Common fractions N1/N2, where N1 and N2 are small integers, are quite often used for a quantum-mechanical description of microcosm objects (for example, fractional charges of quarks and some quantum characteristics, such as particle spins). Recently the fractional quantum Hall effect has been discovered, and the common fractions considerably expand their presence in microcosm physics. The theory of

Collective acceleration of protons and deuterons is compared in the same geometry of a Luce diode with a polyethylene anode at an accelerating diode voltage of 250 kV, current and pulse duration of relativistic electrons up to 30 kA and 90 ns, respectively. The accelerated ions were intercepted by B4C, BN, and AlN wafers, in which analytical radionuclides were produced according to the nuclear reactions

This paper is a generalization of two of our preceding papers which considered, among other things, a version of the solution with a minimum and a maximum number of atoms in the spatial configurations 1+2+3. Some results of these works, pertaining to probabilistic transitions of atoms from one configuration to another, follow from the results of the given paper as a special case.

Aiming at the reduction of low-frequency noise for large equipment, a damping optimization method based on the Operational Mode Analysis (OMA) is proposed. Due to the stability of the mode frequencies and shapes, damping application could make efficient noise reduction without bringing new problems compared with structural optimizations, which makes it one of the most important means for finalized

The special features of the second harmonic generation by a spherical nanoparticle with a plasmon shell are theoretically studied. Within the framework of quasistatic perturbation theory, expressions are derived for the induced dipole and quadrupole moments of the particle oscillating with a doubled frequency. The second harmonic radiation power has been calculated showing the resonance nature of the

At the Institute for Laser and Plasma Technologies of NRNU MEPhI, a compact spherical tokamak MEPhIST (MEPhI-Spherical Tokamak) has been developed and constructed for educational, demonstrational and research purposes. The creation of plasma diagnostic systems involves several stages, determined by a successive complication of the plasma research tasks, the device upgrading and the development of educational

The paper presents the development of the statistical theory of phase transformation of lithium aluminum amide with the formation of ammonia. Free energies of phases are calculated, and their dependences on temperature, pressure, hydrogen concentration and energy parameters are suggested. The phase diagram is suggested and thermodynamic equilibrium is calculated herein. Isothermal processes in phases

In order to overcome the problems of long analysis time, low accuracy, and high energy consumption in traditional lateral vibration analysis methods of high-rise buildings, a new method of lateral vibration analysis of high-rise buildings based on partial differential equation is proposed. Based on Hamilton’s principle, the partial differential equation of lateral vibration of high-rise buildings is

The characteristics of the multiple filamentation domain of femtosecond laser pulses in air have been estimated based on the single filamentation model. The diffraction-ray model is considered as the single filamentation model. It is based on representation of a laser beam by a set of diffraction-ray tubes nested into each other that do not intersected in space and do not exchange by their energies

The curvature and torsion of trajectories of charges in external gauge fields, including fields of magnetic monopoles, have been determined. It has been shown that these quantities are effectively calculated with the help of the equations of motion and first integrals. For a wide class of magnetic fields, their form-invariant combination has been revealed.

Results of studies of the luminescent properties of MgF2 ceramics and MgF2 ceramics doped with tungsten trioxide synthesized in air upon exposure to a pulsed electron beam are presented. The photo- and cathodoluminescence spectra and the photoluminescence excitation spectra have been studied at 300 K both in as-prepared samples and in the samples after high-temperature annealing in air. The presence

The paper shows that the structure constant and the average crystal grain size of anisotropic nanocrystalline magnetic film can be determined by analyzing the shape of the microwave absorption peak in sweeping the external magnetic field along the hard magnetization axis. In the theory of magnetization ripple, the surface energy density of the local magnetic anisotropy is connected with the structure

In the CeO2, ThO2, and NpO2 crystals, the acoustic branches of the phonon spectra correspond predominantly to the vibrations of metal ions, and the optical branches correspond mainly to the vibrations of oxygen ones, due to a significant difference in the masses of these components of the compounds. An important crystallographic phenomenon is that metal and oxygen are located in sublattices corresponding

The paper presents the results of the transmission electron microscopy of the evolution of the dislocation substructure (DSS) of the polycrystalline ordered and disordered Pd3Fe alloys with low-stable structure and phase compositions. A flow chart is suggested for the transformation of the dislocation substructures during a transition from one stage to another. These stages are indicated on the stress-strain

A new approach is proposed for designing a system of automated positioning of the engineer reconnaissance devices under dynamic reception conditions with a low GPS signal/noise ratio. An analysis is performed of the classical positioning methodology based on the GPS signal tracking, and a more efficient approach based on a Kalman filter modification is proposed. A comparative analysis of the tracking

Analytical description of generation of undulator radiation (UR) harmonics is given with account for the effects of finite electron beam size, emittance, off-axis beam deviation, and electron energy spread as well as of constant magnetic components and field harmonics. Exact analytical expressions obtained for the generalized Bessel and Airy functions describe the spectrum line profiles and the UR

The processes of plasma formation in the anode region of a high-current vacuum arc discharge are of high importance in terms of improving the switching characteristics of vacuum circuit breakers. In this paper the radiation spectrum dynamics in the anode region is recorded with a system allowing for time scanning of the spectrum. Concurrently, high-speed videorecording of the process is performed.

Numerical solution of the wave parabolic equation on a rectangular grid is analyzed when the discrete split-step Fourier transform (FT) method is used to calculate the field values in an inhomogeneous medium on the next step in the range. The goal is to find out the limiting possibilities of the FT method itself, so studies have been carried out for radio wave propagation in free space only. Two related

The paper presents investigations of the structure, phase composition and properties of the rail running after bulk steel hardening. Investigations are performed at a different depth by using modern techniques of material physics in extremely long operation conditions (gross weight of 1411 million tons). The Rockwell hardness measurements at a depth ranging from 2 to 10 mm, show a decrease in the hardness

The vacuum-arc plasma-assisted method is used to deposit a multilayer coating based on Ti and Al in two discharge systems – in a traditional plasma-assisted vacuum-arc spraying system and in a gas-metal beam-plasma generation system in a hollow cathode of a non-self-sustained low pressure glow discharge. The coatings synthesized in these discharge schemes have close elemental and phase compositions

Spectral dependences of components of the refractive index and absorption coefficient in a Li2B4O7 (LB4) nonlinear crystal are determined in the THz range for the first time. Measurements have been carried out in the 0.15–1.6 THz (180–2000 μm) spectral range. The measured refractive index components are approximated by the Sellmeier dispersion equations subsequently used to determine the possible interaction

The paper focuses on the void swelling processes in materials subjected to radiation, that occur due to the formation of the void ensemble in the crystal lattice. According to the theoretical analysis of the kinetics and the pore size distribution with regard to the defect migration, the numerical calculations are performed for void swelling in nickel.

The possibility of increasing the sensitivity of the mercury vapor analyzer in ambient air using a capillary lamp with a natural mercury isotopic mixture in the presence of the transverse Zeeman effect as a radiation source has been experimentally studied. Lamp radiation is stabilized by separate control of temperatures of the capillary and lamp bulb. The obtained sensitivity of the analyzer reached

The theoretical and experimental data determining the similarities and differences between the defect formation processes under the conditions of neutron and imitation ion irradiation are analyzed. The analysis involves such factors as the type and energy of cascade-forming particles, the composition and structure of irradiated materials, and the irradiation temperature. A number of proven procedures

The paper focuses on the synthesis of NiCo/C nanocomposites comprising the Ni–Co alloy nanoparticles uniformly distributed and stabilized in a carbon matrix. The synthesis is performed by using IR pyrolysis of organometallic precursors obtained from a mixture of dymethylformamide solutions of polyacrylonitrile, nickel and cobalt chloride hexahydrates. It is shown how the synthesis temperature and the

When studying the properties of various physical objects, experimental data often contain gross errors (outliers) which can lead to significant distortions of the results of statistical processing of such data. For this reason, statistical procedures are being developed that are protected from the presence of outliers in observations. In this paper, two types of robust estimates of the scale parameter

The paper investigates the influence of interstitial carbon and oxygen atoms on their diffusion along the <111>, <100> and <110> tilt grain boundaries in face-centered cubic nickel and silver. It is shown that in most cases, the impurity addition leads to the growth in the self-diffusion coefficient along the grain boundaries due to the crystal lattice distortion near the impurity atoms, thereby causing

A unified approach is developed for calculating the profiles of the spectral lines of atoms in an alternating electric field on the basis of diagonalization of the energy matrix of an atom in the field. To calculate the Stark profile of the spectral line, a formula is proposed in which the profile width contains an explicit dependence on the parameters of the electric field. The algorithm of the method

The different translational symmetry of the cuprite crystal sublattices is taken into account by unfolding the phonon spectrum from the Brillouin zone of the crystal into the Brillouin zones of the anion and metal. Such a representation of the spectrum is reasonable because 6 optical branches are essentially caused by the vibrations of anions and 12 acoustic branches are due to the vibrations of metal

The paper studies superelasticity in a 203–523 K temperature range of the 42.5Fe-34Mn-15Al-7.5Ni-1Ti at.% oligocrystals quenched and aged at 473 K for 3 hours. It is shown that the critical stress for the stress-induced α-γ' martensitic transformation slightly grows with the test temperature increasing in accordance with the Clausius–Clapeyron relation. The value of α = dσcr/dT characterizing this

The structure and optical properties of titanium dioxide films have been studied during annealing from 100 to 400°C. The films were obtained by ion-plasma high-frequency magnetron sputtering of polycrystalline rutile target in an argon atmosphere. It was shown that as-prepared TiO2 films are nanostructured with ~8 nm rutile crystallites and ~3.3 Å interplanar distances and contain a small fraction

Beale’s nonlinearity estimation algorithm is adapted for solving asteroid problems. It has been tested for model and actual asteroids. It is shown that this algorithm underestimates the nonlinearity. Modifications of Beale’s nonlinearity measure are considered that allow its accuracy to be increased.

Results of studies of the electric-discharge KrF laser with a specific pulse energy of ~6 J/L and an internal energy efficiency of more than 4% are presented. The formation of instabilities of various types in the volume discharge from an initial inhomogeneity of the electric field in the discharge gap and the partial composition of the gas mixture are shown. The possibility of stable discharge burning

The gauge dependence of an effective action with composite fields is investigated for general gauge theories arising in the functional renormalization group approach. It is shown that at any finite scale of the IR cutoff, this action is independent of the gauge fixing conditions at their extrema.

Coherent optical transition radiation (COTR) from femtosecond electron bunches is simulated using an earlier proposed model. It is shown that partial screening of the COTR field followed by focusing with a lens allows increasing the spatial resolution and makes it possible to measure transverse bunch sizes accurate within a few microns. It is demonstrated that the most reasonable lens screening ratio

The effect of blood adhesion on the amplitude-frequency characteristics of a piezoelectric sensor in the method of low-frequency piezothromboelastography is studied. As a result of adhesion, a layer of blood cells can accumulate on the surface of the resonator needle immersed in blood, which changes its configuration and mass and, as a consequence, its amplitude-frequency characteristics. Experiments

With the help of a successful scheme for overcoming difficulties arising for l ≠ 0 in the centrifugal part of the Rosen–Morse potential with bound states, a solution of the modified Klein–Fock–Gordon equation is found. The energy eigenvalues and the corresponding radial wave functions are found for an arbitrary value of the orbital quantum number ( l ≠ 0 ).

The water-cooled WWR-K research reactor has been operating since 2016 using low-enrichment uranium fuel. In order to maintain high levels of generated power and reactivity margin sufficient for a 21-day operation cycle, the water-cooled core reflector of neutrons was gradually, depending on the fuel burnup, replaced by a beryllium one in order to prevent decreasing of the reactor performance. A series

Sodium fluorouranates were studied to get the refined value of one of the fundamental constants with determination of differences between various uranium isotopes contained in these compounds. Such compounds as sodium heptafluorouranate can be classified as molecular substances with covalent bonds. The approach to the assessment of decomposition temperature of sodium fluoride compounds with various

With the help of the classical Boltzmann kinetic equation, a correction to the Navier–Stokes equation has been found in the form of a biharmonic term in the Laplace operator. It is shown that upon taking this term into account, corresponding corrections in the Knudsen number appear in the Stokes formula.

Combinational circuit C composed of gates and its sub-circuit with set V of output nodes and set U of input nodes are considered. The set V consists of output nodes of fault gates of the circuit C (only logical faults are examined) and fault free gates, the inputs of which are at the same time lines in that Trojan circuit payloads are injected. A procedure of forming the set U, as a rule, depends on

To the article “Influence of Porosity on Fracture Toughness of Hydroxyapatite/Multi-Walled Carbon Nanotubes Biocomposite Materials,” by A. N. Ponomarev, M. S. Barabashko, A. E. Rezvanova, and E. P. Evtushenko, Vol. 63, No. 11, pp. 1885–1890, March, 2021.

The results of a study of thermal conductivity and specific heat capacity of Zr – 1 wt.% Nb and Ti – 45 wt.% Nb alloys in coarse-grained and ultrafine-grained states are presented. The influence of the utrafinegrained state on the thermophysical properties and the processes of energy dissipation and accumulation during deformation of the alloys are estimated. It is shown that the formation of an ultrafine-grained

A configuration and test samples of photoconductive dipole antennas based on SI-GaAs:Cr and LT-GaAs for generation and detection of terahertz radiation are developed. Their operating characteristics in the pulsed mode and in the mode of operation as photomixers are experimentally investigated.

The motion of the asteroid (469219) Kamo`oalewa, which moves in 1:1 mean motion resonance with the Earth, is investigated. Over the course of studying the dynamics of this object, we revealed close approaches to planets of the Solar System and mean motion and secular resonances and estimated the chaoticity of its orbit. A peculiarity of the asteroid motion is its regular transitions from the state

The overview of scientific literature on the electric and magnetic properties of AlN doped with transition metal group atoms is presented. The review is based on the literature sources published mainly in the last 10 years. The doping was carried out by various methods: during the material growth (molecular beam epitaxy, magnetron sputtering, discharge techniques) or by implantation into the grown

The linear-circular dichroism of two- and three-photon absorption of light in semiconductors of hole conductivity with cubic symmetry is theoretically investigated. The matrix elements of two- and three-photon optical transitions occurring between the subbands of the semiconductor valence band are calculated. Transitions associated with both non-simultaneous absorption of individual photons and simultaneous

The results of a study of features of the surface scale growth on the V–Cr–Ta–Zr vanadium alloy specimens during short-term oxidation in air are presented. It is shown that in the initial oxidation stages, irrespective of the specimen microstructure, the surface scale growth rate can be an order of magnitude higher than that in the course of long-term treatment. It is found out that the scale is characterized

An experimental and theoretical study of electrical conductive properties of the vestibular labyrinth tissues is carried out. Using the theory of dynamic systems and experimental data on the measurements of amplitudes of electrical signal at the end of the vestibular nerve, the transfer function of the vestibular labyrinth is calculated and its frequency dependence is investigated. It is shown that

A modulated pseudo-Hermitian optical dimer is investigated. The parameter ranges are determined where the eigenmodes of the dimer conserve their power. It is shown that such a dimer has several exceptional points, and it is found that the dimer modes can conserve their average power over the period even if each of its segments is in the PT-broken phase. On the other hand, even if each segment is in

Approximate formulas of the phosphorescence decay kinetics have been obtained for the statistical distribution of molecules over the rate constants of radiative and non-radiative deactivations of triplet excitations. It is shown that the characters of the phosphorescence decay differ for these two cases. The obtained difference in the kinetics has been used to establish a reason for the deviation from

The paper studies the influence of thermal treatment of the structure and properties of the composite coating consisting of chromium and titanium carbides and obtained by nonvacuum electron beam melting. It is shown that the coating tempering leads to a decrease in the microhardness and wear resistance. This is because the austenitic structure decomposition with the formation of the soft ferrite-carbide

The paper considers the dynamics of changing of misoriented dislocation substructures appearing at a stage of developed plastic deformation. The types of defects, which induce the distortion of the crystal lattice are studied in detail. The quantitative parameters are obtained for the lattice distortion in alloys at a different grain size. It is found that the lattice bending and torsion parameters

The influence of a dark energy model – a new nonvacuum field – has been considered here for the first time in the generalized Roche potential with the equivalence principle taken into account for interacting galaxies. An equation of the thermodynamics of the indicated field is derived and its possible evolutions, influencing the accelerated expansion of the Universe, are discussed.

Based on the classical quantum-mechanical approach, the physical mechanism of isotope fractionation is proposed associated with the predominance of a certain number of neutrons among nucleons and explaining the nonequilibrium accumulation of certain stable isotope shapes of biogenic elements in heterogeneous systems. The effect may be due to the interaction of the magnetic moments of atomic nuclei

The adsorption of nitric oxide NO molecules on the surface of structurally ordered 1, 2, and 3 monolayer thick nickel films deposited on the W(110) surface has been studied by the method of reflection-absorption infrared spectroscopy. The structure of the nickel films of all examined thicknesses correspond to that of the Ni(111) crystal. The IR spectra of the NO molecules adsorbed on a 3-monolayer

Special aspects of nucleation and development of plasticity in nanocrystalline BCC-iron during shear are studied. The mechanisms of plastic deformation playing the key role in structural rearrangements during loading are revealed. It is shown that the development of plasticity can be conventionally divided into several stages. The first stage of plasticity evolution is associated with the formation

The paper studies the structure and phase composition of steel 0.12C–1Cr–1Mo–1V–Fe (grade DIN 14MoV63) after a long-term operation using the transmission electron microscopyю Investigated are the nontreated specimen (not subjected to operation) and specimens after a long-term operation with and without fracture. The phase composition and morphology of the steel structure are determined for each specimen

The paper presents the results of the computational modeling and quantum-chemical investigations of metal-polymer composites based on pyrolyzed polyacrylonitrile (PAN) consisting of the ternary Fe–Ni–Co compound. The proposed model of pyrolyzed PAN monolayer contains three atoms of iron, nickel, and cobalt instead of eight atoms of the basal polymer substance. Determined are the geometry and electronic

The paper analyzes the influence of porosity of hydroxyapatite (HA)/multi-wall carbon nanotubes (MWCNTs) composites on their fracture toughness. It is found that two competing factors affect the resulting fracture toughness. On the one hand, MWCNTs, which are stronger than the surrounding HA matrix, promote the increase in the fracture toughness owing to the possible crack path deflection from the