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The propagation of acoustic waves in a porous medium partially filled with a gas hydrate was investigated with regard for the viscoelastic properties of the skeleton of this medium on the assumption that the gas hydrate is distributed homogeneously in the thin layer at the inner surface of pores of the medium. A system of equations defining the propagation of acoustic waves in a porous medium containing a gas hydrate is proposed. A dispersion relation has been derived for investigating the influence of different parameters of a porous medium on the propagation of acoustic waves in it.

The process of reflection of acoustic waves through a porous medium in the case of their oblique incidence have been considered. It has been shown that as the angle of incidence increases, there is a decrease in the transmission coefficient.

Wave processes in wet porous media saturated with gas-vapor mixture have been studied with allowance for interphase interaction forces and heat and mass exchange between the skeleton of the porous medium and the gas-vapor mixture. Dispersion relations have been obtained for a porous medium saturated with gas-vapor mixture, vapor, or gas.

This paper studies the evolution of a wave pulse during propagation through a porous obstacle located in a gas and saturated with it. The cases of open and closed boundaries of the porous obstacle are considered. The effect of the parameters of the porous medium such as the initial value of the gas volume fraction and pore size and interfacial heat transfer on the evolution of the wave pulse was analyzed.

The process of propagation of acoustic waves in humid, gas-saturated porous media is investigated in a two-velocity approximation. A dispersion relation is derived, which includes interphase interaction forces and heat transfer between the skeleton of porous medium, liquid, and gas. The effect of heat transfer between the phases on the propagation of the “fast” and “slow” waves is included by means of heat equation

The effect of gas–skeleton heat‐transfer processes on propagation of fast and slow waves in a porous medium is examined. Frequency intervals are identified, in which attenuation of waves in a gas‐saturated porous medium is mainly controlled by the heat‐transfer processes.

Consideration has been given to the process of decomposition of a gas hydrate saturating a porous volume under the action of the energy of radiation through its boundary. It has been adopted that the zone lying in the vicinity of the boundary and saturated with the products of decomposition of the gas hydrate is transparent to radiation; the far zone saturated with gas hydrate and gas, conversely, is completely opaque; therefore, the radiation energy is totally absorbed at the boundary of phase transitions between the zones mentioned. The self‐similar solutions of plane one‐dimensional and radial‐symmetric problems have been constructed. The influence of the radiation intensity and of the parameters of the porous medium–solid gas hydrate–gas system in the initial state on the maximum pressures produced in the zone of decomposition of the gas hydrate has been analyzed based on the analytical solutions obtained.

The feasibility of a microwave waveguide made of plasma channels under laser pulse filamentation is discussed. The necessary channel bunch configuration is achieved by initial intensity modulation of a femtosecond pulse. Estimations are given for wavelength of the microwave radiation and for parameters of the plasma channels configuration.

To study a possible role of coronary circulation condition in remodeling heart in ischemic heart disease (IHD) patients with hypertension or without it.The examination (veloergometry, echo-CG and Doppler echocardiography, selective coronaroangiography and left ventriculography) covered 45 hypertensive men with angina of effort functional class III and 69 normotensive patients. Mean age of the patients was 51.8 +/- 1.2 years, duration of the angina 3 to 10 years.Correlation analysis of the data on hypertensive examinees discovered a direct correlation between proportional overall lesion of the coronary arteries, myocardial mass index and left ventricular (LV) index of systolic sphericity, between the sphericity index and myocardial mass index. An inverse correlation--with LV ejection fraction.In anginal patients, coronary circulation is an independent factor influencing LV remodeling. With progression of coronary failure remodeling intensifies. In patients with angina arterial hypertension contributes to the same degree to an increase in the personage of overall affection of the coronary bed, LV systolic sphericity index and index of its myocardial mass, forms an integral, global risk of heart remodelling and, later, heart failure.