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An analysis is performed of a reduction in the intensity of cosmic rays during the minimum of solar cycle 24 in April–May, 2019. It is assumed that the observed slow decline and recovery of the cosmic ray flux consisted of a series of small Forbush decreases.

The spectrum of cosmic ray variations for the range of rigidities most sensitive to ground-based neutron monitors is determined experimentally according to direct measurements by the AMS-02 magnetic spectrometer.

It is found experimentally that a mesoscopic droplet phase is formed in low-concentration aqueous solutions of various polar organic compounds, which are considered in the chemical literature as infinitely soluble in water. The content of dissolved organic molecules in droplets is much higher than in the ambient solution. The droplet size increases with temperature. Theory can explain the mesodroplet formation by the phase separation of a binary mixture affected by the dichotomous noise of twinkling hydrogen bonds between molecules of organic compound and water. The Snyder polarity index, which is used by chemists as a miscibility criterion for molecular compounds, depends in the model on the dipole moments of mixed molecules and the energy and number of hydrogen bonds. With this refinement, it can be used as an estimation criterion for the existence and intensity (i.e., the number of droplets per unit volume of organic aqueous solution) of mesodroplet separation.

A mesoscale droplet phase, which is spontaneously formed in aqueous solutions of some polar organic compounds, has been experimentally investigated by methods of dynamic light scattering and laser phase microscopy. It is shown that tetrahydrofuran and tert-butanol aqueous solutions demonstrate a strong peak of light scattering intensity in the range of molecular concentrations of about 0.02 to 0.08, which corresponds to inhomogeneities with a characteristic size of about 100 nm. These liquid droplets are enriched with molecules of dissolved substance. A similar light scattering peak for aqueous solutions of glycerol and ethylene glycol is less pronounced. A theoretical model of the phase separation of binary solutions with twinkling (i.e., existing for a finite time) intermolecular hydrogen bonds is developed. The model predicts the existence of an additional low-concentration light scattering peak near the spinodal of the solution free of hydrogen bonds. A characterization of solutions according to the numerical values of twinkling hydrogen bond parameters is outlined.

Blast-furnace smelting today is organized so as to produce low-silicon hot metal, with subsequent desulfurization. In that case, economical furnace operation is facilitated by the use of low-ash coke characterized by hot strength and low adhesion to the slag melt, as well as stable chemical composition, minimum softening temperature range, and increased melting point of the iron. The production of low-silicon hot metal with

Experimental, industrial, and computational data provide the basis for the hydrogas-dynamic theory of counterflow coke packing in blast furnaces and corresponding technology. The conversion from slag-irrigated model packing to counterflow coke packing in a blast furnace is considered. The types of residue and the motion of the material fluxes through the packing are classified. The operation of the coke packing in the blast furnace is determined in terms of the fluxes of metal, slag, residue, and gas filling the space between the coke particles.

A high-voltage nanosecond impulse generator was developed and tested in order to create electromagnetic impulses (EMIs) in a given area. Tests revealed the characteristics of the generator’s output impulse: the rise (at a level 0.1–0.9) is about 3.2 ns, the length is 27 ns at half-deflation, and the magnitude is 2 MV. The generator is used to test large-size equipment for tolerance to industrial EMIs.

Elements of a hydrodynamic theory of the coke packing in blast furnaces are developed, with practical applications. The static and dynamic characteristics of the slag and the coke packing are deter-mined. Regression analysis indicates the relative significance of the factors in establishing the irrigation intensity and density of coke in the packing and the hearth by slag. The formation of slag residue is also investigated in the presence external and internal sources of smelting slag and titanium (iron) slag. The optimal irrigation density of the coke packing by the slag is determined.

Physical analysis suggests an integral sintering characteristic Ksi, which may be used not only to assess batch preparation at a particular plant, since it includes the structural characteristics of the granules and the batch bed, but also for the analysis and optimization of sinter production.

The high-temperature properties of various iron ores (including washing ore) are investigated in relation to blast-furnace operation.

The factors that determine the energy efficiency of an induction electric motor are listed. A strategy for developing a lineup of energy-efficient induction electric motors (IEM) is developed. Criteria for optimizing an electromagnetic core in an energy-efficient IEM are formulated. Actual results of the development of the first Russian lineup of energy-efficient IEMs are given.

A technique of using design calculations that minimize the number of varied parameters, to drastically decrease the variation range, to protect the optimization algorithm from entering an inadmissible region, and to speedup the calculation process is described. The mathematical model proposed can be used both within optimization software and independently. Experience gained from the stand-alone use of design-calculation software when developing a lineup of energy-efficient IEMs shows that the time of searching for an optimal version is reduced by a factor of two to three compared to the calculations performed using classical confirmatory analysis technique.

The basic results of the development of basic parts of a new lineup of asynchronous electric drives designed for operation within a variable-frequency electric drive are given. Their key differences from general-purpose commercial electric motors are shown.

209 The manufacture of housing components for nuclear reactors and chemical equipment calls for a large diameter seamless base, produced from mono lithic plates (5500 × 5500 mm or more; thickness 300– 400 mm). Such plates are made by opening out tubular forgings (external diameter 2400–2700 mm; length 5700–7000 mm) in several passes, using a flat tool, on a 150 MN hydraulic sheet stamping press (distance between the columns 10000 mm) [1, 2].

It is experimentally found that clusters containing 24 W or Mo atoms act as initial nuclei in CrO2 crystallization. Joint application of W or Mo compounds with Sb(III) compounds makes it possible to change the size of CrO2 particles in a very wide range. Thin (10–13 nm) CrO2 particles have a coercivity of about 450 Oe and are not superparamagnetic.

This manufacturing process is characterized by a long production cycle, inefficient use of the metal, considerable expenditure of effort, an unstable technology, and consequently poor quality of the welded blank obtained. This may be explained in that the thick sheet is rolled from the ingot without removing the most defective metal in the axial zone. In addition, existing electroslag-welding technology cannot ensure the required quality of the weld-seam and surrounding area, without plastic deformation of these zones. Thus, of ten 5500 × 5500 × 280 mm welded plates supplied to OAO Atommash, only two were regarded as suitable for the manufacture of the reactor-housing floor [5]. Investigation of the metal quality in the seam and the surrounding area shows the presence of the following defects: hot cracks in the central zone of the weld seam; an elongated (0.3‐0.8 m) gap in the basic metal in the near-seam zone; and longitudinal cracks in the near-seam zone, oriented at 45 ° ± 5 ° to the longitudinal axis of the seam. In addition, the formation of overlaid weld seams in welding the floor to the rest of the housing significantly reduces the reliability of housing operation.

A production technology is outlined for large one-piece plates that may be used to produce seamless large-diameter bases in nuclear-plant housings.