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Studies of Lanthanide Complexes by a Combination of Spectroscopic Methods
Krupová, Monika ; Bouř, Petr (advisor) ; Kapitán, Josef (referee)
Studies of Lanthanide Complexes by a Combination of Spectroscopic Methods Monika Krupová (Department of Physical and Macromoecular Chemistry, Faculty of Science, Charles University in Prague) Since conventional structural analysis offers rather limited means for the chirality detection, a series of lanthanide tris-(β-diketonates) are investigated as effective receptors for a better chirality sensing in biomolecular substrates. These lanthanide complexes containing β-diketonate ligands are electrically neutral; they can further coordinate with various small organic molecules such as chiral alcohols, amino alcohols or amino acids in organic solvents and produce a strong chiral signal. Previously, a resonance in Raman scattering was observed in the studied systems due to the correspondence of europium electronic transition energy to the laser excitation wavelength, about a 100-fold signal enhancement if compared to non-resonant vibrational ROA was observed. This enabled shorter detection times as well as lower sample concentrations. In the current work, interaction of the Eu(FOD) complex with (R)- and (S)- enantiomer of 1-phenylethanol in n-hexane was studied using IR spectroscopy, Raman spectroscopy and Raman optical activity (ROA), UV-Vis spectroscopy and ultraviolet circular dichroism (UVCD). Only...
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Comparison of effectiveness of teaching using computers vs. 3D models
Andělová, Denisa ; Janštová, Vanda (advisor) ; Jáč, Martin (referee)
Currently, pupils' interest in science continues to decline, although this area of education is very important in every day life (medicine, environment, etc.) and there is high demand for science professions on the labor market. Molecular biology curriculum concerning DNA and the transfer of genetic information is abstract and difficult topic for pupils to imagine, and for teachers to explain. There are many ways to teach this topic. Very popular are iquiry and laboratory practise. But not all schools have their own laboratories, and can teach molecular practical effectivelly. Inquiry based teaching is time consuming to prepare, and not every topic is appropriate to be taught this way. Another possibilities how to visualize "invisible" molecules and processes are computer software and animations or 3D physical model. In my thesis, I examined the effect of using computers and animations to teach abou DNA compared to using a 3D physical model on students' knowledge. I laso tested the possible influence of gender and pupils' preferences on their achieved score on knowledge tests. The research was performed in five classes at three high schools in Prague. Students in year 12 were on different types of high school and some of them took special biology class, their age was between 15 and 18 years. The...
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Crystal and molecular structure study of garnets from selected localities of the České středohoří Mts.
Píšová, Barbora ; Skála, Roman (advisor) ; Laufek, František (referee)
Major and minor element contents of garnets from mantle peridotites and eclogites brought to the surface by volcanic rocks of the České středohoří Mts. were determined by an electron probe microanalyzer. Garnets are homogenous and their chemical composition corresponds to solid solution containing 65-71 % pyrope, other end members significantly present are almandine, uvarovite and grosulare. This method also help to discover polyphase inclusions chemically corresponding to amphiboles (pargasite, cummingtonite, magnesio-hornblende and katophorite). Next to amphiboles following minerals were found in inclusions: omphacite, carbonates, phlogopite, clinochlore, olivine, apatite, spinel group minerals, and sulfidic phases potentially close to pentlandite. Samples were also analyzed by powder X-ray diffraction. Qualitative phase analysis confirmed pyrope homogeneity. The refinement of crystal structure parameters was performed by the Rietveld method. Raman microspectroscopy showed shifts of individual bands in the Raman spectra compared to those of pure pyrope. Position of bands in spectra differs due to the substitution of Ca for Mg at the dodecahedral sites of the structure. Mutual positive correlations among elements Cr, Ca, Mg, Al, Si, Mn, Ti and Na were observed. Correlations were found also between...
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Calculations of photoelectron spectra of small water clusters using the independent molecule model
Šklíba, Pavel ; Mašín, Zdeněk (advisor) ; Čížek, Martin (referee)
The aim of this thesis is to investigate theoretically photoelectron spectra of small water molecular clusters. This work is motivated by the recent experimental results of Hartweg et al [Phys. Rev. Letters 118, 103402, 2017] which showed that with an increasing number of constituent molecules in the water cluster the asymmetry parameter characterizing the photoelectron angular distribution converges to a universal shape. At the moment there are no theoretical calculations to support this finding. Therefore, we have developed a very simple model of photoionization of molecular clusters based on the use of photoionization data for a single molecule. We have found that the results of our model are sensitive to the different conformations of the clusters. Some of our results for the photoelectron angular distribution exhibit trends observed in the experiment. Nevertheless, the validity of our model will have to be studied in the future with the help of accurate calculations before the results can be conclusively interpreted.
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Crystal and molecular structure study of garnets from selected localities of the České středohoří Mts.
Píšová, Barbora ; Skála, Roman (advisor) ; Laufek, František (referee)
Major and minor element contents of garnets from mantle peridotites and eclogites brought to the surface by volcanic rocks of the České středohoří Mts. were determined by an electron probe microanalyzer. Garnets are homogenous and their chemical composition corresponds to solid solution containing 65-71 % pyrope, other end members significantly present are almandine, uvarovite and grosulare. This method also help to discover polyphase inclusions chemically corresponding to amphiboles (pargasite, cummingtonite, magnesio-hornblende and katophorite). Next to amphiboles following minerals were found in inclusions: omphacite, carbonates, phlogopite, clinochlore, olivine, apatite, spinel group minerals, and sulfidic phases potentially close to pentlandite. Samples were also analyzed by powder X-ray diffraction. Qualitative phase analysis confirmed pyrope homogeneity. The refinement of crystal structure parameters was performed by the Rietveld method. Raman microspectroscopy showed shifts of individual bands in the Raman spectra compared to those of pure pyrope. Position of bands in spectra differs due to the substitution of Ca for Mg at the dodecahedral sites of the structure. Mutual positive correlations among elements Cr, Ca, Mg, Al, Si, Mn, Ti and Na were observed. Correlations were found also between...
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Studies of Lanthanide Complexes by a Combination of Spectroscopic Methods
Krupová, Monika ; Bouř, Petr (advisor) ; Kapitán, Josef (referee)
Studies of Lanthanide Complexes by a Combination of Spectroscopic Methods Monika Krupová (Department of Physical and Macromoecular Chemistry, Faculty of Science, Charles University in Prague) Since conventional structural analysis offers rather limited means for the chirality detection, a series of lanthanide tris-(β-diketonates) are investigated as effective receptors for a better chirality sensing in biomolecular substrates. These lanthanide complexes containing β-diketonate ligands are electrically neutral; they can further coordinate with various small organic molecules such as chiral alcohols, amino alcohols or amino acids in organic solvents and produce a strong chiral signal. Previously, a resonance in Raman scattering was observed in the studied systems due to the correspondence of europium electronic transition energy to the laser excitation wavelength, about a 100-fold signal enhancement if compared to non-resonant vibrational ROA was observed. This enabled shorter detection times as well as lower sample concentrations. In the current work, interaction of the Eu(FOD) complex with (R)- and (S)- enantiomer of 1-phenylethanol in n-hexane was studied using IR spectroscopy, Raman spectroscopy and Raman optical activity (ROA), UV-Vis spectroscopy and ultraviolet circular dichroism (UVCD). Only...
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Comparison of effectiveness of teaching using computers vs. 3D models
Andělová, Denisa ; Janštová, Vanda (advisor) ; Jáč, Martin (referee)
Currently, pupils' interest in science continues to decline, although this area of education is very important in every day life (medicine, environment, etc.) and there is high demand for science professions on the labor market. Molecular biology curriculum concerning DNA and the transfer of genetic information is abstract and difficult topic for pupils to imagine, and for teachers to explain. There are many ways to teach this topic. Very popular are iquiry and laboratory practise. But not all schools have their own laboratories, and can teach molecular practical effectivelly. Inquiry based teaching is time consuming to prepare, and not every topic is appropriate to be taught this way. Another possibilities how to visualize "invisible" molecules and processes are computer software and animations or 3D physical model. In my thesis, I examined the effect of using computers and animations to teach abou DNA compared to using a 3D physical model on students' knowledge. I laso tested the possible influence of gender and pupils' preferences on their achieved score on knowledge tests. The research was performed in five classes at three high schools in Prague. Students in year 12 were on different types of high school and some of them took special biology class, their age was between 15 and 18 years. The...
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