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941.
J. S. Zheng Y. Kobayashi J. Nakamura K. Asai G. L. Zhang F. Ambe 《Hyperfine Interactions》1992,68(1-4):307-310
151Eu Mössbauer spectroscopy on Eu VO3 in the temperature range of 9-293 K indicated that there is a large increase ofeV zzQg when temperature goes from 293K down to 9K. 相似文献
942.
Susumu Ikeda Masashi Jimbo Shin'Ichi Kobayashi Yasaku Wada 《Journal of Polymer Science.Polymer Physics》1985,23(9):1781-1791
The effect of the depolarization field in crystallites on the ferroelectric behavior of polymers is discussed on the assumption that the crystallite is a prolate ellipsoid with its major axis directed along the electric field. The theory relates the polarization P and the electric field E in the crystallite to the overall values P and E for the polymer. The determination of the P -E hysteresis of a crystallite from the P-E hysteresis is given with examples for poly(vinylidene fluoride) (PVDF) and vinylidene fluoride (VDF)–trifluoroethylene (TrFE) copolymer. The ratio R = J/(Ps ? P), with J the switching current density and Ps the saturation polarization of polymer, is proved to be free from the depolarization field effect and the plot of logR against logarithmic time is shown to have merit for characterization of switching behavior. Examples of the curves are given for PVDF and VDF-TrFE copolymers. The temporal change of local electric field in the unreversed domains in the crystallite in the course of polarization reversal is predicted by the theory and this change is proved to be a significant mechanism of switching acceleration. 相似文献
943.
944.
Junji Nakano Moon Yul Huh Yoshikazu Yamamoto Takeshi Fujiwara Ikunori Kobayashi 《Computational Statistics》2004,19(1):137-146
Summary Jasp is an experimental general purpose Java-based statistical system which adopts several new computing technologies. It
has a function-based and object-oriented language, an advanced user interface, flexible extensibility and a server/client
architecture with distributed computing abilities. DAVIS is, on the other hand, a stand-alone Java-based system, and is designed
for providing advanced data visualization functions with easy operations by a GUI. In this paper, it is made possible to use
tools of DAVIS from within Jasp, in order that the new integrated system can handle not only data filtering and statistical
analysis but also data visualization. We develop a mechanism for extending the server/client system of Jasp to realize an
efficient collaboration with DAVIS in the client-side. It is shown that the mechanism is straightforward and simple. 相似文献
945.
Yuji Kobayashi 《Semigroup Forum》1992,45(1):23-25
Communicated by G. Lallement 相似文献
946.
Noriko Nakagawa Takafumi Yamada Koji Akioka Susumu Okubo Shojiro Kimura Hitoshi Ohta 《International Journal of Infrared and Millimeter Waves》1998,19(2):167-176
New systems for millimeter and submillimeter wave ESR have been developed in Kobe University. In the previous system the pulsed magnetic field was limited up to 17 T in the temperature range from 1.8 to 86 K. Using the new systems, we can measure in the field range up to 30 T in the temperature range from 1.8 K to 4.2 K and from 18 K to room temperature. The resolution of the magnetic field has been also improved in the new ESR system. The details of our new ESR systems are presented. In addition, the measurements of Yb2Cu2O5 using these new systems are presented. 相似文献
947.
948.
Rotational isomerism occurring in solid state of organic long-chain compounds, including synthetic linear polymers, have been concerned in connection with the macroscopic physical properties of bulk materials. The conformational order in the non-crystalline part of polyethylene has been investigated by Raman spectra, and related to the elastic behaviors of bulk samples. In the solid-state phase transition induced by mechanical forces of poly(butylene terephthalate) the macroscopic strain has been related directly to the conformational conversion of the molecules. Concerning the piezoelectric and pyroelectric activities of poly(vinylidene fluoride), polymorphism, phase transition, and structural change on the poling process have been investigated. A ferroelectric-paraelectric phase transition has been found for a series of copolymers of vinylidene fluoride and trifluoroethylene. On the phase transition a great change in molecular conformation is accompanied with the scrambling of the dipolar orientation. This is the characteristic of polymer ferroelectrics in which the dipolar units are linked with each other by covalent bonds in a molecular chain. Spectroscopic evidences are presented indicating that the thermodynamic stability of polymorphs of n-fatty acids is closely related to the rotational isomerism occurring in the carboxyl groups. 相似文献
949.
Takeo Taguchi Tomoyuki Takigawa Yumiko Tawara Tsutomu Morikawa Yoshiro Kobayashi 《Tetrahedron letters》1984,25(49):5689-5692
β-Fluoroallyl alcohols () were obtained with high stereoselectivity by the LiA1H4 reduction of 1-acetoxy-3-alkyl-2,2-difluorocyclopropanes (). 相似文献
950.
Motomasa Kobayashi Nobuyoshi Shimizu Isao Kitagawa Yoshimasa Kyogoku Nobuyuki Harada Hisashi Uda 《Tetrahedron letters》1985,26(32):3833-3836
The absolute stereostructures of two pentacyclic hydroquinones, halenaguinol () and halenaquinol sulfate () from the Okinawan marine sponge Xestospongia sapra, have been determined by means of theoretical calculation of CD spectra. 相似文献