29 research outputs found

    Modification of the Two-Point Scaling Theory for the Description of the Phase Transition in Solution. Analysis of Sodium Octanoate Aqueous Solutions

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    On the basis of conventional scaling theory, the two-point scaling theory was modified in order to describe the influence of composition on the partial molar heat capacity and volume during the micellization process. To verify the theory, isobaric heat capacities and densities of aqueous sodium octanoate solutions were measured over wide composition and temperature ranges and the modified approach was used to analyze the calculated partial molar heat capacities and volumes of the surfactant in water. The results obtained indicate that the micellization process is subject to the scaling laws. The results were compared with those for other systems. Peculiar behavior of the critical indices was observed and correlated with the structure of the micelles

    The differences in thermal profiles between normal and leukemic cells exposed to anticancer drug evaluated by differential scanning calorimetry

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    Chronic lymphocytic leukemia (CLL) is a heterogenous disease with an imbalance between apoptosis and cell proliferation. Therefore, the main goal in CLL therapy is to induce apoptosis and effectively support this process in transformed B lymphocytes. In the current study, we have compared differential scanning calorimetry (DSC) profiles of nuclei isolated from CLL cells and normal mononuclear cells exposed to cladribine or fludarabine combined with mafosfamide (CM; FM), and additionally to CM combined with monoclonal antibody—rituximab (RCM) for 48 h, as well as in culture medium only (controls). Under current study, the mononuclear cells from peripheral blood (PBMCs) of healthy individuals have been included. The obtained results have shown the presence of thermal transition at 95 ± 5 °C in most of nuclear preparations (92.2 %) isolated from blood of CLL patients. This thermal characteristic parameter was changed after drug exposure, however, to a different extent. These thermal changes were accompanied by the decrease of cell viability, an elevation of apoptosis rate and the changes in expression/proteolysis of poly(ADP-ribose)polymerase-1—main marker of apoptosis. Importantly, in DSC profiles of nuclear preparations of PBMCs from blood of healthy donors exposed to investigated drug combinations and control CLL cells, the lack of such changes was observed. Our results confirmed that DSC technique complemented with other biological approaches could be helpful in tailoring therapy for CLL patients.Research was sponsored by Grant from the Polish National Science Centre (No. 2011/01/B/NZ/0102); Results of presented study were partially presented in oral presentation on 2nd Central and Eastern European Conference on Thermal Analysis and Calorimetry in Vilnius, Lithuania, 201

    Electromagnetic calculation of a transducer with complicated movement based on common magnetic circuit

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    This document contains results of research on complex motion common magnetic circuit electromagnetic converter characteristic that allows making independent axial and rotary shaft motion. The converter in addition to linear-rotary mechanism consists of two drive rotors and one common magnetic circuit excitator. Such a solution allows to reduce volume of the machine and makes it easier to use. The paper cites design intent and possible structure of the device. Phenomenon of common magnetic circuit adverse effect on correct operation of device is discussed. The concept of using relative error as a way to evaluate the influence of that phenomenon in the torques is discussed. Waveforms of determined relative errors for all possible cases is presented. Furthermore the concept of average relative error is defined and its use as a quantitative method of assessing the degree of common circuit impact is indicated. Definition of relative error ripple factor is given, and its usage is shown. Winding inductance calculation based on free FEM application is shown and its influence on control strategy and power system.W pracy przedstawiono wyniki postępu prac nad elektromechanicznym przetwornikiem położenia o wspólnym obwodzie magnetycznym, znamiennym tym, że umożliwia wykonywanie niezależnego ruchu liniowo obrotowego wałka wykonawczego. Przekładnik oprócz mechanizmu liniowo- obrotowego składa się z dwóch wirników napędzających wspomniany mechanizm oraz wspólnego wzbudnika stanowiącego wspólny obwód magnetyczny. Zastosowanie takiego rozwiązania, umożliwia zmniejszenie objętości maszyny, czyniąc ją łatwiejszą w zastosowaniu. W pracy przywołano założenia konstrukcyjne i możliwe struktury wykonania urządzenia. Omówiono zjawisko niekorzystnego wpływu wspólnego obwodu magnetycznego na poprawną pracę przetwornika. Wskazano wykorzystanie pojęcia błędu względnego jako sposobu oceny stopnia oddziaływania wymienionego zjawiska na moment obrotowy wirników. Zaprezentowano przestrzenne przebiegi wyznaczonych błędów względnych, dla wszystkich możliwych przypadków. Zdefiniowano ponadto pojęcie średniego błędu względnego i wskazano jego zastosowanie jako ilościowego sposobu oceny stopnia oddziaływania wspólnego obwodu. Zdefiniowano pojęcie współczynnika tętnienia błędu momentu i wskazano jego zastosowanie. Omówiono wyznaczenie indukcyjności uzwojeń w darmowym programie do obliczeń polowych i jej wpływu na projektowanie układu zasilania sterownika oraz strategii sterowania

    The electromagnetic calculations of complex motion common magnetic circuit electromagnetic converter

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    This document contains results of research on complex motion common magnetic circuit electromagnetic converter characteristic that allows making independent axial and rotary shaft motion. The converter in addition to linear-rotary mechanism consists of two drive rotors and one common magnetic circuit excitator. Such a solution allows to reduce volume of the machine and makes it easier to use. The paper cites design intent and possible structure of the device. Phenomenon of common magnetic circuit adverse effect on correct operation of device is discussed. The concept of using relative error as a way to evaluate the influence of that phenomenon in the torques is discussed. Waveforms of determined relative errors for all possible cases is presented. Furthermore the concept of average relative error is defined and its use as a quantitative method of assessing the degree of common circuit impact is indicated. Definition of relative error ripple factor is given, and its usage is shown. Winding inductance calculation based on free FEM application is shown and its influence on control strategy and power system

    Description of reaserch on complex motion electromechanical converter with common magnetic circuit

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    The paper describes research on evolution of complex motion electromechanical converter. So far simultaneous generation of slidinig and rotating motion was done using at least two excitators. This paper presents solution which two excitators are replaced by a single one having common magnetic path and two separated electric circuits. The main advantage of common magnetic core is reduction of electromechanical converter volume, which simplifies technical application. Apart from introduction of main principle of common magnetic circuit, this paper shows two examples of common core complex motion electromechanical converter: radial flux, and axial flux application. Furthermore first results of FEM analyze of radial application and development orientation are presented

    The electromagnetic calculations of complex motion common magnetic circuit electromagnetic converter

    No full text
    This document contains results of research on complex motion common magnetic circuit electromagnetic converter characteristic that allows making independent axial and rotary shaft motion. The converter in addition to linear-rotary mechanism consists of two drive rotors and one common magnetic circuit excitator. Such a solution allows to reduce volume of the machine and makes it easier to use. The paper cites design intent and possible structure of the device. Phenomenon of common magnetic circuit adverse effect on correct operation of device is discussed. The concept of using relative error as a way to evaluate the influence of that phenomenon in the torques is discussed. Waveforms of determined relative errors for all possible cases is presented. Furthermore the concept of average relative error is defined and its use as a quantitative method of assessing the degree of common circuit impact is indicated. Definition of relative error ripple factor is given, and its usage is shown. Winding inductance calculation based on free FEM application is shown and its influence on control strategy and power system
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