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281.
Isao Yamaguchi Ayaka Kado Hiroki Fukumoto Moriyuki Sato 《European Polymer Journal》2010,46(5):1119-1130
Reactions of N-(2,4-dinitrophenyl)-4-arylpyridinium chlorides (aryl (Ar) = phenyl and 4-pyridyl) with piperazines caused the ring opening of the pyridinium ring and yielded polymers that consisted of 5-piperazinium-3-aryl-penta-2,4-dienylideneammonium chloride units [N(CH(R)CH2)2N+(Cl−)CHCHC(Ar)CHCH, RH, Me, and phenyl]. However, the same reactions occurring in the presence of piperidine yielded oligomers that consisted of 5-piperazinium-3-aryl-penta-2,4-dienylideneammonium chloride units having piperidine and/or piperazine rings at both ends. 1H NMR spectra suggested that π-electrons of the penta-2,4-dienylideneammonium group of the polymers and the oligomers were delocalized. UV-vis measurements revealed that the π-conjugation system expanded along the polymer and oligomer chains due to the orbital interaction between electrons on the two nitrogen atoms of the piperazinium ring. Conversion of the piperazinium ring from the boat form to the chair form caused decrease in the π-conjugation length. The rate constants of the conversion of the oligomers depended on their chain lengths. The surface of pellets that were molded from the polymers and oligomers exhibited metallic luster. These polymers and oligomers underwent electrochemical oxidation in solution. 相似文献
282.
Tu XL Xu HS Wang M Zhang YH Litvinov YA Sun Y Schatz H Zhou XH Yuan YJ Xia JW Audi G Blaum K Du CM Geng P Hu ZG Huang WX Jin SL Liu LX Liu Y Ma X Mao RS Mei B Shuai P Sun ZY Suzuki H Tang SW Wang JS Wang ST Xiao GQ Xu X Yamaguchi T Yamaguchi Y Yan XL Yang JC Ye RP Zang YD Zhao HW Zhao TC Zhang XY Zhan WL 《Physical review letters》2011,106(11):112501
Mass excesses of short-lived A=2Z-1 nuclei (63)Ge, (65)As, (67)Se, and (71)Kr have been directly measured to be -46,921(37), -46,937(85), -46,580(67), and -46,320(141) keV, respectively. The deduced proton separation energy of -90(85) keV for (65)As shows that this nucleus is only slightly proton unbound. X-ray burst model calculations with the new mass excess of (65)As suggest that the majority of the reaction flow passes through (64)Ge via proton capture, indicating that (64)Ge is not a significant rp-process waiting point. 相似文献
283.
Ishikawa T Yoshida N Ueno H Wiedeman M Imai Y Yamaguchi T 《Physical review letters》2011,107(2):028102
Coherent structures appear in a concentrated suspension of swimming bacteria. While transport phenomena in a suspension have been studied extensively, how energy is transported from the individual cell scale to the larger mesoscale remains unclear. In this study, we carry out the first successful measurement of the three-dimensional velocity field in a dense suspension of bacteria. The results show that most of the energy generated by individual bacteria dissipates on the cellular scale. Only a small amount of energy is transported to the mesoscale, but the gain in swimming velocity and mass transport due to mesoscale coherent structures is enormous. These results indicate that collective swimming of bacteria is efficient in terms of energy. This paper sheds light on how energy can be transported toward smaller wave numbers in the Stokes flow regime. 相似文献
284.
H. Matsui K. Tsukada T. Tsuchiya M. Sohma I. Yamaguchi T. Kumagai T. Manabe 《Physica C: Superconductivity and its Applications》2011,471(21-22):960-962
We have studied the crystallization time dependence of the epitaxial YBCO films (t = 0.8 μm) grown on CeO2-buffered SrTiO3 substrates by fluorine-free metal–organic deposition using uv-lamp irradiation (uv-MOD). As increasing the time (T0) for heat treatment at the reaction temperature (760 °C) from 0 to 90 min, Jc and the YBCO 0 0 l XRD intensity are steeply increased and reach their maximum values at T0 = 10 min. This suggests that the heat treatment required for YBCO crystallization is significantly shortened in uv-MOD compared to conventional all-pyrolytic F-free MOD processes, which consume T0 = 90–150 min for crystallizing 0.4–0.5-μm-thick films. Scanning electron microscope measurement revealed a drastic change in surface morphology between T0 = 8 and 10 min, showing a good correspondence to the Jc and XRD data which suggest that the epitaxial growth reaches the film surface at the very early stage in the heat treatment. 相似文献
285.
286.
K. Yamaguchi M. Fujii T. Inoue M. Haraguchi T. Okamoto M. Fukui 《Applied Physics A: Materials Science & Processing》2011,103(3):721-724
A planar bilayered silver prisms with rounded corner is shown to have a singular optical mode depends of gaps by numerical
simulation. Such behavior results from the plasmon resonance in the pairs of nanoprisms both the electric and the magnetic
components of light. 相似文献
287.
Kentaro Hatsumi Dolors Berga Shigehiro Serizawa 《International Journal of Game Theory》2014,43(1):153-168
Following “Barberà et al. (1991, Econometrica 59:595–609)”, we study rules (or social choice functions) through which agents select a subset from a set of objects. We investigate domains on which there exist nontrivial strategy-proof rules. We establish that the set of separable preferences is a maximal domain for the existence of rules satisfying strategy-proofness and no-vetoer. 相似文献
288.
289.
Yuhiro Iwamoto Hiroshi Yamaguchi Xiao-Dong Niu 《Journal of magnetism and magnetic materials》2011,323(10):1378-1383
The magnetic body force in boiling two-phase temperature-sensitive magnetic fluid (TSMF) flow is known to effectively increase the driving force of magnetic fluid in a non-uniform magnetic field. Based on this mechanism, in the present study, a binary TSMF, which is a mixture of the TSMF and a low-boiling-saturation-temperature organic solution, is proposed to be used in a heat transport device to enhance its circulation. In order to see its performance in the heat transport device, the pressure difference at different heated temperatures, magnetic fields and inclination angles of the heating section are investigated experimentally and theoretically. Results showed that the driving force increases remarkably due to more gas phase appearing in the test fluid and the magnetization of it decreasing. At low magnetic field the driving force is enhanced greatly when the inclination angle is close to 60°, while at high magnetic field the driving force is remarkably enhanced due to the effect of the magnetic force in the inclination angle range from 0° to 30° and 60° to 90°. 相似文献
290.
Aiko Fukazawa Taka-aki Murai Liangchun Li Youming Chen Shigehiro Yamaguchi 《Comptes Rendus Chimie》2010,13(8-9):1082-1090
The PCl3-promoted intramolecular cascade cyclization produced a series of thiophene-fused phospholo[3,2-b]phosphole derivatives, including non-oxidized 2, dioxides 3, and disulfides 4. These derivatives exhibit significantly red-shifted absorptions and fluorescences compared with their benzene-fused analogues. Among the thiophene-fused series, the non-oxidized 2 has the highest fluorescence quantum yield of 0.95. This trend is in contrast to that observed for the benzene analogues, in which a dioxide derivative shows the most intense fluorescence. 相似文献