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Geological and gravimetric pattern of the Ethiopia
Kuznetsova, Alevtina ; Valenta, Jan (advisor) ; Martínek, Karel (referee)
From a geological point of view, Ethiopia is a unique country where active tectonics displays can be studied, in the context of extensive East African Rift System (EARS) evolution, where the Main Ethiopian Rift (MER) is a part. The Main Ethiopian Rift (MER) is typical continental rift structure spread between the African, Somali, and Arabian lithospheric plates stretching over 6,000 kilometres from Syria to central Mozambique. This study of the gravity pattern in Ethiopia reveals significant crustal thinning in the Main Ethiopian Rift and Northern Afar regions. In the southern Afar, the earth's crust has a slightly higher thickness and, moreover, probably contains a significant proportion of the continental crust. The understanding of crustal thinning in the context of active rifting is essential to predict future geodynamic events in that region, which is crucial for the sustainable life of a rapidly expanding population and the necessary construction of infrastructure. This work provides an analysis and re-interpretation of archival gravity data collected from land surface surveys and airborne gravity studies (archive of Geological Survey of Ethiopia) in conjunction with available geological and structural data to evaluate overall gravimetric pattern of Ethiopia and determine main geological...
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Photoluminescence spectroscopy of nanomaterials
Dzian, Jan ; Soubusta, Jan (advisor) ; Valenta, Jan (referee)
Photoluminescence (PL) is being used as non-destructive measurement of optical properties of solids. Amongst measured properties is particularly structure of energetical levels of materials, but we can also deduce structure of material or its additives. In theoretical part of this thesis we deal with theory of photoluminescence and photoluminescence spectroscopy, followed by sections dedicated to carbon nanodots, semiconductor core-shell nanodots, nanodots of transition metal dichalcogenides and bulk crystal of ReS2 . In experimental section we describe devices and setups used for measuring spectra of photoluminescence, followed by descriptions of measured samples. In section of results we show measured PL spectra of samples and PL spectra depending on various parameters, e.g. excitation wavelength or sample concentration. These spectra are subsequently interpreted and based on them are deduced the properties of samples.
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Geophysical and gravimetric pattern of Ethiopia, construction, and verification of a new gravity map of Ethiopia
Kuznetsova, Alevtina ; Valenta, Jan (advisor) ; Martínek, Karel (referee)
From a geological point of view, Ethiopia is a unique country where active tectonics displays can be studied, in the context of extensive East African Rift System (EARS) evolution, where the Main Ethiopian Rift (MER) is a part. The Main Ethiopian Rift (MER) is typical continental rift structure spread between the African, Somali, and Arabian lithospheric plates stretching over 6,000 kilometres from Syria to central Mozambique. This study of the gravity pattern in Ethiopia reveals significant crustal thinning in the Main Ethiopian Rift and Northern Afar regions. In the southern Afar, the earth's crust has a slightly higher thickness and, moreover, probably contains a significant proportion of the continental crust. The understanding of crustal thinning in the context of active rifting is essential to predict future geodynamic events in that region, which is crucial for the sustainable life of a rapidly expanding population and the necessary construction of infrastructure. This work provides an analysis and re-interpretation of archival gravity data collected from land surface surveys and airborne gravity studies (archive of Geological Survey of Ethiopia) in conjunction with available geological and structural data to evaluate overall gravimetric pattern of Ethiopia and determine main geological...
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Optimization of high-pressure experiments for measurement of optical activity
Plamitzer, Luboš ; Valenta, Jan (advisor) ; Baumruk, Vladimír (referee)
The presented bachelor thesis focuses on the effects of high hydrostatic pressure on Raman spectra of selected monoterpenes: (−)-fenchone, (−)-carvone, (−)-limonene and (−)-α-pinene. The spectra under pressures up to 13 GPa were obtained using a diamond anvil cell. All compounds show a significant shift of vibration peak maxima and a change of their intensity. In the case of (−)-fenchone and (−)-α-pinene an "anomalous" decrease of vibrational frequency with increasing pressure was observed, which for (−)-fenchone corresponds to available results of high pressure experiments on structurally similar cam- phor. Pressure-induced spectral and structural changes were also modelled using both classical and quantum-mechanical simulation methods. 1
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Volcanic rocks and possibilities of their research using geophysical methods
Votrubcová, Kristýna ; Valenta, Jan (advisor) ; Vlček, Josef (referee)
5 Abstrakt (EN) The research focuses on the application of geophysical methods and subsequent data processing for the prospecting of igneous rocks and the search for volcanic structures. The literature review summarizes the physical and petrological foundations of various physical methods that can be utilized in the search for volcanic rocks, and discusses their most appropriate uses. The greatest emphasis is placed on the method of magnetometry, which is significant in identifying volcanoes. The work also explores the use of geoelectrical and seismic methods, radiometry, and gravimetry. In the practical section, geophysical measurements were conducted in the field to map the extent of the Tertiary volcano and other geological structures in the Elbe Sandstone Mountains. The extent of the volcanic body was successfully mapped using magnetic measurements. The results of the measured Electrical Resistivity Tomography (ERT) profile corresponded to the extent of the volcanite body and showed that the body was significantly fractured. Other findings include the mapping of a fault zone, to which the volcanic body ascend could be linked, and the mapping of another fault zone in a nearby valley, which is assumed to have a fault character. Key words: igneous rocks, volcanism, geophysics, magnetometry, VLF, ERT
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Geophysical prospection of Early Medieval settlements
Marešová, Barbora ; Valenta, Jan (advisor) ; Vošvrdová, Eliška (referee)
This bachelor thesis focuses on geophysical prospecting within non-destructive archaeology. To successfully carry out a geophysical survey on an archaeological site, it is important to understand the physical principles of the methods used as well as the history and characteristics of the site. This thesis aims to provide a comprehensive overview of this problem. The literature review begins with an explanation of the physical parameters that form the basis of geophysical prospecting, followed by an overview of the methods used for geophysical surveys. Finally, a practical example of geophysical prospecting is presented on the Praha-Královice site. The methodology, data processing, and interpretation of the results are also described in detail. The exploratory part of the thesis discusses how this prospecting led to the discovery of new information about the site, including the position and size of the medieval rectory. Additionally, this thesis provides a comparison of this prospecting with other published geophysical surveys of archaeological sites. Key words: geophysics, electromagnetic induction measurements, GPR, early Middle Ages, archaeology, Praha-Královice, rectory
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First Aid in Secondary Education
Valenta, Jan ; Malá, Michaela (advisor) ; Prokešová, Eva (referee)
Title: First Aid in Secondary Education Objectives: The aim of the thesis is to compare the knowledge of first aid students of selected secondary schools in Karlovy Vary and their possible relationship to the number of teaching hours with the topic of first aid and the teaching methods used. Methods: In our theoretical-research thesis we used the method of analysis and the method of comparison. Available school documents, data obtained during testing of pupils' knowledge and data obtained by means of a survey from teachers were analyzed. Data collection took place using a test and a survey. A comparison of the data followed. The research group consisted of 82 students and 4 teachers from 4 selected secondary schools in Karlovy Vary. Results: We found minimal differences in first aid knowledge among students of selected secondary schools in Karlovy Vary. We did not find a direct link between students' knowledge and the number of first aid lessons and teaching methods used. Keywords: High School, School Legislation, Teaching Methods, Life Threatening Conditions, Framework Education Programme, School Education Programme
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Cutting equipment
Valenta, Jan ; Dokoupil, Vladimír (referee) ; Omes, Jiří (advisor)
The subject of this thesis is to desing a cutting equipment for cutting wires from wire mesh. In theoretical part the cutting proces and elements which appear in the proces are described. In the practical part these finding are used to create a design of cutting equipment. As part of design development, selected components are described and the stress of these components is determined.
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Imaging of fluorescently labelled mitochondria using Biplane_FPALM microscopy
Dostál, Marek ; Plášek, Jaromír (advisor) ; Valenta, Jan (referee)
Title: Imaging of fluorescently labelled mitochondria using Biplane FPALM microscopy Author: Bc. Marek Dostál Department: Fyzikální ústav UK Supervisor: prof. RNDr. Jaromír Plášek, CSc. Consultants: RNDr. Petr Ježek, DrSc. Mgr. Hana Engstová, Ph.D. Abstract: In this thesis the results are presented of a search for suitable PCFP markers for a visualization inner and outer mitochondrial membranes by unique biplane FPALM microscope. We participated in debugging the measuring software for the purpose of 3D vizualization mitochondrial nets and determine their parameters. For this purpose were developed two methods. The first one can be applied to determine the parametrs of outer membranes and the second one is applicable to determine parametrs of inner membranes. On smaller statistical file we managed to confirm dependence quality of mitochondrial net on the cell culture conditions. Under stress conditions e.g. hypoxia the quality of mitochondrial net is changed. Keywords: mitochondria, Biplane FPALM, GFP, 3D visualization.
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