R.I. Zapukhlyak1, T.O. Parashchuk1, V.M. Chobanyuk1, N.D. Freik1, P.M. Fochuk2
Thermodynamics Properties of Sphalerite Crystal of Zinc Telluride: Quantum-Chemical Calculation (Review)
1Vasyl Stefanyk PreCarpathian National University 57, Shevchenko Str., 76018, Ivano-Frankivsk, Ukraine, E-mail:firstname.lastname@example.org
2Yu. Fedkovych Chernivtsi National University
Based on the analysis of the crystal and electronic structure of cubic β-ZnTe cluster models for calculation of the geometric and thermodynamic parameters have been made. Techniques of incorporation of boundary conditions for the two cluster models cubic phase ZnTe have been proposed. These equilibrium phase diagrams of binary systems Zn-Te and ZnTe have been shown. Based on the results of ab initio quantum-chemical calculations of the crystal structure of molecular clusters the temperature dependence of the energy ΔE and enthalpy ΔH of formation, Gibbs potential ΔG, heat capacity at constant pressure CP and volume CV, entropy ΔS have been defined. Computer calculations of thermodynamic parameters were performed using the density functional theory DFT with valence hybrid basics B3LYP. Also, in the analytical expressions are obtained temperature dependences presented thermodynamic parameters have been approximated by a quantum-chemical calculation points using mathematical package Maple 14.
Keywords: cluster model, quantum chemistry, zinc telluride, thermodynamic parameters.
O.V. Balaban, B.A. Lukiyanets
Mechanical Effect of Ultrasound in Microscopic Object with Nanoscale Pores
Lviv Polytechnic National University, Kotlyarevsky Str. 1, Lviv, 79013, Ukraine, e-mail:email@example.com
Theoretical study of ultrasonic treatment of a microscopic object with nanoscale pores is presented. It is shown that additional pressure created by ultrasonic waves inside the pore is much higher than such pressure on the object. Hence area of the pore is the least mechanically resistant under ultrasonic treatment of the object.
Keywords: ultrasound, nanopore.
V. Holovatsky, I. Bernik
Oscillator Strengths of Intraband Transitions in Spherical Quantum Dot GaAs/AlxGa1-xAs/GaAs/AlxGa1-xAs with Central Donor Impurity
Chernivtsi National University, Chernivtsi, Kotsubynsky str., 2, 58012, tel. 80372244816, e-mail:firstname.lastname@example.org
The distribution of electron densities in multilayered quantum dot GaAs/AlxGa1-xAs/ GaAs/AlxGa1-xAs with central hydrogen-like impurity is calculated using energies and wave functions of the electron in the nanosystem obtained in the approximation of effective masses and rectangular potential barriers. It is also investigated the influence of the impurity on oscillator strengths of intrraband transitions. The dependencies of 1s-1p and 1s-2p quantum transitions are obtained as functions of geometrical parameters of the QD. It is shown that the oscillator strengths of different quantum transition can reach a maximum values in their own ranges of nanosystem sizes. The presence of donor impurity essentially affects the distribution of electron densities in nanosystem and oscillator strengthes of quantum transitions.
Keywords: multilayered quantum dot, donor impurity, intraband transitions, oscillator strength.
The Role of Nucleus in First-Order Spin-Reorientation Phase Transition
Donetsk National University, 24 Universitetskaya str., Donetsk 83001, Ukraine
The mechanism of spin-reorientation phase transition (SRPT) in ferrite-garnet films has been studied. Changes in structure of domain boundaries during phase transition have been investigated. Domain structure (DS) models appropriate for the experiment are proposed. It has been shown that the phase transition through nucleation in the domain boundary induces the first-order phase transition from axial to angular phase. The SRPT mechanism does not depend on the value of ratio between anisotropy constants.
Keywords: domain structure, domain boundary, anisotropy, spin-reorientation phase transition.
O.V. Pugantseva, V.M. Kramar
Temperature Dependences Of The Electrons Ground State Energy In E-MAA/PBI2/E-MAA NANOFILMS
Yuriy Fed’kovych Chernivtsi National University, 2 Kotsiubynskogo Str., 58012 Chernivtsi, Ukraine; e-mail:email@example.com
The method of theoretical studying of the temperature dependence of the electron energy in a flat semiconductor nanofilm, which consists of layered semiconductor inserted into an organic dielectric medium, is proposed. This method based on the effective mass approximation for electronic and dielectric continuum model – for the phonon system. Specific calculations are made for the example of lead iodide as well material and ethylene-methacrylic acid copolymer (E-MAA) – as a barrier. It is shown that heating of nanosystem over 50 – 75 K causes a shift of the electrons ground state to the side of lower energies. The shift value is a monotonically increasing temperature function. The growth velocity of this function depends on the nanofilm thickness.
Keywords: nanoheterostructure, quantum well, nanofilm, electron, energy, layered semiconductor, lead iodide.
A.S. Shirinyan1, Y.S. Bilogorodskyy2, V.A. Makara1,3
Size-Dependent Loop of Two-Phase States of the Isolated Cu-Ni Nanoparticle
1“Physical-chemical materials science” center of Kiev Taras Shevchenko National University and National Academy of Sciences of Ukraine, Physics Faculty,
Glushkova avenue 2, 03680, Kyiv, Ukraine
2Cherkasy regional ecological-naturalistic center, Minor Academy of Sciences, Smelianska street, 132, 18029, Cherkasy, Ukraine 3Department of metals physics, Physics Faculty of Kiev Taras Shevchenko National University, Physics Faculty, Glushkova avenue 2, 03680, Kyiv, Ukraine
It is discussed the general thermodynamic reasons about a phase diagram for multicomponent nanosystems in which the phase transformation liquid-solid type takes place with concentration depletion. It is calculated and constructed the size-dependent loop of intermediate two-phase states for the crystallization of the isolated nanosized Cu-Ni particle of 30nm radius. The change of critical points of phase transformation is confirmed for a nanoparticle.
Keywords: thermodynamic approach, nanoparticle Cu-Ni, crystallization, phase equilibrium curves, size effect, depletion, two-phase loop.
I.O Arsenyuk1, Ts.A. Kryskov1, L.Yo. Mezhylovska2, D.M. Freik2
Synthesis and Thermoelectric Properties of Bismuth Doped of Stanum Telluride
1Kamyanets-Podilsky Nationality University, Ogienko Str. 61, Kamyanets-Podilskiy, 32300, Ukrainе, E-mail:firstname.lastname@example.org
2Vasyl Stefanyk. Precarpathian National University, Shevchenko Str.57, Ivano-Frankivsk, 76025, Ukraine, E-mail:email@example.com
In the article describing the technology of synthesis of semiconductors AIVBVI. The results of the study of thermoelectric properties SnTe and SnTe:Bi.
B.K. Ostafiychuk, V.S. Bushkova, А.V. Kopayev, I.P. Yaremiy
X-ray and Electron Microscopic Studies of Diamagnetic Substituted Ferrite Systems
Vasyl Stefanyk PreCarpathian National University 57, Shevchenko Str., Ivano-Frankivsk, 76025, Ukraine, E-mail:firstname.lastname@example.org
In this paper the magnesium-zinc and nickel-aluminum ferrites were synthesized using the method of sol-gel with participation of autocombustion process. By means of X-ray investigation it was determined the phase composition and structural features of the diamagnetic substituted ferrite systems. It was shown that the resulting complex oxide powders are agglomerated and consist of several nanoparticles with an average size of 20-35 nm. It was found cooling mode of particles after passing of autocombustion process. Keywords: sol-gel method, ferrite, spinel, cationic distribution.
R.R. Levitskii1, I.R. Zachek2, A.S. Vdovych1
Dielectric Properties of Monoclinic RbD2PO4 Type Ferroelectrics
1Institute for Condensed Matter Physics of the National Academy of Sciences of Ukraine, 1 Svientsitskii Street, 79011, Lviv, Ukraine
2 Lviv Polytechnic National University, 12 Bandery Street, 79013, Lviv, Ukraine
We proposed modified proton ordering model for quasi-one-dimensional monoclinic RbD2PO4, that takes into account linear over strains εi and ε5 contributions to the proton subsystem energy. Within the framework of the model, using the two-particle cluster approximation we obtain a system of equations for the strains εi and ε5 and for the order parameter. Using these equations we calculate the static dielectric permittivity of the crystal. The dynamic dielectric permittivity of the crystal is calculated within the D.N.Zubarev nonequilibrium statistical operator method. The available experimental data for static and dynamic permittivities, is described.
Keywords: ferroelectrics, cluster approximation, heat capacity, dielectric permittivity, piezoelectric moduli, elastic constant.
P.V. Galiy1, О.Ya. Tuziak2, O.V. Tsvetkova1, I.R. Yarovets1
Dynamics of Surface Stoichiometry Change of CsI Crystals Under the Condensed Energy Flux: Role of Thermal and Electron Excitations
Ivan Franko Lviv National University,
2Physics faculty, 50 Drahomanov Str., Lviv, 79005, E-mail:email@example.com
Dynamics of CsI and KCl crystals surface stoichiometry change under electron and neodymium IR-laser irradiation was investigated. It was determined, that at low temperatures of irradiated surfaces change of CsI and KCl surfaces stoichiometry is defined mainly by electron mechanisms of halogen sputtering, thus both surfaces are enriched with metallic component. When at the crystals surfaces are achieved high close to melting temperatures, surfaces stoichiometry change is defined by the rates of component’s diffusion to the surface and evaporation, in that case CsI surface is enriched with halogen, while KCl surface – with metal. These processes are quasi-periodical and dependent on fluence and irradiation dose.
Keywords: laser and electron irradiation, auger-electron spectroscopy, surface stoichiometry of alkali halides crystals, surface defects.
S.G. Orlovskaya, M.S. Shkoropado, F.F. Karimova
Peculiarities of Tungsten Oxide Fibers Formation and Growth
Odessa national I.I. Mechnikov’s University Odessa, Ukraine, Dvoryanskaya str. 2, 65082, e-mail:firstname.lastname@example.org
Promising applications of tungsten oxides stimulate wide studies of tungsten high temperature oxidation. Oxide microcrystals are of particular interest due to their high specific surface and unique physical properties. Formation and growth of tungsten oxide fibers and “bushes” are studied experimentally by “hot filament” method. Tungsten filament is heated electrically in air, the value of an electric current is matched to provide quasi-stationary regime of oxidation. At the beginning a continuous oxide layer is formed on the metal surface. When filament temperature exceeds 900 K, separate needles appear. They grow quickly, branch out and attain a height of 250 microns in ten minutes. So their growth rate is about 0.5 mcm/s. Obtained oxides structures were studied by SEM. A significant amount of carbon is found at the base of the needles and bushes. The carbon particles remain after wire-drawing with aquadag on the filament surface. In case a filament is cleaned carefully from carbon before oxidation no fibers are formed on the oxidized surface. Thus we conclude that primary crystallites are formed on carbon particles as a result of carbothermal reduction of tungsten trioxide molecules adsorbed from a gas and the following oxidation of tungsten and tungsten suboxides. The relatively high growth rate of crystals in our experimental conditions may be explained by mechanism “grain-by-grain buildup” Keywords: high temperature oxidation, tungsten oxides, oxide microcrystals, carbon.
O.M. Bordun, V.G. Bihday, I.Yo. Kukharskyy, Z.V. Stasyuk
Photoelectrical Properties of Pure and Activated Mn2+ Thin Films of Zinc Gallate
Ivan Franko Lviv National University, 50, Dragomanov Str., Lviv, 79005, Ukraine, tel. (0322) 239-714, e-mail:email@example.com
Cathodoluminescent and photoelectric properties of ZnGa2O4 and ZnGa2O4:Mn thin films deposited by high-frequency ion-plasma sputtering were investigated depending on conditions and atmosphere of heat treatment. It was found that the annealing at 750С in the reducing atmosphere leads to an increase of the luminescence intensity and the electrical conductivity of the films. ZnGa2O4:Mn thin films conductivity increasing after the annealing in the reducing atmosphere is associated with the creation of a high concentration of oxygen vacancies and interstitial cation defects, which leads to the appearance of n-type conductivity.
D.M. Freik1, E.A. Achimova2, Ts.A. Kryskov3, T.S. Lyuba3, A.Yu. Meshalkin2, S.V. Optasyuk3, O.M. Rachkovsky3, B.I. Tsykanyuk 3
The Influence of Impurities of Sb on Transmission Spectra of PbTe Thin Films in The Infrared Wavelength Range
1Vasyl Stefanyk PreCarpathian National University, 57, Shevchenko str., Ivano-Frankivsk, 76025, Ukraine, e-mail:firstname.lastname@example.org
2Institute of Applied Physics AS of Moldova, Academiei Str. 5, Chisinau, MD-2028, Republic of Moldova, e-mail:email@example.com
3Ivan Ohienko Kamyanets-Podilsky National University, 61, Ogienko str., Kamyanets-Podilsky, 32300, Ukraine, e-mail: firstname.lastname@example.org
The technology of synthesis of bulk samples and deposition of thin films of stoichiometric lead telluride and with antimony impurities in different concentrations are described. The optical properties of the films were recearch and on the basis of the received graphical dependencies were calculated value of the band gap by the method of Tauc
Keywords: lead telluride, thin films, optical properties, energy gap.
D.V. Myroniuk1, G.V. Lashkarev1, A.S. Romaniuk3, V.Y. Lazorenko1, I.I. Shtepliuk1, V.A. Skuratov2, I.I. Timofeeva1, V.V. Strelchuk3, O.F. Kolomys3, V.V. Khomyak4
Effect of Swift Heavy Ion Xe26+ on the Properties of ZnO Films Deposited on Silicon Substrates
1Frantsevich Institute for Problems of Materials Science of NAS of Ukraine, 3, Krzhizhanovsky str., 03680, Kyiv, Ukraine, e-mail:email@example.com
2Lashkaryov Institute of Semiconductor Physics of NAS of Ukraine, 41, pr.Nauki, 03028, Kyiv, Ukraine 3Joint Institute for Nuclear Research, 6, Joliot-Curie str., 141980, Dubna, Moscow region, Russia 4Fedkovych Chernivtsi National University, 2 Kotsubinsky str., 58012, Chernivtsi, Ukraine
Zinc oxide films were grown by direct current magnetron sputtering on the silicon substrates and irradiated by ions Xe26+ with energy 167 MeV and fluences of 1012 and 1013 cm-2. As-grown and irradiated samples were investigated by X-ray diffraction, photoluminescence and resonance Raman spectroscopy. It was found that radiation causes the appearance of defects, reducing the size of coherent scattering regions, reorientation of micrograins and the increase of the defect PL band.
Keywords: zinc oxide, ZnO, irradiation, swift heavy ions, point defects, recrystallization.
І.M. Fodchuk1, R.A. Zaplitnyy1, I.I. Gutsuliak1, І.P. Yaremiy2,
G.V. Savitskiy3, U.O.Tomyn2
Investigation of the Y2.95La0.05Fe5O12 Films Properties after Ion Implantation
1Yuriy Fedkovych Chernivtsi National University, Kotsubinskiy Srt. 2, 58012, Chernivtsi, Ukraine, firstname.lastname@example.org
2V.Stefanyk Prykarpatskyy University, Shevchenko Str. 57, 76025, Ivano-Frankivsk, Ukraine, email@example.com
3Institute for Applied Problems of Mechanics and Mathematics of NASU, Naukova Str. 3-b, 79601, Lviv, Ukraine, firstname.lastname@example.org
The structure changes in the surface layers of Y2.95La0.05Fe5O12 iron-yttrium garnets (YIG) after high-dose ion implantation by nitrogen ions were investigated by means of methods of high-resolution X-ray diffractometry.The course of structural changes in Y2.95La0.05Fe5O12 crystals caused by irradiation of nitrogen ions was established by selecting appropriate models of defective structure that contain several types of dominant microdefects and damaged surface layer distributed in specific way. It is shown that rearrangement of the crystal structure under the action of high-dose nitrogen ion implantation leads to decreasing of the FMR lines of Y2.95La0.05Fe5O12 epitaxial films. Keywords: iron-yttrium garnet, ferromagnetic resonance, epitaxial films, high-dose ion implantation.
The Density of Electron States of Nickel Silicide Amorphous Film
Frantsevich Institute for Problems of Materials Science of NASU, 3 Krzhyzhanovsky Str., Kiev, 03680, Ukraine, e-mail:email@example.com
The density of electron states of amorphous nickel silicide has been calculated. With this object definite equations were got based on theory N. Mott and E. Davis. Electron states at the top of valence band are conditioned by d electron of nickel, p electron of silicon, s electron of nickel.
D.M. Freik, B.S. Dzundza, Ya.S. Yavorskyy, O.B. Kostyuk, O.M. Matkivskiy
Surface Layers and Thermoelectric Properties of Thin Films of Solid Solutions PbTe-Bi2Te3
Vasyl Stefanyk PreCarpathian National University 57, Shevchenko Str., Ivano-Frankivsk, 76018, Ukraine, E-mail:firstname.lastname@example.org
Investigated thermoelectric properties of films based on solid solutions PbTe-Bi2Te3 for different composition which obtained by steam condensation in the open vacuum on sital and mica substrate. Based on a Petritz two-layer model defined electrical parameters of surface layers. The results are interpreted by processes of oxygen adsorption on the surface and its diffusion into the condensate.
Keywords: thin films, lead telluride, solid solutions, thermoelectric properties.
S.Yu. Vyshnevskyy1, I.M. Dmytruk1, A.P. Naumenko1, Yu.L. Briks2, Yu.L. Slominskii2
Interaction of Semiconductor Nanoparticles And Molecules of Polymethine Dye: Structural Transformation and Excitation Transfer
1Taras Shevchenko Kyiv NationalUniversity
2Instytut Organic Chemistry, Academy of Sciences of Ukraine
The results of the studying the interaction of cyanine dye molecules with CdSe nanoparticles (NPs) in aqua solution are presented. It is shown that depending on the dye concentration there are could be observed different manifestations of the interaction. Thus, in the presence of NPs for concentrations of dye 1×10¬5 М or more there is the appearance of intense absorption bands corresponding to the J-aggregates of dye. Instead, there is surface modification of NPs by dye molecules, at dye concentrations near 3×10¬6 М. Quenching of surface defect’s luminescence with simultaneous enhancement exciton band of the nanoparticles was observed. We found that the effect of surface passivation significantly weakened when the concentration of surfactant maintained constant at a dilution of base NP solution by water. Maintaining a constant concentration of L-cysteine at a dilution of colloidal solution of nanoparticles is necessary to prevent sticking and loss of sediment. However, NPs sticking and sediment loss was not observed even with a decrease of surfactant concentration from 1.6 to 0.08 mg/ml, in presence of the dye.
Keywords: semiconductor nanoparticles, polymethine dyes, J-aggregates, optical absorbtion, luminescence, surface passivation.
M.P. Semen’ko, M.I. Zakharenko, T.V. Kalnysh
Transport Properties of the Graphite - Metal Nanocomposites
Department of Physics, Taras Shevchenko university, 64, Volodymyrska st., 01601 Kyiv, Ukraine, e-mail:email@example.com
The temperature behavior of the resistance of the thermo exfoliated graphite (TEG) and cobalt-containing nanocomposites on its base have been investigated. It is shown that the electrical properties of these materials could be easy explained within the incipient localization model. The influence of the metal modifier on the electric transport has been also analyzed.
Keywords: thermoexfoliated graphite, cobalt, electric resistance, weak localization; nanocomposite.
D.М. Freik1, Ts.A. Krisko2, І.V. Gorichok1, T.S. Lyba1, L.V. Turovska1, O.S. Krunutcky1, O.M. Matkivsky1, І.P. Jaremij1, V.I. Makovushun1
Thermoelectric Properties and Defects Subsystems of Solid Solutions PbTe-Bi2Те3
1Vasyl Stefanyk Prekarpathian University, Shevchenko Str., 57, Ivano-Frankivsk, 76025, Ukraine, e-mail: firstname.lastname@example.org
2Kamyanets-Podilsky State University, Ogienko Str. 61, Kamyanets-Podilsk, 32300, Ukraine, е-mail: email@example.com
Studied the phase composition, structure and thermoelectric properties of solid solutions PbTe-Вi2Te3. Found that the increase of Вi2Te3 in solid solution leads to non-monotonic change of the lattice constant in a neighborhood with a minimum of 2 mоl. % and conductivity with a maximum at 1 mol. % Ві2Te3. Zeebek coefficient ratio decreases with increasing content of Bi2Te3 throughout the studied concentration range. When the content of Bi2Te3 ≥ 2 mol. % Of the most probable mechanism for the formation of a solid solution PbTe-Bi2Te3 is equivalent position of lead bismuth to form interstitial tellurium.
M.V. Moroz1, O.G. Mykolaychuk2, M.V. Prokhorenko3, V.M. Moroz1
Thermodynamic Properties of the GeSe, GeSe2, Ag8GeSe6 Compounds
1Department of physics National University of Water Management and Nature Resources Use, 11, Soborna Str., Rivne, 33000, e-mail:firstname.lastname@example.org
2Department for metal physics Ivan Franko National University, 8a, Kyryla and Mefodiya Str., Lviv, 79005 3Department of cartography and geospatial modeling Lviv Polytechnic National University, 12, Stepana Bandery Str, Lviv, 79013
In the galvanic elements C|Ag|Ag3GeS3I|B|C (C – current electrodes, В – heterophase alloys of the Ag–Ge–Se system, Ag3GeS3I – glassy alloy with pure ionic (Ag+) conductivity) synthesis Ag with heterophase alloys of system was exercise. Data on the emf temperature dependence of galvanic elements are used to calculate the values of thermodynamic function of GeSe, GeSe2, Ag8GeSe6 compounds.
M.P. Levkun1, G.Ya. Gurgula1, V.M. Bojchuk1, G.D. Mateik2
Crystall Chemistry Model of Points Defects and Dopeing Mechanisms Crystals ZnSe:Cr
1Vasyl Stefanyk PreCarpathian National University 57, Shevchenko Str., Ivano-Frankivsk, 76018, Ukraine, E-mail:email@example.com
2Ivano-Frankivsk National Technical University of Oil and Gas, 15, Carpathian Str., Ivano-Frankivsk, 76001, Ukraine
A crystal chemistry formula for doped n-ZnSe: Cr and p-ZnSe: Cr are proposed. The dependence of the dominant point defect concentration, the concentration of free carriers and the Hall concentration of charge carriers on the magnitude of the deviation from the stoichiometric composition (α, β) and the concentration of impurities Cr are defined.
Keywords: zinc selenide, point defects, Crystall chemistry formula, doping.
V.B. Boledzyuk1, V.M. Kaminskii1, Z.D. Kovalyuk1,
V.M. Sklyarchuk2, E.F. Sklyarchuk2
IR Absorption in Hydrogenated Layered GaSe Crystals
1Chernivtsi Department of the I.M. Frantsevich Institute for Problems of Materials Science of the National Academy of Sciences of Ukraine, Iryna Vilde St. 5, Chernivtsi, 58001, Ukraine; е-mail: firstname.lastname@example.org
2Chernivtsi National University, Kotsyubynsky St., 2, Chernivtsi, 58012, Ukraine
Infrared (IR) transmission spectra in the range 2.5 to 22.5 mm are measured at temperatures 77 and 300 K for initial and hydrogenated from gaseous phase GaSe crystals. It is shown that the observed absorption bands in initial GaSe crystals correspond to the second and third harmonics of IR-active phonons. For hydrogenated HXGaSe crystals we have established a shift of the energy position of the absorption bands, the appearance of a line of local vibrations in the hydrogen subsystem at T = 77 K as well as essentially increased transmission in the range λ < 12.5 mm.
Keywords: layered crystal, GaSe, hydrogenation, IR absorption.
М.М. Yatsyshyn, І.І. Demchyna, S.I. Mudry, R.Ya. Serkiz
Morphology of the Deposited Electrochemically in Potentiodynamic Mode on the Surface of Al87Ni8(REE)5 Amorphous Metallic Alloys Polyaniline Film
Ivan Franko National University of L’viv, Kyryla & Mefodiya St. 6, 79005 L’viv, Ukraine e-mail:email@example.com
The polyaniline films on the surface of amorphous metallic alloys of Al87Ni8(REE)5 content, namely Al87Ni8Y5, Al87Ni8Ce5, Al87Ni8Gd5 and Al87Ni8Dy5, were synthesized by the electrochemical oxidation of aniline in the potentiodynamic mode in the 0.5 М H2SO4 aqueous solution. The process of electrochemical aniline oxidation and redox transition of polyaniline are described. It is shown that the difference in the cyclic voltammogramms forms connected with nature of amorphizing additions, namely Y, Gd, Ce and Dy, which determines stability of surface oxide films on the surface of working electrodes. The analysis of the scanning electron microscopy images shown that the polyaniline film with extended surface forms on the contact side of the Al87Ni8(REE)5 electrodes. It was determined that morphology of polyaniline films depend also from the nature of amorphizing addition in the alloy. EDX spectra confirm polyaniline formation on the electrode surface and also presence of the sulfates of metals, which enter into the composition of working electrodes, in the polymeric films. Results of X-ray diffraction phase analysis indicated that the polymeric films on the surface of amorphous alloy electrodes forms the mixture of emeraldine base and emeraldine salt forms of the polyaniline.
Кeywords: aniline, electrochemical oxidation, potentiodynamic mode, polyaniline, polymeric films, morphology, structure, aluminium amorphous alloys.
L.S. Semko, S.V. Khutornyi, L.P. Storozhuk, L.S. Dzyubenko, P.P. Gorbyk
Formation of The Structure and Studying the Properties of Magnetically Operated Adsorbents Based on Magnetite and Silica with Higher Specific Surface Area
Chuiko Institute of Surface Chemistry, Ukrainian National Academy of Science, 17 General Naumov str., Kyiv 03164, Ukraine, firstname.lastname@example.org
It was developed the method of obtaining magnetically operated nanocomposites Fe3O4/SiO2 with high specific surface area. The structure, magnetic and adsorption properties of nanocomposites were investigated. It was shown that the use of triblock copolymer (poly (ethylene glycol)-block-poly (propylene glycol)-block-poly (ethylene glycol)) Pluronic-123 (P-123) as additives in the synthesis of composites led to a significant increase in their specific surface area (to 325 m2/g). For the output of the composite containing 0,5 g of SiO2 and P-123 in the range of 0,0007 to 0,7 g per 1 g of magnetite, the specific saturation magnetization (σs) is 4,02 - 5,67 mkTl•m3/kg, and Hc = 2,3 -7,62 kA/m. It was obtained adsorbents with composition Fe3O4/SiO2/DNA.
Keywords: magnetically operated nanocomposite, template synthesis, specific surface area, adsorbent.
О.А. Kapush, L.І. Trishchuk, V.М. Tomashyk, I.O. Mazarchuk, Z.F. Tomashyk,
A.O. Kuryk, S.I. Budzulyak
Influence of Conditions for Formation Peculiarities of CdS Nanoparticles in Colloidal Solutions
Institute of Semiconductors Physics of National Academy of Science of Ukraine, 41 Nauki Prospect, Kyiv 03028, Ukraine, e-mail:email@example.com
The physicochemical properties of nanosized systems based on CdS, obtaining by colloidal synthesis, have been investigated. Influence of conditions for the formation of the CdS nanoparticles in aqueous solutions has been also determined. It was shown that solvent and duration of synthesis significantly influences the colloidal synthesis of CdS nanoparticles. On the other hand, the photoluminescence characteristics of these solutions were studied in detail.
Keywords: cadmium sulphide, nanoparticles, colloidal solution, photoluminescence spectrum.
L.M. Soltys, H.O. Sirenko
The Influence of the Nano- and Microroughness of Surface of the Solid on the Physic-Chemical Contact Facts (Review)
Vasyl Stefanyk’ Precarpathian National University, 57, Shevchenko Str., Ivano-Frankivsk, 76025, Ukraine Tel. (0342) 77.64.15; (096) 813.93.53, e-mail:firstname.lastname@example.org
Article deals with the physico-chemical phenomena on microrough surfaces of the polymer composite and metal in dynamic contact. Review of sources which describe methods, parameters and mathematical and physical models of description of nanometrical and micrometrical roughness of surface of solid states.
Keywords: polymer composite, metal counterface, carbon fibers, roughness of surface, moments of spectral density, friction, intensity of wear, metallization, selective transport of copper.
Properties Renewable Electrolytic Alloys Obtained Programmatically
Dnepropetrovsk National University of Railway Transport Dnipropetrovsk, Ukraine E-mail:email@example.com, (067) 5659803
The results of study of the effect of pulse current on structure and physico-mechanical properties of electrolytic alloys of iron. It is shown that in their structure and properties significantly affect not only the concentration of the components, but also non-equilibrium crystallization conditions caused by pulsed mode of deposition.
Keywords: structure, electrolytic alloy microhardness, adhesion strength, surge current, rolling stock restoration parts, wear.
V.D. Fedoriv, N.V. Stashko, V.V. Moklyak
Kinetics of the Synthesis of Polycrystalline Yttrium Iron Garnet Based on Oxides, Obtained by Sol-Gel Method of Autocombustion
Vasyl Stefanyk PreCarpathian National University, 57, Shevchenko Str., Ivano-Frankivsk, 76000, Ukraine, E-mail:firstname.lastname@example.org
By sol-gel method from solutions with different pH were synthesized three systems to receive further Yttrium Iron Garnet. Using the derivatography methods we analyzed physico-chemical nature of thermal effects that accompany the process of heating of the systems. We found that on the synthesis process of the grenade significant effect has the initial pH of the solution components and atmosphere annealing. It was shown that the acid environment promotes the formation of single-phase garnet system.
O.V. Morushko, L.S. Yablon, I.M. Budzulyak, V.O. Kotsyubynsky, M.M. Kuzyshyn, B.K. Ostafiychuk, B.I Rachiy, O.M.Hemiy, Yavorskiy B.I.
Electrochemical Properties of Composite Laser Irradiated TiS2 / Nanoporous Carbon
Stefanyk Precarpathion National University, 57, Shevchenko Str., Ivano-Frankivsk, 76018, Ukraine
The electrochemical properties of composite titanium disulfide / nanoporous carbon in terms of its use in the storage of electrical energy are investigated. It is shown that laser irradiation of one of the components of the composite (TiS2) stabilizes the Coulomb efficiency of electrochemical capacitor type.
H.O. Sirenko, L.M. Soltys
Tribosurface Properties of Polymer Composite in Friction and Wear on Isotropic Rough Surface of Steel 45
Vasyl Stefanyk’ Precarpathian National University, 57, Shevchenko Str., Ivano-Frankivsk, 76025, Ukraine, e-mail:email@example.com
Regularities of change of roughness surfaces of steel 45 in friction and wear in a pair with polymer composite has been researched. The minorant rows of influence of spectral density moments on the intensity of wear of polymer composite based on aromatic polyamide and polytetrafluoroethylene and carbon fibers has been defined.
Keywords: roughness, intensity of wear, isotropic surface, friction, composite polymer material, moments of spectral density, minorant rows.
Research of Structure and Properties of Nickel Coatings, Modified Ultrafine Diamonds
Dnepropetrovsk national university of railway transport, e-mail:firstname.lastname@example.org
Researched composite electrolytic coatings deposited from nickel electrolyte containing ultrafine diamonds. Use of compounds of nanodiamonds surface modified nickel affects the structure and increases the microhardness of coatings.
Keywords: composition electrodeposits, ultrafine diamonds, structure, mechanical properties.
E.B. Kaganovich, S.O. Kravchenko, I.M. Krishchenko, E.G. Manoilov
Au (Ag) Nanoparticle Arrays Produced by Pulsed Laser Deposition
V. Lashkaryov Institute of Semiconductor Physics, NAS of Ukraine, 41, prospect Nauky, 03028 Kyiv, Ukraine, e -mail: email@example.com
Pulsed laser deposition from backward low-energy cluster flow of an erosion tourch on the substrates located on the target plane was used to obtain porous films with Au (Ag) nanoparticle arrays. YAG:Nd3+ laser beam (λ = 1,06 μm, Ep = 0,2 j, tp = 10 ns, fp = 25 Hz) scanned Au (Ag) target in vacuum chamber with argon pressure 10 to 100 Pa. The energy density was varied from 5 to 20 j/sm2, the laser pulse number – from 4500 to 45000. It was studied the dependences of structural and optical properties of films on the formation condition using AFM, SEM, TEM and UV-visible spectroscopy accordingly. In extinction spectra one can observe resonance band related with local surface plasmons witch allows for surface enhanced Raman scattering of rodomine 6G.
Keywords: Au (Ag) nanoparticles, local surface plasmon resonance, pulsed laser deposition, SERS substrates.
О.І. Demchyna, І.Yu. Yevchuk, R.Y. Musiy
Synthesis of Nanostructed Organic-Inorganic Films for Application in Solar Collectors and Fuel Cells
Department of Physico-chemistry of Combustible Minerals L.M. Lytvynenko Institute of Physico-organic Chemistry and Coal Chemistry NAS of Ukraine, 3а, Naukova Str., Lviv, 79053, Ukraine e-mail:firstname.lastname@example.org
Nanostructed organic-inorganic films were synthesized by method of photoinitiated polymerization of acrylate composition in the presence of sol-gel system on the basis of tetraethoxysilane (ТЕОS), аs well as at conducting of sol-gel process in situ in poly(vinylidene fluoride) matrix. Kinetic parameters of the process of photoinitiated polymerization were determined depending on the initial composition of polymerization system. Proton conductivity of the synthesized films was evaluated using impedance spectrometry. Nanocomposite coatings for application in solar collectors have been proposed. Their effectiveness in thermal energy absorption at irradiation by native solar radiation as well as at irradiation by imitator of solar radiation has been determined after maximal temperature of heating of the plates with investigated coatings.
Keywords: nanostructed organic-inorganic film, sol-gel technique, tetraethoxysilane, poly(vinylidene fluoride), photoinitiated polymerization, protonconducting membrane, thermoabsorbing coating.
R.O. Dzumedzey, V.V. Boryk
Performance Specifications of Thermoelectric Modules on the Example of the System "Solar Collector – Thermoelectric Generator"
Vasyl Stefanyk PreCarpathian National University 57, Shevchenko Str., Ivano-Frankivsk, 76018, Ukraine, E-mail:email@example.com
Presented system "Solar collector-thermoelectric generator", which is a combination of two sources of alternative energy in one device. The analysis of the existing market and TE modules are the advantages of our TE modules. Presented key indicators developed business plan.
Keywords: TE module, generation energy, payback period.
А.A. Druzhinin1,3, І.Т. Kogut1,2, Yu.N. Khoverko1,3, А.N. Vuitsyk1
Charge Carrier Transport of Polysilicon in SOI-Structures at Low Temperatures
1Lviv Polytechnic National University, Lviv, Ukraine, e-mail:firstname.lastname@example.org
2Vasyl Stefanyk Precarpathian National University, Ivano-Frankivsk, Ukraine
3International Laboratory of High Magnetic Fields and Low Temperatures, Wroclaw, Poland
The studies of temperature dependence of conductivity and magnetoresistance of SOI-structures with polysilicon resistors with carrier concentration 2,4•1018 сm-3 before recrystallization in temperature range 4,2 – 300 K are presented. The dimensions of polysilicon resistor in SOI-structure are 80mm × 8mm × 0,5 mm.
O.P. Ovcharenko1, V.I. Bilozertseva2, D.O. Gaman2
Optical Characteristics of Nonsplit Narrowband Frustrated Total Internal Reflection Filter
1V.N. Karazin Kharkiv National University, Svobody Sq. 4, 61022, Kharkiv, Ukraine, e-mail:email@example.com,
2National Technical University “Kharkiv Polytechnic Institute”, 21 Frunze str., 61002 Kharkiv, Ukraine ,e-mail:firstname.lastname@example.org
In this paper the five-layer narrowband frustrated total reflection filter having identical positions of S- and P- component pass bands have been considered. It was shown, that such filter properties are achieved by a special selection of middle frustrated total reflection filter layer thickness.
Keywords: optical narrowband filter, frustrated total internal reflection.