Dependence of the microstructure and magnetic properties of amorphous TbFeCo films on the type and pressure of the gas in sputtering

Amorphous Tb30Fe60Co10 films have been fabricated by magnetron sputtering. The dependences of the microstructure and magnetic properties of these films on the type and pressure of the gas in the sputtering chamber have been studied. The pressure of the Ar, Kr, and Xe gases used in the experiments is varied in the sputtering chamber from 0.01 to 4.00 Pa. It has been established that sputtering in the heavy gas (Kr) conducted within the pressure range covered does not permit fabricating TbFeCo films with the easy magnetization axis perpendicular to the film plane. With Xe used at pressures below 1.0 Pa, one observes in TbFeCo films an increase of the coercivity, with the hysteresis loop approaching rectangular shape. Sputtering and deposition in Ar at a pressure of ~0.67 Pa result in the formation of amorphous Tb30Fe60Co10 films with magnetic characteristics satisfying the requirements imposed upon information carriers intended to be employed in perpendicular recording. It has been demonstrated that, by magnetron sputtering in an Ar atmosphere performed at pressures below 1 Pa, one can produce amorphous Tb30Fe60Co10 films suitable for magneto-optical ultra-high-density information recording. © 2012 Pleiades Publishing, Ltd

Interactive Web 2.0 tools in content and language integrated learning (CLIL)

In modern world, teachers and educators have to work in the linguistically inhomogeneous audience of pupils and students, most of whom are bilinguals. Various models of bilingual education have their own specifics related to the peculiarities of the country, its history, culture, economic status, language status and mentality of the nation. In the past 20 years the technology of Content and Language Integrated Learning (CLIL) has become widespread in the European Union, which is used for teaching bilinguals. In the Republic of Tatarstan high school graduates with the Tatar language of education, after having entered higher education institutions, are faced with cognitive and linguistic difficulties, so the use of the technology of CLIL for bilingual education in universities of the Republic of Tatarstan is actual. Studying the experience of the application of CLIL in European universities of technology led to the conclusion that the most difficult in its realization is the development of teaching materials. The aim of the study was to develop teaching materials for use in the process of learning the Tatar-speaking students with the help of educational technology CLIL at university. We have developed the educational materials in computing based on Wikia and conducted educational experiment how to use them. The students of the Department of Tatar philology and culture of the Kazan Federal University took part in the experimental and control groups. The educational experiment was attended by 50 students, the experimental group - 25, control group -25 learners. The educational experiment was carried out for one semester of the academic year 2015/16. In teaching of the subject "Informatics" (36 hours) in the experimental group there were used the technology of CLIL and Web 2.0-based teaching materials. Informatics teaching in the control group was realized in Russian by means of traditional methods. The students were tested at the final stage of educational experiment. Processing of the results with the help of statistical methods led to the conclusion that the positive changes in the experimental group are due to CLIL-assisted training using teaching materials developed on the basis of Web 2.0 technologies

Electrocatalytic determination of dithiocarbamate-based pesticides using electrodes modified with metal phthalocyanines

An electrocatalytic method has been proposed for determining dithiocarbamate-based pesticides (carbathion, nabam, ferbam, thiram, and thiuram) using a carbon-paste electrode modified with iron(II) and cobalt(II) phthalocyanines. The first wave of carbathion oxidation in botli aqueous and organic solutions does not change compared to an unmodified carbon-paste electrode; for the second stage of oxidation, a decrease by 100 mV in the overpotential and a significant increase in the current are observed. The electrochemical signal is observed in the range of potentials characteristic for the oxidation of metal phtlialocyanines, and the metal phthalocyanine serves as the electron carrier. A similar effect is observed for the electrochemical oxidation of nabam. The catalytic activity of the metal phtlialocyanines to ferbam, thiram, and thiuram in acetone has been determined. In the case of the electrochemical oxidation of ziram and zineb, the electrocatalytic effect is not observed. The dependence of the peak current on the pesticide concentration is linear within the range from 1 × 10-3 to 1 × 10-7 M. The adsorption preconcentration of pesticides decreases the limit of detection by an order of magnitude. © 2001 MAIK "Nauka/Interperiodica"

Magnetic microstructure of oxygen-deficient perovskites

Samples of oxygen-deficient perovskites were studied by means of Mossbauer spectroscopy. The Mossbauer spectra were obtained at room temperature. X-ray data confirmed the ordered distribution of iron and copper deduced from Mossbauer spectroscopy data

Mössbauer study of some perovskite-related oxides

Complex perovskite-related oxides with various structure types: orthoferrites, 4-1-5, 8-8-20, and 1-2-3 were studied using Mössbauer spectroscopy. Correlations between magnetic ordering of iron atoms and their structural coordination, as well as between oxygen deficiency and iron ion valence, were found. © 2006 by Allerton Press, Inc

Effect of the CrW sublayer on the structure and magnetic properties of thin FePt films

Multilayer Fe 55Pt 45(20 nm)/Pt(5 nm)/Cr 100 - xW x(80 nm)/glass structures, in which the Fe 55Pt 45 magnetic film has a face-centered tetragonal (FCT) structure of the L1 0 phase with the (001) texture, have been prepared using magnetron sputtering. The microstructure and texture of the FePt films have been studied as functions of the W content in the Cr 100 - xW x sublayer, where 0 < x < 25. It has been established that an increase in the W ion concentration leads to the formation of the (200) texture in the Cr 100 - x sublayer and to an increase in the Cr lattice constant. This is accompanied by a decrease in the temperature at which the facecentered cubic phase transforms into the FCT phase of the FePt films as a result of the increase in tensile stresses along the a axis. It has been found that the coercivity of FePt films deposited on CrW substrates increases with increasing W content in the Cr 100 - xW x sublayer because the CrW alloy thus formed precludes diffusion between the FePt film and the CrW sublayer. An additional 5-nm-thick intermediate Pt layer is also deposited to suppress diffusion between the FePt and CrW layers. As a result, the highly textured FePt(001) films intended for ultra-high density magnetic information recording are deposited on a substrate heated to a temperature of 400°C and the Cr 85W1 15 sublayer. © 2012 Pleiades Publishing, Ltd

Definition of development level of communicative features of mathematical speech of bilingual students

Lingual environment of Republic of Tatarstan (Russian Federation) is bilingual. Pupils in schools are being taught on two languages: Russia and Tatar. Some graduates of schools of Republic of Tatarstan study in the institutions of high education on bilingual base. The aim of research is to develop and apply definition criteria of development level of basic communicative features of mathematical speech of bilingual students

Synthesis of the aluminum-substituted hexaferrite SrFe 9.5Al 2.5O 19

The phase-formation processes involved in the synthesis of the hexagonal ferrite SrFe 9.5Al 2.5O 19 by solid-state reaction at 900°C for 5 min to 8 h were studied by x-ray diffraction and Mössbauer spectroscopy. The formation of the hexagonal ferrite at this temperature was found to take 3 h. The resultant material also contained SrAl 2O 4 and SrFeO 3-x, which suggests that, for the synthesis to reach completion, the heat-treatment temperature should be higher. The aluminum cations in the hexaferrite phase were shown to occupy, for the most part, positions 12k and 4f 1. © 1999 MAHK "Hayka/Interperiodica"

Electrocatalytic determination of oxalate ions on chemically modified electrodes

The electrocatalytic activity with respect to oxalate ions of spongy osmium immobilized within a carbon-paste electrode was studied. A procedure is proposed for electrocatalytic determination of oxalate ions on a chemically modified electrode based on spongy osmium under conditions of flow-through-injection analysis. © 2001 MAIK "Nauka/Interperiodica"

Effect of annealing in an external magnetic field on the microstructure and magnetic properties of the Fe/FePt/Pt multilayer system

The effect of annealing in an external magnetic field applied perpendicular to the plane of the film on the kinetics of Ll 0 phase transformation of the microstructure and the magnetic properties of the Fe(2 nm)/FePt(20 nm)/Pt(2 nm) multilayer system has been investigated. The relations between the hysteresis loop shape, magnetic correlation length, and structural disorders, which are characteristic of magnetic information carriers, have been analyzed. It has been found that the annealing of the Fe(2 nm)/FePt(20 nm)/Pt(2 nm) multilayer system at a temperature of 470°C in an external magnetic field of 3500 Oe, which is applied perpendicular to the film plane, leads to the formation of a face-centered tetragonal structure of the Ll 0 phase in the FePt film, which is characterized by the high coercivity H c, the (001) preferred texture, the magnetic anisotropy perpendicular to the film plane, small sizes of FePt grains in the film, and weak exchange coupling between the particles. The energy of the external magnetic field encourages the process of transformation of the FePt film into the Ll 0 phase. Thus, a method has been developed for fabricating multilayer films based on the FePt Ll 0 phase with the parameters necessary for information carrier materials with perpendicular-type magnetic recording. © 2012 Pleiades Publishing, Ltd