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Effect of surface of semiconductor nanocrystals on their properties: investigation by laser spectroscopy
Preclíková, Jana
The topic of the diploma thesis is chemical treatment of the surfaces of semiconductor nanocrystals CdS and CdSe in the form of thin nanocrystalline films prepared by chemical bath deposition. The evolution of photoluminescence and absorption spectra was investigated under treatment by water, toluene, butylamine, pyridine and hydrogen peroxide. The strongest changes were observed by samples soaked in water, pyridine and aqueous solution of pyridine. The observed effects were explained by partly dissolving of nanocrystals by water and affecting behaviour of photoexcited holes in the presence of the strong hole acceptor pyridine. The second part of this diploma thesis deals with photochromic properties of silver nanoparticles in a titanium oxide matrix. The photochromic behaviour of the samples was examined in detail. A phenomenological model of photochromic changes was suggested in analogy with the hole burning spectroscopy. In order to better understand the microscopic processes in this composite material other experiments were realized - e.g. samples were UV irradiated, or laser illuminated under lowered air pressure, pump & probe experiment. Under laser irradiation optical extinction of some nanoparticles was decreased. Simultaneously, changes of plasmon resonances of the rest of nanoparticels were...
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Celda Klouček - personality and work
Teichmanová, Jana ; Prahl, Roman (advisor) ; Vondráček, Radim (referee)
This work is deling with personality and work of Celda Kloucek, a sculptor and ornamentalist living at the turn of 20th century. Celda Kloucek was born 6th December 1855 in Senomaty near Rakovnlk. Advised by his patron Milller, he decided to accept a position with ornamentalist sculptor Otto Lessing in Berlin, where he got his first professional training. Kloucek turned out to be an excellent sculptor, especially in ornamental construction work. The contracts were diverse and he learned to work with many different materials. In 1879 he enroled in professor Otto Konig special course at Arts and Crafts School in Vienna. After three years, he became a reader at Arts and Crafts School in Frankfurt am Main. In 1888, he opened his atelier at Arts and Crafts School in Prague. He was teaching here for twenty-eight years. Many recognized artists emerged from his atelier, all of them adhering to Kloucek's emphasis on clarity of composition and simplicity of the ornament. Kloucek's work evolved from ornamental creations on house exteriors in neo-Rennaissance and neo-baroque style to naturalism, and finally to Art Noveau, in which he created his master pieces: Wohanka house portal (1898), Museum of Western Bohemia in Pilsen (1900-1901), Prague Credit bank (1902), Blecha house (1904), and Order of the Cross monastery...
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Effect of surface of semiconductor nanocrystals on their properties: investigation by laser spectroscopy
Preclíková, Jana ; Malý, Petr (advisor) ; Franc, Jan (referee)
The topic of the diploma thesis is chemical treatment of the surfaces of semiconductor nanocrystals CdS and CdSe in the form of thin nanocrystalline films prepared by chemical bath deposition. The evolution of photoluminescence and absorption spectra was investigated under treatment by water, toluene, butylamine, pyridine and hydrogen peroxide. The strongest changes were observed by samples soaked in water, pyridine and aqueous solution of pyridine. The observed effects were explained by partly dissolving of nanocrystals by water and affecting behaviour of photoexcited holes in the presence of the strong hole acceptor pyridine. The second part of this diploma thesis deals with photochromic properties of silver nanoparticles in a titanium oxide matrix. The photochromic behaviour of the samples was examined in detail. A phenomenological model of photochromic changes was suggested in analogy with the hole burning spectroscopy. In order to better understand the microscopic processes in this composite material other experiments were realized - e.g. samples were UV irradiated, or laser illuminated under lowered air pressure, pump & probe experiment. Under laser irradiation optical extinction of some nanoparticles was decreased. Simultaneously, changes of plasmon resonances of the rest of nanoparticels were...
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Travel Cost Analysis in Recreation Demand Models.
Schlehr, Miroslav ; Melichar, Jan (advisor) ; Vojáček, Ondřej (referee)
This work analyses the difference between perceived and computed travel cost data in Recreation Demand Models. Travel cost in this study includes only the cost which stems from the distance which the visitor had to overcome in order to get to recreation site. This study has examined the use of vector model in Geographical Information System as a source for computed data. Three different approaches of calculating travel costs were analysed in single-site model of recreation model. This work also focuses on current composition of travel cost in Travel Cost Method, describes the constraints of this method and consequences for further research.
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Current condition and historical development of waterlogged meadows in the region of Říčany
Horina, Lukáš ; Kindlmann, Pavel (referee) ; Münzbergová, Zuzana (advisor)
During a cooperation on a project of the orchid protection in the Říčany Ecocenter number of questions arose. Firstly it is a question of an identification of orchid meadows. Then finding main parameters of an environment, which influence the occurence of Dactylorhiza majalis. Consequently finding factors that influence the size of population of Dactylorhiza majalis. And eventually finding a suitable management for the orchid meadows. I was trying to find the answers mainly via a comparison of orchid and similar non orchid meadows. I was comparing species composition, local conditions and historical use of the site. I decided for the method of phytocenologic snaps and Ellenberg numbers for detection of the local conditions. Historical maps were used for finding the historical use. Data were processed by statistic analytical methods (PCA,RDA) When comparing orchid and non orchid meadows I found out that they differ conclusively in species composition and in number of species. I found plant species according to which it is possible to determine a potentional orchid location. Furthermore I found out that orchid and non orchid meadows differ in values of parameters of an environment. Consequently I found that these parameters are continentality, humidity and trophy of the site. Then I found out that humidity...
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Mobilization of neutral compounds by inorganic and small organic ions in capillary electrophoresis
Křížek, T. ; Martínková, E. ; Kubíčková, A. ; Hladílková, Jana ; Coufal, P. ; Heyda, J. ; Jungwirth, Pavel
The present study shows that neutral low-molecular-mass compounds that are presumed to possess zero electrophoretic mobility and are thus used as markers of electroosmotic flow in capillary electrophoresis can acquire electrophoretic mobility due to ion-specific interactions with constituents of background electrolyte. Therefore, these neutral markers, such as thiourea or dimethyl sulfoxide, can be separated in electric field and their migration order can vary depending on background electrolyte composition. This observation has some important implications for analytical and physico-chemical measurements using capillary electrophoresis because the choice of the marker-background electrolyte combination can influence the results of the measurement.
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The dictate of beauty as a subject-matter in the prose with a teenage heroine
Hřídelová, Lenka ; Brožová, Věra (advisor) ; Mocná, Dagmar (referee)
The thesis is focused on the genre o f literature for girls. It examines how the dictate of beauty is reflected in the novels for girls and what changes were made in this matter during the last fifty years. The thesis gives an overview of topics that appear regularly in novels, of the thematic development of the genre and of the changes that occurred during the last five decades. A significant part is devoted to a character, its composition and transformation, as well as to the effect of beauty, which is reflected in how the character is perceived. The thesis is completed by an analysis of the display of beauty in specific works of A. Santarová, I. Hercíková, S. Rudolf and L. Lanczová. In order to illustrate the current average reader o f this literature genre for girls, the analysis of a questionnaire submitted at a secondary school, a high school and at the forum of Lenka Lanczová's website is added.
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SPARK PLASMA SINTERING OF BALL MILLED AND ATOMIZED POWDER BASED ON Fe-Al
Šíma, V. ; Minárik, P. ; Chráska, Tomáš
High-quality compacts were prepared using the spark plasma sintering (SPS) method from powders of similar composition Fe-Al-Zr-B. The properties of the sintered compacts are strongly dependent on the morphology and properties of the feedstock powder. The first powder was obtained by ball milling of the as cast alloy and the second was prepared by atomization under argon atmosphere. The morphology and structure of the two powders are compared and mechanical properties and microstructure of compacts prepared under the same conditions of the SPS procedure are discussed. The milled powder has an irregular morphology and shape of the polycrystalline particles, which have a completely disordered BCC structure with considerable internal stresses, high concentration of structural defects and the presence of aluminum oxide. The atomized powder particles are nearly spherical, polycrystalline with ordered B2 structure, with no significant signs of internal stresses and oxidation. Microhardness of particles of both powders was measured and compared with the microhardness of compact materials, the results of compression tests of compacts at room temperature were compared and discussed.
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Testing of composite hypotheses in regression models with small sample size
Simerská, Olga ; Hlávka, Zdeněk (referee) ; Kulich, Michal (advisor)
The thesis, through a simulation study, examines the behaviour of asymptotic tests for testing hypotheses that several coefficients in logistic models are zero. Likelihood ratio, Wald's, and Rao's tests are considered. The necessary theory is formulated to derive the form of the statistics of asymptotic tests for testing composite hypotheses in logistic regression. Based on the numerical treatment of simulated data, the levels of significance of these tests are investigated, with critical values of the chi-squared distribution. The powers of the tests are then compared, modified empirically so that all tests reject the null hypotesis at the 5% level. The main focus is on the dependence of these values on the sample size and parameter settings.
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Formulation of extemporaneous paediatric liquid preparations in the hospital pharmacy
Klovrzová, Sylva ; Šklubalová, Zdeňka (advisor) ; Dittrich, Milan (referee) ; Masteiková, Ruta (referee)
Charles University in Prague, Faculty of Pharmacy in Hradci Králové Department of: Pharmaceutical Technology Candidate PharmDr. Sylva Klovrzová Supervisor doc. PharmDr. Zdeňka Šklubalová, Ph.D. Title of Doctoral Thesis: Formulation of extemporaneous paediatric liquid preparations in the hospital pharmacy In the paediatric population, oral solutions and/or suspensions represent a suitable alternative to preparation of hard capsules in the pharmacy. This thesis aims at formulation of stable liquid oral preparations with cardiologic drugs, propranol- hydrochloride, sotalol-hydrochloride and furosemide, for the children aged from newborn to approximately 6 year. At the formulation of the preparation compositions, the simple routine preparation in a pharmacy was the main target as well as the use of excipients safe for paediatric population in the minimal necessary amount. Using a high performance liquid chromatography, chemical stability of the active ingredient and, simultaneously, the preservative was determined in all formulated preparations stored at two different temperatures at time points over minimum 180 days. In order to achieve this, the specific analytical methods were developed and validated at the department of Analytical chemistry, Faculty of Pharmacy in Hradec Králové. However, the...
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