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Fusion systems and their shielding
Roubal, Michal ; Katovský, Karel (referee) ; Král, Dušan (advisor)
This thesis is concerned with nuclear fusion and its use as a source of energy for humanity. In the first part of my thesis, I will briefly explore the research history of nuclear fusion. Next, I will investigate the various possible issues connected with achieving and sustaining nuclear fusion. I will briefly discuss the importance of mastering it. I will talk about existing and anticipated risks of radiation damage which can occur during nuclear fusion. Lastly, i will discuss the principles of tritium breeding.
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Isotopic characterization of selected fruit juices - determination of authenticity on the basis of deuterium content by SNIF-NMR
Vyčítalová, Lucie ; Kolář, Kamil (referee) ; Sečkářová,, Pavlína (advisor)
The deuterium content of sugar in fruits is influenced mainly by two factors – the botanical and also the geographical origin of the fruit. The information of the fruit origin is kept even after fermentation of the sugar, in the molecules of ethanol. The deuterium content on the methyl group of ethanol then varies depending upon the botanical origin of the fruit. SNIF-NMR (Site-specific Natural Isotope Fractionation – Nuclear Magnetic Resonance) is a specific method for determination of the deuterium isotopic ratio (D/H) in small molecules, e.g. ethanol. This isotopic technique is widely used for determination of sugar adulteration of fruit-based beverages (wines, fruit juices..). In this thesis, the authentic samples of five different fruits (apples, oranges, grapefruits, pineapples and grapes) available in the Czech market have been collected and analyzed by SNIF-NMR. The results are presented as well as the comparison to some commercially available fruit juices and nectars.
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Low Energy Nuclear Reactions
Paták, Roman ; Kaplan, Zdeněk (referee) ; Píštěk, Václav (advisor)
This bachelor thesis deals with collection and arrangement of information about cold fusion. The introduction describes discovery of the cold fusion, problems associated with it and the response of the scientific community. Furthermore, there are explained the assumed basic conditions of its emergence and some of the experiments are detailly described. Finally, the possible direction of the cold fusion utilization in the future is easily outlined.
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Synthesis of modified and labeled acylceramides
Havrišák, Tomáš ; Opálka, Lukáš (advisor) ; Pour, Milan (referee)
Charles University Faculty of Pharmacy in Hradec Králové Department of Organic and Bioorganic Chemistry Candidate: Tomáš Havrišák Supervisor: PharmDr. Lukáš Opálka, Ph.D Title of diploma thesis: Synthesis of modified and labeled acylceramides Upper most layer of skin, stratum corneum is providing effective barrier which protects us from impact of environment. Extracellular lipids of stratum corneum are mostly composed of ceramides, free atty acids and cholesterol. Earlier it was suggested that these lipids are highly rigid, which enables sufficient barrier function. But presently, it is known that some structural parts of these lipids are more fluid. So far, ultralong ceramides (also known as acylceramides), lipids which are necessary for correct barrier function still remain partly unexplored. Mobility of sphingosine part and linoleic ester have already been studied, but mobility of the ultralong chain is speculative. Obtaining information about mobility of particular parts of acylceramides is difficult because of their unavailability with required labelling. Our aim was to prepare acylceramides with deuterium-labelled half of their ultralong chain between carbons C17 - C32 from commercially available perdeuterated compounds. From available options we chose 1,12-dibromodocecane and...
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Vibrational modes of nucleic acids components characterized by means of variable proton-deuterium exchange
Zoul, David ; Štěpánek, Josef (advisor) ; Šloufová, Ivana (referee)
Although the nucleon acid oscillatory spectra have been studied for a long period of time, many of oscillating modes have not been properly explained regarding their geometric sensitivity and weak binding. One of the possibilities how to acquire experimental data for interpretation of theese modes is to confront oscillating spectra of isotopes. The simplest is proton - deutron exchange. When molecules dissolve in heavy water they rapidly exchange the heteroatoms, but this is simultaneous for more stages, which leads to dynamic equilibrium state among various isotope forms. Statistic analysis of temporal progression of Raman spectra give us the possibility to analyze the spectra and to obtain unique experimental data. This technique is very promising for more complex nucleon acid segments to gain more structural information. This diploma thesis represents pilot study of introduced methodics. The objective is to implement adaptation of Raman spectrometr for given types of expiments and undertake first series of measurements. The results should clarify application bounds of proposed method refering to sensitivity, time constant of incident isotope exchange, severity of read-out in comparasion of achieved accuracy of the measurement.
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Snowmelt runoff during rain-on-snow events in the Ptačí brook basin calculated using stable water isotopes
Valdhansová, Klára ; Jeníček, Michal (advisor) ; Šípek, Václav (referee)
Rain-on-snow events represent one of the basic mechanisms causing floods. Rain falling on the snow cover causes enhanced melting and the resulting runoff often exceeds the runoff caused by rain. During the winter seasons 2018 and 2019, water samples from the stream, snowpack and precipitation were repeatedly taken in the the Ptačí Brook catchment in the Šumava mountains, and the concentrations of 2 H and 18 O were measured in the laboratory. Based on the observed isotope ratios 18 O/16 O and 2 H/1 H in combination with other variables measured in the catchment, the two ROS events from 2019 were reconstructed. The ratio of heavy isotopes increased in the snowpack due to ROS events. Using the end member mixing equation, a hydrograph separation was performed for both investigated events. For the first event, it was not possible to clearly separate groundwater from rainfall, and thus the range of snow in the total runoff was determined by its separation from rainfall and subsequent separation from groundwater. The second event examined was separated directly into three components: rainfall, groundwater and snow. According to the analyses, the total runoff during ROS events in both cases was mostly formed by event water (a combination of rainfall and melt water). The melting water from the snow cover...
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Fusion systems and their shielding
Roubal, Michal ; Katovský, Karel (referee) ; Král, Dušan (advisor)
This thesis is concerned with nuclear fusion and its use as a source of energy for humanity. In the first part of my thesis, I will briefly explore the research history of nuclear fusion. Next, I will investigate the various possible issues connected with achieving and sustaining nuclear fusion. I will briefly discuss the importance of mastering it. I will talk about existing and anticipated risks of radiation damage which can occur during nuclear fusion. Lastly, i will discuss the principles of tritium breeding.
|
|
|
Low Energy Nuclear Reactions
Paták, Roman ; Kaplan, Zdeněk (referee) ; Píštěk, Václav (advisor)
This bachelor thesis deals with collection and arrangement of information about cold fusion. The introduction describes discovery of the cold fusion, problems associated with it and the response of the scientific community. Furthermore, there are explained the assumed basic conditions of its emergence and some of the experiments are detailly described. Finally, the possible direction of the cold fusion utilization in the future is easily outlined.
|
|
|
Vibrational modes of nucleic acids components characterized by means of variable proton-deuterium exchange
Zoul, David ; Štěpánek, Josef (advisor) ; Šloufová, Ivana (referee)
Although the nucleon acid oscillatory spectra have been studied for a long period of time, many of oscillating modes have not been properly explained regarding their geometric sensitivity and weak binding. One of the possibilities how to acquire experimental data for interpretation of theese modes is to confront oscillating spectra of isotopes. The simplest is proton - deutron exchange. When molecules dissolve in heavy water they rapidly exchange the heteroatoms, but this is simultaneous for more stages, which leads to dynamic equilibrium state among various isotope forms. Statistic analysis of temporal progression of Raman spectra give us the possibility to analyze the spectra and to obtain unique experimental data. This technique is very promising for more complex nucleon acid segments to gain more structural information. This diploma thesis represents pilot study of introduced methodics. The objective is to implement adaptation of Raman spectrometr for given types of expiments and undertake first series of measurements. The results should clarify application bounds of proposed method refering to sensitivity, time constant of incident isotope exchange, severity of read-out in comparasion of achieved accuracy of the measurement.
|
|
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Isotopic characterization of selected fruit juices - determination of authenticity on the basis of deuterium content by SNIF-NMR
Vyčítalová, Lucie ; Kolář, Kamil (referee) ; Sečkářová,, Pavlína (advisor)
The deuterium content of sugar in fruits is influenced mainly by two factors – the botanical and also the geographical origin of the fruit. The information of the fruit origin is kept even after fermentation of the sugar, in the molecules of ethanol. The deuterium content on the methyl group of ethanol then varies depending upon the botanical origin of the fruit. SNIF-NMR (Site-specific Natural Isotope Fractionation – Nuclear Magnetic Resonance) is a specific method for determination of the deuterium isotopic ratio (D/H) in small molecules, e.g. ethanol. This isotopic technique is widely used for determination of sugar adulteration of fruit-based beverages (wines, fruit juices..). In this thesis, the authentic samples of five different fruits (apples, oranges, grapefruits, pineapples and grapes) available in the Czech market have been collected and analyzed by SNIF-NMR. The results are presented as well as the comparison to some commercially available fruit juices and nectars.
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