Grain refinement in a Cu-Cr-Zr alloy during multidirectional forging

Structural changes during plastic deformation were studied in a Cu-0.3%Cr-0.5%Zr alloy subjected to multidirectional forging up to a total strain of 4 at the temperatures of 300 K and 673 K. The deformation behavior was characterized by a rapid increase in the flow stress at an early deformation followed by a steady-state flow at large strain. The development of the new ultrafine grains resulted from the progressive increase in the misorientations of the strain-induced low-angle boundaries, which evolve into high-angle boundaries with increasing cumulative strain through a strain-induced continuous reaction that is quite similar to continuous dynamic recrystallizatio

Architecture and evolution of the Simferopol military hospital from the moment of foundation till present

The article presents history of development of one of the oldest medical institutions, the military hospital named after St. Luke of Crimea, located in the city of Simferopol. For more than 200 years, it has been undergoing many changes and hardships, it has been subjected to many tests, the author considers how the architecture of this institution has changed over the past years. © 2023 Author(s)

Non-conservative Evolution of Cataclysmic Variables

We suggest a new mechanism to account for the loss of angular momentum in binaries with non-conservative mass exchange. It is shown that in some cases the loss of matter can result in increase of the orbital angular momentum of a binary. If included into consideration in evolutionary calculations, this mechanism appreciably extends the range of mass ratios of components for which mass exchange in binaries is stable. It becomes possible to explain the existence of some observed cataclysmic binaries with high donor/accretor mass ratio, which was prohibited in conservative evolution models.Comment: LaTeX, 32 pages, to be published in Astron. Z

Generation of tunable visible picosecond pulses by frequency-doubling of a quantum-dot laser in a PPKTP waveguide

We demonstrate a compact all-room-temperature picosecond laser source broadly tunable in the visible spectral region between 600 nm and 627 nm. The tunable radiation is obtained by frequency-doubling of a tunable quantum-dot external-cavity mode-locked laser in a periodically-poled KTP multimode waveguide. In this case, utilization of a significant difference in the effective refractive indices of the high- and low-order modes enables to match the period of poling in a very broad wavelength range. The maximum achieved second harmonic output peak power is 3.25 mW at 613 nm for 71.43 mW of launched pump peak power at 1226 nm, resulting in conversion efficiency of 4.55%

Precipitation and flow behavior of AISI 630 stainless steel deformed at elevated temperatures

Hot compression tests were performed on the samples of AISI 630 stainless steel in the temperature range of 900-1050 C and at strain rates of 10–3- 1 s21. Single peak stress flow behavior was observed at all deformation conditions. An irregular relationship was found between the peak point of flow curves and processing condition, i.e., temperature and strain rate. The stress relaxation tests at the temperature range of 900-1050 C revealed that dynamic precipitation (DP) of carbides in the matrix and grain boundaries causes the considered irregularities in the peak stres

Tempering behavior of a low nitrogen boron-added 9% Cr steel

The effect of tempering temperature on microstructure and mechanical properties was studied in alow- nitrogen, high-boron, 9% Cr steel. After normalizing and low-temperature tempering, cementite platelets precipitated within the martensitic matri

Влияние импортозамещения на рост производства минеральных продуктов и металлургии: краткосрочное и долгосрочное прогнозирование базовых отраслей национального хозяйства

The purpose of the study is to identify ways of short- and medium-term development of mineral production and metallurgy in the Russian Federation in the context of the policy of sanctions based on economic and mathematical modeling. The impact of sanctions on production in the basic sectors of the Russian economy, as well as the impact of import substitution on production in the short- and long-term is investigated. The research methodology includes panel regression with fixed effects and Bayesian vector autoregression (BVAR model). The sanctions index is calculated based on a sentimental analysis of the texts of news publications. This index is based on the results of computer analysis of a set of thematic texts (evaluation of the frequency of words and phrases, correlation analysis, case analysis based on the BERT neural network). The paper demonstrates the importance of an industry-specific approach to the implementation of import substitution policy in view of its time horizon. For example, for the mineral products industry, the current import substitution policy can be considered effective in terms of the production index forecast, and for the metallurgical industry, the import substitution policy needs to be revised, since a sharp decline is expected in the short-term when the baseline scenario is implemented, and in the long-term production stabilizes without showing growth. As a result, the efficiency of the import substitution policy is considered to be completely dependent on the industry in which it is implemented. Fund intensity and other factors affecting industry cycles must be considered in order to forecast policy results. Import substitution also has a long-term positive impact.Цель исследования заключается в выявлении на основе экономико-математического моделирования путей краткосрочного и среднесрочного развития минерального производства и металлургии РФ в условиях политики санкционного воздействия. Исследуется влияние санкций на производство в базовых отраслях экономики РФ, а также импортозамещения на производство в краткосрочном и долгосрочном периодах. Методология исследования включает в себя панельную регрессию с фиксированными эффектами и байесовскую векторную авторегрессию (BVAR модель). Санкционный индекс рассчитывается на основе сентимент-анализа текстов новостных публикаций. Построенный индекс основан на результатах компьютерного анализа массива тематических текстов (оценку частотности слов и словосочетаний, анализ корреляций, тематический анализ на основе нейронной сети BERT). Работа демонстрирует значимость индивидуального отраслевого подхода к проведению политики импортозамещения с учетом ее временного горизонта. Так, например, для отрасли производства минеральных продуктов текущая политика импортозамещения может считаться эффективной с точки зрения прогноза индекса производства, а для металлургической отрасли политика импортозамещения нуждается в пересмотре, поскольку при реализации базового сценария на краткосрочном периоде ожидается резкий спад, а в долгосрочном производстве стабилизуется, не показывая рост. Таким образом утверждается, что эффективность политики импортозамещения во многом зависит от отрасли, где такая политика проводится. Необходимо учитывать фондоемкость и другие факторы, влияющие на цикличность в отрасли, что позволяет прогнозировать результаты проводимой политики. Также подтверждается положительное влияние импортозамещения в долгосрочном периоде

Evolution of the number of accreting white dwarfs with shell nuclear burning and of occurrence rate of SN Ia

We analyze temporal evolution of the number of accreting white dwarfs with shell hydrogen burning in semidetached and detached binaries. We consider a stellar system in which star formation lasts for 10 Gyr with a constant rate, as well as a system in which the same amount of stars is formed in a single burst lasting for 1 Gyr. Evolution of the number of white dwarfs is confronted to the evolution of occurrence rate of events that usually are identified with SN Ia or accretion-induced collapses, i.e. with accumulation of Chandrasekhar mass by a white dwarf or a merger of a pair of CO white dwarfs with total mass not lower than the Chandrasekhar one. In the systems with a burst of star formation, at $t=$10 Gyr observed supersoft X-ray sources, most probably, are not precursors of SN Ia. The same is true for an overwhelming majority of the sources in the systems with constant star formation rate. In the systems of both kinds mergers of white dwarfs is the dominant SN Ia scenario. In symbiotic binaries, accreting CO-dwarfs do not accumulate enough mass for SN Ia explosion, while ONeMg-dwarfs finish their evolution by an accretion-induced collapse with formation of a neutron star.Comment: 11 pages, 2 figures, accepted by Astronomy Letter

Axiological survey of the modern cultural-educational practices of personality

The monograph is devoted to the hardly explored topic that reveals methodological, theoretical and praxeological potential of modern cultural- educational practices of personality as a unity of diversity and continuum of methods of human’s existence, synthesis of its life practices, in particular economic, religious, political and etc. The authors updated the role of education, science, cultural-educational practices in common to mankind sense in modernization of cultural-spiritual life. The monograph can be used by scholars, postgraduate students and students. The majority of the problems that are highlighted in the monograph have discursive and discussion character and incite to competent dialogue between all people that are interested in these questions

The Atmospheric Chemistry Suite (ACS) of Three Spectrometers for the ExoMars 2016 Trace Gas Orbiter

The Atmospheric Chemistry Suite (ACS) package is an element of the Russian contribution to the ESA-Roscosmos ExoMars 2016 Trace Gas Orbiter (TGO) mission. ACS consists of three separate infrared spectrometers, sharing common mechanical, electrical, and thermal interfaces. This ensemble of spectrometers has been designed and developed in response to the Trace Gas Orbiter mission objectives that specifically address the requirement of high sensitivity instruments to enable the unambiguous detection of trace gases of potential geophysical or biological interest. For this reason, ACS embarks a set of instruments achieving simultaneously very high accuracy (ppt level), very high resolving power (>10,000) and large spectral coverage (0.7 to 17 μm—the visible to thermal infrared range). The near-infrared (NIR) channel is a versatile spectrometer covering the 0.7–1.6 μm spectral range with a resolving power of ∼20,000. NIR employs the combination of an echelle grating with an AOTF (Acousto-Optical Tunable Filter) as diffraction order selector. This channel will be mainly operated in solar occultation and nadir, and can also perform limb observations. The scientific goals of NIR are the measurements of water vapor, aerosols, and dayside or night side airglows. The mid-infrared (MIR) channel is a cross-dispersion echelle instrument dedicated to solar occultation measurements in the 2.2–4.4 μm range. MIR achieves a resolving power of >50,000. It has been designed to accomplish the most sensitive measurements ever of the trace gases present in the Martian atmosphere. The thermal-infrared channel (TIRVIM) is a 2-inch double pendulum Fourier-transform spectrometer encompassing the spectral range of 1.7–17 μm with apodized resolution varying from 0.2 to 1.3 cm−1. TIRVIM is primarily dedicated to profiling temperature from the surface up to ∼60 km and to monitor aerosol abundance in nadir. TIRVIM also has a limb and solar occultation capability. The technical concept of the instrument, its accommodation on the spacecraft, the optical designs as well as some of the calibrations, and the expected performances for its three channels are described