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161.
162.
Kazumichi Iwasa 《Journal of Difference Equations and Applications》2013,19(12):1305-1314
In this paper, we extend Doi et al. (2007) in the sense that households in both countries consume a durable good. Although this generalization makes the model much complicate, it will be shown that under the standard Cobb–Douglas preferences, the model has a unique steady state and saddle-point stability. 相似文献
163.
164.
Satoshi Tatsuura Osamu Wada Makoto Furuki Minquan Tian Yasuhiro Sato Izumi Iwasa Lyong Sun Pu 《Optical and Quantum Electronics》2001,33(7-10):1089-1099
Based on a time-to-space conversion technique, a two-dimensional serial-to-parallel pulse converter using a squarylium dye J-aggregate film is proposed. The squarylium dye J-aggregate film, which exhibits an ultrafast recovery of bleached absorption, operates as a large-area femtosecond all-optical shutter. The system is composed of a few simple optical components and enables conversion of temporally serial signals into multiple parallel outputs in one- or two-dimensional space. The serial-to-parallel conversion of 1 Tb/s optical pulses was demonstrated and different 4-bit signal patterns were successfully discriminated in one dimension. Also, 2 × 2 outputs were clearly observed as two-dimensional outputs using this converter. 相似文献
165.
166.
Satoru Mashimo Shin Yagihara Yasuo Iwasa 《Journal of Polymer Science.Polymer Physics》1978,16(10):1761-1771
The dielectric absorption due to the side-group rotation of the methyl methacrylate (MMA) unit in MMA-styrene and MMA-p-chlorostyrene (pCS) copolymers was measured. The relaxation time for MMA-pCS copolymers with low MMA contents could be interpreted quantitatively in terms of the Kramers rate-constant theory at the low-friction limit. On the other hand, the frictional effect on the relaxation time could not be ignored for any copolymers except for the MMA-pCS copolymers with low MMA contents. The relaxation time for pure poly(methyl methacrylate) could be interpreted by the Kramers theory at the high-friction limit. 相似文献
167.
Satoru Tokutomi Tatsuo Iwasa Tru Yoshizawa Shun-ichi Ohnishi 《Photochemistry and photobiology》1981,33(4):467-474
Abstract— Flash-induced changes in surface potential and fluidity of purple membrane were studied by a spin label method. Changes in surface potential and fluidity were monitored by observing the distribution of charged and uncharged spin labels between the purple membrane and the aqueous phase.
On flash illumination, a transient hyperpolarization of the surface potential and a transient fluidization of the membrane hydrophobic region are induced. The former may probably reflect the proton movement near the purple membrane surface, while the latter may result from photo-induced conformational changes of bacteriorhodopsin.
The two events are different in time course. The relationships between the two events, and the formation and decay of the intermediates of bacteriorhodopsin in the photoreaction cycle are discussed. 相似文献
On flash illumination, a transient hyperpolarization of the surface potential and a transient fluidization of the membrane hydrophobic region are induced. The former may probably reflect the proton movement near the purple membrane surface, while the latter may result from photo-induced conformational changes of bacteriorhodopsin.
The two events are different in time course. The relationships between the two events, and the formation and decay of the intermediates of bacteriorhodopsin in the photoreaction cycle are discussed. 相似文献
168.
R. Kita K. Suzuki T. Takeuchi T. Iwasa O. Miura Y. Ichino T. Yoshimura Y. Yoshida K. Yamada K. Kaneko A. Ichinose 《Physica C: Superconductivity and its Applications》2011,471(21-22):859-862
The stability of various amounts of Ba3Cu3In4O12 (334) or BaTbO3 (BTO) in a sintered YBa2Cu3Oy (YBCO) matrix was examined. Samples with added 334 or BTO exhibited critical temperatures (Tc) above 90 K for up to 20 vol.% addition and improved critical current densities (Jc) under a magnetic field. X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy-dispersive X-ray (EDX) analysis indicated that 334 and BTO did not react with the YBCO matrix under the sintering conditions used. The normalized Jc under a magnetic field of 1 T reached a maximum at 14 vol.% of 334 addition and 20 vol.% BTO addition. YBCO thin films with added BTO showed a gradual decrease in the Tc with increasing BTO content. YBCO films with added 334 showed a constant Tc of 87 K up to a 334 content of 4 vol.%. 相似文献
169.
H Shibata H Saito C Yomota T Kawanishi H Okuda 《Chemical & pharmaceutical bulletin》2012,60(9):1105-1111
We have investigated the effects of two bile salts, chenodeoxycholate (CDC) and ursodeoxycholate (UDC), and a widely used detergent, Triton X-100 (T(X-100)), on normal and poly(ethylene glycol)-modified liposomes (PEGylated liposomes). We tested various lipid compositions, including hydrogenated soybean phosphatidylcholine/cholesterol/PEG-conjugated lipid (HSPC/PEG-lipid). Alterations in permeability were determined by the rate of drug release from the liposomes and solubilization was assessed by measuring the particle size of liposomes. In addition, we attempted to observe interactions between the detergents and lipid bilayers by using surface plasmon resonance (SPR). CDC induced drug release from liposomes in a dose-dependent manner, and the PEGylated liposomes tended to be susceptible to CDC. While UDC did not strongly induce drug release from liposomes, UDC exhibited a similar tendency with CDC. In case of T(X-100), there were significant differences in the percentage of released drug between normal and PEGylated liposomes, and the percentage of T(X-100)-induced drug release further increased with an increased ratio of PEG-lipid. SPR analysis revealed that the lipid bilayer including PEG-lipid was selectively solubilized by T(X-100), correlating with the drug release data. These results suggest that the effect of detergents on the lipid bilayer of liposomes depends on both the kind of detergent and the lipid composition, including the presence or absence of PEG-lipid. Moreover, the effects of T(X-100) on the lipid bilayers of the PEGylated liposomes significantly differed from those on the lipid bilayers of the normal liposomes. 相似文献
170.