Publications by authors named "O A Merkulov"

The crystalline and electronic band structures, thermodynamic stability, oxygen non-stoichiometry and high-temperature transport properties of perovskite-like solid solutions with a general formula SrFeTaO, where , ≥ 0, are thoroughly studied using a combination of experimental and theoretical methods. It is argued that the basic compound SrFeTaO possesses an orthorhombic lattice symmetry, while its tantalum-doped derivatives belong to a tetragonal space group. Importantly, the purposeful addition of a certain deficiency in a strontium sublattice is shown to be a valid method for stabilizing the SrFeTaO oxides with an excess tantalum content.

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Simultaneous syngas and pure hydrogen production through partial oxidation of methane and water splitting, respectively, were demonstrated by using mixed ionic-electronic conductors. Tubular ceramic membranes prepared from LaSrFeO perovskite were successfully utilized in a 10 M lab scale reactor by applying a radial arrangement. The supply of methane to the middle area of the reaction zone was shown to provide a uniform distribution of the chemical load along the tubes' length.

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Perovskite-type LaSrFeMoO synthesized glycine nitrate combustion and sintered at 1350 °C was found to have an orthorhombic lattice, which transforms upon heating into a rhombohedral and then a cubic one. The oxygen content and electrical conductivity in this oxide were measured in the range of oxygen partial pressures from 10 to 0.5 atm at 750-950 °C by coulometric titration and four-probe dc techniques, respectively.

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Article Synopsis
  • The study investigates the structure and oxygen non-stoichiometry of perovskite-type PrBaSrFeO synthesized at high temperatures, confirming a cubic structure through X-ray diffraction but showing short-range order through electron diffraction.
  • It finds that increased oxygen deficiency promotes ordering in the material, while substituting barium with strontium has the opposite effect, affecting the defect equilibrium.
  • The research also measures oxygen content in relation to temperature and pressure, revealing how variations in strontium concentration influence oxygen vacancy behavior and p-type carrier concentration in the oxides.
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Data of otoneurologic, audiologic and vestibulometric research were analyzed in both adult and child patients suffering from acute otitis media with focus on probable spread of inflammatory non-purulent process into inner ear and brain. Combination of available printed data and own research during the 2010-2021 y.y.

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