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81.
Satoshi Fukui Osami Tsukamoto Kazuaki Negishi 《Physica C: Superconductivity and its Applications》1998,310(1-4):142-146
We investigated the AC loss characteristics of a low temperature NbTi AC wire by measuring the AC transport current losses in the external AC magnetic field whose components are the longitudinal and transverse ones. The measurement results showed that the AC losses were significantly dependent on the directions and magnitudes of the external longitudinal field component. The AC losses caused by the longitudinal and azimuthal field components were estimated by our previously derived model. The theoretical results well explained the dependence of the AC losses on the longitudinal field components. It was also shown that the AC losses can be substantially reduced by the proper choice of the twisting way. 相似文献
82.
Yoshio Tanigawa Kazuaki Nishimura Akihiko Kawasaki Shun-Ichi Murahashi 《Tetrahedron letters》1982,23(52):5549-5552
Allyl diethyl phosphates (1) can be easily substituted with malonates and amines in the presence of palladium(O) catalyst. Synthetic utility of the reaction is demonstrated by the sequential amination-amination and alkylation-amination of (Z)-4-acetoxybut-2-enyl diethyl phosphate (1b) with high regio- and stereoselectivity. 相似文献
83.
84.
Shigeru Nishiyama Yoshikazu Shizuri Daizo Imai Shosuke Yamamura Yukimasa Terada Masatake Niwa Kazuaki Kawai Hideyuki Furukawa 《Tetrahedron letters》1985,26(27):3243-3246
Isocitreoviridinol has been newly isolated from the mycelium of B. (IFO 6050) together with citreoviridinol, and their stereostructures have also been elucidated by means of chemical method: the 2,6-dioxabicyclo[3.2.1]octanes have been made, one of which is regarded as a promising synthetic intermediate of citreoviridinol. In addition, isocitreoviridinol diacetate has been derived from citreoviridin in 3 steps. 相似文献
85.
Atsuomi Shundo Megumi Fukui Makoto Takafuji Kazuaki Akasaka Hiroshi Ohrui Dusan Berek Hirotaka Ihara 《Analytical sciences》2007,23(3):311-315
2-(2,3-anthracenedicarboximido)cyclohexane derivatives (AC) have been known as the evolutionary diastereomerizing reagents for enantiomer discrimination in HPLC with ODS. However, a substantial separation of diastereomers can be observed only at lower temperatures, such as -40 degrees C. Therefore, in this work, poly(octadecyl acrylate)-grafted silica, ODAn was applied as an alternative stationary phase to ODS for the separation of AC-derived diastereomers. As a result, complete separation was achieved even under the conventional condition: for example, methanol as the mobile phase and 0 degrees C as the column temperature. An investigation on the temperature dependency of the selectivity demonstrated that ODAn shows a remarkable increase in selectivity at temperatures below 30 degrees C, which almost agreed with the peak-top temperature of the endothermic peak in a DSC thermogram for ODA35 immersed in a mobile phase. The better separation would be derived from a highly ordered structure of ODAn and a carbonyl-pi interaction with AC-derived diastereomers. 相似文献
86.
On irradiation cyclic thioimides with N-ω-phenylalkyl substituents undergo the Norrish type II cyclization when benzylic hydrogen is available at the δ or ε-position of the thiocarbonyl group. 相似文献
87.
Mitiko Miura Hitoshi Arimori Hiromu Murata Akiko Kida Kazuaki Iishi 《Journal of Physics and Chemistry of Solids》1983,44(7):627-631
The effect of the electronic extension on the electrostatic potential was first taken into account functionally by Birman. We have applied his model to the lattice dynamics of CaO, where the degree of the electronic extension w was defined and determined with the use of the electronic charge density distribution obtained from analysis of X-ray data. Our treatment shown here not only gives a physically meaningful model including the feature of the electronic extension, but also involves essentially the same very simple process as the conventional point-charge model but with fewer adjustable parameters. Good reproduction of calculated phonon dispersion curves was obtained by taking into account the electronic extension, although the degree of the electronic extension, w, used to fit the curve was a little larger than that derived from the observed data owing to the first rough approximation for the potential energy arising from the electronic extension. 相似文献
88.
89.
Kazuaki Fukamichi Hidetoshi Hiroyoshi Michio Kikuchi Tsuyoshi Masumoto 《Journal of magnetism and magnetic materials》1979,10(2-3):294-299
The thermal expansion and magnetic properties of Fe-B and Fe-P amorphous alloys prepared from melts have been investigated. These amorphous alloys show distinct Invar characteristics. heir magnetic properties are also very similar to those of Fe-Ni crystalline Invar alloys; that is, the high-field susceptability and forced-volume magnetostriction are remarkably large, the magnetic moment per Fe atom does not increase linearly, the Curie temperature decreases with a decrease in concentration of B or P, and their reduced their magnetization curves are much flatter than those of crystalline pure Fe. 相似文献
90.
Yoshiharu Sato Kazuaki Sugawa Michiaki Kawaguchi 《Reports on Mathematical Physics》1979,16(1):111-119
The differential geometrical consideration of the parameter space, especially as a Riemannian geometry, was initiated by C.R. Rao in 1945. This approach appears to be important for the problem of estimation and test of hypotheses as well as for applications to physical problems. It has been shown that the parameter spaces of univariate normal distribution, univariate exponential distribution and multinomial distribution are Riemannian spaces of constant curvature. In the present paper the discussion is confined to the parameter space of the two-dimensional normal distribution. It has been shown that in general the parameter space is not necessarily of a constant curvature and that, if the correlation coefficient vanishes, the parameter space becomes an Einstein space. In addition, some invariant quantities, as sectional curvature, mean curvature and scalar curvature, have been calculated. 相似文献