Basing on the dynamic equilibrium equation for a variable-mass body, an equation of the steady liquid flow with variable mass for the case of variable discharge that smoothly changes on the way has been derived. The possibility of applying the differential equation for prizmatic channels for determination of the parameters of the variable-mass flow when the liquid flows in perforated pipelines is considered.

Keywords: liquid flow, variable discharge, general equation.

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A partial differential equation for the landslip surface on the rock slope shifting ground has been derived with consideration of such mechanical characteristics as the angle of internal friction and adhesion. By solving the corresponding system of common differential equations, a complex function determining the slip surface of the landslip has been formed. Basing on the equations of continuous media mechanics, the derivation of the dynamic equation for the landslip is presented.

Keywords: landslip, slip surface, rock slope, differential equations.

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On the base of the analysis of natural factors promoting the occurence of snow avalanches, there has been established the generalized criterion condition of static steadiness/unsteadiness of a snow blanket and occurence of a snow avalanche on a mountain slope under the influence of the rain water infiltration at the bottom area, the earth shock and the wind.

Keywords: snow avalanche, motion, velocity, shearing force, calculation.

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A diffraction method for calculation of permitivity of variconds is presented. The method is based on а diffraction phenomenon of an E-polarized electromagnetic wave on the infinite long cylinder with periodical structure along the axis direction.

Keywords: diffraction, cylinder, permitivity, variconds.

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A strict solution of the problem of diffraction of a plane electromagnetic wave on the infinite cylinder with the periodical structure along the axis direction is presented.

Keywords: diffraction, cylinder, periodical structure.

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The theoretical investigation of electromagnetic matching in the main branch of the aperture-coupled T-junction is presented.

Keywords: waweguide, matching, T-junction.

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E.Andronikashvili Institute of Physics

The lattice statics method was used to obtain the general expressions for the relaxation energy and distortions of a multiatomic lattice containing isolated point and dipole defects. The Coulomb interaction was taken into account according to the Ewald method. The expression for the Coulomb part of the dynamic matrix was obtained. The distortion fields formed in the presence of the dipole defects of two kinds in the conducting planes of ceramic superconductors are analyzed.

Keywords: point defects, dipoles, dynamic matrix, lattice distortions, ceramic superconductors.

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The structural state of titanium carbide strongly depends on the conditions of its production. To establish various conditions for producing massive samples of titanium carbide, the following methods were employed: plasmic refine, self-extending high-temperature synthesis (SEHTS), vacuum-thermal activation, and explosion. Electron-microscopic investigation showed that, in the samples produced by plasmic refine, SEHTS and explosion, cubic titanium carbide with the structure NaCl(s -TiC) is mainly observed. Besides, new structural states of titanium carbide were noticed. One of these phases corresponds to a hexagonal state of titanium carbide with a stoichiometric formula Ti₆C₅. In the samples produced by plasmic refine, besides the mentioned hexagonal phase, polytype structures of a 6H type formed by ordering the packing defects were observed. In the sample produced by vacuum-thermal activation, which was baked at 1450⁰C and thermally treated at 1000⁰C, a cubic superstructural phase Ti₂C formed by ordering the carbon vacancies was observed.

Keywords: titanium carbide, structure, properties.

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High-strength bainite ductile cast irons are a new-type constructional material. Total output of the bainitic ductile cast iron has been continuously increasing. However, utilization of the latter is essentially limited that is caused by the strict conditions which the casts should satisfy and by the lack of technology of producing the austempered ductile iron (ADI). The authors have elaborated a new type of the cast iron from which cast wares, including the wares, processed by pressure (forging, stretching, punching, pressing etc.) can be produced. The structural transformations were investigated.

Keywords: deformable graphite, ductile cast iron, bainite, austempering.

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The electrooptical characteristics of room-temperature BP II with positive dielectric anisotropy were studied. The reversible red shift of the Bragg peak up to 60 nm was observed.

Keywords: liquid crystals, blue phases, Bragg diffraction, electrooptics.

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The relationships for determining the geometric parameters of initial surfaces of the gears with a variable gearing relation have been obtained. The obtained relationships can be applied to the gears with constant gearing relation as well.

Keywords: gear, initial surface, geometric parameters.

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The results of the hydrodynamic investigation in desalination electrodialysis apparatus cells are presented. The experimental data give an idea of the structure of the flow at its turbulization and at small Reynolds numbers. The theoretical estimation of the flow turbulization effect on ion transfer in the electrodialysis cells at various profiles of concentration distribution are presented.

Keywords: electrodialysis apparatus, water desalination. flow turbulization, mass exchange.

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On the basis of a finite elements method and mechanics of a viscid incompressible liquid, the mathematical model of sea waves dynamics in a sea coastal zone has been constructed.

Keywords: finite element, model, waves, sea coastal zone.

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A reliable method of information transmission from the basic structure of a hydroelectric plant is considered. The block-diagram of transmission is presented. Communication with the computer is effected via optocouplers which are connected to the power transmission line by an executive mechanism. Application of the couplers provides for galvanic isolation of electric circuits that conduces to reliable operation. The logic of computer operation on receiving the data and affecting the executive mechanisms is considered.

Keywords: hydroelectric plant, active load, water flow rate, computer-aided control.

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The problem of improving the reliability of process control systems at chemical-engineering plants is considered. In paticular, the problem of improving the computer reliability using informational redundancy is studied in detail. Interval availability and its limiting value have been determined.

Keywords: reliability, failure, recovery, interval availability, informational redundancy.

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The unconventional method of determining the interval and limiting availability with consideration of the reliability of the equipment controlling the basic operational unit serviceability is considered.

Keywords: reliability, control, failure, recovery, availability.

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Statistical reliability indexes of the chemical-engineering system (CES) for production of nitric acid at Rustavi Production Association "Azot" are investigated. Calculation of the values of statistical and operational reliability characteristics of all components of the CES under consideration allow to determine real reliability level of the CES in whole.

Keywords: chemical-engineering system, reliability, statistical indexes, failure, production of nitric acid.

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It is justified that, under conditions of multistructural managing, for reducing the nomenclature and quantity of means of mechanization of agriculture, it is necessary to design so-called adaptive machinery. Adaptivity means fitness of machines to biological objects, landscapes, infrastructure of production of agricultural products, machinery, and services. An adaptive automotive gear designed for farms of Georgia is described. Principal trends in fundamental theoretical research, realization of which is essential for creating the basis for designing the new-generation adaptive machines, are discussed.

Keywords: agricultural machinery, adaptation, theoretical problems.

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Institute of Cybernetics

A device for measuring the light beam motion has been designed. In the device, fiber-optic components were used for scaling up the object motion and collecting the light flux. Application of a multielement phocon allows to improve the device sensitivily, all other factors being equal.

Keywords: optron, block diagram, fiber optics, light spot, filter, signal, detector.

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Some characteristics of the Earth are presented, that is essential for explaining the changes in the atmospheric ozone concentration. As in the weather forecast, besides other factors, the ozone concetration value plays a certain part, the negative influence of human activities on this characteristics is noted.

Keywords: weather, magnetosphere of the Earth, atmospheric ozone.

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By interaction of nickel (II) and cobalt (II) chlorides with guanidine citrate, the compounds of the formula (GunH)₂[M(Cit)₂]Ч 2H₂O (where Gum - guanidine; M=Ni(II), Co(II); Cit - citrate ions) were synthesized. The crystals of the syntesized compounds were investigated by X-ray structure analysis.

Keywords: synthesis, citrate metalates, guanidine, X-ray structure analysis.

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Interaction between transition metals salts and guanidine and citric acid were studied. The compounds (GunH)₄ [M(L)₂]Ч nH₂O (where Gun is guanidine; L - citrate ions; n=0-2; M - 3d-metals) were synthesized. Basing on the analysis of physical and chemical properties, the consideration about the complex compound structure was stated. Conditions for obtaining the crystals suitable for X-ray structure analysis were determined.

Keywords: synthesis, transition metals, complex compounds, guanidine, citrate.

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Humic acids isolated from natural waters (Lake Paravani) were investigated by infrared (IR) and ¹³C nuclear magnetic resonance (NMR) spectroscopy. The results of investigation showed that, in humic acids isolated from fresh surface waters, there exist hydrogen-bonded hydroxyls, aliphatic C-H, primary alcohols, and methyl and methylene groups bonded to carbonyl groups.

Keywords: humic acids, infrared spectroscopy, ¹³C nuclear magnetic resonance.

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Humic acids isolated from natural waters were investigated by thermogravimetric analyses and IR spectroscopy. The IR spectra of the preparations heated up to different temperatures were recorded and compared with the initial sample spectra. In the curves of the thermogravimetric and differential-thermal analyses, there were observed one endothermal effect (at 110-120⁰C) and three exothermal effects at 300⁰C, 510-530⁰C, and 670⁰C, respectively. It was determined that the investigated humic acids have a two-part structure.

Keywords: humic acids, thermogravimetry, differential-thermal analyses.

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By treating the products of interaction of soluble salts of some d-metals (III) and meta- or para-nitrobenzoylhydrazides with a tetrathioarsenic acid solution, as the result of the exchange reaction, tri(meta-, para- nitrobenzoylhydrazide) tetrathioarsenates were extracted from the mother solution. The composition and assumed structural formulae of the synthesized complex compounds were determined basing on IR spectral, thermal and chemical analyses, and investigation of molecular conductivity.

Keywords: metal, complex, nitrobenzoylhydrazide, tetrathioarsenate.

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By oxidation of the products of interaction of soluble cobalt (III) salts and hydrazides of carboxylic acids with air oxygen, cobalt (III) trihydrazide complexes were derived. By interaction of cobalt (III) hydrazide complexes and tetrathioarsenates, as a result of an exchange reaction, cobalt (III) hydrazidetetrathioarsenates were extracted. The composition and assumed structure of the synthesized complex compounds were studied by chemical and IR spectral analyses.

Keywords: complex, hydrazide, tetrathioarsenate, cobalt.

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Catalytic activity of nickel (II) and cobalt (II) complexes with diethylnicotinamide (DENA) in the presence of sodium boranes has been studied. It was established that the catalytic activity of the complex is caused by formation of low-valent complexes of nickel (II) and cobalt (II) with DENA, i.e. by formation of a homogeneous catalyst.

Keywords: complex, catalyst, diethylnicotinamide, sodium boranes, nickel, cobalt.

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P. Melikishvili Institute of Physical and Organic Chemistry

Chromatographic properties of the comparatively short quartz column (15mX0.53 mm) coated with methylsilicone elastomer SE-30 have been studied. The experimental data have been compared with those obtained on the metallic column (50 mX0.25 mm) coated with the same phase. It is shown that changes in geometric characteristics of the column (a threefold decrease in the column length and a twofold increase in its diameter) did not reduce its efficiency. By separating characteristics, the above column is in no way interior to a metallic column coated with the same stationary phase and can be successfully used in analytical practice for separation of the complex mixtures of organic compounds.

Keywords: separation, chromatography, compound mixtures, methylsilicone elastomer.

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For the first time, the possibility of using lomontite as an additive to soil was studied in order to reveal its adsorptive properties concerning the basic elements of mineral fertilizers. The obtained experimental results show that application of lomontite as an additive to the grey-brown soil improves holding of NH₄⁺ in comparison with clinoptilolite, and as regards to the K⁺ cations and the PO₄^3- anions - the results are almost identical.

Keywords: mineral fertilizers, lomontite, soil, holding of elements, selectivity.

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P.Melikishvili Institute of Physical and Organic Chemistry

For the first time, there have been determined experimental series of the selectivity of lomontite (from the deposit near Tbilisi, Georgia) in both initial and hydrogen forms in reference to the cations of alkali-earth metals and magnesium. The effect of zeolite heating on the selectivity in reference to the mentioned cations was also studied. It is shown that heating of the zeolite (initial anf hydrogen forms) up to 80⁰C does not cause any significant changes in the selectivity series.

Keywords: lomontite, selectivity, alkali-earth metals.

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The energies of Cu(II) and Pb(II) ions binding to C-phycocyanin were determined from their binding isotherms by equilibrium dialysis and atomic absorption spectroscopy. The binding constants of Cu(II) and Pb(II) ions with C-phycocyanin are 1.6Ч 10⁵ М ^-1 and 3.0 Ч 10⁵ М ^-1, respectively.

Keywords: lead (II) ion, copper (II) ion, C-phycocyanin, binding constant.

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The most part of exogenous U¹⁴C-phenol absorbed by Lemna minor sterile plants binds with the low-molecular peptides and proteins while the small part of it transforms via cleavage of the aromatic ring.

Keywords: Lemna minor, phenol, detoxification.

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Experimental results of the investigation of various statins in cholesterol-lowering therapy of patients with coronary heart disease. It was established that Atorvastatin, which significantly decreased the content of cholesterol (total cholesterol - by 30%, low-density cholesterol - by 46%) and triglycerides (by 23%), gives the most beneficial effect. Application of Atorvastatin obviously provides for improvement of the patients' clinical state and the life quality without undesirable adverse effects.

Keywords: atorvastatin, hypercholesterolemia, coronary heart disease.

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Formation of iridescent films, which increase the glass surface conductivity, is considered in interconnection with the composition and conditions of thermal treatment of the glasses in the systems Li₂O-MnO-B₂O₃ and Li₂O-MnO-B₂O₃-TiO₂. The study of the temperature dependence of the surface conductivity for glasses of various compositions, which had undergone thermal treatment under different temperature and time conditions, showed that the activation energy values were constant and the lgr _S values depended on the content. The conclusion about the pre-determining role of glass structure differentiation due to substitution of Li₂O for MnO and TiO₂ that results in formation of nonstoichiometric manganese compounds and increase in surface conductivity values has been made.

Keywords: glass, system, conductivity, energy, composition, thermal treatment.

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A flavonoidal pigment has been isolated from the apple fungus. A phenolic compound - hispidine was obtained from the pigment. It was established that the pigment is not toxic and can be applied as a dye in textile industry.

Keywords: pigment, identification, hispidine, isolaltion, dye, chromatography.

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Main physical and chemical properties of hydrocarbon solvents - Nefras C50/170 and white spirit isolated from a straight-run petrol fraction of commercial oil mixture from Samgori (Georgia) oil-collecting point are studied. The isolated distillates with b.p. 50-170⁰C and 150-200⁰C by their characteristics (density, fraction composition, group hydrocarbon composition, sulphur and water contents, etc.) actually conform to the quality indexes of commercial hydrocarbon solvents. In addition to the standard values, the characteristic boiling point, the saturated vapour pressure, the vaporization heat, the solvent ability, etc. have been determined for the obtained solvents. The possibility of production of the hydrocarbon solvents (Nefras C50/170 and white spirit) from the straight-run petrol fraction of Georgian oil-mixture is shown.

Keywords: petroleum products, hydrocarbon solvents, Nefras C50/170, white spirit, Samgori (Georgia) oil-mixture.

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Basing on investigation of various samples of pear and honey spirits, their extracts and aromatizated fractions by gas chromatography, there were revealed the volatile components that determine the individual features of raw materials. These data will allow to find new approaches to the development of high-quality beverages production technologies and, together with other control measures, to solve the problem of their distinguishing from similar falsified products.

Keywords: gas chromatography, pear spirit, honey spirit, origin by a raw material, differentiation, falsification.

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The content of nitrous compounds in honey and the products of its alcoholic fermentation have been studied. There were identified aminoacids which were present in honey, honey wine materail, and sediment-residue after distillation. Total nitrogen and amine nitrogen were determined in the same samples. It was established that, as the result of alcoholic fermentation of the honey products, the content of total and amine nitrogen in the honey material decreases that is caused by the action of pure-culture yeasts and their transformation.

Keywords: honey, nitrous compounds, alcoholic fermentation, aminoacids, chromatography.

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An algebraic characteristic of effective functioning of organelles has been developed within the scope of the quasi-contiguity matrices method.

Keywords: organelles, quasi-contiguity matrix.

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The data obtained with the use of the Wilcockson criterion appeared to be sufficient for rejecting the zero hypothesis or accepting the alternative hypothesis for the two-side criterion. However, calculations carried out for the single-side criterion produced the positive result at the significance level of a =0.05.

Keywords: chemistry, education, computer program, Wilcockson criterion, experiment, statistic data processing.

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A brief history of basic stages in development of the theory of evolution from the Darvin's law of natural selection to the necessity in applying the artifitial selection is presented. Special consideration is given to the fact that modern science does not extend the Darvin's theory of evolution to evolution of micro- and macrophysical systems on a cosmic scale. The conflict between the religion and the science in the approach to establishing the truth is considered.

Keywords: evolution, development stages, artificial selection, Darvin's "Demon", information, self-organization of energy-information work.

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Jerusalem is considered as a physical reflection of the cultures and architectural styles of periods, religions and nations that governed it over the centuries.

Keywords:condominium, standardized neighborhood, neo-orientalism, Brutalizm, pergola.

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There are described stages of master plan development and particular town-planning methods in architecture of Jerusalem

Keywords: town-planning, master plan.

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A conception of development of the city center with consideration of evolution of the local style and its inherent industrial features is presented.

Keywords: architecture, city style, neoclassicism, postmodernism.

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For increasing the volume of investments, it is necessary to elaborate business plans of prospective objects on a high professional level. General procedures for making business plans for investment projects through utilization of informational technologies are described. There are distinguished three stages of formation of a business plan:

preliminary: examination of a business idea;

elaboration of a financial plan;

estimation of expected risk factors;

beginning of the investment and starting the business.

The experience of making the business plan in the agricultural sector by an adopted computer program was employed.

Keywords: investment project, business plan, risk factor.

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To ensure the stability and reliability of Georgian banking system, the National Bank of Georgia carries out the measures of prudential regulation of commercial banks activities. In spite of some progress in the banking activities, it should be noted that the part of the banking system in providing the country economy with monetary resources is, unfortunately, rather limited that is caused by the existing level of banks capitalization, the influence of shadowy economy, and a number of other factors. To our opinion, it is reasonable to seek the way out of the present situation in complex evaluation of the banking activities basing on the analysis and scientifically justified methodology. The offered efficiency complex evaluation, that is based on the system of indexes, plays a decisive part in ensuring the stable and reliable functioning of the banking system as a whole.

Keywords: commercial banks, complex evaluation, financial indexes.

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The distributed system of processing and analysis of the acounting-statistic data by object-oriented designing, that is under development, is presented. There have been determined basic tasks of processing the statistic observation results that transform the offered system into the environment of developing such supplements as business accounting, personnel records, planning-financial calculations, special statistic services, etc. The system processes random statistic documents: applications, reports, patients' records, etc., irrespective of their form, contents, language, etc. Applications can include industry, agriculture, public health, education, museums, fiscal services, etc.

Keywords: distributed system, data processing, business activities, statistic observation, application.

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The problem of revision of the road taxes for the vehicle owners with consideration of the total weight factor, the engine power, and the correction coefficient is considered. Such approach to the problem will allow to establish fairer road tax rates.

Keywords: vehicle, road taxes.

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The significance of competition for the success of small and medium business is considered. The problem of gaining the competition advantage is presented. The principles essential for gaining and keeping such advantage are described.

Keywords: small business, medium business, competition.

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Basic criteria defining the market are considered. Basing on the experience of the leading companies, the successfull strategy of enterprises on the world market is briefly described.

Keywords: small business, medium business, market, consumer. 

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