The effect of the nickel sulphide alloys structure on their electrochemical oxidation parameters

The granulation of nickel sulphide alloys results in formation of the ultrafine structure because of their reactivity is increased in the hydrometallurgical processing The phase composition and phase size of nickel sulphide alloys granulated was studied by X-ray and optical microscopy methods It is shown the high cooling rate leads to the crystallization of non-equilibrium phase and dispersion of a metal component The parameters of the electrochemical oxidation of nickel sulfide granular alloys in sulfuric acid solution were estimated The initial potentials of phase components oxidation of nickel sulfide alloys granulated were defined The rate of electrochemical oxidation of nickel sulfide alloys granulated is higher than that at slow-rate cooling Copyright © 2013 IFAC.Russian Academy of Sciences, РАН: 12-I-3-103This research was supported by the Presidium of RAS project No. 12-I-3-103.and Metal Processing;Control (IFAC) - TC 6.2. Mining, Mineral;International Federation of Automatic;TC 6.1. Chemical Process Control;TC 6.3. Power and Energy System

Phase Transitions in Higher Derivative Gravity

This paper deals with black holes, bubbles and orbifolds in Gauss-Bonnet theory in five dimensional anti de Sitter space. In particular, we study stable, unstable and metastable phases of black holes from thermodynamical perspective. By comparing bubble and orbifold geometries, we analyse associated instabilities. Assuming AdS/CFT correspondence, we discuss the effects of this higher derivative bulk coupling on a specific matrix model near the critical points of the boundary gauge theory at finite temperature. Finally, we propose another phenomenological model on the boundary which mimics various phases of the bulk space-time.Comment: 33 pages, 12 figures, LaTeX, typos corrected, clarifications in sections 5 and 6, references adde

Ground-based acoustic parametric generator impact on the atmosphere and ionosphere in an active experiment

We develop theoretical basics of active experiments with two beams of acoustic waves, radiated by a ground-based sound generator. These beams are transformed into atmospheric acoustic gravity waves (AGWs), which have parameters that enable them to penetrate to the altitudes of the ionospheric E and F regions where they influence the electron concentration of the ionosphere. Acoustic waves are generated by the ground-based parametric sound generator (PSG) at the two close frequencies. The main idea of the experiment is to design the output parameters of the PSG to build a cascade scheme of nonlinear wave frequency downshift transformations to provide the necessary conditions for their vertical propagation and to enable penetration to ionospheric altitudes. The PSG generates sound waves (SWs) with frequencies f1 = 600 and f2 = 625 Hz and large amplitudes (100-420ms-1). Each of these waves is modulated with the frequency of 0.016 Hz. The novelty of the proposed analytical-numerical model is due to simultaneous accounting for nonlinearity, diffraction, losses, and dispersion and inclusion of the two-stage transformation (1) of the initial acoustic waves to the acoustic wave with the difference frequency Δf = f2 - f1 in the altitude ranges 0-0.1 km, in the strongly nonlinear regime, and (2) of the acoustic wave with the difference frequency to atmospheric acoustic gravity waves with the modulational frequency in the altitude ranges 0.1-20 km, which then reach the altitudes of the ionospheric E and F regions, in a practically linear regime. AGWs, nonlinearly transformed from the sound waves, launched by the two-frequency ground-based sound generator can increase the transparency of the ionosphere for the electromagnetic waves in HF (MHz) and VLF (kHz) ranges. The developed theoretical model can be used for interpreting an active experiment that includes the PSG impact on the atmosphere-ionosphere system, measurements of electromagnetic and acoustic fields, study of the variations in ionospheric transparency for the radio emissions from galactic radio sources, optical measurements, and the impact on atmospheric aerosols. The proposed approach can be useful for better understanding the mechanism of the acoustic channel of seismo-ionospheric coupling

Influence of boric anhydride upon the physical and chemical properties of ferrosilicon slag

The authors study the influence of boric anhydride upon the physical and chemical properties of slag in the manufacture of ferrosilicon. It is established that adding boric anhydride to the slag changes its refractory quality and its viscosity and eases pouring slag and metal. Slags with optimal composition and properties are described

Convultions assosiated with chemotherapy in a child with acute lymphoblastic leukemia. Clinical case

The aim of this study – to describe and analyse a clinical case of seizures during chemotherapy in a child with acute lymphoblastic leukemia.Цель исследования – описание и анализ клинического случая возникновения судорог на фоне проведения химиотерапии у ребёнка с острым лимфобластным лейкозом

Макроекономічні аспекти розвитку індустрії туризму в Україні та особливості їх регулювання

Макроекономічні аспекти розвитку індустрії туризму в Україні та особливості їх регулювання = Macroeconomic aspects of tourism industry development in Ukraine and the features of its regulation / І. О. Іртищева, Н. П. Тубальцева, І. В. Сіренко, Є. О. Селіванов, Є. В. Шарова // Вісн. ХНАУ. Сер. Економічні науки. – Харків, 2019. – № 4, т. 2. – С. 302–313.Визначено, що туризм являється прибутковою сферою будь якої національної економіки. Обґрунтовано, що Україна об’єктивно має всі передумови для інтенсивного розвитку різних направлень туристичної діяльності. Показано, що територіальна концентрація туристичних підприємств відбиває структуру попиту і залежить від добробуту населення регіону. Приведено статистичні дані як туристичних потоків через кордон України, так і світових лідерів за рівнем витрат на закордонні туристичні подорожі. Доведено, що стан транспортної інфраструктури більшості туристичних територій характеризується як незадовільний. Визначено загальний перелік проблем, які необхідно вирішувати для розвитку індустрії туризму в Україні. Запропоновано системні пропозиції щодо економічного розвитку цієї галузі.It is determined that tourism is a profitable area of any national economy. It is proved that Ukraine objectively has all the prerequisites for the intensive development of various areas of tourism. It is shown that the territorial concentration of tourism enterprises reflects the structure of demand and depends on the welfare of the population of the region. Statistical data of both tourist flows across the Ukrainian border and world leaders in terms of spending on foreign travel are presented. It is proved that the state of the transport infrastructure of most tourist areas is characterized as unsatisfactory. The general list of problems that need to be addressed for tourism industry development in Ukraine is determined. The systematic suggestions for the economic development of this industry are proposed.Определено, что туризм является прибыльной сферой любой национальной экономики. Обосновано, что Украина объективно имеет все предпосылки для интенсивного развития различных направлений туристической деятельности. Показано, что территориальная концентрация туристических предприятий отражает структуру спроса и зависит от благосостояния населения региона. Приведены статистические данные как туристических потоков через границу Украины, так и мировых лидеров по уровню расходов на зарубежные туристические путешествия. Доказано, что состояние транспортной инфраструктуры большинства туристических территорий характеризуется как неудовлетворительное. Определен общий перечень проблем, которые необходимо решать для развития индустрии туризма в Украине. Предложены системные предложения по экономическому развитию этой отрасли

On the effects of mechanical stress of biological membranes in modeling of swelling dynamics of biological systems

We highlight mechanical stretching and bending of membranes and the importance of membrane deformations in the analysis of swelling dynamics of biological systems, including cells and subcellular organelles. Membrane deformation upon swelling generates tensile stress and internal pressure, contributing to volume changes in biological systems. Therefore, in addition to physical (internal/external) and chemical factors, mechanical properties of the membranes should be considered in modeling analysis of cellular swelling. Here we describe an approach that considers mechanical properties of the membranes in the analysis of swelling dynamics of biological systems. This approach includes membrane bending and stretching deformations into the model, producing a more realistic description of swelling. We also discuss the effects of membrane stretching on swelling dynamics. We report that additional pressure generated by membrane bending is negligible, compared to pressures generated by membrane stretching, when both membrane surface area and volume are variable parameters. Note that bending deformations are reversible, while stretching deformation may be irreversible, leading to membrane disruption when they exceed a certain threshold level. Therefore, bending deformations need only be considered in reversible physiological swelling, whereas stretching deformations should also be considered in pathological irreversible swelling. Thus, the currently proposed approach may be used to develop a detailed biophysical model describing the transition from physiological to pathological swelling mode.National Aeronautics & Space Administration (NASA):80NSSC19M0049; PR Space Grant (NASA):NNX15AI11Hinfo:eu-repo/semantics/publishedVersio

Measurement and comparison of individual external doses of high-school students living in Japan, France, Poland and Belarus -- the "D-shuttle" project --

Twelve high schools in Japan (of which six are in Fukushima Prefecture), four in France, eight in Poland and two in Belarus cooperated in the measurement and comparison of individual external doses in 2014. In total 216 high-school students and teachers participated in the study. Each participant wore an electronic personal dosimeter "D-shuttle" for two weeks, and kept a journal of his/her whereabouts and activities. The distributions of annual external doses estimated for each region overlap with each other, demonstrating that the personal external individual doses in locations where residence is currently allowed in Fukushima Prefecture and in Belarus are well within the range of estimated annual doses due to the background radiation level of other regions/countries

Method for Producing Zinc Powder

FIELD: physical chemistry. SUBSTANCE: invention relates to the production of zinc powder from zinc-containing raw materials. The method involves the electrochemical reduction of zinc from a zinc-containing compound in an alkaline electrolyte. Zinc oxide is used as a zinc-containing compound, the electrochemical reduction is carried out by direct contact of the solid phase of zinc oxide with the cathode, while the cathode current density is 4000-5000 A/m2, and the alkali content in the electrolyte during the electrolysis is maintained in the range of 30-70 g/l. To increase the speed of the process, 5-10% of the zinc powder by weight of the zinc oxide is added to the zinc oxide before electrolysis. EFFECT: method makes it possible to increase the specific rate of zinc reduction and to obtain a fine powder. 1 cl, 1 dwg.Изобретение относится к получению цинкового порошка из цинксодержащего сырья. Способ включает электрохимическое восстановление цинка из цинксодержащего соединения в щелочном электролите. В качестве цинксодержащего соединения используют оксид цинка, электрохимическое восстановление проводят при непосредственном контактировании твердой фазы оксида цинка с катодом, при этом катодная плотность тока составляет 4000 - 5000 А/м2, а содержание щелочи в электролите по ходу электролиза поддерживают в диапазоне 30-70 г/л. Для повышения скорости процесса перед электролизом в оксид цинка добавляют 5-10% цинкового порошка от массы оксида цинка. Способ позволяет повысить удельную скорость восстановления цинка и получить тонкодисперсный порошок. 1 ил