最新刊期
卷 38 ， 期 5 ， 2020
- “据最新研究报道，EGCG在辐射防护领域取得显著进展，为相关疾病治疗提供新思路。”摘要：The radiation protection effect and mechanism of epigallocatechin-3-gallate (EGCG) were reviewed by analyzing and summarizing the literature. EGCG has a radiation protection effect on the hematopoietic system, immune system, and radiation lung injury, and its mechanism of action is related to its scavenging of free radicals, anti-oxidation, anti-apoptosis and other effects.关键词：Epigallocatechin gallate;Radiation protection;Free radicals;Anti-oxidation;Anti-apoptosis;DNA damage47|38|1更新时间：2025-02-28
REVIEW
- “科技媒体新闻记者报道：研究人员通过γ射线辐照引发接枝反应，制备了PVDF-g-PEGMA改性聚合物，有效提升了聚偏氟乙烯滤膜的抗污染性能。”摘要：Polyvinylidene difluoride (PVDF) and polyethylene glycol methyl methacrylate (PEGMA) were dissolved in N-methylpyrrolidone to form a homogeneous solution. The grafting reaction was initiated by γ-ray irradiation to prepare a modified polymer, PEGMA-g-PVDF. The analysis of the infrared spectra of PEGMA-g-PVDF before and after irradiation confirmed that the grafting reaction was effectively carried out. The degree of grafting (DG) of the irradiated product was determined by the quantitative analysis of F content before and after irradiation. Moreover, the effects of monomer concentration and absorbed dose on DG of the product were investigated. The results showed that DG increased firstly with the monomer concentration and absorbed dose in a certain range, and then decreased when exceeding the critical point. This paper also studied the thermal stability of the modified polymer through differential scanning calorimetry and thermogravimetric analysis. It was found that the melting point and thermal decomposition temperature of the modified polymer decreased with the increasing DGs. This result indicates that a higher DG reduces material’s thermal stability. Finally, according to the characteristics of homogeneous solution, the mechanism of graft reaction initiated by γ-ray irradiation was explained.关键词：Polyethylene glycol methyl methacrylate;Polyvinylidene difluoride;Homogeneous solution;Co-irradiation;Mechanism35|36|0更新时间：2025-02-28
RADIATION CHEMISTRY
- “在直肠癌放射治疗领域，研究者通过散射校准后的CBCT图像结合摆位误差数据，制定了CBCT计划，为患者放疗中各组织实际吸收剂量提供参考，为临床使用中定量评估治疗效果提供数据支持。”摘要：In the radiotherapy of rectal cancer, the actual dose received by the patient's body always differs from the planned design due to setup errors. Twenty rectal cancer cases undergoing RapidArc treatment were selected. The treatment plan of the pCT images was transplanted to the scatter-corrected cone-beam computed tomography (CBCT) images. Then, the dose was calculated to generate the revised CBCT plan after the raw CBCT plan was corrected using the weekly setup error data. Finally, a paired t-test was used to compare the results of the dose calculation between the CBCT and pCT plans. This showed that the dosimetric parameter average values of D2, D98, D50, CI, and HI in the target of the CBCT plan were lower than those in the pCT plan. The differences of 2.8%, 2.5%, 2.9%, 2.0%, and 4.4%, respectively, were statistically significant (p<0.001). The dosimetric parameter average values of Dmean, D5, V20, V30, and V40 in the small intestine of the CBCT plan were higher than those in the pCT plan. The differences of 3.0%, 3.1%, 2.5%, 3.1%, and 3.6%, respectively, were statistically significant (p<0.001). The dosimetric parameter average values of Dmean, D5, V20, V30, and V40 in the bladder of the CBCT plan were higher than those in the pCT plan. The differences of 3.0%, 1.8%, 0.9%, 3.2%, and 3.4%, respectively, were statistically significant (p<0.001). The difference between the left and right femoral heads was small (maximum difference: 0.3%, minimum difference: 0.1%); however, statistical significance was found (p<0.001). The comparative analysis indicates that the CBCT plan, based on scatter-corrected CBCT images combined with setup error data, provides a reference for the actual absorbed dose of each tissue in rectal cancer radiotherapy. These findings are useful for the quantitative evaluation of the therapeutic effect of radiotherapy for rectal cancer.关键词：Cone-beam CT(CBCT);Absorbed dose;Rectal cancer;Radiotherapy47|27|0更新时间：2025-02-28
RADIOBIOLOGY AND RADIOMEDICINE
- “在生物质能源领域，专家研究了稻草辐照预处理后甲酸法分离纤维素、木质素和木糖组分，为生物质资源高效利用提供新途径。”摘要：The cellulose, lignin, and xylose in irradiated rice straw were fractionated by formic acid method, and the effects of absorbed dose, reaction temperature, and reaction time on fractionation efficiency were studied. The separated components were analyzed and characterized by Fourier transform infrared (FTIR) spectroscopy. The results showed that the cellulose and xylan were degraded into water-soluble oligosaccharides after irradiation. Rice straw irradiated with 400 kGy was treated with 88% formic acid at 100 ℃ for 3 h, the lignocellulose components obtained the best separation effect: the extraction rates of cellulose, lignin, and xylose were 83.22%, 46.18%, and 89.52%, respectively; the purities of cellulose and lignin were 61.26% and 86.19%, respectively; the concentrations of xylose and arabinose in the rice straw xylose component were 7.04 g/L and 0.77 g/L, respectively. FTIR spectroscopy showed that both cellulose and lignin fractionated from rice straw by formic acid were formylated.关键词：Irradiation pretreatment;Rice straw;Lignocellulose;Formic acid fractionation21|35|3更新时间：2025-02-28
- “在生物效应研究领域，专家探讨了重离子辐照对盐生杜氏藻的影响，为绿藻光合系统响应机制提供理论和实验依据。”摘要：In this study, we aimed to explore the biological effect and photosynthetic response mechanism of heavy-ion irradiation on Dunaliella salina. Dunaliella salina was treated with different doses (0~320 Gy) of heavy-ion irradiation. The cell biomass, chlorophyll fluorescence parameters, and main photosynthetic pigments of progenies from irradiated Dunaliella salina cells were systematically measured and analyzed within 10 days of treatment. The results showed a significant increase in the biomass of cells that underwent heavy-ion irradiation at 90 Gy, 240 Gy, and 320 Gy doses compared with non-irradiated Dunaliella salina cells. In particular, the maximum biomass of irradiated cells was 1.78-fold greater than of non-irradiated cells at 240 Gy. The chlorophyll fluorescence imaging system, Water-PAM, was used to analyze the chlorophyll fluorescence parameters, including photochemical efficiency of photosystem II (Fv/Fm), actual photosynthetic activity (ΦPSII), and non-photochemical quenching capacity (NPQ) of the cells after irradiation. The results indicated that 90 Gy, 240 Gy, and 320 Gy doses notably increased the photosynthetic efficiency of Dunaliella salina. The 240 Gy dose-irradiated algal cells exhibited activated photoprotection systems more rapidly as compared to cells irradiated at other doses. Additionally, the β-carotene content of the algal cells after irradiation was measured using UV spectrophotometry. The results revealed that β-carotene production increased compared with non-irradiated Dunaliella salina cells, by 1.3 and 1.1 times with 240 Gy and 320 Gy, respectively. To our knowledge, this study investigated the dose and time response to heavy-ion irradiation on Dunaliella salina mutagenesis for the first time, and provided a preliminary theoretical and experimental basis for the response mechanism of the photosynthetic system to heavy-ion irradiation.关键词：Heavy-ion irradiation;Dunaliella salina;Photosynthetic efficiency;β-carotene26|26|0更新时间：2025-02-28
- “据最新报道，研究人员开发了一种即食小龙虾产品，通过优化油炸和杀菌工艺，显著提高了产品的感官品质和保质期。”摘要：Using freshwater crayfish as raw materials, we developed a ready-to-eat crayfish by cleaning, cooking, curing, seasoning, and sterilization. The effects of the processing parameters of frying and sterilizing on the sensory quality, moisture, color, and texture characteristics of crayfish meat were studied. In addition, the effects of electron beam irradiation (4 kGy, 6 kGy, 8 kGy) and high-pressure steam (121 ℃, 20 min) sterilization on the colony counts of crayfish meat were compared. Results showed that, as frying temperature and frying time increased, the sensory value of crayfish meat did not change obviously. The moisture content decreased, and the hardness, elasticity, and chewiness increased. Electron beam irradiation had less effect on the texture and color of crayfish meat than high-pressure steam sterilization. With increasing absorption, the effect of irradiation sterilization became more pronounced. The crayfish could be stored for 6 d at 37 ℃ with colony counts of 7.4×104 CFU/g when irradiated at an absorbed dose of 8 kGy.关键词：Ready-to-eat crayfish;Processing;Sterilization;Characteristics63|91|0更新时间：2025-02-28
- “在食品科学领域，研究人员采用γ射线辐照与球磨技术处理灵芝孢子粉，显著提高了破壁率和多糖含量。最优工艺条件下，破壁率达97.18%，多糖含量达13.230 mg/g。”摘要：To improve the wall-broken rate and polysaccharide content of Ganoderma lucidum spore powders, a combined treatment of γ ray irradiation and ball milling technique was used. Two-factor tests were conducted using the absorbed dose and the ball milling time as the test factors. The morphology and molecular structure of the Ganoderma lucidum spores were characterized using scanning electron microscope and Fourier transform infrared spectrometer tests under different treatment conditions. The results showed that when the absorbed dose was higher than 4.892 kGy, or the ball milling time was higher than 1 minute, the absorbed dose and ball milling time had significant effects on the wall-broken rate and the polysaccharide content of the Ganoderma lucidum spore powders, with the ball milling time having a greater effect. In addition, there was an interaction between the two pretreatment methods, which significantly affected the wall-broken rates and the polysaccharide contents of the Ganoderma lucidum spore powders. Furthermore, the optimal wall-broken rate of 97.18% and polysaccharide mass fraction of 13.230 mg/g were achieved when the Ganoderma lucidum spore powders were irradiated at 15.231 kGy with a ball milling time of 5 min. In addition, under these treatment conditions, the complete oval structure of the Ganoderma lucidum spores was almost completely broken. A small spike was observed at 1 456 cm-1, and a double peak was observed at 1 652 cm-1, which were completely different from the unbroken wall spores.关键词：γ ray irradiation;Ball milling;Ganoderma lucidum spore powder;New technology of wall-broken27|77|0更新时间：2025-02-28
RADIATION TECHNOLOGY APPLICATION
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Influence of total ionizing dose effects on domestic SiGe BiCMOS under different bias conditions AI导读
“据最新报道，国产0.35微米SiGe BiCMOS工艺器件在高剂量率辐照下表现出优异的抗电离总剂量效应能力，为辐射环境下的电子器件应用提供新方案。”摘要：This paper evaluates the effects of the total ionizing dose (TID) radiation 0.35 μm domestic SiGe BiCMOS devices under different bias conditions. 60Co gamma irradiation was performed at a high dose rate of 1 Gy(Si)/s. The results show that the SiGe BiCMOS devices enable excellent tolerance to total ionizing effect, reaching multi-kGy(Si) total ionizing dose tolerance, and the base currents are more sensitive to radiation. Under different bias conditions, when the total dose accumulated to 12 kGy(Si), the reverse bias irradiated damage is the largest, followed by the zero bias, and the forward bias irradiation presents minimum damage. We found that the main mechanism of TID is that the high dose rate radiation and the edge electric field introduced by the bias conditions influences the oxide trap charges and interface state generation in the oxide layer, which leads to an increase in the radiation sensitive zone of the base pole and an increase in the base current, thus reducing the current gain of the device.关键词：SiGe BiCMOS;Bias conditions;Total ionization dose (TID);Oxide trap charges;Interface states35|81|0更新时间：2025-02-28 - “在高温强辐射环境下，碳化硅中子探测器展现出优异性能。专家建立了实验测试系统，验证了探测器在不同标准源照射下的响应情况，为核辐射测量提供新方案。”摘要：Silicon carbide (SiC) neutron detector is suitable for monitoring in elevated temperature and harsh radiation environment owing to its wide band gap. An experimental test system of SiC neutron detector was established using standard radioactive sources, and the responses of SiC neutron detector irradiated by 252Cf and 60Co standard sources were investigated, respectively. It was found that the SiC neutron detector could work at a low bias voltage, the R2 value of the linear fitting between the counting rate and the incident neutron flux of the detector is 0.999 8 under the 252Cf source irradiation, which showed a very good linear relationship. In addition, the count of the SiC neutron detector under the 60Co source irradiation was observed mainly in the low-energy area, which could effectively distinguish the effect of γ-ray by setting the discrimination threshold.关键词：Silicon carbide;Neutron detector;Detection efficiency38|42|2更新时间：2025-02-28
RADIATION INTERDISCIPLINARY RESEARCH
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Rapid synthesis of covalent organic frameworks at room temperature through electron beam irradiation AI导读
“在材料科学领域，研究人员通过电子束辐照技术，在室温下快速合成二维亚胺键连接的共价有机框架（COFs），为大规模生产COFs提供新途径。”摘要：The conventional solvothermal/hydrothermal reaction method is still a mainstream approach for synthesis of crystalline porous materials such as covalent organic frameworks (COFs). Their synthesis methods often require increased temperatures, closed systems with high pressures, and long reaction times. The provision of a mild and efficient energy input system for rapid synthesis of COFs is still challenging. We present a rapid room-temperature synthesis of two-dimensional imine-linked COFs through simple electron beam irradiation. Radiation energy is used as a new energy input mode instead of the conventional heating energy for the COF synthesis. Such synthesis by electron beam irradiation can be achieved at room temperature within minutes. In addition, the process can be adapted for large-scale production. The absorbed dose has crucial effects on the properties of the synthesized COFs, such as the crystallinity, Brunauer-Emmett-Teller surface area, morphology, and thermal stability. A series of successful syntheses of COFs, including not only the known rigid COFs, but also a series of new flexible COFs, demonstrates the generality of this approach.关键词：Crystalline porous materials;Covalent organic frameworks;Electron beam;Radiation synthesis54|58|0更新时间：2025-02-28
RESEARCH HIGHLIGHT
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