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1.
Waveguide propagation of intense electromagnetic radiation in slightly inhomogeneous nonlinear media
The propagation of self-localizing beams of electromagnetic waves in the form of nonlinear waveguides in a slightly inhomogeneous medium is studied analytically and numerically. The trajectories of the axial ray are studied as a function of its direction and the field strength at the initial point on the basis of a nonlinear scalar Helmholtz equation. Analytic expressions are derived. The longitudinal refractive index, the field intensity, and the waveguide radius are plotted as functions of the instantaneous position of the point on the axial ray. Deep penetration of the beam into the opaque region and the position of the screening surface are studied as functions of the parameters of the beam and the medium. A steady-state 3D problem is analyzed for a power-law nonlinearity with an arbitrary power. A 2D problem is analyzed for the case of a ponderomotive nonlinearity with saturation. 相似文献
2.
A. P. Mikhailovskaya N. E. Serova M. S. Kalugina A. M. Kiselev 《Russian Journal of Applied Chemistry》2014,87(1):108-113
The effect of quaternary ammonium salts on batch dyeing of cellulose materials with active dyes was examined. The use of benzyldimethylhexadecylammonium chloride and benzyldimethyldodecylammonium bromide as intensifi ers in dyeing of cellulose textile materials with active dyes of vinyl sulfone and monochlorotriazine types allows high intensity and durability of the color to be attained owing to increased degree of covalent fi xation of the dyes and their decreased desorption in the course of washing of the dyed material. 相似文献
3.
Z. A. Mikhailovskaya E. S. Buyanova S. A. Petrova V. M. Zhukovskii 《Russian Journal of Electrochemistry》2013,49(7):658-664
The possibility of synthesizing oxygen-ionic conductors from substituted bismuth molybdates containing [Bi12O14] n 8n+ columns, MoO4 tetrahedra, and isolated Bi ions in their structure was studied. The specifics of their structure and electric conductivity were investigated. The general formula of the solid solutions can be recorded as Bi13Mo5 ? x Me x O34 ? δ, where Me is the fouror five-valent d metal (Ti, Zr, V, Nb). The electric conductivity of doped bismuth molybdates considerably increased compared with that of the matrix compound. The electric conductivity reached 5.5 × 10?3 S cm?1 at 700°C and 1.8 × 10?4 S cm?1 at 350°C for the zirconium-doped compound with x = 0.4. The porosity of the ceramics was less than 5%; the thermal expansion coefficient was of the order of 14 × 10?6 K?1. Based on the set of their characteristics, these compounds are recommended as materials for membranes of electrochemical devices. 相似文献
4.
Klimova A. V. Mikhailovskaya Z. A. Buyanova E. S. Petrova S. A. 《Russian Journal of Electrochemistry》2021,57(8):825-832
Russian Journal of Electrochemistry - The possibility of synthesizing oxygen-ion conductors based on bismuth molybdate with antimony and tin substituted to the molybdenum sublattice is studied and... 相似文献
5.
Doklady Mathematics - 相似文献
6.
E. S. Buyanova Z. A. Mikhailovskaya Yu. V. Emel’yanova A. A. Levina M. V. Morozova S. A. Petrova N. V. Tarakina 《Russian Journal of Inorganic Chemistry》2017,62(2):211-217
Solid solutions LaNb1–x W x O4 + δ (x = 0.02–0.10, Δx = 0.02) were investigated, which crystallize in the monoclinic system (space group I2/c) at room temperature and undergo a phase transition into the tetragonal modification with increasing temperature. The stability of various modifications was analyzed by high-temperature X-ray powder diffraction analysis. The electrical conductivity of sintered samples was studied by impedance spectroscopy. Insertion of tungsten into the niobium sublattice leads to an increase in the conductivity of the solid solutions. 相似文献
7.
Odysseas Paschos Alexander N. Simonov Alesya N. Bobrovskaya Moritz Hantel Matthias Rzepka Petra Dotzauer Anton N. Popov Pavel A. Simonov Valentin N. Parmon Ulrich Stimming 《Electrochemistry communications》2010,12(11):1490-1492
The electrocatalytic activity of bimetallic BiPd catalysts supported on Sibunit carbon towards hydrogen oxidation/evolution reactions (HOR/HER) was studied in a gas diffusion electrode (GDE) setup. Catalysts were synthesized by deposition of Pd on the carbon support, followed by impregnation of Pd/C precursor with Bi(NO3)3 solution and reduction in hydrogen. Transmission electron microscopy and local EDX elemental analysis revealed that BiPd/C catalysts contain bimetallic particles with narrow size distribution with maxima at 3.2–4.1 nm. X-ray diffraction evidenced that bimetallic particles are constituted by Pd–Bi solid solution. It was shown that modification of Pd/C by bismuth increases the specific activity of palladium towards HOR/HER by a factor of 3. 相似文献
8.
The reaction of methyl o-(2-R-ethynyl)benzoates with hydrazine affords either fused 4-R-methylphthalazin-1-ones or 2-amino-3-R-methylideneisoindolin-1-ones.
The latter are on treatment with KOH undergo recyclization into the corresponding 4-R-methylphthalazin-1-ones. 相似文献
9.
The diffraction of light by ultrasound in an isotropic medium at arbitrarily small angles of incidence onto the acoustic layer
is calculated. The intermediate regime of diffraction is considered, for which the conditions of observation of the Raman-Nath
and Bragg diffraction are not satisfied in terms of the wave parameter. The effect of the acoustooptical interaction length
and angle between the incident light beam and the acoustic wave on the light intensity distribution over the diffraction peaks
is studied as a function of the acoustic power. Specific features of the transition from the Raman-Nath to the Bragg diffraction
regime through the intermediate regime of diffraction are analyzed. 相似文献
10.
E. S. Buyanova M. V. Morozova Yu. V. Emel’yanova Z. A. Mikhailovskaya S. A. Petrova R. G. Zakharov N. V. Tarakina V. M. Zhukovskii 《Russian Journal of Inorganic Chemistry》2011,56(12):1853-1857
This work continues the search for optimal preparation methods and studies of structural and transport characteristics of
BICUTIVOX solid solutions of the general composition Bi4V2 − x
Cu
x/2Ti
x/2O11 − δ (x = 0.0−0.35). 相似文献