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The paper considers issues of the Barents Sea shelf geodynamic evolution and influence of basement geologic structural processes on seabed morphology in their interaction. The obtained data have made possible to assume that the Norwegian-Mezenskaya rift system, Voronin graben, St. Anne and Victoria grabens were formed at the expense of the lithosphere stretching processes, but the Vostochno-Barentsevomorskaya basin and Medvezinsko-Edzinskaya area of depressions developed on the initial stage of lithosphere plate evolution due to collision of several island arcs and now all of them are outliers of the ancient oceanic crust. The technique of morphostructural analysis developed by the authors has allowed solve the inverse problem, and under morphological approach split all largest depressions on two main genetic types that confirm received geodynamic conclusion

Purpose. To carry out a kinematic analysis of a flat twelve-link hinged mechanism with three leading links, the basis of which is a structural group of links of the third class of the fourth order with rotational kinematic pairs, which is used in technological equipment. Methodology. The kinematic study of a flat complex mechanism of the third class with three leading links was performed using the mathematical modeling method in the Mathcad software environment. Findings. Using the method of mathematical modeling, the mechanism was presented in the form of free vectors built on its links, for which, taking into account the presence of three leading links, three vector contours were selected, which made it possible to draw up a system of vector equations of their closedness with further solving by a numerical method in the Mathcad software environment. The functions of the rotation angles of the mechanism links, their angular velocities and accelerations were obtained in analytical and graphical form depending on the rotation angle of the first driving crank of the mechanism, the calculation of the angular velocities and accelerations of all the driven links of the mechanism was performed. Originality. A sequence was developed and a kinematic study of a complex planar mechanism of the third class with three leading links was done, the basis of which is a structural group of links of the third class of the fourth order. Schematic modeling of the mechanism with three leading links was performed, a visualization schedule of its kinematic scheme was built, and a valid version of its assembly was obtained from many possible ones, for which the values of kinematic parameters of all its links were determined. Practical value. An analysis of the effect of the kinematic parameters of the three leading links of the third-class mechanism on the movement of the working body of the technological equipment was carried out. From the analysis of the obtained research results for the cycle of the mechanism the reason was found for the incomplete technological stoppage of the link, which should provide the working body of the machine for the required period of time. Recommendations of the elimination were made to identify the deficiency and proposals for the need to improve the drive of this equipment. [ABSTRACT FROM AUTHOR]

Purpose. Geometric synthesis of a statically determined spatial eight-link hinged mechanism with rotary kinematic pairs of a barreling machine, in which the working capacity carries out a complex spatial movement, followed by an analytical study of the structural features of the machine mechanism. Methodology. An analytical approach was used in the study of the eight-link hinged mechanism with rotary kinematic pairs, which consists of geometric and structural synthesis, and the design of barreling machine was modeled in the SolidWorks 2021 automated design software. Findings. One of the possible options for freeing the spatial mechanism of the barreling machine from passive connection is proposed, the synthesis of a statically determined spatial eight-link hinged mechanism with rotational kinematics is carried out. An appropriate design of a barreling machine with two driving links has been developed, the use of which creates conditions for increasing its reliability during operation and simultaneously increasing the productivity of performing the corresponding barreling operations. Analytical studies of the main geometric and structural parameters of the barreling machine were carried out. Originality. The connection between the corresponding geometric parameters of the synthesized statically determined spatial eight-link mechanism is established, which allows determining the rational ratio of the lengths of its links to each other. The relationship between the lengths of the links, their position and the angle of swing of the rocker arm together with the drive shaft of the machine is also established. Practical value. The synthesis of a statically determined spatial eight-link hinged mechanism with rotary kinematic pairs with two degrees of mobility was performed. Based on the synthesis of the mechanism, a new design of the barreling machine with two driving links was developed. Mathematical expressions for calculating the main geometric relationships of the link lengths of the developed machine structure were obtained. [ABSTRACT FROM AUTHOR]

In this paper, the concentration functions of electrical conductivity and pH are determined for aqueous solutions of an ionic liquid based on diethanolamine and boric acid (DEAB). Correlations between the physicochemical properties of an aqueous solution of DEAB and the processes of dissociation of the system components were established. Charge carriers in DEAB solutions are shown to be anions. It was established that an aqueous solution of DEAB has unipolar electrical conductivity and anion-exchange properties with an anion transfer number of 0.79. [ABSTRACT FROM AUTHOR]

The study of complex structural groups of links of flat mechanisms allows to improve the existing technological equipment and design new machines. Such mechanisms, based on structural groups of the fourth and higher classes, can ensure the implementation of innovative technological processes of production. Kinematic studies of complex flat mechanisms of the fourth class and higher are certainly relevant, if we take into account the individual approach to their research. The use of such mechanisms is increasingly observed in modern equipment that ensures the execution of technological processes at enterprises of the fashion industry. The work developed a sequence of actions for finding the velocity vectors of the points of the fourth-class mechanism with a moving closed loop, which is formed by four links, three of which have the form of complex links, is developed. The linear vectors of the velocities of the points coinciding with the geometric centers of the kinematic pairs of the structural group of links of the fourth class of the third order were determined. We conditionally changed the input mechanism to another structurally possible in a flat mechanism. The research was carried out using the graph-analytical method. In order to carry out a kinematic analysis of the mechanism, it is proposed to take into account the presence of complex links in its structure, namely the structural feature of the formation of a sequential connection of three links in a kinematic chain of the type “rocker arm – connecting rod – rocker arm”. This made it possible to determine the position of the instantaneous center of velocity of the link, which has plane-parallel motion. Conditional rotation of another conditionally leading link around such an instantaneous center of rotation made it possible to simplify the graphic constructions of the study. The application of the graph-analytical method made it possible to perform vector graphic constructions in an arbitrarily chosen scale for the entire mechanism, and after their completion, to perform detailed calculations of the scale of a certain vector construction. [ABSTRACT FROM AUTHOR]

The calibration process for flow conductometric sensors of electrical conductivity and their concentration in solutions of NaOH, NaCl, and Na2CO3 are studied. Two-electrode sensors in glass tubes were used with platinum electrodes combined with the developed resistometer. The measuring system resistometer-sensor KSN-19, KSN-22, and KSN-23 operates on a pulsed alternating current at a frequency of 4 kHz. The calibration dependences of the concentration-resistance sensors in the above solutions were measured. Three main parameters of the sensors were determined by means of special software processing of the calibration data and their comparison with precise reference functions, namely, the "sensor constant" KS, KS1, and KS3. It is shown that all characteristic parameters of the sensors depend on the chemical composition of the analyzed medium, and they are not constants. Theoretical substantiations of the observed regularity are given. [ABSTRACT FROM AUTHOR]

A sequence of actions is developed and a kinematic analysis of a complex planar mechanism of the fourth class with a structural group of links of the second order is carried out using mathematical models implemented in MathCad. The kinematic analysis is performed by the graphoanalytical method for validation purposes. The provisions of the theory of mechanisms and machines on the structural design of mechanisms are taken into account. The Assur singular point of a structural group of links of a complex mechanism is used. It is confirmed that the kinematic analysis is performed correctly with an accuracy of at least 95%, which is typical for engineering analyses. The proposed sequence of kinematic analysis of a complex planar mechanism can be used for similar studies of mechanisms of the fourth and higher classes. [ABSTRACT FROM AUTHOR]

New redundant-free seven-link hinge mechanisms of a machine with complex motion of the working tank have been developed. This machine is used for 3D machining of parts and mixing of bulk solids. The mathematical expressions for the analysis of the basic structural and geometrical parameters of the mechanisms are obtained. The configuration of the machine drive that allows the rotation of the driving shaft of the machine with simultaneous reciprocating motion is designed. The mathematical relations for the analysis of the basic structural parameters of the drive for keeping the pressure angle in the kinematic pair of the hinge mechanism within permissible limits are obtained. [ABSTRACT FROM AUTHOR]

To create reliable and highly efficient, energy- saving machines for light industry, it is necessary to study the dynamic processes of movement of the links of the mechanisms of which they are composed. Especially such studies should be given attention for machines, the mechanisms of which have a cyclic nature of action. During the execution of a technological operation in light industry machines with a periodic cyclic movement of the working bodies, an uneven movement of the main shaft occurs. This is caused by the movement of the links of the mechanism with certain accelerations and taking into account the periodic nature of the action of technological loads, which vary in magnitude and direction. The uneven nature of the movement leads to the appearance of additional loads in the kinematic pairs of mechanisms, mechanical vibrations in the mechanical transmission systems of motion, leads to the appearance of vibrations and violations in the positioning of the working bodies, affects the technological process of the equipment. Uniform and stable tension of the threads is the key to a high-quality performance of the loop formation process in knitwear. Additional dynamic loads affect the technological tension of textile threads during equipment operation. These loads are caused by the accelerated movement of the links of the mechanism, which is especially important for technological equipment with the presence of a reverse working stroke of its links. In such mechanisms, the values of the angular acceleration of the links and the linear acceleration of their individual points can acquire critically permissible values. It is possible to ensure the movement of the working bodies of the machine according to the law for which the tension of the threads will be optimally necessary. To do this, you need to choose the right type of mechanism that sets them in motion. The aim of the work is to conduct a structural-kinematic research of the mechanism of the reversible movement of the needle drum of a knitting machine, which will justify the selection of the required type of mechanism for such equipment. The confirmation of the improvement of the conditions for the formation of loops when knitting on a knitting machine with a reversible needle drum movement, made on the basis of a rocker mechanism, has been obtained. [ABSTRACT FROM AUTHOR]

The technological equipment of light industry has always used and will use complex multi-tier flat mechanisms of the upper classes. It is connected with the complexity of the trajectories and laws of motion of the workers of the loop-forming organs of technological equipment. This would not have been possible without the flat structural groups of links exceeding the second class in the well-known theory of the structure of mechanisms according to Assur. The use of the latest technologies in production require from manufacturers of technological equipment such machines that use mechanisms with structural groups of links of the third, fourth and higher classes. Research methods of structural groups that are formed by four links and six kinematic pairs, forming structural units of the third class of the third order or the fourth class of the second order are quite well known today. A different situation is observed with structural groups formed by six links and nine kinematic pairs. Such structural groups of links are used subject to insufficient analysis. There are no generally accepted methods for studying such groups of links due to the complexity of their implementation. The aim of the work is to conduct a structural analysis of the mechanism with a structural group of links of the third class of the fourth order using the method in which the initial mechanism conditionally changes. This leads to the determination of such a sequence of research, for which a decrease in the class of the mechanism is observed with a simultaneous simplification of its further analysis. When conducting this study takes into account the presence of three leading links of the mechanism. [ABSTRACT FROM AUTHOR]

The use of complex plane mechanisms in processing equipment of consumer industry is increasing. Improvement of existing processing equipment of consumer industry and design of new machines is connected with efficiency of existing analysis methods applied for structural link groups of plane mechanisms, of which the last are composed. The methods of research of dyads are the most effective today. Well known are the methods of analysis of structural groups consisting of four links. They form the 3rd class groups, on the basis of which the mechanisms of the relevant class can be structurally synthesized. On the one hand the fourth class structural groups are already being used or have significant prospects of application in processing equipment of consumer industry, on the other - the appropriateness (effectiveness) of their use is not theoretically justified because there is no known method for their kinematic and dynamic researches. Imperfection of analysis methods of such structural groups is a limiting factor of their use in processing equipment. The absence of a general method of kinematic research of these mechanisms allows us to accentuate the relevance of work on kinematic analysis of multilink mechanisms. Purpose of the work is to develop sequence of actions for kinematic research of accelerations of link points of a complex plane mechanism using the grapho-analytical method based on the provisions of the “Theoretical Mechanics” course on instantaneous acceleration center of links of the mechanism, which have plane-parallel motion. The acceleration vectors of link points of the second order fourth class group of complex plane mechanism are analyzed using grapho-analytical method, which provisionally modified initial mechanism has led to a class reduction of mechanism and allowed to conduct its research. [ABSTRACT FROM AUTHOR]