Charge ordering and interlayer phase coherence in quantum Hall superlattices

The possibility of the existence of states with a spontaneous interlayer phase coherence in multilayer electron systems in a high perpendicular to the layers magnetic field is investigated. It is shown that phase coherence can be established in such systems only within individual pairs of adjacent layers, while such coherence does not exist between layers of different pairs. The conditions for stability of the state with interlayer phase coherence against transition to a charge-ordered state are determined. It is shown that in the system with the number of layers N\leq 10 these conditions are satisfied at any value of the interlayer distance d. For N>10 there are two intervals of stability: at sufficiently large and at sufficiently small d. For N\to \infty the stability interval in the region of small d vanishesComment: 10 page

PHOTOTUNABLE SELECTIVE REFLECTION OF CHOLESTERIC LIQUID CRYSTALS

The dependence of the helical pitch of a cholesteric liquid crystal based on a composite photosensitive chiral dopant (cChD) on the intensity of light irradiation was studied. The transmission spectra and the selective reflection spectra of cholesteric liquid crystal cells were measured. The concentration of the cChD additive is calculated, so that the peak of selective reflection and its rearrangement occurs in the visible range of the electromagnetic radiation spectrum (380-780 nm). The possibility of photo-control by shifting the peak of the selective reflection of the cChD additive was studied, when exposed to LEDs with wavelengths of 365 nm and 450 nm, while reducing or increasing the intensity, a change in the spiral pitch was observed. Depending on the light intensity, part of the molecules of the chiral additive containing the azo group underwent isomerization, i.e. molecules in the trans-form passed to the cis-form, which led to a spectral shift of the selective reflection peak. If a small intensity of the 365 nm LED was applied, then some of the molecules were forced to transition from the trans- to the cis-form, and then, when illuminated with a 450 nm LED, from the cisto the trans-form. After reversible rearrangement, the properties of cholesteric liquid crystal changes due to interaction with light, because under the influence of light, the equilibrium ratio of the trans- and cis-isomers of the molecules of the substance changed, which macroscopically changed the torsion force of the chiral additive. Using two LEDs of 365 nm and 450 nm with different emission spectra, a reversible control of the cChD selective reflection peak in the visible range was obtained. The maximum displacement occurred at approximately 145 nm.The dependence of the helical pitch of a cholesteric liquid crystal based on a composite photosensitive chiral dopant (cChD) on the intensity of light irradiation was studied. The transmission spectra and the selective reflection spectra of cholesteric liquid crystal cells were measured. The concentration of the cChD additive is calculated, so that the peak of selective reflection and its rearrangement occurs in the visible range of the electromagnetic radiation spectrum (380-780 nm). The possibility of photo-control by shifting the peak of the selective reflection of the cChD additive was studied, when exposed to LEDs with wavelengths of 365 nm and 450 nm, while reducing or increasing the intensity, a change in the spiral pitch was observed. Depending on the light intensity, part of the molecules of the chiral additive containing the azo group underwent isomerization, i.e. molecules in the trans-form passed to the cis-form, which led to a spectral shift of the selective reflection peak. If a small intensity of the 365 nm LED was applied, then some of the molecules were forced to transition from the trans- to the cis-form, and then, when illuminated with a 450 nm LED, from the cisto the trans-form. After reversible rearrangement, the properties of cholesteric liquid crystal changes due to interaction with light, because under the influence of light, the equilibrium ratio of the trans- and cis-isomers of the molecules of the substance changed, which macroscopically changed the torsion force of the chiral additive. Using two LEDs of 365 nm and 450 nm with different emission spectra, a reversible control of the cChD selective reflection peak in the visible range was obtained. The maximum displacement occurred at approximately 145 nm

«Axiological Turn» in Russian Education: Position of Subjectivism

Reflective theorizations about the state and prospects for the development of domestic education clearly recognize two trends in its future – continuity and individualization. In addition, the tendency of an “axiological turn” in the sense of education as a value and the value of education itself is clearly articulated. Modern pluralism of educational practices indicates the possibility of an individual to become the main subject of a new type of educational interaction based on independent institutionalization. Does the trend of “axiological turn” have ontological grounds for the sanctioned possibility of free change in the subjectivity of an individual in the educational space on fundamentally new methodological grounds? Or is it a continuation of the methodological tradition of axiological subjectivism? In order to find the foundations of a new axiological tradition in the educational space, a theoretical formalization of the category of “value” in the historical and philosophical tradition is being developed, and the results of this formalization are projected onto modern Russian education.On the one hand, the interpretation of educational values as skills, abilities and competencies is nothing more than an objective requirement of a dynamically changing socio-cultural situation with its ever-increasing uncertainty. On the other hand, the “axiological turn”, to a much greater extent, is associated with a change in the value orientations of the individual him/herself. This, with a special degree of efficiency and dynamism, is expressed in a change in the nature of educational-individual trajectories towards the professionalization of educational practices with a simultaneous strengthening of their meta-component. It is emphasized that meta-skills, along with existential skills, are the general vectors in the development of the axiological ecosystem of education. Based on the historical and philosophical review of the understanding of values and ideas about education as a way of reproducing culture (in the dialectic of alienation and appropriation of social values), the conclusion is formulated that modern concepts of the reversal of educational practices are, to a certain extent, private explications of axiological subjectivism

The concept of personal identity in modern socio-philosophical discourse: theoretical and methodological aspect

Relevance: The article is devoted to the socio-philosophical comprehension of the personal identity problem in the Internet. The situation of our time, characterized by “fluidity,” the variability of self-images, “masks”, has a resemblance to virtual space, which allows the individual to “try on” various social roles. The problem of personal identity requires a socio-philosophical understanding in the modern world. Purpose: to reflect the modern vision of sociologists and philosophers of the concept of personal identity, to identify the main characteristics of personal identity on the Internet. Methods of research: The theoretical and methodological basis of the study is the structural and constructivist approach. This approach is based on the conception that identities are the construct of the personality itself, they can be transformed depending on the individual’s choice, while the structure of society is determined by the identities system. The main results: A modern individual can be described as an individual of mass information consumption. The study of modern socio-philosophical works of the concept of personal identity allows us to determine the following characteristics: variability associated with social context; procedural nature; structure planning; reflexivity; categorization; selection. Scientific novelty of the study lies in the author’s position, according to which the key characteristics of personal identity include: variability related to the social context; procedural nature; construction; categorization; choice. Directions for future research: in further research, the problem of personal identity in the conditions of Internet communication will be considered by us in the context of the dichotomies “private-public”, “I-Other”, which will make it possible to understand how personal identity is formed and transformed in the modern Internet

Non-LTE abundances of zinc in different spectral type stars and the Galactic [Zn/Fe] trend based on quantum-mechanical data on inelastic processes in zinc-hydrogen collisions

We present a new model atom of Zn I-II based on the most up-to-date photoionisation cross-sections, electron-impact excitation rates, and rate coefficients for the Zn I + H I and Zn II + H- collisions. The latter were calculated using the multi-channel quantum asymptotic treatment based on the Born-Oppenheimer approach. Non-LTE analysis was performed for the first time for lines of Zn I and Zn II in the ultraviolet (UV) spectra of two very metal-poor reference stars, HD 84937 and HD 140283. We found consistent non-LTE abundance from the resonance Zn I 2138 A line, the subordinate lines, and the lines of Zn II. In both stars, non-LTE leads to 0.17 dex higher average abundance from Zn I, while, for Zn II lines, non-LTE corrections are minor and do not exceed 0.06 dex. Using lines of Zn I in the high-resolution spectra, we determined the non-LTE abundances for a sample of 80 stars in the -2.5 < [Fe/H] < 0.2 metallicity range. The [Zn/Fe] versus [Fe/H] diagram reveals a dip, with [Zn/Fe] = 0.3 in the most metal-poor stars, a close-to-solar value for [Fe/H] = -1.2, and increasing [Zn/Fe] up to 0.3 in the thick disk stars. The close-to-solar metallicity stars have subsolar [Zn/H] = -0.1, on average. Non-LTE abundances of zinc were derived for the first time for seven reference F to B-type stars. We provide a grid of the non-LTE abundance corrections.Comment: 15 pages, 9 figures, accepted to MNRA

Evolution of the texture of low-carbon microalloyed pipe steel in the seamless pipe manufacturing process

A method of orientation microscopy (with the application of the EBSD technique) is used in investigation of the microstructure and texture in steel 0.08 % C-Cr-Mo-V formed at different stages of the seamless pipe manufacturing process, namely, after hot finishing and after full quenching with subsequent high-temperature tempering. It is shown that, at the final stage of hot finishing followed by heat treatment, the texture is represented by four scattered orientations. The found texture inheritance in the investigated material is presumably related to reproduction of special circa Σ3 boundaries between crystal grains at each phase transition. © 2016 Author(s)