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Yoshio Inoue Akio Takahashi Yasuo Tokit Riichir Chûj Yasuhiro Miyoshi 《Magnetic resonance in chemistry : MRC》1974,6(9):487-491
Carbon-13 NMR spectra of all-trans retinal1 and vitamin A1 were measured by the pulse Fourier transform method in CCl4. All peaks in these spectra were assigned from considerations of chemical shifts, half proton-decoupled spectra, spin-lattice relaxation times and induced chemical shift by the addition of shift reagent. The carbon-13 NMR spectrum was also measured for all-trans retinal1 which had been exposed to the sunlight for three hours, and the induced isomer was proposed to be 11-s-cis retinal1. 相似文献
124.
Dynamic mechanical measurements were conducted for several kinds of ultra–high-strength polyethylene fibers with different methyl branch contents. As is the case with conventional polyethylene materials, UHSPE fibers also exhibit α, β, and γ-relaxation dispersions. Each relaxation process is the function of both the tensile moduli and the branch contents of UHSPE fibers. It was also found that the γ-process of UHSPE fibers is dominated mainly by the localized molecular motion in the crystalline part, such as a dislocation mode of crystallite defects, which is very sensitive to the branching content. From the time and temperature superposition of the frequency dispersion experiments, it was found that activation energies for both the α2-process and α3-process increase proportionally to the methyl branch content, while the α1-process is not so affected by the branch content. This result shows that the incorporated branch sites in the crystalline part effectively hinder the chain-to-chain slippage; meanwhile, they have not hindered the slippage at the grain boundary so far, which also enables us to explain the creep improvement of UHSPE fibers through branch incorporation with the same mechanism. © 1994 John Wiley & Sons, Inc. 相似文献
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To eliminate the temperature dependence of narrow-band filter, a three-dimensional athermal waveguide of which optical path length is independent of temperature was developed at 1.3 μm wavelength. The temperature coefficient of the refractive index of films made of glass materials was measured at this wavelength, and a strip-loaded athermal waveguide was designed using a scalar finite element method. The temperature coefficient of optical path length was successfully decreased to 9.65X10-9[/K] (0.1% of the conventional waveguide). 相似文献
128.
Yasuo Watatani 《Journal of Functional Analysis》1996,140(2):312
LetNbe an irreducible subfactor of a typeII1factorM. If the Jones index [M:N] is finite, then the set
at(NM) of the intermediate subfactors for the inclusionNMforms afinitelattice. The commuting and co-commuting square conditions for intermediate subfactors are related to the modular identity in the lattice
at(NN). In particular, simplicity of a finite groupGis characterized in terms of commuting square conditions of intermediate subfactors forNM=NG. We investigate the question of which finite lattices can be realized as intermediate subfactor lattices. 相似文献
129.
Setsuji Tone Kouichi Shinohara Yasuo Igarashi Tsutao Otake 《Journal of membrane science》1984,19(2):195-208
Investigations were made of the water flux rate and rejection characteristics of aromatic substances in aqueous solutions using a thin, dense cellulose acetate membrane in reverse osmosis experiments. The aromatic substances used were phenol, aniline, hydroquinone and p-chlorophenol. The permeate became more enriched in aromatic compounds as compared to the feed solution as the water content of the membrane increased. By considering both the effects of pressure on the chemical potential of a component and the contribution of viscous flow to the overall transport of that component in the hydrated membrane, a theoretical relationship was developed to predict the negative solute rejection of the membrane. Based on this proposed theory, the permeability coefficients of water and organic solute were estimated from experimental solute rejection data, including negative values. The permeability coefficients of components were in good agreement with previously established correlations in measurements of partition and diffusion coefficients. 相似文献
130.
Tohru Niida Yasuo Kousaka Shinji Oda 《Particle & Particle Systems Characterization》1988,5(3):139-143
The method described is based on the fact that the measurement of particles in the gaseous phase is generally easier than that in the liquid phase for fine particles smaller than 1 μm in diameter. The system consists of a liquid nebulizing unit, evaporator, condenser, mixing diluter and two different aerosol sizing instruments. It has been found that this method can continuously detect particulate impurities in ultrapure water in situ and can measure the size distribution of fine powders in the submicron particle size range down to about 0.05 μm. 相似文献