最新刊期
卷 38 ， 期 2 ， 2020
- “在乙醇/水体系及N2氛围中，利用一步伽马射线辐照法将氧化石墨烯和银离子原位还原，并组装成具有三维网络结构的石墨烯/银复合多孔水凝胶（GH/Ag），通过冷冻干燥法得到石墨烯/银复合多孔气凝胶（GA/Ag）。GA/Ag对4-硝基苯酚表现出优异的催化性能，催化浓度高达2.16×10^-3 mol/L。”摘要：In an ethanol/water system and N2 atmosphere, graphene oxide and the silver ions were simultaneously reduced by a one-step gamma ray irradiation method and self-assembled into graphene/silver (GH/Ag) composite porous hydrogel materials with a three-dimensional structure. GA/Ag composite porous aerogels were obtained by the freeze-drying method. Scanning electron microscopy observed that GA/Ag composites have a honeycomb-like network structure. Transmission electron microscopy analysis revealed that silver nanoparticles have a size range of 20~60 nm. The results of X-ray photoelectron spectroscopy, X-ray diffraction and thermogravimetric analysis showed that the C element content in the GA/Ag composites increased, the O element content decreased, and Ag+ was reduced and thermal stability increased. Due to the synergistic catalysis between graphene and Ag nanoparticles, GA/Ag composites demonstrated excellent catalytic performance and catalyzed the concentration of 4-nitrophenol up to 2.16×10-3 mol/L. When the concentration of 4-nitrophenol was 0.72×10-3 mol/L, the first-order kinetic constant k was 1.53 min-1, which was higher than those synthesized by chemical methods.关键词：Gamma ray irradiation method;Graphene oxide;Silver nanoparticles;Reduction and self-assembly;Three-dimensional structure;Synergistic catalysis52|36|0更新时间：2025-02-28
RADIATION CHEMISTRY
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Radiological resistance regulatory mechanism of circRNA_017122 in bone marrow mesenchymal stem cells AI导读
“最新研究发现，骨髓间充质干细胞内circRNA_017122受辐射剂量影响，通过ceRNA机制调控miR-29b-2-5p对p53的表达，参与辐照损伤修复。”摘要：To investigate the radiological resistance regulatory mechanism of circRNA_017122 in bone marrow mesenchymal stem cells, qRT-PCR was used to detect mmu-circRNA_017122 expression in mouse bone marrow mesenchymal stem cells, following an irradiation treatment at different absorbed doses. The biological function of mmu-circRNA_017122 was predicted using TargetScan and miRanda software. Luciferase assay was used for the detection of mmu-circRNA_017122 and mmu-miR-29b-2-5p. Their binding was confirmed by RNA pull-down assay, while p53 expression and cell proliferation were detected by transfecting mmu-circRNA_017122 siRNA and mmu-miR-29b-2-5p inhibitors, respectively. The expression level of mmu-circRNA_017122 in bone marrow mesenchymal stem cells was affected by the absorbed dose. The biological software predicted that mmu-circRNA_017122 could specifically bind to mmu-miR-29b-2-5p and further affect P53 expression. Both the luciferase reporter assay and RNA pull-down confirmed this specific binding. After the simultaneous transfection of the mmu-circRNA_017122 siRNA and the mmu-miR-29b-2-5p inhibitor, both P53 expression and cell proliferation were significantly reduced. In irradiated bone marrow mesenchymal stem cells, the mmu-circRNA_017122 affected p53 expression by mmu-miR-29b-2-5p through a ceRNA mechanism, and thus participated in radiation damage repair, resulting in bone marrow mesenchymal stem cell radiosensitivity.关键词：mmu-circRNA_017122;mmu-miR-29b-2-5p;P53;Radioresistance26|24|0更新时间：2025-02-28
RADIOBIOLOGY AND RADIOMEDICINE
- “据最新研究，60Co γ射线辐照能有效降低休闲豆干中微生物存活数，8.6 kGy剂量下菌落总数和霉菌数降至10 CFU/g以下，为辐照技术在休闲豆干加工产业中的应用提供参考依据。”摘要：Hunan flavor leisure dried bean curd was irradiated by 60Co γ rays at different absorbed doses (0 kGy, 3.1 kGy, 5.9 kGy, 8.6 kGy, 11.4 kGy), and the microbial survival rate, general nutrients, physicochemical properties, texture characteristics, and sensory quality were investigated. The results showed that 60Co γ ray irradiation could effectively decrease the number of microbial survival in leisure dried bean curd, and the inhibition effect gradually increased with increasing absorbed dose. 60Co γ ray irradiation could reduce the aerobic plate count and molds to below 10 CFU/g at an absorbed dose of 8.6 kGy. The absorbed doses (D10) on aerobic bacterial count and molds of leisure dried bean curd were 1.82 kGy and 2.03 kGy, respectively. At absorbed doses less than 11.4 kGy, the 60Co γ rays had a much weaker effect on the moisture, protein, and ash content of leisure dried bean curd as compared with the control group (p>0.05), but the fat content was significantly lower than that in the control sample after irradiation at different doses (p<0.05). There were no significant changes in the amino acid content of leisure dried bean curd as compared with that in the control sample (p>0.05) at different absorbed doses. The change in the acid value of leisure dried bean curd irradiated at different doses was different from that in the control group, but there was no significant correlation between the change in the acid value and the absorbed dose. The peroxidation value of leisure dried bean curd decreased with increasing absorbed dose and was significantly lower than that in the control sample (p<0.05). The irradiation dose had no significant effect on the texture properties of leisure dried bean curd, including hardness, cohesiveness, cohesiveness, chewiness, and springiness (p>0.05). Moreover, absorbed doses less than 8.6 didn't have any significant negative effect on the sensory quality. The results showed that 60Co γ ray irradiation of leisure bean curd at doses less than 8.6 kGy would help retain its freshness during storage. The results of this research provide a reference for the application of irradiation technology in the leisure dried bean curd processing industry.关键词：Leisure dried bean curd;60Co γ ray;Irradiation sterilization;Quality44|25|0更新时间：2025-02-28
- “最新研究发现，12C6+离子束辐照极大螺旋藻可显著提高其生物量和遗传稳定性，为螺旋藻开发应用提供理论依据。”摘要：Spirulina maxima (S. maxima) was irradiated using 12C6+ ion beams at different doses, and the mutant strains were selected by plate separation and temperature treatment methods. Mutant strains with high biomass yields and increased temperature tolerance were screened out by genetic stability analysis. The culture conditions of the mutants were also optimized. Results showed that when the absorbed doses were 600 Gy and 800 Gy, the mutagenic effects on the algae strains were significant and the mortality rates were 71.84% and 78.47%, respectively. Two temperature-tolerant mutants (Sm04# and Sm21#) were obtained, which were cultured at 20 ℃ and 35 ℃ after irradiation at 600 Gy and 800 Gy. After ten generations, the biomasses of the mutants were 0.54 g/L and 0.91 g/L, respectively, which were 11.49% and 12.64% larger than the biomass of the control group, respectively. The culture conditions optimization experiment indicated that the optimum pH of both Sm04# and Sm21# was 9.0, the optimum light intensities were 70 and 80 μmol/(m2·s), respectively, and the optimum light-dark periods were 12:12 h and 14:10 h, respectively. In addition, the protein and polysaccharide contents of the two mutants were both higher than those of the control group, which provides a theoretical basis for the development and application of S. maxima using carbon ion irradiation.关键词：Spirulina maxima;Carbon ion beam;Temperature tolerance;Culture conditions optimization34|37|0更新时间：2025-02-28
RADIATION TECHNOLOGY APPLICATION
- “在核应急决策领域，专家采用蚁群算法，针对辐射环境下救援行动路径规划问题，为核应急快速救援提供决策支持。”摘要：After a nuclear accident, rescue operation path planning in the radioactive environment is an important part of the emergency response decision matrix. Considering the environmental characteristics of the radiation field, a method based on coupling the radiation field dose factor and ant colony optimization was used to plan the path under simulated time and dose numerical constraints. Using the typical radiation region of a nuclear power plant as input, equipment inspection path planning in the radiation field was simulated. The results show that the method in this paper can provide decision support for rapid response in a nuclear emergency.关键词：Nuclear emergency;Radiation dose;Ant colony optimization;Path planning63|33|3更新时间：2025-02-28
- “在1000kV/500kV同塔混压四回交流输电线路研究中，专家利用COMSOL软件分析了人体磁感应强度和感应电场强度分布，结果均低于国际限值，不会对人体造成健康威胁。”摘要：The finite-element multi-physics simulation software COMSOL was used to analyze the effects on the human body of a quadruple-circuit AC transmission line with a 1 000/500 kV dual voltage on the same tower. The magnetic induction intensity and induced electric field intensity in body tissues were calculated, and their maximum values in the human body were found to be 8.02 μT and 13.4 mV/m, respectively, under the conditions of 1 000 kV and 500 kV. These results were lower than the limits of the human electromagnetic (EM) exposure limits specified by the International Commission on Non-Ionizing Radiation Protection (ICNIRP). The case of a 1 000 kV or 500 kV single operation and nine typical phase sequence arrangements were analyzed, and the calculation results were also lower than the ICNIRP limits. Based on the results, the EM exposure generated by a quadruple-circuit AC transmission line with a 1 000 kV/500 kV dual voltage on the same tower will not pose a threat to human health.关键词：Electromagnetic environment;Body model;Public electromagnetic exposure;Induced electric field intensity;Safety assessment36|38|4更新时间：2025-02-28
RADIATION PROTECTION
- “在电磁暴露研究领域，专家通过数值模拟揭示了椭圆极化波对大鼠全身平均比吸收率的影响，为动物电磁暴露剂量评估提供了新方法。”摘要：In this report, we performed numerical simulation of electromagnetic exposure in rats using elliptically polarized waves as the source. By comparing the whole-body specific absorption rate (WBASAR) of electromagnetic exposure for multiple incident directions, it was determined that the WBASAR of elliptically polarized waves change with the polarization state, and is affected by the incident direction and the direction of rotation. Comparing this result to the irradiation results for linearly polarized waves travelling in the same direction, it was determined that the WBASAR results for electromagnetic exposure for these two cases are different under the same incident power. Moreover, the discrepancy presents different characteristics depending on the incident direction of the wave source and the relative positional changes associated with the posture of the rat. In addition, factors such as the polarized nature of the wave source, the irradiation method, and the rat itself, also caused large differences in the distribution of the average specific absorption rate of important tissues in rats. Therefore, considering the exposure results for linearly and non-linearly polarized waves, the exposure dose can be more comprehensively evaluated. The calculations presented in this report provide a method and supplemental data for the evaluation of electromagnetic exposure dose in animals.关键词：Electromagnetic exposure;Elliptically polarized wave;Linearly polarized wave;Finite-difference time-domain method;Specific absorption rate26|26|0更新时间：2025-02-28
- “在紫外线测量领域，专家提出了一种避免环境反射误差的方法，通过设置挡板准确测量直接和间接辐射照度，降低了成本，为狭小空间内测量提供解决方案。”摘要：The error caused by reflective light in ultraviolet (UV) irradiance measurement was analyzed, and a countermeasure to prevent this reflection error was proposed, which involved preventing reflection beams from reaching the probe. By setting a plate with a slot between the light source and the probe, the irradiance from the light source can be accurately and directly obtained; and with a baffle, the irradiance from the reflection beams can be accurately derived. The summation of the irradiance from the light source (45.7 µW/cm2) and the reflection beams (5.3 µW/cm2) matches the irradiance (51.0 µW/cm2) measured without anti-reflection fabrication. Setting a plate prevents the reflection error, and makes UV measurements in a small space feasible and cost effective, without sacrificing accuracy. The formulas for the calculation of the key parameters in designing the measurement system equipped with anti-reflection fabrication were derived.关键词：Ultraviolet (UV) ray;Measurement error;Irradiance;Reflection;Baffle plate27|64|0更新时间：2025-02-28
RADIATION INTERDISCIPLINARY RESEARCH
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