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Advanced material based on secondary raw materials for construction of subgrade layer
Hrubý, Jakub ; Luňáček,, Martin (referee) ; Černý, Vít (advisor)
The diploma thesis deals with the development of a new material for the establishment of a layer of the ground body of a railway undercarriage purely on the basis of secondary raw materials. The theoretical part presents the characteristics of structural layers, materials used for bonded substrates, including their requirements. The following are the general conditions for the creation of base layers from purely secondary raw materials and previous experience with the issue. The introduction of the experimental part of the thesis sets out the basic parameters of secondary raw materials (construction recyclates, waste from railway bed cleaning, dust from cement plant) and energy by-products (fly ash, coal slag and municipal waste incinerator), which together form the raw material base. Grain size, absorbency, moisture, bulk density, chemical analysis and pollutant content were determined on the raw materials. Bulk densities and compressive strengths of the bonded mixtures were determined. The optimum humidity of all mixtures was determined by the Proctor standard test. Experimental verification was performed on testing of bonded mixtures in order to verify the effect of cement dose, when the original dose of 8% was optimized for construction recycled and slag from municipal waste incinerator to 4%, due to high strengths ranging from 4.5 to 6.0 MPa. Further optimization also included the addition of an energy by-product in a proportion of 10% of the weight of the secondary raw material. At the end of the experimental part, two optimal recipes were selected (recycled concrete with 4% cement and 10% fluid fly ash; slag from a municipal waste incinerator with 3% cement and 10% fluid fly ash), which underwent advanced testing in the form of frost resistance and resistance to water and a functional sample was designed. The final functional sample is recycled concrete with cement and 10% addition of fluid fly ash, which is suitable for core layers without frost loading.
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Methanol as an alternative fuel
Balcárek, Ondřej ; Kučera, Pavel (referee) ; Píštěk, Václav (advisor)
This Bachelor thesis is a topic review of problematics of alternative fuel solutions, in particular of methanol and it's production. The aim was to describe properties and possibilities of use of methanol, not only as fuel, but also as a raw material in chemical industry. The information was obtained mainly from English-written sources. Finally, in conclusion part, use and potential of methanol in period of transition to renewable sources is being reviewed.
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Repair of a holder for grinder cover
Židlický, Ondřej ; Prokop, Jaroslav (referee) ; Kalivoda, Milan (advisor)
This Bachelor thesis is focused on the repair of a holder for a grinder cover and the manufacture of the missing pieces of a pedestal grinder. The structurally-functional analysis of the machine and the manufactured pieces is described in the first chapter of this thesis. The manufacturing process itself is described in the following chapters. Raw materials and production technology are designed for the manufactured components. For each component, there are described the technological processes and instructions. The junction of the new parts of the machine with the original ones is conducted through welding. After this operation, the whole grinder cover is sandblasted and its surface is sprayed with a protective layer of lacquer. Next, the grinder cover is mounted to the pedestal of the grinder. The whole manufacture design is considered from the technological and economical point of view in the penultimate chapter and the drafts for improvements are described in the last chapter. All of the components are manufactured in accordance with the design and the grinder is once again in good technical condition.
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Aktuálna problematika zrenia mäsa vo vzťahu k očakávaniam a požiadavkám zo strany spotrebiteľa
Gago, Branislav
This work investigates the effect of aging on meat quality. The research is based on a review of current scientific literature, including studies on biochemical and sensory changes that occur during aging. In particular, i compared the effects of aging on marbling, tenderness, flavor and moisture content. Further, the effects of different aging processes such as dry aging and wet aging were discussed. In addition, the economic and health benefits of aged beef were also investigated. The results showed that aging can have a positive effect on the quality and flavor of the meat, leading to increased tenderness and marbling, as well as improved flavor and juiciness. Additionally, dry aging has been found to be more effective in increasing beef quality compared to wet aging. Finally, the economic and health benefits of ripening were emphasized.
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Identifying the materials in archaeological textiles
Březinová, Helena ; Pechočiaková, M. ; Grabmüllerová, J.
Given their organic origin, textiles rank among the rarest archaeological finds. While the vast majority of these artefacts are preserved as small fragments or mineralised remnants, their detailed textile technology study provides interesting and important information about the use of textile techniques and the quality of processing. The most important information concerns the utilised textile materials, but for degraded textiles, these materials are among the most difficult information to obtain. Image analysis using electron microscopy (SEM) is a significant aide in this pursuit.
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Porovnání výrobní linky s jednošnekovým a dvoušnekovým extrudérem
BRŮŽEK, Vojtěch
The main goal of the thesis is to compare the technologies of the single-screw and twin-screw extruder. Description of individual technologies and extrusion lines. Comparison in terms of raw material processing, wear of functional parts, performan-ce and financial expenses. Last but not least, the work will serve to deepen the know-ledge and innovations of the issue.
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Advanced material based on secondary raw materials for construction of subgrade layer
Hrubý, Jakub ; Luňáček,, Martin (referee) ; Černý, Vít (advisor)
The diploma thesis deals with the development of a new material for the establishment of a layer of the ground body of a railway undercarriage purely on the basis of secondary raw materials. The theoretical part presents the characteristics of structural layers, materials used for bonded substrates, including their requirements. The following are the general conditions for the creation of base layers from purely secondary raw materials and previous experience with the issue. The introduction of the experimental part of the thesis sets out the basic parameters of secondary raw materials (construction recyclates, waste from railway bed cleaning, dust from cement plant) and energy by-products (fly ash, coal slag and municipal waste incinerator), which together form the raw material base. Grain size, absorbency, moisture, bulk density, chemical analysis and pollutant content were determined on the raw materials. Bulk densities and compressive strengths of the bonded mixtures were determined. The optimum humidity of all mixtures was determined by the Proctor standard test. Experimental verification was performed on testing of bonded mixtures in order to verify the effect of cement dose, when the original dose of 8% was optimized for construction recycled and slag from municipal waste incinerator to 4%, due to high strengths ranging from 4.5 to 6.0 MPa. Further optimization also included the addition of an energy by-product in a proportion of 10% of the weight of the secondary raw material. At the end of the experimental part, two optimal recipes were selected (recycled concrete with 4% cement and 10% fluid fly ash; slag from a municipal waste incinerator with 3% cement and 10% fluid fly ash), which underwent advanced testing in the form of frost resistance and resistance to water and a functional sample was designed. The final functional sample is recycled concrete with cement and 10% addition of fluid fly ash, which is suitable for core layers without frost loading.
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Methanol as an alternative fuel
Balcárek, Ondřej ; Kučera, Pavel (referee) ; Píštěk, Václav (advisor)
This Bachelor thesis is a topic review of problematics of alternative fuel solutions, in particular of methanol and it's production. The aim was to describe properties and possibilities of use of methanol, not only as fuel, but also as a raw material in chemical industry. The information was obtained mainly from English-written sources. Finally, in conclusion part, use and potential of methanol in period of transition to renewable sources is being reviewed.
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