East European Journal of Physics 2022-07-31T14:02:21+00:00 Serhii Hirnyk Open Journal Systems <p>EEJP is an international peer-reviewed journal devoted to experimental and theoretical research on nuclear physics, cosmic rays and particles, high-energy physics, solid-state physics, plasma physics and controlled thermonuclear fusion, physics of charged particle beams, plasma electronics, radiation materials science, physics of thin films, condensed matter physics, functional materials and coatings, technical thermal physics and industrial power, medical physics and physical technologies in an interdisciplinary context.</p> <p>EEJP registered by the order of Ministry of Education and Science of Ukraine <strong>No. 1643 of 28.12.2019</strong>, and included in the list of scientific professional Editions of Ukraine (<strong>category “A”, specialty: 104, 105</strong>), in which results of dissertations for obtaining Ph.D. and Dr. Sci. degrees in physical and mathematical sciences can be published.</p> <p>The Journal is a part of the <strong>Web of Science Core Collection (ESCI)&nbsp;</strong>scientometric platform and indexed by&nbsp;<strong>SCOPUS</strong>.</p> <p><a title="SCImago Journal &amp; Country Rank" href=";tip=sid&amp;exact=no"><img src="" alt="SCImago Journal &amp; Country Rank" border="0"></a>&nbsp;</p> <p>&nbsp;</p> Influence of the Inert Gas Pressure on Intrinsic Stress in Diamond-Like Coating Deposited From Vacuum Arc Carbon Plasma 2022-06-02T18:20:41+00:00 Alexandr I. Kalinichenko Vladimir E. Strel’nitskij <p>Within the framework of the model of the nonlocal thermoelastic peak of low-energy ion, the formation of intrinsic stress in a carbon coating deposited from the vacuum arc plasma in the argon atmosphere is theoretically studied. It is shown that the flow of particles bombarding the deposited coating contains, along with C<sup>+</sup> ions, also Ar<sup>+</sup> ions involved in the formation of intrinsic stress in the coating. The flux density of Ar<sup>+</sup> ions resulting from ionization losses of C<sup>+</sup> ions passing through the argon atmosphere is proportional to both the flux density of C<sup>+</sup> ions and the density (pressure) of argon. Expressions are obtained for the intrinsic stress in the deposited carbon coating depending on the bias potential on the substrate and the argon pressure for the cases of both constant and pulsed potentials. The analysis of the obtained expressions shows that the intrinsic stress in the carbon coating decrease with increasing argon pressure.</p> 2022-06-02T00:00:00+00:00 Copyright (c) 2022 Alexandr I. Kalinichenko, Vladimir E. Strel’nitskij Solutions of the Schrödinger equation with Hulthén-screened Kratzer potential: Application to Diatomic Molecules 2022-06-02T18:20:42+00:00 Etido Inyang P.C. Iwuji Joseph E. Ntibi E.S. William E.A. Ibanga <p>In this study, the Schrödinger equation with the Hulthén plus screened Kratzer potentials (HSKP) are solved via the Nikiforov-Uvarov (NU) and the series expansion methods. We obtained the energy equation and the wave function in closed form with Greene-Aldrich approximation via the NU method. The series expansion method was also used to obtain the energy equation of HSKP. Three distinct cases were obtained from the combined potentials. The energy eigenvalues of HSKP for HCl, LiH, H<sub>2</sub>, and NO diatomic molecules were computed for various quantum states. To test the accuracy of our results, we computed the bound states energy of HCl and LiH, for a special case of Kratzer and screened Kratzer potentials, which are in excellent agreement with the report of other researchers.</p> 2022-06-02T00:00:00+00:00 Copyright (c) 2022 Etido Inyang, P.C. Iwuji, Joseph E. Ntibi, E.S. William, E.A. Ibanga General Analysis of the Reaction e^+ + e^- → N + Ñ + π^0 2022-06-02T18:20:39+00:00 Gennadiy I. Gakh Mykhailo I. Konchatnij Nikolay P. Merenkov Egle Tomasi-Gustafsson <p>The general analysis of the reaction , in the case of longitudinally polarized electron beam, has been performed in the one-photon-nnihilation approximation, accounting for the polarization states of the final nucleon. This analysis is useful for the description of the continuum (non-resonant) and resonant (with different possible vector mesons or excited baryons in the intermediate virtual states of the Feynman diagrams) contributions. The conservation of the hadron electromagnetic currents and P-invariance of the hadron electromagnetic interaction were used to express the matrix element in terms of the six complex independent invariant amplitudes. The general structure of the hadronic tensor for the case of unpolarized final hadrons and polarized nucleon has been derived. The spin-independent part of the hadronic tensor is determined by five structure functions and the spin-dependent one by 13 structure functions. The transversal, longitudinal and normal components of the nucleon polarization four-vector are expressed by means of the four-vectors of the particle momenta. The five independent invariant variables which describe the reaction have been introduced. The limits of the changing of these variables have been considered. The kinematical double invariant variables regions are given in the figure. The kinematics, suitable to study the invariant mass distributions, is investigated.</p> 2022-06-02T00:00:00+00:00 Copyright (c) 2022 Gennadiy I. Gakh, Mykhailo I. Konchatnij, Nikolay P. Merenkov, Egle Tomasi-Gustafsson Specific Features of the Simulation of the Particle Diffusion Processes in Spatially Periodic Fields 2022-06-02T18:20:39+00:00 Viktoriia Yu. Аksenova Ivan G. Marchenko Igor I. Marchenko <p>This paper is devoted to the studies of the specific features of the simulation of the particle diffusion processes in space – periodic potentials using Langevin equations. Different methods used for the presetting of initial conditions and their effect on the obtained solutions have been analyzed. It is shown that the system is nonequilibrium for all the methods of the presetting of initial conditions during a certain time interval of <em>t<sub>trm</sub></em>. This interval is increased as 1/γ with a decrease in the friction coefficient. A reasonable description of the transient processes of particle transport and diffusion requires a preliminary system thermalization procedure. A new method of the presetting of initial conditions that provides the most accurate description of equilibrium system has been suggested. It consists in the generation of the initial particle coordinates and velocities that correspond to the equilibrium distribution of harmonic oscillators with a specified temperature. The use of such initial conditions enables the computations with a good accuracy using no thermalization procedure at T &lt; 0.1. The classic method of the determination of diffusion coefficients D as a limit lim<sub>t→ꝏ</sub>&nbsp;(σ<sup>2</sup>/t) has been analyzed. It was shown that the use of it for computer-aided calculations is limited by the restricted computational time. It results in that the computation of D under certain conditions becomes impossible. A new method was suggested for the determination of the diffusion coefficient using the linear approximation of the dependence of dispersion on time. This approximation can only be possible after the kinetic temperature attains its stationary value. The suggested method requires several orders of magnitude less time in comparison to the classic method. As a result, it enables the computation of the diffusion coefficient even in the cases of total previous failure. The obtained data are of great importance for correct simulation computations of diffusion processes and for the appropriate physical interpretations of obtained data.</p> 2022-06-02T00:00:00+00:00 Copyright (c) 2022 Viktoriia Yu. Аksenova, Ivan G. Marchenko, Igor I. Marchenko Quark-Antiquark Study with Inversely Quadratic Yukawa Potential Using the Nikiforov-Uvarov-Functional-Analysis Method 2022-06-02T18:20:38+00:00 Etido P. Inyang Prince C. Iwuji Joseph E. Ntibi E. Omugbe Efiong A. Ibanga Eddy S. William <p>The solutions of the Schrödinger equation are obtained with an inversely quadratic Yukawa potential using the Nikiforov-Uvarov-Functional-analysis method. The energy spectrum and wave function were obtained in closed form. The energy equation was used to predict the masses of the heavy mesons such as charmonium (<em>сĉ</em>) and bottomonium (<em>bḃ</em>) for different quantum numbers. The results obtained agreed with other theoretical predictions and experimental data with a percentage error of 1.68 % and 0.50 % for charmonium (<em>сĉ</em>) and bottomonium (<em>bḃ</em>) respectively.</p> 2022-06-02T00:00:00+00:00 Copyright (c) 2022 Etido P. Inyang, Prince C. Iwuji, Joseph E. Ntibi, E. Omugbe, Efiong A. Ibanga, Eddy S. William A Numerical Simulation for Efficiency Enhancement of CZTS Based Thin Film Solar Cell Using SCAPS-1D 2022-06-02T18:20:42+00:00 Muhammad Aamir Shafi Sumayya Bibi Muhammad Muneeb Khan Haroon Sikandar Faisal Javed Hanif Ullah Laiq Khan Bernabe Mari <p>In this paper we proposed a solar cell having model “<em>Back Contact/CZTS/ZnCdS/ZnO/Front Contact</em>”. CZTS is working as an absorber layer, ZnCdS as a buffer layer and ZnO as a window layer with back and front contacts. The Zn content was varied from 0% to 10% and bad gap was changed from 2.42 to 2.90 eV as described in the literature. The impact of this band gap variation has been observed on the performance of solar cell by using SCAPS-1D software. The efficiency was varied due to variation in bandgap of ZnCdS thin film layer. The simulation was carried out at 300K under A.M 1.5 G 1 Sun illumination. The energy bandgap diagram has been taken from SCAPS to explain the different parameters of solar cell. The effect of ZnCdS having different bandgap values was observed. Then the thickness of CZTS layer was varied to check its effect and hence at 3.0 um gave the imporved efficiency of 13.83% roundabout. After optimization of CZTS layer thickness, the effect of working temperature was examined on the performance of solar cell. The absorption coefficient variation from 1E+4 to 1E+9 cm<sup>-1</sup> caused major effects on the characteristics parameters of solar cell along with on J-V characteristics and Quantum Efficiency curve. At 1E+9 cm<sup>-1</sup> absorption coefficient the efficiency of solar cell boost up to 16.24%. This is the remarkable improvement in the efficiency of solar cell from 13.82% to 16.24%. After optimization of all parameters, simulation was run at 280K, having CZTS thickness of 3.5 um, with 10% content Zn in ZnCdS (2.90 eV), and absoption coefficient of 1E+9, the model efficiency reached up to&nbsp; 17.6% with Voc of 0.994 V, Jsc 26.1 mA/cm<sup>2</sup> and Fill factor was 71.4%.</p> 2022-06-02T00:00:00+00:00 Copyright (c) 2022 Muhammad Aamir Shafi, Sumayya Bibi, Muhammad Muneeb Khan, Haroon Sikandar, Faisal Javed, Hanif Ullah, Laiq Khan, Bernabe Mari Effect of Parasitic Parameters and Environmental Conditions on I-V and P-V Characteristics of 1D5P Model Solar PV Cell Using LTSPICE-IV 2022-06-02T18:20:41+00:00 Muhammad Aamir Shafi Muneeb Khan Sumayya Bibi Muhammad Yasir Shafi Noreena Rabbani Hanif Ullah Laiq Khan Bernabe Mari <p>In this research work, the electrical simulation of 1D5P model solar cell is done using LTSpice-IV simulation software. In this work effect of environmental conditions i.e temperature, solar irradiance, and parasitic parameters i.e series as well as shunt resistances was carried out. It has been discovered that as temperature increases the performance of solar cell decrease because temperature causes to increase the recombination phenomenon and hence lower the performance. However, when the temperature rises from 0<sup>0</sup>C to 50<sup>0</sup>C, the I-V and P-V curves move to the origin showing the negative effect of increasing temperature on the solar cell. Solar irradiance has major role on the performance of solar cell. As solar irradiance increases from 250 Wm<sup>-2</sup> to 1000 Wm<sup>-2</sup>, the performance of solar cell increases accordingly and I-V as well as P-V curve moves away from the origin. It is concluded that for different series resistances, I-V along with P-V characteristic of 1D5P model solar cell varies, as at 0.02Ω series resistance, a maximum short circuit current and maximum power is obtained. But when series resistance increased up 2 ohm only, the I-V and P-V curves moves to origin drastically. Shunt Resistance is the path of reverse current of the cell. As the shunt resistance increases, the path for reverse current decreased, hence all current goes to load, hence maximum power is obtained. Similarly when the value of shunt resistance decreased, the voltage-controlled section of I-V characteristics curve is moved closer to the origin hence reduced the solar cell performance. It's critical to understand how different factors affect the I-V and P-V characteristics curves of solar cells. The open circuit voltage, short circuit current and maximum power is all variable. The influence of these factors may be extremely beneficial when tracking highest power point of a solar cell applying various methods.</p> 2022-06-02T00:00:00+00:00 Copyright (c) 2022 Muhammad Aamir Shafi, Muneeb Khan, Sumayya Bibi, Muhammad Yasir Shafi, Noreena Rabbani, Hanif Ullah, Laiq Khan, Bernabe Mari Boron Isotopic Ratio (δ11B) Measurements in Boron Carbide (B4C): Benchmarking Between SF-ICP-MS and PIGE Techniques 2022-06-02T18:20:41+00:00 Dmytro Kutnii Stanislav Vanzha Dmytro Burdeynyi Volodymyr Levenets O. Omelnik A. Shchur <p>The results of comparing the analytical capabilities of Sector Field Inductively Coupled Plasma Mass Spectrometry (SF-ICP-MS) and Particle Induced Gamma-ray Emission (PIGE) methods for determining the <sup>11</sup>B/<sup>10</sup>B isotope ratio in boron carbide samples (B<sub>4</sub>C) are presented. The following nuclear reactions excited by protons on the stable boron isotopes are considered: <sup>10</sup>B(p,aγ)<sup>7</sup>Be, <sup>10</sup>B(p,pγ)<sup>7</sup>Be and <sup>11</sup>B(p,γ)<sup>12</sup>C. The optimum proton energy range was determined to be within 550 to 600&nbsp;keV, while the energies of the induced gamma-radiation that can be used for quantitative estimation of the boron isotopes were 429&nbsp;keV and 4439&nbsp;keV for the isotopes <sup>10</sup>B and <sup>11</sup>B, respectively. Considering the uncertainties of measurements, the data for the <sup>11</sup>B/<sup>10</sup>B&nbsp;isotope ratios, measured by the SF‑ICP‑MS and PIGE methods, are found to correlate with each other; yet they are characterized by a systematic bias. The uncertainty of measurements by the PIGE method was somewhat higher in comparison with SF-ICP-MS, and ranged from ±&nbsp;4.1&nbsp;% to ±&nbsp;4.3&nbsp;%, and from ±&nbsp;1.1&nbsp;% to ±&nbsp;3.5&nbsp;%, respectively.</p> 2022-06-02T00:00:00+00:00 Copyright (c) 2022 Dmytro Kutnii, Stanislav Vanzha, Dmytro Burdeynyi, Volodymyr Levenets, O. Omelnik, A. Shchur Study of Electrical Properties of Nano TiO2 Coatings Based on the Characteristic Matrix Theory and the Brus Model 2022-06-02T18:20:40+00:00 Sarah A. Hijab Saeed N. Turki Al-Rashid <p>Electrical properties of Nano TiO<sub>2</sub> coatings as a function of the nanoparticle size have been studied. In addition, this study explores how to calculate the quantum confinement energy of TiO<sub>2</sub>. The results confirm the effect of particle size on electrical properties especially when the size becomes close to the exciton Bohr radius. The electrical properties are not effected when the size becomes close to 40 nm. The Bohr radius of Nano TiO<sub>2</sub> coatings has been found to be 1.4 nm. While the confinement energy was 0.43 eV. The program depends on the Characteristic Matrix Theory and The Brus Model.</p> 2022-06-02T00:00:00+00:00 Copyright (c) 2022 Sarah A. Hijab, Saeed N. Turki Al-Rashid Investigation of a Glow Discharge with a Coaxial Hollow Cathode 2022-07-31T14:02:21+00:00 Stanislav V. Pogorelov SVPOG@YAHOO.CO.UK Ihor V. Krasovskyi Volodymyr A. Timaniuk Nikolay G. Kokodii <p>The article is devoted to the study of the operating modes of a glow discharge with a coaxial hollow cathode in helium and neon gases. It is shown that the burning voltage of a discharge with a coaxial hollow cathode is lower than one with a cylindrical hollow cathode of equal diameter, and the position of the optimal pressure range depends on the width of the annular gap of the cavity. It is noted that the rod current density is 3-5 times higher than the cylinder current density. The insignificant role of the photoelectric effect in the processes of electron emission from the cathode is proved. It is shown that the intensity of the atomic spectral lines of the cathode material increases significantly when a coaxial hollow cathode is used.</p> 2022-06-02T00:00:00+00:00 Copyright (c) 2022 Stanislav V. Pogorelov, Ihor V. Krasovskyi, Volodymyr A. Timaniuk, Nikolay G. Kokodii Effects of Different Factors on the Heat Conduction Properties of Carbon Films and Fibers 2022-06-02T18:20:40+00:00 Junjie Chen <p>The increasing popularity of carbon nanotubes has created a demand for greater scientific understanding of the characteristics of thermal transport in nanostructured materials. However, the effects of impurities, misalignments, and structure factors on the thermal conductivity of carbon nanotube films and fibers are still poorly understood. Carbon nanotube films and fibers were produced, and the parallel thermal conductance technique was employed to determine the thermal conductivity. The effects of carbon nanotube structure, purity, and alignment on the thermal conductivity of carbon films and fibers were investigated to understand the characteristics of thermal transport in the nanostructured material. The importance of bulk density and cross-sectional area was determined experimentally. The results indicated that the prepared carbon nanotube films and fibers are very efficient at conducting heat. The structure, purity, and alignment of carbon nanotubes play a fundamentally important role in determining the heat conduction properties of carbon films and fibers. Single-walled carbon nanotube films and fibers generally have high thermal conductivity. The presence of non-carbonaceous impurities degrades the thermal performance due to the low degree of bundle contact. The thermal conductivity may present power law dependence with temperature. The specific thermal conductivity decreases with increasing bulk density. At room temperature, a maximum specific thermal conductivity is obtained but Umklapp scattering occurs. The specific thermal conductivity of carbon nanotube fibers is significantly higher than that of carbon nanotube films due to the increased degree of bundle alignment.</p> 2022-06-02T00:00:00+00:00 Copyright (c) 2022 Junjie Chen The Features of Intense Electron Flow Impact on Metal Hydride Electrode 2022-06-02T18:20:40+00:00 Ihor Sereda Yaroslav Hrechko Ievgeniia Babenko Mykola Azarenkov <p>The features of generation of a shielding plasma layer by a Zr<sub>50</sub>V<sub>50</sub> metal hydride surface which prevents the sample from melting have been studied. The sample was interacting with an electron beam formed directly by the metal hydride. The electron beam was emitted from primary plasma generated by an additional discharge with a filament cathode and accelerated in the space charge layer at the front of the shielding plasma, which is formed on hydrogen desorbed from metal hydride or on the sample material in case of the depletion of stored hydrogen. Three different stages of the formation of shielding plasma layer have been identified depending on the ratio between the current to the metal hydride <em>I<sub>MH</sub></em> and the current of the primary plasma source <em>I<sub>d</sub></em>. When <em>I<sub>MH</sub>/I<sub>d</sub>&nbsp;&lt;&nbsp;1</em> the classical conditions for charged particles transfer are realized. At <em>I<sub>MH</sub>/I<sub>d</sub>&nbsp;&gt;&nbsp;1</em> the classical conditions for the transfer of charged particles are violated and double layer appears at the front of the shielding plasma, which ensures the efficient energy transfer from external electrical field to the energy of bipolar motion of charged particles.</p> 2022-06-02T00:00:00+00:00 Copyright (c) 2022 Ihor Sereda, Yaroslav Hrechko, Ievgeniia Babenko, Mykola Azarenkov Structural, Thermal, and Electronic Investigation of ZrCo1-xNixBi (x=0, 0.25, 0.75, and 1) Half-Heusler Alloys 2022-06-02T18:20:39+00:00 Mahmoud Al-Elaimi <p>This article presents the theoretical evaluation of the structural, mechanical, thermal and electrical properties of half-Heusler &nbsp;(ZrCo<sub>1-x</sub>Ni<sub>x</sub>Bi &nbsp;= 0, 0.25, 0.75 and 1) alloys in the framework of density functional theory (DFT) that is implemented in WIEN2k code. Equilibrium lattice parameters are found agree with previous literature. Several calculated mechanical properties are revealed that all studied alloys are mechanically stable. According to the critical values for B/G, Ni-doped ZrCoBi alloys are ductile, whereas ZrCoBi&nbsp;and ZrNiBi are brittle. The band structure and density of states of the present compounds show that ZrCoBi has a semiconducting nature, while Ni-doped ZrCoBi&nbsp;has a half-metallic nature. The structural reforms, brought to ZrCoBi as the Ni-dopant concentration increases at the site of Co-atom, showed an increase in its metallicity, conductivity and ductility, and a decrease in its rigidity, stiffness, minimum thermal conductivity, melting and Debye temperatures. According to the results obtained, &nbsp;( ZrCo<sub>1-x</sub>Ni<sub>x</sub>Bi&nbsp;= 0, 0.25, 0.75 and 1) alloys could have potential thermal and electronic applications.</p> 2022-06-02T00:00:00+00:00 Copyright (c) 2022 Mahmoud Al-Elaimi Correlating Deposition Parameters with Structure and Properties of Nanoscale Multilayer (TiSi)N/CrN Coatings 2022-06-02T18:20:38+00:00 Vyacheslav M. Beresnev Olga V. Maksakova Serhiy V. Lytovchenko Serhiy A. Klymenko Denis V. Horokh Andrey S. Manohin Bohdan O. Mazilin Volodymyr O. Chyshkala Vyacheslav A. Stolbovoy <p>Multilayer (TiSi)N/CrN coatings were fabricated through vacuum-arc deposition by applying the arc currents of (100 ÷ 110) A on TiSi cathode and (80 ÷ 90) A on Cr cathode, negative bias potential connected to the substrate holder of –(100 ÷ 200) V and reactive gas pressure of (0.03 ÷ 0.6) Pa. Applying a negative bias voltage on substrates enhanced the ion bombardment effect, which affected the chemical compositions, phase state, mechanical and tribological properties of (TiSi)N/CrN coatings. Obtained results indicated that (TiSi)N/CrN coatings with Si content ranging from 0.53 to 1.02 at. % exhibited a high hardness level of (22.1 ÷ 31.1) GPa accompanied with a high Young’s modulus of (209 ÷ 305) GPa, H/E* level of (0.080 ÷ 0.100), H<sup>3</sup>/E*<sup>2</sup> level of (0.15 ÷ 0.33) GPa, and the friction coefficient of 0.35. Values of critical loads at dynamic indentation, changes in friction coefficient and level of acoustic emission signal evidence the high adhesive strength of (TiSi)N/CrN coatings, which allows recommending them to increase cutting tool performance.</p> 2022-06-02T00:00:00+00:00 Copyright (c) 2022 Vyacheslav M. Beresnev, Serhiy V. Lytovchenko, Serhiy A. Klymenko, Denis V. Horokh, Аndrey S. Manohin, Bohdan O. Mazilin, Volodymyr O. Chyshkala, Vyacheslav A. Stolbovoy Comparison of Numerically Simulated and Measured Dose Rates for Gamma-Irradiation Facility 2022-06-02T18:20:37+00:00 Volodymyr Morgunov Imre Madar Serhii Lytovchenko Volodymyr Chyshkala Bohdan Mazilin <p>The article provides a description of steps which were made to make comparison between numerically simulated and measured dose rates in Izotop gamma-irradiation facility (Budapest, Hungary) Numerical simulation was carried out with the help of software toolkit GEANT4. Dose measurement were made by ethanol-chlorobenzene (ECB) dosimeters. The comparison shows a good agreement between simulated and measured values. Worst accuracy was 17.08%.</p> 2022-06-02T00:00:00+00:00 Copyright (c) 2022 Volodymyr Morgunov, Imre Madar, Serhii Lytovchenko, Volodymyr Chyshkala, Bohdan Mazilin Interaction of Novel Monomethine Cyanine Dyes with Proteins in Native and Amyloid States 2022-06-02T18:20:36+00:00 Olga Zhytniakivska Uliana Tarabara Atanas Kurutos Kateryna Vus Valeriya Trusova Galyna Gorbenko <p>Molecular interactions between novel monomethine cyanine dyes and non-fibrilar and fibrilar proteins were assessed using fluorescence spectroscopy and molecular docking techniques. To this end, the fluorescence spectral properties of dyes have been explored in the buffer solution and in the presence of insulin and lysozyme in the native and amyloid states. It was observed that association of monomethines with the native and fibrillar proteins was accompanied with a significant enhancement of the fluorophore fluorescence, being more pronounced in the presence of aggregated insulin and lysozyme. The quantitative information about the dye-protein binding was obtained through approximating the experimental dependencies of the fluorescence intensity increase <em>vs </em>protein concentration by the Langmuir model. Analysis of the spectral properties and the binding characteristics of monomethines in the presence of the fibrillar insulin and lysozyme showed that the introduction of chloro- and fluorine-substitutients to the oxazole yellow derivatives, as well as the long aliphatic substitution on the nitrogen atom of the benzazole chromophore of YO-dyes had a negative impact on the dye amyloid specificity. Molecular docking studies showed that monomethines tend to form the most stable complexes with the B-chain residues Val 17, Leu17, Ala 14, Phe1, Gln 4 and Leu 6 and the A-chain residue Leu 13, Tyr 14, Glu 17 of non-fibrilar insulin and interact with the deep cleft of native lysozyme lined with both hydrophobic (Ile98, Ile 58, Thr108, Thr 62 and Thr 63 residues) and negatively (Asp101, Asp 107) charged residues. The wet surface groove Gln15_Glu17 and groove G2-L4/S8-W10 were found as the most energetically favorable binding sites for examined monomethine dyes in the presence of the insulin and lysozyme fibrils, respectively<strong>.</strong></p> 2022-06-02T00:00:00+00:00 Copyright (c) 2022 O. Zhytniakivska, U. Tarabara, A. Kurutos, K. Vus, V. Trusova, G. Gorbenko Interactions of Fibrillar Insulin with Proteins: A Molecular Docking Study 2022-06-02T18:20:35+00:00 Valeriya Trusova Olga Zhytniakivska Uliana Tarabara Kateryna Vus Galyna orbenko <p>During the last decades growing attention has been paid to ascertaining the factors responsible for the toxic potential of particular protein aggregates, amyloid fibrils, whose formation is associated with a range of human pathologies, including the neurodegenerative diseases, systemic amyloidosis, type II diabetes, etc. Despite significant progress in elucidating the mechanisms of cytotoxic action of amyloid fibrils, the role of fibril-protein interactions in determining the amyloid toxicity remains poorly understood. In view of this, in the present study the molecular docking techniques has been employed to investigate the interactions between the insulin amyloid fibrils (InsF) and three biologically important multifunctional proteins, <em>viz.</em> serum albumin, lysozyme and insulin in their native globular state. Using the ClusPro, HDOCK, PatchDock and COCOMAPS web servers, along with BIOVIA Discovery Studio software, the structural characteristics of fibril-protein complexes such as the number of interacting amino acid residues, the amount of residues at fibril and protein interfaces, the contributions of various kinds of interactions, buried area upon the complex formation, etc. It was found that i)&nbsp;hydrophilic-hydrophilic and hydrophilic-hydrophobic interactions play dominating role in the formation of fibril-protein complexes; ii)&nbsp;there is no significant differences between the investigated proteins in the number of fibrillar interacting residues; iii) the dominating hydrogen bond forming residues are represented by glutamine and asparagine in fibrillar insulin, lysine in serum albumin and arginine in lysozyme; iv) polar buried area exceeds the nonpolar one upon the protein complexation with the insulin fibrils. The molecular docking evidence for the localization of phosphonium fluorescent dye TDV at the fibril-protein interface was obtained.</p> 2022-06-02T00:00:00+00:00 Copyright (c) 2022 Valeriya Trusova, Olga Zhytniakivska, Uliana Tarabara, Kateryna Vus, Galyna Gorbenko Electronic Chips Acting as Capacitors or Inductors when Laser Act as Information Transmitter 2022-06-02T18:20:36+00:00 Mashair Ahmed Mohammed Yousef Abdullah Saad Alsubaie Zoalnoon Ahmed Abeid Allah Saad Mubarak Dirar Abd-Alla <p>To increase the speed of information flow and storage capacity in electronic devices laser can be used to carry information instead of electric current. Since the photon is faster than electrons, one expects information to be transmitted very fast through the internet when photons replace electrons. This requires searching for chips that act as capacitors, inductors or resistors. To do this Maxwell's equation for the electric field intensity beside the electron equation of motion were used. The electron is assumed to vibrate naturally inside a frictional medium in the presence of a local electric and magnetic fields. These equations have been used to find a useful expression for the absorption coefficient. The absorption coefficient was found to be dependent on the laser and natural frequencies beside the coefficient of friction in addition to the internal electric and magnetic fields. These parameters can be fine-tuned to make the chip act as a capacitor, inductor or resistor. The laser intensity decreases when the absorption coefficient inecreases. Thus, the absorption coefficient acts as an electic resistor. Therefore, if the absorption coefficient inecreases upon decreasing the frequency the chip acts as a capacitor. But when the absorption coefficient inecreases when the laser frequency inreases the chip acts as an inductor. In the case that the absorption coefficient inecreases with the concentration of the carriers it acts in this situation as a resistor. For magnetic materials with magnetic flux density that cancels the frictional force, when the laser frequency is equal nearly to the atom’s natural frequency the material acts as an inductor. But when the frictional force is low with the internal and external electric fields in phase, the material acts as a capacitor. However, it acts as a resistor for negligible natural frequency, when no electric dipoles exist and when the internal magnetic field force balance the frictional force.</p> 2022-06-02T00:00:00+00:00 Copyright (c) 2022 M.A.M. Yousef, A.S. Alsubaie, Z.A.A.A. Saad, M.D. Abd-Alla Solutions of the Schrödinger Equation with Hul Neutron Position for Beta (β-) Decay and Neutron Emission 2022-06-02T18:20:38+00:00 Waleed S. Hwash <p>The current study is about the structure of <sup>17</sup>B, which has been investigated by the Microscopic Cluster Model. The binding energy and neutron position of two valence neutrons of Beta-decay and neutron emission have been calculated. A cluster configuration of the Halo nucleus inspired me to consider all radioisotopes have cluster configuration before the decay process. The Jacobi coordinates has been used to investigated the <sup>17</sup>B nucleus. The Jacobi coordinate is a very well technique to describe such as a three-body system or halo structure. The <sup>17</sup>B has Borromean property, so it has been defined in T-configuration in this coordinates. The angle in the figure defines an angle of halo neutron motion around the core. The study has considered a deformation of the core as a high influence on the binding of the valence neutrons.</p> 2022-06-02T00:00:00+00:00 Copyright (c) 2022 Waleed Hwash Use of Nonlinear Operators for Solving Geometric Optics Problems 2022-06-02T18:20:36+00:00 Ilia V. Demydenko <p>The aim of this work is to develop and apply a mathematical apparatus based on nonlinear operators for solving problems of geometric optics, namely the construction of images of objects in systems of thin lenses. The problem of constructing the image of a point in a thin lens was considered, on the basis of which the concept of the lensing operator was defined. The mathematical properties of the operator were investigated. The model problem of constructing an image in thin lenses folded together was investigated, on the basis of which it became possible to establish a physical interpretation of the previously determined properties. The problem of a system of lenses located at a distance was also considered, which resulted in the introduction of the concept of shift operator. The properties of the shift operator were studied, which together with the properties of the lens operator made it possible to determine the rules for using the created operators for solving the problems. In addition to solving the model problems, the following problems were considered: the speed of the moving point image, the magnification factor and the construction of the curve image. As an example, images of a segment and an arc of the circle were constructed. The segment was transformed into the segment, and the arc of the circle into the arc of the curve of the second order. The presented mathematical apparatus is very convenient for implementation in computer programs, as well as for the study of images of different curves.</p> 2022-06-02T00:00:00+00:00 Copyright (c) 2022 Ilia V. Demydenko