Search

Your search keyword '"Ivanov, V. E."' showing total 388 results
Start Over Author "Ivanov, V. E."
388 results on '"Ivanov, V. E."'

1. Effect of the NO concentration on the ratio I₅₅₇.₇/I₄₂₇.₈ in auroras

Author

Ivanov V. E. and Dashkevich Z. V.

Subjects
nitric oxide, 557.7 nm and 427.8 nm emissions, intensity ratio, aurora, modeling, electron precipitation, Astrophysics, QB460-466
Abstract

We have examined the effect of the nitrogen oxide concentration on the ratio between λ557.7 nm and λ427.8 nm emission intensities in auroras caused by precipitating electron fluxes, using the numerical simulation method. The ratio I₅₅₇.₇/I₄₂₇.₈ has been shown to strongly depend on the NO concentration: the ratio decreases from 7 to 2 with increasing NO maximum concentration at the height profile from 10⁷ to 3·10⁹. This fact is in satisfactory agreement with experimental data.The effect of nitric oxide on the ratio has been demonstrated to occur through the excitation channel of the emission λ557.7 nm, namely, the dissociative recombination of the molecular oxygen ion O⁺₂+eₜₕ due to the ion deactivation by collision reaction with nitric oxide O⁺₂+NO.

Published
2024
Full Text
View/download PDF

8. Diagnostics of emission intensities and electron density in auroras based on empirical precipitation models

Author

Dashkevich Z. V. and Ivanov V. E.

Subjects
auroras, electron precipitation, excitation efficiency, auroral emissions, electron density, planetary distribution, Astrophysics, QB460-466
Abstract

We have studied the influence of the precipitating electron spectrum shape on the integral intensity of emissions λ391.4 nm 1NG N⁺₂, λ670.4 mn 1PG N₂, λ337.1 nm 2PG N₂, λ320.0 nm VK N₂, λ127.3 nm LBH N₂, atomic oxygen emissions λ557.7 and λ630.0 nm, total electron content in the vertical column of aurora. The integral characteristics of the emission intensity and the total electron content are shown to weakly depend on the energy spectrum shape and to be determined mainly by average energy values Eev and energy flux value Fᴇ of precipitating electrons. An algorithm is proposed for diagnosing the planetary distribution of emission intensities and total electron content in auroras based on data from empirical electron precipitation models, without making a priori assumptions about the shape of the energy spectrum of precipitating electrons.

Published
2022
Full Text
View/download PDF

13. The Effect of High-Intensity Electron Beam on the Crystal Structure, Phase Composition, and Properties of Al–Si Alloys with Different Silicon Content

Author

D. V. Zaguliaev, S. V. Konovalov, Yu. F. Ivanov, V. E. Gromov, V. V. Shlyarov, and Yu. A. Rubannikova

Subjects
cast aluminium alloys, electron beam treatment, microstructure, mechanical properties, structure and phase transformations, scanning electron microscopy, transmission electron microscopy, microhardness, tribological testing, Physics, QC1-999
Abstract

The study deals with the element–phase composition, microstructure evolution, crystal-lattice parameter, and microdistortions as well as the size of the coherent scattering region in the Al–10.65Si–2.11Cu and Al–5.39Si–1.33Cu alloys irradiated with the high-intensity electron beam. As revealed by the methods of x-ray phase analysis, the principal phases in untreated alloys are the aluminium-based solid solution, silicon, intermetallics, and Fe2Al9Si2 phase. In addition, the Cu9Al4 phase is detected in Al–10.65Si–2.11Cu alloy. Processing alloys with the pulsed electron beam induces the transformation of lattice parameters of Al–10.65Si–2.11Cu (aluminium-based solid solution) and Al–5.39Si–1.33Cu (Al1 and Al2 phases). The reason for the crystal-lattice parameter change in the Al–10.65Si–2.11Cu and Al–5.39Si–1.33Cu alloys is suggested to be the changing concentration of alloying elements in the solid solution of these phases. As established, if a density of electron beam is of 30 and 50 J/cm2, the silicon and intermetallic compounds dissolve in the modified layer. The state-of-the-art methods of the physical materials science made possible to establish the formation of a layer with a nanocrystalline structure of the cell-type crystallization because of the material surface irradiation. The thickness of a modified layer depends on the parameters of the electron-beam treatment and reaches maximum of 90 µm at the energy density of 50 J/cm2. According to the transmission (TEM) and scanning (SEM) electron microscopy data, the silicon particles occupy the cell boundaries. Such changes in the structural and phase states of the materials response on their mechanical characteristics. To characterize the surface properties, the microhardness, wear parameter, and friction coefficient values are determined directly on the irradiated surface for all modification variants. As shown, the irradiation of the material surface with an intensive electron beam increases wear resistance and microhardness of the Al–10.65Si–2.11Cu and Al–5.39Si–1.33Cu alloys.

Published
2021
Full Text
View/download PDF

15. Change in Structural-Phase States and Properties of Lengthy Rails during Extremely Long-Term Operation

Author

V. E. Gromov, Yu. F. Ivanov, V. E. Kormyshev, A. A. Yuriev, A. P. Semin, Yu. A. Rubannikova

Subjects
rails, micro-nanocrystalline structure, lamellar pearlite, long operation, mechanisms of hardening, Physics, QC1-999
Abstract

The regularities and formation mechanisms of structural-phase states and properties at different depths in the rail heads along the central axis and fillet after differential quenching of 100-meter rails and extremely long operation (with passed tonnage of 1411 million tons gross weight) have been revealed by the methods of the state-of-the-art physical materials science. As revealed, the differential quenching is accompanied by the formation of morphologically multi-aspect structure presented by grains of lamellar perlite, ferrite–carbide mixture, and structure-free ferrite. The steel structure is characterized by the α-Fe lattice parameter, the level of microstresses, the size of coherent-scattering region, the value of interlamellar distance, the scalar and excess dislocation densities. As shown, the extremely long operation of rails is accompanied by the numerous transformations of metal structure of rail head: firstly, a fracture of lamellar pearlite structure and a formation of subgrain structure of submicron (100–150 nm) sizes in the bulk of pearlite colonies; secondly, a precipitation of carbide phase particles of nanometer range along the boundaries and in the bulk of subgrains; thirdly, a microdistortion growth of steel crystal lattice; fourthly, a strain hardening of metal resulting in the increase (by 1.5-fold) in scalar and excess dislocation densities relative to the initial state. A long-term operation of rails is accompanied by the formation of structural constituent gradient consisting in a regular change in the relative content of lamellar pearlite, fractured pearlite, and structure of ferrite–carbide mixture along cross-section of railhead. As the distance to the rail fillet surface decreases, a relative content of metal volume with lamellar pearlite decreases, and that with the structure of fractured pearlite and ferrite–carbide mixture increases. As determined, the characteristic feature of ferrite–carbide mixture structure is a nanosize range of grains, subgrains and carbide-phase particles forming it. The size of grains and subgrains forming the type of structure varies in the limits of 40–70 nm; the size of carbide-phase particles located along the boundaries of grains and subgrains varies in the limits of 8–20 nm. A multiaspect character of steel strengthening is detected that is caused by several factors: firstly, the substructural strengthening due to the formation of fragment subboundaries, whose boundaries are stabilized by the carbide-phase particles; secondly, the strengthening by carbide-phase particles located in the bulk of fragments and on elements of dislocation substructure (dispersion hardening); thirdly, the strengthening caused by the precipitation of carbon atoms on dislocations (formation of Cottrell atmospheres); fourthly, the strengthening being introduced by internal stress fields due to incompatibility of crystal-lattices’ deformation of α-phase structural constituents and carbide-phase particles.

Published
2020
Full Text
View/download PDF

16. The Structure and Properties of a Hypoeutectic Silumin Subjected to Complex Electron–Ion-Plasma Processing

Author

Yu. F. Ivanov, V. E. Gromov, D. V. Zagulyaev, S. V. Konovalov, Yu. A. Rubannikova, A. P. Semin

Subjects
hypoeutectic silumin, electroexplosion alloying, titanium, yttrium, electron beam processing, structure, phase composition, wear resistance, Physics, QC1-999
Abstract

The structural-phase states, microhardness, and tribological properties of hypoeutectic silumin after electron-beam treatment are studied by the methods of contemporary physical materials science. The object of the study is hypoeutectic АК10М2Н-type silumin containing 87.88 wt.% of Al and 11.1 wt.% of Si as the base components. The silumin surface is subjected to electron-beam treatment in six various regimes distinct in the density of electron-beam energy. The microhardness measurements of the modified silumin-surface layers enabled to determine three optimal impact regimes (with electron-beam energy densities of 25, 30, and 35 J/cm2), when the modified-layer microhardness exceeds that for the cast silumin. The obtained parameters are as follow: 0.86 ± 0.41 GPa for the cast state; 0.93 ± 0.52 GPa for 25 J/cm2; 0.97 ± 0.071 GPa for 30 J/cm2; 0.96 ± 0.103 GPa for 35 J/cm2. As found, the electron-beam treatment with the optimal parameters results in the formation of the surface whose mechanical and tribological characteristics sufficiently exceed corresponding values for the cast state of silumin. The atomic-force microscopy data correlate with the results on microhardness. The samples treated in the presented regimes are characterised with the fine-grained cellular structure and have the least roughness of the treated layer (of 17–33 nm) and substrate (of 45–57 nm) as compared to other regimes. As revealed, in the treated layer, the fine-grained, graded, and cellular structure is formed, and it transforms into the mixed-type structure when deepening away from the surface of treatment. Depending on the parameters of electron-beam treatment, the thickness of homogenized layer varies and reaches the maximum values of 100 μm at the energy density of 35 J/cm2. As detected, the modified layer is free from intermetallides and consists of the nanocrystalline structure of cellular crystallization. As assumed, these two factors are responsible for the increased mechanical and tribological characteristics of the modified layer. The formation mechanism for structure of cellular and columnar crystallization consisting in the initiation of thermocapillary instability over the ‘evaporated substance/liquid phase’ interface is offered. The mathematical model of the thermal effect of electron beam on the silumin-surface layers is developed.

Published
2019
Full Text
View/download PDF

21. Sovereign wealth funds as an alternative to corporate investment

Author

KRASNOZHON S. V. and IVANOV V. E.

Subjects
economic efficiency, financial instruments, corporate investment, financial assets, financial resources
Abstract

The subject of the study is to analyze the process and efficiency of creating sovereign wealth funds, their structure, functions and investment strategies. Purpose of the article – the main purpose of creating sovereign wealth funds is to mobilize and accumulate investment resources in order to implement state tasks to finance socially important projects. Methodology – the dialectical method of scientific cognition, the method of analysis of needs and opportunities, the case study method allowed to apply the experience of other countries to propose the creation of sovereign wealth funds in Ukraine. Results – this approach of corporate investment will allow accumulating the necessary financial resources for the development of industries that are crucial for the implementation of priority tasks in the issues of economic recovery and development, structural transformations and modernization of production. Conclusions – The creation of funds based on the principles of public–private partnership is a powerful tool for enhancing Ukraine’s economic development. These funds can become a catalyst for the implementation of strategic priorities in economic recovery and development, structural transformation, and modernization of production.

Published
2023
Full Text
View/download PDF

22. Sovereign wealth funds as an alternative to corporate investment

Author

KRASNOZHON S., V. and IVANOV V., E.

Subjects
economic efficiency, financial instruments, corporate investment, financial assets, financial resources
Abstract

The subject of the study is to analyze the process and efficiency of creating sovereign wealth funds, their structure, functions and investment strategies. Purpose of the article – the main purpose of creating sovereign wealth funds is to mobilize and accumulate investment resources in order to implement state tasks to finance socially important projects. Methodology – the dialectical method of scientific cognition, the method of analysis of needs and opportunities, the case study method allowed to apply the experience of other countries to propose the creation of sovereign wealth funds in Ukraine. Results – this approach of corporate investment will allow accumulating the necessary financial resources for the development of industries that are crucial for the implementation of priority tasks in the issues of economic recovery and development, structural transformations and modernization of production. Conclusions – The creation of funds based on the principles of public–private partnership is a powerful tool for enhancing Ukraine’s economic development. These funds can become a catalyst for the implementation of strategic priorities in economic recovery and development, structural transformation, and modernization of production.

Published
2023
Full Text
View/download PDF

30. Application of autodynes in advanced systems of atmosphere radar sensing

Author

Noskov, V. Ya., Ivanov, V. E., Gusev, A. V., Ignatov, K. A., Knyazev, S. T., Kudinov, S. I., Malygin, I. V., Plokhikh, O. V., Ponomarev, O. P., and Chernykh, O. A.

Subjects
СИСТЕМЫ РАДИОЛОКАЦИОННОГО ЗОНДИРОВАНИЯ, АВТОДИННЫЙ ПРИЕМО-ПЕРЕДАТЧИК, ATMOSPHERE RADIO SENSING, РАДИОЗОНДИРОВАНИЕ АТМОСФЕРЫ, АВТОДИН, РАДИОЗОНД, AUTODYNE, AUTODYNE TRANSCEIVER, RADAR SENSING SYSTEMS, RADIOSONDE
Abstract

Поступила: 19.01.2022. Принята в печать: 25.01.2022. Received: 19.01.2022. Accepted: 25.01.2022. Представлены результаты исследований автодинного приемо-передатчика (АПП) для перспективных систем радиолокационного зондирования атмосферы. Разработана математическая модель АПП, представленная в виде автогенератора с одноконтурной колебательной системой, находящейся под воздействием запросного сигнала от РЛС. Выполнен анализ динамики приема сигналов в режиме биений, когда частота принимаемого сигнала находится за пределами полосы синхронизации, а также в режиме захвата, когда частота запросного сигнала попадает в полосу синхронизации АПП. Исследованы шумовые и энергетические параметры и характеристики используемых в качестве АПП СВЧ-генераторов. Выполнены расчеты динамических, шумовых и энергетических параметров и характеристик АПП в зависимости от выбора вида характеристики проводимости активного элемента и положения рабочей точки на ней, а также от условий связи АПП с нагрузкой. Экспериментальные исследования АПП выполнены на примере серийного транзисторного СВЧ-модуля радиозонда МРЗ-3МК на частоту 1680 МГц. Дано описание структурной схемы АПП для аэрологического радиозонда, работающего в режиме биений. Показано, что чувствительность АПП к запросному сигналу определяется флуктуациями амплитуды СВЧ-модуля и полосой пропускания усилителя промежуточной частоты. Установлено, что чувствительность АПП составляет минус 110...120 дБ/Вт, для измерения наклонной дальности 250...300 км достаточно иметь передатчик РЛС с импульсной мощностью 50...100 Вт, при этом средняя мощность его соответствует 0,05...0,1 Вт. The results of studies of an autodyne transceiver (AT) for advanced radar sensing systems of the atmosphere are presented. A mathematical model of the APP has been developed, presented in the form of an oscillator with a single-circuit oscillatory system under the influence of a request signal from the radar. The analysis of the dynamics of signal reception in the beat mode, when the frequency of the received signal is outside the synchronization band, as well as in the capture mode, when the frequency of the request signal falls into the synchronization band of the AT. The noise and energy parameters and characteristics of the microwave generators used as an AT are investigated. Calculations of dynamic, noise and energy parameters and characteristics of the AT are performed depending on the choice of the type of conductivity characteristic of the active element and the position of the working point on it, as well as on the conditions of connection of the AT with the load. The experimental studies of the AT were carried out on the example of a serial transistor microwave module of the MRS-3MK radiosonde at a frequency of 1680 MHz. The description of the structural scheme of the AT for an aerological radiosonde operating in the beating mode is given. It is shown that the sensitivity of the AT to the request signal is determined by fluctuations in the amplitude of the microwave module and the bandwidth of the intermediate frequency amplifier. It is established that the sensitivity of the AT is minus 110...120 dB/W, for measuring the inclined range of 250...300 km is enough to have a radar transmitter with a pulse power of 50...100 W, while its average power corresponds to 0.05...0.1 W.

Published
2022

32. Structural-Phase States of Titanium After an Electroexplosive Alloying and the Subsequent Electron-Beam Treatment

Author

S. V. Karpiy, M. M. Morozov, E. A. Budovskikh, Yu. F. Ivanov, V. E. Gromov

Subjects
Physics, QC1-999
Abstract

The features of a surface relief, structure and phase composition of the hardened layers of commercially pure titanium after electroexplosive aluminizing and boroaluminizing with the subsequent electron-beam treatment are studied by methods of scanning and transmission electron-diffraction microscopies. The distribution of microhardness in depth is studied. As shown, the combined treatment leads to formation of a low roughness of a surface and is characterized by small quantity of microcracks. The total depth of a zone of influence at aluminizing and boroaluminizing is 60 and 90 μm, respectively. The microhardness of a surface increases in 2.3 and 5.5 times, accordingly. Along the depth of the combined-treatment zone, three layers naturally connected with each other are observed: the near-surface layer, which has a boundary determined by the depth of the electron-beam treatment; the intermediate layer with the changed phase composition caused by the electroexplosive alloying; the layer of a thermal influence, in which the hardening is reached due to the structure–phase changes of an alloy base. As revealed, the hardening under electroexplosive aluminizing and electron-beam treatment is reached due to formation of the multiphase structure containing nanoand microcrystalline particles of intermetallic compounds of the titanium–aluminium system; under boroaluminizing, the aluminium and titanium borides of various morphology are also revealed.

Published
2010
Full Text
View/download PDF

37. Application of aerological radar to determine the wind profile in the lower troposphere

Author

Bukrin, I. V., Gusev, A. V., Kudinov, S. I., Ivanov, V. E., Plokhikh, O. V., and Shabunin, S. N.

Subjects
ATMOSPHERIC SOUNDING, ЗОНДИРОВАНИЕ АТМОСФЕРЫ, ПРОФИЛЬ ВЕТРА, RECEIVER NOISE COEFFICIENT, РАДИОЛОКАТОР, КОЭФФИЦИЕНТ ШУМА ПРИЕМНИКА, КОГЕРЕНТНОЕ НАКОПЛЕНИЕ, СПЕКТР ДОПЛЕРОВСКОГО СИГНАЛА, WIND PROFILE, COHERENT ACCUMULATION, RADAR, МЕТЕОРОЛОГИЧЕСКИЕ ПАРАМЕТРЫ АТМОСФЕРЫ, PROBING RADIO PULSES, METEOROLOGICAL PARAMETERS OF THE ATMOSPHERE, PHASE NOISE, DOPPLER SIGNAL SPECTRUM, ФАЗОВЫЙ ШУМ, ЗОНДИРУЮЩИЕ РАДИОИМПУЛЬСЫ
Abstract

Поступила: 20.03.2021. Принята в печать: 31.03.2021. Received: 20.03.2021. Accepted: 31.03.2021. В настоящее время для обеспечения оперативных прогнозов погоды и климата широко используются радиолокационные и радионавигационные системы аэрологического зондирования атмосферы с помощью запускаемых в атмосферу аэрологических радиозондов. Для получение оперативных данных о свободной атмосфере разработаны и эксплуатируются метеорологические радиолокационные системы различного назначения, обеспечивающие измерение метеорологических параметров неконтактными методами Одним из важнейших метеорологических параметров, является вертикальный профиль ветра. Для определения распределения направления и скорости ветра по высоте созданы специализированные радиолокаторы, позволяющие измерять динамические параметры ветра в реальном масштабе времени. В статье рассматривается возможность создания радиолокатора параметров ветра приземной атмосферы на основе модернизации серийного отечественного аэрологического радиолокатора. Технические характеристики радиолокатора – импульсная мощность передающего устройства, чувствительность приемного устройства, возможность точного управления диаграммой направленности антенны по угловым координатам позволяют принципиально обеспечить измерение ветра в приземном слое атмосферы. Основные вопросы модернизации связаны с необходимостью реализации когерентного режима работы приемопередающей системы радиолокатора и обеспечение когерентного накопления энергии отраженного сигнала в течение интервала статистической устойчивости атмосферы. Информация о ветре на измеряемой высоте оценивается по доплеровскому спектру отраженного сигнала от метеорологических неоднородностей. Возможность точного наведения антенны в течение сеанса зондировании позволяет определять вертикальный профиль ветра в диапазоне высот даже в условиях ясного неба. The work was carried out with the financial support of the Ministry of Science and Higher Education of the Russian Federation under the project No. 0836-2020-0020. Currently, radar and radionavigation systems for aerological sounding of the atmosphere with the help of aerological radiosondes launched into the atmosphere are widely used to provide operational weather and climate forecasts. Meteorological radar systems for various purposes have been developed to obtain operational data on the free atmosphere. The systems are operated, providing measurement of meteorological parameters by noncontact methods. One of the most important meteorological parameters is the vertical wind profile. Specialized radars have been created to determine the distribution of wind direction and speed by altitude. They allow measuring the dynamic parameters of the wind in real time. The article considers the possibility of creating a radar for the wind parameters measuring he lower troposphere based on the modernization of a serial domestic aerological radar. Technical characteristics of the radar such as the pulse transmitting power, the sensitivity of the receiver, the ability to control the antenna radiation pattern accurately by angular coordinates make it possible to provide fundamental wind measurement in the lower troposphere. The main issues of modernization are related to the need of implementation of the coherent operation mode into the radar receiver and transmitter and ensuring the coherent energy storage of the reflected signal during the interval of statistical stability of the atmosphere. The information about the wind at the measured altitude is estimated from the Doppler spectrum of the signal reflected from meteorological inhomogeneities. The ability to accurately point the antenna during the sounding session allows determination of the vertical wind profile in the altitude range, even in clear sky conditions. Работа выполнена при финансовой поддержке Минобрнауки РФ по проекту 0836-2020-0020. The work was carried out with the financial support of the Ministry of Science and Higher Education of the Russian Federation under the project No. 0836-2020-0020.

Published
2021

38. Применение аэрологического радиолокатора для определения профиля ветра в приземной атмосфере

Author

Букрин, И. В., Гусев, А. В., Кудинов, С. И., Иванов, В. Э., Плохих, О. В., Шабунин, С. Н., Bukrin, I. V., Gusev, A. V., Kudinov, S. I., Ivanov, V. E., Plokhikh, O. V., Shabunin, S. N., Букрин, И. В., Гусев, А. В., Кудинов, С. И., Иванов, В. Э., Плохих, О. В., Шабунин, С. Н., Bukrin, I. V., Gusev, A. V., Kudinov, S. I., Ivanov, V. E., Plokhikh, O. V., and Shabunin, S. N.

Abstract

В настоящее время для обеспечения оперативных прогнозов погоды и климата широко используются радиолокационные и радионавигационные системы аэрологического зондирования атмосферы с помощью запускаемых в атмосферу аэрологических радиозондов. Для получение оперативных данных о свободной атмосфере разработаны и эксплуатируются метеорологические радиолокационные системы различного назначения, обеспечивающие измерение метеорологических параметров неконтактными методами Одним из важнейших метеорологических параметров, является вертикальный профиль ветра. Для определения распределения направления и скорости ветра по высоте созданы специализированные радиолокаторы, позволяющие измерять динамические параметры ветра в реальном масштабе времени. В статье рассматривается возможность создания радиолокатора параметров ветра приземной атмосферы на основе модернизации серийного отечественного аэрологического радиолокатора. Технические характеристики радиолокатора – импульсная мощность передающего устройства, чувствительность приемного устройства, возможность точного управления диаграммой направленности антенны по угловым координатам позволяют принципиально обеспечить измерение ветра в приземном слое атмосферы. Основные вопросы модернизации связаны с необходимостью реализации когерентного режима работы приемопередающей системы радиолокатора и обеспечение когерентного накопления энергии отраженного сигнала в течение интервала статистической устойчивости атмосферы. Информация о ветре на измеряемой высоте оценивается по доплеровскому спектру отраженного сигнала от метеорологических неоднородностей. Возможность точного наведения антенны в течение сеанса зондировании позволяет определять вертикальный профиль ветра в диапазоне высот даже в условиях ясного неба., The work was carried out with the financial support of the Ministry of Science and Higher Education of the Russian Federation under the project No. 0836-2020-0020., Currently, radar and radionavigation systems for aerological sounding of the atmosphere with the help of aerological radiosondes launched into the atmosphere are widely used to provide operational weather and climate forecasts. Meteorological radar systems for various purposes have been developed to obtain operational data on the free atmosphere. The systems are operated, providing measurement of meteorological parameters by noncontact methods. One of the most important meteorological parameters is the vertical wind profile. Specialized radars have been created to determine the distribution of wind direction and speed by altitude. They allow measuring the dynamic parameters of the wind in real time. The article considers the possibility of creating a radar for the wind parameters measuring he lower troposphere based on the modernization of a serial domestic aerological radar. Technical characteristics of the radar such as the pulse transmitting power, the sensitivity of the receiver, the ability to control the antenna radiation pattern accurately by angular coordinates make it possible to provide fundamental wind measurement in the lower troposphere. The main issues of modernization are related to the need of implementation of the coherent operation mode into the radar receiver and transmitter and ensuring the coherent energy storage of the reflected signal during the interval of statistical stability of the atmosphere. The information about the wind at the measured altitude is estimated from the Doppler spectrum of the signal reflected from meteorological inhomogeneities. The ability to accurately point the antenna during the sounding session allows determination of the vertical wind profile in the altitude range, even in clear sky conditions.

Published
2021

44. Features of remagnetization of the two-layer film structure of the YIG/FeNi

Author

null Kurlyandskaya G. V., null Vas’kovskiy V. O., null Makarochkin I. A., null Gorkovenko A. N., null Feshchenko A. A., null Lepalovskij V. N., null Ivanov V. E., and null Svalov A. V.

Abstract

The results of magneto-optical and magnetometric measurements carried out on two-layer film structures of YIG/FeNi are presented. YIG films were grown by liquid-phase epitaxy, and FeNi films were deposited by magnetron sputtering. It has been established that an interlayer magnetic coupling takes place in the YIG/FeNi system, which is mainly due to magnetostatic interaction. Keywords: yttrium-iron-garnet, permalloy, interlayer coupling, magnetostatic and exchange interaction, magnetic domain structure.

Published
2022

45. Effect of thermomagnetic treatments on the domain structure of Finemet amorphous films

Author

null Lepalovskij V. N. and null Ivanov V. E.

Abstract

Thermomagnetic processing of films of the Finemet type with an easy magnetization axis in the plane under the action of a constant and rotating magnetic field was carried out in order to obtain an isotropic state. After heat treatment in a constant field, the easy magnetization axis was reoriented along the line of action of the field, as a result of which the domain walls were oriented along the new axis. After thermomagnetic treatment in a rotating field, regions with different anisotropy patterns, including isotropic regions, were revealed. Keywords: domain structure, thermomagnetic treatment, rotating magnetic field.

Published
2022

Catalog

Books, media, physical & digital resources
See catalog results