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921.
Takayo Takigawa Hideo Ogawa Masanori Nakamura Katsutoshi Tamura Sachio Murakami 《Fluid Phase Equilibria》1995,110(1-2):267-281
Molar excess enthalpies HmE, isobaric heat capacities CP,mE, volumes VmE and isothermal compressibilities κTE for the 1,3-dioxane(3DX) + cyclohexane mixture were measured at 298.15 K, in order to compare to those of the 1,4-dioxane(4DX) + cyclohexane mixture. HmE is endothermic and the maximum value about 1.5 kJ mol−1 at x ≈ 0.45, and lower than that of the 4DX mixture by about 80 J mol−1. VmE is positive over the whole concentration and the maximum value is about 0.85 cm3 mol−1 at x ≈ 0.45, and lower than that of the 4DX mixture. The above results suggest the energetic unstabilization, resulting in the volume expansion in the mixture. CP,mE shows the characteristic W-shaped concentration dependence, which has maximum at x ≈ 0.45 and two minima at x ≈ 0.1 and 0.9. The maximum CP,mE value for 3DX mixture shifts toward the positive side, compared to that of 4DX mixture. κTE were estimated from speeds of sound, densities, thermal expansion coefficients and isobaric heat capacities of the pure component liquids and the mixtures. The κTE result shows the positive concentration dependence over the whole composition range. The 3DX mixture has the similar thermodynamic properties to the 4DX mixture, despite that 4DX is the nonpolar solvent and 3DX is the dipolar liquid. this means that there exists the local dipolar interaction between 4DX molecules, and the prevalence of “microheterogeneity” in the both mixtures. 相似文献
922.
923.
924.
Kaoru Nakamura Masato Higaki Kazutoshi Ushio Shinzaburo Oka Atsuyoshi Ohno 《Tetrahedron letters》1985,26(35):4213-4216
Ketones in β-keto esters are reduced asymmetrically by immobilized bakers' yeast. The configuration and the enantiomer excess of the products are dramatically changed by the entrapment of yeast cells in dense polyurethane matrices. 相似文献
925.
926.
Osamu Nakamura 《Ionics》1995,1(1):21-28
In the search for the improvement the conduction properties of composite ceramics, we have found a conductivity enhancement
by two orders of magnitude when ferroelectric PZT particles are dispersed into an NZS particle matrix. Ferroelectric BaTiO3 particle dispersion has shown that the enhancement does not depend on the particle size, but depends on the magnitude of
dielectric constant. An application of solid super acid particles such as ZrO2 treated with sulfuric acid is another example to enhance the conductivity. Lithium compounds also have the effect to enhance
the conductivities in other lithium ion conductor systems.
Paper presented at the 1st Euroconference on Solid State Ionics, Zakynthos, Greece, 11 – 18 Sept. 1994 相似文献
927.
Y. Homma M. Nakada A. Nakamura S. Nasu D. Aoki H. Sakai S. Ikeda E. Yamamoto Y. Haga Y. Ōnuki Y. Shiokawa 《Hyperfine Interactions》2006,168(1-3):1175-1179
57Fe and 237Np Mössbauer ōmeasurements have been performed for NpFeGa5, which is one of the so-called neptunium 1-1-5 compounds. The 57Fe Mössbauer spectra below T N = 118 K show the magnetically ordered state. The magnitude of the hyperfine magnetic field at the 57Fe nucleus is determined to be 1.98 ± 0.05 T at 10 K. From the 237Np Mössbauer spectrum at 10 K, the hyperfine magnetic field at the 237Np nucleus is 203 T and the hyperfine coupling constant is determined to be 237 T/μB using the Np atomic magnetic moment of 0.86 μB determined by the neutron diffraction study. 相似文献
928.
Mariko Kitajima Mio Nakamura Hiromitsu Takayama Kazuki Saito Joachim Stöckigt Norio Aimi 《Tetrahedron letters》1997,38(52):1017-9000
The regeneration of plantlets was successful from Ophiorrhiza pumila callus cultures, from which a new glucosyloxy camptothecin, 9-β-glucosyloxycamptothecin, together with 15 metabolites including six camptothecin-related alkaloids was isolated. (3S)-Deoxypumiloside, one of the plausible biogenetic precursors of camptothecin, could not be found, whereas the (3R) epimer was isolated from the regenerated plants. 相似文献
929.
Shu Nakamura 《Journal of Functional Analysis》2003,205(1):180-205
We show that the Schrödinger propagator can be expanded in terms of resonances at energy levels at which a barrier separates the interaction region from infinity. The expansions hold for all times with errors small in the semi-classical parameter. As a byproduct we obtain a result on the approximation of clusters of resonant states by clusters of eigenfunctions of a self-adjoint reference operator. 相似文献
930.
Keiko OkuzumiNoriyuki Hara Yoshinori Fujimoto Junko YamadaAtsuko Nakamura Kyoko TakahashiMasuo Morisaki 《Tetrahedron letters》2003,44(2):323-326
Feeding studies of six 13C-labeled sterols, including clerosterol, to hairy roots of Ajugareptans var. atropurpurea have established that clerosterol is a precursor of three phytoecdysteroids, cyasterone, isocyasterone and 29-norcyasterone. 相似文献