First principles calculations of the physical properties of orthorhombic HfxA1-xO2 (A = Zr, Ti)
First principles calculations of the physical properties of orthorhombic HfxA1-xO2 (A = Zr, Ti)
A. A. Reznik$^{1,2,3}$, A. A. Rezvanov$^{1,2}$, V. S. Konstantinov$^{1,2}$
The paper evaluates the structural, electrophysical and mechanical properties of IV-B dioxides and the HfxA1-xO2 compound (A = Zr, Ti) by the density functional theory method in the Quantum ESPRESSO software package. It is established that orthorhombic TiO2 titanium dioxide does not exhibit ferroelectric properties, has a narrow band gap and a high value of dielectric permittivity compared with orthorhombic hafnium and zirconium dioxides. The introduction of zirconium atoms into the hafnium dioxide unit cell does not cause significant changes in the structure, leads to a decrease in the band gap and an increase in residual polarization. Compounds of the type HfxZr1-xO2 (x = 0.25, 0.5) have a high value of the elastic modulus, compared with stoichiometric HfO2 and ZrO2.
Show AbstractPhotoelectric properties of nanofibers of composites based on cobalt oxide with zinc
Photoelectric properties of nanofibers of composites based on cobalt oxide with zinc
V. V. Smirnova$^1$, M. N. Martyshov$^1$, A. S. Ilin$^{1,3}$, V. B. Platonov$^2$, P. A. Forsh$^{1,3}$, P. K. Kashkarov$^{1,4}$
In this work, the photoelectric properties of Co3O4/Zn composites with different contents of zinc atoms in the range from 0 to 33 mole percent by cation (mol%) were studied. The composites were obtained by electrospinning and consisted of nanofibers 150–200 nm in diameter with a nanocrystalline structure. The possibility of increasing the dark conductivity and photoconductivity of Co3O4/Zn composites by adding zinc atoms to the structure has been demonstrated. It has been found that the kinetics of the rise and fall of photoconductivity when samples are illuminated with ultraviolet radiation can be approximated by the sum of two exponentials. This indicates the existence of two different processes that determine the recombination of nonequilibrium charge carriers in the material. It is shown that one of these processes can be associated with the adsorption and desorption of molecules on the surface of nanofibers. The ability to carry out adsorption and desorption due to illumination of Co3O4/Zn composites makes them promising for use in gas sensors.
Show AbstractElliptical and triangular azimuthal particle flows in Xe–Xe and Pb–Pb collisions with the Monte Carlo model HYDJET++ and the CMS experiment at the LHC (CERN)
Elliptical and triangular azimuthal particle flows in Xe–Xe and Pb–Pb collisions with the Monte Carlo model HYDJET++ and the CMS experiment at the LHC (CERN)
D. A. Miagkov$^1$, S. V. Petrushanko$^2$
Monte Carlo generator HYDJET++ was used to study the azimuthal anisotropy of particles produced in Xe–Xe collisions at an energy of \sqrt{s_{NN}} = 5.44 TeV and Pb–Pb at an energy of 5.02 TeV per nucleon pair in the center mass frame. Obtained results are compared with the experimental data of the Compact Muon Solenoid (CMS) at the Large Hadron Collider (LHC) in European Council for Nuclear Research (CERN).
Show AbstractRaman Spectroscopy of Aqueous Suspensions of Zinc Sulfide (ZnS) Nanoparticles
Raman Spectroscopy of Aqueous Suspensions of Zinc Sulfide (ZnS) Nanoparticles
R. R. Volkov$^1$, I. V. Plastinin$^1$
In this work, the methods of Raman spectroscopy, dynamic light scattering (DLS), and absorption spectroscopy in the ultraviolet region were used to study aqueous solutions in which the synthesis of ZnS nanoparticles was carried out by co-precipitation. It was found that more than 99% of the synthesized nanoparticles were 41 ± 3 nm in size, and aqueous suspensions of ZnS nanoparticles had an absorption band in the region of 315 nm. As a result of studying the processes in the reaction medium by Raman spectroscopy, it was found that the band of stretching vibrations of HS - ions in the region with a maximum of 2572 cm-1 is an identification sign of the synthesis of nanoparticles: it is possible to determine the stage and completion of the synthesis of ZnS nanoparticles by its intensity. The results obtained make it possible to develop a non-contact and express method for diagnosing the reaction medium during the synthesis of nanoparticles in them.
Show AbstractGeneration of long waves during the movement of a submarine landslide body and wave resistance force
Generation of long waves during the movement of a submarine landslide body and wave resistance force
M. V. Lebkov
Within the framework of the linear theory of long waves, on the basis of an accurate analytical solution of a one-dimensional problem, the features of the generation of gravitational surface waves during the movement of a non-deformable landslide body are investigated. Explicit expressions describing the energy of the waves, as well as the strength of the wave resistance, are obtained. It is established that the pumping of energy to the waves, and, consequently, the action of the wave resistance force, is limited in time. It is shown that the calculation of the wave resistance force by the instantaneous parameters of the body motion is impossible due to the fact that the magnitude of this force is determined by the prehistory of the movement of the landslide body. Estimates of the magnitude of the wave resistance force suggest that it can be comparable to the forces of "dry" and turbulent friction.
Show AbstractMir-IR femtosecond laser pulses wavefront reconstruction using machine learning methods
Mir-IR femtosecond laser pulses wavefront reconstruction using machine learning methods
N. Y. Victorovich$^1$, A. V. Mitrofanov$^{2,3,4}$, M. V. Rozhko$^{1,3}$, N. G. Iroshnikov$^1$, D. A. Sidorov-Biryukov$^{1,3,4}$
The paper shows the possibility of using convolutional neural networks for a laser beam wavefront reconstruction by measuring the intensity distribution in the transverse plane at some distance behind the focusing system. The optimal distance from the focusing system to the measurement plane is determined at which the error for the rms devation of Zernike polynomials amplitudes decreases sharply. A neural network has been trained on a computer-generated samples of beams with various types of aberrations to reconstruct the wavefront of real beams in the presence of noise
Show AbstractStudy of petroleum paraffin and resins by NMR relaxation
Study of petroleum paraffin and resins by NMR relaxation
T. .. Kazbayev, D. S. Ivanov
Due to the complexity of the chemical and molecular composition of oil, it is usually used to identify four main components: asphaltenes, resins, paraffins and oils. According to the accepted methods of GOST 11851085, M 01-12-81 paraffins are extracted not directly from oil as, for example, asphaltenes, but from pre-separated oils. In this study, results of research by NMR of benzene and alcohol-benzene resins extracted from oil according to the standardized procedure of GOST 11858-66 were carried out. It was found that benzene resins show hysteresis in NMR characteristics that is typical of systems with the first order phase transition, while alcoholtobenzene resins show no hysteresis over the temperature range from minus 80 to plus 65 degrees Celsius accurate to the experimental error. It has been suggested that as a result of peculiarities of interaction between resins and paraffins, the paraffins are extracted from oil mainly in the composition of benzene resins.
Show AbstractImprovement of TalysLib library
Improvement of TalysLib library
G. V. Pampushik$^1$, N. A. Fedorov$^2$
This work describes the main features of TalysLib library. The addition of a functionality to TalysLib for automatically obtaining experimental information from EXFOR is discussed. Several approaches to automating the acquisition of experimental data have been tested.
Show AbstractMass relations for unknown atomic nuclei mass predictions
Mass relations for unknown atomic nuclei mass predictions
T. Yu. Tretyakova$^{1,2}$, A. P. Ivleva$^2$
On the basis of the AME2020 data we consider the mass relations such as $\Delta_{np}$, $\delta V_{np}$ and Harvey-Kelson relations that are associated with neutron-proton correlations and can be used to predict masses of unknown atomic nuclei. The behavior of these characteristics is analyzed within the framework of the liquid drop model and in the Hartree-Fock microscopic approach in comparison with modern experimental data. New approximations of $\Delta_{np}$ and $\delta V_{np}$ as functions of the mass number $A$ are obtained.
Show AbstractDirected propagation of the scalar potential of Pocchammer-Chree waves in auxetics: projection operators method
Directed propagation of the scalar potential of Pocchammer-Chree waves in auxetics: projection operators method
D. V. Ampilogov, M. A. Dmitrieva
We investigate the problem of propagation of scalar potential of Pocchammer-Chree waves in cylindrical auxetic. The approximated equation of evolution of are built by means of projection operators method. The general solution for left and right waves is obtained.
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