V. L. Volkov

Ion state of atoms and the properties of perovskite-like compound CaCu3V4O12

The binding energies and valence state of atoms in the perovskite-like compound CaCu3V4O12 have been determined using XPS spectroscopy. The stoichiometry of this phase is formulated as Ca2+Cu2+Cu2+(V25+V24+O12). Under an air atmosphere, the phase interacts with water vapor and oxygen. As a result, Ca(OH)2 is formed on its surface, the Cu+ and V4+ ion concentrations decrease, and the Cu2+ and V5+ concentrations increase in association. Raman spectra show shortened cation-anion bond lengths and cation-anion-cation bond angles in CaCu3V4O12 compared to perovskite CuVO3; the two structures are alike. The electrical conductivity, magnetic susceptibility, thermal and sensor properties of CaCu3V4O12 in aqueous salt solutions have been studied.

High-pressure defect phase CexCu3V4O12

AbstractNonstoichiometric perovskite oxide CexCu3V4O12 (space group Im

Marine terraces of Western Sakhalin Island

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V3O7 · H2O oxide nanostructures: Synthesis and study

Z = 2, a = 7.264–7.328 Å) with cationic vacancies was prepared barothermally. This compound has metal-type conductivity, paramagnetic properties, and a phase transition.

Sodium-doped vanadium oxide nanorods

A new cubic perovskite-like vanadium bronze of composition Na0.25Cu0.75VO3 , with a lattice parameter of 7.2517(1) Å, is obtained by reacting NaVO3 , V2O5 , and Cu2O at 1100°C and 8 GPa. It exhibits metallic conduction, with a sharp change in resistivity above 200°C, and, presumably, undergoes a phase transition near 280°C. The thermal properties of the new vanadium bronze are studied in air and helium at normal pressure.

Synthesis, Structure, and Properties of Ammonium Polyvanadomolybdate Xerogels

Abstract Biostratigraphical and sedimentological studies of deposits of terraces with heights of 2–3, 3–4, 4–6, 8–10, 12–15, 20–30, 35–40, 60–80 and 100–120 m on Western Sakhalin Island have shown that they were all marine in origin. The upper complex of terraces (Q I –Q II ) formed during a period of slow tectonic uplift ( − in this area to 120 m above modern sea level. The lower complex of terraces (Q III –Q IV ) may have formed in response to sea level oscillations without any influence of tectonic uplift.

Synthesis and magnetic properties of M0.08Ti0.91V0.09O2 + δ · nH2O (M = Cr, Mn, Fe, Co, Ni) nanopowders

AbstractWe report the first synthesis, at high pressure and temperature (p = 6.0−8.0 GPa, t = 1000°C), of SrxCu3V4O12 (x = 0.67−1.0), a cation-deficient perovskite-like phase of variable composition (sp. gr. Im