The structure, oxygen non-stoichiometry, defect equilibrium, and thermodynamic properties of perovskite-type Pr0.5Ba0.25Sr0.25MnO3–δ manganite were studied. It was shown that the manganite can be air ...synthesized in one step at 1450 °C. Though having a disordered arrangement of Pr, Ba, and Sr atoms, the compound crystallizes with a tetragonal structure (S.G. I4/mcm) due to the regular tilts of MnO6 octahedra. The oxygen content in oxide as a function of oxygen partial pressure and temperature was measured by coulometric titration, and the data were used for the modeling of defect equilibrium. The oxygen content measurements show stability of the manganite at 973–1223 K and oxygen pressure decrease down to 10−16–10−12 atm. The equilibration of defects in Pr0.5Ba0.25Sr0.25MnO3-δ involves oxygen exchange with the gaseous ambient, intrinsic electron excitation, and oxygen disordering reactions. According to thermodynamic calculations, oxygen sites available for oxygen exchange are characterized by praseodymium-rich coordination. The disordering caused by the half substitution of barium by strontium leads to a lower energy of chemical bonding of the labile oxygen in Pr0.5Ba0.25Sr0.25MnO3–δ compared to the parent Pr0.5Ba0.5MnO3–δ manganite.
PrBa0.5Sr0.5Mn2O6-δ was investigated in terms of structural features, phase stability, oxygen non-stoichiometry, defect equilibrium, and thermodynamic properties. Display omitted
•The deep Sr doping in Pr0.5Ba0.25Sr0.25MnO3–δ results in an enhanced phase stability.•PBSM crystallizes with tetragonal structure due to regular tilts of MnO6 octahedra.•Oxygen sites available for exchange in PBSM are characterized by Pr-rich coordination.•The disordering in PBSM structure is caused by the half substitution of Ba by Sr.•Energy of chemical bonding of the labile oxygen in PBSM lower than in parent PBM.
Abstract
A probe method for measuring the ion current density and theoretical calculations of the dynamics of neutral and charged plasma particles using the ionization region model (IRM) is used to ...study short and ultra-short pulse high-power impulse magnetron sputtering (HiPIMS). This paper studies reasons for the increase in the average ion current density on the substrate at shorter pulses, when the average discharge power does not change. HiPIMS pulses are applied to the copper target at constant values of average discharge power (1000 W) and peak current (150 А), respectively, while the pulse time of the discharge voltage ranges from 4 to 50
µ
s. A power supply with low output inductance is designed to generate ultra-short pulses. It is shown that shorter discharge pulses lead to a multiple growth (from 2 to 7 mA cm
−2
) in the average ion current density on the substrate and a growth in the peak intensity of Ar
+
, Cu
+
and Cu
2+
recorded by optical emission spectroscopy. A theoretical model of this effect is based on the spatially averaged IRM, which considers afterglow effects. According to theoretical calculations, the increase in the average ion current density on the substrate is determined by the plasma dissipation in the ionized region after the pulse ends. Also, a decrease in the copper deposition rate from 180 to 60 nm min
−1
with decreasing pulse time from 40 to 4
µ
s is explored. A comparison of experimental data with those obtained earlier shows that the suggested dependences of the ion current density and deposition rate on the HiPIMS pulse time are typical for discharge systems with different cathode materials and configurations, i.e., for single- and dual-magnetron systems. This indicates a common nature of the phenomena observed and additionally confirms the results obtained.
The article substantiates the authors’ position, supported by empirical data, on the sharp increase in the intellectual intensity of managerial activities and on the transformation of the managerial ...profession into one of the most complex, gaining particular importance in the organisation of the innovation process for technological sovereignty. The increasing role of management science in understanding the ongoing turbulent changes, developing methodologies for proactive management and identifying competencies in demand in the economy is highlighted. The need for the introduction of advanced learning in these conditions is demostrated; the authors’ experience in its development and implementation in terms of specific organisational models, content and teaching methods is presented. Within the framework of the proposed concept of further education, it is necessary to introduce a management specialisation focused on specific industries into the existing system of higher education. It will provide enhanced fundamental and applied training, a significant increase in the volume of practice and will enable students to master the engineering-economic and engineering-managerial knowledge necessary for taking into account interdisciplinary relationships between high technology, economics and finance when making management decisions.
For every sufficiently large odd p, we present a continual set of nonfinitely based varieties of groups of exponent p. The properties of these varieties make it possible to answer some open questions ...on varieties of groups.
The article reasons the need for changing the model of management education and corresponding tools and approaches to bring them in line with the challenges of a technological breakthrough and ...organisational transformations in the national economy that is going through an unprecedented overhaul of global economic ties and is restricted by sanctions. The authors suggest a paradigm of proactive training that is characterised by its focus on foreseeing changes by having a breakthrough research agenda, a quick conversion of research results into the educational content, research projects and activities, the flexibility of the content and formats of the educational process. The conceptual mechanism of a system for the anticipatory training of managers has been designed; potential methodologies have been identified for building educational modules for bachelor’s and master’s degree programs. By analysing the methodologies it was possible to develop a comprehensive approach to creating high-value educational products. The article describes some of the proprietary technologies that the authors use when implementing proactive education programs in practice.
The scientific novelty of the article lies in the formulation of the training concept for managers aimed at solving complex interdisciplinary tasks of a technological breakthrough. In terms of the practical value, the article presents a mix of educational technologies for the implementation of the concept. It includes electronic proactive leaning system, conveyor of continuous competence enhancement, digital modular architecture of the learning process, “module-in-module” technology.
The present paper is devoted to the influence of the support surface roughness on adhesion of a film-support system (a stainless steel (St3) support + a copper film). The film was deposited using a ...magnetron. The film was 7 μm thick. Prior to coating with the copper film the sample surface was treated with Low-Energry Power High-Current Electron Beams (LEHCEB) or Compressive Plasma Flows (CPF). An experimental facility similar to the magnetoplasma compressor was made. The surface was exposed to LEHCEB in modes that make it smoother or rougher. The sample surface gets rougher, if treated with CPF. As the profilometry data show, the contact area rises 4 times. And this, in its turn, strengthens the adhesion.
The article aims to study the structure of and improve the model for the fostering of managerial competencies to solve the problems of a technological breakthrough in the domestic economy. The ...authors apply their proprietary approach that makes it possible to reveal the range of interdisciplinarity and to specify its content. Methods and tools for mastering the competencies in demand are developed. As the empirical base which proves the validity of their сonclusions, the authors cite their own research as well as the results of the analysis of educational programs in engineering management implemented at the leading universities of the world, and the expert opinions of the heads of energy enterprises and professors of Russian universities. The paper analyzes the key factors in the formation of interdisciplinary competencies: a management paradigm towards which the educational process is oriented, a model of knowledge and skills that is adequate to the content of the tasks of a technological breakthrough, a methodology for analyzing interdisciplinary relationships in managerial decisions. The article outlines the relevant experience of training managers of various levels by the Department of Energy Management Systems and Industrial Enterprises of Ural Federal University.
The study is scientifically novel as it discovers a new approach to understanding interdisciplinarity when determining the managerial competencies necessary for a technological breakthrough. The practical significance of the article is due to the fact that it presents the experience of implementing the developed approach to the training of managers with an increased readiness to constantly embrace and implement future technologies.
The article substantiates the need for a radical review of approaches to the training of managers in high technological industries, whose professional activity context is defined by continuous ...crises, growing uncertainty, dynamic trends, the massive emergence of the newest technical, organizational, and IT solutions, and a profound transformation of markets. Building upon their own research, analysis of expert opinions from top managers, university professors and the best practices of the world's leading universities, the authors identify trends indicating the growing role of the fundamental knowledge possessed by managers, who are capable of raising up to the challenges of an unstable environment. Links are determined between fundamental training and the flexibility of managerial thinking. A conceptual vision is presented of the peculiarities of managerial thinking and of conditions for developing its flexibility in the educational process.
The scientific novelty of the article includes arguments substantiating the need for stepping up fundamental training in line with objective demand for changes in the content of managerial functions. Such training is based on three components: methodology of anticipatory management; scientific and technological foundations of production and technologies of the future; a vision of professional activity and changes that will be brought about by the introduction of new technologies. On the applied side, the authors have designed a concrete structure of fundamental training and a mix of training methods that promote flexibility of thinking and have proved effective as part of Masters in Management programs.
This work presents the results of work on import substitution of anticorrosive protective coatings of pile products of hydraulic structures for the categories of corrosion aggressiveness CX and ...immersion Im4.
The bombardment of the substrate with accelerated ions from the plasma during the magnetron sputtering process is an effective way of controlling the energy transfer to the coating. One of the ways ...to increase the ion flux on the substrate is to change the parameters of the discharge power supply pulses. This work investigates the effect of the discharge current pulse amplitude on the average ion current density on the substrate in short-pulse high power impulse magnetron sputtering (s-HiPIMS). During sputtering, the peak discharge current varied from 25 to 250 A with a fixed pulse duration of 6 μs and an average discharge power of 1 kW. Experimental results and theoretical calculations show that the average ion current density on the substrate increases twofold when the amplitude of the discharge current pulses is increased from 25 to 60 A. As the amplitude of the discharge current pulses is further increased, the average ion current density on the substrate stops growing and begins to decrease at currents above 150 A. The paper discusses the reasons for the nonlinear dependence of the average ion current density on the substrate on the amplitude of the discharge current pulses.
•Short-pulse high power impulse magnetron sputtering is studied.•Peak discharge current varied at fixed pulse duration and discharge power.•Discharge current amplitude affects the average ion current density on the substrate.•Nonlinear dependence of the average ion current density is discussed.
