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The paper deals with the results of professional selection of cosmonaut candi-dates by physical readiness in 2019–2020 within the framework of the third open contest. The basis for this analysis was the documented medical fitness certificates of applicants developed according to the results of performing the normative physical exercises by them during the full-time selection stage at “Yu.A. Gagarin R&T CTC” FSBO.

The role of laboratory work in the system of training of engineering and technical specialists is considered. Ready- made stands of FESTO and SMC Pneumatic companies were used, supplemented with new equipment and a physi- cal model of a ventilation unit with an automated control system developed at the department. The importance of laboratory work for the assimilation and consolidation of the material passed, the acquisition of special knowledge and practical skills necessary in production activities is shown.

The article offers a new method to detect brightness edges. It requires no image pre-smoothing and forms a contour image with minimum number of short lines. It is an analogue and, at the same time, an alternative to the widely known Canny border detection method. It differs from it by the method of calculating partial derivatives and by the choice of thresholds in the automatic mode. The processing time of one frame in the proposed method is 3 times less than in the Canny method.

The research of magneto-optical properties has been conducted for the “Nanocomposite-bismuth telluride” (Co40Fe40B20)33.9(SiO2)66.1/[Te3Bi2] multilayer system at various thicknesses of each layer type. We report an enormous enhancement of magneto-optical (MO) response in this system. Besides, a good correlation between thickness dependences of transversal Kerr effect (TKE) and magneto-transport properties has been established. Such correlation was related to peculiarities of the interface forming process at the ferromagnetic (FM) granule boundaries. Moreover, this amplification of magneto-optical response is largest among the other spacer layers, such as Si, Cu, and C, therefore a comparison between them has been plotted.

GaMnAs layers fabricated on GaAs(001) substrates by laser ablation technique were studied using the magneto-optical transversal Kerr effect (TKE) (E = 0.5 - 4.0 eV) and spectral ellipsometry (E = 1.4 - 4.5 eV). Obtained spectral, temperature and magnetic field TKE dependences shown that the used technique allowed us to obtain ferromagnetic (Ga,Mn)As layers, whose composition was close to single-phase one (without MnAs inclusions). Spectral dependences of the off-diagonal components (e’ = e’1 - ie’2) of the permittivity tensor and also of the magnetic circular dichroism (MCD) were calculated for ferromagnetic (Ga,Mn)As sample. The calculated dependences were compared with the published magneto-optical spectra of (Ga,Mn)As layers grown by molecular beam epitaxy.

Transverse Kerr effect (TKE) was used to study magneto-optical (MO) properties of Ni45Mn36.7In13.3Co5 (at.%) single crystals. A single crystalline ingot of such composition was grown by the Czochralski method. One series of samples was quenched into cold water (WQ) and the other series after quenching was heated at 770 K for 20 min and slowly cooled to assure a complete atomic order (SC). Accordingly to differential scanning calorimetry (DSC), magnetic and magneto-optical (MO) measurements, WQ samples exhibit well-defined martensitic transition (MT), but the SC samples do not show MT. It is found that TKE for WQ samples shows the following features (i) MO signal is well pronounced far below the martensitic transition in spite of a weak magnetization of martensitic phase; (ii) the characteristic temperatures of martensitic transition differ from those for the bulk and depend on annealing conditions; (iii) MO spectra profile do not change significantly during the martensitic transition and is similar but not identical with that for Ni50Mn35In15 thin films and Ni43.7Mn43.6In12.7 ribbons measured before; (iv) MO signal is anisotropic.

Work has been carried out to optimise the production of polyamide 6 and layered nanocomposites by anionic polymerisation, during which a layered aluminosilicate is mixed directly with the monomer, catalyst, and activator, and polymerisation of the monomer (oligomer) results in intercalation of the polymer in the interlayer space of the silicate and its subsequent separation into individual sheets (exfoliation). The proposed method represents a rapid way to produce polymer composite materials with high physicomechanical properties.

Magneto-optical spectra of polycrystalline samples of the Fe48Mn24Ga28 Heusler alloy undergoing martensitic transformation from the high-temperature paramagnetic austenitic to ferromagnetic martensitic phase have been studied at 50–320 K in the transversal Kerr effect geometry. A comparison of magnetooptical spectra with data obtained in magnetic measurements has demonstrated that the martensitic transition on the surface of a sample and in its bulk takes place in the same temperature interval. Magnetic anisotropy has been found in the martensitic phase driven by large multidomain inclusions of martensite in austenite. The magneto-optical signal of Fe48Mn24Ga28 differs strongly in spectral shape from that measured in Ni-Mn-Ga.

Optical and magneto-optical properties of GaMnSb layers fabricated on GaAs (001) substrates by laser ablation technique were studied using spectral ellipsometry (E =1.24-3.25 eV) and the transversal Kerr effect (TKE) (E = 0.5 4.2 eV) as well as atomic and magnetic force microscopy. Spectra of the constituents of the diagonal components of the permittivity tensor as well as TKE depended substantially on the layer fabrication conditions. At room temperature a strong resonant band was observed in the TKE spectra for the GaMnSb layers with low Mn content in the energy range E 0.5-1.5 eV. This resonant TKE band was explained by excitation of surface plasmons in MnSb nanoclusters, which arose during the growth of the layers. In the energy region E >1.5 eV the TKE spectra were related to interband transitions in MnSb inclusions.

We report magneto-optical spectra of the Heusler bulk alloys Ni-Mn-In, thin films Ni-Mn-Ga, microwires Ni-Mn-In and Ni-Mn-Ga in martensitic and austenitic states. Transversal Kerr effect (TKE) was studied at an angle of light incidence of 68° with respect to the sample plane, in the energy range 0.5 eV < E < 4.0 eV, at 50 350 K temperatures, and in magnetic fields up to 3.5 kOe. The TKE spectra profile does not change too much at martensitic transformation in Ni2MnGa thin films, only magnitudes of characteristic maxima decrease. The magneto-optical response of Ni2MnGa microwires is very similar to that for Ni2MnGa thin films. For most of studied bulk samples, the TKE signal is very weak (about 10-5), about two orders of magnitude smaller than for thin films, and in many cases could not be detected at all. It indicates the strong dependence of the magneto-optical response of Heusler alloys on the quality of optically or electrochemically polished surfaces and their microstructure.

Spectral and field dependencies of Transversal Kerr Effect (TKE) for [(Co45Fe45Zr10)Z(Al2O3)100-Z(X)/α-Si:H(Y)] n multilayers have been studied in the energy range 0.5 - 4.0 eV. It was found that TKE field dependencies in the nearest IR energy range exhibit anomalous behavior for structures only with thin Si layers and this behavior vanishes with increasing of the Si layer thickness. TKE spectra measured in small and large magnetic fields were essentially different. It was shown that magneto-optical response of multilayered structure composite-silicon is the sum of contributions from two composites: (Co45Fe45Zr10) - Al2O3 + Si + silicides and (Co45Fe45Zr10) - Si + silicides, which have a different sign of TKE in the nearest IR spectrum and their magnetic states depend both on composite and semiconducting layer thicknesses.

Magnetic, magnetooptical and magnetotransport properties of Co 50.3 Fe 20.3 Ti 5.6 Ga 23.8 thin films were studied for the as-prepared as well as annealed samples. Measurements of transv erse magnetooptical Kerr effect revealed that the spectral response of the films strongly depends on the structural ordering which can be manipulated by annealing conditions. Peculiarities in the magnetic properties of the films were attributed to the coexisting phases with different degree of structural disorder. Magnetoresistance of Co 50.3 Fe 20.3 Ti 5.6 Ga 23.8 thin films was found to be linear in the fields above 1 T which is typical for half-Heusler sy stems as well as for Heusler-based ferromagnetic shape memory alloys. Keywords: thin films, Heusler alloys, Kerr effect, magnetoresistance 1. INTRODUCTION X 2 YZ (where X and Y are transition metals, and Z is a main gr oup element) Heusler alloys are a family of intermetallic compounds which has attracted considerable attention over a ce ntury. The interest in the study of these alloys has been conditioned by the fact that they displa y a number of features such as localized magnetic moment behavior, half-metallic properties, properties of topological insulators, attractive thermoelectric properties, giant magnetic field induced strains and a large magnetocaloric effect (see for a recent review Ref. [1]). A single phase L2

In1− x Mn x As (x = 6.9%) layers prepared by ion implantation and subsequent pulsed laser annealing have been studied using the magnetooptical transversal Kerr effect (TKE) and spectral ellipsometry. Ellipsometry data reveal the good crystal quality of the layers. The samples show ferromagnetic behaviour below 77 K. Near the absorption edge of the parent InAs semiconductor, large TKE values are observed. In the energy regions of the transitions in the Γ and L critical points of the InAs Brillouin zone, there are several clearly defined structures in the low-temperature TKE spectra. We have calculated the spectral dependences of the diagonal and nondiagonal components of the permittivity tensor (PT), as well as the spectrum of magnetic circular dichroism (MCD) for our samples. A number of extrema in the obtained MCD and PT spectra are close to the energies of transitions in the critical points of the parent semiconductor band structure, which confirms the intrinsic ferromagnetism of the Mn-doped InAs layers.

The V-A characteristics, with and without an outer magnetic field, the T/sub c/, the phase stability at high temperatures, the oxygen intercalculation capacity in different ambient atmospheres (pO/sub 2/=1 Pa, 4*10/sup 3/ Pa and 2*10/sup 4/ Pa), and the paramagnetic behavior of ceramic samples YBa/sub 2-x/Cu/sub 3/O/sub y/ were correlated with the chemical composition and the applied technology for synthesis of the defect phases. X-ray diffraction, thermogravimetry, electron paramagnetic resonance, and the four-point resistive method were used to study the structure, phase composition, and physical properties of the Ba-deficient YBa/sub 2-x/Cu/sub 3/O/sub y/ phases. Optimal superconducting properties and the lowest contamination of the system were found for the composition YBa/sub 1.95/Cu/sub 3/O/sub y/.

We present a comparative study of the anomalous Hall effect (AHE) and of the transverse Kerr effect (TKE) in the nonstoichiometric alloys. The data on AHE and TKE are consistent with each other and clearly indicate the intrinsic above room-temperature ferromagnetic order in the studied samples. We argue that this order is not produced by the phase segregation effects, but rather has a global character, while even a small level of the nonstoichiometry in alloys drastically changes their magnetic, electrical, optical and magneto-optical properties as compared to those of the stoichiometric manganese monosilicide MnSi. We propose a qualitative explanation of the obtained experimental results in the frame of the model of defect-induced ferromagnetic order using the first-principles calculations of the electronic and magnetic structure of the system.

The authors examine existing and proposed criteria for optimizing gamma spectrometry which have been used in optimal methods for routine multielement analysis of soils and plants by means of 14 MeV neutrons. Optimizing an activation-analysis method amounts to examining a function (optimization criterion) dependent on controlled parameters. The authors considered a mixture of three radionuclides with different half-lives as regards the behavior of the given optimization criteria for one-element analysis in relation to the cooling time.

Five groups of outbred white male rats were given N-nitrososarcosin ethyl ester (NSEE) i.g. for 4 or 6 months at a daily dose of 50 mg/kg of body wt. 5 days/week. Some groups of animals were given a 3% water solution of acetic acid or a 40% solution of ethanol i.g. for 8 months from the beginning of the experiment. The remaining groups of these rats received controlled local thermal burn injury of the esophageal mucosa 15 days before the beginning of the experiment. Acetic acid solution increased the multiplicity of benign and malignant tumors as well as carcinoma incidence in the esophagus. Ethanol in combination with NSEE did not influence carcinogenesis in the esophagus but increased the incidence of leukokeratosis and the multiplicity of forestomach papillomas. In rats treated with NSEE after thermal burn injury, a significant increase in the frequency and multiplicity of papillomas was found in the burn zone.