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Oxalates in rocks and plants
Novotná, Julie ; Jehlička, Jan (advisor) ; Hruška, Jakub (referee)
SUMMARY: The presence of oxalates is widespread not only as kidney stones, but in whole nature. It is well known that oxalates are products of some plants, fungi and lichens. The accumulates of calcium oxalates are increased in: sorrel, rhubarb, spinach, soya, dieffenbachia, etc. Oxalates serve many important functions in plants such as calcium regulation, protection from herbivory and metal detoxification. Aluminum detoxification is ability of plants, which is critical factor for crop production. Breeding of commercially viable low oxalate cultivars or genetic manipulation with crops should deal to enhance of nutritional quality and enhance of agricultural production too. The presentation of oxalates in rocks is well representing by calcium oxalate minerals, whewellite and weddellite. Minerals occur in sediments into precipitated forms within concretions and hydrothermal veins or dispersed form into modern sediments, e.g. peats. Oxalates are biologic products, therefore they can indicate biological activities, so oxalates should be sought for researching on cosmic objects. The observation of oxalates on Earth and interpretation of the Raman spectra is necessary in these types of study.
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Use of handheld Raman spectrometers for identification of secondary minerals in situ
Kdýr, Šimon ; Jehlička, Jan (advisor) ; Culka, Adam (referee)
Summary: The sulfates are secondary minerals, that are occurring in the different terrestrial conditions. Their study is useful for understanding of the processes, that are leading to occurence the acid mine drainage. Next sphere of research is out of our globe (it means Mars). The Raman spectroscopy is nondestructive analytical method, that it is advantage of this method. It has occured great development on the field of miniaturisation in a few last years. It is opportunity for aplication out of laboratory and it is possible to make a study in field conditions. At the introduction, this work is occupied with instrumentations, advantages and disadvantages of the use mobile Raman spectrometers. You find there summarises publications, that are occupied with mineralogy, origin of sulfates and opportunities of application mobile Raman spectrometers for their study. At the end of the recherche, it shows some particular localities, where it could be applicable for study sulfates by Raman spectroscopy and where mobile Raman spectrometers were used for identification of sulfate minerals.
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Raman spectrometry of carotenoids of selected microorganisms
Novotná, Julie ; Jehlička, Jan (advisor) ; Machovič, Vladimír (referee)
In this thesis Raman spectroscopy is evaluated as a tool of identification and discrimination of carotenoids from microbial biomass. Microorganisms, halophilic or nonhalophilic, belong to Cyanobacteria, Proteobacteria, Chlorophyta, Rhodophyta and to others. Biomass was cultiveted under laboratory conditions and yielded varied colours. Raman spectra were recorded succesfully from lyophilized biomass by excitation wavelenth 514.5 nm (dispersive Raman microspectrometr) and 1064 nm (FT Raman spectrometer). Results were compared with Raman spectroscopic data from pigment extracts. Spectra of carotenoids are characterized by the main Raman bands υ1, υ2 a υ3 due to C=C stretching, C-C stretching and C-CH3 deformation. HPLC/UV-VIS allows effective pigment separation from extracts and detection of separated pigments by UV-VIS analyzator. Assessment of Raman analysis and its potential to detect microbial carotenoids are discused. Sarcinaxantin is an unusual carotenoid identified together with more common β - carotene. Raman spectroscopic results obtained on carotenoids recorded from colonies which accumulated more than one carotenoid need to be interpreted carefully. Powered by TCPDF (www.tcpdf.org)
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Current exobiology missions to Mars. Importance for geoscience and search of Life beyond Earth
Ovcharenko, Vladyslav ; Jehlička, Jan (advisor) ; Culka, Adam (referee)
The relevance of the topic of the bachelor's thesis "Current exobiology missions to Mars" is associated with the awareness of the similarity of some conditions and processes on Earth and Mars. Compared to other planets of the Solar system, Mars is somehow relatively close to our planet in major characteristics: the inclination of the equatorial plane, relief, the length of the day, some atmospheric processes, temperature conditions, etc. Having studied the processes taking place there now, we can better deal with the past and predict the future evolution not only of Mars, but also of Earth. The aim of this work is to overview the current exobiological missions of NASA and ESA to Mars and the assessment of the importance of the information received for earth sciences and search of life beyond the Earth. The subject of Exobiology consists in studies of potential origin, evolution, spread of life on other planets of the universe. Exobiology includes search for habitable environments both in the Solar system and beyond, detecting biomarkers, search of evidence of prebiotic chemistry, and research on potential possibilities of life in terms of adapting to extreme conditions in space. Based on the foregoing, we can state that the exploration of Mars opens up grandiose prospects for science and technology...
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Application of Raman spectroscopy for detection of sulfates of self-ignited coal heaps
Košek, Filip ; Jehlička, Jan (advisor) ; Němec, Ivan (referee) ; Vandenabeele, Peter (referee)
This Ph.D. thesis was focused on the application of Raman spectroscopy as the main analytical method for the characterization of neo-formed minerals, notably sulfates, from burning coal waste dumps. This environment associated with subsurface fires gives rise to a variety of uncommon and rare minerals. The specific features of these minerals (metastability, hygroscopy, mixed aggregates) causes that the mineralogical investigation is a challenging task using traditional laboratory-based techniques. Advantages such as the non-destructive nature, the sensitivity to the changes in the hydration degree of sulfates, little or none pretreatment, and the option of measurements directly in the field were the main reasons for applying this spectroscopy method. The scarce availability of spectroscopic data of most gas-vent minerals can be considered as the disadvantage. Therefore, artificial prepared samples of six anhydrous sulfates, which are rarely found in nature, were analyzed by Raman laboratory spectroscopy and a miniature a Raman spectrometer, and specific Raman features as well the differences with hydrated counterparts are shown. Laboratory investigation of two natural hydrated aluminum sulfates, alunogen and khademite, were carried out using Raman spectroscopy and other methods in order to obtain...
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Carotenoids of snow algae as biomarkers for exobiology: Raman spectroscopic perspective
Němečková, Kateřina ; Jehlička, Jan (advisor) ; Němec, Ivan (referee)
The major aim of this thesis is critical evaluation of Raman spectroscopy in the detection of carotenoids of extremophiles, namely snow algae. Extremophilic microorganisms play an important role in exobiology since they set hypothetical boundaries for the presence of life on Earth. Raman spectroscopy will be a part of two mission to Mars. Here, a laboratory Raman microspectrometer was used for the analysis of 11 samples of snow algae from different locations over the years 2002-2017. The acquired spectra were compared with HPLC/UV-VIS analysis. The results showed that the ability of Raman spectroscopy to discriminate between structurally slightly differing carotenoid pigments or several carotenoids in an admixture is limited. Contrary, HPLC/UV-VIS permitted to detect various structurally similar carotenoids (and chlorophylls). However, HPLC/UV-VIS worked with overall pigment extracts during which some structural information can be lost. Raman microspectrometer allowed analysis of cells in different life-cycle stages and thus several various spectra could be studied. Raman microspectrometer was therefore more suitable for carotenoid detection in mixtures of various life-stages than HPLC/UV-VIS. Key words carotenoids, snow algae, exobiology, habitability, biomarker, Raman spectroscopy, HPLC/UV-VIS
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Application of Raman spectroscopy for the identification of organic inclusions in minerals for the field of exobiology
Osterrothová, Kateřina ; Jehlička, Jan (advisor) ; Němec, Ivan (referee) ; Vandenabeele, Peter (referee)
The multidisciplinary field of astrobiology has grown rapidly in recent years. The major goals of research in the field have been the search for habitable environments both within and outside our solar system, the search for evidence of prebiotic chemistry and life on Mars and other bodies in our solar system, laboratory and field research into the origins and early evolution of life on Earth, and studies of the potential for life to adapt to challenges on Earth and in space. NASA and ESA are heavily focused on a number of upcoming exploratory missions (e.g., the Mars Science Laboratory, with its planned launch in the fall 2011; ExoMars 2018; and the follow-up Mars Sample Return missions beyond 2020). A Raman spectrometer is now being miniaturized for the ExoMars Rover Instrument Suite. This Raman instrument is expected to be used to identify organic compounds and mineral products that could be related to signatures of life, as well as provide a general mineralogical overview, especially those minerals produced by water- related processes. This thesis describes the results of laboratory investigation into the feasibility of Raman spectroscopy to detect different types of biomarkers (pigments, carboxylic acids, and aminoacids) first mixed in the mineral matrices and...
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