Alpha-effect in three-dimensional coherent vortex of conducting rotating liquid

We study one-point statistics of spiral turbulent pulsations on the background of three-dimensional large-scale vortex in a rotating fluid. Assuming that the helical flow is created by a statistically axially symmetric random force with broken mirror symmetry, we analytically calculate velocity-vorticity mean including its magnitude and the anisotropy. For electrically conducting liquid, we examine the $\alpha$-effect in the system. The found elements of $\alpha$-matrix strongly depend on relation between Rossby $\mathrm{Ro}$ and magnetic Prandtl $\mathrm{Pr}_{\mathrm{m}}$ numbers in considered region $\mathrm{Ro}\lesssim 1$, $\mathrm{Pr}_{\mathrm{m}} \lesssim 1$. We establish criterion for the numbers when the $\alpha$-effect leads to instability of large-scale magnetic fieldComment: 16 page

Simulation of a metal vapor active media power supply

The results of the development of the high-frequency metal vapor active media power supply are presented. The results of OrCAD simulation of the processes that occur in the power supply are described. The results of the simulation and experiment for the resistive load operation mode were compare

Application of infrared spectroscopy in combination with chemometric algorithms for determining the presence of styrene-butadiene block copolymer in bitumen products

В настоящее время для улучшения эксплуатационных характеристик асфальтобетонных покрытий широкое распространение получило применение полимерно-битумных вяжущих (ПБВ), в том числе содержащих сополимер стирола с бутадиеном (СБС). Ввиду низкого содержания полимера в составе ПБВ, качественное обнаружение полимера в составе нефтяного битума является непростой исследовательской задачей. Существующие методы обнаружения полимера в нефтяном битуме основаны на сложной многоступенчатой экстракции или на измерении условной характеристической вязкости полимера в анализируемом ПБВ. Данные методы являются трудоемкими и времязатратными, требуют применения ряда специфических органических растворителей и стандартных образцов. В данной работе рассмотрена возможность использования инфракрасной спектроскопии (ИКС) нарушенного полного внутреннего отражения (НПВО) с последующей обработкой спектров с применением хемометрических алгоритмов при исследовании ПБВ, содержащих СБС. Проиллюстрировано применение метода главных компонент (PCA, МГК), а также метода одноклассовой классификации – метода формального независимого моделирования аналогий классов (DD-SIMCA). Применение ИКС в сочетании с хемометрическими методами обработки данных значительно облегчает и ускоряет такую исследовательскую задачу, как установление наличия СБС в битумных продуктах. Цель данной работы состояла в решении классификационной задачи при исследовании битумных продуктов, а именно отнесение / не отнесение битумного продукта к ПБВ с СБС.At present polymer-bitumen binders (PBB), including those containing styrene-butadiene copolymer (SBC), are widely used for improving the performance of asphalt concrete coverings. Qualitative detection of the polymer in the petroleum bitumen composition is a difficult research task owing to the low content of the polymer in the PBB composition. Existing methods for determining the polymer in petroleum bitumen are based on a complex multi-stage extraction or on measuring the specific characteristic viscosity of the polymer in the analyzed PBB. These methods are time-consuming and labor-intensive, and require application of a number of specific organic solvents and reference standards. The present work considers the possibility of applying infrared spectroscopy of disturbed total internal reflection (ATR) with subsequent processing of spectra using chemometric algorithms in the study of PBB containing SBC. Application of the principal component analysis (PCA), as well as one-class classification method, the method of soft independent modeling of class analogy (DD-SIMCA), is illustrated. The use of infrared spectroscopy in combination with chemometric data processing methods greatly simplifies and accelerates the research task of detection SBS in bitumen products. The objective of this work was to solve the classification and identification problem in the course of studying bitumen products, i.e. attributing/non-attributing a bitumen product to PBB with SBS.Автор выражает особую благодарность за оказанную помощь при написании настоящей статьи главному научному сотруднику ФИЦ Химической физики РАН доктору физико-математических наук Родионовой Оксане Евгеньевне.The author is especially grateful to Chief Scientist of the Federal Research Center for Chemical Physics RAS Doctor of Physical and Mathematical Sciences Rodionova Oxana Yevgenievna for help in writing this article

Synthesis of New Bitopic Tetra(pyrazolyl)-Ligands with Neopentane and O-Xylene Backbones

Several new bitopic pyrazole-containing ligands were prepared from the corresponding pyrazoles and tetrahalogen or tetratosyloxy derivatives of o-xylene and neopentane in a superbasic medium (KOH-DMSO)

Spectroscopic study of red-light-emitting centers in K2Al 2B2O7: Fe single crystals

We report on spectroscopic study of red-light-emitting centers in K 2Al2B2O7 (KABO) single crystals containing ca. 2 ppm of Fe3+. Owing to the low Fe3+- concentration, KABO does not show noticeable absorption due to Fe3+ d-d-transitions in the visible spectral region, but it exhibits the charge-transfer (CT) UV-absorption bands O-Fe at 4.7, 5.7 and 6.5 eV. The red photoluminescence at 1.675 eV (FWHM = 0.173 eV) is due to intracenter 4T1 (4G) → 6A1 (6S) transitions in Fe3+ ions. Because of partial overlapping of the fundamental absorption edge of the crystal, where mobile excitons are created, and a broad CT absorption band at 6.5 eV, the most intensive red emission occurs at 7 K upon excitation in the excitonic energy region. The presence of two nonequivalent Al2O7 clusters in KABO lattice provides two different types of red-light-emitting centers in the form of Fe3+ ion occupied the Al3+ tetrahedral site. Superposition of their luminescence bands determines both the spectrum and temperature dependence of red emission in KABO at T = 7-80 K: two bands with the ratio of intensities of ca. 2:1 are 20 meV-shifted relative to each other; two-stage thermal quenching obeys the Mott law with ET = 9 and 20 meV. © 2013 Elsevier B.V. All rights reserved

Operation of a capacitive pumped cubr laser in a reduced energy deposition mode

The results of the operation of a capacitive pumped CuBr laser in a reduced energy deposition mode are presented. A high radiation-pulse repetition rate of 100 kHz in the active medium of copper bromide vapors was obtained. The results of OrCAD simulation of the high-frequency metal vapor active media pumping source with capacitive pumping are presented

Program complex for simulation of kinetics of tunneling electron transfer in organic and inorganic systems

В настоящей работе разработан учебный программный комплекс для моделирования кинетики туннельного переноса электрона в органических и неорганических системах. В данной работе развит математический формализм и выполнено численное моделирование кинетики туннельного переноса электрона в условиях диффузионно-контролируемой подвижности дефектов. Разработанный комплекс будет внедрен в образовательный процесс для проведения практикума по курсу «Моделирование биологических процессов и систем» для студентов, изучающих биомедицинскую инженерию.The present work is devoted to development of laboratory program complex for simulation of tunneling electron transfer in organic and inorganic systems. In the present paper the mathematical formalism was developed and computational modeling of tunneling electron transfer in conditions of diffused-controlled mobility of defects was carried out. The program complex will be implemented for laboratory session of discipline «Modeling of biological processes and systems» for students studying biomedical engineering

EDAC program code for the simulation of photoelectron diffraction

С помощью программного кода EDAC проведено моделирование картин рентгеновской фотоэлектронной дифракции в рамках приближения MSC-SW для поверхности слоистого дихалькогенида lT-TiSe2.X-ray photoelectron diffraction patterns has been simulated by the means of EDAC program code within MSC-SW approximation for the surface of layered dichalcogenide lT-TiSe2

Radiation-stimulated processes in SrMgF4 single crystals irradiated with fast electrons

Large single crystals of SrMgF4 (SMF), grown by the Bridgman method, were studied (T = 7–350 K, E = 1.2–6.2 eV) for both the pristine unirradiated and irradiated by an electron-beam (Ee = 10 MeV, D = 100–160 kGy, Φmax = 5 × 1015 electrons/cm2) SMF-crystals. The optical absorption spectra at different radiation doses were determined. The luminescence spectra were studied upon excitation with visible/ultraviolet light (PL), or X-ray radiation (XRL). The PL excitation (PLE) spectra under UV-radiation, the temperature dependence curves for the luminescence intensity of steady-state XRL and PL recorded monitoring emission at different energies, as well as low-temperature thermoluminescence were studied. The paper discusses the effect of electron-beam irradiation on the optical and luminescence properties of SMF crystals, the temperature dependence of the luminescence intensity and low-temperature thermoluminescence of irradiated SMF crystals. © 2021 Elsevier B.V.Nuclear Physics, NPSiberian Branch, Russian Academy of Sciences, SB RAS, (RFMEFI62119X0022)Ministry of Education and Science of the Russian Federation, Minobrnauka, (FEUZ-2020-0060)Ministry of Education and Science of the Republic of Kazakhstan, (AP08855672)Ural Federal University, UrFUFunding text 1: The work was partially supported by the Ministry of Science and Higher Education of the Russian Federation (through the basic part of the government mandate, project № FEUZ-2020-0060 ), the Science Committee of the Ministry of Education and Science of the Republic of Kazakhstan (Grant № AP08855672 ). All the crystals examined were grown in framework of the state assignment of IGM SB RAS. The X-ray excited measurements were performed at the shared research center SSTRC based on the VEPP-4—VEPP-2000 complex at Budker Institute of Nuclear Physics, Siberian Branch of the Russian Academy of Sciences (Novosibirsk, Russia) using equipment supported by project RFMEFI62119X0022 . The authors are grateful to A.Yu. Sofronova and M.N. Sarychev (UrFU) for assistance with low-temperature measurements.Funding text 2: The work was partially supported by the Ministry of Science and Higher Education of the Russian Federation (through the basic part of the government mandate, project № FEUZ-2020-0060), the Science Committee of the Ministry of Education and Science of the Republic of Kazakhstan (Grant № AP08855672). All the crystals examined were grown in framework of the state assignment of IGM SB RAS. The X-ray excited measurements were performed at the shared research center SSTRC based on the VEPP-4—VEPP-2000 complex at Budker Institute of Nuclear Physics, Siberian Branch of the Russian Academy of Sciences (Novosibirsk, Russia) using equipment supported by project RFMEFI62119X0022. The authors are grateful to A.Yu. Sofronova and M.N. Sarychev (UrFU) for assistance with low-temperature measurements