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991.
992.
Blaize S Gesuele F Stefanon I Bruyant A Lérondel G Royer P Martin B Morand A Benech P Fedeli JM 《Optics letters》2010,35(19):3168-3170
We report on the real-space observation of resonant frequency splitting in a high-Q waveguide-coupled silicon-on-insulator microdisk resonator. Phase sensitive near-field analysis reveals the stationary nature of the two resonant states, and spectral investigations clearly show their orthogonality. These measurements emphasize the role of the coupling waveguide in this splitting phenomenon. The symmetry of the two stationary whispering gallery modes is clearly observed and is found to follow the axial symmetry of the waveguide-coupled microdisk as it has been reported by earlier theoretical predictions. 相似文献
993.
Stéphane Métens Sébastien Villain Pierre Borckmans 《Physica D: Nonlinear Phenomena》2010,239(11):857-8472
We present a formalism which describes the spatio-temporal evolution of a gel submitted to an autocatalytic chemical reaction to which it is responsive. This theory is based on an extension of a hydrodynamical multi-diffusional approach of the gel dynamics, which is plunged into a chemically active mixture. Emergent and autonomous volume self-oscillation dynamics of the gel are obtained from the nonlinear coupling of the elastic deformation, the chemical kinetics and the transport phenomena, that take place in the system. We apply this formalism to a spherical bead of gel plunged in a Belouzov-Zhabotinsky oscillatory chemical reaction, for which Yoshida et al. have obtained numerous experimental results. The case of a gel immersed in an autocatalytic bistable chemical reaction is also considered. We show that such formalism describes the autonomous volume self-oscillation dynamics of the gel beads. 相似文献
994.
Hermann RP Keppens V Bonville P Nolas GS Grandjean F Long GJ Christen HM Chakoumakos BC Sales BC Mandrus D 《Physical review letters》2006,97(1):017401
M?ssbauer-effect and microwave absorption experimental evidence unambiguously demonstrates the presence of slow, approximately 450 MHz, tunneling of magnetic europium between four equivalent sites in Eu8Ga16Ge30, a stoichiometric clathrate. Remarkably, six of the eight europium atoms, or 11% of the constituents in this solid, tunnel between these four sites separated by 0.55 A. The off centering of the atoms or ions in crystalline clathrates appears to be a promising route for producing Rabi oscillators in solid-state materials. 相似文献
995.
We show that light (approximately or = 1-30 MeV) dark matter particles can play a significant role in core-collapse supernovae, if they have relatively large annihilation and scattering cross sections, as compared to neutrinos. We find that if such particles are lighter than approximately or = 10 MeV and reproduce the observed dark matter relic density, supernovae would cool on a much longer time scale and would emit neutrinos with significantly smaller energies than in the standard scenario, in disagreement with observations. This constraint may be avoided, however, in certain situations for which the neutrino-dark-matter scattering cross sections remain comparatively small. 相似文献
996.
997.
998.
Denis Billaud Dominique Begin Pierre Mirebeau 《Molecular Crystals and Liquid Crystals》2013,570(1-4):211-214
Cyclic voltammetry has been applied to study the reversibility of the oxidation of polyacetylene in sulfuric acid solutions and in lithium salts - nitromethane solutions. The intensity-potential curves indicate generally two steps of oxidation : the first one, corresponding to the doping, is reversible and is characterized by a dramatic increase of the electrical conductivity; the second one, called overoxidation, is due to the irreversible destruction of the carbon-carbon double bonds by formation of sp3 carbon atoms and is evidenced by the lowering of the conductivity. 相似文献
999.
1000.
Pierre Antoine Grillet 《代数通讯》2013,41(2):558-573
A construction is given for semigroups S such that S 3 has just two elements. 相似文献