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Possibilities of Raman spectrometry application by Fire Brigade Units
Mičánková, Helena ; Osvald, Josef (referee) ; Čáslavský, Josef (advisor)
Thesis is focused on the application of Raman’s spectometer Ahura First Defender in cooperation with Fire Department. Theoretical part describes principles and development of Raman spectrometry and possibilities of its application. Practical part focus on identification of unknow substances in case studies and interpretation of the results. Final part of thesis evaluates contribution of Raman spectrometry for fast indentification of unknow compounds for Fire Rescue Brigade in the Czech Republic.
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Detecting biomarkers of extremophiles in Martian analogues
Němečková, Kateřina ; Jehlička, Jan (advisor) ; Hauer, Tomáš (referee) ; Vandenabeele, Peter (referee)
The main focus of this thesis is on the examination of endolithic microorganisms within gypsum from Sicily. This region is of particular interest because gypsum outcrops are common and accessible there, but the environment is not considered to be extreme in terms of solar radiation or other factors. The research aims to detect endolithic biomarkers and analyse their distribution in their natural environment, to identify endoliths with a focus on phototrophs, and to assign the detected biomarkers to their producers. One of the key tools used in this study was a portable Raman spectrometer with a 532 nm laser, used for the detection of carotenoids under field conditions. Further, the Raman fingerprints of scytonemin and gloeocapsin can be used for the taxonomic identification of some cyanobacteria. With the use of a combination of different excitation wavelengths (445nm, 532 nm, 780 nm), it was possible to detect good quality spectra of various pigments in situ, conditions also in isolated cells and colonies. The results of the molecular analysis also suggest that gypsum habitats in non-extreme regions have a similar microbial composition as those found in extreme regions; i.e., Cyanobacteria being the most abundant group of these microorganisms. This has previously been described as the "hypothesis...
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Raman spectormetry in Art
Minaříková, Laura ; Jehlička, Jan (advisor) ; Osterrothová, Kateřina (referee)
This thesis deals with the use of Raman spectroscopy in the arts, specifically in the identification of precious stones and semi-precious stones in various art works. This work describes the basics of this method, options and practical use based on selected scientific publications. The existing results of research in recent years shows that this spectroscopic analytical method on the rise. It is thanks to the many advantages that this method offers skilled in the art. The main advantages of Raman spectroscopy include speed and affordability analysis, minimal or no sample preparation, and most importantly - non-destructive to sample and explore the possibility of sample on the spot, without having to often very difficult transport to the laboratory. Key words Raman spectrometry, art, characterization of artifacts
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Use of portable Raman spectrometers for detection of sulfates: potential application in exobiology
Košek, Filip ; Jehlička, Jan (advisor) ; Němec, Ivan (referee)
The detection of mineral phases under in situ conditions has become a primary but sometimes also challenging task in many fields of geoscience. Raman spectroscopy has been used as a powerful tool for the identification of various minerals and organic compounds. The advantages and the relative simplicity made this method a promising choice in the future planetary exploration missions to Mars. The deposits of aqueous minerals including sulfates have been found on the Martian surface. With the development of miniaturized handheld spectrometers there is a need for evaluation of Raman spectroscopy as a method of identification of sulfate phases in their natural conditions. In the first part of this work a handheld spectrometer equipped with 532 nm excitation laser was tested under laboratory conditions during which the ability to distinguish mineral samples representing sulfates of different chemical composition and different degree of hydration was investigated. In the second part, two handheld Raman spectrometers equipped with 532 and 785 nm excitation lasers were used for the characterization of sulfate phases on sites of their natural occurrence located in the Czech Republic. The quality of the Raman spectra acquired under outdoor conditions by both spectrometers was rather average but sufficient to...
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Anthracological analysis of chernozems in Czechia
Danková, Lenka ; Šefrna, Luděk (advisor) ; Zádorová, Tereza (referee)
This thesis deals with a pedogenesis of chernozems in Czechia (Central Europe). It solves a problem with open landscapes in Central Europe, further a role of man and fires in formation of this soils and relation between colour of chernozems and the content of black carbon. In my thesis is represented pedoanthracology as a method, which can be useful for future study of open landscapes in Central Europe and for an influence of man. In this thesis, there were also analysed two chernozemic soils with Raman spektrometry. It was found out, that chernozems was probably formed under forest-steppe vegetation with residue of post glacial steppe. Anthropogenic activity and fires could be new factors of pedogenesis of Central European chernozems. It was showed a strong relation between colour and content of BC. Raman spectrometry found a presence of BC in our analysed soils.
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Extremophiles and their environments - possibilities of using Raman spectroscopy for key biomarkers detection
Kovács, Michal ; Jehlička, Jan (advisor) ; Osterrothová, Kateřina (referee)
The Earth has a huge variety of living environments. Most of them, in terms of human, are affected by factors with extreme values. Species diversity, especially in the world of microorganisms, have created adaptations that help manage these conditions. Organisms, which live in these conditions, are called extremophiles. Each of them leaves a trace of their existence, whether present or past. These traces are called biomarkers and if we use appropriate method, we are able to identify them. This bachelor thesis brings a brief overview of the basic extremophiles and the environment in which they live. Furthermore, briefly describes the use of Raman spectroscopy to identify significant biomarkers, such as for the needs of exobiology.
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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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Raman spectrometry of pigments of cyanobacteria, algae and lichens in the astrobiology context
Kovács, Michal ; Jehlička, Jan (advisor) ; Osterrothová, Kateřina (referee)
This work deals with the possibility of Raman spectroscopical identification of selected biomarkers of extremophile species. It focuses mainly on selected cyanobacteria, algae and lichens with an emphasis on the ability to detect carotenoids. These pigments exhibit three characteristic bands of Raman spectra which represent stretching vibrations C=C; C-C and bending vibration C-CH3 in molecules of carotenoids. Raman spectra were measured not only by laboratory microspectrometers (λ - 514 nm and 532 nm), but also by portable and handheld spectrometers (λ - 532 nm, 785 nm and 700 - 1100 nm). In the case of cyanobacteria, the spectroscopical analysis was performed also on the fractions obtained by high performance liquid chromatography (HPLC). This work critically evaluates the possibilities of Raman spectroscopy to identify the carotenoids of cyanobacteria, algae and lichens. Besides the signal of carotenoids, interpretation of other bands in the Raman spectra corresponding to the presence of other biomarkers is given here for selected samples. The obtained Raman spectra of carotenoids should be interpreted with great caution, because of the ifluence of several factors, which potentially cause unsystematic shifts in the positions of Raman bands (carotenoids bond in biological tissue, interactions with...
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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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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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