bluuebunny/crossref_metadata_2025 huggingface dataset:
The Dynamic Properties of Low-Alloyed Copper Alloys with a Submicrocrystalline Structure Obtained by High-Strain-Rate Deformation
Authors: Abdullina D. N. , Khomskaya I. V. , Razorenov S. V. , Shorokhov E. V.
Published: April 2024

Abstract—The mechanical properties of alloys Cu–0.03 wt % Zr and Cu–0.10 wt % Cr with a submicrocrystalline structure formed during dynamic channel-angular pressing and subsequent annealing. The properties of the alloys were studied under shock compression conditions with a pressure of 4.7–7.0 GPa and a deformation rate of (1.3–3.2) × 105 s–1. It is shown that grain grinding from 200–400 to 0.3–1.0 microns increases the dynamic elastic limit and the dynamic yield strength of the Cu–0.03% Zr alloy by 1.9 and 1.8 times, respectively, but reduces the shear strength by 1.4 times. Subsequent annealing at 400 and 450°C can increase the characteristics of the elastic-plastic transition by 3.0 and 3.7 times, respectively, and increase the shear strength to the level of a large-crystal analog. It is determined that the dispersion of the Cu–0.10% Cr alloy structure to 1.0–5.0 microns increases not only the dynamic elastic limit and dynamic yield strength by 3.7 and 2.6 times, respectively, and the shear strength by 1.5 times, compared with its value in the coarse-grained state.
A Study of the Structure and Magnetic Properties
of the Soft Magnetic Ni80Cr20 Alloy Manufactured
by Additive Technology
Authors: Zhukov A. S. , Manninen S. A. , Tit M. A. , Olisov A. V. , Knyazyuk T. V. , Kuznetsov P. A.
Published: April 2024

The effects of heat treatment on the structure and magnetic properties of the 80NHS grade permalloy produced by selective laser melting (SLM) of gas-atomized powder are presented in comparison with the properties of the rolled 80NHS alloy. Ring samples either produced by SLM or machined from rolled metal have been studied. It has been established that the magnetic properties of the SLM samples are inferior to the properties of samples produced by thermomechanical processing because the structure of the additivelymanufactured alloy is characterized by fine grains and a large number of nonmetallic inclusions.
Second Phase Particles in Zr–Sn–Nb–Fe Alloys: A Review
Authors: Aldeen A. V. , Chen Z. V. , Disher I. A. , Samiuddin M. , Yan K.
Published: April 2024

In the Zr–Sn–Nb–Fe quaternary alloys, the nature and evolution of the second phase particles (SPPs) is critical to the performance of the alloy in the extremely deteriorative environment. The main aimof this review consists in summarizing the fundamental results of the identification and characterization of the SPPs in the Zr–Sn–Nb–Fe alloys. Emphasis was placed on the importance of composition, identification,crystallographic structure, formation mechanism, and state and stability of several SPPs in these alloys. Identical compositions in ternary Zr–Nb–Fe intermetallics have been identified as C14 HCP Zr(Nb,Fe)2 orC15 FCC (Zr,Nb)2Fe structure. Zr(Nb,Fe)2 is often reported, while, the cubic phase (Zr,Nb)2Fe is easily distinguished.The reliability of R* parameter, which is specified by Nb/Fe physical ratio in determining the SPPs types in different composition range of Zr–Sn–Nb–Fe alloys, is discussed with reasons. The influence and the role of O and Cr in the formation and stability of ternary Zr–Nb–Fe intermetallics are also clarified. Finally, thermodynamic stability of SPPs was also taken into consideration in the current review.
The Submonolayer Structure of Ni(111)–(√3 × √3)R30–Pb:
Atomic Relaxation and Vibrational Properties
Authors: Borisova S. D. , Rusina G. G.
Published: April 2024

The results of a theoretical study of the structural and dynamical parameters of surface phases (adsorption phase and surface alloy phase) formed upon the adsorption of 0.33 Pb monolayer on the Ni(111) plane surface are discussed. Calculations were performed using interatomic potentials obtained within the framework of the embedded atom method. The stability of the surface phases was analyzed on the basis of data on the equilibrium atomic configuration, phonon spectra, local density of phonon states, and polarization of localized vibration modes. It is shown that the Pb–Ni surface alloy has the highest dynamic stability among the two possible surface phases.
Influence of the Shape of a Spin-Tunnel Element
on the Dependence of Its Magnetoresistance
Authors: Amelichev V. V. , Vasilyev D. V. , Polyakov P. A. , Kostyuk D. V. , Belyakov P. A. , Kasatkin S. I. , Polyakov O. P. , Kazakov Yu. V.
Published: April 2024

A theoretical and experimental study of the dependence of the magnetoresistance for two spin-tunnel junctions (STJs) of ellipsoidal shape has been made. The one-sided homogeneous magnetization reversal mode of an ellipsoidal STJ with different aspect ratios has been experimentally selected. Despite the reverseinhomogeneous remagnetization, this selection has allowed for the calculation of the magnetic parameters of these elements by developing the Stoner-Wohlfarth theory.
THE MICROSTRUCTURE AND MECHANICAL PROPERTIES OF THE Al–Mg–Fe–Ni–Zr–Sc ALLOY AFTER MULTIDIRECTIONAL FORGING
Authors: Kishchik A. A. , Aksenov S. A. , Kishchik M. S. , Demin D. O. , Churyumiv A. Yu. , Mikhaylovskaya A. V.
Published: April 2024

The influence of multidirectional isothermal forging on the grain structure and secondary phase particles of solidification origin and dispersoids in Al–4.9Mg–0.9Ni–0.9Fe–0.2Zr–0.1Sc alloy has been studied. The finite element simulation was used to analyze a strain distribution in the sample during forging in a die. A proposed method considered the influence of friction and the changes in a strain rate to recalculate true stress-strain curves for multidirectional forged alloy. An increase in a number of forging cycles at a temperature of 350°C ensured a twice decrease in a mean size of the particles of solidification origin, provided a mean grain size of 1.3 ± 0.2 μm, and insignificantly changed the size of dispersoids. The isothermal multidirectional forging increased the yield strength of the alloy by 60%, tensile strength by 20%.
Secondary Phases in MgB2 Superconducting Ceramics
Authors: Kuznetsova E. I. , Krinitsina T. P. , Blinovaa Yu. V. , Degtyarev M. V.
Published: April 2024

Secondary phases have been revealed in the course of development of approaches to obtaining the superconducting MgB2 ceramic. These secondary phases are identified, and the mechanisms of their generation are thoroughly discussed. It is shown that a complex of methods, including the optical microscopy inthe polarized light, scanning and transmission electron microscopy, provides opportunities for describing the secondary phases in the MgB2 ceramic, especially when they cannot be determined only by X-ray analysis.
The Influence of Frictional Treatment
and Low-Temperature Plasma Carburizing on the Structure
and Phase Composition of Metastable Austenitic Steel
Authors: Savrai R. A. , Skorynina P. A. , Makarov A. V. , Men’shakov A. I. , Gaviko V. S.
Published: April 2024

The features of the structure and phase composition of corrosion-resistant austenitic chromium–nickel steel (16.80 wt % Cr, 8.44 wt % Ni) subjected to carburizing in electron beam plasma at temperatures of 350 and 500°C, frictional treatment with a sliding indenter, and a combination of frictional treatment and plasma carburizing have been considered. It has been established that plasma carburizing results in the formation of a modified surface layer consisting of carbon-saturated austenite and carbides (Cr23C6, Fe3C); in this case, the formation of γC-phase occurs only at a temperature of 350°C. The depth of a modified layer increases with an increase in the carburizing temperature. It has been shown that it is useful to perform combined frictional treatment and plasma carburizing at a carburizing temperature of 350°C, since in this case the deformation-induced structure formed as a result of frictional treatment is preserved, and the precipitated carbides remain highly dispersed. In this case, frictional treatment should provide the formation of the deepestpossible diffusion-active layer with a dispersed structure.
Simulation of the Three-Component Potts Model
on a Hexagonal Lattice by the Monte Carlo Method
Authors: Babaev A. B. , Murtazaev A. K.
Published: April 2024

Computer simulation of the three-component Potts model on a hexagonal lattice was carried out using the Monte Carlo method. Systems with linear dimensions L × L = N, L = 10–320 in units of interatomic distances are considered. Based on the theory of finite-size scaling, the static critical exponents of heat capacity α, susceptibility γ, magnetization β, and correlation radius ν are calculated. The data we obtained confirm that in the considered Potts model on a hexagonal lattice, a second-order phase transition is observed with critical exponents corresponding to the universality class of the three-component Potts model.
Calculating the Relative Variances of Magnetization,
Heat Capacity, and Susceptibility in a Two-Dimensional Weakly
Diluted Four-Component Potts Model
Authors: Ataeva G. Ya. , Babaev A. B. , Murtazaev A. K.
Published: April 2024

The relative variances of the magnetization Rm, heat capacity Rc, and susceptibility Rχ are calculated by the Monte Carlo method in the spin lattice four-component weakly diluted Potts model on a square lattice at a spin density p = 0.80. It is shown that introducing a disorder in the form of nonmagnetic impurities into the 2D Potts model leads to nonzero values of Rm, Rc, and Rχ at the critical point. It has been found that these values decrease noticeably for systems with linear sizes L ≥ 120 interatomic distances.
MD Simulations of Collision Cascades in α-Ti. The Residual Number of Radiation Defects, Cascade Relaxation Time and Displacement Cascade Region Morphology
Authors: Voskoboynikov R. E.
Published: April 2024

Molecular dynamics (MD) simulations were applied to study radiation damage formation in collision cascades created by the recoil of primary knock-on atoms (PKA) with PKA energies Epka = 5, 10, 15, 20 and 25 keV in α-Ti at temperatures T = 100, 300, 600 and 900 K. A series of 24 collision cascades with the same set of (Epka, T) parameters has been simulated to generate representative sampling. Sapling size was justified a posteriori. The number of Frenkel pairs Nfp and cascade relaxation time were obtained as functions of (Epka, T). It was shown that the average ⟨Nfp(Epka,T)⟩ fits within 0.3NRT, provided the threshold displacement energy is chosen in 28-40 eV range depending on the irradiation temperature. Under high PKA energy/low irradiation temperature conditions, displacement cascade region splits into subcascades expended along high-energy recoil trajectories. Cascade relaxation time does not depend on Epka in this case. Contrary, under low PKA energy/ high temperature simulation conditions, most of collision cascades possess equiaxial shape, and their relaxation time grows with PKA energy increase.
Change in the Radius of the First Coordination Sphere in Amorphous Alloys during Deformation
Authors: Abrosimova G. E. , Astanin V. V. , Volkov N. A. , Gunderov D. V. , Postnova E. Yu. , Aronin A. S.
Published: April 2024

Changes in the structure of amorphous alloys under deformation by high-pressure torsion, multiple-pass rolling, and pressure treatment have been studied using X-ray diffraction and scanning electron microscopy. It has been shown that under all types of deformation, shear bands are formed in amorphous alloys, which are regions of lower density compared to a surrounding undeformed amorphous matrix. Shear bands are regions of an increased free volume; the formation of bands results in steps occurring on the surface of samples. The number of shear bands and the surface morphology of deformed amorphous alloys are determined by the deformation type and physical properties of a material.
Martensitic Transformation and the Electrical and Magnetic Properties
of Ni51 – хMn36 + хSn13 (0 ≤ х ≤ 4) Alloys
Authors: Kaletina Yu. V. , Gerasimov E. G. , Terent’ev P. B. , Kaletin A. Yu.
Published: April 2024

The structures and electrical and magnetic properties of Ni–Mn–Sn-based alloys are studied.Changing the crystal lattice type in the course of martensitic transformation is found to be accompanied by substantial changes in the electrical resistivity. It is shown that for all the alloys under study negative magnetoresistanceis observed. The maximum magnetoresistance in a magnetic field of 18 kOe of ≈–45% was foundfor the Ni47Mn40Sn13 alloy.
A System of Josephson Vortices in a Layered Electron-Doped Nd2 – xCexCuO4 Superconductor
Authors: Charikova T. B. , Shelushinina N. G. , Klepikova A. S. , Popov M. R.
Published: April 2024

A brief review of the transport and galvanomagnetic properties of an electron-doped Nd2 – xCexCuO4 layered superconductor with an emphasis on the role of the structure of Josephson vortices formed in the crystalin a magnetic field oriented in the parallel direction to the CuO2 planes is given. The experimental data on the longitudinal and Hall magnetoresistance of the recently synthesized Nd2–xCexCuO4/SrTiO3 epitaxial films are analyzed. The possibility of formation of a system of Josephson vortices in this highly anisotropic system is determined by the unique orientation of the c axis and the conducting CuO2 planes of the Nd2 – xCexCuO4 compound with respect to the substrate plane.
Grain Boundary Diffusion of 57Co in Ultrafine Grained Niobium Processed by Severe Plastic Deformation
Authors: Popov V. V. , Osinnikov E. V. , Istomina A. Yu. , Popova E. N. , Falahutdinov R. M.
Published: April 2024

Grain-boundary diffusion of Co in ultrafine-grained Nb processed by severe plastic deformation by high-pressure torsion has been studied by layer-by-layer radiometric analysis. Coefficients of grain-boundary diffusion for several temperatures have been determined. It is shown that diffusion along grain boundaries proceeds much faster than in coarse-grained niobium with relaxed boundaries, which is explained by the formation of "non-equilibrium" grain boundaries under the severe plastic deformation, which are the paths of ultrafast diffusion. Recovery processes occur in non-equilibrium grain boundaries under heating, due to which their properties approach to those of conventional high-angle boundaries in the coarse-grained material.
Helimagnetic and Crystallographic Growth Textures of Dysprosium Nanolayers on Co90Fe10, Nb, and β-Ta Buffer Layers
Authors: Naumova L. I. , Zavorпitsyn R. S. , Milyaev M. A. , Devyaterikov D. I. , Rusalina A. S. , Krinitsina T. P. , Pavlova A. Yu. , Proglyado V. V. , Ustinov V. V.
Published: April 2024

Dysprosium nanolayers of various thicknesses are made by magnetron sputtering on Al2O3 (R) substrates, as well as using buffer layers Co90Fe10, β -Ta and Nb. The correlation between the crystallographic texture and the peculiarities of the temperature dependence of the electrical resistance of polycrystalline dysprosium films was investigated. It was found that when Dy is sputtered directly on Al2O3 (R), a two-component texture is formed in the nanolayer of the rare earth metal. In one component, the hexagonal axis is parallel and in the other, it is perpendicular to the plane of the film. It has been shown that when Dy is sprayed on the buffer layer β -Ta, the microstructures of Al2O3 and Dy are matched through β -Ta, and the perfection of the two-component texture increases. In the antiferromagnetic state, the texture components become phases with different orientation of the magnetic helicoid axis, and the formation of antiferromagnetic ordering occurs at different temperatures.
The Electronic Structure, Thermoelectric, Optical Properties
of Heusler Alloys Mn2MeAl (Me = Ti, V, Cr)
Authors: Shreder E. I. , Filanovich A. N. , Chernov E. D. , Lukoyanov A. V. , Marchenkov V. V. , Stashkova L. A.
Published: April 2024

The results of calculations of the electronic structure, thermoelectric characteristics, and an experimental study of the thermoelectric, electrical, and optical properties of Mn2MeAl Heusler alloys (Me = Ti, V, Cr) are presented. The agreement between theory and experiment in the sign of the Seebeck coefficient is shown. The obtained pattern of the band spectrum allows us to qualitatively explain the peculiarities of the temperature dependences of the electrical resistance and the permittivity dispersion.
STRUCTURAL-PHASE STATUS OF HIGH ENTRICITY NbTiHfVZr ALLOY
Authors: Abzaev Yu. A. , Guda S. A. , Guda A. A. , Zelenkov A. A. , Kolesnikov V. I.
Published: April 2024

The paper presents the results of the high entropy alloy NbTiHfVZr stability study based on the analysis of critical Yum-Roseri indices, enthalpy of double alloys by Miedema method, entropy of mixing of NbTiHfVZr compound near the melting temperature. The method of inverse convex shells (InveseHubWeb) found temperature stability intervals, which for the compound NbTiHfVZr extend from the melting temperature to 1200K. In the case of NbTiHfZr the temperature stability interval extends up to room temperature. The obtained results indicate that the compounds NbTiHfVZr, NbTiHfZr belong to the high entropy lattices of which belong to the class of single-phase single-element solid solutions. Prediction of the lattices by the evolution code in the USPEX code made it possible to detect from the base of 300 standards, several simple cubic lattices with the spatial group P1 and different spatial distribution of atoms, which lattice energy turns out to be negative. The totality of the results obtained indicates that the found standards can be attributed to the stable phases in the corresponding temperature stability intervals of the compounds NbTiHfVZr, NbTiHfZr.
Nonuniformity of
magnetization processes of a cobalt-based amorphous alloys in the as-quenched state
Authors: Skulkina N. A. , Nekrasov E. S.
Published: April 2024

The magnetization processes nonuniformity of an amorphous cobalt-based soft-magnetic alloy AMAG-172 (Co-Ni-Fe-Cr-Mn-Si-B) in the as-quenched state were studied. Studies have shown that the main reason of the magnetic characteristics and magnetization processes nonuniformity is the nonuniformity of internal stresses due to the alloy manufacture method. An indirect characteristic of internal stresses is the domains volume with orthogonal magnetization. The observed bimodal field dependence of the magnetic permeability and the field shift of the hysteresis loops in the region of 180-degree domain walls displacement are a consequence of the nonuniformity of the alloy over its thickness. The field shift and the asymmetry of hysteresis loops are explained in terms of the formation of a unidirectional exchange anisotropy at the interface between the ferromagnetic and antiferromagnetic phases of the planar magnetization components oriented along the ribbon axis. The field shift disappearance and the asymmetry of the hysteresis loops along the width of the tape can be interpreted as a decrease in the thickness of the CoO oxide antiferromagnetic layer due to the difference in the concentrations and depth of oxygen and hydrogen atoms penetration induced into the surface of the tape during the manufacture of the tape as a result of interaction with atmospheric vapor.
Effect of frictional treatment and low temperature plasma carburizing on the microhardness and electromagnetic characteristics of metastable austenitic steel
Authors: Savrai R. A. , Skorynina P. A. , Makarov A. V. , Kogan L. Kh. , Menshakov A. I.
Published: April 2024

Microhardness and electromagnetic characteristics of corrosion-resistant chromium-nickel (wt. %: 16.80 Cr; 8.44 Ni) austenitic steel subjected to electron beam plasma carburizing at temperatures of 350 and 500°C, frictional treatment with a sliding indenter and combined treatments, including frictional treatment and plasma carburizing have been investigated. It has been found that plasma carburizing increases the microhardness of the steel surface from 200 to 1100 HV0.025. The total hardening depth was 25 microns after carburizing at T = 350°C and 300 microns after carburizing at T = 500°C. Frictional treatment increases the microhardness of the steel to 600 HV0.025 with a total hardening depth of 500 microns. It has been shown that the diffusion-active layer with a dispersed structure formed during preliminary frictional treatment contributes to additional hardening of the steel (up to 1275 HV0.025) during subsequent low-temperature (350°C) carburizing. Combined treatment with carburizing at a temperature of 500 °C increases the microhardness of the steel to 820 HV0.025, and the total hardening depth is 500 microns for both combined treatments. It has also been found that plasma carburizing of the steel leads to a decrease in the eddy-current readings compared to the quenched steel and their growth compared to the steel subjected to frictional treatment, which can be used to develop quality control techniques for such treatments.
Nanosize Dependence of the Mutual Solubility in the Solid State in the Mo–Ru Metal System
Authors: Afashagov A. A. , Shebzukhova M. A. , Bzhikhatlov K. Ch. , Tsipinova A. Kh.
Published: April 2024

Abstract—The present work is devoted to constructing a method for calculating the solubility curves of molybdenum and ruthenium in the solid state in the binary Mo–Ru system with consideration of nanoscale effects. The approach is based on the thermodynamics of phase equilibria, taking into account the surface phenomena within the framework of the Gibbs thermodynamic method of separating surfaces. The surface tension is chosen as such a separating surface. The calculations of solubility were performed taking into account the dimensional dependences of the individual characteristics of metals and the parameters of interparticle interaction in the phases. A good agreement of the obtained results with the available experimental data for the macroscopic case is observed.
Evolution of the Structure and Phase Composition of a High-Entropic CoCrFeNiCu Alloy during Prolong Annealing
Authors: Poliakov M. V. , Kovalev D. Yu. , Volkova L. S. , Vadchenko S. G. , Rogachev A. S.
Published: April 2024

Abstract—The thermal stability of a high-entropy alloy (HEA) CoCrFeNiCu was studied during long-term annealing for 204 days in the temperature range 873–1273 K. The alloy obtained by mechanochemical alloying of metal powders in a planetary mill during 120 min in an Ar environment is a substitutional solid solution based on a high-entropy phase with a face-centered cubic structure (FCC). Upon annealing, the initial FCC phase decomposes within 1–3 days into a copper-enriched FCC1 phase and a copper-depleted FCC2 phase with similar crystal lattice parameters of 3.60 and 3.57 Å, respectively. During the entire annealing time, the intensities of the diffraction lines of theFCC1 and FCC2 phases are redistributed, the dynamics and nature of which depends on the temperature and duration of the process. After the first three days and until the end of the annealing, the HEA retains the FCC structure of the substitutional solid solution, and the unit cell parameters of the formed FCC phases remain constant with an error of 0.1% up to 204 days. The five-component matrix formed after annealing has the chemical composition Co0.23Cr0.23Fe0.23Ni0.23Cu0.08 and is stable. Also, during the entire period of annealing, an increase in the grain size is observed: at first, when an active rearrangement of the structure occurs, the size increases rapidly, then, in the period from 1 to 30 days, grain growth is limited by the diffusion of components, and at very long time intervals, grain growth is even more inhibited.
Study of supersaturated solid solution decomposition during quenching of sheets from Al-Mg-Si aluminum alloy
Authors: Benarieb I. , Puchkov Yu. A. , Sbitneva S. V. , Zaytsev D. V.
Published: April 2024

This paper presents the results of a study of the stability of a supersaturated solid solution (SSS) of sheets made of thermally hardened aluminum alloy of the Al-Mg-Si system with a small addition of copper (Al-0.6Mg-1.0Si-0.2Cu) under various quenching modes. The samples were subjected to isothermal or continuous quenching with different quenching cooling rates, after which artificial aging was carried out at a temperature of 170°C. From the results of thermodynamic modeling of the equilibrium phase composition of the alloy, it was found that for the temperature range from 300 to 530°C, the presence of the β-phase (Mg2Si) is most likely. With the use of transmission electron microscopy and X-ray spectral microanalysis, it was found that during quenching, the decomposition of SSS leads to the precipitation of undesirable large particles of metastable β-type phases or equilibrium β-phase. The nucleation of the secretions is realized in the form of rod-shaped particles by a heterogeneous mechanism mainly on the surface of the α-phase dispersoids (Al15(Mn,Fe)3Si2), which thus significantly increase the quenching sensitivity of the alloy. The formation of these secretions at a low quenching rate causes, during subsequent aging, a decrease in the proportion and density of formation of strengthening particles of the β" phase, and also leads to an increase in their size and heterogeneity of distribution in the aluminum matrix, which reduces the potential of dispersion hardening during aging and corrosion resistance of the material.
Atomistic Simulation of
Symmetric and Asymmetric Tilt Grain Boundaries 5 <001> in Niobium: Structure, Energy, Point Defects,
Grain Boundary Self-Diffusion
Authors: Stupak M. E. , Uгazaliev M. G. , Popov V. V.
Published: April 2024

Symmetric and three asymmetric tilt grain boundaries Ʃ 5 in niobium have been studied by computer simulation methods. The structure and energies of the boundaries under consideration, as well as the energies of the formation of point defects in them, are calculated by the method of molecular-static modeling. The dependences of the formation energies of point defects on the distance from the plane of the grain boundary are analyzed. Using the method of molecular dynamics, the coefficients of grain-boundary self-diffusion for the considered boundaries are calculated.
Baric Transformation of the Nature of Magnetic Ordering and Magnetocaloric Properties in the Mn1 – xCrxNiGe System
Authors: Valkov V. I. , Golovchan A. V. , Gribanov I. F. , Andreychenko E. P. , Kovalev O. Ye. , Mitsiuk V. I. , Mashirov A. V.
Published: April 2024

Abstract—The isobaric temperature dependences of the magnetization and the magnetocaloric characteristics of alloys of the Mn1 – xCrxNiGe system are studied in a constant magnetic field up to 10 kOe in the range of hydrostatic pressures up to 12 kbar. It has been established that, with increasing pressure, the implementation of helimagnetic ordering undergoes qualitative changes from smooth hysteresis-free 2nd order phase transition to 1st order phase transitions, accompanied by the appearance of a temperature hysteresis and an increase in the magnetocaloric effect. Based on the exchange-structural model, an explanation is given for the mechanism of baric transformation of magnetic and magnetocaloric properties.
Thermal Conductivity and Thermal Diffusivity of Iron in the Temperature Range of 300–1700 K
Authors: Agazhanov A. Sh. , Samoshkin D. A. , Stankus S. V.
Published: April 2024

Abstract—Using the laser flash method, the thermal diffusivity (a) of carbonyl iron is measured in the temperature range of 300–1700 K with a detailed study of the critical region 980–1170 K. The initial experimental data in the field of magnetic phase transformation are processed by the scaling power law. The values of the critical indexes for thermal diffusivity (\(\gamma {\kern 1pt} ',\) γ) are obtained below and above the Curie temperature TС = 1048 ± 5 K: \(\gamma {\kern 1pt} '\) = 0.51 and γ = 0.35, which in absolute value significantly exceed the value of the characteristic critical index for the heat capacity (γ ≈ –0.1). The thermal conductivity (λ) is calculated from measured data of the thermal diffusivity. The results are compared with the known literature data, special attention is paid to the behavior of the curves a(T), λ(T) in the region of the magnetic phase transformation. A table of recommended temperature dependences for a and λ along with estimated errors has been developed.
Ieffect of Ultrasonic Impact Treatment on the Microstructure and Fatigue Life of 3D-Printed Titanium Alloy Ti–6Al–4V
Authors: Perevalova O. B. , Panin A. V. , Kazachenok M. S. , Martynov S. A.
Published: April 2024

Abstract—Using a hard alloy (Co–WC) striker, ultrasonic impact treatment (UTT) of Ti–6Al–4V alloy samples obtained by electron-beam wire additive technology was carried out. Using X-ray diffraction analysis and transmission electron microscopy, it has been shown that UTT leads to the appearance of compressive macrostresses in the surface layers of the sample, elastic microdeformation in the crystal lattice of the alpha-phase, to the formation of a gradient structure from nanocrystalline at a depth of 5 μm to a submicrocrystalline structure of the alpha-phase at a depth from 15 to 40 microns.A nanocrystalline phase of titanium oxides is formed in the grains of the alpha phase. UTT leads to an increase in microhardness and fatigue life. A fractographic analysis of specimen fractures after cyclic tension in the low-cycle fatigue regime has been carried out.
Magnetocalorical Effect and Phase Separation: Theory and Perspectives
Authors: Igoshev P. A.
Published: April 2024

Abstract—The problem of the magnetic phase separation effect on the magnitude of the magnetocaloric effect is considered. A general thermodynamic generalized Landau theory with a variable particle number is proposed, which allows simple and consistent treatment of the first order phase transition between the magnetically ordered and disordered phases, taking into account the phase separation. The calculation of the magnetic susceptibility and entropy of phases involved in the phase separation was considered. It is shown that the magnetic susceptibility of the magnetically ordered (disordered) phase participating in the phase separation is negative (positive) in the vicinity of the tricritic point, which can result in the inversion of the sign of the magnetocaloric effect.
Effect of Ga Partial Substitution on the Structural and Magnetic Properties of Heusler Ni–Mn–Ga Alloys
Authors: Sokolovskiy V. V. , Buchelnikov V. D.
Published: April 2024

Abstract—The effect of doping with Cu and Zn atoms on the magnetic and structural properties of the cubic and tetragonal phase of the Heusler Ni2Mn1.125Ga0.875 alloy has been investigated in the framework of density functional theory. Partial substitution of Ga atoms by Cu and Zn atoms leads to a decrease in the energy difference between the ferromagnetic and ferrimagnetic states of the cubic phase and an increase in the energy barrier between the cubic and tetragonal phase. The latter observation indirectly points to the increase in the structural transition temperature observed experimentally. Within the framework of calculations of exchange interaction parameters from first principles and Monte Carlo modeling of temperature dependences of magnetization, a phase T–x diagram is constructed. It is shown that the Curie temperature of the tetragonal phase decreases significantly compared to the Curie temperature of the cubic phase with increasing Cu and Zn content due to an increase in the inter-sublattice antiferromagnetic interaction between Mn atoms.
Magnetostriction and Magnetocaloric Properties of the Mn1 – xFexAs System
Authors: Gadzhiev A. B. , Gamzatov A. G. , Khanov L. N. , Mityuk V. I. , Govor G. A. , Aliev A. M.
Published: April 2024

Abstract—The results of studying the temperature dependence of the magnetocaloric effect (ΔТad), thermal expansion and magnetostriction in the Mn1 – хFexAs (х = 0.003, 0.006) system in magnetic fields up to 8 T are presented. It is shown that an increase in the iron concentration in the Mn1 – xFexAs system leads to a shift in the phase transition temperature towards low temperatures by 15 K. In a field of 8 T, the value ΔTad = 8.3 K for the Mn0.997Fe0.003As sample at the initial temperature T0 = 318 K, and ΔTad = 7.7 K for Mn0.994Fe0.006As at T0 = 307 K. The data on thermal expansion and magnetostriction show that the magnetostriction decreases with increasing iron concentration, which also leads to a decrease in the magnetocaloric effect.
THE INFLUENCE OF STRUCTURAL AND COMPOSITIONAL FACTORS ON THE REALIZATION OF THE EXCHANGE BIAS EFFECT IN (Cr-Mn)/Fe20Ni80
Authors: Feshchenko A. A. , Moskalev M. E. , Severova S. V. , Gorkovenko A. N. , Lepalovskij V. N. , Selezneva N. V. , Kravtsov E. A. , Vas'kovskiy V. O.
Published: April 2024

The influence of a number of physical factors on the structural and hysteresis properties of multilayer films (Cr-Mn)/Fe Ni has been studied. By indirect signs, the presence of antiferromagnetism in Cr-Mn layers with a Mn content in the range of 20-40 at.% has been established. It is shown that in such structures, the exchange bias effect can be observed, but only when the thickness of the antiferromagnetic layer is greater than 40 nm. The initial reason for the low "fixing" properties of the Cr-Mn layer is its weak magnetic anisotropy, which is superimposed with instability in the reproduction of the micro-structure. The use of substrate heating during film deposition increased the reproducibility of microstructure parameters and hysteresis characteristics but led to a weakening of the exchange bias effect, apparently due to changes in the structure and composition of the interlayer interface.
Structural Investigations and Rheology of Convergence of Thick-Wall Shells from Al–Mg Alloy
Authors: Brodova I. G. , Shirinkina I. G. , Astafiev V. V. , Balushkin S. V. , Kulikov G. V. , Simonov A. Y.
Published: April 2024

Abstract—The deformation behavior of thick-walled hollow cylindrical shells made of the AMg6 alloy (Al–6.1% Mg–0.6% Mn–0.1% Ti–0.2% Si, wt %) loaded according to an 8-point initiation scheme of an attached explosive is considered. The intensity of explosive loading was regulated by the amount of explosives. It has been established that, different scenarios for their convergence are observed depending on the intensity of the impact and the geometric characteristics of the shells. The conditions for the formation of spallation internal layers were determined, the evolution of the structure during high-speed deformation along the radius and along the length of the shells and the change in hardness along the radius of the shells were studied. X-ray photography of the dynamics of shell deformation processes was carried out at different time intervals. The speeds of movement of the outer and inner layers of the shells and the speed of their deformation for different amounts of explosives were determined.
Model for Prediction of the Size of Austenite Grains Upon Hot Deformation of Low-Alloyed Steels Taking into Account the Evolution of the Dislocation Structure
Authors: Gorbachev I. I. , Korzunova E. I. , Popov V. V. , Khabibulin D. M. , Urtsev N. V.
Published: April 2024

Abstract—A model is proposed to describe the behavior of the average size of austenite grains and the dislocation structure of low-alloyed steels during and after hot deformation. The model takes into account the processes of recovery, dynamic recrystallization of grains and normal grain growth, as well as the strain-induced precipitation of carbonitride phases and their evolution. The calculation results are compared with the experimental data available in the literature and their satisfactory agreement is shown.
Formation a Layered Dissipative Structure in the Process of Directed Growth of an MgB2 Crystal from a Melt
Authors: Esin V. O.
Published: April 2024

Abstract—The interaction of components during high-temperature annealing of pressed magnesium and boron powders during the production of the superconducting compound MgB2 is considered in works using standard synthesis technology and hot gas-static pressing technology. In a computer model of crystallization of a binary alloy, the influence of the diffusion of components in the region of the interphase boundary during crystal growth on the morphology of dissipative structures formed during phase transformation was studied. An analysis of the conditions and mechanism of the formation of a “layered” structure that appears during the crystallization of MgB2 from a magnesium melt in the (Mg–B) system has been carried out.
Modern Magnetocaloric Materials: Existing Problems and Research Prospects
Authors: Sokolovskiy V. V. , Zagrebin M. A. , Buchelnikov V. D. , Marchenkov V. V.
Published: April 2024

Abstract—
A brief review of works related to a new and promising direction – magnetic cooling technology based on the magnetocaloric effect (MCE) is presented. The essence of the effect and the main publications related to this area are briefly considered. The materials in which the MCE is observed are reported and the corresponding diagrams of the main publications on the MCE for the last 5 years are presented. The latest results of research by Russian scientists working in this field are presented.
Trans-Factor PTF1 Participates in the Response to Salinity but Does Not Regulate Expression of the psbD Gene in Arabidopsis thaliana
Authors: Andreeva A. A. , Bychkov I. A. , Kudryakova N. V. , Kuznetsov V. V.
Published: April 2024

The existing data on the role of PTF1/TCP13 belonging to the TCP family of transcription factors in regulating expression of a psbD plastid gene encoding a D2 protein of PSII are controversial. To analyze biological functions of PTF1/TCP13, transformed plants expressing PTF1/TCP13 under a -estradiolinducible promoter were used. PTF1/TCP13 overexpression did not provide the expected increase in the accumulation of psbD transcripts transcribed from BLRP (Blue Light Responsive Promoter), though their level significantly increased under exposure to light or abscisic acid (ABA). PTF1/TCP13 was up-regulated by ABA; moreover, genes of the canonic pathway of the ABA signal transduction were involved in the regulation of PTF1/TCP13 expression. In addition, PTF1/TCP13 was induced in response to salt stress However, in the overexpressing line, salt tolerance and expression of salt stress markers, as well as a number of genes for the synthesis and signaling of ABA, were reduced compared to plants with the normal level of expression of this transcription factor, that is, PTF1/TCP13 acted as a negative regulator of salt stress Thus, PTF1 does not belong to plastid transcription factors. Nevertheless, it represents one of the components of the ABA-dependent regulatory chain capable of modifying expression of nuclear and chloroplast genes in response to changes in homeostasis.
Anthocyanin Content in the Capsicum Species Fruits Correlates with Expression Levels of Flavonoid Pathway Structural and Regulatory Genes
Authors: Filyushin M. A. , Shchennikova A. V. , Kochieva E. Z.
Published: April 2024

In fruits of cultivars of pepper species Capsicum annuum (Sirenevyi Cub), C. frutescens (Samotsvet) and C. chinense (Pimenta da Neyde), which differ in the pigmentation profile during maturation, the content of anthocyanins and the expression pattern of the structural and regulatory genes of anthocyanin biosynthesis were determined. Anthocyanins were found in the fruit of the Sirenevyi Cub cultivar as well as in the peel and pulp of Samotsvet and Pimenta da Neyde cultivars. In the peel of the fruits of all three analyzed cultivars, the levels of expression of structural genes for the biosynthesis of anthocyanins are two or more times higher than in the pulp. In cv. Samotsvet and Pimenta da Neyde, the expression in the pulp of CHS, F35H, DFR, ANS, and UFGT are higher than that of cv. Sirenevyi Cub. The cv. Pimenta da Neyde is characterized by a high expression of structural genes in the pulp and peel of ripe fruit. Expression of transcription factor genes anthocyanin2 (R2R3-MYB) and MYC (bHLH) was detected in the peel of fruits of cv. Sirenevyi Cub as well as in the peel and pulp of fruits of cv. Samotsvet and Pimenta da Neyde at all the analyzed stages of ripening. For all structural genes of the anthocyanin biosynthesis pathway, a high correlation was found (r = 0.54‒0.93) between the expression levels of all anthocyanin biosynthesis structural genes and anthocyanin content in fruits. High correlation (r = 0.88) is also shown for MYC. For the anthocyanin2, correlation (r = 0.85) is present only for cv. Sirenevyi Cub and Pimenta da Neyde but not for cv. Samotsvet.
Regulation of Pro-/Antioxidant Balance in Higher Plants by Nanoparticles of Metals and Metal Oxides
Authors: Venzhik Yu. V. , Deryabin A. N.
Published: April 2024

A comparative analysis of available data suggests that metal and metal oxide nanoparticles widely used in plant physiology participate in the regulation of pro-/antioxidant balance in higher plants. The dual role of nanoparticles is shown: on the one hand, they act as triggers of oxidative stress and, on the other hand, they can counteract stress development and improve the efficiency of the plants antioxidant system. Under abiotic stress conditions, nanoparticles can act as adaptogens, thus enhancing the antioxidant defense of plants. Possible mechanisms of nanoparticle action, as well as the prospects for their application in fundamental science and agriculture are discussed.
The role of methylation of glutamate dehydrogenase gene promoters (GDH1 and GDH2) in the regulation of their expression in corn leaves under hypoxia
Authors: Eprintsev A. T. , Anokhina G. B.
Published: April 2024

The regulation of glutamate dehydrogenase, an enzyme that is involved in both nitrogen and carbon metabolism, and also links between the tricarboxylic acid cycle and the -aminobutyric acid shunt, has been studied. It was found that oxygen deficiency-induced changes in glutamate dehydrogenase activity in maize leaves (Zea mays L.) are to increase its catalytic activity by more than twice. Differential expression of genes was studied by real-time PCR in GDH1 and GDH2, which encode the - and -subunits of glutamate dehydrogenase, respectively, in the maize genome. Decreased relative level of gene transcripts GDH2 was accompanied by an increase in the expression activity of the gene GDH1. This, in turn, presumably promoted the amination reaction of 2-oxoglutarate. In the promoter of the gene GDH2, the presence of two CpG islands 404 and 383 bp in size was found. Gene promoter GDH1 does not contain a single CpG island; however, 38% of the CpNpG and CpNpN sites of the total number of studied dinucleotides in its composition were found. To assess the influence of the degree of methylation of individual CpG dinucleotides that are part of the promoter regions of genes GDH1 and GDH2 on their expression under hypoxic conditions, a comparative analysis of the dynamics of the transcriptional activity of the genes of - and -subunits of glutamate dehydrogenase from the methyl status of their promoters was carried out. Inversely proportional superposition of changes in the methylation profile of gene promoters GDH1 and GDH2 and transformation of the level of expression of these genes shows their correlation. The data obtained as a result of methyl-specific PCR indicate that an increase in the proportion of methylated CpG dinucleotides leads to a decrease in the amount of mRNA of the gene GDH2, while a decrease in this value for the gene GDH1 causes the induction of its functioning. Methylation of promoter regions of glutamate dehydrogenase genes regulates their transcriptional activity in maize leaves in vivo under conditions of oxygen deficiency. Thus, the little data on the molecular mechanisms of regulation of the synthesis of glutamate dehydrogenase isoenzymes were supplemented by new results on the role of the degree of methylation of gene promoters GDH1 and GDH2 glutamate dehydrogenases in their differential expression during maizes adaptation to hypoxia.
Biochemical composition of Euglena gracilis cells during mixotrophic growth in the presence of various organic substrates
Authors: Gulk E. I. , Zamyatkina E. B. , Birkemeyer C. , Tarakhovskaya E. R.
Published: April 2024

The general biochemical composition and profile of low molecular weight metabolites of euglena (Euglena gracilis Klebs.) cells grown in a mixotrophic culture supplemented with 0.5% ethanol, glucose, butanol, glycine, or glycerol was studied. Ethanol and glucose significantly stimulated the growth of the Euglena culture and the accumulation of storage compounds (paramylon and wax esters) in the cells. Butanol also contributed to the division of euglena cells and increased biosynthesis of protein, mono- and disaccharides, carotenoids, and tocopherols. Glycine and glycerol were metabolized more slowly than other substrates, and they accumulated in E. gracilis cells along with their direct derivatives. Glycine did not stimulate the growth of the culture, but it caused the accumulation of paramylon, organic acids of the Krebs cycle, and nitrogen-containing metabolites (chlorophyll, free amino acids, and nitrogenous bases) in the cells. Apparently, glycine is equally effectively used by Euglena as an additional source of both carbon and nitrogen under the conditions of mixotrophy. Assimilation of glycerol was accompanied by the accumulation of wax esters and the amino acids proline and ornithine in Euglena cells. In general, the results obtained demonstrate the ability of Euglena to significantly rearrange its metabolism during the assimilation of organic substrates of various chemical nature. Our data can be used in the context of E. gracilis practical applications.
Early Blight Resistance of Transgenic Potato Plants Expressingthe ProSmAMP1 Gene for Antimicrobial Peptides under the Control of a Light-Inducible Cab Promoter
Authors: Beliaev D. V. , Yourieva N. O. , Tereshonok D. V. , Derevyagina M. K. , Meleshin A. A.
Published: April 2024

The genome of Stellaria media contains a gene family for hevein-like antimicrobial peptides, some of which are known to encode two peptides released from the translation product as a result of post-translational proteolysis. These peptides have been shown to inhibit the growth of bacteria and fungi, including potato pathogens Alternaria solani and Alternaria alternata. One of these genes, ProSmAMP1, was introduced into the potato genome under the control of the light-inducible promoter of Cab gene from common wheat. The resulting transgenic lines expressed ProSmAMP1 mRNA during several vegetative passages, and their resistance to early blight was assessed by several indicators of detached leaf infection, with plants having the highest expression of the transgene also showing the highest resistance.
Coexpression of Structural and Regulatory Genes of the Flavonoid Pathway Reveals the Characteristics of Anthocyanin Biosynthesis in Eggplant Organs (Solanum melongena L.)
Authors: Filyushin M. A. , Shchennikova A. V. , Kochieva E. Z.
Published: April 2024

Eggplant (Solanum melongena L.) is an economically important vegetable crop whose purple-colored fruits are enriched with anthocyanidins. In this work in the eggplant genome, homologues of the main known structural (CHS1, CHS2, CHI, F3H, F35H, DFR, ANS, and UFGT) and regulatory (TT8, GL3, bHLH137, bHLH143, MYB1, MYB2, and MYB75) anthocyanin biosynthesis genes, as well as anthocyanidin transporter gene (GSTF12), were identified. The expression of these genes was characterized in comparisonwith the content of the total anthocyanins and the color of the leaf, flower petals, and fruit peel. It was shown that the gene expression pattern corresponds to the color and the presence of anthocyanins in the tissue, and also indicates the presence of organ-specific characteristics of the regulation of transcription of genes encoding transcription factors of the MBW complex. The results of correlation analysis confirm the involvement of SmbHLH137, SmTT8, SmMYB2, and SmMYB75 genes in the regulation of the expression of structural genes in flower petals and SmGL3, SmTT8, and SmMYB1 in fruit peel.