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Characterization of a new deposition system for coating the fibers
Zvonek, Milan ; Salyk, Ota (referee) ; Čech, Vladimír (advisor)
Cieľom bakalárskej práce je charakterizácia depozičného systému na výrobu tenkých vrstiev. Teoretická časť je zameraná na literárnu rešerš o plazme, plazmovej polymerácií, tenkých vrstvách a ich analýzu pomocou infračervenej spektroskopie a spektroskopickej elipsometrie. Experimentálna časť popisuje použité materiály a aparaturu použitú na prípravu tenkých vrstiev pomocou plazmovej polymerácie. Posledná časť popisuje výsledky merania depozícií tenkých vrstiev a ich vyhodnotenie vzhľadom na depozičné podmienky.
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Utilization of vibrational spectroscopy in study on interactions between humic substances and organic ions.
Stehlíková, Kristína ; Enev, Vojtěch (referee) ; Sedláček, Petr (advisor)
The main objective of this bachelor thesis was to validate the potential of the utilization of vibrational spectroscopy in the study on interactions between humic substances and organic ions. Unmodified (HA) and methylated humic acids (mHA) were chosen as model humic substances and organic ions were represented by methylene blue, rhodamine 6G and Septonex. Firstly, a suitable infrared spectroscopy technique was chosen. The results of optimization measurements showed that spectra with the best resolution can be obtained using the DRIFTS technique. The next part of the thesis discusses the effect of methylation in the structure of humic acids. Significant differences were recorded in mHA compared to the unmodified humic acids. Finally, the spectra of humic acid – organic ion complexes were compared to the spectra of prepared blank samples. It was noted that the spectra of complexes are not only a simple sum of the pure individual substances’ spectra, but also shifts and changes in the intensity of different absorption bands were recorded there. It suggests that non-covalent interactions played an important role in the complexes. Infrared spectroscopy was proved to be a useful method for investigating these interactions.
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Evaluation of the quality of collagen samples in solid phase using circular dichroism
Ďubašák, Matej ; Žídek, Jan (referee) ; Vojtová, Lucy (advisor)
Diplomová práca sa zaoberá novou kvalitatívnou analýzou kolagénových vrstiev pomocou cirkulárneho dichroizmu v pevnej fáze. Teoretická časť opisuje kolagén a jeho sekundárnu štruktúru, spektroskopické metódy cirkulárneho dichroizmu (CD) a zoslabenej úplnej reflektancie (ATR). Experimentálna časť sa zaoberá prípravou homogénnych a transparentných kolagénových filmov a optimalizáciou objemu, koncentrácie a sušenia. Následne sa zmerala a vyhodnotila kalibračná krivka s rôznymi pomermi kolagénu a želatíny. Získaná rovnica lineárnej regresie sa použila na stanovenie obsahu kolagénu v modifikovaných vzorkách. Výsledky hodnotených modifikovaných vzoriek boli porovnané s meraniami ATR spektroskopie. Merania ATR ukázali vyšší obsah kolagénu ako CD merania. Vzorky s najnižším a najvyšším obsahom kolagénu sú pre obe metódy rovnaké. Dokazuje to, že môžme porovnávať vzorky s rôznym obsahom kolagénu navzájom, ale nemôžeme určiť presný obsah kolagénu pripojením týchto dvoch metód. Optimalizovaná metóda CD sa môže použiť na prípravu a meranie presného obsahu kolagénu vo vzorkách, najmä v rámci výroby kolagénu, aby sa dosiahla konštantná kvalita kolagénu v každom kroku výroby.
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Metallic nanostructures with three-dimensional topography for plasmonics
Rovenská, Katarína ; Kvapil, Michal (referee) ; Ligmajer, Filip (advisor)
Due to high concentration of free electrons, metallic nanostructures can support plasmonic resonances. The spectral shape of plasmonic resonances may be tuned by many factors and because of it, the field of their application, given by their capability of focusing light under the diffraction limit, broadens. This thesis deals with fabrication of gold nanostructures by electron beam litography on top of a silicon substrate. The topography of the substrate is subsequentially modified by wet anistropic etching. A part of this thesis also briefly reviews methods for fabrication of nanostructures with planar or three-dimensional topography. Using the infrared spectroscopy, this thesis further analyzes the effect of size, shape, spacing of the nanostructures, and also the substrate topography on the optical response of the fabricated nanostructures. The outcomes of this thesis verify previously described tendencies of spectral relations between optical properties and named parameters in the mid-infrared region.
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Involvement of vibrational spectroscopy in the study on interactions of natural organic matter with model environmental pollutants.
Stehlíková, Kristína ; Enev, Vojtěch (referee) ; Sedláček, Petr (advisor)
The main objective of this diploma thesis was to verify the potential of using advanced infrared spectra processing techniques – specifically the principal component analysis (PCA) – in order to monitor the interaction of natural organic matter with organic pollutants. Natural organic matter was represented by standard IHSS Leonardite humic acid, while the aromatic dyes methylene blue and Rhodamine 6G and the aliphatic substance Septonex were chosen as representatives of organic ions. Their interactions were monitored using Fourier-transform infrared spectroscopy, the use of which for this purpose was verified in my bachelor's thesis. Principal component analysis was finally applied to the obtained infrared spectra of the formed complexes and prepared blank samples, which helped to reveal spectral changes at first glance unrecognizable in the spectra themselves. It was found out that the most likely mechanism of humic acid interaction with aromatic pollutants is a - interaction, while the electrostatic nature of the interaction is assumed for the binding of aliphatic substances.
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Utilization of vibrational spectroscopy in study on interactions between humic substances and organic ions.
Stehlíková, Kristína ; Enev, Vojtěch (referee) ; Sedláček, Petr (advisor)
The main objective of this bachelor thesis was to validate the potential of the utilization of vibrational spectroscopy in the study on interactions between humic substances and organic ions. Unmodified (HA) and methylated humic acids (mHA) were chosen as model humic substances and organic ions were represented by methylene blue, rhodamine 6G and Septonex. Firstly, a suitable infrared spectroscopy technique was chosen. The results of optimization measurements showed that spectra with the best resolution can be obtained using the DRIFTS technique. The next part of the thesis discusses the effect of methylation in the structure of humic acids. Significant differences were recorded in mHA compared to the unmodified humic acids. Finally, the spectra of humic acid – organic ion complexes were compared to the spectra of prepared blank samples. It was noted that the spectra of complexes are not only a simple sum of the pure individual substances’ spectra, but also shifts and changes in the intensity of different absorption bands were recorded there. It suggests that non-covalent interactions played an important role in the complexes. Infrared spectroscopy was proved to be a useful method for investigating these interactions.
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Evaluation of the quality of collagen samples in solid phase using circular dichroism
Ďubašák, Matej ; Žídek, Jan (referee) ; Vojtová, Lucy (advisor)
Diplomová práca sa zaoberá novou kvalitatívnou analýzou kolagénových vrstiev pomocou cirkulárneho dichroizmu v pevnej fáze. Teoretická časť opisuje kolagén a jeho sekundárnu štruktúru, spektroskopické metódy cirkulárneho dichroizmu (CD) a zoslabenej úplnej reflektancie (ATR). Experimentálna časť sa zaoberá prípravou homogénnych a transparentných kolagénových filmov a optimalizáciou objemu, koncentrácie a sušenia. Následne sa zmerala a vyhodnotila kalibračná krivka s rôznymi pomermi kolagénu a želatíny. Získaná rovnica lineárnej regresie sa použila na stanovenie obsahu kolagénu v modifikovaných vzorkách. Výsledky hodnotených modifikovaných vzoriek boli porovnané s meraniami ATR spektroskopie. Merania ATR ukázali vyšší obsah kolagénu ako CD merania. Vzorky s najnižším a najvyšším obsahom kolagénu sú pre obe metódy rovnaké. Dokazuje to, že môžme porovnávať vzorky s rôznym obsahom kolagénu navzájom, ale nemôžeme určiť presný obsah kolagénu pripojením týchto dvoch metód. Optimalizovaná metóda CD sa môže použiť na prípravu a meranie presného obsahu kolagénu vo vzorkách, najmä v rámci výroby kolagénu, aby sa dosiahla konštantná kvalita kolagénu v každom kroku výroby.
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Derivatization of the micro-samples of natural polymers with similar composition for FTIR analysis
Dudičová, Dorota ; Červený, Václav (advisor) ; Dian, Juraj (referee)
in English This master thesis is focused on verifying the possibility of optimizing FTIR spectrometric analysis of terpenic resins using derivatized (fluorinated) samples using XtalFluor-E in combination with triethylamine trihydrofluoride as an agent. Terpenic resins have very similar FTIR spectra, so for their better differentiation, they need to be derivatized to minimize the influence of overlapping spectral bands in FTIR spectra. This work aimed to create a methodology for derivatization of samples of natural polymers for the National Technical Museum in Prague, where the work was performed. Samples of terpenic resins were measured non-fluorinated by the ATR crystal method and by transmission, after fluorination, only the ATR crystal method was used. Different fluorination conditions, different times (2, 4, 6, 24 and 96 hours), the effect of sample rinsing (diethyl ether, ethylene tetrachloride) and the effect of matrix on the sample (KBr pellet) were tested. Fluorination has shown to be effective. Four hours of fluorination and the need to rinse the sample with diethyl ether were chosen as the optimal fluorination conditions. After testing the resins themselves, fluorinated samples of violin varnishes and samples of historical varnishes from harp and piano were analyzed. Their spectra before...
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Low temperature plasma diagnostics by Cavity Ring-Down Spectroscopy
Kassayová, Miroslava ; Dohnal, Petr (advisor) ; Morávek, Matěj Jan (referee)
Low temperature plasma occurs in interstellar gas clouds, solar system, ionosp- here of the Earth and is used in plasmatic technologies. The study of the reactions of simple atomic or molecular ions with molecules and electrons in low temperature plasma allows better understanding of chemical processes in interstellar gas clouds and atmospheres of gas giants and gives feedback for quantum mechanical calcula- tions. It also allows to connect new facts gained via astronomical observations. The parameters of plasma (kinetic and rotational temperature of ions, their concentra- tions, etc.) may vary and many diagnostic technics are used to determine them. The aim of this bachelor thesis is to find suitable infrared transitions of N2H+ and utilize them for spectroscopical study of the electron - ion recombination of N2H+ ions with electrons. 1
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Metallic nanostructures with three-dimensional topography for plasmonics
Rovenská, Katarína ; Kvapil, Michal (referee) ; Ligmajer, Filip (advisor)
Due to high concentration of free electrons, metallic nanostructures can support plasmonic resonances. The spectral shape of plasmonic resonances may be tuned by many factors and because of it, the field of their application, given by their capability of focusing light under the diffraction limit, broadens. This thesis deals with fabrication of gold nanostructures by electron beam litography on top of a silicon substrate. The topography of the substrate is subsequentially modified by wet anistropic etching. A part of this thesis also briefly reviews methods for fabrication of nanostructures with planar or three-dimensional topography. Using the infrared spectroscopy, this thesis further analyzes the effect of size, shape, spacing of the nanostructures, and also the substrate topography on the optical response of the fabricated nanostructures. The outcomes of this thesis verify previously described tendencies of spectral relations between optical properties and named parameters in the mid-infrared region.
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