|
|
Company Development Strategic Framework Proposal with Emphasis on Product Portfolio
Coufal, Denis ; Vozka, Jiří (referee) ; Zich, Robert (advisor)
The purpose of this diploma thesis is a strategic development proposal for a Czech electrotechnical company with an emphasis on a product portfolio. The theoretical basis of this thesis serves as a structure for the analytical and the proposal part. Outputs of the external and internal analysis are the bedrock for formulation of strategic product portfolio development framework at the corporate and business level. The proposal provides a company with a framework for strategic behavior focused on better competitive ability, product portfolio expansion, and delivering higher value for customers of energetic engineering.
|
|
| |
|
|
Chemical Experiments in Secondary Education
Vozka, Jiří ; Klímová, Helena (advisor) ; Hybelbauerová, Simona (referee)
The thesis contains four topics from organic chemistry and biochemistry processed into the structure of chemical experiments and laboratory works. These topics are Proteins, Light and fire, Curiosities and Professions. Some experiments are accompanied by motivational text, including additional information or interesting facts. Each experiment was verified in the laboratory at the Department of Teaching & Didactics of Chemistry, Faculty of Science, Charles University in Prague. Each experiment was photographically documented. Two of them were also video taped and these videos with all pictures are on the CD accompanying this thesis.
|
|
| |
|
|
Characterization of new chiral separation systems for HPLC
Vozka, Jiří ; Tesařová, Eva (advisor) ; Sýkora, David (referee) ; Petr, Jan (referee)
The dissertation thesis is focused on the physico-chemical characterization of interaction mechanisms of chiral stationary phases based on derivatized cyclofructans. Correct interpretation of retention and enantiodiscrimination processes substantially facilitates the development and optimization of new enantioselective methods using cyclofructan-based chiral stationary phases. At first, the interaction mechanisms of three commercially available cyclofructan-based stationary phases were studied in normal-phase mode of liquid chromatography. Namely, systems using chiral stationary phases based on dimethylphenyl carbamate cyclofructan 7, R-naphtylethyl carbamate cyclofructan 6 and isopropyl carbamate cyclofructan 6 were studied. Linear free energy relationship model was used as a basic tool for characterization of interactions on the stationary phases. The mentioned model revealed that the main interactions contributing to retention in cyclofructan-based systems are hydrogen bond acidity and dipolarity/polarizibility, while dispersion interactions cause decrease of retention. The impact of oligosaccharide skeleton of the cyclofructan selector on the enantioselectivity was elucidated by the comparison with seemingly analogous cyclodextrin-based chiral stationary phases. Cyclofructan-based chiral...
|
|
|
Characterization of new chiral separation systems for HPLC
Vozka, Jiří
The dissertation thesis is focused on the physico-chemical characterization of interaction mechanisms of chiral stationary phases based on derivatized cyclofructans. Correct interpretation of retention and enantiodiscrimination processes substantially facilitates the development and optimization of new enantioselective methods using cyclofructan-based chiral stationary phases. At first, the interaction mechanisms of three commercially available cyclofructan-based stationary phases were studied in normal-phase mode of liquid chromatography. Namely, systems using chiral stationary phases based on dimethylphenyl carbamate cyclofructan 7, R-naphtylethyl carbamate cyclofructan 6 and isopropyl carbamate cyclofructan 6 were studied. Linear free energy relationship model was used as a basic tool for characterization of interactions on the stationary phases. The mentioned model revealed that the main interactions contributing to retention in cyclofructan-based systems are hydrogen bond acidity and dipolarity/polarizibility, while dispersion interactions cause decrease of retention. The impact of oligosaccharide skeleton of the cyclofructan selector on the enantioselectivity was elucidated by the comparison with seemingly analogous cyclodextrin-based chiral stationary phases. Cyclofructan-based chiral...
|
|
|
Evaluation of the Financial Situation in the Company and Proposals to its improvement
Coufal, Denis ; Vozka, Jiří (referee) ; Fojtů, Kateřina (advisor)
The purpose of this bachelor‘s thesis is the evaluation of the financial situation in the selected company in the period from 2014 to 2018 and proposals to its improvements. The theoretical part defines concepths of financial analysis and financial ratios. The practical part puts methods from the previous part in use and calculates individual financial ratios. The final part presents proposals and recommendations to improve the financial situation of the selected company.
|
|
|
Sulfobutylether-β-cyclodextrin as a chiral selector for separation of amino acids and dipeptides in HPLC
Procházková, Hana ; Kalíková, Květa (advisor) ; Vozka, Jiří (referee)
The main aim of this work was to prepare and characterize a new chiral stationary phase (CSP). The CSP was prepared by dynamic coating of sulfobutylether- β-cyclodextrin (SBE-β-CD) on a strong anion-exchange stationary phase (SP). The selectivity and stability of the newly prepared CSP were tested on the sets of chiral and achiral analytes. The next separation system used was composed of C18 SP with the addition of SBE-β-CD as a chiral selector into the mobile phase. The set of chiral analytes contained amino acids phenylalanin, tyrosine, tryptophan, their derivatives and dipeptides glycine-DL-tryptophan and glycine-DL- phenylalanin. Four groups of mixtures of blocked and unblocked dipeptide isomers were tested for achiral separations. Dipeptides used for the mixtures had the same molecular formula but the sequence of amino acids was reversed. Measurements were carried out in reversed phase separation mode and hydrophilic interaction liquid chromatography. Mobile phases composed of methanol as an organic modifier and four different aqueous parts: (i) deionized water, (ii) aqueous solution of formic acid (pH 2.10), (iii) 20mM ammonium acetate buffer (pH 4.70) and (iv) 10mM ammonium acetate buffer (pH 8.80) in various volume ratios. Newly prepared SBE-β-CD CSP was more suitable for separations of...
|
|
|
Characterization of new chiral separation systems for HPLC
Vozka, Jiří
The dissertation thesis is focused on the physico-chemical characterization of interaction mechanisms of chiral stationary phases based on derivatized cyclofructans. Correct interpretation of retention and enantiodiscrimination processes substantially facilitates the development and optimization of new enantioselective methods using cyclofructan-based chiral stationary phases. At first, the interaction mechanisms of three commercially available cyclofructan-based stationary phases were studied in normal-phase mode of liquid chromatography. Namely, systems using chiral stationary phases based on dimethylphenyl carbamate cyclofructan 7, R-naphtylethyl carbamate cyclofructan 6 and isopropyl carbamate cyclofructan 6 were studied. Linear free energy relationship model was used as a basic tool for characterization of interactions on the stationary phases. The mentioned model revealed that the main interactions contributing to retention in cyclofructan-based systems are hydrogen bond acidity and dipolarity/polarizibility, while dispersion interactions cause decrease of retention. The impact of oligosaccharide skeleton of the cyclofructan selector on the enantioselectivity was elucidated by the comparison with seemingly analogous cyclodextrin-based chiral stationary phases. Cyclofructan-based chiral...
|
|
|
Characterization of new chiral separation systems for HPLC
Vozka, Jiří ; Tesařová, Eva (advisor) ; Sýkora, David (referee) ; Petr, Jan (referee)
The dissertation thesis is focused on the physico-chemical characterization of interaction mechanisms of chiral stationary phases based on derivatized cyclofructans. Correct interpretation of retention and enantiodiscrimination processes substantially facilitates the development and optimization of new enantioselective methods using cyclofructan-based chiral stationary phases. At first, the interaction mechanisms of three commercially available cyclofructan-based stationary phases were studied in normal-phase mode of liquid chromatography. Namely, systems using chiral stationary phases based on dimethylphenyl carbamate cyclofructan 7, R-naphtylethyl carbamate cyclofructan 6 and isopropyl carbamate cyclofructan 6 were studied. Linear free energy relationship model was used as a basic tool for characterization of interactions on the stationary phases. The mentioned model revealed that the main interactions contributing to retention in cyclofructan-based systems are hydrogen bond acidity and dipolarity/polarizibility, while dispersion interactions cause decrease of retention. The impact of oligosaccharide skeleton of the cyclofructan selector on the enantioselectivity was elucidated by the comparison with seemingly analogous cyclodextrin-based chiral stationary phases. Cyclofructan-based chiral...
|
guest ::
