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层状锑磷酸嵌接式卟啉锰制备与模拟细胞色素氧化催化研究 总被引:1,自引:0,他引:1
层状锑磷酸嵌接式卟啉锰制备与模拟细胞色素氧化催化研究胡希明,皮宗新,梅治乾,古国榜,黄仲涛(华南理工大学应用化学系,华南理工大学化学工程系,广州,510641)关键词卟啉锰,层状锑磷酸,嵌接,催化性能细胞色素P450是一种含血红素的单充氧化酶,在室温... 相似文献
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Xi-Ming Luo Shuo Huang Peng Luo Kai Ma Zhao-Yang Wang Xi-Yan Dong Shuang-Quan Zang 《Chemical science》2022,13(37):11110
Nanoclusters (NCs) are considered as initial states of condensed matter, and unveiling their formation mechanism is of great importance for directional synthesis of nanomaterials. Here, we initiate the reaction of Ag(i) ions under weak reducing conditions. The prolonged reaction period provides a unique opportunity for revealing the five stages of the growth mechanism of 20-electron superatomic Ag70 NCs by a time-dependent mass technique, that is, aggregate (I) → reduction (II) → decomposition and recombination (III) → fusion (IV) → surface recombination and motif enrichment (V), which is different from the formation process applicable to the gold clusters. More importantly, the key intermediates, Ag14 without free electrons (0e) in the first (stage I) and Ag24 (4e) in the second (stage II), were crystallized and structurally resolved, and the later transformation rate towards Ag70 was further controlled by modulating solvents for easy identification of more intermediates. In a word, we establish a reasonable path of gradual expansion in size and electrons from Ag(i) ions to medium-sized 20e Ag70. This work provides new insights into the formation and evolution of silver NCs, and unveils the corresponding optical properties along with the process.The bottom-up synthesis of “medium-sized” Ag70 (20e) was controlled and tracked, and then revealed. The crystallized key intermediates of Ag14 (0e) and Ag24 (4e) present the growth snapshots of silver nanoclusters. 相似文献
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The key intermediate (2S, 3R)-2-citronellyl-6-methylene-heptan-2,3,7-triol (8) of analogues of zoapatanol was synthesized in seven steps from the chiral synthon 2. The absolute configuration of the new chiral centre in compounds 5a-8 was identified as S by Mukaiyama's method. 相似文献
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Abstract:We study the spectrum of single-photon emission and scattering in a mixed optomechanical model which consists of both linear and quadratic optomechanical interactions. The spectra are calculated based on the exact long-time solutions of the single-photon emission and scattering processes in this system. We find that there exist some phonon sideband peaks in the spectra and there are some sub peaks around the phonon sideband peaks under proper parameter conditions. The correspondence between the spectral features and the optomechanical interactions is confirmed, and the optomechanical coupling strengths can be inferred by analyzing the resonance peaks and dips in the spectra. 相似文献
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Ai-Zheng Chen Yun-Qing Kang Xi-Ming Pu Guang-Fu Yin Yi Li Jun-Yan Hu 《Journal of colloid and interface science》2009,330(2):317-322
The Fe3O4-poly(l-lactide) (Fe3O4-PLLA) magnetic microparticles were successfully prepared in a process of solution-enhanced dispersion by supercritical CO2 (SEDS), and their morphology, particle size, magnetic mass content, surface atom distribution and magnetic properties were characterized. Indomethacin (Indo) was used as a drug model to produce drug-polymer magnetic composite microparticles. The resulting Fe3O4-PLLA microparticles with mean size of 803 nm had good magnetic property and a saturation magnetization of 24.99 emu/g. The X-ray photoelectron spectroscopy (XPS) test indicated that most of the Fe3O4 were encapsulated by PLLA, which indicated that the Fe3O4-PLLA magnetic microparticles had a core–shell structure. After further loading with drug, the Indo-Fe3O4-PLLA microparticles had a bigger mean size of 901 nm, and the Fourier transform infrared spectrometer (FTIR) analysis demonstrated that the SEDS process was a typical physical coating process to produce drug-polymer magnetic composite microparticles, which is favorable for drugs since there is no change in chemistry. The in vitro cytotoxicity test showed that the Fe3O4-PLLA magnetic microparticles had no cytotoxicity and were biocompatible, which means there is potential for biomedical application. 相似文献
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