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According to the Decree of the President of the Russian Federation of January 21, 2020 N 20 "On the approval of the Doctrine of food security of the Russian Federation", the basis for the formation of a national quality management system for food and agricultural products, the main goal of which is to ensure product quality as the most important component of improving health population, improving the quality of agricultural products with the help of modern innovative technologies and feed additives, promoting and stimulating the growth of demand and supply for better food products and ensuring the observance of consumer rights to purchase quality products. Achieving the goals of the Doctrine in the field of improving the quality of food and feed products is supposed to be realized with the help of some tasks, where one of them is the development of the production of food additives and ingredients in the Russian Federation, as well as the development and implementation of a quality management system for agricultural and food products and the creation of conditions for production of new generation products with specified quality characteristics. In this regard, this paper discusses the optimal and economical methods for extracting the dye from the flowers of Clitoria ternatea in order to reduce the duration of the production cycle and the introduction of low-waste technologies, which can exclude the irrational use of raw materials, lead to an increase in production, a decrease in the cost of the finished product, and an increase in economic production indicators, reducing the anthropogenic impact of production on the environment. Also, the work has developed and described a modern technology for the production of a dye, according to which it is possible to improve the quality and safety monitoring system. The prospects of using the dye from Clitoria ternatea flowers in feed additives for farm animals and birds are considered. This can undoubtedly be of interest to the business community, therefore, we can assume that the production of a natural dye from plant materials and this work is a fairly relevant subject within the framework of the Doctrine of Food Security of the Russian Federation, not only from the medico-biological, but also from the technological side.

The co-precipitation of calcium hydroxyapatite Ca10(PO4)6(OH)2 (HA) and natural biopolymer, potassium alginate (PA) [C6H7KO6]n, from an aqueous solution of the CaCl2–(NH4)2HPO4–NH3–[C6H7KO6]n–H2O system (25оC) was used to synthesize HA/PA organomineral composites based on nanocrystalline HA containing 0.1, 0.2, 0.3, and 0.4 wt % PA. The synthesis products were identified by powder X-ray diffraction, thermal analysis, infrared spectroscopy, scanning and transmission electron microscopy, and electron spectroscopy for chemical analysis.

Using the method of diffusion enrichment with a nonsolvent of polymer solutions in mixed solvents, porous structures are obtained and their structural characteristics are determined. Quasi-binary state diagrams of two four-component systems were obtained. Viscosities of polymer solutions in mixed solvents were measured. The dependences of the reduced viscosity on the polymer concentration are obtained. The slopes ratio and the characteristic viscosities are determined. It is shown that the properties of structural elements ([η] and tgα) of solutions differ significantly depending on the composition of the mixed solvent, and that the positions of the regions of heterogeneity in the quasi-binary phase diagrams for the systems under study correspond to these differences. It is shown that significant differences in the sizes of pores and their proportions in the area of ​​the flat section of the structure correspond to the differences in the constitutional diagrams and the degree of nonequilibrium of the structures, which was qualitatively estimated from the value of [η]. The results indicate that the performed viscometric measurements provide useful information in studying the modification of the morphology of condensation structures by changing the composition of the mixed solvent.

The phase structure of synthetic isoprene rubber samples subjected to stretching was studied by transmission electron microscopy. A procedure for determining the fractal dimension of extended one-dimensional structures arising during deformation was proposed. Image parametrization, being the extraction of substantial acting parameters, their description, and quantitative estimation of the obtained parameters, made it possible to characterize each stage of the deformation. A combination of standard methods of studying electron microscopic images using the fractal theory to describe the supramolecular and phase structures of elastomers allows one to understand the mechanism of the deformation process and the nature of the structures arising in structure rearrangement.

Phase equilibria in the mixtures of polyvinyl alcohol (PVA) and chitosan were revealed. Structures of the phases were identified. The temperature and concentration dependences for the chitosan—PVA and chitosan—PVA—water systems were determined. The phase state diagram was built. It is shown that the polymer mixtures are characterized by a complex supramolecular organization, which corresponds to their phase diagram.

The degree of crystallinity of carbon fibers (CFs) of different manufacturers has been determined by means of the Raman scattering method. A gradient “core–shell” model for the CF structure has been suggested. The element composition of CFs has been determined by means of the X-ray electron probe analysis. It has been established that the CF includes oxygen-containing groups, the concentration of which varies from 2 to 4 wt %. A fibrillar structure of the CF shell has been identified via the methods of atomic force probe microscopy and transmission electron microscopy. Longitudinal and transverse sizes of fibrils have been determined. Using the method of low-temperature nitrogen adsorption, the specific surface area, porosity, and pore sizes of CFs have been determined. Isotherms of water vapor sorption by CF within the moisture range from 10 to 95 wt % have been obtained. It has been demonstrated that, for all the studied samples, the sorption isotherms can be approximated using the Dubinin–Radushkevich equation. The sorption capacity of water vapor by CFs has appeared to significantly exceed that of nitrogen, which was associated with the presence of oxygen-containing functional groups.

Cell theory, as formulated by Theodor Schwann in 1839, introduced the idea that the cell is the main structural unit of living nature. Later, in solving the problem of cell multiplication, Rudolf Virchow expanded the cell theory with a postulate: all cells only arise from pre-existing cells. But what did the very first cell arise from? This paper proposes extending the Virchow's law by the assumption that between the nonliving protocell and the first living cell the continuity of fundamental physical properties (the principle of invariance of physical properties) is preserved. The protocell is understood here as a cell-shaped physical system on the basis of the self-organized biologically significant prebiotic macromolecules, primarily peptides, having a potential to transform into the living cell. Biophase is considered as the physical basis of the membraneless protocell, the internal environment of which is separated from the external environment due to the phase of adsorbed water. The evidence is given that the first protocells may have been formed on the basis of intrinsically disordered peptides. Data on the similarity of the physical properties of living cells and the following model systems are given: protein and artificial polymer solutions, coacervate droplets, and ion-exchange resin granules. Available data on the similarity of the physical properties of cell models and living cells allow us to rephrase the Virchow's postulate as follows: the physical properties of a living cell could only arise from pre-existing physical properties of the protocell.

The tracking system of moving objects is analyzed on the basis of a biaxial cardan suspension with MEMS gyroscopes in the control loop. The kinematics of the tracking system in one of the guidance planes is considered. A block diagram of one channel of the tracking system, consisting of correction and stabilization circuits, is given. It is shown that the time of the transition process, the bandwidth, the phase delay between the angular velocity of the accompanied object and the platform is largely determined by the quality factor of the correction circuit speed. The given numerical estimates give an idea of the characteristics of the tracking system. Relations are given that make it possible to estimate the influence of the noise of a MEMS gyroscope on the angular velocity of a stabilized platform. The occurrence of synchronous errors of the tracking system on an oscillating carrier is explained. It is shown that the influence of dry friction forces in the axes of suspension on the tracking system is equivalent to the action of the sum of harmonics with frequencies multiple to the oscillation frequency of the carrier with odd coefficients. The effect of the moment of viscous friction forces in conditions of carrier oscillations is illustrated. An experimental spectral characteristic of the tracking system model on a swinging stand is presented, confirming the theoretical conclusions. An analytical relation is given to estimate the relative synchronous error of the tracking system.

The codeposition of calcium salts, phosphorus, and multiwall carbon nanotubes (CNTs) from aqueous solutions in the Ca(OH)2–H3PO4–H2O–CNT system was used to obtain composite materials based on nanocrystalline calcium hydroxyapatite Ca10(PO4)6(OH)2 (NCHA) and CNTs, containing 0.1, 1, and 5 mass % CNTs. The influence of CNT content on the particle size, morphology, and solubility of NCHA in HA/CNT composite was studied, which models the CNT effect on the process of biomineralization in native calcium phosphates.

The health of student youth, their attitude to healthy lifestyle and bad habits are aspects that are reflected in this article. The urgency of the topic is connected with at least two things: first, with the fact that the problem of low culture of self-preserving behavior is most relevant for young students, including university children; secondly, with the fact that the students' skills of taking care of their health is a prerequisite for preserving the health of the nation, a factor that will affect both the immediate future of the country and the historical prospects of Russia as a whole. The paper presents the initial data of the lognithed sociological survey of students of Novgorod State University, which served as the information base of the article. The authors proceeded from the idea that the institutional environment of the university is a kind of a platform that can be significant in the reproduction of students' health. The paper outlines the nature of the manifestations of individual parameters of self-preserving behavior of student youth and the prevailing trends of reproduction of student’s health. Internal and external social factors that influence the health of student youth over a long period of study (4 years) are analyzed. The dynamics associated with the attitude of different social groups within students to health and bad habits are presented. The information base obtained in the study may later form the basis for the development of practical recommendations and methods to preserve the health of university youth.

A list of tasks, solution of which led to developing and manufacturing a Coriolis vibratory gyroscope working as an angular rate sensor, is given in two designs (CVG-ARS). Orientation, stabilization and navigation systems (OSNS) of medium precision can be created based on the developed CVG-ARS. Parameters of one CVG-ARS are shown along with the design evaluation of OSNS precision.

The paper considers the results of determining the vibrodiagnostic indicators of the presence of various mode I breathing transverse cracks in rod elements of rectangular and circular cross section with different boundary conditions under longitudinal vibrations. Relative second harmonic amplitudes in the vibration spectrum at the main and superharmonic resonance of the first eigenmode of cantilever rods without mass and with a mass at the end and rods with the ends free for longitudinal displacements under forced and kinematic vibration excitation were taken as diagnostic indicators. To determine the above indicators, analytical and numerical bending vibration methods considered before are used. In the analytical solution, the nonlinearity parameter of the vibrating system is calculated using the corresponding values of stress intensity factors. The numerical solution is performed on the basis of eight-node finite element models with the representation of a breathing crack as a mathematical cut and the treatment of a contact problem in the formulation providing mutual nonpenetration between crack faces. Plots of the values of diagnostic indicators as a function of relative crack depth, crack location and the site of measurement of longitudinal displacements have been obtained. Comparisons of values of diagnostic indicators with the value of relative change in natural vibration frequency are presented. It has been shown that at the main resonance, the numerical solution confirms the pronounced effect of localization of diagnostic indicators in the crack region. It has been found that at the superharmonic resonance, the value of the vibrodiagnostic indicator is two orders of magnitude higher than that of the indicators at the main resonance, but the effect of their localization near the crack does not practically manifest itself. Some localization is observed for the absolute values of the second harmonic, and only for longitudinal strain, there is a strongly pronounced effect. A comparison of the obtained values of diagnostic indicators with the data for bending vibrations is given. It is noted that in spite of basically lower indicators under longitudinal vibrations, they have an advantage in terms of the possibility to diagnose symmetric both surface and internal breathing cracks.

Methods for preparing specimens and for processing the results obtained are described. Carbon black of grades T1 and KhS-72, monodispersed polystyrene (molecular weight 200 kDa), polyethylene, polybutadiene rubber, polyisoprene rubber, styrene butadiene elastomer, and butyl rubber were investigated. Two methods were used to prepare filled specimens. In the first case (model systems), the filler and polymer were mixed via a 1–5% solution of polystyrene in toluene. The carbon black content in the suspensions was varied in the range 1–60 wt%. After mixing, the specimens were subjected to ultrasound treatment on a UZDM-2T disperser (44 kHz) for ~10 min. In the second case, sulphur vulcanisates were obtained by the standard procedure. The morphology was studied by transmission electron microscopy (EM-301 electron microscope, Japan) using thin films or etching in high-frequency oxygen discharge plasma on a vacuum reactor (Edwards, UK). A procedure for processing electron micrographs with the aim of obtaining information about local and global fractal dimensions of particle aggregates is described.

The authors discuss a method of approximate calculation of possible values of vibrodiagnostic parameters of the presence of a breathing crack of different crack front configurations (semielliptical, semi-circular, or straight one) in a round bar under super- and subharmonic resonances in a natural bending mode. The calculation of the vibrodiagnostic parameters due to the presence of a crack has been performed through the example of a cantilever bar in the case of the resonance in the first normal mode under force and kinematic excitations. The vibrodiagnostic parameters have been found as a function of the place of the exciting force application, crack location, relative depth and relative area, for different ellipse semi-axes ratios and for cracks with straight or semi-circular fronts. A comparison is made between the calculated results and the finite-element numerical solution data.

Composites comprising micrometer-sized carbon fibers (CFs) and biocompatible nanocrystalline calcium hydroxyapatite Ca10(PO4)6(OH)2 (HA, NCHA), containing 1.0, 2.0, and 5.0 wt % CFs, have been synthesized in the course of precipitation from aqueous solutions in the Ca(OH)2–H3PO4–CF–H2O system. Some physicochemical characteristics of the precursor CFs and synthesis products have been determined using chemical, X-ray diffraction, and thermal analyses, IR spectroscopy, and scanning and transmission electron microscopy. An analysis of composition–synthesis conditions–structure–particle size–property correlations indicates that the presence of CFs in HA/CF composites strongly decreases the sizes and modifies the habit of NCHA. A rise of CF content in the HA/CF composite is accompanied by a decrease in particle size and a rise in solubility of NCHA.

Values of the fractal dimensions, characterising the internal structure and mechanisms of structure formation of dispersed systems, were obtained. The obtained dependences for individual clusters and images as a whole are linear in log–log coordinates. The slope of the dependences varies in the range 1.38–1.82. The obtained dependences can be divided into two groups: for systems with a low filler content (up to 10%) and for systems with a high filler content (over 15%), and accordingly with relatively low (up to 1.5) and high fractal dimensions and different (cluster–cluster and cluster–particle) mechanisms of formation of fractal structures. The influence of radiation dose (7–60 Mrad) on the structure and fractal dimensions of systems was investigated. Using the concept of fractal dimensions, the combined state of carbon black aggregates is described. It is shown that the fractal dimensions of dispersed systems filled with carbon black depend on their preparation and exposure to external effects.

The dynamics of a coriolis vibratory gyroscope with a metal resonator in the free wave mode is considered in the paper. The envelopes of damping oscillations are given for excitation with a different amplitude at the resonant frequency. It is shown that with an increase in the amplitude of excitation, the interval of time to reach the boundary band, at which the signal can be separated from the noise, expands. The nonlinear character of the excitation transfer coefficient of the resonator is established.

The coprecipitation of calcium hydroxyapatite (HA) (Ca10(PO4)6(OH)3) and silk fibroin (SF) from an aqueous solution in the Ca(NO3)2–(NH4)2HPO4–NH3–H2O–SF system has been used to synthesize HA/SF organomineral composites based on nanocrystalline HA, containing 2, 5, and 10 wt % SF. The synthesis products were characterized by X-ray diffraction, thermogravimetric analysis, infrared spectroscopy, scanning electron microscopy, and electron spectroscopy for chemical analysis.

The method of optical interferometry is used to study the interaction of PE with PS in situ. On the basis of the obtained data, phase diagrams of the PE–PS system are constructed for a number of molecular masses of the components. For PE and PS oligomers, the UCMT values are determined. Pair parameters for the interaction of homopolymers are calculated, and their dependences on temperature and molecular mass are considered. The quantitative analysis of the behavior of high-molecular-mass fractions of PE and PS at high temperatures is carried out, and the regions of a partial compatibility of the components are predicted.

Investigations of structure formation in linear and cross-linked polymer systems including one based on xanthan, an exopolysaccharide, attract theoretical and practical interest because of their widespread applications. Freeze-fracture transmission electron microscopy is used to study the structural topology formed in aqueous xanthan solutions and xanthan hydrogels. The data enable us to visualize for the first time an intact structure of xanthan formed in dilute and semidilute solutions at concentrations ranging from 0.002 to 0.5 wt %. In addition to single macromolecules, the dilute xanthan solutions are shown to contain microgels. When the concentration grows to values close to an overlap concentration (C*), a weak gel structure appears, being composed by a continuous 3D network with relatively large meshes. Macromolecular aggregation is observed in the network skeleton when switching to semidilute entangled solutions (>C**); it is accompanied by a compaction of network structure. The cross-linking of polymer chains by polyvalent Cr3+ ions gives a network skeleton composed of aggregated macromolecules at lower concentrations (around C*). Macromolecular aggregation in the skeleton of a network polymer structure occurring both in the absence and in presence of Cr3+ cations is indicative of a microphase separation into polymer-poor and polymer-rich regions.

Features of the method of multiple-operation magnetic monitoring of ferrous impurities in natural and industrial media are identified and ways of improving the method are proposed. A model that involves autonomous exponential extrapolation of an identified second (tail) segment of a mass-operational dependence is constructed. A formula for use in calculating the total masses and mass fraction of ferrous impurities in samples that have undergone magnetic monitoring is found.

Modern macroeconomic situation around political and economic space of Russia is rather complicated and ambiguous. It has a direct detrimental effect on the majority of macroeconomic indicators, including indicators on the labor markets, securities, foreign exchange markets, the standard of living of the population, the pace of social development and welfare, and ultimately on the economy as a whole. These circumstances serve as a catalyst to the top of the reform and transformation of the different segments of the national economy. One of the key elements of reform is an entrepreneurship in the agricultural sector, since in current circumstances it is primary element to ensure food security of the country. Furthermore, this responsibility, on the one hand, contributes to an increase in import volumes, stabilizing activity agribusiness companies and increase their competitiveness, and on the other hand, together with the low financial and economic stability of agricultural units and their functioning, creates a high degree of uncertainty to the activity data subjects. As a result, current macroeconomic conditions only help to increase the risk burden on the activity of subjects of agribusiness, which is already one of the most risky types of economic activity because of its close relationship with poorly predicted climatic factors. Therefore, as one of the current directions of the improvement of the agrarian policy of Russia should be provided for the creation of a specialized methodology for monitoring business risks agribusiness entities, aimed at forecasting, identification, prevention and minimization of risks and their adverse effects, such as the methodology for the moment does not exist. The article presents a developed business risk monitoring methodology agribusiness entities through the budgeting system, providing for a redistribution of funds and resources of the economic entity by creating budgets of various levels and the formation of a dedicated reserve fund to cover unexpected losses related to business risks and their adverse effects.

Cross-linking of polysaccharides by metal ions provides polymer gels highly required by industrial applications. In this article, we study the rheological properties and microstructure of solutions of a stiff anionic polysaccharide xanthan cross-linked by chromium (III) ions, and we demonstrate that their properties are highly sensitive to the preparation pH. Stable gels are obtained in a wide range of pH from 2.4 to 7.8. The maximum elastic modulus is observed for the gels made at pH 6.3, and by freeze-fracture transmission electron microscopy it is shown that they are characterized by the most dense network structure. However, out of this pH interval, no gelation is observed. At low pH (&lt, 2.4) it is due to high protonation of carboxylic groups of xanthan preventing their interaction with chromium ions, and to the disappearance of oligomeric ions, which are effective in cross-linking. At high pH (&gt, 7.8) the absence of gelation is caused by the transformation of reactive chromium ions into insoluble chromium hydroxide. At the same time, for the gels initially formed at pH 6.3, subsequent change of pH to strongly acidic (1.4) or basic (8.9) medium does not affect appreciably their properties, meaning that chromium cross-links are stable once they are formed. These observations open a reliable route to produce polysaccharide gels with required mechanical properties in a wide pH range where they initially cannot be prepared. It is also shown that the increase of pH to 6.3 of the initially ungelled solution prepared at pH 1.5 results in gelation. This effect offers a facile way for delayed gelation of polysaccharides, which is especially required by oil industry.

The paper addresses the methods and results of approximate analytical and numerical calculation of vibrodiagnostic parameters of the presence of a closing semielliptic surface crack in a circular cantilever bar under super- and subharmonic resonances of the lower natural mode of bending vibrations at force and kinematic excitation. The dependences of vibrodiagnostic parameters on crack location and relative depth and on the point of load application are presented. The amplitude-frequency response under the strong superharmonic resonance is shown to differ from those under the weak superharmonic resonance and subharmonic resonance. The reasons why the results of the analytical solution differ from the numerical one obtained by using a finite-element model of the bar have been clarified.

Bi- and trimetallic platinum-ruthenium and platinum-ruthenium-tin catalysts with different atomic ratios of the metals in the surface layer were obtained by deposition of appropriate metal complexes onto highly dispersed carbon black and characterized by X-ray powder diffraction, energy-dispersive X-ray spectroscopy, and transmission electron microscopy. Voltammetric measurements showed that the catalyst PtRu(3: 1)/C provides the highest current densities of methanol oxidation, in agreement with the structural data as well as with the electrochemical and power characteristics of the membrane electrode assemblies tested in single direct-methanol fuel cells.

Nanosized mixed-metal platinum-iron, platinum-anganese and platinum-nickel catalysts supported on highly dispersed carbon black are synthesized by using the corresponding metal complexes with the atomic metal ratio of 1:1. The obtained catalysts are characterized by X-ray phase diffraction and scattering analysis, electron dispersion analysis, scanning and transmission electron microscopy. Thin film rotating disk electrode technique was used to study kinetic parameters of the oxygen reduction reaction at these catalysts. It has been demonstrated that electrochemical activity of the prepared catalysts is comparable to that of a commercial E-Tek platinum catalyst. The membrane electrode assembly (MEA) with the synthesized platinum-iron catalyst was tested in a laboratory hydrogen-air fuel cell setup at room temperature. It was shown that the power performance of this MEA was twice better than that of a MEA on the base of a commercial Pt/C E-Tek catalyst.

The paper summarizes the results of approximate calculation of the influence of amplitudedependent damping capacity of a vibrating system on vibrodiagnostic parameters of the presence of a closing mode I edge crack in a cantilever beam of rectangular cross section for various methods of excitation of the second-order resonance in the lowest natural bending mode.

The paper summarizes the results of approximate calculation of the influence of amplitudedependent dissipation of energy on vibrodiagnostic parameters of the presence of a closing mode I edge crack in beams of rectangular cross-section for different end restrain conditions and different cases of harmonic excitation of subharmonic resonance in any natural mode.

The paper deals with the functioning and analysis of the accuracy of various instruments and systems of orientation, stabilization and navigation on micromechanical gyroscopes (MMG) and accelerometers (MMA). Analytical relations for calculation of errors of the commander of commands of the rotating carrier, strapdown verticals, strapdown inertial navigation system (SINS), system of measuring of vertical rolling of the wave buoy are presented.

The paper considers the task of determining the angular position of the pilot's head with respect to the vehicle body. The task is solved due to the use of two inertial measuring modules, one of which is based on the pilot's head, and the second is rigidly connected to the vehicle body. It is accepted that within some small angles relative to the longitudinal axis of the vehicle, it is possible to correct the readings of the micromechanical system from the optical one. The work analyzes the problems of estimating the errors of the micromechanical positioning system with the aim to increase its accuracy without the correction from the optical system. A method to estimate the errors of measuring modules basing on the use of the quaternion algebra properties is proposed. The proposed method for estimating errors provides for a reduction in computational load in comparison with the method based on the Kalman filter, while maintaining the accuracy of the estimates. Mathematical models of a micromechanical system are presented, as well as the results of the experimental studies of the operation of these algorithms.