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Analysis of the Hydrated ions Clusters Impact on the Liquid/Liquid Interface
Mareček, Vladimír ; Samec, Zdeněk ; Trojánek, Antonín
Open circuit potential (OCP) measurements of the partition of tetrapentylammonium chloride (TPeACl) at the water/1,2-dichloroethane (DCE) interface reveal two remarkable processes. The first one is characterized by a decay of the OCP from its expected equilibrium value. This process has been ascribed to the extraction of the salt driven by its accumulation in the hydrated salt clusters in the DCE phase. The second process is characterized by the short-term potential spikes overlapping the long-term OCP records. These spikes are assumed to be associated with the collision and fusion of the hydrated salt clusters produced by the former process with the water/DCE interface.
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Ion Transfer Voltammetry across the Polarized Ionic Liquid/Water Interface: Base for Electrochemical Sensors
Langmaier, Jan ; Samec, Zdeněk
Some electrochemical techniques such as voltammetry at the polarized interfaces between two\nimmiscible electrolyte solutions (ITIES) represent interesting alternatives to classical\nelectrochemistry. The benefit of the ion transfer voltammetry lies in the possibility of detection\nof ionic species which are not otherwise redox active. The methodology enables apart of direct\ndetermination of ionic samples (including pharmaceutical and clinical ones) also to monitor\nreaction processes (acido-basic, enzymatic, etc.), determination of reaction substrates and\nproducts in one experimental step, evaluation of reaction and transport kinetics, and estimation\nof lipophilicity of involved species.
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The Relation of Work to Zeus' World Order in Hesiod's Works and Days
Samec, Zdeněk ; Fischerová, Sylva (advisor) ; Souček, Jan (referee)
(in English) The presented thesis is dealing with the ethics of work in the world as described by ancient Greek poet Hesiod in his famous didactic epos Works and Days. In the first part of the thesis (chapters 1 and 2), it is assumed that Hesiod's ethics are anchored in a particular situation, in which he, as a Boeotian farmer, found himself due to his dispute with his brother Perses. In the next part, firstly three major myths in the Works and Days are analyzed and the importance of work is set in a wider context of Hesiod's religious and ideological beliefs (chapter 3); subsequently our analysis is supplemented by a broader reflection of work, exertion, recreation, good and evil (chapter 4). In conclusion we finally try to answer the question of the place of work in the world order as determined by Zeus' will.
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Mechanism of the Water Clusters Formation in the Organic Phase in the Presence of Hydrated Ions
Holub, Karel ; Samec, Zdeněk ; Mareček, Vladimír
A two-electrode cell comprising a liquid/liquid interface is used to study the water clusters formation in the organic solvent phase following the extraction of tetraalkylammonium chloride (TAACl) from the aqueous phase. The change in the concentration of the common TAA+ ion on the aqueous side of the interface is monitored by the open circuit potential measurements. It is shown that the amount of TAACl extracted into the organic phase exceeds considerably the limit determined by the concentration of Cl- in the organic phase at a given interfacial potential difference and the electroneutrality condition. A mechanism is proposed including an accumulation of the excess TAACl in the water clusters formed from the hydration shell of the Cl- ions, water already dissolved in the organic phase, and additional water extracted from the aqueous phase. At higher concentration of TAACl in the aqueous phase this process leads to the formation of emulsion in the organic phase.
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The Theory of Cognition in Thomas Aquinas
Samec, Zdeněk ; Novák, Lukáš (advisor) ; Válová, Dita (referee)
(in English): The thesis "The Theory of Cognition in Thomas Aquinas" investigates the conception of cognition in the work of one of the most significant medieval thinkers, saint Thomas Aquinas. The first part of the thesis is devoted to the elements of Thomas's conception of cognition, i.e. sense perception, intellectual grasp of essences and Thomas's theory of intentional mediation of cognition (species sensibilis and species intelligibilis). In the following part of the thesis Thomas's theory of intentionality is considered in detail, with approaches of the so-called direct realism (held by D. Perler) and representationalism (held by R. Pasnau) taken in account. The thesis ends by its author's own evaluation of the controversy between representationalism and direct realism.
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Applications of ionic liquids in electrolytes for amperometric gas sensors and Li-ion batteries.
Nádherná, Martina ; Opekar, František (advisor) ; Samec, Zdeněk (referee) ; Zima, Jiří (referee)
Mgr. Martina Nádherná PhD. Thesis Applications of ionic liquids in electrolytes for amperometric gas sensors and Li-ion batteries SUMMARY The dissertation presents the results of preparation and characterisation of new aprotic electrolytes based on ionic liquids for the solid-state electrochemical gas sensors and for the electrochemical energy storage devices - secondary lithium-ion batteries. In the part dealing with the solid-state amperometric sensor for NO2 research was aimed at development of new solid electrolyte. This electrolyte is developed as a system of ionic liquid embedded in the structure of a polymer, when the ionic liquid joints the properties of a solvent and a dissolved salt. The electrolyte therefore does not contain any volatile component and is long-term chemically and electrochemically stable. Several series of electrolytes were prepared with different polymers or macromonomers and imidazolium-based ionic liquids. The composition, especially the polymer-IL ratio was optimized. The electrolytes were successfully tested in a solid-state NO2 sensor with a gold minigrid serving as the indicating electrode. The research included the determination of basic electrochemical parameters and study of the sensor behaviour under different conditions. The influence of atmosphere humidity,...
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