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Introduction of measures for intra-day of regulating runoff incoming water flow rates from the Nizhny Novgorod HPP and their discharge through the spillway of the Nizhny Novgorod low-pressure hydroelectric complex requires a specific algorithm for dispatcher actions of the created hydraulic system. At the same time, there are serious difficulties in predicting the water regime over time. As previous studies have shown there is a large unevenness and irregularity of water discharges not only during the same day, but also in the same periods of each day, as well as weeks, months, and years. Тhis article analyzes the boundary conditions when introducing measures of regulating runoff, a mathematical model and an algorithm for solving the problem of intraday regulation are developed, describing the sequence of actions for solving the problem of "smoothing" the flow rates supplied to the lower stream of the Nizhny Novgorod low-pressure hydroelectric complex. The implementation of the proposed measures is carried out according to a three-stage (or two-stage) schedule for regulating the flow rate and water level. The proposed measures will improve the hydraulic and hydrological conditions of the downstream reach of the Nizhny Novgorod low-pressure hydroelectric complex by which the necessary depths for navigation will be reached. Conditions have also been created to mitigate erosion processes.

The article considers possible problems for shipping, which may arise after the construction and commissioning of the Nizhny Novgorod low-pressure hydroelectric complex. By analyzing the available data on the change in navigation expenses through the Nizhny Novgorod hydroelectric power station and the predicted calculation of the water regime in the alignment of the created Nizhny Novgorod low-pressure hydroelectric system, it is ascertained in the article whether the navigable dimensions in depth are ensured in the section above and below the alignment of the NNSU during the navigation period. In order to determine the possibility of regulating runoff on a spillway of the Nizhny Novgorod State University, an experiment is set up at the Volga State Unversity of Water Transport laboratory, during which the speed and time parameters of the water flow are established. The article presents the results of the work.

The main features of high-voltage electropulse consolidation (H-VEC) of powder materials and the unique possibilities of the method caused by them are considered. The electrothermal processes in the H-VEC at the contacts between the powder particles and in the macroscale of the whole consolidated sample are analyzed. The results of calculations of the dynamics of closure (collapse) of interparticle pores in the consolidated material are presented.

Welded circular seams of “choke joints”, as a rule, have deviations from the specified diameter. This leads to uneven deformation, and sometimes to the absence of deformations in some areas of the seam. With repeated static loads, destruction arises in these places. To connect to the maintenance system of connections with the base metal, used as a guide, surface plastic deformation of the zone zone is carried out. A technology and equipment have been developed that allow plastically deforming the area of transition from the weld to the base metal along the entire length of the circular weld. As a result of plastic deformation along the technological groove, the characteristics of low-cycle fatigue of welded joints are obtained, which are not inferior to the base metal. To reduce stresses in the zone of transition from the weld to the base metal, it is proposed, first, to perform a circular groove on the base metal by machining, as close as possible to the specified zone. To assess the influence of the shape and size of the groove on the stress-strain state of the zone of conjugation of the weld metal with the base metal, FEM calculations were carried out

This work shows the experimental results of the effect of Ar + O 2 background gas pressure under pulsed laser deposition on the formation of LiNbO3 films and their morphological properties. It was found that when the pressure of the Ar + O 2 mixture increased from 10-3 Torr to 10-2 Torr, the grain diameter of the films decreased from (196±7) nm to (137±5) nm, and the obtained films at the pressure of 100 consisted of separate clusters with diameter (59±4) nm. Based on the obtained results, an architecture of piezoelectric nanogenerator was developed and its parameters were investigated.

The construction of universal pulsed welding equipment for producing stamped-welded thin-wall structures is described. A dual action press was designed for preliminary static and pulsed loading in solid-phase welding of materials. In the process of pulsed-discharge welding, the weld zone is subjected to the thermal effect by passing current and applying pressure using an induction-dynamic drive. The main element of the drive is the induction coil. The energy source is a high-voltage generator of pulsed currents. A special measuring stand has been developed for applied studies and determination of the conditions of magnetic-pulsed welding forming of tubular components. The system can be used to fix the amplitude values and the frequency of discharge current and magnetic pressure and also the RLC parameters of the discharge circuit of the pulsed-current generator. The dual action press and the measuring stand are used in a section for producing lightweight stamped-welded screened casings of board ca...

Authors of article offer the mixed technology of receiving the facilitated screening casing from aluminum foil of 0,15÷0,2 mm thickness by the means of magnetic-pulse welding preforming (MPWP) combining thermal and force impact on processed material.The physical entity of MPWF is described, parameters of the modes of welding are specified, metallographic researches of a zone of welded connection are conducted.The press of double action realizing static and impulse loading on processed material is developed.

The report shows the classification of methods of high-voltage capacitor welding (HVCW) with magnetic drive pulse applied to the preparation of joints such as "rod - drive" of non-ferrous metals and alloys. Researches of processing methods of process of HVCW are provided. The ranges of energetic, geometrical parameters are defined and dependences of durability of welded connections are given. The hypothesis is offered and usage considerations on HVCW are made.

The problem of reducing the weight and screening on-board cable systems of space equipment against radio interference is solved. To solve the problem, a method of producing lightweight stamped-welded screening casings of connectors by magnetic–pulsed welding–forming (MPWF) has been developed. The results of theoretical analysis and experimental studies of the MPWF process are used to determine the mechanism of formation of welded joints, the energy parameters of the process and the geometrical parameters of assembling, influencing the quality of the welded joints and the degree of deformation in forming. The experimental results are used to design and manufacture a welding–forming installation with induction coils for MPWF of the lightweight screening casings.

The technologies of the physics of open systems are applied to generate the systemic knowledge about variations in gene activity under the impact of chemical stressors. The system knowledge is automatically generated based on the genomic data obtained by using the microarray technology. The system knowledge has been used for scientific understanding and rational explanation of regular changes in gene activity depending on the biomaterial sample, type of the chemical and its concentration, and time series of experiments.

The article discusses the possibility of using electromagnetic influence in the production of permanent compounds such as metal–ceramics, metal–glass, as well as composite compounds from powder materials. It is proposed to use magnetic pulse action to form such joints in the solid phase: in the atmosphere with the position of parts at an angle; in vacuum with preheating and subsequent radial action. When consolidating powder materials (sintering with simultaneous pressing), a scheme of synchronous action of electromagnetic energy is proposed: thermal and mechanical.

An experimental investigation is reported on the influence of UV or IR incoherent irradiation on nanolithography by tip-induced local anodic oxidation as applied to titanium films. Both forms of irradiation are found to increase the uniformity of feature sizes and to improve the resolution of the lithographic technique. It is also shown that UV irradiation makes it possible to produce a conducting channel 11 nm wide.