It is shown that the investigation of isotope effects in condensed matter is related to the farther increase in the efficiency of separation methods, and the main purpose of this work consists in determination of the processes and materials the qualitative and quantitative characteristics of which directly depend on the isotope content of the matter. Determination of appropriateness and mechanisms of the influence of the isotope effects on the properties of the medium opens up fresh opportunities for changing from the technology of isotope substances, pure in the sense of admixtures, to the technology of pure isotope substances. It was established that purposeful utilization of isotope effects in various physical phenomena and processes substantially extends the sphere of utilization and production of stable and nonstable isotopes.

Such an approach to the isotope problem has also led us to promising branches of physics and technology – physics and isotope-stimulated phenomena and isotope material science. This relatively new field of solid state physics and molecular physics includes the study of isotope effects of various media and elaboration of the materials of the specified isotope composition.

Keywords: material, amorphism, crystallinity, isotope, effect, growth, bonds.

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Basing on the theory of generalized δ-like functions, a theory of the symmetric dipole formed of thin rectangular metallic plates has been developed. An integral equation for the surface current density was derived and its rigorous solution at h/λ >> 1 (h - the dipole length, λ - the wavelength) was constructed. The analytical expression for the dipole directivity characteristic and input resistance was also derived.

Keywords: symmetric dipole, surface current density, directivity characteristic, theory.

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3
APPROXIMATE METHOD FOR SELECTION OF THE RIGIDITY OF SHELL STIFFENING SYSTEMS IN ACCORDANCE WITH THE SPECIFIED VALUE OF THE CONSTRUCTION BASE FREQUENCY

A calculation model for determining the normal response of stiffening systems installed in a plain shell for increasing its rigidity is proposed. The specified value of the stiffening system base frequency was assumed as a universal parameter of rigidity. The problem solution, which is based on Hamilton's principle with application of false loads corresponding to the forms of base frequencies, consists in determination of the mentioned response by the difference between the base frequencies of the stiffened and plain shells.

Keywords: shell, stiffening system, rigidity section, approximate method.

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The method of approximation of Buckingham's equation, based on application of the irrational function with variable coefficients, is considered. The advantage of the method in comparison with the existing ones is its sharply increased accuracy.

Keywords: Buckingham's equation, approximation, irrational function.

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There is presented the asymptotic approximation to the solutions of the problems of the moment theory of spherical shells, in which all the functions of the stressed-strained state are expressed by elementary functions and any boundary conditions can be realized.

Keywords: spherical shell, rotation, stressed-strained state.

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A new-type prestressed space construction is considered. Calculation of the close-looped flexible thread as a main stage in determining the construction parameters is proposed. The considered calculation has an advantage in comparison with the available methods.

Keywords: space construction, flexible thread, closed loop, calculation.

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There is formalized functioning of an asynchronous accumulating summator and are given initial conditions for its synthesis. The characteristic equation of the accumulating summator was obtained using the Boolean differential. There are proposed methods of the synthesis of the accumulating summator on the basis of a dictionary-operational method of synthesis of accumulating digital schemes.

Keywords: accumulating summator, synthesis, methods

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The problems of formalization of the synthesis of difference elements for accumulating circuits are considered. There have been derived characteristic equations of the difference elements. The equations allow one to formalize completely the process of synthesis of the accumulating circuits based on the difference elements.

Keywords: accumulating circuits, difference elements, synthesis.

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The work is devoted to mathematical simulation of sea waves in the coastal zone of Poti. The basic equations of the model and the numerical algorithm of its realization are considered.

Keywods: coastal waves, mathematical model, numerical algorithm, finite element.

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There are presented the results of theoretical and experimental determination of the coefficients of serviceability and reclamation of the components of motor unit Super 610, produced at Kutaisi Plant "Saktractor". The analysis has shown that some components (conical fraction, piston, etc.) of the motor unit need design improvements.

Keywords: motor unit, coefficients of serviceability and reclamation, analysis.

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The results of designing of a gas-turbine engine case for pulse dynamic load under severe conditions of an aircraft (n = 9.6) are presented. The forms and periods of natural oscillations of the gas-turbine engine case were determined.

Keywords: gas-turbine engine, case, pulse effects, method of finite elements, design, oscillation forms.

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With the help of self-propagating high-temperature synthesis (SHS), new composite ceramic materials both as powders and compacted materials (SHS-compacting technology) have been "designed". Technological schemes of their synthesis are presented. The advantages of the SHS process in comparison with other ceramic technologies are shown.

The synthesized consolidated materials have better (in comparison with monophase technical ceramics) physical and mechanical characteristics. The phase composition and structure of detonation coatings from the SHS-composite powders were investigated. In the optimum mode of detonation evaporation, the thickness of covering was 450-500 μm. The coating was multiphase. It is assumed that besides the basic phase components of initial SHS-powders: TiB₂; Al₂O₃; B₄C; in the covering matrix there are TiC and other complex compounds.

Keywords: composite ceramic materials, synthesis, process combustion, powder complexes, coatings.

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An original model of target forecast in expert estimation of the pollution level of water objects (rivers, lakes, reservoirs etc.) is proposed. In this model, there is carried out the target forecast in the expert estimation of possible consequences of the effects of hazardous substances onto the human health. As a criterion, minimization of the adverse impact on the human health is assumed.

With the help of this model, it is possible to reveal hazardous areas of an "emergency ecological situation" and an "ecological disaster" and to outline the priority of chemical (toxic) pollutants adversely affecting the human health.

Keywords: water object, pollution, expert estimation, forecast.

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There was carried out computerized computation using the three-dimensional problem solution concerning the wave generation process in a schematic reservoir due to a landslide masses "inflow" from a bank slope. Basing on the obtained data, the graphs were constructed to evaluate the influence of the basic parameters of the process on the maximum wave magnitude at the dam site.

Keywords: reservoir, dam, landslide, water level, design parameters.

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A simple analytical dependence is presented to predict rapidly the possible maximum amplitude of the waves at a dam site caused by a landslide in a narrow reservoir. This dependence is obtained on the basis of computing data analysis using the corresponding plane hydrodynamic problem solution.

Keywords: dam, reservoir, wave amplitude, landslide.

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The problems of technical maintenance of water supply and control of water consumption in the water economy and melioration systems of Georgia and the ways of their solution are presented. The problem of designing the system for monitoring water consumption in open water reservoirs and irrigation canals is stated. The monitoring system should be equipped with automatic level and flow meters, devices for information transmission, reception and processing, etc. Basic specifications and operational requirements for such a system are outlined.

Keywords: water economy, melioration system, water consumption, monitoring.

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There are considered the methods for eliminating the inclinations of buildings exeeding the norm, including the method developed by Interbiotech Ltd, Rostov-on-Don, Russia. This method involves application of new-type flat jacks, examination of the building and usage of an automatic control system controlling the process of building lifting. The data on the most typical objects from the experience of Interbiotech Ltd are presented. Generalization of the accumulated data has allowed to work out the basic requirements to building lifting and to state the problems for numerical modeling of the levelling process.

Keywords: building lifting, calculation design, adjustable foundation.

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A technology of making monolithic the joints of buildings without using formwork and with mechanized filling of joint cavities with concrete or mortar is considered. There is presented the established dependence of the mortar strength on the cement - water (C/W) ratio and the corresponding equations, including the equations which account for cement brands and cement amount, and for granulometric composition of sand. It is shown that preliminary removal of free water leads to an increase in the C/W ratio and, consequently, to improvement of the mortar strength. Long-standing experience shows the advantages of the proposed technology of making monolithic the joints of industrial buildings.

Keywords: construction, industrial buildings, joints, waterproofness.

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Functional bacteria and archaea communities of an anaerobic thermophylic batch biodigester fed with cattle manure were analyzed by Polymerase Chain Reaction – Single Strand Conformation Polymorphism (PCR-SSCP) and sequencing of 16S rDNA genes. PCR-SSCP technique enabled rapid and overall detection of bacteria and archaea populations. The evolution of profiles was studied. Twenty-six bacteria and twenty-six archaea OTUs (operational Taxonomic Units) were detected by 16S rDNA sequencing and identical clones were selected in groups.

35% of the analyzed bacteria clones are phylogenetically close to the 16 S rDNA sequence of the (gram+) uncultured bacterium. 10% of the bacteria clones are phylogenetically close to the same (gram+) uncultured bacterium. 30% of the analyzed bacteria clones are phylogenetically close to Clostridium sp. FCB90-3, Clostridium hydroxybenzoicum and Eubacterium limosum. The rest 25% bacteria clones are phylogenetically close to 16S rDNA of Pseudomonas, sulfide-oxidizing bacterium N9-1, Zoogloea sp. and Uncultured eubacterium WJGRT-149.

50% of the analyzed archaea clones are phylogenetically close to 16 S rDNA of Methanoculleus thermophilicus, 25% of the analyzed archaea clones are phylogenetically close to Methanosarcina thermophila. The rest 25% sequenced archaea clones are phylogenetically close to Uncultured archaeon.

Keywords: anaerobic digestion, 16S rDNA, SSCP.

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Orientation of structural components of ionic fumarate-containing compounds was established. Peculiarities of their packaging were also determined. The investigation was carried out with the help of X-ray structure analysis.

Keywords: X-ray structure analysis, ethylenediammonium, fumarate.

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The results of the investigation of the non-empirical (ab-initio) equilibrium structure of hexamethylene tetramine (HMTA) are presented. Local minimums at the potential energy surface were determined using the Hartree-Fox method. There were calculated the equilibrium geometrical structure, electron density and oscillation frequencies of HMTA. It is shown that all the equilibrium structures are of T_d-symmetry. Apparently, reduction of the HMTA molecular structure occurs under the influence of solvents.

Keywords: hexamethylene tetramine (urotropine), structure, special features.

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The reaction of hydrosilylation of the a , w - trimethylsiloxymethylhydridesiloxane oligomer (n» 35) to trimethylacryloxysilane at 1:35 ratio of initial compounds, in the presence of a catalyst - platinum on carbon (0.1% weight) was investigated and comb-type methylsiloxane oligomers containing trimethylpropionyloxysilane groups in the side chain were obtained. The hydrosilylation reaction order, rate constants and activation energy were calculated. By NMR spectra data it was shown that the reaction proceeds by the Farmer rule. The synthesized oligomers were studied by differential scanning calorimetry and wide-angle roentgenograpy.

Keywords: hydrosilylation, methylhydridesiloxane, trimethylacryloxysilane, activation energy.

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The reaction of hydride addition of a , w - bis(trimethylsiloxy)methylhydridesiloxanes with acrylic esters, at the ratio of initial compounds 1:35, in the presence of platinum chlorohydric acid has been investigated. Comb-type polyorganosiloxanes with a propionic acid ester fragment in the side chain, completely dissoluble in organic solvents, were synthesized. The hydrosilylation reaction order, activation energy and rate constants were found. The synthesized oligomers were characterized by IR, NMR spectra, gel permeation chromatography, differential scanning calorimetry and wide - angle roentgenography.

Keywords: organosiloxanes, hydride addition, acrylic esters.

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Soluble polymers ~5000 were obtained by trimethylsilylation of natural silicates (philipsite, natrolite, lomontite, askangel) at relatively high temperature of ~100⁰C. Physical and chemical properties of the obtained polymers and oligomers were studied by the methods of thermogravimetric, diffractometric and mass-spectral analysis. It was proved that insoluble polymer obtained from askangel is characterized by high thermostability (loss of mass 41.7%) in difference to the soluble polymers obtained from the other silicates.

Keywords: trimethylsilylation, natural silicates, silicon-organic polymer.

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The dependence of E_1/2 and the limiting current of reduction of the Fe³⁺ complexes with TEA on the solution pH has been studied. Fe³⁺ coordinates two particles of a ligand in a weak-acid medium. The reduction of the complex leads to formation of the complexes with one ligand particle. In a base medium, the complexes with Fe³⁺ are much more stable as compared with the Fe²⁺ complexes. Both Fe³⁺ and Fe²⁺ coordinate three molecules of TEA forming the complexes [Fe(TEA)₃]³⁺ and [Fe(TEA)₃]²⁺.

Keywords: polarography, triethanolamine (TEA), iron (III), complexes, ligand, stability.

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The behavior of rutin and quercetin in base solutions has been investigated polarographically. It is shown that both rutin and quercetin manifest clear polarographic waves. For correct interpretation of the polarographic measurements, rutin and quercetin adsorption on a mercury calomel electrode under similar conditions was studied.

Keywords: polarography, differential capacity, adsorption, rutin, quercetin.

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There was studied separation of the mixtures of n-paraffins and organic hydrocarbons C₆ at the capillary column with methyl silicone elastomer SE-30 as a stationary phase using gas carriers He, N₂ and CO₂. A device for application of two gases simultaneously is proposed. The device allows to separate complex mixtures of organic substances without temperature programming. It is shown that application of CO₂ as an eluent in capillary chromatography reduces the time of the complex mixtures analysis, reduces the asymmetry of chromatographic zones and increases the column efficiency.

Keywords: chromatography, capillary column, stationary phase, adsorptive properties.

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Brief information about the theoretical investigation of the process of transformation of citric acid into cis-aconitic acid and of cis-aconitic acid into isocitric acid by the methods of quantum chemistry (AM1) and algebraic chemistry (quasi-ANB-matrix method) is presented.

Keywords: citric acid, cis-aconitic acid, isocitric acid, AM1, quasi-ANB-matrix.

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Distribution of zirconium in the suspended matter and bottom sediments of Georgian surface waters was studied. It was established that the zirconium content approximates to the clark and decreases in the river flow direction. That fact may be explained by zirconium accumulation in the heavy fraction. The same reason is for enrichment of the bottom sediments by zirconium to compare with the suspended matter.

Keywords: zirconium, content, surface waters, suspended matter, sediments.

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A method of obtaining copper (I) chloride from copper-containing raw materials is described. The method was realized by oxidation of copper-containing solid wastes, in particular waste contact masses of production of organochlorsilanes. The copper-containing raw materials were partially oxidized at 400-600^єC to provide molar ratio Cu:O = 2:1, ant then treated by heated concentrated HCl. Copper chloride was precipitated by cooling the filtrate to room temperature or by evaporation.

Keywords: copper (I) chloride, copper-containing wastes, oxidation, muriatic acid.

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The results of the investigation of the effect of prostaglandins on the activity of RNA polymerase at modification of animals with benz(α)pyrene are presented. It is shown that prostaglandin Ф_2α in combination with benz(α)pyrene causes significant activation of RNA polymerase in isolated nuclei of rat's liver. That can be caused by formation of the complex of preinition of the ferment matrix. Such changes can result in formation of new molecules. These processes apparently can be affected by the changes in the prostaglandin biosynthesis process. Basing on the abovementioned, it can be concluded that prostaglandins participate in proliferation processes.

Keywords: proliferation, prostaglandins, RNA polymerase, benz(α)pyrene, effect, indometacin.

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It has been proved that the results of hypokinesia of minks are similar to hypokinesia of sables: the growth of the bones slows down, their weight and solidity increase, the IOM, % decreases and the gracility index decreases. In minks reared in cages, the progressive growth and development of the skeleton takes place in accordance with the morphogenesis of the animal. The dynamics of the anatomic indices and the indices of bone growth are similar to the same of sables. Under the conditions of free mobility, the growth of the skeleton is equable and proportionate to the age of the animals and to the stato-dynamic load of their locomotor apparatus. At the same time, under the conditions of limited mobility various parts of the skeleton grow asynchronously, and the osteoplastic process in general slows down.

Keywords: long bones, minks, age alterations.

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When foxes are kept in cages, the growth of theirs bones slows down, and the index of bones solidity increases. At the same time, wild foxes show higher index of gracility of the parts of their skeleton. This proves that the in natural biocenoses the macroarchitectonics of the long bones of the foxes change towards the development of more gracile anatomic constructions.

So, both in cages and in natural environment the skeletal system of the foxes grows and develops progressively. In natural environment the growth of the parts of the skeleton is proportionate to the age of the animals. At the same time, in cages the growth of the skeleton slows down which is proved by some degree of the age stability of macromorphological and osteometric indices.

Keywords: long bones, foxes, age alterations.

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By mathematical simulation, the influence of the dyeing conditions (temperature, module time etc.) on the changes in the intensity of the obtained colour of natural silk and polyamide treated with borax was studied. The optimum dyeing parameters for obtaining the colour of maximum intensity were determined: dyeing should be carried out at 80-85єC for 30-35 min; the fiber mass being equal to 40-50. To obtain the colour of the specified intensity, the dye expenditure can be reduced by 20-25%.

Keywords: silk, polyamide, dyeing, borax, modification.

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By IR spectroscopy, the possibility of formation of boron complexes with natural silk and polyamide fibers was investigated. The analysis of IR adsorption spectra of the fibers of natural silk and polyamide , both treated and untreated by borax and dyed, showed the adsorption bands, characteristic of boron complexes, and the changes, evidencing of the interaction with boron.

Keywords: silk, polyamide, boron complexes, IR spectroscopy.

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Red wines were produced from grapes Saperavi and Tavkveri using engogenic enzyme complexes. The wines were produced 6 days later the alcoholic fermentation conclusion. The wines have been estimated as more sophisticated, admissible by bitterness and astrigency, and pocessing better flavor and aroma in comparison with the wines produced by other methods.

The organoleptic estimation confirmed that these wines comply with the requirements to the parameters of wine components and pigments. Basing on the obtained results, it was concluded that the endogenous enzyme complexes can be recommended for application in order to improve the wine aroma and flavor.

Keywords: red wines, endogenous enzymes, pomace contact time, must, flavor.

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Some chemical and terminological historical aspects related to Georgian mineral waters are considered. An interesting attempt of explaining the origin of thermal mineral waters by the example of the "sulfuric" water made in "Iadigar Daud" (Medical Book, 16th century) is described. Some terms (khashuri, tuti) referring to historical terminology are explained. The work is of interest from the standpoint of the chemistry of thermal mineral waters.

Keywords: Georgian mineral waters, historical aspects, chemistry of waters, terminology.

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The origin of shadow economy and the basic processes of its development in the transition period in Georgia are considered. It is noted that purposeful economic reforms are the guarantee of elimination of the shadow economy in all its manifestations. The possibility of reducing the shadow economy scale is considered in various aspects: statistical, macroeconomical and social. There is also considered Georgian Government policy aimed at establishment of special financial tools and economical conditions, including enhancement of the efficiency of governmental bodies, reformation of the state control system, regulation of the accounts, establishment of the system stimulating the legalization of shadow capital, etc.

Keywords: economy, shadow sector, legalization, reforms.

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There are considered basic criteria (orographic, hydrothermal, climatic, biotic, etc.) for determination of the natural potential of mountain landscapes, resource potentials of natural components, and reference natural territorial complexes, which demonstrate structural, functional and ecological features of the mountain landscapes. It is shown that, in each landscape, the natural potential is reflected in qualitative and quantitative indexes of the components and geomasses, but the social-economical potential - in the possibilities of exploitation of the territory, in comfortable of uncomfortable dosing of external factors, etc. Consideration of the variety of landscape potentials and their complex estimation are interesting from both scientific and practical standpoints.

Keywords: mountain areas, landscape, potential, geoecological features.

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