Impact of Alkali Ions Codoping on Magnetic Properties of La(0.9)A(0.1)Mn(0.9)Co(0.1)O(3) (A: Li, K, Na) Powders and Ceramics

The aim of the work was to check how the introduction of alkali and cobalt ions into a manganese structure can affect the structural disorder and, in consequence, lead to the changes (improvements) of magnetic properties. The high-pressure sintering technique was applied to check if the external factor can modify the magnetization of manganites. Nanocrystalline La0.9A0.1Mn0.9Co0.1O3 (where A is Li, K, Na) powders were synthesized by the combustion technique. The respective powders were used for nanoceramics preparation by the high-pressure sintering technique. The structure and morphology of the compounds were studied by X-ray powder diffraction, scanning electron microscopy and energy-dispersive X-ray spectroscopy. Magnetization studies for all compounds were performed in order to check the changes induced by either codoping or the sintering pressure. It was found that the type of the dopant ion and sintering pressure produced significant changes to the magnetic properties of the studied compounds. Alkali ions lead to the stabilization of Co ions in the +2 oxidation state and the formation of positive exchange interactions Mn3+–Mn4+ and Co2+–Mn4+ and the subsequent increase in remanent magnetization. High sintering pressure leads to a decrease in grain size and reduction of long-range ferromagnetic order and lower magnetization. © 2020 by the authors. Licensee MDPI, Basel, Switzerland.This project has received funding from the European Union’s Horizon 2020 research and innovation programme under the Marie Skłodowska‐Curie grant agreement No 778070–TransFerr–H2020‐MSCA‐RISE‐ 2017. Part of this work was developed within the scope of the project CICECO‐Aveiro Institute of Materials, UIDB/50011/2020 and UIDP/50011/2020, financed by national funds through the Portuguese Foundation for Science and Technology/MCTES. The equipment of the Ural Center for Shared Use “Modern nanotechnology” UrFU was used. The work has been supported in part by the Ministry of Science and Higher Education of the Russian Federation under Project № FEUZ‐2020‐0054

Morphotropic phase boundary in Sm-substituted BiFeO3 ceramics: Local vs microscopic approaches

Samarium substituted bismuth ferrite (BiFeO3) ceramics prepared by sol-gel synthesis method were studied using both local scale and microscopic measurement techniques in order to clarify an evolution of the crystal structure of the compounds across the morphotropic phase boundary region. X-ray diffraction analysis, transmission and scanning electron microscopies, XPS, EDS/EDX experiments and piezoresponse force microscopy were used to study the structural transitions from the polar active rhombohedral phase to the anti-polar orthorhombic phase and then to the non-polar orthorhombic phase, observed in the Bi1−xSmxFeO3 compounds within the concentration range of 0.08 ≤ x ≤ 0.2. The results obtained by microscopic techniques testify that the compounds in the range of 0.12 ≤ x ≤ 0.15 are characterized by two phase structural state formed by a coexistence of the rhombohedral and the anti-polar orthorhombic phases; two phase structural state observed in the compounds with 0.15<x<0.18 is associated with a coexistence of the anti-polar orthorhombic and the non-polar orthorhombic phases. Local scale measurements have revealed a notable difference in the concentration range ascribed to the morphotropic phase boundary estimated by microscopic measurements, the obtained results testify a wider concentration range ascribed to a coexistence of different structural phases, the background of the mentioned difference is discussed. © 2021 Elsevier B.V.This work was supported by the European Union’s Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie grant agreement No. 778070 . M.V.S acknowledges Ministry of Science and Higher Education of the Russian Federation within the framework of state support for the creation and development of World-Class Research Centers “Digital biodesign and personalized healthcare” №075-15-2020-926 . Diffraction measurements and analysis (A.A.D. and D.V.K.) were supported by RFBR (projects # 20-58-00030 ) and BRFFR (project # F20R-123 ). Piezoresponse force microscopy investigations were made possible by the Russian Science Foundation (grant 19-72-10076 ). The equipment of the Ural Center for Shared Use “Modern nanotechnology” UrFU was used

Locational conflict and the siting of nuclear waste disposal repositories: an international appraisal

The industrialized nations of the world have begun to plan for the storage and eventual disposal of their increasing volumes of nuclear wastes. In this paper the authors inventory the progress made by these nations in planning for nuclear waste disposal. A typology based on the adoption of spent-fuel reprocessing programs and of progress toward selection of permanent disposal sites is developed, and the world's nuclear nations are located within this typology. However, those countries which have been active in determining and constructing disposal sites have faced considerable internal and international political conflict. Conflict over nuclear waste disposal site-selection is both a geographical and a political problem. There is a review of various factors which contribute to the articulation and resolution of political conflict, including public participation in siting decisions, veto power of local governments, and prospects for international cooperation in siting decisions. It is concluded that decentralized democratic procedures, which emphasize public participation in siting decisions, have the strongest potential for conflict resolution.

Residual stresses and clamped thermal expansion in LiNbO3 and LiTaO3 thin films

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Values in General Education School: Teachers’ Approach

Moral values are characterized as meaning of human life and plenitude condition. The basis of moral values are always spiritual and ensuring human as individual united becoming. The influence of moral values to better pupil achievements and thinking are based on academic research. Attention is drawn, that values of educators are related not only with their own work but also with ability to create more humane relations and educational process – to work with all age group students and base communication in educational process on self-esteem and creativity. The values of educators have an influence on student maturity – education based on moral values determine positive social behavior, allows the better understanding of behaviour impact on yourself and others, develop his ethic vocabulary. The research discovers that in modern school moral values are not frequent – they formed a quarter of all identified values. Values can be considered as aspect of organization of educational process, school management and work with parents. However by this way the attitude is expressed to school management and education based on humane relations, establishment of conditions is emphasized to correspond not only the need of educator but also the needs of other schools community members. Discussing values, educators often express problems arising while organizing educational process. So it must be assumed that various pedagogical difficulties have influence on value education – giving a sense to student activities require considerable amount of effort. Therefore short-term goals are set and pupil moral position is understood in school. Little attention to spiritual learning perspectives.Straipsnyje aptariama vertybinio ugdymo svarba bendrojo ugdymo mokykloje, analizuojama, kokioms vertybėms edukacinėje praktikoje skiriama didžiausia reikšmė. Atsiremiant į tai, kad dorovinės vertybės laikomos būtina žmoniškumo prielaida, kad nepriklausomos Lietuvos švietimo sistema grindžiama dorovinėmis nuostatomis, straipsnyje analizuojamas pedagogų požiūris į dorovines vertybes bei jų formavimosi kontekstą