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991.
Local and nonlocal coercive estimates in Lebesgue, Hölder, and Morrey–Campanato spaces are proved for solutions of linear stationary systems of hydrodynamic type. For this purpose, the technique proposed by Italian mathematicians for the study of solutions to equations and systems of elliptic and parabolic types is developed. Bibliography: 14 titles. 相似文献
992.
S. Tavazzi A. Borghesi M. Campione A. Papagni A. Sassella P. Spearman 《Journal of luminescence》2004,110(4):212-216
We examine absorption of light in quaterthiophene crystals for different directions of the ray and wave-normal vector after refraction on the vacuum/crystal interface. Experimental non-normal incidence spectra are reported where different absorption bands show different behaviour as a function of the angle of incidence. This allows to identify those originating from the bu Frenkel exciton state. 相似文献
993.
Anti-BZ-Structure in Effect Algebras 总被引:1,自引:0,他引:1
The definitions of sharply approximating effect algebras, anti-BZ-effect algebras, central approximating effect algebras, and S-anti-BZ-effect algebras are given, the relationships between sharply approximating effect algebras and anti-BZ-effect algebras, between central approximating effect algebras and anti-BZ-effect algebras are established, and the set of anti-BZ-sharp elements in S-anti-BZ-effect algebras is proved to be an orthomodular lattice. 相似文献
994.
The mechanism of transition of a Bose gas to the superfluid state via thermal fluctuations under the condition of external cooling at a temperature above the transition point is considered. The probability of formation of such critical fluctuations (instantons) is calculated; it is found that this probability increases as the system approaches the transition temperature. It is shown that the evolution of an individual instanton is impossible without the formation of vortices in its superfluid part. 相似文献
995.
996.
The dynamic structure factors (DSFs) of several strong glasses (SF6, SF10, BK7, SUPRASIL) measured by Brillouin light scattering spectroscopy are reported. Spectra have been collected, at and above room temperature, at two scattering angles, θ=90° and θ=180° corresponding to exchanged wavevector q values ranging from 0.0256 to 0.0448 nm−1. In particular we find that the isotropic spectral lineshapes are in all cases well described by the simple hydrodynamic theory of an amorphous solid. The width of the Brillouin peaks are found to be consistent with the predicted q2 dependence at both investigated temperatures. This damping is however found to account only partially for the strong asymmetry of the Brillouin line clearly visible on a logarithmic intensity scale. As a matter of fact there is an excess intensity in the very low frequency plateau underlying the central component. The height of this plateau and hence the entire lineshape is well reproduced if a relaxation process is taken into account in the hydrodynamic equations. Owing to the intense elastic scattering we are able to determine unambiguously only the ratio between amplitude and characteristic time of this process which quantifies the sound dispersion to be of the order of a few percent in all samples. The temperature dependence of the parameters indicates that this relaxation cannot be attributed to thermally activated relaxation phenomena. These general findings favorably compare with molecular dynamics simulation results on similar systems. 相似文献
997.
The Clauser–Horne approach used to derive experimentally measurable quantities for performing experiments on EPR paradox based on Type-I Spontaneous Parametric Down Conversion (SPDC) sources is discussed. It is proved that in this case the deduced Bell's type inequality does not correctly express separability and causality. A deeper analysis of the problem shows that the Clauser–Horne hypothesis of factorizability of joint detection probability cannot be considered so general as to describe this physical situation. 相似文献
998.
The results of investigations of the rheological characteristics and electrical resistance of the suspensions of carbon black in vaseline oil under the effects of shear and vibration were presented. The investigations are carried out on an original unit that allowed one to simultaneously subject the suspensions to shear deformation and orthogonal vibration. The electrical resistance was also measured in an ac pulsed low-voltage mode. Possible mechanisms of the suspension conductivity were considered depending on the regime of dynamic action. 相似文献
999.
Feel like writing a review for The Mathematical Intelligencer? You are welcome to submit an unsolicited review of a book of your choice; or, if you would welcome being assigned a book to review, please write us, telling us your expertise and your predilections. 相似文献
1000.
A. P. Katchalov 《Journal of Mathematical Sciences》2005,127(6):2374-2388
Relationships between Gaussian beams and geometry are considered in the paper. We show that the main properties of the Gaussian beam solutions are determined by the natural geometry related to the problem under consideration. The geometry is determined by the Hamilton-Jacobi equation and the corresponding Hamiltonian. In particular, we find a geometric interpretation of the Riccati equation for the quadratic form of the phase function corresponding to a Gaussian beam in the case of Finsler geometry. Bibliography: 2 titles.__________Translated from Zapiski Nauchnykh Seminarov POMI, Vol. 297, 2003, pp. 66–92. 相似文献