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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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Oxalates in rocks and plants
Novotná, Julie ; Hruška, Jakub (referee) ; Jehlička, Jan (advisor)
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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Koncepce a metodologie komplexního studia dlouhodobých trendů vývoje krajiny v užším a širším zázemí JE Temelín: Stanovení potenciálních změn kvalitativních a kvantitativních parametrů půd s ohledem na způsob a intenzitu jejich využívání a zranitelnosti vůči antropogenní zátěži na základě historických podkladů a aktuálních výsledků sledování
Česká zemědělská univerzita v Praze, Fakulta agrobiologie, potravinových a přírodních zdrojů, Katedra pedologie a geologie, Praha ; Jehlička, Jan ; Němeček, Karel ; Němeček, Jan ; Kozák, Josef
Podrobný popis geomorfologických a geologických poměrů sledované lokality. Byla navržena umístění kopaných půdních sond tak, aby zahrnula nejdůležitější půdní jednotky oblasti a současně napomohla upřesnění půdních map, zejména u přechodu zemědělská půda - půda lesní. Výsledky sledování - geomorfologické poměry, geologické poměry, výsledky fyzikálních a chemických analýz. Byla vytvořena pracovní verze nové digitální mapy půd zájmového území.
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