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Prykarpatsky A.K.,Ivan Franko State Pedagogical University of Drohobych | Prykarpatsky A.K.,AGH University of Science and Technology | Bogolubov N.N.,Abdus Salam International Center For Theoretical Physics | Bogolubov N.N.,Russian Academy of Sciences
Ukrainian Journal of Physics | Year: 2016

The classical Maxwell electromagnetic field and the Lorentz-type force equations are rederived in the framework of the Feynman proper time paradigm and the related vacuum field theory approach. The classical Ampere law origin is rederived, and its relationship with the Feynman proper time paradigm is discussed. The electron inertia problem is analyzed in detail within the Lagrangian and Hamiltonian formalisms and the related pressure-energy compensation principle of stochastic electrodynamics. The modified Abraham–Lorentz damping radiation force is derived, and the electromagnetic electron mass origin is argued. © A.K. PRYKARPATSKY, N.N. BOGOLUBOV, JR., 2016.

Korpan Y.I.,NASU Institute of Molecular Biology and Genetics | Soldatkin O.O.,NASU Institute of Molecular Biology and Genetics | Sosovska O.F.,NASU Institute of Molecular Biology and Genetics | Klepach H.M.,Ukrainian Academy of Sciences | And 6 more authors.
Microchimica Acta | Year: 2010

Novel formaldehyde-sensitive conductometric biosensors have been developed that are based on commercial bacterial formaldehyde dehydrogenase (FDH) from Pseudomonas putida and recombinant formaldehyde dehydrogenase (rFDH) from the yeast Hansenula polymorpha as the bio-recognition elements. The bio-recognition membranes have mono-layer architecture and consist of enzyme cross-linked with albumin and of the cofactors NAD (for FDH-based sensor) or NAD and glutathione (for rFDH-based sensor). This architecture of the biosensor allows the determination of formaldehyde without adding NAD and glutathione to the analyzed sample at every analysis and conducting measurements on the same transducer without cofactors regeneration since the bio-membrane contains it at high concentration (100 mM for NAD and 20 mM for glutathione). The response is linear in the range from 10 to 200 mM of formaldehyde concentration depending on the enzyme used. The dependence of the biosensor output signals on pH and buffer concentration as well as operational/storage stability and selectivity/specificity of the developed conductometric biosensors have been investigated. The relative standard deviation of the intra-sensor response did not exceed 4% and 10% for rFDH- and FDH-based sensors, respectively. The relative standard deviation of the inter-sensor response constituted 20% for both dehydrogenases used. The biosensors have been validated for formaldehyde detection in some real samples of pharmaceutical (Formidron), disinfectant (Descoton forte) and an industrial product (Formalin). A good correlation does exist between the concentration values measured by the conductometric biosensor developed in this work, an enzymatic method, amperometric biosensors developed earlier, and standard analytical methods of formaldehyde determination. © 2010 Springer-Verlag.

Druzhinin A.,Lviv Polytechnic | Ostrovskii I.,Lviv Polytechnic | Kogut I.,Lviv Polytechnic | Nichkalo S.,Lviv Polytechnic | Shkumbatyuk T.,Ivan Franko State Pedagogical University of Drohobych
Physica Status Solidi (C) Current Topics in Solid State Physics | Year: 2011

In this paper thermal conductivity of boron-doped Si and SiGe (3-5 at.% of germanium) whiskers has been measured by means of slightly modified 3ω -method in the range of 290-400 K. We have shown that obtained thermal conductivity temperature dependence of micron-scale whiskers agrees well with expected for bulk Si and SiGe with 3 to 5% of Ge content and at room temperature is equal to 150 and 100 Wm-1K-1respectively, which evidences the reliability of proposed modification of 3ω -method. Prospects of possible thermoelectric application of nanoscaled SiGe solid solutions have been considered. © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Yanishevsky V.,Ivan Franko State Pedagogical University of Drohobych
Journal of Physical Studies | Year: 2011

The optimization problem in the minority game model was investigated using a variational technique that is based on the logarithmic grand-canonical partition function inequality. In the introduced approach the β/P parameter expansion is not used as in the original papers. Fundamental relations were obtained in replica symmetric approximation for the minimum of the investigated variable as well as a system of equations for variational parameters. It was shown that the obtained results coincide with the results of the original papers.

Peleshchak R.M.,Ivan Franko State Pedagogical University of Drohobych | Kulyk N.Y.,Ivan Franko State Pedagogical University of Drohobych
Ukrainian Journal of Physics | Year: 2014

In the framework of the self-consistent electron-deformation model, the theory describing the formation of the quantum potential band profile and the energy levels of an electron and a hole in a stressed nanoheterosystem with coherently-strained quantum dots has been developed, and their dependences on the degree of doping of the nanoheterosystem matrix and the quantum dot surface concentration have been analyzed. The character of the quantum potential in the nanoheterosystem is shown to be governed not only by the mechanical component of the electron-deformation potential, but also by the energy of electrostatic interaction between charges in a vicinity of the quantum dot–matrix interface, where the latter induces additional quasi-triangular potential barriers and wells. © R.M. PELESHCHAK, N.YA. KULYK, 2014.

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