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The paper is resumptive. The results of different authors in the field of water-steam plasma technological application are presented. Particular attention is given to the water-steam plasma obtained with the aid of an electric arc. The experience suggests that the future lies with this very technique of plasma generation since electric-arc generators of plasma have high efficiency and practically no limitations both in capacity and in the flow rate of a plasma-forming gas, which is especially important for a large-capacity industry.

The results of experimental investigations of electron concentration distribution in a cathode cavity and charge column, of plasma potential on a column axis, of electron temperature in the column are presented, as well as the topograms of equipotential surfaces and the lines of equal temperatures of electrons. The analysis of the obtained characteristics allowed to determine the reasons of localization of the most heated region of the cathode inside the cavity and the dependencies of temperature maximum position on electric current and plasma-forming gas flow rate, and the mechanism of self-maintaining of the region of maximum potential decline inside the cathode hollow where the main power is supplied into the discharge plasma; this analysis also permits to clarify the role of the plasma-forming gas and its flow rate in generating the processes progressing in a high-current arc discharge with the hollow cathode, and the reasons of high spatial stability of a plasma column in the inter-electrode space and plasma column orientation on the cathode axis.

Specific power inputs and other characteristics of plasma thermochemical preparation (TCP) of coal for incineration were calculated using the "Plasma

Basing on the equilibrium magnetogasdynamic model of plasma the computation of the gas (argon) flow and heating in the initial interval of a cylindrical channel provided with a diaphragm depending on the variation of the current strength, geometric parameters of the diaphragm, gas flow rate and torque has been carried out. The peculiarities of the behavior of the arc flow characteristics in the channels have been studied, which are related to a sudden variation of the cross section with and without regard for gas swirl. It is shown that for the localization of the plasma arc flow in the region near the axis it is necessary to mount a diaphragm also in the outlet cross section of the channel along with the gas swirl. The computed results agree qualitatively with experimental data.

The generation of crossflow instability waves in a swept-wing boundary layer by wing-surface vibrations is experimentally studied. For various disturbance frequencies, the excitation of wave trains of vibration-induced disturbances and their further development in the boundary layer are quantitatively examined. Following a Fourier decomposition of the wave trains into normal three-dimensional modes, the spectral amplitudes of various instability modes were compared with the amplitudes of respective spectral surface-vibration components. As a result of the study, complex-valued receptivity coefficients were obtained for various disturbance frequencies as functions of spanwise wavenumber, which turned out to be independent of the particular shape of surface vibrations.

To study flow characteristics before and behind the obstacle, an attachment region position of a separated flow and flow structures near an underlying surface, a shear subsonic turbulent flow around two-dimensional obstacles of a square cross section was experimentally investigated. The aspect ratio of the obstacle height to the turbulent boundary layer thickness in a mounted point of the model h/  was varied from 3.2 up to 0.2. It is shown that at a larger part along a wingspan (transverse coordinate) the upper obstacle surface flow has a quasi-two-dimensional character, excluding the regions bearing against side ends. At the same time a flow structure near the underlying surface is three-dimensional practically in all cases. For certain, attachment of the shear layer separated from the obstacle has an unstable character. It was set a dependence of the attached region position of the separated flow on the obstacle immersion level in the turbulent boundary layer. The influence of a slip angle on a separated flow transformation and on a width of the quasi-two-dimensional flow region is shown.

By using the flows past planar and conical shocks near the axisymmetric cones at zero incidence the characteristics of the waveriders are investigated, whose lower surface is described by a power-law function. A parametric analysis of the effect of the cross section shape on the lift-to-drag ratio has been carried out for the on-design flow regimes, and also the data have been obtained on the integral heat fluxes for a given surface temperature T _w = const. The results of comparison are presented for different constraints for the geometric parameters of waverider configurations, which are optimal in the lift-to drag ratio sense for the considered types of the basic flow.

Deformed molecules exhibit anomaly in various aspects. Mechanical stressing, being anisotropic in nature, on the molecular crystals inevitably brings about quenched deformation of constituent molecules. When we deal with coordination compounds, deformation of the molecule results in disproportionation of ligands to change them into asymmetric, and hence develops distribution of ligand field strength. Consequences of introducing such asymmetry are very diverse. Gradual spin crossover and substitution of ligands by counter ions are only a few examples. Solid state ligand exchange is particularly of importance, since this opens up a new way for synthesizing various coordination compounds using neither solvents nor catalysts. Evidences of distribution of ligand field strength are shown for ferrous coordination compounds. Subsequently, application to the synthesis of some ferrous pyridyl compounds is demonstrated.

Defect formation and activation of agglomeration during mechano-chemical treatment of tungsten powder and its mixtures with copper and nickel are considered. Mechano-chemical activation in high-energy strain mills is accompanied by the decrease of coherent lengths (to 10 nm), accumulation of microdeformations (up to 0.2-0.3 %) and increase of tungsten lattice parameter, as well as by profound mixing of the components. Besides, the system gets contaminated with iron impurities. Chemical transformations during the annealing of samples with different doses of mechanical treatment are analyzed. The application of mechanochemical activation allowed us to obtain well agglomerated W/Ni/Cu alloys at annealing in the absence of hydrogen (density: up to 16 g/cm³; Wickers' hardness: up to 550 kg/mm²). Optimal dose of mechano-chemical activation is determined (10-115 kJ/g); optimal regime of powder pressing is revealed. The effect of iron impurities on the hardness of agglomerated tablets is investigated.

An investigation of mechanically stimulated self-propagating reactions (MSR) has been carried out for different conditions of mechanical activation in the system Zn-Sn-S using a SPEX 8000 mill. Both the earlier obtained and new results are generalized, with focus on the determination of induction period preceding the ignition of exothermal reaction. The discovered features and some hypotheses concerning the mechanism of MSR are discussed.