Abstract. In this work, a generalized mathematical scheme of random processes, with the help of which it is possible to describe a wide range of real queueing systems (data transmitting networks, computer systems, etc.) and to solve some problems of the reliability theory, is offered. The necessity in developing such a scheme has arisen in the connexion with an increasing sophistication of real automated control systems when the available methods do not cover all problem statements that interest a practical worker. So, it is necessary to develop an analytical apparatus capable to consider a great variety of active factors in order to create the models which fit the original adequately, i.e. are maximally approximated to the original.

Keywords: random processes, queue, waiting time, reliability, theory.

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A method of studying the turbulent modes of movement of the flow of optically transparent liquids is considered. The method is based on the measurement of intensity fluctuations of the modulated beam which take place in the flowing liquid. By special software the experimental data form sets of points in the appropriate phase spaces. The processing and analysis of the experimental data was carried out on the basis of fractal geometry and the «Gauss screen» model. With their help the fractal and correlation dimensions of the set of phase points have been calculated. The good concurrence of the values of these dimensions testifies to sufficient efficiency of the method. The experimental measurements were carried out on special installation, in which the various modes of the movement of a liquid were generated by thermal convection. For automation of the experiment control, measurement and data processing, the interface developed specially for the presented method was used. Its high characteristics provided for the reliability of the obtained results.

Keywords: convectional flows, liquid, optical methods.

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Methods of measuring the polarization of thermal neutrons are considered. A new method which allows us to measure the thermal neutrons polarization with high accuracy is presented. The method does not require additional devices which are usually used for these purposes and that makes it simple and reliable in operation.

Keywords: thermal neutrons, polarization, measurement method.

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A model of the magnetosphere of the Earth with consideretion of the twenty-four-hour orientation is presented. The dependence of the during a year on the daily state of the such dependence can be approximated by a periodic function. It is noted thet the total ozone concentration is also a periodic function, but not a hormonic one.

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

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Abstract. The technology of producing large, optically perfect, doped silver chloride crystals has been developed. These crystals are transparent within a wide range of the infrared spectrum, are resistant to powerful laser radiation, and are chemically resistant to the influence of aggressive media. The results of studying the grown crystals physical properties, such as microhardness, transmission and reflection in the wavelength range of 2.5-25 m m, are presented. Optical elements for atomic power industry and infrared optics have been produced.

Keywords: infrared optics, silver chloride, crystals.

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Abstract: The InP0.75As0.25 crystal has been grown. The material has strong optical absorption at l = 1.06 m m that enables us to produce a neodymium laser radaition receiver. The sharp absorption edge of the InPxAs1-x solid solutions also provides for creating a continuous stream of optical filters.

Keywords: semiconductors, absorption, receivers, optical filters, neodymium laser.

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Abstract. It is shown that application of pulse-photon treatment in the technology of fabrication of light-emitting structures allows to considerably lower the duration and temperature of crystal heating and improves the quality of ohmic contacts. A significant role of the ionization factor in the process of photostimulated diffusion in semiconductors is demonstrated.

Keywords: pulse-photon treatment, photostimulated diffusion, ohmic contact.

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The technology of fabrication of ohmic contats for photodetectors on the basis of porous silicon has been developed. The offered technology significantly improves the parameters of the mentioned devices. Electrochemical anodization of the contacts protects the devices from externalinfluence and perevents deterioration of their parameters by time.

Keywords: ohmic contacts, photodetectors, porous silicon, fabrication.

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A new microelectronic sensor for detection and rapid measurement of the mercury concentration in gases and liquids is presented. Principal metrological characteristics of the sensor are considered.

Keywords: sensor, mercury, concentration.

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The methodological scheme which contains the algorithm of the processe of designing highly reliable micro- and optoelectronic devices is consideed. The design route contains a single integral system consisting of subsystems. Search of the optimal version takes place in dependetly at each design stage and the results are united in the complete system.

Keywords: micro- and optoelectronic devices, design, methodological scheme, algorithm.

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A device of measuring the intraocular pressure is described. The device contains two indicators, one of which displays the intraocular pressure value (in mm Hg), and the other - the force (in grams). For measuring the pressure, the optical head end, on which an applanation area, i.e. a fiber-optics face-plate, is placed, is to be pressed to cornea of the eye under examination. The device is multifunctional: in the taring mode it can be used for mass examination of people's eyes, an elastotonometric curve can be plotted, etc.

Keywords: tonometer, fiber-optics face-plate, intraocular pressure.

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The solution of one general problem of synthesis of jointing mechanisms of sewing machines by given specifications is presented. By the example of a general flat six-link jointing mechanism, the solution of the stated problem by the method of point interpolation is demonstrated.

Keywords: sewing machine, synthesis of mechanisms, mathematical solution.

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The possibility of using the theory of convective transfer of a scalar substance of description of mass exchange processes in complex flows is demonstrated. The dependence of the marginal values of the electrical current density at the membrane on the hydrodynamic characteristics of the processed solution has been obtained. This dependence is valid in the first approximation at the laminar flow mode for any turbulizator (spacer) with transversal resistance to the flow.

Keywords: laminar flow, mass exchange,electrodialysis, desalination apparatus.

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A method of measuring the nonstandard physical values is considered. The algorithm of the method and the solution of the corresponding differential equations are presented.

Keywords: nonstandard physical values, measurement method, calculation, algorithm.

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The possibility of application of nonparametric measurements in the descriptive analysis of the observed maximum turbidity of the River Mtkvari at the site of Tbilisi (minor sampling) is considered. The constructed descriptive model is adequate both within the real range of variations in the observed maximum turbidity and within the range of the expected turbidity variation values. The offered model can be used at the stage of preliminary designing of the recreation and cultural zone on the River Mtkvari bank at the site of Tbilisi.

Keywords: descriptive turbidity model, cultural zone designing, prediction.

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The problems of compressed gas throttling among the connected pneumatic elastic elements of a multiaxis automobile are considered.

Keywords: pneumatic elastic elements, dissipation of energy, multiaxis automobile.

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The principle of operation and the basic equations for calculation of a new ejector device for lifting the river bottom drift are presented.

Keywords: bottom drift, lifting, ejector, calculation.

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A semiempirical method on the basis of which it is possible to determine the wave velocity at vertical upgoing motion of a three-component mixture in the shell regime is considered.

Keywords: three-component mixture, motion, vertical pipe, velocity, calculation.

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A method of estimation of vehicle economic efficiency on the specified route is considered. The vehicle is estimated by net profit with consideration of road and ecologic safety that allows us to choose efficient vehicles out of a great number of compared models.

Keywords: vehicle, economic efficiency, safety, estimation.

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The result of investigation on the possibility of improvement of birdproofness of aircrafts are presented. Heuristic methods have been used for evaluating the possibility of improvement of aircraft birdproofness. Application of laser radiation for these purposes is substantiated. In Appendices, the technical requierements to designing the devices preventing collisions of aircrafts with birds are given.

Keywords: aircrafts. birdproofness, improvement, collision.

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The work on designing the ship electrodialysis apparatus for distillate mineralization in order to obtain drinking water was carried out. The technological procedure for distillate electrodialysis mineralization was developed. The construction of the plant for distillate elctrodialysis mineralization (DEM) with the capacity of 50 m3/day has been designed. The experimental ship DEM plant was produced and tested on the stand. Drinking water obtained in the process of distillate electrodialysis mineralization practically satisfies the requirements of the State Standard on Drinking Water.

Keywords: distillate mineralization, electrodialysis, procedure, ship equipment.

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Mixed copper-zinc ferrites were synthesized by formula Cu1-xZnxFe2O4 at various x. Their true heat capacity in the 300-900K temperature range was measured. The heat capacity of the samples at x=0; 0.2; 0.4; 0.6; 0.8 was measured for the first time.

Keywords: copper-zinc ferrites, heat capacity.

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New technological procedures for production of pure metals by thermal dissociation of their oxides have been developed.

Keywords: production, pure metal, oxide.

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New chemical-thermal treatment technology of low-alloyed chromium which essentialy increased its heat resistance at high temperatures has been developed.

Keywords: treatment, chromium, corrosion.

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Li-containing forms of the natural (Rkoni deposit) and synthetic clinoptilolite have been prepared. The influence of concentration and temperature of LiCl solution on the ion exchange capacity of the samples have been studied. Samples with the highest content of Li (1.95 meqv/g) are obtained at the temperature 200-250^oC in 1N solution. Ion exchange processes for Na, and K cations on Li-containing forms clinoptilolite have been studied.

Keywords: zeolites, clinoptilolites, ion exchange, particularities.

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The results of thermal analysis of five zeolite-containing sedimentary rocks from some deposits of Georgia: analcime, lomonitite, phillipsite, clinoptilolite and mordenite, are presented. The maximum moisture content in terms of g/100g zeolite was determined. The analysis of the obtained derivatograms of the analyzed zeolite-containing rocks of Georgia has shown that they are identical to the most representative natural zeolites from some deposits of the USA, Bulgaria, India, Canada and Italy.

Keywords: zeolites, thermal analysis, comparison.

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Conversion of ethyl alcohol over the Ag-exchanged and decationed Y-tipe zeolites by a microflow method within the 200-2500C temperature range has been studied. It was established that the Ag-containing zeolite is an active and selective catalyst in the reaction of partial oxidation of ethanol with acetaldehyde formation whereas the HNaY zeolite is most active in intramolecular dehydration of alcohol to ethylene. A state of silver in the zeolite stucture was studied by X-ray and photoelectric spectroscopy (XPS). It was established that reduction of Ag+ to a metal state takes place. The increase in the intensity of the main peak in the XPS spectrum points to migration of Ag ions formed in the zeolite bulk to the surface. The conclusion that high activity and selectivity of the AgNaY catalyst in the ethanol oxidation reaction may be caused by the presence of isolated Ag ions or Ag associates.

Keywords: zeolites, catalyst, ethyl alcohol, oxidative dehydrogenation, dehydration.

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The problem of producing highly pure arsenic (V) oxide is considered. The investigation has shown that highly pure arsenic (V) oxide can be produced by oxidation of symmetric trialkylarsenites by gaseous chlorine with subsequent hydration of the intermediate product and, finally, dehydration of the recovered acid.

Keywords: arsenic (V) oxide, arsenic aldehyde, arsenic acid.

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By action of phenylhydrazine, from arsenous acid ether with general formula (RO)3As, elementary arsenic of high purity has been recovered. This method can become the basis for production of metallic arsenic necessary for the AIIIBV type semiconductors.

Keywords: arsenous acid ether, phenylhydrazine, recovery products.

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The formation of zinc fulvates in natural waters by the solubility method was studied. At pH 8 the composition ratio of the complex which formed in an aqueous solution was found to be 1:1. The mean value of the stability constant of zinc fulvates is (1.21± 0.14)∙106 (Mw=6300 in terms of the associate).

Keywords: zinc, fulvic acid, fulvate, stability constant, Leden method.

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The activation barrier (D D H#) and equilibrium constant of the ketoenole tautomeric process (KT) of acetaldehyde derivatives were calculated by the semiempirical quantum-chemical method AM1. It is shown that the process proceeds by the mechanism of the intermolecular hydrogen bond through a cyclic dimer of acetaldehyde.

Keywords: acetaldehyde, quantum-chemical method, ketoenol tautomerism, equilibrium constant, hydrogen bond, cyclic dimer.

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By the quantum-chemical semiempirical method AM1, the entalphy (D H), the ionization potential (I), the dipole moment (m ), and the atomic charge (qi) of 4-substituted imidazole were calculated. It is shown that the dependence of the induction constant of the substitute - s 1 has a linear character, but the dependence of the dipole moment on s 1 is of the second order.

Keywords: imidazole, tautomerism, quantum-chemical method, ionization potential, dipole moment, correlation analysis.

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The interaction of Bertollet’s salt with arsenic (III) sulfide in an aqueous-acidic medium has been studied. It is shown that the redox reaction products are diarsenic pentasulfide and arsenic acid.

Keywords: Bertollet’s salt, arsenic (III) sulfide, diarsenic pentasulfide, arsenic acid.

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The possibility of production of plugging compositions from SiCl4 and vat residues of its manufacture for selective isolation of water in oil wells is considered. It was established that the plugging compositions contain 2 to 10% of hydrolysing chlorine (=Si-Cl) and, under the influence of water during 20-30 minutes, they form waterproof gels.

Keywords: plugging compositions, oil wells, SiCl4.

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2-Phenyl-; 2-(4-chlorophenyl); 2-(4-bromophenyl) and 2-(4-metoxyphenyl)indole-3-aldehyde 4-(bezimidazole-2)-phenylhydrazones have been obtained by condensation of substitute 2-phenylindole-3-aldehydes with 2-(4-hydrazinophenyl)benzimidazole in the presence of acetic acid. The starting aldehydes have been prepared under conditions of the Vilsmeier reaction from the substituted phenylindoles with the excess of phosphorous oxychloride in dimethylformamide. The composition and structure of the products have been identified by the methods of physical and chemical analyses.

Keywords: indole, benzimidazole, condensation.

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The complexation reaction of lead (II) with monoethanolamine in ethylene glycol solutions has been studied by differential pulse polarography and chronovoltammetry. The composition of the complexes were determined; their stability constants at various ionic forces were calculated.

Keywords: lead (II) complexes, monoethanolamine, ethylene glycol solutions, complexation reaction.

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The equilibrium of formation of silver and cadmium cyanide complexes by the potentiometric method with application of amalgam cadmium and metal silver electrodes at 250C and the 1.0 ion power created by sodium perchlorate is investigated. It is shown that the silver and cadmium complexes with coordination numbers 3 and 5, respectively, are formed in the investigated solutions. Stability constants of the derived complexes (b n) at the ion power 1.0 and temperature 25^oC were calculated. The stability constants for complex Ag(CN)32- is b 3=4.17.1022; for Cd(CN)53- - b 5=3.61.1017.

Keywords: cyanide complexes, silver, cadmium, ethylene glycol solutions, investigation.

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The wine material sediment precipitated at a zeolite (clinoptilolite and mordenite) filter was analyzed by chromatography-mass spectrometry. Using the clinoptilolite filter, 62 individual compounds and, using the mordenite filter, 56 individual compounds were identified, respectively.

Keywords: wine Gareji, sediment, composition, analysis.

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Clostridium thermosaccharolyticum that takes part in non methane genic phase of anaerobic digestion of cattle breeding wastes was isolated from animal manure. These bacteria utilize cellulose decomposition metabolites and produce substrates for methane - forming bacteria. Morphologycal, physiologycal and culture properties of the abovementioned bacteria were studied.The optimum growth conditions were determined.

Keywords: anaerobic digestion, biogas, cellulolytic bacteria, Clostridium thermosaccharolyticum.

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Electroreduction of iron in the NaOH-MEA-Br3 system was investigated. The investigation has proved that the iron electroreduction process is of a catalytic character. Optimal conditions of iron discharge were determined by application of kinetic parameters of the process.

Keywords: iron, blood serum, electroreduction, polarography.

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A digital characteristic of effective functioning of endocrine glands has been developed within the scope of the quasi-contiguity matrices method.

Keywords: quasi-contiguity matrix, endocrine glands.

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The main physical and chemical properties of petroleum ether and its fraction isolated from a straight-run petrol fraction of the commercial oil mixture from Samgori (Georgia) oil collecting point are studied. The isolated distillates with b.p. 40-70^oC and 70-100^oC (petroleum ether) and 30-800C (petroleum ether fraction) by their characteristics (density, fraction composition, group hydrocarbon composition, sulphur and water content, etc.) actually correspond to the quality indexes of commercial hydrocarbon solvents. In addition to the standard values, the characteristic boiling point, the pressure of saturated vapour, the heat of vaporization, the solvent ability, etc. were determined for the isolated solvents. The possibility of production of hydrocarbon solvents (petroleum ether and its fraction) from the straight-run petrol fraction of Georgian oil-mixture is demonstrated.

Keywords: petroleum products, petroleum ether, petroleum ether fraction, Samgori (Georgia) oil-mixture.

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The main physico-chemical properties of extractive petrol and a rubber solvent isolated from a straight-run petrol fraction of the commercial oil mixture with low sulphur content from Samgori (Georgia) oil collecting point are studied. Isolated distillates with b.p.70-950С and 80-1100С by their characteristics (density, fraction composition, group hydrocarbon composition, sulphur content, etc.) actually correspond to the quality indexes of commercial hydrocarbon solvents. After the treament by concentrated sulphuric acid, the fraction with b.p. 80-1100С was completely dearomatizated. In addition to the standard values, the characteristic boiling point, the pressure of saturated vapour, the heat of vaporization, the solvent ability, etc. were determined for the isolated obtained solvents. The possibility of production of hydrocarbon solvents (extractive petrol and a rubber solvent) from the staight-run petrol fraction of Georgian oil-mixture is considered.

Keywords: extractive petrol, rubber solvent, Samgori (Georgia) oil-mixture.

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Simulative organizational-technological and financial-economic models of the activities of a construction organization as an object of the two –level management system are considered. The construction organization directorate, under competence of which the development of the current operative plans falls, acts in the capacity of a managerial body of the lower level. The association management, which approves planning figures, lays down economic norms and deals with strategic marketing, acts in the capacity of the managerial body of the higher level.

Keywords: construction industry, organizational-technological model, financial-economic model, interrelation, management.

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Some aspects of public health of Georgia under the transient period conditions are considered. The first results of the public health reform in Georgia are presented. The measures for further improvement of the medical insurance and the public health system under specific economic conditions are offered.

Keywords: economy, public health, insurance, analysis, development.

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