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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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Estimation of structural state of carbonaceous matter of metasedimentary rocks using Raman spectroscopy
Kdýr, Šimon ; Jehlička, Jan (advisor) ; Machovič, Vladimír (referee)
Metamorphic processes can transform the organic matter in sedimentary rocks into structurally organized carbonaceous matter, in ideal conditions to graphite. In the centre of West Alpine arch, the metasedimentary rocks are rich in dispersed carbonaceous matter and were used in this thesis to specify the thermal range of metamorphism based on the structural state. Previous studies have used mainly the Raman spectrometers to determine the structural state of carbonaceous matter. Unfortunately this method doesn't allow in-situ analyses which, in addition to Earth studies, can be essential for studying other planetary bodies and moons of our solar system. As only the smallest and lightest instruments are required for analyses during potential planetary missions to Mars, it is important to verify that the small instruments are able to detect even the small concentrations of carbonaceous matter. Currently available miniature and portable Raman spectrometers have started to become more precise but are still not as precise as laboratory Raman microspectrometers. This thesis is divided into two parts. First part aims to duplicate the results from previous studies by Raman microspectrometers in the West Alpine arch. Furthermore, the excitation laser wave length dependence of spectral signs in carbonaceous...
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Identification of precious stones using portable Raman spectrometers: advantages and limits during in situ applications
Minaříková, Laura ; Jehlička, Jan (advisor) ; Machovič, Vladimír (referee)
This thesis investigates the potential and limits of portable Raman spectrometers for their application in situ in the environment of museum collections. The data sets were obtained at the two locations. The first measurement took place in the Jewish Museum in Prague. Here we have studied stones from a silver Torah shield from the first half of the nineteen century. This shield is decorated with a set of precious and semi-precious stones and glass imitations. The shield originates from Poland and has been studied using two portable Raman spectrometers (785 nm and 532 and excitations). The second measurement took place in the premises of the Prague Loreto where we had available, at that time still unshown, objects of art for the forthcoming new exhibition. It was about jewelry like earrings, rings, bracelets and brooches, also about ordinary objects of daily use like mirrors, bowls and perfume bottles, or about the objects with religious themes, mostly crowns for the Virgin Mary and baby jesus. The obtained Raman bands correspond well with the reference values of the minerals, the deviation ranged in the order of +/- 3 cm-1 , which in general permits unambiguous identification of phases. Portable handheld Raman spectrometers working with a laser wavelength of 785 nm and 532 nm were able to quickly...
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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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Use of Raman spectrometry in the environmental areas
Šotkovský, Jakub ; Jehlička, Jan (advisor) ; Machovič, Vladimír (referee)
This work deals with the use of Raman spectroscopy in environmental analysis focused on aerosols and slags from pyrometallurgical processes. This is a practical analysis of the publications in which the authors deal with chemical conditions and the structure of these waste products resulting from metallurgical processes in the context of their risks and the impact on the environment. Raman spectroscopy is a suitable method for identification of substances for the qualitative and quantitative structural analysis. This method can detect even very small particles and speciation or oxidation states. The advantage of this method is its nondestructivity. Also there is no chemical changes and no thermal damage of the sample while using this method. Another indisputable advantages of the mobile Raman spectrometer is the speed at which the system can detect the desired properties of materials in-situ and even in extreme conditions.
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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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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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