Solid solutions of Ba2(In1 ? xAlx)2O5: Structural evolution and hydration processes

Solid solutions of the composition Ba₂(In_{1 − x} Al _x )₂O₅[VO]₁ (0 ≤ x ≤ 0.20) with an incomplete oxygen sublattice were obtained. It was established that, along with an increase in parameter x, there is disordering of oxygen vacant positions and a transition from the structure of brownmillerite to that of defect perovskite. It was demonstrated that the phases under study are characterized by an ability for reversible interaction with water vapors in the temperature range 150–450°C. During this process, proton defects, predominantly in the form of OH⁻ groups, are formed in the oxide structure. We conclude that in a number of solid solutions, the amount of intercalated water declines upon an increase in the aluminum content.     

Synthesis of monosubstituted 1,2,4,5-tetrazines – 3-amino-1,2,4,5-tetrazines

Chemistry of Heterocyclic Compounds - The substitution of pyrazolyl moiety in 3-(3,5-dimethyl-1H-pyrazol-1-yl)-1,2,4,5-tetrazine with N-nucleophiles provided a series of highnitrogen tetrazine...     

Mixed Problem for a General 1D Wave Equation with Characteristic Second Derivatives in a Nonstationary Boundary Mode

Mathematical Notes - We use a modified method of characteristics to derive an explicit formula for the unique stable classical solution of a linear mixed problem for a general one-dimensional wave...     

Electrical properties of Ba2(In1 − x Al x )2O5 solid solutions

The electric conductivity of perovskite-like Ba₂(In_{1 ? x} Al _x )₂O₅ solid solutions (0 < x ≤ 0.20) characterized by structural disordering in the oxygen sublattice was studied as a function of temperature and partial pressure of oxygen in an atmosphere with a low content of water vapors ( $p_{H_2 O}$ = 3 × 10^?5 atm). When In³⁺ was partially replaced by Al³⁺, the oxygen ion conductivity increased because of the disordering of oxygen structural vacancies, leading to a significant increase in the total electric conductivity of the samples.