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161.
Kazuhiro Taguchi Shoichiro Yano Kazuhisa Hiratani Norihiko Minoura 《Journal of Polymer Science.Polymer Physics》1993,31(3):339-345
The permeability of oxygen through horizontally oriented multibilayer films of polyion complexes prepared from quaternary ammonium-type surfactants [CH3(CH2)n-1]2N+(CH3)2Br?(n = 14, 16, 18), and poly(p-styrenesulfonate) or poly[2-(acrylamido)-2-methyl-1-propanesulfonate], was measured in water using an oxygen electrode. The permeability depended mainly on the phase of the multibilayers. Thus, it increased abruptly (about 10-fold) near each phase transition temperature because of the fluidity enhancement of the multibilayer. Inverted hexagonal type nonbilayer films prepared from the polyion complexes and cholesterol had greater permeability (2–20-fold) than the multibilayer films in both phases. The large permeability of the nonbilayer films was attributed to the lack of a barrier such as the bilayer and lower crystallinity of the films. It was associated neither with an increase in thermal movement of the lipid surfactant molecules nor with an increase in the water content of the films by the addition of cholesterol. © 1993 John Wiley & Sons, Inc. 相似文献
162.
Takamasa Kinoshita Daisuke Icbinari Junko Sinya 《Journal of heterocyclic chemistry》1996,33(4):1313-1317
The Birch reduction-alkylation of some N,N-dialkylfuramides and its application to the useful intermediates for the natural product synthesis are described. 相似文献
163.
164.
P. Verma T. Ichimura T. Yano Y. Saito S. Kawata 《Laser \u0026amp; Photonics Reviews》2010,4(4):548-561
The spatial resolution in optical imaging is restricted by so‐called diffraction limit, which prevents it to be better than about half of the wavelength of the probing light. Tip‐enhanced Raman spectroscopy (TERS), which is based on the SPP‐induced plasmonic enhancement and confinement of light near a metallic nanostructure, can however, overcome this barrier and produce optical images far beyond the diffraction limit. Here in this article, the basic phenomenon involved in TERS is reviewed, and the high spatial resolution achieved in optical imaging through this technique is discussed. Further, it is shown that when TERS is combined with some other physical phenomena, the spatial resolution can be dramatically improved. Particularly, by including tip‐applied extremely localized pressure in TERS process, it has been demonstrated that a spatial resolution as high as 4 nm could be achieved. 相似文献
165.
Bis(azafulvene) was isolated in 55% yield by the reaction of 4 equivalents of phenyllithium with 5,5'-diformyl-3,3',4,4'-tetraethyl-2,2'-bipyrrole followed by quenching with acetic anhydride. Unstable bis(azafulvene)s were obtained in much higher yields by dehydrating 5,5'-bis(hydroxymethyl) derivatives of 2,2'-bipyrrole and gem-dimethyl-2,2'-dipyrrylmethane with (Boc)2O-DMAP at room temperature. X-Ray crystallography of two bis(azafulvene)s is reported. 相似文献
166.
Tetraalkylphosphonium-based amino-acid ionic liquids show lower viscosities and higher decomposition temperatures (>300 degrees C) than previously reported ammonium-based amino-acid ionic liquids. 相似文献
167.
168.
Kazuto Koike Gen-you Takada Kazuya Fujimoto Shigehiko Sasa Masataka Inoue Mitsuaki Yano 《Physica E: Low-dimensional Systems and Nanostructures》2006,32(1-2):191
Thermal stability of single-crystalline [ZnO]m[Zn0.7Mg0.3O]n multiple quantum wells (MQWs) grown on a-plane sapphire substrates by plasma-assisted molecular beam epitaxy is reported. X-ray diffraction analysis revealed that these MQWs were grown as designed with a fixed Zn0.7Mg0.3O barrier width of and a series of ZnO well widths of . Cathodoluminescence spectra from these MQWs consisted of two major peaks; one was the emission from the bound excitons in Zn0.7Mg0.3O barrier layers, and the other was that from the confined excitons in ZnO well layers. These structural and optical properties were found to be dramatically changed by the ex situ annealing treatments over 700 °C. These changes were presumably due to the onset of phase separation of the Zn0.7Mg0.3O barrier layers with pronounced Mg diffusion toward the ZnO wells. 相似文献
169.
Junko Shimazoe Richard M. Burton 《Computational & Mathematical Organization Theory》2013,19(1):78-100
Knowledge of near misses is helpful in preventing accidents, but it does not always lead to changes in organizational routines or contribute to accident prevention. In this article, the authors argue that low-probability near misses reinforce beliefs of experts and professionals in existing routines, proposing a concept of justification shift. Justification shift is underestimation of risks of known near misses vis-à-vis overestimation of reliabilities of existing routines. Consequently, signals of “close calls” tend to be disregarded, and accidents become more likely. When justification shift occurs, experts and professionals who want changes in routines face burden of proof about risks of those routines. Uncertainty in requirements and data may increase the burden and make justification shift more likely. To explore how justification shift occurs and how uncertainty influences the shift, the authors have developed an agent-based model based on theories in organizational studies and the case of the space shuttle Challenger accident in 1986. From the simulation using the model, it becomes clear that uncertainty does not make a difference in frequencies and degrees of justification shift. The authors also discuss implications of this finding to efforts to utilize knowledge of near misses and to further research on the efforts and organizational decisions. 相似文献
170.
Fine glass particles Na2O–CaO–B2O3–SiO2 are heated on glassy-carbon substrate to obtain micrometer-size solid immersion lenses (μ-SILs), and the composition dependence of the wetting property between glass melt and glassy-carbon substrate is investigated. The obtained glass particles have the super-spherical shapes with smooth surfaces. The contact angles of the particles are ranging from 125° to 147° depending on the glass composition, and there are the compositions at which the shape of the glass satisfies the optical condition of μ-SIL, showing the correlation between the contact angle and the internal structure of the glass. These results revealed that the super-spherical shape of μ-SIL can be controlled by the glass composition through the wetting property. 相似文献