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L'viv, Ukraine

Lviv Polytechnic National University is the largest scientific university in Lviv. Since its foundation in 1844, it was one of the most important centres of science and technological development in Central Europe. In the interbellum period, the Polytechnic was one of the most important technical colleges in Poland, together with the Warsaw Polytechnic. Today the University is also the National Defense University . Wikipedia.

Pysh'yev S.,Lviv Polytechnic
Chemistry and Chemical Technology | Year: 2012

The fractions of diesel oil have been desulphurized via air oxidation without the catalysts in the presence of water. The products of sulphuric compounds oxidation were extracted by adsorption or joint adsorption and rectification. The samples of desulphurized diesel oil have been analyzed in accordance with reference documents after their treatment by alkali. The lubricity of the raw materials (straight-run diesel oil and hydrogenised fuel), desulphurized straight-run diesel oil (DSDO), hydrogenised fuel with DSDO additives and two samples of the fraction 553-623 K purified in the presence of water and without it has been determined. © Pysh'yev S., 2012.

Serheyev V.,Lviv Polytechnic
Chemistry and Chemical Technology | Year: 2012

Using a calorimetric method enthalpies of mixing of the binary systems of methylmethacrylate with acetonitryle, hexane, benzene, 1,2-diclorethane, and acetic acid at 293 K and atmospheric pressure have been measured. The concentration dependences of enthalpies of mixing were correlated by polynomials. © Serheyev V., 2012.

Zayachuk D.M.,Lviv Polytechnic
Journal of Magnetism and Magnetic Materials | Year: 2010

Peculiarities of applying the Curie-Weiss law to the analysis of the magnetic susceptibility of the impurities of the rare earth elements in the IV-VI crystals are examined. It is shown that the traditional approach to the determination of the paramagnetic Curie temperature of ferromagnets and antiferromagnets applied to the impurities of ferromagnetic and antiferromagnetic elements in the doped crystal may lead to fundamental mistakes. The results of this examination are used to analyze the high temperature magnetic susceptibility of Eu and Gd impurities in the PbTe doped crystals grown from the melt using the Bridgman method. It is established that the doping of PbTe with Eu leads to the formation of ferromagnetic inclusions and the same doping with Gd leads to the formation of antiferromagnetic inclusions in the crystal. It is shown that these inclusions are most likely the complexes based on the europium or gadolinium oxides EuO and Gd2O3, respectively. © 2009 Elsevier B.V. All rights reserved.

Bryk T.,Ukrainian Academy of Sciences | Bryk T.,Lviv Polytechnic
European Physical Journal: Special Topics | Year: 2011

A short review of analytical and numerical results, obtained for collective dynamics in liquid metals and alloys within a theoretical approach of Generalized Collective Modes (GCM) is presented. The GCM approach permits to represent dynamic structure factors in wide ranges of wave numbers and frequencies as a sum of contributions from hydrodynamic and non-hydrodynamic processes. The origin of collective modes that make important contributions to dynamic structure factors beyond the hydrodynamic regime in liquid metals and alloys is discussed. © 2011 EDP Sciences and Springer.

Malyk O.,Lviv Polytechnic
Diamond and Related Materials | Year: 2012

The processes of the charge carrier scattering on the short-range potential caused by interaction with polar and nonpolar optical phonons, piezoelectric and acoustic phonons, static strain, neutral and ionized impurities in wurtzite n-GaN with impurity concentration 1.1 × 10 16 cm - 3 ÷ 1.9 × 10 18 cm - 3 and in wurtzite p-GaN with impurity concentration 1.9 × 10 19 cm - 3 ÷ 2.6 × 10 20 cm - 3 are considered. The temperature dependences of electron mobility in the range 15 ÷ 500 K and hole mobility in the range 100 ÷ 1000 K are calculated. © 2011 Elsevier B.V. All rights reserved.

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