Thermal processes at growh of non-activated scintillational materials

The object of research is the directed crystallization partly of semitransparent materials from melt. The subject of research is mathematical models of radiation-conductive and radiation-convective heat exchange. Mathematical models and techniques of numeral solution of tasks of ra-diation-convective heat exchange are worked out taking into account influence of impurities in melt on an asorptance and selectivity of optical properties of semitransparent crystal and melt.

The gas discharge decreasing in the great and small energetic and on Ukraine compression stations on the basis of introductions of closed gas turbine and thermodynamically forced two-fuels monic technology

The new enthalpy-entropy method of the thermodynamic analysis of gas turbine cycles and combined on their basis energetic installations is developed. Methods of the thermodynamic forcing, at the first, of basic gas turbine installations by connection to them of closed gas turbines, which produce additional electric energy by utilization of the gas turbine exhaust gases heat potential, and, at the second, one-fuel monic gas-steam installations with using of the steam extended expansion turbines is proposed.

Formation of stable nanoscaled magnetic FePt films for high-density magnetic recording and information storage

It is developed new approach for diffusion formation of stable nanoscaled magnetic-hard FePt films with chemically ordered L10(FePt)FCT phase at using additional layers of alloying elements (Ag, Au, Cu) with low surface energy. The energy of interface between layers was applied as additional superior-driving force for acceleration of thermally activated processes of chemical ordering FePt film and decreasing of temperature (~ 100oC) of phase transformation of chemically disordered magnetic-soft А1(FePt)FCC to chemically ordered magnetic-hard L10(FePt)FCT phase with superstructure.

Investigation of statistical characteristics of partially coherent laser beams for application in optical communication systems

Electro-magnetic waves propagation in atmosphere is of great theoretical and practical interest because using laser radiation for information transmission through the earth's atmosphere has many obvious advantages over traditional communication methods. However, fluctuations of the refractive index in the atmosphere, caused by turbulence, lead to the optical field fragmentation in the detecting area and to the beam wondering in regards to the initial direction.

Modeling the economic development strategy of enterprises in a socially oriented economy Ukraine

The current concept of enterprise development strategy under which the company is directly linked with its social and economic value, which is determined, along with technical and economic indicators - for a system of values, competencies and resources, effective management which causes the growth of the market value of the company. Determined system of qualitative and quantitative assessment of the corporate social responsibility of the enterprise.

Heat transfer physical process at miniaturization an evaporation-condensing thermal stabilization systems

New complex mathematical model of heat transfer processes in conditions of evaporation-condensation systems (miniature heat pipes, thermosyphons and pulsating heat pipes) inner space decreasing was developed. Criterial relation for evaluation of miniature heat pipes heat transfer ability was obtained as a result of differential equations system and conditions of uniqueness analysis.

Spectral characteristics of magnetically ordered low-dimensional nano- and micro-objects in the exchange mode

The theory was developed of propagation of spin waves in two-sublattice antiferromagnet with uniaxial magnetic anisotropy and ferromagnetic nano-shaped spherical nanoshell, nanoshell of an ellipsoid of rotation form ("nanorise"), cylindrical nanotubes of circular (circular cylinder) and elliptical (elliptical cylinder) section and for arbitrary ferromagnetic nanosystems with transmitting symmetry.

The size effects in the structures based on silicon carbide

Conditions for creation of light emitting diodes working in electrical breakdown regime have been determined. The floatable technology have been used. Light emitting diodes obtained is possible to use as standards of power and spectral composition of radiation, and although for creation of sources of short light impulses. Constructions of these devices, laboratorial technology of their fabrication, elements of metrological support have been worked out.
Emitters on SiC-basis operating in the electrical breakdown regime have the following superior characteristics:

Development of theoretical basics, methods and tools for design of modern high speed computer systems in Grid and Cloud systems

A new architectural concept of parallel computing in GRID systems and cloud environment is proposed, which uses FPGA as a high-performance heterogeneous computing resource. FPGA is used as heterogeneous programmable operating unit for processing data streams, allowing for achievement of optimized performance-related energy consumption. The concept simplifies programming the computational problems for these systems.

Dispersion-stabilized hydrocarbon oligomers and their potential for nanospintronics

Spectral, thermal and electronic properties of a new class of hydrocarbon-based materials diamondoid oligomers was investigated. The methods for the selective functionalization of lower and higher diamondoids were developed. Methods of association lower diamondoids in lower oligomers have been developed. X-ray diffraction and thermogravimetric spectra of lower diamondoid oligomers were made. We propose a model that adequately accounts the effects of dispersion interactions in diamondoid oligomers for their physicochemical characteristics.

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