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A mechanism for blocking and subsequent annihilation of endogenous microcracks due to their intrastructural self-correction has been proposed. It has been established that during tribomechanical processes of friction interaction under conditions of additive influence of temperature fluctuations and specific loads in the contact zone, all possible factors take place simultaneously, from the point of view of physicochemical anomalous transformations in the solid phase, as a result of which thermal destruction of carbides and the formation of structurally free α-graphite. The test results prove that the anti-friction surface layer, which contains graphite, is formed in the run-in regime. The composition and the equilibrium roughness of the surface layer are reproduced and maintained throughout the normal range of wear, and also form an integral system of dynamically stable wear-resistant structures.

The Integrated Energy System (IES) of Ukraine functions as part of the European Union (EU) electric power system ENTSO-E. Each country whose IES operates in the ENTSO-E structure must ensure the presence of a full-fledged frequency and power automatic control system (AFPCS, AFPC system) in the national IES. The only exception is the IES of Ukraine, because its inclusion in the ENTSO-E happened during martial law and in the absence herewith of a fullfledged AFPC system. It violates the cornerstone requirements of the ENTSO-E structure formation. In the post-war period, the IES of Ukraine will be obliged to complete its own, full-fledged AFPCS as soon as possible. Three structures of the AFPC system development of the Ukrainian IES were studied: according to the traditional principle (on the basis of generators-regulators); on the basis of heat consumers-regulators with the involvement of heat pump installations and on the basis of heat consumers-regulators using electric heat generators that provide energy for the centralized heat supply system. Calculations and analysis of technical and economic indicators showed that the traditional structure of AFPCS extremely loses to both structures built on consumers-regulators. Significantly better of these two systems is the AFPCS, built on consumers-regulators in the form of electric heat generators. It provides an annual net profit of more than 1.8 billion USD, with a payback period of about 0.5 years, reduces by 2.7 billion m3 of natural gas consumption, reduces by 13.9 billion USD needs capital investment, has short construction deadlines. References 20, tables 5. [ABSTRACT FROM AUTHOR]

Subthreshold oscillations in combination with large-amplitude oscillations generate mixed-mode oscillations (MMOs), which mediate various spatial and temporal cognition and memory processes and behavioral motor tasks. Although many studies have shown that canard theory is a reliable method to investigate the properties underlying the MMOs phenomena, the relationship between the results obtained by applying canard theory and conductance-based models of neurons and their electrophysiological mechanisms are still not well understood. The goal of this study was to apply canard theory to the conductance-based model of pyramidal neurons in layer V of the Entorhinal Cortex to investigate the properties of MMOs under antiepileptic drug conditions (i.e., when persistent sodium current is inhibited). We investigated not only the mathematical properties of MMOs in these neurons, but also the electrophysiological mechanisms that shape spike clustering. Our results show that pyramidal neurons can display two types of MMOs and the magnitude of the slow potassium current determines whether MMOs of type I or type II would emerge. Our results also indicate that slow potassium currents with large time constant have significant impact on generating the MMOs, as opposed to fast inward currents. Our results provide complete characterization of the subthreshold activities in MMOs in pyramidal neurons and provide explanation to experimental studies that showed MMOs of type I or type II in pyramidal neurons under antiepileptic drug conditions.

Antifriction self-lubricating glass composite coatings of the Sic-Ni-Cu-Al-Si-C type additionally contain an aluminoborosilicate glass phase and structurally free MgC2, which forms α-graphite during thermolysis, the synergistic effect of which causes modification of the friction surface due to the formation antifriction layer. The influence of the structural components of the coating on their contribution to the antifriction properties is considered. It was clarified that an increase in the adhesive strength of the coatings was achieved by preliminary application of a sublayer of vitreous sodium silicate. The developed coatings showed high performance properties, while the means of minimizing and stabilizing wear characteristics was the presence of a thin-film antifriction layer based on α-graphite, which shields unacceptable processes of molecular-adhesive interaction. [ABSTRACT FROM AUTHOR]

Small-aperture transducers based on the magnetostrictive effect for the emission and reception of signals in the ultrasonic range in solid materials have been developed. The article discusses their design features and specifications. Attention is paid to the features of the choice of materials, shapes, and geometrical dimensions of the excitation coil, damper, and magnet. Structural and electrical circuits of the developed transducers are given. Some design and technological solutions have been proposed that can increase the radiation power by 10 times, and resolution by 2-3 times, compared with existing analogs. The area of the radiating part of the sensor is from 0.07 to 0.2 mm2 . Such transducers can be used in various diagnostic systems to detect defects in power equipment, aircraft products, industrial equipment, etc. [ABSTRACT FROM AUTHOR]