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Iman Evazzade Mahmood Rezaee Roknabadi Mohammad Behdani Fatemeh Moosavi Daxing Xiong Kun Zhou Sergey V. Dmitriev 《The European Physical Journal B - Condensed Matter and Complex Systems》2018,91(7):163
We numerically analyze the interaction of small-amplitude phonon waves with standing gap discrete breather (DB) in strained graphene. To make the system support gap DB, strain is applied to create a gap in the phonon spectrum. We only focus on the in-plane phonons and DB, so the issue is investigated under a quasi-one-dimensional setup. It is found that, for the longitudinal sound waves having frequencies below 6 THz, DB is transparent and thus no radiation of energy from DB takes place; whereas for those sound waves with higher frequencies within the acoustic (optical) phonon band, phonon is mainly transmitted (reflected) by DB, and concomitantly, DB radiates its energy when interacting with phonons. The latter case is supported by the fact that, the sum of the transmitted and reflected phonon energy densities is noticeably higher than that of the incident wave. Our results here may provide insight into energy transport in graphene when the spatially localized nonlinear vibration modes are presented. 相似文献
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Microstructural and chemical changes in a NiO-YSZ electrocatalytic electrode were studied. The microstructural changes in the NiO-YSZ electrocatalytic electrode after the cell operation was compared with the electrode quenched under the applied voltage to suppress the oxidation process. The reversible reduction of NiO into Ni and the formation of intergranular Ni layers at the NiO/YSZ interface were investigated. It was shown that in a compositional range of the NiO-YSZ electrodes from 1/3 to 2/3 the value of the ambipolar conductivity increased with increasing voltage applied to the electrochemical cell. The observed reversible increase in the value of ambipolar conductivity of the electrocatalytic electrode is described in frames of the model of reversible reduction of NiO into Ni under the conditions of cell operation. 相似文献
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We show in the framework of the 1D nonlinear Schr?dinger equation that the value of the refraction angle of a fundamental soliton beam passing through an optical lattice can be controlled by adjusting either the shape of an individual waveguide or the relative positions of the waveguides. In the case of the shallow refractive index modulation, we develop a general approach for the calculation of the refraction angle change. The shape of a single waveguide crucially affects the refraction direction due to the appearance of a structural form factor in the expression for the density of emitted waves. For a lattice of scatterers, wave-soliton interference inside the lattice leads to the appearance of an additional geometric form factor. As a result, the soliton refraction is more pronounced for the disordered lattices than for the periodic ones. 相似文献
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The origin of the anomalously large value of the heat capacity of liquid water is discussed. Comparing the temperature dependence of the heat capacities for water with those for argon and hydrogen sulfide, we separate contributions of the translational and rotational degrees of freedom. The residual part is considered as being caused by the specific contributions of the transversal vibrations of H-bonds. The estimate for the number of H-bonds per molecule is obtained from the analysis of this contribution. This estimate is in quite good agreement with the estimates which follow from the analysis of the specific volume, heat of evaporation, and kinematic shear viscosity. 相似文献
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Abstract The effect has been studied of additive coloring on the magnitude of ion conductivity of RbAg4I5 crystals. It has been found that slight changes of silver stoichiometry of 10?3 at.% can lead to considerable variations of the ionic conductivity Δ[sgrave]i/[sgrave]i ? 0.1. The dependence has been observed of the magnitude of ion conductivity on the ratio between the integral intensities of the main bands in the photoluminescence spectrum of the γ-phase of RbAg4I5 which associated with the luminescence centres containing vacancies and interstitials of silver cations. 相似文献
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The energy of superfluid turbulence without the normal fluid is studied numerically under the vortex filament model. Time evolution of the Taylor-Green vortex is calculated under the full nonlocal Biot-Savart law. It is shown that for k<2pi/l the energy spectrum is very similar to the Kolmogorov's -5/3 law which is the most important statistical property of the conventional turbulence, where k is the wave number of the Fourier component of the velocity field and l is the average intervortex spacing. The vortex length distribution converges to a scaling property reflecting the self-similarity of the tangle. 相似文献