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Selection of shaped charges parameters for producing aluminum particles with velocities in the range of 2.5-16 km/s

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Defence Technology（防务技术） 2024年第8期38卷 126-135页

作者： vladimir I.Kolpakov Sergey v.fedorov Ekaterina P.vinogradova Irina A.Bolotina Bauman Moscow State Technical University Moscow 105005Russia

Testing rocket and space technology objects in ground conditions for resistance to the impact of meteoroids and fragments of space debris can be carried out using shaped charges. To substantiate the design parameters of shaped charges that ensure the formation of aluminum particles in a wide velocity range(from 2.5 to 16 km/s), numerical modeling of the formation process was carried out within the framework of a two-dimensional axisymmetric problem of continuum mechanics using three different computing codes to increase the reliability of the results. The calculations consider shaped charges with a diameter of 20-100 mm with aluminum liners of various shapes. It is shown that the formation of particles with velocities close to the lower limit of the considered range is ensured by gently sloping segmental liners of degressive thickness. To form higher-velocity particles with velocities over 5 km/s, it is proposed to use combined liners, the jet-forming part of which has the shape of a hemisphere of constant thickness or the shape of a semi-ellipsoid or semi-superellipsoid of rotation of degressive thickness.

关键词： Space debris Meteoric impact Explosion Shaped charge High-velocity aluminum element Segmental liner Combined liner Numerical simulation

Spherically Symmetric Problem of General Relativity for a Fluid Sphere

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Journal of Modern Physics 2024年第4期15卷 401-415页

作者： valery v. vasiliev Leonid v. fedorov Institute of Applied Mechanics of Russian Academy of Sciences Moscow Russia

The paper is devoted to a spherically symmetric problem of General Relativity (GR) for a fluid sphere. The problem is solved within the framework of a special geometry of the Riemannian space induced by gravitation. According to this geometry, the four-dimensional Riemannian space is assumed to be Euclidean with respect to the space coordinates and Riemannian with respect to the time coordinate. Such interpretation of the Riemannian space allows us to obtain complete set of GR equations for the external empty space and the internal spaces for incompressible and compressible perfect fluids. The obtained analytical solution for an incompressible fluid is compared with the Schwarzchild solution. For a sphere consisting of compressible fluid or gas, a numerical solution is presented and discussed.

关键词： General Relativity Spherically Symmetric Problem Fluid Sphere

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单原子活化过硫酸盐降解有机污染物研究进展

工业水处理 2024年第7期44卷 38-46页

作者：赵杰吴俊峰窦艳艳 fedorov svyatoslav vIKTOROvICH 王现丽刘彪朱新锋毛艳丽高宏斌中原工学院能源与环境学院河南郑州450007 河南城建学院河南省水体污染防治与修复重点实验室河南平顶山467036 圣彼得堡国立建筑工程大学环境与市政工程学院俄罗斯圣彼得堡190005

随着工业的迅速发展,含有大量难降解有机污染物的生活生产废水被排入水体,对人体健康与环境产生严重威胁。基于过硫酸盐的高级氧化技术在处理难降解有机废水上有着突出表现,而采用单原子催化剂能最大限度地利用金属原子,减少金属离子溶... 详细信息

随着工业的迅速发展,含有大量难降解有机污染物的生活生产废水被排入水体,对人体健康与环境产生严重威胁。基于过硫酸盐的高级氧化技术在处理难降解有机废水上有着突出表现,而采用单原子催化剂能最大限度地利用金属原子,减少金属离子溶出,在活化过硫酸盐降解有机污染物中有很好的应用前景。综述了单原子催化剂的制备方法,并阐述了各种方法的优缺点。分别论述了Fe、Co、Mn和Cu等金属单原子催化剂活化过硫酸盐降解有机污染物的应用,并总结了单原子催化剂活化过硫酸盐的机理以及单原子催化剂活化过硫酸盐体系对有机污染物的降解机理。最后对单原子催化剂活化过硫酸盐降解有机污染物未来的发展做出了讨论及展望。

关键词：单原子催化剂过硫酸盐有机污染物金属基催化剂

Measurement of yields and angular distributions ofγ-quanta from the interaction of 14.1 Mev neutrons with oxygen,phosphorus,and sulfur

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Chinese Physics C 2024年第3期48卷 79-92页

作者： D.N.Grozdanov N.A.fedorov S.B.Dabylova Yu.N.Kopatch I.N.Ruskov v.R.Skoy T.Yu.Tretyakova C.Hramco P.I.Kharlamov G.v.Pampushik P.G.Filonchik A.v.Andreev Joint Institute for Nuclear Research(JINR) DubnaRussia Institute for Nuclear Research and Nuclear Energy Bulgarian Academy of SciencesSofiaBulgaria Faculty of Physics Lomonosov Moscow State UniversityMoscowRussia L.N.Gumilyov Eurasian National University AstanaKazakhstan Skobeltsyn Institute of Nuclear Physics Moscow State UniversityMoscowRussia Institute of Chemistry of Moldova ChisinauRepublic of Moldova Moscow Institute of Physics and Technology MoscowRussia

A study of the inelastic scattering of neutrons with an energy of 14.1 Mev on the nuclei of oxygen,phosphorus,and sulfur was performed at the TANGRA facility at JINR(Dubna).The experiment aimed to refine existing data and obtain new data on the yields and angular distributions ofγ-quanta emitted by the studied nuclei due to neutron-induced nuclear reactions using the tagged neutron *** types of detector systems were used to registerγ-***γ-ray yields were measured using a high-purity germanium(HPGe)*** angular distributions ofγ-rays were obtained using a system of 18 scintillation detectors based on bismuth germanite Bi_(4)Ge_(3)O_(12)(BGO)located around the *** performed experiments measured the yields of two transitions for the reaction of tagged neutrons with 16O,nine transitions for the reaction with ^(31)P,and nine transitions for the reaction with ^(32)S for the first *** angular anisotropy of theγ-radiation accompanying the inelastic scattering of neutrons with an energy of 14.1 Mev on ^(31)P nuclei was also measured for the first time.

关键词： tagged neutron method yields of gamma-quanta high-resolution gamma-spectrometry neutron-nuclear reactions neutron scattering

Acoustics of a viscoelastic medium with encapsulated bubbles

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Journal of Hydrodynamics 2021年第1期33卷 55-62页

作者： Damir A.Gubaidullin Yuri v.fedorov Laboratory of Continuum Mechanics Institute of Mechanics and EngineeringFRC Kazan Scientific CenterRussian Academy of SciencesKazanRussia

In this paper,a modified Rayleigh-Lamb equation is derived that takes into account the radial vibrations of a gas bubble coated with a viscoelastic shell and located in an elastic *** small oscillations of inclusion,the problem of heat exchange between a gas,a liquid phase,a viscoelastic shell,and an elastic medium is *** energy integral is *** the case of small disturbances,the dispersion relation is found from the Rayleigh-Lamb equations,energy,and the known wave equation for the bubbly *** analytical expression of the equilibrium speed of sound is written out and its dependence on the size of the viscoelastic shell and the disturbance frequency is *** example of a mixture of polydimethylsiloxane with air bubbles coated with a rubber shell illustrates the influence of the elasticity of the carrier medium and the shell of the bubbles on the dependence of the phase velocity and attenuation coefficient on the perturbation *** a mixture of water with air bubbles coated with a rubber shell,the influence of the dependences of the shear modulus and viscosity of butyl rubber on the frequency of disturbances at different temperature on the dispersion curves is shown.A comparison of the theory with experimental data is given.

关键词： Acoustic wave gas bubbles viscoelastic medium and shell shear modulus dispersion equation

Geochemistry and petrology of superpure quartzites from East Sayan Mountains, Russia

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Acta Geochimica 2019年第1期38卷 22-39页

作者： A.M.fedorov v.A.Makrygina A.I.Nepomnyaschikh A.P.Zhaboedov A.v.Parshin v.F.Posokhov Yu.v.Sokolnikova A.P.vinogradov Institute of Geochemistry SB RAS Irkutsk National Research Technical University Irkutsk Scientific Center SB RAS Irkutsk State University Geological Institute SB RAS

Quartzites are widespread within Earth's lithosphere, but their highly pure varieties occur quite infrequently. With the development of alternative energy sources, including solar, and with increasing demand for high-purity quartz for optics, interest has risen in highpurity silicon-bearing materials. The quartzites discovered in the southeast part of the Eastern Sayan Mountains are particularly attractive for exploration in terms of their raw material quality and feasibility to be enriched. For this reason, their genesis also merits study. Available geochemical data show that chemogenic(d^(18)O>29.2%)siliceous-carbonate sediments of the Irkut Formation are fairly pure(impurity elements ved carbonate components of the rock. Bedded quartzites remote from the intrusive granitoids and near-contact quartzites were recognized based on geochemical and petrographic data. Influenced by the Sumsunur granitoids, the near-contact quartzites originally contained >0.9% impurities, but later, under the action of sliding slabs of ophiolite dynamothermal treatment reduced impurities to < 100 ppm, resulting in ‘‘superquartzites' '(highly pure quartzites). The presence of only minor structural impurities is due to the enrichment capacity of superquartzites to 10.1 ppm(7.2 ppm under special conditions) of 10 elements: Fe, Al, Ti, Ca, Mg, Cu,Mn, Na, K, and Li.

关键词： High-purity quartz Superquartzite Gravitational sliding Dynamic metamorphism Recrystallization

Technological monitoring of subgrade construction on high-temperature permafrost

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Research in Cold and Arid Regions 2015年第4期7卷 316-322页

作者： svyatoslav Ya.Lutskiy Taisia v.Shepitko Alexander M.Cherkasov Federal State-Funded Educational Institution of Higher vocational Education Moscow State University of Railway Engineering MGUPS (MIIT)

Three stages of complex technological monitoring for the increase of high-temperature-permafrost soil bearing capacity are described. The feasibility of process monitoring to improve the targeted strength properties of subgrade bases on frozen soils is demonstrated. The rationale for the necessity of predictive modeling of freeze-thaw actions during the subgrade construction period is provided.

关键词： permafrost soils subgrade monitoring bearing capacity complex technology

Adsorption and photo-catalytic properties of layered lepidocrocite-like quasi-amorphous compounds based on modified potassium polytitanates

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Particuology 2014年第6期12卷 22-28页

作者： E.v.Tretyachenko A.v.Gorokhovsky G.Y.Yurkov F.S.fedorov M.A.vikulova D.S.Kovaleva E.E.Orozaliev Department of Chemistry Saratov State Technical University

TiO2 compounds possess relatively high adsorption abilities and exhibit high photocatalytic activities that exhibit potential for the destruction of organic pollutants in natural and waste *** potassium polytitanates modified using transition metals and their oxides/hydroxides generate new nanomaterials that operate in the visible spectral *** study presents the synthesis and investigation of the structure,composition and photocatalytic activity of powdered nanoscale quasi-amorphous potassium polytitanates particles modified with iron,zinc,copper,cobalt and nickel sulfate in aqueous *** of the powders investigated in this work exhibit a high adsorption capacity for methylene blue dye（15-20mg/g） related to the welldeveloped surface of the layered potassium polytitanate *** transition metals and their oxides/hydroxides influences the electronic structure of the obtained systems.A high photocatalytic activity was observed for systems containing iron,zinc,nickel and their oxides/hydroxides in the ultraviolet and visible ranges.

关键词： Layered potassium titanate Chemical modification Heterostructured particles Photocatalytic activity Adsorption

Composite technology of earthwork construction on taliks in cryolithic zones

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Research in Cold and Arid Regions 2013年第5期5卷 577-581页

作者： svyatoslav Ya.Lutskiy Taisiya v.Shepitko Alexander M.Cherkasov Federal State-Funded Educational Institution of Higher vocational Education Moscow State University of Railway Engineering (MGUPS (MIIT)) Institute of Rail Track Construction and Structures Permafrost Research Laboratory Federal State-Funded Educational Institution of Higher Vocational EducationMoscow State University of Railway Engineering (MGUPS (MIIT))

This paper reviews construction and technological solutions for roadbeds in talik areas of permafrost soil, and proposes an integrated technology for prevention and elimination of taliks during construction periods. It also summarizes the expe- rience of process regulation scheduling and soil conditions monitoring during construction.

关键词： integrated technology permafrost soil taliks technological adjustment