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

Phase equilibria, crystal structure and oxygen nonstoichiometry of the complex oxides in Sm – (Sr, Ba) – (Co, Fe) – O systems

Received: 18.01.2018. Accepted: 14.02.2018. Published: 10.05.2018.Present paper contains available information on the phase equilibria in the Sm – (Sr, Ba) – (Co, Fe) – O systems, including the synthesis routes used, crystal structure, which is often depended on oxygen nonstoichiometry, the data on thermodynamic stability of complex oxides, the obtained results on the homogeneity ranges of solid solutions, formed in the systems, and graphical presentation of phase relations in a form of phase diagrams

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

Assessment of the system of lipid peroxidation - anti oxidant defense in children with essential arterial hypertension by the methods of spectrophotometry and chemiluminescence

The article presents the results of the research of some indices of lipid peroxidation and antioxidant defense in children of 11-13 years with essential arterial hypertension that were obtained by the methods of spectrophotometry and chemiluminescence. Quantity of products of lipid peroxidation - antioxidant defense in blood serum of patients with essential arterial hypertension significantly exceeds this index in control group. Intensity of the lipid peroxidation processes expressed by the indices of chemiluminescence was higher in patients with essential arterial hypertension than in control group

Assessment of entrepreneurial territorial attractiveness by the ranking method

The relevance of the researched problem is caused by existence of differentiation in development of separate regional units (urban districts and municipalities) within the region. The aim of this article is to offer a method, which determines the level of differentiation in development of various components of the region, and also in producing a set of recommendations for local government administration to achieve higher level in development of their territories. The leading approach to the research of this problem is the ranking method of regional units according to cumulative socioeconomic potential and integral risk. The results of the research are: the estimation procedure for entrepreneurial territorial attractiveness is offered and tried out, with the use of municipal formations of the Samara region as an example; the advantages and “bottlenecks” in development of the concrete urban district are educed; specific measures for realization of advantages and (or) elimination of “bottlenecks” are offered. The materials of the research can be useful for developing strategy for improvement of the region by regional public authorities, for leveling-off of social and economic differentiation of separate regional units, and also for developing of scientifically based municipal programs of support and development of entrepreneurship. © 2016 Karpova et al

Biological, cytomorphological and karyological heterogeneity of transformed cell lines derived from domestic pig (Sus scrofa L.) organs

The main advantage of transformed cell lines as compared to primary ones is that they allow generation of the stable material suitable for long-term research and practical use. Therefore, development of new continuous cell cultures from various animal tissues is of great practical importance. Results of examination of transformed cell lines derived from organs of domestic pigs (Sus scrofa L.) for their biological, cytomorphological and karyological features are described in the paper. The said cell cultures are confirmed to be susceptible to various animal viruses. Also, a procedure for preparation of new diploid cell culture from porcine spleen (SSs – Splеen Sus scrofa) is described. Based on the obtained data analysis it was concluded that the epithelial cells derived from trypsinized porcine spleens could be successfully immortalized. All transformed cell lines of porcine origin have similar morphology with predominated epithelium-like forms. Some of them – SPEV, А4 С2 , RSK – tend to adopt a spherical shape in suspension. Such cell lines as PSGK-30 and PPES cell lines form partial multilayer or they are characterized by significant monolayer compaction with pseudosyncytium formation. Only pseudodiploid cell culture (SPEV cell culture) tends to grow in suspension, it also grows in rotating culture flasks. Karyological transformations in different cell cultures stabilized at certain level. Spontaneous increase in chromosome numbers in the main population of transformed cell lines towards triploidy resulted in stabilization of culture properties and increase in proliferation. PSGK-30 cell culture has the highest modal class – 64 chromosomes. Near-diploid cultures (А4 С2 , RSK) demonstrate stable growth properties and are similar to SPEV cell culture in adopting spherical cell forms in medium, monolayer character and cell morphology. PK-15 cell culture having a distinct karyotype under different cultivation conditions while retaining other culture properties is found to be the most adaptive. A new transformed diploid SSs cell culture is developed by long-term incubation, subcultivation (more than 80 passages) and selection at the FGBI “ARRIAH” laboratory; it can remain diploid or may spontaneously become heteroploid-immortalized during further passaging. The cell hyperploidy is very likely to enhance telomerase activity, which in turn stabilizes immortalization and results in proliferative activity increase The cell viability has been maintained so far by regular reseedings (split ratio – 1:2–1:3) performed 1–2 times a week

The state of lipoperoxidation processes in boys with obesity

The problem of obesity is extremely relevant for modern medical science and healthcare, and child and adolescent obesity deserves special attention. It seems to be interesting to trace the interrelation of pathological processes in obesity in the form of metabolic disorders at the level of the organism and at the cell level - disorders in the system of lipid peroxidation. Studies in adolescent boys are relevant, as there has been a general increase in the incidence in this age category. The purpose of the research was to study the state of the system "lipid peroxidation - antioxidant protection" in adolescent boys with exogenous-constitutional obesity. 19 adolescent boys with obesity were examined in comparison with the control group. Spectrophotometric and fluorometric methods of examination were used. An increase in the level of secondary lipid peroxidation products - ketodienes and conjugated trienes (1.65 times) - was revealed in adolescent boys with obesity. In the antioxidant defense system, differences in this group included reduced values of α-tocopherol (1.42 times), retinol (1.51 times) and superoxide dismutase activity (1.19 times), in the absence of statistically significant changes in the total antioxidant activity (AOA) in blood and components of glutathione status. The revealed disorders allow to recommend the complex therapy including prescription of antioxidants and medicines directed on normalization of lipid exchange at the given category of patients

Preparation, crystal structure and properties of HoBaCo 2-xFexO5+δ

A series of samples of overall composition HoBaCo2-xFe xO5+δ with 0.0 ≤ x ≤ 0.8 were prepared by glycerin nitrate technique in air and in pure oxygen. Irrespective of atmosphere used the homogeneity range of single phase iron substituted holmium barium cobaltate was proved to exist within the range 0.0 ≤ x ≤ 0.4. All samples prepared in air and samples within the compositional range 0.2 ≤ x ≤ 0.4 obtained in oxygen possess tetragonal ap × ap × 2ap (sp. gr. 4/mmm) structure. HoBaCo2O 5+δ and HoBaCo1.9Fe0.1O 5+δ synthesized in oxygen crystallized in orthorhombic a p × 2ap × 2ap (sp. gr. mmm) structure. The structural parameters were refined by the Rietveld analysis. It was shown that parameter a remains practically constant while parameter c gradually increases with the increase of iron content. The changes of oxygen content in HoBaCo2-xFexO5+δ (x = 0, 0.2, 0.4) were measured by TGA within the temperature range 25-1100 °C in air. The absolute value of oxygen content was determined by the reduction of the samples in hydrogen flow. The influence of oxygen and iron content on the crystal structure has been discussed. The chemical stability of HoBaCo 2-xFexO5+δ in contact with the solid electrolyte materials Ce0.8Sm0.2O2 and Zr 0.85Y0.15O2 was examined. © 2013 Elsevier Ltd

Rational antimicrobial chemotherapy: assessment of the level of basic knowledge of general practitioners. Final results of the KANT project

The irrational use of medicines leads to a decrease in the quality of care, an increase in treatment costs and side effects. In the case of antibacterial drugs, in addition to all the above-mentioned consequences, their improper use can lead to an aggravation of the existing and quite challenging problem of our time-the growth of antibiotic resistance among pathogenic microorganism

A Study of the Crystal Structure of SmCaCo1−xFexO4−δ and Sm0.9Ca1.1Fe1−yCoyO4−δ Solid Solutions

Complex oxides with general compositions SmCaCo1−xFexO4−δ and Sm0.9Ca1.1Fe1−yCoyCO4−δ are synthesized using the glycerol-nitrate technique at 1100 °C in air. By powder X-ray diffraction it is determined that SmCaCo1−xFexO4−δ solid solutions exist in a composition range 0 ≤ x ≤ 0.3 and Sm0.9Ca1.1Fe1−yCoyO4−δ solid solutions exist in a composition range 0 ≤ y ≤ 0.7. The samples with high concentrations of cobalt ions are found to crystallize in the tetragonal unit cell (space group I4/mmm), whereas the solid solutions enriched with iron ions have the orthorhombic structure (space group Bmab). For all single phase samples the unit cell parameters and volume and the structural parameters (atomic coordinates and bond lengths) are calculated by the full-profile Rietveld method. © 2019, Pleiades Publishing, Ltd