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Preparation of Ag/Co/Ag Trilayers
Burda, Pavel ; Kolíbal, Miroslav (referee) ; Čechal, Jan (advisor)
The Bachelor's thesis is aimed to the preparation of silver and cobalt ultrathin films. The films are formed on modified surfaces of crystalline silicon substrates (SiO2/Si(111), Si(111) ?H, Si(111) 7×7) and amorphous SiO2 in a form of a quartz glass. Thin films are grown using an effusion cell for Molecular Beam Epitaxy (MBE). Surface modified surfaces are covered subsequently by a silver, cobalt and silver thin layer. The individual film thickness is 6 nm. Consequently the samples are studied by the X-ray Photoelectron Spectroscopy (XPS) and the Atomic Force Microscopy (AFM). The morphology of thin films and growth modes are compared among the substrates. Growth modes change with the surface modification type. Complete trilayer system Ag/Co/Ag was prepared on SiO2/Si(111) and Si(111) 7×7. Such system can be employed in plasmonics in order to allow the control of surface plasmon polariton properties by an external magnetic field.
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The content and binding of silver in galena
Němec, Matěj ; Goliáš, Viktor (advisor) ; Zachariáš, Jiří (referee)
Galena as the most important silverbearing ore is found in almost every Ag deposit. If the content of Ag is higher than 0,5 wt. % then is called galena solid solution - PbSss. The galena Ag has two forms of occurrence - inclusions and isomorphic silver. Aboat ninety percent of galena Ag is product of retrograde proces of PbSss cooling. These are matildite (AgBiS2), miargyrite (AgSbS2), diaforite (PbAg3Sb3S8), freislebenite (AgPbSbS3), pyrargyrite (Ag3SbS3) aramayoite (Ag(Sb,Bi)S2), freibergite (Ag12Sb4S13), gustavite (AgPbBi3S6) etc. The smaller amounth of isomorphic Ag is substituted as 2Ag+ = PbII+ . Under the usual conditions of deposition (200 - 300řC) , the solubility of Ag2S is to low. The content of Ag in galena under these conditions is not higher then 0,4 mol. % at 615řC. Most of the isomorphic Ag is bound in coupled substitution Ag+ + Bi III+ /Sb III+ = 2 PbII+ . In this case the content of Ag in PbS can be as high as 9 wt. % at 350 - 400řC. At the deposites where wasn't activated this Bi/Sb - Pb coupled substitution the content of Ag in galena is very low. The content of trace elements of Ag, Bi and Sb can also influence the galena crystal habit. Galena rich on Bi ususaly creates octahedral crystals. Galena with a higher content of Ag and Sb usualy creates cubic crystals.
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The use of BEAS-2B cell line for micronucleus assay in genetic toxicology
Červená, Tereza ; Rössner, Pavel (advisor) ; Rubeš, Jiří (referee)
This thesis deals with the application of BEAS-2B cell line for micronucleus assay in genetic toxicology. It is divided into two main parts: a) theoretical introduction to the analysis and search for suitable models for testing the impact of air pollution and manufactured nanoparticles, b) practical part that describes the results of micronuclei induction by polycyclic aromatic hydrocarbons (PAHs), extractable organic matter (EOM) from diesel exhaust particles obtained from emissions of three types of fuel and engineered nanoparticles. BEAS-2B cell line is a nonmalignant human model of lung epithelium which seems to be suitable for micronucleus assay. This assay is commonly used for determining the genotoxicity of various substances to wide variety of cell cultures and also in human studies. In this thesis, the following substances were tested: benzo[a]pyrene, 3-nitrobenzanthrone and 1-nitropyrene as carcinogenic PAHs commonly found in polluted air; EOMs from exhaust particles of 100 % diesel fuel, a blend of diesel fuel and 30 % of biodiesel, 100 % biodiesel and two types of engineered nanoparticles (TiO2 and Ag). The cells were treated with the compounds for 28, 48 and 72 hours. The results confirm the suitability of BEAS-2B cell line as a model for testing the genotoxicity of substances under...
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Electronics and adsorption properties of model catalytic systems contains cerium
Cabala, Miloš ; Veltruská, Kateřina (advisor) ; Jiříček, Petr (referee) ; Polčík, Martin (referee)
Title: Electronics and adsorption properties of model catalytic systems contains cerium Author: Miloš Cabala Department: Department of Surface and Plasma Science, Supervisor: RNDr. Kateřina Veltruská, Department of Surface and Plasma Science, Abstract: The doctoral thesis contains the study of model catalyst systems based on cerium and ceria. The thesis deals with model systems of CeAg, CeO2/Cu(111), Ni- CeO2/Cu(111) a Ni-Sn-CeO2/Cu(111). We have studied these systems using photoelectron spectroscopy, ion scattering spectroscopy and low energy electron diffraction. Model systems were prepared under strictly defined conditions. The strong bimetallic interaction was observed on the CeAg layers. Molecular adsorption of carbon monoxide on CeAg was demonstrated. We also observed intensive reaction of these layers with oxygen. By measurements in different directions of surface Brillouin zone, we managed to reconstruct the band structure of the prepared CeO2/Cu(111) layer. We have shown that the Cu substrate interacts weakly with deposited CeO2 layer. This interaction results in a charge transfer from Cu into CeO2. Overall, in the valence spectrum we have identified three main electron bands corresponding to O 2p state bound in CeO2. It has been proven that the deposition of Ni on CeO2 layers leads to partial...
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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.
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The content and binding of silver in galena
Němec, Matěj ; Goliáš, Viktor (advisor) ; Zachariáš, Jiří (referee)
Galena as the most important silverbearing ore is found in almost every Ag deposit. If the content of Ag is higher than 0,5 wt. % then is called galena solid solution - PbSss. The galena Ag has two forms of occurrence - inclusions and isomorphic silver. Aboat ninety percent of galena Ag is product of retrograde proces of PbSss cooling. These are matildite (AgBiS2), miargyrite (AgSbS2), diaforite (PbAg3Sb3S8), freislebenite (AgPbSbS3), pyrargyrite (Ag3SbS3) aramayoite (Ag(Sb,Bi)S2), freibergite (Ag12Sb4S13), gustavite (AgPbBi3S6) etc. The smaller amounth of isomorphic Ag is substituted as 2Ag+ = PbII+ . Under the usual conditions of deposition (200 - 300řC) , the solubility of Ag2S is to low. The content of Ag in galena under these conditions is not higher then 0,4 mol. % at 615řC. Most of the isomorphic Ag is bound in coupled substitution Ag+ + Bi III+ /Sb III+ = 2 PbII+ . In this case the content of Ag in PbS can be as high as 9 wt. % at 350 - 400řC. At the deposites where wasn't activated this Bi/Sb - Pb coupled substitution the content of Ag in galena is very low. The content of trace elements of Ag, Bi and Sb can also influence the galena crystal habit. Galena rich on Bi ususaly creates octahedral crystals. Galena with a higher content of Ag and Sb usualy creates cubic crystals.
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Preparation of Ag/Co/Ag Trilayers
Burda, Pavel ; Kolíbal, Miroslav (referee) ; Čechal, Jan (advisor)
The Bachelor's thesis is aimed to the preparation of silver and cobalt ultrathin films. The films are formed on modified surfaces of crystalline silicon substrates (SiO2/Si(111), Si(111) ?H, Si(111) 7×7) and amorphous SiO2 in a form of a quartz glass. Thin films are grown using an effusion cell for Molecular Beam Epitaxy (MBE). Surface modified surfaces are covered subsequently by a silver, cobalt and silver thin layer. The individual film thickness is 6 nm. Consequently the samples are studied by the X-ray Photoelectron Spectroscopy (XPS) and the Atomic Force Microscopy (AFM). The morphology of thin films and growth modes are compared among the substrates. Growth modes change with the surface modification type. Complete trilayer system Ag/Co/Ag was prepared on SiO2/Si(111) and Si(111) 7×7. Such system can be employed in plasmonics in order to allow the control of surface plasmon polariton properties by an external magnetic field.
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