East European Journal of Physics最新文献_第4页

Numerical Investigation of Thermophoresis and Activation Energy Effects on Maxwell Nano Fluid Over an Inclined Magnetic Field Applied to a Disk 麦克斯韦纳米流体在施加于磁盘的倾斜磁场上的热泳和活化能效应的数值研究

IF 0.4

East European Journal of Physics Pub Date : 2023-12-02 DOI: 10.26565/2312-4334-2023-4-43

Dudekula Dastagiri Babu, S. Venkateswarlu, E. K. Reddy

{"title":"Numerical Investigation of Thermophoresis and Activation Energy Effects on Maxwell Nano Fluid Over an Inclined Magnetic Field Applied to a Disk","authors":"Dudekula Dastagiri Babu, S. Venkateswarlu, E. K. Reddy","doi":"10.26565/2312-4334-2023-4-43","DOIUrl":"https://doi.org/10.26565/2312-4334-2023-4-43","url":null,"abstract":"Numerical model is conducted to investigate the behavior of an incompressible Maxwell nanofluid model flow on a convectively stretched surface, considering the effects of thermophoresis and an inclined magnetic field. The system, originally formulated as a set of partial differential equations, is transformed into a system of ordinary differential equations using similarity transformations. The resulting equations are solved using the Runge-Kutta-Fehlberg method in conjunction with the shooting technique. The obtained physical parameters from the derived system are presented and discussed through graphical representations. The numerical process is assessed by comparing the results with existing literature under various limiting scenarios, demonstrating a high level of proficiency. The key findings of this study indicate that the velocity field decreases as the fluid parameters increase, while the fluid temperature diminishes accordingly. Additionally, the heat transfer rate decreases with increasing fluid and thermophoresis parameters, but it increases with Biot and Prandtl numbers.","PeriodicalId":42569,"journal":{"name":"East European Journal of Physics","volume":null,"pages":null},"PeriodicalIF":0.4,"publicationDate":"2023-12-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139187456","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Investigation of the Magnetic Properties of Silicon Doped with Rare-Earth Elements 掺杂稀土元素的硅的磁性能研究

IF 0.4

East European Journal of Physics Pub Date : 2023-12-02 DOI: 10.26565/2312-4334-2023-4-18

Khodjakbar S. Daliev, Zavkiddin E. Bahronkulov, Jonibek J. Hamdamov

引用次数: 0

Electronic Structure Calculation of α-Al2X3 System (X = O, S) Based on R++Scan Functional 基于 R++Scan 函数的 α-Al2X3 系统（X = O、S）电子结构计算

IF 0.4

East European Journal of Physics Pub Date : 2023-12-02 DOI: 10.26565/2312-4334-2023-4-26

Muhammad R. Ramadhan, Salwa A. Khansa, Qoriana Zulindra, Dian P. Handayani, Nina A. Wardani, Fahmia Astuti

{"title":"Electronic Structure Calculation of α-Al2X3 System (X = O, S) Based on R++Scan Functional","authors":"Muhammad R. Ramadhan, Salwa A. Khansa, Qoriana Zulindra, Dian P. Handayani, Nina A. Wardani, Fahmia Astuti","doi":"10.26565/2312-4334-2023-4-26","DOIUrl":"https://doi.org/10.26565/2312-4334-2023-4-26","url":null,"abstract":"Due to the necessity of reducing the reliance on fossil fuels, several systems are considered to be alternative and/or additional support for the existing battery material. In this report, structural and electronic properties of aluminium oxide (Al2O3) and aluminium sulfide (Al2S3) with hexagonal symmetry (α-phase), are investigated by utilizing density functional theory technique based on r++SCAN functional. The calculated lattice parameter and insulating gap for both systems are well matched with previous experimental studies and display higher accuracy compared to the results from local density approximation (LDA) and generalized gradient approximation (GGA) studies. The calculated insulating gap values are 10.3 eV and 4.1 eV for α-Al2O3 and α-Al2S3 respectively. For α-Al2O3 system, we observed hybridized s-p-d orbital of Al-O in the conduction states, consistent with the interpretation of past X-ray Absorption Near Edge Structure (XANES) data. Finally, the bulk and young modulus for α-Al2O3 are determined to be 251 GPa and 423 GPa which is very close to the known experimental values of 280 GPa and 451 GPa.","PeriodicalId":42569,"journal":{"name":"East European Journal of Physics","volume":null,"pages":null},"PeriodicalIF":0.4,"publicationDate":"2023-12-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139187494","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Study of the Mobility and Electrical Conductivity of Chromium Silicide 硅化铬的迁移性和导电性研究

IF 0.4

East European Journal of Physics Pub Date : 2023-12-02 DOI: 10.26565/2312-4334-2023-4-22

M. Isaev, Tokhirjon U. Atamirzaev, Mukhammadsodik N. Mamatkulov, Uralboy T. Asatov, Makhmudjon A. Tulametov

引用次数: 0

Effect of Arrhenius Activation Energy in MHD Micropolar Nanofluid Flow Along a Porous Stretching Sheet with Viscous Dissipation and Heat Source 具有粘性耗散和热源的多孔拉伸片上的 MHD 微波纳米流体流动中阿伦尼乌斯活化能的影响

IF 0.4

East European Journal of Physics Pub Date : 2023-12-02 DOI: 10.26565/2312-4334-2023-4-10

Keshab Borah, Jadav Konch, Shyamanta Chakraborty

{"title":"Effect of Arrhenius Activation Energy in MHD Micropolar Nanofluid Flow Along a Porous Stretching Sheet with Viscous Dissipation and Heat Source","authors":"Keshab Borah, Jadav Konch, Shyamanta Chakraborty","doi":"10.26565/2312-4334-2023-4-10","DOIUrl":"https://doi.org/10.26565/2312-4334-2023-4-10","url":null,"abstract":"A numerical study of the heat and mass transfer of a micropolar nanofluid flow over a stretching sheet embedded in a porous medium is carried out in this investigation. The main objective of this work is to investigate the influence of Arrhenius activation energy, heat source and viscous dissipation on the fluid velocity, microrotation, temperature, and concentration distribution. The equations governing the flow are transformed into ordinary differential equations using appropriate similarity transformations and solved numerically using bvp4c solver in MATLAB. Graphs are plotted to study the influences of important parameters such as magnetic parameter, porosity parameter, thermophoresis parameter, Brownian motion parameter, activation energy parameter and Lewis number on velocity, microrotation, temperature and concentration distribution. The graphical representation explores that the velocity of the liquid diminishes for increasing values of magnetic parameter, whereas the angular velocity increases with it. This study also reports that an enhancement of temperature and concentration distribution is observed for the higher values of activation energy parameter, whereas the Lewis number shows the opposite behavior. The effects of various pertinent parameters are exposed realistically on skin friction coefficient, Nusselt and Sherwood numbers via tables. A comparison with previous work is conducted, and the results show good agreement.","PeriodicalId":42569,"journal":{"name":"East European Journal of Physics","volume":null,"pages":null},"PeriodicalIF":0.4,"publicationDate":"2023-12-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139187609","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Effect of Compensation Degree and Concentration of Impurity Electroactive Selenium Atoms on Current Auto-Oscillation Parameters in Silicon 杂质电活性硒原子的补偿度和浓度对硅中电流自振参数的影响

IF 0.4

East European Journal of Physics Pub Date : 2023-12-02 DOI: 10.26565/2312-4334-2023-4-31

N. F. Zikrillaev, Kutub S. Ayupov, Manzura M. Shoabdirahimova, F. E. Urakova, Yoldoshali A. Abduganiev, Abdujalol A. Sattorov, Latofat S. Karieva

{"title":"Effect of Compensation Degree and Concentration of Impurity Electroactive Selenium Atoms on Current Auto-Oscillation Parameters in Silicon","authors":"N. F. Zikrillaev, Kutub S. Ayupov, Manzura M. Shoabdirahimova, F. E. Urakova, Yoldoshali A. Abduganiev, Abdujalol A. Sattorov, Latofat S. Karieva","doi":"10.26565/2312-4334-2023-4-31","DOIUrl":"https://doi.org/10.26565/2312-4334-2023-4-31","url":null,"abstract":"One of the crucial phenomena is auto-oscillations of current in elementary and binary (AIIIBV, AIIBVI) semiconductor materials, which allow the creation of solid-state oscillators with a wide frequency range from 10-3 to 10-6 Hz. In this paper, we show the results of a study on the effect of the degree of compensation (K) and the concentration of electroactive impurity selenium atoms on the excitation conditions and parameters (amplitude, frequency) of the auto-oscillation current associated with temperature and electrical instability in silicon. In the research, silicon doped with selenium atoms Si of identical geometrical dimensions has been used. The compensation degree of the initial boron atoms with impurity selenium atoms in the samples is in the range of K = 2NB/NSe = 0.94-1.1. It was found that excitation conditions, the amplitude and frequency of auto-oscillation current significantly vary depending on the degree of compensation of selenium atoms with boron atoms in the initial silicon. Obtained experimental results showed that the auto-oscillation current in silicon doped with impurity selenium atoms is characterized by ease of control with stable parameters (amplitude and frequency), which makes it possible based on this unique physical phenomenon to develop and create oscillatory circuits in information technology.","PeriodicalId":42569,"journal":{"name":"East European Journal of Physics","volume":null,"pages":null},"PeriodicalIF":0.4,"publicationDate":"2023-12-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139187705","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Instability of Ion Cyclotron Waves (ICWS) at the Expense of Lower Hybrid Drift Waves (LHDWS) Turbulence Energy 以较低混合漂移波 (LHDWS) 湍流能量为代价的离子回旋波 (ICWS) 的不稳定性

IF 0.4

East European Journal of Physics Pub Date : 2023-12-02 DOI: 10.26565/2312-4334-2023-4-06

Raksha Mundhra, P. Deka

{"title":"Instability of Ion Cyclotron Waves (ICWS) at the Expense of Lower Hybrid Drift Waves (LHDWS) Turbulence Energy","authors":"Raksha Mundhra, P. Deka","doi":"10.26565/2312-4334-2023-4-06","DOIUrl":"https://doi.org/10.26565/2312-4334-2023-4-06","url":null,"abstract":"Instability of ion cyclotron waves(ICWs) is investigated in presence of lower hybrid drift waves(LHDWs) turbulence. Plasma inhomogeneity in the Earth’s magnetopause region supports a range of low frequency drift wave turbulent fields due to gradients in density in different regions of the media. One of these drift phenomena is identified as lower hybrid drift waves (LHDWs) which satisfies resonant conditions ω − k · v = 0. We have considered a nonlinear wave-particle interaction model where the resonant wave that accelerates the particle in magnetopause may transfer its energy to ion cyclotron waves through a modulated field. In spite of the frequency gaps between the two waves, energy can be transferred nonlinearly to generate unstable ion cyclotron waves which always do not satisfy the resonant condition Ω−K · v ≠ 0 and the nonlinear scattering condition Ω − ω − (K − k) · v ̸= 0. Here, ω and Ω are frequencies of the resonant and the nonresonant waves respectively and k and K are the corresponding wave numbers. We have obtained a nonlinear dispersion relation for ion cyclotron waves(ICWs) in presence of lower hybrid drift waves(LHDWs)turbulence. The growth rate of the ion cyclotron waves using space observational data in the magnetopause region has been estimated.","PeriodicalId":42569,"journal":{"name":"East European Journal of Physics","volume":null,"pages":null},"PeriodicalIF":0.4,"publicationDate":"2023-12-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139187454","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Dangerous Bonds Individual of Hydrogenated Amorphous Silicon and Defect Absorption Spectra 氢化无定形硅的危险键个体和缺陷吸收光谱

IF 0.4

East European Journal of Physics Pub Date : 2023-12-02 DOI: 10.26565/2312-4334-2023-4-30

Rustamjon G. Ikramov, K. Muminov, M. Nuritdinova, Bobur Q. Sutonov, Oybek T. Kholmirzayev, A’zamxo’ja A. Mamakhanov

引用次数: 0

Cathodic Vacuum ARC Multilayer Coatings (TiZrSiY)N/NbN: Structure and Properties Depending on The Deposition Interval of Alternate Layers 阴极真空 ARC 多层涂层 (TiZrSiY)N/NbN：取决于交替层沉积间隔的结构和特性

IF 0.4

East European Journal of Physics Pub Date : 2023-12-02 DOI: 10.26565/2312-4334-2023-4-45

V. Beresnev, S. Lytovchenko, M. Azarenkov, O. Maksakova, D. V. Horokh, B. O. Mazilin, Diana Kaynts, I. Doshchechkina, Оleg V. Gluhov

{"title":"Cathodic Vacuum ARC Multilayer Coatings (TiZrSiY)N/NbN: Structure and Properties Depending on The Deposition Interval of Alternate Layers","authors":"V. Beresnev, S. Lytovchenko, M. Azarenkov, O. Maksakova, D. V. Horokh, B. O. Mazilin, Diana Kaynts, I. Doshchechkina, Оleg V. Gluhov","doi":"10.26565/2312-4334-2023-4-45","DOIUrl":"https://doi.org/10.26565/2312-4334-2023-4-45","url":null,"abstract":"Two series of multilayer coatings with different numbers of bilayers (268 and 536, respectively) were synthesised using the cathodic vacuum-arc deposition (CVAD) with the simultaneous sputtering of two different cathodes. The first cathode was made of the multicomponent TiZrSiY material, and the second one was made of technical niobium. The coatings were condensed in a nitrogen atmosphere at a constant negative bias potential applied to the substrate. The resulting coatings have a distinct periodic structure composed of individual layers of (TiZrSiY)N and NbN with the thicknesses determined by the deposition interval (10 or 20 s, respectively). The total thicknesses of the coatings determined by the number of bilayers were 11 and 9 microns, respectively. The formation of polycrystalline TiN and NbN phases with grain size comparable to the size of the layers has been identified for both series of coatings. The layers exhibit a columnar structure growth with a predominant orientation (111). The hardness of the experimental coatings depends on the thickness of the layers and reaches 39.7 GPa for the coating with the smallest layer thickness. The friction coefficient of the obtained coatings varies from 0.512 to 0.498 and also depends on the thickness of the layers. A relatively large value of the friction coefficient is due to high roughness and the presence of a droplet fraction on the surface as well as in the volume of the coatings.","PeriodicalId":42569,"journal":{"name":"East European Journal of Physics","volume":null,"pages":null},"PeriodicalIF":0.4,"publicationDate":"2023-12-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139187682","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Influence of Aperture of Radiating Strip Structure on Electrodynamic Characteristics of Patch Antenna 辐射带结构孔径对贴片天线电动特性的影响

IF 0.4

East European Journal of Physics Pub Date : 2023-12-02 DOI: 10.26565/2312-4334-2023-4-34

S. Pogarsky, D. Mayboroda, Serhii M. Mykhaliuk

{"title":"Influence of Aperture of Radiating Strip Structure on Electrodynamic Characteristics of Patch Antenna","authors":"S. Pogarsky, D. Mayboroda, Serhii M. Mykhaliuk","doi":"10.26565/2312-4334-2023-4-34","DOIUrl":"https://doi.org/10.26565/2312-4334-2023-4-34","url":null,"abstract":"The paper presents the results of numerical modeling of the electrodynamic characteristics of a Vivaldi type patch antenna based on a circular disk resonator. The modeling was carried out using the semi-open resonator model by the finite element method (FEM) implemented in the HFFS package. The antenna was fed using a coplanar line segment. The antenna elements were placed over a grounded plane. The influence of design parameters and the function determining the curvature of the exponentially expanding slot discontinuity on the frequency, energy and polarization characteristics was investigated. It was established that with a certain selection of variable parameters, such an antenna can be matched with external circuits in the range from 7.03 GHz to 20 GHz with a level of VSWR values not exceeding 1.92. In the amplitude-frequency characteristic, fairly wide frequency bands with almost perfect matching are observed. The choice of the type of excitation element in the form of a section of the coplanar line made it possible to exclude additional elements inherent in Vivaldi antennas, namely, a section of the auxiliary strip line and a balancing resonator. This kind of antenna allows to form radiation patterns of various shapes from single-sided to cosecant quadrate. At the same time, in some intervals of observation angles, the formed fields turn out to be elliptically polarized with an ellipticity coefficient close to unity. The combination of the obtained results makes it possible to predict the use of this kind of antennas for operation with broadband signals.","PeriodicalId":42569,"journal":{"name":"East European Journal of Physics","volume":null,"pages":null},"PeriodicalIF":0.4,"publicationDate":"2023-12-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139187479","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0