Кафедра перекладу та іноземних мов (ДМетІ)

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http://crust.ust.edu.ua/handle/123456789/14615
ENG: Department of Translation and Foreign Languages (Dnipro Metallurgical Institute, DMetI)

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Browsing Кафедра перекладу та іноземних мов (ДМетІ) by Author "Abramova, Olena V."

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    Electrical Properties of Tin Oxide Based Varistors with PbO Addition in Humid Air
    (Lithuanian Academy of Sciences, 2023) Gaponov, A. V.; Abramova, Olena V.
    ENG: The purpose of this paper is to study the electrical properties of the obtained ceramic varistors with PbO addition in the environments with different air relative humidity. Methodology. The studied ceramics (99.4–x) SnO2–0.5Co3O4–0.05Nb2O5–0.05Cr2O3–xPbO (mol.%) with the PbO concentration of х = 0, 0.1, 0.5, 0.7, 1 and 2 mol.% was produced by the traditional ceramic technology. The sample baking was taking place at 1250°С during 1 h. In the process of electrode production, the In-Ga eutectic was applied. The CVC of the samples were measured in the contained chambers with relative humidity of 10–86% above the surface of the water solution of a proper salt (the details are given in Ref. [8]). The values of nonlinearity coefficient α = (E/j) (dj/dE) were measured at the current density of j = 1 mА/cm2. The breakdown electric field E1 was estimated at the same value of j. The electrical conductivity σ = j/E was obtained in the area of low currents. The humidity sensitivity coefficient S was calculated for the j(E) characteristic at the low field by S = (σw2 – σw1)/σw1, where σw1 and σw2 are the electricalconductivity of the sample in the area of low currents at the air relative humidity w1 = 10% and w2 = 86%, respectively. The value of the activation energy of electrical conduction Eσ was calculated with the help of temperature dependences of electrical conductivity in the low electric field by σ = σ0 exp (–Eσ/kT), where σ0 = const, k is the Boltzmann constant, and T is the absolute temperature. Findings. In order to lower the breakdown electric field and simultaneously decrease the humidity sensitivity coefficient of tin oxide ceramics, one can use a small quantity of lead oxide addition. The lowest values of these parameters (E1 = 4390 V/cm and S = 172) were obtained at the concentration of PbO 0.5–0.7 mol.% in SnO2–Co3O4–Nb2O5–Cr2O3–PbO ceramics. The values of the nonlinearity coefficient of such samples are 41–45. The enhancement of PbO concentration increases the low-field electrical conductivity while passing from high voltage varistors to low voltage ones. The obtained new results help to produce SnO2 based varistors that are designed for lower voltage and are less sensitive to the environment influence. Originality. SnO2–Co3O4–Nb2O5–Cr2O3 ceramics is one of the most investigated systems for varistor production [11–13]. It has great non-ohmic current–voltage characteristics (CVC) with quite a large nonlinearity coefficient α ≈ 40–50 and at the same time great gas sensitive properties. Nowadays, the actual task is to decrease the sensitivity of this system to the air humidity. Earlier, this effect was achieved with adding Bi2O3, V2O2 and CuO to the SnO2–Co3O4–Nb2O5–Cr2O3 system [3, 5, 7–9]. Bi2O3, V2O2 and CuO oxides have low melting temperatures, which are less than burning temperatures of ceramics. The samples with such additions have liquid phases in the process of sintering, that is why the sensitivity of these ceramics to the environment decreases. But the humidity sensitivity coefficient of these samples remains quite large [3]. In order to solve the problem of varistor humidity sensitivity, we decided to add lead oxide to the SnO2–Co3O4–Nb2O5–Cr2O3 system. PbO has the melting point Тm ≈ 886°C, therefore the synthesis of such ceramics is the liquid-phase one. There are no published papers about the lead oxide addition to such system. Practical value. The findings may be used in the production of tin oxide SnO2 ceramics with PbO additions in order to use it in optically transparent conducting materials, gas sensitive sensors and varistors.
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    Word Formation in American English Political Advertising
    (MAGNANIMITAS Assn., The Czech Republic, 2023) Vukolova, Kateryna; Zirka, Vira; Styrnik, Nataliia; Khabarova, Nataliia; Abramova, Olena V.
    ENG: Currently, election political advertising, which is one of the most important areas of the advertising industry, performs persuasive and suggestive functions. Particular attention is paid to the political slogan, the effectiveness of which is enhanced by the use of figures of speech that facilitate the perception of the information embedded in them. Speaking about the forms of political communication, one should pay special attention to political advertising as such an aspect of it, which especially actively uses all the possibilities of the language. The task of the study was to clarify the linguistic features of the texts of English-language political advertising.