Thermo-sensitive water-soluble copolymers based on N-isopropylacrylamide (NIPAAm) and methacrylic acid (MАAc) synthesized by solution polymerization technique with different monomer ratios and azo-bis-isobutyronitrile as an initiator. In order to characterize this synthesized copolymer, an analysis was carried out using various modern research methods. The structure, composition of water-soluble copolymers and homopolymer were studied by FTIR. The thermal properties of the thermosensitive copolymer were studied by thermogravimetric analysis (TGA) and differential scanning colorimetric (DSC) methods. In the thermogravimetric analysis, it was found that the mass loss of the copolymer occurs in two stages and the maximum decomposition temperature (PDTmax). The glass temperature of the NIPAAm-MAK copolymer was determined by the DSC method. The surface morphology of copolymer was analyzed using an optical microscope.

Microstructure and element composition of the sample having the multilayer reactive diffusion zone (RDZ) in Al-Co system obtained by means of contact smelting at 1375 °C for 1 hour were studied in cross-section by means of scanning electron microscopy and electron probe microanalysis (SEM-EPMA). In the multilayer RDZ the following intermetallic compounds CoAl3, Co2Al5, CoAl, β' + (αСо), as well as solid solution of CoAl in (αСо) were identified using the spot energy-dispersion analysis (EDS). Using the methods of linear EDS and wave-dispersion (WDS) analyses the profiles of element concentrations were obtained. These concentration profiles indicate that CoAl3, Co2Al5, CoAl and β' + (αСо) are able to form solid solutions in each other. Microstructural peculiarities of RDZ forming in the layers CoAl3, Co2Al5, CoAl and β' + (αСо) can simulate the actual structural pattern of Al-Co alloys (as-cast).

The article is devoted to the development of a generalized cluster-associated model of the dynamic viscosity of a lead-tin alloy based on the concept of chaotic particles and its relationship with the Frenkel-Andrade viscosity model. In addition to its practical importance, the study of the viscosity of melts of inorganic compounds is also of great scientific interest, since viscosity is the most structurally sensitive characteristic of a substance, which gives an idea of the forces of intermolecular interaction and the mechanism of molecular transport processes in liquids. The accumulation of knowledge in this field allows us to solve many questions related to the theory of the liquid state. The experimental data on the viscosity of melts of inorganic compounds is rather limited, which is explained by the serious difficulties associated with conducting relevant studies. Therefore, it is proposed to use a cluster-associated model for the study of viscosity, which significantly approaches the solution of many problems related to the theory of fluid. The Frenkel-Andrade viscosity model allows us to estimate the yield activation energy. Calculations show that when comparing this energy with the degree of cluster association obtained in the framework of the cluster-association model, a fairly close linear correlation is observed. In this case, the proportionality coefficient makes sense of the activation energy per cluster. This energy does not go beyond the van der Waals energy of the unsaturated intermolecular bond characteristic of the interaction of particles in a liquid.

This scientific work presents the results of a study of the structural features of membranes based on nanoporous alumina using atomic force microscopy (AFM). The capabilities of scanning probe microscopy (SPM), in particular atomic force microscopy, are widely known, but with regard to dielectric materials, the capabilities and advantages of AFM are increasing. The capabilities of AMS with respect to the surface of various nanostructured materials are primarily related to its resolving capabilities. The resolving power of AFM is primarily associated with cantilevers, which are used for surface scanning. In the case of studying the surface of membranes based on nanoporous alumina, the possibilities of AFM and the use of its various techniques are shown. Atomic force microscopy is used to study the surface of various dielectric solid and polymer samples. It is only necessary to select the required AFM technique for surface investigation. You also need to pay attention to the probes that are used for scanning.

This scientific article presents the work on the determination of the moisture content of theoilsand deposits of the Munaili-Mola, Beke, and Dongelek-sor fields were studied. To perform the obtained work, oilsands of Atyrau, Mangistau and Aqtobe regions of Western part of Kazakhstan were used as the object of research. Determination of the moisture content of oil sands were carried out using a drying furnace. Moisture of the oil sands were compared at 106 0C and 150 0C, then dried for 90 minutes. As a result, the indicators for determining the humidity of these oil raw materials at a temperature of 150 0C were higher than the indicators of the corresponding samples at 106 0C. In the process of processing petroleum bituminous rocks by pyrolysis, the amount of moisture contained in it condenses together with evaporated hydrocarbon fractions and completely merges into the collected liquid product, increasing the amount of water in the composition. This is why it is necessary to determine the moisture content of this raw material.

A boundary value problem is considered for the equations of heat and mass transfer when one of the boundary conditions contains normal derivatives of the third order, to which a certain problem of heat and mass transfer in drying processes is reduced. The solution of the boundary value problem is sought in the form of the thermal potential of a double layer. A lemma on finding the limits of the third order normal derivatives is given. Using the boundary conditions, a system of the integro-differential equations (SIDE) with various heat conduction operators is obtained. A characteristic part of SIDE is solved by the method of integrated transformations of Fourier-Laplace when performing a condition of solvability. By the method of regularization of SIDE it is reduced to the system of the integrated equations of Volterra-Fredholm. A theorem of solvability of a boundary value problem is given under the condition of solvability of the heat and mass transfer equations with normal derivatives in the boundary conditions.

This work presents the results of modeling the process of lithium adsorption on the surface of a pristine/defective grapheme sheet 4x4. The study was carried out using the method of computer simulation in the Materials Studio software. The calculations were performed at different degrees of adatom coverage of the graphene surface to determine the effect of these structural changes on the energy and electrochemical characteristics of the presented systems. The work presents models of the studied objects, as well as tables characterizing the energy of adsorption and the magnitude of the transferred charge of Li-C at the smallest distance between the adsorbate and the carbon atom. According to the results of the study, the maximum value of the theoretical specific capacity was 332,727 mAh/g.

The work is devoted to the study of convolutional neural networks for use in the classification of modulated radio signals. Automatic classification of modulation signals has a wide variety of wireless applications. Also shown are modulated radio signals at different SNR levels. In this work, we used data from the DeepSig base of radio modulated signals, created using GNU Radio. Based on this, the classification of modulation using the latest generation convolutional neural networks is considered. The work shows graphs of dependences showing the accuracy of training the network, as well as matrices of inaccuracies with various types of modulated radio signals. It is shown that convolutional neural networks of the latest generation are the most suitable for solving this problem, since they have the ability to quickly learn and accurately determine.

This article presents photometric studies of the cataclysmic variable 2MASS J02253615+2805508, which belongs to nova-like. The light curve is modeled based on the fact that the binary system consists of a primary and secondary star, an accretion material flow, an accretion disk, and a hot spot on its edge. Taking into account the distance to the star taken from the results of the Gaia mission, equal to d=315 (5) pc, some system parameters are obtained, such as the inclination of the system i=77.2°, the masses of the primary and secondary stars, M1= 0.70 Mʘ and M2=0.42 Mʘ, respectively, the radius of the accretion disk Rdisk= 0.58 Rʘ.

The article presents two main problems of integral calculus in their applied aspect, which arouse a lively and continuing interest shown by mathematicians and engineers. The question of the origin of integral calculus is considered, using the example of the problem of calculating areas and the problem of calculating primordial ones. These problems led to two branches of the integral calculus: the theory of definite integrals and the theory of indefinite integrals. Integral calculus is one of the most difficult topics of mathematical analysis, since the process of calculating integrals in general does not lend itself to formal systematization, at the same time it is a powerful tool for solving applied problems. The relevance of the article is primarily in the content disclosure of the basic concepts of the elements of mathematical analysis, in the need for appropriate mathematical support for other disciplines, since the practical application of the integral is mainly used in physics and engineering, as well as in finding the volumes of geometric bodies and in calculating the areas of various shapes. The article is interesting from the point of view of increasing motivation to study higher mathematics in technical specialties. Thus, knowledge of the connection of integral calculus with the needs of practice is necessary for deep assimilation of the theory, the development of specific mathematical thinking, and instilling interest in mathematical disciplines.