能力显著提升，为有机磷农药污染治理提供新途径。”摘要：An organophosphorus-degrading Bacillus subtilis strain was irradiated by 12C6+ ion beam and a highly efficient organophosphorus-degrading LA-1 strain was selected through selective breeding medium and shake flask experiments. The effect of organophosphorous pesticide degradation was also studied. The results showed that the highly stable LA-1 mutant strain was screened through eight generation propagation at an absorbed dose of 150 Gy. The amount of degraded organophosphorus was 161.71 mg/L, which was 2.89 times higher than that of the original strain. The degradation rates were 93.5% on phoxin and 83.6% on omethoate when the concentration reached 800 μg/mL and 400 μg/mL, respectively. The LA-1 mutant strain has a promising organophosphorus pesticide degradation rate.关键词：Ion beam irradiation;Mutation breeding;Organophosphorus pesticide degradation;Bacillus subtilis24|24|0更新时间：2025-02-28
RADIATION TECHNOLOGY APPLICATION
- “在焊接辐射防护领域，专家采用ANSYS软件模拟焊接环境，加入人体模型，对比分析磁场仿真与实测结果，验证了焊接电缆磁场对从业者健康无风险的猜想，为焊接辐射防护研究提供了新方向。”摘要：In this study, we adopted the ANSYS software to simulate the work environment and used a model to simulate the influence of radiation on the human body during welding. We perform on-site measurement of the magnetic field generated by the welding machine of a similar one. By comparing the simulation results of the magnetic flux density with the measurement results, it is concluded that the error between them is less than 10%. Then, we compare the results with the occupational exposure limit of this frequency band proposed by the International Committee on Non-Ionizing Radiation Protection (ICNIRP) —100 μT for quantitative analysis. The results indicate that when the welding power source outputs a high current (500 A) and the welding cable is near the human body, the magnetic flux density generated inside the human body reaches the experimental peak. Consequently, the maximum magnetic flux density generated by the cable on the waist, wrist, and other body parts is 63.36 μT, accounting for the ICNIRP standard of 63.36%. Hence, the magnetic field generated by the welding cable does not pose a health risk to the practitioner. When the output current of the welding cable is reduced to 400 A, 200 A, and 100 A, respectively, the generated magnetic flux density accounts for 50%, 21%, and 11% of the ICNIRP standard. Additionally, when the distance between the welding cable and human body increased to 0.1 m, these values become 13%, 5%, and 2.6%. This demonstrates that during the welding process, the change of output current has an effect on the distribution of the magnetic field generated by the welding cable. Moreover, the magnetic flux density is directly proportional to the magnitude of the current, and the distance from the welding cable determines the magnitude of the magnetic field strength at that location when a similar output current is generated, which is inversely related to the distance.关键词：Environmental monitoring;Simulation;On-site measurement;Occupational exposure;Safety standard18|78|0更新时间：2025-02-28
RADIATION PROTECTION
- “在辐照加工领域，专家详细测量分析了10 MeV电子加速器电子束能量和剂量参数，为制定和提高规范化辐照加工提供了积极意义。”摘要：In this study, the values of electron beam energy and dose parameters of a 10 MeV electron accelerator were measured and analyzed in detail in order to optimize the parameters used for equipment detection and improve the existing irradiation processing technology. First, the values of most probable energy and the average energy of the accelerator were estimated using the national standard aluminum lamination method. Then, the optimal penetration depth and depth dose distribution curves of the electron beam in four typical uniform materials of varying densities — PP (Polypropylene) plastic board, decorative low density board, PVC (polyvinyl chloride) foam board, and PVC acrylic board were measured and analyzed. The results demonstrated that the average energy of the electron beam was 9.42 MeV, which is slightly less than the most probable energy of 10.01 MeV, and it was concluded that the average energy is more suitable for the formulation of processing technology. Further, the dose uniformity ratio (DUR) was observed to be inversely proportional to the density of the medium, and their ratio values are 1.2, 1.28, 1.34, and 1.46 for the above four materials. it is opposite to gamma radiation situation. The relations between penetration depth and material density, and dose uniformity ratio and material density, were obtained via the empirical fitting method, which exhibit positive consequence with respect to the formulation and improvement of standardized irradiation processing.关键词：Electron accelerator;Most probable energy;Average energy;Dose uniformity ratio37|99|3更新时间：2025-02-28
RADIATION INTERDISCIPLINARY RESEARCH
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