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Development of voltammetric methods for detection of bile acids and their conjugates
Petráňová, Karolína ; Schwarzová, Karolina (advisor) ; Nesměrák, Karel (referee)
The aim of this thesis is to study the electrochemical properties of bile acids and their conjugates. Specifically, cholic acid, chenodeoxycholic acid, taurocholic acid, taurochenodeoxycholic acid, glycocholic acid, and glycochenodeoxycholic acid were studied. The measurements were carried out on a boron-doped diamond electrode in an environment of acetonitrile and perchloric acid, with a water content of 0.55% in the solution by method of cyclic voltammetry. In order for bile acids to be electrochemically active, they must first be dehydrated, which takes place in a reaction with perchloric acid. This reaction requires a relatively long time, so it was accelerated by heating the compounds. The goal of this work was to determine the conditions under which the dehydration products of bile acids can be detected. The water content that can be added to the solution after dehydration to keep the voltammetric signal stable was determined. Furthermore, it was found that the voltammetric determination can be carried out even at a pH that is not extremely acidic in which is the the dehydration carried out. Finally, calibration dependencies were compiled.
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Rybí společenstva toků VÚ Boletice
PETRÁŇOVÁ, Karolína
The aim of the thesis was to monitor a population status of fish communities in two water catchments in SAC Boletice. The monitoring was performed in 2021 in five localities in the Blanice river catchment and in five localities in the Křemžský stream sector. The fish was caught with a help of electric current in a 100m long fishing sector. After setting the basic ichthyologic characteristics and evaluation the condition and health condition, the fish was returned back to their original habitat. There were four kinds of fish obtained (European bullhead, river trout, common minnow and European perch) and one kind of lamprey (brook lamprey). The locality with the highest diversity was locality No.3 (the Blanice - 3rd locality). On the other hand, there was no fish obtained in locality No.7 (Chlumanský stream below the pond) and there was only European perch obtained in locality No.8 (Chlumanský stream above the pond). The discussion of this thesis is focused on the links between the characteristics of individual localities and fish species occurrence as well as on a comparison of the results of the monitored flows with those from the previous years. Also the authors, who performed a SAC Boletice monitoring in previous years, had similar conclusions.
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Analysis of fruits and vegetables extracts by atomic spectrometry methods
Petráňová, Karolína ; Hraníček, Jakub (advisor) ; Kozlík, Petr (referee)
EN The aim of this thesis was to determine selected elements - chromium, manganese, copper, iron and zinc - in fruit and vegetable extracts. The method used for measurement was atomic absorption spectrometry with flame atomization. First, the optimal conditions for the measurement were found. Then the basic characteristics of the determination of each element under optimal conditions were determined. The determined optimal conditions were used in the analysis of real samples of extracts. The samples were appropriately diluted before measurement. The content of all 4 selected elements was determined in all 36 extracts from fruits and vegetables. All results were provided with statistical evaluation.
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Waste management in Czech Republic
Petráňová, Karolina ; Grosz, Jan (advisor) ; Milan, Milan (referee)
This diploma thesis discusses issues of waste production and related issues of waste management in the Czech Republic. Wastes are generated almost every day as a result of the most of human activities. The main objectives of waste management policy are the effort to regulate the amount of produced waste, increase the utilization of waste instead of its disposal and especially eliminate the negative impacts on the environment, natural resources and human health. These objectives are enforced especially through legislative instruments. Theoretical part of this thesis is a comparison of findings and knowledge gained by the studying of literature and other relevant sources from the area of production and management of wastes. The practical part of this thesis deals with the analysis of waste production and waste management in the Czech Republic in selected time frame and includes a prognosis of future development. The basis of the practical part are statistical data, processed with chosen statistic methods, especially with the analysis of time series. Finally, a survey about the waste management is carried out with the aim of finding the current state in the field of waste sorting.
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