Simulation of hydrodynamic perturbations in the boundary layer of the swept wing model by means of vibrations of a localized surface area and investigation of disturbances development under conditions of low turbulence of the incoming flow were carried out in the subsonic wind tunnel. The results of research are obtained using the method of anemometry. It is found that the pulsed action of a portion of the surface on the boundary layer leads to the generation of perturbations-a longitudinal localized structure and wave packets near its fronts. The effect of the secondary flow and the pressure gradient on the development of simulated perturbations is studied in detail.

The experimental results of investigation of the effect of a pair of weak shock waves on the boundary layer of a flat plate with a blunt leading edge are presented at Mach number 2. Generation of weak shock waves was carried out using two-dimensional stickers 2.5 mm wide and 120 μm in thickness and 230 μm in thickness. The perturbations generated in the free flow have the configuration of N-wave. Its amplitude is 5 and 11 % respectively. In the boundary layer the generation of stationary longitudinal vortices by fronts of the N wave was detected. They do not spread downstream. The interaction of weak Mach waves with the boundary layer leads to an increase of the low-frequency vibrations of the shear layer.

The experimental research of influence of focused impulsno-periodic radiation СО2 - the laser on initiation and development of process of distribution of burning in to and a supersonic stream homogeneous fuel-air of mixes (СН4 + air) is spent. Radiation СО2-laserа extended across a stream and was focused by a lens on an axis of a supersonic stream. The shadow scheme was applied to registration of structure of a current with a crack and the flat knife located along a stream. The image it was fixed by the high-speed chamber in due course expositions 1.5 µs and frequency of shots 1000 1/s. It is shown, that at cross-section input of laser radiation in a flux the periodic structure of a thermal trace, with a forming of head jump of a gland from a band energy deposition is formed. At small frequencies of a resulting of pulses of laser radiation interaction of a thermal cloud with a flux occurs in a pulse mode. Is developmental process of non-stationary ignition by the optical category of a metano-air mix is shown at the subsonic expiration in motionless atmosphere. Results of optical visualization testify about burning in a trace behind a field of the optical category.

This work is devoted to the estimation of the possibilities of investigating the boundary layer on the varioform-sectional wing with the help of an acoustic sensor and an absolute pressure sensor. The base model was a wing with a rigid wavy surface. In the boundary layer of this model, a large number of measurements were made using the technique of thermoanemometric measurements. The article compares velocity profiles and pulsation profiles obtained with a thermoanemometer and with the help of an acoustic sensor and a pressure sensor. It is shown that the presence or absence of a laminar-turbulent transition (LTP) and a local separation zone (LSZ) can be qualitatively determined with the aid of an acoustic sensor and a pressure sensor. However, quantitatively, the data obtained by different sensors may be different. The difference in the position of the maximum amplitude of pulsations obtained by the thermal anemometer and the microphone sensor differs by 5- 20 % over the chord. This depends on the presence or absence of a local separation zone in the measurement area. The longitudinal component of the average velocity in the boundary layer in the region of the separation zone obtained by the absolute pressure sensor can differ from that obtained by the method of thermal anemometry by 80 %.

The polymer-liquid crystal films formed by evaporation of solvent from the solution containing liquid crystal (derivatives of cyanobiphenyls) and polymer (polyvinyl acetate) in the presence of a magnetic field studied experimentally. It is shown that the use of weak magnetic fields of different directions during the formation of films orders the orientation of liquid crystals in one direction (the field is parallel to the plane of the film) or with a small angle of deviation of their axes from the surface of the film (the field is orthogonal to this plane). The change in the liquid crystal texture in the film results in the change of their light transmittance and dynamic characteristics in electric fields.

The coatings based on tetrahedral amorphous carbon were deposited through the diaphragm of 27 mm diameter on silicon substrates by a pulsed cathode-arc source at three different distances between the source and the substrate: 150, 215 and 265 mm. The structure and mechanical properties of the produced tetrahedral amorphous carbon films were studied using Raman spectroscopy and nanoindentation. The results showed that as the source-substrate distance increases, the structure of the films changes. The decrease in the concentration of ordered aromatic rings in Csp² cluster and the increase in the concentration of chain groups. The maximum values of nanohardness and Young's modulus are attained at the distance of 150 mm between the source and the substrate and are 21 GPa and 197 GPa, respectively. With the increase in the distance to 265 mm, these values decrease to 16 GPa and 177 GPa, respectively. Probably, at a close distance from the pulsed source, more closely packed structures are formed in the coatings, which affect the higher nanohardness. It is assumed that the formation of the coating structure depends on the source-substrate distance and is determined by the energy and spatial parameters of the pulsed plasma flow.

The short review of Raman scattering of light investigations and its analogs in different media, worked out from the time of this phenomenon opening up to our days, is presented. The main theoretical manners of different types of Raman scattering descriptions are presented, serving as the base for the new development of combinational optics. The main experimental setups for combinational processes observations are described. The applied and fundamental directions, connected with the combinational optics, are presented.

Multiple Stokes and anti-Stokes satellites in the Stimulated Parametric Raman Scattering spectra of liquids and crystals have been observed during excitation by ultrafast pulses of solid state laser YAG:Nd³⁺ with wave lengths of generation 1064 и 532 nm.

We report results of polarized Raman scattering and photoluminescence studies of nitrogen-doped diamond. Experimental data demonstrates observation of an anomalous increase in the intensity of the inelastic light scattering by optical phonons and photoluminescence at room temperature by both zero-phonon lines: for the neutral nitrogen NV⁰ center at 575.468 nm and for the other negatively-charged nitrogen NV^- center 637.874 nm as well as for their vibronic phonon side bands correspondingly distributed in a wide spectral range. The data enables observation of the strong in-coming resonance for nitrogen NV⁰ and out-going resonance for nitrogen NV^- centers.

Porous germanium films were produced by selective removal of the GeO2 matrix from the GeO2 heterolayer in deionized water or HF. On the basis of Raman and infrared spectroscopy data it was supposed that a stable skeletal framework from agglomerated Ge nanoparticles (amorphous or crystalline) was formed after the selective etching of GeO2 heterolayers. In the porous germanium films formed the sizes of the Ge nanocrystals were decreased due to oxidation in air and resonance Raman scattering appeared. Resonance Raman scattering was accompanied by photoluminescence (PL) (bands in the range of 2.1-2.5 eV and 1.5-1.7 eV) excited by a laser with quantum energy of 2.6 eV at room temperature. PL signals in the range of 2.1-2.5 eV can be explained by high-energy transitions in Ge nanocrystals.

Raman spectroscopy technique for analysis of spatial distribution and release kinetics of bioactive substances from bioresorbable polymeric matrixes and particles have been developed and applied. The distribution of hydroxyapatite microparticles in polylactide particles was studied. The release kinetics of ibuprofen from polylactoglycolide matrices of different porosity is analyzed. The dependence of the concentration test substance which released from the polymer matrix on the time of its presence in solution in the range from several hours to several days was studied. The main advantages of the developed methods are the universality of their applicability for studying the structures of various bioactive polymeric composites and their behavior in water-containing media in situ without destroying the analyzed samples, and also the absence of the need for using complex procedures for sample preparation

Phase analysis of solid-state synthesized lithium iron phosphate samples was performed, using Raman spectroscopy. The effect of the probing laser-induced decay of LiFePO4 with the formation of the Fe2O3 phase is demonstrated. Statistical analysis of a series of measurements allowed us to assume the critical nature of this effect.

The possibility of enhancement of Raman intensity of atmospheric nitrogen and oxygen by amplification the electromagnetic field near the surface of a silver diffraction grating is demonstrated. The greatest coefficient of Raman intensity enhancement was about 8 times and was observed under conditions of propagating surface plasmon-polaritons excitation.

During the past decades, one-dimensional carbon allotropes were attracting much interest. One of such modifications consists of the sp¹ chains, ordered in a hexagonal array with nearly 5 angstroms interchain spacing - linear-chained carbon. The technological problem of LCC synthesis is the lack of characterization technique confirming its structure along chains. In this work, we try to improve the simple structural model of chained carbon by adding copper substrate and dopants. We compare the experimental Raman spectra with ones modelled by DFT. The calculation results explain the low-frequency features seen in experimental Raman spectra by the substrate-enhanced interaction of carbon chains.

This paper presents the results of solving the problem of determining the salt composition of multicomponent aqueous solutions by their Raman spectra using artificial neural networks and the method of projections on latent structures. Three methods of input feature transformation are considered: aggregation of adjacent spectral channels, discrete and continuous wavelet transforms. It is shown that all of them can reduce both the dimension of the input data and the error of determination of the salt concentrations in the problem under consideration. The most effective method for the solution of the considered problem was a continuous wavelet transform. The multilayer perceptron trained on the transformed by this method input features provided the average error of determination of concentration for all 5 salts 0.023 M that is 38 % less than the error obtained by artificial neural network used without data compression. Thus, Raman spectroscopy combined with the use of artificial neural networks trained on transformed input features demonstrated high efficiency in solving the problem of identification and determination of concentrations of 5 inorganic salts dissolved in water.

In this paper, the method of artificial neural networks was used to solve the inverse problem of spectroscopy - to determine the concentration of ethanol, methanol, fusel oil, ethyl acetate in aqueous ethanol solutions using spectra of Raman scattering. The following accuracy of concentration determination was obtained: 0.2 % for ethanol, 2.7 % for methanol, 0.4 % for fusel oil, 1.9 % for ethyl acetate. The results of the solution of the inverse problem demonstrated prospects of the proposed methods for the diagnostics of water-ethanol solutions and alcoholic beverages. The obtained results demonstrate the prospects of using Raman spectroscopy in combination with modern methods of data processing (artificial neural networks) for solution of the problems of diagnostics of aqueous ethanol solutions and alcoholic beverages. The proposed approaches can be further used for development of the express non-contact method of detection of harmful and dangerous impurities in alcoholic beverages, as well as for the detection of counterfeit and low-quality beverages.