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Information × Registration Number 0212U002022, 0109U001452 , R & D reports Title Dinamical and structural processes in matters and multiscale modelling of materials on nano-, mezo- and macrolevels popup.stage_title Head Kuklin Volodimir Mihaylovich, Registration Date 12-01-2012 Organization Kharkov National University named after V.N. Karazin popup.description2 Object of study - alloys and materials at the nano-, meso- and macro-level structural elements multiscale objects, the hierarchical structures of different crystal objects, such as graphite, alloys and compounds based on molybdenum. The aim is the creation of physical concepts, principles, criteria and models for managing structural-phase state consolidated and condensed materials with properties that dynamically respond to changes in a wide range of parameters of radiation exposure. Methods of research - theoretical, aimed at development methods of description and study of the formation of bursts of interference spectra of excitement under the influence of the external pump. Theoretical studies have focused on the development of methods for describing the spectra of bursts of interference waves under the influence of the external pump Experimental methods for study of the evolution multiscale structures at the nano-, meso-, micro- and macro-level it possible to clarify the influence of external factors on the structural-phase state real objects (metals, alloys, ceramics and composites). As a result, experimental studies of the graphite surface by scanning tunneling microscopy detected periodic modulation of the surface electron density, small-scale nature of which such a modulation of the electron density within the elementary focus on the graphite surface. There is a different direction and multiscale nude elevation in the position of carbon atoms, even in the face of atomically clean surfaces or graphite. The increase of this difference in the presence of neighboring C atoms may be involved in explaining the initial stage of coagulation of carbon graphite sheet. We consider the development of modulation instability waves in a medium with absorption and in the presence of an external monochromatic source of vibrations. It is shown that in a small ratio of the amplitudes of individual modes of the spectrum to the amplitude of the fundamental wave can be confined to the interaction of the spectrum of modes supported by the fundamental wave. The appearance of anomalous large-amplitude waves characteristic of the initial stage of the modulation instability. With further development of the process can be observed the appearance of waves that satisfy the criterion of abnormality, but their amplitudes decrease gradually along with the average amplitude of the waves. The scientific novelty is that the first use of an unconventional approach to solving the new problem description of dynamical processes taking into account the perturbations of different spatial and temporal scales for the simulation of structural phase transitions and transformations (processes of structure formation and phase transitions). It is shown that when approaching a steady state of the spatial structure of trying to get rid of defects, determine the correlation between the relative shares of visually noticeable defects and defect size. At the initial stage of the modulation instability is characteristic of the formation of abnormal waves of large amplitude. The development of instability is accompanied by a decrease in the number of average and maximum wave amplitudes. Product Description popup.authors Кіріченко В. Куклін В. Литовченко С. Чишкала В. popup.nrat_date 2020-04-02 Close