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排序方式: 共有419条查询结果,搜索用时 171 毫秒
411.
Y Takemoto T Ueyama H Saito S Horio S Sanada J Shoji S Yahara O Tanaka S Shibata 《Chemical & pharmaceutical bulletin》1984,32(8):3128-3133
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Takanori Suzuki Ryuuichi Tamaki Eisuke Ohta Takashi Takeda Hidetoshi Kawai Kenshu Fujiwara Masako Kato 《Tetrahedron letters》2007,48(22):3823-3827
The spiro-acridan/acridinium-based dynamic redox pair (1/22+) transduces the electrochemical input into UV-vis and fluorescence spectra, whereas the 2,2′-bipyridine units in 1 works as a bidentate ligand for metal ions. X-ray structural analyses of this redox pair and the corresponding Zn-complexes [1-ZnI2/22+-Zn2+(OTf−)4] demonstrate drastic structural changes upon electron-transfer, thus metal binding properties are modified by redox reactions. 相似文献
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Vizuete M Gómez-Escalonilla MJ Fierro JL Yudasaka M Iijima S Vartanian M Iehl J Nierengarten JF Langa F 《Chemical communications (Cambridge, England)》2011,47(48):12771-12773
A soluble hybrid nanomaterial that combines fullerenes and carbon nanohorns (CNHs) has been prepared and fully characterized. Electrochemical investigations revealed that the CNHs modify the electron accepting ability of C(60) in the hybrid material. 相似文献
417.
H. Nakazumi T. Ueyama T. Kitaguchi T. Kitao 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-2):59-66
Abstract The absorption bands of the coumarin, the thiocoumarin and thiochromone have been examined by the PPP calculation with variable β approximation, changing with increasing ring size. The calculated longest-wavelengths (λ1) of these series were in good agreement with the experimental values measured in ethanol. A bathochromic displacement of λ1 produced by annelation of a benzene ring to a 2H-pyran-2-one, a coumarin and its thio analogues might be mainly due to a reduction of LUMO energy levels and/or increase of HOMO energy levels. The substituent effect on absorption spectra in the coumarin, the thiocoumarin and thiochromone series has also been examined, and discussed in terms of PPP calculations. 相似文献
418.
Abstract
Vortex levitation can achieve non-contact handling by blowing air into a vortex cup through a tangential nozzle to generate a swirling flow. In this paper, we focused on the relationship between the sucking pressure and the flow dynamics when gap distance from the cup to a work piece changes. Then simultaneous measurement of a pressure and a flow field in the cup was performed. As a result, the mean pressure changes and the pressure fluctuation inside the cup enhances with increasing gap height. Especially, periodic pressure perturbation is observed with wide gap height and it synchronizes with an eccentric rotation of the swirling flow. It is also found that the rotation axis of swirling flow steadily inclines against the central axis of the cup for appropriate gap height. 相似文献419.