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The experimental approach is outlined for study of heat fluxes on the surface of a blunt body of revolution (with kinked generatrix) in a hypersonic gas flow. The main attention is paid to the effect of coolant injection flow rate on resulting heat flux at different Reynolds numbers and attack angles. The significant role of distributed gas blowing on a body surface for the heat flux distribution has been demonstrated.

We present the results of designing the contours of supersonic parts of the solid-propellant rocket motor (solid motor) nozzles with high expansion ratios with the aid of direct variational methods. A continual model is used for the motion of a two-phase polydispersed continuum with regard for processes of interaction both between the carrying gas and the particles suspended in it and between the particles of various fractions. The method of local variations is employed as a numerical method of searching for the extremum of a multivariate function. The computational results evidence a fair efficiency of the proposed approach for the optimization of such nozzles.

The development of a non-self-similar liquid-liquid jet of a non-Newtonian reactive liquid is considered within the framework of the boundary layer theory. The analytic expressions are obtained on the basis of the local similarity method for variation of integral parameters of jet flow along its axis, which agree fairly well with the numerical solution of a non-self-similar problem.

A joint testing of the specialized (VP2/3) and universal (FLUENT) packages of applied programs of the hydrodynamic and thermophysical profile is carried out on the basis of the solution of a well-known problem of recirculation flow of a viscous incompressible fluid in a lid-driven square cavity. The Reynolds-averaged Navier ? Stokes equations are solved with the aid of implicit factored computational procedures. The adequacy of chosen one-, two- four-parametric semiempirical differential models of turbulence is analysed in detail.

The models of heat and mass transfer in foam scrubbers and centrifugal-bubbling apparatuses developed previously by the authors are refined. This upgrade takes into account the Stefan flow at high humidity of the treated air.

Preparative methods of the synthesis of organylsulphanyl(sulphonyl)acetic acids and their 2-hydroxyethylammonium salts developed by the authors are presented in this review. The latter salts represent a new class of pharmacologically active substances possessing antiaggregant, membrane-stabilizing, antioxidant, cytostatic, cardiotropic and hypocholesterolemic activity. Compounds with combined immunotropic and antitumour activity promising for the development of up-to-date remedies for treating immunodeficient, autoimmune, oncological and other diseases were found.

Electron Spin Echo Envelope Modulation (ESEEM) spectroscopy in conjunction with biochemical techniques of site-directed spin labeling and deuterium substitution in molecules or parts of molecules can be used to gain insights into supramolecular structure of biological membranes. The review covers the applications of this approach to study water penetration into the hydrophobic part of model phospholipid membranes and into the ion channels of biological membranes, to determine the localization and orientation of peptide antibiotics in membranes, and to investigate the conformations of enzymes and membrane proteins.

EPR and Mössbauer spectroscopy is used to study a new liquid crystal complex of iron(III) with a Schiff base: 4,4'-dodecyloxybenzoyloxybenzoyl-4-oxysalicylidene-2-aminopyridine with a PF^-₆ counterion. It is shown that Fe(III) ions exist only in the high-spin (HS, S = 5/2) state. It is found that under the influence of temperature the system demonstrates the stepwise behavior of the product of the integrated intensity of EPR lines (I) and temperature (proportional to χТ, where χ is the magnetic susceptibility) with an inflection point at ~80 K. Above 80 K a new EPR spectrum is detected due to the excited S = 2 state and the formation of dimeric molecules (through oxygen bridges) with a strong intramolecular antiferromagnetic exchange interaction J₁ = 162.1 cm^–1. Below 80 K iron(III) complexes are organized in 1D chains where the exchange value J₂ = 2.1 cm^–1. At 80 K there is a structural phase transition in the system: the transition from a 1D chain organization of HS Fe(III) centers to dimeric molecules. Based on quantum chemical calculations a model of the binuclear iron(III) complex is proposed.

Results of the ⁷Li, ¹⁹F, and ²³Na NMR studies of ionic mobility in bismuth fluoride glasses in the systems BiF₃–LiF and BiF₃–MF–ZrF₄ (M = Li, Na, K, Cs) are summarized. Analysis of the ⁷Li, ¹⁹F, and ²³Na NMR spectra made it possible to reveal changes in the nature of ion motions in the fluoride, lithium and sodium sublattices of glasses upon temperature variation and to determine their types. The temperature ranges were found where main types of ion motions in the tested glasses are represented by diffusion of lithium ions, reorientations of fluorine-containing groups constituting the glass network, and diffusion of fluorine ions. The role of alkali cations in the formation of ionic mobility in bismuth fluorozirconate glasses is considered.

The X-band PELDOR spectroscopy was used to investigate the magnetic dipole-dipole interactions in glassy solutions of nitroxide mono-labeled tylopeptin B and heptaibin peptaibiotics at 77 K. Specifically, a study was performed of the tylopeptin B peptides labeled at either position 3, 8 or 13, denoted as Т3, Т8 and Т13, respectively. The heptaibin analogs labeled at either position 2 or 14, denoted as H2 and H14, respectively, were also investigated. It was shown that in frozen glassy peptide solutions in methanol, the spin labels are randomly distributed over the solvent volume. This result points to the absence of specific dipolar interactions between the peptides under these conditions. However, peptide aggregation was detected in weakly polar methanol/toluene environments. To study the properties of the resulting aggregates, we examined the depth of modulation for the PELDOR traces as a function of the concentration of the peptides in solution and the distances between the spin labels in the aggregates. Based on the concentration dependencies, the number of peptide molecules in the aggregates was estimated. We find that this value ranges from 2 to 3, depending on the position of the spin label in the peptide sequence. The combined analysis of the distance spectra and the number of peptide molecules in the aggregates allows us to suggest that dimer formation is the prevailing mode of self-association. In the case of spin-labeled tylopeptin B, the molecules in the dimer are head-to-head oriented. In addition, the distance spectra of the aggregates show that the C-termini of the molecules in the tylopeptin B dimer are more mobile than the N-termini. This phenomenon leads to an increase in the spread of the distances between the nitroxides as the label position is approaching the peptide C-terminus. For heptaibin, we show that two forms of dimerization (head-to-head and head-to-tail) occur. Finally, in addition to dimers, aggregates containing 3 or 4 peptide molecules, which give broad lines in the distance spectra, are seen in solution.