125 research outputs found

    НА ОБЛОМКАХ КОНСЕНСУСНЫХ СТРАТЕГИЙ XX ВЕКА. К ВОПРОСУ О ТЕОРЕТИЧЕСКИХ ОСНОВАНИЯХ КРИЗИСА СОЛИДАРИЗМА

    Get PDF
    The first decades of the XXI century have shown that mankind has once again suffered disappointment in optimistic forecasts, promising peace and harmony to the people. Increasingly, symptoms are manifested that contradict solidarity: increased distrust, centrifugal tendencies,  the desire to leave unions and associations, the growth of violence, the spread of the threat of terrorism – all this indicates the growth of destructive trends in the modern world. In this situation, reliance on force (whether hard or soft) seems much more preferable than trying to reach consensus. It is not surprising, therefore, that almost all theoretical models that focus on the rationale for consensus strategies, have faced a serious crisis of legitimacy if not lost their impact on real policies. The article analyzes the base theoretical foundations of the solidarity concepts of the second half of the twentieth century, identifies their vulnerable positions, which served as a target for criticism in modern political science and political philosophy, and traces the possible vectors of their transformation

    The study of titanium oxynitride coatings solubility deposited by reactive magnetron sputtering

    Get PDF
    To improve hemocompatibility of cardiovascular stents the coatings based on titanium oxides and oxynitrides were used. In the present work the morphology, surface properties (wettability and surface energy), and in vitro solubility of the ternary system Ti-N-O coating were investigated. Experimentally, low dissolution rate of the coating in saline NaCl (0,9%) was confirmed. Instrumental methods of quantitative analysis (XRF, AES) revealed that the Ti-N-O coating is chemical-resistant and does not change the qualitative and quantitative composition of body fluids

    Nanomechanical humidity detection through porous alumina cantilevers

    Get PDF
    Abstract We present here the behavior of the resonance frequency of porous anodic alumina cantilever arrays during water vapor adsorption and emphasize their possible use in the micromechanical sensing of humidity levels at least in the range of 10-22%. The sensitivity of porous anodic aluminium oxide cantilevers (Δf/Δm) and the humidity sensitivity equal about 56 Hz/pg and about 100 Hz/%, respectively. The approach presented here for the design of anodic alumina cantilever arrays by the combination of anodic oxidation and photolithography enables easy control over porosity, surface area, geometric and mechanical characteristics of the cantilever arrays for micromechanical sensing. 133

    Unveiling point defects in titania mesocrystals: a combined EPR and XPS study

    Get PDF
    Titania mesocrystals, prepared using a polyethylene template, were studied by a combination of electron microscopy, XPS and EPR techniques. The electronic structure and local environment of point defects in the TiO2 mesocrystals were deduced from experimental and simulated EPR data. The Ti3+/F centers and oxygen defects were shown to be the most photosensitive. The presence of carbon radicals was also demonstrated. Since the point defects govern TiO2 photosensitivity and photocatalytic activity in the visible spectral range, the data obtained provide new insights into photocatalytic reactions engineering using titania mesocrystal

    Polar and non-polar structures of NH4TiOF3

    Get PDF
    Ammonium oxo­fluoro­titanate, NH4TiOF3, is probably the best known precursor for the synthesis of anatase mesocrystals. Transformation of NH4TiOF3 into TiO2 through thermal decomposition, accompanied by hydrolysis, preserves some structural features of the precursor. Currently, any discussion of the mechanism of this transformation is difficult, as the exact crystal structure of the starting compound is not available and no intermediate structures are known. This article describes the outcome of single-crystal and powder X-ray diffraction studies, revealing the existence of two polymorphs of the parent NH4TiOF3 at different temperatures. A second-order phase transition from the polar Pca21 α phase (1), stable at room temperature, to the Pma2 β phase (2) above ∼433 K has been demonstrated. The direction of the pseudo-fourfold axis in NH4TiOF3 coincides with the orientation of the fourfold axis of anatase mesocrystals, consistent with a topotactical transformation

    The study of titanium oxynitride coatings solubility deposited by reactive magnetron sputtering

    Get PDF
    To improve hemocompatibility of cardiovascular stents the coatings based on titanium oxides and oxynitrides were used. In the present work the morphology, surface properties (wettability and surface energy), and in vitro solubility of the ternary system Ti-N-O coating were investigated. Experimentally, low dissolution rate of the coating in saline NaCl (0,9%) was confirmed. Instrumental methods of quantitative analysis (XRF, AES) revealed that the Ti-N-O coating is chemical-resistant and does not change the qualitative and quantitative composition of body fluids

    The effect of voluntary hypoventilation in yoga breathing exercises on gas exchange and EEG activity in healthy trained subjects

    Get PDF
    Objective: to assess the effect of voluntary hypoventilation during yoga breathing exercises on gas exchange and EEG activity in a group of healthy, trained practitioners.Materials and methods: 25 volunteers (21 men and 4 women, average age 42.96 ± 9.19 years) performed hypoventilation yoga exercises with a decrease in respiratory rate to 1–1.5 times/minute. Registration of respiratory rate, tidal volume and minute volume of breathing, gas analysis of exhaled air (PetCO2, FeO2) and spectral analysis of electroencephalogram (EEG) in gICA model were carried out during breathing with a frequency of 1–1.5 times/minute and during relatively free breathing with mental calculation.Results: Breathing with a frequency of 1–1.5 times/minute causes a decrease in minute volume of breathing, the development of alveolar hypoxia and hypercapnia, which leads to an increase in the power of some local components in the slow delta, theta and alpha EEG bands. In addition, breathing with a frequency of 1–1.5 times/minute is accompanied by a decrease in the alpha- and beta-power of some components, the sources of which are located in the motor areas of the cortex, but is also accompanied by an increase in the power of components with widespread scalp topography in beta and gamma bands.Conclusion: Voluntary hypoventilation during yoga breathing exercises leads to the development of alveolar hypoxia and hypercapnia, accompanied by an increase in the power of local components in the slow EEG bands. At the same time, the alpha and beta powers of components localized in the motor areas of the cortex decrease, which may be a consequence of muscle tension during slow breathing

    New insights into polymer mediated formation of anatase mesocrystals

    Get PDF
    The reaction between (NH4)2TiF6 and H3BO3 in the presence of varying quantities of PEG-6000 was used to form NH4TiOF3 mesocrystals (MCs). The amount of PEG-6000, employed as a template, is crucial to the formation of defect free, non-agglomerated NH4TiOF3 MCs; high concentrations lead to MC agglomeration, lower ones result in centralized defects. This polymer-mediated formation process may be understood using an analogy with known polymerization reactions. The oxofluorotitanate MCs readily undergo a thermal topotactic transformation to give anatase MCs with photocatalytic activity. The TiO2 MCs are porous, with highly orientated lamellar crystallites that form part of the larger mesocrystal structure
    corecore