最新刊期
卷 37 ， 期 5 ， 2019
- “核酸自组装合成框架核酸，广泛应用于多个领域，专家综述了其构建及成像技术，为研究提供新方向。”摘要：Nucleic acids are biomolecules that are carriers of genetic information using which several micro and macro structures are constructed. Framework nucleic acids (FNAs), which are synthesized via nucleic acid self-assembly and widely used in chemistry, biomedicine, radiation biochemistry, and other fields, are novel nanostructures designed and controlled at the nanoscale. Imaging technologies play a crucial role in intuitively visualizing the structure and function of FNAs. Here, the structure and imaging technology for FNAs are reviewed, and the application of FNAs in biochemical detection, especially detection of ionizing radiation, and their developmental prospects are summarized.关键词：Framework nucleic acids;DNA nanotechnology;DNA origami;Imaging technology;Biochemical detection51|90|2更新时间：2025-02-28
REVIEW
- “在材料科学领域，研究人员采用三烯丙基异氰脲酸酯作为交联剂，与无规共聚聚丙烯共混制备片材，通过γ射线辐照和超临界二氧化碳发泡，研究了交联剂和吸收剂量对聚丙烯结构和发泡性能的影响。”摘要：Polypropylene random copolymer (PPR) was mixed with triallyl isocyanurate (TAIC) and pressed into a sheet. PPR sheets were irradiated by γ-rays and then foamed by supercritical carbon dioxide. The effects of TAIC and absorbed dose on the structure and foaming ability of PPR were evaluated by the gel fraction test and by determining the crystallization behavior and foam cellular structure. It was found that PPR was cross-linked by TAIC. After irradiation, the degree of crosslinking in PPR/TAIC(2%) increased, and the degree of oxidative degradation increased with absorbed dose. α and γ crystals were observed in PPR, and more γ crystals were found after crosslinking. The γ crystals induced more nucleation sites and formed better foams. The optimal absorbed dose obtained in this study was 25 kGy. The cell diameter decreased to 41 μm and the cell density increased to 1.5 × 1010 cm-3. The tensile strain of the sample reached 230%, and the suitable foaming temperature window reached 10 ℃ at the release pressure of 20 MPa.关键词：Polypropylene random copolymer (PPR);Radiation crosslinking;γ-crystal;Crystallinity;Supercritical carbon dioxide foaming47|35|1更新时间：2025-02-28
- “在材料科学领域，研究人员通过真空辅助自组装和电子束辐照技术，成功制备了自支撑氧化石墨烯复合膜，显著提高了耐静水压性能和酸回收效率。”摘要：A freestanding graphene oxide (GO) composite membrane was prepared by combining vacuum-assisted self-assembly with electron-beam irradiation. 1-Allyl-3-vinylimidazolium chloride ([AVIM]Cl) was chosen to complex and conjugate with the GO sheets. Fourier-transform infrared spectra demonstrated the success of the covalent bonding between [AVIM]Cl and the GO sheets. The results of hydrostatic pressure resistance test showed that the resistance of hydrostatic pressure was noticeably increased by introducing [AVIM]Cl. After further treatment by electron-beam irradiation, the obtained composite membrane can even withstand a hydrostatic pressure of 10.8 kPa. X-ray diffraction patterns illustrated that the imidazolium-based ionic liquid can effectively limit the swelling of the composite membrane in aqueous condition and reduce interlayer spacing change of the composite membrane under dry and wet conditions and that the interlayer spacing change was further reduced after irradiating the composite membrane with the electron-beam. The reverse salt rate of the composite membrane was as low as 0.14 mol/(m2∙h), which meets the requirement of a forward osmosis membrane. In this study, application of the forward osmosis process in acid recovery was investigated by using the irradiated composite membrane as a barrier and salt water as a permeation solution. The 10 h test results indicated that the H+ permeation coefficient of the irradiated composite membrane can reach 87.9 m/h, which is three orders of magnitude higher than that of the conventional diffusion dialysis method.关键词：Electron-beam irradiation;Graphene oxide;Ionic liquid;Forward osmosis;Acid recovery38|36|0更新时间：2025-02-28
- “最新研究发现，中空介孔二氧化硅微球表面接枝pH响应性聚合物，负载缓蚀剂BTA，具有优异的防腐蚀性能。”摘要：In this work, grafting polymerization of dimethylaminoethyl methacrylate was induced by γ-ray radiation on hollow mesoporous silica microspheres of diameter 230 nm, which were prepared using a hard-template method. The prepared microspheres have a uniform cavity structure and controllable pore size (3~10 nm). Benzotriazole (BTA) was loaded by vacuum perfusion into the polydimethylaminoethyl-methacrylate-coated hollow mesoporous silica microspheres. The load capacity of BTA was as high as 22.8% (mass fraction). The pH-responsive release behavior of BTA from the microspheres in aqueous solutions with different pH values was investigated. The cumulative release amount in acidic solution was higher than those in basic and neutral solutions. The BTA-loaded microspheres can be mixed homogenously with a waterborne polyurethane coating. The electrochemical experiments showed that the composite coating has an excellent anti-corrosion property on the Cu electrode. The results indicate that hollow mesoporous silica microspheres modified by the radiation-grafting method have application prospects in the field of anti-corrosive metal coatings.关键词：Radiation grafting;Hollow-mesoporous silica microspheres;pH responsive;Benzotriazole;Anti-corrosive coating34|57|0更新时间：2025-02-28
RADIATION CHEMISTRY
- “秀珍菇无细胞滤液合成的胶体银纳米粒子具有优良的抗菌活性和广谱抗菌活性，为抗菌材料研究提供新方向。”摘要：This study evaluated the in vitro antibacterial activity of silver nanoparticles (AgNPs) synthesized from the cell-free filtrate of Pleurotus geesteranus. AgNPs were characterized by ultraviolet-visible absorption spectroscopy, X-ray diffraction, transmission electron microscopy, and zeta potential. The antibacterial activity of the AgNPs was evaluated by the agar diffusion method against Vibrio anguillaru, Vibrio alginolyticus, Escherichia coli, Staphylococcus aureus, Bacillus subtilis, and Pseudomonas aeruginosa. Escherichia coli was selected as the index bacteria to determine the minimum inhibitory concentration (MIC) and the minimum bactericidal concentration (MBC) of the AgNPs. Well-dispersed spherical or nearly spherical AgNPs were obtained with particle sizes ranging from 4.5 to 18.2 nm. The acquired AgNPs effectively inhibited the growth of various bacteria. The MIC and MBC were 8.2 μg/mL and 32.5 μg/mL, respectively. The controllable synthesis of AgNPs achieved using the cell-free filtrate of P. geesteranus produced AgNPs that exhibited excellent broad-spectrum antibacterial activity.关键词：Silver nanoparticles;Biosynthesis;Pleurotus geesteranus;Antibacterial activity25|48|0更新时间：2025-02-28
RADIOBIOLOGY AND RADIOMEDICINE
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Breeding of tacrolimus high-producing strains by gamma-ray radiation and nitrosoguanidine mutagent AI导读
“在生物发酵领域，研究人员采用60Co γ射线辐射和NTG复合诱变技术，成功选育出高产他克莫司菌株FIM-17-17，发酵水平显著提高。”摘要：To enhance the tacrolimus fermentation titer of the production strain, original strains were treated using 60Co γ-ray radiation at a dose of 450 Gy and nitrosoguanidine mutagen (NTG) at a concentration of 3 mg/mL for 30 min when combined with a streptomycin and gentamycin resistance screening technique. A mutant strain named FIM-17-17 showed a 65% higher-yield tacrolimus than that of the original strain in a flask culture. The stability of the high-yield mutants and the effects of different resins (AB-8, D101, HT60, XAD16, HP20, and XDA-8) on the tacrolimus fermentation titer were investigated, and the optimized conditions of the mutant strain were tested in a 1-ton fermentation tank. The mutant strain FIM-17-17 showed high genetic stability. When 2% D101 resin was added to the culture medium, the tacrolimus titer increased by 29.8%, and the production of tacrolimus reached 1 319 μg/mL in the 1-ton fermentor. These results indicate that a tacrolimus high-producing strain can be obtained efficiently by compounding mutagenesis of 60Co γ-ray radiation and NTG.关键词：Streptomyces;Tacrolimus;Fermentation;Radiation mutagenesis;Nitrosoguanidine mutagen(NTG)37|26|1更新时间：2025-02-28
RADIATION TECHNOLOGY APPLICATION
- “据最新研究，电动汽车低频电流电磁暴露对司乘人员安全无影响，为电磁安全研究提供新见解。”摘要：To study the safety of passengers in the cabin of an electric vehicle, the electromagnetic exposure produced by the low frequency current in the vehicle’s power cable was modeled. The low frequency current was used as the excitation source, and the magnetic induction intensity, induction current density, and induction electric field intensity in the trunk and central nervous system of the driver and co-driver were calculated and analyzed using the Comsol Multiphysics finite element software. The results showed that the maximum values of magnetic induction intensity in the central nervous system were concentrated in the scalp area. The maximum induction intensity values were 0.073×10-2 μT and 0.055×10-2 μT in the driver and co-driver’s seats, respectively. The maximum induced current densities were mainly concentrated in the brain tissues, being 11.3 μA/m2 and 0.616 μA/m2 in the driver and co-driver’s seats, respectively. Similarly, the maximum induced electric field values were also mainly concentrated in the brain tissues, reaching 0.426 mV/m and 0.013×10-2 mV/m in the driver and co-driver’s seats, respectively. In addition, from the distribution trend of the induction field, the lower the distance to the power cable is, the larger is the value of the induction field; conversely, the greater the distance, the weaker is the induction field. In conclusion, comparing the maximum induction field value with the ICNIRP standard and national standard GB8702-2014, the maximum values of the induction field in the central nervous system and trunk were found to be much smaller than the maximum exposure limit stipulated by the standards. Therefore, the electromagnetic exposure in this low frequency electromagnetic environment is within a safe range.关键词：Electric vehicle;Low frequency electromagnetic field;Electromagnetic exposure;Human model;Safety assessment43|47|1更新时间：2025-02-28
RADIATION PROTECTION
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