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The prospects of composite materials based on polymer matrices with the inclusion of carbon nanotubes, including oriented carbon nanotubes, as both functional and structural materials for nanosatellites are considered. The thermal conductivity and electrical conductivity of the composites has been measured. Techniques for producing carbon nanotubes, including vertically oriented nanotubes synthesized on filaments, and coaxial regular nanomesostructures as a functional additive for varying the properties of materials are proposed.

The Moscow University Universat-SOCRAT program is aimed at using small satellites to monitor space threats, such as radiation in near-earth space, electromagnetic transients, and potentially dangerous bodies of natural and artificial origins. The first stage of the program implementation began on July 5, 2019 as a result of the successful launch of three Cubesat-type nanosatellites from the Vostochny cosmodrome. These satellites are equipped with instruments for space radiation monitoring, as well as prototypes of devices for observing transient phenomena in the Earth’s atmosphere. In particular, two satellites are equipped with scintillation phosphich detectors that detect charged particles and gamma quanta in the energy release range of 0.1–2 MeV. The geometric factor of these instruments is $${\approx}50$$ cm $${}^{2}$$ sr. One of the Cubesats also carries an optical photometer, consisting of four silicon photomultipliers, which entrance windows are covered with different light filters. The satellites were launched into solar-synchronous orbits with an altitude of $${\approx}550$$ km. This makes favorable conditions for space radiation monitoring in various areas of near-Earth space, including zones of trapped radiation, areas of precipitation, etc. Such an orbit also allows observations of flare phenomena both in the equatorial atmosphere and at high latitudes. The first results of flight tests are discussed.

This paper considers an original valve electromagnet with integrated armature, designed to implement an electromagnetic overcurrent release of a circuit breaker. Theoretical and experimental studies of the proposed electromagnet have been carried out to determine the most important parameters of circuit breakers such as sensitivity and high-speed performance. Calculations and experiments have shown the possibility of increasing the sensitivity and speed of the electromagnetic overcurrent release based on the proposed electromagnet with integrated armature in comparison with existing structures used in modern circuit breakers.

Spectra obtained using a four-electrode measurement scheme in a medium with dispersion are modeled mathematically using the example of a three-dimensional cell culture. The problem is solved with the finite element approach by assuming there are no inductive phenomena in the studied system in a given range of frequencies. The electrical characteristics of the electrodes are considered.

A mathematical model is presented that describes the distribution of the potential and electric field strength in cells of a microfluidic device for culturing a cellular monolayer with built-in electrodes of different geometries. The design of the measuring cell and the geometry of the electrodes are selected by analyzing the results from calculations.

A method for the design calculation of an electromagnet minimized by the mass of active materials, according to the dynamics, is proposed. The results of calculating the dynamic parameters of the actuating element of the circuit breakers are given: the starting time, travel time, and response time. The calculations were performed taking into account the influence on the dynamic parameters of eddy currents in the secondary circuit of the valve electromagnet. The influence on the basic dynamic parameters of such initial design data as the initial value of the working air gap, the initial mechanical force, and ambient temperature is analyzed.

The parameters of coordination bonds M ← OH2 (the magnetic moments of transition metals, interatomic distances, force constants, and break energies) in isostructural nitrilo-tris-methylenephosphonate complexes of transition metals of 3d-series [MII(H2O)3μ–NH(CH2PO3H)3] (MII = Cr–Zn) are analyzed. It is shown that the correlation of force constants with interatomic distances is in good agreement with the Badger rule, and the break energy of bond M ← OH2 deviates strongly from the empirical Poling dependence. It is shown that deviations of the break energy of bond M ← OH2 from the Poling rule are due to the presence of an uncompensated spin density at the central atom. This explains the stability of Fe-containing heterometallic coordination polymers [(Fe,M)(H2O)3μ–NH(CH2PO3H)3], which determines the high efficiency of nitrilo-tris-methylenephosphonate complexes as inhibitors of the corrosion of steel in aqueous media.

The Novosibirsk FEL facility has three FELs installed on the first, second, and fourth orbits of the multiturn energy recovery linac (ERL). The first FEL covers the 90–240 μm range of wavelengths at an average radiation power of 0.5 kW with a pulse repetition rate of 5.6 or 11.2 MHz and a peak power of 1 MW. The second FEL operates in the 40–80 μm range of wavelengths at an average radiation power of 0.5 kW with a pulse-repetition rate of 7.5 MHz and a peak power of around 1 MW. These two FELs are the world’s most powerful (in terms of average power) sources of coherent narrow-band (less than 1%) radiation in their wavelength ranges. The third FEL was commissioned in 2015 to cover the 5–20 μm range of wavelengths. The Novosibirsk ERL is the world’s first and only multiturn ERL. Its distinctive features include a normally-conductive 180 MHz accelerating system, a direct current (DC) electrostatic electron gun with a control grid and thermionic cathode, three operating modes of the magnetic system, and a compact (6 × 40 m) design. The Novosibirsk FEL facility has been in operation for users of terahertz radiation since 2004.

The universal cell mediator nitric oxide (NO) mediating the physiological effects via so-called NO donor compounds prolonging its life time. The concentration of NO metabolites in the pancreatic juice of chicken was determined by the enzymatic sensor. It was found that pancreatic juice from starved birds contains nitrate and no other nitro- or nitroso compounds. After feeding, the NO donors appear in pancreatic juice in concentrations of a few tens of μM. These compounds were present in pancreatic juice for several hours after feeding. It is possible that NO donors promote relaxation of the smooth muscles in the walls of pancreatic ducts. Concentration of NO donors in blood serum also increased 2.5–3.0-fold after feeding and remained high during a few subsequent hours. The preliminary subcutaneous administration of atropine to the birds prevent this increase with no effects on the initial concentrations of NO donors in serum. This suggests that the increase is associated with cholinergic stimulation and, therefore, with the activity of the parasympathetic nervous system. The concentration of trypsin in serum also increased after feeding, and atropine also prevents this increase. It is known that serum trypsin acts as a regulator of pancreatic function. Intravenous administration of trypsin led to an insignificant increase of tryptic activity in serum but induced the increase of NO donor concentration twofold. Apparently, nitric oxide, represented by these compounds, can act as a humoral factor in the regulation of pancreatic function in pancreatic juice and possibly in the blood.

Circuit breakers are one of the most widespread electrical devices in control and distribution systems that use electric energy fluxes, providing protection from short circuits and current overloads. First and foremost, circuit breakers should provide a high operation speed at shutdown, which can be achieved with low weight and significant electromagnetic forces. For approximate determination of magnetic system dimensions, network analysis methods are used. In addition, the model of magnetic field structure can be substantially simplified. The conductivity of air gaps between the ferromagnetic elements of a magnetic system can be described by a modified method of probable paths of magnetic flux, and the resistance of ferromagnetic elements (magnetic potential drop) is taken into account by means of a mathematically expressed magnetization curve (for steel of 10895 grade).

Reducing the weight of the materials used in the creation of electromagnetic devices and decreasing the overall size of the latter greatly increases the attractiveness of low-voltage switchgear such as relays, contactors, and motor starters. These goals can be achieved by forced control of their driving electromagnets and the development of a technique for minimizing weight and size. In this paper, these problems are solved for a shell-type plunger constant-voltage electromagnet used as a drive. For the preferred region of the factor space of the source design data, a computational experiment was performed in accordance with a second-order orthogonal central composite design for eight variables. The polynomial models were developed for an optimal relative proportionality of a working air gap, the winding height and thickness, the outer collar height in fractions of an optimal core diameter, and the stop height in winding fractions. Examples of the calculation of the optimal electromagnet size minimizing its overall volumetric dimensions are given.

The actinometric system installed aboard the Yak-42D "Roshydromet" research aircraft is presented. It is designed to study radiation processes in the troposphere. The system is based on standard Kipp&Zonen actinometric instruments for measuring solar, thermal, and ultraviolet radiation fluxes as well as on specially developed radiation models with high-precision methods for solving radiative transfer equations (Monte Carlo, k-distribution, and line-by-line calculations). The combination of actinometric measurements and detailed simulation of radiative transfer in the atmosphere allows examining the radiation balance components throughout the troposphere using in situ measurements at the aircraft location. Some results of studying radiation fluxes obtained during the flights over the Arctic region of the Russian Federation are presented. The data of measurements carried out using the presented system are useful for validating radiation codes utilized in general atmospheric circulation models and for processing satellite remote sensing data.

This paper shows that the inflammation-induced appearance of nitrite and nonthiol nitroso compounds in the hen blood and cow milk is due to oxidation of dinitrosyl iron complexes (DNIC) and nitrosothiols (RSNO) by reactive oxygen species (ROS), which are produced by activated leukocytes. Since DNIC and RSNO are highly effective ROS scavengers, the content of nitrite and nonthiol nitroso compounds can be regarded as one of the most sensitive indicators of leukocyte activation.

Huntite-like EuM 3(BO3)4 crystals (M = Al, Cr, Fe, or Ga) are synthesized by means of spontaneous crystallization from a solution in a melt. The infrared spectra of the compounds are measured. The experimental data and the results from ab initio DFT calculations are compared. The comparison shows that the compounds have a primarily noncentrosymmetric rhomboherdal structure with the R32 space group. This indicates these compounds could exhibit magnetoelectric and nonlinear optical properties.

A heteroleptic complex of molybdenum with nitrilotris(methylenephosphonic acid), hydroxylamine, and nitrogen(II) oxide is investigated via single-crystal X-ray diffraction (SXRD) and X-ray photoelectron spectroscopy (XPS). It is established that the actual charge on the Mo atom is around +1e, despite the formal oxidation state of molybdenum being +3. The electron density is mostly localized in the Mo–NO bond, and the distribution of the electron density is indicative of the formation of a π-bond.

Nitrilo-tris-methylene-phosphonato-three-aqua-complexes of chromium(II) and iron(II), the main components of protective layers for inhibiting steel corrosion with nitrilo-tris-methylene-phosphonates, are isolated and studied. Their ability to form protective layers is explained by their insolubility and resistance to water and air. These properties of Cr and Fe complexes are explained by Jahn–Teller distortion of the coordination environment of Cr and Fe atoms.

The determination of petrophysical parameters in conjunction with the geological, structural, mineralogical, and petrographic study of rocks is necessary to assess the localization conditions of uranium–molybdenum ore, the processing prospects, and the extent of mineralization at the Antey vein–stockwork deposit, which is the Russia’s largest, confined to the granitoid basement of the Streltsovo Caldera in the Southeastern Trans-Baikal Region.

A two-point contact model in robotic assembly is considered, in a quasi-static formulation. In the experiments, a robot equipped with a force and torque sensor is employed. The consistency of theoretical analysis with physical experiments is discussed.

Heteropolynuclear [Zn0.5Fe0.5(H2O)3{NH(CH2PO3H)3}] n and [Cd0.125Fe0.875(H2O)3{NH(CH2PO3H)3}] n complexes, which form during interaction between inhibitors of corrosion and Fe2+ ions and play an important role in inhibiting local steel corrosion by complexes of nitrilotrismethylenephosphonic acid, are isolated for the first time. Their composition, structure, and properties are studied by means of XSA, EDRS, IR and Raman spectroscopy.

Sufficient conditions for the applicability of the law of the iterated logarithm to sequences of dependent random variables are obtained. As a corollary, a theorem on the law of the iterated logarithm for a sequence of m-orthogonal random variables is proved.

A manufacturing technology has been developed for the mechanochemical synthesis of hard-alloy plates from titanium and tungsten carbides; the plates are intended for use in cutting tools. Test results for the mechanical properties of the alloys are presented.

The kinetics of coke deposition on catalysts for the hydrotreating of fuel fractions depends on the method used in sulfiding the catalysts. Synchronous thermal analysis may be applied to the coking of sulfided hydraulic-purification catalysts. A method is outlined for sulfiding of the catalyst used in hydraulic purification by means of tertiary butylpolysulfide in a high-pressure laboratory catalytic system. In addition, a method for the coking of sulfided and unsulfided catalysts outside the catalytic reactor is described. Optimal conditions are selected for thermogravimetric analysis in the identification of soot particles by means of the STA 409 PCLuxx instrument.

New data on the isotope age of metamorphic rocks of the Taratash and Aleksandrovka Complexes are given and all the available isotope data of these rocks are reviewed. It is established that the age of the stratified part of the Taratash Complex is Late Archean to Early Proterozoic (>2000 Ma) and plutonic rocks are of Early Proterozoic age, approximately corresponding to that of migmatites of the Taratash Complex. The Taratash and Aleksandrovka complexes are most likely of the same age.

Nanocomposite films of Co-containing polyacrylonitrile (PAN) films were manufactured using the method of pyrolysis under incoherent IR-radiation and were studied using AFM, XPS, and XRD atomic force microscopy (AFM), X-ray photoelectron spectroscopy (XPS), and X-ray diffraction (XRD) methods. The XPS method was used to determine the elemental composition and the chemical and electron states of the elements of the film material. The XRD method showed that the obtained materials contained crystalline inclusions of CoO, Co3O4, and CoO(OH) in an organic matrix of PAN. The AFM method revealed that the film surfaces have high values of the mean square roughness of R q = 10.4–53.1 nm, which linearly depend on the concentration of the modifying additive in the film material. It was established that the films of Co-containing PAN have semiconducting properties and are sensitive to NO2, Cl2, and CO.

In this paper, we present the summarized results of investigations that concern the construction of geographic information systems (GISs) for modeling purposes to enable the spatial-temporal analysis and qualitative assessment of situations. Due to the strengthening of requirements for the control of geodynamic characteristics, which is due to a marked decline in the environment and industrial safety (first and foremost, for objects of especial importance), modeling information systems are created that allow one not only to trace but also to predict the development of a situation using visual models. Global trends in the development of three-dimensional (3D) modeling of the geoinformation systems used in Earth sciences are considered. As basic technologies, we selected information technologies of network-based analytical GISs, the distributed computing technology, the technology for visual 3D modeling, and Internet technology. As an example of using the proposed modeling method, we cite the results of investigating objects of increased technogenic and ecological hazards in the Transbaikal sector of the Mongol-Okhotsk mobile belt.

The mechanochemical synthesis on tungsten carbide on the basis of carbon obtained by plant pyrolysis is considered.

The production of functional nanocomposites on the basis of plant matter and minerals is considered. Such nanocomposites are promising as anodes in lithium polymer batteries, as sorbents, and as carbon sources in the synthesis of titanium carbides.

Several different methods for diagnosis of Crimean-Congo Hemorrhagic fever virus (CCHFV) are proposed in this work. We show that the ELISA-based diagnostic kits based on CCHFV recombinant antigens produced by E. coli cells still possess a few substantial shortcomings that are yet to be addressed. In this work, we present the development of a unique CCHFV-detection system fully based on reverse transcription—a nested two-step polymerase chain reaction (RT-PCR). Our RT-PCR-based diagnostic kit for CCHFV detection is now commercially available. We also developed a simple screening method for samples potentially containing CCHFV, which is based on analysis of restriction fragment length polymorphism (RFLP) analysis of amplicons and allows preliminary genotyping of the CCHF isolates.

Mossbauer spectra of the solid solutions and iron-containing phases that precipitate upon isothermal annealing in beryllium-based alloys with different impurity concentrations are obtained and fitted using the equation of convolution of three Lorentz lines. The possibility of performing a consistent analysis of decomposition of the solid solution using the Avrami classification and precipitation of the secondary phases based on diffusion growth models is demonstrated.

A fiber-optic polarization interferometer with two electrooptic elements (sensor and additional modulator) designed for measuring electric field intensity is suggested and analyzed. The paper focuses on the theoretical and experimental demonstration of the principles of operation of fiber-optic circuits that generate and process the optical signals and provide measurement. The advantage offered by our interferometer is that it allows, in contrast to conventional configurations, additional modulation of the phase difference between interfering waves by a modulator in the instrumental part of the device and the use of available methods of phase detection developed for fiber-optic interferometric sensors. A laboratory prototype has been successfully tested.

Attention focuses on the processing of sphagnum moss and the sequence by which multiwalled carbon nanotubes are formed in the mechanical activation of amorphous carbon. Nanotube formation occurs within a mass of carbon particles.

A problem of aeroelastic interaction between gas and a cylindrical structure in the course of supercharging is considered. To analyze the processes progressing in the system gas-deformable solid body, the unified difference method is implemented. The stress-strain state and gas-dynamic processes are analyzed with the use of the space-time mesh that is common for the gas and structure.

Some results of activities on cloud seeding operations to modify the weather conditions over metropolises are given. The main objective of these activities was to dissipate the clouds and to decrease or to stop the precipitation on the territory under protection during the political, cultural, or sporting events. Up to 12 aircraft specially equipped with the measuring equipment needed to carry out the cloud seeding, with the Land-Aircraft-Land radio data transmission system, and with the cloud seeding means were used to fulfill the works on the weather modification. The liquid nitrogen, “dry ice”, silver iodide, and coarse-dispersion powder were used as the reagents for the cloud seeding. To control the aviation works and the results of the cloud seeding, the ground-based automated meteorological radar systems were used. The results of more than 40 large-scale operations on the improvement of weather conditions carried out since 1995 in different regions of Russia and near abroad indicate the efficiency of the methods and technical means of cloud seeding developed by the specialists of Roshydromet to modify the atmospheric precipitation.

The effect of plasma cleansing on the surface state of samples studied by electron microscopy is experimentally investigated. This technique of sample preparation allowed diagnostics of the magnetic states of objects by scanning electron microscopy with the analysis of spin polarization of secondary electrons.

New sufficient conditions for the applicability of the strong law of large numbers are established for sequences of random variables without the independence conditions. Results on strong stability of sums of dependent random variables are also obtained. No particular type of dependence between random variables of a sequence is assumed. Only conditions related to moments of random variables and their sums are used. It is shown that the results obtained are unimprovable in certain sense. These results are generalizations of some results of N. Etemadi proved under more restrictive conditions.

The description is given of the modern conception and of technical means to carry out the weather modification activities in megalopolises using the active influencing methods. The main objective of these activities is the cloud dissipation and the decrease or cessation of precipitation on the territory under protection. Four influencing methods are commonly used depending on the synoptic situation. To carry out the meteorological protection activities, the airplanes are used equipped with the measuring equipment necessary to execute the influencing, the “land-aircraft-land” system of the radio data traffic and the cloud seeding means. The liquid nitrogen, solid carbonic acid, silver iodide, and coarse-dispersion powder are used as the cloud seeding reagents. To control the aviation activities and the results of cloud seeding, the ground automated radar meteorological complexes are used.

The effect of irradiation by an argon ion beam with a broad energy spectrum and an average energy of 10 keV in a dose range of (1−10) × 1018 ion cm−2 on the state of iron atoms in the near-surface layers of zirconium alloys Э635, NSF, and Zry-2 was studied by means of conversion electron Mossbauer spectroscopy (CEMS).

The efficiency of operating wind power plants in combination with forest plantations is examined.

The counter mixing of a strong circularly polarized wave of optical pump with a weak phase-modulated signal wave on the reflection grating formed by them in (111)-, (110)-, and (100)-cut Bi12TiO20 and Bi12SiO20 phototrefractive crystals was theoretically and experimentally studied.

The content of the isotopes 3H, 14C, 36Cl, 55Fe, 59Ni, 63Ni, 60Co, 90Sr, 93mNb, 108Ag, 133Ba, 134Cs, 137Cs, 154Eu, and 155Eu in the GRP-2-125 graphite from the reactor of Power Unit 2 at the Chernobyl Nuclear Power Plant was measured. The results were compared with the calculations and literature data. Some regularities and correlations were revealed in the content of various radionuclides in graphite. Graphite porosity and desorption of radionuclides from graphite were studied.

Some new possibilities of modeling the dependences of the monochromatic cathodoluminescence intensity on the electron beam energy for a three-layer direct-gap semiconductor structure (where the diffusion of minority charge carriers can be described within the independent-source model) are considered.

Criteria and indices of the degree of degradation of the vegetation cover are established. The limiting effect of abiotic factors on productivity of degraded pastures is determined.

We suggest efficient methods for studying stress concentrations in thin-walled structural members. The advantages of these methods are determined by their essential distinguishing characteristics as compared with well-known methods. After the separation of variables, the solution of linear ordinary differential equations of shell strain mechanics is analytically determined in the form of a matrix Taylor series. The property of the solution to satisfy arbitrary initial conditions allows one simply to reduce the boundary conditions to the initial conditions prior to calculating. Another method for structures with arbitrary parameters of the shells permits one to transfer the boundary conditions by a multiplicative method to the stress concentration site and to use them as the initial conditions in studying the stress concentration. We present the results of investigations of the stress concentration in transport-launch containers of aircraft by various methods.

The weather modification technologies designed to mitigate hail damage for economic and social objects become more and more demanded, despite ambiguous estimates of their results and thus expediency of their practical use [15, 17]. In this connection, results of antihail work in the areas where this activity lasts for many years are of direct scientific and practical interest. The Republic of Moldova is a good example of such an area. Antihail shield, based on the rocket technology of reagent injection into the cloud, has been under operation for more than 40 years. In the paper, the conceptual basis of hail-dangerous Cb cloud modification technique are presented along with some data on modification results during the last 10 years; an optimistic estimate of the antihail shield efficiency in the country is obtained.