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991.
The corrugation stability of the flat surface of a fast magnetohydrodynamic shock wave in a perfect monoatomic gas with a
constant heat capacity is studied with numerical techniques. The magnetic field makes an arbitrary angle with the plane of
discontinuity. It is shown that the shock wave remains stable only if it is strictly perpendicular to the magnetic field.
At any other angle between the fast shock wave and magnetic field, the former may spontaneously radiate outwardly propagating
magnetohydrodynamic waves under certain conditions. Incoming flow characteristics at which these waves are induced are determined. 相似文献
992.
Sylvia Pulmannová 《International Journal of Theoretical Physics》2003,42(5):907-919
Tensor products of quantum logics and effect algebras with some known problems are reviewed. It is noticed that although tensor products of effect algebras having at least one state exist, in the category of complex Hilbert space effect algebras similar problems as with tensor products of projection lattices occur. Nevertheless, if one of the two coupled physical systems is classical, tensor product exists and can be considered as a Boolean power. Some applications of tensor products (in the form of Boolean powers) to quantum measurements are reviewed. 相似文献
993.
§ 1 IntroductionInthispaperwediscusstheglobalclassicalsolutionofamultidimensionalquasistationaryproblem .Theproblemcomesfromthediscussionofagrowthmodelofselfmaintainingprotocell(see [1— 3])inmultidimensionalcase .Theprotocellcanbevisualizedashavingaporousst… 相似文献
994.
The reasons for the existence of various scenarios for structural transformations in disordered condensed media, such as liquids and amorphous substances, where both smeared transformations and sharp first-order transitions may occur, were analyzed. The ratio between the spatial scale of structural correlations and the size of the smallest possible region occupied by a new phase in the matrix of initial modification is the key parameter determining the scenario for equilibrium phase transformations in liquids. In amorphous substances, the experimentally observed transformations occur far from equilibrium, and the possible size of the region occupied by the new phase corresponds to the minimal nucleus size. For some amorphous solids, quantitative analysis of the transformation width was carried out and the main classes of covalent substances, in which the smeared or sharp transitions occur, were revealed. Specific features of the interparticle interactions determining various transformation scenarios are discussed. 相似文献
995.
Toshiyuki Sugawa 《Monatshefte für Mathematik》2003,139(1):61-68
The inner radius of univalence of a domain D with Poincaré density ρ
D
is the possible largest number σ such that the condition ∥ S
f
∥
D
= sup
w∈ D
ρ
D
(w)
−2∥ S
f
(z) ∥ ≤ σ implies univalence of f for a nonconstant meromorphic function f on D, where S
f
is the Schwarzian derivative of f. In this note, we give a lower bound of the inner radius of univalence for strongly starlike domains of order α in terms
of the order α.
The author was partially supported by the Ministry of Education, Grant-in-Aid for Encouragement of Young Scientists, 11740088.
A part of this work was carried out during his visit to the University of Helsinki under the exchange programme of scientists
between the Academy of Finland and the JSPS.
Received November 26, 2001; in revised form September 24, 2002
Published online May 9, 2003 相似文献
996.
V. A. Bednyakov 《Physics of Atomic Nuclei》2003,66(3):490-493
One can expect accessible lower bounds for the dark matter detection rate due to restrictions on masses of the SUSY partners. To explore this correlation, one needs a new-generation large-mass detector. The absolute lower bound for the detection rate can naturally be due to spin-dependent interaction. Aimed at detecting dark matter with sensitivity higher than 10?5 event/kg/d, an experiment should have a nonzero-spin target. Perhaps, it is best to create a GENIUS-like detector with both 73Ge (high spin) and 76Ge nuclei. 相似文献
997.
998.
999.
A pseudopotential depending on an effective core radius is proposed to study the binding energy, equation of state, ion-ion
interaction, phonon dispersion curves (q-space and r-space analysis), mode Grüneisen parameters and dynamical elastic constants
of some fcc f-shell metals La, Yb, Ce and Th. The contribution of the s-like electrons is calculated in the second-order perturbation
theory for the potential while d and f-like electron is taken into account by introducing repulsive short-range Born-Mayer
term. The parameter of the potential is evaluated by zero pressure condition. An excellent agreement between theoretical investigations
and experimental findings is achieved which confirms the present formalism 相似文献
1000.
I. El-Kady R. Biswas Y. Ye M. F. Su I. Puscasu Martin Pralle E. A. Johnson J. Daly A. Greenwald 《Photonics and Nanostructures》2003,1(1):69-77
In this work, we present both the theoretical basis as well as supporting experimental measurements for development of a novel mid-infrared thermally stimulated narrow band emitter with a spectral bandwidth of less than 10%. To achieve this, we utilize a metallized-surface 2D photonic crystal of air voids in a silicon background with hexagonal structure symmetry. Our results are based on the generation of discrete surface plasmon (SP) modes in the thin metallized layer residing on the top surface. This yields a series of adequately spaced discrete peaks in the reflection spectrum, dominated by a single sharp feature corresponding to the lowest plasmon order, in an otherwise uniform highly reflective spectrum (>90%) over most of the IR spectrum. This, in turn, gives rise to a sharp absorption feature with a correspondingly narrow thermal emission peak in the emission spectrum. Transfer matrix calculations simulate well both the position and strengths of the absorption peaks. By altering the period of the surface photonic lattice, the SP peak and emissive band can be tuned to the desired wavelength. These devices promise a new class of tunable infrared emitters with high power in a narrow spectral bandwidth. Such narrow band sources are critical to achieving high efficiency gas sensors. 相似文献