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Combined Effect of Li, Cu and S Doping on Structure and Hydration of β Dicalcium Silicate
Sedlačík, Martin ; Bartoníčková, Eva ; Novotný, Radoslav ; Palovčík, Jakub ; Másilko, Jiří ; Staněk, Theodor ; Rybová, Alexandra
This study investigates the effect of Li, Cu and S on the structure and hydration of the beta modification of dicalcium silicate (β-C₂S). The doped β-C2S phase was prepared by burning beta-C2S with dopant sources. The structure of prepared β-C2S samples was examined using X-ray diffraction, scanning electron microscopy and infrared spectroscopy. Heat evolution during hydration was assessed by isothermal calorimetry. A positive effect on cement hydration was observed for several dopant combinations.
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Specifics of nutrition in hospice care
Turková, Jana ; Starnovská, Tamara (advisor) ; Novák, Ondřej (referee)
Introduction: Hospice palliative care is provided to patients in the terminal phase of life with the aim of ensuring quality of remaining life with an emphasis on their individual needs and wishes. An integral part of palliative care is nutritional care and ensuring the patient's adequate nutrition. The theoretical part of the thesis describes the principles, standards and concept of development of palliative care, and provides a comprehensive overview of the types and forms of hospice care currently provided in the Czech Republic, and concludes with a consideration of nutrition and hydration in the terminal phase of the disease. In the practical part, the results of the questionnaire study are processed and presented. Objective of the thesis: The main objective of my bachelor's thesis is to determine whether an individual approach is applied to nutrition in the inpatient care of a selected hospice. The secondary objective is to discover whether patients in inpatient hospice care are satisfied with the nutrition and meals provided. Methodology: The project deals with research into the inpatient care of St. Štěpán's Hospice in Litoměřice. The research is designed as a questionnaire study. The data source is my own semi-structured questionnaire with 30 questions; 15 questions are closed, 13...
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Effect of ground limestone addition on properties of cement-slag binder systems
Bílek, Vlastimil ; Másilko, Jiří (referee) ; Opravil, Tomáš (advisor)
This thesis deals with the effect of ground limestone addition on properties of cement-slag binder system. The evolution of compressive and flexural strength of binary and ternary systems (pastes), where 25 % of cement was substituted by one or two admixtures in different ratio, were determined and mutually compared. Granulated blast furnace slag and three different limestones were these admixtures. Two of that limestones were natural and one was prepared by a precipitation. For comparison, mixtures, where ash was added insted of slag, were prepared. The mechanism, by which finely ground limestone participates in hydration process, was studied by conduductometric measurements of systems simulating conditions in fresh pastes, and by TG-DTA method, which was used to determination of added limestone amount which remains in its original form and the amount which participates in the formation of hydration products.
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Preparation of modified tricalcium aluminate phases and study of their hydratation processes
Vávrová, Alžběta ; Koplík, Jan (referee) ; Másilko, Jiří (advisor)
This diploma thesis deals with the preparation of modified tricalcium aluminate phases using sodium ions, and the study of their hydration processes and products. The X-ray diffraction analysis, isothermal calorimetry, laser diffraction, and scanning electron microscopy with energy dispersion analysis were used to solve this task. The preparation of modified tricalcium aluminate phases using high temperature methods has been described in the experimental section. Furthermore, the X-ray diffraction analysis was used to determine the purity of the prepared phases and the scanning electron microscopy with energy dispersion analysis was used to define the volume of sodium. Laser diffraction was used to measure a particle size distribution in the individual phases. Subsequently, hydration of the pure phases was performed in an isothermal calorimeter. It was followed by hydration of phases in the presence of different gypsum content and then in the presence of saturated portlandite solution. Hydration of some samples was stopped in order to better understand the hydration process. Hydration products were studied by X-ray diffraction analysis. The obtained results were compared with each other and the influence of sodium ions on both the structure of the prepared phases and the course of hydration and its products has been discussed. The effect of adding different volumes of gypsum and portlandite on the course of hydration of the individual phases was also compared.
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Influence of surfactants and cosmetic polysaccharides on skin parameters and human skin microbiome
Pilipenco, Alina ; Hurčíková, Andrea (referee) ; Ilona,, Matějková (advisor)
The aim of this diploma thesis was to investigate the effect of surfactants and cosmetic polysaccharides on skin parameters and its microbiome. Three surfactants were tested to determine their effect: Sodium Dodecyl Sulfate (SDS), Cocamidopropyl Betaine (CAPB), Decylglucoside (DG). Distilled water was also used for comparison. For the next part of the experimental work were selected 6 polysaccharides: high molecular weight Hyaluronic Acid (HMW HA), very low molecular weight Hyaluronic Acid (VLMW HA), Sodium Caproyl Hyaluronate (CaproylHA), Sodium Carboxymethyl -Glucan (NaCMG), Schizophyllan and Glucomannan. For comparison, placebo and untreated control (only CAPB treatment) were also included in the tests. The first part of the work is a literature search on the assigned topic, which contains the following parts: skin anatomy and its biophysical properties, skin microbiome and its functions, description of used surfactants and polysaccharides. The experimental part is mainly focused on bioengineering methods for evaluation of skin parameters and qRT-PCR to determine the relative proportion of main bacterial species of skin microbiome. First, the effect on the CT gene of 16S rDNA was analysed, and Propionibacterium acnes and Staphylococcus epidermidis strains were selected for further analysis. In conclusion are presented an overview of all properties of selected substances and assessment of their application in cosmetics.
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The use and effectiveness of colostrum in cosmetics
Bartoňová, Klára ; Vítová, Eva (referee) ; Němcová, Andrea (advisor)
This thesis deals with efficiency of colostrum contained in cosmetics. The aim of study was to determine whether the colostrum contained in cosmetic preparations have any influence on the state of human skin. The theoretical part is a literary review and it deals with defining the basic concepts and phenomena, especially the colostrum, its composition and properties. There is also discussed the raw materials used for real samples preparation and efficiency evaluated on these samples. There are also described the methods used to evaluate cosmetic products. The practical part is focused on evaluating the influence of hydratation of prepared cosmetic products. The skin hydratation and transepidermal water loss was measured by MPA 5. Consumer tests are attached to this part. Chemical stability of these cosmetics is assessed in a special chapter.
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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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Influence of Zinc in Byproducts on Hydration and Properties of Blended Portlands Cements
Šilerová, Iva ; Palou, Martin (referee) ; Rovnaníková, Pavla (referee) ; Havlica, Jaromír (advisor)
The theme of this work is to monitor the effect of zinc on the properties of blended Portland cements. Zinc was tested in the form of two-soluble salts: Zn(NO3)22 H2O and ZnCl2 and a very slightly soluble compound ZnO. Blended cements were prepared by partial replacement with finely ground granulated blast furnace slag, high-temperature and fluidized bed combustion filter fly ash. Flow properties were studied on the prepared pastes. Impact on hydration reactions was examined by using of isothermal and isoperibolic calorimetry. Flexural and compressive strength were measured as mechanical properties of the prepared test specimens. The phase composition of the prepared composites and incorporation of zinc ions in the cement matrix via leaching tests and FTIR analyzes were also studied. Microstructure development of cement samples was tested by SEM analysis with EDS. Influence on ecotoxicity was also measured.
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Use of microcalorimetry in the study of hydration of biopolymers
Bola, Tomáš ; Smilek, Jiří (referee) ; Krouská, Jitka (advisor)
This master thesis deals with the using of microcalorimetry in the study of hydration of biopolymers. Lactose has been selected together with the other biopolymers although it is not among biopolymers but disaccharides. Selected biopolymers are alginate, dextrane, chitosan and hyaluronan of two molecular weights. Lactose has been selected for these purposes mainly because it is a model example to determine whether or not the reaction to moisture between the other samples and the saturated salt solution occurs. The biopolymer hydration study, as opposed to the commonly used perfusion calorimetry method using the possibility of measuring with adjustable moisture has been used an isothermal microcalorimetry method where at two constant temperatures the reaction of the sample to the different moisture released by the saturated salt solution was monitored.
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