PHYSICA CONDITINS OF THE ‘LIGHT’ CORE FORMATION AND THERMONUCLEAR HEAT SOURCE DEEP INSIDE THE EARTH

Purpose. Experimental research into the physical model of the Earth’s core formation in the center of gas‑dust spiral vortex and numerical assessment of the physical conditions associated with the development of thermonuclear reactions in the Earth’s core. Methodology. Analysis of the main points of conventional conceptions, their principal merits and drawbacks which delineate their potential possibilities. Experimental studies implementing shock‑wave treatment of porous materials in cylindrical containers. Numerical assessment of the physical conditions that initiate thermonuclear reactions in the Earth’s core. Findings. It is extremely important to choose the model of the Earth formation with originally “light” core for several reasons. First, it provides a physically grounded mechanism of the thermonuclear heat source formation;second, the process of the Earth transition to equilibrium state inevitably creates conditions for mechanical, physical and chemical activity of elements in geospheres. Numerical assessment was performed to estimate the main conditions which are necessary for thermonuclear heating of the Earth’s central bulk – to determine the deuterium nuclei concentration and the respective temperatures. Originality. The authors suggested a model describing formation of the initially “light” core of the Earth. Experiments allowed studying some physical peculiarities of spiral vortices initiation and development. Regularities of change in plasma parameters, core temperature and thermonuclear energy release have been established in reference to the Earth’s age. Practical value. The obtained results will be useful for studying such important planetary geological phenomena as matter differentiation and formation of spheres inside the planet, as well as heat flow distribution in its bulk

ON FORMATION OF ELECTRICALLY CONDUCTIVE PHASES UNDER ELECTROTHERMAL ACTIVATION OF FERRUGINOUS CARBONATES

Purpose. Study of the formation of an electrically conductive phase in carbonates using siderite as an example and determination of the temperature dependence of its formation and silicon content during simultaneous heating and the action of a weak electric field. Methodology. Analysis and generalization of the results of experimental studies. Physicochemical analytical studies have been performed using electron and optical microscopy, petrographic and X-ray phase analysis, thermogravimetric analysis and differential scanning calorimetry, and gas chromatography. Phase equilibria in the “iron oxides – carbon – carbon oxides” system have been evaluated using data on the standard change in the Gibbs energy Evaluation. Findings. Formation of electrically conductive phases in siderite has been studied. The dependence of new phase formation on heating and the magnitude of the electric field strength have been determined. The regularities of the change in threshold temperatures of phase transitions in samples of siderite and calcite containing silicon impurities have been established. Originality. Due to the thermally stimulated increase in the concentration of mobile charge carriers in intergranular space, the electric field of point charges takes the prominent part in the formation of the end product of chemical reactions. The additional effect of electric current on the increasing destabilization of chemical bonds between surface atoms leads to the formation and transport of ions, to a decrease in the energy barrier of nuclei formation of the electrically conductive phase near the active centres. The abrupt increase in electrical conductivity is due to the spontaneous formation of the nuclei of a new phase and the transition of ionic conductivity to a mixed one or an electronic one primarily. A composite semiconductor is formed as a result of electrothermal activation of siderite. This semiconductor consists of a matrix-semiconductor representing the initial mineral and is penetrated by parallel-oriented highconductivity threads. Practical value. Experimental results show that such processes occurring in rock are quite real under the conditions of the earth’s crust, and the physical values of thermodynamic quantities (factors of metamorphism) are sometimes overestimated significantly in the interpretation of various geological events

ELECTRICAL ChARGES AS CATALySTS OF ChEMICAL REACTIONS ON A SOLID SuRFACE

Purpose. To determine the change dependency of the potential energy of the chemical bond of a diatomic molecule on the value of the point charge and its distance to the bond using quantum mechanical calculation. Methodology. Numerical simulation of a quantum mechanical system consisting of a point charge and a diatomic molecule interacting with each other. Findings. The quantum-mechanical problem of the effect of an external Coulomb center on the chemical bond of diatomic molecules is solved. Originality. A quantum mechanical model of a physical system consisting of three interacting Coulomb centers (there is a chemical bond between two of them) is developed. The model makes it possible to understand the dynamics of the interaction of a molecule with an ion, the charge of which can be characterized by either integers or fractional numbers. The change in the energy of the chemical bond in the ion field depending on the distance to the bond and the magnitude of the charge is established. Practical value. The developed technique for calculating the energy of a chemical bond as a function of the magnitude of the electric charge was used in the development of the method for growing single crystals of metastable diamond, in calculating the limits of the chemical bond stability in metal azides, in developing the way of additional harmful gases formation during rock blasting and in calculating the stability of nanoscale hydrocarbon chains in coal, and others. The method can be used to decide on the catalyst and control the catalytic reactions

THE MACROKINETICS PARAMETERS OF THE HYDROCARBONS COMBUSTION IN THE NUMERICAL CALCULATION OF ACCIDENTAL EXPLOSIONS IN MINES

Purpose. Obtaining effective parameters of the macrokinetics of combustion of hydrocarbons in the deflagration and detonation regime for the numerical calculation of emergency explosions in mine workings. Methodology. Mathematical modeling, numerical experiment, kinetics analysis of explosive combustion reaction, analysis and synthesis. Findings. The paper analyzes the parameters of the kinetic equation against experimental data. Obtaining such data in a physical experiment for explosive chemical reactions meets serious difficulties. This is due to the size of the reaction zone not exceeding fractions of a millimeter, the lack of time resolution of experimental techniques and other factors leading to errors in direct measurements and the emergence of multiple solutions. This possibility contributes to obtaining a simultaneous numerical solution of the equations of gas dynamics and chemical kinetics. In the numerical experiment, a direct relationship between the macrokinetic characteristics of the chemical reaction and the parameters of the discontinuous flow of the reacting gas stream is established: velocity, pressure in the front and behind the front of the detonation and deflagration wave. Based on this, Arrhenius characteristics of the reaction – preexponential and effective activation energy for the hydrocarbons under consideration are obtained. Originality. Macrokinetic parameters are established for simulating one-stage ignition and burning of the most probable hydrocarbons of the mine atmosphere in the deflagration and detonation regime. Modeling of explosive combustion of premixed hydrocarbons in stoichiometric concentrations is performed. It is shown that the values of the effective activation energy in explosive combustion reactions are of less importance in contrast to steady-state combustion reactions because of the effect of the gas-dynamical effects of the shock wave on the reaction rate. The Arrhenius characteristics of the reaction – the pre-exponential and the effective activation energy – have been agreed upon, according to the gas dynamic and kinetic parameters of the course of the explosive combustion reaction. Practical value. The obtained parameters of the macrokinetics of the explosive combustion reaction make it possible to apply simple kinetic mechanisms in practical calculations of the processes of deflagration and detonation combustion, and to predict the parameters of emergency explosions in conditions of mine workings with sufficient accuracy. This also makes it possible to solve the problem of accounting for the presence of heavy hydrocarbons in themine atmosphere as products of coal pyrolysis in underground fires as factors of increasing the risk of emergency explosions

MECHANISM OF THICK METAL WALLS PENETRATION BY HIGH-SPEED MICROPARTICLES

Purpose. Analysis and estimation of physical parameters which create conditions for microparticles penetration into metal microstructure to abnormally big depth. Methodology. Quantum mechanical three­site model has been used for studying the regularities of electron motion in the field of two Coulomb centres and numerical solution for the problem of the effect of external electrical charge on stability of the chemical bond. Solution was found for the equation of heat conductivity for estimating the temperature of microparticles heating under compression and acceleration by explosively driven accelerator. Stokes’s law was used for estimating viscosity of hypothetical medium which can be penetrated by microparticle at a great speed and to a great depth. The research was done with the help of X­ray microanalysis, X­ray crystallography, micrographic investigation, mass­spectrometry and electronic spectroscopy. Findings. Solution of the quantum mechanical model testifies that electric charges serve as catalysts responsible for the significant reduction of the energy barrier of chemical reactions. To ensure super deep penetration, it is necessary to achieve acceleration of a great number of microparticles in a special explosively driven accelerator. Heating, intensive stirring and friction result in electrification of the surface of the particles, which is known as triboelectric effect. The hypothesis about physical and chemical mechanism of particles penetration into metals resulting from high­speed impact has been put forward. Originality. The research has established relationship between the sizes of microparticles accelerated by explosion and the density of electric charges on their surfaces, as well as the depth of their penetration into the metal barrier. By experimental research, it was proven that maximum depth of microparticles penetration is directly proportional to the maximum density of surface charges for the particles of the 50…80 µm size. It is assumed that particles penetration into metals to greater depths is conditioned by the reduction of the barrier material viscosity in the zone of particle­barrier contact due to quantum mechanical effects in the solid­state plasma. Practical value. The value of the work includes creating a new generation of metal composites as well as new prospective technologies of reactive materials utilization

Calculation of the close packing of fine aggregate on the basis of screening for fine grained concrete

The paper considers the calculation of the maximum packing density of fine aggregate. The selection of the granulometric composition of the aggregate is given. The bulk densities and packing densities of standard screening fractions were determined. The content of each fraction in the mixture and the packing density of the aggregate mixture are calculated by the introduction of a subsequent finer fraction. Topological calculation of sandstone screening was performed. The results of sieving of sandstone screening are presented. The high-density grain composition of aggregate for fine-grained concrete is obtained. The compositions of concrete mixtures have been designed. The volume ratio of aggregate and cement paste in the concrete mix, the average mass size of the aggregate grains in the mixture, the volume fractions of cement and water in the concrete mixture are determined. The physicomechanical characteristics of fine-grained concrete of various compositions with a high density aggregate are shown. Results of testing the control samples for compressive strength are given. The density of the obtained samples was determined. Conclusions are drawn on the work.Keywords: Fine-grained concrete, fine aggregate, granulometry, screenings, sandstone, highdensity aggregat

Profiled detonation waves in the technologies of explosion treatment of metals

A short review is represented concerning physicotechnical features of current technologies, plane-wave, converging cylindrical and spherical detonation waves used in physics and chemistry of high energy densities, physics of metals, materials science, machine building, and mining and metallurgical industry. The main drawbacks of existing technologies are shown, and attention is focused on the technical nature of the reasons limiting their application. Attention is paid to solving the problem of simultaneous initiation of detonation of the entire surface layer of a light-sensitive explosive, regardless of the shape of the surface. A physical and mathematical methodology for estimating shock-wave parameters of an explosive during initiation of detonation in it by explosion of the initiation layer of the charge of a lightsensitive explosive composite is proposed. Prospects of practical application of detonation (shock) waves of the specified profile formed by laser ignition of the surface of a light-sensitive explosive composite are discussed. Physicochemical potential of the system of laser initiation of detonation makes it possible to form any wave profiles and get pulses of the intensity from 0.1 to 1.0 kPa⋅s on the surfaces being more than 1 m2. Precision and safe system of laser initiation can be used during any types of blasting operations including the ones that cannot be implemented principally, while applying standard systems for initiating explosives and means of explosion

Изучение морфологических и биохимических показателей растений <i>Amaranthus tricolor</i> L. сорта Валентина

Morphometric and biochemical indices of the red-colored Amaranthus tricolor L. Valentina variety were studied, the content of the reduced form of vitamin C, the amaranthine pigment in roots, leaves, stems and inflorescences was determined. Studies have shown the presence of a high concentration of vitamin C in the leaves of amaranth both in the open ground (195 mg%) and in the film greenhouse (176 mg%). In the leaves of amaranth of different varieties of the species Amaranthus tricolor, a large amount accumulates a secondary compound - an antioxidant - amaranthine. The red-violet color of the inflorescences is due to the presence in the vegetative organs of the plant of the red-violet pigment of amaranthine. It is important to note that the amaranth Valentine variety have found substances with antioxidant activity: ascorbic acid, selenium, carotenoids, methionine. In the largest amount, amaranthine is found in the inflorescences (2.18 mg/g) and leaves (1.41 mg/g). Its predecessors are D-glucose and L-tyrosine - photosynthetic metabolites, which are used in growth processes and in the biosynthesis of amaranthine In red-colored plants of the genus Amaranthus, betacianin-amaranthine is 5-O-glucuronidoglucoside betanidine. Leaves with a high content of red-violet pigment amaranthine used in the production of food additives-dyes Amvita and Amphicra, used in the food concentrates industry. These additives, due to their antioxidant properties, enhance immunity and have immunomodulatory activity. Extraction of amaranth leaves in H2O revealed high rates of antioxidant activity (CCA from 1.81 mg EQ GK/g). The low gluten content makes amaranth an extremely valuable and useful for functional food.Изучали морфометрические и биохимические показатели красноокрашенного растения Amaranthus tricolor L. сорта Валентина, проведено определение содержания восстановленной формы витамина С, пигмента амарантина в корнях, листьях, стеблях и соцветиях. Исследования показали наличие высокой концентрации витамина С в листьях амаранта как в открытом грунте (195 мг %), так и в пленочной теплице (176 мг %). В листьях амаранта разных сортов вида Amaranthus tricolor в большом количестве накапливается вторичное соединение - антиоксидант - амарантин. Красно-фиолетовая окраска листьев обусловлена наличием в вегетативных органах растения красно-фиолетового пигмента - амарантина. Важно отметить, что у сорта амаранта сорта обнаружены вещества с антиоксидантной активностью: аскорбиновая кислота, селен, каратиноиды, метионин. В наибольшем количестве амарантин находится в соцветиях (2,18 мг/г) и листьях (1,41 мг/г). Его предшественниками являются D-глюкоза и L-тирозин - фотосинтетические метаболиты, которые используются в ростовых процессах и в биосинтезе амарантина. В красноокрашенных растениях рода Amaranthus бетацианин - амарантин представляет собой 5-О-глюкуронидоглюкозид бетанидина. Листья с повышенным содержанием красно-фиолетового пигмента амарантина используют при производстве пищевых добавок-красителей Амвита и Амфикра, применяемых в пищеконцентратной промышленности. Эти добавки благодаря антиокислительным свойствам способствуют повышению иммунитета и обладают иммуномодулирующей активностью. Экстракция листьев амаранта в H2O выявила высокие показатели антиоксидантной активности (ССА от 1,81 мг экв ГК/г). Низкое содержание глютена делает амарант чрезвычайно ценным и полезным продуктом для функционального питания