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The Role of Ferrous Sulphate as a Setting Regulator and a Portland Clinker Reduction Agent
Mončeková, Miroslava ; Rovnaníková, Pavla (referee) ; Drábik, Milan (referee) ; Havlica, Jaromír (advisor)
In 2003, the European Community Obligation (directive 2003/5C/EC) regulates a maximal value of soluble hexavalent chromium to 0.0002 % (per weight of dry cement). This limitation leads to modifications of the regular Portland cement by using of suitable reduction agents. Therefore, the possibilities of chromium reduction become a very actual topic. The primary goal of this work is a basic research of the ferrous sulphate influence on hexavalent chromium reduction and also its influence on Portland clinker hydration process. The reduction ability was determined by UV/VIS method. The mechanism and ferrous sulphate influence on Portland clinker hydration process was observed by isothermal calorimetry and mechanical strength tests. XRD method, SEM-EDS analysis and Raman microscopy were used for identification of formed hydration products. Study of hydration mechanism occurring in this system was focused on the divergence observations from the regular Portland cement hydration. Pore solution analysis provided significant information about chromium behavior during the hydration process (substitution and releasing). Chromium incorporation into structure of hydration products during the reduction process was also studied in the pure tricalciumaluminate system with targeted Cr6+ content. This work suggests the possible substitution of the trivalent and hexavalent chromium into structure of monosulphate (AFm) phase.
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Visual Representation of Pi-Calculus Expressions
Prokopová, Dagmar ; Křivka, Zbyněk (referee) ; Rychlý, Marek (advisor)
This work deals with the problem of visual representation of Pi-calculus expressions. The theoretical part of this paper discusses general principles of process algebras as well as specific properties of individual models, with a focus on Pi-calculus. Also included is the comparison of several text and graphical representations of expressions. The main part of the thesis deals with the design and implementation of an application for converting text representation of expressions into graphical representation. In addition to the text and graphical representation, an internal tree representation designed to work with expressions within the application is also proposed. The thesis also describes algorithms for finding feasible reductions, performing reductions and expression simplification that operate with the proposed tree representation.
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Reduction of CentOS operating system
Kluka, Peter Milan ; Jablončík, Lukáš (referee) ; Komosný, Dan (advisor)
Táto práca slúži ako podporný materiál pre predmet Sieťové operačné systémy a ako pomocný materiál pre realizáciu projektu v rámci tohto predmetu. Účelom tejto práce bolo vykonať redukciu operačného systému z hľadiska jeho veľkosti na disku. Zadaným operačným systémom bola Linuxová distribúcia CentOS Stream 8. Redukovaný operačný systém obsahuje grafický web prehliadač, PDF prehliadač dokumentov a je dostupný pomocou vzdialeného pripojenia SSH. Práca porovnáva veľkosti odporúčaných grafických rozhraní a aplikácií. Na základe analýzy bola vytvorená sada skriptov, ktorá zautomatizovala proces minimalizácie. Výsledná veľkosť redukovaného systému bola 678 MB.
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Noise of Aircraft Jet Engines
Szelke, Ludvík ; Vacula, Jiří (referee) ; Novotný, Pavel (advisor)
In my bachelor's thesis I try to present the noise sources of aero-jet engines. First, I introduce the reader to a brief history of the development of jet engines and the principle of jet engine function. Then I continue with general knowledge about noise itself, what it is measured by and what effects it has on our lives. This is followed by an analysis of the sources of jet engine noise, both theoretical and using a computer model. At the end of my thesis, I mainly discuss the possibilities of noise reduction for the sources, and also possible future developments.
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Interactions of essential amino acids with iron ions
Nadějová, Jana ; Karlíčková, Jana (advisor) ; Siatka, Tomáš (referee)
Charles University Faculty of Pharmacy in Hradec Králové Department of Pharmacognosy and Pharmaceutical Botany Candidate: Jana Nadějová Supervisor: PharmDr. Jana Karlíčková, Ph.D. Title of Thesis: Interaction of essential amino acids with iron ions Iron is an important trace element that is needed for the proper functioning of the body. Lack of iron, as well as an excess of iron, can lead to pathological conditions, so it is necessary to control the level of iron in the blood and in case of overloading the body with iron, its chelation can be considered a possible therapeutic tool. Chelators for these therapeutic purposes should be the body's own substance. Amino acids are therefore ideal candidates for the regulation of iron homeostasis in the body, so this thesis focuses on some of them. The individual amino acids are linked by a peptide bond to form proteins. Proteinogenic amino acids are divided into essential, which must be ingested through food, and nonessential, which the body can create on its own. The aim of this study was to compare the iron-chelating and iron-reducing activity of the essential amino acids L-histidine, L-methionine, and the nonessential amino acids L- cysteine, its dimer L-cystine, L-aspartic and L-glutamic acid. The research also included a substance derived from...
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Interaction of chalcones with transition metals II.
Šulcová, Martina ; Macáková, Kateřina (advisor) ; Mladěnka, Přemysl (referee)
Charles University in Prague Faculty of Phramacy in Hradec Králové Department of Pharmaceutical Botany Candidate: Martina Šulcová Supervisor: Assoc. Prof. Ing. Kateřina Macáková, Ph.D. Title of the diploma thesis: Interaction of chalcones with transition metals II. Copper is one of the essencial elements in human body which is involved in the functioning of many enzymes and metabolic pathways. Although it appears in trace amounts in the body, its functions are irreplaceable. However, the ion level must be kept in balance by the various mechanisms of the body. If there is an excess or deficiency of copper in the body, this condition can lead to the development of health issues. Chalcones are substances belonging to the group of flavonoids. Their polyphenolic structure does not have a closed ring C. Studies describe their anticancer, anti-inflammatory, antiviral, antidiabetic, antibacterial, antioxidant, immunosuppressive and other properties. Chosen substances in the group of dihydrochalcones (naringin dihydrochalcone, neohesperidin dihydrochalcone, phloretin, phlorizin) and chalcones (isoliquiritigenin, licochalcone A) were tested for their chelation and reduction activity of the copper ions in this diploma thesis. The activity was measured at different pH environments (7.5; 6.8; 5.5 and 4.5) and...
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Development of voltammetric methods for detection of phytosterols on carbon-based electrodes
Zelenský, Michal ; Schwarzová, Karolina (advisor) ; Fischer, Jan (referee)
The aim of this diploma thesis was to develop an electrochemical method for three phytosterols, namely stigmasterol β-sitosterol and ergosterol using voltammetry techniques on glassy carbon electrode and boron doped diamond electrode. The work builds on previous results, where it was shown that the electrochemical oxidation of phytosterols requires perchloric acid in acetonitrile. When this acid is used, a dehydration reaction occurs. Calibration dependences were measured here for all phytosterols in an environment with a water content of 0.43%. The stability of the signal with increasing distilled water content was further investigated. Then the calibration dependences in the increased water content were measured again. If we want to use HPLC-type separation techniques, we must first find out how the phytosterols will behave in this environment, and therefore the signal stability on the buffer content was investigated. The buffers used were phosphate and acetate buffer. Subsequently, the concentration dependence was measured in an environment with a higher content of phosphate buffer. Furthermore, the possibility of detecting two phytosterols at once was investigated. Key words: dehydration, glassy carbon electrode, boron doped diamond electrode, oxidation, phytosterols, voltammetry
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Development of electroanalytical methods for detection of bile acids possessing 7α hydroxyl group
Jelšíková, Kristýna ; Schwarzová, Karolina (advisor) ; Dejmková, Hana (referee)
This master's thesis contains a study of electrochemical processes of selected bile acids possessing 7 hydroxyl group (cholic, chenodeoxycholic and −muricholic). The measurements were performed on boron−doped diamond electrode in the non-aqueous medium of acetonitrile and perchloric acid (water content 0.55 %) by cyclic voltammetry. It is known that the electrochemical activity of 7 bile acids is increased by a dehydration reaction between perchloric acid and the 7 bile acid. The subject of the study was the stability of the voltammetric response of chemically activated bile acids in the region of negative potentials. It was found that the presence of oxygen in the measured solution is an important factor for obtaining the cathodic signal of 7 bile acids. It probably performs a regenerative function; the product of the electrochemical reduction is re-oxidized in its presence, which leads to an increase in the voltammetric response. At the same time, it is important that the direction of the scan in cyclic voltammetry first proceeds to positive values. A potential of +2.0 V (vs. Ag/AgNO3 in acetonitrile) must be reached for the HO● radicals to be formed. It is these radicals that presumably lead to the formation of the product(s) of bile acids electrochemical oxidation that can be subsequently...
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Pupils with different native language at Czech schools
HOUDKOVÁ, Klára
Bachelor thesis is focusing on current issues with education of pupils with different native language. Thesis focuses on solving language barrier and its reduction, which is the biggest problem in teaching the children with different native language. Text deals with pupil's characteristic, their integration to class collective, with problems, which can appear along with these pupils. Basically, this thesis explains every needed information related with teaching pupils with different native language from teachers' views. The goal is to find out the best way of reduction language barrier and suitable teachers' approaches.
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New Techniques for Compact Representation of Boolean Functions
Maťufka, Ján ; Holík, Lukáš (referee) ; Lengál, Ondřej (advisor)
Binárne rozhodovacie diagramy (BDD) reprezentujú Booleovské funkcie a sú značne využívané vo formálnej verifikácii, model checkingu, syntéze obvodov v CAD softvéroch, atď. S rastúcim počtom premenných ale (v najhoršom prípade) exponenciálne rastie aj veľkosť BDD. Cieľom tejto práce je vytvoriť kompaktný model reprezentácie Booleovských funkcií založený na automatoch. K dosiahnutiu tohto cieľa boli použité stromové automaty. Vkladaním stromových automatov so špeciálnymi vlastnosťami do štruktúry BDD je možné redukovať opakujúce sa vzory. Tento model dosiahol v priemere 10-20 % menšie počty uzlov v testovaných prípadoch v porovnaní so súčasnými modelmi. Používanie automatového prístupu umožňuje vytvárať vlastné automaty prispôsobené na redukciu konkrétnych vzorov, čím sa rozširujú možnosti tohto modelu a jeho potenciál na ešte lepšie výsledky.
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