National Repository of Grey Literature 43 records found  beginprevious21 - 30nextend  jump to record: Search took 0.01 seconds. 
Thermodynamics of adsorption of natural organic matter onto activated carbon
Hirsch, Karel ; Pivokonský, Martin (advisor) ; Čermáková, Lenka (referee)
The presence of natural organic matter (NOM) in water resources can significantly affect the organoleptic properties of water, inhibit the processes of drinking water treatment and may be harmful to organisms and to human health. That is why the drinking water treatment process is therefore emphasizes the elimination of natural organic matter by the best available techniques. To remove NOM is currently proving to be the most effective adsorption process on the activited carbon (AC). The process of adsorption of natural substances on activated carbon affects many factors. Important factors affecting adsorption are the solution properties such as pH, ionic strength (IS), chemical composition and temperature of the solution. Due to different water temperatures, depending on the season, the temperature can significantly affect the process of NOM adsorption on activated carbon in drinking water treatment. The authors in their works devoted primarily to the effect of pH on adsorption and in the literature is shown little information on the effect of water temperature on the adsorption of natural organic matter. This thesis deals with thermodynamics of adsorption of natural organic matter to activated carbon. Bachelor's thesis in the form of research describes the basic properties of thermodynamics of...
Mineral assemblages, alteration reactions and transport model of the greisen formation in the Horní Blatná granite pluton, Krušné hory Mts.
Heřmanská, Matylda ; Dolejš, David (advisor) ; Štemprok, Miroslav (referee)
English abstract Hydrothermal systems related to highly evolved granitic magmas host diverse mineralization styles and provide an important source of economic metals. This master thesis concentrates on description and interpretation of geological structure, petrographic and textural variability, alteration zoning and calculation of time-integrated fluid fluxes recorded in highly evolved granites and tin-mineralized greisens of the Horní Blatná massif in the Western Krušné hory pluton. The massif is a composite intrusion, which consists of a large number of intrusive units emplaced during two stages. The first stage is represented by sparsely porphyritic fine-grained low-lithian annite granites that can be correlated with marginal granites (G2) of the Fichtelgebirge (Smrčiny) batholith or with intermediate granites (Walfischkopf type) of the Western Krušné hory (Erzgebirge) pluton. Intrusive batches of the second stage progressively evolve from medium- to coarse-grained serial high-lithian annite and zinnwaldite granites with topaz and rare tourmaline towards aphyric fine-grained zinnwaldite (or trilithionite) granites. This suite corresponds to the EIB2 and EIB3 facies of the younger intrusive complex in the Western Krušné hory (Erzgebirge) pluton and it can be compared to the G3 Waldstein and G4 units in...
Nerovnosti a jejich aplikace
TESAŘOVÁ, Jaroslava
This Thesis deals with mathematical inequalities, their use in mathematics and applications to thermodynamics. The main emphasis is placed on proofs of inequalities and solving examples. The following thing explains the mathematical concept such as norm or metric, needed to understand these procedures, and also some of basic concepts of thermodynamics. To understand this Thesis the knowledge of analysis and thermodynamics is required.
Hydrodynamic and thermal mode ling of reactive flow in the surroundings of intrusions
Jandová, Tereza ; Dolejš, David (advisor) ; Bruthans, Jiří (referee)
English Summary Intrusion of magma into the Earth's crust is associated with significant thermal perturbations, release of aqeuous fluids and formation of hydrothermal system. In order to better understand the feedback relationships between fluid flow, thermal evolution and permeability variations, we have modeled conductive and advective cooling of a shallow- crustal pluton using the SHEMAT software. Our model represents a two-dimensional cross section through the lithosphere with homogeneous material properties, whebery the heat and mass conservation equations are solved by finite difference method. We first calculate the stable lithospheric geotherm by emplying constant basal thermal flow of 40 mW m-2 and a constant surface temperature. Subsequently, we consider a rectangular magmatic intrusion emplaced at 5-10 km depth, which forms a contact aureole by conductive cooling. With time, a mushroom-like shape of the contact aureole is predicted. Inclusion of aqueous fluid flow into the model causes only a small alteration of thermal evolution mainly because the permeability is low and the fluid mass is negligible due to very low density under hydrothermal conditions. In addition to thermal effects, we have explored variations in hydraulic head in order to address the ensuing effects on the flow velocity. The...
Mathematical and computational modeling of shape-memory alloys
Benešová, Barbora ; Roubíček, Tomáš (advisor) ; Krejčí, Pavel (referee) ; Stefanelli, Ulisse (referee)
This dissertation thesis is concerned with developing a mesoscopic model for sin- gle crystalline shape-memory alloys including thermo-dynamically consistent thermo- mechanical coupling - here the term "mesoscopic" refers to the ability of the model to capture fine spatial oscillations of the deformation gradient by means of gradient Young measures. Existence of solutions to the devised model is proved in a "phase-field-like approach" by a scale transition from a microscopic model that features a term related to the interfacial energy; this scale transition from a physically relevant model justifies the mesoscopic relaxation. Further, existence of solutions is also proved by backward- Euler time discretization which forms a conceptual numerical algorithm. Based on this conceptual algorithm a computer implementation of the model has been developed and further optimized in the rate-independent isothermal setting; some calculations using this implementation are also presented. Finally, refinements s of the analysis in the convex case as well as a limit of the phase-field-like approach in this case are exposed, too.
Termodynamická analýza procesů v polymerní elektrolytické membráně palivového článku
Pavelka, Michal ; Maršík, František (advisor) ; Málek, Josef (referee)
Thermodynamic analysis of processes in electrolytic fuel cell membrane Michal Pavelka April 12, 2012 Abstract Hydrogen fuel cells1 may become a key technology of 21st century, and it is important to be able to describe their behavior, therefore. In this work we focus on hydrogen fuel cells with a polymer-electrolyte membrane. For the membrane we adopt an existing model2 . We for- mulate the model in the framework of the mixture theory which we develop similarly as has been done in the classical textbook of Mazur and de Groot3 . However, refining the concept of potential energy of a material point, we introduce new terms called internal potential ener- gies which enable us to describe macroscopic consequences of internal forces between water and polymer in the membrane and to describe the influence of gradient of surface tension of water in the membrane. We solve the model in 1D approximation. Consequently, we calculate the influence processes in the membrane have on efficiency of the fuel cell. 1 see for example Larminie, J. and A. Dicks. Fuel Cell Systems Explained. 2nd edition. John Wiley & Sons Ltd., 2003. ISBN 0-470-84857-X. 2 Weber, A. Z. and J. Newman. Transport in Polymer-Electrolyte Membranes I, II, III. J. Electrochem. Soc., 150 (7), A1008-A1015, 2003; 151 (2), A1311-A1325, 2004.; 151 (2), A1326-A1339,...
Thermodynamics of ideal cycles of IC engines in Matlab
Pavlíček, David ; Mauder, Tomáš (referee) ; Štětina, Josef (advisor)
Key aspect of this thesis is toolbox, which contains functions for calculate ideal combustion engine cycles. Thesis is divided into four parts. In the first part is briefly described history. The first chapter contains description of real combustion engine types. In the second part, which is covered by the second chapter, is located thermodynamic view. Third part is whole about MATLAB. From historical introduction through description of individual functions to example how toolbox can be used. In the last part is comparison of real combustion engine cycle with ideal one, which has been created by toolbox.
Basic thermal properties tester
Janečka, Marek ; Buršík, Martin (referee) ; Řezníček, Michal (advisor)
This work deals with metering heat feature of different types unyielding materials with the help of thermodynamic sensor. Here is above all surveyed, whether it is possible by the help of thermodynamic sensor mete heat conductivity and thermal resistance given to materials and subsequently accordingly to this to prove in part determine from measured results about what type of material walks.
Accurate positioning of pneumatic drives
Volf, Marek ; Nevrlý, Josef (referee) ; Marada, Tomáš (advisor)
Thesis starts with brief overview of the present role of pneumatic actuators. Further research is carried out in modelling and control of pneumatic actuators. A basic overview of thermodynamic laws is presented. These laws are used to assemble a mathematical model of the pneumatic drive. Subsequently the identification of model parameters is shown. A controller is propřed using fuzzy PID algorithms. Results are compared with the conventional PID controller.

National Repository of Grey Literature : 43 records found   beginprevious21 - 30nextend  jump to record:
Interested in being notified about new results for this query?
Subscribe to the RSS feed.