最新刊期
卷 39 ， 期 5 ， 2021
- “In the history of sciences, the solvated electron concept, where an electron is isolated in a liquid with polarized molecules, has emerged as a groundbreaking development. Expert xx explored the solvated electron topic, which provides a new vision of old results and opens up a new direction for research.”摘要：The history of sciences is rich in founding experiments, which have given rise to such developments that they constituted full-fledged disciplines. Much more rarely, knowledge coming from very distant horizons converged at a moment to offer a very new vision of old results and to provoke an explosion of new research. This was the case for the solvated electron. But where does such a concept come from, of an electron isolated in a liquid whose molecules are polarized by its charge?关键词：Solvated electron;Properties;Structure models;Metal-ammonia solutions;Radiation chemistry277|189|0更新时间：2025-03-01
- “自由基光聚合技术在表面薄层固化领域广泛应用，但厚膜固化存在技术难题。专家综述了光诱导暗聚合体系的研究进展，为解决厚膜固化问题提供新思路。”摘要：Free radical photopolymerization is an environmentally friendly green production and processing technology and is widely used in the curing of thin samples such as coatings, adhesives, and varnishes. However, for thicker samples or opaque materials, limited light absorption and scattering and reflection from the components of the formulation lead to the failure of polymerization. Dark polymerization is an effective strategy that overcomes these limitations. This paper reviews current developments in the field of photoinduced dark radical polymerization in terms of features of the dark polymerization formulation, developed photoinitiator/initiating systems and active monomers with dark polymerization, and application scope and trends.关键词：Initiator/initiation system;Free radical photopolymerization;Dark-polymerization110|277|0更新时间：2025-03-01
REVIEW
- “最新研究发现，通过电子束引发预辐射接枝法，将甲基丙烯酸环氧丙酯接枝到聚丙烯无纺布上，并物理包裹磷钼酸铵，制备出负载有磷钼酸铵的聚丙烯接枝物，对铯离子具有高效选择性吸附能力，为放射性核素处理提供新思路。”摘要：Glycidyl methacrylate (GMA) was grafted onto polypropylene (PP) nonwovens by electron-beam-induced pre-irradiation grafting, and ammonium phosphomolybdate (AMP) was physically loaded on the grafted polymer to prepare a composite material called PP-g-GMA@AMP. The loading rate of AMP was 5.72%, and the grafting rate of GMA was 32.41%. The maximum adsorption efficiency of Cs(I) by PP-g-GMA@AMP was 97.23% at pH=6. The adsorption kinetic behavior was in accordance with pseudo-second-order kinetic equation. The experimental results showed that the adsorption process using PP-g-GMA@AMP conforms to Langmuir adsorption model and the theoretical maximum adsorption capacity was 2.59 mg/g. PP-g-GMA@AMP showed good reusability and the adsorption capacity was reduced by only 9.91% after three repeated uses. PP-g-GMA@AMP showed excellent selective adsorption ability for Cs(I) in the presence of Na(I), Mg(II), and Ca(II). The distribution coefficient of Cs(I) on AMP was 120.45, while those of Na(I), Mg(II), and Ca(II) were 2.71, 1.23, and 1.84, respectively. According to the difference in partition coefficients, Cs(I) was separated from Na(I), Mg(II), and Ca(II) by dynamic column chromatography using a 0.5 mol/L NH4Cl eluent solution, and the Cs(I) effluent liquid was concentrated to one-fifth the volume of the injection solution.关键词：PP nonwovens;Ammonium phosphomolybdate (AMP);Pre-irradiation grafting;Cs(I);Selective adsorption160|225|0更新时间：2025-03-01
- “在食品科学领域，研究人员采用60Co γ射线辐照结合溶剂法提取花生茎叶酚酸，优化工艺参数后，酚酸含量显著提高，抗氧化活性增强。”摘要：Arachis hypogaea L. stems and leaves (AHSL) were used as raw materials, to extract phenolic acids through 60Co γ irradiation and solvent synergistic method. The extraction conditions were optimized by the response surface methodology of Box-Behnken, following a separation; thereafter, the antioxidant activity of the phenolic acid AHSL was studied. The results showed that the optimal extraction process could be achieved at an absorbed dose of 6.70 kGy and 70% ethanol concentration with 27∶1 liquid-solid ratio (mL∶g). The highest AHSL phenolic acid yield was (2.25±0.11)%. Among the process parameters, the absorbed dose showed the most significant effect on the AHSL phenolic acid yield (p=0.000 1).The phenolic acid content increased to 1.80 fold after extraction and purification with chloroform and ethyl acetate. Concerning the antioxidant activity, AHSL phenolic acid showed better free radical scavenging ability and ferric-reducing power than the ethanol extracts. Moreover, no significant difference could be observed in the hydroxyl radical scavenging effect between AHSL phenolic acid and tea polyphenols under the same concentration (p˃0.05). More than 50% of DPPH free radicals and hydroxyl free radicals could be removed at the AHSL phenolic acid concentration of 100 μg/mL. The results revealed that 60Co γ ray irradiation combined with ethanol extraction is feasible, and the phenolic acid from AHSL has strong antioxidant activity in vitro.关键词：Arachis hypogaea L. stems and leaves;Phenolic acid;Extraction;Antioxidant activities118|149|0更新时间：2025-03-01
- “在医用防护服领域，专家研究了不同材质防护服辐照灭菌后性能变化，为防护服辐照灭菌提供科学依据。”摘要：The post-radiation effect of three kinds of disposable medical protective clothing made of polyethylene terephthalate/polyurethane (PET/PU), polypropylene/polyethylene (PP/PE), and polyethylene (PE) after radiation sterilization and the effects of radiation on the properties of protective clothing were investigated. The changes in surface morphology, hydrophilicity, mechanical properties, and free radicals of medical protective clothing materials after radiation sterilization were systematically studied using scanning electron microscopy (SEM) and electron spin resonance (ESR) spectroscopy, and by examining the surface contact angle and tensile properties at break. The results showed that the surface morphology of protective clothing made of PET/PU, PP/PE, and PE undergoes no obvious change after γ-ray irradiation. However, the hydrophobicity of the surfaces—whose contact angles were reduced by 2.8%, 7.9%, and 17.8%, respectively—decreased. γ-ray irradiation has little effect on the tensile properties of PET/PU at the sterilizing dose (≤ 50 kGy). On the other hand, the tensile breaking strength and elongation at break of PP/PE and PE protective clothing decreased with the increasing absorbed doses. The signal intensity of free radicals produced by PP/PE and PE protective clothing increased with the absorbed dose and the concentration of free radicals decreased rapidly with the storage time and tended to stabilize after one month.关键词：Disposable medical protective clothing;Radiation sterilization;Mechanical properties;Free radicals150|351|0更新时间：2025-03-01
RADIATION CHEMISTRY
- “最新研究发现，氯马斯汀能促进大鼠髓鞘形成，抑制少突胶质前体细胞增殖，为神经损伤修复提供新策略。”摘要：A rat radiation injury model was constructed, in which myelin basic protein (MBP) expression was detected via western blot. Primary oligodendrocyte precursor cells (OPCs) and neuronal cells were isolated from Sprague-Dawley rats, and expression of neurofilament protein and chondroitin sulphate proteoglycan was detected via immunofluorescence to identify isolated primary cells. Cell counting kit-8 (CCK8) experiments were used to assess the effects of different concentrations of clemastine on OPC proliferation. Five groups of lentiviral shRNA vector targeting muscarinic receptor were constructed, and their transfection efficiencies were quantified using RT-qPCR and western blot. To explore the effect of clemastine on OPC differentiation and myelination, MBP and OLIG2 expression were detected via immunofluorescence and western blot. Clemastine was found to promote MBP formation in rats and inhibit OPC proliferation in a concentration-dependent manner. Compared with the control group, CHRM1, CHRM2, CHRM3, CHRM4, and CHRM5 shRNA expression significantly decreased mRNA and protein expression levels (p<0.01). Among these, CHRM2 displayed the best interference efficiency.CHRM2 interference (M2R) significantly increased MBP and OLIG2 expression in a manner that was further enhanced by clemastine treatment (p<0.05). Clemastine enhances the antimuscarinic effect, promotes the differentiation of OPCs into OLs, and plays an important role in myelination by up-regulating the expression of MBP.关键词：Clemastine;Cell differentiation;Myelination;Oligodendrocyte precursor cells138|154|0更新时间：2025-03-01
- “最新研究发现，过表达Daxx蛋白能增强γ射线照射诱导的细胞凋亡，为辐射防护提供新思路。”摘要：We studied the effects of overexpression of deathdomainassociated protein (Daxx) on cell apoptosis under γ-ray radiation. Further, we explored the relationship between Daxx and radiation-induced apoptosis and investigated the mechanism behind such apoptosis. Through transfection, cervicalcancer HeLa cells were divided into a control group, an empty plasmid-transfected negative group, and a Daxx-transfected group; the HeLa cells were irradiated with different doses of γ-rays using a cell irradiator. The expression of Daxx protein in cells was detected by Western blot. Cell proliferation was detected by MTT. The relative activity of caspase-8 in cells was detected by ELISA whereas the cell apoptosis was detected by flow cytometry. The results showed that the total number of cells decreased with the increase in absorbed dose, whereas the number of deformed cells increased. Furthermore, the degree of Daxx expression increased with the increase in absorbed dose. Comparing the cells of the Daxx-transfected group with those of the unirradiated control group, we observed statistically significant increments (p<0.01, p<0.05, p<0.05) in the rate of inhibition against cell proliferation, the A405 value, and rate of apoptosis. Hence, overexpression of Daxx promotes radiation-induced apoptosis by upregulating caspase-8 activity in the γ-ray irradiated cells.关键词：Deathdomainassociated protein (Daxx), Apoptosis, Ionizing radiation CLC;R811103|248|0更新时间：2025-03-01
- “在电磁辐射领域，研究了双波源交替入射对大鼠SAR的影响，发现交替时间间隔增加导致SAR非线性升高，为电磁辐射研究提供新方向。”摘要：In this study, the whole-body specific absorption rate (SARw) and tissue average specific absorption rate (SARa) of rats under alternatively incident microwave exposure (1.5 GHz and 9.4 GHz) were calculated by finite-difference time-domain (FDTD). The effects of combined and alternating microwave exposures on the SARw and SARa values of rats were discussed and compared with those of single frequency irradiation. Numerical simulation of electromagnetic exposure revealed that under double-source alternating irradiation, both SARw and SARa values of rats were affected by the combined incidences. With the increment in the duration of alternating exposure, both SARw and SARa tended to increase nonlinearly. On comparison with SARw and SARa values obtained from single frequency irradiation, it was found that the SARw value of double-source alternating irradiation was limited within the two SARw values that were determined by two individual irradiation frequencies, corresponding to 1.5 GHz and 9.4 GHz. However, the SARa value of testis tissues that back-incident short-axis polarization of double-source alternating irradiation is 31.2% higher than the maximum SARa value of the two wave sources acting alone. The SARa value (1.5 GHz, long-axis polarization; 9.4 GHz, short-axis polarization) of the spleen is 18.9% higher than the maximum SARa value of the single-wave source when the double-source is incident back.关键词：Composite electromagnetic field;Finite difference time-domain;Electromagnetic exposure;Specific absorption rate101|158|1更新时间：2025-03-01
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Effect of air gap under bolus on superficial dose and depth of dose maximum during radiotherapy AI导读
“在放疗领域，研究了Bolus下空腔对浅表肿瘤剂量的影响，发现无Bolus时剂量计算误差大，需加Bolus，且空腔厚度为0毫米最佳。”摘要：To explore the influence of the air gap under bolus on the superficial dose and the maximum dose depth during radiotherapy for superficial tumors. A 30 cm×30 cm×30 cm phantom and an adjacent 10 mm-thick bolus were created in the Eclipse treatment planning system (TPS). The bolus and phantom materials were set as water. The gaps between the bolus and phantom were set as 0 mm, 2 mm, 5 mm, 10 mm, 20 mm, and 30 mm-thick air. The source skin distance was set as 100 cm, while the field sizes were set as 5 cm×5 cm, 10 cm×10 cm, 15 cm×15 cm, 20 cm×20 cm, and 25 cm×25 cm. The dose (Ds) at a depth of 1 mm on the superficial surface and the depth value (dmax) of the maximum dose point in the phantom were obtained under different air gaps and field sizes. A PTW water tank was used to measure the Ds and dmax under the same conditions as the TPS on the Varian Trilogy linear accelerator, the superficial dose Ds was measured with the EBT3 film, and the ionization chamber was used to obtain dmax. The TPS and experimental measurement results were then compared. The results showed that the Ds from the TPS was 0 when there was no bolus, while the dose from the measurement was not 0. The TPS and measurement results showed that when the field size was 5 cm×5 cm, Ds decreased the fastest with the increase in air gap thickness. When the field size was 15 cm×15 cm or above, the change in Ds with the air gap thickness was relatively stable. The TPS and experimental measurement results showed that dmax was the largest without a bolus. The change in dmax in the TPS was relatively stable with an increase in air gap thickness. The experimental results showed that when the field size was 10 cm×10 cm or smaller, dmax changed more significantly as the air gap thickness increased. When the field size was 15 cm×15 cm or larger, dmax remained relatively stable as the air gap thickness increased. The TPS and experimental measurement results showed that the smaller the field size, the larger the dmax, except for large differences in Ds between them when there was no bolus. The differences in Ds of the other field sizes and air gap thicknesses were all close to 0. The overall differences between the TPS and the experimental measurement dmax values were large for different air gap thicknesses. The differences were larger for small field sizes than for large field sizes, and when the air gap thickness was 0 mm, the difference in dmax for all field sizes was the closest to 0. The TPS and experimental measurement results showed that a bolus with an underlying 0-mm air gap is needed during superficial tumor radiotherapy.关键词：Bolus;Air gap;Radiotherapy;Surface dose;Maximum dose depth131|230|0更新时间：2025-03-01
RADIOBIOLOGY AND RADIOMEDICINE
- “在核辐射环境机器人路径优化领域，专家提出了改进平滑A*算法，有效提升了路径平滑性和搜索效率，为核辐射环境下机器人移动路径最优问题提供解决方案。”摘要：To solve the problem concerning the optimal path of robots in nuclear radiation environments, we propose herein an improved smooth A* algorithm to improve the smoothness of the path while satisfying the robot radiation protection requirements. This algorithm comprehensively considers factors, such as the dose rate of the nuclear radiation field, obstacles, path length, and number of inflection points, and the cost of absorbed dose, by introducing obstacle weighting and smoothing optimization; this significantly improves the search efficiency and path quality. A simulation experiment initially shows that when compared with the traditional A* algorithm, the improved A* algorithm without obstacle weighting and smoothing optimization reduces the total dose cost of the path generated by more than 45% under the obstacle-free and obstacle scenes. After introduction of obstacle weighting and smoothing optimization, the search efficiency is increased by 11.8%, and the smoothness is increased by 52.9%. Therefore, the proposed algorithm meets the design requirements.关键词：Nuclear radiation environment;Mobile robot;Path planning;Smooth A* algorithm;Obstacle weighting161|260|3更新时间：2025-03-01
- “据最新研究，高铁沿线弓网电弧电磁环境对公众健康无风险。”摘要：To analyze the amplitude frequency characteristics of the pantograph catenary arc along a high-speed railway line and evaluate the safety of the general public against electromagnetic exposure, field measurements were obtained at distances of 10 m, 20 m, and 30 m (points A, B, and C, respectively) from the center of a high-speed railway line. The distribution of electric field strengths at different distances was obtained by calculating and analyzing the measured data. The results showed that the frequencies of the pantograph catenary arc were mainly distributed in the range of 2~500 MHz, and there were some pulses in the range of 500~1 000 MHz. The frequencies of the maximum electric field strengths at different points were mainly distributed in the range of 12~16 MHz. The maximum electric field strengths at points A, B, and C were 21.8 mV/m, 18.1 mV/m, and 7.89 mV/m, respectively, which are significantly lower than the general public's limit of controlling the electromagnetic environment (GB 8702―2014) issued by the Ministry of Environmental Protection and the General Administration of Quality Supervision, Inspection and Quarantine. This indicates that the general public is safe at distances of 10 m, 20 m, and 30 m from the center of a high-speed railway line.关键词：High-speed railway;Pantograph catenary arc;Amplitude frequency characteristics;Safety evaluation147|177|0更新时间：2025-03-01
RADIATION PROTECTION
- “湖南茯茶中“金花”菌ACF-1被鉴定为冠突曲霉菌，参与茯茶化学成分变化，为揭示茯茶风味品质形成机理提供新依据。”摘要：This study aimed to accurately identify the “golden flower” fungus, and characterize its effects on the chemical composition of Fu tea. A “golden flower” fungus strain was isolated from Hunan Fu tea and named as ACF-1. The ACF-1 was identified as Aspergillus cristatus using culture characteristics, optical microscopic structure, electron microscopic structure, ITS region sequence alignment analysis, and multigene phylogeny analysis based on β-tubulin, calmodulin, and RNA polymerase Ⅱ gene sequences. ACF-1 fungus was inoculated into sterilized primary dark tea for a loose tea “flowering” experiment, to analyze changes in the main chemical components. Polyphenol, free amino acid, soluble sugar, and flavonoid contents changed substantially in the “flowering” samples compared to non-“flowering”, decreasing by 11.3%, 17.3%, 11.9%, and 33.8%, respectively. The variation of chemical components made a foundation for the quality improvement during the process. These findings provide a more comprehensive understanding of the formation of the sensory characteristics in Fu tea and provide a guidance for the development and utilization of “golden flower” fungus.关键词：Aspergillus cristatus;Identification;Polygenic alignment modified;Artificial inoculation;Chemical composition96|223|0更新时间：2025-03-01
- “最新研究显示，国内外香蕉中40K放射性水平对健康影响微小，无需预防措施。”摘要：The aim of this study is to determine the levels of 40K radionuclides in bananas procured from different regions, calculate the annual effective dose, analyze the carcinogenic risk, and establish baseline data. Nine kinds of bananas from 6 regions in China and three kinds of bananas from 2 regions abroad were collected. After peeling, slicing, drying, crushing, sieving, and sample loading, the samples were measured and analyzed using a γ-ray spectrometer. 40K was detected in all bananas, but the concentrations of the other radionuclides were lower than the detection limit. The radioactivity concentration of 40K in Philippine imperial banana was the highest and that in Xigong banana from Guangxi was the lowest. The average 40K radioactivity of imported bananas was (472.1±59.5) Bq/kg, while that of domestic bananas was (361.9±80.7) Bq/kg. There was no significant difference between the two groups (p<0.05). The annual effective dose caused by 40K in Fujian Hongpi banana was the highest (5.4 μSv/a), while that in Xigong banana from Guangxi was the lowest (3.1 μSv/a). The average increased cancer risk due to banana intake was 1.6×10-5. The highest concentration of 40K in the bananas considered in this study was (540.8±26.8) Bq/kg, which is much lower than the national standard limit. The annual effective dose and carcinogenic risk caused by 40K in the bananas are at the normal level, thus eliminating the need for consumers to take any precautions.关键词：Banana;Radionuclide;40K;Annual effective dose;Carcinogenic risk191|223|0更新时间：2025-03-01
RADIATION INTERDISCIPLINARY RESEARCH
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