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61.
The results are given of an investigation of the convective and radiative heat transfer at the leading critical point of a body in the flow of a radiating mixture of carbon dioxide and nitrogen, taking account of viscosity and thermal conductivity. The system of equations is written down under the assumption that the shock layer is thin, and its solution is obtained in the region between the body and the shock wave. It is assumed that there is local thermodynamic equilibrium throughout the compressed layer. The coefficients of absorption of the mixture are assumed to depend on the wavelength, the temperature, and the pressure. From the solution we determine the radiative and convective thermal fluxes at the wall, taking account of their interaction for temperatures behind the shock wave of 9000–12000 deg K and pressures of p=1 and 10 atm. By analyzing these results it is concluded that the effect of radiation on the convective heat transfer is insignificant, the effect being qualitatively different at large and small pressures. The fundamental contributions to the radiant thermal flux at the wall in the versions of the problem considered come from the following spectral interval: 0.128–0.33, where there is a fourth positive system of carbon monoxide bands (~43%), and 0.33–0.66, where there is an ultraviolet system of cyanogen (~40%). The contribution from the spectral interval 0.80–1.15 is ~20%. Only about 15% of the radiant energy comes from the comparatively large interval 0.45–0.80. As the pressure increases, the contribution from the ultraviolet part of the spectrum falls, and the contribution from the visible part of the spectrum increases.Translated from Izvestiya Akademii Nauk SSSR, Mekhanika Zhidkosti i Gaza, No. 2, pp. 39–47, March–April, 1971. 相似文献
62.
M. V. Karasev 《Russian Journal of Mathematical Physics》2010,17(2):207-217
For a generic quantum integrable system, we describe the asymptotics of the eigenstate density and of the trace of the evolution
operator in all orders of the quantization parameter. This is done by using quantum symplectic geometry, which makes the given
quantum system to be equivalent to a deformed classical system with arbitrary accuracy with respect to the quantization parameter.
The asymptotics is explicitly given via the deformed symplectic form, deformed Liouville-Arnold tori, and deformed Maslov
class. 相似文献
63.
In this paper we compute: the Schwarz genus of the Stiefel manifold Vk(Rn) with respect to the action of the Weyl group Wk:=(Z/2)k?Sk, and the Lusternik–Schnirelmann category of the quotient space Vk(Rn)/Wk. Furthermore, these results are used in estimating the number of critically outscribed parallelotopes around a strictly convex body, and Birkhoff–James orthogonal bases of a normed finite dimensional vector space. 相似文献
64.
V. Yu. Karasev A. Yu. Ivanov E. S. Dzlieva A. I. Éĭkhval’d 《Journal of Experimental and Theoretical Physics》2008,106(2):399-403
Highly ordered three-dimensional dust structures are created in a striated glow discharge, and their horizontal cross-sectional images are analyzed. Calculated correlation functions, local correlation parameters, and corresponding approximations are used to classify the state of a structure according to the Kosterlitz-Thouless-Halperin-Nelson-Young (KTHNY) two-dimensional melting theory and a phenomenological approach. An orientational map based on an orientational parameter is proposed to expose domains in a cross section of a structure. It is shown that a plasma crystal is a polycrystal consisting of hexagonal domains (crystallites). Thermophoretic forces are used to create corners of various angles in the perimeter of the structure. Transition between hexagonal and square cell shapes is observed. 相似文献
65.
66.
A. V. Gerasimenko A. V. Polishchuk L. M. Volkova E. T. Karaseva V. E. Karasev 《Russian Journal of Coordination Chemistry》2008,34(1):8-13
Nalidixium tetrachloroantimonate monohydrate, (C12H13N2O3)SbCl4 · H2O, has been synthesized and its crystal structure has been determined. The structure is built of the [Sb2Cl8]2? anions, C12H13N2O 3 + nalidixium cations, and H2O molecules joint by hydrogen bonds and π-π-and Cl?Cl interactions. The [Sb2Cl8]2? anion is a dimer of the SbCl5 E distorted octahedra sharing common Cl?Cl edge (E is the lone electron pair). The Sb polyhedra contain two short Sb-Cl bonds (2.387 and 2.395 Å), one bond of a medium length (2.508 Å), and two long bridging bonds (2.745 and 3.054 Å). 相似文献
67.
Roman N. Karasev Edgardo Roldán-Pensado Pablo Soberón 《Israel Journal of Mathematics》2016,212(2):705-728
We study nested partitions of Rd obtained by successive cuts using hyperplanes with fixed directions. We establish the number of measures that can be split evenly simultaneously by taking a partition of this kind and then distributing the parts among k sets. This generalises classical necklace splitting results and their more recent high-dimensional versions. With similar methods we show that in the plane, for any t measures there is a path formed only by horizontal and vertical segments using at most t - 1 turns that splits them by half simultaneously, and optimal masspartitioning results for chessboard colourings of Rd using hyperplanes with fixed directions. 相似文献
68.
We describe how a top-like quantum Hamiltonian over a non-Lie algebra appears in the model of the planar Penning trap under the breaking of its axial symmetry (inclination of the magnetic field) and tuning parameters (electric voltage, magnetic field strength and inclination angle) at double resonance. For eigenvalues of the quantum non-Lie top, under a specific variation of the voltage on the trap electrode, there exists an avoided crossing effect and a corresponding effect of bilocalization of quantum states on pairs of closed trajectories belonging to common energy levels. This quantum tunneling happens on the symplectic leaves of the symmetry algebra, and hence it generates a tunneling of quantum states of the electron between the 3D-tori in the whole 6D-phase space. We present a geometric formula for the leading term of asymptotics of the tunnel energy-splitting in terms of symplectic area of membranes bounded by invariantly defined instantons. 相似文献
69.
Borodin V. G. Vatulin V. V. Zhidkov N. V. Elin I. P. Komarov V. M. Karasev V. V. Koltsov V. V. Malinov V. A. Migel V. M. Popikov V. S. Rimsky-Korsakov A. A. Suslov N. A. Charukhchev A. V. 《Physics of Atomic Nuclei》2019,82(12):1706-1713
Physics of Atomic Nuclei - The possibility of observing the stimulated de-excitation of nuclear isomers (SDENI) in plasma (plasma lifetime ∼1.5 ps, temperature of electrons ∼ 10 keV)... 相似文献
70.
Karasev V. Yu. Dzlieva E. S. Pavlov S. I. Novikov L. A. Mashek I. Ch. 《Technical Physics》2019,64(1):42-46
Technical Physics - Self-rotation (rotation about the center of mass) of dust particles in a magnetic field has been investigated. The angular velocity of self-rotation in a dust trap produced by... 相似文献