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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
241

Vliv intenzity dopravy a meteorologických podmínek na znečištění ovzduší / Influence of traffic volume and meteorological conditions on the air pollution

Vojtěchová, Ivana January 2009 (has links)
Transport, whose intensity year by year increase, has assuredly influence on air quality. This issue solution will be focused especially on localities burden with transport in urban areas. The contribution of transport to increased values of air pollution will be evaluated with regards to meteorological conditions. Background stations from Czech Hydrometeorological Institute categorization will be chosen such as comparative sites. Pollutants emitted from traffic such as particulate matter, nitrogen oxides and carbon monoxide will be observed except meteorological conditions.
242

Sol-gel proces s reverzními micelami / Sol-gel process using reverse micelles

Lukešová, Magdalena January 2011 (has links)
Práce popisuje přípravu tenkých transparentních vrstev oxidu titaničitého metodou sol-gel procesu s reverzními micelami, které jsou jedinečným uskupením zajišťujícím uniformní velikost připravených částic. Neionogenní tenzid byl použit jako templát. Pomocí materiálového tisku, tedy specializovanou formou inkoustového tisku, byly připraveny tenké filmy oxidu titaničitého nanesením 1–4 vrstev. Po kalcinaci byly připravené vrstvy oxidu titaničitého charakterizované šířkou zakázaného pásu. Struktura vrstev byla popsána optickou mikroskopií a SEM. Fotokatalytická aktivita byla ověřena oxidační reakcí 2,6-dichlorindofenolu a rozkladem kyseliny stearové, která byla přímo natištěna na vrstvy oxidu titaničitého. Fotoindukovaná změna hydrofility byla studována pomocí měření kontaktního úhlu smáčení vody. Fotokatalytická účinnost připravených filmů rostla s počtem vrstev oxidu titaničitého.
243

Měření vlastností oxidů manganu (MnOx) metodou EQCM / Study of manganeese oxides properties by the EQCM method

Pléha, David January 2010 (has links)
The present work deals with the use of manganese oxide as a catalyst for positive electrode of fuel cells. The theoretical part is to analyze the problem of fuel cells, focusing on lowtemperature fuel cells. Are discussed and the methods of measurement and evaluation of properties of manganese oxide layer. The practical part deals with doping electrolytic manganese dioxide salts of divalent metals and monitoring their behavior in the cyclic voltammetry by the EQCM method.
244

Využití oxidu yttria pro vytváření antireflexních vrstev solárních článků / Yttrium oxide layers for antireflection coating of silicon solar cells

Dostál, Vladimír January 2010 (has links)
This work deals with deposition of yttrium oxide layers on silicon substrate (P – type) by using magnetron and reactive magnetron sputtering. Experiments which were made are further described. After that, work is focused on evaluation of deposited layers by using FTIR measurement technique and spectrophotometry. At the end of the work results of experiments are discussed also with the future progress.
245

Sledování elektrických vlastností nanokompozitních materiálů / Study of electrical properties of nanocomposites

Ovsík, Jiří January 2012 (has links)
The present work deals with the electrical properties of nanocomposite materials. Samples for the experiment are made of epoxy resin as a matrix and oxides TiO2, Al2O3, WO3, SiO2 as nanofillers in 0.5 and 1 percent performance. The experimental samples are measured in temperature and frequency dependence of relative permittivity, dissipation factor, rezistivity and are broken down by the influence of filler on the electrical properties of the polymer. Attention is also paid to the mechanical properties of nanocomposites.
246

Zkoumání vlivu oxidu titaničitého na životnost olověných akumulátorů s aplikovaným přítlakem / Influence of titanium dioxide on the life of lead acid batteries with applied pressure

Řihák, Pavel January 2013 (has links)
Hybrid electric vehicles use lead acid batteries operating under partial charge. Battery life of these batteries is dependent on the speed of development of lead sulphate (PbSO4) to the negative electrodes. Different admixtures are affected battery life. This work deals with the influence of titanium dioxide on the negative active material in lead battery. Mainly devoted to the influence of the applied pressure.
247

Polovodičové senzory plynů na bázi oxidu ciničitého / Tin dioxide based semiconducting gas sensors

Gablech, Imrich January 2014 (has links)
This project is aimed at semiconductive gas sensors based on tin dioxide. In the first part, gas sensors are divided depending on their principal of functionality. Next part is about functionality of tin dioxide gas sensors and the possibilities of active layer modification. Experimental describes gas sensor from its drawing until construction, testing and characterization. Several microelectronic technologies such as thin-film, thick-film, LTCC, spray-coating or wire-bonding were used for constructing the sensor. In the last part properties of gas sensors and differences in functionality between modified and unmodified gas sensor are summarized.
248

Možnosti zvýšení užitných vlastností lehčeného cihlářského střepu / Possibilities of light weight brick body innovation

Fric, Jan January 2013 (has links)
This diploma thesis will discuss possibilities of using nanofibres to increase the strenght of the brick body, replacement of the current schrinkage reducing agent – quartz sand by stone dust, the use of flocculants as pore-forming agent and coloration of the body using iron trioxide.
249

Metody snižování emisí oxidu uhličitého / Methods of carbon dioxide emission reduction

Mališ, Jan January 2009 (has links)
Master's Thesis is focused on production of CO2 from fossil fuels combustion and the methods of CO2 emission from fossil fuels combustion reduction, resp. pre-combustion and post-combustion separation of CO2. Recapitulation of world consumption of primary energetic resources and carbon dioxide production as a result of theirs combustion in years 1971 - 2006 was made using a number of information sources. Whilst combustion o fossil fuel is related with production of CO2, calculation of emission rate of CO2 from fossil fuels (natural gas, crude oil and coal) was demonstrated. The Case Study of energy and material balances of gas turbine cycle with synthesis of methane from CO2 and from hydrogen which is produced in water splitting was made, using CHEMCAD software.
250

Moderní metody mokrého čištění spalin / Modern methods of wet cleaning flue-gas

Kubíček, Jan January 2010 (has links)
The main theme of this master’s thesis is to acquaint with flue gas cleaning problems. Also modernization of experimental device called “O-element”, installed in laboratory at Institute of process and environmental engineering, is involved in this master’s thesis. “Oelement is used for cleaning acid elements from flue gas. Further there are results of experimental measuring on this device, and their estimation.

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