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1.
Results of acoustic measurements in skeletal muscle are generalized. It is shown that assessment of the pathologies and functional condition of the muscular system is possible with the use of shear waves. The velocity of these waves in muscles is much smaller than the velocity of sound; therefore, a higher symmetry type is formed for them. In the presence of a preferential direction (along muscle fibers), it is characterized by only two rather than five (as in usual media with the same anisotropy) moduli of elasticity. A covariant form of the corresponding wave equation is presented. It is shown that dissipation properties of skeletal muscles can be controlled by contracting them isometrically. Pulsed loads (shocks) and vibrations are damped differently, depending on their frequency spectrum. Characteristic frequencies on the order of tens and hundreds of hertz are attenuated due to actin-myosin bridges association/dissociation dynamics in the contracted muscle. At higher (kilohertz) frequencies, when the muscle is tensed, viscosity of the tissue increases by a factor of several tens because of the increase in friction experienced by fibrillar structures as they move relative to the surrounding liquid; the tension of the fibers changes the hydrodynamic conditions of the flow around them. Finally, at higher frequencies, the attenuation is associated with the rheological properties of biological molecules, in particular, with their conformational dynamics in the wave field. Models that describe the controlled shock dissipation mechanisms are proposed. Corresponding solutions are found, including those that allow for nonlinear effects. 相似文献
2.
3.
Demin D. L. Dzhelepov V. P. Filchenkov V. V. Grafov N. N. Grebinnik V. G. Migachev D. V. Konin A. D. Rudenko A. I. Sidorov V. T. Zhestkov Yu. G. Zinov V. G. Davies J. D. Bom V. R. van Eijk C. W. E. 《Hyperfine Interactions》1996,101(1):13-19
The ddµ molecule formation rate is experimentally measured for the two hyperfine states of the dµ-atom in the temperature range of 5–30 K. Results are consistent with a preliminary measurement by the TRIUMF group and contradict theoretical predictions. The work has been performed on the JINR phasotron (Dubna). 相似文献
4.
V. G. Berezkin E. Yu. Sorokina A. I. Sokolov B. A. Rudenko 《Journal of Analytical Chemistry》2003,58(1):61-67
The effects of the presence of water vapor in the carrier gas and the temperature on the retention of achiral and chiral compounds, enantioselectivity, and performance of an open-tubular column with a cyclodextrin-containing phase were studied. The use of a carrier gas containing water vapor in the determination of optically active isomers, such as camphor, slightly increases the retention factor. A substantial improvement of performance characteristics of the column was found: for hydroxy compounds, the column performance increased by two to three times and the peak symmetry improved by more than twice. 相似文献
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6.
V. V. Berentsveig Zaki A. Hasan P. B. Fabrichnyi T. M. Ivanova A. P. Rudenko 《Reaction Kinetics and Catalysis Letters》1980,15(2):239-243
The state of mixed iron-tin oxide catalysts with a variable ratio of their metallic components has been studied by Mössbauer and ESCA spectroscopy. The results are compared with the activity of these catalysts in cyclohexane oxidation.
- . .相似文献
7.
A mechanism explaining streamer propagation to the anode and to the cathode without photoionization of the gas is proposed. It is shown that the velocity of the anode streamer is determined by the electron mobility in the field of the end of the streamer. The accelerated electrons appearing at the anode end of the streamer excite longitudinal plasma oscillations in the streamer, whereupon streamer propagation to the cathode is explained. An explanation is given of the phenomenon of streamer self-propagation after the disappearance of the external field because of the stored energy of the plasma oscillations. The conditions for the transition of an avalanche into a streamer is defined as the condition for the appearance of accelerated electrons at the anode end of the avalanche.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 7, pp. 34–39, July, 1977. 相似文献
8.
B. A. Rudenko N. P. Shoromov M. A. Kumakhov O. O. Naida 《Journal of Analytical Chemistry》2005,60(10):956-960
The possibilities for multicapillary tubes with channels 3–10 μm in diameter and a total number of channels of about 2 × 105−106 to be used as chromatographic columns are studied. It is shown that substances with a sufficiently high boiling point can
be separated at temperatures of 20–30°C in 2–3 min with an efficiency of about 1500 theoretical plates per meter (300 theoretical
plates for a 20-cm column).
__________
Translated from Zhurnal Analiticheskoi Khimii, Vol. 60, No. 10, 2005, pp. 1075–1079.
Original Russian Text Copyright ? 2005 by Rudenko, Shoromov, Kumakhov, Naida. 相似文献
9.
Yu. N. Rabotnov S. A. Kolesnikov V. S. Matitsyn I. M. Makhmutov V. A. Rudenko E. I. Stepanychev 《Mechanics of Composite Materials》1976,12(2):202-207
The effect of reinforcement schemes that differ in the magnitude of the disorientation angle of neighboring filler layers on the mechanical properties of a "carbon-carbon" composite under extension, compression, or bending is shown.Translated from Mekhanika Polimerov, No. 2, pp. 235–240, March–April, 1976. 相似文献
10.
Doklady Physics - In this paper, we describe a diagnostic method based on “acoustic weighing” of sheet materials. The defect mass or mass deficit determines the frequency shift of the... 相似文献