最新刊期
卷 39 ， 期 4 ， 2021
- “X射线辐照合成金纳米颗粒研究取得进展，为高效合成金纳米颗粒提供参考，对原位XAFS技术探索成核机理予以展望。”摘要：X-ray irradiation offers a promising avenue to expedite the green synthesis of nanoparticles with high efficiency, simplicity, and environmental friendliness. X-ray technologies, such as X-ray photoelectron spectroscopy (XPS), X-ray absorption fine structure (XAFS), and synchrotron X-ray technologies are utilized to explore the structural evolution of nanoparticles. We summarize numerous studies concerning X-ray-induced synthesis of gold nanoparticles. Further, we discuss the nuclear growing mechanism—radiolysis and conventional wet synthesis—explored via in situ XAFS analysis. Lastly, we propose the improvement of radiolytic synthesis and the application of in situ XAFS.关键词：Gold nanoparticle;X-ray absorption fine structure (XAFS);X-ray irradiation150|385|0更新时间：2025-03-01
REVIEW
- “在材料科学领域，研究人员采用电子束辐射接枝技术，成功改善了聚四氟乙烯板材的表面特性，显著提升了其黏接性能。”摘要：The surface of polytetrafluoroethylene (PTFE) was modified by electron beam-induced grafting of acrylic acid. The change of related groups in Fourier-transform infrared spectrum indicated that acrylic acid was introduced on the PTFE surface. The influence of irradiation and grafting parameters on the extent of grafting were studied by single factor analysis, and the following optimal radiation-induced grafting conditions were determined: absorbed dose of 18 kGy, acrylic acid solution concentration of 60%, and reaction temperature of 70 ℃. Moreover, the surface water contact angle test showed that the surface wettability of PTFE after modification by radiation-induced grafting improved compared with that before modification (the water contact angle dropped from 120° to 60°). The bond strength of the modified PTFE reached 23 N/cm2.关键词：Electron beam;Radiation-induced grafting;Polytetrafluoroethylene;Bond strength127|279|0更新时间：2025-03-01
RADIATION CHEMISTRY
- “据最新研究，长期低剂量电磁辐射对发育期大鼠学习认知能力影响不大，但会导致胆碱能系统与神经递质水平紊乱。”摘要：To provide experimental evidence that defines the safety limits of electromagnetic exposure, the effects of long-term and low-dose electromagnetic irradiation during the developmental stage of free-move behaving Sprague Dawley (SD) rats on their learning and cognitive abilities were investigated. A 1.8 GHz electromagnetic wave was used as the irradiation source, and the absorbed dose was set at 0.40 W/kg during the 8-hour working time and 0.08 W/kg during the rest time of the day, the whole irradiation was continuously administered for 4 weeks. The water maze experiment was performed to detect the learning and memory ability of the rats. The chemical colorimetric method was used to measure the level of cholinergic markers, the level of monoamine neurotransmitters, the activity of antioxidant enzymes, and the concentration of oxidative stress products in the hippocampus of the rats. In addition, the hippocampal tissue was sectioned, stained, and observed under an optical microscope. The results showed that the hippocampal tissue in the brain of the exposed group was not significantly different from that of the sham group, but the content of cholinesterase was reduced and the content of acetylcholine and the activity of acetylcholine transferase were increased in the exposed group. The contents of the neurotransmitter dopamine and serotonin (5-HT) were also significantly higher in the exposed group than those in the sham group. The water maze test results showed that there was no significant change in the behavior of rats in the exposed group. Although long-term and low-dose electromagnetic radiation can cause disorders of the cholinergic system and neurotransmitter levels in SD rats, the changes in these indicators did not cause a decline in the learning and memory ability of rats, and the levels of cholinergic system markers and neurotransmitters returned to normal after 14 days.关键词：Low-dose radiation;Morris water maze;Cholinergic system;Oxidative stress;Neurotransmitters161|85|0更新时间：2025-03-01
- “在放射性皮肤损伤领域，研究者通过不同剂量60Co γ射线照射Wistar大鼠，建立了放射性皮肤损伤模型，揭示了损伤发生发展的特点和规律，为相关研究提供了新方向。”摘要：Wistar rats were irradiated with different doses of 60Co γ rays to establish models of radioactive dermatitis to exploring the development of their characteristics and rules. Twenty-six Wistar rats were randomly divided into three groups: normal control (NC) (n=6) , rad 30 Gy (n=10), and rad 45 Gy (n=10) groups. The rad 30 Gy and 45 Gy groups received a single dose of local irradiation to the buttocks, respectively. Changes in irradiated skin, body weights, and skin blood flow were observed on the 7 th, 14 th, 21 st, 28 th, 35 th, 45 th, and 60 th day after irradiation. Irradiated skin tissue samples were collected for H&E staining on the 60 th day to analyze the resultant pathological changes. Compared to the NC group, the rad group suffered distinct degrees of skin injury, which were severe on the 21 st day, followed by gradual recovery. Skin blood flow of the buttocks in erythematous hyperemia and early healing were increased, whereas its decrease in ulcers necrose and late healing. H&E staining demonstrated epidermal thickening and increase in the number of squamous epithelial cells in the rad 30 Gy group and marked epidermal thicking and dermal inflammatory cell infiltration in the rad 45 Gy group. Better model of radioactive dermatitis may be obtained by using rad 45 Gy 60Co γ rays on the skin of the buttock of Wistar rats for a singe dose of local radiation.关键词：60Co γ rays;Radiation-induced skin injury87|135|1更新时间：2025-03-01
- “在放疗领域，研究者利用Geant4软件对比不同空腔模型对剂量分布的影响，为浅表肿瘤放疗计划提供指导。”摘要：To investigate the effects of “cavity under bolus” on dose distribution, we compared and analyzed the difference in dose distribution in the water phantom in the presence and absence of cavities using the Geant4 Monte Carlo package. The model of the linear accelerator head was built using Geant4, and the phase space file of the radiation particles under the model was obtained by simulating the process of electron hitting the target. A 30 cm× 30 cm×30 cm water phantom with a center coinciding with the field center was built; its upper surface was located at the source-axis level and was vertical to the incoming ray. A 0.3-cm, 0.5-cm, or 1.0-cm bolus was built on the upper surface of the phantom. For each bolus, there were a control model and several models with cavities. The bolus was close to the phantom in the control model, and there were different cavity thicknesses between the bolus and the phantom in the models with cavities. The central-axis and shallow off-axis doses of the phantom in different models were calculated based on the phase space file; the doses for the models with cavities were compared based on the results of the control model. The results showed that thicker cavities were associated with greater effects on the central-axis and shallow off-axis doses. If the cavity thicknesses were 0.2 cm, 0.3 cm, and 0.5 cm for the 0.3-cm, 0.5-cm, and 1.0-cm boluses, the largest effect of the lower dose were 2.97%, 2.86%, and 3.45%, respectively. The cavity thickness increased with the rapid increase in the magnitudes of the effects. If the thicknesses of the cavities were the same, the effects of the central-axis doses were the greatest on the 0.5-cm bolus, followed by the 1.0-cm and 0.3-cm boluses, and those of the shallow off-axis doses were the greatest on the 0.3-cm bolus, followed by the 0.5-cm and 1.0-cm boluses. When planning, a suitable thickness of the bolus should be selected based on the tumor location. Technicians should be extremely careful when placing the bolus to ensure the cavity thickness is less than half of the bolus thickness.关键词：Bolus;Cavity;Shallow dose;Geant4127|159|2更新时间：2025-03-01
- “在皮肤损伤研究领域，专家建立了放射性皮肤损伤细胞模型，考察了60Co γ射线对HaCaT细胞的损伤及机制，为放射性皮肤损伤研究提供新思路。”摘要：The aim of this study was to investigate the damage caused to HaCaT cells by 60Co γ-rays at different doses and the underlying mechanism and to establish a cell model of radiation-induced skin injury. HaCaT cells were irradiated with a single dose of 60Co γ-rays (the radiation source was 3 m away from the cells, and the dose rate was 100.68 cGy/min). The cell activity was detected using the CCK-8 method, the vitality of superoxide dismutase (SOD) was measured using the water soluble tetrazolium salt staining method, the malondialdehyde (MDA) level was determined using the thiobarbituric acid method, the apoptosis rate was monitored through flow cytometry, and the expression of the apoptosis- and inflammation-related proteins was detected via western blotting. After irradiation with 60Co γ-rays at 18 Gy for 24 h, the morphology of HaCaT cells changed significantly, cell activity decreased to 57.5%, MDA level increased to 66.28 µmol/mg, inhibition rate of SOD increased to 32.12%, apoptosis rate increased to 18.05%, and expression of inflammatory factors increased. After incubation for 24 h at an absorbed dose of 18 Gy, the cellular models of radiation-induced skin injury were established. The mechanism of cell injury may be related to cell oxidative damage, apoptosis, and inflammatory reaction.关键词：Radiation-induced skin injury;60Co γ-ray101|74|0更新时间：2025-03-01
- “在超高真空条件下，低能电子照射质粒DNA，揭示了DNA损伤的量子产率与电子能量的关系，为电离辐射导致DNA多重损伤的机制研究提供了新见解。”摘要：Five monolayer plasmid DNA films were irradiated by low-energy electrons (LEEs) (1~20 eV) in ultra-high vacuum. Crosslinks, single-strand breaks, double-strand breaks and the loss of the supercoiled configuration were analyzed via agarose gel electrophoresis. Base damages were revealed by Escherichia coli base excision and repair endonucleases (Nth and Fpg). The electron energy dependence for the effective yields of various DNA damages showed that no clustered damage within 20 base pairs could be caused by electrons <4 eV. Crosslinks, SSBs, base damage-related crosslinks, and isolated base modifications had maxima at 5 eV and 10 eV, while the peak of DSB and non-DSB clustered damage occurred at 6 eV and 10 eV. These maxima are ascribed to core-excited resonances, which decay into bond-breaking channels leading to DNA damages. The mechanism of DNA clustered damage induced by a single LEE is elucidated through the process of the formation of transient anions and the subsequent electron transfer.关键词：DNA;Clustered damage;Low-energy electrons;Transient anions;Ionizing radiation99|136|0更新时间：2025-03-01
RADIOBIOLOGY AND RADIOMEDICINE
- “在食品科学领域，研究人员从黄芪中提取出两组大分子黄芪多糖，并研究了γ射线辐照对其分子量、结构和抗氧化活性的影响。结果表明，辐照后黄芪多糖分子量降低，抗氧化活性增强。”摘要：Two groups of high molecular weight Astragalus polysaccharide (APS), APS 1 (molecular weight of 1.93×106) and APS 2 (molecular weight of 3.92×105), were isolated from Astragalus membranaceus, and the two aqueous polysaccharide solutions were treated with γ-irradiation at absorbed doses of 1~20 kGy. We studied the irradiation impact on APS molecular weight, structure composition, and recovery using gel permeation chromatography, high-performance liquid chromatography, and Fourier transform infrared spectrometry analyses. We compared the antioxidant activities of different molecular-weight APS before and after irradiation via the 1,1-diphenyl-2-picrylhydrazyl (DPPH) inhibition rate. The results showed that the molecular-weight of APS 1 rapidly degraded to 2.33×104 with the increase in absorbed dose, and the polysaccharide recovery rate was decreased to 44.7%. The molecular weight of APS 2 decreased rapidly from 3.92×105 to 2.54×104, and the polysaccharide recovery rate decreased to 39.2%. The APS molecular weight could be effectively reduced gradually at a low absorbed dose with a high recovery rate by controlling the polysaccharide concentration. The monosaccharide composition and polysaccharide structure were essentially the same before and after the irradiation-induced degradation. The inhibition rate of APS 1 increased from 3.55% to 20.53% with the decrease in molecular weight. Finally, the DPPH inhibition rate of APS 2 increased from 15.23% to 29.61% with the decrease in molecular weights.关键词：Astragalus polysaccharide;Irradiation;Degradation;Molecular weight;Antioxidant176|178|2更新时间：2025-03-01
- “在产品质量检测领域，专家开发了电子束辐照加工产品质量厚度检测方法，为产品剂量分布测量及辐照工艺方案制定提供指导。”摘要：To quickly obtain the mass thickness and predetermine dose distribution of electron beam irradiated products, a new detection method was developed based on X-ray detection technology. The detection method was developed and optimized using four standard modules (aluminum sheet, aluminum ladder, polymethyl methacrylate sheet, and polymethyl methacrylate ladder). The accuracy and applicability of the method was verified using uniform materials (water and millet) with varying thickness and two practical materials (potato starch and frozen shrimp). For standard module and homogeneous materials, the results indicated that the relative error of the measurement and standard values was within the range of -5% to 5% for a value of mass thickness greater than 1.0 g/cm2, which indicated the reliability of the mass thickness detection method. The use of potato starch and frozen shrimps proved that the method could accurately predict the mass thickness distribution of heterogeneous products; furthermore, the method was instructive for the measurement of the actual dose distribution and radiation process design of the product.关键词：Electron beam radiation processing;Mass thickness;Electron beam accelerator;X-ray detection152|279|3更新时间：2025-03-01
RADIATION TECHNOLOGY APPLICATION
- “在电磁场安全领域，专家利用COMSOL软件建立仿真模型，研究220kV交流输电线下人体头部电磁场分布，为高压输电线电磁安全提供依据。”摘要：High-voltage AC transmission lines are one of the important factors that produce power frequency electromagnetic exposure environmental problems. To investigate the safety of the electromagnetic exposure of a human head under high-voltage AC transmission lines, this study considers 220 kV AC transmission lines as the research object; employs COMSOL Multiphysics to establish a three-dimensional, finite element simulation model of a human head under AC transmission lines, exposed to a power frequency electromagnetic field; calculates the electromagnetic field distribution around the human head for various distances; and judges the safety of the electromagnetic exposure of the human head. The results demonstrate that the shape of the head affects the distribution of the electric field. The intensity of the electromagnetic field around the head corresponds to the distance between the transmission lines and the head. The farther the transmission line is from the head, the weaker is the electromagnetic field around the head. According to the International Commission on Non-Ionizing Radiation Protection guidelines and GB 8702—2014 standard, respectively, the minimum safe distance between the head and the electric field, when the lines are grounded, is 11.0 m and 11.5 m, and when the lines are ungrounded, 10.5 m and 12.0 m. The flux density around the head is less than these two standard limits.关键词：220 kV AC transmission lines;Power frequency electromagnetic exposure;Finite element simulation;Three-dimensional human head mode144|296|0更新时间：2025-03-01
RADIATION PROTECTION
- “东方超环硬X射线诊断系统研究进展，专家验证了不锈钢和钨材料对X射线、γ射线诊断影响，为诊断系统设计提供解决方案。”摘要：Attenuation coefficients of γ-rays in stainless steel, lead, and tungsten were calculated theoretically. According to the theoretical calculations, cylindrical lead shielding and a collimator were designed for a high-energy hard X-ray spectrum diagnostic system in the Experimental Advanced Superconducting Tokamak (EAST). The hard X-ray diagnostic system of EAST was introduced in detail, and the diagnostic system was tested through table experiments with radioactive 22Na sources. Attenuation coefficients of γ rays in stainless steel and tungsten were also obtained by fitting γ-ray radiation spectra. The effect of the stainless steel and tungsten materials on the X-ray and γ-ray diagnostic system was evaluated by γ-ray energy spectra. The attenuation coefficients obtained through the experiments were found to agree well with those calculated theoretically considering the error. The influence of stainless steel on low-energy X-ray or γ-ray diagnostics cannot be ignored, while its influence on high-energy X-ray or γ-ray diagnostics can be ignored. The influence of tungsten on X-ray or γ-ray diagnostics cannot be ignored. However, high Z materials such as tungsten and lead should be avoided in front of the collimation hole of the detector to reduce the influence on diagnostic data.关键词：Tokamak;Hard X-ray;Tungsten;Stainless steel;Attenuation coefficient110|206|1更新时间：2025-03-01
- “美国亚德诺半导体技术有限公司12位模拟数字转换器AD574在60Co γ辐照条件下累积400 Gy（Si）电离剂量后，输出码值翻转向中心码值右侧偏移，同时造成翻转次数的改变。初步分析认为该现象与模拟/数字转换器内部比较器单粒子瞬态的敏感性有关。”摘要：This study investigates the AD574, a 12-bit analog/digital converter (ADC) produced by American Analog Devices, Inc. (ADI) using bipolar/I2L technology. The test samples are subjected to a total ionizing dose (TID) of 400 Gy(Si) under 60Co γ irradiation. The samples with and without the TID are then subjected to a single-event upset (SEU) test, and the upset times of the output codes under the input signal conditions of 0 V, 1 V, and 2.5 V are obtained. The test results indicate that, after accumulating a total dose of 400 Gy(Si), the upset of the AD574 output code shifts toward the right of the center code value, resulting in a change in the upset times. Furthermore, the mechanism of the TID-SEU synergistic effect for the AD574 is preliminarily analyzed; it is believed that this phenomenon is related to the sensitivity of the ADC internal comparator single-event transient (SET). The amplitude and width of the SET pulse of the comparator with the TID increase significantly; this causes a change in the AD574 output code value upset distribution and the number of upset times. This study on the TID-SEU synergistic effect serves as a useful reference for aerospace components with radiation hardness.关键词：AD converter;Total ionizing dose;Single-event upset;Synergistic effect98|179|0更新时间：2025-03-01
RADIATION INTERDISCIPLINARY RESEARCH
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