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891.
P. V. Kharitonskii A. M. Frolov V. S. Rudnev A. Yu. Ustinov I. V. Lukiyanchuk V. P. Morozova 《Bulletin of the Russian Academy of Sciences: Physics》2010,74(10):1404-1406
The magnetic properties of iron-containing coatings formed on aluminum by plasma-electrolytic oxidation were investigated.
It was shown that the magnetic state of the samples studied is most likely induced by chemically inhomogeneous (multiphase)
ferromagnetic particles. 相似文献
892.
893.
E. N. Sergeev S. M. Grach G. P. Komrakov V. L. Frolov P. Stubbe B. Thide T. Leyser T. Carozzi 《Radiophysics and Quantum Electronics》1999,42(8):715-727
We present the results of experimental studies of the evolution of diagnostic stimulated electromagnetic emission of the ionosphere
(DSEE) in a broad range of the pump and probing wave frequencies under sounding of the F-layer disturbed by powerful HF radio
waves. We study the parameters of the overshoot effect in SEE evolution during the relaxation stage of artificial small-scale
irregularities and show that the amplification of DSEE (inverse overshoot effect) is related to the relaxation of the anomalous
attenuation due to scattering at these irregularities. We have found that the characteristic time scales of development of
the overshoot effect decrease and its value increases as the pump wave frequency decreases from 6 to 4 MHz and as the probed
volume moves from the edge to the central part of the disturbed volume. We relate the effects observed to the increasing intensity
of the irregularities with scales l∼∼3−10 m.
Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Radiofizika, Vol. 42, No. 8, pp. 810–824, August 1999. 相似文献
894.
The metal-semiconductor phase transition in vanadium sesquioxide is investigated by the acoustic emission method. It is shown that the acoustic emission in single crystals of this compound is due to thermoelastic stresses arising in the crystal upon the phase transition. Transformation of the acoustic emission activity and an increase in the phase transition temperature are revealed in the temperature cycling of the sample. Observation of peaks of the acoustic emission activity at a temperature of 5–6 K above the critical temperature indicates that crystal nuclei of the monoclinic phase appear in the high-temperature (trigonal) phase of the crystal. 相似文献
895.
M. B. Rzhevskii G. Kh. Cherches M. I. Kuz'menkov V. V. Pechkovskii Yu. Ya. Efimov Yu. I. Naberukhin I. A. Afonskaya V. N. Morozov O. V. Koryakova V. P. Zhukov A. Ya. Zapevalov L. A. Perelyaeva L. I. Burov V. M. Krylov A. M. Sarzhevskii Yu. L. Frolov V. B. Mantsivoda N. N. Chinanina G. G. Skvortsova V. N. Vinogradova M. I. Godneva 《Journal of Applied Spectroscopy》1976,25(4):1332-1334
896.
The bound state properties and general structure of some H+3-like molecular ions are determined from the results of direct numerical computations. All our calculations are performed with the use of non-adiabatic variational expansion written in the basis of five-body (= ten-dimensional) gaussoids. A large number of geometrical properties and expectation values of many inter-particle delta-functions are presented for the H2D+, H2T+, D2H+, D2T+, T2H+, T2D+ and HDT+ two-electron five-body ions. The problem of inter-particle correlations in five-body systems and related problem of adiabatic divergence in the H+3-like ions are also briefly discussed. 相似文献
897.
All iron ions in the Cu1 and Cu2 local lattice sites of the YBa2(Cu0.9 57Fe0.1)3O7.01 superconductor with T c=31 K experienced magnetic ordering below T m=22 K. Therefore, at T < T m, magnetic ordering coexisted with superconductivity. According to the Mössbauer spectroscopy data, iron ions in Cu2 (Fe2) sites were in the low-spin state at T < T m(S= 3/2 or 1/2), whereas an equal number of iron ions in Cu1 (Fe1) sites were in the high-spin Fe3+ state (S=5/2). The magnetic transition near T m changed iron ion spin states-low-spin ions turned into high-spin ions, and vice versa. This preserved the spin balance between iron ions in the Cu1 and Cu2 layers. Control measurements on other samples of the YBa2(Cu1? x Fex)3O7±δ series substantiated these conclusions. 相似文献
898.
A new discrete mathematical model of molecular shape is proposed, making use of the partition property of a representation of molecular shape. According to its geometrical and topological structure, a molecular surface can be partitioned into unbounded two-dimensional subsets (domains) and some common subsets of closures of two or more domains. The sets of these domains as a base of a finite topology, containing the Boolean n-cube as a lower Boolean sub-lattice of this topology, defines the domain of the proposed logical model. A logical function can be obtained that reflects the properties of the topological domains as well as the interrelations on the set of domains. Based on classical or quantum-chemical representations of molecular shape, these models allow one the implementation of methods of logical diagnostics in chemistry, and the definition of a metric on the set of molecular shape equivalence classes. The families of molecular shapes can be considered as sets of logical models. The proposed model is unified in the sense that the structures of differentiable and non-differentiable surfaces can be represented in the same mathematical framework. These logical models will also work for interpenetrations of the above types of surfaces. 相似文献
899.
V. F. Fedorov Yu. A. Frolov P. O. Shishkov 《Journal of Applied Mechanics and Technical Physics》2001,42(3):392-396
The paper reports results of recording the pulsed microwave radiation of return lightning strokes using a high–time–resolution, 8–mm–wavelength radiometer. The procedure of recording pulsed radiations with millimetric wavelength is briefly described. The complex shape of the recorded pulses is shown to be due to the features of the current system within the antenna spot at the initial stage of a lightning return stroke. 相似文献
900.
Okhotnikova Ekaterina S. Ganeeva Yulia M. Frolov Igor N. Firsin Aleksei A. Yusupova Tatiana N. 《Journal of Thermal Analysis and Calorimetry》2019,135(2):1243-1255
Journal of Thermal Analysis and Calorimetry - The thermo-physical properties enhancement of nanolubricants can improve the heat transfer performance in refrigeration system. In this study,... 相似文献