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The possibility of forming of the geological depth image from marine seismic data observed with the method of reflected waves by multiple overlaps and the refracted method by deep seismic sounding was investigated. The difference in the algorithms for the creating of depth image using the finite-difference migration on the field of reflected and refracted waves is shown. Also there is presented the possibility of comparing and generalizing their results. Researches were carried out using the example of seismic data, observed with the method of reflected waves by multiple overlaps and the refracted method by deep seismic sounding in the area of the Azov Sea.

Features and basic principles of plotting the graph of marine seismic observations processing with application of original method of finite-difference total wave migration of the sum of central middle point, which is more stabile in case of investigation of complicated geological sections have been considered. The effectiveness of the method is demonstrated on materials of seismic marine observations performed on the continental slope of northwestern shelf of the Black Sea.

Results are presented of measurements of the friction drag, acoustic spectra of pipeline wall and pump pedestal vibrations as well as of the hydrodynamic noise during the motion of a fluid with surfactant admixtures of different nature in a closed hydraulic loop.

The estimation of the malignancy-associated changes in oral mucosa of patients with benign and malignant processes in mammary and thyroid gland is carried out on the basis of textural and densitometric indices of the interphase nuclei of the epitheliocytes with the help of the methods of mathematical statistics.

Altogether 144 patients with various forms of retardation of growth aged 1 to 24 were investigated. Somatotropic function of the pituitary body was assessed by the results of a stimulation test with clopheline. A STH level was determined by a radioimmunoassay. Somatotropic function was undisturbed in an overwhelming majority of cases of genetically determined retardation of growth. Hormone therapy was not indicated in these cases as it could lead to unfavorable results: decreased indices of definitive growth resulting from the formation of antibodies to the growth hormone.

The purpose of this work was to comparatively study the corrosion activity of aqueous systems with reduced hydrodynamic resistance which can be used as heat transfer fluids and coolants in heating and cooling systems. Liquids of three types were investigated. The first includes solutions containing anion-active surfactants, sodium chloride, and water. The second consists of aqueous solutions containing surfactants and sodium nitrite as the electrolyte. The third form consists of an aqueous suspension of asbestos fibers with a surfactant for stabilization. Results confirm that the use of these systems can lead to a reduction of 20 to 30 percent in power required for pumping and a reduction of 10 to 12 percent for materials required for piping by making possible the use of decreased-diameter piping.

Results from a series of pipe-flow experiments using a range of water-soluble drag-reducing polymers are presented. Degradation has been investigated by means of multiple passes of the solutions through a pipe. A theory predicting drag reduction in pipe flow has been devised which agrees with the experimental results. Changes in polymer molecular weight due to degradation are taken into account. The analysis is then applied to a turbulent boundary layer with polymer injection.

A scheme to compute the friction and heat-transfer coefficients for a fluid flow with polymer admixtures to reduce friction, based on the mixing-path-length representation, is proposed. The influence of the molecular Prandtl number, the Reynolds number, and the magnitude of friction reduction by polymer molecules on the regularities of heat transfer is analyzed. Formulas are obtained to determine the heat-exchange coefficients. The results of computations by means of the scheme proposed are in satisfactory agreement with experimental results.

The motion of a plate in the presence of distributed addition of a polymer solution is studied on the basis of a system of partial differential equations. The calculations take into account the influence of the additives on the coefficients of molecular and turbulent viscosity and diffusion. The influence of the concentration and rate of injection of the polymer solution on the profiles of the tangential frictional stress, the averaged velocity, and the local and total frictional drag coefficients is analyzed. The results of calculations are compared with data on the drag of a plate when a polymer solution is injected near its leading edge.

The problem of the drag of a plate moving in a weak polymer solution is solved on the basis of a three-layer schematization of the velocity distribution in the turbulent boundary layer.

Experimental investigations show that the presence in a fluid of fibers and rigid asymmetric particles leads to a greater stability of flow in tubes and lowers the turbulent frictional resistance in a certain range of Reynolds numbers [1]. In the present paper, the anisotropic structure of a fluid with additives is described by Ericksen's rheological model [2]. The parameters of the model are particularized in accordance with the paper [3] of Pilipenko, Kalinichenko, and Lemak, and in the limiting case of weak Brownian motion allowance is made for the effect of the predominant orientation of the particles and the influence of additives on the longitudinal and shear viscosity. The stability of the Poiseuille flow is considered in the linear formulation. In an anisotropic viscous fluid, an equation of Orr-Sommerfeld type has a singular point. A rule for choosing the path of integration avoiding the singular point is obtained on the basis of a generalization of the method of Dikii [4] proposed in an investigation of the stability of the flow of an ideal fluid. The results of numerical calculations of the neutral stability curve for two-dimensional perturbations are given.

A formula for turbulent viscosity which allows a simple analytic expression to be obtained for the distribution of the averaged velocity of turbulent liquid flow at a rough surface is proposed.

One of the methods of reducing the frictional resistance of bodies moving in water is the discharge of a water-soluble polymer admixture into the turbulent boundary layer on the surface of the body. For dilute polymer solutions having constant concentration, existing semiempirical methods of calculation which use information on the effect of long molecules on the rearrangement of the flow in the boundary layer enable one to calculate the resistance of smooth and rough tubes [1] with sufficient accuracy and to analyze effects of the redistribution of local tangential stresses on the surface of plane plates [2]. Methods of calculating the drag of plates that have been developed up to the present time are also suitable for predicting the reduction of turbulent friction of elongated bodies by polymer admixtures. It is of interest to generalize these methods to the case of variable concentration. Below we consider the problem of calculating the turbulent boundary layer on a plane plate when a polymer solution is injected near its leading edge. For its solution we use the simplifying assumption that it is possible to replace the actual distribution of the concentration of polymer admixtures along a normal to the surface of the plate with an effective uniform distribution. This assumption enables us to estimate the discharge rate of the polymer that is required to obtain a given reduction in the frictional resistance.

The steady attention of investigators to the problem of turbulent drag reduction by polymer additives is connected both with the search of reasonable answers to the question, why insignificant quantities of a polymer (at concentrations about 10−6 – 10−4 g/sm3) are capable of changing the structure of wall turbulence efficiently, and also with practical supplements, the number of which is permanently increased.