Effect of anion doping on mobility of ionic charge carriers in solid solutions based on Ba2In2O5

In the work, mobilities of oxygen and protons are determined for F --substituted solid solutions based on brownmillerite Ba 2In2O5 and their concentration dependences are analyzed. It is found that small additives of the more mobile anion (F - ions) promote an increase in oxygen mobility as a result of additional effects of repulsion of ions of different nature in the anion sublattice. Mobility of oxygen at high fluoride concentrations decreases due to the overlapping of migration paths of diffusion, as both anions, fluoride ions and oxygen ions, move via oxygen vacancies. Concentration dependences of mobility of proton carriers have a similar character, which is related to the effect of the oxygen sublattice. The anion doping method used in the work can be recommended as the general method for improvement of the transport characteristics of oxygen-ionic and protonic conductors with a perovskite-like structure. © 2013 Pleiades Publishing, Ltd

Electric properties of oxyfluorides Ba2In2O 5-0.5x F x with brownmillerite structure

Synthesis of fluoro-substituted substances based on brownmillerite Ba 2In2O5 is carried out. The width of the homogeneity region of the Ba2In2O5-0.5x F x (0 < x ≤ 0.25) solid solution was established using X-ray analysis. Measurement of temperature dependences of conductivity in atmospheres with different partial pressure of water vapor (pH2O = 3.3 and 2 Ч 103 Pa) showed an increase in conductivity at T ≤ 550 C in a humid atmosphere, which is due to appearance of proton transport. The dependence of conductivity on partial oxygen pressure (pO2 = 0.21 Ч 105 to 10-15 Pa) is studied in the temperature range of 500-1000 C; ion transport numbers are calculated. The method of polarization measurements was used to determine transport numbers of fluoride. Total conductivity is divided into ion (proton, oxygen, and fluoride ion) and electron components. Analysis of concentration dependences of conductivities showed that low concentrations of fluoride allow increasing both the total and partial conductivities (oxygen-ion and proton) and, besides, allow shifting the "order-disorder" phase transition by 100 C to the low temperature range. © 2013 Pleiades Publishing, Ltd

The lichens and allied fungi of the southern part of the Kenozersky National Park (Arkhangelsk Region, NW Russia)

The paper presents the first data on lichen diversity in the Kenozersky National Park (Arkhangelsk Region, Northwest Russia). As a result of the study, 263 species and 1 subspecies of lichens and allied fungi were found in the southern part of the national park. Seventeen lichen species are reported for the first time for Arkhangelsk Region. Biatora albidula is a new species for Northwest European Russia. Two recorded species are included in the Red Data Book of Russian Federation and 7 in the Red Data Book of Arkhangelsk Region. Pycnothelia papillaria can be recommended for inclusion to the Red Data Book of Arkhangelsk Region

The Effect of Simultaneous Homo- and Heterogeneous Doping on Transport Properties of Ba2In2O5

In this article, the possibility of application of simultaneous homogeneous and heterogeneous doping has been described for the first time. The composite 0.7Ba1.95In2O4.9F0.1⋅0.3Ba2 InNbO6 has been obtained by in situ solid-state method. The scanning electron microscopy and thermogravimetry investigations have beencarried out; the electrical properties have been examined. It has been proved that simultaneous homogeneous and heterogeneous doping is a prospective method for obtaining high-conductive proton electrolytes. Keywords: brownmillerite, composite, anionic doping, fluorin

Optical and photoelectron spectroscopy studies of KPb2Cl 5 and RbPb2Cl5 laser crystals

The paper presents the results of experimental study of electronic structure of RbPb2Cl5 and KPb2Cl5 laser crystals performed by the optical and photoelectron spectroscopy methods. On the basis of the optical absorption and low-temperature reflection spectra of these crystals we have determined the energy positions of the edges of the low-energy tail of the host absorption, the positions of the first excitonic absorption peaks, and exciton binding energies. The bandgap widths of these crystals at 8 K were estimated as Eg = 4.83 and 4.79 eV, respectively. Qualitative and quantitative analysis of RbPb2Cl 5 and KPb2Cl5 crystals were made on the basis of the core states photoelectron spectra. The elemental composition of the (0 0 1) surfaces of the crystals, the chemical state of the host atoms, the electronic structure of the valence band of the crystals were discussed on the basis on the spectroscopic data. © 2012 Elsevier B.V. All rights reserved

ANALYSIS OF THE DIGITAL TRANSFORMATION OF GENERAL EDUCATION

Digital transformation of the society, boosted by the COVID-19 pandemic, has determined new processes in the socio-economic sphere. Foreign and domestic researchers are unanimous in their opinion that digitalization is the main trend of global development, and the need for digital transformation of education is preconditioned by organizational, technological, managerial, economic, and other changes taking place in various spheres of society, economy and production. Object of the study: the digital transformation process. Subject: general education. Goal: to identify the essence and characteristics of the implementation of digital transformation processes in general education. Objectives: to analyze the essence and semantic understanding of the "digital transformation" category; to describe the types and structure of the main processes of digital transformation in general education. Methods: methodological approaches: systemic approach; research methods: theoretical (analysis of information sources; comparative study; content analysis; generalization, systematization). Conclusions: there is no unity in the scientific attribution of the concepts of "digitalization of education", "digital transformation of education"; analysis of the prospects of digital transformation of general education indicates that its main positive effects may be as follows: ensuring equality of educational opportunities and continuity of education; updating the goals and content of education; optimizing forms, methods, teaching and methodological support of the educational process and the students’ learning and cognitive activities; creating conditions for personalized learning; increasing the effectiveness of quality control and monitoring; reducing the amount of routine work for management and teaching staff, etc.; based on the analysis of scientific research, the problem of information security of electronic educational resources used in general education has been identified; an analysis of the current situation on the software market is presented, and general recommendations on the protection of data recorded in electronic educational resources are give

Subunit Mobility and the Chaperone Activity of Recombinant αB-Crystallin

The comparison of the chaperone-like activity of native and covalently cross-linked human αB-crystallins has confirmed the important role of the subunit mobility in the chaperoning mechanism. Our data clearly demonstrate that the chaperone-like activity of α-crystallin is not only a surface phenomenon as was suggested by some researchers