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The present results of comprehensive researches of degradation processes for magnetron metal nanofilms of Ni and Cr when heated on air (373-1273 K) conducted by nanotechnology instruments. Temperatures of structural and phase transformations, interrelation of amplitude and phase-frequency components of ellipsometry measurements with "ferromagnetic-antiferromagnetic" for NiO phase transition are established [ABSTRACT FROM AUTHOR]

The paper analyzes the process of formation and subsequent deposition of monolayers stabilized in sodium oleate nanoparticles of barium titanate. X-ray diffractometer studies conducted particle size distribution of the ferroelectric particles deposited. Probe technique was used to study the effect of matter and the wettability of the underlayer on the structure and quality of deposited coatings. The possibility of recording ferroelectric domains produced thin Langmuir films of barium titanate. [ABSTRACT FROM AUTHOR]

Conducted macro-, micro- and nanostructured materials were investigated by the influence of sample sizes of steel 45 in the form of a parallelepiped, after intense static pulse processing in plastic deformation as in the single (150 J), and pulsed (25 J) impact with a frequency of 23 Hz. When all modes of processing bulk samples found structuring self-organized formation of dislocations. With a single exposure revealed as filling pearlite grains periodic dislocations (200 nm), and the formation of dislocation-free regions. When a periodic pulse treatment of the samples with transverse dimensions fold speed of propagation of elastic waves and shock waves as well as the related transport velocity of dislocations turns shockwave mechanism causing the formation of alternating strips of ferritic and pearlite walls (25 microns), wherein the pearlite wall completely or partially filled with dislocations. [ABSTRACT FROM AUTHOR]

The effectiveness and feasibility of producing nanoscale carbon materials from renewable bioresources were shown as an example marsh mass. The mechanisms of synthesis of amorphous organic carbon from sphagnum moss species modified by a liquid peat phase of humic nature are discussed. A fundamentally new way of producing carbon nanotubes by mechanical activation of amorphous organic carbon is described. [ABSTRACT FROM AUTHOR]

The influence of carbon black, red lead and polyaniline additives on the structure and functional characteristics of automotive lead-acid batteries has been studied. The mechanisms contributing to the formation both of lead dioxide by the introduction of these additives and of additional conductive nanostructured cross-linking channels in the case of polyaniline are described. [ABSTRACT FROM AUTHOR]

The results of micro- and nanoscale research of fractal structure sediments from mineral water received by the drop method are given. Qualitative analysis of the underlying physical phenomena, allowed us to establish the conditions of their 3D-fractalization that consider the size of colloidal nanoparticles, its location and height from the drop center : rmin = Rmax = hmax and rmax = Rmin = hmin. It is shown that the main contribution to 3D fractalization is due to surface tension forces and the Coulomb force interaction. [ABSTRACT FROM AUTHOR]

According to the analysis of the results of complex studies of mineral raw materials and man-handle products containing ultra-dispersed gold, silver, and platinum before and after laser treatment, a qualitative physical model which explains the origin of thermal processes occurring under the action of laser radiation is proposed. It is noted that laser treatment of those materials generates processes of defragmentation, thermocapillary extraction, and agglomeration of micro-and nanoinclusions of these metals. [ABSTRACT FROM AUTHOR]

Flexural elastic deformations of single-crystal silicon with microspectral Raman scattering are studied. The investigation results are given on nano-scaled sign-changing shifts of the main peak of the microspectral Raman scattering within the single-crystal silicon cantilever beam under influence of flexural stress. The maximum value of Raman shift characteristic of silicon peak equal to 518 cm-1, when elasticity still remains, amounted to 8 cm-1. The qualitative explanation of increase in strength of the cantilever beam due to its small thickness (2 μm) is provided, which is in accord with predictions of real-world physical parameters that were obtained in software environment SolidWorks with the module SimulationXpress. [ABSTRACT FROM AUTHOR]

The nanostructure and phase composition of the electrode material of lead-acid batteries, formed by chemical transformations with involvement of sulfuric acid solutions of various concentrations, water and carbon dioxide have been studied. [ABSTRACT FROM AUTHOR]

Processes of self-organization in diffusive and limited conditions of colloidal solutions of carbon nanotubes under the influence of constant electric fields are studied. It is established that functionalized MCNT - COOH in a drop of colloidal solution is oriented in an electric field in a controllable way, which is of great practical value. [ABSTRACT FROM AUTHOR]

The influence of the substrate temperature on the formation of high-temperature phases of hafnium dioxide in the process of pulsed laser ablation is investigated. It is established that the HfO2 nanoparticles of the high-temperature tetragonal and cubic phases with a quantitative content up to 50 % are formed on the surface of the substrate at room temperature during the laser ablation with intensity of 1010 W/m2. It is shown that with increasing the substrate temperature the average size of the ablated nanoparticles decreases and the quantitative content of the high-temperature phases is increased up to 70 %. [ABSTRACT FROM AUTHOR]

The present paper deals with the results of comprehensive research of heated in the air magnetron copper films by atomic-force and scanning electron microscopy, Raman scattering, IR-Fourier and X-Ray phase analysis, and spectral ellipsometry. According to the results of nano techniques, the relationship between amplitude and phase-frequency components of ellipsometric measurements and phase structure transformations has been established. The structural transition in the vicinity of 573 K, has been found. [ABSTRACT FROM AUTHOR]

The effect of a constant magnetic field (0.17 T) on microhardness, kinetics of photoconductivity decline and electro conductivity in silicon crystals is studied. The nature of changes of micromechanical and electrophysical characteristics in samples is investigated as a function of time elapsed after magnetic treatment. The results obtained are discussed in terms of magnetic field stimulated processes occurring in a subsystem of structural defects. [ABSTRACT FROM AUTHOR]

Bulk samples of cadmium arsenide and manganese arsenide alloys were synthesized by crystallization from double-component melt. According to data of differential-thermal and X-ray phase analysis, the nature of the interaction between Cd3As2 and MnAs is eutectic; the melting temperature of eutectic is 855 K. The samples were ferromagnetic with Courier temperature of 320 K. By vacuum-thermal evaporation from the alloy of the composite, films Cd3As2 + MnAs have been obtained. The distribution of the elements in them was uniform and the composition corresponded to the initial composition. The films consisted from nanocrystallites with a size of 20 to 50 nm. [ABSTRACT FROM AUTHOR]

The features and patterns of self-organization processes in the diffusion-limited conditions (method of drops) of carbon-containing compounds and carbon nanotubes have been studied. The results of the research influence of the substrate temperature and solvent on the formation of nanoscale fractal structures in sediments of colloidal solutions are provided. [ABSTRACT FROM AUTHOR]

The investigation results of nanoscale phenomena and structural changes due to shock localized impacts at electric discharges on thin metal films from copper and chrome are given. Mechanisms of shapeformation of concentric circles within discharge area and ordered nanoparticle aggregates on film surfaces are provided. [ABSTRACT FROM AUTHOR]

Characteristic sizes of sodium octanoate micelles have been determined (by nucleus radius) with the use of small angle X-ray scattering technique at various molar concentrations, which are for a spherical shape 1 and nonspherical 1.2 nm, respectively. The value of the critical concentration for micelle formation (CMC2) has been also found equal to 0.7 M. [ABSTRACT FROM AUTHOR]

The influences of carbon additive on the structure and phase composition of the positive electrode material as well as technical and operational characteristics of starter lead-acid batteries have been studied. The mechanism of interaction of carbon additives with lead powder is proposed. It is established that the presence of carbon in the positive electrode material increases the lifetime of lead-acid starter batteries, as confirmed by tests. [ABSTRACT FROM AUTHOR]

By small angle X-ray scattering (SAXS) and atomic force microscopy characteristic sizes are determined, structural features of thin iron films deposited by magnetron evaporation onto substrates from pyroceramics are established. It is shown that morphologically the film is characterized by disorder. It is formed from columnar nano crystallites that are oriented either perpendicular to the substrate or situated in its plane, which dictates polydispersity of those coatings. It is shown that SAXS may be thought of as nondestructive technique for analyzing structure and composition and conducting quality control of magnetron films. [ABSTRACT FROM AUTHOR]

By small-angle X-ray scattering and atomic force microscopy shows the features of the structure of thin films of Si3N4 and SiC, deposited by magnetron sputtering on glass substrates. [ABSTRACT FROM AUTHOR]

By using the advanced nano-approach processes and phenomena in self-organizing colloidal systems are studied. The conditions of appearance of self-organized phenomena are determined and also ranges of operation of diffusion, capillary, and fractalization mechanisms are found. [ABSTRACT FROM AUTHOR]

Qualitative mechanism in line with experimental data on visualization of the domain structure and fine structure of the domain wall in weak ferromagnets has been proposed. The mechanism is based on the phenomenological consideration of Faraday rotation, optical absorption, and atom polarization in response to the radiation exciting Raman scattering. Qualitative agreement of estimates on the scattered radiation intensity in oppositely- magnetized domains with experimental results is good, which made it possible to attack problems of visualization of magnetic entities with nanoscale resolution. [ABSTRACT FROM AUTHOR]

Langmuir films from stabilized barium titanate nanoparticles have been produced. The processes of polarization and polarization reversal of ferroelectric coatings obtained were studied. The inverse piezoelectric effect has been recorded and its quantitative characteristics have been determined. [ABSTRACT FROM AUTHOR]

The method of optical spectroscopy determined photoluminescence properties of zirconia nanoparticles produced by laser ablation. The effect of annealing of nanoparticles in the range from 400 to 1000 °C on their luminescence is investigated. It is shown that the emission of the luminescence make it possible to conclude about the type of defects in the structure of nanoparticles and their dynamics during annealing. A qualitative explanation of the detected patterns is provided. [ABSTRACT FROM AUTHOR]

The nanopowders of the transition metal ZrO2 and HfO2 oxides were obtained by the hydrothermal autoclave synthesis. The nanoparticles possess a rounded shape and a size range of 40 to 80 nm (ZrO2), of 10 to 40 nm (HfO2). X-ray diffraction analysis and electron microscopy show that the structure of the nanoparticles is monoclinic. [ABSTRACT FROM AUTHOR]

The aqueous dispersion of silver nanoparticles have been obtained and studied by physicochemical methods. Maximum of size nanoparticles distribution in the aqueous dispersion determined by the small angle X-ray scattering technique was 2.5 nm. The composition on the basis of those nanoparticles can be used to create new nanomaterials, in particular for the modification of talc silver nanoparticles. The existence of nanoparticles at the talс surface is corroborated by the data of energy dispersive spectra and by X-ray diffraction spectra. [ABSTRACT FROM AUTHOR]