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Advantages and disadvantages of the fuselage forms of cargo and passenger planes are considered. The research of non-traditional fuselage schemes is presented. The peculiarities of aerodynamics and structural and power scheme of aircrafts, the shape of the fuselage cross-section differs from the round one, influencing its capacity and overall dimensions at the parking on the platform or storage place, are noted.

By methods of modern materials science the analysis of the gradient structure-phase states and nanohardness of hypoeutectic silumin at 120 μm depth after the processing by high intensive electron beams in the regime of top layer melting has been carried out. It has been shown that depending on the depth to the surface of irradiation the electron beam processing leads to the dissolution of the primary inclusions of silicon and intermetallides and the formation of the structure of high-speed cellular crystallization of aluminium and the grains of plate eutectic. A 1.5-2 fold decrease in the concentration of the alloying elements has been detected. The average size of cells by the irradiation surface is 0.4 μm ± 0.11 μm; at the bottom boundary of the layer with the lamellar structure – 0.65 μm ± 0.22 μm. The cell’s volume is formed by the solid solution on aluminium base. In the layer located at the depth of more than 15 μm the formation of submicron grains of lamellar eutectic has been revealed. At 80-90 μm depth the silumin layer in which aluminium melts and the inclusions of silicon and intermetallides of the cast origin retain is detected. In this case the cells of aluminium high-speed crystallization are observable in the structure. The grains of lamellar eutectic of submicron dimensions are absent. At 100-120 μm distance from the surface of irradiation the cellular crystallization structure is not revealed. The hardness of irradiated silumin changes in a nonmonotonous way and reaches the maximum values exceeding the hardness of the initial state by 4 times in the layer located at ≈ 30 μm depth. It has been established that 1.6 – fold increase in the hardness of silumin surface layer is caused by the formation of the high-speed cellular crystallization structure of submicron sizes with the nanodimentional interlayers of the second phase located at the cell’s boundaries. The interpretation of the observed changes in structure and hardness on irradiation has been given., №4 (2018)

Using transmission electron microscopy methods the layer by layer analysis of the bulk hardened superior quality rails is carried out and the quantitative parameters of structure, phase state and defect substructure gradients are established. The gradient character of changing of structure-phase states and dislocation substructure along the cross section of rail head is revealed. The oil bulk hardening of superior quality rails is accompanied by the formation of morphologically different structure, being produced according to the shear and diffusion of γ-α transformation. The base structure volume is formed by the diffusion mechanism and is consisted of plate pearlite grains, free ferrite grains and grains of ferrite-carbide mixture. The presence of the bend extinction contours testifying to curvature-torsion of crystal lattice is revealed on electron microscope images. The analysis of far acting internal field stresses created by interfaces of cementite plates of pearlite grains and interfaces of pearlite and ferrite grains is carried out. It is shown that the interface boundaries globular cementite particles-matrix are the possible places of microcracks initiation.

Electron – beam treatment with 20 J/cm2 energy density of Fe-0.20C-23Cr-18Ni stainless steel increases fatigue life up to 2.1 times. Fracture surface investigations have been carried out by the methods of scanning and transmission diffraction electron microscopy and layer-by-layer analysis of structural phase states and defect substructure of steel subjected to the multicyclic fatigue tests, has been made as well. Nanosize (Cr,Fe)23C6 carbides formation and physical reasons of steel fatigue life increase by electron – beam treatment have been found out. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/34807

The electroexplosive carboborating leads to a significant (up to 12 times) increase in microhardness of the titanium irradiated surface. It is established that the thickness of strengthened surface layer reaches ~ 125 μm. The formation of nanosize structure-phase states in Ti surface layers during electroexplosive carboborating was carried out by methods of scanning and transmission diffraction electron microscopy. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/34804

The quantitative regularities of structure phase states formation in different Hbeam cross sections under accelerated cooling in different regimes are established. The gradient structure-phase states formation being characterized by the regular change of dislocation substructure parameters, nanosized range 􀄮-phase fragments and cementite particles on cross section are revealed by methods of transmission electron diffraction microscopy. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/20687

Based on thefield collectings of S.V.Konovalov, determination of museum collections and analysis of literature data, 45 species of the tephritid flies, belongingto 21 genera are listed; of them eight, Campiglossa misella (Loew, 1869), Chaetorellia acrolophi White & Marquardt, 1989, Euleia heraclei(Linnaeus, 1758), Ictericodes japonicus (Wiedemann, 1830), Oxyna nebulosa (Wiedemann, 1817), Philophylla caesio (Harris, 1780), Tephritisdilacerata (Loew, 1846), Terellia (Cerajocera) nigronota (V. Korneyev, 1985) are recorded for the first time from Lugansk Region. &nbsp