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Information × Registration Number 0217U000831, 0114U002432 , R & D reports Title Theoretical and experimental studies of physical and chemical processes that form the basis of phase-chemical and atomic spectrometric methods of analysis, in order to develop methods of analysis of new types of alloys, composites and nanomaterials popup.stage_title Head Dubok Vitaly Andreevich, Registration Date 10-03-2017 Organization Frantzevich Insitute for Materials Science Problems of the Ukranian National Academy of Sciences popup.description2 The object of study was the chemical and physico-chemical processes in the application of chemical, physico-chemical and atomic spectrometric methods of analysis of the elemental composition of inorganic materials (mass spectrometry with glow discharge, emission spectrometry with spark excitation of spectrum) and the kinetics of fast spreading of the melt drops. The purpose of the work was the creation of methods of emission spectral and mass spectrometric analysis of high purity sapphire; analysis of the kinetics of reactions in the framework of the transition state theory; development of methods of determining the composition of powders and phases in the Al-B-C; the development of graphene synthesis techniques boron nitride, as well as methods of selective determination of carbon nanoforms a mixture thereof. Research methods - mathematical modeling and experimental study of a spark plasma parameters in the air with a stainless steel electrode; Mathematical modeling and experimental investigation of the mass spectra on the device with a high resolution VG9000 in cathode sputtering of single crystals of sapphire; calculations of the kinetics of fast spreading metal droplets on the surface of metals and ceramic materials analysis of the mechanism of chemical reactions borate acid and urea to form BN; calculation communication between graphene particle diameter of boron nitride and the amount of free connections on the perimeter of macromolecules, selective oxidation of carbon materials with coulometric determination of CO2. For the first time set a quantitative connection between the discharge power, the erosion rate of multi-electrodes and pressure parameters and the composition of the plasma spark discharge and the intensity of the spectral lines of atoms, singly and doubly charged ions. Analyzed the mass spectrum of the plasma glow discharge is created atlas of molecular interferences with sapphire analysis found the relative sensitivity coefficients of isotopes. It was shown that the kinetics of fast spreading of droplets can be described using the refined theory of absolute reaction rates. The proposed chemical model of formation of nano-sized particles of graphene-BN powders Borat-urea origin. The mechanism of formation of two-dimensional hexagonal lattice of graphene and graphene-BN with the branched chain reactions with free radical mechanism. The role of precursor polymerization reactions by free-radical pairs with the formation of planar BN particles. The developed methodology for determining the elemental composition of aluminum borides and carbon powders as well as methods of direct determination of carbon nanoforms present as the free carbon impurities in the industrial boron carbide powders. Developed by selective chemical methods for determination of cross-laminated carbon fibers nanocarbon materials by oxidation in a stream of O2 and CO2 coulometric measurement set temperature rapid oxidation phase nanoforms carbon number, including a cross-layered graphene industrial carbon and graphite nanofibers cellulose acetate fabric pyrolytic origin. The proposed methods provide the theoretical foundation of atomic spectrometric techniques of elemental analysis of inorganic materials, increase their accuracy and rapidity, significantly extend the capabilities of existing instrumental methods of certification of carbon nanomaterials, provide the basis for improved methods for the synthesis and purification of ceramic powders based on aluminum dodecaboride. Product Description popup.authors Гарбуз В.В. Дубок В.А. Кузьменко Л.М. Курочкін В.Д. Петрова В.А. Романенко О.М. Суворова Л.С. popup.nrat_date 2020-04-02 Close