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Influence of polyelectrolyte biopolymers on transport of ions
Kolesa, Pavel ; Kalina, Michal (referee) ; Klučáková, Martina (advisor)
This bachelor thesis was focused on the study of interaction of cationic biopolymer with model diffusion probe (basic organic dye) in the gel media by diffusion processes. The main aim was optimization of simply laboratory diffusion technique (unsteady diffusion in a cuvette) because of study on interactions of chosen biopolymer with model compound depending on temperature. Cationic chitosan was chosen as model biopolymer. The model diffusion compound was chosen organic anionic dye Acidal Black 10B (C.I. 20470). Diffusion processes in plastic cuvettes were realized by transport of dye in a hydrogel media based on thermoreversible polysaccharide – agarose. The important content of this method is a monitoring of the time progression of diffusion profile by UV-VIS spectrophotometry. Important part of this work was characterization of hydrogel medium and biopolymers by basic physical-chemical methods. This bachelor thesis is focused on reactivity of chitosan and its behavior in different systems. Unsteady diffusion in cuvettes appears to be a universal method for the study on reactivity of biopolymers.
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Influence of pH and ionic strength on barrier abilities of humic substances
Přítulová, Marie ; Kratochvílová, Romana (referee) ; Klučáková, Martina (advisor)
The main aim of this bachelor thesis is the study of humic acids and their barrier properties. The reactivity of humic acids was studied by simple laboratory diffusion techniques in plastic diffusion cells. This thesis is mainly focused on the through-diffusion processes in hydrogel media. Hydrogel media were based on the thermoreversible polysaccharide (agarose) with or without addition of humic acids. The rate of reactivity of humic acids was compared by the interactions with organic cationic dye – methylene blue. The influence of ionic strength and pH was tested as well.
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Study on Reactivity of Cationic Biopolymer by Simple Diffusion Techniques
Tesařová, Barbora ; Kalina, Michal (referee) ; Smilek, Jiří (advisor)
This bachelor thesis is focused on study of chitosan reactivity by simple diffusion processes realized in hydrogel media based on agarose. Mechanical properties studied by oscilatory measurements and the pore size were determined at agarose gels with the addition of chitosan as the main parameters influenced the transport properties. The main goal of this work is the investigation the reactivity of chitosan. Agarose is used only as a supporting matrix for the formation of a hydrogel. The state of the art is aimed primarily on the study of chitosan reactivity based on already published scientific papers.
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Reaction synthesis of bulk intermetallic materials in Ti Ni system form kinetic spraying deposits
Dyčka, Martin ; Moravčík, Igor (referee) ; Jan, Vít (advisor)
Bachelor’s thesis deals with intermetallic compounds which are formed in nickel-titanium binary system. The theoretical part of this thesis deals with the best known titanium based intermetallics, diffusion and possible processing technologies of intermetallic materials. In experimental part, a nickel-titanium coating created by cold spray technique was used. The changes in microstructure depending on annealing temperature were analysed. The results contain photographs of microstructure and fractures, values of microhardness and results of chemical analyses.
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A method for the solution of non-spherical (fiber) particles deposition by means of the Fokker-Planck equation for ODF in a laminar flow
Kopečková, Barbora ; Knotek, Stanislav (referee) ; Jícha, Miroslav (advisor)
The Bachelor's thesis deals with a deposition efficiency for a fibers by various mechanisms of a deposition. It explains deposition efficiency by diffusion, by sedimentation and by impaction. The implementation of Peterlin's analytical solution for calculation of the ODF, which is used for individual efficiencies solution, is also mentioned. Afterwards, the thesis summarizes formulas for calculation of particular efficiencies derived for spherical particles and recomputation appropriate parameters for fibers. The purpose of the thesis is to create graphs, which illustrate deposition efficiencies dependence by various mechanisms on the aspect ratio of fibers. Another goal is the graphs creation, which shows juxtaposition for various breathing modes for given deposition mechanisms. The software MATLAB is used for the whole calculation process and graphs plotting.
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Transport properties of agarose hydrogels
Vlasák, Jan ; Kalina, Michal (referee) ; Klučáková, Martina (advisor)
This thesis deals with the transportation processes of electrolytes using simple organic dyes as diffuse probes. The main goal of the work concerns a study of a diffusion mobility of the selected probes being in a form of simple organic dyes in a hydro-gel matrix based on a thermo-reversible linear polysaccharide, i.e., agaroses, functioning as semi-permeable membranes. The thesis describe diffusion processes used for determination of the basic diffusion parameters such as an efficient diffusion coefficient, reputed diffusion coefficient, separating coefficient, concentration of the dye in a gel and the time needed for the diffusion going throughout the entire layer of the gel. Attention is paid also to the environment in which the diffusion processes are implemented (in particular in view of the gel-like samples), porousness of the structure and its mechanical properties.
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Reaction synthesis of bulk Fe-Al intermetallic materials
Dyčková, Lucie ; Hutařová, Simona (referee) ; Jan, Vít (advisor)
Bachelor’s thesis deals with iron aluminides. In literature analysis are the best known and the most widely used intermetallics materials, diffusion and other possible processing technologies of intermetallic materials. In experimental part was used sprayed coating. This sprayed coating was produced by cold gas-dynamic spray. In this thesis were analysed changes in microstructure of iron aluminides depending on annealing temperature. This thesis contains photographs of microstructure and analyses from electron microscopy and measurement of microhardness.
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Optimalization of experimental method for study on penetration of humic acids into leaves.
Smilková, Marcela ; Pekař, Miloslav (referee) ; Sedláček, Petr (advisor)
This bachelor’s thesis is focused on the study of penetration of humic substances trough the plant cuticle. The main objective of the thesis aimed at a literature search on foliar fertilization and transport of substances in the plant leaves. According to the literature search, experimental technique was suggested and tested in order to study penetration of humic substances through the leaf cuticle. The method consists of observation of diffusion transport of humic acids between two inert agarose gels separated by the plant cuticle. Cuticles were prepared by the means of three different isolation procedures.
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Diffusion processes in modified humic gels
Grunt, Jakub ; Sedláček, Petr (referee) ; Klučáková, Martina (advisor)
This bachelor thesis presents a study on diffusion of cupric ions in humic acid gels. A total of four types of samples were made during a modified preparation of gels. Humic acids were dissolved either in sodium hydroxide or in the solution of sodium triphosphate. Subsequently, hydrochloric acid and magnesium chlorid were used for "precipitation" of the gels. Gained samples differed particularly in the nature of interactions forming their gel structures. All the samples were subjected to diffusion experiments. Two different methods – constant-source diffusion and immediate planar source diffusion – were used to assign the diffusion coefficients. Both these methods were based on monitoring how the diffusion profiles of cupric ions in gels develop in time and on assigning the overall diffusion flow. The aim of the thesis was to assess the impact of gel preparation procedure and resultant structure on diffusion coefficients of cupric ions and their transport attributes in gels in general. Two different methods of diffusion inquiry were chosen particularly to assess the impact of cupric ion concentration on the diffusion coefficient.
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Semiconductor nanowire growth modelling
Kovács, Roland ; Bartošík, Miroslav (referee) ; Kolíbal, Miroslav (advisor)
This bachelor’s thesis deals with modelling of semiconductor nanowires growth. The work describes the mechanism of growth using the VLS method. The main objective is to simulate the distribution of eutectic material in a droplet in the initial stage of growth. Mathematical models describing different situations of material diffusion in the droplet were depeloped. The simulation model is programmed in MATLAB.
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