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Low energy cements based on clinker phases
Šmeral, Miloslav ; Koplík, Jan (referee) ; Bartoníčková, Eva (advisor)
This thesis deals with low-energy cements and the effect of dopants on their hydration, specifically copper and sulfur. The theoretical part summarizes the general information about clinker minerals, their low-energy/low-carbon alternatives and sustainability in the cement industry. Additionally, possible synthesis of clinker minerals are described. In the experimental part, methods for the preparation of doped tricalcium aluminate and the analysis of the synthesized products are presented. The sulfur doped tricalcium aluminate had the highest hydration heat. On the other hand, copper doped tricalcium aluminate and tricalcium aluminate in combination of these dopants exhibited lower hydration heat. The presence of the dopants also affected the composition of the hydration products.
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Metabolic activity and possibilities of its prediction
Štrbík, Tomáš ; Pokorný, Jan (referee) ; Řehák Kopečková, Barbora (advisor)
Metabolic rate is a set of processes in the body that convert food into energy and building materials, allowing us to grow, move, and maintain health. Therefore, it is important, and in some cases of illness also necessary, to monitor this variable. Various methods have been developed to quantify metabolic rate. The most accurate results come from direct measurements, which are often unavailable or too expensive, and are therefore primarily used for medical and scientific purposes. As an alternative, estimation methods based on easily measurable variables offer a more practical approach in everyday practice. This work discusses the different methods of determining metabolic rate and the various factors that influence it. Finally, one of these estimation methods is applied to available data. After comparing the measured and estimated values, a MAPE value of up to 11% was achieved during the performed activity, while during rest, this value reached up to 154%.
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Higher Heating Value of Sewage Sludge
Mikluš, Michal ; Bělohradský, Petr (referee) ; Houdková, Lucie (advisor)
The thesis is focused on problems of thermal treatment of sludge from wastewater treatment plants. The main objective is to establish a formula for calculating higher heating value (HHV) and lower heating value (LHV) of sludge based on its chemical analysis. The work is divided into two main parts: The theoretical part deals with the characteristics of sludge, thermal treatment of sludge, it isn´t omitted higher heating value and lower heating value. The main topic of a practical part is formulation of eguations for HHV and LHV calculation. Chemical analysis of sludge samples were supplied by TÜV NORD Czech s.r.o., together with the values of HHV and LHV. The calculations were verified by the program MINITAB.
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Optimalization of Technological Properties of Cement Sand Mixtures
Burianová, Klára ; Jelínek, Petr (referee) ; Tegel, Michal (referee) ; Rusín, Karel (advisor)
The work deals with optimization of the technological properties of cement-sand mixtures. The main objective is to find the correct mixture of the individual components which contribute to the rapid solidification of the mixture, hence shorter dismantling. The content is also of a method of measuring and recording during the plasticity of the mixture. Also assessment of the velocity of hydration heat cement mixture in the initial stage of the solidification process in the course of the strength properties of the mixture. To assess these phenomena was used calorimetric method used for measuring hydration heat cement mixture. Further measurements plasticity mixtures and mechanical and physical methods for measuring the compressive strength with the help of a measuring instrument LRU-D.
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Synthesis, properties and product of hydration of strontium aluminate cement
Kocián, Karel ; Bartoníčková, Eva (referee) ; Ptáček, Petr (advisor)
This diploma thesis deals with non-traditional binder, which is strontium aluminate, with his preparation and hydration. The behaviour of binary and ternary mixtures of strontium-calcium-barium aluminates was also studied. These aluminates were prepared by firing an equimolar mixture of aluminum oxide and the appropriate carbonate. Samples prepared this way, including their mixtures, were characterized by analytical methods such as X-ray diffraction analysis (XRD), thermal analysis with evolved gas analysis (TG-DTA and EGA), scanning electron microscopy (SEM), infrared spectroscopy (IR) and calorimetry, with the greatest importance for the study of the hydration process.
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Development of Web-Based Computational Tool for Analysis of Microcalorimetry Data
Nedeljković, Sava ; Musil, Miloš (referee) ; Sumbalová, Lenka (advisor)
Proteins are organic molecules made up of amino acids which are present in all living organisms. They are the main building blocks of life. Study of protein stability has great application in pharmaceutical, biochemical and medical industries, which makes it in high demand. Stability of a protein and many other properties can be determined by observing its unfolding mechanisms. Differential Scanning Calorimetry (DSC) has proven to be a very precise method for this task. The main goal of this thesis is to improve functions of software CalFitter, which analyses data obtained from DSC experiments. The new functionality of the software enables it to automatically calculate initial parameters, which are needed for successful analyses.
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Changes of slag particles during its alkaline activation
Petrů, Ludmila ; Hrubý, Petr (referee) ; Bílek, Vlastimil (advisor)
This bachelor thesis deals with changes of slag particles during its alkaline activation. The altered parts of the slag as well as the course of the alkaline activation varies depending on the activator used, and therefore suspensions of blast furnace slag in sodium hydroxide, water glass, sodium carbonate and, for comparison, in water were prepared. Slag particles were isolated from these suspensions at selected time intervals (5 min, 30 min, 1 h, 2 h, 5 h and 24 h) for particle size analysis and evaluation of BET specific surface. After solidification, the microstructure of the samples was observed using an electron microscope. To better assess the reaction processes, the pore solution was isolated from the suspensions and its composition was analyzed using optical emission spectrometry in inductively coupled plasma. The hydration process was monitored using isothermal calorimetry.
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Development and design of a modular battery box.
Rozinek, Josef ; Buday, Vladimír (referee) ; Porteš, Petr (advisor)
Tato práce se zabývá problematikou battery packů. V první části popisuje návrh battery packu z hlediska volby baterií, jejich tvaru, velikosti, typu a konfigurace zapojení. Dále uvádí vliv těchto charakteristik na výkonnost battery packu a jeho spolehlivost. Zabývá se problematikou termálního managementu battery packů a jeho vlivu na životní cyklus baterií. V druhé části se zabývá praktickým návrhem konceptu battery packu pro Lithium-polymerové baterie. Kalorimetricky je zde zjištěno množství produkovaného tepla při vybíjení, které je poté využito v CFD simulaci chlazení článku.
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The effect of boron and its compounds on setting time of portland cement
Kratochvíl, Jiří ; Švec, Jiří (referee) ; Opravil, Tomáš (advisor)
The aim of this work is to study the influence of boron and its compounds, boric acid and borax, on hydratation of portland cement. The first part describes chemical composition of portland cement and reactivity of its components. The second part deals with hydratation of portland cement. The teoretical part ends with description of retardation of portland cement using gypsum or other sulphate options. The experimental part describes preparation of samples – cement paste – modified by addition of boron, boric acid and borax in diferent concentrations. Results are obtained by evaluation of calorimetric curves, mechanical properties and phase composition. The goal is to describe kinetics of targeted slowed down process of hydratation and to find such addition which would suspend setting of boron modified system entirely. Comparison of effects of each boron-containing compound is based on its concentration and on its kind.
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Study of hydration of biocolloids
Hývnarová, Lucie ; Sedláček, Petr (referee) ; Klučáková, Martina (advisor)
The subject of this master’s thesis was to examine the hydration properties of selected biocolloids. Specifically, humic substances (fulvic and humic acids), hyaluronic acids in three molecular weights, dextran and chitosan were investigated. Hydration properties of selected biocolloid substances were studied by various methods. The influence of water content during the dissolution of substances and the different time for which water acted on biocolloids were studied. Differential scanning calorimetry DSC measurements resulted in enthalpies and crystallization and melting points. Heat fluxes resulted in the use of perfusion calorimetry. TGA thermogravimetric analysis was used to determine the moisture content of the bioolloids used, after measuring the perfusion calorimeter.
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