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41.
Vyaselev O Arai K Kobayashi K Yamazaki J Kodama K Takigawa M Hanawa M Hiroi Z 《Physical review letters》2002,89(1):017001
We report Cd nuclear magnetic resonance (NMR) and Re nuclear quadrupole resonance (NQR) studies on Cd(2)Re(2)O(7), the first superconductor among pyrochlore oxides (T(c) approximately 1 K). The Re NQR spectrum at zero magnetic field below 100 K rules out any magnetic or charge order. The spin-lattice relaxation rate below T(c) exhibits a pronounced coherence peak and follows the weak-coupling BCS theory with nearly isotropic energy gap. The results of Cd NMR point to a moderate ferromagnetic enhancement at high temperatures followed by a rapid decrease of the density of states below the structural transition temperature of 200 K. 相似文献
42.
Optimal allocation of amplifiers in a dispersion-managed line for a wavelength-division-multiplexed soliton transmission system 总被引:1,自引:0,他引:1
Optimal allocation of amplifiers in a dispersion-managed line is theoretically derived by means of minimizing the collision-induced frequency shift in a two-channel wavelength-division-multiplexed soliton transmission system. Almost complete cancellation of the frequency shift can be obtained for such a system with any strength of dispersion management. 相似文献
43.
Toshie Tahara Yoshitsugu Sakuda Mitsuaki Kodama Yoshimasa Fukazawa Shô Itô Kazuyoshi Kawazu Shuhei Nakajima 《Tetrahedron letters》1980,21(19):1861-1862
The structures of xantholides A and B were deduced on the basis of IR and NMR spectra, and confirmed by X-ray analysis. Xantholide A inhibited the larval growth of Drosophila melanogaster. 相似文献
44.
A model calculation of resonance Raman scattering tensors has been carried out for a diatomic molecule with a harmonic potential for the ground state and a linear repulsive potential for the excited state. Expressions for scattering tensors have been obtained by using a series of recurrence formulas induced from the Green function of the nuclear hamiltonian of the repulsive potential of the excited state and nuclear wavefunctions for the harmonic potential. The relative scattering intensities of overtones depend on the gradient of the repulsive potential curve and are interpreted in terms of the overlap integrals between nuclear wavefunctions of upper and lower states. 相似文献
45.
Tetsuo Kodama 《Archiv der Mathematik》1971,22(1):271-274
Ohne ZusammenfassungThe author acknowledges support received from the National Research Council of Canada, Grant A-7210.Herrn. Prof. E.Lamprecht und Herrn Dr. H.Mathieu dankt Verfasser für ihre Anmerkungen, die zu Verbesserungen der ursprünglichen Fassung führten. 相似文献
46.
47.
We have examined the implosion of an indirectly driven reentrant-cone shell target to clarify the issues attendant on compressing fuel for a fast ignition target. The target design is the hydrodynamic equivalent of a NIF cryoignition target scaled to be driven by Omega. Implosions were imaged with backlit x radiographs and modeled with LASNEX. The simulations were generally in good agreement with the experiments with respect to the shell diameter, density, and symmetry, but did not show the prestagnation central absorption maximum. The existence of material between the original cone and the shell is sensitive to gold M-band radiation, which penetrates the shell and ablates gold from the cone. The simulated radiographs using recently measured M-band fractions showed absorption between the cone and shell similar to the experiment. This gold ablation might be a problem in a cryoignition target. 相似文献
48.
49.
Shimizu K Suzuki H Hayashi E Kodama T Tsuchiya Y Hagiwara H Kitayama Y 《Chemical communications (Cambridge, England)》2002,(10):1068-1069
Direct 1,4-conjugate addition of naked aldehydes to vinylketones is catalysed effectively by N-methyl-3-aminopropylated FSM-16 mesoporous silica, which can be regarded as a novel heterogeneous catalysis for a practical C-C bond formation reaction. 相似文献
50.
Takahashi K Kodama R Tanaka KA Hashimoto H Kato Y Mima K Weber FA Barbee TW Da Silva LB 《Physical review letters》2000,84(11):2405-2408
A laser self-focused channel formation into overdense plasmas was observed using a soft x-ray laser probe system with a grid image refractometry (GIR) technique. 1.053 &mgr;m laser light with a 100 ps pulse duration was focused onto a preformed plasma at an intensity of 2x10(17) W/cm (2). Cross sections of the channel were obtained which show a 30 &mgr;m diameter in overdense plasmas. The channel width in the overdense region was kept narrow as a result of self-focusing. Conically diverging density ridges were also observed along the channel, indicating a Mach cone created by a shock wave due to the supersonic propagation of the channel front. 相似文献