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51.
Adsorption and photochemical behaviors of the novel cationic xanthene derivative on the clay surface
Yuta Ohtani Yohei Ishida Yuka Ando Hiroshi Tachibana Tetsuya Shimada Shinsuke Takagi 《Tetrahedron letters》2014
Novel tetra-cationic xanthene derivative (Flu) was synthesized. Its adsorption and photochemical behaviors on the clay surface were investigated. Fluorescence quantum yield (?f) and fluorescence lifetime were 0.50 and 2.9 ns for Flu/clay complex. ?f of Flu was enough high (>0.1) even at high density conditions (0.080 molecules nm−2). It is supposed that the strong interaction between clay and Flu by the ‘Size-Matching Effect’ realizes the highly emissive clay complexes at high density adsorption condition by a suppression of a molecular aggregation, which tends to decrease the photochemical activity. 相似文献
52.
A classical Lewis adduct derives from a covalent bond between a Lewis acid and a base. When the adduct formation is precluded by means of steric hindrance the association of the respective acid-base molecular system is defined as a frustrated Lewis pair (FLP). In this work, the archetypal FLP Mes3P/B(C6F5)3 was characterized for the first time by resonance Raman spectroscopy, and the results were supported by density functional theory (DFT) calculations. The charge transfer nature of the lowest energy electronic transition, from phosphine to borane, was confirmed by the selective enhancement of the Raman bands associated to the FLP chromophore at resonance condition. Herein, we demonstrate the use of resonance Raman spectroscopy as a distinguished technique to probe the weak interaction involved in FLP chemistry. 相似文献
53.
Dr. Arlin Jose Amali Dr. Hideto Hoshino Dr. Chun Wu Dr. Masanori Ando Prof. Qiang Xu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(27):8279-8282
Highly photoluminescent carbon nanodots (CNDs) were synthesized for the first time from metal–organic framework (MOF, ZIF‐8) nanoparticles. Coupled with fluorescence and non‐toxic characteristics, these carbon nanodots could potentially be used in biosafe color patterning. 相似文献
54.
Abstract The phonon-mediated resistivity is calculated for metallic carbon nanotubes based on a continuum model for electrons and phonons. In armchair nanotubes, only twisting modes contribute to the resistivity, while both stretching and breathing modes are important in zigzag nanotubes. The resistivity shows chirality dependence at low temperatures where breathing modes are not populated but becomes independent of the chirality at high temperatures. 相似文献
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57.
Purification and magnetic properties of carbon nanotubes 总被引:7,自引:0,他引:7
S. Bandow S. Asaka X. Zhao Y. Ando 《Applied Physics A: Materials Science & Processing》1998,67(1):23-27
Received: 5 January 1998 相似文献
58.
Junji Yamauchi Takashi Ando Yasuhiro Akimoto Hisamatsu Nakano 《Fiber and Integrated Optics》1996,15(4):353-363
A wavelength filter consisting of single-mode and few-mode fibers is investigated numerically. A simple finite-difference beam-propagation method, in which a transparent boundary condition can be imposed, is developed for circularly symmetric waveguides. After confirming the validity of the numerical method by the mode-mismatch loss, we calculate the propagating field in the fiber wavelength filter, in which interference between LP01, and LP02 modes occurs. To improve the filtering operation, a depressed-index fiber is employed for the few-mode fiber. The effects of the radius and refractive index of the depressed section on the transmission power are revealed and discussed. Power is suppressed to less than 0.1% at 1.3 μm, while maintaining power transmission of more than 85% at 1.55 μm. It is also found that the filtering operation shifts to higher wavelengths as the input power is increased when we choose a self-focusing nonlinear material in the depressed section. 相似文献
59.
Ohne Zusammenfassung 相似文献
60.