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Douayar A.,Mohammed V University | Abd-Lefdil M.,Mohammed V University | Nouneh K.,Mohammed V University | Prieto P.,Autonomous University of Madrid | And 3 more authors.
Applied Physics B: Lasers and Optics | Year: 2013

Photoinduced linear electrooptical (EO) effect was studied for Zinc oxide nanofilms doped by Nd. We have chosen Nd rare earth impurity with different contents to explore its influence on photoinduced EO. The kinetics of the photoinduced EO changes was studied. We have chosen the bicolor coherent 10 ns Nd:YAG laser pulses with power densities varying up to about 1 GW/cm2 as the photoinducing beam. The enhancement of the photoinduced liner EO and its relaxation was explored. Additionally, the study of the photoinduced trapping levels within the energy gap was performed and the explanation of the obtained results is given. © 2013 Springer-Verlag Berlin Heidelberg. Source

Khyzhun O.Y.,Ukrainian Academy of Sciences | Ocheretova V.A.,Kharkiv Polytechnic Institute | Fedorchuk A.O.,Lviv National University of Veterinary Medicine and Biotechnologies | Parasyuk O.V.,European University at Kiev
Optical Materials | Year: 2014

We report on studies of the electronic structure of Ag 2CdSnS4 single crystal grown by the horizontal gradient freeze technique. For the crystal under consideration, X-ray photoelectron core-level and valence-band spectra for pristine and Ar+-ion irradiated surfaces have been measured. The present X-ray photoelectron spectroscopy (XPS) results indicate that Ag2CdSnS4 single crystal surface is very rigid with respect to Ar+ ion-irradiation. In particular, Ar+ bombardment of the single crystal surface does not induce any significant changes of values of the binding energies of core-level electrons as well as the energy distribution of electronic states within the valence-band region. The Ar+ bombardment does not change the elemental stoichiometry of the Ag2CdSnS4 surface. For the Ag2CdSnS4 compound, the X-ray emission bands representing the energy distribution of the valence Ag d, Cd d and S p states were recorded and compared on a common energy scale with the XPS valence-band spectrum. Results of such a comparison indicate that the S 3p states contribute predominantly in the upper and central portions of the valence band of the Ag2CdSnS4 single crystal. In addition, our data reveal that the Ag 4d and Cd 4d states contribute mainly in the central portion and at the bottom of the valence band, respectively. © 2014 Elsevier B.V. All rights reserved. Source

Fedorchuk A.O.,Lviv National University of Veterinary Medicine and Biotechnologies | Parasyuk O.V.,European University at Kiev | Kityk I.V.,European University at Kiev | Kityk I.V.,Czestochowa University of Technology
Materials Chemistry and Physics | Year: 2013

A new approach to describe anion sub-lattice for chalcogenide compounds is proposed. The approach is developed on the base of wurtzite and sphalerite structures and includes consideration of the second coordination sphere of anion atoms. A variety of discussed examples show that the second coordination surrounding may be formed both by single anion atoms and by atom pairs or more complex configurations. Considering some chalcogenide compounds, the efficiency of such approach is demonstrated for the search of some similarities between the compounds and for optimization of corresponding quantum chemical calculations. © 2013 Elsevier B.V. All rights reserved. Source

Fedets O.M.,Lviv National University of Veterinary Medicine and Biotechnologies
Ukrain'skyi Biokhimichnyi Zhurnal | Year: 2014

Data about classification, nomenclature, structure, substrate specificity and role of many glutathione transferase's isoenzymes in cell functions have been summarised. The enzyme has been discovered more than 50 years ago. This family of proteins is updated continuously. It has very different composition and will have demand for system analysis for many years. Source

Fedorchuk A.O.,Lviv National University of Veterinary Medicine and Biotechnologies | Gorgut G.P.,Lesya Ukrainka Eastern European National University | Parasyuk O.V.,Lesya Ukrainka Eastern European National University | Lakshminarayana G.,Los Alamos National Laboratory | And 2 more authors.
Journal of Physics and Chemistry of Solids | Year: 2011

In this work, we report on the structural and optical properties of novel Ag0.98Cu0.02GaGe3Se8 single crystals that were synthesized by the BridgmanStockbarger technique. We have performed illumination by 10.6 μm CO2 pulsed laser working in the microsecond time duration regime. Such illumination allows causing substantial changes for both pure electronic nonlinear optical effects like optical second harmonic generation as well as piezooptical effects described by the fourth rank tensors. The measurements of the piezo-optical effects were carried out at different temperatures. The effects are observed only during the IR CO 2 laser illumination and are disappeared after switching off the illumination. Simultaneously the IR induced optical second harmonic generation at Er:glass laser fundamental wavelength 1540 nm was performed during illumination by nanosecond Nd:YAG and Er3:glass laser. The observed effects allow to use the studied materials as promising for IR-optoelectronic devices. © 2011 Elsevier Ltd. All rights reserved. Source

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