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Updated summary of Tertiary relics in the vicinity of Pilsen
Trnka, Jan ; Sakala, Jakub (advisor) ; Pšenička, Josef (referee)
The aim of the bachelor thesis is to consolidate the knowledge from previous research on Tertiary relics in the vicinity of Pilsen, especially in the districts of Pilsen-City and Pilsen-North. Emphasis is placed mainly on sites that are important in terms of their extent or have provided identifiable samples of plant macrofossils or pollen in the past. In particular, these are the sites Dobříč/Jarov, Ejpovice/Kyšice and Horní Bříza - Modrý kříž. To a lesser extent, these are summaries of the manifestations of volcanism in the defined area. The thesis will be a possible starting point for a follow-up thesis, in which the student will process new findings of plant macrofossils from his own field research. Its further content will be a critical comparison of the individual reconstructions of the palaeochannel network and the determination of the approximate flow direction both for individual relics and the determination of the dominant drainage direction of the entire area.
Numerical Model of Water Flow in the Upper Reservoir Nové Mlýny
Winkler, Stanislav ; Zachoval, Zbyněk (referee) ; Marton, Daniel (advisor)
Diploma thesis is focused on understanding problematic of sedimentation in reservoirs with relation on flood episodes. For creating numerical model was necessary to ensure data about morphology of the river, granular composition of the riverbed and hydrology data. In thesis is written how were obtained these documentations, description of creating numerical model in program HEC – RAS 5.0.7. and results of done simulations of real flood episodes, which took place in years 2004, 2005, 2006, 2009, 2013. Output is evaluation each flood episode, description of grain class curves and evaluation of yearly flow before change of riverbed due to transport of sediments and after change of morphology of riverbed.
Monitoring of water and sediments contamination after uranium ore mining
Kurfürst, Vlastimil ; Komendová, Renata (referee) ; Čáslavský, Josef (advisor)
This paper deals with the monitoring of water contamination and sediments in the area of Olší - Drahonín. Firstly, the water contamination released into the river Hadůvka is evaluated. Secondly, the sediments in the river are monitored and the surface water flow is evaluated. Finally, the water treatment technology and sampling is described. A description of the separation methods and choice of standard methods is outlined.
Geochemical Study: Sediments as a Source and/or Trap of Mercury Contaminatin.
Májska, Milada ; Amouroux, David (referee) ; Zdeňka, Svobodová (referee) ; Dočekalová, Hana (advisor)
Rtuť je v přírodě přirozeně se vyskytujícím toxickým prvkem, jehož globální emise jsou ovlivňovány zejména antropogenními zdroji znečištění. Obrovský globální nárůst v usazování rtuti, zejména ve vodných ekosystémech, byl zaznamenán současně s počátkem průmyslové revoluce. Sedimenty jsou posledním místem úložiště nejrůznějších komplexů rtuti. Rtuť však zde může být přeměněna na toxičtější organickou formu, methylrtuť, pomocí transformačních procesů kontrolovaných různými fyzikálními, chemickými, ale i biologickými faktory. Navíc mohou být specie rtuti remobilizovány ze sedimentů pomocí difuze a resuspenzace a tak se sedimenty mohou stát i potenciálním zdrojem rtuti. Proces bioakumulace a bioobohacování tak pokračuje v potravním řetězci, ve kterém se člověk, i další zvířata, stává konzumentem methylrtuti. Stanovení celkové koncentrace rtuti není dostačující k porozumění osudu rtuti v přírodním prostředí a tak stanovení MeHg poskytuje nezbytnou doplňující informaci. Dostatečně citlivá a přesná analytická metoda pro stanovení specií rtuti je nezbytným nástrojem environmentální chemie. Metody vhodné pro stanovení specií rtuti v sedimentech jsou popsány v části metodologie disertační práce. Metoda stanovení methylrtuti v sedimentech pomocí automatické Headspace vybavené pastí („trap“) a spojené s plynovou chromatografií a fluorescenční detekcí je zde také popsána. Zvláštní pozornost je také věnována potřebám zásad čistého vzorkování, skladování vzorků a přípravě vzorků před samotou analýzou, jakož i samostatné části věnující se terénní studii rtuti a methylrtuti v sedimentech vytipovaných lokalit. Sedimenty jižní Moravy a severní Francie jsou srovnány z hlediska znečištění rtutí. Specie rtuti a další ukazatele (Fe, Mn, S) byly analyzovány v sedimentech, pórové vodě a povrchové vodě řek Dele a Lys (Francie) a Jihlava a Morava (Česká republika). Z hlediska posouzení vodních ekosystémů a jejich znečištění rtutí, je vhodné znát koncentraci rtuti v pórové vodě a posoudit dostupnost rtuti ze sedimentů. Technika difuzního gradientu v tenkém filmu je vhodným způsobem jak stanovit koncentraci rtuti v pórové vodě sedimentů. Do roku 2005 bylo použití této techniky pro měření rtuti značně limitováno. Ale nedávný pokrok především v dostupnosti možných sorpčních gelů vhodných pro stanovení rtuti umožnilo využití této techniky i pro stanovení rtuti. Byly použity různé sorpční gely: Spheron.Thiol, Duolite GT-73 a TiO2. Řeka Dele představuje past enormního množství antropogenní rtuti pocházející z průmyslových zdrojů a je považována za potenciální významný zdroj methylrtuti pro okolní prostředí a živé organismy především. Poslední část dizertační práce se zabývá aplikací dobře zavedeného experimentu využívajícím stabilní isotopy ke studiu metylačních a demethylačních procesů v sedimentech řeky Dele. Obohacené stabilní značkovače rtuti v anorganické formě (199Hg) and methylované formě (201MeHg) byly přidány do sedimentů. Tyto označené specie rtuti tak pomohly sledovat osud specií rtuti a vypočítat rozsah jejich přeměny v průběhu experimentu.
The issue of determination of tin in environmental matrices
Bušinová, Markéta ; Sommer, Lumír (referee) ; Doležalová Weissmannová, Helena (advisor)
This diploma thesis deals with the retrieval of the content of tin in environmental media, the circulation in them and possibilities of the determination of tin in the environment. Summarizes available information on the properties of tin and its compounds, the occurrence and circulation of tin in environmental and determination of tin in environmental media, attention is paid to the determination of total tin content using method of ET-AAS. The experimental part is focused on optimization methods of determination for the ET AAS and selection of a suitable extraction procedure for determination of total tin content in soils and sediments. The best procedure for the determination of tin in the ET-AAS was applied to samples of soil, sediment and water. As the optimum matrix modifier was chosen the solution of Pd (NO3)2 in 5% ascorbic acid, the optimum pyrolysis temperature was 1400 °C and atomization temperature 2400 ° C. Neither of extraction procedures examined were found to be an appropriate procedure for the determination of tin in environmental samples and further work is necessary to optimize the method of separation.
Sewage sludge and sediments evaluation via ecotoxicity tests
Ondrová, Jana ; Vávrová, Milada (referee) ; Zlámalová Gargošová, Helena (advisor)
Sediments and sewage sludges are part of the environment. Sewage sludges are formed in wastewater treatment plants as solid residues after water purification, therefore they have antropogenic origine. Although the sediment are formed by natural processes, humans also contribute to their formation. Sediments and sewage sludges can be a reservoir of a number of contaminants, due to their properties. Utilisation of sediments and sewage sludges as material for recultivation or a natural fertilizer is currently supported. But after application to the land, contaminants can be released to the environment. The consideration of ecotoxicological effects of sediments and sewage sludges is very important. Sediments and sewage sludges were ecotoxicologicaly evaluated by bioassays with water leacheate and by whole sediment bioassays. Daphnia magna, Thamnocephalus platyurus, Sinapis alba and Lemna minor were used to perform tests with water leacheate. Heterocypris incongruens, Lactuca sativa and Eisenia fetida were used to perform whole sediment tests.
Tin and his species in the environment
Bušinová, Markéta ; Moos, Martin (referee) ; Doležalová Weissmannová, Helena (advisor)
Presented bachelor thesis is background research on tin and his species in the environment. Mainly deals with the effects of inorganic and organic compounds of tin on elements of environment. The work resumes accessible information about properties of tin and his compounds, entry of tin and his compounds into the elements of environment, cycle and occurrence of tin speciation in water, soils, sediments and biological materials.
Tin and its compounds in the environment
Ježek, Stanislav ; Kosárová, Hedvika (referee) ; Komendová, Renata (advisor)
The aim of this thesis is the actual elaboration literature search concerning the issue tin in the environment. It includes chemical and physical properties, occurrence and tin cycle in the environment. It also contains possible methods for extraction and determination of tin and its compounds.
Ecotoxicological evaluation of sediments
Dobešová, Zuzana ; Doležalová Weissmannová, Helena (referee) ; Zlámalová Gargošová, Helena (advisor)
Sediments of lotic and lentic water can be a reservoir of a number of contaminants, which can enter the aquatic ecosystem either due to the controlled discharge of waste water or leakage of various accidents or technological devices. Sediments can hereby affect not only the aquatic ecosystem, but also the terrestrial system in the case that they will be used as fertilizer or as a material for the recultivation. For this reason it is important to consider their potential ecotoxicity. Sediments were subjected to ecotoxicological bioassays and their potential ecotoxicity was assessed. The phytotoxicity assays on terrestrial plants Sinapis alba, Lactuca sativa and Allium cepa were used and the effects of aqueous extracts of sediments on the inhibition of growth their root were evaluated and the value of IC50 was determined. For the ecotoxicological assessment of sediments and determination of IC50 value also Lemna minor as a representative of aquatic plants was selected. For more objective assessment of the sediment ecotoxicity aquatic invertebrates as Artemia salina and Daphnia magna were selected and the value of LC50 or EC50 was determined.
Relation Between River Flows and Suspended Sediments in the Selected Hydrometric Profile of the Thaya River Basin
Bobková, Dominika ; Menšík, Pavel (referee) ; Marton, Daniel (advisor)
The issue of the sediments of their transport and subsequent storage in water basins is an important topic which is perceived very seriously by the water management expert public. Therefore, work in this area is very desirable. The aim of bachelor‘s work is to find and estimate possible dependencies between average daily discharge and average daily values of non dissolved substances carried in suspension. The dependencies will serve as a partial basis for addressing the ATCZ28 SEDECO Sediments project, ecosystem services and interrelation with floods and droughts in the AT-CZ Border region. The data are analysed in different periods of time. The result of the analysis is the trend line regulations and the degree of dependence between flows and concentrations, which is expressed by means of a coefficient of determination. The practical application is performed on data measured in the Trávní Dvůr profile on the Dyje river for the years 1996 and 1997.

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