161 research outputs found
Analysis of technogenic impact (gas-industrial complex) on the state of soil and groundwater
The results of experimental studies of soil properties in area that was contaminated following the disaster at drilling of the gas-bearing-well at oil and gas production facility are represented. The local population uses this soil for agricultural purposes. Conclusions on the impact of emergency on the state of soil, natural and drinking water of decentralized water supply to nearby settlements are made
BARRIERS IN MUTUAL TRADE IN ELECTRIC ENERGY IN THE FRAMEWORK OF THE COMMON ELECTRIC POWER MARKET OF THE EURASIAN ECONOMIC UNION
The mutual trade in electricity between the Russian Federation and other members of the Eurasian Economic Union is considered. The existing barriers to the formation of the common electric power market of the Eurasian Economic Union have analysed. The possible variants of centralized electricity trading under fixedterm contracts and day ahead market have considered. Both positive and negative effects for the domestic electricity market have identified as the result of the formation of the common electric power market of the Eurasian Economic Union
THE ECONOMIC REASONS FOR THE DEVELOPMENT OF SOLAR GENERATION USING STANDALONE HYBRID POWER PLANTS IN ISOLATED ENERGY SYSTEMS
This article examines the significance of isolated energy systems for the Russian Federation. The dependence on expensive imported fuel in isolated energy systems and the need to develop alternative energy programs and energy efficiency of isolated systems have highlighted. The existing renewable energy sources in the territory of isolated energy systems have analysed and plans for their development have considered. In particular, an example of the implementation of energy-efficient autonomous hybrid power plants has presented by modernizing existing diesel power plants with the installation of solar panels
Functional testing of the lower extremity muscles
The purpose of the study was to increase the efficiency of diagnostics of the strength indicators of the lower extremity muscles by determining the optimal conditions for the mutual location of segments of kinematic links for the best implementation of contractile capabilities during functional testing. The main focus of the work was to determine the positions for the maximum overlaying of myofilaments in the sarcomeres of the investigated contractile areas of the movable segments of the lower extremities during power loads. 20 experienced football players, whose average age was 26.8Β±6.2 years, took part in the study. In order to fulfill the set goal, interference electromyography was performed on all athletes. The function of a separate group of muscles was considered in accordance with the endogenous ability to overcome external resistance in a given direction. Dependence of contractile manifestations was coordinated in accordance with the approach or distance of areas of attachment of muscles. The positions of the muscles were regulated by the ventral and sagittal planes, as well as by the average amplitude of rotation. On the basis of the ratio of maximum, average amplitudes and frequency, data regarding the maximum overlaying of myofilaments in sarcomeres (maximum bioelectric activity), in accordance with the position angle of the movable segment of the lower extremity were obtained. It was established that for conducting functional testing, the location of the trunk and lower extremities in the same plane of movement and axis were the optimal positions for the diarticular muscles of the thigh and lower leg; for monoarticular extensors of the lower leg - a position at a right angle between the lower leg and thigh; for rotators of the lower leg and foot - location of these segments in a plane parallel to the sagittal one. On the basis of the obtained data, the optimal conditions for the mutual location of the segments of the kinematic links for the realization of the contractile capabilities of the muscles of the lower extremities have been determined, a protocol for functional testing of the muscles of the lower extremities has been developed, it is presented in graphic form with the possibility of entering data from both limbs, while test points of rotator muscles of the thigh and lower leg have been added
The device for monitoring the insulation breakdown zone of power cable lines in distribution networks with isolated neutral system during high-voltage diagnostic
The article considers an electrical device designed for diagnostic work in distribution networks of 6-10 kV, namely, the determination of damage zones in case of failure of insulating materials of cable lines during high-voltage diagnostics with a rectified voltage of negative polarity. The novelty of the developed device is its ability to connect directly to a high-voltage cable line without additional matching devices. The device is capable of detecting damage zones in lines up to 10 km remotely with an error of up to 0.2% of the cable length. The prefix allows you to fix any variants of damage to single-phase and three-phase cable lines with high transient resistance at the site of damage without the operation of βburningβ insulation, which significantly reduces the time of repair work at the controlled facility
ΠΠΎΠ²ΡΠ΅ ΠΏΠΎΠ»ΠΈΠΊΠ°ΡΠ±ΠΎΠ½Π°ΡΡΠΈΠ»ΠΎΠΊΡΠ°Π½Ρ Π½Π° ΠΎΡΠ½ΠΎΠ²Π΅ ΡΠΈΠ»ΠΎΠΊΡΠ°Π½-N-ΡΡΠ°Π»ΠΈΠΌΠΈΠ΄ΠΈΠ½ΠΎΠ²
Objectives. Polymeric carbonate siloxanes containing a siloxane-N-phthalimidine group in the chain frame are new synthetic comb-like macromolecule systems. This work aims to study the possibility of applying them in the form of film materials for heat-resistant, high-performance gas-permeable membranes.Methods. Comb-like polycarbonate siloxanes of the siloxane-containing polyether class were obtained using various polycondensation methods. i.e., by the polymer-analogous transformation of polycarbonate-allyl-N-phthalimidines, using their reaction in an alkyl hydride siloxane solution; polycondensation of N-(3-(pentamethyldisiloxane)-propyl)-3,3-bis-(4'-hydroxyphenyl)phthalimidine with diphenylolpropane bis-chloroformate in a solution using triethylamine as an acceptor of hydrochloric acid; interphase polycondensation of the above reagents in a dichloromethane aqueous alkali system. The structures of the obtained initial and polymeric compounds were confirmed by proton nuclear magnetic resonance spectroscopy and elemental analysis. All of the synthesized comb-like copolymers had good solubility in several available solvents and film formations.Results. The new comb-like polycarbonate siloxanes had high thermal stability. According to thermogravimetric analysis, the introduction of up to 20 wt % siloxane units makes it possible to increase the heat resistance of polycarbonate siloxanes by 25 Β°C. Concurrently, their glasstransition temperature reaches 160 Β°C. Copolymers of polycarbonate siloxanes in the form of films have a high tensile strength above 50 MPa and an elastic modulus of up to 2000 MPa. The permeability coefficients of gases through a copolymer of polycarbonate siloxanes in the form of a film for several gases surpass the permeability of industrial polycarbonate from diphenylolpropane and fluorine-containing siloxane polycarbonate.Conclusions. The results achieved indicate the possibility of creating new polymeric combshaped siloxane systems with a variable structure that can contribute to obtaining the properties desired from them. Combined with high selectivity gas separation, this makes it possible to use such comb-shaped polycarbonate siloxanes as film membrane materials with an increased operating temperature range.Π¦Π΅Π»ΠΈ. ΠΠΎΠ»ΠΈΠΌΠ΅ΡΠ½ΡΠ΅ ΠΊΠ°ΡΠ±ΠΎΠ½Π°ΡΡΠΈΠ»ΠΎΠΊΡΠ°Π½Ρ, ΡΠΎΠ΄Π΅ΡΠΆΠ°ΡΠΈΠ΅ Π² ΠΎΠ±ΡΠ°ΠΌΠ»Π΅Π½ΠΈΠΈ ΡΠ΅ΠΏΠΈ ΡΠΈΠ»ΠΎΠΊΡΠ°Π½-N-ΡΡΠ°Π»ΠΈΠΌΠΈΠ΄ΠΈΠ½ΠΎΠ²ΡΡ Π³ΡΡΠΏΠΏΠΈΡΠΎΠ²ΠΊΡ, ΡΠ²Π»ΡΡΡΡΡ Π½ΠΎΠ²ΡΠΌΠΈ ΡΠΈΠ½ΡΠ΅ΡΠΈΡΠ΅ΡΠΊΠΈΠΌΠΈ Π³ΡΠ΅Π±Π½Π΅ΠΎΠ±ΡΠ°Π·Π½ΡΠΌΠΈ ΡΠΈΡΡΠ΅ΠΌΠ°ΠΌΠΈ ΠΌΠ°ΠΊΡΠΎΠΌΠΎΠ»Π΅ΠΊΡΠ». Π¦Π΅Π»Ρ ΡΠ°Π±ΠΎΡΡ β ΠΈΠ·ΡΡΠΈΡΡ Π²ΠΎΠ·ΠΌΠΎΠΆΠ½ΠΎΡΡΡ ΠΈΡ
ΠΏΡΠΈΠΌΠ΅Π½Π΅Π½ΠΈΡ Π² Π²ΠΈΠ΄Π΅ ΠΏΠ»Π΅Π½ΠΎΡΠ½ΡΡ
ΠΌΠ°ΡΠ΅ΡΠΈΠ°Π»ΠΎΠ² Π΄Π»Ρ ΡΠ΅ΡΠΌΠΎΡΡΠΎΠΉΠΊΠΈΡ
Π²ΡΡΠΎΠΊΠΎΡΡΡΠ΅ΠΊΡΠΈΠ²Π½ΡΡ
Π³Π°Π·ΠΎΠΏΡΠΎΠ½ΠΈΡΠ°Π΅ΠΌΡΡ
ΠΌΠ΅ΠΌΠ±ΡΠ°Π½.ΠΠ΅ΡΠΎΠ΄Ρ. ΠΡΠ΅Π±Π½Π΅ΠΎΠ±ΡΠ°Π·Π½ΡΠ΅ ΠΏΠΎΠ»ΠΈΠΊΠ°ΡΠ±ΠΎΠ½Π°ΡΡΠΈΠ»ΠΎΠΊΡΠ°Π½Ρ ΠΊΠ»Π°ΡΡΠ° ΡΠΈΠ»ΠΎΠΊΡΠ°Π½-ΡΠΎΠ΄Π΅ΡΠΆΠ°ΡΠΈΡ
ΠΏΠΎΠ»ΠΈΡΡΠΈΡΠΎΠ² Π±ΡΠ»ΠΈ ΠΏΠΎΠ»ΡΡΠ΅Π½Ρ ΡΠ°Π·Π»ΠΈΡΠ½ΡΠΌΠΈ ΠΏΠΎΠ»ΠΈΠΊΠΎΠ½Π΄Π΅Π½ΡΠ°ΡΠΈΠΎΠ½Π½ΡΠΌΠΈ ΠΌΠ΅ΡΠΎΠ΄Π°ΠΌΠΈ: ΠΏΠΎΠ»ΠΈΠΌΠ΅ΡΠ°Π½Π°Π»ΠΎΠ³ΠΈΡΠ½ΡΠΌ ΠΏΡΠ΅Π²ΡΠ°ΡΠ΅Π½ΠΈΠ΅ΠΌ ΠΏΠΎΠ»ΠΈΠΊΠ°ΡΠ±ΠΎΠ½Π°Ρ-Π°Π»Π»ΠΈΠ»-N-ΡΡΠ°Π»ΠΈΠΌΠΈΠ΄ΠΈΠ½ΠΎΠ² ΠΈΡ
ΡΠ΅Π°ΠΊΡΠΈΠ΅ΠΉ Π² ΡΠ°ΡΡΠ²ΠΎΡΠ΅ Ρ Π°Π»ΠΊΠΈΠ»Π³ΠΈΠ΄ΡΠΈΠ΄ΡΠΈΠ»ΠΎΠΊΡΠ°Π½Π°ΠΌΠΈ; ΠΏΠΎΠ»ΠΈΠΊΠΎΠ½Π΄Π΅Π½ΡΠ°ΡΠΈΠ΅ΠΉ N-(3-(ΠΏΠ΅Π½ΡΠ°ΠΌΠ΅ΡΠΈΠ»Π΄ΠΈΡΠΈΠ»ΠΎΠΊΡΠΈ)-ΠΏΡΠΎΠΏΠΈΠ»)-3,3-Π±ΠΈΡ-(4'-ΠΎΠΊΡΠΈ-ΡΠ΅Π½ΠΈΠ»)ΡΡΠ°Π»ΠΈΠΌΠΈΠ΄ΠΈΠ½Π° Ρ Π±ΠΈΡ-Ρ
Π»ΠΎΡΡΠΎΡΠΌΠΈΠ°ΡΠΎΠΌ Π΄ΠΈΡΠ΅Π½ΠΈΠ»ΠΎΠ»ΠΏΡΠΎΠΏΠ°Π½Π° Π² ΡΠ°ΡΡΠ²ΠΎΡΠ΅, ΠΈΡΠΏΠΎΠ»ΡΠ·ΡΡ ΡΡΠΈΡΡΠΈΠ»Π°ΠΌΠΈΠ½ Π² ΠΊΠ°ΡΠ΅ΡΡΠ²Π΅ Π°ΠΊΡΠ΅ΠΏΡΠΎΡΠ° ΡΠΎΠ»ΡΠ½ΠΎΠΉ ΠΊΠΈΡΠ»ΠΎΡΡ ΠΈΠ»ΠΈ ΠΌΠ΅ΠΆΡΠ°Π·Π½ΠΎΠΉ ΠΏΠΎΠ»ΠΈΠΊΠΎΠ½Π΄Π΅Π½ΡΠ°ΡΠΈΠ΅ΠΉ ΡΠΊΠ°Π·Π°Π½Π½ΡΡ
ΡΠ΅Π°Π³Π΅Π½ΡΠΎΠ² Π² ΡΠΈΡΡΠ΅ΠΌΠ΅ ΠΌΠ΅ΡΠΈΠ»Π΅Π½Ρ
Π»ΠΎΡΠΈΠ΄βΠ²ΠΎΠ΄Π½Π°Ρ ΡΠ΅Π»ΠΎΡΡ. Π‘ΡΡΡΠΊΡΡΡΡ ΠΏΠΎΠ»ΡΡΠ΅Π½Π½ΡΡ
ΠΈΡΡ
ΠΎΠ΄Π½ΡΡ
ΠΈ ΠΏΠΎΠ»ΠΈΠΌΠ΅ΡΠ½ΡΡ
ΡΠΎΠ΅Π΄ΠΈΠ½Π΅Π½ΠΈΠΉ Π±ΡΠ»ΠΈ ΠΏΠΎΠ΄ΡΠ²Π΅ΡΠΆΠ΄Π΅Π½Ρ ΡΠΏΠ΅ΠΊΡΡΠΎΡΠΊΠΎΠΏΠΈΠ΅ΠΉ ΡΠ΄Π΅ΡΠ½ΠΎΠ³ΠΎ ΠΌΠ°Π³Π½ΠΈΡΠ½ΠΎΠ³ΠΎ ΡΠ΅Π·ΠΎΠ½Π°Π½ΡΠ° 1 H ΠΈ ΡΠ»Π΅ΠΌΠ΅Π½ΡΠ½ΡΠΌ Π°Π½Π°Π»ΠΈΠ·ΠΎΠΌ. Π‘Π²ΠΎΠΉΡΡΠ²ΠΎΠΌ Π²ΡΠ΅Ρ
ΡΠΈΠ½ΡΠ΅Π·ΠΈΡΠΎΠ²Π°Π½Π½ΡΡ
Π³ΡΠ΅Π±Π½Π΅ΠΎΠ±ΡΠ°Π·Π½ΡΡ
ΡΠΎΠΏΠΎΠ»ΠΈΠΌΠ΅ΡΠΎΠ² ΡΠ²Π»ΡΠ΅ΡΡΡ ΠΈΡ
Ρ
ΠΎΡΠΎΡΠ°Ρ ΡΠ°ΡΡΠ²ΠΎΡΠΈΠΌΠΎΡΡΡ Π² ΡΡΠ΄Π΅ Π΄ΠΎΡΡΡΠΏΠ½ΡΡ
ΡΠ°ΡΡΠ²ΠΎΡΠΈΡΠ΅Π»ΡΡ
ΠΈ ΠΏΠ»Π΅Π½ΠΊΠΎΠΎΠ±ΡΠ°Π·ΠΎΠ²Π°Π½ΠΈΠ΅.Π Π΅Π·ΡΠ»ΡΡΠ°ΡΡ. ΠΠΎΠΊΠ°Π·Π°Π½ΠΎ, ΡΡΠΎ Π½ΠΎΠ²ΡΠ΅ Π³ΡΠ΅Π±Π½Π΅ΠΎΠ±ΡΠ°Π·Π½ΡΠ΅ ΠΏΠΎΠ»ΠΈΠΊΠ°ΡΠ±ΠΎΠ½Π°ΡΡΠΈΠ»ΠΎΠΊΡΠ°Π½Ρ ΠΎΠ±Π»Π°Π΄Π°ΡΡ Π²ΡΡΠΎΠΊΠΎΠΉ ΡΠ΅ΡΠΌΠΈΡΠ΅ΡΠΊΠΎΠΉ ΡΡΡΠΎΠΉΡΠΈΠ²ΠΎΡΡΡΡ. ΠΠΎ Π΄Π°Π½Π½ΡΠΌ ΡΠ΅ΡΠΌΠΎΠ³ΡΠ°Π²ΠΈΠΌΠ΅ΡΡΠΈΡΠ΅ΡΠΊΠΎΠ³ΠΎ Π°Π½Π°Π»ΠΈΠ·Π° Π²Π²Π΅Π΄Π΅Π½ΠΈΠ΅ Π² ΡΠΎΠΏΠΎΠ»ΠΈΠΌΠ΅Ρ Π΄ΠΎ 20 ΠΌΠ°ΡΡ. % ΡΠΈΠ»ΠΎΠΊΡΠ°Π½ΠΎΠ²ΡΡ
Π·Π²Π΅Π½ΡΠ΅Π² ΠΏΠΎΠ·Π²ΠΎΠ»ΡΠ΅Ρ ΠΏΠΎΠ²ΡΡΠΈΡΡ ΡΠ΅ΡΠΌΠΎΡΡΠΎΠΉΠΊΠΎΡΡΡ ΠΏΠΎΠ»ΠΈΠΊΠ°ΡΠ±ΠΎΠ½Π°ΡΡΠΈΠ»ΠΎΠΊΡΠ°Π½ΠΎΠ² Π½Π° 25 Β°C. ΠΡΠΈ ΡΡΠΎΠΌ, ΡΠ΅ΠΌΠΏΠ΅ΡΠ°ΡΡΡΠ° ΡΡΠ΅ΠΊΠ»ΠΎΠ²Π°Π½ΠΈΡ ΠΈΡ
Π΄ΠΎΡΡΠΈΠ³Π°Π΅Ρ 160 Β°C. Π‘ΠΎΠΏΠΎΠ»ΠΈΠΌΠ΅ΡΡ ΠΏΠΎΠ»ΠΈΠΊΠ°ΡΠ±ΠΎΠ½Π°ΡΡΠΈΠ»ΠΎΠΊΡΠ°Π½ΠΎΠ² Π² Π²ΠΈΠ΄Π΅ ΠΏΠ»Π΅Π½ΠΎΠΊ ΠΎΠ±Π»Π°Π΄Π°ΡΡ Π²ΡΡΠΎΠΊΠΎΠΉ ΠΏΡΠΎΡΠ½ΠΎΡΡΡΡ Π½Π° ΡΠ°Π·ΡΡΠ² Π²ΡΡΠ΅ 50 ΠΠΠ° ΠΈ ΠΌΠΎΠ΄ΡΠ»Π΅ΠΌ ΡΠΏΡΡΠ³ΠΎΡΡΠΈ Π΄ΠΎ 2000 ΠΠΠ°. ΠΠΎΡΡΡΠΈΡΠΈΠ΅Π½ΡΡ ΠΏΡΠΎΠ½ΠΈΡΠ°Π΅ΠΌΠΎΡΡΠΈ Π³Π°Π·ΠΎΠ² ΡΠ΅ΡΠ΅Π· coΠΏΠΎΠ»ΠΈΠΌΠ΅Ρ ΠΏΠΎΠ»ΠΈΠΊΠ°ΡΠ±ΠΎΠ½Π°ΡΡΠΈΠ»ΠΎΠΊΡΠ°Π½ΠΎΠ² Π² Π²ΠΈΠ΄Π΅ ΠΏΠ»Π΅Π½ΠΊΠΈ ΠΏΠΎ ΡΡΠ΄Ρ Π³Π°Π·ΠΎΠ² ΠΏΡΠ΅Π²ΠΎΡΡ
ΠΎΠ΄ΡΡ ΠΏΡΠΎΠ½ΠΈΡΠ°Π΅ΠΌΠΎΡΡΡ Π΄Π»Ρ ΠΏΡΠΎΠΌΡΡΠ»Π΅Π½Π½ΠΎΠ³ΠΎ ΠΏΠΎΠ»ΠΈΠΊΠ°ΡΠ±ΠΎΠ½Π°ΡΠ° ΠΈΠ· Π΄ΠΈΡΠ΅Π½ΠΈΠ»ΠΎΠ»ΠΏΡΠΎΠΏΠ°Π½Π° ΠΈ ΡΡΠΎΡΡΠΎΠ΄Π΅ΡΠΆΠ°ΡΠ΅Π³ΠΎ ΡΠΈΠ»ΠΎΠΊΡΠ°Π½ΠΎΠ²ΠΎΠ³ΠΎ ΠΏΠΎΠ»ΠΈΠΊΠ°ΡΠ±ΠΎΠ½Π°ΡΠ°.ΠΡΠ²ΠΎΠ΄Ρ. ΠΠΎΡΡΠΈΠ³Π½ΡΡΡΠ΅ ΡΠ΅Π·ΡΠ»ΡΡΠ°ΡΡ ΡΠ²ΠΈΠ΄Π΅ΡΠ΅Π»ΡΡΡΠ²ΡΡΡ ΠΎ Π²ΠΎΠ·ΠΌΠΎΠΆΠ½ΠΎΡΡΠΈ ΡΠΎΠ·Π΄Π°Π½ΠΈΡ Π½ΠΎΠ²ΡΡ
ΠΏΠΎΠ»ΠΈΠΌΠ΅ΡΠ½ΡΡ
Π³ΡΠ΅Π±Π½Π΅ΠΎΠ±ΡΠ°Π·Π½ΡΡ
ΡΠΈΠ»ΠΎΠΊΡΠ°Π½ΠΎΠ²ΡΡ
ΡΠΈΡΡΠ΅ΠΌ Ρ Π²Π°ΡΡΠΈΡΡΠ΅ΠΌΠΎΠΉ ΡΡΡΡΠΊΡΡΡΠΎΠΉ, ΠΊΠΎΡΠΎΡΠ°Ρ ΡΠΏΠΎΡΠΎΠ±ΡΡΠ²ΡΠ΅Ρ Π΄Π»Ρ Π½ΠΈΡ
ΠΏΠΎΠ»ΡΡΠ΅Π½ΠΈΡ Π·Π°Π΄Π°Π½Π½ΡΡ
ΡΠ²ΠΎΠΉΡΡΠ². Π ΡΠΎΡΠ΅ΡΠ°Π½ΠΈΠΈ Ρ Π²ΡΡΠΎΠΊΠΎΠΉ ΡΠ΅Π»Π΅ΠΊΡΠΈΠ²Π½ΠΎΡΡΡΡ ΡΠ°Π·Π΄Π΅Π»Π΅Π½ΠΈΡ Π³Π°Π·ΠΎΠ² ΡΡΠΎ ΠΏΠΎΠ·Π²ΠΎΠ»ΡΠ΅Ρ ΠΈΡΠΏΠΎΠ»ΡΠ·ΠΎΠ²Π°ΡΡ Π½ΠΎΠ²ΡΠ΅ Π³ΡΠ΅Π±Π½Π΅ΠΎΠ±ΡΠ°Π·Π½ΡΠ΅ ΠΏΠΎΠ»ΠΈΠΊΠ°ΡΠ±ΠΎΠ½Π°ΡΡΠΈΠ»ΠΎΠΊΡΠ°Π½Ρ Π² ΠΊΠ°ΡΠ΅ΡΡΠ²Π΅ ΠΏΠ»Π΅Π½ΠΎΡΠ½ΡΡ
ΠΌΠ΅ΠΌΠ±ΡΠ°Π½Π½ΡΡ
ΠΌΠ°ΡΠ΅ΡΠΈΠ°Π»ΠΎΠ² Ρ ΠΏΠΎΠ²ΡΡΠ΅Π½Π½ΡΠΌ ΠΈΠ½ΡΠ΅ΡΠ²Π°Π»ΠΎΠΌ ΡΠ°Π±ΠΎΡΠΈΡ
ΡΠ΅ΠΌΠΏΠ΅ΡΠ°ΡΡΡ
Magnetorheological effect of magnetoactive elastomer with a permalloy filler
Within the frames of this study, the synthesis of a permalloy to be used as a filler for magnetoactive and magnetorheological elastomers (MAEs and MREs) was carried out. By means of the mechanochemical method, an alloy with the composition 75 wt.% of Fe and 25 wt.% of Ni was obtained. The powder of the product was utilized in the synthesis of MAEs. Study of the magnetorheological (MR) properties of the elastomer showed that in a ~400 mT magnetic field the shear modulus of the MAE increased by a factor of ~200, exhibiting an absolute value of ~8 MPa. Furthermore, we obtained experimentally a relative high loss factor for the studied composite; this relates to the size and morphology of the synthesized powder. The composite with such properties is a very perspective material for magnetocontrollable damping devices. Under the action of an external magnetic field, chain-like structures are formed inside the elastomeric matrix, which is the main determining factor for obtaining a high MR effect. The effect of chain-like structures formation is most pronounced in the region of small strains, since structures are partially destroyed at large strains. A proposed theoretical model based on chain formation sufficiently well describes the experimentally observed MR effect. The peculiarity of the model is that chains of aggregates of particles, instead of individual particles, are considered. Β© 2020 by the authors. Licensee MDPI, Basel, Switzerland.This work is supported by the research association between the Deutsche Forschungsgemeinschaft (DFG) under Grant Bo 3343/2β1 within PAK 907 and support of RFBR under Grant 19β53β12039. A.M., A.Z. are grateful the RFBR, projects 19β31β90003, 19β52β45001, 20β02β00022 and the Ministry of Science and Higher Education of the Russian Federation, project β FEUZβ2020β0051
Functional testing of the lower extremity muscles
The purpose of the study was to increase the efficiency of diagnostics of the strength indicators of the lower extremity muscles by determining the optimal conditions for the mutual location of segments of kinematic links for the best implementation of contractile capabilities during functional testing. The main focus of the work was to determine the positions for the maximum overlaying of myofilaments in the sarcomeres of the investigated contractile areas of the movable segments of the lower extremities during power loads. 20 experienced football players, whose average age was 26.8Β±6.2 years, took part in the study. In order to fulfill the set goal, interference electromyography was performed on all athletes. The function of a separate group of muscles was considered in accordance with the endogenous ability to overcome external resistance in a given direction. Dependence of contractile manifestations was coordinated in accordance with the approach or distance of areas of attachment of muscles. The positions of the muscles were regulated by the ventral and sagittal planes, as well as by the average amplitude of rotation. On the basis of the ratio of maximum, average amplitudes and frequency, data regarding the maximum overlaying of myofilaments in sarcomeres (maximum bioelectric activity), in accordance with the position angle of the movable segment of the lower extremity were obtained. It was established that for conducting functional testing, the location of the trunk and lower extremities in the same plane of movement and axis were the optimal positions for the diarticular muscles of the thigh and lower leg; for monoarticular extensors of the lower leg - a position at a right angle between the lower leg and thigh; for rotators of the lower leg and foot - location of these segments in a plane parallel to the sagittal one. On the basis of the obtained data, the optimal conditions for the mutual location of the segments of the kinematic links for the realization of the contractile capabilities of the muscles of the lower extremities have been determined, a protocol for functional testing of the muscles of the lower extremities has been developed, it is presented in graphic form with the possibility of entering data from both limbs, while test points of rotator muscles of the thigh and lower leg have been added
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