Defect formation in two-dimensional nanostructures based on carbon under ion irradiation
Defect formation in two-dimensional nanostructures based on carbon under ion irradiation
Yu. V. Balakshin$^1$, D. K. Minnebaev$^{1,2}$, O. M. Marchenko$^{1,3}$, A. D. Shporin$^{1,2}$
In this work, the influence of incident particles energy transferred to the target atoms on the destruction of a graphene coating deposited on copper foil was studied. The graphene coating was irradiated using He$^+$ and Ar$^+$ ions at an energy of 100 keV at room temperature of the sample. The study of the target structure before and after irradiation was carried out by the method of Raman scattering of light. The simulation of energy loss by incident ions during interaction with target atoms was carried out by the Monte Carlo method in the approximation of binary collisions. It was shown that the main mechanism of destruction of the graphene coating during irradiation is the elastic interaction of the incident particles with the target atoms.
Show AbstractIon-beam surface treatment of PDMS to improve cell adhesion
Ion-beam surface treatment of PDMS to improve cell adhesion
O. M. Marchenko$^2$, A. P. Yakovlev$^3$, D. K. Minnebaev$^{1,2}$, D. S. Kireev$^{1,2}$, Yu. V. Balakshin$^2$, A. V. Nazarov$^{1,2}$, A. D. Shporin$^{1,2}$
The object of the study were samples of pure polydimethylsiloxane (hereinafter PDMS) and cells of the HEK-293 cell line. Experiments were carried out to modify the PDMS surface with beams of atomic and cluster argon ions with energies of 10 keV. Ion beams were directed at angles of $60^\circ$ and $90^\circ$ to the surface of the samples, the radiation fluence ranged from $10^{15}$ to $10^{16}$~ions/cm$^2$. The modified surface was studied by atomic force and optical microscopy methods. The study of cell adhesion was carried out by scanning ion-conducting and optical microscopy. As a result of the study, improving of the conditions for cell adhesion on the surface of PDMS during pretreatment of this surface with a beam of atomic argon ions was demonstrated, and the formation of the microrelief during ion irradiation on the surface of the samples was observed.
Show AbstractModeling of the setup for carbon analysis of soil samples
Modeling of the setup for carbon analysis of soil samples
A. V. Andreev$^1$, N. A. Fedorov$^2$
The paper presents the results of modeling the installation for neutron activation analysis of soils with different carbon concentrations. The simulation was carried out using the GEANT4 package. The values of the trigger threshold are obtained and the possibility of applying the considered configuration of the installation for practical use is discussed.
Show AbstractInvestigation of electrostatic discharges during irradiation of elements of thermal control coatings of spacecraft radiators
Investigation of electrostatic discharges during irradiation of elements of thermal control coatings of spacecraft radiators
V. A. BASOV
This study analyzes the characteristics of electrostatic discharges occurring on the surface of K-208 glasses irradiated in a vacuum of $10^{-4}$~Pa by electrons with an energy of 40 keV at a particle flux density of $3\cdot 10^{10}$~cm$^{-2}$~s$^{-1}$ and varying the fluences from $10^{14}$ to $10^{16}$~cm$^{-2}$. Discharges of type 1 and type 2 with plasma ejection into the surrounding space were observed when the glasses were irradiated. The frequency of discharges increased and the amplitude of discharge currents decreased when the fluences were varied from $10^{14}$ to $10^{16}$~cm$^{-2}$. This is explained by the increase of glass electric conductivity caused by the change of stoichiometry and structure of the material during discharges. Along with electrostatic discharges, there are also breakdowns on the irradiated surface of the sample to the metal subsurface material of glass K-208. Under certain conditions, these processes may stimulate each other, that is, an electrostatic discharge may provoke a breakdown and vice versa.
Show AbstractDegradation of ECOM-1 material under electron irradiation
Degradation of ECOM-1 material under electron irradiation
A. M. Shamaev
The impact of ionizing radiation from outer space on the materials of the outer surfaces of spacecraft (SC) leads to the degradation of their functional properties. In particular, polymer composite materials used as a thermoregulatory coating for spacecraft are subjected to high dose loads. The article investigates the changes in the spectral reflectance of samples of the ECOM-1 material as a result of a series of four stages of irradiation in vacuum with electrons with energies of 40 keV and exposure of the samples between the next radiation exposure in room conditions. EKOM-1 is a composite material based on an acrylic copolymer filled with ZnO particles, and therefore one of the channels for its degradation, especially when irradiated with medium-energy particles, is the radiation-stimulated decomposition of the ZnO molecule. To interpret the experimental results, an elementary model of accumulation and annealing of radiation defects is presented. In the elementary model proposed below, it is postulated that the rate of change in the defect concentration $n(х,t)$ is proportional to the normalized energy release function $S_{normal}(x)$ in the ECOM-1 sample under electron irradiation. The calculation results, which demonstrate the nature of the change in the concentration of color centers during irradiation, showed that the concentration of defects with the time of irradiation reaches a certain level of saturation, which depends on the intensity of irradiation. This is due to the fact that during irradiation, along with the formation of defects, their annihilation occurs, for example, due to interaction with electrons thermalized in the material. The presented model requires its development, and at present can only serve to illustrate the process of accumulation of defects in the irradiated material.
Show AbstractSemi-empirical relations for the half-lives of superheavy elements
Semi-empirical relations for the half-lives of superheavy elements
D. F. Bayramov, T. Yu. Tretyakova
We considered phenomenological equations for the half-lives of superheavy elements through alpha decay and spontaneous fission channels predictions. Based on modern experimental data, new values of the fitting parameters were obtained and predictions of the full half-life and half-life periods were made by using spontaneous fission and alpha decay channels for Fm ($Z = 100$) and No ($Z=102$) isotopes.
Show AbstractElliptical and triangular flows of charged particles in relativistic collisions of Xe and Pb nucleus in the HYDJET++ model and experiment CMS (LHC)
Elliptical and triangular flows of charged particles in relativistic collisions of Xe and Pb nucleus in the HYDJET++ model and experiment CMS (LHC)
D. A. Miagkov$^1$, S. -. Petrushanko$^2$
This paper describes the simulation of particle production in Pb--Pb and Xe--Xe collisions at the energies of the Large Hadron Collider (LHC) using the HYDJET++ Monte Carlo generator. The distributions of elliptical $v_{2}$ and triangular $v_{3}$ flows of charged particles in two types of collisions are studied. The results of the HYDJET++ generator simulation are qualitatively compared with the experimental data of the Compact Muon Solenoid (CMS) detector.
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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