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Preparation of hystorical geopolymers
Šrámková, Eva ; Šoukal, František (referee) ; Havlica, Jaromír (advisor)
Diploma thesis studies historical bonding agents on the base of geopolymers. The aim of the thesis is to find a proper material composition, especially made of natural clay materials (kaolinite, bentinite) and their modifications (metakaoline). These bonding agents have to have a suitable type of an activator that guarantees good bonding properties. Therefore testing of various kinds of alkaline activating ingredients on the same mineral composition was done. Except of usual hydroxides and a water glass, ancient natrons (mixtures of alkaline carbonate with addition of appropriate chlorides) and a lime mash were used as the activators. From the above mentioned mixtures, series of samples (columns 20 x 20 x 100 mm) stored at the laboratory temperature were prepared. In the prepared mashes, their workableness and moulding were investigated. In the developed samples, their surface appearance was observed together with a number of efflorescence and its types. An indivisible part of the research was formed by determination of mechanical properties of the experimental columns such as a compressive strength and a tensile strength in bending. Furthermore, phase composition of the samples and its changes with a temperature increase were investigated. For these tests, XRD and TG – DTA methods were used. A multi-seat isoperbolic calorimeter was used to study hydratation that was also the important part of the general evaluation of designed mixtures.
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Surface treatment by wet paiting
Fical, Karel ; Žák, Ladislav (referee) ; Kubíček, Jaroslav (advisor)
Protection of various coating materials is today very important, both in terms of aesthetic, functional and, especially corrosion. Corrosion annually causes significant damage to metal structures and degradation of material can cause a total damage of the parts or the whole structure. When appropriate choice of coating materials can suppress the corrosion and its manifestations delay up to several years. Today, the protection of organic material coats the most common way and takes 80 to 90% of all coatings. When selecting paints and their subsequent applications we care about the material properties of the edit, its functional use, the environment in which they will be located and the properties of paint itself. To achieve satisfactory properties, it is necessary to create a technological process for the specific case.
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Recyclation of dust from production of dry mortar blends
Ondrůšková, Nela ; Novotný, Radoslav (referee) ; Šoukal, František (advisor)
The work deals with the problem of disposal of ever-increasing waste (dust) from the production of building materials and examines the possibility of recycling dust dust into cement repair mortar. The aim of this work was to determine the composition of individual dust particles from the production of cement mixtures and to determine their mechanical properties, as well as to determine the ideal ratio of dust particles to each other when mixing the dust mixture and its mechanical properties. This mixture consisted mainly of dust from products based on Portland cement, aluminous cement, gypsum and lime hydrate. The mixture further replaced part of the cementitious mortar and the impact of the additive on the mechanical properties of the cementitious mortar was determined. X-ray fluorescence spectrometry was used to determine the elemental composition, and X-ray diffraction analysis was used to determine the mineralogical composition. Test specimens were prepared according to the ČSN EN 12390 standard. Mechanical strength tests were performed on the test specimens. A large part of the test specimens could not be subjected to mechanical tests because the test specimen did not solidify even after a long time. The individual measurements that could be made show that the mechanical properties of the dust samples show values which have shown that the dust cannot be recycled into the product due to its instability. Dust particles have too diverse composition and in combination with cementitious repair mortar do not have the required properties. The problem is especially the sampling from the data, which did not solidify at all and thus excluded the remaining samples with already good properties of the same sample. When designing the method of recycling, it was necessary to take into account which product of the company is most in demand, where recycling would also make economic sense, which is also an important indicator for the operation of the company today. Dust particles could prove successful in another product, but it would not be advantageous for the company now, so now the recycling of dust particles will not start and they will be further disposed of in the same way.
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Research in the Field of Anhydrite Binders
Břicháčková, Jana ; Smetanová, Lenka (referee) ; Gazdič, Dominik (advisor)
The presented work deals with research in the field of sulfate binders on the anhydrite base. Conceptually, it is divided into a general theory of sulfate binders and anhydrite mortar compounds, which is describing in detail the using of anhydrite mortar compounds on the poured floor screeds, and then the experimental part, where is made the mineralogical analysis of seven different gypsum resources and subsequent is monitored the effect of two sulfate exciters on the achieved technological properties and hydration process.
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Study of electrode materials for post-lithium ion systems
Kekelák, Miroslav ; Jaššo, Kamil (referee) ; Kazda, Tomáš (advisor)
This bachelor thesis deals with studying electrode materials for post-lithium ion systems. The theoretical part describes the principle, history and construction of lithium-ion battery cells. A separate chapter is dedicated to the materials of positive and negative electrodes for lithium-ion batteries. The third chapter is dedicated to the principles of new generation lithium-air and sodium-ion batteries. The last chapter of theoretical part is dedicated to lithium-sulfur batteries, which describes their principle, history, used electrode materials and the influence of binders. The experimental part is dedicated to the preparation of the electrode material of lithium-sulfur accumulator in combination with water-soluble binders and their measurement using electrochemical methods.
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Rheological properties of building binders in their fresh state
Hegrová, Michaela ; Rovnaník, Pavel (referee) ; Vyšvařil, Martin (advisor)
This thesis is devoted to the rheological properties of building binders. The theoretical part focuses on individual types of building binders, their rheological properties and basic parameters determinated during the rheological characterization of building binders. The practical part deals with the resultes obtained from the meansurements on a rotational rheometr using the geometry type of plate to plate. These results are subsequently evaluated.
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Study of anhydrite binder
Břicháčková, Jana ; Fridrichová,, Marcela (referee) ; Gazdič, Dominik (advisor)
The present work deals with research in the preparation of sulphate anhydrite binders based. It is conceptually divided into a general theory of sulphate anhydrite binders and binders, focusing in particular anhydrite cast floors, as well as search anhydrite binders of research training at the Institute of THD and study requirements for screed materials, with emphasis on anhydrite screed mix.
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New possibilities of using secondary raw materials for the renewal of the railway substructure
Buřičová, Karolína ; Luňáček,, Martin (referee) ; Drochytka, Rostislav (advisor)
The work is devoted to new possibilities for the recovery of secondary raw materials and track bed waste with a combination of both suitable and unsuitable soils. The aim of the thesis is to develop a new functional sample suitable for the recovery of a substructure of railways based on secondary raw materials. The theoretical part addresses the issue of the use of soil and secondary raw materials as the base layers of railway structures, and is focused on the possibilities of soil adjustments or enhancement. The practical part is focused on the analysis and selection of potentially suitable raw materials, the design of new raw material mixtures containing concrete recyclables, waste from cleaning the auto mixer and waste from cleaning the rail bed. Further, to modify the mixtures designed with fluid ash from biomass combustion to achieve higher toughness. Then they will be experimentally verified and based on the results the optimal formula for use in the solid of the railway bottom will be determined. Final optimal recipe achieving basic required parameters for use in active zone without the requirement for frost resistance and ecology is composed of 30 % of F4-CS, 4 % of portland cement CEM II-B/LL, 3 % of lime hydrate, 70 % of recycled concrete and 10 % of fluid ash from biomass combustion.
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