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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.
181

Kvalita vody a vodácká turistika na vybraných západočeských řekách / Quality of water and water touring on selected West Bohemia rivers

Šimice, David January 2010 (has links)
3 Abstract Title: Quality of water and water touring on selected West Bohemia rivers Aim: The main aim of the thesis was to find out if there are changes of water quality in the most significant West Bohemia rivers as a result of the changing approach to our environment in the past several years. Furthermore, to consider whether the water quality has changed in relation to finished water management projects and whether this change influenced using rivers for water touring. The observed rivers: Úhlava, Úslava, Radbuza, Mže, Berounka and Střela. Methods: The first part of the thesis, discussing the water quality, analyzes available data collected from written and electronic resources and discussions with experts. The gained material mostly within the last 10 years was organized, compared and summarized. The second part brings the evaluation by canoeists who regularly canoe down these rivers and can visually judge the water quality. This information was interpreted from semi- structured interviews with canoeists. Results: Our presumption that the water quality on the selected West Bohemia rivers is improving was proved, which is one of basic conditions for water touring as well. Keywords: West Bohemia rivers, water touring, water quality, pollution
182

Analýza časových řad koncentrací aniontů a kationtů na povodí Kopaninského toku ve vazbě na využití půdy. / Analysis of time series of anions and cations concentrations in the Kopaninsky stream catchment in relation to land use.

KOUŘIMSKÁ, Kateřina January 2008 (has links)
Water quality of small streams in agricultural landscape is mostly classified as polluted or very polluted. The reason of enhanced mineralization of organic mass in soil can be found in changed physical, chemical and biochemical properties of soil profile, which negatively display in mineralization of organic mass and nitrogen release to soil water. Analysis of water quality in agricultural river-basin prove that quality of surface water in areas with high nitrate loadings did not significantly improve in recent years. Nitrates in water are a distinct anthropogenic factor, which defines well disturbance in natural environment. This thesis deals with analysis of time series of nitrate concentrations in the Kopaninsky stream catchment in Bohemo-Moravian Highland. Further the progress in nitrate concentration and its seasonal component is researched.
183

Cesta vody - land artové prvky v kontextu urbanizace české krajiny na Českokrumlovsku / The path of the water - Land art elements in the context of urbanization of Czech countryside of Český Krumlov

NOWAK, Bohumír January 2010 (has links)
This work is complementary theoretical part of my practical art project on "Path of Water". Introductory chapter is devoted to the water. I'm investigating physical properties of the water in different states of matter and particularly its movement. I even consider its place in the art. The second chapter is devoted to the development of the landscape and its changes caused by the nature and human. The third chapter deals with the meaning, origin and history of land art in the world and in Bohemia. The fourth chapter describes the most interesting places and history surrounding the village Staré Dobrkovice in which the chosen place can be found. Intentions and descriptions of implementations are dealt with in fifth chapter. In the end I summarize the development of entire project and individual parts and I evaluate individual achievements and meeting of determined criteria.
184

Porovnání jakosti vody na zemědělsky využívaném povodí v letech 1983 - 1985 a současným stavem. / Comparison of water quality on agricultural catchment in 1983 - 1985 and in present.

POKORNÁ, Zuzana January 2009 (has links)
There are remarkable changes in water quality at the Jenínský stream catchment that lies in the Šumava foothills which were caused by change in land use. Two subcatchments, called J1 and J2, were monitored. In the first period 1983-1985, the two subcatchments were agriculturaly used, the land was fertilized and ploughed and cereals and corn were grown. In the second period 2004-2008, there were grasslands and the land was extensively used as pasture. This change in land use caused evident changes in water quality at the Jenínský stream catchment. The decrease of all monitored indices was remarkably seen in the concentrations of nitrate and ammonium. The average nitrate concentration in 1983-1985 was 39,5 mg . l-1, and decreased by 43,3% to the value of 16,9 mg . l-1 in 2004-2008. The greatest decrease of 85,9% was found in average ammonium concentration (0,4 mg . l-1 dropped to 0,05 mg . l-1). The positive effect of the change from arable land to grassland was confirmed and we can see it in the amount of nitrogen compounds and resulting improvement of water quality.
185

Datování vývěrů radioaktivních minerálních vod v krkonošsko-jizerském krystaliniku metodou 230Th/234U / Dating of radioactive mineral springs of the Krkonoše-Jizera crystalline by 230Th/234U method

Fanta, Martin January 2016 (has links)
The isotopes 238 U, 234 U and 230 Th, as members of the uranium-radium decay chain, are fractionated in the environment by changes of geochemical conditions, and they can be used for dating of recent or past geochemical processes in the Quaternary. Samples of water with uranium and of water-activated solids were taken of radioactive mineral water springs at two study sites in the area of Krkonoše-Jizera crystalline complex: Svatý Vojtěch (St. Adalbert) in Horní Malá Úpa, and Bukový Pramen in the Těsný důl valley in Janské Lázně. Uranium was co-precipitated in field conditions with hydroxides of FeIII+ in 50-liter water samples of the radioactive springs. In the lab, uranium and thorium were separated from water precipitates, as well as from solid samples after their chemical decomposition, using chromatographic extraction agent UTEVA. All the three isotopes of interest emit alpha particles, and so their activities were measured by alpha spectrometry and expressed as 234 U/238 U and 230 Th/234 U ratios. As an internal standard, 232 U/228 Th was used. The resulting 234 U/238 U activity ratios of four water samples measured ranged from 1.0747 to 1.423. In twelve samples of solid phases activity ratios 234 U/238 U from 0.861 to 1.129 were determined. The 230 Th/234 U activity ratios form two distinct...
186

Environmentální účinky radiofarmak obsahujících 223 Ra / Environmental Effects of 223-Ra Radiopharmaceuticals

Krmelová, Tereza January 2016 (has links)
Title: Environmental Effects of 223 Ra Radiopharmaceuticals Author: Tereza Krmelová Branch: Environmental chemistry Type of thesis: Diploma thesis Advisor: Doc. Ing. Stanislav Smrček, CSc Abstract: In thesis was studied the possibility of extracting the nanoparticles of titanium dioxide or hydroxyapatite with bounded 223 Ra by root system of tested plant species Avena sativa and Zea mays as a model for phytoremediation technologies. The thesis obtains data to assess the potential of residues radioactivity and nanomaterials entering the food chain. There was also verified an experiment of 223 Ra phytoextraction, in the form of nitrate, in effects on addition of EDTA, which was conducted in Bachelor thesis. This experiment was repeated because of its results, which were inconsistent with generally described phytoextraction efficiency improvements after adding the complexing agents. In this work was primary studied translocation of radioactive material from the root to shoot. Experimentally was confirmed the extraction of nanoparticles with bounded 223 Ra and translocation into shoot. In the case of Avena sativa, capturing of nanoparticles hydroxyapatite with bounded 223 Ra was 53 % of which 88 % of activity was recovered in roots and 12 % in shoots. Capturing nanoparticles of titanium dioxide with bounded 223...
187

Změna kvality vody v malých povodích po postavení čistírny odpadních vod / Water quality change in small watersheds after sewage water treatment plant building

Rödlová, Sylva January 2010 (has links)
Změny kvality vody v malých tocích, vyvolané vybudováním čistírny odpadních vod, představují doposud málo studované a přitom velmi aktuální téma současné hydrologie. Tato studie se zabývá popsáním těchto změn a faktorů, které je ovlivňují. Pro účely výzkumu bylo vybráno pět malých, zemědělsky využívaných povodí prvního řádu (čtyři povodí průměrně 6 km2 , jedno 16 km2 ). V každém zájmovém území byla vždy jedna vesnice od 640 do 2 500 obyvatel. Během 7 - 16 let trvajícího měsíčního monitoringu základních indikátorů kvality vody (O2, BSK5, CHSKCr, TOC, konduktivita, N-NH4, N-NO2, N-NO3, PC, P-PO4) byla zachycena stavba čistíren v obcích. Spolu s daty o účinnosti čistíren byly vyhodnoceny změny kvality vody v toku. Identifikované typy změn ukazují na problematické aspekty vývoje kvality vody v malých povodích. Kromě očekávaného rychlého a razantního snížení hodnot zátěže po výstavbě čistírny odpadních vod se vyskytují i odlišné projevy změn - pouze mírné snížení zátěže, stagnace, dokonce i zvýšení koncentrací sledovaných indikátorů. Mezi další typické změny patří navýšení hodnot 1-2 roky před uvedením čistírny do provozu a opožděná nitrifikace v toku způsobená nevhodným provozem čistírny. Mezi nejdůležitější faktory ovlivňující změny patří provoz čistírny, velikost průtoku recipientu, zemědělské...
188

Využití systému LISp-Miner při analýze faktorů ovlivňujících dominanci sinic ve fytoplanktonu / Utilization of System LISp-Miner in the Analysis of the Factors Influencing the Dominance of Cyanobacteria in Phytoplankton

Hlaváčová, Tereza January 2013 (has links)
The aim of this work is to describe steps associated with solving analytical questions using the LISp-Miner in the data from water-analyzes of 12 ponds in South Bohemia in the period from year 2007 to 2012. Analytical questions are primarily focused on issues of cyanobacteria, based on instructions of data-owner, Povodí Vltavy, státní podnik. Apart from a description of the application of procedures KL-Miner, CF-Miner and 4ft-Miner on data, the work aims to prepare an automating process based on steps made during using procedures. The theoretical part is a summary of the basic concepts and principles associated with association rules and GUHA method. The practical part follows the CRISP-DM methodology. The result is a proposal of automation process by which it is possible to look for interesting rules in the hydrobiological and hydrochemical data. Then there is a set of recommendations for better utilization of database for KDD, with proposals how to modify and prepare the data.
189

Studie rekonstrukce úpravny vody / Reconstruction of Water Treatment Plant

Skříček, Jan January 2018 (has links)
The aim of the master thesis was to propose the reconstruction of the water treatment plant. I chose the water treatment plant in Čebín, which I have already describe with in the bachelor thesis. The water treatment plant has problems with increased iron, manganese and ammonium salts. In the first part I devoted myself to the current condition of the water treatment plant and the possibilities of removing the elements from the water. In the next chapter I compiled the equipment of the technological line. To remove iron and manganese, I suggested aeration using an injector, and for the removal of ammonium salts, potassium permanganate is used, which is used to regenerate the filters. A pair of pressure filters helps remove iron and manganese. In the last part of the thesis I described and evaluated the original condition of the water treatment plant. To evaluate the technical condition, I used the TEA Water web application.
190

Teplonosné látky tepelných soustav / Of heat transfer fluid of heat systems

Ženožička, Filip January 2018 (has links)
The subject of this diploma thesis is the design of heating and hot water in the administrative building in Zlin on Jižní Svahy. The building has five floors above ground and one underground floor. There are designed two variants of heat source for heating and hot water (transfer sta-tions and gas boiler). Part A solves water quality in heating systems. Part B deals with design of the heating system, hot water heating, insurance and facility expansion, technical report and drawings heating in the building. The last part C is the experimental measurement of the quality of heating water in the CZT systems.

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