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Interaktivní tabule ve výuce anorganické chemie na SŠ - IV.A (14. skupina) / Interactive Whiteboard in Inorganic Chemistry Teaching - Group 14 of the Periodic Table of Elements Secondary EducationStudničková, Zuzana January 2013 (has links)
1 Abstract The subject of this thesis was creating of teaching material for an interactive whiteboard using the SMART Notebook program. The material was created in form of interactive presentations designed to be used in chemistry lessons at secondary schools. The unifying theme of presentations was the 14th group of the periodic table of elements. The thesis also includes a description of the way the presentations were made and instructions for teachers how to work with them. It also introduces some advantages and disadvantages of working with the SMART Notebook software. Key words: Interactive whiteboard, SMART Notebook, group 14 of the periodic table of elements, presentations, carbon, silicon, tin, lead, germanium
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Záporná elektroda lithných sekundárních článků / Negative Electrode of Lithium Secondary CellsMakovička, Jaromír January 2008 (has links)
The thesis deals with a study of the various carbon materials for negative electrode of lithium ion accumulators. The object of the work is to gain the most knowledge about these materials and to project their possible improvements. In the first part of the work is described the latest knowledge about carbon materials and their application. In the following parts of the work is handled about manufacture,optimization of composition of electrode and the choice of carbon material for liquid and gel electrolyte.
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Využití elektrod na bázi uhlíku pro elektrochemickou detekci v průtokových metodách / Application of carbon based electrodes for electrochemical detection in flow systemMika, Jan January 2012 (has links)
Carbon is due to its electrochemical properties a favourite material for construction of electrodes suitable for detection in flow system. The two most often used techniques (coulometric and amperometric) will be discussed in this Thesis. Carbon paste electrodes (CPE) represent the amperometric detectors. CPE are unstable in the medium with high content of organic solvents, which might complicate their application in HPLC, where the mobile phase contains organic component. It is interesting, that glassy carbon paste electrodes are more stable under such conditions. The change of surface and response of the electrode caused by the effect of methanol are described in this Thesis along with the possible reason of stability of GCPE. Roughing of the surface exposed to methanol is demonstrated by confocal microscopy. This effect leads to increase of height of the peak, background current and noise and to the shift of peak potential to less positive values. These changes are dependent on the time of exposure and the concentration of methanol. Coulometric detectors work with high conversion effectiveness and sensitivity, but in case of their passivation, reactivation is a relatively complicated problem, often leading to the replacement of electrode material. Answer to this problem can be given by using...
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Palatabilita druhů, jejich bionomické vlastnosti a rychlost rozkladu detritu / Species palatability, life history traits and litter decomposition ratePÁLKOVÁ, Kateřina January 2007 (has links)
Palatability of 20 meadow plant species was assessed in the slug grazing experiment conducted. Monocots exhibited significantly lower palatability than dicots. Litter decomposition rate was assessed in the field litter-bag test. Linear regression analysis was performed to answer the main question whether species palatability is related to litter decomposition rate and whether it is determined by the carbon or nitrogen content. Phylogenetically independent contrasts were used to eliminate correlated phylogeny effect. Regression trees were used to detect the effect of species traits on species palatability and litter decomposition rate.
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Záporná elektroda olověného akumulátoru pro hybridní elektrická vozidla / Negative lead-acid battery electrode for hybrid electric vehiclesDvořáček, Daniel January 2020 (has links)
The thesis briefly discusses the issue of electrochemical power sources, especially with a focus on lead-acid batteries operating in modes that are typical of hybrid electric vehicles. The theoretical part of the thesis should be a good basis for the subsequent practical part, in which several experimental electrodes and their parameters will be performed and evaluated. The output of the practical part will be conclusions regarding the influence of different variants of modified carbon used as an additive in the active material of the negative electrode on the capacity and life of cells
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Numerické metody zpracování obrazů z kosmické sondy NASA SDO / Numerical methods of image processing from NASA's SDO space probeMeduňa, Tomáš January 2020 (has links)
Tato práce se zabývá zpracováním snímků Slunce pořízených kosmickou sondou SDO na různých vlnových délkách a vizualizací výskytu třikrát ionizovaného uhlíku C IV jejich vhodným složením. V práci jsou uvedeny základní informace o Slunci a jeho atmosféře, dále je shrnuta potřebná teorie a možné postupy vizualizace, které jsou následně vyhodnoceny a porovnány. Součástí je i vytvořený program pro snadnou tvorbu snímků vizualizujících uhlík C IV.
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Porovnání separační účinnosti v jednotlivých stupních technologické linky úpravy pitné vody / The comparison of separating efficiency in the individual degrees of technological line in drinking water treatmentŠípková, Helena January 2015 (has links)
This thesis is focused on technological processes during drinking water treatment. The emphasis is put on monitoring indicators of organic substances present in water and indicators of the biological stability of treated water. The experimental part is focused on the comparison of separation efficiency of drinking water treatment technological processes by monitoring of chemical oxygen demand, absorbance measured at 254 nm, bioseston, culturable microorganisms and assimilable organic carbon.
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Vlastnosti uhlíkových materiálů pro elektrody superkondenzátorů / Properties of carbon materials for supercapacitorsŠtorek, Ondřej January 2009 (has links)
The Master’s Thesis deals with supercapacitators based on principle of eletrical double layer. At the outset there is an explanation of supercapacitor working principal. We discussed advantages and disavantages supercapacitators compared with other related elements in electrotechnics. Materials based on carbon and their structure for production supercapacitators are described too. In next part of Thesis we mention different methods and techniques for the measurement and the evaluation of supercapacitators‘s capacities. Optimal materials for production supercapacitators are presented in conclusion.
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Záporné elektrodové materiály v lithium-iontovém akumulátoru / Compatibility of negative electrode materials at system of lithium-ion batteryŠikuda, Milan January 2015 (has links)
This thesis deals with a study of lithium-ion batteries. It is focused into negative electrode materials and electrolytes. In this thesis is presented synthesis, electrochemical properties, possibilities to improving negative electrode materials as LTO (Lithium Titanate Oxid) and graphite. These electrode materials were investigated with respect to their compatibility at electrolytes with carbonate solvents, Sulfolane and DMF (DiMethylFormamide) in detail. The main aim of this thesis is to characterize electrode materials and electrolyte properties depending on wide range of temperatures and their comparison for the purpose of achievement of the best solution. The thesis is divided into two main parts. The theoretical part of thesis describes composition, process of synthesis and analysis of lithium-ion cell. Practical part contains measuring and evaluating of charge-discharge and irreversible capacity characteristics related to variety of environmental temperatures.
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Příprava a charekterizace porézních dvojvrstev ceroxid/uhlík na křemíkových substrátech / Preparation and Characterization of Porous Cerium Oxide/Carbon Bilayers on Silion SubstratesDubau, Martin January 2016 (has links)
This doctoral thesis concerns the preparation of porous cerium oxide/carbon bilayers on silicon substrates. In this regard, carbonaceous films in the form of amorphous carbon (a-C) and nitrogenated amorphous carbon (CNx) are considered. The influence of various process parameters of the cerium oxide deposition on the morphology of the final cerium oxide/carbon bilayer is investigated. A correlation could be found between the morphol- ogy of the bilayer and the stoichiometry of the cerium oxide film determined by means of XPS. Furthermore, a study regarding the chemical composition of the used carbonaceous films by means of various spectroscopic techniques is presented. It was found that the chemical composition of the carbonaceous films strongly depends on the deposition con- ditions of these films and influences the behaviour of these films during oxygen plasma treatment and cerium oxide deposition, respectively. 1
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