|№||Мақала атауы||Авторлары||Жылы||Журнал атауы||Қысқаша аннотация|
|1||Melting, freezing, and dynamics of two-dimensional dipole systems in screening bulk media||Aldakul, Y.K., Moldabekov, Z.A., Ramazanov, T.S||2020||Physical Review E, Volume 102, Issue 3, September 2020, Article number 033205, Q1.
|This paper reports on the molecular dynamics simulations of classical two-dimensional (2D) electric dipole systems. The properties of 2D systems with bare (nonscreened) and screened dipole-dipole interactions have been investigated. Based on the polygon construction method, we present simulation results on the phase transition, and we locate the melting and freezing points of 2D dipole systems in terms of a polygon disorder parameter, with the polygon disorder parameter being the sum of nontriangular polygon order parameters. It was found that the phase transition of the system occurs when the polygon disorder parameter has a value 0.165. This result was cross-checked by using both local and overall orientational order parameters. We also identified that the value of the average local orientational order parameter at the phase transition point is 0.67. These results are valid for the ordinary (bare) dipole-dipole interaction as well as the screened dipole-dipole interaction, and they are expected to be general for other 2D systems with repulsive pair interaction. We observed that both melting and freezing points shift to lower values of temperature due to screening. In the liquid state, the radial distribution function and polygon construction method show the loss of order in a structure as screening becomes more severe. Furthermore, the impact of screening on the system's collective excitation spectra and diffusive characteristics at liquid and solid states has been studied. Results show the decrease in the values of both longitudinal and transverse sound speeds and the emergence of anomalous superdiffusive motion in the liquid state due to screening.|
|2||Synthesis of carbon nanowalls on the surface of nanoporous alumina membranes by RI-PECVD method||Yerlanuly, Y., Christy, D., Van Nong, N., Kondo, H., Alpysbayeva, B., Nemkayeva, R., Kadyr, M., Ramazanov, T., Gabdullin, M., Batryshev, D., Hori, M||2020||Applied Surface Science, Volume 5231, September 2020, Article number 146533, Q1.
|This work is devoted to the synthesis of carbon nanowalls on the surface of a nanoporous aluminum oxide membrane by radical-injection plasma enhanced chemical vapor deposition method. Nanoporous alumina oxide membranes with different morphology and thickness, which were obtained by the method of two-stage electrochemical anodization, were used as a substrate. For comparative analysis, carbon nanowalls were also obtained on the surface of a silicon substrate and aluminum foil. The synthesized nanostructures were investigated by using scanning electron microscopy and Raman spectroscopy. The dependence of the morphology and height of carbon nanowalls on the pore size and the thickness of the alumina membrane, respectively, was revealed.|
|3||Thermodynamics and statistical physics of quasiparticles within the quark-gluon plasma model||Dzhunushaliev, V., Folomeev, V., Ramazanov, T., Kozhamkulov, T.||2020||Modern Physics Letter A, Open access, Volume 35, Issue 23,July 30, 2020, Article number 2050194, Q2.
|We consider thermodynamic properties of a quark-gluon plasma related to quasiparticles having the internal structure. For this purpose, we employ a possible analogy between quantum chromodynamics and non-Abelian Proca-Dirac-Higgs theory. The influence of characteristic sizes of the quasiparticles on such thermodynamic properties of the quark-gluon plasma like the internal energy and pressure is studied. Sizes of the quasiparticles are taken into account in the spirit of the van der Waals equation but we take into consideration that the quasiparticles have different sizes, and the average value of these sizes depends on temperature. It is shown that this results in a change in the internal energy and pressure of the quark-gluon plasma. Also, we show that, when the temperature increases, the average value of characteristic sizes of the quasiparticles increases as well. This leads to the occurrence of a phase transition at the temperature at which the volume occupied by the quasiparticles is compared with the volume occupied by the plasma.|
|5||Superhydrophobic carbonous surfaces production by PECVD methods||Orazbayev, S., Zhumadilov, R., Zhunisbekov, A., Gabdullin, M., Yerlanuly, Y., Utegenov, A., Ramazanov, T.||2020||Applied Surface Science, Volume 515, June 15, 2020, Article number 146050, Q1.
|The paper presents the results of a complex study of superhydrophobic surfaces obtained by PECVD methods in RF discharge plasma with gas mixtures (Ar/CH4 and Ar/C2H2) and by plasma jet (Ar/CH4). In both experiments hydrophobic surfaces were obtained by deposition of carbon nanoparticles on glass and silicon substrates by plasma of Ar (93%) + CH4 (7%) and Ar (93%) + C2H2 (7%) gas mixtures. To compare surfaces with high hydrophobicity produced by the above two methods their contact angles were studied. The dependence of changes in the contact angle on the storage time of the samples under normal conditions show that samples obtained in Ar/CH4 plasma and plasma jet at atmospheric pressure are much better preserved.|
|6||Ion energy-loss characteristics and friction in a free-electron gas at warm dense matter and nonideal dense plasma conditions||Moldabekov, Z.A., Dornheim, T., Bonitz, M., Ramazanov, T.S.||2020||Physical Review E, Open access, Volume 101, Issue 5, May 2020, Article number 053203, Q1.
|We investigate the energy-loss characteristics of an ion in warm dense matter (WDM) and dense plasmas concentrating on the influence of electronic correlations. The basis for our analysis is a recently developed ab initio quantum Monte Carlo- (QMC) based machine learning representation of the static local field correction (LFC) [Dornheim, J. Chem. Phys. 151, 194104 (2019)JCPSA60021-960610.1063/1.5123013], which provides an accurate description of the dynamical density response function of the electron gas at the considered parameters. We focus on the polarization-induced stopping power due to free electrons, the friction function, and the straggling rate. In addition, we compute the friction coefficient which constitutes a key quantity for the adequate Langevin dynamics simulation of ions. Considering typical experimental WDM parameters with partially degenerate electrons, we find that the friction coefficient is of the order of γ/ωpi=0.01, where ωpi is the ionic plasma frequency. This analysis is performed by comparing QMC-based data to results from the random-phase approximation (RPA), the Mermin dielectric function, and the Singwi-Tosi-Land-Sjölander (STLS) approximation. It is revealed that the widely used relaxation time approximation (Mermin dielectric function) has severe limitations regarding the description of the energy loss of ions in a correlated partially degenerate electrons gas. Moreover, by comparing QMC-based data with the results obtained using STLS, we find that the ion energy-loss properties are not sensitive to the inaccuracy of the static local field correction (LFC) at large wave numbers, k/kF>2 (with kF being the Fermi wave number), but that a correct description of the static LFC at k/kF1.5 is important.|
|7||Destruction of a dust particle in the white dwarf atmosphere||Kenzhebekova, A.I., Bastykova, N.K., Kodanova, S.K., Ramazanov, T.S., Maiorov, S.A., Moldabekov, Z.A.||2020||Japanese Journal of Applied Physics, Volume 59, Issue SH, May 1, 2020, Article number SHHA04, Q2.
|Dusty white dwarfs are natural objects for studying the properties of cosmic dusty plasmas. We present the results of computation of the charge, radius, and temperature of a carbon dust particle in the atmosphere of dusty white dwarf G29-38, which is a typical example of a dusty white dwarf. The calculation results show that dust particles life-time in the atmospheres of dusty white dwarfs is of the order of microsecond. Therefore, dust particles cannot be sustained in a typical white dwarf atmosphere.|
|8||Particle formation during deposition of SiO x nanostructured thin films by atmospheric pressure plasma jet||Ussenov, Y.A., Hansen, L., Krüger, T., Ramazanov, T.S., Kersten, H.||2020||Japanese Journal of Applied Physics, Volume 59, Issue SH, May 1, 2020, Article number SHHE06, Q2.
|In this work, the results of SiO x thin film deposition by an atmospheric pressure plasma jet using HMDSO (hexamethyldisiloxane) as precursor are presented. The experiments were performed for different process parameters like initial applied power, substrate to nozzle distance and speed of the moving substrate holder. In order to determine the properties of deposited films the samples were analyzed by scanning electron microscopy, transmission electron microscopy, atomic force microscopy and profilometer. The formation mechanism of particles and their size distribution depending on the process parameters are described and discussed. The results show the possibility to change properties of deposited films and particle formation by tuning the experimental settings.|
|9||Subdiffusion of dust particles in cryogenic plasmas||Aldakulov, Y.Q., Moldabekov, Z.A., Muratov, M., Ramazanov, T.S.||2020||Japanese Journal of Applied Physics, Volume 59, Issue SH,May 1, 2020, Article number SHHE02, Q2.
|Neutral shadowing force, which becomes comparable with a screened Coulomb force at extreme cryogenic conditions, can significantly change the properties of complex plasmas. In this work, the impact of neutral shadowing force on the mean square displacement (MSD) of dust particles is investigated. This is done by performing Langevin dynamics simulations of a 2D system of strongly correlated particles. The results of this work show that the additional force due to the neutral shadowing effect has a strong impact on MSD, i.e. the diffusive motion of particles, only if the mean free path of neutral gas particles exceeds the mean inter-dust-particle distance. In the latter case, we find that neutral shadowing force leads to subdiffusion on time scales of the order of tens or hundreds of dust particle plasma oscillation periods. Furthermore, we find that neutral shadowing force can strongly hinder the transition from anomalous diffusion to normal diffusion.|
|10||Dense plasmas with partially degenerate semiclassical ions: Screening and structural properties||Ismagambetova, T.N., Moldabekov, Z.A., Amirov, S.M., Ramazanov, T.S., Gabdullin, M.T., Temirbek, A., Tikhonov, A.||2020||Japanese Journal of Applied Physics, Volume 59, May 1, 2020, Article number SHHA10, Q2.
|The screened interaction potential between ions taking into account the wave nature of ions is presented. The parameters considered in this paper correspond to those of dense plasmas with ideal or weakly coupled quantum electrons and semiclassical non-ideal ions. The wave nature of ions is described using the concept of quantum potentials. The obtained effective interaction potential between ions takes into account screening by electrons and ionic quantum nonlocality. It is shown that the polarization of electrons around an ion leads to a decrease in the ion's effective thermal wavelength and, conversely, screening of the ion field by electrons becomes weaker due to the wave nature of the ion. Furthermore, on the basis of the derived ion-ion interaction potential, we investigate the structural properties of semiclassical non-ideal ions. For hydrogen plasmas, the ionic quantum nonlocality effect is significant at r S < 0.3. The obtained results are relevant to high energy density physics.|
|11||Collision between a charged particle and a polarizable neutral particle in plasmas||Bastykova, N.K., Moldabekov, Z.A., Kodanova, S.K., Ramazanov, T.S||2020||Physics of Plasmas, Volume 27, Issue 4, April 1, 2020, Article number 044502, Q2.
|The collision of a polarizable neutral particle with a charged particle in plasmas is studied. The neutral particle interaction with a charged particle is considered to be due to an induced dipole moment. Taking into account screening and a finite size of colliding particles, we present accurate and simple interpolation formulas for the total scattering cross section in the case of contact of the neutral particle with the dust particle surface. The results are obtained for both weak and strong coupling between colliding particles.|
|12||Obtaining of carbon nanowalls in the plasma of radio-frequency discharge||Batryshev, D., Yerlanuly, Y., Alpysbaeva, B., Nemkaeva, R., Ramazanov, T., Gabdullin, M.||2020||Applied Surface Science, Volume 503, February 15, 2020, Article number 144119, Q1.
|In this work a synthesis of carbon nanowalls (CNWs) in the plasma of argon and methane gases of capacitively coupled radio-frequency (CCRF) discharge is considered. The carbon nanowalls were synthesized by plasma enhanced chemical vapor deposition method at relatively lower values of discharge power and gas flow rate for low-cost CNWs production. The growth process of carbon nanowalls was studied at different synthesis parameters. The morphology and structure quality of obtained samples were investigated by Raman spectroscopy, scanning electron and atomic force microscopies. It was found, that at a lower value of RF power the formation of CNWs goes better with increasing methane flow rate and further increasing RF power leads to agglomeration of nanowalls and formation of nanoclusters, which then transfer into multilayered graphene. Thus, on the basis of obtained results, a process map with different zones of deposited carbon nanostructures is developed.|
|13||Dynamic characteristics of three-dimensional strongly coupled plasmas||Arkhipov, Y.V., Ashikbayeva, A., Askaruly, A., Davletov, A.E., Dubovtsev, D.Y., Santybayev, K.S., Syzganbayeva, S.A., Conde, L., Tkachenko, I.M.||2020||Physical Review E, Volume 102, Issue 5, November 30, 2020, Article number 053215, Q1.
|The dynamic structure factor and other dynamic characteristics of strongly coupled one-component plasmas have been studied [Yu. V. Arkhipov, Phys. Rev. Lett. 119, 045001 (2017)PRLTAO0031-900710.1103/PhysRevLett.119.045001] using the self-consistent version of the method of moments. Within any version of the latter, the system dielectric function satisfies all involved sum rules and other exact relations automatically, and the advantage of this version is that, in addition, the dynamic characteristics (the dynamic structure factor, the dispersion, and decay parameters of the collective modes) are all expressed in terms of the static ones (the static structure factor) without any adjustment to the simulation data. The approach outlined in the aforementioned Letter is justified in detail and applied mainly to the classical Coulomb systems achieving satisfactory agreement with new numerical simulation data. It is shown how the realm of applicability of the method can be extended to partly degenerate and multicomponent systems, even to simple liquids. Some additional theoretical results are presented in the Supplemental Material.|
|14||Performance optimization of back-contact perovskite solar cells with quasi-interdigitated electrodes||Shalenov, E.O., Dzhumagulova, K.N., Ng, A., Jumabekov, A.N.||2020||Solar Energy, Volume 205, Pages 102 - 108, July 15, 2020, Q1.
|A numerical simulation method is used to investigate intricacies of a complex relation between the back-contact electrode (BCE) geometric parameters, the perovskite photo-absorber layer electronic properties, and device performance in back-contact perovskite solar cells (BC-PSCs) with quasi-interdigitated electrodes (QIDEs). To unlock the full potential of BC-PSC with QIDEs, the device performance was investigated by systematically varying the geometric parameters of BCE and the perovskite photo-absorber layer electronic parameters in order to determine the conditions for a best device performance. BC-PSC with QIDEs have a potential to produce power conversion efficiencies (PCEs) higher than PSCs with the conventional sandwich architecture if optimized parameters for electrode geometry and perovskite electronic properties are used. The findings of the present work give an insight into the work principle of these devices and provide a theoretical guidance for design and fabrication of high-performance BC-PSC with QIDEs.|
|15||The pulse vacuum-arc plasma generator for nanoengineering application||Zhukeshov, A.M., Gabdullina, A.T., Amrenova, A.U., Fermakhan, K.||2020||Applied Physics A: Materials Science and Processing, Volume 126, Issue 91, September 2020, Article number 742, Q2.
|In paper described the results of work on the application of vacuum-arc machine in nanoengineering area. Researches were carried out to optimize the operation of this machine for the synthesis of nanomaterials in low-pressure arc-discharge plasma, plasma diagnosis and production of nanopowders. An electrode system based on the grounded cathode with impulse ignition has been developed. The anode current was measured and the mass output of the product was calculated. Experimental data on energy density were obtained, confirming the presence of plasma focusing on the electrode system axis due to its own magnetic field, the focus value of which reaches about 18 kJ/m2. Powder samples were also obtained in the form of clusters containing the copper particles (up to 98%) and spherical powder with size from 116 nm to 1.2 µm. Homogeneity and dispersion of powder depended on the time of the processes accompanying the deposition.|
|16||Plasma-grain interaction in ultracold complex plasmas||Sundar S., Moldabekov Z.A.||2020||Physics of Plasmas, Volume 27, Issue 3, March 1, 2020, Article number 033701, Q2.
|The present particle-in-cell simulation for grain-plasma interaction at cryogenic temperatures springs from recent experimental realization of ultracold dusty plasmas with atoms and ions at superfluid helium temperatures. In this work, we discuss the results of particle-in-cell simulations (taking into account ion-atom collisions) for dust particle charge, ion drag force, and interaction between grains in ultracold dusty plasmas. The single grain as well as two grain system is investigated, considering both streaming ions and equilibrium ions. The dependence of plasma mediated inter-grain interactions on the streaming velocity of ions and inter-particle separation is delineated in detail. Additionally, ion density distribution around grains is discussed. The interactions at cryogenic temperatures are distinct from those at room temperature by their differences in magnitude and interaction mechanism details. Most remarkable features are (i) the inter-grain attraction in equilibrium plasmas due to plasma absorption on the surface of grains, (ii) the ion drag force directed against ion streaming velocity in the case of a single dust particle, and (iii) non-linear response of the plasma polarization around grains with an increase in the streaming velocity of ions.|
|17||Ultracold ions wake in dusty plasmas||Sundar S., Moldabekov Z.A.||2020||New Journal of Physics, Open access, Volume 22, Issue 3, March 2020, Article number 033028, Q1.
|Motivated by the recent experimental realization of ultracold dusty plasma (2019 Sci. Rep. 9 3261), we present the results of particle-in-cell simulation with Monte-Carlo-collisions for wake behind a dust particle due to focusing of ions at superfluid helium temperature (2 K). Dynamical screening (wakefield) defines structural and dynamical properties of charged dust particles in plasmas such as phase transition, crystal formation, vibration modes (waves) etc. Here, we delineate in detail the dependence of wake strength on the streaming velocity of ions and on the ion-neutral charge exchange collision frequency (neutrals density) in the ultracold dusty plasma. Lowering the temperature to ultracold level leads to a wake pattern behind a dust particle that completely differs from the wake at normal conditions. For wide range of parameters, most remarkable features of the wakefield are (i) the formation of wake pattern with two maxima split in transverse to ion flow direction in the downstream area, (ii) pronounced inverse V shape of the wakefield closely resembling the wake in quark-gluon plasma and dense quantum plasma (warm dense matter), and (iii) the inter-dust attraction region in transverse direction. The latter shows that molecule-like interaction between dust particles is realized in ultracold dusty plasmas. These observations show a fundamental difference of ultracold dusty plasma physics from well studied complex plasmas at normal conditions.|
|18||Oblique magnetic field influence on the wakefield in complex plasmas||Sundar S., Moldabekov Z.A.||2020||Plasma Physics and Controlled Fusion, Volume 62, Issue 10, October 2020, Article number 105018, Q1.
|The results of an investigation of the wakefield around a stationary charged grain in an external magnetic field with non-zero transverse component with respect to the ion flow direction is presented. In contrast to the previously reported significant suppression of the wake oscillations due to the magnetic field applied along the flow, the wake potential exhibits long range recurrent oscillations in the presence a of transverse flow to the magnetic field. Extensive analysis for a wide range of parameters elucidate a strong dependence of the wake on the orientation of the magnetic field in the sonic and supersonic regimes by manifesting sensitivity to even a meager deviation of magnetic field from the longitudinal direction. The impact of the orientation and strength of magnetic field on the wake behavior is assessed. The deviation of the magnetic field induction vector from the longitudinal to ion flux direction leads to the wakefield with two positive peaks split in the transverse to ion flow direction in the downstream region; similar to that of the ultracold ions wake without magnetic field [(2020) New J. Phys. 22 033028].|
|19||International ENTER project: A new pedagogical training approach for engineering educators||Shageeva, F.T., Mishchenko, E.S., Chernyshov, N.G., Nurgalieva, K.E., Turekhanova, K.M., Omirzhanov, Y.T.||2020||Vysshee Obrazovanie v Rossii, Open access, Volume 29, Issue 6, Pages 65 - 742020, Q2.
|The formation of a modern generation of engineers capable to drive changes that meet the requirements of the future necessitates a new approach in pedagogical training of engineering teachers. The international ENTER (EngineeriNg educaTors pEdagogical tRaining) project is being developed as part of EU Erasmus program focused on addressing the actual education needs from the standpoint of human and social capitals development both in Europe and in other countries. The ENTER project is aimed at the creation and development of an international platform for multilevel vocational training/retraining of technical universities teachers on the basis of the Eurasian interaction network. Surveys among employers, teachers, and engineering university students, as well as scientific periodicals analysis allowed us to determine the complex of universal and specific engineering and pedagogical competencies that educators should master not only for today, but also for the future needs. Based on the competency analysis, a three-level modular teacher training/retraining program (iPET program) has been developed and its international accreditation is planned.|