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71.
T. Ossaka K. Kakegawa T. Oi M. Mukaida 《Journal of Radioanalytical and Nuclear Chemistry》1994,183(2):235-244
Determination of major elements in natural solid samples by X-ray fluorescence spectroscopy (XRF) with a fusion disc technique is described. Data obtained by the present XRF analytical system were found to have satisfactorily high reliability. Five rock samples and a volcanic ash sample with varying ages ranging from the present to 180 000 years, derived by the current and past volcanic activities in the Unzen area, Nagasaki, Japan were analyzed for their major elements' compositions using the above mentioned system. The chemical composition of the magma under this area has changed very little at least over the last 180 000 years. 相似文献
72.
Synthesis and properties of optically active 1,3-diols and their derivatives as chiral dopants for ferroelectric liquid crystals 总被引:1,自引:0,他引:1
Tetsuo Kusumoto Ken-Ichi Sato Kumiko Ogino Tamejiro Hiyama Sadao Takehara Masashi Osawa Kayoko Nakamura 《Liquid crystals》1993,14(3):727-732
New chiral dopants β-hydroxy ketones 1, 1,3-diols 2, 1,3-dioxanes 3 and 1,3-dioxan-2-ones 4 were designed and synthesized. Reaction of (R)-1,2-epoxyoctane with carbanions derived from 2-(4-substituted phenyl)-1,3-dithianes followed by hydrolysis of the resulting hydroxy dithianes afforded 1. Reduction of 1 gave the diols 2, which yielded 3 upon acetalization and 4 upon carbonation. The syn isomers of 2, 3, and 4 exhibited larger spontaneous polarizations, when applied as chiral dopants, than the anti isomers or hydroxy ketones 1. 相似文献
73.
R Okutani Y Itoh H Hirata T Kasahara N Mukaida T Kawai 《Journal of chromatography. A》1992,577(1):25-35
A simple and high-yield purification procedure for urine protein 1 (UP1) using anti-UP1 immunoaffinity chromatography is described. Pure UP1 was obtained in a final yield of 60.2%, and observed as a single electrophoretic band and as a single peak on reversed-phase high-performance liquid chromatography. The N-terminal amino acid residue of UP1 was found to be glutamic acid, contrary to what was reported previously. Furthermore, the N-terminal sequence of UP1 up to 53 amino acids was confirmed to be identical with that of mature human Clara cell 10-kilodalton protein, which inhibits phospholipase A2 activity. 相似文献
74.
Moriyuki Sato Yuji Tada Yusuke Goto Ken-ichi Mukaida 《Macromolecular rapid communications》1995,16(2):139-146
Novel semi-rigid fluorocarbon-containing coplycarbonates composed of biphenyl moiety and rigid rod-like hexafluoropentane chain were prepared by melt polycondensation of 6,6′-(biphenyl-4,4′-diyldioxy)dihexanol ( 1 ) and 2,2,3,3,4,4-hexafluoro-1,5-pentanediol ( 2 ) with alkylene diphenyl dicarbonates 3 of various aliphatic lengths (m = 6, 8, 10 and 12). The structures of the copolymers 4 were confirmed by FT-IR, 1H and 13C NMR spectra and elemental analyses. The thermal and liquid-crystalline (LC) properties were examined by differential scanning calorimetry (DSC), polarizing microscopy and temperature-changeable X-ray analyses. These measurements indicated that the copolymers show well-defined thermotropic nematic textures and have block-like sequences. It is suggested that the introduction of the hexafluoropentane chain into the main chain gives more stable LC phases. 相似文献
75.
Masakazu Anpo Takaiki Nomura Junko Kondo Kazunari Domen Ken-Ichi Maruya Takaharu Onishi 《Research on Chemical Intermediates》1990,13(3):195-202
Photoluminescence and FT-IR studies of the adsorption of H2 on ZrO2 catalysts have been performdd to clarify the true natuee of active surface sites for the activaiion of H2 in connection with the CO — H2 reaction on the catalyst. The results indicate that the coordinatively unsaturated surface sites with different coordination
numbers are generated on the surfaces by evacuation at temperatures higher than 600 K. These surface sites of lower coordination
play a significant role in the reversible and irreversible dissociative adsorption of H2 on the active ZrO2 catalyst. The former seems to act as active hydrogen species for the CO — H2 reaction to form branched hydrocarbons on the ZrO2 catalyst. 相似文献
76.
The time evolution of the density fluctuation of molecules inhomogeneously dispersing in a mesoscopic volume is investigated by dynamic light scattering in several fluids in supercritical states. This study is the first time-domain investigation to compare the dynamics of density fluctuation among several fluids. The samples used are non-hydrogen-bonded fluids in the supercritical states: CHF(3), C(2)H(4), CO(2), and xenon. These four molecules have different properties but are of similar size. Under these conditions, the relationship between dynamic and static density inhomogeneities is studied by measuring the time correlation function of the density fluctuation. In all cases, this function is characterized by a single exponential function, decaying within a few microseconds. While the correlation times in the four fluids show noncoincidence, those values agree well with each other when scaled to a dimensionless parameter. From the results of this scaling based on the Kawasaki theory and Landau-Placzek theory, the relation between dynamics and static structures is analyzed, and the following four insights are obtained: (i) viscosity is the main contributor to the time evolution of density fluctuation; (ii) the principle of corresponding state is observed by the use of time-domain data; (iii) the Kawasaki theory and the Landau-Placzek theory are confirmed to be applicable to polar, nonpolar, and nondipolar fluids that have no hydrogen bonding, at temperatures relatively far from critical temperature; and (iv) the density fluctuation correlation length and the value of density fluctuation are estimated from the time-domain data and agree with the values from other experiments and calculations. 相似文献
77.
Jean-François Bisson Akira Shirakawa Youhei Sato Yuri Senatsky Ken-Ichi Ueda 《Optical Review》2004,11(6):353-357
A Nd:YAG rod active element placed inside a resonator was pumped by the second harmonic radiation (the wavelength =0.532 m) of a Q-switched Nd:YAG laser diffracted at a circular aperture. Various distributions of pumping intensity in the Fresnel (near-field) region along the direction of the pump beam diffraction were produced. Inversion profiles with maxima or minima at the resonator axis were formed in the active element, depending on its distance from the circular aperture. Gain-switched operation of the Nd:YAG rod laser at =1.064 m is reported at the fundamental mode and also at the TEM01, TEM01* and other higher-order modes for different positions of the active element in the near-field region. Applications of such diffractive optical pumping for the concentration of the pumping radiation into the active media and for laser beam profling are discussed. © 2004 The Optical Society of Japan 相似文献
78.
Let C be a smooth, complex, projective curve of genus 3. By choosing an unramified double covering of C, the Abel-Prym map yields an embedding of C into a Kummer surface K when C is non-hyperelliptic. We compute the Quillen metric on the determinant of the cohomologies of with respect to the metric on C induced from the flat Kähler metric on K. For the computation of the Quillen metric, we show the exact self-duality of the Heisenberg-invariant Kummer's quartic surfaces. 相似文献
79.
Ken-Ichi Okamoto Kazuhiro Tanaka Hidetoshi Kita Asumaru Nakamura Yoshihiro Kusuki 《Journal of Polymer Science.Polymer Physics》1989,27(13):2621-2635
CO2 sorption and transport were investigated for the polyimide prepared from 3,3′,4,4′-biphenyltetracarboxylic dianhydride (BPDA) and 4,4′-diaminodiphenyl sulfone (DDS). The morphology of films did not change on annealing above the glass transition temperature and remained amorphous unlike the polyimide prepared from BPDA and 4,4′-oxydianilline (ODA). This seems to be due to the strong hindrance to rotation of the sulfonyl linkage. Sorption and transport data were analyzed according to the dual-mode model. Solubility, diffusion, and permeability coefficients at 20 atm and 80°C for BPDA-DDS polyimide were substantially equal between as-cast and annealed films and were 1.7, 2.2, and 3.7 times greater, respectively, than for the as-cast films of the BPDA-ODA polyimide. The higher solubility was due to larger values of the Henry's law solubility constant kD, Langmuir capacity constant C, and the Langmuir affinity constant b. The sorption and transport properties were compared with those for amorphous glassy aromatic polymers including other polyimides. The relation of k, C, b, and the diffusion coefficients in the Henry's law population and the Langmuir population (DD and DH) with other properties of the polymers were discussed. Values DD and DH for BPDA-DDS polyimide were much larger than expected from the estimated free-volume fraction. 相似文献
80.