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High frequency electron spin resonance spectroscopy
Hrubý, Jakub ; Perfetti, Mauro (referee) ; ShangDa, Jiang (referee) ; Neugebauer, Petr (advisor)
Elektronová spinová rezonance (ESR) je neinvazivní spektroskopická technika založená na magnetické rezonanci. Používá se v mnoha vědních oborech jako biologie, chemie a fyzika pro zkoumání systémů s nepárovými elektrony. Tato dizertační práce se věnuje spektroskopii vysokofrekvenční rezonance spinů elektronů (HF-ESR) a jejímu použití na paramagnetické koordinační sloučeniny. V první části je představen teoretický základ s rešerší literatury v této oblasti a jsou představeny aplikace HF-ESR. Dále jsou představeny metody použité ke studování těchto systémů. Zde jsou popsány doplňující metody (XPS, RS, UV-VIS, AFM, SEM) pro zkoumání vzorků a je představen návrh nové sublimační komory vysokého vakua, která byla sestavena pro tvorbu tenkých vrstech koordinačních sloučenin na površích. Následují výsledky dosažené pomocí HF-ESR na molekulárních kvantových bitech [Cu(dbm)2], jednomolekulárních magnetech [CoX2(dppf)], [Co(4MeO-L)2Cl2] a je nastíněna vize bolometrů na bázi grafenu pro detekci této třídy sloučenin. Výsledky jsou diskutovány a jejich implikace jsou shrnuty v závěru. Reference a autorské výstupy pak uzavírají celou tuto práci.
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Deposition of Molecular Magnets on „2D“ Materials
Vavrečková, Šárka ; Musálek, Tomáš (referee) ; Hrubý, Jakub (advisor)
This thesis deals with deposition of single-molecule magnets on 2D materials and studies their behavior on surfaces. Theoretical part contains information about properties of single-molecule magnets, deposition methods and also information about chosen 2D materials – graphene and molybdenum disulfide. Further, the physical principles of the selected characterization methods (atomic force microscopy, Raman spectroscopy, X-ray photoelectron spectroscopy and electron paramagnetic resonance) are described. In the experimental part graphene and molybdenum disulfide were exfoliated. Afterwards, depositions of single-molecule magnets from solution and by thermal sublimation were made. After that, samples were analyzed using the mentioned methods and results were discussed.
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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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Low temperature heating system
Hrubý, Jakub ; Košner, Jan (referee) ; Hejčík, Jiří (advisor)
The aim of this thesis is to design a low temperature heating system which will be operating in multifunctional wooden house. Ground souce heat pump being the pruducer of the energy in this systém, while the underfloor heating.being the consumer. After a short brief on theoretical level of used systems and devices, there comes a practical part of equations, designing and finding of a best solutions for all necessary parts of heating system. All imporant generated data are packed in a lucid charts. Thesis is trying to be somewhat brief but factical, and just a little bit stylish. At the end of the work there are some economical conclusions of used system like annual energy consumption cost, payback periods comparisons to other systems etc.
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Preparation and Characterization of Graphene Based Hybrid Materials
Hrubý, Jakub ; Novák, Jiří (referee) ; Neugebauer, Petr (advisor)
Grafen v kombinaci s komplexy kovů by mohl poskytnout nové přísutpy v hybridních materiálech založených na grafenové bázi a v oblasti molekulárního magnetismu. Obě témata jsou velmi diskutovaná jako taková, nicméně, výzkumu vedoucího k možnosti jejich míchání není mnoho. Vzorky byly připraveny sonikací grafitu v kapalné fázi, což vedlo k exfoliaci grafenu. Následně byly nadeponovány pomocí modiikované Lagmuirovy– Schaeferovy depoziční metody různé komplexy kovů na substrát pokrytý grafenem. Klíčovým krokem bylo určení vlastností takto připraveného materiálu. Proto byly následně vlastnosti takového hybridního materiálu charakterizovány pomocí vysokofrekvenční elektronové paramagnetické rezonance (angl. HFEPR), rastrovacího elektronového mikroskopu, (angl. SEM), Ramanovou spektroskopií a čtyř bodovou metodou měření odporu. V této práci jsme potvrdili naši presumpci, že je možné vytvořit hybridní materiál smícháním exfoliovaného grafenu s molekulárními magnety pro získání nových magnetických a elektronických vlastností, které by mohly být využity v další generaci detektorů a elektroniky.
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Preparation and application of metal and semiconductor nanostructures
Hrubý, Jakub ; Kolíbal, Miroslav (referee) ; Šimšíková, Michaela (advisor)
Tato práce se zabývá teoretickými základy přípravy, charakterizace a možnými aplikací nanostruktur. V experimentální části je nastíněna syntéza a charakterizace nanostruktur. Ušlechtilé kovy jsou zastoupeny zlatem a stříbrem. Oxid zinečnatý jakožto II--VI polovodič a kompozit oxidu zinečnatého a oxidu měďnatého byly také syntetizovány bottom-up metodou. Připravené částice tvořily různé tvary, jako například kuličky, tyčinky, dlaždičky a takzvané nanokytičky. Částice byly posléze charakterizovány. Optickou mikroskopií byl proveden přibližný odhad morfologie. Skenovací elektronový mikroskop byl použit pro detailní pohled do struktury vzorku. Další charakterizační metody jako fotoluminiscence a absorbance byly využity u CuO/ZnO kompozitu.
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Ideal cycle turbocharged internal combustion engines
Hrubý, Jakub ; Jedelský, Jan (referee) ; Štětina, Josef (advisor)
The aim of this thesis is description of various charging methods as a one of the most attainable form of ramping up the power and fuel consumption efficiency of naturally aspirated engines nowadays. Main aspect is thermodynamic part of the whole problem, especially the comparison of thermal efficiencies between different cycles. After a short history brief, main reasons why is charging so important are answered. General description, work principles, advantages and disadvantages of new technologies are also included. Emphasis is aimed at topicality and graphic interpretation. Thesis is dealing with charging diesel engines, but also petrol engines in automotive industry and offering a possible way of future development.
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Study of Behaviour of Paramagnetic Molecules on Surfaces
Bouček, Martin ; Procházka, Pavel (referee) ; Hrubý, Jakub (advisor)
This thesis deals with behaviour of paramagnetic molecules of copper(II) pthalocyanine (CuPc), hemin and bis(dibenzoylmethane)copper(II) ([Cu(dbm)2]) on surfaces of glass and polycrystalline gold. Additionally the [Cu(dbm)2] is studied on graphene surface. Molecules are deposited on substrates via wet chemistry methods. They are studied after deposition with atomic force microscopy (AFM), electron paramagnetic resonance (EPR), scanning electron microskopy (SEM) and X-ray photoemission spectroscopy (XPS).
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The usability of secondary raw materials in the design of liquefied suspensions based on soil
Hrubý, Jakub ; Kulísek, Karel (referee) ; Černý, Vít (advisor)
The bachelor's thesis deals with the usability of secondary raw materials in the design of liquefied suspensions based on soils in the form of self-compacting grouts. The soil treated in this way can be used as a substitute for backfill material for excavations of engineering networks. The theoretical part deals with the classification and description of soils. Furthermore, the types of soil stabilization using lime, cement, including their liquefaction, are mentioned. A wide range of potentially suitable secondary raw materials and liquefaction mechanization is presented. In the practical part, the basic soil F6-Cl is selected on the basis of a set of available soils. The basic reference mixture consists of soil, lime, cement and liquefier. A proposal for the concept of experimental verification is presented. Part of the concept is the automated calculation of input raw materials. The effect of the action of the superabsorbent polymer and the accelerating additive is verified. Based on optimization selections, functional secondary raw materials are selected. The basic recipe with the optimal amount of accelerating ingredient achieves the best results. Recycled concrete and brick generally improve the resulting parameters. Bed ash achieves the highest strength with the lowest shrinkage.
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The Kingdom of Sumpa in the Light of Tibetan Sources.
Aguas Maisels, Bruno ; Berounský, Daniel (advisor) ; Hrubý, Jakub (referee)
This thesis is concerned with the term Sumpa in all its connotations, as a name of the tribe, clan name, and name of the area inhabited by them. Sumpa is portrayed as a confederation of nomadic tribes that inhabited the areas in present-day northeastern Tibet from early historical times to the seventh century when their territory was annexed by the rising Tibetan Empire and they were assimilated. The thesis is divided into two parts. The first part aims to present a brief overview of the history of these people, their origin, defeat, and assimilation, as well as the possible extent of their territory and traces they left in the area. In the second part, the English translation of the relevant section from a Tibetan work named The Great History of Domé, Domé logyü chenmo (mDo smad lo rgyus chen mo), along with its transcription in the appendix, will be presented.
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