Phase equilibria and thermodynamic properties of oxide systems on the basis of rare earth, alkaline earth and 3d-transition (Mn, Fe, Co) metals. A short overview of

Review is dedicated studies of phase equilibria in the systems based on rare earth elements and 3d transition metals. It’s highlighted several structural families of these compounds and is shown that many were found interesting properties for practical application, such as high conductivity up to the superconducting state, magnetic properties, catalytic activity of the processes of afterburning of exhaust gases, the high mobility in the oxygen sublattice and more

Crystal structure and oxygen nonstoichiometry of oxides in the Ba-Me-Me’-Y-O (Me, Me’=Co, Fe) system

Polycrystalline BaМe1-xYxO3-δ(Me=Co, Fe) samples were synthesized by a conventional route and glycerol-nitrate technique. According XRD patterns of single phase solid solutions BaCo1-xYxO3-δ (0.1≤x≤0.4) and BaFe0.9-yY0.1CoyO3-δ (0.05≤y≤0.15) were indexed using Pm3m space group. The unit cell parameters were refined using Rietveld full-profile analysis. Oxygen non-stoichiometry of these solid solutions was measured by means of thermogravimetric technique within the temperature range 298-1273 K in air.The work was supported under financial support from RFBR № 13-03-00958 and Ministry of Science and Education of Russian Federation within the limits of the Federal target program "Scientific and scienceeducational cadres of innovative Russia for 2009-2013"

Phase equilibria, crystal structure and oxygen content of intermediate phases in the Y-Ba-Co-O system

The phase equilibria in the Y-Ba-Co-O system were systematically studied at 1373 K in air. The intermediate phases formed in the Y-Ba-Co-O system at 1373 K in air were: YBaCo2O5+δ, YBaCo4O 7 and BaCo1-yYyO3-δ (0.09≤y≤0.42). It was shown that YBaCo2O5+δ possesses tetragonal structure with the 3ap×3a p×2ap superstructure (sp. gr. P4/mmm). High-temperature X-ray diffraction analysis of the YBaCo2O 5+δ in the temperature range from 298 K up to 1073 K under Po2=0.21 atm has not shown any phase transformations. The value of oxygen content for the YBaCo2O5+δ at room temperature was estimated as 5.40 and at 1323 K it was equal to 5.04. Thermal expansion of sample shows a linear characteristics and the average thermal expansion coefficient (TEC) is about 13.8×10-6, K-1 in the temperature range 298-1273 K. The homogeneity range and crystal structure of the BaCo1-yYyO3-δ (0.09≤y≤0.42) solid solutions were determined by X-ray diffraction of quenched samples. All BaCo1-yYyO3-δ solid solutions were found to have cubic structure (sp. gr. Pm3m). The unit cell parameters were refined using Rietveld full-profile analysis. Oxygen nonstoichiometry of BaCo 1-yYyO3-δ solid solutions with 0.1≤y≤0.4 was measured by means of thermogravimetric technique within the temperature range 298-1373 K in air. Thermal expansion of BaCo 1-yYyO3-δ (y=0.0; 0.1; 0.2; 0.3) samples was studied within the temperature range 298-1200 K in air. The projection of isothermal-isobaric phase diagram for the Y-Ba-Co-O system to the compositional triangle of metallic components was presented. © 2013 Elsevier Inc

Pulse wave velocity and other indicators of arterial stiffness in hypertension comorbidity and chronic obstructive pulmonary disease

The aim is to study pulse wave velocity (PWV) and other parameters of arterial stiffness in patients with comorbid arterial hypertension (AH) and chronic obstructive pulmonary disease (COPD). Materials and methods. 32 patients with a combination of AH and COPD (group 1), 30 patients with isolated hypertension (group 2), 18 patients with isolated COPD (group 3), 30 healthy subjects (control group) were examined. Applanation tonometry and pulse wave contour analysis at the carotid-femoral segment were made by SphygmoCor (AtCor Medical). Results. Aortic systolic blood pressure in patients with the combination of hypertension and COPD was higher compared to the group of the patients with isolated hypertension by 9.83% (p=0.02), and the patients with COPD by 41.5% (p = 0.000042), respectively. Central pulse pressure in the first group was higher compared to the second group by 29.58% (p=0.00022), in the third group - by 53.4% (p=0.0029). The combination of hypertension and COPD (β=0.42, p=0.00019), age (β=0.39, p=0.0002) and the level of aortic pulse pressure (β=0.54, p=0.001) were marked as independent factors of PWV increasing according to the multiple regression analysis. Conclusion. In patients with a combination of hypertension and COPD the increase in PWV, systolic and pulse pressure in the ascending aorta was observed, compared to patients with isolated hypertension, isolated COPD and the control group during applanation tonometry

The influence of strontium and cobalt content on crystal structure and properties of Nd1-xSrxFe1-yCoyO3- oxides

In the present work the homogeneity range, crystal structure, oxygen nonstoichiometry, thermal properties and electrical conductivity of partially substitutedNd1-xSrxFe1-yCoyO3-δ oxides versus temperature, strontium and cobalt content was studied

Photonics of boron fluoride and zinc dipyrromethene complexes

Spectral, photophysical, photochemical characteristics for mononuclear and binuclear dipyrromethenes in complexes with BF2 (BODIPY), bis-BODIPY and bis-helicates ([Zn2(L)2]) are described. The role of substituents (type and location in the ligand) and the medium in which dipyrromethene complexes are placed (solvents, solid-state matrices), the effect of different complexing agents (p- and d-elements) on the photonics of the complexes are discussed. The results of studying the lasing and photochemical properties of complexes under the action of laser irradiation are presented. In addition, for the described complexes the stability in the ground and excited states in protic media are estimated. Based on the analysis of the results discussed possibilities of practical application of these compounds to creating various optical devices