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51.
Boshi Tian Shaohua Liu Chenghao Yu Shikai Liu Shuming Dong Lili Feng Narisu Hu Piaoping Yang 《Advanced functional materials》2023,33(25):2300818
As a less O2-dependent photodynamic therapy (PDT), type I PDT is an effective approach to overcome the hypoxia-induced low efficiency against solid tumors. However, the commonly used metal-involved agents suffer from the long-term biosafety concern. Herein, a metal-free type I photosensitizer, N-doped carbon dots/mesoporous silica nanoparticles (NCDs/MSN, ≈40 nm) nanohybrid with peroxidase (POD)-like activity for synergistic PDT and enzyme-activity treatment, is developed on gram scale via a facile one-pot strategy through mixing carbon source and silica precursor with the assistance of template. Benefiting from the narrow bandgap (1.92 eV) and good charge separation capacity of NCDs/MSN, upon 640 nm light irradiation, the excited electrons in the conduction band can effectively generate O2•− by reduction of dissolved O2 via a one-electron transfer process even under hypoxic conditions, inducing apoptosis of tumor cells. Moreover, the photoinduced O2•− can partially transform into more toxic •OH through a two-electron reduction. Moreover, the POD-like activity of NCDs/MSN can catalyze the endogenous H2O2 to •OH in the tumor microenvironment, further synergistically ablating 4T1 tumor cells. Therefore, a mass production way to synthesize a novel metal-free type I photosensitizer with enzyme-mimic activity for synergistic treatment of hypoxic tumors is provided, which exhibits promising clinical translation prospects. 相似文献
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《材料科学技术学报》2019,35(10):2345-2356
The corrosion kinetics and patina (corrosion products) layer evolution of galvanized steel submitted to wet/dry cyclic corrosion test in a simulated coastal-industrial atmosphere was investigated. The results show that zinc coating has a greater corrosion rate during the initial period and a lower corrosion rate during the subsequent period, and the patina composition and structure can greatly affect the corrosion kinetics evolution of zinc coating. Moreover, Zn5(OH)6(CO3)2 and Zn4(OH)6SO4 are identified as the main stable composition and exhibit an increasing relative amount; while Zn12(OH)15Cl3(SO4)3 cannot stably exist and diminish in the patina layer as the corrosion develops. 相似文献
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《材料科学技术学报》2019,35(10):2144-2155
Ni-Cu nano-coatings were prepared by pulsed electroplating technique in the baths containing various amount of boric acid. Their microstructure, morphologies and corrosion resistance were characterized in detail. The addition of boric acid strongly influences on the microstructure of the Ni-Cu coatings. The coating with a grain size of 130 nm, obtained from the bath containing 35 g L−1 boric acid, shows the highest corrosion resistance. This is attributed to the low-valence Cu ion (Cu+) additions in nickel oxide, which could significantly decrease the oxygen ion vacancy density in the passive film to form a more compact passive film. The higher Cu+ additions and the lower diffusivity of point defects (D0) are responsible for the formation of more compact passive film on the coating obtained from the bath with 35 g L−1 boric acid. 相似文献
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Wang Yicun Shi Hongxi Dong Shuai Li Yan Wang Meng Huai Yanyan Zhang Xintong Chen Xi Mao Chuanbin Gao Xiang Wang Li 《Nano Research》2018,11(4):2248-2255
Nano Research - Candida albicans (C. albicans) infection has a high mortality rate in immunocompromised patients. Owing to the inefficiency of the current diagnostic system and the absence of... 相似文献
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数字媒体艺术专业实践教学体系建设 总被引:1,自引:0,他引:1
针对数字媒体艺术教学体系存在的问题,在阐述数字媒体艺术特点的基础上,分析数字媒体艺术与市场对接不协调的发展现状。结合哈尔滨师范大学传媒学院实践经验和取得的成果,提出数字媒体艺术专业实践教学体系构建的设想。 相似文献
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针对目前"数字逻辑"课程教学中存在的问题,在分析"数字逻辑"课程的特点、教学现状和PBL教学模式内涵的基础上,文章提出将PBL教学方法应用于"数字逻辑"教学过程中的观点,并提出"2+2"教学方案。教学实践表明,将PBL教学模式应用于数字逻辑课程中,提高了学生学习的积极性和主动性,使他们进一步加深了对数字逻辑的原理、知识、概念的理解,为后续课程的学习奠定了坚实的基础。 相似文献
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