Technical Physics Letters最新文献

{"title":"Electronic Spectroscopy of Graphene Obtained by Ultrasonic Dispersion","authors":"A. G. Kastsova, N. V. Glebova, A. A. Nechitailov, A. O. Krasnova, A. O. Pelageikina, I. A. Eliseyev","doi":"10.1134/s1063785023900297","DOIUrl":"https://doi.org/10.1134/s1063785023900297","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>A technology for obtaining graphene by means of ultrasonic dispersion of thermally expanded graphite in the presence of a surface-active polymer Nation is presented. The technology makes it possible to obtain large amounts of low-layer (1–3 layers) graphene in a relatively short time. An approach to control the dispersion process based on UV spectroscopy of dispersions is described. A mechanism is proposed for the effect of a surface-active polymer on the production of low-layer graphene by ultrasonic dispersion.</p>","PeriodicalId":784,"journal":{"name":"Technical Physics Letters","volume":null,"pages":null},"PeriodicalIF":0.6,"publicationDate":"2024-03-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140125348","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Modeling of the Interstellar Medium Optical Absorption Spectrum by Primitive Hybrid Molecules C24H30, C32H36, and C73H74","authors":"M. S. Chekulaev, S. G. Yastrebov","doi":"10.1134/s1063785023900121","DOIUrl":"https://doi.org/10.1134/s1063785023900121","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>Accounting for the different contributions of the aromatic rings, separated with <i>sp</i>³ bonds, with ab initio method we constructed the hybrid cluster C₇₃H₇₄ which UV spectrum matches the most noticeable absorption band of 217.5 nm, known from astrophysical observations.</p>","PeriodicalId":784,"journal":{"name":"Technical Physics Letters","volume":null,"pages":null},"PeriodicalIF":0.6,"publicationDate":"2024-03-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140125361","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Electrochemical Performance of LIB Anodes Based on Silicon Monoxide: The Effect of Disproportionation and Treatment in HF","authors":"A. A. Grushina, D. A. Lozhkina, A. A. Krasilin, A. M. Rumyantsev, E. V. Astrova","doi":"10.1134/s1063785023900248","DOIUrl":"https://doi.org/10.1134/s1063785023900248","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>Composite SiO/C anodes for lithium-ion batteries (LIB) obtained by carbonization of silicon monoxide with fluorocarbon were investigated. Preliminary modification of the initial silicon monoxide was carried out by disproportionation and subsequent treatment in hydrofluoric acid. The study of the elemental composition of modified SiO and the electrochemical performance of composite anodes made from it showed that the oxygen content in the oxide matrix played a decisive role in changing their behavior. Depletion of it with oxygen as a result of treatment in HF had a beneficial effect, leading to higher stability of the electrodes during cycling, an increase in their capacity, coulombic efficiency and rate capability.</p>","PeriodicalId":784,"journal":{"name":"Technical Physics Letters","volume":null,"pages":null},"PeriodicalIF":0.6,"publicationDate":"2024-03-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140125578","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Obtaining Anisotypic Heterostructures for a GaSb-Based Photovoltaic Converter Due to Solid-Phase Substitution Reactions","authors":"G. S. Gagis, V. I. Kuchinskii, D. Yu. Kazantsev, B. Ya. Ber, M. V. Tokarev, V. P. Khvostikov, M. V. Nakhimovich, A. S. Vlasov, V. I. Vasil’ev","doi":"10.1134/s1063785023900170","DOIUrl":"https://doi.org/10.1134/s1063785023900170","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>The possibility of manufacturing photovoltaic converter structures due to solid-phase reactions of substitution of Sb atoms in GaSb semiconductor wafers with As or P atoms, with simultaneous diffusion of Zn, is demonstrated.</p>","PeriodicalId":784,"journal":{"name":"Technical Physics Letters","volume":null,"pages":null},"PeriodicalIF":0.6,"publicationDate":"2024-03-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140883710","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The Ion–Solid Interaction Potential Determination from the Backscattered Particles Spectra","authors":"P. Yu. Babenko, A. N. Zinoviev, V. S. Mikhailov, D. S. Tensin, A. P. Shergin","doi":"10.1134/s1063785023900030","DOIUrl":"https://doi.org/10.1134/s1063785023900030","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>The values of the atomic particle–solid potential were obtained for the first time from experimental data on the energy spectra and angular dependences of backscattered particles. The proposed procedure for determining the potential has never been applied previously. It is shown that the obtained data do not depend on the potential approximation used. The ion–solid interaction potential differs markedly from the potential describing collisions in the gas phase. The screening constant increases by 10–15%. The increase in screening is due to an increase in the density of the electron gas in the region between the incident particle and scattering center.</p>","PeriodicalId":784,"journal":{"name":"Technical Physics Letters","volume":null,"pages":null},"PeriodicalIF":0.6,"publicationDate":"2024-03-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140125289","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Fully Three-Dimensional Coupled Simulation of Flame Propagation through a Polymer under the Action of a Heat Flux","authors":"S. A. Trubachev, O. P. Korobeinichev, A. A. Shaklein, A. R. Sagitov, I. V. Kulikov, E. A. Sosnin","doi":"10.1134/s1063785024700172","DOIUrl":"https://doi.org/10.1134/s1063785024700172","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>The paper presents a fully three-dimensional coupled simulation of flame propagation through epoxy resins reinforced with glass fiber (glass–epoxy) under the action of a heat flux from two sides, using the Fire Dynamic Simulator package. The model includes three-dimensional heat and mass transfer, diffusion of basic substances in the gas phase, and diffusion transport of pyrolysis products in the solid phase. The pyrolysis and oxidation processes are represented by macroreactions and take into account the effect of the phosphorus-containing flame retardant DDM-DOPO. The model satisfactorily predicts the experimentally observed dynamics of flame propagation.</p>","PeriodicalId":784,"journal":{"name":"Technical Physics Letters","volume":null,"pages":null},"PeriodicalIF":0.6,"publicationDate":"2024-03-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140044785","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Modeling of Transformations during the Formation of Local Waves of SARS-CoV-2 Spreading at the Endemic Stage of the Pandemic","authors":"A. Yu. Perevaryukha","doi":"10.1134/s1063785023700153","DOIUrl":"https://doi.org/10.1134/s1063785023700153","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>Most of the predictions made by the author at the end of 2022 about the development of scenarios for the coronavirus epidemic at the beginning of 2024 have been confirmed. There is a fungible set of changing SARS-CoV-2 strains, among which there is no longer a leader. In Asian countries, in December 2023, regional outbreaks of morbidity due to strains from a new branch of Omicron, BA.2.86, began, just like a year ago, although, in the summer between waves, the incidence of COVID-19 was low. The predicted nonlocal COVID outbreak is a positive feedback loop: the more infections, the higher the likelihood of further mutations in the virus and the greater chances of strains evading antibodies. It has been confirmed by a number of studies that repeated COVID often causes long-term and severe immunosuppression. The factor of post-COVID immunodeficiency and T-cell depletion in susceptible groups maintains a reservoir for the accumulation of SARS-CoV-2 mutations. This specific phenomenon was not taken into account in model predictions a year ago. The concept of the SIRS model is not applicable to SARS-CoV-2. Omicron’s many branches make it difficult to create a new vaccine. Antigenic drift makes it possible to bypass vaccine immunity, but global outbreaks are not observed for a long time due to the persistence of cytotoxic CD8+ T cells in us. From a dynamic point of view, the COVID-19 pandemic is divided into clusters of regional epidemics and demonstrates oscillatory dynamics. The oscillations have changed their character, with the wave crests becoming longer, although smaller in amplitude. Epidemic waves do not develop so rapidly, but grow gradually; however, this only increases the final number of cases. The damped amplitude of the waves of infection that formed after the initial outbreak again turns into an extreme peak. This may be due to effects after crisis events: mass infections or an increase in virulence of a new strain that evades the antibodies of vaccine immunity, but is destroyable. The two situations are different. We classified the observed local epidemic scenarios of COVID waves according to the types of oscillations from a physical point of view. COVID waves are no longer classic decaying relaxation oscillations. Using simulation modeling, we analyzed variants of epidemic dynamics with sharp changes. Special epidemic scenarios of the sudden occurrence of a short wave as a probable development of the current situation in 2024 were studied on the basis of nonlinear equations with a deviating argument. The COVID wave of the JN.1 strain in winter 2024 is the second fastest growing in cases of severe disease after the Omicron BA.1 wave in spring 2022 and will inevitably lead to a new impulse round in the evolution of the coronavirus.</p>","PeriodicalId":784,"journal":{"name":"Technical Physics Letters","volume":null,"pages":null},"PeriodicalIF":0.6,"publicationDate":"2024-02-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139770525","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Mathematical Modeling of Propagation and Diffraction of Microwaves in Anisotropic Magnetic Nanocomposites and 3D Nanostructures Based on Opal Matrices","authors":"G. S. Makeeva","doi":"10.1134/s1063785023700141","DOIUrl":"https://doi.org/10.1134/s1063785023700141","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>A computational algorithm for solving the boundary value problem of diffraction has been developed for Maxwell’s equations together with the Landau‒Lifshitz equation using the Galerkin projection method. Using the developed computational algorithm for calculating the conductivity matrix of an autonomous block with Floquet channels (FABs), the real and imaginary parts of the complex wavenumber of a quasi-extraordinary wave have been calculated from the solution of the characteristic equation depending on the bias field strength. Using the computational algorithm of the multilevel FAB recomposition, the mathematical modeling of diffraction of the fundamental wave on a 3D magnetic nanostructure in a rectangular waveguide has been carried out and the results obtained have been compared with the experiment.</p>","PeriodicalId":784,"journal":{"name":"Technical Physics Letters","volume":null,"pages":null},"PeriodicalIF":0.6,"publicationDate":"2024-01-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139649144","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Segregation of Antimony along the Cross Section of Lead Castings as a Cause of Defects in Isostatic Pressing of Lead Alloy Products","authors":"A. A. Berdychenko, S. G. Ivanov, M. A. Guryev","doi":"10.1134/s1063785023700128","DOIUrl":"https://doi.org/10.1134/s1063785023700128","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>A comparative analysis of the macro- and microstructure of a lead casting and a lead rod obtained from it by isostatic pressing is reported. The effect of segregation of antimony as the main dopant of the investigated alloy on the quality of a product has been demonstrated using advanced nonferrous optical metallography methods. It has been established that the upper part of a casting with a surface crack caused by adding the crystallized casting with lead contains an increased amount of antimony, nonmetallic inclusions, and pores on the fusion surface. Inside the casting, there is a shrinkage cavity along the casting axis, which results from shrinkage of the material during its crystallization. The content of the main element of the alloy (antimony) in lead of the castings corresponds to the PbSb_0.9 alloy according to <i>GOST</i> (State Standard) 1292-81 “Lead‒antimony alloys. Specifications,” but the impurity content exceeds the value recommended by <i>GOST</i> the total impurity content is limited to 0.1%, while the total content of copper, cadmium, bismuth, and palladium in the investigated castings is ~1%. The casting microstructure investigations have shown that the main structural defect is a shrinkage cavity located along the casting axis. The occurrence of this cavity is related to an excessively high temperature of lead casting into a mold. This has led to a long crystallization time, as evidenced by the antimony segregation in the surface areas of the shrinkage cavity. The metal of the surface layers of the shrinkage cavity is characterized by the increased antimony contents, nonmetallic inclusions, and discontinuities, which significantly changes its mechanical properties as compared with the base metal, including the plasticity, which plays a decisive role in the plastic strain processing of the casting.</p>","PeriodicalId":784,"journal":{"name":"Technical Physics Letters","volume":null,"pages":null},"PeriodicalIF":0.6,"publicationDate":"2023-12-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139063583","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Hydrothermal Synthesis of High-Efficiency Carbon Sorbent Based on Renewable Resources","authors":"A. E. Burakov, T. S. Kuznetsova, I. V. Burakova, O. A. Ananyeva, E. S. Mkrtchyan, T. P. Dyachkova, A. G. Tkachev","doi":"10.1134/s106378502370013x","DOIUrl":"https://doi.org/10.1134/s106378502370013x","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>A technique of synthesis of new sorption materials by hydrothermal carbonization of sunflower meal (HTS) with the addition of graphene oxide (GO) and subsequent carbonization (C) has been developed. To assess morphological and phase changes during carbonization, the materials have been characterized by scanning electron microscopy and IR spectroscopy. According to the results obtained, carbonization facilitates the development of latent porosity and reduces the amount of oxygen-containing and alkyl groups. Kinetic sorption studies have also been carried out by the example of extraction of Pb²⁺ ions and organic dye molecules (methylene blue (MB)). The experimental results show that the adsorption capacities of the HTS, HTS/C, HTS/GO, and HTS/GO/C composites were 82.9, 108.6, 168.9, and 148.3 mg/g, respectively, for extraction of Pb²⁺ ions and 1481.8, 1601.1, 1920.3, and 2283 mg/g, respectively, for extraction of MB molecules. It is established that, during the absorption of MB molecules, carbonization affects significantly the contact time. Carbonized samples exhibit high sorption activity, which results in the equilibrium contact time of 15 min (this value is 60 min for noncarbonized samples). The equilibrium time during the adsorption of Pb²⁺ ions is 60 min for all samples. The adsorption kinetics is described using the following models: the pseudo-first-order model, pseudo-second-order model, Elovich model, and intraparticle diffusion model. It is found that the adsorption process is limited by the chemical-exchange reaction and runs in a mixed-diffusion mode.</p>","PeriodicalId":784,"journal":{"name":"Technical Physics Letters","volume":null,"pages":null},"PeriodicalIF":0.6,"publicationDate":"2023-12-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139063306","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}