1,539 research outputs found
Changes in the ratio of plants with different mycorrhizal status in the course of pasture digression in the Southern Ural steppes
Trends in the proportions of plants differently interacting with mycorrhizal fungi in the course of pasture digression have been analyzed in the steppe zone of the Southern Urals. Estimates of species richness and abundance of plant groups with different mycorrhizal status have been obtained by comparing original data on the structure of phytocenoses with published data on the ability of plant species to form mycorrhizae. It has been shown that the proportions and abundance of obligate mycorrhizal species decrease significantly in the course of digression, with consequent increase in those of species less dependent on or independent of symbiosis with fungi, i.e., facultative mycorrhizal or obligate nonmycorrhizal plants. © 2013 Pleiades Publishing, Ltd
Crystal structure and conductivity of bismuth-containing complex oxides
In the paper, a comprehensive systematic study of different classes of bismuth containing oxide compounds was carried out. The relationship between composition, temperature and concentration regions of existence of stable, specific structure and properties of solid solutions on the basis of vanadates, molybdates, niobates and bismuth was found. The general regularities of synthesis of solid solutions with different variants of solid-phase and soluble methods were determined. On this basis, the optimal conditions for obtaining
single-phase materials were formulated. For the first time the temperature and concentration boundaries of the regions of homogeneity and areas of stable existence of polymorphic modifications of solid solutions were defined and/or refined. The structural parameters of the synthesized phases were determined. By the method of electrochemical impedance spectroscopy the nature and features
of impedance spectra, the temperature and concentration dependences of electrical conductivity of ceramic materials based on bismuth containing complex oxides were identified
Preparation and characterization of Bi26–2xMn2xMo10O69-d and Bi26.4Mn0.6Mo10–2yMe2yO69-d(Me = V, Fe) solid solutions
Received: 06.06.2017; accepted: 23.06.2017; published: 14.07.2017.Single phase samples of bismuth molybdate, Bi26Mo10O69, doped with Mn on the bismuth sublattice and V, Fe on the molybdenum sublattice were found to crystallize in the triclinic Bi26Mo10O69 structure at low doping levels and in the monoclinic Bi26Mo10O69 structure - at higher dopant concentration. The assumption that all Mn ions have an oxidation state of +2 was confirmed by means of magnetic measurement results analysis using Curie-Weiss law. Conductivity was investigated using impedance spectroscopy. The conductivity of Bi26.4Mn0.6Mo9.6Fe0.4O69-d was 1.2*10-2 S*cm-1 at 973 K and 2.2*10-4 S*cm-1 at 623 K, and the conductivity of Bi26.4Mn0.6Mo9.2V0.8O69-d was 2.2*10-3 S*cm-1 at 973 K and 2.2*10-5 S*cm-1 at 623 K
Tutorial-pictorial presentation of program codes in the python language for illustration of the flow chart theory principles
© Research India Publications. In this paper fragments of programs illustrating the principles of the flow chart theory by the example of the schemes of interpretation of interactive system script are presented. This paper describes the standard structural patterns of dialog interaction ‘human-computer’and provides the relevant program code for each of them in the Python language. As the interactive interaction patterns such patterns as ‘pattern of choice "to —> to + 1’("next")‘, ‘sequential interpretation of elements’, ‘pattern of the kind "if -then—else"», ‘pattern of "case" kind’, ‘pattern of "while—do" kind’, ‘pattern of "repeat — until" kind’, ‘pattern of “CALL” kind’are considered. The designed program codes may be used in the training courses ‘Theory of computing processes and structures’and ‘Design of a human-machine interface’. This paper represents the designed tutorial-pictorial presentation of principles of flow chart theory that may be used as the tutorial material for both of the specified courses
The Indicative Potential of the Forest-Tundra Landscape Component
In order to expand the possibilities of soil-cover remote monitoring and improve prognostic models of active-layer depth dynamics in connection with global climatic changes, the verification of correspondence between plant and soil components of subarctic landscapes is necessary. This is most relevant for the forest-tundra zone,where the variety and mosaicity of soils and vegetation is great due to its ecotonic position. The purpose of this work was to study the relationship of vegetation with the characteristics of cryogenic soils and the dynamics of the active layer in forest-tundra landscapes. Data were obtained during monitoring studies at key sites in diverse landscapes of forest-tundra in the vicinity of Labytnangi. It was revealed that the thickness of the organogenic horizons, as well as the value of the moss phytomass, determine the active-layer thickness. A close connection with relief and soils allows the use of vegetation as an indicator of the soil texture and the depth of active-layer occurrence and features.
Keywords: plant communities, cryogenic soils, active layer, landscape, forest-tundra, Western Siberi
ФИГУРЫ ТАНАТОСА И ЭРОСА В ПОЭТИКЕ А. С. ПУШКИНА
The article deals with ontological issues of creativity and mortal implied sense of Pushkin's fairy tale. The study object is the figures of Thanatos and Eros in ‘The Tale of the Golden Cockerel’ fairy tale. The images of King Dadon and the Queen of Shamakhan are revealed in symbiotic relationship with folklore aesthetics. Reference to folklore is caused not only by genre of the work but also by metaphysical nature of oral tradition since the Russian people have a special attitude to the theme of death. This is evidenced by the Russian fairy tale with search of “the other kingdom” in which a hero must suffer a temporary death in order to get a wonderful object, save a prophetic bride and obtain the sacred knowledge.El artículo trata sobre cuestiones ontológicas de la creatividad y el sentido implícito mortal del cuento de hadas de Pushkin. El objeto de estudio son las figuras de Thanatos y Eros en el cuento de hadas "El cuento del gallo de oro". Las imágenes del rey Dadon y la reina de Shamakhan se revelan en una relación simbiótica con la estética del folklore. La referencia al folclore es causada no solo por el género de la obra sino también por la naturaleza metafísica de la tradición oral, ya que el pueblo ruso tiene una actitud especial hacia el tema de la muerte. Esto se evidencia en el cuento de hadas ruso con la búsqueda del "otro reino" en el que un héroe debe sufrir una muerte temporal para obtener un objeto maravilloso, salvar a una novia profética y obtener el conocimiento sagrado.В статье рассматриваются онтологические вопросы творчества, мортальный подтекст пушкинской сказки. Предметом исследования выступают фигуры Танатоса и Эроса в «Сказке о золотом петушке». Образы царя Дадона и Шамаханской Царицы раскрываются в неразрывной связи с фольклорной эстетикой. Обращение к фольклору обусловлено не только жанром произведения, но и самой метафизической природой устного народного творчества, так как русский народ особым образом относится к теме смерти. Об этом свидетельствует и русская волшебная сказка с поисками «иного царства», в которой герой обязательно должен пережить временную смерть, чтобы добыть чудесный предмет, выручить вещую невесту, приобщиться к сакральным знаниям
Grain sizes and dislocation densities in fcc-metallic materials processed by warm to hot working
Our just received results on the deformation microstructures evolved in a mediumMn austenitic steel during large strain warm to hot rolling were analyzed with a reference to other alloys with face centred cubic lattices and relatively low stacking fault energies. The structural changes were characterized by the development of dynamic recovery (DRV) and dynamic recrystallization (DRX). The deformation grain size decreased while the dislocation density increased with a decrease in deformation temperatur
Formation of future specialists’ communicative competence in language disciplines through modeling in game of professional situations
The relevance of the research problem driven by the necessity of formation of future specialists’ communicative competence as a component of professional competence with the aim of further professional mobility of graduates. The purpose of the article is to justify the possibility and necessity of formation of the required competencies in language disciplines at the University through the simulation of professional situations in practical classes. Leading method to the study of this problem is empirical, allowing to reveal the modeling capabilities in the game of professional situations and the use of games as forms of work in the classroom. Different variants of the experimental materials are developed and tested: game situations on a professional theme, tests, assignments, exercises, questions, reference work, selection of texts on pedagogy and education in our country and in the country of the target language. The article can be useful in practical work, to the teachers of language courses, not only at the universities, but also at schools, colleges, as well as interesting to all who are connected with professional pedagogical activity. © 2016 Sturikova et al
NMR and LDA evidence for spiral magnetic order in the chain cuprate LiCu2O2
We report on {6,7}Li nuclear magnetic resonance measurements of the
spin-chain compound LiCu2O2 in the paramagnetic and magnetically ordered
states. Below T about 24 K the NMR lineshape presents a clear signature of
incommensurate (IC) static modulation of the local magnetic field consistent
with an IC spiral modulation of the magnetic moments. {7}Li NMR reveals strong
phason-like dynamical fluctuations extending well below 24 K. We hypothesize
that a series of phase transitions at 24.2, 22.5, and 9 K reflects a "Devil's
staircase" type behavior generic for IC systems. LDA based calculations of
exchange integrals reveal a large in-chain frustration leading to a magnetical
spiral.Comment: 4 pages, 4 figure
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