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Alexandra Kashchenko, Yaroslavl State University
Izvestiya VUZ. Applied Nonlinear Dynamics, Volume 29; https://doi.org/10.18500/0869-6632-2021-29-6-869-891

Abstract:
The purpose of this study is to construct the asymptotics of the relaxation regimes of a system of differential equations with delay, which simulates three diffusion-coupled oscillators with nonlinear compactly supported delayed feedback under the assumption that the factor in front of the feedback function is large enough. Also, the purpose is to study the influence of the coupling between the oscillators on the nonlocal dynamics of the model. Methods. We construct the asymptotics of solutions of the considered model with initial conditions from a special set. From the asymptotics of the solutions, we obtain an operator of the translation along the trajectories that transforms the set of initial functions into a set of the same type. The main part of this operator is described by a finite-dimensional mapping. The study of its dynamics makes it possible to refine the asymptotics of the solutions of the original model and draw conclusions about its dynamics. Results. It follows from the form of the constructed mapping that for positive coupling parameters of the original model, starting from a certain moment of time, all three generators have the same main part of the asymptotics — the generators are “synchronized”. At negative values of the coupling parameter, both inhomogeneous relaxation cycles and irregular regimes are possible. The connection of these modes with the modes of the constructed finite-dimensional mapping is described. Conclusion. From the results of the work it follows that the dynamics of the model under consideration is fundamentally influenced by the value of the coupling parameter between the generators.
Vadim Muchkaev, Yuri Gagarin State Technical University of Saratov, Anton Onishchenko, Vladislav Tsarev
Izvestiya VUZ. Applied Nonlinear Dynamics, Volume 29; https://doi.org/10.18500/0869-6632-2021-29-6-915-926

Abstract:
Purpose of this work is to study modes and conditions that make it possible to excite the highest type of microwave oscillations, the frequency of which is a multiple of the frequency of the main type, in a monotron with a three-band resonator. Method of the investigation is a numerical 3D modeling, used to calculate the dimensions and electrodynamic parameters of the resonator (characteristic impedance, coupling coefficient, relative electronic conductivity); operation modes of the monotron are considered, which are characterized by excitation of oscillations in the highest type oscillations. Result. In the resonator under consideration, it is possible to achieve a multiple (equal to three) ratio between the frequency of the 25th highest type of oscillations and the frequency of the π/2-type. It was shown that in such resonator simultaneous excitation of electromagnetic field on those frequencies can be made. The maximum of an output power achieved at 100.22 GHz is 15.4 W with an accelerating voltage of 7825 V and an electronic beam microperveance 0.36 µA/V3/2 . The maximal efficiency on a third harmonic is 0.83% while the total efficiency (generating electromagnetic waves of the first and the third harmonics) is up to 17%. Conclusion. It was set that the described method of generation of terahertz range radiation is promising for further investigation, as it solves problem that orthodox microwave devices meet in the millimeter wavelength range, such as small linear dimensions of the components and critical current density of the electronic beam.
Danila Shubin, National Research University ", Higher School of Economics"
Izvestiya VUZ. Applied Nonlinear Dynamics, Volume 29; https://doi.org/10.18500/0869-6632-2021-29-6-863-868

Abstract:
The purpose of this study is to establish the topological properties of three-dimensional manifolds which admit Morse – Smale flows without fixed points (non-singular or NMS-flows) and give examples of such manifolds that are not lens spaces. Despite the fact that it is known that any such manifold is a union of circular handles, their topology can be investigated additionally and refined in the case of a small number of orbits. For example, in the case of a flow with two non-twisted (having a tubular neighborhood homeomorphic to a solid torus) orbits, the topology of such manifolds is established exactly: any ambient manifold of an NMS-flow with two orbits is a lens space. Previously, it was believed that all prime manifolds admitting NMS-flows with at most three non-twisted orbits have the same topology. Methods. In this paper, we consider suspensions over Morse – Smale diffeomorphisms with three periodic orbits. These suspensions, in turn, are NMS-flows with three periodic trajectories. Universal coverings of the ambient manifolds of these flows and lens spaces are considered. Results. In this paper, we present a countable set of pairwise distinct simple 3-manifolds admitting NMS-flows with exactly three non-twisted orbits. Conclusion. From the results of this paper it follows that there is a countable set of pairwise distinct three-dimensional manifolds other than lens spaces, which refutes the previously published result that any simple orientable manifold admitting an NMS-flow with at most three orbits is lens space.
Iuliana Golikova, National Research University ", Svetlana Zinina, Higher School of Economics", Mordovia State University
Izvestiya VUZ. Applied Nonlinear Dynamics, Volume 29; https://doi.org/10.18500/0869-6632-2021-29-6-851-862

Abstract:
It is known from the 1939 work of A. G. Mayer that rough transformations of the circle are limited to the diffeomorphisms of Morse – Smale. A topological conjugacy class of orientation-preserving diffeomorphism is entirely determined by its rotation number and the number of its periodic orbits, while for orientation-changing diffeomorphism the topological invariant will be only the number of periodic orbits. Thus, the purpose of this study is to find topological invariants of n-fold Cartesian products of diffeomorphisms of a circle. Methods. This paper explores the rough Morse – Smale diffeomorphisms on the n-torus surface. To prove the main result, additional constructions and formation of subsets of considered sets were used. Results. In this paper, a numerical topological invariant is introduced for n-fold Cartesian products of rough circle transformations. Conclusion.The criterion of topological conjugacy of n-fold Cartesian products of rough transformations of a circle is formulated.
Ilya Sysoev, Saratov State University
Izvestiya VUZ. Applied Nonlinear Dynamics, Volume 29; https://doi.org/10.18500/0869-6632-2021-29-6-833-834

Aleksandr Kurbako, Saratov State University, Danil Kulminskiy, Ekaterina Borovkova, Anton Kiselev, Victoria Skazkina, Vladimir Ponomarenko, Mihail Prokhorov, Boris Bezruchko, Vladimir Gridnev, et al.
Izvestiya VUZ. Applied Nonlinear Dynamics, Volume 29; https://doi.org/10.18500/0869-6632-2021-29-6-892-904

Abstract:
Purpose of this work is to of the research – Increasing the sensitivity of a method for diagnosing phase synchronization of autogenerators based on their non-stationary time series in real time, and also a comparison of the statistical properties of the proposed modification of the method with the well-known method for diagnostics of loop synchronization, which has proven itself in the analysis of experimental data. Methods.The paper compares the probabilities of the appearance of an error of the second kind of the developed modified method for diagnostics of phase synchronization with the probabilities of occurrence of an error of the second kind of the known method at equal values of sensitivity. When comparing the methods, generated test time realizations with a priori known boundaries of the phase synchronization sections are used, which repeat the statistical properties of the experimental data. It also compares the computational complexity of the two methods. Results. A modification of the method for diagnosing phase synchronization of autonomic regulation circuits in real time is proposed. It is shown that the proposed modification provides similar values of sensitivity and probability of appearance of errors of the second kind as the previously proposed approach. The developed method has less computational complexity than the previously proposed method. The values of free parameters corresponding to different values of sensitivity and probability of appearance of errors of the second kind are obtained. Conclusion. The area of application of the developed method with modification is formulated. The low computational complexity of the proposed method, as well as the possibility of switching devices to integer computations in calculations, makes it possible to use it for wearable registrations performing calculations in real time, based on small-sized low-power processors that do not support floating-point arithmetic operations.
Vasiliy Nechaev, Saratov State University, Elena Rybalova, Galina Strelkova
Izvestiya VUZ. Applied Nonlinear Dynamics, Volume 29; https://doi.org/10.18500/0869-6632-2021-29-6-943-952

Abstract:
The aim of the research is to study the influence of inhomogeneity in a control parameter of all partial elements in a ring of nonlocally coupled chaotic maps on the possibility of observing chimera states in the system and to compare the changes in regions of chimera realization using different methods of introducing the inhomogeneity. Methods. In this paper, snapshots of the system dynamics are constructed for various values of the parameters, as well as spatial distributions of cross-correlation coefficient values, which enable us to determine the regime observed in the system for these parameters. To improve the accuracy of the obtained results, the numerical studies are carried out for fifty different realizations of initial conditions of the ring elements. Results. It is shown that a fixed inhomogeneous distribution of the control parameters with increasing noise intensity leads to an increase in the range of the coupling strength where chimera states are observed. With this, the boundary lying in the region of strong coupling changes more significantly as compared with the case of weak coupling strength. The opposite effect is provided when the control parameters are permanently affected by noise. In this case increasing the noise intensity leads to a decrease in the interval of existence of chimera states. Additionally, the nature of the random variable distribution (normal or uniform one) does not strongly influence the observed changes in the ring dynamics. The regions of existence of chimera states are constructed in the plane of «coupling strength – noise intensity» parameters. Conclusion. We have studied how the region of existence of chimeras changes when the coupling strength between the ring elements is varied and when different characteristics of the inhomogeneous distribution of the control parameters are used. It has been shown that in order to increase the region of observing chimera states, the control parameters of the elements must be distributed inhomogeneously over the entire ensemble. To reduce this region, a constant noise effect on the control parameters should be used.
Nikita Egorov, Saratov Brunch of Kotelnikov Institute of Radioengineering and Electronics of RAS, Vladimir Ponomarenko, Sofia Melnikova, Ilya Sysoev, Marina Sysoeva, Yuri Gagarin State Technical University of Saratov, Saratov State University
Izvestiya VUZ. Applied Nonlinear Dynamics, Volume 29; https://doi.org/10.18500/0869-6632-2021-29-6-927-942

Abstract:
This work aims to show that long transient processes in mesascale models of thalamocortical brain network can appear in very general case, in particular for different number of elements in the ensemble (different level of detalization) and different initial phase of external driving, with these regimes surviving at small variations of number and structure of couplings. Methods. Thalamocortical brain networks are modelled using electronic circuit realized using computer SPICE eluating software. FitzHugh – Nagumo analog generator is used as a single circuit element. Results. Long quasiregular and nonregular oscillation processes with stationary amplitude were shown to occur in ensembles of 14, 28 and 56 model FitzHug – Nagumo generators. The dependency of transient process length on the external driving initial phase and particular coupling matrix structure was studied. Conclusion. The proposed electronic models of thalamocortical system were proved to reproduce the pathological regimes of brain activity in similar way despite the number of elements in the circuit, connectivity matrix and initial driving phase.
Efim Frisman, Matvej Kulakov
Izvestiya VUZ. Applied Nonlinear Dynamics, Volume 29; https://doi.org/10.18500/0869-6632-2021-29-5-706-726

Abstract:
The purpose is to study the mechanisms leading to the genetic divergence, i.e. stable genetic differences between two adjacent populations coupled by migration of individuals. We considered the case when the fitness of individuals is strictly determined genetically by a single diallelic locus with alleles A and a, the population is panmictic and Mendel's laws of inheritance hold. The dynamic model contains three phase variables: concentration of allele A in each population and fraction (weight) of the first population in the total population size. We assume that the numbers of coupled populations change independently or strictly synchronously. In the first case, the growth rates are determined by fitness of homo- and heterozygotes, the mean fitness of the each population and the initial concentrations of alleles. In the second case, the growth rates are the same. Methods. To study the model, we used the qualitative theory of differential equations studies, including the construction of parametric and phase portraits, basins of attraction and bifurcation diagrams. We studied local bifurcations that provide the fundamental possibility of genetic divergence. Results. If heterozygote fitness is higher than homozygotes, then both populations are polymorphic with the same concentration of homologous alleles. If the heterozygotes fitness is reduced, then over time the populations will have the same monomorphism in one allele, regardless of the type of population changes. In this case, the dynamics is bistable. We showed that the divergence in the model is a result of subcritical pitchfork bifurcation of an unstable polymorphic state. As a result, the genetic divergent state is unstable and exists as part of the transient process to one of monomorphic state. Conclusion. Divergence is stable only for populations that maintain a population ratio in a certain way. In this case, it is preceded by a saddle-node bifurcation and dynamics is quad-stable, i.e. depending on the initial conditions, two types of stable monomorphism and divergence are possible simultaneously.
University Saratov, Saratov State University
Izvestiya VUZ. Applied Nonlinear Dynamics, Volume 29; https://doi.org/10.18500/0869-6632-2021-29-5-703-705

Yuri Morozov, Saratov Branch of Kotelnikov Institute of Radiophysics and Electronics of Russian Academy of Sciences
Izvestiya VUZ. Applied Nonlinear Dynamics, Volume 29; https://doi.org/10.18500/0869-6632-2021-29-5-727-738

Abstract:
Most of intracavity pumped optical parametric oscillators (OPO) are made nowaday according to a scheme with a single-resonance OPO located in the cavity of a pump laser. Usually the cavities of the pump and OPO (signal) emission have different values of round-trip time (delay). Aim of the study is therefore to build up the mathematical model of intracavity optical parametric oscillator (ICOPO) considered as a time-delay dynamic system with two values of delay in both cavities (the pump and signal). Methods. The model allows to analyze the steady state (equilibrium point) of the dynamic system and its stability with the help of characteristic equation’s solution. Results. Countless set of the characteristic equation roots is shown to consist of complex-conjugate pairs with imaginary parts which are nearly multiples of intermode beat frequencies in the pump and signal cavities. The diagram of stability depending on the position of nonlinear crystal in the resonator was built on the parameter plane. Features of the plane partition into the areas of stability/instabilty vs behavior of the characteristic equation roots are examined. Discussion. The results of the study allow to consider an ICOPO as the time-delay dynamic system thus adding to the physical picture of intracavity parametric oscillators.
Oleg Maslennikov, Institute of Applied Physics of the Russian Academy of Sciences
Izvestiya VUZ. Applied Nonlinear Dynamics, Volume 29; https://doi.org/10.18500/0869-6632-2021-29-5-799-811

Abstract:
The purpose of this work is to build an artificial recurrent neural network whose activity models a cognitive function relating to the comparison of two vibrotactile stimuli coming with a delay and to analyze dynamic mechanisms underlying its work. Methods of the work are machine learning, analysis of spatiotemporal dynamics and phase space. Results. Activity of the trained recurrent neural network models a cognitive function of the comparison of two stimuli with a delay. Model neurons exhibit mixed selectivity during the course of the task. In the multidimensional activity, the components are found each of which depends on a certain task parameter. Conclusion. The training of the artificial neural network to perform the funciton analogous to the experimentally observed process is accompanied by the emergence of dynamic properties of model neurons which are similar to those found in the experiment.
Aleksandr Kozhevnikov, Saratov Branch of Kotelnikov Institute of Radiophysics and Electronics of Russian Academy of Sciences, Galina Dudko, Yuri Khivintsev, Valentin Sakharov, Sergey Vysotskii, Yuri Nikulin, Michael Seleznev, Aleksander Khitun, Yuri Filimonov, et al.
Izvestiya VUZ. Applied Nonlinear Dynamics, Volume 29; https://doi.org/10.18500/0869-6632-2021-29-5-812-828

Abstract:
Subject. A change in the spectrum of spin waves (SW) in a magnetic cross is investigated when two signals pass through it: a pump signal and a probe signal. Objective. Detection of specific features in formation of the spectra of the output signals of SW in the multiport structure based on a yttrium iron garnet (YIG) film in the case of excitation of two magnetostatic surface waves (MSSW) simultaneously by the input antenna, where the first, with power higher than the first-order parametric instability threshold is the pump, and the second one is a probe. Methods. The experiments were performed for a cross structure from YIG film in the form of two orthogonal waveguides with the SW wire antennas placed at the ends of the waveguides, where one of the antennas on the transversely magnetized waveguide was considered as the input. Result. It was found that by choosing the probing signal frequency, one can significantly (by 10 dB) change the relative signal levels for the satellite waves at the output antennas, which are secondary MSSWs with some new frequencies and appear in the output signals spectrum as a result of the thresholdless processes of merging of parametric spin waves generated by MSSW pumping. In this case the secondary MSSWs frequencies can differ at the output antennas located on orthogonal waveguides. Discussion. The discovered effect is associated with the nonreciprocal nature of propagation of both the pumping wave and the waves generated at parametric instability condition in the structure.
Vyacheslav Tsybulin, Southern Federal University, Toan Dang Ha, Pavel Zelenchuk
Izvestiya VUZ. Applied Nonlinear Dynamics, Volume 29; https://doi.org/10.18500/0869-6632-2021-29-5-751-764

Abstract:
The purpose of this work is to study the influence of various local models in the equations of diffusion–advection– reaction on the spatial processes of coexistence of predators and prey under conditions of a nonuniform distribution of the carrying capacity. We consider a system of nonlinear parabolic equations to describe diffusion, taxis, and local interaction of a predator and prey in a one-dimensional habitat. Methods. We carried out the study of the system using the dynamical systems approach and a computational experiment based on the method of lines and a scheme of staggered grids. Results. The behavior of the predator – prey system has been studied for various scenarios of local interaction, taking into account the hyperbolic law of prey growth and the Holling effect with nonuniform carrying capacity. We have established paradoxical scenarios of interaction between prey and predator for several modifications of the trophic function. Stationary and nonstationary solutions are analyzed considering diffusion and directed migration of species. Conclusion. The trophic function that considers the heterogeneity of the resource is proposed, which does not lead to paradoxical dynamics.
Sergey Glyzin, Yaroslavl State University, Andrey Kolesov
Izvestiya VUZ. Applied Nonlinear Dynamics, Volume 29; https://doi.org/10.18500/0869-6632-2021-29-5-775-798

Abstract:
Nonlinear systems of differential equations with delay, which are mathematical models of fully connected networks of impulse neurons, are considered. Purpose of this work is to study the dynamic properties of one special class of solutions to these systems. Large parameter methods are used to study the existence and stability in сonsidered models of special periodic motions – the so-called group dominance or k-dominance modes, where k ∈ N. Results. It is shown that each such regime is a relaxation cycle, exactly k components of which perform synchronous impulse oscillations, and all other components are asymptotically small. The maximum number of stable coexisting group dominance cycles in the system with an appropriate choice of parameters is 2m − 1, where m is the number of network elements. Conclusion. Considered model with maximum possible number of couplings allows us to describe the most complex and diverse behavior that may be observed in biological neural associations. A feature of the k-dominance modes we have considered is that some of the network neurons are in a non-working (refractory) state. Each periodic k-dominance mode can be associated with a binary vector (α1, α2, . . . , αm), where αj = 1 if the j-th neuron is active and αj = 0 otherwise. Taking this into account, we come to the conclusion that these modes can be used to build devices with associative memory based on artificial neural networks.
Alishir Alifov, Blagonravov Mechanical Engineering Research Institute of RAS
Izvestiya VUZ. Applied Nonlinear Dynamics, Volume 29; https://doi.org/10.18500/0869-6632-2021-29-5-739-750

Abstract:
The purpose of this study is to determine the effect of retarded forces in elasticity and damping on the dynamics of mixed forced, parametric, and self-oscillations in a system with limited excitation. A mechanical frictional self-oscillating system driven by a limited-power engine was used as a model. Methods. In this work, to solve the nonlinear differential equations of motion of the system under consideration, the method of direct linearization is used, which differs from the known methods of nonlinear mechanics in ease of use and very low labor and time costs. This is especially important from the point of view of calculations when designing real devices. Results. The characteristic of the friction force that causes self-oscillations, represented by a general polynomial function, is linearized using the method of direct linearization of nonlinearities. Using the same method, solutions of the differential equations of motion of the system are constructed, equations are obtained for determining the nonstationary values of the amplitude, phase of oscillations and the speed of the energy source. Stationary motions are considered, as well as their stability by means of the Routh–Hurwitz criteria. Performed calculations obtained information about the effect of delays on the dynamics of the system. Conclusion. Calculations have shown that delays shift the amplitude curves to the right and left, up and down on the amplitude–frequency plane, change their shape, and affect the stability of motion.
Aleksandr Funtov, Saratov State University
Izvestiya VUZ. Applied Nonlinear Dynamics, Volume 29; https://doi.org/10.18500/0869-6632-2021-29-5-765-774

Abstract:
Purpose of this work is to construct a theory of extended interaction klystron with ordinary distributed resonators, but with a drift space in the form of medium with complex permittivity. Methods. For this, a hybrid of extended interaction klystron and an amplifier with a complex permittivity is considered in the framework of the weak signal approximation. Two types of configurations of a extended interaction klystron were considered: with two and three distributed resonators. For a two-resonator klystron with distributed interaction, two cases are considered: without reflections from the ends of distributed resonators and the case when the input binder is fully matched to the external transmission line, and for the second distributed resonator, the so-called condition of critical coupling of the “hot” resonator with the transmission line is satisfied. For a three-resonator klystron with distributed interaction, the case is considered without reflections from the ends of distributed resonators. Results and conclusion. According to the results of the developed theory of a weak signal in a extended interaction klystron with ordinary distributed resonators and a drift space with a complex dielectric constant, by choosing the parameters, it is possible to achieve a greater gain at a length that is shorter than in a conventional extended interaction klystron, all other things being equal. In addition, the presence of an intermediate distributed resonator makes it possible to increase the gain while maintaining the full length of the device.
, Kemerovo State University
Izvestiya of Saratov University. New Series. Series: Earth Sciences, Volume 21; https://doi.org/10.18500/1819-7663-2021-21-3-152-158

Abstract:
This article analyzes the current state of space-cartographic research methods and their application in strategic environmental assessment using the example of processing space-cartographic material and its digitalization in order to form a digital management platform that will further allow developing necessary measures for effective environmental management. The basics are briefly outlined and the possibility of using space-cartographic methods to study the state of geoecosystems for solving highly specialized problems in the context of strategic environmental assessment is considered. On a specific example, the main results of these methods application for assessing the geoecological state of the coal-mining areas of the Kemerovo Oblast in the context of strategic environmental assessment are considered.
Izvestiya of Saratov University. New Series. Series: Chemistry. Biology. Ecology, Volume 21; https://doi.org/10.18500/1816-9775-2021-21-3-298-303

Abstract:
Significant researches aimed at the greening of agro-industrial production are focused on obtaining immobilized bacterial preparations with preserved proliferative function and metabolic activity. Herein, we investigated the possibility of bacteria of the genus Azospirillum to be immobilized in Ca-alginate beads. A. brasilense SR80 cells, encapsulated in an alginate hydrogel, were obtained using the “soft” immobilization method based on physical binding. We demonstrated the retained respiratory activity and growth ability of the bacteria during immobilization, thus confirming the advantageous prospects of alginate templates for azospirilla encapsulation.
Artem V. Bogoslov, Saratov State University, , Irina V. Shilova, , Liudmila V. Grebenyuk
Izvestiya of Saratov University. New Series. Series: Chemistry. Biology. Ecology, Volume 21; https://doi.org/10.18500/1816-9775-2021-21-3-328-334

Abstract:
The article presents the results of studying the morphological state of three populations of Delphinium pubiflorum on the basis of quantitative traits measured over four years during the period of mass flowering of plants. The greatest difference in quantitative characteristics was shown by the populations from the Krasnoarmeisky and Tatishchevsky districts of the Saratov region. The differences between the populations are mainly associated with the overall size of the leaves and the quantitative indicators of the axial structure, in particular the length of the generative shoot, as well as the generative sphere – the length of the inflorescence and the number of flowers associated with the latter. In the field, with a visual assessment of the state of the populations, it was noted that plants in the best condition, were those from the Tatishchevsky district. As for the population from the Krasnoarmeisky district, the state of its individuals was the worst.
Yuri V. Preobrazhenskiy, Saratov State University
Izvestiya of Saratov University. New Series. Series: Earth Sciences, Volume 21; https://doi.org/10.18500/1819-7663-2021-21-3-159-165

Abstract:
Identifying the spatial structures of economic activity within a supra-regional entity is an urgent scientific task. In this study, it is solved using a combination of a framework approach and a model analog of the gravitational interaction for the cities of the Volga-Ural macroregion. According to the cost of industrial production of cities with a population of more than 100 thousand inhabitants (i.e., the first and second cities of their regions) and the distance between them, an industrial-urbanized framework of the macroregion was built, demonstrating the potential of economic ties within it. The analysis of the strength of ties allowed us to identify the peripheral and central cities-industrial centers. Among the first ones there are the cities of Orenburg and Penza regions, among the second ones – Ufa, Samara and Tolyatti. In addition, the functions of the second cities of the regions were analyzed and the degree of industrial orientation of the first and second cities of the macroregion was revealed.
, Saratov State University,
Izvestiya of Saratov University. New Series. Series: Chemistry. Biology. Ecology, Volume 21; https://doi.org/10.18500/1816-9775-2021-21-3-260-266

Abstract:
Test means based on immobilized Fehling’s reagent for the determination of cephalexin have been obtained. Methods for visual and colorimetric assessment of antibiotic concentration using a smartphone camera have been developed. The optimal conditions for the indicator reaction have been selected with varying heating time and temperature. For a visual semi-quantitative assessment of the content of cephalexin, a color scale has been obtained. The metrological characteristics of the test method have been determined: the range of the determined contents is 0.5–16 mg/ml, the unreliability interval is 0.1–0.4 mg/ml, and the detection limit is 0.4 mg / ml. For the colorimetric assessment of the concentration of cephalexin, a linear dependence of the intensity of the Blue channel on the logarithm of the concentration of cephalexin (у = –96x + 144, r 2 = 0.99) has been constructed, and linear dependences of the area (у = –36986x + 62458, r 2 = 0.96) and perimeter (у = –270x + 786, r 2 = 0.93) from the logarithm of the concentration of cephalexin have been obtained. The range of the determined contents was 0.1–16 mg/ml, the lower limit was 0.1 mg / ml. The verification of the correctness of the developed test methods was carried out by the «introduced-found» method (Sr  0.13).
Svetlana V. Borisova, Saratov State University,
Izvestiya of Saratov University. New Series. Series: Chemistry. Biology. Ecology, Volume 21; https://doi.org/10.18500/1816-9775-2021-21-3-254-259

Abstract:
A series of novel spirooxindoles have been synthesized through three-component 1,3-dipolar cycloaddition of azomethine ylides generated in situ by the decarboxylative condensation of isatin and sarcosine with the dipolarophile 3-phenyl-1-(heteroaryl -2-yl)prop-2-en-1- one, synthesized by the Knoevenagel reaction using 2-acetylfuran, 2-acetylpyrrole, 2-acetylthiophene and substituted benzaldehydes. These compounds are used for the first time as dipolarophiles. This method has the advantages of mild reaction conditions, high atom economy, excellent yields, and high regio- and stereo-selectivity. The reaction was carried out by mixing equimolar amounts of enone and isatin, as well as a slight excess of sarcosine in isopropyl alcohol when heated to 60–70°C. Among the enones with various heterocyclic substituents, it is most convenient to use compounds containing a pyrrole fragment as dipolarophiles, since the products are obtained in a short amount of time in good yields. The use of enones obtained from 2-acetylthiophene leads to an increase in the reaction time, and from 2-acetylfuran - to a significant resinification of the reaction mixture. The structures of the compounds obtained were proved using a combination of 1H, 13C NMR spectroscopy data, as well as two-dimensional NMR experiments of heteronuclear correlation, HSQC and HMBC. Based on the data obtained, a mechanism for the formation of products has been proposed.
Victoriya S. Rastegaeva, Saratov State University, Ekaterina V. Pleshakova
Izvestiya of Saratov University. New Series. Series: Chemistry. Biology. Ecology, Volume 21; https://doi.org/10.18500/1816-9775-2021-21-3-304-308

Abstract:
In today’s modern technogenic world, forming an ecological consciousness, perception and thinking among schoolchildren is a vital task. Knowledge of chemical toxicology is essential for students of all ages to help protect and maintain a healthy environment. Given that toxicology is characterized by an increased level of complexity, the purpose of this work was to develop and apply gaming methods in teaching the basics of chemical toxicology as part of environmental education of schoolchildren. We developed and implemented a training lesson for schoolchildren called “Fascinating phytotoxicology” for secondary school students, which consists of several stages. At the first stage, when using explanatory and illustrative methods in teaching, students received theoretical knowledge of phytotoxicology; at the second stage, students enhanced their knowledge in a playful way by solving situational problems composed by us, guessing riddles and answering intriguing questions; at the third stage, a survey was conducted among schoolchildren to identify the students’ level of interest in the topic and how much of the material was assimilated. The survey showed that the implementation of this gaming teaching method allowed students to learn complex material better, increased the activity and interest of students, and also contributed to the formation of an ecological awareness and environmental responsibility.
, Institute “Microbe” of Rospotrebnadzor, Alexander Yu. Ul’Yanov, Ruslan R. Salikhov, , Natalia G. Avdeeva, Yulia I. Samokhvalova, Oksana A. Volokh
Izvestiya of Saratov University. New Series. Series: Chemistry. Biology. Ecology, Volume 21; https://doi.org/10.18500/1816-9775-2021-21-3-317-323

Abstract:
Environmental pollution with industrial waste is an urgent problem today. A special place in the list of pollutants belongs to waste from biotechnological enterprises and industries, whose activities are related to the production of various drugs. Russian Research Anti-Plague Institute «Microbe» is the only manufacturer of unique immunobiological drugs in the Russian Federation – bivalent chemical cholera vaccine and rabies immunoglobulin from horse blood serum (AIG). At present, the institute actively uses fibrin as a basis for nutrient media – a waste in the production of AIG; a technology for the regeneration of alcohol waste has been developed; biologically active substances were obtained from the production waste of specific components of the cholera vaccine. The aim of the work was to assess the prospects of using waste products from the production of specific components of cholera vaccine (cholerogen-toxoid – X-AT, and O-antigen – O-AG) – formalized detoxified microbial-free filtrate (FMF), as a nutrient medium for the cultivation of industrial strains of microorganisms. It has been shown that the best methods for reducing formalin concentration are autoclaving and chemical neutralization with aqueous ammonia. During low-volume cultivation of Vibrio cholerae 569B and V. cholerae M-41 strains on all variants of experimental media based on PBP, an increase in biomass was noted. The production of Vibrio cholerae antigens at a level comparable to that of growing on a control nutrient medium was recorded in a medium variant based on O-AG production waste. The use of FMF as a nutrient medium in the future will reduce the volume of waste generated and reduce the load on the treatment facilities of the Institute, which will increase the environmental safety of production.
, Saratov State University
Izvestiya of Saratov University. New Series. Series: Philosophy. Psychology. Pedagogy, Volume 21; https://doi.org/10.18500/1819-7671-2021-21-3-242-246

Abstract:
The article is devoted to the question of being in Heidegger’s fundamental ontology, namely, his claim to understand the ancient idea of being. In his work “Contributions to Philosophy (From Enowning)”, Heidegger distinguishes between the understanding of being as the being of everything that exists and his own understanding of being as such, out of connection with things. He calls the first point the “leading question” and attributes its authorship to Aristotle, the second one – “the main question”. The article discusses the relationship of these issues, the possibility of their formal coincidence and discrepancy between them. The first part of the article introduces the context of Heidegger’s thought. It deals with the “ontological difference” that Heidegger introduces in the framework of “Being and Time”, as well as with what transformation this difference undergoes in his later works, after the “turn” (“Kehre”). In the second part of the article, attention is drawn to the convergence and divergence of the “leading question” from the “main one” by clarifying the ontology of Aristotle. Particular attention is paid to various ways of understanding existence, in particular – an incidental and accidental existence. At the end of the article, the attempt will be made to reconstruct the direction of Heidegger's thought, based on the results of consideration achieved earlier.
, Lomonosov Moscow State University
Izvestiya of Saratov University. New Series. Series: Philosophy. Psychology. Pedagogy, Volume 21; https://doi.org/10.18500/1819-7671-2021-21-3-247-251

Abstract:
The concepts of contingency, factuality, and correlationism introduced by Meillassoux are clarified in the article. The question of the contingency of the forms of correlation is revealed in the context of the functioning of post-Kantian philosophy. The contingency of the correlationist theories of a subject is established. The article substantiates the thesis about the dual position of the subject in the factual ontology: Meillassoux reaches the antisubjectivist contingency through a radical overcoming of the various paradigms of the subject, then, the philosopher recovers the position of a strong subject from the non-human contingency. Basically, the article deals with the ontological status, characteristics and factual ethics of the vector subject. It reveals the way in which Meillassoux thinks of the subject in the context of the radical unreasonableness: this is the simultaneous holding, on the one hand, the order of the actual given and, on the other, the contingency of the given and the subject. The factual character of the subject-object dichotomy restored by Meillassoux is clarified. It’s established that non-Hegelian dialectics is the main manner of navigating the subject in the contingent universe. The key property of the subject, its “vectorness”, is determined. The main characteristics of the actual and virtual World are highlighted. Furthermore, it’s investigated how the subject is activated in the direction of the virtual World. It’s noted that the thinking of the vector subject is more focused on temporality than on space. The ontological foundations of the “spiritual exercises” prescribed to the vector subject are analyzed.
, Saratov State University, Khristina A. Vysotskaya
Izvestiya of Saratov University. New Series. Series: Philosophy. Psychology. Pedagogy, Volume 21; https://doi.org/10.18500/1819-7671-2021-21-3-326-333

Abstract:
This research is a response to topical objectives of studying adjustment abilities of human psyche in the situations of global uncertainty and potential threat to human life. The research is aimed at the insight into the ways of coping with lockdown during COVID-19 pandemic. The goal was achieved within the positive approach employed to find psychological resources that encourage successful and subjectively satisfactory solution to a difficult life situation. The research is based on the author’s psychological questionnaire with the use of quantitative scale of subjective assessment. The questionnaire helped gather information about the influence of lockdown on the psychological well-being and about the changes in human character and behavior. The study involved 306 people (246 women and 60 men) aged 18 to 67. The authors revealed that satisfaction with one’s well-being during lockdown positively correlates with the ability to see positive aspects of a situation, with learning new methods of self-regulation, with new interests, with encouraging one’s own creativity and sense of humor, with willingness to enjoy opportunity to finish things that were once postponed, with aspiration to understand oneself and other people and to experience the sense of unity with the whole world.
Anna O. Kondratieva, Saratov State University, ,
Izvestiya of Saratov University. New Series. Series: Chemistry. Biology. Ecology, Volume 21; https://doi.org/10.18500/1816-9775-2021-21-3-342-346

Abstract:
The results of studying the spatial-ontogenetic structure of five cenopopulations of Globularia bisnagarica L. on the territory of the Orenburg region and the Republic of Tatarstan are presented. Analysis of the age structure using the OntoParam program algorithm revealed the heterogeneity of ontogenetic spectra in most cenopopulations. Assessment of the parameters of average age, recovery index and ageing index showed that most cenopopulations are capable of self-restoration and maintenance of numerosity. Analysis of spatial structure taking into account the ontogenetic state of individuals showed that the spatial relationships between pregenerative and generative individuals is random in most cases, which indicates the absence of any pronounced interactions between plants from these age groups. In the cenopopulation from Severny district of the Orenburg region, there is a slight sparseness in the mutual arrangement of pregenerative and generative individuals, which may be due to the influence of intraspecific competition.
Sofya I. Pryakhina, Saratov State University, Anna A. Kotova
Izvestiya of Saratov University. New Series. Series: Earth Sciences, Volume 21; https://doi.org/10.18500/1819-7663-2021-21-3-166-168

Abstract:
The article presents the results of work on the study of synoptic conditions for the formation of a dangerous weather phenomenon for the territory of Western Siberia – a thundersnow. The material for the study was the archive of aerosynoptic material from the Khanty-Mansiysk Air Meteorological Center.
Izvestiya of Saratov University. New Series. Series: Philosophy. Psychology. Pedagogy, Volume 21; https://doi.org/10.18500/1819-7671-2021-21-3-349-353

Abstract:
The article deals with the problems of implementing the project-based learning method in professional education. The aim of the study is to identify the key factors hindering the full use of the method in educational practice. The research methodology is based on a systematic approach and includes methods of description, comparison, comparative analysis, and generalization. The project-based learning method fully meets the objectives of the competence-based approach in professional education. For a number of areas of training, the project-based training method is also significant in that it allows you to demonstrate the formation of graduate competencies to a potential employer. This is mainly reflected in the results of project activities. The positions of subjects interested in the results of the educational process are formulated. The adoption of the project-based learning method by participants in the educational process – students, teachers, and University administration – is hindered by negative motivation, which clearly prevails in the short term. It is concluded that for the actual, real, and not formal transition to the use of the project-based learning method, measures are needed not to be imposed by the state, but to stimulate participants of the educational process.
Olga F. Filimonova, Yuri Gagarin State Technical University of Saratov
Izvestiya of Saratov University. New Series. Series: Philosophy. Psychology. Pedagogy, Volume 21; https://doi.org/10.18500/1819-7671-2021-21-3-298-303

Abstract:
Despite the fact that social changes are often proclaimed as a combination of positive development prospects, in practice they will not necessarily lead to positive results for everyone and in general. The sociological, ontological and cultural essence of modern changes in the mode of unreliability and redundancy of security systems is revealed. The horizon of understanding the problem in the mode of transition to a new technological order, which requires individual adaptation of people to a risk-generating environment, to a society without guarantees, is proposed. The concepts of “the lack of protection” and “the culture of control” are the basic part of the content. It has been established that digitalization is not substantial, but epiphenomenal, and that the culture of control is an imperative of digitalized sociality and dehumanization. The lack of protection is a sign of transition to the metric rationality of the culture of control, which increases the inanity of the forms and meanings of human existence simplifying it to an adaptation formula. The nature of the lack of protection is not metric, but an internal process that leads away from the adaptive logic of protection to the depth of understanding the limits of its probability in practice. The quality of this level of reflection is not determined by the pressure of changes, but is formed in the creation of thought and the upbringing of will within the social whole.
, Ugra State University
Izvestiya of Saratov University. New Series. Series: Philosophy. Psychology. Pedagogy, Volume 21; https://doi.org/10.18500/1819-7671-2021-21-3-304-308

Abstract:
The article, based on the presented empirical material, reveals the problem of professional self-attitude and its types among teachers with different levels of expression of conscious self-regulation. The study covered 157 teachers of comprehensive schools of the Khanty-Mansiysk Autonomous Okrug – Ugra. The age of the examined is from 31 to 45 years. We used the technique “Attitude to yourself as a professional” and the questionnaire “Style of self-regulation of behavior”. On the basis of the obtained results, it was proved that the processes of conscious self-regulation are interconnected with the magnitude of activity and positivity of professional self-attitude of teachers, as well as that subjects with different levels of self-regulation (high, medium and low) differ in the dominant types of attitudes to themselves as a professional. It has been shown that the more developed regulatory processes are, the more active and positive the professional self-presentation of teachers is – a higher level of claims, combined with a positive representation and acceptance of a professional, expressed by the installation on professional self-development. It was revealed that teachers with a low level of self-regulation are distinguished by a passive-negative attitude towards themselves as a professional, while teachers with a high level are characterized by an active-positive attitude towards themselves, with the dominance of positivity, and teachers with an average level of self-regulation have a pronounced balanced professional self-attitude. It has been established that for the regulatory process of “programming”, the installation on professional self-development is of leading importance, while for the regulatory process, “flexibility” is a significant indicator - the idea of oneself as a professional.
, Southern Federal University, Alexandra G. Berezhnaya, ,
Published: 24 September 2021
Electrochemical Energetics, Volume 21; https://doi.org/10.18500/1608-4039-2021-21-3-156-163

Abstract:
The electrochemical properties of C/MnO2 composite materials in 1 M sodium sulfate solution were investigated using the methods of cyclic voltammetry, galvanostatic charge-discharge and impedance spectroscopy. It was shown that the capacitive characteristics of the electrodes depend on the nature and the method of obtaining manganese oxide nanoparticles. It was established that the material containing manganese oxide obtained using isoamyl alcohol as a reducing agent has high electrochemical characteristics.
Viktor I. Panov, Psychological Institute of the Russian Academy of Education, , ,
Izvestiya of Saratov University. New Series. Series: Educational Acmeology. Developmental Psychology, Volume 10; https://doi.org/10.18500/2304-9790-2021-10-3-188-196

Abstract:
The relevance of the problem of adolescent behavior in the digital educational environment is conditioned by acceleration of education digitalization processes, which participate in the formation of a new type of behavior, i.e. digital behavior, that is defined as a system of actions associated with the use of the digital environment. The purpose of the present work is to investigate the current state of this problem and outline the prospects for its further study on the basis of the analysis and generalization of Russian and foreign sources. We employ the methods of theoretical analysis, systematization of the results of relevant psychological and pedagogical studies and the retrospective analysis of key concepts. We also present the general conceptual system of the research area under study and the genesis and semantics of the terms: information behavior, digital behavior, educational environment, digital educational environment (DEE). The study has revealed the process of transformation of views on the educational environment and the difference between the digital environment and the pre-digital one. The problem area of DEE study has been indicated: positive and negative effects of DEE implementation, psychological reasons for rejecting innovations, psychological safety of the educational environment and design of the effective DEE. We have also investigated the problem of full scale use of digital educational platforms and services in Russian schools to improve the quality of the learning process, including distance learning. We have considered the sources and methods of researching digital behavior, i.e. digital psychometrics based on the analysis of “digital footpri nts”. Unlike most works that study deviant behavior of adolescents, our work focuses on normative, pro-social behavior. We have taken into consideration such problems as behavior of schoolchildren on different digital educational platforms, digital multitasking, interaction of adolescents with electronic text content, stages of subjectivity formation in the digital educational space, which are relevant for the study.
Alfiya R. Vagapova, Saratov State University
Izvestiya of Saratov University. New Series. Series: Educational Acmeology. Developmental Psychology, Volume 10; https://doi.org/10.18500/2304-9790-2021-10-3-275-278

Abstract:
It is an issue of great importance and necessity to study phenomenology of modern people’s social activity within the context of perceiving it as a source of transformation of oneself and of society as a whole. Changes in certain forms of manifestation of social activity, as well as the locus of its orientation are conditioned by the interaction between many factors pertaining to multi-level order, which are integrated into the dynamic regulatory-functional system, reveal peculiarities of social changes, and, at the same time, reflect the general socio-historical context. The monograph written by a group of authors (R. M. Shamionov, M. V. Grigoryeva, I. V. Arendachuk, E. E. Bocharova, N. V. Usova, M. A. Klenova, A. A. Sharov, A. I. Zagranichny) presents the results of theoretical and empirical studies of the phenomenology, mechanisms and factors of young people’s social activity according to provisions of the system-diachronic approach, which is being actively developed by Professor R. M. Shamionov’s scientific school. Varied empirical material helps to establish some facts that indicate contradictory trends of functional manifestation in the development and limitations of certain social activity forms in various life spheres, depending on the social and age status of an individual, conditions and stages of socialization, as well as the context of real and virtual environment. The team of authors made an attempt to develop and validate the tool for ev aluating a person’s adherence to various forms of social activity (R. M. Shamionov, I. V. Arendachuk, E. E. Bocharova, et. al.) and its components (R. M. Shamionov, M. V. Grigoryeva); to adapt and validate the questionnaire published in the English language called CYBA (Cyber-aggression Questionnaire for Adolescents, D. Álvarez-García, A. Barreiro-Collazo, J. C. Núñez, A. Dobarro) on the Russian-speaking sample (A. A. Sharov), which allowed to record destructive practices of social activity, which were implemented in the virtual environment. The team of authors would like to express hope that the monograph can serve as a tool to clarify some of the aspects of social activity and social behavior of modern young people and can be useful for students and graduate students, whose academic work is related to young people’s social activity.
Anna A. Golovanova, Saratov State University,
Izvestiya of Saratov University. New Series. Series: Educational Acmeology. Developmental Psychology, Volume 10; https://doi.org/10.18500/2304-9790-2021-10-3-279-280

Abstract:
The article provides information on the forthcoming international scientific conference “Strakhov Readings – 2021”, which will be held on November 11–12, 2021. The conference continues the tradition of holding annual Strakhov Readings in memory of the founder of Saratov Psychological School, the first head of the Department of Psychology of Saratov State Pedagogical Institute, Professor I. V. Strakhov.
, Saratov State University
Izvestiya of Saratov University. New Series. Series: History. International Relations, Volume 21; https://doi.org/10.18500/1819-4907-2021-21-3-365-378

Abstract:
The article analyzes the mediation activities of international organizations in the Nagorno-Karabakh conflict from 1992 to 2020. The positions of the OSCE, the United States, Russia, as well as Armenia, Azerbaijan and Nagorno-Karabakh regarding the plans for a peaceful settlement of the conflict are examined. The key role of the Russian Federation as a major regional factor in the reconciliation of the warring parties and the resolution of the Nagorno-Karabakh problem is considered.
, Samara National Research University, Nadezhda N. Kabytova
Izvestiya of Saratov University. New Series. Series: History. International Relations, Volume 21; https://doi.org/10.18500/1819-4907-2021-21-3-410-415

Abstract:
The review presents an analysis of V. V. Kondrashin’s textbook, which, on the basis of a large complex of archival and published documentary materials and scientific literature, recreated a panorama of the relationship of the Russian peasantry with the opposing power structures that appeared and functioned in Russia during the Great Russian Revolution – the Bolshevik government and its political opponents that arose during the Civil War, white and other regimes. It is noted that the author paid special attention to the conceptual views of Soviet, Russian and foreign historians, which made it possible to gain new knowledge about the practices of the behavior of peasants in various regions of Russia during social conflicts – uprisings and other protest actions and to trace their attitude to the agrarian policy of the Soviet government, as well as the governments and leaders of the white movement. Factors that influenced the choice of the Russian peasantry were identified – support for the Soviet government, which ensured its victory during the Civil War.
, Saratov State University
Izvestiya of Saratov University. New Series. Series: History. International Relations, Volume 21; https://doi.org/10.18500/1819-4907-2021-21-3-330-336

Abstract:
The article discusses the sources of income, expenses and methods of doing business in the aristocratic Lisle`s family. Based on the correspondence of the Lisle`s spouses with their managers and financial agents, it is revealed that the greatest income for the family came from the lease of land, extraction of tin, timber and the fish trade. The position of governor of Calais, held by Lord Lisle, also brought income. However, the expenses of the family associated with caring for the manors, the need to endorse the status of an aristocratic family, the costs of maintaining and educating the children, as well as endless litigation over land ownership, significantly worsened the financial situation of the family. The author concludes that, despite the various sources of income and the very impressive amounts obtained from them, the Lisle family permanently needed money, for this reason Lady Lisle was forced to look for new ways to replenish the family budget.
Yuriy V. Varfolomeev, Saratov State University
Izvestiya of Saratov University. New Series. Series: History. International Relations, Volume 21; https://doi.org/10.18500/1819-4907-2021-21-3-416-419

Abstract:
The review analyzed the characteristics and content of a unique ego-source, the memoirs of a prominent figure in the revolutionary movement of late Imperial Russia S. A. Nikonova, on the pages which come to life fragments of revolutionary struggle and cultural-public life of Russia at the turn of the twentieth century, and presents a gallery of historical portraits and sketches prominent and often little-known characters of that era. The reviewer pays special attention to the evaluation of the scientific and publishing work on the preparation of this publication, done by Associate Professor V. A. Solomonov.
, Saratov State University
Izvestiya of Saratov University. New Series. Series: History. International Relations, Volume 21; https://doi.org/10.18500/1819-4907-2021-21-3-359-364

Abstract:
The article is devoted to studying the process of theoretical development and practical implementation of the plan for integrating the region of South and Southeast Asia into the U. S. strategy for restoring world trade, which is called the «Marshall plan for Asia» or AFAP. The Eisenhower administration’s desire to use the Cold War context to secure funding for the program from the U. S. Congress is emphasized. The reasons for the failure of the plan are analyzed, related to the contradictions between the countries of the region under consideration, as well as their fears of losing bilateral assistance from the United States.
, Ivanovo State University of Chemistry and Technology
Izvestiya of Saratov University. New Series. Series: History. International Relations, Volume 21; https://doi.org/10.18500/1819-4907-2021-21-3-353-358

Abstract:
The article is devoted to the study of the role of music and sound effects in the Anglo-American cinematograph. An attempt is made to assess the political and symbolic potential of media resources for representing the «image of another». To this end, the author examines a number of specific films created at different stages of the Cold War. Conclusions are made about the use of the following methods of media construction: noir representation, political-satirical spectrum, modes of address-local or mixed/combined borrowing of compositions, imitation of a «different» culture.
Izvestiya of Saratov University. New Series. Series: Earth Sciences, Volume 21; https://doi.org/10.18500/1819-7663-2021-21-3-169-178

Abstract:
The development of the geosystems of the Russian Far East proceeds under the enormous but contradictory in nature double influence of the continent and the ocean and is carried out through the atmosphere. The goal is to characterize hazardous natural phenomena depending on the differentiated natural tension of the Far East (from maximum in the south to moderate in the north), often causing disasters and creating tense levels of the geoecological situation in general. The article presents comparative-geographical, geophysical, informational methods, as well as author’s development, etc. Further strengthening of the natural continentality of the entire region climate predetermines a directed increase in the geosystems development of the role of hazardous natural processes. If a sharp anthropogenic climate warming occurs, an accelerated rise in the level of the World Ocean is possible, which will cause increased abrasion, avalanches and landslides in the coastal zone. In case of a persisting general cooling, a general extremalization of the entire natural environment will occur. Crisis situations are, to a certain extent, predictable, which can help in optimizing rational nature management.
Elmira I. Tsygulyova, Saratov State University,
Izvestiya of Saratov University. New Series. Series: Chemistry. Biology. Ecology, Volume 21; https://doi.org/10.18500/1816-9775-2021-21-3-267-273

Abstract:
For the efficient preconcentration of azo compounds – products of the interaction of 4-nitrophenyldiazonium with thymol, a system 4-nitroaniline (4-NA) – NO2- – Triton X-100 – NaOH – ethanol has been proposed. The optimal conditions for the formation of micellarsaturated phases of the system under study have been established: 3.10-4 M 4-NA – 3.10-4 M NO2- – 5% Triton X-100 – 2.8 M NaOH – 10 vol. % С 2Н5ОН. A spectrophotometric study of the above system has been carried out. A linear dependence was built in the coordinates A (at λ max = 552 nm) vs с(thymol), which is described by an equation of the form A = f(c), A = 26291c + 0.02; R2 = 0.997. The range of the determined contents of thymol is (2·10-6 – 4·10-5) mol/l. A technique for the colorimetric determination of thymol in aqueous media (color channel G) has been developed. The intensity of the channel G chromaticity (IG) is linearly dependent on pc(thymol) in accordance with the equation IG = 54.2pc – 267, R 2 = 0; the lower limit of the determined contents of thymol is 1.10-6 mol/l, which is two times less than in the variant of its spectrophotometric determination. The profiles of petal diagrams in the color coordinates of the RGB CMYK model have been constructed; the dependences of their area (S) and perimeter (P) on the thymol concentration have been obtained (P: y = 278x – 10.13; R 2 = 0.97; S: y = 20182x – 87649, R 2 = 0.99).
Anton A. Denisov, Saratov State University, , Irina V. Shilova, Luydmila V. Grebenuyk,
Izvestiya of Saratov University. New Series. Series: Chemistry. Biology. Ecology, Volume 21; https://doi.org/10.18500/1816-9775-2021-21-3-335-341

Abstract:
Preliminary results of studies on the reintroduction of Calophaca wolgarica to the territory of the Saratov region are presented. In the period from 2018 to 2020, the age structure of artificial plantings and changes in the morphological parameters of individuals within them were studied. It is shown that on the territory of the Saratov region, artificial plantings of this species are best located near the protected area “Tulip Steppe near the village of Maksyutovo”. They marked the transition of plants from one ontogenetic state to another, the first generative plants appeared, which gave fruit. The habitat conditions of artificial plantings near the protected area “Ivanovo Field Tract” can be assessed as satisfactory – plant growth is slower, and the number of individuals that have passed from one age state to another is insignificant. Individuals of artificial plantings of C. wolgarica on one of the terraces of the Stepan Razin cliff mostly died, the remaining ones show general stagnation and extremely insignificant growth without transition to later age states.
Elena Yu. Rodionova, Kuban State University, , , Alexey A. Miroliubov
Izvestiya of Saratov University. New Series. Series: Chemistry. Biology. Ecology, Volume 21; https://doi.org/10.18500/1816-9775-2021-21-3-309-316

Abstract:
The study of acoustic signals from various representatives of insects, and in particular coleopterans, has a long history. In the Russian-language literature, systematic, faunistic and ecological studies on aquatic beetles, including those on the family Hydrophilidae, are widely known; however, studies on the bioacoustics of the coleopteran group are quite rare. The aim of our study was to study stress signals of two species of Hydrophilidae – Berosus frontifoveatus Kuwert, 1888 and Berosus spinosus Steven, 1808. The sounds of adults were recorded using a Behringer ECM8000 measuring condenser microphone. The sounds of B. spinosus males have a maximum frequency of occurrence in the range of 3729.31–4013.75 Hz, sounds of B. frontifoveatus is 4895.42–5842.76 Hz. The sounds of B. spinosus females have a maximum frequency of occurrence between 2585.98 and 2807.82 Hz. The sounds of B. frontifoveatus females have a maximum performance of the dominant frequency in the range of 2745.21–3476.23 Hz.
, Saratov State University
Izvestiya of Saratov University. New Series. Series: Chemistry. Biology. Ecology, Volume 21; https://doi.org/10.18500/1816-9775-2021-21-3-353-363

Abstract:
The Biological Faculty of the Saratov State University turns 90 years old in 2021. The first students were enrolled at the Faculty in the 1931–1932 academic year. However, the faculty’s history began long before its opening, when the Department of Botany and the Department of Zoology with Comparative Anatomy were organized in the new Saratov Imperial Nikolaev University in 1909. The article describes important events in the life of the Faculty and the contribution of scientists who stood at the origins of the birth of biological science at Saratov State University and played an important role in the formation and development of the Biological Faculty. A whole galaxy of famous biologists and eminent personalities worked at the university at different times. These are the academicians N. I. Vavilov, N. A. Maksimov, A. A. Richter, corresponding members A. Ya. Gordyagin, S. D. Lvov, professors D. E. Yanishevsky, A. D. Fursaev, I. V. Krasovskaya, V. S. Elpatevskiy, B. K. Fenyuk, P. A. Vunder, A. A. Chiguryaeva, S. S. Khokhlov, M. P. Gnutenko, V. V. Ignatov and others. They founded scientific schools, laid down faculty traditions and set a high standard for biological education, which the modern faculty team strives to maintain to this day.
, Perm State University
Izvestiya of Saratov University. New Series. Series: Philosophy. Psychology. Pedagogy, Volume 21; https://doi.org/10.18500/1819-7671-2021-21-3-268-272

Abstract:
The crisis state of society, expressed in the breakdown of traditional institutions, escalation of conflicts in the international arena, environmental problems, alienation and other issues need to be resolved. It is necessary to solve social problems by the whole society, but a problem arises here: while there is no unifying, universal platform and single identity, the society remains atomized and fragmented. Nevertheless, there have been attempts to create such a platform, with the formation of a common identity. The most striking example was the alter-globalization movement, which rebelled against the neoliberal version of globalization and all the problems it poses. In the opinion of the authors of this article, the alter-globalization movement fought for a truly general humanistic content of a process that would unite all mankind. It was this movement, despite the fact that it eventually collapsed, that set the vector of development for social movements for several decades to come. So, “Occupy Wall Street”, “square movements”, modern populist movements, etc. – all of them, despite many differences between them, one way or another, fought for another future, for an alternative, inalienable world. At the same time, in recent years, we can see that the tendency to unite people in the struggle for such a goal is only gaining momentum, which, apparently, will determine the socio-political agenda of our time for a long time to come. The novelty of this study is a view on socio-political movements as mechanisms for the development of a common human identity, where the “customer” is the whole modern crisis mankind.
, Ural State Pedagogical University
Izvestiya of Saratov University. New Series. Series: Philosophy. Psychology. Pedagogy, Volume 21; https://doi.org/10.18500/1819-7671-2021-21-3-334-338

Abstract:
The article is devoted to the description and analysis of pedagogical experience of professional competence formation in training and assessment of students in the point-rating system. The interdisciplinary nature of geographical education implies the need to develop special ways of thinking among students and to attract knowledge and skills from different subject areas. In such a situation, it is necessary to maximize the arrangement of the training process from the initial stage of learning to the stage of summative assessment. The work contains proposals to supplement the evaluation tools of expertise, knowledge and skills with innovative methods to better understand the success of students educational activities. A system of measures used by the teacher during the semester for formative and summative assessments to evaluate the level of competence development in students is described. Emphasis is placed on the possibility of using distance learning technologies in the point-rating system. A conclusion is made on the effectiveness of the score-rating assessment of the competence development level in geographical education and predictive capabilities of this method of control, particularly in Master's and postgraduate studies. The concept of the score-rating system proposed in the article was tested by the author while teaching a number of geographical subjects at Ural State Pedagogical University. This methodology has proven to be an effective method of increasing the organization and motivation of students.
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