最新刊期
卷 40 ， 期 6 ， 2022
- “据最新报道，研究人员成功开发了耐高温、耐辐射的橡胶复合材料，为高温油封、电子元件热界面材料等领域提供新解决方案。”摘要：The development of heat- and radiation-resistant rubber composite materials is a key future research direction for advanced rubber materials. In this work, raw acrylic rubber (ACM) prepared via emulsion polymerization was first melt-blended with hexagonal boron nitrite (BN) particles with average particle sizes of 0.25 μm, 1.00 μm, and 10.00 μm (which were correspondingly labeled as BN-0.25, BN-1, and BN-10) and then in situ cured to obtain a variety of BN/ACM composites. The effects of mass fraction and particle sizes of BN fillers, as well as γ radiation on thermal stability, conductivity, electrical resistivity, and mechanical properties of BN/ACM composites were investigated. The results showed that when the mass fraction of BN was less than 40%, the thermal stability, conductivity, and electrical resistivity of BN/ACM composites increased with mass fraction and particle sizes of BN. At a mass fraction of BN-10 of 40%, the thermal conductivity of BN-10/ACM composites was as high as 1.438 W/(m·K), which exceeds that for high thermal conductivity polymer materials (>1 W/(m·K)). The mechanical properties, such as tensile strength and elongation at break, also increased with the increase of the mass fraction and the decrease of the particle sizes of BN. When the mass fraction of BN reached 40%, the overall mechanical properties of composites worsened due to the agglomeration of BN particles. The γ radiation effect on ACM and BN/ACM composites was studied. The results showed that when the absorbed dose reached 200 kGy, the thermal stability and conductivity of ACM and BN/ACM composites were improved, while electrical resistivity slightly decreased. Pure ACM matrix showed a tendency of hardening under γ radiation through crosslinking, resulting in decreased tensile strength of BN/ACM composites. However, the tensile strength and elongation at a break of the BN/ACM composites irradiated by γ-ray remained as high as those of the pure ACM, when the mass fraction of BN was less than 20%. Our results indicated that a BN particle size of 10 μm and mass fraction of 30% were optimal in the preparation of BN/ACM composites with a good radiation resistance and high thermal conductivity. This work provides theoretical and experimental guidance for the development of ACM composites with high thermal conductivity and radiation resistance for high-temperature oil seals, thermal interface materials for electronic components and high-energy radiation environment.关键词：Acrylic rubber (ACM);Hexagonal boron nitride;Thermal conductivity;Radiation resistance392|530|1更新时间：2025-02-28
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Damage of γ ray irradiation to properties of Ce doped bismuth titanate ferroelectric thin films AI导读
“在铁电薄膜领域，研究人员采用溶胶-凝胶法制备BCTO薄膜，并通过γ射线辐照研究其性能变化，为提高薄膜稳定性提供新思路。”摘要：A series of ferroelectric thin films of Bi3.25Ce0.75Ti3O12 (BCTO) was deposited on a composite substrate of Pt/Ti/SiO2/Si through the sol-gel method, and the deposited films were irradiated with different doses of gamma rays. The crystal structure, surface morphology, ferroelectricity, leakage, and anti-fatigue properties of the deposited films before and after irradiation were compared by thermogravimetric differential scanning calorimetry (TG-DSC), X-ray diffraction (XRD), scanning electron microscope-energy dispersive spectrometer (SEM-EDS) and ferroelectric tester. The results showed that an increase in absorbed γ ray doses, didn't change the crystal structure of films. The ferroelectricity of the deposited films decreased significantly with the residual polarization 2Pr decreasing from 51.5 μC/cm2 to 23.7 μC/cm2. The leakage current density of the films increased slightly from 0.9×10-7 A/cm2 to 7.2×10-7 A/cm2. Some of the films showed fatigue performance after 1012 polarization switching cycles.关键词：Gamma ray;Bi3.25Ce0.75Ti3O12 ferroelectric thin films;Ferroelectricity;Leakage current;Fatigue performance127|310|0更新时间：2025-02-28
RADIATION CHEMISTRY
- “最新研究发现，二甲双胍联合单次高剂量放疗可增强对小鼠非小细胞肺癌的毒性，为未来临床应用提供理论和数据支持。”摘要：To explore the therapeutic effect of metformin combined with single high-dose radiotherapy in mice with non-small cell lung cancer and the mechanism involved. In vitro cell test: the cytotoxicity of metformin under different oxygen and glucose contents was evaluated using cell survival curves. In vivo xenograft tumor test: NSCLC-A549 cells were injected into mice, which were then divided into the following five groups: control group, metformin group, single high-dose radiotherapy group, metformin 1 h before radiotherapy group, and metformin 24 h after radiotherapy group. Growth of the tumor was evaluated in each group, and the blood flow and histology of the tumor tissues were analyzed. According to the in vitro test results, metformin was the most cytotoxic under hypoxic and low-glucose conditions. The in vivo results showed that the tumor volume was the smallest in the mouse groups administered metformin 1 h before high-dose radiotherapy and 24 h after radiotherapy ((0.47±0.12) cm3 and (0.49±0.21) cm3, respectively). Blood flow analysis showed that single high-dose radiotherapy destroyed the micro-vessels of tumor tissue and reduced the perfusion of oxygen and glucose. Histological analysis revealed that cells in hypoxic and hypoglycemic area of the tumor tissue center were preferentially killed by metformin, whereas there were viable cells in the surrounding well perfused areas. Metformin combined with single high-dose radiotherapy enhanced the toxicity by changing tumor cell metabolism. These results provide theoretical and data support for the future use of metformin combined with stereotactic body radiotherapy.关键词：Non-small cell lung cancer;Metformin;Single high-dose radiotherapy;Action mechanism171|107|1更新时间：2025-02-28
RADIOBIOLOGY AND RADIOMEDICINE
- “据最新研究，中药灭菌技术多样，专家分析了辐照、微波等方法，为中药安全性提供参考，推动中药现代化发展。”摘要：Traditional Chinese medicine (TCM) is applied in various forms, such as decoction pieces, raw powder, extract, and patent Chinese medicine, etc. Controlling exogenous microbial contamination, ensuring the safety and effectiveness of traditional Chinese medicine, and selecting the appropriate sterilization technology are the key factors regarding its use. In this study, the literature on sterilization of TCM published from 2001 to 2021 was retrieved from CNKI, Wanfang, VIP, and Web of Science. Subsequently, visualization analysis software named VOSviewer and CiteSpace were used to analyze the application status and trend in TCM sterilization methods in the past 20 years. After screening was performed, 322 studies were included. The journal that published the highest number of studies on TCM sterilization was Electromechanical Information. The author's cooperative network analysis found that the Chinese medicine sterilization field mainly formed the China Institute for Food and Drug Control and Guangzhou Institute for Drug Control and other core research teams. Keywords in the literature show that the research on TCM sterilization of traditional Chinese medicine mainly focuses on irradiation, microwave, preparation process, active ingredients, drying, fingerprint, etc. The advantages and disadvantages of different sterilization technologies and their suitable scopes, combined with the future development trend in TCM sterilization, were comprehensively discussed for in-depth analysis, to provide a reference for researchers in selecting appropriate sterilization methods. To further promote the scientific development of TCM sterilization, the authors propose that TCM sterilization should be closely combined with technology, equipment, and policy in the future to facilitate rapid modernization of TCM.关键词：Traditional Chinese medicine;Sterilization;CiteSpace;VOSviewer;Knowledge map157|195|1更新时间：2025-02-28
- “据最新研究报道，接触辉光放电等离子体能有效杀灭雅致放射毛霉，为真菌感染治疗提供新思路。”摘要：Mucormycosis infected by Actinomucor elegans is relatively serious in the population, so it is urgent need to inactivate Actinomucor elegans. In order to investigate the sterilization effect and mechanisms of contact glow discharge plasma (CGDP) on Actinomucor elegans, the effects of voltage, time and electrolyte on sterilization efficiency were investigated, and the sterilization conditions were confirmed. The sterilization mechanism of CGDP on Actinomucor elegans was explored by analyzing the changes of colony morphology, spore content leakage and peroxidation damage that induced by CGDP treatment. The results showed that CGDP had remarkable sterilization effects on Actinomucor elegans, under the conditions of 560 V, 15 min and Na2SO4 solution, the sterilization rate (η) was up to 90.71%, the colony diameter, spore germination rate and mycelial biomass accumulation all decreased significantly after CGDP treatment, while leakage of intracellular components and degree of peroxidation damage increased, and spore surface became shrinking and rupturing. It was concluded that the Actinomucor elegans was inactivated due to cell membrane integrity destroying induced by CGDP. The results of this paper could provide a reference for the application and mechanism research of CGDP in the field of fungicidal.关键词：Contact glow discharge plasma;Actinomucor elegans;Sterilization efficiency;Cell membrane integrity117|79|1更新时间：2025-02-28
RADIATION TECHNOLOGY APPLICATION
- “在核辐射环境下，专家改进A*算法，降低核辐射剂量52.11%~55.29%，提升路径规划效果。”摘要：In order to enhance the path planning application of the transfer robot in a nuclear radiation environment, this paper addresses the problem of lack of influence from the surrounding environment on the path by the traditional A* algorithm, and introduces the idea of an artificial potential field in the nuclear radiation environment to improve the evaluation function of this algorithm. This was achieved by obtaining the sum of the radiation source repulsion function, obstacle repulsion function, and target point gravitational force function to calculate the combined force received in the grid, thereby ensuring that the planned path is far from the surrounding environment. For the improved A* algorithm, the MATLAB simulation experiments showed a decrease in the nuclear radiation dose by 52.11%~55.29% compared with the traditional A* algorithm, and a decrease in the number of search nodes by 34.67%~46.19% compared with other improved algorithms. Moreover, the safety distance with the radiation sources and surrounding obstacles was constantly maintained, providing a better implementation effect and allowing the verification of the effectiveness and superiority of the improved A* algorithm.关键词：Transit robot;Nuclear radiation environment;Artificial potential field;A* algorithm;Path planning139|167|2更新时间：2025-02-28
RADIATION PROTECTION
- “在工业辐照领域，专家利用GEANT4软件建立了电子加速器模型，开发了辐照工艺界面软件，为产品辐照工艺设计提供有力工具。”摘要：A mathematical model of a 10 MeV industrial electron accelerator was established by using GEANT4 Monte Carlo software package, and the dose distribution of homogeneous products under different densities were obtained by simulation calculation. Combined with the Qt interface design and development platform, the calculated data were designed by C++ programming. The dose distribution and dose uniformity ratio of different product densities and thicknesses were obtained. In addition, Qt was used to interface the product irradiation dose and the conveyor device transmission speed calculation, daily process management, and dose field distribution data drawing, forming the irradiation process interface software. The accuracy of GEANT4 simulation calculation results and process software was verified by using dose distribution tests and industry research results. The experimental results revealed that the calculation results and test results are in good agreement. The irradiation technology interface software, which can be applied to calculate the irradiation effect and transmission speed of products and other main process parameters in real time, is a useful tool for product irradiation technology design.关键词：Geant4;Mathematical model;Qt;C++ programming;Interface software283|349|0更新时间：2025-02-28
- “在核设施生物剂量研究领域，专家建立了蒙古束颈蝗剂量学模型，精确度高、误差小，为干旱地区核设施生物剂量研究提供解决方案。”摘要：To study the representative dose coefficients near nuclear facilities in the arid regions of Northwest China, a simplified anatomical model of Sphingonotus insects using computed tomography (CT) scanning is proposed. In addition, a voxel model created by using Photoshop and Python is used to assess the results of the simplified anatomical model. The dose coefficients of internal and external 90Sr and 137Cs irradiation on different organs of Sphingonotus insects in the environmental medium are calculated. To verify the feasibility of the proposed model, the results are compared with the dose coefficients reported in the International Commission on Radiological Protection (ICRP) Publication 108. Based on the simplified model adopted by ICRP to arrive at the results reported in Publication 108, the average value of dose coefficients of each organ of the insect is used to calculate the results presented in this paper. The dose coefficients of internal and external 90Sr irradiation for the simplified anatomical model of Sphingonotus were found to be 6.59×10-4 μGyh-1/Bqkg-1 and 6.74×10-4 μGyh-1/Bqkg-1, respectively. Meanwhile, the dose coefficients of internal and external 137Cs irradiation for the simplified anatomical model were 1.34×10-4 μGyh-1/Bqkg-1 and 4.40×10-3 μGyh-1/Bqkg-1, respectively. The dose coefficients were 7.87×10-4μGyh-1/Bqkg-1 and 6.74×10-4μGyh-1/Bqkg-1, respectively. The dose coefficients were 1.33×10-4μGyh-1/Bqkg-1 and 3.51×10-3μGyh-1/Bqkg-1, respectively. The dose coefficients of internal and external 90Sr radiation for reference insects as reported in the ICRP Publication 108 were 1.00×10-2 μGyh-1/Bqkg-1 and 3.90×10-10 μGyh-1/Bqkg-1, respectively. Moreover, the dose coefficients of internal and external 137Cs radiation in the ICRP Publication 108 were 3.20×10-3 μGyh-1/Bqkg-1 and 2.80×10-3 μGyh-1/Bqkg-1, respectively. The above data indicate that the dose coefficients of internal irradiation reported in the ICRP Publication 108 are larger than those calculated using the proposed dosiological model, whereas those of external irradiation in ICRP Publication 108 are smaller. This trend is probably related to the size of the organism, decay rate, and energy of radionuclides. The adoption of a simplified anatomical model, morphologically similar to the organism, and a voxel model, highly overlapping with the organism, in this study allows a visualization of the real exposure situation for the organism considered with high accuracy, proving the feasibility of the insect dosimetry model established in this study.关键词：Sphingonotus insects;Simplified anatomical models;Voxel model;Dose coefficients131|76|0更新时间：2025-02-28
RADIATION INTERDISCIPLINARY RESEARCH
- “北京机械工业自动化研究所研发新型电子直线加速器，应用于无损检测和航空领域，提供整体解决方案。”摘要：The S-band electron linear accelerator developed for nondestructive testing is primarily used to inspect pressure vessels, petrochemical parts, and other industrial components. The X-band electron linear accelerator has been developed in RIAMB, owing to its advantageous flexibility and light weight and can be used for on-site testing. The integral solution of the irradiation electron linear accelerator system provided by RIAMB includes an accelerator, transmission line, production management system, automatic storage and retrieval system, and workshop. The electrocurtain accelerator is currently being developed in RIAMB. At present, it includes two models, with maximum accelerating voltages of 200 kV and 150 kV, respectively. The ion beam surface processing technology includes ion implantation surface modifications, magnetic filtration multi-arc ion coatings, and ion beam assisted deposition coatings. It forms a corrosion-resistant, friction-resistant, anti-icing, and friction-reducing film on the surface of parts such as bearings and pitot tubes, which are primarily used in the aerospace field.关键词：Electron linear accelerator;Nondestructive testing (NDT);Radiation processing;Electrocurtain accelerator;Surface treatment with ion beam159|306|0更新时间：2025-02-28
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