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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.
41

Hodnocení aktuálního stavu krajiny Mostecka / The evaluation of actual conditions of Mostecko region

RADOŠOVÁ, Tereza January 2012 (has links)
The work is engageded in comparison of flora in both recultivated and areas under succesion in Most coal basin. The mapped areas are situated not far from the towns Most and Duchcov. The coalmining and following recultivation have been handed down there for many years. The first reference to coalmining in Most region comes back to 1613. All kinds of these days mining devastate the landscape, that?s why the restoration of it must be done. The aim of the work is to find out and evaluate the latest vegetation composition in he selected areas, to classify territories according to Catalogue of biotopes, and to carry out the contemporary conditions of landscape character in Most region.
42

Velikostně rozlišený atmosférický aerosol v pracovním prostředí povrchového hnědouhelného dolu / Size segregated atmospheric aerosol in selected workspaces of coal strip mine

Basslerová, Barbora January 2017 (has links)
The workers are exposed to aerosol particles in a coal strip mine. These particles are usually generated by the Bucket-wheel excavators which break the mined rock. The goal of the thesis thesis was to compare the concentrations of atmospheric aerosol particles - PM on the Bucket-wheel excavator Schrs 1320, the Stacker ZPDH 6300 and the Bucket- wheel excavator K 800/N2 in the coal quarry Doly Nástup Tušimice, and then to answer the questions what is the main cause of increased concentration PMx and whether the mining machines are different from each other. The measurement was realized stepwise on every mining machine in the time period from 12. 8. to 2. 9. 2016. The concentrations of PM1, PM2,5 and PM10 were measured by two portable laser nephelometers in the cab drivers and the outdoor walkway of the mining machines with the integration time of 1 minute. The air temperature and the relative humidity were monitored in both types of settings in every five minutes. The PMx concentrations variability is usually determined by the type of work and by the type of smoking. Consequently, PM concentrations on the mining machines were compared at the morning exchanges and evening exchanges, during the outdoor cleaning by sweeping, the indoor cleaning by hoovering and during the smoking. The highest...
43

Změny v časování klíčení způsobené interakcemi se sousedními semeny vzhledem k vlastnostem druhů. / Changes in timing of germination caused by neighbouring seeds and how it is connected with species traits.

Kos, Pavel January 2017 (has links)
The time when the seed germinates is very important. Ability to change the time of germination may be very advantageous. It allows the emerging seed to choose the best time according to abiotic conditions, and also to avoid of competition with neighbouring individuals. The seed reacts not only on adult plants and seedlings, but also on other seeds, with which is able to communicate. For a better understanding to this mechanism I conducted an experimental study with twenty-six species. The species were selected according to their position in long succession seres of mesic/xeric abandoned fields in Český kras. The seeds were left to germinate in pairs in all combinations among them. Here I present the results where I show how the time of emergence changes, depending on presence of neighbouring seed. Also, I show how these changes in germination are related to species specific traits. Out of this, I tried to influence communication between seeds by adding activated carbon. Activated carbon should stop the communication by highly absorbing surface. The time of germination of seeds which germinated alone was not proportional to the time of germination of seeds which germinated with neighbours. This correlation showed up like nonlinear, late-emerging seeds emerging unproportionally later when emerging...
44

Vliv těžby hnědého uhlí a rekultivací na socioekonomický rozvoj okresu Sokolov / The brown coal exploitation a recultivation impact on socioeconomic development of District Sokolov

Jašová, Lucie January 2008 (has links)
This diploma thesis deals with revitalization of landscape and recultivation in Sokolov region. In its first part the paper deals with socioeconomic analysis of region Sokolov. The main task of this analysis is, evaluate present progress of this region. It also describes history of brown coal mining in brown coal field of Sokolov region and negative effect for landscape. Next chapters of this thesis show: recultivation in general, project documentation, financing arrangements, company Sokolovská uhelná a.s. and its privatisation. One of the most important parts of this diploma thesis deals with recultivation in Sokolov region and description of particular locations in this region. The last part gives an evaluation of socioeconomic developmet in dependence on recultivation in Sokolov region.
45

Energetické otázky v zemích Visegradské čtyřky / Energetics in Visegrad Group

Horák, Lukáš January 2010 (has links)
Main purpose of this thesis is to find out how self sufficient concerning the energy raw materials are countries within Visegrad group. Further purpose of my thesis is to analyse total primary energy supply, the structure of energy supply in countries of Visegrad group and its developments in last 4 decades. Furher I want to reveal how the structure of total primary energy supply and structure of electricity generation reflect the disponibility of raw materials in these countries and transformation of economics in the nineties. A sub-objective of my work will examine how countries of the Visegrad Four use the potential of renewable energy sources and how they support it.
46

Sledování účinnosti odstraňování pesticidů ze zdrojů pitné vody vybranými adsorbenty / Monitoring the effectiveness of removing pesticides from drinking water sources by selected adsorbents

Gottwald, Martin January 2019 (has links)
In the introductory part of this diploma thesis the pesticidal substances and their legislative requirements in drinking water are described. This is followed by a description of technologies in which pesticides can be removed and used in water treatment plants. In the practical part of the thesis is described description of the experimental procedure of the removal of pesticides on two selected adsorption materials (Filtrasorb F100 and Bayoxide E33) and subsequently this experiment is evaluated.
47

Sledování účinnosti odstraňování léčiva z vody vybranými adsorbenty / Monitoring drug removal efficiency from water by selected adsorbents

Moravčíková, Světlana January 2020 (has links)
This diploma thesis deals with the efficiency of removal of pharmaceuticals from drinking water by selected adsorption materials. The first part describes sources of pharmaceuticals in drinking water and possible ways of contaminating water by pharmaceuticals. Subsequently, the pharmaceuticals most commonly found in the environment - nonsteroidal anti-inflammatory drugs, antibiotics, psychiatric drugs and sex hormones - are described in more detail. Next, the thesis describes the processes used for removal of pharmaceuticals. These are activated carbon adsorption, membrane processes and advanced oxidation processes. The last chapter of the theoretical part of the thesis deals with water treatment plants, where the technologies for removing drugs are already in operation. In the practical part of this thesis an experiment was performed and evaluated, for a purpose of comparing the efficiency of selected sorption materials in the removal of diclofenac from water. Filtrasorb F100, Bayoxide E33 and GEH were used.
48

Využití biouhlí jako sorpčního materiálu pro odstranění syntetických vonných látek z vod / The use of biochar as a sorption material for the removal of synthetic fragrances from water

Kašparová, Jarmila January 2020 (has links)
Synthetic fragrances (musk) are artificially produced organic compounds. It is used as fragrance ingredient in personal care products. Substances from this group have the ability to withstand the cleaning process in wastewater treatment plants. The physico-chemical properties of musk compounds cause their accumulation in the living and non-living components of the ecosystem, where they behave as persistent pollutants. The adsorption process is considered to be one of the most widely used separation and purification processes. The adsorption processes of a solution of sixteen synthetic fragrances took place with biochar and activated carbon. Solid phase microextraction (SPME) was used as a method for extracting analytes. Gas chromatography coupled with mass spectrometry (GC-MS) was applied for final analysis, time of flight analyzer was used as detector. The data were fitted with adsorption isotherms.
49

Využití fluorimetrie pro detekci stopovačů proudění podzemních vod / Utilization of fluorimetry for detection of underground water tracers

Pokora, Zdeněk January 2008 (has links)
The thesis studies detection of fluorescein for coloration experiments in surface and underground water. The first part of the work deals with the adsorption of fluorescein on active charcoal from water and desorption by means of different desorption solutions. The results of measurements are used for practice of coloration experiments in karst research. In the second part of thesis it is researched the option of automated record of fluorescence concentration and its detection by means of laser induced fluorescence with confocal microscope.
50

Kotel na spalování dřeva s hnědým uhlí (váhový poměr 50/50),30t/h / Steam boiler for burnig mix of wood and sub-bituminous coal(mixing 50/50).35t/h

Chmelíček, Jiří January 2013 (has links)
This master´s thesis deals with the constructional and calculation design of the boiler for burning wood and sub-bituminous coal. The work is divided into several parts. First, stoichiometrics calculation and enthalpy calculations of air and flue gas are performed. It is calculated heat balance of the boiler, the boiler losses and the thermal efficiency of the boiler is determined. After designing the combustion chamber thermal calculation is made. Then, the dimensions and individual heating surfaces are proposed. At the end of the calculations are controlling the overall energy balance.

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