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The application of degassed oil instead of recombined oil model for a slim tube technique was investigated. It is found that the use of degassed oil is not recommended for modeling and studying of gas and oil miscibility under typical conditions of Western Siberia deposits. The previously estimated miscibility of light oil and associated gas was confirmed in case of application of recombined oil model or degassed oil at displacement from a slim tube. This occurs because of a gradual transition from the mode of immiscible displacement to the mode of limited-mixing displacement of oil and further to the mode of complete mixing as a result of the mass exchange of light oil and associated gas.

The methods of extracting viscous oil from oil leg reservoir (oil rims) of the Cenomanian horizon are experimentally investigated (PK layers). It was found that steam contributes to the swelling and dispersion of clay components of the rock, i.e. thermal methods cannot be recommended for use. The effect of oil on the rock properties of PK layers was investigated. It was shown that permeability, wettability and degree of oil displacement by saline water depend on oil saturation, and the rock transition from hydrophilicity to hydrophobicity occurs at oil saturation above 75%. Alkaline flooding and the use of non-ionic surfactants are not effective for enhancing the recovery of PK layers. For oil displacement, it is recommended to apply a water-gas mixture or sequentially inject solvent and water (or water-gas mixture).

Under the conditions of the low-permeable Tyumen Formation, associated petroleum gas (APG) and intrastratal air transformation product are similar in oil-displacing properties. A new approach to the development of oil reserves of the Tyumen and Bazhenov Formations is proposed. It lies in the fact that, when solid organic matter of the Bazhenov Formation dispersed in the rock mass is oxidized, air; rather than oil, should be transformed into an inert gaseous agent. At the same time, artificial fractures will be formed if the rock of the Bazhenov Formation is heated unevenly.

Recently, the transformation from random to chaotic behavior in the statistics of Fano&ndash, Feshbach resonances was observed in thulium atoms with rising ensemble temperature. We performed random matrix theory simulations of such spectra and analyzed the resulting statistics in an attempt to understand the mechanism of the transformation. Our simulations show that, when evaluated in terms of the Brody parameter, resonance statistics do not change or change insignificantly when higher temperature resonances are appended to the statistics. In the experiments evaluated, temperature was changed simultaneously with optical dipole trap depth. Thus, simulations included the Stark shift based on the known polarizability of the free atoms and assuming their polarizability remains the same in the bound state. Somewhat surprisingly, we found that, while including the Stark shift does lead to minor statistical changes, it does not change the resonance statistics and, therefore, is not responsible for the experimentally observed statistic transformation. This observation suggests that either our assumption regarding the polarizability of Feshbach molecules is poor or that an additional mechanism changes the statistics and leads to more chaotic statistical behavior.

Mixtures of magnesium chloride and MeOH were studied as mixed thermodynamic inhibitors of hydrate formation. The equilibrium P,T-conditions for methane hydrate decomposition in the presence of binary solutions H2O—MeOH and H2O—MgCl2 and ternary solutions H2O—MeOH—MgCl2 were determined using an isochoric method in a stirred autoclave. Measurements were made at pressures of 3.5-9.5 MPa; MeOH concentrations, 0-25 mass%. The salt content in the aqueous solutions was constant at 5 mass%. The results showed that mixed samples containing MeOH and MgCl2 gave the largest thermodynamic shifts of hydrate formation as compared to samples with MeOH at the same inhibitor mass fraction. The larger thermodynamic shift was related to synergism between the affects of MgCl2 and MeOH in the aqueous solution.

A new method for preventing gas breakthroughs to producing well bottom during oil recovery from oil-gas condensate deposits, which enhances the efficiency of gas recovery technologies, is proposed. The method consists in use of hydrophobic gas shutting compositions based on furnace (residual fuel) oil. Filtration studies (physical modeling) of the gas shutting process were conducted for the proposed compositions. The gas breakthrough was simulated using permeable bulk porous media or permeable cores of productive bed of the reservoir.

It is shown that associated petroleum gas (APG) and the product of intrastratal transformation of air (by high-pressure air injection technology) are suitable for oil displacement from low-permeability, high-temperature light oil reservoirs. It was found that APG and air are effective gaseous agents miscible with oil, which are similar in oil-displacing properties. The minimum miscibility pressure (MMP) determination data are presented for an Upper Jurassic oil-APG system. The miscibility in the oil-APG system was achieved by the multicontact mechanism of interaction between oil and enriched gas. A new method is proposed for graphical determination of MMP as a function of gas breakthrough due to pressure, and a method for enhancing gas impact efficiency and for achieving miscibility at a pressure below the MMP, which consists in injection of a liquefied gas prefringe or a wide fraction of hydrocarbons, is validated.

Use of a combination of multistage hydrofracking and high-pressure air injection is proposed for developing low-permeability oil deposits of the Tyumen Suite (Upper Jurassic). An effective inert gaseous agent is formed during intrastratal transformation of the air due to oxidation of the oil. The oil autooxidation mechanism is studied. A weak dependence of the oxidation rate on the oil properties is observed.

Aerodynamic problems arising during design and development of braking systems for re-entry vehicles are analyzed. Aerodynamic phenomena and laws valid in a supersonic flow around a pair of bodies having different shapes are studied. Results of this research can be used in solving application problems (arrangement and optimization of experiments; design and development of various braking systems for re-entry vehicles moving with supersonic speeds in the atmosphere).

Series of functionalized pyridinium alkyl[poly(oxyethylene)] phosphites, isoquinolinium alkyl[poly(oxyethylene)] phosphites, pyridinium aryl[poly(oxyethylene)] phosphites, and isoquinolinium aryl[poly(oxyethylene)] phosphites were obtained and their properties were studied systematically. Some of them were found to be effective corrosion inhibitors in aqueous CO2-and H2S-containing media. Isoquinolinium dodecyl-and dodecylphenyl[dodeca(oxyethylene)] phosphites proved to be the best inhibitors. The isoquinolinium aryl[poly(oxyethylene)] phosphites obtained were used to create a new corrosion inhibitor.

The aerodynamic characteristics of cone-sphere models are studied at Mach numbers M = 6, 8.4, and 12 to 13 over a wide Reynolds number range. Models of a braking device (sphere) were connected with a load (frustum of a cone) by means of shrouds. The dependences of the aerodynamic coefficients C x and C y on the angle of attack α were obtained for different relative dimensions of the load and the braking device, shroud lengths, and Mach and Reynolds numbers. The effect of the above-mentioned parameters on the aerodynamic characteristics of the models is analyzed. The C x (ReD) dependences of load-parachutemodels in a symmetric flow are determined over the wide Mach and Reynolds number ranges 6 ≤ M ≤ 13 and 3 · 103 ≤ ReD ≤ 3 · 106.

The flowfield and the aerodynamic drag of a model consisting of a pair of bodies (leading body a cylinder and trailing body a hollow cylinder) connected by a cylindrical bar along the axis of symmetry is experimentally investigated at Mach numbers ranging from 0.6 to 1.7. In the course of the experiments, the trailing body cavity depth and the connecting bar length were varied.

Protective effects of aryloxycarbonylmethylisoquinolinium chlorides on the iron surface were studied. The best results were obtained with decylphenoxycarbonylmethylisoquinolinium chloride (DPCMIQC) containing the alkyl C10 in the aryl fragment. This salt was used as an active component in an SNPKh-type corrosion inhibitor. Experimental data for this inhibitor were compared with the results obtained in bench and commercial field tests in West Siberia and the Ural-Volga region.

The distinctive features of the flow in the region of interaction between an oscillating shock and a flat-plate boundary layer are studied for the laminar, transitional, and turbulent flow regimes. The flow patterns and the pressure and heat transfer distributions in the interaction region are analyzed at different intensities, frequencies, and amplitudes of the oscillating shock. The results of the interaction of oscillating and steady shocks with the flat-plate boundary layer are compared.

Results of experimental investigations of trans‐ or supersonic flow around two bodies (cone–disk or sphere–disk) connected by a cylindrical rod along the axis of symmetry are presented. The special features of the flow are analyzed. It is found that the dependence of the drag coefficient Cx of a pair of bodies on the Mach number within the range 0.6 ≤ M ≤ 1.7 is nonmonotonic. The reasons for the hysteresis in the dependences Cx(M) for two bodies at the stages of flow acceleration and deceleration and discrete variation of the Mach number are clarified. The influence of cone angles and sizes of both bodies on the drag coefficient is estimated.

Transonic and supersonic flows past a pair of bodies have been experimentally investigated. The leading bodies were spheres, cylinders, and cones, while the trailing bodies were flat-ended circular cylinders. The leading and trailing bodies were joined by cylindrical rods of various lengths, aligned with the axis of symmetry. For these models, the pattern of flow between the bodies and the Mach number dependence of the drag coefficientC x were determined in the acceleration and deceleration flow regimes in a wind tunnel. The experimental results are used to analyze the properties of the flow between the bodies and the variation of the aerodynamic coefficients of the models. The reasons for the hysteresis in the behavior of the coefficients in the acceleration and deceleration stages are discussed. The influence of the shape and dimensions of the leading body on the modelC x is evaluated.

Immunisation with outer membranes of Francisella tularensis induced an efficient protection in guinea pigs against challenge with the virulent strains 503 or 144/713 (type B biovar holarctica), both clinical isolates, and prevented the development of typical signs of infection in hamadryads (baboons), challenged with the virulent strain Schu (type A, biovar tularensis) of F. tularensis. Immunisation with a lipopolysaccharide protein complex isolated from the outer membranes afforded protection in CBA mice against challenge with strain 503. Another LPS-protein complex obtained by the simple mixture of LPS preparations from strain 503 and a 17-kDa membrane protein from the avirulent R-variant of the vaccine strain 15 also demonstrated protective properties against experimental tularemia in mice.

In the post-Newtonian approximation of the metric theory of gravitation we calculate the frequencies of Shirokov oscillations for equatorial circular geodesics in an asymptotically flat static space-time which satisfies the conditions of axial symmetry and symmetry with respect to the plane of the equator.

A technique for the determination of the strain-rate sensitivity of hardness during dynamic nanoindentation is proposed. The strain-rate sensitivities of the dynamic hardnesses of a wide class of materials (fcc metals, carbon steels, bulk amorphous metallic alloys, ionic and covalent crystals, polymers, and ceramics) are determined. The variation of these strain-rate sensitivities with the relative-strain rate (in the $$\dot \varepsilon $$ range from 3 × 10−3 to 5 × 103 s−1) and the indentation depth (in the range from 30 nm to 2μm) is studied.

The problem of integration is discussed for a complete system of Newman-Penrose equations for electrovacuum spaces of the general theory of relativity with nonzero cosmological constant. In terms of the method of spin coefficients, we formulate conditions on the electromagnetic and gravitational field variables, which distinguish a special class of Riemann spaces corresponding to strong gravitational waves in semiclosed Universes of Bertotti-Robinson type.

The problem of finding a particular family of algebraically special exact solutions to the Einstein-Maxwell equations with a non-vanishing cosmological constant is considered in terms of the Newman-Penrose formalism. The new family, corresponding to the case of an aligned ( Phi 0=0), non-radiative ( Phi 2=0), and constant ( Phi 1=constant) electromagnetic field, has been found explicitly. Each metric from this family contains three arbitrary real functions a(u), b(u), c(u) of the null retarded coordinate u and one arbitrary complex function G(u, zeta ) of the same coordinate u and the complex variable zeta . The main geometrical features of these solutions are discussed. It is noted that the Riemannian manifolds determined by these solutions admit the spacelike wave surfaces of the constant Gaussian curvature, whose type and radius depend on the values of the cosmological constant Lambda and the invariant Phi 1 Phi 1 of the electromagnetic field.

A series of solutions of Einstein's equations with Λterm is found; it describes the gravitational field of quasistationary concentrated systems containing electric and magnetic charges. The metrics are of Petrov type D and have rotation and expansion. The solutions are interpreted physically. In this, the second part of the paper the complete system of Newman — Penrose equations is integrated under the formulated assumptions.

The kinetics of formation of acetic acid, methanol, methyl acetate and hydroperoxide in the autoxidation (463–503 K) and initiated oxidation (413 K) of pentaerythritol tetraacetate has been studied. A scheme for product formation is proposed.

It has been noted that the family of plane electromagnetic waves and the “electromagnetic universe” of Bertotti-Robinson exhaust the entire class of conformally flat Einstein-Maxwell spaces. In the formalism of Newman-Penrose a family of exact solutions of the Einstein-Maxwell equations of the type of Bertotti-Robinson is obtained with a cosmological term belonging to the degenerate type D in the algebraic classification of Petrov and describing the space-time generated by a covariantly constant, nonisotropic electromagnetic field.

We consider the process of integration of a complete system of Newman-Penrose equations for electrovacuum spaces of the general theory of relativity with nonzero cosmological constant. The restrictions used for the field variables correspond to strong gravitational waves in semiclosed Universes of Bertotti-Robinson type.

Integration of transversal Newman-Penrose equations for electrovacuum spaces of General Relativity, corresponding to strong gravitational waves in semiclosed universes of the Bertotti-Robison type, is considered. The space-time metric belonging to the degenerated type II according to Petrov's classification, is explicitly given, and some of its properties are discussed.