This paper deals with making a bird dummy for testing the bird-strike resistance of aircraft components. A new bird dummy has been offered. It differs from existing analogs by reproducing the impact impulse with high accuracy. Besides, it is easy to make, store, and clean up its fragments after tests. The bird dummy is made of silicon that models the bird's muscular tissue. It also has plastic ball fillers for modeling the skeleton and the cavities inside the bird. The results of comparative experimental research in strain occurring in a steel target plate and the elements of aircraft transparencies, as well as the damages of an aircraft vertical stabilizer during impact with the dummy and a real bird, are given. Data are presented for different impact angles and velocities. Comparative experiments have shown that using the dummy offered for testing the bird-strike resistance of aircraft components is a viable option. Nomenclature= bird mass M ball = ball mass M d = dummy mass P 0 = pressure of compressed air r = dummy radius r ball = ball radius S b = area of the bird's midlength section S d = cross-sectional area of the cylindrical part of the dummy= strain of steel plate along the x axis ε y = strain of steel plate along the y axis ε 1 , ε 2 , ε 3 = strains for the left-side window of cockpit transparencies ρ = density ρ av = average bird density ρ ball = ball density ρ m = density of a bird's muscular tissue

The paper is devoted to the investigation of antimicrobial activity of polymer nanocomposites of both low-density polyethylene and nonwoven polymeric material (a mixture of woven and polyester fibers) that had been impregnated by Cu nanoparticles. The microorganisms were grown according to generally accepted microbiological rules and on media recommended for each bacteria family. Formation of biofilms of microorganisms was studied on the surface of microtiter plates for enzyme-linked immunosorbent assay. After incubation of microtiter plates, the culture medium was removed from the wells. The wells were rinsed five times with sterile distilled water. The plates were air dried for 45 minutes and each well was stained with 1% crystal violet solution in water for 45 min. After staining, the plates were washed with sterile distilled water five times. The quantitative analysis of biofilm production was done by adding 95% ethanol for discoloration of the wells. The research shows the antibacterial activity of Cu nanoparticles on planktonic forms of the investigated microorganisms, which prevented the formation of dense biofilms. With the use of low-density polyethylene impregnated by Cu the ability to form biofilms by planktonic cells of the referent strains of microorganisms was detected to decrease by 1.7 (Escherichia coli), 12.3 (Klebsiella pneumonia) times in the studied strains and with the use of nonwoven polymeric material treated by Cu nanoparticles, the ability to form biofilms decreased by 1.8 (Escherichia coli) – 21.8 (Klebsiella pneumonia) times in the studied strains. In subjecting the formed daily biofilms of referent strains of microorganisms to Cu nanoparticles, the destruction of biofilms of the studied strains of microorganism was observed as well as violation of the integrity of the biofilm monolayer and decrease of density index in comparison with control values. As a result, the obtained polymer nanocomposites can be recommended for preventive use in the fight against nosocomial infections. The practical relevance of this study lies in the possibility of reducing the incidence of purulent-inflammatory diseases and mycoses and, accordingly, reduction of the costs of treating these diseases.

The results of research on the introduction of a fireproofing agent-polyaminophosphate-during the anionic polymerisation of ε-caprolactam are set out. It is shown that, under certain conditions, the polyaminophosphate can act as a catalyst, which leads to an increase in the degree of polymerisation and to a reduction in the content of residual monomer.

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This work is devoted to the development and study of the processes of accelerated structuring of polymer composite materials in the field of high-frequency current (microwave field) which are used in the electronic and instrument-making industries, etc. The complex of properties and the features of structuring of epoxy, acrylic and epoxy acrylic polymer composite materials in the microwave field are investigated. In comparison with the traditional method of structuring and polymerization (convection heating), the structuring in the microwave field equally affects the properties of the studied polymer composite materials, regardless of the chemical nature of the oligomer. The action of the microwave field for all studied polymer composite materials causes an increase in the degree of conversion of binders and a decrease in the content of residual monomer (methyl methacrylate) in thermoplastic acrylic polymer composite materials. In addition, the microwave treatment provides the completeness of chemical and physicochemical processes of the formation of rational structure of polymer composite materials with stable properties. The conducted research allows recommending various regimes of the structuring of the studied polymer composite materials taking into account operating conditions. These regimes ensure the reduction of structuring duration and provide a high level of mechanical and operational properties.