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排序方式: 共有390条查询结果,搜索用时 76 毫秒
1.
Radiophysics and Quantum Electronics - The Wigner and Kirkwood functions are widely used for signal processing. We review their properties and representations. The Wigner function calculation... 相似文献
2.
A. Ya. Fridman A. Yu. Tsivadze E. M. Morozova N. P. Sokolova A. A. Shiryaev G. A. Petukhova A. M. Voloshchuk I. I. Bardyshev A. M. Gorbunov I. Ya. Polyakova A. K. Novikov V. N. Titova A. A. Yavich N. V. Petrova 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2016,90(12):2453-2458
A material with porous structures formed by jointed aza- and oxa-aza-crowns with peripheral OHgroups is synthesized on the basis of cellulose fabric and PVC transformed into hydroxyethylcyclam. Mesopores are mainly observed on the fiber surface. The specific surface of the material is 6 m2/g; the volume of free space is 0.112 cm3/g. Assuming the internal pores have a disk-like shape, their width is estimated at 2 nm. The material sorbs vapors of aliphatic and aromatic hydrocarbons, alcohols, aldehydes, ketones, amines, amides, nitriles, and sulfoxides. It also swells to a limited degree in organic solvents. When sulfuric acid or sodium hydroxide is sorbed in the pores, compounds of them with H+- and OH–-conducting systems of hydrogen bonds are formed. 相似文献
3.
Gorbunov M. A. Ilinskiy A.V. Pleshakova R. P. Tseitlin V. G. Shikanov A. E. Shkolnikov E. Ya. Yakovlev O. V. 《Physics of Atomic Nuclei》2021,84(11):1852-1855
Physics of Atomic Nuclei - The paper is devoted to the study of the influence of pulsed instability of neutron generation on the efficiency of small transportable HMCs. Experimental diagrams of the... 相似文献
4.
A liquid metal flow induced by a rotating magnetic field in a cylindrical container of finite height was investigated experimentally. It was demonstrated that the flow in a rotating magnetic field is similar to geophysical flows: the fluid rotates uniformly with depth and the Ekman layer exists at the container bottom. Near the vertical wall the flow is depicted in the form of a confined jet whose thickness determines the instability onset in a rotating magnetic field. It was shown that the critical Reynolds number can be found by using the jet velocity u
0 for Re
cr
=u
2
0/
u/
r. The effect of frequency of a magnetic field on the fluid flow was also studied. An approximate theoretical model is presented for describing the fluid flow in a uniform rotating magnetic field.List of Symbols
U
r
, U
, U
z
radial, azimuthal and vertical velocity components, respectively
-
B
r
, U
, B
z
radial, azimuthal and vertical magnetic induction components
-
A
vector potential of magnetic field
-
j
induced electric current density
-
electrical conductivity of fluid
-
electrical potential
-
kinematic viscosity
-
tf
electromagnetic volume force
-
angular velocity of fluid rotation
-
R
container radius
-
H
container height
-
aspect ratio
-
E
Ekman number
-
Re
cr
critical Reynolds number
-
r, z
radial and axial coordinates 相似文献
5.
Thermal gravity convection in a horizontal layer of compressible perfect gas heated from below and a van der Waals gas near the critical state is investigated. The characteristics of the isentropic equilibrium of a compressible medium with a van der Waals equation of state are considered. The known conditions of convection onset in the perfect and van der Waals gases are checked on the basis of a solution of the complete and linearized equations. The restrictions imposed in deriving the known formulas for the adiabatic temperature gradients used in the conditions of absence and onset of convection are discussed. The characteristics of the convective heat transfer are examined, including the causes of the heat-transfer deterioration in the near-critical medium above the hydrostatic equilibrium threshold. 相似文献
6.
Bubukin I. T. Agafonov M. I. Rakut’ I. V. Pankratov A. L. Yablokov A. A. Troitsky A. V. Priymak A. S. Gorbunov R. V. 《Radiophysics and Quantum Electronics》2019,62(7-8):562-569
Radiophysics and Quantum Electronics - We discuss the results of the atmospheric absorption studies on the territory of the Kara-Dag radio astronomy station in Crimea in the millimeter-wavelength... 相似文献
7.
8.
V. Grebenyuk V. Boreiko A. Dmitrotsa N. Gorbunov B. Khrenov P. Klimov M. Lavrova E. M. Popescu B. Sabirov A. Tkachenko L. Tkachev A. Volvach I. Yashin 《Physics of Particles and Nuclei Letters》2016,13(5):579-582
The purpose TUS space experiment is to study cosmic rays of ultrahigh energies produced by extensive air showers from space. The concentrator is located on satellite, made in the form of the Fresnel mirror towards the earth’s atmosphere, the focus of which is a photodetector. The angle of view of the mirror is ±4.5° that for a given height of the orbit corresponds to the area 80 × 80 km2 on ground. The ground complex consisting of a number of stations, to check the optical system of the experiment is created, (their location and the amount will be determined after the launch of the satellite based on its actual orbit). 相似文献
9.
Journal of Experimental and Theoretical Physics - We study the creation of high-energy SM particles in the Starobinsky model of dark energy (a variant of F(R)-gravity) inside the regions... 相似文献
10.
M. S. Denisov A. D. Antuf’eva A. A. Gorbunov K. O. Manylova V. A. Glushkov 《Russian Journal of General Chemistry》2015,85(12):2765-2770
Ferrocenol esters were prepared by the reaction of ferrocenylboric acid with aldehydes and air oxygen catalyzed by N-heterocyclic carbene. Optical properties (electron absorption and fluorescence spectra) and electrochemical behavior of the obtained compounds were studied (oxidation and reduction during the process of cyclic voltammetry). 相似文献