51(2022)最新文献

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Alternative Representation of Space and Time: Geometric Solution of Problems of Relativity Theory 空间和时间的替代表示:相对论问题的几何解
51(2022) Pub Date : 2022-06-20 DOI: 10.54919/2415-8038.2022.51.74-82
Iurii Shynkariuk
{"title":"Alternative Representation of Space and Time: Geometric Solution of Problems of Relativity Theory","authors":"Iurii Shynkariuk","doi":"10.54919/2415-8038.2022.51.74-82","DOIUrl":"https://doi.org/10.54919/2415-8038.2022.51.74-82","url":null,"abstract":"Relevance. The relevance of the stated subject of this scientific research is due to the importance of theoretical issues of alternative representation of the categories of space and time from the point of view of developing geometric solutions to problems of relativity theory, which are important in solving numerous practical issues encountered in various fields of modern science and technology.Purpose. The purpose of this research work is to form an alternative view of the categories of space and time, which are of significant practical importance for creating geometric solutions to problems that reflect certain principles of the theory of relativity.Methods. The basis of the methodological approach to the construction of research works in this scientific study was a combination of a systematic analysis of the features of compiling an alternative representation of the categories of space and time with an analytical study of the features of constructing geometric solutions to problems that reflect various problematic aspects of the general theory of relativity.Results. The results of this research work reflect the entire course of scientific research, and indicate the absence of contradictions in the very fact of the existence of alternative space-time models, as not meeting the fundamental principles of the special theory of relativity.Conclusions. The results and conclusions of this research have significant practical significance from the point of view of forming new ideas about the provisions of the special theory of relativity and the possibilities of practical use of geometric models to solve complex problems of this theory, through the use of corrected ideas about the real properties of space and time, and are also of significant importance for employees of design bureaus engaged in the development of the latest samples of high-tech equipment and using the principles of special relativity in their calculations","PeriodicalId":377176,"journal":{"name":"51(2022)","volume":"47 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-06-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121858537","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: 6
Effects of Repulsion and Attraction between Rotating Cylinders in Fluids 流体中旋转圆柱体之间的排斥和吸引效应
51(2022) Pub Date : 2022-06-15 DOI: 10.54919/2415-8038.2022.51.39-47
Vadym Ostanin
{"title":"Effects of Repulsion and Attraction between Rotating Cylinders in Fluids","authors":"Vadym Ostanin","doi":"10.54919/2415-8038.2022.51.39-47","DOIUrl":"https://doi.org/10.54919/2415-8038.2022.51.39-47","url":null,"abstract":"Relevance. From the theory of hydrodynamics, it is known about the interaction of a pair of vortices in inviscid fluids. The relevance of the study is conditioned upon the presence of many studies of numerical simulations of the interactions of two vortices or two cylinders, but the lack of research of practical installations for observing the effects of attraction and repulsion in fluid media may slow down research in this area for practical application.\u0000\u0000Purpose. The purpose of this study is a practical demonstration of the possibility of the effect of double interaction in the air, with the calculation of the approximate magnitude of the force tending to attract or repel each of the cylinders.\u0000\u0000Methods. In a practical experiment, a pair of plastic cylinders are used, which are driven by engines and rotate next to each other in the air at atmospheric pressure. Numerical simulation of the effect shows the nature of the effect and allows predicting the magnitude of the force generated by rotating cylinders on each other. The relationship between the directions of rotation of the cylinders and the observed effects was verified by numerical simulation using numerical simulation of finite volumes of OpenFOAM version 9.\u0000\u0000Results. In a practical experiment, a pair of rotating cylinders started interacting at 5-7 cm in the experiment, which at a smaller distance of 2-3 cm created sufficient force to stabilise the vibrations of one of the cylinders around the thread for which it is suspended. Numerical simulation shows that a zone of high or low pressure is formed in the space between the cylinders, depending on the direction of rotation. The rotation of adjacent disks with opposite directions of rotation helps the circulation of the other cylinder to maintain the flow velocity in the gap, which reduces the fluid pressure between the rotating disks and attracts them. Conversely, rotating disks with the same direction extinguish and compress fluid flows in the gap, which increases the air pressure between rotating objects above the stationary pressure and repels them.\u0000\u0000Conclusions. The results of the study provide a better understanding of the processes of fluid interaction, link the dependence of the interaction force on the parameters of the medium and cylinders, and demonstrate the practical possibility of applying the effects of interaction in fluid media","PeriodicalId":377176,"journal":{"name":"51(2022)","volume":"121 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-06-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115749173","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: 4
Study of the Cross-Section for the 122Te(γ, n)121Te Reaction by the Activation Method 活化法研究122Te(γ, n)121Te反应的截面
51(2022) Pub Date : 2022-06-15 DOI: 10.54919/2415-8038.2022.51.18-23
O. Pop, V. Mazur, P. Derechkei, Z. Bigan
{"title":"Study of the Cross-Section for the 122Te(γ, n)121Te Reaction by the Activation Method","authors":"O. Pop, V. Mazur, P. Derechkei, Z. Bigan","doi":"10.54919/2415-8038.2022.51.18-23","DOIUrl":"https://doi.org/10.54919/2415-8038.2022.51.18-23","url":null,"abstract":"Relevance. The study of photonuclear reactions plays a defining role in the formation of modern ideas about highlocalized collective excitations in nuclei of the giant resonance type. The giant dipole E1-resonance (GR) is the main feature in γ-quantum absorption cross-sections of nuclei. The presence of isotopes with multiple isotopes makes it possible to trace the evolution of GR characteristics from changes in the number of neutrons in the nuclei. One such element is tellurium.\u0000\u0000Purpose. The purpose of this research is an experimental and theoretical study of the cross-section of 122Te(γ, n)121Te reaction in the region of giant E1-resonance energies.\u0000\u0000Methods. The study of the cross-section of (γ, n) reaction on 122Te isotope was performed on the bremsstrahlung γ-beam of the M-30 microtron of the Institute of Electronic Physics of the National Academy of Sciences of Ukraine. The yield curves were measured in the range of maximum gamma-quantum energies Eγmax=10-18 MeV. The reaction cross-section was calculated by the inverse matrix method. When registering the reaction products, an activation technique was used, while the gamma activity of the products was recorded by the spectrometric method. The theoretical calculations of the cross-section for the 122Te(γ, n)121Te reaction were performed using the TALYS-1.9 software package.\u0000\u0000Results. The measured experimental yield ratios of the 122Te(γ, n)121Te і 130Te(γ, n)129Te d= Yn121 /Yn129 = f (E max) reactions allowed the experimental cross-section for the 122Te(γ, n)121Te reaction to be calculated. The cross-section has a single hump shape with a maximum at an energy of ~ 15.3 MeV. It was approximated by the Lorentz curve with the parameters δ0 =(274.1±2.1) MB, Е0 (15.27±0.10) MeV, Г0 =(4.76±0.08) MeV. The cross-section obtained was compared with similar cross-sections for 126Te and 130Te isotopes, as well as with theoretical calculations according to the TALYS-1.9 program.\u0000\u0000Conclusions. The obtained cross-section for the 122Te(γ, n)121Te reaction is consistent with the evolution of the parameters of (γ, n) reaction cross-section on tellurium isotopes 130Te(γ, n)129Te with a change in the number of neutrons. The theoretical approaches used are satisfactorily consistent with the experimental data. This agreement indicates the main contribution of the statistical mechanism to the cross-section of the considered (γ, n) reaction and a relatively small contribution of semi-direct processes","PeriodicalId":377176,"journal":{"name":"51(2022)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-06-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128913946","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: 1
Nonlinear Surface Polaritons near the Interface between a Magneto-Optical Substance and a Nonlinear Metamaterial with a Permittivity Close to Zero 磁光物质与介电常数接近于零的非线性超材料界面附近的非线性表面极化子
51(2022) Pub Date : 2022-06-15 DOI: 10.54919/2415-8038.2022.51.24-29
Andriy Groza, N. Siddelev
{"title":"Nonlinear Surface Polaritons near the Interface between a Magneto-Optical Substance and a Nonlinear Metamaterial with a Permittivity Close to Zero","authors":"Andriy Groza, N. Siddelev","doi":"10.54919/2415-8038.2022.51.24-29","DOIUrl":"https://doi.org/10.54919/2415-8038.2022.51.24-29","url":null,"abstract":"Relevance. Considerable attention of researchers is drawn to nonlinear surface optical waves, as they are promising for application in optical information processing systems, ultra-sensitive sensors, and modern telecommunications components.\u0000\u0000Purpose. To obtain an exact solution of the Maxwell equation system for TM-polarised nonlinear surface polaritons propagating along the interface between an optically linear magnetic medium and an optically nonlinear medium with saturated nonlinearity.\u0000\u0000Methods. Analysis of the properties of nonlinear surface polaritons (NSP) and mathematical modelling of the dependence of the permittivity of a nonlinear medium on the intensity are used.\u0000\u0000Results. TM-polarised nanoparticles propagating along the interface of a magneto-optical medium and a nonlinear optical metamaterial with a permittivity close to zero (ENZ-metamaterial) are studied. For NSP in such a structure, an exact solution of the Maxwell equation system is obtained, considering the saturation effect of optical nonlinearity. On this basis, the dependences of constant propagation on the total energy flux of NSP and energy fluxes in contact media in the structure were investigated: magneto-optical ENZ-metamaterial with negative permittivity/nonlinear self-focusing ENZ-metamaterial.\u0000\u0000Conclusions. The NSP energy flow is positive in a nonlinear medium and negative in a linear one. As the saturation level decreases, the NSP energy fluxes in the contacting media increase modulo, if the value of the NSP propagation constant (NSPPC) is fixed. The lowest NSPPC value for guiding nonlinearity is obtained when the total energy flow of the NSP becomes zero. As the saturation level decreases, the NSP propagation variable (NSPPV) increases. At a fixed NSPPC, with a decrease in the magnetic permeability, the energy fluxes of NSP in the contacting media increase. When the magnetic permeability decreases to zero and the NSP energy flux is positive, the NSPPV change range narrows","PeriodicalId":377176,"journal":{"name":"51(2022)","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-06-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125428035","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
A Simple Model for Describing the Minimum Differential Cross-Section of Elastic Proton Scattering on Protons at High Energies 描述弹性质子在高能质子上散射最小微分截面的简单模型
51(2022) Pub Date : 2022-06-15 DOI: 10.54919/2415-8038.2022.51.30-38
N. Bence, A. Lengyel, Z. Tarics
{"title":"A Simple Model for Describing the Minimum Differential Cross-Section of Elastic Proton Scattering on Protons at High Energies","authors":"N. Bence, A. Lengyel, Z. Tarics","doi":"10.54919/2415-8038.2022.51.30-38","DOIUrl":"https://doi.org/10.54919/2415-8038.2022.51.30-38","url":null,"abstract":"Relevance. The most modern and widely applied phenomenological theory, which well describes an entire range of physical characteristics of such processes as elastic and inelastic proton-proton and antiproton-proton scattering at high energies, is the Regge poles method in relativistic theory. Based on a simple amplitude, such as the dipole pomeron, where the pomeron is the Regge pole, the researchers add different terms to it. Using such more complex amplitudes, it is possible to explain well or satisfactorily together not only the experimental data for these reactions obtained at the end of the last century, but also the latest ones obtained at the Large Hadron Collider.\u0000\u0000Purpose. The purpose of this study is to find numerical values of the amplitude parameters at which the circumferences of the differential cross-sections of elastic proton scattering on protons at high energies are satisfactorily described, and to answer whether the parameters satisfy the obtained constraints.\u0000\u0000Methods. To find the amplitude parameters, the least squares method is used and minima equations are obtained for the squares of differences between the experimental and theoretical values of these cross-sections. These equations are transcendental, and therefore, they are solved by approximation. Within the framework of successive approximations, a method is selected that ensures fast convergence of the process, namely: the faster descent method or the gradient method. Parameter errors are calculated using a covariance matrix. The statistical acceptability of the model is determined according to the Fischer criterion.\u0000\u0000Results. Numerical calculations from experimental data of differential cross-sections of elastic pp-scattering were used to find the values of the parameters and the scale multiplier of the amplitude. Differential cross-sections are calculated from the amplitude near the minima. The corresponding graphs of these cross-sections are presented. The coincidence with the experiment is satisfactory in most cases, and in some cases, it is of high quality. A covariance matrix is obtained, from which the errors of the model parameters are found. Under general conditions, restrictions on the found approximate values of parameters are derived. It is shown that they satisfy the constraint. According to the Fischer criterion, the statistical acceptability of the model was verified, which turned out to be positive.\u0000\u0000Conclusions. The proposed simple amplitude ensures that the Froissard constraint and unitarity are met. It will serve as a seed for constructing more complex amplitudes that will describe a wide range of experiments on proton-proton and antiproton-proton scattering at high energies.","PeriodicalId":377176,"journal":{"name":"51(2022)","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-06-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127936017","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
Mass Spectrometric Studies of Valine Molecules by Electron Shock in the Gas Phase 气相电子激波质谱法研究缬氨酸分子
51(2022) Pub Date : 2022-06-15 DOI: 10.54919/2415-8038.2022.51.9-17
A. Bulhakova
{"title":"Mass Spectrometric Studies of Valine Molecules by Electron Shock in the Gas Phase","authors":"A. Bulhakova","doi":"10.54919/2415-8038.2022.51.9-17","DOIUrl":"https://doi.org/10.54919/2415-8038.2022.51.9-17","url":null,"abstract":"Relevance. Valine is one of the eight amino acids not synthesised by the human body, necessary for the synthesis and growth of body tissues, muscle coordination; regulation of nervous processes, nitrogen metabolism, and stabilisation of the hormonal background. Since α-amino acids contain an asymmetric carbon atom, they can exist as optical isomers (mirror antipodes) that play an essential role in protein biosynthesis. The structure of matter and the physical processes that occur in it are studied using the method of mass spectrometry and spectral analysis. This indicates the relevance of the problem that was studied in this paper.\u0000\u0000Purpose. Mass spectrometric studies of the formation of ionic products of single and dissociative ionisation of the valine molecule (C5 H11NO2) with electrons according to the method of beams intersecting within the energy range of bombarding electrons 6-70 eV. To consider the mechanisms of formation of the most intense ion fragments during dissociative ionisation by electron shock.\u0000\u0000Methods. The experiment was conducted on an installation with a monopole mass spectrometer of the MX-7304A type, which belongs to the class of dynamic mass analysers with electron shock ionisation in the range of mass numbers 0-120 Da. The mass spectra of molecules were investigated at different temperatures of the source of molecules in the range of 300-600 K.\u0000\u0000Results. The obtained results are compared with the mass spectra of the D-, L-, and DL-enantiomeric forms of the valine molecule with data from the NIST and SDBS databases. The features of the processes of formation of ion fragments of valine molecules by electronic shock are analysed in detail, and the dynamics of the yield of ion fragments in the range of evaporation temperatures of the initial substance of 300-440 K is also studied. The total relative ionisation cross-section of the molecule under study was measured according to mass spectrometric method with an ionising electron energy of 5-60 eV. Based on the results of experimental studies, a threshold section of the dependence of the total relative cross-section of valine ionisation is determined and given in this paper.\u0000\u0000Conclusions. A detailed analysis of the processes of formation of fragment ions in the mass spectra allows demonstrating the influence of the structural forms of valine enantiomers on the redistribution of relative intensities of product ions","PeriodicalId":377176,"journal":{"name":"51(2022)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-06-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123179450","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: 2
Optimisation of Dynamic Loads of Rope Systems of Lifting Mechanisms of Bridge Cranes During Cargo Handling 桥式起重机起升机构绳索系统在货物装卸过程中的动态载荷优化
51(2022) Pub Date : 2022-06-06 DOI: 10.54919/2415-8038.2022.51.59-73
Y. Chovnyuk, L. Diachenko, Yevhen A. Ivanov, Nataliya Dichek, O. Orel
{"title":"Optimisation of Dynamic Loads of Rope Systems of Lifting Mechanisms of Bridge Cranes During Cargo Handling","authors":"Y. Chovnyuk, L. Diachenko, Yevhen A. Ivanov, Nataliya Dichek, O. Orel","doi":"10.54919/2415-8038.2022.51.59-73","DOIUrl":"https://doi.org/10.54919/2415-8038.2022.51.59-73","url":null,"abstract":"Relevance. In this study, considerable attention is devoted to the analysis of dynamic loads that occur in the rope systems of lifting mechanisms of overhead cranes during start-up and braking, and the reduction of these loads.Purpose. To identify the magnitude and nature of changes in dynamic loads in the elements of lifting mechanisms of bridge cranes, a comprehensive dynamic analysis of the lifting mechanism of the bridge crane and its elastic elements (rope systems) was performed.Methods. The dynamic analysis of the above mechanisms and systems was performed on well-grounded mathematical models of bridge-type cranes (single- and double-mass).Results. The analysis of the obtained calculations of mathematical models of the mechanism of lifting the load of bridge cranes demonstrated that the dynamic loads applied to the structural elements and drive mechanisms are oscillatory and comparable to static loads. The analysis of the obtained calculations of mathematical models of the mechanism of lifting the load of bridge cranes demonstrated that the dynamic loads applied to the structural elements and drive mechanisms are oscillatory and comparable to static loads. To minimise the integral functionals, the methods of classical calculus of variations, mathematical physics and differential equations were used to model the dynamics of loading processes of rope systems and drives of bridge cranes, and the terminal (initial and final conditions of movement of such systems) were considered, which allowed solving the optimisation problem unambiguouslyThus, to reduce dynamic loads in structural elements (in particular, in ropes) during transients in such lifting mechanisms of bridge cranes, it is proposed to perform optimisation of the modes of movement of their drive mechanisms. An essential place in such optimisation is occupied by the choice of the optimisation criterion. Among such criteria, integral optimisation criteria were used. As such integral optimisation criteria, the RMS values of the current loads in the elastic elements (ropes) of overhead travelling cranes have been used.Conclusions. Such integral criteria are integral functionalities that usually reflect undesirable properties of machines and their mechanisms, thus, they are subject to minimisation","PeriodicalId":377176,"journal":{"name":"51(2022)","volume":"16 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-06-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124113734","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: 1
Isothermal Transformations in High-Strength Cast Iron 高强度铸铁的等温相变
51(2022) Pub Date : 2022-05-26 DOI: 10.54919/2415-8038.2022.51.48-58
R. Hasanli, I. Aliyev, Nizami Poladov, Lala Azimova, T. Tagiyev
{"title":"Isothermal Transformations in High-Strength Cast Iron","authors":"R. Hasanli, I. Aliyev, Nizami Poladov, Lala Azimova, T. Tagiyev","doi":"10.54919/2415-8038.2022.51.48-58","DOIUrl":"https://doi.org/10.54919/2415-8038.2022.51.48-58","url":null,"abstract":"Relevance. The technological process of manufacturing parts from high-strength cast irons is simpler and more economical than the process of manufacturing parts from steel. Cast irons are less sensitive to stress concentrators and strike loads. Spheroidal graphite cast irons can achieve DI 70 grades even in the cast state. Through hardening heat treatment or additional alloying, it is possible to produce cast irons of higher strength (grades DI 80 and above). As the strength properties of cast irons increase, disadvantages in the form of low ductility and plasticity become increasingly apparent. These problems can be compensated by providing an ausferritic, bainite or bainite-austenitic structure of the metal matrix of cast irons. A good solution is to obtain cast irons with a complex structure of the bainite-ausferrite type. In this regard, the relevance of this work is due to the fact that, in the practice of modern mechanical engineering, high-strength cast irons are increasingly used.","PeriodicalId":377176,"journal":{"name":"51(2022)","volume":"253 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-05-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117305928","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: 3
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