216 research outputs found
The choice of poles rational number of the traction induction motors under different energy efficiency requirements for the drive
Выполнен сопоставительный анализ электромеханических характеристик тяговых асинхронных двигателей с различным числом полюсов при различных фиксированных превышениях температуры обмотки статора. Предложены критерии, формирующие множество Паретооптимальных решений. Представлен метод выбора наилучшего решения из совокупности Паретоэффективных альтернатив. Установлена низкая эффективность «бубликообразной» конструкции с большим числом пар полюсов.The report made a comparative analysis of the electromechanical characteristics of traction induction motors with different numbers of poles at various fixed overtemperature of the stator winding. The criteria that form the set Pareto-optimal solutions are proposed. The method of choosing the best solutions from the set of Pareto-efficient alternatives is described. There is a low efficiency of "donut-shaped" design with a large number of pole pairs is founded
Molecular dynamics simulation of the Ni – FLiNaK interface: adsorption layers as origin of metal passivity
The method of classical molecular dynamics was used to study the Ni (solid) – FliNaK (melt) phase separation boundary at temperatures of 800 K, 1000K , and 1200 K. An ab initio-based pairwise model is developed to describe the interactions that take place at the Ni – FLiNaK interface. It was shown that at temperatures of 800 K and 1000 K, lithium and fluorine ions are predominantly adsorbed on the nickel surface in the form of a two-dimensional ordered structure. Such a dense layer prevents the dissolution of nickel and the metal solid has no defects in the surface layer. However, at a temperature of 1200 K the structure of the adsorption layer is noticeably disturbed with the partial replacement of lithium ions by sodium ones. Along with higher temperature, this leads to the formation of point defects and degradation of the surface layers of the nickel crystal lattice.https://doi.org/10.15826/elmattech.2023.2.02
Thermodynamics and Phase Transitions of Electrolytes on Lattices with Different Discretization Parameters
Lattice models are crucial for studying thermodynamic properties in many
physical, biological and chemical systems. We investigate Lattice Restricted
Primitive Model (LRPM) of electrolytes with different discretization parameters
in order to understand thermodynamics and the nature of phase transitions in
the systems with charged particles. A discretization parameter is defined as a
number of lattice sites that can be occupied by each particle, and it allows to
study the transition from the discrete picture to the continuum-space
description. Explicit analytic and numerical calculations are performed using
lattice Debye-H\"{u}ckel approach, which takes into account the formation of
dipoles, the dipole-ion interactions and correct lattice Coulomb potentials.
The gas-liquid phase separation is found at low densities of charged particles
for different types of lattices. The increase in the discretization parameter
lowers the critical temperature and the critical density, in agreement with
Monte Carlo computer simulations results. In the limit of infinitely large
discretization our results approach the predictions from the continuum model of
electrolytes. However, for the very fine discretization, where each particle
can only occupy one lattice site, the gas-liquid phase transitions are
suppressed by order-disorder phase transformations.Comment: Submitted to Molecular Physic
Thermophysical characteristics of radioactive graphite - Water vapor system
The article considers thermophysical characteristics of radioactive graphite - water vapor system in temperature range 373-3273K. The research was made by thermodynamic modeling method using TERRA software. We determined 4 temperature intervals in which changes of thermophysical characteristics of radioactive graphite - water vapor system occur. © 2017 The Authors, published by EDP Sciences
Historical and statistical data on the development of the domestic alcoholic beverages industry
The method of historical and statistical data analysis makes it possible to identify development and characteristic patterns, both temporary and permanent, production criteria for various branches of the food industry. The application of this method made it possible to trace formation of the alcohol industry inRussiaand identify critical historical events that influenced its development. The article presents and analyzes statistical data on the production of the main types of alcoholic beverages industry since 1913
Analysis of Comparative Constructions as Means of Reconstructing the Author’s Consciousness
One of the components of the grammatical structure of the art text - comparative construction - is considered. The authors believe that through the analysis of the comparisons it is possible to comprehend the peculiarities of the worldview and language of the writer. The research urgency is caused by the fact that the study of grammar in the cognitive aspect is based on the anthropocentric direction of modern linguistics. The novelty lies in the combination of structural-semantic and cognitive methods of analysis of language units with the aim of reconstructing the author’s consciousness. The definitions for the components of the structure of comparative constructions are given. Comparative constructions selected by continuous sampling from Esenin’s “small” poems and his poem “Pugachev” are comprehensively considered: from the point of view of formal-semantic organization, as a means of organizing the artistic image and in the light of the theory of conceptual metaphor. Structural-semantic classification of comparative constructions are developed. In addition, they are seen as a means of creating a syncretic art image. In this case attention is paid to their relationship with such tropes, as metaphor, metamorphosis, impersonation. The result of the cognitive analysis the field-target and area-sources of all selected comparative constructions are described. The study reveals the dominances of Esenin’s author consciousness and traces their change
Thermodynamics of Electrolytes on Anisotropic Lattices
The phase behavior of ionic fluids on simple cubic and tetragonal
(anisotropic) lattices has been studied by grand canonical Monte Carlo
simulations. Systems with both the true lattice Coulombic potential and
continuous-space electrostatic interactions have been investigated. At
all degrees of anisotropy, only coexistence between a disordered low-density
phase and an ordered high-density phase with the structure similar to ionic
crystal was found, in contrast to recent theoretical predictions. Tricritical
parameters were determined to be monotonously increasing functions of
anisotropy parameters which is consistent with theoretical calculations based
on the Debye-H\"uckel approach. At large anisotropies a two-dimensional-like
behavior is observed, from which we estimated the dimensionless tricritical
temperature and density for the two-dimensional square lattice electrolyte to
be and .Comment: submitted to PR
Effect of the entropy on the shear viscosity of metallic glasses near the glass transition
We measured the shear viscosity of 14 metallic glasses differing with their
mixing entropy . It is found that the viscosity at the glass
transition temperature significantly increases with .
Using calorimetric data, we calculated the excess entropy of all glasses
with respect to their maternal crystalline states as a function of
temperature. It is shown that the excess entropy both at room
temperature and at \textit{decreases} with . It is
concluded that glasses with "high mixing entropy" correspond
to MGs with \textit{low} excess entropy . The origin of the increased
shear viscosity at of glasses with high is determined by
their reduced excess entropy .Comment: 12 pages, 4 Figure
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