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101.
A. A. Makarov 《Hyperfine Interactions》1987,37(1-4):49-70
Different problems of coherent quasi-resonant excitation of multilevel systems in monochromatic radiation fields are discussed.
Analytically solvable examples are presented, and, on this basis, some principal effects of cohrent multilevel dynamics are
treated. 相似文献
102.
V. V. Lukashov M. S. Makarov S. N. Makarova I. K. Igumenov 《Journal of Structural Chemistry》2017,58(8):1484-1492
We present results of the experimental study and numerical simulation of radiation-convective heat and mass transfer during the sublimation of spherical particles of metal β-diketonates in a high-temperature inert gas flow (argon or helium). The sublimation process is visualized, and experimental data on the temperature variation dynamics and particle size are obtained. It is shown that at stable transfer of the compound from the particle surface the sublimation proceeds with the formation of large pores in its structure. The effect of inert gas properties on the kinetics of the vaporization process of precursor particles with various initial diameters is analyzed in the temperature range from 200 °C to 330 °C. Due to a higher thermal conductivity and heat capacity of helium as compared with argon, the choice of helium as carrier gas causes an increase in the sublimation intensity. 相似文献
103.
A model of the physico-chemical kinetics of the reactions taking place behind the front of an intense shock wave propagating in air with a speed of 9–14 km/s is proposed. The problem of describing the chemical reactions, namely, molecular dissociation and exchange reactions involving vibrationally excited molecules in the absence of vibrational equilibrium, is solved. The vital role of the vibrational excitation delay in the dissociation of oxygen and nitrogen is established. The rate of the exchange reaction between nitrogen molecules and oxygen atoms in the shock wave depends only slightly on the vibrational excitation level. It is demonstrated that the rate constants for thermally nonequilibrium dissociation reactions can be represented within the framework of the one-temperature approximation at constant vibrational temperatures of the dissociating species satisfying quasi-stationary conditions.Moscow. Translated from Izvestiya Rossiiskoi Akademii Nauk, Mekhanika Zhidkosti i Gaza, No. 2, pp. 169–182, March–April, 1995. 相似文献
104.
T. Yu. Chemekova O. V. Avdeev S. S. Nagalyuk E. N. Mokhov Kh. Khelava Yu. N. Makarov 《Journal of Surface Investigation: X-ray, Synchrotron and Neutron Techniques》2011,5(6):1136-1139
Currently, wafers of aluminum nitride cut from bulk aluminum nitride crystals (AlN) grown by sublimation are considered promising
substrates for obtaining light-emitting diode structures based on nitrides of the third group. In this study, the structural
characteristics and electrical properties of AlN, as a prospective substrate material for light-emitting diode heterostructures
based on AlGaN/GaN, were investigated. The substrate working surface ((0001) plane, Al-polar) was specifically prepared for
epitaxial growth using chemical-mechanical polishing. The surface roughness (“epi-ready”), as estimated by atomic force microscopy,
did not exceed 0.3 nm. 相似文献
105.
S. P. Knurenko A. K. Makarov M. I. Pravdin A. V. Saburov 《Bulletin of the Russian Academy of Sciences: Physics》2011,75(3):291-293
Characteristics of the muon component in extensive air showers and the fluctuations of muons are considered. In this work,
we compare experimental data with computations performed for various models of the hadron interactions of protons and iron
nuclei. The aim of this analysis is to obtain information on the mass composition of cosmic rays in an ultra-high energy region. 相似文献
106.
E. K. Makarov 《Differential Equations》2014,50(10):1329-1335
We obtain sufficient conditions for a given class of piecewise continuous bounded perturbations to be a limit class, i.e., to admit the computation of the least upper bound for the exponents of linear differential systems with perturbations in that class by a formula similar to well-known formulas for the central and exponential exponents. 相似文献
107.
108.
We prove that on the Sobolev spaces HN0 H^N_0 (N S 0) of 1-periodic functions in HNloc (Bbb R) H^N_{loc} ({Bbb R}) with average 0, the Korteweg-deVries equation (KdV) admits global Birkhoff coordinates. 相似文献
109.
110.