Artykuły (WFTIiMS)
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Pozycja Frequency dependence of the Kerr constant in nynas nytro 3000 oil determined by the polarimetric method(Wydawnictwo Politechniki Łódzkiej, 2018) Poborska, Julita; Dąbrówka, Dominika; Chwirot, Maksymilian; Ledzion, Rafał; Izdebski, Marek; Kucharczyk, WłodzimierzFrequency dependence of the Kerr constant in nynas nytro 3000 oil determined by the polarimetric method A frequency dependence of the Kerr constant K in transformer oil Nynas Nytro 3000 within a frequency range 117-5017 Hz is determined. An averaged value (2.30 ± 0.03)·10ˉ¹⁵ m/V² for K is obtained. The constant is found to be weakly frequency dependent and approaches its maximum 2.37·10ˉ¹⁵ m/V² at about 3000 Hz. The Kerr constant is of comparable value to that observed in other mineral oils employed previously in measurements of the quadratic electro-optic effect and the electrostriction in crystals.Pozycja Verification of one-dimensional models describing anisotropy of step growth(Wydawnictwo Politechniki Łódzkiej, 2017) Izdebski, Marek; Ledzion, RafałModels that allow to obtain directional dependencies of normal velocity of a straight step on the (001) face of Kossel crystal and its edge free energy are reviewed. The dependencies were considered in a wide range of crystal growth conditions, which showed some significant discrepancies between the models and limitations in the scope of their applicability. The results presented concern on one-dimensional kinetic and thermodynamic models of a single step.Pozycja Temperature dependence of the Kerr constant of fomblin M03.(Wydawnictwo Politechniki Łódzkiej, 2016) Ledzion, Rafał; Górski, Piotr; Izdebski, Marek; Kucharczyk, WłodzimierzThe Kerr constant B of perfluoropolyether Fomblin M03 has been determined within the temperature range 295-370K. At 300K the constant B was found to be equal to 2.8·10-15 m/V2. The measurements indicate that B varies inversely with temperature. Relatively low electro-optic response of the perfluoropolyether shows its usability in measurements of the quadratic electrooptic effect and the electrostriction in crystals.Pozycja Study of electrically induced orientational ordering in mineral oils on the example of orlen oil trafo en.(Wydawnictwo Politechniki Łódzkiej, 2016) Izdebski, Marek; Adamus, Monika; Jóźwiak, Ewelina; Ledzion, RafałA simple model of orientational ordering of molecules in the liquid under the influence of an applied sinusoidal electric field of low frequency is presented. The predicted theoretical dependencies of linear birefringence and light transmission coefficients on the intensity of the applied field were confirmed by experimental data obtained for transformer oil ORLEN OIL TRAFO EN. It was found that the intensity of orientational effects in the oil depends strongly not only on the current conditions, but also on the thermal history of the sample. Furthermore it is shown that the minimum amount of dissolved contaminants (e.g. polyethylene) strongly increases the effects. The results suggest that it is necessary to reconsider the techniques for measuring the Kerr effect in liquids associated with deformation of electron cloud, because the traditional approach does not take into account the orientational effects occurring simultaneously with the Kerr effect.Pozycja Analytical kinetic block model of crystal-mother-phase multilayer interface.(Wydawnictwo Politechniki Łódzkiej, 2015) Organiściak, Maciej; Izdebski, Marek; Ledzion, RafałSimple kinetic block model of multilayer crystal-mother-phase interface is proposed. The model leads to a system of differential equations which can be solved without the need to run Monte Carlo simulations. The proposed model is based on Bragg-Williams approximation (called also zeroth-order approximation), "solid-on-solid" assumption, and other assumptions common with thermodynamic Temkin model. Thus, it is possible to test the compliance of kinetic and thermodynamic approaches in a situation where all other significant differences between models are eliminated. Moreover, a comparison with the results of kinetic Monte Carlo simulations allows for better understanding of the impact of Bragg-Williams approximation.Pozycja The impact of aromatic additives on kerr effect in rapeseed oil.(Wydawnictwo Politechniki Łódzkiej, 2015) Komenda, Anna; Górski, Piotr; Ledzion, Rafał; Izdebski, MarekThe Kerr constant and quadratic electro-optic effect were determined for a few different rapeseed oils. The aim of the study was to investigate if aromatic additives in the oil influence its optical properties. Moreover, the effect of ageing of the oils on Kerr phenomena was observed.Pozycja Influence of electrode material spacing between electrodes on measurement of Kerr constant in castor oil.(Wydawnictwo Politechniki Łódzkiej, 2014) Perek, Artur; Ledzion, Rafał; Izdebski, Marek; Nowakowski, Krystian; Górski, PiotrThe influence of the electrode material and of the spacing between electrodes on Kerr constant in castor oil is investigated. It is shown that the spacing of the electrodes influences the measurement of Kerr constant whereas the electrode material has no influence on the results of the measurement.Pozycja Optimization of measurement conditions of Kerr constant in optical active liquids on the example of castor oil.(Wydawnictwo Politechniki Łódzkiej, 2014) Nowakowski, Krystian; Perek, Artur; Izdebski, Marek; Ledzion, Rafał; Górski, PiotrThe results of measurements of Kerr constant in castor oil, obtained by dynamic-polarimetric method are presented. Variable optical path length and four measurement setup configurations were used. They differed by the orientation of polarizer and of quarterwave plate and therefore they were non-equivalent when other, unwanted effects occurred. It was shown that the Kerr constant measurement performed with use of only one system configuration and one length of optical path may be strongly affected by other effects, however taking the arithmetic mean of two results obtained from appropriate system configurations significantly reduces this error. Theoretical dependences were fitted to the experimental results, which allowed for approximation of other constants, like dichroism, linear birefringence and optical activity induced by external electric field (electrogyration).Pozycja Modulation technique used for measurement of very weak linear birefringence and dichroism in liquids on the example of castor oil between metal electrodes.(Wydawnictwo Politechniki Łódzkiej, 2014) Izdebski, Marek; Ledzion, RafałA technique for measurement of very weak linear birefringence of the order of 10-7and dichroism in liquids is proposed. The method is based on the polarimetric technique. A characteristic feature is that the experimental setup enables the measurement of linear birefringence combined with electro-optic effect as well as the measurement of dichroism combined with electro-optic effect. The combination of the effect which does not show rapid changes with the effect which depends on alternating electric field allows to improve the sensitivity of the method (in comparison to the earlier static method). This was achieved by use of lock-in amplifier that measures only the selected harmonic with very high selectivity. The theoretical considerations are illustrated by the results of measurements for castor oil.Pozycja Analysis of measurement of quadratic electro-optic effect in castor oil(Wydawnictwo Politechniki Łódzkiej, 2013) Izdebski, Marek; Ledzion, Rafał; Kucharczyk, WłodzimierzThis works presents an extended theoretical analysis of the response of experimental setup to an applied electric field during measurements of electro-optic coefficients in optically active liquids using an optical polarimetric technique. The analysis includes liquids belonging to ∞ ∞, ∞ 2 and ∞ Curie symmetry groups and the following phenomena were taken into account: natural optical activity, natural linear birefringence, dichroism, and the effects induced by an applied electric field – linear and quadratic electro-optic effects and linear and quadratic electrogyration. The presented example concerns numerical error analysis for measurement of the quadratic electro-optic effect in castor oil, which exhibits the symmetry ∞ 2 between a pair of plane-parallel electrodes.