PCSS, V.5, N1, 2004

Abstracts


V.G. Lytovchenko

Diamond-Like Carbon Films as the Base of Creation Electronic Devices of a New Generation
(review)


Institute of Semiconductor Physics NAS of Ukraine,
45, Nauki Av., Kyiv, 03028, Ukraine

The physical base formation the diamond-like carbon (DLC) films from RF-CH4 plasma and optical and structural parameters obtained material have been analised.The field of application of DLC films (antireflection coating for solar cells, tip-like electron field emission cathods, displays, HF transistors etc.) have been summerized. Such devices are stable at hard radiation, under mechanical and electrical overloading. The technological equipment for preparation of diamond (D) and diamond-like films, fabrication of the tip-array matrix was developed, and perspective of application was described.


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G.A. Sukach1, A.V. Bushma1, Yu.M. Gavrilyuk2, D.O. Olifirenko2

Determination of Overheating Temperature of Active Region in Semiconductor Emitters with Potential Barriers

1State University of Information and Communication Technologies
7, Solomjanska Str., Kyiv, 03110, Ukraine
2Institute of Economics and New Technologies
24/37, Proletarskaya Str., Kremenchuk, 39600, Ukraine

The methods and devices for determination of overheating temperature of active region in the light-emitting diodes (LEDs) and lasers DT are considered during their operation with a pulse current as power supply. The contact and indirect methods of DT definition are considered: their advantages and drawbacks are analyzed. The significant attention is given to electroluminescent methods of the DT control of optoelectronic devices with potential barriers during their operation. The advantages of these methods are considered in comparison with known in the reference literature.


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T.D. Melnichenko, V.M. Rizak, T.M. Melnichenko, V.I. Fedelesh

The Parameters of Free Volume Theory in Ge-As(Sb)-S and Cd-As Semiconductor Glasses

Uzhgorod National University,
54, Voloshin Str., Uzhgorod, 88015, Ukraine, E-mail:ipk@univ.uzhgorod.ua

By the data of elastic constants the parameters of fluctuation free volume theory (maximum internal pressure pim, volume of fluctuation micro cavity Vh, share of fluctuation free volume fg, microcavity formation energy Eh) for Ge-As(Sb)-S and Cd-As glasses. Dependence of elastic constants and parameters of fluctuation free volume theory on the interaction force non-linearity between kinetic units and value of mean coordination number Z in researched glasses are considered. We notify on the connection between the parameters of fluctuation free volume theory and characteristics of Boson maximum in Raman spectra.


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S.N. Grigorov, V.M. Kosevich, S.M. Kosmachev, A.V. Taran

Crystallization of the Amorphous Indium Selenide Films during Annealing

National Technical University, Kharkiv Polytechnical institute
21, Frunze Str., Kharkiv, 61002, Ukraine, (0572) 400-092, E-mail:sngrigorov@kpi.kharkov.ua

The article presents the TEM investigation of phase composition and structure of indium selenide thin films, deposited onto a glass and KCl surfaces at room temperature. Crystallization of amorphous films and phase transformations in such films took place during annealing in vacuum chamber at different temperatures as well as during annealing in situ.
Keywords: cooper chalkopyrite CuInSe2(CIS), indium selenide (In2Se3), solar cell, layer, composition, evaporation, electron microscopy, film structure.


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M.A. Glauberman, O.A. Kulinich, V.V. Yegorov, N.A. Kanischeva, V.V. Kozel

An Influence of Structure Defects of Presurface Silicon on Transduction Properties of Inversion-Injection Magnetosensitive Structure

Training, Scientific-Investigation and Production Centre,
association with the Odessas Mechnikov National University
4, M. Govorova Str., Odesa, 65063, Ukraine, E-mail:mag@farlep.net

The influence of structural imperfections, the impurity composition and the doping in homogeneity on the parameters responsible for sensitivity of the inversion-injection magnetosensitive structure has been found out with the aid of modern research methods.
The plates of initial monocrystalline and epitaxial silicon and oxidised silicon structures have been investigated.
Oxygen and carbon have been found out to be the basic impurities in the initial and oxidised silicon. Besides, oxygen demonstrates electrical activity and influences on the parameters of the structural defects, on which the charge carrier mobility and the threshold voltage are dependent.


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R.K. Savkina1, O.B. Smirnov1, S.O. Yuryev2

About Correlation between Sonic-Stimulated Effect and Structural Perfection of CdxHg1-xTe Alloys

1V. Lashkaryov institute of Semiconductor Physics NAS of Ukraine,
Kyiv, E-mail:tenet@alfa.semicond.kiev.ua 2National University Lvivska Politechnika, Lviv


Sonic-stimulated change of the electron concentration and Raman scattering intensity in n-CdxHg1-xTe alloys was investigated. It was determined that the value of such effects grows at increasing of dislocations and low-angle boundaries density in crystal.


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N.P. Klochko1, N.D.Volkova2, G.I. Kopach1,V.I. Shkaleto1

Investigation f Cadmium Sulfide Buffer Layer Influence n Properties f Mo/CuInSe2/CdS System

1National Technical University (KhPI),
21, Frunze Str., 61002 Kharkiv, Ukraine
2National Aerospace University (KhAI),
17, Chkalov Str., 61070, Kharkiv, Ukraine
fax: 00-38-0572-400-601, E-mail:kopach@kpi.kharkov.ua

As have been shown by means of investigation of chemical bath deposited cadmium sulfide (CdS) layer influence on structure and electrical properties of Mo/CIS/CdS system in which copper indium diselenide (CIS) film played a role of base layer in photovoltaic device was obtained by electrochemical deposition, under normal temperatures CdS fulfilled functions of a chemical buffer, that protected base layer from atmosphere. However, after Mo/CIS/CdS annealing in argon at 400oC and ever at 300oC on an air the protective properties of CdS lost that was experimentally discovered as a destruction of p-n-junction inserted inside


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L.S. Monastyrskyy, A.M. Broda, O.I. Melnyk

Influencing an Impulsive Action on Dynamics of Temperature Fields at the Superlattice of Porous Silicon

Lviv Ivan Franko National University,
50, Drahomanov Str., Lviv, 79005, Ukraine, E-mail:monastyr@wups.lviv.ua

The pulsing distribution of heat in classical superlattices of porous silicon is explored. The implicit numerical method calculates temperature profiles created by activity pulsing laser and electron beams in superlattices. The opportunity of effective application of heat-insulating properties of porous silicon and usages of temperature profiles for investigation a nonlinear thermostimulated diffusion in superlattice objects is shown.


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A.I. Nesterenko

The Consecutive Appearance Phase Influence in Kinetic Qrowth Interphase Boundary in a Multiphase Diffusion Layer

Ukrainian State Chemical-Technoloqical University,
av. Gagarin, 8, Dnipropetrovck, 49005, E-mail:ugxtu@dicht.dp.ua

The task about structure and composition evolution of multiphase diffusion layer with takinq into account of the layer new phases consecutive appearance has been solved. In the ranqe covered the exchanqe process on the metal outer surface is the rate-determininq factor. This process brinq to the violation of the parabolic qrowth phases law. The phases qrowth kinetic analysis has been performed.
The results of computer simulation of the nitroqen diffusion in an iron have a qood correspondence with experimental data.


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D.M. Freik, V.V. Prpkopiv, U.. Pysklynetsj, M.I. Beley

Donor and Acceptor Influence of Thallium on CdTe:Tl Crystals

Vasyl Stefanyk Prekarpathian University,
57, Shevchenko Str., Ivano-Frankivsk, 76000, Ukraine, E-mail:freik@pu.if.ua

At the both of donor influence of thallium on CdTe at the low carrier concentration (~1016cm-3) and acceptor influence of thallium at the high concentration (~1017cm-3) the experimental dependence of nx us annealing temperature and partial pressure of cadmium vapor are explain. The dependence of defect concentration and realization of n-p-junction on CdTe:Tl crystals from technology factors are calculation.


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Y.M. Bogdanovski, V.M. Myshchyshin

Masstransfer in System of Boron Solid Planar Sources and Silicon Plates with 300 mm Diameters

National University Lvivska Polytechnica,
12, Bandery Str., Lviv, 79013, Ukraine

The mechanism of transfer in inertial environment of nitrogen is offered for gaseous 23 from the solid planar sources (SPS) of boron to the plates of silicon with such diameters as 300 mm and more. These SPS of boron were on the basis of alumina-boron-silicone substances (ABSS). In the temperature range 85011000C distribution of concentrations of 23 between SPS and plate of silicon was calculated as well as 23 diffusion coefficients were found in nitrogen. It was shown that at SPS use B2O3 concentration near the surface of silicon plate exceeds 90% of the 23 concentration on the surface of SPS after 60 seconds. This value is substantially less than duration of doping processing of silicon plate with boron.


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Y.S. Budjak

The Screening Effect by Current Carriers of Admixture Atoms and These Influences on Crystal Properties

National University Lvivska Politechnika,
12, Bandera Str., Lviv-13,Ukraine, 79013

It is shown the influence of screening effect on the Zeebecs coefficient and carrier concentration in crystals. The condition of delocalization of valence electrons of admixture atoms was found out in the conditions of weak interaction between the ionized admixtures that condition of origin of admixture energy band.


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B.. Ostafiychuk, .. Budzulyak, .. Gasyuk, .. ss*

Element Consist Specific of n4Se3 Surface Monocrystalls, by Laser Treatment

Vasyl Stefanyk Prekarpathian University,
57, Shevchenko Str., Ivano-Frankivsk, 76025, Ukraine,
*Institute of Material Science Problems NAS of Ukraine, Chernivtsy branch

By Auger-electronic spectroscopy the element composition of surface of n4Se3 monocrystalline is explored in dependence on the value of current of sounding electronic bunch and density of energy of impulsive laser irradiation. The optimum modes of operations Auger-micro-sonde, which the real data about element composition of surface of samples n4Se3 without its damage were got at, were set (current of probe 0,3-0,4 mA, diameter of probe 200 mm, the acceleration tension 10 kV, increase no more 70). It is shown, that at density of energy of laser radiation desorbtion of both the oxygen and carbon atoms from the surface of n4Se3 samples passes in a range 2-6 J/cm2, and at density of energy of radiation 8-10 J/cm2 such desorbtion is carried out from the unexposed part to the rays of samples on border with the exposed area to the rays.


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.V. uchuk1,3, A. Piotrowska1, K. Golaszewska1, R. Jakiela2, .S.  Lytvyn3, V.P. Kladko3, .. rchovyi3, N.V. Osadcha3

The Study of Thermal Stability of Ta-Si Films on the GaAs Substrate

1Institute of Electron Technology,
Al. Lotnikow 32/46, 02-668 Warsaw, Poland, Tel. (0-22) 5487875,
2Institute of Physics, PAS,
Al. Lotnikow 32/46, 02-668 Warsaw, Poland,
3V. Lashkaryov Institute of Semiconductor Physics of NAS of Ukraine,
41, pr. Nauki, Kyiv, 03028, Ukraine, Tel: (044) 265-59-40, E-mail:olytvyn@isp.kiev.ua

In the paper we studied the thermal stability and matters of thermal degradation of the contacts Ta-Si/GaAs deposited by r.f. magnetron sputtering from Ta5Si3 target. In order to characterize the thermal stability, the Ta-Si contacts were annealed at 400-800oC for 5 min in Ar ambient. Before and after rapid thermal annealing, the samples were characterized by a set of supplementary methods including secondary ion mass spectrometry, Rutherford backscattering spectrometry, X-ray diffraction, atomic force microscopy and sheet resistance measurements.
As deposited Ta-Si films were amorphous and preserved this amorphous nature up to 600oC. Annealing at the temperatures above 600o causes a film crystallisation and appearing of a tantalum silicides which assists to Ga and As atoms diffusion and interface broadening. Thus, the films could be used as ohmic or barrier contacts, as well as antidiffusion layers up to 600oC. The films must be improved for applications at higher temperatures.


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A.V. Kramar, N.K. Kramar, S.V. Melnychuk, P.I. Melnyk1

Intracentre Absorption Spectra by the 3d-group Impurity Ions in PbI2

Chernivtsi National University
2, Kotsubynsky Str., Chernivtsi, 58012, Ukraine, -mail:kramar@itf.cv.ukrtel.net
1Precarpatian University
57, Shevchenko Str., Ivano-Frankivsk, 76025, Ukraine

The frequencies of internal transitions in impurities in layered semiconductor crystal PbI2 were calculated using the crystal field theory methods. Possibility of configurations mixing is taken into account.


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Y.P. Saliy, I.M. Freik

The Electrotechnical Model of Electric Conductivity of PbTe Thin Polycrystalline Films

Precarpatian University
57, Shevchenko Str., Ivano-Frankivsk, 76025, Ukraine

A new model of the size effect description in thin polycrystalline semiconductor films was proposed. It is assumed that a polycrystalline film consists of the grains which are formed two regions with different electrophysical properties. They regions are the corn and surface. The development of this model allowed us to separate of the share of both one grain and grain surface electronscattering on size effect of resistivity of PbTe polycrystalline films.


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G.P. Chuiko, N.M. Chuiko, O.V. Dvornik

Densities of States and Effective Masses within Generalized Kildal Model (Cd3P2 AS an Example)

Kherson State Technical University, Department of Cybernetics, Laboratory of solid state theory,
Berislavske shosse, 24, 73008, Kherson, Ukraine,
phone: +380-0552-326922,E-mail:olga_dvortnik@mail.ru

The dependences of densities of states and effective masses on energy within the generalized Kildals model have been formalized first time. It was performed for crystals with symmetry centre and for actual bands especially for the s-type conductivity band as well as for three p-type valence bands. The closed algorithms and the expressions for the calculations of mentioned above dependences have been obtained. Only the parameters of generalized Kildal-model contain in these expressions. The numerical calculations of the densities of states for the cadmium phosphide (Cd3P2) as a promising laser material and the calculations of the values of the electrons effective masses as well as of the heavy, light and spin-spllited holes (m*/m0 = 0.048 and 0.664, 0.155, 0.169 respectively) has been performed at first time. The calculated energy dependence of electrons effective mass is well agreed with experimental examinations.


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V.V. Khomyak, V.O. Grechko, S.B. Bilichuk, L.M. Mazur

Preparation and Characterization of CdO Thin Films Deposited by Reactive Magnetron Sputtering

Chernivtsi National University named after Yu. Fedcovych,
2, Kotsybinskiy Str., Chernivtsi, 58012, Ukraine, tel. 584873, E-mail:semicon@chnu.cv.ua

The paper describes the preparation of cadmium oxide thin films produced by reactive magnetron sputtering onto heated and unheated substrates. The electrical and optical properties of the deposited films and the effect both of substrate temperature and annealing temperature on the different physical properties of the films were investigated. Highly conducting, polycrystalline CdO thin films with good transmittances were prepared by controlling the conditions of sputtering, the deposition temperature and substrate temperature. These layers can be used for effective photovoltaic devices.


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I.V. Kalytchuk, V.M. Klanichka

Charge Carriers Scattering on n-PbS Films

Vasyl Stefanyk Prekarpathian University, Physical-Chemical Institute,
57, Shevchenko Str., Ivano-Frankivsk, 76000, E-mail:pcss@mail.ru,

The analyses of Hall mobility dependence from thickness on epitaxial layers n-PbS, growth on (111) BaF2 monocrystalline by hot-wall-method are provide. It is made the computation of mobility of charge carriers on both the surface films scattering and dislocation uncorrected.


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I.M. Smolensky

Technical and Ecological Aspects of the Rigid Polymer Materials Photodegradation
(Review)
Part I


Ivano-Frankivsk National Technical Oil and Gas University,
15, Karpatska St., Ivano-Frankivsk 19, Ukraine, 76019, E-mail:ismolensky@ifdtung.if.ua

It is the first time when on the basis of the existing oxidation and destructive processes a multimodule concept of UF-radiation atmosphere resistance was developed, as well as general model of photooxidation degradation (POD) of the polymer materials (PM) within the ecological material study context with a complex union of all stages of ecologichemical and photophysical processes of POD. On the example of polyamids (PA) within the context of modern green photochemistry, structural, functional block-schemes of the impact technological monitoring of production and exploitation processes were suggested alongside with the methods of the directed photoutilization of specific PM; there were also developed speedy methods of kinetic control (WO2, SEk, Yt) they can be applied in the mode of temporal diffusive-kinetic (gi , ELAr , ELAk) or physical-mechanical (p, E, M) and ingredient-color (KCol, MLRp) criteria of POD.


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P. Fochuk, O. Panchuk, L. Shcherbak

Dominant Point Defect Nature Specification in CdTe Crystals: Cd Saturation Region

Chernivtsi National University, Chemical Department,
2, Kotziubinskoho Str., Chernivtsi, 58012, Ukraine
phone: +380 (372) 58-47-45, E-mail:fochuk@chnu.cv.ua

High-temperature Hall effect measurements for undoped CdTe grown by Bridgman method and (Traveling Heater Method) in temperature range of 600-900o were carried out. It was established that Cdi2+ is the dominant intrinsic donor defect with enthalpy formation of ~2.1 eV. The defect structure modeling for d = 1 atm have demonstrated satisfactory agreement with experiment.


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.. Aksimentyeva, .. nplnyk, .. Ukrainets, .Ya. Grytsiv, G.V. Martyniuk

Anisotropy of Conductivity and Percolation Phenomena in Film Composites of Conjugated Polyaminoarenes and Polyvinylalcohol

Ivan Franko Lviv National University
50, Dragomanov Str., Lviv, 79005, Ukraine

Electrical properties of polyvinylalcohol (PVA) composites with conducting polymers (polyaniline, polytoluidine, polymethoxyaniline), obtained by polymerization of aminoarenes in PVA matrix were studied. It has been shown the composite conductivity dependence on concentration exhibits a percolation character with threshold in the range 1.6-2.6 %. In the studied composites the significant anisotropy of conductivity was manifested, a degree of anisotropy increases with increasing of conducting polymer content. On the base of temperature dependence of conductivity it is shown the effective activation energy of charge transport is similar to calculated for polyaminoerene and is 0.470.01 eV..


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D. Freik, . Dmytriv, P. Zukowski*, L. Mezhylovska

Atomic Defects and Physical-Chemical Properties of Cd1-xMnxTe Solid Solution with Oxygen at the Annealing

Vasyl Stefanyk Prekarpathian University,
201, Galytska Str., Ivano-Frankivsk, 76000, Ukraine, E-mail:freik@pu.if.ua
*Lyubli Technical University, 20-618 Lyublin, Poland
E-mail:mario@elektron.pol.lublin.pl

It is researches of defect subsystem on Cd1-xMnxTe solid solution with non-control oxygen impurity by crystal-quazichemical method. The type of conductivity of solid solution at the annealing on cadmium and tellurium vapor is got.


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A.T. Kolodyazny, L.A. Frolova, N.P. Makarchenko, E.M. Prokopenko

Research of Alkaline Hydrolysis of Cobaltium Chloride

Ukrainian Chemical Technology University,
8, Gagarina Av., Dnipropetrovsk, 49005, Ukraine,
tel.: (0562) 47-46-70, fax: (0562) 47-33-16, E-mail:ugxtu@dicht.dnepropetrovsk.ua

The system Cl2-NaOH-2O by methods of residual concentration of ananaev, potentiometry, measurement of optical density is investigated. Is found out, that the reaction of interaction between Cl2 and NaOH proceeds in two stages with formation at first of basic salt and then hydroxide. The deposit Co(OH)2 does not grasp alkali from a solution. In solutions with concentration 0.545 moll and 0.1195 moll the basic salt of structure (OH)1,8Cl0,2, (<0.1 moll) (OH)3,8Cl0,05 are formed.


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V.M. Boychuk

Physical-Chemical Properties and Atomic Defects on Solid Solution PbTe-TlTe

Physical-Chemical Institute at the Vasyl Stefanyk Prekarpation University,
201, Galytska Str., Ivano-Frankivsk, 76000, Ukraine

The models and defect formation mechanisms on solid solutions PbTe-TlTe are proposed. It is show, that on any charge states of thallium ions realization at the lead vacancy substitution or completion of cationic sublattice on PbTe the donor or acceptor action to show up, accordingly. At the simultaneously mechanisms, as substitution and intercalation of thallium on basic matrix the increase of electron concentration is prevails.


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H.A. Sirenko, L.Ya. Midak

The Influence of Solid Oil and Technological Factors on Antifriction and other Mechanical Properties of Composite Material Based on Polytetrafluoretylene and Carbon Fiber

Vasyl Stefanyk Precarpathian University,
57, Shevchenko Str., Ivano-Frankivsk, 76000, Ukraine

The influence of concentration of solid oil and technological factors (concentration of special carbon fiber and time of its previous pounding) in invariable time of mixing of composition on antifriction and other mechanical properties of composite materials based on polytetrafluoretylene and carbon fiber is researched using methods of mathematics planning of experiment and search of optimal decisions.


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D.. Freik, R.Ja. Mykhajljonka, V.M. Klanichka

The Measuring Methods of Heat Conductivity on Semiconductor Materials
(Review)


Physial-Chemical Institute at the Vasyl Stefanyk Prekarpathian University
Shevchenko str., 57, Ivano-Frankivsk, 76000, Ukraine, E-mail: freik@pu.if.ua

The basic methods of measuring of the heat conductivity of solids and thin films and construction of devices for these methods are shown. The theoretical and empiric formulas for calculation of heat conductivity of simple and difficult materials are resulted by any methods. The exactness of measuring is appraised for each of methods and analizing the reasons, which errors at measuring are through.


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T. Boczar, S. Wolny

Determining the Influence of the Factors that could Disturb Repeatability of the Measurement Results of the AE Pulses Generated by PDs

Technical University of Opole, Poland

This paper presents detailed results of statistical analyses carried out using parametric tests of goodness of fit referring to determining the influence of placing an insulation layer between the electrodes of the spark gap modeling PDs of the multipoint-plane type on the repeatability of the results obtained.
Keywords: insulation layer, spark gap.


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I.S. Pogrebova, T.N. Pylypenko, R.I. Jurchenko

Influence of Quaternary Salts Pyridine on Plasticity and Corrosion-Electrochemical Behavior of Mild Steel in Solution of a Sulfuric Acid

National Technical University of Ukraine KPI
Peremogy Avenue 37, Kyiv, 03056, Ukraine

Corrosion-mechanical destruction of steel 08 KP in 3 molel-1 solution H2SO4 at the presence of some quaternary salts pyridine is investigated. The interrelation between protective properties of the investigated connections and their influence on change of plasticity of steel is revealed at its etching in a solution of a sulfuric acid. Connections which effectively inhibition corrosion-mechanical destruction of steel are revealed and assumptions of the mechanism of their protective action are stated.


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V.F. Loskutov, .. Bobina, .V. Loskutova

Microporosity of the Niobium-Chrome Carbide Coverage

National Technical University "PI" of Ukraine,
37, Peremogy Av., Kiyv, E-mail:ulvasha@zeos.net

The results of researches of different factors influence on porosity of carbide coverage on the basis of carbide of niobium Nb. It is shown, that on account of their alloying by chrome in work are presented.


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.. Nikolenko, .V. Kindrachuk, E.. Sysun, .. Kornienko

Analysis of Technology of Growing Shallow of Fragile Materials

Institute of Radiophysics and Electronics, named by .Y. Usikov NAS of Ukraine
12, Acad. Proskura Str., Kharkov, 61085, Ukraine

Possibilities of application of methods of the mathematical planning of experiments to the decision of tasks of analizes of growing shallow of fragile materials technologies are explored. The recommendations from determination of great numbers of factors and review functions and also methods of their appropriate are presented. The present method is applied to researches of process of growing shallow of Pb-B-Si glass.


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