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Estimation of Raman spectrometric instruments (785 nm excitation) for detection of dark minerals
Šimon, Jan ; Jehlička, Jan (advisor) ; Machovič, Vladimír (referee)
Summary: Raman spectroscopy is a widely used method in geoscience fields. Using a portable Raman spectrometer is possible to identify different materials, Raman spectrometer will participate in the survey the Martian surface. Its use is widely applied in mineralogy. There was measured a set of dark, green and some bright minerals of different mineralogical system groups that have been assessed the applicability of the chosen detector excitation at 785 nm mainly off-road equipment. The obtained spectra were measured off-road equipment ahura at excitation 785 nm and laboratory equipment InVia Renishaw and there were used lasers at excitaion of 785 nm and 514 nm. It was set of these minerals: Prehnite, Sulphur, Tyrkenit (howlit), Pyroxene (diopside), Libethenite, Toutmaline (verdelite), Dioptas, Klinoklas, Langit, Jadeit, Pseudomalachit (ehlit), Actinolite, Epidote, Augite. Results are composed of field measurement device Ahura, with excitation 785 nm and laboratory apparatus Invite Renishaw excitations with 785 nm and 514 nm. Measured values are arranged in tables, where the measurements are compared with each other, including literature and reference graphically demonstrated in the form of spectra. Subsequently evaluated their measurability. Keywords: Raman spektroscopy, portable Raman spectrometer,...
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Methods for distinguishing fossil and recent organic matter in post mining soils
Vindušková, Olga ; Frouz, Jan (advisor) ; Jehlička, Jan (referee)
Soil organic matter (SOM) has many important effects on soil and ecosystem quality. Soils developing on post-mining sites are characteristic of low recent SOM, but can contain reasonable amounts of fossil SOM originating from coal, kerogen or other fossil component of the overburden. With time, as vegetation develops, SOM accumulates and improves overall quality of post-mining soils. To assess soil quality development and quantify sequestered carbon, a reliable method for distinguishing recent and fossil SOM is needed. The relative amounts of recent and fossil carbon can be successfully quantified by the radiocarbon method, but due to it's high cost, it's common application is unlikely. The aim of this study was to (1) quantify the amount and variability of fossil SOM in post-mining soils near Sokolov, (2) compare different other SOM quantification methods to this reference, (3) test the potential of near infrared spectroscopy for recent and fossil carbon quantification. Fossil carbon accounts for 13 to 99 % of total organic carbon in studied soils, which is equivalent to 2 - 6% carbon content. Subtracting the carbon content of a deeper horizon (50 cm) from the content of A horizon provides a good estimate of recent carbon. This can be applied to carbon contents from dry combustion, wet dichromate...
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Detection of nitrogen containing biomarkers using portable Raman spectrometers - use in exobiology
Schneedörfler, Rudolf ; Jehlička, Jan (advisor) ; Machovič, Vladimír (referee)
This thesis was focused on testing of portable Raman spectrometer for detection of components in model mixtures of five different biomolecules in a gypsum matrix. The main goal was to test the ability of the instrument to detect amino acids glycine, L-proline, L-alanine and nucleobase thymine in samples containing UV protective pigment -carotene. Other measurements were taken using the laboratory inVia Reflex instrument to comapare the results gained from the portable Raman spectrometer. Both instruments were equipped with the excitation laser working at 785 nm wavelength. It was found out that it is possible to detect amino acid in mixtures containing -carotene at the lowest concentration of amino acid 100 g/kg and the maximum concentration of -carotene 1 g/kg. Thymine could be identified at the concentration of 100 g/kg in mixtures with higher concentration of -carotene (10 g/kg). In mixtures of -carotene at the concentration of 1 g/kg and only one of the studied nitrogen containg compounds (at the concentration of 100 g/kg) in the gypsum matrix, it was possible to detect all present components. In mixtures containing two nitrogen compounds with -carotene at the concentration of 1 g/kg in the gypsum matrix, both nitrogenous compounds could be detected. When measuring the samples of the three nitrogen...
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Estimation of Raman spectrometric instruments (785 nm excitation) for detection of dark minerals
Šimon, Jan ; Jehlička, Jan (advisor) ; Machovič, Vladimír (referee)
Summary: Raman spectroscopy is a widely used method in geoscience fields. Using a portable Raman spectrometer is possible to identify different materials, Raman spectrometer will participate in the survey the Martian surface. Its use is widely applied in mineralogy. There was measured a set of dark, green and some bright minerals of different mineralogical system groups that have been assessed the applicability of the chosen detector excitation at 785 nm mainly off-road equipment. The obtained spectra were measured off-road equipment ahura and delta nu at excitation 785 nm and laboratory equipment InVia Renishaw and there were used lasers at excitaion of 785 nm and 514 nm. It was set of these minerals: Prehnite, Sulphur, Tyrkenit (howlit), Pyroxene (diopside), Libethenite, Toutmaline (verdelite), Dioptas, Klinoklas, Langit, Jadeit, Pseudomalachit (ehlit), Actinolite, Epidote, Augite. Some minerals were measured off-road equipment acquired spectrum, witch corresponded with laboratory measurements, the spectra of other optical properties due to their ambiguous. Keywords: Raman spektroscopy, portable Raman spectrometer, mineralogy, dark and green minerals
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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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Use of miniaturized Raman spectrometers under field conditions (sulphates)
Košek, Filip ; Jehlička, Jan (advisor) ; Osterrothová, Kateřina (referee)
Sulphates represent apparently an important component of Martian rocks and regolith. Their detection and identification is an integral part of the planned exploration missions, as they provide valuable information about the geological history of the planet. Also they could play a crucial exobiological role related with the possibility of existence of extinct or extant Martian life. This thesis provides a comprehensive overview of the occurrence and the geological situation of sulphates on the surface of Mars. The basic genetic factors responsible for formation of sulphates are introduced in terrestrial and Martian conditions. Furthermore, their significance is explained as indicators of geological factors and their connection with a possible Martian life. The second part presents method of Raman spectroscopy and its application in exobiology. The advantages and limitations of laboratory and portable instruments for analyzes exobiological samples are described. Identification capabilities of this method for determination of sulphates are shown, as well as its use on real locations considered as exobiological analogues. At the end, the current concept of Raman spectrometer for ExoMars rover is introduced. Keywords: Miniaturized Raman spectrometers, field conditions, sulphates
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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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Inclusions in fossil resins
Hähnel, Lydia ; Jehlička, Jan (advisor) ; Vítek, Petr (referee)
My Bachelor thesis, having a background research character, is focused onto amber and its inclusions. In the first part of my thesis, I give some general information on amber: its characteristics and formation, factors for the preservation of inclusions in amber, and distribution of amber. The second part gives a short describtion of methods for amber research. The main focus is on scanning electron microscopy and Raman spectroscopy. I depict some points of the research of geographical and botanical origin of the samples too. As for the last part, I try to get from the rather theoretical explanations to practical points of amber research: what information can amber and its inclusions offer to us? I summarize a few results of amber research which are devided into three groups: information about the climate in which the sample was formed, information on the evolution of life, and information on coexistence of species.
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Application of Raman spectroscopy for study of nitrogen containing compounds for astrobiological purposes
Culka, Adam ; Jehlička, Jan (advisor) ; Vlčková, Blanka (referee) ; Frank, Otakar (referee)
IV ABSTRACT This PhD thesis was focused on the evaluation of the application of Raman spectroscopy as an analytical method used specifically for research on selected nitrogen containing compounds in experiments, that are important in the astrobiological context. The results of experiments provided insight into the advantages as well as the limitations of the method in several applications that are expected to be encountered in the future planetary exploration missions with astrobiological context use, and where the Raman spectroscopy is proposed as an advantageous method. The Raman spectroscopy was tested in various experimental tasks. Several nitrogen containing minerals were analysed, where the features such as the indestructive analysis, small laser spot size, and selection of the excitation source enabled to acquire spectra of minerals even with miniature sample sizes, also the band assignment was published for the first time for some of the studied minerals. Artificially prepared samples of biomarkers mixed in mineral matrices were analysed to test the ability of the method to analyse complex mixtures: three biomarkers and two evaporitic minerals were analysed with a portable instrument, and all compounds were unambiguously detected. When the samples contained more of the similar compounds with many...
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Identification of microbial pigments in evaporites using Raman spectroscopy: implications for astrobiology
Vítek, Petr ; Jehlička, Jan (advisor) ; Marshall, Craig P. (referee) ; Vandenabeele, Peter (referee)
Raman spectroscopy is a powerful tool for identification both inorganic and organic compounds including microbial biomolecules. Together with the fact, that it is considered to be the important nondestructive instrument for use on Mars within future robotic missions, it is necessary to assess its capabilities in scenarios relevant for both Martian and terrestrial conditions. In this work, the potential of Raman spectrometry was tested - including both bench-top laboratory systems as well as portable counterparts - to detect traces of life within evaporitic matrices through biomolecular identification. Due to their chemical and physical nature resulting in optical properties, pigments are important organic compounds in Raman spectroscopic analysis using visible excitation. Hence in this work we have focused on the Raman spectroscopic identification of pigments as biomarkers with relevance for investigation of life in both extreme terrestrial and potentially extraterrestrial environments. Results of methodical work are presented in Appendices I to III, dealing particularly with β-carotene as a model carotenoid pigment. The concentration limits of this biomarker in three different evaporitic matrices (halite, gypsum and epsomite) have been determined for artificially prepared powdered mixtures alone...
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