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31.
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33.
The modification of electrodiffusional method of the wall shear stress measurements is applied for registration of the Taylor
bubble shear stress in an upward liquid flow. Time realization of shear is considered as a structure frozen into the flow,
which moves together with a bubble. Experiments were carried out in laminar and transitional liquid flows. The wall shear
stress in the liquid film around bubble averaged over the tube perimeter is presented for different flow Reynolds numbers
and different lengths of the bubble. 相似文献
34.
V. S. Gorelik A. A. Ionin S. I. Kudryashov S. V. Makarov L. V. Seleznev D. V. Sinitsyn R. A. Chanieva A. R. Sharipov 《Bulletin of the Lebedev Physics Institute》2011,38(11):328-333
The prepared samples were characterized by reflection and transmission spectra of broadband visible-range radiation, and the
volume fraction of substances introduced into pores of artificial opals is estimated. It is found that the introduction of
solid-state nanoparticles with negative real part of the permittivity into opal pores results in a decrease in the effective
refractive index and a short-wavelength shift in the spectral position of the stop band in artificial opal. 相似文献
35.
Yu. P. Voinov V. S. Gorelik A. R. Zaritskii M. N. Maslova L. L. Chaikov 《Bulletin of the Lebedev Physics Institute》2013,40(8):230-235
In this paper, we present the results of the study of supernatant liquid of washed erythrocytes by the photoluminescence upon ultraviolet excitation. The spectra of intrinsic photoluminescence of an aqueous solution of “Sodium adenosine triphosphate-Vial” (Na2ATP) were compared with the spectra of supernatant liquid of erythrocytes with added Na2ATP, glucose, and without additional substances. The results of the comparison suggest that ATP emerging from washed erythrocytes into environment can be recorded in supernatant liquid. 相似文献
36.
The behavior of the relaxation time of order-parameter fluctuations in the isotropic phase of PAA nematic liquid crystal was
investigated on the basis of the spectra of depolarized (inelastic) light scattering in a wide temperature range including
the immediate vicinity to the temperature of the nematic phase transition. The experimental data were analyzed within the
Landau—de Gennes theory. The temperature limits of applicability of the Landau—de Gennes theory to the isotropic-phase dynamic
properties are obtained. The minimum correlation length is determined, at which the effect of local ordering on the dynamics
of slow orientational motion of isotropic-phase molecules is dominant. 相似文献
37.
The IR spectrum of methyltrifluorosilane is measured in the range 220–3500 cm?1. Both the equilibrium configuration of the molecule and its vibrational frequencies are calculated quantum chemically. Using the rotational and Coriolis constants obtained in these calculations, the contours of the rotational bands in the IR spectrum are numerically modeled. A comparison between the calculated and the experimental spectra made it possible to refine the frequencies of the fundamental vibrations of the molecule and determine the isotope shifts of the fundamental Si-F vibration with respect to the stable isotopes of silicon. 相似文献
38.
T. M. Valova A. M. Gorelik V. A. Barachevsky 《Russian Journal of Applied Chemistry》2017,90(4):501-506
Procedure was developed for surface dyeing of polycarbonate glass with photochromic thermally relaxing compounds from the classes of spiropyrans, spirooxazines, and chromenes via diffusion of photochromic molecules from solutions in cyclohexanone. It was shown that the highest diffusion efficiency of photochromic compounds without loss of the optical surface quality of polycarbonate glass is reached at a temperature of 80°C. Samples of photochromic polycarbonate glasses were obtained and their photochromic properties were studied. 相似文献
39.
L. Y. Gorelik Anna Grincwajg M. Jonson V. Z. Kleiner R. I. Shekhter 《Physica B: Condensed Matter》1995,210(3-4):452-460
We calculate the photoconductance of two-dimensional ballistic microstructures subject to a high-frequency electromagnetic field. First, we study a simple quantum point contact. Absorption of photons is due to electronic transitions between different modes. A transition between a propagating and a nonpropagating mode results effectively in a backscattering process, and gives a negative or positive contribution to the current, depending on the gate voltage; the total quantized conductance acquires an additional, quite pronounced step-structure. Then, we demonstrate a new effect where the electron-photon interaction in a structure of slightly more complex geometry plays the same role as impurity scattering does in a “dirty” system. All relevant photons of the external electromagnetic field are coherent and spatial interference effects in electron-photon scattering become possible in spite of the inelastic nature of the collisions. These interference effects can be controlled by the gate voltage or the frequency of the electromagnetic field. As an illustration we calculate the photoconductance of a double point-contact geometry. 相似文献
40.
The spectra of two-photon-excited fluorescence in the near ultraviolet are studied in diamond powders prepared by detonation synthesis, with particle sizes of 20–40 Å. The spectra of ultradisperse diamond powders are compared with that of a diamond single crystal. It is shown that the proposed method can be used to detect ultradisperse diamonds in quantities as low as 10?12 g. 相似文献