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91.
92.
Nobuhiro Kodama Kiyoaki Tanaka Taizo Utsunomiya Yoshio Hoshino Fumiyuki Marumo Nobuo Ishizawa Masanori Kato 《Solid State Ionics》1984,14(1):17-24
Integrated intensities of X-ray reflections from a barium chloride fluoride single crystal were measured at 24, 180, 289, 402, 467 and 610°C. The intensities were used for the determination of the anharmonic potential parameters up to the third order. Harmonic potential parameters for each ion were obtained from the temperature dependence of thermal parameters, and anharmonic potential parameters were determined by the least-squares procedures, utilizing the temperature factor formalism based on the cumulant expansion. As a result, it has been found that the Ba2+ and Cl? ions show an anharmonicity, while no significant anharmonic effect was detected for the F? ion. From the potential calculated around the Cl? and F? ions, it was found that both Cl? and F? ions diffuse more easily within the (001) plane than along the c axis. 相似文献
93.
3-Chloro-2,5-dimethylpyrazine 1-oxide underwent cross-coupling with dialkylzinc reagents forming 3-alkyl-2,5-dimethylpyrazine 1-oxides. The reaction was realized by catalytic 1,3-bis(diphenylphosphino)-propane nickel(II) chloride and the optimum results were examined. 相似文献
94.
Katsuyuki Ogura Kazuo Ohtsuki Masami Nakamura Nobuhiro Yahata Kazumasa Takahashi Hirotada Iida 《Tetrahedron letters》1985,26(20):2455-2458
Methylthiomethyl p-tolyl sulfone (1) was conveniently alkylated to give mono- and dialkylated products (2 and 4). Reaction conditions for the trasformation of 2 and 4 into aldehydes (3) and ketones (5), respectively, were exploited. 相似文献
95.
Iwami Higashi Nobuhiro Shiotani M. Uda Tadashi Mizoguchi Hiroaki Katoh 《Journal of solid state chemistry》1981,36(2):225-233
The crystal structure of Mg51Zn20, a phase designated conventionally as “Mg7Zn3,” has been determined by the single-crystal X-ray diffraction method. It was solved by the examination of a Patterson synthesis, and refined by the ordinary Fourier and least-squares method; the R value obtained was 4.8% for 1167 observed reflections. The crystal is orthorhombic, space group Immm, with a = 14.083(3), b = 14.486(3), c = 14.025(3) Å, and Z = 2. There are 18 independent atomic sites, Zn1Zn6, Mg1Mg10, A, and B, and the last two sites are statistically occupied by Zn and Mg atoms with the occupancies; 0.46(2)Zn7 + 0.52(2)Mg11 and 0.24(2)Zn8 + 0.74(2)Mg12, for A and B, respectively. The structure of the crystal is described as an arrangement of icosahedral coordination polyhedra, to which all the atomic sites but Zn3 site belong. In this arrangement the Zn atoms other than the Zn3 and Zn8(B) center the icosahedral coordination polyhedra with coordination number 12. The Zn3, Zn8 atoms, and all the Mg atoms except Mg11(A) are located at the centers of various coordination polyhedra with the coordination numbers from 11 to 15. The distances between neighboring atoms are 2.71–3.07, 2.82–3.65, and 2.60–3.20 Å for ZnZn, MgMg, and ZnMg, respectively. 相似文献
96.
97.
98.
Pd/ZnO and Pt/ZnO exhibited anomalously high selectivity for the steam reforming of methanol, when PdZn and PtZn alloys phases were developed. The selectivity decreased over the catalysts having metal phases. 相似文献
99.
A new finite element technique for the analysis of wave run-up is presented in this paper. In this finite element approach, the movement of the shoreline is expressed by that of the nodal points at the wave front, and an auto mesh generation technique is effectively used. The present method is tested by the comparison with the experimental result of a channel with uniform slope, and two numerical examples are reported to show the efficiency of this method. As a final example, the tsunami run-up caused by the 1983 Nihonkai-Chubu earthquake is analysed and compared with actual records of the flooded area. 相似文献
100.
Mehata MS Iimori T Yoshizawa T Ohta N 《The journal of physical chemistry. A》2006,110(38):10985-10991
Stark absorption spectroscopy was applied to 6-hydroxyquinoline (6-HQ) doped in polymer films of poly(methyl methacrylate) (PMMA) and poly(vinyl alcohol) (PVA) at temperatures of 50-300 K. The electroabsorption (E-A) spectrum of 6-HQ markedly depends on temperature in a PMMA film. The polarization dependence as well as the temperature dependence of the E-A spectra reveals that 6-HQ is oriented along the direction of the applied electric field at room temperature in a PMMA film. As the temperature becomes lower, the field-induced orientation of 6-HQ is restricted, and only the Stark shift induced by a change in electric dipole moment and in molecular polarizability is observed. On the other hand, E-A spectra of 6-HQ doped in a PVA film are essentially independent of temperature, suggesting that 6-HQ is not oriented along the electric field even at room temperature in PVA. These results show that the molecular motion of 6-HQ in a polymer film is very sensitive to the microenvironment of the surrounding matrix. 相似文献