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Optimalisation of coposite materials for civil engineering
Kazda, Tomáš ; Chladil, Ladislav (referee) ; Novák, Vítězslav (advisor)
This work is focused on optimalisation of coposite materials for civil engineering. In the theoretical part of the project is introduction of the composite materials and materials which are used for their production. There are also concerned their properties and possible application areas. In conclusion of theoretical part this project is a summary of the possible use of composite materials. The practical part compares the characteristics of the different types of composites made in terms of conductivity and the rate of corrosion.
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Application of graphite in thermal management of microelectronics
Havlíček, Václav ; Mačák, Martin (referee) ; Vyroubal, Petr (advisor)
Tato práce je zaměřena na zlepšení tepelného managementu mikroelektroniky implementací materiálů na bázi uhlíku, přesněji grafitových fólií, do tepelné architektury mikroelektroniky. Práce začíná vysvětlením současných metod chlazení a výzev v oblasti mikroelektroniky. Poté přechází k běžně používaným materiálům - hliníku a mědi a přidává do výběru i uhlíkové alotropie. Ve druhé části tato práce obsahuje několik příkladů použití pyrolytické grafitové fólie v tepelném managementu mikroelektroniky, prokazuje jeho použitelnost a analyzuje přínosy pro šíření tepla, tepelnou vodivost při dodržení elektrické izolace a možné využití ve flexibilní elektronice.
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Using lead-acid accumulators in hybrid electric vehicle regime
Hejdiš, Roman ; Novák, Vítězslav (referee) ; Bača, Petr (advisor)
The master´s thesis discuss characteristics of hybrid electric vehicles and lead-acid accumulators applied in car industry. It compares classic and alternative drive in cars, descibes classification of hybrid drives and its characteristics. Further work disscus lead-acid accumulators which focuses on VRLA accumulators applied in hybrid electric cars. Practical part contains a construction description of negative electrode and experiment, which studied influence of various amount addition of carbon on attributes of these electrodes.
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The modification of the graphene structures by low energy ions (E
Maniš, Jaroslav ; Čermák,, Jan (referee) ; Mach, Jindřich (advisor)
Diploma thesis deals with the influence of low energy ions on graphene structures. Graphene structures were modified by nitrogen and argon ions of energies lower than 100 eV. Modified structures were analysed by Raman spectroscopy and x-ray photoelectron spectroscopy. The influence of the dose of ions on quality of graphene were investigated as well. In addition, this diploma thesis includes the literature search which focuses on modification of graphene by charged particles.
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Desing of the carbon cap for the bike's fork
Gallo, Dominik ; Skřivánková, Vendula (referee) ; Košťál, David (advisor)
This bachelor's thesis discusses problems and solutions of design of the carbon crown for the bike's fork. It shows an overview of the possible implementation of the initial design up to final part. The output will be the crown made of carbon composite by mould pressing. For manufacturing the prototype form will be used 3D printing – Fused Deposition Modeling.
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Expanded Grpahite as Negative Electrode Material for Aporotic Intercalation Systems
Kaňa, Michal ; Čech, Ondřej (referee) ; Libich, Jiří (advisor)
This thesis deals with lithium-ion batteries. It focuses primarily on the materials which are the basis of negative electrode materials, especially on natural expanded graphite. The aim of this thesis is delineate problems of lithium-ion batteries and the possibilities how to improve their basic parameters such a capacity and current carrying capacity. The first part focuses on the description of the functionality of a lithium-ion battery. The second part focuses on the production of negative electrodes, measuring their properties and characteristics. In the last part, there are evaluated and compared individual negative electrode in the role of host of lithium and sodium ions according to the obtained data and then there are the conclusions draw
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Electrochemical properties of negative electrode made from natural and expanded graphite
Priščák, Juraj ; Máca, Josef (referee) ; Libich, Jiří (advisor)
This bachelor thesis deals with lithium-ion accumulators from the prespective of its structure, operation and using. It studies anode materials, focusing on natural and expanded graphite. Explains operation and structure of lithium-ion accumulator. The second part of thesis aims on manufacturing of anode electrodes of natural and expanded graphite. Deals with their measurement of its current a capacity rating. The aim of the thesis is how characteristic of accumulator depends on features of anode materials. In conclusion is sum up and comparation both materials on base of their measurement.
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Materials for the construction of frames of gravity bicycles
Hrubý, Erik ; Ročňáková, Ivana (referee) ; Juliš, Martin (advisor)
The presented bachelor thesis in it first part is focuses to the application of special racing bikes. The less known gravity disciplines with an explanation of their nature, the type of track and rules are presented. The second part of thesis deals with the structural design and fitting of mountain bikes used in each presented gravity disciplines. In the last part of thesis is a list of structural materials from which are manufactured special bike frames focusing on their mechanical properties, advantages and disadvantages and other usage.
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Porovnání množství vázaného uhlíku v nadzemní i podzemní biomase v různých typech využití půdy v okolí města Oxapampa, Peru
Chalupová, Karolína
The present work compares amount of sequestered carbon in different types of land use in the vicinity of Oxapampa in Peru. Research was conducted in the autumn of 2022 with focus on three main types of land use: coffee agroforestry plantations, montane tropical forests and silvopastoral systems. Data collection was carried out with Field-Map technology, where 47 study plots on 6 transects were compared. To estimate aboveground and belowground biomass allometric equations were used. The evaluation of soil carbon stocks was determined based on soil analysis using a Soli-TOC device (Elementar). The results showed that there was no statistically significant difference between the amount of carbon bound in the biomass of agroforestry coffee plantations and forest ecosystems. Soil carbon stocks were highest in forest stands in the upper soil layers. At lower depths (20–30 cm) the difference between the studied ecosystems was no longer registered. Average soil carbon values (%) for coffee agroforestry systems and particular depths were as follows: H (7,6 ± 3,8); 0–10 (5,1 ± 1,8); 10–20 (3,8 ± 0,8); 20–30 (3,4 ± 0,7). For study plots in forest ecosystems: H (34,2 ± 12,1); 0–10 (22,4 ± 14,7); 10–20 (9,5 ± 6,2); 20–30 (7,3 ± 5,8). Soil carbon stocks values for silvopasture systems were: H (12,1 ± 4,7); 0–10 (7,3 ± 3,3); 10–20 (5,3 ± 2,3); 20–30 (3,7 ± 2,1).
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Pedodiverzita vybraných ekotonů na přechodu lesní porost - palouk na území Školního lesního podniku Masarykův les Křtiny
Bydžovský, Radek
Ecotones and their environments are often referred to as areas of significant diversity that condition the interactions of neighbouring ecosystems. Manifestations of ecotone community diversity can be observed, for example in the species composition of flora and fauna. However, this bachelor thesis examines the characters of the soil environment of this ecosystem and compares it with enviroment of a forest and a meadow. Evaluated soil diversity parameters are active and potential soil reactions, soil catalase enzyme aktivity, C, N, S element content and possible carbonate content. The evaluation of these soil characteristics was carried out in the three selected sites. The significant dynamics of the ecotone environment was confirmed in the case of soil reaction. Catalase also showed different activity rates in the ecotone area. A similar finding was confirmed in the case of the analysed elements C, N and S. Based on the evaluated parameters, the ecotone area shows a significant different character of the soil environment. However, the character and degree of manifestation in ecotone area are very closely linked to the characteristics of the individual habitats.
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