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271.
272.
O. V. Misochko K. Kisoda H. Harima K. Mizoguchi K. Sakai S. Nakashima 《Physica C: Superconductivity and its Applications》1999,320(3-4):213-217
We report an optical study of the superconducting transition in the YBa2Cu3O7−x films on MgO substrate carried out by femtosecond pump–probe spectroscopy. In both the normal and the superconducting state, we have observed the transient time-resolved reflectivity caused by the oscillations associated with two A1g metal-ion modes. Temporal interference between the modes is modified below the phase transition, which also appeared in an altered relative intensity of the modes in the Fourier transformed spectra. 相似文献
273.
274.
Yoshinori Kamiya Yasutoshi Naito Keishin Mizoguchi Katsuhiko Terada Johann Moreau 《Journal of Polymer Science.Polymer Physics》1997,35(7):1049-1053
The Flory–Huggins interaction parameters χ for 23 gases (He, Ne, Ar, Kr, Xe, H2, N2, O2, N2O, CO2, CH4, C2H4, C2H6, C3H6, C3H8, 1,3-C4H6, four C4H8's, n-C4H10, iso-C4H10, and n-C5H12) in five rubbery polymers (1,2-polybutadiene (PB), poly(ethylene-co-vinyl acetate)) (EVAc), polyethylene (PE), polypropylene (PP), and poly(dimethyl siloxane) (PDMS) were determined from either literature data on Henry's law coefficient and partial molar volume or those on sorptive dilation for each polymer/gas system. Values of χ for the gases increased in the order of PDMS < PP ≡ PB < EVAc ≡ PE. Among the gases except He and H2 whose χ values are not reliable, Ne and Xe have respectively the highest and the lowest values of χ for the polyolefins. The χ values of the hydrocarbons were compared together with previously reported χ values of n-alkanes C3-C10. The dependencies of χ upon concentration and temperature were discussed on the basis of the literature data. © 1997 John Wiley & Sons, Inc. J Polym Sci B: Polym Phys 35 : 1049–1053, 1997 相似文献
275.
Masahiro Takeda Tadaaki Hashimoto Takayoshi Fujii Shin Ono Toshiaki Yoshimura Choichiro Shimasaki Hiroyuki Morita 《Heteroatom Chemistry》1999,10(5):363-367
Previously, a facile formation of a thioaldehyde by the thermolysis of a heteroaryl phenacyl sulfoxide was confirmed by the detection of a cycloadduct with 2,3‐dimethyl‐1,3‐butadiene. The usefulness of benzothiazolyl phenacyl sulfoxide as a precursor for 2‐oxo‐2‐phenylethanethial was studied under the same conditions in the presence of various dienes and anthracene. In all cases, the Diels‐Alder cycloadducts were formed in moderate to good yields, and the addition of triethylamine as external base was revealed to be effective for carrying out the thermolysis under milder reaction conditions and for the improvement of yields. © 1999 John Wiley & Sons, Inc. Heteroatom Chem 10: 363–367, 1999 相似文献