arXiv subjects

O. I. Anyfrieva

Publications and source records attributed to O. I. Anyfrieva.

3 recordsLinked to original sources

arXiv2016

Solution enthalpies of barium cerates co-doped by rare-earth elements and indium

The dissolution enthalpies of BaCe0.7Ho0.2In0.1O2.85 and BaCe0.7Sm0.2In0.1O2.85 were measured by method of solution calorimetry in 1M hydrochloric acid with adding 0.1 M KI. The obtained data were compared with earlier measured data on dissolution enthalpies of BaCe0.7Nd0.2In0.1O2.85, BaCe0.7Gd0.2In0.1O2.85. The dependence of dissolution enthalpies from lanthanide radius was constructed. As was shown the relationship is not linear.

cond-mat.mtrl-sci↗

arXiv2012

Formation enthalpy of BaCe0.7Nd0.2In0.1O2.85

In this paper for the first time we synthesized the compound BaCe0.7Nd0.2In0.1O2.85 by solid-state reaction. The phase has orthorhombic structure (space group Pmcn). We also measured the standard formation enthalpies of BaCe0.7Nd0.2In0.1O2.85 by solution calorimetry in 1 M HCl with 0.1 M KI. We determined the stability of Nd(In)-doped barium cerate with respect to mixtures of binary oxides. On the basis of these data we established that above-mentioned mixed oxide is thermodynamically stable with respect to their decomposition into binary oxides at room temperatures. We also established that BaCe0.7Nd0.2In0.1O2.85 oxide is thermodynamically favoured than BaCe0.8Nd0.2O2.9.

cond-mat.mtrl-sci↗

arXiv2004

Decomposition of solid solutions in the Nd-Ba-Cu-O system and its influence on changing transport characteristics

Thermochemical characteristics of Nd1+xBa2-xCu3Oy solid solutions were studied by solution calorimetry. Dependences of formation enthalpies from Nd content were constructed. It was established that decomposition of solid solution on the basis of Nd123 phase took place both in inert and in oxygen atmosphere. As a result of decomposition the different mixtures such as solid solutions with increasing and decreasing Nd content and BaCuO2 were formed. Obtained thermochemical data were compared with results of measurements of transport characteristics. It was established that treatment of samples at 550-600 C led to increasing critical current and decreasing Tc.

cond-mat.mtrl-sci↗