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This study presents the solution of the transient spatial problem of the impact of a moving source of heat flux induced by laser radiation on the surface of a half-space using the superposition principle and the method of transient functions. The solution is based on the Green’s function method, according to which the influence function of a surface-concentrated heat source is found at the first stage. The influence function has axial symmetry and the problem of finding the influence function is axisymmetric. To find the Green’s function, Laplace and Fourier integral transforms are used. The novelty of the obtained analytical solution is that the heat transfer at the free surface of the half-space is taken into account. The Green’s function that was obtained is used to construct an analytical solution to the moving heat-source problem in the integral form. The kernel of the advising integral operator is the constructed Green’s function. The Gaussian distribution is used to calculate integrals on spatial variables analytically. Gaussian law models the distribution of heat flux in the laser beam. As a result, the corresponding integrals on the spatial variables can be calculated analytically. A convenient formula that allows one to study the non-stationary temperature distribution when the heat source moves along arbitrary trajectories is obtained. A numerical, analytical algorithm has been developed and implemented that allows one to determine temperature distribution both on the surface and on the depth of a half-space. For verification purposes, the results were compared with the solution obtained using FEM.

The production of stable and homogeneous batches during nanoparticle fabrication is challenging. Surface charging, as a stability determinant, was estimated for 3-aminopropyltriethoxysilane (APTES) coated pre-formed magnetite nanoparticles (MNPs). An important consideration for preparing stable and homogenous MNPs colloidal systems is the dispersion stage of pre-formed samples, which makes it feasible to increase the MNP reactive binding sites, to enhance functionality. The results gave evidence that the samples that had undergone stirring had a higher loading capacity towards polyanions, in terms of filler content, compared to the sonicated ones. These later results were likely due to the harsh effects of sonication (extremely high temperature and pressure in the cavities formed at the interfaces), which induced the destruction of the MNPs.

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To improve the performance characteristics of modern aerospace systems, research is conducted and expensive programs are being carried out to provide for reducing the weight of the aircraft structure through the use of new, more promising materials, which include the so-called composite materials. Special attention is paid to the dynamic behaviour of composite structures under the influence of high-intensity heat fluxes of various physical nature. The paper considers the dynamic behaviour of composite structures of modern aerospace systems under the influence of high-intensity heat fluxes. As an example, the axisymmetric transverse vibrations of a composite circular plate connected to an elastic base, excited by thermal shock, are investigated. The plate material is modelled with a three-layer composite. To describe the kinematics of an asymmetric plate pack, the hypotheses of a broken normal are accepted. In thin bearing layers, Kirchhoff's hypotheses are valid. In a relatively thick lightweight core, the normal does not change its length, remains rectilinear, but rotates through some additional angle. The base reaction is described by the Winkler model. The statement of the initial-boundary value problem is given. The analytical solution is obtained as a series expansion in terms of eigenfunctions. Its numerical parametric analysis is carried out.