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Low pressure plasma application for the surface cleaning of archaeological objects
Bubnová, Kateřina ; Grossmannová, Hana (referee) ; Krčma, František (advisor)
This diploma thesis builds on my bachelor thesis, which was focused on the application of low-pressure hydrogen plasma and argon-hydrogen plasma on layers of corrosion products. According to results of the experiments, an appropriate temperature for plasma chemical treatment of lead samples was detected. However, the process of corrosion removal through plasma chemical treatment needs to be further optimized to prevent potential damage to the original historical artefacts. Optimization of the treatment process is therefore the main subject of this work’s research. The model samples with artificial corrosion layers with dual composition were prepared. These samples were put to desiccator with sand and organic acid. The samples corroded in environment of acetic acid or formic acid with the aim of creating the corrosion, which would be at least partially simulated with corrosion on the original artefacts. The process of corrosion lasted for eleven months. After that, the samples were dried out under reduced pressure, put to the protecting foil with humid and oxygen absorbers. In contrast with my bachelor thesis where the continuous regime was chosen for the treatment, the pulse regime with three different condition settings is used. Process of experiment was monitored by OES, surface of samples was analyzed by SEM, EDX, XRD methods. Results from experiments with model samples were used for treatment of original artefacts with missing documentation, so their eventual damaging was acceptable.
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Plasma cleaning of corroded plumb objects
Bubnová, Kateřina ; Grossmannová, Hana (referee) ; Krčma, František (advisor)
This bachelor thesis deals with the application of low-pressure hydrogen plasma to lead corrosion products. There are many historical objects and these objects require careful removal of corrosion layers. Therefore, it is necessary to optimize the treatment process in order not to destroy real historical artefacts in the future. This work is focused on lead, which has not been explored by this method yet. Model samples with corrosion were prepared for comparison and these samples corrode in vapors of concentrated acetic acid and formic acid. There were three working temperatures for plasma chemical treatment because of the low lead melting point and the atomic heating. Argon-hydrogen plasma and hydrogen plasma was applied to 12 corroded samples during the experiment. Process progress was monitored by optical emission spectrometry and surface analysis was performed by SEM, XRD and EDX analysis. The results of these analyzes showed that the most appropriate temperature for plasma chemical treatment was 130 ° C. Based on the obtained results many suggesstions and ideas were obtained for the future research like using of pulse mode and gas composition.
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Low pressure plasma application for the surface cleaning of archaeological objects
Bubnová, Kateřina ; Grossmannová, Hana (referee) ; Krčma, František (advisor)
This diploma thesis builds on my bachelor thesis, which was focused on the application of low-pressure hydrogen plasma and argon-hydrogen plasma on layers of corrosion products. According to results of the experiments, an appropriate temperature for plasma chemical treatment of lead samples was detected. However, the process of corrosion removal through plasma chemical treatment needs to be further optimized to prevent potential damage to the original historical artefacts. Optimization of the treatment process is therefore the main subject of this work’s research. The model samples with artificial corrosion layers with dual composition were prepared. These samples were put to desiccator with sand and organic acid. The samples corroded in environment of acetic acid or formic acid with the aim of creating the corrosion, which would be at least partially simulated with corrosion on the original artefacts. The process of corrosion lasted for eleven months. After that, the samples were dried out under reduced pressure, put to the protecting foil with humid and oxygen absorbers. In contrast with my bachelor thesis where the continuous regime was chosen for the treatment, the pulse regime with three different condition settings is used. Process of experiment was monitored by OES, surface of samples was analyzed by SEM, EDX, XRD methods. Results from experiments with model samples were used for treatment of original artefacts with missing documentation, so their eventual damaging was acceptable.
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Associations as political actors in small municipalities? Case study of Brandýs nad Orlicí microregion
Bubnová, Kateřina ; Jüptner, Petr (advisor) ; Bubeníček, Václav (referee)
This diploma thesis aims to provide insight into the municipal system in small municipalities. The work consists of two parts, a literature search and a research analytical part. The subject of the research is a discussion of Czech and later also German authors who deal with communal politics. The subject of this work is the role of associations as political actors in small municipalities with less than 300 inhabitants. The results of the research demonstrate the identical and different features of the Czech and German debate regarding small municipalities and the involvement of associations in political life. As a result, several variables were identified that are repeated for the authors. The sample is 10 municipalities from the Brandýs nad Orlicí micro-region, which are compared with each other in several areas. Municipalities are very similar, especially in terms of population, and thus the sample is relevant for mutual comparison between municipalities. The subject of the research is the identification of federal candidates and representatives, the support of associations from the municipality and the motivation of federal candidates for candidacy. The key source is interviews with council members and federal candidates, which are processed in the form of graphs and tables. In conclusion,...
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Plasma cleaning of corroded plumb objects
Bubnová, Kateřina ; Grossmannová, Hana (referee) ; Krčma, František (advisor)
This bachelor thesis deals with the application of low-pressure hydrogen plasma to lead corrosion products. There are many historical objects and these objects require careful removal of corrosion layers. Therefore, it is necessary to optimize the treatment process in order not to destroy real historical artefacts in the future. This work is focused on lead, which has not been explored by this method yet. Model samples with corrosion were prepared for comparison and these samples corrode in vapors of concentrated acetic acid and formic acid. There were three working temperatures for plasma chemical treatment because of the low lead melting point and the atomic heating. Argon-hydrogen plasma and hydrogen plasma was applied to 12 corroded samples during the experiment. Process progress was monitored by optical emission spectrometry and surface analysis was performed by SEM, XRD and EDX analysis. The results of these analyzes showed that the most appropriate temperature for plasma chemical treatment was 130 ° C. Based on the obtained results many suggesstions and ideas were obtained for the future research like using of pulse mode and gas composition.
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World maritime shipping at the beginning of 21. Century
Bubnová, Kateřina ; Romancov, Michael (advisor) ; Kučerová, Irah (referee)
The bachelor thesis deals with the world's maritime trade at the beginning of the 21st century. This thesis deals with the development during the 19th and 20th centuries from the point of view of progress, which influenced the modernization and progress in this area, the 20th and 21st century from the economic point of view, how the volume of goods transported changed. Segmenting cargo vessels is another important chapter, splitting into groups and subgroups, allows a better view of types of merchant ships. It also examines international organizations that are very important for determining and adhering to the rules. The chapter on Maritime Policy deals with environmental policy, balancing the goals of sustainable development and economic objectives of countries. The second part of the chapter deals with the issue of maritime piracy, which greatly hinders maritime trade. It focuses more on Somali piracy, although it is not currently the main danger area, so it has its own specifics. The last part deals with the most important ports as the basic components of maritime trade. Navy trails are linked to the New Silk Road, a project of the People's Republic of China, which could change the sea routes, considering new ports.
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World maritime shipping at the beginning of 21. Century
Bubnová, Kateřina ; Romancov, Michael (advisor) ; Kučerová, Irah (referee)
The bachelor thesis deals with the world's maritime trade at the beginning of the 21st century. This thesis deals with the development during the 19th and 20th centuries from the point of view of progress, which influenced the modernization and progress in this area, the 20th and 21st century from the economic point of view, how the volume of goods transported changed. Segmenting cargo vessels is another important chapter, splitting into groups and subgroups, allows a better view of types of merchant ships. It also examines international organizations that are very important for determining and adhering to the rules. The chapter on Maritime Policy deals with environmental policy, balancing the goals of sustainable development and economic objectives of countries. The second part of the chapter deals with the issue of maritime piracy, which greatly hinders maritime trade. It focuses more on Somali piracy, although it is not currently the main danger area, so it has its own specifics. The last part deals with the most important ports as the basic components of maritime trade. Navy trails are linked to the New Silk Road, a project of the People's Republic of China, which could change the sea routes, considering new ports.
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