H-T Phase Diagram of Rare-Earth -- Transition Metal Alloy in the Vicinity of the Compensation Point

Anomalous hysteresis loops of ferrimagnetic amorphous alloys in high magnetic field and in the vicinity of the compensation temperature have so far been explained by sample inhomogeneities. We obtain H-T magnetic phase diagram for ferrimagnetic GdFeCo alloy using a two-sublattice model in the paramagnetic rare-earth ion approximation and taking into account rare-earth (Gd) magnetic anisotropy. It is shown that if the magnetic anisotropy of the $f$-sublattice is larger than that of the $d$-sublattice, the tricritical point can be at higher temperature than the compensation point. The obtained phase diagram explains the observed anomalous hysteresis loops as a result of high-field magnetic phase transition, the order of which changes with temperature. It also implies that in the vicinity of the magnetic compensation point the shape of magnetic hysteresis loop is strongly temperature dependent.Comment: 8 pages, 3 figure

Selection Rules for All-Optical Magnetic Recording in Iron Garnet

Finding an electronic transition a subtle excitation of which can launch dramatic changes of electric, optical or magnetic properties of media is one of the long-standing dreams in the field of photo-induced phase transitions [1-5]. Therefore the discovery of the magnetization switching only by a femtosecond laser pulse [6-10] triggered intense discussions about mechanisms responsible for these laser-induced changes. Here we report the experimentally revealed selection rules on polarization and wavelengths of ultrafast photo-magnetic recording in Co-doped garnet film and identify the workspace of the parameters (magnetic damping, wavelength and polarization of light) allowing this effect. The all-optical magnetic switching under both single pulse and multiple-pulse sequences can be achieved at room temperature, in narrow spectral ranges with light polarized either along or crystallographic axes of the garnet. The revealed selection rules indicate that the excitations responsible for the coupling of light to spins are d-electron transitions in octahedral and tetrahedral Co-sublattices, respectively

High Field Anomalies of Equilibrium and Ultrafast Magnetism in Rare-Earth-Transition Metal Ferrimagnets

Magneto-optical spectroscopy in fields up to 30 Tesla reveals anomalies in the equilibrium and ultrafast magnetic properties of the ferrimagnetic rare-earth-transition metal alloy TbFeCo. In particular, in the vicinity of the magnetization compensation temperature, each of the magnetizations of the antiferromagnetically coupled Tb and FeCo sublattices show triple hysteresis loops. Contrary to state-of-the-art theory, which explains such loops by sample inhomogeneities, here we show that they are an intrinsic property of the rare-earth ferrimagnets. Assuming that the rare-earth ions are paramagnetic and have a non-zero orbital momentum in the ground state and, therefore, a large magnetic anisotropy, we are able to reproduce the experimentally observed behavior in equilibrium. The same theory is also able to describe the experimentally observed critical slowdown of the spin dynamics in the vicinity of the magnetization compensation temperature, emphasizing the role played by the orbital momentum in static and ultrafast magnetism of ferrimagnets

Educational research networks principles of organization

Relevance. Modern society has global transformations; as a result, the level characteristics of its system development are changing, new opportunities and new situations to implement a self-organizing system to solve problems of self-government appear. Thus, there is the need to organize the multiplicity of interactions in the new environment, including education. The success of the development mechanisms, organizing innovative activities in the educational systems of different levels is largely determined by the active development of interaction network forms and interaction effective management. The article is devoted to development of theoretical ideas about the processes of network interaction in education to justify and describe the principles of modern scientific-educational network on the basis of system-synergetic approach. A leading approach to study this problem can be considered as system-synergetic which allows studying network interaction within the scientific and educational network as a holistic entity consisting of interrelated elements, structured and complex. The results of the study showed that described principles of effective networking and the conditions of scientific and educational networks development allow you to combine and re-combine the accumulated actors of this knowledge and practical experience interaction, turning them into the means of its innovative activities. The article can be useful to heads of educational institutions of different levels, as well as researchers of innovative processes development problems in education. © 2018 Authors

Broadband dielectric spectroscopy on benzophenone: alpha relaxation, beta relaxation, and mode coupling theory

We have performed a detailed dielectric investigation of the relaxational dynamics of glass-forming benzophenone. Our measurements cover a broad frequency range of 0.1 Hz to 120 GHz and temperatures from far below the glass temperature well up into the region of the small-viscosity liquid. With respect to the alpha relaxation this material can be characterized as a typical molecular glass former with rather high fragility. A good agreement of the alpha relaxation behavior with the predictions of the mode coupling theory of the glass transition is stated. In addition, at temperatures below and in the vicinity of Tg we detect a well-pronounced beta relaxation of Johari-Goldstein type, which with increasing temperature develops into an excess wing. We compare our results to literature data from optical Kerr effect and depolarized light scattering experiments, where an excess-wing like feature was observed in the 1 - 100 GHz region. We address the question if the Cole-Cole peak, which was invoked to describe the optical Kerr effect data within the framework of the mode coupling theory, has any relation to the canonical beta relaxation detected by dielectric spectroscopy.Comment: 11 pages, 7 figures; revised version with new Fig. 5 and some smaller changes according to referees' demand

DEVELOPMENT OF FUNCTIONAL BEVERAGES FROM PLANTRAW MATERIALS — REPLACEMENTS FOR DAIRY PRODUCTS

Nowadays, there is a growing consumer interest in food products, made from vegeta-ble raw materials. The article is devoted to an actual topic related to the choice of plant mate-rials, based on its nutritional and biological value, in order to create functional beverages. The analysis of the world market of vegetable analogues of milk was implemented. Based on the literature, the following raw materials were analyzed: cashew nuts, cannabis fruits, sesame and poppy seeds, almond kernels, buckwheat seeds and oats, soybeans. The data on nutritional value, vitamin-mineral and amino acid composition, as well as the composition of fatty acids of the specified raw materials was presented. The conclusion is made about the perspective of its use for the manufacture of drinks, alternative cow’s milk. The article reflects the results of research work on the creation of a functional drink based on sesame seeds, provides information about the nutritional value and biochemical composition of the drink, made on the basis of this raw material. Sesame milk when used regularly can help prevent diseases of the car-diovascular system, the gastrointestinal tract, the musculoskeletal system.Nowadays, there is a growing consumer interest in food products, made from vegeta-ble raw materials. The article is devoted to an actual topic related to the choice of plant mate-rials, based on its nutritional and biological value, in order to create functional beverages. The analysis of the world market of vegetable analogues of milk was implemented. Based on the literature, the following raw materials were analyzed: cashew nuts, cannabis fruits, sesame and poppy seeds, almond kernels, buckwheat seeds and oats, soybeans. The data on nutritional value, vitamin-mineral and amino acid composition, as well as the composition of fatty acids of the specified raw materials was presented. The conclusion is made about the perspective of its use for the manufacture of drinks, alternative cow’s milk. The article reflects the results of research work on the creation of a functional drink based on sesame seeds, provides information about the nutritional value and biochemical composition of the drink, made on the basis of this raw material. Sesame milk when used regularly can help prevent diseases of the car-diovascular system, the gastrointestinal tract, the musculoskeletal system

Oral agreement juridical technique at the stage of contract signing: features and composition

Objective: to analyze the oral contractual legal technique and its component tools, to identify the features of technical and legal tools used at the stage of negotiating a contract.Methods: the dialectical approach to cognition of the legal phenomenon, allowing to analyze it from the point of view of the general theory of law, knowledge of individual branches of law and humanities; formal legal method (analysis of doctrinal provisions and practice of contractual law application), analysis, synthesis, comparison, classification, and other general scientific methods of cognition.Results: based on the analysis of theoretical and legal structures, legislation and practice of its application, conclusions are drawn about the existence of oral contractual legal technology and the criteria for distinguishing its legal tools from those of a non-legal nature. The legal tools of oral contractual legal techniques are expressed in the presence of specific rules for performing certain legally significant actions. These rules are characterized by: a) relative stability; b) direct focus on generating the main legal result: the emergence of rights and obligations in order to meet certain needs of the parties; c) dependence of the tools on the content of the contractual process stage. By the example of negotiating a contract as an important stage of the contractual process, one may regard good faith as the most significant rule in negotiations. The general model of signing a contract is also stable (sending a proposal to sign a contract, agreeing/disagreeing with the offer/agreeing to change the terms of the offer, sending a response to the offer, and signing the contract as a result). Negotiations can be organized in two ways: a) directly (based on the general provisions of Chapter 28 of the Russian Civil Code) and b) step-by-step (by signing an agreement on the procedure for conducting negotiations).Scientific novelty: oral contractual legal techniques rarely become the subject of scientific research. The proposed approach to the analysis of its tools is new for the Russian theory of legal technique.Practical significance: the main provisions and conclusions of the article contribute to the development of the legal technique theory aimed at improving the methods of professional legal activity, including in the field of contract signing

Research and educational network: Development management

Relevance of the study is determined by the fact that the management methodology of research and educational network development being of great interest for the improvement of the educational system, currently remains beyond the most scientific researches. Study purpose is aimed at the development of the organizational and pedagogical management model of research and educational network development in the field of education. Leading theoretical method of the research is the structural and functional approach enabling comprehensive consideration of the contents of the main components of the developing research and educational network and dependencies between them. The article presents the organizational and pedagogical management model of the developing research and educational network, describing the objectives, principles of participants’ interaction, functions, and structural networking components, revealing the scope of the activity, conditions, forms and types of the interaction. Materials may be useful to explore the possibilities of development of the intellectual capital of the subjects of network communication; training of specialists qualified in the field of generation and spread of new knowledge in the creation and development of research and education network. © 2016 Davydova et al