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Guanglin Huang Shota Hasegawa Dr. Yoshifumi Hashikawa Dr. Yuki Ide Prof. Dr. Takashi Hirose Prof. Dr. Yasujiro Murata 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(2):e202103836
An H2O2 molecule was isolated inside hydroxylated open-cage fullerene derivatives by mixing an H2O2 solution with a precursor molecule followed by reduction of one of carbonyl groups on its orifice. Depending on the reduction site, two structural isomers for H2O2@open-fullerenes were obtained. A high encapsulation ratio of 81 % was attained at low temperature. The structures of the peroxosolvate complexes thus obtained were studied by 1H NMR spectroscopy, X-ray analysis, and DFT calculations, showing strong hydrogen bonding between the encapsulated H2O2 and the hydroxy group located at the center of the orifice. This OH group was found to act as a kinetic stopper, and the formation of the hydrogen bonding caused thermodynamic stabilization of the H2O2 molecule, both of which prevent its escape from the cage. One of the peroxosolvates was isolated by HPLC, affording H2O2@open-fullerene with 100 % encapsulation ratio, likely due to the intramolecular hydrogen-bonding interaction. 相似文献
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Hideo MOHRI Kazuo INABA Sumio ISHIJIMA Shoji A. BABA 《Proceedings of the Japan Academy. Series B, Physical and biological sciences》2012,88(8):397-415
Eukaryotic flagella and cilia have attracted the attention of many researchers over the last century, since they are highly arranged organelles and show sophisticated bending movements. Two important cytoskeletal and motor proteins, tubulin and dynein, were first found and described in flagella and cilia. Half a century has passed since the discovery of these two proteins, and much information has been accumulated on their molecular structures and their roles in the mechanism of microtubule sliding, as well as on the architecture, the mechanism of bending movement and the regulation and signal transduction in flagella and cilia. Historical background and the recent advance in this field are described. 相似文献
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Hideo Sawada Mieko Kikuchi Masakazu Nishida 《Journal of polymer science. Part A, Polymer chemistry》2011,49(5):1070-1078
Fluoroalkyl end‐capped acrylic acid oligomer [RF‐(ACA)n‐RF] reacted with tetraethoxysilane and silica nanoparticles in the presence of low molecular weight aromatic compounds [ Ar‐H ] such as cetylpyridinium chloride (CPC) and bisphenol AF under alkaline conditions to afford RF‐(ACA)n‐RF/SiO2 nanocomposites‐encapsulated Ar‐H in 47–94% isolated yields. These fluorinated silica nanocomposites‐encapsulated Ar‐H can exhibit no weight loss behavior corresponding to the contents of Ar‐H after calcination at 800 °C under atmospheric conditions, although fluoroalkyl end‐capped acrylic acid oligomer in the nanocomposites decomposed completely under similar conditions. UV‐vis spectra of well‐dispersed methanol solutions of RF‐(ACA)n‐RF/SiO2/CPC nanocomposites before calcination show that CPC can be encapsulated into fluorinated silica nanocomposites with encapsulated ratios: 23–43%. The fluorinated nanocomposites after calcination was found to exhibit a higher antibacterial activity related to the presence of CPC in the composites. Encapsulated bisphenol AF into RF‐(ACA)n‐RF/SiO2 nanocomposites before and after calcination at 800 °C can exhibit a good releasing ability toward methanol with released ratios: 48 and 26%, respectively. 1H MAS NMR, HPLC analysis, and LC‐MS spectra of RF‐(ACA)n‐RF/silica nanocomposites‐encapsulated bisphenol AF also showed the presence of bisphenol AF in the nanocomposites even after calcination at 800 °C under atmospheric conditions. These findings suggest that CPC and bisphenol AF can exhibit a nonflammable characteristic in the fluorinated silica nanocomposites. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011 相似文献