Preparation and properties of silicon- and titanium-containing hybrid nanocomposite films based on ethyl cellulose

Nanocomposite hybrid films containing silicon and titanium compounds in the polymer matrix are prepared through the sol-gel method via the hydrolytic polycondensation of Si and Ti alkoxides (tetraethoxysilane and titanium tetrabutoxide) in the THF solution of a hydrophobic polymer, ethyl cellulose. Their structure and properties are studied with the use of a complex of physicochemical methods. During the hydrolysis of tetraethoxysilane and the subsequent polycondensation of the reaction products, silicon atoms are incorporated into the polymer and form -O-Si-O-bonds involving hydroxyl groups of ethyl cellulose. In the sol-gel method, titanium alkoxide yields nanosized particles of titanium dioxide that play the role of fillers in the polymer matrix. Titanium-containing films show solubility in THF and, after prolonged contact with the solvent, precipitate titanium dioxide from the solution. Hybrid films containing silicon are insoluble owing to the formation of a chemical network between polymer molecules and Si-OH groups of the products of hydrolysis of silicon alkoxide, as confirmed by the IR data. It is shown that the amounts and types of alkoxides and the diameters of the structures formed in the polymer matrix via the sol-gel procedure affect the hydrophilicity levels of ethyl cellulose hybrid films and their abilities to swell in water and aqueous solutions of organic dyes (brilliant blue and methylene blue). Ethyl cellulose hybrid films are hydrophilic, and they facilitate the removal of dye molecules from aqueous solutions. The best properties are featured by the films containing nanosized particles of titanium dioxide in the polymer matrix. © 2013 Pleiades Publishing, Ltd

International educational migration as a “soft power resource” in the globalization era

The international educational migration as a resource of «soft power» of the state has been analyzed in the article. Based on comprehensive analysis of the existing definitions of educational migration the author’s interpretation of this concept have been proposed. Based on the data of UNESCO, the Institute of international education of the United States, the Ministry of Science and Higher Education of the Russian Federation the statistics of international educational migration has been presented and analyzed. The main emphasis has been made on such categories of international educational migrants as students (bachelors, masters), postgraduate students. The reasons for the popularity of foreign students in countries such as Canada and the United States have been described. Based on the study two groups of factors have been highlighted: external and internal (motivational) factors, influencing decision-making in choosing the country of study.Based on the data of the Ministry of Science and Higher Education of the Russian Federation, the advantages of education in Russia have been analyzed. The issue of adaptation of foreign students in Russian universities has been considered: first-year curatorial programs, the Institute of student fellowships. It has been concluded hat Russian universities have a wealth of experience in teaching and adaptation of foreign students.The concepts and projects to attract foreign students to the Russian Federation also have been described in detail. Special attention to two projects “5–100” and “Export of Russian education” has been paid. The Federal Agency for the Commonwealth of Independent States Affairs, Compatriots Living Abroad, and International Humanitarian Cooperation (Rossotrudnichestvo) as one of the main institutions in the export of Russian education has been designated. The measures to attract foreign students to Russian universities have been proposed

Climatic variability of the mean flow and stationary planetary waves in the NCEP/NCAR reanalysis data

NCEP/NCAR (National Center for Environmental Prediction – National Center for Atmospheric Research) data have been used to estimate the long-term variability of the mean flow, temperature, and Stationary Planetary Waves (SPW) in the troposphere and lower stratosphere. The results obtained show noticeable climatic variabilities in the intensity and position of the tropospheric jets that are caused by temperature changes in the lower atmosphere. As a result, we can expect that this variability of the mean flow will cause the changes in the SPW propagation conditions. The simulation of the SPW with zonal wave number <I>m</I>=1 (SPW1), performed with a linearized model using the mean flow distributions typical for the 1960s and for the beginning of 21st century, supports this assumption and shows that during the last 40 years the amplitude of the SPW1 in the stratosphere and mesosphere increased substantially. The analysis of the SPW amplitudes extracted from the geopotential height and zonal wind NCEP/NCAR data supports the results of simulation and shows that during the last years there exists an increase in the SPW1 activity in the lower stratosphere. These changes in the amplitudes are accompanied by increased interannual variability of the SPW1, as well. Analysis of the SPW2 activity shows that changes in its amplitude have a different sign in the northern winter hemisphere and at low latitudes in the southern summer hemisphere. The value of the SPW2 variability differs latitudinally and can be explained by nonlinear interference of the primary wave propagation from below and from secondary SPW2

Influence of Employments an Athletics Gymnastics on Physical Preparedness of Students of Senior Classes

У статті проаналізовано методичні підходи до побудови занять атлетичною гімнастикою з учнями старших класів, визначено вплив засобів атлетичної гімнастики на фізичну підготовленість школярів. In the articles the exposed methodical going near the construction of employments an athletics gymnastics with the students of senior classes, influence of facilities of athletics gymnastics is certain on physical preparedness of students

Structured Au/FeOx/C catalysts for low temperature CO oxidation

Innovative structured catalysts based on nanoparticles of gold supported on activated carbon fibers (ACF) in the form of woven fabrics are presented for low-temperature CO oxidation. Gold was deposited by adsorption from aqueous solution of ethylenediamine complex [Au(en)2]Cl3 followed by reduction in hydrogen. The catalysts were studied under transient reaction conditions and characterized by high-resolution transmission electron microscopy (HRTEM) and X-ray energy dispersive analysis (EDS). HRTEM-EDS shows that gold is present on the surface of Au/ACF catalyst in the form of metallic particles with sizes of ~2.5–5 and ~30–50 nm. A predeposition of iron oxide on the ACF was beneficial for the Au dispersion and catalytic activity in CO oxidation. Gold particles in the Au/FeOx/ACF samples were not in direct contact with the Fe2O3 phase and their size was smaller than without doping by iron oxide. The mechanism of catalyst formation, its morphology, and the influence of preparative conditions are discussed. The activity of Au/FeOx/ACF was substantially higher as compared to Au/Al2O3 and Au/FeOx/Al2O3 catalysts. A reductive pretreatment with H2 was necessary to activate the catalyst, but the activity decreased rapidly in CO/O2 atmosphere. Addition of hydrogen or water vapors to the reaction mixture increases the catalyst activity