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Доклады Российской академии наук. Физика, технические науки最新文献

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Mathematical theory of epidemics and pandemics based on the laws of chain and thermal explosions 基于连锁爆炸和热爆炸定律的流行病和大流行病数学理论
Доклады Российской академии наук. Физика, технические науки Pub Date : 2024-08-10 DOI: 10.31857/s2686740024010061
A. A. Philippov
{"title":"Mathematical theory of epidemics and pandemics based on the laws of chain and thermal explosions","authors":"A. A. Philippov","doi":"10.31857/s2686740024010061","DOIUrl":"https://doi.org/10.31857/s2686740024010061","url":null,"abstract":"The article presents a theory of the spread of the virus, including epidemics and pandemics, based on the theories of chain and thermal explosions, where two parameters were introduced to simulate the spread of the virus in an isolated community of people. A model of a community in the form of a multilayered bulb is proposed, in which the infection process proceeds in layers. The formulas obtained correlate with good accuracy with statistical data on the spread of the virus at stable stages of the pandemic. The validity of the model is confirmed by a combination of the formulas obtained, with a number of simplifications, with the formulas of the chain explosion theory and others. The presented theory is in qualitative agreement with empirical theories – SIR, SIRS and others. \u0000The model may be interesting for epidemiology and exact science, since formulas with new parameters may be in demand for modeling phenomena in other areas of nature. The article shows the connection between the theories of chain and thermal explosions.","PeriodicalId":209009,"journal":{"name":"Доклады Российской академии наук. Физика, технические науки","volume":"2 3","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-08-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141920862","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
Cladding-pumped bismuth-doped fiber lasers operating at a wavelength region of 1.4–1.5 µm 工作波长为 1.4-1.5 微米的包层泵浦掺铋光纤激光器
Доклады Российской академии наук. Физика, технические науки Pub Date : 2024-08-10 DOI: 10.31857/s2686740024010014
A. Vakhrushev, A. Kharakhordin, S. Alyshev, A. Khegai, E. Firstova, M. Melkumov, S. Firstov
{"title":"Cladding-pumped bismuth-doped fiber lasers operating at a wavelength region of 1.4–1.5 µm","authors":"A. Vakhrushev, A. Kharakhordin, S. Alyshev, A. Khegai, E. Firstova, M. Melkumov, S. Firstov","doi":"10.31857/s2686740024010014","DOIUrl":"https://doi.org/10.31857/s2686740024010014","url":null,"abstract":"This article reports the results on development and study of the output characteristics of bismuth-doped fiber lasers for the near-IR range, which are pumped into a cladding using multimode laser diodes emitting at a wavelength of 808 nm. The active medium of such lasers was bismuth-doped germanosilicate glass fibers with various shapes (circular and square sections) of the inner cladding coated with a polymer having a refractive index of 1.396. On the basis of such fibers, a series of lasers generating radiation in the wavelength range 1.4–1.5 μm was developed, and their spectral and power characteristics were studied. Numerical simulation was also carried out aimed at finding the optimal configuration of such lasers in order to determine the maximum achievable characteristics of these devices. A good agreement between the calculated data and the experimental results has been obtained. As a result, using a bismuth-doped active fiber with a square cross section of ~80 μm and a core diameter of ~11 μm, a fiber laser was created that operated at a wavelength of ~1460 nm, with a slope efficiency of about 5% and a maximum output power of more than 250 mW.","PeriodicalId":209009,"journal":{"name":"Доклады Российской академии наук. Физика, технические науки","volume":"8 3","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-08-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141920632","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
On giant amplification of effects of phonon nonspecular reflection at a solitary interface between magnetic and non-magnetic media 论磁性介质与非磁性介质孤界面声子非镜反射效应的巨幅放大
Доклады Российской академии наук. Физика, технические науки Pub Date : 2024-08-10 DOI: 10.31857/s2686740024010138
Yu. V. Gulyaev, O. S. Sukhorukova, A. Tarasenko, S. V. Tarasenko, V. Shavrov
{"title":"On giant amplification of effects of phonon nonspecular reflection at a solitary interface between magnetic and non-magnetic media","authors":"Yu. V. Gulyaev, O. S. Sukhorukova, A. Tarasenko, S. V. Tarasenko, V. Shavrov","doi":"10.31857/s2686740024010138","DOIUrl":"https://doi.org/10.31857/s2686740024010138","url":null,"abstract":"On the secluded interface of semi-infinite magnetic and non-magnetic media, hybridiza-tion of magnetoelastic interaction with inhomogeneous exchange or magneto-dipole interaction can lead to the formation of symmetry-protected bound states in the radiation spectrum of the leaky surface magnon polarons. If a quasi-plane bulk elastic wave falls on the surface of a magnetic medium from outside, and the wave parameters approach to the parameters of the surface “dark” state of the above mentioned type, the nonspecular reflection effects of the first order increase unrestrictedly (in the non-dissipative approximation).","PeriodicalId":209009,"journal":{"name":"Доклады Российской академии наук. Физика, технические науки","volume":"2 6","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-08-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141920174","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
Perovskite-based solar cell in tamm plasmon-polariton structure 基于钽质子-极化子结构的过氧化物基太阳能电池
Доклады Российской академии наук. Физика, технические науки Pub Date : 2024-08-10 DOI: 10.31857/s2686740024010042
D. Pykhtin, R. G. Bikbaev, I. V. Timofeev, S. Vetrov, V. F. Shabanov
{"title":"Perovskite-based solar cell in tamm plasmon-polariton structure","authors":"D. Pykhtin, R. G. Bikbaev, I. V. Timofeev, S. Vetrov, V. F. Shabanov","doi":"10.31857/s2686740024010042","DOIUrl":"https://doi.org/10.31857/s2686740024010042","url":null,"abstract":"The spectral properties of a solar cell with a photosensitive perovskite layer in a structure with a Tamm plasmon polariton localized at the boundary of a gold nanolattice and a one-dimensional photonic crystal are investigated. The influence of the parameters of the golden lattice on the surface current density and the efficiency of the proposed device is investigated. It is shown that when an aluminum substrate is replaced with a photonic crystal, a Tamm plasmon polariton is excited, which provides an increase in the surface current density by 33.7%, and efficiency by 35.1%.","PeriodicalId":209009,"journal":{"name":"Доклады Российской академии наук. Физика, технические науки","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-08-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141920847","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
Ice rheology exploration based on numerical simulation of low-speed impact 基于低速冲击数值模拟的冰流变学探索
Доклады Российской академии наук. Физика, технические науки Pub Date : 2024-08-10 DOI: 10.31857/s2686740024010033
I. B. Petrov, E. K. Guseva, V. I. Golubev, V. P. Epifanov
{"title":"Ice rheology exploration based on numerical simulation of low-speed impact","authors":"I. B. Petrov, E. K. Guseva, V. I. Golubev, V. P. Epifanov","doi":"10.31857/s2686740024010033","DOIUrl":"https://doi.org/10.31857/s2686740024010033","url":null,"abstract":"Ice is a complex heterogeneous medium. Its behavior depends on many factors and changes in different processes. Thus, the problem of the determination of the correct rheological model is still unsolved. In this work low-speed impact on ice by the ball striker is considered. The main focus of the research is the development of the method of the correct model selection based on the computer simulation of the laboratory experiment. The simulation was conducted using the following rheology models: isotropic linear elasticity model, elastoplasticity model with the von Mises and the von Mises-Schleicher yield criteria, elasticity model with elastoplastic inclusion. The governing system of equations is solved using grid-characteristic method. Models’ comparison is performed based on the ball’s velocity and depth of ball’s immersion into the ice. The model parameters’ influence on the results is surveyed. As a result, the parameters that reconstruct the solution close to the experimental results are chosen.","PeriodicalId":209009,"journal":{"name":"Доклады Российской академии наук. Физика, технические науки","volume":"6 6","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-08-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141921140","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
Self-oscillating mode in an anomalous thermoviscous liquid flow 反常热粘液体流中的自振荡模式
Доклады Российской академии наук. Физика, технические науки Pub Date : 2024-08-10 DOI: 10.31857/s2686740024010101
V. Kireev, A. A. Mukhutdinova, S. Urmancheev
{"title":"Self-oscillating mode in an anomalous thermoviscous liquid flow","authors":"V. Kireev, A. A. Mukhutdinova, S. Urmancheev","doi":"10.31857/s2686740024010101","DOIUrl":"https://doi.org/10.31857/s2686740024010101","url":null,"abstract":"It is known that the flow of liquids with a nonmonotonic dependence of viscosity on temperature (abnormally thermoviscous liquids) in the presence of temperature gradients, for example, when a heated liquid flows into a cooled channel, is accompanied by the formation of a high-viscosity region localized in the flow, which determines the features of its flow. In this paper, the conditions for the occurrence of self-oscillating regimes of flow rate variation during the flow of anomalously thermoviscous liquids in annular channels under the action of a constant pressure drop and under given conditions of heat transfer on the inner and outer walls of the annular channel are determined. It has been found that self-oscillations in the flow rate of an anomalously thermoviscous liquid can occur when flowing in an annular channel, on the walls of which there is an abrupt decrease in the intensity of heat transfer. The region of existence of the self-oscillation mode is determined by the values of the pressure drop and the geometric parameter equal to the ratio of the width of the annular gap to the radius of the inner cylinder. In addition, weakly damped flow rate oscillations with a very small damping decrement were also observed at the boundaries of this region.","PeriodicalId":209009,"journal":{"name":"Доклады Российской академии наук. Физика, технические науки","volume":"11 6","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-08-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141921351","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
Increasing the efficiency of the use of the energy of a steam explosion in the processing of lignin-cellulose raw materials 提高木质素-纤维素原料加工过程中蒸汽爆炸能量的使用效率
Доклады Российской академии наук. Физика, технические науки Pub Date : 2024-08-10 DOI: 10.31857/s2686740024010128
I. N. Grishnyaev
{"title":"Increasing the efficiency of the use of the energy of a steam explosion in the processing of lignin-cellulose raw materials","authors":"I. N. Grishnyaev","doi":"10.31857/s2686740024010128","DOIUrl":"https://doi.org/10.31857/s2686740024010128","url":null,"abstract":"An analysis was made of the physical processes occurring during a steam explosion and the exit from the reactor of a stream containing lignocellulosic raw materials and a vapor-liquid medium. It is shown that it is necessary to install a Laval nozzle at the reactor outlet. By selecting the design parameters of the reactor and the Laval nozzle, it is possible to ensure the occurrence of a self-oscillating mode of the vapor-liquid medium in the expanding part of the nozzle. Lignocellulosic raw materials passing through the emerging shocks is subjected to additional impact, which leads to its destruction, an increase in the specific surface area, and, consequently, to an increase in reactivity.","PeriodicalId":209009,"journal":{"name":"Доклады Российской академии наук. Физика, технические науки","volume":"2 6","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-08-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141919406","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
Increasing the efficiency of the use of the energy of a steam explosion in the processing of lignin-cellulose raw materials 提高木质素-纤维素原料加工过程中蒸汽爆炸能量的使用效率
Доклады Российской академии наук. Физика, технические науки Pub Date : 2024-08-10 DOI: 10.31857/s2686740024010128
I. N. Grishnyaev
{"title":"Increasing the efficiency of the use of the energy of a steam explosion in the processing of lignin-cellulose raw materials","authors":"I. N. Grishnyaev","doi":"10.31857/s2686740024010128","DOIUrl":"https://doi.org/10.31857/s2686740024010128","url":null,"abstract":"An analysis was made of the physical processes occurring during a steam explosion and the exit from the reactor of a stream containing lignocellulosic raw materials and a vapor-liquid medium. It is shown that it is necessary to install a Laval nozzle at the reactor outlet. By selecting the design parameters of the reactor and the Laval nozzle, it is possible to ensure the occurrence of a self-oscillating mode of the vapor-liquid medium in the expanding part of the nozzle. Lignocellulosic raw materials passing through the emerging shocks is subjected to additional impact, which leads to its destruction, an increase in the specific surface area, and, consequently, to an increase in reactivity.","PeriodicalId":209009,"journal":{"name":"Доклады Российской академии наук. Физика, технические науки","volume":"9 9","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-08-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141919860","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 residual magnetization corrosion of steel samples 残余磁化对钢样品腐蚀的影响
Доклады Российской академии наук. Физика, технические науки Pub Date : 2024-08-10 DOI: 10.31857/s2686740024010078
S. Yakupov, R. R. Kantyukov, G. G. Gumarov, N. Yakupov
{"title":"Effect of residual magnetization corrosion of steel samples","authors":"S. Yakupov, R. R. Kantyukov, G. G. Gumarov, N. Yakupov","doi":"10.31857/s2686740024010078","DOIUrl":"https://doi.org/10.31857/s2686740024010078","url":null,"abstract":"The results of experimental studies of the effect of residual magnetization on the corrosion of steel samples in an aqueous medium are presented. Algorithms of research and processing of results are described. Three cases of initial magnetization of samples are considered. It is established that before the critical magnetization of steel samples, the corrosion wear in the aqueous medium decreases, and then begins to grow. The discovered effect is of great theoretical importance in studying the phenomenon of corrosion, taking into account the initial residual magnetization, as well as of great practical importance, in particular, in the design and operation of various structures and structures made of steel to protect them from corrosion destruction.","PeriodicalId":209009,"journal":{"name":"Доклады Российской академии наук. Физика, технические науки","volume":"8 10","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-08-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141920625","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 rare-earth ion local anisotropy on macroscopic magnetic properties of (La0.985Ho0.015)3Ga5SiO14 lagnasite 稀土离子局部各向异性对 (La0.985Ho0.015)3Ga5SiO14 辉绿岩宏观磁性能的影响
Доклады Российской академии наук. Физика, технические науки Pub Date : 2024-08-10 DOI: 10.31857/s2686740024010056
A. Tikhanovskii, V. Ivanov, A. M. Kuzmenko, A. Mukhin
{"title":"Effect of rare-earth ion local anisotropy on macroscopic magnetic properties of (La0.985Ho0.015)3Ga5SiO14 lagnasite","authors":"A. Tikhanovskii, V. Ivanov, A. M. Kuzmenko, A. Mukhin","doi":"10.31857/s2686740024010056","DOIUrl":"https://doi.org/10.31857/s2686740024010056","url":null,"abstract":"Experimental and theoretical studies of the magnetic properties of the unique Ising-like paramagnet (La0.985Ho0.015)3Ga5SiO14 have been carried out. We found magnetic anisotropy in strong magnetic field (up to 5 T) rotated in the ab*, b*c and ac planes at low temperatures (T ≤ 5K). We show that the observed magnetization features are connected with the local orientation and distribution of the Ho3+ Ising axes, which may deviate from the symmetry-allowed directions due to Ga/Si random filling in the local environment of the magnetic ions.","PeriodicalId":209009,"journal":{"name":"Доклады Российской академии наук. Физика, технические науки","volume":"6 4","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-08-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141920767","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
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