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—The geological environment of ore formation in sandstone-type uranium deposits is considered in light of modern geomicrobiological and ecological (environmental) mineralogical data related to solving environmental bioremediation problems (purification of the near-surface environment via bacterial fixation of radionuclides). Analysis of the literature data shows the possible ore-forming role of the biogenic factor in the formation of infiltration sandstone-type uranium deposits, which is considered here with an example of their paleochannel subtype with widespread phosphate black uranium ores. The bacterial factor is proposed as one of the main mechanisms for the occurrence and movement of the redox front during hypergene processes in ore-bearing sedimentary sandstone strata.

The relationships between local indices at stations in the Russian sector and the planetary Ap and Kp indices and the potential to evaluate planetary indices based on local values are studied. It is shown that the local indices of observatories in western Russian make it possible to estimate the values of the global indices rather well. Estimates of global indices based on data from the central and eastern stations of the Russian sector are less reliable, but this may be due to the lack of Kp-network observatories and stations in this sector, as well as underestimation of the global geomagnetic activity at 0900–1500 UT based the Kp index itself.

The fluorination of elementary substances and inorganic and organic compounds with elementary fluorine is accompanied by high heat release (of about hundreds of kilojoules per mol of fluorine), which determines the high probability of their implementation in the unsteady-state temperature mode (combustion or thermal explosion mode) when the temperature of the process products is close to adiabatic, and a significant part of the released heat is removed from the obtained substances outside the reaction zone. If target fluorides are present in the thermodynamically equilibrium mixture of substances in an element system that contains fluorine at a temperature close to the adiabatic temperature, fluorination in the combustion mode is successfully used in industry. Otherwise, it is reasonable to perform fluorination in the steady-state (close to isothermal) temperature mode by removing the heat of the reaction from the reacting mixture directly in the reaction zone. This publication considers the efficiency of application of the steady- and unsteady-state temperature modes in the fluorination of various substances with elementary fluorine.

The dependence was studied of the level of density fluctuations recorded at different devices on the minor and major radii of the tokamak. It is known that a high level of density fluctuations can negatively affect the operation of diagnostics, in particular, the plasma reflectometry diagnostic. The increase of density fluctuations decreases the quality of raw data by increasing the error of measuring the density profile and, when density fluctuations exceed the threshold value, it renders such measurements impossible. Based on experimental data obtained on devices with substantially different sizes, a dependence of the density fluctuation level on the major and minor tokamak radii was proposed. Since the main experiments were carried out in round limiter tokamaks in ohmic (OH) heating regimes, the extrapolation result is applicable, generally speaking, to installations of larger size with the same configuration and regimes. However, experiments with electron cyclotron heating at the T-10 tokamak also allow one to extend the obtained dependence to regimes with auxiliary heating. It was shown that the obtained dependence is applicable to limiter tokamaks Tore Supra and TFTR of larger size. The applicability of the dependence to installations with diverter configuration is discussed and the possible level of density fluctuations is extrapolated to the international reactor tokamak ITER that is being constructed in France.

Research data on the content of radionuclides in the near-surface soil layer (up to 10-cm-thick) of the territory of New Moscow, which was a part of Moscow oblast until 2012, are presented. Such studies of this object have not been performed until now. The analysis of the radioecological status of the area considered is urgent due to the intensive development of its infrastructure and building. We have already performed a radioecological assessment of the area using aerogamma-spectrometric survey maps. The analysis of the content of radionuclides (137Cs, 40K, 232Th, 226Ra, and 238U) in the soil cover by the gamma-spectrometric method is used in order to refute or confirm the results obtained previously. Conclusions about the radioecological status of the soil cover of New Moscow and about the effect of economic objects on general radiation conditions are made.

A method for measuring the relative amount of gas released from the magnetron during its vacuum pumping is presented. Equations describing three main reactions during pumping are obtained. The developed method is tested on model objects and used to measure the relative amount of gas released from a serial magnetron during vacuum pumping. The efficiency of pumping out the magnetron is analyzed for various methods of degassing. A method is proposed for accelerating desorption-diffusion processes when the magnetron body is treated with ultrasonic vibrations simultaneously with its heating during vacuum pumping, which increases the gas release efficiency more than twofold.

The results on elastic proton–proton scattering that were obtained by the TOTEM Collaboration at the LHC (Large Hadron Collider) energy of 13 TeV are analyzed. It is shown that the statistical significance of these results is questionable in some respects. Specific examples show that the parameter $$\rho$$ extracted from experimental data is model-dependent.

In modern large-sized tokamaks and those under construction, for example, in ITER, when measuring the average plasma electron density using the refractometry technique, it becomes necessary to study different effects that affect the measurement accuracy. This paper presents the results from studies of the high-temperature effects that can affect the interpretation of delay time measurements of the probing microwave signal in the ITER refractometry diagnostics. The criteria for applicability of different plasma models (“cold” plasma, modified “cold” plasma, and “hot plasma”) are obtained for calculating the plasma refractive index and interpreting the delay times that will be measured using the refractometry diagnostics of the ITER plasma. In the second article, based on the results obtained in this article, we will consider the influence of the high-temperature effects on the accuracy of determining the mean density using the refractometry diagnostics.

In this paper, the influence of the interference of electron waves during their reflection from a rectangular semi-infinite potential barrier to the spatial distribution of quantum mechanical current density еjx(x, z) (e is the electron charge and jx(x, z) is the flow of probability density) in a semiconductor 2D nanostructure is theoretically studied. The structure consists of narrow and wide rectangular quantum wells (QWs) arranged successively along the direction of electron wave propagation. It is assumed that the wave falls from narrow QW1 on a potential barrier of height V0 in wide QW2. It is shown that when a wave with energy less than V0 falls on the barrier, then, in certain conditions, spatially inhomogeneous distribution $$ej_{x}^{{\left( 1 \right)}}(x,z)$$ oscillating in a complicated way exists in QW1. An exponential attenuation and coordinate dependent leakage $$ej_{x}^{{\left( 2 \right)}}(x,z)$$ under the barrier may occur in QW2. It is shown that this behavior of $$ej_{x}^{{\left( 1 \right)}}(x,z)$$ and $$ej_{x}^{{\left( 2 \right)}}(x,z)$$ is caused by the interference of electron waves propagating through different quantum-dimensional subbands in the considered nanostructure.

In order to develop a scientifically grounded technology for production of porous getters, there appears the necessity to apply highly sensitive methods for determining the activation temperature, which are compatible with the standard magnetron pumping technology. In this study, a complex technique for determining the activation temperature for porous getters is proposed using the experimental scheme simulating the conditions of porous getter activation in accordance with the standard exhaust tube pumping technology. Under the conditions of the simulation of physicochemical processes in the volume of the heated magnetron housing under pumping, the model of the formation of a gas load on the interior pumping equipment is considered. It is shown that, according to the theory of composite chemical reactions, thermal desorption flows are generated by either the theory of consecutive reactions or the theory of parallel-consecutive reactions. The sorption capacity of porous getters is determined from a plot as the time–temperature dependence of the mass yield of composite chemical reactions of interaction between the gas load and the surface and bulk of a getter tablet. A getter tablet’s change in mass is recorded using the microbalance of a vacuum thermogravimetric unit uninterruptedly at the frequency of one measurement a second throughout the entire period of measurements. The sensitivity threshold of the microbalance is 10–5 g and the maximum mass is 5 g. Using the theory of parallel-consecutive reactions, for the first time, the minimum temperature of thermal activation of a porous getter of a Ti–V (30 at %) alloy is determined, which is the main technological parameter when interior pumping equipment is employed. For the nonisothermal part of the standard heat treatment plot, at the heating rate of 10°C/min and the specified vacuum conditions, the minimum activation temperature is 393°C. For estimating the changes in the roughness of the free surface of a getter washer subjected to interior saturation in a hydrogen medium, scanning electron microscopy is used. Cracks and microsized tetragonal single crystals are found, which might be titanium hydrides TiН2. It is established that crack formation has a positive effect on the getter’s sorption activity due to the appearance of new atomically clean surfaces. However, cracking can contribute to the crumbling of the getter tablet. Therefore, the hydrogen gas load is the factor that limits the durability of the getter.

Perigean spring tides in the atmosphere are discussed. In 2016–2017, the smoothed anomalies of air temperature over European Russia were found to repeat the evolution of the distance of the perigee (i.e., the distance between the Moon and the Earth at times when the former is at the perigee), which varies as a sine function with a period of about 206 days. The origin of the 206-day lunar cycle is described. Atmospheric spring tides are studied. They are exhibited as atmospheric pressure oscillations similar to perigean spring oscillations of the sea level. The basic dependence of perigean spring tides in the form of beats of atmospheric pressure anomalies at new and full moons is found. The pressure anomalies at full and new moons can be approximated by sinusoids with beat envelope periods of about 412 days and with opposite phases. The range of oscillations at antinodes reaches 40 mb, which is comparable, in order of magnitude, with actual mesoscale fluctuations of atmospheric pressure. The violations in seasonal weather variation caused by the 206-day lunar cycle are described.

Reduction of optical quantum sensors in size, including nuclear magnetic resonance (NMR) gyroscopes, implies primarily downsizing of the working gas cell. This paper considers the dependence of isotope shift in the balanced scheme based on NMR in xenon isotopes on the dimensions of the gas cell. With this aim in view, an experimental and theoretical studies of the factors affecting the relaxation rate of xenon isotopes have been carried out. The proposed numerical model allows predicting the magnitude of the isotope shift for cells of various sizes with variations in their basic parameters, namely, temperature and pressure of the gas mixture. Based on the results of the numerical simulation, recommendations are given for optimizing the basic parameters of the gas cell by changing its dimensions.

New data on the geological structure and ore-bearing structural parageneses of the Uryakh gold ore field are presented. The formation of the deposit occurred in dynamic shear regime along ore-controlling deep-seated faults of the Syulban fault system and faults of the system transverse to it. The interaction of two duplex shear systems resulted in the block structure of the ore field. Tectonophysical methods have established the individual development of tectonic blocks during the period of gold-bearing fluid input in a seismically active regime. The specific features of the formation of ore-bearing fracture–fault structural parageneses in the blocks resulted from the change in the seismic regime under the action of pressure and gas-saturated fluids. The parameters of the fluid system were determined by fluid inclusion studies in quartz. An unstable variable compression–extension regime of the early phase of seismic activity led to the formation of hybrid structural parageneses under the influence of stresses of damping shear and injective hydrodynamic stress. Variations in the stress–strain state of the medium in this phase correspond to a transient seismic regime and are consistent with variations in the thermobarometric parameters of the fluid system. In the late phase of seismic activity, a stable uniaxial tension regime with a superlithostatic fluid pressure occurred, which caused brittle deformations independent of slip along the fault. The centroid mechanism of such deformations, which is rarely found in the dynamic regimes of hydrothermal deposits, ensured the formation of structural parageneses unusual for shear zones, which resulted in a different combination of structural and morphological types of orebodies in the blocks.

We discuss the extent to which the often assumed independence of the phase of the elastic scattering amplitude from momentum transfer in the domain of only small $$t$$ constrains the dependence of the phase on $$t$$ in general. Based on analyticity, we prove that if the scattering amplitude phase is independent of the transferred momentum in the domain of its small values in strong couplings, then this remains the case in the whole physical domain. Moreover, if such independence holds in any domain of physical energies including values infinitely close to the first inelastic threshold from below, then the whole scattering amplitude vanishes. We also discuss the relation between the dependence of the phase on $$t$$ and the size of the interaction domain.

A sodium salt of samarium nitrilotris(methylenephosphonate) complex [Na(H2O)6]2[SmH{μ7-N(CH2PO3)3}2Na6(H2O)10] · 6H2O has been synthesized, isolated, and studied. Crystals are monoclinic, space group P21/c, Z = 2, a = 11.8046(2) A, b = 10.5454(2) A, c = 19.8116(3) A, and β = 94.2790(10)°. The Sm atom is coordinated to two acid residues {N(CH2PO3)3} bound to each other through six P–O–Na–O–P bridges. The Sm coordination polyhedron is a rhombohedron elongated along the N–Sm–N axis. The Sm–O bond length (2.379(10) A) is 0.615(12) A smaller than Sm–N (2.9944(19) A), which is explained by back donation of Sm–O bonds and generation of an increased electron density region in the vicinity of the Sm atom.

Isomerization of liquid hydrocarbons to obtain high-octane components of gasoline fuels in superacid catalytic media based on the trimethylamine hydrochloride–aluminum chloride ionic liquid with the addition of various salts was studied. The density, viscosity, and thermal stability of the catalytic systems obtained were studied. Regular trends in the influence of the physicochemical properties of the catalysts and experiment parameters on the catalytic activity of the systems were revealed.

Dispersed radioactive ore mineralization (uranium blacks) in paleovalley deposits of the Vitim uranium-ore region (Buryat Republic) has been studied by a set of methods of analytical electron microscopy (SEM, TEM).The ore component, tetravalent uranium phosphate ningyoite, in the form of micrometer crystalline mineraloid precipitations is represented in all kinds of host rocks (sands, bedding granites, overlapping basalts). The previously little known phosphate-black uranium ores are new-for-Russia type of industrial ores.

Analysis of the dynamics of modern desertification of the Northwestern Caspian with the use of geoinformation technologies and aerospace data showed that the area of degraded and desertified lands in the region increases due to an increase in the anthropogenic factor (pasture load). With a relatively stable number of animals, the role of climatic factors increases, which leads to an increase in the speed and amplitude of changes in the area of desertification foci, both in the direction of a decrease with sufficient moisture and an increase in dry years. A significant influence is exerted by fires, which lead not only to a decrease in projective cover but also to a depletion of the species composition of vegetation. The study and mapping of the relief made it possible to establish spatially defined geomorphological features of the territory as a factor affecting local moisture and, accordingly, the stability of ecosystems and the possibility of phytomelioration.

The features of a feedback loop in a quantum sensor with a two-frequency spin oscillator are discussed. Engineering solutions that ensure stable two-frequency oscillation and, in particular, the use of automatic gain control units and all-pass filters are considered. The results of experimental studies of oscillation modes conducted on a quantum sensor breadboard are presented for stationary and rotating bases.

A sodium salt of the complex of nitrilo-tris(methylenephosphonic) (NTP) acid with Mn(II) (Na4[MnII{N(CH2PO3)3}] · 13H2O, sp. gr. P$$\bar {1}$$, Z = 2, a = 11.2146(4) A, b = 11.2687(4) A, c = 12.4625(4) A, α = 108.619(3)°, β = 97.149(3)°, γ = 116.991(4)°) has been synthesized and investigated. This complex is binuclear with a chelate structure; the Mn coordination polyhedron is a distorted trigonal bipyramid with three O atoms of different PO3 groups of the NTP molecule in the base, with the nitrogen atom of the NTP molecule in one vertex, and the O atom of the neighboring NTP molecule in the opposite vertex. The crystal packing is of island type; Mn polyhedra share (pairwise) edges and are surrounded by a spatial binding of Na polyhedra and water molecules.

Integral equations on the semiaxis with kernels having the form of a linear combination of the Fourier sine and cosine transforms with arbitrary variable complex coefficients are considered. For the case in which the coefficients depend on only one variable, exact solutions are presented. Various generalizations and applications to integral equations are given.

The characteristic features of the manifestations of acid magmatism and metasomatic hydrothermal alteration processes in Southeastern Transbaikalia, an important mining region in Russia, are discussed. The zoned or beltlike distribution of the ores of various metals, uranium in particular, and other mineral deposits is due to the general evolutionary trends of the geodynamic regimes of the respective blocks of the territory and the subsequent magmatic differentiation trends. The highly differentiated and fluorine-rich granitoids of Southeastern Transbaikalia are located only in the zones of the consolidated crust, which are characterized by low gravity and negative quiet magnetic field values. In other zones, i.e., volcanic belts, volcanogenic troughs, and the regions dominated by the intrusive massifs of the Shakhtama complex, rare metal manifestations are absent. It was demonstrated that there is no correlation between the localization of large uranium deposits and leucocratic rare metal granite domains and that these deposits are concentrated in large volcanic calderas or volcanic troughs, controlled by long-lived fault systems. In addition to uranium, these volcanogenic structures control base metal, molybdenum, gold, fluorite, and some other mineral deposits. The results of a comparative analysis of the geochemical features of the acid volcanics that host the uranium mineralization and are classified as the last differentiation products of the contrasting latite volcanism, on the one hand, and the subvolcanic and hypabyssal derivatives of the rare metal granites, on the other, are presented. The analysis revealed the signatures of their fundamental difference from each other and that they belong to different branches of magmatic differentiation. A comparative analysis of the metasomatic aureoles of the altered wallrocks in the Late Mesozoic volcanics and the Shakhtama granitoid domains, on the one hand, and the leucocratic rare metal granite domain, on the other, is given. The data presented attest to the existence of a mixed geodynamic regime within the study area of the Central Asian mobile belt during the Jurassic and the earliest Cretaceous time: residual collisions with strong deformations in a compressional setting, accompanied by the development of late acid differentiation products of the magmatic latite series, and the incipient rifting associated with the intrusion of the leucogranites of the Kukul’bei complex in a more quiet extensional setting.

The investigation of the gas sensitive properties of an array of nanorods of zinc oxide obtained by hydrothermal synthesis is carried out. Their morphology and crystal structure as well as electrophysical and gas sensitive properties are studied. A thermodynamic analysis of the process of interaction of carbon monoxide (CO) with the surface of the nanorods of zinc oxide is performed based on the experimentally determined activation energy of conductivity and gas sensitivity coefficient. It is shown that the process under study includes an interaction between a CO molecule and a charged adsorption site of the surface of zinc oxide.