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Single Atomic Catalysts
Závodný, Adam ; Švec,, Martin (referee) ; Čechal, Jan (advisor)
Single atom catalysts are prospective class of materials, which holds promises to reach the ultimate limit of improvement in catalyst performance, selectivity, lifetime and cost reduction. The ability to efficiently capture the adsorbates at the active sites is the key prerequisite for catalytic transformation to the products. In this respect, our experimental study aims to describe the interaction of gas molecules (H2O, CO, O2 and NO) with single metal atoms (Rh, Ir, Cu) on the magnetite surface employing scanning tunneling microscopy.
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Drum Machine for Musicians
Spáčil, Tomáš ; Fedra, Zbyněk (referee) ; Povalač, Aleš (advisor)
The aim of this work is to create a functional prototype of a drum machine with sound generating using a microcontroller. Introduction is devoted to general drum machine and an analysis of its parts, principle and basic modes of operation. The following chapter deals with the principle of digital signal processing and sound generation using a microcontroller. Part of this chapter is focused on mixing using compression methods. The core of this work is to design my own block structure and overall scheme of the drum machine with a description of the parts. Followed by analysis and implementation with theoretical and practical point of view. It is mainly about presentation and description of important parts of firmware codes, DPS design and another technical documentation useful for final prototype production. The conclusion contains a summary of the results with prezentation and discussion.
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Characterisation for the cold field-emission sources intended for electron microscopy
Vašíček, Martin ; Tománek, Pavel (referee) ; Grmela, Lubomír (advisor)
This work deals with the theoretical foundations of electron emission into vacuum, various types of emissions, focused on the cold-emission and Schottky emission and the principle of quantum tunneling. The next part deals with the technical implementation of electron sources with a detailed study of the methodology of laboratory production of cathodes by electrochemical etching and construction of electron microscopes, using field-emission sources. This work also contains methods for measuring, processing and evaluation of electrical characteristics of emission sources.
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Increase of robustness of communication architecture for remote spectroscopy
Cebo, Patrik ; Klus, Jakub (referee) ; Kaiser, Jozef (advisor)
This thesis deals with the design of new communication architecture of a device for remote laser spectroscopy. The conceptual model is based on the analysis of the state of the art systems for remote laser spectroscopy. Moreover, the advantages and disadvantages of custom electric buses and its failures in deployment are discussed within this thesis. The result of the work includes the design of new communication architecture supported by Ethernet standards. The next part of the thesis focuses on the customized stepper motor controller composition, which will resolve the theoretical findings arising from the analysis.
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Static solution of prefabricated hall
Koníček, Jakub ; Koláček, Jan (referee) ; Zich, Miloš (advisor)
The presented thesis deals with design and optimization of selected structural elements of high-load storage hall skeleton. As a basis for the solution is taken the structure of a real storage hall designed in the years 2017-2018. The structure is designed for minimum weight. For this reason, so-called D-regions are formed on the structure. For the solution of D-areas, general methods of solution, such as STM or nonlinear FEM analyses, are used in the thesis. In the final designed structural elements are compared to the original design of the hall. Thesis include static calculation of 24 m long roof beam V1, static calculation of 24 m long ceiling beam ST1, drawing documentation and technical report. Programs were used for the calculation: SCIA Engeneer 18.1, Idea StatiCa Beam10.1, Idea StatiCa Detail 10.1, RIB Fermo, PTC MathCad and MS Excel.
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Connecting the TV studios
Flimel, Peter ; Křepelka, Václav (referee) ; Filka, Miloslav (advisor)
In this bachelor thesis work is done TV link study in 2020, for the purpose of mediation football matches between studies in Prague and Bratislava. This work deals with optical connections and technology matters to revel in the transmission of large amounts of data.
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Metal-organic networks on graphene surfaces
Kurowská, Anna ; Průša, Stanislav (referee) ; Čechal, Jan (advisor)
Molecular self-assembly is a spontaneous association of molecules and atoms into well-defined supramolecular structures. Understanding this process is key for preparation of structures with atomic precision. This thesis studies the supramolecular structure of tetrakyanochinodimetan molecules (TCNQ) and iron atoms on graphene grown on iridium crystal with the (111) surface. The surface analysis was performed by scanning tunneling microscopy, low-energy electron microscopy and x-ray photoelectron spectroscopy. The thesis introduces the growth process of a good quality graphene on Ir(111) and the synthesis of Fe-TCNQ networks 20 nm x 20 nm large and describes their structural properties. Three preferential orientations of Fe-TCNQ on graphene were identified. The networks will be used in follow-up studies targeting their magnetic properties.
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Design of pulse generator for laser spectroscopy
Cebo, Patrik ; Žalud, Luděk (referee) ; Kaiser, Jozef (advisor)
This diploma thesis deals with the design of a precise multi-channel pulse generator for the synchronization of laser-induced breakdown spectroscopy (LIBS) instrumentation. The thesis reflects current state-of-the-art solutions in communication and trends in the field of laser spectroscopy. Moreover, the device is based on the modern implementation of embedded devices using C and C++ programming languages using the Ethernet for communication. The communication with the control software is provided via the SDD protocol; designed at CEITEC BUT. Finally, the data of the SDD protocol are sent by the hypertext transfer protocol (HTTP) protocol in native file format (JSON). This thesis brings the synchronization of the 10 devices by precision timing.
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Development of UHV STM/AFM
Pavelec, Jiří ; Neuman, Jan (referee) ; Kalousek, Radek (advisor)
The main focus of the thesis is on the actuator, which is used for nanopositioning of laser beam in-site AFM (Atomic Force Microscopy). The appropriate shape of supply pulse and frequencies were searched and optimized. They make slip-stick motion of the piezo actuator. Possibilities of solving troubles with UHV (Ultra High Vacuum) are described on the basis of experiment and simulation.
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Materials and their application in low temperature parts of STM microscope
Voňka, Jakub ; Vlček, Ivan (referee) ; Urban,, Pavel (advisor)
Průtokvý kryostat s kapalným héliem (LHe) je vyvíjen skupinou Kryogeniky a Supravodivosti na Ústavu Přístrojové Techniky pro stávající rastrovací tunelovací mikroskop (STM) pracující za pokojové teploty na Ústavu Fyzikálního Inženýrství. Tato bakalářská práce se zabýva výběrem materiálů a určením jejich vlastností pro potenciální využití v některých částech nízkoteplotního STM mikroskopu (LT-STM), se zaměřením zejména na tepelnou vodivost v teplotním rozsahu od 4 K do 300 K. Je zde probírána problematika měděných svazků pro tepelné spojení vzorku s tepelným výměníkem. Slitina CuCrZr byla podrobně zkoumána jako vhodný materiál pro držák vzorku. Byly určeny tepelné toky málo vodivými podpěrami založenými na styku sférických ploch pro použití jako izolace mezi studeným držákem vzorku a STM stolkem.
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