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21.
The possible formation of antihydrogen atoms via the collision of metastable antiprotonic helium atoms with positrons and
positroniums is discussed based on the known behavior of positrons in helium media. 相似文献
22.
23.
Akio Toshimitsu Toshiaki Aoai Hiroto Owada Sakae Uemura Masaya Okano 《Tetrahedron》1985,41(22):5301-5306
The reaction of phenylselenenyl chloride with olefins in aqueous acetonitrile affords β-hydroxyalkyl phenyl selenides in excellent yields, providing the most convenient method for hydroxyselenation of olefins so far reported. When the reaction was applied to conjugated dienes, monohydroxyselenated products were obtained in good to excellent yields. From non-conjugated dienes, on the other hand, cyclic ethers containing two phenylseleno groups were produced in good to excellent yields, the first step of this reaction being the hydroxyselenation of one double bond. 相似文献
24.
Toshimitsu Yamazaki 《Hyperfine Interactions》1997,104(1-4):3-13
The author traces the encounter of μSR physicists with the Kubo–Toyabe theory and the subsequent development of zero‐field
μSR by mutual communication between experiment and theory.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
25.
Toshimitsu Asakura 《Optical and Quantum Electronics》1970,2(3):115-123
The ensemble-averaged spatial coherence of quasi-thermal light, produced by passing a focused laser beam through a rotating ground glass plate, is studied as a function of the illuminated area, the fineness of the glass used, the speed of rotation of the glass, and the laser mode selected as a primary source. It becomes clear that the ensemble-averaged spatial coherence depends strongly upon the illuminated area and on the fineness of the rotating ground glass, and also on the laser mode chosen but not on the speed of rotation of the glass. 相似文献
26.
Treatment of several cyclic olefins, β-pinene, allylbenzene, and estragole with palladium(II) salt in acetic acid in the presence of t-butyl hydroperoxide and tellurium(IV) oxide afforded mainly the corresponding allylic acetates. The reaction proceeded catalytically with palladium(II) salt, t-BuOOH working as a reoxidizing agent. 相似文献
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29.
Takeda Y Kobayashi M Okane T Ohkochi T Okamoto J Saitoh Y Kobayashi K Yamagami H Fujimori A Tanaka A Okabayashi J Oshima M Ohya S Hai PN Tanaka M 《Physical review letters》2008,100(24):247202
The magnetic properties of as-grown Ga1-xMnxAs have been investigated by the systematic measurements of temperature and magnetic field dependent soft x-ray magnetic circular dichroism (XMCD). The intrinsic XMCD intensity at high temperatures obeys the Curie-Weiss law, but a residual spin magnetic moment appears already around 100 K, significantly above the Curie temperature (T_{C}), suggesting that short-range ferromagnetic correlations are developed above T_{C}. The present results also suggest that the antiferromagnetic interaction between the substitutional and interstitial Mn (Mn_{int}) ions exists and that the amount of the Mn_{int} affects T_{C}. 相似文献
30.
Na-Oki Ikenaga Tomonari Kiyomi Itaru Yonezawa Chieko Yukawa Toshimitsu Suzuki 《Research on Chemical Intermediates》2008,34(5-7):603-615
Hydrogenation reactions of alkenes (cyclohexene, ethyl acrylate, styrene and 1,5-cyclooctadiene) and aromatic compounds (o-, m- and p-xylene) were carried out in order to examine the activity of palladium-loaded surface-oxidized diamond (Pd/O-Dia) catalyst in liquid-phase hydrogenation. The catalytic performance was compared to commercial palladium-loaded activated carbon (Pd/C) catalyst. The catalyst activities were evaluated by conversions of reactants and H2 uptake rates in the early stage of the reaction. In all the hydrogenation reactions of alkenes and aromatic compounds, the activity of Pd/O-Dia was almost the same as or slightly higher than that of Pd/C. Dispersion of Pd metal was measured by a CO-pulsed adsorption technique and TEM observations of the catalysts. Pd dispersions were on the same order of magnitude according to the CO-pulsed adsorption technique, although the Pd/C catalyst had a higher surface area (718 m2/g) than that of Pd/O-Dia (23 m2/g). The Pd particle sizes on O-Dia measured by TEM observation were slightly smaller than those on the activated carbon. Such highly dispersed Pd particles on O-Dia would contribute to higher activity for the hydrogenation reaction of alkenes and aromatic compounds. 相似文献