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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.
131

Výskyt a interakce jodu v přírodním prostředí se zaměřením na hydrosféru. / The occurrence and interactions of iodine in a natural environment, focused on the hydrosphere.

ŠEDA, Martin January 2013 (has links)
Iodine is an important element essential for higher animals. A large part of the global human population suffers from a lack of iodine; elucidation of transfer and mobility of this element in the environment, water, soil, air and in organisms is thus very important. The aim of this work was the elaboration and optimisation of the method for determination of very low concentrations of iodine in the waters. The mass spectrometry with inductively coupled plasma (ICP-MS) technique was used. It has been shown that using of different filter types during sample preparation had no significant effect on the content of impurities in the filtered sample. Antimony was recommended as an internal standard, despite commonly used elements (indium or tellurium). Samples were not preserved because nitric acid caused volatilization of iodine from the sample and the addition of aqueous ammonia had no significant effect. The optimised method was tested on several groups of water samples, including precipitation, surface water and lysimetric waters. From autumn 2009 to summer 2010, a part of the Blanice River (Šumava Mountains, South Bohemia) was sampled. The average content of iodine in samples ranged from 1.48 ? 0.30 ?g?dm-3 (April 2010) to 3.05 ? 0.38 ?g?dm-3 (July 2010). The average content of iodine in samples from all tributaries of the Blanice River ranged between 2.52 ? 1.63 ?g?dm-3 (March 2010) and 3.67 ? 1.37 ?g?dm-3 (July 2010). The concentration of iodine in the monitored surface waters did not change significantly along the flow of the river. The other two streams were sampled near Rapotín village (Jeseníky Mountains, north Moravia). The average contents of iodine were as follow: Annov (upper stream) 1.60 ? 0.65 ?g?dm-3, Annov (lower stream) 1.88 ? 1.18 ?g?dm-3, Salaš (upper stream) 1.77 ? 0.92 ?g?dm-3, Salaš (lower stream) 1.42 ? 0.58 ?g?dm-3. Generally, the data showed that considering iodine, the area of Šumava had slightly higher levels than those observed in the Jeseníky Mountains. Precipitation collected in the South Bohemia (Arnoštov village and city of České Budějovice) and in Jeseníky (Rapotín) contained less iodine compared to surface waters, and rarely exceeded 3 micrograms per liter of water. The situation has changed in the spring of 2010, because of the occurrence of volcanic dust and ash over the Czech Republic. This volcanic cloud came from the sudden activity of the Eyjafjallajökull Volcano (Iceland). In the mentioned period, the contents of iodine in precipitation were increased several times at all sample collection sites. This is an indirect evidence that iodine could be released during volcanic eruptions and transferred over long distances through the atmosphere. It turned out that the wastewater treatment plant can eliminate iodine in wastewater only partially. However, the wastewater treatment plants in the monitored region were too small to evaluate the overall impact on the environment. The maximum iodine content at the outlet of the wastewater treatment plant Prachatice town (South Bohemia) was 28.5 ?g?dm-3, which is several times higher than natural levels in the Živný stream, to which the treated water flows. Lysimetric water samples were collected from lysimeters installed in three nearby plots in Arnoštov village (Šumava, South Bohemia). The highest concentrations of iodine were found on plot where cattle were grazed. These values were significantly higher (average 4.38 ? 1.74 ?g?dm-3) than those obtained from a site used as hay meadow (average 2.69 ? 1.19 ?g?dm-3) or an untreated meadow (average 2.25 ? 1.39 ?g?dm-3). Iodine therefore probably originated from the urine and feces of grazed cattle. This thesis contributes to the total knowledge of iodine, particularly to the part concerning determination of iodine in the hydrosphere.
132

Biodiverzita a ekologie makrofyt vybraných stojatých vod v aluviu horního toku Lužnice / Biodiversity and ecology of makrophytes in selected standing waters in the floodplain of the Lužnice river

DVOŘÁKOVÁ, Olga January 2008 (has links)
This is a field study describing seven backwaters in the floodplain of the Luznice river. The backwaters include alluvial pools, river arms and oxbows which differ in their genesis, morfology, hydrological régime, macrophyte vegetation and chemistry of water and sediments. This study was carried out in the Trebonsko - Protected Landscape Area and Biosphere Reserve, South Bohemia, Czech Republic. The data of species composition of the vegetation on transects of the backwaters are supplemented by water and sedimet analyses.
133

Kvalita pitné vody určené k hromadnému zásobování obyvatel / The Quality of Drinking Water in Public Distribution Systems

SOMPEKOVÁ, Zuzana January 2010 (has links)
This research project was aimed at monitoring the quality of drinking water that is supplied to the inhabitants of small villages. The quality of drinking water produced by small waterworks in South Bohemia, in municipalities Mazelov, Ortvínovice, Doubravka and Rábín, was studied. Sanitary analyses of drinking water samples carried out by the waterworks operators in 2004-2009 showed some variability in the concentrations of free chlorine, nitrates, pH, turbidity and the content of Escherichia coli in all the waterworks during the investigated period. The hypothesis assuming that the quality of drinking water produced by water treatment from small water sources is stable and that it does not vary in some key indicators, such as nitrates, the contents of Escherichia coli etc., throughout the year was not confirmed. The other hypothesis assuming that the number of small water sources used for public drinking water supplies decreases during the period was confirmed. The causes of these changes depend on many factors, such as the location and source of drinking water, the type of treatment plant, and, last but not least, the quality of service and economic potential of the waterworks operators play a negative role.
134

Analýza stížností odběratelů pitné vody / Drinking water customer complaints analysis

Trněná, Eva January 2019 (has links)
The diploma thesis deals with the analysis of complaints from drinking water customers, particullary about water quality. Within the theoretical part, it presents both the view of the customer of the drinking water and the view of the operator of the water supply system. It also presents possible ways to use drinking water customers complaints as indicators of water system service quality. Further, the thesis focuses on the satisfaction of customers and their trust in the operators of water supply systems. An analysis of complaints of drinking water users on the quality of water that has been received by the operator during the last five years has been performed as part of the case study in the practical part of the thesis. The cases are interpreted in context of the conditions at the given site of the water supply network.
135

Plán pro zvládání sucha a nedostatku vody / Plan for drought and water scarcity

Bakota, Filip January 2019 (has links)
The aim of the diploma thesis is to describe and prepare the pilot plan for drought and water scarcity for the selected locality, according to the prepared amendment of water law. Recent years have shown that drought will play a significant role in water supply in the future. Therefore, the need for tools to provide procedures and guidelines for individual administrations is more than important. The first part of the diploma thesis deals with issues of drought and water scarcity, climate change and prospects for the future. The next section describes a plan for drought and water scarcity. In the next parts of the diploma thesis, there are procedures that can mitigate or completely avoid the consequences of drought. From this informations, a pilot study of the plan for drought and water scarcity for the town of Počátky is being prepared in the next part.
136

Vodohospodářská analýza a boj se suchem v povodí řeky Rokytné / Water analysis and combating drought in the Rokytná river basin

Říha, Tomáš January 2020 (has links)
This diploma thesis focuses on water management analysis of the Rokytná River and finding suitable precautions usable by municipalities when dealing with drought and lack of water in their administrative district. The short research at the beginning of the thesis summarizes problematic of drought and lack of water in the Czech Republic, including the current state and overall context. Next part focuses on the assessment of current state of the Rokytná River basin, based on performed reconnaissance of the basin and processed analysis of a part of the basin delimited from km 0,0 to km 16,7 of the river, between towns of Ivančice and Moravský Krumlov. This analysis concentrates on finding factors, which can contribute to extent of drought impact in this area. It also contains a suspended load study of the waterway, which writes up granularity characteristics and calculation of the amount of transported material from a suspended load sample, taken from the bed of the Rokytná River. The overview of suitable proceedings and precautions follows, based on findings in previous parts of the diploma thesis. The conclusion of this thesis consists of very suggestion of suitable steps and precautions related to particular localities in the Rokytná River basin. Target is to enhance the retention ability of the region and to minimize the impact of both drought and floods. The result of these actions should be the empowerment of environmental sustainability in this particular area. Conclusions of this thesis can be used by municipalities and other administrative bodies when creating an approach of combating drought and when deciding about the implementation of relevant precautions.
137

Stochastické modelování spotřeby vody ve vodovodní síti / Stochastic modeling of water consumption in the water supply network

Kopecký, Josef January 2021 (has links)
This thesis deals with stochastic water demand modellling in the water supply network. In the opening section, a research is created, where two different approaches to stochastic modelling of water consumption are presented. The practical part describes the creation of a deterministic hydraulic model and its calibration. Generated stochastic water demand patterns with a small time step of 1 minute, are then inserted into this model. Each household is assigned with a unique water demand pattern. Then a hydraulic analysis was done. A comparison of deterministic and stochastic approaches is presented at the end of the thesis. The comparison shows, that small-time step modelling does not have a big impact on the pressure ratios in the water supply network, but has a huge impact on the maximum flows and speeds occurring in links of the hydraulic model.
138

Sledování koncentrací organických látek podél technologické linky úpravny vody ve Štítarech / Monitoring of concentration of organic matter along the technological line of drinking water treatment plant in Štítary

Hubená, Renáta January 2010 (has links)
General part of thesis deal with information on technology of water treatment and its changes at drinking water treatment plant Štítary. In experimental part of the document are presented treated data on monitoring of concentration of organic matter along the technological line of reconstructed drinking water treatment plant in Štítary for period since 2009 to 2010.
139

Posouzení základních ukazatelů odpadní vody firmy Dermacol / Assesment of basic characteristics of waste water from the Dermacol Company

Fribertová, Marcela January 2010 (has links)
This master thesis is focused on waste waters from cosmetics industry and basic indicators of these waters. The pollution of the environment caused by increase industrial development has a negative effect on ecosystem. Waste waters are part of the pollution. In theoretical part a basic indicators of waters (its definition and way of determination) have been described. Membrane processes for water purification have been mentioned as well – particularly the ultrafiltration. The experimental part of thesis deals with practical determination of indicators mentioned in methods described in the theoretical part. Results are discussed at the close. The discussion is focused on evaluation of efficiency of the device for waste waters adjustment, which is in use in the Dermacol company, which produces cosmetics products.
140

Využití potenciálu tvorby trihalomethanů k hodnocení účinnosti úpravy povrchové vody / Application of trihalomethane formation potential for evaluation of drinking water treatment efficiency

Halešová, Barbora January 2013 (has links)
The main theme of this thesis is the usage of the test investigating the formation potential of trihalogenmethanes (THM FP) and its comparison with conventional indicators of water quality (CODMn, A254 and colours). As for the experimental part of the thesis, rating of the effectiveness of selected technological procedures has been applied (e.g.: coagulation, adsorption and ozonation in the act of treatment of artificially prepared water model with a higher content of humic substances in laboratory conditions). Based on the obtained results, it was found that the common indicators of water quality have very similar attributes and also complete each other. On the contrary, those attributes of indicators may not be sufficient in case of the evaluation of water quality with high content of humic substances. The findings made illustrate that the THM FP test enables the accurate evaluation of water quality, especially in connection with the content of an organic material susceptible to chemical changes. THM formation potential has proved its high value and also has confirmed that it can appropriately complete the other standarts that are being used for assessing the quality of treated water up to nowadays.

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