SUMMARY

CHOLESTERIC LIQUID CRYSTAL MIXTURES SENSITIVE TO SOLAR IRRADIATION

Aronishidze M.N., Chanishvili A.G., Chilaya G.S., Khatiashvili A.A., Petriashvili G.Sh., Tavzarashvili S.P. and Tevdorashvili K.G.

Institute of Cybernetics

Cholesteric liquid crystal mixtures sensitive to different parts of the solar UV irradiation are presented. The mixtures are intended for the use in detectors and dosimenters of the solar UV A (320-400 nm), UV B (290-320 nm) and UV C (shorter than 290 nm) irradiation. The principle of the effect is based on photoisomerization of the molecules of either nematic host or the optically active dopant. Under the UV exposure, the pitch of the cholesteric and, therefore, the peak of selective reflection (color) of the liquid crystal layer changes. The change in the color depends on the dose of light irradiation and characteristics of liquid crystal materials.

Keywords: cholesteric liquid crystals, UV sensors, solar irradiation.
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ON THE THEORY OF A CYLINDRICAL RADOME

Asanidze A.V., Kevanishvili I.G. and Tskhakaia K.G.

Georgian Technical University

The approximate theory of a cylindrical radome with a round cross-section, the side-wall of which is a dielectric layer of certain thickness, is outlined. The transmitting antenna is located on the cylinder axis. The optimum mode of the effect of radiation aside was determined. The problem of determination of external and internal radiuses of the radome is formulated. The conditions under which the radome has maximum transparency were determined. There is offered the formula for computation of the external radius of the radome, which provides the maximum transparency depending on dielectric layer permitivity and wavelength.

Keywords: radome, permitivity, antenna, transmission.
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MODELING OF THE PHENOMENON OF ANNIHILATION OF THE EARTH'S MAGNETIC FIELD IN THE VICINITY OF THE FRONTAL POINT OF THE MAGNETOSPHERE

Ghurtskaia N.V.

M.Nodia Institute of Geophysics

The semispherical model of the daylight side of the Eearth's magnetosphere is considered. A simple kinematic model of the solar wind plasma flow is used. It is assumed that, in the vicinity of the frontal (focal) point of the magnetosphere, the initial dipole magnetic field of the Earth does not depend on the geomagnetic latitude. Due to the annihilation of the geomagnetic field because of the interaction with the southern component of the interplanetary magnetic field transported by the solar wind, the radial component of the magnetic field is generated in the vicinity of the frontal point of the magnetosphere. As a result, characteristic values of the electric potential difference along the geomagnetic longitude are estimated.

Keywords: solar wind, magnetosphere, interplanetary magnetic field, electric potential difference.
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ON A SIMPLE MODEL OF PLANE WAVES OF THE IDEAL LIQUID IN A POOL OF A FINITE DEPTH AND WITH A FREE SURFACE

Tvalchrelidze A.K.

Kutaisi Technical University

A one-dimensional theory of plane waves of the ideal liquid in a pool of a finite depth was constructed. The basis for this theory is the kinematic hypothesis that allows determining uniquely vertical movements of liquid points by their horizontal movements. The basic differential equation of the theory and the boundary conditions were derived using the d'Alembert-Lagrange principle. The theory is applied to investigation of wave processes in the surf zone of the sea, where the bottom profile and inertial forces play a major part.

Keywords: surf zone, wave model, method of hypotheses, ideal liquid.
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INVESTIGATION OF SOME PROPERTIES OF SECOND-ORDER SYMMETRICAL COMPOSITION DESIGNS FOR FOUR VARIABLES

Beraia N.O., Zedginidze I.G. and Kvanchiani A.O.

Georgian Technical University

There were studied the mostly spread properties of second-order symmetrical composition designs for four variables both without adding points in the design center and with central points, taking into account the accuracy of measuring instruments used. The design distortion was achieved by adding a randomly generated value to each element of the design. By the twenty designs obtained in that way, twenty values of the criterion under investigation were computed for each α, which enabled us to construct the corridor of errors and to make a decision about reducing a number of decimal places at determination of the optimum value of the "star" branch corresponding to a particular criterion. Computational equations for covariant matrix elements are also presented.

Keywords: experiment design, symmetrical composition designs.
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COMBINED METHODS OF IMAGE CODING

Kharatishvili N.G., Chkheidze I.M and Gogilashvili Z.J.

Georgian Technical University

There are suggested the methods of increasing the efficiency of coding images and their sequence, which are based on the combination of a modified morphological pyramid with other methods of reduction: optimum quantization of pyramid levels; fast Fourier transformation (FFT), interframe differential pulse-code modulation, and interframe interpolation. A comparison of the efficiency of the suggested combined methods of coding was performed on the basis of graphical interpretation according to which the coding method that allowed obtaining the specified index of reduction at satisfying the precision indexes of image reconstruction could be chosen. From the obtained graphs it is also evident that an increase in the index of reduction in a wide range (9 to 120) is accompanied with certain stability of the change in the signal-noise peak ratio (only by 2 dB). This points to high efficiency of the developed combined methods for coding of dynamic images.

Keywords: image coding, efficiency, morphological pyramid, reduction, fast Fourier transformation, interframe differential pulse-code modulation, interframe interpolation.
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GENERATION OF SHOCK WAVES AT THE COLLISION OF PLATES

Chkhartishvili I.V., Abkhazava N.S., Gamsakhurdia J.V., Khundadze T.G., Chkhartishvili D.I. and Dolidze N.G.

Institute of Metallurgy and Metal Science

Generation of shock waves at the collision is the result of superposition of plain (presonic) plastic waves. Therefore, actually the shock wave generation takes place at some distance from the contact surface of the collision. There are proposed the methods of determination of the transition zone width prior to the shock wave generation and of the critical pressure value that is necessary for the shock wave generation. The stricture of the transition zone deformed by a plain (presonic) plastic wave differs from the rest part of the sample obtained under the conditions of treatment with shock waves.

Keywords: shock wave, transition zone, generation, collision of plates.
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SYSTEMS FOR MONITORING THE WORKING SUBSTANCE LEAKAGE FROM CIRCULATION LOOPS OF POWER PLANTS

Kashia V.G., Kadaria M.A. and Zhvania I.A.

I.Vekua Sukhumi Physical-Engineering Institute

The problem of monitoring the tightness of circulation loops of nuclear power plants (NPP) is considered. It is demonstrated that the universal method of monitoring the working substance leakage from the circulation loops, developed in Sukhumi Physical-Engineering Institute, allows detecting the leakage of the working substance of any type under any conditions and reducing the adverse effect of working substance components on the environment. The combined version of the universal method of monitoring the tightness of circulation loops containing alkaline metals allows not only detecting the moment of leakage initiation, but also utilizing the atoms of the outflowing metal.

Keywords: nuclear power plant, circulating loop, working substance, leakage, tightness, monitoring system.
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FEASIBILITY OF EXECUTION OF A JOB BY AN ENGINEERING SYSTEM WITH STRUCTURAL AND TIME REDUNDANCY

Chkhaidze N.Z., Chumburidze T.Z. and Makasarashvili D.G.

Georgian Technical University

There are presented the results of the probability analysis of the capacity of the duplicated system, the elements of which are subject to failures depreciating partially or completely the results of the job executed by the system before a failure has occured. Probability-time characteristics of feasibility of execution of the job in a definite time were obtained in terms of operational transformations.

Keywords: engineering system, redundancy, execution of a job, failure, probability analysis.
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PROBABILITY ANALYSIS OF SOME SPECIFIC MATHEMATICAL MODELS OF QUEUE SERVICING

Koplatadze M.R. and Kupatadze T.G.

Georgian Technical University

The probability analysis of some specific mathematical models of queue servicing with variable intensity and memory is presented. There were studied mathematical models of the systems in which the entering flow intensity or the servicing intensity depend on a certain value of a queue, on the number of failures and on the previous conditions of the system.

Keywords: mathematical model, queue, servicing, failure, probability analysis
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LOGICAL BASES AND ARCHITECTURE OF MODULAR SYSTEM: TECHNOLOGY FOR DESIGNING ENERGY CARRIER DISTIBUTION CHAINS

Kervalishvili M.P., Mkheidze T.D., Chkonia M.G. and Chakhvashvili L.A.

Georgian Technical University

Distributed systems and differentiated service networks are the most appropriate when different types of traffic can be associated with different network services and, thus, to different quality levels.

In the systematic development of distributed systems it is necessary to use basic system models such as the interface view, the distribution view, and the state transition view. Each of these fundamental parameters is very helpful and plays an important role in the system development process. For large systems, the development is carried out through several levels of abstraction.

The transition way from abstraction to particular distributed system logistics and architecture is based on Supervisory Control and Data Acquisition System (SCADA) technologies. At the same time, for such kind of development processes of the modular systems it is essential to estimate and select the refinement steps, which gives the possibility to build up the effective multilevel and multidimensional integrated distribution.

Keywords: modular systems, energy carriers, distribution chains, logistics.
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ON THE POSSIBILITY OF INCREASING THE EFFICIENCY OF DIGITAL SYSTEMS OF RAILWAY AUTOMATIC EQUIPMENT AND COMMUNICATION

Beridze A.P. and Elizbarashvili P.M.

Georgian Technical University

Some problems of application of the results of the sampling theory in digital systems of railway automatic equipment and communication are considered. There are also presented estimations of the stability of corresponding expansion operators for various systems of basic functions when the computational errors are of a determinate and stochastic character. The application of the results of the sampling theory in practice promote the increase in the efficiency of digital systems in the railway operation.

Keywords: railway automatic equipment, digital systems, efficiency, sampling theory, expansion operator, computational stability.
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MANAGEMENT EFFECTIVENESS OF THE GAS SUPPLY SYSTEM AND THE GAS DISTRIBUTION COMPANY

Kherodinashvili I.Sh.

Hydroproject Institute

There are discussed the conditions of the problems of application of the theory of management to gas distribution system and gas distribution companies (GDC), including system approach principles.

Keywords: gas supply system, management effectiveness.
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TECHNOLOGICAL CHARACTERISTICS OF THE GAS DISTRIBUTION SYSTEM

Kherodinashvili I.Sh.

Hydroproject Institute

There are considered technological characteristics of the gas distribution system, characteristic features of the technological process and basic estimation indexes of the technological characteristics. The technological characteristics were worked out using the system approach with account of basic requirements to the gas distribution system.

Keywords: technological characteristics, gas distribution system.
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KIRCHHOFF EQUATION FOR A SINGLE-PHASE TRANSFORMER

Museliani T.G.

Georgian Technical University

The problem of formulation of an adequate Kirchhoff equations of a single-phase transformer is considered. Generally the direction of mutual induction emf is chosen arbitrary. We assume that mutual induction betweeen inducing and induced currents is positive. It has been established that, in a double-wound single-phase tranformer, self-induction emf are always negative and impede changes in loop currents, but mutual induction emf are always positive and facilitate changes in loop currents. In a multiwinding single-phase transformer, the self-induction and mutual induction emf between secondary currents are negative, are directed in one direction and impede the changes in loop currents, whereas the mutual induction emf between the primary and secondary windings are positive and facilitate the changes in loop currents.

Keywords: transformer, inductivity, mutual induction, electromagnetic inertia.
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THE EQUATIONS OF LOOP CURRENTS OF INDUCTIVELY COUPLED CIRCUITS

Museliani T.G.

Georgian Technical University

There is considered the problem of elimination of significant errors being made at formulation of sets of equations of loop currents for inductively coupled electric circuits because of inadequate mathematical interpretation of Ampere's rule and the Lenz law of electromagnetic inertia. There have been formed the equivalent, the equation of adequate loop currents, and the corresponding matrix of path resistance for the electric circuit consisting of an emf source, a capacitance and three inductively coupled coils set on a three-rod core.

Keywords: transformer, inductivity, mutual induction, equivalent, electromagnetic inertia.
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THE CONTENT OF IMPURITIES ON THE CYLINDRICAL SURFACE OF GAS PHASE MONOCRYSTALLINE TUNGSTEN

Zykov B.M. and Nardaia Yu.I.

I.Vekua Sukhumi Physical-Engineering Institute

By the method of secondary ion mass spectrometry, the chemical content of near-surface impurities was determined on the cylindrical surface of gas phase monocrystalline tungsten, which is used as a material for the emitter of thermoemission converters (TEC) in space nuclear power stations.

Keywords: gas phase monocrystalline tungsten, cylindrical surface, impurities, thermoemission converter, emitter.
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REMOVAL OF SURFACE IMPURITIES FROM THE CYLINDRICAL SURFACE OF GAS PHASE MONOCRYSTALLINE TUNGSTEN

Zykov B.M. and Nardaia Yu.I.

I.Vekua Sukhumi Physical-Engineering Institute

By the methods of electron Auger spectroscopy and diffraction of slow electrons, the chemical content of near-surface and surface impurities were determined on the cylindrical surface of gas phase monocrystalline tungsten, which is used as a material for the emitter of thermoemission converters (TEC) in space nuclear power stations.

Keywords: gas phase monocrystalline tungsten, cylindrical surface, impurities, thermoemission converters, emitter.
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CESIUM ON RESIDUAL OXYGEN OF THE TUNGSTEN COATING ON THE NIOBIUM-ZIRCONIUM ALLOY

Zykov B.M. and Nardaia Yu.I.

I.Vekua Sukhumi Physical-Engineering Institute

Adsorption of cesium on the substrate in the initial state, i.e. at n_min of residual oxygen, the oxygen loosely bound to the substrate consolidates first. Then, on that O and O located among the islands of intermetallic suboxide Nb₂W₂O on the lower level of the relief, bonding of O with Cs takes place. Besides, Cs also combines with molecules of the Nb₂W₂O sample due to catalysis of the molecule of subbronze Nb₂W₂OCs. At the same time, on the substate areas cleared from O at its consolidation, on the polarized bond Cs from the flow is adsorbed. That cesium metallizes at reaching sufficient n on less defective (smooth) areas. Besides, Cs can extract O from some volume defects not containing C or W₂C. The molecules of W₂C in other volume defects are screened by Cs without a chemical bond. On a small amount of residual CO, Cs hardly adsorbs. Displacing superfluous O from the area where Cs forms the chemical bond with O to the areas where that bond is impossible, Cs stimulates formation of secondary molecules of W₂O there. That formation is likely to take place in linear defects such as terrace grooves. At heating of the film with φ_min, the following processes take place. Due to small n of O and nonuniform distribution of adsorbates, which is related to their impeded migration on the rough relief, at low temperatures (up to 150ºC) redistribution of Cs and unbound O takes place. It causes migration of the mentioned Cs and O in the form of CsO molecules not bound chemically to the substrate from the upper level to lower ones. As this happens, compounds W₂OCs are formed on the intermediate level in the grooves of terraces and W₂OCs - on their bases. On the lower level mixed film NbW₂OCs + NbCOCs is formed. At the same time, the excessive O for formation of compounds with Cs is displaced to linear defects where formation of the secondary W₂O molecule is possible.

Keywords: niobium-zirconium alloy, tungsten coating, residual oxygen, cesium.
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HEATING OF THE FILM WITH CESIUM OF THE TUNGSTEN COATING ON THE NIOBIUM-ZIRCONIUM ALLOY

Zykov B.M. and Nardaia Yu.I.

I.Vekua Sukhumi Physical-Engineering Institute

At heating of the film in the interval of 150-375°C, on the intermediate level of the relief, due to different sizes of islands, gradual destruction of W₂OCs, W₂COCs and secondary W₂O takes place, which increases n of Cs, unbound in compounds to the substrate, and partially of O there. As a result, because of limitations on the area for deconsolidation of adsorbates on the terraces, at 250°C the Cs, which is weaker than O held by the substrate, is displaced to the upper layer, which is free of adsorbates. At 325°C desorption of Cs from that level starts and enhances even more at 375°C. Complete desorption of Cs from that level occurs at 600°C with continuous entering of Cs due to decomposition of the compounds on the lower level. Immediately after desorption of Cs on the upper level, there enters O from the intermediate level. But after complete desorption of Cs from the defects with O at 700°C, a part of that O enters the lower level. That process is most intensive after heating up to 900-1000°C. Besides, after decomposition of W₂COCs, especially at the boundaries of the terraces with the lower level of the relief, a part of COCs can transfer from the intermediate level to the lower level when E decreases. This optimizes n of the NbCOCs molecules in compounded film NbW₂OCs + NbCOCs, especially if there has not been sufficient O for their formation even at sufficient n in the C defects. The efficiency of that process is evidenced eventually by complete transfer of COCs from the intermediate level to the lower one at 375°C. At 1150°C the release of O from volume defects of the lower level to the upper one begins. It is possible to decrease its n on the upper level with the help of a few bursts at ≥ 1600°С. In this case, due to recrystallization of the sample material and diffusion of Nb from the substrate to the W coating, n of Nb₂W₂O increases on the lower level. Thus, the effect of Cs on the substrate in the initial state is minimized at 1100°C and, without considering formation of additional CO, at 700°C.

Keywords: niobium-zirconium alloy, tungsten coating, cesium, heating.

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METHODS OF CONTROLLING THE LASER RADIATION FOR MULTICOMPONENT ANALYSIS OF HUMAN EXHALATION

Davarashvili O.I., Enukashvili M.I., Kekelidze N.P., Iakobashvili M.M., Agaev F.F., Aliyev A.V., Emekli N., Yarat A. and Emekli E.

Iv. Javakhishvili Tbilisi State University

Institute of Pulmonology, Ministry of Health, Azerbaijan

Marmara University, Istanbul, Turkey

Different approaches to the multicomponent analysis of human exhalation are discussed. There is demonstrated the possibility of composing a database for medical diagnostics by laser diode spectroscopy.

Keywords: multicomponent analysis, human exhalation, laser diode spectroscopy, database.
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PRODUCTION OF BORON CARBIDE BY CARBOTHERMAL REDUCTION OF BORIC ACID

Abzianidze T.G., Shalamberidze S.O., Gelashvili G.Sh., Bairamashvili I.A., Kekelidze L.I. and Chkhikvishvili V.B.

Georgian National High Technology Center

The results of the experimental studies on carbothermal reduction of boric acid are presented. The results provide the opportunity to make the following conclusions: boron carbide obtained by the method of carbothermal reduction of boric acid shows high purity; metallic impurities do not exceed 0.1 % wt. Boron carbide powder contains a lot of needle-like crystals of 20-100 μm sizes, and it needs grinding for further application for sintering and hot compaction. Independent of boric acid content in the initial mixture, the carbothermal reduction method provides obtaining boron carbide with ratio B:C>4 (typical ratio B:C=3.8). Boron carbide obtained by carbothermal reduction contains some quantity of free carbon.

Keywords: boron carbide, boric anhydride, boric acid, carbon, carbothermal reduction.
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ON THE POSSIBILITY OF INCREASING THE SPEED AND ACCURACY OF INSTRUMENTAL ANALYTICAL MEASUREMENTS

Dolidze V.A., Tsintsadze G.V., Kutsiava N.A. and Eristavi V.D.

Georgian Technical University

There are considered some possible ways of increasing the speed and accuracy of predicting the result of the inertion process of the analysis on the basis of the measurement data signal of inertion-type sensors (pH-meters) at the initial stage of the transition process. Destabilization factors were studied at high temperature and stability of the system in time.

It is demonstrated that normalization of time constant values is possible only after completing the registration of these values. The distribution of the probability density obeys the normal law. The value of the time constant deviation decreases exponentially at approaching the time of reaching the static mode of measurement by the system. The basic approach to increasing the speed of measurements basing on predicting the transition mode is minimization of random values of oscillation amplitudes and the operation period of the recorder. The composed prediction algorithm is in agreement with the experimental results and satisfies the requirements to designing measurement instrumentation.

Keywords: analytical measurements, instrumentation, speed of operation accuracy.
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POTENTIOMETRIC DETERMINATION OF THE ION ACTIVITY IN SOILS USING ION-SELECTIVE ELECTRODES

Dolidze V.A., Tsintsadze G.V, Kutsiava N.A. and Eristavi V.D.

Georgian Technical University

Some capabilities of the potentiometric method with the usage of ion-selective electrodes (ISE) for soil analysis are considered. The advantage of the activity method over the methods commonly used for determination of the substance concentration is shown. By the example of determination of the Ca ions in situ, high representability of the obtained results as compared with the measurements in a soil suspension is justified. The results obtained with the help of ISE correlate well with the data characterizing the changes in the exchange Ca concentration, which were obtained at absorbing Ca by ion-exchange resins.

The Ca ions activity depends on the CO₂ concentration, which represents the total effect of breathing of plant roots and microorganisms in soil. So, the daily cycle of the biological soil activity is determined.

The capabilities of ISE of various designs are considered. The advantages of a thin-layer silver-chloride electrode for determination of the Cl^- ions are demonstrated. The electrochemical chains and the experimental data on the selectivity for the ions of NO₃^-, SO₄², CO₃^2-, HCO₃^2‑ and PO₄^3- are presented.

The choice of conditions for the ionometric measurements is aimed at standardization of soils by their humidity and does not take into consideration their dispersion. Thus, it is necessary to normalize the analyzed sample by its dispersion (to the size of the particle ≥ 1 mm).

Ionometry can also be useful in solution of theoretical problems associated with the energy of sorption processes in soil, the dynamics of ion-exchange processes, hydration, etc..

Keywords: soil, ion activity, ion-selective electrodes.
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ADSORPTIVE PROPERTIES OF SOME NATURAL CHABAZITES

Eprikashvili L.G., Kvariani K.M., Burjanadze M.N. and Kordzakhia T.N.

P.Melikishvili Institute of Physical and Organic Chemistry

Adsorptive properties of some natural chabazites were investigated by water vapors using the exsiccation method. The specimens were from the Gomareti Plateau (Georgia), Nikolaevsk-on-Amur (Russia), and the State of Oregon (USA). A comparison with the results of thermographic investigations of those specimens was made. The specimens from Georgia and Russia were characterized by low contents of a zeolite mineral in contrast to the American specimen, which contained a significant amount of the zeolite mineral (~90%). It is demonstrated that chabazites are not only interesting objects for investigation of selective adsorption, but they are also rather promising for application as molecular sieves and effective adsorbents - desiccants.

Keywords: zeolites, natural chabazite, adsorptive, properties.
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DESICCATION OF MONOATOMIC ALCOHOLS С₂ – С₅ON SOME NATURAL ZEOLITESOF THE CHABAZITE GROUP

Eprikashvili L.G., Kvariani K.M., Andronikashvili T.G. and Kordzakhia T.N.

P.Melikishvili Institute of Physical and Organic Chemistry

There was studied the process of desiccation of normal monoatomic alcohols С₂ – С₅ using natural zeolites: chabazite and erionite, under dynamic conditions. The analysis of experimental results demonstrated that, though the erionite also has a three-dimensional system of channels, it is more wide-porous zeolite than the chabazite. The competing adsorption between the alcohol and water molecules proceeds to a greater extent, decreasing the properties of molecular sieves of the erionite. Thus, the erionite is characterized by worse desiccative ability that the chabazite. The latter can be used for desiccation in the monoatomic alcohol-water systems along with clinoptilolite, mordenite and phillipsite.

Keywords: desiccation, natural zeolites, chabazite, erionite, monoatomic alcohols.
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SYNTHESIS OF SOME NEW BIS-PYRIDAZINOINDOLES

Samsonia N.Sh., Targamadze N.L., Mumladze E.A., Chikvaidze I.Sh. and Samsoniya Sh.A.

Iv. Javakhishvili Tbilisi State University

Annelation of indole and pyridazine nuclei results in formation of the properties of derivatives of these heterocycles. Among the derivatives of pyridazinoindoles, there are found a lot substances which have high biological activity and can be used in pharmacology.

The investigations in the aim to synthesize the derivatives of bis-pyridazinoindoles are of serious interest. We have synthesized new heterocyclic compounds – bis(3,4-dihydro-4-oxopyridazino[4,5-b]-5H-indole-8-il)oxide, 3,3^'-diphenylbis(3,4-dihydro-4oxopyridazino[4,5-b]-5H-indole-8-il)oxide and bis(3,4-dihydro-4oxopyridazino[4,5-b]-5H-indole-8-il)methane.

2,2^'-Diethoxycarbonyl-3,3^'-diphormyl-bis(5-indolyl)oxide and 2,2^'-diethoxycarbonyl-3,3^'-dip-hormyl-bis(5-indolyl)methane were used as raw compounds. During boiling of these compounds with hydrazinehydrate or phenylhydrazine in icy acetic acid, the corresponding bis-pyridazinoin-doles are formed.

Apparently, the reaction proceeds in two stages. The corresponding bishydrazones formed at the first step undergo cyclization at the expense of the intermolecule nucleophyl attack of amino nitrogen of a hydrazone group.

Keywords: heterocyclic system, bis-pyridazinoindoles, synthesis, investigation, diformyl-bisindoles.
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SYNTHESIS OF SOME NEW BIS-PYRIDAZINOINDOLES

Samsonia N.Sh., Targamadze N.L., Mumladze E.A., Chikvaidze I.Sh. and Samsoniya Sh.A.

Iv. Javakhishvili Tbilisi State University

Annelation of indole and pyridazine nuclei results in formation of the properties of derivatives of these heterocycles. Among the derivatives of pyridazinoindoles, there are found a lot substances which have high biological activity and can be used in pharmacology.

The investigations in the aim to synthesize the derivatives of bis-pyridazinoindoles are of serious interest. We have synthesized new heterocyclic compounds – bis(3,4-dihydro-4-oxopyridazino[4,5-b]-5H-indole-8-il)oxide, 3,3^'-diphenylbis(3,4-dihydro-4-oxopyridazino[4,5-b]-5H-indole-8-il)oxide and bis(3,4-dihydro-4oxopyridazino[4,5-b]-5H-indole-8-il)methane.

Keywords: heterocyclic system, bis-pyridazinoindoles, synthesis, investigation, diformyl-bisindoles.
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SYNTHESIS OF SOME DIHYDRAZONES AND DIOXIMES IN A SERIES OF BIS (5-INDOLYL) OXIDE AND BIS (5-INDOLYL) METHANE

Targamadze N.L., Samsonia N.Sh., Chikvaidze I.Sh., Esakiya N.A. and Samsoniya Sh.A.

Iv. Javakhishvili Tbilisi State University

Aromatic hydrаzones and derivatives of indole oximes have a broad spectrum of pharmacologic activity. Besides, they are used in a fine organic synthesis as intermediate compounds.

We have synthesized some indole dihydrazones and dioximes; 2,2’-diethoxycarbonyl-3,3’-diformyl-bis(5-indolyl)oxide(1) and 2,2’-diethoxycarbonyl-3,3’-diformyl-bis(5-indolyl)-methane(2) were used as the initial compounds. Some reactions of condensation (addition-elimination) of these compounds with phenylhydrazones and hydroxylamines were carried out.

The condensation of dialdehydes 1 and 2 with phenylhydrazines was carried out at room temperature and pH 4-5. The corresponding dihydrazones were obtained with high yields.

The interaction of dialdehyde 1 with 2,4-dinitrophenylhydrazine was carried out under harder conditions caused by the low reactive-ability of the latter.

By the interaction of dialdehydes 1 and 2 with hydroxylamine in a neutral medium, the corresponding dioximes were obtained with high yields.

Keywords: dihydrazone, dioxime, bisindolyloxide, bisindolylmethane, dialdehyde bisindolylmethane, dialdehyde bisindolyloxide.
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CORRELATIONS IN 7-AZAINDOLES

Zarqua T.Sh., Gelozia Sh.V., Kereselidze J.A. and Tsikolia M.A.

Iv. Javakhishvili Tbilisi State University

By means of semiempirical quantum-chemical method AM1, the values of the atomic charge (q_i), the ionization potential (I), the dipole moment (µ), the orbital energy (E) and the bond orders (P_ij) of the 4-substituted 7-azaindoles were calculated. As a result of the analysis of distribution of the charge on carbon atoms, it was revealed that the charge decreases in a line: q₅>q₃>q₂>q₆>q_4. The dependences of physical-chemical characteristics on Hammet’s and induction constants of the substitute were constructed. It is demonstrated that Hammet’s and induction constants of the substitutes qualitatively equally describe the electronic structure of these compounds.

Keywords: 7-azaindoles, correlation, atomic charge, potential of ionization, dipole moment, bond orders, orbital energy, quantum-chemical method.
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HERBICIDAL AND FUNGICIDAL ACTIVITY OF PHOSPHORORGANIC COMPOUNDS WITH A FIVE-MEMBERED CYCLE

Samkharadze L.O., Balarjishvili G.I., Magdeeva R.K. and Dolidze A.V.

P.Melikishvili Institute of Physical and Organic Chemistry

There were synthesized some compounds with herbicidal and fungicidal activity: 2,2,2-trichlor-1-oxyethylcyclopentylphosphinic, 1-hydroxycyclopentylcyclophosphinic and 1-hydroxycyclohexylcyclopentylphosphinic acids, magnesium salt of alkylcyclopentylphosphonous acid, and 2-methylcyclopentylphosphonic acid. At testing the latter exhibited 100% nematocidal activity against the saprozoic nematode, like Heterophos and Carbation.

Keywords: phosphororganic compounds, synthesis, herbicidal activity, fungicidal activity.
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LEACHING OF THE REDUCED MASS OF BARITE CONCENTRATE

Tsintsadze G.V., Andguladze Sh.N. and Gaprindashvili V.N.

Georgian Technical University

Development of the regime of production of barium-containing solutions of the concentrations satisfying industrial specifications (110-120 g/l) at maximum extraction of water-soluble barite salts from the reduced mass is one of the important stages of the process of production of barite concentrate. The effects of temperature, time, and the L:S ratio on the degree of BaS leaching were studied. Basing on the experimental results, we dwelled on the leaching regime corresponding to the fourth step: ξ₁=75ºC; ξ₂=4.80; ξ₄=16.5 min. Under those conditions, the BaS concentration in the solution made up 118 g/l at BaS extraction equal to 92-93%. Such solutions can be used in production of lithopone and various barium compounds, as well as for purification of open-cut acid waters of Madneuli Mining-Concentrating Integrated Works from heavy metal ions.

Keywords: barite concentrate, reduced mass, leaching.
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CHEMICAL AND THERMOGRAPHIC ANALYSES OF AN INDUSTRIAL NICKEL-CONTAINING DEAD CATALYST FOR PURIFICATION OF COMBUSTION GASES

Ioseliani D.K., Gigilashvili Ts.V., Dolidze A.V., Naskidashvili Ts.I., Kalabegashvili N.G. and Balarjishvili G.I.

P.Melikishvili Institute of Physical and Organic Chemistry

Rustavi Stock Company "Azot"

There were carried out thermographic and chemical analyses of an industrial nickel-containing dead catalyst in the process of purification of combustion gases from cyanide and carbon monoxide. It is demonstrated that at low temperature (40-80°С) volatile carbonyl compounds, in particular Ni(CO)₄, are formed. As a result, the amount of the active component - nickel in the catalyst decreases by 20-50%. Correspondingly, the service life of the catalyst reduces. At temperatures higher than 120°C, the amount of nickel in the catalyst decreases insignificantly. Basing on the obtained results, optimum conditions of the process were determined: temperature of 150-250°С and 100% purification from cyanide and carbon monoxide. There were performed thermographic analyses of initial, reduced and spent samples of the catalyst. The results of the analyses are in agreement with the results of X-ray analyses.

Keywords: nickel-containing catalyst, analysis, combustion gases, purification.
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THE EFFECT OF THE INITIAL CONCENTRATION OF ACTIVE SILT IN THE SILT BLEND AND THE DEPTH OF SEDIMENTATION ON THE KINETICS OF ITS COMPRESSION

Zalikashvili Z.O., Kakushadze T.S. and Chkenkeli B.J.

Georgian Technical University

The experimental investigation allowed us to reveal some regularities of active silt compression in the process of gravitational separation of silt blends. There are presented the curves of the kinetics of active silt compression and the dependences of active silt compression on the rate of interface reduction. Their analysis demonstrated that, when the rate of sedimentation of the interface was V_p>2, an abrupt increase in the concentration of compressed active silt was observed.

There is proposed a principle according to which a more compressed structure of the active silt is formed by intensification of its compression using smooth mixing when the range of recommended speeds of pivots affecting the silt is from 0.1-0.2 cm/s for pivots of d=17mm to 2-4mm/s for pivots of d=50-100mm. The values of the parameters affecting the silt compression kinetics were determined experimentally.

Keywords: silt blend, active silt, separation, compression kinetics, sedimentation depth.
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EXPERIMENTAL INVESTIGATION ON TECHNOLOGICAL SCHEMES OF OPERATION OF CLARIFIERS WITH A SUSPENDED LAYER OF ACTIVE SILT

Zalikashvili Z.O., Kakushadze T.S. and Chkhenkeli B.J.

Georgian Technical University

There are presented the investigation results on the operation of a silt separator and a clarifier with a suspended layer of active. The presented two-stage scheme of separation of silt blends allows decreasing the carry-over of suspended substances with clarified water to 3-5 mg/l without prolongation of the total duration of sedimentation. At the same time, these indexes remain the same at increased amounts, up to 3 g/l, of active silt in the silt blend entering for separation from aerotenks. There is proposed a technological scheme of biological purification of waste waters with preliminary silt separation and clarification in the suspended layer of active silt.

Basic possible ways of intensification of biological purification using two-stage silt separation are briefly considered.

There are also presented experimental results on technological schemes of clarifiers with a suspended layer of active silt. It is inferred that application of two-stage silt separation with water clarification in the suspended layer of active silt in the system of biological purification allows efficient maintaining of the necessary silt age in the system.

Keywords: waste waters, purification, active silt, separation, clarifier, technological scheme.
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THE MICROELEMENT CONTENT IN THE WATERS AND SUSPENSIONS OF THE KHOBI RIVER AND ITS TRIBUTARIES

Davitaia T.N., Supatashvili G.D., Gvakharia V.G. and Sulamanidze N.D.

Iv. Javakhishvili Tbilisi State University

A. Janelidze Institute of Geology

There has been studied the distribution of microelements (F, I, As, Cu, Zn, Pb, Mn and Fe) in the waters and suspensions in the Khobi River and its tributaries during a year. The minimum concentrations were observed in the spring-summer period, the maximum concentrations – in the autumn or the winter. A rather stable content of iodine in the waters of the Khobi river basin can be explained by a high iodine content in atmospheric residuals in that region. A low content of fluorine in the abovementioned waters is related to the existence of carbonite rocks in the river basin. The heavy metals migrate generally in a suspended state.

Keywords: microelements, suspensions, river waters, dissolved forms.
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BACTERIAL MEMBRANE FRAGMENTS AS PHAGE DNA EJECTION STIMULANTS

Ivanova A.T., Mdzinarashvili T.J., Khvedelidze M.M., Tediashvili M.I., Janelidze N.T. and Mrevlishvili G.M.

Iv. Javakhishvili Tbilisi State University

G. Eliava Institute of Bacteriophages, Microbiology and Virology

The first steps of phage-bacteria interaction (phage adsorption on membrane fragments and DNA ejection from the phage) on the model system consisting of a phage and bacterial membrane fragments were investigated. The membrane fragments from E.coli with the presented active receptor system were obtained by ultrasound disintegrartion (sonication). Using the viscometric method, the DNA ejection from the phage capsid into the solvent was observed. The viscometric investigations were carried out under alkaline conditions, because in this case less aggregation of the bacterial membrane fragments was observed. It is demonstrated that the specific viscosity of the suspensions of of both the phage and the membrane fragments is almost zero. The specific viscosity increase with time (a kinetic process) occurs only in the case of the phage - membrane fragments complex. The kinetic process, in its turn, is the phage adsorption on the bacterial membrane fragments and the DNA ejection from the phage into the solvent.

Keywords: phage, bacterial membrane fragments, adsorption, DNA ejection.
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TRANSDERMAL DRUG DELIVERY:
I. PASSIVE TRANSDERMAL THERAPEUTIC (TRANSDERMAL PATCH) SYSTEMS

Burjanadze N.G.

Institute of Physical Chemistry, University of Münster, Germany

Nowadays development of a new chemical entity requires investments of millions of dollars and 20 years of time. This is one of the reasons why the development of drug delivery systems (DDS) has become increasingly important. DDS represent a different approach which concentrates on increasing the therapeutic effeciency of available drugs by optimizing their formulation and design in line with their therapeutic aim. Transdermal drug delivery systems (TDDS), which especially involve application of drug release control technologies, have been an active field of the DDS development since the late 1970s because of their therapeutic advantages.

In the framework of joint research and development partnership with pharmaceutical companies, Nitto Denko has used its original drug formulation technology, whereby a wide array of adhesive polymers with varied physicochemical properties are optimally matched to the type of the drug involved, for development of a series of TDDS, which contribute in the everyday practice of medical care. The present paper reports on the evolution and future potential of this original drug formulation technology, the result of a rigorous commitment to a particular line of research with particular reference to the problem of drug release control.

Keywords: drug delivery, transdermal therapeutic system, patch, drug release control.
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TRANSDERMAL DRUG DELIVERY:
II. ACTIVE TRANSDERMAL THERAPEUTIC SYSTEMS

Burjanadze N.G.

Institute of Physical Chemistry, University of Münster, Germany

Since 1979, when the Food and Drug Administration approved the first transdermal drug delivery system (Transderm Scop^® Patch), there has evolved a successful alternative to systemic drug delivery. Despite their relatively higher cost, transdermal delivery systems have proved to be advantageous for delivery of selected drugs, such as estrogens, testosterone, clonidine, nitroglycerin, scopolamine, fentanyl, and nicotine. Compared to oral dosage forms, these systems offer not only improved patients compliance, but also superior uniformity of drug concentrations in plasma throughout their application. Most transdermal patches are designed to release the active ingredient at a zero-order rate for a period from several hours to several days after application to the skin. This is especially advantageous for prophylactic treatment or maintenance therapy in chronic conditions when, otherwise, the patient has to carry around oral medications and to remember to take them several times a day. The development of long-acting, extended- or sustained-release oral medications is beneficial in such cases. However, these dosage forms are to be taken at least once a day compared with transdermal patches that can extend drug release for up to seven days (e.g., Catapres-TTS^® or Climara^®). Earlier, parenteral delivery was the only alternative for the drugs that were inactivated by gastrointestinal enzymes or gastrointestinal pH, and could not be given orally (e.g., estrogens, testosterone and nitroglycerin). These drugs can now be delivered directly into the systemic circulation by a non-invasive transdermal route through well-designed patch systems. It is most important that, unlike injectables, drug therapy can be interrupted by removal of the patch at any desired time if toxicity develops. More recently, enhanced percutaneous delivery of charged hydrophilic drugs has become possible by using iontophoresis. Electric current is applied to the skin, which provides the driving force to enable penetration of ions into the skin. Similarly, phonophoresis uses ultrasonic energy for enhancing drug penetration into the skin. These approaches require special devices and training, and their use is currently restricted to medical clinics and hospitals. These and other active transdermal therapeutic systems are discussed in this paper.

Keywords: drug delivery, active transdermal systems, iontophoporesis, ultrasound.
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A METHOD FOR RAPID ANALYSIS OF SOIL CORROSION

Klimiashvili L.D. and Tsikhelashvili Z.I.

Georgian Technical University

A method for rapid analysis of soil corrosion is considered. The method involves two affiliated procedures: automatic electron and ion microscopies. The results of studying the automatic electron current relation are presented. The proposed method allows one to evaluate approximately such a commonly accepted index of soil corrosion as mass loss.

Keywords: soil corrosion, rapid analysis, electron microscopy, ion microscopy.
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SOME ISSUES OF THE STRATEGY OF PLANNING THE RESTORATION OF PIPELINES OF MUNICIPAL WATER-SUPPLY NETWORKS

Primin O.G. and Klimiashvili L.D.

Georgian Technical University

The possibility of development of an algorithm for the strategy of planning the restoration of pipelines of municipal water-supply networks is considered. The procedure of selecting potential objects of municipal water-supply network for restoration is described.

Keywords: municipal water-supply networks, pipeline restoration, strategy, planning, algorithm.
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ON THE PROBLEM OF OPTIMIZATION OF IRRIGATION OF AGRICULTURAL LANDS

Sturua T.G.

Georgian Technical University

Rehabilitation of irrigated agricultural lands and their sufficient water supply are basic conditions for rising their productivity and, thus, the crop yield. The available mathematical models cannot describe adequately the present situation in the irrigation system of Georgia. For the purpose of rehabilitation of irrigation systems in Georgia, we have developed a mathematical model which allows us to determine the variables satisfying the restrictions to the utmost and providing the maximum efficiency function. The developed model is the mathematical model of a nonlinear efficiency function with a nonlinear system of restrictions.

Keywords: agricultural lands, irrigation, mathematical model.
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COMPARATIVE CHARACTERIZATION OF DRY WINE MATERIALS PREPARED BY DIFFERENT METHODS

Ebelashvili N.V. and Sirbiladze A.L.

Research Institute of Horticulture, Viticulture and Wine-Making

Test and reference samples of dry pink table wine materials prepared by different methods were the subject of investigation. At the moment of effervescent fermentation, to freshly pressed sulfited (80 mg/dm³) pomace of red grape Saperavi, the mixture of the runoff and first press of grape Rkatsiteli was added in the amount (by volume) 3 times as much as the amount of the wort pressed from the red grape pomace; to freshly pressed pomace of red grapes Tavkveri and Asuretuli Shavi (separately), the same amount (by volume) of the same wort of grape Rkatsiteli was added. The reference samples were prepared by fermentation of the Rkatsiteli wort on the fermented pomace of the abovementioned red grapes. Alcoholic fermentation was performed according to classic production process of red table wines.

It was established that, using freshly pressed pomace of red grapes, it was possible to prepare dry table wine materials of better quality. In the samples prepared with the use of freshly pressed pomace of red grapes, the mass concentration of anthocyans, titrate acids and total extract, and the color intensity index are higher, and the concentration of volatile acids is lower than in the samples prepared using the fermented pomace of the same red grapes.

Keywords: wine materials, pink table wines, production process.
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ENOCHEMICAL INVESTIGATION OF WINE MATERIALS FOR PINK SPARKLING WINES

Ebelashvili N.V.

Research Institute of Horticulture, Viticulture and Wine-Making

The method of preparation of wine materials for pink sparkling wines is suggested. In the process of effervescent fermentation, to freshly pressed sulfated pomace of red grape Tavkveri, the mixture of the runoff and first press of white grape Rkatsiteli was added in the amount twice as much as the wort pressed from the Tavkveri pomace. Alcoholic fermentation was performed by the classic production process of red wines.

In test wine materials, the content of spirit made up 11.2-11.7% (by volume); titrate acids - 5.8-6.2 g/dm³; volatile acids - 0.46-0.52 g/dm³; pH=3.34-3.40; total phenols 0.62-0.76 g/dm³; anthocyans - 58.2-80.5 mg/dm³; leucoanthocyans - 185-226 mg/dm³; monomeric phenols - 80.2-115.5 mg/dm³; total extract - 17.8-18.8 mg/dm³.

The results of enochemical investigation point to correct selection of process parameters and justify typicalness and good quality of the of the prepared wine materials for production of pink sparkling wines.

Keywords: wine materials, pink sparkling wines, production process, enochemical investigation.
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ON THE NECESSITY IN THE DEVELOPMENT OF MICROELECTRONICS IN GEORGIA

Chikovani R.I. and Jojua N.O.

Georgian Technical University

The decisive importance of microelectronics in the development of the technical level of information servicing of the human society is noted. The specific features of microelectronic technology, which determine economical indexes of this field, are considered. Basing on the literature data, it is demonstrated that the development of electronics has a profound impact on overcoming economic crises by small countries. The importance of the development of microelectronics in Georgia is analyzed. Favorable conditions and factors promoting its development are mentioned. In Georgia, there is keen intellect, high industrial potential and experience in the field of microelectronics. Considering the depressed situation in the field of electronics in Georgia, there is emphasized that some essential measures should be taken for development of microelectronics in the conditions of market economy in the country.

Keywords: microelectronics, development, economy of Georgia.
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КРАТКИЕ СООБЩЕНИЯ

THE DIAGNOSTICS OF DISEASES ON HUMAN EXHALATION BY USING IR LASERS:
PROBLEMS AND POSSIBLE DECISIONS

Davarashvili O.I.,Enukashvili M.I., Kekelidze N.P., Yakobashvili M.M., Abdullayev F.D., Agayev F.F., Aliyev V.A.,Emekli N. and Yarat A.

Iv. Javackhishvili Tbilisi State University

Institute of Pulmonology, Ministry of Health, Azerbaijan

Marmara Univerity, Istanbul, Turkey

Problems of composing the data-base and improving laser parameters for wide clinical application of the diagnostic method on human exhalation are discussed. There is considered the systematic approach focusing on the choice of basic and specific components in exhailed air for different diseases. A special doping of laser active regions for decreasing threshold current is also noted.

Keywords: diagnostics of diseases, human exhalation,database, IR lasers, operating temperature.
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ON THE SELECTION OF INDEXES OF OPERATIONAL RELIABILITY OF COMPLEX SYSTEMS

Chkhaidze N.Z.

Georgian Technical University

There are considered the most typical functions of Automatic Management System (AMS) and the corresponding modes of its operation: management information exchange among the AMS users; solutions to information-computational problems and problems of mathematical simulation; information provision for management bodies; database exchange among the AMS users; exchange of faximile information etc.

The mean-time-between-failures and the average recovery time are the most efficient indexes for estimating the reliability and maintainability of the system. The indexes of availability and operational availability should be taken as a generalizing index of system reliability.

Keywords: automatic management system, reliability, operation, indexes.
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DEVELOPMENT OF A CORRELATION ANALYZER FOR NONDESTRUCTIVE DIAGNOSTICS OF PIPELINES

Klimiashvili L.D.

Georgian Technical University

A new correlation analyzer for nondestructive diagnostics of pipelines is proposed. In contrast to available analogs, this instrument allows analyzing a graphic curve at the signal subtractor output. The curve results from mutual subtraction of the two functions reflecting correlation spectra of acoustic signals.

Keywords: correlation analyzer, pipeline, nondestructive diagnostics.
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ON THE NATIONAL STANDARD OF SPECIFIC ELECTRICAL CONDUCTIVITY OF ELECTROLYTIC SOLUTIONS

Mujiri J.N., Buleishvili M.I., Getsadze G.J., Khabuliani L.I., Beridze N.G. and Khuchua L.U.

National Institute of Metrology and Standardization

For assurance of uniformity of measurements, a standard and a hierarchical chain of specific electrical conductivity (SEC) for propagation of the national standard to lower units of the hierarchical chain both by direct measurements and the comparison method were developed. The existence of the national standard and the hierarchical chain have promoted metrological provision of conductometric measuring instruments in Georgia.

Basic parameters characterizing the SEC standard and the following: the range of electrolytic solutions within which realization of the unit takes place makes up 0.1-10 mho/m; the estimated random error of realization of the SEC unit, expressed in terms of a standard deviation of the measurement reading, is less than 3×10^-4 at ten independent observations; the estimated probable systematic error of realization of the SEC unit is less than 8×10^-4.

Keywords: electrical conductivity, electrolytic solutions, national standard, hierarchical chain.
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REFERENCE MATERIALS OF SPECIFIC ELECTRICAL CONDUCTIVITY IN A WIDE MEASUREMENT RANGE

Buleishvili M.I., Getsadze G.J., Khabuliani L.I. and Beridze N.G.

National Institute of Metrology and Standardization

Development of reference materials for metrological provision of conductometric measuring instruments is very important. Despite quite extensive data on conductometric investigations of nonaqueous electrolytic solutions, they cannot be recommended as reference materials. The nonaqueous solutions are not stable enough, and electrolytes are deficient and hardly amendable to synthesis.

We studied electrolytic solutions on the basis of mixed solvents-water-dioxane. These solutions appeared to be suitable as reference materials by a number of properties. On the basis of the mentioned system, there were developed standard materials of specific electrical conductivity for the measurement range of 1·10^-3-1·10^-9 over the temperature range of 293.15-323.15K.

Keywords: reference materials, electrical conductivity, electrolytic solutions, national standard.
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