Many scientists of the world were engaged in the study and development of various schemes and models of hydraulic elevators for the purpose of excavation and hydraulic transport of hydraulic mixtures ...1-22. For the specific conditions of the selected research object, we determined the main sizes and parameters of the hydraulic elevator, which allows cleaning the water area of the bottom water intake of the spillway of the Tupalang hydroelectric station, using the hydrostatic pressure at the object concentrated in front of its dam. To clarify the particle size distribution of sediment deposited at the inlet head of the water intake of the Tupalang reservoir water outlet, samples of bottom sediments were taken and their particle size distribution was analyzed in laboratory conditions. At the water intake area of the 1st tier of the Tupalang reservoir, the deposited sediments are represented by smaller particles, the diameter of which is from 5 mm to 0.1 mm, and in percentage terms, their share is 95%. The main results are given for calculating and justifying the parameters of a hydraulic elevator for cleaning sediment from the water area of the inlet head of the water outlet structure of the first tier of the Tupalang reservoir. When determining and substantiating the main sizes of the hydraulic elevator, theoretical and experimental research methods were used, and the method of S.M.Shtin was applied.
Low Dissipative State of Bi2Se3 and Bi2Te3 Surfaces Gahramanov, S. Sh; Abdullayev, Y. A.; Orujova, H. V. ...
Surface investigation, x-ray, synchrotron and neutron techniques,
2024/6, Volume:
18, Issue:
3
Journal Article
Peer reviewed
The morphology of the (0001) surface is studied using a scanning probe microscope, and the effect of electrolytic deposition of potassium ions on the surface properties of layered Bi
2
Se
3
and Bi
2
...Te
3
crystals is investigated by modulation electroreflectance spectroscopy. The process of prolonged deposition of potassium atoms onto the (0001) surface of Bi
2
Se
3
and Bi
2
Te
3
crystals after adsorption causes their intercalation into van der Waals spaces of the quintets closest to the surface. Surface metallization with potassium and broadening of van der Waals gaps in the near-surface region during intercalation due to an increase in the barrier height lead to a weakening of interlayer interaction, a decrease in the overlap of wave functions of different layers, and a weakening of dispersion. As a result of electrodeposition, potassium intercalates into the interlayer spaces. This entails modification of the surface accompanied by an increase in the concentration of charge carriers and their mobility, which implies a transition of the near-surface region to a metallic state with lower dissipation.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
We consider the method of calculating the pressure in apparatuses with swirling flows, depending on the different materials. The influence on the calculation of pressure losses in the two-phase ...swirling flows of various parameters for the organization of fuel combustion processes, mass and heat transfer, dust collection. Dependence of pressure drop on the amount of energy consumed and the choice of blowers for apparatuses with swirling flows. The causes of pressure drops in two-phase swirling flows are given and listed. The loss of gas kinetic energy in apparatuses with twisted and counter twisted flows of gas suspensions exceeds losses from all other causes, that only this loss should be taken into account. The peculiarities of design and pressure losses in vortex pressureless apparatuses are considered. The results of investigating the dependence of pressure losses in the apparatus on the air flow rate through the vortex chamber and the results of investigating the effect of the ratio of flow rates through the apparatus channels are presented.
Existing methods are considered for designing sedimentation tanks in the Burjar hydroelectric power station to solve the problem of abrasive wear of aggregates. Weighted sediments abrade the lining ...of derivational and station water conduits, as well as the working elements of hydraulic turbines. In the Burjar hydroelectric power station, there is a problem associated with the abrasive wear of the units. Abrasive wear of turbines leads to a significant drop in their efficiency, and therefore, a decrease in the power and energy generation of a hydroelectric power station, a reduction in the service life of hydroturbine equipment, and a fragment of wear. For the design of the sump, geological and hydrological information was collected about the Burjar hydroelectric power station. The sump is projected onto the derivation channel of the Burjar hydroelectric station. To determine the size of the sump, laboratory analysis of the water of the Burjar hydroelectric station was carried out. The hydraulic calculation of the sump includes determining the main dimensions of the chamber, sediment volume, flushing turbidity, and siltation time of the dead chamber volume with sediment. The calculation is described by the method of academician E.A. Zamarin. According to the method of E.A. Zamarin, the width of the chamber is 9.6 m and the length of the chamber is 73 m. These results are accurate and they were used during the design of the sump.
The LHCb detector is due to be upgraded for processing high-luminosity collisions, which will increase data bandwidth to the event filter farm from 100 GB/s to 4 TB/s, encouraging us to look for new ...ways of accelerating Online reconstruction. The Coprocessor Manager is a new framework for integrating LHCb's existing computation pipelines with massively parallel algorithms running on GPUs and other accelerators. This paper describes the system and analyzes its performance.
In the article, using the example of the «identity integration disorder», the author’s conceptual framework, the application of the theory of psychophysiological isomorphism that originated in the ...framework of classical gestaltpsychology to the modern realities of the development of psychiatric science is considered. Te formation of the concept of «integration of identity» in the scientifc and historical aspect is traced. With the help of pathopsychological and neurophysiological methods of research, the hypothesis of uniting the four main «circles» of mental pathology in the composition of the psychic education under consideration is substantiated.
In this paper we consider local "complementary" generalized Morrey spaces
with variable exponent p(x) and a general function ω(r) defining a Morrey-type norm. We prove the boundedness of the ...Hardy-Littlewood maximal operator and Calderón-Zygmund singular operators with standard kernel in such spaces in case of unbounded sets Ω ⊂ ℝ
n
. Also we prove the
boundedness of commutators of Hardy-Littlewood maximal operator and Calderón-Zygmund singular integral operators.
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BFBNIB, GIS, IJS, KISLJ, NUK, PNG, UL, UM, UPUK
Vibrational spectra of TlInS
2
crystals in the terahertz frequency range (0.1–3 THz) have been obtained and analyzed. The observed low-frequency band is attributed to the libration oscillations of ...nanolayers (so-called boson peak). A correlation between the coherent low-frequency oscillation and a disordered character of the crystal structure is shown. A conclusion is made on the presence of a topological disorder that manifests itself on the layered subsystem level.
Lanthanide borohydride
tris
-tetrahydrofuranates (Ln(BH
4
) · 3THF, where THF is tetrahydrofuran and Ln is La, Nd, Sm, Gd, Er, Yb, and Lu) is synthesized via the exchange reaction of lanthanide(III) ...chloride and sodium borohydride in THF. It is found that synthesis proceeds according to a stepwise mechanism and the product of the reaction (lanthanide borohydride) initiates the process. The two-step character of the desolvation of Ln(BH
4
)
3
· 3THF under steady-state conditions in the temperature range of 300 to 400 K is determined through X-ray phase and chemical analyses, tensiometry, and gas volumetry. It is established that one mole and then two moles of THF are removed from the initial sample at the first and second steps, respectively. Equations for barograms are obtained and the thermodynamic characteristics of desolvation of Ln(BH
4
)
3
· 3THF under study are calculated. Gibbs energy values of the stages of process are determined semi-empirically. The law of its change for the entire series of Ln(BH
4
)
3
· 3THF is determined with the emergence of the tetrad effect.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Providing a reasonable forecast of the required properties of intermetallic compounds (hereinafter also referred as intermetallides or IM) is an important scientific and commercial problem, which may ...be solved by focusing scientific researches and permanent generation of knowledge in this field. To date, researches in chemistry and physics of IM have been developing empirically for a simple reason, due to the complexity of describing the relationship between the crystal structure and chemical bonds, and, therefore, between all the properties of IM. IM is mainly characterized by metal type of chemical bond, as well as specific metallic properties. At the same time, among IM, there are also salt-like compounds with ionic bond, i.e. valency compounds formed from elements of different chemical nature, being stoichiometric compounds. The examples of such compounds are compounds with intermediate bond type, i.e. ionmetal and covalently-metal, as well as covalent bond types (e.g., NaAu). In the series of compounds of Mg with elements of the IV subgroup, along with decreasing the difference in the electrochemical characteristics of the components, the change in the IM properties is observed, from those peculiar to ionic compounds (for example, Mg2Si, Mg2Ge) to the properties typical of metals (Mg2Pb), etc. Due to the fact that lanthanides form the largest group of elements of the periodic system occurring in nature, and Mg is a relatively active chemical element in terms of IM formation (for example, it forms three IM with cadmium - Mg3Cd, MgCd and MgCd3), its oxides in slag provide decreasing average silicon content and increasing the stability of the silicon content in iron, being an important process indicator in the course of physicochemical reactions occurring in a blast furnace (for example, in the process of iron production). The presence of Si impurity (along with O, Au, Ti, V, Zr) produces the greatest effect on efficiency of solar cells, etc. 1–3. Based on the foregoing, it is very important to study the state function, i.e. enthalpy of magnesium-lanthanide systems, rich in magnesium, and, based on the results of computer simulation, taking into account molecular dynamics method and other similar studies 4–8, to model regularities of changes in melting enthalpy of IM of the mentioned systems. The issue of modeling the pattern of change in melting enthalpy of IM of magnesium-lanthanide (Mg-Ln) magnesium-rich systems is considered based on systematic analyzing melting enthalpy of IM of Mg-Ln magnesium-rich system, including Mg2Ln, Mg3Ln and equimolar compound MgLn, implemented using semi-empirical method developed by N.S. Poluektov.
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