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Study of glyphosate degradation in water plasma application
Vašinková, Alena ; Vávrová, Milada (referee) ; Mravcová, Ludmila (advisor)
This work deals with the current problem of increasing concentrations of glyphosate in groundwater and wastewater due to insufficient efficiency of methods used in wastewater treatment. From this point of view effective removing of glyphosate from water have to be developed by new methods and technological processes. The methods used so far in wastewater treatment plants should be replaced or supplemented by advanced oxidation processes. The practical part of this work is devoted to glyphosate and its degradation in water by plasma. Samples were taken sequentially during plasma application and further evaluated by LC/MS selected as suitable analytical methods. The aim of this work was to determine the efficiency of plasma in water with admixture of glyphosate.
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Diagnostics of active particles generated by the interaction of plasma microwave discharge with liquids
Kovaříková, Kateřina ; Töröková, Lucie (referee) ; Kozáková, Zdenka (advisor)
The first part of this Bachelor’s thesis describes problems of electric discharges in gas and on a surface of water solutions. It focuses on the generation of the active particles that are generated during the discharge and their subsequent analysis by appropriate analytical methods. The second part focuses on identification of the active particles that are generated during the microwave discharge in gas phase and during the interaction with water solution surface. The aim is to determine the influence of experimental conditions on the information of the active particles, specifically the nitrates and nitrite ions.
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Use of liquid chromatography to analyze caffeine solutions exposed to plasma
Brabcová, Kristýna ; Řezáčová, Veronika (referee) ; Mravcová, Ludmila (advisor)
This thesis deals with the current problem of increasing concentration of caffeine in water that is connected with caffeine consumption among people. This problem is not that urgent becusase the concentration is not high and for human is not so harmful. The bigger populaton is, the more caffeine people consume and the amount of caffeine in wastewater rises. This fact could be considered as a future problem. An appropriate method effective for elimination of harmful substances are advanced oxidation processes (AOP). Theoretical part describes purine alkaloids with detail desctription of caffeine. Plasma was chosen as a method for caffeine degradation and there are some facts described. There is a chapter about appropriate analytical methods. The samples were picked after periodical time intervals. These samples were analyzed by UHPLC. The results were compared with study dealing with this theme.
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Diagnostics of plasma generated by electrical discharge in organic solutions
Adámková, Barbora ; Krčma, František (referee) ; Kozáková, Zdenka (advisor)
This work deals with electrical discharge in organic solutions. The theoretical part was focused on plasma discharge in liquids and also plasma diagnostics. In the experimental part the influence of experimental conditions on the ignition of the discharge in alcohols was observed. Especially, the polarity of the applied voltage, concentration and conductivity of the solution was studied. Moreover, the amount of generated hydrogen peroxide in the ethanol solutions as well as the electrolyte solution of two different conductivities was determined. The results compared the current-voltage characteristic curve during the stable discharge and the phases that preceded it. These phases were the creation of bubbles, occasional ignition and stable discharge. From the recorded average values of current and voltage, current-voltage characteristics were constructed. It was found, that the increasing conductivity of the solution leads to an earlier discharge. In case of negative polarity of the voltage input on the main electrode, there was an earlier discharge than in the positive polarity. Voltage value necessary for the discharge ignition was lower by several hundred volts in the negative polarity. For example, for a solution of 95 vol. % ethanol and conductivity of 200 S, the breakdown voltage for a positive polarity was determinated as 1650 V but at negative polarity this voltage was only 1250 V. Moreover the influence of ethanol concentration on the ignition of the discharge was found, but there was no significant effect. Amount of generated hydrogen peroxide grew linearly with time. In the electrolyte solution, hydrogen peroxide was formed significantly more in comparison to the ethanol solution.
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Study of plasma effects on quinine solutions
Procházková, Michaela ; Dzik, Petr (referee) ; Kozáková, Zdenka (advisor)
This diploma thesis focuses on quinine solutions and quality of these solutions after applying plasma discharge. These electric discharges can be used to destroy some substances from the water. The theoretical part is focused on description of electric discharges in liquids and on the properties of quinine. In the experimental part, the properties of quinine solutions containing different electrolytes were analysed by UV-VIS spectrophotometer and fluorescence spectroscopy. Two different types of configurations of plasma discharges in liquids were used. Solutions were compared on the base of different concentration of quinine, different electrolytes, different configurations of plasma discharges and pH values of the solutions. Furthermore, the experimental work focuses on quinine solutions with the sodium nitrate. The time instability of the solutions was analysed. Also, the influence of the solution age and different types of the plasma discharge on the excitation and emission spectra of quinine were investigated.
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Study of decontamination effects of plasma and plasma activated water
Kovaříková, Kateřina ; Krouská, Jitka (referee) ; Kozáková, Zdenka (advisor)
The theoretical part of this Diploma’s thesis describes the use of plasma in decontamination processes. The experimental part of the thesis focuses on the preparation and characterization of model samples of organic dyes by appropriate analytical methods. The model samples were treated by direct exposure to plasma or plasma activated water. For both treatments, two different plasma sources were used - a dielectric barrier discharge in an ozonizer with subsequent bubbling of its gaseous products into the solution, and a microwave plasma jet applied to the liquid surface. The aim of the work was to evaluate the decontamination rate of the samples and to compare the performance of the different systems.
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Use of liquid chromatography to analyze caffeine solutions exposed to plasma
Brabcová, Kristýna ; Řezáčová, Veronika (referee) ; Mravcová, Ludmila (advisor)
This thesis deals with the current problem of increasing concentration of caffeine in water that is connected with caffeine consumption among people. This problem is not that urgent becusase the concentration is not high and for human is not so harmful. The bigger populaton is, the more caffeine people consume and the amount of caffeine in wastewater rises. This fact could be considered as a future problem. An appropriate method effective for elimination of harmful substances are advanced oxidation processes (AOP). Theoretical part describes purine alkaloids with detail desctription of caffeine. Plasma was chosen as a method for caffeine degradation and there are some facts described. There is a chapter about appropriate analytical methods. The samples were picked after periodical time intervals. These samples were analyzed by UHPLC. The results were compared with study dealing with this theme.
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Diagnostics of active particles generated by the interaction of plasma microwave discharge with liquids
Kovaříková, Kateřina ; Töröková, Lucie (referee) ; Kozáková, Zdenka (advisor)
The first part of this Bachelor’s thesis describes problems of electric discharges in gas and on a surface of water solutions. It focuses on the generation of the active particles that are generated during the discharge and their subsequent analysis by appropriate analytical methods. The second part focuses on identification of the active particles that are generated during the microwave discharge in gas phase and during the interaction with water solution surface. The aim is to determine the influence of experimental conditions on the information of the active particles, specifically the nitrates and nitrite ions.
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Study of plasma effects on quinine solutions
Procházková, Michaela ; Dzik, Petr (referee) ; Kozáková, Zdenka (advisor)
This diploma thesis focuses on quinine solutions and quality of these solutions after applying plasma discharge. These electric discharges can be used to destroy some substances from the water. The theoretical part is focused on description of electric discharges in liquids and on the properties of quinine. In the experimental part, the properties of quinine solutions containing different electrolytes were analysed by UV-VIS spectrophotometer and fluorescence spectroscopy. Two different types of configurations of plasma discharges in liquids were used. Solutions were compared on the base of different concentration of quinine, different electrolytes, different configurations of plasma discharges and pH values of the solutions. Furthermore, the experimental work focuses on quinine solutions with the sodium nitrate. The time instability of the solutions was analysed. Also, the influence of the solution age and different types of the plasma discharge on the excitation and emission spectra of quinine were investigated.
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Study of glyphosate degradation in water plasma application
Vašinková, Alena ; Vávrová, Milada (referee) ; Mravcová, Ludmila (advisor)
This work deals with the current problem of increasing concentrations of glyphosate in groundwater and wastewater due to insufficient efficiency of methods used in wastewater treatment. From this point of view effective removing of glyphosate from water have to be developed by new methods and technological processes. The methods used so far in wastewater treatment plants should be replaced or supplemented by advanced oxidation processes. The practical part of this work is devoted to glyphosate and its degradation in water by plasma. Samples were taken sequentially during plasma application and further evaluated by LC/MS selected as suitable analytical methods. The aim of this work was to determine the efficiency of plasma in water with admixture of glyphosate.
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